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准确描述热带珍贵树种的林木干形变化,可为预估各材种数量、蓄积量及合理造材提供支撑。以热带格木、红锥和柚木3个珍贵树种,共120株解析木为研究对象,利用简单削度方程、分段削度方程和可变指数削度方程分别构建格木、红锥和柚木3个热带树种的干形曲线方程,通过相关指数、剩余残差平方和、平均残差、残差方差和均方误差统计量比较分析,找出最佳削度模型作为3个树种最终的干形曲线方程,并对各曲线变化趋势进行了初步的定量分析。结果表明,所选的3类典型基础模型对每个树种的预估效果都很好,其中基于双因素自动优选法拟合且以分段削度方程构建的干形曲线预估效果最好。3个树种的干形曲线变化趋势表明:相对高在(0~0.8)时,柚木干形变化最大,红锥干形变化最小,格木干形介于二者之间;当相对高>0.8时,红锥干形变化最大,格木和柚木干形变化几乎相同。因此,基于双因素自动优选法拟合的分段削度方程可作为3种热带树种的干形曲线方程,用于3种珍贵树种活立木蓄积量和材种数量的估计,以及指导合理造材。
Accurate description of dry tree species of tropical precious tree changes can be estimated for each species number, volume and reasonable material to provide support. In this paper, 120 precious tree species, including tropical lattice wood, red cone and teak, were selected for study. The simple tapping equation, piecewise tapping equation and variable index taper equation were used to construct grid wood, red cone and teak The dry curve equations of three tropical species were compared and analyzed by the correlation index, residual sum of squares of residuals, residuals of residuals, variance of residuals and mean square error statistics to find out the best tapping model as final dryness of the three species Shape curve equation, and the curve of the trend of a preliminary quantitative analysis. The results showed that the three selected typical base models had good estimation results for each tree species, of which the predictor based on the two-factor automatic optimization method and the stem-shaped curve constructed by the piecewise taper equation had the best prediction effect. The trend of dry curve of the three tree species showed that dry weight of teak was the highest at 0 ~ 0.8, and dry weight of red taper was the lowest, while that of dry wood was between 0.8 and 0.8 When the red cone dry shape changes the most, dry grid shape teak and wood changes are almost the same. Therefore, the piecewise taper equation based on the two-factor automatic optimization method can be used as the dry curve equation for the three tropical species, which is used to estimate the stock volume and the number of species of the three precious species and to guide rational timbering.