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

活性氮物种在对流层光化学中起着重要的作用，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。美国的森林地区是活性氮通过干沉积的主要汇，主要归因于硝酸。本项目利用最新研制的双可调谐半导体激光吸收光谱仪对哈佛森林的二氧化氮和硝酸沉降进行涡旋相关通量测量。其目的是测试关于控制氮氧化物物种之间分配的机制以及它们最终从大气中消除的想法。这些观测将提供有关活性氮收支的季节和年际变化的新信息，并量化酸沉降对森林生态系统的一个重要组成部分。这项研究是与Aerodyne Research，Inc.的Mark Zahniser合作进行的。

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.