ENVIRONMENTAL VULNERABILITY ZONING AND SOIL LOSS EXPECTANCY: IS IT POSSIBLE TO USE USLE FOR THE DETERMINATION OF ENVIRONMENTAL VULNERABILITY?
DOI:
https://doi.org/10.5016/geociencias.v38i4.14083Abstract
In order to ensure the sustaintability of land use practices, enviornomental vulnerability zoning (EVZ) methods are crucial in the occupation of sites in watersheds. Therefore, using as study area the Feijão River Watershed (FRW), São Carlos-SP (Brazil), the EVZ obtained by the Analysis of Natural and Anthropogenic Environmental Fragility (ANAEF) method, with support of the relief dissection index and slopes classes, were compared to the soil loss expectancy (SLE) obtained by the Universal Soil Loss Equation (USLE). This comparison aimed to identify the possibility of using USLE as another method to determine EZV in watersheds. The data were processed in Geographic Information Systems and compared by correct classification rates measured by the confusion matrix for stability classes. The results indicated little coincidence between ANAEF and USLE models, however, the greater influence of the topography associated with anthropogenic activities allowed the USLE to determine fragilities sites not indicated by the ANAEF EVZ method, especially in the headwaters areas. The prediction of water erosion by USLE as a model for EZV could help territorial planning when integrated with ANAEF.