Analysis of Urban Expansion and Land Use/ Land Cover Changes in Abeokuta, Nigeria using Remote Sensing and Geographic Information System Techniques

H. Oluwasegun Adebayo; O. Olukayode Oyesiku; B. Bamidele Badejo

doi:10.58709/niujhu.v9i2.1910

H. Oluwasegun Adebayo Olabisi Onabanjo University, Ago Iwoye, Ogun State, Nigeria
O. Olukayode Oyesiku Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria
B. Bamidele Badejo Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria

DOI: https://doi.org/10.58709/niujhu.v9i2.1910

Abstract

Since 1976, Abeokuta has functioned as the administrative centre of Ogun State, Nigeria. During this time, significant changes have occurred in its physical landscape, urban growth, and sprawl. These changes, driven by factors affecting Land Use/ Land Cover Changes (LULCC), pose environmental challenges such as transportation issues, land degradation, and pollution. This research investigates the impact of urban expansion in Abeokuta using Remote Sensing (RS) and Geographic Information System (GIS) techniques to monitor changes in land use and land cover from 1972 to 2022, and assess their environmental implications. The study identifies various Land Use and Land Cover (LULC) types, employing maximum likelihood classification to categorise features based on spectral signatures. Using imagery from Landsat satellites (TM4-5 for 1972,1984, 1992, TM7 for 2002, 2013, and OLI/MSS for 2022), the features were grouped into four primary classes: built-up areas, vegetation, drainage, and soil lands. Each year's data was processed using ArcGIS 10.5 to calculate the area covered by each land use class. The results illustrate notable changes in Abeokuta's LULC over the years. Specifically, the proportion of built-up areas increased from 0.66% in 1972 to 10.93% in 2022, while vegetation cover decreased from 93.66% to 58.82% during the same period. Drainage fluctuated, reaching a peak of 4.07% in 1992 but reducing to 2.23% by 2022. The soil land also varied, with significant shifts observed over the studied years (3.54% to 28.02%). The expansion of built-up areas at the expense of vegetation can be attributed to the conversion of natural vegetative surfaces into settlements and impermeable surfaces. The study underscores the importance of effective urban planning and enforcement of planning regulations by local and state governments in Abeokuta. This proactive approach is crucial to curbing the unplanned growth of the city and mitigating its adverse environmental impacts.

Keywords: Urban Expansion, Land Use/Land Cover Changes, Remote Sensing, Geographic Information Systems, Abeokuta