Abstract: The effect of leakage amount of K⁺,Ca²⁺ and Mg²⁺ in leaves with different pH of simulated acid rain was investigated by spraying experiments.After a certain period of acid rain stress time,the leakage amount of K⁺,Ca²⁺ and Mg²⁺ in leaves of Alnus formosana seedlings decreased with the increasing of pH value,showing a negative correlation effect.The leakage amount of K⁺ in leaves of treatment I-V decreased by 34%,25.5%,17.4%,16.7%,11.4% compared with the control (CK);the leakage amount of Ca²⁺ in leaves of treatment I-V decreased by 36%,25%,18%,5%,3% compared with the control (CK);the leakage amount of I-V treatment of Mg2+ in leaves decreased by 58.3%,41.6%,37.5%,29.2%,22.1% compared with the control (CK).The changes of leakage amount of K⁺ and Mg²⁺ in leaves generally increased firstly and decreased afterwards with the prolonging of stress time,but the leakage amount of Ca²⁺ gradually decreased.

Key words: simulated acid rain, Alnus formosana, leakage amount