Remobilization of trace metals from contaminated marine sediment in a simulated dynamic environment.
In this study, release and redistribution of sediment bound trace metals due to resuspension were investigated by a lid-driven elongated annular flume (LEAF). The total suspended particulate matters (SPMs) increased significantly in quantity with the raised resuspension energies and varied distinctively in particle size and mineral composition. Except for Cu, Ni, Cd, Pb, and Zn showed an increase in dissolved phase as the resuspension energy increased. Relatively low Cu was observed in dissolved phase whereas it owned the highest original concentration in the sediment. This is primarily due to the very low solubility of Cu sulfide. In comparison to sediment, all metals were evidently enriched in SPMs which primarily contributed to the much more fine particles (silt/clay fraction) contained in the SPMs. Metals enrichment followed the Irving-Williams order of complex stability. However, metals content varied indistinctively in the SPMs among the three selected resuspension levels. The distribution coefficients (K d) exhibited opposite trend with the increasing resuspension level with the exception of Cu. It indicated that physical and chemical characters of sediment such as grain composition, Fe/Mn, and organic matter content may also act as major factors in the release of metals and control their phase distribution in the water column.
CAS Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China. whxu@scsio.ac.cn.
Weihai
W
Xu
Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Xiangdong
X
Li
Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Onyx W H
OW
Wai
Department of Environmental Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA.
Weilin
W
Huang
CAS Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
Wen
W
Yan
D000538:Aluminum Silicates / Q000737:chemistry; D000077215:Clay; D019015:Geologic Sediments / Q000737:chemistry*; D008670:Metals / Q000032:analysis / Q000737:chemistry; D009792:Oceans and Seas; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis / Q000737:chemistry; D012995:Solubility; D014131:Trace Elements / Q000032:analysis / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
D000538:Aluminum Silicates; D008670:Metals; D052638:Particulate Matter; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D014867:Water; D000077215:Clay
Heavy metals; LEAF; Sediment resuspension; Simulated coastal system