基于广西森林资源年度监测评价项目中25块杉木样地和25块桉树样地的每木胸径和树高实测数据,从7个传统树高-胸径曲线中筛选出拟合精度最优模型作为基础模型,引入林分优势高和气候因子构建广义非线性模型,通过10折交叉验证法进行检验,并对一元材积公式的估计误差进行评价。结果显示:1)各传统树高-胸径曲线模型中,Richards模型为杉木和桉树最优的基础模型;2)引入了林分优势高和气候因子的杉木和桉树树高-胸径广义非线性模型,拟合精度相对基础模型更高,杉木的R²,MPE和MPSE的值分别为0.797 6,0.58%和13.91%,桉树的R²,MPE和MPSE值分别为0.720 7,0.62%和11.58%;3)采用一元材积公式得到的杉木和桉树总体蓄积与实测蓄积相差较大,其中桉树相对误差为-13.51%,超过了林业行业标准要求范围,运用树高-胸径广义非线性模型和二元材积公式计算总体蓄积,与实测值相对误差不超过0.5%,构建的杉木和桉树树高-胸径广义非线性模型能运用于实践生产。

Based on the mensuration data of diameter at breast height(DBH)and tree height from 25 Plots of Cunninghamia lanceolata and 25 plots of Eucalyptus robusta in the annual monitoring and evaluation of national forest resources of Guangxi Zhuang Autonomous Region,the basic model with the highest simulation accuracy was selected from seven common tree height-DBH curve models,then stand dominant height and climate data were introduced to build generalized nonlinear models.The 10-fold cross-validation method was applied to test the models,and the estimation error of one-dimensional volume formula was evaluated.The results showed that:1)Among the traditional tree height-DBH curve models,Chapman-Richards model was the basic model with the highest accuracy;2)Compared with the basic model,the generalized nonlinear tree height-DBH model with stand dominant height and climate data had higher fitting accuracy.The determination coefficient(R²),mean prediction errors(MPE)and mean percent standard errors(MPSE)of Cunninghamia lanceolata model were 0.7976,0.58% and 13.91%,respectively,and those of Eucalyptus robusta model were 0.7207,0.62% and 11.58%,respectively;3)The volume calculated by the one-dimensional volume formula was quite different from the measured volume,especially the Eucalyptus robusta reach -13.51%,which exceeded the scope of forestry industry standards.It was worth noting that the relative error calculated by the binary volume formula and the generalized nonlinear tree height-DBH model is not above 0.5%.The generalized nonlinear tree height-DBH model of Cunninghamia lanceolata and Eucalyptus robusta can be well applied to practical production.