Abstract：
Glaciers, which constitute the world\'s largest global freshwater reservoir, are also natural microbial repositories. The frequent pandemic in recent years underscored the potential biosafety risks associated with the release of microorganisms from the accelerated melting of glaciers due to global warming. However, the characteristics of pathogenic microorganisms in glaciers are not well understood. The glacier surface is the primary area where glacier melting occurs that is often the main subject of research on the dynamics of pathogenic microbial communities in efforts to assess glacier biosafety risks and devise preventive measures. In this study, high-throughput sequencing and quantitative polymerase chain reaction methods were employed in analyses of the composition and quantities of potential pathogenic bacteria on the surfaces of glaciers in the southeastern Tibetan Plateau. The study identified 441 potential pathogenic species ranging from 215 to 4.39 × 1011 copies/g, with notable seasonal and environmental variations being found in the composition and quantity of potential pathogens. The highest level of diversity was observed in April and snow, while the highest quantities were observed in October and cryoconite. Host analysis revealed that >70 % of the species were pathogens affecting animals, with the highest proportion of zoonotic pathogens being observed in April. Analysis of aerosols and glacial meltwater dispersion suggested that these microbes originated from West Asia, primarily affecting the central and southern regions of China. Null model analysis indicated that the assembly of potential pathogenic microbial communities on glacier surfaces was largely governed by deterministic processes. In conclusion, potential pathogenic bacteria on glacier surfaces mainly originated from the snow and exhibited significant temporal and spatial variation patterns. These findings can be used to enhance researchers\' ability to predict potential biosafety risks associated with pathogenic bacteria in glaciers and to prevent their negative impact on populations and ecological systems.
摘要：
冰川,构成了世界上最大的全球淡水水库，也是天然微生物储存库。近年来频繁的大流行突显了与全球变暖导致的冰川加速融化释放微生物相关的潜在生物安全风险。然而,冰川中病原微生物的特征还没有得到很好的理解。冰川表面是冰川融化的主要区域，通常是病原微生物群落动态研究的主要主题，以评估冰川生物安全风险并制定预防措施。在这项研究中,采用高通量测序和定量聚合酶链反应方法分析了青藏高原东南部冰川表面潜在致病菌的组成和数量。该研究确定了441种潜在的致病物种，范围为215至4.39×1011拷贝/g，在潜在病原体的组成和数量中发现了显着的季节性和环境变化。多样性的最高水平在四月和雪中观察到，而最高的数量是在10月份和冰冻岩。宿主分析显示，>70％的物种是影响动物的病原体，4月份观察到的人畜共患病原体比例最高。对气溶胶和冰川融水扩散的分析表明，这些微生物起源于西亚，主要影响中国中部和南部地区。零模型分析表明，冰川表面上潜在病原微生物群落的组装在很大程度上受到确定性过程的控制。总之,冰川表面潜在的病原菌主要来源于雪，并表现出显著的时空变异模式。这些发现可用于提高研究人员预测与冰川病原菌相关的潜在生物安全风险的能力，并防止其对种群和生态系统的负面影响。
