中文摘要：

自然生态系统中厌氧氨氧化菌和氨氧化古菌的发现,改变了人们对传统氮循环过程的认识.通过氨氧化古菌和厌氧氨氧化菌在缺氧/厌氧的条件下完成硝化反应和封闭的氮循环,对于河流氮循环生态修复意义显著.通过PCR聚合酶链反应结合水体沉积物理化指标,研究典型河流湿地中厌氧氨氧化菌和氨氧化古菌及其在循环中的作用.结果表明,在海河支流北运河湿地中存在厌氧氨氧化菌和氨氧化古菌,它们对于水体和底泥沉积物的氮转化有较重要作用.通过构建16S rRNA克隆文库生物多样性分析比较,发现湿地中厌氧氨氧化菌的生物多样性相对较低,96个克隆序列只分为3个OTUs;其与基因库（GenBank）中已探明的厌氧氨氧化菌Candidatus＂Kuenenia stuttgartiensis＂和Candidatus＂Brocadia fulgida＂的相似度分别为98%和95%.通过建立氨氧化古菌克隆文库发现,96个克隆子共得到5个OTUs,其与GenBank中关系最近序列（土壤/沉积物中）的相似度均大于95%;对本实验样本和水相、土壤/沉积物相中不同氨氧化古菌进行进化谱系分析,发现北运河河流湿地的古菌amoA基因属于土壤/沉积物进化分支.

英文摘要：

With the discoveries of anaerobic ammonium oxidizing bacteria（anammox）and ammonia oxidizing archaea in natural ecosystems,the conventional understanding of the microbial nitrogen cycle has been changed.How to fulfill crenarchaeal nitrification and anammox under anoxic/anaerobic circumstances is significant to the ecological remediation of rivers.In order to detect and analyze the population diversities of anammox bacteria and ammonia-oxidizing archaea（AOA）in typical river wetland ecosystems and their potential role in the nitrogen cycle,PCR was combined with physical-chemical analysis on water and sediment samples of the North Canal riparian wetland.Anammox bacteria were detected using anammox and planctomycete-specific 16S rRNA gene primers while AOA were identified by the archaeal amoA functional gene in the riparian wetland.Chemical analysis of water and sediments showed that anammox bacteria and AOA have an active effect on nitrogen pollution remediation compared with other site samples.Through analysis and comparison of 16S rRNA gene clone libraries,we found that the biodiversity of anammox bacteria in North Canal sediments was low：96 sequences of anammox bacteria were assigned to 3 Operational Taxonomic Units（OTUs）,and the similarities with the known anaerobic ammonia oxidation bacteria,Candidatus ＂Kuenenia stuttgartiensis＂ and Candidatus ＂Brocadia fulgida＂,were 98% and 95% respectively.All 96 determined sequences of AOA were assigned into 5 OTUs,and the similarities with the closest relatives（soil/sediment group）in GenBank were all higher than 95%.The phylogenetic affiliation showed that AOA sequences of North Canal riparian wetland affiliate to soil/sediment filiations.