Effects on the Hydrological Environment by the Ash Fall due to the Volcanic Eruption of Mt.Sakurajima.

Research Project

Project/Area Number	60580203
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	自然地理学
Research Institution	Kagoshima University
Principal Investigator	TSUKADA Kimihiko Kagoshima Univ. Professor., 教育学部, 教授 (40041181)
Co-Investigator(Kenkyū-buntansha)	YAMASHITA Shuji Tokyo Gakugei Univ. Professor., 教育学部, 教授 (80064731)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥1,700,000 (Direct Cost: ¥1,700,000) Fiscal Year 1986: ¥300,000 (Direct Cost: ¥300,000) Fiscal Year 1985: ¥1,400,000 (Direct Cost: ¥1,400,000)
Keywords	Volcanic eruption / Ash fall / Hydrological environment / 酸性雨(雨水のpH値) / 酸性雨(雨水のPH値)
Research Abstract	The low PH value in the rain water (acid rain) is observed recently here and there not only worldwide but in our country. And it becomes now a serious probrem as an origin of the widespread environmental pollution. The purpose of this investigation was to clarify the actual condition of the acid rain in the field around Mt.Sakurajima, kagoshima prefecture. In order to attain the purpose, within a research period (1980.9-1981.3), the rain water samples from 4 observed stations were collected with the bulk sampling method for a rainfall. The PH values of the river waters, the lake waters and the spring waters were also measured by using PH meter (Model 51, Yokokawa-Hokushin K.K.) at the each sampling station. The number of the sampling stations were about 130 sts. The results of this research are summarized as follows; 1. The average PH value was included between 4.0 and 5.0 for 4 stations, and especially on the station installed at Kagoshima Univ. it showed bellow 4.5. 2. The result mentioned ahove shows that the PH values vary according to the wind direction when the volcanic eruption occured. 3. The obvious influences to the hydrological environment were not ovserved from this research. And the annual change were not so clear in this period. 4. It is necessary to be carried on this kind of research in future.