Morphometric Analysis of Nanjangud Taluk, Mysore District, Karnataka, India Using GIS Techniques

An attempt has been made to study drainage morphometry and its influence on hydrology of Nanjanagud taluk. For detailed study, data for preparing DEM, aspect grid and slope maps, geographic information system (GIS) was used in evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the elongated shape of the area is mainly due to guiding effect of thrusting and faulting. In all 41 sub-basins in Nanjangud taluk have been selected for the study. Quantitative morphometric analysis has been carried out for linear, relief and aerial aspects for all the sub-basins. The streams up to fourth order can be seen in all the sub-basins. The morphometric analysis reveals that Hullahalli sub-basin has lower value of drainage density, stream frequency, elongation ratio, relief ratio and infiltration number indicating highly permeable sub-soil materials under dense vegetation cover. Except Hullahalli sub-basin, all the other sub-basins show fractured, resistant, permeable rocks and drainage network seems to be not affected by tectonic disturbances.