Consulta: creatorFacets:"Coynel, Alexandra"
Registros recuperados: 5
Data/hora: 20/05/2024 05:31:21

Flux estimation, temporal trends and source determination of trace metal contamination in a major tributary of the Seine estuary, France
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Gardes, Thomas; Debret, Maxime; Copard, Yoann; Coynel, Alexandra; Deloffre, Julien; Fournier, Matthieu; Revillon, Sidonie; Nizou, Jean; Develle, Anne-lise; Sabatier, Pierre; Marcotte, Stéphane; Patault, Edouard; Faivre, Quentin; Portet-koltalo, Florence.
Anthropogenic impacts on rivers have increased significantly over the past ~150 years, particularly at the beginning of the industrial revolution. Among other signs, this impact is manifested through the addition of trace metals and metalloid elements to rivers. The Eure River watershed in France covers an area of 6017 km2 and is a major tributary of the Seine estuary. It is not exempt from anthropogenic pressures and has been exposed to significant metal discharges over the last 80 years. The average concentrations of metals (i.e., Cr, Co, Ni, Cu, Zn, Ag, Cd, Sb, and Pb), in suspended particulate matter currently transported by the river are high compared to the local geochemical background. Moreover, the lack of correlation between concentration...
Tipo: Text
Palavras-chave: Anthropogenic impacts; Trace metals and metalloids; Eure River watershed; Temporal trends; Particulate metal flux; Pb isotopes.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00618/73046/72159.pdf

L'argent (Ag, nanoAg) comme contaminant émergeant dans l'Estuaire de la Gironde : évaluations scientifiques et gouvernance des risques
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Salles, Denis; Roumezi, Alexis; Lanceleur, Laurent; Schaefer, Jorg; Petit, Jerome; Blanc, Gerard; Coynel, Alexandra; Chiffoleau, Jean-francois; Auger, Dominique.
This article presents the results of multidisciplinary research (geochemistry, sociology) into the increasing concentrations of silver (Ag and nanoAg) in the environment and their potential impact on aquatic environments. We investigate simultaneously the risk of contamination of these environments by silver and the process of the social and political construction of this risk by water managers, health authorities, agencies and committees responsible for expert evaluations, environmental associations, and potential users of silver or nano-silver. Four updated models of risk construction allow us to understand the logic of arguments mobilized at this stage of the emerging risk. This interdisciplinary cooperation opens up possibilities for dealing with some...
Tipo: Text
Palavras-chave: Environment; Estuaries; Geochemistry; Interdisciplinary communication; Nanotechnology; Risk assessment; Risk management; Silver; Sociology; Water pollutants.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00156/26736/24939.pdf

Nutrient export to an Eastern Atlantic coastal zone: first modeling and nitrogen mass balance
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Canton, Mathieu; Anschutz, Pierre; Coynel, Alexandra; Polsenaere, Pierre; Auby, Isabelle; Poirier, Dominique.
We have studied 15 catchments supplying freshwater to a French Atlantic coastal lagoon, where increase in nitrogen loads due to agriculture is supposed to have destabilized the ecosystem in the last decades. The catchment is a lowland composed of Pleistocene sands with an average slope of 0.25%. To study the nutrient export in relation to land-use surface waters were sampled bi-weekly between October 2006 and January 2009 and land-use was established by plane photographs and Geographic Information System (GIS). Cultivated pine forests represent more than 80% of the total surface and 7% of the catchment area has been deforested recently. Significant areas of some catchments are used for maize crop. Housing is confined to the coastal zone. Maize and forest...
Tipo: Text
Palavras-chave: Nitrogen; Phosphorus; River export; Land use; Coastal catchment; Arcachon Bay; Modeling; Mass balance.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00065/17615/15173.pdf

Spatial and temporal variations in trace metal concentrations in surface sediments of the Marennes Oleron Bay. Relation to hydrodynamic forcing
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Strady, Emilie; Kervella, Stephane; Blanc, Gerard; Robert, Serge; Stanisiere, Jean-yves; Coynel, Alexandra; Schaefer, Joerg.
Sediments quality assessment is of priority concern to provide a comprehensible overview of ecological and chemical state of an ecosystem. The Marennes-Oleron Bay, hosting the largest oyster production in France, is influenced by the historic polymetallic pollution of the Gironde Estuary. Despite, management efforts and decreasing emissions in the Gironde watershed, Cd levels in oysters from the bay are close to consumption limit (5 pig g(-1) dw. EC no. 466/2001). In this context, the aim of the study was to assess the priority metal (Ni, Cu, Zn, As, Ag, Cd, Hg, Pb and Th) concentrations in sediment within the Bay, by investigating spatial and temporal distribution variations and the role of hydrodynamic forcing. For that we selected three sites (east,...
Tipo: Text
Palavras-chave: Trace metal; Marennes Oleron Bay; Enrichment factor; Sediment; Hydrodynamic; Altus.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00038/14914/15996.pdf

The estuarine geochemical reactivity of Zn isotopes and its relevance for the biomonitoring of anthropogenic Zn and Cd contaminations from metallurgical activities: Example of the Gironde fluvial-estuarine system, France
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Petit, Jerome C. J.; Schafer, Jörg; Coynel, Alexandra; Blanc, Gerard; Chiffoleau, Jean-francois; Auger, Dominique; Bossy, Cecile; Derriennic, Herve; Mikolaczyk, Mathilde; Dutruch, Lionel; Mattielli, Nadine.
Zinc stable isotopes measurements by MC-ICP-MS, validated by laboratory intercalibrations, were performed on wild oysters, suspended particles and filtered river/estuarine water samples to provide new constraints for the use of Zn isotopes as environmental tracers. The samples selected were representative of the long range (400 km) transport of metal (Zn, Cd, etc.) contamination from former Zn-refining activities at Decazeville (i.e. δ66Zn &gt; 1 ‰) and its phasing out, recorded during 30 years in wild oysters from the Gironde Estuary mouth (RNO/ROCCH sample bank). The study also addresses additional anthropogenic sources (urban and viticulture) and focuses on geochemical reactivity of Zn in the turbidity gradient and the maximum turbidity zone (MTZ) of...
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00277/38852/37390.pdf