Optimizing Estuarine Aquatic–Terrestrial Ecotone Landscapes Under Economic–Ecological Trade-Offs: Evidence from the Pearl River Delta

Under the dual pressures of rapid urbanization and climate change, urban expansion in high-density estuarine urban agglomerations has intensified economic–ecological trade-offs in the aquatic–terrestrial ecotone, necessitating land-use planning that reconciles economic growth with ecological protection. Here, we integrated linear programming with the CLUE-S model and incorporated marine–terrestrial integration objectives and typical natural disturbance factors. With this approach, a landscape pattern simulation framework capable of jointly optimizing ecological and economic benefits was developed. The framework was applied to the estuarine aquatic–terrestrial ecotone of the Pearl River Delta. This study drew on a land-use dataset, landscape dynamics, socioeconomic and biophysical drivers, and regional planning constraints to conduct simulation experiments under alternative development scenarios. The model achieved a Kappa coefficient of 0.904. From 2010 to 2020, built-up land expanded rapidly and encroached on ecological space. Simulations indicated that the natural evolution scenario increased fragmentation and ecological conflicts despite economic gains, whereas the sustainable development scenario balanced expansion and protection, reduced forestland fragmentation, safeguarded key ecological spaces, and improved ecological benefits while maintaining economic growth. Ecological benefits in the coastal aquatic–terrestrial ecotone from −0.2 to 0 km increased by 283.3%. The framework embeds land-use dynamics and spatial constraints, providing decision support for territorial spatial planning and ecological security pattern optimization.