Recent Applications of the HYDRUS2D Software Future Plans

1
Recent Applications of the HYDRUS-2D Software
Future Plans Jirka Simunek and Martinus Th.
van Genuchten Martha P.L. Whitaker George E.
Brown, Jr., Salinity Laboratory, Riverside
CA Department of Hydrology Water
Resources The University of
Arizona, Tucson
Introduction HYDRUS-2D is a Windows-based
computer software package for simulation water,
heat and/or solute movement in two-dimensional
variably-saturated media. The software has been
used in the past few year in a large number of
applications, including several projects within
the STC. In this poster we list some of these
applications, as well as discuss some of new
processes that we plan to include in the software
package within the next two years.
Future Plans New processes a) Coupled
movement of water and energy, including vapor
transport b) An energy balance at the soil
surface - the Penman-Monteith method for
calculating of potential evapotranspiration FAO,
1990 - partitioning of potential ET into
potential evaporation and potential transpiration
based on LAI or the soil cover fraction c)
Nonequilibrium flow and transport (preferential
flow) - dual-porosity approach
(mobile-immobile concept) - dual-permeability
approach (two overlapping porous media, one for
matrix flow, one for preferential flow) Gerke
and van Genuchten, 1993 - kinematic wave
approach for flow in macropores Jarvis, 1991
- simplified first-order approach Ross and
Smettem, 2000 - dual-porosity hydraulic
property models Durner, 1994 d) Multicomponent
solute transport (coupling with PHREEQC
Parkhurst and Appelo, 1999) available
chemical reactions - aqueous complexation
- redox reactions - ion exchange
(Gains-Thomas) - surface complexation
diffuse double-layer model and non-electrostatic
surface complexation model -
precipitation/dissolution - chemical
kinetics - biological reactions e) Overland
flow - kinematic wave approach -
diffusion wave approximation f) Colloid, virus,
and bacteria transport - filtration theory
- colloid facilitated transport - two-site
kinetic sorption - air-water interface -
site-limited sorption g) Dynamic boundary
conditions - switching at given time between
head and flux - switching between seepage
face and atmospheric BC based on the systems
status (streams) - switching between given
pressure head and atmospheric BC based on the
systems status (streams) - multiple
time-dependent boundary conditions -
wells h) Suggestions? Software development a)
Modify graphical interfaces to accommodate new
processes b) Improve graphical capabilities and
user-friendliness of existing software -
graphs of multiple variables c) Improve
documentation of existing software, including new
and better user manuals d) Develop HYDRUS-3D for
simulating three-dimensional water, heat and
solute movement
Application of HYDRUS-2D to Riparian Hydrology in
the San Pedro River Basin
HYDRUS-2D has been used in studies of riparian
hydrology to estimate bank storage and
transpiration rates for cottonwood and willow
trees in the San Pedro Riparian National
Conservation Area (SPRNCA) Whitaker, 2000.
Bank storage is the volume of water that enters
a rivers banks during a high flow event. It is
typically a difficult to quantify parameter,
reason why bank storage is often neglected. With
the use of HYDRUS-2D, Martha Whitaker offered a
quantified estimate of bank storage for several
high flow events in 1997, and concluded that it
is not a negligible quantity, especially when one
considers models for groundwater-surface water
(i.e. aquifer-stream) interactions. HYDRUS-2D can
provide visual representations of the flow
reversal during which bank storage occurs. Each
figure to the right shows the same cross-section
of a river bank, with the soil surface at the top
and the river to the left of the riverbank.
Figure (a) shows the flow conditions at the
beginning of a precipitation event, before the
river stage has risen significantly. Figure (b)
shows the reversal of flow that occurs with a
rise in the stream stage, and Figure (c) shows
the sustained flow reversal. HYDRUS-2D also
supported a second conclusion offered by
Whitaker. For rivers which gain water from an
adjacent aquifer, rises in the river stage can
cause a back-up of baseflow when bank storage
occurs. Based on HYDRUS-2D simulations, Whitaker
concluded that baseflow back-up, as an effect of
bank storage, potentially provides several months
of water reserves for a riparian forest
gallery. Transpiration from riparian forest
galleries is another parameter that is often
difficult to quantify, and is critically
important for understanding riparian water
budgets in semi-arid regions. Whitakers use of
HYDRUS-2D also resulted in an estimate of
transpiration rates for cottonwood and willow
trees in the riparian forest gallery, based on
the models calculation of root water uptake.
The transpiration estimate was generally
consistent with other estimates for the same area
Scott 1999.

• Recent Applications
• Recent applications within the STC
• Identification of hydrologic exchange between
  stream and riparian zones
• Evaluation of effects of small and large pipes
  observed in many indurated calcic horizons in New
  Mexico on ground water recharge.
• Other applications
• Analysis of virus transport at the field scale
  Schijven, J., and J. imunek, Kinetic modeling
  of virus transport at field scale, J. of Contam.
  Hydrology, submitted.
• Development of root water uptake models for
  sprinkler-irrigated treesVrugt, J. A., J. W.
  Hopmans, and J. imunek, Calibration of a
  two-dimensional root water uptake model for a
  sprinkler-irrigated almond tree, Soil Sci. Soc.
  Am. J., in press.Vrugt, J.A., M. T. van Wijk, J.
  W. Hopmans, and J. imunek, Comparison of one,
  two, and three dimensional root water uptake in
  transient flow modeling around a
  sprinkler-irrigated almond tree, Water Resour.
  Res., submitted.
• Analysis of water content and temperature
  profiles around land minesDas, B.S., J. M. H.
  Hendrickx, and B. Borchers. 2000. Modeling
  transient water distribution around landmines in
  bare soils, Soil Science, in press.Hendrickx, J.
  M. H., J. imçnek and B. Borchers. 2000. Modeling
  transient water and temperature distribution
  around landmines in bare soils, Soil Science, in
  preparation.
• Development of a new method for slug-test
  analyses for large-diameter, hand-dug wellsRupp,
  D. E., J. S. Selker, and J. imunek, A
  modification to the Bouwer and Rice method of
  slug-test analysis for large-diameter, hand-dug
  wells, Groundwater, in press.
• Analysis of nearshore recharge in a mantled karst
  terrainLee, T. M., Effects of nearshore recharge
  on groundwater interactions with a lake in
  mantled karst terrain, Water Resour. Rer., 36(8),
  2167-2182, 2000.
• Performance of protective capillary
  barriersMallants, D., G. Volckaert, and J.
  Marivoet, Sensitivity of protective barrier
  performance to changes in rainfall rate, Waste
  Management 19, 467-475, 1999.
• Analysis of water flow and solute transport under
  field conditions De Vos, J. A., D. Hesterberg,
  and P. A. C. Raats, Nitrate leaching in a
  tile-drained silt loam soil, Soil Sci. Soc. Am.
  J., 64, 517-527, 2000.Pang, L., M. E. Close,
  J.P.C. Watt, and K. W. Vincent, Simulation of
  picloram, atrazin, and simazine leaching through
  two New Zealand soils and into groundwater using
  HYDRUS-2D, J. of Contam. Hydrology, 44(1), 19-46,
  2000.Abbaspour, K. C., A. Kohler, J. imunek, M.
  Fritsch, and R. Schulin, Application of a
  two-dimensional model to simulate flow and
  transport in a macroporous agricultural field
  with tile drains, European J. of Soil Sci., in
  press.
• Analysis of recharge from a subsidence crater at
  the Nevada test site Wilson, G. V., D. M. Ely,
  S. L. Hokett, and D. R. Gillespie, Recharge from
  a subsidence crater at the Nevada test site, Soil
  Sci. Soc. Am. J., 64(5), 1560-1581, 2000.
• Analysis of heat pulse probe data Hopmans, J.
  W., J. imunek, and K. L. Bristow, Indirect
  estimation of soil thermal properties and water
  flux from heat pulse measurements Geometry and
  Dispersion effects, Water Resour. Res., submitted
  
• Analysis of the water regime of historical
  buildings and monuments Ishizaki, T., N.
  Kuchitsu, T. Nishiura, and J. imçnek, Analysis
  of water regime in historical brick buildings in
  Ayutthaya, Thailand, Science for Conservation,
  38, 154-163, in Japanese with English summary,
  1999.
• and many others.

t 356.25 days
t 357.00 days
t 357.25 days
Flowing Particles
Particles around a Capillary Barrier
Flow Along a Vertical Transect with a Stream
Alternative Furrow Irrigation
For more information contact Jirka Simunek and
Rien van Genuchten George E. Brown, Jr., Salinity
Laboratory (USDA-ARS) 450 W. Big Springs
Road Riverside CA 92507 JSimunek_at_ussl.ars.usda.gov
Tel [phone] Fax [phone]