Estudo comparativo de duas metodologias na definição de unidades geoambientais : Ribeirão do Feijão (São Carlos-SP)

Abstract

The geoenvironmental zoning is considered a inter and multidisciplinary planning instrument of an area, municipality or region, based on the components of the physical environment. Its goal is to support public policies seeking to reconcile economic development and environmental quality. The Ribeirão do Feijão Watershed is located almost entirely in São Carlos-SP, is an area of great interest because is the main source of surface water supply of this city and more than 70% belongs to the recharge area of Botucatu Aquifer. In this perspective, this work aimed to elaborate a two geoenvironmental zoning through two different methodologies (CENDRERO et al, 1990; ZUQUETTE et al. 1993). The methodology includes thematic maps in 1:50.000 scale aided by GIS (Geographic Information Systems), remote sensing, field and laboratorial works. The intermediate result of this research was the development of 12 basics maps (documentation, unconsolidated materials, bedrock, slope, landforms, pedology, use and occupation, erosive evidence, relief, legal restrictions, surface water and CEMPAS) and 5 derived maps (erosion susceptibility, agricultural suitability, slope stability, aquifer vulnerability and quality for preservation).The final results corresponded a synthetic geoenvironmental zoning (Cendrero, et al., 1990), which showed 29 geoenvironmental units and two analytical geoenvironmental zoning that were based on water dynamics (Zoning of the Water Accumulation Potential Areas and Zoning of Potential Infiltration Areas). The Analytical Zoning presented 4 geoenvironmental units, and was more restrictive in defining their units, however the synthetic approach enabled a more comprehensive understanding of the weaknesses and potential of the Ribeirão do Feijão Watershed.