Plateau zokor mound community vegetation structure and stability in the Qinghai alpine steppes

Eospalax baileyi is one of the most important rodents living underground in the Qinghai-Tibet Plateau. It accumulates a mound of soil on the grassland through excavation behavior, forming bare hills of different sizes with a mosaic distribution, which has some impact on the surrounding plant communities. In this study, the plant species composition and important values of biomass composition of functional groups, species diversity and community stability were quantitatively analyzed, and the convergence rule of plant community structure and stability characteristics under grazing and fencing was clarified. The results indicated that: 1) Number of plant species was very small on mounds in fenced and grazing plots, there have 17 and 11 species, respectively. Fencing was beneficial to the invasion and growth of plants on the mound. 2) The formation of the mound increased biomass (122.71 g·m^–2) and the proportion of hemicryptophytes (20.77%), and decreased the proportion of geophytes (22.50%) in the surrounding plant communities, which promoted the transformation from grassland/sedge community to grass community, but had no effect on plant species diversity of the grassland community. 3) Fencing decreased the stability, while grazing increased the stability of grassland communities around mound and non-mound areas. 4) The increase in plant biomass in the mound meadow could partly compensate for the loss of biomass in the nude mound, with 35.28% and 57.93% loss in biomass in the nude mound in fencing and grazing plots, respectively.