Urban Expansion and Loss of Agricultural Land in Osogbo, Osun State Nigeria, using Multi-Temporal Imageries

Abstract

Osogbo, the state capital of Osun State is one of the rapidly urbanizing cities in Nigeria. This article examined urban expansion and the transition of agricultural land in Osogbo with the use of multi-temporal imageries between 1986 and 2018. Large amounts of cultivated land has been transformed into other land uses in the past 31 years. This paper presents the process of the loss of agricultural land and urban growth in Osogbo with the use of remote sensing and GIS. Landsat imageries for 1986, 2002 and 2018 were used to analyse land use and land cover change. Supervised image classification was applied to classify the images into different land use categories. Six land use classes were identified: built-up area, water body, cultivated area, gallery zone, dense vegetation and rocky outcrops. Built-up areas (residential, educational and industrial areas) have greatly increased while agricultural lands (i.e. farmland and wetland) have considerably decreased during the study period. Built-up area covered 7.06% in 1986 but increased to 53.61% in 2018 while agricultural land decreased from 86.28% to 41.53% in the same period. The study therefore recommends that government should integrate agricultural lands into urban land use, planning for efficient management and protection of the dwindling agricultural space.

Keywords

• urban expansion
• geographical information system (gis)
• loss of agricultural land
• land-use
• land cover