AUTHOR=Chen Zhao-Jin , Liu Yong-Qi , Li Yu-Ying , Lin Li-An , Zheng Bao-Hai , Ji Ming-Fei , Li B. Larry , Han Xue-Mei 

TITLE=The Seasonal Patterns, Ecological Function and Assembly Processes of Bacterioplankton Communities in the Danjiangkou Reservoir, China

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.884765

DOI=10.3389/fmicb.2022.884765

ISSN=1664-302X

ABSTRACT=As the water source for the Middle Route Project of the South-to-North Water Diversion Project (MR-SNWD) of China, the Danjiangkou Reservoir (DJR) is in the process of ecosystem reassembly, but the composition, function, and assembly mechanisms of the bacterioplankton communities in this ecosystem are not yet clear. In this study, the composition, distribution characteristics and influencing factors of these bacterioplankton communities were analyzed by high-throughput sequencing (HTS); PICRUSt2 was used to predict community function; a molecular ecological network was used to analyze bacterioplankton interactions; and the assembly process of bacterioplankton communities was estimated with a neutral model. The results indicate that the communities, function and interactions of bacterioplankton in the DJR had significant annual and seasonal variations and that the seasonal differences were greater than the annual differences. Excessive nitrogen (N) and phosphorus (P) nutrients in the DJR are the most important factors affecting the water quality in the reservoir, and N and P nutrients are the main factors affecting the bacterial communities. The season is the most important factor affecting the N and P cycling functions of bacterioplankton. Ecological network analysis indicated that the average clustering coefficient and average connectivity of the spring samples were lower than those of the autumn samples, while the number of modules for the spring samples was higher than that for the autumn samples. The neutral model explained 66.3%, 63.0%, 63.0%, and 70.9% of the variations in the bacterioplankton community for samples from the spring of 2018, the autumn of 2018, the spring of 2019, and the autumn of 2019, respectively. Stochastic processes dominate bacterioplankton community assembly in the DJR. This study, which revealed the composition, function, interactions, and assembly of bacterioplankton communities in the DJR, provides a reference for the protection of the water quality and ecological functions of bacterioplankton in the DJR.