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Registros recuperados: 102 | |
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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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Bernoux,Martial; Branca,Giacomo; Carro,Aude; Lipper,Leslie; Smith,Garry; Bockel,Louis. |
EX-ACT (EX-Ante Carbon-balance Tool) is a tool developed by the Food and Agriculture Organization of the United Nations (FAO). It provides ex-ante measurements of the mitigation impact of agriculture and forestry development projects, estimating net C balance from GHG emissions and Carbon (C) sequestration. EX-ACT is a land-based accounting system, measuring C stocks, stock changes per unit of land, and CH4 and N2O emissions expressed in t CO2-eq per hectare and year. The main output of the tool is an estimation of the C-balance associated with the adoption of improved land management options, as compared with a "business as usual" scenario. EX-ACT has been developed using primarily the IPCC 2006 Guidelines for National Greenhouse Gas Inventories,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mitigation; Nitrous oxide; Methane; C sequestration; Land use change and forestry. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000100005 |
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Blouin, Arthur; Imbert, Patrice; Sultan, Nabil; Callot, Jean-paul. |
The morphology of mud volcanoes (MV) has been extensively studied over the last few decades. Although recent research has begun to focus on deep processes and structures, little is known about mud generation mechanisms. This study aims to investigate the feeder system and formation of an active kilometer‐scale MV by relying on a 3‐D seismic survey and an in‐situ dataset on the Absheron anticline (South Caspian Basin). Seismic data show a depleted area in the Anhydritic Surakhany Formation (ASF), whose mineralogical composition fits with surface mud. Well data show that the ASF is a succession of evaporitic beds and low temperature shales near its fracture pressure. Biostratigraphic analysis confirms a Pliocene origin for the mud, suggesting that the ASF... |
Tipo: Text |
Palavras-chave: Mud volcano; Pore pressure; Methane; Modeling; Seismic. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00481/59304/62057.pdf |
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Boulart, Cedric; Chavagnac, Valerie; Monnin, Christophe; Delacour, Adelie; Ceuleneer, Georges; Hoareau, Guilhem. |
Serpentinisation of mantle rocks, leading to natural venting of hydrogen and methane, has been reported to occur at the global scale, wherever fluids percolate in ultramafic formations. Here we compare gas composition from two on-land, low-temperature, and hyper-alkaline springs hosted on ultramafic rocks in the ophiolite massifs of the Sultanate of Oman and the Ligurian Alps (Voltri Group, Genoa region, Northern Italy). These two settings exhibit similar chemical and mineralogical features but show diverse styles of gas venting. Commonly to all hyper-alkaline springs, gases are characterised by relatively high N-2, very low O-2 and CO2 concentrations, and a strong enrichment in H-2 and CH4. The comparison between Oman and Liguria highlights a high... |
Tipo: Text |
Palavras-chave: Methane; Hydrogen; Gas composition; Hyper-alkaline springs. Oman; Voltri Massif. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00175/28634/27059.pdf |
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Bréchet, Laëtitia; Courtois, Elodie A.; Saint-germain, Thomas; Janssens, Ivan A.; Asensio, Dolores; Ramirez-rojas, Irene; Soong, Jennifer L.; Van Langenhove, Leandro; Verbruggen, Erik; Stahl, Clément. |
Tropical soils are a major contributor to the balance of greenhouse gas (GHG) fluxes in the atmosphere. Models of tropical GHG fluxes predict that both the frequency of drought events and changes in atmospheric deposition of nitrogen (N) will significantly affect dynamics of soil carbon dioxide (CO2) and methane (CH4) production and consumption. In this study, we examined the combined effect of a reduction in precipitation and an increase in nutrient availability on soil CO2 and CH4 fluxes in a primary French Guiana tropical forest. Drought conditions were simulated by intercepting precipitation falling through the forest canopy with tarpaulin roofs. Nutrient availability was manipulated through application of granular N and/or phosphorus (P) fertilizer to... |
Tipo: Text |
Palavras-chave: Carbon dioxide; Drought; Fertilization; Methane; Nitrogen; Phosphorus; Soil GHG fluxes; Tropical forest. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00595/70694/68903.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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Castillo Rangel,Francisco; Villalobos Villalobos,Guillermo; Domínguez Díaz,David; Ortega Gutiérrez,Juan Ángel. |
ABSTRACT The objective was to evaluate the effect of three levels of cull pinto beans (CPB; Phaseolus vulgaris) on ruminal fermentation, kinetics, and nutrient digestibility in hair lambs. Six cannulated lambs averaging 56.6±3.8 kg were used and were randomly assigned to one of three treatments. Treatments were: 0.0 kg kg−1 of CPB in the supplement (control); 0.25 kg kg−1 of CPB in the supplement (CB25); and 0.40 kg kg−1 of CPB in the supplement (CB40). Dry matter intake, ruminal pH, NH3, and volatile fatty acid (VFA) concentration, methane production, Kp (passage rate), MRT (mean retention time), and digestibility of dry matter, crude protein, and neutral detergent fiber were evaluated. Data were analyzed in a Latin square design, repeated in line, by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ammonia; Legumes; Methane; Ruminal pH; Sheep; Volatile fatty acids. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982017000500405 |
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Chiaradia,Jonas Jacob; Chiba,Marcio Koiti; Andrade,Cristiano Alberto de; Carmo,Janaína Braga do; Oliveira,Claudeir de; Lavorenti,Arquimedes. |
Organic residue application into soil alter the emission of gases to atmosphere and CO2, CH4, N2O may contribute to increase the greenhouse effect. This experiment was carried out in a restoration area on a dystrophic Ultisol (PVAd) to quantify greenhouse gas (GHG) emissions from soil under castor bean cultivation, treated with sewage sludge (SS) or mineral fertilizer. The following treatments were tested: control without N; FertMin = mineral fertilizer; SS5 = 5 t ha-1 SS (37.5 kg ha-1 N); SS10 = 10 t ha-1 SS (75 kg ha-1 N); and SS20 = 20 t ha-1 SS (150 kg ha-1 N). The amount of sludge was based on the recommended rate of N for castor bean (75 kg ha-1), the N level of SS and the mineralization fraction of N from SS. Soil gas emission was measured for 21... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Residue; Nitrogen; Carbon dioxide; Nitrous oxide; Methane. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600035 |
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Chiemchaisri,Wilai; Visvanathan,Chettiyappan; Jy,Shing Wu. |
The effects of volatile organic compounds (VOCs) on methane oxidation in landfill cover soils were examined. The batch experiments were conducted using single and mixed VOCs, such as, dichloromethane (DCM), trichloroethylene (TCE), tetrachloroethylene (PCE), and benzene. The results from all combinations showed a decrease in methane oxidation rate with increase in VOC concentrations. Moreover, inhibition effects of TCE and DCM were found higher than benzene and PCE. The reduction of methane oxidation by benzene and PCE could be attributed to the toxicity effect, whereas TCE and DCM were found to exhibit the competitive-inhibition effect. When the soil was mixed with DCM, no methane oxidation was found. Damage to the cells internal membrane was found in a... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Landfill cover soils; Methane; Methanotrophs; Methane oxidation; Volatile organic compounds (VOCs). |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000200005 |
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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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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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Registros recuperados: 102 | |
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