Response of marine microalgae,heterotrophic bacteria and their relationship to enhanced UV-B radiation

Ozone depletion in the stratosphere has enhanced solar UV-B radiation reaching the Earth surface and has brought about significant effects to marine ecosystems. The effects of enhanced UV-B radiation on marine microalgae, heterotrophic bacteria and the interaction between them are discussed. The effects on marine microalgae have been proved to occur at molecular, cellular and population levels. Enhanced UV-B radiation increases microalgal flavonoid content but decreases their chlorophyll content and pho-tosynthesis rate; this rachation induces genetic change and results in DNA damage and change of protein content. There have been fewer studies on the effects of UV-B radiation on marine heterotrophic bacteria. Establishment of a nucroalgal ecological dynamic model at population and community levels under UV-B radiation has gradually become a hotspot. The effects of enhanced UV-B radiation on microalgae communities, heterotrophic bacterial populations and interaction between them will become a focus in the near future. This paper will make an overview on the studies concerning the effects of enhanced UV-B radiation on marine microal-gae and heterotrophic bacteria and the interaction between them.