Hello, Marta
As excerpted from Volume 4, Chapter 1 of the DSSAT manuals,
SPECIFYING OBSERVED SOIL LAYER DATA FOR WINGRAF
The capability to graph simulated data using the same soil layers as those
used for
observed data was not documented in the WINGRAF chapter of DSSAT v3 (Chan et
al., 1994). The following is a description of the naming convention to be
used for
headers when setting up a file for measured time series data FILET. The
first letter of
the header specifies the variable measured. W is used for soil water
content, T is soil
temperature, N is soil nitrate and A is soil ammonium. The second space is
reserved
for values that specify the layer number in ascending order from the
surface. A maxi-
mum of 15 layers can be defined, using the hexadecimal numbering system. The
surface layer should be given a value of 1, the ninth layer should be given
a value of 9,
the tenth layer a value of A, etc. The third and fourth spaces together
specify the
thickness of the layer in centimeter. Below are several examples for all
four variables.
VARIABLE HEADER EXAMPLE EXPLANATION
Soil Water (W) W110 Surface layer, 10 cm thick
Soil Water (W) WA30 Tenth layer, 30 cm thick
Soil Water (W) WF25 Fifteenth layer, 25 cm thick
Soil Temperature (T) T220 Second layer, 20 cm thick
Soil Nitrate (N) N515 Fifth layer, 15 cm thick
Soil Ammonium (A) A115 Surface layer, 15 cm thick
When observed data are input using this naming convention for headers,
WINGRAF
will display the variable name preceded by an infinity symbol. The standard
soil
layers will also be displayed. To provide an appropriate comparison of
simulated and
observed data, WINGRAF recalculates the simulated output values provided by
the
model, which are for the standard soil layers, and graphs the resultant new
values for
the same soil layer as the observed data.
As an example, if you have measured soil water by depth at say 10,20,30, and
40 cm you can put the data in your PNT file similar to this example ..
@TRNO DATE W110 W210 W310 W410
1 86316 0.27 0.29 0.27 0.29
1 86328 0.23 0.28 0.24 0.28
1 86342 0.34 0.35 0.27 0.27
This shows layer 1 = 10 cm, 2 = 10 cm, and so on. Wingraf will then add
these depths to the graph menu (for water in this case) so that you directly
compare measured variables at the depth you measured them against model
output.
Hope this helps.
Cheers,
PW
Paul Wilkens
International Fertilizer Development Center
P.O. Box 2040
Muscle Shoals, Alabama 35630
(256) 381-6600 (Tel)
(256) 381-7408 (Fax)
[log in to unmask]
http://www.ifdc.org/
-----Original Message-----
From: Marta Graciela Vinocur [mailto:[log in to unmask]]
Sent: Monday, March 20, 2000 7:37 PM
To: [log in to unmask]
Subject: Question about .pnt files
Dear subscribers,
I have a question about how to do .PNT file which consider my own depth for
each soil layer and not the one that DSSAT provided. I measured soil water
content along the crop cycle considering the depth of each layer. When I
tried to do the .Pnt file with the measured values, I realized that the
depth considered for SW1D, SW2D, etc. are differents from my own depth. Is
there any way to solve this problem?
Thanking you in advance for your time and help, please receive my kindly
regards.
Sincerely
Marta Vinocur
Ing. Agr. M.Sc. Marta G. Vinocur
Facultad de Agronomía y Veterinaria
Universidad Nacional de Río Cuarto
Ruta Nac. 36 Km 601
X5804 BYA Río Cuarto, Córdoba
Argentina
Phone: 54 358 4676191
Fax: 54 358 4680280
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