GEP-based ecological functional zoning and land use drivers in coastal southeast China

Gross ecosystem product (GEP) assesses ecological value, but aggregate growth in urbanizing coastal zones often masks severe structural imbalances. Using the Fujian coast (2003-2023), we integrated spatiotemporal GEP accounting and spatial clustering to quantify land-use drivers and delineate functional zones. We reveal that while GEP doubled, foundational regulating services plummeted from 66.95% to 43.89%. Urban expansion triggered a "value substitution trap", where surging monetized cultural services mathematically masked the physical depletion of regulating capacities, creating a deceptive illusion of sustainability. Based on these structural shifts, five distinct ecological-economic zones were identified. These findings demonstrate that coastal governance must transcend aggregate GEP targets. Implementing spatially differentiated strategies based on internal service structures is essential to mitigate hidden ecological deficits and ensure sustainable coastal planning.