DYNAMICS OF VEGETABLE COVERAGE IN THE BAHIA SEMIARID: A CASE STUDY OF THE RÃS RIVER BASIN

Abstract

The Rio das Rãs watershed is located in the semi-arid region of Bahia, in the transitional context between the Caatinga and Cerrado biomes. It comprises a synthesis of regional, environmental and anthropic aspects of the semi-arid region of Bahia. Over the last few decades, the basin has been subjected to a series of anthropic pressures, leading to a significant loss of natural vegetation. In this context, the objective of the research was to analyze the space-time dynamics of vegetation cover in types of vegetation in the Cerrado and Caatinga, in the watershed and its surroundings, between the years 1970 and 2019. In order to understand the dynamics of vegetation cover, in space and time, remote sensing and geoprocessing techniques were used. During this period, the reduction in vegetation cover was 360,684.97 ha (18% of the study area), with the first 14 years registering the greatest reductions. The largest remnants of vegetation are located in remote areas (rocky outcrops/residual reliefs). A significant reduction of vegetation was observed in Cerrado and Caatinga areas, surpassing the capacity of these phytophysiognomies to withstand anthropic pressures. What caused the change in land use was, mainly, the prosperous periods of regional agriculture (cotton planting) and the practice of illegal charcoal production.