A Study Of The Pollution Characteristics And Source Apportionment Of PM₁₀、PM_2.5 And PAHs In Guiyang

Guiyang is an important provincial capital city in the western of China,located at the intermountain basin. Because of the breeze and the static windyclimate condition,it’s sensitive to the change of atmospheric pollutantconcentration. In the past thirty years,the economy developed rapidly inGuiyang, but the problem of air pollution has become more and more serious.This study selected10representative sampling sites in Guiyang according tothe function area of Guiyan,and took the inhalable particles in atmosphere（PM10)、atmospheric fine particles（PM2.5）and the polycyclic aromatichydrocarbons (PAHs) as subjects,took sample from spring to winter,finally itdiscussed the seasonal variation characteristics of PM2.5and its concentrationlevel in depth. Besides,the concentration level,seasonal change,distribution ofspatial and structure of America EPA’sixteen kinds of polycyclic aromatichydrocarbons in airborne particulates were discussed; The pollution sources ofatmospheric particulate PAHs were analyzed with the multivariate statisticalmethod, and provided scientific basis for the prevention and control of PAHspollution in atmospheric particulates.1、the concentration range of PM2.5is13~17μg m-3and the mean score is71μg m-3in guiyang; the obvious seasonal variation characteristics was appeared：winter＞spring＞autumn＞summer；due to the increasing of coal combustionin winter and the temperature inversion weather occurred frequently, thespread of pollutants becomes difficult, which causes high concentrations of the atmospheric particulate;While in summer,due to the high temperature, thickatmospheric boundary layer and poor atmospheric stability, the pollutants areeasily to be diffused,so the concentrations of atmospheric particles is low.2、The total concentration of PAHs (∑PAHs) in PM10ranges from6.30to165.78ng m-3,with its uniform annual values55.53ng m-3; the∑PAHs rangesfrom2.88to142.85ng m-3in PM2.5,and its uniform annual values41.16ng m-3;it appears obvious seasonal variation characteristics：winter＞spring＞autumn＞summer.3、The PAHs pollution in the business zone is the most heavily insummer,which is caused by the night barbecue in Hequn road;In winter,thepollution is severe in the residential areas of Nanxin yuan,Ruihua communityin Xiaohe and Jinyang Century City District,which can be reasoned by theresidential coal-fired and cooking.4、In17~27℃,the temperature and PAHs concentration showed a significantnegative correlation, and between-2~12℃, there was a a weak negativecorrelation between the temperature and the PAHs concentration.5、Through factor analysis and multiple stepwise regression analysis,thecontribution of the sources of16PAHs in Guiyang’s4seasonal PM2.5andpollution source rates are as follows:1) In spring, the major source of PAHs in PM2.5comes from motor vehicleexhaust gas, natural gas, coal, coke oven, and the contribution rates are48%,22%,19%,11%. 2) In summer, the major source of PAHs in PM2.5comes from motor vehicleexhaust gas and natural gas, coke oven, and the contribution rates are77%,23%.3) In autumn, the major source of PAHs in PM2.5comes from motor vehicleexhaust gas, coke oven,coal and natural gas, and the contribution rates are43%,37%,20%.4) In winter, the major source of PAHs in PM2.5comes from motor vehicleexhaust gas, natural gas, coal, coke oven,and the contribution rates are50%,22%,15%13%.