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以北京九龙山面积为0.32 hm2样地调查数据为基础,采用传统方法及结构参数角尺度(W)、大小比数(U)和混交度(M)的二元分布法,分析了侧柏(Platycladus orientalis)人工林的空间结构多样性。结果表明:群落结构较为简单,侧柏占绝对优势,并处于低度混交、大小分化不明显且均匀分布状态,而其他伴生树种则处于高度混交与相对劣势状态;林分径级与树高结构呈单峰分布;侧柏林中平均59%的林木个体周围最近4株树均和它同种,22%林木个体周围最近4株树仅有一株其他树种,总体处于低度混交状态;侧柏样地有52%的林木呈随机分布,且处于随机分布状态的林木其周围57%都是本种,同时处于高度混交状态(M=0.75,1.00)的林木有50%呈随机分布;不同优势度的林木有相近的概率,但优势木略多于劣势木,且大多处于低度混交和随机分布状态。侧柏人工林的空间多样性是由混交度及直径分化共同决定的,这种结果不仅与群落的发展阶段密切相关,还与群落的起源、人为干扰以及物种组成有关。
Based on the survey data of Jiulongshan area of Beijing of 0.32 hm 2, the arborvitae (Arborvitae arborvitae) was analyzed by using the traditional method and the bivariate distribution of structure parameters of angular scale (W), size ratio (U) and mixing degree (M) Spatial Structure Diversity of Platycladus orientalis Plantations. The results showed that: the community structure is simple, arborvitae occupies the absolute dominant position, and is in the low degree of mixed, the size of the differentiation is not obvious and uniform distribution, while other associated species are in a high degree of mixed and relative disadvantage; stand diameter and tree height structure The distributions of the four species were the same as those of the other four species around the forest individuals in the average of 59% Fifty-two percent of the forest trees were randomly distributed, and 57% of the trees in random distribution were of the same species, while 50% of the trees in the highly mixed state (M = 0.75, 1.00) were randomly distributed; Of the trees have similar probability, but the dominant wood is slightly more than the inferior wood, and most of them are in low degree of mixed and random distribution. The spatial diversity of Platycladus orientalis plantations is determined by the degree of mixing and diameter differentiation, which is not only closely related to the stage of community development, but also to the origin of the community, human disturbance and species composition.