地球化学特征对太湖底泥中多氯联苯微生物厌氧脱氯的影响研究

项目名称： 地球化学特征对太湖底泥中多氯联苯微生物厌氧脱氯的影响研究

项目编号： No.41301546

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 许妍

作者单位： 东南大学

项目金额： 25万元

中文摘要： 多氯联苯是一种典型的持久性有机污染物，其在环境中的转化归趋倍受关注。底泥中多氯联苯可以通过微生物脱氯降解，但该脱氯方式所受的地球化学影响调控机制尚不明晰。本项目将选取太湖底泥为研究对象，考察微环境中外加电子受体SO42- （硫酸根）和FeOOH（以及碳源乙酸等地球化学特征对多氯联苯脱氯降解的影响，通过检测底泥中的多氯联苯单体变化深入探讨不同地球化学特征下多氯联苯脱氯速率、效率和路径的变化规律。通过研究脱氯过程中总细菌、 PCB脱氯细菌及关键脱卤酶基因的变化规律，结合多氯联苯脱氯特征，筛选出脱氯指示微生物/基因，揭示太湖底泥多氯联苯脱氯降解的地球化学影响调控机制，为监测自然衰减法修复多氯联苯污染底泥提供科学依据。

中文关键词： 多氯联苯；微生物降解；底泥；脱氯；基因

英文摘要： Polychlorinated biphenyls (PCBs) are typical persistent organic pollutants. Their fate in the environment is of great concern. Despite microbial-catalyzed reductive dechlorination is believed to take place in natural sediments, little is known about the influence of geochemical properties on PCB dechlorination activities. To overcome this obstacle, sediments collected from Taihu Lake, China, and a carefully selected PCB mixture will be used for this PCB dechlorination study. Sediment microcosms will be prepared with 50 ml serum bottles. Each sediment microcosm contains PCB-spiked dry sediment substrate, reduced anaerobic mineral medium (RAMM) medium and wet sediment inoculum. SO42- or FeOOH will be amended to selected microcosms to mimic different geochemical conditions. After around 6 months of incubation, supplemental carbon and energy source, acetate, will be added to some sediment microcosms. Periodic samplings will be performed within one year of incubation. Gas chromatography coupled with micro-electron capture detector (GC-μECD) based PCB congener-specific analysis will be applied to track the shifts PCB dechlorination rate, extent and pathways in conjunction with geochemical condition change. A molecular biology tool-quantitative polymerase chain reaction (qPCR), will be utilized to estimate 16S rRNA gen

英文关键词： Polychlorinated Biphenyls；Microbial Degradation；Sediment；Dechlorination；Gene