Analysis of Geo-Morphometric Indices of Kal River Basin Using Quantum GIS

Abstract

Morphometric parameters are important indicators to understand the hydrological and morphological behavior of river basin. In this study, GIS and remote sensing techniques were effectively used to analyze the morphometric parameters including linear, geometric, basin texture (aerial) and relief aspects of the Kal River Basin in the Raigad district, Maharashtra, India. The work outlines the significance of digital elevation model (SRTM 30m acquired from the USGS Earth Explorer) for assessment of drainage pattern and extraction of relative parameters by using QGIS 3.18 software. The findings of the study categorize Kal River Basin as a 5th order drainage basin based on Strahler order with a total area of 272.64 km². The linear aspects, stream length ratio, bifurcation ratio, and rho coefficient indicated that presence of mountain environment and plateau, dendritic drainage pattern and higher hydrologic storage during floods within the basin. In areal aspects, drainage density (1.18 km/km2), stream frequency (1.03 km2), circulatory ratio (0.19), form factor (0.38), length of overland flow (0.42) and sinuosity index (1.57) implied that area having coarse drainage texture, permeable sub-soil materials, low density of streams, highly elongated shape, younger stage of basin, high length of overland flow during intensive rainfall with more channel erosion and moderate runoff potential and the basin has meandering topology. Further the relief parameters depict geo-morphologically mature stages of the basin development, presence of rolling and gentle slopes in the basin, having complex structures of an erosion prone landscape. These findings underscore the necessity of adopting targeted soil and water conservation measures, promoting vegetation cover restoration, and implementing sustainable watershed management strategies to ensure the long-term hydrological and ecological stability of the Kal River Basin. appropriate measure structure locations for preventing the soil from getting eroded from the study area.