BENTHIC MACROINVERTEBRATES IN SERRA DO CIPÓ (MG, BRAZIL) 239 BIODIVERSITY ASSESSMENT OF BENTHIC MACROINVERTEBRATES IN ALTITUDINAL LOTIC

(With 2 figures) Five lotic systems of Serra do Cipó, south-east Brazil, were investigated in order to assess the existing diversity of benthic macroinvertebrates, habitats-microhabitats, and the available trophic resources. For each river it was analysed the communities of benthic macroinvertebrates and the com-position of some taxonomic groups (Plecoptera, Ephemeroptera, Trichoptera and Diptera Chirono-midae): the community with Bivalvia Sphaeriidae, Oligochaeta and Ephemeroptera Baetidae (being supposed a closed relation Bivalvia-Oligochaeta based on the process of bioturbation and enrichment of sediment in organic matter) in Tanque River; the macrofauna associated to aquatic macrophytes from rivers Peixe and Preto do Itambé reflecting the reaction of the ecosystems versus the quanti-ties of nutrients which originate from the farmlands; the lithoreophilic communities of Cipó River; the community depending on deposits of leaves and filamentous algae in Congonhas Stream; the very rich community of the moss clumps in the Indaiá Stream. A proposal for biological zonation of Cipó River and some comments about the importance of the analysed benthic macroinvertebrates in the biological production of the aquatic communities were done