Prioritizing soil erosion susceptible region of Kempty watershed-based on morphometric, hypsometry, forest, and soil using multi-criteria analysis

Abstract

Soil erosion is the main driving force of several devastating natural hazards in the complex mountainous terrain of the Himalayas. The significant impact of soil erosion includes poor soil productivity and soil type, degraded water quality, land degradation, sedimentation, siltation and ultimately biodiversity losses. Hence, it is necessary to assess soil erosion and prioritize the susceptibility regions for effective control measures to serve as baseline data. The present study attempted to analyze the various morphometric, forest, and soil type parameters through Geographical Information System (GIS) and Multi-Criteria Analysis (MCA) techniques for the identification of soil erosion susceptible regions in forest-imparted Kempty watershed, Mussoorie (Dehradun, Uttarakhand, India). The watershed has been divided into four sub-watersheds (SWS1, SWS2, SWS3, and SWS4) using topographic maps (1:50,000 scale and 20 m contours) and ASTER DEM (30 m resolution). Ranking sub-watersheds that significantly influence erosion has been done based on the integrated analysis of morphometric parameters with forest cover, slope, soil, and hypsometric parameters using MCA. Ranks were integrated with MCA to give in four major classes, i.e., classified from 1 to 4 in which, rank 1 indicates the highest priority; while 4 indicates the lowest priority. Notably, MCA priority ranks depicted that SWS4 has the lowest Cp value (2.27) followed by SWS1 (2.36) suggesting very high priority; whereas, the highest Cp value (2.73) of SWS2 and SWS3 (2.52) showed low priority and medium priority, respectively. The prioritization findings identified as a soil erosion-susceptible area can be recommended for adequate control measures for soil erosion and to reduce surface runoff.