Since several people seem to be considering possible improvements to the
soil temperature model,I want to make one additional comment. I am working
on a modification of the soil-organic-matter and plant-residue module of
DSSAT, so as to make the model more suitable for low-input smallholder
systems commonly found in less-developed countries. If one does not apply
NPK, most or all nutrients have to come from residue and SOM decomposition.
Working with green-manure / cover crops, there often is a thick residue
layer on top of the soil, which gradually decomposes. Such a residue layer
clearly has an important effect on the soil temperature. Presently, DSSAT
does not consider a surface-deposited residue layer, so this effect is not
included. For a future version it would be useful to take this into
consideration.
 
 
Arjan Gijsman
Centro Internacional de Agricultura Tropical (CIAT)
Cali
Colombia