城市公园不同活动空间PM2.5浓度的不均匀分布特征研究

Uneven Distribution of PM_(2.5) in Different Recreational Spaces of City Park

在轻中度污染天气下,选取公园内的露天广场、林荫道、亲水平台、滨水亭廊、紫藤花架、大草坪作为实验监测点,对6处活动空间内PM_(2.5)浓度的时空不均匀分布特征及其与主要环境因子的关系进行分析。研究结果表明,一天中不同时间段各空间的最大差别为1.77倍,林荫道和紫藤花架试验点的总体PM_(2.5)浓度均值低于其他活动空间;不同活动空间的PM_(2.5)浓度日均变化趋势不同,峰谷值出现时间点有差异;PM_(2.5)浓度值与温度和风速呈现负相关关系,在一定阈值范围内,与相对湿度呈现正相关关系。

In mild and moderate air pollutions,open plaza,avenue,waterfront platform,waterfront pavilion,wisteria pergola and great lawn were selected as monitoring points in the park.The experiment was conducted to synchronously observe uneven distribution of PM2.5 concentration and environmental impact factors in different spaces.Results show that the maximum difference between the six spaces is 1.77 times at different times of the day,the overall mean value of PM2.5 concentration in avenue and wisteria pergola is lower than that of other activity spaces;the daily variation trend of PM2.5 concentration in different activity spaces is different,and the appearance time of peak and valley value is variant;PM2.5 concentration exhibits a negative linear correlation with temperature and wind speed,showing a positive linear correlation with relative humidity within a certain threshold range.