Dynamics of low and high density microplastics in the world's largest choked coastal lagoon under contrasting meteoceanographic conditions
The contamination by plastic waste in aquatic environments has become a global issue, scientifically reported since 1970. The size and durability of microplastics (MPs, 1 μm > 5 mm) have made these debris widely distributed in aquatic environments. Despite various ongoing initiatives, there is a need to fill gaps in understanding how MPs are transported from their release sources to their final destinations. Therefore, understanding the distribution and dynamics of MPs in coastal areas, such as lagoons and estuaries, which are considered continental sources of MPs to the oceans, is essential to help fill these gaps and propose alternatives for managing what is the environmental problem of the century. In this context, this study aimed to assess the transport patterns of MPs in Patos Lagoon, the largest choked coastal lagoon in the world, considering contrasting meteoceanographic conditions in the system dynamics, such as wind and discharge. Using the hydrodynamic model TELEMAC-3D and the model for plastics particles TrackMPD, simulations were performed using a type of MP polymer (Polypropylene - PP). The simulations of MP transport considered advection, dispersion and the contribution of biofilm in increasing particle density (representing high-density microplastics). The results indicated a gradient of MPs retention from north to south, with higher concentrations of MPs occurring in the northern part of the system. The central region of the lagoon showed a greater tendency for MP export towards the southern region than retention. Meanwhile, the estuary region of Patos Lagoon exhibited a tendency for export of low-density MPs free of biofilm and retention of higher-density MPs, subject to the action of the Plastisphere. Additionally, based on the results obtained from density occurrence maps, it was possible to suggest potential accumulation areas of MPs throughout the lagoon system, reinforcing that the system can act as a sink in specific regions.
(Continental Shelf Research. vol. 285, n° 0278-4343, pp. 105396, 03/09/2026)
FURG, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Reconstructing the Mid- to Late Holocene human-environments interactions in Cape Corsica (Corsica Island, Western Mediterranean) based on sedimentology, pollen analyses and geochemistry
This paper aims to reconstruct the interactions between human populations and their environment over the last 4500 years in Cape Corsica, a rocky peninsula situated on the northern edge of Corsica Island. During the Iron Age and Roman times, this region in the North Tyrrhenian Sea was at the crossroads of maritime trade routes, and was therefore recognized for its geostrategic position. However, little is known about its exact contribution in terms of natural resources exploitation and land use, nor regarding the general Late Holocene landscape evolution of the area. Three boreholes were drilled in three coastal lagoons situated on the eastern shore of Cape Corsica, at Biguglia, Meria and Macinaggio. To reconstruct the coastal landscape configuration together with vegetation history, land use and mineral extraction, laboratory work comprised granulometry, loss on ignition, pollen identification and elemental geochemistry. The chronostratigraphy is based on nine radiocarbon datings for all cores, and complementary 137Cs and 210Pb measurements were performed on the Meria core for recent chronology. For the northern edge of Cape Corsica, pollen results reveal that the highest human impacts on the vegetation composition were recorded during the Late Neolithic/Early Bronze Age, throughout Roman times, and in the Pisan-Genoese period, respectively. For all these periods, forest and maquis opening was observed to be coeval with cereal cultivation, thus revealing development of agriculture at the northern extremity of Cape Corsica. Conversely, the Middle to Final Bronze Age and pre-Christian era were characterized by a major recovery of the maquis and scarce evidence of land use. At Biguglia lagoon in the southern part of the peninsula, the vegetation composition for the last 1100 years reveals forest opening with moderate development of agriculture and, in the 10th Cent. CE., the connection between San Damiano Island and La Marana coastal barrier. In Cape Corsica, local contamination by mineral extraction (antimony in the form of stibine) is attested in the Meria valley during the known period of exploitation and also prior to this activity, possibly dating from the Genoese or the Corsican independence periods.
(Journal of Archaeological Science: Reports. vol. 62, n° 2352-409X, pp. 104985, 03/09/2026)
CEREGE, IRD, AMU, CdF (institution), INSU - CNRS, CNRS, INRAE, IPHES-CERCA, URV, ULiège, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Record of trace organic contaminants in a river sediment core: A fingerprint of regulatory changes?
This study reconstructs the historical deposition of 76 trace organic contaminants (TrOCs), comprising pharmaceuticals, pesticides, and per-and polyfluoroalkyl substances (PFAS), in a dated sediment core taken from a secondary channel of the Seine River downstream of the Paris conurbation. Sediment chronology, established through $^{210}$Pb and $^{137}$Cs radionuclide depth activities, spans the period from 1943 to 2022, providing a long-term record of anthropogenic influence on fluvial contamination. The vertical profiles of pharmaceutical residues reveal temporal patterns closely aligned with their respective dates of market introduction, followed by increasing concentrations and subsequent declines. Maximum TrOC sedimentary concentrations were observed during the 1980s, coinciding with incomplete wastewater collection coverage. A sharp decrease in concentrations post-2000 reflects significant improvements in wastewater collection and treatment infrastructure. For pesticides, sedimentary trends also correlate with usage history and regulatory actions, with detectable declines frequently preceding official bans, suggesting the influence of progressive restrictions or shifts in agricultural practices. In contrast, PFAS profiles display more complex dynamics: legacy compounds such as perfluorooctanesulfonic acid and its precursors peaked in the early 2000s, after which their decline was offset by the increasing presence of alternative substances (e.g., fluorotelomersulfonic acids, betaines), indicative of industrial substitution. Overall, sediment composition had a secondary influence on TrOC profiles, with external factors such as regulatory decisions and technological developments in wastewater treatment playing predominant roles. These findings underscore the utility of collecting and analyzing sedimentary archives for assessing the long-term effectiveness of environmental policies and for identifying persistent and emerging contaminants in riverine systems.
(Journal of Environmental Management. vol. 389, n° 0301-4797, pp. 126276, 03/09/2026)
METIS, EPHE, PSL, INSU - CNRS, SU, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, GEDI, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, LEHNA, UCBL, ENTPE, 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, 03/09/2026)
BOREA, MNHN, IRD, SU, CNRS, UA, GEOMAR, CCMAR, UAlg, 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, 03/09/2026)
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, 03/09/2026)
CEREGE, IRD, AMU, CdF (institution), INSU - CNRS, CNRS, INRAE, 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, 03/09/2026)
EPHE, PSL, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
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.
(03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, AWI, AWI
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.
(03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, AWI, AWI
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.
(03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS