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  • Thumbnail for Relict tallgrass prairie of the Upper Black Squirrel Creek drainage, El Paso County, Colorado : change since the 1940's
    Relict tallgrass prairie of the Upper Black Squirrel Creek drainage, El Paso County, Colorado : change since the 1940's by Tsocanos, Sebastian A. E.

    In the mid 1940s remnant tallgrass prairie near Colorado Springs was recognized in vegetation studies on the plains. Tallgrass prairie is unusual in the arid Great Plains, and is of significant conservation value, particularly given the past and present pressures of urban expansion, intense grazing, and water development. Our study examined the question of whether this community type still exists in the region, if the extent of the community type has changed since then, and whether the species composition has changed. We found that while true tallgrass prairie vegetation is no longer dominant at many of the sites used in the original studies, patches of true tallgrass prairie still occur in the area. The extent of tallgrass prairie in the vicinity has clearly declined over the past 70 years. The vegetation of remaining patches is composed of very similar species to those originally documented. We found that the dominant vegetation is still characteristic of true tallgrass prairie. Among the important grasses were prairie dropseed, indian grass, little bluestem), and big bluestem. Important widespread forbs indicative of true tallgrass prairie included american licorice (Glycyrrhiza lepidota), stiff goldenrod (Oligoneuron rigidum), white heath aster (Symphyotrichum ericoides), and purple prairie clover (Dalea purpurea) among many others. We determined that overall precipitation and temperature in the locality has not changed dramatically since the 1940’s. The alluvial aquifer across much of the area is evidently little changed, but hydrology on a site-by-site basis is poorly understood. While the continued existence of some true tallgrass prairie communities here is reassuring, their diminished extent is cause for concern, especially given increasing pressure from urban expansion, livestock grazing, invasive species, and water development. The uncertain status of future temperature and precipitation, as well as the maintenance of critical surface and subsurface hydrologic regimes is also of concern.

  • Thumbnail for Micrometeorology of a Diffuse Tree Line: How do airflow structures affect sensible heat flux divergence and temperature-controlled tree growth?
    Micrometeorology of a Diffuse Tree Line: How do airflow structures affect sensible heat flux divergence and temperature-controlled tree growth? by Sondermann, Dylan P

    Harsch (2009, 2011) determined that diffuse tree lines are advancing globally as a response to warmer growing season temperatures. However, few have studied the local micrometeorological processes that change local climatic conditions for trees. This thesis aims to understand local airflow patterns and heat distribution within a diffuse tree line on Pikes Peak (Teller County, CO). Previous research identified that the study site represents an advancing tree line that has transitioned from an abrupt to a diffuse structure within the last century (Kummel et al. 2009-present). The mountain location of the study site governs large-scale wind patterns as an anabatic-katabatic wind system. On a more local scale, surface interactions at the diffuse tree line alter daytime flows, resulting in the formation of a low level jet. This jet alters climatic conditions by creating three vertical sub-layers with different atmospheric properties. A preliminary heat budget analysis of the diffuse tree line confirms the findings of jet characteristics while also determining that the low level jet is capable of altering vertical heat distribution and depositing heat as flows move uphill. This heat deposition is likely connected to growth patterns studied by Marks (2014) and overall tree line dynamics (Elwood et al. 2012).

  • Thumbnail for Characterization of secondary organic aerosol formed from pyruvic acid photolysis
    Characterization of secondary organic aerosol formed from pyruvic acid photolysis by Severson, Rachel

    Pyruvic acid is ubiquitous in the atmosphere and currently used as a proxy for similar molecules in climate models. We produced secondary organic aerosol (SOA) from the aqueous photolysis of pyruvic acid, and aerosol yield and cloud condensation nuclei (CCN) activity was measured. Aqueous samples were atomized to obtain the volume of aerosol produced per volume of initial pyruvic acid (aerosol yield) and the hygroscopicity parameter (κ) was determined. At room temperature (21°C), unreacted pyruvic acid was atomized to yield ~ 4% aerosol with κ = 0.22. Significant formation of aerosol from unreacted volatile pyruvic acid implicates the potential involvement of self-oligomerization via hemiketal formation. After photolysis, a 0.1 M aqueous sample of pyruvic acid led to an increased aerosol yield of ~ 15%, and a decrease in κ to 0.13. This decrease in κ after photochemical aging is in contrast to conventional hypotheses regarding in-cloud SOA formation, which generally predict an increase in hygroscopicity. The potential roles of variable environmental conditions in SOA formation were also investigated. Pyruvic acid photolysis carried out at 15°C, pH 2 and 21°C, pH 7 gave a decrease in κ from 0.2 to 0.13, and from 0.22 to 0.12, respectively. At pH 7, photolysis resulted in a lesser increase in aerosol yield from ~ 6% to only 10%; aerosol yield increased in the 15°C condition from 5 to 18%. These results support the importance of further investigation of SOA formation and composition, and of the effects of fluctuating environmental conditions—these effects are not currently well understood, but are likely important on a global scale.

  • Thumbnail for Community Interactions between Two Monkeyflowers and their Pollinators in Mt. Rainier National Park: Mimulus guttatus and Mimulus tilingii
    Community Interactions between Two Monkeyflowers and their Pollinators in Mt. Rainier National Park: Mimulus guttatus and Mimulus tilingii by Sebastian, Laurel Taylor

    Community interactions form the foundation of ecosystems, but their complexity makes predicting species responses to new pressures a difficult challenge. For example, if climate change forces the upward range shift of one species in a system, closely interacting species will either suffer or excel under the new community compositions. This study explores the interactions between two closely related monkeyflowers (Mimulus tilingii var. caespitosus and Mimulus guttatus) and their shared pollinators in order to understand potential responses to future climate changes or species loss. We arranged plants in three community composition treatments (heterospecific, conspecific, and no neighbors) to understand how plant fitness and pollinator visitation are affected by neighboring plants. Specifically, does plant fitness decrease due to pollen limitation or heterospecific pollen deposition under any community treatment? Furthermore, how does environmental data illustrate the system’s response to climate variation at different temporal scales? In our experiment, M. tilingii produced fewer seeds under the conspecific community composition and pollinator exclusion treatments (both p<.001), likely due to intraspecific resource competition and pollen-limitation. Rather than impeding plant fitness, it appears heterospecific interactions may actually stabilize M. tilingii populations. Plants and pollinators also responded positively to higher temperatures and lower cloud cover, indicating sensitivity to climate. Thus, changes in plant or pollinator species abundances, or climate could severely impact the dynamics or viability of the system.

  • Thumbnail for Salmon in the Status Quo: Natural Resource Management Decisions &amp; Promoting System Resilience in the Columbia River Basin
    Salmon in the Status Quo: Natural Resource Management Decisions &amp; Promoting System Resilience in the Columbia River Basin by Criswell, Benjamin U

    If society accepts the status quo of salmon recovery and Federal Columbia River Power System operation in the Pacific Northwest, many populations of salmon will not survive into the 22nd century in sustainable, harvestable levels. Status quo management of the Columbia River–similar to past decades–gives priority to hydropower, irrigation, and navigation interests. It oversees earnest and well-funded salmon recovery efforts that amount to meager success. Its management structure is disjointed, juxtaposed with the interconnectedness of the Columbia River Basin’s ecology. Looking decades into the future, a timely combination of increased human population in the Pacific Northwest, a warmer climate, unfavorable ocean conditions, and an unaltered hydropower system will push salmon populations to minimal abundance, perhaps even to extinction. Yet it is entirely possible to design policies that would increase system resilience in the Columbia, and therefore decrease the likelihood of the grim fate mentioned above. These policies and management decisions must consider human resilience and ecological resilience alike, and should have a shared definition of success, with legal, regulatory, ecological, social, cultural, and economic dimensions.

  • Thumbnail for Water quality in Bali : a multiperspectival approach
    Water quality in Bali : a multiperspectival approach by Bellows, Zachary David

    Water pollution in Bali due to human waste and agricultural runoff is a serious concern. Social and cultural influences such as rigid social structures, tourism, and weak infrastructure contribute to water pollution on the island. In an attempt to quantify the extent of the pollution, nutrient concentrations and other relevant variables were measured at seven points along the Yeh Ho River seven times in June, 2013. Interviews were also conducted to provide social and cultural context. The results of the study indicate that nutrient concentrations increase significantly as the water travels downstream from 15 (± 1.9) to 40 (± 3.2) ppm nitrate-NO3 and from 0.16 (± 0.06) to 0.61 (± 0.06) ppm phosphorous-PO4. In addition, nutrient concentrations on June 18th were higher across all sampling sites than the measurements on other days by 9.0 (± 2.4) ppm nitrate-NO3 and by 0.53 (± 0.06) ppm phosphorous-PO4. Generally, the levels of N and P in the Yeh Ho River are significantly higher than the expected natural background levels of nutrients in rivers. These trends are likely attributable to significant, uncontrolled, anthropogenic inputs into the Yeh Ho River. The qualitative data corroborates this interpretation. Other explanations for this nutrient increase include changing uptake rate due to geomorphological changes of the river, or systemic error introduced by sampling downstream sites later. However, these factors are likely negligible relative to anthropogenic inputs.

  • Thumbnail for Wildfire severity effects on in-stream large wood in the Frank Church-River of No Return Wilderness, Idaho
    Wildfire severity effects on in-stream large wood in the Frank Church-River of No Return Wilderness, Idaho by Stauffer-Norris, Will A.

    Large wood (LW) provides habitat to aquatic organisms and can significantly alter stream geomorphology. Sources of LW to stream ecosystem originate in riparian forests and are influenced by wildfire regimes. To quantify the relationship between burn severities and in-stream LW, we surveyed 15 low order streams effected by varying wildfire burn severities in a near-pristine watershed of the Frank Church River of No-Return Wilderness in Central Idaho. In the field and using remotely sensed imagery, burn severity was divided into four categories: “unburned,” “low,” “moderate,” and “high”. We hypothesized that burn severity would be positively correlated with in-stream LW. Alternatively, in areas with the highest burn severities, LW might be limited due to combustion. To test this hypothesis we used principal components analysis that indicated fire severity, recruitable LW, and pre-fire vegetation are the most important predictors of in-stream LW in landscapes with a natural wildfire regime. In particular, high category severity burns had significantly more LW than the other categories. An increase in burn severity is also correlated with increased average piece size. The comparison of fire severity maps to field data found a significant correlation locally but no correlation with fire severity of upstream reaches. Few studies have compared the interaction of in-stream LW and fire severity in a near-pristine stream ecosystem. The results of this study improve our understanding of LW dynamics in Intermountain West watersheds with a natural wildfire regime, and could inform post-fire salvage logging management practices.

  • Thumbnail for Reconciling institutional levels of water governance and management for the Monterey Peninsula water supply
    Reconciling institutional levels of water governance and management for the Monterey Peninsula water supply by Hall, Andrew

    Water managers in the West are faced with multiple and compounding challenges from climate change, spatial-administrative complexity, legal uncertainty and increasing demand from population, industry and environment needs. This article thus assesses the current state of water management in California by specifically looking at the fragmentation of governance and management and the variable management schemes proposed to solve the problems. As current management has resulted in delays and failures, new political factions and economic and environmental burdens have added new stresses for water managers. My study area is the Central Coast of California specifically the geographic region of the Monterey Bay, with a specific focus on the Monterey Peninsula (MP), Carmel Bay and South Monterey Bay Region. The methodology consists of a qualitative examination of water governance and management responses in the region through interviews, analysis of documents and materials, and direct observations of practices. The results demonstrate that decentralized management in CA has led to multiple dimensions of jurisdictional fragmentation and legal uncertainty relevant to all water managers in the state. Furthermore, the paradigm shift that is taking place in water management towards a more integrative and adaptive framework is hampered by these barriers and has been slow to take effect. Thus, further research is necessary to monitor this shift and to document ways to overcome current legal and political-administrative barriers.

  • Thumbnail for The Cow in the Room: Regulating the Environmental Harms of Industrial Animal Agriculture
    The Cow in the Room: Regulating the Environmental Harms of Industrial Animal Agriculture by Palko, Gabriella

    Despite being the largest US methane emitter, the main source of water pollution, the driving force behind species extinction and habitat loss, and an intensive natural resource user, animal agriculture is scantily regulated and almost never considered as an option for combating climate change. This thesis seeks to provide a comprehensive analysis of the widespread environmental harms of the meat industry to demonstrate why it must be controlled. The historic 2015 Paris Agreement provides a framework for policy makers to address several ecological and climate threats, and regulating animal agriculture falls directly in line with the provisions put forth in the agreement. In order for the US to uphold their emissions reductions commitment and duties under the Paris agreement, industrial animal agriculture must be addressed. Current policies are examined as either hindrances or tools for controlling the detrimental impacts of the industry, followed by recommendations for policy vehicles and outlets to regulate the widespread degradation from industrial animal agriculture. If the earth is to avoid catastrophic climate change and ecological collapse, the cow in the room must be addressed.

  • Thumbnail for Establishing community gardens for long-term success
    Establishing community gardens for long-term success by Yemma, Melanie

    Urban agriculture has had a strong presence in American cities throughout history, whether from concerns of food security or desires for green spaces. In the past two decades, gardens have made a large comeback due to grassroots and community desire to build community and partake in the local food movement. Common literature has agreed on the benefits that gardens can provide for cities, but no study has found what it specifically takes to establish gardens successfully, in order for their benefits to consistently show for the long-term. This study determines what factors are necessary to establish community gardens with longevity in mind. Through extensive analysis of existing literature, this study finds that the three largest factors for establishing and maintaining community gardens are community interest, support for resources, and organized structure. This study then examines how these factors are specifically at play in Colorado Springs, as the city’s budding interest in gardening makes for an exemplary case study. For Colorado Springs, this study finds that while community interest and mechanisms for resource support are present when it comes to establishing gardens, in terms of longevity, a lack of consistent structure for supporting and maintaining community gardens could hinder the longevity of community gardens. It is proposed that more organization and structure for the gardens, especially in regards to leadership development, can promote the success of these gardens, as well as other gardens nation-wide, for the future by making gardens more self-sustaining.

  • Thumbnail for A historical relational analysis of vulnerability to the Waldo Canyon Fire
    A historical relational analysis of vulnerability to the Waldo Canyon Fire by Hayden, Mollie

    During the summer of 2012, images of hillside homes engulfed in flames played on repeat on news stations across the country. In the foothills of Pikes Peak, the Waldo Canyon Fire burned 18,247 acres, destroyed 347 homes, and killed two people between June 23 and July 10, 2012. Catastrophic fires such as the Waldo Canyon Fire are increasingly common throughout the west, especially in the wildland urban interface (WUI). These mega-fires are far from the natural disturbances that occur in many Western ecosystems. Instead, they are the product of a century of federal fire suppression compounded by changing climatic conditions. This scenario is complicated by increasing development in the WUI, where houses literally add fuel to the fire . This research assesses the specific conditions that contributed to the production of vulnerability to the Waldo Canyon Fire.

  • Thumbnail for The Vulnerability of California Amphibian Species to Climate Change
    The Vulnerability of California Amphibian Species to Climate Change by Ben-Zeev, Rayna

    Amphibians are declining on a global scale, faster than any other taxonomic group. Although I am still unsure of the causes of many local declines, I have evidence that on a larger scale temperature and precipitation changes caused by climate change directly relate to broader amphibian disappearances. I aim to use past temperature and precipitation trends and amphibian distributions in California to predict future amphibian distributions. I use the Biomod2 package in R, along with CMIP5 climate layers and emissions scenarios to correlate amphibian distributions to climate, and predict a range of future possibilities for amphibians under different carbon emission scenarios. I hope to identify which species are most in danger of extirpation to hopefully direct future management initiatives to these species.

  • Thumbnail for The Roots of Impasse: How Neoliberalism has Shaped Recovery Planning for Endangered Fish in the Columbia River Basin
    The Roots of Impasse: How Neoliberalism has Shaped Recovery Planning for Endangered Fish in the Columbia River Basin by Linse, Lea Michelle

    Management of the Columbia River has come to an impasse: after decades of litigation and controversy, there is a growing sense among stakeholders that there may be no good solution to the conflict between endangered salmon and the region’s expansive hydroelectric generation system. Dams and reservoirs pose severe challenges to the survival and migration of salmon and have been blamed for significant population declines over the past century. Addressing this issue, however, is complicated by the fact that river management strategies to benefit the fish often require operational changes that reduce the productivity of hydroelectric power generators, and thus they are strongly opposed by hydroelectric interests and dam operators. Still, the National Marine Fisheries Service, the agency charged with ensuring that other federal agencies’ actions (including actions of federal dam operators) do not jeopardize listed species, is constantly pressured by Native American tribes, environmental groups, and other stakeholders to implement just that sort of management plan. Caught between the two sides, the NMFS, instead of being decisive, has tended to avoid upsetting the status quo and has been often criticized for it. This report seeks to explain why the NMFS has been so reluctant to regulate the hydroelectric system. It shows that, despite the authority of the NMFS the Endangered Species Act, they must operate within the confines of what is politically feasible. Political feasibility is constrained in part by the legacy of a trend toward neoliberalism that gained influence in U.S. politics during the 1980s and 1990s. Specifically, neoliberal policies aimed at limiting federal involvement in economic activities and private land under the ESA have become impediments to federal action in the Columbia that would give endangered fish priority over development activities that threaten their survival. Two such policies are analyzed in this report, the “no surprises” policy, which was originally designed for private landowners but is now used between regulating and regulated agencies, and the “best available science” mandate for federal action under the ESA.

  • Thumbnail for The Effects of Growing Season Soil Temperature on Engelmann Spruce Seedling Establishment, Survival, and Growth in an Abrupt Treeline on Pikes Peak, Colorado
    The Effects of Growing Season Soil Temperature on Engelmann Spruce Seedling Establishment, Survival, and Growth in an Abrupt Treeline on Pikes Peak, Colorado by Cutler, Victoria

    Previous studies have found treeline dynamics to be related to macroclimatic factors (Harsch et al., 2009) and microclimatic factors such as local snowpack, wind, and air and soil temperature (Germino, Smith, and Resor, 2002; Harsch et al., 2011; Smith et al., 2003). Seedling health has been thought to indicate the future of treeline position (Germino et al., 2002; Smith et al., 2003; Harsch et al., 2011) and has appeared to be highly related to soil temperature (Grace, Berninger, and Nagy, 2002; Harsch et al., 2011; Smith et al., 2003; Körner et al., 2004; Malanson et al., 2011). This study examines the effects of soil temperature on seedling establishment, survival, and growth, and the degree to which soil temperature may influence seedling dynamics relative to other factors. Daytime and nighttime soil temperature, as well as seedling establishment, survival, and growth data, were collected in an abrupt treeline consisting entirely of Engelmann Spruce (Picea engelmannii) on Pikes Peak, Colorado (~3,550 m). The study site was split up into three different microsites with unique microclimates – the Lower Sheltered Zone, Upper Sheltered Zone, and Tundra – where the relationships between seedling dynamics and soil temperatures could be analyzed separately, and post hoc analyses were conducted to compare the broader zonal relationships. Seedling establishment within the Lower Sheltered Zone was generally greater than expected in the warmer areas and less than expected in the colder areas. Establishment in the Tundra, however, followed the opposite pattern. Survival was largely statistically unrelated to soil temperature, unless a certain threshold was surpassed within the Lower Sheltered Zone and Upper Sheltered Zone. Growth was statistically significantly related to daytime soil temperatures within the Lower Sheltered Zone by a second-degree polynomial, with an optimum at 7.87°C (R2 = .39, n = 16, p = 0.04), but statistically unrelated to soil temperatures within the other two zones. Post hoc zonal comparisons of seedling dynamics revealed relatively large statistically significant differences, which suggested that other microclimatic factors were influencing seedling dynamics more than soil temperatures.

  • Thumbnail for The Toxicity Identification Evaluation assay as a tool for Wastewater Management
    The Toxicity Identification Evaluation assay as a tool for Wastewater Management by Hanahan, Jonathan

    As terrestrial and marine ecosystems increasingly experience detrimental stress from pollution and contamination, contemporary waste management should consider wastewater as more than just trash to discard, but instead as a crucial resource to be developed. The Toxicity Identification Evaluation (TIE) is one of more comprehensive ecotoxicological methods which can evaluate and address toxic wastewater mitigation without knowledge of the specific toxic components. The aim of this study was to explore the effectiveness of TIE from a wastewater management standpoint by a) Testing the TIE method on a specific toxic aqueous effluent produced from a Danish offshore oil drilling operation, and b) assess its efficacy in the broader context of environmental management through a comparison of scientific literature on wastewater management. By applying TIE in conjunction with a MicrotoxTM equivalent toxicity test, this study found that an initial biological treatment followed by the application of activated carbon, is effective for addressing the toxic fractions of the oil produced wastewater. An analysis of the literature reveals that the strength of TIE compared to other more chemically specific techniques is in its broad application and ability to be applied to unfamiliar toxins and situations. Overall, the TIE is a critical tool to be considered and recommended for wastewater management as well as broader environmental management.

  • Thumbnail for WIND MOVEMENT AND SHELTERING CREATED BY AN ABRUPT TREELINE ON PIKES PEAK, COLORADO
    WIND MOVEMENT AND SHELTERING CREATED BY AN ABRUPT TREELINE ON PIKES PEAK, COLORADO by Dreyer, Kellen

    Alpine treelines are very unique ecotones which are visibly responding to climate change worldwide. As global climate change persists alpine treelines are expected to migrate into higher elevations. Not all alpine treelines however are uniform and the microclimates created at the surface have seen to be essential for seedling establishment. The particular microclimate along treeline will dictate how heat is distributed which will ultimately control tree survival. This study discusses how wind interacts with treelines when coming from different directions and where areas of sheltering are created. An area of interest was created along treeline on Pikes Peak in Colorado where wind speeds were measured along a transect moving from the forest up to the tundra above. As expected it was found that a large sheltered area of slow air was created when wind moves uphill over the forest. Downhill moving wind shrinks this sheltered area especially during periods of faster wind. Wind parallel to treeline was found to be more turbulent and sensitive to the local spatial structure. As climate change intensifies it is expected that these sheltered zones created by treeline structure will be altered and become more essential for seedling establishment.

  • Thumbnail for The Implementation of a Methodology to Measure and Analyze the Effects of Inquiry Teaching on Student Development of Inquiry Skills
    The Implementation of a Methodology to Measure and Analyze the Effects of Inquiry Teaching on Student Development of Inquiry Skills by Cadow, Charlotte

    Current science education standards mandate the inclusion of inquiry within curricula. However, existing research fails to address the correlation between the teaching of inquiry and the learning of inquiry skills. A unique opportunity presents itself at the Catamount Center where undergraduate students work with small groups of 5th grade students to facilitate a 4-week “Inquiry Unit.” This paper adapts and applies an existing theory by Ruiz-Primo (2010) to introduce a methodology that assesses the presence and quality of conclusion components in 5th grade inquiry papers. As a result of this research, several hypotheses have been generated regarding the successful implementation of the Inquiry Unit at the Catamount Center.

  • Thumbnail for The Environmental and Spiritual Significance of Chi’chil Bildagoteel, an Apache Sacred Site
    The Environmental and Spiritual Significance of Chi’chil Bildagoteel, an Apache Sacred Site by Lucas, Emily

    The combination of environmental and spiritual threats posed by mining on sacred geographies is exemplified in the struggle for Chi’chil Bildagoteel , or Oak Flat, a site in southeastern Arizona sacred to the San Carlos Apache Tribe that is currently threatened by an impending copper mine.

  • Thumbnail for An Examination of Bears Ears National Monument
    An Examination of Bears Ears National Monument by Pawa, Jay Zachary

    This thesis will provide background information on the region, explore the cultural and scientific significance of the area, the series of executive actions that have left the monument in limbo, the unique management structure put in place by the Obama administration, the stakeholders who advocated for and against the monument, the law and policy by which BENM was created, the legality of the executive power to modify or revoke a monument, and provide policy and management recommendations that could ensure the protection of the monument moving forward. Through this exploration, it will become apparent that for a number of environmental, cultural, political, and legal reasons BENM should be upheld as it was originally designed by monument proponents and established by the Obama administration.

  • Thumbnail for The Past and Future of Wildfire in the Colorado Springs Wildland-Urban Interface
  • Thumbnail for A Trophic Cascade and the Potential Consequences of Trophic Downgrading: The Cougar-Elk-Aspen System
    A Trophic Cascade and the Potential Consequences of Trophic Downgrading: The Cougar-Elk-Aspen System by Camp, Bryson Sawyer

    A trophic cascade can be defined as a specific food web or trophic structure where a predator preys on a herbivorous consumer which forages on a local vegetative resource; therefore, in this type of trophic structure top-down processes allow carnivorous apex predators to have indirect effects on local vegetative resources through their effects on the density or behavior/traits of the herbivores (M. Kummel, personal communication, April 8, 2019 and Ford et. al. 2015). In the case of predation on herbivorous consumers, both density and trait mediation can indirectly effect the density and growth pattern of vegetation that correlate directly to the alteration of prey populations via density and trait mediation (Ford et. al. 2015). Cougars have been identified as one of the seven apex predators that have been specifically associated with trophic cascades based on other empirical studies (Ripple et. al. 2014). Trophic downgrading follows the same pattern as alterations to trophic cascade structures: Trophic downgrading can have numerous direct and indirect ramifications on the local ecology. Trophic downgrading has similar consequences and is defined as, “the consequences of removing large apex consumers from nature (Estes et. al. 2011, 301).” Due to the unique characteristics that define the 6th mass extinction, one species has been the cause of most of the extinctions and the period has been characterized by the extinction of various large bodied animals, addressing trophic downgrading has become a prominent issue in the management of a wide array of ecological contexts globally (Estes et. al. 2011). In addition, apex predators, like cougars, facilitate ecosystem services such as carbon storage to buffer climate change, biodiversity enhancement, the reestablishment of native plant diversity, riparian restoration, and even the regulation of diseases (Estes et. al. 2011 and Ripple et. al. 2014). Thorough analyses of cougar habitat selection are rare, and have yet to be conducted in relation to the movement of elk and the growth of aspen saplings in the Pikes Peak region of Colorado U.S.A. until now. Through this study, it was observed and statistically shown that the number of aspen saplings tends to increase in areas that correspond with preferential habitat usage of cougars; whereas, the number of aspen saplings decreases in areas that correspond with a high prominence of observed elk herbivory. Therefore, in the Cougar-Elk-Aspen system within the Pikes Peak region cougars, carnivorous apex predators, are having indirect effects on local plants through top-down processes: This is a trophic cascade scenario.

  • Thumbnail for TREE ARCHITECTURE AND SPATIAL DISTRIBUTION ON AN ADVANCING DIFFUSE TREELINE ON PIKES PEAK, CO – YOU CANT TEACH A OLD TREE NEW TRICKS, CLIMAT CHANGE ADDITION
    TREE ARCHITECTURE AND SPATIAL DISTRIBUTION ON AN ADVANCING DIFFUSE TREELINE ON PIKES PEAK, CO – YOU CANT TEACH A OLD TREE NEW TRICKS, CLIMAT CHANGE ADDITION by Smith-Miller, Maret Hawkinson

    Treelines can serve as model ecotones in their response to climate change. However, the role of tree architecture at treelines is poorly understood. This paper examines tree architectures at a fast-migrating diffuse treeline in a bowl on the western slope of Pikes Peak (Colorado). Investigating the spatial distribution of the allometric types, the relationship between the growth rate and height for each architecture type, and the impacts of the changing climate on the architectural spatial distribution. The study site was divided into an Upper Zone (UZ) and Lower Zone (LZ). We found multiple distinct architectures within this diffuse treeline. Unexpectedly, tree architectures did not follow a spatial distribution pattern of clustering or avoiding with like and or different architectures. Krummholz and Cone architectures were found growing in close proximity to one another, signifying that the upper climatic boundary at this site has advanced up in elevation. These multiple architectures are able to represent current and past climatic conditions. Advancement is occurring at such rapid rates that tree established architectures are not able to release from their path dependency. To my knowledge, this is the first study that examines multiple tree architectural types within a treeline and how they are distributed in space.

  • Thumbnail for Birthing the Border: U.S-Mexico Border, Whiteness, and Midwifery
    Birthing the Border: U.S-Mexico Border, Whiteness, and Midwifery by Murray, Nina Kilvert

    In this thesis, I conduct a transnational analysis of the racialized hierarchies I observed during my research at La Clínica, a midwifery school and birth center on the U.S.-Mexico border. The discourse surrounding La Clínica couches the border space and the clinic in benevolent terms, but interviews with students of color reveal complicated racial and class politics that mediate the clinic and their experiences learning and working there. Students of color are thus motivated to form and create varying modalities of agency in order to define their experiences on their own terms, to express gratitude, and as a vehicle for survival in a predominantly white institution.

  • Thumbnail for PARODYING POLITICS: HOW TINA FEY AND AMY POEHLER INFLUENCED POLITICAL THOUGHT DURING THE 2008 PRESIDENTIAL ELECTIONS
    PARODYING POLITICS: HOW TINA FEY AND AMY POEHLER INFLUENCED POLITICAL THOUGHT DURING THE 2008 PRESIDENTIAL ELECTIONS by Gattuso, Theresa BEssie

    This presentation presents a case study of four SNL sketches parodying the 2008 Presidential election, with particular focus on Tina Fey's impression of Sarah Palin and Amy Poehler's impression of Hilary Clinton, paying special attention to Identity Theft, Same-Gender Drag and Conceptual Differences between political and comedic spaces.

  • Thumbnail for Being a woman is murder : the Scream series, why women are being killed, and why women are watching enthusiastically
    Being a woman is murder : the Scream series, why women are being killed, and why women are watching enthusiastically by Magninie, Mandolay Marie

    My thesis aims to look at gender roles in the Scream series and how they add or subtract from the misogyny that is usually associated with the horror genre. I mostly focus on women, but the roles of men are explored too.