Confronto tra indici di qualità basati sul fitoplancton per l'implementazione della

The Water Framework Directive (2000/60/CE) requires that the ecological quality of water bodies is estimated by comparing a series of biotic indicators to a reference optimum condition. To establish which already developed indices fit best the estimate of the trophic status of Italian lakes, two indices were applied to 11 natural lakes in the sub-alpine area and 8 reservoirs in Sardinia: Catalàn Index and Brettum Index. The results show a good correspondence of the Brettum Index for the lakes of the sub-alpine ecoregion only; none of the two indices seems to be right to assess the ecological quality of Sardinian reservoirs.