Fig. 5: Microbial- ENzyme Decomposition (MEND) model calibration and simulation.
From: Experimental warming accelerates positive soil priming in a temperate grassland ecosystem
a–c Comparison of lab-MEND simulated and observed cumulative microbial respiration in the 7-day qSIP incubation experiment: (a) CO2 respired from the soil without straw addition, (b) CO2 respired from the soil with straw addition; (c) 13CO2 respired from the soil with straw addition; For (a–c), the error bar represents mean ± standard deviation (SD) (red: warming samples; blue: control samples). Observed CO2: mean of 4 biological replicates (n = 4); Simulated CO2: mean of 24 hourly simulation values (n = 24); MARE: mean absolute relative error (see Methods for details). d The field-MEND and TECO model parameter uncertainty assessed by the Coefficient of Variation (CV). The bars show the mean CV values of the 13 parameters for field-MEND and 10 parameters for TECO. The bars with different colors represent five model experiments and the above table columns of the same color list the information used in calibration process for each model. The + label indicates usage of the information when doing calibration. Blue: TECO model; Yellow: field MEND calibrated with Rh and microbial genes; Grey: field MEND calibrated with Rh, microbial genes and active fractions; Red: field MEND calibrated with Rh, microbial genes and Lab-MEND derived parameters; Light blue: field MEND calibrated with Rh, microbial genes, active fractions and Lab-MEND derived parameters. Lab-MEND derived parameters indicates replacing the parameter prior ranges with the parameter uncertainty ranges derived from lab-MEND calibration before calibration of field-MEND, which included five parameters (i.e., pEP, Vg, α, KD, and Yg). Significance is indicated by *0.01 <p ≤ 0.05; **0.001 <p ≤ 0.01; and ***p ≤ 0.001 with two-sided Wilcoxon tests. e, Comparison of the field-MEND simulated and observed field heterotrophic respiration (Rh) under control (blue) and warming (red). R2: coefficient of determination. No adjustments were made for multiple comparisons, and exact p-values are provided in the Source Data file. Source data are provided as a Source Data file.
