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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.
901

Modeling Long-Term Changes, 1958-2011, In The Reproduction And Territory Dynamics Of Bald Eagles Of Florida Bay, Southern Coastal Everglades

Unknown Date (has links)
As top-level piscivores, Bald Eagles are a compelling subject for the study of territory dynamics and are highly representative of the distinctive suite of avian species that occupy Florida Bay. Despite successful recovery of Bald Eagles (Haliaeetus leuocephalus) throughout the species range, the population breeding within Florida Bay has not mirrored this trend. Beginning in the late 1980s, Florida Bay has suffered in its capacity to support species diversity and abundance as a result of extreme changes in hydrology related to altered flows of incoming freshwater. In fact, Bald Eagle territory use in Florida Bay has declined by as much as 43% as year to year variation and sensitivity to transitions between territory states have increased. Florida Bay’s populations of other large, conspicuous fish-eating birds, including Ospreys, Great White Herons, Roseate Spoonbills, and Reddish Egrets each exhibit a similar pattern of decline. The effects of environmental degradation throughout Florida Bay are magnified at higher trophic levels. The negative trend in territory occupancy is most pronounced in southeast Florida Bay whereas effects on territory occupancy in the northwest are minimal. The presence of spatial patterns in territory occupancy, despite regionally available breeding birds, suggests that individuals are evaluating differences in habitat quality for which certain territories are no longer considered viable. Building on our current understanding of the health of this population of Bald Eagles, we have successfully implemented modeling approaches that identify key territory breeding decisions. Loss of early breeding season activity (occupied and active territories) despite maintaining high breeding success indicates that changes in territory dynamics are the result of a failure to breed and not a reproductive failure. As such, future conservation actions should promote early breeding season activity (decisions by breeding pairs to initiate nesting) in areas of Florida Bay that were historically occupied but are now abandoned. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
902

Mechanisms Controlling Distribution of Cosmopolitan Submerged Aquatic Vegetation: A Model Study of Ruppia maritima L. (widgeongrass) at the Everglades-Florida Bay Ecotone

Unknown Date (has links)
Aquatic plants and submerged aquatic vegetation (SAV) are some of the most wide-ranging species and create important habitat for fish and wildlife in many ecosystems, including highly variable coastal ecotones. Mechanistically understanding factors controlling current distributions of these species is critical to project future distribution and abundance under increasing variability and climate change. I used a population-based approach to quantify the effects of spatial and temporal variability on life history transitions of the SAV Ruppia maritima L. (widgeongrass) in the highly dynamic Everglades-Florida Bay ecotone as a model to (1) examine which life history stages were most constrained by these conditions and (2) determine how management can promote life history development to enhance its distribution, an Everglades restoration target. Ruppia maritima life history transitions were quantified in a series of laboratory and field experiments encompassing a ra nge of abiotic and biotic factors known to affect seagrass and SAV (salinity, salinity variability, temperature, light and nutrients and seed bank recruitment and competition). These studies revealed that R. maritima life history varied east to west across the Everglades ecotone, driven by multiple gradients in abiotic factors that constrained different life history transitions in distinct ways. Based on this examination, persistence of SAV populations from dynamic coastal environments is highly dependent on large reproductive events that produce high propagule densities for recruitment. Large productive meadows of SAV also depend on high rates of clonal reproduction where vegetation completely regenerates in a short amount of time. Therefore, in hydrologically variable systems, maintenance or increases in SAV reproduction is required for population persistence through recruitment. However, SAV communities that do not experience high rates of sexual reproduction are dependent on successful seed germination, seedling and adult survival and clonal reproduction for biomass production and maintenance. Seedling survival and to a lesser extent, adult survival, are bottlenecks that can limit life history transitions under highly variable hydrological conditions. To ensure long-term survival in these communities, management activities that increase survival and successful life history development through these critical stages will be beneficial. If not, SAV populations may become highly reduced and ephemeral, providing less productive habitat. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
903

School health nurses' role in managing school programmes to prevent drug abuse

Madikane, Abegail 04 1900 (has links)
The purpose of this study is to explore and describe the nature and extent of school health nurses’ roles and responsibilities in the prevention of drug abuse by learners in schools. The study was conducted at two high schools in Eldorado Park Extension 4 (Region G), in Johannesburg West. A mixed-methods (triangulated) research approach was opted for, in terms of which structured focus group interviews, self-administered questionnaires, and participant observations optimised and complemented the data collection process. The non-probability simple random sampling technique was utilised to select 35 research participants consisting of 9 (nine) educators, 1 (one) school health nurse and 25 community healthcare workers. The 1 (one) school health nurse and the 25 community-based healthcare workers were involved in the study by means of structured self-administered questionnaires, while the nine (9) educators (who were not part of the 26) only participated in the study’s two focus group interview sessions. Among others, the study’s findings indicate that the distribution of professionally trained and registered school health nurses is not yet proportionally commensurate to addressing the problem of drug and substance abuse in schools. There has been a need to augment the shortage of school health nurses with community-based school health workers. / Health Studies / M.A. (Nursing Science)
904

Old thoughts in new ideas : Tagbanua forest use and state conservation measures at Puerto Princesa Subterranean River National Park, Palawan Island, Philippines

Dressler, Wolfram Heinz January 2005 (has links)
No description available.
905

Sports Hall of fame: a sports and museum complex on Victoria Park

陸慶邦, Luk, Hing-pong, Jimmy. January 1998 (has links)
published_or_final_version / Architecture / Master / Master of Architecture
906

Taming the lions and the lies : a review of Pennsylvania State University's crisis response strategies

Chynoweth, Sally Anne 14 December 2013 (has links)
This thesis examined how Pennsylvania State University administrators managed the Sandusky sex abuse scandal in 2011. Coombs’ (2006) Situational Crisis Communication Theory (SCCT) strategic response strategies were the theoretical basis for this thesis. This study found Penn State primarily demonstrated the corrective action response strategy. This content analysis also uncovered the dominant tone of Penn State’s messages, which was a traditional public relations tone, as defined by Fitzpatrick and Rubin (1995). This content analysis focused on newspaper articles between November 5, 2011 and January 22, 2012, which were collected from The New York Times and State College’s local newspaper the Centre Daily Times that were reporting on the Sandusky crisis. / Department of Journalism
907

Urban Greenspace, Civil Society and Science: The Creation and Management of the Rouge Park, Ontario, Canada.

Macaraig, John Marvin Rodriguera 08 August 2013 (has links)
Earth is becoming more urban. As the human population continues the current trend of migrating towards urbanized regions, the pressures to develop urban greenspaces will inevitably increase. Greenspaces play a critical role in urban livability for both human and non-human beings. This research examines the creation and management of the Rouge Park (Ontario, Canada), which is a large greenspace approximately 46 km2 located in the eastern portion of the Greater Toronto Area. The output of this research consists of three parts. The first provides an identification of the relevant actors, and a detailed chronology of the social and political events that led to the establishment of the Rouge Park. The second section explores the competing narratives of science, conservation, and development that were fundamental in shaping the protected area that we see today. The final section examines the governance and administration of the Rouge Park, and investigates the activities and involvement of civil society actors working in its day-to-day management. Using qualitative methods, I demonstrate that science and scientific expertise can be powerful tools of legitimization for civil society actors. In particular, I examine the benefits and pitfalls of placing ecologically-based rationalizations at the forefront of conservation policy deliberations. Furthermore, I show that despite shortcomings in the governance structure of the park, the current arrangement has provided civil society actors with increased opportunities to shape their community. My results show that a locally grounded nature conservation movement can serve as a powerful motivating force for citizens to enact long-term environmental planning initiatives.
908

Urban Greenspace, Civil Society and Science: The Creation and Management of the Rouge Park, Ontario, Canada.

Macaraig, John Marvin Rodriguera 08 August 2013 (has links)
Earth is becoming more urban. As the human population continues the current trend of migrating towards urbanized regions, the pressures to develop urban greenspaces will inevitably increase. Greenspaces play a critical role in urban livability for both human and non-human beings. This research examines the creation and management of the Rouge Park (Ontario, Canada), which is a large greenspace approximately 46 km2 located in the eastern portion of the Greater Toronto Area. The output of this research consists of three parts. The first provides an identification of the relevant actors, and a detailed chronology of the social and political events that led to the establishment of the Rouge Park. The second section explores the competing narratives of science, conservation, and development that were fundamental in shaping the protected area that we see today. The final section examines the governance and administration of the Rouge Park, and investigates the activities and involvement of civil society actors working in its day-to-day management. Using qualitative methods, I demonstrate that science and scientific expertise can be powerful tools of legitimization for civil society actors. In particular, I examine the benefits and pitfalls of placing ecologically-based rationalizations at the forefront of conservation policy deliberations. Furthermore, I show that despite shortcomings in the governance structure of the park, the current arrangement has provided civil society actors with increased opportunities to shape their community. My results show that a locally grounded nature conservation movement can serve as a powerful motivating force for citizens to enact long-term environmental planning initiatives.
909

Old thoughts in new ideas : Tagbanua forest use and state conservation measures at Puerto Princesa Subterranean River National Park, Palawan Island, Philippines

Dressler, Wolfram Heinz January 2005 (has links)
This study examines how Tagbanua responses to changes in conservation approaches have shaped forest access and use in relation to the political economy of a buffer zone village on Palawan Island, the Philippines. A recent shift from "fences and fines" to "devolved" conservation at Puerto Princesa Subterranean River National Park in Cabayugan has been lauded in government and non-governmental circles to support Tagbanua livelihoods while preserving the rain forest. Concurrently, however, the Tagbanua have adjusted to migrants dispossessing them of land, controlling the trade in forest products, and the means of agricultural production. Given that conservation and local resource access and use now intersect, this study asks whether "community-based" conservation can fulfill its own objectives while addressing older disparities in social relations of production and exchange. / A history of national park and cadastral zoning has restricted Tagbanua access to forest resources while supporting settler migration onto public lands. The two-way process of park zoning and migrant control over trade and productive resources has become interrelated and shaped the evolution of conservation in Cabayugan from 1971-2001. Although older "fences and fines" criminalized traditional resource uses, such as swidden (kaingin), and supported state interests in expanding paddy rice cultivation (basakan ), newer community-based approaches have carried on this agenda. Going against its purported benefits, such conservation has supported the livelihoods of dominant households, both politically and economically. Over time, these households have used political economic opportunities to build on and influence how projects support their livelihoods, which has exacerbated socio-economic differences between both social groups. As a result, conservation practitioners have continued to tie into and support wealthier households' production, while fulfilling the state's agenda of curbing swidden. Confined to unequal trade and restrictions over swidden, Tagbanua livelihoods remain vulnerable and have difficulty sustaining paddy rice. With few options to reinvest, they fail to access those socio-political and economic networks that enable participation in projects that support more lucrative cultivation. Despite good intentions, current attempts by state practitioners and non-governmental organizations at livelihood development for conservation have proven to be more divisive than effective.
910

Modelling the effect of human-caused mortality on a lion sub-population using spreadsheets

Herrmann, Eric 03 1900 (has links)
Thesis (MScFor)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Free-ranging lions (Panthera leo) in the Kgalagadi Transfrontier Park (KTP) have been subject to persecution by farmers following livestock depredation in adjacent grazing areas. In recent years at least one adult female was killed annually from a sub-population of five boundary prides that have home ranges adjoining these livestock grazing areas. While no long-term records of human-caused mortality are available, the impact of current rates of human-caused mortality is uncertain. Female-based, age-structured models were thus used to estimate the long-term viability of the KTP lion sub-population subjected to human-caused mortality under deterministic and stochastic environmental conditions. Population parameters incorporated in the models included age-class specific natural mortality, female fecundity and birth sex ratio. In so doing sustainable threshold rates of persecution were established, so that effective conservation measures can be taken, if required, to ensure the continued survival of boundary prides in the park. Sensitivity analyses of natural survival rates indicated that adult female survivorship is the most important population parameter with respect to maintaining population viability, compared to younger female age-classes, fecundity or birth sex ratio. Hence adults were also the most sensitive age-class with respect to human-caused mortality, as adult survival repeatedly acts upon individuals with the highest reproductive value. In the deterministic model, with the most optimistic survival parameter values, fecundity and birth sex ratio (female-biased) estimates, the sub-population is only able to sustain an annual persecution of three adult females, before the sub-population exhibits a sustained decline. In the worst-case scenario, where fecundity and sex ratio estimates are at their lower extremes, the maximum sustainable age-class specific persecution rate is zero, for all age-classes. Whilst these hypothetical scenarios are unrealistic, they do highlight the extreme thresholds of potentially sustainable persecution rates. Under the most optimistic scenario using the stochastic model, the highest achievable survival probability of the sub-population, when subjected to a persecution rate of one adult annually, was 78%. Although increased fecundity and birth sex ratio biased towards females may increase the survival probability, these parameters are generally at their mean values in the long-term, and may thus not necessarily prevent a sustained population decline. The models therefore suggest that the current persecution rate of one adult annually (or 4% of the adult sub-population), appears unsustainable in the longterm. To ensure the survival of existing boundary prides and to maintain a viable subpopulation, adult lionesses should, as far as possible, be afforded protection from persecution. / AFRIKAANSE OPSOMMING: Vrylewende leeus (Panthera leo) in die Kgalagadi Oorgrenspark (KTP) is onderworpe aan vervolging deur boere as gevolg van predasie op vee in aangrensende weidingsgebiede. In onlangse jare is ten minste een volwasse wyfie uit ‘n subpopulasie van vyf troppe met loopareas wat aan die weidingsgebiede grens, jaarliks uitgewis. Geen langtermyn rekords van vrektes as gevolg van menslike oorsake is beskikbaar nie, en die impak van vrektes wat deur mense veroorsaak word, is dus onseker. Wyfie-gebaseerde, ouderdomgestruktureerde modelle is daarom gebruik om te voorspel wat die langtermyn lewensvatbaarheid is van die KTP leeu subpopulasie wat onderworpe is aan vrektes deur menslike invloede onder deterministiese en stogastiese omgewingsfaktore. Bevolkingsfaktore wat deur die modelle in ag geneem is, sluit ouderdomsgroep-spesifieke natuurlike vrektes, aanwas van wyfies en geboorte geslagsverhouding in. Sodoende is volhoubare uitwissingstempos bepaal sodat, indien nodig, effektiewe bewaringsmeganismes toegepas kan word om die voortbestaan van troppe in die grensgebiede van die park te verseker. Sensitiwiteitsanalises van natuurlike oorlewingstempos het aangetoon dat volwasse wyfies se oorlewing die belangrikste bevolkingsfaktor is om die bevolking se lewensvatbaarheid te volhou vergeleke met jonger wyfie ouderdomsgroepe, aanwas of geslagsverhouding by geboorte. Daarom was volwassenes ook die sensitiefste vir vrektes as gevolg van menslike invloede, omdat die oorlewing van volwassenes herhaaldelik inwerk op individue met die hoogste reproduktiewe waarde. In die deterministiese model met die mees optimistiese oorlewing, aanwas en geboorte verhouding (wyfie-gebasseerde) beramings, is die subpopulasie slegs in staat om ‘n jaarlikse uitwissing van drie volwasse wyfies te onderhou, voordat die sub-populasie ‘n volgehoue afname toon. In die uiterste geval waar aanwas en geslags verhouding skattings op die laagste is, is die maksimum volhoubare ouderdomsklasspesifieke beramings nul vir alle ouderdomsklasse. Terwyl hierdie hipotetiese senario’s onrealisties is, onderstreep dit die uiterste vlakke van potensiële volhoubare uitwissingstempos. Onder die mees optimistiese senario – ‘n uitwissingstempo van een volwassene jaarliks – met die gebruik van die stogastiese model, was die hoogste haalbare oorlewingswaarskynlikheid van die sub-populasie 78%. Alhoewel ‘n toename in aanwas en geboorte geslagsverhouding (met oorhelling na wyfies), ‘n toename in oorlewingswaarskynlikheid tot gevolg kan hê, is hierdie faktore oor die algemeen gemiddeld oor die langtermyn en sal dit nie noodwendig ‘n volgehoue afname in die populasie verhoed nie. Die modelle dui daarop dat die huidige uitwissingstempo van een volwassene (of 4% van die volwasse sub-populasie) op ‘n jaarlikse grondslag onvolhoubaar is oor die langtermyn. Om die oorlewing van bestaande troppe in die grensgebiede, asook ‘n lewensvatbare subpopulasie, te verseker, moet volwasse leeuwyfies so ver as moontlik teen vervolging beskerm word.

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