Embed Size (px)
Citation preview
How to Map How to Map Irrigated and Non-Irrigated Land Irrigated and Non-Irrigated Land
on the on the Eastern Snake Plane AquiferEastern Snake Plane Aquifer
Quickly, Easily, and WellQuickly, Easily, and Well
How to Map How to Map Irrigated and Non-Irrigated Land Irrigated and Non-Irrigated Land
on the on the Eastern Snake Plane AquiferEastern Snake Plane Aquifer
Quickly, Easily, and WellQuickly, Easily, and Well
Image Processing Bill Kramber Classification Editing Tony Morse CLU Editing Margie Wilkins
Outline
Intro
The Past
The Present
The Future of the Past
What, exactly, do you mean when you say, “Irrigation?”
Irrigated all year long? Irrigated once or twice? Sub-irrigation? Entire field or only part?
For now, if >75% of field irrigated on one date, then
“Irrigated”
The Past
1980 RASA classificationrasa80lcLandsat MSS57 meter pixelsPer point classifier with stratification
1992 BOR/IDWR classificationSnakelc921:40,000 scale photosSeveral classesDigitized
rasa80lc
1980 RASA
rasa80lc
snakelc92
Snake92cl
Point
Both rasa80lc and snakelc92 over mapped irrigated.
The Present Classification Scheme
1. Edit and correct CLU polygons
2. Run a 3-Phase Classifier1) Per Pixel using 3 dates of NDVI2) Overlay CLU polygons3) Aggregate pixels by CLU polygon
3. Manual Edit of Classification
4. Allan buys the beer
CLU??
A Bit About CLUUSDA/FSA Common Land UnitGenerally correspond to agricultural fieldsGenerated for federal crop support programsOnly the polygons are available – not attributesDone for all Idaho counties, but need some editing.
3-Dates of NDVI
Blue 6/20/2006 Green 7/22/2006 Red 8/7/2007
Cluster and Interpret spectral classes
Phase 1: Per Pixel Classifier
Per Pixel Classifier Output
Phase 2: Overlay of CLU PolygonsPolygon is “Irrigated” if polygon > 75% irrigated pixels
Phase 3: Aggregation by CLU PolygonInitial Classification
Before Editing
After Editing
After Editing
Model Grid on final Classification
Point
NDVI/CLU classification is better than Snakelc92
The Future of the Past
Landsat Data Archive
2000
1990
1986
1984 MSS
Was it irrigated in 1992?
1992 2006
Unfinished Business
Who wants to do it?
Accuracy Evaluation
Snake River near Hagerman
