Processes Controlling Methane Emissions From a Tropical Peatland Drainage Canal
Name
JGR Biogeosciences - 2023 - Somers - Processes Controlling Methane Emissions From a Tropical Peatland Drainage Canal.pdf
Description
Published version
Size
2.63 MB
Format
Adobe PDF
Checksum (MD5)
74ff39513e30cf65885a8dee2c57fad0
Author(s)
Somers, Lauren D
Hoyt, Alison
Cobb, Alexander R
Isnin, Suhailah
Suhip, Muhammad Asri Akmal bin Haji
Sukri, Rahayu S
Gandois, Laure
Harvey, Charles
Date Issued
February 5, 2023
Journal
Journal of Geophysical Research: Biogeosciences
Publisher
American Geophysical Union
Citation
Somers, L. D., Hoyt, A., Cobb, A. R., Isnin, S., Suhip, M. A. A. b. H., Sukri, R. S., et al. (2023). Processes controlling methane emissions from a tropical peatland drainage canal. Journal of Geophysical Research: Biogeosciences, 128, e2022JG007194.
Version
Final published version
Abstract
Most peat domes in Southeast Asia are crisscrossed by networks of drainage canals. These canals are a potentially important source of methane to the atmosphere because the groundwater that discharges into them carries high concentrations of dissolved methane that is produced within peat. In this study, we present an isotope‐enabled numerical model that simulates transport, degassing, and oxidation of methane and dissolved inorganic carbon (DIC) along a drainage canal. We then estimate methane fluxes through a 5‐km canal that crosses a disturbed, forested, but undeveloped, peat dome in Brunei Darussalam by applying this model to field data: concentrations and stable carbon isotopic ratios of both methane and dissolved inorganic carbon from both peat porewater and canal water. We estimate that approximately 70% of the methane entering the canal is oxidized within the canal, 26% is degassed to the atmosphere, and 4% is transported toward the ocean, under low to moderate flow conditions. The flux of methane to the atmosphere is lowest at the maximum elevation of the canal, where flow is stagnant and methane concentrations are highest. Downstream, as flow velocity increases, methane emissions plateau even as methane concentrations decrease. The resulting methane emissions from the canal are large compared to emissions from the peat surface and vegetation on a per‐area basis. However, since the canal covers only a small portion of the catchment area, the canal may be a substantial but not dominant source of methane from the peatland.
MIT Department
Massachusetts Institute of Technology. Department of Civil and Environmental Engineering
Singapore-MIT Alliance in Research and Technology (SMART)
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
10.1029/2022jg007194
