|2020 vision focus 4 - Promoting Sustainable Development in Less-favored Areas (IFPRI, 2000, 18 p.)|
Simeon Ehui, Samuel Benin, and Dunstan Spencer
Simeon Ehui is coordinator of the Livestock Policy Analysis Programme at the International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia, and Samuel Benin is a postdoctoral scientist in that program. Dunstan Spencer is managing director of Dunstan Spencer and Associates. He was formerly director of the Resource and Crop Management Division at the International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria.
Existing models of agricultural intensification (that is, greater agricultural production on the same amount of land) assume that population growth, access to markets, and agricultural potential will lead farmers to adopt new technologies, intensify farming, and use resources sustainably. Yet despite policy reforms and structural and sectoral adjustment programs designed to improve production and marketing incentives for farmers, low agricultural productivity, resource degradation, and poverty are still severe and worsening problems in West Africa. In only a few cases have farming systems evolved into highly productive systems that have substantially increased farmer welfare (such as in the northern guinea savannah of Nigeria). It is well known that establishing intensive farming systems requires making investments (in, for example, animal traction and use of manure), but insufficient attention has been paid to the complex factors and diverse agroecological conditions under which farmers operate and the incentive systems that ensure that appropriate investments are made.
Since agriculture provides a third of gross domestic product, employs about two-thirds of the labor force, and is in many cases the primary provider of foreign exchange, it is unlikely that the West African economies can achieve a significant and sustained recovery unless they can reverse the economic decline of the agricultural sector. Identifying effective policies and investments for sustainable development should start by considering the comparative advantage of various livelihood strategies (pathways of development) in different situations and locations. The main determinants of comparative advantage are agricultural environment, access to markets, and population pressure. This brief considers the comparative advantage of strategies for West Africa based on the four agroecological zones - humid, subhumid, semiarid, and arid - found there. These zones are defined by the amount and distribution of rainfall, temperature, and length of the annual growing period.
THE HUMID ZONE
The humid agroecological zone consists of forests and forest-savannah transition and covers about 10 percent of the region, including Liberia and parts of Cameroon, Cd'Ivoire, Ghana, Guinea, Nigeria, Sierra Leone, and Togo. It receives more than 1,500 millimeters of rainfall annually and has a growing period of 7 to 12 months. The soils are very acidic and easily degraded without vegetative cover. Crop-livestock interactions are low because of trypanosomiasis, which is a major constraint to livestock production.
Agricultural potential is greatest for root crops like cassava and yam and tree crops like cocoa and rubber. Given that most of the tree crops are exported for foreign exchange, investments in roads, which are in poor condition, and market facilities are a high priority. These investments will also increase the profitability of root crops, which are perishable, bulky, and of low value compared with horticultural crops. Making credit available for local processing enterprises will increase the returns to marketing infrastructure.
Because world prices for key agricultural commodities are declining, West African farmers must diversify into high-value commodities and reduce production and marketing costs. To do this, they need modem varieties that are resistant to diseases and respond well to limited amounts of purchased inputs. Improved varieties are also needed for other crops such as yam, plantain, and cocoyam, which contribute to household food security. When households are food secure, they can channel resources into producing more tree and export crops.
There is little potential for animal traction in most parts of this zone. The light soils in this zone make cultivation by hoe easy, and the prevalence of tree stumps makes animal traction unprofitable because of the large investments required for de-stumping. Potential for meat production, however, is high, and investments should focus on making available disease-resistant cattle breeds such as the N'dama and on improving the animal health delivery system. To overcome the feed constraint, researchers should work to increase the digestibility of crop residue biomass (which is plentiful in this zone) that would not otherwise be used by livestock. Given the limited interaction between crop and livestock, and therefore the limited application of manure, other soil fertility maintenance activities such as mulching and alley cropping should be encouraged through extension and education.
THE SUBHUMID ZONE
The subhumid agroecological zone consists of savannah type vegetation and covers about 16 percent of the region, including Guinea-Bissau, parts of the countries that also lie in the humid zone except Liberia, and parts of Benin, Burkina Faso, Mali, and Senegal. The zone receives between 1,000 and 1,500 millimeters of rainfall annually and has a growing period of six to nine months. Leaching of nutrients is less common than in the humid zone, and soil degradation is largely physical, through erosion and loss of structure. Although trypanosomiasis is also a major problem here. mixed crop-livestock systems are more common because of heavier soils, which make operation of the plow profitable, and the absence of tree stumps.
A wide variety of food and forage crops, including maize, millet, sorghum, cassava, yam, groundnut, cowpeas, and leguminous forages, are grown in the zone. It is believed that this zone has the greatest potential in West Africa for producing grain, meat, and milk. The zone cannot realize this potential, however, until it is food secure and can export surplus production. Mechanization would appear promising here because of the lack of trees and flat terrain, but the use of tractors has proved unprofitable because cultivation usually needs to be done within a short period of time, causing conflicts among potential users and preventing the high fixed costs from being spread over a wide area. Strategies should therefore promote animal traction by introducing disease-resistant breeds and improving health infrastructure. In areas with good market access (such as around Kaduna in Nigeria or Bamako in Mali), animal fattening and milk production will be important. Extension, education, and credit for adopting livestock feed technologies such as planting of forage legumes, which help restore soil fertility, will be important in such areas.
Although high-yielding varieties exist for most of the crops cultivated in the zone (such as maize, sorghum, millet, soybean, and cowpeas), they are not widely adopted, especially in areas with poor market access and low precipitation. The high costs of fertilizers required for these high-yielding varieties erode their profitability, especially since the removal of fertilizer subsidies. In addition, demand for food by the non-agricultural sector is weak because of limited urban demand, insufficient exports, and cheap food imports. Therefore, to realize the potential of the zone, modem, stress-resistant varieties that respond well to small amounts of external inputs are needed. These varieties must also meet local tastes so that they can satisfy farmers as well as domestic urban markets or export needs. In addition, efforts to stimulate demand by investing in rural roads, improving marketing, and promoting rural nonfarm work are needed.
THE SEMIARID ZONE
The semiarid agroecological zone covers about 20 percent of the region. The zone receives between 500 and 1,000 millimeters of rainfall annually and has a growing period of three to six months. The soils are poor and deficient in nitrogen and phosphorus. The high temperatures accelerate the degradation of plant organic matter and reduce the water-holding capacity of the soil. The main crops cultivated are sorghum, millet, groundnut, cowpeas, and cotton. In the relatively higher rainfall areas, mixed crop-livestock farming systems dominate, as trypanosomiasis and other livestock diseases are less prevalent than in the humid and subhumid zones. In general livestock production will maintain its comparative advantage as diseases continue to constrain livestock production in the humid and subhumid zones.
Given the poor soils and limited precipitation in this zone, crop production (except cash crops such as groundnut, cowpea, and cotton) is undertaken for subsistence only, with few resources devoted to livestock production, except in areas with good access to markets. To realize the potential of this zone, especially in areas with good market access, investments should focus on extension, education, and credit in livestock fattening programs, milk production, and improved marketing and health facilities. The use of groundnut and cottonseed cakes - protein-rich byproducts of the processing of groundnut oil and cottonseed lint - for livestock feed should facilitate the intensification process. Credit and training should be made available for developing local processing of groundnut oil, cottonseed lint, and feed and for improving the marketing of these products. In remote areas small ruminants, which are easily transportable Over long distances, will be more important than cattle. Generally, extension and animal health care services are needed. Furthermore, education and training in nonfarm activities are vital, especially for people seeking to migrate to more favorable areas.
THE ARID ZONE
The arid agroecological zone covers a large portion of the region (about 54 percent), including mostly Chad, Mali, Mauritania, and Niger. The zone receives less than 500 millimeters of rainfall annually, and the growing period is less than three months. Rain is highly variable and insufficient, and the soils are shallow, saline, calcerous, and low in organic matter, making cropping a risky enterprise. Nomadic and transhumant pastoral systems based on communal grazing are the dominant farming systems. Because of population pressure, range degradation, and increasing conflicts over property rights, intensive livestock production will increase, especially in the less moisture-stressed areas. Therefore, drought-resistant modem varieties and extension and education in soil and water conservation techniques are needed. For many people in this zone, however, migration to more fertile and less moisture-stressed areas to engage in farming or nonfarm activities is the only sustainable livelihood strategy. Therefore, training in intensive crop-livestock farming and in nonfarm activities will be needed.
Some people will remain pastoralists, and for them, improving property rights to a variety of pastures and water resources and the right to move between those resources will be important. This step can improve the use of the sparse water resources and pastures that are dominated by annual grass species.
For further information see Simeon Ehui, Timothy Williams, and Brent Swallow, "Economic Factors and Policies Encouraging Environmentally Detrimental Land Use Practices in Sub-Saharan Africa," Dunstan Spencer and Ousmane Badiane, "Agriculture and Economic Recovery in African Countries," and Keijiro Otsuka and Christopher Delgado, "New Technologies and the Competitiveness of High and Low Potential Rural Areas in Asia and Africa," all in G. H. Peters and D. Hedley, eds., Agricultural Competitiveness: Market Forces and Policy Choice, Proceedings of the 22nd International Conference of Agricultural Economists (Aldershot, U.K.: Dartmouth, 1995). See also Prabhu Pingali, Yves Bigot, and Hans Binswanger, Agricultural Mechanization and the Evolution of Farming Systems in Sub-Saharan Africa (Baltimore, Md., U.S.A.: Johns Hopkins University Press, 1987).