ArcInfo and satellite imagery are being used to map and monitor crop growth along the Colorado River between the Hoover Dam and the border of Mexico. All crop field boundaries and irrigation diverter boundaries are entered into the database by digitizing from orthorectified SPOT panchromatic scenes. Data are collected on the ground for a predetermined number of agricultural fields coincident with the Landsat Thematic Mapper flyover. Field data (i.e., crop type, height, percent cover, growth stage, soil moisture, etc.) are then entered into a fully attributed GIS database. A certain percentage of fields with ground data is reserved for accuracy assessment purposes. The remaining fields with attributed ground data are displayed over the Thematic Mapper imagery and supervised training signatures are taken for crop classification. Field boundaries in the GIS database are used for calculating field crop labels based on the pixel classification. Crop acreage is summarized by crop type within irrigation diverter boundaries for use in managing and allocating water from the Colorado River.
Mary Balogh
U.S. Dept. of Interior
Bureau of Reclamation
Lower Colorado Region
P.O. Box 61470
Boulder City, NV 89006-1470
Telephone: 702-293-8523
Fax: 702-293-8042
Robert Ottmann
U.S. Dept. of Interior
Bureau of Reclamation
Lower Colorado Region
P.O. Box 61470
Boulder City, NV 89006-1470
Ron Simms
U.S. Dept. of Interior
Bureau of Reclamation
Lower Colorado Region
P.O. Box 61470
Boulder City, NV 89006-1470
Bob Bathrick
Vaughan Landrum
Jeff Milliken