[Atmospheric deposition fluxes and seasonal variations of elements in northeast of Sichuan, central China].

Monthly atmospheric deposition was collected in Northeast of Sichuan Province from August 2011 to July 2012. Contents of Na,Mg,Ca,K,Si,Sr,Ba and Zn in weak-acid leachable fraction( with pH values of ca. 2) of the deposition were determined using ICP-MS. The results indicated that the deposition fluxes of all these elements exhibited notable seasonal variations. For example,the deposition flux of Na increased with precipitation,suggesting a dominant derivation from wet deposition; whereas the fluxes of Ca,Ba, Si,Sr and Mg displayed higher values during winter or spring season,suggesting that these elements may be closely associated with atmospheric dust activity. The annual fluxes of these elements were remarkably different in value. Na had the highest flux of 30 497 μg·( 102cm2·a)- 1,more than three orders of magnitude higher than the lowest flux of Ba of 27. 4 μg·( 102cm2·a)- 1.