Abstract:Vegetation cover plays a major role in the restoration and stabilization of disturbed systems.Comparative plant successional studies on dump,using a space-for-time substitution in the short-term,are providing significant insights into vegetation dynamics to ensure the success of future revegetation projects in these areas.Waste dump at Yimin opencast coalmine,Hulun Beier,was surveyed for naturally occurring plant species.The vegetation compositions,importance value and plant species diversity were compared.Altogether 64 naturallyr R.occurring plant species,belong to 21families,were observed in different waste dumps of Yimin opencast coalmine.The main families wereCompositae(14 species),Gramineae(12 species),Leguminosae(6 species)andChenopodiacea(5 species),which accounted for 57.8%of total species.According to the important value of species calculated,it is determined thatTribulus terrestrisandSalsola collinaacted as pioneer species on waste dumps,andStipa grandis,Leymus chinensis,Artemisia sacrorumandArtemisia halodendron were important dominant species in vegetation restoration in Yimin opencast coalmine.The overall species diversity of plant communities shows that the longer the natural recovery years last,the lower Alatalo(Ea)index become,and there is a significantly negative correlation between the Alatalo(Ea)index and the number of recovery years.Margalef(Ma)and Patriek(Pa) richness indices showed a increase trend,Shannon-Wienerd(H′)and Simpson(D)diversity indices showed a similar growing trend.The composition of species was becoming increasingly similar to the native plant community,and the species diversity index of each recovered plant community was higher than that of the native plant community,which shows that these communities need more time to reach steady states.