The study on the characteristics of microbial biomass carbon and the evolution rules in reclaimed soil can be beneficial for the evolution monitoring of the reclaimed soil quality and can also provide a scientific basis for improving the reclaimed soil quality. In this work, the method of “spatial sequence instead of time series” was employed to study the changes of the microbial biomass carbon (MBC) and the soil basic breathing (SBR) with reclamation years of Dongtan coal mine in Zoucheng City, and the relationships of MBC and SBR to the soil environmental factors were also analyzed. The results suggest that: firstly, the MBC and qSMBC increased with reclamation years. Secondly, the SBR values of reclaimed soil were significantly higher than those of the control group, and the metabolic quotient (qCO2) tended to decrease with reclamation years. Besides, the soil microbial biomass content recovered gradually after reclamation, and meanwhile, the carbon utilization efficiency of the soil microbial biomass increased gradually, which indicated that the soil environment became more suitable for the microbe growth. Thirdly, the soil MBC showed an obvious proportional relationship (p＜0.01) to available nitrogen (AN), total nitrogen (TN) and soil organic carbon (SOC), indicating that soil nutrient deficiency is the main limiting factor to soil microorganism growth after reclamation. On the other hand, the qCO2 was inversely proportional to AN, AP and MBC (p＜0.01), but was proportional to pH (p＜0.05), implying that the lack of nitrogen and phosphorus and a high soil pH environment had a negative effect on the growth of microbe. In sum, those results are of great theoretical and practical significance for the comprehensive evolution monitoring of soil quality and for the guidance of the reclamation work in the future.

Key words：coalmining subsidence area; soil microbial biomass carbon; soil microbial quotient; soil basal respiration