%0 Journal Article
%4 dpi.inpe.br/plutao/2011/11.23.19.40.09
%2 dpi.inpe.br/plutao/2011/11.23.19.40.10
%@doi 10.1029/2011JG001699
%@issn 0148-0227
%@issn 2156-2202
%F lattes: 9857505876280820 5 RudorffMelMacBarNov:2011:SeSpVa
%T Seasonal and spatial variability of CO2 emission from a large floodplain lake in the lower Amazon
%D 2011
%8 Oct.
%9 journal article
%A Rudorff, Conrado de Moraes,
%A Melack, John M.,
%A MacIntyre, Sally,
%A Barbosa, Claudio Clemente Faria,
%A Novo, Evlyn Márcia Leão de Moraes,
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Bren School of Environmental Science and Management, University of California
%@affiliation Marine Science Institute, University of California
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@electronicmailaddress cmr@ltid.inpe.br
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress claudio@dpi.inpe.br
%@electronicmailaddress evlyn@ltid.inpe.br
%B Journal of Geophysical Research
%V 116
%N G04007
%P 1-12
%K carbon-dioxide, methane, river, exchange, waters, budget, Brazil, layer.
%X he inundation status of the Amazon floodplain affects biogenic gas production and evasion. We analyzed spatial variability of dissolved CO(2) concentration and gas evasion in a large floodplain lake in the lower reach of the Amazon River in four hydrological phases. We calculated surficial CO(2) concentrations from measurements of pH, dissolved inorganic carbon, temperature, and conductivity and used meteorological data to calculate gas transfer coefficients to estimate CO(2) evasion. Gas transfer coefficients that take into account both wind and heating and cooling at the lake's surface are on the order of 10 cm hr(-1), approximately four times higher than values previously used in regional estimates of gas evasion from lakes on the Amazon floodplain. Supersaturation of CO(2) occurred throughout the lake and was higher in the littoral zone and in regions receiving Amazon River inflows. CO(2) concentration was reduced in regions with phytoplankton blooms. The range of CO(2) concentrations was least at low water, 47 mu M to 233 mu M, and largest at high water, 1 mu M to 656 mu M; the average annual value was 125 mu M. We estimate mean (+/- standard deviation) fluxes from open-water in L. Curuai to the atmosphere of 44 +/- 15, 348 +/- 13, 371 +/- 23, and 364 +/- 20 mmol CO(2) m(-2) d(-1) during receding, low, rising, and high water, respectively. The error associated with these values reflects, for each hydrological phase, the spatial variation in CO(2) concentration in L. Curuai, a likely range in atmospheric CO(2) levels and temporal variations in gas transfer coefficient within 10-day periods.
%@language en
%3 jgrg836.pdf