Li Xinghao, Stegen James C, Yu Yuhe, Huang Jie
Hubei Key Laboratory of Regional Development and Environmental Response, Hubei Engineering Research Center for Rural Drinking Water Safety, Hubei University, Wuhan, China.
Donghu Experimental Station of Lake Ecosystems, Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
Front Microbiol. 2023 Jun 2;14:1166322. doi: 10.3389/fmicb.2023.1166322. eCollection 2023.
Setting the pace of life and constraining the role of members in food webs, body size can affect the structure and dynamics of communities across multiple scales of biological organization (e.g., from the individual to the ecosystem). However, its effects on shaping microbial communities, as well as underlying assembly processes, remain poorly known. Here, we analyzed microbial diversity in the largest urban lake in China and disentangled the ecological processes governing microbial eukaryotes and prokaryotes using 16S and 18S amplicon sequencing. We found that pico/nano-eukaryotes (0.22-20 μm) and micro-eukaryotes (20-200 μm) showed significant differences in terms of both community composition and assembly processes even though they were characterized by similar phylotype diversity. We also found scale dependencies whereby micro-eukaryotes were strongly governed by environmental selection at the local scale and dispersal limitation at the regional scale. Interestingly, it was the micro-eukaryotes, rather than the pico/nano-eukaryotes, that shared similar distribution and community assembly patterns with the prokaryotes. This indicated that assembly processes of eukaryotes may be coupled or decoupled from prokaryotes' assembly processes based on eukaryote cell size. While the results support the important influence of cell size, there may be other factors leading to different levels of assembly process coupling across size classes. Additional studies are needed to quantitatively parse the influence of cell size versus other factors as drivers of coordinated and divergent community assembly processes across microbial groups. Regardless of the governing mechanisms, our results show that there are clear patterns in how assembly processes are coupled across sub-communities defined by cell size. These size-structured patterns could be used to help predict shifts in microbial food webs in response to future disturbance.
身体大小设定了生命的节奏并限制了食物网中成员的作用，它能够在生物组织的多个尺度（例如从个体到生态系统）上影响群落的结构和动态。然而，其对塑造微生物群落以及潜在组装过程的影响仍知之甚少。在此，我们分析了中国最大城市湖泊中的微生物多样性，并使用16S和18S扩增子测序解析了控制微生物真核生物和原核生物的生态过程。我们发现，尽管微微型/微型真核生物（0.22 - 20μm）和微型真核生物（20 - 200μm）具有相似的系统发育型多样性，但它们在群落组成和组装过程方面存在显著差异。我们还发现了尺度依赖性，即微型真核生物在局部尺度上受环境选择强烈影响，在区域尺度上受扩散限制影响。有趣的是，与原核生物具有相似分布和群落组装模式的是微型真核生物，而非微微型/微型真核生物。这表明真核生物的组装过程可能基于真核生物细胞大小与原核生物的组装过程耦合或解耦。虽然结果支持细胞大小的重要影响，但可能还有其他因素导致不同大小类别的组装过程耦合程度不同。需要进一步研究来定量解析细胞大小与其他因素作为驱动微生物群落协调和不同组装过程的影响。无论控制机制如何，我们的结果表明，在由细胞大小定义的子群落之间，组装过程的耦合方式存在明显模式。这些大小结构模式可用于帮助预测微生物食物网对未来干扰的响应变化。
