Study of hydrological response of a western Himalayan catchment using morphological parameters
Abstract
In the present study, various morphological parameters representing one dimensional view via linear, two dimensional view via areal and three dimensional view via relief aspects of the catchment have been ex- tracted in GIS environment by partitioning a western Himalayan catchment i.e. Basantar catchment from Jammu and Kashmir state of India into seven sub watersheds (SW1 to SW7). The Study catchment was found to be a sixth order drainage basin as per Strahler stream ordering scheme. The catchment is dominated by either parallel or dendritic drainage patterns in different sub-watersheds. Higher bifurcation ratios between the first and second order streams imply the presence of active gullies in the catchment. Medium to high drainage densities, ranging from 2.443 to 3.882 were found in the study area indicating weak or impermeable subsurface material, high mountainous relief and fine drainage texture. Most of the sub-watersheds are characterized with high relief ratio, relative relief and average slope which are favorable for significant runoff generation even for a small volume of rainfall. In order to prioritize the catchment, a compound index was calculated by considering the individual rank assigned to all seven sub-watersheds based on 13 morphological parameters. Compound ranking evaluated using morphological parameters in the present study may be helpful in identifying the critical areas in an un-gauged catchment and accordingly deciding the treatment measures in volume and space.
