Low-molecular-weight hydroxyacids in marine atmospheric aerosol: evidence of a marine microbial origin
Low-molecular-weight hydroxyacids in marine atmospheric aerosol: evidence of a marine microbial origin
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DOI：
10.5194/bg-11-4407-2014
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发表时间：
2014-08
期刊：
影响因子：
4.9
通讯作者：
Y. Miyazaki;Maki Sawano;K. Kawamura
中科院分区：
文献类型：
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作者：
Y. Miyazaki;Maki Sawano;K. Kawamura
乳酸（LA）和乙醇酸（GA），这是低分子量的羟基酸，被确定在颗粒和气相内的海洋大气边界层在西亚北极北太平洋。大部分的LA（81%）和GA（57%）存在于颗粒相中，这与这些分子中存在羟基一致，导致化合物的低挥发性。受生物影响较大的海洋气溶胶中LA的平均浓度（±SD）（33 ± 58 ng m −3）显著高于受生物影响较小的气溶胶（11 ± 12 ng m −3）。在浮游植物水华的海洋区域，气溶胶LA的浓度是可比的草酸，这是最丰富的二元酸在研究期间。在更多生物影响的气溶胶中的LA浓度与海水中的叶绿素a之间发现了正相关性（r 2 = 0.56），这表明气溶胶LA的重要产生可能与微生物（例如，（3）海水和/或气溶胶中的放射性。我们的发现提供了一个新的见解海洋有机气溶胶（OAs）的微生物来源的量化差，因为这种低分子量的羟基酸是OA形成的关键中间体。
Lactic acid (LA) and glycolic acid (GA), which are low-molecular-weight hydroxyacids, were identified in the particle and gas phases within the marine atmospheric boundary layer over the western subarctic North Pacific. A major portion of LA (81%) and GA (57%) was present in the particulate phase, which is consistent with the presence of a hydroxyl group in these molecules leading to the low volatility of the compounds. The average concentration (±SD) of LA in more biologically influenced marine aerosols (33 ± 58 ng m −3 ) was substantially higher than that in less biologically influenced aerosols (11 ± 12 ng m −3 ). Over the oceanic region of phytoplankton blooms, the concentration of aerosol LA was comparable to that of oxalic acid, which was the most abundant diacid during the study period. A positive correlation was found between the LA concentrations in more biologically influenced aerosols and chlorophyll a in seawater ( r 2 = 0.56), suggesting an important production of aerosol LA possibly associated with microbial (e.g., lactobacillus) activity in seawater and/or aerosols. Our finding provides a new insight into the poorly quantified microbial sources of marine organic aerosols (OAs) because such low-molecular-weight hydroxyacids are key intermediates for OA formation.