Abstract:Soil culture experiment was conducted with two kinds of mine tailing soils (wastelands and tailing residues land) planted two lespedeza species differing in Cd sensitivity in order to explore the remediation effects by adding xenobiotic substance (e.g., new soil, sawdust, organic fertilizer or inorganic fertilizer). The results showed that the biomass of Lespedeza bicolor was significantly higher than that of Lespedeza cuneata, while the treatment of applying new soil and organic inorganic fertilizer had the highest biomass of Lespedeza bicolor in all treatments. In addition, biomass of root and shoot were enhanced by xenobiotic application in both lespedezar species, which the addition of new soil improved the physical and chemical conditions of sites. When two mine tailing soils were applied with new soil or fertilizer, the heavy metal contents in roots or shoots of Lespedeza cuneata were significantly reduced, but little change occurred in Lespedeza bicolor. The contents of some heavy metals in two mine tailing soils can be reduced by applying exogenous or planting two lespedezal species, but the net uptake amount of heavy metals by plants are extremely low. In a word, the application of new soil and fertilizer obviously enhanced the site quality of two kinds of mine tailing soils, which increased the biomass of two Lespedeza species and decreased the uptake of heavy metals, so priority choose the tolerance plant species on the basis of soil amendment is the optimal way to improve the phytoremediation effect.