Data for relative resistance of estuarine DMS production to ocean acidification in the Yangtze River Estuary

Dimethyl sulfide (DMS) is a climatically relevant sulfur compound, yet its response to ocean acidification in estuaries remains poorly understood. We combined seasonal surveys with ship-based microcosm experiments across the Yangtze River Estuary and adjacent coastal waters to resolve spatial contrasts in DMS cycling and test pH sensitivity. In the coastal waters, pH covaried positively with chlorophyll-a, dimethylsulfoniopropionate, DMS, and DMS yield, while experimental pH reductions of 0.2–0.4 units decreased chlorophyll-a, particulate dimethylsulfoniopropionate, and DMS by 11.8–31.1%, 10.6–24.4%, and 13.8–41.2%, respectively. In contrast, estuarine DMS concentrations, process rates, and microcosm responses showed limited sensitivity to comparable pH declines. These results reveal an estuary–coastal contrast in acidification sensitivity and indicate that DMS production in the Yangtze River Estuary is relatively resistant within the tested pH range, suggesting that acidification–DMS relationships from stable marine waters may not apply directly to highly variable estuarine ecosystems.