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| Cossa, Daniel; Heimbuerger, Lars-eric; Lannuzel, Delphine; Rintoul, Stephen R.; Butler, Edward C. V.; Bowie, Andrew R.; Averty, Bernard; Watson, Roslyn J.; Remenyi, Tomas. |
| We present here the first mercury speciation study in the water column of the Southern Ocean, using a high-resolution south-to-north section (27 stations from 65.50 degrees S to 44.00 degrees S) with up to 15 depths (0-4440 m) between Antarctica and Tasmania (Australia) along the 140 degrees E meridian. In addition, in order to explore the role of sea ice in Hg cycling, a study of mercury speciation in the "snow-sea ice-seawater" continuum was conducted at a coastal site, near the Australian Casey station (66.40 degrees S; 101.14 degrees E). In the open ocean waters, total Hg (Hg(T)) concentrations varied from 0.63 to 2.76 pmol L(-1) with "transient-type" vertical profiles and a latitudinal distribution suggesting an atmospheric mercury source south of the... |
| Tipo: Text |
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| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00041/15221/12677.pdf |
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| Heimbuerger, Lars-eric; Cossa, Daniel; Marty, Jean-claude; Migon, Christophe; Averty, Bernard; Dufour, Aurelie; Ras, Josephine. |
| Recent findings on the distribution of methylated mercury (MeHgT) in waters have highlighted the importance of organic carbon remineralization on the production of these compounds in the open ocean. Here, we present the first time-series (20 monthly samplings between July 2007 and May 2009) of high-resolution vertical profiles (10-12 depths in a 2350 m water column) of MeHgT distributions in an open ocean environment, the Ligurian Sea (North-western Mediterranean Sea). Concentrations varied within the sub-picomolar range (general mean: 0.30 0.17 pmol L-1, n = 214) with the lowest values at the surface, increasing with depth up to the oxygen minimum zone, and decreasing slowly at greater depth. Concentrations in the surface waters never exceeded 0.15 pmol... |
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| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00013/12415/9225.pdf |
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| Heimbuerger, Lars-eric; Cossa, Daniel; Thibodeau, Benoit; Khripounoff, Alexis; Mas, Virginie; Chiffoleau, Jean-francois; Schmidt, Sabine; Migon, Christophe. |
| The magnitude and the chronology of anthropogenic impregnation by Hg and other trace metals of environmental concern (V, Cr, Ni, Cu, Zn, Ag, Cd and Pb, including its stable isotopes) in the sediments are determined at the DYFAMED station, a site in the Ligurian Sea (Northwestern Mediterranean) chosen for its supposed open-sea characteristics. The DYFAMED site (VD) is located on the right levee of the Var Canyon turbidite system, at the end of the Middle Valley. In order to trace the influence of the gravity current coming from the canyon on trace metal distribution in the sediment, we studied an additional sediment core (VA) from a terrace of the Var Canyon, and material collected in sediment traps at the both sites at 20 m above sea bottom. The patterns... |
| Tipo: Text |
Palavras-chave: Marine sediments; Sediment traps; Mercury; Trace metals; Lead isotopes; Geochronology. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00073/18435/16125.pdf |
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| Heimbuerger, Lars-eric; Migon, Christophe; Dufour, Aurelie; Chiffoleau, Jean-francois; Cossa, Daniel. |
| Climatic and anthropogenic changes are able to engender modifications in the aerosol composition at different geographical and temporal scales The present study addresses this question for the trace metal concentrations (TM = Al, Fe, Mn, Co, Ni, Cu, Pb, Cd and Zn) of aerosol from the North-western Mediterranean coast of France (Cap Ferrat, nearby Nice) between 1986 and 2008. From seasonal variations (2006-08) and decadal trends (1986-2008) of TM concentrations. three groups of elements can be distinguished They consist of different aerosol sources: crustal-derived elements (Al, Fe. Mn and Co), trace metals of anthropogenic origin (Pb, Cd and Zn) and a third, intermediate, group of trace metals that presented both anthropogenic and natural/crustal... |
| Tipo: Text |
Palavras-chave: Trace metals; Aerosols; Anthropic impact; Mediterranean; Anti-pollution policy. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11688/8503.pdf |
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| Heimbuerger, Lars-eric; Migon, Christophe; Losno, Rémi; Miquel, Juan-carlos; Thibodeau, Benoit; Stabholz, Marion; Dufour, Aurelie; Leblond, Nathalie. |
| We examined metal (Al, V, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb) and particulate organic carbon (OC) concentrations of the marine vertical export flux at the DYFAMED time-series station in the Northwestern Mediterranean Sea. We present here the first data set of natural and anthropogenic metals from sediment trap moorings deployed at 1000 m-depth between 2003 and 2007 at the DYFAMED site. A highly significant correlation was observed between most metal concentrations, whatever the nature and emission source of the metal. Cu, Zn and Cd exhibit different behaviors, presumably due to their very high solubility and complexation with organic ligands. The observed difference of atmospheric and marine fluxes in terms of temporal variability and elemental... |
| Tipo: Text |
Palavras-chave: Trace metals; Sediment trap; Mediterranean Sea; Vertical export flux; Ballasting. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00176/28774/27247.pdf |
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