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The Role Of An Invasive Exotic Plant On The Structure Of Aquatic Invertebrate Assemblages: Tamarix In The Southwest United States, Bert Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past 100 years, riparian vegetation communities throughout the Southwest United States have been extensively invaded by Tamarix spp. (saltcedar). Saltcedar derives its common name from its physiological adaptation to excrete salts. The production of Tamarix detritus with associated secondary chemicals may affect the quality of aquatic invertebrate food and habitat resources. An alteration in food and habitat quality may affect the composition and structure of aquatic invertebrate assemblages.

A series of experiments was conducted contrasting aquatic invertebrate assemblage densities, colonization rates, and growth rates associated with Tamarix versus native vegetation, Populus fremontii (cottonwood) and Salix exigua (willow), to …

Three-Dimensional Structure Of Small Strike-Slip Fault Zones In Granitic Rock: Implications For Fault-Growth Models, Kim R. Robeson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three small strike-slip fault zones exposed in granitic rock in the central Sierra Nevada, California, provide field-based data to construct three-dimensional representations of each fault zone in order to compare with the geometries predicted by existing fault-growth models. All three fault zones are nearly vertical, strike -N60°E, and have left-lateral slip. The fault zones range from 60 to 140 m in length and 1 to 12 m wide. Each fault zone consists primarily of parallel to subparallel fracture and fault traces 2 to 56 m long and is separated 25 cm to 7 m by intact rock. One fault zone …

Small Strike-Slip Faults In Granitic Rock: Implications For Three-Dimensional Models, Siang Joo Lim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The geometry and mineralization features of small left-lateral strike-slip faults and associated fractures in Lake Edison Granodiorite of the central Sierra Nevada, California, were examined in order to model the three-dimensional structure of strike-slip faults. These faults, which are reactivated joints, were also examined to determine fault sizes, starting joint size, and evidence for fluid flow.

The associated secondary fractures are usually found in the dilational quadrants of fault-tip regions. The longest fault-segment trace is 32.14 m; the longest joint trace is 22 m. The joint population length (l) is represented by a power-law distribution (l^{-n …}

The Relationship Between Collateral Therapy And The Adult Pedophile's Ability To Advance Through Levels Of Treatment, Julie G. Bennion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the relationship between collateral therapy and the adult male pedophile's ability to advance through levels of treatment. Data from a convenience sample of 27 adult male pedophiles attending therapy at Intermountain Specialized Abuse Treatment Centers were collected for this study. Data were collected from participants' files on 22 independent variables, including the primary independent variable, collateral sessions. The dependent variable was the time it took participants to advance through levels of treatment.

A comparison of measures of central tendency for participants who had and those who had not participated in collateral therapy …

Essays On Scale Economies And Efficiency In Public Education, Kalyan Chakraborty

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Efficiency in public education is a significant issue in the United States. Nationwide, real expenditure per student increased 8% per year between 1960 and 1993, but output as measured by standardized test scores has not increased and in some cases (i.e., the verbal SAT [Scholastic Achievement Test] score) has declined. One explanation is that resources are not being utilized efficiently either in the technical or allocative sense. Also, the issue is important because substantial savings are possible by consolidation of schools and/or districts.

This dissertation explores efficiency by measuring technical efficiency at the school district level from four perspectives. The …

Perceived Fairness And Effectiveness Of Rangeland Collaborative Processes, Kimberly J. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Involvement in collaborative partnerships in natural resource management has become a popular method for natural resource management agencies to collect public input, cope with conflicts, and develop ecosystem management plans. This thesis evaluates various collaborative processes, emphasizing multiple-owner partnerships. Qualitative interviews of 46 landowners in Utah were conducted to reveal concerns and suggestions regarding multiple-owner landscape-level collaborative partnerships. Landowners were concerned about private property rights infringement and losing control of their private land. Landowners were primarily concerned about the fairness and effectiveness of any partnership in which they were involved.

However, they were willing to consider participating if certain procedural …

Analogical Problem Solving: The Differential Impact Of Type Of Training, Amount Of Practice, And Type Of Analogy On Spontaneous Transfer, Dune E. Ives

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research on analogical problem solving has delineated several factors that impact one's ability to spontaneously generate a correct solution strategy to a target problem. These factors include, but are not limited to, type of analogy provided to subjects (i.e., partial versus complete), the level of analogical problem-solving expertise, and the absence of or type of analogical problem-solving training (i.e., teacher-generated or learner-generated) provided to learners.

Recently, researchers have begun to focus on providing solvers with multiple practice opportunities and extending these opportunities over a systematically distributed period of time. When combined with analogical problem-solving training, these factors will augment the …

A Preliminary Evaluation Of The Students' Realizing Educational Potential Program, Frances Y. Tous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Students' Realizing Educational Potential Program (REP) was implemented in the 1993-94 academic year to reduce dropout rates for ethnic minority students at Utah State University. This program is currently funded by a 5-year grant, pending renewal upon demonstration of its effectiveness. A formative evaluation was conducted to determine whether the REP program has accomplished its goals thus far, using 157 minority students. Two levels of analysis were conducted. In the first level, admission index scores, college grade point averages, and the average number of quarters enrolled were compared among three REP and non-REP cohorts. The REP program did not …

The Nonuse Of Figurative Language In Conduct Disordered Adolescents, Mike Berger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship between the literal language and conduct problems among conduct disordered adolescents was examined in 109 subjects. The inability to use figurative language was found to be positively related to ratings of conduct problems. Both the parents' discipline style and nonuse of figurative language were related to conduct problems in conduct disordered adolescents. The possible role of other variables, for example, age, sex, and IQ, was examined. Possible mechanisms that could relate the lack of figurative competence and conduct problems were explored.

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …

All-Sky Measurements Of The Mesospheric "Frontal Events" From Bear Lake Observatory, Utah, Seon-Hee Seo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies of internal gravity waves in the earth's upper atmosphere are of considerable interest. These waves play a very important role in the dynamics of the mesosphere and lower thermosphere (ML T) region where they can transfer large amounts of energy and momentum from the lower atmosphere via wave saturation and dissipation. In particular, small-scale short-period ( < 1 hour) waves of the type regularly recorded by all-sky nightglow imagers operated by Utah State University (USU) are known to be very important contributors. In this thesis attention is focused on a subset of small-scale wave phenomena recently discovered using such image data, the so called "frontal events." Frontal events have distinguishable characteristics from usual short-period ( < 1 hour) gravity waves. The principal characteristics are a well defined leading "front, " which exhibits a sharp change in intensity followed by a coherent wave trail (often extending from horizon to horizon) and relatively high phase speeds ( > 50ms^-1) Another unusual characteristic of "frontal events" is an apparent reversal in contrast of the wave structures as imaged in the hydroxyl (OH) emission (peak altitude - 87 km) when compared with the oxygen (OJ) "green line" (557.7 nm) emission (peak …

Quaternary Amino Acid Geochronology Of The Lahontan Basin, Nevada, And The Chewaucan Basin, Oregon, Jeffrey Bigelow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acid geochronology based on fossil molluscs provides a useful approach to determining the Quaternary history of Great Basin lakes. The Lahontan basin, Nevada, and the Chewaucan basin, Oregon, in the northwest corner of the Great Basin, both contained lakes during the Quaternary. The aim of this study is to improve the Quaternary geochronology in these two basins by measuring time-dependent changes in amino acids preserved in fossil molluscan shells. The abundance of D-alloisoleucine relative to Lisoleucine (All) characterizes the extent of racemization, which increases with age and Ul forms the basis of relative and correlated ages. An age-calibration curve …

Modeling Soil Loss To Determine Water Erosion Risk At Camp Williams National Guard Base, Utah, Kevin P. Bartsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil erosion was assessed at Camp Williams National Guard Base by creating an erosion risk classification map and comparing the erosion impact of disturbance regimes on different hillslopes. Soil erosion does not appear to be a problem for most of Camp Williams.

The Revised Universal Soil Loss Equation was applied using GIS to create a soil erosion risk map for the entire Camp Williams facility. The map indicated where problem areas occurred and showed relative erosion risk, but its lack of quantitative accuracy should be noted. Areas of concern included landscapes with little or no protective vegetation such as roads, …

Development And Validation Of Forest Habitat Models In The Uinta Mountains, Utah, Tracey S. Frescino

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A significant question currently facing environmental managers is how to accurately and efficiently quantify forest diversity and resources. Numerous studies have demonstrated the use of modern spatial analytical tools, such as geographical information systems (GIS), remote sensing devices, and statistical models for predicting the distribution of dominant vegetation cover types. This study examines the ability of generalized additive models (GAMs) to delineate structural diversity in forested ecosystems (specifically the Uinta Mountain Range in Utah) using GIS tools and satellite spectral data, and analyzes the effect of including different forms of satellite data in model construction (i.e., Landsat thematic mapper (TM), …

Late Pleistocene Glacial Chronology Of The Western Ahklun Mountains, Southwestern Alaska, Jason P. Briner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New glacial mapping and 35 cosmogenic ³⁶Cl surface exposure ages, the first ever reported from Alaska, constrain the extent and timing of late Pleistocene glacial fluctuations in the western Ahklun Mountains, southwestern Alaska. Morphometric and soil relative-age data characterize two main drift units deposited during the Arolik Lake and Klak Creek glaciations, named herein. During the Arolik Lake glaciation (early Wisconsin), outlet glaciers emanated from an ice cap over the central portion of the Ahklun Mountains and deposited moraines at or beyond the modern coast. These moraines have slope angles averaging about 11° and crests averaging about 35 m …

Design Of The Guidance, Navigation, And Control Subsystem For The Proposed Firebird Spacecraft, Erin Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Firebird spacecraft is a space mission to gather scientific and physical data on the effects of atmospheric deceleration, commonly called aerobraking. The objective of the Firebird mission is to measure specified aerobraking parameters over a range of reentry velocities to provide a database sufficient to construct and validate mathematical models of such aerobraking mission maneuvers. The Firebird senior design team designed the first spacecraft in the mission series to look at aerobraking at an altitude of 160 kilometers above the surface of the Earth. This paper looks specifically at the design of the subsystem that provides the guidance, navigation, …

On The Model Selection In A Frailty Setting, Jill F. Lundell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When analyzing data in a survival setting, whether of people or objects, one of the assumptions made is that the population is homogeneous. This is not true in reality and certain adjustments can be made in the model to account for heterogeneity. Frailty is one method of dealing with some of this heterogeneity. It is not possible to measure frailty directly and hence it can be very difficult to determine which frailty model is appropriate for the data in interest. This thesis investigates three model selection methods in their effectiveness at determining which frailty distribution best describes a given set …

Fuels Inventory And Appraisal In Intermountain Quaking Aspen (Populus Tremuloides) Communities, Janet A. Beales

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field research was conducted in quaking aspen, Populus tremuloides Michx., communities. Fifty-one plots were established in seven major locations in the Bear River Range of northern Utah. The locations inventoried were divided into two age classes: young aspen (under 70 yr) and old aspen (over 70 yr). Custom fuel models were developed for each age class and the data were analyzed for relationships between fuel loads and other measurable factors, including: basal area, average diameter at breast height (d.b.h.), fuel depth, litter loads, tree regeneration, shrub loads, herbaceous loads, slope, tree height, aspect, percent aspen in the plot, grazing intensity, …

Management Of Microbial Nitrate Production In Agricultural Soils, Wei Shi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrate (NO₃^-) is of central importance in the internal soil nitrogen (N) cycle. While animal wastes and nitrification inhibitors have been used in modern agriculture for decades, their effects on soil NO₃^- concentrations in relation to microbial NO₃^- production have not been well characterized. The objective of this research was to determine microbial NO₃^- production in relation to ammonium (NH₄⁺) availability and nitrifier population activity in agricultural soils receiving animal wastes or nitrification inhibitors.

Several laboratory and field studies assessed the impacts of variously treated dairy wastes and …

Predicting Transpiration Rates Of Hydroponically-Grown Plant Communities In Controlled Environments, Oscar Monje

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Canopy transpiration is a major factor determining crop evapotranspiration and energy budgets. Unfortunately the development of robust models of canopy transpiration is hindered by a lack of reliable data due to the difficulties of making canopy-scale measurements. However, measurements of canopy water vapor and carbon fluxes via gas exchange techniques are possible in controlled environments. Simultaneous measurements of transpiration, photosynthesis, and canopy temperature were made in wheat and soybean communities. These data were used to calculate chamber aerodynamic and canopy stomata! conductances, and to model the response of canopy transpiration to CO₂concentration and vapor pressure deficit. Canopy stomata! …

Channel Narrowing Of The Green River Near Green River, Utah: History, Rates, And Processes Of Narrowing, Tyler M. Allread

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous scientific research has documented channel narrowing on the Green River near Green River, Utah, but the exact timing, rates, and causal mechanisms of that narrowing have been the source of disagreement in the scientific literature. This thesis demonstrates that the Green River has narrowed in two separate periods during the last 100 years. The narrowing is driven primarily by changes in the hydrologic regime and not by the invasion of saltcedar. The channel narrowed between 1930 and 1938, when a shift from wetter than normal conditions to a period of draught led to a reduction in river discharge. Channel …

Frequency And Perception Of Mathematics Activities In Family Child Care And Parent-Child Routines, Annette Kari Eddy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study examined the frequency of preschool mathematics activities at home and in the family child care setting. Provider perception and parent perception of the activities were also surveyed. Twenty-one family child care providers, 38 parents, and 42 preschool children participated in the study. Providers and parents participated in a telephone interview in which they completed either the Day Care Activities Checklist (DAC) or the Parent/Child Activities Checklist (PCAC). Research assistants administered the TEMA-2, a mathematical assessment suitable for preschool children, to the children in the study.

Family child care providers in this study reported engaging in mathematics activities statistically …

The Geomorphic Basis Of Colorado Squawfish Nursery Habitat In The Green River Near Ouray, Utah, Cynthia L. Rakowski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nursery habitat availability is considered a bottleneck to successful recruitment of Colorado squawfish (Ptychocheilus Lucius). Detailed geomorphic studies were conducted in a 1.5-km reach to examine channel response to flows and the geomorphic setting of nursery habitats during a 2-year period. Videography was used to extend relationships in the 1.5-km reach to a longer 10-km reach.

Nursery habitat availability varied yearly with little persistence in location or geomorphic setting of individual habitats for the 2 years of this study. A small number of habitats provided most of the area of high-quality (i.e., deep) habitat, and most of the …

Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fifty-seven Trumpeter swans (Cygnus buccinator) were translocated to the Bear River Migratory Bird Refuge and the Bear River Club Company in northern Utah. The purpose of this effort was to encourage dispersal of the Rocky Mountain population of Trumpeter swans during the winter, and to reestablish a migratory route to southern wintering grounds. I assessed the success of the translocation by evaluating 13 translocation criteria proposed in the literature. In this study I addressed two of these criteria in detail by evaluating habitat quality at the translocation sites and by analyzing potential competitive interactions with Tundra swans ( …

A Hydrogeochemical Study Of The Evolution Of The Headwaters Of The Bear River In The Uinta Mountains, Utah, Michael F. Leschin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The headwaters of the Bear River in the Uinta Mountains of Utah provide a good setting in which to examine the influence of geological materials on stream chemistry. Ionic contributions to the stream-water from soils, vegetation, and the atmosphere generally are sparse enough that they do not mask the geologic contributions. Samples from 37 sites on the four major headwater streams and several minor tributaries were examined geochemically. Data derived from the samples allowed the construction of a hydrogeochemical weathering model specific to the study area. A significant feature of this model is that carbonic acid is the dominant chemical …

Quaternary Bear River Paleohydrogeography Reconstructed From The 87sr/86sr Composition Of Lacustrine Fossils, David P. Bouchard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diverted from its former course to the Pacific Ocean by basalt flows in Gem Valley, Idaho, the Bear River presently flows south into the Bonneville Basin. Constraining the timing of the river's diversion is pivotal to understanding the hydrologic budgets, and thus the climatological implications of the Bonneville Basin lakes. This study employs strontium (Sr) isotopes in mollusc fossils as a tracer of the Bear River water that entered Lake Thatcher, a small, closed-basin lake into which the redirected river flowed en route to the Bonneville Basin. The Sr ratios, combined with the temporal control afforded by amino acid geochronology …

Predicting Resistance And Stability Of Vegetation In Floodplains, David E. Werth Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To calculate flow or depth in a waterway, it is necessary to accurately determine the flow resistance. Past research has made considerable progress in predicting the roughness of nonvegetated uniform channels based on both theoretical and experimental investigations. However, to determine the flow resistance associated with vegetated compound flow channels and floodplains, the effects of the vegetation must be considered.

Recent advancements have led to greater understanding of the effects of partially submerged uniform vegetation in a waterway. However, to accurately determine flow resistance, it is imperative that the effects of both submerged and partially submerged vegetation be taken into …

Studies Of Mid-Latitude Mesospheric Temperature Variability And Its Relationship To Gravity Waves, Tides, And Planetary Waves, Kenneth C. Beissner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperature observations of the middle atmosphere have been carried out from September 1993 through July 1995 using a Rayleigh backscatter lidar located at Utah State University (42°N, 111°W). Data have been analyzed to obtain absolute temperature profiles from 40 to 90 km. Various sources of error were reviewed in order to ensure the quality of the measurements. This included conducting a detailed examination of the data reduction procedure, integration methods, and averaging techniques. eliminating errors of 1-3%. The temperature structure climatology has been compared with several other mid-latitude data sets. including those from the French lidars, the SME spacecraft, the …

Cenozoic Tectonic And Paleogeographic Evolution Of The Horse Prairie Half-Graben, Southwest Montana, Colby J. Vandenburg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Horse Prairie basin (HPB) of southwestern Montana is a complex, east dipping half-graben that contains three angular unconformity-bounded sequences of Tertiary lacustrine, paludal, and fluvial sediments overlying middle Eocene volcanic rocks. The basin is near the eastern edge of the Cordilleran thrust belt, and represents the western half of a larger Paleogene rift basin. Geologic mapping within the Everson Creek and Bannock Pass 7.5 minute quadrangles indicates that five temporally and geometrically distinct episodes of extension characterize the late Mesozoic (?) to Cenozoic tectonic evolution of the upper HPB.

The first episode of extension occurred prior to emplacement of …

Empirical Studies Of Ionospheric Electric Fields, Ludger Scherliess

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first comprehensive study of equatorial- to mid-latitude ionospheric electric fields (plasma drifts) is presented, using extensive incoherent scatter radar measurements from Jicamarca, Arecibo, and Millstone Hill, and F-region ion drift meter data from the polar orbiting DE-2 satellite. Seasonal and solar cycle dependent empirical quiet-time electric field models from equatorial to mid latitudes are developed, which improve and extend existing climatological models. The signatures of electric field perturbations during geomagnetically disturbed periods, associated with changes in the high-latitude currents and the characteristics of storm-time dynamo electric fields driven by enhanced energy deposition into the high-latitude ionosphere, are studied. Analytical …