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

合作研究：冰下南极湖泊科学访问（SALSA）：水文活跃冰下环境中碳循环的综合研究

• 批准号: 1543347
• 负责人: Brad Rosenheim
• 金额: $ 32.01万
• 依托单位: University of South Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1543347&HistoricalAwards=false
• 关键词: Collaborative; Research; Subglacial; Antarctic; Lakes

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.

南极冰下环境仍然是地球上开发最少的地区之一。该项目将研究位于西南极冰盖下1200米的冰下梅瑟湖的物理和生物特征。这项研究将解决与冰盖、冰下水文系统和深冷冰下生物圈的稳定性有关的关键问题。教育和宣传部分旨在通过短片、博客和网站向科学界和公众广泛传播成果。冰下梅瑟湖是西南极惠兰冰原南部盆地较大的水文活跃湖泊之一。它大约25%的水来自南极洲东部，其余的来自南极洲西部，受到上游湖(冰下康威湖)排水/填充循环的影响，位于罗斯冰架目前的接地线上游约100公里处。该网站将提供有关惠兰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在三年的时间里结合表面地球物理调查对湖底冰、水和沉积物进行直接采样，以确定惠兰冰原上湖泊之间的水文连通性及其流向大海的路径。地球物理调查将提供有关冰川下水文学的信息，帮助选择热水钻探的地点，并为解释调查结果提供空间背景。热水钻孔将用于收集基础冰样，为直接测量水柱和沉积物中的冰下物理、化学和生物条件提供通道，并使用配备传感器、相机和采样设备的遥控运载器探索冰下水洞。从这项研究中收集的数据将解决最重要的假设：“与Mercer和Whillans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留海洋有机质的矿化和循环以及冰、岩石、水和沉积物之间的相互作用的调节”。该项目将由一个合作的科学家团队承担，他们拥有微生物学、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方面的专业知识。