ABSTRACT
A major advance in the field of urban ecology was the conceptualization of cities as an ecosystem. An ecosystem is all the biotic and abiotic components of a system, and ecosystem ecology studies the flows and processes among these different components. Cities are best studied as a patchwork of several different ecosystem types, including wetlands, parks, residential yards, and patches of remnant vegetation. Plants perform ecosystem functions, with the functions that directly benefit humans being termed services. Ecosystem services are classified into: supporting, provisioning, regulating, and cultural. The urban environment is inherently a heterogeneous mix of environmental conditions due to land-use conversion creating a mosaic of land cover and anthropogenic activities generating variable energy use and resource demand. Urban ecosystems are a continuum of management, from highly managed landscapes, such as residential lawns, to relatively unmanaged remnant or rejuvenated ecosystems, such as urban woodlands.
