Morphometric Analysis of Khag Micro-Watershed in North-West Himalayas of Kashmir Using GIS and Remote Sensing Techniques

Abstract

Morphometric analysis is of vital importance in any hydrological research and is inevitable in development and management of watershed. Using the watershed as the main unit of morphometric characterization is the most logical choice, as well as geomorphological and hydrological processes take place within the drainage basin. A critical assessment and evaluation of morphometric parameters of Khag micro-watershed was accomplished through measurement of relief, linear and aerial aspects using Geographical Information System (GIS). The watershed boundaries, aspect, slope, digital elevation model (DEM), profile graph of topography, drainage order and drainage density mapswere generated for detailed study of micro-watershed using Shuttle Radar Topographic Mission (SRTM) data. The study area was designated as fourth order basin with the drainage area of 34.32 km2 and shows dendritic drainage pattern. The total length, drainage density and mean bifurcation ratio (Rb) were found to be 38.84 km, 1.13km/km2 and 1.73, respectively. The Khag micro-watershed showed the greater Rb value, which directs a strong structural control in the runoff pattern. A decrease in the stream frequency of flow was also observed with an increase in the order of flow. The shape parameters such as circulatory ratio, elongation ratio, length of over land flow, form factor and drainage texture of Khag micro-watershed were 0.42, 0.56, 0.43 km, 0.24 and 1.66, respectively. The Khag micro-watershed is elongated in shape and dendritic in drainage pattern. This can be attributed to the fact that the lithology and structural controls are more or less uniform. Relative relief and ruggedness number were 0.065 and 2.39 and are likely to subject the micro watershed to maximum soil erosion that demands, instantaneous soil conservation measure to be taken by watershed managers for its stability and sustainability. These studies area advantageous for the planning of rainwater harvesting and the management of the catchment area.