Inversion of the fluorescence spectral information of vegetation chlorophyll based on the inverted Gaussian model

In this study, the principle, advantages, and disadvantages of the three representative chlorophyll fluorescence remote-sensing inversion algorithms standard Fraunhofer Line Discrimination(FLD), 3FLD, and improved FLD (iFLD) were compared and analyzed, and the inverted Gaussian model fluorescence inversion algorithm (IGM-FLD) was proposed. Vegetation canopy spectral data were simulated by the soil canopy observation, photochemistry, and energy flux (SCOPE) model. The analysis of the simulated and measured spectral data revealed that in contrast to the model parameters of sFLD, 3FLD, and iFLD, those of IGM-FLD have definite physical meanings. In addition, the apparent reflectance baseline of IGM-FLD was more reasonable than that of the other models. Given these properties, the fluorescence inversion accuracy of the IGM-FLD model was higher than that of the other three models. Moreover, it only required the construction of a reflectance baseline in the 680–800 nm spectral range and can simultaneously invert the fluorescence information of the O2-B and O2-A bands.