6种城市绿地空气PM2.5浓度变化规律的研究

Variation of air PM2.5 concentration in six urban greenlands

为合理安排树木的种植和配置结构,发挥绿色植物在改善城市生态环境方面的重要功能,研究6种城市绿地空气PM2.5浓度的日变化规律、月变化规律,分析不同类型绿地空气PM2.5浓度差异以及不同天气条件下PM2.5浓度。结果表明:PM2.5浓度日变化和月变化规律明显,不同季节有显著差异;6种城市绿地空气PM2.5浓度在同一季节内没有显著差异,从均值来看,春、秋、冬季有乔木的绿地内空气PM2.5浓度较低,夏季草坪内空气PM2.5浓度较低;阴天颗粒物的浓度比晴天高45%,雨后阴天颗粒物的浓度比雨后晴天高426%,降水对PM2.5的清除作用在雨后晴天发挥的较好。

In this paper,We researched the variation of PM2.5,the concentration difference in 6 types of urban greenlands and concentration change under different weather,aiming to reasonably design and plan urban trees,embodying their important roles in improving urban ecology environment.The results show as follows： there is remarkable daily and monthly variation of PM2.5 as well as significant seasonal difference.But there is no significant difference among different greenlands in the same season.The concentration of PM2.5 in greenlands with arbor trees is lower than that without arbor trees in spring,autumn and winter.The concentration of PM2.5 is less in herb than that of in any other greenlands in summer.The mean concentration of PM2.5 is 45% higher in cloudy days than that of in sunny days,and after raining,this number becomes 426%.So precipitation plays an important role on alleviating PM2.5 and this is significant in sunny days after raining.