Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments

南极冰下环境仍然是地球上探索最少的地区之一。 该项目将研究冰下默瑟湖的物理和生物特征，默瑟湖位于西南极冰盖下方 1200 m 处。 这项研究将解决与冰盖稳定性、冰下水文系统和深冷冰下生物圈相关的关键问题。 教育和推广部分旨在通过短片、博客和网站向科学界和公众广泛传播研究成果。默瑟冰下湖是南极洲西部威兰斯冰原南部盆地较大的水文活跃湖泊之一。 它约 25% 的水来自南极洲东部，其余的水来自南极洲西部，受到上游湖泊（康威冰下湖）排水/填充循环的影响，位于罗斯冰架现有接地线上游约 100 公里处。 该站点将提供有关威兰斯冰流和默瑟冰流的历史以及接地线迁移的信息。 这项综合研究将包括对湖泊的基底冰、水和沉积物进行直接采样，并结合三年的地表地球物理调查，以确定威兰斯冰原湖泊之间的水文连通性及其通往海洋的流动路径。地球物理调查将提供冰下水文信息，帮助热水钻探地点选择，并为解释结果提供空间背景。热水钻孔将用于收集基底冰样本，为直接测量冰下水柱和沉积物中的物理、化学和生物状况提供通道，并使用配备传感器、摄像机和采样设备的远程操作车辆探索冰下水洞。这项研究收集的数据将解决总体假设“与默瑟和惠兰斯冰流相关的水文活跃的冰下环境中的当代生物多样性和碳循环受到残余海洋有机物的矿化和循环以及冰、岩石、水和沉积物之间相互作用的调节”。该项目将由拥有微生物学、生物地球化学、水文学、地球物理学、冰川学、海洋地质学、古海洋学和科学传播专业知识的科学家合作团队承担。

The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.Subglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis "Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.