基于实际和模型树木的TreeQSM建模估计树木参数性能分析  

Performance Analysis of Tree Parameter Estimation Based on TreeQSM Modeling of Actual and Model Trees

作　　者：吴毓涵 汪沛[1] 李雅新 刘重男 李汉隆 任竞 Wu Yuhan;Wang Pei;Li Yaxin;Liu Zhongnan;Li Hanlong;Ren Jing(School of Science,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学理学院,北京100083

出　　处：《中国激光》2023年第22期157-166,共10页Chinese Journal of Lasers

基　　金：第三次新疆综合科学考察项目(2022xjkk1205);北京市自然科学基金(6232031)。

摘　　要：树木的量化模型对分析树木拓扑结构和生物量等信息非常重要。树木定量结构模型(TreeQSM)作为主流建模方法,被广泛使用,但在估计树高、胸径和体积的精度上缺少全面分析。实验中用地面激光雷达多扫描角分辨率多站点扫描2棵模型树和5棵真实杏树,通过TreeQSM建模单站和多站融合数据估计得到较精确的树高、胸径和体积参数,同时分析不同角度分辨率、不同站点数量对估计树高、胸径和体积的影响。实验结果表明:树高和胸径的平均估计精度均在90%以上;对树木体积而言,结构较为简单的模型树平均估计精度为92.00%,结构较为复杂的真实杏树平均估计精度71.32%。由实验数据可知,扫描角分辨率和融合站数对精度有一定的影响,且不同参数最优估计结果的配置存在差别,同时TreeQSM也会受到点云数据基础、数据完整性和噪声等多因素影响,特别是针对复杂分枝结构和体积进行建模时仍存在一定的偏差,所提模型的改进空间巨大。Objective Tree point clouds can be used to estimate tree structure information in a nondestructive manner,which is very useful for studying forest ecosystems.Modeling and analysis of tree structures are critical in the investigation of tree topologies and biomass.One popular tree modeling method is a priori hypothesis modeling,which uses tree branches as cylinders and point clouds as input to model the branches by the topological structure of the tree skeleton.Tree quantitative structure modeling(TreeQSM)is an a priori hypothesis modeling method that enhances the regularity of tree models to rapidly obtain tree structures and is currently a mainstream tree modeling method mostly used for tree model reconstruction,biomass estimation,and other aspects.This study analyzed the accuracy estimations of tree height,diameter at breast height(DBH),and volume using TreeQSM based on multi-precision and multisite scans of two artificial model trees and five real apricot trees.Methods To achieve a more effective evaluation of the TreeQSM method,experiments were conducted using both artificial model and real apricot trees.The model trees were constructed from smooth logs without bark or from rough logs with original bark.The real trees were in the leaf-off stage.The DBH,height,branch length,and diameter of each tree were manually measured,and the tree volume was calculated.A RIEGL VZ-400 scanner was used to collect multiscan tree point clouds.Single-and multi-scan tree point clouds with different scanning parameters were used to construct tree structure models using the TreeQSM algorithm.The tree models were then used to evaluate tree parameters such as tree height,DBH,and volume.The estimated and actual values were compared,and the absolute and relative errors were calculated and analyzed.Results and Discussions The estimation accuracies of the tree heights and DBHs of smooth trees reach 98.51% and 100%,with average accuracies of 96.19% and 98.06%,respectively,whereas those of bark trees reach 100%,with average accuracies of

关 键 词：遥感 地面激光雷达 定量结构模型 点云 树木重建 

分 类 号：TP751.1[自动化与计算机技术—检测技术与自动化装置]