Leaf venations have elements with relatively lower elasticity than other leaf tissue components, which are thought to contribute to leaf biomechanics. A better mechanistic understanding of relationships between vein traits and leaf mechanical properties is essential for ecologically relevant interpretation of leaf structural variations. We investigated 13 major (first to third order) and minor (>third order) vein traits, six leaf mechanical properties and other structural traits across 58 woody species from a subtropical forest to elucidate how vein traits contribute to leaf biomechanics. Across species, vein dry mass density (ρv ), total vein dry mass per leaf area (VMA) and minor vein diameter (VDmin ), but not the lower-order vein density (VLA1•2 ), were positively correlated with leaf force to punch (Fp ) and force to tear (Ft ). Structural equation models showed that ρv and VDmin not only contribute to leaf mechanical properties directly (direct pathway), but also had impacts on leaf biomechanics by influencing leaf thickness and leaf dry mass per area (indirect pathway). Our study demonstrated that vein dry mass density and minor vein diameter are the key vein properties for leaf biomechanics. We also suggest that the mechanical characteristics of venations are potential factors influencing leaf mechanical resistance, structure and leaf economics spectrum.

中文翻译：

---

将来自亚热带森林的58种木本植物的脉脉特性与叶片生物力学联系起来。

叶脉具有比其他叶组织成分相对较低的弹性的元素，据认为这有助于叶的生物力学。对叶性状与叶片机械特性之间关系的更好的机械理解，对于生态学上解释叶片结构变化至关重要。我们调查了亚热带森林中58种木本植物的13种主要（一阶至三阶）和次要（>三阶）静脉性状，六个叶片机械特性和其他结构性状，以阐明静脉性状如何促进叶片生物力学。跨物种，静脉干重密度（ρv），每叶面积总静脉干重（VMA）和次要静脉直径（VDmin），而不是低阶静脉密度（VLA1•2）与叶片力的正相关。打孔（Fp）并强行撕开（Ft）。结构方程模型表明，ρv和VDmin不仅直接影响叶片机械性能（直接途径），而且通过影响叶片厚度和单位面积的叶片干质量（间接途径）对叶片生物力学产生影响。我们的研究表明，静脉干物质密度和较小的静脉直径是叶片生物力学的关键静脉特性。我们还建议，脉管的机械特性是影响叶片机械阻力，结构和叶片经济性谱的潜在因素。我们的研究表明，静脉干物质密度和较小的静脉直径是叶片生物力学的关键静脉特性。我们还建议，脉管的机械特性是影响叶片机械阻力，结构和叶片经济性谱的潜在因素。我们的研究表明，静脉干物质密度和较小的静脉直径是叶片生物力学的关键静脉特性。我们还建议，脉管的机械特性是影响叶片机械阻力，结构和叶片经济性谱的潜在因素。