Application of diatom water quality indices in influenced and non-influenced sites of Slovak rivers (Central Europe)
Hlúbiková, Dasa; Hindáková, Alica; Haviar, Matús; Miettinen, Juha
The applicability of 13 diatom indices included in Omnidia software to an ecological status assessment of Slovak rivers was examined. In all, 428 samples were analysed and included in the trial data-set. Samples were collected in 2003 and 2004 at 158 anthropogenically influenced sites, representing differing degrees of human impact (313 samples) and at 58 reference sites with uninfluenced conditions (115 samples). The suitability of the indices was assessed by testing their ability to differentiate between non-influenced and anthropogenically influenced conditions by means of correspondence of the indices with pre-defined water quality classes and correlations with selected environmental variables (covering land use, water chemistry and hydromorphological changes). The results of the statistical analyses indicated that CEE (Descy & Coste 1991), IPS (Cemagref 1982) and EPI-D (Dell'Uomo et al. 1999) are among the most suitable indices for the purposes of ecological status evaluation of Slovak rivers, as required by the Water Framework Directive.