Abstract:Zoigȇ alpine wetland meadow, located on the eastern edge of the Qinghai-Tibetan Plateau, is degrading under the impact of global climate change and the increasingly heavy burden of livestock in recent years, demonstrating four typical phases,i.e. swampy meadow, grassland meadow, degraded meadow and desertifying meadow in the process. From April 2009 to October 2010, seven investigations were conducted of soil macrofauna communities in the four phases for analysis of impacts of the degradation on soil macrofauna. Results show that differences existed between the phases in taxonomic composition and dominant groups of the soil macrofauna communities. Statistical analysis shows that the impacts of the degradation on richness, density and Shannon diversity index of the soil macrofauna communities were extremely significant (p<0.01 or p<0.05) in the last two phases. Principal Component Analysis (PCA) shows that in the phase of graded meadow, Polydesmida and Coleoptera larvae increased significantly (p<0.05), while in the phase of desertifying meadow the dominant groups decreased significantly in density (p<0.05) and some common and rare groups disappeared. Correlation analysis shows that richness, density and diversity of soil macrofauna communities were closely related to species and biomass of the plants and physical and chemical properties of the soils (p<0.01 or p<0.05), especially available phosphorus and readily available potassium, in the meadows. And soil macrofauna communities also responded to changes in season significantly in abundance and diversity, and the responses varied from phase to phase of the degradation process (p<0.01 or p<0.05). All the findings indicate that moderate degradation of alpine meadows may increase soil macrofauna community in diversity, whereas severe degradation (desertification) significantly reduces the diversity, and moreover, seasonal dynamics of soil macrofauna communities varies from phase to phase of the degradation process.