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作 者 ：邱迎君;李作洲;黄宏文

期 刊 ：武汉植物学研究 2008年 26卷 5期 页码：495-500

关键词：长苞铁杉；空间格局；年龄结构；濒危植物；

Keywords:Nothotsuga longibracteata, Spatial patterns, Age structure, Endangered plant,

摘 要 ：长苞铁杉(Nothotsuga longibracteata)是我国特有的古老孑遗的单种属植物,对研究松科植物的系统发育及古生态、古气候具有重要价值。对福建天宝岩自然保护区长苞铁杉天然林的群落组成、年龄结构和各年龄级的空间分布格局进行了研究。通过设置60m×72m的样方,对样方内所有215株长苞铁杉个体定位并划分为16个年龄段,统计伴生种的种类及数量,用Ripley’s K(d)函数对各年龄段个体进行空间格局分析。结果表明,伴生种主要为常绿和落叶阔叶树种,不利于长苞铁杉幼苗的更新;该种群经历了3个阶段性的更新期,可能与群落中林窗的形成或周期性的干扰有关;在35m的半径范围内,长苞铁杉60年以下年龄级个体呈显著的聚集分布,60年以上年龄级个体则变为随机分布,主要是由于长苞铁杉的种子散布和生长特性、种群内和种群间的竞争、种群的自我稀疏过程造成的。

Abstract:Nothotsuga longibracteata,a relic plant endemic to Southeastern China,is now distributed in highly isolated mountain forests.The species is important for Pinaceae in the studies of phylogeny and phylogeography.The present paper based on field investigations to a well conserved natural N.longibracteataN.logibracteata population.The age of all individual plants in the plot were measured by taking tree cores,and all individuals were mapped. A total of 215 N.longibracteata individuals were grouped into 16 age-classes. The spatial patterns analysis was conducted using Ripley’s K(d).The results showed that the companion understory species were mainly broad-leaved evergreen trees which seemed to hamper the seedling regeneration of N.longibracteata.The age structure of N.longibracteata showed the population has experiments three main regeneration periods which might have been interrupted by disturbances.The data showed that in the radius of 35 m,the N.longibracteata population younger than 60 a has a patchy spatial distribution,the pattern then becomes random as the age increases over 60 a.The spatial structures in different age classes seemed to be highly influenced by natural regeneration characters, seed dispersal patterns, intra-and inter-specific competition and self-thinning processes.These results can be used as a baseline data for formulating conservation strategies of N.longibracteata in the reserve.

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