Gross Erosion Estimation

An attempt has been made to model land degradation in term of water erosion of selected sub-watershed (7710.64 ha.) through RUSLE using ArcGIS interface. The average erosivity of 30 years (1986-2015) annual rainfall using standard formula was estimated to be 480.63 mt-ha./cm. The erodibility factor was computed as 0.236 for clay loam and 0.177 for clay soils using modified formula. The rill to inter-rill erosion ratio was derived from slope map using standard formula. The slope length factor L was derived using Unit Stream Power Erosion and Deposition (USPED) Model. The raster layers of slope steepness factor for slope having 9 % was prepared separately using slope (in degree) raster layer to form final slope steepness factor map. The standard conservation practice factor values for cross-sloped agricultural lands were used to prepare the P factor map. Two different approaches were adopted for prioritization of micro-watersheds. Soil loss tolerance limit of study area was used to derive erosion susceptibility map in order to identify the priority of conservation programs. The priorities of micro-watersheds were decided as d, g, j k, e, f and h. for development Planning.