Early back-calculated size-at-age of Atlantic yellow eels sampled along ecological gradients in the Gironde and St. Lawrence hydrographical systems
An international sampling program investigating the causes of the decline of American eels (Anguilla rostrata) and European eels (Anguilla anguilla) in the St. Lawrence (Canada) and Gironde (France) rivers systems provided the opportunity to compare early growth of eels of each species among habitats using back-calculated size
(Canadian Journal of Fisheries and Aquatic Sciences. vol. 75, n° 0706-652X, pp. 1270-1279, 20/10/2026)
INRS, DFO-MPO, UR EABX, IRSTEA, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Multi-decadal to centennial hydro-climate variability and linkage to solar forcing in the Western Mediterranean during the last 1000 years
Here we present a new composite record from two well-dated speleothem records from two caves in Northern Morocco. The high-resolution record covers the last millennium allowing to detect multi-decadal to centennial periodicities. Over the industrial period, δ18O values of our speleothems are shown to be dominated by the main mode of decadal variability in the North Atlantic region: the North Atlantic Oscillation (NAO). Statistical analyses confirm the previously reported multi-decadal variability related to the influence of the Atlantic Multidecadal Oscillation (AMO) in the region. High power and persistent centennial-scale periodicities, similar to the Vries-Suess 200-year solar cycle, are observed as well. Indeed, comparison between solar activity reconstructions and our record confirms the in-phase relationship on centennial time-scales. Low δ18O values, and hence negative phases of NAO that bring precipitation towards the Western Mediterranean, are observed during well-known solar minima periods. The results are consistent with previous models which describe low irradiance as a trigger for southward shifts of precipitation-bearing westerlies during winter.
(Scientific Reports. vol. 8, pp. 17446, 20/10/2026)
Xjtu, MPIC, USP, LOCEAN-VALCO, LOCEAN, MNHN, IRD, INSU - CNRS, SU, CNRS, IPSL (FR_636), ENS-PSL, UVSQ, CEA, INSU - CNRS, X, CNES, SU, CNRS, UPCité, JGU, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMN, UMN
Influence of recent climatic events on the surface water storage of the Tonle Sap Lake
Lakes and reservoirs have been identified as sentinels of climate change. Tonle Sap is the largest lake in both the Mekong Basin and Southeast Asia and because of the importance of its ecosystem, it is has been described as the “heart of the lower Mekong”. Its seasonal cycle depends on the annual flood pulse governed by the flow of the Mekong River. This study provides an impact analysis of recent climatic events from El Niño 1997/1998 to El Niño 2015/2016 on surface storage variations in the Tonle Sap watershed determined by combining remotely sensed observations, multispectral images and radar altimetry from 1993 to 2017. The Lake's surface water volume variations are highly correlated with rainy season rainfall in the whole Mekong River Basin (R = 0.84) at interannual time-scale. Extreme droughts and floods can be observed when precipitation deficit and excess is recorded in both the Tonle Sap watershed and the Mekong River Basin during moderate to very strong El Niño/La Niña events (R = −0.70) enhanced by the Pacific Decadal Oscillation (R = −0.68). Indian and Western North Pacific Monsoons were identified as having almost equal influence. Below normal vegetation activity was observed during the first semester of 2016 due to the extreme drought in 2015.
(Science of the Total Environment. vol. 636, n° 0048-9697, pp. 1520-1533, 20/10/2026)
GET, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CESBIO, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, INRAE, LOG, INSU - CNRS, ULCO, CNRS, IRD [Ile-de-France], LMTG, UT3, Comue de Toulouse, CNRS
Distribution and (palaeo)ecological affinities of the mainSpiniferitestaxa in the mid-high latitudes of the Northern Hemisphere
In marine sediments of late Cenozoic age, Spiniferites is a very common genus of dinoflagellate cysts (dinocysts). Despite some taxonomical ambiguities due to large range of morphological variations within given species and convergent morphologies between different species, the establishment of an operational taxonomy permitted to develop a standardized modern database of dinocysts for the mid-high latitudes of the Northern Hemisphere. In the database that includes 1490 surface sediment samples, Spiniferites mirabilis-hyperacanthus, Spiniferites ramosus and Spiniferites elongatus were counted in addition to Spiniferites belerius, Spiniferites bentorii, Spiniferites bulloideus, Spiniferites delicatus, Spiniferites lazus and Spiniferites membranaceus. Among these taxa, Spiniferites mirabilis-hyperacanthus, Spiniferites ramosus, and Spiniferites elongatus are easy to identify and are particularly common. Spiniferites bentorii and Spiniferites delicatus also are morphologically distinct and occur in relatively high percentages in many samples. Spiniferites lazus and Spiniferites membranaceus also bear distinctive features, but occur only in a few samples. The identification of other taxa (Spiniferites belerius, Spiniferites bulloideus, notably) may be equivocal and their reported distribution has to be used with caution. The spatial distribution of Spiniferites species, with emphasis on the five most common taxa, is documented here with reference to hydrography (salinity and temperature in winter and summer, sea ice cover), primary productivity and geographical setting (bathymetry, distance to the coastline). The results demonstrate distinct ecological affinities for Spiniferites elongatus, which has an Arctic-subarctic distribution and appears abundant in low productivity environments characterized by winter sea ice and large temperature contrast between winter and summer. Spiniferites mirabilis-hyperacanthus, which occurs in warm temperate water sites, is more abundant in high salinity environments. It shares its environmental domain with Spiniferites bentorii, which appears to have a narrower distribution towards the warm and high salinity end of the Spiniferites mirabilis-hyperacanthus distribution. In contrast, Spiniferites delicatus, which occurs in warm-temperate to tropical environments, shows preference for relatively low salinity and low seasonal contrasts of temperature. Spiniferites ramosus exhibits a particularly wide distribution that overlaps both cold and warm Spiniferites taxa. Its cosmopolitan occurrence and its long-ranging biostratigraphical distribution suggest a high plasticity of the species and/or co-occurrence of several cryptic species. Hence, whereas Spiniferites elongatus and Spiniferites mirabilis-hyperacanthus are useful palaeoecological indicators despite their large morphological variability, Spiniferites ramosus is a taxon with an unconstrained ecological significance.
(Palynology. vol. 42, n° 0191-6122, pp. 182-202, 20/10/2026)
UQAM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GEUS, AWI, UVIC, ISMER, UQAR
The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments: a summary of round table discussions
We present a summary of two round-table discussions held during two subsequent workshops in Montreal (Canada) on 16 April 2014 and Ostend (Belgium) on 8 July 2015. Five species of the genus Achomosphaera Evitt 1963 and 33 of the genus Spiniferites Mantell 1850 emend. Sarjeant 1970 occuring in Pliocene to modern sediments are listed and briefly described along with remarks made by workshop participants. In addition, several holotypes and topotypes are reillustrated. Three species previously assigned to Spiniferites are here considered/accepted as belonging to other genera: Impagidinium inaequalis (Wall and Dale in Wall et al. 1973) Londeix et al. 2009, Spiniferites? rubinus (Rossignol 1962 ex Rossignol 1964) Sarjeant 1970, and Thalassiphora balcanica Balteş 1971. This summary forms the basis for a set of papers that follows, where points raised during the workshops are explored in greater detail.
(Palynology. vol. 42, n° 0191-6122, pp. 10-44, 20/10/2026)
DGD.REVE, MNHN, GEOTOP, EPM, UdeM, UQAT, UQAR, UQAM, UCPH, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CR2P, MNHN, SU, CNRS, LGO, UBS, IFREMER, UBO EPE, CNRS, ISMER, UQAR, LSU
Migrations néandertaliennes et variations climatiques pendant le Saalien supérieur. Apport des modélisations analogiques en enceintes thermo-regulées
(pp. 23-24, 20/10/2026)
CReAAH, UM, UR, UR2, CNRS, UFR HHAA, UN, MC, NSU, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Deglacial to postglacial history of Nares Strait, Northwest Greenland: a marine perspective from Kane Basin
A radiocarbon-dated marine sediment core retrieved in Kane Basin, central Nares Strait, was analysed to constrain the timing of the postglacial opening of this Arctic gateway and its Holocene evolution. This study is based on a set of sedimentological and geochemical proxies of changing sedimentary processes and sources that provide new insight into the evolution of ice sheet configuration in Nares Strait. Proglacial marine sedimentation at the core site initiated ca. 9.0 cal ka BP following the retreat of grounded ice. Varying contributions of sand and clasts suggest unstable sea ice conditions and glacial activity, which subsisted until ca. 7.5 cal ka BP under the combined influence of warm atmospheric temperatures and proglacial cooling induced by the nearby Innuitian (IIS) and Greenland (GIS) ice sheets. An interval rich in ice-rafted debris (IRD) is interpreted as the collapse of the ice saddle in Kennedy Channel ca. 8.3 cal ka BP that marks the complete opening of Nares Strait and the initial connection between the Lincoln Sea and northernmost Baffin Bay. Delivery of sediment by icebergs was strengthened between ca. 8.3 and ca. 7.5 cal ka BP following the collapse of the buttress of glacial ice in Kennedy Channel that triggered the acceleration of GIS and IIS fluxes toward Nares Strait. The destabilisation in glacial ice eventually led to the rapid retreat of the GIS in eastern Kane Basin at about 8.1 cal ka BP as evidenced by a noticeable change in sediment geochemistry in our core. The gradual decrease in carbonate inputs to Kane Basin between ∼ 8.1 and ∼ 4.1 cal ka BP reflects the late deglaciation of Wash-ington Land. The shoaling of Kane Basin can be observed in our record by the increased winnowing of lighter particles as the glacio-isostatic rebound brought the seabed closer to subsurface currents. Reduced iceberg delivery from 7.5 to 1.9 cal ka BP inferred by our dataset may be linked to the retreat of the bordering ice sheets on land that decreased their number of marine termini.
(Climate of the Past. vol. 14, n° 1814-9324, pp. 1991-2010, 20/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ULaval, INSU - CNRS, CNRS, CEN, ULaval, ISMER, UQAR
Relative Contribution of Wave Setup to the Storm Surge: Observations and Modeling Based Analysis in Open and Protected Environments (Truc Vert beach and Tubuai island)
(20/10/2026)
BRGM, IFREMER, DYNECO, IFREMER, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Manganese incorporation in living (stained) benthic foraminiferal shells: a bathymetric and in-sediment study in the Gulf of Lions (NW Mediterranean)
Manganese geochemistry in deep-sea sediments is known to vary greatly over the first few centimeters, which overlaps the in-sediment depth habitats of several benthic foraminiferal species. Here we investigated manganese incorporation in benthic foraminiferal shell carbonate across a six-station depth transect in the Gulf of Lions, NW Mediterranean, to unravel the impacts of foraminiferal ecology and Mn pore water geochemistry. Over this transect water depth increases from 350 to 1987m, while temperature ( ∼ 13°C) and salinity ( ∼ 38.5) remained relatively constant. Manganese concentrations in the tests of living (rose bengal stained) benthic foraminiferal specimens of Hoeglundina elegans, Melonis barleeanus, Uvigerina mediterranea, and Uvigerina peregrina were measured using laser ablation inductively coupled mass spectrometry (laser ablation ICP-MS). Pore water manganese concentrations show a decrease from shallow to deeper waters, which corresponds to a generally decreasing organic-matter flux with water depth. Differences in organic-matter loading at the sediment–water interface affects oxygen penetration depth into the sediment and hence Mn pore water profiles. Mn∕Ca values for the investigated foraminiferal species reflect pore water geochemistry and species-specific microhabitat in the sediment. The observed degree of variability within a single species is in line with known ranges in depth habitat and gradients in redox conditions. Both the Mn∕Ca ratio and interspecific variability hence reflect past Mn cycling and related early diagenetic processes within the sediment, making this a potential tool for bottom-water oxygenation and organic-matter fluxes. Dynamics of both in-sediment foraminiferal depth habitats and Mn cycling, however, limit the application of such a proxy to settings with relatively stable environmental conditions.
(Biogeosciences. vol. 15, n° 1726-4170, pp. 6315-6328, 20/10/2026)
LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Zones Humides : des écosystèmes riches mais menacés
Les zones humides de la Nouvelle-Aquitaine constituent des écosystèmes très variés du point de vue morphologique et écologique. Cette richesse s'exprime également à travers la fourniture de nombreux services au territoire. Cependant, les dynamiques fonctionnelles des zones humides sont peu à peu menacées par le changement climatique, ce qui implique de reconsidérer à l'avenir leur rôle dans le développement du territoire. À l'aide d'une typologie exprimée en termes d'état et de pressions, les zones humides de Nouvelle-Aquitaine sont analysées pour rendre compte des principaux facteurs susceptibles d'impacter leur profil et leur évolution à long terme au niveau des fonctions et des services associés. Étant donnée la diversité des zones humides présentes dans la région, un exercice de prospective n'a pas pu être mené dans le détail pour tous les types de zones humides. La prospective la plus aboutie, développée ici concerne les marais rétro-littoraux et les lagunes/estuaires, afin de mesurer l'influence des impacts du changement climatique. Finalement, la dynamique de ces écosystèmes est à la fois déterminée par des facteurs naturels (changement dans les communautés planctoniques, submersion marine...) et par des facteurs socio-économiques (rôle des zones humides dans les services écosystémiques, aménagement, gestion intégrée des ressources en eau...). Dans ce contexte, il apparaît essentiel d'approfondir nos connaissances fondamentales, de disposer d'outils/indicateurs pour identifier les transformations des zones humides et de leurs usages, et d'entreprendre l'évaluation de ces socioécosystèmes particuliers à la fois en termes de patrimoine biologique et de services délivrés à la société.
(pp. 331-361, 20/10/2026)
UR EABX, IRSTEA, LIENSs, INSU - CNRS, ULR, CNRS, GREThA, UB, CNRS, GEOLAB, UBP, IR SHS UNILIM, UNILIM, UCA [2017-2020], CNRS, UCA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS