THE UTILITY OF MULTISENSOR DATA FOR MAPPING ERODED LANDS

The availability of remote sensing data with improved spatial, spectra l and radiometric resolution is now available to fully exploit their p otential for a specific application subject to the relative merits and the limitations of each sensor's data. Presented here is a case study where Landsat MSS and TM; and SPOT MLA data for part of the Bijapur d istrict, southern India, which were acquired on the same day, have bee n evaluated for mapping eroded lands. The approach involves the geomet ric registration of all three data to a common map grid using tie poin ts and third order polynomial transform; and resampling the MSS and TM data to a 20 m by 20 m pixel dimension and radiometric normalization. Thematic maps showing eroded lands were generated on a micro-VAX-base d DIPIX system using a maximum likelihood classifier. Accuracy estimat es were made for the thematic maps following stratified unaligned rand om sampling technique, and subsequently, computing overall accuracy an d Kappa coefficient. Spectral separability and classification accuracy was maximum from SPOT-MLA data followed by a combination of Landsat M SS band 1, SPOT-MLA band 2 and Landsat TM band 4; Landsat TM, a combin ation of Landsat MSS, TM and SPOT MLA; and Landsat MSS data.