Dear Laura,

As Gerrit has said already, there is a tillage beta-version of DSSAT which
however needs some more final editing and checking (maybe Gerrit could
consider you as a beta-tester...).
The current version does not consider tillage, besides as far as I remember,
speeding up soil organic matter decomposition for some fixed time after the
actual tillage event.
Also, a surface residue layer - though it can be simulated to decompose -
does not have any influence on the below soil nor on surface water runoff.
Thus, as Scott Staggenborg has already pointed out, right now DSSAT is, as
we say in German, "neither fish nor meat".

A couple of years back Jeff White and I had made an effort to check some of
the more well-known (crop) models for their ability to simulate conservation
agriculture, i.e. zero-tillage and residue management.
I could send you (and everybody else who is interested - just send me a
_private_ mail) the table with the final results of this study. This will
also soon be published in an article about modeling conservation agriculture
(using CropSyst) in Soil & Tillage Research.

Best regards,
Rolf Sommer

============================================
Dr. Rolf Sommer
ZEF, Center for Development Research
Department of Ecology and Resource Management
University of Bonn
Walter-Flex-Str. 3
53113 Bonn Germany
E-mail: [log in to unmask]
Tel.: 0049 228 73-4926
Fax : 0049 228 73-1889
www.zef.de
www.khorezm.uni-bonn.de/
============================================


> -----Original Message-----
> From: DSSAT - Crop Models and Applications
> [mailto:[log in to unmask]] On Behalf Of Laura Olivera
> Sent: Monday, August 14, 2006 15:42
> To: [log in to unmask]
> Subject: tillage and no tillage
>
> Dear all:
>
> I want to simulate, tillage and no tillage effect in differents soils,
> so
> the question is.... if I don't put anything in the XBuild file
> managment/tillage/tillage implement, the simulation model assume that
> this
> is ''no tillage''?
>
> Thanks!!
>
>
> Laura Olivera McAlister
> Agronomist Engineer
> Agro climatic and Information Systems (GRAS)
> INIA La Estanzuela
> Colonia, Uruguay
> Phone: (00598) 574 8000 ext. 1439
> Visit our web site: www.inia.org.uy/gras/