Significance of Ice-loss to Landscapes in the Arctic: SILA (Inuit concept of the physical world and weather)

在过去的300万年里，大约15%的地球陆地表面都经历了冰盖的进退。这种冰川循环产生的细颗粒沉积物很容易被化学反应改变。随着冰川退缩，景观暴露，生态系统发展，沉积物发生反应，溪流成分发生变化。在格陵兰岛西南部，排出冰川融水的河流和从冰川融水中分离出来的非冰川河流相对于其排泄区域排出的水量相似，但由于化学成分不同，它们向大气输送的温室气体和向沿海生态系统输送的营养物质的量不同。这些差异可能会影响气候、生态系统和人类，这凸显了向公众有效传播冰川环境变化的必要性。发展有效的沟通技巧是这项跨学科研究的一个组成部分，该研究旨在评估生物、地球化学和水文过程如何在冰川退缩时控制水流成分。这一认识将加强对过去冰川退缩的影响以及对未来北极变暖的反应的评估。项目成果将通过环境公民分享，这是一个将提高研究人员科学交流和领导技能的组成部分。沉积物组成、暴露年龄、植物和微生物定植、水的可利用性以及河流与景观的联系被假设为在冰周流域中系统地变化，从而控制风化程度、河流地球化学以及溶质和气体通量。这一假设将由一个由美国和格陵兰研究人员组成的跨学科小组在两个融化季节从格陵兰冰盖延伸到海岸的流域进行测试，他们将a)测量非冰川河流流量、溶质和气体浓度和通量、微生物群落结构、植物群落分布、碳和营养循环，以及河流和河床沉积物中的放射性同位素；B)维护自动天气观测、粉尘收集和溪流化学记录仪；c)进行流加药实验。这些数据将揭示风化程度、生态系统特征、生物地球化学过程和河流化学之间的反馈及其对冰缘流域溶质和气体通量的控制作用。在与格陵兰同事的合作下，研究结果将为环境公民计划提供种子，通过教师教育计划制定和实施适合格陵兰高中水平的环境科学课程，并为格陵兰的旅游业、格陵兰的中学和北极技术中心制作教育材料。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Ice sheets have advanced and retreated across approximately 15% of Earth’s land surface over the past three million years. This glacial cycling produces fine-grained sediments that are easily altered by chemical reactions. As glacial retreat exposes landscapes, ecosystems develop, sediments react, and stream water compositions change. In southwestern Greenland, streams draining glacial meltwater and non-glacial streams separated from glacial meltwater discharge similar amounts of water relative to their drainage areas, but because of distinct chemical compositions, they deliver differing amounts of greenhouse gases to the atmosphere and nutrients to coastal ecosystems. These differences may affect climate, ecosystems, and people, highlighting the need for effective communication of glacial environmental changes to the public. Developing effective communication skills is an integral part of this interdisciplinary study to evaluate how biological, geochemical, and hydrologic processes control stream water composition as glaciers retreat. This insight will enhance evaluations of the effects from past glacial retreat and responses to future Arctic warming. Project results will be shared through environmental civics, a component that will improve researchers’ science communication and leadership skills. Sediment compositions, exposure age, plant and microbe colonization, water availability, and stream-landscape connections are hypothesized to vary systematically across periglacial watersheds and thus control weathering extent, stream geochemistry, and solute and gas fluxes. This hypothesis will be tested in watersheds stretching from the Greenland Ice Sheet to the coast over two melt seasons by an interdisciplinary group of U.S. and Greenlandic researchers who will a) measure non-glacial stream discharge, solute and gas concentrations and fluxes, microbial community structures, plant community distributions, carbon and nutrient cycling, and radiogenic isotopes in stream and bedload sediment; b) maintain automated weather observations, dust collection, and stream chemistry loggers; and c) perform stream dosing experiments. These data will reveal feedbacks between weathering extent, ecosystem characteristics, biogeochemical processes, and stream chemistry and their controls on solute and gas fluxes from periglacial watersheds. In collaboration with Greenlandic colleagues, the results will seed environmental civics plans to develop and implement environmental science curricula at levels appropriate to Greenlandic high schools through a teacher-education program and to create educational materials for tourism in Greenland, Greenlandic secondary schools, and the Arctic Technology Center.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.