Fig. 4: Potential mechanisms of how warming enhances the priming effect.
From: Experimental warming accelerates positive soil priming in a temperate grassland ecosystem
a PLS model showing the relationships among soil temperature, soil properties, active bacterial community and priming effect. The active bacterial community composition (β-diversity) is represented by the PC1 to PC7 from the PCoA analysis based on Bray-Curtis dissimilarity metric. Directions for all arrows are from independent variable(s) to a dependent variable in the forward selected PLS models (p < 0.05 for both R2Y and Q2Y); only the most relevant variables (variable influence on projection > 1) are presented. Each number without parenthesis near the pathway is the PLS partial R2 (Eq. (2)) and the significance is based on permutational test (1000 times) of PLS R2Y. Each number in the parenthesis is the coefficient of determination (R2) between the two connected variables and the significance is based on Pearson correlation test or Mantel test (for β-diversity). The arrow width is proportional to the strength of the relationship determined by the PLS partial R2. Significance is indicated by *0.01 <p ≤ 0.05; **0.001 <p ≤ 0.01; and ***p ≤ 0.001. b Linear regression between Mineral N (NH4+ + NO3-) from the field and the primed C determined in laboratory (red: warming samples; blue: control samples). c Linear regression between plant biomass from the field and the primed C determined in laboratory (red: warming samples; blue: control samples). For (b and c), p values are calculated using a one-sided permutational test, constrained by treatment and block factors. Source data are provided as a Source Data file.
