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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Some soil-plant relationships of the halophyte, Salicornia europaea L.

Buratti, James Paul January 1996 (has links)
No description available.
72

The Arctic National Wildlife Refuge (ANWR): current and future concerns: varied perspectives on development

Everett, Lynn Robertson January 2007 (has links)
No description available.
73

Understanding Agency in Collective Action.

Cleaver, Frances D. January 2007 (has links)
No / Participatory approaches to natural resource management encompass ideas about the desirability of citizens actively engaging in the institutions, policies and discourses that shape their access to resources. Underpinning such approaches are assumptions about the nature of human agency. Purposive individual action is seen as instrumentally desirable as well as potentially radical and transformatory. Through participation in collective resource management it is claimed that people can re-negotiate norms, challenge inequalities, claim their rights and extend their access. This paper draws on insights from theories of structuration, governmentality and gendered empowerment to explore understandings of how individual human agency shapes and is shaped by social relationships and institutions. It outlines six factors that constrain and enable the exercise of agency for different people; cosmologies, complex individual identities, the unequal interdependence of livelihoods, structure and voice, embodiment and emotionality. The paper concludes by considering some of the implications for research and development interventions.
74

Catch share management in the Northeast multispecies fishery| Implications for the commercial groundfish fishery in New Hampshire

Feeney, Rachel Gallant 29 January 2016 (has links)
<p> This dissertation tests theories about catch share approaches to fishery management, examining their validity and limits relative to the Northeast groundfish sector program, and potentially modifies them in light of research outcomes. Participants of the groundfish fishery based in New Hampshire are the particular focus of research, but broader impacts are considered. Studies of this catch share program have been limited to date, and studies of catch share programs generally have focused on a particular dimension (e.g., biological, social, economic) rather than integrate across dimensions, despite increasing needs to do so for management. Here, six key aspects of fishing are investigated: fishing practices, social capital, bycatch, economic performance, safety, and well-being. Thus, this work is a novel contribution to the field of impact assessment research, both in its topic and scope. </p><p> The primary research question is: <i>How has the advent of catch shares impacted the Northeast commercial multispecies fishery, particularly in New Hampshire?</i> This is answered through a case study that involved a mix of quantitative and qualitative approaches, using semi-structured interviews of 2 informants, including members of groundfish sectors, common pool members, former fishermen, and fish dealers. Although social research often involves a process of theory generation, in the case of the Northeast groundfish fishery, and catch share programs more generally, a number of theories have already emerged that are ripe for testing. It was hypothesized here that fishing under the control rules governing sectors has resulted in: more efficiency and flexibility for fishermen to decide where, when, and how to fish; greater social capital among fishermen; reduced bycatch; and improved economic performance, safety, and well-being. </p><p> The groundfish fishermen of New Hampshire revealed that the theorized benefits of catch share programs do not necessarily hold true. Of the six key aspects of fishing investigated here, only the benefits related to fishing practices, bycatch and safety aligned with what has occurred in this local fishery, but even some of those benefits have qualifiers. The informants who were sector members generally felt that fishing in a sector was more efficient and flexible than the former Days-At-Sea program had been, generally due to shifting catch limits from a trip basis to an annual one. This had allowed more concentration of effort during times with greater potential for profitability (e.g., fish availability, favorable markets). Reducing bycatch was an important goal of the informants, and the sector participants indicated that their level of bycatch had decreased, primarily through eliminating the trip limits and discards of legal-sized fish. Some informants went above and beyond regulations to avoid bycatch in recognition of the need to steward stocks for the future. However, some sector members identified new pressures to discard when unobserved, driven largely by the high lease costs of choke stocks. There were no major changes in safety, because the informants largely strive to be safe no matter the management program. However, removal of trip limits for sector participants created flexibility and less pressure to fish in unsafe conditions. </p><p> Theorized benefits for social capital, economic performance, and well-being did not hold true. Despite being a novel focal point for industry organization, informants felt that sectors have not been catalysts for social capital. Rather, sectors have been based on and built off of pre-existing social capital. In some cases, social capital was reduced as increased organizational responsibilities were seen as a burden and fishing became more competitive and secretive. Economic profitability and predictability had not been realized, though the concomitant decline in, and persistently low, catch limits for certain key species (e.g., cod, yellowtail flounder) vanquished any potential that catch shares had for the economic success of this fishery. The need to lease quota of constraining stocks to harvest the available fish in one&rsquo;s own portfolio has been a substantial and new cost, with risky debt obligations, for several informants. Business predictability declined for a majority of informants. Catch shares has, however, transformed the business climate of the groundfish industry, with more focus on maximizing one&rsquo;s utility. With declines in fishery participation, and dim potential for positive economic performance, the sense of well-being and future outlook for self and fishery had diminished since the advent of the catch share program. Job satisfaction decreased for most of the sector members, and a majority of all informants said that they would not advise a young person to enter fishing. The New Hampshire-based fishermen have, on the whole, not fared as well as could be assumed based on theory, exemplifying the consequences of catch shares, the potential for declining performance by those participants unable to adapt.</p>
75

Community decisions about innovations in water resource management and protection

Houle, James J. 29 January 2016 (has links)
<p> The purpose of this study was to investigate the social, economic and technological factors that influence rates of adoption of innovative stormwater management approaches in municipal organizations in the Great Bay watershed, NH. The scope of this study was to investigate how innovations spread through municipal populations in a specific region and watershed area of the US. The methodology used mixed qualitative methods, including semi-structured interviews, case studies, and surveys to examine perceptions, attitudes, and beliefs that influence the adoption of innovative stormwater management solutions, as well as the governance characteristics of municipalities at different stages of adoption. Major findings include: adopter categories can be relatively easily and quickly categorized into early and late majorities as a preliminary means to identify populations of ready and willing audiences interested in and capable of advancing innovations; early and late adopter classifications followed general diffusion theory, but differed in substantial ways that could influence overall project or program success; and finally that early majority communities have more internal and external capacity to advance innovations as well as higher levels of peer-to-peer trust to offset perceptions related to economic risk that can either advance or stall innovative stormwater management solution adoption. This research offers insights on how to allocate scarce resources to optimally improve water quality through stormwater management solutions, and makes recommendations for how to effectively and efficiently generate greater understanding of complex barriers to adoption that thwart innovation in municipal governance organizations. One significant implication is that agents of change who want to move innovations through a broad municipal population should focus their efforts on working with innovators and early adopters that have status within relevant peer networks and who have capacity to evaluate the strengths and weaknesses of innovations.</p>
76

Estimating Seed Bank Responses to Changing Environmental Conditions in the Louisiana Coastal Zone

Horaist, David W. 28 January 2016 (has links)
<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>
77

Development of gene expression-based biomarkers of exposure to metals and pesticides in the freshwater amphipod Hyalella azteca

Gott, Ryan Christopher 29 June 2016 (has links)
<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.
78

Transboundary agreement| Case studies of marine mammal management in the bering strait

Aho, Kelsey B. 20 December 2016 (has links)
<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>
79

This Land Is Our Land| A Public Lands Oral History

Kruse, Michael 08 February 2017 (has links)
<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>
80

Dissertation Title| Framing Youth Citizen Science for Education, Youth Development, andPublic Land Conservation

Ady, Janet Carrier 11 February 2017 (has links)
<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>

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