Ebullition of methane-containing gas bubbles from near-surface Sphagnum peat -: art. no. L21505
Ebullition of methane-containing gas bubbles from near-surface Sphagnum peat -: art. no. L21505
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DOI：
10.1029/2004gl021157
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发表时间：
2004-11-05
影响因子：
5.2
通讯作者：
Waddington, JM
中科院分区：
文献类型：
--
作者：
Baird, AJ;Beckwith, CW;Waddington, JM
迄今为止，关于泥炭地表面（1m以上）附近分解不良的泥炭中生物气泡的积累和释放的信息很少。我们在8个（直径24 cm，深度22 cm）分解不良的近地表沼泽泥炭岩心中研究了生物气泡沸腾作为CH4向大气输送机制的重要性。除了一个样品外，所有样品都记录了沸腾，但样品之间差异很大。通过沸腾排出CH4的最大速率也变化很大，范围从2.2到83.0 mg CH4 m（-2）天（-1）。这些速率与扩散CH4外排速率相似。我们的研究结果还表明，湿地甲烷模型可能需要修订，因为它们假设在气泡产生之前需要不切实际的高CH4孔隙水浓度，而且部分原因是它们没有考虑气泡在沸腾之前的积聚。
[ 1] To date, very little information has been available on the build-up and release of biogenic gas bubbles in poorly-decomposed bog peats near the peatland surface ( upper 1 m). We investigated the importance of ebullition of biogenic gas bubbles as a mechanism for the transport of CH4 to the atmosphere in eight cores ( 24 cm diameter, 22 cm depth) of poorly-decomposed, near-surface bog peat. Ebullition was recorded in all but one sample but varied greatly between samples. Maximum rates of CH4 efflux via ebullition were also highly variable, ranging from 2.2 to 83.0 mg CH4 m(-2) day(-1). These rates are similar to rates of diffusive CH4 efflux. Our results also show that wetland methane models are likely to need revision because they assume that unrealistically high CH4 pore-water concentrations are required before bubbles can be produced and because, in part, they do not account for gas bubble build-up prior to ebullition.