Collaborative Research: Vegetation And Ecosystem Impacts On Permafrost Vulnerability

合作研究：植被和生态系统对永久冻土脆弱性的影响

• 批准号: 1417700
• 负责人: Susan Natali
• 金额: $ 56.2万
• 依托单位: Woodwell Climate Research Center, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417700&HistoricalAwards=false
• 关键词: Collaborative; Research; Vegetation; Ecosystem; Impacts

NontechnicalRealistic representations of heat exchange in permafrost ecosystems are necessary for accurate predictive understanding of the permafrost carbon feedback under future climate scenarios. This project will provide a quantitative pan-arctic assessment of the effects of vegetation and landscape characteristics on permafrost thermal regimes. By working across ecosystems, landscape characteristics, and regions, the research will identify broad trends, and intensive energy balance sites will provide a mechanistic study of ecosystem impacts on permafrost response to climate change. The impacts of this study will be enhanced through integration of research results into regional and site-specific permafrost models and synthesis activities that will examine ecosystem impacts on energy balance and permafrost vulnerability to climate change. This work will have broad impacts on the scientific community and general public because it brings together important issues in the global environment and raises awareness of the connection between ecosystem dynamics and permafrost thaw. The proposed project will provide training opportunities for undergraduate students through collaboration between the researchers and an NSF funded field research experience for undergraduates. The researchers will mentor several students as part of this proposed work and will also teach two arctic system science courses at a predominantly undergraduate institution. This project will enhance scientific understanding through continued work with education centers, local communities and, in particular, with teachers and outreach coordinators. TechnicalSignificant declines in permafrost distribution are expected as the climate warms, but large uncertainties remain in determining the fate of permafrost under future climate scenarios. These uncertainties are driven, in large part, by vegetation and ecosystem properties that modulate the effect of climate on permafrost temperatures. Long-term monitoring of permafrost temperatures demonstrates the importance of these local conditions, yet there has been no pan-arctic effort to measure ecological and landscape variables in concert with permafrost temperature monitoring. This project will use a combination of field and remotely-sensed data to address the question of how vegetation and landscape factors modulate permafrost temperature response to climate change. To address this question the researchers will couple an extensive pan-arctic assessment of vegetation-permafrost dynamics with an intensive study of shrub and tree canopy cover effects on ecosystem energy balance. The first component of this research will be conducted at long-term permafrost temperature monitoring sites in Siberia and Alaska, and the second component, the vegetation-energy balance sites that will be established as part of this proposal, will be conducted at a shrub-tree canopy cover gradient in Siberia, where most permafrost regions are located. These intensively studied energy balance sites will provide an improved mechanistic understanding of the effects of ecosystem components, and interactions among these components, on ecosystem energy balance and permafrost vulnerability to climate change. This mechanistic knowledge will, in turn, support interpretation of broad patterns observed through a pan-arctic sampling of the permafrost temperature monitoring sites.

永久冻土生态系统中热交换的非技术现实表示对于准确预测了解未来气候情景下的永久冻土碳反馈是必要的。该项目将对植被和景观特征对永久冻土热状况的影响进行定量的泛北极评估。通过跨生态系统、景观特征和区域的工作，该研究将确定广泛的趋势，而密集的能量平衡站点将提供生态系统对永久冻土对气候变化响应的影响的机制研究。这项研究的影响将通过将研究成果纳入区域和特定地点的永久冻土模型和综合活动来增强，这些模型和综合活动将检查生态系统对能量平衡和永久冻土对气候变化的脆弱性的影响。这项工作将对科学界和公众产生广泛影响，因为它汇集了全球环境中的重要问题，并提高了人们对生态系统动态与永久冻土融化之间联系的认识。拟议的项目将通过研究人员之间的合作以及美国国家科学基金会资助的本科生实地研究经验，为本科生提供培训机会。作为这项拟议工作的一部分，研究人员将指导几名学生，并将在一个以本科为主的机构教授两门北极系统科学课程。该项目将通过与教育中心、当地社区，特别是与教师和外展协调员的持续合作，增强科学理解。技术随着气候变暖，预计永久冻土分布将显着下降，但在未来气候情景下确定永久冻土的命运仍然存在很大的不确定性。这些不确定性在很大程度上是由调节气候对永久冻土温度影响的植被和生态系统特性造成的。对永久冻土温度的长期监测表明了这些当地条件的重要性，但目前还没有泛北极地区努力测量与永久冻土温度监测相结合的生态和景观变量。该项目将结合实地和遥感数据来解决植被和景观因素如何调节永久冻土温度对气候变化的响应的问题。为了解决这个问题，研究人员将对植被-永久冻土动态进行广泛的泛北极评估，同时深入研究灌木和树冠覆盖对生态系统能量平衡的影响。这项研究的第一部分将在西伯利亚和阿拉斯加的长期永久冻土温度监测点进行，第二部分，即作为该提案的一部分建立的植被-能量平衡点，将在大多数永久冻土区所在的西伯利亚的灌木树冠覆盖梯度处进行。这些深入研究的能量平衡站点将有助于更好地理解生态系统组成部分以及这些组成部分之间的相互作用对生态系统能量平衡和永久冻土对气候变化的脆弱性的影响。反过来，这种机械知识将支持对通过对永久冻土温度监测点进行泛北极采样所观察到的广泛模式的解释。

项目成果

Variation in Fine Root Characteristics and Nutrient Dynamics Across Alaskan Ecosystems

阿拉斯加生态系统细根特征和养分动态的变化

• DOI: 10.1007/s10021-020-00583-8
• 发表时间: 2020
• 期刊: Ecosystems
• 影响因子: 3.7
• 作者: McCulloch, Lindsay A.;Kropp, Heather;Kholodov, Alexander;Cardelús, Catherine L.;Natali, Susan M.;Loranty, Michael M.
• 通讯作者: Loranty, Michael M.

Spatial variation in vegetation productivity trends, fire disturbance, and soil carbon across arctic-boreal permafrost ecosystems

• DOI: 10.1088/1748-9326/11/9/095008
• 发表时间: 2016-09
• 期刊: Environmental Research Letters
• 影响因子: 6.7
• 作者: M. Loranty;W. Lieberman-Cribbin;L. Berner;S. Natali;S. Goetz;H. Alexander;A. Kholodov

Variability in above- and belowground carbon stocks in a Siberian larch watershed

西伯利亚落叶松流域地上和地下碳储量的变化

• DOI: 10.5194/bg-14-4279-2017
• 发表时间: 2017
• 期刊: Biogeosciences
• 影响因子: 4.9
• 作者: Webb, Elizabeth E.;Heard, Kathryn;Natali, Susan M.;Bunn, Andrew G.;Alexander, Heather D.;Berner, Logan T.;Kholodov, Alexander;Loranty, Michael M.;Schade, John D.;Spektor, Valentin
• 通讯作者: Spektor, Valentin

Shallow soils are warmer under trees and tall shrubs across Arctic and Boreal ecosystems

• DOI: 10.1088/1748-9326/abc994
• 发表时间: 2020-11
• 期刊: Environmental Research Letters
• 影响因子: 6.7
• 作者: Heather Kropp;M. Loranty;S. Natali;A. Kholodov;A. Rocha;I. Myers-Smith;Benjamin W. Abbott;J. Abermann;E. Blanc‐Betes;D. Blok;G. Blume‐Werry;J. Boike;A. Breen;Sean M. P. Cahoon;C. Christiansen;T. Douglas;H. Epstein;G. Frost;M. Goeckede;T. Høye;S. Mamet;J. O’Donnell;D. Olefeldt;G. Phoenix;V. Salmon;A. Sannel;Sharon L. Smith;O. Sonnentag;L. Vaughn;M. Williams;B. Elberling;L. Gough;J. Hjort;P. Lafleur;E. Euskirchen;M. Heijmans;E. Humphreys;H. Iwata;B. Jones;T. Jorgenson;I. Grünberg;Yongwon Kim;J. Laundre;M. Mauritz;A. Michelsen;G. Schaepman‐Strub;K. Tape;M. Ueyama;B. Lee;K. Langley;M. Lund

Environmental constraints on transpiration and stomatal conductance in a Siberian Arctic boreal forest: TRANSPIRATION IN AN ARCTIC BOREAL FOREST

西伯利亚北极北方森林蒸腾作用和气孔导度的环境限制：北极北方森林的蒸腾作用

• DOI: 10.1002/2016jg003709
• 发表时间: 2017
• 期刊: Journal of Geophysical Research: Biogeosciences
• 作者: Kropp, Heather;Loranty, Michael;Alexander, Heather D.;Berner, Logan T.;Natali, Susan M.;Spawn, Seth A.
• 通讯作者: Spawn, Seth A.