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Expected
Use Macro
The expected-use
macro developed for IDRISI 32 is slightly different than the macro developed
for IDRISI for Windows 2.
The expected-use
macro for IDRISI 32 has 13 steps, and incorporates the "place holder"
capability offered by IDRISI 32. To operate the expected-use macro three
coverages are required, as well as a name for the resulting expected-use
coverage. The three coverages required are:
- A slope
map of the entire analysis area with slope values in percent. The slope
map is also utilized as the basis for the reference coordinates of the
resulting expected-use coverage.
- A water
sources coverage with livestock watering points given a value of 1.
- A pasture
polygon coverage for the individual pasture being analyzed, with the
pasture having a value of 1, and the rest of the area a value of 0.
Additionally
a customized palette named "expected use.smp" for displaying the expected-use
coverage is utilized. Wildland Solutions utilizes a palette with the following
values:
1. The
areas of concentrated use are given a value of 1 and shown as pink.
2. The areas of moderate use are given a value of 2 and shown as yellow.
3. The areas of light use are given a value of 3 and shown as blue.
4. The areas of slight use are given a value of 4 and shown as green.
5. The areas of incidental use are given a value of 5 and shown as gray.
The place
holders designed into the expected-use macro for IDRISI 32 are as follows:
- %1 is
the slope map coverage developed for the analysis area.
- %2 is
the water points coverage developed for the pasture being analyzed.
- %3 is
the polygon coverage developed for the pasture being analyzed.
- %4 is
the name assigned to the expected-use map that will be produced for
the pasture being analyzed.
Note:
To make the data more informative and easier to understand line 12 of
the macro reclasses each pixel into one of 5 expected use classes. The
breaking point between class1 (concentration area) and class 2 (moderate
use) is rather sensitive. If the class break point is established as 1.98,
the result is that moderate use is assigned to pixels that are more than
450 yards from water on slopes less than 6%. If the class break point
is established as 1.99, the result is that moderate use is assigned to
pixels that are more than 350 yards from water on slopes less than 6%.
If the class break point is established as 1.999, the result is that moderate
use is assigned to pixels that are more than 280 yards from water on slopes
less than 6%.
-----Expected-use
Macro for use with IDRISI 32-----
INITIAL X
PX-MWPT*1*1*0*1*%1
POINTRAS X %2*PX-MWPT*1
DISTANCE X PX-MWPT*PX-WTDS
INITIAL X PX-POLY*1*1*0*1*%1
POLYRAS X %3*PX-POLY
OVERLAY X 3*PX-WTDS*PX-POLY*PX-WTDC
FUZZY X 1*PX-WTDC*1*PX-WTDZ*200*200*200*3200
OVERLAY X 3*%1*PX-POLY*PX-SLPC
FUZZY X 1*PX-SLPC*1*PX-SLPZ*6*6*6*45
OVERLAY X 1*PX-WTDZ*PX-SLPZ*PX-SU
OVERLAY X 3*PX-SUT*PX-POLY*PX-SUIT
RECLASS X I*PX-SUIT*%4*2*1*1.99*2.02*2*1.7*1.99*3*1.35*1.7*4*1.05*1.35*5*0.0001*1.05*-9999
DISPLAY X n*%4*expected use*n
**Property
of Keith Guenther and Wildland Solutions
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