土壤湿度动态的双层数值模型:模型评估和贝叶斯不确定性估计
Junhao He1, Mohamed M Hantush2, Latif Kalin3
1State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, 712100, China.
Journal of hydrology
|June 16, 2023
概括
这项研究验证了一种两层土壤水模型,用于模拟瓦多斯区的水分和流量. 该模型在各种土壤类型和水气候条件中可靠地运行,对于参数识别和不确定性估计是有效的.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 土壤科学 土壤科学
背景情况:
- 使用理查德方程 (RE) 开发了一种模拟瓦多斯区土壤水运动的两层模型.
- 该模型估计了厚度平均的土壤水分和吸水,与HYDRUS对统一的土壤纹理进行验证.
- 它在分层土壤和现实环境中的表现需要进一步研究.
研究的目的:
- 严格测试两层模型在分层土壤和在可变的田间水气候条件下的性能.
- 用贝叶斯框架估计模型参数并量化不确定性.
- 评估模型在模拟土壤水分和剂区的流动方面的可靠性.
主要方法:
- 对231种土壤纹理和分层土壤形状进行了数值验证实验.
- 通过将土壤湿度和流量估计与HYDRUS模拟进行比较来评估模型性能.
- 一个案例研究利用了土壤气候分析网络 (SCAN) 网站的数据,使用贝叶斯蒙特卡洛 (BMC) 方法进行校准和不确定性量化.
主要成果:
- 两层模型在均的土壤形状上表现出色,在较粗的土壤或较厚的层中略有下降.
- 在分层土壤中,通过对比的液压导电性,实现了对土壤水分和流量的精确模拟.
- 现场应用显示出与观察到的土壤湿度 (RMSE <0.023) 的良好一致性,参数不确定性最小.
结论:
- 两层模型可靠地模拟厚度平均的土壤湿度,并估计在不同条件下的度区域流动.
- 贝叶斯蒙特卡洛 (BMC) 方法提供了一个强大的框架,用于参数识别和不确定性估计在vadose区域建模.
- 该模型适用于需要模拟动态水表的土壤水运动在根区和瓦多斯区的应用.
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