山形県鶴岡市の日本海沿岸部におけるケイ素,ナトリウムおよび硫酸の大気圏降下量

抄録

Atmospheric deposition samples were collected biweekly from April 1989 to June 1990 at coast of the Japan Sea in Tsuruoka. The samples were analyzed for Si, Na and SO₄^2-. The deposition rate of particulate-Si showed spring peak as well as that of the atmospheric concentration. The annual deposition rate of aluminosilicate at the station was 12 g m^-2 y^-1. This value was one order of magnitude larger than that in the central North Pacific region. The atmospheric annual deposition rate of SO₄^2- was 16.1 g m^-2 y^-1 and 25% of this value was nonsea salt fraction. This deposition rate of nonsea salt SO₄^2- in winter (Nov. -Mar. ) was larger than that in other seasons. A large part of this nonsea salt SO₄^2- may be originate in air pollution of northern hemisphere.