Collaborative Research: Greenland Meltwater Geomicrobiology

格陵兰冰原（GrIS）是北极最大的淡水水库。GrIS正在加速融化，向北冰洋输送大量淡水。GrIS以下微生物群落的性质和组成尚不清楚，但最近的研究表明，在其他冰下环境和GrIS冰本身中存在可行的微生物群落，表明它们对化学风化过程的潜在重要性。这个项目将成为GrIS的特色。冰下微生物群落研究微生物对西格陵兰GrIS边缘岩石圈风化和养分通量的影响。该假说认为，冰川热状态和基岩岩性是冰下细菌群落的主要决定因素，而细菌群落反过来又调节养分释放和风化速率。Thule和kangerluswaaq地区的研究地点涵盖了西格陵兰岛的两种主要岩性。这项研究结合了最先进的微生物学、生物地球化学技术，以及河流和气候参数的数据记录，以检查冰川融水。预计GrIS的融化将对全球生物地球化学循环、海洋生态和大气CO2产生重大影响。预计GrIS冰下微生物在动员岩石圈元素方面起着重要作用。关于GrIS微生物（细菌、古生菌和真核菌）多样性的数据将提供GrIS下水生生境微生物丰富度和多样性的初步评估。主要目的是研究生物多样性和微生物对地球化学过程和养分释放的贡献，这项研究还将为迄今为止尚未研究过的冰下环境中生命的低温适应提供见解。与WISSARD（威廉姆斯冰流冰下通道研究钻探）项目的协同关系将为格陵兰岛和南极西部冰盖下生物多样性的两极比较提供机会。提供GrIS释放的融水（特别是碳、铁和微量营养素）和沉积物的化学成分和通量的数据，将为评估全球生物地球化学模型中的潜在反馈提供一个框架。两个融冰季节的详细测量将为GrIS？冰下微生物环境。

The Greenland Ice Sheet (GrIS) is the largest freshwater reservoir in the Arctic. Melting of the GrIS is increasing, delivering large amounts of freshwater to the Arctic Ocean. The nature and composition of microbial communities below the GrIS are not known, but recent studies have documented the presence of viable microbial communities in other subglacial environments and within the GrIS ice itself, indicating their potential importance for chemical weathering processes. This project will characterize GrIS? subglacial microbial communities to investigate the effect of microbes on lithospheric weathering and nutrient fluxes from the GrIS margin in West Greenland. The hypothesis is that the glacial thermal regime and bedrock lithology are the primary determinants of the subglacial bacterial communities, which in turn mediate nutrient release and weathering rates. Study sites in the Thule and Kangerlusuaq areas cover two major lithologies of West Greenland. The study combines state-of-the art microbiological, biogeochemical techniques, and datalogging of stream and climate parameters, to examine glacial meltwater. It is anticipated that the melting of the GrIS will have large effects on global biogeochemical cycles, ocean ecology, and atmospheric CO2. GrIS subglacial microbes are anticipated to play an important role in mobilizing elements from the lithosphere. Data generated on the diversity of GrIS microbes (Bacteria, Archaea and Eukarya) will provide an initial assessment of microbial richness and diversity in aquatic habitats beneath the GrIS. The primary objective is to examine the biodiversity and microbial contribution to geochemical processes and nutrient release, and this study will also provide insight into low temperature adaptation of life in and to a hitherto unexamined subglacial environment. A synergistic relationship with the WISSARD (Whillams Ice Stream Subglacial Access Research Drilling) project will provide the opportunity for a bipolar comparison of biodiversity beneath the Greenland and West Antarctic ice sheets. Providing data of chemical composition and fluxes of meltwater (particularly carbon, iron and trace nutrients) and sediments released by the GrIS will provide a framework to assess potential feedbacks in global biogeochemical models. Detailed measurements over two melting seasons will provide fundamental data towards a conceptual model of GrIS? subglacial microbial environments.