Ranking sub-watersheds for soil erosion management in the Bhaskel basin using morphometric analysis and MCDM techniques

Abstract

Soil erosion poses a significant challenge to soil conservation, necessitating the prioritization of sub-watersheds for effective resource management and sustainability. This study employs morphometric analysis alongside various multiple criteria decision-making (MCDM) techniques, including the technique for order of preference by similarity to ideal solution (TOPSIS), complex proportional assessment (COPRAS), multi-objective optimisation by ratio analysis (MOORA), additive ratio assessment (ARAS), and simple additive weighting (SAW), to rank sub-watersheds within the Bhaskel basin. The criteria importance through intercriteria correlation (CRITIC) method is used to establish the weights for these MCDM methods. Furthermore, this study introduces an innovative methodology by combining the independent rankings from MCDM and morphometric analyses into a single unified priority map for soil erosion, producing a common ranking for each sub-watershed (SW). The study identified SW1, SW3, and SW6 as high-priority erosion zones needing urgent intervention, while SW2, SW5, SW7, SW9, SW10, and SW11 were medium-priority, requiring mitigation. SW4, SW8, and SW12 were low-priority with minimal erosion but still need monitoring. This integrated approach enhances decision-making by providing a more comprehensive and robust framework for sub-watershed prioritization, enabling policymakers to target high-priority areas with focused conservation and land management strategies crucial for sustainable development.