Department of Earth and Environmental Sciences (DISAT), Università degli Studi di Milano-Bicocca, Milan, Italy.
WSL Swiss Federal Research Institute, Birmensdorf, Switzerland.
Sci Rep. 2023 Feb 14;13(1):2633. doi: 10.1038/s41598-022-24373-5.
Cryoconite holes, ponds full of melting water with sediment on the bottom, are hotspots of biodiversity on glacier surfaces and host dynamic micro-ecosystems. They have been extensively investigated in different areas of the world (e.g., the Arctic, Antarctic, Alps, and Himalaya), but so far no study has described the bacterial communities of the glaciers in the Andes, the world's longest mountain range. In this study, we describe the bacterial communities of three small (< 2 km) high-elevation (< 4200 m a.s.l.) glaciers of the Central Andes (Iver, East Iver and Morado glaciers) and two large (> 85 km) glaciers of the Patagonian Andes (Exploradores and Perito Moreno glaciers) whose ablation tongues reach low altitude (< 300 m a.s.l.). Results show that the bacterial communities were generally similar to those observed in the cryoconite holes of other continents, but with few cyanobacteria (0.5% of sequences). The most abundant orders were Betaproteobacteriales, Cytophagales, Chitinophagales, Acetobacterales, Frankiales, Armatimonadales, Sphingobacteriales, Rhizobiales, Bacteroidales, Sphingomonadales, and Micrococcales. The bacterial communities differed between glaciers and both water pH and O concentration appeared to influence the bacterial community composition. This work thus provides the first description of the bacterial communities in cryoconite holes of South American glaciers.
冰核洞是充满融水和底部沉积物的池塘，是冰川表面生物多样性的热点，也是动态微生物生态系统的所在地。它们在世界上的不同地区（如北极、南极、阿尔卑斯山和喜马拉雅山）已经得到了广泛的研究，但迄今为止，还没有研究描述过安第斯山脉冰川的细菌群落，安第斯山脉是世界上最长的山脉。在这项研究中，我们描述了安第斯山脉中部的三个小（<2 公里）高海拔（<4200 米海拔）冰川（Iver、East Iver 和 Morado 冰川）和两个大型（>85 公里）安第斯山脉冰川（Exploradores 和 Perito Moreno 冰川）的细菌群落，其消融舌到达低海拔（<300 米海拔）。结果表明，细菌群落通常与在其他大陆的冰核洞观察到的群落相似，但蓝细菌较少（占序列的 0.5%）。最丰富的目是贝塔变形菌目、噬纤维菌目、噬几丁质菌目、醋杆菌目、弗兰克氏菌目、Armatimonadales、鞘脂单胞菌目、根瘤菌目、拟杆菌目、鞘氨醇单胞菌目和微球菌目。冰川之间的细菌群落存在差异，水的 pH 值和 O 浓度似乎都影响了细菌群落的组成。因此，这项工作首次描述了南美的冰核洞中的细菌群落。
