Extension of an Existing Model for Soil Water Evaporation and Redistribution under High Water Content Conditions
Extension of an Existing Model for Soil Water Evaporation and Redistribution under High Water Content Conditions
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DOI：
10.2136/sssaj2007.0325
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发表时间：
2009-05-01
影响因子：
2.9
通讯作者：
Suleiman, Ayman A.
中科院分区：
文献类型：
--
作者：
Ritchie, Joe T.;Porter, Cheryl H.;Suleiman, Ayman A.
大多数作物、水文和水质模型都需要模拟土壤表面的蒸发。里奇（J.T. Ritchie）在1972年提出的模型为估算土壤蒸发提供了有效的算法，但它没有计算蒸发引起的土壤水分再分布。Suleiman和里奇在2003年提出的基于扩散理论的物理模型为土壤水分再分布和土壤蒸发提供了有效的算法。然而，该模型仅适用于第二阶段干燥时，土壤在整个剖面被模拟低于排水上限（θ（DUL）），并没有更多的排水发生由于重力。本文将苏莱曼-里奇模型推广到土壤含水量高于θ（DUL）的情况，其中土壤蒸发速率通常高于第二阶段干燥。新的算法开发了这些潮湿的条件下，土壤深度和近地表土壤的湿度的函数。新的模型参数进行了校准，在实验室土柱研究中测得的数据。最后将该模型集成到农业技术转移种植系统模型决策支持系统DSSAT-CSM中。模拟土壤蒸发速率和土壤水分含量使用苏莱曼-里奇模型与开发的扩展和以前的DSSAT土壤蒸发模型进行了比较和评价与土壤水分含量在几个干燥周期的部分3年在中北部佛罗里达的实地测量。该模型计算的土壤含水量与实测的近地表土壤含水量吻合较好，且比DSSAT土壤蒸发模型的估算精度更高，尤其是对5cm表层的估算精度更高。
Most crop, hydrology, and water quality models require the simulation of evaporation from the soil surface. A model developed by J.T Ritchie in 1972 provides useful algorithms for estimating soil evaporation, but it does not calculate the soil water redistribution resulting from evaporation. A physically-based model using diffusion theory, described previously by Suleiman and Ritchie in 2003, provides efficient algorithms for soil water redistribution and soil evaporation. However, the model is appropriate only for second stage drying when the soil in the entire profile being simulated is below the drained upper limit (theta(DUL)) and no more drainage occurs due to gravity. This paper extends the Suleiman-Ritchie model for soil water contents higher than theta(DUL) where soil evaporation rates are usually higher than second stage drying. New algorithms were developed for these wetter conditions that are functions of soil depth and the wetness of the near-surface soil. New model parameters were calibrated with data measured in laboratory soil column studies. The resulting model was integrated into DSSAT-CSM (Decision Support System for Agrotechnology Transfer Cropping Systems Model). Simulated soil evaporation rates and soil water contents obtained using the Suleiman-Ritchie model with the developed extensions and the previous DSSAT soil evaporation model were compared and evaluated with field measurements of soil water content during several drying cycles for parts of 3 yr in North Central Florida. Computed soil water contents from the model agreed well with the measured soil water contents near the surface, and provided more accurate estimations than the original DSSAT soil evaporation model, especially for the 5-cm surface layer.