Vehicle Exhaust Emission Characteristics and Contributions in the Pearl River Delta Region

A vehicle emission inventory was developed for the Pearl River Delta(PRD) region in 2006.The inventory was used to analyze the contributions from different vehicle types,different cities,and fuel usage to the total vehicular emission in the PRD.The results show:(1) There are significant differences in the emission contributions among different vehicle types.Heavy-duty gasoline trucks,light-duty gasoline passenger cars,and light-duty gasoline trucks were the major NO_x emission contributors.Motorcycles,light-duty gasoline trucks,and light-duty gasoline passenger cars contributed most to the VOCs emissions.Heavy-duty diesel trucks,heavy duty diesel passenger cars,and light-duty diesel trucks were the main contribution sources of PM_10.(2) The developed and rapidly developing cities such as Guangzhou,Fushan,Dongguan and Shenzhen are major contributors to total motor vehicle emissions in the PRD region;the emissions from these cities account for 79.7%,69.8% and 77.9% of the total vehicular NO_x,VOCs,and PM_10 emissions,respectively.(3) The ratio of diesel vs.gasoline showed significant effects on pollutant emissions.Gasoline vehicles make significant contribution-about 93.8%-to total VOCs emissions,while diesel vehicles contribute about 61.5% and 84.0% to the total NO_x and PM_10 emissions,respectively.