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Registros recuperados: 42 | |
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Thibault De Chanvalon, A.; Mouret, A.; Knoery, Joel; Geslin, E.; Peron, O.; Metzger, E.. |
The sampling of surface sediment from two sites of a mudflat of the Loire Estuary during four contrasting seasons has led to new information about geochemical cycling under transient diagenesis fuelled by flood deposition. Based on stocks of reactive iron-oxides and manganese-oxides (ascorbate-extracted) and pore water concentrations, the progressive evolution of flood deposits is described. Three major steps are observed: at first, there is no manganese, iron and phosphorus release into pore water within the flood-deposited layer. Then, during a period of approximately 1 month, Mn oxides are consumed while the dissolved Mn concentration increases. Simultaneously, the Fe oxide-rich layer from flood deposition prevents (or at least limits) phosphorus... |
Tipo: Text |
Palavras-chave: Flood deposition; Ascorbat extraction; Transient diagenesis; Savitzky Golay filter; RiOMars. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00354/46525/46291.pdf |
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Knoery, Joel; Cossa, Daniel; Thomas, Bastien; Germain, Gregory; Rigaud, Sylvain. |
In aquatic environments, the benthic water column exhibits strong concentration gradients of various substances. They result from transfers and chemical reactions that may occur both within this layer, and at the sediment–water interface (SWI). Characterization of these gradients yields important information for the quantification of such processes and transfers. However, it is difficult to actually sample these gradients in the field, since turbulence decreases their vertical scale. This article describes a sampler designed to collect simultaneously 16 discrete water column samples at a centimeter‐scale vertical resolution. This small device (40 × 40 × 60 cm) is reliable, safe to handle, and easily deployed from a small boat using a cable or a Scuba... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00495/60665/64203.pdf |
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Chouvelon, Tiphaine; Cresson, Pierre; Bouchoucha, Marc; Brach-papa, Christophe; Bustamante, Paco; Crochet, Sylvette; Marco-miralles, Francoise; Thomas, Bastien; Knoery, Joel. |
Mercury (Hg) is a global contaminant of environmental concern. Numerous factors influencing its bioaccumulation in marine organisms have already been described at both individual and species levels (e.g., size or age, habitat, trophic level). However, few studies have compared the trophic characteristics of ecosystems to explain underlying mechanisms of differences in Hg bioaccumulation and biomagnification among food webs and systems. The present study aimed at investigating the potential primary role of the trophic status of systems on Hg bioaccumulation and biomagnification in temperate marine food webs, as shown by their medium-to high-trophic level consumers. It used data from samples collected at the shelf-edge (i.e. offshore organisms) in two... |
Tipo: Text |
Palavras-chave: Biomagnifying metal; Bioaccumulation; Trophic status; Ecosystem productivity; Temperate systems. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00410/52111/52936.pdf |
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Gil-díaz, Teba; Schäfer, Jörg; Dutruch, Lionel; Bossy, Cécile; Pougnet, Frédérique; Abdou, Melina; Lerat-hardy, Antoine; Pereto, Clément; Derriennic, Hervé; Briant, Nicolas; Sireau, Teddy; Knoery, Joel; Blanc, Gerard. |
Tellurium (Te) is a technology critical element (TCE) with largely unknown environmental behaviour, especially in continent-ocean interface systems. The unknown behaviour results from the lack of studies in aquatic environments and from analytical challenges limiting the determination of its naturally low (ultra-trace) environmental levels. We performed a comprehensive study of Te in the Lot–Garonne–Gironde fluvial–estuarine system to better understand seasonal variations, solid/liquid partitioning (Kd), gross fluxes, estuarine dynamics, and transfer to wild oysters at the estuary mouth. A temporal record (2014–2017) of dissolved (Ted) and particulate (Tep) Te concentrations at five sites in the Lot–Garonne River system shows little differences between... |
Tipo: Text |
Palavras-chave: Garonne River; Gironde Estuary; Lot River; RNO; ROCCH; Technology critical element. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00505/61684/65639.pdf |
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Briant, Nicolas; Chouvelon, Tiphaine; Martinez, Laura; Brach-papa, Christophe; Chiffoleau, Jean-francois; Savoye, N.; Sonke, J.; Knoery, Joel. |
Marine mercury (Hg) concentrations have been monitored in the French coastline for the last half a century using bivalves. The analyses presented in this study concerned 192 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from 77 sampling stations along the French coast and in the French Antilles sea. The goals of this study were to assess MeHg levels in various common bivalves from French coastline, and to identify possible geographic, taxonomic or temporal variations of concentrations. We show that the evolution of methylmercury (MeHg) concentrations covary with total mercury (HgT) concentrations. Moreover, in most of the study sites, HgT concentrations have not decreased... |
Tipo: Text |
Palavras-chave: Mercury; Methylmercury; France; Bivalves; Speciation. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00353/46465/46398.pdf |
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Nikolic, Natacha; Puech, Alexis; Chouvelon, Tiphaine; Munschy, Catherine; Bodin, Nathalie; Brach-papa, Christophe; Potier, Michel; West, Wendy; Knoery, Joel; Zudaire, Iker; Dhurmeea, Zahirah; Degroote, Maxime; Cedras, Maria; Evano, Hugues; Bourjea, Jerome. |
The GERMON project had several aims i) to understand the populations’ structure between albacore tuna southwest of the Indian Ocean and southeast Atlantic, ii) to determine the origin of juveniles observed in South Africa iii) to improve the understanding of the biology field (Size/Size and Size/Weight; reproduction and feeding area; trophic linkages) and iv) to initiate work on chemical analyzes and adaptation of the albacore species to its environment. These aims have been held and the results allow a better understanding of the management albacore. A general summary of results is presented in Part 9. |
Tipo: Text |
Palavras-chave: Germon; Thunnus alalunga; Génétique; Stock; Structure; Connectivité; Chimie; Reproduction; Alimentation; Habitat; Albacore; Thunnus alalunga; Genetic; Stock; Structure; Connectivity; Chemical; Reproduction; Feeding behavior; Habitat. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00293/40461/39152.pdf |
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German, C. R.; Thurnherr, A. M.; Knoery, Joel; Charlou, Jean-luc; Jean-baptiste, P.; Edmonds, H. N.. |
High-temperature hydrothermal activity occurs in all ocean basins and along ridge crests of all spreading rates. While it has long been recognized that the fluxes associated with such venting are large, precise quantification of their impact on ocean biogeochemistry has proved elusive Here, we report a comprehensive study of heat, fluid and chemical fluxes from a single submarine hydrothermal field. To achieve this, we have exploited the integrating nature of the non-buoyant plume dispersing above the Rainbow hydrothermal field, a long-lived and tectonically hosted high-temperature vent site on the Mid-Atlantic Ridge. Our calculations yield heat and volume fluxes for high-temperature fluids exiting the seafloor of similar to 0.5 GW and 450 Ls(-1), together... |
Tipo: Text |
Palavras-chave: Hydrothermal fluxes; Biogeochemistry; Rainbow vent-field. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11423/8040.pdf |
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Briant, Nicolas; Chouvelon, Tiphaine; Brach-papa, Christophe; Chiffoleau, Jean-francois; Savoye, Nicolas; Sonke, Jeroen; Knoery, Joel. |
Mercury (Hg) is a natural element toxic to all living organisms. Its ocean biogeochemical cycle is dominated by atmospheric deposition, which human activities contribute to disrupt signi cantly, and to a lesser extent by riverine discharge. This element is bioamplifed and bioaccumulated in marine food webs. since mercury concentrations in some coastal animal species of high trophic level approach sanitary thresholds, understanding biogeochemical processes and mechanisms leading to these elevated Hg concentrations becomes important. The stable isotopic geochemistry of metal is indeed a very promising way to trace processes and transfers from one mercury biogeochemical reservoir to another (Sonke and Blum, 2013). The stable isotopes of Hg undergo... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00394/50561/51253.pdf |
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De Chanvalon, A. Thibault; Metzger, E.; Mouret, A.; Cesbron, F.; Knoery, Joel; Rozuel, Emmanuelle; Launeau, P.; Nardelli, M. P.; Jorissen, F. J.; Geslin, E.. |
We present a new rapid and accurate protocol to simultaneously sample benthic living foraminifera in two dimensions in a centimeter scale vertical grid and dissolved iron in high resolution (200 μm). Such an approach appears crucial to study foraminiferal ecology in heterogeneous environments. The foraminiferal faunas of the main intertidal mudflat of the Loire estuary are dominated by Ammonia tepida, which accounts for 92 % of the living assemblage (CTG-labeled). Its vertical distribution shows a first density maximum at the surface, a sharp decrease in the next two centimeter followed by a well defined second maximum between 3 and 8 cm depth. The heterogeneity of A. tepida in this 3–8 cm depth layer was calculated by the Moran's Index and reveals lateral... |
Tipo: Text |
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Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00277/38786/37335.pdf |
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Auzende, Jean-marie; Ishibashi, J; Beaudouin, Y; Charlou, Jean-luc; Delteil, J; Donval, Jean-pierre; Fouquet, Yves; Gouillou, Jp; Ildefonse, B; Kimura, H; Nishio, Y; Knoery, Joel; Ruollan, E. |
In 1995, a joint French‐Japanese cruise (ManusFlux) explored the Manus Spreading Center and some sites of the South Eastern Rift in the Manus Basin off the coast of Papua New Guinea (Figure 1) with the Japanese submersible [Auzende et al., 1996; Gamo et al., 1997]. In the framework of this joint project, called New STARMER, the French and Japanese teams completed the Manaute cruise with the R/V LAtalante and the Ifremer submersible Nautile in April and May 2000. The Manaute cruise explored and sampled volcanic and hydrothermal sites in the eastern part of Manus Basin and on the spreading axis of the Western Ridge (WR). The eastern part of the Manus Basin (Figure 2) was interpreted as a stretched‐back arc basin crust showing alternatively elongated ridges... |
Tipo: Text |
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Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00069/18055/15597.pdf |
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Thibault De Chanvalon, A.; Metzger, E.; Mouret, A.; Knoery, Joel; Geslin, E.; Meysman, F. J. R.. |
Coastal and shelf sediments are considered as an important source of dissolved iron to the ocean. Here, we present a new numerical approach to estimate geochemical fluxes and production rates in an estuarine sediment at sub-millimetre resolution. This approach is based on application of Savitsky–Golay filter (SGF) procedure to two-dimensional concentration distributions of dissolved iron. We verified the procedure by applying it to artificial data of known production rates, and analysed the resulting uncertainty on production rates and fluxes across the water–sediment interface. This SGF procedure was applied to data from an intertidal mudflat that is densely inhabited by macrofauna (e.g. 630 ind m− 2 of Hediste diversicolor, I. Métais, pers.com.). Our... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00332/44365/43970.pdf |
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Cresson, Pierre; Fabri, Marie-claire; Bouchoucha, Marc; Brach-papa, Christophe; Chavanon, Fabienne; Jadaud, Angelique; Knoery, Joel; Marco-miralles, Francoise; Cossa, D.. |
Mercury (Hg) is a global threat for marine ecosystems, especially within the Mediterranean Sea. The concern is higher for deep-sea organisms, as the Hg concentration in their tissues is commonly high. To assess the influence of food supply at two trophic levels, total Hg concentrations and carbon and nitrogen stable isotope ratios were determined in 7 species (4 teleosts, 2 sharks, and 1 crustacean) sampled on the upper part of the continental slope of the Gulf of Lions (Northwestern Mediterranean Sea), at depths between 284 and 816 m. Mean Hg concentrations ranged from 1.30 ± 0.61 to 7.13 ± 7.09 μg g− 1 dry mass, with maximum values observed for small-spotted catshark Scyliorhinus canicula. For all species except blue whiting Micromesistius poutassou, Hg... |
Tipo: Text |
Palavras-chave: Continental slope; Trophic webs; Depth; Teleosts; Sharks; Stable isotopes. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00206/31759/30693.pdf |
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Mattio, Elodie; Ollivier, Nadia; Robert-peillard, Fabien; Di Rocco, Robert; Branger, Catherine; Margaillan, Andre; Brach-papa, Christophe; Knoery, Joel; Bonne, Damien; Boudenne, Jean-luc; Coulomb, Bruno. |
3D printing technology is increasingly used in flow analysis, to develop low cost and tailor-made devices. The possibility of grafting specific molecules onto 3D printed parts offers new perspectives for the development of flow systems. In this study, a MPFS system including a dicarboxylate 1,5-diphenyl-3-thiocarbazone grafted 3D-printed device has been developed for mercury determination. For this purpose, the surface of 3D-printed cuboids was first modified with amine functional groups and then grafted with dicarboxylate 1,5-diphenyl-3-thiocarbazone. This new grafted device resulted in selective mercury preconcentration with extraction and elution yields higher than 90% even at high sampling flow rates. The detection can then be carried out in two ways:... |
Tipo: Text |
Palavras-chave: Stereolithography Poly(methylmethacrylate) grafting Dicarboxylate 1; 5-diphenyl-3-thiocarbazone Multi pumping flow system Mercury. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00505/61682/65631.pdf |
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Ferreira Araujo, Daniel; Ponzevera, Emmanuel; Briant, Nicolas; Knoery, Joel; Bruzac, Sandrine; Sireau, Teddy; Brach-papa, Christophe. |
Toulon bay is severely impacted by metal contamination induced by past and recent naval activities. In this work, Cu, Zn and Pb isotope compositions and elemental concentrations of fifty-five surface sediments were determined in order to map the spatial distribution of anthropogenic and natural sources along this land-sea continuum. Two sub-systems of Toulon Bay, the Small and Large bays, showed well-marked patterns on metal contamination levels and isotope signatures for Cu and Pb. The Small bay had the highest metal concentrations, and displayed average Pb and Cu isotope compositions of 1.1664 ± 0.0043 (1s, expressed as 206Pb/207Pb ratios) and −0.17 ± 0.19‰ (1s, expressed as δ65CuNIST values), respectively. It contrasted with the Large bay, with moderate... |
Tipo: Text |
Palavras-chave: Metal isotopes; Isotope tracers; Geochemical isotopes; Environmental pollution; Coastal pollution; Toulon bay. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00566/67784/67226.pdf |
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Brach-papa, Christophe; Chiffoleau, Jean-francois; Knoery, Joel; Chouvelon, Tiphaine; Auger, Dominique; Bretaudeau-sanjuan, Jane; Crochet, Sylvette; Rozuel, Emmanuelle; Thomas, Bastien; Vasileva, Emilia; Oriana, Anna Maria. |
The Loire River is one of the largest river systems in Western Europe and a major source of continental inputs to the marine environment in the Bay of Biscay. Its catchment area drains agricultural and industrial zones and its estuary is increasingly urbanized. Even if the Loire River is not considered as a highly polluted system, studies have shown estuarine Pb contamination due to industrial inputs and combustion of leaded gasoline until the mid 1990’s. A retrospective study, based on the analysis (Pb levels and isotopic composition) of mussel samples collected by the French mussel watch program (RNO/ROCCH) has highlighted this contamination and its trend between 1985-2005 (Couture et al., 2010). This poster furthers the work initiated by Couture et al.... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29958/28404.pdf |
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Marusczak, Nicolas; Castelle, Sabine; De Voguee, Benoist; Knoery, Joel; Cossa, Daniel. |
The seasonal variation and spatial distribution of atmospheric particles at three islands in the Taiwan Strait were investigated. Atmospheric particles (PM10) were collected at three offshore islands (i.e., Kinmen islands, Matsu islands, and Penghu Islands) and two coastal regions (i.e., Xiamen and Fuzhou) in the years of 2008–2012. Field sampling results indicated that the average PM10 concentrations at the Kinmen islands were generally higher than other sampling sites, suggesting that a superimposition phenomenon was regularly observed during the air pollution episodes at Kinmen Islands and Xiamen region. PM10 samples were analyzed for their chemical composition, including water-soluble ions, metallic elements, and carbonaceous content. The most abundant... |
Tipo: Text |
Palavras-chave: Total gaseous mercury; Coastal Mediterranean site; Anthropogenic and local sources; Seasonal and daily variations. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00276/38769/37540.pdf |
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Briant, Nicolas; Knoery, Joel; Chouvelon, Tiphaine; Brach-papa, Christophe; Chiffoleau, Jean-francois; Savoye, Nicolas; Sonke, Jeroen. |
Mercury cycles between atmosphere, terrestrial and aquatic reservoirs through a complex combination of transport and transformation processes, until it is buried in oceanic or terrestrial sediments. Monomethylmercury is the main species bioaccumulated and bioampli ed in the food chain. Knowledge of the origin (continental, oceanicorlocalsediment)ofthisspeciesforthelittoralenvironnment can still be improved. This study focuses on ~200 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from ~80 stations along the French coast. The goals of this study were i) to describe Hg levels, speciation and isotopic composition in various bioindicator bivalves from the French coastline, and ii)... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00394/50562/51254.pdf |
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Grouhel-pellouin, Anne; Knoery, Joel; Marchand, Philippe. |
Le ROCCH produit les données chimiques nécessaires à l’évaluation de la qualité chimique des eaux marines, et notamment la qualité sanitaire des zones conchylicoles françaises. En 2018, 76 échantillons de mollusques ont été collectés et analysés dans ce cadre, complétés de 46 points hors suivi sanitaire. Trois secteurs apparaissent préoccupants en février 2018: le sud de la rade de Brest (fortes teneurs en plomb dans les moules et teneurs élevées en cadmium dans les huîtres), la baie de Marseille ((fortes teneurs en plomb dans les moules et teneurs élevées en HAP) et l’estuaire de la Gironde (fortes teneur en cadmium dans les huîtres), la baie de Toulon (teneurs élevées en plomb des moules), le pertuis charentais (teneurs élevées en cadmium des huîtres),... |
Tipo: Text |
Palavras-chave: Chimie; Qualité sanitaire; Mollusques; ROCCH; France. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00507/61820/65829.pdf |
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Chouvelon, Tiphaine; Brach-papa, Christophe; Auger, Dominique; Bodin, Nathalie; Bruzac, Sandrine; Crochet, Sylvette; Degroote, Maxime; Hollanda, Stephanie J.; Hubert, Clarisse; Knoery, Joel; Munschy, Catherine; Puech, Alexis; Rozuel, Emmanuelle; Thomas, Bastien; West, Wendy; Bourjea, Jerome; Nikolic, Natacha. |
Albacore tuna (Thunnus alalunga) is a highly commercial fish species harvested in the world's Oceans. Identifying the potential links between populations is one of the key tools that can improve the current management across fisheries areas. In addition to characterising populations' contamination state, chemical compounds can help refine foraging areas, individual flows and populations' structure, especially when combined with other intrinsic biogeochemical (trophic) markers such as carbon and nitrogen stable isotopes. This study investigated the bioaccumulation of seven selected trace metals – chromium, nickel, copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg) and lead – in the muscle of 443 albacore tunas, collected over two seasons and/or years in the... |
Tipo: Text |
Palavras-chave: Top predator; Bioaccumulation; Inorganic elements; Organic contaminants; Stable isotopes; Intrinsic markers. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00384/49532/51152.pdf |
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Registros recuperados: 42 | |
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