Remobilisation des radionucléides sous forme d’aérosols primaires et secondaires par vent faible à partir de couverts naturels (projet REMORA) : une nouvelle voie de transfert vers l’atmosphère
(26/04/2026)
IRSN, UMR ISPA, INRA, Bordeaux Sciences Agro, IRCELYON, UCBL, INC-CNRS, CNRS, BFP, INRA, UB, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
RAD sequencing reveals within-generation polygenic selection in response to anthropogenic organic and metal contamination in North Atlantic Eels
(Molecular Ecology. vol. 25, n° 0962-1083, pp. 219--237, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, INRS, IBIS, ULaval
Spatial distribution and toxic potency of trace metals in surface sediments of the Seine estuary (France)
Due to very high anthropogenic pressures and urban waste discharge, the Seine estuary is still among the world's most polluted estuaries. The purpose of this work is to investigate the distribution of trace metals in surface sediments in order to assess to the contamination level, metal bioavailability, and ecotoxicological status. Five sites covering the salinity gradient of the estuary were chosen to evaluate the distribution and contamination level of trace metals in surface sediments. The results showed that trace metal concentration varied seasonally and spatially. Subsequently to assess the actual environmental toxicity of sediments, the Microtox® Bioassay using Vibrio fischeri was applied on aqueous extract of sediment. Calculated enrichment factors revealed that these sediments were highly polluted by mercury, cadmium, zinc, and lead. Most of pollution sources are localized upstream especially in Poses and Oissel, and the contamination levels decreased from Poses to north mudflat site. Positive values of toxicity index were detected in the upstream sediments indicating potential bioavailability of trace metals in the sediments. Sediment toxicity measured with the Microtox® test was positively correlated with toxicity index demonstrating the usefulness of the toxicity index for sediment quality assessment and possible implication of metals in sediment toxicity.
(CLEAN - Soil, Air, Water. vol. 43, n° 1863-0650, pp. 1 -9, 26/04/2026)
FSP III, LU / ULB, LASIRE, INC-CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
The Ponto-Caspian basin as a final trap for southeastern Scandinavian Ice-Sheet meltwater
This paper provides new data on the evolution of the Caspian Sea and Black Sea from the Last Glacial Maximum until ca. 12 cal kyr BP. We present new analyses (clay mineralogy, grain-size, Nd isotopes and pollen) applied to sediments from the river terraces in the lower Volga, from the middle Caspian Sea and from the western part of the Black Sea. The results show that during the last deglaciation, the Ponto-Caspian basin collected meltwater and fine-grained sediment from the southern margin of the Scandinavian Ice Sheet (SIS) via the Dniepr and Volga Rivers. It induced the deposition of characteristic red-brownish/chocolate-coloured illite-rich sediments (Red Layers in the Black Sea and Chocolate Clays in the Caspian Sea) that originated from the Baltic Shield area according to Nd data. This general evolution, common to both seas was nevertheless differentiated over time due to the specificities of their catchment areas and due to the movement of the southern margin of the SIS. Our results indicate that in the eastern part of the East European Plain, the meltwater from the SIS margin supplied the Caspian Sea during the deglaciation until ∼13.8 cal kyr BP, and possibly from the LGM. That led to the Early Khvalynian transgressive stage(s) and Chocolate Clays deposition in the now-emerged northern flat part of the Caspian Sea (river terraces in the modern lower Volga) and in its middle basin. In the western part of the East European Plain, our results confirm the release of meltwater from the SIS margin into the Black Sea that occurred between 17.2 and 15.7 cal kyr BP, as previously proposed. Indeed, recent findings concerning the evolution of the southern margin of the SIS and the Black Sea, show that during the last deglaciation, occurred a westward release of meltwater into the North Atlantic (between ca. 20 and 16.7 cal kyr BP), and a southward one into the Black Sea (between 17.2 and 15.7 cal kyr BP). After the Red Layers/Chocolate Clays deposition in both seas and until 12 cal kyr BP, smectite became the dominant clay mineral. The East European Plain is clearly identified as the source for smectite in the Caspian Sea sediments. In the Black Sea, smectite originated either from the East European Plain or from the Danube River catchment. Previous studies consider smectite as being only of Anatolian origin. However, our results highlight both, the European source for smectite and the impact of this source on the depositional environment of the Black Sea during considered period.
(Quaternary Science Reviews. vol. 148, n° 0277-3791, pp. 29-43 (IF 4,521), 26/04/2026)
GEOPS, UP11, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GM, IFREMER, RMCA
Impact of organic matter source and quality on living benthic foraminiferal distribution on a river-dominated continental margin: A study of the Portuguese margin
Living (rose Bengal stained) benthic foraminifera were investigated on surface sediments from 23 stations from the river-dominated northwestern Portuguese margin. Samples were collected in March 2011, following the period of the maximum rainfall over the Iberian Peninsula, between 20 and 2000 m water depth along five cross-margin transects. Four of them are located off the Douro, Mondego, Tagus, and Sado Rivers and one off the Estremadura coast. The major objectives of this study are (1) to assess the impact of organic matter of various origin and quality on the benthic foraminifera and (2) to investigate the spatial differences of faunal distribution from coastal waters to the deep sea under river influences. To do this, sedimentological and biogeochemical characteristics of the sediments were identified by measuring grain size, oxygen penetration depth, total organic carbon (TOC) content, stable carbon isotopic composition of TOC (δ13CTOC) and concentration of pigments and amino acids. Based on the principal component and cluster analyses of the environmental data, three major geographical groups are identified: (1) deep stations, (2) coastal and middle slope stations, and (3) shelf stations under river influence. At the deepest stations, species are associated with high organic matter (OM) quantity but low OM quality, where Uvigerina mediterranea, Hoeglundina elegans, and agglutinated species such as Reophax scorpiurus or Bigenerina nodosaria are dominant. All stations off the Sado River, which is the most affected area by the anthropogenic influence, are also characterized by high quantity but low quality of OM with the minimum faunal density and diversity within the study area. Middle slope stations are associated with low OM content and coarse sediments (Q50) with the predominance of N. scaphum. Shallow shelf stations close to the Douro and Tagus River mouths show a dominance of taxa (e.g., Ammonia beccarii, Bulimina aculeata, Eggerelloides scaber, Nonion scaphum, Cancris auriculus, and Quinqueloculina seminula) adapted to environments characterized by high OM quality (high fresh chlorophyll (Chl a/Phaeo)) and available amino acids (enzymatically hydrolyzable amino acid (EHAA)/total enzymatically hydrolyzable amino acid (THAA)). The Biotic and Environmental linking analysis suggests that the benthic foraminiferal distribution is mostly controlled by three environmental parameters, i.e., TOC (quantity), EHAA/THAA (quality), and δ13CTOC (source). Hence, this study clearly highlights that the quantitative and qualitative inputs of OM and its source are the most important factors controlling the living benthic foraminiferal distribution with clear influences between the different rivers. This study also suggests a good tolerance of several species for river discharges where the OM quality is high.
(Journal of Geophysical Research: Biogeosciences. vol. 121, n° 2169-8953, pp. 1689-1714, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Stable isotope ratios in bentho-demersal biota along a depth gradient in the Bay of Biscay: A multitrophic study
Although stable isotope ratios are increasingly used to investigate the trophic ecology of marine organisms, their spatial variations are still poorly understood in the coastal environment. In this study, we measured the stable isotope composition (delta C-13, delta N-15) of suspended particulate organic matter (SPOM) (primary producer), a suspension feeder, the great scallop Pecten maximus (primary consumer), megabenthic decapods and benthic fishes (secondary consumers) along a depth gradient (from 5 m to 155 m depth) across the continental shelf of the Bay of Biscay. Although the three trophic levels exhibited similar delta C-13 patterns along the gradient, the delta N-15 patterns varied between SPOM, scallops and carnivores. The delta N-15 difference between SPOM and scallops decreased with increasing depth, suggesting that non trophic factors may affect the stable isotope composition of scallops at deepest sampling stations. An opposed trend was found between scallops and carnivores, suggesting that the trophic level of these carnivores increased at higher depth, possibly as an adaptation to lower prey abundances. Although our results suggest that primary consumers are suitable to establish isotopic baselines in coastal environments, we stress the need for further studies aiming at characterizing the variability of stable isotopes in coastal biota, and the respective effects of baseline, trophic and metabolic factors in their isotopic composition.
(Estuarine, Coastal and Shelf Science. vol. 179, n° 0272-7714, pp. 201-206, 26/04/2026)
LEMAR, IRD, IFREMER, UBO EPE, CNRS, IRD, UBO EPE, CNRS, LIENSs, INSU - CNRS, ULR, CNRS, EMH, IFREMER, IUEM, IRD, INSU - CNRS, UBO EPE, CNRS, ESE, INRA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Heteromysis (Heteromysis) microps (Crustacea, Mysidae), a commensal species for Upogebia pusilla (Crustacea, Upogebiidae) in Arcachon Bay (NE Atlantic Ocean)
Background: The mysid Heteromysis (Heteromysis) microps is reported for the first time in the Bay of Biscay. During surveys carried out between March and September 2015 in Arcachon Bay, mysid specimens were fortuitously collected from Upogebia pusilla burrows. Results: Details on morphology, colour pattern and behaviour of H. microps are provided. Conclusions: Commensalism was frequently mentioned for Heteromysis species but never reported for H. microps. In this study, commensalism seems to be proved between the mysid and its host U. pusilla.
(Marine Biodiversity Records. vol. 9, n° 1755-2672, pp. 14, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Evolution of an exploited resource (Manila clam in the Arcachon Bay) in response to natural and anthropogenic sources of change.
(26/04/2026)
LERAR, COAST, IFREMER, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LMAP, UPPA, CNRS
Shoreline-Sandbar Dynamics at a High-Energy Embayed and Structurally-Engineered Sandy Beach: Anglet, SW France
Anglet beach, Basque Coast (SW France), is a 4-km long embayment bounded by a prominent headland in the South and by the southern Adour River training wall in the North. The beach is structurally-engineered with, within the embayment, 6 groins and 3 distinct sectors where the beach is backed by a seawall. The beach is high-energy intermediate, mostly double-barred, composed of medium to coarse sand with a steep beach face (∼1/10). In January 2013, a video system was installed at the Southern end of Anglet beach at about 70 m above mean sea level to monitor about 2 km of the southern beach of Anglet that includes 4 groins extending about 100 m seaward and a 1- km seawall backing the beach. The study period includes the winter 2013/2014 that was outstanding in terms of the available energy arriving at the coast with a 2-month-averaged significant wave height peaking at 3.6 m. Despite the extreme storm wave conditions during the winter 2013/2014, the outer bar crescentic patterns maintained and even further developed. The beach eroded by O(10 m) and, surprisingly and in contrast with the nearby northern open beaches, they recovered to their pre-winter 2013/2014 state within only a few months. Overall, Anglet beach appears to respond predominantly at individual storm frequency rather than at seasonal timescales, with the groins and headland acting as major controlling boundaries influencing beach state and dictating rip channel locations. \textcopyright Coastal Education and Research Foundation, Inc. 2016.
(Journal of Coastal Research. vol. 1, n° 0749-0208, pp. 393-397, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, SIAME, UPPA
Three non-indigenous species of Aoroides (Crustacea: Amphipoda: Aoridae) from the French Atlantic coast
The amphipod genusAoroidesis reported for the first time in European marine waters. Specimens ofAoroides semicurvatusandAoroides curvipeswere collected in oyster reefs in Arcachon Bay between 2009 and 2014 and in Hossegor Lake in 2014 (SW France). Specimens ofAoroides longimeruswere collected in 2013 and 2014 in subtidal slipper limpet beds andZostera marinameadows in Arcachon Bay and in 2014 on floating pontoons in the Bay of Brest (W France). These species, native to Asia, may have been accidentally introduced in Arcachon Bay and Hossegor Lake with oyster transfers and in the Bay of Brest through both oyster transfers and shipping.
(Journal of the Marine Biological Association of the United Kingdom, n° 0025-3154, pp. 1-9, 21/12/2015)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS