耐铬菌群特性及其修复土壤铬污染的条件优化

摘要

[目的]筛选及鉴定7耐铬菌群,以期为土壤铬污染治理提供帮助.[方法]从铬污染土壤中筛选、驯化获得耐重金属铬菌液,经分离纯化得到6株纯菌株,经形态观察、生理生化实验、16S rDNA序列分析和系统发育分析对其进行鉴定,同时用该修复菌液对人为添加重金属铬(Ⅵ)污染的土壤进行修复试验研究.[结果]土壤中添加优势修复菌液,可增加铬(Ⅵ)的还原能力:只添加菌液的寡营养土壤铬(Ⅵ)污染去除率为60.0％ ～99.5％；添加营养菌液的富营养土壤铬(Ⅵ)去除率为92.0％～99.6％.[结论]修复菌液最适pH为7.5,最适温度为30 ℃,加入牛粪可以显著加速铬(Ⅵ)的修复效果.%[ Objective ] The aim was to screen and identify chromium resistant bacteria, to provide help for the governance of chromium contaminated soil. [Methods] Chromium resistant bacteria liquid were screened from chromium contaminated soil, and through separation and purification, six bacteria were obtained and identified based on morphologic observation, physiological and biochemical experiment, 16S rDNA sequence analysis and phylogenetic analysis. Meanwhile, using these bacteria to remediate the contaminated soil by adding chromium ( VI) were studied. [ Result ] Adding the advantageous remediation bacteria to the soil can increase the capability for reducing concentration of chromium ( VI) . The removal rate is 60% - 99. 5% while only adding bacteria liquid to oligotrophic chromium ( VI) polluted soil. And the removal rate is 92% -99.6% while adding eutrophy bacteria liquid to nutrient-rich chromium (VI) contaminated soil. [Conclusion] The optimum pH of remediation bacteria liquid is 7.5, and the optimum temperature is 30 ℃. To add cattle dung can increase the remediation effect for chromium ( VI) significantly.