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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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The Evolution And Implementation Of An Integrated Approach To Emotionally Focused Couple Therapy: A Case Study, Heather Thompson May 2010

The Evolution And Implementation Of An Integrated Approach To Emotionally Focused Couple Therapy: A Case Study, Heather Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There are a number of advantages to working within an integrated model framework when doing family therapy; however, few therapists test what they articulate as their model against what they really do. The purpose of this study was to test how well one therapist practiced her explicated theoretical integration in a clinical setting. Quantitative and qualitative data were gathered to answer three research questions: the level of adherence to the integration, client change, and change within the integrated model over the course of the study. The sample included three couples; data from 25 video-coded sessions, the Revised Dyadic Adjustment Scale …


Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards May 2010

Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While much has been written about the conflicts, supposed or actual, between logic and faith, science and religion, few accounts of the personal turmoil these conflicts can cause exist. Likewise, many of these nonfiction accounts are written from a distinctly polarized place leaning either to science or faith.

In this thesis, I mix research and history with memoir and a sense of poetry to explore my personal experience with this conflict. At its outset, I hoped for this project to capture my struggle as an orthodox member of The Church of Jesus Christ of Latter-day Saints (LDS) in dealing with …


Comparative Studies On Oxygen Mass Transfer For The Design And Development Of A Single-Use Fermentor, Kristan L. Sorenson May 2010

Comparative Studies On Oxygen Mass Transfer For The Design And Development Of A Single-Use Fermentor, Kristan L. Sorenson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Accurate experimental oxygen mass transfer coefficient, a measure of how quickly oxygen travels from a gas bubble to the bulk liquid, is important for comparing performance and for evaluating the oxygen transfer capability of a fermentor. Delays in probe response and changing gas volumes upon start-up of gassing affect the accuracy of oxygen transfer measurements. To mitigate these inaccuracies, a standard correction procedure for oxygen mass transfer data was established for highly oxygenated, well-mixed fermentation systems. Probe response time correction was generated by applying a second-order response model to dissolved oxygen probes and shown to be effective within 4%. By …


Natural Caregiving Practices And Mothers' Decisions, Shannon L. Searle May 2010

Natural Caregiving Practices And Mothers' Decisions, Shannon L. Searle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mothers care for their infants in various ways, many similar and others more unique, and are influenced by a variety of factors. Influences such as doctors' advice, attending prenatal and child development classes, reading books and magazines, and learning from personal experience contribute to the caregiving decisions mothers make. A type of parenting that focuses on the responsiveness and sensitivity of the mother to the infant's needs is known as natural parenting. Natural parenting involves caregiving practices that are expected to co-occur, such as breastfeeding and frequently maintaining close physical contact with the infant. Two other practices that some mothers …


Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd May 2010

Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased snowmobile use in mountainous terrain has been highlighted as a conservation concern for some Canada lynx (Lynx canadensis) populations. Snow compaction resulting from winter recreation may potentially facilitate access by coyotes (Canis latrans) to habitats used by lynx during winter. Increased interactions could result in either exploitation or interference competition between the two species. Two recent, yet geographically distinct, studies showed contrasting findings regarding coyote movements and their use of snow-compacted trails during the winter. These findings suggest coyote association with snow-compacted trails may be regionally specific and dependent upon ecosystem dynamics and snow characteristics. …


Drivers Of Plant Population Dynamics In Three Arid To Subhumid Ecosystems, Luke J. Zachmann May 2010

Drivers Of Plant Population Dynamics In Three Arid To Subhumid Ecosystems, Luke J. Zachmann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the relative importance of density-dependent and density-independent factors in driving population dynamics is one of the oldest challenges in ecology, and may play a critical role in predicting the effects of climate change on populations. We used long-term observational data to describe patterns in plant population regulation for 57 forb and grass species from three different ecosystems (arid desert grassland, semiarid sagebrush steppe, and subhumid mixed-grass prairie). Using a hierarchical partitioning approach, we (i) quantified the relative influence of conspecific density, heterospecific composition, and climate on temporal variation in population growth rates, and (ii) asked how the relative importance …


Effects Of Professional Development On Infusing Engineering Design Into High School Science, Technology, Engineering, And Math (Stem) Curricula, Zanj Kano Avery May 2010

Effects Of Professional Development On Infusing Engineering Design Into High School Science, Technology, Engineering, And Math (Stem) Curricula, Zanj Kano Avery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the effects of professional development (PD) on the infusion of engineering design into high school curricula. Four inservice teachers with backgrounds in physics, chemistry, industrial education, math, and electrical engineering participated in the 2006 National Center of Engineering and Technology Education (NCETE)-sponsored PD workshops at California State University, Los Angeles (CSULA) and provided three sources of data that were used to answer the research question, "What are the effects of PD on infusing engineering design into high school science, technology, engineering, and math (STEM) curricula"?

Three major themes emerged from the data. …


Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel May 2010

Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last several decades, the use of solitary bees as an alternative to honey bees (Apis mellifera L.) for pollination of commercial crops has increased, in part as a response to ongoing problems faced by commercial honey bee populations. Two solitary bee species have exhibited great commercial potential: the blue orchard bee, Osmia lignaria Say, and the alfalfa leafcutting bee, Megachile rotundata Fabricius (Hymenoptera: Megachilidae). However, growth of O. lignaria and M. rotundata populations is limited in commercial systems, mainly due to low establishment of females at provided nesting sites, possibly due to mortality, dispersal, or other causes. …


Comparison Of Agricultural Area Source Ammonia Gas Concentration And Flux Measurements, Emyrei Reese May 2010

Comparison Of Agricultural Area Source Ammonia Gas Concentration And Flux Measurements, Emyrei Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted in order to compare and evaluate a variety of ammonia (NH3) measurement techniques for determination of ambient gas phase concentration and evaluation of system fluxes. This was accomplished by measuring NH3 emitted from area sources within two dairies, one located in south-central Idaho and another in central California. The measurement techniques utilized included: an array of passive diffusion samplers, a single annular denuder system, a single or paired Fourier transform infrared spectrometer(s) (FTIR), a paired (upwind and downwind) set of differential optical absorption spectrometers (DOAS), and a portable wind tunnel in conjunction with a …


Introduced Sport Fish And Fish Conservation In A Novel Food Web: Evidence Of Predatory Impact, Kevin Lee Landom May 2010

Introduced Sport Fish And Fish Conservation In A Novel Food Web: Evidence Of Predatory Impact, Kevin Lee Landom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addressed a fundamental question in applied ecology and conservation; what is the predatory impact of introduced piscivorous sport fish on imperiled native fish populations? More specifically, which of many introduced species and size-classes represent the greatest threats and should be targeted for control? In order to explore this important question, an integrated analysis of stable isotopes, quantified observed diet analysis, and stable isotope mass-balance models were used to quantify trophic interactions. These tools were used to construct food web models that were then compared to draw inferences regarding the relative contribution of prey fish, including rare native fish, …


Seed Pool Dynamics Of A Great Basin Sagebrush Community In The Context Of Restoration, Kristen M. Pekas May 2010

Seed Pool Dynamics Of A Great Basin Sagebrush Community In The Context Of Restoration, Kristen M. Pekas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Restoration of Great Basin sagebrush communities is often attempted without understanding the potential impacts of either restoration treatments on the seed pool or the seed pool on restoration efforts. In addition, few studies have examined seed pools of the Great Basin and the role of vegetation in structuring seed pool communities. I evaluated soil seed pool dynamics of a Great Basin sagebrush community in a restoration context.

In Chapter 1, I determined the relationship between the compositions of the seed pool and aboveground vegetation and the effect of shrubs (microhabitat effects) and perennial bunchgrass cover (community phase effects) on the …


The Ecological Influences Of Community Trail Use And Physical Activity Among Female Trail Users, Sarah N. Moulton May 2010

The Ecological Influences Of Community Trail Use And Physical Activity Among Female Trail Users, Sarah N. Moulton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite great effort to improve physical activity, little success has come to pass. Due to this, some researchers have shifted from individual approaches to promoting physical activity to multilevel environmental approaches. One of these multifaceted environmental approaches is through community trails. A small body of research has suggested that community trails may be a successful ecological approach to promoting physical activity. However, the research is minimal and inconsistent in supporting effectiveness of community trails for promoting physical activity.

This study sought to examine ecological factors to learn if and how they might influence trail use among women. The ecological factors …


Data Collection And Analysis Methods For Two-Zone Temperature And Solute Model Parameter Estimation And Corroboration, Quinten Glen Bingham May 2010

Data Collection And Analysis Methods For Two-Zone Temperature And Solute Model Parameter Estimation And Corroboration, Quinten Glen Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water temperature directly affects biological and chemical processes of fresh water ecosystems. Elevated instream temperatures are commonplace in the Virgin River of southwestern Utah during summer due to a hot desert climate and high water demands that result in low stream flows. This is of concern since the Virgin River is home to two endangered species, the Virgin River Chub (Gila seminuda) and Woundfin (Plagopterus argentissimus). Efforts to model instream temperatures within the Virgin River have been undertaken to help mitigate elevated instream temperatures including the development of a two-zone temperature and solute (TZTS) model. This …


Optimizing The Physical And Nutritional Environment Of Unleached Root-Zones, Curtis B. Adams May 2010

Optimizing The Physical And Nutritional Environment Of Unleached Root-Zones, Curtis B. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unleached root-zones represent an environmental ideal by eliminating wasteful leaching of nutrients and water. NASA grows plants in space in unleached root-zones, incorporating polymer-coated fertilizer (PCF) into a ceramic media (Turface or Profile). However, lack of growth productivity in space has led to the need for research to improve the nutritional and physical environment of the root-zone, which is the objective of this research. PCF types are diverse in release characteristics and the effects of temperature and substrate water content have not been well characterized. In spite of widespread use, studies on chemical properties and applied studies to verify soil …


Connection, Technology, Positionality: An Inside Look At Women Faculty's Positionality Toward "Connection" And "Technology", Wei Zhai May 2010

Connection, Technology, Positionality: An Inside Look At Women Faculty's Positionality Toward "Connection" And "Technology", Wei Zhai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Women faculty members have been reported rating their level of knowledge and experience in using technologies lower than male faculty members. A closer examination revealed that women faculty members were likely to use technologies that fit into their pedagogy, met students' learning styles and needs, and facilitated their interactions with colleagues and students. So women faculty's choices of particular technologies can be assumed to reflect their particular instructional beliefs and perspectives, represented as a connected approach to learning and teaching. Gender alone is inadequate to explain women faculty's use of technology.

The purpose of this study was to explore women …


Characterizing Ecologically Relevant Variations In Streamflow Regimes, Kiran J. Chinnayakanahalli May 2010

Characterizing Ecologically Relevant Variations In Streamflow Regimes, Kiran J. Chinnayakanahalli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Maintaining the ecological health of streams is vital for sustainable water resources management. Streamflow is a primary factor influencing the structure and function of ecological communities. A quantitative understanding of how stream biota respond to variation in streamflow is required for stream bioassessment. This dissertation focuses on quantifying relationships between streamflow regime and stream macroinvertebrate richness and composition. The contribution comprises statistical models that predict stream macroinvertebrate class from streamflow regime and predict streamflow regime from watershed attributes, and a tool that helps derive watershed attribute variables used in these models.

The dissertation is a collection of three papers. In …


Thioester Hydrolysis Reactivity Of Metal Complexes, James Justin Danford May 2010

Thioester Hydrolysis Reactivity Of Metal Complexes, James Justin Danford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Glyoxalase II is one of two metalloenzymes found in the glyoxalase pathway and is responsible for catalyzing the hydrolysis of a thioester substrate. Its bimetallic active site is found to contain a variety of metal combinations, including Fe(III)Zn(II). A recent report indicates that human glyoxalase II, while containing a Fe(II)Zn(II) center, is catalytically active as a mononuclear Zn(II) enzyme. Detailed mechanistic studies of glyoxalase II enzymes are limited due to uncertainty in the metal ion content of recombinantly prepared samples. The research presented in this thesis is focused on gaining mechanistic insight into thioester hydrolysis promoted by well-characterized metal complexes …


Physiological And Molecular Function Of Hap3b In Flowering Time Regulation And Cold Stress Response, Mingxiang Liang May 2010

Physiological And Molecular Function Of Hap3b In Flowering Time Regulation And Cold Stress Response, Mingxiang Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heme-activated proteins (HAPs) are transcription factors that have multiple roles in plant growth and development, such as embryogenesis, flowering time control, and drought tolerance.

In the present study I found that HAP3b was also involved in controlling response to cold stress. Transcript profiling and gene expression analyses indicated that HAP3b repressed the CBF3 regulon under normal growth conditions. As a result, plants with HAP3b-overexpressed showed decreased survival rates while plants homozygous for the null allele hap3b showed an improved freezing tolerance compared to wild-type plants.

To understand the mechanism of HAP3b in Arabidopsis, i.e. whether it also acts …


Characterization And Physicochemical Modifications Of Polymer Hollow Fiber Membranes For Biomedical And Bioprocessing Applications, Benjamin R. Madsen May 2010

Characterization And Physicochemical Modifications Of Polymer Hollow Fiber Membranes For Biomedical And Bioprocessing Applications, Benjamin R. Madsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hollow fiber membranes (HFMs) formed through phase inversion methods exhibit specific physicochemical characteristics and generally favorable surface and mechanical properties, supporting their use in diverse applications including ultrafiltration, dialysis, cell culture, bioreactors, and tissue engineering. Characterization of, and modifications to, such membranes are important steps in achieving desired characteristics for specific applications.

HFMs subject to gas, irradiation, and chemical sterilization techniques were characterized based on several analytical techniques. It was revealed that these common sterilization techniques can cause inadvertent changes to HFM properties. While these changes may cause detrimental effects to HFMs used in filtration, the methods of sterilization are …


Snowshoe Hare And Forest Structure Relationships In Western Wyoming, Nathan Daniel Berg May 2010

Snowshoe Hare And Forest Structure Relationships In Western Wyoming, Nathan Daniel Berg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Snowshoe hares (Lepus americanus) are a critically important prey species for Canada lynx (Lynx canadensis). Determination of snowshoe hare distribution and abundance is needed in western Wyoming for lynx conservation. We used linear regression to examine the correlations between snowshoe hare density, as determined by mark-recapture estimates, and fecal pellet plot counts on both uncleared and annually cleared plots on the Bridger-Teton National Forest, western Wyoming. We found significant correlations between hare density estimates and fecal pellet counts for both uncleared and annually cleared pellet counts; however the relationship was much stronger for annually cleared pellet …


Evaluation Of Semiochemical Strategies For The Protection Of Whitebark Pine Stands Against Mountain Pine Beetle Attack Within The Greater Yellowstone Ecosystem, Greta Katherine Schen-Langenheim May 2010

Evaluation Of Semiochemical Strategies For The Protection Of Whitebark Pine Stands Against Mountain Pine Beetle Attack Within The Greater Yellowstone Ecosystem, Greta Katherine Schen-Langenheim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-dose verbenone, verbenone plus nonhost volatiles (NHVs), and both semiochemicals in combination with aggregant-baited funnel traps were tested for stand- level protection against mountain pine beetle attack for two consecutive years (2004-2005) at three seral high elevation whitebark pine sites in the Greater Yellowstone Ecosystem. In 2004, two 0.25-hectare treatments comprised of 25 high-dose verbenone pouches or verbenone pouches combined with single baited funnel traps were tested in a push-pull strategy. In 2005, 25 high-dose verbenone and 25 NHV pouches, or verbenone and NHV in combination with baited funnel trap clusters were tested. In both years, treatments were compared to …


Examination Of The Relationship Between Perfectionism And Religiosity As Mediated By Psychological Inflexibility, Jesse M. Crosby May 2010

Examination Of The Relationship Between Perfectionism And Religiosity As Mediated By Psychological Inflexibility, Jesse M. Crosby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship between perfectionism and religiosity is clarified when the adaptive and maladaptive dimensions of both constructs are compared. Literature in both areas implicates the idea of a rigid and inflexible personality style as a possible mediator in the relationship. This investigation examined the relationship of perfectionism and religiosity, using adaptive and maladaptive dimensions, as mediated by psychological inflexibility.

Measures of perfectionism, religiosity, and psychological inflexibility were given to 376 undergraduate college students in an anonymous online survey. Adaptive perfectionism was found to be significantly correlated with adaptive religiosity. Maladaptive perfectionism was found to be significantly correlated with maladaptive religiosity. …


Assessing Quaking Aspen (Populus Tremuloides) Decline On Cedar Mountain In Southern Utah Using Remote Sensing And Geographic Information Systems, Chad M. Oukrop May 2010

Assessing Quaking Aspen (Populus Tremuloides) Decline On Cedar Mountain In Southern Utah Using Remote Sensing And Geographic Information Systems, Chad M. Oukrop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is the most widespread deciduous tree species in North America and aspen ecosystems are highly valued for multiple use, being noted for forage production, understory diversity, wildlife habitat, timber, hydrological assets, and aesthetics. However, aspen communities in the Intermountain Region of the western United States are in evident decline, with certain areas experiencing rapid mortality over the past decade. One location of special interest is the quaking aspen on Cedar Mountain in Southern Utah, USA, an isolated population in the southwestern portion of aspen's geographic range.

Lacking critical information on the location, extent, and …


Internal Design Of Mechanically Stabilized Earth (Mse) Retaining Walls Using Crimped Bars, Bernardo A. Castellanos May 2010

Internal Design Of Mechanically Stabilized Earth (Mse) Retaining Walls Using Crimped Bars, Bernardo A. Castellanos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current design codes of Mechanically Stabilized Earth (MSE) Walls allow the use lower lateral earth pressure coefficient (K value) for designing geosynthetics walls than those used to design steel walls. The reason of this is because geosynthetics walls are less rigid permitting the wall to deform enough to work under active pressures instead of at rest pressures as in steel walls.

A new concept of crimped steel bars was recently introduced. This new type of bar was tested for tension and pullout behavior. Results on tests made on crimped bars show that putting those crimps in the steel bar will …


Common Characteristics Of Young People Who Text: The Connection To Autonomy, Identity And Self-Esteem, Elizabeth M. Davis May 2010

Common Characteristics Of Young People Who Text: The Connection To Autonomy, Identity And Self-Esteem, Elizabeth M. Davis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the relationship between adolescents' use of texting and their level of identity development, cognitive autonomy, and self-esteem. One hundred and nineteen Utah State University students participated in this study by filling out a questionnaire that included a section designed specifically to learn the texting habits of the participants, and also included sections derived from previously existing measures on identity, autonomy, and self-esteem.

The results show statistical significance of age and texting. Participants who were 23 years+ sent significantly less than those participants who were 19-22 years. Areas of gender, identity, and self-esteem were also analyzed. Implications of …


Kindergarten Teachers' Developmentally Appropriate Beliefs And Practices And Their Perceptions Of Children's Kindergarten Readiness: Comparing The Beginning And The End Of The School Year, Rachelle Ernest Wright May 2010

Kindergarten Teachers' Developmentally Appropriate Beliefs And Practices And Their Perceptions Of Children's Kindergarten Readiness: Comparing The Beginning And The End Of The School Year, Rachelle Ernest Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined 180 matched pretest/posttest surveys of kindergarten teachers' perceptions of the transition children experienced upon kindergarten entry. Investigations of changes in the percentages of children perceived as not being ready for kindergarten and percentages of children who were rated as having had a very successful, moderately successful, or difficult transition from the pretest to the posttest were conducted. Additionally, changes in teachers' developmentally appropriate beliefs and practices from the beginning of the school year (pretest) to the end of the school year (posttest) were explored. Further analyses were conducted to find differences and associations between teacher and classroom …


Quantifying Legacy Effects Of Managed Disturbance On Sagebrush Steppe Resilience And Diversity, Julie Ripplinger May 2010

Quantifying Legacy Effects Of Managed Disturbance On Sagebrush Steppe Resilience And Diversity, Julie Ripplinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land-use legacies can affect landscapes for decades to millennia. A long history of shrub management exists in the sagebrush steppe of the Intermountain West where shrub-removal treatments, a type of managed disturbance, have been implemented for over 50 years to reduce sagebrush cover. The assumption behind managed disturbances is that they will increase forage for domestic livestock and improve wildlife habitat. However, the long-term effects of managed disturbance on plant community composition and diversity are not well understood. We investigated the legacy effects of three common types of managed disturbance (chemical, fire, and mechanical treatments) on plant community diversity and …


Ecology And Seasonal Habitat Use Patterns Of Columbian Sharp-Tailed Grouse In Northern Utah, Ron D. Greer May 2010

Ecology And Seasonal Habitat Use Patterns Of Columbian Sharp-Tailed Grouse In Northern Utah, Ron D. Greer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus: hereafter sharp-tailed grouse) populations have been declining. These declines have been attributed to a number of factors, including habitat loss due to agriculture, habitat fragmentation, overgrazing by livestock, and the loss to fire.

To gather information about their status in northern Utah, I radio-marked sharp-tailed grouse in 2003 (n=15) and 2004 (n=20) in two research areas. The study areas were located on the south end of Cache County and in eastern Box Elder County. In the Cache study area, I monitored 7 males and 1 female in 2003, and 6 males and …


Distributed Hydrological Modeling Using Soil Depth Estimated Based On Landscape Variables From Enhanced Terrain Analysis, Teklu K. Tesfa May 2010

Distributed Hydrological Modeling Using Soil Depth Estimated Based On Landscape Variables From Enhanced Terrain Analysis, Teklu K. Tesfa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spatial patterns of land surface and subsurface characteristics determine the spatial heterogeneity of hydrological processes. Soil depth is one of these characteristics and an important input parameter required by distributed hydrological models that explicitly represent spatial heterogeneity. Soil is related to topography and land cover due to the role played by topography and vegetation in affecting soil-forming processes. The research described in this dissertation addressed the development of statistical models that predict the soil depth pattern over the landscape; derivation of new topographic variables evaluated using both serial and parallel algorithms; and evaluation of the impacts of detailed soil …


Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv May 2010

Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hierarchy of biological organization, from molecules to ecosystems, describes the relationships among various biological systems. Of particular interest is assessing how the factors that primarily determine the nature of one hierarchical level also have transcendent qualities that affect the ecology and evolution of higher hierarchical levels. The goal of this dissertation was to use a bottom-up approach to examine the transcendent effects of two factors that strongly determine the nature of their associated level of biological organization. The first, phenotypic plasticity, is a primary factor that determines the phenotype of an individual. The second factor, genetic diversity, largely determines …