Relação das variações climáticas regionais com assembleias de vertebrados na Amazônia: perspectivas do monitoramento realizado por pesquisadores indígenas na bacia do rio Negro

Abstract

One of the most debated topics nowadays is climate change and its consequences for humanity and biodiversity. Climate change can alter the functioning of ecosystems by affecting the abundance and occurrence of organisms. The possibility of some groups of animal species in the Rio Negro basin being affected by climate change, with direct consequences for the hunting, fishing, and agriculture activities of indigenous and traditional peoples, as well as for the balance of local ecosystems, motivated the development of this study. The main objective was to investigate, through data collected by local indigenous residents, how climatic variations (precipitation and river level) and fire occurrences are related to the occurrence of species of turtles, birds, and mammals in the Rio Negro basin. For this purpose, we used data collected by the Indigenous Environmental Management Agents from 2017 to 2021, as well as data on precipitation, river level, and fire occurrences for the same period. The recorded species were identified and grouped according to their functional groups based on their diet. We used mixed-effects linear models to assess the slope of linear regressions to estimate the relationship between the functional groups and the predictor variables. A total of 78 species were identified, distributed across 39 families, and grouped into 5 functional groups. Among these taxa, birds stood out, having the highest number of records, and being observed in all studied regions. We found a positive relationship between the functional group of carnivorous birds and the herbivorous and frugivorous mammal groups with the precipitation index, indicating that more records of these groups occurred during the rainier months. The Chelonians groups did not show a significant relationship with any of the predictor variables used. This finding suggests that changes in rainfall patterns can affect the abundance of some groups, leading to imbalances in the ecosystem if these changes occur more frequently and at accelerated rates. This study indicates that even regions still relatively unaffected by deforestation are subject to the effects of anthropogenic climate change, which act at accelerated rates and temporal patterns. Therefore, long-term monitoring is essential to better understand the relationship between predictor variables and the richness of functional groups and to identify possible patterns that can help local populations cope with the challenges imposed by global climate change.