THE INFLUENCE OF LIGHT AND TEMPERATURE ON CARBON-SPECIFIC DMS RELEASE BY CULTURES OF PHAEOCYSTIS-ANTARCTICA AND 3 ANTARCTIC DIATOMS

The net carbon specific release of dimethylsulfide (DMS) over 72 h by four phytoplankton species (Nitzschia curta, Thalassiosira tumida, Chaetoceros socialis, and Phaeocystis antarctica) at two temperatures (1 and -1.6-degrees-C), in response to a range of six irradiances (3.5 to 350 mumol m-2 s-1), was investigated in cultures isolated from the Weddell Sea (Antarctica). Under all conditions both mucoid species, P. antarctica and C. socialis, produced more DMS than the other two diatoms. DMS release was higher at low fight conditions for P. antarctica and C. socialis and at high light conditions for T. tumida and N. curta. All species released more DMS at low temperatures. The results demonstrated a temperature dependency of DMS emissions by phytoplankton and corroborate early statements that production of DMS is related to physiological stress.