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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.
441

Marginal protection : sustainable development, social resilience and migration within natural protected areas of the Trans-Mexican Volcanic Belt, central Mexico

Strauss, Simon Yale. January 2006 (has links)
Natural protected areas are places intended to protect nature, but it is now accepted that their social impact must be compatible with the ideals of 'sustainable development': they must conserve nature while improving, or at least not injuring, the socio-economic status of human communities. In Mexico, recent conservation policy has emphasized the creation of biosphere reserves, a type of protected area designed as a practical application of the concept of sustainable development. Previous research has shown that in Mexico and elsewhere, such reserves are often created in areas that are environmentally marginal and where, therefore, the lives and livelihoods of inhabitants are precarious at best. This makes the dual challenges of protecting nature and aiding social and economic development particularly acute. This study explores these challenges by considering the socio-economic patterns within protected areas along the Trans-Mexican Volcanic Belt of central Mexico. The study measured sustainable development, as indexed by the Mexican government, at both the regional and local scales, combining census data and interviews with residents in the Sierra Gorda Reserve. This combination of methodologies allowed for a fuller description of the social impacts of protected areas at different scales. The study found that while overall the lives of residents in or near natural protected areas improved steadily between 1990 and 2000, these areas are also characterized by high migration levels and an aging population, which may threaten the future sustainability of these communities. The study concludes by suggesting that migration is a key factor which should be included in Mexico's assessments of sustainable development, and that the concept of a community's social resilience is extremely useful in informing future studies.
442

The effect of a marine reserve on the abundance and size of coral reef fishes in Barbados, West Indies /

Rakitin, Ana January 1994 (has links)
This study used trapping and visual census surveys to assess whether a marine reserve in Barbados effectively protected coral reef fish stocks and whether there was evidence of emigration from the reserve. Fish abundance and sizes were higher in the reserve than in surrounding non-reserve areas. Relative differences in abundance and size between reserve and non-reserve of different taxa were positively correlated to vulnerability to traps (the most common fishing method) but not to mobility of fish. Gradients of abundance across the reserve boundaries (decreasing abundance with distance from the reserve center) were apparent for total abundance but not for individual taxa. These patterns suggest that the reserve does protect fish stocks and that emigration is of minor importance.
443

The 'wylding' of Te Urewera National Park : analysis of (re)creation discourses in Godzone (Aotearoa/New Zealand)

Castagna, Christine N January 2005 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 132-136). / Also available by subscription via World Wide Web / ix, 136 leaves, bound map 29 cm
444

Identification of intertidal marine reserves – using habitat types to identify areas of high conservation value

Simon Banks Unknown Date (has links)
The goal of biodiversity conservation has been described as the conservation of diversity at three levels: ecosystem, species and genetic diversity. Developing a representative system of marine protected areas is considered an effective way to achieve this goal in the marine environment. The growing concern associated with threats to the marine environment has resulted in an increased demand for marine reserves (i.e. no-take areas) that conserve representative and adequate examples of biodiversity. Often, the decisions about where to locate reserves must be made in the absence of detailed information on the patterns of distribution of the biota. Alternative approaches are required that include defining habitats as surrogates for biodiversity. The development of biodiversity surrogates at fine-scales (i.e. habitats) will have an increasingly important role in the identification of sites that will contribute to a representative system of marine protected areas. This is because it will increase the likelihood that the system will adequately achieve biodiversity objectives by ensuring protection of a greater range of habitats and species. Surrogate measures of biodiversity enable decisions about where to locate marine reserves to be made more reliably in the absence of detailed data on the distribution of species. There is concern, however, about the reliability of surrogate measures to represent biotic diversity and the use of such measures in the design of marine reserve systems. Currently, surrogate measures are most often based on broad-scale (100s to 1000s of kilometres) bioregional frameworks that define general categories (sandy beach, rocky shore) for intertidal systems. These broad-scale categories are inadequate when making decisions about conservation priorities at the local level (10s to 100s of metres). This study provides an explanation of an intertidal shoreline habitat surrogate (i.e. shoreline types) used to describe 24,216 kilometres of Queensland’s coastline. The protective status of shoreline types was evaluated to assist with designing a representative system of intertidal marine protected areas. The shoreline types derived using physical properties of the shoreline were used as a surrogate for intertidal biodiversity to assist with the identification of sites for inclusion in a candidate system of intertidal marine reserves for 17,463 kilometres of the mainland coast of Queensland, Australia. This represents the first systematic approach, on essentially one-dimensional data, using fine-scale (10s to 100s of metres) intertidal habitats to identify a system of marine reserves for such a large length of coast. A range of solutions would provide for the protection of a representative example of shoreline types in Queensland. Shoreline types were used as a surrogate for intertidal biodiversity (i.e. habitats, microhabitats) to assist with the identification of sites to be included in a representative system of marine reserves in south east Queensland. The use of local-scale shoreline types increased the likelihood that sites identified for conservation achieved representation goals for the mosaic of habitats and microhabitats, and therefore the associated biodiversity present on rocky shores, than that provided by the existing marine reserve protection in south east Queensland. These results indicate that using broad-scale surrogate measures (rocky shore, sandy beach) for biodiversity (habitats, microhabitats and species) are likely to result in poor representation of fine-scale habitats and microhabitats, and therefore intertidal assemblages in marine reserves. When additional fine-scale data were added to reserve selection the summed irreplaceability of 24% (for spatial extent of habitats), and 29% (for presence/absence of microhabitats) of rocky shore sites increased above zero, where a value close to one means a site is necessary, for inclusion in a reserve system, to meet conservation targets. The use of finer-scale physical data to support marine reserve design is more likely to result in the selection of reserves that achieve representation at habitat and microhabitat levels, increasing the likelihood that conservation goals will be achieved. The design and planning of marine and terrestrial protected areas systems should not be undertaken independently of each other because it is likely to lead to inadequate representation of intertidal habitats in either system. The development of reserve systems specially designed to protect intertidal habitats should be integrated into the design of terrestrial and marine protected area systems. Marine reserve networks are a necessary and effective tool for conserving marine biodiversity. They also have an important role in the governance of oceans and the sustainable management of marine resources. The translation of marine reserve network theory into practice is a challenge for conservation practitioners. Barriers to implementing marine reserves include varying levels of political will and agency support and leadership, poorly coordinated marine conservation policy, inconsistencies with the use of legislation, polarised views and opposition from some stakeholders, and difficulties with defining and mapping conservation features. The future success of marine reserve network implementation will become increasingly dependent on: increasing political commitment and agency leadership to remove conflicts within and between government agencies involved in site identification and selection; greater involvement and collaboration with stakeholders; and the provision of resources to define and map conservation features. Key elements of translating marine reserve theory into implementation of a network of marine reserves are discussed based on approaches used successfully in New Zealand and New South Wales (Australia).
445

Modelling and forecasting cultural and environmental changes

Sinay, Laura Unknown Date (has links)
Much of the discourse on cultural change has been descriptive and explanatory, with few attempts to be predictive. Where indicators of and buffers to change are identified, they tend only to be post-event assessable. The need for a tool with strong predictive power is fundamental to cultural (and environmental) impact assessment and the rationale behind this developmental work. Focusing on traditional cultures and their environmental context, and based on a case study of the Juatinga Ecological Reserve, Brasil, this research advances knowledge on modelling cultural and environmental changes, and how to manage these changes for accepted goals. A heuristic tool is presented for assessing the impacts of pressures on a culture and its related environment as well as the efficacy of management responses. This tool is associated with methods to assist in developing predictive models representing the change processes. The change model building process involves consulting stakeholders as a way of integrating different perceptions, to identify pressures, responses and links associated with cultural and environmental change. This assists in creating a co-learning environment, which facilitates communication between stakeholders. The change modelling approach permits incorporation of the complexity and uncertainty of the system represented, and enables scenario analyses. These allow expected local and flow-on impacts of management interventions to be tested. This approach is more efficient than stand-alone performance indicators that do not allow for the synergic impacts of management interventions to be observed and assessed. Using the models representing the cultural and environmental change processes of the Caiçaras of the Juatinga Ecological Reserve, this research identifies that tourism is a major pressure for change (at that locality). This study also identified that tourist numbers at new and small tourism destinations, as well as on a continental scale, can be forecast using exponential and polynomial functions. Yet, tourism flow may be perturbed at any given time by, for example, acts of violence and when the type of marketing changes. In addition, tourist numbers cannot be greater than the total population, therefore it cannot grow indefinitely as exponential and polynomial functions suggest. Hence, the use of exponential and polynomial functions to forecast tourist numbers is more reliable for short periods, such as four or five years, and when based on six or more sets of data points. The greatest contribution of this research to the cultural change discourse is its innovative approach to study, forecast and manage cultural and environmental changes. The continuation of this research may lead to identifying general theories relating pressures and responses to indicators of cultural and environmental changes.
446

Mathematical applications for conservation ecology : the dynamics of tree hollows and the design of nature reserves / Ian R. Ball.

Ball, Ian R. (Ian Randall) January 2000 (has links)
Bibliography: leaves 170-179. / vi, 179 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes a deterministic computer model for simulating forest dynamics which is the applied to a number of different timber harvesting scenarios in the mountain ash (Eucalyptus regnans F.Muell.) forests of Victoria, south-eastern Australia. Also looks at a number of new mathematical problems in the design of nature reserve systems. / Thesis (Ph.D.)--University of Adelaide, Depts. of Applied Mathematics, Environmental Science and Management, 2000?
447

Modelling and forecasting cultural and environmental changes

Sinay, Laura Unknown Date (has links)
Much of the discourse on cultural change has been descriptive and explanatory, with few attempts to be predictive. Where indicators of and buffers to change are identified, they tend only to be post-event assessable. The need for a tool with strong predictive power is fundamental to cultural (and environmental) impact assessment and the rationale behind this developmental work. Focusing on traditional cultures and their environmental context, and based on a case study of the Juatinga Ecological Reserve, Brasil, this research advances knowledge on modelling cultural and environmental changes, and how to manage these changes for accepted goals. A heuristic tool is presented for assessing the impacts of pressures on a culture and its related environment as well as the efficacy of management responses. This tool is associated with methods to assist in developing predictive models representing the change processes. The change model building process involves consulting stakeholders as a way of integrating different perceptions, to identify pressures, responses and links associated with cultural and environmental change. This assists in creating a co-learning environment, which facilitates communication between stakeholders. The change modelling approach permits incorporation of the complexity and uncertainty of the system represented, and enables scenario analyses. These allow expected local and flow-on impacts of management interventions to be tested. This approach is more efficient than stand-alone performance indicators that do not allow for the synergic impacts of management interventions to be observed and assessed. Using the models representing the cultural and environmental change processes of the Caiçaras of the Juatinga Ecological Reserve, this research identifies that tourism is a major pressure for change (at that locality). This study also identified that tourist numbers at new and small tourism destinations, as well as on a continental scale, can be forecast using exponential and polynomial functions. Yet, tourism flow may be perturbed at any given time by, for example, acts of violence and when the type of marketing changes. In addition, tourist numbers cannot be greater than the total population, therefore it cannot grow indefinitely as exponential and polynomial functions suggest. Hence, the use of exponential and polynomial functions to forecast tourist numbers is more reliable for short periods, such as four or five years, and when based on six or more sets of data points. The greatest contribution of this research to the cultural change discourse is its innovative approach to study, forecast and manage cultural and environmental changes. The continuation of this research may lead to identifying general theories relating pressures and responses to indicators of cultural and environmental changes.
448

Mathematical applications for conservation ecology : the dynamics of tree hollows and the design of nature reserves / Ian R. Ball.

Ball, Ian R. (Ian Randall) January 2000 (has links)
Bibliography: leaves 170-179. / vi, 179 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes a deterministic computer model for simulating forest dynamics which is the applied to a number of different timber harvesting scenarios in the mountain ash (Eucalyptus regnans F.Muell.) forests of Victoria, south-eastern Australia. Also looks at a number of new mathematical problems in the design of nature reserve systems. / Thesis (Ph.D.)--University of Adelaide, Depts. of Applied Mathematics, Environmental Science and Management, 2000?
449

Systematic Marine Reserve Design

Stewart, Romola Russell Unknown Date (has links)
Since the first reserve selection algorithm was developed in the early 1980s, systematic approaches to reserve design have attracted widespread support due to their ability to identify repeatable and efficient solutions to conservation planning problems. Yet there has been limited application of these methods to the problem of designing reserve systems for biodiversity conservation in the marine environment. In my dissertation research, I apply systematic methods to examine four fundamental issues in marine reserve system design. These issues consider how conservation planning outcomes are influenced when design constraints such as spatial compactness, efficiency, economic costs and incremental reserve establishment are formulated as part of the reserve design problem. First, I consider the trade-offs between spatial design and cost efficiency. In particular, I examine how well marine reserve systems can satisfy the design requirement to minimise the degree of fragmentation whilst minimising reserve system cost. In this case cost refers to the number of sites required to achieve biodiversity conservation objectives. The second issue is the inefficiency of ad hoc marine reserve system design. In terrestrial systems, ad hoc reserve design has been shown to produce inefficient reserve systems, limiting opportunities to achieve conservation targets. I examine how efficiently South Australia’s existing marine reserves contribute to quantitative conservation targets and introduce a new measure of irreplaceability. This metric reflects the potential value of a site’s contribution to reservation goals, by assessing whether a site is selected more than could be expected from chance alone. Sites selected as often as would be expected by chance, fail to contribute to the design of efficient marine reserve systems and represent an opportunity cost. The third issue addresses the demands on reserve systems to achieve both conservation and socio-economic objectives. Options for the design of marine reserve systems, which achieve better economic outcomes for commercial users without compromising conservation targets, are examined using a cost function that serves to make trade–offs early in the design process. The fourth issue is one of shifting targets and incremental reserve design. The problem was most recently highlighted with the rezoning of the Great Barrier Reef Marine Park, where the amount of no-take areas increased from 5% to over 30% but the original zoning arrangements were left in place. The consequence this has on the efficiency of the final marine reserve system is examined when different starting targets are used as the base. Each issue is examined by formulating planning scenarios using data for South Australia’s state waters as a case study. The marine reserve systems are configured using the mathematical optimisation program MARXAN to examine the complex trade-offs of conservation planning problems. The program offers the flexibility to incorporate new approaches and developing theory in marine conservation into the formal statement of the reserve design problem. The results offer some important insights for the future of marine reserve system design. These include 1) efficient representation of biodiversity is only part of the reserve design problem, with small increases in reserve system cost reported as a trade-off for more spatially compact marine reserve systems, 2) despite spanning less than 4% of South Australian state waters, the existing ad hoc marine reserves presented considerable opportunity costs that did not improve even when conservation targets were increased. Hence ad hoc reserve selection is likely to constrain effective conservation of marine biodiversity by compromising the ability to select more suitable sites, 3) integrating conservation and socio-economic objectives presents opportunities to design representative, efficient and practical marine reserve systems that minimise potential loss to commercial users with only small increases to the areal extent of the reserve system and 4) incrementally changing target levels of reservation has a minor affect on the efficiency of the final reserve system, though is likely to influence which planning units are in the final reserve system.
450

Draft forest management plan for Cashmere Forest, Port Hills, Canterbury

Mansell, Jeremy. January 2006 (has links)
Thesis (M. For. Sc.)--University of Canterbury, 2006. / Title from PDF title page (viewed on Feb. 9, 2008). Includes bibliographical references (leaves 170-175). Also issued in print.

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