Abstract:Soil nutrient deficiency and low bioactivity in historical quarries exists. In order to accelerate the ecological reconstruction of the quarry soil and provide suitable conditions for ecological restoration of damaged bare land, this study selected organic fertilizer and natural rice husk as the base fertilizer and Bacillus mucilaginosus (BM), Streptomyces microflavus (SM) and Trichoderma reesei (TR) as the soil ameliorating bacterial agents, and set T0(base fertilizer), T1 (base fertilizer+BM+SM), T2 (base fertilizer+BM+TR), T3 (base fertilizer+SM+TR) and T4 (base fertilizer+BM+SM+TR), indoor soil incubation tests were conducted with the original quarry soil as the control CK, 14 indicators such as pH, conductivity, organic matter, available nutrients, the enzyme activity and microbial quantity were measured, Soil Quality Index (SQI) was used to evaluate Soil quality in order to explore the improvement effect of different compound microbial agents on quarry Soil. (1) The soil acidity decreased and the electrical conductivity increased by 0.24-0.65 fold after the treatment of base fertilizer and compound microbial agent. The contents of organic matter, available nitrogen, available phosphorus and available potassium increased by 52.96%-82.48%, 761.67%-846.10%, 1211.81%-2115.67% and 69.73%-111.14% respectively. The total amount of soil microorganism was 1.99-36.87 fold higher than that of the control, and the soil enzyme activity significantly increased (p < 0.05); (2) The SQI was in the order of T4 > T2 > T3 > T1 > T0 > CK, The soil quality comprehensive index of T4 treatment was the highest (0.848) , and the soil improvement effect was the best. Base fertilizer and compound microbial agent can effectively balance soil acidification index, improve soil nutrient content and biological activity, improve soil quality, and provide guarantee for vegetation growth, which has obvious improvement advantages compared with single application of base fertilizer.