One-dimensional expression to calculate specific yield for shallow groundwater systems with microrelief

Research output: Contribution to journalArticleResearchpeer review

Authors

  • Ullrich Dettmann
  • Michel Bechtold

External Research Organisations

  • Johann Heinrich von Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries
View graph of relations

Details

Original languageEnglish
Pages (from-to)334-340
Number of pages7
JournalHydrological processes
Volume30
Issue number2
Publication statusPublished - 15 Jan 2016

Abstract

Although the importance to account for microrelief in the calculation of specific yields for shallow groundwater systems is well recognized, the microrelief influence is often treated very simplified, which can cause considerable errors. We provide a general one-dimensional expression that correctly represents the effect of a microrelief on the total specific yield that is composed of the soil and surface specific yield. The one-dimensional expression can be applied for different soil hydraulic parameterizations and soil surface elevation frequency distributions. Applying different van Genuchten parameters and a simple linear microrelief model, we demonstrate that the specific yield is influenced by the microrelief not only when surface storage directly contributes to specific yield by (partial) inundation but also when water levels are lower than the minimum surface elevation. Compared with a simplified representation of the soil specific yield, in which a mean soil surface is assumed for the calculation of soil specific yield, the correct representation can lead to lower as well as higher soil specific yields depending on the specific interaction of the soil water retention characteristics and the microrelief. The new equation can be used to obtain more accurate evapotranspiration estimates from water level fluctuations and to account for the effect of microtopographic subgrid variability on simulated water levels of spatially distributed hydrological models.

Keywords

    Microrelief, Specific yield, Surface storage, Van genuchten, Water table fluctuation

ASJC Scopus subject areas

Cite this

One-dimensional expression to calculate specific yield for shallow groundwater systems with microrelief. / Dettmann, Ullrich; Bechtold, Michel.
In: Hydrological processes, Vol. 30, No. 2, 15.01.2016, p. 334-340.

Research output: Contribution to journalArticleResearchpeer review

Download
@article{fe5d50b8ca7a4d268748b5d2d347a2d7,
title = "One-dimensional expression to calculate specific yield for shallow groundwater systems with microrelief",
abstract = "Although the importance to account for microrelief in the calculation of specific yields for shallow groundwater systems is well recognized, the microrelief influence is often treated very simplified, which can cause considerable errors. We provide a general one-dimensional expression that correctly represents the effect of a microrelief on the total specific yield that is composed of the soil and surface specific yield. The one-dimensional expression can be applied for different soil hydraulic parameterizations and soil surface elevation frequency distributions. Applying different van Genuchten parameters and a simple linear microrelief model, we demonstrate that the specific yield is influenced by the microrelief not only when surface storage directly contributes to specific yield by (partial) inundation but also when water levels are lower than the minimum surface elevation. Compared with a simplified representation of the soil specific yield, in which a mean soil surface is assumed for the calculation of soil specific yield, the correct representation can lead to lower as well as higher soil specific yields depending on the specific interaction of the soil water retention characteristics and the microrelief. The new equation can be used to obtain more accurate evapotranspiration estimates from water level fluctuations and to account for the effect of microtopographic subgrid variability on simulated water levels of spatially distributed hydrological models.",
keywords = "Microrelief, Specific yield, Surface storage, Van genuchten, Water table fluctuation",
author = "Ullrich Dettmann and Michel Bechtold",
note = "Publisher Copyright: {\textcopyright} 2016 John Wiley & Sons, Ltd. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.",
year = "2016",
month = jan,
day = "15",
doi = "10.1002/hyp.10637",
language = "English",
volume = "30",
pages = "334--340",
journal = "Hydrological processes",
issn = "0885-6087",
publisher = "John Wiley and Sons Ltd",
number = "2",

}

Download

TY - JOUR

T1 - One-dimensional expression to calculate specific yield for shallow groundwater systems with microrelief

AU - Dettmann, Ullrich

AU - Bechtold, Michel

N1 - Publisher Copyright: © 2016 John Wiley & Sons, Ltd. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2016/1/15

Y1 - 2016/1/15

N2 - Although the importance to account for microrelief in the calculation of specific yields for shallow groundwater systems is well recognized, the microrelief influence is often treated very simplified, which can cause considerable errors. We provide a general one-dimensional expression that correctly represents the effect of a microrelief on the total specific yield that is composed of the soil and surface specific yield. The one-dimensional expression can be applied for different soil hydraulic parameterizations and soil surface elevation frequency distributions. Applying different van Genuchten parameters and a simple linear microrelief model, we demonstrate that the specific yield is influenced by the microrelief not only when surface storage directly contributes to specific yield by (partial) inundation but also when water levels are lower than the minimum surface elevation. Compared with a simplified representation of the soil specific yield, in which a mean soil surface is assumed for the calculation of soil specific yield, the correct representation can lead to lower as well as higher soil specific yields depending on the specific interaction of the soil water retention characteristics and the microrelief. The new equation can be used to obtain more accurate evapotranspiration estimates from water level fluctuations and to account for the effect of microtopographic subgrid variability on simulated water levels of spatially distributed hydrological models.

AB - Although the importance to account for microrelief in the calculation of specific yields for shallow groundwater systems is well recognized, the microrelief influence is often treated very simplified, which can cause considerable errors. We provide a general one-dimensional expression that correctly represents the effect of a microrelief on the total specific yield that is composed of the soil and surface specific yield. The one-dimensional expression can be applied for different soil hydraulic parameterizations and soil surface elevation frequency distributions. Applying different van Genuchten parameters and a simple linear microrelief model, we demonstrate that the specific yield is influenced by the microrelief not only when surface storage directly contributes to specific yield by (partial) inundation but also when water levels are lower than the minimum surface elevation. Compared with a simplified representation of the soil specific yield, in which a mean soil surface is assumed for the calculation of soil specific yield, the correct representation can lead to lower as well as higher soil specific yields depending on the specific interaction of the soil water retention characteristics and the microrelief. The new equation can be used to obtain more accurate evapotranspiration estimates from water level fluctuations and to account for the effect of microtopographic subgrid variability on simulated water levels of spatially distributed hydrological models.

KW - Microrelief

KW - Specific yield

KW - Surface storage

KW - Van genuchten

KW - Water table fluctuation

UR - http://www.scopus.com/inward/record.url?scp=84955209814&partnerID=8YFLogxK

U2 - 10.1002/hyp.10637

DO - 10.1002/hyp.10637

M3 - Article

AN - SCOPUS:84955209814

VL - 30

SP - 334

EP - 340

JO - Hydrological processes

JF - Hydrological processes

SN - 0885-6087

IS - 2

ER -