Application of Entropy-AHP and WASPAS methods for prioritizing the sub watersheds of Teesta River basin in terms of soil erosion susceptibility

Soil erosion, primarily driven by natural and human-induced factors, is a significant contributor to soil degradation and natural disasters. Effective watershed management practices can mitigate these issues. This study aimed to create a soil erosion susceptibility map for the sub-watersheds of the Teesta River using the Weighted Aggregated Sum Product Assessment (WASPAS) model. Ten morphometric parameters were considered to assess susceptibility, including Bifurcation Ratio, Circulatory Ratio, Basin Length, Stream Frequency, Drainage Density, Basin Perimeter, Basin Width, Shape Factor, Drainage Texture, and Elongation Ratio. The relative weights of these parameters were determined using the AHP-ENTROPY method. The integrated weights were then applied in the WASPAS model to rank the sub-watersheds. Results indicate that sub-watersheds Rangit (SW5), Chel (SW14), Rangyong Chhu (SW4), Lhonak Chhu (SW1), Chakung Chhu (SW6), and Lish (SW13) are highly susceptible to soil erosion. These sub-watersheds should be prioritized for conservation efforts. The originality of this study lies in its application of the WASPAS method in the context of soil erosion, providing a more comprehensive and accurate assessment compared to traditional methods.