The maximum carboxylation rate (Vcmax) is a key parameter in determining the plant photosynthesis rate per unit leaf area. However, most terrestrial biosphere models currently treat Vcmax as constants changing only with plant functional types, leading to large uncertainties in modelled carbon fluxes. Vcmax is tightly linked with Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). Here we investigated the relationship between leaf chlorophyll content and Rubisco (Chl-Rub) within a winter wheat paddock. With chlorophyll as a proxy of Rubisco,...