Geography Reference
In-Depth Information
Fig. 6.3 The spatial distributions classification of the five major LULC-categories in the ERB
for the data of LANDSAT-TM acquired in May-1987
more details and information within the image but with the decreased possibility of
spectral separation between the features of interest (indicating that, spectral sep-
aration increases or decreases according to the used sensor and its techniques).
One of the negatives reflected by the classifying of each scene alone was the
emergence of separating borders between two neighbouring scenes after the mo-
saicing-process, which meant there was no continuity in representing the preva-
lence of features and classes naturally and spatially. This problem was limited by
use of a ''majority-filter''.
LANDSAT-TM-May-1987 data. This coverage was one of two coverages (in
addition to the LANDSAT-TM-May-2007 coverage) which were used to produce
a map of the change detection which has occurred in the past 20 years, through the
application of the post-classification change detection approach. During the clas-
sification of both coverages into the five basic classes (Fig. 6.3 ), there was a
mistake in classifying some areas of rain-fed cultivations as natural plant lands,
because the most rain-fed plantations have a low density vegetal biomass, making
them close to that which characterizes natural plants.
There was an increase in ratio of classification (over-classification) of the
artificial surfaces specifically in volcano areas and Lake Al-Asad's banks, and also
in some bare areas. The reason for this is that as is the case with the MSS, the
negation or the lack of success ratio of radiometric correction imbued the radio-
metric properties of the same land features distributed in the several satellite
scenes (i.e., those that construct the mosaic-scene), with similar or at least enough
approximate compatible value/s. So, to overcome this problem, it was necessary to
classify each image alone and then create mosaic-processes of scenes of the
automated classification results.
Search WWH ::




Custom Search