A STUDY ON THE RATIO OF RELATIVE AND ABSOLUTE ALTITUDE OF KUDIRAIYAR WATERSHED USING GIS

A. Senthilvelan

Volume : VI, Issue : I, January - 2016

A STUDY ON THE RATIO OF RELATIVE AND ABSOLUTE ALTITUDE OF KUDIRAIYAR WATERSHED USING GIS

A. Senthilvelan

Abstract :

Drainage dissection is a significant morphometric tool and is an indicator for estimating the nature and magnitude of dissection in relation to vertical exaggeration of the terrain. It is expressed as the ratio between the relative altitude and absolute height. It is dimensionless because it is expressed always in terms of ratio or percentage. An attempt has been made in this study to analyse the degree of roughness of the surface of the Kudiraiyar watershed. The numerical analysis of areal distribution of dissection index shows that the category of very low dissection index occupies a smaller area (18.31km2) of the watershed. It covers 15.50% of the total dissection area of the watershed. The high and moderate dissection index areas constitute 28.49 km2 (24.12%) and 27.86 (23.58%) km2 respectively. The low dissection index covers 20.39% of the total watershed which occupy 24.09 km2 of the study area. The very high dissection index occupies an area of 19.38 km2 (16.41%).