Development and evaluation of GIS-based runoff and sediment yield watershed scale model

A remote sensing and GIS-based watershed scale model has been developed that simulates event-based runoff and sediment yield at each grid of the DEM. The model estimates the runoff and sediment yield in each grid using the natural resources conservation service (NRCS) curve number method and modified universal soil loss equation (MUSLE), respectively, and routes these hydrological parameters using the Muskingum method of routing. The model requires four input files, viz., rainfall, DEM, soil map, and land use map. The model takes the DEM as the primary input which is processed for the determination of various watershed characteristics. The model code for DEM processing, estimation of runoff, and sediment yield and routing is written in Python language and the graphical user interface is written in HTML + JavaScript language. The developed model has been evaluated for its performance on a gauged forest watershed (40.3 ha) located in Shivaliks of North-West India. The test statistics of the developed model indicates reasonably accurate simulation of runoff and sediment yield as is evident from lower values of percent bias (6.40% and − 3.95%), mean bias error (2.52 mm and 0.18 Mg ha−1), mean absolute percent error (1.39 and 0.24) and root mean square error (4.02 mm and 0.29 Mg ha−1), and high values of correlation coefficient (0.936 and 0.974) and Nash–Sutcliffe model efficiency (88.42% and 82.74%). Hence, the developed model can be applied for the simulation of event-based runoff and sediment yield from the watersheds.