Monsoon-driven Saharan dust variability over the past 240,000 years
Reconstructions of past Saharan dust deposition in marine sediments provide foundational records of North African climate over time scales of 10(3) to 10(6) years. Previous dust records show primarily glacial-interglacial variability in the Pleistocene, in contrast to other monsoon records showing strong precessional variability. Here, we present the first Saharan dust record spanning multiple glacial cycles obtained using Th-230 normalization, an improved method of calculating fluxes. Contrary to previous data, our record from the West African margin demonstrates high correlation with summer insolation and limited glacial-interglacial changes, indicating coherent variability in the African monsoon belt throughout the late Pleistocene. Our results demonstrate that low-latitude Saharan dust emissions do not vary synchronously with high-and mid-latitude dust emissions, and they call into question the use of existing Plio-Pleistocene dust records to investigate links between climate and hominid evolution.
(Science Advances. vol. 5, n° 2375-2548, pp. eaav1887, 01/09/2026)
GEOPS, UP11, CNRS, EAPS, MIT, MIT, LDEO, UdeC, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Shaping adaptive governance in estuarine cities Bordeaux Metropole and Gironde estuary facing global change
URBEST research project examine emergent adaptive governance in estuarine cities in a context of climate change.
(pp. 12, 01/09/2026)
UR ETBX, IRSTEA, UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Plant interactions shape pollination networks via nonadditive effects
Plants grow in communities where they interact with other plants and with other living organisms such as pollinators. On the one hand, studies of plant–plant interactions rarely consider how plants interact with other trophic levels such as pollinators. On the other, studies of plant–animal interactions rarely deal with interactions within trophic levels such as plant–plant competition and facilitation. Thus, to what degree plant interactions affect biodiversity and ecological networks across trophic levels is poorly understood. We manipulated plant communities driven by foundation species facilitation and sampled plant–pollinator networks at fine spatial scale in a field experiment in Sierra Nevada, Spain. We found that plant–plant facilitation shaped pollinator diversity and structured pollination networks. Nonadditive effects of plant interactions on pollinator diversity and interaction diversity were synergistic in one foundation species networks while they were additive in another foundation species. Nonadditive effects of plant interactions were due to rewiring of pollination interactions. In addition, plant facilitation had negative effects on the structure of pollination networks likely due to increase in plant competition for pollination. Our results empirically demonstrate how different network types are coupled, revealing pervasive consequences of interaction chains in diverse communities.
(Ecology. vol. 100, n° 0012-9658, pp. e02619, 01/09/2026)
UZH, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UNIROMA, UAL, OUMNH, LSV Angers, LSV, ANSES, UNIBO
Correlating three centuries of historical and geological data for the marine deposit reconstruction of two depositional environments of the French Atlantic coast
This paper details a high-resolution record of French Atlantic coast extreme wave events using a multi-proxy analysis of dated sedimentary deposits. Two lagoons 1) the Petite Mer de Gâvres and 2) the Traicts du Croisic were chosen to identify damaging storm events from the last 300 years with Beeker sampling, 210Pb and 137Cs dating and sedimentary analysis. Using two new geochemical proxies in the French Atlantic coast, Sr/Fe and Ca/Ti, shows that several storminess events are reported in the nine cores drilled. By correlation with historical archives, seven major storms are confirmed: 1924 CE, 1940 CE, 1972 CE, 1977 CE, 1990 CE, 1999 CE, and an 1896 CE highly damaging event. Four other XIXth and XVIIIth century extreme wave event correlations are also proposed from this multi-proxy analysis: 1775 CE, 1811 CE, 1838 CE and 1876 CE. Societal and natural impacts caused by these coastal floods are revealed using our dense and varied historical archives.
(Marine Geology. vol. 407, n° 0025-3227, pp. 181-191, 01/09/2026)
OSUNA, UA, UN UFR ST, UN, IFSTTAR, INSU - CNRS, Cnam, CNRS, IMT Atlantique, IMT, LETG - Nantes, UNICAEN, NU, EPHE, PSL, UBO EPE, UR2, CNRS, IGARUN, UN, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Editorial for the Special Issue "Remote Sensing in Coastal Zone Monitoring and Management-How Can Remote Sensing Challenge the Broad Spectrum of Temporal and Spatial Scales in Coastal Zone Dynamic?
Coastal zones are sensitive areas responding at various scales (events to long-term trends) where the monitoring and management of physico-chemical, biological, morphological processes, and fluxes are highly challenging. They are directly affected by anthropization (urbanization, industrialization, agri-and aquaculture) and climate change (e.g., river discharges, waves, sea-level rise). Coastal waters only represent 15% of the global ocean, but concentrate 90% of commercial fisheries, contribute to 25% of global biological productivity, and represent 80% of the marine biodiversity, while being associated with an intensive tourism-related economy. The monitoring and management of coastal zones require past, present, and future observations adapted to quite diverse and dynamic environments. To complement field measurements, the use of remote sensing data provides useful information to map the hydromorphological (freshwater discharge, currents, shoreline evolution), physico-chemical (water transparency, temperature, salinity, oxygen, nutrients, and pollutants), and biological (habitats, phytoplankton blooms) properties of the coastal zones. This special issue highlights how the monitoring of coastal zones benefits from both long-term (~40 years) and recent capabilities of remote sensing observations. It also provides new methodologies to optimize the combined use of multi-mission satellite/airborne data and field measurements for an integrated approach. Considering different types of coastal environments (bays, estuaries, sandy and muddy systems), several key land and water quality (vegetation, temperature, concentrations of suspended particulate matter and polychlorinated biphenyl, aquatic plants) and morphological (shorelines, mudbanks, wetlands) parameters can be remotely sensed at various spatial and temporal scales, using innovative methods and providing validated products.
(Remote Sensing. vol. 11, n° 2072-4292, pp. 1028, 01/09/2026)
LOV, INSU - CNRS, SU, CNRS, IMEV, INSU - CNRS, SU, CNRS, EBD, CSIC, IAFE, CONICET, UBA, CSIRO, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
EStimating Contaminants tRansfers Over Complex food webs (ESCROC): An innovative Bayesian method for estimating POP's biomagnification in aquatic food webs
Pollution greatly impacts ecosystems health and associated ecological functions. Persistent Organic Pollutants (POPs) are among the most studied contaminants due to their persistence, bioaccumulation, and toxicity potential. Biomagnification is often described using the estimation of a Trophic Magnification Factor (TMF). This estimate is based on the relationship between contamination levels of the species and their trophic level. However, while the estimation can be significantly biased in relation to multiple sources of uncertainty (e.g. species physiology, measurement errors, food web complexity), usual TMF estimation methods typically do not allow accounting for these potential biases. More accurate and reliable assessment tool of TMFs and their associated uncertainty are therefore needed in order to appropriately guide chemical pollution management. The present work proposes a relevant and innovative TMF estimation method accounting for its many variability sources. The ESCROC model (EStimating Contaminants tRansfers Over Complex food webs), which is implemented in a Bayesian framework, allows for a more reliable and rigorous assessment of contaminants trophic magnification, in addition to accurate estimations of isotopes trophic enrichment factors and their associated uncertainties in food webs. Similar to classical mixing models used in food web investigations, ECSROC computes diet composition matrices using isotopic composition data while accounting for contamination data, leading to more robust food web descriptions. As a demonstration of the practical application of the model, ESCROC was implemented to revisit the trophic biomagnification of 5 polyfluoroalkyl substances (PFAS) in a complex estuarine food web (the Gironde, SW France). In addition to the TMF estimate and 95% confidence intervals, the model provided biomagnification probabilities associated to the investigated contaminants.
(Science of the Total Environment. vol. 658, n° 0048-9697, pp. 638-659, 01/09/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LPTC, UB, CNRS, ISM, UB, INC-CNRS, CNRS
Environmental fate of chlordecone in coastal habitats: recent studies conducted in Guadeloupe and Martinique (Lesser Antilles)
The organochlorine pollution by chlordecone, an insecticide spread in the past in banana plantations, is now recognized as a major ecological, economic and social crisis in Guadeloupe and Martinique Islands. Due to its physical and chemical properties, this molecule is particularly persistent in the natural environment. Volcanic soil of Guadeloupe and Martinique contain allophanes (amorphous clays), which favor chlordecone trapping due to their structure and physical properties. Thus, with this trapping ability, allophanes could constitute a vector allowing chlordecone to contaminate runoff waters, and finally the sea. In the present publication, several studies recently conducted in the Lesser Antilles have been compiled in order to evaluate the desorption of chlordecone from allophanes when arriving in the estuarine environment and to determine the transfer of chlordecone along marine trophic food webs. The experiments showed that 20% of the initial quantity of chlordecone was released from allophones in estuarine conditions and 10% in marine environment. These results could explain the high level of contamination found in the suspended organic matter and zooplankton in the coastal areas located downstream the contaminated watersheds. The contamination of the marine food webs of mangroves seagrass beds and coral reefs, is dominated by a contamination 'by bath" in littoral waters containing chlordecone and by bioamplification seawards.
(Environmental Science and Pollution Research, n° 0944-1344, 01/09/2026)
BOREA, UNICAEN, NU, MNHN, IRD, SU, CNRS, UA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IFREMER, ISM, UB, INC-CNRS, CNRS, ULiège
Intratidal and Subtidal Circulation in a Tropical Estuary during Wet Season: The Maroni, French Guiana
Observations of water level, current velocity, river discharge, wind and salinity were collected in the Maroni estuary, on the border of French Guiana and Suriname during the wet season of 2018 to explore subtidal circulation patterns. Measurements are complimented by the application of analytical models with an aim to diagnose forcing mechanisms responsible for producing subtidal flows during the day of data collection and to extrapolate these findings to other time periods with variable wind and river forcing. Subtidal along-channel flows were found to be dominated by river discharge, with seaward directed velocities found throughout the channel section reaching 40 cm s −1. This pattern was altered with strong southwesterly winds, which produced and inverse gravitational circulation pattern despite the elevated river discharge. Secondary, or cross-channel flows, displayed a three-layer vertical structure in the main channel due to a combination of channel curvature and tidal asymmetry in the lateral baroclinic pressure gradient. The pressure gradient was produced by a salinity intrusion front that only manifested in the channel during flood tide. This is the first comprehensive study of tidal and subtidal flow dynamics in the Maroni estuary.
(Journal of Marine Science and Engineering. vol. 7, n° 2077-1312, pp. 433, 01/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEEISA, IFREMER, UG, CNRS, M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS
Impact of diuron and S-metolachlor on the freshwater diatom Gomphonema gracile: Complementarity between fatty acid profiles and different kinds of ecotoxicological impact-endpoints
Fatty acids (FA) are crucial for the maintenance of membrane fluidity and play a central role in metabolic energy storage. Polyunsaturated fatty acids play an essential ecological role since they are key parameters in the nutritional value of algae. Pesticide impacts on fatty acid profiles have been documented in marine microalgae, but remain understudied in freshwater diatoms. The aims of this study were to: 1) investigate the impact of diuron and S-metolachlor on "classical descriptors" (photosynthesis, growth rate, pigment contents, and on the expression levels of target genes in freshwater diatoms), 2) examine the impact of these pesticides on diatom fatty acid profiles and finally, 3) compare fatty acid profiles and "classical descriptor" responses in order to evaluate their complementarity and ecological role. To address this issue, the model freshwater diatom Gomphonema gracile was exposed during seven days to diuron and S-metolachlor at 10 µg.L.
(Science of the Total Environment. vol. 688, n° 0048-9697, pp. 960-969, 01/09/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LBM, UB, CNRS
Mécanismes : échanges de polluants aux interfaces sol-végétation-atmosphère et devenir dans l’atmosphère
(pp. 73-106, 01/09/2026)
ECOSYS, INRA, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, SADAPT, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS