Multiscenario Simulation and Prediction of Land Use in the Urban Agglomeration in the Middle Reaches of the Yangtze River Considering Urban Expansion and Shrinkage

Urban expansion and shrinkage are two sides of the same coin in the process of urbanization, jointly influencing the evolution of land use. However, the specific impacts of urban expansion and shrinkage on land-use evolution have not yet been thoroughly explored. This paper selects the urban agglomeration in the middle reaches of the Yangtze River as the research area and constructs an evaluation index system to understand the multidimensional expansion and shrinkage of cities. On this basis, the system dynamics model and cellular automata model are combined to predict the multiscenario evolution of land use. The results indicate that from 2010 to 2020, the proportion of shrinking cities in terms of population and economy was 51.61%, while the proportion in terms of social environment was 45.16%. Compared with the natural development scenario, the rapid expansion of construction land in the economic growth scenario from 2020 to 2050 will lead to a decrease in land-use efficiency. The social development scenario focuses more on improving social public services, and the expansion of construction land is second only to the economic growth scenario. In environmental protection scenario, the transition between land-use types is the smoothest, which is beneficial for environmental protection. The evolution of future land use should gradually shift toward an environmental protection scenario, thereby promoting the sustainable use of land resources. This study provides a deep understanding of the impact of different levels of urban expansion and shrinkage on land-use evolution, which can help provide a reference for the formulation of land space planning and coordinated development.