Study on processes of dimethyl sulfide production in seawater, its emission to the marine atmosphere and formation of sulfate aerosol

为了对海水中悬浮颗粒物进行简单、快速的批量化学分析，研制了一种轻元素专用能量色散X射线荧光光谱仪。同时，我们还研制了一套基于氟化学发光的DMS浓度快速测量系统，并成功地将涡动相关法应用于船载海洋大气中，作为夏季在西亚北极北太平洋进行的铁施肥试验的一部分，进行了船载大气和海洋的同步测量（R/V Hakuho-maru）、春季初级生产力高峰期在三陆近海（R/V Tansei-maru）和夏季沿沿着47°N从西到东的副北极北太平洋（R/V米拉伊）进行调查。在铁肥引起的浮游植物水华期间，CH_3Br浓度升高。在19 '-己酰氧基岩藻黄素的浓度之间观察到线性相关性， ...更多信息 是几种原生植物的生物标志物。施肥后，CH_3Br在斑块内的海气通量由流入海洋转变为流出海洋。通过对亚北极西部海域水体和大气中二甲基硫、卤代甲烷和异戊二烯的测定，揭示了浮游植物的形态和生理差异可能与VOCs在大气和海水中分布的差异有关。对马暖流锋区海水中CH_3Br、CH_2I_2和CH_2CII等VOCs的高浓度与大气中VOCs的高浓度有一定的相关性。在沿着47°N的纵向断面上，观测到海水中DMS浓度在180°E ~ 140 V之间最高，相应地大气中DMS浓度也相应增加。同时，海水中颗粒态Ca的浓度随着海水中DMS浓度的增加而增加。CaCO_3试验结果表明，颗石藻碎屑能较好地反映海水中DMS的浓度。少

For simple and quick bulk chemical analysis of suspended particles in seawater, a devise with energy dispersive X-ray fluorescence spectrometer that specialized for light elements was developed. A fast measurement system of atmospheric DMS concentrations based on the fluorine-induced chemiluminescence was also developed and succeeded to employ in the marine air to apply the eddy correlation method on ship board.Our shipboard simultaneous measurements of air and sea were carried out as a part of the iron fertilization experiment in the western subarctic North Pacific in the summer (R/V Hakuho-maru), at the Off Sanriku region during the high primary productive period in the spring (R/V Tansei-maru), and survey along 47°N from western to eastern subarctic North Pacific in summer (R/V Mirai). During the phytoplankton bloom caused by iron fertilization, the concentrations of CH_3Br increased. A linear correlation was observed between the concentrations of 19'-hexanoyloxyfucoxanthin, which i … More s a biomarker of several prymnesiophytes, and CH_3Br in the seawater. After fertilization, the air-sea flux of CH_3Br inside the patch changed from influx to efflux from the ocean.Dimethylsulfide, halomethanes, and isoprene in the water and air measured in the western subarctic Pacific revealed that phytoplankton speciation and physiological differences are probably related to the differences of the distribution of VOCs in air and seawater. In the front region of Tsushima warm current, high concentrations of VOCs such as CH_3Br, CH_2I_2 and CH_2CII in seawater were correlated with in atmospheric concentrations. Results of the longitudinal transect along the 47°N, the highest DMS concentrations of seawater were observed between 180°E and 140V corresponding increases in the atmospheric DMS concentrations. At the same time, the concentration of particulate Ca in seawater increased with DMS concentration in seawater. It suggested that detritus of coccolithophorids with CaCO_3 test, reflect DMS concentration in seawater. Less