外加营养源作用下砖红壤中五氯酚还原转化的生物化学作用机制  

Reduction transformation and biochemistry mechanisms of PCP in latosol under addition of exogenous nutrients

作　　者：陈曼佳[1,2,3] 刘承帅[2] 吴伟坚[1,2,3] 童辉[1,2,3] 李芳柏[2] 

机构地区：[1]中国科学院广州地球化学研究所,广东广州510640 [2]广东省农业环境综合治理重点实验室,广东省生态环境与土壤研究所,广东广州510650 [3]中国科学院大学,北京100039

出　　处：《生态环境学报》2013年第2期325-329,共5页Ecology and Environmental Sciences

基　　金：国家自然科学基金面上项目(40971149);广东省自然科学基金团队项目(S2011040001094);广东省自然科学基金项目(S2011010006107)

摘　　要：采用室内培养实验研究外加乳酸和蒽醌-2,6-磺酸钠等营养源条件下,玄武岩砖红壤中五氯酚的还原转化动力学与微生物群落结构变化。结果表明,玄武岩砖红壤中五氯酚的还原转化一级动力学常数为4.5×10 3d 1;添加乳酸或同时添加乳酸和AQDS,五氯酚的还原转化速率显著提高,其一级动力学常数分别为7.3×10 3d 1和14.3×10 3d 1。循环伏安试测结果表明,添加乳酸和AQDS促进了砖红壤中活性亚铁的生成,并显著降低体系的氧化半反应峰电位。末端限制性片段长度多态性分析结果表明,添加五氯酚、乳酸和AQDS显著影响微生物群落结构,土壤微生物多样性显著下降;添加乳酸时,体系中微生物优势种群为梭菌,存在少量的具有铁还原能力的希瓦氏菌,未发现脱氯菌。因此,玄武岩砖红壤中五氯酚的还原转化主要是通过铁还原菌介导生成吸附态Fe(II)引起的活性亚铁还原脱氯机制。In this study, we investigated the reductive transformation of PCP and soil bacteria community structures in basalt latosol under addition of lactate and AQDS. Results showed that PCP reductive transformation occurred with k value of 4.5× 10-3d-1 in basalt latosoL The addition of lactate and AQDS led to the enhanced rates of PCP transformation with k value of 7.3×10-3 d-1 and 14.3 × 10-3d-1, respectively. Cyclic voltammetry test results showed that the addition of lactate and AQDS led to the enhanced rates of active Fe（ II ） species generation in basalt latosol and significantly enhance the reduction potential in the system. T-RFLP analysis results showed that the microbial communities were affected by the addition of PCP, lactate and AQDS and the microbial diversity was significantly decreased. Clostridum was the dominant population in the system after the addition of lactate. There were also small amounts of Shewanella which has iron-reducing ability but no decldorinating bacteria. Therefore, reductive transformation of PCP in basalt latosol occurs though chemical dechlorinating process, which induced by iron-reducing bacteria indirectly.

关 键 词：玄武岩砖红壤 五氯酚 还原转化 微生物群落结构 T-RFLP 

分 类 号：X131.3[环境科学与工程—环境科学]