The message below was posted to the AGMODELS listserver, but information is
also very appropriate for the DSSAT listserver.  Sorry for cross posting is
you subscribe to both.
 
Gerrit
 
>As a follow up of my previous messages about databases structures for
>agricultural data, I would like to summarize the work we have done on the
>ICASA database structure.
>
>We divided our questions in two parts:
>A. description of the experimental setup;
>B. incorporation of measured data in the database.
>
>Is there anybody who can help with solving the problems described in
>this message?
>
>Thank you very much in advance for your help.
>
>Luca Bechini &
>Antonio Ruccia (mailto:[log in to unmask])
>
>
>----------------------------------------
>A. Description of the experimental setup
>----------------------------------------
>
>We read the official documentation from the DSSAT project and we then
>identified the meaning for most of the acronyms used for data headers (or
>data codes). The relations between the tables have been clarified by Barry
>Jacobson's Access version of the ICASA database.
>
>However:
>
>- several acronyms for data headers are still undocumented (point 1)
>- we do not know how to describe rotations (point 2).
>
>1. Acronyms not documented
>--------------------------
>
>The following list of acronyms is not documented in Tsuji et al. (1994). We
>tried to guess an explanation for some of them:
>
>FXCRD             X-coordinate of field corner ?
>FYCRD             Y-coordinate of field corner ?
>FELEV             field elevation (m asl)      ?
>FAREA             field area (m2)              ?
>FLSLL             field slope lenght           ?
>FLWR
>FLSLA
>
>ICRIP
>ICRID
>ICRAM
>ICRP
>ICRK
>ICR#
>ICWD
>
>PSPRL
>
>RMCD              a code related to residues management     ?
>
>CMCD              a code related to chemical application    ?
>CACD              a code related to chemical application    ?
>
>HBPC
>
>
>2. Rotations in DSSAT
>---------------------
>
>How are rotations treated in the DSSAT database structure? We realize
>that we should use the data codes named 'R', 'O' and 'C', but we do not
>know how.
>In the official documentation, they are described as:
>
>C        Crop component number (default = 1)
>O        Rotation component - option (default = 1)
>R        Rotation component - number (default = 1)
>
>The example files in the documentation do not provide any help in
>understanding their use.
>Also, in some of our experimental trials, two crops are grown during one
>year. This may add difficulties in describing the rotation in the database.
>
>----------------
>B. Measured data
>----------------
>
>We know that, besides the experimental setup, it is possible to include
>in the database measured data too.
>The official documentation suggests to use two types of files:
>- FILEP, for replicate data by plot
>- FILED, for replicate data by date
>
>However, several aspects of their use and format is unclear:
>
>1. which is their format?
>
>2. how to describe the relationship plot-treatment-replicate?
>
>3. how to describe measurements carried out at different dates?
>
>4. which data codes should be used to identify measured variables? The
>ones listed by Tsuji et al. (1994), in Appendix C ('Simulated and field
>data codes') are correct?
>
>5. in Appendix C, measurements of state variables for soil (e.g. soil water
>content, soil nitrate content) are considered at fixed depths. We would
>like to incorporate data measured at user-specified depths. Is there a way
>to do that?
>
>6. is it possible to describe the device used to obtain a given datum?
>
>For example, we measured both:
>
>- soil nitrate content and
>- nitrate concentration of soil solution extracted with ceramic porous
>cups.
>
>I think we can store the above data in two ways:
>
>- we may use two different variables for soil nitrate content and
>nitrate concentration of soil solution
>
>- or we may use the same variable (soil nitrate concentration), and add
>a code to indicate the device used to measure the variable (soil
>sample/porous cup).
>
>REFERENCES
>----------
>
>Tsuji, G., Uehara, G. and Balas, S. (Eds.), 1994. DSSAT version 3. Volume
>2, IBSNAT.
>
>=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=-=-=-=-=-=-=-=-=-=-=-=
>Luca Bechini, PhD       Agroecosystems modelling and Geostatistics
>Institute of Agronomy                         University of Milano
>tel. +39-02-70.600.164                       fax +39-02-70.633.243
>                   mailto:[log in to unmask]
>        http://imiucca.csi.unimi.it/~agra/iami/iami0.html
>=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=-=-=-=-=-=-=-=-=-=-=-=
>
 
 =======================================================================
Gerrit Hoogenboom
Associate Professor
Department of Biological and Agricultural Engineering
The University of Georgia
Griffin, Georgia 30223-1797, USA
 
Phone:  770-229-3438
Fax:    770-228-7218
E-mail:  [log in to unmask]
http://www.griffin.peachnet.edu/bae
http://www.bae.uga.edu/dept/faculty/gerrit/
 =======================================================================