Remote Sensing Insights into Urban–Rural Imbalance and Sustainable Development: A Case Study in Guangdong, China

Urbanization challenges city sustainability by aggravating uneven population migration and land exploitation. Understanding the characteristics and dynamics of this imbalance is crucial for promoting sustainable development. With a focus on population-related land change, this study analyzes the urban–rural imbalance characterized by settlement expansion from 1985 to 2019, using nighttime light (NTL) remote sensing imagery and global settlement distribution data, with Guangdong province, China, as a case study. The key findings reveal significant spatiotemporal differences in settlement expansion between the urban and rural regions. The urban settlements experienced faster expansion from 1985 to 2005, which slowed post-2005, while the rural settlements maintained a stable growth rate throughout the study period. The economic and environmental conditions were identified as major drivers of expansion diversity, with economic factors playing a dominant role in the urban regions and both factors influencing the rural regions. A linear regression analysis highlighted the diverse quantity relationships between the urban and rural settlements across different spatial extents; the urban settlements dominated in quantity at the provincial level, primarily due to the contributions of the core Pearl River Delta (PRD) region. In contrast, the rural settlements outnumbered the urban ones in most of the other prefectures, a trend that continued to deepen across Guangdong province. The findings of this study provide deeper insights into the characteristics and evolvement of the urban–rural imbalance, policy implications and actionable strategies are offered for equitable and sustainable city development.