of suitability in the same way as that of 
cumulative method. 
Once the suitability map was 
prepared based on the information on 
ground water, soil and slope; it was 
compared with land use map to see the 
correlation. Then the same layer was 
intersected with the land use map after 
assigning due weights to the land use 
classes. Both cumulative and multiplication 
methods were adopted and regrouped into 
suitability classes in the same way as 
earlier. Thus overall land suitability map 
GSSLUL was prepared. In both the 
analysis apart from the above layers, 
lineament map (fractures) was also 
considered. A buffer zone of 75m on 
either side of the lineament was generated 
and weight 3 was assigned to this zone and 
other area are ignored for assigning the 
weights. [Lineaments referred here are 
basically geological fractures which are 
weak zones in the country rock, and are 
found to have good ground water prospects. 
These lineaments are tapped through 
dug/bore wells and the water available are 
used for irrigation on either side. The 
approximate area which can be irrigated by 
the water drawn from the wells on these 
lineaments is around 75m on either side of 
the lineament. Since the ground water 
prospects of lineaments in the study area is 
moderate to good that means it can yield 
good but not very high quantity water, 
weight 3 was assigned]. This buffered 
lineament map was intersected with both 
GSSL and GSSLUL. 
Alur taluk comprises about 78 km? 
of wasteland (land  unutilised, under 
utilised, degraded, etc.), the majority of 
which are cultivable. Hence, suitability of 
wasteland with respect to soil, slope, 
ground water and lineament has been 
assessed. Wasteland map was integrated 
with ground water, slope, soil and 
lineament maps and the suitability of 
wasteland classes were assessed using the 
weights assigned earlier to different classes 
of these layers (Table-2). Later, using both 
cumulative and multiplication methods 
these were regrouped into seven suitability 
classes, as earlier. 
102 
5. RESULTS/DISCUSSION 
5.1 Land Suitability 
Layers generated by both 
multiplication and cumulation were 
compared to see which method gives the 
better result. It was found that layers 
generated by both the methods look almost 
alike except where tank and steep slope 
area are present (Table-3 and 4). The layer 
generated by multiplication showed 
unsuitable class more clearly. The reason 
is, in this method, if one class of a layer is 
unsuitable i.e. weight is zero, irrespective 
of corresponding classes in other layers 
having different weights, the effective 
weight becomes zero. Whereas in 
cumulative method, it is not the case. 
The layer GSSL was compared with 
the land use map to see the correlation 
between the land use classes and the 
suitability. It was found that good 
correlation exist between the land use and 
the suitability of land. The same is 
depicted in the Table-5. The analysis of 
GSSL showed that whole Alur taluk is 
more to most suitable (i.e. 49% more 
suitable and 32% most suitable). While 
about 14% of falling under class - suitable, 
only 0.56% and 0.05% are less and least 
suitable respectively (Table-3). 
Once the land use map was 
integrated with GSSL, it is observed that 
there is no significant change in suitability 
classes as such. This is because there is a 
good correlation between the current land 
use and the land suitability and the 
percentage-wise suitability classes are given 
in Table-3. The final land suitability map 
(GSSLUL) was carefully observed and 
the broad type of cultivation is suggested 
(Table-6). Surface waterbodies, barren 
rocks and steep slope areas are classified as 
unsuitable. The final land suitability map 
showed that valleys controlled by fractures 
are the highly suitable areas, valleys being 
the next best suitable class. 
5.2 Suitability of Wastelands 
In Alur taluk about 18.09% of the 
total geographical area falls under 
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