Sensitivity of South American tropical forests to an extreme climate anomaly
Sensitivity of South American tropical forests to an extreme climate anomaly
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DOI：
10.1038/s41558-023-01776-4
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发表时间：
2023-09-04
影响因子：
30.7
通讯作者：
Phillips, Oliver L.
中科院分区：
文献类型：
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作者：
Bennett, Amy C.;Rodrigues de Sousa, Thaiane;Phillips, Oliver L.
众所周知，热带森林的碳汇对干旱很敏感，但目前尚不清楚哪些森林最容易受到极端事件的影响。基线条件更热、更干燥的森林可能受到事先适应的保护，或者更容易受到伤害，因为它们更接近生理极限。在这里，我们报告说，南美洲气候干燥的森林受2015-2016年厄尔尼诺现象的影响最大，表明更容易受到极端温度和干旱的影响。对南美洲热带123个森林样地逐树的长期地面测量结果表明，在这一事件期间，生物量碳汇停止，碳平衡接近于零（-0.02 & PLUSMN； 0.37 Mg C ha-1 /年）。然而，整体而言，完整的南美洲热带森林对2015-2016年极端厄尔尼诺现象的敏感性并不高于之前不那么强烈的事件，只要受到保护，它们仍然是抵御气候变化的关键屏障。作者分析了树木对南美洲极端高温和干旱事件的反应，以了解长期的气候抗性。尽管干旱气候下的森林对气候变化的敏感性并不比以前较小的气候事件更强，但它们受到的影响最大，因此容易受到极端气候的影响。
The tropical forest carbon sink is known to be drought sensitive, but it is unclear which forests are the most vulnerable to extreme events. Forests with hotter and drier baseline conditions may be protected by prior adaptation, or more vulnerable because they operate closer to physiological limits. Here we report that forests in drier South American climates experienced the greatest impacts of the 2015-2016 El Nino, indicating greater vulnerability to extreme temperatures and drought. The long-term, ground-measured tree-by-tree responses of 123 forest plots across tropical South America show that the biomass carbon sink ceased during the event with carbon balance becoming indistinguishable from zero (-0.02 & PLUSMN; 0.37 Mg C ha-1 per year). However, intact tropical South American forests overall were no more sensitive to the extreme 2015-2016 El Nino than to previous less intense events, remaining a key defence against climate change as long as they are protected.The authors analyse tree responses to an extreme heat and drought event across South America to understand long-term climate resistance. While no more sensitive to this than previous lesser events, forests in drier climates showed the greatest impacts and thus vulnerability to climate extremes.