Quantifying the CO2 Emissions of Motor Vehicles and the Urban Tree Carbon Sequestration Potential in the Lusaka Central Business District, Zambia

This research was conducted in the Central Business District (CBD) of Lusaka, the total area of the CBD is 2.7 km2. The aim of this study was to quantify the CO2 emissions of motor vehicles contributing to the negative impacts of climate change and urban tree CO2 sequestration potential in the Lusaka CBD. Specific objectives of this study were to: Assess the amount of carbon emitted by the daily motor vehicle fleet in the CBD of Lusaka; assess the amount of green spaces required to offset the current motor vehicle CO2 related emissions in the CBD of Lusaka. The research design for this study was a field survey. The daily urban fleet in the CBD of Lusaka was physically counted from the four main entry points during pick hours. On the other hand, the research took into consideration the fact that the CBD has a few trees in selected places, therefore all trees with a diameter greater than 5cm were considered for carbon capture. The data for both categories was subjected to mathematical models to estimate the CO2 emissions as well as amount sequestered. The data collected indicate that there were 17 plant species and 424 individual trees in the CBD of Lusaka. Among tree species, Trichilia emetic had the highest number of plants up to 174 followed by Delonix regia having 70 plants. The most dominant species of plant in the central business district of Lusaka are Trichilia emetic and Delonix regia as a result of planting activities promoted by the government in the previous years. Despite the earlier mentioned species having high numbers of individual plants, Afzelia quanzensis recorded the highest carbon sequestration of up to 2.868 tons. Total Carbon sequestered by plants in the CBD of Lusaka is 15.729 tons. The projected amount of carbon that will be sequestered the following year is 17.353 tons. This indicated that the amount sequestered by plants every year is 1.757 tons. The results obtained from Lusaka CBD also indicated that the daily motor vehicle fleet consumed approximately 3174.212 litres of fuel which release about 19.656 tons of CO2