【作者】 汪殿蓓； 暨淑仪； 陈飞鹏； 彭少麟；

【Author】 WANG Dian-pei~1 JI Shu-yi~2 CHEN Fei-peng~2 PENG Shao-lin~(3*) 1 College of Life Science and Technology,Xiaogan University,Xiaogan 432000,Hubei,China; 2 College of Life Science,South China Agricultural University,Guangzhou 510640,China; 3 College of Life Science,Sun Yat-Sen University,Guangzhou 510275,China

【机构】 孝感学院生命科学技术学院； 华南农业大学生命科学学院； 中山大学生命科学学院；

【摘要】 运用种群静态生命表、存活曲线、生殖力表和Leslie矩阵模型,探讨了仙湖苏铁野生种群的数量动态特征,并采用生存函数对种群进行了生存分析。种群生命表和存活曲线反映出仙湖苏铁在Ⅰ龄级幼苗阶段(0～15a)和Ⅴ、Ⅵ龄级青壮年阶段(61-75a,76-90a)分别经历了强烈的环境筛作用以及竞争自疏和人工采挖;仙湖苏铁种群净增殖率、内禀增长率、周限增长率等均较低,种群表现为衰退种群;Leslie矩阵模型预测结果表明,150 a后种群个体将从目前的1613株/hm~2下降到59株/hm~2;生存分析结果表明,幼龄级个体具有较大危险率,中龄级个体具有高的累积死亡率和危险率,这将直接影响种群的自然更新而使得种群储备不足,最终导致种群的衰退消亡。种群衰退的原因可能与其自身生物学特性及生境日益恶化有关。更多还原

【Abstract】 Numeric dynamics of wild population of Cycas fairylakea mainly distributed in Shenzhen City were studied using the static life table,the survival curve,the fecundity schedule and the Leslie matrix model.The viability of the population was analyzed by viability functions.Analytical results from the life table and survival curve reflected that Cycas fairylakea underwent very strong environmental screening during classⅠ(0～15a) and competitive self-thinning,human excavation at the classⅤVandⅥ(61-75a,76-90a).The net reproductive rate,the intrinsic rate and the finite rate of increase of Cycas fairylakea population were relatively low,indicating that the population is of the declining type.Results from the Leslie matrix model show that the individuals will decline from 1613/km~2 to 59/km~2 in 150a.The viability analysis shows that the individuals of seedling have large hazard rate and the middle-age individuals have high cumulative rate and hazard rate,which will affect natural regeneration of the population and lead to the lack of seedling,at last will cause the population declining,and death.The possible factors leading to the population being in declining are its biological characteristics and the increasing deterioration of habit.更多还原