贫营养条件下IAMBR污泥微生物群落结构的演变

采用PCR-DGGE技术并结合系统处理效果研究了贫营养条件下IAMBR污泥微生物群落结构,结果表明:IAMBR污泥中总细菌多样性特征、相似性特征和种群归属特征具有高度的协同性.运行前18天,氨氮去除率由95%降至73%后增加至82%,同时SVI值由123.7mL/g升至135.2mL/g再降至128.4mL/g.微生物群落在试验末期演替剧烈,总细菌相似性指数下降到63.6%,SVI值最终升至132.5mL/g.通过克隆测序分析,IAMBR系统中微生物菌种大部分为未培养菌种,其中亚硝化螺菌属占据优势地位,说明贫营养环境对IAMBR微生物群落产生不良影响,污泥微生物功能性指向明显,即硝化功能菌占据优势地位.

Analysis of IAMBR on succession of sludge microbial community composition in the oligotrophic condition

The microbial community in the IAMBR activated sludge grown in a oligotrophic condition was investigated with PCR-DGGE technology and the treatment effect of the IAMBR system was evaluated. The results showed that there was a high degree of cooperativity among the diversity, similarity and population belonging of the total bacteria. In the first 18days, the ammonia nitrogen removal dropped from 95% to 73%, and then increased to 82%. At the same time, the SVI increased from 123.7mL/g to 135.2mL/g, and then decreased to 128.4mL/g. Microbial community experienced a drastic succession at the end of experimental period. The similarity index of bacteria dropped to 63.6%, and the SVI increased to 132.5mL/g eventually. The cloning sequencing analysis revealed that the majority of bacteria in the IAMBR belonged to uncultured bacterium and the Nitrosospira held a dominant position. The research showed that oligotrophic condition had adverse effects on microbial community in the IAMBR. The sense of functional orientation of the microbial community was obvious and the nitrifying bacteria occupied a dominant position.