A national soil erosion survey for Zimbabwe

ZIMBABWE, like many tropical Third World countries, faces widespread land degradation problems. Accelerated soil erosion, due in part to growing pressures on the land from human and livestock populations, is especially common in peasant farming areas. About 4.2 million people or three-quarters of Zimbabwe's population live within such areas ( 1 ). A combination of relatively high population densities, lack of investment, and marginal agricultural terrain has resulted in serious problems of poverty and environmental degradation within peasant farming areas, referred to locally as the Communal Lands. Since the country's independence in 1980, the Zimbabwe government has made major efforts to foster development of the Communal Lands to improve living standards, alleviate population pressures, and provide employment. But excessive soil erosion on arable land, where losses of 40 tons per hectare (18 tons/acre) per year are not uncommon (4), is threatening the viability of farming. On communally managed rangeland the situation is equally serious, if not more so. Apart from erosion's direct effects on agriculture, reservoirs are filling rapidly with sediment, which threatens both domestic and irrigation water supplies (2). Despite a reasonable record of applied research on soil erosion (3, 5, 11 …