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选取4种密度的红松人工林,设置15块25 m×40 m的临时样地,采用单因素Logistic回归分析和Meta分析方法定量分析了不同杈干类型与红松林分密度、树高、胸径、冠幅及丰年结实量的关系。结果表明:杈干率随着密度的增大呈现降低趋势,与密度600株·hm~(-2)相比,密度750、900和1200株·hm-2的杈干发生概率分别降低了24%、51%和59%;3种杈干类型中以双杈为主,样地内双杈类型株数占杈干总株数的60%以上;杈干对红松各项生长指标和丰年结实量均有显著影响(P≤0.05),杈干木的平均树高、胸径、冠幅和丰年单株球果产量与未杈干木相比分别增加了2.12%、4.69%、4.89%和29.57%;不同杈干类型对红松树高、胸径和结实的影响规律不同,单杈类型对红松生长和结实指标影响不显著(P>0.05),其平均树高、胸径、冠幅、丰年单株结实量分别比未杈干类型增加了1.49%、1.99%、1.47%和20.64%;双杈和多杈干类型的各指标与未杈干类型相比有显著差异(P≤0.05),其平均树高、胸径、冠幅及丰年单株球果产量比未杈干木分别增加了2.07%和2.90%,6.00%和6.09%,6.29%和5.99%,及34.61%和26.22%。Logistic回归模型和Meta分析结果证明,红松杈干木对生长结实的促进效应明显,其中双杈和多杈干类型的促进效应表现明显,单杈木的杈干效应不明显,40 a左右的红松人工林杈干效应在林分密度600~750株·hm~(-2)是最佳的。
Four kinds of density Korean pine plantations were selected and 15 temporary plots of 25 m × 40 m were set up. The single factor Logistic regression analysis and Meta analysis were used to quantitatively analyze the differences of branch types, the stand density, , The crown and the abundance of Fengnian the relationship. The results showed that the percentage of stems decreased with the increasing of density. Compared with the density of 600 plants · hm -2, the stems of 750, 900 and 1200 plants · hm-2 decreased the probability of stem twigs by 24 %, 51% and 59% respectively. The two types of stems were dominated by double twigs, and the number of double twigs was more than 60% of the total number of stems in the sample plots. (P≤0.05). The average tree height, diameter at breast height, crown width and fruit yield per plant per plant were increased by 2.12%, 4.69%, 4.89% and 29.57% respectively compared with those of unripe dry wood. The effects of different types of stems on the height, DBH and firmness of Korean pine trees were different. The types of single twigs had no significant effects on the growth and fruiting of Korean pine (P> 0.05). The mean tree height, DBH, (P≤0.05), the average tree weight of the two types of branches increased by 1.49%, 1.99%, 1.47% and 20.64%, respectively. The yield per plant of high, DBH, crown and harvest was 2.07% and 2.90%, 6.00% and 6.09%, 6.29% and 5.99% and 34.61% and 26.22% higher than that of the non-stem dry wood. Logistic regression model and Meta-analysis results showed that the promotion effect of the dry wood of Pinus koraiensis on growth and fruiting was obvious. The promotion effect of the two-branch and the multiple-branch type was obvious. The twig dry effect of the single branch was not obvious. About 40 years The dry effect of Korean pine plantation was the best in stand density of 600-750 plants · hm -2.