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Fig. 4 | Microbiome

Fig. 4

From: Protist communities are more sensitive to nitrogen fertilization than other microorganisms in diverse agricultural soils

Fig. 4

Structural equation model (SEM) illustrating the direct and indirect effects of nitrogen fertilizers (N and NS treatments) on soil physicochemical properties and alpha diversity (faith_pd index) of bacterial, fungal, and protist communities. Continuous and dashed arrows represent the significant and nonsignificant relationships, respectively. Adjacent number that are labeled in the same direction as the arrow represents path coefficients, and the width of the arrow is in proportion to the degree of path coefficients. Green and red arrows indicate positive and negative relationships, respectively. r2 values indicate the proportion of variance explained by each variable. Significance levels are denoted with *P < 0.05, **P < 0.01, ***P < 0.001. Standardized total effects (direct plus indirect effects) calculated by the SEM are displayed below the SEM. The low chi-square (χ2), nonsignificant probability level (P > 0.05), high goodness-of-fit index (GFI > 0.90), low Akaike information criteria (AIC), and low root-mean-square errors of approximation (RMSEA < 0.05) listed below the SEMs indicate that our data matches the hypothetical models

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