佳乐麝香与镉复合污染对土壤微生物群落功能和丰度的影响

Joint effects of galaxolide and cadmium on soil microbial community function and abundance

为考察佳乐麝香(HHCB)和镉(Cd)复合污染对土壤微生物群落的影响,采用Biolog和q PCR技术对土壤微生物群落的功能多样性和丰度进行研究。研究发现,HHCB及其与Cd复合污染提高了土壤微生物对碳源的利用能力,6大类碳源利用中以对酯类利用效率最高,对糖类和羧酸类利用效率较低。HHCB污染下,Shannon、Simpson和Mc Intosh指数没有显著性变化,500、1000 mg·kg-1HHCB与Cd复合污染下三种指数显著提高。HHCB加入后,土壤微生物的种群丰富度提高,优势种群增加,种群间的均一性被打破。500、1000 mg·kg-1HHCB及其与Cd复合污染显著促进了细菌生长,HHCB污染显著抑制了放线菌生长。细菌的丰度随HHCB浓度的增加而增加,真菌和放线菌的丰度则随着HHCB浓度的增加而降低,放线菌受HHCB与Cd的影响比细菌和真菌更敏感。

In order to investigate the joint effects of galaxolide and cadmium on soil microbial community,soil microbial community function and abundance were studied by Biolog and q PCR methods in this paper. Results showed that the ability of utilizing carbon sources in soil microorganisms has been improved under HHCB and HHCB-Cd combined pollution, and the utilization efficiency of esters was the highest,while sugars and acids have lower utilization efficiency compared with others 6 kinds of carbon sources. There was no significant change in Shannon, Simpson and Mc Intosh indexes under HHCB pollution. While the indexes have significantly increased under the 500 and 1000mg·kg-1HHCB-Cd combined pollution.The species richness and the dominant population were significantly promoted, and the homogeneity of the population was broken after HHCB addition in the combined pollution soil. It significantly promoted the growth of bacteria under 500 and 1000 mg·kg-1HHCB-Cd combined pollution,respectively. While HHCB has significantly inhibited the growth of actinomycetes. The abundance of bacteria was increased as the increasing of HHCB concentrations. However, the abundance of fungi and actinomycetes were decreased as the increasing of HHCB concentrations. In this study, actinomycetes were more sensitive than bacteria and fungi to the joint effects of HHCB and Cd.