Selection of suitable digital elevation model for analysis of forest cover in different agro-climatic zones of Jharkhand, India

Abstract

Digital Elevation Model (DEM) has wide ranging application in the study and analysis of various environmental and biodiversity conservation issues. Due to geographical variations, the accuracy of DEMs generated from different satellite sources needs to be ascertained for choosing the best suitable DEM for a particular study area. In the present study, the performance of DEM datasets of Cartosat-1 and Shuttle Radar Topography Mission (SRTM) has been evaluated on the basis of slope, aspect, altitude and hill-shade map generated through these DEMs for different agro-climatic zones of Jharkhand. Elevation values deduced through Cartosat-1 and SRTM datasets were compared with actual Ground Control Points (GCP) recorded using Global Positioning System (GPS) for testing their accuracy. The forest cover map was created by Landsat 7 ETM+ data and subsequently superimposed on altitude map, generated using SRTM and Cartosat-1. Further, it was visually compared with the Survey of India topo-sheet (1:50000) for analyzing undulating topography and forest cover of Jharkhand. The comparative study based on different parameters for DEM dataset from Cartosat-1 and SRTM, reveals that SRTM data performed better than Cartosat-1 for the study of forest cover in different agro-climatic zones of Jharkhand.