Abstract. Spatiotemporal distributions of dissolved acrylic acid
(AAd) and related biogenic sulfur compounds including dimethylsulfide (DMS)
and dissolved and total dimethylsulfoniopropionate (DMSPd and DMSPt) were
investigated in the Bohai Sea (BS) and Yellow Sea (YS) during summer and
winter. AAd and DMS production from DMSPd degradation and AAd degradation
were analyzed. Significant seasonal variations in AAd and DMS(P) were
observed. AAd exhibited similar distributions during summer and winter;
i.e., relatively high values of AAd occurred in the BS and the northern YS,
and the concentrations decreased from inshore to offshore areas in the
southern YS. Due to strong biological production from DMSP and abundant
terrestrial inputs from rivers in summer, the AAd concentrations in the
surface seawater during summer (30.01 nmol L−1) were significantly
higher than those during winter (14.98 nmol L−1). The average
concentration sequence along the transects during summer (AAd > DMSPt > DMS > DMSPd) showed that particulate DMSP
(DMSPp) acted as a DMS producer and that terrestrial sources of AAd were
present; in contrast, the sequence in winter was AAd > DMSPt > DMSPd > DMS. High values of AAd and DMS(P) were
mostly observed in the upper layers, with occasional high values at the
bottom. High AAd concentrations in the porewater, which could be transported
to the bottom water, might result from the cleavage of intracellular DMSP
and reduce bacterial metabolism in sediments. In addition, the
production and degradation rates of biogenic sulfur compounds were significantly
higher in summer than in winter, and the removal of AAd was primarily
attributed to microbial consumption. Other sources of AAd existed aside from
the production from DMSPd.
Bacterial Metabolism of C1 Sulfur Compounds
