| Atmospheric aerosol has important impact on many geophysical and geochemical processes, and affects the biosphere and geosphere significantly. With the rapid expanding of industry and economy, the magnitude of anthropogenic aerosol is explosively increasing. It's of great scientific and societal importance to study dry deposition of aerosol and the impacts to marine environment of aerosol particles and trace metals loaded on them.About 100 TSP and 30 PM10 aerosol samples were collected at ten days intervals for one year, from April 2001 to May 2002 at three sites, Yangkou, Baguanshan and Cangkou in Qingdao coastal region. As the basics and reference of morphological study, the concentrations of aluminium(Al), iron(Fe), manganese(Mn), copper(Cu), lead(Pb) and zinc(Zn) of each sample were measured using ICP-AES. The EXAFS analysis was used for the first time in the nation to examine the existing form of Fe in aerosol particles. The composition of metal on particle surface was studied by means of XPS. The morphological observation and composition analysis for bulk and individual particles were performed by using SEM/EDX for TSP and PM10 samples of four seasons and dust weather. Based on literature results, Slinn and Williams dry deposition models were improved reasonably, and the parameterization procedure had been developed for Qingdao area. The procedure calculates particle dry deposition velocity as a function of particle size and relative humidity as well as relevant meteorological variables. The dry deposition fluxes of six metals to Qingdao coastal waters were estimated using dry deposition velocities obtained from the above parameterizations.The concentrations of TSP at three sites and PM10 at Baguanshan site in Qingdao area were observed and measured by means of ICP-AES for one year. The results indicated that the concentrations of TSP and each metal decreased in the order of Cangkou>Baguanshan>Yangkou. While the concentration of each metal in PM10 islower than those in TSP collected in phase, the distribution ratios of Cu, Pb and Zn in PM10 are higher than those in TSP, indicating an enrichment of those anthropogenic metals in PM10 fraction. TSP and PM10 mass concentrations as well as crustal metals loaded in aerosol particles collected at three sites showed obvious seasonal variation, decreasing in the order of spring>winter>autumn>summer, but the concentrations of anthropogenic metals showed more complicated seasonal variability. It is also shown that a dust-storm preferably increases the contents of crustal metals and has less impact on anthropogenic ones.EXAFS analysis of Fe K-edge showed that an iron ion in aerosol particles is surrounded on average by 6 (coordinated) O ions. For the six samples examined, the coordination number of the first Fe-O coordination subshell is always 3 with a coordination distance (with O) in the range of 1.952-1.966±0.002 A, while the coordination number of the second subshell varies from 2.2 to 3.0 with a coordination distance of 2.108±0.002 A. The coordination is approximately consistent with that of a-Fe2O3, suggesting that iron in aerosol samples mainly presents in the form of a-Fe2O3. The fact that the coordination number in the second subshell is smaller than that of a-Fe2O3 might be an indication that there is a small amount of FeO mixed with a-Fe2O3 in aerosol particles. Existence of FeO was confirmed by a later XRD experiment.The metal composition and iron species on particle surface were studied by XPS for aerosol samples collected during dust and non-dust periods. The experiment results showed that Al and Cd exist in the form of Al2O3 and CdO in aerosol particles. The species of Pb corresponds to PbSO4, and Zn mainly present as ZnCO3 or ZnO. Sulfate is the main species of sulfur in particles. The curve fittings of Fe 2p peaks showed that iron mainly exists in forms of oxide, sulfate, silicate and phosphate, with some compounds adhering to SiO2 and/or Al2O3 particles. Iron in particles presents not only in trivalent compounds but also in bival...
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