森林工程2026，Vol.42Issue(4)：728-737,10.DOI:10.7525/j.issn.1006-8023.2026.04.007
基于混合效应模型的兴安落叶松人工林单木冠幅模型构建
Crown Width Model for Individual Trees in Larix gmelinii Plantations Based on Mixed-effects Models
摘要
Abstract
Based on dendrometric measurements from 12 permanent sample plots in Shuangfeng Forest Farm,Hegang City,Heilongjiang Province,a crown projection area model for individual trees in Larix gmelinii plantations was devel-oped.The relationships between crown projection area and factors including DBH,height-to-diameter ratio,and crown length ratio were analyzed through correlation analysis.The optimal model was selected from six common linear and non-linear candidate crown-DBH models.Single-tree variables were incorporated into this base model,and plot-level random effects were added to construct a mixed-effects model for individual-tree crown projection area in Larix gmelinii planta-tions.The developed crown models were evaluated and validated.The results indicated that crown projection area showed positive correlations with DBH and crown length ratio but a negative correlation with height-to-diameter ratio.The optimal base model was a linear function with R2a of 0.515 6.After incorporating height-to-diameter ratio and crown length ratio,the generalized linear model achieved R2a of 0.597 8.Based on this model,the mixed-effects model includ-ing plot-level random effects further improved the fit,yielding R2a of 0.629 7.Model validation and evaluation confirmed that the mixed-effects model demonstrated superior predictive performance.The developed Larix gmelinii plantations mixed-effects crown projection area model-incorporating DBH,height-to-diameter ratio,crown length ratio,and plot-level random effects exhibits excellent goodness-of-fit and precise predictive capability.With broad applicability and sig-nificant biological interpretation,this model provides a theoretical foundation for accurately predicting crown dimensions in Larix gmelinii plantations across Northeast China.关键词
兴安落叶松/人工林/冠幅模型/线性混合效应模型Key words
Larix gmelinii/plantation/crown width model/linear mixed model分类
农业科技引用本文复制引用
孙宇,邰立彬,李洋,王亮,朱万才..基于混合效应模型的兴安落叶松人工林单木冠幅模型构建[J].森林工程,2026,42(4):728-737,10.基金项目
龙江森工科技项目(KJXMSQ2023-00015). （KJXMSQ2023-00015）
