Soil erosion estimation using the SWAT model in Hathmati watershed of the Sabarmati river basin

Abstract

This study uses the soil and water assessment tool (SWAT) model to estimate surface runoff and soil erosion in the Hathmati watershed of the Sabarmati river basin in India, covering an area of 1,421.91 km². The SWAT model integrates meteorological data, topography, land use, soil characteristics, and climate data to assess soil erosion over 20 yrs from 2001 to 2020. The simulation includes a 2 yr warm-up, a 13 yr calibration, and a 5 yr validation phase. The model's accuracy is validated with coefficient of determination (R²) and nash sutcliffe efficiency (NSE) values of 0.90 and 0.86, indicating acceptable performance. Results show that soil erosion rates in the Hathmati watershed range from 10 to 40 t ha-1yr-1, with rates exceeding 40 t in some years due to heavy rainfall. Variations in rainfall are the primary cause of differences in erosion rates. Structural and vegetative measures can be implemented to address these issues. The SWAT model is suitable for runoff and soil loss prediction in the Sabarmati river basin.