Impacts of Light Use Efficiency and fPAR Parameterization on Gross Primary Production Modeling

•We utilized different approaches to derive LUE and fPAR and examined their capabilities for carbon modeling.•Both crops, maize and soybean, and deciduous forest were selected to study.•fAPARchl showed closer seasonal dynamics with GPP than MODIS MOD15A2 fPAR.•Estimated GPP using fAPARchl was closer to flux tower based GPP.•Using a site-specific LUEmax value derived from an analytic approach can improve GPP estimates.