Predicting Land Use Changes in the Guangdong-Hong Kong-Macao Greater Bay Area Under Alternative Scenarios Using the PLUS Model

Investigating land use change under future climate change scenarios is essential for revealing multimodal trajectories of urban development, which provides a scientific foundation for optimizing land resource redistribution and formulating sustainable development policies. This study analyzes the historical land use evolution in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2010 to 2020 and couples the shared socioeconomic pathways (SSPs) and representative concentration pathways (RCPs) framework from CMIP6. Using the patch-generating land use simulation (PLUS) model, land use patterns in the GBA for the period 2030~2050 under multiple scenarios are simulated. The simulation results for 2020 achieve an overall accuracy of 87.76% and a Kappa coefficient of 0.816, indicating reliable performance for projecting future changes. The findings reveal a continuous expansion of built-up land between 2030 and 2050 across all scenarios, with the growth rate ranked as SSP5.85 > SSP2.45 > SSP1.19. In contrast, cultivated land, forest land, and water bodies are projected to decline, with the most substantial reductions occurring under the SSP5.85 scenario. Notably, the SSP1.19 scenario maintains relatively high stability in the structure of cultivated land, forest land, and water bodies. Its spatial configuration aligns with the concept of ‘mountains, rivers, forests, farmlands, lakes, grasslands, and deserts as a community of life’ effectively balancing urban development needs with ecological conservation. Therefore, the land resource configuration under SSP1.19 offers a scientific basis for optimizing territorial spatial planning and supporting resilient development strategies in the GBA.