Dissertation Research: Controls on Methane Flux from Arctic Tundra

论文研究：北极苔原甲烷通量的控制

• 批准号: 1311089
• 负责人: David Lipson
• 金额: $ 1.94万
• 依托单位: San Diego State University Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1311089&HistoricalAwards=false
• 关键词: Dissertation; Research; Controls; Methane; Flux

High-latitude ecosystems are among the most sensitive to accelerating climate change, with some of the highest rates of temperature increase and altered hydrological patterns. The rich carbon reserves locked in northern soils are increasingly prone to being released into the atmosphere as methane, a powerful greenhouse gas that, as atmospheric concentrations increase, is liable to further increase the speed of warming. The two major environmental factors that affect the amount of methane being made and released from natural wetland ecosystems are (1) how wet the soil is, and (2) how warm the soil is, but little is known about how these factors interact during seasonal transition periods like late spring, when soils thaw and lose snow cover. This project uses a portable greenhouse gas analyzer to measure methane gas emissions from a northern Finnish mire during the 2013 spring transition period and summer growing season, using snow-melting and soil manipulation experiments to determine the influence of these variables on methane emission rates.Precisely because they are experiencing climate changes at faster rates than the rest of the planet, methane studies in high-latitude systems are critical to our understanding of future climate dynamics. This research will contribute not only to scientific knowledge of methane cycling in northern wetlands, but also to improving global climate models that inform international climate change policymaking. Moreover, this research recognizes that climate change is not merely a national issue, and facilitates trans-national comparisons with the authors? ongoing study of Alaskan wetlands. The field work will include the participation of a PolarTREC volunteer, an American middle school science teacher, which will provide multiple outreach avenues for informing young Americans about this research. Additional outreach and field-based teaching opportunities will be conducted, both in Finland and America.

高纬度生态系统是对加速气候变化最敏感的生态系统之一，其中一些地区的气温上升速度最快，水文模式也发生了变化。北方土壤中丰富的碳储备越来越容易以甲烷的形式释放到大气中，甲烷是一种强大的温室气体，随着大气浓度的增加，可能会进一步加快变暖的速度。 影响自然湿地生态系统产生和释放的甲烷量的两个主要环境因素是（1）土壤的湿润程度，以及（2）土壤的温暖程度，但人们对这些因素在季节期间如何相互作用知之甚少。过渡时期，如晚春，土壤融化并失去积雪。该项目使用便携式温室气体分析仪测量芬兰北部沼泽地在2013年春季过渡期和夏季生长季期间的甲烷气体排放量，通过融雪和土壤处理实验来确定这些变量对甲烷排放率的影响。由于高纬度系统正在以比地球其他地区更快的速度经历气候变化，因此高纬度系统中的甲烷研究对于我们了解未来气候动态至关重要。这项研究不仅有助于增进北部湿地甲烷循环的科学知识，而且有助于改进为国际气候变化政策制定提供信息的全球气候模型。此外，这项研究认识到气候变化不仅仅是一个国家问题，并有助于与作者进行跨国比较？正在进行的阿拉斯加湿地研究。现场工作将包括一名 PolarTREC 志愿者、一名美国中学科学老师的参与，这将为向美国年轻人宣传这项研究提供多种外展途径。将在芬兰和美国提供额外的外展和实地教学机会。