ABSTRACT
This chapter describes the unique physical, chemical, and biological aspects of ecosystems within urban areas and describes how urbanization can serve as an analog for global climate change. It presents a conceptual model of carbon (C) flow and traces gas fluxes in forest ecosystems and discusses how urbanization and/or global change can affect key pools and processes within this model. The chapter presents data from a comparison of biogeochemical processes in urban and rural forest soils in the New York City Metropolitan Area. The Urban-Rural Gradient Experiment (URGE) study sites are located on a 20 km wide by 140 km long transect that extends from highly urbanized Bronx County, NY, through suburban Westchester County, NY to rural Litchfield County, CT. As expected, New York City produces a marked "heat island" effect. Annual mean temperatures over the period 1985–1991 were more than 3° C warmer in the urban core that at the rural end of the transect.
