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, 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
Constraining Plio‐Pleistocene Shifts in Northwest African Hydroclimate, Ecosystem Distributions, and Marine Productivity: New Paleo‐Records Across the Mid‐Pleistocene Transition
AbstractNorthwest Africa transitioned from a wet/vegetated landscape toward drier/sparser conditions sometime between the late‐Pliocene and the late‐Pleistocene. However, our understanding of the precise timing and nature of this transition is hampered by a paucity of paleo‐records which bridge these two intervals. Here we report new plant‐wax isotope as well as dust and opal flux records from the relatively brief interval ∼1.1–1.0 million years ago (Ma) to evaluate the astronomical timescale controls of Northwest African hydroclimate and vegetation during the Mid‐Pleistocene Transition (MPT) and, in context with published records, the drivers of long‐term climate and ecological trends over the Plio‐Pleistocene. The tempo and amplitude of the Northwest African monsoon rainfall swings closely track low latitude insolation forcings over the last 5 Ma. However, we demonstrate that a pronounced mean state decline in monsoon strength likely occurred following the MPT most likely instigated by increasing Atlantic meridional sea surface temperature gradients or declines in the strength of the meridional overturning circulation. The northward extent of vegetation does not track changes in monsoon strength over the Plio‐Pleistocene and thus may be more strongly influenced by changes in monsoon rainfall extent or ecosystem disturbances. Progressively diminished dust fluxes following a decline in monsoon strength after 1.0 Ma is consistent with reduced production and subsequent depletion of fine‐grained sediments in the Sahara. Synchroneity between dust and opal fluxes across timescales suggests nutrient delivery to the surface ocean via dust plays a key role in marine primary productivity off the coast of Northwest Africa.
(Paleoceanography and Paleoclimatology. vol. 39, n° 2572-4525, 21/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
El Niño-like tropical Pacific ocean cooling pattern during the Last Glacial Maximum
Many state-of-the-art climate models are unable to reproduce the observed 20th century surface warming pattern in the tropical Pacific Ocean, casting doubt on the robustness of future projections. Here, we examine past changes in the tropical Pacific upper ocean spatial pattern using paleoclimate reconstructions from proxies and simulations from a multi-model ensemble. The proxy results demonstrate that during the Last Glacial Maximum, when atmospheric carbon dioxide concentrations were lower than present, temperatures in the western tropical Pacific Ocean decreased more than in the east, leading to an El Niño-like cooling pattern. This result contrasts with the zonally uniform cooling pattern observed in model simulations, highlighting the common issue of models overestimating the sensitivity of eastern tropical Pacific sea surface temperatures to greenhouse forcing. Our proxy results imply that the western Pacific may warm more than the east in response to future climate change, producing a La Niña-like surface warming pattern.
(Communications Earth & Environment. vol. 5, n° 2662-4435, pp. 587, 21/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, MARUM, QMUL, NTU
Caractérisation des réservoirs silicoclastiques du Trias inférieur à la méso-échelle, un aquifère aux enjeux locaux, nationaux et européens
(. vol. 83, pp. 118, 21/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GR, UR, INSU - CNRS, CNRS
L'impact du numérique. Avis CTES sur les actions menées en 2023-2024
Cet avis porte sur l’impact du numérique en lien avec les activités de l’université. Il évalue les actions mises en place par l’université dans le cadre des engagements décrits dans la Feuille de route des transitions environnementales et sociétales de l’université (Feuille de route), notamment l’engagement 15.
(pp. 10 p., 21/06/2026)
BSE, UB, CNRS, INRAE, LOMA, UB, CNRS, ImmunoConcept, UB, INSERM, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Revealing the profound influence of diapause on gene expression: Insights from the annual transcriptome of the copepod Calanus finmarchicus
Abstract Annual rhythms are observed in living organisms with numerous ecological implications. In the zooplanktonic copepod Calanus finmarchicus , such rhythms are crucial regarding its phenology, body lipid accumulation, and global carbon storage. Climate change drives annual biological rhythms out of phase with the prevailing environmental conditions with yet unknown but potentially catastrophic consequences. However, the molecular dynamics underlying phenology are still poorly described. In a rhythmic analysis of C. finmarchicus annual gene expression, results reveal that more than 90% of the transcriptome shows significant annual rhythms, with abrupt and dramatic upheaval between the active and diapause life cycle states. This work explores the implication of the circadian clock in the annual timing, which may control epigenetic mechanisms to profoundly modulate gene expression in response to calendar time. Results also suggest an increased light sensitivity during diapause that would ensure the photoperiodic entrainment of the endogenous annual clock.
(Molecular Ecology. vol. 33, n° 0962-1083, 21/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, SAMS, MIAT INRAE, INRAE, JMU, AWI, HIFMB, OFFIS
Influence de la morphologie dunaire sur les flux éoliens et le transport sédimentaire : Exemple sur la côte Aquitaine
L'évolution des dunes côtières est d'une importance stratégique vis-à-vis du risque de submersion dans un contexte d'érosion de nombreux littoraux sableux. Leur dynamique est contrôlée par les interactions complexes entre les facteurs biotiques et abiotiques, notamment le vent incident, la morphologie de la dune et la densité de végétation. La littérature décrit les caractéristiques du vent lors du franchissement d'un système plagedune ainsi que du transport sédimentaire associé pour de nombreux environnements. Toutefois, il n'est pas documenté à ce jour, comment deux systèmes à la morphologie contrastée répondent à une même tempête. Dans ce cadre, une campagne de terrain de 3 jours a été réalisée sur deux sites voisins de la côte Aquitaine (La Teste-de-Buch (S1) et Biscarrosse (S2)) en simultanée. Ils présentent des morphologies contrastées avec une dune fixée par la végétation au front dunaire abrupte (36°) en S1 et une dune libre, au profil doux (11°) en S2. L'étude repose sur l'acquisition de données de vent à l'aide de 21 anémomètres répartis sur les deux sites d'étude, complétée en plusieurs endroits par l'analyse qualitative de panaches de fumigènes capturés par vidéo. Enfin, des mesures de transport sédimentaire ont également été réalisées en différentes positions sur le long des profils. Les résultats mettent en évidence le rôle de la morphologie sur le comportement du vent lors du franchissement de la dune favorisant en S2 un transport sédimentaire pouvant atteindre 200 kg/m²/h au niveau de la crête. Les sédiments transportés proviennent de la plage et de l'érosion de la face marine de la dune. A contrario, l'impact de la face très abrupte de la dune de S1 sur le vent limite très fortement le transport sédimentaire de la plage vers le haut de la dune. Ainsi, la morphologie de S2 favorise le transfert sédimentaire de la plage vers les terres permettant sur des secteurs en érosion le maintien d'un milieu dunaire dans le temps.
(21/06/2026)
UPVD, CEFREM, UPVD, INSU - CNRS, CNRS, ISMO, CNRS, BRGM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ONF
Inverse Modeling Applications to Coastal Marine Ecosystems
Quantitative estimates of energy or material flows within food webs are increasingly viewed as essential to progress on a number of questions in ecosystem science. Inverse analysis has been used since the 1980s to estimate all flows within plankton food webs originally based on incomplete information. Its application to many aquatic environments, including the coastal zone, has led to a variety of methodological improvements. This chapter explains the methodology of inverse modeling and dynamic modeling that derived from this method and illustrates different application in ecosystems ecology. This approach also provides rigorous statistical comparisons of food web properties across ecosystems using indices from Ecological Network Analysis. Various methodological developments are currently underway and some of them are presented here, with a special focus on the link between static and dynamic modeling.
(pp. 96-121, 21/06/2026)
M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, BOREA, MNHN, IRD, SU, CNRS, UA, BOREA, UNICAEN, NU, MNHN, IRD, SU, CNRS, UA, ULaval, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NIOZ, UKZN, UMR MARBEC, IRD, IFREMER, CNRS, UM, IMR, IMR, UiB, UR EABX, INRAE, MIAME, UPPA, INRAE, OFB, Institut Agro
A new species of Malacoceros (Annelida, Polychaeta, Canalipalpata, Spionidae) from urban waters in Gabon
A new species of Malacoceros is described from estuarine equatorial waters in Libreville (Gabon, West Africa). During a recent environmental study aimed to assess the urban impact on an estuarine ecosystem near Libreville, the collection of sediment samples from the area was undertaken. The local invertebrate macrofauna had not been previously well studied, and to document the biodiversity, specimens were examined in more detail. A new species of Malacoceros was discovered, occurring in mangrove areas. The new species is described and illustrated in detail, and information on three molecular markers was retrieved and partially used for species delimitation analysis. The new species resembles Malacoceros indicus (Fauvel 1928) described from India but is easily distinguished by a very conspicuous morphological character, the presence of 7–11 large tubercles along the anterior margin of the prostomium. The presence of such conspicuous tubercles has never been observed before in Malacoceros. Maximum likelihood trees for species of Malacoceros and the close genera of Rhynchospio, for which we have data, are also provided. The suitability of characters used for species delimitation in Malacoceros is discussed.
(African Zoology, n° 1562-7020, pp. 1--16, 21/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR MARBEC, IRD, IFREMER, CNRS, UM