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The Effects of Site Preparation on the Long Term Growth and Productivity of Interior Douglas-fir and Western White Pine
No full textSilvicultural treatments applied prior to regeneration or during early stages of stand development can affect tree and stand productivity throughout the rotation. Most studies rarely extend measurements beyond the first decade after treatment, limiting our ability to properly assess long-term treatment efficacy. This is especially true in forests of the Inland Northwest. In 1982, a study was initiated on the Priest River Experimental Forest in northern Idaho to test the effects of different mechanical and chemical site preparation treatments on regeneration performance of interior Douglas-fir (Pseudotsuga menziesii var. glauca) and western white pine (Pinus monticola Dougl. ex. D. Don). The study was replicated at two sites: a high elevation site and a low elevation site. Within each site four treatments were replicated 3 or 4 times, including (1) organic horizon removal and mineral exposure (scalping), (2) mixed organic and mineral soil bedding without competition removal, (3) organic soil bedding with chemical competition control, and (4) an untreated control. The objective of the study was to examine temporal trends in tree growth and growth efficiency to determine if tree productivity was substantially altered by the type of site preparation. Data collection occurred in the summer of 2017, 35 years after treatment. Seventy-five trees were destructively sampled to reconstruct patterns of stem height, diameter, and volume growth, as well as estimate growth efficiency at age 35. The combined bedding and herbicide treatment consistently increased cumulative stem size over time compared to the three other treatments, while scalping and bedding treatments at times resulted in decreased growth and productivity compared to the untreated control. Site preparation treatments did not significantly impact tree leaf area or growth efficiency for either tree species compared to the untreated control. Results of these studies provide a mechanistic context for the growth and productivity of P. menziesii and P. monticola in early maturitymasters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2018-0
MOTOR BUS TRANSFER SYSTEM MODELING WITH PSCAD/EMTDC
No full textWhen starting-up or shutting-down a power generator, there is a need to transfer the generator auxiliary load bus, known as motor bus, from the start-up source to the generator or from the generator to the start-up source respectively. In the course of the transfer process, the auxiliary induction and synchronous motors are exposed to electromechanical and electromagnetic forces that could damage them if an improper transfer is performed. There is also a need to avoid paralleling sources that could increase the short circuit levels during faults causing auxiliary equipment damage. Similar but not less important, is the coasting down duration of the motor bus voltage under the open circuit conditions, which is a complex process owing to the fast voltage, frequency and phase angle variations at the motor bus. During the past twenty years, digital power system simulators have seen very significant technological advances on their numerical algorithms. This has allowed them not only to have more exact and sophisticated power system models, but also to include tools to simulate complex protective relays and control systems interactions with the power system simulation. Until a few years ago, such cases were not only difficult to simulate but also time consuming to carry out. The main purpose of this thesis is the modeling of a motor bus transfer case with standard transfer methods. This model allows the power plant protection and control engineers to study and analyze the induction motor transient behavior during a motor bus transfer in order to implement or upgrade their current motor bus transfer schemes and strategies. Secondly to analyze the electromagnetic transient behavior of the induction motor during the motor load transfer process. Simulations were developed and validated to test and analyze the performance of the motor bus transfer model under several power plant’s normal and emergency conditions and the results are discussed.masters, M.S., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Cadmium Uptake in Wheat: Effects of Phosphorus Management, Variety, and Nutrient Uptake Dynamics; Effects of Andic Mineralogy on Aluminum Toxicity in Acidifying Soils
No full textCadmium accumulation in wheat threatens human health. Phosphorus fertilization management may influence cadmium uptake. Extensive research has investigated the effects of phosphorus application in cadmium-contaminated soils, but none have focused on Northern Idaho’s natural soils. To investigate the effects of phosphorus application rate on cadmium accumulation, and on competition between cadmium and zinc for uptake, we conducted a greenhouse experiment applying varying phosphorus rates to spring wheat grown in natural soil. Additionally, relationships in grain and soil metal concentrations from across Idaho were analyzed using principal components analysis and regression modeling. Quintupling the recommended phosphorus rate resulted in a statistically insignificant increase in grain cadmium and did not induce antagonism between zinc and cadmium, indicating that phosphorus management may not be a viable strategy for controlling cadmium uptake in local soils.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2018-0
Coeur d’Alene Lake Relationships: An Interdisciplinary Study of How Two Communities’ Relationships with a Lake Drive Larger Policy Decisions, Disputes and what those Relationships Tell Us about the Proposition of Collaboration
No full textThe purpose of this study is to address unresolved and ongoing disputes concerning Coeur d’Alene Lake between the Coeur d’Alene Tribal community and the non-Tribal lakeshore communities. Specifically, this study posed two research questions: (1) How do the Tribal and non-Tribal communities surrounding Coeur d’Alene Lake view their relationship to the Lake itself? (2) Given the Tribal and non-Tribal communities’ unique relationships to the Lake, are there opportunities for collaboration on Lake issues in the future? An ethnographic interviewing process, transcribing and data reduction revealed themed responses to the research questions. The findings and conclusions support the idea that an examination of the history, worldviews and perspectives of a perceived opposing party in a dispute may lead to either the identification of impediments to collaboration or the facilitation of collaboration through the revelation of understanding, common ground and respect.masters, M.S., Water Resources -- University of Idaho - College of Graduate Studies, 2018-0
The Influence of Biopesticides on Verticillium Wilt in Potatoes
No full textPotato growers in Southern Idaho are searching for alternative ways to control diseases that are both environmentally sustainable and cost effective. The need for alternative approaches to chemical fumigants is critical, given the recent restrictions on chemical fumigants mandated by regulatory agencies. Application of biopesticides is an approach that is becoming more popular in the agricultural industry, but has not been evaluated extensively in potato production systems. A field and greenhouse experiment was conducted over a two-year period at the University of Idaho Parma Research and Extension Center in 2016/2017 to evaluate how these products might impact Verticillium wilt in potato. The field trial consisted of two biopesticide treatments (Bacillus subtilis and Trichoderma asperellum/Trichoderma gamsii) were applied at 4 different rates/timings. Bacillus subtilis rates consisted of 4.7 l/ha for in-furrow, 4.7 l/ha for low rate chemigation, and 9.4 l/ha for high rate chemigation. Trichoderma asperellum/Trichoderma gamsii rates consisted of 350.8 ml/ha for in-furrow, 2.8 kg/ha for low rate chemigation, and 5.6 kg/ha for high rate chemigation. The in-furrow treatment was applied at planting and the chemigation treatments were applied four times throughout the growing season. Soil and stem samples obtained from each of the treatments before the first chemigation and after all the treatments were completed were analyzed using a real-time polymerase chain reaction (qPCR) to measure the amount of Verticillium dahliae and Colletotrichum coccodes present in the soil and stem tissue. Symptoms of early die were rated at two week intervals and values were calculated using the relative area under the disease progress curve (RAUDPC). There were no significant treatment effects of Bacillus subtilis, Trichoderma asperellum/Trichoderma gamsii or fumigation with metam sodium on visual symptoms of early die, total tuber yield or pathogen populations in stem tissue or soil at harvest when compared with the non-treated control. The greenhouse study consisted of four biopesticides including Bacillus subtilis, Trichoderma asperellum/Trichoderma gamsii, Trichoderma virens, and Reynoutria sachalinensis plant extract. Field soil was amended with sphagnum peat moss to establish three levels of organic matter. There were no significant differences among the treatments that would suggest that biopesticides can effectively control Verticillium wilt in potatoes. More research is needed to understand the efficacy of these products on potato pathogens.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2018-0
The Bioenergy Alliance Network of the Rockies: A “Next Generation” Approach to Forest Management
No full textWestern forests have become fuels-laden due to decades of wildfire suppression policy. Fuels-laden forests are now stressed by both the direct and indirect effects of climate change including increased severity and number of wildfires and increasing insect and disease outbreaks due to rising temperatures and drought. Longer and more severe fire seasons are then threatening humans in the expanding wildland urban interface. However, the current American environmental political structure has created gridlock, making forest management policy implementation difficult. In order to address this complex environmental problem, a “next generation” approach to forest management was introduced. The Bioenergy Alliance Network of the Rockies is a multi-faceted Coordinated Agriculture Project funded by the United States Department of Agriculture to address the most recent outbreak of bark-beetles in the western United States by harvesting beetle-killed trees to improve forest health and provide a renewable source of energy. The innovative approach will have the most potential to avoid gridlock in the wildland urban interface where social considerations outweigh ecological concerns.masters, M.S., Environmental Science -- University of Idaho - College of Graduate Studies, 2018-0
Biochemical Factors Effecting The Production of Soy-Free Tofu Prepared Using Yellow Split Peas (Pisum Sativum)
No full textTofu has been a staple source of protein for over a millennium. Tofu is traditionally made from soybeans (Glycine max) because of its high protein and fat content, but with increased pressures towards other legumes, other crops, like are being explored. Some research has been done into the production of soy-free tofu using freeze dried isolates, but there is a paucity of work that look into manufacturer friendly techniques. The purpose of this thesis is to review the effects of unconventional treatments and different formulations on a pea-based tofu in a manner that can be replicated by a manufacturer. Yellow split peas (Pisum sativum) have a protein make up that is functionally similar to soy tofu, but previous work produces pea tofu with low hardness values. An additional pressing step was taken to remove water to increase the firmness prior to pasteurization. Peas lack the amount of fat the soy contains, so a fat added treatment was run as well. Disruption did improve the hardness of the tofu, so did pasteurization. Additional experiments were run to test different heating times, coagulant concentration, and fat concentrations. Biochemical analyses were run to determine the protein functionality as it pertains to parameters of interest to tofu manufacturers. Overall the research determined that peas can be used to make a tofu with similar parameters to that of commercially produced soy tofu.masters, M.S., Food Science -- University of Idaho - College of Graduate Studies, 2018-0
