中国大陆青冈分布区东缘大金山岛种群种子形态变异

在大陆青冈分布区东缘的大金山岛种群中按不同坡向取样,旨在揭示相对均一条件下青冈种子的形态变异及变异的来源,以从不同侧面研究环境对形态变异的作用。大金山岛种群青冈种子的长度、直径和重量分别为1.557±0.128cm、1.175±0.112cm、1.321±0.310g,处于青冈种子正常分布范围内。单颗种子的长度、直径符合正态分布,而重量则明显偏离正态分布。不同坡向青冈种子间差异很小,表明微地形的影响较小;种群变异的来源株内和株间约各占一半,说明种子表型具有一定的可塑性,主要由于种子处于植株不同部位的缘故。

Morphological variation of Cyclobalanopsis glauca seeds in Dajinshan Island, eastern edge of its distribution in mainland, China

The authors focus on such environment which is uniform in some way,to discuss the relationships between the morphological variation and environment.The morphological variation of Cyclobalanopsis glauca seeds in Dajinshan Island,located at the eastern edge of distribution in mainland China,was studied.Means of length,diameter and weight of seeds collected from 41 C.glauca trees were 1.557±0.128 cm,1.175±0.112 cm and 1.321±0.310 g,respectively.Normal distribution of seeds was observed in length and diameter,but not in weight.No distinct difference was found among seeds collected from different slope aspects,due to relative homogenous habitats.Gini coefficient showed that about half of the variation was partitioned within individual tree,indicating that microhabitats within individual tree might had a modification effect on the morphological characteristics of C.glauca seeds.