Morphometric analysis in the sub basins of the Kali River using Geographic Information System, Karnataka, India

Abstract

Morphometric analysis serves as a crucial tool for quantitatively characterizing drainage basins and exploring the intricate relationships between hydraulic parameters and geomorphological characteristics. This study presents a comprehensive morphometric analysis of the Kali Subbasin in Karnataka, covering an area of 1175.45 km². Utilizing remote sensing data and GIS tools, we quantified various morphometric parameters, including stream order, stream length, bifurcation ratio, drainage density, stream frequency, form factor, and circularity ratio, to understand the basin's geomorphological and hydrological characteristics. The study area is classified as a seventh-order basin displaying a dendritic drainage pattern with a drainage density of 2.853 km/km². Notably, the bifurcation ratio ranges from 4.396 to 3, indicating low to moderate structural control within the basin. The subbasin's elongated shape, with an elongation ratio of 0.604 and a circularity ratio of 0.298, indicates moderate peak flow and high susceptibility to erosion. Relief parameters showed significant elevation variations, contributing to intense erosion and heightened flood risks in lower-lying areas. The study identifies the basin's transition to a mature geomorphic stage, evidenced by an escalating stream length ratio from lower to higher orders. These findings underscore the importance of tailored watershed management strategies, including floodplain zoning, retention basins, afforestation, and terracing, to mitigate flooding and soil erosion. The study's insights are crucial for developing effective, localized water resource management plans and enhancing the resilience of the Kali Subbasin to future hydrological challenges.