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Quantification of Fuel Loads after Woody Vegetation Reduction Treatments in Pinyon-Juniper Woodlands and Sagebrush Steppe
No full textThis thesis contains two chapters that analyze and summarize fuel loading data after woody plant reduction treatments in sagebrush steppe and pinyon-juniper woodlands in the Intermountain West. Four treatments were implemented at sagebrush-bunchgrass sites in Washington, Oregon, Nevada, and Utah: untreated control, prescribed fire, mowing, and application of tebuthiuron (herbicide). Three treatments were implemented at all of the pinyon-juniper woodlands sites in Oregon, California, Nevada, and Utah: untreated control, prescribed fire, and cutting (lop and lay), with an additional mastication treatment implemented at the Utah sites. Land managers use these treatments to alter fuel beds and increase understory cover by reducing competition from overstory woody plants. The first chapter of this thesis comprises analysis of treatment longevity and changes in surface fuel loads after mastication of pinyon-juniper woodlands in Utah. The second chapter provides summary statistics of fuel loads for the sagebrush steppe and pinyon-juniper treatments at 10 years post-treatment. The summary data presented in the second chapter is intended to be used in a fuel loading guide that will provide data for land managers to use in fire behavior and effects modeling.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-0
A Multi-Faceted Approach to Understanding Notched Net Sinker Manufacture in the Columbia Plateau
No full textCobble tools, including modified stone net sinkers, though abundant in the archaeological record, are understudied and underrepresented in the archaeological literature. Net sinkers are used to weight nets, lines, and traps. Each modified type of net sinker is found in the Columbia Plateau culture area, where evidence of fishing dates as far back as 10,000 BP. Unlike many other fishing tools, net sinkers can point to an intensification of this subsistence practice resulting in the acquisition of larger quantities of fish. While fishing was not the only form of traditional subsistence, it was significant to the diets of the Native inhabitants of the Columbia Plateau and increased over time and across space. Stone fishing technology is also key to recognizing riverine resource procurement since other fishing tools are often made from organic materials and do not survive in the archaeological record. Because notched net sinkers are the most common type found in the Columbia Plateau, this thesis employs analytical research to determine how frequent net sinkers occur across time and space in the southern Plateau. Finally, experimental processes are utilized to determine probable methods for notched net sinker manufacture.masters, M.A., Anthropology -- University of Idaho - College of Graduate Studies, 2019-1
The Effect of Neighborhood Parks on Reported Crime Rates in the Greater San Antonio Area, Texas
No full textBiophilia is a buzzword that is commonly used in society. An increasing body of research points to the benefits of exposure to nature and natural elements. The focus of this study is on how the presence of outdoor parks in a dense urban environment, the greater San Antonio, Texas, area specifically, affects rates of reported crime between 2014 to 2018. Three components make up this investigation. Part one is a macro-level study of six areas, one lower income area with a park and one without, one middle income area with a park and one without, and one upper income area with a park and one without. In each demographic the crime rates in the neighborhood with the park is compared to the one without a park. Across all three income brackets, crime rates decrease in the neighborhood that has the park. The lower income neighborhood shows the greatest significance. Part two is a meso-level examination of the lower income demographic. Twenty neighborhoods with an annual average income of less than $35,000 are compared. Ten of these neighborhoods have parks and ten do not. The results of this study are less conclusive. Evidence indicates that overall, the presence of a park lowers the rate of reported crime, but not enough to achieve significance. Part three is a micro-level examination of the results of part two that focuses just on the neighborhoods with a park. The two neighborhoods that have the highest rates of reported crime are analyzed, as are the two neighborhoods with the lowest crime rates. The observation is that, regardless of demographic factors, the parks in neighborhoods that have the lowest crime rates have the following in common: the park appeals to a multi-generational audience; it can be used at multiple times of the day and year; it is well maintained and has a variety of amenities; it has access for people of all abilities, including those in a wheelchair; there is a good balance of natural elements, such as a river and trees, and man-made amenities. The parks that have higher crime rates share these traits: parks are not well maintained, with portions of the park in total disrepair; the park has a narrow audience that would only be used for specific events; there are few amenities that allow the park to be used in all weather conditions; amenities do not encourage social interaction; and landscaping is limited.masters, M.S., Architecture -- University of Idaho - College of Graduate Studies, 2019-1
Evaluating the Sensitivity of Residential Water Demand Estimation to Model Specification and Instrument Choices
No full textPast studies have estimated residential water with different econometric model choices. Inconsistency in the choice of the price signal, its instruments, and appropriate weather variables have offered qualitatively different estimates of price elasticity — both elastic (>1) and inelastic (1) and the model fit is worse. These results suggest that, so long as temperature variables are included, parsimonious models can provide consistent and efficient estimates, thereby reducing the need for more in-depth measurements (air pressure, humidity, wind speed, for instances) offered by advanced weather stations. Similarly, the choice of price instruments has a negligible impact on elasticity estimates (estimates clustered between -0.77 to -0.69), so long as the set of instruments are valid. These results provide guidance to future researchers for if and how to include different weather metrics while modeling residential water demand. Further, these results also help stakeholders and water managers establish appropriate water price and pricing structure, thereby helping utilities stabilize and generate the revenue along with the proper demand-side management of water.masters, M.S., Agricultural Economics and Rural Sociology (Applied Economics) -- University of Idaho - College of Graduate Studies, 2019-0
Exploring Novel Germplasm and Traits in the National Small Grains Collection Using Genome-Wide Association Mapping Studies
No full textWheat (Triticum aestivum L.), and barley (Hordeum vulgare L.) are two important small grains crops that fulfill important human caloric and nutritional requirements globally. More efficient small grain production systems are required to meet increasing grain demand while minimizing adverse environmental impacts associated with production. The purpose of this dissertation was to identify novel germplasm, traits, and associated quantitative trait loci (QTL) in the National Small Grains Collection (NSGC) through genome-wide association studies (GWAS). The specific objectives were to: 1) identify novel accessions and QTLs associated with dwarf bunt resistance; and 2) characterize barley accessions and identify QTLs associated with drought tolerance and agronomic traits. In objective 1, 292 winter bread wheat accessions were tested for dwarf bunt (Tilletia controversa J.G. Kühn) resistance over a three year trial period in Logan, UT. Ninety-eight accessions were identified as resistant with disease incidence ≤10%, of which 28 accessions were highly resistant with an incidence ≤1% across all three trials. Two genetic loci on chromosome 6D were found to be associated with resistance across three trials. In objective 2, 480 two-row spring barley accessions were assessed for terminal drought tolerance in Aberdeen, ID over two years. Agronomic traits including yield, test weight and protein were measured when the accessions were grown and harvested under regular irrigation and terminal drought treatments. Twenty accessions were highlighted for use in the malting industry and ten accessions were highlighted for use in the food industry. Fifteen genetic loci were associated with at least one agronomic trait across treatments. Accessions and genetic loci identified in these studies can be used to enhance locally adapted wheat and barley cultivars.doctoral, Ph.D., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-1
TIRE-PAVEMENT INTERACTION, EXPERIMENTAL MEASUREMENTS AND MODELING
No full textProviding an adequate level of skid resistance is essential for the safety of motorists. Previous studies demonstrated that the number of crashes is reduced if pavements have sufficient friction, especially in wet conditions. Adequate pavement friction prevents the vehicle from sliding on the pavement surface and provides the grip needed to maintain control over the vehicle. The first phase of this study investigated experimentally the two major friction mechanisms (i.e., adhesion and hysteresis) that contribute to tire-pavement friction. It is postulated that the adhesion between rubber tires and pavements is highly influenced by the surface free energy. However, there are no previous studies carried out to investigate the adhesion between rubber tires and pavements using the surface free energy. The results demonstrated that adhesion friction can be quantified by measuring the surface free energy components of pavement surface aggregates and rubber materials. There was a fair correlation between the adhesive bond energy and the measured coefficient of friction. Higher adhesion between rubber materials and pavement surface provided higher friction. These results provide a fundamental understanding of the mechanisms of rubber-pavement friction and verification of the relationship between adhesion and friction. In addition, there was a strong correlation between friction and rubber rheological properties. Rubber materials with lower modulus provided higher friction compared to those with higher modulus. These results explain the change in skid resistance with temperature throughout the year. The second phase of this study examined different factors that affect skid resistance of pavement surfaces. These parameters included macrotexture, microtexture, and driving speed. The macrotexture of the pavement is related to aggregate gradation of the mix or surface texture pattern. The microtexture is influenced by the roughness of the aggregate particles and their resistance to abrasion and polishing under traffic. This study proposed a new model that can be used to estimate the skid number at a given speed between 20 mph and 60 mph as a function of both macrotexture and microtexture of pavement surface. This model was developed based on the measured frictional characteristics of field test sections. The proposed model can be used if the full-scale friction tester is not available or cannot be used due to the limited length of the test section (e.g., bridge deck). In addition, the model provides a tool to the pavement engineers to ensure adequate skid resistance at various operation speeds during the mix design stage and before the mix is used in the field. A given mix design can be modified to improve its frictional characteristics at early stage which leads to cost savings often spent on the application of surface treatments. The third phase of this study utilized the close-range photogrammetry (CRP) technique to measure the pavement macrotexture and microtexture. Texture parameters were calculated from the collected and analyzed images of the pavement surface. The results of the CRP texture measurements were compared to standard test methods. The CRP texture measurements had excellent correlation with the standard methods; however, the CRP offers simple and accurate, yet inexpensive alternative to the current methods used to measure surface macrotexture and microtexture. In addition, the CRP texture parameters were incorporated in the Persson friction model to predict skid friction as a function of rubber properties. The results demonstrated excellent correlation between measured and predicted friction. This study greatly simplified the texture parameter calculations needed in the Persson friction model with good accuracy. The last component of this study developed a 3D finite element model to investigate the effect of surface characteristics along with rubber properties on the contact stress between the standard skid test tire and pavement surface. Such simulation provides an in-depth understanding of tire-pavement interaction that would require expensive resources to examine in the field. Study parameters included various coefficient of friction, texture (e.g., smooth, and grooved), tire rolling conditions (fully skidding and free rolling) as well as temperature. The developed 3D FE model of the test tire was first validated with laboratory measurements before it was used to examine the effect of the study parameters on tire-pavement contact stresses. The results of the finite element simulations demonstrated that the stress distribution at the tire-pavement interface is non-uniform with maximum values towards the edges of the tire. These findings were consistent with the wearing pattern of the test tire in the field. In addition, the results also demonstrated that the shear stresses increased with surface friction while there was no significant change in the vertical stresses. The grooved surface exhibited higher vertical and shear stresses compared to pavement with smooth texture. The grooved texture is used to improve skid resistance and reduce the noise of pavement surfaces. In addition, temperature was found to have significant impact on the stresses at the tire-pavement interface. The finite element simulation results agreed with the laboratory and field measurements of pavement friction.doctoral, Ph.D., Civil Engineering -- University of Idaho - College of Graduate Studies, 2019-0
Evaluation of Resilient Modulus of Unbound Coarse Materials in Idaho
No full textSeveral transportation agencies are moving towards implementation of the mechanistic-empirical (ME) approach to design and analyze pavement structures. The pavement ME design requires accurate characterization of material properties. The resilient modulus is a primary required input parameter for granular base and subbase layers. This study generated a database for typical unbound materials used in Idaho. Eighteen base and subbase materials were collected from all six districts of Idaho. Preliminary characterization tests (e.g., particle size distribution, Atterberg limits test, soil classification, moisture-density relationships) were carried out to obtain the inherent material properties. In addition, the resilient modulus test was conducted in accordance with AASHTO T 307. In this study, the resilient modulus was calculated using both external Linear Variable Differential Transducers (LVDTs) as well as internal LVDTs. Since the resilient modulus test is time consuming and required trained personnel, in addition the related equipment may not readily available to all transportation agencies, the author assessed the development of predictive models of the resilient modulus as a function of materials properties that are easier to measure. Furthermore, California bearing ratio (CBR) and light weight deflectometer (LWD) tests were conducted on the test materials to explore possible correlations with the resilient modulus. Both CBR and LWD are simpler tests to perform compared to the resilient modulus test. The results of this study demonstrated that the internally-measured resilient modulus was found to be about 24% higher than the externally-measured resilient modulus. The external deformation was higher than the internal deformation due to the end plate and friction effects. The prediction models for the resilient modulus provided good correlations with the measured values. The proposed models can assist transportation agencies to accurately estimate the resilient modulus values for base and subbase materials from basic properties that are easy to measure. The CBR test results showed a fair correlation with the resilient modulus while LWD showed a better correlation with the resilient modulus. Although, these correlations can be used to estimate the resilient modulus, the prediction model of the resilient modulus is recommended over these correlations. The prediction model provides estimates for the resilient modulus at all stress states provided in the AASHTO standard.masters, M.S., Civil Engineering -- University of Idaho - College of Graduate Studies, 2019-0
Elucidating evolutionary processes in three threatened carnivores: genetic substructure, admixture, and cancer susceptibility
No full textAdvanced genomic techniques can be used to understand threats to global biodiversity and to promote ecosystem conservation. Population structure, migration, admixture, and the genetic basis of adaptive variation can be inferred in small, isolated, and declining populations of interest, thereby adding knowledge necessary for appropriate conservation planning. Here, I present three case examples to illustrate genomics’ potential to influence the management of wild populations. First, Tasmanian devils (Sarcophilus harrisii) face a combination of threats to persistence, including devil facial tumor disease (DFTD), an epidemic transmissible cancer. I used RAD sequencing to investigate genome-wide patterns of genetic diversity and geographic population structure. Our results refine the geographic extent of the zone of mixed ancestry and substructure within it. DFTD has spread across all genetic clusters, but recent evidence points to a genomic response to selection imposed by DFTD. Any allelic variation for resistance to DFTD may be able to spread across the devil population, and/or be present as standing variation in both genetic regions. This can inform the management of genetic variation that existed in pre-diseased populations of the species. Second, wolves (Canis lupus) have naturally reestablished in the Pacific northwest region of North America. I used targeted capture sequencing to acquire SNP data from which I inferred population structure and ancestry. The wolves in Washington state represent an admixed population between the inland Northern Rocky Mountain wolf and the coastal rainforest wolf. Given this admixture, conservation status and management could be impacted if other coastal wolf populations continue to decline in size. Third, Catalina Island (SCA) foxes (Urocyon littoralis catalinae) have a high prevalence of ear canal (ceruminous gland) tumors that appear to be associated with inflammation from chronic ear mite (Otodectes) infections. I tested the hypothesis that the remarkably high incidence of tumors in SCA foxes is the result of genetic variants for cancer susceptibility, which have increased in frequency due to isolation and small population size. Using whole-genome sequencing to identify and genotype polymorphic loci, I found that this trait is likely due to many loci across the genome with small effect. These genetic markers may be used for both monitoring and management in this threatened subspecies. Lastly, the study of the genomics of wildlife cancer is undocumented in a concise way. Therefore, I reviewed and synthesized published literature to record recent studies regarding the genomics of cancer, particularly in endangered taxa. Overall, this review, as well as the results of these three case studies, documents ways in which the genomic consequences of a small population size should be considered when managing species of conservation concern.doctoral, Ph.D., Bioinformatics & Computational Biology -- University of Idaho - College of Graduate Studies, 2019-0
Development of Laboratory Detection Protocols for Two Soil-Borne Potato Viruses, Potato Mop-Top Virus and Tobacco Rattle Virus
No full textPotato mop-top virus (PMTV) and Tobacco rattle virus (TRV) are emerging potato pathogens in the United States. PMTV (Pomovirus: Virgaviridae) is a tripartite rod-shaped virus having single-stranded, positive-sense RNA genome encapsidated by a 19.7-kDa capsid protein. The virus is soil-transmitted by plasmodiophoromycete Spongospora subterranea. TRV is a bipartite rod-shaped, single-stranded, positive-sense RNA virus encapsidated by a 23.6-kDa capsid protein. TRV is unique in that RNA-1 can replicate and establish systemic infection in some hosts independent of RNA-2, which encodes for CP, resulting in a ‘capsidless’ virus infection and can present special problems for identification. TRV is also soil-transmitted and vectored by trichodorid nematodes. Both viruses can induce internal necrotic arcs in the flesh of affected tubers, diminishing their quality for processing and fresh market. Visual diagnosis is challenging since both viruses often do not induce symptoms in the foliage, and similar tuber symptoms can be caused by other potato viruses, such as Potato virus Y. Two sensitive and specific laboratory methods were developed for fast and reliable detection of PMTV and TRV in foliar and tuber samples from potato: a triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA), and an immunocapture (IC) reverse transcription (RT)-PCR assay. These TAS-ELISA and IC-RT-PCR methodologies were compared to commercially available detection kits from European diagnostic companies and found to be equal or superior in sensitivity and reliability.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-0