桑园土壤微生物群落功能多样性对PAHs污染的响应

为了探明桑园土壤微生物群落功能多样性与多环芳烃(PAHs)污染的关系,采用Biolog检测法研究某路域桑园土壤微生物功能多样性对PAHs污染的响应。结果表明,不同区域PAHs污染程度由大到小依次为区域2(位于区域1和3之间)、3(离公路最远)和1(离公路最近);Biolog分析发现不同区域土壤微生物对碳源利用的平均颜色变化率(AWCD)由大到小依次为区域2、3和1;区域2的Shannon指数和Gini指数均显著高于区域1和3,而区域1的Shannon均匀度显著低于区域2和3,区域2土壤微生物活性最强且群落结构最丰富,其后依次为区域3和1。主成分分析结果显示,3个区域微生物群落的生理功能差异明显,主要表现在对糖类和氨基酸类物质的代谢上。冗余分析表明,区域2土壤微生物与PAHs含量关系最密切,说明较高的PAHs含量更能激发桑园土壤微生物的生理活性,微生物群落代谢功能因PAHs污染而有所提高。

Response of Soil Microbial Community in Mulberry Garden to PAHs Pollution in Functional Diversity

For the purpose of understanding relationships of functional diversities of soil microbial communities in mulberry gardens with the pollutants of polycyclic aromatic hydrocarbons(PAHs),the Biolog method was employed to evaluate response of soil microbial communities in a roadside mulberry garden to PAHs pollution in functional diversity.Results show that PAHs pollution of the soil varied in degree,showing an order of Section 2(located between Sections 1 and 3)>Section 3(farthest from the highway)>Section 1(closest to the highway).Biolog analysis indicates that the three sections followed the order of 2>3>1 in average well color development(AWCD) of carbon utilization of soil microbes.Section 2 was the highest in Shannon index and Gini index and significantly higher than Sections 1 and 3,while in Shannon evenness Section 1 was significantly lower than Sections 2 and 3.Section 2 was the highest in soil microbial activity and abundance of microbial community structure and followed by Sections 3 and 1.Principal component analysis shows that the differences in physiological function of the soil microbial community were sharp between the sections,and embodied mainly in metabolism of carbohydrates and amino acids.Redundancy analysis reveals that soil microbes in Section 2 was the most closely related to PAHs pollution,indicating that higher PAHs concentration is more likely to stimulate physiological activities of the soil microbes in the mulberry garden and also their metabolism function to some extent.