Simulation of stand transpiration based on a xylem water flow model for individual trees
Simulation of stand transpiration based on a xylem water flow model for individual trees
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基于单株木质部水流模型的林分蒸腾模拟
DOI：
10.1016/j.agrformet.2013.08.002
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发表时间：
2013
影响因子：
6.2
通讯作者：
Priesack E.
中科院分区：
文献类型：
--
作者：
Hentschel R;Bittner S;Janott;Biernath C;Holst J;Ferrio J.P;Gessler A;Priesack E.
定量森林与大气之间的水分交换对于预测未来的生长条件和规划造林措施具有重要意义。在本研究中，我们解决（一）在树水平的液流估计的不确定性和（ii）林分蒸腾模拟的性能。陆地激光扫描图像（TLS）的一个成熟的山毛榉立场（水青冈sylvaticaL。）在这里使用的单树木质部水流模型（XWF）中，98棵山毛榉树由具有明确方向和大小的连接圆柱体的3D图形表示。山毛榉的具体水力参数和物理特性的个别树木确定的生理反应的树模型的环境conditions.TheXWF模拟进行没有进一步的校准液流测量。模拟可靠地匹配来自液流密度测量的液流估计。密度测量强烈依赖于个人边材面积估计和径向液流密度梯度与木质部深度的表征。虽然所观察到的纯山毛榉立场是均匀的年龄，我们观察到的树液流率之间的个别树木的高变异性。林分蒸腾速率的模拟结果与林分水平根系吸水模型（RWUmodel）的模拟结果进行了比较。使用RWU模型的结果在一个高35%的模拟季节性林分蒸腾相对于theXWF模型。这些研究结果表明，在估计林分用水量的个体树的尺寸和林分异质性评估的重要性。由于物种特定的模型参数化和preciseTLS为基础的立场表征，theXWF模型适用于各种网站和树种，是一个很有前途的工具，用于预测可能的供水限制的纯林和混交林的立场。
Quantifying the water exchange between a forest stand and the atmosphere is of major interest for the prediction of future growth conditions and the planning of silvicultural treatments. In the present study, we address (i) the uncertainties of sap flow estimations at the tree level and (ii) the performance of the simulation of stand transpiration. Terrestrial laser scan images (TLS) of a mature beech stand (Fagus sylvaticaL.) in Southwestern Germany serve as input data for a representation of the aboveground tree architecture of the study stand. In the single-tree xylem water flow model (XWF) used here, 98 beech trees are represented by 3D graphs of connected cylinders with explicit orientation and size. Beech-specific hydraulic parameters and physical properties of individual trees determine the physiological response of the tree model to environmental conditions.TheXWFsimulations are performed without further calibration to sap flow measurements. The simulations reliably match up with sap flow estimates derived from sap flow density measurements. The density measurements strongly depend on individual sapwood area estimates and the characterization of radial sap flow density gradients with xylem depth. Although the observed pure beech stand is even-aged, we observe a high variability in sap flow rates among the individual trees. Simulations of the individual sap flow rates show a corresponding variability due to the distribution of the crown projection area in the canopy and the different proportions of sapwood area.Stand transpiration is obtained by taking the sum of 98 single-tree simulations and the corresponding sap flow estimations, which are then compared with the stand-level root water uptake model (RWUmodel) simulation. Using theRWUmodel results in a 35% higher simulation of seasonal stand transpiration relative to theXWFmodel. These findings demonstrate the importance of individual tree dimensions and stand heterogeneity assessments in estimating stand water use. As a consequence of species-specific model parameterization and preciseTLS-based stand characterization, theXWFmodel is applicable to various sites and tree species and is a promising tool for predicting the possible water supply limitations of pure and mixed forest stands.
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解决欧洲森林管理和环境挑战的建模趋势：简介
影响因子：
0.7
作者：
H. Bugmann;M. Palahí;H. Bontemps;M. Tomé
通讯作者：
M. Tomé
气候胁迫下植物中的水输送：空化对植物中水状态的影响
DOI：
10.1017/cbo9780511753305.004
发表时间：
1993
期刊：
Trees
影响因子：
--
作者：
J. Oertli
通讯作者：
J. Oertli
影响因子：
2
作者：
Fruh;Kurth
通讯作者：
Kurth
单棵树中水流的动态模型：模型必须考虑水力建筑的证据。
影响因子：
4
作者：
Melvin T. Tyree
通讯作者：
Melvin T. Tyree
影响因子：
4
作者：
Gebauer, Tobias;Horna, Viviana;Leuschner, Christoph
通讯作者：
Leuschner, Christoph