北京市典型绿化灌木阻滞吸附PM_(2.5)能力研究

Ability of Typical Greenery Shrubs of Beijing to Adsorb and Arrest PM_(2.5)

选取北京市典型绿化灌木物种大叶黄杨、小叶黄杨、紫叶小檗、矮紫杉,结合气室模拟与实地观测的方法,综合测定不同树种对PM2.5的吸附能力.同时,收集2012年12月~2013年5月间北京市区PM2.5浓度值,分析了北京市冬春季PM2.5污染特征.结果表明,由气室实验得到的4种植物对PM2.5阻滞吸附能力排序为:紫叶小檗>小叶黄杨>矮紫衫>大叶黄杨,其原因主要为叶片特征差异所致;室外测量结果表明,4种物种吸附能力排序为:小叶黄杨>紫叶小檗>矮紫衫>大叶黄杨.气室模拟与室外实测结果均表明,小叶黄杨和紫叶小檗具有较强的阻滞吸附PM2.5的能力;气室模拟与室外观测实验中植物阻滞吸附PM2.5能力的大小略有差异,其原因应与植物结构相关.同时,通过分析北京市PM2.5浓度的季节性变化,发现北京市冬季的PM2.5浓度值尤为高,且常绿灌木植物仍能表现出较好的阻滞吸附PM2.5的能力.

Four typical types of green shrubs of Beijing( Euonymus japonicus,Buxus microphylla,Berberis thunbergii cv. atropurpurea,Taxus cuspidate cv. nana) were selected to study their capacities in adsorbing and arresting PM2. 5using both field observations and air chamber simulations. Concurrently,in order to analyze the pollution characteristics of Beijing in winter and spring,the PM2. 5concentrations of December 2012 to May 2013 were collected. Experimental results showed that: From the gas chamber experiments,the ability to adsorb and arrest PM2. 5was in the order of Berberis thunbergii cv. atropurpurea > Buxus microphylla > Taxus cuspidate cv.nana > Euonymus japonicus,mainly due to the differences in leaf characteristics; Outside measurement results showed that the ability to adsorb and arrest PM2. 5was ranked as Buxus microphylla > Berberis thunbergii cv. atropurpurea > Taxus cuspidate cv. nana > Euonymus japonicus. Chamber simulation and outdoor observation showed that Buxus microphylla and Berberis thunbergii cv. atropurpurea had strong ability to adsorb and arrest PM2. 5; Meanwhile,the slight differences between the chamber simulation and outdoor observation results might be related to plant structure. Compared to tree species,the planting condition of shrub species was loose,and it greened quickly; By analyzing the Beijing PM2. 5concentration values in winter and spring,it was found that the PM2. 5concentration was particularly high in the winter of Beijing,and evergreen shrubs maintained the ability to adsorb and arrest PM2. 5.