Fig. 3: Using CUE to improve the understanding of respiration components and processes across flux sites.
From: Global variation in vegetation carbon use efficiency inferred from eddy covariance observations
a, Partitioning ecosystem respiration (Reco) into autotrophic respiration (Ra) and heterotrophic respiration (Rh). The panel presents annual GPP, Ra and Rh normalized by Reco. The raw unit for carbon fluxes is g m−2 year−1. The number above each group of bars indicates the number of site-years for that PFTs. The error bars represent 1 s.d. of the variables, calculated from the values of all site-years within each PFT. b–d, The relationships between CUE and the key parameters for Ra, including the coefficient of growth respiration (gR; unitless) (b), the fraction of live biomass turned into non-respiratory biomass per unit time (τ; unitless) (c) and the temperature sensitivity of the maintenance respiration (Ea (eV)) (d). The shaded areas indicate 1 s.d. of the fitting by bootstrapping CUE, gR, τ and Ea 1,000 times according to their uncertainties.
