Modified Feddes type stress reduction function for modeling root water uptake: Accounting for limited aeration and low water potential
Modified Feddes type stress reduction function for modeling root water uptake: Accounting for limited aeration and low water potential
复制标题
用于模拟根部吸水量的改良 Feddes 型应力降低函数：考虑有限的通气和低水势
DOI：
10.1016/j.agwat.2017.02.010
复制
发表时间：
2017
影响因子：
6.7
通讯作者：
W. Durner
中科院分区：
文献类型：
--
作者：
Peters;S. Iden;W. Durner
用理查兹方程模拟土壤-植物-大气连续体中的水流需要一个描述植物根系吸收水分的汇项模型。尽管近年来基于过程的植物根系吸水模型和植被地上部分水流模型的开发取得了进展，但有效的根系吸水模型应用广泛，并且需要大规模应用。模拟根系水分吸收包括三个步骤，(i)确定潜在吸收量的空间分布，（ii）由于各种压力源而减少吸收量，以及（iii）在部分模拟域中增强吸收量以描述补偿。本文讨论了常用的黄杨根系水分吸收模型在概念上的缺陷，并提出了一种简单而有效的模型改进方法。改进后的模型将湿土中的水应力参数化，并将其简化为空气含量的函数，而由低土壤水势引起的水应力则由Feddes的原始方法描述。改进的模型在物理上比Feddes的模型更一致，因为湿土的吸水性受到曝气的限制，而曝气是含水量的函数。建议的修改特别适用于非均质土壤的模拟，因为应力参数在整个模拟域中是唯一定义的，而不考虑土壤质地。均质和随机非均质土壤的水流和根系水分吸收数值模拟表明了新模型对根系水分吸收和实际蒸腾的影响。对于均匀的细质土壤，预测的根系吸水率从未达到其潜在速率。在随机非均质土壤中，预测水分吸收在细区和粗区交界处更为明显，这对植物生长、养分吸收和耗竭具有潜在的影响。
Modeling water flow in the soil–plant–atmosphere continuum with the Richards equation requires a model for the sink term describing water uptake by plant roots. Despite recent progress in developing process-based models of water uptake by plant roots and water flow in above-ground parts of vegetation, effective models of root water uptake are widely applied and necessary for large-scale applications. Modeling root water uptake consists of three steps, (i) specification of the spatial distribution of potential uptake, (ii) reduction of uptake due to various stress sources, and (iii) enhancement of uptake in part of the simulation domain to describe compensation. We discuss the conceptual shortcomings of the frequently used root water uptake model of Feddes and suggest a simple but effective improvement of the model. The improved model parametrizes water stress in wet soil by a reduction scheme which is formulated as function of air content whereas water stress due to low soil water potential is described by the original approach of Feddes. The improved model is physically more consistent than Feddes’ model because water uptake in wet soil is limited by aeration which is a function of water content. The suggested modification is particularly relevant for simulations in heterogeneous soils, because stress parameters are uniquely defined for the entire simulation domain, irrespective of soil texture. Numerical simulations of water flow and root water uptake in homogeneous and stochastic heterogeneous soils illustrate the effect of the new model on root water uptake and actual transpiration. For homogeneous fine-textured soils, predicted root water uptake never achieves its potential rate. In stochastic heterogeneous soil, predicted water uptake is more pronounced at the interfaces between fine and coarse regions which has potential implications for plant growth, nutrient uptake and depletion.
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影响因子：
2.8
作者：
Q. Jong Van Lier;J. Dam;Angelica Durigon;Marcos A. Santos;K. Metselaar
通讯作者：
Q. Jong Van Lier;J. Dam;Angelica Durigon;Marcos A. Santos;K. Metselaar
影响因子：
6.4
作者：
A. Peters;S. Iden;W. Durner
通讯作者：
A. Peters;S. Iden;W. Durner
影响因子：
5.4
作者：
L. Luckner;M. Genuchten;D. R. Nielsen
通讯作者：
L. Luckner;M. Genuchten;D. R. Nielsen
土壤异质性和植被类型对田间年水平衡的综合影响
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
S. Schlüter;H. Vogel;O. Ippisch;J. Vanderborght
通讯作者：
J. Vanderborght
影响因子：
5.4
作者：
A. Peters
通讯作者：
A. Peters