Comparison of Seven Weibull Distribution Models for Predicting Relative Hydraulic Conductivity. Issue 5 (6th May 2022)

• Record Type: Journal Article
• Authors: Shan, Jipeng; Yang, Zhenlei; Kuang, Xingxing; Li, Ling; Liu, Junguo
• Is Part Of: Water resources research. Volume 58:Issue 5(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-06
• Subjects: relative hydraulic conductivity -- water retention curve -- Weibull pore size distribution -- water flow modeling -- unsaturated soils; Hydrology -- Periodicals; 333.91
• DOI: 10.1029/2021WR030683
• Languages: English
• ISSNs: 0043-1397

Abstract

Abstract: Modeling water flow in unsaturated soils requires accurate characterization of relative hydraulic conductivity (RHC) and water retention curve (WRC). The overall objective of this study is to investigate the performances of seven Weibull distribution models for predicting RHC using the Assouline et al. (1998), https://doi.org/10.1029/97WR03039 WRC. Specifically, a new RHC model was proposed via the approach of Assouline (2001), https://doi.org/10.1029/2000WR900254 with the assumptions of Burdine (1953), https://doi.org/10.2118/225-G and Kosugi (1999), https://doi.org/10.2136/sssaj1999.03615995006300020003x . The proposed model, together with the other six models, was then compared with data from 40 soils to explore their predictive performances for RHC. The results showed that the proposed model provides the best agreement with measured data and yields a 16.1% improvement in RHC prediction compared to the widely used Assouline et al. (1998), https://doi.org/10.1029/97WR03039 ‐Mualem (1976), https://doi.org/10.1029/WR012i003p00513 model. The proposed model can be used as RHC parameterization for water flow modeling in the unsaturated zone. Key Points: A model is proposed based on the method of Assouline (2001), https://doi.org/10.1029/2000WR900254 together with the assumptions of Burdine (1953), https://doi.org/10.2118/225-G and Kosugi (1999), https://doi.org/10.2136/sssaj1999.03615995006300020003x The proposed model improves the fit of the predicted relative hydraulic conductivity to measured soil data The proposed model outperforms the other six models (AP, AB, AAS, AM, AA05, and AA16) for the prediction of relative hydraulic conductivity