Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries
Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries
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DOI：
10.1073/pnas.0404412101
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发表时间：
2004-08-24
影响因子：
11.1
通讯作者：
Vile, M
中科院分区：
文献类型：
--
作者：
Gauci, V;Matthews, E;Vile, M
天然湿地是大气中甲烷（CH4）的最大来源。众所周知，这种强大的温室气体从湿地的排放取决于气候，气温和降雨的增加都预计会增加甲烷的排放。本研究结合了我们在欧洲和北美的野外和受控环境操纵研究，揭示了一个额外的控制：在全球酸沉积范围内，随着硫酸盐（SO42-S） 4沉积的增加，泥炭地甲烷（CH4）排放的抑制增加。我们应用这种关系的一个模型来证明从1960年到2080年全球硫酸盐沉降变化对北部泥炭地和全球湿地CH4排放的潜在影响。我们估计，硫污染目前可能抵消了湿地源中气候引起的生长，减少了大约15 Tg的CH4排放，比没有全球酸沉积时减少了8%。我们的研究结果表明，到2030年，硫污染可能足以使CH4排放量减少26 Tg或占总湿地源的15%，这一比例与迄今为止受到更大关注的CH4预算的其他组成部分一样大。我们的结论是，自19世纪末以来记录的大气CH4浓度的增加可能是由于湿地全球变暖以外的因素。
Natural wetlands form the largest source of methane (CH4) to the atmosphere. Emission of this powerful greenhouse gas from wetlands is known to depend on climate, with increasing temperature and rainfall both expected to increase methane emissions. This study, combining our field and controlled environment manipulation studies in Europe and North America, reveals an additional control: an emergent pattern of increasing suppression of methane (CH4) emission from peatlands with increasing sulfate (SO42-S) 4 deposition, within the range of global acid deposition. We apply a model of this relationship to demonstrate the potential effect of changes in global sulfate deposition from 1960 to 2080 on both northern peatland and global wetland CH4 emissions. We estimate that sulfur pollution may currently counteract climate-induced growth in the wetland source, reducing CH4 emissions by approximate to15 Tg or 8% smaller than it would be in the absence of global acid deposition. Our findings suggest that by 2030 sulfur pollution may be sufficient to reduce CH4 emissions by 26 Tg or 15% of the total wetland source, a proportion as large as other components of the CH4 budget that have until now received far greater attention. We conclude that documented increases in atmospheric CH4 concentration since the late 19th century are likely due to factors other than the global warming of wetlands.