Travel times in the vadose zone: Variability in space and time

Matthias Sprenger, Stefan Seeger, Theresa Blume, Markus Weiler

Research output: Contribution to journalArticle

44 Citations (Scopus)
13 Downloads (Pure)

Abstract

Water travel times reflect hydrological processes, yet we know little about how travel times in the unsaturated zone vary with time. Using the soil physical model HYDRUS-1D we derived time variable travel time distributions for 35 study sites within the Attert catchment in Luxembourg. While all sites experience similar climatic forcing, they differ with regard to soil types (16 Cambisols, 12 Arenosols, and 7 Stagnosols) and the vegetation cover (29 forest, 6 grassland). We estimated site specific water flow and transport parameters by fitting the model simulations to observed soil moisture time series and depth profiles of pore water stable isotopes. With the calibrated model we tracked the water parcels introduced with each rainfall event over a period of several years. Our results show that the median travel time of water from the soil surface to depths down to 200 cm is mainly driven by the subsequent rainfall amounts. The median time until precipitation is taken up by roots is governed by the seasonality of evapotranspiration rates. The ratio between the amount of water that leaves the soil profile by on the one hand and evaporation and transpiration on the other hand also shows an annual cycle. This time variable response due to climatic forcing is furthermore visible in the multi-modal nature of the site specific master transit time distribution representing the flow averaged probability density for rain water to become recharge. The spatial variability of travel times is mainly driven by soil texture and structure, with significant longer travel times for the clayey Stagnosols than for the loamy to sandy Cambisols and Arenosols.
Original languageEnglish
Pages (from-to)5727–5754
Number of pages28
JournalWater Resources Research
Volume52
Issue number8
Early online date3 Jun 2016
DOIs
Publication statusPublished - 5 Aug 2016

Fingerprint

vadose zone
travel time
Arenosol
Cambisol
water
rainfall
soil structure
annual cycle
transpiration
vegetation cover
seasonality
soil profile
evapotranspiration
soil type
water flow
recharge
porewater
soil surface
stable isotope
evaporation

Keywords

  • Vadose zone
  • Modeling
  • Soils
  • Catchment
  • Stable isotopes

Cite this

Sprenger, M., Seeger, S., Blume, T., & Weiler, M. (2016). Travel times in the vadose zone: Variability in space and time. Water Resources Research, 52(8), 5727–5754. https://doi.org/10.1002/2015WR018077

Travel times in the vadose zone : Variability in space and time. / Sprenger, Matthias; Seeger, Stefan; Blume, Theresa; Weiler, Markus.

In: Water Resources Research, Vol. 52, No. 8, 05.08.2016, p. 5727–5754.

Research output: Contribution to journalArticle

Sprenger, M, Seeger, S, Blume, T & Weiler, M 2016, 'Travel times in the vadose zone: Variability in space and time', Water Resources Research, vol. 52, no. 8, pp. 5727–5754. https://doi.org/10.1002/2015WR018077
Sprenger, Matthias ; Seeger, Stefan ; Blume, Theresa ; Weiler, Markus. / Travel times in the vadose zone : Variability in space and time. In: Water Resources Research. 2016 ; Vol. 52, No. 8. pp. 5727–5754.
@article{fe04838fe11746cb828cfe893bd18500,
title = "Travel times in the vadose zone: Variability in space and time",
abstract = "Water travel times reflect hydrological processes, yet we know little about how travel times in the unsaturated zone vary with time. Using the soil physical model HYDRUS-1D we derived time variable travel time distributions for 35 study sites within the Attert catchment in Luxembourg. While all sites experience similar climatic forcing, they differ with regard to soil types (16 Cambisols, 12 Arenosols, and 7 Stagnosols) and the vegetation cover (29 forest, 6 grassland). We estimated site specific water flow and transport parameters by fitting the model simulations to observed soil moisture time series and depth profiles of pore water stable isotopes. With the calibrated model we tracked the water parcels introduced with each rainfall event over a period of several years. Our results show that the median travel time of water from the soil surface to depths down to 200 cm is mainly driven by the subsequent rainfall amounts. The median time until precipitation is taken up by roots is governed by the seasonality of evapotranspiration rates. The ratio between the amount of water that leaves the soil profile by on the one hand and evaporation and transpiration on the other hand also shows an annual cycle. This time variable response due to climatic forcing is furthermore visible in the multi-modal nature of the site specific master transit time distribution representing the flow averaged probability density for rain water to become recharge. The spatial variability of travel times is mainly driven by soil texture and structure, with significant longer travel times for the clayey Stagnosols than for the loamy to sandy Cambisols and Arenosols.",
keywords = "Vadose zone, Modeling, Soils, Catchment, Stable isotopes",
author = "Matthias Sprenger and Stefan Seeger and Theresa Blume and Markus Weiler",
year = "2016",
month = "8",
day = "5",
doi = "10.1002/2015WR018077",
language = "English",
volume = "52",
pages = "5727–5754",
journal = "Water Resources Research",
issn = "0043-1397",
publisher = "American Geophysical Union",
number = "8",

}

TY - JOUR

T1 - Travel times in the vadose zone

T2 - Variability in space and time

AU - Sprenger, Matthias

AU - Seeger, Stefan

AU - Blume, Theresa

AU - Weiler, Markus

PY - 2016/8/5

Y1 - 2016/8/5

N2 - Water travel times reflect hydrological processes, yet we know little about how travel times in the unsaturated zone vary with time. Using the soil physical model HYDRUS-1D we derived time variable travel time distributions for 35 study sites within the Attert catchment in Luxembourg. While all sites experience similar climatic forcing, they differ with regard to soil types (16 Cambisols, 12 Arenosols, and 7 Stagnosols) and the vegetation cover (29 forest, 6 grassland). We estimated site specific water flow and transport parameters by fitting the model simulations to observed soil moisture time series and depth profiles of pore water stable isotopes. With the calibrated model we tracked the water parcels introduced with each rainfall event over a period of several years. Our results show that the median travel time of water from the soil surface to depths down to 200 cm is mainly driven by the subsequent rainfall amounts. The median time until precipitation is taken up by roots is governed by the seasonality of evapotranspiration rates. The ratio between the amount of water that leaves the soil profile by on the one hand and evaporation and transpiration on the other hand also shows an annual cycle. This time variable response due to climatic forcing is furthermore visible in the multi-modal nature of the site specific master transit time distribution representing the flow averaged probability density for rain water to become recharge. The spatial variability of travel times is mainly driven by soil texture and structure, with significant longer travel times for the clayey Stagnosols than for the loamy to sandy Cambisols and Arenosols.

AB - Water travel times reflect hydrological processes, yet we know little about how travel times in the unsaturated zone vary with time. Using the soil physical model HYDRUS-1D we derived time variable travel time distributions for 35 study sites within the Attert catchment in Luxembourg. While all sites experience similar climatic forcing, they differ with regard to soil types (16 Cambisols, 12 Arenosols, and 7 Stagnosols) and the vegetation cover (29 forest, 6 grassland). We estimated site specific water flow and transport parameters by fitting the model simulations to observed soil moisture time series and depth profiles of pore water stable isotopes. With the calibrated model we tracked the water parcels introduced with each rainfall event over a period of several years. Our results show that the median travel time of water from the soil surface to depths down to 200 cm is mainly driven by the subsequent rainfall amounts. The median time until precipitation is taken up by roots is governed by the seasonality of evapotranspiration rates. The ratio between the amount of water that leaves the soil profile by on the one hand and evaporation and transpiration on the other hand also shows an annual cycle. This time variable response due to climatic forcing is furthermore visible in the multi-modal nature of the site specific master transit time distribution representing the flow averaged probability density for rain water to become recharge. The spatial variability of travel times is mainly driven by soil texture and structure, with significant longer travel times for the clayey Stagnosols than for the loamy to sandy Cambisols and Arenosols.

KW - Vadose zone

KW - Modeling

KW - Soils

KW - Catchment

KW - Stable isotopes

U2 - 10.1002/2015WR018077

DO - 10.1002/2015WR018077

M3 - Article

VL - 52

SP - 5727

EP - 5754

JO - Water Resources Research

JF - Water Resources Research

SN - 0043-1397

IS - 8

ER -