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MONITORING THE GROWTH OF SETTLEMENTS IN ILORIN, NIGERIA 
(A GIS AND REMOTE SENSING APPROACH) 
Zubair Ayodeji Opeyemi (Bsc, Msc) 
National Space Research and Development Agency, Abuja-Nigeria 
- azubair@nasrda.net,opemorenikeji@yahoo.com 
KEYWORDS: Remote Sensing, GIS, Supervised Classification, Built-up, Change, Growth, Landsat, Settlement 
ABSTRACT 
This paper examines the use of GIS and Remote Sensing in monitoring settlement (built-up) growth in Ilorin between 1972, and 2001 
so as to detect the changes that has taken place in this class between these periods. Landsat data for three epochs were used in the 
study. Supervised classification was carried out to identify five land use/cover types with particular emphasis on settlement. 
Subsequently, an attempt was made at projecting the observed growth in the next 14 years. In achieving this, Land Consumption 
Rate and Land Absorption Coefficient were introduced to aid in the quantitative assessment of the change. The result of the work 
shows a rapid growth in built-up land between 1972 and 1986 while the periods between 1986 and 2001 witnessed a reduction in this 
growth. It was also observed that change by 2015 may likely follow the trend in 1986/2001.An attempt was also made to suggest 
possible ways to use the information contained therein optimally. 
1. INTRODUCTION 
Studies have shown that there remain only few landscapes on 
the Earth that is still in their natural state. Due to anthropogenic 
activities, the Earth surface is being significantly altered in 
some manner and man’s presence on the Earth and his use of 
land has had a profound effect upon the natural environment 
thus resulting into an accelerated growth in settlement 
expansion. 
Land is becoming a scarce resource due to immense agricultural 
and demographic pressure. Hence, information on settlement 
growth i.e. consumption of new land with each unit of 
population growth and possibilities for their optimal use is 
essential for the selection, planning and implementation of land 
use schemes to meet the increasing demands for basic human 
needs and welfare. This information also assists in monitoring 
the dynamics of settlement expansion resulting out of changing 
demands of increasing population. Studies on settlement 
expansion have become a central component in current 
strategies for managing land as a resource and in monitoring 
environmental changes. 
Viewing the Earth from space is now very crucial to the 
understanding of the influence of man’s activities on the earth 
over time. In situations of rapid and often unrecorded growth in 
settlement, observations of the earth from space provide 
objective information of human utilization of the landscape. 
Over the past years, data from Earth sensing satellites has 
become vital in mapping the Earth’s features and infrastructures, 
managing natural resources and studying environmental change. 
The collection of remotely sensed data facilitates the synoptic 
analyses of Earth - system function, patterning, and change at 
local, regional and global scales over time. 
2. MOTIVATION 
Ilorin, the Kwara State, capital has witnessed remarkable 
expansion, growth and developmental activities such as 
building, road construction, deforestation and many other 
anthropogenic activities since its inception in 1967 just like 
many other state capitals in Nigeria. This has therefore resulted 
in increased land consumption and a modification and 
alterations in the status of her land use land cover over time 
without any detailed and comprehensive attempt (as provided 
by a Remote Sensing data and GIS) to evaluate this status as it 
changes over time with a view to detecting the rate at which 
land is being consumed and also make attempt to predict same 
and the possible changes that may occur in this status so that 
planners can have a basic tool for planning. It is therefore 
necessary for a study such as this to be carried out if Ilorin will 
avoid the associated problems of a growing and expanding city 
like many others in the world. 
Indeed, attempt has been made to document the growth of Ilorin 
in the past but that from an aerial photography (Olorunfemi, 
1983). In recent times, the dynamics of Land use, particularly 
settlement expansion in the area requires a more powerful and 
sophisticated system such as provided by a GIS and Remote 
Sensing data which provides a general extensive synoptic 
coverage of large areas than area photography. 
3. AIM 
The aim of this study is to document the growth of Ilorin 
Township as obtained from satellite data and GIS between 1972 
and 2001 and also predict the pattern of growth in same over a 
given period. 
4. OVERVIEW 
This paper has its focus on growth in built up land (settlement) 
but attention was given to a general mapping of land use land 
cover of the study area. The resultant maps served as a basis for 
identifying growth in settlement and subsequently predicting 
same over a given period. Therefore, in the related works, 
attention will be given to change in land use and land cover in 
the study area since the product of each image classification is a