Temperature and hydrological variations during the late-glacial in the Central Mediterranean: Application of the novel ostracod-clumped isotope thermometer
This study shows, for the first time, the absence of a vital effect in the clumped isotope carbonate (Δ47) fossil ostracod signal and confirms the ability of the novel ostracod-Δ47 thermometer to reconstruct past temperatures and hydrological conditions in complex lacustrine systems. Furthermore, the application of Δ47 analyses on the ostracod species Candona angulata and Cyprideis torosa from Lake Trasimeno record (central Italy), which today precipitate their shells during the cold and the warm season respectively provides evidence that by combining biological (i.e., ostracod shell precipitation timing), paleontological (i.e., identification of ostracod species) and geochemical (i.e., Δ47) approaches, the ostracod-Δ47 thermometer accurately reconstructs past seasonality. Despite the absence of a vital effect, not all species can be combined for Δ47 analyses in environments with seasonal temperature variations; only those that precipitate their shells during the same season should be considered. The application of the ostracod-Δ47 thermometer on the Trasimeno lacustrine record gives rise to the first continental warm season paleotemperature reconstruction of the last 43 ky in central Mediterranean area. The combination of Δ47 and oxygen isotope composition (δ18Oost) measured on ostracod shells provides the isotopic composition of the water from which the carbonate precipitated (δ18Ow) and thereby, changes in the evaporation/precipitation balance in this area. Before the Last Glacial Maximum (LGM), equivalent to the Marine Isotopic Stage 3 (MIS3, from 43 to 29ky), warm season temperatures ranged from 15 ± 1.6 °C to 22 ± 2.3 °C, equivalent to 2 to 6 °C colder than today. Hydrological conditions during this period are similar to the present-day ones, characterized by a permanent lake and a high evaporation/precipitation ratio (E/P). The drastic decrease of the warm season temperatures (ranging from 10 ± 2.9 °C to 17 ± 3.1 °C) and of the E/P ratio during LGM and Late-glacial (MIS2, from 29 to 11.6 ky) correspond to the global climate cooling and low summer insolation, suggesting an amplifying role, of the latter, in the effects of the millennial scale climatic variations. At the Pleistocene/Holocene transition, both warm season temperature (25 ± 2 °C) and the E/P ratio increased in conjunction with the summer insolation. During the early Holocene, warm season temperature (23 ± 2 °C) closely resembles present-day values. However, cold season temperature (12 ± 2 °C) is approximately 4 °CC warmer than today. Notably, no hydrological differences are identified between the warm and the cold season underlying a lower seasonality contrast compared to the present, along with enhanced warm season precipitation. The good agreement between the Δ47 temperatures reconstructed for the last 1 ky and the temperatures presently recorded at Lake Trasimeno (8 °C cold and 22 °C for warm season), confirms the accuracy of the analyses and the applicability of the ostracod-Δ47 thermometer to reconstruct seasonal temperature changes.
(Earth and Planetary Science Letters. vol. 625, n° 0012-821X, pp. 118470, 01/01/2024)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Expertise préalable à la création d’un tableau de maladie professionnelle ou à l’élaboration de recommandations aux comités régionaux de reconnaissance des maladies professionnelles - Expertise sur les tableaux de maladies professionnelles existants nécessitant une mise à jour
La commission chargée d'évaluer le coût de la sous-déclaration des accidents du travail et des maladies professionnelles pour la branche maladie instituée par l’article L. 176-2 du code de la Sécurité Sociale (CSS), a régulièrement souligné que la non-reconnaissance de certaines maladies professionnelles pouvait être due notamment « à l’obsolescence de certains tableaux de maladies professionnelles qui n’intègrent pas l’état des connaissances scientifiques et épidémiologiques, et, d’autre part, à la limitation des pathologies qu’ils peuvent prendre en compte pour ce qui est des durées d’exposition et des produits et substances prévus ». Le dernier rapport issu des travaux de la commission sur la sous-déclaration des AT-MP, remis au Parlement en juillet 2021 (Commission sur la sous-déclaration des accidents du travail et des maladies professionnelles 2021), mettait ainsi en avant le caractère inadapté ou incomplet de certains tableaux de maladies professionnelles (TMP), s’agissant notamment de la désignation de la maladie ou des travaux associés. Compte tenu des évolutions des connaissances relatives aux modalités diagnostiques des maladies indiquées dans les TMP mais aussi aux travaux en lien avec ces maladies, la Direction générale du travail, la Direction de la Sécurité sociale et le Secrétariat général du ministère de l’agriculture et de la souveraineté alimentaire ont saisi l’Anses le 16 mars 2023 pour réaliser un travail d’expertise visant à étudier d’une part l’opportunité scientifique et médicale d’actualiser les différents tableaux, et d’autre part de disposer, pour chaque tableau, des raisons justifiant ou non une évolution des conditions d’accès à ces tableaux.
(pp. 113 p., 01/01/2024)
Irset, UA, UR, EHESP, INSERM, Biosit : Biologie - Santé - Innovation Technologique, IRIS, EHESS, INSERM, CNRS, UJML, UMRESTTE UMR_T9405, UCBL, INED, UBO UFR MSS EUMB, UBO EPE, CHRU Brest, CESP, UVSQ, AP-HP, AP-HP, INSERM, UB, EPICENE, BPH, UB, INSERM, NU, IRISSO, PSL, CNRS, INRAE, CONSTANCES, UVSQ, INSERM, UPCité, INSERM, LABERS, UBS, UBO EPE, IBSHS, UBO EPE, AU, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, DER, ANSES, DiSSES, ANSES
Reproduction of Marphysa sanguinea Annelida, Polychaeta (Eunicidae), at Mount Edgecombe, Plymouth, near the type locality in Southwest England
The reproductive cycle of Marphysa sanguinea is described for a population at Mount Edgecombe, Plymouth, near the type location in Southwest England, using a data set obtained previously (October 1999 to September 2000). The species is iteroparous without schizogamy, spawning prior to October 1999 and during a short breeding season in 2000 from end August through September. The sexes are separate with a sex ratio of 1:1. Mature oocytes and spawned eggs are 215 μm in diameter and spermatozoa of the ectaqua sperm type. Mature gametes of both sexes are discharged through paired coelomoducts, and the diploid chromosome number is 28. Proliferation of new coelomic gametes from paired gonads began within a month of spawning and continued for 8–9 months but ovulation was suppressed in June and July. Attempts to undertake fertilisation using spawned oocytes and active spermatozoa were unsuccessful. The size of discharged oocytes suggests a short pelagic larval duration of a few days. This is the first publication about the reproduction of this species, and our results suggest that M. sanguinea is restricted to intertidal areas in SW England, NW France and southern North Sea. The highly synchronised pattern of reproduction observed is not compatible with a quasi-cosmopolitan species range indicating that this species has been mistakenly reported from around the world. Future studies of the genus should combine rigorous taxonomy with observations of reproduction to facilitate comparison among Marphysa spp.
(Journal of the Marine Biological Association of the United Kingdom. vol. 104, n° 0025-3154, pp. e19, 14/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Fish gut and skin microbiota dysbiosis induced by exposure to commercial sunscreen formulations
UV filters (organic or mineral) present in sunscreen products are emerging contaminants of coastal aquatic environments. There is an urgent need to understand marine organisms responses to these compounds. In this study, we investigated the effect of exposure to dilutions of commercial sunscreen formulations on bacterial communities of mullet (Chelon sp.). The gut and skin mucus microbial communities were characterized using a metabarcoding approach targeting the 16S rRNA gene. Our results revealed that mullets had its own bacterial communities that differ from their surrounding habitats and specific to tissue. The dilutions of commercial sunscreens modified the relative abundance of Actinobacteroita, Bacteriodota and Proteobacteria for both gut and skin microbiota. They also allowed to bacteria affiliated to Mycobacterium, Nocardia and Tenacibaculum genera, known to house pathogenic species, to colonize the epithelium which may have implications for fish host health.
(Aquatic Toxicology. vol. 266, n° 0166-445X, pp. 106799, 14/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LIENSs, INSU - CNRS, ULR, CNRS, LEMAR, IRD, IFREMER, UBO EPE, CNRS
Caractérisation de l’hydrodynamisme des plages et des petits fonds du littoral au sud de l’estuaire de la Gironde à partir de mesures in situ
Le littoral Nord-Médoc, situé au sud de l'estuaire de la Gironde, est soumis à des conditions hydrodynamiques complexes, résultant de l'interaction entre des houles énergétiques et des courants tidaux intenses au sein d'un environnement alternant platiers rocheux, bancs de sables et chenaux de marée. La résultante est un gradient hydrodynamique latitudinal influençant fortement l'évolution morphologique de la côte. Une campagne de mesures de deux semaines a été menée en automne 2022 pour caractériser pour le première fois in situ cette dynamique. Les données ont été collectées le long de trois profils cross-shore s'étendant des petits fonds à l'estran. Les résultats issus de courantomètres profileurs (i.e. ADCP, Aquadopp) et de capteurs de pression ont pu montrer la prédominance des courants tidaux sur l'ensemble du site d'étude (i.e. courant longitudinaux), avec une intensification notable du nord vers le sud. Cette tendance se caractérise par une dominance des courants de flot au Nord, tandis que le jusant domine au sud et au centre du domaine d'étude. Les observations sur les vagues et les courants, en plus d'apporter des éléments de compréhension inédits sur les dynamiques hydrosédimentaires, constituent une base de données indispensable à la validation des modèles de circulation et les prévisions d'évolution du trait de côte dans cette région soumise à l'érosion chronique
(pp. 215-223, 14/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, BRGM, LIENSs, INSU - CNRS, ULR, CNRS
Campus bien-être". Avis CTES sur les actions menées en 2023-2024
Les engagements évoqués dans cet avis sont répertoriés dans la Feuille de route des transitions de l’université de Bordeaux (2022), désormais remplacée par un Schéma directeur des transitions environnementales et sociétales (2024). Cet avis porte sur certains aspects de la qualité de vie sur le campus et la promotion d’une politique sociale, et en particulier, l’engagement 19 qui concerne la promotion d’un campus santé.
(pp. 16 p., 14/10/2026)
BSE, UB, CNRS, INRAE, LOMA, UB, CNRS, ImmunoConcept, UB, INSERM, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Biodiversité. Avis CTES sur les actions menées en 2023-2024
Les engagements évoqués dans cet avis sont répertoriés dans la Feuille de route des transitions de l’université de Bordeaux (2022), désormais remplacée par un Schéma directeur des transitions environnementales et sociétales (2024). Cet avis porte sur l’engagement 12 (engagement principal) mais aussi sur les engagements 2, 7, 11 et 19, dans le but d’intégrer la biodiversité et sa préservation dans la gestion de nos campus. L’avis se penche d’abord sur l’engagement 12 (voir encadré), et propose ensuite des recommandations générales autour de 5 axes, et émet ensuite des recommandations spécifiques pour chacun des autres engagements.
(pp. 15 p., 14/10/2026)
BSE, UB, CNRS, INRAE, LOMA, UB, CNRS, ImmunoConcept, UB, INSERM, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Impact of water level management on organic carbon availability and nitrogen transformations in wetland sediments
The impact of water level management via water retention on benthic carbon and nitrogen fluxes was studied in a wetland of the Seine estuary. Carbon and inorganic nitrogen fluxes at the sediment-water interface were determined during periods of intermittent and permanent immersion along a lateral gradient. In addition to fluxes, nitrate reduction rates, quantity and quality of both sedimentary and dissolved organic carbon, and organic matter lability via external enzymatic activities were analyzed. During both periods, the sediments subject to water level management facilitated nitrogen removal, with potential NO3- fluxes averaging -109 ± 31 nmol NO3- cm-2 h-1 under permanent immersion and -34 ± 13 nmol NO3- cm-2 h-1 under intermittent immersion. During permanent immersion, more water retention favors a higher input of dissolved organic matter including fresh and labile compounds, which most likely explained the significantly higher NO3- influxes. Intermittent immersion resulted in a lower quantity of retained dissolved organic matter, which likely explains the low N fluxes. The results of this study indicate the implementation of water retention strategies can markedly enhance NO3- removal by increasing the availability of organic matter. This underscores the importance of considering water-level management of wetlands to sustain the ecological functions of these valuable ecosystems, which are often the first barriers against environmental disturbance.
(Science of the Total Environment. vol. 947, n° 0048-9697, pp. 174643, 14/10/2026)
ECOBIO, UR, INEE-CNRS, CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Environmental controls on the distribution of brGDGTs and brGMGTs across the Seine River basin (NW France): implications for bacterial tetraethers as a proxy for riverine runoff
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial lipids that have been widely used as environmental proxies in continental paleorecords. Another group of related lipids, branched glycerol monoalkyl glycerol tetraethers (brGMGTs), has recently been proposed as a potential paleotemperature proxy. Nevertheless, the sources and environmental dependencies of both brGDGTs and brGMGTs along the river–sea continuum are still poorly understood, complicating their application as paleoenvironmental proxies in some aquatic settings. In this study, the sources of brGDGTs and brGMGTs and the potential factors controlling their distributions are explored across the Seine River basin (NW France), which encompasses the freshwater-to-seawater continuum. BrGDGTs and brGMGTs were analyzed in soils, suspended particulate matter (SPM), and sediments (n=237) collected along the land–sea continuum of the Seine basin. Both types of compounds (i.e., brGDGTs and brGMGTs) are shown to be produced in situ, in freshwater and saltwater, based on their high concentrations and distinct distributions in aquatic settings (SPM and sediments) vs. soils. Redundancy analysis further shows that both salinity and nitrogen dominantly control the brGDGT distributions. Furthermore, the relative abundance of 6-methyl vs. that of 5-methyl brGDGTs (the IR6Me ratio), the total nitrogen (TN), the δ15N, and the chlorophyll a concentration co-vary in a specific geographical zone with low salinity, suggesting that 6-methyl brGDGTs are preferentially produced under low-salinity and high-productivity conditions. In contrast to brGDGTs, the brGMGT distribution appears to be primarily regulated by salinity, with a distinct influence on the individual homologues. Salinity is positively correlated with homologues H1020a and H1020b and negatively correlated with compounds H1020c and H1034b in SPM. This suggests that bacteria living in freshwater preferentially produce compounds H1020c and H1034b, whereas bacteria that primarily grow in saltwater appear to be predominantly responsible for the production of homologues H1020a and H1020b. Based on the abundance ratio of the freshwater-derived compounds (H1020c and H1034b) vs. their saltwater-derived homologues (H1020a and H1020b), a novel proxy, the Riverine IndeX (RIX), is proposed to trace riverine organic matter inputs, with high values (>0.5) indicating a higher riverine contribution. We successfully applied RIX to the Godavari River basin (India) and a paleorecord across the upper Paleocene and lower Eocene from the Arctic Coring Expedition at Lomonosov Ridge, showing its potential applicability to both modern samples and paleorecords.
(Biogeosciences. vol. 21, n° 1726-4170, pp. 2227-2252, 14/10/2026)
METIS, EPHE, PSL, INSU - CNRS, SU, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ECOBIO, UR, INEE-CNRS, CNRS, CNRS, LEFE, INEE-CNRS, CNRS, UT3, Comue de Toulouse, CNRS, Toulouse INP, Comue de Toulouse
A Revised Marine Fossil Record Of The Mediterranean Before And After The Messinian Salinity Crisis
The Messinian salinity crisis and its precursor events have been the greatest environmental perturbation of the Mediterranean Sea to date, offering an opportunity to study the response of marine ecosystems to extreme hydrological change and a large-scale biological invasion. The restriction of the marine connection between the Mediterranean and the Atlantic Ocean resulted in stratification of the water column and high-amplitude variations in seawater temperature and salinity already from the early Messinian. Here, we present a unified and revised marine fossil record of the Mediterranean (https://doi.org/10.5281/zenodo.13358435, Agiadi et al., 2024) that covers the Tortonian stage, the pre-evaporitic Messinian stage, and the Zanclean stage and encompasses 23 032 occurrences of calcareous nannoplankton, dinoflagellates, foraminifera, corals, ostracods, bryozoans, echinoids, mollusks, fishes, and marine mammals. This record adheres to the FAIR principles, is updated in terms of taxonomy, and follows the currently accepted stratigraphic framework. Based on this record, knowledge gaps are identified, which are due to spatiotemporal inconsistencies in sampling effort and the distribution of sedimentary facies, as well as the inherent differences in the preservation potential between the groups. Additionally, sampling bias in old records may have distorted the record in favor of larger, more impressive taxa within groups. This record is now ready to be used to answer both geological and biological questions about the Mediterranean Sea and beyond and is amendable when new fossil data are brought to light.
(Earth System Science Data. vol. 16, n° 1866-3508, pp. 4767-4775, 14/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS