Dear Juan,

I worked with Dr. Robert Caldwell to develop a multiple cropping system
model, CropSys, that incorporated all of the DSSAT crop models that were
available at the time (1991):

Caldwell, R.M. and Hansen, J.W., 1993. Simulation of multiple cropping
systems with CropSys. Pp. 397-412 in: Penning de Vries, F.W.T., Teng,
P., and Metselaar, K. (Eds.), Systems Approaches for Agricultural
Development, Vol. 2. Kluwer Academic Publishers, Dordrecht, The Netherlands.

We developed a hedgerow light interception and competition model that
would handle your intercrop.  I think Dr. Caldwell ([log in to unmask])
still maintains an educational version of CropSys.  Unfortunately, the
model was not maintained in the face of major modifications to the
component crop models.


Juan Pablo Monzon wrote:

> My name is Juan and I am trying to simulate the performances of a
> wheat/soybean intercrop.  The design of the intercrop (or relay
> intercrop) is 3:1 and has a distance of 75cm, I have 3 rows of wheat
> to 17,5cm of distance and 1 row of soy to 17,5cm of distance from the
> rows of wheat and again the same design.  The soy is sown 30 days
> before the harvest of the wheat.  Because of the design, the wheat
> fails to capture the totality of the radiation and the soy grows
> inside the wheat during 25-30 days until the wheat harvest and during
> this period the soy receives less radiation than the one that would
> receive it if sown alone. Any idea for this simulation is welcome.
> Greetings Juan Pablo Monzon
>

--
Dr. James W. Hansen
Associate Research Scientist - Agricultural Systems
International Research Institute for Climate Prediction
The Earth Institute at Columbia University
121 Monell Bldg., Lamont-Doherty Earth Observatory
PO Box 1000 / 61 Route 9W
Palisades, NY 10964-8000
USA

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