© 2020 John Wiley & Sons Ltd Aim: Mapping tree species richness across the tropics is of great interest for effective conservation and biodiversity management. In this study, we evaluated the potential of full-waveform lidar data for mapping tree species richness across the tropics by relating measurements of vertical canopy structure, as a proxy for the occupation of vertical niche space, to tree species richness. Location: Tropics. Time period: Present. Major taxa studied: Trees. Methods: First, we evaluated the characteristics of vertical canopy structure across 15 study sites using (simulated) large-footprint full-waveform lidar data (22 m diameter) and related these findings to in-situ tree species information. Then, we developed structure–richness models at the local (within 25–50 ha plots), regional (biogeographical regions) and pan-tropical scale at three spatial resolutions (1.0, 0.25 and 0.0625 ha) using Poisson regression. Results: The results showed a weak structure–richness relationship at the local scale. At the regional scale (within a biogeographical region) a stronger relationship between canopy structure and tree species richness across different tropical forest types was found, for example across Central Africa and in South America [R2 ranging from.44–.56, root mean squared difference as a percentage of the mean (RMSD%) ranging between 23–61%]. Modelling the relationship pan-tropically, across four continents, 39% of the variation in tree species richness could be explained with canopy structure alone (R2 =.39 and RMSD% = 43%, 0.25-ha resolution). Main conclusions: Our results may serve as a basis for the future development of a set of structure–richness models to map high resolution tree species richness using vertical canopy structure information from the Global Ecosystem Dynamics Investigation (GEDI). The value of this effort would be enhanced by access to a larger set of field reference data for all tropical regions. Future research could also support the use of GEDI data in frameworks using environmental and spectral information for modelling tree species richness across the tropics.

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评估全波形激光雷达绘制泛热带树种丰富度的潜力

© 2020 John Wiley & Sons Ltd 目标：绘制热带树种丰富度对有效保护和生物多样性管理具有重要意义。在这项研究中，我们通过将垂直冠层结构的测量值（作为垂直生态位空间占用的代理）与树种丰富度相关联，评估了全波形激光雷达数据在绘制热带树种丰富度方面的潜力。地点：热带地区。时间段：现在。研究的主要分类群：树木。方法：首先，我们使用（模拟）大足迹全波形激光雷达数据（直径 22 m）评估了 15 个研究地点的垂直冠层结构的特征，并将这些发现与原位树种信息相关联。然后，我们在当地（25-50 公顷地块内）开发了结构丰富度模型，使用泊松回归在三个空间分辨率（1.0、0.25 和 0.0625 公顷）下的区域（生物地理区域）和泛热带尺度。结果：结果显示局部尺度上的结构-丰富度关系较弱。在区域尺度（在一个生物地理区域内），发现不同热带森林类型的冠层结构和树种丰富度之间的关系更强，例如在中非和南美洲 [R2 范围为 0.44-0.56，均方根差异作为平均值的百分比 (RMSD%)，范围在 23-61% 之间]。模拟泛热带的关系，跨越四大洲，树种丰富度的 39% 变化可以单独用冠层结构来解释（R2 =.39 和 RMSD% = 43%，0.25 公顷分辨率）。主要结论：我们的结果可作为未来开发一组结构丰富度模型的基础，以使用来自全球生态系统动态调查 (GEDI) 的垂直冠层结构信息绘制高分辨率树种丰富度。通过访问所有热带地区的更多实地参考数据，可以提高这项工作的价值。未来的研究还可以支持在框架中使用 GEDI 数据，使用环境和光谱信息来模拟热带地区的树种丰富度。