The growth of urban populations in developing countries is accelerating at an unprecedented pace (see Focus 13). Among the myriad challenges this poses, the conditions for supplying cities and towns with foodstuffs raises a series of related questions: will the cities and towns in developing countries have their food increasingly supplied by international markets? Can peri-urban agriculture meet the challenge of food security? Is the growth of markets a vector of local or sub-regional development? Do urbanized lifestyles create nutritional imbalances? The answers vary greatly depending on the continent or region. Observations of trends in Africa or Asia, where food problems are of most concern according to the different projections (Agrimonde, World Bank...), provide some basis for discussion.
The growing influence of markets
In most countries, there is a correlation between urbanization and the per capita increase of food imports. Higher levels of imports signify first and foremost a change of food consumption patterns: urban consumers prefer products that are easy to prepare and regularly available on the markets. Urban consumption of imported cereals (wheat, rice), meat (chicken) and vegetables (potatoes, onions) also rises sharply. Higher imports also point to the problems that food crop farming has to adjust to these changing food consumption patterns. Gradually, food markets become segmented: domestic food products are mainly consumed in the rural areas and secondary urban centres, whereas the imported products are for the main urban centres.
The soaring world food prices in 2007/2008 revealed markedly different situations depending on the country. Today, urbanites in Senegal depend almost entirely on imported rice, which forms their staple diet, whereas those in Mali mainly consume locally grown cereals (rice, maize, sorghum, millet...). Whatever the trend, the question of feeding cities and towns is one of access: in many cases, the standard of living as well as the health of the national economy can compensate for the high level of food dependency. The problems begin when urban dwellers can no longer afford to buy their food.
What's more, urbanization "massifies" the demand for food products, and this necessitates regular provisioning of large quantities of food of consistent quality. Supply systems adapt by developing wholesale trading, which requires investment in infrastructures and information systems (markets, roads, etc.). The search for an economy of scale also reinforces specialization in some production zones. Markets tend to become regional in order to satisfy urban demand. For example, the high plateaus of West Cameroon increasingly supply the coastal towns of Gabon and Equatorial Guinea with market-gardening produce. Overcoming the logistical constraints of supply and distribution networks in order to feed urban centres represents a major challenge for atomized, family production structures.
The growth of cities and towns is also a pivotal vector of technological change for the food crop farmers who find their main outlets in urban areas. This does not involve the intensification of production systems or productivity improvements using industrial inputs (fertilizers, pesticides), as projected by demo-economic or Green Revolution models. In many cases, local farming methods adapt by becoming more labour-intensive (agroforestry, mixed farming systems, etc.). These strategies use and enhance the know-how of local farming communities by optimizing the potential of ecosystems: biodiversity, complementarity between plants or between farming systems, and localized production conditions. Despite their enormous potential and flexibility, the ability of these intensified systems to increase productivity is still barely explored and difficult to measure.
Land pressure in urban areas is causing agriculture to gradually disappear and move out into the surrounding green belts. Often specialized in high value-added market-gardening produce, this type of farming is highly labour-intensive. Given the geographical proximity between production and consumption areas, it is often presented as guaranteeing the freshness and sometimes the health quality of products. In reality, however, the widespread use of inputs to protect crops is threatening food safety, product quality and consumer health, as well as polluting water resources. When agricultural production is sustainably, supported by public policy, this is with a view to social objectives such as generating income for socially marginalized populations, or environmental objectives such as preserving green spaces. Only a few specific production chains for fresh produce, like leafy vegetables and lettuce, are resisting this trend.
Urbanization and nutrition
Sedentary urban lifestyles reduce people's physical activity while offering them a wide choice of food products-some of which are relatively cheap (sugar and fats). The resulting nutritional imbalance is responsible for the explosion of many non-communicable diseases (obesity, diabetes, cardiovascular diseases, etc.) which require health care that is both more costly and more complex than the "classic" infectious diseases. In poorer families, malnutrition is thus taking on extreme forms, and studies have shown that for one person suffering from obesity, one person suffering from serious nutritional deficiencies is to be found within the same family. First observed in the countries and regions experiencing economic and nutritional "transition" (Latin America, South-East Asia, China, North Africa), this trend is now appearing in the large cities in poor countries. Government actions in this domain are not easy to implement as this would mean limiting consumption of certain foods while encouraging a broader diversity and greater consumption of other foodstuffs, against a general backdrop of economic difficulties. Meeting the food requirements of urban populations, both in terms of quantity and quality, is a universal imperative for which solutions need to be found on a specific local scale. It nonetheless requires taking integrating so many levels of information (international prices, regional availabilities, local needs) that it would be difficult to ask local authorities to address these challenges alone.
Cameroon: the limits of maize
Traditionally, cereals are the staple food of North Cameroon populations, who spend nearly 60% of their food budget on these foodstuffs. High demographic growth in this border region is fuelling an ongoing urbanization and a demand for products adapted to urban dwellers: the annual rate of increase of cereal production (4.2%) thus closely matches the annual growth rate of the population in the region (4.5%).
While millet and sorghum are still the two most characteristic crops of North Cameroon, production levels are not keeping apace with these growing needs, and the consumption of other cereals has developed substantially: in 2008, rice accounted for 39% of the household food budget in the region, ahead of maize (36%), millet/sorghum (17%) and pasta (8%). Although a large part of these cereals (wheat, rice, pasta) is imported, local production of maize has developed considerably since 1990 thanks to strong public investment policies, rising from 57,000 tonnes to 500,000 tonnes in 2007. Maize is thus on the point of becoming the region's foremost urban food product, firstly because its price varies little throughout the year and also because it can be cooked in very diverse ways-boiled or grilled ears, sanga, pap, fritters and couscous-, but mainly due to the fact that it has benefited from investments by public authorities.
While this trend appears to show a diversification of local production and improved food security, does it in fact offer a sustainable solution for urban food supply? Can growing maize locally balance out the uncertainties that weigh on the mostly imported supply of rice? Will production be able to meet the increased food demand not only for human consumption but also for livestock feed, or even non-food uses (energy)? Does maize production not mean that food farming in developing countries will be technologically dependent (seeds, inputs) on industrialized countries?
Based on Eric Joël Fofiri Nzossié (Cirad) et al., L'émergence du maïs dans la consommation alimentaire des ménages urbains au Nord-Cameroun (forthcoming).
Ghana | Living on imported rice
Cameroon| Urban market buy from afar
Vietnam | Local Gardening