Raw sequencing data for studying the colonization of soil communities after glacier retreat

Glaciers show a pattern of retreat at the global scale. Deglaciated areas are exposed and colonized by multiple organisms, but lack of global studies hampers a complete understanding of the future of these ecosystems. Until now, the complete reconstruction of soil communities was hampered by the complex identification of organisms, thus analyses at broad geographical and taxonomic scale have been so far impossible. The dataset used for this study represents the assemblages of Bacteria, Mycota, Eukaryota, Collembola (springtails), Oligochaeta (Earth worms), Insecta, Arthropoda and Vascular Plants obtained using environmental DNA (eDNA) metabarcoding. eDNA was extracted from soil samples collected from multiple glacier forelands representative of some of the main mountain chains of Europe, Asia, the Americas and Oceania. We investigated chronosequences of glacier retreat (i.e., the chronological sequence of specific geomorphological features along deglaciated areas for which the date of glacier retreat is known) ranging from recent years to the Little Ice Age (~1850). We used this newly assembled global DNA metabarcoding dataset to obtain a complete reconstruction of community changes in novel ecosystems after glacier retreat. Information on assemblages can be then combined with analyses of soil, landscape and climate to identify the drivers of community changes.

全球范围内冰川均呈现消退态势。冰川消退后裸露的区域会被多种生物定植，但缺乏全球尺度的研究阻碍了我们对这些生态系统未来的全面认知。此前，由于生物类群鉴定流程复杂，土壤群落的完整重构工作始终难以推进，因此无法开展大地理范围与宽分类学尺度的相关分析。
本研究使用的数据集涵盖了通过环境DNA（eDNA）宏条形码技术获取的细菌域（Bacteria）、真菌界（Mycota）、真核生物域（Eukaryota）、弹尾目（Collembola，俗称跳虫）、寡毛纲（Oligochaeta，俗称蚯蚓）、昆虫纲（Insecta）、节肢动物门（Arthropoda）以及维管植物（Vascular Plants）的群落组成。研究人员从覆盖欧洲、亚洲、美洲与大洋洲主要山系的多处冰川前缘（glacier forelands）采集土壤样本，并从中提取eDNA。
本研究聚焦的冰川消退时间序列（chronosequences，即冰退区域内已知冰川消退时间的特定地貌特征的时间序列）涵盖了从近年到小冰期（约1850年）的范围。
本研究借助这一全新构建的全球eDNA宏条形码数据集，实现了冰川消退后新生生态系统群落变化的完整重构。后续可将群落组成信息与土壤、景观及气候相关分析相结合，以明确群落变化的驱动因子。