Étude des secteurs du Croisic et de Pen-Bé : estimation des apports continentaux et évaluation des stocks conchylicoles

Ifremer, Nantes University and the township community CAP Atlantique have joined their skills to try to better understand how two key conchological areas in the shore economy of the Pays de la Loire area develop, especially since, environmentally, little is known about them, and because they face recurrent issues on the zootechnic level. This programme encompasses two main topics: assessment of environmental inputs (catchments areas input, contaminants evolution in the area, and impact on the conchological zones) and a study of the conchological culture (growth, mortality, analysis of the stocks). Concomitantly, operational tools (hydrodynamic and flux transfer models, databases, SIG) are developed to improve local management of the sites and information delivery to users. The Pays de la Loire region supported this 240 k? (not including labour costs) project from 2002 to 2004. Conclusions have been drawn on the basis of the final results (Scientific and Technological Body, June 2005): - Innovative development of operational tools: modelling of the inputs through the catchment areas with a coupling SIG/ agro-pedological model (subject of a doctoral basis presented in May 2005), hydrodynamic modelling of the pollutant evolution, and first attempt to couple a land model and a marine model; - Creation of a database on water quality in the peninsula of Guerande that helps improving information delivery to users and exchanging data with the other data producers; - Creation of a protocol for flow follow-up and first assessment of phytosanitary product impacts. - First assessment of conchological culture, with possible definition of cultural methods according to the different area potentialities; - contribution to research structuring in the Pays de la Loire Region for a further collaboration between Ifremer and Nantes University on the « Sea, estuary and shore » programme...