Assemblage of oligochaetes in mesohabitats of streams with different land uses in Minas Gerais, Brazil.

The different environmental conditions resulting from the mesohabitats and land uses around streams can interfere in the structure and composition of the oligochaete fauna, widely used as indicators of aquatic ecosystems. The objective of the present study was to evaluate and compare the oligochaete fauna found in mesohabitats of pools and riffles in streams with different land uses in their proximity (forested, urban and pasture). A sampling of fauna and environmental parameters was carried out in nine streams belonging to the Ribeirão Marmelos sub-basin, Minas Gerais. A significant difference in the oligochaete fauna was found in the different mesohabitats and land uses. Conductivity, width, and depth were important variables in the separation between pools and riffles. Aulophorus furcatus was the species associated with urban environments, Pristina jenkinae to riffles and Opistocysta funiculus, Limnodrilus hoffmeisteri, and juvenile Tubificinae were linked to pools. The results found may contribute to understanding the relationship between the structure and composition of the oligochaete fauna, the mesohabitats and land use. [ABSTRACT FROM AUTHOR]