常温下CANON反应器中功能微生物的沿程分布

Distribution of functional bacteria alone bio-filter of CANON reactor at room temperature

摘要:

为研究常温环境中上向流曝气生物滤池型CANON反应器中功能微生物的沿程分布特点,采用扫描电镜对微生物形态进行观测,并基于amoA以及16S rDNA片段的多样性,采用聚合酶链式反应-变性梯度凝胶电泳分析技术（PCR-DGGE）对滤层不同高度的功能微生物进行群落结构分析,通过分子克隆法进行种属鉴定及系统发育分析．结果表明:反应器内微生物形态多样,其中优势菌为0.2～1.0 μm的球形及椭球形菌;滤层500 mm以下的氨氧化细菌种类和数量远远高于滤层上半部分,而厌氧氨氧化菌种类单一,其数量沿滤层自上而下有增强的趋势;反应器中检测到的氨氧化细菌为亚硝化球菌属(Nitrosococcus)和亚硝化单胞菌属(Nitrosomonas),而厌氧氨氧化菌与Candidatus Kuenenia stuttgariensis的相似度高达98％．基于功能微生物的种属特征及沿程分布特点,可以有针对性地改善功能分区,改变滤料材质,从而增强反应器的脱氮效果及抗冲击能力．

Abstract:

The distribution of functional bacteria alone the bio-filter of a up-flow biological aerated CANON reactor was investigated using PCR-DGGE techniques based on the diversity of amoA and 16S rDNA fragments and the identification and phylogeny were performed by molecular clone methods. Besides, the morphology was observed using scan electron microscope (SEM) in this study. The SEM photographs indicated a diverse morphology, of which spherical and elliptical (0.2-1.0 μm) were predominant. The PCR-DGGE results indicated a much better diversity and bigger population of ammonia oxidizing bacteria under a depth of 500 mm, while ANAMMOX bacteria showed a low diversity and the population increased in some degree from top to bottom along the filter. Phylogenetic analysis indicated that Nitrosococcus and Nitrosomonas related ammonia oxidizing bacteria and Candidatus Kuenenia stuttgariensis like ANAMMOX bacteria existed in the reactor. Based on the species traits and the distribution of functional bacteria along the filter, some strategies should be made to improve the partition function and change the filter material, aiming at enhancing nitrogen removal and impact resistance of the reactor.