THE ECOLOGICAL STATUS OF EUROPEAN RIVERS: EVALUATION AND INTERCALIBRATION OF ASSESSMENT METHODS

In this special issue we present the major results of the EU funded research project STAR (Standardisation of River Classifications: Framework method for calibrating different biological survey results against ecological quality classifications to be developed for the Water Framework Directive; contract number EVK1-CT-2001-00089). The aims of STAR were to develop methodologies, tools and background information to assess rivers throughout Europe using diatoms, macrophytes, invertebrates, fish and hydromorphological features. The project's research questions and structure are described in detail by Furse et al. (2006). STAR has generated results over a wide spectrum of topics, ranging from river typologies and new methodologies for assessing the condition of rivers using macrophytes to the uncertainty of assessment approaches. This special issue is structured to reflect the broad scope of the project and is sub-divided into seven sections. Each contains up to six papers describing specific results and each is introduced by a summary paper reviewing the main findings of the papers in the section. Individually, these sections are: - Stream and river typologies - Linking organism groups - Macrophytes and diatoms - Hydromorphology - Tools for assessing European streams with macroinvertebrates - Intercalibration and comparison - Errors and uncertainty in bio-assessment methods