Abstract：
Lakes serve as heterogeneous ecosystems with rich microbiota. Although previous studies on bacterioplankton have advanced our understanding, there are gaps in our knowledge concerning variations in the taxonomic composition and community assembly processes of bacterioplankton across different environment conditions. This study explored the spatial dynamics, assembly processes, and co-occurrence relationships among bacterioplankton communities in 35 surface water samples collected from Hulun Lake (a grassland-type lake), Wuliangsuhai Lake (an irrigated agricultural recession type lake), and Daihai Lake (an inland lake with mixed farming and grazing) in the Inner Mongolia Plateau, China. The results indicated a significant geographical distance decay pattern, with biomarkers (Proteobacteria and Bacteroidota) exhibiting differences in the contributions of different bacteria branches to the lakes. The relative abundance of Proteobacteria (42.23%) were high in Hulun Lake and Wuliangsuhai Lake. Despite Actinobacteriota was most dominant, Firmicutes accounted for approximately 17.07% in Daihai Lake, suggested the potential detection of anthropogenic impacts on bacteria within the agro-pastoral inland lake. Lake heterogeneity caused bacterioplankton responses to phosphorus, chlorophyll a, and salinity in Hulun Lake, Wuliangsuhai Lake, and Daihai Lake. Although bacterioplankton community assembly processes in irrigated agricultural recession type lake were more affected by dispersal limitation than those in grassland-type lake and inland lake with mixed farming and grazing (approximately 52.7% in Hulun Lake), dispersal limitation and undominated processes were key modes of bacterioplankton community assembly in three lakes. This suggested stochastic processes exerted a greater impact on bacterioplankton community assembly in a typical Inner Mongolia Lake than deterministic processes. Overall, the bacterioplankton communities displayed the potential for collaboration, with lowest connectivity observed in irrigated agricultural recession type lake, which reflected the complex dynamic patterns of aquatic bacteria in typical Inner Mongolia Plateau lakes. These findings enhanced our understanding of the interspecific relationships and assembly processes among microorganisms in lakes with distinct habitats.
摘要：
湖泊是具有丰富微生物群的异质生态系统。尽管以前对浮游细菌的研究提高了我们的认识，在不同环境条件下浮游细菌的分类组成和群落组装过程的变化方面，我们的知识存在差距。本研究探索了空间动力学，装配过程，呼伦湖（草原型湖泊）采集的35个地表水样品中浮游细菌群落之间的共生关系，乌梁素海(灌溉农业衰退型湖泊)，和内蒙古高原的代海湖（一个农牧混合的内陆湖），中国。结果表明了显著的地理距离衰减模式，生物标志物（变形杆菌和拟杆菌）在不同细菌分支对湖泊的贡献方面表现出差异。呼伦湖和乌梁素海的变形杆菌相对丰度较高（42.23％）。尽管放线菌是最主要的，戴海湖中的Firmicutes约占17.07%，建议检测人为对农牧内陆湖泊内细菌的影响。湖泊异质性导致浮游细菌对磷的响应，叶绿素a,呼伦湖的盐度，乌梁素海,和黛海湖。尽管灌溉农业衰退型湖泊中的浮游细菌群落聚集过程受扩散限制的影响大于草地型湖泊和农牧混合的内陆湖泊（呼伦湖约为52.7％），分散限制和非支配过程是三个湖泊浮游细菌群落聚集的关键模式。这表明随机过程对典型内蒙古湖泊浮游细菌群落组装的影响大于确定性过程。总的来说,浮游细菌群落显示出合作的潜力，在灌溉农业衰退型湖泊中观察到的连通性最低，反映了典型内蒙古高原湖泊水生细菌的复杂动态规律。这些发现增强了我们对具有不同栖息地的湖泊中微生物之间的种间关系和组装过程的理解。
