Data from: Contrasting microbial biogeographical patterns between anthropogenic subalpine grasslands and natural alpine grasslands

The effect of plant species composition on soil microbial communities was studied at the multiregional level. We compared the soil microbial communities of alpine natural grasslands dominated by Carex curvula and anthropogenic subalpine pastures dominated by Nardus stricta. We conducted paired sampling across the Carpathians and the Alps and used Illumina sequencing to reveal the molecular diversity of soil microbes. We found that bacterial and fungal communities exhibited contrasting regional distributions and that the distribution in each grassland is well discriminated. Beta diversity of microbial communities was much higher in C. curvula grasslands due to a marked regional effect. The composition of grassland-type core microbiomes suggest that C. curvula, and N. stricta to a lesser extent, tend to select a cohort of microbes related to antibiosis/exclusion, pathogenesis and endophytism. We discuss these findings in light of the postglacial history of the studied grasslands, the habitat connectivity and the disturbance regimes. Human-induced disturbance in the subalpine belt of European mountains has led to homogeneous soil microbial communities at large biogeographical scales. Our results confirm the overarching role of the dominant grassland plant species in the distribution of microbial communities and highlight the relevance of biogeographical history.

本研究在多区域尺度下探究了植物物种组成对土壤微生物群落的影响。我们对比了以弯叶苔草（Carex curvula）为优势种的高山天然草原，以及以硬绒毛草（Nardus stricta）为优势种的人为干扰亚高山牧场。我们在喀尔巴阡山脉与阿尔卑斯山脉开展配对采样，并利用Illumina测序（Illumina sequencing）技术解析土壤微生物的分子多样性。研究发现，细菌与真菌群落呈现出截然不同的区域分布模式，且两类草原各自的微生物群落分布均可被清晰区分。由于显著的区域效应，弯叶苔草草原的微生物群落β多样性（beta diversity）显著更高。草原型核心微生物组（core microbiome）的组成特征表明，弯叶苔草（C. curvula）以及硬绒毛草（Nardus stricta，仅在较小程度上）倾向于筛选出与抗生作用/排他性、致病作用以及内生定殖相关的微生物类群。我们结合研究草原的冰后历史、生境连通性以及干扰制度，对上述研究结果展开讨论。欧洲山地亚高山带的人为干扰，已导致大生物地理尺度下的土壤微生物群落趋于均质化。本研究结果证实了草原优势植物物种在微生物群落分布中的核心调控作用，并凸显了生物地理历史的研究价值。