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Title: Combining eddy-covariance and chamber measurements to determine the methane budget from a small, heterogeneous urban floodplain wetland park

Abstract

Methane (CH 4) emissions and carbon uptake in temperate freshwater wetlands act in opposing directions in the context of global radiative forcing. Large uncertainties exist for the rates of CH 4 emissions making it difficult to determine the extent that CH 4 emissions counteract the carbon sequestration of wetlands. Urban temperate wetlands are typically small and feature highly heterogeneous land cover, posing an additional challenge to determining their CH 4 budget. The data analysis approach we introduce here combines two different CH 4 flux measurement techniques to overcome scale and heterogeneity problems and determine the overall CH 4 budget of a small, heterogeneous, urban wetland landscape. Temporally intermittent point measurements from non-steady-state chambers provided information about patch-level heterogeneity of fluxes, while continuous, high temporal resolution flux measurements using the eddy-covariance (EC) technique provided information about the temporal dynamics of the fluxes. Patch-level scaling parameterization was developed from the chamber data to scale eddy covariance data to a ‘fixed-frame’, which corrects for variability in the spatial coverage of the eddy covariance observation footprint at any single point in time. Finally, by combining two measurement techniques at different scales, we addressed shortcomings of both techniques with respect to heterogeneous wetland sites.

Authors:
 [1];  [1];  [2];  [1];  [1];  [3]
  1. The Ohio State Univ., Columbus, OH (United States). Dept. of Civil and Environmental Engineering and Geodetic Science
  2. The Ohio State Univ., Columbus, OH (United States). Dept. of Civil and Environmental Engineering and Geodetic Science; The Ohio State Univ., Columbus, OH (United States). School of Environment and Natural Resources
  3. The Ohio State Univ., Columbus, OH (United States). School of Environment and Natural Resources; Florida Gulf Coast Univ., Naples, FL (United States). Everglades Wetland Research Park
Publication Date:
Research Org.:
The Ohio State Univ., Columbus, OH (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC)
OSTI Identifier:
1418523
Alternate Identifier(s):
OSTI ID: 1419522
Grant/Contract Number:
G11AP20099; 1508994; 1033451; 1601224; 7079856
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Agricultural and Forest Meteorology
Additional Journal Information:
Journal Volume: 237-238; Journal Issue: C; Journal ID: ISSN 0168-1923
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; 54 ENVIRONMENTAL SCIENCES; CH4; Land-surface heterogeneity; Surface-atmosphere interactions; Eddy covariance; footprint model; Olentangy River Wetland Research Park

Citation Formats

Morin, T. H., Bohrer, G., Stefanik, K. C., Rey-Sanchez, A. C., Matheny, A. M., and Mitsch, W. J.. Combining eddy-covariance and chamber measurements to determine the methane budget from a small, heterogeneous urban floodplain wetland park. United States: N. p., 2017. Web. doi:10.1016/j.agrformet.2017.01.022.
Morin, T. H., Bohrer, G., Stefanik, K. C., Rey-Sanchez, A. C., Matheny, A. M., & Mitsch, W. J.. Combining eddy-covariance and chamber measurements to determine the methane budget from a small, heterogeneous urban floodplain wetland park. United States. doi:10.1016/j.agrformet.2017.01.022.
Morin, T. H., Bohrer, G., Stefanik, K. C., Rey-Sanchez, A. C., Matheny, A. M., and Mitsch, W. J.. Fri . "Combining eddy-covariance and chamber measurements to determine the methane budget from a small, heterogeneous urban floodplain wetland park". United States. doi:10.1016/j.agrformet.2017.01.022. https://www.osti.gov/servlets/purl/1418523.
@article{osti_1418523,
title = {Combining eddy-covariance and chamber measurements to determine the methane budget from a small, heterogeneous urban floodplain wetland park},
author = {Morin, T. H. and Bohrer, G. and Stefanik, K. C. and Rey-Sanchez, A. C. and Matheny, A. M. and Mitsch, W. J.},
abstractNote = {Methane (CH4) emissions and carbon uptake in temperate freshwater wetlands act in opposing directions in the context of global radiative forcing. Large uncertainties exist for the rates of CH4 emissions making it difficult to determine the extent that CH4 emissions counteract the carbon sequestration of wetlands. Urban temperate wetlands are typically small and feature highly heterogeneous land cover, posing an additional challenge to determining their CH4 budget. The data analysis approach we introduce here combines two different CH4 flux measurement techniques to overcome scale and heterogeneity problems and determine the overall CH4 budget of a small, heterogeneous, urban wetland landscape. Temporally intermittent point measurements from non-steady-state chambers provided information about patch-level heterogeneity of fluxes, while continuous, high temporal resolution flux measurements using the eddy-covariance (EC) technique provided information about the temporal dynamics of the fluxes. Patch-level scaling parameterization was developed from the chamber data to scale eddy covariance data to a ‘fixed-frame’, which corrects for variability in the spatial coverage of the eddy covariance observation footprint at any single point in time. Finally, by combining two measurement techniques at different scales, we addressed shortcomings of both techniques with respect to heterogeneous wetland sites.},
doi = {10.1016/j.agrformet.2017.01.022},
journal = {Agricultural and Forest Meteorology},
number = C,
volume = 237-238,
place = {United States},
year = {Fri Feb 17 00:00:00 EST 2017},
month = {Fri Feb 17 00:00:00 EST 2017}
}

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