Explore the dynamics of land- use changes and its impacts on land surface temperature in greater Kampala metropolitan area.

Abstract

Over the years, human activities have continuously decreased the vegetation cover of the earth’s surface especially the terrestrial ecosystems at the global scale. These changes in the natural environment have directly and indirectly affected the land-use change conditions within the GKMA leading to the extensive decline in the areal extent of vegetation and wetland areas while the proportion of impervious surfaces are ever growing. The objective of this study therefore is to determine the relationship between land-use change and the Land Surface Temperature in the GKMA. The first objective determined the land-use change of the GKMA from 2001 to 2016 using supervised image classification. The results indicated that the land-uses in the GKMA have been progressively converted into built-up areas such as concrete buildings, paved roads and paved surfaces. The built up areas significantly changed the urban landscape by occupying 19.8% of the total areal extent in 2001, 33.38% and finally 37.66% in 2016. The second objective which quantified the LST of the GKMA showed that the temperatures ranged from 12.48°c to 22.27°c in 2001, 12.35°c to 35.25°c in 2010 and 15.51°c to 28.21°c in 2016. The third objective quantified the relationship between the land-use change and the LST of the GKMA. This objective adopted a zonal statistics tool and correlation analysis in assessing the relationship between land-use changes and LST. The results showed that water and wetland areas had the least LST while vegetation and built-up areas had the highest LST. Furthermore, correlation analysis tool showed a strong relationship between LST and the land-use indices. LST and NDVI showed an inversely proportional relationship that is an increase in the LST recorded a decrease in the NDVI. LST and NDBI showed a directly proportional relationship where by an increase in the LST depicted an increase in the NDBI. This study vividly demonstrated the potential of multi-temporal Landsat images in monitoring land-use change and LST dynamics in the GKMA. Exploring the relationship between land-use change and LST can be useful for urban planners and decision and decision makers for sustainable urban planning and to discover ways to solve the urban problems.