平陆后其凹南坡油松种群结构及动态分析

以种群径级结构代替年龄结构,采用静态生命表和生存分析方法,研究了平陆县后其凹山南坡不同海拔油松种群结构和动态规律。结果显示：该地区油松种群随着海拔从882 m,975 m升高到1 035 m,种群密度不断增大,径级分布范围逐渐减小,种群存活曲线由D eeveyⅡ型过渡到D eeveyⅠ型,种群由稳定型过渡为增长型,说明油松种群由低海拔到高海拔,处于不同的演替和发展阶段,且随着油松径级的增大,种群的平均生命期望陡降,预示着种群的生理衰退。结合生境条件可得出结论,土壤层厚度及水分是引起上述结果的主要原因。

Structure and Dynamics of Pinus tabulae formis Population on the Southern Slope of Houqiao Mountain

With the method of spatial sere substituting for time sere, by trunk size structure in place of age strucure, using life table and survival analysis, the structure and dynamics of Pinus tabulaeformis population at different elevation on the Southern slope of Houqiao were studied. Along the altitude the population aenslty lnereasea, distribution range of size class decreased, survival curves changed form Deevey Ⅱ type to Deevey Ⅰ type, and population size structure transited from stationary to growing type. It indicated that Pinus tabulaeformis population at different elevations developed at different stages. Moreover, with the tree growth, expected average life largely decreased, which indicated that the physiology of this population would be declined.