A influência das mudanças climáticas na distribuição de áreas adequadas para mamíferos na ecorregião da Savana Uruguaia

Abstract

South America has a large number of species with restricted distribution that depend on specific habitats and niches. However, climate changes drastically alter precipitation and temperature patterns, which can lead to modifications or even the disappearance of these habitats, thus threatening the realization of these niches. This work aims to analyze the impact of climate change on the distribution of suitable areas for threatened mammals and/or with species with restricted distribution in the Uruguayan Savannas ecoregion, which includes the grasslands of Rio Grande do Sul, the southernmost state of Brazil, and Uruguay. Ecological niche models were constructed to identify suitable areas for 67 species of mammals using data from Worldclim for the current weather and for the year 2070, using three modeling algorithms, Support Vector Machines (SVM), Random Forest (RF) and MaxEnt and three models of global circulation, CCSM4 (Community Climate System Model), HadGEM2-ES (Hadley Global Environment Model 2) e MIROC-ESM-CHEM (Model for Interdisciplinary Research on Climate), for RCP 4.5 and RCP 8.5 scenarios. The models point to a reorganization of the mammal fauna in the Uruguayan Savanna ecoregion. It is expected to have a decrease in the number of grassland species and an increase in the richness of forest, generalist and semi-aquatic species within both scenarios in the Uruguayan Savanna ecoregion, indicating a transition from the current fauna, predominantly adapted to grasslands, to a more tropical / forest adapted fauna. This reorganization of fauna occurs mainly in the transition zone between the Atlantic Forest biome and the Uruguayan Savanna ecoregion, that is, in the northern part of this ecoregion.