Extreme drought events have negative effects on forest diversity and functioning. At the species level, however, these effects are still unclear, as species vary in their response to drought through specific functional trait combinations. We used long‐term demographic records of 21,821 trees and extensive databases of traits to understand the responses of 338 tropical dry forests tree species to ENSO₂₀₁₅, the driest event in decades in Northern South America. Functional differences between species were related to the hydraulic safety‐efficiency trade‐off, but unexpectedly, dominant species were characterised by high investment in leaf and wood tissues regardless of their leaf phenological habit. Despite broad functional trait combinations, tree mortality was more widespread in the functional space than tree growth, where less adapted species showed more negative net biomass balances. Our results suggest that if dry conditions increase in this ecosystem, ecological functionality and biomass gain would be reduced.

中文翻译：

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不同的功能策略，但对热带干旱森林的极端干旱高度敏感

极端干旱事件对森林多样性和功能产生负面影响。然而，在物种水平上，这些影响仍不清楚，因为物种通过特定的功能性状组合对干旱的反应各不相同。我们使用 21,821 棵树的长期人口统计记录和广泛的特征数据库来了解 338 种热带干旱森林树种对 ENSO _{2015的响应}，南美洲北部几十年来最干旱的事件。物种之间的功能差异与水力安全效率权衡有关，但出乎意料的是，优势物种的特征是对叶片和木材组织的高投入，而不管其叶片物候习性如何。尽管有广泛的功能性状组合，但功能空间中的树木死亡率比树木生长更为普遍，其中适应性较差的物种表现出更多的负净生物量平衡。我们的研究结果表明，如果该生态系统中的干旱条件增加，生态功能和生物量增加将会减少。