Quantitative Geomorphic evaluation of Dimoru watershed, Assam, India: a Geographical Information System Approach

Abstract

Quantitative geomorphic evaluation of watershed is important to understand the hydro-geomorphological setup of a terrain which is prerequisite for watershed management programs. In the present study, an attempt has been made to study the geomorphic characteristics of Dimoru watershed based on Survey of India toposheets, LANDSAT8 OLI image and ASTER DEM data in GIS environment. Morphometric parameters of the watershed are examined by calculating the linear, aerial and relief aspects with standard methodology. Dimoru watershed is a sixth-ordered basin having very low drainage density value which is indicative of permeable sub-surface with low relief. The mean bifurcation ratio of the watershed is found to be 3.45 which means that the geologic structure do not distort the drainage pattern. The streams of the watershed exhibit dendritic to sub-dendritic pattern and lower order streams dominantly found in the watershed. The elongation ratio of the watershed is 0.28 which reveals the shape of the watershed as elongated one. The result of the study is useful for implementing proper management planning in the watershed.