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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.
11

Právní úprava regulace mezinárodního obchodu s ohroženými druhy / Legal Regulation of International Trade in Endangered Species

Galis, Richard January 2016 (has links)
The purpose of the thesis is to describe international, EU and Czech wildlife trade laws by identifying the regulatory measures established at these levels of law and examining them from the perspective of each. It further seeks to analyze how CITES obligations governing these measures are incorporated into the EU and Czech legislation and investigate whether they are likely implemented inadequately or, conversely, more strictly. Additionally, it points out some of the potential problems of the current legal framework as well. The thesis is composed of six chapters. Chapter one explains the goals of environmental policy in the area of nature conservation and biodiversity protection related to wildlife trade and reasons for the very existence of its regulation. Chapter two is concerned with general aspects of wildlife trade law such as its objective, purpose, principles and role within environmental law. Chapter three outlines the main and also some other relevant sources of law. Chapter four determines the principal regulatory measures which are contained within the legal regime in order to enable it to achieve its objectives. The fifth chapter then focuses on two groups of legal means designed to ensure the compliance of CITES parties and to enforce the provisions of EU and Czech wildlife trade legislation...
12

Pollinators in Urban Landscapes : Local and landscape factors impact on pollinator species richness and abundance

Rehn, Felicia January 2019 (has links)
Increasing human populations results in fast-growing urbanization. Natural and semi-natural landscapes are replaced with urban landscape features like roads, sidewalks, industrial and residential buildings. The remnants of the natural landscapes are left fragmented and are often managed by frequent mowing and trimming of the vegetation. This development has had a negative impact on pollinators such as bees and wasps. Bees and wasps are pollinating insects providing an ecosystem service that sustain the global food supply. Pollinators are important also in urban landscapes where their services are needed for ecological stability and biodiversity. This study compares 23 locations in Sollentuna municipality, to investigate if species richness and abundance of bees and wasps are correlated with local factors, landscape factors or both. The available food resources are measured in buffer zones with 200m radius. Local variables are: dead wood, exposed sand, extended edge zones, flowering plant species richness and unmanaged habitat. The result showed that the landscape factor of food availability was more important for the abundance of pollinators while local variables together with the landscape factor of food availability had a positive effect on the species richness.
13

Restoration of threatened species populations: tuatara rehabilitations and re-introductions

Ussher, Graham January 1999 (has links)
The role of scientific theory in encouraging greater efficiency and accountability for the restoration of threatened species populations is assessed for an endemic New Zealand reptile, the tuatara Sphenodon spp. The value of examining assumptions underlying concepts such as 'habitat requirements' theory and incorporating scientific principles into species recovery are discussed and perceived habitat needs for tuatara tested through experimental application. Species restoration in New Zealand, especially re-introductions, are typically undertaken as one-off, non-replicated, management exercises (trials). The lack of comparative controls for trials means that the reason for success or failure of management actions cannot be identified accurately and therefore, cannot be used to improve the probability of success for subsequent re-introductions. Trials also reinforce conservative re-introductions of species to habitats in which species are known to survive, because the risk of failure is inherently lower than re-introductions to dissimilar habitats where habitat suitability is unknown. An alternative approach is to plan management actions as experiments. Testing the full range of perceived habitat needs of species as experimental comparisons identifies the relative importance of tested factors (e.g. predators, refuges) for species recovery and identifies new management strategies (e.g. reduced level of predator control). Constructing testable hypotheses for the environmental factors thought to affect the success of restoration projects for tuatara identifies (among others) three factors: 1. absence of the introduced rat, the kiore (Rattus exulans) 2. presence of seabird colonies 3. presence of open canopy forest The threat posed by kiore to established tuatara populations was investigated by determining the existence and degree of food competition before and after an eradication program for kiore on offshore islands. Kiore successfully out-competed tuatara for favoured food items, but the degree of competition differed between forest types. Competition for food was greater in the early regenerating forest than the mature forest. These data support models which propose that kiore are but one of a number of historical and current environmental factors influencing the persistence of native fauna and that management tools other than eradication may enable restoration of fauna in the presence of kiore. To test the importance of two environmental factors, forest development and the availability of refuges, in determining the establishment of new populations of tuatara, a planned experimental reintroduction was conducted on Moutohora Island. Tuatara were released into sites where the forest was young with a closed canopy and older with a more open canopy, and in sites where refuges (seabird burrows) were distributed evenly at high densities and where burrows clumped with few burrows between patches. Vegetation age and burrow dispersion had no measurable effect on the survivorship or condition of tuatara. Although tuatara released in areas where burrows were clumped dispersed significantly further from their release points and continued to disperse away from release sites throughout the study, tuatara in all release sites were considered to still be reproductively viable 16 months after the re-introduction. Therefore, sites which support open and closed canopy forest, and seabird burrows at high and low densities should be considered as habitat options for future reintroductions of tuatara. Testing habitat needs as well-planned experiments offer more reliable information to guide future reintroductions than that generated by trial releases or releases to similar locations. Future reintroductions of tuatara and other wildlife should be designed as experiments to test declared mixes of habitat factors. This will accelerate species recovery by identifying important habitat prerequisites for re-introduction and management options for achieving these, thus refining criteria used for selecting new sites and increasing confidence, efficiency and accountability of subsequent management actions. An example of designing re-introductions as experiments is included as a plan for the re-introduction of tuatara to Tiritiri Matangi Island.
14

Restoration of threatened species populations: tuatara rehabilitations and re-introductions

Ussher, Graham January 1999 (has links)
The role of scientific theory in encouraging greater efficiency and accountability for the restoration of threatened species populations is assessed for an endemic New Zealand reptile, the tuatara Sphenodon spp. The value of examining assumptions underlying concepts such as 'habitat requirements' theory and incorporating scientific principles into species recovery are discussed and perceived habitat needs for tuatara tested through experimental application. Species restoration in New Zealand, especially re-introductions, are typically undertaken as one-off, non-replicated, management exercises (trials). The lack of comparative controls for trials means that the reason for success or failure of management actions cannot be identified accurately and therefore, cannot be used to improve the probability of success for subsequent re-introductions. Trials also reinforce conservative re-introductions of species to habitats in which species are known to survive, because the risk of failure is inherently lower than re-introductions to dissimilar habitats where habitat suitability is unknown. An alternative approach is to plan management actions as experiments. Testing the full range of perceived habitat needs of species as experimental comparisons identifies the relative importance of tested factors (e.g. predators, refuges) for species recovery and identifies new management strategies (e.g. reduced level of predator control). Constructing testable hypotheses for the environmental factors thought to affect the success of restoration projects for tuatara identifies (among others) three factors: 1. absence of the introduced rat, the kiore (Rattus exulans) 2. presence of seabird colonies 3. presence of open canopy forest The threat posed by kiore to established tuatara populations was investigated by determining the existence and degree of food competition before and after an eradication program for kiore on offshore islands. Kiore successfully out-competed tuatara for favoured food items, but the degree of competition differed between forest types. Competition for food was greater in the early regenerating forest than the mature forest. These data support models which propose that kiore are but one of a number of historical and current environmental factors influencing the persistence of native fauna and that management tools other than eradication may enable restoration of fauna in the presence of kiore. To test the importance of two environmental factors, forest development and the availability of refuges, in determining the establishment of new populations of tuatara, a planned experimental reintroduction was conducted on Moutohora Island. Tuatara were released into sites where the forest was young with a closed canopy and older with a more open canopy, and in sites where refuges (seabird burrows) were distributed evenly at high densities and where burrows clumped with few burrows between patches. Vegetation age and burrow dispersion had no measurable effect on the survivorship or condition of tuatara. Although tuatara released in areas where burrows were clumped dispersed significantly further from their release points and continued to disperse away from release sites throughout the study, tuatara in all release sites were considered to still be reproductively viable 16 months after the re-introduction. Therefore, sites which support open and closed canopy forest, and seabird burrows at high and low densities should be considered as habitat options for future reintroductions of tuatara. Testing habitat needs as well-planned experiments offer more reliable information to guide future reintroductions than that generated by trial releases or releases to similar locations. Future reintroductions of tuatara and other wildlife should be designed as experiments to test declared mixes of habitat factors. This will accelerate species recovery by identifying important habitat prerequisites for re-introduction and management options for achieving these, thus refining criteria used for selecting new sites and increasing confidence, efficiency and accountability of subsequent management actions. An example of designing re-introductions as experiments is included as a plan for the re-introduction of tuatara to Tiritiri Matangi Island.
15

Public involvement in regional planning: A case analysis of the Wet Tropics World Heritage Area, North Queensland, Australia

Lane, Marcus B. Unknown Date (has links)
No description available.
16

Public involvement in regional planning: A case analysis of the Wet Tropics World Heritage Area, North Queensland, Australia

Lane, Marcus B. Unknown Date (has links)
No description available.
17

Restoration of threatened species populations: tuatara rehabilitations and re-introductions

Ussher, Graham January 1999 (has links)
The role of scientific theory in encouraging greater efficiency and accountability for the restoration of threatened species populations is assessed for an endemic New Zealand reptile, the tuatara Sphenodon spp. The value of examining assumptions underlying concepts such as 'habitat requirements' theory and incorporating scientific principles into species recovery are discussed and perceived habitat needs for tuatara tested through experimental application. Species restoration in New Zealand, especially re-introductions, are typically undertaken as one-off, non-replicated, management exercises (trials). The lack of comparative controls for trials means that the reason for success or failure of management actions cannot be identified accurately and therefore, cannot be used to improve the probability of success for subsequent re-introductions. Trials also reinforce conservative re-introductions of species to habitats in which species are known to survive, because the risk of failure is inherently lower than re-introductions to dissimilar habitats where habitat suitability is unknown. An alternative approach is to plan management actions as experiments. Testing the full range of perceived habitat needs of species as experimental comparisons identifies the relative importance of tested factors (e.g. predators, refuges) for species recovery and identifies new management strategies (e.g. reduced level of predator control). Constructing testable hypotheses for the environmental factors thought to affect the success of restoration projects for tuatara identifies (among others) three factors: 1. absence of the introduced rat, the kiore (Rattus exulans) 2. presence of seabird colonies 3. presence of open canopy forest The threat posed by kiore to established tuatara populations was investigated by determining the existence and degree of food competition before and after an eradication program for kiore on offshore islands. Kiore successfully out-competed tuatara for favoured food items, but the degree of competition differed between forest types. Competition for food was greater in the early regenerating forest than the mature forest. These data support models which propose that kiore are but one of a number of historical and current environmental factors influencing the persistence of native fauna and that management tools other than eradication may enable restoration of fauna in the presence of kiore. To test the importance of two environmental factors, forest development and the availability of refuges, in determining the establishment of new populations of tuatara, a planned experimental reintroduction was conducted on Moutohora Island. Tuatara were released into sites where the forest was young with a closed canopy and older with a more open canopy, and in sites where refuges (seabird burrows) were distributed evenly at high densities and where burrows clumped with few burrows between patches. Vegetation age and burrow dispersion had no measurable effect on the survivorship or condition of tuatara. Although tuatara released in areas where burrows were clumped dispersed significantly further from their release points and continued to disperse away from release sites throughout the study, tuatara in all release sites were considered to still be reproductively viable 16 months after the re-introduction. Therefore, sites which support open and closed canopy forest, and seabird burrows at high and low densities should be considered as habitat options for future reintroductions of tuatara. Testing habitat needs as well-planned experiments offer more reliable information to guide future reintroductions than that generated by trial releases or releases to similar locations. Future reintroductions of tuatara and other wildlife should be designed as experiments to test declared mixes of habitat factors. This will accelerate species recovery by identifying important habitat prerequisites for re-introduction and management options for achieving these, thus refining criteria used for selecting new sites and increasing confidence, efficiency and accountability of subsequent management actions. An example of designing re-introductions as experiments is included as a plan for the re-introduction of tuatara to Tiritiri Matangi Island.
18

Restoration of threatened species populations: tuatara rehabilitations and re-introductions

Ussher, Graham January 1999 (has links)
The role of scientific theory in encouraging greater efficiency and accountability for the restoration of threatened species populations is assessed for an endemic New Zealand reptile, the tuatara Sphenodon spp. The value of examining assumptions underlying concepts such as 'habitat requirements' theory and incorporating scientific principles into species recovery are discussed and perceived habitat needs for tuatara tested through experimental application. Species restoration in New Zealand, especially re-introductions, are typically undertaken as one-off, non-replicated, management exercises (trials). The lack of comparative controls for trials means that the reason for success or failure of management actions cannot be identified accurately and therefore, cannot be used to improve the probability of success for subsequent re-introductions. Trials also reinforce conservative re-introductions of species to habitats in which species are known to survive, because the risk of failure is inherently lower than re-introductions to dissimilar habitats where habitat suitability is unknown. An alternative approach is to plan management actions as experiments. Testing the full range of perceived habitat needs of species as experimental comparisons identifies the relative importance of tested factors (e.g. predators, refuges) for species recovery and identifies new management strategies (e.g. reduced level of predator control). Constructing testable hypotheses for the environmental factors thought to affect the success of restoration projects for tuatara identifies (among others) three factors: 1. absence of the introduced rat, the kiore (Rattus exulans) 2. presence of seabird colonies 3. presence of open canopy forest The threat posed by kiore to established tuatara populations was investigated by determining the existence and degree of food competition before and after an eradication program for kiore on offshore islands. Kiore successfully out-competed tuatara for favoured food items, but the degree of competition differed between forest types. Competition for food was greater in the early regenerating forest than the mature forest. These data support models which propose that kiore are but one of a number of historical and current environmental factors influencing the persistence of native fauna and that management tools other than eradication may enable restoration of fauna in the presence of kiore. To test the importance of two environmental factors, forest development and the availability of refuges, in determining the establishment of new populations of tuatara, a planned experimental reintroduction was conducted on Moutohora Island. Tuatara were released into sites where the forest was young with a closed canopy and older with a more open canopy, and in sites where refuges (seabird burrows) were distributed evenly at high densities and where burrows clumped with few burrows between patches. Vegetation age and burrow dispersion had no measurable effect on the survivorship or condition of tuatara. Although tuatara released in areas where burrows were clumped dispersed significantly further from their release points and continued to disperse away from release sites throughout the study, tuatara in all release sites were considered to still be reproductively viable 16 months after the re-introduction. Therefore, sites which support open and closed canopy forest, and seabird burrows at high and low densities should be considered as habitat options for future reintroductions of tuatara. Testing habitat needs as well-planned experiments offer more reliable information to guide future reintroductions than that generated by trial releases or releases to similar locations. Future reintroductions of tuatara and other wildlife should be designed as experiments to test declared mixes of habitat factors. This will accelerate species recovery by identifying important habitat prerequisites for re-introduction and management options for achieving these, thus refining criteria used for selecting new sites and increasing confidence, efficiency and accountability of subsequent management actions. An example of designing re-introductions as experiments is included as a plan for the re-introduction of tuatara to Tiritiri Matangi Island.
19

Forest biodiversity maintenance : instruments and indicators in the policy implementation /

Uliczka, Helen. January 2003 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2003. / Thesis documentation sheet inserted. Appendix reproduces five published papers and submitted manuscripts, four co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.
20

Seleção de áreas prioritárias para conservação da diversidade genética para alvos múltiplos / Selection of priority areas for conservation of genetic diversity for multiple targets

PADUA, Gabriela Cristina Cantisani 01 February 2008 (has links)
Made available in DSpace on 2014-07-29T16:21:20Z (GMT). No. of bitstreams: 1 DissertacaoGabriela.pdf: 473769 bytes, checksum: 219e474c58da96099318c3d153e6e00d (MD5) Previous issue date: 2008-02-01 / Rapid urban development, due to population and economic growth, results in largescale changes in landscape. As a consequence, there is a massive extinction of species. That s why identifying networks of important areas for conserving biodiversity is important and should provide a better currency for biodiversity conservation than just keep species in isolated areas. Until recently, the methods for identifying networks for biodiversity conservation have not deal explicitly and directly with the goal of evolutionary persistence of species. Trying to achieve the adaptative diversity of each specie, data about the genetic variation of species has been incorporated into the broadscale reserve network model. Populational genetic structure and geographic range size of multiple species data were used in a reserve network plan and compared with a reserve plan that uses only ecological data such as geographic range size. The genetic variation was determined based on papers found at Institute for Scientific Information (ISI). It has been shown that when used, genetic variability data, change the location of the spatial configuration of important areas for biodiversity conservation. Concluding that genetic information is important and relevant when associated with geographical distribution, what can improve species evolutionary persistence / A perda de espécies tem alta e acelerada taxa em todos os continentes, causada, por alguns fatores, como intensificação da agricultura e o crescimento das cidades. A principal conseqüência disso é a redução da paisagem, resultando na fragmentação de habitats e gerando grandes impactos negativos para a biodiversidade. Por isso a priorização de áreas para a conservação da biodiversidade se faz essencial. A seleção destas áreas deve ser elaborada de maneira eficiente, protegendo todos os alvos de conservação com o menor custo possível. Com intuito de direcionar o foco da conservação na persistência evolutiva dos alvos, dados sobre variação genética das espécies foram utilizados de modo a tentar capturar a diversidade adaptativa de cada espécie. Para tal, dados da estrutura genética populacional de 70 espécies de mamíferos carnívoros terrestres do Novo Mundo foram incorporados à base de dados de distribuição geográfica destas mesmas espécies. Os dados da estrutura genética destas populações foram obtidos através de revisão bibliográfica. Através do site Thomson Institute ou Institute for Scientific Information foram encontrados 703 artigos referentes à estrutura genética da população das 70 espécies consideradas para o estudo. Porém apenas 24 artigos continham dados relevantes para a subdivisão genética de acordo com a variação gênica das populações das espécies. Com estes dados, foram gerados mapas de insubstituibilidade, e estes analisados de acordo com a localização espacial das células insubstituíveis. Os resultados obtidos demonstraram que, quando utilizados, os dados de variabilidade genética, mudam a configuração espacial e localização das áreas prioritárias. O que leva a concluir que são de fato importantes e relevantes quando associados aos dados de distribuição geográfica. Demonstra-se que a incorporação de dados sobre diversidade genética pode melhorar a representação da biodiversidade, e sob certos pressupostos, aumentar a persistência evolutiva dos alvos de conservação

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