Spatiotemporal Dynamics and Drivers of Human Activity Intensity in Major Urban Agglomerations of China from 1990 to 2020

Urban agglomerations have become the primary form of urbanization in China and serve as a principal means of promoting the nation’s high-quality economic development. As a key driving force behind the development of urban agglomerations, human activity intensity plays a critical role in understanding and regulating their sustainable development. In this study, we estimated the human activity intensity of land surface (HAILS) for five major urban agglomerations in China from 1990 to 2020 based on the land cover. Trend analysis and spatial autocorrelation analysis were employed to examine the temporal dynamics and spatial aggregation pattern of HAILS. Furthermore, effectiveness of the HAILS index was validated and the driving factors of HAILS changes was explored. The results indicated that areas with higher HAILS were mainly concentrated in the plains, while high-altitude regions exhibited lower HAILS values. From 1990 to 2010, human activity intensity increased significantly across all five urban agglomerations, followed by divergent trends after 2010. HAILS showed a strong correlation with population density in artificial surfaces, but weak correlation in the natural and artificial vegetation cover. Changes in human activity intensity were found to be largely influenced by national and local policies. These findings underscore the value of quantifying human activity intensity in urban agglomerations, offering insights into their spatiotemporal dynamics and development patterns, as well as providing theoretical and practical support for policy formulation.