How do planning intentions spatiotemporally drive 3-D urban growth?

Abstract

Spatial planning is conducive to guiding urban growth to efficiently achieve urban sustainability. However, assessing the causal effects of planning practices on three-dimensional (3-D) urban growth at the local level is empirically challenging. In this study, Austin, Texas was selected to evaluate the causal effects of plans on the 3-D urban growth, measured by impervious surface fraction, building surface fraction, and building height. The propensity score matching method was applied to construct an artificial control group of land use pixels and subsequently evaluate the effects of the two planning intentions, i.e., planned development centers and planned protected areas, on the 3-D urban growth respectively over two plan periods. Results show that the growth rates of three urban morphology components were significantly lower in the second period. The causal effect analysis provides empirical evidence of the success of spatial planning practice in guiding urban growth to the centers and away from parks and open space during the second plan period. The study proved that detailed 3-D urban dynamic monitoring and propensity score matching ultimately helps to understand how planning intentions affect different aspects of urban growth, which further contributes to a deeper understanding of spatial heterogeneity in complex urbanization processes.