From fixed to transgressive dunes, the conditions and timing of the transition along the Aquitaine coast, France
Today most of the coastal dunes in temperate latitudes, especially in the northern hemisphere, are relatively stable. However, over the last decade, the Gironde coast, southwest France, has experienced substantial natural dune remobilization following a major marine erosion event. Annual, large-scale and highresolution, airborne LiDAR data and Satellite imagery (Sentinel-2) are combined to address the coastal dune morphological changes and establish relations with forcing and controlling factors (vegetation cover, geomorphological descriptors). Between 2014 and 2023, about 10 out of 85 km of the Gironde dunes have switched from fixed to transgressive state. The analysis showed that in the vast majority of the cases the dominant process involved was dune front cannibalism. However, there is considerable spatial and temporal variability along the coast, depending on the vegetation cover evolution, the amount of sediment remobilized and the morphological characteristics of the dunes (steepness of the front slope, width).
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Valve behavior of the European flat oyster Ostrea edulis and underwater temperature, recorded during a 18-month in situ experiment in Helgoland, Germany
This dataset shows the hourly valve behavioral data of the 16 oysters Ostrea edulis throughout the 18 months of the experiment (11th of May 2023 - 31st of August 2024) in Helgoland (Margate) as well as the temperature recorded by the HFNI valvometer. The oyster valve behavior is characterized by 3 parameters: the Valve Opening Amplitude (VOA, the percentage of the valve opening relative to maximum opening), the Valve Opening Duration (VOD, the percentage of time that an oyster spends with its valves open), and the VOA/VOD. The data are presented for each oyster and as a group average. Missing data corresponds to the death of the oyster number 7 or to the stop of recording due to electrical failure on the oyster's valvometer electrodes.
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, AWI, AWI
Valve behavior of the European flat oyster Ostrea edulis and associated underwater sound and temperature data, recorded during a 18-month in situ experiment in Helgoland, Germany
Once widespread across European coasts, the native flat oyster Ostrea edulis has now disappeared from most of its historical range and is officially recognized as threatened. As a key ecological engineer, this species supports biodiversity by filtering water, stabilizing sediments, and providing complex reef habitats. Understanding and evaluating its behavior and biological rhythms in a natural environment before reintroduction, and how it responds to natural geophysical cycles, is essential to support effective restoration strategies. However, current knowledge on O. edulis remains limited, with most studies focusing primarily on reproduction under aquaculture or laboratory conditions. To help fill this gap, we conducted a 18-month in situ study to assess the valve behavior of Ostrea edulis in the field. The experiment took place at the Margate site (54.19°, 7.88°) near the island of Helgoland (Germany) from the 11th of March 2023 to the 31st of August 2024. The experimental setup consisted of 16 oysters disposed on individual cages in a customized oyster basket placed on a lander, a metallic structure immersed at 10m depth. Their valve behavior was continuously measured during 18 months using a High-Frequency Non-Invasive (HFNI) valvometer biosensor (Tran et al. 2023; Le Moal et al. 2023 for further details). Briefly, a pair of lightweight electrodes (<100 mg) was glued on each half-shell of each oyster and was linked to the HFNI valvometer by a flexible wire, allowing undisturbed oyster valve movement. An electromagnetic field was generated between the electrodes, allowing the measurement of the distance between each oyster's valve in continuous mode. In addition to the oyster behavior, environmental parameters were continuously measured underwater by the HFNI valvometer biosensor during the experiment, such as temperature and sound pressure magnitude. This compilation of datasets gives an overview of environmental parameters and behavioral data collected during this experiment.
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, AWI, AWI
Hourly physicochemical parameters measured underwater on oyster tables during a one-year semi-controlled experiment
This dataset shows the hourly physicochemical parameters measured underwater throughout the year of the experiment. The temperature and water depth were measured on each oyster table (control and ALAN conditions, at the oyster's level), while the turbidity was measured only on the ALAN table, and conductivity and salinity were measured only on the control table.
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Hourly irradiance data measured underwater on oyster tables during a one-year semi-controlled experiment
This dataset shows the hourly irradiance data measured underwater on each oyster table (control and ALAN conditions, at the oysters' level) throughout the year of the experiment as well as the temperature recorded by each irradiance sensor.
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Hourly sound pressure magnitude data measured underwater on oyster tables during a one-year semi-controlled experiment
This dataset shows the hourly sound pressure magnitude data measured underwater on each oyster table (control and ALAN conditions, at the oyster's level) throughout the year of experiment for different frequencies (10 Hz, 20 Hz, 30 Hz, 40 Hz, 50 Hz, 60 Hz, 70 Hz, 80 Hz, 90 Hz, 100 Hz, 200 Hz, 300Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz). The mean sound pressure magnitude is also presented for each condition. In the ALAN condition, data are missing from August 13, 2024, until the end of the experiment due to the failure of the hydrophone used.
(24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Les spéléothèmes enregistreurs des environnements passés et marqueurs de l’histoire des grottes
Les spéléothèmes, dépôts carbonatés des grottes, constituent des archives reconnues des variations climatiques. Grâce à la possibilité de les dater par radiochronologie, ils fournissent de précieux jalons chronologiques sur l’histoire géomorphologique des grottes, des occupations humaines passées et permettent d'évaluer les changements environnementaux avec une grande précision sur des centaines de milliers d’années. Leur étude est une science en pleine évolution, très prometteuse en termes de quantification des paramètres climatiques. Les spéléothèmes sont cependant issus d’un milieu fragile, qui doit être géré avec précaution afin de protéger ces témoins uniques du passé.
(Dynamiques Environnementales - Journal international des géosciences et de l’environnement. vol. 54-55, n° 1968-469X, pp. 1-53, 24/05/2026)
CEREGE, IRD, AMU, CdF (institution), INSU - CNRS, CNRS, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
The influence of large-scale climate patterns on sediment loss from agricultural land—exploration using an instrumented field and catchment scale platform
Accelerated soil erosion and sediment delivery are threats to water quality. In Western Europe, weather patterns are strongly influenced by large scale climate systems such as the North Atlantic Oscillation (NAOi). Recently, however, a new climate index has been developed, called the West Europe Pressure Anomaly (WEPAi), which may be more relevant for weather in North Western Europe. Recent attempts have tried to link variability in weather patterns as described by hydro-climatic indices and amplifications in the degradation of water quality. However, to our knowledge, no previous work has been undertaken on investigating their effects on suspended sediment concentrations (SSCs). A study was conducted in southwest England using long-term meteorological, monthly NAOi and WEPAi, and 15 min discharge and turbidity datasets collected from an instrumented field and catchment scale monitoring platform. Monthly winter precipitation totals, and air temperature were both found to be significantly positively related to NAOi, but not in the summer. Both variables were significant and more strongly related with the WEPAi for both seasons. Flow weighted mean SSCs calculated for both seasons over a 4 year period were compared to monthly NAOi and WEPAi. In winter months, no significant relationships were found at any scale for NAOi. However, significant positive relationships with the WEPAi were present regardless of catchment size. In the summer months there were no significant relationships with either climate indices. Large-scale climate drivers are important in the sediment responses of agricultural landscapes. An ability to forecast monthly climate scale drivers could enable farmers to better plan for those periods when hydro-sedimentological responses are likely to be elevated. More work is needed across a range of landscape typologies to confirm that the relationships observed hold true more widely.
(Environmental Research Letters. vol. 20, n° 1748-9326, pp. 044023, 24/05/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Assessing the invasion risk of the cnidaria Blackfordia virginica Mayer, 1910: a threat to the Baltic Sea ecosystem?
The ecological role, bloom extent and long-term dynamics of jellyfishes are mostly overlooked due to sampling limitations, leading to the lack of continuous long-term datasets. A rise in frequency and magnitude of jellyfish invasion around the world is shedding new light on these organisms. In this study, we estimate the current and future distribution of the introduced jellyfish Blackfordia virginica in the Baltic Sea. We determine the combination of favorable levels of temperature and salinity for this species by analyzing presence/absence data from areas outside the Baltic Sea and project the distribution of suitable habitat in the Baltic Sea across different scenarios with variable climate forcing and eutrophication levels. Our results show that suitability increases with rising temperature and optimal salinity range from 13 to 20 for this species. In addition, a relatively large area of the Baltic Sea represents favorable abiotic conditions for B. virginica , enhancing the concerns on its potential range expansion. Spatial analysis illustrates that the coastal areas of the southern Baltic Sea are particularly at risk for the invasion of the species. The observation of the projection of habitat suitability across time highlights that future Baltic Sea environmental conditions increase suitability levels for B. virginica and suggest a potential expansion of its distribution in the future.
(Biological Invasions. vol. 27, n° 1387-3547, pp. 106, 24/05/2026)
BOREA, MNHN, IRD, SU, CNRS, UA, GEOMAR, CCMAR, UAlg, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Altitudinal evolution of vegetation on the Vercors Massif since the Late Glacial Period: new pollen data from Combe‑Chevalière (Chichilianne, Isère, 1,650 m)
The Combe Chevalière provided an interesting sequence for reconstructing the subalpine vegetation over the last 18,000 years. This sequence, derived from a wetland area and documented in parallel with a sedimentological study, is subject to periods of low water input that lead to the drying of the area and, consequently, low or no sedimentation, as well as poorer preservation of pollen assemblages compared to other sediment types. The studied sequence is therefore incomplete, and despite a sedimentary hiatus at the Preboreal level, it still provides insight into the vegetation dynamics near the study area, at the subalpine level, as well as at the upper limit of the montane zone. Since Combe Chevalière is bordered by areas of Mesolithic occupations, this study provides an environmental context for these sites. The palynological analysis of Combe Chevalière follows numerous other studies conducted at different vegetation levels, thus contributing to a broader analysis of vegetation evolution within the Vercors Massif. The vegetation evolution is consistent with the various vegetation zones. Late-glacial climatic variations are characterized by oscillations of Pinus, Betula, and Juniperus in the hill and montane zones, while the more rigorous climate of the subalpine zone is dominated by herbaceous plants. Pinus and deciduous trees were present in the sub-alpine zone since 9,000 years ago (cal. BP), and were replaced by herbaceous and Picea during the Subboreal. Competition with Abies, recorded since 7,800 cal. BP, seems to be the cause of the decrease in this taxon from the Subatlantic period onwards. Human impact also varies with altitude. In the hill zone, Juglans, Castanea, and Populus were cultivated during the Subatlantic period, while at the same time, in the montane zone, human activity is reflected in the forest exploitation of Abies.
(Quaternaire. vol. Vol.36/1, n° 1142-2904, pp. 1 - 19, 24/05/2026)
EPHE, PSL, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS