北京雾灵山保护区蒙椴林空间点格局分析

根据北京雾灵山自然保护区蒙椴林样地调查资料,采用点格局分析方法,对该群落的树种组成、优势种群及不同发育阶段种群的空间分布格局及其相互关系进行了研究。结果表明:1)蒙椴林中乔木层共有9个种群,种群密度差异较大,蒙椴种群的株数比例和断面积占有明显优势。2)蒙椴林优势种群的分布格局和空间关联性与空间尺度的关系密切,在研究尺度范围内,蒙椴种群和山杨种群均呈显著性聚集分布,白桦种群呈随机分布。优势种群的空间关联性以负关联为主,种间竞争激烈。3)不同发育阶段个体的空间格局随尺度的变化明显,大树在整个空间尺度上呈现随机分布,中树和幼树在中小尺度上(r<24m)呈显著性聚集分布,在较大尺度上呈随机分布。不同发育阶段种群之间空间关联性以负关联为主,当空间尺度大于临界值时,大树和中树、幼树的空间关联性减弱,而中树和幼树的负关联增强。

Spatial-Point-Pattern Analysis of Mongolian Linden in Beijing Wulingshan Nature Reserve

Based on the investigation data of Mongolian Linden plots in Beijing Wulingshan Nature Reserve,the method of point pattern analysis was employed to study the tree species composition of the community,the dominant population,and the spatial distribution pattern and interspecific relationship of the population in different development stages.The results show that:1) for the tree layer of Mongolian Linden,there are 9 populations,there is a great difference in population density,the proportions and the basal area of Mongolian Linden population take obvious advantages;2) The distribution pattern and the space correlation are closely related to the spatial scale of the dominant population of Mongolian Linden,in the research scale,both Mongolian Linden population and aspen population take significant aggregation distribution,birch population takes random distribution.The space correlation of the dominant population is mainly negative association,the interspecific competition is very fierce.3) The scale variation of the spatial pattern of individual is obvious,big tree took random distribution in the whole space scale,medium tree and young tree take significant aggregation distribution in county and village scale(r<24m) and random distribution in a larger scale.The space correlation of the populations is mainly negative association in different developmental stages,when the space scale is larger than the critical value,the space correlation among big tree,medium tree and young tree becomes weak,but the negative association between medium tree and young tree increases.