NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Collections About News Help Login
Back to Results
Oxidation and reduction rates for organic carbon in the Amazon mainstream tributary and floodplain, inferred from distributions of dissolved gasesConcentrations of CO2, O2, CH4, and N2O in the Amazon River system reflect an oxidation-reduction sequence in combination with physical mixing between the floodplain and the mainstem. Concentrations of CO2 ranged from 150 microM in the Amazon mainstem to 200 to 300 microM in aerobic waters of the floodplain, and up to 1000 microM in oxygen-depleted environments. Apparent oxygen utilization (AOU) ranged from 80 to 250 microM. Methane was highly supersaturated, with concentrations ranging from 0.06 microM in the mainstem to 100 microM on the floodplain. Concentrations of N2O were slightly supersaturated in the mainstem, but were undersaturated on the floodplain. Fluxes calculated from these concentrations indicated decomposition of 1600 g C sq m y(-1) of organic carbon in Amazon floodplain waters. Analysis of relationships between CH4, O2, and CO2 concentrations indicated that approximately 50 percent of carbon mineralization on the floodplain is anaerobic, with 20 percent lost to the atmoshphere as CH4. The predominance of anaerobic metabolism leads to consumption of N2O on the flood plane. Elevated concentrations of CH4 in the mainstem probably reflect imput from the floodplain, while high levels of CO2 in the mainstem are derived from a combination of varzea drainage and in situ respiration.
Document ID
19880015678
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Richey, Jeffrey E. (Washington Univ. Seattle., United States)
Devol, Allan H. (Washington Univ. Seattle., United States)
Wofsy, Steven C. (Harvard Univ. Cambridge, MA., United States)
Victoria, Reynaldo (Centro de Energia Nuclear na Agricultura Piracicaba (Brazil), United States)
Riberio, Maria N. G. (Instituto Nacional de Pesquisas da Amazonia Manaus, Brazil)
Date Acquired
September 5, 2013
Publication Date
January 1, 1986
Subject Category
Environment Pollution
Report/Patent Number
NAS 1.26:182943
NASA-CR-182943
Accession Number
88N25062
Funding Number(s)
CONTRACT_GRANT: NAGW-711
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Related Records

There are no records associated with this record.
No Preview Available