【摘要】 分析种群数量特征和分布格局有利于认识种群的更新、稳定性及演替,可为其经营与保护提供参考依据。本研究以赣中闽楠(Phoebe bournei)天然种群为对象,通过标准地调查获取数据,对种群的径级结构、静态生命表进行分析,运用存活曲线分析种群动态数量特征,采用扩散系数及丛生指数进行种群分布格局分析。结果表明:种群幼苗(D<2 cm)、幼树(2 cm≤D<5 cm)、小树(5 cm≤D<10 cm)、中树(10 cm≤D<20 cm)、大树(20 cm≤D<40 cm)和老树(D≥40 cm)占总株数的比例分别为57.93%、13.14%、12.91%、9.49%、4.96%和1.59%,其径级结构总体上呈倒"J"型;种群在D<2 cm且H>1 m、5 cm≤D<10 cm和60cm≤D<65 cm三个阶段的死亡率均超过了50%,在25 cm≤D<30 cm阶段生命期望值最大(ex=4.50);种群存活曲线趋于Deevey-Ⅱ型,属于增长型且趋于稳定型的种群,对外界干扰敏感度较高;种群分布格局总体上为聚集分布,且随着尺度的增大聚集强度减小,从幼苗—幼树—小树—中树—大树—老树阶段由聚集度高向聚集度低、聚集分布向随机分布方向发展。更多还原

【Abstract】 Analyzing quantitative characteristics and distribution pattern of population is helpful for understanding population renewal,stability and succession. This study aimed to clarify the structure of natural population of Phoebe bournei in central Jiangxi. With data from field survey,population characteristics were studied based on the survivorship curve and quantitative analysis method. Population distribution pattern was analyzed with the diffusion coefficient and aggregation intensity index. The proportion of seedlings( D<2 cm),saplings( 2 cm≤D<5 cm),small trees( 5 cm≤D<10 cm),medium trees( 10 cm≤D<20 cm),large trees( 20 cm≤D<40 cm) and old trees( D≥40 cm) accounted for 57.93%,13.14%,12.91%,9.49%,4.96% and 1.59% of the total abundance,respectively. The diameter structure of the population as a whole was generally an inverse-J type. The mortality of the population at three stages of D<2 cm and H>1 m,5 cm≤D<10 cm and 60 cm≤D<65 cm all exceeded 50%. The life expectancy was the highest at25 cm≤D<30 cm( ex= 4.50). The survivorship curve of the population was the Deevey-II type,which belonged to the growing and stable population and was more sensitive to external disturbances. The population distribution pattern was generally aggregated,with the aggregation intensity decreasing with scales. From the stages of seedlings,saplings,small trees,medium trees,large trees to old trees,the distribution pattern changed from high aggregation to low aggregation,with the aggregated distribution developing towards a random direction.更多还原