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Building a Food Web Portfolio: Hydrologic Heterogeneity Creates Food Web Diversity on a Glacial Meltwater Landscape
No full textMeltwater streams fed by glaciers, icefields, and snow frequently have flow, temperature, and biogeochemical regimes distinct from non-meltwater streams. This physicochemical heterogeneity may support a diversity of freshwater food webs in landscapes where meltwater and non-meltwater streams currently co-occur. Additionally, these streams exist along a continuum which may serve as a space-for-time proxy for changes to physicochemical conditions as glacial and snowmelt influence diminishes with climate change. However, there remains a paucity of knowledge about how food webs are assembled on these rapidly changing landscapes. In the following pages, I describe three studies which examine how the structure of food webs supporting Pacific salmon vary between four streams in coastal southeast Alaska: glacier-fed, snow-fed, rain-fed, and one fed by a combination of rain, snow and glacial-melt. I first assess the temporal dynamics and synchrony of abiotic patterns and biomass waves of the trophic base of the food web. I then analyze the community structure and secondary production dynamics of the aquatic invertebrate community at an annual scale. Lastly, I present quantitative flow food web models using trophic-basis-of-production approach to illuminate the pathways of energy flow that support juvenile salmon. Using these approaches, I found that these cryospheric streams vary greatly in the biophysical patterns and community diversity and structuring. These differences, in turn, create distinct trophic pathways that support fish production between stream types with few shared links between and a greater number of resource flows supporting Coho and Dolly Varden in glacial- and snowmelt streams and substantial overlap in rainwater and combined-signature sites. Although glacial meltwater streams may be less productive overall, they support fish via distinct and diverse pathways from non-meltwater streams and contribute to landscape variation and prey community beta diversity is theorized to increase food resilience and stability. This may be especially true for mobile consumers like juvenile salmon which may track different growth opportunities and energy flow pathways across spatially structured food webs. As glacial and snowmelt contributions to surface waters decline, these distinct meltwater food webs are at risk of extirpation, which could leave salmon populations vulnerable to disturbance and may simplify the overall community structure on the landscape.doctoral, Ph.D., Water Resources -- University of Idaho - College of Graduate Studies, 2022-1
Crash Modification Factors for Public Safety Campaigns – A Case Study: The Idaho’s Shift Initiative
No full textThis study examined the potential crash reduction benefits of public safety campaigns aimed to positively impact the traffic safety culture for young drivers. Crash modification factors (CMFs) for State of Idaho’s SHIFT public safety initiative were developed using Idaho specific crash data covering the period from 2014 to 2020. The CMFs developed as part of this project allow the Idaho Transportation Department (ITD) and other local, state, and federal transportation agencies to assess the potential safety benefits of public safety campaigns. Generalized linear negative binomial models were used to develop crash prediction models which were used as safety performance functions to predict the number of crashes had the tested safety measure (public safety campaigns) not been implemented. The previous literature studies show that the negative binomial model appropriately accounts for both the randomness as well as the overdispersion in the crash count data. The models established were only for the total crashes and fatal and severe injury crashes. Specific crash types were not addressed due to insufficient sample size. The results of the Empirical Bayes method used in this study can be summarized as follows: · Public safety campaigns can reduce the crash rates, and particularly amongst the youths of age group 15-19. The analysis showed that there was significant reduction in fatal crashes as well as total crashes for the age group 15-19 by 24.81% and 5.80% respectively. · Similarly, the age group 20-24 and 25-44 had significant reduction in fatal crashes by 20.75% and 16.29% respectively.masters, M.Engr., Civil & Environmental Engr -- University of Idaho - College of Graduate Studies, 2022-1
The Politics of Exclusion: Joining Multiple Streams Framework (MSF) and Social Construction Policy Design (SCPD) to Examine U.S. Immigration Policy
No full textThis dissertation seeks to contribute to the literature on Policy Process, Multiple Streams Framework (MSF), Social Construction Policy Design (SCPD), U.S. Immigration Policy, and Race. It does so by marrying two Policy Process theoretical frameworks. The theoretical frameworks that have been joined are MSF and SCPD. They were joined to create three different Immigration case studies. Each case study results in an analytical contextualization. This dissertation asserts that the two theoretical frameworks are complementary and jointly they enhance our understanding of U.S. Immigration Policy. Moreover, it argues that jointly they are useful analytical contextualization tools, that help us better understand both a policy decision and design, at times revealing hidden messages. Further, their joint analysis revealed that race and or ethnicity were central to each case study and each policy discussed design. Together, they demonstrate inclusion or exclusion to and from the U.S, which was and continues to be dependent on politics and the biased values held by many in congress. This dissertation is novel as it produces some of the first case studies joining Herweg, Zahariadis, and Zohlnh⍥fer's (2018) contemporary conceptualization of MSF with both Schneider and Ingram’s 1993 SCPD typology and their 2019 extended SCPD framework focused on anticipatory and deceptive policy design.doctoral, Ph.D., Politics & Philosophy -- University of Idaho - College of Graduate Studies, 2022-0
Measuring and Modeling Drainage in North Idaho Forest Water Reclamation Facilities
No full textA growing human population requires sustainable options to regulate and dispose municipal wastewater. In northern Idaho, wastewater treatment facilities are permitted by the Idaho Department of Environmental Quality to apply reclaimed wastewater to areas of forest during the growing season. One of the intentions of this land application is to dispose the reclaimed wastewater while protecting the quality of nearby freshwaters. To avoid excess irrigation, the Idaho Department of Environmental Quality provides facilities with monthly hydraulic loading rates. Drainage measurements below the rooting zone provide quantifications of deep soil drainage, allowing for an assessment of drainage patterns during the growing and non-growing season. No drainage occurred throughout two months of the seasonal drought, but large magnitudes of drainage were recorded during the shoulder months of the growing season. To predict drainage in plots where drainage measurements were not possible, we quantified potential drainage in irrigated forests using hydrological models (Hydrus-1D and Water Erosion Prediction Project). Hydrus-1D and Water Erosion Prediction Project were successful at predicting observed and potential drainage during the growing season. There was not a statistically significant difference between the measured monthly drainage data and the predicted monthly drainage values during the growing season. However, the models were less effective or incapable of precise non-growing season drainage estimates. Annual measured drainage at control plots differed from measured drainage at effluent plots at some facilities. There was large variation in annual measured drainage between effluent plots at four of the facilities. As shown through the models, the estimated crop coefficient recommended by the Idaho Department of Environmental Quality is sufficient in avoiding drainage during the growing season in north Idaho forest systems. Potential drainage is predicted to begin following the treatment season and the start of the autumn wet-season. Drainage quantification is a necessary component to calculate the nutrient flux of forests irrigated with reclaimed wastewater. Based on the findings in this study, there is an elevated risk for nutrient leaching to nearby freshwaters with large magnitudes of drainage occurring during the shoulder months of the growing season and throughout the non-growing season.masters, M.S., Environmental Science -- University of Idaho - College of Graduate Studies, 2022-0
Effect of Ground Based Harvesting Equipment on Soil Physical Properties
No full textLogging in the Pacific Northwest is a key driver in local economies that are natural resource dependent. For many communities in the Pacific Northwest, logging is a livelihood that runs back many generations. The 2021 world population is about 7.8 billion human beings. With the population continuing to increase, the housing market is also on the rise, creating additional demands on logging and manufacturing of lumber. Foresters and loggers have responsibilities to steward the forests. This responsibility includes sustainable operations to ensure a future for the timber industry. There is also a major responsibility to sustain the contribution to the world supply of wood products. The environmental responsibilities that come with logging operations are crucial to creating a sustainable environment. One of the primary pieces of equipment used in ground-based logging operations is a rubber-tired skidder. Rubber-tired skidders are large tractors specifically designed to collect and skid timber for harvest and transport to a landing. During the process of harvesting and skidding trees, the forest floor experiences an exponential amount of weight and displacement. This weight causes soil compaction, and the displacement exposes mineral soil. Skidders establish primary skid trails which become heavily compacted causing the soil’s elasticity to diminish. This study examines the change in soil bulk density caused by rubber-tired skidders in different traffic intensities. The need to use rubber-tired skidders will be present and soil disturbance will not be completely avoidable. The recommendation is to limit the use of rubber-tired skidders to designated skid trails following Best Management Practices (BMPs).masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2022-1
Use of Systemic Antibiotics With or Without Topical Nasal Treatments to Clear Mycoplasma ovipneumoniae From Lambs
No full textMycoplasma ovipneumoniae (M. ovipneumoniae) is often carried asymptomatically in the nasal passages of domestic small ruminants worldwide and is commonly associated with chronic respiratory disease. Currently, no antibiotics are labeled for treatment of this bacterium in domestic sheep in the United States. The efficacy of systemic antibiotics with or without nasal flush treatments to clear M. ovipneumoniae in lambs was assessed. The study was conducted in two parts, Cohort I in 2021 and Cohort II in 2022. Yearling Suffolk lambs were identified as positive for M. ovipneumoniae via nasal swab PCR, randomly assigned to different treatments and a positive control group (n=6 animals per group). Pens were spaced 2.9 meters apart during the study. Treatments in Cohort I were as follows: oxytetracycline 20 mg/kg subcutaneously (SQ) once (OXO); oxytetracycline 10 mg/kg intramuscularly (IM) once daily for 5 d (OXD); oxytetracycline 10 mg/kg IM daily for 5 d with a dilute betadine nasal flush daily for 5 d (OXB); oxytetracycline 10 mg/kg IM daily for 5 d with a dilute chlorhexidine nasal flush daily for 5 d (OXC); and positive control receiving no treatment (POS ). In Cohort II, treatments were as follows: lincomycin 5 mg/kg IM every 48 h for 3 doses (LIN); lincomycin 5 mg/kg IM every 48 h for 3 doses with dilute lincomycin nasal flush daily for 5 d (LIF); florfenicol 20 mg/kg IM every 48 h for 3 doses (FLO); florfenicol 20 mg/kg IM every 48 h for 3 doses with dilute florfenicol nasal flush daily for 5 d (FLF); oxytetracycline 10 mg/kg IM daily for 5 d (OXD); and positive control receiving no treatment (POS). Treatment efficacy was evaluated by nasal swab PCR obtained at days 7, 14, 21 and 28 post treatment. Statistical analysis was performed using non-linear mixed effects modeling in R. Response to treatment was evaluated by comparing mean PCR Ct values of each treatment to the Ct values of the POS groups over time, with Ct values classified as ‘Detected’ (Ct ≤36), ‘Indeterminate’ (Ct 36-40), or ‘Not Detected’ (Ct ≥40). In comparison to the Ct values of the POS groups, OXD was the only treatment found to increase (P = 0.003) Ct values overall, indicating a decrease in M. ovipneumoniae genomic material. OXD compared to POS was (P = 0.004) different on d 7, d 14 (P = 0.0005), and d 21 (P = 0.008), but not on d 28 (P = 0.52). Mean Ct values of OXD groups were 31.4 over the course of the study, while mean Ct values of POS groups were 25.3. Ct values of the OXD group decreased over time (d 7= 35.7, d 28=29.6). The OXB group was significant in increasing Ct value compared to the POS groups only on Day 7 (P = 0.034). All other groups showed no detectable response to treatment in comparison to the POS groups overall, nor at any point in time. Although OXD increased Ct values when compared to POS, it did not induce complete response to treatment by achieving Ct values ≥40 in the majority of animals, nor were the Ct values maintained over time. We suspect the decreasing Ct values over the course of the study were related to the animals being re-infected with M. ovipneumoniae because of prolonged exposure to positive group members that did not respond to treatment. Failure to respond to treatment can likely be attributed to variations in M. ovipneumoniae strain type susceptibility and virulence. Complete response to treatment in the majority of the study animals is needed in order to recommend the antibiotic be used to treat animals with clinical disease. Further studies identifying the strain types present in a study cohort, and testing and segregating animals after treatment to prevent re-infection from a positive cohort is warranted.masters, M.S., Animal, Vet & Food Sciences -- University of Idaho - College of Graduate Studies, 2022-0
Beyond Sage-Grouse: Effects of Conifer Expansion and Removal on Fauna in the Sagebrush Steppe
No full textAbstractEcosystems around the world, and the wildlife species that rely on them, have been impacted by changes in the structure and composition of vegetation. Multiple factors may contribute to habitat degradation, but two common factors are invasion by non-native plants and the expansion of native plants beyond their historical ranges. Habitat degradation, defined as a reduction in habitat quality, occurs when altered habitat lowers an individual’s probability of occupying and reproducing in a habitat, either due to increased risk of predation or reduced resources such as food. Therefore, understanding how changes to habitat structure affect distributions of both predator and prey species is an important part of assessing the impact of structural changes on habitat quality. The sagebrush ecosystem of the western United States is one such ecosystem that has been impacted by invasive and expanding plants. Invasions of non-native annual grasses, most notably cheatgrass (Bromus tectorum), and the expansion of pinyon (Pinus spp.) and juniper (Juniperus spp.) into habitat once dominated by sagebrush have impacted wildlife. Changes to plant structure and composition in sagebrush habitat may impact wildlife by altering the availably of resources such as food and cover, leading to changes in the composition of the wildlife community. One species that has been impacted by habitat degradation in the sagebrush steppe is the greater sage-grouse (Centrocercus uropahsianus). Populations of this sagebrush obligate have declined across their range, and conservation efforts, including conifer removal, have been undertaken to support remaining populations. Other groups of species associated with sagebrush cover have received less study, but community dynamics for these species are likely to be affected by altered habitat structure as well. Because the conifer woodland and sagebrush communities feature little overlap in composition, the final outcomes of a stable state transition from sagebrush to conifer woodland are well understood for many species. However, the potential effects of early-stage conifer establishment in sagebrush habitat are under-examined for sagebrush-associatesother than sage-grouse. Beginning in 2019, the Bruneau-Owyhee Sage-grouse Habitat (BOSH) project initiated the removal of conifer within an area of up to 676,000-ha of multiuse land managed by the Bureau of Land Management (BLM) in southwest Idaho. The goal of this management is to improve habitat for sage-grouse populations. However, the BOSH project also presents a unique opportunity to examine the ways in which the presence of conifer in a sagebrush landscape potentially affects population processes for a suite of functional groups. My study examined the dynamics of the songbird and avian predator communities both before and after the removal of ~15,000 ha of juniper. My study also investigated the relationship between small mammals and habitat characteristics, including conifer and shrub structure. Understanding the ways that habitat mediates species distributions and interactions, as well as the consequences of these interactions for the wildlife community, will allow managers to better predict the results of management actions for both sagebrush and juniper woodland-associated species. Avian predators In chapter two of this dissertation, I examine the relationship between habitat characteristics and occupancy of two generalist avian predators, common ravens (Corvus corax) and red-tailed hawks (Buteo jamaicensis). Increased abundances of these two predators have been attributed to human development in sagebrush habitat, and increased area of conifer woodlands have been implicated as a factor that may influence habitat use for avian predators through the addition of nest and perch sites. However, empirical evidence for a causal relationship between conifer expansion in sagebrush habitats and increased abundances of avian predators is lacking. Anecdotal evidence suggests that conifer expansion may affect predator-prey dynamics because survival rates for sage-grouse that use habitat featuring conifers are lower than those for sage-grouse in areas with no conifers. However, structural resources such as trees are not the only factor that may influence habitat use for avian predators. Prey resources may also be an important aspect of habitat quality that influences habitat use. To investigate the importance of structural and prey resources on habitat use by avian predators, we used a Bayesian occupancy analysis to test the effects of habitat characteristics on habitat use by avian predators. Increased conifer cover, especially cover > 20%, was associated with increased occupancy probability for common ravens but not red-tailed hawks. For red-tailed hawks, distance to the nearest cliff was the most influential factor for habitat use. As the distance to the nearest cliff increased, occupancy probability for red-tailed hawks decreased. We did not find support for an effect of prey abundance on habitat use for either species. Small mammals In chapter three of this dissertation, I examined the effects of habitat structure along an invasion gradient for small mammals. Small nocturnal mammals, including mice and voles, are an important component of the ecosystem because they serve as both predator and prey and alter vegetation structure and composition through herbivory and caching behavior. Therefore, changes to species distributions and interactions among species within the small mammal community may have implications for a broad suite of ecosystem functions. We examined small mammal density, survival, and home-range size along a gradient of cheatgrass and conifer establishment for the deer mouse (Peromyscus maniculatus), a generalist omnivore, and the Great Basin pocket mouse (Perognathus parvus), a specialized herbivore. Neither density nor survival for either species was affected by cheatgrass cover. However, the home-range size of deer mice was 2.3 times smaller in areas with high cover of cheatgrass compared to areas with no or low cheatgrass cover. Conifer cover was an important predictor of density for deer mice, as well as survival for both deer mice and pocket mice. Deer mouse density was highest in habitat with 10% conifer cover, but deer mouse density decreased as conifer cover increased beyond 10%. Survival of deer mice decreased as conifer stem density increased, while survival of pocket mice increased as conifer stem density increased. We found evidence of intraspecific effects of density on home-range size for pocket mice. Home-range size for pocket mice was two times smaller in areas with the highest densities of deer mice compared to areas with low deer mice densities. These results suggest that the removal of conifers as part of wildlife management efforts will likely affect community dynamics for small mammals. Songbirds In chapter four of this dissertation, I examined the effect of conifer and shrub structure in sagebrush habitat on the density of shrub-nesting songbirds, as well as the short-term response of shrub-nesting and conifer-nesting songbirds to conifer removal. Studies of the effectiveness of conifer removal to support populations of songbirds associated with sagebrush habitat have yielded weak or unclear results. However, the spatial scale of the response of individual species to conifer in sagebrush habitat has rarely been considered. Further, shrub structure is a critical feature of habitat for shrub-nesting songbirds, so conifer removal alone may not increase the density of shrub-nesting songbirds if existing shrub structure is not adequate. Shrub-nesting songbirds responded to conifer cover at different spatial scales. Brewer’s sparrow (Spizella breweri) density was negatively associated with conifer cover within 500 m, while sage thrasher (Oreoscoptes montanus) density was strongly negatively associated with conifer cover > 5% within 100 m. Conversely, green-tailed towhee (Pipilo chlorurus) density increased as conifer cover within 1000 m increased. Brewer’s sparrow and green-tailed towhee, but not sage thrasher, were positively associated with greater density, volume, and mean height of sagebrush. Following conifer removal, mean density of shrub-nesting species increased compared to the three years prior to conifer removal. Locations where the highest amount of conifer was removed exhibited smaller increases in shrub-nesting songbird density compared to locations where less conifer was removed, suggesting removal of dense conifer may not immediately lead to increased abundance of sagebrush songbirds. The density of conifer-nesting songbirds, which was strongly associated with conifer cover > 20%, increased or was unchanged in areas of remaining conifer woodlands.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2022-0
Can biophysical models of pelagic larval dispersal explain the observed population structure; case studies from the Gulf of Alaska
No full textNumerous marine fish species have a characteristic pelagic larval dispersal stage. Understanding how this life history strategy affects the observed population structure of the adult groups and the adaptive potential of the species as a whole is therefore of paramount importance. In this study, I initially apply RAD-seq genomic analysis to examine the young of the year aggregates of Pacific ocean perch (Sebastes alutus) collected in 2014 and 2015 in the eastern Gulf of Alaska. I discover that these samples, even from the same haul, contain distinct genetic population mixtures indicating pelagic life stage sympatry. I also discover differences in selection strength between the two years, indicating that the maintenance of a portfolio of adaptive alleles may provide resilience of populations to natural environmental variability, where each adult cohort’s genetic composition is influenced by the environmental conditions experienced during their first year at sea. The apparent disconnect between pelagic stage sympatry and adult stage allopatry motivated the development of a stochastic spatio-temporal genetic model to understand the effect of biophysical dispersal on the population structure. Here, I develop the spatio-temporal genetic model utilizing a dispersal matrix and an allele frequency matrix which is then tracked over a number of generations. I then validate the genetic model with a suite of eight synthetic dispersal matrices and examine the inference via isolation by distance regression, STRUCTURE admixture analysis, and principal component analysis. This lead to unique insight into how each of these commonly used inference methods differs in their ability to differentiate among the synthetic candidate models. I then propose a log likelihood model selection framework based on the beta distribution as a viable alternate to determine which of the candidate dispersal models best explain the observed population structure based on pairwise F_ST values. Finally, I demonstrate the application of the newly developed spatio-temporal genetic model to calculate the expected population structure for three fish species in the Gulf of Alaska, namely, Pacific ocean perch (Sebastes alutus), arrowtooth flounder (Atheresthes stomias), and Pacific cod (Gadus macrocephalus). I use a biophysical dispersal matrix based on the Regional Ocean Modeling System (ROMS) and species specific ontogenic life stage behavior combined in a previously developed mode, the Dispersal Model for Early Life History Stages (DisMELS) to calculate the expected genetic differentiation. I then describe the expected population structure for these three species and apply the PCA, STRUCTURE admixture, and IBD regression inference. This is followed by the comparison of Pacific ocean perch and Pacific cod biophysical model based expected population structure and the observed genetic datasets which reconciles previously contradictory studies. I also demonstrate the application of this spatio-temporal genetic model to determine optimal sampling strategy in the log likelihood model selection framework. The results presented here also suggest that the biophysical based dispersal may be the primary driver behind the observed population structure in the marine species with life history strategies characterized by pelagic larval dispersal.doctoral, Ph.D., Bioinformatics & Computational Biology -- University of Idaho - College of Graduate Studies, 2022-0
“If You Want to Change the World, Edit Wikipedia”: Mitigating the Gender Gap and Systemic Bias on Wikipedia
No full textAs a long-time and experienced editor and contributor to the online encyclopedia Wikipedia, the author of this thesis states, “If you want to change the world, edit Wikipedia.” This thesis makes a case for the existence of what has been called the gender gap and systemic bias on Wikipedia, the reality that there are fewer female editors and less content about women, especially biographies, than male editors and content about and for men. This thesis describes the scope of the problem and describes historical reasons for it, insisting that it has been due to Wikipedia’s place in the history of the encyclopedia and Enlightenment-era philosophies and the commoditization of knowledge-building. Finally, this thesis recommends ways to mitigate the effects of Wikipedia’s gender gap and systemic bias, including improvements in research techniques and ways to use the policies that have hindered Wikipedia’s stated goals for both the diversity of volunteer editors and contributors and to the diversity of content in Wikipedia.masters, M.A., English -- University of Idaho - College of Graduate Studies, 2022-0
Arbor Notes February 2022
No full textThis February publication includes the subject headings: Sketching in the Arboretum; Arboretum Barn through the Years; Message from the President; Calendar of Upcoming Events; Arboretum Associates Donor Roll; Report from the Horticulturist; Summer Concert returns to Arboretu