Pinyon-juniper woodlands throughout the western U.S. have expanded rapidly following European settlement during the late 19th century. In central and eastern Oregon, western juniper (Juniperus occidentalis var. occidentalis Hook.) encroachment has been previously documented in the sagebrush steppe and upper elevation aspen communities. While these vegetation changes and dynamics have...
I measured responses of free-ranging Rocky Mountain elk (Cervus elaphus) to recreational disturbance at Starkey Experimental Forest and Range, Oregon from April to October, 2003 and 2004. Resting, feeding, and travel activities of 13 cow elk were recorded at 5-minute intervals using Actiwatch™ motion sensors. Elk were subjected to four...
The longshore variability of the coastal response to hurricanes may be examined within the framework of a storm-impact scaling model that compares spatially-variable beach morphology and fluid forcing. The relative elevations of dune height and storm-induced water levels are used to define three impact regimes (swash, collision, and overwash), within...
This thesis develops a geology training manual for the Interpretation staff of Craters of the Moon National Monument and Preserve (CRMO) in southern Idaho. The manual will help the staff convey geologic principles to park visitors who are experiencing a landscape formed by volcanic processes. Basic geology and the most...
Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such as movement of organisms and particulate matter and ways in which anthropogenic disturbance to interface habitats may affect immediate and adjacent...
This thesis considers one of the classical problems in the actuarial mathematics literature, the decay of the probability of ruin in the collective risk model. The
claim number process N(t) is assumed to be a renewal process, the resulting model
being referred as the Sparre Andersen risk model. The inter-claim...
Vegetation provides food for many insects, and many insects serve as food for bats. We investigated the linkages among these three trophic levels in riparian areas throughout the Oregon Coast Range by examining the influence of vegetation cover, composition, and structure on the activity of nocturnal insects and bats, the...
Warming of the terrestrial biosphere due to the anthropogenic addition of carbon dioxide to the earth’s atmosphere is becoming a major focus of scientific inquiry. Predictions of the extent of this warming are hampered by uncertainty in the ability of the earth’s ecosystems to counteract this effect by sequestering carbon...
The growth of foster care, particularly kin foster care has greatly outpaced our knowledge. The purpose of this exploratory qualitative study was to develop a more informed understanding of foster family functioning from the perspective of foster parents. This study examined the experiences of 9 kin and 12 nonkin foster...
Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic and terrestrial habitats. Resource partitioning could facilitate coexistence by allowing each species exclusive access to some resources.
My research examines...
Dramatic declines in several groundfish populations have occurred along
the U.S. West Coast during the last decade (PFMC 1999, Sampson 1997,
Ralston 1998, Bloeser 1999). One problem exacerbating these declines is
insufficient stock assessments, especially for species of west coast rockfish
(Family Scorpaenidae, Genus Sebastes) which comprise the core of...
The fungus Cochliobolus victoriae causes Victoria blight of oats and Arabidopsis and is pathogenic due to its production of a compound called victorin, which induces programmed cell death in sensitive plants. Victorin sensitivity in Arabidopsis is conferred by the dominant gene LOCUS ORCHESTRATING VICTORIN EFFECTS1 (LOV1), which encodes a coiled-coil-nucleotide...
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...
In recent years, there has been renewed interest in black raspberry (Rubus occidentalis L.) breeding. This has been spurred by an increase in black raspberry consumption due to studies that have shown them to be particularly high in anthocyanin content indicating high levels of antioxidants. Present cultivars are ill adapted...
The Amphipoda have been divided into the suborders Gammaridea,
Caprellidea, Cyamidea, Hyperiidea and Ingolfiellidea
(Schram 1986, Crustacea. Oxford University Press, New
York). However, Myers and Lowry (2003) regard the caprellids,
or skeleton shrimps, and the cyamids, or whale lice, as
families Caprellidae and Cyamidae. These distinctive groups
are covered in...
Implementation fidelity (dosage, adherence, quality of delivery, responsiveness, program differentiation) is the degree to which a program was carried out to its original intent. The following three studies examined the implementation fidelity of a school-based health promotion social and character development (SACD) program. The, Positive Action (PA) program was a...
Throughout society, many believe women are not succeeding professionally because of the institutional barriers created by men in the American workforce. However, women may be more competitive with other women than with men, especially when limited job positions are the goal. Competitiveness among women can be explained by a phenomenon...
Fire suppression in the last several decades has resulted in unprecedented accumulations of organic matter on the landscape, leading to an increase in large, intense wildfires. This study investigated the soil microbial community (using phospholipid fatty acid analysis) across recently burned forests on the eastern slope of the Cascade Range...
The effect of primocane management on flowering and fruiting patterns was studied in primocane-fruiting blackberry (Rubus subgenus Rubus, Watson) cultivars 'Prime-Jan'® and 'Prime-Jim'® over two years. Primocanes that were "soft-tipped" (upper 2-5 cm removed) at 1.0 m were compared to un-tipped canes. In both years, soft-tipped primocanes developed 2-3 fold...
This research examines the downstream fining phenomenon as it operates in coastal gravel-bed rivers of Oregon. Downstream fining is a change in bed composition toward smaller sediment sizes in the downstream direction. Changes in stream flow discharge and channel slope affect the rate of bed-load transport, thereby altering the downstream...