Model setup

Exercise objective:

·    Preparing data files for parametization

Exercise:

Ex-VI.1. Start up the Shell FSEWinRunOnly. Open project C:\COURSE\PARAM\ORYZAWin. Read CONTROL.DAT and verify its contents:

FILEIT = 'C:\COURSE\PARAM\MANAGE.TST'   ! Experimental data

FILEI1 = 'C:\COURSE\PARAM\IR72.D92'     ! Crop data

FILEIR = 'C:\COURSE\PARAM\RERUNS.DAT'   ! Rerun file

Examine the experimental data file MANAGE.TST. Verify that the runmode is in experiment mode and that the production and nitrogen environments are potential. Compare the settings of the management parameters with the information provided in Box VI.1, and compare the measured variables at the end of the file with the data given in Box VI.2. Check the weather data file CHINA2.987. Open the file IR72.D92 and check that this is the standard crop data file for the rice cultivar IR72. Now open the rerun file and verify its contents:

FILEI1 = 'C:\COURSE\PARAM\JD305.DAT'   ! Crop data JD305 test

A rerun will be made using the crop data in the file JD305.DAT. This file has exactly the same contents as that of IR72.D92 and was created by just copying and renaming the file IR72.D92. This file will be adjusted stepwise for the variety Jin Dao 305 during the process of model calibration.

Run ORYZA2000, open the data output file Run_0 and find the dates for panicle initiation (at DVS=0.65), flowering (at DVS=1) and maturity (at DVS=2). Compare these with the observed values (in MANAGE.TST and in Box VI.1) and comment on the differences. Next, make graphs of simulated and observed LAI, WAGT, WSO, WLVG and any other variable of your choice versus time. Note that Run_0 and Run_1 produce exactly the same results, since they both use the same crop parameters. Comment on the difference between simulated and observed variables.

It is clear that the parameter values for IR72 (in the Philippines) are not suitable for JD305 (in China)! Using the development rates for IR72, the simulated dates of panicle initiation, flowering and maturity are much earlier than the actual ones as given in Box VI.1 and in the experimental data file MANAGE.TST. This means that the variety Jin Dao 305 has a longer growth duration than cultivar IR72. This also explains the strange shape of the measured LAI and biomass curves in Figure VI.1: ORYZA2000 stopped simulation at development stage 2 (on day 249), which was even 2 days before the actual flowering date (251) of the real crop. Therefore, all measured values after flowering have not been plotted in the figures. The measured data for WSO are even completely absent in Figure VI.1d. The first step in calibration is thus to find the correct development rates.

For reference during the exercises, the original crop data file IR72.D92 is given in Appendix 5 and the file JD305.DAT after calibration in Appendix 7.

Figure VI.1a. Simulated and measured leaf area index (LAI; -); cv. JD305, Beijing, 1987; without calibration.

Figure VI.1b. Simulated and measured dry weights (kg ha-1) of green leaves (WLVG); cv. JD305, Beijing, 1987; without calibration.

Figure VI.1c. Simulated and measured dry weights (kg ha-1) of total above-ground biomass (WAGT); cv. JD305, Beijing, 1987; without calibration.

Figure VI.1d. Simulated and measured dry weights (kg ha-1) of storage organs (WSO); cv. JD305, Beijing, 1987; without calibration.