4. Spatial Analysis
The large degree of spatial analysis involved
in this task requires the use of a GIS.
The approach took to achieve the objectives
employs IDRISI's multi-criteria evaluation (MCE) module. Steps include the
establishment of factors for consideration, use of the fuzzy module to normalize
these factors thereby simplifying comparisons, weighting the factors relative
to each other and then input to the MCE module.
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Constraints ;
Factors ;
- Builtup_fuzz
- Contourslope
- Landuse_fuzz
- Road_fuzz
- Rocksoil_fuzz
|
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The small squares are
buildings. Slope ratio was not quite vital to build buildings. |
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The result of the MCE
operation shows that city expansion is already inside of the water safe
buffer zone which is determined by my hypothesis
.
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The Procedure
I. Constraints (BIGWATER)
1. Waterfuzz
Lighter orange color is closer
inside of my buffer zone meaning water danger zone
1) Identify watersheds from a DEM at varying thresholds.
2) In order to help you visualize how water would flow
through this watershed, create a map showing three dimensional relief for
this area.
3) Perform a reclass to define areas of surface water
to interpret the flow of surface water based upon a shaded relief map
4) Define a 10 meter buffer zone around all of the surface
water.
2.
Streamfuzz
Green spots indicate major
water channel location after buffering.
1) Perform a reclass to define area of surface stream
line to interpret the flow of surface stream
2) Define a 2 meter buffer zone around all of the surface stream
II. Factors (DEVELOPMENT)
3. Landfuzz
1) Reclass the land use data
Agricultureal area = 150
Open space & undevelopment area = 200
Watershed area = 255
2) Distance 100m buffer zone around all the land area
and
Fuzzy Sigmoidal (byte 0-255) Monotonically Decreasing
a=1 b=100
4.
Slopefuzz
, 5. Roadfuzz
, 6. Rockfuzz
, 7. Builtupfuzz
-----> The same process with Land_fuzz
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