Management of the diatom monitoring networks in France

An overview is presented of the development of a biological diatom index(IBD) as one of the means for those managing water quality in France toimprove knowledge about the biological quality of watercourses. Thedecision to make this index applicable to the whole French hydrographical,network, and in particular the National Basin Network, was agreed by theAgences de l'Eau and Cemagref in 1994 and led to the first version in1995. The regular update of software for calculation of indices based onthe IBD and the existence of a users' network have led to numerouspractical applications. Moreover, the Agences de l'Eau have since 1996run application programmes on the National Basin Network, in this waycompleting the initial set of data. Re-examination of the complete set ofdata at the end of 1998 and tests on different calculation options of theIBD led to a third version of the index, which became the standard in June2000. Various steps were taken by the Agences de l'Eau, Cemagref andother partners so that the IBD could be implemented rapidly for thesurveillance networks. These include production of the determination keyand specific IBD index calculation tools, training programmes and severalprojects related to long-term storage of information, such as the creationof a collection of samples and slides and a national database for theinventories. These activities are supervised by a Group of Scientific Interestof Diatoms of Continental Waters, which has, since its creation, managedan IBD intercomparison exercise with the Association des Diatomistes deLangue Francaise. These initiatives have led to the introduction of theIBD in the Hydrobiology Accreditation Programme of the ComiteFrancais d'Accreditation (COFRAC).