北京城区2007~2012年细颗粒物数浓度时空演化

为反映近年来北京城区细颗粒物数浓度时空演化过程,利用MODEL 3886GEO-α手持式激光粒子计数仪连续采集了2007~2012年北京城区93个采样点 6月上旬~7月上旬(非采暖期)和12月上旬~次年的1月上旬(采暖期)细粒径颗粒物PM (0.3、0.3~0.5、0.5~1.0) 的粒子数浓度数据,然后在地统计和空间分析方法的基础上,探究了北京城区细颗粒物数浓度的时空演化特征.结果表明,PM0.3在采暖期的数值均高于其在非采暖期的浓度值,而PM0.3~0.5和PM0.5~1.0在两个不同的采样期浓度值有高有低;采暖期不同下垫面细颗粒浓度差异较明显,而非采暖期下垫面类型对细颗粒浓度的影响相对较弱;非采暖期,北京城区南部的丰台区和东部的朝阳区细颗粒物污染最严重,市中心次之,而北部的海淀区和西部的石景山区污染相对较轻;采暖期,北京城区细颗粒物污染主要集中在朝阳区的东部和东南部,以及市中心及其周边区域.

Spatial-temporal evolution of fine particles concentration in Beijing City during 2007~2012

To reflect the spatial-temporal evolution of fine particles concentration in Beijing city in recent years, particulate matter of 0~0.3μm, 0.3~0.5μm and 0.5~1.0μm in heating period and non-heating period during 2007~2012 were measured using MODEL 3886GEO-α Handy Laser Particle Counter, then geo-statistical analysis about them was conducted. And spatial analytical method was used to study their distribution pattern. The results showed that value of PM0.3in heating period was greater than its concentration in non-heating period, while this law was not obvious for the values of PM0.3~0.5 and PM0.5~1.0 in these two different periods. In heating period, the concentration difference of fine particles on different underlyings was obvious, while underlying surface types had relatively weak impact on the concentration of fine particles in non-heating period. The highest concentration values of particulate during non-heating period existed in Fengtai District and Chaoyang District, which were respectively in the south and east of Beijing, followed by the city center. While the pollution in Shijingshan Dstrict in the west and Haidian District in the north was relatively lighter. In heating period, the air particulate pollution of Beijing city was mainly concentrated in the east and southeast of Chaoyang District, as well as the city center and its surrounding area.