The worldwide practice of urban agriculture has shown itself to be an often-successful model for the inclusion of different urban sub-communities into an intentional social organisation typically focused on producing the necessary resource of food. But the general value of urban agriculture as a means of achieving several other community objectives – in building community capital – is of equal significance. This chapter suggests how community capital is composed of seven dimensions, each of which is commonly addressed in some way through the practice of urban agriculture. The multi-faceted character of successful community-based urban agriculture examples is based upon the addressing of one or more of these seven dimensions to create a place-based form of grassroots community development, while also involving representatives of often-marginalised subgroups, such as women, youth and the poor.

Urban Agriculture and the Building of Communities

Introduction

Examples of urban agriculture worldwide, including many described in this book, display situations where the practice of city farming accommodates often marginalised subgroups. Urban farming repeatedly allows for the inclusion of women, children, the poor, the homeless and the elderly into constructive food production activities (see chapter 5). Thus urban agriculture, in a manner consistent with the practice of conventional community (social and economic) development, can be a constructive contributor to city neighbourhoods, and the social networks of entire cities (see also the discussion in chapter 1 on social impacts). This goal is articulated in the mission statement of the American Community Gardening Association, a key non-government supporter of city farming in the US and Canada:

Kenya Green Towns extension agent Elijah Githee instructs members of the Together Home Craft Self Help Group on planting lettuce in plastic containers, Nakuru, Kenya.

The Association recognises that community gardening improves the quality of life for people by providing a catalyst for neighbourhood and community development, stimulating social interaction, encouraging self-reliance, beautifying neighbourhoods, producing nutritious food, reducing family food budgets, conserving resources and creating opportunities for recreation, exercise, therapy and education. (ACGA, 2006)

Evidence for the growing of food within the social structures of cities can be found throughout recorded history. As societies and cities have changed, so too has the role of urban farming and food production – particularly when much of the world's population, especially those in developed nations, participates in an efficient global system of food production and distribution. In richer countries, urban and peri-urban food production, whether through community gardens in the US or allotment gardens in Europe, is viewed primarily as a desirable addition to the global corporate food network. In developing nations urban agriculture maintains its importance as a source of meat, fruit and vegetables for those lacking the access and income to participate in the global food economy.

Whether practiced in rich or poor nations, certain forms of urban agriculture display a social organisation that focuses on creating stronger urban communities. These activities reflect a grassroots understanding of local needs and skills, and link this to a complimentary understanding of the multiple functions of urban agriculture in a way that, when successful, grants participants a sense of shared accomplishment in how the methods and results of food production and distribution translate into something more encompassing. We call such activities community-based urban agriculture (CBUA), and they are the subjects of this chapter.

The thesis of the chapter is that urban agriculture, as a community-driven and community-managed activity, makes significant direct and indirect contributions to urban residents and urban regions. These contributions are similar to the targeted goals of place-based community development as set by national, sub-national and local governments, foundations, and international and local aid agencies. But instead of seeing the members of an urban community as the object of technical development planning, CBUA is a vehicle for a more grassroots form of community development; one that grants its practitioners a sense of inclusion, dignity and accomplishment that might not occur through standard community development practice.

A "community" practicing urban agriculture is often – though not necessarily – a community of place, whose participants share a common home location and create a framework for involvement and inclusion connected to the sharing of this space over time. These actions improve the lives of those in the community both individually and collectively. The concepts underlying CBUA across the world are similar to those of "civic agriculture" in the US, and centre within urban contexts and locations the characteristics of civic agriculture that "reference the emergence and growth of community-based agriculture and food production activities that not only meet consumer demands for fresh, safe and locally produced foods but create jobs, encourage entrepreneurship, and strengthen community identity." (Lyson, 2004).

School children learn about growing vegetables and healthy food in Lima, Peru.

Although their differences are not always distinct (and indeed community building requires entrepreneurship), we can distinguish CBUA from other proactive forms of urban agriculture (that also of course may have an important social impact), in particular from: (1) subsistence farming by individuals for themselves and their families; (2) entrepreneurial, market-oriented urban agriculture, often consisting of privately-owned, profit-making businesses; and (3) leisure or recreational gardening (see also chapters 1, 4 and 7 for a discussion on different types of urban agriculture). CBUA, in contrast, is a shared activity focused on intentionally building communities, while producing fresh food, fuel, medicine, ornamentals and handicrafts for local consumption and distribution. At its core – whether through community gardens or allotments, school gardens, cooperative farming on commonly-owned sites, etc. – CBUA provides social interaction, a key attribute of any thriving community. And as food is a basic need of all community members, CBUA provides a centrepiece for shared stakeholder interaction around a necessary activity. This interaction involves mobilisation of the community to establish the objectives and form of the urban agriculture activity, the acquisition of needed resources, the understanding of relevant regulations, and the organisation of the project's execution.

It is important to understand that CBUA is not scale-dependent; in theory, the affected community could be an entire city or a single neighbourhood. In practice, however, CBUA works well when it builds upon the initiator's cognitive understanding of a particular community, whether a prison or a housing estate, to which the project can be tailored and the benefits appropriately directed. And at the larger scale of the city, the aggregation of many CBUA activities can have a significant effect on the total quantity of locally-produced food available, the reuse of municipal waste, and lower living expenditures among the poor.

Cities are complex social, economic and political entities. Thus the ownership and administration of CBUA activities can also be complex when compared to rural agriculture. Examples of this complexity would include self-organised community gardens and gardens supporting community kitchens; food cooperatives and community supported agriculture sites (CSAs); leases based on payment of a share of the crop or of its value; leases to not-for-profit organisations (NGOs and CBOs) with subcontracts to the farmer; company gardens for employees; and perhaps most typical, land use arrangements with outside parties owning the land or controlling it in some other way. Although, in general, CBUA has a permanent social and economic role in modern cities, individual operations are often only temporary occupants of urban sites.

According to surveys by WHO, FAO and UNICEF, the cost of food to low-income communities in most countries demands one-third to two-thirds of family income. Since food production through urban agriculture takes place within the community, food acquisition need not go through the money or formal economy, and thus can direct scarce individual or family resources toward other needs. The social ties among community members establish efficiencies in the informal economy between CBUA production and distribution through, for example barter. By combining the economic and food security benefits of CBUA, participating individuals and families are able to purchase better health care, housing and education, common goals of community development. These individuals can also improve their standard of living by becoming greater consumers of products from rural areas and the global marketplace. When such improvements in living standards through urban agriculture occur within certain sub-populations, such as the poor and homeless, it supports the argument made by CBUA advocates that outside support for urban agriculture can and should come from the traditional supporters of these sub-populations.

As important as food production and distribution are to the concept of CBUA, the fact that it occurs in a specific location, or place, having a physical identity and established social connections, is equally important. The term "place" consolidates in a single location a social component; a built environment of housing, institutions, infrastructure and other land uses; a natural environment of air, water, earth and vegetation; a localised economy; and some form of governmental or institutional structure. It is in terms of "place" that CBUA most is strongly integrated with community development:

[Urban development] find[s] realization in a place, in a specific spatial context in which... social processes and institutions intersect with the lives of the city's most vulnerable citizens. And it is in a place that over time... social burdens accumulate. We need to understand those places and make them better for, more than anything else; city-making is place-making (Bender, 2000).

Community Capital: How urban agriculture builds place-based Community

A significant percentage of the 80,000 residents of Nakuru town, located in Kenya's Rift Valley 150 km northwest of Nairobi, have been affected by the HIV/AIDS plague devastating the countries of sub-Saharan Africa. Poverty is evident in the many slum areas of Nakuru and the resources to acquire HIV/AIDS antiretroviral medicines are scarce. Nevertheless, in early 2005, as many as 80 community groups, many organised by women directly affected by HIV/AIDS in some way, have established or are creating, with the help of outside agencies, small bio intensive vegetable gardens to improve their diets and those of their families. These community groups, with names such as the Together Home Craft Self Help Group and the Baraka Kiamunyi Women's Group, are growing food organically on sites as large as 0.6 ha outside Nakuru and as small as 50 m2 in backyards behind slum homes in town. In these gardens, one finds maize, bananas, passion fruit, beans and other vegetables, grown through the use of compost and manure. Many of these projects are given technical assistance by the Kenya Green Towns Partnership Association together with Urban Harvest in Nairobi. To these poor urban farmers, the nutritional value of the food produced is often as important as the income generated by selling their food to others in town (in the case of the Together Home Craft Group this is combined with the selling of textiles they make and market.)

Even when the school has no proper land, children can learn how to grow crops

Similarly, in cities across North America urban NGOs have dedicated many of their projects towards helping poor and at-risk city children and teenagers discover how the life lessons of food production and distribution can help them overcome the negative influences of their home environments. In the Roxbury and Dorchester sections of central Boston, The Food Project enables young people to attain the skills and confidence to become agents of change in their often-troubled neighbourhoods. Each summer for over ten years, 140 young people – both from inner-city Boston and from its affluent suburbs – come together to grow food on urban and suburban sites, donate or sell the food throughout the Boston area, and, most importantly, share their knowledge and pride in their accomplishment with others across the US. The Food Project is at the forefront of developing a new community development model that combines food security actions with youth leadership training using a genuinely modern, even hiphop, approach.

These examples from Kenya and the US epitomise the way that urban agriculture serves as an intentional vehicle for a special form of place-based community development. The term intentional signifies awareness on the part of the initiating group that urban agriculture represents both an end in itself (through the harvesting of nourishing food) and a means by which to strategically achieve additional social and community ends. The women's groups of Nakuru, for example, are largely composed of members of the neighbourhoods where the gardens are located, and view urban agriculture as a means of exercising their sense of self-determination and dignity in the face of hardship. The groups are self-organised, and individually solicit the outside assistance they know they lack to fully achieve their goals. Most importantly, their collective action strengthens their identity as part of a social assemblage, an interacting population in a common location.

This building of community can also be expressed as increasing community capital. Seven dimensions comprising community capital have been identified, and their interaction through the production of food and other agricultural products of CBUA will be discussed. Chapter 10 of this book follows a similar and complementary approach by identifying five dimensions of household-based assets found in the literature on rural livelihood strategies (such as Farrington et al., 1999) that are also applicable to poor urban households striving to earn a living. The seven dimensions of community capital introduced in this chapter are adapted from community development and sustainability studies in the US (such as Flora et al., 1999), and aim to more precisely define the particular social outcomes of CBUA.

These dimensions of community capital found within CBUA activities are:

• Human Capital: the health, education, skills of the individuals involved
   
• Social Capital: the strength of groups, networks, the common vision among their members, and the creation of bridging networks across different groups
   
• Political Capital: the dynamics of group organisation and leadership, and relations with government and supporting agencies
   
• Cultural Capital: the values and heritage of the community, and the celebration of such
   
• Economic Capital: the investments, savings, contracts and grants
   
• Built Capital: the physical settings – land, housing, other buildings, infrastructure
   
• Natural Capital: the local air, land, water, biodiversity, scenery

This deconstruction is useful for the analysis of social communities needed for programme and project planning and evaluation, partner identification, leadership training, networking, the acquisition of funding, and political support. It is essential to identify each of these dimensions and bring them into focus for the community and for outsiders in order to conceive, design, and implement community building projects, such as CBUA. Defining the outcomes and results of community development programmes requires establishing indicators for each of these seven dimensions through, for example, surveys and goal identification. The practice of CBUA can and does contribute to all seven essential dimensions of community capital. The following is a brief overview of how each is displayed in CBUA. (Note that several of these dimensions are discussed in greater detail in other chapters of this book.)

Human Capital

The building of human capital within each individual begins with good health that, in turn is built upon good nutrition. At its highest level of community benefit, CBUA reduces a community's level of food insecurity, seen in the lack of access by individuals and families to nutritious food, whether by availability or cost, over the course of a week or month. CBUA makes nutritious food directly available, often through the informal economy, and is a significant source of nutrition and health (Bellows et al., 2004; Patel, 1996). Locally grown and raised vegetables, fruit, herbs, fish, poultry, livestock and dairy products can have one-third to two-thirds more essential micronutrients, minerals and beneficial fats than the same foods that have been stored, packaged, processed for more than a day or two. Better nutrition contributes to community development through improved brain development in the young, more vigorous work days for adults, and, in general, a stronger, healthier population. From a nutrition perspective, one of the most compelling justifications instituting CBUA is to provide sources of fresh vegetables to HIV/AIDS patients receiving antiretroviral drugs through community health providers, especially in situations when poor diets compromise the effectiveness of the medications.

A community-based food system is a secure source of good nutrition, but also strengthens other forms of human capital. For example, many studies examining conditions over the entire 20^th century identified school gardens as an excellent educational laboratory – not only for the practical knowledge of how food is cultivated and harvested, and for an awareness of composting and recycling, but for also introducing discipline, organisation and responsibility. As for adults, city farming grants an individual certain practical skills in production, processing and marketing unavailable in other urban industries.

Social Capital

Social capital can be built in place-based communities that often lack social cohesion and shared participation around a common vision. Urban farming within or at the edge of a location brings the members of that location together, most frequently outdoors, and generates interaction. As mentioned earlier, a distinguishing characteristic of successful CBUA is that it generates groups to organise and manage a project(s). Additionally, CBUA often forms bonding and bridging networks that did not exist prior to its initiation. In the US, Aspen Farms, a community garden in primarily African-American West Philadelphia, represents many similar projects in the manner by which its democratically-based organisational structure evolved over time.

Aspen Farms looks like a miniature farm, but it is more like a town, with individual plots and common ground... There are meeting places and shared resources, like the greenhouse, the compost pile, the water supply and irrigation system. Originally colonised in 1976... the garden has continued to change, with individual initiatives, negotiations, and group decisions. The gardeners set the rules and elect officers, including a chaplain. (Spirn, 1998)

Social capital is also built by the contributions CBUA makes to community food security. A sense of community ownership over its local food system leads to a collective sense of empowerment, with those involved thinking better of themselves and their neighbours and being proud of their shared accomplishment. Similarly, an important sub-dimension in the building of social capital through CBUA is the opportunity for women to collectively initiate, structure and implement successful projects tailored to the identified food security needs of their home communities, despite local constraints on resources or control attributable to gender-based discrimination (see Chapter 5).

Political Capital

Building community through CBUA in most cases requires political action, and identifying and measuring political capital is constructive in guiding these programmes. One measure is programme organisation, and how decisions are made – democratically, autocratically, or some combination of the two. Another measure of political capital is the relationships with those having municipal power in the town or higher government levels. Typically, it is empowering to create active connections to political parties and advocacy groups.

Leadership, and the voice that accompanies leadership, is perhaps more essential to the dimension of political capital than to the other dimensions of community capital. Identifying and promoting leadership within a CBUA activity is thus an essential element in developing its associated community; this is a characteristic objective of youth-centred NGOs involved in urban food production, such as Added-Value in the Red Hook neighbourhood of Brooklyn, New York City, which (in a similar manner to The Food Project in Boston) simultaneously addresses both community food insecurity and the need to provide Red Hook youth, and particularly young women, with avenues to develop their leadership capacities. And in democracies where citizens have some influence over public policy, the concept of municipal and regional food policy councils can structure and facilitate the creation of supportive policies by those empowered through their CBUA experiences (Borron, 2003).

Members of the Woodlands Farm Trust at work in London

Cultural Capital

Cuisine is an important element in building cultural capital through CBUA. Too often the cuisine of urban neighbourhoods is determined by outside food retailers with little thought to any distinct cultural traditions. Alternatively, a community-based food system empowers its members to express and enjoy their cultural cuisine as part of a larger set of cultural traditions. Rural farming is a valued element in the heritage of many cultural groups, and reactivating it in the cities of urbanising countries through the cultivation and processing of traditional crops creates significant ties to past traditions. Celebrations around food production, such as harvest festivals, are common, and are particularly important in connecting youth to their community's traditions.

The future of CBUA in North America is strongly tied to the growth of urban immigrant communities, and in how city farming is employed as a vehicle for assimilation and productive activity. From Afro-Caribbeans in Toronto (Werkele 2001) to Latinos in Los Angeles (Green 2004) immigrants lacking individual access to land are growing ethnic herbs and vegetables, both on highly visible sites and on sites more hidden from view. (As of this writing in March 2006, the 5.7-hectare South Central Farm in Los Angeles, and the organised community of 350 primarily Latino families who have farmed it for 13 years, are threatened with eviction by local authorities. Their mobilisation to save the farm has generated a nation-wide show of support for a notable example of sustainable urban farming, a cultural centre in multi-ethnic Los Angeles, and a symbol of the grassroots renewal of a section of the city devastated by the riots of 1992, the year the farm began.)

Economic Capital

Economic CapitalEconomic Capital The economic capital of a community is largely built upon the development of human, social, cultural and political capital, in that a healthier, socially and politically stronger community is better positioned to increase its wealth. City farming is a prime poverty-reducing industry. It empowers workers to greater productivity and can represent an expansion of a city's formal and informal economy. (Urban agriculture, whether producing food, fuel or ornamentals, is often the largest industry in the informal local economy.) To a greater extent than rural agriculture, the income generated by urban agriculture turns over within the community and city. It is a stable form of industry, in that the demand for food never fades and the urban producer is closest to and best attuned to market demand. Urban agriculture provides a part-time but stable income source for low and middle-income households engaged in non-secure employment. Savings are increased, particularly for those families that have direct access to local production without having to go through the formal economy.

While urban agriculture can offer certain economic benefits to individual actors operating independently from their communities, successful CBUA activities can channel the economic benefits that accrue to individuals into the larger community. One straightforward example is the successful cooperative vegetable and horticulture operations described in Chapter 7.

SCAGA men now run their own gardens separately (Cape Town, South Africa)

By investigating and implementing various entrepreneurial options CBUA can be an economic activity that facilitates the creation of communally-run economic activities such as farmers' markets, eating places, manufacture of handicrafts, retailing, and export commodities (Feenstra et al. 1999, Kaufman and Bailkey 2000). This is particularly true for activities involving women and the elderly, where established skills can be used, and those involving youth, through which new skills can be taught. Outside contractual relationships for inputs and products are increased through the introduction and expansion of new community businesses. The financing of community endeavours takes on a new dimension - grants and loans can increase in response to evident signs of a self-determined community implementing a sustainable urban development model (see Chapter 4).

Built Capital

The built capital associated with the physical qualities of CBUA is an important, often overlooked, form of community capital that is worth measuring and promoting. Taken in aggregate, the variety of urban agriculture in any one locale – whether in-ground cultivation, balcony gardens outside homes or greenhouses, or a small woodlot providing a village with fuel wood – creates a visible physical infrastructure similar to those of industry, retail, etc. CBUA makes productive use of available, often underutilised urban, suburban and periurban land for community benefit. In doing so, it represents an investment of shared effort on the land that has intrinsic aesthetic value (like the urban greening activities described in Chapter 14). Fruit-bearing street trees, a schoolyard with a thriving garden, and a busy street-side market clearly identified as a community endeavour are positive images to outsiders and a source of pride to community members. And at a different, more individualised scale, a home with a green roof, a dooryard garden and orchids growing in the kitchen has increased value. From a community development perspective, the principle of low-cost income-generating housing can be significant insofar as the value of each unit of the house is worth more than its shelter value.

Natural Capital

For 10,000 years, individual communities managed natural resources and biodiversity through mechanisms such as the commons, the sacred grove, the city forest, the annual assignment of user rights by community elders, and the public right of access to large bodies of water. Today, with large-scale environmental management primarily in the hands of governments and corporations, CBUA managers strive to incorporate modern principles of sustainable project management, such as composting and the reuse of solid wastes and wastewater, at a smaller scale. At one level, this represents simple practicality. Urban farmers are not inherently more environmentally conscious than rural farmers – they utilise urban waste because they farm the 2.5 percent of the earth where waste is most concentrated. But natural capital is further built in communities through the employment of newer techniques such as Permaculture and Agroforestry. Their employment in CBUA requires educating the community as to their rationale and methods, and their role as alternatives to other methods of food production. This strengthens communities in several ways, including building the self-confidence that encourages individuals to reach out and share this knowledge with others.

As with other dimensions of community capital, the building of natural capital lends itself appropriately to different forms of youth involvement. Growing Power, a community-based NGO currently operating in Milwaukee, Wisconsin and Chicago, has built its youth training programmes around its philosophy of advancing urban agriculture through small-scale, environmentally sustainable practices. Children participating in Growing Power's Youth Corps programme enjoy learning about and assisting with the low-tech, hands-on vermiculture and aquaculture projects that utilise donated outside waste products to produce vegetables, fish, and fertiliser made from worm castings.

The Establishment of Community-based Urban Agriculture Following Natural and Human Disasters

In this chapter, community-based urban agriculture has been presented as the result of a deliberate process of organisation that takes time to mature. Yet CBUA can be important in situations where time is of greater essence. For example, many, if not most, locations devastated by natural and human disasters have a need for the community-building practices of urban agriculture. Urban agriculture in post-disaster situations can provide several direct benefits to recovering areas: nutritious food, a mini-economy centred on food, useful new technologies, the conservation of local culture and the empowerment of women and youth. The experience of farming cooperatively during a crisis thus supports the community as it resettles in its home place. There is a basic procedural model. Just after a disaster, during their time in camps, refugees learn different urban agricultural techniques through technical training offered by NGOs, often humanitarian organisations. These techniques are then brought back to their home places upon leaving the refugee camps.

Farmer's markets bring rural and urban products to the urban consumers

Recent major natural disasters have created new CBUA opportunities. In summer 2005, hurricanes Katrina and Rita ravaged an area along the US Gulf of Mexico coast equal in size to many small countries. Because the storms occurred near the end of the growing season, traditional agriculture in a three-state region was severely damaged. To mitigate the loss, urban agriculture is being introduced on an interim basis. Raised-bed bio-intensive horticulture is being established in temporary mobile home parks, and small greenhouses are to employ innovative production methods. Internally displaced families are thus able to grow key elements of their traditional cuisine and supplement relief supplies with high vitamin and other micronutrient foods. A centuries-old way of life along the Gulf Coast will be at least partially restored.

On the other side of the world, the Sri Lanka Department of Agriculture has initiated a community agriculture programme to address the environmental, economic and, especially, the psychological damages resulting from the December 2004 tsunami. Authorities are offering to partner with residents (primarily in the western coastal districts of Kalutara, Colombo and Gampaha) to help develop projects ranging from the creation of "Family Business Gardens" within reconstructed housing, to small- and medium-scale agroentrepreneurship, to the improved value-added processing of fish harvests. The psychological recovery of tsunami-affected communities thus is built upon the relief supplied by the sum total of individual urban food production activities.

Kenya Green Towns extension agent Elijah Githee instructs members of the Together Home Craft Self Help Group on inground seed planting techniques, Nakuru, Kenya.

The methods of CBUA are also of value to communities formed by human disasters such as armed conflict. The siege of Sarajevo in the mid-1990s, for example, forced residents to engage in urban agriculture to replace food supplies that once came from outside the city. A more recent example is Somalia, a nation that has been in a state of war for over a decade. Refugees have emigrated north to Ethiopia, south to Kenya and west to Sudan. In all three places humanitarian organisations have assisted the refugees to establish agriculture within their campsites. Displaced persons within Somalia, fleeing from fighting in the north to the more stable centre and later from the disintegrating centre to the south, have also received assistance in establishing more intensive methods of agroforestry, small livestock and vegetable production than had traditionally been practiced in their rural villages.

The most extended projects have been along the border between southwest Somalia and northeast Kenya. Agriculture in Relief and Transition, a small group based in Washington DC, is a central agent behind the incorporation of food production into these camps. In this process refugees learn new skills in production, processing and marketing. Women are the predominant producers of vegetables and raisers of poultry, and also prepare food for local market sale (see for instance at www.theirc.org).

A positive outcome from this human disaster is that refugee women and men will eventually take home a new and more varied agricultural technology than that practiced before their displacement. At the conclusion of the crises several humanitarian organisations will move with the refugees to their former settlements and assist with the restoration of the local economy through the incorporation of these new skills.

Conclusion

The energy and motivation among city residents, particularly the poor, to allow urban agriculture to form a critical component of their shared wellbeing has been a constant in the history of community-based urban agriculture. The argument of this chapter is that the effective practice of CBUA, in both developing and developed nations, displays patterns similar to the best practices of local, place-based community development: self-determination, goal identification, the ability to access the necessary technical, financial and knowledge resources from outside the community, and the inclusion of marginalised segments of the community. Similarly, effective CBUA practice is accomplished by recognising from the beginning those dimensions of community capital – human, social, political, cultural, financial, built and natural – to be directly or indirectly enhanced through the creation and execution of the individual project. In essence, CBUA integrates and combines the actions and objectives of most, if not all, of the chapter themes contained in this book – community economics, gender, recycling and waste management, and the individual activity areas of urban agriculture (horticulture and forestry, livestock and aquaculture) – in a holistic manner.

Since 2000, CBUA has greatly benefited from the increased capacity of NGOs to support grassroots projects. In Cape Town, South Africa, Abalimi Bezekhaya (see the case study) represents a strong organisation focused at the local level. In North America, Heifer International has transferred the expertise gained at addressing hunger worldwide to projects in Canada and its home country of the US, particularly in Toronto, Chicago and New York. Heifer's North American projects have been particularly beneficial in immigrant communities, helping new Americans assimilate into new cities, while at the same time using farming to maintain important traditions of their home cultures.

Also in the new century, modern technology – the internet and mobile phones – is spreading new knowledge of organic and alternative farming practices developed by universities, extension services and other NGOs into more remote communities to improve urban agriculture production while also building the dimensions of community capital. In addition to longstanding problems of poverty and poor nutrition, community-based urban agriculture is being applied to more contemporary problems involving specialised sub-groups of larger communities. For example, in Kenya, Ethiopia, Zimbabwe, South Africa and other African nations, urban agriculture, in association with community-scaled health services, is seen as an important tool in the fight against HIV/AIDS (Small, personal communication).

While one is encouraged by the continued, and increasing, evidence of CBUA worldwide, one can also legitimately ask if the sum total of CBUA activities since the end of the last decade represents a true movement, or merely the simple aggregation of many disconnected examples. Many CBUA examples, such as Troy Gardens in the US, operate without the benefit of direct national and regional programmes that incorporate urban agriculture into community development planning. Commonly, national and municipal leaders and planners witnessing CBUA may simply see small initiatives on underused land, and not see the ways that these practices facilitate the same goals as their existing policy objectives. Advanced governmental policies supporting CBUA should begin with efforts to adapt the regulatory power of a jurisdiction to city farming practice. Recent guidelines to permit and regulate urban agriculture in Kampala, Uganda are based upon the recognition of its value to city residents. The guidelines go on to address the possible harmful effects of urban farming on the environment and public health (KUFSALC and Urban Harvest 2005). Such guidelines for Kampala reflect the well-known role of government as regulator in the public interest.

A more advanced form of government policy towards CBUA would go beyond regulation by identifying policy objectives within the separate dimensions of community capital as described earlier. For example, micro-enterprise loans can be provided to local community groups organising food distribution/marketing or some form of value-added processing and sale. In this role, government is not a barrier to CBUA as when it acts as regulator, but is instead a facilitator, supplying resources to self-directed groups that have displayed a requisite level of commitment and organisation to build their communities economically, and on their own terms.

With increasing urbanisation worldwide, community-scaled urban farming is assuming greater significance. Yet the opportunities for urban agriculture to strengthen both local food security and the economic and environmental health of cities are limited by the lack of widespread awareness of the multiple benefits of CBUA and by the general lack of relevant policies that recognise how CBUA is, in essence, an application of accepted place-based community development objectives centred around food production and community food security. Urban agriculture advocates would do well to remember this when urging increased support for their objectives.

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Premat, Adriana. 2005. Chapter 6: Moving Between the Plan and the Ground: Shifting Perspectives on Urban Agriculture in Havana, Cuba. In Luc J.A. Mougeot, ed. Agropolis: The Social, Political, and Environmental Dimensions of Urban Agriculture. Earthscan/IDRC.

Robyn Van En Center. 2006. Database on CSA farms in the US. http://www.wilson.edu/wilson/asp/content.asp?id=804  (accessed 8 March, 2006).

Small, Rob. 2006. personal communication.

Sneed, Cathrine. 2000. Seeds of Change. Yes! Magazine (Fall 2000).

Spirn, Anne Whiston. 1998. The Meaning of Landscape. New Haven: Yale University Press.

Warner, Sam Bass, Jr. 1987. To Dwell Is To Garden: A History of Boston's Community Gardens. Boston: Northeastern University Press.

Wekerle, Gerda R. 2001. Planning for Urban Agriculture in Suburban Development in Canada. Urban Agriculture Magazine No. 4.

Websites of Mentioned Activities and Organisations

The Siyazama Community Allotment Garden Association, Cape Town, South Africa


Abalimi Bezekhaya (Planters of the Home) is the leading urban agriculture organisation in Cape Town. Abalimi provides support services such as supply of low-cost bulk compost, seed, seedlings, training and on-site project extension. Abalimi's two non-profit People's Garden Centres annually supply agriculture and horticulture inputs to, on average, 2,000-3,000 home-based survival and subsistence gardeners and approximately 200 community agriculture and greening projects. Abalimi projects are encouraged to be 100 percent organic. The economic potential for community agriculture is significant, as there is a high and ever-growing demand for organic vegetables in Cape Town. Organic markets and retailers both large and small are always undersupplied. There is now an increasingly organised community-based organic farming and gardening movement, led by associations such as the Vukuzenzela Urban Farmers Association (VUFA), which is supported by Abalimi¹.

SCAGA

The Siyazama Community Allotment Garden Association (SCAGA) is a member of VUFA. Since 1997 its members have farmed 5,000 m2 in a corridor previously under power lines (low-intensity feeder lines that were later decomissioned) in Macassar, Khayelithsa. SCAGA could provide 3-4 permanent full-time formal jobs, but decided instead to become a Livelihood Level garden, with up to 30 subsistence "jobs", on a mixture of individual and communal plots. These form the centre around which a number of other entrepreneurial and service initiatives have been or are being developed. In SCAGA's case, a small seedling nursery, a craft group, and a tea and catering service have been developed, with future plans for a soup kitchen and child care facilities. Adjacent land within the same servitude corridor – some 3 hectares of sandy wasteland – has now been fenced and is being developed to accommodate another 200-300 gardeners.

SCAGA Garden how it looked before

Each SCAGA member receives a minimum cash and food income, after costs, of R50-R100 per month (US $ 7-14), a lifeline to households with no discernable income. In 2005, the project hosted its fifth group of 30 people successfully marketing high-quality organic produce. Group savings at year end, after costs and own consumption, have varied between R2,000-R 20,000.

This community oriented project of SCAGA has had far-reaching impacts, both within the local community and on policy development in Cape Town. It has sparked hundreds of applications from new groups and has given planners solid proof to argue for community-managed open spaces and for self-help job creation. SCAGA is repeatedly visited by VIPs, including local government Ministers and senior officials. The Western Cape Department of Agriculture (in contrast to its national counterpart) has recently begun to give some solid support to community organic agriculture projects, mainly in the form of improved infrastructure.

Impacts on the local environment have also been quite substantial. Soil fertility inputs have decreased, while pests, once a headache, are hardly mentioned now. Improved health is also becoming evident, as are the medicinal use of fresh organic food for immune system building and the all-purpose therapeutic value of organic growing. New members often come with signs of malnourishment. They have low energy and little money. After one season, frequent remarks on all-round health improvement are often heard.

There have also been positive impacts on the position and role of women as leaders, through, for example, Ilima - traditional mutual-help work events. These have now become a practical tool in women's empowerment and mobilisation, facilitating to obtain community support and muscle power for SCAGA projects. It began with SCAGA women recruiting unemployed men to do heavy work by re-introducing a traditional rural practice – serving of traditional beer and food after the work is done. These events cost very little, but more importantly the women earn wide respect and support in the community by the work they do. SCAGA is now firmly women-led, and women-run projects are now the norm. On occasion, male SCAGA members, offer time to activities (without the women's additional responsibility of managing households). But friction arises whenever the men insist that all the food produced has to be sold. Such problems are now being minimised as female leadership is accepted. It has recently been decided that SCAGA men, while needed for the heavy work, should run their own gardens separately!

And SCAGA Garden how it has changed

New developments

There have been two recent developments. First, a unique Development Continuum with measurements for project sustainability has evolved from actual field experience and is in the process of finalisation (see Figure 6.1). This continuum and measurement system tracks the development of community agriculture projects through four levels: from Survival, through Subsistence, into Livelihood and then to Commercial. The continuum takes into account social dynamics such as group conflicts and the "flow-through" of members, enabling these to become positive events rather than limiting factors. It is now known that new groups need about seven years to establish a relatively stable organisation for community agriculture, while sustainable-level skills and knowledge takes approximately three years to acquire within each level. The physical infrastructure for community agriculture, in contrast, can be delivered within one year – the exception being fertile soil.

The other new development, the Livelihood Garden, is a subsistence level garden with a commercial component that anchors several social and economic initiatives of the gardeners. These include crafts and refreshments for visitors and tourists, child care and soup kitchens (partly-funded by government grants) for the sick and needy, and seedling nurseries for the gardeners' use and for sale to others. In this way, garden activities become multi-functional entrepreneurial and community support initiatives.

To further extend the community development potential of SCAGA, Abalimi's organisation building arm uses tried and tested interventions to build farmer and gardener skills and organisational capacity (since 2000). Horizontal learning (farmer to farmer) exchange, action learning and savings mobilisation are key development activities in enabling development. Micro-credit to groups with consistent savings records will be available in the near future to projects entering the Livelihood and Commercial levels of the Development Continuum. Periodic farmers markets, tunnel greenhouses, cold-storage rooms and value-adding packing sheds will follow in the next years, supplying a wide range of produce for cooperative marketing and creating new livelihood and job opportunities for the poor. Organic certification is now being sought, whereby Abalimi and VUFA will obtain "bulk certification". Association members will then obtain certification more cheaply and thereby increase the external marketability of their products.

Figure 6.1 The Sustainable Development Continuum for Organic Micro Farming Projects

Abalimi is also determined to ensure that organic certification will not act as a deterrent to emerging players. It is developing a Master Gardeners training programme that, once accredited, will enable illiterate gardeners and farmers to move from Survival through Commercial development levels. This will also form the basis of a capacity building programme enabling genuine organic farmers to return to abandoned Eastern Cape lands.

The social impulse behind SCAGA, combined with its relative economic success to date, is South Africa's first example of sustainable urban community organic farming as a permanent lifestyle choice. Consistent with the best intentions of community development, there is no limit to what can be achieved by Cape Town's urban farmers once they find ways to work again on the land with trust and goodwill.

Note

¹VUFA is currently networking with other emerging small farmer formations provincially. Abalimi assists VUFA in enhancing its national and regional links. It is hoped that, over time, the emerging national and regional organic small and micro-farmers associations will federate in order to leverage increased benefits to the poor. www.abalimi.org.za

Troy Gardens, Madison, Wisconsin USA

Martin Bailkey

In 1995, the State of Wisconsin offered for sale 6 hectares of former farmland on the north side of Madison, the state capital. For several years, a local anti-poverty NGO had been permitted to manage community garden plots on the site, with gardeners drawn from both the surrounding neighbourhood and elsewhere in Madison. Upon hearing of the state's wish to sell the land, gardeners and neighbours who valued the implicit quality of the site as informal public open space, organised to develop a strategy for keeping the rural character of the property. This began a 6-year effort that resulted in the sale of Troy Gardens (named after Troy Drive, which borders the land) – and to which the state added an adjacent 6 hectares – to the Madison Area Community Land Trust (MACLT) in 2001. MACLT now leases 10 hectares to the Friends of Troy Gardens (FTG) as undeveloped conservation land that will, by mutual and legal agreement, remain as open space for the community's benefit, and will build 30 residential units on the remaining land under the co-housing model (see www.cohousing.org). MACLT will price 20 of these units at levels affordable to lower-income home buyers, in keeping with its organisational mission to make housing affordable in Madison's increasingly expensive real estate market. For their part, FTG, a membership organisation run by a board of directors composed of community members, manages the different community-oriented programmes occurring on the site throughout the year.

Children proudly display the vegetables grown in the Kid's Garden program at Troy Gardens.

From its beginnings as a citizen reaction to the state's plan to sell the land, Troy Gardens has been marked by active community involvement. The existing community gardens established urban agriculture as a key component of the community's vision for Troy Gardens, and ideas for involving stakeholders with urban farming evolved over the years of discussion and planning. Part of the richness of Troy Gardens is based upon the fact that these stakeholders are not drawn from a single social group, but include middle- and upper-middle class whites, a strong community of Hmong refugees from Laos and Southeast Asia, local school-age youth, and smaller groups of African-Americans and Hispanics. Today, Troy Gardens forms a rich display of community-based urban agriculture, both in form and in culture. About one-half of the almost 300 community garden plots of 50m² are efficiently farmed by Hmong families, who typically grow high quantities of indigenous vegetables. The remaining garden plots are equally divided into an organic, non-tilled section and a section tilled before each growing season.

A short distance away from the community garden plots, past the displays of edible and Hmong medicinal plants, and past the 2 hectares of tall-grass prairie now being restored by community volunteers, sits Madison's first urban farm for larger-scale production. This 2-hectare community supported agriculture (CSA) farm completed its fourth year of operation in 2005. Under the CSA structure, individuals and families purchasing a share in the Troy Gardens farm prior to the growing season receive a steady supply of fresh, certified organic produce from June into October. There were 89 shareholders in 2005; of these 9 were worker shares (discounted shares for those doing significant farm work) and 4 were shares for low-income families, subsidised through outside donations of money. In addition to distribution through CSA shares, the Troy farm sold fresh produce once a week at an on-site market stand, and at two Madison farmers' markets. Produce was also sold at Madison's leading cooperative grocery. The farm generated an income of US$ 54,700 in 2005, and FTG, the farm's manager, projects an increase to over US$ 65,000 in 2006.

Multiple functions

The food production activities at Troy Gardens provide the framework for a rich variety of community-building activities. In addition to the daily sharing of experience among the community gardeners and CSA farm workers and volunteers, a number of programmes reach out directly to schoolchildren and high school students from Madison's north side. The successful Farm and Field programme offers job training and other skills to high school students aged 14-17 each summer through exposure to ecological restoration, organic farming and the marketing of farm products. And the Kid's Garden programme provides gardening, arts, nutrition, cultural and environmental education to children from the area's primary schools. The programme is designed to coordinate school curricula with on-site activities at Troy Gardens. The children plant and maintain their own garden beds and participate in arts and crafts projects that enhance the garden's appearance. Food grown in the Kid's Garden is brought home to participants' families, used for cooking lessons or donated to community centres and food pantries. In addition to youth activities Troy Gardens hosts several public events tied to the seasons, including a Savour the Summer Festival in August and a Harvest Festival in autumn. Whilst being a celebration of food and the changing seasons (important in the northern climate of Wisconsin), these events are enhanced by performances of Hmong music and dancing.

High schools students learn sustainable urban agriculture methods through the Troy Gardens Field and Farm project.

The permanence of Troy Gardens is a testament to the ability of several Madison NGOs with different missions to find common ground and work together on behalf of Madison's north side community, independent from significant government involvement. The community land trust model has been a valuable tool in ensuring that the acquisition of the land from the state occurs in the best interest of the surrounding neighbourhood (Caton Campbell and Salus 2003). Faculty and students from the University of Wisconsin-Madison managed to overcome community concerns that they would impose their own agendas and have become valued players in, among other roles, developing the Troy Gardens site plan, guiding the prairie restoration and improving the productivity of the CSA farm. Recently, as a way to introduce the local Hispanic community to Troy Gardens, the University helped FTG develop a production and marketing plan for huitlacoche, a naturally occurring corn fungus that has been a delicacy in Mexican cuisine for centuries.

Challenges

As with many similar projects, the success of Troy Gardens as an example of Community-Based Urban agriculture (CBUA) is balanced by several challenges. With no direct government support, Troy Gardens, like so many similar CBUA activities in the US, is dependent on grants and donations. The small FTG staff must thus spend significant amounts of time and energy seeking funds to continue basic operations. A second challenge has been to broaden the ethnic diversity of Troy Gardens' users. Apart from those participating in the youth programmes, the involvement of the surrounding Hispanic and African-American communities remains low, despite a number of outreach efforts. Finally, with the maturity of Troy Gardens as a coordinated series of community-based activities, the boundaries of its "community" are sometimes blurred. In most regards, Troy Gardens remains solidly-rooted in Madison's north side. Yet it is increasingly seen as a valuable amenity to the entire city of Madison. Given this perception, Troy Gardens' leadership has discussed the possibility of applying its community-building expertise in other Madison neighbourhoods, particularly those with low-income residents.

Troy Gardens was born under special circumstances. But hard work among dedicated community members, combined with outside involvement by individuals respectful of keeping ownership within Madison's north side community, has resulted in an exemplary model of CBUA – one that combines urban agriculture with other activities to form an integrated set of place-centred community-building practices.

The Troy Gardens farmer leads one of the many tour groups that visit the urban CSA farm each growing season

Reference

Caton Campbell, Marcia and Danielle A. Salus. 2003. Community and Conservation Land Trusts as Unlikely Partners? The Case of Troy Gardens, Madison, Wisconsin. Land Use Policy 20: 169-180.

Project 'Patio Comunitario': a community initiative to produce sustainable food

Justo Torres Lazo
Francisco Paz Barada

Background

The project "Patio Communitario" addresses the issue of access to food, which is one of the most severe problems impacting the quality of life of the Cuban population. The elderly, women, housewives, and children are the groups most affected by this problem. This lack of access to sufficient food has its origin in the economic crisis known as 'período especial' (special period) in Cuba in the late eighties, early nineties. The U.S. blockade and the disintegration of the European Socialist Block (that always supported Cuba before) made the Cuban government redirect the country's food production strategy towards organic production. It also provided greater entitlement of land to the people by forming new cooperative organisations known as 'Unidades Básicas de Producción Cooperativa' (basic units of cooperative production).

In Cuba's urban areas, agricultural activity has increased through 'organopónicos', (intensive organic gardens), state agricultural enterprises and small plots cultivated by individuals or labour centres. This redirection of urban activities has resulted in the ability to maintain an acceptable level of food products in the lunchrooms of schools, kindergartens and labour centres and in farmers markets. However, in spite of these advances, it has not been possible to provide food at reasonable prices to the majority of Cuban families.

One of the neighbours is harvesting from the patio garden

In Cuba, and particularly in the city of Havana, the resources designated for collection, transportation and disposal of urban waste have been significantly reduced during the crisis years. The situation has now become critical in terms of the risks to human health and the environment due to an increase of uncontrolled garbage dumps that have sprung up everywhere. The number of reported environment-related illnesses has increased. Respiratory diseases, allergies, intestinal diseases and recent epidemics of dengue are amongst these. Studies have revealed that about 60 percent of all household waste comprises of organic material (see chapter 8). Such a high volume of organic waste provides an excellent opportunity to produce organic fertiliser for plants (edible, condimental, medicinal and ornamental) and to provide food for small animals that are authorised to be raised in urban zones.

Canal District in the Cerro municipality

The 'Consejo Popular' (people's council) of the Canal district in Havana is aware of these problems related to waste management. Being one of the oldest neighbourhoods in the city, it has a high density of people living in deteriorating urban infrastructure. Local health statistics indicate a high incidence of environment-related diseases including stress. Community alternatives to deal with this issue and to create a change in the district's culture towards the environment and hygiene hardly exist.

The Canal district has many houses with 'patios' (courtyards) which could be used as spaces to raise animals, to grow fruit trees and gardens of medicinal plants, vegetables and spices. Up to now, the patios have not been used in this way. This provides an opportunity to encourage people to use the patios for small scale organic gardens. People in this district have a high sense of ownership, which makes it easier to develop participatory projects that transform and benefit the neighbourhood.

The 'Taller de Transformación Integral' (Workshop on Integral Transformation – which is an institution of local government in Cuba dedicated to community work) of the Canal district has worked for years in collaboration with the population to support and create various social projects. They are aware of the necessity to take action on the issues mentioned above. And among the inhabitants there is enough knowledge and experience that could be used to jointly find local solutions to the problems.

The project 'Patio Comunitario', created in 1998, has been working for eight years on these topics and promoting urban agriculture within the community and has gained the people's recognition as well as the support of social organisations and the local government.

Main Activities of 'Patio Comunitario'

Household food production

The project 'Patio Comunitario' promotes urban agriculture using permaculture designs in small spaces within houses (courtyards, balconies, flat roofs, gardens, lots, etc.) with the aim of producing vegetables, fruits, spices, medicinal and ornamental plants, and raising rabbits, chicken and guinea pigs. This activity contributes to improving family incomes in two ways: the participants don't have to buy those products which they produce and at the same time earn an extra income by selling the excess harvest to neighbours (mostly fruits). There are currently 20 family gardens in the district involved in the activities of this project. The project also aims to recover plant varieties that were traditionally used in Cuban kitchens, but have become scarce or are in danger of extinction. Chayote, Ñame, and Caimito (Cuban vegetables) are a few examples.

Recycling domestic waste

Another activity of this project is the recycling and reuse of a significant volume of the solid organic waste generated in households. This includes kitchen food waste used in vermiculture systems, for compost making and feeding small animals, and other waste such as boxes, bags, old tyres, car batteries, wash basins, containers etc. which are filled with soil and used as planting receptacles. Reusing waste in this manner diminishes environmental pollution and mitigates health risks caused by open waste dumps on the streets.

Environmental education and community training

The neighbourhood environmental education and training component is accomplished by hosting workshops, courses and conferences on a variety of environmental topics. These training courses are held periodically in the demonstration courtyard at the project's headquarters. The project pays special attention to environmental education of young people, who as future citizens would have the responsibility to continue and improve the work accomplished today. At the headquarters of Patio Comunitario, two environmental interest circles (groups) are being hosted. These circles use methods of non-formal education and are attended by 20 of the district's primary school students.

Once a week (on Wednesday) the children learn the importance of living in harmony with the elements of nature. They are confronted with the benefits of the trees, medicinal plants, and different forms of reuse and recycling in the community, while getting to know healthy lifestyle habits and how to contribute to keep the environment of their district and of Havana Bay clean. They receive this knowledge from volunteer instructors who are members of the project management group. The learning process is supported by the pedagogical techniques of 'Educación Popular' (Popular Education), through which the children come to understand the relationship between human beings, nature and society by the collective construction of knowledge and through their everyday experiences. Next to didactic games, drawings, songs and theatrical representations, they take on homework tasks of practical activities at home, in their block or at school, based on what they learn during each meeting. The children participate in preparing and planning these activities.

To support neighbourhood-level environmental education and training, the project has recently set up a Centre of Environmental Community Information. The information centre has a library with resources on the environment and healthy living. Workshops and conferences for plant and animal producers, housewives and children of the community are also being held at the centre.

Healthy Food Fairs

A healthy food fair takes place on every last Saturday of the month at the headquarters of Patio Comunitario and is the activity that generates the highest level of community participation. The fairs are organised by the neighbours with the support of community organisations and the Taller de Transformación Integral of the Canal district. The neighbours cook vegetable dishes and present them to the audience. The winners are selected by a community jury and receive a popularity prize. Specialists give lectures about healthy nutrition and lifestyles. The fair also places emphasis on the community's artistic talents. A children's procession, a painting exhibition and troubadours are among the activities organised that feature in the fairs for the enjoyment of the community.

The healthy food fair combine recreational activities with provision of information.

These fairs in the Canal district of Cerro demonstrate that it is possible to create community-initiated recreational activities which at the same time provide information on a healthy lifestyle. This initiative has allowed 'Patio Comunitario' to promote environmental lifestyle to parts of the population which don't have formal ways of receiving this environmental education, such as housewives and retired people. About 270 people have participated in this activity in the neighbourhood.

These activities have a significant environmental and social impact. They contribute to improving the quality of life in the community as well as to strengthening the cooperation among of all the social actors. These are the first important steps toward making implementation of the Local Agenda 21 in the district a reality. The achievements of this project will be used as good practice examples in the country to realise the dream of constructing sustainable communities that live in harmony with their natural surroundings.

Resources

Farming Inside Cities: Entrepreneurial Urban Agriculture in the United States.
Jerry Kaufman and Martin Bailkey. 2000. Lincoln Institute of Land Policy.
This working paper explores the feasibility of for-market city farming as a means of using vacant parcels in the centre of US cities, particularly those suffering the effects of deindustrialisation. Boston, Philadelphia and Chicago are used as case studies. The authors try to balance the opportunities of urban agriculture, particularly as a tool for community and economic development, with a series of constraints that must be addressed for these opportunities to be realised.

Entrepreneurial Community Gardens: Growing food, skills, jobs and communities.
Feenstra, Gail, Sharyl McGrew and David Campbell. 1999. DANR Publication No. 21578. Davis, CA: University of California Agriculture and Natural Resources
This study focuses on 27 projects in the US that started off as traditional community gardens and added on entrepreneurial components with the intention of increasing their community value. The projects are compared on a number of aspects: site characteristics, production and marketing models, participants and employment generated, levels of economic self-sufficiency, and other individual and community benefits.

CitiesPeoplePlanet
Herbert Girardet. 2004, Wiley-Academy
This book is of interest to any practitioner or policy maker involved in urban agriculture. In chapter 12, "Relearning Urban Agriculture", the author discusses the beginnings of urban agriculture, how it has developed through history and from developing countries to the USA.

Continuous Productive Urban Landscapes: Designing Urban Agriculture for Sustainable Cities
Edited by A. Viljoen, 2004. Architecture Research Unit, University of North London, U.K. ISBN 0750655437
This book takes an architectural perspective on urban agriculture. It proposes a design for a new kind of sustainable urban landscape. The innovative concepts put forward in this book have substantial potential to enhance the future quality of life within our cities. The book is well illustrated with lots of photos, diagrams, maps and tables.

Agriculture in the City, 2001 Maria Caridad Cruz & R, Sanchez Medina, IDRC
In the 1990s Cuba instituted a food programme that included urban agriculture and farming in the city. Free markets were reinstated, production coops were linked with markets, land was redistributed and areas under export crops were converted to domestic food crops. This book describes Cuba's urban agriculture programme and could be of particular interest to municipal, local and community authorities.

Gardens of Hope, Urban Micro-farming and HIV/Aids
De Zeeuw H. ETC Urban Agriculture, Abalimi and CTA.
ETC-Urban Agriculture in cooperation with Abalimi Bezekhaya (Cape Town) and the financial support of CTA (the Netherlands) organised a study visit cum workshop in South Africa (Johannesburg and Cape Town) on "Micro-farming and HIV-Aids" in August 2005. Twenty persons/organisations from Southern and Eastern Africa participated in the study visit/workshop and shared their experiences. The proceedings of this event are available at www.ruaf.org, and also published on this DVD.

www.foodsecurity.org/list.html
The COMFOOD listserver is a primary link between individuals and organisations addressing community food security in the US, Canada and globally. The listserver hosts discussions on current food security issues and announcements of relevant projects, conferences, articles, etc.

www.city.toronto.on.ca/health/tfpc_index.htm
A completely refurbished website with links to, among others, the Toronto New Food Charter and the "Growing Season" report by the Food and Hunger Action Committee of the City of Toronto.

www.eco-farm.org
The Ecological Farming Association, formerly the Committee for Sustainable Agriculture, is a non-profit educational organisation that promotes ecologically sound agriculture.

www.cbnrm.net
The Community-Based Natural Resource Management Network's web site provides a powerful set of broad, robust and useful networking tools aimed at linking stakeholders.

www.worldhungeryear.org/fslc
This online Food Security Learning Centre is created to provide site visitors "with an in-depth look at common hunger and poverty issues facing many U.S. communities." It contains subject categories on Family Farms and Nutrition, and subcategories such as Community Supported Agriculture, Community Gardens, Food Policy Councils, Farmers' Markets, Farm to Cafeteria, and more.

This chapter deals with the socio-economic impact of urban agriculture on income generation, poverty alleviation, urban food supply, livelihoods, as well as indirect costs and benefits for society including environmental externalities. Two levels of analysis are considered to assess this impact: the household and the city. The assessment of social and economic impact at the city level suffers more from lack of data than is the case at the household level. A main question is whether urban agriculture should be seen as an informal, residual, subsistence activity or as one that can shift from simple to enlarged reproduction of urban food, by making the best of its proximity to urban consumers and sustaining incomes in the long run.

Local Economic Development and Marketing of Urban Produced Food

Paule Moustier
George Danso

State of debates

If urban agriculture is attracting the growing attention of researchers, policy makers and diverse development stakeholders, it is mostly because it provides some answers to the unique social, economic and environmental challenges posed by fast urban growth (see also the preceding chapters). The dramatic speed of urban growth in developing countries has not been paralleled with the development of enterprises and infrastructure needed to absorb the new employment needs, by contrast to the developed countries where urban development has been much slower (Henderson, 2002). Finally, the context of fast liberalisation and restrictions in the public sector has reduced the possibilities of employment in public administration, traditionally a major provider of employment in cities.

A night wholesale market in Hanoi

Yet, peri-urban agriculture is still a subject of debate as regards its viability and the necessity for it to receive political support. In a challenging paper, Ellis and Sumberg (1998) provide a number of reasons why scarce public resources should not target urban agriculture. The report stresses that in the light of high land costs in urban areas and the fact that there is still not enough land to cater for housing and infrastructure needs, it would seem legitimate to let agriculture move towards rural areas whilst improving the transport infrastructure at the same time, as has been the case in Europe. Moreover, urban agriculture is subjected to many types of pollution and is itself a pollutant. In fact, urban agriculture takes advantage of market distortions and can be only transient. But most to the point, the authors looked at the lack of rigorous quantitative data to assess the social, economic and environmental impact of urban agriculture, and compare it with alternative sources of incomes in the city, alternative uses of land, and alternative sources of food.

In her analysis of the case studies prepared for the ETC Reader on urban agriculture in 2000, Rachel Nugent also points out the informal, small-scale character of UA, and its little impact in terms of income injection into the economy: "agriculture is a residual activity within imperfect markets. As such, it is conducted opportunistically and with relatively little investment. Farmers are more induced in self-subsistence rather than looking at income opportunities" (Nugent, 2000) The survival strategies of urban farmers has also been brought to the fore by Lipton (1977) as part of his famous "urban bias" theory in which he describes urban producers as "fringe villagers, waiting until penury forces them back to the land and meanwhile living on casual work or on their rural relatives". In fact, UA is often presented with the characteristics found typical of the informal sector, which have been summarised by Cole and Fayissa (1991) as small size, family management, labour intensiveness and extra-legal nature. These characteristics generate what economists call the simple reproduction of the enterprise, i.e. the impossibility to generate more than the income necessary for the enterprise to pay for the inputs and means of production involved, and hence the impossibility for the enterprise to accumulate savings and invest in its development. This process has been particularly well described by a series of studies on UA in Zambia (Rakodi, 1988; Jaeger and Huckabay, 1984): poor gardeners are caught up in a vicious circle when they plant a garden because their jobs do not provide them with enough cash income to feed their family, and they cannot grow more food and thus save money because they do not have cash to buy agricultural inputs, eg., manure, wastes or fertilisers...a typical poverty trap.

Women sell part of their produce at the market of Los Chillos in Quito, Ecuador

Yet, as discussed in chapters 1 and 4, empirical data on urban agriculture generated in the last ten years helps analysts to go beyond the image of the subsistence farmer as the dominant type in urban agriculture. The number of case studies on urban and peri-urban agriculture has increased rapidly and are a comprehensive and valuable source in evaluating the economic and market role and comparative advantage of farming in and around cities. The methods, both in terms of conceptual frameworks and data collection, have improved to take better account of the specific features of urban agriculture, especially its numerous non-market costs and benefits, as well as its non-market organisational features based on the logic of location and risk alleviation, for which economics of proximity, combining insights from spatial and institutional economics, provide relevant analytical tools. While a frequent focus of prior studies has been the opposition between the informal urban agricultural sector and the urban environment, particularly in terms of policy, the benefits of alliances between agriculture and the urban environment are given more attention now, and a more balanced appreciation of the conflicts and synergies is looked for (Van den Berg et al., forthcoming). It is only through such alliances that urban agriculture can break out of the transient remains of rural agriculture and really gain an "urban nature" as expressed by Donadieu and Fleury (1997).

Urban Agriculture and Livelihood Strategies

Diversity of livelihood strategies

According to UNDP (1996), 80 percent of families in Libreville (Congo), 68 percent of urban dwellers in six Tanzanian cities, 45 percent in Lusaka (Zambia), 37 percent in Maputo (Mozambique), 36 percent in Ouagadougou (Burkina Faso), 35 percent in Yaounde (Cameroon) are involved in urban agriculture. The involvement of so many people in urban agriculture indicates its centrality amongst informal-sector activities (Obosu-Mensah, 1999). Yet the reasons for getting involved in urban agriculture, and consequently, its social and economic impact, vary across different categories of households. A major feature of UA is indeed the diversity of the socio-economic profiles of actors involved, and their varying income and livelihood strategies. Thus, the valuation of socio-economic impact will be different according to the types that are referred to, and not taking this into consideration may lead to differing estimates. Several attempts to classify urban agricultural systems have been made (Bakker et al., 2000; Smith, 1999; Moustier et al., 1999) which can be summarised into the types below and of which the characteristics are found in Table 7.1 (additional types could be added including hobby farmers or speculators).

1. Subsistence home intra-urban farmers (intra-urban and peri-urban areas)
    
2. Family-type commercial farmers (intra-urban and peri-urban areas)
    
3. Urban and peri-urban agricultural entrepreneurs (intra-urban and peri-urban areas)
    
4. Multi-cropping peri-urban farmers (peri-urban areas)

The proportions may be different elsewhere. In East Africa the subsistence type may be more significant due to the availability of more vacant space within cities. In Latin America and Asia, the types definitely differ across cities.

Subsistence home (intra-) urban farmers

This category involves urban residents who farm around their homes or elsewhere near the city, mostly for subsistence purposes. They raise staple food crops, vegetables, small livestock, and sometimes trees. Drechsel et al., 2004) documents that every second household is engaged in some form of subsistence production in Accra, Ghana. The production is typically seasonal, and the output is used mainly for home consumption, in addition to market purchases. There may also be the occasional sale of the surplus in the market. These survival strategies have been documented by a number of case studies including the ones reviewed by Nugent (2000). Typical examples are maize growing in the districts of Yaoundé, Accra metropolis and Harare; rice growing in Tamale, Ghana and Bandim, Bissau (Armar-Klemesu, 2000; Danso et al., 2002a; Lindell,1995); and multi-cropped fields cultivated seasonally by elderly women in Brazzaville on the outskirts of the city. Food from subsistence type production is usually of better quality, lower in cost and is more consistently accessible than purchased food (Gerstl, 2001).

Strategies of family-type commercial farmers

Family-type commercial farmers appear to be the dominant type in terms of importance in urban food supply, if not in terms of numbers. The typical crops grown are vegetables. What these farmers have in common is a family background in agriculture, which may also be in relation to ethnicity. For instance in Buenos Aires where the vegetable growers are mostly Bolivian, the Japanese mostly grow herbs and the Italians grow trees (Craig et al., 2002). Another common feature of these farmers is that they have searched for alternative employment having experienced failures in their studies or former employment; this also reflects the difficult employment situation in African cities, especially for poorly qualified people. Three-fourths of the interviewed vegetable growers in Brazzaville mentioned failures in other jobs as mechanics, taxi drivers, cooks etc. before getting into agriculture. Urban agriculture thus enables the employment of urban people who are quite vulnerable from an economic point of view – yet not as vulnerable as the subsistence farmers. But the activity seldom generates enough income for savings and investment, all the more since access to land is insecure.

Retail vegetable trade in Hanoi

In contrast with subsistence urban farmers, who mainly produce for self-consumption, commercial urban and peri-urban farmers are involved in agriculture to earn a monetary income to pay for the numerous expenses in an urban environment (housing, children's schooling, medical expenses). Although they may consume some of their produce, it is only a small portion. Agriculture represents their main household source of income, which may be in addition to other sources of income. In Yaoundé, more than 70 percent of intra-urban farmers do not have other occupations (Temple-Boyer, 2002); this figure is 85 percent in Abidjan (Yappi Affou, 1999). In Yaoundé, again, 70 percent of commercial producers cited agriculture as their principal source of income, 21 percent cited a job in the formal sector and the remaining 9 percent cited petty commerce. By contrast to these figures, 67 percent of household food producers cited a formal sector job as their principal source of income, 20 percent cited petty commerce, and the remaining 13 percent cited their pension. While none cited agriculture as their principal income source, approximately half did say it was their second most important source of revenue (Gockowsky et al., 2004).

In peri-urban Hanoi, alongside commerce and craft work, agriculture still provides more than half of the incomes in a municipality such as Trung Trac (Lecostey and Malvezin, 2001). Forty four of 100 farmers surveyed in Cagayan de Ore, Philippines, indicated vegetable production as their main source of livelihood (Potutan, 1998).

As the farmers' objectives are to get regular food and income and secure their livelihoods, the cropping system has to be risk averse, yet have high value crops to cope with small size of land. This is typically the case of leafy vegetables (see also section 7.4 and chapter 11), which are hardly sensitive to water excesses or shortages and to diseases. Their short cycles (two to three weeks) enable regular cash generation. The proportion of leafy vegetables in the cultivated area is 70 percent in Brazzaville (Moustier, 1996). In Yaoundé (Gockowsky et al., 2004), the focus on traditional leafy vegetables and green maize production is observed among both commercial producers and household food producers.

Production systems of this category display common characteristics: irrigation, use of organic matter, cultivation on beds, and small farm size (less than 1ha). This reflects the necessary intensification per unit of land in a context of high pressure on land. As the farmers have differentiated access to land and capital (the higher the capital, the higher the presence of men in the business), the production systems display variations in the following aspects: the nature of crops grown (low-risk and short cycle crops, eg. leafy vegetables, versus more risky and longer cycle crops, eg. temperate vegetables or ornamental crops); the nature of agricultural inputs; equipment; marketing strategies. The intensification strategies of vegetable farmers have been especially well documented in Kumasi, Ghana by Danso et al.,2002b (see the Kumasi case). Depending on the availability of land, type of production system and location of the farm, the labour requirement differs. In the urban areas, where plot sizes are small, domestic labour is enough to cultivate the land area. In most peri-urban areas, hired, permanent and domestic labour is employed, depending on the above mentioned factors. As the main objective is to get a continuous income, the farmers may change plots and type of crops according to the time of the year. This may give an appearance of seasonality and discontinuity in the farmers' business, but in fact the activity usually continues, although at various locations. While in the dry season, vegetables are grown along the rivers and polluted streams, and with water from dugout wells, shallow groundwater and pipe borne water, farmers may move to non-flooded areas during the rainy season. This was observed in Brazzaville and Bangui where farmers have access to sloping land enabling them mover to higher ground to cope with flooding. In Bissau, on the other hand, women farmers had access only to plots located along the river (the non flooded plots were cultivated by civil servants) and they had to stop growing vegetables in the rainy season, which also explained their limited income (Moustier, et al., 2001).

Urban Agricultural Entrepreneurs

The main differences between this category and the family commercial farmers are the scale of the farms and the use of salaried labour. Urban entrepreneurs, usually civil servants, businessmen or expatriates, invest in intensive temperate vegetable production, poultry keeping, fish farms, or fruit growing, often in combination or with income form other sources. They invest in infrastructure such as motor pumps, treadle pumps, shelters, buildings, and attempt at mechanising certain agricultural operations, eg. irrigation or land tillage. They rely on a salaried labour force for doing most of the tasks. They may lack an agricultural background and the cases of losses and failures are numerous. They often control the marketing of their produce, eg. through direct delivery to stores or with links to export companies. Some examples of this category are the producers of green beans around Dakar, the civil servants involved in fruit production around Yaoundé, the chicken farmers around Ouagadougou and the poultry producers in and around Kumasi. In peri-urban Hanoi, the possibility of access to capital leads to land accumulation and other, non-agricultural, activities. This additional income is invested in agricultural diversification (moving away from rice cultivation to fish-farming, arboriculture etc.) or commerce (Lecostey and Malvezin, 2001).

A supermarket shelf in Hanoi

Multi-cropping Peri-urban Farmers

This category refers to farmers who share many of the characteristics of rural farmers (and may be called "rurban" farmers), except for the influence of the city in terms of production outlets with a growing share of marketed output; sources of incomes, including agricultural and non agricultural; level of intensification; and specialisation (eg. having some vegetable fields). They are hardly threatened by urbanisation in terms of land pressure. This category of has been extensively studied in Cameroon IITA. The study reveals that agriculture is often only one of diverse options to generate food and income. Also see the case on Kumasi by Danso et al.).

Dynamics of change

Suoshi, small park in horticultural production base

An important question of course is whether an urban farmer develops from one category to another? Is it possible for a farmer to evolve from being a subsistence type to a more commercial type, generate sufficient income and savings to increase the scale of business, and even move on to being an entrepreneurial type? The observation that most entrepreneurs originate from sectors other than agriculture suggests that commercial family farmers find it difficult to increase their scale of enterprise, and that they reach little more than to maintain (reproduce) their livelihood. This is due to a trap in terms of farm size and available capital, common to many enterprises of the informal sector, viewed as refuge options rather than paths for development. Yet there are some examples suggesting possible avenues for dynamic accumulation and growth from UA. Vegetable farmers in Lome and Cotonou have moved from subsistence to commercial vegetable production, as their savings enabled them to use treadle pumps and then motor pumps, and most of them are now producing for export and local consumption (Keraita et al., 2003). In Kenya, contractual farming agreements with livestock agro-industries has enabled farmers to generate substantial incomes (Mireri, 2002). The initial conditions for farmers to enter into such a contract are space (being able to accommodate 300 chicks), the ability to pay for the costs for water, electricity, labour and basic equipment, and the payment of a deposit of US$ 0,8 per chick. A supporting system in terms of municipal legislation, technical skill development and credit provision is crucial for these patterns of accumulation.

Interestingly, although they are often documented as a necessary condition for farmers to gain easier access to resources, markets and investment, farmers' organisations are rarely documented as successful in paving the way for economic development (see also the section on food markets).

Evaluating Economic Impact

Methodology

Reliable statistics on farmers' incomes are rare due to difficulties such as the diversity of farmers' profiles, seasonality of crops, continuous harvesting of crops (vegetables), scattering of plots and multi-cropping. Establishing a typology of urban farmers and traders and monitoring their incomes is suggested as a means of overcoming this problem. The typology of farmers should account for the variability of incomes in relation to land size, type of products, age, sources of incomes, etc. (see previous section). The typology of traders should account for the variability of incomes in relation to the position in the marketing chain (wholesaler or retailer), the nature of commodities, and the type of customers (popular versus wealthy), all of which vary according to the location of the market. Farmers' and traders' incomes should be monitored at different times of the year, ideally every month, to take account of the harvests of short-cycle leafy vegetables, or at least during two seasons, the season of maximum harvest (usually, the dry season); and the season of minimum harvest (usually, the rainy season).

In order to assess whether engaging in urban agriculture is a valuable opportunity for urban residents, it is necessary to find references for comparison. In terms of its role in supporting livelihoods, the income from urban agriculture should be compared with the budget necessary to provide for basic food, clothing, and housing expenses in the city. Comparison should also be made with alternative labour opportunities in the city, for varying levels of qualification: for instance, the farming income of a commercial farmer with no qualification can be compared with the income of a cleaner or a guard. The comparison with rural incomes enables to assess the benefits of moving from countryside to city.

Ideally, data on incomes should be computed for one unit of the different factors of production: land, labour, inputs, invested capital, to compare the activity with alternative uses of these factors, in particular for the most crucial such as land. This type of assessment will help to confirm the rationale of urban farmers to invest in crops with the highest returns per unit of land, eg., horticulture and aquaculture. Finally, indicators of risks should be obtained by asking farmers and traders about the variability of incomes (minimum, maximum, standard deviation), within a year and during the five years before.

In order to shift from the household level to the city level, it is necessary to have data on the number of stakeholders involved in farming and trading activities, of the different types, and to extrapolate data gained at the household level using the share of the different types in the total population. The total added value is a useful indicator of the contribution of the sector to the national economy, when compared with the added value of other urban sectors (eg., construction), or to the total urban gross domestic product.

Income from urban farming

A comprehensive overview of monthly farm income from urban agriculture in different cities is presented in Table 7. 2. Case studies conducted by CIRAD between 1989 and 1992 provide interesting estimates of commercial farmers' incomes in comparison to the income necessary for subsistence. In Brazzaville and Bangui, at the time of the surveys, market gardening yielded enough income to provide for the basic food requirements of the family, plus housing, clothing and schooling expenses (Moustier and al, 2004). Hence, even if the total number of farms is small in comparison to the total urban population, their functioning demonstrates that urban agriculture is one of the - too few - sources of stable income that should be protected and considered within a portfolio of other urban cash-earning activities with limited initial capital requirements.

In Kumasi, the incomes of urban farmers occupying open space in low- or bottomlands were estimated at US$ 400 to 800, which is 2-3 times the income they could make in rural farming (see case of Danso, et al 2002). Urban home gardeners in Ouagadougou are able to earn about US$ 4 (direct) and US$24 (indirect) per month. This estimation is comparable to the monthly GNP per capita of Burkina Faso (US$20), one of the lowest in the world (Gerstl.,2001). In Dar es Salaam, Tanzania, incomes generated from urban agriculture were larger than regular salaries of 67 percent of the respondents.

Following the logic of market forces, farmers develop their limited resource - land – by seeking to add highest value.. As the urban pressure on land increases, a change from food crops to market gardening, flower growing or fish farming can be observed. In Bangkok, shrimp farming, which brings in on average 1,400 bahts (US$ 34) per hectare per year, is developing and replacing market gardening that brings in only 200 bahts (US$ 5) per hectare per year, which once replaced rice farming that brought in 40 bahts (US$ 1) per hectare per year (Vagneron et al., 2003). Greater distances from city centres means lower land prices and higher transportation costs; there is an optimal distance at which it is the most economically viable to practise agriculture, in terms of highest added value per hectare, as we can see in Figure 7.1. Around Hanoi, agriculture is most intensive 20 kilometres from town, in Dong Anh and Tu Liem Districts, which gives these areas the highest per hectare added value of 85 MVND/ha (5360 US$/ha).

Note: GNI – General Net Income (UN statistics); n.d. = not determined/reported
Source: Dreschel et al. (2006)

¹ Some reports lack information on the time/period (number of harvests, seasons) the revenues are based on. Only a few valued family labor input and depreciated for investment costs. Data were combined in case of multiple reports per city.

Figure 7.1 Impact of distance from Hanoi on agricultural added value per hectare

Source: Le Duc Thinh (data from 2002, to be published): 1$=15850 VND

Valuation of environmental, social and health impacts

Labelling water convolvulus for supermarkets in Ho Chi Minh City

The field of economics has evolved a great deal in the past ten years to better integrate the value and cost of non-marketed goods. As was pointed out by Pareto in 1906, the value of goods is determined by rarity and need. But the availability versus rarity of goods is not necessarily reflected as a financial cost, because the cost may be delayed in time, or not necessarily easy to measure, or because a market does not exist at all. This is typically the case of health or environmental damages, the costs to the population of which are not directly and immediately paid for. Likewise, the needs for some goods or services are not necessarily translated into a market demand, as is the case of environmental preservation for future generations. Economists refer to these indirect costs and benefits as externalities that cannot be translated into the immediate equation of supply and demand. It is legitimate to try to evaluate the indirect costs and benefits of urban agriculture. Land is sometimes used free-of-charge by urban farmers, either because their presence is tolerated on idle land such as near airports (eg. in Cotonou or Bangui), by the side of main roads (in Nairobi) and under pylons (in Accra, or Cotonou) or because the government has lent some land to them in appreciation of the social role of urban agriculture (in Cuba- Moscow, 1999). But this free use does not mean that the land is of no value to the farmers; in fact, it may actually be a first step towards income generation and becoming capable of paying for more adequate and sustainable land resources. Another typical non-financial benefit of urban agriculture is the role it plays in greening the city, flood proofing and acting as a buffer against urban encroachment. This benefit can also not be captured in direct financial terms.

In order to convince policy-makers of the indirect costs and benefits of urban agriculture, and of the necessary policies to enhance the benefits and reduce the costs, indirect methods of valuation have been tested in certain urban case studies (Henn et al.,2002; Danso et al.,2005). Contingent valuation methods are based on creating shadow markets - simulating shadow situations where people would have to pay for or accept some goods and services and asking people what they would do in such situations.

When damage created (by farming in the city this case) can be repaired (which is not always the case), the costs associated in repairing such damage can provide an estimate of the environmental cost of the damage.

Contingent valuation (CV) has been developed to estimate the users' willingness to pay (for a certain good). A good example of CV is the case study in Cuba (Henn and Henning UAM no.7, 2002) where farmers were asked about their willingness to pay for continuing gardening on their land based on two hypotheses: (i) on their present land; (ii) on land improved in terms of water access and protection from theft. The willingness to pay was appraised by bids, starting from a given amount and then increasing or decreasing it until it reached the acceptable amount. The result is was a value equivalent to 11 percent (without improvement) and 14 percent (with improvement) of their total monthly income, or US$ 344,000 when extrapolated to cover all urban farmers.

In Bangkok, the willingness of farmers to pay for clean water (which is affected by industrial as well as agricultural pollution) was estimated in a similar procedure of decreasing and increasing bids, starting from 1,000 baht per year (US$ 24). The average amount that the farmers are willing to pay for unpolluted water is 1,196 baht/ha/year (US$ 29), and 1,025 baht/ha/year (US$ 34) when including the farmers who are not willing to pay for unpolluted water. The average amount is higher for vegetable (3,200 baht/ha/year=US$ 77) and shrimp (890 baht/ha/year=US$ 21) farmers than for fish farmers (220 baht/ha/year=US$ 5).

Taking account of the indirect costs of environmental damage enables us to have estimates of the economic sustainability of UA for farmers. In Bangkok, when taking into account the costs associated with cleaning the water and making up for soil depletion, shrimp farming the most polluting activity- still remains the most rewarding activity, but the income per family worker reduces by 10,100 baht/year (US$ 242), and growing vegetable becomes slightly more profitable than raising fish (Vagneron et al., 2003).

However, the consistency of contingency evaluation methods may be questioned. Indeed, when asked whether they are ready to pay more to access clean water, most farmers are - at best - sceptical. Paying more for a hypothetical service often seems out of the question since many farmers already struggle to cover their expenses. Declarations from simulations may not reflect the true behaviour in a real situation. Despite its difficulties, this method is still takes us a way forward in making more adequate consideration of the undisclosed costs and benefits of UA to society.

The Integration of UA in Food Markets

The specific role of UA in urban food supply

There are now more balanced approaches in considering the areas (rural or urban) for urban food production. A growing body of evidence supports the complementarity between the two forms of urban food supply. This change in perspective also implies a change in methods in the sense of combining the insights of geography, which helps identify product flows towards urban markets, with spatial economics, which enables a better understanding of the economic reasons behind the location of supply sources, in particular the relationship between the proximity of production and consumption areas and the perishable nature of the products. Substantial study on spatial economics has been done by Von Thünen (1851), and his insights have been commonly used by researchers on peri-urban agriculture. New insights of spatial economics, using inputs from institutional economics and sociology, go even further in the analysis of the influence of market proximity on production characteristics. They transcend the physical attributes of transport, storage or land costs or "physical proximity", and focus on relational proximity, eg. interactions between farmers and market agents, farmers and consumers, and also within the farming community itself.

The revelation of the specific role of UA in urban food supply has also benefited from more rigorous data collection, which recognises that only comparing yearly production and consumption in the city has a number of limitations. These limitations include difficulties in grasping the perishable, seasonal nature of products or not considering the destination of products. Appraising the precise role of UA in urban food supply implies surveys in wholesale and retail markets, and questions on origin and quantities of products traded at different times of the year to take account of seasonal variations. This type of data collection is not easy as, for instance, most fresh products are sold either early in the morning or late in the evening or in the night. When limited by time, such studies should focus on some key products, at least fresh vegetables, as they provide the bulk of what is supplied by urban areas. Increasingly, studies in urban food systems are undertaken in the USA. CIRAD studied food markets in Central Africa and more recently in Vietnam, Laos and Cambodia. SIUPA has also supported the quantification of cassava flows to Yaoundé by an IITA led team, and IDRC has supported similar studies in Ghana via IWMI (Drechsel et al., 2004).

The specific role of UA in the supply of perishable food commodities

Basic food products (cereals or tubers) and dry vegetables (onions) come mostly from rural areas in the country or are imported from abroad. However, current data confirms the importance of UA in the provision of fresh perishable vegetables, mainly leafy vegetables, poultry and dairy products mostly from peri-urban areas (see Table 7.3 for comprehensive data on Kumasi, Ghana and Table 7.4 for various cities in Africa, Asia and Latin America).

* Imported are mainly rice, onions and part of the livestock (meat)

** University farm (same in Accra) Source: Cofie et al., 2003.

Fresh vegetables in this category are mainly leafy vegetables such as amaranth, sorrel, morel, cabbage, lettuce and chives. These vegetables top the list of vegetables consumed, in Africa and in Asia. These vegetables are well known for their short shelf life: after one day they are no longer fresh – and in many countries, freshness is an important criterion for consumers who do not own refrigerators. These leafy vegetables are mostly brought into town from distances of less than 30 kilometres from the city centres, be it in Africa or in Asia. The peri-urban percentage of supply is more than 70 percent.

In Africa, improved broiler chicken, milk and eggs come from city farms or from the suburbs. These farms are run by city dwellers, whereas local beef comes from traditional pastoral or agro-pastoral farms. Urban animal food products are also imported from lower-end European production facilities and pose strong competition to certain local products, such as chicken, despite differences in quality (Guérin, 1998). In Addis Ababa, 20 million litres of non pasteurised milk come from back-yard city farms and are sold directly to the consumer by the producer. Butter, on the other hand, comes from rural areas and from as far away as 650 kilometres from the city (Bonnet and Duteurtre, 1998; Tegegne et al, 1999). In Kumasi, 95 percent of fresh milk consumed in the city is from urban agriculture.

Complementarities in Time

A comparative advantage of (peri) urban agriculture may be in the continuity of product supply, either because of specific natural conditions, or because urban farmers are able to sustain continuous production due to more specialised and irrigated systems - characteristics they may share with some specialised rural areas (the case of Lome and Accra). This is also observed in the dry areas of Mauritania, where peri-urban agriculture is able to supply the market with vegetables on a more continuous basis than the rural areas (Laurent, 1999). In Bangui (David, 1992) and Bissau (David and Moustier, 1993), the share of UA in the vegetable supply increases by 10 percent in the dry season. This comparative advantage is observed especially in the dry season for temperate vegetables, because in the rainy season, the access to non-flooded areas is easier in rural areas. In Hanoi, while 75 percent of tomatoes sold during the cold season are grown less than 30 km from the city, 80 percent of tomatoes sold in the rainy season originate from China and 15 percent from Dalat, located more than 1000 km away from Hanoi (Hoang Bang An et al., 2003).

Sources: (1): Moustier (1999); (2): David, 1992; (3): Mbaye et Moustier, 2000; (4) Dongmo, 1990; (5): David et Moustier, 1995; (6): Laurent, 1999; (7): Jacobi and al (2000); (8): Mbaye and Moustier (2000); (9) and (11): An et al., 2003; and Phuong Anh and al., 2004; (12): Sokhen, Dianika and Moustier (2004); (13): Kethongsa, Khamtanh and Moustier (2004); (14): Yi-Zhang and Zhangen(2000). See also Urban Agriculture Magazine 2002 special edition for world food summit for other figures).

The Advantage of Proximity in Market Organisation

Short marketing chains

Urban products are distributed through very short marketing chains (see figure 7.2). The shortest is direct producer involvement in retail sales: this is the case of 30 percent of all sales in Bangui (David, 1992) and 70 percent of those in Bissau, when private trade had just been legalised (David and Moustier, 1993). More often than not, the producer sells to retailers. This transaction takes place at the field or at night wholesale markets (in Brazzaville, Bangui, Bissau as well as in Hanoi, Phnom Penh or Vientiane – see Moustier and David, 1997; Sokhen et al, 2004; Kethongsa et al, 2004). The quantities collected are small: between 5 to 10 kilos of collected and sold produce per day per retailer/collector in Brazzaville. In Hanoi, more than 40 percent of all wholesale market sellers are also producers; this percentage goes up to 100 percent for water convolvulus. Producers bring 100 to 200 kilos per day to wholesale markets on overloaded bicycles or scooters.

Figure 7.2 Marketing chains for UA and rural agriculture

The strong involvement of farmers, or their relatives, in the processing and marketing of their products, can be termed as vertical integration (see the case of Brazil of PROVE), which has a positive impact on the reduction of transaction costs in the marketing of perishable products, of varying quality standards¹. This involvement in the chain of production is also explained by the small-scale of production and low prices, making it attractive for producers to spend some hours in transportation to get as much as possible of the final price. Yet these characteristics contribute to further fragmentation of the final supply, while economies of scale could be reached by collective marketing. Experiences of collective marketing are hardly developed in peri-urban areas though, or have had little success, given the variability of production in quantity and quality that makes farmers reluctant to "put their eggs in the same basket" as other farmers who may be unsuccessful and pull down the marketing results. Yet there are some successful examples when farmers have shared similar characteristics, and have identified reliable marketing outlets. Examples are the vegetable cooperatives in Hanoi and Ho Chi Minh City, as well as the vegetable farmers' groups in Yaoundé who have organised themselves to sell by a rotation formula. The cooperative horticultural marketing by HOPCOMS in Bangalore is another example (Premchander, 2003 (UAM no.9). Yet such experiences, and especially their economic efficiency in comparison to individual marketing, are not sufficiently documented.

Relational proximity is a common feature of the link between farmers and traders in developing countries, especially for perishable products. This has been documented by a number of research studies on marketing chains from rural as well as peri-urban areas¹. What may be more specific to peri-urban areas is the existence of relational proximity between farmers and consumers, and the possibility of direct links between them, as at farmers' markets where farmers meet consumers directly. These have been especially well documented by Kirwan (2004) in England. In the USA and Europe, urban and peri-urban farmers seek to market their - especially locally grown organic - produce at farmers' markets. The number of farmers' markets in the USA had increased from 1755 to more than 2746 in 1998 – but direct sales from farmers to consumers only represented 0.3 percent of the market value in 1997 (Heller and Keoleian, 2000). In developing countries, direct sales are also observed as a way of promoting organic or IPM vegetables, eg. Farmers' direct delivery to a group of consumers organised in Hanoi and in Phnom Penh with the support of a marketing company and an NGO respectively. This has also been observed among mushroom farmers in Accra who do door-to-door delivery of fresh mushrooms to targeted consumers (Danso et al.,2005).

Low price differential

Short marketing chains contribute to a low price differential for products between farm and final consumption: these account for 30 percent on leafy-vegetables, 35 to 50 percent for cabbage and 75 percent for tomato in Hanoi (Gia B.T., 1999; Son et al., 2002). In rural chains, wholesalers' incomes may be up to ten times higher than that of farmers, but the risks of bankruptcies are higher. Price differentials are higher for rural products due to higher transportation costs and higher wholesalers' margins. While the price differential for peri-urban vegetables in Congo shifted from 1 to 2 from farm to retail, the price differential was 1 to 3 for rural vegetables, 20 to 80 percent of the marketing margin being absorbed in transport costs (Moustier, 1995). And in Havana, Cuba, the prices of tomato, onion, pork and fruit fell from 1 to 3 between 1999 and 1994, the period when the urban agricultural programme was launched (Novo, 2002).

Information on quality and control

The proximity of production areas to consumers, makes it easier for consumers to control quality, and at the same time, keeps producers from cheating on product quality. Most of the supermarkets, shops and restaurants in Hanoi are supplied by three cooperatives located in the peri-urban areas where production along IPM or organic standards is certified by government bodies. Likewise, in Ho Chi Minh City, the cash and carry supermarket is supplied with leafy vegetables by a peri-urban cooperative which gets the support of the department of agriculture and labels their vegetables as safe. Proximity enables frequent contacts between farmers, traders, and consumers and checks on the production process. Proximity between farmers and consumers is not a perfect substitute for independent public control, which is still deficient in Vietnam, but it does reinforce the incentive for farmers not to deceive their customers.

Freshness

In situations of limited access to fridges, freshness of produce is especially valued by urban consumers. In Thiès (Senegal), more than 90 percent of 150 interviewed housewives thought that vegetables should be grown nearby, for freshness and quick access (Broutin et al, 2005). In Vientiane, freshness is the criterion of vegetable choice stated by the highest number of consumers (71 percent out of 100 interviewed, in Potutan et al., 1999). In Hanoi, freshness is the advantage of peri-urban vegetable production cited by 74 percent respondents out of 500 in 2003 (Figuié, 2004).

Enhancing Social and Economic Impact

Acknowledging the multi-functionality of UA

Fields of leafy vegetable basella (Basella alba) covered with straw mulch in Hanoi rural district

Urban agriculture creates landscapes, which is a public good from which users cannot be excluded. This makes urban land management of little interest to the private sector (Donadieu and Fleury, 1997). Urban agriculture produces other things of value to the public: food security, social inclusion and jobs. Within cities, there are other sectors that create landscapes such as parks, to which UA can be linked to and compared with. The advantage of urban agriculture over other 'landscape producers' is that its functioning is supported by market forces, even if these markets are imperfect. It is thus a less expensive landscape producer than a public park. It also provides jobs and social inclusion (esp. Latin America). This multi-functionality of urban agriculture² makes it a 'cheap' producer of public goods. Table 7.5 compares the 'scores' of three urban sectors: industry, public spaces and agriculture in terms of the production of different goods and services. It shows that agriculture gets the highest combined mark. An increased distance between urban centres and agriculture is, however, inevitable if market forces are given a free hand. Hence, from a political economic viewpoint, it is legitimate that the public sector supports UA agriculture. Four areas of support are particularly relevant: integration into urban planning (see Chapter 3); financial support (see Chapter 4), research and extension for more profitable and sustainable intensive commercial vegetable and animal systems (Midmore and Jansen, 2003; Smith et al., 2004; and Chapter 10); and innovative marketing, which will be elaborated in the next section. Municipalities have a crucial role to play in organising such support, in collaboration with national and international programmes.

Source: Moustier (2003); Donadieu and Fleury (1997).

Innovative marketing

Farmers' organisation and information

As established in the previous section, the proximity between production and consumption brings undeniable comparative advantages for marketing yet it also brings some constraints. The small size of gardens and the problems of access to land result in the scattering of plots and the small volumes of transactions. This fragmentation of production (in place and time) makes the circulation of information on market supply difficult among farmers. A solution to this problem is the provision of timely market information to stakeholders: examples are available for Hanoi (see http://www.avrdc.org/susper) and Brazzaville (Moumbélé and Moustier, 1995). A solution to transaction volume is to support farmers' cooperation in terms of marketing to limit market gluts or deficits (see the example of the marketing manager in Ghana). Although farmers' organisations can never completely reduce supply instability, which is mostly generated by the impact of the climate on production, it can nevertheless partly reduce it. It can also generate economies of scale. Farmers' organisation should not be imposed from outside but rather be sought on the basis of existing groups sharing common interests and having developed relationships of trust.

Labelling safe UA products

The internal and external sources of product contamination are manifold in peri-urban areas, but the control of quality is made easier by farm proximity to consumers. Farmers investing in quality control efforts should therefore ensure that their products are recognised by customers as such, so that they can keep customer trust and profit from their investments in maintaining quality.

Some successful examples of peri-urban cooperatives that have developed adequate labelling of their vegetables, based on organic or IPM guidelines, are observed in Vietnam (Hanoi and Ho Chi Minh City). The Van Tri cooperative is an interesting example of successful collective action and vertical integration in the chain. The direct sales of Van Tri vegetables by the producers allow regular contact with the consumers, who ask questions and are given answers concerning the production methods used by the cooperative (Moustier et al., 2005). A similar involvement of a peri-urban farmers' group in the production and marketing of safe vegetables, with the labelling including the origin of product and methods of production, and delivery of a supermarket, is observed in peri-urban Ho Chi Minh City (Phan Thi GiacTam, forthcoming). In Senegal, it is mentioned that in contrast to many industrial producers, urban micro-enterprises may survive by closer contact to consumers through their personalised labels (Fall et al., 2001).

In the Dutch city of Delft, a farmer was able to negotiate a 12-year lease on 35 hectares of land with the municipality thanks to his commitment to producing organic vegetables and milk, and also setting aside five hectares of the land for nature preservation (Deelstra et al., 2001).

Although it does not specifically target urban areas, Prove in Brasil (small agricultural production programme) is a successful example of multi-dimensional programme aimed at developing small-scale enterprises, especially in regards to processing of agricultural products (see case) (Homem de Carvalho, 2001).

Challenges Ahead

Collecting homogeneous and comprehensive impact indicators

The discussion above has shown how difficult it is to get comprehensive indicators of social and economic impact for all the different sectors involved in urban agriculture. The majority of cases mentioned deal with vegetable growing. Subsistence or commercial farming types are usually taken into account. A comprehensive list of indicators, at household and city level, is presented in table 7.6, and could be the basis for collection of data in different cities of Africa, Asia and Latin America. This is especially important in order to convince local, national and international decision-makers on the economic role and viability of UA.

Combining economic and market studies on a commodity chain

Economic studies tend to focus either on farms or on markets, but studies carrying out economic analyses all along the chain from farm to consumption are still limited and should be developed. These studies should provide for a comparative evaluation of rural and urban agriculture in order to show comparative advantages. They should further evaluate the economic impact of successful marketing strategies by farmers including quality promotion. And for these studies to be really meaningful, they should focus on one product that can be supplied by different geographical sources (for a comparison between rural versus urban agriculture, tomato would be a good example), or by different marketing strategies, and they should be carried out at different periods of time to take account of seasonal variations.

Fishing in a pond in Hanoi rural district

Strengthening the analysis of development dynamics and poverty impact

Although the image of urban agriculture has gained more appreciation and moved slightly beyond "subsistence/simple reproduction", there is still insufficient case material on enlarged reproduction, capital accumulation and spill-over effects from innovative commercial farmers. In-depth case studies on the "success stories" of such innovative farmers, who have been able to save up and develop their business, over different time periods, would serve in assessing the viability of these cases and further improving the image of UA.

Appraising the future of neighbourhood agriculture in global commodity chains

The development of international trade, as well as the globalisation of capital in food distribution is now well documented (see in particular Mc Michael, 1984; Reardon and Berdegué, 2002). This creates risks of growing distances between food producers and consumers, and reduced possibilities for citizens to exert control on the way food is produced, i.e. decreased food sovereignty: « From a food-democracy viewpoint, one's right to be fed needs to embrace one's right to feed oneself » (Koc et al., 1999).

Promoting marketing as part of Rosario's UA action plan

Durability of food is developed at the expense of its sustainability (Friedmann, 1994). "More rapidly and deeply than before, transnational agri-food systems disconnect production from consumption and reconstruct them through buying and selling (ibid, p. 272). The pressures to reconstruct regional links between producers and consumers is apparent in many places, whether from economic desperation or from urban politics that place a high priority on ecologically-sound land use and uncontaminated foods than on the social and technical imperatives of mono-cultural farming" (ibid, p. 272 and p. 274). The life cycle assessment of the US food system has shown the lack of sustainability of the system, in particular the high cost of energy involved in transport, packaging and refrigeration: the food system absorbed around 5 percent of the total energy consumption in 1991 (Heller and Keoleian, 2000).

The impact of the development of supermarkets and restaurants on the characteristics of supply chains, including proximity versus distance aspects, needs more attention. As seen in the previous section, the proximity between production and distribution can confer advantages to peri-urban farmers in terms of promoting their product quality, which in itself is an advantage for the supply to supermarkets – if peri-urban farmers can ensure regularity of product supply.

Linking research with local development

Research on urban agriculture requires a long-term involvement in the field because of its informal and unstable character. As urban farmers and traders are generally poor, it is not so easy to collect data from them without rewarding them in return, and it is not always easy to convince them of the long-term benefits of research on the economics of urban farming. At present, the literature on urban agriculture can be schematically categorised in two groups: the works of scholars – especially geographers and more recently economists who try to develop a scientific approach on urban agriculture with explicit research questions and hypotheses, often involving Masters or PhD. students who may have difficulties in gaining continuous reliable data in the field - and the work of practitioners, who are very much involved in the field where try to solve constraints of urban producers through stakeholders' platforms, technical or marketing support – but who may lack the time and skills necessary to carry out rigorous research to evaluate the socio-economic impact of UA and of the innovations in UA. Ideally, teams working on the development of UA should involve people from both research and development (and other stakeholders), be action-oriented and be more concerned with long-term replicability and impact of their work than with one-off assessments which could cause frustration for the UA farmers and for the research community alike. The Cities for the Future Programme of RUAF is seeking to establish working groups in the cities they are working in.

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Economic Impacts of Urban Agriculture in Peri-urban Beijing

Jianming Cai
Zhenshan Yang

In a rapidly changing city like Beijing, urban agriculture covers a diversity of (economic) roles. Not only does agricultural production benefit the producers and consumers directly, it also contributes to city growth and sustainable development.

Who Benefits

Beijing, the capital of China, is facing rapid urbanisation, and undergoing a dramatic transformation. Nearly all activities related to production are moving away from the city centre towards the periphery (the periurban areas). The backbone of the economy is changing, with a dramatic increase of the services sector and a decrease in the importance of the primary industry. This change can also be seen in agriculture. However, the role of agriculture would diminish and its functions in the city economy would depreciate, unless the city of Beijing takes measures to link agricultural activities to the city's development. Many farmers have become farmer entrepreneurs engaging themselves in urban agricultural production and management. Vendors sell urban agricultural products in the streets.

Migrants in Beijing usually sell their vegetables by themselves along the road.

There are at least 2 million urban farmers in Beijing, including migrant farmers. According to official statistics, there were 3.2 million people living in the rural areas of Beijing in 2003, accounting for about 23 percent of its total population. Among this rural population, about 1.7 million are still classified as farmers, involved in farming, forestry, animal husbandry, fisheries, small industries and other commercial activities. Many of the rural youngsters are already full-time industry workers.

Meanwhile, more and more migrants arrive in Beijing, and join the ranks of the so-called "floating population". They come from all over China but have not yet got their household registration status in the city, even though they may have already lived in the city for many years. This situation is changing, but there are still many differences between the floating and local (registered) urban population. The peri-urban areas provide an opportunity for some of this floating population to engage in urban agriculture. This floating population amounted to approximately 4.1 million in 2003 in Beijing, of which about 55.9 percent and 35 precent lived in the inner and outer peri-urban areas respectively. According to author's research, the floating population in peri-urban Beijing increased by 350,000 from 2002 to 2003, with most of these people engaged in UA activities such as agro-tourism and processing of agricultural products.

In general, the economic impact of urban agriculture is multi-faceted, as is shown in the following analysis of three aspects: general city development, UA enterprises growth and farmer household benefit.

General City Development

In 1994, the municipal government officially launched its urban agriculture policy, which focused on six type of agricultural activities, i.e. promoting greenhouse farming, utilising new types of seeds, creating new brands of agri-products, agri-product processing, export agriculture and recreational (sightseeing) agriculture. Since then, Beijing has made notable achievements in its peri-urban development. The agricultural output value has been increasing steadily, but its share in the city's GDP has been declining (see figure 7.3).

Figure 7.3 Agricultural Output Value and Its Contribution to GDP

Source: Beijing Statistical Yearbook 2004.

The percentages of the rural population and agricultural land in Beijing have also got smaller during 1995-2003 (see table 7.8). Yet the output value of agriculture has gained a steady growth. In 2003, the agricultural output value per rural labour unit was RMB 37,554 (equivalent to US$ 4,700), while if other related activities such as rural industries and services are included, the rural gross output value per rural labour unit can be as high as RMB 96,018 (equivalent to US$ 12,000).

The economic structure in peri-urban Beijing has also been changing. Grain and vegetable production used to be the dominate sources of rural income in the 1980s. With the official introduction of urban agriculture in the 1990s, the agricultural economic structure changed dramatically. In 1995, the proportion of agricultural output value for farming, forestry, animal husbandry and the fisheries was 53 percent, 2 percent, 42 percent, and 4 percent respectively, and changed to 37.7 percent, 5.6 percent, 53.3 percent and 4.4 percent respectively in 2003. The market mechanism clearly played a role in this change. Other agricultural related industries also grew, diversifying the agricultural sector even more.

UA is strongly linked to other activities such as transport, construction, commerce and food catering. In fact, the number of agriculture-related labourers in peri-urban Beijing increased from 1,636,000 in 1995 to1,696,000 in 2003, despite the fact that urban Beijing expanded dramatically in this period and the agricultural land reduced. Most of this increase in work is in UA-related sectors such as agro-services, transportation and agro-business.

Source: Beijing Statistical Yearbook 2004. Beijing Municipal Planning Revision (2004-2020, unpublished)

Recent development trends show that urban agriculture in peri-urban Beijing is diversifying both in quantity and quality. In the inner peri-urban areas, more high-level and capital-intensive UA activities, such as agro-tourism, are growing fast, while in outer peri-urban areas, fruit growing and green vegetable production is taking place instead of traditional grain production.

Urban Agricultural Enterprises

In Beijing, the most common urban agriculture-related enterprises are processing and production, agricultural tourism and high-tech agriculture. Apart from mini- and micro-enterprises, there are also some big enterprises engaged in these activities In agricultural production and processing alone, over 940 enterprises are active (statistics of 2005).

From 2000 onwards, agro-tourism has gained momentum, including "sightseeing agriculture" which refers to one-day trips of tourists (visiting and picking activities) and "recreational agriculture", referring to multiple-day stays with accommodation and other tourism-related activities. Many farmers build up sightseeing agricultural gardens by utilising their existing farm land. These easy-access activities have resulted in more than 1,900 sightseeing agricultural gardens in the 300 villages of the 50 towns and townships in peri-urban Beijing. Among these gardens of varied size, there are 285 big enterprises, of which 30 are designed as municipal key gardens. At another level of agro-tourism, recreational resorts make use of resources by integrating agricultural activities with modern recreational experiences, hotels and entertainment. There are now about 155 different resorts in Beijing integrating services such as health care, ecological experiences, folk custom appreciation, etc.

Hi-tech agro-industry is another active area for UA related development in peri-urban Beijing. By the end of 2001, 375 various hi-tech agricultural parks had been constructed. The most famous is Xiaotangshan High Tech Demonstration Agricultural Park, which is a national level park. Besides this, there are six other hi-tech agricultural parks constructed by the Ministry of Chinese Technology & Science and 25 agro-industrial parks sponsored by the Beijing municipal government.

As illustrated in Table 7.8, UA enterprises in peri-urban areas are quite lucrative with a high income ratio. In fact, all UA related enterprises make more money than enterprises in other sectors, such as services and manufacturing. This was particularly true since 2002, when UA development in Beijing got a substantial boost through the promotion of the municipal government.

Note: T

Note: The Ratio equals income divided by cost
Source: Beijing Statistical Yearbook 2001-2004

In terms of gross output value, the economic performance of UA is also quite outstanding, as shown in Table 7.9. For example, the annual growth rate of the gross output value for urban agriculture in processing and production is high at 26 percent during 1998-2002 (Beijing Agricultural Yearbook 2003). It can be foreseen that agricultural processing will become even a more important UA sector in peri-urban Beijing since the market potential in Beijing is huge. For the same reason, sightseeing and recreational agriculture will also have a promising future in peri-urban Beijing.

Source: Situation of agricultural processing in Beijing, 2003 (Jiuran, Zhao), Practices and explorations on high tech agricultural gardens in Beijing (Beijing Municipal Rural Commission, Beijing Fiscal Bureau & Beijing Rural Economic Research Center)

Farmer or Household Level

Urban agriculture definitely has a high economic impact on individual households, too, including that of local and migrant farmers. Farm workers in UA enterprises and urban farmers cultivating on rented plots (migrants) saw their incomes rise quickly in recent years.

According to research (Table 7.10), there were about 272,000 farm households who were involved in agro-processing activities in peri-urban Beijing in 2002 and received an income of RMB9,600 Yuan (equivalent to US$1,200) per capita, which was much higher than the average income of farmers in Beijing. In sightseeing and recreational agriculture, there were 24,000 farmer households involved, of which 20 percent were getting better-off.

Li Jinshan. 2002.

There were 2,030 agricultural associations in peri-urban Beijing in 2002, with 342,000 households as members (from 500 villages). About 80 percent of milk, 46 percent of vegetable, 35 percent of melons, and 30 percent of aquatic products in peri-urban Beijing were distributed through these associations

For the floating population of farmers, the economic impact of UA is even greater. According to a case study done by the China Regional Focal Point of the RUAF programme in 2005 (Liu, Cai & Yang), the net income of migrant farmers in peri-urban Beijing could be as high as RMB 8,000-9,000 Yuan (equivalent to more than US$ 1,000), which is more than five times the net income in their home villages. It was estimated that there were more than 100,000 migrant farmers in peri-urban Beijing in 2003, while this number is continuing to grow as the development of various types of UA activities in the city is accelerating.

Notes

¹ The basic theory on the relationship between transaction cost reduction and institutional arrangements was established by Williamson (1985). For applications in the horticultural sector, see Jaffee (1995), Lyon (2000), Moustier (1996).

² Multifunctionality is usually defined as the multiple roles or objectives that society assigns to agriculture, including economic, social and environmental roles. This "normative" definition has to be combined with a more constructivist approach which considers the synergy between the functions (Vollet, 2002; Véron, 2004).

References

Beijing Statistical Yearbooks 1996, 2001, 2002, 2003, 2004

Beijing Fifty Years Statistics (1949-1999)

Beijing Master Planning Revision (2004-2020), (unpublished)

Beijing Fiscal Bureau & Beijing Rural Economic Research Center, 2003, Practice and Explorations on Hi-Tech Agricultural Parks in Beijing, China Agriculture Press

Jiuran, Zhao. 2003. Situation of agricultural processing in Beijing in 2003, Beijing Agricultural Yearbook 2004.

LI Jinshan.2002. Investigation Report on Beijing Agricultural Industrial Adjustment and Management. Beijing Agricultural Yearbook 2002.

Shenghe Liu, Jianming Cai and Zhenshan Yang, 2003, Migrants' Access to Land in Periurban Beijing, Urban Agriculture, No. 11. pp. 6-8.

PROVE – Small Agricultural Production Verticalisation Programme

João Luiz Homem de Carvalho

PROVE – Small Agricultural Production Verticalisation¹ Programme - is a programme designed to promote small-scale agricultural production, processing and trade. It involves many urban and periurban agricultural systems, including vegetable gardening, fruit growing and livestock keeping. Intervention is at the individual and/or collective level, especially aimed at lower income groups.

Dissemination activities began with a party to celebrate the

PROVE started in 1995. In the five years prior to 1995, over 400,000 small farms were closed down in Brazil, forcing about 2 million people to leave the rural areas. This rural exodus played a major role in increasing the unemployment rate as the cities could not provide to jobs to so many people. Simultaneously, this increasing urbanisation has led to an increase in the demand for processed products. PROVE was designed to tackle both problems.

In the period of 1995-1998, under PROVE, about 500 small agro-industrial facilities were built in Brazil. During the said period, the monthly per capita family income of those involved in the programme rose from 25 to 100 dollars. On average, each project generates jobs for six people, who are usually members of the same family. The funds disbursed by the public sector (US$ 200) for each job that PROVE generates are related to expenses on wages, cars, fuel, etc. All the remaining costs are borne by the producers themselves.

The PROVE was designed to enable small farmers to overcome certain fundamental stages or hurdles in the production, processing, and trade of their products which in our opinion can segregate them. For illustrative purposes, these stages are compared to rungs in a ladder (11 rungs) that small farmers have a very hard time climbing (Carvalho 2001). Enabling them to climb these rungs is a fundamental requirement to ensure the success of the PROVE and, consequently, to ensure their social integration with sustainable development and solidarity.

1. Motivating institutions

The first step consists of an inventarisation and assessment of the stakeholders; how and for what purpose could the existing public institutions be engaged in a programme like PROVE? We ensured that the officials involved were provided with all the required information about the programme. Courses, presentations, and seminars on the need to work with socially-marginalised rural producers were used for this purpose. The political will of the government as a whole to carry out the programme was also clearly demonstrated to them. The priority was on disseminating information about the programme.

2. Providing incentives

In order to motivate a socially-marginalised audience, the advantages of the programme were described. This meant explaining the added value to small rural production schemes and collective initiatives, without closing the doors to others who wished to take part in the programme individually. The producers were encouraged to create the Association of PROVE Producers. Furthermore, the NGO APROVE (Association in Support of Small Agricultural Production Verticalisation) was established for the purpose of supporting and encouraging small farmers' initiatives.

3. Ensuring credit lines

Credit lines were provided, both by public and private finance agents, at market interest. A Guarantee Fund created by the public sector is used to guarantee loans of up to US$ 7,000 for individual projects, and US$ 25,000 for collective projects. For loans above these limits, the borrowers have to provide collateral. The grace period for repayment to each project varies according to the financial capacity of each borrower, but it typically ranges from 1 to 2 years for an individual and 4 to 6 years for collective projects. The mobile agro-industrial scheme itself is the guarantee for the bank. The idea for this scheme arose from the need to consider people who, despite having their credit applications turned down, were competent enough to generate an income and jobs. After all, like anyone else, they need to work, raise children, and lead a meaningful life.

A mobile agro-industrial facility arriving at the Luz municipality, state of Munas Gerais

4. Specific sanitary legislation and laws

It was necessary to review and reformulate the Law of the Federal District for the Inspection of Animal and Vegetal Products, as it was a hurdle for many people to engage in such activities. The state government drafted a set of rules for the construction of small agro-industrial facilities (30-40 m²) and enacted them into law. This law has served as an example for other Brazilian states and cities.

5. Building small agro-industrial facilities

Once the law was passed, projects for small agro-industrial facilities such as slaughterhouses for small and medium-sized animals and facilities for producing sweets, pre-processed vegetables, preserves, dairy products, etc. were developed.

6. Training

Training was provided to small producers for starting the production of raw materials. Visits were paid to supermarkets to provide them with theoretical and practical guidance on how to market processed or semi-processed products. Courses on the establishment of associations and cooperatives, and rural management, food hygiene and handling, specially designed for PROVE target audiences, were provided.

7. Inputs

Various inputs are necessary for manufacturing different products. In addition, packaging of the processed products determines the success of marketing. Small-scale producers do not always have enough funds to buy all these inputs. For this reason, the Small Agro-Industry Counter was created to enable small producers to buy small-sized machines and equipment.

8. Publicity and marketing

PROVE wanted the government to stimulate and fund publicity and marketing professionals on a full-time basis for designing and implementing a plan for the marketing of its products. One of the most important tasks was to create a trademark identifying the programme (PROVE means "taste it" in Portuguese) which covers all products. It also serves as a quality seal.

9. Trading the products

The small agro-industrial facilities make many products of excellent quality. Marketing of the products is the endpoint of the production process, which is also the most difficult stage. PROVE has shown that it is much easier to sell a good product with an attractive packaging and a professional label, even if it is manufactured at a small scale and by low-income people. PROVE products began to be sold in supermarkets as a result of an agreement between the states, supermarkets and producers (Pesquisa PROVE - Market Research 1998).

The producer kiosk of PROVE in a supermarket

10. Inspection and control

For consumers to be assured of the hygienic and sanitary conditions of PROVE products, they must know that they are inspected at the production site and are subject to strict quality control measures. For this purpose, chemical and microbiological analyses are carried out on the products, which are periodically inspected.

11. Follow-up

The information collected during the evaluation of PROVE (Duarte et al. 1998), showed that the programme contains the necessary elements to sustain its success - those of including small farmers in the production system and restoring their citizenship rights. The fact that small producers in the PROVE programme have developed the skills to manage their own businesses, understand the cost-benefit calculations of their activities, keep accounts and plan for the future clearly indicates the changes that have taken place in the lives of these people. The excellent ratings on transferability of the programme can mainly be attributed to the massive dissemination campaigns through the national media and to the thousands of site visits paid by people coming from different parts of Brazil and abroad to the capital, Brasilia. These people have confirmed that the programme is feasible, particularly because it can be implemented easily and at a low cost for public agencies, while also boosting the local economy.

Why PROVE did not continue in the Federal District

Why PROVE did not continue in the Federal DistrictWhy PROVE did not continue in the Federal District Despite the development and success of PROVE in the Federal District Brasilia for four years (1995-98), the creation of enabling bylaws, and the success of the programme in other regions in Brazil, the programme came to a halt in the Federal District of Brasilia.

The main reason is that the programme did not manage to create sustainable institutional structures, owned by the social actors involved (government, micro-entrepreneurs, University). It was therefore vulnerable to political changes.

With the change of government in 1999 in Brasilia District, the existing links between producers/micro-entrepreneurs and the government were broken. It appeared that the Association of PROVE producers (ASPROVE) still was too dependent on support by Government and could not survive by its self. In 2003, most agro-industries had stopped functioning or continued functioning marginally.

Of course in setting up programmes for the poor and excluded population one cannot expect them to be autonomous in just 4 years. There is a need for prolonged government support for the most vulnerable sector of society. What happened was, that the PROVE programme from the start was only supported by the then dominant ruling party, "the Workers Party", and never counted with support from opposition. A major lesson is thus, that one should try to involve and assure the support of all political parties when setting up this kind of programmes and in formulating a new enabling policy framework. This makes the programme less vulnerable to change of government.

In addition, support to poor producers should not only focus on technical production and marketing aspects. Education, capacity building and support in leadership, political lobbying, organisation and financial management is just as important to limit vulnerability and dependency on external support.

Note

¹ The strong involvement of farmers, or their relatives, in the processing and marketing of their products, can be termed as vertical integration or "verticalisation" when directly translated from Portuguese.

References

Brasil, Ida Cláudia Pessoa. 2004. Estado, agricultura familiar e desenvolvimento sustentável:construção de uma relação diferenciada. Tese de Doutorado – Universidade de Brasília. Centro de Desenvolvimento Sustentável.

Carvalho JLH de. 2001. O PROVE - Programmea de Verticalisação da Pequena Produção Familiar. Cuaderno de Trabajo 83. Programmea de Gestión Urbana - pgu@pgu.ecuanex.net.ec

Duarte LMG, Brasil ICP, Salviano OMMF, Biserra RS. 1997. Relatório de Pesquisa – Avaliação do Prove.

Brasilia: Secretaria de Agricultura do DF

Pesquisa Prove. 1998. Relatório Final. Brasilia: Instituto Euvaldo Lodi do DF.

Income Generated by Farming Systems in and around Kumasi

George Danso
Pay Drechsel
Thomas Wiafe-Antwi
Lucy Gyiele

Market proximity is a major incentive for the intensification of farming systems or change of systems to more profitable ones. A common example of such intensification is the production of perishable products, such as vegetables, in urban and periurban areas. Around Kumasi, many rain-fed maize-cassava farmers have started dry-season vegetable production along streams to generate additional income, while in the city itself, year-round open-space vegetable production is common, especially in bottomlands with access to water for irrigation. These systems are not only output intensive - with for example up to 11 lettuce harvests per year - but also manage to overcome shifting cultivation by farming on the same plot nearly continuously, despite often marginal soil quality. This is only possible through high inputs of manure, water, labour and skills (Drechsel et al. 2005). The motivation to start urban vegetable farming in Kumasi, despite the higher risk and dependency on in- and output market fluctuations, is largely economic.

Farmers in Kumasi apply poultry manure to cabbage

Kumasi is the capital town of the Ashanti Region and the second largest city in Ghana, with a population of about 1,017,000. Kumasi has a semi-humid tropical climate with an average annual rainfall of 1,488 mm. The periurban area of Kumasi extends on average to 40 km from the city centre (Adam 2001). Urban vegetable farmers in Kumasi have informal land arrangements with the authorities or private owners and do not pay rent on the land. This is done in some cases in order to keep these areas clean and to prevent encroachment by squatters. Periurban or rural farmers, on the other hand, hold short-term (eg. two year) renting or leasing agreements with the chiefs of their communities for traditional maize-cassava intercropping.

The major crops cultivated by urban vegetable farmers are lettuce (9-11 harvests/year), cabbage (2-3 harvests/year), spring onions (8-9 harvests/year), as well as "Ayoyo" (Corchorus sp.), "Alefi" (Amaranths sp.), carrots, radish and cauliflower. Urban vegetable farmers cultivate all of these crops year-round, mostly with manual irrigation, and vary crops according to their own specialisation and the market demand. In periurban Kumasi, farmers still rely on traditional and largely subsistence maize and cassava rain-fed farming. Close to streams or where shallow wells can be dug, many of them take up dry-season cultivation of, for example, okra, tomatoes, peppers and cabbage for the urban market. Besides access to water, dry season vegetable production depends on a good road network.

Surveys carried out by the Kwame Nkrumah University of Science and Technology (KNUST) with the International Water Management Institute (IWMI) as well as different British research teams have covered about 300 farm households in total. Cost-benefit analysis comparisons were made of farm finances of common rural, periurban and urban farming systems (i.e., traditional maize-cassava farming, additional dry-season vegetable growing with irrigation, and open-space year-round urban vegetable farming).

Urban and periurban farmers use water from streams, drains and dugout wells, and in a few cases pipe-borne water. In the urban areas, farmers use watering cans, whilst periurban farmers often use pumping machines or carry water from streams to their farms. Manual irrigation needs to be carried out frequently and as such makes irrigation time-consuming and expensive (13 percent of total cost – excluding family labour – and 38 percent of time spent). Only weeding was rated as more expensive by the farmers (23 percent of total cost). The cost of hiring pumps is estimated to be from US $40-70 per dry season (ca. 3 months). Most farmers who use manual labour rarely pay for it as they depend on family labour, though occasionally they hire labourers, rarely paying more than US $11 per season. In general, manual labour is more expensive per volume of water delivered (US $3-6 per m3) as compared to the use of pumps (US $0.6-5 per m3) (Cornish et al. 2001).

Farmers in Kumasi apply poultry manure to cabbage

Besides water, vegetable farmers also use significant amounts of different types of nutrient inputs as well as pesticides. In Kumasi, the use of poultry manure is very common due to its high availability and low price (US $0.1 per sack). Only a few farmers use mineral fertilisers in addition to this (mostly for cabbage). In periurban Kumasi, many more vegetable farmers use mineral fertilisers (US $14 per 50kg NPK) but combine it with poultry manure when possible.

In periurban Kumasi, women and men play similar roles in crop production while urban vegetable farming is mostly done by men. Women, however, play a major role in crop marketing in both urban and periurban areas. Traders usually purchase vegetables at the farm gate. Prices vary significantly from one season to another. Occasionally, traders provide farmers with inputs (especially seeds) in order to get them to produce the type of crops needed for sale.

In the study area, vegetable farming is done for income generation. This applies especially to those farmers growing exotic vegetables, while farmers specialized on traditional ones might also consume 20 percent of their harvest. Urban farmers occupying open space in low- or bottomlands crop all year round and attain annual income levels of US $400 to $800 (see Table 7.11); this is 2-3 times the income they could earn from rural farming. However, being successful in this type of farming requires careful observation of market demand. As urban farming is land and labour constrained, the typical farm size is around 0.1 ha. Urban farmers thus earn at least twice as much as rural farmers on only about 20 percent of the farm area.

For periurban farmers, dry season vegetable farming with irrigation can add a significant amount of cash to their income; especially as large parts of their rain-fed maize and cassava harvest are used for household consumption. Without this additional income, cash availability might actually be less than US $100 per year. However, only a minority of periurban farmers shift to year-round vegetable farming (eg. tomatoes in the Akumadan area). There are three reasons for this: the importance of maize and cassava for home consumption (mentioned by 52 percent of the farmers interviewed); the lower price of vegetables in the rainy season (40 percent); and the increased risk of pest attacks (8 percent).

Irrigated vegetable production is not only a way out of shifting cultivation but also out of poverty. Where vegetable marketing is possible, periurban and especially urban vegetable farmers make a significant step over the poverty line.

These are typical values; subsistence production has been converted to market values. PUA= peri-urban agriculture; UA= urban agriculture

References

Adam M. 2001. Definition and boundaries of the periurban interface - patterns in the patchwork. In: Drechsel P. and Kunze D (eds), Waste Composting for Urban and Periurban Agriculture - Closing the rural-urban nutrient cycle in sub-Saharan Africa (Wallingford: IWMI/FAO/CABI), pp 193-208.

Drechsel, P., M. Giordano, and T. Enters. 2005. Valuing Soil Fertility Change: Selected Methods and Case Studies. In: B. Shiferaw, H.A. Freeman and S.M. Swinton (eds.) Natural Resources Management in Agriculture: Methods for Assessing Economic and Environmental Impacts. ICRISAT-CABI Publishing, Wallingford, p. 199-221.

Cornish, GA, J.B. Aidoo, and I. Ayamba. 2001. Informal irrigation in the peri-urban zone of Kumasi, Ghana. An analysis of farmer activity and productivity. Report OD/TN 103, February 2001. DFID's Water KAR Project R7132, HR Wallingford, Wallingford, UK, 39 pp.

Danso, G., P. Drechsel, T. Wiafe-Antwi and L. Gyiele. 2002a. Income of farming systems around Kumasi, Ghana. Urban Agriculture Magazine 7: 5-6.

Resources

An Overview of Socio-Economics and Gender Aspects in Urban and Peri-Urban Agriculture: The Potential of the City of Windhoek, Namibia.
Dima, S.J. and A.A. Ogunmokun Department of Agricultural Economics and Extension, University of Namibia. 2001.
This paper provides an overview of the resources available, and the technologies used for urban and peri-urban horticulture in Namibia, followed by a survey of the recent literature on urban and peri-urban agriculture in Africa and a case study of urban and peri-urban horticulture in the city of Windhoek.

The Impact of Urban Agriculture on the Household and Local Economies
Nugent, Rachel. 2000. In: Bakker, N., M. Dubbeling, S. Guendel, U. Sabel Koschella, H. de Zeeuw (eds.). 2000. Growing Cities, Growing Food, Urban Agriculture on the Policy Agenda. DSE, Feldafing Germany. 67–98.
This chapter explores urban agriculture and its significance at household and at city level. The author discusses urbanisation and food requirements, the conditions of urban agriculture among the poor practitioners, the benefits and costs of urban farming, and the obstacles to urban farming.

Food production, urban areas and policy responses.
Ellis F., Sumberg J., 1998. Word Development, 26, pp. 213-225.
A challenging economist's vision on the (in)efficiency of urban agriculture in relation to the use of economic resources, and on the lack of legitimacy of public support (that targets urban rather than rural agriculture), written at the time attention to urban agriculture started to lead to programmes like RUAF.

For hunger-proof cities: sustainable urban food systems.
Koc, M., Mac Rae, R., Mougeot, L.A. et Welsh, J. 1999. Ottawa, CRDI, 239 p.
This book contains a review of the rationale to protect food provisioning areas close from consumers rather than importing from distant sources; includes diverse case studies, in particular in Cuba.

Développement durable de l'agriculture urbaine en Afrique francophone. Enjeux, concepts et méthodes.
Smith, O., Moustier, P., Mougeot, L., and Fall, A. 2004. CRDI/CIRAD, Montpellier, Ottawa, 173 p.
This publication (in French) includes a chapter with some insights on the conceptual frameworks at use when analysing urban agriculture, and two chapters focused on the economic and technical aspects of peri-urban food commodity chains (for vegetables and meat).

The isolated state.
Thünen, Johann Heinrich von. 1966. English edition of Der isolierte Staat. Edited by Peter Hall, Oxford, New York, Pergamon Press
This publication is referred to in several publications on urban agriculture (including this book) and cannot be missed for an economist analysing urban agriculture, for its in-depth explanation of the distribution of commodities relative to the distance to the city, plus a thorough study on land rent around cities.

The Economics of Urban Agriculture
Urban Agriculture Magazine no 7. August 2002. RUAF, Leusden, The Netherlands.

www.avrdc.org/susper/
The SUSPER regional project was initiated in January 2002 for a period of three years. On this site you will find the overview of publications. Supported by France with the Kingdom of Cambodia, Lao PDR, Vietnam RS, AVRDC, and CIRAD

www.cipotato.org/urbanharvest/home.htm
In late 1999 the CGIAR launched a system-wide initiative to direct and coordinate the collective knowledge and technologies of the Future Harvest Centers towards strengthening urban and peri-urban agriculture. The Initiative, formerly known by its acronym SIUPA, but renamed Urban Harvest has been involved supporting and implementing research and development projects in regional settings, as well as in alliance-building initiatives at global and regional level.

Sustainable management of solid waste is a major challenge being faced by municipal authorities across the world, both in the North and the South. In developing countries, urban waste remains a serious problem that causes contamination of soil and water bodies and endangers human health and the environment. Much of the solid waste consists of organic matter that can be recycled into a profitable input (compost) for urban agriculture. Composting the large quantities of organic matter provides a win-win strategy by reducing waste flows, enhancing soil properties, recycling valuable soil nutrients and creating livelihoods, but there remain several constraints that explain why this opportunity is seldom exploited. This chapter discusses the benefits of constraints to composting and presents a framework for analysis and planning of composting interventions. The arguments and models contained in the chapter are supported with case study material from Ghana, Philippines and Kenya.

Recycling of Urban Organic Waste for Urban Agriculture

Olufunke Cofie
A. Adam-Bradford
Pay Drechsel

The Urban Waste Challenge

The accelerated growth of the global urban population implies an increasing demand for public services. Yet, urban centres in developing countries are unable to meet such demand – services such as sanitation are poor or inadequate to cope with the increasing rates of urbanisation and the associated higher standards of living. According to the UN 2002 Human Development Report, 2.4 billion people in the developing world lack access to basic sanitation. In Africa, Asia and Latin America, the sustainable management of waste is a major challenge for municipal authorities. Waste is a product or material that does not have a value anymore for the first user and is therefore thrown away; however, it could have value for another person in a different circumstance or even in a different culture (van de Klundert and Anschutz, 2001). Municipal authorities have insufficient financial, technical, and institutional capacities to collect, transport, and safely treat and dispose of municipal wastes, consequently waste management remains one of the major urban problems (Drechsel and Kunze, 2001). In Ghana for example, 58 percent of the solid waste (SW) generated is dumped by households in designated dumping sites, 25 percent is dumped elsewhere in non-designated sites, and only 5 percent is actually collected. The quantity uncollected varies from place to place and could be as high as 20 percent as in the two largest cities of Accra and Kumasi. (GSS, 2000). The situation in other African cities is hardly different. In many cities household waste collection is restricted to wealthy neighbourhoods, while in the remaining areas waste is dumped along road sides, in illegal dumps and in storm water drains (Mbuyi, 1989). The city authorities in Tanzania collect only 24 percent of the refuse (Kulaba, 1989) while in Nigeria, 35 percent of Ibadan's households, 33 percent of Kaduna's, and 44 percent of Enugu's do not have access to waste collection. (Asomani-Boateng and Haight). In Ougadougou, Burkina Faso, about 23 percent of household wastes are deposited in small drains (Ousseynou, 2000). In India, about 50 percent of the refuse generated is collected. As much as 90 percent of the Municipal Solid Waste (MSW) collected in Asian cities end up in open dumps. (Medina, 2002). The failure of city authorities to collect waste leads to unpleasant conditions and decomposing wastes constitute a serious health and environmental hazard (Ali, 2004)

Block-built triple chamber compost bin being used at Apeadu Junior Secondary School, Kumasi

Urban waste could be solid or liquid, organic or inorganic, recyclable or non-recyclable. A considerable quantity of urban waste is biodegradable and hence of immediate interest in recycling (see Box 8.1).

Very large quantities of SW are generated in urban areas; the average SW generation is 0.6 kg per person per day. Based on the composition of solid waste of cities of low- and middle income countries (from Algiers, Alexandria, Cairo, Sao Paolo, Obeng and Wright, 1987), easily bio-degradable fractions range between 44 percent and 87 percent in weight (see Figure 8.1). Similar ranges (40-85 percent) are also reported by Cointreau et al. (1985) for low-income countries. Levels of urbanisation and modernisation have a profound effect on the production and composition of municipal waste; however, some general trends such as the high content of organic matter (50-90 percent) provide an opportunity for exploitation through composting processes (Allison et al., 1998; Asomani-Boateng and Haight, 1999). The percentages of organic matter in municipal solid waste in selected African cities were recorded as 56 percent in Ibadan, 75 percent in Kampala, 85 percent in Accra, 94 percent in Kigali and 51 percent in Nairobi (Asomani-Boateng and Haight, 1999). The volume and composition may however be subject to large seasonal variations (GFA-Umwelt, 1999). A detailed report on the organic waste flow in integrated sustainable waste management has been written by Dulac (2001). In short, the waste stream is not a homogenous mass but a collection of different materials (organic material, plastics, metal, textiles etc.) that can be handled in different ways to maximise recovery. The organic waste fraction remains the largest proportion to be recovered.

Figure 8.1 Solid Waste characteristics in selected cities (Drawn using data from: Hughes, 1986; Obeng and Wright, 1987; WASTE 1997; Zurbrügg, 2003; Ali, 2004)

Urban Waste Management Strategy

Many approaches to waste management exist. Generally, solid waste is managed through landfills, incineration and recycling or reuse. However in developing countries, properly engineered landfills are not common while the cost of modern incineration is too exorbitant to bear. Hence, the most common method of waste disposal is some form of landfill, including variants such as uncontrolled dumping in undefined areas, collection and disposal on unmanaged open dumps, collection/disposal on controlled dumpsites (UNEP, 2004). It is common to find scavengers moving from door to door or sorting through communal bins to pick dry recyclable materials. However, these pickers are more interested in inorganic recyclable materials such as plastics and glass, but not in organic wastes.

Agenda 21, adopted in Rio in 1992, states that environmentally sound waste management should include safer disposal or recovery of waste and changes to a more sustainable pattern introducing integrated life cycle management concepts (UNEP, 2004). It introduced a stepwise approach to waste management in order of environmental priority. The general principle of the waste management hierarchy consists of the following steps:

• Minimising wastes;
   
• Maximising environmentally sound waste reuse and recycling;
   
• Promoting environmentally sound waste disposal and treatment;
   
• Extending waste service coverage.

After Rio most countries have generally accepted this hierarchy as a strategy towards an environmentally sound waste management system. In the last ten years the concept of Integrated Waste Management (IWM) has evolved and is slowly becoming accepted by decision makers (UNEP 2004). IWM relies on a number of approaches to manage waste, including all aspects of waste management, from generation to disposal, and all stages in between with proper consideration of technical, cultural, social, economic and environmental factors. Resource recovery is critical and is embedded in this strategy.

Recycling of Urban Organic Waste

Current urban organic waste recycling practices include the following:

• The use of fresh waste from vegetable markets, restaurants and hotels, as well as food processing industries as feed for urban livestock (Allison et al. 1998);
   
• Direct application of solid waste on and into the soil;
   
• Mining of old waste dumps for application as fertiliser on farmland (Lardinois and van de Klundert, 1993);
   
• Application of animal manure such as poultry/pig manure and cow dung;
   
• Direct application or human excreta or bio-solids to the soil (Cofie et al., 2005)
   
• Organised composting of SW or co-composting of SW with animal manure or human excreta.

Whichever method is used, a process of microbial degradation releases the useful nutrients in organic waste for soil improvement and plant growth. Composting is the process of decomposing or breaking down organic waste materials (by micro-organisms such as bacteria, protozoans, fungi, invertebrates) into a valuable resource called compost. Composting is done at different scales (large, medium, small) by various people (municipalities, NGOs, communities, individuals) and for various purposes (gardening, landscaping, farming) in the urban areas. In the 1970s, large scale centralised composting was prominent especially in the Western world. However, this has proved to be a failure (Onibokun, 1999). The collection and transportation of organic waste to centrally managed sites is expensive, time consuming and energy intensive; these processes are also dependent on fossil fuel inputs that are often heavily subsidised in order to enable maintenance of fuel inputs, therefore extending economic inefficiency at the macro-level. In situations where funding is secured from donor agencies, the conditions accompanying such funds are often disincentives to good practice. Technological know-how on financial analysis, engineering design of composting facilities and transport schedule modelling has been very limited in developing countries (Cointreau-Levine, 1997). In addition, technological transfers of composting processes and equipment from developed countries were often done in the past without considering local constraints (Hoornweg et al., 1999; Etuah-Jackson et al., 2001) and the technologies transferred were often not applicable in the receiving country. Also comprehensively planned composting stations, based on a demand-supply analysis, are not common. In fact, waste management authorities in many developing countries hardly have the "luxury" of planning for recycling; instead they focus their limited resources on the priority needs of "waste collection" and "safe disposal" which consume an immense share of the municipal budgets in low-income countries as cost recovery is low (Drechsel et al., 2004). The irony is that if well planned, the costs of waste disposal could be reduced through composting. However, what appears to be a logical win-win- situation for city authorities and farmers, is seldom a reality in the developing world (see the case study by Duran et al on Marilao, Philippines, for an example of an innovative win-win solution). This is due to several factors such as lack of affordable equipment, technical personnel, frequent mechanical breakdowns, and financial restrictions (Drechsel et al., 2004; Asomani-Boateng et al., 1996).

In the 1990s, small to medium scale decentralised composting based initiatives evolved (eg. see GFA-Umwelt, 1999). However, a transition from centralised composting to decentralised composting approaches is often compounded by the lack of inter-sectoral planning (waste/planning/agriculture) in waste management. Ecological approaches to waste management have only been adopted where predominant conventional waste management approaches are not challenged. Consequently, small-scale decentralised approaches are yet to receive extensive government support at national levels. Cuba is a marked exception to this general pattern in urban planning and management. In the very different geopolitical and social conditions of Havana, Cuba, substantial progress has been made in recycling urban organic waste, as nutrient recycling principles have been implemented in practice and have proven to be very successful (Cruz and Medina, 2003; Díaz and Harris, 2005; Viljoen and Howe, 2005). But generally on a global scale, at the lowest intervention level, backyard composting is practised by few individuals.

Waste ready for collection

By far, the better composting options are those that are decentralised and use organic waste as close to the source as possible. Decentralised on-site (for commercial organic waste) and on-plot (for domestic organic waste) are the preferred levels of intervention with each individual intervention requiring the appropriate technology at the appropriate scale In essence, the primary function is all about getting the nutrients and organic matter in waste back into the soil in the most efficient and effective manner; hence the priority order of backyard composting (household) and decentralised (community) approaches (see Figure 8.2). Centralised municipal approaches do not have a good track record and the potential scale-of-economy advantages have not materialised due to operational and marketing constraints.

Figure 8.2 Composting scales of intervention

Use of Urban Organic Waste for Urban Agriculture

The provision of sufficient food and the provision of basic sanitation services, two major challenges in (mega-)cities, are inter-linked as the urban food supply contributes significantly to the generation of urban waste (Drechsel and Kunze, 2001). In principle, therefore, recycling organic waste through composting could be a win-win situation for municipalities and farmers (for example see the Marilao, Philippines case study by Duran et al.). The interests of urban waste recycling go well with the promotion of urban agriculture since urban and peri-urban farmers are in need of organic matter as a soil conditioner. Cities and towns, on the other hand, wish to conserve disposal space and reduce the costs of landfills as well as municipal solid waste management. Also important is the need to incorporate informal waste collectors and the private sector that contribute to urban waste management into this process (see Box 8.2 and the Nairobi, Kenya case study by Njenga and Karanja).

Benefits and constraints

Zurbrugg and Drescher (2002) report that the potential benefits of organic waste recycling are particularly in reducing the environmental impact of disposal sites, in extending existing landfill capacity, in replenishing the soil humus layer and in minimising waste quantity. Other benefits adapted and summarised from Hoornweg et al. (1999) with particular reference to organic waste composting are that it:

• increases overall waste diversion from final disposal, especially since as much as 80 percent of the waste stream in low- and middle-income countries can be composted;
   
• enhances recycling and incineration operations by removing organic matter from the waste stream;
   
• produces a valuable soil amendment - integral to sustainable agriculture;
   
• promotes environmentally-sound practices, such as the reduction of methane generation at landfills;
   
• enhances the effectiveness of fertilizer application;
   
• can reduce waste transportation requirements;
   
• is flexible for implementation at different levels, from household efforts to large-scale centralised facilities;
   
• can be started with very little capital and operating costs;
   
• the climate of many developing countries is optimum for composting;
   
• addresses significant health impacts resulting from organic waste such as reducing Dengue Fever;
   
• provides an excellent opportunity to improve a city's overall waste collection programme;
   
• accommodates seasonal waste fluctuations such as leaf litter and crop residues;
   
• can integrate existing informal sectors involved in the collection, separation and recycling of wastes.

Although composting seems an attractive option in many respects, it is also constrained (Hoornweg et al., 1999) by the following factors:

• Inadequate attention to the biological process requirements;
   
• Over-emphasis placed on mechanised processes rather than labour-intensive operations;
   
• Lack of vision and marketing plans for the final product - compost;
   
• Poor feed stock which yields poor quality finished compost, for example when contaminated by heavy metals;
   
• Poor accounting practices which neglect that the economics of composting rely on externalities, such as reduced soil erosion, water contamination, climate change, and avoided disposal costs;
   
• Difficulties in securing finances since the revenue generated from the sale of compost will rarely cover processing, transportation and application costs.

An evaluation of composting projects in West Africa pointed out that apart from being too expensive, a common problem leading to project failure is poor co-ordination among institutions and stakeholders due to weak institutional linkages and the lack of an enabling institutional framework, including clear legislation and policies. Experiences from six composting stations of different scales of production in five countries in West-Africa (see the overview in table 8.1 in the Annex) showed that compost stations in the sub-region suffer from a number of omissions (Drechsel et al., 2005). Lack of thorough market analysis including consideration of alternative soil inputs; transport costs; user's demand as well as willingness and ability to pay for compost prior to station set-up; lack of supportive legal frameworks and institutional arrangement to implement composting initiatives are some of these. In many cases, important stakeholders (land owners, waste collectors etc) were often not involved in planning which then constrained successful implementation. Apart from these, most composting projects are not financially viable, especially when outside funding available for the initial set up is exhausted. These points confirm the need for a comprehensive feasibility study before setting up any composting project.

Framework for Analysis and Planning of Composting

Planning is necessary to ensure a well functioning composting system. Analyses of the various segments - from waste generation, recycling to re-use - is necessary. The nutrient recycling loop concept is very helpful in this process (see Figure 8.3). The recycling loop is represented in this figure by various segments: urban consumption and waste generation, waste processing, compost demand for agriculture, along with an economic feedback mechanism and finally the legal, institutional and communal settings throughout the loop. (Drechsel et al., 2002)

The first segment of the loop, urban consumption and waste generation, addresses the supply dimensions of urban waste. It raises questions regarding organic waste production, location, ownership, quality, quantity, time, availability, value, health & safety constraints, etc. This is followed by the second segment waste processing, where questions are raised on (possibility of) organic waste transportation, appropriate processing methods (i.e. composting), production capacity, operation costs, sustainability, subsidies etc). The third segment deals with compost demand and address questions on users' demand, application, experiences, ability and willingness to pay, cultural constraints, etc. In addition to these three segments, there is an economic analysis linking the demand and composting segments that addresses economic viability, marketability and distribution. The final element looks at the legal, institutional and communal setting, in which the issues of planning, regulations, by-laws, policy constraints or support, land availability, local stakeholder participation, monitoring & evaluation, inter/intra-sectoral corporations, etc. are addressed, throughout the cycle of analysis.

Community involvement in waste collection

This nutrient recycling loop is used to scope and assess all the processes involved in recycling organic waste into a valuable resource at municipal (centralised), community (decentralised) and/or household (backyard) levels for use in urban agriculture. The model provides a diagrammatic illustration of the systematic processes that are involved in selecting an appropriate organic waste recycling technology at the appropriate scale of intervention. For an urban farmer this process may take the form of a rapid appraisal or scribbles on the back of an envelope, whereas for a community-based organisation or a municipal authority it will form a logical guide to a more detailed and rigorous assessment study.

The recycling loop gives the required framework and potential best practice for planning composting for urban agriculture (Cofie et al., 2001, Drechsel et al., 2002, 2004, Danso et al., 2005). The questions which should be addressed at each moment in this cycle are summarised in Figure 8.3. The effectiveness and usefulness of this framework was tested in Ghana (Drechsel et al., 2004) using specific methods in the analysis of each segment of the recycling loop. It is important to note however that the analysis can have various degree of sophistication depending on the specific location, scale of the intended composting project, available funds, etc.

Figure 8.3 The Nutrient Recycling Loop (modified from Drechsel et al., 2002).

Application of the Nutrient Loop

The supply of organic waste

The key question in the waste supply context is: Where is which amount of waste of what kind of quality and when is it available for composting? This will allow identification of recycling needs in terms of design and capacity. Supply studies should focus on the various types, amounts, quality, present and potential uses, current value and availability of organic municipal waste for composting. The analysis of waste supply in West Africa showed that the availability of organic waste is not the limiting factor for compost production, although, not every form of waste is always available as there are often alternative uses (fodder, fuel etc) and seasonal variations. A comparison of waste generation and availability along a south to north gradient from Accra, Ghana to Ouagadougou in Burkina Faso showed that with decreasing biomass production, the amount of organic waste and related nutrient availability per capita decreases progressively as dryer eco-zones are encountered (Danso et al., 2005)

A result of waste surveys in Ouagadougou (Eaton, 2003) indicated that 80,000 tons of organic waste is produced each year in the form of solid household waste with a nitrogen content of 26 tons. It was estimated that about 25,000 tons of organic material per year could be composted and sold to farmers for application on a relatively modest estimate of 200 ha of intensive urban horticulture plots. This would correspond to an estimated 8 tons of nitrogen. This leaves approximately 55,000 tons of organic material per year that could be spread over an area of 8,500 hectares of peri-urban staple crop fields, a flow of approximately 18 tons of nitrogen. In other words, the supply of organic material is much more than can be realistically absorbed in agriculture, at least given current economic circumstances (Tessier, A. 2004).

The demand for waste-derived compost

The demand assessment includes the characterisation of all potential clients under consideration of their willingness (and ability) to pay (WTP). It is expected that a major demand for compost in rapidly expanding cities will come from landscape designers (horticulturists, parks and gardens) and real estate developers, so this sector must not be left out in the analysis. The demand analysis should also consider socio-cultural aspects, farm economics, attitudes/perceptions of users of waste compost and actual demand projections. Danso et al., (2005) reported for Ghana that many urban farmers have positive perceptions and are willing to use compost although not all have the necessary experience. Farmers' interest in compost was both for its plant-growth enhancing (fertility) effect and soil amelioration. Variations in WTP were recorded between farmers with and without compost experience, different farming systems, urban and peri-urban farms, as well as between different cities with different compost alternatives. The WTP expressed by farmers who already used compost was in several cases lower than among non-users. This was due to past experience with poor quality compost (in Accra) which resulted in poor crop performance and the negligible market demand for "organically" produced crops in Kumasi.

Waste collection in Lomé

The study further revealed that estate developers were willing to pay higher prices for compost than urban and peri-urban farmers. In comparison to agriculture, the real estate sector has much lower qualitative requirements as compost will mostly be used for lawns and ornamentals. Thus the real estate sector could be the "favourite" customer group with options for private-public partnerships with the municipality. The financial strength of the real estate sector could subsidise parts of the compost production for agriculture.

The process of waste composting

The process of waste composting includes the determination of the type of facility, optimal number, capacity, and location of compost stations per city. Most critical in this assessment is to include possible ways of composting and determine the number of potential compost stations and station capacity with due consideration of waste supply and compost demand. Composting is best achieved by providing optimal conditions for the micro-organisms through the best combination of air, moisture, temperature and organic materials (Agromisa, 1999). Composting processes can be aerobic (with oxygen) or anaerobic (without oxygen) and even alternate between the two during the decomposition process. Anaerobic composting is a low-temperature process that is not recommended for urban agriculture due to the strong odours and the inability to destroy harmful pathogens that may be present in urban organic waste. Conversely, aerobic composting is a high-temperature process due to the development of microbes that generate higher temperatures in the compost pile. The key factors affecting the biological decomposition processes and/or the resulting compost quality are listed in box 8.3

The choice of a technology for aerobic composting will depend on the location of the facility, the capital available and the amount and type of waste delivered to the site. The two main types of systems generally distinguished are: 1) open systems such as windrows and static piles and 2) closed "in-vessel" systems. These "in-vessel" or "reactor" systems can be static or movable closed structures where aeration and moisture is controlled by mechanical means and often requires an external energy supply. (see the Kumasi, Ghana case study by Adam-Bradford). Such systems are usually investment intensive and also more expensive to operate and maintain. "Open" systems are the ones most frequently used in developing countries. They can be classified as:

Windrow, heap or pile composting: The material is piled up in heaps or elongated heaps (called windrows).

Bin composting: Compared to windrow systems, bin systems are contained by a constructed structure on three or all four sides of the pile. The advantage here is a more efficient use of space. (for illustrations see the Kumasi, Ghana case study).

Trench and pit composting: Trench and pit systems are characterised by heaps which are partly or fully contained under the soil surface. Structuring the heap with bulky material or turning is usually the choice for best aeration. Control of leaching is difficult in trench or pit composting. In some cases, composting materials are completely buried in the trench which then serves as a planting bed, for example Mtshepo's home gardening in South Africa.

Compost heaps at Kumasi co-composting plant

The aerobic composting process can last from a few weeks to 3-4 months, depending on the type of composting feedstock and the method of composting.

Mtshepo's home gardening in South Africa

Locally made composting pits in Tamale, Ghana

Emerging trends include the practice of vermiculture and the use of effective micro-organisms (EM) to accelerate the composting process. Vermiculture is the use of worms to digest organic waste into rich humus, similar to compost, that can then be applied in urban agriculture. Local varieties of both surface and burrowing earthworms can be used, although the latter are particularly suited as they not only digest organic matter but also modify the soil structure. Vermiculture is particularly suited to urban agriculture because it can be applied in a variety of settings and at different scales. The practice is also used very often as part of integrated gardening in community building urban agriculture (see chapter 6). Indeed, broad-scale vermiculture is widespread in India, Indonesia and the Philippines (GFA-Umwelt, 1999), while the practice has recently been gaining ground in Cuba and Argentina (Dubbeling and Santandreu, 2003; Viljoen and Howe, 2005). In broad-scale vermiculture, the earthworms are introduced to organic waste piled in elongated rows that are covered with some form of vegetative protection to prevent water logging (Ismail, 1997).

Planning in a Changing Environment: The Case of Marilao in the Philippines

Leoncio Duran Jr.
Joseph Batac
Pay Drechsel

Marilao is a municipality with approximately 15,000 households located on the fringe of Manila in the Philippines. At the end of the nineties, Marilao's authorities faced a typical peri-urban dilemma. With only 2,625 hectares of land area, just five kilometres away from Metro Manila, Marilao's mayor could not find affordable land for a new waste disposal site. There were more than 850 business firms and housing projects that competed for the use of municipal land. The problem was not just where to bring the waste. What to do with the recycled waste and what changes in policy and urban management needed to be made were also issues to be tackled.

Breaking with Traditional Planning Habits

The answers to the challenging question, "Where do we bring our waste?" posed in 1995 by the mayor, involved complex concepts high in capital investment requirements, but no affordable or practicable ideas. The precarious situation was emphasised during a series of community planning workshops in 1997 in search of reducing waste by getting all major stakeholders involved. With the gigantic waste problems of Metro Manila in mind, Marilao's authorities decided to go a different way, and involving the community instead.

The problem, however, was that the anticipated involvement of the community had to be tested in a country where the style of municipal governance is predominantly administrative-oriented rather than participatory. Planning has been a purely technical matter guided by a corresponding manual. However, the preparation of the development plan with community involvement, required interactive consultations with different sectors of the community. Most of the planning officers found it difficult to organise such multi-sectoral consultations. The tools and methodologies required for participatory processes had to be adopted from the NGO community. It was even more challenging to apply them in an environment, which was used to a regulatory style of management. Moreover, experience has shown that a regulatory framework alone is hardly effective, even in the Philippines, which has one of the most stringent environmental laws in Southeast Asia.

Vegetables grown in pots

Thus, a new style of local governance was required. The basis for this new style was given in 1992, when municipal local government units (MLGUs) were mandated by law to be autonomous with specific powers, functions and revenue. The mandate was anchored in certain principles, among which is the pursuit of an ecological balance and participatory processes of managing development. Each of the 1,525 units in the Philippines can have their own interpretation of these two principles, given their actual conditions and the management capacity to change them. Within this favourable atmosphere for near autonomous local governance, the municipal authority of Marilao together with NGOs, started in 1996 to brainstorm on appropriate solutions, more stakeholder participation and on investment programmes to overcome the waste crisis. It was estimated that the existing landfill would be full in about 3-5 years. Another study revealed that almost 50 percent of the current content was biodegradable waste; 30 percent could be recycled and only 20 percent consisted of non-usable materials.

The leaders of the municipal local government units and of the NGOs decided to look for ways to recover the major portion of the waste. Four months later, a proposal was finalised for the municipality to establish a composting facility, while the NGO community was to address the necessary change in behaviour of the main waste generator: the households in the municipality.

This solution was in fact supported by the Integrated Solid Waste System Framework (Presidential Task Force on Solid Waste Management 1993), which addressed the separation and processing of biodegradable waste into compost. Composting had been promoted by the national government under a specific programme since 1990 (Anonymous 1990), but like the Framework, it was more wishful thinking than implementation. To improve the situation, the national government provided a model ordinance in 1996 (Anonymous 1996) to implement an integrated solid waste management system in municipalities. Thus, Marilao was probably the first municipality actively implementing this policy.

To ensure the stable supply of organic household waste, source separation was initiated at the household level in late 1997, followed by a series of campaigns in the next two years. The activities in these campaigns involved workshops, cross visits, seminars, training, video films (on community cable TV), the playing of jingles during collection, providing the collection crew with a uniform, heralding the message of waste segregation, printing of calendars and community newsletters, and periodic letters from the mayor. The costs of these activities were shared between the NGOs and the municipality.

In general, principles of marketing were utilised for all activities, starting with an analysis of the clientele to ascertain their existing knowledge, attitude and practices (KAP). The ideal profile of potential clients was formulated and its 'appeal' determined. Distribution channels as well as promotional activities were then set up. NGOs drove the process of product development for community change. The process utilised participatory planning techniques that were designed by the NGOs. The planning interfaces again involved both the NGO leaders and the municipal staff, and were placed within the Municipal Development Planning Council (MDPC). Each year, a work plan was agreed upon and translated into investment by the municipality. The agreement only took effect after a series of consultations with community stakeholders and the mapping of internal strengths and weaknesses as well as of external threats and opportunities. This was followed by the identification of strategies, consensus on the preferred strategy, translation of this consensus into activities, and the contribution of municipal investments as well as NGO counterpart activities to implement the strategy. These investments included developing models on urban agriculture and improvements on the collection system for solid waste management. From 1995 to 2000, a total of USD 10,000 was allocated for developing models on urban agriculture. The investment for the collection system reached USD 15,000.

Reaching Households

The adoption of the practice of waste segregation was initially slow but accelerated over time. The municipality offered a predictable and reliable collection of segregated waste as an incentive, and this meant a lot in Marilao. Within three weeks, the 500 households in the first area adopted the practice, seeing that the waste collection really was predictable and more frequent. After three months, an adjoining area with 400 households decided to adopt the practice. Another 2,000 households from the contiguous area followed six months later, and the municipality had to buy more collection vehicles to maintain the promised collection frequency. Today, almost all the 15,000 households of Marilao benefit from the system by providing source separation.

The Nurture Plan

This regular supply of biodegradable waste allowed the municipality to produce compost at a rate of approximately one ton per day by using a compost fungus activator to reduce the composting time from three months to one month. The set-up of the technology needs both waste from urban households and a market, which are the urban farmers of Marilao. Initially, the compost was given to urban farmers together with seeds and tools. When the municipality realised that the compost supply could not cope with the demand, and farmers also asked for application guidelines of the compost and related information, the NURTURE plan (Networking for Urban Renewal Through Urban Ecology) was established.

The NURTURE plan identified the farmers who practise solid waste segregation and have open spaces within their yards and/or in contiguous areas. Three strategies were identified based on the crops grown: (i) food security, (ii) recreation and aesthetics, and (iii) livelihood. The farmers targeted for "food security" are the urban poor who cultivate high nutritive crops that supplement micro-nutrient deficiency, especially among children. The target group for "recreation and aesthetics" is middle class households who grow ornamentals and plants with fragrant flowers; and the "livelihood" strategy addresses farmers growing potted crops/flowers mainly during the off-season.

All three groups encountered the problem of access to land. The NURTURE plan addressed this by developing compact gardens with a standard soil composition. At first, the plan targeted guidelines for compost application, but it had to struggle with large inner-urban variations in soil quality, and some urban areas even had no soil at all but only concrete. Yet they faced a demand from farmers using pots and other containers to grow vegetables or flowers. To address this situation, the municipality carried out a series of practical experiments in 1999, which resulted in a standard substrate with compost as the predominant material for pot cultures and raised beds with rain shelters.

The farmers were organised under the umbrella of the Marilao Federation of Service Organisation (MAFESO). The MAFESO is a network of 75 community-based housing associations, church/religious groups, sectoral groups like women and transport workers, and civic clubs. In each of these organisations, there are many members who have been actively involved in the activities of solid waste recycling and urban agriculture. These members periodically plan and discuss their activities within a working committee under the MAFESO and the Municipal Development Planning Council (MDPC). The members are critical in technology applications and testing, land access arrangements and implementing the investment plan as approved in the MDPC.

The Message Spread

After a meeting with Mayor Duran of Marilao, the chairman of the Government of Metro Manila instructed his senior staff to study the Marilao model via one-day cross visits. Several more local government representatives went to Marilao on cross visits to learn about the project. In addition, national government as well as donor agencies published articles on the project, and in April 2000, the wife of President Estrada visited Marilao to learn about urban agriculture. Officials from the largest NGO in Metro Manila working on solid waste management and recycling accompanied her.

All of these interested groups and institutions had one common question – how did the programme start? The Marilao experience showed that the way to success is a stony one, which challenges old structures and planning habits. The required shift in mindset of officials and style of governance to manage development with community change can only happen when there is a strong political will. This is necessary to motivate the NGOs as well as the communities. Once there is political will, the technical aspects can be modified with a greater degree of tolerance for correction in the context of improvement. The Marilao experience has also shown that municipal planning can serve as a focus of development, as long as more participatory style of management is followed. This commitment then easily translates into investment for community mobilisation and logistics for both short and long term.

References

Anonymous. 1990. National Composting Program. Manila: Department of Science and Technology.

Anonymous. 1996. Memorandum Circular 96-119. Manila: Department of the Interior and Local Government.

Presidential Task Force on Solid Waste Management. 1993. Integrated Solid Waste System Framework. Manila: Office of the President.

Container Composting in Peri-urban Kumasi, Ghana

A. Adam-Bradford

This case study reports on the experimental implementation of container composting methods in Ghana's second largest city, Kumasi ¹. Container composting can be simply defined as the use of a receptacle or structure in which organic waste matter is composted. Using a container for composting bestows several advantages that make the practice particularly suitable for urban and peri-urban agriculture (UPA), where close proximity to human settlements becomes a consideration. Composting domestic organic waste in an urban environment may create breeding sites for disease vectors (eg. flies, mosquitoes, cockroaches, rats), attract snakes that feed on the vermin and give rise to unpleasant odours. Using composting containers can not only mitigate many of these problems, but also protect the compost pile from being adulterated with contaminated wastes, and furthermore, when good handling skills are applied, allow for extremely efficient decomposition rates. Composting then remains safe, hygienic and acceptable to local residents and, more importantly, conforms to local environmental sanitation by-laws.

Easy to operate 'Suame' compost tumbler

Table 8.2 Advantages and disadvantages of container composting

Decomposition Process

Compost containers can be used to easily obtain the optimal decomposition conditions for organic waste by regulating the air, humidity and temperature during the composting process and thus create the ideal environment for micro-organism development (bacteria, protozoans, fungi, invertebrates). Good handling of the compost pile accelerates the decomposition rate while also minimising the nutrient loss. Good practices include cutting up and shredding the organic waste, turning the pile to increase aeration, sprinkling water on the pile if it becomes too dry (dusty with ants), and keeping the container closed during heavy rains to prevent (the pile from) water logging.

Maintaining the optimal C/N ratio of 25-30/1 may require careful monitoring and appropriate handling, as nitrogen levels are often quite high when composting domestic organic waste in containers due to the concentration of nitrogen-rich matter and limited aeration. Under such conditions the compost becomes putrid, acidic and compacts, and its quality deteriorates.

This then leads to high odour emissions and the prevalence of anaerobic conditions. Turning the pile and adding dry porous materials (carbon rich), such as leaves, sawdust, or straw, can easily rectify this problem. It should be noted that if anaerobic conditions prevail thermophilic microbes may not develop, and consequently, thermophilic temperatures may not be achieved. However, in container composting this is not so crucial as only domestic organic waste is used, rather than waste from unknown sources that may contain unwanted (i.e. human) pathogens and/or agricultural residues that may contain crop diseases and/or weed seeds.

Block-built double chamber compost bin in Esereso, Kumasi

Container Design and Use

Containers can be purpose built (eg. from bricks, blocks, plastic barrels, wicker baskets) or constructed from recycled materials (eg. oil drums, plastic barrels, building materials). The space required for a composting site is approximately 1.5-2m2 per household (in peri-urban Kumasi an average traditional household consists of 10 adults and 8 children). This allocated area allows enough space to place two containers side by side, or to build two chambers if using bricks or blocks (height 1m); sufficient working space should be maintained around the front of the containers. The chambers are filled sequentially, so that when the second chamber is full the compost in the first chamber can be emptied and the mature compost stored until ready for use. In designing containers, consideration has to be made for aeration vents, drainage, ground soil contact and overhead protection.

In Kumasi, the main container-composting method demonstrated was block-built compost bins chosen mainly because of the wide availability of building blocks. Cement was used in the construction of the double-chamber bins although gaps were left between the blocks in the bottom to facilitate aeration (left without mortar for temporary use), and then each chamber was covered with a wooden lid. In some locations and in six schools larger versions consisting of three high-capacity chambers were also built and demonstrated. But regardless of the type of container selected, some fundamental design principles need to be considered including:

• Pile compost directly on ground soil thus ensuring drainage and allowing contact with soil micro-organisms (in sealed containers provide drainage holes and add fresh compost in each cycle to ensure micro-organisms are present).
   
• Provide means of aeration in container walls (holes in drums or gaps between blocks).
   
• Use covers to close containers at night and regulate compost pile during day.

Performance and Problems

Container composting proved to be highly effective for decomposing organic waste, particularly when good composting practices were followed, specifically where organic materials were shredded and the compost pile frequently aerated. Problems encountered included compost compaction and putrefaction, low participant motivation and loss of the actual composting site. During the earlier phases, some project participants eager to fill their containers with organic waste invited their neighbours and friends to also use them. As the containers were designed for individual household use they were rapidly filled, which resulted in compost compaction and putrefaction. Removing the top layers and increasing aeration of the remaining compost pile remedied this. In places where the larger capacity triple-chamber containers were used this problem did not occur.

Despite the immediate benefit for women and children of not having to make the routine early morning trip carrying daily domestic waste to the local refuse dump, the participants' motivation decreased overtime. This largely stemmed from the programme's failure to incorporate sufficient training and support in entrepreneurial skills related to compost demand and marketing. When such training was provided, participants became extremely motivated in compost production. The success of composting programmes is not dependent on the composting method or container, but principally on 'intensive care and know-how of the individual' (GFA-Umwelt, 1999), including marketing knowledge and alternative compost uses. Finally, two compost sites were actually lost due to the extension of adjacent houses. Hence, where possible, composting interventions need to be planned around future developments, although in peri-urban areas where urbanisation is rapid and spontaneous, this becomes a challenge.

Policy Implications

In the six peri-urban locations 20 demonstrations were implemented and after 3-months 17 additional micro-projects had been taken up. Early spontaneous uptake of the technology was encouraging, with the number of installations almost doubling within three months of project initiation. However, the main obstacle to further uptake was financial constraints as the average construction cost of a block built double-chamber container was approximately 13 Euro, and exceeded the purchasing power of most peri-urban farmers. In two sites where the larger triple-chamber containers were constructed, several households shared the construction costs, although this then required a much greater level of self-monitoring and household coordination.

Separating and composting domestic waste at the household level can lead to substantial decreases in waste stream outputs and thus contribute to a cleaner environment, particularly in peri-urban areas that are plagued by unmanaged open waste dumps. However, in this activity, there is a time lag before the compost is produced and the subsequent benefits are gained, so the intervention must be well planned and sustainable, with project participants actively engaged in all stages of the planning and implementation process. Failure to adopt such an approach may result in the implementation of inappropriate technologies (see Hamdi, 2004). Furthermore, the successful implementation of container composting programmes requires substantial educational and training inputs across a range of topics including establishing compost sites, constructing compost containers, appropriate compost handling, compost use and compost marketing. In Kumasi, successful implementation was enhanced through the provision of demonstrations and information leaflets and the running of composting workshops. The latter became even more effective in time when the local project participants became proficient in demonstrating composting principles. Finally regular monitoring of the composting process is also required to enable problems to be addressed as and when they arise.

Conclusions

Container composting has the potential for creating a classical win-win situation by increasing urban and peri-urban agricultural production through appropriate soil fertility management, protecting the environment through the recycling of organic waste, and income and livelihood generation, which enhance urban and peri-urban food security (Drechsel and Kunze, 2001; Leitzinger, 2001). In the context of decentralised composting of urban waste at the household level, there exist a variety of interventions that meet low-cost requirements and that are appropriate in peri-urban areas. In Kumasi, interest in the introduced low-cost technologies has been high within the selected communities. Although several households have spontaneously adopted the techniques, supplying their own materials to construct compost containers, if such programmes are to be implemented on a wider and systematic scale, then financial assistance (or purpose-built compost containers) will be required.

Note

¹ Research was funded by the UK Economic and Social Research Council (Ph.D), while the micro-projects were funded by the International Water Management Institute (IWMI), Ghana Office.

References

Adam, M (2001) Definition and Boundaries of the Peri-urban Interface: Patterns in the Patchwork, in Drechsel, P and Kunze, D (eds.) Waste Composting for Urban and Peri-urban Agriculture: Closing the Rural-Urban Nutrient Cycle in Sub-Saharan Africa. IWMI, FAO, CABI Publishing, Wallingford, pp. 193-208.

Adam-Bradford, A. McGregor, D. and Simon, D. (2006) 'Community-based waste management strategies: peri-urban interface, Kumasi, Ghana'. In McGregor, D. Simon, D. and Thompson, D. (eds.) Peri-Urban Interface: Approaches to Sustainable Natural and Human Resource Use. Earthscan, London, pp. 231-245.

Bradford, A. McGregor, D. and Simon, D. (2003) Container Composting in Peri-Urban Kumasi, Ghana. Urban Agriculture Magazine, 10: 30-31.

Drechsel, P. and Kunze, D. (eds) (2001) Waste Composting for Urban and Peri-urban Agriculture: Closing the Rural-Urban Nutrient Cycle in Sub-Saharan Africa, International Water Management Institute, Food and Agriculture Organisation and CABI Publishing, Wallingford, UK.

Hamdi, N. (2004) Small Change: About the art of practice and the limits of planning in cities. Earthscan, London.

GFA-Umwelt (1999) Utilisation of Organic Waste in (Peri-) Urban Centres, GFA Infrastruktur und Umweltschutz GmbH, Bonn (GFA Umwelt), Deutsche Gesellschaft für Technische Zusammenarbeit GmbH (GTZ), Eschborn and Ingenieurgemeinschaft Witzenhausen Fricke & Turk GmbH (IGW), Witzenhausen, Germany.

Leitzinger, C (2001) The potential of co-composting in Kumasi - quantification of the urban and peri-urban nutrient balance, in Drechsel, P and Kunze, D (eds.) Waste Composting for Urban and Peri-urban Agriculture: Closing the Rural-Urban Nutrient Cycle in Sub-Saharan Africa. IWMI, FAO and CABI Publishing, Wallingford, pp150-162.

Community-Based Compost Production for Urban Agriculture in Nairobi

Mary Njenga
Nancy Karanja

Population growth in Kenya is given as 5 percent in the past five years, while it is estimated that 20-40 percent of its inhabitants live in absolute poverty (MoPND, 2003). The poor in Nairobi seek food security and income through crop and animal keeping on small and insecure plots. Estimates by Foeken and Mwangi (2000) indicated that about 150,000 people or 30 percent of the households in Nairobi practice farming and that 80-85 percent of the cultivators are women.

Nairobi's urbanites produce about 2000 tons of solid waste daily of which 60 percent is organic (JICA, 1997). Of the total waste produced in Nairobi, only 40 percent is collectively disposed of at dump sites (ITDGEA, 2003). Heaps of garbage is found along roadsides and in residential estates. Despite the urban waste disposal problem, a well planned and regulated organic waste resource recovery is yet to be realised in many cities. This study illustrates that composting organic waste for reuse in urban agriculture is a way to alleviate urban poverty while contributing to solving the waste problem (with youth involvement) in Nairobi. Although the study did not primarily investigate the impact of composting schemes on poor urban dwellers, the results obtained nevertheless give interesting insights into these aspects.

Transporting household waste to a sorting site.

The survey among CBOs

Low-income communities produce compost in the urban and peri-urban area in order to generate income and secure self-employment. A survey was conducted in 2003-2004 on the management of organic waste and livestock manure for enhancing agricultural productivity in urban and peri-urban Nairobi. Interviews were held with ten community-based organisations (CBOs)/self-help groups in Nairobi and with a CBO from the neighbouring town of Ruiru, specialised in compost production from dump site mining. These CBOs were identified from secondary data (Ishani et al., 2002; ITDG-EA, 2003). Individual and group interviews were done with a set of semi-structured questionnaires and checklists. The survey covered group dynamics, compost and manure production, use and marketing of the products. The CBOs were analysed on their environmental management and potential to alleviate poverty.

Results of interviews

The eleven CBOs compost about 0.6 percent or 2,500 tons of the total organic waste produced in Nairobi daily. All of them aimed at generating income and tried to contribute to environmental management. Some of them in addition were involved in raising health awareness and rehabilitating of street children. The groups had been formed between 1978 and 2001, and their members generally belong to the poor section of the population and included both men and women. In Ruiru town, the CBO was made up of young school leavers of the lowest social level with diverse backgrounds. Four of the interviewed groups are located in informal settlements, two in middle class residential estates, three in retail and wholesale small to medium agriculture produce markets and two in waste dump sites (one in the City Council of Nairobi and the other at the Ruiru dump site). All the groups are located within a radius of 25kms from the city centre, except for the Ruiru group which is 40 km away. All the groups surveyed were officially registered as self-help groups.

Different types of organic waste such as household waste, market refuse, food waste from canteens and hotels, as well as agro-industrial waste (i.e. coffee husks) are collected and used as raw material for composting. Two of the CBOs only used a single type of raw material, i.e. either market or dump site waste, whereas the other CBOs composted a mixture of different waste materials. Six groups transported waste to the composting sites using wheelbarrows, donkeys and carts. Those who did not transport the waste to another location carried out composting at the source – the dump site or the market. The compost produced by the CBOs was of lower quality to the commonly used cattle manure.

Composting organic waste from the market

Different practices and materials used in composting resulted in a high variability in compost characteristics. Waste contamination at source was likely to be responsible for the high zinc and copper contents in the compost samples, particularly those taken from the dump sites. Two groups generated income by charging households for waste collection. Six groups had received formal training in compost making from development organisation such as UN-Habitat and Intermediate Technology Development Group (ITDG-EA), while others applied local knowledge which they had acquired in the rural areas. However, most of the formally-trained groups were reluctant to apply the acquired skills because they found the new/improved composting techniques labour-intensive and time consuming. Lack of space was the main challenge faced by the CBOs since composting was done either on rented or leased public land, or illegally on open spaces adjoining markets.

The study was undertaken by several different institutions that were working in partnership. The market survey identified plant nursery operators, residents of the high income estates for their ornamental gardens, and landscapers or estate developers as the main compost buyers, including a small number of small-scale and large-scale horticultural farmers from the city environs. The urban and peri-urban farmers who purchased and/or used compost were mainly those who were also members of the composting CBOs. Compost was transported by hired vehicles for distances of up to 50 km. For shorter distances, bicycles, wheelbarrows or carts were used. About 253 tons or 30 percent of the compost produced was sold at USD 67 – 133 per ton (compared to USD 14 – 24 per ton of cattle manure) which was thought to be too high considering the quality and the fact that most of the farmers still prefer chemical fertilisers.

The study revealed that compost production as a business venture is a challenge for the producer due to limited production knowledge leading to poor quality of compost. The demand for compost was very low due to lack of information on the origin of the compost and hence the fear of potential risks associated with urban waste such as heavy metal and pathogen contamination. It appeared that farmers and policy makers were largely unaware of the soil fertility and environmental management benefits of compost making.

Discussion of findings

High compost prices seem to be a major drawback to the success of this activity in uplifting the livelihoods of the youth and the poor in Nairobi in general. The high prices were not attractive to the poor urban farmers with limited resources coupled with insecure land tenure. It is not surprising that only 30 percent of the compost produced was sold, and that clients for compost were primarily business enterprises and large horticultural farms in the rural areas. These enterprises have a much better bargaining position as they can purchase large quantities of compost whereas the poor urban farmers with little land are forced to pay high prices. Farmers are interested in using organic fertilisers if the quality and price of the products are comparable to other sources of plant nutrients which include inorganic fertilisers and animal manure, and untreated waste water which is used on 36 percent of irrigated land in Nairobi (Hide and Kimani,2000). Compost production and urban agriculture are not necessarily linked to each other but efforts through the office of the Nairobi Provincial Agriculture will be rekindled so as to enhance nutrient recovery from the large mountains of organic waste especially around the wholesale markets. In Nairobi, the only urban farmers who used compost were those who had actively participated in the CBOs or who were given compost free. Therefore, besides information on product quality and price, awareness should also be raised among compost producers and users (for instance through media) how to obtain access to the compost.

Storage and marketing of compost by City Park Environmental Group in Nairobi

Conclusion

Organic waste recovery for compost making offers numerous advantages, particularly to the urban poor, as it helps to improve food security through urban cultivation and to generate income through composting. The municipal councils of Nairobi and other towns in Kenya are unable to cope with the heaps of garbage that are found all over the place. Recycling of the organic material through compost making would not only generate highly needed soil amendment fertiliser and improved community incomes, but would also result in a cleaner and healthier environment.

Acknowledgements

The authors wish to acknowledge the great input into this work made by Diana Lee-Smith from Urban Harvest-CIP, Dannie Romney from International Livestock Institute, Kuria Gathuru from Kenya Green Towns Partnership Association, Stephen Kimani from Kenya Agricultural Research Institute, Will Forst and Sammy Carsan from World Agroforestry Centre. The support made by Dionys Forster and Christian Zurbrügg Dept. of Water and Sanitation in Developing Countries (SANDEC), Swiss Federal Institute for Environmental Science and Technology (EAWAG) towards editing this case study is highly appreciated.

References

Foeken, D. and Mwangi, A. M. (2000) ' Increasing Food Security Through Urban Farming in Nairobi'. In Bakker, N., Dubbeling, M., Gundel S. Koschella-Sabel, U. and De Zeeuw H. (2000) (eds) Growing Cities, Growing Food. Urban Agriculture on The Policy Agenda. DSE pp 303

ITDG-EA, 2003, 'Nairobi solid waste management network' [Online], Available by WasteNet http://www.wastenet.or.ke/(posted 09.05.04; verified 11.02.04)

JICA (1997) Master Plan Study of Nairobi Maxwell, D.G., 1998, 'Does urban agriculture help prevent malnutrition? Evidence from Kampala', Food Policy, Vol. 23, No. 5, pp. 411-424.

Njenga, M., Gathuru, K., Kimani, K., Frost, W., Carsan, C., Lee-Smith, D., Romney D. and Karanja, N. (2004) 'Management of Organic Waste and Livestock Manure for Enhancing Agricultural Productivity in Urban and Peri–Urban Nairobi'. Project Report.

Ministry of Planning and National Development, Kenya (2003), Economic Survey.

UN-Habitat, 2003, ' The challenge of slums: Global report on human settlements', United Nations Human Settlements Programme (UN-Habitat), pp. 310.

WB, 1997, 'The use of compost in Indonesia: Proposed compost quality standards', World Bank, Washington, D.C.

Resources

Waste Composting for Urban and Periurban Agriculture: Closing the Rural-Urban Nutrient Cycle in Sub-Saharan Africa

Drechsel, P.; Kunze, Dagmar (eds). 2001. 200 p. ISBN 0-85199-548-9. CABI, Wallingford, UK; IBSRAM Regional Office for Africa, Ghana; FAO Regional Office for Africa, Ghana

This CABI hardcover publication provides an African perspective on the potentials and constraints of urban waste recycling for soil amelioration (and integrated pest management) as well as for urban and periurban farming systems. Most of the papers here are derived from an IBSRAM - FAO International Workshop on Urban and Periurban Agriculture held in Ghana in August 1999

Reuse of Waste for Food Production in Asian Cities: Health and Economic Perspectives In: For hunger-proof cities: sustainable urban food systems / Mustafa Koc, Rod Waste Recycling MacRae, Luc JA Mougeot and Jennifer. Welsh (eds), p. 136-144. ISBN 0.88936.882.1.

This paper discusses health and economic aspects of the reuse of municipal waste in South and Southeast Asia. Recent research in Bangkok, Bandung, Bangalore, Hanoi, Ho Chi Minh City, Jakarta, and Manila is used to suggest the potential for linking organic waste reuse with urban agri-aquaculture.

A Review of Waste Recycling the use of Urban Waste in Periurban Interface Production Systems

Allison, M., Harris, P.J.C.., Hofny-Collins, A.H. and Stephens, W. 1998. HDRA, Ryton Organic Gardens, Coventry, UK. P. 34

This publication is an output of a research project funded by the Natural

Resources Systems Programme of the UK Department for International Development (DFID). It is a review of urban waste and its potential use in periurban agriculture.

Municipal solid waste management, involving micro and small enterprises: guidelines for municipal managers.

Haan, Hans Christiaan; Coad, Adrian; Lardinois, Inge 1998. 154 p. ISBN 92-9049-365-8; USD 20. Publications Department, International Training Centre of the ILO, Viale Maestri del Lavoro 10, I-10127 Turin, Italy.

The focus of this publication is on micro- and small enterprises (MSEs) which have the advantage of appropriate technologies that can provide low-cost services at places where larger scale operations are either too expensive or make use of inappropriate equipment. At the same time, a number of restricting conditions that concern the extent to which SMEs can be involved in waste management operations is given. The current trend, the authors argue, is a mixed system of small and larger enterprises working together with municipalities.

Integrated Sustainable Waste Management: A Set of Five Tools for Decision-Makers. Experiences from the Urban Waste Expertise Programme (1995-2001).

Klundert, A. van der, M. Muller, A. Scheinberg, N. Dulac, J. Anschutz and L. Hoffman. 2001.WASTE Advisers on Urban Environment and Development, Gouda, The Netherlands

This series of Tools for Decision-makers on Integrated Sustainable Waste Waste Recycling Management (ISWM) presents a unique approach to municipal waste management. Integrated Sustainable Waste Management is a concept, an analytic framework and an assessment that pays attention to aspects often neglected in conventional municipal waste management. The series is based on lessons learnt in the Urban Waste Expertise Programme, a six-year research and pilot project programme (1995-2001) on urban waste in Africa, Asia and Latin America.

Further Key Readings

UNEP, IETC (2004), Waste Management Planning, an Environmentally Sound Approach for Sustainable Urban Waste Management - An Introductory Guide for Decision-makers. International Environmental Technology Center (IETC), United Nations Environment Programme, Division of Technology, Industry and Economics.

UNEP, IETC (1996), International Source Book on Environmentally Sound Technologies for Municipal Solid Waste Management. International Environmental Technology Centre Japan. SMI (Distribution Services) Limited, Stevenage, Hertfordshire SG1 4TP, England [B].

Klundert, A van de., Anschütz, J. (2001). Integrated Sustainable Waste Management - the Concept. Tools for Decision-makers. Experiences from the Urban Waste Expertise Programme (1995-2001)

Wilson, D., Whiteman, A., Tormin, A. (2001), Strategic Planning Guide For Municipal Solid Waste Management; CD-ROM, DFID and The World Bank.

Dulac, N. (2001). The Organic Waste Flow in Integrated Sustainable Waste Management. Tools for Decision-makers. Experiences from the Urban Waste Expertise Programme (1995-2001)

Cooperband, L. (2002). The Art and Science of Composting - A resource for farmers and compost producers. University of Wisconsin-Madison, Center for Integrated Agricultural Systems

Hoornweg, D., Thomas, L., Otten, L. (1999), Composting and Its Applicability in Developing Countries, Urban Waste Management, Working Paper Series #8. The World Bank, Washington DC.

Obeng, LA and Wright, FW. (1987). "The Co-composting of Domestic Solid and Human Wastes." World Bank Technical Paper No 57, World Bank, Washington, DC, USA 1987.

Nas, P.J.M., Jaffe, R. (2004). Informal waste management - Shifting the focus from problem to potential. Environment, Development and Sustainability 6: 337–353, 2004.

Coad, A. (1998), Solid Waste Management: Directory of English-Language Publications and Organisation for Low- and Middle-Income Countries. SKAT, St. Gallen, Schweiz, Distributor IT.

Lagerkvist A. (1997). Landfill Dictionary. ISWA International

Skitt, J. (1992). 1000 Terms in Solid Waste Management. ISWA International

www.sandec.ch

SANDEC is part of the Swiss Federal Institute for Environmental Science and Technology (EAWAG), Switzerland. Its activities centre on problems of sustainable development in economically less developed countries. Its mandate is to assist in developing appropriate and sustainable water and sanitation concepts and technologies adapted to the different physical and socio-economic conditions prevailing in developing countries.

www.waste.nl/uwep.htm

WASTE works towards sustainable improvement of the urban poor's living conditions and the urban environment in general. Its multi-year, multi-country programmes and projects have a focus on bottom-up development in relation to recycling, solid waste management, ecological sanitation and knowledge sharing. WASTE, located in the Netherlands, teams up with like-minded organisations in Africa, Asia, Latin America and Eastern Europe in implementing its activities.

www.ecosan.nl

This is an important new site focusing on ecological sanitation. The site provides information on the technical, financial, environmental, health, socio-cultural, institutional, political and legal aspects important for the success of (ecological) sanitation. The site also offers practical examples of sanitation systems from around the world and provides further links to sites, publications and experts.

www.wastekeysheets.net

This site assists in making a Municipal Waste Management Plan, flexible and sustainable, by applying strategic planning and Integrated Sustainable Waste Management. The key-sheets are products of the project "Building Municipal Capacity for ISWM Planning" funded by DFID's KAR programme in which three municipalities were assisted in starting up the planning process for a municipal waste plan. The activities undertaken have been reworked into key-sheets offering hands-on support and information for planners in other municipalities.

Wastewater is a resource of increasing global importance, particularly in urban and peri-urban agriculture. Wastewater is used for crop production, which includes fodder grasses, vegetables, cereals, ornamental plants, trees and flowers, timber crops and fruit trees, as well as for aquaculture and is often the only source of irrigation available. Wastewater use for irrigation generates livelihoods for farmers, agricultural labourers, produce transporters, market brokers and produce vendors. Consumers also benefit by obtaining access to fresh and cheap produce due to low transportation costs. To prevent potential negative impacts on human health and the environment, the importance of wastewater reuse in urban and peri-urban agriculture has to be recognised and clear policy guidelines for reuse need to be established. Careful research and awareness raising needs to be stimulated. Women play a key role in this context both as producers and in food preparation. Wastewater use in urban, peri-urban agriculture is a cross-sectoral issue that requires a multi-sectoral and multi-actor approach to research and planning.

Wastewater Use for Urban and Peri-urban Agriculture

Stephanie Buechler
Gayathri Devi Mekala
Ben Keraita

Introduction

Agriculture is often associated with rural areas, even though it has been practiced in urban and peri-urban areas since ancient times in backyards, on roof tops and road sides, in vacant plots and un-constructed areas, on river and lake beds and in other such small land lots. Urban and peri-urban agriculture (UA) provides nutrition and income, improves the urban environment by using the organic solid and liquid wastes of the city, provides aesthetic value to these areas and helps to achieve optimum land utilisation. However, city planners often ignore this important economic activity and do not include it in their planning. Agricultural finance institutions do not provide loans to urban farmers due partly to the fact that most of them do not have land titles and because the activity itself is considered insignificant. In addition to these factors that can hinder the success of UA, urban and peri-urban farmers often do not have access to a safe and reliable water supply. Issues related to this essential resource for agriculture are discussed in this chapter.

Collecting water from a small pond

Increasing volumes of freshwater are being converted into domestic, hospital and industrial wastewater in rapidly growing towns and cities around the world. By 2015, the world will have one billion more people than it does now and 88 percent of this growth will be in cities, mainly in developing countries (UNDP 1998). This population growth will have a dual effect: 1) a substantial increase in the volume of urban wastewater produced, since greater volumes of surface and groundwater will be diverted to supply these burgeoning cities; and 2) an increase in urban demand for food. The increasing volume of wastewater will therefore be utilised by farmers on an even greater scale than at present. Particularly in the case of urban areas in semi-arid, drought-prone areas, the lucrative and large market for fresh produce and the urban water demand will make freshwater even more scarce. The use of wastewater for agriculture in and around cities across the world is a current and future reality that cannot be denied. In some countries, such as Mexico and China, it has been practised for centuries (Shuval et al., 1986). Since conventional treatment is very costly, most wastewater is allowed to be dumped, untreated, into water bodies or onto the land. Untreated wastewater use for urban and peri-urban agriculture is often either ignored or actively condemned by the public and by government officials.

There is a small but expanding set of literature on biophysical, social, public health, political and economic aspects of wastewater and its use for agriculture. These studies are being used to inform practitioners and policymakers of the reasons for the use of wastewater, the different types of wastewater (including raw, diluted, treated to primary/secondary/tertiary level), the likely increase in its use and possibilities for mitigating the multi-dimensional risks associated with wastewater and its use.

Freshwater Availability for Agriculture

As the world population increases, the competition for freshwater resources between domestic demands, industry, commerce, institutions such as hospitals, and agriculture is intensifying. Water demand has tripled since the 1950s (Brown, 2003). Figure 9.1 illustrates that increases in urban water supply coverage have been and will continue to be greatest in Asia followed by Africa, where absolute population figures as well as population growth are the highest (Scott et al., 2004). Imminent water shortages, however, are less likely to be visible than other natural resource disasters such as deforestation and soil erosion to both the public and policymakers. This is due to the fact that much of the water scarcity is induced by groundwater overdraft for agriculture, industry and domestic use made possible by increased electricity coverage, power subsidies for diesel and electricity, and the extension of cheap credit (Shah & Scott, 2004). A huge increase in the number of wells and over-pumping with increasingly powerful diesel and electrical pumps is leading to falling water tables. Particularly serious over-pumping is occurring in China, India, USA, Pakistan, Mexico, Iran, South Korea, Morocco, Saudi Arabia, Yemen, Syria, Tunisia, Israel and Jordan. Surface water from rivers is also tapped for freshwater and major rivers either completely dry up before reaching the sea or contain only a very small volume of water. Such over-exploited rivers include the Colorado river, the Yellow river, the Amu Darya, the Nile, the Indus and the Ganges. Currently, 70 percent of surface and groundwater is used for agriculture, however with increasing competition between agriculture, industry and domestic demand, agriculture is beginning to receive less water (Brown, 2003).

Figure 9.1 Growth in urban water supply coverage by world region

Source: Scott et al., 2004

Water reuse is not a new phenomenon; it has been a worldwide practice for centuries. Agricultural wastewater, sewage wastewater (including grey water and black water) and industrial wastewater have been used directly or after treatment and/or dilution in urban and peri-urban areas for agriculture, especially in drought years. With the dwindling supplies of fresh surface and groundwater, water reuse and recycling assumes a greater role than before to keep up with the increasing population growth and the demand for increased quality and additional quantities of food.

Wastewater Production by Growing Cities

The quantities of wastewater produced by cities are rising steadily with urban growth. As cities grow, the water supply to these cities also grows, resulting in ever-increasing quantities of wastewater produced by urban residents and industries. Municipalities, farmers, and irrigation and agriculture departments are ill-equipped, however, for the very sharp rise in urban-rural water transfers (Buechler and Scott, 2006). The sources of wastewater include sewage drains, storm drains used as sewage channels, surface water sources like rivers, lakes and natural streams polluted with wastewater from city sewage and drainage channels, ponds and tanks, shallow wells, house drainage spouts and channels, wastewater treatment plants etc. The composition of the wastewater varies according to its origin. There is storm water and other urban run-off, grey water (domestic water that is wastewater without urine and faeces) or black water (domestic wastewater with urine and faeces), industrial wastewater, wastewater generated by hospitals and other institutional/commercial establishments and combinations of all of these (each with varying concentrations of waste). The volumes of wastewater generated in Asia in the late 1990s are seen in Table 9.1. An example of urban growth far exceeding the capacity of sewage collection and treatment is Delhi, India. Only about 40 percent of the capital city of Delhi has sewerage at present, and of that less than half actually delivers sewage for treatment. Most is simply channelled through open drainage canals to the main river (the Yamuna) untreated. Despite investments in new treatment plants, the growth rate of the city is so rapid that progress in proportion to this growth has been very slow (Ganges River Partnership Project, 2002).

Domestic wastewater used for vegetable production in Accra

According to the United Nations Economic and Social Commission for Asia and the Pacific and the International Water Management Institute (IWMI), wastewater treated to primary or secondary levels is used for irrigation, in industry and cooling, whereas untreated wastewater is used mainly for agriculture. Wastewater treatment is costly, and even those cities that are currently able to procure funding to build treatment plants only treat a small percentage of the total volume of wastewater. The rest is left to flow into natural water bodies. Most of the water only receives primary treatment. The majority of developing countries treat less than 15 per cent of the wastewater they produce (Davis & McGinn, 2001). Many treatment plants in cities in the South go into disuse after a short period of time due to insufficient funds for operation and maintenance. This is the situation in cities like Vadodara, the third largest city in Gujarat state, India, where none of the three treatment plants is fully functional (Bhamoriya 2004); in Kathmandu, Nepal, where many of the valley's treatment plants are in poor condition (Rutkowski et al., n.d.) and in Cochabamba, Bolivia, where the one treatment plant that exists is overloaded and therefore not working properly, and most residential septic tanks and Imhoff tanks are not functioning (Huibers et al., 2004). The percentage of the population with full water-borne sewerage connections in sub-Saharan African is very low. Harare, Zimbabwe, is one of the cities in Sub-Saharan Africa with the highest coverage while Lagos, Nigeria, has one of the lowest. In Lagos (Nigeria), Africa's largest city, with a population of 10 million, only 5 percent of its population is connected to the sewage system and treatment of sewage is below recommended standards. Only 2 percent of the cities in sub-Saharan Africa have sewage treatment, and only 30 percent of these systems are operating satisfactorily. In Addis Ababa, with a population of 2.5 million, the sewage system serves only 35,000 people (www.unep.or.jp).

Table 9.1 Estimated volumes of wastewater (million m³/year) in Asia

Policymakers' current focus is on wastewater regulation and treatment. However, to make realistic policies, information must be gathered on where wastewater irrigation takes place, the reasons for and extents of its use, the socio-economic characteristics of the main actors deriving direct and indirect livelihood benefits from this use, the risks to livelihoods and human and animal health of this use and the different types of wastewater use. A common typology of wastewater use that addresses aspects such as direct use (i.e. 'end-of-pipe' sewage irrigation), dilution of wastewater with natural surface water before use, and the relative contributions of domestic wastewater, industrial effluent, and storm water to urban wastewater is required. Van der Hoek (2004) has developed a typology (See Figure 9.2) that categorises wastewater use into three types: direct use of untreated wastewater where wastewater is directly applied to land from a sewage system; direct use of treated wastewater where treated wastewater is channelled to a particular area for irrigation; and indirect use of wastewater where wastewater is taken from another receiving water body such as a pond, lake, canal, tank or river.

Wastewater Use in Urban and Peri-urban Agriculture and its Contribution to Livelihoods and Food Security

Urban and peri-urban farmers from different caste and class groups in developing countries in Asia and Africa derive their livelihoods by using wastewater for various activities such as horticulture, fodder production for dairy activities, agroforestry, orchard keeping, floriculture, aquaculture and cereal production. There are also many areas in which the government runs sewage farms near treatment plants which are hired out to farmers for cultivation such as those around Madurai, South India (documented by Chandran et al., 2003) and around Hyderabad, India (Buechler & Devi, field observations).

Figure 9.2 Basic types of wastewater use

Source: Wastewater Typology developed by Wim van der Hoek, IWMI (2004)

To date, assessments of the extent of wastewater irrigated areas have been carried out in Pakistan, India, Vietnam, China, Mexico and Jordan. In Pakistan an IWMI study estimated that there were 32,500 hectares irrigated directly with wastewater (Ensink et al., 2004). Strauss and Blumenthal (1990) estimated that 73,000 hectares were irrigated with wastewater in India. However, Buechler and Devi (2002) estimated that just only along the Musi river that runs through Hyderabad city in Andhra Pradesh state and the canals and tanks off this river approximately 16,000 hectares of land is irrigated with urban and industrial wastewater (2003). An estimated Rs 1 million per day at least (personal communication by IRDAS, the NGO) is generated due to wastewater irrigated urban agriculture in Hyderabad. In the down stream of Vadodara, third largest city in Gujarat, India, alone, wastewater supports annual agricultural production of Rs 266 million (US $ 5.5 million) (Bhamoriya 2004). In Ghana, it was estimated that if just 10 percent of the 280 million m³ of wastewater from urban Ghana could be (treated and) used for irrigation, the total area irrigated with wastewater alone could reach 4600 ha. At an average dry season farm size of 0.5 ha, this could provide livelihood support for about 9,200 farmers in the peri-urban areas of Ghana (Agodzo et al., 2003). In Vietnam, at least 9,000 hectares of land were found to be irrigated with wastewater mostly to grow paddy, and in and around 93 percent of the cities wastewater is used in agriculture or aquaculture (Rachid-Sally et al., 2004). Mara and Cairncross (1989) estimated that 1.3 million hectares were irrigated with wastewater in China. For Mexico, estimates of the number of hectares irrigated with wastewater vary greatly between studies. Castelán has estimated the number irrigated with domestic wastewater at 344,000 ha, but states that in 1997, 403,000 ha of restricted crops (i.e. crops that are illegal to grow with wastewater as the produce is eaten raw) were cultivated (2000:25). Scott et al., 2000) has put the number at closer to 500,000 ha.

Wastewater users, who come from a wide range of socio-economic backgrounds, have a variety of motives for using wastewater for irrigation. In semi-arid and arid areas it is often the only source of water available in sufficient quantities for irrigation; it is also available year-round unlike freshwater from rainfall which is concentrated in the often short and sporadic rainy season. It is also an inexpensive source, not only of water but also of nutrients. In fact, farmers often need few or no additional fertilisers. Crop yields are often higher with wastewater than with freshwater. For example, in Haroonabad, Pakistan, it was found that wastewater farmers earn $US 300–600 more per year than non-wastewater farmers and that the majority of wastewater farmers were landless and leased in land for agricultural production (van der Hoek et al., 2002). In Kumasi, Ghana, Danso et al (2002) found that urban market farmers can earn 2-4 times more than farmers who grow maize and cassava. Wastewater farmers in and around Kumasi earn an average of US$ 340/ha per season (Cornish and Kielen, 2004). Wastewater can easily be channelled to the fields from city drains, from a river, or from broken sewer lines or carried to the fields in watering cans. Using this water is also attractive as UA fields are often conveniently located near city markets where the produce is sold, or are near urban-based buyers who purchase the produce directly from the (peri-)urban plots. As urban populations and incomes of the urban residents increase, so too does the demand for fresh vegetables and dairy products (Brown, 2005). Often, nearly all of the perishable produce for urban consumption is grown in and around urban areas due to the lack of refrigerated transportation in cities. For example, 90 percent of the lettuce and spring onions consumed in Kumasi, Ghana, are produced in the city itself (Danso et al., 2002).

Wastewater used for vegetables without prevention

Despite the widespread use of wastewater, municipalities and water boards underestimate its value, and for policymakers it is a non-issue. The lack of information and awareness both among producers and consumers about the inherent risks of wastewater use further compounds the problem. The difficulties faced in wastewater use for aquaculture relate to the non-availability of guidelines for selection of species and stocking density (Kaul et al., 2002:3). The compatibility of the reclaimed water with its intended usage is an important consideration in developing a wastewater reuse system. Higher level uses such as for irrigating public access lands (eg. Parks) and the cultivation of vegetables requires higher levels of treatment compared to lower level usage such as pasture maintenance, floriculture and agroforestry irrigation.

Impact of Wastewater Irrigated Urban and Peri-urban Agriculture on Health

Fifty percent of all children in developing countries (10.4 million children) under the age of five die per year due to malnutrition (Rice et al., 2000, WHO, 2000). Healthy individuals make healthy communities and wastewater, if well-managed, can help alleviate malnutrition especially for children of poor households. According to the draft WHO report 2005, "Guidelines for Wastewater Use in Agriculture" wastewater use in agriculture may have important economic benefits for households and communities that can improve the health of families through better access to healthcare, education, nutritious food and improved access to both water and sanitation in the household. In Hyderabad, a wastewater reuse case study showed that vegetable producers in the urban and peri-urban areas save about 20 percent of their household expenditure which they would otherwise have spent on the purchase of vegetables. Most of the households with livestock in the urban and peri-urban areas of Hyderabad, India, use wastewater irrigated para grass as fodder and generate an income through the sale of the milk. Typically, 25 percent of the milk produced (assuming a household of 6 members owns one buffalo) is retained for household consumption and 75 percent is sold (Buechler et al., 2003c). The Hyderabad and Kumasi case studies further elaborate on these topics.

On the one hand, wastewater can contribute to improved health of poor communities through income generation and increased access to food. On the other hand it can be associated with a number of health risks since most wastewater is untreated or contaminated with industrial and other wastes.

Negative impacts on farming families and local communities

The people who face potential risks from the use of wastewater for agriculture are agricultural field workers and their families, crop-handlers, consumers and those living near irrigated fields. Wastewater can have direct and indirect health impacts. Direct contact with untreated wastewater through flood or furrow irrigation can lead to increased helminth infection (mainly Ascaris lumbricoides -roundworm, Trichuris trichiura -whipworm, Ancylostoma duodenale and Nector americanus - hookworm). Two case studies that examined the impact of untreated wastewater on health, environment and income in Pakistan indicated higher hookworm infections in farmers and farm workers who use wastewater for irrigation than those who do not (Ensink et al., 2004). The main risk for the public arises when vegetable or salad crops grown with untreated wastewater are consumed raw. This can be linked to cholera and typhoid as well as to faecal bacterial diseases, bacterial diarrhoea and dysentery among consumers of wastewater-irrigated produce. Municipal and industrial wastewater is a major source of chemical pollutants that could affect human health. Chemical contaminants that pose potential health concerns and identified in untreated wastewater are shown in Box 9.1.

Wastewater can be valuable because of the bad quality of groundwater

Strategies for Managing Health Risks

There is no single solution to the problems mentioned above. Combinations of different strategies that can reduce the health risk to humans need to be adopted. Pathogens and other inorganic contaminants in the fields do not necessarily represent a health risk if other suitable health protection measures are taken. The different health protection strategies as per the draft WHO report 2005 (currently being tested), "Guidelines for Wastewater Use in Agriculture" are:

Wastewater treatment: Most conventional domestic wastewater treatment plants focus on the removal of environmental pollutants (eg. suspended solids, BOD - Biochemical Oxygen Demand-, COD - Chemical Oxygen Demand -, etc.) but not on pathogens, as the latter is more difficult and more costly and therefore not easy to undertake in developing countries. For the quality of treated water to meet the WHO standards, secondary treated water needs to be supplemented by tertiary treatment (disinfection) or retained in a maturation pond for five more days. Some research has been done to develop decentralised and cheaper treatment solutions. One example is the pilot project, "Ecology and Development with Sustainable Sanitation" (ECODESS) of the Urban Development Institute in the district of San Juan de Lurigancho near Lima, Peru. In this arid urban area on the Peruvian coast, where freshwater availability per person per year is projected to be five times less than the global average by 2025, and only 4 percent of the sewage is currently treated, this project has set up a household and a community system to collect, treat and recycle wastewater. The treated wastewater is channelled into an underground irrigation network for use in green areas and urban agriculture (Calizaya, 2002). Another economical model in Kolkata, India, for improving the quality of wastewater used in peri-urban aquaculture is the cultivation of dense plantations of crops or trees on the sides of wastewater canals, which controls soil erosion, absorbs some amount of the pollutants and provides nutrient-rich water for aquaculture (Mukherjee, 2003).

* The toxicity of a chemical depends on its concentration, the route of exposure to the chemical and the duration of exposure to the chemical. The health effects above include both acute toxicities (high chemical concentration and short exposure duration) and chronic toxicities (relatively low chemical concentration and long exposure duration) with all routes of exposure. Some of the toxicities may not be applicable to wastewater.

Sources: Chang, Page & Asano, 1995; National Research Council, 1998; WHO, 1999; WHO, 1992; WHO, 1991; WHO, 1989; ATSDR, 2000.

Choice of irrigation techniques: Farmers use different irrigation techniques depending on convenience and knowledge. However, farmers using wastewater for irrigation need to take some precautions during irrigation. Sprinkler/spray irrigation has the highest potential to spread bacterial and viral diseases and hence a buffer zone of 50–100 meters from houses or roads should be maintained to prevent health risks to local communities. Workers in the fields and their families should wear protective clothing in case of furrow or flood irrigation to prevent direct contact with wastewater. Localised irrigation techniques like bubbler/drip/trickle offer the best health protection but are expensive to implement. Still for all, drip irrigation is being taken up by some farmers as seen in Cape Verde and India (FAO 2001; Kay 2001). Vaz da Costas Vargas et al., (1996) show that cessation of irrigation for 1-2 weeks prior to harvest, wherever possible, can be effective in reducing crop contamination.

Simple techniques can be used to prevent pollution

Crop Selection: Water of poorer quality can be used to irrigate non-edible crops such as cotton or flowers, or crops that are cooked before consumption. Plants (eg. zucchini) with rough, textured surfaces, deep crevices or hairy surfaces that grow close to the ground may harbour bacteria or contaminated soil and should be avoided. But crop restriction cannot be a stand-alone solution. In Chile, the use of crop restriction, when implemented together with a general hygiene education programme, reduced the transmission of cholera related to the consumption of raw vegetables by 90 percent (Monreal, 1993).

Human exposure control: Field workers are the most exposed to wastewater. The health risks faced by these individuals can be reduced by using appropriate irrigation techniques such as bed and furrow cultivation and protective clothing in the form of boots and gloves (van der Hoek et al 2002; Ensink et al., 2004). Field workers should also be provided with sanitation facilities and drinking water. Provision of safe water in vegetable markets to wash produce is important to prevent further contamination of wastewater irrigated agricultural products. Consumers should wash fresh produce thoroughly and cook it before use. Governments should invest in employing additional health inspectors who do periodic checks on milk and meat products in the city. Finally, awareness campaigns on these issues would be of great help in minimising the health hazards of wastewater irrigation.

Treatment with chemicals and Vaccination: Immunisation against typhoid and hepatitis A for highly exposed groups is recommended (Carr et al., 2004). This therapy for adults and children in particular at regular intervals can reduce helminth infections (Ensink et al., 2004).

Developing alternatives: Improvement of sanitation, or use of innovations in the existing sanitation systems. One such innovation is Eco-Sanitation (see Box 9.2).

Farmer Innovations to Deal with Poor Water Quality and Degraded Soils

Farmers have developed a variety of different innovations in order to adapt to deteriorating water quality and degraded soils. In order to maintain or increase yields and income and to lower their health risks, they continuously react to changes in water quality and quantity and soil productivity. Some examples of farmer innovations are the mixing of groundwater and wastewater (see Buechler and Devi, 2005; Faruqui et al., 2004; Raschid-Sally et al., 2004; Ensink et al., 2002) and alternating the use of groundwater and wastewater according to the stage of plant growth (Buechler and Devi 2005). These strategies were found to increase yields, decrease pest attacks as well as decrease worm infections among wastewater irrigators and other agricultural labourers. Another adaptation made by farmers is in switching to new crops that are more suited to wastewater irrigation, for instance replacing paddy with fodder grass as it is more tolerant to higher levels of salinity, as is the case in wastewater (Buechler and Devi, 2005).

Users' Needs and Perceptions

Farmers' perceptions on the different aspects of wastewater - quality, economic value and health issues – should be brought to the attention of policymakers and urban authorities in fostering appropriate planning initiatives. By farmers we mean members (female and male of different ages) of farming households who carry out activities related to the production of crops using wastewater for irrigation. By focusing on the perceptions of members of these farming households, the different needs of wastewater-dependent households living in different locations and belonging to different socio-economic strata will be elucidated (Buechler 2004). Other factors that vary across locations and affect users' needs are: the sources of the wastewater and percentage of industrial effluent mixed with domestic sources; the de jure and de facto land tenure system; land values, land rental rates and land taxes; infrastructure (electricity grid); and the legal framework. Gathering and analysing farming household members' perceptions can facilitate the formulation of flexible "response scenarios". These could be developed for specific locations or for similar localities to identify appropriate risk reducing strategies that are technically, economically, socio-culturally and politically compatible. Users' perceptions of wastewater use have received only scant attention in studies to date.

One strategy to bring the perceptions and voices of wastewater users to various audiences is through documentary films (see Buechler et al., 2003a). In order to integrate users' perceptions into written media, their responses to key questions regarding wastewater use for agriculture must be elicited, recorded and then transcribed. Selections from the transcriptions must be incorporated into the written text of articles and other written and visual outputs and disseminated to key actors and decision-makers who will use them to develop projects and policies as an integral part of other urban planning initiatives. Newspapers, television and radio are the most popular media in most countries and can be used to disseminate information to producers and consumers. For policy makers, fact sheets and policy briefs can be developed and distributed. School children can be given educational tours to make them aware of the environmental hazards of disposing organic and inorganic wastes in water. Women can be specifically be targeted for education on the importance of cleanliness during food preparation to prevent possible infections (i.e by washing away helminth eggs), further contamination of wastewater produce and proper cooking of food.

Gender Issues

The experiences and roles of women and men in UA are gender related (see also chapter 5). Frequently, different agricultural tasks such as weeding, irrigation, harvesting and post-harvest activities that include making bundles, threshing, washing of produce, marketing etc. are divided by gender. In wastewater-irrigated agriculture, a gender division can also be discerned in the types of crops produced by men and women. The gender division of labour is context-specific. For example, in and around Hyderabad, India, mainly women are involved in both the cultivation and sale of leafy green vegetables in the surrounding wastewater-irrigated fields (Buechler & Devi, 2002; Buechler et al., 2003a). However, in and near the city of Kumasi, Ghana, most of the vegetable production is done by men while the marketing is done mainly by women (Keraita et al., 2002). In Haroonabad, Pakistan, vegetable cultivation is mainly done by women and marketing of the produce mainly by men (van der Hoek et al 2002; Ensink, personal communication November 2004). In and around Hyderabad, it was evident that women benefited in a myriad ways from wastewater-irrigated leafy green vegetable production; they benefited from the income derived from the sale of their produce and from improved nutrition for themselves and their household members. Women and children benefited also through employment created on the vegetable fields. Vegetable vendors in urban and peri-urban markets, who are mainly women, benefited through their income from sales as well as through keeping some of the vegetables for home consumption or bartering these vegetables for other types of produce sold in the market (Buechler & Devi, 2003d). Women play an important role in animal husbandry in urban and peri-urban areas in South and South-East Asia and in Latin America. Most activities associated with dairy production, for example, are performed within the domestic compound and are therefore done mainly by women, whose public space is often restricted by patriarchal social norms

Drawing water out of a well, Tanghin, Ouagadougou

(Devi et al., 2004). Fodder for these animals is often procured from wastewater-irrigated fields. Studies on wastewater use for UA and wastewater irrigation need to include gender as a variable. For example, very few studies on health risks associated with wastewater use have examined the particular risks of women versus men, or girls versus boys. Women and girls spend more time in vegetable fields in many regions of the world than men and they perform tasks such as weeding which involves direct contact with the soil and, after irrigation, with water. Many are landless, migrant field labourers with little or no access to health care services. Women's access to and control of resources is also limited in most Asian and African countries. However, it has been seen that women have greater bargaining power when they are organised as groups. Through cooperative mechanisms, women can pool resources, information, time and energy, thereby increasing their chances of developing successful livelihood strategies in urban agriculture (Wilbers, 2004).

Very few studies have focused on livelihoods of urban and peri-urban vegetable market vendors, who are predominantly women in regions such as Latin America (an exception is Brazil), Africa and South Asia. Many of these women depend on wastewater-irrigated crops for their income and household food security (Buechler & Devi, 2003c). Yet little is still known about the ramifications of deteriorating wastewater quality on the sustainability of vegetable production and sale in and around urban areas.

Education, Information and Awareness-raising

Raising awareness among farmers, policymakers, polluters, people on the market, consumers and other stakeholders is seen by many as the immediate and most important strategy to reduce the health risks associated with wastewater farming in most low-income countries.

Education and information sharing need to be tailored to each type of group that engages in wastewater dependent activities, as the user patterns of each set of actors is very different. IWMI Hyderabad has developed a series of posters translated into several local languages for dissemination to farmers (see Figure 9.3) and a documentary film on wastewater use and users. Consumers are also a heterogeneous group, using different types of wastewater-produced items. Producers, workers and consumers need to be included in information campaigns, training and information-sharing forums, so that hygiene can be improved and associated diseases prevented. Municipal authorities often do not include urban farmers as "real irrigation farmers" and therefore do not provide any extension services to them (see the Kumasi case). Awareness raising could diminish risks related to wastewater irrigation and possibly have a wider impact in combatting hygiene-related diseases in general.

As the Hyderabad Declaration states, wastewater use for livelihood activities in urban and peri-urban areas is a reality that planners and policymakers must face. Financial resources should be made available to the relevant institutions to implement appropriate measures to protect and support these livelihoods as well as to improve the health of the environment, the users and the consumers.

Institutions

Various governmental agencies are involved in shaping the policy framework into which wastewater-related activities are incorporated. Often, there is little convergence between the laws and policies of these different institutions in relation to UA and wastewater use. Enforcement of laws such as those related to the environment is often lax (Raschid et al., 2004b). Wastewater farmers often face a hostile legal and institutional environment of fines and imprisonment (Keraita & Drechsel, 2004; Buechler & Devi, 2002). Sometimes institutions even compete for the rights to allocate and/or sell wastewater (Bhamoriya, 2004; Buechler 2001). There is a need for researchers, NGOs and urban farmers to engage with policymakers at various levels and officers from various different governmental agencies to encourage a well-integrated, supportive policy environment. Poverty reduction programmes could integrate the needs of urban and peri-urban farmers such as for land tenure security and health and agriculture-related training. There is also a need to strengthen local institutions such as farmers' associations and institutions involved in sewage collection and low-cost treatment systems, and to enact by-laws that can enhance safe urban vegetable (see the Kumasi case) and other agricultural and aquaculture-related production. Membership in local institutions related to wastewater use for agriculture may be limited to those who own land. Separate institutions may exist for people of different caste, class, religion, gender and ethnic affiliations. These divisions and affiliations in membership and organizational type

Figure 9.3 Poster on risks and benefits of wastewater use

shape the constraints and opportunities faced by wastewater users (Buechler, 2004). Linkages between organisations should be encouraged to strengthen them, as is currently being done in RUAF's Multi-stakeholder Action Planning and Policy-making process. Efforts should be made to give membership to wastewater users in local institutions who have been denied this right due to their status; or else they should be accommodated in new organisations. Laws prohibiting urban agriculture or the failure of governments to respect current land tenure rights allow temporary land use that can harm the livelihoods of wastewater farmers. Laws and by-laws that support urban and peri-urban farmers and those that make a living off of wastewater produce can and need to be enacted. A key feature of the RUAF-CFF project (2005-2008) is to bring all the relevant stakeholders to one platform to encourage linkages and symbiotic association and to develop integrated, comprehensive plans.

Conclusions

Many challenges lie ahead for wastewater users involved in UA around the world. The rapid expansion of urban development will bring opportunities in terms of increased water supply for irrigation in the form of wastewater and a greater urban demand for their products. The demand will increase mainly in certain niche products for which consumers are ready to pay a premium on the freshness of the product, for example, milk, meat, fresh vegetables and fruits. However, overall land availability may decrease with urbanisation and agricultural land will certainly shift to areas that are further away from city centres. The quality of wastewater may well deteriorate if urbanisation takes place with concurrent increases in industrial, hospital and commercial effluents. Urban authorities in water and sanitation agencies, health care agencies, agriculture ministries, urban and industry planning agencies, development and welfare agencies will need to ensure that investments are made in relevant initiatives. These include domestic, hospital, commercial and industrial wastewater source separation and treatment options; promotion of water pollution prevention management techniques and technologies; provision of incentives for industries to reuse water and to use less water to minimise water pollution; preventive and curative health care measures; farmer extension services for both female and male urban wastewater farmers and farmer-to-farmer exchanges; and social programmes designed for each category of wastewater-dependent group (male and female landless labourer, land leaser, landowning farmer etc).

There are many gaps in wastewater research which hinder attempts by policymakers and practitioners to identify solutions to common problems faced by wastewater users. One such gap is the lack of knowledge of how wastewater users adapt to changes in wastewater quality and quantity over time. Innovations and adaptive mechanisms developed by farming households can be shared with other farmers in similar circumstances; these local innovations can be further refined and adapted by social and natural scientists in relevant institutions for developing effective, context-specific risk-mitigation strategies that can be promoted by governmental and non-governmental institutions. Another gap in current research is the lack of clarity on which social groups are involved in wastewater-irrigated agriculture and why. Without this information, policies and programmes that cater to the special needs of each group cannot be developed. The main risks and benefits for groundwater users in wastewater-irrigated areas are also not well understood and needs the attention of biophysical as well as social scientists. Lower-cost treatment options need further research in order to increase the capacity of urban sanitation authorities to manage their waste in a sustainable manner.

A major obstacle in the process of minimising the risks lies in the non-recognition of wastewater reuse and urban agriculture as an urban livelihood strategy. Wastewater is not a priority issue for policy makers and there is no coordination among the different institutions – municipalities, water boards, departments of agriculture, and departments of land use planning, quality control agencies – that have a stake in wastewater use. This inhibits the design of integrated solutions. The adoption of research programmes and risk-mitigation measures or enabling policies therefore depends on whether the authorities and policymakers give due recognition to urban agriculture. This will also ensure that sound legal and regulatory frameworks related to urban agriculture are sustained and enforced.

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The Use of Polluted Water in Urban Agriculture: "Livelihood realities and challenges"

Ben Keraita
Pay Drechsel

Why is Low-quality Water used in Irrigated Agriculture?

Wastewater treatment in most high- and middle-income countries is associated with conventional treatment systems. The efficiency of these systems is indicated by the percentage of households covered by sewerage and the number of operational wastewater treatment plants. In Ghana, where domestic effluents are the main sources of wastewater, less than 5 percent of households are served by sewerage, and all of them in urban areas. In other words, the efficiency of wastewater treatment is very low.

Another common sanitary indicator is the use of public toilets and septic tanks that are emptied and treated in faecal sludge treatment plants. Currently, there are 44 treatment plants (sewage and faecal sludge) in the country but most of them are small, privately-owned and almost all are in poor operational condition. Massive quantities of untreated wastewater therefore end up in urban storm water drains and in the natural drainage system, i.e. streams and rivers. In Ghana's growing cities and downstream of them, people depending on stream water for domestic or agricultural purposes are increasingly challenged by water pollution. Farmers emphasise that (land with) water close to markets and especially in the dry season is a rare resource, but one that sustains their livelihoods (Keraita et al., 2004). In fact, many of the 12,000 farmers involved in dry season vegetable farming in peri-urban Kumasi (Cornish et al., 2001) farm near polluted rivers and streams.

In Kumasi the majority of the irrigators are men

While all of the local authorities clearly recognise the challenge of providing adequate sanitation and the environmental problems, there is little that they can do due to lack of public funds. A common goal in urban wastewater treatment is to achieve a given standard, usually adopted from developed countries. For a developing country such as Ghana, Grau (1994) and Gijzen (1997) have shown that it is, however, simply unrealistic to achieve such a standard, considering the imbalance between the economic requirement and the available municipal budget. Surveys across major cities in Ghana confirm this proposition.

Livelihood Realities

Perception studies with farmers, sellers, authorities, consumers etc., have shown a general awareness among them about the low water quality, although the fact has not received much attention from any of the said groups. The question is why?

Water quality monitoring studies show that some irrigation water sources have very high faecal coliform levels (10⁷-10⁹/100 ml). These levels are comparable to that of raw human faeces, and are attributed to the dumping of raw faecal sludge into streams. One such stream is Abuabo, in Kumasi, from which Baba gets water for his vegetable farming. During the interviews, Baba said, "My father used to farm here and I continue to do the same. This is my only livelihood source, as I can get money from my sales to buy food for my family, educate my children and for other purposes" Baba could not disclose how much he earns, but studies have shown that on small plots, urban market farmers make up to USD 400-800 annually, especially during the dry season (Danso et al., 2002). This is 2-4 times the income derived from traditional maize-cassava farming on much larger plots. Baba farms on a 0.2 ha, belonging to the government and he does not pay a rent for it. He said that many youth are also taking on this activity due to lack of jobs in the city while others do it to supplement their income. Referring to the quality of the water, Baba said, "...I know that this water is not very good. The cause is the KMA (the local authority), who fails to collect the toilet waste (meaning wastewater) and therefore people dump it into the river. When we started farming, the water was good but now it is becoming bad day after day, but I need money and the market women need vegetables. So, I have to continue, I have no any other choice..."

Many farmers echo Baba's views. They lack choices for better water or better jobs, so they continue doing what they have always been doing. A ban on the use of wastewater for irrigation was tried out but enforcement was difficult; for farmers it is a "do or die" situation. Villagers, mostly downstream of cities, are crying for their once productive rivers - sources of fish for food and water for bathing and drinking – that are now dead. And consumers have no choice but to buy what is available and in this case vegetables irrigated with highly polluted water. In fact, most of the perishable vegetables are produced in the cities, as refrigerated transport does not exist. One consumer summarised this as "Ewi enhua, enye tan" (If the eye doesn't see, then it is not bad). But this is too simple. In an urban or peri-urban context where whole suburbs have no piped water, where children play on waste dumps around their homes, where toilets are hard to come by, and where raw meat is sold off the bare ground, consumers have other concerns and face more serious challenges than vegetables irrigated with polluted stream water. In 99 percent of all households, consumers are generally aware of the risks and wash or cook whatever they put on the table. This, however, might not always be very effective as studies by IWMI have shown (Amoah, pers. communication). If a child here gets sick, and it is not due to common malaria, then it is most likely caused by playing with waste, poor sanitation or bad drinking water. These are the priority issues that the municipalities are trying to tackle, and waste management already takes 60 percent of their budgets. Perhaps, the child fell ill by eating a piece of raw lettuce, one of the many other possible reasons in an environment so greatly different from the world where "wastewater irrigation guidelines" exist.

Watering is done by hand and is hard labour

The Way Forward

The obvious challenge is the differentiation between actual and potential health risks, and the comparison of actual risks with actual benefits in a given situation. In a survey IWMI carried out in Kumasi in 2001, all health professionals interviewed enumerated a number of negative health impacts, which they attributed to wastewater use. This perception was also supported by standard literature (Shuval et al., 1986, Blumenthal et al., 2000) and led to the imposition of a by-law in Accra that bans drain water use in agriculture. Although hardly enforced, arrests of urban farmers were reported in 2002. This perception of health risks constrains the recognition of irrigated urban agriculture in the country despite its documented contribution to jobs and income and the supply of city markets with perishable crops such as vegetables (Danso et al., 2002). For example, 90 percent of the lettuce and spring onions consumed in Kumasi are produced in the city itself.

As in other low-income countries, irrigated urban and peri-urban farming is a growing enterprise in Ghana, which requires no external facilitation, but would be much more productive when recognised by the authorities., tenure security etc., for example in the frame of poverty reduction programmes. But as much as support is needed to enhance the benefits of irrigated urban agriculture, equal emphasis should be given to health risk reduction measures (Drechsel et al., 2002).

Considering the large number of stakeholders involved, dialogue and platform building will be crucial elements of any balanced approach to move wastewater irrigation forward. Such an approach has to be innovative and should address the following aspects:

Prevention: In many West African cities, municipal planning is under-resourced, not legally binding and is unable to keep track with the urban sprawl. Entire suburbs develop with no provisions for sanitation or other infrastructure such as schools, hospitals, parks etc. In the best case, storm water gutters take over sewerage functions. There are no provisions or plans for wastewater collection or treatment. Urban planning needs much stronger support to address sanitation challenges long before they arise!

Low-cost technologies: But actors involved in managing wastewater at the generation, treatment and disposal phase need to be practical and realistic. Most facilities and regulations have been designed based on experiences and standards from the developed world, where taxes and sanitation fees can easily maintain whole treatment systems. Adopting simple, possibly decentralised systems with low-cost treatment options has not received adequate attention, but appear more suitable though less prestigious.

Agricultural use oriented: Growth in urban populations has not only led to increased use of water, hence more wastewater generation, but also to increased urban food demands. If the crucial link of generation/treatment of wastewater to agricultural use is made, then the perception of wastewater as a nuisance will change to that of a valuable resource.

Alternative risk reduction strategies: Actors should work together to look for non-traditional, user-oriented strategies to reduce health risks, also in situations where perfect treatment plants are not feasible. Low-cost but well-targeted options are possible at the farm level with extra attention on post-harvest contamination at the household level. Such options will have to be linked with awareness and sensitization campaigns.

References

Blumenthal, U.J., A. Peasey, G. Ruiz-Palacios, and D.D. Mara. (2000). Guidelines for wastewater reuse in agriculture and aquaculture: recommended revisions based on new research evidence. WELL Study No. 68 part 1, June 2000. WEDC, UK.

Danso, G., P. Drechsel, T. Wiafe-Antwi and L. Gyiele (2002). Income of farming systems around Kumasi, Ghana. Urban Agriculture Magazine 7: 5-6.

Drechsel, P., U.J. Blumenthal and B. Keraita (2002). Balancing health and livelihoods: Adjusting wastewater irrigation guidelines for resource-poor countries. Urban Agriculture Magazine 8: 7-9

Gijzen, H.J. (1997). Duckweed based wastewater treatment for rational resource recovery. In: II Symposia Internacional sobre Ingenieria de Bioprocesos, Mazatlan, Mexico, 8-12 September 1997, pp39-40

Grau, P. (1994). What's next? Water Quality International, no. 4:29-32

Keraita B and P. Drechsel. (2004). Agricultural use of untreated wastewater in Ghana. In Scott C.A, N.I. Faruqui and L. Raschid-Sally, Wastewater use in Irrigated Agriculture, Confronting livelihoods and environmental realities. IWMI-IDRC, CABI publication, pages101-112.

Shuval H. I., A. Adin, B. Fattal, E. Rawitz and P. Yekutiel. (1986). Wastewater irrigation in developing countries: Health effects and technical solutions. World Bank Technical Paper No. 51. Washington, U.S.A: The World Bank.

Wastewater Treatment and Reuse for Food and Water Security

Naser I Faruqui

In the Middle Eastern and North African (MENA) countries, water is the key development issue. The average rate of the region's annual population growth is one of the highest in the world (around 2 percent) while its natural water supply is scarce. As a result, average renewable fresh water availability in the region has dropped to about 1,428 m3 per year, though many countries in the region fall well short of this¹. Moreover, the available water is of a lower quality because of increasing pollution and over-pumping.

This situation is compounded by the high urbanisation rate in MENA. It varies from 1.8 percent in Egypt to 4 percent in Palestine² and 4.6 percent in Yemen (with an overall rate for the MENA of 2.8 percent,). On average in the region, more than 50 percent of the population lives in cities, with about 91 percent in Lebanon. Within MENA, about 88 percent of all fresh water is used for agriculture. Despite low urban tariffs, the value of water is at least 10 times higher in the urban areas than it is in the agricultural areas (Gibbons, 1986). As a result, water will increasingly be taken out of agriculture and put into urban areas. This means that the region will increasingly suffer from twin and related problems of food and water insecurity.

Permaculture Garden using greywater in Tufileh, Jordan

Many countries in the region wish to increase fresh water supplies for domestic and industrial usage, and at the same time expand irrigated agriculture. How can these seemingly contradictory objectives be reconciled? The answer is water-demand management; more efficient water use within all sectors. A specific component of this strategy is to use treated domestic wastewater for industry, for certain municipal purposes such as flushing toilets and irrigating green spaces, but, above all, for urban and periurban agriculture (UPA).

There are a number of benefits in using treated wastewater. First, it preserves high quality and expensive fresh water for drinking. Second, collecting and treating wastewater protects existing sources of valuable fresh water, the environment and public health. In fact, wastewater treatment and reuse (WWTR) not only protects valuable freshwater resources, but also supplements these through aquifer recharge. If the benefits of environmental and public health protection were correctly factored into economic analyses, wastewater collection, treatment and reuse would be among the highest priorities for scarce public and development funds. Third, if managed properly, treated wastewater can sometimes be a superior source for agriculture than fresh water. Not only is it a constant source of water, the nitrogen and phosphorous in the wastewater may result in higher agricultural yields than freshwater irrigation, eliminating the need for additional fertiliser application.

The countries in the region that treat wastewater include Kuwait, Saudi Arabia, Oman, Syria, UAE and Egypt. However, only Israel, Tunisia and Jordan practise wastewater treatment and reuse as an integral component of their water management and environmental protection strategies.

About 80 percent of Israel's treated wastewater is reused in irrigation. In Tunisia, 18 percent of its treated effluent - a total flow of 250m³/d - is used to irrigate about 4,500 ha of orchards (citrus, grapes, olives, peaches, pears, apples, and pomegranate), fodder crops, cotton, cereals, golf courses and lawns. Almost all of Jordan's treated wastewater is reused - the wastewater collected and treated in the As-Samra wastewater-treatment plant is blended with fresh water from the King Talal reservoir and used for unrestricted irrigation downstream in the Jordan Valley, to produce crops including lettuce, peppers, tomatoes and olives. To a lesser extent in Tunisia, but particularly in Jordan - given that even the furthest sites within the Jordan valley are less than a 45-minute drive from Amman — the agriculture practised can be considered periurban, characterised by its closeness to urban areas, its focus on high-value fruits and vegetables, the relatively small size of plots and the intensity of production. In these countries wastewater reuse is planned at the national level, with effective coordination between relevant ministries, including agriculture, environment, water resources, health, and the water and sanitation utilities. In fact, in both, ordan and Tunisia, these functions are combined in one ministry.

Grey Water Reuse in Urban Agriculture in Jordan

With its low and rapidly decreasing per capita water availability of 148 m³/p/y, less fresh water will be available for agriculture in Jordan. One means of addressing this threat to food security is to treat and reuse domestic wastewater in UPA. An IDRC-supported project found that 16 percent of the households in Amman already practice UPA, mainly for the production of fruits, vegetables and herbs. The annual value of UA in Amman is US $4 million - already 2.5 percent of the total value of agriculture in Jordan (Government of Jordan, 2002). The problem is that only 40 percent of wastewater in Jordan is collected and treated. The necessary rehabilitation and expansion of the conventional sewerage and wastewater-treatment systems will take time and millions of dollars.

Greywater Treatment and Reuse in Tufileh, Jordan

IDRC's research partners have come up with a new approach to combat food insecurity - helping the poor to harvest water at the household level. The systems consist of minor plumbing modifications that divert water from showers, bathrooms and kitchen sinks through small-scale, natural filters in each household allowing residents to recycle water for reuse in home gardens (See photographs). Grey water reuse is much safer than combined wastewater reuse because grey water does not contain pathogens from the toilet. Also, because most "wastewater" is simply "grey water," diverting it from the public sewerage system can dramatically reduce the costs required for installing and expanding such systems. In this pilot project, grey water-treatment systems were installed in 25 homes in Ain Al Baida, Jordan, and members of the households were taught how to set up efficient gardens. Systems were also installed at the main mosque in the community, and at a girl's school. A further 300 systems are currently being installed in another peri-urban area as part of a second phase of this project.

The project has exceeded expectations. The grey water effluent meets standards for restricted irrigation, and households are using it to irrigate eggplant, herbs and olives. The impacts on poverty and water use are still being measured. However, an IDRC study on a previous untreated grey water-reuse project found that the community was able to offset food purchases and generate income by selling surplus production, and by saving or earning an average of 10 percent of its income. Initial water savings were about 15 percent. The economic impact of this project is likely to be much higher because the grey water recovered in this project has already reached 60 percent of the domestic water, nearly twice as much as the previous project in which it was only about 30 percent. Furthermore, previously overflowing septic tanks that cost at least US $60/yr per tank to pump out have not been emptied since the project began. Economic benefits certainly have been significant enough to impress the neighbours of the original beneficiaries - they are now installing the systems at their own cost, proving that households recognise that wastewater treatment can save them or make them money. The Inter-Islamic Network on Water Resources Development and Management (INWRDAM) has improved the original design developed in Palestine with innovations that make the systems safer and more efficient. The medium used in the filters is either gravel or pieces of old irrigation piping. A simple bag filter eliminates clogging associated with previous systems. INWRDAM has also developed an environmentally- friendly dishwashing liquid that prevents soil salinisation arising from grey water reuse, and has begun training workshops on grey water reuse for low-income settlements in Syria and other network countries. The Jordanian Deputy Minister of Social Welfare has visited the Jordan project and is interested in the potential of the systems to alleviate poverty. Also, the Water Authority of Jordan (WAJ), a part of the Ministry of Water, is testing the effluent quality of the systems, at its own cost.

Recommendations

Compared to other countries in the region, Israel, Tunisia and Jordan have successful treatment projects. Based on the experiences of these projects, governments in MENA need to create an enabling environment to encourage safe wastewater treatment. Treatment must form part of an integrated water-management strategy at the basin level, with multi-disciplinary linkages between different sectors such as environment, health, industry, agriculture and municipal affairs. For instance, the main producer of wastewater- municipalities - must interact with the main user - urban agriculture. Urban and rural planning must be integrated so that industries are not situated in locations where their effluent, often high in dangerous constituents such as heavy metals, will contaminate water meant for the biggest user, agriculture. Governments should further facilitate the participation of stakeholders in wastewater-treatment projects, including supporting NGOs working in institution building at the local level. Safe and sustainable decentralised projects will never be established without the willing participation of the beneficiaries. There is also a need to disseminate existing knowledge about the danger of raw wastewater reuse, safe reuse guidelines and the position of Islam on wastewater reuse. There is a perception in MENA that Islam prohibits wastewater use, but in fact as long as the wastewater is treated to extent necessary to protect public health, wastewater use is allowable (Faruqui et al., 2000). Knowledge of cost-effective treatment technologies and crop and soil protection must also be disseminated and site-specific research carried out to fill missing gaps. Most importantly, perhaps, the economic benefits of successful decentralised wastewater-treatment projects must be disseminated to periurban households and farmers, who will only then be willing to contribute to the costs of WWTR. Finally, to ensure the protection of public health and the environment, governments must regulate and monitor the quality of effluents, reuse practices, public health, crop-water quality, and soil and groundwater quality.

Notes

¹ World Development Indicators, 2005, World Bank

² The statistics of 4 percent was obtained from UNICEF country data

References

Faruqui, N, AK Biswas and MJ Bino MJ. 2001. Water Management in Islam. UNU Press and IDRC Books, Ottawa, Canada.

Gibbons, D. 1986. The Economic Value of Water. Resources for the future, Washington, DC.

The urban setting offers special advantages for food and animal production, but also presents particular challenges. Urban agriculture needs to be highly innovative in competing and adapting to new situations. Urban and peri-urban agricultural systems exhibit even higher levels of complexity than rural upland systems and call for a wider range of participatory methods. This chapter discusses participatory agricultural research and its relevancy for the urban setting. A sustainable urban livelihoods framework is discussed, which enables to better understand and define the multi-sectoral, institutional and policy aspects of urban agriculture in order to identify appropriate interventions. Specific participatory methods are discussed for urban horticulture and livestock to help urban producers adapt agriculture to urban realities.

Participatory Technology Development for Sustainable Intensification of Urban Agriculture

Gordon Prain

Introduction

The production of food, feed, fuel and construction material in and around cities has almost as long a history as human settlements themselves. The earliest cities in the Fertile Crescent, in China and in South and Central America report the presence of local food production, which was an essential component of urban food security in times of conflict and military insecurity (Southall, 2001). The urban setting offers special advantages for food and animal production, but also presents particular challenges. Cities accumulate nutrients through the concentration of human population and their organic waste products, whether in solid or liquid form. These nutrients can often be acquired free or at low cost and can be converted into edible plant parts or animal products. On the other hand, as cities develop, there is increasing demand for residential and business accommodation which competes with agricultural space. Producers must adapt to these more constrained conditions, whilst still trying to maintain productivity through intensifying production techniques.

Producers' adaptation of agriculture to urban realities also occurs within a policy environment which is much more challenging than the rural context. This is partly because of the density of the population and intense competition for natural, physical and financial resources in urban settings which municipal governments try to arbitrate. It is also because of the density of competing economic and political interests present in the city, in which the local council is only one player.

The treadle pump used around Accra for irrigation of vegetables

Another feature of cities is their dynamic nature: a constant flux of growth, decay and transformation which puts a very high value on continuous technological innovation to maintain or enhance productivity and sustainability. As part of their livelihood strategies, urban producers are already engaged in innovative adaptation to new circumstances. This chapter argues that to support them, we need to employ participatory methods, for the same reasons as they have been essential for working with complex rural agriculture systems – mixed upland systems for example - the need to combine local knowledge and innovation skills with new technical opportunities.

This is the context for participatory technology development in urban agriculture systems which will be explored in the following sections.

Agricultural Technology Development

Why has agricultural research been so little concerned with urban agriculture (CGIAR 1998). The answer is related to the sectoral separation of "urban" and "rural", a separation that has its roots in the Industrial Revolution and its subsequent transfer through colonial expansion to the developing world.

In northern Europe, the industrial revolution came to be seen as an urban revolution, associated with cities such as Manchester, Liverpool and Birmingham in the north and midlands of England. The workers who were employed in the new factories came from agricultural communities. Cities became part of what was seen as a movement away from an agrarian society towards industrialisation and the creation of wealth through capital investment. Rapid urban growth occurred around manufacturing and service industries and included dense, low-cost residential housing for the new industrial workforce – the future inner city slums – together with elite suburban settlements, occupied by the "captains of industry" and the professional classes who supported them (Fishman, 1987). Yet this division was more ideological than real. Because transport systems failed to keep pace with urban growth, food supply to cities remained a problem. In England and other European countries, municipal authorities were obliged to "allot" small plots to workers' families for food production (Burchardt, 1997). These allotment gardens have been reduced in size or have changed location, but they never left the cities in Europe.

Watering roof top vegetables

The colonial expansion of northern European economies, driven by the search for new sources of raw materials as well as for new consumer markets, exported the sectoral divide between "rural" and "urban" to the developing world, with efforts made to keep "rural" agricultural local populations out of the colonial urban centres, except for the provision of services to the colonists (Tibaijuka, 2004).

This divide has come also to characterise the investment by public sector agencies in technology generation. Agricultural technology development has been almost exclusively oriented towards rural needs, whereas research on manufacturing processes, product transformation, infrastructure and sanitation has been focused mainly on urban needs.

Early investments in research and development for rural agriculture were primarily associated with fertiliser development (an off-shoot of military research into munitions and one of the few examples where weapons really have been turned into ploughshares), pesticide development and more recently, especially in the second part of the 20th century, plant genetics and breeding (Simmonds, 1979). Plant breeding began to be applied to the developing world's main food security crops of rice, wheat and maize during the 1960s, seeking to increase the fertiliser responsiveness and harvest index of the crops (ratio of grains to other parts of the plant biomass) and therefore their food productivity.

The methodological background to this technology development process, which became known as the Green Revolution, was the notion of a central source of innovation (Biggs, 1990; Biggs and Farrington, 1991). This notion proposes that agricultural innovations are generated in centres of excellence by scientists, are then pushed out to national agricultural programmes which may conduct some local adaptive research before transferring the technology to extension services and thence to early-adopting farmers, who then abandon traditional practices. Although this "pipeline" or top-down approach succeeded in greatly increasing the production of rice, wheat and maize in the relatively simple farming systems in breadbasket regions of the developing world – the Indo-Gangetic plain, the irrigated lowland valleys and plains of Southeast Asia, the maize-producing valleys of central Mexico – it made little impact on ecologically, agronomically and socio-economically more complex upland farming systems. These systems have to adapt to difficult, risk-prone environments and this demands local farmer innovation in crop-livestock management in multiple micro-environments. A quite different, participatory approach to agricultural research is required to enhance the capacity of these systems to ensure year-long food and income security for households.

In these more complex situations it is necessary that researchers and agricultural producers first conduct situation analysis (Martin et al 2001) to analyse the existing strengths and weaknesses of local farming systems, regional agro-enterprise and marketing systems (Bernet et al., 2005) and the body of available indigenous and incorporated knowledge. Farmer-led experimentation can then evaluate alternative options for change, drawn from both local experience and national and international scientific resources. This is the essence of participatory technology development (PTD), an on-going process of innovation that blends new and tested principles and practices to changing local realities (Chambers et al., 1990; Haverkort et al., 1991; Douthwaite, 2002).

Participatory planning undertaken in Dar es Salaam

This brief review of the background to participatory agricultural research is relevant because urban and peri-urban agricultural systems exhibit even higher levels of complexity than rural upland systems and call for a wider range of participatory methods (Veenhuizen et al., 2001). As well as the need for situation analysis of the diverse mixed farming systems in a range of (urban) micro-ecologies, there are specific interactions with the urban environment that must be analysed. These concern the opportunities and risks of accessing and recycling accumulated urban nutrients (Dubbeling et al., 2005); the need to adapt and intensify production in space-constrained conditions (Veenhuizen, 2003); the risks of exposure to urban contaminants (Cole et al., 2004); the opportunities of agro-enterprises and accessing diverse nearby markets (Holmer, 2001; Peters et al., 2002); and the need to engage with a dense and often intrusive regulatory, policy and planning environment, which impinges on agriculture in multiple ways and makes demands on the types of technologies that can be used (Dubbeling, 2001).

Finally, agricultural production in urban areas is rarely the only or even the major livelihood activity of households. It is combined and sometimes integrated with part- or fulltime activities in other urban sectors, such as the construction, manufacturing and service industries¹. This creates intricate decision-making processes within households regarding the deployment of household resources in livelihood strategies. Gender and inter-generational relations and sustainability considerations are part of these processes and a more comprehensive framework is required for their analysis and for the design of interventions (Rakodi and Lloyd-Jones 2002).

In the next section the sustainable urban livelihoods framework will be introduced, to better characterise the multi-sectoral, institutional and policy aspects of urban agriculture and identify appropriate interventions. After that, several specific participatory methods to help urban producers adapt agriculture to urban realities will be reviewed.

Farming Systems and Livelihood Systems in the Urban Environment

The concept of "farming system" was developed during the 1970s to capture the multiple, integrated components and large-scale continuities in rural agriculture and to identify points of technology intervention for particular types of systems (Norman et al., 1995). It also has value to understand the situation of urban agriculture, which exhibits a similarly high degree of biological and agronomic diversity at one level but also the potential for identifying continuities, common features and broadly applicable interventions. Farming systems research seeks to understand the integration of agricultural production involving crops, animals and the use of natural resources, the deployment of household and hired labour and linkages with markets. Its weakness has been its agro-centrism - seeing everything through the agricultural lens and often the lens of the individual farmer – and also a difficulty to characterise adequately the feedback loops linking the farm and farm household with other local and regional systems, whether ecological systems such as watersheds or socio-political systems such as local political structures, food systems and different kinds of markets.

The more recent emergence of livelihood systems approaches has enriched action research and development work with agrarian societies, by adopting a broader perspective that analyses households dynamically, in terms of the deployment of their accumulated assets through livelihood strategies that are constrained both by external stresses and shocks and by the need to engage with local and national institutions, policies and processes (Farrington et al., 1999). Although developed to better analyse rural realities, this approach has proved to be very fruitful for understanding households in urban settings, including those engaged in different kinds of agricultural production (Radoki and Lloyd-Jones, 2002).

Increasingly in rural settings, and very much so in complex urban contexts, poor households depend on multiple income sources, credit, physical resources such as equipment and technology, access to natural resources, and a range of non-material assets such as local knowledge, formal education, health and social support structures to ensure their livelihood. Inadequate assets can leave households vulnerable to economic, environmental, health, and political stresses and shocks, which is referred to as the vulnerability context (Figure 10.1).

Figure 10.1 Sustainable Urban Livelihood Framework

Adapted from DfID 2001. Sustainable Livelihoods Guidance Sheet. DfID, London

Household-based Assets have been Classified into Five Types or Capitals²

Natural capital involves the quantity and quality of accessible land, water and biodiversity. The basic ingredients for both crop and livestock agriculture are water and nutrients. Nutrients for crops are delivered mostly through soils, though their delivery in water in hydroponics systems is also important in urban settings (see below). Conditions and management of soils differ widely in urban settings and across different types of urban and peri-urban agriculture, though frequent, common problems include the presence of inorganic materials – especially heavy metals and trash – and a high level of compaction (Evans et al., 2000). Because small urban plots are often intensively used, soil fertility is a constant challenge as will be discussed further below, and the incorporation of urban nutrients via vegetative or co-composting is a key area for PTD in urban agriculture. Nutrients for livestock production involve access to forage and other feed sources and their efficient use in livestock nutrition. These feed sources are often scarce in urban and peri-urban areas and this leads frequently to complex nutrient exchanges along rural to urban transects, for the benefit of both animal and crop production (Njenga et al., forthcoming).

Drawing own plots in participatory diagnosis in Montevideo

Water is also often a scarce natural resource in urban areas, and there is frequently intense competition between agriculture and domestic and industrial uses. "Resource recognition" is important in this context (Furedy 1992; Smit and Nasr, 2001). "Hidden" natural resources can be accessed, such as unused water surfaces and nutrient-rich wastewater (see Chapter 9, this volume). The notion of resource recognition is also important for accessing land, through use of vacant lots, unused public lands, and the composting potential of urban solid wastes (see Chapter 8, this volume).

Biodiversity is a key natural resource that supports agriculture. Population pressure, presence of contaminants and the fragmentation of green spaces in urban areas can severely reduce the resilience of plant and animal populations and their capacity for survival and for symbiotic interactions in ecological systems. PTD involves not only the identification of native species and varieties of plants and animals that are well adapted to urban soils and other conditions, but also the application of practices that enhance species resilience and symbiosis, for example, through biological pest control.

It is not always easy to differentiate natural and physical capital in the urban environment. Water, for example, is usually considered part of natural capital. Yet when it is cleaned and piped to the homes of urbanites, it becomes "adequate water supply and sanitation, which is part of physical capital according to DfID's literature on livelihoods. Organic wastes can also be considered part of the natural capital of the urban environment which is available for composting, yet when chemical fertilizer is packaged and purchased by households; it is usually considered part of physical capital. The important point here is not about trying to create watertight boundaries, but about the access of poor households to these different types of capital.

Physical capital includes the buildings, equipment, tools and physical inputs to agriculture and other activities, such as seeds, fertilisers, pesticides, animals, a small kiosk for trading, a sowing machine etc. PTD can have a direct impact on physical capital through improving the quality and fit of assets such as seed and equipment with the urban environment.

Financial capital refers primarily to the income available to the household from different sources, but also to loans and credit. (see Chapters 4 and 7) As already mentioned, households in urban and peri-urban areas are rarely dependent on a single income source. Different household members access different sources of income, and the same individual may also manage different occupations simultaneously. A common example would be a woman who is responsible for household food preparation and child-rearing, contributes to raising crops and animals and engages in petty trading (Arce et al., 2004).

Human capital includes labour, knowledge and the health status of family members and the ways these are deployed – or impaired – in livelihoods strategies. The local technical knowledge which household members utilise in agricultural activities is an important example of human capital. The depth of this knowledge, which is so critical in the management of complex rural farming systems, may be less obvious among migrants from totally different agricultural environments, or among non-agricultural households seeking ways to better secure family food security. Evidence from research with horticulturalists in Hanoi, Vietnam, indicates a reduction of use of toxic pesticides with greater time spent farming in a given environment, suggesting a growth in local knowledge of how to manage horticultural pests (de Bon et al., 2004).

Applied drip irrigation in allotment gardens in Cagayan de Oro

Human health is another key aspect of human capital that needs special attention in urban areas. Conditions in low-income areas of developing world cities often create health risks for the urban poor (Hardoy et al., 1990). Participation in agriculture can intensify negative health impacts on human health, through human and food exposure to contaminants and other illness-producing hazards in water, soils and animals (Birley and Lock, 1999). Health impacts can also be positive through nutritional and other health benefits of farming and farming products (Armar-Klemesu, 2000).

Social capital includes the access to and membership in social networks, groups and associations of different kinds, through which households gain access to other assets, such as knowledge, financial loans, labour and different kinds of support and security. Social capital also involves the trust that exists with others, which facilitates access to resources and enhances the sense of well-being and psycho-social health. Social capital is strongly gendered, in that social networks, trust, sharing and social support tend to be forged within the sexes rather than between, though important exceptions to this generalisation exist, including religious organisations. Relatively little work has been done so far on social capital in relation to urban agriculture, but there are examples of its contribution to community building, especially in the USA and Europe, and to improvements for HIV/AIDS affected communities (see Chapter 6, this volume). Research findings in both Latin America and Africa suggest that women play a major part in harnessing and maintaining social capital in support of crop and animal production (Maldonado, 2005; Maxwell, 1992; Chapter 5 this volume). The deployment of assets in household strategies, the influences and impediments which household members experience when they deal with urban institutions such as municipal regulations and policies or local marketing practices, and the livelihood outcomes which they achieve, are all part of urban livelihood processes. These processes in turn exert positive and/or negative ecosystem feedback on the livelihood assets and on the vulnerability context (see Figure 10.1). This means that efforts to develop physical and human capital through PTD need to take into consideration the effects of the technology on other household assets. For example, a technology involving high financial investment, such as drip irrigation, would reduce household financial assets that may be needed for other investments such as education or health care. PTD also needs to monitor the implications of alternative technologies for urban institutions and processes. For example, technologies for improving feed efficiency and thus profitability of pig-raising in locations where the municipal authority prohibits keeping animals (see the Hanoi case, Peters et al., 2002).

Whereas PTD in rural contexts has typically involved farmers and technicians jointly evaluating technology options in terms of their fit with the local farming and food system, the addition of an urban livelihoods systems framework locates the assessment of technologies in a more cross-sectoral, policy-sensitive setting. The rest of this chapter will explore a range of experiences evaluating technologies for urban use and highlight the way they have tried to adapt to different dimensions of livelihoods in the city

Participatory Technology Development: intensification and livelihoods

The wide range of farming systems found in urban areas can be differentiated in terms of types of intensification and their potential for positive and negative impacts on livelihoods. The urban setting encourages intensification and evidence suggests that the productivity of these systems is systematically higher than in rural areas (Yeung, 1987). Technology development needs to be focused on ensuring that intensification of both crop and animal production and processing offers maximum benefits to urban livelihoods and minimum negative impacts on the health of producer and consumer families, their neighbours and on the urban environment.

Agricultural intensification has usually been associated with the increase of output per unit of land area, through technical changes in crop management, especially the use of modern varieties and animal races, increased use of fertilisers and pesticides for crops, prepared feed, antibiotics and vaccines in livestock production, and improved water efficiency, especially via irrigation (Matson et al., 1997). Intensification in urban and peri-urban settings can be described as maximising output from minimal space. This also involves input technologies such as crop varieties and their combinations, seed management, animal nutrition, soil nutrition and water management. Pest and disease management is of major importance in some urban systems and almost ignored in others. Two aspects of intensification in the urban context which are less common or non-existent in rural agriculture (which will be considered later) involve the manipulation of vertical space³ and the recycling of domestic and commercial organic wastes as sources of soil or animal nutrition. This concerns technologies of composting or co-composting and the large-scale collection and preparation of restaurant and other food residues for animal feed, sometimes in combination with available forage. Although use of small quantities of domestic food residues is very commonly fed to animals also in rural areas, this urban feed system is unique in its scale and contribution to total feed input.

There are enormous differences in the way urban agriculture systems are classified, as is demonstrated in this volume (see Chapter 7, 11 and 12 for example). Classifications differ based on space (intra-urban/peri-urban), based on production objectives (subsistence/semi-commercial/entrepreneurial) and on predominance of crops or livestock and based on size of holdings. Most classifications capture a part of the reality but suffer from overlapping boundaries and geographical variability. In thinking about methods for technology development, it is important to think about the ways that different types of urban agriculture impinge on household livelihoods.

It is helpful to group together systems which mainly contribute in a positive way to household human resources through subsistence and enhanced nutrition, which also contribute in a limited way to the income of the family through small sales, or indirectly, through savings on purchased food. This contrasts with intensive semi-commercial or entrepreneurial systems which contribute an important, though not necessarily the major, part of household income, but because of the urban setting and the intensive methods can have negative health impacts on producer families and on neighbours and consumers. This is also an imperfect division, but it helps to organise thinking about key PTD issues in the urban context. In particular, it focuses attention on substantive differences in the manipulation of space and inputs.

Because of the somewhat different methodological experiences between crop and livestock production, these will be considered separately, even though mixed crop-livestock systems in cities are common and important for maximising recycling opportunities of crop and livestock wastes as fodder or manure.

The extent to which the policy and planning environment interacts with technology development also tends to vary between crop and livestock systems and between these two types of production system. Livestock-raising is subject to greater regulation and policy issues than crop production, and income-focused systems tend to be more policy sensitive than small-scale, "health and income support" systems. Policy factors are considered in a separate section.

Intensification and Sustainability of Urban Horticulture

A key technology development issue for urban horticultural production systems, especially on larger urban or peri-urban plots, concerns the sustainability of intensification strategies that farmers adopt, especially the extent to which these strategies impact on urban environmental health. Intensification of larger-scale urban horticultural systems occurs in at least three different ways with different associated health and environmental risks (see also Chapter 11):

1. Through cultivating high value crops during the off-season, to capture higher prices, through a combination of adapted varieties, increased use of pesticides and/or the use of physical barriers to control or avoid higher pest pressure. Risk factors are pesticide contamination and high cash investment.
    
2. Through productivity increases on the same land area in the same time period through modern varieties and/or increased use of agro-chemicals. Risk factors are pesticide contamination and nitrate leaching.
    
3. By maximising the use of available natural resources where these had not previously been used for agriculture, including use of wastewater, as a source of water but also as a source of nutrients (Cornish and Lawrence, 2001; Chapter 9), composted urban organic solid wastes and the use of abandoned or marginal lands, such as old factory or workshop areas, riverbanks or wetlands. Risk factors in this strategy are exposure to pathogens, parasites and heavy metals.

Technology innovation in these kinds of systems needs to adopt a broader urban systems approach to ensure that intensification contributes positively to individual household livelihoods – does not, for example, undermine human capital through pesticide poisoning – and also contributes to a more sustainable urban environment.

Intensified use of limited space

Some of the highest urban population densities are in developing world cities. For example, Manila City, part of Metro Manila, capital of the Philippines, has a population density of 41,000 people per square kilometre, almost ten times that of London. Very often the poorest families live in the most congested neighbourhoods and experience associated problems, such as health and difficulties in securing adequate food and nutrition for the household, because of high food costs. The poorest urban households spend as much as 80 percent of their income on food, up to 30 percent more than is spent by rural families (Argenti, 2000). With urban income frequently based on uncertain, intermittent employment, the possibility of utilising even the smallest spaces for intensive production of vegetables or small livestock can make a major contribution to the overall food security of these households.

Options and methods to maximise the agricultural productivity of minimal space vary along the urban-rural transect, with the greatest challenge existing in the most crowded intra-urban areas of cities where earth itself is lacking. In this situation, evaluation and innovation surrounds the conversion of under-utilised surfaces of the dwelling into mini-gardens.

This is the basis of container gardening, also referred to in the Philippines as "receptacle farming" (Undan et al., 2002). Rooftop gardening, as practised in many parts of the world from Manila to Russia to Senegal incorporates container gardening. This production method can provide an accessible and dependable source of leaves, stems, fruits, flowers and occasionally roots to supplement purchased food and to add micro-nutrients to starch-based diets. It takes advantage of patios, window sills, crevices and rooftops to locate any of a wide range of recycled domestic and industrial containers as recipients for soil and plants. Old tyres, tin cans, plastic bottles with the tops cut off, old water buckets, basins, baths, refrigerators and air-conditioning casings, biscuit boxes, fruit crates, bamboo poles, jute or plastic sacks with holes in the sides - the list goes on. As always with urban food production, human health risks need to be monitored in this method. Metal containers or paint cans can be a source of heavy metal contamination affecting humans and in some cases such as zinc, also plants. Metal containers can also absorb too much heat preventing good root growth. Two key technologies influence successful container gardening and need to be carefully evaluated: the type and quality of the planting materials and the quality of the planting medium. The economic benefits of container gardens are usually derived from the saved income from not purchasing vegetables in the market rather than from direct sales (Villamayor, 1991).

For these very low cost systems, accessing low- or zero-cost planting material is of major importance. A key strategy in PTD for facilitating access to planting material is through local seed networks, involving neighbouring households, schools, civil society organisations, agricultural extension services, city health centres and/or other local and national government offices. Social networks, especially linking women neighbours, do exist in urban settings (Arce et al., 2004) and seed transactions, if they don't exist already, can relatively easily become absorbed as a type of exchange in these informal networks⁴. In some cities, such as Dar es Salaam in Tanzania, Dhaka in Bangladesh, Manila and Baguio in the Philippines and Havana in Cuba, formal community or local government seed systems exist which supply seedlings at low prices to container and other types of urban gardeners (Jacobi et al., 2000; Gayao et al., 1997; Hellen Keller International, 1994; Cruz and Medina, 2003).

Indigenous species can more easily be replanted than exotic species, since the saved seed is mostly viable. Among African traditional leafy vegetables (TLVs), Amaranthus, Corchorus and Vernonia spp produce easily harvestable seeds which can be stored and reused, though the period of viability may be limited to as little as six months, and storage practices are sometimes problematic (Poubom, 1999). The production of seed of exotic, temperate vegetables is mostly a specialised activity in limited agro-ecosystems in tropical and sub-tropical regions, and seed must be purchased. Because seed of these species is usually sold in volumes much larger than is needed to plant containers in a small area, these are less commonly found in container gardens and usually linked to a community or local government seed system. Although there is much evidence about informal, reciprocal seed exchanges taking place between small rural households in the literature (eg. Tripp, 2001) there is limited information about exchanges among container and other kinds of urban producer. An early study in Kenya found that this type of exchange exists among different types of urban producers, but more commonly in the larger towns and cities (Lee-Smith and Memon, 1994). A recent study in Lima among small producers growing mainly for the market found that only about1 percent of producers obtain their seed this way, 18 percent reproduce their own seeds, primarily for local species, whilst the main seed source – especially for exotic and/or commercial species and varieties - is the commercial seed sector. Participatory technology development has been actively applied to the field of local seed systems (Scheidegger and Prain, 2000) and could contribute to enhancing access to and management of seeds in urban container gardening and other kinds of urban production systems.

The main factors of concern in managing container media are fertility, moisture control and aeration. A variety of techniques are available, and some examples are described in Table 10.1.

Although container gardens are adapted to densely populated spaces lacking plots of cultivable land, those same spaces are dense in usable nutrients: those deriving from the organic wastes and residues of the local population. Urine was identified as the most effective nutrient in Mexico, and it also emerged as the winner in participatory evaluations in the slums of Tacloban in central Philippines (Villamayor, 1991). Other sources of nutrients include food wastes, leaves collected from city trees and animal wastes from urban livestock keepers who sometimes find problems with disposal of these wastes (Njenga and Karanja., 2005). Evaluations of different nutrient options depend on local availability of organic residues of different types and the interest and resources of the container owner. Often there is either no space or no time for composting of household wastes, so urine is an attractive alternative. Where manure is easily available, as in Addis Ababa, maintenance of a stock of manure tea may be quite feasible.

Whether for container gardens or in less dense settlements where people have access to small backyard gardens or to off-site plots such as roadsides, riversides, wetland margins or unused public lands such as railway embankments and under power lines, opportunities exist for intensifying production. Intensification is dependent, as has been mentioned, on the interest and resources of the producer family, but it is also dependent on the regulatory environment. Even with sufficient resources, large investments in hydroponic or organoponic technologies is likely to occur only if there is security of tenure and supportive local policies (chapter 3, this volume). These issues are discussed in more detail in the final section of the chapter. In this section, alternative methods are briefly introduced which offer minimalist, low-cost solutions to intensification under constrained space conditions and often in an uncertain regulatory climate and informal social organisation.

BIG in Ethiopia, just outside Addis

Bio-intensive gardening seeks to intensify and diversify production through low-cost improvements in crop, seed and variety selection and sequencing, plant nutrition, soil management and pest management (Getachew, 2002; Chapter 11 this volume). The approach has a long history as a strategy for rural food and nutrition security (IIRR, 1991), but more recently it is being applied to the urban context. Bio-intensive urban gardens, in addition to the emphasis on enhanced nutritional quality of the food produced, adds a concern with food safety, given the increasing commercialisation of vegetables from high input peri-urban and truck farming systems. There is a strong emphasis on crop management and especially soil management, through simple techniques such as "basket gardens" and more labour intensive "double digging" of the garden bed with a mixture of 50 – 100 percent compost, for enhanced productivity (See the Case of "The Living Garden", Chapter 11, this volume).

The "pyramid" gardens introduced in Kampala and other cities are examples of the importance of manipulating vertical as well as horizontal space as a means of bio-intensification of small urban plots (cf. Niñez, 1984). Through collaboration between the Kampala City Agriculture Office and local women gardeners, pyramid-shaped structures have been constructed, using compost-enriched earth held in place by chicken wire and sacking. Holes are made in the sacking both horizontally, around the structure, and vertically, with the top part left open for additional planting. Such an arrangement allows the growth of many more plants than could be grown in a flat bed.

These practices are simple adaptations of two livelihoods realities present in many poor households in Addis, Kampala and in other cities in the developing world. On the one hand it is the common practice of planting horticultural crops in any available planting space, to supplement household food supplies and reduce cash expenditures on food, however modest. On the other, it is the existence of "hidden" household physical or natural capital – vegetative and animal organic wastes – which instead of being perceived as a nuisance and a burden, can be co-composted for use as soil nutrients to improve horticultural productivity. In Ethiopia, this simple connection has been made through hands-on practical training courses in bio-intensive gardening and through incorporating this and other types of bio-intensive technologies into NGO activities in and around Addis. In the case of intensive gardening in Kampala, although their introduction and use has been a result of close cooperation between the City Agriculture Office and women gardeners, the ambiguous status of cultivation in the city, with several by-laws prohibiting aspects of agriculture still in existence into the 21st century, the large-scale diffusion of these approaches has been inhibited, at least until a recent participatory review of the by-laws and ordinances and their revision by the City Council (DFID, 2006).

Urban horticulture as an income source and health risk: intensification and sustainability

A second, broad category of crop production systems in urban and peri-urban areas are those that seek to take advantage of close by, diverse markets through shorter growing seasons, higher yields and the production of the most profitable commodities. In this commercial intensification, these systems can interact in a number of negative ways with the urban environment, creating health risks to both producers and consumers and therefore becoming unsustainable. Risks include pesticide contamination, nitrate leaching, exposure to pathogens and parasites and contamination from heavy metals.

An integrated hydroponics system at Growing Power, Milwaukee

Technology innovation in these kinds of systems needs to adopt a broader urban systems approach to ensure that intensification contributes positively to individual household livelihoods – does not, for example, undermine human capital through pesticide poisoning – and also contributes to a more sustainable urban environment.

Farmer Field Schools, an approach which was developed for rural agriculture, has attempted to focus on eco-system learning and sustainable production systems, especially through integrated crop management.. It seems very appropriate for adaptation for use in urban conditions.

The Farmer Field School (FFS) method applies adult education thinking and experience to agricultural learning and change. Adult education has grown in importance as educators have recognised that the accelerating pace of technological change means that the tools one acquires in formal pedagogic education ⁽⁶⁾ become quickly obsolete in adult life (Minnick, 1989). FFS was developed initially to facilitate farmer understanding and application of integrated pest management principles in rice farming, for which conventional technology transfer training approaches were found to be inadequate (Röling and van de Fliert, 1998) and it was successfully introduced into rice farming in Indonesia and other Asian countries (ibid).

FFS has been applied to a broader range of crops, such as vegetables and has become less specifically focused on IPM, especially in cases where it is applied to crops with less stable demand and less clear agronomic constraints, such as sweetpotatoes in Indonesia (Braun et al 1997). This has led to considerable adaptation of the original production-side, crop constraint focus, with more attention to soils, markets, local learning and organization and farmer empowerment (Röling, 2003; Züger, 2005). In particular, it is possible to see how FFS is becoming more closely aligned with a livelihoods perspective, and less strongly tied to crop protection. In the words of Niels Röling, FFS is "a form of agricultural education that develops 'human and social capital' while conserving 'natural capital'" (ibid). This evolution of FFS seemed to align it very well with the livelihoods framework which is being increasingly used in urban agriculture research (Urban Harvest, 2004). The basic principles of the Farmer Field School, distilled from 10 years of Asian and other experience are listed in box 10.3 (adapted from Pretty, 1995)

FFSs provid

FFSs provide the setting and the materials for farmers to explore and discover for themselves new knowledge about agricultural production on the presumption that knowledge actively and repeatedly obtained in this way will be more easily internalised, retained and applied after completion of the training. Repetition is important for retention, which is one reason why FFSs are repeated, usually on a weekly or fortnightly basis, with the same structure, throughout the growing season.

Though some of these elements are as relevant and important for urban agriculture as they are for agriculture in rural conditions, some have special resonance in urban conditions. The approach requires a major time commitment by FFS participants which can be problematic in urban conditions where agriculture may be only one of several livelihoods activities.

Until recently the application of this method to urban conditions was largely untested (Prain, 2001). Yet it appears to offer the possibility of mitigating the negative consequences of intensification referred to above through safely and sustainably increasing the use of organic wastes for soil conditioning and plant nutrition and improving the management of pests and diseases through integrated approaches, leading to improved crop quality and food safety which are increasingly contentious issues in urban agriculture. It also offers the means to relate crop production to the broader socio-economic, institutional and policy arenas.

Case 1 of this chapter provides an example of the adaptation of FFS to urban horticulture in Lima, Peru. It shows that time is more of a constraint in urban settings and commitment is perhaps more closely linked to commercial opportunities offered by participation in the school. FFS also places strong emphasis on social interaction and learning, involving group activities. This can present difficulties in urban contexts where limited trust and social capital exist among urban cultivators (Arce et al., 2004). Yet as this case makes clear, though weak social linkages and other, urban-specific factors necessitate special attention at the beginning of the FFS process, the process itself provides a positive means to establish and strengthen social and communal ties within cities.

The case describes a project which was launched in 2004 by Urban Harvest and involved multilateral, national public sector, NGO's and community participation to mitigate urban poverty in the low-income eastern shanty towns of Lima through agriculture. Lima. The general objective of the project is to contribute to reduced urban poverty, improved food and nutrition security and a more sustainable urban environment through participatory, urban-adapted innovation in crop and livestock technologies and capacity building of the local population in sustainable and healthy urban food production. The experience of Farmer Field Schools within the CGIAR and especially within the International Potato Center, which convenes Urban Harvest, offered a model to address both urban-adapted innovation and farmer capacity building.

Urban and Peri-urban Livestock Raising: methods for addressing needs and mitigating risks

Throughout the developing world, and especially in Africa, animals are an important physical and financial capital for many urban and peri-urban households. They may be a regular or periodic source of income through sale of milk, eggs or off-spring, and they represent a form of savings which can be cashed-in if a crisis occurs. Animals also generate additional physical capital in the form of manure, either for sale or for improving the household's crop production system. Livestock are thus key components of livelihoods for many families and improvements in growth rate, health status and meat quality and/or reduction in costs of production through alternative diets using locally available ingredients can contribute directly and significantly to livelihoods (ILRI, 2005). On the other hand, keeping animals in the often cramped conditions faced by many peri-urban and especially urban producers is a potential health risk, not only to the producer's family, but also to neighbours and consumers (Birley and Lock, 1999) and chapter 12).

Goat keeping in Kampala

Yet in both rural and urban contexts, PTD for livestock has a much shorter history than for crops. A search on the internet for PTD in relation to crops and crop varieties, seed, soils, pests and diseases returns 5.5 million pages as opposed to 94,000 for PTD and animals, livestock and/or specific types of animals. Although situation diagnosis and analysis often includes livestock-raising and crop-livestock interactions, and looks at economic risks of the business, it less commonly incorporates environmental or health risk assessment associated with integrated systems. There are also far fewer cases of participatory experimentation for technology development. This is partly due to the fact that livestock research is still very much scientist-led and experiment-station based (DfID, 2005; Conroy, 2004), more so than crops research. Conroy also comments on another tendency within livestock research – to address the problems of, and work with, large-scale, commercial animal production and product enterprises, rather than addressing the often very different problems and needs of small-scale livestock keepers.

However, there are also methodological difficulties with participatory research with animals. Situation analysis may require different kinds of sampling, to capture different sizes of enterprises involving different kinds of animals and the variability of herd size over time, as well as including non-livestock keepers (See Case 2). This tends to favour the use of modelling, which allows the possibility of including these multiple variables, at lower cost. Where health risks are part of the diagnosis, minimal data on exposure to risk may require diverse sampling of animal substances and products. Although these difficulties also apply to situation analysis involving health risks in crop production, these are far fewer, and the more limited physical contact between human and crop reduces the exposure risk. The importance of exposure risk in livestock keeping suggests that there is more of a need for complementarity between participatory and non-participatory methods. In many cases, laboratory assessments, for example, need to be considered a component of the PTD process. Some of these issues are listed below.

• Experimental comparison of different technology options, such as animal cohorts undergoing alternative feed regimes, is complicated by several factors not present in the case of crops;
   
• Space constraints on-farm, limiting number of technology options or number of animals per option, which weakens the conclusions that can be drawn;
   
• Livestock management limitations, such as ensuring that "technology options" do not walk into each other's pens, thus confusing the conclusions that farmers and researchers can draw;
   
• High value to households of individual animals, leading sometimes to sales ahead of the completion of the trial;
   
• Practical difficulties and costs of periodic weighing on farm;
   
• Negative attitudes of local authorities or neighbours to the participant in research;

Many of these methodological problems are even more severe for urban livestock-keepers, where space is often more limited and the separation of technology options or treatments more complicated and where potential health risks from close animal-human interactions and the difficulties of disposing of animal wastes are greater. This tends to place greater importance on the use of statistical techniques to overcome these constraints.

The policy and regulatory context is often more difficult in urban settings, with controls or prohibitions frequently applied to livestock raising, leading to insecurity. Nevertheless, there have been some recent developments in introducing PTD into smallholder livestock research and at the same time reviewing the policy context in which technical improvement is taking place ⁷. The rest of the section illustrates these developments in Vietnam, Uganda and Lima.

Participatory experimentation: pig nutrition in Hanoi, Vietnam.

Feed is the main direct expense for pig-raising households in Hanoi, after the cost of piglets. Thus farmers seek ways to reduce their costs whilst maintaining or improving the health and growth rates of their animals. Situation diagnosis in a rural-urban transect linking Hanoi with its rural hinterland found three distinct pig production systems: mostly rural production of piglets, with sows fed on available agricultural residues, especially sweet potato vines; commercial fattening of pigs over about 30 kilos, mostly in the urban and peri-urban areas, and increasingly dependent on use of restaurant and other food residues from the city; in between these two systems, there is the specialised raising of young pigs (got) from about 7 kilos to about 30 kilos. This is the most entrepreneurial system, in that it carries higher risks from disease, but also higher potential profits. Profitability is related to growth rate, as well as the healthy, chubby appearance of the animals at sale, and these factors are highly influenced by diet. The original diet was based on purchased rice, rice bran, concentrates and a small amount of forage, mainly sweet potato tops. These inputs, most of which are enmeshed in a complex credit system, suffer significant price fluctuations, making the pig-raising family vulnerable to losses.

Furthermore, the rice needs to be cooked, thus increasing the costs and the labour investment. The PTD intervention in this context consisted in evaluating alternative, local feed sources, both for energy and for protein. In a series of three rounds of trials, two or three options or treatments, discussed and developed with the farmers, were compared with the current feed combination. Once again, as occurred in the example of Kampala, there is need to help construct a strong social network among farmer participants to establish a trusting environment within which to pool existing knowledge and experience and to ensure continued interest in participation. This was achieved through orientation and consultation meetings, sensitisation workshops, group evaluations of interim results and the encouragement of regular interactions among those involved in the trials. In Vietnam, there is a very strong local government system which supports to some extent the organisation of this kind of intervention, but there is also a need to create legitimacy for the intervention among the local cadres. An effective means to achieve this is through regular presentation of results to the local authorities and involvement of local authority representatives in knowledge exchange visits to other sites. This is important in any PTD intervention, but in political contexts where the local authorities control outsider access to households, it is essential. (Peters et al., 2002; Tinh, 2004).

Building capacity, institutional dialogue and policy support: Livestock groups in Lima and Nairobi

Within an urban livelihood framework, participatory technology development cannot be separated from PID: participatory institutional development. This is especially important for livestock-related PTD which is the target of much local regulatory attention. PID includes the need for capacity building, both to enhance efficiencies and to build awareness about safety and health issues. In Lima, a key component of capacity building for livestock production involves familiarisation with key indicators of animal health, development and feed needs and the maintenance of livestock registers, using the indicators to monitor growth and improve performance. This monitoring process is also being used by the R&D team to identify tendencies, in terms of feed use, health status or growth rate to propose technology intervention options. At the same time, this hands-on capacity building provides the basis for group formation around particular livestock and eventually formation of legal associations. This is part of a strategy to strengthen the capacity of local livestock keepers to link to new markets. Group formation can be a new process, working with independent households, or can build on existing structures, for example schools, churches or, as in the case of Lima, community kitchen-based women's groups. This group formation is closely linked in turn with institutional analysis, learning and change at the level of the local government, involving elected and appointed officials and representatives of other sectors (Arce, 2006).

Container roof garden in Manila, Philippines

In Nairobi, where urban and peri-urban livestock keepers make a major contribution to satisfying the city's demand for milk (Staal et al., 2002), they are also rather isolated from government services and vulnerable to regulation and harassment. In 2004, the Nairobi and Environs Food Security, Agriculture and Livestock Forum (NEFSALF) was established to:

• "drive the sectoral mix and interactions" among producer communities, government agencies, local government, the agricultural research community and the market, thereby improving institutional recognition and supporting commercial opportunities;
   
• acquire and target relevant knowledge;
   
• monitor process and monitor outcomes.

NEFSALF provides a platform to facilitate access by the community to provincial and municipal services and to open a dialogue with the City Council. It also provides the space for capacity building in key technical, health and policy areas, provided by public sector specialists. Currently the forum brings together 15 community groups mostly involved in mixed crop-livestock farming, government ministries, NGOs and local government representation (NEFSALF, 2005).

Integrated urban management of local agricultural development

In the urban setting, agriculture is one strand in a complicated web of activities in which households are engaged in pursuit of their livelihoods. Participatory technology development needs to assess the direct impact of innovations on household capitals and potential feedbacks to the urban ecosystem, affecting the capitals of other families. As the livelihoods framework makes clear, these innovations are also filtered through local institutions and policies which are more pervasive and invasive in urban areas than in the countryside. Urban PTD has a better chance of success if agriculture forms part of an integrated approach to urban development, with a supportive and enabling institutional and policy environment.

A useful example to consider, in which PTD has proceeded within an enabling policy environment, is Cuba. As Case 3 discusses in more detail, the growth of urban agriculture in Cuba and the uptake of innovative technologies have been dramatic and impressive. In just over ten years, between 1989 and 2000, it moved from a marginal component in urban food systems to a major category of land use in Havana and other cities, a major employer of urban labour and an important source of micro-nutrients for the urban population. It has also greatly reduced the accumulation of organic wastes in urban dumpsites.

Among the many instances of technical innovation which have accompanied this agricultural transformation, "organoponics" – the large-scale construction of raised beds for vegetable production using an enriched substrate of soil and organic matter – is a particularly important illustration of how institutional and policy integration facilitates technical change. Organoponics involves spatial intensification through the utilization vacant lots – frequently the concrete surfaces of demolished buildings. Facilitating this intensification are a series of policy changes about access to land, marketing of products and the structuring of the employment market. Bio-intensification, through an adaptation of the raised bed and double-digging techniques and the application of high levels of organic matter is again supported through institutional and policy mechanisms involving access to waste building materials to construct the beds and the provision of transport services to bring the large quantities of organic matter from the rural to urban areas.

Technologies do not stand alone. They need to be adapted not only to local ecological and socio-economic realities, they also need to be compatible with and supported by the local institutions and policies.

Concluding Remarks

Two important lessons emerge from the cases and experiences discussed in this chapter. For urban agriculture to be viable and sustainable, innovation needs to occur in the context of urban livelihoods, in which agriculture usually complements other employment and where agriculture contributes to and draws on the diverse set of capitals making up the household asset base.

Innovation also needs to occur at technical, institutional and at policy levels and to involve households, communal organisations and city authorities. It is this need for multiple innovation which seems to be more essential for urban than for rural agriculture. Cuba exemplifies not only the contribution of the city authorities to technical innovation in the organoponic gardens, but also the provision of a facilitating policy environment, in the form of relaxed restrictions on private access to and exploitation of land, new marketing systems and support for establishment of local level organisations (see the thrrd case).

Less successful aspects of the Cuban experience highlight other key elements of urban agriculture that need to be fostered. Technical, institutional and policy innovation need to result from participatory dialogue and negotiation, rather than being imposed by a single actor in the process. For instance, in Cuba there has been a tendency to impose a uniform use of high-yielding varieties, through a centrally-organised seed production system, even though experimentation with local land races or mixed varietal plantings could lead to benefits in some systems. Furthermore, there are indications that though urban agriculture has successfully produced food for several cities, it has not always become a well-integrated part of those cities. In the words of two Cuban writers, there is a lack of "harmony between the productive space and the constructed space" (Cruz and Medina, 2003). These observations raise an increasingly important theme in the urban agriculture discourse in both the North and the South. This concerns the multi-functionality of urban space and the opportunity for agriculture in the urban setting to fulfil multiple roles for the urban community (Chapter 1 and 7, this volume). The environmental contribution of agriculture has been widely documented. Already there is evidence that the psycho-social space which agriculture provides to poor households and communities in the city, and especially to women, can sometimes be as important as its food security or income role (Slater, 2001). Experiences cited in this chapter suggest that through the medium of field schools, urban agriculture can be a means for social organisation. There are also opportunities for agriculture to function as a source of child and youth education about natural processes and resources, as a locus for family recreation, and a major contributor to the sustainability of cities.

Notes

¹ This is not to imply that rural livelihoods are exclusively bound to farming. There is also diversity in rural livelihoods, but agriculture is still by far the dominant activity and often the only one (cf Ellis, 2000).

² In chapter 6 the authors identify seven capitals to illustrate Community Building Urban Agriculture (CBUA).

³ Tropical slash and burn or swidden agriculture is an important system that also manipulates vertical space (Conklin, 1975).

⁴ Nevertheless, social networks and other types of social capital may be less common in urban settings compared to rural communities (Stren et al., 2003)). This is discussed further in section below.

⁵ Manure dissolved in water.

⁶ Pedagogy literally means "to teach children".

⁷ The work of DFID's Livestock Production Programme (LPP) has made an important contribution to bringing participatory research into the mainstream of livestock programs in the developing world. See DfID 2005. The International Livestock Research Institute (ILRI), through its Small Dairy Development Program, has also tried to incorporate a participatory approach and to work with the small, informal sector where most dairy production takes place in Africa (Staal, 2002), and there are other examples.

8 This can be resolved through drawing a statistically random sub-sample from the survey sample.

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Situation Analysis and Health Risk Assessment: Cattle and poultry raising in Kampala

Gordon Prain

The Study

Livestock production within urban and peri-urban agriculture offers a wide variety of potential benefits (see also chapter 12). However, these benefits must be weighed against the potential negative effects of urban livestock production. The findings of a study in Kampala that examined the economic and health consequences of raising animals in the city are summarised here. The study was conducted among livestock keepers and included a sample of urban households that did not keep livestock (referred to as non-livestock keepers) as a control.

Pyramid garden and container gardening in central Kampala

Sampling of the three groups (cattle keepers, poultry keepers and non-livestock keepers) required preliminary and extensive key informant interactions, and helped to establish representative focus groups. Local knowledge and the residents' lists managed by the parish officials were used. In contrast to relatively homogenous rural communities, urban households tend to be more heterogeneous, having extremely varied livelihood activities. In this context it was essential to tap into local knowledge and the local social capital.

The information gathered through the focus group discussions was used to prepare a formal survey. Trade offs had to be made between statistically adequate sampling for the formal survey and the financial and organisational limitations on sample size for the health impacts assessment, which required taking a range of bio-physical samples (blood, milk, eggs). The collection and laboratory analysis of samples was necessary to verify health risks and to suggest participatory technology development (PTD) options. This underlines the interdependence in certain cases between participatory and non-participatory methodologies.

Cattle

The preliminary qualitative assessment identified cattle as the second-most important species for livestock activities in all areas of Kampala, after chickens. The benefits were ranked by focus group participants as follows: milk for cash income and home consumption; cattle sales (often for payment of dowry); manure for sale or use; employment creation. Milk production was clearly the most important benefit and this held true for both urban and peri-urban areas. Selling cattle, including for bride price payments, was considered almost equally important, especially in the urban areas and in some but not all peri-urban areas. Producing manure to sell or use in their fields was considered quite important by farmers as a secondary benefit in the peri-urban areas, but less so in the urban areas. Just over half (51 percent) of the households said they obtained more than a quarter of their household income from keeping cattle, particularly from the sale of milk.

Among the risks associated with cattle-rearing, the focus groups cited environmental pollution, accidents caused by cattle, straying of cattle in the neighbourhood leading to conflicts, low returns compared to farm inputs, flies being a nuisance, and zoonotic diseases. The zoonotic diseases specifically mentioned were tuberculosis (akafuba), brucellosis (okusowola) and tetanus. When the risks were ranked according to their perceived public health and economic importance, tuberculosis and brucellosis were ranked the highest.

These focus group findings were well-supported by the separate, in-depth qualitative studies of livestock keeping households using transect walks and in-depth interviews in two urban and two peri-urban parishes, and also by the formal survey. In all four areas, cattle were mostly kept in stalls or sometimes tethered, allowing women to supervise them while performing other domestic activities. Herds of cattle only occurred in the peri-urban areas. In the most rural of the peri-urban areas, cattle grazing on roadsides were being managed collectively by hired herders, while in a more densely settled peri-urban area herds grazed on open land at a community centre.

A farmer in Kampala who supplies a big supermarket in Kampala with green vegetables

Most respondents from both cattle-rearing and non-livestock keeping households were aware that consumption of raw cow's milk is risky, though they were not aware of the specific zoonotic diseases or drug residue hazards associated with raw milk. Despite this common awareness, consumption of raw milk was significantly higher among non-livestock households than in cattle-rearing households, suggesting that in the case of the non-livestock households awareness of risk did not necessarily lead to abstention. On the other hand, cases of household members diagnosed with brucellosis, which were reported in three of the cattle-keeping study households and the fact that 21 percent of the livestock households reported abortions in cattle, which can be a symptom of brucellosis, may represent sufficiently strong evidence of risk to lead to higher levels of abstention in these livestock households. Furthermore, only two out of 150 cattle-rearing households reported having vaccinated against brucellosis.

The situation analysis indicated that consumers of milk produced within Kampala District are at risk of exposure to both anti-microbial drug residues (â-Lactams) and zoonotic pathogens. Whereas some awareness exists that milk may be associated with health risks, the majority of those concerned knew little about the specifics of the various disease hazards, especially from anti-microbials. General ignorance of the latter and lack of effective control measures can be expected to contribute to cases of anti-microbial drug resistance (especially of â-Lactams) and allergies associated with such residues in foods (milk) in the city. With respect to zoonoses, this prospective study found a relatively high prevalence of brucellosis in cattle and the presence of E. coli in milk, indicating the need for more in-depth risk analyses and impact studies of these public health hazards, to guide the design of PTD, educational and/or policy interventions.

Chickens

Qualitative assessment of chicken-rearing activities indicated three categories: keeping layers for egg production; providing feed inputs to raise improved breeds as broilers for sale of live birds; and raising small flocks of local breeds using feed or scavenging. The third category also includes the sale of live birds. The focus groups identified benefits derived from rearing chickens and then ranked them using the pair-wise ranking technique. The general pattern that emerged across the different focus groups found the principal benefits, in decreasing order, to be: income generation; supplementary food for the household; and a source of manure.

Generally, Kampala households prefer eating the local free-range chickens and selling the improved breeds. The contribution of chicken production activities to household income varied between 19 and 76 percent, with a median of 38 percent. A pathway analysis of the production and marketing chain indicated perceptions such as the contradictory role of the municipal authorities (Kampala City Council) and the poor service provided by the veterinary drug sellers, including the high costs of the drugs. Also, marketing of chickens and eggs is sometimes performed by middlemen, which generates employment but also increases opportunities for contamination and human exposure to health risks.

The separate in-depth study on livestock production also confirmed the focus group findings for poultry keeping. Chickens were the most common form of livestock in all four areas, with all households keeping free-range local chickens for home consumption and more households raising exotic or "improved" breeds for sale of eggs or broilers. All households noted that the exotic breeds were more prone to disease although higher in productivity, and that the production of poultry for sale of eggs and live birds was on the increase in their area. Households rearing chickens in the two urban parishes appeared more conscious and concerned about diseases transmitted by livestock to humans than in the two peri-urban areas, with farmers in the central urban area even concerned about disease transmission from humans to chickens. They noted that keepers with flu could infect birds making them sick and unlikely to breed well and avoided contact with their chickens when they were ill.

Cowshed in Kampala

Women are the main caretakers of chickens in the household, (65 percent of the survey sample) and for 47 percent of respondents it is their main activity. For more than 80 percent it is a year-round activity with high rates of investments in vaccination.

Hygiene practices suggest that potential exposure to disease may be substantial. One in ten chicken-rearing households keep the chickens in their living quarters, and a slightly higher proportion allow the chickens to mix with other livestock. Less than a third wear protective clothing when working with their flocks.

Unfortunately, loss of the egg samples collected from the households due to spoilage prevented exploration of the correlation between the risk factors and the prevalence of one of the most common disease factors, salmonella. As a proxy for observations of the pathogen, the study documented reported incidence of enteric illness in the household in the two weeks preceding the interview. Although the use of the proxy suggested that keeping chickens does not contribute to significantly higher risk of enteric disease in Kampala, caution should be exercised in interpreting this result, given the poor quality of the proxy measure used and the small sample size.

In Summary

The central role of women in managing chicken enterprises may imply their higher exposure to potential zoonoses carried by the birds. Although observations suggested that such risk may be exacerbated by poor hygiene practices in many households, this was not confirmed by statistical analysis. The exception was when chickens were allowed to mix with other livestock; in this case statistical analysis confirmed that the practice contributes to higher incidence of enteric illness. The results of the analysis suggest that food practices in the household play at least as important a role as household chicken production in the risk of enteric disease. Specifically, eating raw eggs is associated with enteric disease, while eating meat-derived protein – including local chickens - and not eating leftovers are associated with lower levels of enteric disease. Finally, the linked study of livestock production systems suggested there might be higher awareness of health risks due to potential transmission of zoonotic diseases among the urban than among the peri-urban chicken farmers. These findings suggest the importance of PTD and educational interventions in poultry management and in household hygiene.

Note

¹ Based on Nasinyama et al 2004; Randolph et al., Forthcoming and Dimoulas and Walner-Toews, Forthcoming.

References

Dimoulas, Popy and David Waltner-Toews, Forthcoming. Household risk factors associated with rearing chickens in urban and peri-urban areas of Kampala. In Cole, Donald and Diana Lee Smith (eds) Urban Food Production and Public Health: What should towns and cities do?

Nasinyama, George William and Thomas F. Randolph, 2004. Characterizing and assessing the benefits and risks of urban and peri-urban (UPA) livestock production in Kampala City, Uganda. Final Technical Report to Urban Harvest and IDRC. Lima, Peru

Randolph, Tom F, Frank Mwiine, Delia Grace, Erastus Kang'ethe and George Nasinyama, Forthcoming. Characterization and assessment of the benefits and risks associated with urban and peri-urban cattle and milk production in Kampala. In Cole, Donald and Diana Lee Smith (eds) Urban Food Production and Public Health: What should towns and cities do?

Integrated Urban Management of Local Agricultural Development: The policy arena in Cuba¹

Gordon Prain

In the urban setting, agriculture is one strand in a complicated web of activities undertaken by households in pursuit of their livelihoods. As was argued in chapter 10, participatory technology development (PTD) needs to assess the direct impact of innovations on household capitals and potential feedbacks to the urban ecosystem, affecting the capitals of other families. As the livelihoods framework makes clear, these innovations are also filtered through local institutions and policies which are more pervasive and invasive in urban areas than in the countryside. Urban PTD has a better chance of success if agriculture forms part of an integrated approach to urban development, with a supportive and enabling institutional and policy environment.

A useful example to consider, in which PTD has proceeded within an enabling policy environment, is Cuba. The growth of urban agriculture in Cuba and the uptake of related and innovative technologies have been dramatic and impressive. In just over ten years, between 1989 and 2000, it has moved from a marginal component in urban food systems to an activity covering 12 percent of the land area of the city of Havana, involving a network of more than 22,000 urban and peri-urban producers, providing between 150 to 300 grams of fresh vegetables and culinary herbs daily and has resulted in the near elimination of local refuse dumps for household waste (Cruz and Medina, 2003)². Havana's agriculture involves a range of different systems and technical innovations (Novo and Murphy, 2000), but one of the most interesting from an institutional and policy point of view is "organoponics", an example of institutionalised spatial intensification and bio-intensification in urban areas, supported by the local authority.

Natural methods for fighting pests are very common in agricultural production in the city of Havana.

The development of organoponics and other organic and urban agricultural technologies are linked to what is known locally as "the special period" which followed the collapse of the Soviet Union and the resultant implosion of the Soviet-dependent Cuban economy (Rosset 2002). At the time of this collapse the Cuban agrarian economy was dominated by large-scale state farms producing sugar cane and other raw materials for export. In 1989, there was three times as much land under sugar cane as food crops and almost 60 percent of the calories consumed by Cubans were from imported food. Production of export crops involved conventional, high input agriculture in which 48 percent of fertilisers and 82 percent of pesticides were imported. The impact of the Soviet collapse was severely aggravated by the continuing blockade which the United States imposed at the time of the Cuban missile crisis in the early sixties. This "vulnerability context" to use the terminology of the livelihoods framework had a direct negative effect on livelihoods. Between 1985 and 1993, calorie intake per person/per day dropped by more than 30 percent to 1863 calories, well below basic nutritional needs. There was also a worsening of new born birth weight, nutritional status of pregnant women and other health repercussions, such as deteriorating public health due to failures in refuse collection.

Innovative livelihoods responses to the crisis occurred at both the level of households and within the political structures. "Patio agriculture" (see chapter 6), household aquaculture, vermiculture and crop-livestock production systems began to flourish and were assisted by local social organisations (eg. Federation of Cuban women and Committees for the Defence of the Revolution) and the emergence of farmers' groups. Institutional changes introduced by the government allowed citizens to become registered as self-employed and to register their businesses. This also involved the hand-over of 2.6 million hectares of land to cooperatives and allowed households and farmer groups to utilise idle land in Havana and other cities for productive purposes. Agricultural markets without price controls were also established. But the apparent key to the fast pace of innovation and transformation of urban agriculture from a marginal occupation to an important component of the national food system was the effort to ensure joint development of innovations by grassroots agencies and the government (Cruz and Medina 2003). An important institutional change to strengthen collaboration was the establishment of People's Councils as a new kind of grassroots government aimed at facilitating the participation of local households in solving problems (Cruz and Medin, a ibid). In terms of livelihoods (see Figure 10.1), the "policies, institutions and processes" which households must engage and negotiate with in pursuit of livelihoods strategies were considerably revised to facilitate urban agriculture as a viable livelihoods strategy. This is not to say that reforms of institutions and processes have been perfect. Empowerment of People's Councils to engage in economic relations and develop horizontal linkages with other entities is still incomplete (ibid) and the discourse of urban agriculture, especially in relation to smaller domestic spaces, is by no means fully embraced by Havana urban planners (Premat, 2005).

Organoponic gardens are particular examples of government-community collaboration in technology development and in management. Organoponics involves the construction of raised beds, which are then filled with a nutritious mix of around 50 percent organic matter and 50 percent soil, brought in from other locations, supported by local government (Novo and Murphy, ibid). Both "popular" and "high yield" organoponic gardens have become established, with different types of structures and management arrangements. The technology aims to bring inner city vacant areas which are either paved or have extremely compacted, poor quality soils into productive use. The popular organoponic gardens (POG) involve areas of between 2000 and 5000 square meters with lower investment in raised beds with simpler constructions of holding walls made of tiles, stones or recycled urban materials and filled with a mix of soil and organic matter. The high yield organoponic gardens (HYOG) in contrast involve higher investment in purpose-built structures of asbestos cement on areas generally around 1 hectare, with higher demand for water and requiring larger quantities of organic materials. Establishment and management of the POGs have been based on collaboration between municipal authorities and local neighbourhood groups or groups of workers. The former has supported the supply of inputs and the regularisation of output markets, which are often in the POG itself. The HYOGs involve collaboration between the city government, a state company and local organisations of workers in each individual HYOG. Local HYOGs maintain their own administration and pay a base salary to the members. This is supplemented depending on productivity, which is a strong incentive to innovate. The HYOGs also depend on the city and the state company to organise the supply of financing and material inputs and to support marketing.

Organoponics are all over the city of Havana

On-going technology innovation in these systems has been strongly associated with crop management practices, especially improvements in fertilisation using micro-organisms and biological control methods in integrated pest management (Rosset and Benjamin, 1994; Rosset, 2002). Cuba is a world leader in the production and use of entomopathogens, which are produced in different specialised, low-cost centres (CREEs), distributed through "corner shop" agricultural advice and service centres and widely utilised in the HYOGs, POGs and other types of production systems.

On the other hand, there is notably less innovation in the area of mixed planting and variety experimentation in the HYOGs (Cruz and Medina, 2003). The strong focus of both HYOGs and POGs on vegetable production leads to minimal or zero mixing of different groups of crops (leafy vegetables and root crops, fruit vegetables and aromatic herbs etc). In addition, the existence of specialised seed production facilities (Casas de Posturas) which formalise commercial seed production for the organoponic gardens, may tend to reduce the intra-specific diversity of varieties being grown (Rios personal comm.)

The importance given in Cuba to sustainable crop management practices came from recognition of the country's unsustainable dependence on export-oriented mono-cropping using largely imported inputs. The collapse of these imports in the early 90s – a 60 percent drop in pesticides, a 77 percent drop in fertilisers, petroleum for agriculture down by 50 percent (Altieri et al., 1997) – injected a dramatic urgency into the existing research efforts to develop alternative crop management options, leading to the successful outcomes briefly described above. (see also Chapter 11, this volume). However, the environmental and health benefits of biological and other forms of non-pesticide based pest control for the urban location are becoming recognised more slowly, as is the need for a more holistic view of agriculture within urban space. As Cruz and Medina observe:

"The existing design (of urban agriculture) does not favour harmony between the productive space and the constructed space, not only aesthetically..., but also in relation to other components of the urban environment, be they natural, economic or social... Furthermore, the interests of producers and those of the rest of the citizens, not directly associated with the results and impacts of the production activities, should be considered..." (Cruz and Medina, 2003).

These comments lead us towards the missing element in the Cuban experiment, but an increasingly important component in both North and South thinking about urban planning and the role of agriculture: namely multi-functionality (see Chapter 1 and 7 in this volume). This refers to the opportunity for agriculture in the urban setting to play multiple roles for the urban community, contributing to food security, nutritional well-being, income supplements for low-income families, child and youth education about natural processes and resources and the role of science, family recreation, and to the sustainability of cities.

Notes

¹ Synthesis based on findings of especially Cruz and Medina, 2003 and Novo and Murphy 2000, in addition to the other mentioned sources.

² The existence of a recently established alternative agricultural research agenda involving ecological principles, biological control mechanisms etc and linked to government import substitution strategy was also an important factor favouring rapid innovation (Rosset, 2002).

References

Altieri, M., P. Rosset and C. Nicholls. 1997. Biological control and agriculture modernization: Towards resolution of some contradictions. In Agriculture and Human Values. 14:303-310.

Cruz, Marìa Caridad and Roberto Sánchez Medina, 2003. Agricultura in the City. A Key to Sustainability in Havana, Cuba. Ian Randell, IDRC, Kingston, Jamaica.

Novo, Mario Gonzalez and Catherine Murphy, 2000. Urban agriculture in the City of Havana: a popular response to a crisis. In de Zeeuw, H. N. Bakker, M. Dubbeling, S. Gundel & U. SabelKoschella, eds. Growing cities, growing food. p. 329-347. Feldafing, German Foundation for International Development (DSE).

Premat, Adriana. 2005. Moving between the Plan and the Ground: Shifting Perspectives on Urban Agriculture in Havana, Cuba. In Mougeot, Luc J.A. (ed.), AGROPOLIS: The Social, Political, and Environmental Dimensions of Urban Agriculture. IDRC and Earthscan, Ottawa and London.

Rosset, Peter M., 2002. Posted: May 7, 2002Agricultura Alternativa Durante La Crisis Cubana. Food First, Berkely. http://www.foodfirst.org/cuba/agalternativa.html Last viewed 1 December 2005

Resources

Regenerating Agriculture: Policies and Practice for Sustainability and Self-Reliance.
Jules Pretty, 1995. Earthscan, London.
This book presents a compelling vision of an agriculture that is productive, environmentally sensitive and socially cohesive, and includes a wide range of examples of successful applications of innovative and sustainable practices developed by local communities partnered by research and development organisations. It also describes the kinds of policy environments which can support sustainable agriculture. There are discussions of integrated pest and soil nutrition management, soil conservation techniques and water management which are highly relevant for the urban setting, as is the extended discussion on farmer organisation.

Urban Livelihoods: A people-centred approach to reducing poverty
Edited by Carole Rakodi with Tony Lloyd-Jones, 2002. Earthscan, London.
This is a useful guide to the sustainable livelihoods framework as it can be applied to addressing urban poverty. It does not deal extensively with urban agriculture but includes an important chapter on rural-urban linkages and differences and the role of agriculture along the rural to urban continuum. Important contributions on human and social capital in relation to poverty reduction and on the role of municipalities are included.

Information and Communications Technology: Technology as Potential Catalyst for Sustainable Urban Development - Experiences in Eindhoven, Helsinki, Manchester, Marseilles and The Hague
L van den Berg and W van Winden (eds). 2002. EURICUR Series. Ashgate, UK: European Institute for Comparative Urban Research. 140 pages. ISBN 0 7546 1880 3.
By examining and comparing five European cities, this book sheds light on the impact of ICT on urban development and considers the consequences for urban management. The case studies show how cities use these new technologies to improve the delivery of municipal services, to increase civil participation and local democracy, to help their citizens and businesses make the shift to the information society, but also to fight the potential digital divide.

Environmental problems in an urbanizing world.
Jorge E Hardoy, Diana Mitlin and David Satterthwaite. 2001. London: Earthscan Publications, Ltd. 464 pages. ISBN 1853837 199 (paperback). www.earthscan.co.uk.
This updated and much expanded edition of the classic Environmental problems in Third World Cities describes environmental problems and their effect on human health, local ecosystems and global cycles. It points to the political causes that underpin many of these problems – including ineffective, unaccountable governments, and aid agencies' reluctance to work with the urban poor. It also highlights innovative solutions such as high quality, low-cost homes, neighbourhoods developed by poor groups working with NGOs and Local Agenda 21s developed by municipal governments in partnership with community organisations.

Participatory Research and Development for Sustainable Agriculture and Natural Resource Management: A Sourcebook. Three-volume Set
Edited by Julian Gonsalves, Thomas Becker, Ann Braun, Dindo Campilan, Hidelisa de Chavez, Elizabeth Fajber, Monica Kapiriri, Joy Rivaca-Caminade, and Ronnie Vernooy.. CIP-UPWARD/IDRC, Los Baños, Philippines.
Research and development can no longer be the exclusive domain of scientists. To find sustainable solutions to development problems, a wider range of actors must be involved. It is crucial, for example, that local stakeholders provide input to the process. Participatory research and development (PR&D) offers such an inclusive model. This three-volume sourcebook provides easy access to field-tested PR&D concepts and practices for practitioners, researchers and academics. It also presents a comprehensive overview of PR&D and will serve as a general reference for trainers, policymakers, donors, and development professionals. The sourcebook captures and examines PR&D experiences from more than 30 countries.

Feeding Cities in Anglophone Africa with Urban Agriculture: Concepts, Tools, and Case Studies for Practitioners, Planners, and Policy Makers
Edited by Marielle Dubbeling, Gordon Prain, Maarten Warnaars and Thomas Zschocke. CD-ROM, Urban Harvest-CIP, Lima, Peru.
Also web-based course at http://etraining.cip.cgiar.org.
This CD-ROM presents in interactive and accessible form the contents of an urban agriculture training course for Anglophone African countries conducted in 2004. The content includes a section on the history and concepts of urban agriculture and six modules on: Health Impacts; Crop production systems; Livestock production; Solid waste management; Wastewater use; and Integrating urban agriculture into urban planning and development. The modules can be entered directly, or via their relationship to key "Issues" in urban development, or via actor scenarios or through cities.

Sustainable Communities in Europe
William M Lafferty (ed.). 2001. London (UK): Earthscan Publications Ltd.
This book presents detailed research into the participation and involvement of local communities in 11 European countries. Overviews of implementation in each country are accompanied by comparative analyses of positive and negative changes to date. Useful examples of best practice case studies are provided, and crucial barriers to achieving sustainability are highlighted.

Sustainable agriculture, training of trainers: a resource book
International Institute of Rural Reconstruction (IIRR), 2002. 351 p. ISBN 1 930261 055 US$ 20 (inclusive CDRom). Available from: IIRR, Y.C. James Yen Center, Biga, Silang, Cavite, Philippines and ETC EcoCulture, PO Box 64, 3830 AB Leusden, The Netherlands. Email: Bookstore@iirr.org; www.iirr.org
This resource book is designed for trainers in sustainable agriculture. It has been developed as a response to the need to increase the capacity of training institutions in sustainable agriculture to impart and share the concepts, principles and experiences of sustainable agriculture. It brings together IIRR's 40 years of training experience and the results of a five-year Training of Trainers project on sustainable agriculture.

www.cipotato.org/urbanharvest/home.htm

Website of the CGIAR System-wide Initiative Urban Harvest on Urban and Peri-urban Agriculture, with updates on technical and policy work in Africa, Asia and Latin America, and links to CGIAR Centres and other urban agriculture websites.

www.prolinnova.net/circular.php
Prolinnova is a NGO-led global programme to promote local innovation in managing natural resources for sustainable agriculture. The site carries information on recent publications, reports, training experiences and materials related to PTD. All issues of the PTD Circular can be found at this site.

www.iirr.org
IIRR is an international NGO, headquartered in the Philippines, which specialises in running training courses on participatory methods, monitoring and evaluation approaches, policy issues etc.

www.livelihoods.org/index.html
Livelihoods Connect is a very useful resource centre for information on different uses of the livelihoods approach, with frequent updates on urban livelihoods issues

www.metrofarm.com
Metrofarm, the on-line magazine of metropolitan agriculture, is mainly focused on the US, with interesting discussions on health risks of commercial fruits and vegetables, profitable agriculture from small urban spaces etc.

www.ids.ac.uk/ids/particip
The Participation, Power and Social Change Team at the Institute of Development Studies (IDS), University of Sussex, UK, serves as a global centre for research, innovation and learning in citizen participation and participatory approaches to development. The website provides an extensive collection of material on issues related to participation such as theory and practice, citizenship and governance, policy, and organisational learning and change.

www.fao.org/participation/default.htm
This is the website of the Informal Working Group on Participatory Approaches and Methods to Support Sustainable Livelihoods & Food Security (IWG-PA) of FAO. The "Resources" part of the website has three sections: library, field tools and lessons learned. The website also supports French, Spanish and Arabic versions.

Although crops have always been grown inside the city, urban horticulture is expanding and gaining more attention recently. Horticultural products include a large variety of vegetables, cereals, flowers, and trees. Vegetable production provides regular and high incomes to the various actors in the commodity chain and provides food to urban dwellers. Many specific techniques have been developed or adapted specifically for urban areas. If well managed, urban horticulture can play an important role in reducing socio-economic and environmental problems in cities. Urban authorities should collaborate with urban producers to strengthen the role of urban horticulture in waste recycling, community building and creating sustainable food systems.

Urban Horticulture

Philippe Tixier

Hubert de Bon

Introduction

Urban and peri-urban horticulture (UPH) includes all horticultural crops grown for human consumption and ornamental use within and in the immediate surroundings of cities. Although crops have always been grown inside the city, the practice is expanding and gaining more attention. The products of UPH include a large variety of vegetables, cereals, flowers, ornamental trees, aromatic vegetables and mushrooms. Table 11.1 presents the main species cultivated in periurban horticultural systems and more specifically those presented in this chapter. The case study from Yaoundé, Cameroon, later in this chapter, is a good illustration of the large variety of species cultivated in UPH.

Generally, the types of crops cultivated vary according to the area, influenced by culture and tradition. In cities, short-cycle crops are preferred, while in the surroundings of the city crops with longer cycles are cultivated, for example in orchards.

Crops are grown in small gardens or larger fields, using traditional or high-tech and innovative practices. The major production systems and practices of UPH are described in this chapter, together with the major constraints (see also chapter 10). Some new techniques that have been adapted to the urban situation and tackle the main city restrictions are also documented. These include horticultural production on built-up land using various types of substrates (eg. roof top, organic production and hydroponic production), water saving in highly populated areas, the production of pesticide-free vegetables year-round with a low content of heavy metals and human pathogens, and control of wastes and leaching (fertilisers, pesticides, organic matter, water) in the urban environment. Urban and periurban cultivation systems differ from rural systems by their proximity to cities and by the constraints of space, which often lead to greater intensification of production.

The houses and of in-migrants will be much improved if they stay at the place long enough

Through the large variety of crops that are produced, urban horticulture makes a major contribution to food and economic security (see chapter 1 and 6). It also contributes to strengthening social sustainability and increasing ecological sustainability by transforming wastes, conserving natural resources, preventing soil erosion, and reducing pollution. UPH, like UA in general, has multiple functions. The main function is supplying fresh food, but emerging functions that are becoming more and more essential are economic (income generation), social (labour), cultural, living environment (open spaces and greening), environmental (recycling) and security (food and natural risks).

Although most of these species are not specific to periurban horticultural systems and can also be grown elsewhere, horticulture in urban areas minimises the transportation time for the supply of fresh produce to city dwellers. The cropping system in urban and periurban areas is usually adapted to the specific circumstances. Many traditional crops have been adapted to better respond to the needs of city consumers. Horticulture is practised for home-consumption but very often also for the market as high-value cash crops. In such a competitive environment, a focus on profitability may lead to improper management such as the intensive use of water, land and other (chemical) inputs, and thereby pose threats to humans and the environment. This issue will be discussed later in this chapter.

Table 11.1 Horticultural plants cultivated in urban areas

Policymakers around the world are showing an increased interest in urban horticulture, although their major focus is still on the temporary use of peri-urban lands. Periurban agriculture is encouraged in poor countries, mainly because it improves food security of poor households and the urban population's nutritional status (freshness of products and better access to fruit and vegetables, considered as a major source of vitamins and micronutrients), especially in view of the inefficient transportation and storage facilities in these countries. Policymakers also encourage UPH because it provides jobs and incomes to poor and landless urban dwellers and because it is well adapted to the urban environment where water and land are scarce.

Urban Demands for Horticulture

The proximity to urban markets often defines the production of specific fruits or vegetables, while there are also seasonal differences between rural and urban areas in terms of supply to the urban market. The case study from Hanoi, Vietnam, is an interesting example of how the horticultural market has evolved dynamically over the years in relation to social, climatic and cultural factors.

Fruits and vegetables for city markets are supplied from different areas: rural, peri-urban and urban, from within the country or from foreign countries. There is complementarity between the supply flows from the various origins, which may change over time. Products from UPH make up a very large part of the supply of vegetables to urban markets, such as in the capital city Hanoi (2.7 million inhabitants). Here, 80 percent of the vegetables (118,628 tonnes), come from the Province of Hanoi, an area of 7,095 ha of urban gardens (Mai Thi Phuong Anh 2000). In Brazzaville, 65 percent of the marketed vegetables come from its urban gardens (Moustier, 1999).

Factors such as climate, soil, access to water, insects and diseases, costs of production and, most importantly, the shelf life of the crop itself, influences the location of vegetable production. The last factor explains why, for most urban markets, leafy vegetables are produced in urban and periurban areas. In Brazzaville, the urban gardens provide 80 percent of the leafy vegetables for the urban market; in Bangui, 100 percent; in Bissau and Antananarivo, 90 percent (Moustier & David, 1997); in Dar-es-Salaam, 90 percent (SabelKoschella et al., 1998). Some leafy vegetables are well adapted to a hot wet season. The very short shelf life of cut flowers such as roses and chrysanthemums explains the development of these horticultural crops around Hanoi, where they are grown on 1,000 ha.

The season also influences the distribution of supply to the urban market from rural/urban areas. In Bangui, the share of tomatoes from rural areas increases from 40 percent to 50 percent in the wet season. In Bissau, the share of tomatoes from urban areas increases from 10 percent to 20 percent in the wet season. Urban horticultural areas may also supply the urban market more regularly than the rural areas. In Nouakchott, UPH supplies the urban market during nine months of the year, whereas the rural areas provide vegetables to the city only during three months (Margiotta 1997). Around Hanoi, choysum and leafy mustard are grown year-round. In Dar-es-Salaam, amaranth is grown throughout the year. This tendency to crop year-round is increased by the UPH producers' need to derive an income from various high-value crops throughout the year. This bias towards UPH may also be due to production constraints and access to transportation infrastructure during the rainy seasons or to socio-economic causes. In some countries, however, where flooding of urban areas expand every year, it is easier to find suitable spaces to grow vegetables in rural areas (Phnom Penh, Dacca).

Even if the consumption of vegetables per person is relatively low, consumer demand remains the major driving force behind UPH. In developing countries, the consumption of vegetables is generally lower than the FAO recommendation of 75 kg/year/inhabitant (205 g/day/capita). The importance of vegetable consumption depends on the population group. Over the period 1994–1998, consumption in Vietnam was higher in urban areas (182 g/capita/day) than in rural areas (122 g/capita/day), but lower than in mountainous areas (196 g/capita/day) (Nguyen Thi Lam & Ha Huy Khoi 1999). As is shown in Table 11.2, the consumption of vegetables in Bangladesh was higher in urban areas than in rural areas (Ali 2000).

Source: Ali (2000).

Urban consumption is related to the size of households, income and socio-cultural characteristics (Bicas 1998). In Africa, the most popular vegetables are tomato, onion and leafy vegetables, but there are location-specific variations. In Brazzaville, for instance, the importance of vegetables varies from one socio-economic group to another (Moustier, 1999).

Culture and festivals also have a very strong influence on consumer demand for specific products. In many countries, the main demand for flowers occurs on Mother's Day, Valentine's Day and during the Christmas period. In Vietnam, the Tet celebration is the opportunity to offer two ornamental trees: kumquats bearing mature orange fruits and peach trees in blossom. In urban and periurban areas in Hanoi, ornamental fruit-tree specialists have set up production to meet this demand, which means that they nurture young trees for a period of one year to prepare them for sale.

Source: Moustier (1999).

Factors Influencing Urban Horticulture

The development of horticultural systems in urban and peri-urban areas is determined by specific opportunities and constraints in the city. The constraints are mainly related to resource scarcity (water, land, labour and access to other inputs) and pollution.

Access to natural resources and labour

Access to suitable land is a key factor in urban agricultural development. Land ownership and tenure arrangements are important (see also chapter 3). In the large and fast-growing cities of developing countries, land pressure is great and often leads to rising prices. In this context, access to land by urban or periurban producers is difficult and poses a major constraint to their activities. As they are usually not landowners, they are obliged to rent from others or to squat on public land in order to have a small plot to cultivate. This uncertainty of land tenure has a strong influence on land-use strategy and maintenance. Producers may select fast-growing plants (such as leafy vegetables) rather than perennials (such as fruit trees); and may use places regarded as unsuitable for dwellings (such as swamps), which limits the range of crops that can be grown.

Insecurity of land tenure is a major problem that often leads to two types of responses by producers, who do not always take the long-term effects of agricultural practices into account. As a result they might choose inputs with strong and quick effects, such as chemical fertilisers and pesticides, rather than improving the soil using long-acting fertilisers and integrated production techniques. Producers may even turn to soil-less production systems on diverse substrata.

Looking after the greenhouse and picking cucumbers.

The size of plots is also a constraint. In the inner cities or periurban areas, horticultural crops are grown on very small parcels of land. This leads to the development of specific systems: intensive, high-yielding and year-round with the same or different crops. High yields require high use of inputs – water and fertiliser – combined with good light. The role of substrates to grow the crops is essential. As will be discussed later, different techniques have been developed for cases of little land or poor soil quality, such as hydroponics or organoponics.

Different sources of water are available in urban and periurban areas: potable water, wastewater, rivers, lakes and ponds. The specificity of horticultural systems is their adaptability in using these different sources, particularly the use of wastewater (see chapter 9). In all cases, this scarce source needs to be used efficiently and with precaution. Drip irrigation with different systems of micro-irrigation is possible. Use of a watering tank is more popular and is also one of the most efficient systems. The advantage of wastewater is that it provides nutrients together with the water. This saves the cost of fertilisers and labour to apply the fertiliser.

In urban areas, there is fierce competition for the use of land and water between horticultural activities and other economic activities. In a context of high economical competition, horticulture can be maintained if it generates more benefits than any other use of the resources (see also chapters 6 and 7 on this). Yet, even without intensification of production and even if it is less profitable, horticulture continues to exist, if its other functions (i.e. cultural) are valued by city stakeholders.

Another aspect of this competition comes from the many other human economic activities that occupy urban producers. In Hanoi, for instance, periurban gardeners seek jobs in industry, business and administration. Most often urban horticulture is a part-time job in this city, and different activities are combined in order to maintain livelihoods. The household members also divide their activities between production, sales and employment. The multiple economic activities of most urban gardeners may lead to a lack of sufficient labour during certain cropping periods such as planting or harvesting or for irrigation. The urban economy and its dynamics assign different responsibilities to women and men: women are often more involved in the cultivation and marketing (West Africa) activities than in rural and traditional horticultural systems.

Environmental pollution

Industry, services, traffic and high population density in urban areas are known to cause pollution to water, soil and air and reduce light intensity. A major challenge for urban agriculture, and especially for horticulture, is to supply safe products in this often polluted environment. In urban or periurban areas, the main pollutants of horticultural crops are heavy metals, pesticide residues, and biological contaminants. Such pollution presents a risk not only to the consumers, but also to the producers who come in contact with contaminated materials, for instance in wastewater. Additionally, these forms of pollution can be major factors in limiting crop growth. The problems occur mainly in areas close to active or old industrial sites, on urban waste disposal sites, when irrigating is done with water that contains heavy metals, fertilisers or organic matter, or when contaminated soils are used for cultivation. The source of human parasites are wastewater or animal wastes that are not composted (see chapter 8-9).

Heavy metals

The main causes of soil pollution from heavy metals (including lead, cadmium, chromium, zinc, copper, nickel, mercury, manganese, selenium and arsenic) are irrigation with water from streams and wastewater contaminated by industry, the application of contaminated solid wastes and the use of former industrial land contaminated by spilled oil and industrial wastes. Toxicity from heavy metals can directly affect plant physiology and growth and many cases of toxicity from heavy metals have been reported. For example, Jørgensen et al., 2005 show that intensive horticultural systems (particularly in greenhouses) in urban areas may be threatened by soil toxicity through trace elements such as Zn, Cu, As and Pb. The soils in many cities in developing countries have very high heavy metal contents. If the concentration of these elements in human food increases, it may cause toxic symptoms and cause damage to health (carcinogenic and mutagenic effects).

Organoponics in Cuba

The health effects and the heavy metal threshold concentration under which it is possible to practise safe agriculture have been subjects of much discussion. Puschenreiter et al., 1999 conclude that, having considered the several available pathways to reduce the transfer of heavy metals to the human food chain, urban soils with slight contamination by heavy metals can be used safely for gardening and agriculture if proper precautions are taken. However, Birley and Lock (2000) argue that little is known of the chronic health effects of consuming tiny amounts of heavy metals over long periods of time and that further research is needed. Mapanda et al., (2005) show that, in vegetable gardens of Harare (Zimbabwe), irrigation by wastewater may lead to significant heavy metal (Cu, Zn, Cd, Ni, Cr and Pb) enrichment in the soils. On the other hand, studies have shown that production in urban and periurban areas does not produce lower-quality vegetables than in rural areas (Midmore, 1998). Depending on the species and the plant parts, accumulation of heavy metals varies. Leaves can reach a high level while seeds are often less affected. It is possible to adapt the choice of crops in relation to the degree and type of contamination. Some horticultural crops such as beans, peas, melons, tomatoes and peppers show very low uptake of heavy metals.

The risk of pollution depends directly on the location of the fields. The rate of absorption of heavy metals by vegetables seems to be linked with their levels in the soil. Lead is taken up by the plant roots and is then transported to the leaves. Lead from traffic fumes in the air settles on the leaves. It can be washed away by watering the leaves, especially when the leaf surface is waxy (cruciferous plants, Alliums). Cadmium can be taken up by plants through roots and leaves. For these two very poisonous heavy metals with no positive biological functions, their presence in plants is controlled by respecting the soil standards. The location of vegetable production, with regard to roads and polluting industries, should be selected carefully. Bio-remediation of the soil by plants and installation of mycorrizae limiting heavy metal uptake are long-term projects that might help in management of heavy metals in the future.

In addition to heavy metals, air pollution too can contribute to crop toxicity. For instance, Agrawal et al. (2003) show that, in the polluted environment of Varnasi, India, some physiological characteristics of bean, palak, wheat and mustard are significantly affected by the SO₂, NO₂ and O₃ O3 concentration, which are very common. These gases are very common in large cities in developing countries, especially with the fast growth of personal transport.

Pesticide residues and fertilisers

As in many forms of crop production, horticulture is confronted with pesticide residues in the plants and pesticide exportation to the environment. This can lead to major health problems for producers and/or consumers. The residues of pesticides and fertilisers originate not only from agricultural inputs used by the producers. Cultivation in contaminated areas or irrigation with contaminated wastewater, also contribute to increasing the residual levels in plants above the allowed limit.

These contaminants are absorbed on soil and are characterised by a very long half-life. Most belong to families of products that are banned worldwide. The crops containing these pesticide residues are mostly tubers and root vegetables. For instance, in the periurban cropping system in the French West Indies (more specifically home-gardens), root vegetables (manioc, yam) grown on plots where organo-chlorine has been used, even many years ago, contain some residues and may constitute a risk to consumers' health. In this case the risk is further enhanced due to the improper management of land.

Biological contaminants

The contamination of crops with pathogenic organisms by re-use of urban wastewater and organic solid wastes is an important issue associated with food safety, especially in the context of UPH (see chapter 8-9). These diseases may affect the producers who handle the contaminated material, as well as the consumers who may eat contaminated fruits or vegetables.

In horticultural systems, solid wastes are mainly used to improve the soil (household wastes, market refuse, sewerage, night soil, manure, fish wastes and agro-industrial wastes). Urban organic wastes are mainly composted; this process significantly reduces health risks.

If the compost is not properly prepared (at a too low temperature), the organic wastes can still contain pathogens (bacteria, helminth eggs, etc). The risk is greatly enhanced if organic materials are mixed with human excreta from latrines, manure or hospital waste, causing pathogens to breed. The use of domestic sewage for irrigating and fertilising field crops, perennials and trees is widespread. A large part of the wastewater used is untreated or poorly treated and contains various bacteria, protozoan parasites, enteric viruses and helminths. Coliform bacteria are mainly transmitted to humans from wastewater via the contamination of crops irrigated with wastewater or through consumption of contaminated meat from domestic animals that have ingested tapeworm eggs from faeces in untreated sewage.

Pollution by horticultural practices

Horticultural systems may also pose a risk to their environments, and especially so in an urban context because of the proximity to people. Additional conflicts may arise between urban gardeners and city dwellers, especially when horticultural systems cause odours or, improperly, use large amounts of pesticides or fertilisers – artificial or otherwise – that urban dwellers fear may cause pollution. Although it is a general rule that inputs that affect human and environmental health must be used with care, this is more so in urban areas. The intensive use of agrochemicals (fertilisers, pesticides, fungicides) may lead to residues in crops, surface water or groundwater and cause negative effects to the health of agricultural workers.

Pesticides

All levels of cropping intensity are encountered in urban areas, from the most extensive (traditional) in developing countries and in allotment gardens, to the very intensive agriculture using high amounts of agrochemicals. Logically, the levels of pollution risk vary depending on the intensity of production.

Vegetables containing pesticide residues above the maximum residue limit have been identified in markets (Moustier 2000, Midmore 1998, Fatou Diop Gueye & Sy, 2001). In Accra, for example, a survey in 1998 of common cabbages collected from the retail market showed high residues of methamidophos, with two out of 20 samples exceeding the maximum residue limit (Sonou 2001). This occurs often, in spite of the fact that regulations for the use of pesticides and recommendations for health safety are in place. The application of pesticides on crops also endangers workers if little information is available on how to use them and when no protective measures are taken. This mainly affects low-income gardeners who cannot afford to buy proper protective clothing and equipment or are not aware of the importance of doing so.

Awareness of the risks caused by excessive use of chemical pesticides exists among all stakeholders, ranging from producers, consumers and public authorities to agrochemical companies. The UPH sector is more sensitive to this problem because of the proximity of consumer and producer. At this point in time, the penalties are not high enough to drastically reduce the over-use of pesticides. More negotiation between all players in the commodity chain might be one solution. In any case, there will be a cost, implying that the consumer must be ready to pay more to have a better-quality product and a safer environment. The development of new technologies such as integrated pest management and biological control can help in reducing pesticide use.

Nitrates

Nitrates deserve mention in pollution related to agriculture inputs. They can cause health problems to young children and pregnant women. Nitrates are also an indicator of good or bad agricultural practices. Nitrates cause eutrophication of water in combination with phosphorus. In Europe there are standards regulating the nitrate content in crops and water. In UPH systems, nitrates stem from fertilisation and from irrigation water. Some quick tests, such as Nitracheck®, appear to help producers manage nitrogen. Still, many of the methods available need to be validated for the specific urban and periurban leafy vegetables grown in developing countries. Moreover, with the aim of making better use of organic matter obtained from urban wastes in mind, specific tools need to be developed that take into account the problem of the irregular and slow release of nitrogen. If the source of pollution is close to the water resource, as is often the case with UPH, the risk of pollution of water by nitrates is enhanced. This is particularly true in developing countries that do not have a good network of water supply and where many people depend on the local water resources for their supply.

Recommendations for safe urban horticulture

De Zeeuw and Lock (2000) suggest a number of prevention and control measures that can be applied in UPH systems to help produce safe and healthy products. Such measures should help reduce risk of pollution of crops by heavy metals, agrochemical residues, pathogens and diseases. The general principle of these 'good practices' is often based on good communication between health sector actors and urban farmers, ensuring the latter is educated to respect rules to limit/stop contamination of the horticultural products. A summary of the major recommendations is presented below (see Box 11.1).

Agronomic Techniques

Horticulture in urban areas will continue to be adapted to specific circumstances, as determined by the opportunities and constraints, and specific techniques will be developed, including combinations of practices from traditional horticulture and more modern, innovative practices.

Horticulture is practised in various agro-ecological and climatic zones, from dry areas to tropical and equatorial climates, in areas with cold seasons and in those without. Urban producers strive to grow crops year-round, to be able to better regulate delivery. However, in different parts of the world, certain periods of the year are too cold or too hot to produce crops. Or the producer faces drought in arid zones and excess of water in wet tropical areas, mainly in the rainy season. Temperatures can be regulated by using greenhouses and plastic covers. In developed countries, vegetables are grown in greenhouses with a cooling system to decrease air temperature. In developing countries, the two main difficulties faced are excess of water or lack of water.

In tropical areas, the distribution of rainfall often varies greatly between the dry season, which is usually colder, and the wet season, which is usually warmer. In the wet season, heavy rains may stop horticultural activities even though the consumer demand is high. In solving this problem, producers in some areas, such as Martinique (French West Indies) and Mayotte, use shelters as "umbrellas" to prevent an excess of water for the crops. In some areas, despite the tropical location (eg. Réunion or Vietnam), heated shelters have to be used during winter when the temperatures are low. In some other cases, an insect-proof greenhouse has to be used to protect the crops (at least in its early stage of growth) from a virus frequently transmitted by insects. This is the case of tomatoes which can be infected by PYMV (Potato Yellow Mosaic Virus) and TYLCV (Tomato Yellow Leaf Curl Virus) through the white fly (Bemisia tabaci). These shelters help increase yields but require significant investment and may lead to side effects, such as the soil becoming too poor to further sustain production. Producers may need to turn to new techniques as described in the next section (organoponics or hydroponics). Producers, whether rural or urban, are always willing to adapt and improve their practices based on their own experiences and new information. Most of the new techniques however require access to capital for investments and access to specific knowledge.

Productive Micro Farm in San Luis Huexotla

Irrigation systems

Water is essential for the growth of plants. Water requirements are related to climatic conditions and plant species. In most capital cities of developing countries located in tropical and subtropical areas, the quantities needed vary from 0,1 to 1 l / m²/day in very dry and hot weather. For a crop of 30 days, the quantity of water needed by a leafy vegetable during the dry season is around 15 l/m². The case study of Dakar, Senegal emphasises the issue of water management in a context of limited availability.

Generally, water availability in cities has been showing a decreasing trend and the forecasts predict it will continue at least in the next 30 years (see chapter 9). Water is a necessity for crop production. Depending on the climate and the yields, producing 1 kg of a crop such as tomato requires 60–140 litres of water. Table 11.4 presents the approximate rates of water consumption of some horticultural crops.

Different techniques are used for irrigation. Water is applied by overhead irrigation using watering cans, and also through sprinklers or perforated pipes from wells, ponds or the sewer.

Vegetables, especially leafy ones such as lettuce and cabbage, need to be watered twice a day, every day or at least every other day to obtain a good quality (freshness, tenderness) for marketing. There are two steps in watering: 1) lifting the water or bringing it to the plots, and 2) applying the water to the plants. These two steps may be merged or kept separate. For UPH in developing countries, the watering can is the most commonly used system. Each can holds 8–15 litres; one worker usually carries two cans. The water is taken from shallow wells, deep wells, "céanes" in Senegal (which are wells fed by groundwater and often located at the bottom of slopes and strongly polluted by nitrates), small cement reservoirs, drums (Ghana) etc. Reservoirs are filled by hand using small buckets, or with treadle, electric or motorised pumps. In Vietnam, people irrigate by submersing the crop or by using small hand buckets to lift water from canals to fields. The manual system is efficient because, most of the time, the gardener applies exactly the quantity of water needed by the crop. It is labour intensive, and in Senegal, this operation takes 60 percent of the total labour requirement for vegetable production.

Drip or trickle irrigation is another irrigation technique that has been promoted for nearly twenty years. It saves water by 10–20 percent compared to overhead irrigation, but requires clean water in order to avoid blocking of the emitters. The fully-fledged system includes filters, pumps and a pressure regulator, which low-income vegetable growers cannot usually afford. The advantage of this technique is that water is not in contact with the fruits and leaves. It will not, however, avoid contamination of the soil and roots of vegetables with biological pathogens. Underground irrigation provides water to the plant by capillary action. Such an underground system can limit the transmission of pathogens to the vegetables thanks to the filtrating effect of the soil. But installation (flat soil) and operation (control of the flow to the plants) are rather difficult. Some simple drip-irrigation systems have been developed, e.g. in South Africa. This system consists of a 210-litre drum, which is connected via a tap to a set of five polyethylene dripper lines, each with a length of 6 m. The drippers are constructed by perforating the polyethylene pipe with a heated nail. A piece of string is threaded through these perforations by means of a bag-needle. Knots on both ends of the string prevent it from slipping out of the pipe. When the perforations get clogged, pulling the string from side to side usually unblocks the openings. Clogging of the drippers is reduced by placing a stone and sand filter at the bottom of the drum. The filter prevents coarse particles, which may be present in the irrigation water, from entering the pipes and blocking the drippers (Khosa et al. 2003). Such a system of micro-irrigation is particularly suitable for small farms in urban areas, because it does not need a high capital investment and because it uses rainwater collected from roofs.

Fertilisation

Crops require nutrients: macro-elements such as nitrogen, phosphorus, potassium, calcium and potassium; and micro-elements such as manganese, copper etc. Intensive cropping systems on very small areas, using only solid and liquid urban wastes, are not always optimal for crops.

Two main groups of fertilisers are used: organic fertilisers and chemical (or inorganic) fertilisers. There has always been a heavy use of organic fertilisers in intensive production such as vegetables and ornamental flowers. The quantity varies from a few tons/ha to 50 or even 100 tons per year. Organic fertilisers provide most of the micro-nutrients and in addition improve the structure of the soil. Organic fertilisers can be manure from livestock or poultry, compost from vegetable wastes or wastes from urban activities: sewage sludge, night soils, household wastes etc. Over many centuries, periurban and urban farmers have managed and recycled urban wastes (Fleury and Moustier 1999). In South-East Asia, use of fresh night soil is a common practice even though it disseminates human pathogens. These practices may cause some risks to the environment – pollution of soils with heavy metals from sewage sludge, pollution of water with nitrates due to large quantities of organic manure – and also to the health of the consumer.

Bucket Drip Irrigation in Philippines

Solid organic fertilisers have the disadvantage that they release nutrients, especially nitrogen, slowly. Liquid fertilisers act more quickly. This explains why liquid organic fertilisers are often used on short-cycle leafy vegetables like amaranth and mustard. In Hanoi (Vietnam), liquid organic fertiliser, eg. pig urine, is used to supply nitrogen during crop growth. Research has often focused combining organic and inorganic fertilisers to enhance their efficacy. AVRDC (World Vegetable Center) is working on producing an organic liquid fertiliser that does not endanger consumer health (AVRDC, 2000). The use of organic wastes as fertiliser can lead to different forms of pollution as discussed earlier. This problem is strongly linked to recycling in the cities (see chapter 8).

Inorganic fertilisers are easier to use and allow for application of the right dose of nutrients. However, there are risks of over-application and contamination of soils and water by nitrates and phosphates, which is especially relevant in the city. Also, they could be a source of heavy metals. In Thailand, it has been shown that ammonium phosphate can release cadmium, zinc and chrome into the environment in excessive quantities (Tran Khac Thi, 1999). Urea is the main inorganic fertiliser used in horticulture, especially for vegetables. There is often a lack of phosphorus and potash, and this can lead to an imbalance in the proportion of nutrients in the soil. However, the access to fertilisers in general and inorganic fertilisers in particular still requires a fairly high investment by farmers in most developing countries.

Pesticides

Chemical pesticides have contributed to yield increases in agriculture in general for more than 50 years. Especially in periurban horticulture, easy access to pesticides (via national and international companies, retailers and wholesalers) and technical information has increased its use. However, this has also increased the negative perception of agricultural production in and around the cities. There are three major risks involved: i) health risks for consumers; ii) risks of polluting the environment (mainly water sources); and iii) risks for users. Surveys have been conducted regularly on the use of chemicals, their rate of application and the period between the last application and the harvest for marketing.

In Vietnam, low-cost pesticides (organo-phosphates, pyrethroids, carbamates) with high toxicity (classes I and II) are very commonly used with little information about how to use them. Surveys shows that application rates are much higher than the recommended rates for most of the pesticides used. This and the high spraying frequency are the causes for high pesticide residues in the marketed vegetables.

Pesticides in the city's surface and waste water does not necessary come from urban horticultural production. Still when this water is used for urban crop irrigation, it constitutes a high risk. In Bangkok, a survey has shown residues of organo-chlorine and organo-phosphate in irrigation water (Eiumnoh & Parkpian 1998).

Urban Horticultural Systems

Rural horticulture adapted to urban situations

Kessler (2003) describes the different farming systems in four West African capitals (Lome, Cotonou, Bamako and Ouagadougou). In this study, the farming systems are characterised by the crops grown by farmers. The study reveals that differences in crops and inputs of the different farming systems are due to different economic strategies adopted by the farmers. Mixed vegetable farming with watering cans and/or with pumps to cultivate short- and long-cycle vegetables like lettuce, cabbage, carrots, onions, etc. is an example.

Similar systems are also described in Asia. Farming systems in the peri-urban areas of HubliDharward (India) comprise vegetable production, agroforestry systems, Napier grass (fodder) production and small-scale livestock production (Bradford et al., 2002). In Hyderabad (India), the predominant system is paragrass production, which like Napier grass is used as folder. Green leafy vegetables are grown here on small sections for subsistence needs and for sale. Other crops include rice, fruit trees and flowers. There is also coconut and banana as well as livestock (water buffalo) keeping (Buechler et al., 2002). In Cagayan de Oro (Philippines), urban types of agriculture are characterised by home gardens as well as aquaculture and other specialised food crops (banana, cereals, vegetables etc., usually as mono-crops). Production can be for home consumption as well as for market sale. Peri-urban agriculture is often dominated by irrigated vegetable production, as is the case in Vietnam or Malaysia. Other systems that can be counted are commercial and domestic livestock production, flowers and seldom agroforestry (Potutan et al., 2000; own observations). Major systems mentioned for Shanghai are cereals, vegetable and livestock production (Yi-Zhang and Zhangen, 2000).

Organoponics in small buckets

Many additional types could be named using the major crops grown or animals raised as a criterion. A study under the Urban Harvest Programme (www.cipotato.org/urbanharvest/home.htm) in Cameroon identified three major types of cropping systems:

1. mixed crop systems dominated by open-pollinated varieties (OPVs) of improved maize in the upland areas (vacant lots, unused municipal lands);
    
2. mono-cropping systems of OPVs of improved maize grown in valley bottoms; and
    
3. intensive horticultural systems in valley bottoms, primarily for the production of traditional leafy vegetables (TLVs).

In addition, they observed that there is widespread use of small home garden plots for growing leafy vegetables and stands of banana, plantain, avocado, African plum and other fruit trees around homesteads. Within these cropping systems, the research identified two types of agricultural units: "commercial" and "household food" producers based on the criterion of producing for sale, at least, half of the output from one of their products. The study found that women are the main producers for both household food and for sale, accounting for 87 percent of the total sample (see also the case of Yaounde).

Moustier in chapter 7 summarises the different descriptions found in literature of cropping and farming systems in 5 major types of urban agriculture:

• Subsistence home intra-urban farmers (intra-urban and peri-urban areas)
• Family-type commercial farmers (intra-urban and peri-urban areas)
• Urban and peri-urban agricultural entrepreneurs (intra-urban and peri-urban areas)
• Multi-cropping peri-urban farmers (peri-urban areas)
• Urban residents with speculative strategies (intra-urban and peri-urban areas)

Although quantitative data on the importance of each of these types are scarce, available figures for West and Central Africa suggest the dominance of family commercial farmers in terms of number and of importance in urban food supply (Moustier, in chapter 7). In Dakar, out of 5025 urban farmers, 70 percent were family commercial farmers, 25 percent were entrepreneurs and 5 percent were subsistence farmers (Mbaye and Moustier, 2000). Households may move from one category to another, for instance when products are being sold in the market. The (semi) commercial households' main aim is to have a regular income and a regular food supply for securing their livelihoods. Therefore the cropping system is based on crops that add high value and that are less risky to grow on small parcels of land. Leafy vegetables with short cropping cycles that enable regular cash generation are a typical example.

New Urban Horticultural Systems

New horticultural practices have been developed to maximise the use of space, to optimise the use of inputs and to minimise impacts of horticulture on human and environmental health. Some of the new techniques described here are: growing horticultural crops on urban built-up land with various types of urban substrates (eg. on roof tops, organic farming and hydroponic production), to save water in highly populated areas, to produce pesticide-free vegetables year-round with a low content of heavy metals and human pathogens, and to control wastage and leaching (fertilisers, pesticides, organic matter, water) into the urban environment.

These techniques take into account the specific constraints of UPH systems, but are more demanding than traditional or conventional techniques in terms of new knowledge and/or investments.

Hydroponics

Hydroponics is a technology characterised by the absence of soil. It needs less space, labour, external inputs and time, but needs proper management and often higher investments. As mentioned earlier, it is often difficult to control or quantify nutrient availability in the soil. Hydroponic systems provide a convenient means to control plant uptake of nutrients. An additional advantage of water culture is its secondary effects such as accumulation of soil toxins are likely to be reduced (Lissner et al., 2003). Another advantage of growing without soil is that it reduces some soil-borne diseases.

The basic concept of hydroponics is that roots suspended in moving water absorb food and oxygen rapidly. Of special concern is the availability of oxygen. The grower's task is to balance the combination of water, nutrients and oxygen with the plants' needs in order to maximise yield and quality. The use of water and inputs is optimised: the exact amount needed by the plants is provided. For the best results, a few important parameters need to be taken into account: temperature, humidity and CO₂ levels, light intensity, ventilation and the plant's genetic make-up. In order to fix the crop roots in the required position, some inert substrata may be used (sponges, artificial mineral marbles, rock wool etc).

Water quantity and quality are key factors in hydroponic systems. Water quality depends mainly on the source used. Growers use water from different sources, such as surface water (lakes, natural and artificial ponds), groundwater (wells), municipal tap water, rainwater and combinations of these. Rainwater has a low ionic strength and usually low micro-organism and algal densities; it conforms to water quality guidelines and is often better than other sources. A common practice is to collect rainwater from greenhouse roofs into ponds. However, as these ponds are fed by atmospheric precipitation, they are vulnerable to changes in the environment, eg. eutrophication and acidification. Rainwater is not always available for use in irrigation because of technical problems in collection and storage. Therefore, the grower must find other water sources, eg. rivers or lakes, but, in many cases, such sources are polluted (Schwarz et al., 2005).

Hydroponics allows production in abundance of healthy fresh vegetables, ornamentals, aromatic and medicinal plants and suits the requirements of poor urban farmers. When the technique is well controlled, the productivity generated by hydroponic systems is greater than that from traditional gardening systems. It is a perfect technology for urban or periurban areas where the soil is poor or polluted. In many countries of South America, hydroponics is a technique that is fast gaining importance (Tabares, 2003; Rios, 2003).

Small hydroponic units can be operated by families. This may help in meeting their food needs and in getting an additional income. Some special hydroponic techniques have been developed, especially for limited spaces and to suit people in developing countries. Such simplified hydroponic systems often use recycled materials and are easier to understand, learn and implement (Caldeyro-Stajano 2004). Simplified hydroponics is a technology incorporating soil-less culture techniques without using mechanical devices or testing equipment. This technology was developed in the early 1980s in Colombia and is propagated by FAO. It is accessible to people with limited resources and is optimised to use minimal inputs of land space, water, nutrients and grower infrastructure (See Box 11.2). A Family Economical Unit (FEU) of 20 bed-growers of 2 m² each (40 m²) is designed to produce crops that bring an income estimated at USD 3.33 per day in Colombia (year 2000 figures). Simplified hydroponics is well suited to fresh vegetables and fruits (with a high water content) such as lettuces, tomato, bell pepper, basil, celery and radish.

Another interesting process is hydroponics with floaters, where plants are fixed on polystyrene beds that float over a tank. The water surface is completely covered by the floating bed which permits a very limited growth of algae. The tank's nutritive solution is oxygenated, eg. by a pump. This hydroponic system is characterised by a large volume of nutritive solution, no losses of water, minimal evaporation and the possibility to use the solution for many crop cycles. It is a low-cost method needing little maintenance. It is used in Martinique (French West Indies), an island with high constraints of space in periurban areas, for production of lettuce or onion (Langlais, CIRAD, pers. comm.). Hydroponic systems also present interesting solutions in combination with the recycling of water, and has been studied in water hyacinth, reed and flower (roses) production systems. Another possible future development of hydroponics is the production of bio-energy crops using wastewater as a nutrient solution (Mavrogianopoulos et al., 2002).

A large variety of crops can be grown on a small area

The use of wastewater in hydroponic systems requires monitoring of the water quality. The Gravel Bed Hydroponic system (GBH) developed by the University of Portsmouth, UK, includes a rock filter in gabions for primary treatment, GBH beds for secondary treatment and a pond for tertiary treatment. It reduced the biochemical oxygen demand (from 350 to less than 20 mg/l) of the output water in a bed planted with narrowleaf cattail (Typha angustifolia) in Colombia (Stott et al., 1999). Williams et al., 1999 also show that the use of GBH in Egypt permitted a significant removal of parasite eggs from domestic wastewater.

Organoponics

Organoponic systems grow crops on organic substrata to replace unavailable chemical inputs. The crops are sown in holes or furrows filled with an organic substratum, the concentration allows maximisation of its effect. The origin of the substratum can be diverse, including compost or organic residues from other sources (faeces, wastewater residues etc). The technique is widely used in Cuba and Venezuela.

Organoponics is particularly suited to soils of very low fertility; in the long term, it helps restore the soils by increasing the soil organic matter content. It is also well suited for vegetable production in urban and periurban areas because it maximises the use of space and water. However, in an urban context, the supply of organic substrata can be limited. Depending on the origin of the substratum, some pollution and sanitation problems may be increased, especially when solid waste compost that could contain heavy metals is used. Linking horticultural organoponic systems with ecological sanitation (as described in the Urban Agriculture Magazine no.10) or use of manure, could increase the productivity of organoponic systems.

Green buildings

In developed countries, covering buildings with plants (green building strategy) is part of the ecological design of urban landscapes and is becoming increasingly widespread (Calkins 2004). To be a nutrient capture system, to recycle organic waste and to provide employment, rooftop growing must be profitable. Wilson, G., (2002) shows that in the medium-term urban cropping systems may generate a positive net gross margin. In developing countries, horticulture on buildings, mainly on rooftops, is gaining in importance and allows production of various vegetables, fruits or flowers. For instance, in Senegal rooftop gardening, based on bricks or wooden box beds filled with compost, allows growing a wide variety of crops, including: fibrous roots crops, tomato, hot pepper, eggplant, etc. (Deesohu Saydee and Ujereh, 2003). Such cultivation is characterised by its high level of intensity due to very small spaces available on the roof of buildings. They use either hydroponics or organoponics (often in containers, boxes, pots or cells). A positive effect of rooftop gardening is that planted roofs improve the thermal performance of a building. They block solar radiation and reduce daily temperature variation and thermal ranges between winter and summer (Eumorphopoulos and Aravantinos 1998). The effect of rooftop gardens on reducing the energy consumption of commercial buildings was measured to be up to 14.5 percent in Singapore (Wong et al. 2003). Singapore has developed a project of greening by planting trees, shrubs and grass in the city in order to maintain a pleasant living environment. Roof gardens, though not a new concept, increase the percentage of greenery in urban built-up areas and bring back the vanishing urban green space. Sprucing up the originally under-utilised portion of the buildings, they can 'create a new network of vegetation linking roofs' and increase the ratio of greenery to people.

Due to being located outdoors, these systems face natural attacks, e.g. of insects and birds, and some crops would therefore need protection. The issue of the crop residues produced by such systems is also a consideration in the urban context and could be a limiting factor in the development of agriculture, if not accounted for in urban planning.

Permaculture

Due to the limited area for cultivation and the constraints this poses, agricultural activities within the city have to be efficient and with minimal impacts on the environment. Some integrated systems called 'permaculture' have been developed to meet these requirements. They combine growing fruits, vegetables or grains with keeping livestock by creating a symbiotic ecosystem, with an ethical foundation in sustainability and copying nature, and a scientific basis in ecology. Permaculture (for permanent agriculture) is particularly relevant in the context of UPH because it is a flexible option that suits city conditions due to the local recycling of energy and resources. The variety of production limits the risk and gives financial security. It is well suited to the developing countries because external inputs (chemical fertilizers, pesticides etc) are limited or absent.

Permaculture can be considered as one ultimate cropping system concept that uses a wide range of techniques and concepts: rainwater collection, excrement composting, reusing and recycling resources, saving energy, green building and planning, developing the local economy. For example, in London (UK), Becontree Organic Growers in Dagenham develop the local economy through a local exchange trading scheme (Sherriff and Howe, pers com.). In Havana (Cuba), permaculture has been encouraged (Lazo and Barada, pers com.), where it has not only permitted the production of food, medicinal plants, spices and ornamental plants, but also resulted in a knowledge network by including a range of interested actors through periodic workshops, courses and conferences in environmental education and other related topics.

Simple Hydroponics at a school in Peru

Conclusion

In many expanding cities in developing countries, UPH is already a large contributor in supplying fresh produce to city markets and is expected to remain so in the near future. On the one hand, the available land will decrease because of the need for industrial development and urban housing. On the other, the demand for fruit, vegetables and flowers will increase with rising standards of living and growing populations. Horticultural production units will evolve and adapt to new environments as cities continue to develop. In the future, vegetable production will remain essential as a source of high income and healthy food for growing cities.

Vegetable production provides regular and high incomes to the various actors in the commodity chain and provides food to urban dwellers. For instance, in 1999 in Jakarta (Indonesia), UPH fruit production supplied almost 20 percent of the city's demand. Worldwide, about one quarter to two thirds of urban and periurban households are involved in agriculture. In the coming decades, fruit and vegetable production will continue to play a key role in feeding cities and providing activities and incomes to farmers. To answer consumers' demand and to produce healthy fruits and vegetable in a manner that respects the environment and producers, it will be necessary to combine agro-technical solutions with urban planning. Many specific techniques have been developed or adapted specifically for urban areas but there is still some research needed in order to better understand these complex anthropised agro-systems. Systems such as permaculture that combine various forms of production can be very complex ecologically. It is therefore important to undertake agro-technical studies that could provide more in-depth on the conditions required for obtaining good-quality vegetables. Urban planning should help to provide optimal conditions for urban gardeners (See chapter.3).

So, with a view to current and future technology transfer, all stakeholders in the commodity chains have to be involved in developing better conditions for integrating fruits, vegetables and flowers as part of UPH. Supply of inputs and materials, management of crop residues and linkage between activities are key points that need to be taken into account early in the urban planning process. It involves all aspects of a city's organisation and requires commitment to provide goods and services to agricultural activities and people (Pinderhughes 2004), (see also chapter 1 and 2). The case of PROVE (chapter 7), also shows that additional income can be gained by (poor) urban producers if less intermediaries are involved in getting their products to the consumers.

Various functions of UPH have been mentioned in this chapter. The food supply function remains the most important, even though economical, social (labour), cultural, living environment, environmental (recycling) and security (food and natural risks) functions appear to be essential too. More than any other agricultural system, UPH has a multifunctional role that should be taken into account by researchers and policy makers. Implementation of an urban planning policy that includes the sustainability of this form of agriculture is a necessity for well-balanced urban development. UPH plays a substantial role in the development of local (micro)enterprises, including input supply, processing and marketing. It also reduces the distance that fresh food needs to travel from producer to consumer.

If well managed, urban horticulture can play an important role in reducing socio-economic and environmental problems in cities. Planners and policymakers should develop and support community-wide plans to improve poor people's incomes using urban organic waste, to improve urban food safety and to create sustainable food systems.

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Dry and aquatic peri-urban and urban horticulture in Hanoi, Vietnam

Hubert de Bon

In Hanoi (2.8 million inhabitants, 921 km²), horticulture is practised all over the city. Hanoi Province is divided into seven urban and five periurban (or rural) districts. The mean farm size varies from 1600 m² in urban districts to 3200 m² in peri-urban districts. The average household labour involved in horticultural production is around one person in urban districts and 1.5–2 persons in periurban ones. Hanoi is surrounded by rivers which flood during the wet season from June to November, and is a significant constraint to horticulture. Despite the humid subtropical climate, all crops are irrigated.

In urban districts, the main crops are leafy vegetables (kangkong, Chinese water spinach, water morning glory and choysum), flowers and ornamental citrus tree (quat). Kangkong is grown in the Hanoi area, in the two urban districts of Than Xuan and Dong Da, as well as in the Thanh Tri southern peri-urban district. Kangkong (water convolvulus) is grown in water and in a dry system. The aquatic production occurs in lowland areas and canals filled by rainwater and sometimes domestic wastewater from the surrounding houses. In the urban districts, the main sources of wastewater are city drainage and households. Whatever the quality of the water, kangkong grown in water is considered to be the best. The growers are essentially older women. In the two urban districts, only five families are occupied with this production, which contributes only part of their household income. Harvesting is done every two or three weeks; the young shoots of 30–40 cm are cut and sold by the bunch. Sometimes, pesticides are applied on the foliage. The produce is sold directly in the street markets or, during the main harvesting period, at the wholesale night markets in bulk.

Water mimosa production

Ornamental plant production has developed in connection to the Tet (Vietnamese New Year) celebration. Citrus kumquat with orange fruits and blossoming peach trees are traditional gifts for the Vietnamese New Year. All around the lake Tay Ho, just before Tet, there is tremendous activity in sales of ornamental potted trees and blossoming peach-tree branches. Usually, the potted trees come from nurseries with a nine-month cycle in the inner districts of Hanoi. The young trees are brought from areas further away in the eastern provinces, such as Hai Dung, and transplanted in the nurseries of Hanoi. The Hanoi cycle demands large quantities of soil which are brought every year, between the Tet harvest and the time of transplanting. Many lorry loads of soil are dumped around the lake in order to replace the 10-cm layer of soil removed by the production of trees for the Tet festival. Uniformity in the size of the orange fruits is obtained by applying hormones. The pyramid shape of the trees is gained by tying up the lateral branches with wire.

In the five peri-urban districts, vegetable production is very diverse with many specialised niche markets. Around 100 vegetable species are grown. For instance, the wax gourd (Benincasa) is grown mainly for small enterprises that produce crystallised fruits also sold during the Tet festival. Gherkins are grown for pickles. Recently, rose production for the local market and for export to China during the winter season has developed very quickly to reach around 1000 ha of production in the Tu Liem District. Thus, there is horticultural production that feeds the processing and export sectors which take advantage of the city infrastructure (railway station, roads, access to power and services). On the other hand, there is also the cultivation of species that require short marketing chains from harvest to consumer, such as choy sum, Indian mustard, garland chrysanthemum, amaranth, lettuce and young shoots of squash. In this type of production, the grower tends to apply diverse chemical pesticides in order to obtain a good green leaf free of insect and disease damage. Thus, it is necessary to develop techniques that will reduce the use of chemicals. If chemical spraying is chosen, it is necessary to identify clearly the pest and the disease to be able to use the correct and most efficient chemical among those that are officially authorised. A recent on-going project (SUSPER: Sustainable Development of Periurban Agriculture in South-East Asia) has proposed the development of a physical barrier method. To protect the leafy vegetable crops, mainly crucifer, from insect attacks, farmers are advised to place tunnels of nylon nets with 500-micron stitches (or 32 mesh) over the crops. The mesh is small enough to keep out the diamond back moth cabbage worm (Plutella xylostella); a chemical treatment could be applied under the net if needed. For maximum efficiency, the net should not have any holes. To combat the stripe crucifer flea beetle (Phyllotreta striollata), the soil should be flooded 48 hours before sowing in order to kill all the pupae in the soil.

The political authorities are very concerned about the inappropriate use of chemicals. For instance, the Hanoi People's Committee has encouraged the development of a better-quality vegetable industry. One of the most successful initiatives is the setting up of safe vegetable production for specific markets, such as for school canteens, restaurants and high-income consumers. In comparison to the standard production, safe vegetable production is a good opportunity for maintaining vegetable production in the periurban area. Reducing the use of pesticides is a response to the risks of damaging human health and polluting the environment.

Peri-urban production is a successful example of market-oriented agricultural development that emerged after the 1988 and 1993 reforms. With 79 percent of the areas around Hanoi cultivated with rice, horticulture has a number of other functions than bulk food production: providing an income, protection against flooding, supply of fresh leafy vegetables (80 percent of leafy vegetables consumed in Hanoi come from Hanoi Municipality), providing specific vegetable and ornamental crops for processing and for export, maintaining the cultural identity around the villages, and the creation of an open space in a very densely inhabited area (this is of course together with the rice fields).

Case of Horticulture in Dakar, Senegal

Hubert de Bon

Dakar (2 million inhabitants, 550 km²) is located in the far west of Africa and has a subCanarian climate, which is excellent for horticultural crops: an annual rainfall of 300–500 mm during the short wet season from June to October, followed by a dry season from November to May with relatively low temperatures due to the influence of maritime trade winds. In the area called Niayes, a large number of vegetable, flower and fruit crops such as strawberry, cabbage, tomato, lettuce, radish, French beans and Irish potatoes are grown. The large variety of vegetables grown is mainly for the local market but some of it also goes to the European market. The name Niayes is derived from the local word 'niaye' which means a depression between parallel sand dunes. Garden areas range from 1000 to 10,000 m². Horticulture is practised mainly with irrigation during the dry season, but is also rain fed during the wet season.

The traditional irrigation systems in the lowlying areas use water from the water table just below soil level. The soil is very peaty in the lower parts and becomes more sandier up the dune slopes. The fields are watered by hand from tanks twice a day. Manual irrigation demands up to 60 percent of the labour used for production. Sometimes, small electric or fuel pumps are used, which enables increasing the size of the plots. If domestic or urban water is available, vegetable farmers can negotiate a special price with the water companies to use this water for agricultural purposes.

Roof top gardening in Dakar, Senegal

Production during the wet system is limited by different factors. The areas for horticulture shrink because the low-lying areas between the dunes fill up with water during this season. Only a few vegetable varieties are adapted to the high temperature (around 29°C) and high humidity: hybrid tomatoes, eggplant, hot pepper, okra, watermelon, bissap (Roselle) and jaxatu can be grown during this season. Numerous pests and diseases have been identified on the different species: mainly insects (thrips on onion, fruit flies on solanaceous fruits, borers on cabbage, leaf miners on leafy vegetables etc) during the dry season; and fungi and bacteria (Phytophthora rot, bacterial spot on tomato) during the wet season. Throughout the year, everywhere in the sandy soil of Niayes, the root knot nematode (Meloidogyne) causes severe damage to various crops: tomato, lettuce, cucurbits, eggplant, okra etc. Different methods are used to control the development of this nematode: flooding during the hot wet season, using non-host crops such as cereals, and fallowing the land for several months.

In Dakar and in the Niayes area, a main constraint is the scarcity of water. The large size of the city limits the amount of water that can be used for agriculture. It is now forbidden to dig new wells to gain access to the ground water. Most of the horticultural growers complain that the water scarcity limits their production. The growers therefore have to increase the efficiency of water use and improve the profitability of production. There are two ways to deal with the shortage of water: 1) increase the efficiency of the irrigation system and 2) use wastewater. Improved irrigation systems have been developed: drip irrigation, hydroponics with water recycling, sub-irrigation by capillarity. These new systems have been tested by different projects with successful reduction in water use, but very few of these have been adopted by farmers. The use of wastewater seems to be a promising alternative. Wastewater is used after a first treatment in a purification station. An advantage of wastewater is that it contains some of the nutrients required for the growth and development of the plants, mainly nitrogen and phosphorus. This reduces the use of organic and chemical fertilisers on the crops. The risk of plant contamination and transmitting human pathogens can be increased by watering of the crops during cultivation and just before harvesting. Several low-cost systems have been tested in Dakar to improve water quality: waste-stabilisation ponds in the traditional form or with plants such as cattail (Typha) and water lettuce (Pistia). Another solution is not to apply the water directly to the crops but rather to use sub-irrigation and hydroponics. See also chapter 9.

Thus the main problem for sustaining horticultural production in Niayes area is the water requirement of the crops. The competition between agriculture and other urban activities (mainly the development of buildings) is very high. At present, there is still a place and a function for agriculture as long as access to water, whatever its source, is not too expensive, and as long as urban citizens recognise horticulture as a way of managing urban spaces and getting cheaper and fresher food.

Micro-technologies for Congested Urban Centres in Ethiopia

Yilma Getachew

Addis Ababa sustains 2.5 million people on a total area of 50,000 hectares of land, of which the concrete and asphalt build environment takes up around 20,000 hectares. In this congested city, the availability of land for food production is becoming very scarce.

The Government of Ethiopia had begun to promote urban agriculture. It is included in the research agenda of the Ethiopian Agricultural Research Organization (EARO), in the teaching agenda of Addis Ababa University, and in the development agenda of GOs, NGOs and CBOs in Ethiopia.

Organic agriculture emphasises diversity and provides both quantity and quality of food which in turn generates income to purchase other food. Ethiopia is blessed with natural resources conducive to organic food production. Its soils are fertile and living, and its water is hardly polluted by salts and pesticides. There is also an abundance of traditional knowledge.

Bio-intensive gardening is a method that capitalises on the forces of nature in all phases of plant development: growing, fertilisation and pest control. The method has four important components: production techniques; natural fertiliser techniques; natural pest and disease control techniques; and small-scale water harvesting techniques.

Training of trainers in Addis Ababa

Production Techniques

The Biodynamic French Intensive Method

This method, according to Jeavans (1982), is a combination of biodynamic techniques developed in Germany and the French intensive techniques developed in France. The Biodynamic French Intensive method is a form of organic agriculture comprising three basic principles. The first principle is to grow plants so close to each other that when they mature, their leaves just barely touch. This creates a situation in which the microclimate and the living mulch reduce weed growth and conserve moisture. The second principle is the use of raised planting beds (60 cm deep). These plots have loose soil that allows for air, moisture and warmth together with sufficient organic nutrients that help roots to properly penetrate the soil. The third principle is to feed the soil (and not the plant) by using organic fertiliser and natural methods of pest control. In short, the method is less dependent on expensive external inputs, is space intensive, water conserving, depends on family labour only, and creates minimal pest problems. Families practising the method are likely to have well-balanced nutritious food and a better income from products that are grown without risks.

The FAITH garden method

There are numerous organic wastes in our kitchens and gardens that are not recycled to produce more food. Such wastes include: weeds, grass, leaves, kitchen waste (peels, organic refuse, egg shells), livestock manure, ash, hedge clippings, hair trimmings, chewed sugarcane, etc. The FAITH method includes basket gardening that makes use of these wastes to produce food. This technique requires bottomless baskets to be placed on the top of a hole (30 cm diameter × 30 cm depth) dug into the ground. All kitchen and garden waste is dumped into the hole. At the same time, desired vegetables and fruits are planted about 20 cm away from the basket. Through their root systems, the plants extract moisture and nutrients from the fermenting waste. This method produces organic food and fertiliser, conserves water and protects plants.

The Barrel garden

Imagine producing over 25 plants of Swiss chard or strawberries in a space less than one square metre? The materials needed to do this are a 200-litre barrel, a corrugated iron sheet, soil mixture (preferable 2 parts soil to 1 part aged manure or compost and 1 part sand), and manure tea.

Several incisions of about 12 cm each should be made around the barrel. The upper lips of the incisions are hammered inward and the lower lips outwards. The incisions should be made in intervals of 15 cm horizontally and 20 cm vertically. The barrel top is open while the bottom is perforated with about 10 holes. A rolled corrugated iron sheet is placed in the middle of the barrel and filled with sand. The space between the inner wall of the barrel and outer wall of the corrugated iron is filled with the soil mixture described above. Vegetables or fruits of choice are planted in the space between the two lips of the incisions. Regular watering is done through the sand in the middle. Manure tea is applied on a weekly basis through the sand in the middle. The barrel should be maintained over gravel for better aeration and drainage.

The benefits of this technology is that it enables families to increase the availability of micronutrient food and encourages the reuse of old barrels and trashcans (which are freely and cheaply available), the composting of organic solid waste, and using livestock waste as manure tea.

The Trench Garden

The trench garden method is interesting in situations where malnutrition (of macro-nutrients) and excess of livestock manure go hand in hand. The technology requires seed potatoes, aged manure and mulching material. To develop the trench garden, one needs to dig a 30 cm wide, 30 cm deep and 6 meters long trench. At the bottom of the trench, the soil should be cracked to a depth of another 30 cm to allow better aeration and drainage. After planting the seed potatoes at intervals of 30 cm, the trench is completely filled with aged manure in between plants. After two months each potato plant will yield one or two tubers per week, or about 2 kg per week, per trench, for duration of two months. After two months, the trench is refilled as before, which will continue to supply the family with potatoes for another two months. Depending on the availability of garden space the family can build several such trenches..

Trench Garden

Management of Bio-Intensive Gardens

Apart from the production techniques, the bio-intensive garden practitioner needs to fertilise his plots, apply pest control and use water efficiently. Sustaining soil fertility in the natural way is the most important component in the organic farming/gardening strategy. There is a basket of choices of organic fertilisers that can be categorised as manure-based, legume-based or biomass-based. Additives like wood ash, bone meal, egg shells, etc. contribute greatly to organic fertilisation, by producing potash, phosphorus, calcium and iron if the soil micro-organisms are allowed to work on them.

There are three approaches to keeping pests and diseases at bay, the natural way. The first step is to have strong healthy plants growing in healthy living soil so that they can build resistance. The second is to fight harmful insects through beneficial insects and animals such as ladybirds, praying mantises, wasps, lizards, birds, etc. The third is to apply natural pesticides such as pepper, tobacco, pyrethrum, stinging nettle, etc.

Three major categories of activities aimed at the efficient use of water can be mentioned. The first is harvesting water during the season of plenty, for use when there is less water - roof water harvesting, ponds and artificial lakes are some examples. The second is to conserve the available water by mulching, shading, precision planting, etc. The third is recycling water or reusing it for a second and third time depending on the previous use.

Promoting Bio-Intensive Gardening in Ethiopia

Relying on the natural resource base, simplicity, affordability and productivity are the features on which training on these techniques is designed to respond towards greater sustainability, replicability and equity. To date, 800 families have participated directly in the training programmes on bio-intensive gardening in Ethiopia. Replication of the technologies amongst the communities is reported to have reached 8,000 families. The trainees are a mix of male, female, urban and rural dwellers. A typical module for a demonstration training plot is about 70 m².

Opportunities and constraints in Ethiopia

Illegal land occupation, use of contaminated downstream city rivers and the absence of urban agriculture in city planning are forces that have discouraged this approach in Ethiopia. However, through years of campaigning by environmentalists and agriculturalists, urban agriculture is now recognised by policy-makers and has been included in the master plan for more than four cities and towns, with others to follow.
The market is a real problem in the Ethiopian rural setting as far as vegetables and fruits are concerned. Traditional diets being predominantly cereal-based and fruits and vegetables being perishable are the main reasons. The overall poverty situation contributes to poor consumption and production of food rich in micronutrients.

Training in the bio-intensive approach to urban agriculture began in Ethiopia ten years ago. Since then, training sessions have included youth clubs, women's clubs, pensioners' associations, extension agents, farmers, school teachers and students, NGO workers, etc. In all these cases, the training sessions had limited hands-on practical sessions due to a lack of permanent demonstration plots. Thus the need for establishing a school of urban agriculture has surfaced, and is supported by several NGOs and governmental offices.

Recommendations

Urban agriculture is accepted as a policy by the Addis Ababa city administration and the city planning has set aside land for the purpose. What is not well understood by the authorities, however, is the potential of the organic option to urban agriculture and the available technologies. Seminars, workshops and publications need to address this issue. The poverty eradication strategy of the country needs to include urban agriculture as one among the important tools in the fight against poverty in urban areas.

References

CSA. 2001. Central Statistical Authority of Ethiopia.

Jeavans J. 1982. How to grow more vegetables. Berkley, California: Ten speed press.

Yilma G. 1996. The FAITH Garden Module - The Urban farmers series. Addis Ababa, Ethiopia: Graphics.

Yilma G. 2001. The living garden: a bio-intensive approach to urban agriculture. (Unpublished).

Yilma G. 2001. The organic option to food production in Ethiopia: a blessing or a curse. Addis Ababa, Ethiopia: The Daily Monitor.

Vegetable production in Yaoundé, Cameroon

L. Temple
Lekane Kembou Hubert
O. David
Isaac R. Tchouamo

Yaoundé, the capital city of Cameroon, has around 1.5 million inhabitants with a population density of 5691 persons/km². Situated at an altitude of between 700 to 1200m, 60 percent of the administrative area of Mfoundi is devoted to agriculture. This choice is reinforced by the geography of the land: swampy and flooded lowlands, hills and steep slopes. In the equatorial climate of South Cameroon with four seasons (1600 mm annual rainfall), peri-urban production has the advantage of providing a regular year-round supply of fresh and perishable products, independent of the condition of the roads. The horticultural sector includes fruit-tree nurseries and orchards, ornamental plant production, vegetables and staple foods. Peri-urban production takes place within the administrative borders of Yaoundé municipality at a distance of less than 50 km from the city centre. It develops steadily following the axes of urban development (roads, rivers and canals) in the numerous lowland areas where water is easily available and no building is permitted. Agronomic conditions in the lowland areas favour vegetable production. In total, there are 14 streams that could be sources of water for horticulture within the municipality.

According to a survey carried out in 2002, most of the periurban farming households (71 percent) have a second, non-agricultural source of income. More than 60 percent of the farmers are women. The non-agricultural income is derived by an occasional job (worker, joiner, bricklayer etc) or a permanent job (employee or civil servant). Only in 20 percent of the cases did the non-agricultural income predominate in this type of periurban agricultural household. On the other hand, farms larger than 5 ha require full-time workers to maintain operations. The average acreage of farms is 0.49 ha. More than half of the farms use external supplies of organic matter. Around 40 percent of the farmers also keep livestock (poultry, pigs, goats, or fish).

The two main vegetable-growing systems are the lowland system and the upland (or plateau) system. Various vegetables are grown: the "fruit" types such as tomato, chilli pepper, sweet pepper, okra and eggplant; the large leafy types such as leeks, lettuce; the more African-type vegetables; and the aromatic types such as basil, parsley, celery, mint, black nightshade, amaranth and jute mallow. Tomato and chilli pepper are more frequently grown in the uplands; leafy vegetables are the most common in the lowlands. Pests and diseases of vegetables are major constraints, mainly in the case of leafy vegetables of indigenous and exotic species, for instance, septoria spot and fusarium rot on celery, septoria spot and nematode on parsley, and damping-off and leaf miners on jute mallow. Insecticides and fungicides are very often used to protect vegetable crops.

In the plateau system, the cultivated crops are mainly staple foods (eg. yam, tannia, plantains and banana, maize, cassava etc) and fruit trees. Around one third of the upland farmers also grow some vegetables. One third of the farmers grow only African-type vegetables, while 10 percent are specialised in European-type vegetables such as tomato, eggplant and leek. The vegetable producers are located mainly in the lowlands and on the lower parts of the slopes.

Peri-urban horticulture in Yaoundé has different functions: i) supply of the local markets as well as home consumption, ii) land development, iii) employment and income generation for vulnerable people, and iv) use of urban animal and plant wastes as well as city waste. Integration of horticulture, livestock rearing and agro-industries is favoured by their geographical proximity within the peri-urban area as well as the proximity between research institutions, development agencies and farmers. Integration decreases the costs that local councils, industries or farms would make for recycling organic matter. It reduces costs to be made by the horticultural producers and contributes to the sustainability of periurban horticultural production. Recycling waste could be a way to maintain and develop horticulture in and around the city in the future.

Resources

Agroecological Innovations
Norman Uphoff (ed.). 2001. London (UK): Earthscan. 328 pages. ISBN: 1 85383 857 8 (paperback); 1 85383 856 X (hardback).
This volume presents both key concepts and operational means for reorienting agricultural efforts towards more environmentally friendly and socially desirable path approaches to the pressing problem of food security. It is a vitally important guide and resource for professionals and policymakers involved in agriculture and food production. Website: www.earthscan.co.uk

The Origins of the Organic Movement
Philip Conford. 2002. Edinburgh (Scotland, UK): Floris Books. 287 pages. ISBN 0-86315-336-4.
Organic production receives increasing attention from governments, scientists, retailers and producers. This book gives detailed explanations about the basic principles of the organic concept, and presents the most important dimensions of organic food production. It is interesting for reasons of history, state-of-theart or simply to gain a better understanding of the subject.

World Markets for Organic Fruit and Vegetables. Opportunities for Developing Countries in the Production and Export of Organic Horticultural Products.
FAO/ITC/CTA. 2001. 317 pp. CTA number 1055.
This is a comprehensive guide that explains almost all that an interested trader, exporter or producer needs to know: What are the requirements for producing and exporting organic products to major markets? What are the characteristics of the individual markets of countries in the EU, in the USA or Japan? Who certifies what, which labels mean what, what is local competition? This publication is based on a study commissioned by FAO, CTA and the International Trade Centre (comprising UNCTAD and WTO). It contains a significant amount of useful facts (by CTA).

Home Hydroponic Gardens and Simplified Hydroponics (Hidroponia Simplificada).
2000 (Spanish Translation 2002) P Bradley & C Marulanda. Global Hydroponic Network. 2000.240 pp GHN, PO Box 15, Corvallis, Oregon 97339, USA,
Hydroponics reduces land requirements for crops by 75% or more, and water use by 90%. Simplified hydroponics is a vegetable production method that utilises modern-day hydroponic technology adapted for areas with limited resources. The technology is explained in this book, accompanied by careful and detailed texts and superb step-by-step coloured illustrations. It gives methods and construction techniques for building hydroponic gardens on waste lots in towns, in backyards, on rooftops, with experiences from Zimbabwe, Senegal and Colombia.

www.cirad.fr/en/pg_recherche

The site of the French organisation CIRAD contains a wealth of information on fruits and horticultural crops, and provides and links to projects and other institutions.

www.puvep.com
This is the site of the PUVeP (Urban and Periurban Small and Medium-Sized Enterprise Development for Sustainable Vegetable Production and Marketing Systems) on periurban vegetable production, consumption and marketing in Cagayan de Oro (Philippines), Ho Chi Minh City (Vietnam) and Vientiane (Laos).

www.avrdc.org
The World Vegetable Center provides documentation and seeds in order to improve production and consumption of vegetables.

www.carbon.org
This is the website of the Institute of simplified hydroponics, which links several projects and presents detailed techniques and examples of applications.

www.uwex.edu/ces/wihort
This site of the University of Wisconsin-Extension is a very complete source of information on gardening and horticulture.

www.reddehuertas.com.ar
The Network on Gardens in Argentina "Red de Huertas" (in Spanish) produces an electronic bulletin "INFOHUERTAS" aimed at linking community development and organic gardening. It is a meeting place of many different gardeners, and it is linked to the national programme: ProHuerta.

www.hydroponictech.com/
Hydroponic Tech is a site is for those who want to grow hydroponically but have found the cost of commercially available hydroponic equipment prohibitive.

www.permacultureactivist.net
The Permaculture Activist is a North American periodical. The website includes general information on permaculture; e.g., a list of sites on permaculture technologies, and a virtual library on permaculture.

Livestock keeping in and around cities is a practice that can be traced back to ancient times. The functions and forms of urban livestock have changed over time, and after decades of neglect, the roles of urban livestock are now being recognised again by urban officials. This chapter reviews the categorisations, relevance and logic of urban livestock keeping in past and modern society. It stresses that animals can be both a nuisance and a benefit, serving several direct and indirect functions in urban ecosystems, each with different priorities at household, city and national level.

'For want of a nail the war was lost...'
ancient story

'The city requires an awful lot of countryside to be able to breathe'
Geert Mak

Livestock keeping in urbanised areas, does history repeat itself?

Hans Schiere
Eric Thys
Francine Matthys

Barbara Rischkowsky
Jaap Schiere

Introduction

Livestock keeping has been and is important in and around ancient and modern cities (Waters Bayer, 1996; Schiere, 2001). It is but one form of urban agriculture, and it often occurs in integration with others such as urban horticulture. Animals were kept in biblical towns, in ancient and medieval cities of Europe, and in Mayan as well as Chinese civilisations. Horse-, camel- and/or bullock carts carried - and continue to carry - goods and armies. Many 'modern' cities still have 'cow-streets' and 'hay-markets' as remnants from times when livestock was part and parcel of urban life. Just 100 years ago, the city of Copenhagen fed cows with the 'wastes' of beer production, and rabbits thrived on London balconies in World War II whilst sheep "mowed" the lawns of Capitol Hill. Even today, slum dwellers get extra cash from backyard chickens, the urban elite keep pets, and urban livestock actually helps to remove organic wastes while being blamed for causing pollution. Strangely, the Victorian English were glad to see horses being replaced by cars because that would reduce the pollution (=horse dung). No doubt livestock keeping in urban conditions has its drawbacks, from being noisy and smelly, to causing serious pandemics such as SARS and illnesses such as tapeworm infections.

Urban livestock is now being (re)discovered by officials, research and development workers, but it exists regardless of official recognition. In many countries livestock or urban farming is an activity that does not have an official status. For example, officials of Mexico City denied the presence of pigs on roofs of apartment buildings until they found animals walking in the rubble in the aftermath of an earthquake that destroyed the buildings in the early eighties. When there is lack of official acknowledgement, research-, policy-and development agencies can neither address the risks, nor use the potential benefits of animal keeping in and around cities (box 12.1). In fact, livestock is often banned in countries where poor people depend on it for their livelihood. But also in wealthier places like Singapore, nuisance and pollution have been reasons for doing away with most forms of livestock keeping. Often, such bans are a reflection of a narrow view on the multiple functions of livestock.

Livestock is part of daily life in Dar Es Salaam

This chapter reviews the categorisations, importance, opportunities and threats of urban livestock keeping around the world. In doing so, we support a livelihoods approach which stresses that a singular focus on food and/or income generation cannot do justice to the many functions of animals in society (Thys et al., 2006; or see the case of Sweden). The direct roles of livestock may be small but the indirect roles can be crucial, in socio-cultural and biophysical aspects. Livestock keeping may fulfil crucial roles (see table 12.2), whether they can be quantified (income or physical health) or not (social networks and mental wellbeing). In addition to the livelihoods analysis, we stress the need for non-linear thinking that focuses on variation and similarity, as well as on inherent logic and necessity of urban livestock systems (Schiere, 2001). This chapter reviews short- and long-term action regarding livelihoods, public health, poverty reduction, CO₂ emissions and biodiversity. It also emphasises the need to address future priorities, and attempts to raise issues for discussion rather than to only settle disputes.

Importance and Categories of Urban Livestock Systems

The role of urban livestock is now recognised in many poor and wealthy countries. Although Box 12.2 and table 1 provide statistics that confirm the importance of urban livestock, there is more to it than data alone. Poor people tend to keep animals to cope with poverty, while wealthier sections of society justify the need for urban livestock to keep pets, and/or to secure a steady supply of animal produce. The functions and forms of urban livestock keeping vary, but we stress the need to look at variation and similarity. Variation is change (=development) in the forms and functions of urban livestock, as well as the recurrence of basic forms. In capturing this variation, we loosely characterise rather than strictly define urban livestock systems:

Urban livestock systems occur in a large variation of forms and functions, in and around densely populated areas, and they strongly interact with surrounding communities, poor as well as wealthy, at several levels of system hierarchy, as well as with rural areas.

This characterisation complements the one on urban areas by UNDP (1996):

Urban encompasses the entire area in which a city's sphere of influence (social, ecological and economical), comes to bear daily and directly on the population.

Characterisation instead of definition reflects non-linear system thinking. It prefers to use surprise and change rather than average solutions and standard approaches. For example, in non-linear thinking livestock can be a labour opportunity for poor people, rather than being a problem in terms of labour demand for wealthier groups; animal excreta can be a resource rather than a waste; and animals can help to clean the city by removing garbage rather than cause disease by producing garbage. Strict definition cannot do justice to the variation of systems - keeping of pets by urban elite, to industrial poultry keeping to goats in slums. Use of variation helps to see patterns that repeat themselves, which can be a basis to design classifications for useful discussion (Schiere, 2001; or see the case of Addis Ababa).

Some classifications use the difference between city-types, eg. between inner city and the outskirts, depending also on whether one considers relatively open or dense cities. It is indeed quite common to distinguish "rings", eg. urban (inner city), urbanising (fringe), and more rural systems. Such rings as in figure 12.1 are useful notions, but they are neither static nor isolated from each other. They also occur at different levels within and between neighbourhoods. For example, a poor lady keeping backyard chickens may live next door to a wealthy merchant in an affluent area, wealthy people produce left overs in urban restaurants that help poor farmers keep animals, and a small city may actually be part of a larger one. Less common distinctions are based on scale and the use of fossil fuel energy (table 12.2 and figure 12.1). They relate to issues such as community resilience, resource flows, social structure or CO₂ emissions. The recent outbreaks of SARS and avian influenza may require distinctions based on health risks, eg. by being especially alert for systems where waterfowl and people interact closely.

Table 12.1 Annual per capita consumption of livestock products in Beijing

Based on Bingsheng, 1998.

In Figure 12.1.a and b, the scale, system structure and aspects of (social) control in different urban livestock systems is presented. It aims to show variation and similarity, as well as different magnitudes of resource flows and cycles. The concentric circles in both graphs represent resp. inner city, urbanising area, peri-urban regions and the rural districts. Small scale livestock keeping (left side of the two semi-circles) tends to use small animals and small enterprises, as well as local recycling and -thus- little waste as represented by the small semi-cycles with arrow. In this case some young stock and feed is imported from the rural regions, but animal keeping takes place mostly at local level (within-city). The large-scale enterprises (right hand circles) tend to use larger animals and/or larger production units. Feed, young stock and even skills, medicine and fossil fuels are largely imported from the countryside in case of bulky roughage for ruminants, and from external sources in the case of more sophisticated feedstuff. Leftovers from large-scale agro-industry are processed. The inflow of resources from bottom and top right can be considered as part of a cycle, if waste is not disposed of into canals and drains. In all cases the resource flows of the larger animals and enterprises are of a larger magnitude than those of smaller animals/enterprises, generally requiring more prime quality feed and (fossil) energy for transport. They, therefore tend to be under control of larger businesses than the livestock systems with smaller scales and cycles as depicted in the picture on the left. These sketches are based on personal observation and generalisation.

Figure 12.1 a and b System structure and aspects of control in different urban livestock systems

Table 12.2 Categorisations of urban livestock systems

Based on UNDP, 1996; Waters Bayer, 1996; Schiere, 2001.

Note: dotted lines indicate that more patterns exist than shown here. Columns are divided by double lines since they are independent listings.

Table 12.3 Issues of scale and energy use

In this table approximations are used based on common sense and are meant to stimulate rather than to freeze discussion.

Note 1: exception proves the rule; rabbits etc. can also be kept on the balcony as pets by wealthy urbanites.

Note 2: question marks imply uncertainty regarding this aspect due to local differences.

Logic and Advantages of Urban Livestock Systems

The fact that urban livestock continues to be found around the globe implies advantages for local "stakeholders" to embark on some form of urban livestock keeping. These advantages could be in one or more of factors such as food supply, income, emotion, tradition, savings, ecological functions (like scavenging) and social coherence, in spite of the nuisance of a noisy goat or a smelly pig. Singling out of one of these factors would most likely miss out the essence of urban livestock keeping and agriculture in general; but simple calculations may illustrate processes that repeatedly lead to similarities and differences of such systems. For example, a simple calculation during a lunch break in Nakuru (some 150 km. west of Nairobi) helped explain changing functions and forms of livestock keeping when approaching the city (table 12.4). This common sense reasoning in 1997 strongly resembles the 'rings' found by the German economist Von Thünen some 150 years ago. Such calculations show how forms and functions of livestock systems change based on environmental pressure and/or socio-cultural attitudes. They also illustrate system dynamics and often unnoticed movements of resources and animals from rural to (peri)-urban areas for fattening or milking, now referred to as urban-rural linkages. Flows of young animals to the city as illustrated in figure 12.1 are often accompanied - in the case of dairy- with a reverse flow of dry and barren animals that recover on the range and are brought back to the city again for higher yields with higher density feed. These are given the term "flying herds" in urban livestock jargon. Milk is a valuable product in the city, where it can be too expensive to rear young animals. But milk in distant regions cannot be sold well where it makes more sense to raise animals. And feeds fetch higher prices when fed to animals in cities than in rural areas. Similar reasons explain why large-scale hatcheries are established in the countryside, while the actual production of eggs takes place in peri-urban regions. Factors such as climate, disease pressure, local politics and labour costs may complicate these processes but not the general patterns. In short, urban animal keeping has its advantages and disadvantages, like everything else in real life (table 12.5).

In fact, it is particularly the larger urban livestock systems that are linked to the rural areas and other urban systems, through exchange of inputs of feed, animals, labour, and outputs of cash for extended families in the rural areas or manure for vegetable farming (see figure 12.1). The resource flows from city to rural areas and vice versa are seen in West Africa where a part of Fulani families settle in the cities and keep high milking cows to sell the milk, while the main part of the herd is kept by other family members under pastoral production conditions. Dairy farmers in the Pakistani Punjab buy the best cows in rural areas soon after calving and keep them in cities to get high prices for the buffalo milk on the urban market (Seré and Neidhardt, 1994). Traders of forage in Maroua/Cameroon tend to be farmers from the surrounding rural areas at a maximum distance of 40 km. In other words, the logic of urban livestock keeping is based on the positive roles of livestock in urban and rural areas.

Table 12.4 Forms, functions, interrelationships and problems in dairy production systems

This table is based on a case from Nakuru (Kenya; prices in KSh/kg). The assumption is that 1 kg concentrate feed yields 1.5 kg of milk. In the first column (close to city) it makes sense to feed concentrates for milk, while it makes no sense to do so in areas far from the city. The row "milk market" comes from data collected at Pondicherry (India), as are the prices and yields between brackets (Ramkumar, pers. comm., 2004)

Table 12.5 Potentially positive and/or negative aspects of animal keeping.

The list does not give absolute "values", it leaves final value-judgements on positive / negative aspects to local context and stakeholders' opinions, and in that sense some issues occur in both the left and right hand column.

Figure 12.2 Movement of sheep from the countryside to Dakar (Senegal)

This is from low to high energy density feed areas, and from producer to consumer (Diaw et al., 1999)

Disadvantages of Urban Livestock

Urban livestock keeping has its advantages, but also its disadvantages. Non-linear system thinking and common sense accept such trade-offs as a fact of life. But mainstream thinking tends to exclude livestock from cities almost across the board, e.g. due to notions of backwardness and risks associated with keeping livestock such as disease and nuisance. A complicating matter is that (in non-linear thinking) a disadvantage in one place can be an advantage elsewhere or for someone else. And indeed urban livestock does have its drawbacks, perhaps more than urban horticulture (see chapter 11). Some disadvantages threaten the general public, e.g. in the case of SARS and avian influenza. Others are just a nuisance, as is the noise of a goat (in spite of so many other noises in the city), smell, dust, flies (what about rats appearing if garbage is left uneaten by livestock), damage to gardens (ignore damage by cars or house builders to trees and plants), or a notion of backwardness implied in urban livestock keeping (wealthy people like to show off with horses or exotic birds) Table 12.5 lists advantages and disadvantages, which depend on stakeholders' priorities and conditions.

Following up on the earlier categorisations and rings of urban systems it is safe to say that problems of urban livestock increase with high concentrations of animals and people, particularly in unhygienic urban environments. Animals near homes and workplaces may be a nuisance to neighbours (odour, noise), clog sewage systems, cause traffic problems and/or contaminate water sources (UNDP, 1996). Pollution can be high in systems based on imported feed (the rich systems), not in the "poor" systems where animals serve to clean the environment by scavenging and eating leftovers. Animals may also cause disease and in-equality by increasing the workload of women and children, while at the same time contributing to their independence and health by providing essential nutrients or savings. Such contradictions are the core of what we call a "surprise" in non-linear system thinking and form the basis on which we stress the need for tailor-made solutions and useful categorisations. Participatory technology development gains favour around the world because it helps find local solutions for local problems, also in urban livestock keeping. And last but not least, it is the disadvantages that harbour opportunities, if properly addressed.

Sheep roaming free in the city, Sweden

Critical Issues and Opportunities for Short and Long Term

Much is now documented on technical and socio-cultural aspects of urban farming and livestock keeping and major issues are summarized in table 12.6. Issues of short term-, farm-and society-level actions are covered in journals and books, in the other cases of this section, in the RUAF journal, in Schiere & Van Der Hoek (2001) and in handbooks and practical literature on backyard animals. Many practical cases of urban livestock are also known, e.g. as described for poultry and dairy in Eastern Africa by Sumberg (1998/1999) or by Tegegne (see the case on Addis Ababa), or on small ruminants in the USA (see box 12.3 by Bellows, et al,. 2000).

We therefore chose to address issues other than dung disposal or hygienic food preparation when discussing the future of urban livestock keeping. These 'other' issues are not more important than farm-level work, but they tend to get lost in the rush of the day and short-term solutions. And they do need policy back up, whether in poor or wealthy countries. By and large they are:

• global concerns regarding food security, poverty, energy use, CO₂ and biodiversity
   
• public health hazards from SARS to parasite infections and hidden issues of community 'health' like social cohesion and resilience.
   
• the need for flexible public administration and the notion of tailor-made solutions

The challenge is to provide new vistas for work with urban livestock, and one should not justify urban livestock because one happens to like it, or because it happens to exist. The future of good urban livestock keeping practices lies in the analysis of how and why it occurs, and on how or why it could be of use in the future. Some arguments overlap with those for urban agriculture in general, but livestock has its own issues such as dung and noise over pesticides and herbicides, or avian influenza over weeding and pruning.

Food security and poverty, energy and CO₂, biodiversity and scale

Work on urban livestock can be justified or criticised on many grounds, but an important set of arguments, concerns and obligations are contained in the international conventions such as Rio (biodiversity), Kyoto (on CO2) and Johannesburg (food security and poverty alleviation). Put together, these obligations are painful, contradictory and inherently hard or impossible to fulfil. For example, how can the need for lowering CO₂ emissions be reconciled with the political urgency of creating jobs and increasing consumer spending? And how can notions to stimulate industrial animal production to supply increasingly wealthy urban consumers with animal proteins be reconciled with the approach of poor urban producers to consider animals as scavengers. Much of what follows in this chapter focuses on the keeping of livestock by the poorer sections of people in urban areas, focusing on small-scale systems with mostly small animals in slums and backyards, in balconies and on rooftops, as well as on larger animals in peri urban regions. Industrial systems require their own approach, but that discussion is beyond this chapter, in spite of the useful lessons that different systems can learn from each other, eg. regarding notions of multi-functionality (livelihood-analysis!), small-scale gardening or recycling, and re-establishing links between consumers and the countryside.

The above mentioned international conventions offer good arguments, particularly for keeping of smaller animals and related enterprises, for example:

• food security is served both by the actual supplies of nutrients and income, as stressed by the use of livelihood approaches. A focus on food-output by industrial systems overlooks significant roles of small urban livestock in terms of scavenging, and of producing local food where needed and affordable, thus supporting community resilience
   
• small and diverse animal production systems fit well in notions to enhance local (bio)-diversity. If well done, small scale urban agriculture can be a seedbed of diversity, in terms of ingenuity as well as resilience. The associated notion of "requisite variety" as it is called in academic terms, implies that systems need a variation of organisms [and sectors] to clean its waste, thus potentially increasing local hygiene.
   
• small scales tend to depend less on fossil energy than larger scales, eg. by requiring less transport, refrigeration and packaging, and may also better use local leftovers,. One study of food systems in the UK showed that a meal from imported ingredients generates nearly 650 times the transport and related CO₂ emissions than when made from the same but locally-grown ingredients (Halweil, 2002).

Table 12.6 Areas for further work on a rather short-term and local scale

Note: prepared during a workshop on urban livestock in West Africa (ITC, The Gambia) in January 2005. They are mainly technical. The sub-topics were listed by participants, and clustered by Okike and Kofi.

Studies on the value of urban livestock for food alone is of little value or even misleading, as are more detailed studies on purely the numerical importance of livestock without speciation of categories, relations and multifunctionality. Studying the roles of livestock with livelihoods analysis can provide new clues for planners and policy makers. Work on issues like feeding of particular by-products is likely to be "more of the same" and is probably better done [in cooperation] with 'farmers' themselves who are the best location-specific experts. The future of urban livestock keeping depends on a better understanding of underlying issues such as food security, poverty alleviation, resource use efficiency, and trade-offs between these.

Public health and emerging zoonotic diseases

Disease risks of urban livestock systems are likely to need much more attention in the near future. This should, however, be a reorientation towards a more holistic focus on social issues and system specificity, moving away from a single focus on disease as a clinical issue. Recent cases of SARS and avian influenza in densely populated areas of Asia have made zoonoses a major concern in public health (Aldhous, 2005). Indeed, the combination of high densities of people and animals in the same location can increase the risk of disease, but is not true that industrial animal production necessarily increases these risks. Poor hygiene and a lot of direct contact between people and animals can have the same high risks. Disease is transmitted from animals to people in many ways, by direct contact and also through consumption of animal products. Some of this can also lead to epidemics and transmission from humans to humans, eg. in the case of yellow fever (Van Der Stuyft et al., 1999). Human health inextricably links to animal health and production, where animals play an important cultural and socio-economic role (WHO, 1999). Urbanisation causes changes in behaviour of humans in food purchases or contact with animals and pets and increases risks for spread of zoonotic diseases in poor hygienic conditions.

Zoonoses can be distinguished into viral (rabies, SARS, avian influenza), bacterial (eg. tuberculosis, brucellosis) and parasitic (e.g. cysticercosis and tapeworms) forms. Some viral forms, eg. rabies and avian influenza, are the result of direct contact between animals and humans. But others zoonoses such as yellow fever, plague or trypanosomiasis have animal carriers and are transmitted from animals to humans by mosquitoes, fleas and/or flies. Parasitic diseases could be tapeworm related as in hydatidosis and human neuro-cysticercosis (Van t'Hooft, 2000). Brucellosis and tuberculosis are linked to increased dairy production in the urban and peri-urban context, inadequate milk processing and uncontrolled market chains (Muchaal, 2001). Recently, Traoré et al. (2004) reported 13 percent brucellosis and 28 percent tuberculosis among intra-urban dairy cattle in Ouagadougou (Burkina Faso), but little is known on numbers of human cases of tuberculosis caused by Mycobacterium bovis. Also, tuberculosis is an opportunistic infection in HIV+ persons in sub-Saharan Africa. M. bovis may also become opportunistic in HIV infected populations, as happens with zoonoses such as listeriosis.

Food-borne zoonotic diseases also become more important due to a higher demand for meat by a growing urban population. Poor slaughter hygiene can lead to contamination of carcasses, and larger scales can increase risks of mass-transmission diseases. Drinking water and vegetables contaminated with slaughterhouse wastewater can transmit pathogenic agents such as Salmonella sp., Campylobacter sp., and Escherichia coli producing toxins (Pal et al., 1999). Food that is poorly preserved in refrigerators due to frequent power cuts may amplify the problem of food contamination. These diseases, with the exception of toxin poisoning, can be transmitted from person to person, but little is known on the importance of these diseases. For example, diarrhoea is frequent and therefore considered rather banal in many countries, i.e., the causes are rarely investigated. In the early stages of the production process, contamination of feed with infected faeces (eg. Salmonella) can lead to infection in animals. Animal products can further contain residues of antibiotics or pesticides, and allergens from livestock waste or dust can cause occupational diseases in farm workers and proximity diseases in neighbours (McBride, 1998).

Guinea Pig (Cuy) breeding in Lima, Peru. The materials needed are cheap and locally available.

The growing trend of health problems relates in part to the inadequacy and deterioration of public health and veterinary infrastructure in poor countries (WHO, 1999). For example, Coulibaly and Yameogo (2000) reported a lack of collaboration between public health and animal production services in controlling zoonosis in Burkina Faso. Currently veterinary services in many cities of developing countries seem more concerned by rabies and eradication of stray dogs (Meslin et al., 1996). On the other hand, the prohibitive costs of private or state veterinary services make smallholders reluctant to ask for help, and more so because they tend to be part of an informal or even clandestine sector. In addition, there are often no adequate testing facilities, farmers can easily evade the public health systems and many are unaware of the public health risks associated with keeping of animals in proximity to human populations (UNDP, 1996; Guendel, 2002).

Traditional Cisticercosis control at a weekly market in Bolivia

In spite of all this, not much research has been up to now in comparing the specific risks of urban to rural livestock keeping. Real risks do exist, depending on the location (rural, peri-urban, inner city), the kind of livestock and the way they are kept. A survey among African experts from 27 West and Central African cities showed that only 43 percent of them had heard of diseases transmitted to humans from animals in urban contexts, but not all these cases were confirmed (Thys & Geerts, 2002). Protective frameworks are required to deal with the upward trends in disease occurrence due to increasing population pressure and densities and the multidimensionality of health. Intensification of animal production in and around cities combined with changing food habits make food safety a priority issue. Climate change coupled with increased population density can favour the further spread of vectors and diseases (Wittmann & Baylis, 2000; Ungchusak, 2005; Aldhous, 2005). In this context, there is a grave risk in paying too much attention to politically-sensitive diseases as SARS that divert interest away from more fatal disorders. Municipal, veterinary and public health services should work together and search for newer approaches because of the relations between human and animal health, and the socio-economic importance of animal production especially for the poorer people in the city.

Public administration and policy

The final 'higher-level issue' addressed in this chapter is the thinking about public policy, and the need for paradigm shifts. Steps are needed to move away from thinking in standard/linear solutions to one aspect (eg. to cure disease) toward approaches that consider combinations of factors (disease, population density, community organisation), multiple functions as stressed in livelihoods analysis, differences between communities, and surprise and tension due to different perceptions in participatory approaches. A few of the points that could be considered are that:

• it may be better to accept and regulate (in a non-linear way), than to ignore a sector that clearly fulfils a need of urban inhabitants. An example could be the provision of official status for selected forms of urban livestock keeping, particularly in urban zones where it is now illegal (see box 12.4). Possible systems are (cleanly kept) small animals such as rabbits, guinea pigs and small fowl on balconies and goats, sheep or even larger animals in the peri-urban areas. Waterfowl are a type of animal to be wary of with respect to avian influenza.
   
• educators, administrators and policy makers are key to rediscovering opportunities of urban livestock. Educators can teach hygiene and good forms of urban livestock (Arias, 2002). Administrators may start by considering the differences between regions and the wealth of communities when addressing problems and opportunities. Policies that ban livestock can be enforced in [affluent] places like Singapore but they often promote illegal livestock keeping with associated problems of public health.
   
• innovative and generally participatory work is needed to show impact and sustainability.
   
• creative use of public statistics and record keeping can help to give urban livestock the status that it deserves. Too much focus on numbers can divert attention from the insights into how urban systems evolve.
   
• reassessment of national development plans is required. Many such plans invest public money in cheap feed and tax-holidays for investors and to ensure a supply of cheap animal products, while at the same time causing costs to society in terms of pollution, use of water and oil, and shifting food waste into landfills rather than to be recycled.

Fortunately, there is increasing awareness on the opportunities of urban livestock for poverty alleviation and food production. Several African governments even officially support urban agriculture now, eg. in cities of Mozambique, Zambia and Tanzania.

Reasons for this may be opportunistic, eg. Page (2002) argued that the government of Cameroon started to support urban agriculture as a safety valve for social unrest that was expected after salary cuts were announced for civil servants. Whether due to opportunistic politics or to enlightened individuals, change is possible.

Urban Livestock and the City of the Future, Concluding Comments

The final (and linear) question here is about our vision for the ideal city of the future. But, cities change over time, and perceptions of ideals differ among stakeholders. Most urban livestock keeping occurs in places of poverty, and in unsafe and unhealthy conditions. Livestock keeping in such places is a way to make the best out of the worst, rather than to perfect urban life as a stairway to paradise. In contrast, for the urban elite, the keeping of animals refers to pets, education, feeling good (case Ledin), getting tax benefits or hiding black money. In between these extremes are systems that have evolved out of a demand for fresh products, e.g. the case of milk described in the case on Addis Ababa. The obvious nonlinear answer to the linear question is that there is no such concept as an ideal city or an ideal system of urban livestock keeping. Sketches of an ideal can nevertheless be useful, depending on the present and the thinking for the future. Such sketches include visions that consider cities as potential gardens and Utopia (box 12.5), or have utilitarian notions as found with Le Corbusier, i.e. considering cities as a good place for cheap labour to serve the economy, a step toward Utopia but at a different level.

Possible forms of future cities are suggested in the boxes, cases and literature of this section. Our 'ideal' would be a city (as a first Utopia) that is open-spaced, cooled by plants and shaded by constructions. Such a city should encourage citizens to experiment on small scale, exercising local control on major problems. Smaller livestock could play a good role in such systems. We know this will be hard to achieve, but one could, still aim for a city to incorporate aspects of urban agriculture where specific forms of livestock serve the combined roles of scavenger, pet, savings account, social activator, source of ingenuity and buffer, to name a few. Common sense can help to paint the outline, but more study is required to effectively address issues such as those raised in the global forums of Rio, Johannesburg and Kyoto. Such study should help policymakers to get to grips with ways to facilitate on-the-ground action to obtain more consistent results. Technical aspects of livestock production are sufficiently widespread to get started on the ground and/or to continue what is being done even without official recognition. Most of the issues need to be solved at farm level.

Unfortunately, many "ideal" dreams belong to contexts that are far from ideal, often miserable urban conditions around the world. Urban livestock can provide small but crucial options for the poor, while it is often the wealthy and powerful who manage the large industrial enterprises which have their own problems of pollution and resource use. Livestock keeping by the poor is likely to continue in crevices, with animals being fed on what is leftover. At the same time and as is typical of non-linearity, it might be a crucial weakness and strength of urban livestock to function as a scavenger while providing food and livelihoods for the poor and the wealthy. A main weakness and strength in this respect is the multi-functionality of – scavenging- animals that cannot produce enough food for entire urban populations, but that serve more than one goal at one time. These functions are hard to administer by conventional thinking in public sectors, but it is there perhaps where programmes for urban livestock keeping need to turn their attention to, and where most gains can be made. Even rich societies might re-discover the benefits such as education or local employment, to re-establish links between consumers and producers, short cycles for energy and resource saving, and flexible rules combined with alertness for critical issues such as SARS or Avian Influenza (see box 12.6)

Keeping of animals has always been part of the city, and a link between the countryside and cities. Its potentials are slowly being rediscovered, while related issues require attention at farm as well as 'higher' levels. Urban livestock keeping is back on political agendas thanks to the efforts of pioneering women and men in slums, offices and the academia who see the advantages of this form of urban agriculture, in spite of inevitable drawbacks.

Acknowledgements

Particular thanks are due to Ramkumar from Pondicherry (India) and Okike from Western Africa for their valuable suggestions and comments to the first draft. Thanks are also due to the main editor (René van Veenhuizen) for his patience and constructive comments.

References

Akinbamijo, O.O., Fall, S.T. and Smit, O.B.,(eds.) 2002. Advances in crop-livestock integration in West African cities. InternationalTrypanotolerance Centre, Banjul, The Gambia; Institut Senegalais de Recherches in Agricoles, Dakar, Senegal; International Development Research Centre, Ottawa, Canada. 213 pp.

Aldhous, P., 2005. War on flu. Nature, 433, p102-104.

Arias, E., 2000. Linking students to urban livestock producers in Mexico City. In: Urban Agricultural Magazine, Vol.1, Nr. 2. RUAF, Leusden, the Netherlands.

Bellows, A.c., Robinson, V., Guthrie, J., Meyer, T., Peric, N and Hamm, M.W. (2000) Urban livestock agriculture in the state of New Jersey, USA. Urban Agriculture Magazine, 1,2, October 2000, p8-9.

Benevolo, L., 1983. Die Geschichte der Stadt. Campus Verlag, Frankfurt/Main..

Bingsheng, K., 1998, Area-wide integration of crop and livestock: case study - Beijing. In: Ho, Y.W. and Chan, Y.K. (eds.), 1998. Proc. of the regional workshop on area-wide integration of crop-livestock activities. June 18–20, 1998, Bangkok, Thailand. RAP-publication 1998/19. FAO Regional Office for Asia and the Pacific. Bangkok, Thailand. 86 pp.

Coulibaly N.D. and Yameogo K.R. 2000 Prevalence and control of zoonotic diseases: collaboration between public health workers and veterinarians in Burkina Faso. Acta tropica, 76:53-57.

Diaw, A. Tillard, E., Ly, C. and Foucher, H., 1999. La commercialisation des petits ruminant au Sénégal: le cas de l' axe Nord-Dakar. Pp 181 - 202. Fall, S.T. and Faye, A.(eds). 1999. Production intensive de viande en Africque subsagerrienne. Acte d'un séminair - atelier tenu à Saly Portudal Mbour, Sénégal de 13-17 Marc 1995; Direction des rechreces sur la Santéet les Proctions Animales; Laboratoire National d'elevage et de Recherches Vétérinaires.BP 2057 Dakar-Hann. Sénégal.

Guendel, S., 2002. Peri-urban and urban livestock keeping in East Africa. A coping strategy for the poor ? NR International, UK. 31 pp.

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Meslin, F. X., Cosivi O., Stoehr K., and Mantovini A., 1996. Relevance of Veterinary Public Health in urban areas in the tropics. 7th Symposium on Tropical Animal health and Production. Held on 27 September 1996. Utrecht, Faculty of Veterinary Medicine, p 6-8.

Muchaal, P. 2001. Zoonoses of dairy cattle. Urban Agriculture Magazine 1, 17-19.

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Page, B., 2002. Urban agriculture in Cameroon: an anti-politics machine in the making? Geoforum 33: 41-54.

Pal A., Ghosh S., Ramamurthy T., Yamasaki S., Tsukamoto T., Bhattacharya S.K., Nair G.B. & Takeda Y., 1999. Shiga-toxin producing Escherichia coli from healthy cattle in a semi-urban community in Calcutta, India. Indian Journal of Medical Research, 110, 83-85.

Ramkumar, S., Rao, S.V.N., Garforth, C. and Ganesan, R. 2003. Cattle health information system of the landless cattle owners in the peri urban regions of Pondicherry in Rao, S.V.N, and Ramkumar, S. (eds), 2003. Cattle health issues in the peri-uban regions: potentials of information in coping with poverty. Procs of a workshop held 20-21 March 2003 at Department of Veterinary and Animal husbandry extension. Rajiv Gandhi College of Veterinary and Animal Sciences; Pondicherry-9, India.

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Market-oriented Urban and Peri-Urban Dairy Systems

Azage Tegegne
Yoseph Mekasha
Million Tadesse
Alemu Yami

Urban and peri-urban dairy production systems are among the many forms of dairy production systems in the tropics and sub-tropics. These systems involve the production, processing and marketing of milk and milk products to consumers in urban centres (Rey et al., 1993; Staal and Shapiro, 1996). Urban and peri-urban dairy production systems have evolved in response to the increasing demand for milk in urban centres as a consequence of increasing urbanisation, rising per capita income and increasing costs of imported milk and milk products. They contribute to overall development through income and employment generation, food security, asset accumulation, poverty alleviation and improving human nutrition and health.

The development and sustainability of urban and peri-urban dairy production systems requires a relatively large initial investment and long-term commitment. In addition, the major technical and nontechnical constraints associated with these dairy production systems such as the availability and cost of genetic materials, breeding systems, feed resources, feeding systems, animal health, processing, marketing, public health, waste handling, management, and policy issues need to be addressed. In this case study, the characteristics of the production systems, feed resources and feeding systems, genetic resources and breeding systems in urban and peri-urban dairy production in Ethiopia are assessed.

Small ruminants play an important role in the household economy

A study on market-oriented urban and peri-urban dairy production systems in Addis Ababa was undertaken to characterise general dairy systems and specific sub-systems and to identify major constraints. A total of 147 dairy farms (market-oriented smallholder and commercial) were selected for characterisation, and 49 farms were used for a further detailed study.

Production Systems

Seven, market-oriented, dairy production sub-systems were characterised. The 'milk shed' approach considered systems that supply fluid milk to the city. Both rural and urban systems develop in a dynamic way and shifts between them occur. All these systems are basically market driven due to the large urban demand for milk. In fact they have developed in response to the market demand and have emerged depending on available resources (land, labour, feed, capital, etc).

Traditional crop/livestock farms in rural areas: These farms are located between 25 and 130 km from Addis Ababa, the average distance being 68 km from the capital. They are small farms with an average of four dairy cows, and provide very little or no specialised inputs (new breeds, supplementary feed, housing, veterinary care, etc) to their dairy enterprise. They sell fresh milk on a daily basis to the government-owned Dairy Development Enterprise (DDE). Excess milk is processed into butter and a local cottage cheese (known as Ayib) and sold at local markets.

Intensified dairy/crop livestock farms: These are smallholder farms located around Addis Ababa and exercise some form of intensive dairying. These farms have had experiences with dairy development projects under the Ministry of Agriculture. Projects such as the Selale Dairy Development Project and the Smallholder Dairy Development Project have been operational in these areas and have influenced the production system on these farms. New genotypes, artificial insemination, improved forages, concentrate feeding, housing, calf bucket feeding and early weaning are common practices used by farmers. Compared to the traditional crop/livestock farmers, the land holding in this category is about half the size and milk production is 15 percent higher, but the number of cows per household is similar.

Crop/livestock farms with intensive cropping: These farms are located relatively closer to Addis Ababa city, between 25 and 60 km. The farms and herds are 25 percent larger than those of the traditional crop/livestock farmers. The cropping system is more intensive, particularly in terms of frequent fertiliser use. The animals are given supplementary feeds. Fresh milk is sold to the DDE and they seldom process milk into dairy products.

Specialised dairy farms: These farms are located between 15 and 60 km from Addis Ababa. They are large farms with an average holding of 8.9 ha and 17 cows. They widely use specialised inputs such as new genotypes, artificial insemination, forage production, housing, concentrate feeding, veterinary care, etc. They sell fresh milk in relatively large quantities of over 30 litres per day primarily to local informal markets or to the DDE. Most farm owners have additional off-farm activities that often generate more income than the livestock enterprise.

Peri-urban farms in secondary towns: These farms are located in and around secondary towns within 25 to 50 km from Addis Ababa. Cattle are grazed on own or rented land. Special inputs are linked to the genotype and involve artificial insemination and supplementary feeds in addition to grazing and stall-fed roughage. These farmers, on average, own five dairy cows. The primary outlet for milk is either the DDE or local informal markets.

Intra-urban dairy farms in Addis Ababa: These dairy farms are specialised and intensive production units based on zero grazing of cross-bred and high grade cows. There is little or no grazing within the city and stall-feeding is based on purchased hay and concentrates. The level of exotic blood in the herd is among the highest found in the sample. Annual milk production per cow is high and the milk is directly sold at the local markets.

Urban dairy in secondary towns: These are specialised dairy farms found in most secondary towns within the milk shed. In these small towns, farmers have more access to grazing; stall-feeding is therefore less intensive. The level of exotic blood in the herd is high, but the herd size is the smallest of all the categories and averages about two cows per farm. Milk is sold fresh to local markets or the DDE, or processed into butter and ayib and sold. Most farm owners have off-farm activities representing about two-thirds of their income.

This detailed study conducted on three production sub-systems showed that 76 percent, 22 percent and 54 percent of the farms in secondary towns, peri-urban and intra-urban areas respectively are owned by female farmers. The percentage of illiterate farmers (owners) was highest in intra-urban (50 percent) farms followed by those in secondary town (37.5 percent) and peri-urban (12.5 percent) areas.

Conserved hay, agro-industrial by-products and commercial concentrates are the major feed resources used by urban and peri-urban dairy farmers. Hay makes up almost the entire basal diet of cattle on peri-urban dairy farms. Agro-industrial by-products are fed as supplements to roughage-based diets, and are mainly accessed by peri-urban dairy production systems, due to the fact that most of the by-product processing industries are located around cities and towns where the demand for the major products is high. The use of commercial concentrates is restricted to institutional farms and certain large peri-urban dairy farms. Non-conventional feed resources such husks of pulses and other crops, residues of traditional breweries, poultry waste, vegetable and fruit wastes (Yoseph Mekasha, 1999) are cheaper and play a significant role in peri-urban dairy production systems.

Cross-bred and grade animals are preferred by 85 percent, 67 percent and 44 percent of farmers, while pure temperate breeds are preferred by 10 percent, 33 percent and 56 percent of farmers in secondary towns, peri-urban and urban areas, respectively. Among the temperate dairy breeds, the Friesian is the most preferred. About 92 percent of urban farmers increase their herds through crossbreeding zebu cows with exotic bulls. Purchasing of heifers or cows from other dairy farms is the main source for 29 percent of the farmers in secondary towns and 17 percent in peri-urban areas. The criteria for selection of animals vary. Milk yield potential, reproductive efficiency, disease resistance, breed or size are the most important criteria for bull selection.

Cash income from the sale of milk and/or breeding animals and utilisation of available resources (land, feed, labour, capital) are the most important reasons for keeping dairy animals in urban and peri-urban dairy production systems.

Production, constraints and opportunities for development

Market-oriented urban and peri-urban dairy production systems are emerging as important components of the overall milk production system in Ethiopia. These systems are contributing immensely towards filling the large demand-supply gap for milk and milk products in urban centres, where consumption of milk and milk products is remarkably high.

A survey undertaken by the Addis Ababa Agricultural Bureau shows that there are a total of 5,167 small, medium and large dairy farms in and around Addis Ababa city. The total milk production from these dairy farms amounts to 34,649,450 litres per annum. Of this, 73 percent is sold, 10 percent is left for household consumption, 9.4 percent goes to calves and 7.6 percent is processed mainly into butter and ayib (Azage Tegegne and Alemu Gebrewold, 1998). The total amount of milk available to Addis Ababa is 43,849,675 litres per annum.

A well managed medium sized dairy farm around Addis Ababa

The large demand for milk on the one hand and the small supply of milk and milk products for the major urban centres in Ethiopia on the other hand shows the untapped potential for the development of urban and peri-urban dairy farms. Market-oriented smallholder peri-urban dairy production systems have a tremendous potential for development and could play a significant role in minimising the acute shortage of dairy products in urban centres. Current increases in economic pressure, competition for limited resources and market forces have led to an increase in the level of intensification in these production systems.

In order to sustain high productivity and profitability, high levels of management in appropriate feeding, health care, and reproductive activities are essential. These urban and peri-urban dairy farms are currently facing new challenges associated with intensive production systems. Availability of land, management skills, labour force, feed and water resources and feeding systems, genetic improvement, control of diseases and parasites, udder health and mastitis, calf mortality, reproductive problems, waste management, quality control, public health, processing and marketing and other socio-economic considerations are becoming important factors influencing and determining the survival of these production systems.

References

Azage Tegegne and Alemu Gebrewold, 1998. Prospect for peri-urban dairy development in Ethiopia. Ethiopian Society of Animal Production (ESAP) Publication No. 5. Addis Ababa, Ethiopia.

Rey, B., Thorpe, W., Smith, J., Shapiro, B., Osuji, P., Mullins, G. and Agyemang, K., 1993. Improvement of dairy production to satisfy the growing consumer demand in Sub-saharan Africa: A conceptual framework for research. International Livestock Centre for Africa (ILCA), Addis Ababa, Ethiopia.

Staal, S.J. and Shapiro, B. I., 1996. The economic impacts of public policy on smallholder peri-urban dairy producers in and around Addis Ababa. Ethiopian Society of Animal Production (ESAP) Publication No. 2, Addis Ababa, Ethiopia.

Yoseph Mekasha, 1999. Impact of feed resources on productive and reproductive performance of dairy cows in the Addis Ababa milk shed. MSc thesis. School of Graduate Studies, Alemaya University of Agriculture, Ethiopia.

Grazing Animals as Park Managers? Using animals in the management of urban green areas

Inger Ledin
Anna Jonasson

Interest in using grazing animals in the management of parks and other urban green areas has grown in Sweden in recent years. Through grazing and trampling these animals create the conditions for a rich flora and fauna.

This study was undertaken to document the use of grazing animals for management of urban green areas in Swedish municipalities. A questionnaire with 40 questions concerning the activities, organisation, results, public reactions, among others, was sent to the persons responsible for the management of green areas in 49 (of a total of 290) municipalities that use animals in urban areas.

Common Characteristics of Municipalities

Most of the municipalities were in areas with a vegetation period greater than 190 days and consisted of cities or larger towns. In areas where the vegetation period is shorter, the people will probably be less interested in making all the necessary arrangements to keep grazing animals. The same can also be said of rural communities that have small central urban areas and limited park land and that are moreover surrounded by farms with grazing animals. The grazed areas varied to a great degree but most areas were between 0.3 and 5 ha in size. The primary reason for the activities was a desire to keep the land open, but another important motive was to keep or recreate a certain flora, especially valuable trees.

More than 70% of the municipalities in the study used sheep

Choice of Animal Species

More than 70 percent of the municipalities in the study used sheep. Some municipalities used more than one species on the grazed area, eg. sheep and cattle, which often gives a better grazing result. The choice of animal species and breed depends on the properties of the land that is going to be grazed and the desired grazing result. Since the grazing land is in urban areas it is also necessary to consider the affected public. Smaller animals are perceived as less dangerous than big animals, but there are often fewer problems with vagrant dogs and injured animals if cattle and horses are used.

The most common situation was that the animals were privately owned, but in some cases the animals were owned by the municipality or various associations such as riding schools. Using privately-owned animals was in the short term the most economic alternative and experienced people were available and willing to take responsibility for the animals and observe the laws and regulations.

Practical Preparations are Needed

Most municipalities had done some preparatory work before letting the animals in for grazing eg. clearing of shrubs and unwanted trees, sowing of special plants, building of fences around valuable trees, removal of potentially harmful objects (plastic bags or metal pieces) and making an inventory of the vegetation.

The type of fencing used for the areas differed depending on the animal species used and the functional and aesthetic demands. Fences should be efficient and not dangerous for animals or children. From an aesthetic point of view, a fence should not disturb the general view of the landscape and the fence design should be in keeping with the period of history.

Planning Land Management

The written management plans of the municipalities generally contained some background description with the historical aspects, a description of the present character of the area, visions for the future, starting measures, maintenance measures, a time plan, and a plan for evaluation and budgeting. The management measures consisted of recommendations for aspects such as shrub clearing, pasture trimming, species of animals to be used, and whether the use of fertilisers, herbicides or supplementary feeding was allowed. The visions concerned the number of trees in the area and the look and condition of the sward. The result of the grazing was reported to be satisfactory, even better than had been achieved with mechanical management.

Table 12.7 Comments on Grazing Animals

The status of urban aquaculture is assessed in this chapter and the most important literature and knowledge sources are discussed providing a comprehensive overview that highlights challenges facing decision-makers, planners and stakeholders in developing policies, programmes and management strategies that facilitate sustainable, equitable and safe urban aquaculture. The prevailing characteristics of existing urban aquaculture activities are described and the associated benefits are discussed. The recognised constraints and emerging threats to urban aquaculture are then presented. Following this assessment important knowledge gaps and challenges facing planners, managers and other stakeholders are identified and potential approaches to deal with the issues raised are proposed.

Urban Aquatic Production

Stuart Bunting
David Little William Leschen

Introduction

Water Mimosa production using waste water in Hanoi

The cultivation of fish and aquatic vegetables is widespread throughout many cities in South and Southeast Asia and is found to a lesser extent in Africa, Europe, Latin and North America. Despite growing recognition concerning the roles of urban agriculture, including aquatic production, the importance and potential of growing fish and edible aquatic plants in and around cities remains largely unknown. Urban aquatic production is often intrinsically linked with the livelihoods of a significant number of poor people. Urban aquaculture encompasses a broad array of activities, varying from large-scale extensively managed culture-based fisheries like those in the East Kolkata Wetlands to intensive and high-tech production of freshwater and marine fish in tanks. However, in many Asian developing countries, the production systems involved are frequently semi-intensive utilising wastewater directly from the city as a source of nutrients to increase production. The proximity of aquatic farming systems to urban areas presents a number of problems. These may be especially severe if contamination, through urbanisation and industrialisation, of waste resources traditionally exploited to enhance production causes the quality of fish or plants being cultured to deteriorate or negatively affects productivity. Faced with pollution problems, some farmers opt to intensify production depending less on exploiting human waste resources, and more on utilising feedlot livestock waste or inorganic fertilisers and supplementary feeds to enhance production. However, as with intensification in other agricultural sectors, there are risks associated with adopting such an approach. These will be discussed here. Other farmers adopt alternative strategies to mitigate hazards and minimise risks associated with urban aquatic production, but in many cases it seems that the scale and complexity of problems that urban producers face means it is almost impossible for them to address the underlying causes. Foremost amongst these is the sheer rate and scale of physical transformation that characterises many urban centres; much of this change, inevitably alters social and economic as well as physical landscapes. Productive and viable farms may be converted to concrete and tarmac in the course of just a few years. Such dynamic settings can however offer new opportunities for aquatic farming. Limited coordination amongst urban and rural government agencies, weak and ineffective governance, and limited resources mean that urban producers and their problems are often overlooked or ignored. Despite such constraints, urban aquatic production systems provide food and employment, particularly to the poor, whilst there are many other environmental and social benefits that are assessed in the following sections.

Urban aquaculture is defined here as the practice of aquaculture occurring in urban environments, or areas subject to urbanisation, incorporating by definition peri-urban situations. However, demographic and economic processes giving rise to urbanisation do not occur evenly around urban areas, and many factors influence the rate and extent of urbanisation. Furthermore, urbanisation is not always directly associated with development around pre-existing urban centres. Aquaculture activities (defined in Box 13.1) undertaken in both urban and peri-urban settings share many characteristics. However, we propose that as communities or environments become more urban in nature and the competition with other resource uses develops, then the management of aquaculture must become more intensive, though exceptions and limitations exist. Little and Bunting (2005) provide a more detailed review concerning the basis for development of urban aquaculture.

Urban Aquaculture Systems

Considering the range of urban aquaculture systems, this overview covers the most significant and widespread activities, including aquatic plant production. With many urban centres located in coastal areas, it is also important to note that urban aquaculture, although probably dominated by freshwater production, may also include production in brackish water and marine environments. In this review we build on the aquaculture systems typology proposed by Coche (1982) to better characterise the nature of aquaculture occurring in urban areas and to demonstrate that the intensity at which urban aquaculture is managed varies in response to external pressures and incentives for producers. Coche (1982) defined aquaculture production systems as extensive, semi-intensive and intensive. The main characteristics of systems managed at these different intensities are outlined in Table 13.1.

Conventionally, extensive aquaculture is characterised by the dependence of stock on natural food, however, in most urban and peri-urban settings it can be assumed that natural production in water bodies where extensive aquaculture is practised is enhanced indirectly through nutrient-rich runoff and drainage water. Semi-intensive production routinely involves fertiliser applications to enhance natural food production and / or the provision of low-protein supplementary feed; in urban settings waste resources (agricultural and food processing by-products, offal, hotel and restaurant waste) and direct wastewater applications are exploited. Intensively managed systems, whether in rural or urban settings depend on externally sourced inputs of high protein (>20 percent) feed; but in urban areas entrepreneurs have seized upon opportunities to utilise by-products and waste resources to culture high protein feeds such as tubifix worms and fly larvae to supply aquaculture producers.

Practically, however, these distinctions can become blurred. Many peri-urban culture systems benefit from enhanced natural food production as a consequence of nutrient disposal rather than purposeful fertilisation. Furthermore, in contrast to formal semi-intensive sewage-fed aquaculture, production of aquatic vegetables in nutrient-rich water bodies and canals uses sewage-derived nutrients but there is no control over its concentration, as would be the case in the formal system. Nutrient inputs into many systems may be more or less unregulated although the harvest of products such as fish or plants may be highly managed.

Table 13.1 Characteristics of urban aquaculture systems managed at different intensities

Extensive urban aquaculture

Extensive aquaculture is practised in a number of urban settings; the most notable approach consists of stocking fish in reservoirs and large urban water bodies, followed by recapture after a period of 1-2 years. Accounts of stocking and harvesting fish from urban reservoirs have come from cities such as Brasilia, Brazil (Starling, 1998); Hanoi, Vietnam (Sy and Vien, 2002) and Wuhan, China (Liu and Cai, 1998). Culture-based fisheries in Donghu Lake, Wuhan, which covers 1,500 ha are dependent on stocking millions of silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) seed, and providing nursery areas in dammed coves, net-barred bays and net cages to ensure fingerlings are only released when they are sufficiently large to avoid predation. Predatory fish are also controlled to help limit mortality, whilst bulk harvesting is undertaken after a year when fish are around 1 kg in weight. Owing to enhanced management, production increased from 180 t in 1971 to 1,840 t in 1995. The manipulation of fish stocks in urban reservoirs, through selective stocking and harvesting, has also been employed to control eutrophication, but with variable success (Starling, 1998).

A serious constraint to aquaculture in urban reservoirs is the multiple uses of such water bodies by various groups, often with conflicting interests. The openness of such systems also makes it difficult for those farming fish to monitor hazards such as possible pollution sources, or to keep an eye on the activities of other users. The use of cages or pens may constitute an opportunity for farmers to secure access to parts of common property resources, but access of this type may be difficult to negotiate and is likely to cause conflicts and possibly disadvantage poorer sections of communities. There is a growing body of literature concerning common property resources, and guidelines and best management practices proposed for aquatic resources may be useful in developing equitable access and management strategies for urban aquaculture (see for example Bromley, 1992). Continuous cropping of fish from eutrophic urban water bodies is probably one of the most productive and beneficial systems accessible to the poor in Asian cities. Mara, Edwards, Clark and Mills (1993) predicted that a yield of 13 t ha per year would be achieved through the continuous stocking and harvesting of tilapia from extensive lagoon systems managed for wastewater aquaculture, which is significantly higher than production levels in most semi-intensively managed traditional pond based-systems.

Harvesting tilapia in a wastewater fed lake in Yen So, Hanoi

Cage culture is practised on a large scale in the Saguling-Cirata-Jatiluhur chain of reservoirs downstream of Bandung, Indonesia (Hart, van Dok and Djuangsih, 2002); estimates suggest some 4,425 fish cages, producing a total of 6,000 tonnes per year of tilapia (Oreochromis sp.), are present in the Saguling Reservoir. However, cages and pens are open to the wider environment and as such susceptible to water quality problems. This de facto privatisation of the common pool resource inevitably requires capital assets less available to the poor, who can therefore be quickly excluded from production activities.

It is important to note here that urban wastewater, through nutrient enrichment of receiving water-bodies, can enhance production of wild fisheries. However, little work has been done to quantify the extent and significance of this relationship, whilst most attention is given to ensuring that nutrient enrichment in receiving water bodies does not exceed the environmental carrying capacity, degrading the environment and actually harming capture fisheries. Considering the widespread lack of wastewater treatment facilities in many developing countries, it is likely that drainage water from cities in many countries is flowing to rivers, ponds, lakes and rice fields in urban and peri-urban areas, however, little work has been done to document or quantify this, or to assess the costs and benefits of informal wastewater reuse through aquaculture. Moreover, the environmental, animal and public health risks associated with indiscriminate discharges of wastewater to the wider environment and the subsequent capture and consumption of wild aquatic products require consideration (see the Bangkok case study).

Semi-intensive urban aquaculture

Unlike aquaculture in reservoirs and large lakes, pond-based aquaculture offers farmers greater control over management and permits better surveillance, enabling producers to guard against theft, predation and contamination. Recent accounts of semi-intensive pond­based aquaculture in urban settings have been reported for several counties, including Cuba, Ghana and Tanzania (Abban and Cudjoe, 2005; Coto, 2005; Rana, Anyila, Salie, Mahika, Heck and Young, 2005).

Around Kolkata, West Bengal, India, urban aquaculture is practised in ponds covering an area of approximately 3,500 ha where the majority of production is based on wastewater inputs from canals draining the city. Various historical reasons and government interventions have contributed to the scale and distribution of land holdings in the area. The landowners are commonly absentee landlords and management of the fisheries is largely undertaken by the leaseholders; others are operated by cooperatives and groups of fishermen and a small number are under government control. Recently it was estimated that these urban ponds produce ~18,000 tonnes per year of fish for sale in urban markets, many of which serve poor communities. Bunting, Kundu and Mukherjee (2005) present a detailed account regarding the management of the system and the constraints facing producers (see the Kolkata case study for further information). A similar system has evolved in Thanh Tri District close to Hanoi, Vietnam. Phuong and Tuan (2005) reported that the total area of fish production in peri-urban Hanoi was 3,348 ha with an annual yield of nearly 9,000 t, and that 52 percent of this production was from Thanh Tri district. However, Edwards (2005) noted that owing to land use planning changes outlined by the authorities the fish culture area in Thanh Tri (now Hoang Mai district) was destined to decline and change from traditional semi-intensive systems to intensive or organic farming, with the emphasis on producing high-quality seed and high-value aquaculture species.

People are involved intensively in morning glory pre-processing

Aquatic vegetable production in semi-intensive and intensive systems is widespread and commercially significant around many cities in Southeast Asia. According to Phuong and Tuan (2005) in Hanoi, water spinach (Ipomoea aquatica) is produced throughout the year, whilst water mimosa (Neptunia oleracea) is cultivated only in the summer (April to August) and water dropwort (Oenanthe stolonifera) and water cress (Rorippa nasturtium-aquaticum) are produced in the winter (September to March). Most production occurs in flooded fields, some of which were converted from rice production to generate a higher income; water spinach is also cultivated floating on canals within the city. Water mimosa and water spinach production is reported from peri-urban provinces around Bangkok (Yoonpundh, Dulyapurk and Srithong, 2005). Around Ho Chi Minh City, Vietnam, many farmers in Binh Chanh District have combined water mimosa cultivation with fish production in separate ponds; mimosa providing a daily income whilst the fish consume the duckweed that grows alongside the mimosa (Hung and Huy, 2005).

Duckweed (Lemna and Wolffia spp.) are commonly removed from aquatic vegetable crops in both Vietnam and Thailand for use locally as fish feed. Water spinach is grown in converted rice fields in Thu Duc District utilising wastewater, in some cases water spinach leaves are used to feed cultured fish species such as giant gourami (Osphronemus gouramy) and kissing gourami (Helostoma temmincki) that can readily digest and benefit from them. The operating costs for aquatic vegetable production may be lower than for fish culture, the risks from environmental perturbations less and the potential returns higher. However, aquatic vegetable production in many areas is threatened by land use change and the environmental, animal and public health impacts of applying large quantities of agrochemicals during production remain to be quantified. Relatively, aquatic vegetables may be more robust for urban aquaculture than fish; the investment costs tend to be lower and the vegetable crops tend to be less sensitive to acute loss from pollution than fish.

Semi-intensively managed ponds are frequently observed in towns and cities throughout Asia. Production from urban aquaculture however is not usually considered separately from rural production in regional or national statistics, and consequently it is difficult to assess its extent and relative importance. The considerable production of freshwater aquatic plants is also not generally acknowledged even in national statistics. Risks, costs and benefits associated with small-scale urban aquaculture are poorly defined and understood and this may prohibit investment of time, money or resources in developing enhanced approaches. Risk assessment in relation to household aquaculture practices in urban settings is required if sustainable practices are to be identified and promoted, and is discussed further on in this chapter.

Describing semi-intensive aquaculture production in ponds close to Kumasi, Ghana, Agyapong (1999) noted that tilapia (Oreochromis niloticus) and catfish (Heterobranchus sp.) are farmed in ponds ranging from 12 to 54,000 m2. Poultry manure is widely used to fertilise ponds and supplementary feeding with maize bran, groundnut husk and paste, leaves and coconut fibre is routine. Production from 94 fish farms in the area has been estimated at about 150 tonnes per year. Aquaculture practices that utilise food processing and agricultural by-products, such as poultry manure, are widespread and diverse, and aquaculture has an important role in recycling organic wastes from industrial and urban activities. For example, in Thailand, by-products from chicken processing plants are used to feed catfish (Clarias gariepinus × Clarias macrocephalus) grown in urban aquaculture systems stocked at high densities (Little, Kaewpaitoon and Haitook, 1994). Little and Edwards (2003) provide a framework for the interaction between livestock and fish production in peri-urban conditions, as opposed to rural environments.

Morning glory is sold in retail markets

Integration of aquaculture with wastewater treatment using stabilisation ponds and lagoons is widely advocated and several operational systems have been developed; Mara et al., (1993) describe a rational design approach for lagoon-based wastewater treatment that optimises both wastewater treatment and fish production. Lagoon-based systems have been developed for small municipalities in West Bengal, India (Mara, 1997); design and management approaches for these systems have been derived largely from the traditional urban aquaculture practices close to Kolkata. In Lima, Peru, treated wastewater has been used to produce tilapia and studies have demonstrated that fish cultured in this way are acceptable to consumers and that the proposed approach is economically viable (Moscoso, 2005).

Intensive urban aquaculture

Intensively managed aquaculture operations in urban areas are being developed by entrepreneurs in several countries. Although less land may be required per unit of production for intensive as compared to semi-intensive production units (Bunting, 2001), investment costs associated with establishing intensive systems are comparatively high. The advantage of intensively managed farms is that operators can exert greater control over the operation of the system, better regulating factors such as water quality, feed delivery and stock management. More intensive, less open systems also offer producers greater control over public, animal and environmental health hazards. However, due to high capital and operating costs of intensive systems, in many cases it is only feasible to produce high value products, which are often destined for specialist markets.

In Europe, and North America intensive urban aquaculture systems have been used to produce high value fish such as eel, sea bass, shrimp and tilapia (Browdy and Moss, 2005; Bunting and Little, 2005; Zohar, Tal, Schreier, Steven, Stubblefield and Place, 2005). Often, this is only possible when investment costs are reduced through using redundant buildings or waste heat, for example from power stations, to subsidise operating costs. Further to producing food, examples of urban aquaculture from Europe, North America and other regions demonstrate that the practice is used to produce ornamental species, to create visitor or tourist attractions, or is included as part of social development and educational schemes. In developing countries, intensive urban aquaculture systems do exist, for example, producing ornamental species for regional and export markets, a practice that is being encouraged by the local government around Ho Chi Minh City in response to growing pressure on land resources (Hung and Huy, 2005). Intensive production of catfish has been reported from small areas around Lagos, Nigeria (Rana et al., 2005); in Cuba, the Ministry of the Fishing Industry promotes the concept of 'family aquaculture' which includes intensive fish production in urban systems (Coto, 2005); waste from hotels, cafeterias and factories is used in Bangkok to culture catfish intensively (Little and Bunting, 2005). Other intensively managed farms producing high-value food fish and high-quality seed are destined to emerge in other urban and peri-urban settings in response to market demand, rising land prices and concerns over environmental, animal and public health.

Dynamics

In peri-urban areas, access to larger markets and more consistent and reliable demand, mean that producers are more likely to invest in a wider range of semi-intensive management strategies. The greater availability and concentration of domestic waste, in particular wastewater from urban drainage systems, and by-products from food processing and marketing, mean that producers are also able to exploit such resources, reducing their expenditure on fertilisers and feeds. Apparent subsidies to peri-urban farmers in the form of waste resources offer them a significant advantage over producers with limited access to such production enhancing inputs. In selected examples access to such resources has led to dramatic growth in peri-urban aquaculture and widespread benefits for producers. For example, tilapia seed producers utilising sewage near Ho Chi Minh City have a valuable competitive advantage over other producers in the Mekong Delta, even after including transportation costs (AIT/CAF, 2000). However, despite the benefits of being located close to markets and being able to access waste resources, there are potential constraints associated with undertaking aquaculture in urban areas (which are discussed in the following sections).

Morning Glory

The transition from extensive to semi-intensive may be attributed to various factors, of which greater demand from markets combined with improved marketing channels often constitutes an important driver for intensification. Control of resources, more access to production enhancing inputs, for example, waste resources, food processing by-products and credit to purchase additional seed, feed and labour can also stimulate intensification. In urban settings the transition from semi-intensive to intensive production appears to be driven largely by financial considerations and increased competition for resources, in particular land, but also solid organic and wastewater resources, labour, credit and markets. Intensification also appears to offer producers greater control, enabling them to better safeguard and enhance the quality of products, addressing concerns expressed by consumers regarding possible health hazards. Despite the competitive advantage associated with intensification, several barriers to such a transition can be identified; transaction costs may be high, whilst limited access to knowledge, training, credit, markets and institutional support limit the options and opportunities available to producers. Insecure tenure and poorly defined property rights can also mean that producers are unwilling or unable to invest in intensification or improved management approaches.

Benefits of Urban Aquaculture

Employment, income generation and food security constitute important and tangible benefits of urban aquaculture, in particular, for people from poorer communities. However, wider benefits afforded to society such as managed waste reuse leading to improved public and environmental health protection, economic benefits such as increased tax revenue and subsidised waste management, non-renewable resource recovery. Additional functional and non-functional values may also be attributed to urban aquaculture.

Food security and meeting market demand

Reliable and high level demand for aquatic products in urban markets is a primary driving force behind the development of many urban aquaculture activities. Farmers engaged in urban aquaculture have a number of advantages over rural producers, most notably their proximity to markets means that they, or intermediaries, are able to deliver fresh products in a timely fashion to consumers, potentially securing a market premium. Consumers in many Asian countries prefer to buy live fish as a guarantee of freshness, and for urban aquaculture producers it is possible to supply live fish to the market at little extra cost. Increased supplies of aquatic products to markets from urban aquaculture can also help lower the cost of such commodities, thus making them more accessible to poorer communities. Considering aquaculture at the peri-urban interface of cities such as Hanoi and Kolkata, having access to wastewater means that farmers are able to supply fish throughout the year to urban markets. This is important as many of the markets supplied serve poor communities (Morrice, Chowdhury and Little, 1998) and there is a growing recognition (Punch, Bunting and Kundu, 2002) that in some situations urban aquaculture makes a significant contribution to food security in poor households and communities.

Employment and income

Urban aquaculture can provide employment for large numbers of people. Jobs are created directly as a result of stocking, harvesting, maintainance and management, and indirectly in associated activities such as producing and supplying seed and feed, making nets and boats and transporting and marketing harvested products. Estimates suggest that urban aquaculture around Kolkata provided direct employment for 8,000 people, whilst employment in associated sectors servicing the farms was put at over 20,000 people (Kundu, 1994). Employment of one family member, either directly or indirectly, as a result of aquaculture may provide a valuable source of income, but it cannot be assumed that benefits are divided fairly amongst household members (Harrison Stewart, Stirrat and Muir, 1994). Furthermore, where urban aquaculture is practised on family farms, inequality within households may mean the distribution of tasks unfairly burdens particular individuals. As noted in the previous section, many urban aquaculture systems operate throughout the year, and consequently workers employed in such activities are less vulnerable to seasonal labour demands. However, it should be noted that a seasonal demand for additional labour does occur in some situations, and employment for even short periods may constitute an important component in the portfolio of activities that make up poor livelihoods (Punch et al., 2002).

Resource Recovery

Reusing wastewater and by-products from agriculture and food processing in urban aquaculture offers a possible solution to the problem faced by many farmers in developing countries of limited access to nutrient inputs and water resources. Ensuring the maximum possible benefit is derived from appropriated water resources and nutrients contained in both solid and liquid waste will reduce pressure on the remaining renewable freshwater resource and non-renewable mineral resources. This may contribute to reduced conflict over controversial dam building and mining schemes, and limit environmental degradation. Furthermore, compared to prevailing approaches to disposing of wastewater and solid organic waste in many developing countries, productive reuse of waste resources in urban aquaculture offers a greater degree of environmental protection.

Financial returns generated by urban aquaculture, and in particular where wastewater or agricultural and food processing by-products are employed, could potentially subsidise the development and maintenance of formal collection, treatment and delivery strategies for the waste resources. Mara and Cairncross (1989) noted that for Trujillo, Peru, the approach recommended for development of a lagoon-based wastewater treatment facility was to charge construction costs to the municipality and to charge the local farmers who irrigated their crops with treated wastewater with land and operation costs. Responding to a survey, the local farmers indicated that this was an equitable solution, with the cost of treated wastewater expected to be half of what some of them pay for groundwater.

Household and community health and benefits

Urban aquaculture can help facilitate the managed reuse of waste resources and according to Mara and Cairncross (1989) wastewater reuse through aquaculture, which occurs predominantly in urban settings, could be an important component in the sanitation strategies of poor communities in developing countries. Providing sanitation is an important component of development, and is recognised as being of prime importance in improving the general health of the population, reducing infant mortality and the incidence of severely malnourished individuals with associated physical and mental health problems whilst increasing life expectancy (World Bank, 1992; Ahmed, Zeitlin, Beiser, Super and Greshoff, 1993). Inadequate sanitation results in the degradation and contamination of groundwater and surface water. This in turn leads to a need to boil contaminated water, a process that uses large amounts of fuelwood, and results in atmospheric pollution, and possibly increases in respiratory disease (Birley and Lock, 1999). Nutritional and food security benefits associated with urban aquaculture were noted in the previous section.

Distributing benefits from urban aquaculture to the wider community can occur through the presentation of fish to family and friends as gifts; a custom which was observed to be widespread in the town of Saidpur, Bangladesh (Bunting, 2004). Furthermore, by distributing some fish at harvest time to community members residing closest to the ponds, a pond owner found it was possible to reduce the proportion of missing fish. This was attributed in part to either a reduction in poaching by the recipients or greater vigilance of his neighbours reducing the incidence of poaching and predation; enhanced flood control was another factor cited by the owner.

Burbridge (1994) presents a valuable summary of the most important functions attributed to wetlands. These include biomass production, sediment and carbon storage, filtration and cleansing of water, providing pathways or linkages between ecosystems, acting as buffers and regulating the rate of surface-water flow and groundwater recharge within catchments. Preliminary assessment suggests that a similar range of benefits may be attributed to agroecosystems supporting urban aquaculture close to cities such as Kolkata, Hanoi, Ho Chi Minh and Phnom Penh (Bunting, 2004; Little and Bunting, 2005).

Management of wastewater and by-products as inputs for urban aquaculture could be regarded as a subsidy provided by the farmers to society, reducing the demand for resources placed on local authorities. Depending on their design and operation, urban and peri-urban fishponds receiving wastewater inputs are likely to facilitate a range of physical, chemical, bio-chemical and biological contaminant removal processes similar to those observed in wetlands and lagoons (Watson, Reed, Kadlec, Knight and Whitehouse, 1989; Mara, 1997). Furthermore, assessments by Breaux, Farber and Day (1995) and Brix (1999) demonstrate that constructed wetlands constitute an ecologically sound and cost-effective means of sanitation, especially when compared with conventional waste treatment and management strategies.

Constraints to Urban Aquaculture

In the case of extensive and semi-intensive urban aquaculture practices, several factors threaten their continued operation and constrain development of more refined management strategies. The main factors implicated are described in the following sections. In contrast, however, there appear to be opportunities for intensively managed operations.

Large catfish farmed near Ibadan, Nigeria fetch premium prices in city markets

Urbanisation

Processes of urbanisation, in many cases, constitute the most significant threat to the viability of urban aquaculture. Rural-urban migration continues in many developing countries and migrants looking for employment increase the demand for new settlements and temporary housing, and slums may encroach on agricultural land, but more often become established on embankments, roadsides and derelict land. Conversion of land under for urban aquaculture is related to higher-value residential and industrial developments. Unregulated sprawl at the urban fringe is often seen as an irresistible force, leading to a general reluctance to invest in enhanced management practices and maintaining infrastructure, and generating feelings of insecurity among the inhabitants that have been linked to problems such as vandalism, theft and poaching (Little and Bunting, 2005; Kundu, 1994). Ineffective planning and irregular enforcement of regulations by poorly coordinated and resourced authorities exacerbates the problem.

Labour Migration

Following an investigation of problems affecting the operators of farms in peri-urban Kolkata, Kundu (1994) noted that the loss of labour to more highly paid employment represented a constraint to continued operation. Enhancing benefits derived by the poor from urban aquaculture though increased wages and more secure employment arrangements may contribute to the retention of skilled labourers; an alternative would be to support the more effective transfer of skills to new employees. Where dynamic labour markets exist, with people commonly moving from farming activities to more attractive urban employment, this would create opportunities for under-employed community members and recent migrants.

Competition for markets

When threatened by development during the 1950s, a key argument for retaining a network of ponds and paddy fields in the Salt Lake region to the northeast of Kolkata was its ideal location from which to supply fresh produce to urban markets (Kundu, 1994). With the advent of new roads and increased access to public and private transport, urban markets become accessible to more distant producers. Surveying fish markets in Kolkata, Morrice et al. (1998) noted that the large Indian major carp had mostly been imported from other States, from Uttar Pradesh by truck and from Madras, Orissa, Gujarat and Punjab by train. Market studies from Hanoi and Ho Chi Minh City, Vietnam, have identified an increasing demand for high quality aquatic products from urban consumers, but also note that competition from other producers threatens the market for products from traditional urban aquaculture activities (Hung and Huy, 2005; Phuong and Tuan, 2005).

Changing access patterns for inputs

Inadequate access to wastewater has been identified as a major constraint to continued urban aquaculture in the East Kolkata Wetlands. This situation has arisen due to siltation in the canal network conveying wastewater to the fishponds and the inappropriate management of sluice gates regulating the distribution of wastewater. The priority of the local authorities responsible for urban drainage is to ensure that wastewater is drained effectively and safely from the city, and they are under no obligation to supply the needs of the urban fish farmers. The farmers may find themselves in this position as they do not pay for the waste resource, whilst Kundu (1994) noted that competition between farmers exploiting the wastewater resource could be preventing effective distribution. As a consequence of these problems, the farmers are increasingly employing more manageable, but costly, inorganic fertilisers to sustain production and limit their dependence on unpredictable access to wastewater.

Introduction of a pricing system may be one approach to optimising waste resource use, although care should be taken not to disadvantage poor producers. The potential of developing markets for waste resources in stimulating improved supply channels was highlighted by Furedy, Maclaren and Whitney (1997) who suggested that where traditional waste reuse practices have declined, establishing markets for organic waste may promote separation and collection, increasing the value of this resource to farmers and providing income for those involved in processing. Where formal markets are established, such recognition may in turn demand proper regulation to ensure environmental, animal and public health protection. The use of livestock waste in predominantly fish culture and horticulture areas to the south and east of Bangkok are examples of the networks that develop between producers and users of waste in an environment where communications and infrastructure are well developed (Little and Edwards, 2003).

Contamination

Contamination of surface water resources with domestic and industrial pollution constitutes a widespread threat to urban aquaculture. Biswas and Santra (1998) noted that the heavy metal content of fish purchased from urban and suburban markets in Kolkata was higher than similar products from rural markets. Referring to urban aquaculture in Hanoi, Vietnam, Edwards (1997) noted that water from the Set River is widely used, with water from the To Lich River no longer being suitable owing to industrial pollution. The entire wastewater reuse system in Thanh Tri district was apparently in decline, with the canal network that had fallen into disrepair and rubbish dumped in the canals compounding the problem. Problems of contamination are also reported for the Chinese wastewater aquaculture systems in Han Kou region where accounts suggested that fish produced here smelt and tasted of phenols; grow-out ponds are now used as nurseries for small fish, removing problems of consumer acceptance. Where wastewater or other waste resources are used for urban aquaculture the risks posed by contaminants demand careful assessment and monitoring. Bunting and Little (2003) discuss the implications of this and other potential sources of contamination in urban aquaculture in more detail. Source separation (see also Chapter 9) could provide one practical approach to dealing with growing concern over the contamination of wastewater destined for reuse.

Public health concerns

A number of authors have also described potential health hazards associated with urban aquaculture, and in particular those activities where wastewater reuse is practised (Mara and Cairncross, 1989; Strauss, 1991; Edwards, 1992; Edwards, 2001; Howgate, Bunting, Beveridge and Reilly, 2002). Although several of these reviews make hazards associated with aquaculture explicit, it is much harder to quantify the associated level of risk. For example, the risks associated with products grown using waste resources vary, depending on characteristics of the waste resource, the degree of treatment prior to use, the design and operation of the culture system, husbandry and processing practices, subsequent handling and preparation and susceptibility of the consumer. Reviewing health hazards associated with aquaculture employing wastewater reuse, Mara and Cairncross (1989) identified four groups of people at risk: field workers, crop handlers, local residents and consumers. Bunting (2004) provides a more detailed review of the hazards faced by these different groups, describes factors that influence the degree of risk and outlines potential strategies for mitigation. An emerging threat that requires greater attention is the possible relationship between aquaculture operations, where poultry waste is used as a fertiliser, and the transmission of bird flu to humans (see Box 13.2).

Despite possible health hazards associated with exploiting waste resources in urban aquaculture, it should be noted that adopting formal waste reuse practices incorporating treatment components and procedures for monitoring product quality represents a significant improvement on unregulated informal waste reuse practices. Pal and Das-Gupta (1992) demonstrated that water samples and organs from fish cultured in conventional rain-fed ponds contained certain pathogenic bacteria at concentrations two orders of magnitude greater than similar samples from fishponds receiving wastewater from Kolkata. However, risks posed by urban aquaculture, especially in systems reusing wastewater, should not be underestimated and those responsible for managing such farms should be provided with knowledge on limiting health risks. Schemes for risk identification and evaluation have been proposed by a number of authors (Blumenthal, Strauss, Mara and Cairncross, 1989; Mara and Cairncross, 1989; Strauss, 1991; Shuval, Lampert and Fattal, 1997), however, the development of appropriate materials and tools for operators and local authorities may assist in implementing such measures.

Fish in retail market in periurban Hanoi

Changing social expectations and perceptions

The changing expectations and perceptions of operators, consumers and society may be responsible for the decline observed in, once productive, urban aquaculture systems. As mentioned previously, migration of skilled and experienced employees represents a possible constraint to the continued operation of traditional systems. Box 1: The decline of the wastewater aquaculture system in the wetlands to the east of Calcutta

However, it is important to acknowledge that the expectations of managers and employees are not limited to financial considerations; socio-cultural factors such as social status and conformity demand consideration (Sen, 1995). As consumers become more aware about the origins of the food they eat and get to know that products are derived from urban farming systems, which might be subject to even low level contamination, possibly from traffic fumes or road run-off, their perceptions may be negatively influenced, possibly restricting acceptability (Little and Bunting, 2005). Alternatively, through intensification permitting greater control and consequently quality assurance, it may be that consumers would be willing to pay a premium for products from intensively managed urban systems, and the proximity of urban aquatic production would also address emerging concerns over 'food miles'.

Management constraints

Constraints to urban aquaculture presented above suggest that producers face a number of problems, many of which are beyond their control, but which have a significant influence on the management strategies employed. When practising extensive aquaculture, producers are often unable to exert control over the prevailing hydrology, whilst farmers managing large water areas for semi-intensive aquaculture may find it difficult to regulate all inflows and discharges. In such circumstances, the openness of the culture system may allow contaminants, predators and diseases to enter and nutrients, food resources and stock to escape. The physical openness of many extensive and semi-intensive systems also means there are risks from airborne pollution, particularly agrochemical spray drift, predators such as fish-eating birds, and theft by poachers. Considering that many constraints to production in extensive and semi-intensive aquaculture systems are beyond the control of the farmer, one potential management strategy to limit the risks posed by such hazards is to restrict the openness of the culture system. However, as both extensive and semi-intensive production activities depend on environmental goods and services to supplement inputs from the farmer, restricting the openness of culture systems requires the farmer to either reduce production or to compensate for the loss by increasing inputs.

Although farmers may wish to enhance or intensify production, insecurity of tenure often constrains innovation and investment, with farmers unwilling to invest in new technologies and management techniques, instead wishing to limit their exposure to financial risks. Limited access to finance can also constrain innovation by those willing to invest; Kundu (1994) noted that farmers around Kolkata were unable to access bank loans as they lacked documentary evidence of ownership and cultivation rights. Furthermore, urban aquaculture producers often have limited access to information, even on fundamental aspects such as disease and pest management and seed quality; therefore, development of enhanced dissemination pathways may be an important component in ensuring that farmers information needs are met.

Challenges for Planners, Policy-makers and Natural Resource Managers

The nature, extent and management of urban aquaculture in various settings have been discussed above, and the most significant benefits and constraints associated with this farming activity have been described. However, from this assessment it is apparent that various gaps exist in the knowledge base relating to urban aquaculture and important areas requiring further consideration are discussed below.

Future direction – diversity in adversity?

Many traditional urban aquaculture systems, in particular extensive and semi-intensive systems, are undergoing rapid change in response to burgeoning urbanisation and industrialisation. Assessing the findings of recent research focused on peri-urban communities in Bangkok, Hanoi, Ho Chi Minh City and Phnom Penh, it is possible to identify some common trends and promising future scenarios which may be relevant outside Asia. Of the sixteen communities studied under PAPUSSA it seems likely that eleven would stop growing fish and aquatic plants within five years (Leschen, Little, Bunting and van Veenhuizen, 2005). The reasons behind this can be summarised as increasing pressure on land for residential and industrial construction and increasing environmental problems caused by industrial and chemical discharges in wastewater leading to declining production. The remaining communities are all located on the periphery of the cities, and some have been included within designated 'agricultural production areas' on official urban development plans, which may provide some security and explain their continued interest and involvement in urban aquaculture.

Within all of the communities studied a number of aquatic producers exhibited risk averse management strategies in response to the dynamic and changing environments in which they live. In Bangkok and Ho Chi Minh City certain fish farmers have gone into the production of ornamental fish species, often developing their systems into more intensive lower land use facilities and frequently utilising treated wastewater. In Ho Chi Minh City some hatchery producers have also started cultivating and selling ornamental house plants. Similar livelihoods diversification strategies were observed in Hanoi where adopting a rotation of aquatic plant species, i.e. morning glory, mimosa, watercress and water dropwort, provided farmers with significantly overall higher incomes and some protection from seasonal price fluctuations. Successful aquatic plant producers in Hanoi have also used their profits, and drawn on other human and social assets, to set up small-scale electro-plating workshops producing kitchen and bathroom utensils, whilst in Phnom Penh many of the women working in the cultivation of morning glory in the wastewater-fed Beung Cheung Ek lake have developed other small businesses, including shops and stalls selling food and household items.

Following a considered assessment of findings from Bangkok, Hanoi, Ho Chi Minh City and Phnom Penh, Leschen et al. (2005) concluded that the disappearance of aquaculture from the livelihood strategies of some urban communities is inevitable due to intensifying urbanisation, a process which also involves the gradual shift of urban aquatic production to more peripheral peri-urban areas. This mirrors experiences from other cities around the world where agricultural production has similarly been displaced. However, displacement should not be equated with absolute loss as many of the communities and locations to where aquaculture is relocated are still considered urban or at least peri-urban in nature.

Fish, people, and transport co-mingle at Hanoi's biggest early morning freshwater fish market in Thanh Tri District

New and innovative examples of urban aquaculture are emerging, as exemplified by intensive production of catfish in small areas around Lagos, Nigeria, and examples of family aquaculture from Cuba (Coto, 2005; Rana et al., 2005). And it has been proposed here that other intensively managed farms producing high-value food fish and high-quality seed are destined to emerge in other urban and peri-urban settings in response to market demand, rising land prices and concerns over environmental, animal and public health. Unlike many traditional systems in developing countries, these new urban aqua-farming activities will only require a relatively small area and production will be more intensive, based on supplementary feeding as opposed to waste inputs, thereby avoiding problems related to health risks and consumer acceptance. Innovative urban aquaculture operations being developed in North America and elsewhere are also increasingly regarded as multifunctional, producing food, whilst also contributing to social development, education and environmental protection.

For cities being considered as part of the PAPUSSA study the linkages upon which urban aquaculture depends - access to low-cost by-product and waste inputs and marketing opportunities associated with proximity to the city - remain and continually evolve. Notably, however, in the case of Hanoi the municipal authorities have retained large wetlands and lakes within the city boundaries for aesthetic and flood control reasons, and these remain accessible for aquatic food producers and indeed this is encouraged by the authorities as they believe the residents of Hanoi will equate food production with good environmental health, thus providing reassurance to consumers (Leschen et al., 2005).

The future for growing both aquatic plants and fish using urban wastewater will depend on planners being able to coordinate and develop strategies for the effective separation of industrial waste effluents from domestic sewage. This is desirable from other perspectives too, including other farming groups, such as lower income households who may rely on the cultivation of land vegetables and crops using wastewater as their main, and often only, source of water and nutrients, and in terms of more general environmental protection. However, implementing separation or on-site treatment by industries could prove impractical in larger cities where space may be limited and the costs of modifying existing infrastructure may be prohibitive. However, there are examples from Hanoi, Ho Chi Minh City and Kolkata where the relocation of industries from urban areas to industrial parks and zones should allow the more effective treatment and monitoring of effluents. Smaller provincial cities and towns may be better placed to incorporate aquatic food production in their development plans, but further work would be required to confirm this. There are opportunities for producers to diversify into producing high-value food fish, high-quality seed and ornamental species in intensively managed systems with more controlled environments, but there are financial and technical risks associated with such a strategy.

Stakeholder roles and priorities

Awareness and understanding concerning the roles and priorities of stakeholders, their relationships and associated strengths and weaknesses is an important step when developing planning and management strategies that take into account the demands and expectations of producers, consumers and other community members. The findings from a stakeholder analysis summarised below demonstrate that producers, planners and policymakers have different priorities and agendas.

Results from the PAPUSSA project demonstrated that fish farmers benefited from training and extension more than aquatic plant growers, but both government and non-government organisations remain focused on more commercially oriented aquaculture development in provincial areas. As with plant growers, there was little evidence, except in the case of Bangkok, of group formation or trade associations that might help protect their interests or help in marketing. Fish producers were better represented in urban planning through Fisheries Departments, but still had little influence. Considering local planners and district and commune officials, most local officials had a limited role in providing information and statistics for higher centralised urban policy makers. Overall there is little planned integration of aquaculture with other uses of urban water resources. Centralised planners and policy makers generally lack information about the relative importance and benefits that can be associated with producing fish and aquatic plants in urban environments, or indeed the possible hazards associated with such practices. There has been limited provision for future development or even maintenance of urban fish and aquatic plant cultivation in previous city development plans, but a policy of zoning being implemented in peri-urban Ho Chi Minh City and to a lesser extent around Hanoi does make provision for urban food production, including aquaculture. Priority setting by key stakeholders was largely governed by the most influential government ministries and political and commercial lobbyists.

An interdisciplinary and multi-stakeholder approach is critical in the identification and involvement of the principal stakeholders needed to formulate and implement development plans that can accommodate the continued cultivation of fish and plants in cities (Kundu, Halder, Pal, Saha and Bunting, 2005). Hung and Huy (2005) summarise the findings of a detailed analysis of the institutional linkages and hierarchy within the urban planning and policy process relating to aquatic production systems in Ho Chi Minh City. They note that though the urban authorities have designated some areas for agriculture and aquaculture, areas used for aquaculture outside these zones are undergoing rapid conversion for residential and public construction. Aquaculture rarely has priority in land use planning and often does not feature on the agenda. With limited information on city development plans and the future prospects for urban aquaculture, farmers are reluctant to take risks or invest in aquatic production activities.

Public, animal and environmental health

Public, animal and environmental healthPublic, animal and environmental health Public, animal and environmental health hazards constitute some of the most significant challenges to urban aquaculture, though the risks from such hazards are likely to vary depending on site specific variables. Consequently, where urban aquaculture is practised or proposed, work should be undertaken to identify potential problems and to develop management strategies that minimise risks. The question however of who should be responsible for ensuring such a strategy is implemented may be difficult to answer. Although producers may be well placed to identify possible hazards, in the absence of clear incentives, they are unlikely to take responsibility. Instead local institutions may need to facilitate and support the identification and management of hazards; yet, institutions in many developing countries are unlikely to have the capacity or resources to undertake such a programme.

Where public perceptions of products cultured in urban environments are of concern, such measures may be instrumental in ensuring continued consumer acceptance.

Where generic guidelines have been developed for managing hazards in aquaculture, such as those for Hazard Analysis and Critical Control Point (HACCP) proposed by FAO (1997), it would be desirable to first test their appropriateness for urban aquaculture at the regional or local level. Strategies for managing hazards should also be appropriate for producers, specifically taking into account their access to resources, including finance, labour and knowledge. The development and implementation of a HACCP framework for urban aquaculture could make a significant contribution to improving both the health of workers and food safety. HACCP appears preferable to product monitoring. Although desirable, several limitations have been suggested, constraining development of HACCP for small-scale farmers, therefore, only by working together producers may be able to formulate management plans that minimise risks to the environment, workers, local communities and consumers. Furthermore, given the need to base HACCP on sound scientific principles, it is evident that local government and non-government agencies would have important roles in monitoring, identifying critical control points and assessing the magnitude of the risks posed. Research is currently underway to assess the risks to both consumers and those who work with wastewater and the initial findings have been presented by van der Hoek, Anh, Cam, Vicheth and Dalsgaard (2005). A water sampling programme has also been established for inlets and outlets of different peri-urban wastewater-fed fish and aquatic plant systems in Hanoi and the results will provide indications of the potential of these systems for facilitating the cost-effective treatment of wastewater.

Feeding fish in small basins with worms

Knowledge gaps and critical issues

Problems in accessing information, new knowledge and credit (see Chapter 4) suggest that local government institutions, community-based organisations and non-government organisations have roles to play in providing such services. However, the selection and development of appropriate extension materials and pathways and the formulation of suitable credit arrangements is likely to demand resources and require a participatory working style. This in turn may first demand capacity development within local institutions. However, there is often the question of who is responsible for urban aquaculture, for providing support and technical advice, ensuring product safety and informing consumers and others about such activities. Furthermore, in many cases, the question also is whether urban aquaculture is an activity meriting support from local, national and international organisations.

Despite the apparent importance of this activity in certain situations, in providing employment, producing food or contributing to environmental protection and resource recovery, there is no clear picture of the overall extent of the activity or contribution of products from urban aquaculture to regional or national food supplies. To understand the situation better it would be necessary for institutions that collect and collate aquaculture production data to delineate between production in urban settings and that in rural areas. However, such a distinction may be difficult to make, especially where urban aquaculture is not defined in solely geographical terms.

Ellis and Sumberg (1998) noted that 'the significance of food production in and around towns for the overall quality of life in developing counties should not be exaggerated'. Although urban aquaculture may be important to local communities, contributing to employment and food security, it may only play a minor role at a regional scale. Therefore, institutions, especially urban authorities with limited resources subject to varied demands, need to assess rationally the net benefit for poor communities from helping sustain or supporting the development of urban aquaculture. Such an assessment should involve a broad-based socioeconomic analysis, however, some factors may be difficult to quantify, whilst others may receive a disproportionate weighting depending on the agenda and priorities of those involved; relative merits of competing activities will also require assessment. Clearly the multipurpose roles of urban water bodies, for flood control, amenity uses, wildlife, and broader environmental benefits must be considered in any holistic plan that includes the promotion of aquatic food production.

Acknowledgement

This publication is an output from a project funded by the UK Department for International Development (DFID) for the benefit of developing countries. The views expressed are not necessarily those of DFID. This publication is an output from the PAPUSSA project [contract number ICA4-CT-2002-10020] funded by the INCO-DEV Programme of the European Commission for the benefit of developing countries.

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Aquatic Food Production Systems in Bangkok

Ruangvit Yoonpundh
Varunthat Dulyapurk
Chumpol Srithong

Around 10 million people now reside in densely populated communities within Bangkok. As a result, the demand for food has increased drastically. Of the many varieties of fresh produce available, the city consumers favour aquatic products such as morning glory, water mimosa and freshwater fish. These products are grown primarily in periurban areas around Bangkok.

Aquatic production systems, including farming of edible aquatic plants and fish, play an important role in the livelihoods of many urban dwellers employed as farmers and vendors. Production from inland aquaculture increased to around 280,000 metric tons in 2002, accounting for nearly 10 percent of the total annual fish production in Thailand (Department of Fisheries, 2004). This generates an income of nearly 10,000 million Baht (US$ 250 million) a year. Around 30 percent of this intensive aquatic production is concentrated around Bangkok's periurban areas. For example, in the northern part of Bangkok in particular, hybrid catfish farms produce more than 70 percent of the country's total production of catfish (around 80,000 tons) and extensive water mimosa farming in public canals is found in Pathumthani province. In Nontaburi province, about 40 kilometres west of Bangkok, there are vast areas of intensive morning glory farms. About 20 kilometres south of Bangkok, mixed tilapia and carp polyculture in large ponds and intensive water mimosa farming is common. However, recent changes in water and land use in periurban areas, made to accommodate rapid expansions of housing projects, industrial factories and the construction of a new airport, have seriously impacted some aquatic production communities, forcing them to change their traditional way of life. Agriculture-based communities are thus being moved into urban and industrialised districts and suburbs of the city.

Morning Glory farming on the outskirts of Bangkok

Deterioration of the aquatic environment resulting from these expansions is an important factor directly affecting aquatic production systems. Although the 9^th (2002-2006) National Economic and Social Development Plan (NESD) places priority on decentralisation, aiming to increase control at community level in order to utilise local resources more effectively and sustainably, limitations in the readiness and capacity of these communities have hampered implementation of these plans. Capacity building should include all stakeholders, eg., farmers, extension officers, vendors and policy makers.

In a recent State of the System (SOS) workshop held with a variety of stakeholders in Bangkok it was revealed that the main problems faced by farmers were lack of land and land ownership, high costs of investment and wastewater from communities, factories and village estates (especially during the dry season due to lack of drainage and treatment systems as well as a low sense of personal responsibility towards the public environment). These problems force farmers to increase the intensity of their farming activities and systems in order to increase yields. Intensive farming, particularly in aquatic plant cultivation, uses large amounts of chemical fertilisers and pesticides. Morning glory and water mimosa farmers still lack sufficient knowledge and understanding of chemical use due to their low educational backgrounds and the insufficient number of extension officers available to service all of the farmers. Extension officers are also constrained by their own limited knowledge and time to assist with field work. These problems are compounded by a lack of effective mechanisms for the dissemination of information on chemical toxicity and ineffective laws or regulations on the use of chemicals.

In terms of fish culture, periurban fish farms produce mostly common commercial species such as hybrid catfish, tilapia and carps, which are sold mostly fresh, except for hybrid catfish, which are sold live to markets in Bangkok. Because of high competition and an inadequate marketing system, fish prices are considered low. This means that fish farmers are constantly having to reduce their production costs by using canteen waste and slaughterhouse by-products, which are available locally as fish feed. As a result, water quality in ponds can deteriorate and the water discharged from these ponds can degrade the water quality of local public irrigation canals.

Most aquatic plants and fish produced in the periurban areas are transported to Bangkok's retail markets for trading. The most common Bangkok market system relies on the role of middlemen. The first middleman collects all the aquatic products from a farmer, transports these products and sells them to wholesale markets in both suburban and periurban areas. Then another middleman buys these aquatic products from the wholesale markets and sells them through retail markets in the Bangkok area. In an another common Bangkok market system the producer or farmer himself delivers his products to wholesale markets. This type is predominant for aquatic plant production but uncommon for freshwater fish.

Expansion of the "modern-trade" type market or "supermarket" in suburban and periurban areas of Bangkok in the past five years, along with the Thai government's policy of "food safety" awareness, has resulted in rising consumer demand for cleaner and better-quality products, such as vegetables free from pesticides that are subjected to food safety standards including packaging and certified quality. In the near future, it is likely that food safety concerns and requests for certification will become increasingly common among consumers and buyers, and these demands will influence the production of aquatic vegetables such as morning glory and of freshwater fish such as cultured red tilapia.

Harvesting Morning Glory

The market system can promote all types of such "food safety" labelled foods by demanding better quality standards and charging higher prices (due to higher production costs incurred in forcing farmers to produce just what the buyer or customer wants). However, aquatic products that meet this standard still account for only a small portion of the total range of products sold in the market. Therefore, in order to achieve sustained growth for aquatic products in these changing markets, it will be necessary to place higher priority in the near future on food safety for all aquatic foods, which includes a safe and clean production process.

The government should gain more understanding of how to sustain aquatic production systems in Bangkok's periurban areas as they are an important source of aquatic foods and employment for the local economy. Increased coordination between relevant stakeholders is also important. In addition to these requirements, studies must be undertaken to develop new technologies for wastewater treatment, improved marketing mechanisms and Good Aquaculture Practice (GAP) for green products. Organisation and policy analysis is also needed to cope with current changes.

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The Use of Treated Sewage Water from Settlement Ponds in San Juan, Lima

Julio Moscoso

The "Treatment and Use of Sewage Water" programme started twenty years ago at CEPIS in order to contribute to increasing the sewage water treatment network in the region using technologies that would allow for the removal of pathogenic organisms as well as organic materials. So far, CEPIS together with several other Peruvian institutions have carried out a series of experiments on the treatment and use of sewage water at the BioEcological Complex in San Juan, south of Lima, Peru.

Harvesting Tilapia in the ponds

The research and development project entitled "Aquaculture with treated sewage water in the San Juan settlement ponds" is one of the most important contributions of these institutions. The objective of the project was to treat sewage water in the settlement ponds until it reached a quality appropriate for fish culture.

The research showed the efficiency of settlement ponds in removing parasites (helminth eggs and protozoan cysts), viruses and pathogenic bacteria, including Vibrio cholerae. The settlement ponds in San Juan have the potential to reduce the level of faecal coliforms by 5 logarithms (a factor 10.000) and attain an effluent with 10,000 MNP/100 ml levels. Because the fish ponds were independent systems the concentration of faecal coliforms was reduced to the level recommended by the WHO (100 MPN*/100 ml) for fish culture. No other conventional system can compete with this efficiency in the removal of pathogens, unless the process of effluent disinfection is refined, which would increase costs and make the process and its overall maintenance more complex.

Aquaculture Trials

Some of the preliminary experimental trials in the quaternary settlement ponds were quite satisfactory for the culture of the Nile tilapia (Oreochromis niloticus) and the common carp (Cyprinus carpio), but not for the giant freshwater prawn (Macrobrachium rosembergii). The tilapia is the most resilient and best accepted by the local population, and therefore this was the species selected for our research.

These preliminary trials further demonstrated the impracticality of using settlement ponds for fish culture because such ponds need to be totally drained for harvesting the fisht, thus temporarily stopping the treatment system. Also, the high levels of mud and sedimentation normally produced in the settlement ponds made it difficult to collect the fish at harvest time. Finally it was observed that the frequent fluctuations in water flow were affecting the environmental quality, which directly affected the fish growth and even caused some mortality. It was therefore recommended that the construction and thus the design of the ponds especially for tilapia culture should make provision for the supply of tertiary effluents from the settlement ponds.

Tilapia Culture in Fish Ponds

After constructing an experimental aquaculture unit, the second stage of the project was carried out. This was on sewage water treatment in the settlement ponds to guarantee the health and welfare of the cultured fish in the fish ponds. This effluent, which is rich in nutrients, made the algae blooms (phytoplankton) that were the primary natural food source for the fish.

100 percent of the fish from three out of four experimental cultures were qualified as "very good". In only one experiment, 6 percent of the fish were rejected due to an increase in faecal coliforms (which went over the 100,000 MPN¹/100 ml level) in the effluent that fed the fish ponds. This allowed us to propose 100,000 MPN/100 ml as the health quality standard limit for the effluent used for tilapia culture. It was also observed that tilapia has a great capacity for self-filtering as long as the level of faecal coliforms is reduced for a minimum period of 30 days.

In the subtropical climate of Lima, the growth of Nile tilapia during the warmer months is satisfactory and similar to the rate obtained in tropical climates. A sex-reversed tilapia with an initial weight of 60g can be cultured during the four months of warm weather to reach a commercially-acceptable size of 250g and above, at a density of 2 fish/m². The fish ponds' maximum productivity during the summer season is higher than 30 kg/ha/day, obtained from the initial biomass of 960 kg/ha. The maximum stocking density has been set to 4,400 kg/ha, obtained exclusively with the natural feed produced by the fish ponds and with the water supplied from the settlement ponds. The high production of algae, between 700 to 1600 mg of chlorophyla per litre, demonstrated that the addition of artificial feed complements would not increase the fish biomass. Elimination of this step can reduce production costs by up to 70% and allowed us to produce for US $0.48/kg. In tropical areas it has been estimated that similar systems could be carried out continuously and produce three crops of tilapia a year, tripling the annual productivity per hectare and lowering the production costs even more.

The aquaculture project's initial results were used to elaborate a virtual model to expand commercial farms to sub-tropical and tropical regions. This model also enables economic evaluation and a sensibility analysis to study the profitability variation at different land prices, water treatments and product prices. A new version of the model incorporates the use of sewage water in other farming and forestry activities (see figure 13.1).

Figure 13.1 Settlement ponds in Lima

These products allow CEPIS to promote the use of appropriate technologies in the treatment and use of domestic sewage water throughout the Latin American region, using a training programme that includes workshop courses and technical cooperation with different Latin American and Caribbean countries. All these materials are available at the Sewage Water web-page, which is part of the Virtual Library on the Environmental Health web site (www.cepis.ops-oms.org).

The integrated system of treatment and use of sewage water is a sustainable and viable way to improve living standards in cities. It enables the adequate management of domestic sewage water, which is the main cause of aquatic environmental contamination and the spread and proliferation of intestinal and parasitic illnesses in developing countries.

Planning for Aquatic Production in East Kolkata Wetlands

Nitai Kundu
Mousumi Pal
Stuart Bunting
Nina Halder
Sharmistha Saha

Wastewater aquaculture, as practised in the East Kolkata Wetlands (EKW), has attracted much international attention as a model system for the reuse of urban wastewater and resource recovery. At present the multi-functional wetland ecosystem covers approximately 12,500 ha, and is comprised mainly of 254 fisheries managed for wastewater aquaculture, agricultural land, horticultural plots and residential areas. It constitutes a unique system of resource recovery, in which nutrients are extracted from the city's wastewater through fish farming and agriculture.

In EKW wastewater flows through fish ponds covering about 4,000 ha and these ponds facilitate a wide range of physical, biological and chemical processes which help improve the quality of the water. Consequently this wetland system is popularly known as the kidney of the city and has been described as one of the rare examples of environmental protection and development management in which a complex ecological process has been adopted by the local farmers for mastering the resource recovery activities. The wetland also supports the livelihoods of around 60,000 residents through the fisheries and other socio-economic activities. The existing land-use pattern of the East Kolkata Wetlands (EKW) is summarised in Table 13.2.

Carp raised in aquaculture pond

Table 13.2 Land use in the East Kolkata Wetlands

In August 2002, the EKW area was included in the list maintained by the Ramsar Bureau established under Article 8 (site no.1208) of the Ramsar Convention, which recognises the EKW as a "Wetland of International Importance". The Ramsar Convention plays a vital role by providing certain basic guidelines to draw up suitable plans for the maintenance and sustenance of the wetlands. Among these, the three most important guiding principles are: maintenance of the special characteristics of the ecosystem, wise use of its resources with an eye towards sustainability and economic development for the wetland community.

The major forms of cultivation prevalent in the region are sewage-fed agriculture, garbage farming and sewage-fed aquaculture. In rural areas, paddy farming dominates production whilst potatoes and other vegetables are cultivated using traditional methods. These farming systems are central to the livelihoods of many local poor people.

Fish cultivation in Kolkata's sewage-fed fisheries is a unique feature. There are more than 154 big fisheries or bheries as they are known locally, although fish culture is also practised in numerous small ponds or jhils spread throughout the region. The most important function performed by these wetlands is to recover nutrients from a major proportion of the 1,300 million litres of wastewater discharged from the city daily. The total area of sewage-fed fisheries is around 3,900 ha, privately owned bheris account for 93 percent of this area, farms managed by co-operatives cover 6 percent and ponds managed by the State Government account for less than 1 percent. Large areas of the fisheries are taken on lease and operated by commercial producers, however, several fisheries became cooperatives, either registered or non-registered, because of the inability of the owners to sustain their fishing activities. The fisheries range in size from over 50 ha down to around 5 ha. Various sewage canals supply water to these fisheries, and the water enters the fisheries either via gravity, siphoning or pumping.

Marketing of fish originating from the wetlands has been studied, and almost without exception the total production is sold through wholesale markets at Bantala, Bamanghata, Choubaga and Chingrighata located in the wetlands. From these four major sources fish is distributed to retail markets scattered throughout the core of the city, but there is also evidence that fish is increasingly being marketed in provincial towns.

Recent field surveys showed that 8,500 people are directly engaged in sewage-fed fisheries, of which about 90 percent are from local villages falling within the EKW, the others mainly coming from the adjoining areas of Districts 24-Parganas (North) and 24-Parganas (South), Midnapore and sometimes from neighbouring states. Fish culture presents opportunities for various types of specialised labour, including security services, harvesting work, loading, unloading, packing and distribution of fish, and as a consequence such opportunities often attract migrant labourers from other districts and states. In general, however, traditional economic activities, namely sewage-fed agriculture and fish culture, primarily involve the inhabitants of the EKW. The main stakeholders are the fishermen, farmers, labourers engaged in fish culture and agriculture, night guards and carriers. Furthermore, there are a number of people who stay in the East Kolkata Wetland area and commute to the city for their livelihoods; these people are part and parcel of the system as it has evolved.

A pilot duckweed-based wastewater treatment system in Khulna, Bangladesh

A major problem to the EKW is, for example, siltation of the canals and fishponds. Siltation has reduced the quantity of sewage flowing to the fisheries and made many of the fish ponds much shallower; consequently production has reportedly declined. Such problems are compounded by the adverse effect of notable management failures, including a failure to properly maintain the sluice gates and run the pumping system regulating the storm weather flow and the dry weather flow channels of the Kolkata drainage system in line with the requirements of farmers in the area. As a consequence, sewage-fed agriculture is on the verge of collapse. A number of lift irrigation facilities installed on drainage channels which could alleviate some of the problem are also mostly defunct. Furthermore, a major friction point has emerged between the Kolkata Municipal Corporation and Department of Irrigation and Waterways on the one hand, and the inhabitants of the wetlands who earn their livelihood from the cultivation of rice, fish and vegetables on the other. Many farmers have come to depend on using sewage and garbage from the city as a source of water and nutrients, however, the appropriate management of wastewater and solid organic waste originating from the city is vital to maintaining such a system.

While environmentalists advocate the preservation of the wetlands, speculators are exerting increasing pressure for the right to develop areas for residential and industrial purposes. The wetland is bordered by the city of Kolkata to the west, Salt Lake township to the north-west and the new township of Rajarhat to the north-east. The Eastern Metropolitan Bypass also runs along the western side of the wetlands making the area easily accessible. In combination, these factors are making it increasingly difficult to protect the EKW from developers and real estate agents. Public agencies have also shown a tendency to encroach upon the wetland area for various developmental activities such as locating industries, commercial hubs or public utilities. It is increasingly apparent that the existing legal provisions and agencies responsible for implementing them are unable to prevent such encroachment.

Another source of confusion has been the existence of a plethora of agencies among which the control of the wetland has been distributed. They often work at cross-purposes leading to inaction or in many cases the wrong action. The Kolkata Metropolitan Development Authority was given the responsibility to coordinate developmental activities in the KMA area, which includes all municipalities and corporations coming within its jurisdiction under the Town and Country Planning Act 1979. However, only part of the EKW lies within KMA whilst the remainder is under the jurisdiction of the District Planning Organization under the Panchayats. This convergence of rural and urban governance has been far from effective in the preservation and management of the EKW. Both agriculture and fish culture are suffering due to shortages of wastewater. With proper planning and development of water courses and water bodies and proper management of the sewage disposal system, this major constraint could be addressed. But this would only be possible by ensuring the participation of all stakeholder groups in the decision-making process and subsequent supervision of the proposed activities. An improvement plan for the EKW must address the different types of problems related to the various land-use patterns. Such a plan should also explore possible alternative and better uses that might be permitted within the parameters of the Ramsar Convention.

Resources

Urban Aquaculture
Costa-Pierce, B.A., A. Desbonnet, P. Edwards and D. Baker, 2005. New York Sea Grant, Cornell University, USA. CABI Publishing. 277 pages
Urban Aquaculture is at heart an optimistic book, but it deals with some thorny problems, problems that are all too often ignored. Half of the book is devoted to case studies from both developed and developing countries, which are very illustrative, not only on technical issues, but also on the vitally important social and economic dimensions.

Integrated Livestock-fish Farming Systems, Inland Water Resources and Aquaculture
Little, D.C. and P. Edwards, 2003. FAO. ISBN 92-5-105055-4
The various types of aquaculture form a critical component within agricultural and farming systems development that can contribute to the alleviation of food insecurity, malnutrition and poverty through the provision of food of high nutritional value, income and employment generation, decreased risk of production, improved access to water, sustainable resource management and increased farm sustainability. The objective of the publication is to provide an analysis of the evolution and current status of integrated livestock-fish systems in Asia, particularly East and Southeast Asia, as well as to provide a sound technical basis for considering their relevance for the planning of livestock-fish systems in Africa and Latin America.
http://www.fao.org/documents/show_cdr.asp?url_file=/docrep/006/y5098e/y5098e00.htm

UAM no.14: Urban Aquatic Production
This issue of the UA Magazine presents the findings of the PAPUSSA (Periurban Aquatic Production Systems in South-East Asia) project together with a selection of articles on periurban aquaculture from other parts of the world to an audience broader than only those involved in aquaculture. The section on PAPUSSA aims to give an overview of the status and impact of periurban aquatic production systems in four South-East Asian cities, namely Bangkok, Phnom Penh, Ho Chi Minh City and Hanoi.

http://www.ruaf.org/papussa
PAPUSSA is a 3-year collaborative research project between European and Asian partners funded by the European Union. It seeks to better understand the importance and nature of aquatic food production in and around some of the major cities of Southeast Asia.

www.growfish.com.au
Although originating from the Gippsland Aquaculture Industry in Australia, this portal has a wealth of information, including a report of the visit of a Chinese delegation to the Philippines to study urban aquaculture.

http://www.organicity.org/food/urbaqua/
Rob Freudenberg of Columbia University makes a plea for urban aquaculture in the city in order to use abandoned urban areas and create jobs, and thereby make fresh fish available to the urban community.

www.cityfarmer.org/fish.htm