Padrões estruturais de Trichoptera em riachos de altitude na Mata Atlântica

Abstract

Anthropogenic impacts on the Atlantic Forest can affect the diversity and composition of aquatic insects. Isolation factors in regions of high-altitude, such as mountain ranges, climatic fluctuations and dominant vegetation type contribute to this dynamics. The objective of the research was to analyze the distribution and importance of environmental and spatial factors for the community structure of Trichoptera larvae. Functional and taxonomic characteristics were compared. A total of 823 organisms were distributed into nine families and 18 genera. The samples were collected in 34 headwaters streams in 8 watersheds of plateau “Poços de Caldas”, Brazil in in the years of 2013 and 2015, in the months of May and August. The most abundant genera foun were Notalina and Phylloicus. Pollution in the watercourse and the influence of Eucalyptus caused a drastic reduction in the richness and diversity of the animals. The same effect was observed in the urban streams, especially those with low percentage of native forest. Rural roads were not related to the high content of Dissolved Total Solids. The partitioning of the variance indicated that Functional Feeding Groups were the most sensitive to the environmental factors, which prevailed over the spatial ones. The low number of genera show the importance of preservation as well as the rare genera Contulma and Anastomoneura