Thermal safety margins of plant leaves across biomes under a heatwave.
Thermal safety margins of plant leaves across biomes under a heatwave.
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热浪下生物群落植物叶子的热安全裕度。
DOI：
10.1016/j.scitotenv.2021.150416
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Kitudom N
中科院分区：
文献类型：
--
作者：
Kitudom N
气候变化对森林生态系统的影响很大，尤其是随着热浪频率的增加。由体温与耐热阈值之差计算的热安全裕度(TSM)可用于预测生物的热安全性。它已被广泛用于动物，而很少有关于植物的报道。此外，以往的研究大多只用热容忍度来评价热安全性，或者用热容忍度和气温(Ta)来计算TSM。然而，叶温(TL)是植物叶片的真实“体温”。Tl与Ta的解耦可能会在TSM中引入较大的误差。在这里，我们研究了热带和温带生物群中四种森林中主要冠层植物的光系统II(PSII的热耐性-最大热释光)在热波过程中的TSM，并分别比较了TL(TSM.Tl)和Ta(TSM.Ta)计算的TSm。此外，还对与温度有关的叶片性状进行了研究。结果表明，TSM和TSM均有不同程度的抑制作用。热带雨林和热带雨林Ta由冷林向热林递减。TSM.Tl与最高叶温(Tlmax)高度相关，而与不同生态区的耐热性呈相反趋势。因此，可以用Tlmax代替耐热性来评价TSM。在随机森林模型中，Ta(Tamax)、Tlmax和叶片性状的最大值可解释耐热性变异的68%，其中Tamax和Tlmax可解释62%。TSM.Ta不能区分共存物种之间的热安全差异。TSM对TSM的高估，Ta从热带森林到温带森林逐渐增加，并且在生物群内随着TL的增加而增加。因此，不建议在寒冷的森林中使用TSM.Ta。本研究丰富了不同生态区的光合作用TSM数据集，提出了用Tlmax估算叶片TSM的方法，并强调了热浪期间干热森林的风险。
Climate change has great impacts on forest ecosystems, especially with the increasing frequency of heatwaves. Thermal safety margin (TSM) calculated by the difference between body temperature and thermotolerance threshold is useful to predict thermal safety of organisms. It has been widely used for animals, whereas has rarely been reported for plants. Besides, most of the previous studies used only thermotolerance to estimate thermal safety or used thermotolerance and air temperature (Ta) to calculate TSM. However, leaf temperature (Tl) is the real “body” temperature of plant leaves. Tl decoupling from Ta might induce large error in TSM. Here, we investigated TSM of photosystem II (thermotolerance of PSII – the maximum Tl) of dominant canopy plants in four forests from tropical to temperate biomes during a heatwave, and compared the TSMs calculated by Tl (TSM.Tl) and Ta (TSM.Ta) respectively. Also, thermal related leaf traits were investigated. The results showed that both TSM. Tl and TSM.Ta decreased from the cool forests to the hot forests. TSM.Tl was highly correlated with the maximum leaf temperature (Tlmax), while had an opposite trend with thermotolerance across biomes. Thus, Tlmax instead of thermotolerance can be used to evaluate TSM. The maximum Ta (Tamax), Tlmax and leaf traits explained 68% of the variance of thermotolerance in a random forest model, where Tamax and Tlmax explained 62%. TSM.Ta could not distinguish thermal safety differences between co-occurring species. The overestimation of TSM by TSM.Ta increased from the tropical to the temperate forest, and increased with Tl within biome. Therefore, it is not recommended to use TSM.Ta in cold forests. The present study enriches the dataset of photosynthetic TSMs across biomes, proposes using Tlmax to estimate TSMs of leaves, and highlights the risk of hot dry forest during heatwaves.
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影响因子：
5.2
作者：
Cook, Alicia M.;Berry, Neil;Leigh, Andrea
通讯作者：
Leigh, Andrea
沙漠和山地植物光合热耐受性和对短期温度胁迫的恢复：比较研究
DOI：
--
发表时间：
2014
期刊：
影响因子：
--
作者：
David W. Gallagher
通讯作者：
David W. Gallagher
影响因子：
5.2
作者：
Perez, Timothy M.;Feeley, Kenneth J.
通讯作者：
Feeley, Kenneth J.
影响因子：
3
作者：
Heinrich Krause, G.;Winter, Klaus;Virgo, Aurelio
通讯作者：
Virgo, Aurelio
植物生理生态学
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
C. Vázquez
通讯作者：
C. Vázquez