Abstract：
Over the last six decades, northwest China has undergone a significant climatic shift from \"warm-dry\" to \"warm-wet\", profoundly impacting the structures and functions of lake ecosystem across the region. However, the influences of this climatic transition on the diversity patterns, co-occurrence network, and assembly processes of eukaryotic microbial communities in lake ecosystem, along with the underlying mechanisms, remain largely unexplored. To bridge this knowledge gap, our study focused on Lake Bosten, the largest inland freshwater body in China, conducting a comprehensive analysis. Firstly, we examined the dynamics of key water quality parameters in the lake based on long-term monitoring data (1992-2022). Subsequently, we collected 93 water samples spanning two distinctive periods: low water level (WL) and high total dissolved solids (TDS) (PerWLTDS; 2010-2011; attributed to \"warm-dry\" climate), and high WL and low TDS (PerTDSWL; 2021-2022; associated with \"warm-wet\" climate). Eukaryotic microorganisms were further investigated using 18S rRNA gene sequencing and various statistical methods. Our findings revealed that climatic warming and wetting significantly increased eukaryotic microbial α-diversity (all Wilcox. test: P<0.05), while simultaneously reducing β-diversity (all Wilcox. test: P<0.001) and network complexity. Through the two sampling periods, assembly mechanisms of eukaryotic microorganisms were predominantly influenced by dispersal limitation (DL) and drift (DR) within stochastic processes, alongside homogeneous selection (HoS) within deterministic processes. WL played a mediating role in eukaryotic microbial DL and HoS processes in the PerTDSWL, whereas water quality and α-diversity influenced the DL process in the PerWLTDS. Collectively, these results underscore the direct and indirect impacts of \"warm-wet\" conditions on the eukaryotic microorganisms within Lake Bosten. This study provides valuable insights into the evolutionary dynamics of lake ecosystems under such climatic conditions and aids in predicting the ecological ramifications of global climatic changes.
摘要：
在过去的六十年里，中国西北地区经历了从“温暖干燥”到“温暖潮湿”的重大气候转变，深刻影响了整个地区湖泊生态系统的结构和功能。然而,这种气候变化对多样性模式的影响，共现网络，和湖泊生态系统中真核微生物群落的组装过程，以及潜在的机制，在很大程度上仍未被探索。为了弥合这种知识差距，我们的研究集中在博斯腾湖，中国最大的内陆淡水水体，进行全面分析。首先,我们根据长期监测数据（1992-2022年）检查了湖泊中关键水质参数的动态。随后，我们收集了93个水样，跨越两个不同的时期：低水位（WL）和高总溶解固体（TDS）（PerWLTDS；2010-2011；归因于“温暖-干燥”气候），以及高WL和低TDS（PerTDSWL；2021-2022年；与“暖湿”气候相关）。使用18SrRNA基因测序和各种统计方法进一步研究了真核微生物。我们的发现表明，气候变暖和湿润显着增加了真核微生物α-多样性（所有Wilcox。试验：P<0.05），同时降低β-多样性(所有Wilcox。测试：P<0.001)和网络复杂性。通过两个采样周期，真核微生物的组装机制主要受随机过程中的分散限制（DL）和漂移（DR）的影响，与确定性过程中的同质选择(HoS)一起。WL在PerTDSWL的真核微生物DL和HoS过程中起中介作用，而水质和α-多样性影响了PerWLTDS中的DL过程。总的来说，这些结果强调了“温湿”条件对博斯腾湖内真核微生物的直接和间接影响。这项研究为在这种气候条件下湖泊生态系统的进化动态提供了宝贵的见解，并有助于预测全球气候变化的生态后果。
