Assessment of land use/land cover changes and their impacts on land surface temperature in Bangui (the capital of Central African Republic)

Abstract

Extreme land-use and land-cover (LULC) as the result of rapid urbanization has been raising land surface temperature of core city areas and its surrounding. Therefore, investigation on surface temperature is very vital to analyze temperature variations and minimize its effect. This research aims to analyze the impacts of LULC changes on LST in Bangui city, Central African Republic using combined techniques of remote sensing and GIS. The result of this study indicates that there was a significant change in LULC between 1986 and 2017 particularly expanded in vegetation and built-up areas and declined in bare soil. For instance, built-up increased by + 130.29 % with a rate of 137.06; and vegetation increased by 8.44% or a rate of 17.2. Whereas bare soil was sharply declined by −35.33% for a rate of −155.83. The mean LST of the city firstly decreased from 26.24 °C in 1986 to 23.37 °C in 1999 and increased to 27.23 °C in 2017. The study also stated that the mean LST of built-up areas increased from 26.21 °C in 1986 to 27.59 °C in 2017. Besides, the mean LST of bare soil raised from 26.51 °C to 27.33 °C in 1986 and 2017 respectively. These indicate that built up and bare soil experienced high LST than vegetation and water body. The study found a positive correlation between NDBI and LST whereas negative correlations of LST with NDVI and NDLI. City planners should be implemented urban green belts and green roof to mitigate the effect of surface urban heat islands (SUHI) in the city and its surooundings.

Keywords

• Remote sensing
• NDBI
• NDVI
• NDLI
• LST