Soil Fertility and Hunger in Africa

The fundamental biophysical cause of stagnant per capita food production in Africa is soil fertility depletion. Because mineral fertilizers cost two to six times as much as those sold worldwide, a soil fertility replenishment approach has been developed based on naturally available resources: nitrogen-fixing leguminous tree fallows that accumulate 100 to 200 kg N ha, indigenous rock phosphate applications, and biomass transfers of the nutrient-accumulating shrub Tithonia diversifolia. Tens of thousands of farmers in East and Southern Africa are becoming food secure with these technologies. Soil fertility depletion must be addressed before other technologies and policies can become effective in overcoming…