Conservation Research Institute and Department of Plant Sciences, University of Cambridge, Cambridge, UK.
School of Biological Sciences, University of Bristol, Bristol, UK.
Ecol Lett. 2024 Sep;27(9):e14527. doi: 10.1111/ele.14527.
In tropical forests, trees strategically balance growth patterns to optimise fitness amid multiple environmental stressors. Wind poses the primary risk to a tree's mechanical stability, prompting developments such as thicker trunks to withstand the bending forces. Therefore, a trade-off in resource allocation exists between diameter growth and vertical growth to compete for light. We explore this trade-off by measuring the relative wind mortality risk for 95 trees in a tropical forest in Panama and testing how it varies with tree size, species and wind exposure. Surprisingly, local wind exposure and tree size had minimal impact on wind mortality risk; instead, species wood density emerged as the crucial factor. Low wood density species exhibited a significantly greater wind mortality risk, suggesting a prioritisation of competition for light over biomechanical stability. Our study highlights the pivotal role of wind safety in shaping the life-history strategy of trees and structuring diverse tropical forests.
在热带森林中，树木会根据多种环境胁迫因素，战略性地平衡生长模式，以优化适应能力。风是树木机械稳定性面临的主要威胁，促使树木发展出更粗的树干以抵御弯曲力。因此，树木在分配资源时会在直径生长和垂直生长之间进行权衡，以争夺阳光。我们通过测量巴拿马热带森林中 95 棵树的相对风害死亡率，并测试其如何随树体大小、物种和受风暴露程度而变化，来探讨这种权衡关系。令人惊讶的是，当地的风暴露和树木大小对风害死亡率的影响很小；相反，物种的木材密度成为关键因素。低木材密度的物种表现出显著更高的风害死亡率，这表明它们更倾向于优先竞争阳光，而不是生物力学稳定性。我们的研究强调了风安全在塑造树木生活史策略和构建多样化热带森林方面的关键作用。
