Temporal and spatial variations of dimethylsulfoxide in the Bohai Sea and the Yellow Sea

• DMSOd and DMSOp were first determined in the BS and YS in autumn and spring.
• DMSOd and DMSOp concentrations revealed similar seasonal variation patterns.
• The spring average ratio of DMSOp/Chl-a was higher than the autumn value.
• A correlation was observed between the DMSOp and Chl-a concentrations in autumn.

Temporal and spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd and DMSOp) were determined in the Bohai Sea (BS) and the Yellow Sea (YS) during November–December 2011 and May 2012. The average concentrations of DMSOd and DMSOp in the surface water in autumn were 14.6 (6.48 − 52.3) and 10.0 (4.94–31.1) nmol L− 1, respectively, and those in spring were 19.7 (4.84–144) and 25.1 (5.09–108) nmol L− 1. The distributions of DMSOd and DMSOp in the study area were obviously influenced by biological production of phytoplankton. A positive correlation was observed between DMSOp and chlorophyll a (Chl-a) concentrations in the surface water in autumn, suggesting that phytoplankton biomass might play an important role in controlling the distribution of DMSOp in the study area. The spring average ratio of DMSOp/Chl-a was approximately 1.3 times higher than the autumn value, corresponding with the temporal variation in phytoplankton species and biomass between spring and autumn.