广西猫儿山鹅掌楸天然种群动态研究

Population structure dynamics of Liriodendron chinensis, a case study on a natural population in Maoer Mountain, Guangxi

关键词:  鹅掌楸  龄级  静态生命表  种群结构  动态

Key words:  Liriodendron chinensis  age class  static life table  population structure  dynamics

摘要:

为进一步探讨鹅掌楸濒危的机制,对广西桂林猫儿山鹅掌楸天然种群进行了调查,以种群生命表及生存分析理论为基础,以林木径级结构代表龄级结构,编制鹅掌楸种群静态生命表,分析种群结构的动态变化特点。结果表明:鹅掌楸种群龄级结构为金字塔型,幼龄个体数量较多,中龄个体数居中,而老龄个体则相对数量较少,表现为增长型种群; 在第Ⅳ龄级时该种群出现死亡高峰,其种群存活曲线属Deevey-Ⅱ型; 猫儿山鹅掌楸天然种群具有前期种群数量快速减少,中后期稳定,末期衰退的特点。该研究结果对鹅掌楸天然种群的保护提供参考依据。

Abstract:

In order to provide reference and further explore endangered mechanism of Liriodendron chinensis natural populations the population structure dynamic of L.chinensis was analyzed by taking a natural population in Maoer Mountain of Guilin,Guangxi,as a sample. Based on the theory of population life table and survival analysis,the life table of L.chinensis population was constructed by replacing age classes with size-classes,and the population structure dynamic of L.chinensis was explored. The census data showed that the number of young seedling was larger than that of middle aged and old individuals,indicating that the population was in an incremental status. The survival curve in this population appeared to be a Deevey-Ⅱ type,with a peak of mortality in size class Ⅳ. It can be concluded that the population size of L.chinensis in Maoer mountain declined sharply in early stage,stablized in middle stage and fell rapidly in last stage.