TITLE:
Chamber Size Effects on Methane Emissions from Rice Production
AUTHORS:
Alden D. Smartt, Kristofor R. Brye, Christopher W. Rogers, Richard J. Norman, Edward E. Gbur, Jarrod T. Hardke, Trent L. Roberts
KEYWORDS:
Methane Emissions, Rice Production, Clay Soil, Arkansas
JOURNAL NAME:
Open Journal of Soil Science,
Vol.5 No.10,
October
19,
2015
ABSTRACT: Quantifying
methane (CH4) emissions from cultivated rice (Oryza sativa L.) production in the field has received increased
attention recently due to methane’s importance as a greenhouse gas. The
enclosed-headspace chamber technique is the standard methodology for field
assessments of trace gas emissions. However, to our knowledge, no direct
comparisons of measured CH4 fluxes and emissions from field-grown
rice among differing chamber sizes have been reported. Therefore, the objective
of this study was to evaluate the effect of chamber size [15.2- and 30.4-cm
inside diameter (id)] on CH4 fluxes and season-long emissions from
rice grown on a clay soil in Arkansas. Chamber size did not affect (P > 0.05) CH4 fluxes on 10
sampling dates during the flooded portion of the rice growing season and only
affected fluxes on one of four sampling dates after flood release. Total
season-long CH4 emissions from optimally N-fertilized rice were 32.6
and 35.6 kg CH4-C haǃ·seasonǃ, which did not
differ, and from bare clay soil were 0.74 and 1.75 kg CH4-C haǃ·seasonǃ,
which also did not differ, from the 15.2- and 30.4-cm chambers, respectively.
Chamber size (i.e., 15.2- or 30.4-cm
id) did not result in differences in cumulative CH4 emissions from
this flooded-rice study that was conducted on a Sharkey clay soil in northeast
Arkansas. Results indicate that both 15.2- and 30.4-cm diameter chambers were
similarly adequate for measuring CH4 fluxes and emissions from the
clay soil investigated. The similarity in emissions results between chamber
sizes also indicates that the 15.2-cm diameter chambers adequately facilitated
the quantification of CH4 emissions in this study.