"Marsh" database: characterization of the state of the necton in two depolderized zones of the Gironde estuary

In the Gironde estuary, two accidentally de-polderized marshes have been the subject of biological monitoring (necton) since 2008: the Marais de Mortagne-sur-Gironde and the northern part of Île Nouvelle. The Mortagne-sur-Gironde marsh is located in the mesohalin sector of the Gironde estuary. With an area of 191 hectares, the marsh was dammed in 1966 and cultivated for more than 30 years. Its protective dike gave way during the December 1999 storm. Ile Nouvelle is located in the Oligaline Sector of the Gironde Estuary. The northern part of the island - an area of 141 hectares - has been depolderized during the passage of storm Xynthia in 2010, following the opening of a breach.<br> Biological monitoring (necton) was carried out in the Gironde estuary over the period 2008-2016 to test the hypothesis that the depoldisation of the estuarine shorelines makes it possible to recreate nursery and feeding areas for fish and fish. estuarine and coastal macrocrustaceans. This work was carried out by the National Institute for Research in Science and Technology for the Environment and Agriculture (Irstea), in partnership with the Conservatoire du Littoral, the Gironde Departmental Council and the Regional Council for Natural Areas ( CREN) of Poitou-Charentes.<br> The "Marsh" database includes all the surveys carried out throughout the study, between 2008 and 2016, and in particular samplings carried out within the necton.在吉伦特河口，两处经意外脱圩的滨海沼泽自2008年起便开展了自游生物（necton）生物学监测，监测对象分别为吉伦特河畔莫尔塔涅沼泽（Marais de Mortagne-sur-Gironde）与新岛（Île Nouvelle）北部区域。吉伦特河畔莫尔塔涅沼泽地处吉伦特河口的中盐度（mesohalin）带，该沼泽面积达191公顷，1966年筑坝围垦并被垦殖逾30年，其防护堤在1999年12月的风暴中溃决。新岛则位于吉伦特河口的寡盐度（Oligaline）带，该岛北部区域面积141公顷，在2010年文西亚（Xynthia）风暴过境时因溃坝而完成脱圩修复。<br>2008年至2016年间，研究团队在吉伦特河口开展自游生物生物学监测，以验证"河口岸线脱圩可重建鱼类、河口及沿海大型甲壳类的育幼与索饵生境"这一科研假说。本项研究由环境与农业科学技术国家研究所（Irstea）牵头实施，合作方包括法国滨海保护协会（Conservatoire du Littoral）、吉伦特省议会以及普瓦图-夏朗德大区自然区域委员会（CREN）。<br>"Marsh"数据库收录了2008年至2016年整个研究周期内开展的全部调查数据，尤其涵盖自游生物采样相关的全部内容。