Fig. 6. Correlation of grazing exclusion and grassland type with plant、soil and fungal diversity. Fraction represents grazing exclusion and grazing; Grassland type represents temperate desert、temperate steppe and mountain meadow. (p), plant; (m), microorganism. Circle size and color represent the Pearson correlation coefficient.
3.5. Potential drivers of soil fungal community diversity
SEM analysis showed that total soil nitrogen and total soil phosphorus had a direct effect on fungal community diversity, while grazing exclusion, grassland type and soil organic carbon had an indirect effect on fungal community diversity. Fraction had a significant effect on fungal community diversity by directly affecting total soil phosphorus (P < 0.05) and grassland type had a significant effect on fungal community diversity by directly affecting soil organic carbon, which in turn affected total nitrogen and phosphorus (P< 0.05). These variables explained approximately 40% of the variation in fungal community diversity (Fig. 7a). In addition, combining direct and indirect effects revealed that soil total nitrogen was the most important predictor of change in fungal community diversity (Fig. 7b).