摘要
利用保护区30a长期固定观测资料,采用5种模型对白石砬子国家级自然保护区中5种林型的林木直径分布进行拟合,并对不同林型的拟合效果进行了分析;采用威布尔模型对林分30a的动态直径变化规律进行了研究。结果表明:几种主要林型的胸径静态分布都不同程度的呈现出天然林倒"J"形曲线的特征,所不同的是落叶松林模型拟合效果要好于其他林型,分析表明,威布尔分布模型和伽玛分布模型对保护区森林不同树种的拟合,有很好的适应性和灵活性;随着胸径、林龄的不断增大,直径分布形状也发生规律性的变化,不同林型的直径分布曲线表现出由指数形转向倒"J"形至近似正态分布,偏度由正偏趋于负偏,峭度逐渐变小的动态分布规律。
Five kinds of distribution models were used to fit the diameter distribution of five forest types by means of the data from 64 fixed sample plots in Baishilazi Nature Reserve for 30 years. The fitting effects of the models for different forest types were analysed,and the dynamic change of stand diameter for 30 years was studied by Weibull model. Results showed that the distribution of diameter at breast height for several main forest types presented an inverted J-shaped curve to various degrees,among which the fitting effect of the diameter prediction model for larch forest was better than that for other forest types. Weibull model and Gamma model showed strong adaptability and flexibility in fitting different forest types in Baishilazi Nature Reserve. With diameter at breast height and stand age increasing,the curve shape of diameter distribution changed regularly. Diameter distribution curves for different forest types changed from exponential form to inverted J-shaped curve,and then to approximately normal distribution,and the skewness changed from positive bias toward negative side and the kurtosis gradually decreased.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2010年第5期20-23,共4页
Journal of Northeast Forestry University
基金
国家科技支撑计划项目(2008BADB0B0302)资助
关键词
直径分布
动态预测
白石砬子保护区
Stand structures
Dynamic forecast
Baishilazi Nature Reserve
