Dear Jean:

Should the model have an interaction with the groundwater, say shallow water
table/perched water table, the soil water dynamics could be influenced, i.e.
capillary rise could be an additional source of water in the soil column.  But
the soil column in DSSAT is assumed as well drained.

what you can do i think is to have some sensitivity analysis on soil depth, you
can extend your soil profile adding some soil layers with similar property as
the lower most layer available in your data.  this might give you some
insights.  but some published studies on the use of DSSAT have used 60 cm soil
depth in their simulations.

but if you're only interested with the effect of CO2 change without considering
water as constraint in crop growth, the spatial variability of weather over the
area is important.

Regards,

Amor Ines
AIT-Thailand

Quoting Jean-Philippe Brassard <[log in to unmask]>:

> Dear DSSAT users,
>
> I'm using the DSSAT suit of crop models to evaluate the impacts of
> CO2-induced climate change on agricultural yields in the province of
> Quebec,
> Canada.
>
> because I'm trying to evaluate the impacts on crop yields for all of
> Quebec's agricultural region, I'm not working on some specific sites.
> As
> such, I have very general soil data for every region.
>
> My problem is that the only analysis of the soils caracteristics that
> was
> done for the whole of quebec's agricultural territory did not go deeper
> than
> 60cm. Hence, my soil profiles contain only 3 layers and are 60cm deep.
>
> I wanted to know if that would affect the final simulated yields in a
> significant manner and, if so, if there is any way to solve this
> problem?
>
> thank you for your help,
> Sincerely,
>
> Jean-Philippe Brassard
> Departement de Geographie
> Universite de Montreal
>
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