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Registros recuperados: 102 | |
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Riou, V.; Halary, S.; Duperron, S.; Bouillon, S.; Elskens, M.; Bettencourt, R.; Santos, R. S.; Dehairs, F.; Colaco, A.. |
High densities of mussels of the genus Bathymodiolus are present at hydrothermal vents of the Mid-Atlantic Ridge. It was previously proposed that the chemistry at vent sites would affect their sulphide- and methane-oxidizing endosymbionts' abundance. In this study, we confirmed the latter assumption using fluorescence in situ hybridization on Bathymodiolus azoricus specimens maintained in a controlled laboratory environment at atmospheric pressure with one, both or none of the chemical substrates. A high level of symbiosis plasticity was observed, methane-oxidizers occupying between 4 and 39% of total bacterial area and both symbionts developing according to the presence or absence of their substrates. Using (HCO3-)-C-13 in the presence of sulphide, or... |
Tipo: Text |
Palavras-chave: Mid-atlantic ridge; Hydrocarbon-seep mussel; Deep-sea mussels; Hydrothermal-vent; Puteoserpentis bivalvia; Mytilidae; Methane; Endosymbionts; Bacteria; Metabolism. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00207/31865/30271.pdf |
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Morita, R; Jones, R. |
The nitrifying bacteria were found to survive 24 weeks in the absence of ammonium without decreasing their number of cell size. Because H sub(2), CO, and CH sub(4) are present in the marine environment, these substrates were investigated as a possible source of the energy of maintenance for the nitrifying bacteria. super(14)CO and super(14)CH sub(4) were found to be oxidized by the nitrifiers. N-serve was found to inhibit the oxidation of CO. Using the nitrifiers' ability to oxide CO, a method for the determination of the nitrification rate was developed. The ability of nitrifiers to oxidize CO may play a significant role in the cycling of CO sub(2) in the marine environment. Whether CO and CH sub(4) oxidation play a role in the survival of nitrifiers in... |
Tipo: Text |
Palavras-chave: Methane; Carbon dioxide; Survival; Bacteria; Nitrification; Nitrogen cycle; Oxidation; Carbon cycle; Biogeochemistry; Metabolism. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-975.pdf |
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Lima,Magda Aparecida de; Vieira,Rosana Faria; Frighetto,Rosa Toyoko Shiraishi; Luiz,Alfredo José Barreto; Villela,Omar Vieira. |
ABSTRACT: Local greenhouse gas flow measurement studies have been encouraged at a global level as a subsidy for national and state inventories. This study aimed to evaluate the seasonal methane emission during the 2008/2009 harvest, from an irrigated rice plantation, under pre-germinated system, in the municipality of Tremembé, State of São Paulo, using the static chamber technique and gas chromatography. The study showed high seasonal emission of methane (CH4) for the studied area, probably due to the long flooding period. It was estimated the CH4 emission factor (6.51 kg CH4 ha-1 dia-1), the partial global warming potential (pGWP, 27.2 Mg CO2eq growing season-1 ha-1) and the yield-scaled pGWP (YpGWP, 3.9 kg CO2eq kg-1 grain). |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Flooded rice; Pre-germinated system; Methane. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019001100201 |
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Graves, Carolyn A.; James, Rachael H.; Sapart, Celia Julia; Stott, Andrew W.; Wright, Ian C.; Berndt, Christian; Westbrook, Graham; Connelly, Douglas P.. |
Offshore western Svalbard plumes of gas bubbles rise from the seafloor at the landward limit of the gas hydrate stability zone (LLGHSZ; ∼400 m water depth). It is hypothesized that this methane may, in part, come from dissociation of gas hydrate in the underlying sediments in response to recent warming of ocean bottom waters. To evaluate the potential role of gas hydrate in the supply of methane to the shallow subsurface sediments, and the role of anaerobic oxidation in regulating methane fluxes across the sediment-seawater interface, we have characterised the chemical and isotopic compositions of the gases and sediment pore waters. The molecular and isotopic signatures of gas in the bubble plumes (C1/C2+ = 1 × 104; δ13C-CH4 = -55 to -51 ‰; δD-CH4 = -187... |
Tipo: Text |
Palavras-chave: Methane; Seafloor sediments; Gas hydrate; Offshore Svalbard; Seabed fluxes; Anaerobic oxidation. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00358/46914/46819.pdf |
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Akhoudas, C.; Chevalier, N.; Blanc-valleron, M. -m.; Klein, V.; Mendez-millan, M.; Demange, J.; Dalliah, S.; Rommevaux, V.; Boudouma, O.; Pierre, C.; Ruffine, Livio. |
Cold seeps along the North Anatolian fault in the Sea of Marmara (Turkey) were explored during submersible dives of the Marsite cruise in November 2014 when sediments, pore waters and carbonate crusts were sampled at active fluid seeping sites. In this study, we investigate the mineralogy, carbon and oxygen isotopic compositions and the lipid biomarkers of a carbonate crust from the western Tekirdağ basin of the Sea of Marmara. This crust exhibits a laminated domal structure that resembles stromatolite. The mineralogy of authigenic seep-carbonate is mostly represented by aragonite associated with minor amounts of high-magnesian calcite. The abundance of pyrite associated with the authigenic seep-carbonate points to very intense bacterial sulfate reduction.... |
Tipo: Text |
Palavras-chave: Marmara Sea; Tekirdag Basin; Methane; Authigenic seep-carbonate; Sulfate reduction; Anaerobic oxidation of methane; Stromatolitic structure; Stable isotopes; Lipid biomarkers. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00417/52857/53764.pdf |
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Oliveira,Laís R. G. de; Santos Filho,Derovil A. dos; Vasconcelos,Kaline C.; Lucena,Talita V. de; Jucá,José F. T.; Santos,André F. de M. S.. |
ABSTRACT Anaerobic biodigestion of solid and semi-solid wastes has been widely used for the treatment of these residues and methane production; however, during the process (more specifically in the acidogenic phase), there is a tendency of pH reduction, an unfavorable condition to methanogenic bacteria. Thus, the present work aims to evaluate the methanization potential of an agroindustrial anaerobic granular sludge (AIS) from UASB (Upflow Anaerobic Sludge Blanket) reactor, individually and biodigested with food waste (FW) from the University Restaurant of the Federal University of Pernambuco with buffering agent (AIS + FW + b) and without it (AIS + FW). After the laboratory tests, the AIS + FW + b configuration obtained a cumulative methane production... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biodegradation; Methane; PH; Inoculum. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000100069 |
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Pastor, Lucie; Brandily, Christophe; Schmidt, S.; Miramontes, E.; Péron, Maela; Appere, Dennis; Chéron, Sandrine; Boissier, Audrey; Jouet, Gwenael. |
The NW Madagascar continental margin receives high loads of terrigenous particulate organic matter during the wet season and especially linked to extreme events, originating from two major rivers, the Betsiboka and the Mahavavy Rivers. This particulate matter contains a high content of iron minerals from the weathering of red ferruginous/ferralitic soils of Madagascar. The presence of pockmarks, i.e. gas or fluid expulsion features on the continental slope, testifies to past/present methane migration through the sedimentary column, associated with early diagenetic processes. This study globally aims at deciphering the interactions between episodic sedimentation and geochemical processes influenced by fluids upward migration, using a sediment trap mooring... |
Tipo: Text |
Palavras-chave: Episodic sedimentation; Madagascar margin; Betsiboka river; Mahavavy river; Progradation; Methane; Geochemistry; Sediment. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00628/73964/73323.pdf |
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Ruffine, Livio; Ondreas, Helene; Blanc-valleron, Marie-madeleine; Teichert, Barbara M. A.; Scalabrin, Carla; Rinnert, Emmanuel; Birot, Dominique; Croguennec, Claire; Ponzevera, Emmanuel; Pierre, Catherine; Donval, Jean-pierre; Alix, Anne-sophie; Germain, Yoan; Bignon, Laurent; Etoubleau, Joel; Caprais, Jean-claude; Knoery, Joel; Lesongeur, Francoise; Thomas, Bastien; Roubi, Angelique; Legoix, Ludovic Nicolas; Burnard, Pete; Chevalier, Nicolas; Lu, Hailong; Dupre, Stephanie; Fontanier, Christophe; Dissard, Delphine; Olgun, Nazli; Yang, Hailin; Strauss, Harald; Ozaksoy, Volkan; Perchoc, Jonathan; Podeur, Christian; Tarditi, Corinne; Ozbeki, Eyyup; Guyader, Vivien; Marty, Bernard; Madre, David G; Pitel-roudaut, Mathilde; Grall, Celine; Embriaco, Davide; Polonia, Mina; Gasperini, Lucas; Cagatay, M. Namik; Henry, Pierre; Geli, Louis. |
MarsiteCruise was undertaken in October/November 2014 in the Sea of Marmara to gain detailed insight into the fate of fluids migrating within the sedimentary column and partially released into the water column. The overall objective of the project was to achieve a more global understanding of cold-seep dynamics in the context of a major active strike-slip fault. Five remotely operated vehicle (ROV) dives were performed at selected areas along the North Anatolian Fault and inherited faults. To efficiently detect, select and sample the gas seeps, we applied an original procedure. It combines sequentially (1) the acquisition of ship-borne multibeam acoustic data from the water column prior to each dive to detect gas emission sites and to design the tracks of... |
Tipo: Text |
Palavras-chave: Acoustic survey; Authigenic carbonates; Biogeochemistry; Chemical analyses; Cold seeps; Dissolved major elements; Fluid seepage; Geology; In situ Raman analysis; Methane; ROV dives. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00433/54434/55783.pdf |
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Zbinden, M; Shillito, B; Le Bris, Nadine; De Montlaur, C; Roussel, Erwan; Guyot, F; Gaill, F; Cambon-bonavita, Marie-anne. |
The Rimicaris exoculata dominates the megafauna of some of the Mid Atlantic ridge hydrothermal vent sites. This species harbors a rich community of bacterial epibionts inside its gill chamber. Literature data indicate that a single 16S rRNA phylotype dominates this epibiotic community, and is assumed to be a sulfide-oxidizing bacteria. However attempts Of Cultivation were not successful and did not allow to confirm it. The aim of our study was to test the hypothesis of sulfide oxidation in the gill chamber, by a multidisciplinary approach, using in vivo experiments at in situ pressure in the presence of sulfide, microscopic observations and a molecular survey. Morphology of microorganisms, before and after treatment, was analyzed to test the effect of... |
Tipo: Text |
Palavras-chave: Sulfur; Methane; Iron; Intracellular granules; Hydrothermal vent shrimp; High pressure experiments. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4563.pdf |
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Eickenbusch, Philip; Takai, Ken; Sissman, Olivier; Suzuki, Shino; Menzies, Catriona; Sakai, Sanae; Sansjofre, Pierre; Tasumi, Eiji; Bernasconi, Stefano M.; Glombitza, Clemens; Jorgensen, Bo Barker; Morono, Yuki; Lever, Mark Alexander. |
Serpentinitic systems are potential habitats for microbial life due to frequently high concentrations of microbial energy substrates, such as hydrogen (H-2), methane (CH4), and short-chain organic acids (SCOAs). Yet, many serpentinitic systems are also physiologically challenging environments due to highly alkaline conditions (pH > 10) and elevated temperatures (>80 degrees C). To elucidate the possibility of microbial life in deep serpentinitic crustal environments, International Ocean Discovery Program (IODP) Expedition 366 drilled into the Yinazao, Fantangisfia, and Asut Tesoru serpentinite mud volcanoes on the Mariana Forearc. These mud volcanoes differ in temperature (80, 150, 250 degrees C, respectively) of the underlying subducting slab, and... |
Tipo: Text |
Palavras-chave: Limits of life; Deep biosphere; Serpentinization; Abiotic synthesis; Formate; Acetate; Methane; International Ocean Discovery Program. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00637/74919/75981.pdf |
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Bruno,Marcelo; Oliveira,Roberto A. de. |
In this study it was evaluated the efficiency of the treatment of wet-processed coffee wastewater in upflow anaerobic sludge blanket (UASB) reactors in two stages, in bench scale, followed by post-treatment with activated sludge in batch. The first UASB reactor was submitted to an hydraulic retention time (HRT) of 6.2 d and organic loading rates (OLR) of 2.3 and 4.5g CODtotal (L d)-1, and the second UASB reactor to HRT of 3.1 d with OLR of 0.4 and 1.4g CODtotal (L d)-1. The average values of the affluent CODtotal increased from 13,891 to 27,926mg L-1 and the average efficiencies of removal of the CODtotal decreased from 95 to 91%, respectively, in the UASB reactors in two stages. The volumetric methane production increased from 0.274 to 0.323L CH4 (L... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anaerobic digestion; Methane; Nitrogen; Phosphorus; Phenols. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000400020 |
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Pineda,Gloria Stefanny Hernández; Beltrán,Paulina Elizabeth Pedraza; Benaouda,Mohammed; García,José Manuel Palma; Nova,Francisca Avilés; Molina,Luisa; Ortega,Octavio Alonso Castelán. |
ABSTRACT: The aim of the present research was to evaluate the effect of Pithecellobium dulce, Tagetes erecta and Cosmos bipinnatus on methane emission, milk yield and dry matter intake in dairy cattle. A 4×4 Latin square experimental design was employed, using four multiparous Holstein cows of 553±72.4kg body weight, at mid lactation and average milk yield of 17.3±3kg/day. The experiment lasted 92 days, divided into four experimental periods of 23 days each. All cows had free access to maize and alfalfa silage in a 50:50 proportion, 4kg of concentrate/day and ad libitum access to water. Treatments consisted in supplementation of 0.5kg/day of the experimental plants, with one control treatment without supplementation. Each cow received one of each treatment... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Methane; Cattle; Climate change; Mitigation; Tannins. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018001000650 |
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Dubois, Stanislas; Derian, Francois; Caisey, Xavier; Rigolet, Carinne; Caprais, Jean-claude; Thiebaut, Eric. |
We used existing bathymetric data to study the macrofauna of a geophysical pockmark field restricted to a benthic habitat engineered by the tubiculous amphipod Haploops nirae in South Brittany (France). Stations inside and outside pockmarks of different morphometric characteristics (location, size, depression depth) were sampled for macrofauna and environmental parameters (sediment characteristics, organic matter, chl a, hydrogen sulfide and methane concentrations). Diversity indices showed higher species richness inside pockmarks, especially for species with medium to high abundances. Most sediment cores showed low methane but high hydrogen sulfide concentrations. We hypothesised that after eruption, the remaining residual methane from pockmark sediments... |
Tipo: Text |
Palavras-chave: Benthic habitat; Biodiversity; Succession; Amphipod; Haploops; South Brittany; Sulfide; Methane; Environmental factors. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00272/38333/36576.pdf |
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Dupre, Stephanie; Woodside, J; Foucher, Jean-paul; De Lange, G; Mascle, J; Boetius, A; Mastalerz, V; Stadnitskaia, A; Ondreas, Helene; Huguen, C; Harmegnies, Francois; Gontharet, Swanne; Loncke, L; Deville, E; Niemann, H; Omoregie, E; Olu, Karine; Fiala Medioni, A; Dahlmann, A; Caprais, Jean-claude; Prinzhofer, A; Sibuet, Myriam; Pierre, C; Damste, J. |
Four mud volcanoes of several kilometres diameter named Amon, Osiris, Isis, and North Alex and located above gas chimneys on the Central Nile Deep Sea Fan, were investigated for the first time with the submersible Nautile. One of the objectives was to characterize the seafloor morphology and the seepage activity across the mud volcanoes. The seepage activity was dominated by emissions of methane and heavier hydrocarbons associated with a major thermal contribution. The most active parts of the mud volcanoes were highly gas-saturated (methane concentrations in the water and in the sediments, respectively, of several hundreds of nmol/L and several mmol/L of wet sediment) and associated with significantly high thermal gradients (at 10 m below the seafloor,... |
Tipo: Text |
Palavras-chave: Seafloor morphology; Methane; Authigenic carbonate precipitation; Gas chimneys; Mud breccia; Mud volcanoes; Fluid seepage; Nile fan. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4455.pdf |
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Pape, Thomas; Ruffine, Livio; Hong, Wei‐li; Sultan, Nabil; Riboulot, Vincent; Peters, Carl A.; Kölling, Martin; Zabel, Matthias; Garziglia, Sebastien; Bohrmann, Gerhard. |
The evolution of submarine pockmarks is often related to the ascent of fluid from the subsurface. For pockmarks located within the gas hydrate stability zone, methane oversaturation can result in the formation of gas hydrates in the sediment. A ca. 600 m‐wide sea floor depression in deep‐waters offshore Nigeria, Pockmark A, was investigated for distributions and quantities of shallow gas hydrates, origins of hydrocarbons and time elapsed since the last major fluid ascent event. For the first time, pressure coring of shallow sediments and drilling of more than 50‐m‐long cores with the sea floor drill rig MARUM‐MeBo70 were conducted in this pockmark. Unusually high hydrate saturations of up to 51% of pore volume in the uppermost 2.5 meters of sediment in the... |
Tipo: Text |
Palavras-chave: Pockmark; Gas hydrate; Methane; MeBo; Pressure coring; Pore water modeling. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00643/75491/76344.pdf |
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Registros recuperados: 102 | |
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