1. General Model Information

Name: Torbert N Model

Acronym: TORBERT

Main medium: terrestrial
Main subject: biogeochemistry
Organization level: ecosystem
Type of model: ordinary differential equations
Main application:
Keywords: nitrogen cycle, plant-soil systems


Dr. Henry Allen Torbert
USDA-ARS Grassland, Soil, and Water Research Lab
808 East Blackland Road
Temple, TX 76502
Phone: 817-770-6503
Fax: 817-770-6561
email: a031ctemple@attmail.com


Dr. Henry Allen Torbert


The Torbert N Model is a computer simulation model designed to examine the interaction of nitrogen, carbon and water in small scale, plant-soil systems. It contains graphical user interfaces developed using Stella II on the Macintosh. This system is designed for three types of users: beginning students interested in learning about plant-soil interactions; intermediate students who want to explore the dynamics of state equations for plant-soil nitrogen interactions; and, researchers who wish to modify the existing state equations in order to test new hypotheses (Torbert, et al.).

The Torbert N Model contains several modules: fertilizer application, growing crop, atmospheric-N, soil organic matter and a groundwater N-input module. The model does require the user to provide input data values for soil N content (or fertilizer input), weather (temperature and rainfall), planting day, expected yield of corn and soil type. The weather generator component contains the Richardson weather simulator for crop management (WGEN) also discussed in this report.

Author of the abstract:


II. Technical Information

II.1 Executables:

Operating System(s):

II.2 Source-code:

Programming Language(s):

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

III.2.2 Output

IV. References

Torbert, H. A., M.G. Huck, R.G. Hoeft.Simulation of soil plant nitrogen interactions for educational purposes. Journal of Natural Resources and LifeScience Education. 23: (1) 35-42.

V. Further information in the World-Wide-Web

VI. Additional remarks

This model could be used for global change research program both as ateaching tool as well as a research tool. Because it is developed using apowerful and flexible modeling package (Stella II), this model can potentiallybe modified to test assumptions of the effect of global climate change onnitrogen cycling on small agricultural fields.

Last review of this document by: T. Gabele: 08. 07. 1997 -
Status of the document:
last modified by Tobias Gabele Wed Aug 21 21:44:51 CEST 2002

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