Application of water framework directive in Hungary: development of biological classification systems.

The classification according to the Water Framework Directive (WFD) includes numerous challenges in contrast with the previously applied water qualification standards. The most important element of the ecological status, the biological one, is based on five groups of living organisms: phytoplankton, phytobenthon, macrophytes, macro-invertebrates and fish. The results of a three-year research project financed by the Ministry of Environment and Water (MoEW) and the Hungarian Academy of Sciences (HAS) are reported in this work. The objective of the project was the elaboration of a proposal for biological classification according to the WFD for the related groups of living organisms. In the course of the project the biological characteristics to be measured were selected for each of the above listed groups which served as the basic data for Biological Quality Elements (BQEs). In the BQEs we estimated the type-specific reference values for most of the Hungarian surface water types. Then we created the structure of the qualification system for these groups, including specification of class boundaries between the five classes for the Environmental Quality Ratio (EQR) values on the basis of expert estimation. A Non-Taxonomic Periphyton Index (NTPI, not included in the WFD) was also developed and tested for qualification. The elaborated classification systems were tested on the basis of existing scarce data for numerous Hungarian water types.