标题：A comprehensive investigation of PM_2.5 in the Huaihe River Basin, China: Separating the contributions from meteorology and emission reductions

作者：Xiaoyong Liu, Jiqiang Niu, Zifa Wang, Xiaole Pan, Fangcheng Su, Dan Yao, Ming Zhu, Jun Yan, Junhui Yan, Gaowei Yao

来源出版物：Atmospheric Pollution Research, 2023年

DOI：10.1016/j.apr.2023.101647

出版年：2023

文献类型：Article

语种：英文

摘要：Due to anthropogenic emission reductions, the mass concentration of fine particulate matter (PM_2.5) in China has markedly decreased in recent years. In this study, we selected the Huaihe River Basin (HRB), which is located in the middle of the North–South climatic transition zone of China, to investigate the reasons for the decrease in the PM_2.5 concentration. Based on the observed PM_2.5 concentration and meteorological data for 2015–2020, the Kolmogorov–Zurbenko (KZ) filter method was employed to decompose the original time series of the PM_2.5 concentration. The results demonstrate that the short-term (PM_2.5ST), seasonal (PM_2.5SN), and long-term (PM_2.5LT) components of PM_2.5 variations over the HRB accounted for 55.6%, 34.7%, and 4.4% of the total variance, respectively. PM_2.5 variations in coastal cities and cities with relatively high latitudes and longitudes were more affected by the short-term component. It was identified that the PM_2.5 concentration in the HRB declined at a rate of 2.58-8.12 μg/m³/year. The meteorological conditions and emission reductions all positively influenced the PM_2.5 decrease, which contributed 30.09% and 69.91%, respectively, to the PM_2.5LT decrease in the HRB. It is noteworthy that with the PM_2.5 decrease, the conversion efficiency of SO₂ to sulfate and NO₂ to nitrate might be enhanced. The unbalanced emission reductions in SO₂ and NO₂ are not conducive to the further decline in PM_2.5. This study suggests that more efforts should be made to control NO₂ emissions in the HRB.

关键词：PM_2.5; KZ filter; meteorology; emission; Huaihe River Basin

影响因子：4.83

论文连接：https://doi.org/10.1016/j.apr.2023.101647