基于传感器技术的渭南市道路环境颗粒物污染特征及影响因素研究

Pollution Characteristics and Its Impact Factors of Particulate Matter in Street Canyon of Weinan Based on PM Sensor

为深入了解渭南市街区道路环境颗粒物污染时空分布特征,利用车载颗粒物传感器于2019年3月1日—5月31日对渭南市道路环境空气中PM_(2.5)和PM_(10)浓度开展在线走航测量,分析了影响渭南市道路环境颗粒物污染时空分布的主要因素.研究表明:①渭南市区内所有道路PM_(2.5)平均浓度范围为37.7~51.9μg/m^(3),浓度较高路段位于高新区东部和主城区;PM_(2.5)~10(粗颗粒物)平均浓度范围为65.8~119.1μg/m^(3),浓度较高路段位于各功能区城郊.②工作日早高峰时段(07:00—09:00)主城区道路环境PM_(2.5)、PM_(2.5)~10污染较非工作日严重,3种类型道路工作日07:00 PM_(2.5)~10平均浓度呈支路(103.5μg/m^(3))>主干道(102.1μg/m^(3))>次干道(96.9μg/m^(3))的特征.③对于高新区和老城区路段,除早晚高峰时段出现PM_(2.5)和PM_(2.5)~10浓度峰值外,凌晨时段渣土车行驶路段、裸地或施工现场周边路段易出现PM_(2.5)~10浓度峰值,其PM_(2.5)~10平均浓度最高达230.9μg/m^(3)(乐天大街西段的路段Ⅳ).研究显示,工作日早晚高峰时段,特别是早高峰,机动车排放导致渭南市高新区东部和主城区路段的PM_(2.5)污染加重,夜间渣土车行驶导致高新区和老城区靠近城郊路段的颗粒物(PM_(2.5)和PM_(2.5)~10)污染加重.

The temporal and spatial distribution of particulate pollution in Weinan street canyons was measured by vehicular particulate matter sensor from March 1 st to May 31 st,2019.The results showed that:(1)The concentration of PM_(2.5) varied from 37.7μg/m^(3) to 51.9μg/m^(3),and the sections with high PM_(2.5) concentrations were located in the east of the high-tech zone and the main urban area.The concentration of PM_(2.5-10) varied from 65.8μg/m^(3) to 119.1μg/m^(3) and the sections with high PM_(2.5-10) concentrations were located in the suburbs of each functional area.(2)The PM_(2.5) and PM_(2.5-10) of the road environment in the main urban area were more serious during the morning peak hours(07:00-09:00)of working days than on non-working days.In the main urban area,the order of PM_(2.5-10) concentrations among different types of road at 07:00 on working days was branch roads(103.5μg/m^(3))>main roads(102.1μg/m^(3))>secondary roads(96.9μg/m^(3)).(3)For road sections in the high-tech zones and the old urban areas,in addition to the peaks of PM_(2.5) and PM_(2.5-10) concentrations during the morning and evening peak hours,the peak of PM_(2.5-10) concentrations was likely to occur in the early morning hours on the road sections where construction trucks were driving,bare land,or sections surrounding the construction sites,and the highest concentration of PM_(2.5-10) was 230.9μg/m^(3)(west section of Letian Street:road sectionⅣ).The research showed that during the morning and evening peak hours of working days,especially during the morning peak hours,the traffic emissions had increased PM_(2.5) pollution of road sections located in the east of the high-tech zone and the main urban area.Road sections near the suburbs of the high-tech zone and the old urban area had aggravated the PM_(2.5) and PM_(2.5-10) pollution caused by the construction trucks at night.