Study of Foliage Abundance and Laser Incident Angles on Rice Plant Height Estimation using a short-range LiDAR measurement

Abstract

Plant height, one of the fundamental crop growth parameters, is usually collected by a direct measurement. The authors have developed a method for the estimation of rice plant height by using a short-range LiDAR measurement from above a paddy rice canopy. In this method, the estimated rice plant height is calculated based on the analysis of the vertical distribution of 3D point cloud data, therefore the estimation is affected by foliage abundance and laser incident angle conditions. Plants with similar height but different foliage abundance were observed using a short-range LiDAR from above a paddy rice canopy to examine the influence of the incident angles on rice plant height estimation. The results of the examination showed that the influence of the incident angle condition was similar in different foliage abundance until the maximum tiller number stage. In addition, the estimation of rice plant height was not affected by foliage abundance in a laser incident angle less than 8 degrees which is almost a vertical incident condition.