Are shade tolerance and canopy gradient affecting twig-leaf trait scaling relationships in temperate forests?  

耐阴性和冠层梯度影响温带森林中枝条-叶片性状的尺度关系

作　　者：Tao Zeng Hongkun Fan Guangze Jin Zhili Liu 

机构地区：[1]School of Ecology,Northeast Forestry University,Harbin 150040,China [2]Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education,Northeast Forestry University,Harbin 150040,China [3]Northeast Asia Biodiversity Research Center,Northeast Forestry University,Harbin 150040,China

出　　处：《Journal of Plant Ecology》2024年第6期209-224,共16页植物生态学报(英文版)

基　　金：supported by the National Key R&D Program of China(2022YFD2201100);the National Natural Science Foundation of China(32071533);the Fundamental Research Funds for the Central Universities(2572022DS13).

摘　　要：Scaling relationships among twig size,leaf size and leafing intensity is pivotal in understanding plant resource allocation and carbon investment strategies.However,it remained unclear how these relationships might maintain stability across genetic traits(shade tolerance)and canopy gradients(microclimates).We investigated eight different shade-tolerant tree species within five mixed broad-leaved-Korean pine(Pinus koraiensis)forests in Northeast China.Employing linear mixed-effects models and phylogenetically independent contrasts,we examined the scaling relationships between twig-leaf size and leafing intensity.Shade tolerance altered the scaling relationships between twig and leaf size,as well as leafing intensity.We discovered that the scaling relationships between twig cross-sectional area and individual leaf area,leafing intensity and between individual leaf mass and leafing intensity were allometric(slope≠−1 or 1).However,the relationship between individual leaf area and individual leaf mass was isometric(slope=1).Moreover,these scaling relationships exhibited consistent trends across canopy gradients,with shade tolerance playing a critical role in the coordinated evolution of twigs and leaves across these gradients.These results emphasized the significant role of shade tolerance in coordinating the covariation patterns between plant leaves and twigs,adopting conservative strategies in heterogeneous microclimates.枝条大小、叶片大小和出叶强度之间的尺度关系对于理解植物资源分配和碳投资策略至关重要。然而,目前尚不清楚这些关系如何在遗传性状(耐阴性)和冠层梯度(微气候)之间保持稳定性。本研究以中国东北的5个阔叶红松(Pinus koraiensis)混交林中具有不同耐阴性的8种树种为研究对象,采用线性混合效应模型和系统发育独立比较分析,研究了枝条大小与叶片大小及出叶强度之间的尺度关系。研究结果表明,耐阴性改变了枝条大小与叶片大小及出叶强度之间的尺度关系。枝横截面积与单叶面积、出叶强度之间,以及单叶干质量和出叶强度之间呈异速生长关系(斜率≠-1或1),而单叶面积与单叶干质量之间呈等速生长关系(斜率=1)。此外,这些尺度关系在冠层梯度之间表现出一致的趋势,而耐阴性在不同冠层梯度上对枝条和叶片的协调进化具有关键作用。本研究强调了耐阴性在协调植物叶片与枝条之间协同变化模式中的重要作用,尤其在异质性微气候中采用的保守策略,进而为认识植物资源分配模式提供了新的见解。

关 键 词：allometric scaling shade tolerance index CANOPY leafng intensity twig leaf size relationship Corner’s rule 

分 类 号：O17[理学—数学]