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Gui-Peng Yang Maurice Levasseur Sonia Michaud Michael Scarratt 《Marine Chemistry》2005,96(3-4):315-329
Sixteen surface microlayer samples and corresponding subsurface water samples were collected in the western North Atlantic during April–May 2003 to study the distribution and cycling of dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) and the factors influencing them. In the surface microlayer, high concentrations of DMS appeared mostly in the samples containing high levels of chlorophyll a, and a significant correlation was found between DMS and chlorophyll a concentrations. In addition, microlayer DMS concentrations were correlated with microlayer DMSPd (dissolved) concentrations. DMSPd was found to be enriched in the microlayer with an average enrichment factor (EF) of 5.19. However, no microlayer enrichment of DMS was found for most samples collected. Interestingly, the DMS production rates in the microlayer were much higher than those in the subsurface water. Enhanced DMS production in the microlayer was likely due to the higher concentrations of DMSPd in the microlayer. A consistent pattern was observed in this study in which the concentrations of DMS, DMSPd, DMSPp (particulate) and chlorophyll a in the microlayer were closely related to their corresponding subsurface water concentrations, suggesting that these constituents in the microlayer were directly dependent on the transport from the bulk liquid below. Enhanced DMS production in the microlayer further reinforces the conclusion that the surface microlayer has greater biological activity relative to the underlying water. 相似文献
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海水中痕量DMS和DMSP分析方法的研究 总被引：7，自引：1，他引：6
二甲基硫（DMS）是海洋排放的占优势地位的生源硫气体,其在大气中的氧化产物能够影响到环境酸化和世界的气候变化.因此, 测定海水中的DMS对于准确地评价其在全球硫循环所起的重要作用具有重要意义.本文中作者研究了海水中DMS的痕量分析技术.海水中的DMS首先采用气提-冷阱捕集技术进行预浓缩, 然后用带有火焰光度检测器的气相色谱（GC-FPD）进行分析.该方法的精确度在5%以内, 平均回收率为85.6% （82.8%-90.5%）, 最小检出限为0.15 ng S.β-二甲基巯基丙酸内盐（DMSP）的分析是通过将其在碱性溶液中分解成DMS来进行.作者采用此方法实测了黄海中DMS和DMSP的含量, 获得了理想的结果. 相似文献
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《Polar Science》2014,8(3):306-313
Atmospheric dimethylsulfide (DMS) was measured to investigate the variation in its concentration over sea ice free oceans and sea ice regions of the Southern Ocean, using a proton transfer reaction-mass spectrometer (PTR-MS) on board the icebreaker Shirase from 1 December 2009 to 16 March 2010. In general, DMS concentrations over sea ice regions were very low compared with those over the sea ice free ocean. However, abrupt increases in DMS concentrations occurred over sea ice regions while the ship was moving and crushing the sea ice. Undoubtedly, the elevated DMS concentrations were caused by large DMS emissions from gaps in the ice made by the ship. During the period when Shirase had anchored off Syowa Station (69°00.4′S, 39°35.3′E), Antarctica, DMS concentrations were not detected. At this time, the surrounding sea of East Ongul island, on which Syowa Station is located, was completely covered with multi-year fast ice. Sea ice probably inhibits DMS emission from the ocean to the atmosphere. In addition, there was no evidence that chlorophyll a concentration in the sea water or wind speed above the sea surface affect atmospheric DMS concentrations over the sea ice free ocean regions. 相似文献