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Registro Completo |
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Biblioteca(s): |
Embrapa Pantanal. |
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Data corrente: |
03/01/1996 |
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Data da última atualização: |
04/04/2017 |
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Autoria: |
HAMILTON, S. K.; SIPPEL, S. J.; MELACK, J. M. |
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Título: |
Oxygen depletion and carbon dioxide and methane production in waters of the Pantanal wetland of Brazil. |
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Ano de publicação: |
1995 |
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Fonte/Imprenta: |
Biogeochemistry, v.30, n.2, p.115-141, 1995. |
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Idioma: |
Inglês |
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Conteúdo: |
This study examines dissolved O2, CO2 and CH4 in waters of the Pantanal a vast savanna floodplain. Measurements are presented for 540 samples from throughout the region, ranging from areas of sheet flooding to sluggish marsh strams to the major rivers of the region. Dissolved O2 is often strongly depleted, particularly in waters filed with emergent vascular plants, which are the most extensive aquatic environment of the region. Median O2 concentrations were 35 uM for vegetated waters, 116 uM for the Paraguay River, 95 uM for tributary rivers, and 165 uM for open lakes (atmospheric equilibrium, 230-290 uM). Air-water diffusive fluxes were calculated from dissolved gas concentrations for representative vegetated floodplain waters, based on data collected over the course of an annual cycle. These fluxes reveal about twice as much CO2 evasion as can be accounted for by invasion of O2 (overall means in nmol cm-2s-1:O2 0.18, CO2 0.34 and CH4 0,017). Methanogenesis is estimated to account for ca.20% of the total heterotropic metabolism in the water column and sediments, with the remainder likely due mostly to aerobic respiration. Anaerobic respiration is limited by the low concentrations of alternate electron acceptors. We hypothesize that O2 transported through the stems of emergent plants is consumed in aerobic respiration by plant tissues or microorganisms, producing CO2 that preferentially dissolves into the water and thus explaining most of the excess CO2 evasion. This hyphotesis is supported by measurements of gases in submersed stems of emergent plants. MenosThis study examines dissolved O2, CO2 and CH4 in waters of the Pantanal a vast savanna floodplain. Measurements are presented for 540 samples from throughout the region, ranging from areas of sheet flooding to sluggish marsh strams to the major rivers of the region. Dissolved O2 is often strongly depleted, particularly in waters filed with emergent vascular plants, which are the most extensive aquatic environment of the region. Median O2 concentrations were 35 uM for vegetated waters, 116 uM for the Paraguay River, 95 uM for tributary rivers, and 165 uM for open lakes (atmospheric equilibrium, 230-290 uM). Air-water diffusive fluxes were calculated from dissolved gas concentrations for representative vegetated floodplain waters, based on data collected over the course of an annual cycle. These fluxes reveal about twice as much CO2 evasion as can be accounted for by invasion of O2 (overall means in nmol cm-2s-1:O2 0.18, CO2 0.34 and CH4 0,017). Methanogenesis is estimated to account for ca.20% of the total heterotropic metabolism in the water column and sediments, with the remainder likely due mostly to aerobic respiration. Anaerobic respiration is limited by the low concentrations of alternate electron acceptors. We hypothesize that O2 transported through the stems of emergent plants is consumed in aerobic respiration by plant tissues or microorganisms, producing CO2 that preferentially dissolves into the water and thus explaining most of the excess CO2 evasion. This hyphote... Mostrar Tudo |
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Palavras-Chave: |
Aquatic plant; Decomposition; Sediment. |
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Thesagro: |
Decomposição; Planta Aquatica; Sedimento. |
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Thesaurus Nal: |
floodplains; Pantanal; wetlands. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02264naa a2200253 a 4500
001 1786579
005 2017-04-04
008 1995 bl --- 0-- u #d
100 1 $aHAMILTON, S. K.
245 $aOxygen depletion and carbon dioxide and methane production in waters of the Pantanal wetland of Brazil.
260 $c1995
520 $aThis study examines dissolved O2, CO2 and CH4 in waters of the Pantanal a vast savanna floodplain. Measurements are presented for 540 samples from throughout the region, ranging from areas of sheet flooding to sluggish marsh strams to the major rivers of the region. Dissolved O2 is often strongly depleted, particularly in waters filed with emergent vascular plants, which are the most extensive aquatic environment of the region. Median O2 concentrations were 35 uM for vegetated waters, 116 uM for the Paraguay River, 95 uM for tributary rivers, and 165 uM for open lakes (atmospheric equilibrium, 230-290 uM). Air-water diffusive fluxes were calculated from dissolved gas concentrations for representative vegetated floodplain waters, based on data collected over the course of an annual cycle. These fluxes reveal about twice as much CO2 evasion as can be accounted for by invasion of O2 (overall means in nmol cm-2s-1:O2 0.18, CO2 0.34 and CH4 0,017). Methanogenesis is estimated to account for ca.20% of the total heterotropic metabolism in the water column and sediments, with the remainder likely due mostly to aerobic respiration. Anaerobic respiration is limited by the low concentrations of alternate electron acceptors. We hypothesize that O2 transported through the stems of emergent plants is consumed in aerobic respiration by plant tissues or microorganisms, producing CO2 that preferentially dissolves into the water and thus explaining most of the excess CO2 evasion. This hyphotesis is supported by measurements of gases in submersed stems of emergent plants.
650 $afloodplains
650 $aPantanal
650 $awetlands
650 $aDecomposição
650 $aPlanta Aquatica
650 $aSedimento
653 $aAquatic plant
653 $aDecomposition
653 $aSediment
700 1 $aSIPPEL, S. J.
700 1 $aMELACK, J. M.
773 $tBiogeochemistry$gv.30, n.2, p.115-141, 1995.
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Registro original: |
Embrapa Pantanal (CPAP) |
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| Registros recuperados : 8 | |
| 7. |  | MALHI, Y.; MELACK, J.; GATTI, L. V.; OMETTO, J.; KESSELMEIER, J.; WOLFF, S.; ARAGÃO, L. E. O.; COSTA, M.; SALESKA, S.; PANGALA, S. R.; BASSO, L. S.; RIZZO, L.; ARAUJO, A. C. de; RESTREPO-COUPE, N. Biogeochemical cycles of the Amazon. In: SCIENCE panel for the Amazon: Amazon assessment report 2021: part I: The Amazon as a regional entity of the Earth system. New York, NY: United Nations Sustainable Development Solutions Network, 2021. Cap. 6, pag. irregular.| Tipo: Capítulo em Livro Técnico-Científico |
| Biblioteca(s): Embrapa Amazônia Oriental. |
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| 8. | | NOVO, E. M. L. de; FERREIRA, L. G.; BARBOSA, C.; CARVALHO, C.; SANO, E. E.; SHIMABUKURO, Y.; HUETE, A.; POTTER, C.; ROBERTS, Dar A.; HESS, L. L.; MELACK, J. J.; YOSHIOKA, H.; KLOOSTER, S.; KUMAR, V.; MYNENI, R.; RATANA, P.; DIDAN, K.; MIURA, T. Técnicas avançadas de sensoriamento remoto aplicadas ao estudo de mudanças climáticas e ao funcionamento dos ecossistemas amazônicos. Acta Amazonica, Manaus, v. 35, n. 2, p. 259-272, abr./jun. 2005.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: Nacional - A |
| Biblioteca(s): Embrapa Amazônia Oriental. |
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| Registros recuperados : 8 | |
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| Nenhum registro encontrado para a expressão de busca informada. |
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