EAR-PF: Plant Wax Transport and Integration Through the Late Holocene in Guatemala

EAR-PF：危地马拉全新世晚期植物蜡的运输和整合

• 批准号: 1952645
• 负责人: Wesley Parker
• 金额: $ 17.4万
• 依托单位: Parker, Wesley George
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1952645&HistoricalAwards=false
• 关键词: EAR; PF; Plant; Wax; Transport; EAR; PF; Plant; Wax; Transport

Dr. Wesley Parker has been granted an NSF EAR Postdoctoral Fellowship to carry out research and education plans under the mentorship of Dr. Peter Douglas at McGill University. The rainforests of Central America are being lost at an alarming rate, and this has significant impacts on regional precipitation, natural resource availability, and the global carbon cycle. These environmental changes are expected to continue in the future, adversely impacting both human and ecological communities across Central America. Therefore, investigation of changing vegetation and precipitation regimes will complement and expand knowledge surrounding natural variability in tropical forests and constrain the impacts of human activities on these endangered forests. The proposed research will analyze modern plant waxes (abundant and long-lasting hydrocarbon molecules) preserved in sediment cores from lake basins in Guatemala to investigate geospatial transport and integration of plant waxes in the modern tropical forests of Central America. The results will establish a 9,000 year profile of carbon and hydrogen isotope variability that will develop knowledge surrounding long-term changes in vegetation and precipitation. This hypothesis driven research will test the ideas that changing vegetation types in Central America can be assessed through plant wax analysis, and that plant waxes will accurately track climate perturbations in the Western Hemisphere. This project will be conducted in collaboration with local conservation groups in Guatemala to help inform their activities and will be coupled with community education programs in the USA, Canada, and Guatemala. The research is accomplished in two phases. First, the hydrogen and carbon isotopes in long-chained plant waxes (n-alkyl lipids) from modern leaf material and sediments are analyzed using compound specific isotope analyses to characterize plant wax transportation pathways and vegetation balance (C3/C4 plant ratio) in the Lake Izabal and Petén Basins of Guatemala. Then, plant waxes retrieved from sediment cores covering 9,000 years are analyzed to reconstruct changes in vegetation and precipitation through the middle and late Holocene in both basins. These plant wax-derived isotope profiles are then compared to independent proxy data to identify signals of known Holocene climate events (e.g. 8.2 kyr event) and track the magnitude of these signals in tropical Central America. This research enhances the overall quality and applicability of ongoing paleoclimatic research in Central America by generating the first middle and late Holocene hydrogen and carbon isotope profiles for the focal basins. This research can inform policymakers responsible for the generation and implementation of regional conservation and climate adaptation strategies that will benefit human populations, ecological systems, and financial investments in Central America. Additional broader impacts of this research include outreach educational activities in the USA, Canada, and Guatemala. This project received co-funding from the Earth Science section of the Paleo Perspectives on Climate Change program.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.

韦斯利·帕克（Wesley Parker）博士已获得NSF耳朵博士后奖学金，以在麦吉尔大学彼得·道格拉斯（Peter Douglas）的心态下执行研究和教育计划。中美洲的雨林正在以惊人的速度丢失，这对区域降水，自然资源可用性和全球碳循环产生了重大影响。预计将来这些环境变化将在未来继续，对中美洲的人类和生态社区产生不利影响。因此，不断变化的蔬菜和降水制度的投资将补充和扩大围绕热带森林自然变异性的知识，并限制人类活动对这些濒危森林的影响。拟议的研究将分析现代植物蜡（丰富且持久的烃分子）保存在危地马拉湖贝斯的沉积物核心中，以研究中美洲现代热带森林中植物蜡的地理空间运输和整合。结果将建立9，000年的碳和氢同位素变异性，这些变化将发展围绕植被和降水的长期变化的知识。这项假设驱动研究将测试中美洲改变植被类型的想法，可以通过植物蜡分析评估，并且植物蜡将准确跟踪西半球的气候扰动。该项目将与危地马拉的当地保护小组合作进行，以帮助他们的活动信息，并将与美国，加拿大和危地马拉的社区教育计划相结合。该研究分为两个阶段。首先，使用复合特异性同位素分析分析了现代叶子材料和沉积物的长链植物蜡（N-烷基脂质）中的氢和碳同位素，以表征伊扎巴尔湖和Petén盆地的植物蜡蜡传输途径和植被平衡（C3/C4植物平衡（C3/C4植物比率））。然后，分析了从覆盖9，000年的沉积物岩心检索的植物蜡，以重建两个低音中全新世的植被和降水的变化。然后将这些植物蜡衍生的同位素轮廓与独立的代理数据进行比较，以识别已知全新世气候事件（例如8.2 KYR事件）的信号，并跟踪热带中美洲热带信号的大小。这项研究通过为焦点贝斯产生了第一和晚期全新世氢和碳同位素剖面，从而提高了中美洲正在进行的古气候研究的总体质量和适用性。这项研究可以告知政策制定者，负责产生和实施区域保护和气候适应策略，这些策略将使中美洲人口，生态系统和金融投资受益。这项研究的其他广播公司的影响包括美国，加拿大和危地马拉的外展教育活动。该项目从《地球科学》的《气候变化计划》的《地球科学》部分获得了共同的资金。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被认为是通过评估而被视为珍贵的。