Evaluating the prediction of two unsaturated hydraulic conductivity models by considering parameters uncertainty

Document Type : Original Article

Authors

1 Ferdowsi university of Mashhad

2 Department of water engineering, Faculty of agriculture, Ferdowsi University of Mashhad, Iran

3 Professor, Faculty of Natural Resources and Environment and invited prof. of Dept of Water Eng., Ferdowsi University of Mashhad., Mashhad., Iran

4 Assistant professor in civil engineering department, Boise state university, Idaho, U.S.A.

Abstract

Unsaturated hydraulic conductivity (K(θ)) is proportional to volumetric water content in vadose zone and the obtained K(θ) curve is crucial for modeling the soil water movement. Numerous theories and models have been recently proposed regarding the estimation of K(θ) that despite improving model predictions, each has a disadvantage of its own. The critical path analysis from percolation theory attempts to improve the prediction of K(θ) by simplifying the complex geometry of the porous medium. In addition, the recently developed Peters-Durner-Iden model (PDI) has shown high potential for prediction of K(θ). In this research, both percolation theory and PDI models are evaluated. Also, by using Monte Carlo- Markov chain method, the uncertainty of the simulated parameters is assessed. In this study, the Hybrid-Evolution Monte Carlo-Markov chain algorithm has been utilized, that employs adaptive metropolis, differential-evolution, and Snooker update algorithms, which minimizes the number of iterations required to search parametric space. Goodness of fit measures shows higher results for prediction of K(θ) by percolation theory and in every case except for a single soil, the Nash–Sutcliffe criterion was higher than 0.9. In addition, the number of parameters required for the PDI model is more than percolation theory, which leads to an increase in parameter- associated uncertainty. It is also discussed that it is possible to reduce the number of parameters required by PDI model by applying several constraints. But this method is not applicable to all soil textures. Comparison of the convergence rate of the two models showed that parameters of PDI model in all cases require close to 300 iterations to converge while, percolation theory requires up to 2000 iterations to converge. Therefore, the results indicate that the percolation theory with fewer number of parameters can provide more accurate and reliable estimates of K(θ) and water retention.

Keywords


زرین فر،س.، قهرمان،ب.، داوری،ک. 1390. ارائه توابع انتقالی جهت پیش بینی هدایت هیدرولیکی اشباع خاک های گراولی با استفاده از رگرسیون حداقل مربعات جزئی، آب و خاک. 25: ۶۱۷-۶۲۴.
Alfaro Soto, M.A., Chang, H.K., van Genuchten, M.T., 2017. Fractal-based models for the unsaturated soil hydraulic functions. Geoderma 306, 144–151. doi:10.1016/j.geoderma.2017.07.019
Cihan, A., Sukop, M.C., Tyner, J.S., Perfect, E., Huang, H., 2009. Analytical Predictions and Lattice Boltzmann Simulations of Intrinsic Permeability for Mass Fractal Porous Media. Vadose Zo. J. 8, 187. doi:10.2136/vzj2008.0003
Crawford, J.W., 1994. The relationship between structure and the hydraulic conductivity of soil. Eur. J. Soil Sci. 45, 493–502.
Guarracino, L., Rötting, T., Carrera, J., 2014. A fractal model to describe the evolution of multiphase flow properties during mineral dissolution. Adv. Water Resour. 67, 78–86. doi:10.1016/j.advwatres.2014.02.011
Ghanbarian, B., Hunt, A.G., 2012. Unsaturated hydraulic conductivity in porous media: Percolation theory. Geoderma. 187:77-84.
Ghanbarian, B., Hunt, A.G., Daigle, H., 2016. Fluid flow in porous media with rough pore‐solid interface. Water Resour. Res. 52, 2045–2058
Hunt, A.G., Gee, G.W., 2002. Application of critical path analysis to fractal porous media: Comparison with examples from the Hanford site. Adv. Water Resour. 25, 129–146. doi:10.1016/S0309-1708(01)00057-4
Hunt, A.G., Ghanbarian, B., Saville, K.C., 2013. Unsaturated hydraulic conductivity modeling for porous media with two fractal regimes. Geoderma 207–208, 268–278. doi:10.1016/j.geoderma.2013.05.023
Iden, S. C., Durner, W., 2014. Comment on ‘‘Simple consistent models for water retention and hydraulic conductivity in the complete moisture range’’ by A. Peters,Water Resour. Res., 50, 7530–7534, doi:10.1002/2014WR015937
Kitanidis, P.K., and Bras, R.L., 1980. Real-Time Forecasting with a Conceptual Hydrologic Model. Part I: Analysis of Uncertainty, Water Resources Research. 16: 6.1025-1033
Mehta, B. K., Shiozawa, S.,  Nakano M., 1994. Hydraulic properties of a sandy soil at low water contents. Soil Sci. 157(4), 208–214.
Millington, R., Quirk J. P., 1961. Permeability of porous solids.Trans. Faraday Soc. 57(8), 1200–1207.
Perrier, E., Bird, N.,  Rieu, M., 2000. Generalizing the fractal model of soil structure: the pore—solid fractal approach. Developments in Soil Science. Vol. 27. Elsevier,. 47-74.
Peters, A., 2014. Reply to comment by S. Iden and W. Durner on ‘‘Simple consistent models for water retention and hydraulic conductivity in the complete moisture range’’, Water Resour. Res., 50, 7535–7539, doi:10.1002/2014WR016107
Rieu, M., Sposito, G., 1991. Fractal fragmentation, soil porosity, and soil water properties: I. Theory. Soil Sci. Soc. Am. J. 55, 1231–1238.            
Tyler, S.W., Wheatcraft, S.W., 1989. Application of Fractal Mathematics to Soil Water Retention Estimation. Soil Sci. Soc. Am. J. 53, 987. doi:10.2136/sssaj1989.03615995005300040001x
Sadegh, M., Ragno, E., AghaKouchak, A., 2017. Multivariate Copula Analysis Toolbox (MvCAT): Describing dependence and underlying uncertainty using a Bayesian framework. Water Resour. Res. 53, 5166–5183. doi:10.1002/2016WR020242
Saito, H., Sim˚unek, j., Mohanty, B. P., 2006. Numerical analysis of coupled water, vapor, and heat transport in the vadose zone.Vadose Zone J., 5(2), 784–800, doi:10.2136/vzj2006.0007
Sakai, M., Van Genuchten, M.T., Alazba, A.A., Setiawan, B.I., Minasny, B. A., 2015. complete soil hydraulic model accounting for capillary and adsorptive water retention, capillary and film conductivity, and hysteresis. Water Resources Research. 51(11):8757-72.
Vrugt, J.A., Gupta, H.V., Bouten, W., Sorooshian. S. A., 2003.  Shuffled Complex Evolution Metropolis algorithm for optimization and uncertainty assessment of hydrologic model parameters. Water Resources Research. 39(8).
Vrugt, J.A., Ter Braak, C.J., Diks, C.G., Robinson, B.A., Hyman, J.M., Higdon, D., 2009. Accelerating Markov chain Monte Carlo simulation by differential evolution with self-adaptive randomized subspace sampling. International Journal of Nonlinear Sciences and Numerical Simulation. 10(3):273-90.
Zand-Parsa, S., 2006. Improved soil hydraulic conductivity function based on specific liquid-vapour interfacial area around the soil particles. Geoderma 132, 20–30. doi:10.1016/j.geoderma.2005.04.020
Zand-Parsa, S., Sepaskhah, A.R., 2004. Soil hydraulic conductivity function based on specific liquid-vapor interfacial area around the soil particles. Geoderma 119, 143–157. doi:10.1016/S0016-7061(03)00258-1