Natural resource technologies for semi-arid regions of sub-Saharan Africa

摘要

As population pressure and soil degradation have proceeded in the semi-arid zones of sub-Saharan Africa, farmers have responded with a series of labour-intensive measures intended to conserve soil resources. However, on closer inspection, yield effects are also clearly important objectives for the low-income farmers exhibiting high time discount rates, because natural resource management (NRM) investments improve the utilization of available water and are generally combined with soil-fertility improvements. This chapter reviews information available on the diffusion of a number of these technologies and evaluates the constraints to their more rapid diffusion.