1994 Fiscal Year Final Research Report Summary
Evaluation of sulfate from Asian continets in wet and dry deposition in Tohoku District, Japan
| Project/Area Number |
05640544
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
地球化学
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| Research Institution | Yamagata University |
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Principal Investigator |
YANAGISAWA Fumitaka Yamagata University, Faculty of Sciece, Department of Geoscinces Assistant Professor, 理学部, 助手 (00239807)
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| Project Period (FY) |
1993 – 1994
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| Keywords | Tohoku District / Acidic Deposition / Acid Rain / Aerosol / Air-Sampler / Sulfur Isotope / Yamagata |
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| Research Abstract |
Wet deposition was collected every month from 1990 to 1995 at Sakata, Shinjo, Yamagata, Ohfunato, Okushiri and Yonezawa in Tohoku District, Japan. And Dry deposition was collected with High Volume Air Sampler from 1992 to 1995 at Tsuruoka and Yamagata. Sulfur isotope ratios of sulfate were low in summer and high in winter, linked with the contribution of sea-salt sulfate. The sulfur isotope ratio in deposition in less than that of seawater sulfate (^+20.3%). This result suggested that the main sources of sulfate in this area did not come from sea spray sulfate. The sulfur isotope ratios for non-seasalt sulfate show seasonal variation (low in summer and high in winter). It is conclude that sulfate in the deposition contains sulfur-oxides from human activities of Asian continent.
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