Volume 14, No. 7, December 2014, Pages 1986-1997 PDF(378 KB)
Hourly Variations and Potential Sources of Airborne Trace Elements in PM10 in Four Representative Regions of Southeastern China
Huajun Ye1,2, Kai Yang3, Xuejiao Jiang2, Lili Niu4, Daozhu Hua2, Dan Li2, Shuihe Shi5
1 State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China
2 Focused Photonics (Hangzhou), Inc., Hangzhou 310052, China
3 China National Environmental Monitoring Center, Beijing 100000, China
4 College of Environmental & Resource Sciences of Zhejiang University, Hangzhou 310058, China
5 Environmental Monitoring Station of Dongming County, Heze 274500, China
- The concentrations of trace elements in PM10 in four regions of southeastern China.
- The hourly variations and the sources of airborne trace elements.
- The correlations between PM10 concentrations and trace element concentrations.
Aerosol pollution episodes have frequently occurred in China in recent years, and the airborne trace elements in particulate matter have been a cause for concern worldwide because of their impacts on human health. However, there is limited information on the hourly variations of airborne trace elements. This paper describes a detailed investigation conducted in March 2013 on the hourly variations and potential sources of airborne trace elements. Trace elements in particles with aerodynamic diameters less than 10 µm (PM10) were monitored on-line in four representative regions with similar latitudes in southeastern China. Our results showed that the number of species of elements in PM10 detected at urban sites and an industrial park was greater than that at a rural site, due to the influences of human activities. The hourly variation patterns of trace elements indicated that their concentrations were stable during the day at the rural site, whereas a visible “double peak” of Pb and Cu was observed in the tourist city and a “single morning peak” of Pb and As was seen in the industrial city. These variations indicated the abundant traffic in the tourist city, and strong industrial emissions in the industrial city. However, the single morning peak and the slight double peak patterns of the trace elements were both found at the industrial park, indicating a combined source of industry and traffic. The results from the source identification also indicated that the sources of airborne elements were mainly industrial emissions at industrial sites, whereas the elements in the tourist city might primarily result from traffic. The correlations between PM10 concentrations and trace element concentrations were also studied. The results revealed that PM10 correlated better with elements originating from natural sources (e.g., K, Ca, Fe) than with those from anthropogenic sources (e.g., Pb, Zn, Cu). Our results provide a scientific basis for pollution control strategies at these sites.
Trace elements; PM10; Hourly variation; Potential sources.