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和人为基础设施构成严重威胁。全球变暖导致冰川迅速退缩，冰层消退后所遗留的无植被沉积物，在降水事件中极易发生移动。因此，冰川前沿的陡峭山坡对侵蚀过程尤为脆弱。植被被公认具有抗侵蚀作用，然而地上地下植物特征、植被覆盖以及群落层面的植物多样性如何相互关联地影响侵蚀尚不明确。植被亦与土壤微生物群落相互联系，共同对土壤功能发挥重要作用，并对边坡稳定性可能产生影响。

我们在奥地利考恩塔尔（Kaunertal）的Gepatschferner冰川（冰川前坡）上，于连续三年的自然原始高山环境中，对30个2 x 3米大小的地块进行了土壤侵蚀运输的测量。对每个出现的植物物种在群落层面上测量了植被覆盖、物种丰富度和相关的地上地下特征。在距离测量点最多1.6公里的地方安装了气象站，每分钟收集一次降水量数据。应用路径模型来梳理植被覆盖、物种（功能）多样性、特征与土壤侵蚀之间的关系。此外，我们利用下一代扩增子测序技术，研究土壤中的细菌和真菌群落与植物群落特征之间的关联。

我们发现，植物群落降低土壤侵蚀运输的最有效属性是密集的整体植被覆盖，这种覆盖得益于物种丰富度，而物种丰富度又得益于植物群落的功能多样性。植被覆盖、物种组成和功能多样性也与土壤微生物群落组成密切相关，这可能促进土壤形成并进一步增强植物对土壤稳定的特性。

包含的数据集：
- 降水量数据
- 植物群落组成
- 每月侵蚀测量
- 植物特征测量

与本研究相关的细菌和真菌序列可通过欧洲核酸序列数据库（ENA）下的ERP133205访问号在fastq文件中获取。