Collaborative Research: Understanding Emission Sources and Sinks of Nitrous Acid in North American Forests

合作研究：了解北美森林亚硝酸的排放源和汇

• 批准号: 2243203
• 负责人: Jeffrey Geddes
• 金额: $ 5.56万
• 依托单位: Trustees of Boston University
• 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: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2243203&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; Emission; Sources

This project focuses on land-atmosphere interactions and the mechanisms by which nitrous acid (HONO) and other nitrogen oxides emitted from soils influence the oxidizing capacity of the atmosphere. The experimental plans include the use of growth chambers under controlled conditions combined with field data to study the uptake of HONO onto leaves from a range of tree species that dominate major forested regions across North America. Since HONO is not well represented in chemical transport models, improvements in understanding HONO sources and sinks are expected to have important implications for improving air quality models and for determining the lifetime of some greenhouse gases, such as methane, in the atmosphere.This effort combines expertise in atmospheric chemistry, microbial ecology, and modeling with unique analytical capabilities for measuring HONO soil emissions. The central hypothesis of this proposal is that variations in below-canopy hydrogen oxide radical (HOx) cycling and ozone levels in forested regions are driven by the variability of soil emissions of HONO (SHONO) and nitrogen oxide (NO) (SNO), that depend on season, edaphic properties, aboveground vegetation surfaces, and belowground nitrogen cycling that is mediated by microbe-plant interactions. Preliminary data show that high SNO has a significant impact on below canopy HOx in a forested environment, that NOy (the sum of reactive nitrogen oxides) fluxes are linked to forest composition, and that spatial variability in NOy fluxes can be mapped across the continental U.S. using forest inventory plots. The objectives of the research are to: (1) Establish geospatial trends in SHONO across U.S. forests; (2) Carry out field campaigns to measure SHONO in mixed deciduous forests; and (3) Quantify uptake of HONO by leaf and soil surfaces.The project will support a full-time postdoctoral researcher and a graduate student who will receive training in state-of-the science analytical and modeling methods. Undergraduate students will be directly involved in the research as part of Indiana University’s Groups Summer Research Experience Program, which gives entering first-year students research experience and skills to excel in STEM majors.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.

该项目着重于土地大气相互作用以及一酸（Hono）和其他从土壤中发出的氮氧化物影响大气的氧化能力的机制。实验计划包括在受控条件下与现场数据结合使用生长室来研究Hono的吸收，从北美地区主要森林区域的一系列树种中的叶子吸收。由于HONO在化学运输模型中没有很好的代表性，因此预计了解Hono来源和水槽的改进对改善空气质量模型和确定大气中的某些温室气体（例如甲基化）的寿命具有重要意义。这与大气化学，微生物生态学，与独特的分析能力进行测量的Hono hono土壤土壤的专家结合了专家。 The central hypothesis of this proposal is that variations in Below-canopy hydrogen oxide radical (HOx) cycling and ozone levels in forested regions are driven by the variability of soil emissions of HONO (SHONO) and nitrogen oxide (NO) (SNO), that depends on season, edaphic properties, aboveground vegetation surfaces, and belowground nitrogen cycling that is mediated by microbe-plant互动。初步数据表明，高SNO在森林环境中对下面的冠层HOX具有重大影响，Noy（反应性氮氧化物的总和）与森林组成有关，并且可以使用森林库存在美国连续的美国范围内映射Noy Flux的空间可变性。该研究的目标是：（1）在美国森林中建立肖诺的地理空间趋势； （2）进行现场运动，以测量混合落叶林中的shono； （3）通过叶子和土壤表面量化HONO的吸收。该项目将支持全日制的博士后研究员和研究生，他们将接受科学分析和建模方法的培训。本科生将直接参与这项研究，这是印第安纳大学夏季研究经验计划的一部分，该课程为进入第一年的学生研究经验和技能在STEM专业的专业中表现出色。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的审查标准来通过评估来获得支持的。