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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.
61

Enhancing the monitoring and trapping of protected crop pests by incorporating LED technology into existing traps

McCormack, Kevin January 2016 (has links)
Management of pest species is ordinarily required in the production of protected crops. Integrated pest management (IPM) is commonly used when controlling insects. The European Union Sustainable Use Directives states that "integrated pest management’ means careful consideration of all available plant protection methods and subsequent integration of appropriate measures that discourage the development of populations of harmful organisms and keep the use of plant protection products and other forms of intervention to levels that are economically and ecologically justified and reduce or minimise risks to human health and the environment. ‘Integrated pest management’ emphasises the growth of a healthy crop with the least possible disruption to agro-ecosystems and encourages natural pest control mechanisms.” Effectively monitoring pests is a key component of IPM, with decisions to use biological control agents (BCA) and insecticides often based on the presence of pests in traps. A commonly used monitoring tool is the sticky trap; these traps are coloured and rely primarily on their visual attractiveness to the pest. The capture efficiency of sticky traps can potentially be increased with the addition of light emitting diodes (LEDs). The objective of this project was to use LEDs to enhance the efficacy of yellow sticky traps for trapping a range of insect pests, to enable more effective timing of pest management by optimising pest monitoring. The addition of LEDs may also enable more effective mass trapping via yellow sticky traps, and minimize the trapping of beneficial insects. Comparisons between standard yellow sticky traps and those equipped with green (540 nm) or blue (480 nm) LEDs were carried out at four commercial growing facilities. Green (540 nm) LED equipped traps were compared with standard yellow traps in a mass release of the biological control agent Encarsia formosa Gahan (Hymenoptera: Aphelinidae), to determine if there are negative consequences to the addition of green (540 nm) LEDs when using this biological control agent. Relative spectral preferences of western flower thrips (Frankliniella occidentalis Pergande (Thysanoptera: Thripidea)) and Glasshouse whitefly (Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae)) were determined using a choice test comparing a range of wavelengths in 20 nm steps against a control wavelength. Green (540 nm), and blue (480 nm) LED equipped traps captured significantly more dark-winged fungus gnats (Bradysia difformis Frey (Sciaridae: Diptera)) and diamondback moths (Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae)) than those without. No significant differences were found between green (540 nm) LED equipped traps and those without for E. formosa, and a significant decrease in the capture of the shore fly parasitoid Kleidotoma psiloides Westwood (Hymenoptera: Figitidae) was observed. In behavioural experiments F. occidentalis showed a peak spectral preference at 360, 420, and 480 nm, and T. vaporariorum at 320, 340, and 380 nm. The addition of LEDs to yellow sticky traps enhanced their capture efficiency for some key pests in commercial protected crop growing environments, and has the potential to enable pest detection at an early stage, consequently optimising the timing of pest management options.
62

Indications of geography? : constructions of place, boundaries, and authenticity in the UK protected food names system

Rippon, Matthew James Julian January 2013 (has links)
Geographers have investigated agri-foods, commodity chains, 'alternative' food networks, 'local' production, and multicultural cuisine. However, the relationship between food, place, boundaries, environmental determinism, and authenticity remains under-researched. This thesis seeks to redress this deficiency with a detailed study of the construction of the Protected Food Names (PFN) scheme in the UK. PFNs are a type of Intellectual Property (IP) and form the European component of the international Geographical Indications (GI) system. These place-based foods and drinks originate from defined and bounded areas and are produced in supposedly traditional ways. Their manufacturers consider them unreplicable outside the protected zone. This qualitative investigation of three PFNs – Melton Mowbray Pork Pies, Stilton Cheese, and Grimsby Traditional Smoked Fish – critiques the ways in which ideas of place, boundaries, and authenticity are invoked by producers. The thesis interrogates how manufacturers understand place and its boundedness, employ supposedly 'objective' historical evidence, and apply the ambiguous notion of authenticity to stabilise and sustain local practices. The study also examines the strategies deployed to generate consumer interest in an era where uniqueness is an important marker of value. This work thus introduces a different conceptual angle to accounts of the PFN structure which primarily privilege legal or economistic assessments. It aims instead to deconstruct the geographical concepts on which the PFN edifice is based. The ultimate aim is to draw attention to the vagaries inherent in the increasingly hegemonic GI model. This research connects with geographical debates about the construction of place and boundaries, the social production of authenticity, the role of selective historical 'facts' in the development of narratives about place, and the 'selling' of location and its products. It therefore provides a lens through which the foundations and everyday operation of the GI system can be profitably analysed.
63

Marine Reserves: Do they bring net Benefits to Economies? / Přináší mořské rezervace čistí užitek národním ekonomikám?

Tyl, Michal January 2007 (has links)
Although more than 1300 marine reserves have already been established around the world, they still present a relatively new tool for environmental conservation and fisheries management. In accordance with this new approach towards marine protection, conservationists currently call for rapid establishment of a reserve network, which would encompass 10% to 30% of the oceans. Representative habitats from coastal areas as well as high seas would be included. Such a network should serve as a haven for marine species, ensuring their sustainability and aiding them to recover from fishery pressure. Furthermore, reserves are expected to enhance yields to the fishing industry through spillover and larval export. The paper attempts to determine, whether and under which conditions do marine reserves bring net benefits to economies.
64

Landscape ecological planning for protected areas using spatial and temporal metrics

Mirkarimi, Hamed, hamed.mirkarimi@student.rmit.edu.au January 2007 (has links)
The natural characteristics of protected areas have changed for a variety of reasons through time. Changes in protected area landscapes can occur because of natural and/or cultural processes. Natural processes such as geomorphological disturbance and climatic condition can permanently and/or temporarily change the characteristics of the environment. In addition, changes in human needs, knowledge and activities are the cultural driving forces behind changing characteristics of landscape through time. These changes can be studied both spatially and temporally. Spatially, protected area landscape structures such as shape, size and location with respect to their neighbourhood context can be studied to describe landscape configuration. Temporally, landscape functions such as different geographical locations and land characteristics can be studied to determine the rate of temporal variability in landscape. Any changes in temporal characteristics may lead to changes in spatial characteristics of protected areas and vice versa. This thesis has developed a framework to enhance the landscape ecological planning approach with attention to changes in landscapes of protected areas. Considering landscape ecological concepts, this framework draws upon spatial and temporal characteristics of protected areas. Initially, a basic model of the landscape ecological approach to protected area planning and data requirements for landscape ecological planning was developed according to the concept of landscape ecological planning. In order to examine the model in the real world, the data requirements for landscape ecological planning were implemented using a case study method. The basic list of data required for landscape ecological planning was further developed through the case study approach by highlighting the importance of road metrics in the process of planning. In addition, the case study approach proved that spatial and temporal metrics can be used in the interpretation of spatial configuration and temporal variability of protected areas th rough a quantitative method. The framework was developed for three case studies in Iran and three case studies in Australia. A number of metrics were applied in order to quantify spatial and temporal aspects of the protected areas. A list of spatial and temporal criteria was developed to assist interpretation of area compaction, spatial fragmentation and temporal variability of protected areas. Using the criteria list, a new framework for spatial and temporal evaluation of protected areas has been developed. This can be used to determine spatial and temporal management issues of protected areas at the landscape scale. Then planning scenarios for spatial and temporal issues of protected areas at the landscape scale can be suggested. The developed framework has the potential to be applied to all protected areas even where detailed ecological data and information are not available. In addition, when all data required are available, the developed framework using spatial and temporal metrics has the potential to suggest a flexible zoning plan for protected areas.
65

The global network of marine protected areas: developing baselines and identifying priorities

Wood, Louisa Jane 05 1900 (has links)
Recently adopted global marine protection targets aim to protect 10-30% of marine habitats within the next 3 to 5 years. However, these targets were adopted without prior assessment of their attainability. Moreover, our ability to monitor progress towards such targets has been constrained by a lack of robust data on marine protected areas (MPAs). In this thesis I present the results of the first explicitly marine-focused, global assessment of MPAs in relation to three global marine protection targets. Approximately 2.35 million km2, equivalent to 0.65% of the world’s oceans, are currently protected, and only 12% of that is ‘no-take’. Over the last two decades, the marine area protected globally has grown at ~5% per year. At this rate, even the most modest target is unlikely to be met for at least several decades. The utility of large-scale conservation targets has been repeatedly questioned, although mainly on ecological grounds. However, if, as is suggested here, their primary role is to motivate behavioural change, then a more serious problem is that they seem to be failing in this regard, too. I explore possible reasons for this and suggest two main problems: firstly, an as yet unmet need to develop a hierarchical system of targets that reflects the multi-scale and pluralistic nature of ecological and political systems; and secondly, feedback mechanisms between political will, perceived attainability, and target formulation which may impede implementation of the targets. Since the adoption of the global targets, no implementation strategy has been developed, which may also impede target attainment. In order to fill this gap, I applied a rarity-complementarity heuristic place prioritisation algorithm (PPA) to a dataset consisting of 1038 global species distributions with 0.5° latitude/longitude resolution, under ten scenarios devised to reflect the global targets. This is the first time that species distribution ranges of marine species have been used in a globally synthetic way, and is by far the largest application of a PPA to date. Global priority areas for protection are identified for each scenario, which may be used to identify where regional-scale protected areas network design efforts might be focused.
66

Creating Partnerships Between Governmental Authorities and Indigenous peoples: a New Strategy for Biodiversity Conservation

Duboisset-Broust, Lauren January 2013 (has links)
Securing the interactions between plants, animals, microorganisms and the physical environment forms the foundation of sustainable development (Global Biodiversity Strategy, World Resources Institute, 1992). Facing the ongoing depletion of the natural resources, new strategies to ensure biodiversity conservation were developed. The establishment of protected areas by governmental authorities rarely led to successful results, in terms of environmental protection and social justice (Alcorn, 1993). A shift of thinking in the 1970s allowed the conservationists to see the indigenous peoples no longer as barrier to biodiversity conservation but as the holders of complex and historical knowledge of the natural environment. Consequently, partnerships were developed between governments and indigenous communities within the protected areas. This study investigates the results of the creation of partnership, whether it is a good means to achieve biodiversity conservation or not, and under which conditions it can be successful. It also aims to find the perceived benefits and potential limitation of cooperation. Through the analysis of two case studies: the World Heritage site in Laponia, Sweden and the Kaa-Iya del Gran Chaco National Park in Bolivia, the study finds that partnership for biodiversity conservation is utterly related to social and political claims: because a successful partnership cannot be imposed from above, a process towards indigenous peoples’ right to self-determination must be initiated.
67

From Agriculture to Ecotourism: Socio-economic Change, Community Development and Environmental Sustainability in a Costa Rican Village

Howitt, Josephine B. 30 August 2012 (has links)
This research is an ethnographic case study of the emerging ecotourism economies in the agricultural village of San Gerardo de Rivas, Pérez Zeledón, Costa Rica. Due to the village’s location as the main entry point to climb the country’s tallest mountain within Chirripó National Park, the majority of households in San Gerardo now derive some income from tourism. I conducted twenty household surveys, followed by twenty-one semi-structured interviews with male and female heads of households and representatives of local organizations and tourism businesses. Drawing on local perspectives, I found that ecotourism was a complementary income source to agriculture and that men and women were engaging differently in ecotourism employment. Local organizations were involved in the participatory management of ecotourism activities within Chirripó National Park. Ecotourism has affected environmental practices and local people are strategically negotiating the direction of tourism development, including through using environmental discourses, to optimize the benefits to their community.
68

Towards Climate Change Adaptation in Canada's Protected Natural Areas: an Ontario Parks Case Study

Lemieux, Christopher James January 2008 (has links)
Climate is a major catalyst of change in the composition, structure and function of the Ecosphere. Empirical studies of species response to climate consistently reveal that the anomalous warming occurring over roughly the past half-century is having a discernible impact on contemporary biodiversity. Climate change has also been implicated in several species extinctions, a phenomenon projected to be exacerbated in the future. These studies and events indicate that the implications of climate change for biodiversity conservation are considerable. Biodiversity conservation is one of the major modern rationales behind formal protected natural areas establishment, planning and management. However, most protected natural areas have been designed to protect in perpetuity specific natural features, species and communities in-situ, and don’t take into account shifts in ecosystem composition, structure and function that are being induced by climatic change. The ecological manifestations of climate change will be such that the established species management objectives of some protected natural areas will no longer be viable. Consequently, protected natural areas agencies will need to be adaptive in order to be able to respond to climate change-induced impacts and improve their ability to deliver their various protected natural area- and biodiversity-related mandates, such as the perpetual protection of representative elements of natural heritage. The principal goal of this dissertation was to begin the process of climate change adaptation (mainstreaming) within the Canadian protected natural areas community, thereby facilitating the ability of jurisdictions, agencies and organizations to adapt to climate change-related impacts and implement adaptation decisions. To realize this goal, four objectives were formulated: i) to synthesize the state of knowledge on climate change, biodiversity and protected natural areas policy, planning and management; ii) to establish the state of climate change adaptation with respect to Canadian protected natural areas agencies; iii) to assess the current position, priorities, and challenges of, and barriers to, Canadian protected natural areas agencies with respect to climate change adaptation; and iv) to develop a climate change adaptation portfolio and evaluate the suitability of the portfolio for implementation by a Canadian protected natural areas agency, Ontario Parks. The research revealed that while mainstreaming climate change into protected natural areas policy, planning and management will be essential for the persistence of biodiversity and the continued viability of current planning and management practices under a changing climate, there is a clear disconnect between the perceived salience of climate change and a lack of available resources (e.g., financial resources and staffing) and scientific capacity required to respond to the issue. Moreover, the limited protected natural areas climate change literature to-date provides little guidance to the planners and managers of already established protected natural areas. Accordingly, there is an indicated need to assist Canadian protected natural areas agencies in the identification and evaluation of adaptation options as a strategic starting point in working towards mainstreaming climate change into relevant program areas. In response to this indicated need, a policy Delphi survey method was used to facilitate the identification and evaluation of adaptation options tailored specifically to Ontario Parks. A panel of protected natural areas experts identified 165 adaptation options within Ontario Parks’ six major program areas [(i) Policy, System Planning & Legislation; (ii) Management Direction; (iii) Operations & Development; (iv) Research, Monitoring & Reporting; (v) Corporate Culture & Function; and (vi) Education, Interpretation & Outreach) in the first iteration of the policy Delphi. Adaptation options were subsequently evaluated individually for their perceived level of desirability, feasibility and implementation time-frame by the panel via a second iteration of the policy Delphi. In so doing, the research evaluated the relative merit (or practicality) of alternative adaptation options in these program areas in order to help identify priority (or ‘first-order’) adaptations for consideration in an official climate change adaptation strategy by Ontario Parks. The research provides a solid conceptual and methodological framework with important practical ‘lessons learned’ that will help Canadian protected natural areas jurisdictions understand, address and begin mainstreaming climate change into policy, planning and management decision-making. Collectively, the research includes the first practical discussion of adaptation to climate change within the institutional framework of any Canadian protected natural areas jurisdiction, representing a significant contribution to the protected natural areas planning literature at the science-policy interface.
69

Managing for Ecosystem Resilience in Fathom Five National Marine Park, Lake Huron, Canada

Parker, Scott Robert 15 April 2013 (has links)
Protected areas are considered to be the cornerstone of biodiversity conservation strategies and are valued sources of human well-being and ecosystem services. Yet they are not immune to the unprecedented impacts being felt worldwide. As an example, increased human activity, including development, transport of invasive species, and contributions to climate change, are transforming protected areas within the Laurentian Great Lakes into new and novel ecosystems. It is in this context of uncertainty that I explored the practice of managing for resilience. Canada’s first national marine conservation area, Fathom Five National Marine Park in Lake Huron, functioned as the study area. Besides profound and complex ecosystem change, Fathom Five is also experiencing governance challenges in the form of tangled responsibilities and issues of legitimacy. The resilience-based approach recommended elements that strengthened the capacity of the park to cope with and recover from disturbance and maintain its defining structures, functions, and feedbacks. This included a reduction of vulnerabilities (e.g., limit exposure to coastal fragmentation, manage disturbance regimes, and maintain functional and response diversity), an increase in adaptability (e.g., need to foster social learning, innovation, and improved governance structures), and an ability to navigate change (e.g., better express desired state, identify thresholds, and influence transformations), within established management practices. More specifically, methods to make spatial planning and monitoring more operational and resilience-based, were developed. For spatial planning, the decision-support tool Marxan with Zones was utilized and demonstrated how themes of representivity, replication, and connectivity could be applied in a resilience-based zoning context. For monitoring, a multivariate distance-based control chart method was developed to detect a decrease in resilience of the parks coastal wetland fish communities. Although an increase in variability was observed, a regime shift was not reported during the years investigated (2005-2012). In summary, the thesis provided an original contribution to science by examining the uncertainties and complexities facing a freshwater protected area and reframing practical conservation solutions through a resilience lens.
70

Towards Climate Change Adaptation in Canada's Protected Natural Areas: an Ontario Parks Case Study

Lemieux, Christopher James January 2008 (has links)
Climate is a major catalyst of change in the composition, structure and function of the Ecosphere. Empirical studies of species response to climate consistently reveal that the anomalous warming occurring over roughly the past half-century is having a discernible impact on contemporary biodiversity. Climate change has also been implicated in several species extinctions, a phenomenon projected to be exacerbated in the future. These studies and events indicate that the implications of climate change for biodiversity conservation are considerable. Biodiversity conservation is one of the major modern rationales behind formal protected natural areas establishment, planning and management. However, most protected natural areas have been designed to protect in perpetuity specific natural features, species and communities in-situ, and don’t take into account shifts in ecosystem composition, structure and function that are being induced by climatic change. The ecological manifestations of climate change will be such that the established species management objectives of some protected natural areas will no longer be viable. Consequently, protected natural areas agencies will need to be adaptive in order to be able to respond to climate change-induced impacts and improve their ability to deliver their various protected natural area- and biodiversity-related mandates, such as the perpetual protection of representative elements of natural heritage. The principal goal of this dissertation was to begin the process of climate change adaptation (mainstreaming) within the Canadian protected natural areas community, thereby facilitating the ability of jurisdictions, agencies and organizations to adapt to climate change-related impacts and implement adaptation decisions. To realize this goal, four objectives were formulated: i) to synthesize the state of knowledge on climate change, biodiversity and protected natural areas policy, planning and management; ii) to establish the state of climate change adaptation with respect to Canadian protected natural areas agencies; iii) to assess the current position, priorities, and challenges of, and barriers to, Canadian protected natural areas agencies with respect to climate change adaptation; and iv) to develop a climate change adaptation portfolio and evaluate the suitability of the portfolio for implementation by a Canadian protected natural areas agency, Ontario Parks. The research revealed that while mainstreaming climate change into protected natural areas policy, planning and management will be essential for the persistence of biodiversity and the continued viability of current planning and management practices under a changing climate, there is a clear disconnect between the perceived salience of climate change and a lack of available resources (e.g., financial resources and staffing) and scientific capacity required to respond to the issue. Moreover, the limited protected natural areas climate change literature to-date provides little guidance to the planners and managers of already established protected natural areas. Accordingly, there is an indicated need to assist Canadian protected natural areas agencies in the identification and evaluation of adaptation options as a strategic starting point in working towards mainstreaming climate change into relevant program areas. In response to this indicated need, a policy Delphi survey method was used to facilitate the identification and evaluation of adaptation options tailored specifically to Ontario Parks. A panel of protected natural areas experts identified 165 adaptation options within Ontario Parks’ six major program areas [(i) Policy, System Planning & Legislation; (ii) Management Direction; (iii) Operations & Development; (iv) Research, Monitoring & Reporting; (v) Corporate Culture & Function; and (vi) Education, Interpretation & Outreach) in the first iteration of the policy Delphi. Adaptation options were subsequently evaluated individually for their perceived level of desirability, feasibility and implementation time-frame by the panel via a second iteration of the policy Delphi. In so doing, the research evaluated the relative merit (or practicality) of alternative adaptation options in these program areas in order to help identify priority (or ‘first-order’) adaptations for consideration in an official climate change adaptation strategy by Ontario Parks. The research provides a solid conceptual and methodological framework with important practical ‘lessons learned’ that will help Canadian protected natural areas jurisdictions understand, address and begin mainstreaming climate change into policy, planning and management decision-making. Collectively, the research includes the first practical discussion of adaptation to climate change within the institutional framework of any Canadian protected natural areas jurisdiction, representing a significant contribution to the protected natural areas planning literature at the science-policy interface.

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