Photochemical reflectance ratio for tracking light use efficiency for sunlit leaves in two forest types

The estimation of maximum carboxylation rate (Vcmax)—a critical determinant of the terrestrial carbon simulation—over space remains a challenging task. Inverting the Vcmax through the sunlit gross primary productivity (GPP) is a possible solution if the key parameter sunlit light use efficiency (ɛsun) could be acquired through remote sensing approaches. Previous studies have shown that the reflectance centered at 531nm (R531) is very sensitive …