GIS FOR LAND SUITABILITY ASSESSMENT 
A.S. Padmavathy, K. Ganesha Raj, V. Jayaraman and M.G. Chandrasekhar 
National Natural Resources Management System 
Indian Space Research Organisation 
Antariksh Bhavan, New BEL Road, Bangalore-560 094, Karnataka, India 
ABSTRACT 
In a given area mainly the slope, soil (texture, depth), water availability (surface and 
ground), rainfall and climate decide the land suitability, apart from the human activity/needs. 
Land suitability of Alur taluk, Hassan district, Karnataka State, India was assessed by 
integrating various thematic maps generated from remote sensing and collateral data in a GIS 
environment. After assigning the due weights/ranks to the respective classes, the thematic 
maps were integrated by weighted aggregation method using ARC/INFO GIS package. 
Thematic maps - slope, soil, ground water and fracture were integrated to arrive at the 
suitability; the map thus obtained was compared with the land use map to find the correlation 
between the present land use and suitability and it was observed that good correlation exists. 
Further, land use map was integrated with the suitability map to refine/modify the suitability 
classes. The analysis showed that 81% of the area falls under more to most suitable 
categories, which are suitable for crops like paddy, sugarcane, dryland crops etc. Land 
suitability of Wastelands in the study area were also assessed and it was found that 92% of the 
wasteland area falls under suitable to more suitable categories and are suitable for dryland 
crops /agricultural plantation/forest plantation. The study showed that GIS is an effective tool 
for integrating various layers to assess the land suitability. 
1. INTRODUCTION maps generated in earlier study and several 
freshly generated maps were integrated 
using weighted aggregation methods. The 
ARC/INFO GIS package was used in the 
study (ESRI, 1989). 
Hilly areas have typical problems 
that generally hinder the developmental 
activities. Altitude, slope, erosion, 
deforestation, inadequate infrastructure 
facilities, flood, landslides and various 
other factors make the life of people living 
in a hilly region miserable. Many of the 
hill areas in our country are economically 
2. STUDY AREA 
The study area is Alur taluk (432 
km?) of Hassan district, Karnataka State, 
backward for these reasons. Remote India bounded by latitude N 12° 48'2" to 
sensing is an effective tool to assess the 13° 4'3" and longitude E. 75? 48'22" to 
condition, and also to plan the 76° 03'37". The net agricultural land is 
159.75 km? and the major crops grown are 
Paddy, Ragi, Jower and Pulses (Census 
Hand Book, 1984). Important commercial 
crops of the area are Coffee, Potato, 
Banana, Mango, Sugarcane, Cotton, etc. 
The irrigation facilities are very poor in this 
area and agricultural activity depends 
mainly on rain. The area receives good 
rain, but due to the hilly terrain runoff is 
high. The normal rainfall is around 100 cm 
annually. The total population is around 
79,000 (1991 census) with almost equal 
male and female population. The location 
map is given in Fig.1. 
developmental activities, of hilly areas 
(Gupta et al, 1992). Further, for 
integrating the spatial and  non-spatial 
information for assessing the suitability of 
the land, Geographical Information System 
(GIS) is a powerful technique (Berthold er 
al., 1992; Burrough, 1986; Gerardo ef al., 
1990: Hendrix and Price, 1986; 
Padmavathy et al., 1993; Richard, 1987; 
SAC, 1992; Toshiaki et al., 1989; Walsh et 
al., 1987; and Williams, 1985). In the 
present study, spatial data of Alur taluk, 
Hassan district, Karnataka was integrated to 
assess the land suitability. Various thematic 
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