Projet Phytosol Résidus de pesticides dans les sols français : présence, risques et persistance
À la différence de ce qui est fait pour les milieux aquatiques et l'atmosphère, la surveillance de la contamination des sols par les pesticides n'existe pas à l'échelle du territoire. Or, des travaux récents de chercheurs INRAE, en collaboration avec l'université de Bordeaux, montrent qu'un grand nombre de substances, en quantité importante, y persistent sous forme de résidus. Des résultats parus dans la revue Environmental Science & Technology.
(04/12/2023)
Info&Sols, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR ISPA, Bordeaux Sciences Agro, INRAE, LAS, INRAE
Influence d’une structure anticlinale dans les modalités d’échanges et de recharge d’un système multicouche : l’exemple du système aquifère du Cénomanien dans le Sud de la Gironde (France)
(Géologues, n° 0016-7916, pp. p 17-22, 04/12/2023)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, SMEGREG, BRGM
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre
Due to large northward heat transport, the Atlantic meridional overturning circulation (AMOC) strongly affects the climate of various regions. Its internal variability has been shown to be predictable decades ahead within climate models, providing the hope that synchronizing ocean circulation with observations can improve decadal predictions, notably of the North Atlantic subpolar gyre (SPG). Climate predictions require a starting point which is a reconstruction of the past climate. This is usually performed with data assimilation methods that blend available observations and climate model states together. There is no unique method to derive the initial conditions. Moreover, this can be performed using full-field observations or their anomalies superimposed on the model's climatology to avoid strong drifts in predictions. How critical ocean circulation drifts are for prediction skill has not been assessed yet. We analyze this possible connection using the dataset of 12 decadal prediction systems from the World Meteorological Organization Lead Centre for Annual-to-Decadal Climate Prediction. We find a variety of initial AMOC errors within the predictions related to a dynamically imbalanced ocean states leading to strongly displaced or multiple maxima in the overturning structures. This likely results in a blend of what is known as model drift and initial shock. We identify that the AMOC initialization influences the quality of the SPG predictions. When predictions show a large initial error in their AMOC, they usually have low skill for predicting internal variability of the SPG for a time horizon of 6-10 years. Full-field initialized predictions with low AMOC drift show better SPG skill than those with a large AMOC drift. Nevertheless, while the anomaly-initialized predictions do not experience large drifts, they show low SPG skill when skill also present in historical runs is removed using a residual correlation metric. Thus, reducing initial shock and model biases for the ocean circulation in prediction systems might help to improve their prediction for the SPG beyond 5 years. Climate predictions could also benefit from quality-check procedure for assimilation/initialization because currently the research groups only reveal the problems in initialization once the set of predictions has been completed, which is an expensive effort.
(Frontiers in Climate. vol. 5, n° 2624-9553, 04/12/2023)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, MOHC, UHH, CEN, UHH, GFI / BiU, UiB, UCAS, CAS, UCAR, GFDL, NOAA, CMCC, MPI-M, BSC-CNS, DMI, CCCma, ECCC, JAMSTEC, MRI, JMA
Archives sédimentaires : reconstruire les trajectoires temporelles des contaminants
(pp. Dans Baratelli, F., Thiebault, T. (eds), Dynamique des contaminants à l'échelle du bassin versant de la Seine, PIREN-Seine, Rapport de synthèse phase VIII, Volume 9, 2023, pp. 4-34, 01/12/2023)
METIS, EPHE, PSL, INSU - CNRS, SU, CNRS, EPHE, PSL, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GERS-LEE, GéHCO, UT, GEDI, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA
Is part-night lighting a suitable mitigation strategy to limit Artificial Light at Night effects on the biological rhythm at the behavioral and molecular scales of the oyster Crassostrea gigas?
(Science of the Total Environment. vol. 905, n° 0048-9697, pp. 167052, 01/12/2023)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Microscopic charcoals in ocean sediments off Africa track past fire intensity from the continent
Abstract Fires in Africa account for more than half of global fire-carbon emissions but the long-term evolution of fire activity and its link to global climate change remains elusive. Paleofire records provide descriptive information about fire changes through time, going beyond the range of satellite observations, although fire regime characteristics are challenging to reconstruct. To address this conceptual gap, we report here the abundance and morphometric data for a large set of microscopic charcoal samples ( n = 128) recovered from surface ocean sediments offshore Africa. We show that in subtropical Southern Africa, large and intense fires prevailing in open savanna-grassland ecosystems produce a high abundance of small and elongated microcharcoal particles. In contrast, in the forest ecosystems of equatorial and tropical regions of western and central Africa, low-intensity fires dominate, producing low amounts of squared microcharcoal particles. Microcharcoal concentration and morphotype in marine sediment records off Africa are thus indicative of fire regime characteristics. Applied to down-core marine charcoal records, these findings reveal that at orbital time-scale intense and large, open grassland-savanna fires occurred during wet periods in the sub-tropical areas. A strong contribution of fire carbon emissions during periods of precession and summer insolation maxima in the geological record is thus expected.
(Communications Earth & Environment. vol. 4, n° 2662-4435, pp. 133, 01/12/2023)
USV, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CEFE, UPVM, EPHE, PSL, CNRS, IRD [Occitanie], INRAE, Institut Agro, UM, IMBE, AU, AMU, CNRS, GEO-OCEAN, UBS, IFREMER, INSU - CNRS, UBO EPE, CNRS, MARUM
Les bassins carbonifères-permiens du sud du Bassin parisien et du nord du Massif central
Les bassins carbonifères-permiens du nord du Massif central sont connus historiquement en raison de leurs ressources carbonées (charbon, huiles bitumineuses), raison pour laquelle ils ont été largement étudiés jusque dans les années 1980, avec notamment la fin de l’exploration en France.
(Géochronique. vol. 168, n° 0292-8477, pp. 41-49, 01/12/2023)
BRGM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, GR, UR, INSU - CNRS, CNRS, BGS, UB, CNRS
Relative contribution of canopy and soil effects between plants with different metal tolerance along a metal pollution gradient
(Science of the Total Environment. vol. 904, n° 0048-9697, pp. 166905, 01/12/2023)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Tritiated thymidine induces developmental delay, oxidative stress and gene overexpression in developing zebrafish (Danio rerio)
Tritium is a betta emitter radionuclide. Being an isotope of hydrogen, it is easily transferred to different environmental compartments, and to human and non-human biota. Considering that tritium levels are expected to rise in the upcoming decades with the development of nuclear facilities producing tritium using fission processes, investigating the potential toxicity of tritium to human and non-human biota is necessary. Tritiated thymidine, an organic form of tritium, has been used in this study to assess its toxicity on fish embryo development. Zebrafish embryos (3.5 hpf; hours post fertilization) have been exposed to tritiated thymidine at three different activity concentrations (7.5; 40; 110 kBq/mL) for four days. These experiments highlighted that zebrafish development was affected by the exposure to organic tritium, with smaller larvae at 3 dpf after exposure to the two lowest dose rates (22 and 170 µGy/h), a delayed hatching after exposure to the two highest dose rates (170 and 470 µGy/h), an increase in the spontaneous tail movement (1 dpf) and a decrease in the heartbeat (3 dpf) after exposure to the highest dose rate. The results also highlighted an increase in ROS production in larvae exposed to the intermediate dose rate. A dysregulation of many genes, involved in apoptosis, DNA repair or oxidative stress, was also found after 1 day of exposure to the lowest tritium dose rate. Our results thus suggest that exposure to tritiated thymidine from a dose rate as low as 22 µGy/h can lead to sublethal effects, with an effect on the development, dysregulation of many genes and increase of the ROS production. This paper provides valuable information on toxic effects arising from the exposure of fish to an organic form of tritium, which was the main objective of this study.
(Aquatic Toxicology. vol. 265, n° 0166-445X, pp. 106766, 01/12/2023)
IRSN/PSE-ENV/SERPEN/LECO, IRSN/PSE-ENV/SERPEN, IRSN, IRSN/PSE-SANTE/SDOS/LDRI, IRSN/PSE-SANTE/SDOS, IRSN, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
First assessment of Rare Earth Element organotropism in Solea solea in a coastal area: The West Gironde Mud Patch (France)
Few studies exist on bioaccumulation and internal distribution of Rare Earth Elements (REEs) in marine fishes. REEs organotropism was determined in common sole (Solea solea) from the West Gironde Mud Patch (WGMP; N-E Atlantic Coast, France). The highest REEs concentrations occurred in liver (213 ± 49.8 µg kg -1 DW) and gills (119 ± 77.5 µg kg -1 DW) followed by kidneys (57.7 ± 25.5 µg kg -1 DW), whereas the lowest levels were in muscles (4.38 ± 1.20 µg kg -1 DW) of Solea solea. No significant age-or sex-related differences were observed.
The organotropism varied among groups of REEs. Light and heavy REEs preferentially accumulated in liver and gills, respectively. All considered organs showed different normalized REEs patterns, suggesting differences in internal distribution processes between organs. Further work should address: (1) baseline levels worldwide, and (2) factors controlling uptake and organ-specific bioaccumulation of REEs.
(Marine Pollution Bulletin. vol. 197, n° 0025-326X, pp. 115730, 01/12/2023)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CNRS, Bordeaux INP, CCEM, IFREMER