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Dataset Abstract Trace gases (nitrous oxide, methane, and carbon dioxide) have been measured on the LTER Main Site since 1991 and on Successional and Forest sites since 1993. Trace gas fluxes are measured twice monthly or monthly until the ground freezes using permanently-installed, in-situ static chambers. CH4 and N2O are analyzed with gas-chromatography and CO2 with an infrared gas analyzer. Soil moisture and temperature are measured during sampling. original data source http://lter.kbs.msu.edu/datasets/16
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Trace gas fluxes from tidal salt marsh soils: implications for carbon–sulfur biogeochemistry
Abstract. Tidal salt marsh soils can be a dynamic source of greenhouse gases such ascarbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O),as well as sulfur-based trace gases such as carbon disulfide (CS2) anddimethylsulfide (DMS) which play roles in global climate and carbon–sulfurbiogeochemistry. Due to the difficulty in measuring trace gases in coastalecosystems (e.g., flooding, salinity), our current understanding is based onsnapshot instantaneous measurements (e.g., performed during daytime lowtide) which complicates our ability to assess the role of these ecosystemsfor natural climate solutions. We performed continuous, automatedmeasurements of soil trace gas fluxes throughout the growing season toobtain high-temporal frequency data and to provide insights into magnitudesand temporal variability across rapidly changing conditions such as tidalcycles. We found that soil CO2 fluxes did not show a consistent dielpattern, CH4, N2O, and CS2 fluxes were highly variable withfrequent pulse emissions (> 2500 %, > 10 000 %,and > 4500 % change, respectively), and DMS fluxes onlyoccurred midday with changes > 185 000 %. When we comparedcontinuous measurements with discrete temporal measurements (during daytime,at low tide), discrete measurements of soil CO2 fluxes were comparablewith those from continuous measurements but misrepresent the temporalvariability and magnitudes of CH4, N2O, DMS, and CS2.Discrepancies between the continuous and discrete measurement data result indifferences for calculating the sustained global warming potential (SGWP),mainly by an overestimation of CH4 fluxes when using discretemeasurements. The high temporal variability of trace gas fluxes complicatesthe accurate calculation of budgets for use in blue carbon accounting andearth system models.
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- Award ID(s):
- 1652594
- PAR ID:
- 10395719
- Date Published:
- Journal Name:
- Biogeosciences
- Volume:
- 19
- Issue:
- 19
- ISSN:
- 1726-4189
- Page Range / eLocation ID:
- 4655 to 4670
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/bg-19-4655-2022
