污水人工快速渗滤系统中氨氧化菌16S rDNA的DGGE分析

DGGE Analysis of 16S rDNA for Ammonium Oxidizing Bacteria in Constructed Rapid Infiltrition System(CRI)

为了研究污水人工快速渗滤系统（CRI）中氨氧化菌的空间分布规律以及NH4-N在CRI中的迁移转化机理，从深圳运行中的CRI系统砂层填料中以5～10cm间隔垂直取12个样品，对其氨氧化菌的16SrDNA进行DGGE分析。结果表明，CRI系统中氨氧化菌菌群随着深度的增加先增多后减少，在表层至10cm处氨氧化菌约有4-5种组成，主要由某些以有机氮为降解底物的微生物和进水中被砂粒介质截流吸附的微生物组成；在20-90cm范围内氨氧化菌增加至9种左右，多样性最为丰富，是亚硝化作用发生的主要区域；而在100cm以下的范围，由于NH4-N浓度的降低或系统复氧不足，氨氧化菌迅速减少至5～6种。该研究结果证明了氨氧化菌在快渗池内分布范围的变化对NH4-N去除率的影响，即氨氧化菌在快渗池内分布的越接近中上层，对NH4-N的去除效果越好。关于CRI系统中氨氧化菌的空间分布规律及其与NH4-N去除率关系的认识，为工艺改进和效果提高提供了理论基础。

In order to reveal the microbial community distribution of ammonium oxidizing bacteria and the removal mechanism of NH4-N in constructed rapid infiltrition system （CRI）, sands of different depths were sampled from CRI in Shenzhen, and were analyzed by denaturing gradient gel electrophoresis （DGGE）. The profiles of DGGE show that the microbial community of ammonium oxidizing bacteria increases followed by a decrease from top to bottom. There are about 4-5 species in the upper 10 cm part, and they are composed of microorganisms in sewage or those who played important roles in the biodegradation of organonitrogen. About 9 species are found in CRI between 20 cm and 90 cm in depth, where the nitrosation capacity is stronger. For lack of NH4-N or oxygen, the species of ammonium oxidizing bacteria reduce to 5-6 at the depth below 100 cm. The results will be that, the upper level the ammonium oxidizing bacteria distribute in CRI, the higher the removal rate of NH4-N. The relationship between community distribution of ammonium oxidizing bacteria and the removal rate of NH4-N is meaningful to improve the treatment performance of CRI.