Bachmann Dörte, Buchmann Nina, Ebeling Anne, Roscher Christiane
Institute of Agricultural Sciences ETH Zurich Zurich Switzerland.
Institute of Ecology and Evolution Friedrich Schiller University Jena Jena Germany.
Ecol Evol. 2025 Sep 11;15(9):e72013. doi: 10.1002/ece3.72013. eCollection 2025 Sep.
Traits of the "leaf economics spectrum" (LES) relate to a functional trade-off between slow and fast return on carbon investment, but it is not clear whether the globally observed trait-relationships also hold in local plant communities. We studied four leaf traits associated with the LES in 20 grassland species, which represented different strategies in spatial resource acquisition (from small to large) and temporal resource acquisition (from early to late). Species were grouped into three partly overlapping pools of eight species to create a field experiment with 138 communities of varying species richness (1, 2, 3, 4, and 8 species), which either varied in spatial resource acquisition, temporal resource acquisition or both. Leaf nitrogen concentrations (N) and greenness (LeafG) decreased with species richness, while leaf dry matter content (LDMC) and specific leaf area (SLA) did not. Species with different spatial resource acquisition varied in leaf traits, suggesting that large species had "fast" traits (low LDMC, high N, dark LeafG), while small species had "slow" traits (high LDMC, low N, light LeafG). The extent of intraspecific trait variation (ITV) was smallest in LDMC and largest for N, but for all leaf traits, a greater portion of trait variation among communities was explained by interspecific trait variation (i.e., different species compositions) than ITV. Species with "fast" traits generally contributed more to total biomass than those with "slow" traits, but species biomass proportions did not always match expectations for all traits related to the "fast-slow" trade-off. Multi-trait analyses showed that trait relationships expected from LES were not always present, and were modified by ITV and trade-offs. In summary, independent responses of individual LES traits to local plant diversity lead to context-dependent trait-trait relationships, which cannot easily be interpreted as differences in growth strategies, and thus limiting the general applicability of LES in grassland communities.
“叶片经济谱”（LES）的特征与碳投资的慢回报和快回报之间的功能权衡有关，但全球观察到的特征关系在当地植物群落中是否也成立尚不清楚。我们研究了20种草种中与LES相关的四个叶片特征，这些草种代表了空间资源获取（从小型到大型）和时间资源获取（从早期到晚期）方面的不同策略。将这些物种分为三个部分重叠的八物种组，以创建一个包含138个不同物种丰富度（1、2、3、4和8个物种）群落的田间试验，这些群落要么在空间资源获取、时间资源获取方面有所不同，要么两者都不同。叶片氮浓度（N）和绿度（LeafG）随物种丰富度降低，而叶片干物质含量（LDMC）和比叶面积（SLA）则不然。具有不同空间资源获取方式的物种在叶片特征上存在差异，这表明大型物种具有“快”特征（低LDMC、高N、深LeafG），而小型物种具有“慢”特征（高LDMC、低N、浅LeafG）。种内特征变异（ITV）的程度在LDMC中最小，在N中最大，但对于所有叶片特征，群落间特征变异（即不同的物种组成）比ITV解释了更大比例的特征变异。具有“快”特征的物种通常比具有“慢”特征的物种对总生物量的贡献更大，但物种生物量比例并不总是与所有与“快 - 慢”权衡相关特征的预期相符。多特征分析表明，LES预期的特征关系并不总是存在，并且会受到ITV和权衡的影响。总之，单个LES特征对当地植物多样性的独立响应导致了依赖于环境的特征 - 特征关系，这很难被解释为生长策略的差异，从而限制了LES在草地群落中的普遍适用性。
