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| Registros recuperados: 36 | |
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| Bertoni, R. |
| The radiochemical methods proposed for evaluating heterotrophic activity in waters have been severely criticized in recent years because they are not considered to be sufficiently realistic. Thus, the possibility of directly measuring the heterotrophic consumption of naturally occurring Organic Carbon (OC) in fresh water samples incubated under controlled conditions has been evaluated. The analytical performances of two OC analyzers utilizable for this purpose are discussed here, and some examples of the results obtained by the direct measurement of OC consumption are presented. The consumption rates thus measured ranged from 11.6 to 50.2 mu gC/ 1.h. Although the technique discussed here is less sensitive than radiochemical methods, the few assumptions... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Microbiology; Carbon cycle; Organic carbon; Water; Heterotrophic organisms; Analytical techniques. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-950.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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| Reichardt, W. |
| The predominantly anoxic, sulfide-rich sandy sediment of a shallow lagoon at Kiel Fjord was densely inhabited by the polychaete worm Nereis diversicolor (280 cm super(3) m super(-2) of biomass volume). Burrow walls which contrasted by their brown coloration of at least 1.5 mm thickness with the bulk of the reduced black sediment, made up for 6% of the total volume of the 10 cm cores investigated. Only the uppermost mm of the internal surface layer contained detectable O sub(2). As a result of the build up of internal redox gradients, CO sub(2) dark fixation was activated in the burrow walls (by a factor of approximately equals 2). Assays of ribulose-biphosphate carboxylase activities and viable counts of potentially chemoautotrophic bacteria in different... |
| Tipo: Text |
Palavras-chave: Nereis diversicolor; Polychaeta; Bacteria; Microorganisms; Carbon cycle; Tube dwellers; Carbon fixation; Burrows; Bioturbation; Sediments. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-990.pdf |
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| Jennerjahn, Tc; Ittekkot, V. |
| The nature of sedimentary organic matter from mangroves and the continental margin of eastern Brazil (8 degrees-24 degrees S) has been investigated in order to obtain information on sources and diagenetic processes. The organic matter content of mangrove sediments is three to four times higher than the maximum content of continental margin sediments. Downslope distribution of organic carbon, nitrogen, amino acids and hexosamines shows an enrichment in water depths between 800 m and 1000 m. The distribution of individual amino acids and hexosamines is highly variable in sedimentary organic matter from mangroves and the continental margin, and the observed compositional differences are mainly due to diagenetic alteration. Organic matter is highly reactive in... |
| Tipo: Text |
Palavras-chave: Organic carbon; Amino acids; Carbon cycle; Mangroves; Continental margin. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20403/18070.pdf |
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| Durrieu De Madron, X; Denis, L; Diaz, F; Garcia, N; Guieu, C; Grenz, C; Loye-pilot, Md; Ludwig, W; Moutin, T; Raimbault, P; Ridame, C. |
| Shelf-slope exchanges and budgets of organic and inorganic nutrients are calculated for the Gulf of Lion continental margin in the northwestern Mediterranean. Computations are based on data from three seasonal marine surveys performed in March 1998, June 1998 and January 1999 in the framework of the French Programme National d'Environnement Cotier. A Land-Ocean Interactions in the Coastal Zone type box model is used to calculate the advective exchanges between the shelf and the adjacent open sea and to estimate the budgets of non-conservative elements (DIP, DIN, DOP, DON, DOC, POC, PON, POP). These budgets consider river discharges, urban sewage supply, atmospheric deposition, and fluxes at the water-sediment and shelf-slope interfaces. Uncertainties on... |
| Tipo: Text |
Palavras-chave: Mer Méditerranée; Echanges côte-large; Fonctionnement de l’écosystème; Cycle du carbone; Bilan de sels nutritifs; Mediterranean Sea; Shelf-slope exchanges; Ecosystem functioning; Carbon cycle; Nutrients budget. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00301/41236/40426.pdf |
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| Touratier, Franck; Goyet, C; Coatanoan, Christine; Andrie, C. |
| With a limited number of properties (salinity, temperature, total dissolved inorganic carbon, total alkalinity, and oxygen) from a recent cruise in the tropical Atlantic Ocean, We use the simple and recent approach TrOCA (Tracer combining Oxygen, inorganic Carbon, and total Alkalinity) to estimate the distribution of anthropogenic CO2 along three latitudinal sections. In order to assess the quality of the anthropogenic CO2 distribution, results from the method are compared to the CFC-11 measurements. We discuss the large-scale distribution of the main water masses of the tropical Atlantic Ocean in the light of the anthropogenic CO2 and the CFC-11 distributions. Keeping in mind that the anthropogenic CO2 emission began similar to 60 years earlier than that... |
| Tipo: Text |
Palavras-chave: Tropical belt; Atlantic Ocean; Water mass; Carbon cycle. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-886.pdf |
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| Montalvo, J. F.; García, I.; Esponda, S.C.,; Cesar, M.E.; Alburquerque, O.. |
| Se realizaron cinco muestreos entre enero de 2007 y junio de 2008 a la zona costera del municipio Playa, con el fin de evaluar los contenidos de los compuestos del ciclo del carbono. Los parámetros estudiados en la matriz agua fueron carbón orgánico, pH, alcalinidad total, alcalinidad al carbonato, dióxido de carbono total, dióxido de carbono libre, presión parcial de CO2, y contenidos de bicarbonato y carbonato. Los compuestos de carbono orgánico e inorgánico tuvieron una distribución muy heterogénea, los valores de pH (8,24±0,22) y alcalinidad total (2523±119 μmol/kg) indican que el área tiene un comportamiento alcalino, estos montos fueron similares a los encontrados en aguas de la plataforma marina cubanos y superiores a los consignados para el... |
| Tipo: Journal Contribution |
Palavras-chave: Carbon dioxide; Alkalinity; Carbon cycle; Carbon dioxide; Alkalinity; Carbon cycle; Http://aims.fao.org/aos/agrovoc/c_1302; Http://aims.fao.org/aos/agrovoc/c_8721; Http://aims.fao.org/aos/agrovoc/c_17299. |
| Ano: 2009 |
URL: http://hdl.handle.net/1834/3390 |
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| Thevenon, Florian; Williamson, David; Bard, Edouard; Anselmetti, Flavio S.; Beaufort, Luc; Cachier, Helene. |
| This paper addresses the quantification of combustion-derived products in oceanic and continental sediments by optical and chemical approaches, and the interest of combining such methods for reconstructing past biomass burning activity and the pyrogenic carbon cycle. In such context, the dark particles >0.2 mu m(2) remaining after the partial digestion of organic matter are optically counted by automated image analysis and defined as charcoal, while the elemental carbon remaining after thermal and chemical oxidative treatments is quantified as black carbon (BC). The obtained pyrogenic carbon records from three sediment core-based case studies, (i) the Late Pleistocene equatorial Pacific Ocean. (ii) the mid-Holocene European Lake Lucerne, and (iii) the... |
| Tipo: Text |
Palavras-chave: Biomass burning; Carbon cycle; Charcoal; Black carbon; Climate; Human impact. |
| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00231/34198/32764.pdf |
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| 申, 宝明; 佐藤, 禎稔; 岸本, 正; 谷, 昌幸; 仙北谷, 康; 加藤, 拓; 林, 芙俊; SHEN, Baoming; SATOW, Tadatoshi; KISHIMOTO, Tadashi; TANI, Masayuki; SENBOKUYA, Yasushi; KATO, Taku; HAYASHI, Futoshi. |
| マニュアスプレッダによる堆肥の散布精度の現状を把握することを目的とし，横軸ピータ型，縦軸ビータ型，左側方散布型の3機種を対象として堆肥の散布量分布および 堆肥散布精度の調査を行った。各機種の散布量分布は，いずれも山型の形状を示しており，横軸ビータ型，縦軸ピータ型では，マニュアスプレッダの中心から左右1m以内に，それぞれ全体の76%，40%が散布され，左側方散布型は左側3-5mの範囲に全体の71%が集中して散布された。最大散布畳は横軸ビータ型が2.3t/l0a，縦軸ビータ型が6.5t/10a，左側方散布型が10.3t/l0aとなり，重複散布しても規定散布量である2t/l0aが望めない結果となった。また，圃場全体の堆肥散布量は各機種で0.2-3.4t/lOa，2.4-22. 8t/l0a，0.6-5.0t/10aであり， 堆肥の性状によって散布むらが大きくなることが判明した。The purpose of this study was to investigate the present situation of compost spreading with manure spreaders in Tokachi region. Therefore，three different types of manure spreaders: rear horizontal beater type(A)，vertical beater type (B) and side discharge type (C)，were used to determine the application pattern and accuracy of compost spreading. Application pattern of each... |
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Palavras-chave: 堆肥の利用; マッピング; 炭素循環; 精密農法; Utilization of compost; Mapping; Carbon cycle; Precision farming. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2701 |
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| Watson, Andrew J.; Metzl, Nicolas; Schuster, Ute. |
| The oceans are an important sink for anthropogenically produced CO2, and on time scales longer than a century they will be the main repository for the CO2 that humans are emitting. Our knowledge of how ocean uptake varies (regionally and temporally) and the processes that control it is currently observation-limited. Traditionally, and based on sparse observations and models at coarse resolution, ocean uptake has been thought to be relatively invariant. However, in the few places where we have enough observations to define the uptake over periods of many years or decades, it has been found to change substantially at basin scales, responding to indices of climate variability. We illustrate this for three well-studied regions: the equatorial Pacific, the... |
| Tipo: Text |
Palavras-chave: CO2; Carbon cycle; Greenhouse gases; Atmospheric oxygen. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00144/25561/23702.pdf |
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| Lourantou, Anna; Metzl, Nicolas. |
| The fate of the Southern Ocean atmospheric CO(2) sink is under question. Here we assess seasonal to decadal changes of surface fCO(2) within an extended sink area along the track between Kerguelen and Amsterdam islands in the subantarctic zone. Data from 17 oceanographic cruises were used, from 1991 to 2011 and two distinct regions were examined, separated by the Subantarctic Front (SAF). The region south of the SAF displays a strong summer phytoplankton bloom of up to -28 mmol C m(-2) d(-1) within a calm area, constrained by physics and topography. On an annual basis, this region is a 6-fold more important sink than that deduced from Takahashi climatology, highlighting the importance of key-areas separate examination before proceeding to spatial... |
| Tipo: Text |
Palavras-chave: Kerguelen; Air-sea CO2 fluxes; Carbon cycle; Frontal region; Island mass effect; Subantarctic zone. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00144/25557/23706.pdf |
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| Keller, Kathrin M.; Joos, Fortunat; Raible, Christoph C.; Cocco, Valentina; Froelicher, Thomas L.; Dunne, John P.; Gehlen, Marion; Bopp, Laurent; Orr, James C.; Tjiputra, Jerry; Heinze, Christoph; Segschneider, Joachim; Roy, Tilla; Metzl, Nicolas. |
| Climate modes such as the North Atlantic Oscillation (NAO), representing internal variability of the climate system, influence the ocean carbon cycle and may mask trends in the sink of anthropogenic carbon. Here, utilising control runs of six fully coupled Earth System Models, the response of the ocean carbon cycle to the NAO is quantified. The dominating response, a seesaw pattern between the subtropical gyre and the subpolar Northern Atlantic, is instantaneous (<3 months) and dynamically consistent over all models and with observations for a range of physical and biogeochemical variables. All models show asymmetric responses to NAO+ and NAO− forcing, implying non-linearity in the connection between NAO and the ocean carbon cycle. However, model... |
| Tipo: Text |
Palavras-chave: North Atlantic Oscillation; Carbon cycle; Ocean biogeochemistry; Climate modeling; Ocean-atmosphere interaction. |
| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00140/25166/23272.pdf |
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| Dufresne, J-l.; Foujols, M-a.; Denvil, S.; Caubel, A.; Marti, O.; Aumont, Olivier; Balkanski, Y.; Bekki, S.; Bellenger, H.; Benshila, R.; Bony, S.; Bopp, L.; Braconnot, P.; Brockmann, P.; Cadule, P.; Cheruy, F.; Codron, F.; Cozic, A; Cugnet, D.; De Noblet, N.; Duvel, J-p.; Ethe,; Fairhead, L.; Fichefet, T.; Flavoni, S.; Friedlingstein, P.; Grandpeix, J-y.; Guez, L.; Guilyardi, E.; Hauglustaine, D.; Hourdin, F.; Idelkadi, A.; Ghattas, J.; Joussaume, S.; Kageyama, M.; Krinner, G.; Labetoulle, S.; Lahellec, A.; Lefebvre, M; Lefevre, F.; Levy, C.; Li, Zhanbin; Lloyd, J.; Lott, F.; Madec, G.; Mancip, M.; Marchand, M; Masson, S.; Meurdesoif, Y.; Mignot, J.; Musat, I.; Parouty, S.; Polcher, J.; Rio, C; Schulz, M.; Swingedouw, D.; Szopa, S.; Talandier, Claude; Terray, P.; Viovy, N.; Vuichard, N.. |
| We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper... |
| Tipo: Text |
Palavras-chave: Climate; Climate change; Climate projections; Earth System Model; CMIP5; CMIP3; Greenhouse gases; Aerosols; Carbon cycle; Allowable emissions; RCP scenarios; Land use changes. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00138/24966/23079.pdf |
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| Hauck, J.; Voelker, C.; Wang, T.; Hoppema, M.; Losch, M.; Wolf-gladrow, D. A.. |
| Stratospheric ozone depletion and emission of greenhouse gases lead to a trend of the southern annular mode (SAM) toward its high-index polarity. The positive phase of the SAM is characterized by stronger than usual westerly winds that induce changes in the physical carbon transport. Changes in the natural carbon budget of the upper 100 m of the Southern Ocean in response to a positive SAM phase are explored with a coupled ecosystem-general circulation model and regression analysis. Previously overlooked processes that are important for the upper ocean carbon budget during a positive SAM period are identified, namely, export production and downward transport of carbon north of the polar front (PF) as large as the upwelling in the south. The limiting... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Southern annular mode; Carbon cycle; Carbon sink. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00292/40352/38988.pdf |
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| Laruelle, Goulven G.; Lauerwald, Ronny; Pfeil, Benjamin; Regnier, Pierre. |
| Over the past decade, estimates of the atmospheric CO2 uptake by continental shelf seas were constrained within the 0.18-0.45 Pg C yr(-1) range. However, most of those estimates are based on extrapolations from limited data sets of local flux measurements (n<100). Here we propose to derive the CO2 air-sea exchange of the shelf seas by extracting 310(6) direct surface ocean CO2 measurements from the global database SOCAT (Surface Ocean CO2 Atlas), atmospheric CO2 values from GlobalVIEW and calculating gas transfer rates using readily available global temperature, salinity, and wind speed fields. We then aggregate our results using a global segmentation of the shelf in 45 units and 152 subunits to establish a consistent regionalized CO2 exchange budget at... |
| Tipo: Text |
Palavras-chave: CO2; Coastal ocean; Carbon cycle. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00293/40426/38969.pdf |
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| Skinner, Luke C.; Waelbroeck, Claire; Scrivner, Adam E.; Fallon, Stewart J.. |
| Recent theories for glacial-interglacial climate transitions call on millennial climate perturbations that purged the deep sea of sequestered carbon dioxide via a "bipolar ventilation seesaw." However, the viability of this hypothesis has been contested, and robust evidence in its support is lacking. Here we present a record of North Atlantic deep-water radiocarbon ventilation, which we compare with similar data from the Southern Ocean. A striking coherence in ventilation changes is found, with extremely high ventilation ages prevailing across the deep Atlantic during the last glacial period. The data also reveal two reversals in the ventilation gradient between the deep North Atlantic and Southern Ocean during Heinrich Stadial 1 and the Younger Dryas.... |
| Tipo: Text |
Palavras-chave: Ocean circulation; Carbon cycle; Abrupt change. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00290/40153/39327.pdf |
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| Registros recuperados: 36 | |
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