重金属污染黄壤生态修复中的微生态效应

Effect of Microbial Ecology in Restoring Ecology of Yellow Soils Polluted by Heavy Mental Nickel

以黄壤作为供试土壤,种植重金属富集植物与非富集植物,采用室内培养方法对外加镍污染黄壤的微生物活性及其群落结构进行了研究。结果表明:较低浓度Ni有利于提高土壤微生物活性,当Ni浓度>100 mg/kg时供试土壤的微生物活性开始下降,其中微生物生物碳、氮量和基础呼吸随重金属浓度增加而明显下降,但种植重金属富集植物的土壤下降幅度明显低于种植非富集植物的土壤。结果还显示,镍严重污染破坏了土壤微生物区系,使土壤细菌、放线菌及真菌数量下降,其中放线菌对重金属毒性影响最为敏感,重金属富集植物车前草引起土壤微生物区系的变化较小,表现了良好的修复能力。

Incubation experiment tested to the effect of nickel (Ni) applied on soil microbial activities and popula- tions constitution in yellow soils. The results showed that lower concentration of nickel helps the microbial activi- ties, but higher concentration or more than 100 mg/kg caused the activities to decrease. Studies suggest that soil microbial biomass carban, nitrogen and soil basal respiration decreased apparently with the increasing of concentra- tion of nickel. The number of decrease of microbial activity is lower in yello soil which is planted Hyperaccumu- lator plant than non-hyperaccumulator one. Moreover, the experiment revealed that soil microbial populations constitution have changed to some extent under stress pollution by nickel. The number of soil bacterial, acttino- mycetes and fungus decrease greatly compared with non-polluted soil samples. The soil acctinomycetes is the best sensitive for heavy mental pollution. Hyperaccumulator plant caused the lesser variety of soil microbial populations constitution and contribute to resume soil ecology.