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以吉林汪清林区臭松次生林为对象,分析了臭松次生林的树种组成和直径结构规律。采用威布尔分布(Weibull)、伽马(Gamma)及对数正态分布(logarithmic normal)进行直径拟合并进行卡方检验,研究表明:臭松林分平均直径为15.1cm,最小直径为5.1cm,最大直径为47.1cm,6—28径阶的林木株数所占比重最多,达75.8%,3种分布函数中,威布尔分布的R2为0.997,卡方(χ2)为6.35,拟合效果最好,伽马分布次之,对数正态分布最差,但前两者的差异不大,故威布尔分布和伽马分布适用于臭松林直径结构预测,可为臭松次生林直径结构和林分密度调整提供理论依据。
Taking the secondary forest of Smectus massoniana in Wangqing forest area of Jilin as an example, the tree species composition and diameter structure of secondary forest of Slash pine were analyzed. Weigull, Gamma and logarithmic normal were used for diameter fitting and chi-square test. The results showed that the average diameter of stinks was 15.1 cm and the minimum diameter was 5.1 cm , The largest diameter was 47.1cm, and the diameter of 6-28 diameter trees accounted for the largest proportion (75.8%). Among the three distribution functions, the R2 of Weibull distribution was 0.997 and the chi square (χ2) was 6.35 Good, gamma distribution followed by the lognormal distribution of the worst, but the difference between the former two is not, so weibull distribution and gamma distribution is suitable for the prediction of stomatal diameter structure, Density adjustment provides the theoretical basis.