Impacts of Anthropogenic Structures on Coastal Morphodynamics: A Case Study of Sand Spit Evolution in the Ujeon Tidal Flat, South Korea

Coastal areas undergo various environmental changes due to the construction of artificial structures. This study examines explicitly the Ujeon Tidal Flat, which was significantly impacted by human activities following the construction of the Taepyeong Saltern in 1957. This construction has led to significant alterations in the coastal environment, notably the growth of a sand spit within the Ujeon Tidal Flat. Using a combination of aerial photographs, geographical factors, and spatial and vertical sedimentary characteristics, we propose a comprehensive scenario for the evolution of this sand spit. The analysis indicates that the construction of the Taepyeong Saltern blocked the tidal currents, shifting the coastal dynamics from a tide-dominated to a wave-dominated environment, which facilitated the growth of the sand spit. This transition underscores the substantial influence of geographical and anthropogenic factors on coastal morphology. Our findings suggest that the Ujeon Tidal Flat is evolving toward a closed-type tidal flat, which is expected to lead to a low-energy environment in the future. These insights are critical for informing the plan and implementation of future conservation and management strategies for tidal flats along the western coast of South Korea. This study highlights the importance of continuous monitoring and adaptive management to preserve these vital coastal systems’ ecological and geological integrity.