基于空间自相关的浙江省城市PM_(2.5)时空分异特征

Characteristics of Spatial-temporal Differentiation of Urban PM_(2.5) in Zhejiang Province Based on Spatial Autocorrelation

空间自相关分析是确定某一变量在空间上是否相关、相关程度如何的常用的一种方法。为了寻求PM_(2.5)污染在季节和空间的分异特征,对浙江省69个城市站点2014年春夏两季的PM_(2.5)日均浓度数据进行空间自相关分析,结果表明,浙江省城市PM_(2.5)污染空间差异明显;PM_(2.5)污染程度从高到低依次为浙北、浙中、浙东、浙西南、舟山群岛。浙江省PM_(2.5)污染在春夏两季均呈现较明显的空间集聚特征,PM_(2.5)污染高值集聚区分布在浙北平原;PM_(2.5)污染春季城市集聚较夏季明显,且春季PM_(2.5)浓度分布显著高于夏季。

Spatial autocorrelation analysis is to determine whether a variable is related to the space, a commonly used method. In order to find the spatial-temporal differentiation of PM2.5 pollution in the season and space, this article analyzed the daily average concentration data of PM2.5 in 69 cities in spring and summer in 2014 from the perspective of spatial-temporal differentiation. Analysis results showed that the PM2.5 pollution space difference is obvious in Zhejiang Province, including the northern, middle, southern part of Zhejiang province and Zhoushan Islands from a descending order in terms of the pollution degree. In spring and summer, the PM2.5 pollution degree takes on an obvious feature of spatial agglomeration. Among them, pollution of high values mainly concentrate in the northern part of Zhejiang plains. It turned out that in spring, the spatial agglomeration is more obvious than that in summer; and the values are also higher in spring.