Duan Yulong, Zhang Junbiao, Petropoulos Evangelos, Zhao Jianhua, Jia Rongliang, Wu Fasi, Chen Yun, Wang Lilong, Wang Xuyang, Li Yulin, Li Yuqiang
Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
Naiman Desertification Research Station, Northwest Institute of eco-Environment and Resources, Chinese Academy of Sciences, Tongliao, China.
Glob Chang Biol. 2025 Apr;31(4):e70174. doi: 10.1111/gcb.70174.
Soil microbiome is essential for terrestrial ecosystem preservation. β-diversity information on the former, although dynamic due to its sensitivity to environmental conditions driven by climate change, is limited. Our knowledge becomes poorer for microbiomes subjected to environmental gradients, especially for those across multiple ecosystems-information important for biological conservation management. In this study, using next generation sequencing and machine learning at samples from 207 locations among 4300 km of transects that spanned among six typical terrestrial ecosystems of China, we established the divergent distance-decay relationships between bacterial and eukaryotic communities in response to soil pH (pH as proxy of climate and edaphic conditions). The findings, pH-decrease results in lower β-diversity (convergent tendency) among the bacterial communities opposite to the eukaryotic ones (low pH-high β-diversity (divergent tendency)). Meanwhile, competition between bacteria and eukaryotes intensifies at lower pH while the predominant genera and communities are re-structured. Under these circumstances, potential soil acidification due to climate change or other factors could alter soil bacteria and eukaryotes into decoupling directions influencing ecosystems' stability. Thus, soil pH is a pivotal environmental variable that not only describes, but also controls, soil microbiome dynamics at a large scale under ongoing global changes; hence, a cornerstone variable for the biodiversity conservation of China's nature protected areas and not only.
土壤微生物群对陆地生态系统的保护至关重要。尽管前者的β多样性信息由于对气候变化驱动的环境条件敏感而具有动态性，但仍然有限。对于受环境梯度影响的微生物群，尤其是跨越多个生态系统的微生物群，我们的了解更少，而这些信息对于生物保护管理很重要。在本研究中，我们利用下一代测序技术和机器学习方法，对中国六个典型陆地生态系统中4300公里样带的207个地点的样本进行分析，建立了细菌和真核生物群落之间不同的距离-衰减关系，以响应土壤pH值（pH值作为气候和土壤条件的代理）。研究结果表明，pH值降低会导致细菌群落的β多样性降低（趋同趋势），这与真核生物群落相反（低pH值-高β多样性（趋异趋势））。同时，细菌和真核生物之间的竞争在较低pH值下加剧，而优势属和群落则会重新构建。在这种情况下，气候变化或其他因素导致的潜在土壤酸化可能会使土壤细菌和真核生物朝着影响生态系统稳定性的解耦方向发展。因此，土壤pH值是一个关键的环境变量，它不仅描述，而且控制着全球变化背景下大规模土壤微生物群的动态；因此，它不仅是中国自然保护区生物多样性保护的基石变量。
