Development of tools for ecological quality assessment in the Polish marine areas according to the Water Framework Directive. Part IV — preliminary assessment

A set of classification methods was developed for the Polish coastal and transitional waters regarding the biological quality elements — phytoplankton, macrophytes and macroinvertebrates as required by the EU Water Framework Directive. Mean summer chlorophyll-a and total summer biomass of phytoplankton were proposed as indicators in the phytoplankton assessment. Macrophytes were assessed by the Macrophyte Quality Assessment Index, including biomass and percent bottom coverage of the selected taxa. Macroinvertebrate assessment was based on a biotic index comprising abundance, dominance structure, taxonomical richness and species sensitivity/tolerance to eutrophication. A preliminary assessment of the ecological status revealed that the coastal and transitional waters failed to reach a ‘good’ ecological status.