Diversity and Structure of Vegetation Rhizosphere Bacterial Community in Various Habitats of Liaohekou Coastal Wetlands

Abstract

Coastal wetlands are a type of unique ecosystem, in which rhizosphere microorganisms of vegetation play a significant role in the overall ecology. Rhizosphere soil samples from the vegetation of Liaohekou Coastal Wetlands, Northeast China (40°54′44″ N, 121°47′51″ E), were collected in seven habitats (Suaeda and Phragmites community in different coverage, aquaculture ponds and farmland biotopes) to evaluate the diversity and structure of bacterial community using high throughput sequencing. Soil physicochemical characteristics and bacterial communities were found to be affected by vegetation coverage by ANOVA tests. As and Ni were the main heavy metal variables affecting the bacterial communities as demonstrated by RDA tests, while NO3−-N were important variables in nutrient factors. Proteobacteria was the predominant phylum in all soils. Gillisia and Woeseia were the two most dominant genera peculiarly in Suaeda and Phragmites community. Meanwhile SparCC showed that Woeseia play a dominant role in wetland rhizosphere bacterial communities. The Chemoheterotrophic function was dominant in all communities with FAPROTAX results, while in wetland the cycle of Sulfur and Nitrogen were significantly affected by vegetation type and coverage. In conclusion, this study revealed the structural composition and diversity of rhizosphere bacterial communities under different vegetation types and coverage. This research could help deepen our understanding of the microbial ecology on the wetlands and provide information on bacterial communities in various habitats.