土壤水力特性异质性对土壤排水影响的瞬态随机分析
土壤剖面水分入渗及再分布对生态和水文建模十分重要,而土壤异质性导致垂向的导水率值差异非常大。因此,该文假设在单位梯度下,用微扰法和运动波模型并结合随机分析研究一维瞬态土壤剖面排水的问题。采用Brooks-Corey模型,设饱和导水率和模型参数为随机变量。结果表明:1)饱和导水率方差增大对排水过程具有减缓的作用,有效饱和导水率较小;2)土壤导水率异质性越大,土壤蓄水能力越强;3)比较模型参数的波动与饱和导水率方差和模型参数的协方差,饱和导水率方差对排水影响更大;4)田间排水试验的结论与模型预测相一致。研究可为以长期自我维持的生态系统和高田间持水量为目标的土壤复垦提供依据。...
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Published in | 农业工程学报 Vol. 32; no. 24; pp. 107 - 113 |
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Main Author | |
Format | Journal Article |
Language | Chinese |
Published |
中国农业大学土壤与水科学系,北京,100193%西北农林科技大学水利与建筑工程学院,杨凌,712100
2016
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Subjects | |
Online Access | Get full text |
ISSN | 1002-6819 |
DOI | 10.11975/j.issn.1002-6819.2016.24.014 |
Cover
Summary: | 土壤剖面水分入渗及再分布对生态和水文建模十分重要,而土壤异质性导致垂向的导水率值差异非常大。因此,该文假设在单位梯度下,用微扰法和运动波模型并结合随机分析研究一维瞬态土壤剖面排水的问题。采用Brooks-Corey模型,设饱和导水率和模型参数为随机变量。结果表明:1)饱和导水率方差增大对排水过程具有减缓的作用,有效饱和导水率较小;2)土壤导水率异质性越大,土壤蓄水能力越强;3)比较模型参数的波动与饱和导水率方差和模型参数的协方差,饱和导水率方差对排水影响更大;4)田间排水试验的结论与模型预测相一致。研究可为以长期自我维持的生态系统和高田间持水量为目标的土壤复垦提供依据。 |
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Bibliography: | 11-2047/S Diao Wanying1, Liu Gang1, Si Bingcheng2 (1. Department of Soil and Water, China Agricultural University, Beijing 100193, China; 2. College of Water Resources and Arehitecture Engineering, Northwest A&F University, Yangling 712100, China) Water draining and redistribution from soil profiles is important for both ecological and hydrological modeling.In reality,the vertical hydraulic conductivity is highly variable because of the heterogeneity of soil.Therefore,the objectives of this study were 1) to conduct the stochastic analysis of a one-dimensional transient drainage problem under a unit gradient assumption; 2) to quantify the influence of uncertainty of the hydraulic conductivity using the perturbation method and kinematic wave model; and 3) to verify the stochastic analysis and the analytical solution.Field experiments were carried out at 2 experimental sites(site A: 57°05'57'' N,111°38'54'' W and site B: 56°56'36'' N,111°31'57'' W) in the north of Fort McM urray,northeastern Alberta,Canada.A doubl |
ISSN: | 1002-6819 |
DOI: | 10.11975/j.issn.1002-6819.2016.24.014 |