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Registros recuperados: 67 | |
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Marchand, Michel; Caprais, Jean-claude. |
The analysis of volatile organic substances requires a specifie methodology. We have taken up the Grob's procedure [1]. Enrichment of the volatile trace organics is performed by close-loop gaseous stripping followed by absorption on a microcharcoal filter. The organic substances are eluted from the charcoal by 15 µ of carbon disulfide and analyzed by high resolution gas chromatography. The recovery of the method (trapping from water, desorption from activated charcoal) is determined for different kinds of volatile organic compounds: saturated hydrocarbons (n-C7 to n-C19), aromatic hydrocarbons (benzene, naphtalene and alkylated compounds) and chloro-aromatic hydrocarbons of benzene and naphthalene. |
Tipo: Text |
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Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/00186/29769/28212.pdf |
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Sarradin, Pierre-marie; Caprais, Jean-claude. |
This preliminary study presents a new method for the determination of dissolved gases in sea-water. After headspace extraction, gaseous compounds are separated by GC on a dual column adsorption system, The individual species are thereafter eluted to three different detectors (thermal conductivity, flame ionization and FPD) using a second switching valve, The analysis is quantitative for methane and carbon dioxide with limits of determination of 0.1 and 50 mu mol l(-1), respectively, and corresponding standard deviations of 4 and 7%, and has been applied to deep sea hydrothermal samples, Further optimization is necessary to allow the quantitative determination of hydrogen sulfide, nitrogen, oxygen and carbon monoxide. |
Tipo: Text |
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Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00186/29766/28198.pdf |
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Vigneron, Adrien; Cruaud, Perrine; Pignet, Patricia; Caprais, Jean-claude; Gayet, Nicolas; Cambon-bonavita, Marie-anne; Godfroy, Anne; Toffin, Laurent. |
The Sonora Margin cold seeps present on the seafloor a patchiness pattern of white microbial mats surrounded by polychaete and gastropod beds. These surface assemblages are fuelled by abundant organic inputs sedimenting from the water column and upward-flowing seep fluids. Elevated microbial density was observed in the underlying sediments. A previous study on the same samples identified anaerobic oxidation of methane (AOM) as the potential dominant archaeal process in these Sonora Margin sediments, probably catalysed by three clades of archaeal anaerobic methanotrophs (ANME-1, ANME-2 and ANME-3) associated with bacterial syntrophs. In this study, molecular surveys and microscopic observations investigating the diversity of Bacteria involved in AOM... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00168/27921/27279.pdf |
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Decker, Carole; Zorn, N.; Le Bruchec, J.; Caprais, Jean-claude; Potier, N.; Leize-wagner, E.; Lallier, F. H.; Olu, Karine; Andersen, A. C.. |
Vesicomyids live in endosymbiosis with sulfur-oxidizing bacteria and therefore need hydrogen sulfide to survive. They can nevertheless live in a wide range of sulfide and oxygen levels and depths, which may explain the exceptional diversity of this clam family in deep-sea habitats. In the Gulf of Guinea, nine species of vesicomyid clams are known to live in cold-seep areas with pockmarks from 600 to 3200 m deep, as well as in the organic-rich sediments of the Congo deep-sea fan at 5000 m deep. Our previous study showed that two species living in a giant pockmark have different oxygen carriers, suggesting different adaptations to hypoxia. Here, we studied the hemoglobin structure and oxygen affinity in three other species, Calyptogena valdiviae, Elenaconcha... |
Tipo: Text |
Palavras-chave: Hemoglobin; Mass spectrometry; Oxygen affinity; Symbiont-bearing bivalve; Blood-clams; Cold seeps; Sulfide-rich sediments. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00358/46961/46875.pdf |
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Sarradin, Pierre-marie; Caprais, Jean-claude; Briand, Patrick; Gaill, Françoise; Shillito, Bruce; Desbruyeres, Daniel. |
The objective of this study is to describe the chemical and physical environment surrounding the vent organisms at the Genesis site (EPR, 2640 m). The main chimney is colonized by Riftia pachyptila, fishes Zoarcidae and crabs Bythograeidae. The top of the smoker is covered with tubes of polychaetes Alvinellidae, the frontier zone by limpet gastropods. Temperature measurements and water sampling were made on an axis along the chimney. The environment was characterized using relationships between chemical concentrations and temperature to provide a chemo-thermal model of the site. Discrete temperature ranges were 1-1.6 degrees C in sea water, 1.6-10 degrees C among Riftia plumes (up to 25 degrees C at the tube base), 7-91 degrees C close to the alvinellid... |
Tipo: Text |
Palavras-chave: Hydrothermal ecosystem; Hydrogen sulphide; Carbon dioxide; Temperature. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00186/29764/28200.pdf |
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Sarradin, Pierre-marie; Caprais, Jean-claude; Riso, Ricardo; Kerouel, Roger; Aminot, Alain. |
Water samples were collected around the communities of a hydrothermal mussel, Bathymodiolus sp., in the Lucky Strike (1700 m depth) and Menez Gwen (850 m depth) areas, Mid Atlantic Ridge, and analysed for chemical constituents. The environment surrounding the organisms consists in sea water (88 to 100%) mixed with hydrothermal fluid with pH between 6.2 and 8, Sigma S (H2S + HS-) concentrations from 0 to 62 mu mol l(-1). High dissolved organic carbon (DOC) concentrations suggest a highly productive ecosystem. Production of ammonium and DOG, consumption of nitrate and sulfide in the vicinity of the organisms are among the environmental changes found in relation with local biological activity. Concentrations of Cu and Pb were high, implying that the organisms... |
Tipo: Text |
Palavras-chave: Environment; Sea water; Hydrothermal vents; Mussels. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00147/25847/23968.pdf |
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Olu, Karine; Caprais, Jean-claude; Fifis, Alexis; Fabri, Marie-claire; Galeron, Joelle; Budzinsky, H; Le Menach, K; Khripounoff, Alexis; Ondreas, Helene; Sibuet, Myriam. |
A giant pockmark colonised by dense cold-seep assemblages near 3160 m depth along the Congo-Angola margin has been surveyed by the ROV Victor 6000. The quantitative distribution of chemosynthetic communities was mapped along the dive tracks from a video study using GIS and image mosaicking. Several types of faunal assemblages, either dominated by bivalves of the families Mytilidae (Bathmodiolus sp.) Vesicom idae (Calyptogena sp., 'Vesicomya' aff. chuni), or by Siboglinidae polychaetes (Escarpia southwardae) were mapped over the 800-m diameter pockmark area and sampled for fauna, water and sediment. The isotopic analyses (delta C-13) of tissues from symbiont-bearing species were within the range typical of nutrition via symbiosis using methane for mussels... |
Tipo: Text |
Palavras-chave: Symbiont bearing species; Spatial distribution; Methane; Megafauna; Cold seeps. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2681.pdf |
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Olu, Karine; Decker, Carole; Pastor, Lucie; Caprais, Jean-claude; Khripounoff, Alexis; Morineaux, Marie; Ain Baziz, M.; Menot, Lenaick; Rabouille, C.. |
Methane-rich fluids arising from organic matter diagenesis in deep sediment layers sustain chemosynthesis-based ecosystems along continental margins. This type of cold seep develops on pockmarks along the Congo margin, where fluids migrate from deep-buried paleo-channels of the Congo River, acting as reservoirs. Similar ecosystems based on shallow methane production occur in the terminal lobes of the present-day Congo deep-sea fan, which is supplied by huge quantities of primarily terrestrial material carried by turbiditic currents along the 800 km channel, and deposited at depths of up to nearly 5000 m. In this paper, we explore the effect of this carbon enrichment of deep-sea sediments on benthic macrofauna, along the prograding lobes fed by the current... |
Tipo: Text |
Palavras-chave: Chemosynthesis-based ecosystems; Cold seeps; Organic rich sediments; Macrofaunal communities. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00384/49561/50053.pdf |
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Cruaud, Perrine; Vigneron, Adrien; Pignet, Patricia; Caprais, Jean-claude; Lesongeur, Francoise; Toffin, Laurent; Godfroy, Anne; Cambon-bonavita, Marie-anne. |
In the Guaymas Basin, the presence at a few tens of kilometers of cold seeps and hydrothermal vents coupled with comparable sedimentary settings and depths offer a unique opportunity to assess and compare the microbial community composition of these deep-sea ecosystems. The microbial diversity in sediments from three cold seep and two hydrothermal vent assemblages were investigated using high-throughput 16S rRNA-sequencing. Numerous bacterial and archaeal lineages were detected in both cold seep and hydrothermal vent sediments. Various potential organic matter degraders (e.g., Chloroflexi, Atribacteria, MBG-D) and methane and sulfur cycling related microorganisms (e.g., ANME and methanogenic lineages, sulfate-reducing lineages) were detected in both... |
Tipo: Text |
Palavras-chave: Microbial diversity; Hydrothermal vents; Cold seeps; Ribotypes; Methane; Extreme environments. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00415/52640/53496.pdf |
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Portail, Marie; Olu, Karine; Escobar-briones, E.; Caprais, Jean-claude; Menot, Lenaick; Waeles, Mathieu; Cruaud, Perrine; Sarradin, Pierre-marie; Godfroy, Anne; Sarrazin, Jozee. |
Understanding the ecological processes and connectivity of chemosynthetic deep-sea ecosystems requires comparative studies. In the Guaymas Basin (Gulf of California, Mexico), the presence of seeps and vents in the absence of a biogeographic barrier, and comparable sedimentary settings and depths offers a unique opportunity to assess the role of ecosystem-specific environmental conditions on macrofaunal communities. Six seep and four vent assemblages were studied, three of which were characterised by common major foundation taxa: vesicomyid bivalves, siboglinid tubeworms and microbial mats. Macrofaunal community structure at the family level showed that density, diversity and composition patterns were primarily shaped by seep- and vent-common abiotic... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00280/39076/37642.pdf |
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Khripounoff, Alexis; Caprais, Jean-claude; Le Bruchec, Julie; Rodier, Philippe; Noel, Philippe; Cathalot, Cecile. |
The submarine canyons of the Brittany continental slope (Bay of Biscay–Northeast Atlantic) were studied to describe the conditions in which cold-water corals occur in these areas and their consequences for coral metabolism. Near-bottom current, oxygen, temperature, and particle flux, simultaneously measured for 2 yr at 850 m depth, revealed by spectral analysis the presence of several frequencies with a dominant semidiurnal tidal cycle and a current direction determined exclusively by the canyon topography. Sediment trap data also showed a seasonal input of material with a large peak of particles and carbon fluxes at the end of winter. Daily particle and carbon fluxes at 20 m above the bottom were 2.49 g m−2 d−1 and 20 mg C m−2 d−1, respectively. At the... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00173/28380/26695.pdf |
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Martin, Jean-louis; Marchand, Michel; Le Guellec, Anne-marie; Caprais, Jean-claude. |
Analyses of pesticides, polychlorobiphenyls (PCB's) and hydrocarbons have been carried out in sediments and water samples from the bays of Jakarta, Banten and Cilacap. Heavy metals (Hg, Cu, Mn, Zn, Fe, Pb, Cd, Ni, Co and Cr) have been analysed in sediment samples fram the same areas. - Organic pollutants : The results show that for pesticides, PCB and hydrocarbons, in water and in sediments, there is no significant pollution for the bays of Banten, Cilacap and Jakarta. The bay of Banten, where most of the concentrations are under the detection limits, that is ta say 2 ug/kg for the sediment and 2 ng/1 for the sea water, can be considered as a reference area. For total hydrocarbons and DDT, the bays of Cilacap and Jakarta show concentrations which can be... |
Tipo: Text |
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Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/00094/20546/18217.pdf |
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Gru, Cecile; Sarradin, Pierre-marie; Legoff, Hélène; Narcon, Sandrine; Caprais, Jean-claude; Lallier, Francois. |
This paper describes a method for the determination of reduced sulfur compounds in hydrothermal seawater and body fluids from the hydrothermal tube worm Riftia pachyptila. Sulfur is a hey component of the hydrothermal ecosystem based on chemosynthesis, Sulfur compounds were derivatized at pH 8 (4.3 for sulfide in biological fluid) with a fluorescent reagent, monobromobimane, and separated by reverse-phase HPLC. The eluted compounds were detected by spectrofluorimetry. This method allowed: the quantitative analysis of sulfide, sulfite, thiosulfate, cysteine and glutathione in seawater, vascular blood and coelomic fluids from R, pachyptila, The detection limits were in the 0.1 mu mol l(-1) range with a precision lower than 10%, The method has been applied to... |
Tipo: Text |
Palavras-chave: Sulfide; Sulfite; Thiosulfate; Cysteine; Glutathione; Hydrothermal seawater; Riftia pachyptila; Biological fluids. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00186/29763/28203.pdf |
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Sarradin, Pierre-marie; Lannuzel, D; Waeles, M; Crassous, Philippe; Le Bris, Nadine; Caprais, Jean-claude; Fouquet, Yves; Fabri, Marie-claire; Riso, R. |
The distribution of Fe, Cu, Zn, Pb, Cd between the dissolved (<2 mu m) and the particulate (>2 mu m) fractions was measured after in-situ filtration in two hydrothermal habitats. The total metal concentration ranges exhibit a clear enrichment compared with the seawater concentration, accounting for the hydrothermal input for all the metals considered. Iron is the predominant metal (5-50 mu M) followed by Zn and Cu. Cd and Pb are present at the nM level. At the scale studied, the behavior of temperature, pH and dissolved iron is semi-conservative whereas the other dissolved and particulate metals are characterized by non-conservative patterns. The metal enrichment of the >2 mu m fraction results from the settlement and accumulation of particulate... |
Tipo: Text |
Palavras-chave: Hydrothermal fauna; Habitats; Particulate; Dissolved; Metals. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3830.pdf |
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Cambon-bonavita, Marie-anne; Nadalig, Thierry; Roussel, Erwan; Delage, Eloise; Duperron, Sebastien; Caprais, Jean-claude; Boetius, A.; Sibuet, Myriam. |
A giant 800-m-diameter pockmark named REGAB was discovered on the Gabon continental margin actively emitting methane at a water depth of 3200 m. The microbial diversity in sediments from four different assemblages of chemosynthetic organisms, Mytilidae, Vesicomyidae, Sibogliniclae and a bacterial mat, was investigated using comparative 16S rRNA gene sequence analysis. Aggregates of anaerobic methanotrophic archaea (ANME-2) and bacteria of the Desulfosarcina/Desulfococcus cluster were found in all four chemosynthetic habitats. Fluorescence in situ hybridization targeting the ANME-2/Desulfosarcina/Desulfococcus aggregates showed their presence few centimeters (3-5cm) below the surface of sediment. 16S rRNA gene sequences from all known marine ANME groups... |
Tipo: Text |
Palavras-chave: Microbial phylogeny; Faunal assemblage; Cold seep; Chemosynthetic ecosystems; AOM; REGAB. |
Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/2009/publication-7298.pdf |
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Duperron, Sebastien; Nadalig, Thierry; Caprais, Jean-claude; Sibuet, Myriam; Fiala Medioni, Aline; Amann, Rudolf; Dubilier, Nicole. |
Deep-sea mussels of the genus Bathymodiolus (Bivalvia: Mytilidae) harbor symbiotic bacteria in their gills and are among the dominant invertebrate species at cold seeps and hydrothermal vents. An undescribed Bathymodiolus species was collected at a depth of 3,150 m in a newly discovered cold seep area on the southeast Atlantic margin, close to the Zaire channel. Transmission electron microscopy, comparative 16S rRNA analysis, and fluorescence in situ hybridization indicated that this Bathymodiolus sp. lives in a dual symbiosis with sulfide- and methane-oxidizing bacteria. A distinct distribution pattern of the symbiotic bacteria in the gill epithelium was observed, with the thiotrophic symbiont dominating the apical region and the methanotrophic symbiont... |
Tipo: Text |
Palavras-chave: Gabon; Southeast Atlantic; Methane seep; Hydrothermal vent; Deep sea; RRNA analysis; Methane concentration; Gill epithelium; Symbiosis; Bacteria; Mytilidae. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1266.pdf |
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Registros recuperados: 67 | |
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