Morphometric evaluation and geospatial prioritization of micro-watersheds for Pashupathihal sub-watershed, Dharwad district of Karnataka, India

Abstract

Morphometric analysis of a watershed provides a quantitative description of the drainage system which is an important aspect of the characterization of watersheds. Remote sensing techniques using satellite images are convenient tools for morphometric analysis. The morphometric assessment helps to elaborate a primary hydrological diagnosis in order to predict approximate behavior of a watershed if correctly coupled with geomorphology and geology. Morphometric analysis has been attempted for prioritization for Eight micro-watersheds of Pashupathihal sub-watershed in Dharwad district of Karnataka state. micro-watersheds are delineated by ArcGIS 10.8.2 software as per digital elevation model (DEM). In the present study, Drainage density of the sub-watershed varies between 0.86 to4.92 km/km2 and has very coarse to coarse drainage texture. The stream length ratio was found 33.68 and relief ratio range from 0.015 to 0.025. The mean bifurcation ratio varies from 3.17 to 13.00 which falls under normal basin category. The elongation ratio of the Pashupathihal sub-watershed possesses elongated pattern. Finally, the prioritized score on the basis of morphometric behavior of each micro-watershed is assigned and thereafter consolidated scores have been estimated to identify the most sensitive parameters. Remote sensing techniques proved the competent tool in morphometric analysis and it can be used for estimation of erosion status of watersheds leading to prioritization for taking up soil and water conservation measures for sustainable development of the watershed.