Bacterial Communities in Cryoconite Holes of the Adjacent Glaciers on the Tibetan Plateau

Abstract

Cryoconite holes are biological hotspots on the glacier surface. Cryoconite bacterial communities are strongly spatially heterogeneous at the regional scale which is closely associated with environmental variables and geographic distance. However, knowledge about the distribution patterns of cryoconite bacterial communities at a small scale and the underlying drivers is still limited. Here, we investigated bacterial communities in cryoconite holes of two adjacent glaciers of Tangula mountain range, DKMD (Dongkemadi) and LXZLB (Longxiazailongba) glacier, on the Tibetan Plateau using amplicon sequencing of the 16S rRNA gene. Cryoconite bacteria on the two glaciers have similar alpha diversity, but significantly different community compositions. Geospatial factors were the most important drivers (24.0% of the community variation) for predicting the cryoconite bacterial beta diversity in both glaciers. Latitude was the primary driver of the beta diversity of bacterial communities in the DKMD glacier, while the depth of the cryoconite holes played a dominant role in the LXZLB glacier. Collectively, these results demonstrated cryoconite bacterial communities exhibited spatial heterogeneity even at the small local scale and highlighted the importance of morphological properties of cryoconite holes instructing the distribution of cryoconite bacterial communities.