芘污染盐碱土壤微生物-电动修复效率影响因素

以芘污染盐碱土壤为供试土壤，采用高通量测序技术对微生物-电动联合修复（BIO-EK）芘的过程中微生物群落结构进行了监测，结合芘浓度和微环境变化特征，分析了BIO-EK修复过程中微生物群落结构与污染物浓度和土壤微环境变化之间的相关性.结果表明，91d后BIO-EK中芘浓度由288.03mg/kg降至73.40mg/kg，而微生物修复（BIO）和电动修复（EK）使芘浓度分别降至114.23，150.27mg/kg.芘的降解速率在前期较大，随着处理时间的延长则逐渐降低.同时，电场的施加使一些土壤环境因子（温度、湿度和pH值）和微生物群落结构发生了明显变化.典型对应分析（CCA）表明，对微生物群落结构影响最大的因素为土壤pH值，其次为芘浓度和土壤温度，而微生物群落结构变化又是导致芘不能持续高效降解的重要原因.因而，通过调节土壤微环境、构建高效降解菌群等方式对BIO-EK修复过程进行调控，有望达到持续高效降解污染物的目的.

Factors affecting bio-electrokinetic remediation efficiency of pyrene contaminated saline-alkali soil

Using pyrene-contaminated saline-alkali soil as the test soil, the microbial community structure in the process of bio-electrokinetic remediation (BIO-EK) of pyrene was monitored by high-throughput sequencing technology, combined with the variation characteristics of pyrene concentration and microenvironment, the correlation among microbial community structure, pollutant concentration and soil microenvironment during BIO-EK remediation was analyzed. The results showed that the pyrene concentration in BIO-EK decreased from 288.03 mg/kg to 73.40 mg/kg after 91 days, while the bioremediation (BIO) and electrokinetics (EK) reduced the concentration of pyrene to 114.23 and 150.27 mg/kg, respectively. The degradation rate of pyrene was higher in the early stage, but gradually decreased with the extension of the treatment time. Meanwhile, the application of electric field caused obvious changes in some soil environmental factors (temperature, moisture content and pH) and microbial community structure, and the change of microbial community structure was the main reason that pyrene could not be degraded continuously and efficiently. Therefore, BIO-EK remediation process could be controlled by regulating soil microenvironment and constructing high-efficiency degrading bacteria, which is expected to achieve the aim of continuous and efficient degradation of pollutants.