The model creates a file, SIM.DIR, which contains the file names of four output files and the titles of the treatments simulated as well as a file name for seasonal observation data. These file names can later be picked up by the graphics program for graphical display of outputs (see User's Guide for details). If a file name was listed for a fifth output file in the experiment directory file (WHEXP.DIR) for risk analysis or multiple-year applications, then the name of this file will also appear in SIM.DIR. If no file name for this (generally OUT5.WH) was entered in WHEXP.DIR then SIM.DIR will not contain this file name.

The five output files for any experiment contain different classes of data. The nature of the outputs in each of these files is described below:

File Number Name Description

1 OUT1.WH Summary output file describing management inputs, crop development, simulated yield, yield components and comparisons with observations.

2 OUT2.WH Simulated crop variables vs. time.

3 OUT3.WH Summary weather data and simulated water balance variables vs. time.

4 OUT4.WH Simulated soil and plant N variables vs. time.

5* OUT5.WH Summary data for use in risk analysis.

*Optional output file

In File 1, a one line summary output is written at the end of each growth stage. In Files 2, 3, and 4 output is written to file after every seven days of simulation. Provision has been made within the model to allow the user to interactively select a different output frequency for each of Files 2, 3 and 4 if desired. This is described in more detail in the User's Guide.

OUTPUT FILE HEADER INFORMATION

Each of the output files commences with a header containing the title used for the simulation run, the identification codes for the institute, and site where the experiment being simulated was conducted. Titles for the experiment, the treatment within the experiment, treatment number and the year the experiment was planted are also printed. The header also identifies the weather data set used, the soil type and the variety used in the experiment. Identical headers are printed in each of the four files for each treatment simulated.

SUMMARY OUTPUT FILE

When running the model the summary output appears on the screen as the crop is being simulated. Output File 1 is a record of what appears on the screen. After listing the file header information, the latitude, sowing depth and plant population and the genetic constants for the variety simulated are listed. This information is followed by irrigation information if the crop was irrigated. This lists the dates and amounts of each irrigation applied. This information is followed by soil characteristics including: a name for the soil pedon (PEDON), the soil albedo, the upper limit of Stage 1 soil evaporation (U), soil water conductivity (SWCON), and runoff curve number. For each layer in the profile the following information is then displayed: the lower and upper depth boundaries of the soil layer, the lower limit of plant extractable water (LO LIM), the drained upper limit (UP LIM), the soil water content at saturation (SAT SW), the plant extractable soil water (EXT SW), initial soil water content (IN SW), the rooting preference factor (WR), the extractable nitrate (NO3) and ammonium (NH4) in units of mg N/kg soil. All water contents are expressed as volume fractions. Below the layer information, totals for the whole profile where appropriate are displayed. For the water contents these totals are expressed as cm of water and for the nitrogen concentrations the totals are expressed in units of kg N/ha.

If the nitrogen balance is being simulated, the model next lists fertilizer information. For each application, the day of the year, the amount (kg elemental N/ha), the depth of incorporation, and the fertilizer source are listed.

All of the display described so far refers to an "echo" of the inputs required for the simulation run. When running the model this echo can be switched off so that only the summary information generated by the simulation as described below is displayed on the screen. Regardless of whether the echo is displayed on the screen or not it is written to the output file. After the echo, the program prints a message indicating the day simulation began.

Once simulation has commenced, one line of summary information is displayed at the end of each growth stage. These data include the day of the year, the accumulated thermal time since planting (CDTT), the description of the ontogenetic stage, the above-ground biomass (BIOM,g/m2), leaf area index (LAI), nitrogen uptake in the above-ground vegetative biomass (NUPTK,kg N/ha), the concentration of N in the above-ground vegetative biomass (N%,%), the cumulative evapotranspiration (CET,mm), the cumulative precipitation (RAIN,mm) and plant extractable soil water in the soil profile (PESW). RAIN and CET are accumulated from the beginning of the simulation until germination. After germination RAIN and CET are both initialized to zero, their values then represent the cumulative ET and precipitation occurring after germination. When the simulation reaches the terminal spikelet stage of growth (T SPKLT) the number of days the crop underwent vernalization (VE DAYS) is printed. At the end of ear growth, the number of ears (EARS) per square meter is also printed. At maturity the grain yield in kg/ha and bushels/acre, the grains per square meter (GPSM) and the dry weight of a single kernel (mg) are printed.

Next the model prints a comparison table of predicted and observed values of: the date of anthesis,the maturity date, the grain yield (kg/ha), the kernel weight (mg), the number of grains per square meter, the number of grains per ear, the maximum leaf area index, final above-ground biomass (kg/ha), the weight of straw (kg/ha), the nitrogen concentration in the grain (%), the total above-ground nitrogen uptake (kg N/ha), the straw N uptake (kg N/ha), and the grain N uptake (kg N/ha). When running the model an option exists to bypass displaying this table. If the menus were accessed during the model run, a message is printed indicating the comparison of predicted and observed yield may not be valid.

The model next prints a summary of the water and nitrogen stresses which occurred during each of the growth stages of the crop. CSD1 and CNSD1 refer to the cumulative stress indices for water and nitrogen respectively for photosynthesis. CSD2 and CNSD2 refer to the water and nitrogen (respectively) cumulative stress indices for extension growth processes. When these indices have a value of unity it implies the maximum amount of stress occurred during that growth stage and a zero value implies that no stress occurred during that period (Fig. 6.1)

Fig. 6.1

CROP GROWTH OUTPUT FILE

This file can be displayed when a model run has been completed. The model prints the header information at the beginning of the file and the growth information is written in subroutine OUTGR. The interval at which output is written to this file has a default value of seven days but this may be changed by accessing the output frequency menu when running the model. The following information is written to the file: day of the year, the cumulative thermal time elapsed since the beginning of the growth stage (SDTT, day degrees), above-ground biomass (BIO, g/m2), tillers per meter square (TPSM), leaf area index (LAI), root weight (ROOT, g/plant), stem weight (STEM, g/plant), grain weight (GRAIN ,g/plant), leaf weight (LEAF, g/plant), root depth (RTD, cm), plant top fraction (PTF), and root length density (RLV, cm root/cm3 soil) in layers 1, 3 and 5 in the profile. Fig. 6.2 is an example of the printed output from OUT2.WH.

SOIL WATER OUTPUT FILE

This file (Fig. 6.3) can be displayed when a model run has been completed. The model prints the header information at the beginning of the file. This file is written in subroutine OUTWA. The interval at which output is written to this file has a default value of seven days but this may be changed by accessing the output frequency menu when running the model. The following information is written to the file: day of the year, plant transpiration (EP,mm), evapotranspiration (ET,mm), potential ET (EO,mm), solar radiation (SR,MJ/m2), maximum temperature (MAX, oC), minimum temperature (MIN,oC), total precipitation over the interval (PREC,mm), the volumetric soil water content in each of the top five layers (SW1-SW5) and the total plant extractable soil water in the soil profile (PESW,cm).

Fig. 6.2

Fig. 6.3

SOIL AND PLANT NITROGEN OUTPUT FILE

This file (Fig. 6.4) can be displayed when a model run has been completed. The model prints the header information described previously at the beginning of the file. This file is written in subroutine OUTNU. The interval at which output is written to this file has a default value of seven days but this may be changed by accessing the output frequency menu when running the model. The following information is written to the file: day of the year, plant tops N concentration (%), N deficiency index (NFAC), total N uptake by above ground plant parts (TOT N UPTK, kg N/ha), N uptake into grain (GRAIN UPTK, kg N/ha), soil concentrations of nitrate in the upper five soil layers (ug N/g soil), and soil concentrations of ammonium in the upper three soil layers (ug N/g soil).

Fig. 6.4

OUTPUT FILE 5 (OUT5.WH)

This file will only be created when a name is listed in the experiment directory file. The file contains one line of summary information for each year of simulation. This file is compatible with the strategy evaluation program of IBSNATs Decision Support System for Agrotechnology Transfer. The file contains the following entries:

ENTRY INTERPRETATION

Crop Code This will always be WH:

A-M Days Number of days from anthesis to physiological maturity

E-M Days Number of days from emergence to physiological maturity

NLOSS Nitrogen lost from the profile (kg N/ha) by denitrification and leaching (nitrate moving through a layer at 1 meter depth is deemed lost for this purpose)

NIT STRS 3 Nitrogen stress index for growth stage 3

NIT STRS 5 Nitrogen stress index for growth stage 5

NUPTK Aboveground crop nitrogen uptake (kg N/ha)

NIRR Number of irrigations made to the crop

WAT STRS 1 Water stress index for growth stage 1

WAT STRS 5 Water stress index for growth stage 5

CET Cumulative evapotranspiration (mm) since emergence

RAIN Cumulative rainfall (mm) since emergence

BIOMASS Aboveground crop biomass (Tonnes/ha)

YIELD Grain Yield (Tonnes/ha)

PLANTS Plant population (plants/sq meter)

NFT Number of fertilizer applications made

NRATE Total amount of fertilizer N added (kg N/ha)

TITLE Treatment title