摘要
为构建根径-胸径回归模型推算内蒙古自治区赤峰市北部的赤峰杨Populus×xiaohei var.xiaozhuanica立木材积,研究于2024年选择郁闭度大于0.2的赤峰杨人工林,在不同龄组共32个小班中选取925株样本,根径范围为8~40 cm。测量样本根径(D_(0.05))和胸径(D_(1.3)),使用线性、对数函数、多项式函数、幂函数共4种数学模型对根径与胸径的相关关系进行拟合并检验。结果表明,根径-胸径多项式函数数学模型的离差平方和、相对误差平均值和相对误差绝对值的平均值最小,相关系数接近1,总相对误差位于[-5,5]区间,F≤F_(0.05),公式D_(1.3)=-4.4512+1.0754×D_(0.05)-0.0046×D_(0.05)^(2)可描述赤峰北部区域赤峰杨胸径与根径的回归关系。该模型可在涉及盗伐、滥伐案件,且现地只有伐根的条件下计算赤峰杨胸径,再根据一元材积表推算立木材积。
To develop a root diameter-DBH regression model for estimating the standing timber volume of Populus×xiaohei var.xiaozhuanica in northern Chifeng City,Inner Mongolia Autonomous Region,this study selected 925 sample trees of P.×xiaohei var.xiaozhuanica from 32 subcompartments across different age groups in 2024.These samples were collected from pure plantations with a canopy density greater than 0.2,with root diameters ranging from 8 to 40 cm.The root diameter(D_(0.05))and DBH(D_(1.3))of the samples were measured,and four mathematical models-linear function,logarithmic function,polynomial function,and power function-were used to fit the correlation between root diameter and DBH,followed by model verification.The results showed that among the selected models,the polynomial function model for root diameter-DBH had the smallest sum of squared deviations,average relative error,and average absolute relative error.Its correlation coefficient was close to 1,the total relative error fell within the range of[-5,5],and F≤F_(0.05).Therefore,this formula can describe the relationship between DBH and root diameter of P.×xiaohei var.xiaozhuanica in northern Chifeng.This model can be used to calculate the DBH of trees when only stumps are present in cases involving illegal logging or overlogging,and then the standing timber volume can be estimated using an univariate volume table.
作者
贾刚
李大瑞
刘自搏
孔翠霞
周志峰
JIA Gang;LI Darui;LIU Zibo;KONG Cuixia;ZHOU Zhifeng(Academy of Inventory and Planning,National Forestry and Grassland Administration,Beijing 100714,China)
出处
《林业与环境科学》
2025年第4期107-112,共6页
Forestry and Environmental Science
关键词
赤峰杨
根径
胸径
回归关系
Populus×xiaohei var.xiaozhuanica
root diameter
diameter at breast height
regression relationship
