桂东南福建柏林分直径结构研究

目的]研究桂东南福建柏林分直径结构。方法]以桂东南福建柏人工林为研究对象,采用典型选样法设置15个20 m×20 m的样方,开展植物群落调查。以2 cm为径阶距,应用理论生长方程Richards,Logistic,Gompertz,Mitscherlich和Weibull分布函数对林分直径分布进行拟合,采用卡方检验法对5种分布进行检验。结果]福建柏林分平均胸径19.3 cm,在5.7~29.8 cm,以20 cm为峰点,16~24 cm的林木株数占多数,单峰近似于正态分布,24 cm的株数累积频率高达93.64%;林分直径分布拟合检验结果从大到小依次为Weibull,Logistic,Gompertz,Richards,Mitscherlich。结论]Weibull分布函数更能准确地描述桂东南福建柏林分直径分布规律,更适合于建立福建柏林分直径分布预测模型。

Study on the Diameter Structure of Fokienia hodginsii Plantation in Southeast of Guangxi

Objective]To study the diameter structure of Fujian and Berlin in Southeast Guangxi.Method]Fokienia hodginsii plantations dis-tributed in Southeast Guangxi were studied.Plant community investigation was carried out based on 15 plots with 20 m ×20 m areas.With 2 cm as a diameter class distance, the stand diameter distribution was fitted by using Richards, Logistic, Gompertz, and Mitscherlich theoretical growth equations, and Weibull function combined with Chi-square test. Result] The results showed that the average diameter at breast height (DBH) of Fokienia hodginsii plantation was19.3 cm, ranging from 5.7 cm to 29.8 cm.The diameter rank distribution was singlet and similar to normal distribution, with 20 cm as the peak point.16 ~24 cm DBH standing trees were in the majority, and the accumulative percentage of 24 cm diameter class was up to 93.64%.The test values of forest diameter distribution fitting from big to small were Weibull, Logistic, Gomper-tz, Richards, Mitscherlich.Conclusion]The fitting effect of Weibull function could precisely describe the diameter distribution of Fokienia hod-ginsii plantation in Southeast Guangxi, which was suitable for establishing the diameter distribution prediction model for this forest.