MODELAGEM E MAPEAMENTO DA DEGRADAÇÃO DA CAATINGA

Abstract

Desertification is a land degradation process of the arid, semi-arid and sub-humid natural envi-ronment, almost always associated with the intensification of the erosive effects of rainfall. Nowadays, with the availability of technologies in remote sensing and geoinformatics inventories and diagnostics can to be per-formed with great ease and low cost in large territories. Using these new technologies, this study gathered in-formation on vegetation, topography and soil, in a estimation model of land degradation, that was applied to the watershed of the river Taperoá (5686.4 km2), located on the plateau of Borborema in the state of Paraíba. The results show that the proposed model was able to predict faithfully land degradation in the basin; and despite the high level of degradation of the vegetation (59.2%) and of the susceptibility to erosion of the soil (59.4%), the flat and soft slope in 87% of the lands contributes to minimize the prognosis of the degradation, that shows the predominance of medium-grade class, in 46.2% of the basin. The most critical areas of the basin, with 26.9% coverage, represented by high and very high classes of degradation are concentrated in the lower and the middle third along the drainage, showing there, one of the desertification nucleus of the region Cariri in Parai-ba, where the erodibility of the soil and vegetation degradation are higher.