模拟酸雨对林地黄壤汞溶出的影响

以缙云山上的3种森林林被黄壤为供试土壤,通过模拟pH 2.0、pH 3.0、pH 4.0、pH 5.0的酸雨对上述土壤的动态淋溶试验,研究酸雨对林地土壤汞溶出的影响.结果表明:阔叶林地汞的溶出总量在酸雨pH 3.0、4.0时最低,但各pH的酸雨对阔叶林地汞的溶出量之间的差异不显著.针叶林地和竹林地汞的溶出总量随pH降低而升高,在pH 2.0的酸雨作用下,与pH 3.0、4.0、5.0的酸雨间的差异达极显著水平.在强酸雨的作用下,针叶林和竹林土壤的汞更易迁出土壤而污染水体.因此应加强森林土壤的管理,禁止取材,以提高土壤有机质,抑制汞的水迁移.

Effect of Simulated Acid Rain on Mercury Leaching from Forest Yellow Soil

Forestry yellow soils in Jinyun Mountain are collected to study the effect of simulated acid rain( adjusted to pH 2.0, 3.0, 4.0, 5.0) on the Hg leaching from soils by the methods of dynamic leaching. The results show that in forest yellow soils, the amount of leached Hg from Broadleaf soil is the lowest at pH 4.0, but the difference among each pH hasn't reached to the significant level. The amounts of leached Hg from Coniferous and Bamboo soil go up with the fall of pH,and the difference between pH 2.0 and pH 3.0, 4.0, 5.0 has reached to the strong significant level. The Hg in Coniferous and Bamboo soil is easy to be leached out than that in Broadleaf soil by strong acid rain and polluted the water body. To abate the risk of Hg pollution in water bodies by the Hg leaching from this forest soil, the management of Mountain should be enhanced, and timber-felling should be forbidden.