The book examines the influence of road transportation development on pollution concentration and distribution by providing background information on urbanization and ambient air pollution. it examines problems and limitations of monitoring pollution concntration along traffic corridors by setting up of monitoring stations for direct and indirect measurement of microclimatic variable, elemental and gasseous pollutants,comparissons were made between dirrect measurement of air pollutantants and indirect bio-monitoring with Terminalia catappa L leaves and examines the inter-relationship between traffic density, land use and microclimatic changes