Fig. 5. Fungal community structure assessed by β-diversity
patterns using the principal coordinate analysis plots of Bray‒Curtis
distances. Different shapes represent grazing exclusion or grazing
soils, and colors represent grassland types. E,exclusion; G,grazing; TD,
temperate desert; TS, temperate steppe; MM, mountain meadow. ANOSIM
similarity analysis was used to test the significance between groups.
3.5 Correlations of grazing exclusion and grassland types with plant,
soil and fungal composition and diversity
In the 0-5 cm soil layer (Fig. a,c), all soil indices except the C:N
soil index were significantly correlated with the grazing exclusion
treatment, additionally, plant coverage was significantly correlated
with the no-grazing treatment, but fungal α-diversity was not
significantly correlated with the no-grazing treatment. Except for the
plant Pielou index and fungal Chao1 index, all other plant, soil and
fungal diversity indicators were significantly or highly significantly
correlated with grassland type. In addition, we found that soil SOC, KN,
TP, C:P, N:P and BD were significantly or highly significantly
negatively correlated with the fungal Shannon index and Simpson index.
In terms of fungal composition, Eurotiomycetes was significantly
and positively correlated with the plant Pielou index, KN, TP, N:P, and
pH, and Dothideomycetes was significantly and negatively
correlated with the SOC but significantly and positively correlated with
pH. We found that soil KN, TP and N:P were significantly or highly
significantly correlated with Dothideomycetes ,Archaeorhizomycetes , Agaricomycetes andGlomeromycetes .
In the 5-10 cm soil layer (Figs. b,d), plant cover was significantly
correlated with grazing closure treatments, and all plant, soil, and
fungal diversity indices, except for the plant Pielou index, fungal
Shannon index, fungal Chao1 index, and BD, were significantly or highly
significantly correlated with grassland type. In addition, we found that
soil C:N was significantly and positively correlated with the fungal
Shannon index and Simpson index, and soil C:P was significantly and
positively correlated with the fungal Chao1 index. In terms of fungal
composition, only Rhizophlyctidomycetes was significantly
negatively correlated with the plant Simpson’s index and highly
significantly negatively correlated with the plant Pielou’s index.