TETRANS Model: Estimates one-dimensional Solute Transport Through the Vadose Zone Under Transient-state Conditions
Entry ID: USDA_ARS_TETRANS
Abstract: TETrans (an acronym for Trace Element Transport) is a functional,
layer-equilibrium model of one-dimensional solute transport through the vadose
zone under transient-state conditions. This type of model is often referred to
as a "tipping-bucket model".
TETrans is a capacity model that defines changes in amounts of solute and water
content rather than rates of change. As such, it is driven by the ... amounts of
rainfall, irrigation, or evapotranspiration and only considers time indirectly
by using the time from one irrigation or precipitation event to another.
TETrans predicts the average concentration of a solute within each defined soil
layer or depth increment. Transport through the soil profile is modeled as a
series of events or processes for a finite collection of discrete depth
intervals. These sequential events or processes include: (i) infiltration and
drainage to field capacity, (ii) instantaneous chemical equilibration for
reactive solutes, (iii) water uptake by the plant root resulting from
transpiration and evaporative losses from the soil surface, and (iv)
instantaneous chemical reequilibration. Each process is assumed to occur in
sequence within a given depth interval as opposed to reality where transport is
a collection of simultaneous processes.
TETrans accounts for the hydraulic and physicochemical processes of water flow
including preferential flow, evapotranspiration with a root growth and water
uptake distribution function, adsorption-desorption, and drainage. The model
determines the vertical profile distributions of total, soluble and adsorbed
concentrations of a solute within and beyond the root zone; soil water content
profile distribution; total drainage; total solute loading beyond the root
zone; plant water uptake distribution; and leaching efficiency.
ISO Topic Category
Access Constraints The program and manual are available upon request from:
USDA-ARS U.S. Salinity Laboratory
450 West Big Springs Road
Riverside, CA 92507-4617
Creation and Review Dates