2012 Volume 24 Issue 1 Pages 21-25
Vertical plant area density profiles of rice canopy at different four growth stages were estimated using a high-resolution portable scanning lidar. 3D point cloud data on the canopies were collected by a portable scanning lidar with laser beams inclined at zenith angle of 30°. This laser beam zenith angle was selected to avoid obstruction of the beam into the lower canopy by the upper part. Based on the lidar-derived images, PAD values were computed in each growth stage by using the voxel-based canopy profiling method. The values were compared with ones directly measured by stratified clipping. The root mean square errors were 0.36 to 1.81 m2 m-3 at each growth stage and 1.20 m2 m-3 across all growth stages. Plant area index was also estimated, with absolute percentage errors of 4.0 to 20.6% at each growth stage and of 9.9% across all growth stages.
