APPLICATION OF RUSLE TO SMALL WATERSHEDS USING REMOTE SENSING AND ANCILLARY DATA

Abstract

The decisive approach of soil conservation began, when man settled down and began turning pasture land into farm land. The intensive exploitation of the land, disturbed the natural soil vegetative cover and exposed its surface to the effects of erosive agents. Only rarely did man sauced in overpowering the erosive agents and to introduce such forms of agriculture that did not destroy the land. The devastation of land_ by erosion often led to be downfall of civilizations e.g., in Mesopotamia, Syria, China and else where. There are frequent cases of the denudation of the subsoil caused by intensive rainfall which washes away the shallow top soil layer. This has extremely unfavorable consequences for agriculture and forestry considering the long-term process of soil formation because these are the two branches of the national economy, which are most affected by the erosion processes. For planning and implementing erosion control practice to small watershed, the knowledge of gross erosion is essential. Based on 10,000 plot-year data pertaining to the eastern half of the United States, W.H. Wischmeier et.al. developed an equation known as Universal Soil Loss Equation- (USLE). LISLE could not provide satisfactory results when applied to individual storms and watershed level. It was revised later by Williams (1975) known as Revised Universal Soil Loss Equation (RUSLE)