The authors probed Illumina high-throughput sequencing in Hanjiang River to investigate the community structure, distribution and assembly mechanisms of bacterioplankton integrally and rare taxa (RT), abundant taxa (AT) respectively. Hanjiang River bacteria spanned across 22 phyla, 55 classes, 93 orders, 132 families and 164 genera dominated by Proteobacteria, Actinobacteria and Bacteroidetes. 4035 ASVS (80.2%) were defined as RT. Significant seasonal differences were found of the bacteria community by alpha diversity and this pattern were intensified by RT. Non-metric multidimensional scaling (NMDS) showed insignificant differences of the seasonal and spatial distribution of bacteria community in Hanjiang River. Mantel tests considered dissolved oxygen (DO) and ammonia nitrogen as primary influencing factors of autumn microbiome community. Variance partitioning analysis (VPA) indicated more stress from environmental factors to the bacteria community compared with spatial factors. The holistic bacteria community was dominated by deterministic process, while both RT and AT were mainly affected by stochastic process. Overall, RT was mainly influenced by environmental selection as opposed to AT which were more inclined to stochastic distribution.

基于Illumina高通量测序, 调查汉江浮游细菌整体及稀有、丰富物种的组成、分布与构建机制, 得到细菌22门55纲93目132科164属, Proteobacteria, Actinobacteria和Bacteroidetes等为优势菌门。将4035个ASV (80.2%)定义为稀有物种。汉江浮游细菌群落α多样性季节差异显著, 而稀有物种受季节的影响更显著。非度量多维尺度分析结果显示, 汉江浮游细菌群落季节分布与沿程分布差异不显著。Mantel分析结果表明, 溶解氧和氨氮为秋季群落的主要影响因素。方差分解分析结果表明, 环境因子对群落的影响大于空间因子。确定性过程为群落总体的主导构建机制, 而稀有及丰富物种主要受随机过程影响。与丰富物种相比, 稀有物种受环境选择过程的影响更大。