EAR-PF: Methane Dynamics in Tidal Salt Marshes: Production and Fate

EAR-PF：潮汐盐沼中的甲烷动力学：产生和命运

• 批准号: 2204489
• 负责人: Margaret Capooci
• 金额: $ 18万
• 依托单位: Capooci, Margaret
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204489&HistoricalAwards=false
• 关键词: EAR; PF; Methane; Dynamics; Tidal

Dr. Margaret Capooci has been awarded an NSF EAR Postdoctoral Fellowship to pursue research and further her education at the University of Georgia under the mentorship of Dr. Amanda Spivak. Dr. Capooci will conduct field experiments to better understand methane dynamics in salt marsh soils. Tidal salt marshes, along with mangrove forests and seagrass beds, store large amounts of carbon within their soils. Marshes can also release carbon through several pathways, including methane emission from the soil to the atmosphere. Since salt marshes play an important role in reducing climate change via carbon storage, it is important to understand how, when, and why salt marshes release methane, a gas that contributes to climate change. Therefore, Dr. Capooci’s research aims to better understand the ways in which methane is produced, consumed, and released from salt marsh soils. These data will help scientists better model salt marsh carbon cycling, as well as provide information to better restore and manage salt marshes for their carbon storage benefits. Dr. Capooci will also involve teachers and undergraduate students from underserved and underrepresented communities in her research, including opportunities for hands-on data collection in the marsh.Methane emissions were thought to be low-to-non-existent in tidal salt marshes due to acetoclastic and hydrogenotrophic methanogenesis being outcompeted by sulfur reducers in the soil. However, researchers have found high methane emissions in marshes, as well as an alternative methanogenesis pathway, methanotrophic methanogensis, that uses non-competitive substrates to produce methane. However, methane emissions are highly variable and difficult to predict in salt marshes. Therefore, resolving the heterogeneity regarding CH4 emissions necessitates a closer look at how methane is produced, consumed, and transported under a variety of scenarios, as well as linking these processes to active microbial communities. A combination of techniques will be used in this project, including mesocosm studies, isotopic tracers, qualitative staple isotope probing, and field surveys to assess how methane dynamics change over temporal (i.e., tidal, seasonal) and spatial (i.e., micrometer to plot scale, depth from soil surface) scales. This project aims to advance scientific knowledge of salt marsh carbon cycling by providing mechanistic information regarding methane dynamics that can be applied across sites and be used to up-scale methane fluxes in model runs, as well as provide data to support natural resource managers in the conservation and restoration of salt marshes.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.

Margaret Capooci博士被授予NSF博士后奖学金，在阿曼达斯皮瓦克博士的指导下在格鲁吉亚大学进行研究和进一步教育。Capooci博士将进行实地实验，以更好地了解盐沼土壤中的甲烷动态。潮汐盐沼，沿着与红树林和海草床，储存大量的碳在其土壤中。沼泽也可以通过几种途径释放碳，包括从土壤向大气中排放甲烷。由于盐沼通过碳储存在减少气候变化方面发挥着重要作用，因此了解盐沼如何，何时以及为什么释放甲烷（一种导致气候变化的气体）非常重要。因此，Capooci博士的研究旨在更好地了解甲烷是如何从盐沼土壤中产生、消耗和释放的。这些数据将帮助科学家更好地模拟盐沼碳循环，并提供信息，以更好地恢复和管理盐沼，以实现其碳储存效益。Capooci博士还将涉及教师和本科生从服务不足和代表性不足的社区在她的研究，包括动手的机会，在沼泽数据收集。甲烷排放量被认为是低至不存在的潮汐盐沼由于乙酸和氢营养甲烷被淘汰的土壤中的硫还原剂。然而，研究人员发现沼泽中的甲烷排放量很高，以及另一种甲烷生成途径，甲烷营养型甲烷生成，使用非竞争性底物来产生甲烷。然而，盐沼的甲烷排放量变化很大，难以预测。因此，解决甲烷排放的异质性需要更仔细地研究甲烷在各种情景下是如何产生、消耗和运输的，以及将这些过程与活跃的微生物群落联系起来。该项目将使用多种技术，包括围隔研究、同位素示踪剂、定性主要同位素探测和实地调查，以评估甲烷动态如何随时间变化（即，潮汐的，季节的）和空间的（即，从土壤表面的深度）尺度。该项目旨在通过提供有关甲烷动力学的机械信息来推进盐沼碳循环的科学知识，这些信息可以应用于各个地点，并用于在模型运行中扩大甲烷通量，并提供数据来支持自然资源管理者保护和恢复盐沼。该奖项反映了NSF的法定使命，并通过使用基金会的学术价值和更广泛的影响审查标准。