好氧颗粒污泥和活性污泥细菌种群结构对五氯酚污染的响应研究

应用一种新的微生物分子生态学方法--末端限制性片段长度多态性(T-RFLP)法研究了好氧颗粒污泥和活性污泥在毒性化合物五氯酚(PCP)影响下的废水处理性能及其微生物种群结构的响应.结果表明,PCP浓度为30 mg·L-1时,颗粒污泥和活性污泥的COD去除率为38%、77%,与10～20 mg·L-1 PCP相比,分别下降了56%和15%.另外,PCP浓度为20 mg·L-1时,去除率为13%和58%,与10～20 mg·L-1 PCP相比,分别下降了86%和40%,说明PCP对氨氮去除率的影响大于对COD去除率的影响,对颗粒污泥的影响大于对活性污泥的影响.PCP对好氧颗粒污泥和活性污泥的细菌种群结构都产生了明显的影响,而且好氧颗粒污泥的变化程度大于活性污泥;PCP浓度为30 mg·L-1时,好氧颗粒污泥中的细菌种群数量明显下降,TRFs片段数从26下降到14,但活性污泥中的细菌种群数量基本不变,污泥中细菌种群结构的变化趋势与污泥的水处理性能的变化趋势相一致.

The response of bacterial community within aerobic granular sludge and activated sludge to pentachlorophenol contamination

The performance of aerobic granular sludge for the treatment of wastewater was studied. The response of the bacterial community to different concentrations of Pentachlorophenol (PCP) was monitored by terminal restriction fragment length polymorphism (T-RFLP) technique. When PCP concentration was 30 mg·L^-1, COD removal rates of the aerobic granular sludge and activated sludge were 38% and 77%, which decreased by 56% and 15%, respectively. In addition, uhe ammonia removal rates of the aerobic granular sludge and activated sludge were 13% and 58%, which decreased by 86% and 40%, respectively. These data indicated that the impact of PCP on the aerobic granular sludge was stronger than that of activated sludge and the influence on removal of ammonia nitrogen was stronger than that of COD removal. The results of the T-RFLP analysis showed that the change of bacterial community within the aerobic sludge was more apparent than that of activated sludge. When PCP was 30 mg·L^-1, the number of Terminal Restriction Fragments (TRFs) decreased from²6 to 14 in aerobic granular sludge but maintained stable in activated sludge. It is suggested that the bacterial species number within the aerobic granular sludge decreased but that in activated sludge kept stable. The change trend of the bacterial diversity was consistent with the performance of the wastewater treatment.