Calibration of Long-Term Change of Heavy Metal Content and the Heavy Metal Background in the Muddy Area of the Middle Yellow Sea Sediments of China

Abstract:

In order to calibration the long-term change of heavy metal content and the heavy metal background in the muddy area of the middle Yellow Sea sediment of China, we combined with the contents of heavy metals (Cu, Pb, Cd, Zn), 210Pb data and the specific surface area (SS) of core A03 from the Huanghai Sea to structure the function models of the heavy metals (Cu, Pb, Cd, Zn) background. With the function models, we calculated the long-term change of the content of the heavy metals in the same SS in core A03. We compared with the content of the heavy metals in the same SS versus the content of heavy metals, showed a obvious demarcation point between them, in 100 cm. The trend is similar with a ideal sediment profile, which means that the starting point of contamination is around 100 cm. Calculated by deposition rate, the sediment age in the 100cm of the core is much older than 200 years. The average value of heavy metal contents under a single specific surface area (SS) below 100 cm without human pollution is taken as the background value of heavy metal Cu, Pb, Cd and Zn at station A03. The background of them are 26.31 mg/kg, 22.11 mg/kg, 0.20 mg/kg and 63.21 mg/kg, respectively. Compared with the nearby sea area, the background of heavy metals is similar. Compared with historical events, the variation characteristics of the heavy metals content under a single specific surface area correspond to major coastal historical events, which means that the estimation reduced the impacts from the provenance and particle characteristics of the sediments on the heavy metals content and that it provides a reference useful for increasing the veracity of evaluation of heavy metals contamination.