An easily implemented agro-hydrological procedure with dynamic root simulation for water transfer in the crop–soil system: validation and application
Yang, D. (Dejun), Zhang, Tuqiao, Zhang, Kefeng, Greenwood, Duncan J. , Hammond, John P. and White, Philip J.. (2009) An easily implemented agro-hydrological procedure with dynamic root simulation for water transfer in the crop–soil system: validation and application. Journal of Hydrology, Vol.370 (No.1-4). pp. 177-190. ISSN 0022-1694
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Official URL: http://dx.doi.org/10.1016/j.jhydrol.2009.03.005 ...
Models for water transfer in the crop–soil system are key components of agro-hydrological models for irrigation, fertilizer and pesticide practices. Many of the hydrological models for water transfer in the crop–soil system are either too approximate due to oversimplified algorithms or employ complex numerical schemes. In this paper we developed a simple and sufficiently accurate algorithm which can be easily adopted in agro-hydrological models for the simulation of water dynamics. We used a dual crop coefficient approach proposed by the FAO for estimating potential evaporation and transpiration, and a dynamic model for calculating relative root length distribution on a daily basis. In a small time step of 0.001 d, we implemented algorithms separately for actual evaporation, root water uptake and soil water content redistribution by decoupling these processes. The Richards equation describing soil water movement was solved using an integration strategy over the soil layers instead of complex numerical schemes. This drastically simplified the procedures of modeling soil water and led to much shorter computer codes. The validity of the proposed model was tested against data from field experiments on two contrasting soils cropped with wheat. Good agreement was achieved between measurement and simulation of soil water content in various depths collected at intervals during crop growth. This indicates that the model is satisfactory in simulating water transfer in the crop–soil system, and therefore can reliably be adopted in agro-hydrological models. Finally we demonstrated how the developed model could be used to study the effect of changes in the environment such as lowering the groundwater table caused by the construction of a motorway on crop transpiration.
|Item Type:||Journal Article|
|Subjects:||S Agriculture > SB Plant culture|
|Divisions:||Faculty of Science > Life Sciences (2010- ) > Warwick HRI (2004-2010)|
|Library of Congress Subject Headings (LCSH):||Hydrologic models, Crops -- Water requirements, Crops and soils, Agriculture -- Data processing, Crops and water|
|Journal or Publication Title:||Journal of Hydrology|
|Official Date:||30 May 2009|
|Page Range:||pp. 177-190|
|Access rights to Published version:||Open Access|
|Funder:||Great Britain. Dept. for Environment, Food & Rural Affairs (DEFRA)|
|Grant number:||HH3507SFV (DEFRA)|
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