Regional Economic Integration Around a Large Urban Agglomeration: A Case Study of Regions Around the Pearl River Delta from the Perspective of Nighttime Light

The process of regional economic integration and convergence among different regions in Guangdong Province has been implemented for three decades. Whether the difference in regional economy is reduced in Guangdong is a concern. This research adopts the beta-convergence analysis for the border effect to investigate this issue. The analyses are based on NPP-VIIRS nighttime light data in East, West, and North Guangdong and the Pearl River Delta. The results showed that border effects between cities inside East Guangdong and West Guangdong, between West Guangdong and the PRD, and between North Guangdong and the PRD are enlarging. Decreasing regional differences only occur in some city borders inside North Guangdong and between East Guangdong and the PRD. However, for town-level units along city borders, diminishing border effects are found between cities in and around the PRD in these units. Industrial synergy provides partial explanations for the observed trends of economic convergence. These trends hold crucial theoretical and practical significance for discussing strategies to reduce income disparities among different cities and achieve the coordinated development of multiple economic centres within urban agglomerations.