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A unique set of soil samples were collected to analyze the chemical composition and source characterization of Fugitive Dust over Xi'an city,namely,2 soil dust samples,19(4) paved road dust samples,53(17) construction dust samples and 2 cement production samples.By the means of high-sensitivity X-ray fluorescence and ion chromatography,the samples were detected contained eighteen elements like Na,Mg,Al,Si,K,Ca,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Ba and Pb and eight ions like Na+,Mg2+,Ca2+,F-,Cl-,NO3 - and SO4 2-,respectively.The most abundant elements in the samples were Al,Si,Ca and Fe.The elements of Ca,Zn,As and Pb had negative correlations to crustal elements (Si,Al,K and Ti) and were rich in Xi'an city,typically,which indicated that they were from non-crustal sources and can be used as the typical trace elements of construction dust emission.High correlations (r > 0.84; **P<0.01) were observed among crustal elements except Fe in dust samples which indicated that the source of Fe is different from others as it may come from oil burning.The observed Si/Al,K/Al,Ti/Al and Mn/Al ratios were similar to the source of Composite loess in Chinese Loess Plateau (CLP) and Upper Continental Crust (UCC): Furthermore,Fe/Al and Mg/Al were consistent with the Dust storm over NW China,implying that the fugitive dust were mixedly influenced by them.In cement samples,the ratios of K/Ca,Si/Ca and Fe/Ca were higher than other dust samples in Asian dust but much lower than in other urban cities,indicating there were significantly differences in the contributions of the energy structure of K,Si and Fe in Xi'an.Most of the water-soluble calcium had high correlation with evaluated carbonate (r=0.97),implying that Ca2+ is in the form of CaCO3 rather than other calcium minerals in Xi'an fugitive dust.The majority of K is insoluble (K+/K <20%),showing that the fugitive dust can be separated from biomass burning contributions.A similarity of major elemental potions and variation tendency in accordance with the characteristics of construction dust were observed in four types of fugitive dust (soil dust,cement,construction,paved road dust) over Xi'an area which shows that construction sites have great influences on the composition of city fugitive dust in Xi'an.