seanoe:102639 Sabine Schmidt EPOC, Univ. Bordeaux, CNRS, Bordeaux INP, UMR 5805, F-33600 Pessac, France 2024-10-16 ISO 19115:2003/19139 1.0 Depth profiles of selected radionuclides in marine sediments of three macrotidal saltmarshes of the French Atlantic coast 2024 2024-10-16 Sabine Schmidt, Benjamin Amann (2024). Depth profiles of selected radionuclides in marine sediments of three macrotidal saltmarshes of the French Atlantic coast. SEANOE. https://doi.org/10.17882/102639 Three saltmarshes, Aiguillon, Brouage, Fier d'Ars, located in the Pertuis-Charentais Sea along the south-west coast of France, were studied to evaluate their sediment and mass accumulation rates (SAR; MAR) based on 210Pb and 137Cs profiles in sediments. Coastal saltmarshes play indeed an essential role in providing services such as coastal protection and supporting biodiversity. Saltmarshes are also critical environments for the accumulation of sedimentary organic carbon (blue carbon). However, the number of studies on saltmarshes remains underrepresented compared to studies on mangroves and seagrass. This work is a contribution to the effort to document sediment and mass accumulation rates of saltmarshes.A total of 16 1m sediment cores were collected in the three saltmarshes (Aiguillon, Brouage, Fier d'Ars) in 2021 and 2022 using an Eijkelkamp stainless steel peat sampler. Each sediment core was sampled every 1 cm from the top to the bottom of the core. The sediment layers were used to determine dry bulk density and selected radioisotope activities (210Pb, 226Ra, 137Cs, 228Th, 137Cs). Combining excess 210Pb and 137Cs has allowed to establish a reliable chronology of sediment deposition on a multidecadal timescale. This research was supported by the PAMPAS project (ANR-18-CE32 -0006-01) and the La Rochelle Territoire Zero Carbone project (LRTZC, Carbon Bleu Axe2 OPE-2021-0376, OPE-2021-0496). Sabine Schmidt EPOC, Univ. Bordeaux, CNRS, Bordeaux INP, UMR 5805, F-33600 Pessac, France Benjamin Amann LIENSs, La Rochelle Université, UMR 7266 CNRS, 17000, La Rochelle, France SEANOE https://www.seanoe.org/data/00915/102639/illustration.gif Core sampling in the Brouage saltmarshes in July 2021 Saltmarsh 210Pb Sediment Pertuis-Charentais Sea 226Ra Bay of Biscay 228Th Sedimentation accumulation rate 137Cs Mass accumulation rate Dry buld density Marine geology Trace elements and their isotopes ODATIS aggregation parameters and Essential Variable names 2025-07-29 geonetwork.thesaurus.external.theme.NVS.OD1 Marine geology SeaDataNet Parameter Disciplines 2025-07-29 geonetwork.thesaurus.external.parameter.NVS.P08 /Observational data/in-situ Type de jeux de donnée ODATIS 2024-10-15 geonetwork.thesaurus.local.theme.type_jeux_donnee CC-BY (Creative Commons - Attribution) Multi-annual and multi-decadal evolution of sediment accretion in a saltmarsh of the French Atlantic coast: Implications for carbon sequestration 2023 Elsevier BV Amann B. Chaumillon E. Schmidt S. Olivier L. Jupin J. Perello M.C. Walsh J.P. 10.1016/j.ecss.2023.108467 oceans -1.6 -0.9 45.7 46.5 2021 2022 CSV https://www.seanoe.org/data/00915/102639/ WWW:DOWNLOAD-1.0-link--download Quality controlled data Profiles of dry bulk density and selected radionuclides in Aiguillon sediment cores [RESTRICTED] - 78 KB https://www.seanoe.org/data/00915/102639/ WWW:DOWNLOAD-1.0-link--download Quality controlled data Profiles of dry bulk density and selected radionuclides in Brouage sediment cores [RESTRICTED] - 52 KB https://www.seanoe.org/data/00915/102639/ WWW:DOWNLOAD-1.0-link--download Quality controlled data Profiles of dry bulk density and selected radionuclides in Fier d'Ars sediment cores [RESTRICTED] - 53 KB https://doi.org/10.17882/102639 WWW:LINK-1.0-http--metadata-URL DOI of the product https://www.seanoe.org/data/00915/102639/ rel-canonical Seanoe Dry bulk density (DBD) was determined at LIENS. For this purpose, the water content was determined by weighing each sediment sample before and after drying at 60°C, and the dry bulk density was then calculated, assuming a mineral density of 2.65 g/cm. The radionuclide determinations were carried out at EPOC. The activities of 210Pb, 226Ra, 228TH and 137CS were measured with a high efficiency broad energy gamma detector equipped with a Cryo-Cycle II (@Mirion). The gamma detector was calibrated with IAEA certified materials (RGU-1; RTh-1). Errors on activities were based on standard deviation counting statistics.