Effect of mining on the EPT (Ephemeroptera, Plecoptera and Trichoptera) assemblage of Amazonian streams based on their environmental specificity

The way species respond to environmental changes depends on several factors, but mainly on their niche breadth in the face of habitat variability and changes. Our study evaluated, over a six-year period, how the abundance and richness of generalist and specialist genera of Ephemeroptera, Plecoptera and Trichoptera (EPT) respond to mining activities in the Carajás National Forest, Pará state, Brazil. We hypothesized that the abundance and richness of specialist genera would be lower in streams impacted by mining. We collected 49,822 individuals, distributed in 31 genera classified as specialists and 28 as generalists. Using Generalized Linear Mixed Models (GLMM) we found that there was a negative effect of mining on the estimated richness of specialists and, contrary to what we expected, there was a positive effect of mining on the abundance of specialists. On the other hand, the generalists negatively responded to the mining in the estimated richness and abundance. Specialists in streams affected by mining may increase their abundances due to habitat homogenization. Therefore, partitioning the assemblage into generalist and specialist groups has important applications in monitoring and better understanding assemblage patterns and how they are affected by anthropogenic effects, specifically mining.