Translator Disclaimer
1 March 2006 Sublethal Exposure to UV Radiation Affects Respiration Rates of the Freshwater Cladoceran Daphnia catawba
Author Affiliations +
Abstract

We examined the effects of UV radiation (UVR) on metabolic rates of the freshwater cladoceran Daphnia catawba. We exposed D. catawba to UVB for 12 h in a lamp phototron at levels of 2.08 and 4.16 kJ m−2 both with and without concomitant exposure to UVA and visible photorepair radiation (PRR). We also included a group that received PRR only and a dark control group. Respiration rates were measured for 6 h following exposure. Respiration rates increased by 31.8% relative to the dark control at the lowest level of UVB stress (2.08 kJ m−2 UVB with PRR), whereas respiration was inhibited by 70.3% at the highest stress level (4.16 kJ m−2 UVB without PRR). Survival rates in the group that received PRR only and the group exposed to 2.08 kJ m−2 and PRR were not significantly different from that in the control group; however, the survival rate was reduced for all other UVR exposures. We hypothesize that enhanced respiration rates reflect energetic costs related to repair of cellular components damaged by sublethal levels of UVR. Increases in respiration rate of the magnitude we found in our experiment could significantly reduce energetic reserves available for growth and reproduction, especially in cases where these costs are incurred repeatedly during a series of days with high levels of UVR.

Janet M. Fischer, Peter A. Fields, Peter G. Pryzbylkowski, Jaclyn L. Nicolai, and Patrick J. Neale "Sublethal Exposure to UV Radiation Affects Respiration Rates of the Freshwater Cladoceran Daphnia catawba," Photochemistry and Photobiology 82(2), 547-550, (1 March 2006). https://doi.org/10.1562/2005-08-30-RA-664
Received: 30 August 2005; Accepted: 1 November 2005; Published: 1 March 2006
JOURNAL ARTICLE
4 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top