Collaborative Research: Carbon, Water, and Energy Balance of the Arctic Landscape at Flagship Observatories in Alaska and Siberia

北极陆地生态系统与大气交换温室气体（二氧化碳和甲烷）、水蒸气和能量。这些量的吸收和释放之间的平衡影响北极地区和全球气候系统。碳、水和能源的陆地循环紧密相连，因此需要在同一时间、同一地点进行研究。该项目继续对阿拉斯加北极地区陆地和淡水系统的碳、水和能量平衡进行长期测量，扩展了2007年开始的测量。在我们的一个研究地点，随着冬季空气和土壤温度的升高，冬季的碳损失最近急剧增加。这项研究将确定这些损失是否会继续，并试图了解潜在的原因。该项目的更广泛影响包括对教学和学习的贡献，包括代表性不足的群体，对本科生暑期研究的支持，参与海洋生物实验室洛根科学新闻项目和北极LTER校园项目，以及向阿拉斯加费尔班克斯的K-12学校和阿拉斯加土著社区推广。该项目将支持UAF两位女性首席研究员的职业发展。拟议中的研究将扩展对阿拉斯加Imnavait Creek附近三个冻土带生态系统的碳、水和能量平衡的连续测量。自2007年以来，通过涡旋相关方差在这些站点收集了生态系统/大气通量测量数据。将继续长期监测Imnavait溪的水文和河流化学及其集水区的解冻深度。帮助解释这些数据的其他测量将包括地下水位深度、植物群落组成和通过反射率获得的植被绿化率，反射率与叶面积和生物量有关。在Imnavait也可以获得对河流化学和排放的长期测量，从而对碳预算进行全面评估。所有数据将在北极长期生态研究（LTER）网站、国际北极研究中心数据档案和北极高级合作数据和信息服务（ACADIS）中公开提供和存档。

Arctic terrestrial ecosystems exchange greenhouse gases (carbon dioxide and methane), water vapor, and energy with the atmosphere. The balance between uptake and release of these quantities influences both the Arctic region and the global climate system. The terrestrial cycling of carbon, water, and energy are strongly linked, and therefore need to be studied at the same time and in the same place. This project continues long-term measurements of carbon, water, and energy balance in terrestrial and freshwater systems in the Alaskan Arctic, extending measurements that began in 2007. Carbon loss over the winter has recently increased dramatically at one of our study sites, as winter air and soil temperatures have warmed. This study will determine whether these losses continue and seek to understand the underlying causes. Broader impacts of this project include contributions to teaching and learning, including underrepresented groups, support of undergraduate summer research, participation in the Marine Biology Laboratory Logan Science Journalism program and the Arctic LTER Schoolyard program, and outreach to K-12 schools in Fairbanks, Alaska, and to Native Alaskan communities. This project will support career development of two female Principal Investigators at UAF.The proposed research will extend continuous measurements of carbon, water, and energy balance in three tundra ecosystems near Imnavait Creek, Alaska. Ecosystem/atmosphere flux measurements have been collected at these sites via eddy covariance since 2007. Long-term monitoring of hydrology and stream chemistry of Imnavait Creek and depth of thaw in its catchment area will be maintained. Additional measurements to help interpret these data will include water table depth, plant community composition, and vegetation greenness via reflectivity, which is related to leaf area and biomass. Long-term measurements of stream chemistry and discharge are also available at Imnavait, enabling a comprehensive assessment of carbon budgets. All data will be made publicly available and archived at the Arctic Long-Term Ecological Research (LTER) web site, the International Arctic Research Center Data Archive, and the Advanced Cooperative Arctic Data and Information Service (ACADIS).