This study presents the analysis of Akure urban land use change detection from remote imagery perspective. Efforts were made to examine the direction that the continuous expansion of the city tends towards since its inception as a state capital in 1976. Using Aerial Imagery Overlay (AIO), the pattern of land use changes in Akure and its environs were determined. This involves imageries interpolation and overlaying to determine the land use changes, direction, and extent of the expansion. Findings revealed unguided expansion in the growth of the city which affects the pattern of land uses within the city and, by extension, into the adjoining settlements. There were incompatible conversions in land uses and undue encroachment into green areas in the adjoining communities. The study suggests effective zoning strategy on unguided nature of urban development whose effects on land use are very prominent in the study area. Adequate monitoring by the Development Control Department and other stakeholders in urban planning is equally suggested to mitigate the incompatible land use changes in the area.
Land Use Land Cover Changes (LULCC) is urbanization induced, which has led to dramatic changes in land use practices [
Akure is not in any way going contrary to this prediction as the population has been more than triple of what it used to be before it became administrative headquarters of the state and local governments. For example, the population was just 71,106 in 1963; but with the influx of people into the town due to the state creation of 1976, the population rose to 239,124 in 1991 and 360,268 in 2006 [
Globally, land cover is often altered principally by direct human use such as agriculture and livestock raising, forest harvesting and management, urban and suburban construction and development. As submitted in several researches, hardly can we find any vegetation that has not been affected or altered by man in the world [
Several researches have shown that unplanned changes of land use due to urbanization have become a major problem [
Urban growth observation and management remains a major concern of Geographic Information System (GIS) and Remote Sensing (RS) applications. The duo provides historical vehicle to monitor and determine and evaluate long term changes in land use due to urbanization process. They have been proven to be effective means for extracting and processing varied resolutions of spatial information for monitoring urban growth. According to Cheng and Masser [
Land use changes arising from urbanization, housing development, agriculture, and deforestation are some of the contributing factors to land cover changes in Akure. These changes reflect on the population growth, land consumption rate, and local climate. Expansion of Akure has resulted not only in depletion of natural resources, but also in deterioration of the environment due to incompatible changes in land use pattern. Agriculturally productive land and forestland are being converted to residential and other private and public uses. Balogun et al. [
Akure is the capital of Ondo State as well as the headquarters of Akure South Local Government Area. Between 1976 and the present time, the city has experienced enormous growth and has developed independently of any spatial urban planning. This rapid growth became prominently noticed in the last two to three decades. As urbanized features extended farther from the central areas, lands populated by development are altered in significant ways. Since 1976 when the town became the state capital, there have been remarkable changes in its growth and development. Several developmental projects that brought transformation to the physical landscape of the city are very prominent. Oyinloye [
In order to mitigate the negative effects of the city’s growth and expansion, there is need for adequate programs and policies that can foster its sustainable development. The essence of this is to encourage and monitor development in a way that it will not damage the environment for the incoming generations. This can only be achieved by taking appropriate inventory of the available resources and planning for their present and future uses. It is on this premise, therefore, that the study is set to investigate the changes in pattern of land uses in Akure and its environs to suggest policies that can be used in combating its effects.
The study centers on Akure city and its immediate environments. Akure is a notable city in south-western Nigeria which became the capital of Ondo State on February 3, 1976. As shown in Figures
Ondo State in the national setting. Source: Department of Surveys, Federal Ministry of Works, Abuja (2014).
Ondo State and its 18 Local Government Areas. Source: Ondo State Ministry of Lands and Survey, Akure (2014).
Locational map of the study area in regional setting. Source: Ondo State Ministry of Lands and Survey, Akure (2014).
Data collection for this study was essentially through Aerial Imagery Overlay (AIO) with the aid of GIS, RS, and personal observations. Other sources include government ministries and establishments for historical milieu of the area as well as base maps and population data used for the study. Internet facilities were equally explored for relevant information. The study area has a total population of 476,159 in 2014 with a total land expanse of 125,212 ha. The main approach used in this study was mainly postclassification comparison analysis of satellite imageries of Akure obtained at three decadal variations between 1985 and 2014. This helps to examine variation in the change and to show the direction and extent of the growth from one period to the other. The studying period spans through three decades and is divided as follows: 1985–1994, 1995–2004, and 2005–2014. The land use for the study area is classified into four categories (as it physically applies to the study area). It includes the built-up area (involving residential, commercial, industrial, recreational, and educational land uses); thick vegetation (forested land areas); light vegetation (cultivated land areas); and the water bodies (rivers, streams, etc.).
As shown in Figure
Land use classification of Akure as of 1986. Source: Landsat 4 Thematic Mapper (TM) Imagery (1986).
The LULC classifications for the year 2002 are shown in Figure
Land use classification of Akure as of 2002. Source: Landsat 7 Enhanced Thematic Mapper (ETM+) Satellite Imagery (2002).
Figure
Land use classification of Akure as of 2007. Source: Landsat 7 Enhanced Thematic Mapper (ETM+) Satellite Imagery (2007).
In 2014, land use for built-up area (as shown in Figure
Land use classification of Akure as of 2014. Source: Landsat Operational Land Imager (OLI) Satellite Imagery (2014).
The implication of this analysis is expressed in the rate of urban expansion as illustrated by the trend of increase in the built-up area and light vegetation (cultivated land areas). The drastic reduction in the percentage of area covered by thick vegetation shows there was a phenomenal growth within the studying period. For instance, the built-up area increased by 22.3% between 1986 and 2014 and light vegetation (cultivated land areas) by 27.71%. This is likely to be the result of much encroachment into the thick vegetation and rocky and undulating land areas for the purpose of building construction, quarry, blasting and mining activities. Besides, the economic situation in the state around the time (especially in the ealier years of the millenium) was favourable for individuals, government, and various establishments to embark on massive developments. For example, in 2002, various projects were embarked upon as a consequence to the discovery that the state falls within the mineral endowed region, which resulted in the tremendous increase in the built-up areas. This accounted for the massive physical expansion of the region. Again, Akure gained a great influx of people seeking greener pastures being the state capital while the discovery of bitumen in the state attracted many investors and other immigrants within the studying period.
The LULC Classifications of Akure and the change detection analysis for the 1986–2002, 2002–2007, and 2007–2014 are presented in Table
LULC change detection analysis in Akure for the years 1986–2014.
The LULC | 2002–1986 | 2007–2002 | 2014–2007 | |||
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Difference in area (ha.) | Difference in area (%) | Difference in area (ha.) | Difference in area (%) | Difference in area (ha.) | Difference in area (%) | |
Built-up area | 14441 | 11.53 | 2160 | 1.73 | 11318 | 9.04 |
Thick veg. |
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Light veg. |
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Water body |
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Sources: Landsat Satellite Imageries (1986, 2002, 2007, and 2014).
LULC classification and change detection in Akure urban land use. Sources: Landsat Satellite Imageries (1986, 2002, 2007, and 2014).
The spatial pattern of sprawling in Akure over a period of three decades (1985–2014), as shown in Figures
The location of Federal University of Technology, Akure (FUTA), in the north-western part of the city has much influence in attracting huge population of people into the area. Most staff of the institution and students prefer to live close to it, thereby making the growth an institutional attraction. Currently, the growth around this institution has almost captured Ipinsa and Ibule (the two nearest settlements) as high percentage of students of the institution find cheaper accommodation there as well as cheaper lands for staff and people from Akure to build houses and hostel accommodation for students. This and other important developments that parade the city revealed significant difference in stages of expansion and land uses within the studying periods. These findings corroborate the work of Oyinloye [
The use of GIS to predict future expansion of the study area and possible changes in land uses was modeled with the aid of Markov Chain technique to guide policy makers in the management of land use activities in Akure and its environs. Adopting the 3.6% growth rate used in Oyinloye [
Urban built-up change detection analysis and predictive model to the year 2034. Sources: Landsat Satellite Imageries (1986, 2002, 2007, and 2014).
The study gives a clear indication of unguided expansion in the growth of Akure which affects the pattern of land uses in the city and its surrounding settlements. There were incompatible conversions of land uses and undue encroachment into green areas in the adjoining settlements due to favourable economic situation in the state around the period. In the early year of the millenium, Akure gained much influx of people being the state capital. Besides, the discovery of bitumen in the state attracted much investors and other immigrants in quest of greener pastures for job opportunities. Its administrative status and concentration of establishments were the key indices for this attraction. With this, the thick vegetation was massively encroached which consequently gave way to further developments and expansion from the city into various sorrounding communities. Also, the regional setting of Akure has naturally influenced the direction of the expansion. Findings revealed that the city spread out along the fairly flat areas of the north-western part of the city which appear to be more favourable to human settlements. Thus, the expansion first tends towards this direction before it began to diffuse to other areas.
Based on major findings in this study, it has become pertinent to put up some policy recommendations. In the first instance, the unguided nature of Akure urban development whose effects on land use pattern are well noticed in the study area needs adequate attention. The check on this should commence with land acquisition and allocation procedures for various uses so as to guide against incompatible land uses. It is therefore recommended that ministries in charge of land management should employ resourceful control measures over private and public land uses through effective zoning strategy. In view of this, the Development Control Department (DCD) in the Ministry of Urban Development and Physical Planning should be reinforced with strong tools to carry out their duties, particularly in the area of effective monitoring for sustainable development.
The existing land use in the study area is predominantly residential. Most of the buildings have aged and are in deplorable conditions. In some parts of the city, especially at the urban core, most of the old buildings are being removed and changed over to new ones. In the course of changing some of these buildings, the usages are always at variance with compatibility standard. They constitute nuisance rather than complementing the planning and environmental standards. In this regard, it is recommended that adequate monitoring be made by Development Control Department (DCD) and other stakeholders in urban planning, right from plan approval stage to erection of structures to forestall such occurrences and to achieve a sustainable environment. Besides, property vis-à-vis facility rehabilitation strategy should be adopted on degraded landed properties rather than arbitrary removal and rambling replacements. This should involve improving the existing infrastructural facilities as well as providing new ones with a view of making their services functionally accessible and adequate. To reduce the level of encroachment into natural vegetation in the course of expansion, it is also suggested that vertical expansion should be encouraged in the form of story buildings, high scrappers, and the like. Also, the concept of Smart Growth and Compact City via Urban Growth Boundaries policy that has been implemented in most European and American cities can as well be adopted in the study area. It is believed that this will reduce the rate of land consumption and indiscriminate uses and improve the aesthetic value of the environment.
The existing Master plan of Akure was produced in 1980 and has become inactive, old, and superseded. Thus, there is a need for its review and provision for a more comprehensive regional plan to guide the development and spatial growth of the entire region. These plans are to be administered by a constituted board which is to be saddled with responsibility to maintain an orderly and aesthetic environment in the region. The board is to be made responsible for the preparation and implementation of planning schemes as well as local, area, and structural plans in conformity with the state and national plans. This will go a long way to assist in regulating land use for sustainable development in the area.
The authors declare that there is no conflict of interests regarding the publication of this paper.
This paper is written from the Ph.D. research thesis of J. O. Owoeye titled “Urban Sprawl and Changing Land Use Pattern in Akure Region, Nigeria.” Consequently, the effort of Dr. O. F. Akinluyi and Mr. Femi Adeyeri (School of Earth and Mineral Science, Federal University of Technology, Akure) as well as Dr. Stephen Hall (Centre for Research in Sustainable Planning and Environment, University of the West of England, UK) is quite appreciated for their valuable comments and professional advice on the GIS aspect of the research.