Abstract: The botanical composition, community structure, species diversity and soil nutrients of artificial and semi-artificial plant community were investigated under different vegetation collocation conditions in coal mine dumps of a typical steppe. The results showed that annuals and biennials dominated in exposed slopes under natural restoration, with simple species composition and low height of community. Plant species richness significantly increased in the artificial vegetation recovery area. There were 34 species belonging to 13 genera and 33 families observed in the four experimental sites of different vegetation collocations. The plant community was dominated by planted species, accompanied with Astragalus melilotoides, Corispermum mongolicum, Stipa krylovii, Pennisetum alopecuroide, Chenopodium aristatum, and Salsola collina after restoration on coal mine dump slope (4-5 a). Among the four different vegetation collocations, the community collocation of shrubs and herbs (Ⅱ) had the highest Shannon diversity index and Margalef richness index, and soil total nitrogen and organic matter contents. Our results indicated that artificial collocation of shrubs and herbs of Medicago sativa + Caragana korshinskii had better performance in ecological restoration of coal mine dump in typical steppe, which provided reference for the vegetation restoration of coal mining area in the steppe.

Key words: Contribution of fertilization, Geographic differentiation, Interaction