Evolução espaço-temporal dos biótopos (1985-2023) e suas relações com o represamento hidrelétrico da UHE Barra do Braúna, Minas Gerais

Abstract

The significant increase of the water level, resulting from the formation of the reservoir of the Hydroelectric Power Plant - HPP Barra do Braúna, in 2007 - an effect happened in the Zona da Mata Mineira, comprising the Municipalities of Cataguases, Leopoldina, Recreio and Laranjal - establishes fundamental disruptive dynamics that force the reorganization of elements inscribed in the landscape. Understanding the conceptualization of biotopes through the systemic interaction of vegetation cover with local geomorphology, the research, in turn, aims to identify and classify the temporal evolution of biotopes in the plant's area of influence, comparing pre-damming (1985) and post-damming (2023) scenarios through an investigation supported by a geosystemic approach, understanding the landscape as a dynamic system where interactions between biocenosis and physical substrate are mediated by landscape occupation. On the other hand, the methodology was based on the processing of orbital images via Google Earth Engine (GEE), land use and land cover mapping, and geomorphological surveys, in addition to biotope maps at different temporal scales (1:50,000 scale), complemented by fieldwork for detailing at a 1:10,000 scale. The results reveal that the implementation of the plant caused a structural rupture: in aggradation landforms, flat areas were mostly occupied by the water surface, while undulating slopes maintained the predominance of pastures. The study also identified the conversion of lotic aquatic biotopes into lentic ones, as well as the emergence of anthropogenic biotopes, such as spaces dedicated to tourism and leisure areas, which replaced former subsistence areas and native forest fragments. Therefore, it is verified that the landscape evolved into a reorganization oriented by socio-environmental changes, where the fragmentation and the isolation of the vegetation patches indicate the abrupt crossing of the thresholds imposed by nature in the face of the logic of occupation imposed by the reservoir.