REMOTE SENSING IN THE RECOGNITION AND MAPPING OF TROPICAL SOILS DEVELOPED ON TOPOGRAPHIC SEQUENCES

The authors compare information on soil maps of the São Paulo region, Brazil (obtained by four different methodologies) with ground truth data and a preexisting semi-detailed soil map. The methodologies for compiling the new soil maps included: (1) conventional (field) cartographic methods; (2) air photo interpretation; (3) automated processing of radiometric data; and (4) use of radiometric data in conjunction with air photo analysis and planimetric/altimetric observations. The remote sensing methodologies produced soil maps similar to the detailed map (1) and substantially better than the pre-existing semi-detailed one. The utility of these techniques to soil surveys at rather large scales, and for tropical soil mapping in general, is assessed.