Characteristics of Atmospheric PM_2.5 and PM₁₀ Regulated by Forest Vegetation in the Tieshanping Forest Park of Chongqing

From August 2014 to July 2015,taking road monitoring plot in the Tieshanping Forest Park in Chongqing as the contrast,characteristics of atmospheric PM_2.5 and PM₁₀ under the regulation of different tree species,forest stands and structural characteristics were monitored by the High Precision Hand Held PM_2.5 (CW-HAT200).The results showed that variations of atmospheric PM_2.5 and PM₁₀ in the park road and under canopies of seven tree species were larger.Compared with concentrations of atmospheric PM_2.5 and PM₁₀ in the park road,each monitored tree species had different degrees of ability to reduce atmospheric particulate matter,and Liquidambar formosana had a stronger ability to reduce atmospheric particulate matter,but the ability of Phyllostachys heterocycla was weaker.The concentration of atmospheric PM_2.5 and PM₁₀ under the regulation of different forest stands was in the order of conifer-broadleaf forest > broadleaved forest > coniferous forest.The concentrations of atmospheric PM_2.5 and PM₁₀ of different vertical structures from forest stands all were in the order of tree layer > tree and shrub layer > tree,shrub and herb layer.On the contrary,the ability to reduce atmospheric particle matter all was in the order of tree,shrub and herb layer > tree and shrub layer > tree layer.Therefore,forest stand with a complete spatial structure (tree,shrub and herb layer) would have a stronger ability to reduce atmospheric particulate matter.