Community Structure and Influencing Factors of Bacterioplankton in Spring in Zhushan Bay, Lake Taihu

Abstract

In order to investigate the characteristics of bacterioplankton in the spring in Zhushan Bay, Lake Taihu, the 16S rRNA gene of the bacterioplankton at four sampling sites in Zhushan Bay was sequenced by high-throughput sequencing using water samples collected from Yapugang, Shatanggang, Zhushanhunan, and Jiaoshan. The results showed that the coverage of the sequencing library was very high and could accurately represent the bacterioplankton community in the samples. The species richness of Jiaoshan was the highest, but the species evenness was lower. Cyanobacteria, Actinobacteria, Proteobacteria, and Bacteroidetes were the dominant phylum in Zhushan Bay. The average abundance of Cyanobacteria was as high as 64.73%, which indicated an outbreak of cyanobacteria bloom in the water. At the genus level, Anabaena, hgcI_clade, CL 500-29 _marine_group, Microcystis, Synechococcus, and Mycobacterium were predominant. The results of redundancy analysis (RDA) for the relationship between bacterioplankton and environmental factors showed that water temperature, chlorophyll a (Chl-a), ammonia nitrogen(NH4+-N), dissolved oxygen (DO), and phosphate (PO43--P)were the main environmental factors affecting the bacterioplankton community. Dissolved oxygen could significantly affect Microcystis; nutrient and water temperature also had an effect.