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【目的】红松和长白落叶松是黑龙江省主要的造林树种,构建两个针叶树树冠外部轮廓预估模型,为进一步科学合理的经营人工林提供基础。【方法】采用黑龙江省人工红松和长白落叶松各50株解析木的枝条解析数据,以分段抛物线方程、修正Kozak和Weibull方程为基础模型,构建以样木为单一水平树冠外部轮廓的非线性混合效应模型,并对2树种的树冠轮廓进行比较。【结果】2树种树冠外部轮廓的分段抛物线预估模型包含的变量为DBH、CL、CR、HD,修正Kozak预估模型包含的变量为DBH、CR、HD,修正Weibull预估模型包含的变量为DBH、CR、HD。加入混合效应后,各模型的拟合效果较基础模型均有所提高。修正Weibull方程对红松和长白落叶松的拟合效果最好,但与分段抛物线方程和修正Kozak方程之间的差别不是很大。对于红松,分段抛物线方程预估的树冠半径在靠近树冠基部要低于修正的Kozak方程和修正的Weibull方程;对于长白落叶松,各模型之间的拟合效果差别较小。【结论】分段抛物线方程、修正Kozak和Weibull方程均能够对黑龙江省人工红松和长白落叶松树冠外部轮廓进行比较准确的模拟。修正Kozak方程和Weibull方程包含的树木变量较少,参数估计相对简单,容易通过积分计算树冠体积及表面积。
【Objective】 Pinus koraiensis and Larix principis-rupprechtii were the main afforestation species in Heilongjiang Province. Two contour models of conifer crown were constructed, which provided the basis for further scientific and rational plantation management. 【Method】 The analytical data of 50 branches of Artemisia affinis and Larix principis-rupprechtii in Heilongjiang Province were analyzed. Based on the piecewise parabolic equation and the Kozak and Weibull equations, the model was constructed based on Kozak and Weibull equations. Linear mixed effects model, and compared the tree crown contour of two species. 【Result】 The results indicated that the segmentation parabola estimation model of tree crown outer contour included DBH, CL, CR and HD. The modified Kozak model included DBH, CR and HD, and the variables contained in Weibull’s prediction model were modified For DBH, CR, HD. After adding the mixed effect, the fitting effect of each model is better than the basic model. The modified Weibull equation has the best fitting effect on Korean pine and Korean white larch, but the difference between the piecewise parabolic equation and the modified Kozak equation is not very large. For the Korean pine, the estimated crown radius of the piecewise parabolic equation is lower than the modified Kozak equation and the modified Weibull equation near the base of the canopy. For the Larix olgensis, there is little difference between the models. 【Conclusion】 The sectional parabolic equation and the modified Kozak and Weibull equations can all be used to simulate the external contour of artificial crown of Larix sibirica and Larix gmelinii in Heilongjiang Province. Correcting the Kozak equation and the Weibull equation contains fewer tree variables, the parameter estimation is relatively simple, and the crown volume and surface area are easily calculated by integration.