Rapid biological oxidation of methanol in the tropical Atlantic: significance as a microbial carbon source
Rapid biological oxidation of methanol in the tropical Atlantic: significance as a microbial carbon source
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DOI：
10.5194/bg-8-2707-2011
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发表时间：
2011-01-01
期刊：
影响因子：
4.9
通讯作者：
Nightingale, P. D.
中科院分区：
文献类型：
--
作者：
Dixon, J. L.;Beale, R.;Nightingale, P. D.
甲醇是大气中含量仅次于甲烷的第二大有机气体，在对流层中无处不在。它在大气氧化剂化学中起着重要的作用，并且具有地球化学活性。关于海洋是甲醇进入大气的源还是汇，存在很大的不确定性。人们对海水中的哪些反应决定其浓度以及穿过海面界面的通量的了解就更少了。我们在这里报告的甲醇浓度在151-296纳米之间的寡营养北大西洋的部分地区，与相应的微生物的吸收率在2-146纳米d（-1），表明周转时间低至1天（1-25天）的表面沃茨的寡营养热带东北大西洋。甲醇主要（>= 97%）被贫营养地区的微生物用于获得能量，这与20-50%可用于细胞生长的大陆架和沿海地区形成对比。微生物甲醇氧化速率与细菌亮氨酸吸收的平行测定的比较表明，甲醇平均贡献13%的细菌碳需求在中北方大西洋环流（最大54%）。此外，甲醇对细菌碳需求的贡献随叶绿素a浓度的幂函数而变化;这表明浓度
Methanol is the second most abundant organic gas in the atmosphere after methane, and is ubiquitous in the troposphere. It plays a significant role in atmospheric oxidant chemistry and is biogeochemically active. Large uncertainties exist about whether the oceans are a source or sink of methanol to the atmosphere. Even less is understood about what reactions in seawater determine its concentration, and hence flux across the sea surface interface. We report here concentrations of methanol between 151-296 nM in parts of the oligotrophic North Atlantic, with corresponding microbial uptake rates between 2-146 nM d(-1), suggesting turnover times as low as 1 day (1-25 days) in surface waters of the oligotrophic tropical North East Atlantic. Methanol is mainly (>= 97%) used by microbes for obtaining energy in oligotrophic regions, which contrasts with shelf and coastal areas where between 20-50% can be used for cell growth. Comparisons of microbial methanol oxidation rates with parallel determinations of bacterial leucine uptake suggest that methanol contributes on average 13% to bacterial carbon demand in the central northern Atlantic gyre (maximum of 54%). In addition, the contribution that methanol makes to bacterial carbon demand varies as a power function of chlorophyll a concentrations; suggesting for concentrations