Spatio‐temporal assessment of urban growth of medium‐size and nodal towns for sustainable management: using GIS

Abstract

Purpose -Urban growth has increasingly drawn much attention of erudite scholars due to its central role in achieving a sustainable urbanization. Despite this awareness, studies on urban growth have continued to dwell on the traditional method of presenting geographical Information, which has proved to be slow and inadequate. The purpose of this paper is to adopt a Geographical Information System (GIS) in assessing the spatial pattern and the physical planning problems associated with the expansion of Ore township between 1964 and 2002. Moreover, the study tends to serve as baseline study for subsequent studies on medium-sized and nodal towns. Design/methodology/approach -The study utilized data from secondary sources such as Landsat-TM, February, 1986, Landsat ETM þ , December, 2002; Topographical map of Ore 1964 and population census data of Ore 1991. The study employed ILWIS Academic 3.2 GISsoftware to process the imageries. Coordinates extracted from the topographical map in UTM were used to georeference the enhanced and filtered images upon which supervised classification was performed, followed by error matrix operation and ground truthing to ensure high level accuracy. This results in six domains, namely, built-up, forest reserve, farmland, secondary forest roads and water bodies, which were analyzed on temporal basis. Predictive model was used. Findings -The study found that Ore township occupied an area of 1.2 km 2 in 1964, expanded to 11.3 km 2 in 1986 and 13.2 km 2 in 2002 respectively. The prediction showed a possible expansion of 55.33 km 2 by 2027. The results further revealed physical planning problems generated by these expansions -housing, inadequate waste disposal system, encroachment into agricultural lands, inadequate health facilities and poor drainage system. From field survey, 62 percent of 125 residential housing units sampled disposed refuse themselves, while 20 percent have no organized refuse collection and 18 percent dispose through other means. This suggests the vulnerability of inhabitants to health risks and environment problems. Practical implications -Urban growth data are useful in evaluating environmental impacts, delineating growth boundaries, developing land use zoning plans and estimating the expansion rate of a town to advise the government towards proper planning and distribution of utilities. These can be achieved through the adoption of GIS approaches to information gathering and analysis for regular monitoring and evaluation of development plans. Although it is capital intensive, it is worthwhile. Originality/value -The use of GIS and remotely-sensed data integrated with population census data and topographical map data has demonstrated the capability inherent in the new tools, GIS and remote sensing, to generate to some extent base line data for the town planners, in order to proactively channel the urban development in an appropriate direction, particularly the medium-sized and nodal towns that are somewhat neglected.

Land use/cover change and urban sustainability in a medium-sized city

“…Hitherto, an agrarian town with the predominance of the native population, Osogbo has grown over time to become a regional commercial and industrial centre. The rapid spatial expansion of the city is attributable to population growth, industrial development and political influence (Agbola, 1992;Aguda et al, 2012). The city owes its industrial development to favourable government policy which designated it as one of the regional Industrial Development Centres in 1970(Agbola, 1992 and the impact of the railway line which facilitated the movement of bulky goods.…”

“…Over time, remotely sensed data and geospatial methods of analysis have proven efficient in analysing the earth-system function, patterning, and change at local, regional and global scales (Rajeshwari, 2006). It has particularly been found useful in evaluating environmental impacts, delineating growth boundaries, developing land use zoning plans and estimating the expansion rate of a city growth (Aguda et al, 2012).…”

Population dynamics and infrastructure: meeting the millennium development goals in Ondo State, Nigeria

“…The capital city Akure and other large towns have also witnessed rapid population and structural growth, with the attendant negative environmental impacts in the recent years Aguda et al, 2013).…”