Applied Water Science (Jul 2017)
Evaluation of morphometric parameters derived from Cartosat-1 DEM using remote sensing and GIS techniques for Budigere Amanikere watershed, Dakshina Pinakini Basin, Karnataka, India
Abstract
Abstract The quantitative analysis of drainage system is an important aspect of characterization of watersheds. Using watershed as a basin unit in morphometric analysis is the most logical choice because all hydrological and geomorphic processes occur within the watershed. The Budigere Amanikere watershed a tributary of Dakshina Pinakini River has been selected for case illustration. Geoinformatics module consisting of ArcGIS 10.3v and Cartosat-1 Digital Elevation Model (DEM) version 1 of resolution 1 arc Sec (~32 m) data obtained from Bhuvan is effectively used. Sheet and gully erosion are identified in parts of the study area. Slope in the watershed indicating moderate to least runoff and negligible soil loss condition. Third and fourth-order sub-watershed analysis is carried out. Mean bifurcation ratio (R b) 3.6 specify there is no dominant influence of geology and structures, low drainage density (D d) 1.12 and low stream frequency (F s) 1.17 implies highly infiltration subsoil material and low runoff, infiltration number (I f)1.3 implies higher infiltration capacity, coarse drainage texture (T) 3.40 shows high permeable subsoil, length of overland flow (L g) 0.45 indicates under very less structural disturbances, less runoff conditions, constant of channel maintenance (C) 0.9 indicates higher permeability of subsoil, elongation ratio (R e) 0.58, circularity ratio (R c) 0.75 and form factor (R f) 0.26 signifies sub-circular to more elongated basin with high infiltration with low runoff. It was observed from the hypsometric curves and hypsometric integral values of the watershed along with their sub basins that the drainage system is attaining a mature stage of geomorphic development. Additionally, Hypsometric curve and hypsometric integral value proves that the infiltration capacity is high as well as runoff is low in the watershed. Thus, these mormometric analyses can be used as an estimator of erosion status of watersheds leading to prioritization for taking up soil and water conservation measures.
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