Abstract: A quantitative survey of plant species was carried at the northern dumping site in the Heidaigou open pit coal mine in August and September of 2012. A total of five revegetation types were selected for the plant species composition and diversity survey: tree, tree + shrub, tree + herbage (Gramineae), tree + herbage (Leguminosae) and abandoned farmland. The results showed that species abundance of the abandoned farmland was 181.00±12.52, being higher than that of the other re-vegetation types. Species richness of the abandoned farmland and tree + herbage (Leguminosae) (4.50±0.95 and 4.78±0.87, respectively) was higher than that of the other re-vegetation types. Species abundance and richness showed positive relationships with soil organic matter and total nitrogen content, but negative relationships with soil phosphorus content. Increasing soil organic matter and total nitrogen contents in shallow layer is an efficient way to promote plant diversity restoration at the dumping site. Also, we suggest that nitrogenfixing plants should be given a preference for re-vegetation.

Key words: physico-chemical properties, biomass, organic matter, improvement effect, iron tailing