Impactos da implantação de uma PCH no Rio São Francisco Verdadeiro: alterações na estrutura funcional e simplificação biótica da comunidade de macroinvertebrados bentônicos

Abstract

Habitat alteration resulting from anthropogenic disturbances is a significant concern in contemporary ecology. In this context, benthic organisms are extremely recognized as water bioindicators and efficient tools for analyzing anthropogenic impacts on aquatic ecosystems. First of all, considering the processes of population growth, driven by agricultural expansion combined with climate change, the investigation of the functional characteristics of these organisms is crucial. This study investigated the effects of implementing a Small Hydroelectric Power Plant (SHP) on a river, analyzing the periods before and after its construction. We used spatial and temporal analyzes to assess how the benthic macroinvertebrate community responded to new ecological selective cues, focusing on our functional trait indices and applying a redundancy analysis (RDA) on functional trait abundances. The results demonstrate that the relative composition of functional traits in the macroinvertebrate community was beneficially altered by PCH, reducing the diversity of traits mainly in the directly affected region. These results corroborate our hypotheses of biotic simplification, with a reduction in biological diversity, alteration and reduction in functional characteristics resulting from the construction of the dam, providing substantial evidence of negative impacts on the functional diversity of benthic macroinvertebrates.