EAR-PF: Biomass burning in the terrestrial Arctic during past warm periods: New insights from organic biomarkers in Lake El'gygytgyn (Siberia)

EAR-PF：过去温暖时期北极陆地生物质燃烧：来自埃尔吉吉特金湖（西伯利亚）有机生物标志物的新见解

• 批准号: 1855281
• 负责人: William Daniels
• 金额: $ 17.4万
• 依托单位: Daniels, William C
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1855281&HistoricalAwards=false
• 关键词: EAR; PF; Biomass; burning; terrestrial

Dr. William Daniels has been granted an NSF EAR Postdoctoral Fellowship to carry out research and education plans at the University of Massachusetts Amherst. The research will use geologic records of past wildfires to investigate factors that might impact future fire prevalence in the Arctic tundra. Wildfires play an important role in forest ecology, contribute to the global carbon cycle, and can interfere with human activities. In the Arctic, wildfires are historically rare, but their frequency is increasing as climate warms. This recent trend is surprising given that existing paleofire records demonstrate that a cold and dry climate is more conducive to burning then a warm and wet climate. Ancient lake sediments from the Siberian Arctic will be analyzed for evidence of past wildfires during time periods that span a wide range of climatic conditions to better understand climate-wildfire linkages. The study will test the ideas that permafrost, aridity, and vegetation can influence the relationship between temperature and tundra wildfires. The research will be coupled with community education activities, including teaching environmental science camps for local youth in Massachusetts and Arctic Alaska.The proposed research will use organic geochemical proxies in a Lake El'gygytgyn sediment core covering 3.6 million years to reconstruct variations in Arctic biomass burning over the Plio-Pleistocene. Levoglucosan and polycyclic aromatic hydrocarbons, molecular byproducts of biomass burning, will be compared with independently-derived paleoclimate reconstructions during the mid-Pliocene Warm Period (3.02-3.26 Ma; a key analog for future global climate) and during the Superinterglacial Marine Isotope Stage 31 (1.06-1.08 Ma). Results will provide a direct comparison of glacial-interglacial variability during the Pliocene versus the Pleistocene to test if permafrost and vegetation shifts under prolonged warming could lead to profoundly different fire systematics. The study will further develop and test molecular fire proxies needed to generate additional paleofire records.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.

William Daniels 博士已获得 NSF EAR 博士后奖学金，在马萨诸塞大学阿默斯特分校开展研究和教育计划。该研究将利用过去野火的地质记录来调查可能影响北极苔原未来火灾发生率的因素。野火在森林生态中发挥着重要作用，有助于全球碳循环，并会干扰人类活动。在北极，野火历史上很少见，但随着气候变暖，野火的频率正在增加。鉴于现有的古火记录表明寒冷干燥的气候比温暖潮湿的气候更有利于燃烧，最近的趋势令人惊讶。将分析西伯利亚北极的古代湖泊沉积物，以寻找过去在各种气候条件下发生的野火的证据，以更好地了解气候与野火的联系。该研究将检验永久冻土、干旱和植被会影响温度与苔原野火之间关系的观点。该研究将与社区教育活动相结合，包括为马萨诸塞州和阿拉斯加北极地区的当地年轻人举办环境科学营教学。拟议的研究将使用覆盖 360 万年的 El'gygytgyn 湖沉积物核心中的有机地球化学替代物来重建北极生物量的变化燃烧于上更新世。左旋葡聚糖和多环芳烃是生物质燃烧的分子副产品，将与上新世中期温暖期（3.02-3.26 Ma；未来全球气候的关键模拟）和上冰期海洋同位素阶段 31 期间独立得出的古气候重建进行比较（1.06-1.08 Ma）。结果将提供上新世与更新世期间冰川-间冰期变异性的直接比较，以测试长期变暖下的永久冻土和植被变化是否会导致截然不同的火灾系统。该研究将进一步开发和测试生成额外古火记录所需的分子火代理。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。