Solar ultraviolet radiation and its impact on aquatic systems of Patagonia, South America

Solar ultraviolet radiation (UVR, 280-400 nm) is known to cause a number of detrimental effects in aquatic organisms. The area of Patagonia, which is sometimes under the influence of the Antarctic ozone "hole", occasionally r eceives enhanced levels of ultraviolet B radiation (UV-B, 280-315 nm). Grea t efforts have been put into creating a database for UVR climatology by ins talling a variety of instruments in several localities in the region. Howev er, no comparable effort has been made to determine the impact of normal an d enhanced levels of solar UVR upon organisms. Most of the photobiological research in aquatic systems of Patagonia has focused on determining the eff ects of solar UVR in phytoplankton photosynthesis, DNA damage, and mortalit y, fecundity and repair mechanisms in zooplanktonic species. Some work has also been done with fish larvae and interactions between species at low tro phic levels of the aquatic food web. The results of these studies indicate that in order to assess the overall impact of UVR in a certain waterbody, i t is also necessary to consider other variables, such as changes in cloudin ess, ozone concentrations, differential sensitivity of organisms, and depth of the upper mixed layer/epilimnion. All factors that can preclude or bene fit the acclimation of species to solar radiation.