The impact of the construction of national economic and technological development zones on urban form:A case study of the Yangtze River Delta Region
The establishment of national economic and technological development zones was a pioneering initiative in China's economic system reform,which has had a profound impact on promoting regional economic development and urban spatial restructuring.Based on land use data from the Yangtze River Delta Region over the past 30 years,the evolutionary characteristics of urban form,including its external contours and internal patterns,are comprehensively depicted from five dimensions:scale,form,compactness,fragmentation,and diversity,using landscape metrics.Methods such as buffer analysis and multi-period difference-in-differences model are employed to examine the effects and mechanisms of national economic and technological development zones on urban form evolution at multiple scales.The results indicate that:(1)Both the 3 km and 5 km buffer zones have undergone a transition from rural to urban areas,and the urban form has become more regular and compact,with some spatial differentiation characteristics.(2)The construction of national economic and technological development zones has led to a decrease in shape metrics and an increase in compactness metrics within the two buffer scales,as well as a significant reduction in the size metrics within the 5 km buffer zone.(3)Factors such as the agglomeration and restraint effects of national economic and technological development zones on various production factors,the jurisdiction mode of administrative trusteeship,and excessive land use by enterprises have jointly shaped the evolution pattern of urban form in surrounding areas.The"top-down"development model of national economic and technological development zones not only attracts numerous production factors but also formulates and implements various supporting policies and plans.This plays a crucial role in driving urban expansion,establishing development boundaries,and regulating land use order.It is the direct cause for inducing the regularization and compactness of urban form.
urban formland usedifference-in-differences modelnational economic and technological development zoneYangtze River Delta Region