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

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.

本项目为位于格陵兰长期研究样地的低北极苔原植被四年被动增温实验，核心目标为测定植物根系对增温的响应，以及该响应在生态系统碳交换中的作用。物候学——即植物地上生长等事件的年度时序与进程——是气候变化生态学中研究较为充分的重要组成部分，但地下部分的物候学研究仍较为匮乏。本研究将估算并对比植物物候学对增温的地上与地下响应，以及二者分别对生态系统功能的贡献，具体为大气与苔原之间的碳交换过程。此外，本研究还将明确哪些植物类群（例如灌木或草本植物）对增温的地下响应更强，且对生态系统碳交换的贡献更大。

本实验将为认识北极对气候变化的预期响应提供全新视角，同时也将完善北极野外实验与观测研究的基础设施。本研究将通过宾夕法尼亚州立大学（Penn State）的少数族裔本科生研究体验项目招募学生，推动代表性不足群体的参与；同时将通过研究样地的夏季野外生态学课程模块，以及宾夕法尼亚州立大学与阿拉斯加大学安克雷奇分校的相关课程，推广研究成果的教育与传播。研究成果将由参与学生与首席研究员发表于同行评议期刊，并在国际学术会议上进行汇报。