Níveis de resiliência ecológica de quelônios continentais da Amazônia Legal

Abstract

Continental chelonians, especially the Amazonian ones, are among the groups which most demand new researches and integrated studies, whether in the systematic or ecological scope, whose knowledge helps in their preservation, as well as ecosystem and environmental services performed. Therefore, the present work aims to analyze the levels of climate resilience of continental species in the Legal Amazon, via correlation/interdisciplinarity between climate models and anthropogenic pressure with geochemical proxies, more specifically isotopes of carbon and nitrogen, with results that enable interpretations more precise information on climatic and isotopic refuges (isoscapes), as well as additional information related to trophic chains. Until then, climate models were developed, with simulations referring to Representative Concentration Pathways (or RCPs) and Shared Socioeconomic Pathways (or SSPs) for ten chelonian species, given their sufficient number of recorded observations and coordinates: Chelus fimbriata; Mesoclemmys gibba; Phrynops geoffroanus; Platemys platycephala; Podocnemis expands; Podocnemis unifilis; Rhinoclemmys punctularia; Kinosternon scorpioides, Chelonioidis carbonaria and Chelonoidis denticulata. Such coordinates were intercrossed with four environmental variables from the Worldclim digital platform, selected according level of influence on the species distribution, reported in the literature, as well as reduced inter-correlation. These procedures were performed by Rstudio software, through the Biomod2 package, which reunites a set of algorithms whose mathematics allowed the development of rasters, with informations of climatic suitability inherent to each species. So far, P. expansa, P. unifilis and, above all, Ch. denticulata, are considered the most threatened of population reduction, while Ph. geoffroannus and K. scorpioides projections have shown less climate vulnerability. This parameter tends to be maintained in future circumstances, even with anthropogenic interference. The other species also present certain levels of vulnerability, which are more limited when compared to Ch. denticulata e P. unifilis levels. Confrontation of projections with isotopic signatures from nitrogen and carbon, collected from bone tissues of specimens deposited at the Instituto Nacional de Pesquisas Amazônicas (INPA, Manaus/AM) and Museu Paraense Emílio Goeldi (MPEG, Belém /PA). with climate models and anthropogenic influence, tend to reinforce politics to preserve species and their niches, as a strategy to maintain regional biodiversity.