Extraction of soil water by plants: development and validation of a model

Revista Brasileira de Ciência do Solo

Q. De Jong Van Lier²  P. L. Libardi¹ 

[1] ,Universidade Federal do Rio Grande do Sul Faculdade de Agronomia Departamento de SolosPorto Alegre RS

关键词: modelling;    soil water depletion;    soil water extraction;    modelagem;    esgotamento de água;    extração de água do solo;   

DOI  :  10.1590/S0100-06831997000400002

来源: SciELO

【 摘 要 】

A quantitative model of water movement within the immediate vicinity of an individual root is developed and results of an experiment to validate the model are presented. The model is based on the assumption that the amount of water transpired by a plant in a certain period is replaced by an equal volume entering its root system during the same time. The model is based on the Darcy-Buckingham equation to calculate the soil water matric potential at any distance from a plant root as a function of parameters related to crop, soil and atmospheric conditions. The model output is compared against measurements of soil water depletion by rice roots monitored using γ-beam attenuation in a greenhouse of the Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo(ESALQ/USP) in Piracicaba, State of São Paulo, Brazil, in 1993. The experimental results are in agreement with the output from the model. Model simulations show that a single plant root is able to withdraw water from more than 0.1 m away within a few days. We therefore can assume that root distribution is a less important factor for soil water extraction efficiency.

【 授权许可】

CC BY   
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