HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Chan, A. S. K. Articles by Parkin, T. B. Search for Related Content PubMed Articles by Chan, A. S. K. Articles by Parkin, T. B. Agricola Articles by Chan, A. S. K. Articles by Parkin, T. B.

Comparison of Closed-Chamber and Bowen-Ratio Methods for Determining Methane Flux from Peatland Surfaces

Department of Microbiology, Immunology and Preventive Medicine, Iowa State University, Ames, IA 50011; and U.S. Department of Agriculture, Agricultural Research Service, National Soil Tilth Laboratory, 2150 Pammel Drive, Ames, IA 50011.

^* Corresponding author (parkin{at}nstl.gov).

ABSTRACT

Methane (CH₄) is an important greenhouse gas, and it has been estimated that 50% of annual CH₄ comes from terrestrial systems. Better and more accurate methods are needed to quantify CH₄ flux from terrestrial environments. Two general methods commonly applied to measure trace gas fluxes are soil cover (chamber) techniques, and micrometeorology methods. Both of these methods has advantages and disadvantages, yet little information is available concerning the relative performance of the techniques. This study was conducted to compare CH₄ flux measurements obtained by using a closed-chamber soil cover technique and a micrometeorological method (Bowen-ratio Energy Balance [BREB]). Methane flux rates obtained by both methods were compared using nine time points over 3 d at a peatland site in north central Minnesota. Mean CH₄ fluxes obtained by both methods were of the same magnitude (2.43–5.88 mg CH₄ m^–2 h^–1); however, differences were observed in the magnitudes of temporal variability as well as the detection sensitivities (minimum detectable flux). The minimum detectable flux for the closed-chamber method was 9.32 x 10^–2 mg CH₄ m^–2 h^–1, while the minimum detectable flux for the BREB method ranged from 2.16 to 25.5 mg CH₄ m^–2 h^–1. Due to analytical uncertainties associated with gas chromatographic determination of CH₄ gradients, the BREB is not recommended.

This article has been cited by other articles:

				A.S.K. Chan and T.B. Parkin Methane Oxidation and Production Activity in Soils from Natural and Agricultural Ecosystems J. Environ. Qual., November 1, 2001; 30(6): 1896 - 1903. [Abstract] [Full Text] [PDF]

				A.S.K. Chan and T.B. Parkin Effect of Land Use on Methane Flux from Soil J. Environ. Qual., May 1, 2001; 30(3): 786 - 797. [Abstract] [Full Text] [PDF]

				J.A. Zahn, J.L. Hatfield, D.A. Laird, T.T. Hart, Y.S. Do, and A.A. DiSpirito Functional Classification of Swine Manure Management Systems Based on Effluent and Gas Emission Characteristics J. Environ. Qual., March 1, 2001; 30(2): 635 - 647. [Abstract] [Full Text] [PDF]