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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.
41

Cost-benefit analysis and valuation uncertainty : empirical contributions and methodological developments of a study on trade-offs between hydropower and wild salmon /

Håkansson, Cecilia, January 2007 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2007. / Includes an appendix of three papers and manuscripts, one co-authored with Per-Olov Johansson and Bengt Kriström. A second appendix reprints questionnaire used to elicit data for the three papers. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.
42

Habitat selection of hatchery and wild juvenile salmonids in Eagle Creek Basin, Oregon /

Brignon, William R. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 92-102). Also available on the World Wide Web.
43

Distribution of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoise (Neophocaena phocaenoides) in relation to physicaland biological factors in Hong Kong

Law, Man-kwan., 羅文君. January 2001 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
44

Regional Fisheries Management Organizations: is power listening to Science? / Organizações Regionais para o Ordenamento Pesqueiro: o poder está ouvindo a ciência?

Gonçalves, Leandra Regina 19 September 2016 (has links)
One of the biggest challenges in contemporary global environmental governance is the future of marine biodiversity. Over the years, increased fishing efforts in previously remote areas drove many fish stocks to scarcity. The Regional Fisheries Management Organizations (RFMOs) emerged to solve the international fishery crisis, on the assumption that they would provide a forum where Member States may agree and discuss binding rules for the conservation and management of fish stocks within its geographical area of responsibility. Although some agreements existed for more than 60 years, many authors agree that they have not been fully effective in promoting the maintenance and conservation of fish stocks. There are many reasons that might explain the lack of effectiveness, one of them being that science is not very often listened to in the political decision-making process. In this research, the influence of knowledge and science in shaping policy decisions will be observed and analyzed. Therefore, the use of the epistemic communities theory, that which forms part of the constructivist turn in international relations -- was used to answer the main question posed here: when does power listen to science? When it does, does it bring more effectiveness in terms of knowledge, input from epistemic communities, does it induce states to change their behavior, and do these influences lead to policies, which can credibly improve biomass? Using process tracing, through elite interviews, and with a systematic compilation and study of meeting reports from three RFMOs: the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR); the International Convention for the Conservation of Atlantic Tunas (ICCAT); and the Commission for the Conservation of Southern Bluefin Tuna (CCSBT), the final conclusion is that they may listen to science, but their strategy, allies, and the ways in which it occurs differ case-by-case. / Um dos maiores desafios na governança ambiental global contemporânea é o futuro dos ecossistemas e da biodiversidade marinha. Ao longo dos anos, o aumento do esforço de pesca nas áreas anteriormente remotas levou muitas populações de peixes à escassez. As Organizações Regionais para o Ordenamento Pesqueiro (OROPs) surgiram para resolver a crise internacional de pesca, através um fórum onde os Estados-Membros podem acordar e discutir regras vinculativas para a conservação e gestão dos recursos pesqueiros no âmbito da sua área geográfica de responsabilidade. Embora alguns acordos existam há mais de 60 anos, muitos pesquisadores concordam que os mesmos não têm sido totalmente eficazes para promover a manutenção e conservação dos recursos pesqueiros. Muitas razões podem explicar a falta de eficiência no manejo, uma delas é que, o aconselhamento cientifico não é muitas vezes considerado nas decisões políticas. Nesta pesquisa, a influência do conhecimento e da ciência na tomada de decisões políticas serão avaliadas. Para isso, a teoria das comunidades epistêmicas, que faz parte da veia construtivista em Relações Internacionais, foi usada para responder à principal questão colocada aqui: quando é que o poder ouviu a ciência? E isso trouxe mais eficiência em termos do conhecimento proveniente das comunidades epistêmicas induzir os Estados a mudarem seu comportamento e a influência levar a políticas que aumentem a biomassa dos estoques pesqueiros? Com o uso de process tracing, por meio de entrevistas com atores e uma compilação sistemática dos relatórios das reuniões anuais, as OROPS: CCAMLR, ICCAT e CCSBT foram estudadas, e a conclusão final é que, os tomadores de decisão podem ouvir a ciência, porém, a estratégia, os aliados e a forma como a influência se desenvolve varia caso a caso.
45

Fisheries data requirements under international law achieving long-term conservation and sustainable use of tuna fisheries in the western central Pacific Ocean /

Manarangi-Trott, Lara. January 2008 (has links)
Thesis (Ph.D.)--University of Wollongong, 2008. / Typescript. Includes bibliographical references: p. 401-424.
46

Age, growth and yield-per-recruit analysis of ndunduma Diplotaxodon limnothrissa (Teleostei: Cichlidae), in the southeastern arm of Lake Malawi

Kanyerere, Geoffrey Zantute January 2004 (has links)
Diplotaxodon limnothrissa Turner (1995) is a widely distributed species occurring throughout Lake Malawi, extending from the surface to a depth of at least 220m. It is probably the most abundant cichlid in the lake with biomass estimates of around 87 000 tonnes in the pelagic zone alone. The species is exploited commercially in the southern part of the lake but since its inception the fishery has never been assessed. As such this study investigates some aspects of age and growth of the species besides applying a yield-per-recruit analysis to assess the status of the fishery. Analysis of sectioned sagittal otoliths revealed that D. limnothrissa is fast growing and relatively long-lived species, attaining ages in excess of 10 years. Growth in length was rapid in immature fish, with fish attaining almost half of their maximum size within their first year. Le ngth-at-age was described by the von Bertalanffy growth model with combined-sex growth described as Lt = 211.21(1-exp(- 0.24(t+1.36))) mm TL. Total, natural and fishing mortalities were estimated at 0.76 yr⁻¹, 0.31 yr⁻¹ and 0.45 yr⁻¹ respectively. Per-recruit analysis indicated that the D. limnothrissa stock in the southeast arm of the lake is fully exploited as indicated by the current spawner biomass-per-recruit ratios of 31-55% (SB/R)F=0. Modelling indicated that the current age-at-capture (2.67 years) is lower than the age at which yield is optimised (> 5 years) based on the F₀·₁ harvesting strategy. It is, therefore, recommended that the age-at-capture should be increased from 2.67 to 5 years to optimise yield.
47

Dano genômico e o status de conservação de Mugil curema (Actinopterygil: Mugilidae) em cinco sistemas estuarinos do Estado de Pernambuco

LIMA, Anderson Rodrigues Balbino de 17 February 2016 (has links)
Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-08-30T18:08:06Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação (Anderson Rodrigues).pdf: 1100092 bytes, checksum: 006b7ba8f56e81d9066bc271f99edcbe (MD5) / Made available in DSpace on 2016-08-30T18:08:06Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação (Anderson Rodrigues).pdf: 1100092 bytes, checksum: 006b7ba8f56e81d9066bc271f99edcbe (MD5) Previous issue date: 2016-02-17 / FACEPE / A perda da diversidade biológica pode ser um reflexo da degradação ambiental, principalmente em locais com grandes contingentes demográficos. No Nordeste do Brasil, a maioria das regiões metropolitanas estão concentradas em zonas costeiras, ocasionando a liberação de uma grande quantidade de poluentes e ameaçando a sobrevivência de inúmeras espécies, como os peixes. Neste estudo, tentamos avaliar possíveis danos no DNA em um dos recursos pesqueiros mais consumidos pelas comunidades ribeirinhas nesta região, a tainha (Mugil curema). Metodologias de Ensaio Cometa (EC) e Teste do Micronúcleo (MN) foram utilizadas em populações desta espécie, provenientes de cinco estuários Pernambucanos (rios Goiana e Jaguaribe no litoral Norte), (rios Sirinhaém e Formoso no litoral Sul) e (rio Capibaribe na região metropolitana). Para fins de comparação, uma amostra controle foi coletada no estuário do Rio Una (local de preservação ambiental), litoral sul do estado de São Paulo. Nossos resultados mostram que o estuário mais afastado da região metropolitana, o Rio Formoso, quando comparado ao grupo controle, foi quem apresentou os menores níveis de danificação genômica (P >0,05). Já os demais estuários apresentaram níveis elevados de danificação quando comparados ao controle (P < 0,05). Em especial, o estuário do rio Capibaribe, localizado na capital Pernambucana, foi aquele que apresentou um dos maiores níveis de dano genômico (P = 0,0001). Tais dados caracterizam-no como o mais impactado entre os cinco avaliados. Estes dados também apontam para uma forte associação entre níveis elevados de danificação genômica (macro e microlesões no DNA) em locais próximos a grandes contingentes demográficos e industriais. Consequentemente, este cenário de impactação pode também estar afetando a comunidade biótica como um todo, incluindo as comunidades humanas ribeirinhas que tem este recurso como forma de subsistência. Estes resultados demonstram a efetividade do uso de metodologias de EC e MN como protocolos rápidos e precisos na avaliação de ecossistemas marinhos, principalmente em regiões fortemente impactadas pelas atividades antrópicas. / The loss of biological diversity may be a reflection of environmental degradation, especially in places with large demographic contingents. In northeastern Brazil, most metropolitan regions are concentrated in coastal areas, causing the release of large amounts of pollutants and threatening the survival of many species, such as fish. In this study, we attempt to assess possible damage to the DNA in one of the most consumed fish resources by coastal communities in this region, mullet (Mugil curema). Methodologies comet assay (EC) and micronucleus test (MN) were used in populations of this species, from five Pernambucanos estuaries (Goiana and Jaguaribe rivers in the northern coast), (Sirinhaém and Formoso rivers in the south coast) and (Capibariberiver in Metropolitan region). For comparison purposes, a control sample was collected in the estuary of the Una River (local environmental preservation), southern coast of São Paulo. Our results show that the far estuary in the metropolitan area, the Formoso River, when compared to the control group, was the one who had the lowest levels of genomic damage (P> 0.05). None of the other estuaries showed elevated levels of damage compared to the control (P <0.05). In particular, the estuary of the river Capibaribe, located in Pernambuco capital, was the one who presented one of the highest levels of genomic damage (P = 0.0001). These data characterize it as the most affected among the five evaluated. These data also point to a strong association between high levels of genomic damage (macro and micro-lesions in DNA) in locations near major demographic and industrial contingent. Consequently, this scenario impaction may also be affecting the biotic community as a whole, including the riparian human communities that have this feature as a means of subsistence. These results demonstrate the effectiveness of using EC and MN methodologies as fast and accurate protocols in evaluating marine ecosystems, particularly in regions heavily impacted by human activities.
48

Regional Fisheries Management Organizations: is power listening to Science? / Organizações Regionais para o Ordenamento Pesqueiro: o poder está ouvindo a ciência?

Leandra Regina Gonçalves 19 September 2016 (has links)
One of the biggest challenges in contemporary global environmental governance is the future of marine biodiversity. Over the years, increased fishing efforts in previously remote areas drove many fish stocks to scarcity. The Regional Fisheries Management Organizations (RFMOs) emerged to solve the international fishery crisis, on the assumption that they would provide a forum where Member States may agree and discuss binding rules for the conservation and management of fish stocks within its geographical area of responsibility. Although some agreements existed for more than 60 years, many authors agree that they have not been fully effective in promoting the maintenance and conservation of fish stocks. There are many reasons that might explain the lack of effectiveness, one of them being that science is not very often listened to in the political decision-making process. In this research, the influence of knowledge and science in shaping policy decisions will be observed and analyzed. Therefore, the use of the epistemic communities theory, that which forms part of the constructivist turn in international relations -- was used to answer the main question posed here: when does power listen to science? When it does, does it bring more effectiveness in terms of knowledge, input from epistemic communities, does it induce states to change their behavior, and do these influences lead to policies, which can credibly improve biomass? Using process tracing, through elite interviews, and with a systematic compilation and study of meeting reports from three RFMOs: the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR); the International Convention for the Conservation of Atlantic Tunas (ICCAT); and the Commission for the Conservation of Southern Bluefin Tuna (CCSBT), the final conclusion is that they may listen to science, but their strategy, allies, and the ways in which it occurs differ case-by-case. / Um dos maiores desafios na governança ambiental global contemporânea é o futuro dos ecossistemas e da biodiversidade marinha. Ao longo dos anos, o aumento do esforço de pesca nas áreas anteriormente remotas levou muitas populações de peixes à escassez. As Organizações Regionais para o Ordenamento Pesqueiro (OROPs) surgiram para resolver a crise internacional de pesca, através um fórum onde os Estados-Membros podem acordar e discutir regras vinculativas para a conservação e gestão dos recursos pesqueiros no âmbito da sua área geográfica de responsabilidade. Embora alguns acordos existam há mais de 60 anos, muitos pesquisadores concordam que os mesmos não têm sido totalmente eficazes para promover a manutenção e conservação dos recursos pesqueiros. Muitas razões podem explicar a falta de eficiência no manejo, uma delas é que, o aconselhamento cientifico não é muitas vezes considerado nas decisões políticas. Nesta pesquisa, a influência do conhecimento e da ciência na tomada de decisões políticas serão avaliadas. Para isso, a teoria das comunidades epistêmicas, que faz parte da veia construtivista em Relações Internacionais, foi usada para responder à principal questão colocada aqui: quando é que o poder ouviu a ciência? E isso trouxe mais eficiência em termos do conhecimento proveniente das comunidades epistêmicas induzir os Estados a mudarem seu comportamento e a influência levar a políticas que aumentem a biomassa dos estoques pesqueiros? Com o uso de process tracing, por meio de entrevistas com atores e uma compilação sistemática dos relatórios das reuniões anuais, as OROPS: CCAMLR, ICCAT e CCSBT foram estudadas, e a conclusão final é que, os tomadores de decisão podem ouvir a ciência, porém, a estratégia, os aliados e a forma como a influência se desenvolve varia caso a caso.
49

Políticas Públicas agroecológicas para comunidades quilombolas: um estudo de caso a partir do território / Public Policies for agroecological maroon communities: a case study from the territory

Silva, Rafael Jose Navas da 08 August 2014 (has links)
Com a Constituição Federal do Brasil de 1988, as comunidades remanescentes de quilombos adquiriram direito legal às áreas tradicionalmente ocupadas e o Estado passou a implementar Políticas Públicas visando seu desenvolvimento. Estas Políticas atualmente têm como foco a agroecologia, no sentido de manejo ecológico dos recursos naturais por meio de ação social coletiva. Porém, mesmo os projetos com tal enfoque não têm alcançado os resultados esperados, priorizando apenas a substituição de insumos sintéticos e práticas degradadoras. Considerou-se que o território pode ser um importante instrumento de análise de projetos de agroecologia e que projetos agroecológicos que abrangem as diferentes perspectivas do território têm maiores chances de resultados efetivos para comunidades quilombolas. Assim, o objetivo deste trabalho foi avaliar os Projetos Agroecológicos desenvolvidos na comunidade quilombola Mandira, em Cananéia/SP/Brasil. O trabalho foi realizado entre 2011 e 2014 através de técnicas qualitativas, com entrevistas, observação participante, história oral e análise de documentos. Os projetos analisados foram os relativos à criação da Reserva Extrativista do Mandira e manejo de recursos marinhos, e à implantação de sistemas agroflorestais. O projeto de manejo de recursos marinhos proporcionou inicialmente maior sustentabilidade à atividade e agregação de valor a partir da criação de uma Cooperativa, porém tem mostrado indícios de redução dos estoques naturais, segundo a percepção dos moradores, além da especialização na atividade e redução da produção para autoconsumo. O projeto de sistemas agroflorestais, de abrangência territorial, proporcionou maior diversidade de produtos, tanto para consumo quanto para comercialização, realizada em uma feira agroecológica. As famílias que trabalham com manejo de recursos marinhos possuem maior dependência do mercado, tanto para comercialização, quanto para obtenção de alimentos, diferentemente do outro projeto, que proporcionou maior autonomia, formação de capital social e alimentação saudável. Esses resultados podem confirmar a hipótese de que a perspectiva territorial se constitui um importante instrumento de avaliação de Projetos e também pode contribuir na implementação de ações de Políticas Públicas agroecológicas. / With the Federal Constitution of Brazil of 1988 the remaining maroon communities acquired statutory right to traditionally occupied areas and the Govern started to implement Public Policies aimed at their development. These policies currently are focused on agroecology, in the sense of ecological management of natural resources through collective social action. However, even projects with this approach have not achieved the expected results, just prioritizing the substitution of synthetic inputs and degrading practices. Whereas that the territorial approach involves endogenous and exogenous issues of the relationship between the community and the society, and would offer a greater opportunity of success in the implemented agroecological actions, the objective of this study was to evaluate Public Policies in Mandira maroon community in Cananéia, São Paulo State, Brazil, on these two different perspectives, agroecological and territorial. The study was conducted between 2011 and 2014 using qualitative techniques, including interviews, participant observation, oral history and document analysis. The analyzed projects were those concerning to the establishment of the Mandira Extractive Reserve and management of marine resources, and the implementation of agroforestry systems. The management project of marine resources initially provided greater sustainability to activity and adding value through the creation of a Cooperative, but it has shown signs of stock reduction, as perceived by residents, besides the specialization in the activity and reduction of production for self-consumption. The project of territorial coverage agroforestry systems, provided greater diversity of products, both for consumption and for sale, held in an agroecological fair. Families working with the marine resources management have greater dependence on the market, either for marketing as for obtaining food, unlike the other project, which provided greater autonomy, social capital formation and healthy eating, indicating that the territorial approach in Public Policy agroecological actions can contribute to more effective and sustainable results.
50

How to find the one that got away : predicting the distribution of temperate demersal fish from environmental variables

Chatfield, Brenton Sean January 2008 (has links)
Knowing where species are and understanding why is paramount for developing relevant and sustainable conservation and resource management strategies. The need for this information is becoming urgent as fishing activity, resource extraction and the impacts of coastal developments continue to put marine resources under increasing pressure. As logistical and financial constraints can restrict our ability to collect data in the marine environment, the ability to predict distributions based on known associations with different environmental variables would enhance our capacity to manage these resources. Before attempting to predict the distribution of species and groups of species, the underlying species-environment relationships must be examined to determine whether associations between species and the environment can: (i) be identified, (ii) be used to develop models that can accurately predict distributions, and (iii) are general enough to allow accurate predictions beyond the sampled area. Most studies to date have compared the composition of fish assemblages between sites to determine how different environmental variables influence distribution. While widely applied, these methods do not consider how individual species respond to multiple environmental gradients and they lack the ability to predict distributions across different combinations of variables along those gradients. This lack of prediction also limits our capacity to assess what marine biodiversity is presently threatened by global, regional, and local human pressures on marine ecosystems. '...' Thus, summarising and modelling species data at higher levels would result in models with poorer predictive accuracy and a loss of ecological information. The generality of the species-environment relationships defined by the models were assessed by evaluating the transferability of models between different areas. Models developed from data collected over a wider geographic extent could more accurately predict the distribution of species across a smaller spatial extent than vice versa. This indicated that while general theories of the ecology of temperate demersal fish can be defined, the actual patterns of distribution may vary from site to site, suggesting caution when using predictions beyond the sampled area for management purposes. Overall, species distribution modelling identified how different species and groups of species responded to the combined influence of multiple environmental gradients and was able to accurately predict distributions based on the defined associations. Their application has led to a greater understanding of the species environment relationships and will help to identify those areas that may be important for conservation. Their predictive ability will allow general predictions of distribution of fish species across unsurveyed areas and provides the ability to assess the potential impact from implementing different policy and management strategies.

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