Inserted panel d
shows the relationship between observed and modeled cumulative CO2 fluxes in mg C g−1 soil. Observed CO2 data is obtained from Rey et al. (2008) Hardwood site, soil layer of 10–
20 cm. A maximum likelihood estimate (MLE) was calculated for each of the well-constrained parameters (a–b),while a mean value was calculated for the poorly constrained parameter
(c).