Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing 400715, People's Republic of China.
Key Laboratory of Bio-Resource and Eco-Environment, Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, People's Republic of China.
Proc Biol Sci. 2024 Oct;291(2033):20241427. doi: 10.1098/rspb.2024.1427. Epub 2024 Oct 30.
The frequency and severity of drought events have increased with climate warming. This poses a significant threat to tree growth and survival worldwide. However, the underlying mechanism of tree growth responses to drought across diverse geographic regions and species remains inconclusive. Here, we used 2808 tree ring width chronologies of 32 species from 1951 to 2020 to examine the relationships between growth rates and resistance and recovery of trees in response to drought in the Northern Hemisphere. We found that trees with fast growth rates exhibited lower drought resistance but higher drought recovery compared to those with slow growth rates, which was further corroborated by the trade-off between resistance and recovery in response to variations in leaf photosynthetic traits. The difference in growth rates also well explained the large variability in the drought resistance and recovery for different geographic regions, as well as for species from different clades and successional stages. Our study provides a conclusive and uniform perspective that tree growth rate regulates drought resistance and recovery, shedding light on the diverse strategies employed by tree species in response to drought stress in the Northern Hemisphere.
随着气候变暖，干旱事件的频率和严重程度有所增加。这对全球范围内的树木生长和存活构成了重大威胁。然而，树木对干旱的生长响应在不同地理区域和物种之间的潜在机制仍未得到明确的结论。在这里，我们使用了 1951 年至 2020 年间来自 32 个物种的 2808 个树木年轮宽度年表，以检验北半球树木生长速率与对干旱的抵抗和恢复之间的关系。我们发现，与生长缓慢的树木相比，生长速度快的树木的抗旱能力较低，但抗旱恢复能力较高，这进一步证实了响应叶片光合特性变化时，在抵抗和恢复之间存在权衡关系。生长速率的差异也很好地解释了不同地理区域以及不同分支和演替阶段的物种之间抗旱能力和恢复能力的巨大变异性。我们的研究提供了一个明确而统一的观点，即树木生长速率调节抗旱能力和恢复能力，揭示了北半球树种应对干旱胁迫所采用的多样化策略。
