Supporting dataset: Alpine slopes are protected against erosion by functionally diverse and dense plant communities associated with specific microbial communities

Soil erosion is a severe threat for ecosystems and anthropogenic infrastructure. Glaciers are retreating rapidly due to global warming and the receding ice leaves unvegetated depositions of sediment, which are prone to mobilisation during precipitation events. Steep slopes in glacier forelands are therefore particularly vulnerable to erosion processes. Vegetation is known to serve as erosion protection, but how above-and belowground plant traits, vegetation cover and plant diversity on community level are interrelatedly affecting erosion is unclear. Vegetation is also linked to soil microbial communities, which together play important roles for soil functions with possible implications for slope stability. We measured sediment transport on 30 plots of 2 x 3 m size on proglacial slopes of the Gepatschferner glacier (Kaunertal, Austria) over three consecutive years in a natural pristine high alpine environment. Vegetation cover, species abundances and relevant above- and belowground traits were measured for each occurring plant species on community level. A weather station was installed at a maximum distance of 1.6 km from the measurement sites, collecting precipitation data once per minute. A path model was applied to detangle the relationships between plant cover, species (functional) diversity, traits, and soil erosion. Further, we used next generation amplicon sequencing to investigate how bacterial and fungal communities in the soil are related to the plant community characteristics. We found that the most effective property of a plant community for decreasing sediment transport was a dense overall plant cover, which was facilitated by plant species richness, which was in turn facilitated by functional diversity of plant communities. Plant cover, species composition and functional diversity were also closely linked to the composition of soil microorganisms, which may facilitate soil formation and further enhance the plants’ soil stabilising properties. Included datasets: - Precipitation data - Plant community composition - Monthly erosion measurements - Plant trait measurements Bacterial and fungal sequences associated with this study can be accessed in fastq files deposited in the European Nucleotide Archive (ENA) under the accession number ERP133205.土壤侵蚀对生态系统及人工基础设施均构成严重威胁。全球变暖导致冰川快速退缩，退缩后裸露的沉积物堆积体缺乏植被覆盖，极易在降水事件中被侵蚀搬运。因此，冰川前缘的陡坡区域尤其易受侵蚀作用影响。已知植被可起到侵蚀防护作用，但目前尚不清楚群落层面的植物地上、地下性状、植被覆盖度以及植物多样性是如何协同影响侵蚀过程的。植被同时与土壤微生物群落存在关联，二者共同对土壤功能发挥重要作用，进而可能影响边坡稳定性。 本研究在奥地利考纳塔尔（Kaunertal）的格帕奇费纳冰川（Gepatschferner）前缘的天然原生高海拔高山环境中，于30块面积为2×3米的样地开展了连续三年的沉积物搬运量测定。针对群落内所有出现的植物物种，测定了其植被覆盖度、物种多度以及相关的地上、地下功能性状。在距样地最大直线距离1.6公里处布设了一座气象站，以每分钟一次的频率采集降水数据。本研究采用路径模型厘清了植被覆盖度、物种（功能）多样性、植物性状与土壤侵蚀之间的关联关系。此外，本研究借助下一代扩增子测序技术，探究了土壤细菌与真菌群落如何与植物群落特征产生关联。 研究结果表明，植物群落降低沉积物搬运量的最有效特征为整体植被覆盖度较高，而这一覆盖度的提升得益于植物物种丰富度，物种丰富度则进一步受植物群落功能多样性的促进。植被覆盖度、物种组成以及功能多样性同时与土壤微生物群落组成密切相关，这一关联可促进土壤形成，并进一步强化植物的土壤固持效应。 本研究包含以下数据集： - 降水数据 - 植物群落组成数据 - 月度侵蚀测定数据 - 植物性状测定数据 本研究相关的细菌与真菌序列可通过欧洲核苷酸档案库（European Nucleotide Archive, ENA）中编号为ERP133205的fastq文件获取。