Theses and Dissertations at Montana State University (MSU)
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Item Forecasting vertebrate species habitat suitability and ecoregion types under future climate change scenarios using Species Distribution Modeling (SDM)(Montana State University - Bozeman, College of Letters & Science, 2023) Veneros Guevara, Jaris Emmanuel; Chairperson, Graduate Committee: Andrew J. Hansen; This is a manuscript style paper that includes co-authored chapters.Peru, Ecuador, and Colombia have identified a total of 23 threatened species, including mammals, birds, and plants, which are also a part of their reports for SDG 15. These countries are keen to monitor the risk of extinction of these species and ensure their protection. As part of the Life on Land Project, we aim to assist these countries in approximating the IUCN Red List index using species occurrence data, climatic data, and variables such as Human Footprint (HFP) in different climate change scenario. To achieve this, we conducted a general review of climate drivers and climate change for the three countries and explored climate data to estimate the variation of temperature (°C) and annual precipitation (mm) change under current climate conditions and in RCPs-2050 climate change scenarios (2.6, 4.5, and 8.5). Our results indicated that the average annual temperature for 2050, using a baseline of 1970-2000, is expected to increase by over 1 °C in some areas and over 4 °C in others. For annual precipitation, an increase is also predicted, although few global circulation models show a reduction. We also conducted a median comparison to see the differences between the baseline and the RCPs in 2050, indicating that the medians are different. Density plots were used to illustrate the shift to the right for the temperature case, confirming the anticipated temperature increase by 2050 in the three RCPs. Finally, we used the R package (SDM) to estimate habitat suitability probability for the spectacled bear and the paramo ecoregion. Our findings indicated that climate change impacts their areas with high probability of occurrence to a great extent, and their habitats are also affected by HFP. These methods for exploring climate data and assessing habitat suitability are replicable and can be used with other environmental variables.Item Using remote sensing indices to analyze the influence of bare ground in dust source areas to total dust-on-snow load in the san juan mountains, colorado(Montana State University, 2021) Bilbrey, Christopher Edward; Chairperson, Graduate Committee: Scott PowellThe movement of dust across the western United States (US) has increased exponentially over the last 20 to 30 years driving a positive feedback regime altering the timing and magnitude of snowmelt. Dust radiative forcing of snowmelt can potentially exceed present day and likely future greenhouse gas forcing by two orders of magnitude. The semiarid landscape of the Colorado Plateau is one of the largest sources of dust in the western US. MODIS satellite imagery has been used to identify frequent, large-scale dust plumes that originate in the dust source area of northeastern Arizona, US and deposit that dust in the San Juan Mountains, Colorado. My study attempted to distinguish a "tele-link" between vegetation vigor in the dust source area and end of season total dust load in the San Juan Mountains from October 1 to June 30 for the years 2016 to 2021. The Normalized Difference Vegetation Index (NDVI) is a principal index tool used in multitemporal vegetation monitoring, and is commonly used as a direct indicator of vegetation health and growth. NDVI allows us to delineate the distribution of vegetation and bare soil based on the characteristic reflectance patterns of green vegetation. My study compared monthly NDVI mean values acquired by MODIS and Sentinel-2 to evaluate each satellites efficacy at modeling vegetation cover. Results suggest the association between vegetation vigor, bare soil, and total dust load is more complex and a number of factors could influence the inter-annual variability of dust-deposition. Statistical analysis employing ANOVA and multiple means comparison effectively identified pairwise groups who's monthly NDVI mean values were significantly different from others and 95% confidence intervals of the true expected difference, but failed to distinguish a "tele-link" between change in vegetation vigor and end of season total dust load. Finer-spatial resolution imagery captured more local variability in change in vegetation vigor over time and expanded the significant NDVI sampling window from 30 to 60 days. Projected climate change will likely increase aridity in the southwestern US, reduce the amount of vegetation cover, increase the amount of bare soil and enhance dust emission throughout the years.Item Improving restoration of breeding sites to increase recruitment of anaxyrus boreas in western montana(Montana State University, 2021) Johns, Nathanael David; Chairperson, Graduate Committee: Scott PowellThe Montana native western toads (Anaxyrus boreas) have, like most amphibians, been declining in recent years. Although it is endangered and at high risk of extirpation in many states, there are still several healthy breeding populations in Montana. Montana can increase recruitment of this increasingly rare anuran species through habitat restoration. However, using habitat restoration to addressing the decline of this species is not well researched. Here, I evaluate potential restoration methods that could increase recruitment. I provide an overview of the habitat requirements and preferences of A. boreas as well as effective restoration methods for this and other anuran species. To increase recruitment, restoration efforts should include construction of permanent ponds with low turbidity and extensive shallows that gradually increase to a maximum depth of 40 cm. Trees should be removed along the pond perimeter if they shade the water. Active management measures such as sediment removal in ponds, strict regulation of livestock grazing, periodically prescribed burns, and removal of invasive species such as the American bullfrog (Lithobates catesbeianus) should also be implemented. Farther from the breeding site, native deciduous shrubs should be planted, if they are not otherwise present. For existing breeding sites, the area within a 3-km radius should be protected from development and clearcuts. Introduction of beaver (Castor canadensis) to their historical range will also have a significant beneficial impact on the restoration of A. boreas. The locations of these efforts should also be carefully chosen to take into account the continuing effects of climate change. Taking these actions now, based on the data that are available, will help increase recruitment and improve the chances of this species recovering.Item 'Hypertemporal' remote sensing of plant function: a comparison of phenocam and geostationary operational environmental satellite NDVI data products(Montana State University - Bozeman, College of Agriculture, 2019) Douglas, James Thomas; Chairperson, Graduate Committee: Paul C. StoyOngoing climate warming is changing the seasonality of plant canopy function, but common approaches to explore these changes via polar-orbiting satellites often miss rapid canopy transitions due to infrequent observations. I explored the ability of satellites designed for studying weather systems, namely The Geostationary Operational Environmental Satellite (GOES), to track plant canopy status on time scales of minutes. With new capabilities to remotely sense in the infrared, the GOES weather satellites now have the capability to detect photosynthetic activity. Satellite observations of the normalized difference vegetation index (NDVI) are compared against near-surface phenological camera ("PhenoCam") observations from the National Ecological Observation Network (NEON, Inc.) at six sites every 15 minutes for one week in April 2019. Diurnal trends across both observation platforms showed the expected diurnal parabolic structure in NDVI with critical differences in NDVI magnitude between PhenoCams and GOES observations. One tailed T-test results show that there is variability between methods when measuring NDVI, with P-values less than 0.05 in all cases. This was anticipated due to correction factors needed for PhenoCam NDVI observations. However, additional variability can be attributed to other areas such as cloud cover, plant type, and heterogeneity. My proof-of-concept study demonstrates that raw NDVI data from both methods are often comparable, which lends credit to the notion that NDVI can be accurately observed from space at high (up to five minute) temporal resolution. With current research underway on the topics of atmospheric corrections and further surface validation, GOES has the potential to observe land surface attributes at up to 5-minute intervals across entire hemispheres for identifying phenology, disturbance and other vegetation dynamics in real time. With two hypertemporal methods at different spatial scales recently introduced, the research is primed to move towards a real time understanding of plant canopy function across the United States.Item Evaluating growth-defense trade-offs in ponderosa pine (Pinus ponderosa) in response to stimulated bark beetle attack(Montana State University - Bozeman, College of Agriculture, 2019) Hull-Jones, Jessica Wrae; Chairperson, Graduate Committee: Amy TrowbridgeThe mountain pine beetle (MPB; Dentroctonus ponderosae, Hopkins, Coleoptera: Curculionidae: Scolytinae) and its associated blue stain fungi are considered to be among the greatest natural threat to conifer ecosystems worldwide. In response to a rapidly changing climate, namely more frequent and hotter droughts, bark beetles benefit through a combination of higher reproductive capacity and greater availability of weakened and stressed host trees. Conifers have potent constitutive and induced chemical defenses to resist the bark beetle-fungi complex, but investment in these carbon-based defenses may be constrained by trade-offs associated with a tree's inherent growth rate. Although there are trade-offs that exist among all processes, it is unclear whether those particular growth-defense trade-offs are measurable and can be compared between individuals within various populations. Here we assess the concentration and composition of constitutive and induced terpene chemical defenses as a function of intraspecific variation in growth rates (slow-versus fast-growing mature ponderosa pines). We examine these relationships in the context of classical plant defense theories as well as the current state of the field. By determining the variation in chemical responses to stimulated bark beetle attack we can further our understanding of potential resistance trade-offs that might exist in stands that are being selectively bred for fast growth.Item A critical assessment of technologies for the study of organic matter in glaciers and ice sheets(Montana State University - Bozeman, College of Agriculture, 2019) Willis, Madelyne Claire; Chairperson, Graduate Committee: Christine ForemanPolar and temperate glaciers harbor active microbial communities and a substantial storage of organic carbon. These frozen ecosystems are especially sensitive to the effects of climate change and are expected to release roughly 15 teragrams of carbon by 2050. This creates a sense of urgency for further experimentation to increase our understanding of glacier ecosystem function and the impact glacier habitats have on local and global biogeochemical cycles. Due to the complex nature of organic matter, there is no single method which is suitable for every study. Technological advancements have improved methods for determining the quantity and quality of organic matter and emerging new technologies are providing faster and less-costly ways to overcome the challenges of working in these harsh environments. Consequently, a synthesis of peer-reviewed literature was conducted to summarize the current state of microbial ecology of glaciers and ice sheets, and to explore the techniques and new tools which are being developed to aid in the study of these rapidly disappearing ecosystems. The culmination of this work is an introduction and guide for analysts interested in examining the source, transformation history, and fate of organic matter in glacial systems. It was found that there is not one single technique superior to another, rather the appropriate technique is dependent on the questions being addressed and the resources available.Item Irrigation ditches as novel intermittent stream networks that provide energetic subsidies to terrestrial ecosystems via aquatic insect emergence(Montana State University - Bozeman, College of Letters & Science, 2024) Heili, Nathaniel Maxwell; Chairperson, Graduate Committee: Wyatt F. CrossNon-perennial streams dominate fluvial networks, comprising over half of lotic ecosystems globally. Although little attention has been paid to these systems relative to those that are perennial, perhaps even less is known about the ecology of artificial intermittent streams. In irrigated river valleys, ditches comprise a substantial proportion of surface water networks, but little is known about their relative contributions to lotic habitat, freshwater biodiversity, and ecosystem processes. Because ditches are abundant and permeate arid floodplains, they create new opportunities for cross-ecosystem subsidies through emergence of adult aquatic insects. Here, we mapped the extent of an irrigation ditch network relative to natural surface waters in the Gallatin River Valley, Montana, USA. We also quantified the magnitude, composition, and phenology of aquatic insect emergence in ditches throughout a full irrigation season and compare emergence to nearby natural streams in the valley. We found that non-perennial streams, both natural and artificial, dominated the surface-water network, representing over 70% of total length. Irrigation ditches also constituted 37% and 23% of total length and surface area of all waterbodies in the valley, respectively. Insect emergence production from ditches averaged 32.0 mg m -2 d -1 and exceeded fluxes from nearby natural streams, which contained more classically sensitive taxa (i.e., Ephemeroptera, Trichoptera, and Plecoptera). Ditches varied in water temperature, substrate size, and flow permanence, leading to distinct emergence timing, species composition, and magnitudes of biomass flux. One of the study ditches dried early because of more 'junior' water rights, but this ditch provided the largest emergence subsidy, including a pulse of dipteran emergence at the onset of flow cessation. Annual production from intermittent ditches was ~6 g m -2 y -1 and was comparable to estimates from natural perennial streams. Although our study focused on one river valley of the western US, results suggest that these ecosystems contribute broadly to lotic habitat, heterogeneity, and cross-ecosystem subsidies via aquatic insect emergence. Given increasing demand for water and changes to flow regimes and water management driven by climate change, additional study is needed on these novel and underappreciated artificial ecosystems.Item Fertility and reproductive health decisions connected to climate change and adaptation in Greenland(Montana State University - Bozeman, The Graduate School, 2024) Peterson, Malory Kaye; Chairperson, Graduate Committee: Elizabeth Rink; This is a manuscript style paper that includes co-authored chapters.The capacity for Kalaallit, the Inuit people of Greenland, to adapt to the effects of climate change will depend on sociodemographic change, population distribution, and existing health inequities in the country. Reproduction in Greenland is influenced by connection to place and access to natural resources, factors that will vary with climate adaptation. Given existing fertility and reproductive health disparities among Kalaallit women, there is a compelling reason to explore how climate change effects and adaptation might influence fertility decisions and population dynamics in Greenland. Rooted in the principles of community based participatory research, this exploratory and comparative study investigated the social, environmental, and economic resources that affect fertility decisions for Kalaallit in Greenland. The research presented contextualizes drivers of fertility decisions within Greenland's climate adaptation policy options and presents strategies to guide health studies in Greenland with principles of community based participatory research. Interviews were conducted with 35 reproductive-aged (18-49 years) men and women and 26 interviews with policymakers and key stakeholders in two communities about climate adaptation, natural resources, economic development, and fertility and reproductive health. Interviews were analyzed using constructivist grounded theory in collaboration with a Kalaallit community research partner. Results indicate that improving community capacity to address existing housing, education, and economic inequities is critical to supporting fertility and reproductive health, irrespective of climate change impacts. Participants observed climate change effects and expressed positive attitudes about Kalaallit ability to adapt and capitalize on benefits of climate change. Evidence from this study indicates that addressing development disparities in Greenland may immediately support fertility and reproductive health for Kalaallit people and facilitate equitable climate adaptation.Item The effects of guiding climate change education through a social justice lens(Montana State University - Bozeman, College of Letters & Science, 2023) Arnold, John Francis; Chairperson, Graduate Committee: C. John GravesClimate change is one of the largest environmental and justice issues facing our world. Many young people are listening to the science and taking action, but many more are not. This project addressed climate change through exploring consequences on society, addressing public health, and impacts on societal infrastructure and stability. The social inequality of climate impacts was highlighted throughout to better engage students. Baseline, survey data was collected before we addressed climate change. After learning about public health concerns, students took the survey again and completed a short reflection. Students finished the study, after learning about impacts on societal infrastructure by taking a third survey, completing a second reflection, and with an interview. Results varied due to inconsistent participation throughout the study. Many students demonstrated an increase in understanding of climate change, but evidence to demonstrate their depth of understanding examples of people most disproportionately affected by climate change was inconsistent. Finally, students underreported eco-anxiety in survey results compared to interview results.Item An interpreter's guide to filmmaking(Montana State University - Bozeman, College of Arts & Architecture, 2022) Andrus, Olivia Fay; Chairperson, Graduate Committee: Dennis AigPolitically divisive topics like climate change are notoriously difficult to effectively communicate to the public. Using a different communication approach called interpretation within the filmmaking process, we can bridge the gap current climate change films have today with their audience. Interpretation means "a mission-based communication process that forges emotional and intellectual connections between the interests of the audience and the meanings inherent in the resource," according to the National Association of Interpretation (What is interpretation?). In this paper I will analyze the history behind interpretation and the methodology in implementing this communication style within films. Through the works of various filmmakers such as, My Octopus Teacher (2020), Ice on Fire (2019), and Ocean Souls (2020), my own experience creating an interpretive short film, The Dolphin Dilemma, this paper will discuss how specific interpretive communication methods can take politically divisive subjects, like climate change and more effectively communicate science within documentaries.