土壤化学过程对大气含氮活性物种影响机制的研究

含氮化合物在大气化学中起着非常重要的作用，土壤是大气含氮化合物的重要来源，但是土壤含氮物种的释放和生成机理机制的研究相当匮乏。本研究针对不同的农业活动，在河北望都县和北京城区同时开展实际大气中重要含氮气态污染物、O3、PAN以及颗粒物中关键组分的对比观测研究；同时，采用双开顶动态箱技术，综合观测NO、NO2、NH3和HONO在不同土壤与大气之间的交换通量；采用流动管土壤模拟研究手段，结合烟雾箱和漫反射红外光谱等反应器，研究土壤大气含氮活性物种的关键释放和转化机制，为模型模拟提供微观机制及动力学参数；利用箱式模型验证实验室模拟得到的机理机制的准确性，确定不同环境下这些含氮活性物种的迁移转化过程及对空气污染的影响。本研究有助于揭示含氮物种的污染来源，阐明土壤含氮物种的释放和生成机制；提供不同土壤类型活性含氮物种的排放通量，评估土壤对大气含氮物种的贡献，对污染控制具有重要指导意义。

Reactive Nitrogen Species (RNSs) play a very important role in the atmospheric chemistry. Soil is a major source of RNSs in the atmosphere. However, the formation processes of RNSs from soil are not completely understood. In this project, field measurements of RNSs and many other chemical compounds will be conducted at the urban of Beijing and agricultural region of Wangdu, Hebei province. A twin open top chambers method will be used to measure NO, NO2, NH3 and HONO exchange flux between different types soil and the air. The mechanism of RNSs released from soil will be studied by smog chamber and flow tube systems. Box model will be used to verify the mechanism of these transformation processes. The influence of soil types on released RNSs is quantified, and the effect of soil process on environmental and air quality will be examined. This project can help to indicate the sources of RNSs, provide the mechanism of the formation of RNSs. Furthermore, this research will give an important basis scientific guidence for reducing atmospheric pollution in China.