山西太岳山油松种群的空间分布格局

以太岳山油松林1.96 hm2的样地调查数据为基础,分析了油松种群的径级结构,应用R ip ley′s K函数探讨了油松不同生长阶段个体(幼树、小树和大树)的空间分布和空间关系。结果表明,油松径级结构呈单峰型,中径级的林木个体数较多。油松幼树和小树在空间上主要表现为聚集分布,大树表现为随机分布,聚集分布格局的形成与油松种子的扩散方式有关。不同生长阶段,种群分布格局不同,随着种群发育(幼树→小树→大树),油松的空间格局趋于随机分布,这体现了种群的一种生存策略或适应机制。种群的空间分布与空间关联具有较好的一致性,正关联的空间关系有利于种群对资源的利用,维护种群的正常生长。

Spatial distribution pattern of Pinus tabulaeformis population in Taiyue Mountain,Shanxi Province

Based on investigation data from a 1.96 hm~2 Pinus tabulaeformis forest plot in Taiyue Mountain, Shanxi Province. DBH structure of P.tabulaeformis population was analysed. Ripley′s K function was used to analyse spatial pattern and spatial association of P.tabulaeformis population in different growth stages (saplings, small trees and big trees). The results showed that DBH structure of P.tabulaeformis presented a unimodal distribution and middle age individuals accounted more. The spatial pattern of P.tabulaeformis population was clump for saplings and small trees, but random for big trees, seed dispersal mechanism was key factor to spatial pattern. Varied with growth stage (saplings→small trees→big trees), spatial pattern tended to be random, which showed the survival strategy and sutability in certain degree. Also, spatial pattern matched well with spatial association, positive correlation could help P.tabulaeformis population to utilize resources much better and maintain population growth.