Community Structure And Abundance Of Anammox Bacteria In Alpine Meadow,Tibetan Plateau

Anaerobic ammonium-oxidizing(anammox)bacteria is an important addition to the comprehensive understanding of nitrogen cycle,which is central links in global wetland nitrogen cycle.The study of anammox bacteria was mainly focused on ocean,inland lakes,paddy field and mangrove forest.However,no study has yet addressed on anammox bacteria from alpine meadow on the Tibetan Plateau.The presence,abundance,diversity of anammox bacteria and its correlation with environment factors in alpine meadow of the Tibetan Plateau were explored using the technology of clone library,real-time PCR and Mi-seq sequencing.The main results were described as the following:1.Anammox bacteria sequences were firstly detected in the alpine meadow of Tibetan Plateau,suggesting that anammox has important role in N cycle.The unique anammox bacterial sequences detected in Tibetan alpine meadow suggests the uniqueness of anammox bacterial physiology.2.In this region,three genuses of anammox bacteria were found,which included Brocadia,Kuenenia and Scalindua.Kuenenia were dominant in the anammox bacterial community in Gannan wetland.However,Brocadia were dominant in the anammox bacterial community in Tibetan alpine meadow.The proportion of Brocadia and Kuenenia were increased in the anammox bacterial community in alpine meadow,Gannan.Nevertheless,it was decreased in the anammox bacterial community of alpine steppe,which indicated that the anammox bacterial community was influenced by degeneration of alpine wetland.3,The number of anammox bacteria 16S rDNA in alpine swamp meadow soil of Tibetan Plateau was 105?107 copies/g,which was in line with previous reports.Anammox bacteria 16S rRNA gene abundance was significantly correlated with NH4+/NOx-.Besides,the number of anammox bacteria HzsA gene was significantly correlate with NH4+/NOx-,TN and TP in soil samples.4.The abundance of AOAwas generally higher than AOB,which showed that AOAplayed a major role in the process of supply substrate for anammox in Tibetan alpine meadow.