Niu 16s Raw sequence reads. Niu 16s

The slightly polluted source water was pretreated in an integrated vertical-flow constructed wetland microcosm combined with a down-flow CW and an up-flow CW in Haining Second Water Plant, Zhejiang, China. The objective of this research was to examine nitrogen removal and the dynamics of the bacterial community during wetland microcosms treating water for about 7 months under high loading rate. The results showed that the average total nitrogen removal rates varied in different periods and had similar changing trend with the ambient temperature. Illumina highthroughput sequencing of 16S rRNA genes used to profile the bacterial community structure and diversity revealed that the phyla Proteobacteria, Bacteroidetes and Verrucomicrobia had a dominant presence in all sampling time. Additionally, the dominant AOB was a Nitrosomonas-like unknown genus belongs to Nitrosomonadaceae which was further proved by AOB clone library analysis. And more sequences belong to AOB than NOB. Quantitative analysis of nitrification and denitrification genes (amoA, nirS) revealed the variation of denitrifying with ambient temperature and the relative high amount AOB for the sustaining of relatively higher ammonia removal.