Landscape metrics analysis of land use patterns and changes in suburban local government areas of Ibadan, Nigeria

Abstract

This study examined the spatiotemporal pattern of urban growth and magnitude of changes in selected Local Government Areas (LGAs) in the suburban area of Ibadan using remote sensing cum spatial metrics. Data for the study were obtained from administrative maps of the study area, population data and satellite imageries. All of these were complemented with ground validations using Global Positioning System (GPS) receiver. Periods of change analysis were divided into two epochs; 1986 to 2002 and 2002 to 2017. The imageries were classified into four landuse/cover classes based on Anderson’s modified version of supervised classification scheme. Accuracy assessment of the imageries was carried out using 100 randomly sampled ground truth points. Ten spatial metrics were selected for analysis using Fragstats program. Results show a significant loss in vegetation due to conversion (Land Consumption Rate, LCR = 0.025, 0.019 and 0.027; Land Absorption Coefficient, LAC = 0.012 and 0.048). Moreover, there was a persistent increase in Number of Patches (NP) indicating a scattered and fragmented but continuous development. However, dwindling values of Patch Density (PD = 90.94, 27.07 and 30.30) indicate expansion through conversion of other landuses at varying rates. Results also indicate an incidence of fragmented low density development in the fringe areas (Area Weighted Mean Patch Fractal Dimension, AWMPFD = 1.37 and 1.39). The study highlights the chaotic land development and unrestrained urban expansion in the study area.

Evaluation of Land Cover Dynamics and Landscape Fragmentation in Ijebu Ode, Nigeria

“…Results of the growth and pattern of land use development in Ijebu Ode between 1986 and 2021 indicated that there has been continuous increase in the growth of the built-up area which was a by-product of reduction in vegetation and cultivated land classes. By implication, this denotes the prevalence of urban expansion in the area as earlier reported in some earlier studies which noted the existence of inverse relationship between the built-up and other LULC such as vegetation [31,32,49,53].…”

“…Urban landscape fragmentation is usually the consequence of changes in landscape structure [18,19,27]. These changes are by-products of decreasing heterogeneity of landscape compositions and profound landscape fragmentation [28][29][30][31][32][33][34].…”