Indigenous soil and water conservation in India's semi-arid tropics

Soil erosion is a problem that imposes both on- and off-farm costs. As soil erodes, valuable moisture and nutrients are lost, and the topsoil becomes increasingly shallow. The decline in yields that results is a private cost borne by farmers. Off the farm, downstream rivers and lakes become silted, shortening the productive lives of dams and other man-made structures. Soil particles can also transport pesticide residues, poisoning water supplies downstream. These are costs to society, but not necessarily to farmers.