Application and Precision Analysis of Tree height Measurement with LiDAR

Light Detection And Ranging (LiDAR), is a system of laser detection and distance measurement installed on aircraft or satellites. Because of its high angular resolution, high range resolution and anti-jamming characters, the objects heights on the earth surface can be acquired precisely with LiDAR. In forestry application, LiDAR with spot size smaller than 1m can acquire thousands of laser points and has been applied to estimating the biomass parameters of trees. In this paper, the measuring method of tree heights, as one of the biomass parameters, with LiDAR especially for wooded areas is introduced. The relative tree heights comparative experiments at Changping district in Beijing are carried out to discuss the feasibility and the accuracy of tree height measurement with LiDAR based on the relative true value acquired by the total instrument. The main equipment, the measuring method and the experiments are detailed introduced.According to the experimental analysis, it is indicated that the overall accuracy meets the applicational requirement and the tree height measure method with LiDAR is feasible. But at the same time, there are gross errors and exceeding values exsiting in the measure results and the main reasons of them are lower density of point cloud and more aliased points. The research can provide reference for forestry biomass measurement.