DOI: 10.5194/hess-21-6519-2017
Scopus记录号: 2-s2.0-85039160432
论文题名: Water movement through plant roots - Exact solutions of the water flow equation in roots with linear or exponential piecewise hydraulic properties
作者: Meunier F ; , Couvreur V ; , Draye X ; , Zarebanadkouki M ; , Vanderborght J ; , Javaux M
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2017
卷: 21, 期: 12 起始页码: 6519
结束页码: 6540
语种: 英语
Scopus关键词: Axial flow
; Carbon
; Hydraulics
; Plants (botany)
; Conductance measurement
; Environment management
; Exponential variation
; Hydraulic parameters
; Hydraulic properties
; Influencing parameters
; Macroscopic parameters
; Xylem water potential
; Flow of water
; agricultural modeling
; ecohydrology
; genotype-environment interaction
; hydraulic property
; morphology
; optimization
; root
; water flow
; water uptake
; xylem
; Zea mays
英文摘要: In 1978, Landsberg and Fowkes presented a solution of the water flow equation inside a root with uniform hydraulic properties. These properties are root radial conductivity and axial conductance, which control, respectively, the radial water flow between the root surface and xylem and the axial flow within the xylem. From the solution for the xylem water potential, functions that describe the radial and axial flow along the root axis were derived. These solutions can also be used to derive root macroscopic parameters that are potential input parameters of hydrological and crop models. In this paper, novel analytical solutions of the water flow equation are developed for roots whose hydraulic properties vary along their axis, which is the case for most plants. We derived solutions for single roots with linear or exponential variations of hydraulic properties with distance to root tip. These solutions were subsequently combined to construct single roots with complex hydraulic property profiles. The analytical solutions allow one to verify numerical solutions and to get a generalization of the hydric behaviour with the main influencing parameters of the solutions. The resulting flow distributions in heterogeneous roots differed from those in uniform roots and simulations led to more regular, less abrupt variations of xylem suction or radial flux along root axes. The model could successfully be applied to maize effective root conductance measurements to derive radial and axial hydraulic properties. We also show that very contrasted root water uptake patterns arise when using either uniform or heterogeneous root hydraulic properties in a soil-root model. The optimal root radius that maximizes water uptake under a carbon cost constraint was also studied. The optimal radius was shown to be highly dependent on the root hydraulic properties and close to observed properties in maize roots. We finally used the obtained functions for evaluating the impact of root maturation versus root growth on water uptake. Very diverse uptake strategies arise from the analysis. These solutions open new avenues to investigate for optimal genotype-environment-management interactions by optimization, for example, of plant-scale macroscopic hydraulic parameters used in ecohydrogolocial models. © 2017 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78956
Appears in Collections: 气候变化事实与影响
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作者单位: Earth and Life Institute - Environment, Université Catholique de Louvain, Louvain-la-Neuve, Belgium; Earth and Life Institute - Agronomy, Université Catholique de Louvain, Louvain-la-Neuve, Belgium; Division of Soil Physics, University of Bayreuth, Germany; Forschungszentrum Juelich GmbH, Agrosphere (IBG-3), Juelich, Germany; Division of Soil and Water Management, KU Leuven, Leuven, Belgium
Recommended Citation:
Meunier F,, Couvreur V,, Draye X,et al. Water movement through plant roots - Exact solutions of the water flow equation in roots with linear or exponential piecewise hydraulic properties[J]. Hydrology and Earth System Sciences,2017-01-01,21(12)