S-LUS: a coupled suitability evaluation and land-use simulation framework for digital coast

Scientific planning and management of urban land supply are critical to the high-quality development of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). However, existing research lacks a systematic analysis of the evolution and risks of urban land supply-demand matching under different scenarios. This study integrates land suitability assessment with land-use simulation to develop an urban land supply-demand matching evaluation framework (S-LUS), based on the supply-demand ratio (SDR) and spatial matching degree (SMD). The empirical results show that under the economic development scenario, the supply-demand ratio continues to decline, with the risk of urban land supply-demand imbalance emerging as early as 2060. Under the farmland protection scenario, the decline in the supply-demand ratio slows, but spatial matching continues to deteriorate, and the Macao-Zhuhai-Zhongshan-Jiangmen (MZZJ) urban cluster also faces a risk of supply-demand imbalance. Under the ecological restoration scenario, both the supply-demand matching degree and the supply-demand ratio remain relatively stable, although urban land demand is constrained. These findings reveal the complex dynamics of urban land supply-demand matching in the GBA under different scenarios and highlight the challenges of coordinating multiple objectives, underscoring the necessity of integrating economic development, ecological protection, and land protection goals in land-use policy design.