Dear Ali,
I can't imagine that anybody has data at hand that could really be
useful for you.
Besides the shape of the root density profile that might vary to a
certain extent, it is definitely maximum rooting depth that should be
very responsive to water stress. Or do you consider unstressed
conditions? Then, you could simply calculate ET using FAO-56 or any
other appropriate method. However, if you have water stress conditions,
then both, rooting depth and stress, are correlated to a large extent.
Decrease maximum rooting depth in the model and water stress will
increase, and vice-versa. This is a dilemma which you cannot solve
easily.
(On the other hand, as it seems, you have all degrees of freedoms to
come up with results that will match your anticipations... :-) )
Best regards,
Rolf
P.S. Btw., 'Question' is not a very meaningful subject for a list-server
message.
============================================
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 73-1916
Fax : 0049 228 73-1889
www.zef.de
www.khorezm.uni-bonn.de/
============================================
-----Original message-----
>
> Dear Colleagues,
>
> We need to simulate ET for tall fescue grass using HYDRUS model. Does
> anyone knows what a typical "root density profile" for this grass
looks
> like?
>
> Thank you very much in advance,
>
> Ali
>
> Ali M. Sadeghi, Soil Physicist
> Environmental Quality Laboratory
> USDA-ARS, BARC-West,B-007,R-211
> 10300 Baltimore Ave.
> Beltsville, MD 20705
> Phone:(301) 504-6693
> Fax: (301) 504-5048
> Email: [log in to unmask]
> http://www.barc.usda.gov/anri/eql/sadeghi.html
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