Macrozoobenthos in an altitudinal gradient in North Patagonian Cautín River (Araucanía Region, Chile)

Abstract The Cautín River is closely related with the economic development of Temuco city, (38°S; Chile). Existing knowledge limited to information about its biological characteristics as a reference for evaluation and assessment water quality. object this study was develop taxonomic characterisation benthic macroinvertebrates along main course River, community structure using correlation analysis between parameters. To carry out research, macroinvertebrate studied in 10 sampling sites distributed river. samples were taken summer (1997 2000), when optimal hydrological conditions existed. Analysis showed that fauna composed 56 taxa, dominant group being insects 48 taxa. Three sectors recognised River: high, middle low. Each sector has restricted-distribution species, while other species are widely These distribution patterns seem be influenced by dissolved oxygen concentration, temperature, altitudinal anthropo-cultural activity, present at every site. Finally, research provides first approach biology River. Further studies could planned on basis investigate quality indicators based communities.