摘要
冻融作用对不同土壤pH值的重金属Zn赋存形态产生显著影响,以24 h为一个冻融周期,对Zn含量为150 mg.kg-1的黑土冻融8次的实验结果表明:pH值4.5～5.8,冻融作用促进交换态Zn含量略有增加,pH值5.8～9.5,交换态Zn含量降低;pH值5.0～9.5,冻融作用使得有机结合态Zn含量增加,pH值4.5～5.0时变化不显著;pH值4.5～9.5,冻融作用促进铁锰氧化物结合态Zn含量降低,残渣态Zn含量显著增加。pH值不同,冻融作用对重金属有效态的促进作用不同,低pH值时,冻融作用促进重金属Zn有效态增强,高pH值时,重金属有效态降低。
Freeze/thaw process is one of the important environment factors which can cause the soil physical - chemical and biological properties change. The impacts of pH on the Zn fractions transformation in black soil at the condition of freeze/thaw cycles （FTCs） were investigated. The results indicated that FTCs could promote the increasing of Zn exchangeable fraction slightly at pH value 4.5 to 5.8 and decreasing at pH value 5.8 to 9.5 ; FTCs could promote the increasing of Zn organic matter binding fraction at pH value 5.0 to 9.5 and changing a little at pH value 4.5 to 5. O; FTCs could promote the decreasing of Zn iron - manganese oxides binding fraction and the increasing of Zn residual fraction prominently. FTCs could promote the increase of validity of heavy metals at low pH value and adversely trend at high pH value.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2010年第1期163-167,共5页
Journal of Arid Land Resources and Environment
基金
国家重点基础研究发展规划项目(编号:2004CB418507)
中国科学院东北地理与农业生态研究所前沿领域项目(编号:KZCX3-SW-NA3-14)资助
关键词
重金属ZN
形态转化
pH值
冻融交替
黑土
heavy metal Zn
fraction transformations
pH value
freeze/thaw cycles
the black soil
