The Interactive Effects of Ultraviolet Radiation & Temperature on Pelagic Food Webs

Beartooth Mountains – Wyoming/Montana

The Interactive Effects of Ultraviolet Radiation & Temperature on Pelagic Food Webs

Jasmine Saros, Courtney Wigdahl

July 2007, August 2007

The objective of this research is to understand how temperature and colored dissolved organic matter (CDOM) influence the impact of UV on food webs in lakes. We argue that climate change will regulate UV damage at both the molecular level (by altering temperature), and at the ecosystem level (by altering CDOM). We hypothesize that high UV, low temperature conditions will favor phytoplankton-based food webs while lower UV: temperature ratios will favor bacteria-based food webs, with important consequences for zooplankton, fish, and ecosystem structure and function. A carefully focused set of analytical and experimental approaches will test these hypotheses in the lab, and in the field at different elevations with different UV and CDOM conditions.