Spatial Distribution of Urban Heat Islands and Vegetation Cover Loss in Kaduna City, North West Nigeria

Urban expansion in Nigerian cities is associated with the replacement of natural vegetation with impervious surfaces, contributing to elevated land surface temperatures and the formation of urban heat islands. This study examined the spatial distribution of urban heat islands and their relationship with vegetation cover changes in Kaduna City over a ten-year period. Landsat 8 satellite imagery was used to derive land surface temperature maps and Normalised Difference Vegetation Index values for 2013 and 2023. Land use and land cover maps were produced through supervised classification and change detection analysis. Results revealed a significant increase in built-up area from 34 percent to 61 percent of the study extent, with corresponding reductions in green space and bare soil patches. Land surface temperature in built-up zones exceeded those of vegetated areas by up to 8 degrees Celsius, with the most pronounced heat island effect concentrated in the central business district and industrial areas. A strong negative correlation was found between Normalised Difference Vegetation Index values and land surface temperature across all land cover types. The study recommends incorporation of green infrastructure, including urban parks and tree-lined corridors, into the Kaduna State urban master plan, alongside incentives for green rooftop installations in commercial buildings. Keywords: urban heat island, vegetation cover, land surface temperature, Kaduna, remote sensing.