Arjan

Thanks for your significant points. Just a technical note for now. In your
response to Ken Boote's email you said:

"Though I have never seen the code for the water utility of the DSSAT shell,
I am pretty sure that it is Ritchie et al. (1987). I disagree that this is
much the same as Ritchie 1999, which generalizes much more by giving every
soil, besides the very sandy ones, a water-holding capacity of 0.132
cm3/cm3, only varying with organic-carbon concentration"

One should note that whenever the term "water holding capacity" is used it
means DUL (or field capacity) not the available water for plants. In
Ritchie 1999, the available water (besides very sandy soils and besides
compacted soils) not the water holding capacity was assumed 0.132 cm3/cm3.

Yours,

Ayman

Ayman Suleiman, PhD
Research Associate
Civil and Environmental Engineering Dept.
7B DANA Engineering Building
Bucknell University
Lewisburg, PA 17837
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