Ponderação de variáveis ambientais para a determinação do Potencial de Uso Conservacionista para o Estado de Minas Gerais

Abstract

The knowledge of the physical environment is a basic assumptionfor the understanding of the environmental relations and for theordering and planning of the land use on watersheds. TheEnvironmental and Productive Zoning of watersheds has been used officially in Minas Gerais State as a tool for the building and the monitoring of socioeconomic and environmental adequation plans. Its steps are the diagnosis of the hydric availability, land use mapping and the landscape unit definition. In the current procedure, the landscape unit definition is manually made, which requires technical knowledge and experience, and leaves place for subjective interpretation and low reproductibility. This work presents the ponderation criteria for an alternative method, which aims to replace the manual delimitation of the landscape units, called the mapping of the conservative use potential. It was built upon the components“soil”, “lithology” and “slope”. The soil classes were ranked according to the drainage, to the fertility, to the texture and to the effective depth. The lithology classes were ranked according to the chemical and mineralogical composition and to the susceptibility to denudation. The slope classes were ranked according to the agricultural capability criteria. The final score values of the components of the use potential were coherent with the empirical observations of the present land use in the State, suggesting that the method may be used as a viable alternative.