Assessing the soil erosion susceptibility of watersheds based on morphometric parameters using different MCDM techniques and their evaluation with field survey

The soil erosion susceptibility depends on the morphometric, geological and hydrological conditions of the watershed. Multi-criteria decision-making (MCDM) techniques are generally adopted to identify soil erosion potential zones, however their effectiveness is seldom evaluated against the field observations. In this study soil erosion susceptibility maps are developed for Jhargram District in West Bengal, India, using weighted overlay, cooperative game theory and TOPSIS methods. The outputs of the three MCDM techniques were evaluated against the field survey data and RUSLE model, and their sensitivity to criteria weight was also evaluated. The results of the study suggested that the north-west region of the Jhargram is highly susceptible to the soil erosion. Among the three MCDM techniques, TOPSIS method performed best with 73% accuracy as compared to the field survey data. The cooperative game theory method showed highest sensitivity to criteria weights, while the weighted overlay method showed least sensitivity.