天津市中心城区PM_(2.5)时空分异及污染暴露度研究——以2019年为例

Spatial and Temporal Variation of PM_(2.5) and Pollution Exposure in Tianjin City Center∶Take 2019 for Example

PM_(2.5)是复合型大气污染物的首要污染物,识别污染物时空扩散规律是城市大气污染防控的重要理论基础。研究应用GIS及SPSS等分析方法,探讨精细尺度下2019年天津市中心城区PM_(2.5)的时空分布特征及其污染暴露度。结果表明:(1)在时间变化特征方面,PM_(2.5)浓度呈现“冬季最高、春秋季次之、夏季最低”的特征。1月份、2月份为典型污染月,日均污染浓度呈现周期性起伏变化规律,具有周末和节假日浓度高于工作日的“周末效应”;(2)在空间分布特征方面,典型污染月的PM_(2.5)空间分布特征呈现“北高南低,单峰单谷”的态势;(3)在相关性方面,影响PM_(2.5)浓度空间分布的相关因素呈现工业强主导、交通弱相关,不同尺度敏感度分异的特征。

PM_(2.5) is the primary compound air pollutant,and understanding the spatial and temporal diffusion of contaminants is an essential theoretical basis for urban air pollution prevention and control.In this study,GIS and SPSS were used to analyze the spatial and temporal distribution characteristics and pollution exposure of PM_(2.5) in downtown Tianjin in 2019 at a fine scale.The results showed that:(1)In terms of time variation characteristics,PM_(2.5) concentration in downtown Tianjin in 2019 was"highest in winter,followed by spring and autumn,and lowest in summer".January and February are typical pollution months.The average daily pollution concentration showed periodic fluctuation,with the"weekend effect"that the concentration on weekends and holidays was higher than on weekdays.(2)In terms of spatial distribution characteristics,the typical monthly PM_(2.5) pollution in in downtown Tianjin showed a trend of"high in the north and low in the south,single peak,and single valley".(3)In terms of correlation,the relevant factors affecting the spatial distribution of PM_(2.5) concentration are strongly dominated by industry,weakly correlated by traffic,and differentiated by sensitivity at different scales.