Plasticity of functional traits of forb species in response to biodiversity
Plasticity of functional traits of forb species in response to biodiversity
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DOI：
10.1016/j.ppees.2014.11.003
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发表时间：
2015-01-01
影响因子：
3.6
通讯作者：
Schmid, Bernhard
中科院分区：
文献类型：
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作者：
Lipowsky, Annett;Roscher, Christiane;Schmid, Bernhard
尽管越来越多的人认识到种内变异可能对生态位分化起着重要的作用，而生态位分化被认为是物种共存的促进剂，但对功能性状变异的程度和结构对植物邻居多样性的响应却知之甚少。在不同物种丰富度和功能基团组成(含豆科和不含豆科)的试验草地(耶拿试验)中，研究了27种不同生长型(爬行型、莲座型、半莲座型)非豆科杂草营养枝和生殖枝功能性状的可塑性。与全枝结构相关的性状在不同生长方式的杂交种间差异较大，而与采光相关的叶片性状(比叶面积、叶增量C-13值)和与氮素营养相关的性状(地上部生物量：N比、叶片氮浓度、叶片增量N-15值)在杂交种中具有很高的可塑性。植株高度一般随物种丰富度的增加而增加。叶片性状(叶长、SLA、叶片增量C-13)对物种丰富度增加的可塑性在不同生长类型之间存在差异，并取决于发育阶段。豆类的存在通常会增加光获得性状的塑料反应，与增加物种丰富度的方向相同。在豆科植物存在的情况下，杂交种的组织氮素浓度较高，叶片增量N-15值不变，这表明豆科固氮植物的施肥效应是由于提供了未消耗的矿质氮。在与大小相关的性状中，性状均值和性状可塑性之间的相关性更强，这表明对光竞争的反应具有功能趋同。与植株大小无关的性状的可塑性谱更具变异性，表明物种之间存在更大的功能分离。我们的结果表明，种间差异和种内性状可塑性都影响着叉树物种之间的生态位分配，并且对于它们在多物种组合中的共存是重要的。(C)Stiftung Ruebel，2014 Gebotanisch Institut ETH。由Elsevier GmbH出版。版权所有。
In spite of increasing recognition that intraspecific variation may play an important role for niche differentiation, which is regarded as a promoter of species coexistence, the extent and structure of functional trait variation in response to plant neighbor diversity is poorly understood. We studied the plasticity of functional traits in vegetative and reproductive shoots of 27 non-legume forb species with different growth forms (reptant, rosulate, semirosulate) in experimental grasslands (Jena Experiment) of varying species richness and functional group composition (with and without legumes). Traits related to whole-shoot structure differed strongly among forb species with different growth forms, while leaf traits associated with light acquisition (specific leaf area, foliar delta C-13 values) and traits associated with nitrogen nutrition (shoot biomass:N ratios, leaf nitrogen concentrations, foliar delta N-15 values) were highly plastic within forb species. Plant height generally increased with increasing species richness. Plasticities to increased species richness in leaf traits (leaf length, SLA, foliar delta C-13) varied among growth forms and depended on developmental stage. The presence of legumes generally increased plastic responses in light-acquisition traits in the same direction as increasing species richness. Greater tissue nitrogen concentrations and unchanged foliar delta N-15 values of forb species in the presence of legumes suggested that the fertilizing effect of nitrogen-fixing legumes was due to the supply of unconsumed mineral nitrogen. Stronger correlations between trait means and trait plasticities in size-related traits suggested a functional convergence in response to light competition. A more variable spectrum in the plasticities of traits not associated with plant size indicated a greater functional separation among species. Our results suggest that both interspecific differences and intraspecific trait plasticity affect niche partitioning among forb species and are important for their coexistence in multi-species assemblages. (C) 2014 Geobotanisches Institut ETH, Stiftung Ruebel. Published by Elsevier GmbH. All rights reserved.