Global atmospheric pollution from chlorofluorocarbons has the
potential of causing significant reductions in the concentrations of
stratospheric ozone. If the production of chlorofluorocarbons were
to continue into the future at the rate prevalent in 1977, the
steady state reduction in total global ozone could be between five
percent to ten...
Artificial substrates colonized by diatoms from Yaquina Estuary, Oregon, were exposed to solar visible radiation and three levels of ultraviolet radiation (UV-B, 290-320 nm). Flow-through microcosms were constructed inside a glasshouse to serve as chambers for the artificial substrates. The artificial substrates were sampled during three spring/summer experiments. Chlorophyll a...
Global increases in ultraviolet-B radiation (UVBR:290-
320 nm) resulting from decreases in stratospheric ozone
concentration have the potential to alter marine primary
production and affect global climate and marine trophic
dynamics. Effects of UVBR on phytoplankton carbon fixation
were determined from open ocean exposure studies conducted
off the coast of...
Anthropogenic releases of trace gases into the
atmosphere are causing a decrease in stratospheric ozone
concentrations and a subsequent increase in solar
ultraviolet-B (UV-B)(280-320 nm) radiation reaching the
earth's surface. The objective of this study was to
determine the acute effects of enhanced UV-B radiation on
the primary production of...
Ultraviolet-B radiation (UV-B) has been suggested as a factor contributing
to global amphibian population declines. While ambient UV-B levels damage the
eggs and embryos of some amphibian species, few studies have addressed how
UV-B affects other life history stages or sublethal responses. My dissertation
focuses on (1) investigations of sublethal...
My thesis explored the effects of and potential mediating mechanisms for an important environmental stressor, ultraviolet-B (UVB) radiation. UVB radiation has negative effects on organisms in both terrestrial and aquatic systems. I used meta-analysis to quantify the effects of UVB radiation on a diversity of aquatic organisms (Chapter 2). UVB...
Plant form is a compromise between resource gathering, reproduction and
the tolerance to physical demands of the abiotic and biotic environment. In
an agricultural field in addition to the natural factors causing stress, humans
also introduce physical and mechanical stresses, and chemical pesticides
into the environment. Many of these factors...
Ultraviolet-B radiation (UVB) is an abiotic stressor in both terrestrial and aquatic systems. The stratospheric ozone layer, depleted due to anthropogenic activities and the cause of elevated UVB at earth's surface over the last four decades, is predicted to recover by 2065. However, UVB levels in aquatic systems may continue...