Fig. 3

Empirical relations between the power model parameters (R ₁ and k) and soil temperature (T) in three subtropical forest soils. R ₁ is the initial respiration, i.e., the starting value of R _h when t = 1; k is the power indicates the rate of R _h change. PE, SS, and CB  in panels a-c represent the P. elliottii plantation, S. superba plantation, and conifer and broadleaf mixed forest soils, respectively. Models of fitting for PE, R ₁ = 0.001 T + 0.230 (r ² = 0.71), k = 0.038 T + 0.148 (r ² = 0.94); for SS, R ₁ = 0.052 T−0.068 (r ² = 0.95), k = 0.046 T + 0.076 (r ² = 0.74); for CB, R ₁ = 0.064 T + 0.052 (r ² = 0.99), k = −0.0002 T² + 0.009 T + 0.208 (r ² = 0.89)