|Ending Malnutrition by 2020: An Agenda for Change in the Millennium - Final report to the ACC/SCN by the commission on the nutrition challenges of the 21st century (ACC/SCN, 2000, 104 p.)|
|4. Food, Agriculture and Environment: Future Challenges|
The required additional food production will have to be achieved under conditions of shrinking per capita land and water and a number of other constraints.
4.2.1 Yield increases are slowing
Significant expansion of agricultural land is not feasible in most parts of the world, so the increased food production necessary to feed the growing population will have to come from more efficient use of land already under cultivation. However, yield increases are beginning to slow. There is progressive degradation of agricultural lands. Depletion of soil nutrients is a critical problem, particularly in Sub-Saharan Africa. Thus intensive cultivation is leading to a reduced micronutrient content of the crops, e.g. in India. Fertiliser applications to combat these deficiencies are infrequent because of high prices, lack of domestic production, insecure supplies of imported fertiliser and poor distribution. Total resource management of small farming enterprises, as in China (Box 4.1), parts of Vietnam and Indonesia, is sustainable, labour-intensive and does not pollute. This contrasts sharply with modern westernised farms which seem efficient yet require huge inputs of fossil-fuel energy. Pests are another factor hindering further increases in crop yields. Pre- and post-harvest losses due to pests are large in developing countries. However pesticide overuse and misuse compromises human health, causes environmental damage and can lead to pesticide resistance. Integrated pest management schemes combine biological controls and host-plant resistance with the reduced use of chemicals.
4.2.2 There is a shortage of water
Globally, the consumption of fresh water as a proportion of accessible fresh water has almost doubled since 1960 (World Wide Fund for Nature, 1998). Although there is still enough water to meet agricultural needs on a global basis, currently 30 countries are water-stressed - of these, 20 are water-scarce. All developing countries suffer from regional and seasonal shortages. Some regions, e.g. N. Africa, already have a high population for the water available locally and Asia and Kazakhstan are now having to use a high proportion of all the obtainable water in their region. (Falkenmark, 1997). By 2025 water scarcity will cause certain regions, containing 55% of the world's population, to be dependent on food imports (Rosegrant et al., 1998). There are many major gains that can be made by minimising water losses, by altering cropping and agro-forestry to minimise evaporation losses, by using root crops to reduce drainage losses and by altering irrigation schemes. Efficiency of water use can also be improved by agronomic, technical, managerial and policy changes, e.g. in water pricing and legal frameworks.
4.2.3 Degradation of natural resources continues
Soil degradation is a significant cause of crop productivity losses. More than 2 billion hectares of land have been degraded in the past 50 years through overgrazing, desertification, salinization, overuse of agro-chemicals, and population pressure. Sub-Saharan Africa and South Asia are of particular concern - between them they contain two-thirds of the world's degraded land (IFPRI, 1995). Almost half the world's poorest people live on marginal lands, where they are often caught in a downward spiral. Past resource degradation deepens today's poverty, while today's poverty makes it difficult to care for or restore the agricultural resource base (UNDP, 1998). Desertification costs the world: $42 billion in lost income, $9 billion in Africa alone, and the livelihoods of a billion people are at risk (UNDP 1998). Forests bind soil to the ground, regulate water supplies and help govern the climate. About a third of the earth's original forests have disappeared and about two-thirds of what is left has been fundamentally changed (UNDP, 1998). There is no consensus as to how much or where forest should be left for future generations and to maintain biological diversity. The experience of the Machakos District in Kenya shows how lands vulnerable to degradation can support a large population provided technological change is supported by a conducive policy framework and much local initiative.
4.2.4 Crop diversity is declining
Food and health systems in the past depended upon a wide range of crops (see Lost crops of the Incas (1989) and Lost crops of Africa (1996)). This diversity helped to provide both balanced diets and insurance against total crop failure. It also meant that crops suited to different agro-ecological conditions were cultivated, thereby avoiding mono-cultures with the same crop over large areas. With the 'advancement' of civilisation and 'modernisation' of agriculture, the crop-mix in the food security basket started shrinking. Today, about 20 crops dominate the global food scenario and trade (Figure 4.2). Wheat, maize, rice and potatoes have become the most widely grown food crops. There has been a drastic reduction in the crop-mix of the food basket, as well as a steep decline in the genetic diversity of crops grown (Figure 4.3).
Sustainable land use in China
China, with only 8% of the world's arable land, and 22% of the world's population, producing only 4% of greenhouse gases, feeds over 1.2 billion people and has relatively low rates of undernutrition. While there may be pockets of poverty and some undernutrition, this is far less than in India and Bangladesh because most of the food is well distributed. Chinese farmers are leaders in ecological agriculture, wasting little by recycling crop residues, by-products and general waste. The largest irrigation network in the world (built manually) enables China to grow one-third of the world's rice. Several crops are grown in one field in alternate rows, with symbiotic benefit (beans, for example, fixing nitrogen for wheat). Labour-intensive pest control permits limited crop spraying to deal with particular outbreaks.
Self-sufficient communities, such as found in the Pearl River Delta, combine crop growing, stock husbandry, fish farming, and the use of renewable energy. Some fields may have three successive crops a year. Ducks contribute to the fertility offish ponds with their own excreta. Ducks, their eggs and the fish are all sources of high-quality protein. The farming units are self-sufficient in food, fertilizer and energy; they also export their surplus to nearby towns. Banana leaves and sugar-cane fibre serve as fish food and fuel for bio-gas stoves. Villages have large bio-digester devices which break down plant material provided by fast-growing plants such as water hyacinths and Napier grass. Pig manure and human waste also contribute to the production of bio-gas. This eases the demand for fuel wood.
Source: skov (1993); Myers (1995)
4.2.5 Fish stocks are declining
Fish is a key source of protein and other nutrients, especially iron, selenium and iodine. It provides a significant portion of total animal protein intake in the developing world: 22% in low-income food deficit countries (FAO, 1999a). Fish consumption has reached a plateau of about 170 g/week per person in developing countries and 500 g/week per person in industrialized countries. Natural fish stocks cannot keep pace with the increasing demand. Paradoxically, much of the total marine haul capture is unwanted -32% in 1995 (FAO, 1996b). Over-exploitation of natural fish stocks by aggressive and efficient fishing techniques, and severe degradation of marine and coastal environments, have depleted fisheries in many parts of the world. Globally, the average marine fish catch for 1990-95 was double that of 1960 (World Wide Fund for Nature, 1998). Some growth of marine fish production is possible, but only if rapid and sustained efforts are made to improve management and rebuild fish stocks and to restore balance to the marine food chain. Aquaculture (fish farming) is the world's fastest growing food production system, nearly doubling its contribution in the last 10 years. However, aquaculture will not meet the increase in demand for fish in developing countries unless local, low-income communities are involved and aquaculture becomes efficient enough to bring down fish prices.
Figure 4.2 Global production of food crops - 1996
Figure 4.3 America's lost diversity
4.2.6 Climates are changing
The warmer air temperatures, increased atmospheric CO2, raised sea levels and changes in rainfall patterns resulting from projected climate change over the next 60 years will have a significant impact on crop and livestock production. For some crops, warmer temperatures will reduce yields. On the other hand, higher temperatures will enable some crops to be grown in areas where it has not been possible before. The geographical range of maize, sunflower and soybean crops in Europe, for example, is predicted to extend 700-1900 km northwards (McMichael et al., 1996). The increased concentration of CO2 in the atmosphere will also affect crop yields. Wheat, soybeans, rice and potatoes should experience a fertilisation effect from the extra CO2. Those countries already vulnerable to food insecurity and undernutrition are most at risk from climate change. Particularly vulnerable areas include Sub-Saharan Africa, South and South-East Asia, particularly Bangladesh. Some areas, especially low-lying coastal regions, will be more vulnerable to increasingly common extreme weather events such as flooding, hurricanes or cyclones. Some of the impact of climate change may be minimised by adjustments at the farm, national and global level. Nevertheless, the increasing severity of extreme weather events will have high social and economic costs. Climate change could result in as many as 350 million extra people at risk of hunger by 2060 (Rosenzweig and Hillel, 1998). The cost of extreme weather conditions should stimulate policy makers to accept a range of measures to minimise the impact of climate change on food production. Some agricultural options are given in Table 4.1
Possible adjustments to agricultural systems to minimise the impact of climate change
· minor shifts in planting dates
· large shifts in planting
National and international policy options
· creation and maintenance of
seedbanks around the world
4.2.7 Urban centers are growing
The urban population is expected to exceed the rural population by 2005; by 2020 over 60% of the world's population will live in urban areas. The urban population of developing countries is forecast to reach 49% by 2015. The rapid, unplanned urbanisation of the last few decades has serious implications for public health with urban slum populations escalating in an environment without clean water, sanitation and other amenities crucial to health. Rapid urbanisation decreases the land available to agriculture and increases the demand for processed food. The geographical area of cities in the developing world is predicted to double between 1980 and 2000 (World Wide Fund for Nature, 1998). Figure 4.4 depicts the 26 cities which are predicted to have populations of 10 million or more by 2015. To feed a city of this size today, at least 6,000 tonnes of food must be imported each day. Urban agriculture and gardening may become increasingly important in providing fresh food for the needs of urban communities (WHO Europe, in press).
Issues such as water security, food transport systems, and the proper use of sewer systems are important in meeting the demands of these urban populations in the developing world. It is important to provide formal safety nets for the urban poor, which do not undermine a household's own response in face of threats to food security and which are tailored to the local situation (Ruel et al., 1998). Policies which stem the tide of urbanisation are also needed - that is, measures to enable people to stay in their rural environments. Investment in rural communities is crucial to secure livelihoods and reduce poverty. In developing countries, only 20% of the rural population, on average, has access to sanitation compared to an average of 72% in the urban population (UNDP, 1997). Other amenities like schools, improvements in transport (including investment in roads), are also important. Rural development policies with an emphasis on agricultural support and development are needed.
4.2.8 Demand for meat is increasing
In the past, meat consumption in developing countries has grown with increasing income. Per capita meat demand in developing countries is predicted to grow by 43% by 2020. This presents the prospect of a huge increase in the use of cereals for feeding livestock. In industrialized countries, the production of 1 kg of poultry meat, pork and beef requires about 2 kg, 4 kg and 7 kg of grain respectively. On this basis, a 40% increase in total cereal demand is predicted (Rosegrant et al., 1998). In many developing countries, however, most of the feed that animals consume is unsuitable for human consumption, so more can be done to increase meat production without necessarily diverting cereal production from crops for human consumption.
Figure 4.4 Enormous cities, enormous food needs
By 2015, twenty-six cities In the world are expected to have populations of 10 million or more. To feed a city of this size today - for example, Tokyo, Sao Paulo or Mexico City - at least 6,000 tonnes of food must be imported each day.
Source: FAO, 1998b
Research is needed to improve alternative feeding strategies and to provide instruction in good husbandry. Possible approaches include:
the use of household waste, crop residues (i.e. cereal straw, sugar-cane tops, maize stover and bean haulm) or vegetation from scrub, bushes and trees (skov, 1993).
improving the nutritional quality of traditional feed crops or alternative feedstuffs. (Farming techniques to improve the quality of feed crops include ammonia-treated straw. Beef consumption in China has more than doubled between 1991 and 1994 by using this system, and more than 80% of feed has come from crop residues).
the use of alternative sources of meat for human consumption: animals such as rabbits or indigenous birds and wildlife may well be more efficient converters of biomass than poultry.
improving the storage of feeds from times of plenty for times of scarcity.
4.2.9. Sub-Saharan Africa: continuing civil strife and weakened infrastructure
Conflict destroys land, water, and biological and social resources for food production, while military expenditures lower investments in health, education, agricultural and environmental protection (Messer et al., 1998). Resolving hostilities and reversing associated agricultural and economic losses are critical if agriculture and human development outlooks are to improve in the 21st century. Conflict prevention must be a goal of development and emergency assistance programmes. The far greater benefits from investing in social, educational and health initiatives than in spending on military systems need to be set out in stark economic terms for each government which has a low index of human development.
AIDS has compromised or disrupted normal activity at a household, community and national level, especially in Sub-Saharan Africa, because it takes its toll on the productive sector of society. Food production and food security of the family have been affected. The head of the household is often too debilitated and ill to continue to work and many communities are now struggling to cope with the smaller number of adult workers. The intellectual capital of many societies is also being badly eroded. Thus, the region's problems are exacerbated by a weakened infrastructure. Investment in training, capacity-building and institutional development - which have characterised regions such as Latin America, the Caribbean and some Asian countries where progress in nutrition has been made - should be considered for Africa in the 21st century.