Abstract: A large number of bare mounds are formed by plateau zokor (Eospalax baileyi) interference in alpine meadows in the source region of the Yellow River. After the interference disappeared, the bare mounds naturally recover, which may alter the stability of grassland soil microbial community. The responses of soil characteristics and microbial community stability to the succession of bare mounds remain unclear. In this study, we analyzed the variations of soil properties and soil microbial community across three succession stages of zokor mounds in the source region of the Yellow River, including bare mounds (BM), short-term recovery mounds (SM) and long-term recovery mounds (LM), with healthy alpine meadow (YS) as the control. The results showed that soil moisture, soil water-holding capacity, soil bulk density, soil organic carbon and total nitrogen content gradually increased from bare mounds to long-term recovery mounds, with the growth rates being 26.48%, 1.90%, 36.14%, 15.87%, and 39.89% respectively. Soil conductivity gradually decreased, and soil β-glucosidase and alkaline phosphatase activities were higher in the recovery stage. Shannon diversity index, Pielou evenness index, resistance and resilience of soil bacteria and fungi as well as the niche breadth of soil bacteria increased with the recovering succession of bare mounds, Soil bacterial community stability had a strong correlation with soil physical properties (soil moisture, soil water-holding capacity, bulk density and conductivity) and organic carbon content, while soil fungal community stability had a strong correlation with soil β-glucosidase and alkaline phosphatase activities and organic carbon content. This study reveals the variations of soil microbial community stability during the recovering succession of plateau zokor bare mounds, which provides a theoretical basis for understanding the management and restoration strategy of alpine meadows in the source area of the Yellow River.

Key words: alpine meadow, Eospalax baileyi, soil microorganism, community characteristics, community stability