Appendix A — User defined output

SWAP allows users to define a set of output variables to be written to a file, enabling all results to be collected in a single file. If activated (swcsv > 0), a list of variables should be specified in inlist_csv as presented in Tip A.1. These variables can be time-series (Section A.1) and/or time-depth-series (Section A.2). All possible options are presented in the sections below.

Tip A.1: Example of user defined output in main *.swp file. 
* Part 4: Output files
...

* Specific CSV output file with timeseries (default: no)
 SWCSV = 1    ! Switch, output of variables to be specified
              ! 0 = No csv output
              ! 1 = Regular csv output
              ! 2 = Regular csv output + output of simulation characteristics
              ! 3 = Binary csv output + output of simulation characteristics

 INLIST_CSV = 'GWL,RAIN,RUNOFF,WC,H[-10.0:-30.0]'

This will result in csv-files which can be directly loaded by EXCEL1. The general name of the output file is specified in the main input file *.swp using outfil. The specified name of the output file is followed by ‘_output.csv’. SWAP will overwrite existing output files if they have the same name. This can result in an error in case of a rerun since EXCEL will lock the file while it is in use. Make sure to close the file in EXCEL before rerunning SWAP.

A.1 Time-series

Variables that involve water balances are presented in Table A.1 and Table A.2. The variables mentioned in Table A.1 represent integrals over the total soil column, if applicable.

Table A.1: List of possible variables for detailed water balance for total soil column. All variables are the sum over a given time interval, except for the model states, which are given at the end of the time interval. Note that any fluxes or storage related to macropores is not included in this water balance, except in DSTOR and BALDEV. See Table A.5.
Variable Explanation Unit
RAIN Rainfall cm
SNOW Snowfall cm
IRRIG Irrigation cm
RUNON Runon cm
RUNOFF Runoff cm
TPOT Potential crop transpiration cm
TACT Actual crop transpiration cm
EPOT Potential soil evaporation cm
EACT Actual soil evaporation cm
EPD Evaporation from a ponding layer cm
EIC Evaporation of intercepted water from canopy cm
ESUBLIM Sublimated snow cm
SSDI Total subsurface drip irrigation cm
DRN Net total drainage cm
BOT Net flow across bottom boundary cm
WTOT Water storage in soil matrix (excluding macropores) cm
SNOW_VOL Water storage as snow cm
PD_VOL Water storage as ponding layer cm
IC_VOL Water storage on canopy cm
DSTOR Change in water storage cm
BALDEV Water balance deviation cm

The user can select all these variables at once using the alias watbal. In case of using an alias, variables in the model output will automatically be filtered if a certain process is not activated. For example if no snow is simulated (swsnow = 0), no model output will be generated for snow, Esublim and SNOW_VOL. There are some miscellaneous parameters available for output which are not standard output when using alias watbal. These are listed in Table A.8.

It is possible to create a simplified water balance for a subregion of the soil column. A subregion is provided either as depths or compartment numbers between square brackets […], see Table A.2. For example [0.0:-30.0] (depth; floating point, negative) or [1:25] (compartment numbers; integer, positive). Any number of subregions may be entered (semicolon separated), e.g., SR_WTOT[0.0:-30.0;-30.0:-60.0;-60.0:-90.0].

All variables related to subregions can be selected by using alias subreg_min (only net terms of the water balance) and subreg_all. Square brackets should be added to the aliases in the same way as for an individual variable.

Table A.2: List of possible variables for simplified water balance for subregion of soil column. All variables are the sum over a given time interval, except for the model states, which are given at the end of the time interval.
Variable Explanation Unit
SR_TOP[...] Net inflow of water at top of subregion cm
SR_TOP_IN[...] Inflow of water at top of subregion cm
SR_TOP_OUT[...] Outflow of water at top of subregion cm
SR_RWU[...] Transpiration from subregion cm
SR_SSDI[...] Subsurface drip irrigation into subregion cm
SR_DRN[...] Net drainage water from subregion cm
SR_DRN_IN[...] Inflow via drainage into subregion cm
SR_DRN_OUT[...] Outflow via drainage from subregion cm
SR_BOT[...] Net inflow of water at bottom of subregion cm
SR_BOT_IN[...] Inflow of water at bottom of subregion cm
SR_BOT_OUT[...] Outflow of water at bottom of subregion cm
SR_WTOT[...] Water content in subregion cm

Variables with respect to the simulation of evapotranspiration are presented in Table A.3. The reduction of transpiration can be caused by too dry, too wet, too saline or too cold conditions, see variables tredxxx. Use alias etterms to select all (active) variables. Note that some variables appear both in this alias, and in the alias watbal. However, if both are chosen, variables will only be printed once.

Table A.3: List of possible variables for evapotranspiration and reduction of transpiration. All flux variables are the sum over a given time interval. Reduction is given as average reduction factor (1=no reduction) over a given time interval.
Variable Explanation Unit
Evapotranspiration
TPOT Potential crop transpiration cm
TACT Actual crop transpiration cm
EPOT Potential soil evaporation cm
EACT Actual soil evaporation cm
EPD Evaporation from a ponding layer cm
EIC Crop interception cm
ESUBLIM Sublimated snow cm
Reduction of transpiration
TREDDRY Reduction due to drought stress -
TREDWET Reduction due to oxygen stress (too wet) -
TREDSOL Reduction due to salinity stress -
TREDFRS Reduction due to frost stress -

Output of drainage fluxes can be specified for each drainage system defined. Using alias drain_all provides an overview of the drainage terms per drainage pathway, aggregated over the soil column, as presented in Table A.4.

Table A.4: List of possible variables for drainage. All variables are the sum over a given time interval, aggregated over the soil column. Negative values indicate infiltration. Even though MPDRN_1 is connected to one of the drainage systems (say, number X), its flux is not added to the output of DRAINAGE nor DRAINAGE_X.
Variable Explanation Unit
DRN Net total drainage, excluding rapid drainage through macropores cm
DRN_1 Net drainage through system 1 cm
DRN_2 Net drainage through system 2 cm
DRN_3 Net drainage through system 3 cm
DRN_4 Net drainage through system 4 cm
DRN_5 Net drainage through system 5 cm
MP_DRN_1 Rapid drainage out of macropores of domain 1 cm

Variables involving macropores that are integrated over the soil column (if applicable) are presented in Table A.5. Use alias macropore to select all variables of the Main Bypass (domain 1) and Internal Catchment (domain 2).

Table A.5: List of possible variables for macropores, integrated over the soil column (if applicable). All variables are the sum over a given time interval, except for the model states, which are given at the end of the time interval.
Variable Explanation Unit
Main Bypass (domain 1)
MP_TOP_1 Lateral overland flow plus vertical inflow at top of macropore zone domain 1 cm
MP_INF_1 Infiltration from (perched) saturated matrix into macropore of domain 1 cm
MP_EXF_1 Exfiltration from macropore into matrix of domain 1 cm
MP_DRN_1 Rapid drainage out of macropores of domain 1 cm
MP_WVOL_1 Water storage in macropore domain 1 cm
MP_BALDEV_1 Error in water balance of macropore domain 1 cm
MP_TVOL_1 Total macropore volume of domain 1 cm
MP_GWL_1 Water level in domain 1 cm+sl
Internal Catchment (domain 2)
MP_TOP_2 Lateral overland flow plus vertical inflow at top of macropore zone domain 2 cm
MP_INF_2 Infiltration from (perched) saturated matrix into macropore of domain 2 cm
MP_EXF_2 Exfiltration from macropore into matrix of domain 2 cm
MP_WVOL_2 Water storage in macropore domain 2 cm
MP_BALDEV_2 Error in water balance of macropore domain 2 cm
MP_TVOL_2 Total macropore volume of domain 2 cm
Combined volumes
MP_VOLDYN Dynamic volume of all macropores cm
MP_SUBSID Vertical shrinkage of all macropores cm

Variables that involve crop growth are presented in Table A.6. We distinguish a simple crop growth module (or static crop growth module; with a prescribed crop development) and two dynamic crop growth modules (WOFOST and GRASS) in which leaf photosynthesis and crop growth is actually simulated. Use alias crop to select all general variables, alias wofost to select all WOFOST variables and alias grass to select all GRASS variables.

Table A.6: List of possible variables for crop growth. All variables are given at the end of the time interval, except for the model rates, which are given as sum over the output period.
Variable Explanation Unit
CROP
TSUM Cumulative temperature sum from start of growing season of the crop °C
DVS Crop development stage -
CH Crop height cm
CF Crop factor -
LAIPOT Leaf area index for potential run m2 m-2
LAI Leaf area index m2 m-2
RDPOT Rooting depth for potential run cm
RD Rooting depth cm
VCOVER Fraction of soil covered by vegetation m2 m-2
WOFOST
PGASSTPOT Potential assimilation rate after management factor, potential crop growth kgch ha-1
PGASST Potential assimilation rate after management factor, actual crop growth kgch ha-1
GASSTPOT Assimilation rate after nitrogen stress and max. yield, potential crop growth kgch ha-1
GASST Assimilation rate after nitrogen stress and max. yield, actual crop growth kgch ha-1
MRESTPOT Maintenance respiration potential growth kgch ha-1
MREST Maintenance respiration actual growth kgch ha-1
PWDM Dry weight of dead and living plant organs potential growth kg ha-1
WDM Dry weight of dead and living plant organs kg ha-1
PWSO Dry weight of storage organ potential growth kg ha-1
WSO Dry weight of storage organ kg ha-1
PWLV Dry weight of living plant leaves potential growth kg ha-1
WLV Dry weight of living plant leaves kg ha-1
PWST Dry weight of living plant stem potential growth kg ha-1
WST Dry weight of living plant stem kg ha-1
PWRT Dry weight of living plant root potential growth kg ha-1
WRT Dry weight of living plant root kg ha-1
PDWLV Dry weight of dead plant leaves potential growth kg ha-1
DWLV Dry weight of dead plant leaves kg ha-1
PDWST Dry weight of dead plant stem potential growth kg ha-1
DWST Dry weight of dead plant stem kg ha-1
PDWRT Dry weight of dead plant roots potential growth kg ha-1
DWRT Dry weight of plant roots kg ha-1
PTWLV Dry weight of dead and living plant leaves potential growth kg ha-1
TWLV Dry weight of dead and living plant leaves kg ha-1
PTWST Dry weight of dead and living plant stem potential growth kg ha-1
TWST Dry weight of dead and living plant stem kg ha-1
PTWRT Dry weight of dead and living plant root potential growth kg ha-1
TWRT Dry weight of dead and living plant root kg ha-1
GRASS
PHRVDM Cumulative dry weight of harvested grass potential growth kg ha-1
HRVDM Cumulative dry weight of harvested grass kg ha-1
PLOSSDM Total loss of potential harvest during grazing or mowing kg ha-1
LOSSDM Total loss of actual harvest during grazing or mowing kg ha-1
ICUTPOT Cutting number potential growth -
ICUT Cutting number -
TCUTPOT Duration of cutting number potential growth d
TCUT Duration of cutting number d

Variables that involve solute transport are presented in Table A.7. Use alias solbal to select all variables involving solute transport.

Table A.7: List of possible variables for solute transport. All variables are the sum over a given time interval, except for the model states, which are given at the end of the time interval.
Variable Explanation Unit
S_RAIN Amount of solutes in precipitation g cm-2
S_IRRIG Amount of solutes in irrigation water g cm-2
S_BOT Amount of solutes passed through the soil column bottom g cm-2
S_DRN Total amount of solutes transported via drainage systems g cm-2
S_DEC Amount of solute decomposition g cm-2
S_UPT Amount of solutes extracted by plant roots g cm-2
S_STOT Total amount of solutes in soil column g cm-2
S_BALDEV Solute balance deviation for current balance period g cm-2
S_DSTOR Change in solute storage g cm-2

In addition to the mentioned variables, several miscellaneous variables can be requested. These are presented in Table A.8.

Table A.8: List of other variables. All variables are the sum over a given time interval, except for the model states, which are given at the end of the time interval.
Variable Explanation Unit
RAIN_NET Net rainfall cm
IRRIG_NET Net irrigation cm
TOP_IN Total inflow of water at top of soil column cm
TOP_OUT Total outflow of water at top of soil column cm
TOP Net inflow of water at top of soil column cm
BOT_IN Total inflow of water at bottom of soil column cm
BOT_OUT Total outflow of water at bottom of soil column cm
GWL Groundwater level cm+sl
PGWL Perched groundwater table cm+sl
PGWL_BOT Bottom of perched groundwater table cm+sl
PP Root water potential cm
PL Leaf water potential cm
T_ATM Average daily temperature of current day °C
T_TOP Temperature at top of the soil column °C
T_BOT Temperature at bottom of the soil column °C
MP_TOPD_1 Inflow into top of macropore domain 1 due to direct inflow cm
MP_TOPL_1 Inflow into top of macropore domain 1 due to lateral inflow cm
MP_TOPD_2 Inflow into top of macropore domain 2 due to direct inflow cm
MP_TOPL_2 Inflow into top of macropore domain 2 due to lateral inflow cm

A.2 Time-depth-series

In case of time-depth series results for all of the soil compartments are generated by default. Optionally output can be generated for a region of the soil column by specifying a depth range, see tz_z1_z2, or by specifying a depth or range of depths between square bracket (see Tip A.1 for an example). Time-depth-series are given one column for each requested depth. Note that printing all soil compartments in case of many compartments and for a large number of time-depth-series may result in rather large output files.

When specifying depths between square brackets, they must be provided for each time-depth variable individually, either as actual depths or as compartment numbers. For example, specifying H[0.0:-30.0;-90.0] (depth; floating point, negative) gives all pressure heads between 0.0 and -30.0 cm depth, as well as the pressure head at -90.0 cm depth. Specifying WC[1;3:5;10] (compartment numbers; integer, positive) gives the water content in nodes 1, 3 to 5 and node 10. If no square brackets are given for a time-depth variable, output is given for either all model nodes, or the nodes within the range tz_z1_z2, if specified.

When requesting depths, SWAP selects the representative node and provides output for this node. If, for instance, a depth of -2.0 cm is requested, and the size of the nodes is 5 cm, SWAP returns the requested variable at a depth of -2.5 cm. The actual output depth is printed in the header of the csv-file and may therefore deviate somewhat from the requested depth. Note that vertical fluxes between model compartments (Q, S_QSOL, MPC_Q_1 and MPC_Q_2) are given at the top of a model cell rather than at the central node of the cell. This is reflected in the printed output depth.

An overview of all output available as time-depth-series is given in Table A.9. Alias macroporecp can be used to display all of the listed macropore variables. Similar depth specifications can be used for the alias as for the single time-depth variables.

Table A.9: List of possible time-depth variables. All variables are the sum over a given time interval at a given depth, except for the model states, which are given at the end of the time interval at a given depth.
Variable Explanation Unit
Water states
H[...] Pressure head cm
WC[...] Volumetric water content cm3 cm-3
Water rates
Q[...] Vertical flux between matrix compartments cm
QSSDI[...] Subsurface drip irrigation flux cm
QDRN[...] Total net drainage cm
QDRN_1[...] Net drainage system 1 cm
QDRN_2[...] Net drainage system 2 cm
QDRN_3[...] Net drainage system 3 cm
QDRN_4[...] Net drainage system 4 cm
QDRN_5[...] Net drainage system 5 cm
RWU[...] Root water uptake cm
Crop
PRWU[...] Potential root water uptake cm
RRWU[...] Reduction in water extraction prior to compensation cm
RDENS[...] Relative root distribution -
LRV[...] Root length density distribution cm cm-3
HROOT[...] Pressure head at the root-soil interface cm
MROOT[...] Matrix flux head at the root-soil interface cm2 d-1
MFLUX[...] Actual matric flux potential cm2 d-1
WROOT[...] Root weight kg ha-1
O2TOP[...] Oxygen concentration at top of compartment kg m-3
Soil temperature and soil properties
T[...] Soil temperature °C
HEACAP[...] Soil heat capacity J m-3 K-1
HEACON[...] Soil heat conductivity W m-1 K-1
K[...] Hydraulic conductivity cm d-1
C[...] Differential soil moisture capacity cm-1
Solute
S_CONC[....] Solute concentration g cm-3 water
S_CONCADS[...] Adsorbed solute content g cm-3
S_QSOL[...] Vertical solute flux between matrix compartments g cm-2
Macropore
MPC_Q_1[...] Vertical flux between macropore compartments, domain 1 cm
MPC_QEXC_1[...] Exchange flux between macropore and matrix, domain 1 cm
MPC_QDRN_1[...] Rapid drainage from macropore, domain 1 cm
MPC_WVOL_1[...] water volume in macropore, domain 1 cm
MPC_TVOL_1[...] Pore volume in macropore, domain 1 cm
MPC_WET_1[...] Time averaged fraction of macropore wall wet, domain 1 -
MPC_Q_2[...] Vertical flux between macropore compartments, domain 2 cm
MPC_QEXC_2[...] Exchange flux between macropore and matrix, domain 2 cm
MPC_WVOL_2[...] water volume in macropore, domain 2 cm
MPC_TVOL_2[...] Pore volume in macropore, domain 2 cm
MPC_WET_2[...] Time averaged fraction of macropore wall wet, domain 2 -
MPC_VOLDYN[...] Dynamic macropore volume cm
MPC_SUBSID[...] Subsidence of soil matrix cm

  1. The csv-output uses ‘,’ as a list separator, ‘.’ as a decimal symbol and ‘YYYY-MM-DD’ as date format. When loading model results into EXCEL, these symbols and date-format are sometimes not recognized which is caused by default settings your operating system. You can change default settings at ‘Region’ settings (“Change date, time, or number formats”) on WINDOWS.↩︎