Web application I-FARM with GIS tool
I-FARM (http://i-farmtools.org)
is a free web-based simulation model for farmers and decision makers. It
evaluates changes in farm management in terms of environmental and economic
effects. Result pages include product mass balances, inputs (seed, fertilizers,
livestock feeds and manures), required labor and fuels, expected soil erosion,
soil carbon sequestration, nutrient balances, subsidies, and farm income.
Important program inputs are soil type and hill slope per field, and weather
station location. To accommodate the program user a GIS-application has been
added to I-FARM. The GIS application has layers that include roads, streams,
railroads, elevation data (30 m raster DEM), imagery (ESRI on-line), soil
databases (ISPAID and SSURGO), and weather station and ethanol plant locations.
The GIS-module has been designed as a Microsoft .NET application (program
language C#) that displays the maps through ArcGIS 9.2 Server technology. The
user identifies farm fields by drawing polygons. The program then looks-up the
dominant soil type and closest weather station location and calculates the
average hill slope and field aspect, and field area. These field attributes are
written in a SQL Server database table. Then I-FARM, which has been developed in
another language (ASP VBScript), reads the field attributes from the SQL
database and uses them in the simulations. CLIGEN 100-year generated weather
data have been incorporated for all 2,500 US weather stations. I-FARM applied
the USDA-NRCS SSURGO soil database, which is organized by county. SSURGO data
are currently available in I-FARM for 38 states. Spatially explicit SSURGO
shape-files have been converted into raster-files to accommodate calculations,
currently for 4 states (Iowa, New York, Pennsylvania, and Vermont).
Ed van Ouwerkerk
Department of Agricultural and Biosystems Engineering
Iowa State University
phone 515-294-9127
I-FARM http://i-farmtools.org/i-farm