揭示了低估的酸 (HONO) 的直接排放量
Qian Zhang1,2, Pengfei Liu3, Yan Wang1
1Sino-French Research Institute for Ecology and Environment, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
概括
直接排放,包括来自畜牧业的直接排放,是大气中酸 (HONO) 的主要来源,严重影响空气质量. 这项研究揭示了HONO HONO.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 同位素地球化学 同位素地球化学
背景情况:
- 气态酸 (HONO) 是热层中基 (OH) 的关键前体.
- 与二次来源相比,HONO的直接排放在历史上被低估了.
- 了解HONO源对于准确的空气质量建模至关重要.
研究的目的:
- 开发和应用同位素指纹 (δ15N和δ18O) 来识别和量化直接HONO排放源.
- 调查直接HONO排放对大气HONO预算的贡献,特别是在农业地区.
- 评估直接HONO排放对北中国平原空气质量的影响.
主要方法:
- 为六个直接的HONO排放源开发 δ15N和 δ18O同位素指纹.
- 一项为期一年的实地研究,测量了农村和城市地区大气中的HONO同位素组成.
- HONO预算分析包括农业排放和化学运输模型模拟.
主要成果:
- 畜牧业被确定为HONO的重要,以前被忽视的直接来源.
- 直接的HONO排放被发现占农村地区季节性HONO生产的39-45%.
- 大气中HONO同位素的空间和时间变化与直接排放源有关.
结论:
- 直接的HONO排放在大气中的HONO产量中发挥的作用比以前被认为的要大得多.
- 同位素指纹为追踪大气中的活性气提供了强大的工具.
- 调查结果强调了农业实践在HONO排放和空气质量管理方面的重要性.
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