カゴシマシ ノ タイキ オセン チョウサ ダイ21ポウ ヘイセイ 19ネンド チョウサ ホウコク

Air pollution in Kagoshima City from April 2007 to March 2008 was investigated with particular emphasis on the falling dust (volcanic ash fall) from Mt. Sakurajima. The falling dust was collected monthly with rainwater at eight locations in Kagoshima City. After the sample had been filtered, the residue was dried and weighed, and the filtrate was analyzed for SO_4＾< 2->, Cl＾-, and water-soluble matter, as well as for pH. The average monthly falling dust at the eight locations in Kagoshima City was 6.3 g·m＾<-2>·month＾<-1>, which was about the same as that observed in the last fiscal year. The tendency of low falling dust has continued since 2001. The concentration of NO_2 in the air was measured by use of the "filter-badge method". The average NO_2 concentration at the eight locations was 7.7 ppb, which was ca. 20% lower than those for the recent years