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he LAND- 
> GT Mao. 
gita! £a: 
  
(a) The major landform units — the river Benue, the sand bars of the river bed, the sand islands, 
and to a lesser extent, the floodplains, were recognised by the computer, at least their outlines 
marked. They were all correctly classified. Fig. 2. 
(2) The large artificial features were recognised with differing accuracies by the classifier 
algorithms, 
These were notably settlements, airfield, burnt areas Fig. 2. 
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t 
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PS ean 
Fig 2: Digital map by Maximum Likelihood algorithm. Note the outlines of 
the major landforms: a = River Benue; b = Sand island: c = Sand Bar; d = 
Settlements while the physiographic — soil units are described by the pixels 
and quantified as on legend.