Chen Ya-Jun, Choat Brendan, Sterck Frank, Maenpuen Phisamai, Katabuchi Masatoshi, Zhang Shu-Bin, Tomlinson Kyle W, Oliveira Rafael S, Zhang Yong-Jiang, Shen Jing-Xian, Cao Kun-Fang, Jansen Steven
CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China.
Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Yunnan, China.
Ecol Lett. 2021 Nov;24(11):2350-2363. doi: 10.1111/ele.13856. Epub 2021 Aug 18.
Hydraulic failure caused by severe drought contributes to aboveground dieback and whole-plant death. The extent to which dieback or whole-plant death can be predicted by plant hydraulic traits has rarely been tested among species with different leaf habits and/or growth forms. We investigated 19 hydraulic traits in 40 woody species in a tropical savanna and their potential correlations with drought response during an extreme drought event during the El Niño-Southern Oscillation in 2015. Plant hydraulic trait variation was partitioned substantially by leaf habit but not growth form along a trade-off axis between traits that support drought tolerance versus avoidance. Semi-deciduous species and shrubs had the highest branch dieback and top-kill (complete aboveground death) among the leaf habits or growth forms. Dieback and top-kill were well explained by combining hydraulic traits with leaf habit and growth form, suggesting integrating life history traits with hydraulic traits will yield better predictions.
严重干旱导致的水力衰竭会致使地上部分枯死和整株植物死亡。在具有不同叶习性和/或生长形式的物种中，很少有人测试过植物水力性状对枯死或整株植物死亡的预测程度。我们调查了热带稀树草原中40种木本植物的19种水力性状，以及在2015年厄尔尼诺-南方涛动极端干旱事件期间它们与干旱响应的潜在相关性。沿着支持耐旱性与避旱性的性状之间的权衡轴，植物水力性状的变异在很大程度上由叶习性而非生长形式划分。在叶习性或生长形式中，半落叶物种和灌木的枝条枯死和顶部死亡（地上部分完全死亡）比例最高。结合水力性状、叶习性和生长形式能很好地解释枯死和顶部死亡现象，这表明将生活史性状与水力性状相结合将能做出更好的预测。
