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Item The role of land use change and land management in the global carbon cycle: simulation as a test of process understanding(Montana State University - Bozeman, College of Letters & Science, 2019) Calle, Leonardo; Chairperson, Graduate Committee: David Roberts and Benjamin Poulter (co-chair); Josep G. Canadell, Prabir Patra, Philippe Ciais, Kazuhito Ichii, Hanqin Tian, Masayuki Kondo, Shilong Piao, Almut Arneth, Anna B. Harper, Akihiko Ito, Etsushi Kato, Charlie Koven, Stephen Sitch, Benjamin D. Stocker, Nicolas Vivoy, Andy Wiltshire, Sonke Zaehle and Benjamin Poulter were co-authors of the article, 'Regional carbon fluxes from land use and land cover change in Asia, 1980-2009' in the journal 'Environmental research letters' which is contained within this dissertation.; Prabir Patra and Benjamin Poulter were co-authors of the article, 'A segmentation algorithm for characterizing rise and fall segments in seasonal cycles: an application to XCO 2 to estimate benchmarks and assess model bias' in the journal 'Atmospheric measurement techniques discussions' which is contained within this dissertation.Humans have left their mark on Earth's ecosystems for centuries. Since 1900, the human population has grown more than 400%. Land conversion and land management have helped meet an ever-increasing demand for natural resources. Forests have been cleared for agriculture, grasslands have been used for grazing by farmed animals, and extensive logging activity has provided fuelwood for energy and raw materials for building. But a long history of land management has also led to a change in forest production, leaving century-old legacies of human activity on Earth's ecosystems. As land is deforested, wood can be used for building or other products. Unused biomass can be burned for fuel or naturally broken down by microbes into soils, ultimately being converted to carbon dioxide. This phase conversion of carbon, from solid to gas, is a natural process but humans have sped up this process, leading to more carbon dioxide in the atmosphere than would otherwise occur naturally. Increasing levels of carbon dioxide in the atmosphere is a direct cause of increasing global temperatures and changes to regional climates. For these reasons, the focus of research in this Dissertation has been to track each and every process during land use change and land management, to provide a better accounting of where and how much carbon gets transferred from solid to gas during land use activities, and to identify any alteration to the productivity of ecosystems long after timber harvest has removed wood for products or agricultural lands have been abandoned and the forest allowed to regrow. The research papers in Chapter Two and Three have been published in peer-reviewed scientific journals, and Chapter Four is prepared for submission for publication. Each chapter focuses on a very specific problem, but the thread connecting all these works is carbon -- How much carbon is transferred to a gas when natural lands are modified and resources extracted to meet human demand? Does deforestation leave a unique and long-lasting signal in the atmosphere? Land management creates more young, fast-growing forests, but can models represent forests of different ages at global scales?Item Biophysical gradients and performance of whitebark pine plantings in the Greater Yellowstone Ecosystem(Montana State University - Bozeman, College of Letters & Science, 2019) Laufenberg, David Anton; Chairperson, Graduate Committee: Andrew J. HansenThe efficacy of planting efforts for species of conservation interest is important for ecosystem managers. Planting efforts represent an opportunity to conserve and manage species during a population crisis. Although federal agencies have been planting whitebark pine (WBP) in the Greater Yellowstone Ecosystem (GYE) for three decades, these efforts have been met with varying success. In this study, we use a combination of field sampling and remote sensing approaches in order to investigate local biophysical gradients as explanatory variables for WBP performance in GYE planting units. Present-day field sampling affords an opportunity to evaluate WBP performance relative to earlier planting and monitoring records. We used remotely-sensed temperature and precipitation alongside field measurements of elevation, aspect, slope, shading, and soils to utilize an adapted Thornthwaite-type water balance model to explain individual growth rates and site density change ratios (essentially survival and natural recruitment). We found that planting sites varied greatly in their biophysical characteristics and WBP performance. Five of twenty-nine sites had higher present-day density than at date of planting, therefore indicating some amount of natural regeneration occurring within those sites since time of planting. These sites were often higher in elevation, not south or southwest facing, and had soils that could hold moisture later in the season and for longer periods following precipitation events. Sites that experienced reductions in the density of WBP were often lower in elevation, with poorer soils, and facing south or southwest. They therefore experience greater potential evapotranspiration, and also greater water deficit when water demands are not being met. Notably, our two response variables, individual growth rate and site density change ratio represent short and long-term performance variables respectively. Although our results suggest that individual growth rates are likely more often limited by energy than water demands, the site density change ratio associated with this late to mature, long-lived species is likely a better benchmark for success. If they make it to maturity, trees planted this season will not begin to produce cones until the end of this century or the beginning of the next. Therefore, they must overcome forecasted periods of greater water stress in the coming decades and centuries. We strongly recommend planting efforts that seek to reduce the effects of increased drought stress by planting at sites with soils of greater water holding capacities (non-rhyolitic), planting on northerly and easterly aspects, and utilizing microsites particularly when planting at sites with potentially higher water stress. We also detected a negative relationship between the density of local competitors and WBP performance, but only at higher densities. Ecosystem managers will continue to plant WBP in the GYE for years to come, and this research helps to inform and identify high quality habitat during a period of changing climate and high GYE WBP mortality rates.Item Ecosystem management in the Greater Yellowstone Ecosystem : a coupling of human and natural systems(Montana State University - Bozeman, College of Letters & Science, 2003) Stanionis, Crystal Carleen; Chairperson, Graduate Committee: Richard AspinallThe Greater Yellowstone. Ecosystem (GYE) is one of the last, relatively intact temperate-zone ecosystems in the world. It is often invoked as a region that is ideal for the application of ecosystem management, yet no single plan or initiative currently exists for the area as a whole. Ecosystem management is seen as an alternative to traditional natural resource policies--those that been carried out within the confines of administrative units and have managed for a single species or a certain natural resource use. Ecosystem management differs from these policies in that it is holistic in its approach: it strives to manage whole ecosystems, which can cross numerous administrative boundaries, with the goal of achieving environmental sustainability. While there is an established body of literature that reviews the Greater Yellowstone Ecosystem in context of ecosystem management, no studies have explicitly explored the connections between stakeholder recognition of the Greater Yellowstone Ecosystem and ecosystem management. Thus, the two objectives of this study are to 1.) investigate the extent to which the GYE concept is recognized by various GYE stakeholders, and 2.) critically examine this recognition in terms of the prevalence of the ecological and human themes of ecosystem management. The research uses the information contained within management and land use planning documents from a variety of sources and administrations within the GYE. Additionally, a questionnaire survey of residents of Bozeman and Red Lodge, Montana and Jackson, Wyoming is used to assess current knowledge of, and attitudes towards, the GYE and ecosystem management. The results indicate that many GYE stakeholders recognize the Greater Yellowstone ecosystem concept, and they do so in a variety of ways that represent both the ecological and the human themes of ecosystem management. The geographic concept of 'place' facilitates interpretation of these results and aids in developing a perspective of the GYE as a coupled human-environment system. This research extends the current definitions of ecosystem management that are largely ecological, to more fully include human systems.Item A comparison of techniques for establishing Nebraska sedge and hardstem bulrush(Montana State University - Bozeman, College of Agriculture, 1998) Klausmann, Jeffrey M.Item Identifying linkages between aquatic habitat, geomorphology, and land use in Sourdough Creek Watershed(Montana State University - Bozeman, College of Agriculture, 2004) McIlroy, Susan Kay; Chairperson, Graduate Committee: Cliff Montagne.Aquatic systems reflect the geomorphological and land use processes that shape them. System function, structure, and composition are driven by both autogenous and exogenous processes at small- and large-scales. Impacts often act synergistically, increasing the complexity and magnitude of their effects on aquatic systems. To assess these impacts, watershed scale studies are becoming more common, and an integration of research and management is beginning to emerge. Diverse user groups and differing agendas complicate watershed management and restoration, making a collaborative decision-making process imperative. Objectives of this study were to identify linkages between aquatic habitat, geomorphology, and land use in Sourdough Creek Watershed, explore potential land use impacts in the Lower Watershed, and identify a sustainable management plan for the watershed. Specific questions involved identifying potential westslope cutthroat trout reintroduction areas in the Upper Watershed and exploring statistical correlations between six land classes and the response variables of large woody debris and pool length. This study found suitable reintroduction areas as well as identified linkages between predictor variables and LWD and pool length across land classes. Although others have assessed aquatic habitat on a large-scale as well as identified potential management paradigms, this study integrates the two in order to provide a useful document for stakeholders and managers of Sourdough Creek Watershed.Item Measuring ecosystem integrity in agroecosystems and rural communities(Montana State University - Bozeman, College of Agriculture, 1997) Knox, David Ernest; Conservation Reserve Program (U.S.)Item The effects of prescribed fire on riparian groundwater(Montana State University - Bozeman, College of Agriculture, 2007) Tucker, Ronald A., Jr.; Chairperson, Graduate Committee: Clayton B. Marlow.The hypothesis of this study is that the use of prescribed fire to reduce trees and tree canopy, on a watershed scale, will decrease depth to riparian groundwater, increase riparian plant species diversity, and increase riparian biomass production. To test these hypotheses two watersheds, primarily managed for cattle grazing, located in Fergus (Dry Armells watershed) and Jefferson (Little Whitetail watershed) Counties, Montana, were chosen. Both watersheds were densely dominated with coniferous tree species. Average preburn tree density was 1,276 trees/ha and 350 trees/ha for both the Dry Armells and Little Whitetail sites respectively. Ten riparian drainages were selected for treatment and analysis within the two watersheds. Six of these drainages were burned and four were used as unburned comparisons. Prescribed fires took place in the spring of 2001 at Dry Armells and in the fall of 2005 and spring of 2006 at Little Whitetail. At Dry Armells 18 to 20% of the watershed area was burned. At the Little Whitetail site only 3 to 15% of the watershed area was burned.Item Composition and modeling of riparian vegetation in the West Fork of the Gallatin River watershed(Montana State University - Bozeman, College of Agriculture, 2007) Shoutis, Levia Nima; Chairperson, Graduate Committee: Duncan T. Patten.Riparian areas contribute to the health of watersheds through their influence on hydrologic, biogeochemical, physical, and ecological processes. Limited research has focused on riparian systems of small mountain watersheds in the western U.S., which are increasingly under pressure from development activities. Watershed managers would benefit from an increased understanding of environment-riparian relationships in mountainous watersheds, for the purpose of assessing habitat and potential available nutrient buffering. This study assessed vegetation-environment relationships using digitally-derived terrain variables and wetland indicator scores, and used these relationships to assess the composition and model the cross-valley extent of riparian vegetation within the West Fork of the Gallatin River watershed in southwest Montana. Digital terrain analysis was used to extract the following terrain predictors: elevation above and distance from streams, plot gradient, valley width, and a topographic wetness index, which integrates the upslope area that contributes flow to a plot, and the plot gradient, thus serving as a measure of site wetness. Species abundance was used to assign weighted plot wetland indicator scores in order to focus on cross-valley gradients, with plots below a threshold score (mesic plots) designated as riparian plots.Item Characterization of soil/vegtation on flood irrigated hayfields in Grand Teton National Park, Wyoming : a predictive evaluation tool for agricultural wetlands(Montana State University - Bozeman, College of Agriculture, 2009) Summerford, Sarah Elizabeth; Chairperson, Graduate Committee: Clayton B. Marlow.The Elk Ranch hayfield in Grand Teton National Park (GTNP) has been historically flood-irrigated since the early 20th Century. The park service is now considering closing irrigation to restore native plant communities and enhance Spread Creek fisheries and will need information on the extent of irrigation-created wetlands and how irrigation cessation would change the vegetative component of the ranch. The main objective of this study was to assess the relation between soil and vegetation characteristics of wetland community types at the ranch and to determine if any of the relationships could be used to differentiate between naturally occurring and irrigation created wetlands. Vegetation data were collected from transects centered on a soil pit at 28 randomly located sample points throughout the hayfield. Twenty-six of the 28 sample plots were classified as wetland based on criteria listed by the US Fish and Wildlife Service. Bray-Curtis dissimilarity and nonmetric multi-dimensional scaling were used to analyze percent foliar cover, wetland index value (WIV), soil texture, percent organic matter, redox contrast and abundance, and depth to groundwater and soil saturation for each of the sampled points. The WIV and redox contrast had the greatest dissimilarity (D²), 0.90, and 0.71 respectively across the hayfield. The other measured characteristics had D² values ranging from 0.23 to 0.49 and were strongly correlated with the WIV and redox contrast measures. However, inclusion of these measures contributed little to the differences already identified. Categorical organization of WIV and redox measures indicated that naturally occurring wetlands could be differentiated from wetlands created by flood irrigation in former upland vegetation communities. Combining wetland index value and soil redox contrast suggests park managers could identify wetland community types likely to remain or transition following cessation of flood irrigation at the Elk Ranch. Additional testing at other GTNP sites will be necessary to test the broad application of this approach and refine the assessment categories.