文章摘要：
The study aims to identify relations of denitrifying bacterial and fungal communities to nitrogen removals in vertical flflow wetland microcosms (VFWMs) using four macrophyte species (Iris pseudacorus,Canna glauca, Scirpus validus and Cyperus alternifolius) and three species richness levels (unplanted,monocultured and 4-species mixture) as fifixed factors. Results showed that among four macrophyte
species, only Canna glauca planting signifificantly decreased nitrate removal by 87.7% in the VFWMs. The 4-species mixture improved TN and nitrate removals by 84.0% and 91.3%, but decreased ammonium removal by 94.5%. Heatmap and nonmetric multidimensional scaling analyses identifified a signifificant difference in denitrifying bacterial community structure across macrophyte richness levels, but did not identify the difference in denitrifying fungal communities. The redundancy analysis revealed that denitrifying bacterial community individually explained 99.4% and 93.0% variance of nitrogen removals among four macrophyte species and across macrophyte richness levels, while the fungal community only explained 30.7% and 21.8% variance of nitrogen removals. Overall, the macrophyte richness and bacterial denitrififiers are the critical factors of nitrogen removals in the VFWMs, thus providing useful data to design a vertical flow constructed wetland at a full scale.