Remote Sensing and GIS based approach in morphometric analysis of thirteen sub-watersheds of Mand river catchment, Chhattisgarh

The present research highlights the significance of Digital Elevation Model (DEM) and GIS for morphometric analysis of thirteen sub-watersheds of Mand river catchment, Chhattisgarh which lies between 21°42’15.525’’N to 23°4’19.746’’N latitude and 82°50’54.503’’E to 83°36’1.295’’E longitude. Different parameters of various aspects including 6 linear, 12 areal and 7 relief parameters were found out in the environment of GIS. Standard methodology and formulae were applied as suggested by previous research workers in this study. Total area of the Mand river catchment is 5332.07 sq.km. in which WS7 has the maximum area of 943.68 sq.km. and WS2 has the minimum area of 179.56 sq.km. The stream order of watershed ranges from first to fourth order showing dendritic to sub-dendritic type drainage. High stream frequency values are observed in sub-watershed 6, 7, 9 and 11 which are accompanied with high relief and impermeable lithology. In sub-watershed 1, 2 and 4 the slope is relatively lesser and therefore yields less stream frequency value. In the study area, the values of mean bifurcation ratio vary from 2.25 to 6.44. Catchment with high form factors (sub-watershed 9, 10 and 12) experience higher peak flows of lesser duration, whereas elongated catchment with low form factors (sub-watershed 2, 6, 7 and 8) experiences lower peak flows of longer duration. Sub-watershed 7 (Re = 0.585) is most elongated among all sub-watersheds. High relief ratio in sub-watersheds 3 and 8 demonstrates quick time of concentration, more stream flow velocity and was highly prone to erosion than other subwatersheds. The present study shows that hydrological assessment based on SRTM DEM is more precise compared to other available techniques. This morphometric research analyse the watershed characteristics and helps to explain the Mand river catchment's hydrological behaviour.