The effects of short‐term extreme events on tree functioning and physiology are still rather elusive. European beech is one of the most sensitive species to late frost and water shortage. We investigated the intra‐annual C dynamics in stems under such conditions. Wood formation and stem CO₂ efflux were monitored in a Mediterranean beech forest for 3 years (2015–2017), including a late frost (2016) and a summer drought (2017). The late frost reduced radial growth and, consequently, the amount of carbon fixed in the stem biomass by 80%. Stem carbon dioxide efflux in 2016 was reduced by 25%, which can be attributed to the reduction of effluxes due to growth respiration. Counter to our expectations, we found no effects of the 2017 summer drought on radial growth and stem carbon efflux. The studied extreme weather events had various effects on tree growth. Even though late spring frost had a strong impact on beech radial growth in the current year, trees fully recovered in the following growing season, indicating high resilience of beech to this stressful event.

中文翻译：

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霜冻和干旱：极端天气事件对地中海山毛榉森林中茎碳动态的影响。

短期极端事件对树木功能和生理的影响仍然难以捉摸。欧洲山毛榉是对后期霜冻和缺水最敏感的物种之一。我们研究了在这种条件下茎中的年内碳动力学。木材形成和茎CO ₂在地中海山毛榉森林中监测了3年（2015-2017年）的外流，包括晚霜（2016年）和夏季干旱（2017年）。后期霜冻减少了径向生长，因此使茎生物量中固定的碳量减少了80％。2016年，干二氧化碳排放量减少了25％，这可以归因于生长呼吸导致的流出量减少。与我们的预期相反，我们发现2017年夏季干旱对径向生长和茎碳外排没有影响。所研究的极端天气事件对树木生长有多种影响。尽管今年春季晚霜对山毛榉径向生长有很大影响，但树木在随后的生长季节已完全恢复，这表明山毛榉对这种压力事件的抵抗力很高。