Characteristic of pollution and sources apportionment of PM2.5 in NanChang city

Five sampling areas which represent traffic center, industrial area, commercial area, residential area and the suburb were set in NanChang city to collect PM_2.5 samples in summer and winter of 2007. The data at various sampling areas illustrated that the daily average concentration of PM_2.5 in summer were lower than that in winter. In different areas the pollution severity order of PM_2.5 was traffic roads (worse than), industrial zone, commercial mixing zone, residential zone and suburbs. Distinct space-time distribution characteristics of element average concentration were shown in different functional areas. The element average concentration of urban areas was higher than that of the suburbs, while the element average concentration of the traffic roads and industrial zone was higher than that of the commercial mixing zone and residential zone. The results of source apportionment illustrated that soil dust, burnt dust, building dust, vehicle dust and metallurgical dust were the dominant emission sources of PM_2.5 in atmospheric environment of Nanchang. Whether the concentrations of PM_2.5 reached the standard depends on soil dust, burnt dust and building dust, which become the emphasis of pollution control.