Dune morphology and migration in the Nitzanim coastal dunes: Integrating ground penetrating radar and satellite-based...

This study presents a comprehensive examination of coastal dune morphology, migration, and internal structures in Nitzanim, Israel. Our approach integrated Ground Penetrating Radar (GPR) and satellite analysis to understand their evolution and internal architecture. The methodology involved multi-frequency GPR (500 MHz, 250 MHz, and 100 MHz) for subsurface imaging and multi-temporal Landsat, Sentinel-2, and aerial/UAV imagery, with NDVI (Normalized Difference Vegetation Index) analysis for long-term vegetation cover and dune migration monitoring. Results demonstrate a clear trend of decreasing vegetation cover across the study area from 1995 to 2025, which coincides with increased dune mobility and shifts in dune position, with peak migration rates occurring after a localized anthropogenic change: the construction of an artificial lake in 2005. For example, the northern dune's brink line shifted approximately 71 m eastward from its 1995 position, with its southern segment becoming completely exposed by 2015 due to vegetation loss. Concurrently, processed GPR profiles revealed a coherent sequence of quasi-linear internal reflectors within the dune body, with shallow reflections near the crest exhibiting a distinct eastward inclination, suggesting the prevailing direction of past sediment transport. The consistency of these structural elements across different GPR frequencies highlighted the robustness of the multi-frequency GPR methodology employed. Furthermore, the study revealed a relationship between vegetation dynamics and the internal stratification visible in GPR data. While high NDVI values in 1995 correlated with sand accumulation and a visible accumulation line, a reduction in vegetation cover between 2010 and 2025 coincided with an apparent decrease in vertically accreted stratification in GPR profiles, suggesting a relative increase in lateral dune migration during the most recent phase. The combined multidisciplinary approach offers crucial insights into the complex history of dune stabilization, reactivation, and migration in the Nitzanim coastal dunes. It contributes to process understanding in aeolian geomorphology, informing environmental management and conservation strategies in dynamic desert landscapes.