Urban Land Use Land Cover Changes and Their Effect on Urban Thermal Pattern: Case Study of Nigeria’s Federal Capital City

Abstract

Since the official movement of the seat of government from Lagos to Abuja in 1991, the Federal Capital City being the most habitable area in the entire Federal Capital Territory has continued to experience rising urban population growth; this has resulted in a significant modification of its natural landscape. Such modifications often affect the microclimate of cities. This study investigates the effect of changing urban land use/cover on urban thermal pattern through the application of remote sensing, geographic information systems (GIS) and statistical methods. Land use land cover (LULC) and land surface temperature (LST) were extracted from Landsat 4 TM (1987) and Landsat 8 OLI/TIRS (2014). The result of LULC show that while built-up area and wasteland classes increased by 19.93% (from 23.57% in 1987 to 43.50% in 2014) and 15.87% (from 14.88% in 1987 to 30.75% in 2014) respectively, vegetation cover decreased by 35.63% (from 60.63% in 1987 to 25% in 2014). This significant vegetation cover loss to both built-up area and wasteland is an indication of man’s dominance of the landscape of the city.  The study revealed that the lowest values for minimum, maximum and mean temperature occurred in 1987 (17.03, 31.16 and 24.3°C respectively) while the highest values for minimum, maximum and mean temperature occurred in 2014 (25.01, 37.38 and 32.54°C respectively). In 1987, relatively lower LST values (23-26°C) were dominant occupying about 84.38% of the total land area while, in 2014; higher LST values (31-34°C) were dominant occupying approximately 84.14% of the total land area. These results show that a significant portion of the natural landscape elements of the FCC has been removed due to rapid urbanization and this has resulted in the formation of hotspots across the city. The results of this research bring to fore the need for urban planners in the FCC to put in place temperature-mitigation strategies so as to ensure the sustainability of the city.

Keywords: LULC; LST; classification; FCC; SUHIs