Estimating Animal Unit Months Using GIS and Remote Sensing, a Wyoming Case Study




Sun, Jeffrey A.

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Ranchers and range managers use a tool called an Animal Unit Month or AUM to estimate the number of animals a range can support for one month without over grazing. Currently, range managers have to go out in the field and cut, dry, and weigh the grasses to determine how much forage is on the range. Then they determine how many animals the range can support based on this field work. This research attempts to eliminate the field work by automating the AUM tool using remote sensed imagery and the NRCS SSURGO polygon data. A threshold of SAVI values will be implemented in the remote sensed imagery. The SSURGO data will be converted to a raster data set and categorized based on the forage amounts the NRCS gives for each type of Soil. Finally the imagery and the SSURGO data will be fed into ArcGIS 9’s Model Builder and a model will be built that will automatically calculate the total AUMs for the study area.



Grazing, Range management, Geographic information systems, Wyoming, Remote sensing


Sun, J. A. (2005). <i>Estimating animal unit months using GIS and remote sensing, a Wyoming case study</i> (Unpublished thesis). Texas State University-San Marcos, San Marcos, Texas.


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