Carbon emissions from land use are a major driver of global climate change, and their accurate characterization and forecastion are essential for regional sustainability. This study integrates a bi-layer programmingBi-layer programming (BLP) framework with the Patch-based Land-Use Simulation (PLUS) model to establish a BLP-PLUS system for Fujian Province, China. Economic benefit and carbon emission are treated as dual optimization objectives, while cultivated land protection and other policy constraints are imposed. A stage-wise optimization strategy is applied under three economic growth scenarios, including low, medium, and high, to generate alternative land allocation schemes. The PLUS modelPLUS model is then used to simulate the spatial evolution of land use and the associated carbon emissions for each scenario. Results show that the proposed framework effectively reconciles economic growth with emission-reduction goals, offering robust policy support and practical guidance for low-carbon land-space planning in Fujian Province.