东大河林区青海云杉种群结构与动态

以"空间代时间"的方法,用种群大小级结构代替年龄结构,采用静态生命表、生存分析方法,探讨了东大河林区青海云杉种群的结构和动态规律。结果表明,东大河林区青海云杉种群结构合理,为增长型种群;种群存活曲线属Deevey-Ⅱ型,在整个生活史中死亡率稳定;种群的死亡数、生命期望和消失率分别在幼苗、幼树胸径达到14cm和22cm出现波动,个体通过环境筛的压力增大,种群生命表和存活曲线从整体上反映了东大河林区青海云杉种群数量动态变化趋势;在胸径达到14cm和22cm时,4个生存函数均出现程度不同的波动,与种群静态生命表分析结果吻合。

Structure and Dynamics of Picea crassifolia Population in Dongdahe Forest Area of Qilian Mountains Nature Reserve

With the method of spatial sere substituting for time sere,population size class structure substituting for age structure,and using standard life table and survival analysis,the structure and dynamics of Picea crassifolia population in Dongdahe forest area of Qilian Mountains Nature Reserve were studied.The results showed that the population structure in Dongdahe area was reasonable and it was an expanding population.Population survival curve accorded to DeeveyⅡ,the mortality rate was stable in all life history.Population mortality rate,life expectancy and the disappearance rate fluctuated in seedling and sapling stages,as well as when the tree DBH reached 14 cm and 22 cm.The pressure of individuals to pass the environmental sieve increased.Population life tables and survival curves well represented the population dynamics trends of P.crassifolia population.Four survival functions appeared changes with different levels while the DBH reached 14 cm and 22 cm,in accordance with the result of population standard life table.