Bacterioplankton play critical roles in biogeochemical cycling. Although spatial and temporal variations in bacterioplankton community compositions (BCCs) within individual habitat have been reported, knowledge gaps remain for studies conducted within different habitats. In this work, we examined the seasonal and spatial variability of BCCs in Nanfei River and Lake Chaohu which had significant environmental heterogeneity using a high-throughput sequencing technique of 16S rRNA gene amplicons. The results showed that spatial variation has a more obvious impact on the BCCs than seasonal changes. The microbial diversity gradually decreased and BCCs changed obviously along water flow direction from Nanfei River to the western and estern parts of Lake Chaohu over all seasons. LEfSe analysis showed that Nanfei River had higer abundance of species belonging to the orders Rhodocyclales, Methylococcales, Campylobacterales and Flavobacteriales, samples from eastern part of Lake Chaohu were abundant in taxonomies including the order Rickettsiales, while the western part had high abundance of taxonomies belonging to the order Chroococcales. The redundancy analysis (RDA) indicated that BCCs in Nanfei River were associated with high nutrient (TP, PO₄-P, TN, NH₃-N, NO₂-N and NO₃-N) concentrations and electrical conductivity. Variance partitioning RDA analysis indicated that the combined effects of all variables may be most important affecting BCCs. This study may provide a framework for modeling the change in bacterioplankton communities through different habitats from a river to lake.

浮游细菌在生物地球化学循环中起关键作用。尽管已报告了单个生境中浮游植物群落组成（BCC）的时空变化，但在不同生境中进行的研究仍存在知识空白。在这项工作中，我们使用16S rRNA基因扩增子的高通量测序技术研究了南飞河和巢湖中具有显着环境异质性的BCC的季节和空间变异性。结果表明，空间变化对BCC的影响比季节变化更为明显。从南飞河到巢湖西部和酯类部分，水体微生物多样性在整个季节逐渐降低，BCCs变化明显。Rhodocyclales，Methylococcales，Campylobacterales和Flavobacteriales，巢湖东部样品在分类包括订单充裕立克次氏体，而西部部分有高丰属于顺序分类的Chroococcales。冗余度分析（RDA）表明，南fei河的BCCs与高养分（TP，PO ₄ -P，TN，NH ₃ -N，NO ₂ -N和NO _{3）有关。}-N）浓度和电导率。方差划分RDA分析表明，所有变量的综合影响可能是影响BCC的最重要因素。这项研究可能提供一个框架，用于模拟从河流到湖泊的不同生境中浮游细菌群落的变化。