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- Amphibians -- Habitat -- Oregon -- Portland Metropolitan Area (1)
- Cascade Range (1)
- Catalytic RNA (1)
- Estuaries -- Northwest (1)
- Hydrology -- Washington (State) (1)
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- Life -- Origin (1)
- Monte Carlo method (1)
- Pacific (1)
- RNA -- Research (1)
- Riparian forests -- Oregon -- Portland Metropolitan Area (1)
- Runoff -- Washington (State) (1)
- Shore birds -- Habitat -- Oregon (1)
- Shore birds -- Migration -- Oregon (1)
- Shore birds -- Seasonal distribution -- Oregon (1)
- Snow -- Washington (State) (1)
- Stream ecology -- Oregon -- Portland Metropolitan Area (1)
- Urban ecology (Biology) -- Oregon -- Portland Metropolitan Area (1)
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich
Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich
Dissertations and Theses
This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with …
Site Selection By Migratory Shorebirds In Oregon Estuaries Over Broad And Fine Spatial Scales, Aileen Kilpatrick Miller
Site Selection By Migratory Shorebirds In Oregon Estuaries Over Broad And Fine Spatial Scales, Aileen Kilpatrick Miller
Dissertations and Theses
Many migratory shorebirds rely on estuaries as stop-over sites to refuel during migration, and the loss of stop-over sites is a primary threat to shorebird populations on the West Coast of the United States (e.g. Calidris alpina pacifica, C. mauri). Conservation and research has focused on the largest of these sites; however, smaller estuaries also host thousands of migratory shorebirds. Furthermore, the reasons for site selection are largely unknown. Estuarine inter-tidal microhabitats are non-uniform and both abiotic and biotic factors may serve as predictors of whether an abundance of shorebirds will use a site. I investigated shorebird site selection on …
Where Is The Rain-On-Snow Zone In The West-Central Washington Cascades?: Monte Carlo Simulation Of Large Storms In The Northwest, Matthew John Brunengo
Where Is The Rain-On-Snow Zone In The West-Central Washington Cascades?: Monte Carlo Simulation Of Large Storms In The Northwest, Matthew John Brunengo
Dissertations and Theses
Rain-on-snow (ROS) occurs when warm, wet air moves into latitudes and/or elevations having vulnerable snowpacks, where it can alter water inputs to infiltration, runoff and erosion. The Pacific Northwest is particularly susceptible: winter storms off the Pacific cause locally heavy rain plus snowmelt almost annually, and disastrous flooding and landsliding intermittently. In maritime mountainous terrain, the effects seem more likely and hydrologically important where warm rains and seasonal snowpacks are liable to coincide, in middle elevations. Several questions arise: (1) In the PNW, does ROS affect the long-term frequency and magnitude of water delivery to the ground, versus total precipitation …
Spontaneous Cooperative Assembly Of Replicative Catalytic Rna Systems, Nilesh Vaidya
Spontaneous Cooperative Assembly Of Replicative Catalytic Rna Systems, Nilesh Vaidya
Dissertations and Theses
The RNA World hypothesis proposes a period of time during the origins of life in which RNA molecules were the only source of both genotypes and phenotypes. Although a vast amount of evidence has been obtained in support of this hypothesis, a few critical demonstrations are lacking. A most crucial one is a demonstration of self-replication of RNA molecule from prebiotic soup. Previously in the Lehman laboratory, it has been demonstrated that a 198-nucleotide molecule derived from the Azoarcus group I intron can self-assemble from up to four fragments of RNA via recombination. Furthermore, the covalent full-length molecules are catalytically …