Micro-Watershed Characterization and Prioritization for Land Degradation Mitigation in the Pasol Gad Watershed of the Central Himalayas, India

Abstract

Mountainous regions face complex challenges, including steep terrain, erratic precipitation patterns, and human-induced changes, which degrade crucial resources like soil and water. This study addresses such challenges in the Pasol Gad watershed by introducing a micro-watershed prioritisation framework to facilitate targeted conservation. A multi-criteria decision analysis (MCDA) approach was employed, analysing morphometric and topo-hydrological parameters through Principal Component Analysis (PCA) integrated with Weighted Sum Analysis (WSA). The study identified ten micro-watersheds within PGW and classified them into high, moderate, and low-priority zones based on their susceptibility to erosion. High-priority micro-watersheds (Juwari Gad, Bahaida Gad, and Khaitoli Gad) exhibited steep slopes, complex drainage patterns, and a higher potential for sediment transport, indicating the need for immediate intervention. Validation using observed patterns of land degradation and landslide occurrences confirmed the reliability of the prioritisation framework. The findings emphasise the importance of watershed-based conservation planning, integrating geomorphological and hydrological assessments to guide sustainable land and water resource management. This study also underscores the role of morphometric analysis in watershed characterisation and prioritisation and in overcoming data limitations in land degradation modelling. The proposed framework can assist policymakers and local stakeholders develop effective conservation strategies to mitigate land degradation in the most vulnerable mountain ecosystems.

Keywords: Watershed Prioritization, Hydro-Geomorphometry, Soil Erosion, Landslide Susceptibility, Multi-Criteria Decision Making (MCDM), Sustainable Land Management