摘要
基于2015—2022年成都市空气质量指数(air quality index,AQI)、大气污染物质量浓度的逐时数据,利用数理统计分析成都市空气质量及污染物质量浓度的时间变化特征,采用克里金插值法(Kriging)分析主要污染颗粒物PM_(2.5)和PM_(10)的空间分布特征,运用皮尔逊相关性分析探讨空气质量指数与污染物浓度之间的相关关系。结果表明:(1) 2015—2022年成都市空气质量以优良天气为主,AQI年均值为73,年际变化率为34%,呈逐年降低的趋势,AQI月变化波动幅度较大,月均值最大值出现在1月,为120,最小值出现在9月,为45。(2) PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、CO年平均质量浓度逐渐下降,月平均质量浓度均呈“U”形变化趋势,月均最大值出现在12月或次年1月,O_(3)年平均质量浓度逐年波动上升,月平均质量浓度变化趋势呈双峰结构,最大值出现在5月和7月。(3)成都市首要污染物以PM_(2.5)和PM_(10)为主,年累计出现次数分别为1 285 d和522 d,冬季出现频率较高,冬季出现天数分别为598 d和73 d,分别占出现天数的46.5%和14%。NO_(2)出现天数为689 d,夏秋季频率高。以SO_(2)和CO为首要污染物的超标天数均为0。(4) AQI大致呈现出中部高、四周低的空间分布特点,污染物浓度的分布具有明显的空间差异。PM_(2.5)和O_(3)空间分布特征为从东北向西南逐渐增加,PM_(10)、CO、NO_(2)从中部向四周逐渐扩大,SO_(2)从北向南逐渐减少,在中部出现高值中心。(5)大气颗粒物污染以PM_(2.5)为主,AQI与PM_(2.5)、PM_(10)、NO_(2)、SO_(2)、CO均呈显著正相关,与O_(3)呈负相关。PM_(2.5)、PM_(10)对AQI影响作用较大。
Based on the hourly data of Chengdu air quality index(AQI)and air pollutant mass concentration in 2015-2022,the tem-poral variation characteristics of air quality and pollutant mass concentration in Chengdu were analyzed by mathematical statistics,the spatial distribution characteristics of PM_(2.5) and PM_(10) of major pollutants were analyzed by Kriging interpolation,and the correla-tion between air quality index and pollutant concentration was explored by Pearson correlation analysis.The results showed that:(1)The air quality in Chengdu in 2015-2022 was mainly good,the annual average value of AQI was 73,the interannual change rate was 34%,showing a trend of decreasing year by year,the monthly fluctuation of AQI was significant,the maximum monthly aver-age value 120 appeared in January,and the minimum value 45 appeared in September.(2)The annual average mass concentration of PM_(2.5),PM_(10),SO_(2),NO_(2) and CO gradually decreased,the monthly average mass concentration showed a“U”shaped change trend,the monthly average maximum value appeared in December or January of the following year,the annual average mass concentration of O_(3) fluctuated and increased year by year,and the monthly average mass concentration showed a trend of bimodal structure.The maximum occured in May and July.(3)The primary pollutants in Chengdu were mainly PM_(2.5) and PM_(10),with a cumulative annual occurrence of 1285 days and 522 days,respectively.They had a higher frequency in winter,with the occurrence frequency of 1,598 days and 73 days,accounting for 46.5%and 14%of the occurrence days,respectively.NO_(2) occurred in 689 days,with a high frequency in summer and autumn.The number of days exceeding the standard with SO_(2) and CO as the primary pollutants was 0d.(4)AQI generally showed the spatial distribution characteristics of high in the middle and low in the surrounding area,and the dis-tribution of pollutant concentration had obvious spatial differences.The spatial distribution of PM_(2.5) and O_(3) was characterized by a g
作者
卢可欣
滕泽宇
LU Kexin;TENG Zeyu(Jilin Provincial Research Center for New Fertilizers,Jilin Normal University,Siping 136000,China)
出处
《三峡生态环境监测》
2024年第1期60-71,共12页
Ecology and Environmental Monitoring of Three Gorges
基金
吉林省科技发展计划项目(YDZJ202201ZYTS495)。
