DSSAT Archives

DSSAT - Crop Models and Applications

DSSAT@LISTSERV.UGA.EDU

Options: Use Forum View

Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
"Boote,Kenneth J" <[log in to unmask]>
Reply To:
Boote,Kenneth J
Date:
Mon, 15 Dec 2008 16:20:17 -0500
Content-Type:
text/plain
Parts/Attachments:
text/plain (35 lines)
Anjum,

These are not errors, but are programmed in the CERES maize model.  But unfortunately, the DSSAT shell does not give enough advice on the reasons for these messages.  I recently did a series of late sowing date simulations for the state of Iowa where there is cold weather and freezing weather, and I checked into the code to see the causes for the messages.  For Iowa the causes were cold, but for your case (you could also have severe water stress or zero solar radiation days or bad weather file with "cold" temperatures).  The following were my discovered causes for the messages.

CERES-Maize has two types of model warnings about cold weather:
“Crop mature on day XXX due to slowed grain filling”
This is not a freeze per se, but early maturity is triggered when relative seed growth rate is less than 10% of “normal” for 5 consecutive days.  This can be caused by light, drought, or temperature effect on RUE.  In this study, it was not drought (no water stress was allowed), and was mostly temperature-driven.

“Crop failure growth program terminated”
 This one is related to cold temperature on photosynthesis, and  is triggered if there have been 7 consecutive days when CARBO (photosynthesis) is less than .001 before plant matures due to temperature, water or nitrogen stress.  Again, these simulations were done with no water or N stresses.  The Tb for CARBO is 6.2C (mean temperature) and the lowest mean temperature (Topt) for CARBO is 16.5C.

In your particular case, you need to consider what your limiting resource is.  If you have severe drought, then water limitation could be the cause for the terminations (less than 10% of normal seed growth or 7 consecutive dates when CARBO is less than 0.001).  You may even have a weather file with errors (bad temperature records or zero solar radiation), which would do the same thing.

Good luck with it.
Ken Boote
Professor, Univ. of Florida


________________________________________
From: DSSAT - Crop Models and Applications [[log in to unmask]] On Behalf Of muhammad anjum iqbal [[log in to unmask]]
Sent: Monday, December 15, 2008 4:55 AM
To: [log in to unmask]
Subject: PLEASE NEED HELP... CROP FAILURE GROWTH PROGRAMME TERMINATED.

Dear Sir,
I am working on Deficit irrigation and using DSSAT4.0.1. Model was calibrated and validated nicely .Now I am going long term simulations from 1976 ...2007.
During long term simulation in some years I received a mesage*.. Crop failure growth programme Terminated...
But the model RUNS successfully.
This type of ERROR not mentioned in th manuals.
PLEASE GUIDE ME WHY IT HAPPENES...
....................................................................
THANKS
KIND REGARDS
ANJUM

ATOM RSS1 RSS2