ABSTRACT

Rapid industrialization and economic take-off in coastal cities of China have placed great strain on the environment. In the this study, 40 aerosol samples were collected in the coast of Xiamen, Fujian province, west Taiwan Strait, P. R. China, from January to December 2003. The samples were analysed for the concentrations of elements (K, Ca, Na, Zn, Pb, W, Se, As, Ni, Ba, Nb, Ta, Zr, Hf, Th, U, Sr, REEs, etc.). All the elements display significant seasonal variations. The concentrations of most of the elements (except Na and Se) were high in January and February, abruptly decreased in March, kept relatively constant but low from April to August, and then gradually increased from September to December. This corresponds to the rainless climate and the influence of biomass burning from Southeast Asia in the winter and rain scavenging and the diffusion of typhoon in the summer. Thus, most of the elements have a good negative correlation with the monthly precipitation. The SEM/EDX studies indicate that the aerosols of Xiamen mainly consisted of soot grains, clay minerals, feldspar, gypsum, quartz, and biological particulates. The calculated enrichment factors indicate that Na and Br are derived from ocean, Pb, Zn, As, Sb, Se, W, and Ni are anthropogenic elements mainly derived from coal combustion, vehicle exhaust, and mining, and the other elements (i.e., Zr, Fe, Cr, Co, Rb, Sr, Cs, Ba, Hf, Ta, Th, U, and REEs) are crustal elements derived from weathered rocks and soil dust. The elemental concentrations of aerosols in Xiamen were compared with other cities, and the results indicate that Xiamen, like other coastal cities such as Qingdao, Dalian, Hong Kong, and Tokyo, has much lower concentrations of the elements such as Pb, Zn, and Cr than Beijing. The elemental deposition fluxes in Xiamen were also compared to other cities. The comparisons indicate that the elemental deposition fluxes in these cities are influenced not only by climatic characteristics (e.g., the precipitation and the sandstorm), but also by the industrial facility denseness.