Linear discriminate analysis on annual and seasonal characteristics of major cations' profiles of rainwater at Zhoushan rain-sampling spot

Rainwater samples were collected at rain-sampling spot of Zhoushan in 2002 ~ 2003, major cation concentrations (H⁺ , NH₄⁺ ,K⁺ ,Na⁺,Ca²⁺, Mg²⁺ ) of rainwater sample were determined. The concentration variation range and character were depicted by robust statistic analysis. Linear discriminate analysis(LDA) was used to acquire a further knowledge on the annual and seasonal characteristics of research major cations. Distribution character of samples from sample spot was clearly depicted in the new CA1-CA2 ordinates generated by linear discriminate analysis, and the reasons that caused the outliers in samples were discussed.