Collaborative Research: Measurements of Gaseous Nitric Acid, Nitrogen Dioxide, and Atmospheric Nitrogen Deposition Fluxes in Two Mixed-Hardwood Forests

活性氮在对流层光化学中起着重要作用，控制臭氧的形成，影响羟基自由基的浓度，并有助于酸和营养物质的沉积。美国森林地区是活性氮通过干沉降的主要汇，主要归因于硝酸。 本计画利用一台新开发之双波长可调二极体雷射吸收光谱仪，于哈佛森林进行二氧化氮及硝酸沉降之涡动相关通量量测。 其目标是测试有关控制氮氧化物物种之间的分配及其最终从大气中去除的机制的想法。 这些观测将产生关于活性氮收支的季节性和年际变化的新信息，并量化森林生态系统酸沉降的重要组成部分。 本研究是与Aerodyne Research，Inc.的Mark Zahniser合作完成的。

Reactive nitrogen species play an important role in tropospheric photochemistry, controlling ozone formation, affecting the concentration of hydroxyl radicals, and contributing to deposition of acids and nutrients. Forested areas in the United States present a major sink for reactive nitrogen through dry deposition, attributed mainly to nitric acid. This project utilizes a newly developed a newly developed dual tunable diode laser absorption spectrometer to make eddy correlation flux measurement of nitrogen dioxide and nitric acid deposition at Harvard Forest. The goal is to test ideas about mechanisms controlling partitioning among of nitrogen oxide species and their ultimate removal from the atmosphere. The observations will produce new information on seasonal and interannual variability in the reactive nitrogen budget, and quantify an important component of acid deposition to forest ecosystems. This research is a collaborative effort with Mark Zahniser, Aerodyne Research, Inc.