Spatial Characteristics of Mean Particle Sizes, Organic Carbon, and Pore-water Salinity in the Surface Sediments of the Ujeon Tidal Flats, Jeungdo, Sinangun, West Coast of Korea

Abstract

The Getbol Korean Tidal Flats (including Ujeon Tidal Flats), recognized for their distinctive geological formations and ecological importance, were designated a UNESCO World Natural Heritage site on 26 July 2021, underscoring their significant conservation value. This study aims to enhance understanding of the Ujeon Tidal Flats, Jeungdo, Sinangun, West Coast of Korea. In June 2023, the research analyzed 124 surface sediment samples for Total Organic Carbons (TOC) content, sediment mean particle sizes, dry bulk density, porosity, water content, and pore-water salinity, etc. Using drone technology and a digital elevation model (DEM), orthometric heights were determined at sampling sites. Sedimentary facies ranged from coarse sand to clay. The TOC content averaged 0.44% (range 0.00–1.42%) with C/N ratios averaging 12.5 (range 9.9–30.3). Mean grain size, pore-water salinity, and orthometric height averaged 4.98 Φ (range 1.06–9.75 Φ), 48.09 psu (range 0.00–93.82 psu), and 1.27 m (range from –0.38 to +3.15 m), respectively. Spatial variations in TOC showed higher concentrations in muddy areas and lower concentrations at sandbars, closely linked to sediment texture. Areas with higher clay and mud content had increased TOC levels. The study provides valuable coastal management and conservation insights, particularly in addressing sedimentation changes along Jeungdo, Shinangun's West Coast of Korea.