Urban development impact on climate variability and surface water quality in part of Mangaung metropolis of South Africa

Abstract

ABSTRACT The overpopulation of urban centres accelerates land use patterns, slum creation and generation of contaminants. As such, this study seeks to investigate the impact of rapid urbanisation on climate variability and surface water quality around Mangaung metropolis. Remote sensing was employed to analyse land use land cover (LULC), normalized differential vegetation index (NDVI) and normalized differential water index (NDWI) changes for a period of 30 years in the Mangaung metropolis. Furthermore, the historical water quality of important rivers and dams were studied in respect of urban contamination. LULC revealed that the urban areas increased exponentially which led to increased loss of vegetation cover and shortage of water availability. The rainfall and water type evolution suggests the influence of urbanisation. This suggests urbanisation accelerates the loss of vegetation cover, thus causing an increase in temperature and reduction in the amount of rainfall, thereby reducing the surface water quantity in the study area.