Subglacial Antarctic aquatic environments are important targets for scientific exploration due to the unique ecosystems they support and their sediments containing palaeoenvironmental records. Directly accessing these environments while preventing forward contamination and demonstrating that it has not been introduced is logistically challenging. The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project designed, tested and implemented a microbiologically and chemically clean method of hot-water drilling that was subsequently used to access subglacial aquatic environments. We report microbiological and biogeochemical data collected from the drilling system and underlying water columns during sub-ice explorations beneath the McMurdo and Ross ice shelves and Whillans Ice Stream. Our method reduced microbial concentrations in the drill water to values three orders of magnitude lower than those observed in Whillans Subglacial Lake. Furthermore, the water chemistry and composition of microorganisms in the drill water were distinct from those in the subglacial water cavities. The submicron filtration and ultraviolet irradiation of the water provided drilling conditions that satisfied environmental recommendations made for such activities by national and international committees. Our approach to minimizing forward chemical and microbiological contamination serves as a prototype for future efforts to access subglacial aquatic environments beneath glaciers and ice sheets.

中文翻译：

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环境清洁进入南极冰下水生环境

冰下南极水环境是科学探索的重要目标，因为它们所支持的独特生态系统及其包含古环境记录的沉积物。直接进入这些环境，同时防止前向污染并证明它没有被引入在后勤方面具有挑战性。Whillans 冰流冰下通道研究钻探 (WISSARD) 项目设计、测试和实施了一种微生物和化学清洁的热水钻探方法，该方法随后用于进入冰下水生环境。我们报告了在 McMurdo 和 Ross 冰架和 Whillans 冰流下的冰下勘探期间从钻井系统和底层水柱收集的微生物和生物地球化学数据。我们的方法将钻井水中的微生物浓度降低到比在 Whillans Subglacial Lake 中观察到的低三个数量级的值。此外，钻井水中的水化学和微生物组成与冰下水腔中的不同。水的亚微米过滤和紫外线照射提供了满足国家和国际委员会为此类活动提出的环境建议的钻井条件。我们最大限度地减少前向化学和微生物污染的方法可作为未来努力进入冰川和冰盖下的冰下水生环境的原型。钻井水中的水化学和微生物组成与冰下水腔不同。水的亚微米过滤和紫外线照射提供了满足国家和国际委员会为此类活动提出的环境建议的钻井条件。我们最大限度地减少前向化学和微生物污染的方法可作为未来努力进入冰川和冰盖下的冰下水生环境的原型。钻井水中的水化学和微生物组成与冰下水腔不同。水的亚微米过滤和紫外线照射提供了满足国家和国际委员会为此类活动提出的环境建议的钻井条件。我们最大限度地减少前向化学和微生物污染的方法可作为未来努力进入冰川和冰盖下的冰下水生环境的原型。