ABSTRACT
Urban areas respond to, and are responsible for, changes in biochemical and climate cycles (Grimm et al. 2008). Many urban areas in the world have been undergoing persistent expansions in urban land use, transportation system, and automobile usage. Urban centers that provide habitats for human beings are also point sources of CO2 and other greenhouse gases, as well as trace gases such as NO, NO2, O3, and other organic acids.
