퇴적물 교란에 따른 금속 용출 및 환경인자 변화 특성 평가

초록

This study investigated the release characteristics of metals and the variation of environmental parameters in sediments under physical disturbance. Artificially contaminated sediments with two different textures (Loamy sand and Sand) were subjected to mechanical mixing experiments to evaluate the effects of sediment disturbance. The concentrations of eight metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) and environmental factors (pH, dissolved oxygen (DO), dissolved organic carbon (DOC), sulfate, total Fe, Fe2+, Fe3+, suspended solids, electrical conductivity, and oxidation–reduction potential (ORP)) were analyzed in the overlying water and porewater before and after disturbance. Metal concentrations increased in both sediment types with applying a disturbance condition, with a greater rise observed in Sand-type sediment due to its lower contents of organic matter and oxides. The decrease in sulfate and Fe2+, accompanied by an increase in DO and ORP, clearly indicated a transition toward oxidizing conditions after disturbance. Pearson correlation analysis revealed that DO, DOC, Fe, and sulfate were the dominant factors influencing metal mobility. These findings suggest that redox-sensitive environmental parameters among the physicochemical properties of sediments play a crucial role in determining the remobilization of metals during sediment disturbance events.

키워드