2015~2022年南宁市环境空气质量变化趋势分析

Analysis of the Trend of Environmental Air Quality in Nanning from 2015 to 2022

为科学评价南宁市环境空气质量改善成效,提供大气污染防治攻坚决策支撑,本文利用环境空气质量日监测数据,采用Spearman秩相关系数法、KZ滤波法和ArcGIS空间分析等方法分析了南宁市2015~2022年环境空气质量变化趋势和污染特征。结果表明,南宁市近8年来除O_(3)浓度呈显著上升趋势外,其他大部分指标呈显著下降趋势,按综合指数评价,南宁市环境空气质量总体呈改善趋势;南宁市污染天首要污染物以PM_(2.5)和O_(3)为主,PM_(2.5)超标天数呈大幅度的下降趋势,而臭氧超标天数则呈波动性的上升趋势,臭氧已成为影响南宁市环境空气质量的主要污染物;冬季(12月至次年2月份)为南宁市PM_(2.5)污染防治攻坚的关键时段,重点管控秸秆焚烧源;8~10月份是南宁市臭氧污染的高发时段,重点管控区域是横州市和宾阳县。

In order to scientifically evaluate the improvement effect of Nanning's air quality and provide decision-making support for air pollution prevention and control,the Spearman rank correlation coefficient method,KZ filtering method,ArcGIS spatial analysis and other methods were used to analyze the change trend and pollution characteristics of Nanning's air quality from 2015 to 2022 which was based on the daily monitoring datas of air quality.The results show that in the past 8 years,except for the significant increase in O_(3)concentration,most other indicators in Nanning have shown a significant downward trend.Evaluated by the composite index,ambient air quality in Nanning City showed an overall improving trend.The main pollutants in Nanning City are PM_(2.5)and O_(3),with a significant decrease in the number of days PM_(2.5)exceeds the standard,while the number of days ozone exceeds the standard shows a fluctuating upward trend.Ozone has become the main pollutant affecting the environmental air quality in Nanning City;the key period for the prevention and control of PM_(2.5)pollution in Nanning City is winter(December to February of the following year),with a focus on controlling straw incineration sources;August to October was the high Ozone pollution periods in Nanning City,with key control areas being Hengzhou City and Binyang County.