In alpine meadows， the surface soil heaves to form hummocks under the influence of frost heaving， transforming the originally relatively homogeneous habitat into a heterogeneous one. In this study， 9 sampling plots were established along a soil moisture gradient in the alpine meadows of the Western Sichuan Plateau. We compared and analyzed the differences in plant communities and species diversity between hummocks and inter-hummock meadows under different soil moisture conditions. The results showed that： Soil physical properties and soil chemical properties exerted effects on the plant diversity of hummocks and inter-hummock meadows， respectively. The plant community on hummocks gradually transitioned from Kobresia （sedge）-dominated vegetation to shrub-dominated vegetation， while the plant community in inter-hummock meadows gradually shifted from Carex （sedge） and Kobresia-dominated vegetation to grass-dominated vegetation. The abundance of weedy plants and occasional species in hummocks was significantly higher than that in inter-hummock meadows. Habitat aridification increased the dissimilarity in species composition between hummocks and inter-hummock meadows， and the dissimilarity in species composition of hummocks was higher under different soil moisture conditions. In conclusion， hummocks tend to aridify the microhabitat and provide favorable conditions for the invasion of occasional species. Although hummocks increase plant diversity， they have a negative impact on the stability of alpine meadow vegetation. This research holds significant implications for guiding the conservation and management of alpine meadow vegetation.

Alpine meadow  /  Spatial differentiation  /  Species diversity  /  Grass hummocks  /  Inter-hummock meadows