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Impacts of Intensive Agriculture and Crop Rotation on Soil F

Posted: Mon Nov 04, 2002 7:29 am
by "Michael Bean"
Don Seville and I worked with Prof. Steve Taff from the University of Minnesota and Peter Buessler
from the Minnesota Department of Natural Resources to create a simulation that lets users test
policies and see the impact on farms and the local environment. The simulation is called AgLand.

You can read about the simulation at:
http://www.forio.com/facevalue20010531.htm#agland

There are four types of soil in AgLand, typical of many midwestern farmland soils. Soil quality
(represented by the high- or low-productivity indicator), tillage method, and field slope establish
yield conditions. If soil loss through cropping exceeds soil building (the default setting is three
tons per acre per year), field topsoil depth diminishes. At first, this has little or no effect on
yield, but as topsoil depth decreases to a critical minimum level, yields increasingly diminish. The
limit of this decrease is roughly half of the original base yield. By contrast, soil loss and soil
building continue at the same rate regardless of topsoil depth. The simulation converts tons of soil
to soil depth. Generation rate and maximum depth are set in the model. Initial topsoil volume in
AgLand corresponds to fewer than six inches in depth (typical for the midwestern US). One change
from reality-- AgLand fields are much more sensitive to soil loss than are most real fields.

An overview of the simulation is available at:
http://www.extension.umn.edu/agland/overview.html

Best regards, Michael
_______________________________________
Forio Business Simulations
mbean@forio.com
www.forio.com