DATA ON BIOLOGICAL ASSESSMENT OF WATER QUALITY IN ERZENI RIVER USING AS BIO ? INDICATORS DEFFERENT GROUPS OF BENTHIC INVERTEBRATES

Ecological water quality is closely related to the biological communities’ conditions. Benthic macroinvertebrates are determinate as crucial elements and have a great importance in biological assessment of water quality (Water Framework Directive - WFD). . Ecosystem biological elements often are influenced by human activity, which acts by modifying or adapting their composition and structure (Simboura, 2008). Erzeni River flows in central Albania in an area with sandy ? clay deposits (Saraçi R., 1996). So the geographical position and geologic composition of river basin have a specific study importance.Our study aims to give data on biological assessment of Erzeni River water quality based on insect and invertebrate fauna. From the data analyses is important to mention the presence of benthic sensitive organisms (Environmental Protection Agency- USA) in two stations. Also were present two other groups, benthic invertebrates with a medium tolerance toward pollution and tolerant taxons. The values of EPT (Ephemeroptera, Plecoptera and Trichoptera) and Biotic Index have classified Erzeni River water as good - medium quality. Also based on this biological assessment during three successive seasons we can conclude that the water quality of Erzeni River shows differences between the study stations.