Diversidade funcional e riqueza de táxons de macroinvertebrados em córregos na região neotropical

Abstract

This work was divided into two chapters, independent of each other, which are characterized by the approach used in common and the vast region in which are inserted the study areas (Neotropical region), as well as the main objective, which aims to contribute to maintenance of the environment through biomonitoring, suggesting the functional diversity in addition to the commonly used indices. In the first chapter, we evaluated the relationship between insect functional diversity and species richness in streams in the Atlantic Forest region, seeking to understand the role of local, landscape and spatial variables in explaining distributional patterns. We determine how much of the variation in different measures of functional diversity is explained by predictor sets using partitioning the variation method , based on multiple regression analysis. Our study highlights two main patterns: i) functional diversity is strongly related to taxa diversity of aquatic insects along the gradient of integrity of Atlantic Forest streams and, ii) functional diversity is better explained by a set of variables. Our results indicate low redundancy among the functional traits of the species along the environmental gradient, and add more information about the harmful effects on biodiversity in the Atlantic Forest caused by changes in the landscape, indicating that these effects also influence the functional organization. In the second chapter we analyzed how the functional diversity varies under different environmental integrity, seeking which functional indices that discriminate environmental gradients in Bodoquena Plateau and the implications of the results for metrics selection that are potentially applicable to biomonitoring in the region.We applied the habitat integrity index (HII) to categorize different land uses, riparian zone integrity, habitat structure and forest cover percentage on sampling sites. As functional indices (FI), we used functional richness (Fric), functional dispersion (FDis), functional evenness (FEve) and functional divergence (FDiv). The results did not show a linear relationship with values of environmental integrity, streams with high values of HII showed low functional richness, but high functional divergence and functional dispersion. To reduce the uncertainties and possible artifacts related to potential lack of relationship between functional indices and HII, we need to evaluate a wider range of environmental gradients and refine the functional categorization of aquatic insects in the tropics.