摘要
在模拟酸雨作用下 ,研究了重金属污染和未污染的酸性红壤和黄红壤中铝和水溶性有机质的溶出以及对重金属活动性的影响。结果表明 ,随模拟酸雨pH值下降 ,土壤pH值和盐基饱和度明显降低 ,而交换性酸度明显增加 ,污染土壤中交换性氢含量比未污染土壤高 ,而交换性铝含量比未污染土壤低。铝溶出量与模拟酸雨pH值密切相关 ,当模拟酸雨pH值在 5 .60～ 3.5 0时 ,供试红壤浸出液中铝浓度几乎在同一水平 ;当pH≥ 4 .5 0时 ,供试黄红壤中溶出铝亦未明显变化 ;当模拟酸雨pH =3.5 0时 ,未污染黄红壤中铝溶出明显增多 ;当pH =3.0 0时 ,供试土壤中铝溶出量急剧增加。随模拟酸雨pH值下降 ,污染土壤中铝溶出比未污染土壤低 ,而有效态重金属活动性明显增加 ;污染土壤中水溶性有机质比未污染土壤溶出明显增加 ,水溶性有机质 -重金属络合体促进了重金属的溶解迁移行为。
Through continuous bathe equilibrium experiments, the release of aluminum and dissolved organic matter (DOM), and mobility of heavy metals affected by simulated acid rain in contaminated acidic red soil and yellow red soil were studied. The results showed a decrease of pH and base saturation, and increase content of exchangeable acidity in both uncontaminated and contaminated red soil and yellow red soil within the pH decreasing of simulated acid rain, significantly. The content of exchangeable hydrogen is higher and exchangeable aluminum is lower in contaminated soils compared to uncontaminated soils. The release of aluminum was mainly affected by pH of simulated acid rain. At simulated acid rain pH of no less than 4.50, the release was almost the same in tested soils. At simulated acid rain pH of 3.50, the release was almost the same in red soil and different in yellow red soil, obviously. At simulated acid rain pH of 3.00, the release was improving significantly in tested soils. However, the release of aluminum was less in contaminated tested soils than in un-contaminated tested soils, and, at the same time, the mobility of available heavy metals in contaminated tested soils was increased significantly. The release of DOM increased in contaminated red soil and yellow red soil by simulated acid rain, and the complex of DOM- metal is useful for release and transport of available heavy metals.
出处
《土壤学报》
CAS
CSCD
北大核心
2003年第3期380-385,共6页
Acta Pedologica Sinica
基金
教育部科学技术研究重点项目 ( [2 0 0 0 ]1 5 6-0 0 2 0 9)
科技部中法先进研究计划项目 (PRAE0 0 -0 4 )
关键词
模拟酸雨
红壤
铝
水溶性有机质
溶出
重金属
活动性
土壤污染
Simulated acid rain, Heavy metals, Aluminum, Dissolved organic matter, Bathe equilibrium experiment
