In: Wagner W., Székely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010, IAPRS, Yol. XXXVIII, Part 7B
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5.2.2. Estuaries
5.2.3. Sea and ocean
4.3. LAND COVER CLASSIFICATION USING
REMOTE SENSING TECHNIQUES
Everything on earth is changing with time. Land cover
map can be a powerful tool to compare the changes of an
area over time. It is impossible to cover a large area in short
time through manual survey but with remote sensing (land
cover map) it is an easier task.
With land cover map it can be revealed how mach
area of cities of Albania is using for what purpose, what are
the pattern of land use change over time etc. which will
help the policy makers to take necessary measure to ensure
sound physical environment of the city etc.
Land cover maps constitute necessary tools for
development planning and management of the territory.
Furthermore, land cover maps depicting the current reality
are essential in countries where, due to political changes,
rapid dynamic phenomena have taken place, resulting in a
complete restructuring of the agricultural and other sectors,
as in the case of Albania.
For optimal use, land cover maps should be in digital
format, which allows easy updating, and associated with a
GIS including other information such as soil units, erosion
features and provincial/municipal boundaries. The resulting
database is an essential tool for decision-making in land
management.
But, before the creation of land cover map, it is
necessary to have land cover classification (LCCS) (fig.
Fig. 3.3.1. The place of LCCS in methodological approach
of land cover maps creation
Today, land cover classification based in use of
satellite image data. The operational availability of high-
resolution satellite imagery, namely Landsat TM, SPOT,
Soyouz, ERS-SAR, RADARSAT and others, opens up new
possibilities for investigating and monitoring natural
resources.
Satellite imagery is recorded in various
wavelengths, visible and non-visible, which provide
accurate information on ground conditions. Each object
has unique and different characteristics of reflection or
emission in different environment. An object and it’s
environmental condition can be identified using reflected or
emitted electromagnetic radiation from that object.
The use of satellite image is popular world wide
but its application is limited in Albania. However a land
cover classification in our study is done. The classes were:
1. Vegetation; 2. Built-up Area; 3. River/Deep Water; 4.
Shallow Water; 5. Open Ground
LANDSAT TM image was used for this study
(table 3.3.1).
able 3.3.1:
Wavelength and a
pplication of LANDSAT TM bands
Band
Wavelength
(Pm)
Application
1
0.45-0.52
Coastal water mapping, soil
vegetation differentiation,
deciduous, coniferous
differentiation
2
0.52- 0.60
Green reflectance by healthy
vegetation, excellent for
pollution studies.
3
0.63-0.69
Chlorophyll absorption for
plant species differentiation
identifies contrast
between the vegetation
classes.
4
0.76-0.90
High reflectance for the
vegetation, urban areas less
reflective than the
vegetation. Soil-crop and
land-water contrasts are
emphasized.
5
1.55-1.75
Important for the crop
identification, crop water
content and soil moisture
content.
6
10.4-12.5
Hydro thermal mapping
7
2.08-2.35
Plant heat stress
The properties of the image were:
• Image Sensor: LANDSAT TM
• Image Format: BIL
• Number of Lines: 2185
• Number of Pixels per Line: 1441
• Spatial Resolution: Band 1-5, 7 30m x 30m and band 6
120mX120m
• Spectral Resolution: 7 BANDS (1, 2, 3, 4, 5, 6, 7)
Geocoding Wizard of ER Mapper was used for
image registration and for registration, rectification and
image classification the source image was converted from
ERDAS LAN format to ER Mapper ERS format. The
parameters of geocoding were:
Geocoding type: Polynomial
Polynomial order: Linear
GCP picking method: A pre registered image of the
area.
The procedure of image enhancement makes it easy
to identify and select ROIs (Region of Interest). In this
study linear stretching and filter operations was performed
for image enhancement.