黄、东海溶解态无机砷的形态及其分布

Species and distribution of dissolved inorganic arsenic in the Yellow Sea and East China Sea

利用氢化物发生原子荧光光谱法对2000年10月和2001年5月航次黄、东海的无机砷进行了测定。两个航次中黄、东海总溶解态无机砷(TDIAs)含量的变化范围分别为9.6～21.6和12.9～23.2 nmol/L,亚砷酸盐(As3+)含量的变化范围分别为0.02～2.44和0.01～9.52 nmol/L,2000年秋季TDIAs和As3+的含量明显低于2001年春季。长江对黄、东海的影响非常显著,是主要的物质来源之一。黄海溶解态无机砷的平面分布表现为沿岸和东黄海交界处高,黄海中部冷水团区含量较低。东海自长江口向西南琉球群岛沿伸的PN断面中,TDIAs和As3+的分布存在明显的梯度,自长江口向中央海区递减,然后由于受到黑潮水入侵含量又开始升高。东海陆架区As3+的含量、分布受到浮游植物活动的影响,表现出与叶绿素含量存在相关关系。

The total dissolved inorganic arsenic （TDIAs） and arsenite （As^3 ＋ ） ,which were measured by Hydride Generation-Atomic Fluorescence Spectrometry （HG-AFS） are presented here. The field observations were undertaken through the cruises of《R/V Dong fang hong 2》in the Yellow Sea and East China Sea in Oct. -Nov. 2000 and May 2001. The concentrations of TDIAs ranged from 9.6 -21.6 μmol/Land 12.9 -23.2 μmol/L for the cruises of Oct. 2000 and May 2001 in the Yellow Sea and East China Sea, respectively. The concentrations of As^3 ＋ ranged from 0.02 - 2.44 μmol/L and 0.01 - 9.52 μmol/L for two cruises, respectively. The concentrations of TDIAs and As^3＋ in Oct, 2000 were lower than May 2001. The impact of Changjiang on the Yellow Sea and East China Sea is very important and the main terrestrial sources in the studied area, The concentrations of TDIAs and As^3 ＋ in the central Yellow Sea Cold Water Center was lower than the coastal area and joint of Yellow Sea and East China Sea, There are the obvious concentration gradients for TDIAs and As^3 ＋ in the southeast PN section which from the Changjiang Estuary to Ryukyu Islands. The concentrations of TDIAs and As^3＋ were decreased gradually from the Changjiang Estuary to the central of ECS Shelf, and then were increased since the incursion of Kuroshio Subsurface Water. There is the correlated relationship between As^3 ＋ and Chl-a. R showed that the concentrations and distribution of As^3 ＋ were affected by the phytoplankton activities.