One second GPS collars were deployed on cattle in three different pastures at three separate times during the year. In each riparian pasture the vegetative communities and stream bank edge were digitally mapped using low elevation aerial photographs and checked in the field for accuracy. A 5 m buffer zone...
In this study the impact of episodic events on levels of bioavailable trace metals Zn,
Cu, Cr, Cd, Pb, and As (III) were determined for the lower Willamette River in Oregon.
In addition, a comparison among three alternative methods for estuary sampling was
conducted. Potential adverse human health risk associated...
The Pigeon Guillemot (Cepphus columba) is now the only species of marine bird in Prince William Sound (PWS), Alaska that is listed as "not recovering" on the Exxon Valdez Oil Spill (EVOS) Trustee Council's Injured Resources List and has shown no sign of population recovery. During the 20 years since...
Variable-retention harvesting was proposed to reduce loss of biodiversity and ecosystem processes associated with late-seral Douglas-fir (Pseudotsuga menziesii) forests in the Pacific Northwest. The Demonstration of Ecosystem Management Options experiment was established to test this hypothesis. Analysis presents various challenges to drawing statistical inferences about treatment effects. This dissertation explored...
"... One goal of this document is to synthesize the literature on the effects of mechanical thinning on understory plant species. A second goal is to document the effect of prescribed burning on rare, threatened, or endangered species. We review current literature on studies that address effects of prescribed fire...
This dissertation is a collection of three manuscripts that serve to fill the knowledge gaps and advance methods of detecting the effects of contemporary forest harvesting in experimental catchment studies. While there is a preponderance of studies evaluating the environmental effects of forest harvesting in the western United States, few...
Thesis summarizes interviews with growers residing within the Groundwater Management Area (GWMA) in the Southern Willamette Valley of Oregon. Informal and semi-structured interviews were used to identify perceived impediments and incentives perceived by local farmers in following best management practices related to water quality. Results from the interviews were coded...
Wildfire is a largely terrestrial perturbation broadly recognized as an agent of disturbance and ecological change in forested biomes. Effects of post-fire conditions on biotic components of aquatic systems have been less well-documented, although hypothetically, the two are strongly connected. In fact, the influence of wildfire may be most profound...
Concentrations of selenium (Se), manganese (Mn), zinc (Zn), cadmium (Cd), lead (Pb) and arsenic (As) were measured in the water column, sediment and biota, in conjunction with selected physicochemical data, from representative wetland types at a mining site within Salt Lake County, Utah, USA. The selected field sites included Oolitic...
Caspian terns (Hydroprogne caspia) and double-crested cormorants
(Phalacrocorax auritus) nest in large colonies on East Sand Island in the Columbia
River estuary, the largest known colonies for the two species in the world. Both
species of piscivorous colonial waterbirds have been identified as predators with a
significant impact on the...