东北林业大学学报2026，Vol.54Issue(10)：63-71,9.
竞争与优势木平均高主导驱动闽西北杉木幼龄林单木生物量
Competition and Dominant Height as Primary Drivers of Individual-Tree Biomass in Young Cunninghamia lan-ceolata Plantations,Northwestern Fujian
摘要
Abstract
To reveal the intrinsic driving mechanism by which slope position affects individual-tree biomass of Cunninghamia lanceolata,an 8-year-old C.lanceolata plantation was selected as the research material to analyze the effects of slope posi-tion on tree phenotypic traits,spatial structure,competition intensity and biomass.Under nearly identical slope aspect and gradient,three slope position treatments(upper slope,middle slope and lower slope)were established.A full tree inven-tory was implemented in permanent plots,and tree biomass was estimated using allometric growth equations.Stepwise re-gression and piecewise structural equation model were adopted to quantify the effects of various variables on biomass of the C.lanceolata plantation.The results showed that:(1)Slope position exerted significant effects on phenotypic traits inclu-ding diameter at breast height,height to crown base and crown radius(P<0.05).It further altered neighborhood competi-tion intensity and stand spatial structure,thereby regulating tree growth and biomass allocation patterns of C.lanceolata.Individual-tree biomass was the highest at lower slope positions,whose biomass allocation across different organs differed markedly from that on upper and middle slopes.(2)The coefficient of determination,root mean square error and mean absolute error of the stepwise regression model were 0.853,6.554 kg and 4.882 kg,respectively.The screened explana-tory variables contained crown radius(CR),competition index CI8,diameter differentiation index(T_Udm)and domi-nant height(Hdom).(3)In the piecewise structural equation model,the absolute values of path coefficients of all varia-bles on individual-tree biomass ranked in descending order:CI8(-0.945),Hdom(0.456),CR(0.055),T_Udm(-0.029).CI8 and dominant height were the primary driving factors of individual-tree biomass.(4)In subsequent forest management,rational thinning can be carried out to mitigate neighborhood competition pressure,combined with soil fertili-ty improvement measures,so as to effectively boost the growth and development of young C.lanceolata plantations.关键词
森林经营/杉木/生物量/坡位/结构方程模型Key words
Forest management/Cunninghamia lanceolata/Biomass/Slope position/Structural equation model分类
农业科技引用本文复制引用
潘占冬,王程,罗佳瑶,孙玉军..竞争与优势木平均高主导驱动闽西北杉木幼龄林单木生物量[J].东北林业大学学报,2026,54(10):63-71,9.基金项目
国家自然科学基金项目(31870620) （31870620）
林业科学技术推广项目([2019]06). （[2019]06）
