Hypsometric analysis of the lesser Himalayan watersheds using geographical information system

Hypsometry of drainage basins (area-elevation analysis) has generally been used to reveal the stages of geomorphic development (stabilized, mature and young). In the present study, two watersheds viz. Saini and Tirthan with their sub basins in the Kullu district of Himachal Pradesh state were considered for hypsometric analysis. These watersheds and their sub basins were delineated from the generated Digital Elevation Model (DEM) using Geographic Information System (GIS). The hypsometric values of Saini watershed (0.51) and Tirthan watershed (0:44) indicated that 51 and 44 per cent of the original rock masses still exist in these watersheds. Further the hypsometric analysis performed on these two watersheds and their sub basins revealed that the Saini watershed and ten of its sub basins are more prone to erosion in comparison to Tirthan and its five sub basins. This finding would emphasize the construction of soil and water conservation measures in the Saini watershed and its sub basins at appropriate locations for controlling further erosion, reducing the sediment outflows and conserve water.