Unraveling the hydrodynamics of split root water uptake experiments using CT scanned root architectures and three dimensional flow simulations.
Unraveling the hydrodynamics of split root water uptake experiments using CT scanned root architectures and three dimensional flow simulations.
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DOI：
10.3389/fpls.2015.00370
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发表时间：
2015
影响因子：
5.6
通讯作者：
Vetterlein D
中科院分区：
文献类型：
--
作者：
Koebernick N;Huber K;Kerkhofs E;Vanderborght J;Javaux M;Vereecken H;Vetterlein D
分根实验有可能解开根系和土壤中的水分运输，使根系吸水模式的调查。对实验数据的解释假设分裂土壤室之间的水流不会发生。研究根系吸水的另一种方法是通过结合土壤和根系水流的数值模拟，这取决于根系的参数化和描述。我们的目的是证明从结合分裂根实验与模拟出现的协同作用。我们展示了如何不断增长的根结构来自时间上重复的X射线CT扫描可以实现在数值土壤植物模型。蚕豆种植有和没有分裂层，并暴露于一个单一的干旱期，在此期间，植物和土壤水分状况进行了测量。利用CT扫描重建根系构型，并将其应用于R-SWMS（root-soil water movement and solute transport）模型中，模拟土壤和根系的三维水势以及不同深度根系的吸水情况。CT扫描显示，与没有分裂层相比，根的发育显著降低。这与蒸腾作用，气孔导度和新梢生长的减少相吻合。模拟黎明前的水势较低，在分裂层的存在。模拟结果表明，这与分层增加了土壤中垂直水流的阻力有关。实测和模拟的土壤水势之间的比较证明，分裂层并没有完全隔离，水分从较低的，湿润的车厢到干燥的上层车厢发生再分配，因此水分损失不等于从这些车厢的根吸水。尽管如此，层增加了垂直流的阻力，导致较低的模拟衣领水势，导致气孔导度和生长减少。
Split root experiments have the potential to disentangle water transport in roots and soil, enabling the investigation of the water uptake pattern of a root system. Interpretation of the experimental data assumes that water flow between the split soil compartments does not occur. Another approach to investigate root water uptake is by numerical simulations combining soil and root water flow depending on the parameterization and description of the root system. Our aim is to demonstrate the synergisms that emerge from combining split root experiments with simulations. We show how growing root architectures derived from temporally repeated X-ray CT scanning can be implemented in numerical soil-plant models. Faba beans were grown with and without split layers and exposed to a single drought period during which plant and soil water status were measured. Root architectures were reconstructed from CT scans and used in the model R-SWMS (root-soil water movement and solute transport) to simulate water potentials in soil and roots in 3D as well as water uptake by growing roots in different depths. CT scans revealed that root development was considerably lower with split layers compared to without. This coincided with a reduction of transpiration, stomatal conductance and shoot growth. Simulated predawn water potentials were lower in the presence of split layers. Simulations showed that this was related to an increased resistance to vertical water flow in the soil by the split layers. Comparison between measured and simulated soil water potentials proved that the split layers were not perfectly isolating and that redistribution of water from the lower, wetter compartments to the drier upper compartments took place, thus water losses were not equal to the root water uptake from those compartments. Still, the layers increased the resistance to vertical flow which resulted in lower simulated collar water potentials that led to reduced stomatal conductance and growth.
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影响因子：
2.7
作者：
Ackermann, J.;Vetterlein, D.;Jahn, R.
通讯作者：
Jahn, R.
影响因子：
2.8
作者：
Koebernick, Nicolai;Weller, Ulrich;Vetterlein, Doris
通讯作者：
Vetterlein, Doris
影响因子：
7.4
作者：
FRENSCH, J;STEUDLE, E
通讯作者：
STEUDLE, E
影响因子：
6.1
作者：
Kaestner, Anders;Schneebeli, Martin;Graf, Frank
通讯作者：
Graf, Frank
影响因子：
4.8
作者：
Clark, JS
通讯作者：
Clark, JS