Selective pressure of fishways upon morphological and muscle enzymatic traits of migrating glass eels
Fishways are built on obstacles to restore the connectivity between aquatic habitats. Our study investigated how species-specific fishways interact with interindividual trait differences among fish. We compared several groups of glass eels (Anguilla anguilla) climbing two types of fishways with those remaining below the water impoundments. We analyzed relative body condition factor, body length, mass, and in vitro activities and gene transcription levels of several enzymes involved in the energy metabolism (LDH, CS, CCO, PK). Differences among groups indicated that glass eel fish ladders can be size-specific, according to the type of substrate covering the surface of apparatus. Moreover, we found that climbing specific glass eel ladders can require higher endurance-related metabolic traits, triggering increased aerobic capacities. Increased aerobic efforts together with potential size selectivity of fishways should be taken into account when designing such devices and choosing appropriate location on eel migratory pathways.
(Canadian Journal of Fisheries and Aquatic Sciences. vol. 74, n° 0706-652X, pp. 445-451, 22/10/2026)
UR EABX, IRSTEA, EDF [E.D.F.], EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Impact of explosive volcanic eruptions on the main climate variability modes
(Global and Planetary Change. vol. 150, n° 0921-8181, pp. 24 - 45, 22/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CEP, UNIBE, OCCR, UNIBE, PARVATI, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, UOR, BSC-CNS, CERFACS
The climate of the Common Era off the Iberian Peninsula
The Mediterranean region is a climate hot spot, sensitive not only to global warming but also to water availability. In this work we document major temperature and precipitation changes in the Iberian Peninsula and margin during the last 2000 years and propose an interplay of the North Atlantic internal variability with the three atmospheric circulation modes (ACMs), (North Atlantic Oscillation (NAO), east atlantic (EA) and Scandinavia (SCAND)) to explain the detected climate variability. We present reconstructions of sea surface temperature (SST derived from alkenones) and on-land precipitation (estimated from higher plant n-alkanes and pollen data) in sedimentary sequences recovered along the Iberian Margin between the south of Portugal (Algarve) and the northwest of Spain (Galiza) (36 to 42° N). A clear long-term cooling trend, from 0 CE to the beginning of the 20th century, emerges in all SST records and is considered to be a reflection of the decrease in the Northern Hemisphere summer insolation that began after the Holocene optimum. Multi-decadal/centennial SST variability follows other records from Spain, Europe and the Northern Hemisphere. Warm SSTs throughout the first 1300 years encompass the Roman period (RP), the Dark Ages (DA) and the Medieval Climate Anomaly (MCA). A cooling initiated at 1300 CE leads to 4 centuries of colder SSTs contemporary with the Little Ice Age (LIA), while a climate warming at 1800 CE marks the beginning of the modern/Industrial Era. Novel results include two distinct phases in the MCA: an early period (900-1100 years) characterized by intense precipitation/flooding and warm winters but a cooler spring-fall season attributed to the interplay of internal oceanic variability with a positive phase in the three modes of atmospheric circulation (NAO, EA and SCAND). The late MCA is marked by cooler and relatively drier winters and a warmer spring-fall season consistent with a shift to a negative mode of the SCAND. The Industrial Era reveals a clear difference between the NW Iberia and the Algarve records. While off NW Iberia variability is low, the Algarve shows large-amplitude decadal variability with an inverse relationship between SST and river input. Such conditions suggest a shift in the EA mode, from negative between 1900 and 1970 CE to positive after 1970, while NAO and SCAND remain in a positive phase. The particularly noticeable rise in SST at the Algarve site by the mid-20th century (±1970), provides evidence for a regional response to the ongoing climate warming. The reported findings have implications for decadal-scale predictions of future climate change in the Iberian Peninsula.
(Climate of the Past. vol. 13, n° 1814-9324, pp. 1901-1918, 22/10/2026)
IFREMER, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Origin and distribution of the organic matter in the distal lobe of the Congo deep-sea fan – A Rock-Eval survey
The Congo River, the second largest river in the world, is a major source of organic matter for the deep Atlantic Ocean because of the connection of its estuary to the deep offshore area by a submarine canyon which feeds a vast deep-sea fan. The lobe zone of this deep-sea fan is the final receptacle of the sedimentary inputs presently channelled by the canyon and covers an area of ~2500 km². The quantity and the source of organic matter preserved in recent turbiditic sediments from the distal lobe of the Congo deep-sea fan were assessed using Rock-Eval pyrolysis analyses. Six sites, located at approximately 5000 m water-depth, were investigated. The mud-rich sediments of the distal lobe contain high amounts of organic matter (~3.5 to 4% Corg), the origin of which is a mixture of terrestrial higher-plant debris, soil organic matter and deeply oxidized phytoplanktonic material. Although the respective contribution of terrestrial and marine sources of organic matter cannot be precisely quantified using Rock-Eval analyses, the terrestrial fraction is dominant according to similar hydrogen and oxygen indices of both suspended and bedload sediments from the Congo River and that deposited in the lobe complex. The Rock-Eval signature supports the 70% to 80% of the terrestrial fraction previously estimated using C/N and δ13Corg data. In the background sediment, the organic matter distribution is homogeneous at different scales, from a single turbiditic event to the entire lobe, and changes in accumulation rates only have a limited effect on the quantity and quality of the preserved organic matter. Peculiar areas with chemosynthetic bivalves and/or bacterial mats, explored using ROV Victor 6000, show a Rock-Eval signature more or less similar to background sediment. This high organic carbon content associated to high sedimentation rates (> 2 to 20 mm.yr−1) in the Congo distal lobe complex implies a high burial rate for organic carbon. Consequently, the Congo deep-sea fan represents an enormous sink of terrestrial organic matter when compared to other turbiditic systems over the world.
(Deep Sea Research Part II: Topical Studies in Oceanography. vol. 142, n° 0967-0645, pp. 75-90, 22/10/2026)
EMBS, iSTeP, UPMC, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GM, IFREMER, LDO, INSU - CNRS, UBO EPE, CNRS
First report of the invasive species Branchiomma bairdi McIntosh, 1885(Annelida: Sabellidae) along the Tunisian coast (Mediterranean Sea)
The invasive sabellid polychaete Branchiomma bairdi McIntosh, 1885 was collected in the Boughrara Lagoon (southern Tunisian coast) between 2012 and 2013. This species was originally described from Bermuda and has been widely reported in the Caribbean Sea. It has been considered as non-indigenous species on the Pacific coast of Panama and the California Gulf. Recently, B. bairdi was recorded along the Italian and Turkish coasts, Australia, Canary and Madeira Islands. It was suggested that the commercial shipping is the most likely vector for the introduction of the species to Mediterranean Sea. A description of the species along with a discussion of its systematic position and ecology are provided.
(BioInvasions Records. vol. 6, n° 2242-1300, pp. 139-145, 22/10/2026)
INSTM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LCE, CNRS, UMLP
Recovering water wave elevation from pressure measurements
The reconstruction of water wave elevation from bottom pressure measurements is an important issue for coastal applications, but corresponds to a difficult mathematical problem. In this paper we present the derivation of a method which allows the elevation reconstruction of water waves in intermediate and shallow waters. From comparisons with numerical Euler solutions and wave-tank experiments we show that our nonlinear method provides much better results of the surface elevation reconstruction compared to the linear transfer function approach commonly used in coastal applications. More specifically, our method accurately reproduces the peaked and skewed shape of nonlinear wave fields. Therefore, it is particularly relevant for applications on extreme waves and wave-induced sediment transport.
(Journal of Fluid Mechanics. vol. 833, n° 0022-1120, pp. 399-429, 22/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IMB, UB, Bordeaux INP, CNRS
Organic carbon accumulation in modern sediments of the Angola basin influenced by the Congo deep sea fan
Geochemical data (total organic carbon-TOC content, δ13Corg, C:N, Rock-Eval analyses) were obtained on 150 core tops from the Angola basin, with a special focus on the Congo deep sea fan. Combined with the previously published data, the resulting dataset (322 stations) shows a good spatial and bathymetric representativeness. TOC content and δ13Corg maps of the Angola basin were generated using this enhanced dataset. The main difference in our map with previously published ones is the high terrestrial organic matter content observed downslope along the active turbidite channel of the Congo deep sea fan till the distal lobe complex near 5000 m of water-depth. Interpretation of downslope trends in TOC content and organic matter composition indicates that lateral particle transport by turbidity currents is the primary mechanism controlling supply and burial of organic matter in the bathypelagic depths.
(Deep Sea Research Part II: Topical Studies in Oceanography. vol. 142, n° 0967-0645, pp. 64-74, 22/10/2026)
EMBS, iSTeP, UPMC, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GM, IFREMER, LDO, INSU - CNRS, UBO EPE, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, OCEANIS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA
Calibration of benthic foraminifera elemental ratios from the Northeastern Atlantic
(22/10/2026)
GEOPS, UP11, CNRS, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Role of the Atlantic Multidecadal Variability in modulating the climate response to a Pinatubo-like volcanic eruption
The modulation by the Atlantic multidecadal variability (AMV) of the dynamical climate response to a Pinatubo-like eruption is investigated for the boreal winter season based on a suite of large ensemble experiments using the CNRM-CM5 Coupled Global Circulation Model. The volcanic eruption induces a strong reduction and retraction of the Hadley cell during 2 years following the eruption and independently of the phase of the AMV. The mean extratropical westerly circulation simultaneously weakens throughout the entire atmospheric column, except at polar Northern latitudes where the zonal circulation is slightly strengthened. Yet, there are no significant changes in the modes of variability of the surface atmospheric circulation, such as the North Atlantic Oscillation (NAO), in the first and the second winters after the eruption. Significant modifications over the North Atlantic sector are only found during the third winter. Using clustering techniques, we decompose the atmospheric circulation into weather regimes and provide evidence for inhibition of the occurrence of negative NAO-type circulation in response to volcanic forcing. This forced signal is amplified in cold AMV conditions and is related to sea ice/atmosphere feedbacks in the Arctic and to tropical-extratropical teleconnections. Finally, we demonstrate that large ensembles of simulations are required to make volcanic fingerprints emerge from climate noise at mid-latitudes. Using small size ensemble could easily lead to misleading conclusions especially those related to the extratropical dynamics, and specifically the NAO.
(Climate Dynamics. vol. 51, n° 0930-7575, pp. 1863-1883, 22/10/2026)
BSC-CNS, CECI, CERFACS, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ICREA
Étude de la contamination atmosphérique par les pesticides à l'aide d'échantillonneurs passifs de type PUF (Polyurethane Foam) : application à l'étude de vergers de pommiers
La France, dont plus de la moitié du territoire est dédiée à l'agriculture, se situe au premier rang européen et au cinquième rang mondial des utilisateurs de pesticides agricoles. L'importance de ce secteur et de l'usage de substances chimiques pour accroître la productivité au cours des dernières décennies suscitent des interrogations tant du point de vue environnemental que de celui de la santé publique. Un rapport récent de l'ANSES montre la nécessité de mettre en oeuvre de nouveaux outils et une surveillance nationale des pesticides dans l'air ambiant. En effet, la connaissance des niveaux de contamination en pesticides dans l'atmosphère demeure toujours partielle et hétérogène. De plus, une stratégie spatio-temporelle d'échantillonnage est nécessaire pour l'étude des impacts des pesticides sur l'Environnement et sur la Santé Humaine. Le projet CANEPA (Cancers et Expositions aux pesticides Agricoles ; IdEx U Bordeaux) vise à caractériser la contamination externe des agriculteurs et la contamination environnementale par les pesticides en arboriculture. La technique de l'échantillonnage passif s'est largement développée ces 20 dernières années. Elle permet le suivi de polluants dans l'environnement et peut-être appliquée à l'eau, l'air ou encore le sol. Les échantillonneurs passifs présentent l'avantage d'intégrer la contamination du milieu pendant une période d'exposition donnée et d'abaisser les limites de détection grâce à l'accumulation des substances. Ces outils de surveillance ne nécessitent pas d'énergie et permettent un déploiement spatio-temporel plus pertinent. Au cours de ce projet, un suivi annuel par échantillonnage passif à l'aide de mousses en polyuréthane (PUF) a été mis en place début 2017 au sein d'une exploitation de pommiers pour un suivi des concentrations en pesticides dans l'air intérieur et extérieur afin de mieux comprendre l'exposition des travailleurs agricoles. L'analyse des différents échantillons du projet permettra de déterminer les débits de prélèvements des pesticides détectés dans l'air ambiant. De plus, les basses limites de quantification obtenues au cours des développements analytiques permettent un suivi très large de ces composés.
(pp. 2, 22/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, INSERM U1219 - UB - ISPED, BPH, UB, INSERM, UR ETBX, IRSTEA