Spatiotemporal Patterns and Driving Forces of Urban Expansion in Coastal Areas: A Study on Urban Agglomeration in the Pearl River Delta, China

Abstract

Since the beginning of the 21st century, the spatial pattern of urban expansion and the mechanism of urbanization in coastal areas have undergone significant changes. This study aims to reveal the spatiotemporal patterns of urban land expansion and analyze the dynamic driving forces of urban agglomeration in the Pearl River Delta of China from 2000 to 2015. The urban-land-expansion intensity index, expansion difference index, and fractal dimension were used to study how the urban land in this area was developed, and the geographical detector was applied to explore the relative importance, expansion intensity, and interactions of physical and socioeconomic factors. The results revealed that the urban-land-expansion intensity of the Pearl-River-Delta urban agglomerations exhibit a downward trend, while cities exhibited a trend of developing more coordinately from 2000 to 2015. Physical factors determined the direction and scale of urban development, and the urban land expansion in the Pearl-River-Delta urban agglomeration is mainly distributed in plain areas that have an elevation below 120 m and a slope less than 5°. Socioeconomic factors have a greater influence on the expansion of urban land, and their effects have changed over time. Population growth and economic development has played a significant role in the expansion of urban land before 2005. Subsequently, the factor of GDP and distance to the core cities of Guangzhou and Shenzhen controlled the expansion to the greatest extent. The impacts of various factors tended to become balanced during 2010–2015. The majority of the factors enhanced each other via their interactions, and the distance to the rivers always exhibited a greater enhancement when there was interaction with other factors. The spatial and temporal analysis of the urban expansion and the mechanism of the Pearl River Delta urban agglomeration could provide useful information for coastal urban planning. This study also offers new knowledge regarding the interactions between different drivers of urban land expansion.

Spatiotemporal Characterization of the Urban Expansion Patterns in the Yangtze River Delta Region

“…Having examined the Beijing-Tianjin-Hebei urban agglomeration, this study found that the expansion rate of Beijing during 1995-2000 was 2% [67], whereas the expansion rates of eight cities in the YRDR had been higher: CU (2.6%), JH (4.9%), LS (3.1%), MAS (3.7%), NJ (2.8%), WZ (3.8%), and WH (2.2%). The highest expansion rate in the Pearl River Delta urban group was GZ (14.1%) during 2000-2005 [19]. The expansion rate of SZ was 2.6% during 2005-2010 [19].…”

“…Research on urban spatial clusters began as early as the 1920s, using megalopolis [18], urban agglomeration [19,20], city group, and city cluster to describe such urban spatial organization [21]. Urban agglomerations were initially defined as a central city and several surrounding towns [22].…”

Investigation of Dynamic Coupling Coordination between Urbanization and the Eco-Environment—A Case Study in the Pearl River Delta Area

“…In previous studies, the Pearl River Delta is a region which gained much attention. As a rapidly urbanizing area, the Pearl River Delta faces a contradiction between urbanization and the eco-environment, which is manifested by the decline in the quantity and quality of natural resources, the increase in urban environmental pollution, and the deterioration of the natural eco-environment, which has severely restricted the sustainable development of the region [15][16][17][18].Thus, some studies have addressed the spatial differentiation characteristics of the coordination between urbanization and the eco-environment in the Pearl River Delta [8,13]. However, coordination is generally calculated based on the status quo data, and not on incremental data.…”

Spatial Evolution of Urban Expansion in the Beijing–Tianjin–Hebei Coordinated Development Region

“…The comprehensive index was used to classify the types of urban expansion in prefecture-level cities, and the spatial distribution difference of urban expansion types in each city was analyzed. (3) Although many scholars have used linear regression [41], ridge regression [42], a geographic detector [43], a spatial econometric model [44], and other methods to quantitatively study the influence of multiple factors on urban land, the existing research pays little attention to the temporal coevolution of urban land area with urban population and GDP. Using the power scaling law, Fei and Zhao [45] calculated the scaling coefficient of urban population and urban land area, as well as that of urban GDP and urban land area.…”