Landsat-TM and SPOT-HRV image data applied to geomorphologic mapping in a section of Taquari river, Brazil

Abstract

This study evaluates the contribution of both Landsat-TM and SPOT-HRV data to geomorphologic mapping in a section of Taquari river (Mato Grosso do Sul State, Brazil). Analogic and digital TM and HRV data of different acquisition times were analyzed. Digital enhancement techniques were applied to these data sets, and multispectral color composites were obtained. Nine relief units were obtained from the analysis and interpretation of TM, HRV and topographic maps, together with information obtained from the field survey. These units were grouped into three categories according to its morphogenesis: structural/denudational forms (scarps), denudational forms (pediments, tables, hills and residual relief) and depositional forms (floodplains, Pantanal, the latter divided in low, medium and high moisture areas). The structural/denudational and denudational relief features were classified according to dissection levels and relief and slope classes. Based on the results, one can conclude that it is possible to elaborate geomorphologic maps based on both TM and HRV data, at 1:100,000 scale. Nevertheless, topographic maps are essential to define more precisely the relief units, as well as the morphometric indices.