<p> The coastal zone of Louisiana is changing due to multiple pressures associated with sea-level rise, subsidence, and the inability of sediment or organic accretion to keep pace. The expected increases in sea level and salinity may affect the distribution of the existing plant communities. In addition, these changes in the environment could lead to shifts in plant community composition. During the summer of 2014, I researched how changes in salinity and water levels may change the establishment of vegetation in Louisiana marshes. Randomly selected Coastwide Reference Monitoring System (CRMS) sites were used to collect vegetation data and soil samples. The collected soil samples from fresh, intermediate, brackish, and saline marsh sites were used in a seed bank study. The seed bank study evaluated the effects of different levels of salinity and flooding on seed germination and species richness. Seed germination was highest in soil samples collected from fresh and intermediate sites when these samples were exposed to low salinity (0.0 ppt) and non-flooded conditions. My study only found 43 seedlings in the 10 ppt treatment of 336 total seed germinations, and only 2 seedlings were found in the 20 ppt salinity treatment. Salinity was the dominant factor governing seed germinations and species richness. I also determined that the parent plants for the species found in my seed bank study were more likely to be found within the study site. However, the species data showed at least one species or genus was not present in either the historical or the field collected data. Therefore, the dispersal distance of some seeds from their parental seed provider could have been several hundred meters.</p>

<p>Ecological risk assessment (ERA) is a framework for monitoring risks of exposure and adverse effects of environmental stressors to populations or communities of interest. One tool of ERA is the biomarker, which is a characteristic of an organism that reliably indicates exposure to or effects of a stressor like chemical pollution. Traditional biomarkers which rely on characteristics at the tissue level and higher often detect only acute exposures to stressors. Sensitive molecular biomarkers may detect lower stressor levels than traditional biomarkers, which helps inform risk mitigation and restoration efforts before populations and communities are irreversibly affected. In this study I developed gene expression-based molecular biomarkers of exposure to metals and insecticides in the model toxicological freshwater amphipod Hyalella azteca. My goals were to not only create sensitive molecular biomarkers for these chemicals, but also to show the utility and versatility of H. azteca in molecular studies for toxicology and risk assessment. I sequenced and assembled the H. azteca transcriptome to identify reference and stress-response gene transcripts suitable for expression monitoring. I exposed H. azteca to sub-lethal concentrations of metals (cadmium and copper) and insecticides (DDT, permethrin, and imidacloprid). Reference genes used to create normalization factors were determined for each exposure using the programs BestKeeper, GeNorm, and NormFinder. Both metals increased expression of a nuclear transcription factor (Cnc), an ABC transporter (Mrp4), and a heat shock protein (Hsp90), giving evidence of general metal exposure signature. Cadmium uniquely increased expression of a DNA repair protein (Rad51) and increased Mrp4 expression more than copper (7-fold increase compared to 2-fold increase). Together these may be unique biomarkers distinguishing cadmium and copper exposures. DDT increased expression of Hsp90, Mrp4, and the immune response gene Lgbp. Permethrin increased expression of a cytochrome P450 (Cyp2j2) and decreased expression of the immune response gene Lectin-1. Imidacloprid did not affect gene expression. Unique biomarkers were seen for DDT and permethrin, but the genes studied were not sensitive enough to detect imidacloprid at the levels used here. I demonstrated that gene expression in H. azteca detects specific chemical exposures at sub-lethal concentrations, making expression monitoring using this amphipod a useful and sensitive biomarker for risk assessment of chemical exposure.

<p> The effectiveness of a state's natural resource management is rendered meaningless if the particular resource migrates into another state's jurisdiction. In the case of marine mammals, inadequate management of the species anywhere along their annual migration could make food insecure for the regional human populations. My research evaluates to what extent International Environmental Agreements have been able to manage transboundary challenges to food security. Two case studies, the <i>Polar Bear Agreement</i> (2000) and the <i>International Convention for the Regulation of Whaling</i> (1946), are analyzed quantitatively and qualitatively using Ronald Mitchell's four factors for describing variation of International Environmental Agreements' effectiveness: incentives, capacities, information, and norms. To ensure food security in the Bering Strait, this thesis stresses the importance of local concerns, norms and stakeholders. Transboundary management includes stakeholders at various scales to address a local challenge that is intersected by an international political boundary. The higher values of the Bowhead whale International Environmental Agreement's four factors, in the quantitative analysis, account for the higher level of food security for Bowhead whale. The qualitative analysis makes three recommendations for future International Environmental Agreements, in this case the draft U.S.-Russia agreement on Pacific walrus: 1) conservation of the Pacific walrus, 2) maintenance of Native self-determination and, 3) encouragement the flow of information between the local and federal stakeholders and between the United States and Russia. In order to ensure future food security in the Bering Strait Region, the management of the Pacific walrus depends on an effective International Environmental Agreement.</p>

<p> There are over 650 million acres of federal public lands in the United States that allow access to nature. Public lands are utilized for a variety of different activities, ranging from preservation to resource extraction. Regardless of proximity, public lands belong to everyone in the United Sates. From January to August 2016, I opportunistically and purposively collected sixteen interviews in Arizona, a state with 38.5% federal public lands, and sixteen in Texas (1.5% federal public lands), to document attitudes, opinions, and ideas about public lands in the United States. Conducting such interviews provides insight into the many different perspectives that people from different areas and backgrounds have about public land, and also acts as a medium for outreach and education. Although the data collected is not representative, it exemplifies different opinions that exist in regards to public land. Opinions such as these can affect management policy and inform how people advocate for public lands now and in the future. I attempted to capture candid responses from the interviewees utilizing an open-ended interview guide to elicit the interviewee&rsquo;s emotions, reactions, attitudes, and opinions towards public lands. All interviewees appreciated access to nature through public lands regardless of their experience with or knowledge about them. Most interviewees were familiar with national parks, but not all knew about national forests, national wildlife refuges, wilderness areas, or the national system of public lands. Several themes emerged, including issues of access, extractive industries such as grazing and mining, and discussions of federal versus state management. </p><p>

<p> This study explored how citizen science programs can connect young people with nature while providing needed scientific data. The premise was that, with attention to proper design, modification of current programming might increase citizen science outcomes for conservation. Furthermore, combining sound scientific protocols with effective education and positive youth development strategies can lead to consequential benefits for youth and society. An embedded single-case study explored a set of 20 citizen science programs relevant to the U.S. Fish and Wildlife Service to determine how the programs intended to educate and develop youth and to understand the programs&rsquo; designs. A theoretical framework based upon science education, environmental education, and positive youth development guided the inquiry. The study also explored how environmental educators, youth group leaders, scientists, and public land managers might work together to design and implement youth community and citizen science programs on federal lands. Study findings informed development of a prototype planning framework to guide planning and implementation of youth-focused community and citizen science programs on federal lands. Using the framework to design robust citizen science programs can assist scientists monitoring environmental conditions to inform land management decisions; and assist environmental education program coordinators to design meaningful service&ndash;learning activities for youth.</p><p>

<p> Feral pigs (<i>Sus scrofa</i>) are one of the most ecologically harmful species in North America and are expanding across the U.S. at alarming rates. Feral pigs are an extremely prolific, destructive species and native ecosystems will continue to suffer unless resource managers intervene to reduce the damages caused by feral pigs. In 2015, in cooperation with the Texas Parks and Wildlife Department&ndash;Kerr Wildlife Management Area, I investigated the efficacy of several novel feral pig control prototype products (i.e., toxic baits) to: 1) compare lethality and length of intoxication times between 13 microencapsulated sodium nitrite (MESN) formulations in pseudo gavage dosed captive feral pigs; 2) evaluate residual sodium nitrite levels and potential risks of vomited MESN bait on non-target species; and 3) assess the lethality of 5 unique sodium nitrite formulations in group pen feeding trials. Pseudo gavage trials resulted in 4 MESN formulations achieving a 100% lethality rate with delayed emergence of intoxication symptoms compared to previous literature. Unexpectedly, gastric coatings delayed the onset of intoxication to the same degree as enteric coatings. Vomit appeared to be positively correlated with the delivery of a lethal dose of MESN paste bait as 55/56 pigs (98.21%) vomited and died. Residual sodium nitrite in vomited bait was 90% less than the sodium nitrite concentrations in the delivered paste matrix. Despite this reduction, vomited bait could serve as a potential threat to non-target and secondary consumers, although the degradation time, residual persistence, and probability of non-target vomit consumption remains unknown. Group pen trials, testing 5 unique sodium nitrite formulations, resulted in ?80.95% overall lethality, with the greatest individual formulation lethality equaling 96.77%. Results from these studies will be beneficial in determining a MESN feral swine toxicant formulation for registration with the United States Environmental Protection Agency in the future.</p>

No description available.

<p> The U.S. federal wildland fire management system continues to experience rises in the number of acres burned annually and increases in management expenditures surrounded by firefighter death and injury. Despite a wealth of relevant academic research regarding wildland firefighting operations, a prominent nexus of these dynamics, there is little research regarding the response organization used to facilitate these operations on the fireground. Owing to a lack of research, wildland firefighting operations have remained a black box, meaning something with unknown internal workings, between the top of the response organization and the environment. From the perspective of systems thinking, the absence of a complete understanding of wildland firefighting operations prevents the dynamics of the larger domestic federal wildland fire management system from being holistically understood. In response to this gap in knowledge, this thesis explores wildland firefighting operations from an organizational perspective through a secondary analysis of qualitative data.</p>

<p> Ranching social-ecological systems (SESs) in the semi-arid, western Great Plains persist under highly variable inter- and intra-annual weather conditions and globally influenced markets. Ranch spatial scales and manager decision-making processes have traditionally been excluded from conventional grazing experiments, leading to considerable debate between scientists and land mangers about grazing strategies to achieve both beef production and biodiversity conservation outcomes on rangelands. In this dissertation I use collaborative, interdisciplinary methodologies to link rangeland and grazing management decision-making processes and learning with ecological outcomes in the semi-arid rangeland social-ecological systems (SESs) of Wyoming and Colorado. </p><p> Chapter 2 analyzes relationships between ranchers and rangeland ecosystems, inspired by the rise of adaptive management discourses in the natural resource management literature and informed by post-colonial and feminist scholarship. Rancher decision-making processes during and after drought can be understood through an ethic of care, as ranchers try to reduce social and ecological vulnerability through adaptation, learning, and respect over long-term (generations-long) time frames. Chapter 3 follows a participatory grazing research project, the Collaborative Adaptive Rangeland Management (CARM) experiment, for four years (2012-2016). I track the social learning processes of a group of 11 stakeholders representing 3 groups: ranchers, conservation NGOs, and public agencies. These stakeholders manage 10 experimental pastures in the shortgrass steppe with comparison to the traditional grazing management practice. These pastures are managed to maintain or improve a viable cattle operation, grassland bird diversity, and rangeland vegetation structure, composition, and cover. Decisions by the stakeholder group about grazing and prescribed burning illustrate the complex role of existing management knowledge in social learning and the outcomes of participatory rangeland research. </p><p> In Chapter 4, I use repeated interviews and ecological monitoring on 17 family-owned and operated ranches in eastern Colorado and eastern Wyoming to categorize different grazing management strategies and compare plant species composition outcomes across those different strategies, accounting for environmental factors. After accounting for environmental influences, using non-metric multidimensional scaling and linear mixed models, I found a reduction of perennial cool-season grasses on ranches in higher grazing stocking rates and on cow-calf/yearling operations compared to cow-calf operations, but no significant differences in plant species composition on ranches with different grazing rotation strategies or different planning styles (tacit vs. explicit planners). I classified ranches into adaptive cycle trajectories to interpret ranch decision-making in terms of ranch SES-scale resilience. In Chapter 5, I review critical social literature to reflect on my positionality as a researcher, as well as the importance of consent and respect in social-ecological research. </p><p> Findings in this dissertation provide useful information for understanding the adaptation of ranch-scale rangeland SESs. Future research or outreach projects seeking to engage with rancher stakeholders may be improved by considering complex decision-making processes, caring practices, and the stewardship ethic of ranchers. Future efforts to bring multiple public-lands stakeholder groups with different management perspectives together for adaptive management will be improved if they consider the important role of stakeholder practices and experiences with rangeland management in social learning, and commit to building trust and knowledge through engagement that extends beyond the typical 3-5 year window for grazing research projects. My investigation of ranch-SES adaptive processes illustrates diverse decision-making strategies on different ranches. More research is needed on stocking rate decision-making, including around the social and political contexts of stocking rate decisions. This work suggests that a resilience lens can contribute to existing theory on ranch adaptive decision-making. Outreach and education efforts are likely to be more successful if they consider that one size does not fit all for ranch grazing management strategies.</p>

<p> The conflict in the Pacific Northwest between competing visions of how federal forests should be managed resulted in a political stalemate in the early 1990s. The Northwest Forest Plan (NWFP) was initiated to resolve the demands for maintaining ecosystem processes and biological diversity with the social and economic needs for timber harvest. The foundation for the plan rested with the development of ecosystem management. The intent of this research is to explore the events which led up to the adoption of the NWFP, how it was implemented by the US Forest Service and Bureau of Land Management and the subsequent reactions to and consequences of the plan. </p><p> The primary research consisted of thirty-eight semi-structured interviews with individuals responsible for the development of the initial plan, those tasked with implementing the plan and current federal agency personnel from the land management agencies and regulatory agencies. With the use of thematic analysis, key meanings were captured as expressed by the interviewees. The data was analyzed using institutional theory, capturing the organizational relations within the organizational field of the land management agencies. </p><p> Research findings suggest that the NWFP was unsuccessful in meeting the goal of addressing the social and economic issues as well as the goals for ecosystem management. This dissertation explores the organizational practices and cultural meanings that led to the final instantiation of the plan. It seeks to shed light on the reasons why these goals were not met and how future forest plans can move beyond the current stalemate between conservation and preservation.</p><p>