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Methane accumulation in chambers before (open symbols) and after (closed symbols) treatment with acetylene overnight (about 12 h); data represent means from triplicate chambers (1 standard error). Incubations were initiated at 1029 on 2 August (E), 1619 on 2 August (), 0837 on 3 August (F), 1553 on 3 August (s), and 0820 on 4 August (å). All posttreatment slopes are statistically greater than pretreatment slopes (P 0.05); there are no statistically significant differences within pre-and posttreatment groups (P 0.05). The estimated relative methane oxidation was 24%.  

Methane accumulation in chambers before (open symbols) and after (closed symbols) treatment with acetylene overnight (about 12 h); data represent means from triplicate chambers (1 standard error). Incubations were initiated at 1029 on 2 August (E), 1619 on 2 August (), 0837 on 3 August (F), 1553 on 3 August (s), and 0820 on 4 August (å). All posttreatment slopes are statistically greater than pretreatment slopes (P 0.05); there are no statistically significant differences within pre-and posttreatment groups (P 0.05). The estimated relative methane oxidation was 24%.  

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Methane oxidation associated with the belowground tissues of a common aquatic macrophyte, the burweed Sparganium eurycarpum, was assayed in situ by a chamber technique with acetylene or methyl fluoride as a methanotrophic inhibitor at a headspace concentration of 3 to 4%. Acetylene and methyl fluoride inhibited both methane oxidation and peat metha...

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... rates measured in situ during early August (Fig. 4C). Means ranged from 13.1 to 15 mol of CO 2 Methane emission and oxidation associated with S. eu- rycarpum. Methane accumulated linearly in chambers with S. eurycarpum during short-term assays after incubation with a 3 to 4% gas-phase concentration of acetylene or methyl fluoride for about 12 h (Fig. 5). Rates of methane accumulation after incubation with one of the inhibitors were consistently greater than emission rates determined during a 10-to 24-h period prior to inhibitor addition. In a comparative analysis, emission rates after incubation with acetylene or methyl fluoride were similar (Fig. 5), as was the estimated percent ...
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... acetylene or methyl fluoride for about 12 h (Fig. 5). Rates of methane accumulation after incubation with one of the inhibitors were consistently greater than emission rates determined during a 10-to 24-h period prior to inhibitor addition. In a comparative analysis, emission rates after incubation with acetylene or methyl fluoride were similar (Fig. 5), as was the estimated percent methane oxida- tion (29 and 25%, respectively); emission rates also appeared stable for up to 36 h subsequent to incubation with either ...
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... of chambers in situ (Fig. 5) indicates that any inhibition of methanogenesis had a minimal effect on methane emission, as observed for in vitro incubations with rice (16,18). The lack of an observable effect of methane inhibition during the cham- ber incubations suggests that the supply of methane for emis- sion through plants was independent of short-term ...
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... similarity of methane oxidation rates measured in situ with acetylene or methyl fluoride (Fig. 5), the absence of any effects on photosynthesis and stomatal resistance, and the com- parable effects of both gases on in vitro methane production and oxidation indicate that either can be used for field studies of plant-associated methane oxidation. The low cost and con- venience of acetylene (i.e., its availability as calcium carbide) ...

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