1. General Model Information

Name: Nitrogen Tillage - Residue Management model

Acronym: NTRM

Main medium: aquatic+terrestrial
Main subject: hydrology, biogeochemistry , agriculture
Organization level: landscape
Type of model: ordinary differential equations, partial differential equations
Main application:
Keywords: hydrology, nitrogen, leaching, soil, plant, management, climate, GIS



Shaffer, M.J.


NTRM (Nitrogen Tillage - Residue Management) model is a simulation model examining soil-plant interactions. The model is used to determine soil management strategies and the effect of climate change on crop yields and nitrate leaching (Shaffer and Pierce, 1982). The model combines basic process equations for water flow, solute transport, plant and root growth, tillage effects, climate interactions, nutrient transformations, soil chemical processing and soil temperature.

The model requires soil properties, daily weather data and management options as input. The model provides tabular graphs containing a range of information on plant growth, water and solute transport and soils temperatures as output.

The model uses daily time steps and examines field/plot to regional spatial scales using GIS.

Author of the abstract:


II. Technical Information

II.1 Executables:

Operating System(s): DOS

II.2 Source-code:

Programming Language(s): FORTRAN

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

Soil properties, weather data (daily), and management inputs. Model Input Data Source: Databases such as NCDC, SCS Soils 5, and Pedon one site data from field plots.

III.2.2 Output

IV. References

Shaffer, M.J., and F.J. Pierce. 1982. Nitrogen-tillage-residue management (NTRM) model: user'smanual. Res. Rep. USDA-ARS, St. Paul, Minnesota.

Shaffer, M.J. 1985. Simulation model for soil erosion-productivity relationships. J.Environ. Qual. 14(1):144-150.

V. Further information in the World-Wide-Web

NTRM at the CIESIN database

VI. Additional remarks

Global change implications:NTRM has been used to study long-termeffects of soil and environmental conditions on crop yields (Shaffer, 1985). Model predictions of long-term crop yields were consistent with actualdata. However, model short-term yield predictions did not perform well when compared to actual data. This model would thus be useful for globalchange research on the effects of soil conditions, especially soil erosion,on long-term crop yields.
Author : CIESIN
Last review of this document by: Thu Sep 18 1997
Status of the document:
last modified by
Joachim Benz Tue Feb 25 18:27:00 CET 2003

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