XVI International Botanical Congess

Diatom-based methods used in Europe for monitoring rivers are reviewed and the results of studies briefly presented. The French experience is described including the integration of the diatoms into the biological part of the System for Watercourse Quality Evaluation. This integration led to the elaboration of tools like the Biological Diatom Index, programs for calculation, identification keys and standards. A Scientific Interest Groupcreated in 1999 aims the help for the training of biologists, a diatom quality chart and the creation of national reference databases. The proposal of the European framework directive Water Resources led to the creation of a Macrophytes and benthic algae group, which works now for standards for the sampling of diatoms for biomonitoring and for an intercalibration exercise.