Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
The Role Of A Beaver In Shaping Stream Channel Complexity And Thermal Heterogeneity In A Central Oregon Stream, Florence Consolati Machen
The Role Of A Beaver In Shaping Stream Channel Complexity And Thermal Heterogeneity In A Central Oregon Stream, Florence Consolati Machen
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
North American beaver (Castor canadensis) alter stream channel morphology, hydrologic processes, and instream temperature regimes, yet there are few data driven studies that investigate the effect of beaver on stream channel complexity and stream temperature regimes across multiple spatial and temporal scales. The use of beaver as a restoration tool is a method at the forefront of watershed restoration, however little is known about the implications of this restoration technique, particularly with regard to its ability to alter stream channel complexity and stream temperature. This thesis addresses two knowledge gaps with the following objectives: to quantify the role …
A Spatiotemporal Mountain Pine Beetle Outbreak Model Predicting Severity, Cycle Period, And Invasion Speed, Jacob P. Duncan
A Spatiotemporal Mountain Pine Beetle Outbreak Model Predicting Severity, Cycle Period, And Invasion Speed, Jacob P. Duncan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The mountain pine beetle (MPB, Dendroctonus ponderosae), a tree-killing bark beetle, has historically been part of the normal disturbance regime in lodgepole pine (Pinus contorta) forests. In recent years, warm winters and summers have allowed MPB populations to achieve synchronous emergence and successful attacks, resulting in widespread population outbreaks and resultant tree mortality across western North America. We develop an age-structured forest demographic model that incorporates temperature-dependent MPB infestations: the Susceptible-Infested-Juvenile (SIJ) model. Stability of equilibria is analyzed as a function of population growth rates, and indicates the existence of periodic outbreaks that intensify as growth rates …
Aligning Conservation Goals And Management Objectives For Bonneville Cutthroat Trout (Oncorhynchus Clarki Utah) In The Logan River, Utah, Harrison E. Mohn
Aligning Conservation Goals And Management Objectives For Bonneville Cutthroat Trout (Oncorhynchus Clarki Utah) In The Logan River, Utah, Harrison E. Mohn
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Rivers are often managed without informed knowledge of how sportfish use different areas of the river to reproduce, and rarely take into account the relationship between fish movement and how they are distributed within the river when making management decisions. The population of native Bonneville cutthroat trout (Oncorhynchus clarki utah) within the Logan River is the largest documented population remaining for this imperiled species, and still maintains extremely high numbers of fish in the upper river. Currently, fishing is not allowed in the upper 20 kilometers of the Logan River watershed during spawning, based on the assumption that …
Intraspecific Variation In The Response Of Elymus Elymoides To Competition From Bromus Tectorum, Rebecca K. Mann
Intraspecific Variation In The Response Of Elymus Elymoides To Competition From Bromus Tectorum, Rebecca K. Mann
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In the western United States, thousands of acres of degraded rangelands are dominated by aggressive invasive species such as cheatgrass (Bromus tectorum), and are seeded by managers with native plants in an attempt to restore species diversity, wildlife habitat, and ecosystem services. There are many options for obtaining seeds of native plants; for instance, they can be collected from the region where restoration is to occur, or they may be purchased through commercial producers. For a given plant species, managers may also select seeds from unique subspecies, cultivars, and populations. Genetic differentiation among these within-species groups can not only affect …