A urbanização influencia no processo de colonização de assembleias de Chironomidae?

Abstract

Research on the colonization of aquatic insects points to human impacts as determinants for the structuring of this community. The present study aims to analyze the colonization process of the Chironomidae assembly in streams with different degrees of anthropic impacts. In nine streams located in the municipality of Poços de Caldas (MG) 12 traps were placed, consisting of polyethylene bottles. The streams were classified according to their environmental integrity in Natural Preseved (PN), Urban Preserved (PU) and Urban Impact (UI). In each bottle, 100g of Typha domingensis was placed as substrate. Fortnightly, three bottles were removed from each stream, for a total period of 60 days. In the laboratory, the material was sorted and the Chironomidae larvae were assembled in slides for identification down to the genus level. Then, after removing the biological variables, a Non-Multidimensional Scaling analysis was performed Metric (NMDS), using a Bray-Curtis dissimilarity matrix. It was noted a correspondence between the measured abiotic variables of each environment with the groups found in the family Chironomidae. This relationship between environments and genus found showed that urbanization causes changes in the groups of