Measuring the Urban Sprawl of a Mega-Urban Agglomeration Area Based on Multi-Dimensions with a Mechanical Equilibrium Model: A Case Study of the Yangtze River Delta, China

Abstract

In the context of rapid urbanization, inefficient, disorderly, and low-density urban sprawl often leads to resource waste and ecological damage. Over the decades, many studies on the measurement, analysis, and governance of urban sprawl have emerged. However, existing approaches lack in-depth research on distinguishing effective expansion from inefficient sprawl. Given the limit of land use resources and the demand for urban development, an accurate and reasonable method for urban sprawl measurement is needed. This study proposes an urban sprawl identification method based on a mechanical equilibrium model to analyze the spatial distribution and spatiotemporal evolution characteristics of inefficient sprawl, using the Yangtze River Delta’s (YRD) urban agglomeration as an example. The study found the following: (1) The inefficient sprawl in the YRD was 5219, 1189, and 980 km2 in the three five-year periods between 2005 and 2020. (2) From 2005 to 2020, the inefficient sprawl in the YRD was, on the whole, a weakening trend, but Shanghai and Zhoushan showed an accelerating trend of inefficient sprawl. (3) The proposed method is applicable to most urban development patterns and provides implications for urban sprawl control in mega-urban agglomeration areas, such as the YRD.

Changes in Economic Network Patterns and Influencing Factors in the Urban Agglomeration of Guangdong–Hong Kong–Macao Greater Bay Area: A Comprehensive Study

“…Theoretical research has revealed that the formation and development of urban agglomerations adhere to the principles of spatial crystal structure combination [38]. This implies that polycentric urban agglomerations typically exhibit characteristics such as gradual growth [39], low compactness [40], and weak centrality [41]. Due to the practical requirements of China's Belt and Road Initiative, there has been a growing trend of enhanced and extensive economic cooperation among cities within this area, leading to an accelerated process of regional economic integration.…”