2009年12月对黄海进行了大面调查,研究了冬季黄海二甲基硫(DMS)和二甲巯基丙酸内盐(DMSP)的浓度分布、DMS海-气通量及其影响因素。调查结果表明,DMS、溶解态DMSP(DMSPd)和颗粒态DMSP(DMSPp)的浓度分别为0.95(0.07~3.30)、1.18(0.22~3.54)和5.01(1.63~12.33)nmol·L^-1。总体上DMS和DMSP的水平分布与叶绿素a(Chl-a)相类似,呈现近岸高、远海低的趋势。35°N断面的垂直调查结果显示,在水深小于50m的水体中Chl-a、DMS和DMSP浓度较高且分布相对均匀。相关性分析发现,仅DMSPp与Chl-a之间存在一定的相关性。利用Nightingale公式(N2000)估算了冬季黄海DMS的海-气通量,其平均值为2.16μmol·m^-2·d^-1。此外,根据大气气溶胶中甲基磺酸盐(MSA)和非海盐硫酸盐(nss-SO2-4)的浓度和比例,估算出生源硫释放对气溶胶中nss-SO2-4的贡献比例仅为2.85%,表明冬季黄海大气nss-SO2-4主要受人为活动排放控制。
The spatial distributions of dimethylsulfide(DMS)and dimethylsulfoniopropionate(DMSP)and sea-to-air flux of DMS as well as their influencing factors were studied in the Yellow Sea during December,2009.The surface water concentrations of DMS,dissolved DMSP(DMSPd)and particulate DMSP(DMSPp)were 0.95(0.07~3.30),1.18(0.22~3.54)and 5.01(1.63~12.33)nmol L-1,respectively.On the whole,the horizontal distributions of DMS and DMSP decreased offshore,with the same trend as chlorophyll a(Chl-a).Vertical distributions of Chl-a,DMS and DMSP along 35°N transect revealed high concentrations and uniform distributions in the upper 50 m water layer.A significant relationship between DMSPp and Chl-a was found in the surface water.Besides,the average sea-to-air flux of DMS was estimated to be 2.16μmol m-2 d-1 using the equation of Nightingale et al.(2000).Based on the concentrations of methanesulfonic acid(MSA)and non-sea-salt sulfate(nss-SO2-4),the relative contribution of biogenic sulfur to total nss-SO2-4was estimated to be 2.85%,implying that anthropogenic source is the major contribution to sulfur budget over the Yellow Sea in winter.