Study on the Geochemical Characteristics of Surface Sediments in the Eastern Sea Area of Qingdao

The grain size and major/trace element contents of 242 surface sediment samples from the eastern marine ranching area and adjacent waters of Qingdao West Coast New Area were analyzed to investigate their spatial distribution characteristics and material sources. Results show that surface sediments in the study area comprise 11 types, with sandy silt (sZ) being the most widely distributed. The mean grain size distribution reveals coarser sediments in central and northeastern regions, while finer particles dominate eastern areas. Chemically, sediments are predominantly composed of SiO₂ and Al₂O₃, with trace elements (Li, V, Co, Ni, Mo, Rb, Sr, Ba) showing comparable concentration levels. R-mode factor analysis identified five principal geochemical associations, indicating that fine-grained clay minerals and biological activities primarily govern element distribution. Notably, Sr and CaO exhibit distinct enrichment in marine ranching zones, suggesting that aquaculture operations significantly influence the geochemical characteristics of major/trace elements in this coastal ecosystem. This study demonstrates that marine ranching activities modify sedimentary geochemical signatures through both physical deposition processes and biogeochemical interactions.