Collaborative Research: Reconstructing Late Holocene Ecosystem and Climate Shifts from Peat Records in the Western Antarctic Peninsula

合作研究：根据南极半岛西部的泥炭记录重建全新世晚期生态系统和气候变化

• 批准号: 1745068
• 负责人: Robert Booth
• 金额: $ 38.44万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1745068&HistoricalAwards=false
• 关键词: Collaborative; Research; Reconstructing; Late; Holocene

Warming on the western Antarctic Peninsula in the later 20th century has caused widespread changes in the cryosphere (ice and snow) and terrestrial ecosystems. These recent changes along with longer-term climate and ecosystem histories will be deciphered using peat deposits. Peat accumulation can be used to assess the rate of glacial retreat and provide insight into ecological processes on newly deglaciated landscapes in the Antarctic Peninsula. This project builds on data suggesting recent ecosystem transformations that are linked to past climate of the western Antarctic Peninsula and provide a timeline to assess the extent and rate of recent glacial change. The study will produce a climate record for the coastal low-elevation terrestrial region, which will refine the major climate shifts of up to 6 degrees C in the recent past (last 12,000 years). A novel terrestrial record of the recent glacial history will provide insight into observed changes in climate and sea-ice dynamics in the western Antarctic Peninsula and allow for comparison with off-shore climate records captured in sediments. Observations and discoveries from this project will be disseminated to local schools and science centers. The project provides training and career development for a postdoctoral scientist as well as graduate and undergraduate students.The research presents a new systematic survey to reconstruct ecosystem and climate change for the coastal low-elevation areas on the western Antarctic Peninsula (AP) using proxy records preserved in late Holocene peat deposits. Moss and peat samples will be collected and analyzed to generate a comprehensive data set of late-Holocene climate change and ecosystem dynamics. The goal is to document and understand the transformations of landscape and terrestrial ecosystems on the western AP during the late Holocene. The testable hypothesis is that coastal regions have experienced greater climate variability than evidenced in ice-core records and that past warmth has facilitated dramatic ecosystem and cryosphere response. A primary product of the project is a robust reconstruction of late Holocene climate changes for coastal low-elevation terrestrial areas using multiple lines of evidence from peat-based biological and geochemical proxies, which will be used to compare with climate records derived from marine sediments and ice cores from the AP region. These data will be used to test several ideas related to novel peat-forming ecosystems (such as Antarctic hairgrass bogs) in past warmer climates and climate controls over ecosystem establishment and migration to help assess the nature of the Little Ice Age cooling and cryosphere response. The chronology of peat cores will be established by radiocarbon dating of macrofossils and Bayesian modeling. The high-resolution time series of ecosystem and climate changes will help put the observed recent changes into a long-term context to bridge climate dynamics over different time scales.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

20世纪后期南极半岛西部变暖导致冰冻圈（冰雪）和陆地生态系统发生广泛变化。这些最近的变化以及长期的气候和生态系统历史将利用泥炭沉积物来破译。泥炭积累可用于评估冰川退缩的速度，并深入了解南极半岛新消融景观的生态过程。该项目建立在表明与南极半岛西部过去的气候相关的近期生态系统转变的数据基础上，并提供了评估近期冰川变化的程度和速度的时间表。该研究将产生沿海低海拔陆地地区的气候记录，该记录将细化最近（过去12,000年）高达6摄氏度的主要气候变化。近期冰川历史的新颖陆地记录将有助于深入了解南极半岛西部气候和海冰动态的观测变化，并可与沉积物中捕获的近海气候记录进行比较。该项目的观察结果和发现将传播给当地学校和科学中心。该项目为博士后科学家以及研究生和本科生提供培训和职业发展。该研究提出了一项新的系统调查，利用代理记录重建南极半岛西部沿海低海拔地区的生态系统和气候变化保存于全新世晚期泥炭矿床中。将收集并分析苔藓和泥炭样本，以生成全新世晚期气候变化和生态系统动态的综合数据集。目标是记录和了解全新世晚期亚太地区西部景观和陆地生态系统的转变。可检验的假设是，沿海地区经历了比冰芯记录中所证明的更大的气候变化，并且过去的温暖促进了巨大的生态系统和冰冻圈响应。该项目的主要产品是利用基于泥炭的生物和地球化学替代物的多种证据，对沿海低海拔陆地地区全新世晚期的气候变化进行稳健的重建，这些证据将用于与海洋沉积物和气候记录进行比较。来自亚太地区的冰芯。这些数据将用于测试与过去温暖气候中新型泥炭形成生态系统（例如南极毛草沼泽）以及对生态系统建立和迁移的气候控制相关的几个想法，以帮助评估小冰河时代冷却和冰冻圈响应的性质。泥炭岩芯的年代学将通过大型化石的放射性碳测年和贝叶斯建模来确定。生态系统和气候变化的高分辨率时间序列将有助于将观察到的近期变化纳入长期背景，以弥合不同时间尺度的气候动态。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准。