[Structure and diversity of -type denitrifying microbial community in marsh soils at different invasion stages of in the Minjiang River estuary, China].

To explore the differences in structure and diversity of -type denitrifying microbial community in marsh soils at different invasion stages of , the mudflat (MF, before invasion) and the marsh after seaward invasion for 1-2 years (SAN) and 6-7 years (SA) in Shanyutan of the Minjiang River estuary were investigated by high-through put sequencing method. Results showed that the seaward invasion of reduced the richness and diversity of -type denitrifying microbial community in marsh soils. The -type denitrifying microbial community in soils at different invasion stages included Proteobacteria and Actinobacteria, with Proteobacteria as the dominant one. The seaward invasion of greatly altered the composition of -type denitrifying microbial community in marsh soils. The highest relative abundance of genus in soils from different invasion stages were , and , respectively. The seaward invasion of increased the spatial heterogeneity of -type denitrifying microbial community composition in marsh soils. In SAN plot, the enhancement of spatial heterogeneity was primarily due to higher environmental disturbances in plots and the increased spatial heterogeneity of environmental variables caused by the seaward invasion of . The seaward invasion of altered the physico-chemical properties (, grain composition, pH and moisture) and N nutrient conditions (total N, NH-N and NO-N) in marsh soils, which greatly altered the structure and diversity of -type denitrifying microbial community. Our findings reveal the microbial mechanism of denitrification process in marsh soils during the seaward invasion of .