You could perhaps try some agrohydrological model instead.
For instance, the Dutch SWAP model can account on such drainage-effect issues, as well as the capillary rising supplies. The model uses the Feddes function to simulate such effects.
We have made some SWAP simulations of water-excess and capillary rising effects on maize actual ET. The reference is:
Utset, A., Martínez-Cob, A., Farré, I., Cavero, J. 2006. Simulating the effects of extreme dry and wet years on the water use of flooding-irrigated maize in a Mediterranean landplane. Agric. Water Manag. 85:77-84.
However, this approach needs to be improved, in order to include such effects on the final yields.
Besides, I think DSSAT modeller are working on this as well.


Regards,

Angel Utset
ITACyL
47071-VALLADOLID
Telf. +34 983 317396 Fax.+34 983 414 780
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-----Mensaje original-----
De: DSSAT - Crop Models and Applications [mailto:[log in to unmask]] En nombre de Thorp, Kelly
Enviado el: viernes, 11 de abril de 2008 18:42
Para: [log in to unmask]
Asunto: yield response to excess soil water

Dear List:



The Agricultural Drainage Management Systems (ADMS) Task Force is keenly
interested in a model that is able to simulate the yield reduction that
may possibly occur from excess soil water stress when using drainage
water management technology in the Midwest U.S. (i.e. raising the water
table during the growing season by managing the depth of the subsurface
drain outlet to reduce nitrate loss).  I am aware that previous versions
of DSSAT (i.e. version 3.5) could not simulate yield loss due to excess
water stress.  What is the status of this in the newer versions, and how
does it work for the corn and soybean models in particular??



Also, what is the status of the model's ability to simulate artificial
subsurface drainage, and how feasible would it be to get the model to
simulate drainage water management (i.e. simulating the tile outlet at
different depths throughout the growing season??)



Thanks,

Kelly



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Kelly Robert Thorp, Ph.D.

Research Agricultural Engineer

USDA-ARS

U.S. Arid-Land Agricultural Research Center

21881 North Cardon Lane

Maricopa, AZ  85238

520-316-6375 (phone)

520-316-6330 (fax)

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