Edge-Urbanization: Land Policy, Development Zones, and Urban Expansion in Tianjin

Fast-paced urban growth in China has produced a specific, transient form of urban periphery, which continuously shifts outwards as the city expands. Seeing this process as a distinctive type of (sub)urbanization, this paper encapsulates it under the notion of edge-urbanization. The paper argues that edge-urbanization in China is fueled by deliberate government policies, which seek to mobilize peripheral land for high-growth strategies. The relationships between urban expansions and spatial economic policy are analyzed more closely in the case of Tianjin. Geospatial analysis derived from satellite imagery for the period of 1980-2015 reveals the morphological and temporal dynamics of urban growth in the post-reform era. Built-up land in Tianjin has expanded 1.8 times during this period, with the dominant growth type being edge-expansion. This character of urban expansion is shown to be closely associated with government's project fever setting up development zones and new economic activity on city edge. The results demonstrate a decisive role of the state in shaping (edge) urbanization in China's major cities.