Study of benthic foraminiferal faunas along the French Mediterranean coasts: a new biotic index in the EU Water Framework Directive
(25/10/2026)
LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Conditions for tidal bore formation in convergent alluvial estuaries
(Estuarine, Coastal and Shelf Science. vol. 172, n° 0272-7714, pp. 121 - 127, 25/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CARDAMOM, IMB, UB, Bordeaux INP, CNRS, Inria
Ideas and perspectives: Southwestern tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica
Recent Southern Hemisphere (SH) atmospheric circulation, predominantly driven by stratospheric ozone depletion over Antarctica, has caused changes in climate across the extratropics. Here, we present evidence that the Brazilian coast (southwestern Atlantic) may have been impacted from both wind and sea-surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air–sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.
(Biogeosciences. vol. 13, n° 1726-4170, pp. 2379-2386, 25/10/2026)
LARAMG, UERJ, USP, BTP, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NTU
Spatial distribution of living (Rose Bengal stained) benthic foraminifera in the Loire estuary (western France)
Ninety-seven surface sediment samples were collected in September 2012 from intertidal and subtidal areas along the Loire estuary (western France). The main objective of this work is to study the spatial distributional patterns of living benthic foraminifera and their link to the environmental parameters (distance to sea, elevation, grain size, total organic carbon, trace metals, sedimentary carbonates, and polycyclic aromatic hydrocarbons) in the Loire estuary. Foraminiferal analysis was also extended to the dead assemblages in thirty-three surface samples from the lower inner estuary. The highest absolute densities of living benthic foraminifera are found in the lower inner estuary within the polyhaline domain. This is attributed to the presence of mudflats with abundant food source, i.e. microphytobenthos. The low densities found in the outer estuary (euhaline domain) are attributed partly to the sandy nature of the sediments and the food source inhabiting this substrate. The near absence of foraminifera in the inner estuary (mesohaline and polyhaline domains) is inferred to the physical disturbance resulting from the regular dredging of the navigation channel. The living assemblages are dominated by three typical estuarine species: Ammonia tepida and Haynesina germanica in the intertidal mudflats of the lower inner estuary and Cribroelphidium excavatum in the sandy subtidal sediments of the lower inner and outer estuary. In the Loire estuary, H. germanica has an unusual intermediate geographical distribution along the estuary between A. tepida and C. excavatum while in most temperate estuaries this species is present upstream in the mesohaline domain. This is most likely the result of the regular dredging of the navigation channel damaging its natural habitat. This might be also the explanation for the total absence of agglutinated species usually dominating the oligohaline domain. The canonical correspondence analysis shows that elevation (and its link to time of emersion), distance to sea (and its correspondence with salinity), and organic carbon content appear to be the primary drivers of foraminiferal distribution. The present study provides for the first time ecological and distribution patterns of living benthic foraminiferal communities in the Loire estuary. This baseline knowledge is necessary for the future studies focusing on the use of benthic foraminifera as bio-indicators in the Loire estuary and in transitional environments in general.
(Journal of Sea Research (JSR). vol. 118, n° 1385-1101, pp. 1-16, 25/10/2026)
BIAF, UA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LETG-Angers, LETG, UNICAEN, NU, UA, EPHE, PSL, UBO EPE, UR2, CNRS, IGARUN, UN
Integration of contamination peaks with variable intensity and duration by the Polar Organic Chemical Integrative Sampler
Nowadays, pesticides, considering their efficiency on animal and plant parasites, represent considerable progress in food resources management and public health improvement. However, due to intensive use, the three environment compartments (water, air, soil) are contaminated with worrying consequences for human being and ecosystem. In order to conserve and restore the condition of aquatic environments, the European Water Framework Directive (WFD) was adopted in 2000 by the European Union. Indeed, monitoring networks - such as Water Agencies - proceed to regular monitoring, performing spot water sampling up to 12 times a year. But, there are still questions about the spatial and temporal representativeness of this type of sampling. Actually, contamination level in rivers can vary abruptly, depending on season and hydrology at the sampling moment. Thus, contamination peaks could be undetected by monitoring networks, generating a partial snapshot and then estimation of water quality. Passive sampling techniques are proposed and developed to obtain better representativeness of the contamination level, providing average concentration over time with integration of peculiar events like contamination peaks. In this study, the Polar Organic Chemical Integrative Sampler (POCIS) with different king of membranes was considered. This tool, widely used for polar pesticides sampling (0 < log Kow < 4) (Alvarez et al. 2004), allows pre-concentration in situ of analytes and presents an integrative capacity over several week. Its scope and its technical limitations are actually well documented (Lissalde et al. 2011). Furthermore, it was proved that this device may integrate contamination peaks relatively prolonged (about 3 days) for moderately polar compounds (log Kow = 2-3) (Mazzella et al. 2008). Concerning shorter contamination peaks (few hours-few days) generated by punctual pollutions, interrogations about its reactivity (e.g. lag time) is still remaining. This study aimed to show the POCIS reactivity for three different contamination peak patterns, with variable intensity and duration, over a total exposure period of 14 days. For this experimentation under laboratory controlled conditions, fifteen pesticides covering different polarities (log Kow=0-5) and groups (herbicides, fungicides, insecticides) were selected. The data showed different accumulation kinetic profiles, depending on physico-chemical characteristics of the substances and the exposition duration. Some compounds presented a lag effect, or on the contrary a burst effect. For seven compounds, POCIS sampled correctly contamination peaks, which show the ability of this device to sample fleeting events.
(pp. 39, 25/10/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Un projet intégratif en vue de protéger la qualité des eaux face aux usages de pesticides dans le vignoble Bordelais
Présentation du projet intégratif "PhytoCOTE" du LabEx COTE de l'Université de Bordeaux (coordination générale : Francis Macary) à la délégation mexicaine de scientifiques spécialisés sur la question de la protection de l'eau dans la zone métropolitaine de Léon.
(pp. 20, 25/10/2026)
UR ETBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Modelling the alongshore variability of optimum rip current escape strategies on a multiple rip-channelled beach
Rip currents are a leading cause of drowning on beaches worldwide. How bathers caught in a rip current should attempt to escape has been a subject of recent debate. A numerical model of human bathers escaping from a rip current flow field is applied to a 2-km long section of the open beach of Biscarrosse, SW France. The study area comprises 4 rip channels that visually appear similar from the beach, but exhibit different morphologies. Simulations are run for 2 representative hazardous summer wave conditions. Results show that small changes in the bar/rip morphology have a large impact on the rip flow field, and in turn on the alongshore variability of the optimal rip current escape strategy. The overall flow regime (dominant surf-zone exits versus dominant recirculation), which is found to be influenced by the alongshore dimensions of the sand bars adjacent to the rip channel, is more important to rip current escape strategy than rip velocity. Flow regime was found to dictate the success of the stay afloat strategy, with greater success for recirculating flow. By comparison, the dominant longshore feeder current and rip-neck orientation determined the best direction to swim parallel toward. For obliquely incident waves, swim parallel downdrift then swim onshore with breaking waves was highly successful and can become a simple safety message for beach safety practitioners to communicate to the general public. However, in SW France where rip spacing is large (∼400 m), surf-zone eddies have large spatial scales of the order of 100+ m, requiring a large distance (100+ m) to swim to reach safety, therefore requiring good swimming ability. This also shows that in addition to rip current intensity, rip flow regime and the depth of adjacent sand bars, rip spacing is important for defining rip current hazard and the best safety message. Our results also indicate that for normal to near-normal wave incidence, rip current hazard and best rip current escape strategy are highly variable alongshore due to subtle differences in bar/rip morphology from one rip system to another. These findings challenge the objective of developing a universal rip current escape strategy message on open rip-channelled beaches exposed to normal to near-normal wave incidence, even for seemingly similar rip channels.
(Natural Hazards. vol. 81, n° 0921-030X, pp. 663-686, 25/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UNSW
Spatio-temporal dynamics of per and polyfluoroalkyl substances (PFASs) and transfer to periphytic biofilm in an urban river: case-study on the River Seine
Abstract This study addresses the spatio-temporal dynamics of per and polyfluoroalkyl substances (PFASs) in a highly urbanized freshwater hydrosystem, the Seine River (NW France). The distribution of PFASs between water, sediment, and periphytic biofilm was investigated at three sampling sites along a longitudinal gradient upstream and downstream from the Paris urban area. Seasonal variability was assessed through four sampling campaigns performed under contrasting hydrological conditions. In the dissolved phase, ∑PFASs fluctuated between 2 and 9 ng L−1 upstream and 6–105 ng L−1 downstream from Paris. Negative correlations between dissolved PFAS levels and river flow rate were generally observed, corroborating the predominance of point-source PFAS inputs at these sites. 18/19 target PFASs were detected, with a predominance of PFHxS and PFOS (20% of ∑PFASs each), except for the farthest downstream site where 6:2 FTSA was prevalent (35 ± 8% of ∑PFASs), likely reflecting industrial and urban inputs. In biofilms, ∑PFASs fell in the 4–32 ng g−1 dw range, and substantial bioconcentration factors (BCFs) were reported for PFNA, PFDA, and PFOS (log BCF 2.1–4.3), higher than those of PFHxS or PFOA. BCFs varied inversely with dissolved PFAS levels, potentially pointing to concentration-dependent bioaccumulation. Biofilm community characteristics (C/N ratio) may also be an influential determinant of PFAS bioaccumulation.
(Environmental Science and Pollution Research. vol. 25, n° 0944-1344, pp. 1-9, 25/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR HBAN, IRSTEA
Ideas and perspectives : Southwestern tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica
Recent Southern Hemisphere (SH) atmospheric circulation, predominantly driven by stratospheric ozone depletion over Antarctica, has caused changes in climate across the extratropics. Here, we present evidence that the Brazilian coast (southwestern Atlantic) may have been impacted from both wind and sea-surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air–sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.
(Biogeosciences Discussions. vol. 12, n° 1810-6277, pp. 13193-13213, 25/10/2026)
LARAMG, UERJ, USP, BTP, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, Departamento de Geoquímica, UFF, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NTU, IRD [Ile-de-France]
Proyecto General de Investigación 2012-2017 El Conjunto Monumental de Baelo Claudia, evolución y transformaciones de un espacio público. Análisis diacrónico y multiescalar del sector sureste Fase V. Intervención arqueológica del 13 de abril al 6 de Mayo 2016
(pp. 260, 25/10/2026)
LIENSs, INSU - CNRS, ULR, CNRS, HALMA, CNRS, MC, HeRMA [Poitiers], UP, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS