基于微生物群落特征解析的生物活性炭氨氧化机制

Ammonia oxidation mechanism of biological activated carbon based on analysis of microbial community characteristics

针对水源中氨氮微污染顽疾,从微生物群落特征(多样性、丰度)的角度探究了饮用水深度处理工艺生物活性炭(BAC)的氨氧化机制.结果表明:BAC上的微生物(细菌、古菌)群落结构与其所处滤池水样中的微生物群落结构差异显著,且其多样性高于水体.此外,BAC上具有硝化功能的微生物以古菌为主(占总古菌的77.72%),而水样中细菌和古菌的硝化功能均不显著.对BAC上功能微生物——氨氧化古菌(ammonia-oxidizing archaea,AOA)和细菌(ammonia-oxidizing bacteria,AOB)的分子生物学的研究结果表明,其数量分别为(49.10±4.45)×10^(5)个·g^(-1)(干重)和(23.20±2.55)×10^(4)个·g^(-1)(干重),AOA的数量显著多于AOB(P<0.01).运用T-RFLP对氨氧化微生物群落多样性进行的分析发现,BAC上和水体中的氨氧化微生物组成及优势菌种均不同,表明氨氧化微生物在BAC上的富集具有选择性.

In order to reduce source water pollution caused by ammonia and nitrogen derived from agricultural activities,biological active carbon(BAC)was proposed to applied to advanced drinking water purification.The ammonia oxidation mechanism of BAC was analyzed based on the structural diversity and abundance of microorganisms(bacteria and archaea).The results showed that the structural diversity of microbial community varied significantly between BAC-treated water and the original filtered water,which was more diversified in BAC-treated water.Archaea played a leading role in the nitrification process of BAC-treated water,accounting for 77.72%of the microorganism that underwent nitrification.Nitrification was overall insignificant in the original filtered water.The abundance of ammonia-oxidizing archaea(49.10±4.45)×10^(5) copies·g^(-1))was significantly higher than that of ammonia-oxidizing bacteria(23.20±2.55)×10^(4) copies·g^(-1))in the BAC-treated water(P<0.01).T-RFLP analysis on the structural diversity of ammonia oxidizing microbes further confirmed that both community structure and dominant species of ammonia oxidizing microorganisms were different between BAC and filter water,indicating the preference of ammonia-oxidizing microorganisms for BAC.