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.

Bivalves carbon and nitrogen elemental and isotopic ratios (δ13C, δ15N, C and N%, C:N) times series (1981-2021) from 33 sites in France. Bivalve species are the Pacific oyster Crassostrea gigas, and the mussels Mytilus edulis and Mytilus galloprovincialis. This extensive dataset offers a comprehensive view spanning multiple decades and ecosystems, allowing to track how coastal ecosystems and marine species record changing climate, physical-chemical environments and organic matter cycles. This dataset may also be used to study bivalve physiology. Additionally, these data are crucial for establishing isotope baselines for studying food webs. Ultimately, this data set provide valuable information for more effective ecosystem conservation and management strategies in our rapidly changing world.

The SAPERCHAIS program (Suivi des Apports marins et terrigènes dans la mer des PERtuis CHarentAIS) was developed to monitor environmental fluctuations in the Pertuis Charentais Sea by an hydrological watchfulness. Seven stations, representatives of terrigenous or marine inputs, have been followed from 2011 to 2014. From north to south, the main four rivers of the Pertuis, Le Lay, La Sèvre, Charente and Seudre, and the three maritime inputs of each strait, Breton, Antioche and Maumusson. At each station, temperature and salinity were recorded in situ, just below the surface, with a high frequency resolution (10 minutes) . This work was supported by grants from Région Poitou-Charentes and European Regional Development Fund to the Ifremer "Developpement Durable de la Pêche et de la Conchyliculture" project.

############# # Data description # #############   This dataset have been constructed and used for scientific purpose, available in the paper "Detecting the effects of inter-annual and seasonal changes of environmental factors on the the striped red mullet population in the Bay of Biscay" authored by  Kermorvant C., Caill-Milly N., Sous D., Paradinas I., Lissardy M. and Liquet B. and published in Journal of Sea Research. This file is an extraction from the SACROIS fisheries database created by Ifremer (for more information see https://sextant.ifremer.fr/record/3e177f76-96b0-42e2-8007-62210767dc07/) and from the Copernicus database. Biochemestry comes from the product GLOBAL_ANALYSIS_FORECAST_BIO_001_028 (https://resources.marine.copernicus.eu/?option=com_csw&view=details&product_id=GLOBAL_ANALYSIS_FORECAST_BIO_001_028). Temperature and salinity comes from GLOBAL_ANALYSIS_FORECAST_PHY_001_024 product (https://resources.marine.copernicus.eu/?option=com_csw&view=details&product_id=GLOBAL_ANALYSIS_FORECAST_PHY_001_024). As fisheries landing per unit of effort is only available per ICES rectangle and by month, environmental data have been aggregated accordingly. ############### # Colomns description # ############### rectangle - The 6 ICES statistical rectangles used in the study. time_m - Time in months, from the beginning to the end of the study. annee = year mois = month (from 1 to 12) Poids = Weight of red mullet landed valeur = Temps_peche = fishing time Nb_sequence = number of fishing sequences Moy / Med / Var / StD Quartil_1 / Quartil_3 / min / max / CV / IQR = statistical descriptors of landing by rectangle and by month log_cpue = log of Med colomn mean_surface_s = mean of surface salinity by month and by rectangle median_surface_s = median of surface salinity by month and by rectangle mean_surface_t = mean of surface temperature by month and by rectangle median_surface_t = median of surface temperature by month and by rectangle si / zeu /po4 / pyc / o2/ nppv / no3 and nh4 mean and median concentration by rectangle and by month pc3 / pc2 / pc1 - projections of previous biochemestry variables on the three first axes of a PCA

SUCHIMED 2021 is the 10th campaign for monitoring chemical contamination and its evolution in the Mediterranean Sea. It has been designed as a platform supporting various surveillance and research activities, with the main pillar being the RINBIO network, which involves active biosurveillance through mussel caging. Regarding chemical contamination, the main results of this campaign are as follows: In Occitania region: - Chronic presence of DDT for 20 years. - Detection of terrigenous markers (Mn, As) between the mouths of the Aude and Hérault rivers, along with contamination of sediments near Port-La-Nouvelle by HAP and TCE (Pt). In PACA region: - PCB markers detected between the Rhône River and Marseille (in all matrices), originating from multiple sources with no significant changes over the past 20 years. - HAP contamination in sediments of the industrial-port zone in Fos. - Presence of TBT at the Carry-le-Rouet station above ecologically acceptable concentrations (EAC), to be confirmed in the next campaign. - Detection of metallic elements and HAP in sediments near the Marseille urban area, partly in plankton, along with TCE near the Cortiou wastewater treatment plant outfall. - Chronic marking of PCB, HAP, metals (Hg, Pb, Cu, TCE), PBDE, and/or organotin compounds (TBT) in Toulon Bay, showing no significant temporal trend over two decades for the first five compounds. - Detection of Cr, Mn, and Ni in the water column and HAP in sediments near the Var River mouth, with differences in contamination between matrices raising questions about organic matter origin. - Metal (including Pb) and HAP marking in the water column and sediment in Villefranche Bay. Around Corsica: - Strong influence of the island's geological background (i.e., high Cr and Ni content) on obtained concentrations. - Chronic marking of Cu in the water column in the ports of Porto-Vecchio and Bonifacio, stable over time, with HAP, metals (Hg, Pb, Zn), and to a lesser extent, PCB detection in Bonifacio sediment. - Marking of HAP and TCE in the sediment of the Bastia coastline. - Detection of Pb and TCE at the Golo River mouth. - Contamination of the Canari site with metals (Cr and Ni in the water column, Cu in sediment), and notably, confirmed ecotoxicity likely linked to these elements. The 2021 campaign highlighted the feasibility of researching effects on caged mussels using biomarkers. Lysosomal markers, less sensitive to trophic differences, proved to best reflect the general stress state of organisms related to their contamination. The study of trophic transfers appears to confirm the decrease in most metallic elements (Cr, Cu, Fe, Mn, Ni, Pb) and HAP, bioamplification of Hg and PCB, and specific bioaccumulation of certain elements by organisms (e.g., As or Zn by mussels, HAP by plankton). Finally, the campaign revealed the presence of micro and mesoplastics at almost all sampled sites. The measured microplastic values align with concentrations observed in the western Mediterranean, with a trend towards reduction based on available 10-year data.

REPHYTOX dataset includes long-term time series on phycotoxins in marine bivalve molluscs, since 1987, along the whole French coast. The dataset covers results on lipophilic toxins, PSP toxins, ASP toxins, and palytoxins. REPHYTOX was a full part of the REPHY network until 2015. The whole dataset is available.

An observation network was initiated in 2021 in the framework of the CocoriCO2 project to monitore carbonate parameters along the French coastal systems. Six sites were selected along the French Atlantic and Mediterranean coastlines based on their importance in terms of shellfish production and the presence of high- and low-frequency monitoring activities. At each site, autonomous pH sensors were deployed both inside and outside shellfish production areas, next to high-frequency CTD (conductivity-temperature-depth) probes operated through two operating monitoring networks (SNO COAST-HF and Ifremer ECOSCOPA). pH sensors were set to an acquisition rate of 15 min and discrete seawater samples were collected biweekly in order to control the quality of pH data (laboratory spectrophotometric measurements) as well as to measure total alkalinity and dissolved inorganic carbon concentrations for full characterization of the carbonate system. While this network has been up and running for more than two years, the acquired dataset has already revealed important differences in terms of pH variations between monitored sites related to the influence of diverse processes (freshwater inputs, tides, temperature, biological processes).    

This database contains hauls collated from 1965 to 2019, from fisheries dependent and independent data, from across eastern Atlantic waters and French Mediterranean waters. From this data diadromous fish spatio-temporal data was cleaned and standardised.

This dataset contains bio-optical measurements from BioGeoChemical-Argo (BGC-Argo) profiling floats complemented with ocean-colour satellite matchups of variables related to the detection of coccolithophore blooms dominated by Emiliania huxleyi. BGC-Argo float data cover the global ocean from November 2012 to December 2018 and include measurements of the particulate backscattering coefficient (BBP_float in m-1), the concentration of Chlorophyll-a (CHLA_float in mg m-3), and the particulate beam attenuation coefficient (CP_float in m-1) with data processing and quality control described in the manuscript entitled “Detection of coccolithophore blooms with BioGeoChemical-Argo floats” submitted to Geophysical Research Letters. The data represent near-surface ocean conditions, calculated as the average value in the top 15m of the water column. Daily ocean-colour satellite data were downloaded from the GlobColour project (ftp://ftp.hermes.acri.fr) with a spatial resolution of 4km and matched with every BGC-Argo float observation by using a 5x5 pixel box and a 9-day temporal window. For each float observation, we extracted concurrent satellite data of the concentrations of Particulate Inorganic Carbon (PIC_sat in mmol m-3) and Particulate Organic Carbon (POC_sat in mmol m-3), from which we derived the proportion of PIC_sat to the total particulate carbon concentration (PIC_POC_sat in % and defined as PIC_sat / [PIC_sat+POC_sat]). Coccolithophore bloom periods were identified using annual times series of PIC_sat and PIC_POC_sat at each profile location as described in the submitted manuscript, and the column “inside_coccolithophore_bloom” reports the float observations occurring inside such blooms.

The ICES Working Group on Fisheries Benthic Impact and Trade-offs (WGFBIT) has developed an assessment framework based on the life history trait longevity, to evaluate the benthic impact of fisheries at the regional scale. In order to apply this framework to the Mediterranean sea, several Mediterranean longevity databases were merged together with existing North-East Atlantic ones to develop a common database. Longevity was fuzzy coded into four longevity classes: <1, 1-3, 3-10 and >10 years. Both benthic mega and macrofauna organisms are included in this dataset. Further details about both the purpose and the methodology may be found in ICES (2022) and Cuyvers et al. (2023). The result of the final dataset merging is one dataset containing the fuzzy coded average longevity (and standard deviation) for 2264 taxa and for each, the number of databases used.