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Registro Completo |
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Biblioteca(s): |
Embrapa Pantanal. |
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Data corrente: |
03/10/2005 |
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Data da última atualização: |
10/03/2017 |
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Autoria: |
DEVOL. A. H.; FORSBERG, B. R.; RICHEY, J, E.; PIMENTEL, T. P. |
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Título: |
Seasonal variation in chemical distributions in the Amazon (Solimões) river: a multiyear time series. |
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Ano de publicação: |
1995 |
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Fonte/Imprenta: |
Global Biogeochemical Cycle, v. 9, n. 3, p. 307-328, 1995. |
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Idioma: |
Inglês |
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Conteúdo: |
The results of a 10-year time series study of the chemistry of the Amazon River mainstem near Manaus, Brazil, are presented. All variable measured showed distinct seasonal patterns linked to the discharge hydrograph except respiration rate and PO³4 concentation. Stepwise multiple regression analysis showed that alkalinity, calcium, fine suspended sediment, and sulfate were correlated, primarily, with the percentage of the total water discharge that was derived from Andean drainages. Silicate, potassium, and the weight percentages of carbon and nitrogen in the coarse suspended sediment were correlated with the precentage of water attributable to local lowland drainages. These correlations suggest that seasonal cycles of these variables were particulate carbon, nitrongen, and phosphorus species were controlled by river surface slope, suggesting that the seasonal cycles of these variables were controlled by river turbulence. The biogeochemically active elements O2, CO2, NO3, and SO=4, along with pH, Na, and C1 were all highly correlated with river discharge. The shaoes of the seasonal cycles of O2 and CO2 and much of their amplitude could be reproduced by a quasi steady state model in which respiration was balanced by air-water gas exchange. In the model, increases in river depth during annual cycle result in increased depth-integrated respiration rates. This produces a drawdown of O2 concentration, which increases air-water gas exchange, until the two processes are in balance. Thus the model produces seasonal cycles in which minimum dissolved O2 and maximum dissolved CO2 coencide with high water and the converse at low water, in agreement with the observations. The remainder of the amplitude signal was probably either advected in from upstream or produced by lateral exchange with the fringing floodplain. MenosThe results of a 10-year time series study of the chemistry of the Amazon River mainstem near Manaus, Brazil, are presented. All variable measured showed distinct seasonal patterns linked to the discharge hydrograph except respiration rate and PO³4 concentation. Stepwise multiple regression analysis showed that alkalinity, calcium, fine suspended sediment, and sulfate were correlated, primarily, with the percentage of the total water discharge that was derived from Andean drainages. Silicate, potassium, and the weight percentages of carbon and nitrogen in the coarse suspended sediment were correlated with the precentage of water attributable to local lowland drainages. These correlations suggest that seasonal cycles of these variables were particulate carbon, nitrongen, and phosphorus species were controlled by river surface slope, suggesting that the seasonal cycles of these variables were controlled by river turbulence. The biogeochemically active elements O2, CO2, NO3, and SO=4, along with pH, Na, and C1 were all highly correlated with river discharge. The shaoes of the seasonal cycles of O2 and CO2 and much of their amplitude could be reproduced by a quasi steady state model in which respiration was balanced by air-water gas exchange. In the model, increases in river depth during annual cycle result in increased depth-integrated respiration rates. This produces a drawdown of O2 concentration, which increases air-water gas exchange, until the two processes are in balance.... Mostrar Tudo |
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Palavras-Chave: |
Brasil; Hidrograph; Rio Amazonas. |
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Thesagro: |
Hidrografia; Variação Sazonal. |
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Thesaurus Nal: |
Amazon River; Brazil; seasonal variation. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02540naa a2200253 a 4500
001 1802452
005 2017-03-10
008 1995 bl --- 0-- u #d
100 1 $aDEVOL. A. H.
245 $aSeasonal variation in chemical distributions in the Amazon (Solimões) river$ba multiyear time series.
260 $c1995
520 $aThe results of a 10-year time series study of the chemistry of the Amazon River mainstem near Manaus, Brazil, are presented. All variable measured showed distinct seasonal patterns linked to the discharge hydrograph except respiration rate and PO³4 concentation. Stepwise multiple regression analysis showed that alkalinity, calcium, fine suspended sediment, and sulfate were correlated, primarily, with the percentage of the total water discharge that was derived from Andean drainages. Silicate, potassium, and the weight percentages of carbon and nitrogen in the coarse suspended sediment were correlated with the precentage of water attributable to local lowland drainages. These correlations suggest that seasonal cycles of these variables were particulate carbon, nitrongen, and phosphorus species were controlled by river surface slope, suggesting that the seasonal cycles of these variables were controlled by river turbulence. The biogeochemically active elements O2, CO2, NO3, and SO=4, along with pH, Na, and C1 were all highly correlated with river discharge. The shaoes of the seasonal cycles of O2 and CO2 and much of their amplitude could be reproduced by a quasi steady state model in which respiration was balanced by air-water gas exchange. In the model, increases in river depth during annual cycle result in increased depth-integrated respiration rates. This produces a drawdown of O2 concentration, which increases air-water gas exchange, until the two processes are in balance. Thus the model produces seasonal cycles in which minimum dissolved O2 and maximum dissolved CO2 coencide with high water and the converse at low water, in agreement with the observations. The remainder of the amplitude signal was probably either advected in from upstream or produced by lateral exchange with the fringing floodplain.
650 $aAmazon River
650 $aBrazil
650 $aseasonal variation
650 $aHidrografia
650 $aVariação Sazonal
653 $aBrasil
653 $aHidrograph
653 $aRio Amazonas
700 1 $aFORSBERG, B. R.
700 1 $aRICHEY, J, E.
700 1 $aPIMENTEL, T. P.
773 $tGlobal Biogeochemical Cycle$gv. 9, n. 3, p. 307-328, 1995.
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Registro original: |
Embrapa Pantanal (CPAP) |
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| Registros recuperados : 2 | |
| 1. |  | MARKEWITZ, D.; FIGUEIREDO, R. D.; MELAC, J. M.; NOVO, E.; RICHEY, J. E.; RICHEY, J. River corridors of the Amazon Basin and their response to Anthropogenic Change: A look back and a glimpse forward. In: MEETING OF THE AMERICAN, 2010, Foz do Iguaçu. Meeting of the Americas Abstracts... Washington, US: American Geophysical Union, 2010. Não paginado. U41B-04.| Tipo: Resumo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Oriental. |
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| 2. | | VICTORIA, D. de C.; BALLESTER, V.; RICHEY, J. E.; PEREIRA, A. R.; SANTIAGO, A. V. Hydrologic simulation of amazon basins using the Variable Infiltration Capacity model (VIC) In: THE MEETING OF THE AMERICAS, 1., 2010, Foz do Iguaçu. Anais... Washington, DC: AGU Meetings, 2010.| Tipo: Resumo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Oriental; Embrapa Territorial. |
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| Registros recuperados : 2 | |
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| Nenhum registro encontrado para a expressão de busca informada. |
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