| A 3-year-term study on airborne particulate matter (APM) and air pollution trendin Fangshan District, Beijing has been undertaken supported by International AtomicEnergy Agency (IAEA) and National Natural Science Foundation of China. Samplingwas carried out using Gent SFU samplers at two stations, one is on the square in frontof the District Govornment Building, and another is in Liang Xiang middle schoolaffiliated to Beijing Normal University. A total of 272 samples was collected duringSep of 2005 and Oct of 2006. The samples collected are in two size fractions,PM10-2.5 (coarse) and PM2.5 (fine). More than 40 elements were detected for mostof samples by the Instrumental Neutron Activation Analysis (INAA) and hybridK0&relative software developed by our Lab. Elemental correlation analysis,Enrichment factor analysis (EF) and Positive matrix factorization (PMF) wereperformed for preliminarily investigations on the sources and trends of APM pollutionin this region.The PM10 was 138.4μg/m3 in 2006. It was less than 150μg/m3, which isprescribed in ambient air quality standard about the third criterion. Seven potentialsources of pollution were identified. The profiles for sources of soil, coal burning,timbering, fly ash, plant burning, industry smelt and incineration and their relativecontributions to the receptors (sampling sites) were deduced by PMF 1.1. Among the 7sources identified, soil and fly ash contribute 46.5% to receptor. Enrichment factor(EF) analyses were also performed to identify elements mainly from man-madepollution. The fine particles usually have larger EFs than coarse ones for pollutionelements; EF values of Al, Ce, Fe, Hf, La, Lu, Mg, Na, Sm, Th, Ti, V,Yb, Dy, Eu are close to one, indicating they are dust and soil origin. The preliminaryconclusions can be drawn from these analyses.
|
PDF Full Text Request