Abstract:In order to clarify the treatment effect of Microbial Induced Calcium Carbonate Precipitation (MICP) in the heavy metal tailings in highly wind erosion areas in arid and semi-arid region, this paper used Bacillus (Lysinibacillus fusiformis) as the research object, which was the carbonate-mineralizing bacteria-spindle lysine bacillus screened in the habitat soil of the study area. We added the bacillus fermented liquid and the cementing solution mixed by 1mol/L urea and calcium chloride in the tailings slag to carry out indoor simulation experiments. And we compared the varieties of basic physical and chemical properties (heavy metal element content, pH, electrical conductivity and enzyme activity) in tailing slag with different size which were from slope top (fine particles:K1<5 mm), slope middle (middle particles:5 mm15 mm) before and after MICP treatment. And according to the method of two factor analysis of variance and correlation comparative analysis, we revealed the effect of MICP remediation technology based on habitat microorganisms on the regulation of regional tailing slag pollutants and determined the dosage of bacterial agent in MICP technology for the remediation of tailing slag with different particle sizes. The results showed that the MICP treatment had a significant effect on the basic physical and chemical properties such as heavy metal content, pH, electrical conductivity and enzyme activity in tailings slag. Under the MICP treatment, the arsenic (As) content of small particles (K1<5 mm) reduced by 21%, the mercury (Hg) of medium particles (5 mm15 mm) decreased by 22%. The pH in K1 and K3 reduced by 5% and K2 reduced by 4%. The total potassium (K) and urease in K1 significantly increased by 33% (p<0.05), the total carbon in K2 increased obviously by 39% (p<0.05), and the sucrase in K3 increased by 7% (p<0.05). The amount of microbial carbon and nitrogen significantly increased in K1, K2 and K3 (p<0.05). At the same time, Ni-Pb, As-Cu, electrical conductivity and Pb were significantly positively correlated (p<0.01) under MICPtreatment and pH-Pb was extremely significantly negatively correlated (p<0.01). And after MICP treatment, the correlations among total nitrogen, total potassium, total phosphorus, the contents of organic matter, heavy metal elements were enhanced.In summary, the MICP remediation technology based on habitat microorganisms could reduce the content of heavy metal elements amount in tailings slag, adjust the nutrient status of tailings slag soil, so as to regulate the quality of contaminated soil, and reduce the risk of environmental pollution caused by mineral resources development. At the same time, this study further determined the application dosage of bacterial agent for different particle tailings restoration to reach the remediation level, which has the better application value in the treatment and remediation of polluted soil.