Nighttime light metrics for analysing urban-rural economic disparities: A case study in 36 Chinese metropolitan areas

Abstract

Rapid urbanization in China has driven significant economic growth, but the urban-rural economic disparity (URED) continues to widen. This growing disparity impacts domestic productivity, consumer demand, rural stability, and the achievement of common prosperity. To address this issue and promote sustainable development, understanding the spatiotemporal patterns and drivers of URED is essential. This study employs nighttime lighting (NTL) data to analyse URED changes in 36 Chinese metropolitans at three scales. The study results show that: (1) From 2000 and 2022, both the economic volume and area of the study regions grew more than fivefold, but the economic gap between urban and rural areas significantly widened. (2) Economic growth in Predominantly Urban regions has escaped area constraints, while other regions still rely on spatial expansion. (3) URED has shown a steady increase, with higher values in the southeast and lower values in the northwest. (4) Differences in policy implementation and geographic location strongly influence URED. The study confirms the effectiveness of NTL data in capturing urban-rural economic dynamics and the reliability of spatial entropy in measuring URED. Future research will further explore NTL data patterns and integrate additional urban attributes to provide deeper insights into URED.