Soil moisture data as a constraint for groundwater recharge estimation
File(s)2017JoHmathias.pdf (918.79 KB)
Accepted version
Author(s)
Mathias, SA
Sorensen, JPR
Butler, AP
Type
Journal Article
Abstract
Estimating groundwater recharge rates is important for water resource management studies. Modeling approaches to forecast groundwater recharge typically require observed historic data to assist calibration. It is generally not possible to observe groundwater recharge rates directly. Therefore, in the past, much effort has been invested to record soil moisture content (SMC) data, which can be used in a water balance calculation to estimate groundwater recharge. In this context, SMC data is measured at different depths and then typically integrated with respect to depth to obtain a single set of aggregated SMC values, which are used as an estimate of the total water stored within a given soil profile. This article seeks to investigate the value of such aggregated SMC data for conditioning groundwater recharge models in this respect. A simple modeling approach is adopted, which utilizes an emulation of Richards’ equation in conjunction with a soil texture pedotransfer function. The only unknown parameters are soil texture. Monte Carlo simulation is performed for four different SMC monitoring sites. The model is used to estimate both aggregated SMC and groundwater recharge. The impact of conditioning the model to the aggregated SMC data is then explored in terms of its ability to reduce the uncertainty associated with recharge estimation. Whilst uncertainty in soil texture can lead to significant uncertainty in groundwater recharge estimation, it is found that aggregated SMC is virtually insensitive to soil texture.
Date Issued
2017-06-29
Date Acceptance
2017-06-23
Citation
Journal of Hydrology, 2017, 552, pp.258-266
ISSN
0022-1694
Publisher
Elsevier
Start Page
258
End Page
266
Journal / Book Title
Journal of Hydrology
Volume
552
Copyright Statement
© 2017 Elsevier B.V. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Subjects
Science & Technology
Technology
Physical Sciences
Engineering, Civil
Geosciences, Multidisciplinary
Water Resources
Engineering
Geology
Conditioning
Groundwater recharge
Soil moisture content
Soil texture
Vertical percolation
CHALK
EQUATION
AQUIFERS
PROGRAM
COMPLEXITY
MODELS
SCALE
MD Multidisciplinary
Environmental Engineering
Publication Status
Published