Divergent forest sensitivity to repeated extreme droughts
Divergent forest sensitivity to repeated extreme droughts
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DOI：
10.1038/s41558-020-00919-1
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发表时间：
2020-09-28
影响因子：
30.7
通讯作者：
Shaw, John
中科院分区：
文献类型：
--
作者：
Anderegg, William R. L.;Trugman, Anna T.;Shaw, John
气候变化导致的干旱频率和严重程度的增加可能损害森林生态系统和陆地碳汇（1-3）。虽然单一干旱对森林的影响已得到广泛研究（4-6），但了解森林是否适应或更容易受到连续干旱的影响仍然是一个未知数，这对预测未来的森林健康至关重要。我们结合联合收割机树木生长，树木死亡率和生态系统含水量的跨生物群系数据集，以量化从1900年到2018年从单个树木到地球仪的多种干旱的影响。我们发现，随后的干旱一般有一个更有害的影响比最初的干旱，但这种影响有很大的不同的进化枝和生态系统，裸子植物和针叶树为主的生态系统往往表现出更大的脆弱性，多次干旱。多种干旱对各分支和生物群落的不同影响表明，干旱频率的变化可能对各生态系统产生根本不同的生态和碳循环后果。
Climate change-driven increases in drought frequency and severity could compromise forest ecosystems and the terrestrial carbon sink(1-3). While the impacts of single droughts on forests have been widely studied(4-6), understanding whether forests acclimate to or become more vulnerable to sequential droughts remains largely unknown and is crucial for predicting future forest health. We combine cross-biome datasets of tree growth, tree mortality and ecosystem water content to quantify the effects of multiple droughts at a range of scales from individual trees to the globe from 1900 to 2018. We find that subsequent droughts generally have a more deleterious impact than initial droughts, but this effect differs enormously by clade and ecosystem, with gymnosperms and conifer-dominated ecosystems more often exhibiting increased vulnerability to multiple droughts. The differential impacts of multiple droughts across clades and biomes indicate that drought frequency changes may have fundamentally different ecological and carbon-cycle consequences across ecosystems.