Sustainability ranking of antifouling coatings for leisure boats – Balancing efficacy and environmental impact
Antifouling coatings are widely used on leisure boats to prevent biofouling, yet their environmental impacts vary significantly depending on formulation. This study systematically evaluated seven commercial antifouling products, including five copper-based coatings (with varying cuprous oxide content), one tralopyril-based coating and one biocide-free silicone foul-release coating. The evaluation included three complementary approaches: field-based efficacy testing, environmental risk assessment (ERA) modeling and ecotoxicological assays. Field trials were conducted over six months at three European coastal sites (Skagerrak, Kattegat and Atlantic) to assess the antifouling performance. Biocide release rates were quantified using X-ray Fluorescence and used to model environmental risks in accordance with EU guidelines. Acute toxicity of leachates was tested on four marine species (Aliivibrio fischeri, Phaeodactylum tricornutum, Artemia salina larvae and Oryzias melastigma larvae). The biocide-free silicone coating ranked highest in sustainability, combining strong antifouling efficacy with minimal acute toxicity. The copper-based coatings typically showed comparable efficacy at all sites despite differences in copper release but some only passed ERA thresholds in one of the sites (Atlantic). Lower copper content formulations generally exhibited reduced environmental impact. The tralopyril-based coating, despite being marketed as “environmentally safe”, demonstrated the highest toxicity and environmental risk. These findings highlight the need for environmental assessment of antifouling products to validate environmental safety claims and to promote lower impact formulations. While ERA modeling is suitable for biocidal products, ecotoxicological testing remains essential for biocide-free alternatives. Improved and standardized leaching protocols are needed to better reflect real-world conditions and support sustainable product development.
(Journal of Hazardous Materials. vol. 506, n° 0304-3894, pp. 141600, 03/09/2026)
OFB, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GU, DTU, UMR MARBEC, IRD, IFREMER, CNRS, UM
Rapport d’activité ODATIS 2025
Le pôle ODATIS de l'IR Data Terra publie son rapport d'activités 2025, qui synthétise les activités et les actions menées durant l'année passée à l'échelle du pôle, de ses Centres de Données et Services et au travers de son implication dans différents projets nationaux et européens et dans les instances de l'IR Data Terra. Ce rapport témoigne de l'intensité de l'activité du pôle, des résultats accomplis, des développements en cours, de l'évolution de l'offre des données, outils et services qui représentent autant un bilan qu'un fil stratégique pour mieux cibler, fédérer et coordonner les besoins de la communauté océanographique et de l'observation de la Terre.
(03/09/2026)
IRSI, IFREMER, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, OMP, IRD, INSU - CNRS, CNES, CNRS, EPE UT, Comue de Toulouse, IUEM, IRD, INSU - CNRS, UBO EPE, CNRS, IFREMER, UQAR, UBO EPE, LOV, INSU - CNRS, SU, CNRS, IMEV, INSU - CNRS, SU, CNRS, ENTROPIE [Nouvelle-Calédonie], IRD [Nouvelle-Calédonie], IFREMER, UNC, CNRS, IRD, CNRS, IRD, IFREMER, INSU - CNRS, IGN, CNRS, CNES, INRAE, CNES, FR2424, SBR, SU, CNRS, SBR, SU, CNRS, ABIMS, FR2424, SBR, SU, CNRS, LOPS, IRD, IFREMER, INSU - CNRS, UBO EPE, CNRS, SHOM, MIO, IRD, AMU, INSU - CNRS, UTLN, CNRS, OSU PYTHEAS, IRD, AMU, INSU - CNRS, CNRS, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Faire face aux polluants éternels
(03/09/2026)
LEESU, UPEC UP12, ENPC, IP Paris, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
The Ediacaran volcanoclastic system of the Western Anti-Atlas (Morocco): Record of a rift – post-rift transition
The Upper Neoproterozoic volcano-sedimentary series are spectacularly exposed in the Anti-Atlas mountain ranges in Morocco. They offer a unique window into the tectonic-sedimentary and volcanic processes active during the transition between a rifting phase and a post-rift phase. In this context, our study aims to reconstruct the evolution of paleotopographies, and more specifically Ediacaran paleoreliefs, in order to understand the tectonic and volcanic processes responsible for their formation, as well as the mechanisms that have favored their preservation. Field observations within the inliers of the Western Anti-Atlas (Kerdous, Tagragra d'Akka, Aït Abdallah, Alma) have made it possible to recognize the nature and architecture of the last syn-rift series (Ouarzazate Group/PIII) and the post-rift ones (Adoudou Formation) of the Upper Neoproterozoic-Cambrian, as well as the syn-sedimentary tectonic structures that control them. In general, the rifting process begins with the activation of normal faults of variable directions, quickly followed by predominantly rhyolitic volcanism, whose deposits and lava flows are preserved in local tectonic depressions. Significant paleoreliefs become then apparent along the fault scarps. This pronounced paleotopography led to the formation of lacustrine fan-delta systems, recorded by large prisms of breccia deposits that quickly evolved to silty-carbonate facies in the axis of the newly formed depressions. These sedimentary or volcanosedimentary deposits gradually fossilize the paleoreliefs in a more homogeneous subsidence regime with reduced fault activity. A regional decrease in subsidence at the end of the rifting process is interpreted as the filling of the tectono-sedimentary systems, resulting in a flattened continental paleotopography. It was on this flattened paleosurface that the rise in relative sea level in the post-rift context led to the transgression of the peritidal platform deposits with microbial carbonate production of the Adoudou Formation at the Neoproterozoic-Cambrian transition. All of these series were then slightly deformed during the Hercynian orogeny to acquire their current arrangement in the Anti-Atlas inliers, without these appearing to be significantly influenced by the Neoproterozoic structures.
(. vol. 85, 03/09/2026)
ENSEGID, Bordeaux INP, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, BRGM, ISTO, BRGM, INSU - CNRS, UO, CNRS, ISTO, BRGM, INSU - CNRS, UO, CNRS
Influence of Estuarine Turbidity Maximum Dynamics and River Discharge on Tide Propagation in Two Fluvial-Estuarine Systems
Tidal propagation in estuaries is shaped by the balance between morphological convergence and frictional effects, yet the influence of mud deposition associated with estuarine turbidity maxima remains unexplored. This study investigates the influence of Estuarine Turbidity Maxima (ETM) dynamics and river discharge on tidal propagation in the Loire and Gironde estuaries, combining frequency analysis of high-frequency observational data with an analytical model. Enhanced Harmonic Analysis reveals a tipping section-located downstream of the saline intrusion limit-in both hyperturbid systems, beyond which tidal properties (amplification, distortion, asymmetry) become highly sensitive to river discharge. Decomposing total friction into tidal, riverine, and interaction terms shows that the tipping point marks a regime shift where tide-river interaction dominates under low flow conditions, while the river term dominates during high discharge. Observations show that seasonal and interannual ETM-induced changes in bottom roughness can modulate tidal amplification by up to 35%, a mechanism confirmed by idealized modelling, while morphological changes have a more limited effect at these scales. Finally, scenario-based simulations suggest that sealevel rise and anthropogenic deepening may further enhance tidal amplification, 1 potentially promoting the upstream migration of salinity and turbidity maxima, with broader implications for estuarine functioning under future climate and human pressures.
(Estuaries and Coasts. vol. 49, n° 1559-2723, pp. 68, 03/09/2026)
RHITME, Cerema, M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LOMA, UB, CNRS
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 high-resolution, 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)
(. vol. 41, pp. 10 - 15, 03/09/2026)
BRGM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CEFREM, UPVD, INSU - CNRS, CNRS, ONF
Past Ocean surface density from planktonic foraminifera calcite δ18O
Density of seawater is a critical property that controls ocean dynamics. Previous works suggest the use of the δ18O calcite of foraminifera as a potential proxy for paleodensity. However, potential quantitative reconstructions were limited to the tropical and subtropical surface ocean and without an explicit estimate of the uncertainty in calibration model parameters. We developed the use of the δ18Oc of planktonic foraminifera as a surface paleodensity proxy using Bayesian regression models calibrated to annual surface density. Predictive performance of the models improves when we account for inter-species specific differences. We investigate the additional uncertainties that could be introduced by potential evolution of the δ18Oc-density relationship with time – from the last glacial maximum (LGM) to the preindustrial (PI) – through the combination of past isotope enabled climate model simulations and a foraminiferal growth module. We demonstrate that additional uncertainties are weak globally, except for the Nordic Seas region. We applied our Bayesian regression model to LGM and Late Holocene (LH) δ18Oc foraminifera databases to reconstruct annual surface density during these periods. We observe stronger LGM density value changes at low latitudes compared to mid latitudes. These results will be used to evaluate numerical climate models in their ability to simulate ocean surface density during the extreme climatic period of the LGM. The new calibration has great potential to reconstruct the past temporal evolution of ocean surface density over the Quaternary. Under climates outside the Quaternary period and in ocean basins characterized by anti-estuary circulation, like the current Mediterranean Sea and Red Sea, our calibration could provide density estimates with larger uncertainty, a point that requires further investigations.
(Climate of the Past. vol. 22, n° 1814-9324, pp. 247-263, 03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ICM, CSIC, CRM, UAB, AWI, LOCEAN, MNHN, IRD, INSU - CNRS, SU, CNRS, IPSL (FR_636), ENS-PSL, PSL, UVSQ, CEA, INSU - CNRS, X, IP Paris, CNES, SU, CNRS, UPCité, VU, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, CLIM, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA
Wave Input-Reduction for Shoreline Modelling of a High-Energy Environment with Complex Geological Settings
The long-term (decades) evolution of shoreline change along coastline (O(15)Km) with complex offshore wave transformation challenges both, state of the art process-based morphodynamics and reduce-complexity shoreline models. A major limitation is the computational time required to simulate the detailed spatiotemporal evolution of the wave field, particularly in regions where offshore wave refraction induces localized energy focusing. This study focuses on a 15-Km sandy coast on the North Medoc, southwestern France, characterized by high-energy, macro-tidal conditions, severe erosion, and complex offshore bathymetry. Effective coastal management strategies for the coming decades require the implementation of a reduced-complexity (RC) shoreline model. However, oversimplification of wave transformations in such a complex hydro-morphodynamic environment can result in flawed predictions of alongshore wavebreaking parameters and, consequently, shoreline change. Thus, a full wave propagation model is required, but computational time reduction techniques must be implemented to minimize computational cost. To address these challenges, this study introduces an easy-to-apply input reduction (IR) methodology that integrates offshore wave clustering to reduce computational costs when modeling long-term shoreline change within RC shoreline models.
(. vol. 42, pp. 652-658, 03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, BRGM
Non-stationary Model Free Parameter in Equilibrium Shoreline Modelling
The state-of-the-art equilibrium shoreline model proposed ShoerFor [1] is used to hindcast shoreline evolution. A similar approach to the work of Ibaceta et al. (2022) [2] is adopted, where they introduced non-stationary model free parameters to improve long term shoreline change predictions. An Ensemble Kalman Filter (EnKF) is implemented to track the temporal variability in model free parameters and explore if their evolution can be linked to the environmental forcing. A correlation between the winter wave energy and the model free parameter φ (beach memory) is identified where high energetic winters are followed by an increase in the parameter suggesting such time variation in beach memory can be parametrized.
(. vol. 42, pp. 646 - 651, 03/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, BRGM, UNSW
Past trajectory of a Northwest Europe socio-ecosystem at the land-sea interface: Case study of the northern watersheds of the Bay of Brest over the last 150 years
The Bay of Brest (BB) is a macro-tidal estuarine environment that has been exposed to strong anthropogenic pressures over the past few decades, especially since the Second World War. This makes the BB an ideal site for studying coastal ecosystem transformations since the Industrial Revolution. We analysed five sediment cores collected in two key BB areas with varying exposure to marine hydrodynamic processes: i) the Elorn sector (3 cores) and ii) the Bay of Daoulas (2 cores) in the inner BB, close to the mouth of the Daoulas river. Our study used palynological (pollen and dinoflagellate cysts) and benthic foraminiferal assemblages, sedimentological data, and elemental geochemistry, at a very fine temporal resolution (2 to 16-year resolution). Working at a local spatial scale reveals robust correlations between the different driving forces and environmental changes over the last 150 years. Statistical analyses of these sedimentological and paleoecological time series reveal major breakpoints, specifically four key threshold periods: 1925–1938, 1960–1967, 1980–1987, and 2005, which are essential for understanding temporal changes in protist communities and the evolution of BB landscapes over this time period. Combining these findings with a reanalysis of regional precipitation patterns back to 1850, nutrient concentration data, and historical accounts of land-use practices, enables us to identify the main drivers of coastal ecosystem transformation. Our findings emphasize the strong influence of agricultural practices on trophic changes and the decline in the BB water quality, in agreement with coastal observatory series showing a notable increase in toxic algal blooms since the 1980s.
(Palaeogeography, Palaeoclimatology, Palaeoecology. vol. 690, n° 0031-0182, pp. 113703, 03/09/2026)
GEO-OCEAN, UBS, IFREMER, INSU - CNRS, UBO EPE, CNRS, BEEP, IFREMER, UBO EPE, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GEOARCHI, UBS, UBO EPE, IBSHS, UBO EPE, ENS Rennes, GR, UR, INSU - CNRS, CNRS, LEMAR, IRD, IFREMER, UBO EPE, CNRS, LMBA, UBS, UBO EPE, CNRS