Abstract: The use of ferrous mill tailings as reclamation substrate is an effective way for resource utilization. Based on potted culture method, we examined the impacts of hill-skill soil and straw addition on the properties of ferrous mill tailings substrate and the growth of Amorpha fruticosa seedlings. There were five addition levels of hillskill soil (0%, 25%, 50%, 75%, and 100%) and three addition levels of straw (1%, 3%, and 5%). The results showed that adding hill-skill soil reduced substrate bulk density, total and available P content, and increased field moisture holding capacity, cation exchange capacity, total and available K content. Adding straw reduced substrate bulk density and improved field moisture capacity, cation exchange capacity, totalorganic C, total N and P, available N and K content. The incorporation of hill-skill soil into ferrous mill tailings increased plant height, root length, ground diameter, crown width and biomass of A. fruticosa seedlings, while adding straw increased first and then decreased plant height, root length, ground diameter, crown width and biomass (3% addition > 1% and 5% addition). Comprehensive analysis indicated that A. fruticosa seedlings grew best in the treatment of 3% straw + 100% hill-skill soil.A. fruticosa seedlings grew well in the treatment of 3% straw + 50% hill-skill soil, with each index being significantly different from that of the treatment of 1% straw + 0% hill-skill soil (P<0.05). The application of 3% straw + 50% hillskill soil could be suitable as the formula for reclamation to realize the resource utilization of ferrous mill tailings.

Key words: light response model., Dendrocalamopsis oldhami, soil relative water content, photosynthetic physiological characteristics