THE ECOLOGICAL RELEVANCE OF UV-B ENHANCEMENT STUDIES IS DEPENDENT ON TUBE TYPE, TUBE AGE, TEMPERATURE AND VOLTAGE

The irradiance of two types of UV-B fluorescent tubes has been tested at different temperatures and voltages in the laboratory. In a field s tudy the output is measured from tubes of different type and age. The laboratory study shows that the output increases with increasing tempe rature up to a certain temperature. This threshold temperature differs for the two tube types tested. Output increases with increasing volta ge, but the two tube types show different voltage sensitivities. Some necessary precautions when using W-B fluorescent tubes in ecophysiolog ical field experiments are discussed. (C) 1998 Elsevier Science S.A. A ll rights reserved.