Canyon Heads and River Plumes: How Might They Influence Neritic Planktonic Foraminifera Communities In The SE Bay of Biscay?
The present study discusses the distribution of living planktonic foraminifera (LPF) in a neritic environment from the SE Bay of Biscay. Four sites, located at the head of Capbreton Canyon and near the Adour River mouth, were sampled during four cruises between June 2006 and July 2008. Each site was sampled with a plankton net (>100 μm) to characterize the LPF communities. The four onshore stations are here compared to three offshore stations located along a bathymetric transect on the Plateau des Landes to document the influence of submarine canyon bathymetry and river input on LPF communities. Five major species were observed: Globigerina bulloides, Globigerinella calida-G. bulloides complex, Neogloboquadrina pachyderma dextral, Globorotalia inflata, and Turborotalita quinqueloba. Late spring (mid-June 2006) standing stocks showed a decreasing trend toward the coast, whereas fall (late November 2007) and summer (mid-July 2008) standing stocks showed higher values at the canyon head and onshore stations. High standing stocks dominated by specimens from the G. calida-G. bulloides complex were recovered in late November 2007 at neritic stations and could be related to upwelling and/or strong tidal currents in the submarine Capbreton Canyon. Their distribution and production in the SE Bay of Biscay is affected by the Adour River turbidity discharge and also by mesoscale upwelling events induced around the Capbreton Canyon head.
(Journal of Foraminiferal Research. vol. 42, n° 0096-1191, pp. 257 - 269, 12/04/2026)
BIAF, UA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS
Spatial and long-term changes in the functional and structural phytoplankton communities along the French Atlantic coast
Spatial and interannual variations of phytoplankton diversity were characterized along the French Atlantic Coast in relation to physical factors and large-scale climatic indices using phytoplankton surveys conducted from 1993 to 2010 in four geographical areas. This study relates phytoplankton diversity to oyster recruitment success by comparing a 'specific' versus a 'functional' diversity approach. Functional diversity was represented by functional groups of different phytoplanktonic functional traits (size, shape, toxicity), relevant for oyster feeding during growth, reproduction and larval development. Phytoplankton diversity patterns along the French Atlantic coast corresponded to a geographical distribution mainly driven by a latitudinal gradient and hydrodynamic features as confirmed by the functional characteristics of the indicator species recorded for each geographical area (C-S-R strategies of Reynolds, specific habitat). This geographical typology was less clear for functional diversity. Only few functional groups were explained by physical factors: the non-toxic small and solitary cells were in particular related to temperature, with high densities observed in the southern areas. Even if temporal variation was less important in explaining the phytoplankton diversity patterns, the main drivers explaining the interannual pattern were the large-scale climatic indices, mainly the Atlantic Multidecennal Oscillation. Functional groups were readily explained by climatic indices than species even if the relationships cannot be applied generally because of the non-linearity of the correlations (local and temporal variations). However, the potentially toxic, small and linear phytoplankton were anticorrelated to NAO. The functional approach thus brings constructive elements concerning the relationships between the prey assemblage of oysters and their physical drivers. Redundancy and co-inertia analyses appeared as complementary analyses in investigating phytoplankton pattern of variation, being particularly useful in analyzing geographical and temporal diversity fluctuation, respectively. © 2012.
(Estuarine, Coastal and Shelf Science. vol. 108, n° 0272-7714, pp. 37--51, 12/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IFREMER, LIENSs, INSU - CNRS, ULR, CNRS, DYNECO, IFREMER, BOREA, UNICAEN, NU, MNHN, IRD, SU, CNRS, UA, CNRS, UNICAEN, NU, NU
Événements extrêmes (submersion estuarienne et crue) dans le Médoc viticole : Quels changements environnementaux pour la qualité géochimique des eaux de l’estuaire de la Gironde ?
L’estuaire de la Gironde (sud-ouest de la France) a été marqué au cours de ces dernières décennies par des événements météorologiques majeurs (Tempêtes Martin en 1999, Xynthia en 2010), responsables d’importantes inondations (submersions estuariennes et crues). Dans un contexte de changements globaux (augmentation du niveau de la mer, urbanisation croissante, …), des incertitudes persistent quant à la fréquence de ces événements. A ces incertitudes s’ajoute une méconnaissance des impacts géochimiques sur la qualité des sols et des eaux de l’estuaire, consécutifs à la remise en eau temporaire des terrains riverains principalement viticoles, pouvant être fortement contaminés en certains métaux. A partir d’une base de données existantes sur les catastrophes naturelles (GASPAR) et d’une base météorologique, nous avons identifié les communes les plus sinistrées du Médoc sur lesquelles nous avons collecté des sols qui ont subi des tests de lixiviation en laboratoire. Pour cela, les sols ont été mis au contact avec de l’eau douce ou estuarienne afin d’identifier les processus de relargages ou piégeages en métaux et simuler, ainsi, l’impact des inondations. Les paramètres des tests de lixiviation ont été déterminés à partir de la détermination des caractéristiques des événements (type, durée, saison). Cette étude s’inscrit dans un programme de recherche pluridisciplinaire Adapt’eau (ANR CEP&S 2011), qui vise à étudier les impacts des changements globaux et à expérimenter des options d’adaptation sur l’environnement fluvio-estuarien Garonne-Gironde, notamment la dépoldérisation. Dans cette perspective, notre recherche apporte des éléments d’éclairage sur l’impact de la remise en eaux des terres viticoles sur la Garonne-Gironde.
(pp. 17, 12/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR ADBX, IRSTEA
Responses and structural recovery of periphytic diatom communities after short-term disturbance in some rivers (Hanoi, Vietnam)
Field transfer experiments of periphytic diatom assemblages developed on artificial substrates were set up to assess the responses of those communities to environmental disturbances. The glass slides were positioned for colonization at the relatively unpolluted site (Red, in the Red River) and at the heavily polluted site (TL, in the To Lich River) in the beginning of the experiment. After a period of 2 weeks, the colonized glass slides were concomitantly transferred from the unpolluted Red site to the heavily polluted TL site and to the moderate polluted site (NT 2, in the Nhue River) and, conversely, from the TL site to the Red site, and then to the NT 2 site. The responses and the adapting capacity of periphytic diatom communities to environmental changes were assessed through the cell density, diversity index, species richness, taxonomic composition, and diatom indices after 2 and 4 weeks of transfer periods. For all transfers except for the transfer from the Red to the TL site in which the growth inhibition of diatom cells was found, the diatom density significantly increased until the end of the experiment. Thus, the diatom communities have expressed their pollution tolerance or sensitivities by changing their composition to adapt themselves to environmental changes. Characteristic species of the Red site (Gyrosigma scalproides, Navicula recens) were replaced by Nitzschia palea, Nitzschia umbonata, Aulacoseira granulate typical species of the NT 2 site, in the biofilm transferred from the Red site to the NT 2 site. The relative abundances of typical diatom species of the Red site proliferated in the biofilm transferred from the TL site to the Red site. The replacement of periphytic diatom communities appeared after the transfer from the second week at the different sites. The slow shift of the species towards the typical species at the TL site could result from the organized structure of diatoms within biofilm before the transfer from the Red site to the TL site. The shifts in values of the Index of Specific Polluosensitivity and Diatom Assemblage Index to organic pollution throughout the experiment indicated the clear sensitivity of these indices to water quality changes.
(Journal of Applied Phycology. vol. 24, n° 0921-8971, pp. 1053-1065, 12/04/2026)
IRSTEA, UR REBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IRSTEA
L'hydrodynamique du lagon sud-ouest
La circulation des eaux dans le lagon sud-ouest Nouvelle-Calédonie est due à trois agents principaux : la marée, le vent local et le déferlement la houle par-dessus le récif-barrière.
(pp. p. 41-44., 12/04/2026)
UAM, ECOLA, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
7000 years of paleostorm activity in the NW Mediterranean Sea in response to Holocene climate events
A high-resolution record of paleostorm events along the French Mediterranean coast over the past 7000 years was established from a lagoonal sediment core in the Gulf of Lions. Integrating grain size, faunal analysis, clay mineralogy and geochemistry data with a chronology derived from radiocarbon dating, we recorded seven periods of increased storm activity at 6300-6100, 5650-5400, 4400-4050, 3650-3200, 2800-2600, 1950-1400 and 400-50 cal yr BP (in the Little Ice Age). In contrast, our results show that the Medieval Climate Anomaly (1150-650 cal yr BP) was characterised by low storm activity.;The evidence for high storm activity in the NW Mediterranean Sea is in agreement with the changes in coastal hydrodynamics observed over the Eastern North Atlantic and seems to correspond to Holocene cooling-in the North Atlantic. Periods of low SSTs there may have led to a stronger meridional temperature gradient and a southward migration of the westerlies. We hypothesise that the increase in storm activity during Holocene cold events over the North Atlantic and Mediterranean regions was probably due to an increase in the thermal gradient that led to an enhanced lower tropospheric baroclinicity over a large Central Atlantic-European domain. (C) 2011 University of Washington. Published by Elsevier Inc. All rights reserved.
(Quaternary Research. vol. 77, n° 0033-5894, pp. 1-11, 12/04/2026)
UAG, INSU - CNRS, UM, CNRS, EDYTEM, USMB [Université de Savoie] [Université de Chambéry], CNRS, Fédération OSUG, Géosciences Montpellier, UAG, INSU - CNRS, UM, CNRS, IDES, UP11, INSU - CNRS, CNRS, UAG, INSU - CNRS, UM, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, GEOTRAC, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, GLACCIOS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA
Effects of copper and cadmium spiked-sediments on embryonic development of Japanese medaka (Oryzias latipes)
Because of their high capacity to accumulate contaminants such as persistent organic pollutants and heavy metals, aquatic sediments are considered as a long-term source of contamination for aquatic organisms. In compliance with the increasing interest both for sediment quality evaluation and the use of fish early life stage (ELS) toxicity assays, we proposed an embryo-larval test to evaluate embryotoxicity and genotoxicity of sediment-bound contaminants. Pre-blastula stage medaka (Oryzias latipes) embryos were exposed by static sediment contact to two model heavy metals (cadmium and copper) at environmental concentrations during the whole 10-day embryonic development. Lethal and sub-lethal effects were recorded in both embryos and larvae for 20 days post fertilisation (dpf) using several global toxicity and phenotypic endpoints. The comet assay was also performed on medaka prolarvae to evaluate genotoxic effects of the tested chemicals. Environmental concentrations of cadmium (Cd) and copper (Cu) did not affect embryo and larval survival. However, both heavy metals significantly induced morphological abnormalities, particularly spinal and cardiovascular deformities. Cd but not Cu induced tachycardia. Both heavy metals induced a significant increase in DNA damage at all tested concentrations. Resulting LOEC values for Cd and Cu corresponded to 1.9 and 8.5 μg/g d.w. sediment, respectively. Although metal bioavailability is probably lower for naturally contaminated sediments, the relatively low toxicity thresholds for both Cd and Cu raise the question of possible risk for fish embryos developing in direct contact to sediments. This study demonstrates the applicability, sensitivity and relevance of the Japanese medaka embryo-larval assay (MELA) to evaluate sediment hazardous potency at environmental concentrations of heavy metals.
(Ecotoxicology and Environmental Safety. vol. 79, n° 0147-6513, pp. 272-282, 12/04/2026)
SEBIO, INERIS, URCA, ULH, NU, URCA, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Embryotoxic and genotoxic effects of heavy metals and pesticides on early life stages of Pacific oyster (Crassostrea gigas)
This study evaluated embryotoxicity and genotoxicity of two dissolved metals copper and cadmium (Cu and Cd) and two pesticides (metolachlor and irgarol) occurring in Arcachon Bay (SW France) in Pacific oyster (Crassostrea gigas) larvae and investigated the relationship between those two endpoints. Embryotoxicity was measured by calculating the percentage of abnormal D-shaped larvae and genotoxicity was evaluated with DNA strand breaks using the comet assay. After 24 h exposure, significant increases of the percentage of abnormal D-larvae and the DNA strand breaks were observed from 0.1µg/L for Cu, 10 µg/L for Cd and 0.01 µg/L for both irgarol and metolachlor in comparison with the controls. A strong positive relationship between embryotoxicity and genotoxicity was recorded for Cu, Cd and metolachlor. The current study suggests that copper, irgarol and metolachlor can induce larval abnormalities and DNA damage in a population of exposed oysters at environmentally relevant concentrations.
(Marine Pollution Bulletin. vol. 64, n° 0025-326X, pp. 2663-2670, 12/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR MALY, IRSTEA
Evaluation of the efficiency of wastewater advanced treatments and sludge treatments through chemical analysis of 168 selected compounds and non-target analysis
The general objective of the ECHIBIOTEB research program (“Innovating tools for sampling, chemical and biological analyses for the diagnosis of wastewater advanced tertiary treatments and sludge treatments”, 2011-2014, financed by the French National Research Agency, coordinated by Irstea) is to use innovative and complementary tools to characterize the efficiency of water advanced treatments and sludge treatments in wastewater treatment plant. To achieve this goal, various strategies were combined: chemical analysis of a large panel of selected priority and emerging contaminants, non-target chemical analysis, in vitro and in vivo biological analysis and innovating sampling tools such as integrative samplers (e.g. POCIS (Polar Organic Chemical Integrative Sampler) and SPMD (Semi-Permeable Membrane Device)). Our presentation will focus on results on the chemical analyses of selected molecules and non-target analysis. Until today, 11 sampling campaigns, 8 for water and 3 for sludge, have been conducted. Among the potential treatments used for advanced (or tertiary) water treatments, ozone (O3), Granular Activated Carbon (GAC), O3 + GAC, ozone peroxide (H2O2) and UV/H2O2 were studied in full scale or large scale pilot design, located on the outlet of secondary biological treatments. For sludge treatments, solar dryer, compost and reed-bed filter were tested. A total of 138 contaminants belonging to pharmaceuticals, oestrogenic hormones, alkylphenols (AkP), Endocrine Disruptor Compounds (EDC), Polycyclic Aromatic Hydrocarbons (PAH) and pesticides were measured in the dissolved phase of water samples; and 113 contaminants, belonging to pharmaceuticals, oestrogenic hormones, AkP, EDC, organochlorine pesticides, PAH, PCB (PolyChloroBiphenyl) and PBDE (PolyBrominated DiphenylEthers) were measured in sludge samples. After extraction by adapted methods such as Liquid-Liquid Extraction, Solid Phase Extraction or Solid Phase MicroExtraction for waters, and Accelerated Solvent Extraction or microwave extraction for sludge, molecules were analysed by gas (GC) or liquid phase chromatography coupled with single or tandem mass spectrometry. Non-target analysis were realised with two-dimensional GC coupled to Time Of Flight mass spectrometer. For most of the compounds, targeted analysis showed a significant reduction in contaminant concentration in the dissolved phase of water after all tested treatments. Indeed, pharmaceuticals and AkP were efficiently eliminated with concentrations in effluents respectively about 100 and 10 times lower than in influents. In contrast, aminomethylphosphonic acid (AMPA) and glyphosate were not eliminated at all from secondary wastewaters. Many of the selected compounds are refractory to conventional secondary treatments; nonetheless, we demonstrated that they can be efficiently removed thanks to selected advanced tertiary treatments. In the presentation, we will discuss which treatment seems to be the most efficient to eliminate the selected compounds. Depending on the process and the contaminant class, concentrations in raw and treated sludge varied widely. Non-target analyses of 3 different sludge samples allowed to obtain a list of 190 molecules of interest, among which some nitrogen heterocyclic compounds as potential emerging contaminants. Further investigations are needed, especially combining chemical with biological analysis, to determine which compounds among these 190 would be the most relevant to be considered in environmental studies.
(pp. 19, 12/04/2026)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Mercury concentrations in sediments of the Suquia River Basin, Cordoba, Argentina.
(12/04/2026)
Bordeaux INP, UBM, SPE, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS