北京山区油松天然林的空间结构分析

在北京市松山自然保护区设立面积为0.8 hm2的样地,对胸径大于5 cm以上的林木进行每木定位调查,利用角尺度、大小比数和混交度3个林分空间结构参数,分析了油松天然林的空间结构特征。结果表明:①油松天然林物种多样性丰富,乔木层共出现17个种群,油松种群优势度明显,为该群落乔木层的优势种,也是建群种;②用林分平均混交度和混交度分布分析了树种空间配置情况,油松林主要以零度混交和弱度混交为主,林分混交程度较低;③林木大小比数分析表明,油松种群在空间结构单元中,林木大小比数的分布较均匀,伴生树种分化程度差异较大,核桃楸种群、辽东栎种群和大果榆种群的优势木、亚优势木较多;④用平均角尺度和角尺度分布分析了林木水平分布格局,表明该林分整体上的林木水平分布格局为随机分布。

Analysis the Pinus Tabulaeformis Natural Forest Spatial Structure

In order to revealed the spatial structure of natural forests,and rational management Pinus tabulaeformis,0.8 hm2 plot was set in Beijing nature reserve,the diameter larger than 5 cm were location investigated,and uniform angle index,neighborhood comparison,and mingling degree were used to analysis spatial structure of Pinus tabulaeformis.The results showed that: ①The species diversity of Pinus tabulaeformis is rich,there are 17 stocks in tree layer,dominance of the Pinus tabulaeformis.population is obvious.And it is the dominance of the tree layer of the population,and also the constructive species.②Zero mix and weak mix are the main of the Pinus tabulaeformis,the mixed degree of the forest is low.③Neighborhood comparison of the Pinus tabulaeformis spatial structure is uniform,differentiation of the associated tree is big.④The distribution pattern of the overall stand trees is random distribution.