Retrieval of forest canopy LAI directly from airborne full-waveform lidar data

Forest canopy LAI is an important variable to the modeling of energy over regional and global scales. This paper explored the method to retrieve LAI and FAVD directly from full-waveform LiDAR data. At first, he full-waveform LiDAR data, including emitting and return laser waves, were denoised and decomposed. Based on the interaction model between LiDAR and forest, and the parameters of Gaussian decomposition, the forest FAVD was then inverted. Besides, the missing LiDAR data caused by high density forest and LiDAR system restrictions was filled based on the existing LiDARdata and CHM. At last, LAI of the research area was retrieved from the inversed FAVD, and validated by the LAI field measurement (r = 0.73, RMSE = 0.67).