High Rates of Methane Oxidation in an Amazon Floodplain Lake

TitleHigh Rates of Methane Oxidation in an Amazon Floodplain Lake
Publication TypeJournal Article
Year of Publication2018
AuthorsBarbosa, Pedro M., Farjalla Vinicius F., Melack John M., Amaral Joao H., and Forsberg Bruce R.
JournalBiogeochemistry
Volume137
Number3
Pages351-365
Date Published02/2018
Abstract / Summary

Methane (CH4) oxidation may consume large amounts of dissolved CH4 in lakes and wetlands. Here, we estimated CH4 oxidation rates in an Amazonian floodplain lake during periods representative of the annual variations in water level, using incubations and measurements of δ13C-CH4. A large fraction of the CH4 produced was oxidized (from 34 to ~ 100%, average = 80%), with volumetric CH4 oxidation rates ranging from 1 to 132 mg C m−3 d−1. Heavier values of δ13C-CH4 in surface waters when compared to bottom waters and sediment bubbles corroborates the high CH4 oxidation rates observed. The depth-integrated oxidation rates were of the same magnitude as the calculate CH4 evasion to the atmosphere, which indicates that methane oxidation is an important sink of CH4 and is likely to be important in the many similar lakes encountered in the Amazon River basin.

 

URLhttps://doi.org/10.1007/s10533-018-0425-2
DOI10.1007/s10533-018-0425-2
Journal: Biogeochemistry
Year of Publication: 2018
Volume: 137
Number: 3
Pages: 351-365
Date Published: 02/2018

Methane (CH4) oxidation may consume large amounts of dissolved CH4 in lakes and wetlands. Here, we estimated CH4 oxidation rates in an Amazonian floodplain lake during periods representative of the annual variations in water level, using incubations and measurements of δ13C-CH4. A large fraction of the CH4 produced was oxidized (from 34 to ~ 100%, average = 80%), with volumetric CH4 oxidation rates ranging from 1 to 132 mg C m−3 d−1. Heavier values of δ13C-CH4 in surface waters when compared to bottom waters and sediment bubbles corroborates the high CH4 oxidation rates observed. The depth-integrated oxidation rates were of the same magnitude as the calculate CH4 evasion to the atmosphere, which indicates that methane oxidation is an important sink of CH4 and is likely to be important in the many similar lakes encountered in the Amazon River basin.

 

DOI: 10.1007/s10533-018-0425-2
Citation:
Barbosa, PM, VF Farjalla, JM Melack, JH Amaral, and BR Forsberg.  2018.  "High Rates of Methane Oxidation in an Amazon Floodplain Lake."  Biogeochemistry 137(3): 351-365.  https://doi.org/10.1007/s10533-018-0425-2.