Functional diversity of mayflies (Ephemeroptera, Insecta) in streams in mining areas located in the Eastern Amazon

The effects of mining-induced changes on natural environments extend from terrestrial to aquatic ecosystems. Our study aimed to investigate how mining activities affect the functional beta diversity of Ephemeroptera nymphs and select species with specific traits. We tested whether: (a) preserved streams have higher functional beta diversity of Ephemeroptera than altered streams, and (b) environmental variation is the main predictor of functional beta diversity. This study was conducted in an environmental gradient of mining activities in 24 streams in the eastern Amazon. Our main results showed that environments altered by mining activities had higher iron and turbidity values, and a broader environmental variation. In addition, we showed that the functional beta diversity of mayflies was higher in streams altered by mining. The results indicated that there was greater dissimilarity of species between altered areas, but the groups of species in these areas presented higher importance of the nestedness component and loss of traits, indicating that subgroups of Ephemeroptera with similar functional traits are formed in these locations. We conclude that mining impacts can be observed at the level of functional traits of Ephemeroptera, especially in the (beta) variation among communities in environments under different environmental impacts.