Study on Urban Spatial Growth Simulation Considering Uneven Rates of Stock Renewal and Incremental Development
In China,the majority of cities are currently transitioning from incremental planning to inventory planning. The implementation of inventory planning still relies on incremental planning as its foundation,with the two approaches complementing each other and developing in coordination. During this transition,the new national spatial planning system emphasizes the hierarchical transmission of planning,guiding and constraining urban development progressively from macro to micro levels. This study is based on a multi-level Vector Cellular Automata (VCA) model. We use land use data from Jiangyin City in 2012 as the foundation to simulate and analyze land use changes in 2017,and then verify the accuracy of the VCA model. Subsequently,adhering to the spatiotemporal patterns of stock renewal and incremental development,parameters are adjusted and area allocations are made separately to integrate these two indicators. They are then incorporated into the multi-level VCA model. This approach allows for a multi-level simulation of urban spatial growth,considering both stock renewal and incremental development. Then,this approach is applied to predict and analyze multiple scenarios of land use growth in Jiangyin City in 2027 within the context of stock planning. The conclusions of the study are as follows:① The multi-level VCA decomposes differential driving forces from top to bottom and transmits them collaboratively from bottom to top,achieving both the implementation of upper-level control indicators and fine-grained control of land use simulation. ② The multi-level VCA assigns differentiated speed parameters to different regions,fully considering the spatial heterogeneity of driving factors and land distribution. The overall Figure of Merit (FoM) reaches 24.6%,which is 2.5% higher than that of the single-level VCA. At the local detail level,the multi-level VCA exhibits fewer misclassifications of different land use types and less encroachment on prohibited areas such as water bodies compared to single-level simulations,with better simulation results for linear land parcels. ③ Under the constraints of "baseline control-layered control-indicator control," with the increase in stock renewal speed,the expansion of newly predicted construction land in different scenarios remains within the range of planned control. The scale of expansion for newly predicted construction land is reduced,and it is concentrated in the West,South,and Southeast of Jiangyin city. This transition aligns with the growth boundaries and land layout structure designated in the master planning outline. In different scenarios,stock land renewal is dominated by industrial land,followed by rural construction land. ④ In scenarios (d) and (e),industrial renewal tends toward saturation,achieving overall balanced growth,serving as a key reference for future land use pattern development in Jiangyin City.