Climate variability of the last five isotopic interglacials: Direct land-sea-ice correlation from the multiproxy analysis of North-Western Iberian margin deep-sea cores
(pp. 375-386 (chapter 25), 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, PALEOCEAN, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA
Influence of the parasite worm Polydora sp. on the behaviour of the oyster Crassostrea gigas: a study of the respiratory impact and associated oxidative stress
The aim of this study was to investigate how the worm Polydora sp., which induces oysters into creating mud blisters in response to an irritation within their shells, could interfere with the oyster Crassostrea gigas physiology and ethology. The impact was characterized by studying two groups of oysters (non-parasitized and parasitized) during a 30 days period: (1) the animal behaviour by analysing their valve activity (valvometry), and (2) the animal respiratory physiology by measuring in vivo the oxygen partial pressure and the specific oxygen consumption in selected tissues (heart, fast and slow adductor muscle). We also researched a putative impact on the expression of several oxidative stress genes at the heart level. Our results show that Polydora sp. is clearly an oyster’s parasite as it induces a decrease in oyster growth according to the infestation intensity. Moreover, it modifies the behaviour and the respiratory physiology of the molluscs. Infested animals opened more frequently but for less time and their level of blood oxygenation was systematically higher than healthy molluscs. These high levels of oxygenation had no effect on the oxidative metabolism of the tissues studied but they induced oxidative stress. Indeed, the superoxide dismutase gene showed a threefold increase in expression in the heart of infested oysters. A putative scenario of the weakening mechanism is proposed.
(Marine Biology. vol. 152, n° 0025-3162, pp. 329-338, 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Gas transfer velocities of CO2 and CH4 in a tropical reservoir and its river downstream
We have measured simultaneously the methane (CH4) and carbon dioxide (CO2) surface concentrations and water–air fluxes by floating chambers (FC) in the Petit-Saut Reservoir (French Guiana) and its tidal river (Sinnamary River) downstream of the dam, during the two field experiments in wet (May 2003) and dry season (December 2003). The eddy covariance (EC) technique was also used for CO2 fluxes on the lake. The comparison of fluxes obtained by FC and EC showed little discrepancies mainly due to differences in measurements durations which resulted in different average wind speeds. When comparing the gas transfer velocity (k600) for a given wind speed, both methods gave similar results. On the lake and excluding rainy events, we obtained an exponential relationship between k600 and U10, with a significant intercept at 1.7 cm h− 1, probably due to thermal effects. Gas transfer velocity was also positively related to rainfall rates reaching 26.5 cm h−1 for a rainfall rate of 36 mm h− 1. During a 24-h experiment in dry season, rainfall accounted for as much as 25% of the k600. In the river downstream of the dam, k600 values were 3 to 4 times higher than on the lake, and followed a linear relationship with U10.
(Journal of Marine Systems. vol. 66, n° 0924-7963, pp. 161-172, 26/10/2026)
LAERO, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LAERO, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNRS, CNRM, INSU - CNRS, CNRS, Comue de Toulouse, IREQ
Holocene long- and short-term climate changes off Adélie Land, East Antarctica
Diatom data from a marine sediment core give insight on Holocene changes in sea‐surface conditions and climate at high southern latitudes off Adélie Land, East Antarctica. The early to mid‐Holocene was warmer than the late Holocene with a transition at ∼4000 calendar years B. P. Sea ice was less present and spring‐summer growing season was greater during the warm period relative to the cold one, thus limiting sea ice diatom production and favoring more open ocean diatom to develop. The long‐term Holocene climatic evolution in East Antarctica is explained by a combination of a delayed response to local seasonal insolation changes coupled to the long memory of the Southern Ocean. Abrupt variations of the diatom relative abundances, indicating rapid climate changes, are superimposed to the Holocene long‐term trends. Spectral analyses calculate robust frequencies at ∼1600 a (where “a” is years), ∼1250 a, ∼1050 a, ∼570 a, ∼310 a, ∼230 a, ∼150–125 a, ∼110 a, ∼90 a, and ∼66 a. Such periods are very close to solar activity cyclicities, except for the periods at ∼310 a and ∼1250 a, which are close to internal climate variability cyclicities. Wavelet analyses estimate the same periods but indicate nonstationary cyclicities. Rapid climate changes at high southern latitudes may therefore be explained by a combination of external (solar) and internal (thermohaline circulation) forcings.
(Geochemistry, Geophysics, Geosystems. vol. 8, pp. n/a-n/a, 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, PROMES, UPVD, CNRS
Tidal modulation of wave-setup and wave-induced currents on the Aboré coral reef
As waves break on a reef, they create a radiation stress gradient that drives wave-setup and wave-induced currents. In this paper, tidally modulated wave-induced current and wave-setup are presented and analysed from field measurements performed on the Aboré coral reef in the southwest lagoon of New Caledonia. We show, in agreement with analytical models by Symonds et al (1995) and Hearn (1999), that this tidally modulated wave circulation is mainly controlled by the difference between the depth at the breakpoint and the water depth over the reef. A specific calibration of these models is proposed for the Aboré reef.
(Journal of Coastal Research. vol. Special Issue 50, n° 0749-0208, pp. 762 - 766 ICS2007, 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IRD [Nouvelle-Calédonie], ECOLA, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS
Dansgaard-Oeschger climatic variability revealed by fire emissions in southwestern Iberia
Paleoenvironmental records in Europe describing paleofires extending back to the Last Interglacial have so far been unavailable. Here we present paleofire results from the combined petrographic and automated image analysis of microcharcoal particles preserved in marine core MD95-2042 retrieved off southwestern Iberia and covering the last climatic cycle. The variability of microcharcoal concentrations reveals that the variability of fire emissions is mainly imprinted by the 23 000 yrs precessional cycle. A focus on the Last Glacial Period further shows that paleofires follow the variability of Dansgaard-Oeschger oscillation and Heinrich events and, therefore, parallel the variability of atmospheric temperatures over Greenland detected in ice cores. There is no evidence for fire increase related to human activity. The variability of fire emission by-products for the Last Glacial Period is interpreted in terms of changes in biomass availability. Low fire activity is associated with periods of drought which saw the development of semi-desert vegetation that characterised stadial periods. Fire activity increased during wetter interstadials, related to the development of open Mediterranean forests with more woody fuel availability.
(Quaternary Science Reviews. vol. 26, n° 0277-3791, pp. 1369-1383, 26/10/2026)
PACEA, UB, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CEREGE, IRD, INRA, AMU, CdF (institution), INSU - CNRS, CNRS, ISTO, INSU - CNRS, UO, CNRS, UCL-ASTR, UCLouvain
Inocula from activated sludge for ready biodegradability testing : Homogenization by preconditioning
(Chemosphere. vol. 68, n° 0045-6535, pp. 1447-1454, 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEFE, INEE-CNRS, CNRS, UT3, Comue de Toulouse, CNRS, Toulouse INP, Comue de Toulouse
Clay mineral composition of river sediments in the Amazon Basin
(CATENA. vol. 71, n° 0341-8162, pp. 340-356, 26/10/2026)
LMTG, UT3, Comue de Toulouse, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UnB
Comparative Evaluation of the Toxicity and Genotoxicity of Cadmium in amphibian larvae (Xenopus laevis and Pleurodeles waltl) Using the Comet Assay and tghe Micronucleus Test
The toxic and genotoxic potential of Cadmium (CdCl2) were evaluated by the micronucleus test (MNT) and comet assay (CA) using amphibian larvae (Xenopus laevis and Pleurodeles waltl). Acute toxicity results showed that Cd is toxic to Xenopus larvae exposed from 2 to 50 mg/L and to Pleurodeles from 5 to 50 mg/L, depending on the nature of the water (reconstituted water containing mineral salts or mineral water MW (Volvic®)). The MNT results obtained in MW showed that Cd (2 mg/L) is genotoxic to Xenopus, whereas it was not genotoxic to Pleurodeles at all concentrations tested. The CA established that the genotoxicity of Cd to Xenopus and Pleurodeles larvae depends on the concentration, the exposure times, and the comet parameters (Tail DNA, ETM, OTM, and TL). The CA and MNT results were compared for their ability to detect genotoxic effects, considering the concentrations of Cd applied and the exposure time. The CA showed Cd to be genotoxic from the first day of exposure. In amphibians, the CA appears to be a sensitive and suitable method for detecting genotoxicity such as that caused by Cd.
(Environmental Toxicology. vol. 22, n° 1520-4081, pp. 422-435, 26/10/2026)
LEFE, INEE-CNRS, CNRS, UT3, Comue de Toulouse, CNRS, Toulouse INP, Comue de Toulouse, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IRIT-SC, IRIT, UT Capitole, Comue de Toulouse, UT2J, Comue de Toulouse, UT3, Comue de Toulouse, CNRS, Toulouse INP, Comue de Toulouse, TMBI, UT2J, UT3, Toulouse INP, Comue de Toulouse, TESA, CBD, UT3, Comue de Toulouse, CNRS, CBI, UT3, Comue de Toulouse, CNRS, LSE-ENTPE, ENTPE, ENTPE, ENTPE
Parasite co-infection of two sympatric bivalves, the Manila clam (Ruditapes philippinarum) and the cockle (Cerastoderma edule) along a latitudinal gradient
Among the potential biotic factors affecting population dynamics, parasitism has received relatively little attention. The purpose of this study was to inventory marine bivalve parasites and to investigate relations between different parasite communities. Five intertidal stations along the French Atlantic shore were studied between Brittany and Arcachon Bay. Two bivalves (the edible cockle, Cerastoderma edule, and the Manila clam, Ruditapes philippinarum) were sampled and examined. The parasites included a bacterium (Vibrio tapetis), a protozoan (Perkinsus sp.), and digenetic trematode metacercariae (10 species). Perkinsus sp. prevalence and density in clams were higher than those measured in cockles (30 250 vs. 36 cells g−1 of gill wet weight, respectively) while digeneans were more common in cockles (46 metacercariae per cockle host vs. 1 per clam host). Distributions of digeneans and Perkinsus sp. were similar along the Atlantic shore. However, at each sampling station and at the individual scale, no correlation between Perkinsus sp. and digenean abundance was detected. These results suggest different ecological niches used by these two parasites within a community of bivalves but a similar response to environmental factors such as temperature and salinity. Vibrio tapetis was found at relatively high prevalence in all stations for both bivalve species (from 17% to 43% in cockles and from 23% to 50% in clams), but was associated with a low prevalence of Brown Ring Disease (BRD), a shell disease caused by this pathogen. No statistically significant relationship of these parasitic bacteria with trematodes and Perkinsus sp. was evidenced in the present study.
(Aquatic Living Resources. vol. 20, n° 0990-7440, pp. 33-42, 26/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEMAR, IRD, IFREMER, UBO EPE, CNRS