Heterogeneity of land cover data with discrete classes obscured remotely-sensed detection of sensitivity of forest photosynthesis to climate

•The climatic sensitivities of SIF were detected across the coarse forest pixels.•The heterogeneity was indicated by tree coverage (Tc) and landscape diversity (SHDI).•Overall, the climatic sensitivities of SIF were amplified with an increase in Tc.•The sensitivities also varied with SHDI, generally showing a negative correlation.