Release of heavy metals from sediment bed under wave-induced liquefaction.

Sediments in lakes and coasts can release metals into water via static diffusion and especially resuspension. The resuspension under sediment liquefaction may severely affect the concentrations of metals in water. In this study, flume experiments were carried out twice to study the release of two metal combinations (Zn and Pb; Zn and Cu), respectively. Each experiment included three phases: consolidation; non-liquefaction and liquefaction. Results showed that total Zn concentration at liquefaction phase increased by a maximum rate of 26 compared with the consolidation phase. The concentration of particulate Zn at liquefaction phase increased by a maximum rate of 8.30 compared with the non-liquefaction phase. The average concentration of dissolved Zn at the liquefaction phase increased up to 0.24 times from the consolidation phase. Total Zn concentration at the non-liquefaction phase increased by several times compared with the consolidation phase. Metals were homogeneously distributed in the liquefaction layer through wave actions.