Behnam,

Yes, this is acceptable for simulating sprinkler irrigation, although a deeper depth say to 30 cm and a threshold of 50% is more reasonable.  Irrigating at 50% threshold in top 30 cm zone will irrigate to prevent drought stress most of the time (via automatic irrigation).

The DSSAT is not set up for scheduling irrigating at different growth stages, in the simulation control section.  You would need to do that with direct entry of dates and amounts in the irrigation application section.

Ken Boote

-----Original Message-----
From: DSSAT - Crop Models and Applications [mailto:[log in to unmask]] On Behalf Of Behnam Ababaei
Sent: Saturday, March 17, 2012 10:22 AM
To: [log in to unmask]
Subject: Simulation of Sprinkle Irrigation with Automatic Irrigation Settings

Dear DSSAT users,

I'd like to simulate a situation similar to Sprinkle Irrigation. I want to
do this using Automatic Irrigation. I tested different Depth and Threshold
values. The best settings seems to be 10 cm depth and 60% of available water
(50 cm and 50% is used to simulate Surface Irrigation with smaller number of
irrigation applications in relation to Sprinkle Irrigation). Is this a
proper setting to simulate Sprinkle Irrigation? Is there any suggestion?
Also, I'd like to know if I can define different settings for different
growth stages? How can I define the growth stages in the main DSSAT input
file? What is the meaning of "GS000"?



Sincerely Yours.

Behnam Ababaei, Ph.D. Candidate,

Department of Irrigation & Reclamation Engineering,

Faculty of Agricultural Engineering & Technology,
College of Agriculture & Natural Resources,

University of Tehran, Karaj, Iran, 31587-77871.

P.O. Box: 4111.