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| Registros recuperados: 75 | |
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| Walker, Brian; CSIRO Sustainable Ecosystems; Brian.Walker@csiro.au; Steffen, Will; ; Will.Steffen@dwe.csiro.au. |
| Global change is the net effect of individual and interactive effects of changes in land use, atmospheric composition, biological diversity, and climate. A synthesis of the past six years' activities of the Global Change and Terrestrial Ecosystems project of the IGBP (International Geosphere-Biosphere Programme) deals with global change effects as ecosystem responses and living with global change. Ecosystem responses are considered in terms of changes in function and vegetation composition/structure. Field experiments of elevated CO2 effects on aboveground biomass show, on average, a positive effect on biomass, ranging from -20% to +80%. Some early predictions of CO2 effects (C3 vs. C4 plants, N-fixers, C:N in litter) are not generally supported, and it... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Agriculture; Biomes; Carbon dioxide; Climate; Dynamics; Ecosystem functioning; Global change; Impacts; Land use; Terrestrial biosphere; Vegetation changes.. |
| Ano: 1997 |
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| Teixeira,Luis G; Fukuda,Adrian; Panosso,Alan R; Lopes,Afonso; Scala Jr,Newton La. |
| Soil tillage is a process that accelerates soil organic matter decomposition transferring carbon to atmosphere, mainly in the CO2 form. In this study, the effect of rotary tillage on soil CO2 emission was investigated, including the presence of crop residues on the surface.Emissions were evaluated during 15 days after tillage in 3 plots: 1) non-tilled and without crop residues on soil surface (NTwo), 2) rotary tiller without the presence of crop residues on soil surface (RTwo), and 3) rotary tiller with the presence of crop residues in soil surface (RTw). Emissions from the RTw plot were higher than the other plots, (0.777 g CO2 m-2 h-1), with the lowest emissions recorded in the NTwo plot (0.414 g CO2 m-2 h-1). Total emission indicates that the difference... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil respiration; Soil tillage; Carbon dioxide; Temporal variability of soil CO2 emission. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162011000600005 |
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| ROGERIO, M. C. P.; BORGES, I.; FERREIRA, A. L.; MACHADO, F. S.; POMPEU, R. C. F. F.; GUEDES, L. F.; COSTA, C. dos S.; GUEDES, F. L.; GALVANI, D. B.. |
| Resumo: A respirometria em ensaios com pequenos ruminantes contribui para a mensuração das emissões de gases de efeito estufa (GEE), subsídio ao pagamento por serviços ambientais e para o desenvolvimento de rações e suplementos que propiciem a máxima eficiência alimentar. Para as aferições de emissão de GEE, 15 cordeiras Santa Inês, com peso de 15,09 kg±2,63 kg, foram avaliadas na câmara respirométrica do Laboratório de Respirometria do Semiárido (Laresa) da Embrapa Caprinos e Ovinos. As dietas foram for-muladas conforme as exigências nutricionais descritas pelo NRC (National Research Council, 2007), em planos nutricionais para manutenção, acaba-mento de carcaça precoce e de carcaça tardia, com cinco repetições. As taxas médias de recuperação para CO2 e... |
| Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Gás carbônico; Energia líquida; Semiárido; Metabolismo nutricional; Caloric increment; Liquid energy; Caprino; Ovino; Incremento Calórico; Metano; Goats; Sheep; Carbon dioxide; Methane; Brazil. |
| Ano: 2019 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1117071 |
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| ARAUJO FILHO, J. C. de; MARQUES, F. A.; AMARAL, A. J. do; CUNHA, T. J. F.; SOUZA JÚNIOR, V. S. de; GALVÃO, P. V. M.. |
| O objetivo deste capítulo é apresentar uma estimativa global do estoque de COS da região semiárida brasileira, considerando os diversos tipos de solos e seus domínios nessa região. Ressalta-se que estimativas dessa magnitude são difíceis de se obter, por vários motivos: a) conhecimento limitado sobre a extensão dos solos (estados mapeados com escalas diferentes e generalizadas); b) escassez de da dos precisos sobre os solos (densidade do solo, profundidade efetiva; frações grossas); c) variação espacial e em profundidade dos valores de COS, densidade e frações grossas em solos de mesma classe; e d) elevada dinâmica do uso e cobertura das terras. A seguir descrevem-se, resumidamente, os principais solos e depois é apresentada a estimativa global do estoque... |
| Tipo: Parte de livro |
Palavras-chave: Bioma Caatinga; Semiárido; Características químicas; Características gerais dos solos; Características físicas; Características mineralógicas; Características morfológicas; Estoque de carbono; Carbono orgânico; Carbono inorgânico; Solo; Dióxido de Carbono; Cobertura Vegetal; Meio Ambiente; Soil; Carbon dioxide; Environment. |
| Ano: 2022 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1150132 |
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| FERNANDES, A. H. B. M.; CARDOSO, M. A.; SOUZA, R. A. C. de; FERNANDES, F. A.; SOARES, M. T. S.; CRISPIM, S. M. A.; GALVANI, F.; LISITA, F. O.. |
| O objetivo deste estudo foi estimar, em condições de laboratório, as taxas de nitrificação e a mineralização de carbono (C) no solo após a aplicação de diferentes doses de dejetos de suínos tratados em biorreatores anaeróbicos. The aim of this work was to evaluate the net nitrification and the C mineralization rates from pig slurry treated in bioreactors and applied to the soil at different doses. |
| Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: CO2; NO3-; Nitrate.; Dióxido de Carbono; Nitrato; Suinocultura.; Carbon dioxide; Swine.. |
| Ano: 2011 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/920832 |
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| Laruelle, Goulven G.; Marescaux, Audrey; Le Gendre, Romain; Garnier, Josette; Rabouille, Christophe; Thieu, Vincent. |
| The Seine river discharges over 700 Gg of carbon (C) every year into the sea mostly under the form of dissolved inorganic carbon (DIC) and emits 445 Gg under the form of carbon dioxide (CO2) to the atmosphere over its entire river network. The watershed, which drains 76,000 km2, is heavily populated with 18 106 inhabitants and is thus submitted to large anthropic pressure. The offline coupling of two Reactive Transport Models is used to understand the complex spatial and temporal dynamics of carbon, oxygen and nutrients and quantify the CO2 exchange at the air-water interface along the main axis of the river. The estuarine section of the Seine is simulated by the generic estuarine model C-GEM (for Carbon Generic Estuarine Model), while the upstream part of... |
| Tipo: Text |
Palavras-chave: Dissolved inorganic and organic carbon; Carbon dioxide; Reactive-transport model; Seine river and estuary; Biogeochemical budget. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00493/60421/63858.pdf |
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| Parard, Gaelle; Boutin, J.; Cuypers, Y.; Bouruet-aubertot, P.; Caniaux, G.. |
| The availability of nutrients in the mixed layer is the main limitation to organic carbon biological production in the tropical regions. In this paper, we investigate the potential role of internal waves at promoting the development of biological activity on a PIRATA mooring at 6 degrees S, 10 degrees W. This mooring is located above the Mid-Atlantic Ridge where we observe strong internal waves. Using a one-dimensional physical and biogeochemical coupled model, we simulate dissolved inorganic carbon (DIC). Providing the influence of vertical advection and turbulent diapycnal diffusivity are (it is vertical advection + turbulent dipycnal mixing) accounted for, we find that this model provides a good fit with observed in situ CO2 fugacity (fCO(2)). Main... |
| Tipo: Text |
Palavras-chave: Carbon dioxide; Internal wave; High frequency; PIRATA; Atlantic tropical; Nitrate flux. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00624/73568/73005.pdf |
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| Takao, Shintaro; Nakaoka, Shin-ichiro; Hashihama, Fuminori; Shimada, Keishi; Yoshikawa-inoue, Hisayuki; Hirawake, Toru; Kanda, Jota; Hashida, Gen; Suzuki, Koji. |
| The Southern Ocean is a vast net sink for atmospheric carbon dioxide (CO2), with marine phytoplankton playing a crucial role in CO2 fixation. We assessed how changes in the dominant phytoplankton community and net primary productivity (NPP) affected variations in the partial pressure of CO2 in surface water (pCO(2)(sw)) in the Indian sector of the Southern Ocean during austral summer. pCO2sw was negatively correlated with total phytoplankton and diatom abundances, as estimated from pigment signatures, in the zone south of the Antarctic Circumpolar Current; however, pCO(2)(sw) was not correlated with haptophyte abundance. Additionally, a stronger correlation was found between pCO(2)(sw) and total phytoplankton NPP than between chlorophyll a concentration... |
| Tipo: Text |
Palavras-chave: Phytoplankton community composition; Diatoms; Southern Ocean; Net primary productivity; Carbon dioxide. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00676/78836/81084.pdf |
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| Lauderdale, Jonathan M.; Dutkiewicz, Stephanie; Williams, Richard G.; Follows, Michael J.. |
| A mechanistic framework for quantitatively mapping the regional drivers of air-sea CO2 fluxes at a global scale is developed. The framework evaluates the interplay between (1) surface heat and freshwater fluxes that influence the potential saturated carbon concentration, which depends on changes in sea surface temperature, salinity and alkalinity, (2) a residual, disequilibrium flux influenced by upwelling and entrainment of remineralized carbon- and nutrient-rich waters from the ocean interior, as well as rapid subduction of surface waters, (3) carbon uptake and export by biological activity as both soft tissue and carbonate, and (4) the effect on surface carbon concentrations due to freshwater precipitation or evaporation. In a steady state simulation of... |
| Tipo: Text |
Palavras-chave: Air-sea flux; Carbon dioxide; Regional drivers. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00383/49416/49873.pdf |
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| Wanninkhof, Rik; Pickers, Penelope A.; Omar, Abdirahman M.; Sutton, Adrienne; Murata, Akihiko; Olsen, Are; Stephens, Britton B.; Tilbrook, Bronte; Munro, David; Pierrot, Denis; Rehder, Gregor; Magdalena Santana-casiano, J.; Mueller, Jens D.; Trinanes, Joaquin; Tedesco, Kathy; O'Brien, Kevin; Currie, Kim; Barberols, Leticia; Telszewski, Maciej; Hoppema, Mario; Ishii, Masao; Gonzalez-davila, Melchor; Bates, Nicholas R.; Metzl, Nicolas; Suntharalingam, Parvadha; Feely, Richard A.; Nakaoka, Shin-ichiro; Lauvset, Siv K.; Takahashi, Taro; Steinhoff, Tobias; Schuster, Ute. |
| The Surface Ocean CO2 NETwork (SOCONET) and atmospheric Marine Boundary Layer (MBL) CO2 measurements from ships and buoys focus on the operational aspects of measurements of CO2 in both the ocean surface and atmospheric MBLs. The goal is to provide accurate pCO(2) data to within 2 micro atmosphere (mu atm) for surface ocean and 0.2 parts per million (ppm) for MBL measurements following rigorous best practices, calibration and intercomparison procedures. Platforms and data will be tracked in near real-time and final quality-controlled data will be provided to the community within a year. The network, involving partners worldwide, will aid in production of important products such as maps of monthly resolved surface ocean CO2 and air-sea CO2 flux... |
| Tipo: Text |
Palavras-chave: Carbon dioxide; Network; Oceanography; Fluxes; Best practices. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00675/78725/80992.pdf |
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| Devries, Tim; Le Quere, Corinne; Andrews, Oliver; Berthet, Sarah; Hauck, Judith; Ilyina, Tatiana; Landschuetzer, Peter; Lenton, Andrew; Lima, Ivan D.; Nowicki, Michael; Schwinger, Jorg; Seferian, Roland. |
| Measurements show large decadal variability in the rate of CO2 accumulation in the atmosphere that is not driven by CO2 emissions. The decade of the 1990s experienced enhanced carbon accumulation in the atmosphere relative to emissions, while in the 2000s, the atmospheric growth rate slowed, even though emissions grew rapidly. These variations are driven by natural sources and sinks of CO2 due to the ocean and the terrestrial biosphere. In this study, we compare three independent methods for estimating oceanic CO2 uptake and find that the ocean carbon sink could be responsible for up to 40% of the observed decadal variability in atmospheric CO2 accumulation. Data-based estimates of the ocean carbon sink from pCO(2) mapping methods and decadal ocean inverse... |
| Tipo: Text |
Palavras-chave: Carbon dioxide; Ocean carbon sink; Terrestrial carbon sink; Climate variability; Carbon budget. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00675/78728/80983.pdf |
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| Registros recuperados: 75 | |
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