The frequency and intensity of droughts have increased over the decades, leading to increased forest decline. The response of forest to drought can be evaluated by both its sensitivity to drought (resistance) and its post-drought recovery rate (resilience). However, it remains uncertain how drought resistance and resilience of forests change over time under climate change. We assessed the spatiotemporal dynamics of forest resistance and resilience to drought over the past century (1901–2015) with global tree ring data records from 2,935 sites, in conjunction with plant trait data. We found that gymnosperms and angiosperms showed different spatial patterns of drought resistance and resilience, driven by variations in eco-physiological traits. Resistance and resilience also varied with drought seasonal timing. Surprisingly, we found that the trade-off between resistance and resilience for gymnosperms, previously reported only spatially, also occurred at the temporal scale. In particular, drought resilience markedly increased, but resistance decreased, for gymnosperms between 1950–1969 and 1990–2009, indicating that previous model simulations assuming invariant resistance may have underestimated the impacts of drought on gymnosperm-dominated forests under future climate change.

在过去的几十年中，干旱的频率和强度有所增加，导致森林退化的加剧。森林对干旱的反应可以通过其对干旱的敏感性（抗性）和其干旱后的恢复率（抗逆性）来评估。然而，在气候变化下，抗旱性和森林的复原力如何随时间变化仍然不确定。我们使用来自2935个站点的全球年轮数据记录以及植物性状数据，评估了过去一个世纪（1901-2015年）的森林抗旱性和抗旱性的时空动态。我们发现裸子植物和被子植物在生态生理特征变化的驱动下表现出不同的抗旱性和恢复力空间格局。抵抗力和恢复力也随干旱季节时机而变化。出奇，我们发现，以前仅在空间上报道的裸子植物的抗性和弹性之间的权衡也发生在时间尺度上。特别是，裸子植物在1950–1969年至1990–2009年之间的干旱复原力显着提高，而抗性下降，这表明以前的模型模拟假设不变的抗性可能低估了干旱对未来气候变化下裸子植物为主的森林的影响。