Craig E. Williamson, Gabriella Grad, Hendrika J. De Lange, Shawna Gilroy, Danielle M. Karapelou
Limnol. Oceanogr., 47(6), 2002, 1844–1848
Climate warming and stratospheric ozone depletion increase temperature and ultraviolet (UV) in mid- to highlatitude ecosystems; however, little is known about the interactive effects of temperature and UV on organisms. We exposed Daphnia catawba, Leptodiaptomus minutus, and Asplanchna girodi to UV-B at four different temperatures: 10, 15, 20, and 25°C. Elevated temperatures increased UV tolerance in D. catawba and L. minutus, species that depend heavily on photoenzymatic repair (PER), but decreased UV tolerance in A. girodi, a species that has less PER. Also, body size in Daphnia decreased with increasing UV dose. These results demonstrate that climate change can alter responses to UV through temperature-mediated effects in aquatic ecosystems, and these effects can be species-specific and dependent on PER ability.