Mudanças de uso e cobertura da terra e sua relação com a fragmentação florestal e o comportamento hidrológico da bacia hidrográfica do rio Caripi-Pará

Abstract

The process of use and occupation of the northeastern region in Pará and the high fragmentation of forest, indicate impacts in the watershed, which can result in reducing the amount of water responsible for the flow of these systems. This study aimed to develop the multi-temporal mapping in order to define the classes of land use and land cover of the watershed of Caripi river, to evaluate the degree of fragmentation of forest, especially the riparian zones, and simulate their effects on run off behavior. The methodological procedures were: the temporal analysis of classes of land use and land cover from Landsat images; characterization in situ of the landscape units and description of the main environmental systems associated; identification and delineation of riparian zones; application of landscape metrics; and flow behavior estimate by Curve/Number SCS method. The results indicate that the basin is in an advanced state of fragmentation in the middle-higher course. The model and the field observations indicate that it may be affecting the water regime, with a considerable change of the flow, according the form of prevailing land cover. The maintenance of riparian forest in Caripi watershed is required.