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Assia Kaci Fabienne Petit Patrick Lesueur Dominique Boust Anne Vrel Thierry Berthe 《Environmental science and pollution research international》2014,21(18):10787-10802
In estuarine ecosystems, trace metals are mainly associated with fine grain sediments which settle on mudflats. Over time, the layers of sediments accumulate and are then transformed by diagenetic processes, recording the history of the estuary’s chemical contamination. In such a specific environment, we investigated to what extent a chronic exposure to contaminants could affect metal-resistant sedimentary bacteria in subsurface sediments. The occurrence and diversity of cadmium resistance genes (cadA, czcA) was investigated in 5- and 33-year-old sediments from a highly contaminated estuary (Seine France). Primers were designed to detect a 252-bp fragment of the czcA gene, specifically targeting a transmembrane helice domain (TMH IV) involved in the proton substrate antiport of this efflux pump. Although the cadA gene was not detected, the highest diversity of the sequence of the czcA gene was observed in the 5-year-old sediment. According to the percentage of identity at the amino acid level, the closest CzcA relatives were identified among Proteobacteria (α, β, γ, and δ), Verrucomicrobia, Nitrospirae, and Bacteroidetes. The most abundant sequences were affiliated with Stenotrophomonas. In contrast, in the 33-year-old sediment, CzcA sequences were mainly related to Rhodanobacter thiooxydans and Stenotrophomonas, suggesting a shaping of the metal-resistant microbial communities over time by both diagenetic processes and trace metal contamination. 相似文献
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Naresh Kumar Romain Millot Fabienne Battaglia-Brunet Philippe Négrel Ludo Diels Jérôme Rose Leen Bastiaens 《Chemosphere》2013,90(4):1366-1371
In the present study, controlled laboratory column experiments were conducted to understand the biogeochemical changes during the microbial sulfate reduction. Sulfur and oxygen isotopes of sulfate were followed during sulfate reduction in zero valent iron incubated flow through columns at a constant temperature of 20 ± 1 °C for 90 d. Sulfur isotope signatures show considerable variation during biological sulfate reduction in our columns in comparison to abiotic columns where no changes were observed. The magnitude of the enrichment in δ34S values ranged from 9.4‰ to 10.3‰ compared to initial value of 2.3‰, having total fractionation δS between biotic and abiotic columns as much as 6.1‰. Sulfur isotope fractionation was directly proportional to the sulfate reduction rates in the columns. Oxygen isotopes in this experiment seem less sensitive to microbial activities and more likely to be influenced by isotopic exchange with ambient water. A linear relationship is observed between δ34S and δ18O in biotic conditions and we also highlight a good relationship between δ34S and sulfate reduction rate in biotic columns. 相似文献
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Yannick Mamindy-Pajany Charlotte Hurel Florence Géret François Galgani Fabienne Battaglia-Brunet Nicolas Marmier Michèle Roméo 《Chemosphere》2013,90(11):2730-2736
This work investigates arsenic mobility, bioavailability and toxicity in marine port sediments using chemical sequential extraction and laboratory toxicity tests. Sediment samples were collected from two different Mediterranean ports, one highly polluted with arsenic and other inorganic and organic pollutants (Estaque port (EST)), and the other one, less polluted, with a low arsenic content (Saint Mandrier port (SM)). Arsenic distribution in the solid phase was studied using a sequential extraction procedure specifically developed for appraising arsenic mobility in sediments. Toxicity assessment was performed on sediment elutriates, solid phases and aqueous arsenic species as single substance using the embryo-toxicity test on oyster larvae (Crassostrea gigas) and the Microtox test with Vibrio fischeri. Toxicity results showed that all sediment samples presented acute and sub-chronic toxic effects on oyster larvae and bacteria, respectively. The Microtox solid phase test allow to discriminate As-contaminated samples from the less contaminated ones, suggesting that toxicity of whole sediment samples is related to arsenic content. Toxicity of dissolved arsenic species as single substance showed that Vibrio fischeri and oyster larvae are most sensitive to As(V) than As(III). The distribution coefficient (Kd) of arsenic in sediment samples was estimated using results obtained in chemical sequential extractions. The Kd value is greater in SM (450 L kg?1) than in EST (55 L kg?1), indicating that arsenic availability is higher for the most toxic sediment sample (Estaque port). This study demonstrates that arsenic speciation play an important role on arsenic mobility and its bioavailability in marine port sediments. 相似文献
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Result-oriented approaches to the management of drinking water catchments in agricultural landscapes
Alexander Wezel Maria Zipfer Christine Aubry Fabienne Barataud Alois Heißenhuber 《Journal of Environmental Planning and Management》2016,59(2):183-202
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier. 相似文献
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By using a dynamic dilution system, the atmospheric measurement of 11 selected toxics VOCs (ethylene, acetylene, propene, 1-butene, 1,3-butadiene, 1-pentene, 1-hexene, benzene, toluene, ethylbenzene, m+p-xylene) from the list WHO of 1996 and TO-14 method of US EPA by preconcentration by thermal desorption (TD), analysis by gas chromatography (GC), identification and quantification with a flame ionisation detector (FID) was developed and validated in term of metrology, especially the techniques of sampling of these VOCs with adsorbents cartridges "Air Toxics" when used with an "UMEG sampler" equipped in the inlet with a nafion membrane. In particular the influence of climatic conditions (temperature and relative humidity) and the influence of chemical factors like ozone, on the representativity of sampling were studied. Experiments made with various humidities showed that the addition of a nafion membrane in the inlet of the sampling system was required. Without this membrane, losses of compounds were observed for RH >50%. With this membrane, storage for 2 weeks in a refrigerator, as for canisters, did not induce a loss of compounds. No significative decrease of concentrations of the studied VOCs after 14 days storage, which are known to react with ozone, were observed with an ozone concentrations of 55 ppb. One explanation is that nafion membrane, placed in the inlet of the sampler, will neutralize ozone before entering the sampling tubes. This observation is in accordance with literature which states that the sampling of VOCs on Carbotrap cartridges without ozone scrubber induce a loss of compounds. 相似文献
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A dynamic dilution system was used for the study of the influence of ozone on the sampling and storage of volatile organic
compounds (VOCs) at 0, 4, 7 and 14 days in “TO-Can” canisters at two ozone concentrations, 60 and 150 ppbv. Among the 31 ozone
precursors VOCs, a representative mixture containing five alkenes, five aromatics, acetylene and 1,3 butadiene was selected
using the Clausius–Clapeyron equation. Here, we demonstrate that the presence of ozone have no influence on the concentrations
of VOCs after 14 days storage period and consequently no problem of representativity of the sampling appears after 14 days
of storage. The main explanation is the degradation of ozone in contact with deactivated walls of canisters. 相似文献
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Mathilde Lefebvre Fabienne Dufernez Ange-Line Bruel Marie Gonzales Bernard Aral Judith Saint-Onge Nadège Gigot Julie Desir Caroline Daelemans Frédérique Jossic Sébastien Schmitt Raphaele Mangione Fanny Pelluard Catherine Vincent-Delorme Jean-Marc Labaune Nicole Bigi Dominique D'Olne Anne-Lise Delezoide Annick Toutain Sophie Blesson Valérie Cormier-Daire Julien Thevenon Salima El Chehadeh Alice Masurel-Paulet Nicole Joyé Claude Vibert-Guigue Luc Rigonnot Thierry Rousseau Pierre Vabres Philippe Hervé Antonin Lamazière Jean-Baptiste Rivière Laurence Faivre Nicole Laurent Christel Thauvin-Robinet 《黑龙江环境通报》2015,35(7):675-684
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Brigitte Simon-Bouy Agnès Taillandier Delphine Fauvert Isabelle Brun-Heath Jean-Louis Serre Carmen G. Armengod Martin G. Bialer Michèle Mathieu Jacques Cousin David Chitayat Jan Liebelt Barbara Feldman Marion Gérard-Blanluet Stefani Körtge-Jung Cath King Hannele Laivuori Martine Le Merrer Sarju Mehta Christina Jern Saba Sharif Fabienne Prieur Gabriele Gillessen-Kaesbach Andreas Zankl Etienne Mornet 《黑龙江环境通报》2008,28(11):993-998