National Scale Soil Erosion and Sediment Yield Assessment over India

Soil erosion has always been a threat to the environment and agricultural practices throughout the world. For a country like India, where agriculture contributes primarily to its economy, it becomes a major problem. Identifying these vulnerable regions and planning for mitigation is crucial for sustainable soil resource management. For this, mapping or modeling soil erosion at a national scale is required to understand the variability of soil losses throughout the country. Performing field-based experiments to estimate soil losses over a large country is always expensive and tedious. Revised Soil Loss Equation (RUSLE), an empirical model, has been more prominent worldwide due to its simplicity and less forcing data requirements. In this study, average annual Potential Soil Erosion (PSE) was estimated over India using IRED (Indian Rainfall Erosivity Dataset), ISED (Indian Soil Erodibility Dataset), SRTM (Shuttle Radar Topographic Mission), DEM (Digital Elevation Model), and LULC (Land-use/Land-cover) obtained from NRSC (National Remote Sensing Institute) India. PSE was further analyzed using LULC categories and soil types to visualize the impact of soil erosion in each class. As erosion significantly affected agricultural activities, financial losses over the nation were also estimated, considering the severity of soil erosion. Further, Sediment Delivery Ratio (SDR) and Specific Sediment Yield (SSY) were also mapped over the national boundary to visualize the actual soil displacement at a grid scale of 250 m. Using the SSY map, the incoming sediment load to reservoirs/dams/lakes was also estimated considering its watershed areas. This study will be helpful for the experts in the field of sustainable soil resources management for planning mitigation measurements against soil losses in India.

Keywords: Soil Erosion, Sediment Yield, Sediment Delivery Ratio, India, RUSLE, LULC