Hi,

I think there is no problem with the procedure.  My question is, how would
you proceed with the calibration? Manually?  The soil module in DSSAT i
think would automatically arrived at the soil parameters but in many cases
you need still to adjust them, some parameters are representation of the
hydraulic properties of the soil like the drained lower and upper limits,
drainage contant, among others.  I guess you have measured these in your
experiment.  You may proceed with your procedure but bear in mind that the
soil water dynmamics in DSSAT was assumed to be in a free-draining soil
column. So if your soil system is influenced by high water table or poor
lateral drainage, you might encounter some problems matching the simulated
and measured soil water.  I am not sure with the new version of DSSAT if
these are already included.

Best regards,

Amor

P.S. would anybody in the list is interested to a young, enthusiastic doctor
[PhD(Eng.)] to work in one of their projects? he's interested in sytems
integration especially to regional scale applications:-). same

----- Original Message -----
From: "Tesfalidet Ghebreab" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, October 26, 2002 1:48 AM
Subject: calibration of soil water balance


> Dear all,
>
> I want to calibrate the soill water balance model in DSSAT. I have got
> four months data of continuous soil water content measured in a tomato
> field trial with a datalogger and few measurements of leaf area index.
> In addition I have got measurements of reference evapotranspiration
> carried out with an ET- gauge. I wanted to use half of the data for
> calibration and the other half for testing the model. Is there any
> problem with this prodcedure?
>
> Thanking you for your time.
>
> Tesfalidet A. Ghebreab
> University of Natal
> Department of Agronomy
> Post bag X01
> Scottsville
> Pietermaritsburg, 3209
> South Africa
> e-mail [log in to unmask]
>