从叶内生物量分配策略的角度理解叶大小的优化  

Biomass allocation strategies within a leaf: Implication for leaf size optimization

作　　者：潘少安 彭国全 杨冬梅[1] 

机构地区：[1]浙江师范大学化学与生命科学学院,浙江金华321004 [2]秦岭国家植物园,西安710061

出　　处：《植物生态学报》2015年第10期971-979,共9页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金(31000193)

摘　　要：叶大小的变化是许多因素综合作用的结果,对叶大小优化机制的研究有助于我们更好地理解植物的适应进化和生活史策略。该研究通过对浙江省清凉峰常绿阔叶混交林中的19个常绿阔叶物种和30个落叶阔叶物种叶水平上的相关性状进行分析,探讨叶内生物量分配策略对叶大小优化的限制性影响。研究结果显示:无论叶大小用面积还是质量表示,常绿物种和落叶物种均呈现出叶内生物量分配到支撑结构的比例随着叶大小的增加而增加的规律,这主要是由叶柄大小与叶片大小之间显著的异速生长关系导致的。这种异速生长关系在常绿物种和落叶物种中普遍存在。然而,由于常绿物种对叶柄具有较高的机械以及抵抗冰冻栓塞等不利环境的需求,在某一给定的叶面积下,常绿物种比落叶物种具有更高的叶柄生物量投资。这些结果表明:作为整个植株支撑投资的一个重要组成部分,叶内支撑投资所占的生物量比例对叶大小的优化具有一定的限制性影响。Aims The variations in leaf size result from the integrated effects of many factors. Study of the mechanism to reach the optimum leaf size could help us better understand plant adaption and evolution, and plant life history strategies. Here we aim to test the hypothesis that leaf size is affected by the biomass allocation strategy within a leaf. Methods The relationships between leaf size and different biomass partitioning patterns within a leaf were studied for 19 evergreen and 30 deciduous broadleaved woody species from Qingliang Mountain, Zhejiang, China. The standardized major axis estimation method was used to examine the scaling relationship between lamina size and petiole size within a leaf. The relationship between leaf size and support investment ratio within a leaf was estimated by the Model Type I regression analysis. Important findings Biomass allocation in petiole increased with leaf size similarly in both evergreen and deciduous leaves, which resulted from the significant allometric scaling relationship between petiole mass and lamina mass（and area） with slopes significantly larger than 1.0, independent of leaf habit. However, evergreen species were found to have a greater petiole mass at a given lamina mass or area than deciduous species, which may be due to their higher demand for mechanic support and resistance to freezing-induced embolism in petioles. Results suggest that leaf size could be affected by the fraction of support investment within a leaf.

关 键 词：异速生长 生物量分配 叶片习性 叶大小 支撑投资 

分 类 号：Q944.3[生物学—植物学]