Collaborative Research: Linking belowground phenology and ecosystem function in a warming Arctic

北极变暖中地下物候与生态系统功能的联系？（E. Post， PI）本项目在格陵兰岛的一个长期研究地点对低北极苔原植被进行了为期四年的被动变暖实验，主要目的是测量植物根系对变暖的响应及其在生态系统碳交换中的作用。物候学，即地表植物生长等事件的年度时间和进程，是气候变化生态学的一个重要组成部分，但对地下的研究仍然不足。本研究将估算和比较地表和地下植物物候对变暖的响应及其各自对生态系统功能的贡献，特别是大气与冻土带之间的碳交换。它将进一步确定哪些植物类型（如灌木或草）对变暖表现出更大的地下响应和对生态系统碳交换的贡献。这项实验将对北极对气候变化的预期反应产生新的见解，这也将扩大北极实地实验和观测研究的基础设施。这项研究将通过宾夕法尼亚州立大学招收学生来促进代表性不足的群体的参与。并通过研究地点的夏季野外生态学模块以及宾夕法尼亚州立大学和阿拉斯加-安克雷奇大学的课程，促进其成果的教育和传播。研究结果也将发表在同行评议的期刊上，并由参与研究的学生和主要研究人员在国际会议上发表。

Linking Belowground Phenology and Ecosystem Function in a Warming Arctic ? Non-technical abstract (E. Post, PI)This project comprises a four-year, passive warming experiment of low-Arctic tundra vegetation at a long-term study site in Greenland, with the primary aim of measuring the response of plant roots to warming, and the role of this response in ecosystem carbon exchange. Phenology, the annual timing and progression of events such as aboveground plant growth, is a well-studied an important component of the ecology of climate change, but remains under-studied belowground. This study will estimate and compare above- and belowground responses of plant phenology to warming and their respective contributions to ecosystem function, specifically the exchange of carbon between the atmosphere and tundra. It will furthermore determine which plant types, e.g., shrubs or grasses, show the greater belowground response to warming and contribution to ecosystem carbon exchange. Novel insights into the expected response of the Arctic to climate change will emerge from this experiment, which will also expand the infrastructure for field-based experimental and observational research in the Arctic. This research will promote the involvement of under-represented groups by recruitment of students through Penn State?s Minority Undergraduate Research Experience program, and promote education and dissemination of its results through a summer field ecology module at the study site and in courses at Penn State and the University of Alaska-Anchorage. Results will also be published in peer-reviewed journals and presented at international conferences by participating students and the Principal Investigators.