From cells to globe: approaching the dynamics of DMS(P) in the ocean at multiple scales

摘要

Major advances in dimethylated sulfur research are being made by approaching its dynamics at multiple scales. At the molecular to cellular level, single-cell techniques in molecular biology allow us to identify the microbes involved in cycling of dimethylated sulfur. Also, we find that dimethylsulfoxide (DMSO) is as ubiquitous as dimethyl sulfoniopropionate (DMSP) in marine plankton, which supports the recent suggestion that both compounds are involved in coping with oxidative stress. At the community level, there is recent evidence for the role of DMSP as a major carrier in organic sulfur transfer and cycling through trophic levels, from phytoplankton to bacteria and to zooplankton through herbivore protozoans. As a consequence, the food web dynamics drive the oceanic emission of atmospheric sulfur. At the ecosystem level, the diverse and intricate effects of the physicochemical setting (light, wind, nutrients) on the oceanic cycling of dimethylated sulfur are being uncovered. A proposed shortcut to detailed understanding of the individual processes presents the depth of the surface mixed layer as the variable that integrates most of the environmental effects and serves for predicting dimethylsulfide (DMS) concentrations, even at the global ocean level. This opens the door to assessing the strength of the DMS biogeophysical system as a climate regulator.