Demonstrating intermediate visual analysis and pattern recognition using a processing model in ERDAS Imagine and ArcGIS. Training sites were used to train algorithm (trees, water, houses/urban ISA areas) to classify image to impervious surface area (ISA) then re-projected data and overlay in other geographic data.
Visual analysis and pattern recognition using gis and remote sensing techniques presentation skills
1. A GIS-based approach to
characterize urbanization at the
sub-watershed scale
in Mill Creek,OH
Jaleann M. Matos-Mc
Clurg
2. Talk Outline
Purpose
Data and Scales of Analysis
Study Area
Research Framework
Research Questions
Data Sources
GIS Data Manipulation
Maps
Metadata Discussion
LULC Reclassification Strategy
More Maps
Remote Sensing & GIS
Future Work
3. Purpose
To characterize urbanization growth with
two landscape-based indicators:
(1) Population density (people/mi2
)
(2) Land-use/Land-cover (LULC)
4. Data and Scales of Analysis
Sub-watershed scale
Population density by census tracts
Land-cover (County & Sub-watershed scale)
LULC- “crude classification” without user changes
LULC data – Reclassification*
LC change“stats” & display*
* Sub-watershed scale only
5.
6. Research Framework
Goal: Characterize urbanization.
Increase of average population at sub-
watershed scale since 1920’s from cities
and townships.
LULC changes could trigger disturbance of
hydrological flows and pathways.
Temporal growth of impervious surface
areas (ISAs) as urbanization expands.
7. Research Questions
(1) What is the spatial-temporal dynamic of
urbanization at the sub-watershed and county
scales?
(2) Does a population density or land-cover
based approach help describe urban change?
(3) How does the spatial-temporal
characterization of urbanization at the sub-
watershed scale relate to changes in the
hydrological flow regime? (Master Thesis Main RQ)
8. Data Sources
Census Tract Data (1970-2000)-Geolytics, Inc.
Land-use/Land-cover (LULC)
Data
USGS EROS Data Center (EDC)
Historical LULC derived from 1970’s and 1980’s
aerial photography.
National Land-cover Dataset (NLCD) derived from
early 1990’s using Landsat TM satellite images.
USGS EDC
NALC triplicates – Landsat MSS satellite data.
9. GIS Data Manipulation
Geo-processing
Operations
“Clipping”
Calculate
& Recalculate
Area using
Xtools
Export
Data to Excel
Import Utility 71
(.e00)
Arc Toolbox: Define
PCS and GCS
“if undefined”
Reproject Data
Raster Calculator
Operations
Attribute Data
Manipulation
& Use of
display “rules”
Vectorization
Add summarized
“stats” to layout
Spatial Analyst:Reclassify
12. Average population density within Mill Creek,OH
sub-watershed at multiple geographical
scales of analysis
0
1000
2000
3000
4000
5000
6000
1905 1925 1945 1965 1985 2005
Decennial Census Year
Populationdensity
(people/mi2
)
Cities & Townships
(estimated)
Sub-watershed-census
tracts
County (Butler & Hamilton)-
census tracts
Urban population density
threshold
13. County-level
Average population density by census tracts at the county level
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
1965 1970 1975 1980 1985 1990 1995 2000 2005
Decennial Census Year
Populationdensity(people/mi2)
061=Hamilton Co.
017=Butler Co.
Average (061& 017)
Urban population density threshold
14. County-level within sub-watershed
Average population density by census tracts at the watershed level
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
1965 1970 1975 1980 1985 1990 1995 2000 2005
Decennial Census Year
Populationdensity
(people/mi2)
061=Hamilton Co.
017=Butler Co.
Average (061 & 017)
Urban population density threshold
15.
16.
17. Metadata Discussion
Useful to get information about spatial data
in general.
For example …PCS, GCS, data quality,
intended applications, etc.
Often, LULC data has different LULC
classification schemes.
I compiled a “summary table” from LULC
and NLCD classification schemes.
26. Future Work
Sub-watershed Scale
Compare urban census tracts by LC code (reclassified)
and quantify their relative area.
Generate a LC map of change between 1970 & 1990.
Regional & Methodological Scale
Expand geographical area of analysis.
Develop a “Hybrid GIS-based Framework” that considers
simultaneously LC change and population density changes
to characterize urbanization.