The 'ADaM cube': Categorizing Portland, Oregon's Urbanization Using GIS and Spatial Statistics.

摘要

Transportation availability and land use intensity demonstrate a strong relationship, with intense development concentrated near significant transportation investment. Transportation networks evolved in response to emergent transportation technologies and changing urban land uses. The irregular distribution of transportation systems reinforced patterns of land use development, shaping urban form. Understanding the relationships between transportation and the intensity of land uses allows urban geographers and city planners to explain the urbanization processes, as well as to identify areas historically susceptible to future development. The goal of this research is to develop a quantitative framework for the analysis of the development of urban form and its relationship to urban transportation systems.;This research focuses on transportation accessibility, building density, and the structural massing as the basic metrics in the categorization of urban form. Portland, Oregon serves as the case study environment, while the research methodology examines the spatial and statistical relationship between these metrics for much of the city's urban area. Applying geographic information systems (GIS) and k-means cluster analysis, urban form metrics are compared within the ADaM (Accessibility, Density, and Massing) cube, a model demonstrating comparative relationships, as well as the geographic distribution and patterns of urban form in Portland, Oregon's neighborhoods.;A finalized urban form catalog describes existing urban environments, but also indicates areas of impending transition, places having the strong potential for reorganization with respect to higher levels of transportation accessibility. The ADaM Cube is a tool for characterizing Portland's existing urban form, and describing the vulnerabilities of urban neighborhoods to the pressure of redevelopment.