Improving Soil Fertility Management in Sub-Saharan Africa

[摘要] There are more than 60 millionsmallholder farmers in Sub-Saharan Africa (SSA). Decliningsoil fertility is a fundamental impediment to agriculturalgrowth and a major reason for slow growth in food productionin SSA. In Africa, as a result of soil degradation,irrigated lands may be, on average, 7 percent below theirpotential productivity, rain-fed crop lands 14 percent belowtheir potential and rangelands 45 percent below potential.Compared to parts of North America, Europe and of Asia, mostSSA soils are naturally not very fertile. Low in a number ofchemical constituents such as phosphorus, sulphur, magnesiumand zinc, low amounts of soil organic matter (SOM) combinedwith poor land cover have resulted in poor soil structure,limited rooting depth and susceptibility to acceleratederosion. However, similar soils in other parts of the worldhave been made highly productive by using appropriatemanagement techniques. There are two main approaches toimproved soil fertility management. One is to attempt tomeet plant requirements with purchased mineral fertilizers.The second relies on biological processes to optimizenutrient recycling, with little reliance on externalchemical fertilizers, but maximizing the efficiency of theiruse. The more sustainable middle path borrows the bestfeatures from both and is referred to as IntegratedNutrition Management (INM). INM combines mineral fertilizerswith organic resources, thus increasing fertilizer useefficiency, reducing the risks of acidification andproviding a more balanced supply of nutrients.

[发布机构] World Bank, Washington, DC

[学科分类] 社会科学、人文和艺术（综合）

[关键词] ACCESS TO INFORMATION;AGRICULTURAL EXTENSION;AGRICULTURAL GROWTH;AGRICULTURAL RESEARCH;CHEMICAL FERTILIZERS