IMPACT OF URBANIZATION ON SOIL QUALITY AND HEAVY METAL CONCENTRATIONS IN SELECTED AREAS OF ILORIN WEST LOCAL GOVERNMENT AREA

Abstract

Soil quality is strongly influenced by land-use practices, which modify nutrient status, organic matter dynamics, and 
contamination levels. While urbanization, modernization, and population growth drive economic development, they 
also adversely affect soil systems through pollutant accumulation and physicochemical alteration. This study 
assessed the spatial variability of soil quality indicators such as pH, electrical conductivity (EC), organic matter, 
moisture content, available phosphorus, total nitrogen, and selected heavy metals (Pb, Cd, Cr, Cu, and Ni) across 
traffic-congested, residential, industrial, and undisturbed land-use types in Ilorin West Local Government Area, 
Kwara State, Nigeria. Results indicated relatively stable pH values (6.2–6.5) across sites, while electrical 
conductivity was markedly elevated in residential (53.33 dS m⁻¹) and industrial soils (20.00 dS m⁻¹), suggesting 
substantial anthropogenic ionic inputs. Organic matter content was highest in undisturbed soils (1.44%) and lowest 
in industrial soils (0.14%). Industrial soils recorded the highest concentrations of Pb, Cr, and Cu, whereas elevated 
Cd and Ni concentrations occurred in undisturbed soils, suggesting possible geogenic or legacy influences. Principal 
component analysis identified two dominant components explaining 78.1% of the total variance, distinguishing 
between fertility-related factors and heavy-metal contamination. These findings demonstrate the strong influence of 
urban land use on soil quality and highlight the need for routine monitoring and land-use-specific management 
strategies in rapidly urbanizing environments.