Practical Application for Estimating the Crown Density of Conifers Using Lidar Data

The crown density is related with the hierarchical structure of the trees and one of the most important factors considering the biological diversity. This study focuses on the advantage of the LiDAR data, and we tried to estimate the crown density of conifers using the 3-dimensional distribution of the LiDAR pulses. The targets were selected from 13 areas of Hinoki and 10 areas of Cedar tree species in Izu region, Japan. The reference data was acquired by the interpretation of high-resolution optical airborne data inside 15m radius area. The gap rate was estimated by the ratio between 1st pulse reflected by the forest floor and others by plot area, and acquired crown density was compared with the reference one. The analyzed results showed that a highly positive correlation was found between them. In addition to the rate of crown density, a relative spacing was utilized, and the correlation coefficient affected the threshold of the forest floor. This study shows the potentiality of the LiDAR data for the estimation of the crown density of the conifers. The examination of the application to other tree species is necessary for the future studies. * Corresponding author.