Acid Volatile Sulfides in Sediments of South Yellow Sea

Abstract

In coastal marine environment, acid volatile sulfide (AVS) is usually one of the most important or reactive phases. We report first set of data on AVS contents in sediments of south Yellow Sea. The AVS contents are less than 11.14 mumol/g (dry sediment weight), with most below 3 mumol/g in the sediment of south Yellow Sea. The average AVS contents of surface sediments (0~10 cm) range from 0.02 mumol/g to 2.30 mumol/g, with an average value of 0.94 mumol/g. There are three zones with high AVS content in sediments and they are dominated by the Yellow River sediments and the old Yellow River transported by coastal current and the Yellow Sea Cold Water Mass, respectively. The AVS content in sediments of these three zones increases initially with burial depth, reaching a maximum at about 13 cm (6 cm for east section), then decreases. One core from the south section, however, shows an exceptionally high AVS content at the surface (4.96 mumol/g) and a minimum at around 7 cm burial depth. This AVS abnormal profile is located at the place where enrichment of methane at shallow layer reported. Except those three high value areas, the AVS content of sediment is very low and does not show significant variations. It is apparent that sediment AVS content is closely related to the organic matter in different sediment environment, since the content of Fe is quite high (average 3.13%) in the sediment of Yellow Sea.