Evaluation of soil water retention curve model from saturation to oven-dryness and development of pedotransfer functions for predicting model parameters

Soil-water retention curve (SWRC) has a wide application in geoenvironmental engineering from the predication of unsaturated shear strength to transient two-phase flow and stability analyses. Although various SWRC models have been proposed to take into account some influencing factors, less attention has been given to consider the effects of pore fluid osmotic potential. Therefore, the key objective of this study is to extend van Genchten’s model so that osmotic potential is considered as an independent factor governing the SWRC behavior. The new model comprises only six variables, which can be calibrated through minimal experimental measurements. More importantly, most of the model parameters have physical meaning by correlating macroscopic volumetric behavior and general trends of SWRC to osmotic potential. The results of validation tests revealed that the new osmotic-dependent SWRC model can predict the retention data in terms of both total and matric suction for two different soils and various molar concentrations very good. The proposed modeling approach does not require any advanced mercury intrusion porosimetry (MIP) tests, yet it can deliver excellent predictions by calibrating only six parameters which are far less than those incorporated into similar models for saline water permeating through the pore structure.

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Evaluation of soil texture data for estimating soil water retention curve

Canadian Journal of Soil Science ◽

10.4141/cjss08066 ◽

2009 ◽

Vol 89 (4) ◽

pp. 461-471 ◽

Cited By ~ 8

Author(s):

B Ghanbarian-Alavijeh ◽

A M Liaghat

Keyword(s):

Soil Water ◽

Soil Texture ◽

Water Retention ◽

Geometric Mean ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Statistical Parameters ◽

Retention Curve

The soil water retention curve (SWRC) is one of the basic characteristics used in determining soil hydraulic properties, including unsaturated hydraulic conductivity. As its measurement is time consuming and difficult, much effort has been expended to develop indirect methods, such as pedotransfer functions and empirical relationships, to estimate SWRC. In this study, three methods were evaluated based on estimation of retention models parameters and, consequently, the soil water retention curve. For this purpose, soil data collected from three data bases, totaling 72 soil samples with 11 different textures, were used in this study. The statistical parameters such as: MR (mean of residual), RE (relative error), RMSE (root mean square error), AIC (Akaike’s information criterion) and GMER (geometric mean error ratio) showed that the Saxton et al. (1986) method estimates the soil water retention curve better than the other methods.Key words: Pedotransfer function, soil texture, soil water retention curve

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Pedotransfer functions for estimating soil water retention curve of Sicilian soils

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2019.1566710 ◽

2019 ◽

Vol 65 (10) ◽

pp. 1401-1416 ◽

Cited By ~ 9

Author(s):

Mirko Castellini ◽

Massimo Iovino

Keyword(s):

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Retention Curve

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Application of neural network pedotransfer functions to calculate soil water retention curve

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/368/1/012008 ◽

2019 ◽

Vol 368 ◽

pp. 012008

Author(s):

A A Belik ◽

A G Bolotov ◽

E V Shein ◽

A A Kokoreva ◽

A A Levin ◽

...

Keyword(s):

Neural Network ◽

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Retention Curve

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Evaluation of Pedotransfer Functions for Estimating Soil Water Retention Curve of Saline and Saline-Alkali Soils of Iran

Pedosphere ◽

10.1016/s1002-0160(11)60122-7 ◽

2011 ◽

Vol 21 (2) ◽

pp. 230-237 ◽

Cited By ~ 30

Author(s):

Y. ABBASI ◽

B. GHANBARIAN-ALAVIJEH ◽

A.M. LIAGHAT ◽

M. SHORAFA

Keyword(s):

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Retention Curve ◽

Alkali Soils

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Developing Pseudo Continuous Pedotransfer Functions for International Soils Measured with the Evaporation Method and the HYPROP System: I. The Soil Water Retention Curve

Water ◽

10.3390/w12123425 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3425

Author(s):

Amninder Singh ◽

Amir Haghverdi ◽

Hasan Sabri Öztürk ◽

Wolfgang Durner

Keyword(s):

Soil Water ◽

Water Retention ◽

Soil Samples ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Data Set ◽

Retention Curve ◽

Evaporation Method

Direct measurements of soil hydraulic properties are time-consuming, challenging, and often expensive. Therefore, their indirect estimation via pedotransfer functions (PTFs) based on easily collected properties like soil texture, bulk density, and organic matter content is desirable. This study was carried out to assess the accuracy of the pseudo continuous neural network PTF (PCNN-PTF) approach for estimating the soil water retention curve of 153 international soils (a total of 12,654 measured water retention pairs) measured via the evaporation method. In addition, an independent data set from Turkey (79 soil samples with 7729 measured data pairs) was used to evaluate the reliability of the PCNN-PTF. The best PCNN-PTF showed high accuracy (root mean square error (RMSE) = 0.043 cm3 cm−3) and reliability (RMSE = 0.061 cm3 cm−3). When Turkish soil samples were incorporated into the training data set, the performance of the PCNN-PTF was enhanced by 33%. Therefore, to further improve the performance of the PCNN-PTF for new regions, we recommend the incorporation of local soils, when available, into the international data sets and developing new sets of PCNN-PTFs.

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Comparison Of Selected Pedotransfer Functions For The Determination Of Soil Water Retention Curves

Slovak Journal of Civil Engineering ◽

10.1515/sjce-2015-0016 ◽

2015 ◽

Vol 23 (3) ◽

pp. 33-36 ◽

Cited By ~ 3

Author(s):

Michal Kupec ◽

Peter Stradiot ◽

Štefan Rehák

Keyword(s):

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Undisturbed Soil ◽

Retention Curve ◽

Van Genuchten Model

Abstract Soil water retention curves were measured using a sandbox and the pressure plate extractor method on undisturbed soil samples from the Borská Lowland. The basic soil properties (e.g. soil texture, dry bulk density) of the samples were determined. The soil water retention curve was described using the van Genuchten model (Van Genuchten, 1980). The parameters of the model were obtained using the RETC program (Van Genuchten et al., 1991). For the determination of the soil water retention curve parameters, two pedotransfer functions (PTF) were also used that were derived for this area by Skalová (2003) and the Rosetta computer program (Schaap et al., 2001). The performance of the PTFs was characterized using the mean difference and root mean square error.

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Estimation of the soil water retention curve (SWRC) using pedotransfer functions (PTFs)

Soil and Water Research ◽

10.17221/2106-swr ◽

2008 ◽

Vol 2 (No. 4) ◽

pp. 113-122 ◽

Cited By ~ 8

Author(s):

S. Matula ◽

M. Mojrová ◽

K. Špongrová

Keyword(s):

Czech Republic ◽

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

The Czech Republic ◽

Retention Curve ◽

Parameter Fitting

Soil hydraulic characteristics, especially the soil water retention curve and hydraulic conductivity, are essential for many agricultural, environmental, and engineering applications. Their measurement is time-consuming and thus costly. Hence, many researchers focused on methods enabling their indirect estimation. In this paper, Wösten’s continuous pedotransfer functions were applied to the data from a selected locality in the Czech Republic, Ti&scaron;ice. The available data set related to this locality consists of 140 measured soil water retention curves, and the information about the soil texture, bulk density ρd, and organic matter content determined at the same time. Own continuous pedotransfer functions were derived, following the methodology used in continuous pedotransfer functions. Two types of fitting, 4-parameters and 3-parameters, were tested. In 4-parameter fitting, all parameters of the van Genuchten’s equation, θs, θr, α, n, were optimized; in 3-parameter fitting, only three parameters, θr, α, n, were optimised while the measured value of θs was set as constant. Based on the results, it can be concluded that the general equations of Wösten’s pedotransfer functions are not very suitable to estimate the soil water retention curves for the locality Ti&scaron;ice in the Czech Republic. However, the parameters of the same Wösten’s equations, which were calculated only from the data for each particular locality, performed much better. The estimates can be improved if the value for the saturated soil water content θs is known, applied and not optimised (the case of 3-parameter fitting). It can be advantageous to estimate SWRC for a locality with no data available, using PTFs and the available basic soil properties. In addition, to measure some retention curves and/or some their parameters, like θs, can improve the accuracy of the SWRC estimation.

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Derivation and validation of pedotransfer functions for estimating soil water retention curve using a variety of soil data

Soil Use and Management ◽

10.1111/j.1475-2743.2009.00254.x ◽

2010 ◽

Vol 26 (1) ◽

pp. 68-74 ◽

Cited By ~ 28

Author(s):

S. Ghorbani Dashtaki ◽

M. Homaee ◽

H. Khodaverdiloo

Keyword(s):

Soil Water ◽

Water Retention ◽

Pedotransfer Functions ◽

Water Retention Curve ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Retention Curve

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Effects of various input levels and different soil water retention curve models on water content estimation using different statistical methods

Hydrology Research ◽

10.2166/nh.2015.219 ◽

2015 ◽

Vol 47 (2) ◽

pp. 312-332 ◽

Cited By ~ 1

Author(s):

Hossein Bayat ◽

Eisa Ebrahimi

Keyword(s):

Water Content ◽

Soil Water ◽

Water Retention ◽

Water Retention Curve ◽

Model Parameters ◽

Soil Water Retention Curve ◽

Soil Water Retention ◽

Retention Curve ◽

Input Variables ◽

Gardner Model

This study investigated the impact of different input variables on the predictability of the water content using soil water retention curve (SWRC) models. The particle and aggregate size distribution model parameters were calculated by fitting the Perrier model to the related distributions for 75 soil samples. Nine SWRC models were fitted to the experimental data and their coefficients were obtained. The regression method was used to estimate the coefficients for nine SWRC models at three input levels. Cluster analysis classified the SWRC models into more homogeneous groups according to the accuracy of their predictions. The SWRC estimated using the Gardner model had the highest accuracy, but it was not an appropriate model for the soils because of its low fitting accuracy. Boltzman, Campbell, and Fermi models obtained the highest accuracy after the Gardner model. The Durner model yielded the lowest prediction accuracy due to the lack of correlation between the input variables and coefficients in this model. Thus, the water content predictions obtained using different SWRC models varied because different input variables were employed.

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