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Registros recuperados: 12 | |
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Vanreusel, Ann; Andersen, Ann C.; Boetius, Antje; Connelly, Douglas; Cunha, Marina R.; Decker, Carole; Hilario, Ana; Kormas, Konstantinos Ar.; Maignien, Lois; Olu, Karine; Pachiadaki, Maria; Ritt, Benedicte; Rodrigues, Clara; Sarrazin, Jozee; Tyler, Paul; Van Gaever, Saskia; Vanneste, Heleen. |
During the European Commission's Framework Six Programme, HERMES, we investigated three main areas along the European margin, each characterized by the presence of seep-related structures exhibiting different intensity of activity and biological diversity. These areas are: (1) the Nordic margin with the Hakon Mosby mud volcano and many pockmarks, (2) the Gulf of Cadiz, and (3) the eastern Mediterranean with its hundreds of mud volcanoes and brine pool structures. One of the main goals of the HERMES project was to unravel the biodiversity associated with these seep-associated ecosystems, and to understand their driving forces and functions, using an integrated approach. Several multidisciplinary research cruises to these three areas provided evidence of... |
Tipo: Text |
Palavras-chave: Mosby mud volcano; Gulf of mexico; Cadiz ne atlantic; Deep sea fan; Community structure; Microbial communities; Fluid flow; Mediterranean sea; Carbonate crusts; Norwegian sea. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6375.pdf |
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Losekann, Tina; Knittel, Katrin; Nadalig, Thierry; Fuchs, Bernhard; Niemann, Helge; Boetius, Antje; Amann, Rudolf. |
Submarine mud volcanoes are formed by expulsions of mud, fluids, and gases from deeply buried subsurface sources. They are highly reduced benthic habitats and often associated with intensive methane seepage. In this study, the microbial diversity and community structure in methane-rich sediments of the Haakon Mosby Mud Volcano (HMMV) were investigated by comparative sequence analysis of 16S rRNA genes and fluorescence in situ hybridization. In the active volcano center, which has a diameter of about 500 m, the main methane-consuming process was bacterial aerobic oxidation. In this zone, aerobic methanotrophs belonging to three bacterial clades closely affiliated with Methylobacter and Methylophaga species accounted for 56% +/- 8% of total cells. In... |
Tipo: Text |
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Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2617.pdf |
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Ritt, Benedicte; Pierre, Catherine; Gauthier, Olivier; Wenzhoefer, Frank; Boetius, Antje; Sarrazin, Jozee. |
The Nile Deep-Sea Fan (NDSF) is located on the passive continental margin off Egypt and is characterized by the occurrence of active fluid seepage such as brine lakes, pockmarks and mud volcanoes. This study characterizes the structure of faunal assemblages of such active seepage systems of the NDSF. Benthic communities associated with reduced, sulphidic microhabitats such as sediments and carbonate crusts were sampled by remotely operated vehicles during two cruises in 2006 (BIONIL) and 2007 (MEDECO). Environmental conditions and biological factors including family-level faunal composition, density and diversity were measured at local and regional scales. Significant differences were detected at different spatial scales: (1) the fauna of reduced habitats... |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00037/14798/12212.pdf |
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Gobet, Angelique; Boeer, Simone I.; Huse, Susan M.; Van Beusekom, Justus E. E.; Quince, Christopher; Sogin, Mitchell L.; Boetius, Antje; Ramette, Alban. |
Coastal sands filter and accumulate organic and inorganic materials from the terrestrial and marine environment, and thus provide a high diversity of microbial niches. Sands of temperate climate zones represent a temporally and spatially highly dynamic marine environment characterized by strong physical mixing and seasonal variation. Yet little is known about the temporal fluctuations of resident and rare members of bacterial communities in this environment. By combining community fingerprinting via pyrosequencing of ribosomal genes with the characterization of multiple environmental parameters, we disentangled the effects of seasonality, environmental heterogeneity, sediment depth and biogeochemical gradients on the fluctuations of bacterial communities... |
Tipo: Text |
Palavras-chave: 454 pyrosequencing; Coastal seas; Bacterial diversity; Multivariate analysis; Rare biosphere. |
Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00488/59947/63192.pdf |
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Gobet, Angelique; Boetius, Antje; Ramette, Alban. |
Changes in richness and bacterial community structure obtained via 454 Massively Parallel Tag Sequencing (MPTS) and Automated Ribosomal Intergenic Analysis (ARISA) were systematically compared to determine whether and how the ecological knowledge obtained from both molecular techniques could be combined. We evaluated community changes over time and depth in marine coastal sands at different levels of taxonomic resolutions, sequence corrections and sequence abundances. Although richness over depth layers or sampling dates greatly varied [approximate to 30% and 70-80% new operational taxonomic units (OTU) between two samples with ARISA and MPTS respectively], overall patterns of community variations were similar with both approaches. Alpha-diversity... |
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Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00488/59943/63180.pdf |
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Feseker, Tomas; Boetius, Antje; Wenzhofer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R.; Camilli, Richard; German, Christopher R.; De Beer, Dirk. |
Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Hakon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the... |
Tipo: Text |
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Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00245/35601/34137.pdf |
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Bayon, Germain; Dupre, Stephanie; Ponzevera, Emmanuel; Etoubleau, Joel; Cheron, Sandrine; Pierre, Catherine; Mascle, Jean; Boetius, Antje; De Lange, Gert J.. |
Marine sediments at ocean margins vent substantial amounts of methane(1,2). Microbial oxidation of the methane released can trigger the precipitation of carbonate within sediments and support a broad diversity of seafloor ecosystems(3,4). The factors controlling microbial activity and carbonate precipitation associated with the seepage of submarine fluid over geological time remain poorly constrained. Here, we characterize the petrology and geochemistry of rocks sampled from metre-size build-ups of methane-derived carbonate chimneys located at the Amon mud volcano on the Nile deep-sea fan. We find that these carbonates comprise porous structures composed of aggregated spherules of aragonite, and closely resemble microbial carbonate reefs forming at present... |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26734/24854.pdf |
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Sauter, Eberhard; Muyakshin, Sergey; Charlou, Jean-luc; Schluter, Michael; Boetius, Antje; Jerosch, Kerstin; Damm, Ellen; Foucher, Jean-paul; Klages, Michael. |
The assessment of climate change factors includes a constraint of methane sources and sinks. Although marine geological Sources are recognized as significant, unfortunately, most submarine sources remain poorly quantified. Beside cold vents and coastal anoxic sediments, the large number of submarine mud volcanoes (SMV) may contribute significantly to the oceanic methane pool. Recent research suggests that methane primarily released diff-usively from deep-sea SMVs is immediately oxidized and, thus, has little climatic impact. New hydro-acoustic, Visual, and geochemical observations performed at the deep-sea mud volcano Hakon Mosby reveal the discharge of gas hydrate-coated methane bubbles and gas hydrate flakes forming huge methane plumes extending from... |
Tipo: Text |
Palavras-chave: Hydro acoustics; Gas hydrates; Gas bubbles; Submarine mud volcanoes; Methane budget; Plume; Methane sources. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1345.pdf |
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Omoregie, Enoma O.; Niemann, Helge; Mastalerz, Vincent; De Lange, Gert J.; Stadnitskaia, Alina; Mascle, Jean; Foucher, Jean-paul; Boetius, Antje. |
The Eastern Mediterranean hosts a variety of active cold seep systems, such as gas chimneys, mud volcanoes and pockmarks, in water depths of 500 to 3200 m. As part of the NAUTINIL expedition in 2003, the sediments of cold seeps on the Nile Deep Sea Fan (NDSF) were sampled for the first time for biogeochemical and microbiological analyses. Here we compare rates of the anaerobic oxidation of methane (AOM) and sulfate reduction (SR) as well as the microbial community structure of a variety of cold seep systems including mud volcanoes, pockmarks and brine seeps. Our results revealed strong differences in microbial activity among the different seep systems of the Eastern, Central and Western provinces of the NDSF, as well as the Olimpi field (Central... |
Tipo: Text |
Palavras-chave: Methane oxidation; Sulfate reduction; Archaea; Cold seeps; Mud volcano; Pockmarks; Nile Deep Sea Fan. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00000/11087/7910.pdf |
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Foucher, Jean-paul; Westbrook, Graham K.; Boetius, Antje; Ceramicola, Silvia; Dupre, Stephanie; Mascle, Jean; Mienert, Jurgen; Pfannkuche, Olaf; Pierre, Catherine; Praeg, Daniel. |
Submarine hydrocarbon seeps are geologically driven "hotspots" of increased biological activity on the seabed. As part of the HERMES project, several sites of natural hydrocarbon seepage in the European seas were investigated in detail, including mud volcanoes and pockmarks, in study areas extending from the Nordic margin, to the Gulf of Cadiz, to the Mediterranean and Black seas. High-resolution seabed maps and the main properties of key seep sites are presented here. Individual seeps show ecosystem zonation related to the strength of the methane flux and distinct biogeochemical processes in surface sediments. A feature common to many seeps is the formation of authigenic carbonate constructions. These constructions exhibit various morphologies ranging... |
Tipo: Text |
Palavras-chave: Mosby mud volcano; Deep sea fan; Eastern mediterranean sea; Black sea; Anaerobic oxidation; Hydrocarbon seeps; Carbonate crusts; Sidescan sonar; Hydrate ridge; Gas chimneys. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6387.pdf |
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Registros recuperados: 12 | |
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