Assessment of sediment quality in two important areas of mariculture in the Bohai Sea and the northern Yellow Sea based on acid-volatile sulfide and simultaneously extracted metal results

► AVS and SEM contents were first obtained in Laizhou Bay and Zhangzi Island sediments. ► Zn and Cu contributed most to the concentrations of SEM. ► Grain size, TOC and water content co-affected the behaviors of acid extracted metals. ► [SEM]/[AVS] indicated that the quality of sediments were in satisfactory condition.