模拟酸雨对菜园土壤施用猪粪后重金属释放的影响

    采用平衡培养方法,研究模拟酸雨对菜园土壤施用富含重金属猪粪后重金属释放的影响结果表明,pH 36的模拟酸雨培养10 d可导致菜园土壤明显酸化,土壤溶液中Cu、Zn、Cd、Pb等重金属浓度和累积释放量显著高于pH 56的对照溶液,其中Zn和Cd的差异尤为明显,As的情况则相反尽管施用富含重金属的猪粪能缓解土壤的酸化,但菜园土壤培养液中重金属浓度显著高于对照,尤其是Zn和Cd可见,在酸雨沉降频繁的地区大量施用富含重金属的畜禽粪便,将会增加重金属对蔬菜和生态环境污染的风险

Effect of simulated acid rain on release of heavy metals from vegetable soil amended with swine manure

Equilibrium incubation was employed to study the effect of simulated acid rain on release of heavy metals from the vegetable soils amended with metal-rich swine manure. The results show that incubated with acid rain of pH 3.6, in comparsion with control (pH 5.6), accelerated the soil acidification and increased the concentrations and cumulative release amounts of Cu, Zn, Cd and Pb, whereas the opposite trend was observed for arsenic. Furthermore,vegetable soil amended with metal-enriched swine manure would result in higher concentrations and cumulative release amounts of Zn and Cd incubated by acid rain of pH 3.6 relative to pH 5.6, although manure could buffer the acidification of soils. It is suggested that heavy application of metal-rich swine manures to vegetable soils in the areas subjected to acid rain deposition with high-frequency would increase a potential risk of heavy metal contamination to vegetables and ecological environment.