Efeitos da construção de linhas de transmissão previstas na Amazônia: uma perspectiva para a riqueza de mamíferos arborícolas, RJ

Abstract

Rapid urbanization and population expansion are viewed as threats to sustainability. Due to the increased energy demand caused by these processes, more electricity must be produced, and power lines must be extended (LTs). Even while these activities only slightly alter the habitat, they significantly alter the landscape, exacerbating the impacts of habitat fragmentation through edge effects and loss of conectivity. In the last 14 years, 2020 had the highest rate of deforestation in the Amazon rainforest. Arboreal mammals may be particularly impacted by habitat loss and fragmentation since they rely on forested habitats for movement, reproduction, and shelter. Even though there is an increasing need for more LTs, nothing is known about how their installation would affect the diversity of arboreal mammals, which is why this study's goal is to fill that knowledge gap. Following the selection of LTs from the IBAMA online database, analysis was conducted considering the two criteria of being in the Brazilian Amazon biome and not having an installation license. An analysis of the literature was done to identify the arboreal species that might exist in the area, and information on taxonomy, habitat use, distribution, conservation status, body weight, and home range was recorded into a spreadsheet. Expert researchers in each order verified these data. ICMBio provided the current geographic distribution of each species. For the analysis, the six collections of MapBiomas' land use map were employed. The shapefile of each species' distribution and the design of the LTs were overlaid to determine the species richness. A six-kilometer margin was planned for each LT. As a result, we chose four LTs: Oriximiná (LT1), Xingu (LT2), Tucuruí (LT3), and Manaus-Boa Vista (LT4) (LT4). 178 species were recognized in the initial study, distributed among five orders: five (Carnivora), 27 (Didelphimorpha), six (Pilosa), 91 (Primates), and 50 (Rodentia). Expert confirmation of the distribution and habitat utilization of this species list was done. LT’s richness was 38 species (LT1), 35 (LT2), 29 (LT3), and 47 (LT4) (LT4). LT1 therefore had the greatest richness, whereas LT3 had the least. The most threatened species were found in LT4 (9), then in LT3 (8), and finally in LT1 and LT2 (4). With LT installation, functional connectivity decreased across all LTs examined. LT1 reduced the average size of the connected pieces by 1.2%, LT2 by 0.9%, LT3 by 0.7%, and LT4 by 0.8%. For species with a limited geographic range, LTs will further divide their range, which may increase the process of population decline. Therefore, it is advised that this study be included in linear project EIAs.