Introduction

The tropical and subtropical lands of India have been cultivated for centuries. A very rich civilization has flourished on these lands and they continue to produce food, fodder, fibre, and fuel; the entire countryside is dotted with ancient ponds and tanks – symbols of catchment management, water harvesting, and recycling in the semi-arid/arid areas. These bear ample testimony to the art and science that underlie soil and water conservation. Land degradation is a recent phenomenon primarily related to the historical and political ramifications of the latter half of the 19th century and early part of the 20th century.

The problems of severe soil erosion started, in the second part of the 19th century, with the establishment of British rule and distribution of forested lands to the people. For example, in Ajmer-Merwara (now part of Rajasthan State), all the forest and waste lands were handed over to the people by the British in 1850. The hills were rapidly denuded of timber and grazing was not controlled. The crops in this semi-arid/arid region were irrigated from tanks (ponds) formed by building embankments across ravines. Some of these tanks are indeed very old. The rainfall in this region, though scanty, comes in heavy showers. The water, rushing down in torrents, quickly eroded the hill slopes; the tanks filled up with silt and debris, and the embankments burst. In 1869, less than two decades after the forests were handed over to the people, the region was described as follows: ‘The cattle had perished, the people had fled, large villages were entirely deserted and country was almost depopulated’ (Anon., 1927).