In the 300 Area of a U(VI)-contaminated aquifer at Hanford, Washington, USA,
inorganic carbon and major cations, which have large impacts on U(VI) transport, change on
an hourly and seasonal basis near the Columbia River. Batch and column experiments were
conducted to investigate the factors controlling U(VI) adsorption/desorption by changing...
Garden-based learning (GBL) with young people has long been viewed as an educational experience capable of teaching numerous types of science content including general science, technology, engineering and math (STEM), as well as discipline specific areas such as biology, horticulture, agriculture and nutrition. However, much of the GBL literature focuses...
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...
Knowledge of post-dispersal seed fates and other regeneration characteristics is
crucial for predicting abundances and distributions of populations and, ultimately,
community species composition and diversity. Seed fate studies, however, are rare
primarily due to the difficulty of determining seed fates and causes of mortality.
This thesis investigated post-dispersal seed fates...
Relations between the diversity of juvenile anadromous salmonids and pool features
were examined in a managed and a pristine watershed in Oregon during the summer of
1990. There were no differences (p>0.05) in pool depth, velocity or pool wood volumes
between streams. However, the pristine system had twice the number...
Ninety-six hour acute toxicity bioassays were employed to
determine the tolerance of juvenile coho salmon to chlorinated
stabilized kraft mill effluent (SKME). In addition the effect of
chlorinated SKME on the growth of juvenile coho salmon in six and
ten day experiments was studied.
Results of the acute toxicity tests...
Wetland prairies of the Willamette Valley, considered among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native species. Because of its historical importance, fire is a top choice of managers for preventing the encroachment of woody species. However, the effects of prescribed burning on present...
Disability is an emerging field within public health; people with significant disabilities account formore than 12% of the US population. Disparity status for this group would allow federal and state governments to actively work to reduce inequities. We summarize the evidence and recommend that observed differences are sufficient to meet...
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...
In this study, we examine salinity stress tolerances of two populations of the invasive species New Zealand mud snail Potamopyrgus antipodarum, one population from a high salinity environment in the Columbia River estuary and the other from a fresh water lake. In 1996, New Zealand mud snails were discovered in...