Abstract：
The bright coniferous forest area in the cold temperate zone of China is a terrestrial ecosystem primarily dominated by low mountain Larix gmelinii trees. Limited information is available regarding the assembly mechanisms and interactions of microbial communities in the soil in this region. This study employed high-throughput techniques to obtain DNA from myxomycetes, bacteria, and fungi in the soil, evaluated their diversity in conjunction with environmental factors, associated them with the assembly process, and explored the potential interaction relationships between these microorganisms. The findings of our study showed that environmental factors had a more significant influence on the α and β diversity of bacteria compared to myxomycetes and fungi. Microbial communities were influenced by environmental selection and geographical diffusion, although environmental selection appeared to have a more significant impact than geographical diffusion. Our study suggested that different microorganisms exhibited unique evolutionary patterns and may have different assembly modes within phylogenetic groups. Myxomycetes and fungi exhibited a similar assembly process that was mainly influenced by stochastic dispersal limitation and drift. In contrast, bacteria\'s assembly process was primarily influenced by stochastic drift and deterministic homogeneous selection. The community of myxomycetes and fungi is greatly influenced by spatial distribution and random events, while bacteria have a relatively stable population composition in specific regions and may also be subject to environmental constraints. Finally, this study revealed that Humicolopsis cephalosporioides, a fungus that exclusively resided in cold environments, may play a critical role as a keystone species in maintaining molecular ecological networks and was considered a core member of the microbiome.
摘要：
中国寒温带明亮的针叶林地区是一个陆地生态系统，主要以低山落叶松树为主。关于该地区土壤中微生物群落的组装机制和相互作用的信息有限。本研究采用高通量技术从粘菌中获得DNA，细菌,和土壤中的真菌，结合环境因素评估了它们的多样性，将它们与组装过程相关联，并探索了这些微生物之间潜在的相互作用关系。我们的研究结果表明，与粘液菌和真菌相比，环境因素对细菌的α和β多样性的影响更大。微生物群落受到环境选择和地理扩散的影响，尽管环境选择似乎比地理扩散具有更大的影响。我们的研究表明，不同的微生物表现出独特的进化模式，并且在系统发育群体中可能具有不同的组装模式。粘菌和真菌表现出相似的组装过程，主要受随机分散限制和漂移的影响。相比之下,细菌的组装过程主要受随机漂移和确定性同质选择的影响。粘菌和真菌的群落受空间分布和随机事件的影响很大,而细菌在特定地区具有相对稳定的种群组成，并且也可能受到环境限制。最后,这项研究表明，头孢根霉，一种专门生活在寒冷环境中的真菌，作为维持分子生态网络的关键物种，可能发挥关键作用，并被认为是微生物组的核心成员。
