Long-term Dynamics of Coastal Dune Landscapes and Floristic Diversity: Insights from a Quarter Century of Resurveys in Castelporziano Presidential Estate

Coastal dunes are dynamic ecosystems along sandy shorelines, uniquely vulnerable to anthropogenic pressures. Traditional monitoring methods, such as field resurveys, are resource-intensive. However, the increasing availability of high-resolution, open-access remote sensing (RS) data offers a cost-effective alternative. This study examines temporal changes in the vegetation of “Castelporziano Presidential Estate” (Natura2000: IT6030084), a strictly protected Mediterranean area. We assessed floristic and landscape dynamics over a 25-year period in three habitat units: Herbaceous Dune Vegetation (HDV), Woody Dune Vegetation (WDV), and Broadleaf Mixed Forest (BMF). Data from 58 resurveyed vegetation plots and coeval satellite imagery were combined to explore whether floristic diversity influences landscape dynamics. Landscape changes were visualized with chord diagrams, while floristic shifts were analysed using rank-abundance curves. Shannon diversity indices were calculated for floristic and landscape diversity across 25, 75, and 125 m buffers, and Linear Mixed Models were applied to assess the influence of floristic diversity on landscape changes. Our findings revealed natural encroachment, vegetation succession and a reduction in artificial cover. Floristic analyses showed marked differences between T0 and T1, particularly in WDV, where Cistus sp. pl. dominance declined significantly. The models (R² > 0.82) demonstrated that relationships between diversity and landscape dynamics differed over time, with negative trends linked to species dominance and positive trends reflecting greater species equipartition. Results confirm that our RS-based approach provides a valuable framework to monitor temporal changes and to suggest conservation measures in protected areas, potentially reducing reliance on time-intensive resurveys.