• Key message

The increase in climate variability is likely to generate an increased occurrence of both frost-induced and drought-induced damages on perennial plants. We examined how these stress factors can potentially interact and would subsequently affect the vulnerability to each other. Furthermore, we discussed how this vulnerability could be modulated by shifts in the annual phenological cycle.

Context

The edges of plant distribution are strongly affected by abiotic constraints: heat waves and drought at low latitude and elevation, cold and frost at high latitude and elevation. The increase in climate variability will enhance the probability of extreme events and thus the potential interaction of stress factors. The initial exposure to a first constraint may affect the vulnerability to a subsequent one.

Aims

Although three integrative physiological processes, namely water balance, carbon metabolism and the timing of phenological stages, have largely been studied in the response of trees to a single constraint, their interaction has rarely been investigated. How would the interaction of frost and drought constraints modulate the vulnerability to a subsequent constraint and how vulnerability to a given constraint and phenology interact?

Conclusion

We suggest that the interaction between frost and drought constraints should in the short-term influence water balance and, in the longer term, carbon metabolism, both consequently affecting further vulnerability. However, this vulnerability can be modulated by shifts in the annual phenological cycle. Significant gaps of knowledge are reported in a mechanistic framework. This framework can help to improve the current process-based models integrating the life history of the individual plant.

中文翻译：

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干旱与霜冻在树木生态生理中的相互作用：对风险时机的重新思考

• 关键信息

气候变异性的增加很可能导致多年生植物因霜冻和干旱引起的损害增加。我们研究了这些压力因素如何可能潜在地相互作用，并随后影响彼此之间的脆弱性。此外，我们讨论了如何通过年度物候周期的变化来调节此漏洞。

语境

植物分布的边缘受到非生物限制的强烈影响：低纬度和低海拔的热浪和干旱，高纬度和高海拔的寒冷和霜冻。气候变异性的增加将增加极端事件的可能性，从而增加压力因素的潜在相互作用。最初暴露于第一个约束可能会影响到后续约束的脆弱性。

目的

尽管已经在树木对单一约束的响应中对水的平衡，碳代谢和物候阶段的时间安排三个综合的生理过程进行了大量研究，但很少研究它们之间的相互作用。霜冻和干旱约束的相互作用将如何调节对后续约束的脆弱性，以及给定约束和物候学的脆弱性如何相互作用？

结论

我们建议，霜冻和干旱约束之间的相互作用应在短期内影响水平衡，从长远来看，应影响碳代谢，因此两者都影响了进一步的脆弱性。但是，可以通过年度物候周期的变化来调节此漏洞。在机制框架中报告了巨大的知识缺口。该框架可以帮助改进集成单个工厂寿命历史的当前基于过程的模型。