环球海洋大气气溶胶化学研究──Ⅲ:金属形态和入海通量

A Study of Aerosol Chemistry in the Atmosphere over Oceans Part-Ⅲ: Forms and Air-Sea Fluxes of Metal

中国第三次南极考察和环球科学考察，历经北太平洋、南太平洋、南极半岛海域、南大西洋、北印度洋、以及沿途近岸海域，共收集58个气溶胶样品，采用石墨炉原子吸收法分析其中的水可溶态和酸可溶态的Mn、Fe、PhCu、Cd。气溶胶中金属表现明显陆源向大洋输送的浓度梯度，近岸海域上空金属含量大于大洋上空含量，北太平洋上空含量高于南太平洋和南极半岛海域。气溶胶中金属的水可溶程度，在近岸海域上空依次为Cd＞Mu＞Cu＞Fe＞Pb，百分比分量分别为39％，36％，23％，14％和5．3％在大洋上空依次为Cd＞Mn＞Fe＞Cu＞pb，百分比分量分别为62％，44％，11％，3．1％和2．5％。本文还计算和比较各观测海区上空金属从大气输入海水的通量。

Fifty eight aerosol samples were collected in the atmosphere over the North Pacific, the South Paci-fic, the Antarctic Peninsula waters, the South Atlantic, the North Indian Oeean, and near shore waters during the Third Chinese Antarctic Expedition and Global Scientific Research Experiment. An atomic absorption spectrophotometry was used to determine water soluble and acid leachable concentrations of Mn, Fe, Pb, Cu and Cd in the aerosols. Concentrations of aerosol metal show obvious gradient in the transport process from the continent to the ocean. The concentration of metals in aerosols is higher in the near shore atmosphere than that in the ocean atmosphere. The contents of metals in aerosols over the North Pacific are higher than those over the South Pacific or over the Antarctic Peninsula waters-The order of water solubilites of aerosol metal over the near shore waters is Cd > Mn > Cu>Fe >Pb with the water soluble fraction of 39%, 36%, 23%, 14% and 5.3%, respectively, and the order over the ereans is Cd > Mn > Fe > Cu >Pb with 62%, 44%,11%,3.1% and 2.5%, respectively. The fluxes of metals from air to sea were also estimated for the investigated shores and oceans.