Abstract
The ion composition of rain, which had been collected from September in 1993 to March in 1996 at Kansai research center, Forestry and Forest Product Research Institute in Kyoto city, was investigated. Monthly ion composition showed that Ca^<2+>, Na^+ and H^+ occupied 80% of total cations accompanied by NH_4^+, Mg^<2+> and K^+ and SO_4^<2->, NO_3^- and Cl^- occupied 98% of total anions. It was observed that Na^+, Mg^<2+> and Cl^- contents increased in winter season and NH_4^+, NO_3^- and NO_2^- contents increased in summer season. Comparing monthly precipitation with monthly ion composition, the monthly ion composition was almost constant in the month of much rain as a result of the increase of H^+ and SO_4^<2-> contents and the decrease of the other ion contents with increasing monthly precipitation.
