Table_4_Variation in Soil Microbial Communities Along an Elevational Gradient in Alpine Meadows of the Qilian Mountains, China.xlsx

Bacterial, archaeal, and eukaryota diversity in mountainous areas varies along elevational gradients, but details remain unclear. Here, we use a next-generation sequencing method based on 16S/18S rRNA to reveal the soil microbial diversity and community compositions of alpine meadow ecosystems along an elevation span of nearly 2,000 m (1,936–3,896 m) in China’s Qilian Mountains. Both bacterial and eukaryota diversity increased linearly with increasing elevation, whereas archaeal diversity increased, but not significantly. The diversity patterns of several phyla in the bacterial, archaeal, and eukaryota communities were consistent with the overall elevational trend, but some phyla did not follow this pattern. The soil microbial community compositions were shaped by the coupled effects of regional climate and local soil properties. Intradomain links were more important than interdomain links in the microbial network of the alpine meadows, and these links were mostly positive. The bacteria formed more connections than either archaea or eukaryota, but archaea may be more important than bacteria in building the soil microbial co-occurrence network in this region. Our results provide new visions on the formation and maintenance of soil microbial diversity along an elevational gradient and have implications for microbial responses to climate change in alpine ecosystems.

山地环境中细菌、古菌与真核生物的多样性随海拔梯度发生变化，但其详细规律仍不明确。本研究采用基于16S/18S核糖体RNA（16S/18S rRNA）的下一代测序技术，揭示了中国祁连山近2000米海拔跨度（1936–3896米）内高寒草甸生态系统的土壤微生物多样性与群落组成。研究发现，细菌与真核生物多样性随海拔升高呈线性增加趋势，而古菌多样性虽呈上升态势，但未达到显著水平。细菌、古菌和真核生物群落中多个菌门的多样性分布模式与整体海拔梯度趋势相符，但亦有部分菌门并未遵循该规律。土壤微生物群落组成受区域气候与局地土壤理化性质的共同调控。在高寒草甸微生物共现网络中，域内关联比域间关联更为关键，且多数关联呈正相关。细菌的连接数量多于古菌与真核生物，但在本区域土壤微生物共现网络的构建中，古菌或许发挥了比细菌更为重要的作用。本研究为海拔梯度下土壤微生物多样性的形成与维持机制提供了新的认知视角，并为高寒生态系统中微生物对气候变化的响应研究提供了理论参考。