武胜县2017-2019年PM_(10)与PM_(2.5)污染变化特征研究

运用统计学分析方法对武胜县2017-2019年环境空气自动监测数据PM_(10)和PM25的年度与季节间浓度差异及日变化趋势进行了分析。结果表明,近3年来,武胜县城区环境空气PM_(10)和PM_(2.5)的年均浓度以及PM_(2.5)/PM_(10)值总体均呈下降趋势,其中,PM_(10)的年均浓度虽总体呈下降趋势,但2019年出现反弹,PM_(2.5)的年均浓度和PM_(2.5)/PM_(10)年均值呈逐年下降趋势且降幅极其显著;PM_(10)和PM_(2.5)浓度月变化趋势均呈“V”字型,受秸秆焚烧的影响,4-5月和8-9月的PM_(10)与PM_(2.5)浓度出现反弹,4个季节间PM_(10)和PM_(2.5)浓度差异显著,冬季最高,春季次之,夏、秋季最低;PM_(10),PM_(2.5)和PM_(2.5)/PM_(10)值日变化曲线均呈“双峰双谷”型,PM_(10)和PM_(2.5)的峰值均出现在早晚交通高峰之后。武胜县需在建筑施工扬尘、道路扬尘、机动车尾气和生物质焚烧等方面加强管控。

The statistical analysis method was used to analyze the seasonal variations and diurnal curves of PM_(2.5) and PM_(10) concentrations in Wusheng County from 2017 to 2019 on the basis of the automatic monitoring data of ambient air.The results showed that the average annual concentrations of ambient air PM_(10),PM_(2.5)and PM_(2.5)/PM_(10) values decreased as a whole in the past three years.Although the average annual concentration of PM_(10) showed a decreasing trend,it rebounded in 2019.The average annual of PM_(2.5) concentration and PM_(2.5)/PM_(10) value showed a significantly decreasing trend year by year.The monthly variations of PM_(10) and PM_(2.5) appeared to vary in a V-shaped curve.Because of straw burning,the PM_(10) and PM_(2.5) rebounded from April to May and from August to September every year.The seasonal variations of PM_(10) and PM_(2.5) were significant,with the highest in winter,followed by spring,and the lowest in summer and autumn.The diurnal curves of PM_(10),PM_(2.5) and PM_(2.5)/PM_(10) values showed bimodal patterns,and the peaks of PM_(10) and PM_(2.5) concentrations all appeared after the morning and evening rush hours.In future,the construction dust,road dust,vehicle exhaust and biomass incineration,etc.needs to be strong controlled in Wusheng County.