Hi,


DSSAT crop models are extremely sensitive to the choice of LL, DULL, and SAT
and these values must be specified correctly.  Recently we evaluated (
Wading through a swamp of complete confusion: how to choose a method for
estimating soil water retention parameters for crop models, European Journal
of Agronomy, Volume 18, Issues 1-2, December 2002, Pages 75-105 A. J.
Gijsman, S. S. Jagtap and J. W. Jones) several pedo-transfer functions and
found numerous problems with them.  Since then, we have a new methodology
which promises to be 100 to 500% better than any existing methods.  This
paper is in the publication process now.

In the mean time, if you would like, you can send me your basic soil texture
information (clay, sand, silt, organic matter, bulk density etc)  and I will
give you LL, and DULL values.  You can then compare these to your existing
estimates.

Thanks,



Dr. Shrikant Jagtap
Ag & Biological Engineering
261 Rogers Hall, PO BOX 110570
University of Florida
Gainesville, FL 32611
Tel: 352 392 1864 Ext. 261
Tel: 352 379 0698 (Home)
Fax: 352 392 8476
web:  http:\\www.agen.ufl.edu\~sjagtap\ssj\
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