Department of Civil Engineering, National Institute of Technology, Tiruchirappalli, Tamilnadu. ssaravananirs@gmail.com
1Present address Department of Soil Science and Agricultural Chemistry, Annamalai University, Chidambaram, Tamilnadu
Soil erosion assessment for watershed management is a world-wide concern for ecologists and land users. In this study soil erosion was predicted using Universal Soil Loss Equation (USLE) for Katteri watershed in Nilgiris, Tamilnadu. Topographically the study area falls under steep slope and undulating terrain comprising 49% of tea plantation, 23% of horticultural crops, and 24% of forest area. The IRS-IC LISS III satellite imagery was classified and used for preparing the landuse/landcover which estimates cover management factor (C) and the landuse practice factor (P). Using digital elevation model (DEM) as input, the slope length factor (LS) was determined by AML programme. Soil erodibility (K) values were measured for all mapped soil types in the study area. The rainfall erosivity factor (R) was directly computed from rainfall intensities. All the above mentioned USLE factors, with associated attribute data, were digitally encoded in a GIS database and converted into 30 m grid cells. Simultaneous overlaid operation on these five layers produced a resultant layer of soil erosion rate in t ha−1 yr−1. This research confirms that remote sensing and GIS provide promising tools for evaluating and mapping soil erosion risk in Katteri watershed.
DEM, GIS, soil erosion, Universal Soil Loss Equation
