Dear Arantxa,
 
we also use version 3.1. - CO2 effects are not considered in this
version. Mass production (as a result of photosynthesis) is modeled
using the concept of radiation use efficiency, which seems to work
well under none-stressed conditions. - Crop water budget is simulated
on the basis of a simple soil water cascade model and the Priestly
Taylor equation that is basically an equilibrium ET-model using an
empirical correction factor. - Stomatal control of photosynthesis and
transpiration is considered by no means in version 3.1. In fact this
is a variable that is extremely difficult to estimate and I doubt
that there is  a model available that would simulate stomatal/canopy
conductance with sufficient accuracy.
 
A couple of weeks ago I asked for an update information on the latest
DSSAT version 3.5, but haven't received any answer so far.
You might have to contact the group directly using following URL
 
http://agrss.sherman.hawaii.edu/dssat/dssat/AddIbsna.htm
 
Good luck !
 
Regards,
Matthias
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Dr. Matthias Langensiepen
Environmental and Agricultural Engineer
 
Department of Crop Science
Faculty of Agriculture
University of Kiel
 
Olshausenstrasse 40
24118 Kiel
Germany
 
Tel. +49-431-880-4398
FAX  +49-431-880-1396
EMAIL [log in to unmask]
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