ABSTRACT
Rapid urbanization is threating the security of resources due to increasing demand. The influx of people into urban areas is causing changes to urban landscapes, as well as resulting in high unemployment and crime rates, pollution and urban sprawl. In addition, urban landscapes are encroaching and disturbing ecological infrastructure. Changes in the built-up area in Harare, Zimbabwe, between 1986 and 2018, were quantified using multispectral remote sensing. Land-use classification was done using Landsat images (urban and non-urban areas) using the random forest machine learning classifier. The developed land-use images were overlaid on population maps to compare urban growth with population increase. The influence of urban growth on climate change was assessed through an analysis of the changes in land surface temperature (LST), which was derived from a transect of different Landsat images over the review period. There are notable spatio-temporal, demographic and environmental transformations evidenced by the increasing urban population, land-use changes and rising temperatures. The built environment increased by more than 185 per cent between 1986 and 2018, at a rate of more than 5 per cent per annum. There were positive trends in landscape metrics, with the number of patches decreasing from 20,877 to 9,865. Significant increase in LST occurred due to the increase of impervious surfaces.
