Based on PROSAIL and four scale model to estimation LAI from HJ-1B CCD2 data in Zhangye

Leaf area index (LAI) is an important ecological and environmental parameter. Currently, most LAI inversion methods are based on single model. For continuous vegetation canopy, PROSAIL model used to retrieve vegetation biophysical properties based on lookup table or neural network methods. As for discontinuous vegetation canopy, vegetation canopy reflectance was simulated from Geometric-Optical model, and the relationship between LAI and vegetation indexes was established using simulated reflectance. This paper introduces a method combining the PROSAIL and four-scale model simulated the continuous and discontinuous vegetation canopy reflectance respectively, and then establishes lookup tables among multispectral reflectance, vegetation indices and LAI. The new method using land cover map has been employed to inverse HJ-1B CCD2 LAI in zhangye region of the middle reaches of the Heihe river basin. Results show that the new inversion results have much more deviation with observed dataset, but have good agreement with MODIS LAI in crops.