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在中国东南部一个典型地区控制空气污染后,湿酸盐沉积的来源成分的变化

Jingwen Huang¹, Lingyun Peng¹, Chaopu Ti¹

¹State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China.

Journal of environmental management

|July 2, 2024

概括

中国中国中国中国.

科学领域:

环境科学环境科学
大气化学大气化学
生态生态学生态生态学

背景情况:

中国实施控制氧化 (NOx) 排放的政策旨在减轻酸 (NO3-N) 沉积的不利影响.
了解湿NO3-N沉积的变化及其在这些控制措施下的来源对于环境管理至关重要.

研究的目的:

根据空气污染控制政策,调查中国东南部湿NO3-N沉积及其来源的变化.
评估排放控制策略对大气气循环和沉积的有效性.

主要方法:

2014-2015年和2021-2022年在中国东南部的降水化学现场观测.
同位素追踪技术 (δ15N-NO3和δ18O-NO3) 用于识别污染源.
贝叶斯模型用于量化不同NOx排放源的贡献.

主要成果:

年平均湿NO3-N沉积量下降了35%,从7.76公斤N ha-1 yr-1 (2014-2015) 降至5.03公斤N ha-1 yr-1 (2021-2022).
与2014-2015年相比,2021-2022年同位素值显示季节性变化和总体下降.
车辆废气对湿NO3-N沉积的贡献显著增加,在2021-2022年超过了煤炭燃烧排放.

结论:

中国的空气污染控制政策已经导致在减少湿NO3-N沉积方面取得了阶段性成就.
观察到氧化占主导地位的来源发生了转变,汽车废气成为一个更重要的贡献者.
未来的战略应优先考虑机动车排放控制,同时保持对燃煤发电厂的努力.

关键词:

对空气污染进行控制.具有双同位素的双同位素.NO (x) 的排放量.酸盐沉积堆积物中的酸盐.源的可追溯性源的可追溯性

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