Switches

Structure of Model > Model Structure

Switches

Value	Meaning
Off	No evaporation loss to the atmosphere is considered.
Simple input style	A simple analytical equation considering only the day number of the year is used to estimate the potential evapotranspiration. Only total evapotranspiration is expressed i.e. no differentiation between transpiration and evaporation is made.
Radiation input style	A physical based equation is used accounting for both the net radiation and the transport of vapour in the atmosphere boundary layer.

GroundWaterFlow

Value	Meaning
Off	Ground water is disregarded and the whole soil profile will be assumed unsaturated.
On	Ground water will be present in the soil profile if any layer reaches saturation. The ground water level will be defined by assuming a continuous zone of saturation from the lower boundary of the soil profile to any level within the soil profile simulated.

Value	Meaning
Off	No heat flows will be calculated. A constant soil temperature is assumed according to selected initial conditions.
On	Heat flows between adjacent soil layers will be calculated.

Value	Meaning
Off	Only precipitation will be considered as input of water for infiltration.
On	Irrigation water is added to the soil in addition to precipitation.

Value	Meaning
No lateral input	No horizontal input of water in any driving variable files.
In driving file	A horizontal flow rate is defined as a dynamic driving variable which will be read from a PG-Bin file during the simulation.
With irrigation	Irrigation water is added directly into the soil profile at different depths.

Nitrogen and Carbon

Value	Meaning
Abiotic driving variables	All the abiotic driving variables have to be defined either as parameter values or as driving variables that must be given to the model from a separate file. The Water and Heat Equations are turned off if this option is selected
Dynamic interaction with abiotics	In this case both Water and Heat Equations must be turned on in order to supply the nitrogen and carbon models with necessary information.
Off	No nitrogen and carbon processes will be simulated.

Value	Meaning
Off	Coupling to the Minteq model is switched off.
On	Coupling to the Minteq model is switched on.

Value	Meaning
No vegetation	A bare soil is assumed.
Implicit big leaf	A simple plant is defined allowing water uptake by roots from different layers in the soil but without any explicit account for soil surface evaporation and transpiration
Explicit one big leaf	A separation is made between soil evaporation and transpiration from canopy. Various options exist for definition of above ground plant characteristics. Dynamic interaction with abiotics is possible.
Explicit big leaves	A separation is made between soil evaporation and transpiration from canopy. Various options exist for definition of above ground plant characteristics. Dynamic interaction with abiotics is possible. The big leaves option implies that an array of leaves can be considered by the model but the lowest number is one.

Value	Meaning
Off	No salt calculations will be made.
On	Salinity will be considered.

Value	Meaning
Off	No snow accumulation nor melting will be considered.
On	Snow will be simulated by a sub model for snow accumulation, melting, heat conduction and energy exchange between snow and atmosphere.

Value	Meaning
off	No water vapour flows will be calculated between soil layers.
Only SoilVapourflow	Water vapour flows between adjacent soil layers will result from gradients in vapour pressure and the diffusion constant. The diffusion coefficient is adjusted because of deviations from diffusion in free air by use of the parameter DvapTortuosity.
Soil- and SnowVapourflow	Vapour flows are also calculated for the snow.
Only SnowVapourflow	Vapour flows are only calculated for the snow.

Value	Meaning
Off	No water flows will be calculated. A constant soil water content is assumed according to selected initial conditions.
On	Water flows between adjacent soil layers will be calculated.