摘要：
The purpose of this study was to explore the distribution regularity of the diameter of different origin,and to provide theoretical and methodological bases for the management of Pinus yunnanensis stands.Based on the survey data,the diameter distribution of natural and aerially seeded forests of Pinus yunnanensis were separately fitted with Normal,Weibull,Beta and Gamma distribution functions,and all the distributions were checked by x2-test.Majorities of P.yunnanensis trees were in small and mediumsized diameter,comparatively,less in large diameter.The diameter distribution curves significantly slanted to the left,besides,the variation of the diameter distribution changed much more.The aerially seeded stands had a narrow distribution,therefore the competition between them was keen.On the other hand,the dispersion of natural stands was larger,but the number of subsequent trees was insufficient.Normal model and Gamma model were inconsistent with the actual situations,from which the overall estimations on the tree number were too small.With higher compliance in all diameter distribution,Weibull model and Beta model showed good adaptability and flexibility,they were more suitable to describe the diameter distribution of P.yunnanensis.%研究不同起源林分的直径分布规律,为云南松科学经营提供理论和方法论依据.利用样地调查数据,运用Normal、Weibull、Beta和Gamma概率密度函数拟合了云南松天然林和飞播林的直径分布,并对径阶分布数据进行x2检验.结果表明,川西南高原云南松中等偏小胸径林木占大多数,大径阶林木少,直径分布曲线严重左偏,林木直径变动程度较大.飞播林直径分布集中,生长竞争剧烈,天然林离散程度大,后续林木数量不足.模型拟合结果显示,Normal模型和Gamma模型拟合曲线形态与实际不符,总体估计株数偏小;Weibull模型和Beta模型表现出了较好的适应性和灵活性,在整个径阶范围内具有较高的符合度,更适于描述该地云南松直径分布规律.
