Theses and Dissertations at Montana State University (MSU)
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Item Understanding hydrogeomorphic influences on stream network denitrification and temperature dynamics(Montana State University - Bozeman, College of Agriculture, 2020) Carlson, Samuel Paul; Chairperson, Graduate Committee: Geoffrey PooleThe removal of nitrate from stream networks through the process of denitrification is an important component of local and regional nutrient cycles, but the controls on stream network denitrification rates remain poorly understood. Previous work has demonstrated general effects of stream channel size and nitrate loading rates on network-scale denitrification rates, but has been unable to elucidate connections between the complex environmental template of streams, and resulting denitrification rates. Understanding links between land use and management practices, physical characteristics of streams, and stream denitrification rates is critical to interpreting observed patterns of nitrate in freshwater systems and forming holistic management strategies for reducing the negative effects of elevated nitrate concentrations. To address these critical uncertainties, I developed a stream network simulation model that incorporates the effects of whole-stream aerobic respiration on biotic denitrification demand. This model is applied to a small, subalpine stream network under scenarios designed to explore: 1) the implications of temperature-controlled, network scale patterns of respiration rates on the distribution and overall magnitude of stream network denitrification, and 2) the effect of logging-induced channel simplification on whole network denitrification rates. The first analysis is complimented by an evaluation of controls on stream temperature across this network, revealing the spatially and temporally variable influence of in-network lakes on stream temperatures. Results from the first analysis suggest that reach- and network-scale denitrification rates are strongly influenced by respiration rate and temperature when nitrate supplies are high relative to removal rates, indicating an increased contribution of lower, warmer streams to whole-network denitrification. The second analysis reveals that historical logging has caused a ~30% loss of stream network denitrification capacity, which is manifested as a corresponding reduction in whole-network denitrification rates when nitrate supplies are not limiting. In sum, this work emphasizes the diverse set of factors that influence reach- and watershed-scale biogeochemical characteristics and processes, and suggests that land management actions which influence stream morphology may also alter stream denitrification rates.Item Understanding the role of social values in ranchland management decision-making: collaborative research with Montana ranchers(Montana State University - Bozeman, College of Agriculture, 2017) Soderquist, Lora; Chairperson, Graduate Committee: Tracy M. SterlingMontana's ranching communities are considered socio-ecological systems (SES), a term which recognizes the role of the social component within a land-based whole. This component includes the decision-making process of ranchers, which is critical for building adaptability, resilience, and transformability (ART) for long-term sustainability. A tool for understanding decision-making process is Kolb's Learning styles which explains how decisions are made in three general stages of Feel-Think-Action. The Holistic Management (HM) decision-making framework, follows Kolb's process by providing a working framework for the Kolb's stages. The HM framework is commonly used by ranchers to manage SES dynamics, in ways that include positive SES benefits. Many measures exist for understanding how decision-making influences economic and ecological components of SESs, however, there are few measures or indicators for understanding the role of social values. Therefore, the objective of this study was to determine the extent to which social values identified by a case study group of HM ranchers are used by a general sample of ranchers. This project used a two-part, participatory collaborative action research -- exploratory mixed-methods design to learn about the role of social values within ranchland management decision-making. Local knowledge partnered with science-based approaches connects common ground and social capital, leading to increased sustainability of SESs. Five HM ranching practitioners collaborated as case study participants. Discussions with each participant was social value focused, lasted 60-minutes, and was recorded. Collaboratively, 10 social values were identified which were held in common. Using the 10 identified social values from the discussions, a 20-question survey was created which included the 10 identified social values, with an underlying element of ART. The survey was administered to 50 ranchers in Eastern Montana via phone and took each participant approximately 10-12 minutes to complete. It was found that all ranchers use the Kolb's Feel-Think components in relationship to the ten identified social values, and HM case study ranchers were more likely and survey respondents were less likely to take Action on these social values. This research documents the role of social values and ART in ranchland management decision-making in ways that cannot be fully expressed when using conventional metrics.Item Holistic approach to natural resource and human management : a case study of the Himalayan National Parks in Nepal(Montana State University - Bozeman, 1994) Sherpa, Nima Wangchu; Chairperson, Graduate Committee: Clifford MontagneItem A survey of soil properties on five ranches practicing intensive time-controlled grazing in south central Montana(Montana State University - Bozeman, College of Agriculture, 1998) Heyneman, John MelvilleItem An evaluation and documentation of Holistic Resource Management practices on Northern Rocky Mountain ranches(Montana State University - Bozeman, College of Agriculture, 1996) Orchard, Charles E.Item Using holistic management steps towards improving soil and vegetation quality and family resiliency in Mongolia(Montana State University - Bozeman, College of Agriculture, 2014) Dovchin, Badamgarav; Chairperson, Graduate Committee: Cliff MontagneMongolian herders are still practicing traditional nomadic pastoralism as their main source of life. In the last 100 years Mongolians have been experiencing dramatic political and economic change. The democratic revolution in 1990 let the herders own herds, but not the pasture. Livestock numbers increased from 25 to 47 million within last 20 years, all grazing on common land. Due to climatic and grazing practice changes and socio-economic issues, more than 70% of Mongolian pasture has been classified as degraded (UNDP, 2012). Since land privatization is not suitable for the traditional herding system, Mongolians are searching for solutions for pasture degradation by attempting to define the optimum-stocking rate for sustainable pasture use. The objectives of this study are to assess the Holistic Management (HM) application at family level decision-making and compare soil and vegetation quality at high and low stocking rate pastures. Application of HM allows us to integrate both traditional and scientific knowledge of pasture to help improve the pasture management decision-making by effectively addressing the pasture degradation within its whole socio-economic and ecological scenario. This project included learning about one family's decision-making process to document it as a pre-HM application, conducting HM workshops with the family, documenting their new decision-making processes, and with the study team and participant family to build the Resource Base Profile (RBP). After 6 months we compared the major changes and implementations of HM application, revised the RBP, and compared the two RBPs to assess changes. We sampled soil and vegetation at the herder's pastures of high and low stocking rate at the peak of growing season (July). We then compared those characteristics with the soil and vegetation quality that they prefer at their pastures. The two pastures differed significantly for both soil and vegetation parameters depending on the slope and aspect of the sampling point. In conclusion, for the study families, higher stocking rate has negative effects on pasture quality and it is contributing to pasture degradation in Mongolia. Herders using HM decision-making process and learning to assess soil and vegetation quality on their pastures are changing their pasture management decisions more sustainably.Item Watershed restoration limitations at the abandoned reclaimed Alta Mine, Jefferson County, MT(Montana State University - Bozeman, College of Agriculture, 2008) Labbe, Richard James; Chairperson, Graduate Committee: Clayton B. Marlow; Timothy R. McDermott (co-chair)Abandoned hardrock metal mines can have an antagonistic effect on soil productivity, vegetation, and water quality. Specifically, abandoned mines that actively generate acidity in soil are phytotoxic due to low pH and increased bioavailability of heavy metals. Arsenic concentrations in mine soils are often elevated, but may not be as mobile as heavy metals at low pH. Acid mine drainage migration from abandoned mines is problematic because it leads to water quality impairments that limit water use for certain activities (i.e. stock watering and irrigation). In this work, a previously reclaimed abandoned lead and silver mine (Alta Mine Jefferson County, MT) was characterized for its persistent impacts on soil, vegetation, and water quality. A progressive monitoring effort linked offsite water quality impacts to deep underground mine workings, shallow ground water, and metalliferous soils found at the Alta mine. Vegetative cover was measured in 16 transects in conjunction with 30 soil pits excavated on the reclaimed site. By regression and analysis of variance, sparse vegetative cover was significantly (p<0.1) linked to pH and acid generation potential. To overcome acidic soil conditions, lime and compost amendments were tested on site. The amendments significantly (p<0.1) neutralized soil acidity; however, a corresponding increase in vegetative cover was not observed. Erosion of the bare unstable slopes caused greater than anticipated seed bank loss that precluded vegetation establishment. The successful establishment of a dense vegetative cover on the abandoned mine could prevent erosion and water quality impacts due to sedimentation. Vegetation may also have minor impacts on landscape sources of arsenic and heavy metals that were identified in the study; but the most significant source of water quality impairment, deep underground mine workings, will persist under any land treatment.Item An economic analysis of variable rate nitrogen management on dryland spring wheat in Northern Montana(Montana State University - Bozeman, College of Agriculture, 2010) Whitmus, Jeffrey Donald; Chairperson, Graduate Committee: Richard E. Engel.The objective of this study was to compare hard red spring wheat (Triticum aestivum L.) grain yield (agronomic returns) and grain value (economic returns) of variable rate and uniform nitrogen (N) management using a data set obtained from eight on-farm experiments conducted over an eleven year period (1994-2004). Field experiments were established near Simpson, Malta, Havre, and Highwood, Montana using a strip trial design where N rates were varied in replicated strips along the length of each field. A digital elevation model was created for each field site using survey quality global positioning system data. Digital elevation models were segregated into four landscape classes or management zones (Upper Slopes, Middle North Facing Slopes, Middle South Facing Slopes, and Lower Slopes) using global information system software. Geo-referenced grid soil samples were collected at each field site location to determine background soil N levels. Geo-referenced yield and protein samples were collected at all field sites using a production sized combine equipped with yield monitor. The economic analysis consisted of partial budget analysis where only the changes in costs and revenues between variable rate and uniform N management were considered as part of net returns. In addition, spatial least squares (SLS) analysis was used as the basis for establishing whether wheat yields from variable rate N management were significantly greater than those from uniform N management. The SLS analysis failed to detect a significant difference in grain yield between variable rate and uniform N management. Variable N management used more fertilizer N and was less profitable than uniform N management in seven of the eight cases. Revenues from variable N management were insufficient to offset associated costs for needed information, hardware, and software. However, if Environmental Quality Incentive Program payments of $34.57 were considered as part of net income then variable rate N management was more profitable in all cases. Little evidence existed in this study that variable rate N management improves agronomic returns and profits, or reduces N use, especially in water limited conditions found in northern Montana.