Cross-range comparison of supraglacial microbial communities between Gongga and Gangrigabu mountains, Southeast Tibetan Plateau

We hypothesized that supraglacial microbial communities would exhibit distinct biogeographical patterns across mountain ranges due to geographic isolation and environmental heterogeneity, with bacterial communities being more strongly influenced by local environmental factors than fungal communities.

To test this hypothesis, supraglacial debris samples were collected from multiple glaciers in the Gongga and Gangrigabu mountain ranges, located in the southeastern Tibetan Plateau. Microbial community composition was characterized using high-throughput sequencing of the bacterial 16S rRNA gene (V3–V4 region) and fungal ITS region on the Illumina MiSeq platform. Raw sequence data were processed using standard bioinformatics pipelines to obtain quality-filtered reads, amplicon sequence variants (ASVs), and taxonomic assignments. In parallel, physicochemical parameters, including pH and nutrient concentrations (e.g., nitrate nitrogen), were measured for each sample to assess environmental influences on microbial community structure.

我们提出如下假说：由于地理隔离与环境异质性，冰川表面微生物群落在不同山脉间会呈现出显著的生物地理分布格局；且细菌群落相较于真菌群落，受局地环境因子的影响更为强烈。
为验证该假说，研究团队于青藏高原东南部的贡嘎山及岗日嘎布山脉的多条冰川中采集了冰川表面冰碛物样本。采用Illumina MiSeq测序平台，对细菌16S rRNA基因（V3–V4区）与真菌ITS区进行高通量测序，以此表征微生物群落组成。原始测序数据通过标准生物信息学流程进行处理，最终获得质控过滤后的读段、扩增子序列变体（amplicon sequence variants, ASVs）以及物种分类学注释结果。与此同时，我们还为每份样本测定了包括pH值与营养盐浓度（如硝态氮）在内的理化参数，以评估环境因子对微生物群落结构的影响。