Collaborative Research: EAR-Climate: Hydraulic and Hydrologic Regulation of Greenhouse Gas Emissions from Forest Soils and Trees and Detection With Radon As A Novel Tracer

合作研究：EAR-气候：森林土壤和树木温室气体排放的水力和水文调节以及用氡作为新型示踪剂进行检测

• 批准号: 2210783
• 负责人: James Megonigal
• 金额: $ 30.75万
• 依托单位: Smithsonian Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2210783&HistoricalAwards=false
• 关键词: Collaborative; Research; EAR; Climate; Hydraulic

The goals of this project are to better understand the role of trees in the global water and methane cycles and to attract elementary-school age students to environmental science through hands-on activities about water and trees. Methane is a potent greenhouse gas, causing about 30 times as much global warming per molecule as carbon dioxide. It is currently known that methane can be emitted from the trunks of trees, but it is unknown if the methane originates in the soil and is transported into the tree along with tree water uptake from below ground, or if the methane originates inside the tree. Understanding what water and environment factors influence methane emissions from trees can improve climate predictions and may help people manage forests and forested wetlands deliberately to reduce their natural methane emissions. The project will also work with a local elementary school serving talented and gifted students primarily from underrepresented groups (Black, Latinx). About 200 second-grade students will visit American University, where they will learn about watersheds, trees, and sustainability and participate in activities to develop a science identity.This research will use radon as a tracer of the movement of water and gases through trees. Radon is an established tool for studying water flows and gas exchange in the ocean, estuaries, rivers, soil, and groundwater. Radon, methane, and water fluxes from trees will be simultaneously measured across a wetland-upland gradient to determine whether the methane emitted from trees comes from soil water or is produced within the tree. Soil moisture, water potential, soil methane and radon concentrations, water table height, stomatal conductance, and sap flow will be measured concurrently to delineate the relationships between tree physiology, water flows, and stem gas emissions and to distinguish topographic effects. Field data will be used to develop numerical models that simulate dynamic gas transport through the soil-plant-atmosphere continuum, account for both dissolved gas and bubbles, and include both daytime and nighttime transient water potential gradients and transport. Finally, the results will be scaled up to assess how direct and indirect effects of climate change (e.g., temperature increase, sea level rise, changes in precipitation patterns, soil moisture, and tree water use, shift of some coastal forests from upland to wetland) may affect tree methane emissions.This award is co-funded by the Hydrologic Sciences and Instrumentation and Facilities programs in the Division of Earth Sciences, as well as the Ecosystem Science program in the Division of Environmental Biology.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.

该项目的目标是更好地了解树木在全球水和甲烷周期中的作用，并通过对水和树木的动手活动吸引小学时代的学生进入环境科学。甲烷是一种有效的温室气体，每个分子的全球变暖是二氧化碳的30倍。目前众所周知，甲烷可以从树干中发出，但是甲烷是否起源于土壤，并与从地下下面的树水吸收一起运输到树上，或者甲烷是否起源于树内。了解哪些水和环境因素会影响树木的甲烷排放可以改善气候预测，并可能有助于人们管理森林和森林湿地，以减少其天然甲烷排放。该项目还将与当地的小学合作，为有才华和有天赋的学生提供主要代表性不足的团体（Black，Latinx）。大约200名二年级学生将参观美国大学，在那里他们将了解流域，树木和可持续性，并参与开发科学身份的活动。这项研究将用ra作为水和气体通过树木运动的示踪剂。 ra是一种研究水流和气体交换的既定工具，在海洋，河口，河流，土壤和地下水中。将同时测量树木中的ra，甲烷和水通量。将同时测量土壤水分，水潜能，土壤甲烷和ra浓度，水桌高度，气孔电导和SAP流量，以描绘树生理学，水流和茎气排放之间的关系并区分地形效应。现场数据将用于开发数值模型，以模拟通过土壤植物 - 大气连续体的动态气体传输，既说明了溶解的气体和气泡，又包括白天和夜间瞬时水潜在的潜在水潜在梯度和运输。 Finally, the results will be scaled up to assess how direct and indirect effects of climate change (e.g., temperature increase, sea level rise, changes in precipitation patterns, soil moisture, and tree water use, shift of some coastal forests from upland to wetland) may affect tree methane emissions.This award is co-funded by the Hydrologic Sc​​iences and Instrumentation and Facilities programs in the Division of Earth Sciences, as well as the Ecosystem Science program in the Division该奖项反映了NSF的法定使命，并被认为是值得通过基金会的知识分子优点和更广泛的影响审查标准的评估来支持的。