School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, 2052, Australia.
Sci Rep. 2017 Mar 14;7:44480. doi: 10.1038/srep44480.
Heard Island in the Southern Ocean is a biological hotspot that is suffering the effects of climate change. Significant glacier retreat has generated proglacial lagoons, some of which are open to the ocean. We used pyrotag sequencing of SSU rRNA genes and environmental data to characterize microorganisms from two pools adjacent to animal breeding areas, two glacial lagoons and Atlas Cove (marine site). The more abundant taxa included Actinobacteria, Bacteroidetes and Proteobacteria, ciliates and picoflagellates (e.g. Micromonas), and relatively few Archaea. Seal Pool, which is rich in organic matter, was characterized by a heterotrophic degradative community, while the less eutrophic Atlas Pool had more eucaryotic primary producers. Brown Lagoon, with the lowest nutrient levels, had Eucarya and Bacteria predicted to be oligotrophs, possess small cell sizes, and have the ability to metabolize organic matter. The marine influence on Winston Lagoon was evident by its salinity and the abundance of marine-like Gammaproteobacteria, while also lacking typical marine eucaryotes indicating the system was still functioning as a distinct niche. This is the first microbiology study of Heard Island and revealed that communities are distinct at each location and heavily influenced by local environmental factors.
南大洋的赫德岛是一个生物热点地区，正遭受气候变化的影响。显著的冰川后退产生了前冰川泻湖，其中一些与海洋相通。我们使用 SSU rRNA 基因的焦磷酸测序和环境数据来描述靠近动物繁殖区的两个水池、两个冰川泻湖和阿特拉斯湾（海洋地点）的微生物。更丰富的类群包括放线菌、拟杆菌门和变形菌门、纤毛虫和微微鞭毛虫（例如 Micromonas），以及相对较少的古菌。富含有机物的海豹池的特征是异养降解群落，而营养水平较低的无磷阿特拉斯池则具有更多的真核初级生产者。布朗泻湖的营养水平最低，预测其真核生物和细菌为贫营养生物，具有小细胞尺寸，并具有代谢有机物的能力。温斯顿泻湖的海洋影响体现在其盐度和类似海洋的γ变形菌门的丰度上，同时也缺乏典型的海洋真核生物，表明该系统仍在作为一个独特的小生境运作。这是对赫德岛的第一次微生物学研究，结果表明，每个地点的群落都有明显的差异，并且受到当地环境因素的强烈影响。
