The use and limits of various methods of sampling and interpretation of benthic macro-invertebrates

This paper attempts to provide an overview of the present state of the art of biological sampling of aquatic benthic macro-invertebrates as reflected in the international standard methods of the International Standards Organisation (ISO) and the European Standards Organisation (CEN). Also of importance are guideline standards which assist in the standardisation of the interpretation and presentation of the biological data. The importance of standardising methods of sampling aquatic habitats has been recently recognised by the European Union by the inclusion of these standards as a mandatory requirement within the Framework Directive (2000/60 EC European Parliament and Council) for the protection of inland surface waters. Adherence to these standards of sampling by member countries ensures that the biological survey data is comparable throughout the Union and can be assessed as an improvement, deterioration or stable biological quality at agreed survey sites.