Excerpt
SUB-SAHARAN Africa covers 8.6 million square miles (22.2 million km2) in which about 400 million inhabitants live. The Africans have a per-capita gross national product of $235 to $436 (US) and a mean life expectancy of less than 50 years (30, 44, 49). Agriculture in the area is characterized by small-scale, resource-poor farmers.
Agricultural improvements are to be sought on the basis of the locally available inputs and other ecologically compatible technological innovations and intensive use of renewable resources. The inputs not available to most resource-poor formers include agrichemicals, such as fertilizers, insecticides, fungicides, and herbicides; farm power; and motorized equipment. Management options have to consider the nutrient-deficient soils, erratic and unpredictable rainfall, and limited potential of expanding irrigation facilities. Under these situations, the improved technology must be evaluated by a multiple set of system-performance indicators—productivity, stability, sustain-ability, and equity. In contrast to traditional farming techniques, which have low productivity, improved systems must have high productivity, along with high stability and low risks. Suitable technologies, therefore, have to be resource-efficient. For example, the varieties and cropping …
Footnotes
Rattan Lal is a professor of soil physics in the Department of Agronomy, The Ohio State University, Columbus, 43210-1086. He was a soil physicist with the International Institute of Tropical Agriculture, Ibadan, Nigeria, from 1970 to 1987.
- Copyright 1990 by the Soil and Water Conservation Society
This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.