Assessment Criteria and Ecological Classification of Polish Lakes and Rivers: Limitations and Current State

Abstract

An assessment of the ecological status or potential is based mainly on examination of the aquatic ecosystem functioning regarding organisms that inhabit them. These include phytoplankton, macrophytes and phytobenthos, benthic macroinvertebrates and ichthyofauna. However, hydromorphological and physicochemical elements are also of importance as supporting biological features. The results of ecological status assessment, made for data obtained from the Polish-Norwegian project “DeWELopment”, indicate that ichthyofauna and the hydromorphological elements in rivers as well as phytoplankton and benthic macroinvertebrates in lakes were decided primarily on final ecological classification. According to the accepted in Poland integration of partial assessments based on the one out all out principle, the lakes in the Wel River catchment were classified as not meeting the WFD-required at least good ecological status, and rivers, in turn, only a half of them. The latest analysis of the risk of a failure to achieve the environmental objectives (i.e. at least good ecological status/potential of water bodies in the two largest catchment areas in Poland) has shown that 74% of water bodies in the Vistula River Basin and 67% of water bodies in the Oder River Basin have been classified as being in danger of failing to achieve these objectives. Moreover, assessments have not been made for approx. 30% of water bodies covered by the assessment in both of these catchment areas.