湖南省马尾松相对树高曲线模型研建

Study on relative tree height curve model of Pinus Massoniana in Hunan

基于湖南省主要树种模型研建项目中50块马尾松样地的每木胸径和树高实测数据,经数据预处理后,构建了马尾松固定参数相对树高曲线模型和可变参数相对树高曲线模型。基于构建的树高曲线模型,计算林木材积和样地蓄积,并以二元材积公式计算蓄积作为真值,将基于树高曲线模型计算的蓄积、二元材积公式计算蓄积和一元材积公式计算蓄积进行对比。结果表明:固定参数和可变参数相对树高曲线模型的决定系数分别为0.844和0.857,体现了较好的拟合精度;两种方法统计的总体蓄积相对误差均在5%以内,满足林业行业标准要求的允许误差范围;分径级组或分起源统计样地蓄积相对误差,相对树高曲线模型均较一元材积公式表现出更高的精度,能有效避免产生较大偏差。构建的马尾松相对树高曲线模型能应用于生产实践。

Based on the actual measurement data of DBH and tree height of trees in 50 Pinus massoniana sample plots from the project of model development for major tree species in Hunan Province,the constant-and variable-parameter relative tree height curve models of Pinus massoniana stands were developed after data pre-processing.Based on the tree height curve models,the volumes of each tree and sample plot were calculated,and the volume calculated by the two-variable volume equation was taken as the true value.The stock volumes calculated by the tree height curve models,the two-and one-variable volume equations were compared.The results showed that the determination coefficients of constant-and variable-parameter relative tree height curve models were 0.844 and 0.857 respectively,which showed good fitting accuracy.The relative errors of the total volume calculated by the two methods were both within 5%,which met the allowable error requirement in forestry ministerial standards.The relative errors of volume by diameter group or origin also showed that the relative tree height curve model had higher precision than one-variable volume equation and it could effectively avoid significant deviation for volume estimation.Therefore,the constructed relative tree height curve models of Pinus massoniana stands can be used in practice.