Data from: Contrasting patterns of leaf trait variation among and within species during tropical dry forest succession in Costa Rica

A coordinated response to environmental drivers amongst individual functional traits is central to the plant strategy concept. However, whether the trait co-ordination observed at the global scale occurs at other ecological scales (especially within species) remains an open question. Here, for sapling communities of two tropical dry forest types in Costa Rica, we show large differences amongst traits in the relative contribution of species turnover and intraspecific variation to their directional changes in response to environmental changes along a successional gradient. We studied the response of functional traits associated with the leaf economics spectrum and drought tolerance using intensive sampling to analyse inter- and intra-specific responses to environmental changes and ontogeny. Although the overall functional composition of the sapling communities changed during succession more through species turnover than through intraspecific trait variation, their relative contributions differed greatly amongst traits. For instance, community mean specific leaf area changed mostly due to intraspecific variation. Traits of the leaf economics spectrum showed decoupled responses to environmental drivers and ontogeny. These findings emphasise how divergent ecological mechanisms combine to cause great differences in changes of individual functional traits over environmental gradients and ecological scales.植物策略理论的核心在于，各功能性状间会针对环境驱动因子产生协同响应。然而，在全球尺度下观测到的性状协同格局，是否同样存在于其他生态尺度（尤其是种内尺度），仍是一个悬而未决的科学问题。本研究以哥斯达黎加两种热带干旱森林类型的幼树群落为研究对象，结果显示：沿演替梯度，物种周转与种内变异对功能性状沿环境变化产生的定向改变的相对贡献，在不同性状间存在显著差异。本研究通过密集采样，分析了功能性状对环境变化与个体发育的种间、种内响应，重点关注与叶经济谱（Leaf Economics Spectrum）及耐旱性相关的功能性状。尽管幼树群落的整体功能组成在演替过程中的变化更多依赖物种周转而非种内性状变异，但不同性状的相对贡献差异显著。例如，群落平均比叶面积（Specific Leaf Area）的变化主要源于种内变异。叶经济谱相关性状对环境驱动因子与个体发育的响应呈现解耦现象。本研究结果凸显了不同生态机制如何相互作用，使得单个功能性状沿环境梯度与生态尺度的变化产生显著差异。