【摘要】 基于四川省自贡市2014—2018年逐日平均国控站点空气质量监测数据,对自贡市PM2.5浓度时间和空间变化特征进行多尺度分析。结果表明,自贡市PM2.5浓度逐小时变化趋势主要与人类活动规律及太阳照射时间有关;逐日PM2.5的浓度达到国家空气质量标准天数比率为73.5%,其中一级标准的天数比率为27.5%;PM2.5浓度大值期主要在1、2和12月;且呈春秋冬季高、夏季低的分布特征,冬季超标天数占比高达69.02%;PM2.5浓度空间分布特征不仅受监测点位及地形、气候、城市结构等的影响,还与风向及周围其他城市污染源的贡献密切相关,整体表现为工业生产总值高、交通运输频繁、人口较为密集的大安区、高新区和贡井区PM2.5浓度水平较高。更多还原

【Abstract】 Based on the daily average air quality monitoring data of national control stations in Zigong area from 2014 to2018, the temporal and spatial variations of PM2.5 concentration in Zigong city were analyzed by using multi-scale data. The results showed that the hourly variation trend of PM2.5 concentration in Zigong area was mainly related to human activities and solar irradiation time; The ratio of days of PM2.5 concentration per day reaching the first-class national air quality standard was 27.5%, and the ratio of days reaching the second-class standard was 73.5%; The period of high PM2.5 concentration was mainly in January, February and December; And it had the distribution characteristics of high in spring, autumn, winter and low in summer, and the proportion of days exceeding the standard in winter was as high as 69.02%. The spatial distribution characteristics of PM2.5 concentration were not only affected by the location of monitoring sites, topography, climate and urban structure, but also closely related to the contribution of wind direction and other pollution sources in surrounding cities. Overall, PM2.5 concentration levels were higher in Da’an, Gaoxin and Gongjing district with high industrial output, frequent transportation and dense population.更多还原