Echantillonnage des sites de référence DCE pour les paramètres "faune invertébrée benthique" et "végétation" - District hydrographique Adour-Garonne

Directive 2000/60/CE (Directive Cadre sur l'Eau - DCE) establishes a new framework for a community policy in the field of water. It calls for result, namely achieving, by the end of 2015, good ecological and chemical state of underground and surface water, including coastal and transition (estuary) water. In order to evaluate the ecological state of a mass of water (ME), the DCE directive introduces the notion of "deviation" from a benchmark situation. The reference values, that can be considered as the benchmark level for a very good ecological state, have to be established according to type of ME and per biological quality element (phytoplankton, diatoms, macrophytes, macro-invertebrates and fishes) To do this, a network of reference sites has been set up, according to type of ME and per quality element. Its importance is fundamental as the biological quality evaluation tools will be calibrated on the results obtained during this reference monitoring. In the Adour-Garonne district, which stretches from the Pertuis charentais to the Bidassoa estuary (Spanish border), two reference sites have been selected: the first site, located on the mass of water "Arcachon amont" (upstream Arcachon) (FRFC06 type C07), for the benthic macrofauna and eelgrass bed (Zostera noltii) quality elements and the second site, located on the mass of water "Pointe d'Arcachon/Ondres" (FRFC08 type C06), for the benthic macrofauna.