Overland slope calculation - a tool for hydrological analysis and modelling of watersheds.

摘要

This paper deals with the different methods for overland slope calculation particularly in mountainous watersheds. The watersheds selected for this study were: (1) upper part of Chenab river catchment in Himachal Pradesh; (2) lower part of Chenab river catchment in Jammu and Kashmir; and (3) Bhaintan watershed in Tehri-Garwhal district Uttaranchal. Four topographic methods were employed to estimate the watershed mean slope of the three watersheds with areas ranging from 2.77 to 5533.5 km2. Of the four methods used, the mean slope curve method was the most accurate but the most tedious and labourius method. The watershed slopes estimated by the grid contour method, William and Berndt method and Hortons approach are relatively simple and also satisfactory for general purposes..