RUSLE and SDR model for erosional risk assessment and sediment yield estimation of Achara basin, western coast, India

Abstract

The phenomenon of accelerated soil erosion, the resulting of irresponsible land use practices and human interference bring considerable changes within the Achara basin. The high rate of soil erosion deteriorates the fertility of the soil and consequently reduces crop productivity. Accumulation of transported soil at the lower part of the basin creates a severe problem of sedimentation within the channel and affects the hydraulic characteristics. The estimated potential sediment yield has been derived by using an integrated RUSLE model accompanied remote sensing database in geospatial environment. The result reveals the estimated average annual soil loss for the watershed as 18.81 t ha-1 year-1 . Sediment Delivery Ratio (SDR) fluctuates from 0.01 to 0.627. It has shown remarkably low for almost all parts of the basin, except steep slope and lower part of the watershed depending on the channel gradient of the major river. The junctions of the main channels are more susceptible to accumulate the sediment (> 4 t ha-1 year-1 ) within the basin. The lowermost portion of the basin receives a massive amount of sediment which ranges between 0.01 to 127 t ha-1 year-1 causing sedimentation within the estuary. The attempted work focuses on assessment of the erosional risk and sedimentation issue of Achara basin. The applied model will be helpful in the disaster management planning of such kind of coastal basins in Maharashtra.