Context, Conceptual Framework and Sustainability Indicators | 23

for animal protein in diets, exacerbating already fragile environmental conditions in developing countries and causing further loss of biodiversity.

     Much of livestock production is on small farms, where it is an integrated component of the farming system, often with multipurpose uses (Dolberg, 2001; LivestockNet, 2006). However, there are also nomadic systems, particularly in Africa, in extreme northern Asia, Europe and America (in the tundra) where livestock continues to be the primary source of livelihoods.

Some emerging agricultural systems

Organic agriculture. In the past few years, organic agriculture has developed rapidly with more than 31 million ha in at least 623,174 farms worldwide in 120 countries (Willer and Yussefi, 2006).

     Global sales of organic food and drink increased by about 9% to US$27.8 billion in 2004, with the highest growth in North America, where organic product sales are expanding by over US$1.5 billion per year, with the United States accounting for US$14.5 billion sales in 2005 (Willer and Yussefi, 2006).

     Organic agriculture is a holistic production management system that promotes and enhances agroecosystems health including biodiversity, biological cycles, and soil biological activity (Codex Alementarius Commission, 2001). It emphasizes the use of management practices in preference to the use of off-farm inputs, taking into account that regional conditions require locally adapted systems. This can be accomplished by using, wherever possible, cultural, biological, and mechanical methods instead of using synthetic materials, to fulfill any specific function within the system. Organic agriculture can contribute to socially, economically and ecologically sustainable development, firstly, because organic practices use local resources (local seed varieties, dung, etc.) and secondly, because the market for organic products has high potential and offers opportunities for increasing farmers' income and improving their livelihood. It also contributes to in situ conservation and sustainable use of genetic resources. But organic agriculture also has negative environmental impacts such as overuse of animal manure, which can lead to nitrite pollution of water supplies; on the other hand, insufficient application of organic manure can lead to soil mining and long-term productivity declines (World Bank, 2004a).

     The sustainability of organic agriculture is often debated, with divergent views regarding its feasibility and productivity potential in resource-poor areas. Most information is from temperate countries and the technological needs in low-potential areas are not addressed. Organic production requires a high level of managerial knowledge, the ability to protect crops from pests and diseases, and compliance with production process requirements. Certification is one of the most important cost items. Reliable and independent accreditation and control systems are essential to enforce organic standards and regulations and to meet phytosanitary standards and general quality requirements.

     Urban and peri-urban agriculture refers to growing plants and raising animals for food and other uses within and around cities and towns, and related activities such as the production and delivery of inputs and the processing


and marketing of products (van Veenhuizen, 2006). It has received increasing attention from development organizations and national and local authorities, and is likely to do so in future as well, as migration of poor people from rural to urban areas will continue to be a major trend in developing countries. This results in shifting poverty from rural areas to urban slums and increasing the importance of urban and peri-urban agriculture, as it contributes to reliable food supply and provides employment for a large number of urban poor, especially women (World Bank, 2004a). It is an integral part of the urban economic, social and ecological system (Mougeot, 2000).

     Urban and peri-urban agriculture includes a range of production systems from subsistence production and processing at household level to fully commercialized agriculture. It may include different types of crops (grains, root crops, vegetables, mushrooms, fruit) or animals (poultry, rabbits, goats, sheep, cattle, pigs, guinea pigs, fish) or combinations of these (ETC-Netherlands, 2003). Non-food products include aromatic and medicinal herbs, ornamental plants, tree products (seed, wood, fuel), and tree seedlings. For example in Hanoi, Vietnam, urban and peri-urban agriculture supplies about one-half of the food demand and engages more than 10% of the urban labor force in processing, marketing, retailing, input supply, and seed and seedling production (Anh et al., 2004)

     Urban and peri-urban agriculture is characterized by closeness to markets, high competition for land, limited space, use of urban resources such as organic solid wastes and wastewater, a low degree of farmer organization, mainly perishable products, and a high degree of specialization (van Veenhuizen, 2006). Some critical issues include the use of pesticides; use of urban waste in agricultural production; environmental pollution caused by agricultural activities in densely populated areas; conflicts over land and water between agricultural, industrial, and housing uses; unhygienic food marketing; and inability of producers, wholesalers, retailers and other agents engaged in food processing and marketing to adapt to coordinated food chains (World Bank, 2004a). Urban planning will need to take into account the potential environmental impacts of urban and peri-urban agriculture.

Conservation agriculture. Conservation or zero-tillage agriculture is one of the most important technological innovations in developing countries, as part of Sustainable Land Management approaches. It is a holistic agricultural system that incorporates crop rotations, use of cover crops, and maintenance of plant cover throughout the year, with positive economic, environmental and social impacts (Pieri, et al., 2002). It consists of four broad intertwined management practices: (1) minimal soil disturbance (no plowing and harrowing); (2) maintenance of permanent vegetative soil cover; (3) direct sowing; and (4) sound crop rotation.

     The United States has the longest experience in conservation agriculture approaches, which were first implemented in large and medium-sized farms. Conservation agriculture then began to be widely used in diverse farming systems in Brazil and adapted to small farms in the southern part of the country. It is rapidly being adapted to irrigated rice-wheat systems in the Indo-Gangetic Plains, especially in India,