土壤中石油烃与降解菌群的相互作用研究

Research on Interaction between Petroleum Hydrocarbon and Degrading Bacteria Consortium in Soil

以江汉油田石油污染土壤为研究对象,通过室内模拟修复试验,向石油污染的土壤中添加降解菌群的营养液后,在不同处理时间检测土壤中的石油烃含量、组成以及微生物的活性、多样性和功能基因的变化,研究土壤中石油烃与微生物的相互作用规律。试验结果表明:在添加LB培养基菌悬液的土壤中石油烃在35d内降低了30%,其中低分子量正构烷烃和多环芳烃先降解,高分子量正构烷烃和多环芳烃后降解,同时生成低分子物质;采用ARISA技术对DNA-ITS-PCR产物分析发现,降解菌群添加至土壤后很快成为优势菌,但随着时间的延长土壤微生物多样性发生较大的变化,微生物功能基因多样性检测显示,降解菌群处理土壤前期微生物可能主要以烷烃降解过程中生成的醇类等物质为底物,而后期可能以芳香类降解过程中生成的酚羟类物质为底物。

This paper takes the contaminated soil collected from the petroleum pollution repair site in jiang- han oilfield as the research object and aims to study the interaction between petroleum hydrocarbon and mi- crobes in soil through the indoor repair simulation experiment, which adds bacteria consortium to the oil- polluted soil and measures the content and composition of petroleum hydrocarbon, microbial activity and the diversity of microbes and functional genes in different processing time. The results show that petroleum hydrocarbon content decreases by 30 G in 35 days in the soil treated with degrading bacteria consortium in LB media. Among the petroleum hydrocarbons,n-alkanes and polycyclic aromatic hydrocarbons （PAHs） with lower molecular weight decrease first, and then that with higher molecular weight degrades into smal- ler organic molecules. According to the results of DNA-ITS-PCR product analysis using ARISA, the de- grading bacteria quickly becomes dominant species after entering into the soil. However,the microbial di- versity changes much with culture time, and some new significant species appeare. The results of functional gene diversity showe that bacteria consortium mainly uses alcohols derived from the degradation of alkanes as substrate in the previous stage,and uses phenols-hydroxyls derived from the degradation of aromatic hy- drocarbons as substrate.