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Wanshan mercury(Hg)deposit,locates in the southwest of China,is the biggest mercury deposits in Asia.Due to the long period of mercury-bearing minerals retorting activities,million tons of mercury calcines was abandoned to the environment.It has been proven that the emission of mercury from mercury mine-waste calcines piles was the important source of atmospheric mercury in local environment.The aim of the present study is to remediate the mercury calcines by adding agricultural additives and covering Vetiver(Vetiveria zizanioides).In this study,mercury calcines,which were taken from Wanshan mercury mine,were treated with different additives and planted with Vetiver in the greenhouse.Eight treatments were designed: mercury calcines(control),mercury calcines + grass(T1),mercury calcines + 10%(v/v,the same as below)soil(T2),mercury calcines + 10%soil + grass(T3),mercury calcines + 10%soil + 20%sawdust(T4),mercury calcines + 10%soil + 20%sawdust + grass(T5),mercury calcines + 10%soil + 20%humus soil(T6),mercury calcines + 10%soil + 20%humus soil + grass(T7).The Vetiver were maintained for 4 months and then the element gaseous mercury emission flux between the mercury calcines and atmosphere was analyzed using dynamic flux chamber(DFC)method.The results showed that the mercury emission flux of non-treated calcines(control)was 1106.07±236.71 ng m-2 h-1(n=176),whereas,the calcines treated with additives or additives +grass have the dramatically lower mercury emission flux than non-treated control.The T1,T2,T3,T4,T5,T6 and T7 have the mercury emission flux of 416.70±117.73 ng m-2 h-1(n=176),55.54±24.49 ng m-2 h-1(n=154),24.47±10.75 ng m-2 h-1(n=155),35.77±6.61 ng m-2 h-1(n=172),23.30±4.23 ng m-2 h-1(n=174),42.44±10.92 ng m-2 h-1(n=152)and 24.91±6.33 ng m-2 h-1(n=151),respectively.It seems that either calcines received the additives or planted with Vetiver can effectively prevent the elemental gaseous mercury emission.Moreover,the calcines treated with both additives and grass has the lower mercury emission flux than that treated with additives but non-grassed covered,demonstrating that the growth of grass can retard the mercury emission from calcines.The results from the present study suggest that the addition of agricultural additives to the mercury calcines and then cover the grass may be an effective way to inhibit the mercury emission.