Comprehensive greenspace planning based on landscape ecology principles in compact Nanjing city, China

Urban greenspaces are universally valued as amenity-recreation venues, wildlife refuges and essential livable-city ingredients. Western strategies of urban greenspace provision are difficult to implement or retrofit in most Asian cities, commonly constrained by a high-density compact form. With recent rapid urbanization and associated brown and green field developments. ample opportunities arise to overhaul greenspace standards and patterns. The case study of the ancient city of Nanjing in China pen-nits planning for an integrated greenspace network, aiming at flexibility for future urban expansion, green field acquisition, recreational functions, wildlife habitats and environmental benefits. It consists of green wedges, greenways and green extensions that incorporate urban green areas at three landscape scales. At the metropolis scale, through normative and substantive analyses of urban form and urban expansion, and assessment of suburban uplands, five green wedges are demarcated to generate a star urban form. The green wedges link the extensive countryside to the central city, and define elongated finger-like spaces between them for urban expansion to avoid conflicts with green fields. At the city scale, three major greenways, including city-wall circular greenway, Inner-Qinhuai River greenway, and canopy-road greenway, are designed as a permeating framework to guide new greenspace location, configuration and continuity, and to link existing parks. These greenways are equipped with a comprehensive trail system to foster pedestrian and cycling movements that are preferred by the public and the government. At the neighborhood scale, a greenspace organization, consisting of residential public open spaces, shaded sidewalks and riparian strips, conforms to the network geometry. As well-connected entities, these small proximate enclaves provide opportunities for residents to have day-to-day contact with nature. They also serve to resist undue urban influences and intrusions. Overall, the three-tiered greenspace system provides an alternative mode for urban development to the conventional transport-dominated one, to usher substantial improvement in landscape-environmental quality and to augment the sustainable-city notion. (C) 2003 Elsevier Science B.V. All rights reserved.