The impact of UV-B radiation and different PAR intensities on growth, uptake of super(14)C, excretion of DOC, cell volume, and pigmentation in the marine prymnesiophyte, Emiliania huxleyi

The impact of UV-B radiation (280-320 nm) and different PAR (400-700 nm) intensities on growth, uptake of super(14)C, excretion of DOC, cell volume, and pigmentation in the marine prymnesiophyte, Emiliania huxleyi, was studied in a laboratory experiment. In UV-B-exposed algal cultures at UV-B doses >2.7 kJ m super(-2) UV-B sub(BE), changes in incorporation and excretion rate of super(14)C, and indications of DNA damage (in the form of termination of cell division and enlarged cell volume) were observed. Since the UV-B doses used are representative of UV-B doses in the top layer of clear ocean water and E. huxleyi is a common bloom-forming algae with a wide geographic distribution, it is suggested that current UV-B intensities have an impact on primary production and phytoplankton biomass.