Evapotranspiration regulates leaf temperature and respiration in dryland vegetation
Evapotranspiration regulates leaf temperature and respiration in dryland vegetation
复制标题
蒸散量调节旱地植被的叶温和呼吸
DOI：
10.1016/j.agrformet.2023.109560
复制
发表时间：
2023
影响因子：
6.2
通讯作者：
Singer, Michael Bliss
中科院分区：
文献类型：
--
作者：
Kibler, Christopher L.;Trugman, Anna T.;Roberts, Dar A.;Still, Christopher J.;Scott, Russell L.;Caylor, Kelly K.;Stella, John C.;Singer, Michael Bliss
蒸散调节叶表面的能流分配，从而调节叶温度。然而，蒸散量和叶温之间的机械关系仍然缺乏约束。在这项研究中，我们提出了一种新的机械模型来预测叶温作为蒸发分数的线性化函数。该模型进行了验证，使用安装在两个通量塔在美国亚利桑那州，测量冠层ofProsopis velutina与对比水的可用性的红外辐射计的测量。观测和模型预测表明，当潜热通量消耗了所有入射在叶片表面的能量时，叶片温度与空气温度平衡。当有能量净输入叶组织时，叶温度超过空气温度。通量塔的观测结果表明，蒸发冷却降低冠层叶片温度约1 -5 °C，这取决于水的可用性。蒸发冷却也提高了净碳吸收减少叶片呼吸由ca。15%，在中间的生长季节。蒸散对叶温的调节及其对净碳吸收的影响是植物水分和碳循环之间的重要联系，但在文献中很少受到关注。本文提出的模型提供了一个量化叶片蒸发冷却和研究其对植物生理功能影响的机制框架。
Evapotranspiration regulates energy flux partitioning at the leaf surface, which in turn regulates leaf temperature. However, the mechanistic relationship between evapotranspiration and leaf temperature remains poorly constrained. In this study, we present a novel mechanistic model to predict leaf temperature as a linearized function of the evaporative fraction. The model is validated using measurements from infrared radiometers mounted on two flux towers in Arizona, USA, which measure canopies ofProsopis velutinawith contrasting water availability. Both the observations and model predictions reveal that leaf temperature equilibrates with air temperature when latent heat flux consumes all of the energy incident on the leaf surface. Leaf temperature exceeds air temperature when there is a net input of energy into the leaf tissue. The flux tower observations revealed that evaporative cooling reduced canopy leaf temperature byca.1–5 °C, depending on water availability. Evaporative cooling also enhanced net carbon uptake by reducing leaf respiration byca.15% in the middle of the growing season. The regulation of leaf temperature by evapotranspiration and the resulting impact on net carbon uptake represents an important link between plant water and carbon cycles that has received little attention in literature. The model presented here provides a mechanistic framework to quantify leaf evaporative cooling and examine its impacts on plant physiological function.
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DOI：
10.1073/pnas.2205682119
发表时间：
2022-09-20
影响因子：
11.1
作者：
通讯作者：
--
DOI：
--
发表时间：
2003
期刊：
影响因子：
--
作者：
Rongqian Yang;M. Friedl
通讯作者：
M. Friedl
影响因子：
3.2
作者：
Mayes, Marc;Caylor, Kelly K.;Nagler, Pamela
通讯作者：
Nagler, Pamela
来自 FLUXNET 的生态系统蒸腾
DOI：
--
发表时间：
2020
期刊：
影响因子：
--
作者：
Jacob A. Nelson
通讯作者：
Jacob A. Nelson
亚利桑那州东南部植被对气候和地质控制对水资源可用性的响应
影响因子：
6.7
作者：
Sabathier, Romy;Singer, Michael Bliss;Stella, John C;Roberts, Dar A;Caylor, Kelly K
通讯作者：
Caylor, Kelly K