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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.
691

Indicadores ambientais como instrumento de avaliação de reservas de desenvolvimento sustentável: estudo de caso do Mosaico de Unidades de Conservação Jureia Itatins (2002-2016) / Environmental indicators as an instrument for the evaluation of Sustainable Development Reserves: Case study of the Jureia Itatins Conservation Area Mosaic (2002-2016)

Beatriz Decarli Oliveira 20 April 2018 (has links)
Devido à importância da preservação da Mata Atlântica, à biodiversidade na região do Mosaico de Unidades de Conservação (MUC) Jureia Itatins e aos conflitos socioambientais presentes na região, torna-se necessário identificar e avaliar a real condição em que se encontram as comunidades humanas ali presentes, analisando as alterações causadas neste ambiente decorrentes da alteração antrópica, de modo a avaliar a implantação de Reserva de Desenvolvimento Sustentável (RDS) na região do MUC. Para tal, foi utilizada a metodologia de indicadores ambientais, selecionados e avaliados pelo método de Pressão Estado Impacto e Resposta (PEIR), determinando critérios de análise socioambiental e jurídica. Os dados foram levantados de forma primária e secundária, analisados com base nesses critérios, previamente definidos. Após essa análise, obteve-se um diagnóstico socioambiental da região. Com base no diagnóstico e nos critérios estabelecidos de enquadramento socioambiental e jurídico, conclui-se sobre a viabilidade da implantação de um MUC em Jureia Itatins, no que se refere à preservação da biodiversidade, à integridade dos ecossistemas ali existentes e ao bem-estar das populações tradicionais presentes na região / Due to the importance of the preservation of the Atlantic Forest, the intense biodiversity in the region of the Jureia Itatins Conservation Area Moisaic and to the socio-environmental conflicts present in the region, it is necessary to evaluate and identify a reality in which to find themselves as communities there present. Analyzing changes in the market, in accordance with the information published in Sustainable Development Reserves (RDS). Single paragraph, was used in the methodology of environmental indicators, selected and updated by the Pressure State Impact and Response Method (PSIR). Data were collected on a primary and secondary basis, analyzed based on predefined criteria. After this analysis, a socioenvironmental diagnosis of the region was obtained. Based on the diagnosis and the established criteria of socio-environmental and legal framework, it is concluded on a possible viability of the implantation of a MUC in Jureia Itains, with respect to the preservation of the biodiversity, the integrity of the existing ecosystems and the well-being of the populations present in the region
692

Utilização do carbono-13 como marcador na partição de fotoassimilados em figueira /

Silva, Andréa Carvalho da , 1981- January 2009 (has links)
Resumo: O trabalho teve como objetivo avaliar, a viabilidade da metodologia para avaliação da translocação e alocação de fotoassimilados, utilizando o isótopo estável do carbono-13 como marcador, assim como, avaliar a relação fonte-dreno nos diferentes órgãos bem como, saber em que órgão se encontraria o carbono-13 após determinados intervalos de tempo, em plantas em estádio reprodutivo da espécie Ficus carica L. Para tanto, uma folha da figueira considerada adulta através da caracterização fotossintética com um medidor portátil de fotossíntese IRGA-6400, foi colocada dentro de uma câmara de acrílico construída para este fim, e submetida a um ambiente com enriquecimento de 13CO2 por 30 minutos. Após 24 horas, os diferentes órgãos presentes nas plantas foram coletados no experimento órgãos drenos, nas demais plantas seguiu-se a experimentação tempo de alocação, onde as plantas de Ficus carica L. foram arrancadas ao longo das horas: 6, 24, 48, 72, 120, 168, 360. Após o tempo especificado as partes (meristema apical, folhas, ramos, caule e sistema radicular) das plantas em estudo foram coletados e imediatamente imersos em nitrogênio líquido (-196 ºC), para evitar que os tecidos permanecessem vivos e conseqüentemente pudessem consumir os fotoassimilados no processo da respiração. As amostras, previamente identificadas foram secas em estufa de circulação forçada a 65º C por 72 horas, em seguida moídas em moinho criogênico, para que houvesse uma perfeita homogeneização, sendo posteriormente analisadas no espectrômetro de massas de razão isotópica, para a determinação do enriquecimento relativo de 13C. Naturalmente a planta apresenta valores de enriquecimento relativo de 13C - 27,92‰, alocando acima de 90% da massa seca e do carbono total nas partes lenhosas. Os resultados obtidos indicaram que figueira se caracteriza como uma planta do ciclo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The work have planned be quizzed, the feasability of the methodology for evaluation of the fhotosynthates translocation and allocation, using the carbon 13 stable isotope a marker, evaluate the source-sink relation in the different organs and, know in that organ would be found the carbon-13 after determined time periods, in Ficus carica L. plants in reproductive stadium. A fig tree leaf considered adult through the photosynthetic with a portable meter of photosynthesis IRGA-6400 characterization. Was put inside a acrylic chamber, and submitted to an environment with 13CO2 enrichment for 30 minutes. After 24 hours, the different organs present in the plants were collected in the drains organs experiment, in the other plants followed the allocation time experimentation where the plants of Ficus carica L. were lurches to the long one of the hours: 6, 24, 48, 72, 120, 168, 360. After the time specified the studied plant parts (meristem, sheets, branches, stem and system roots) were collected and immediately immersed in liquid nitrogen (-196 ºC), for avoid that the fabrics remained alive and consequently could consume the fhotosynthates in the breath trial. The samples, previously identified were droughts in of circulation forced to 65º C for 72 hours, right away ground in cryogenic mill, for that had a perfect homogenization, being subsequently analyzed in the mass spectrometry of isotopic reason, for the relative enrichment... (Complete abstract click electronic access below) / Orientador: Sarita Leonel / Coorientador: Carlos Ducatti / Banca: João Domingos Rodrigues / Banca: Marco Antonio da Silva Vasconcellos / Mestre
693

Stories in the landscape : the sorry rock phenomenon and the cultural landscape of Uluru-Kata Tjuta National Park

Foxlee, Jasmine, University of Western Sydney, College of Arts, School of Social Sciences January 2008 (has links)
Each day the joint managers of Uluru-Kata Tjuta National Park receive packages of returned rocks and sand that have been removed from the landscape by visitors as a souvenir of the place. The returned objects are sent from people all over the world as the stories of this phenomenon travel well beyond the Park boundaries. Known within the Park as the ‘sorry rocks’, these returned objects and their accompanying letters of apology reflect the different ways in which people engage with the landscape and interpret their surrounds. In this research, the sorry rocks have been used as a medium for examining the complex relationships that exist between visitors, heritage management and interpretation particularly in cross-cultural settings that recognise Indigenous cultural heritage. THIS THESIS CAN BE VIEWED AT UWS LIBRARY FOR RESEARCH OR PRIVATE STUDY PURPOSES ONLY BY PRIOR ARRANGEMENT. / Doctor of Philosophy (PhD)
694

Small, no-take marine protected areas and wave exposure affect temperate, subtidal reef communities at Marmion Marine Park, Western Australia

Ryan, Kylie A. January 2008 (has links)
[Truncated abstract] The ecological effects of marine protected areas (MPAs) in temperate ecosystems are poorly understood relative to their tropical counterparts. The limited number of rigorous empirical studies supporting existing theoretical models, increasing public awareness of the importance of marine conservation strategies and legislative requirements to review management effectiveness provide further impetus to study temperate MPAs. Investigations should consider confounding effects of natural variability if MPA effects are to be clearly demonstrated. This research helps to address these needs by investigating the short term effects of sanctuary zones (no-take MPAs where fishing is prohibited) and wave exposure at Marmion Marine Park, Western Australia. The three sanctuary zones at Marmion Marine Park are extremely small (0.061 0.279 km2) compared to most reported in the literature. The sanctuary zones are nested within a larger, fished zone (94.95 km2). The sanctuary zones have been protected from fishing since the year 2000. A post-hoc, asymmetrical sampling design was used in this study and involved surveys of fishes, mobile invertebrates and macroalgae at one sanctuary zone and two fished sites (controls) at each of three successive, subtidal reef lines. The three reef lines are exposed to a gradient in wave energy. The size structure and abundance of the heavily exploited Panulirus cygnus (Western Rock Lobster) were positively affected by protection from fishing in sanctuary zones, despite the highly mobile nature of this migratory species. The mean abundance of legal size lobsters was higher in sanctuary zones compared to fished sites during an interannual study (2003, 2005 and 2006). The total abundance of lobsters and the mean abundance of legal size lobsters were higher at inshore and offshore sanctuary zones compared to fished control sites during a 2005/2006 fishing season study. These zoning effects did not vary with the time of survey. ... Furthermore, the abundance of large lobsters in sanctuary zones decreased with the duration of the 2005/2006 fishing season. Similarly, it is likely that sanctuary zones are too small relative to the movement of fishes to adequately protect stocks of some targeted species. The small sanctuary zones at Marmion are unlikely to offer protection to highly mobile species over the long term. And finally, ecological assemblages within each level of wave exposure are distinct. Consequently for each assemblage type, the current reserve design does not include replication of sanctuary zones and does not offer any 'insurance' in the event of isolated impacts affecting a particular zone. This study has identified the benefits and deficiencies of the design and function of small no-take temperate MPAs in Western Australia. An increase in the size and number of sanctuary zones within each wave exposure level will help to address the v shortfalls of the zoning scheme and enhance the conservation benefits of management at Marmion Marine Park. More generally, this study demonstrates that the mobility of the species to be protected from fishing should be considered when designing MPAs. Lessons learned from this work will be beneficial for the future management and conservation of resources in the region and elsewhere.
695

Mining in national parks : a case study--An integrated environmental evaluation of possible magnesite mining in Weetootla Gorge within the Gammon Ranges National Park, South Australia

Stoll, J. A. E. (Julie-Ann E.) January 1989 (has links) (PDF)
Bibliography: leaves 146-152.
696

Effects of man on the vegetation in the national parks of South Australia

Mattiske, Elizabeth M. January 1975 (has links) (PDF)
Volume 2 consists almost entirely of maps. Includes index of plant species. Bibliography: p. 227-242 (v.1) Floristic and structural changes in native vegetation resulting from man's influence are examined in detail in 5 South Australian parks. The results permit the clear delineation and segregation of those patterns determined by man's activities, from those induced by soil and topographic features.
697

The development and application of benthic classifications for coral reef ecosystems below 30 m depth using multibeam bathymetry : Tutuila, American Samoa

Lundblad, Emily Ruth 07 June 2004 (has links)
Coral reef ecosystems are the most diverse on earth, and their subsistence is being threatened by natural and adverse anthropogenic patterns and processes. In an effort to understand and protect these marine environments, several programs have outlined strategies and initiatives. For example, the United States Coral Reef Task Force���s Mapping and Information Working Group has outlined a specific goal to map all coral reefs below 30 m depth by 2009. This study contributes to achieving that goal for three sites around the island of Tutuila, American Samoa, lying in the heart of the South Pacific. American Samoa, a U.S. territory, is home to the Fagatele Bay National Marine Sanctuary, the smallest and most remote in the United States, and to the National Park of American Samoa. Extensive modern scientific surveys were implemented around the territory in 2001 and have since continued and increased. The presence of protected areas and the existence of scientific data collected with state of the art technology have made the site a priority for the Coral Reef Task Force. In this study, methods for classifying surficial seafloor characteristics as bathymetric position index (BPI) zones and structures were developed and applied to the study sites. BPI zones and structures were classified by using algorithms that combine high-resolution (1 m) multibeam bathymetry and its derivatives: bathymetric position index at multiple scales and slope. The development of algorithms and the classification scheme involved the use of historical and current classification studies and three-dimensional visualization. In addition, the BPI zones and structures were compared to limited biological, geological, and physical attributes recorded during accuracy assessment surveys (photos) and towed diver surveys (video). A rugosity (surface ratio) analysis was added to the study to give a picture of the seafloor roughness. The BPI zone and structure classifications overlap and extend existing classifications from Ikonos satellite imagery for water depths shallower than 30 m. Methods, data and classifications developed and applied in this study will be available to the public as a benthic habitat mapping tool (ArcGIS extension), in an online GIS data archive, and on a compact disc attached to this thesis. They contribute to a broader understanding of the marine and coastal environment and will serve as a baseline of information for benthic habitat mapping and future biological, ecological, and geological surveys. The baseline gives a good indication of characteristics that may indicate areas of high biodiversity. The final maps presented here are especially useful to managers, researchers and scientists that seek to establish and monitor a wider and more effective network of marine and coastal protection. / Graduation date: 2005
698

Det svenska områdesskyddet : Ett samspel mellan diskurs och institutioner

Farzin, Maziar January 2010 (has links)
Sweden has had laws protecting nature for about a hundred years. In this paper the views of nature and the values that serve as a rationale for protective measures are analyzed as results of a social process characterized by the dialectic relationship between institutions and discourse. Critical discourse analysis (CDA) is used to study this relationship and the discursive practices used by institutions, which reproduce or reshape views of nature that define the relationship between society and nature. Institutional design contributes to shaping discourse in the field of nature protection, while being originally shaped by discourse. In Sweden, the national park is an institution that reproduces a view of nature as the wild and untamed opposite of society, and the natural reserves reproduce a view of nature as holder of a multi-faceted set of values intertwined with society. However, the most recently formed national park, the marine national park of the Koster sea includes resource values that threaten the hegemony of arcadian discourse within the institution and indicates social change.
699

Nurturing resilience in social-ecological systems : Lessons learned from bridging organizations

Schultz, Lisen January 2009 (has links)
In an increasingly complex, rapidly changing world, the capacity to cope with, adapt to, and shape change is vital. This thesis investigates how natural resource management can be organized and practiced to nurture this capacity, referred to as resilience, in social-ecological systems. Based on case studies and large-N data sets from UNESCO Biosphere Reserves (BRs) and the UN Millennium Ecosystem Assessment (MA), it analyzes actors and social processes involved in adaptive co-management on the ground. Papers I & II use Kristianstads Vattenrike BR to analyze the roles of local stewards and bridging organizations. Here, local stewards, e.g. farmers and bird watchers, provide on-site management, detailed, long-term monitoring, and local ecological knowledge, build public support for ecosystem management, and hold unique links to specialized networks. A bridging organization strengthens their initiatives. Building and drawing on multi-level networks, it gathers different types of ecological knowledge, builds moral, political, legal and financial support from institutions and organizations, and identifies windows of opportunity for projects. Paper III synthesizes the MA community-based assessments and points to the importance of bridging organizations, leadership and vision, knowledge networks, institutions nested across scales, enabling policies, and high motivation among actors for adaptive co-management. Paper IV explores learning processes catalyzed by bridging organizations in BRs. 79 of the 148 BRs analyzed bridge local and scientific knowledge in efforts to conserve biodiversity and foster sustainable development, provide learning platforms, support knowledge generation (research, monitoring and experimentation), and frame information and education to target groups. Paper V tests the effects of participation and adaptive co-management in BRs. Local participation is positively linked to local support, successful integration of conservation and development, and effectiveness in achieving developmental goals. Participation of scientists is linked to effectiveness in achieving ‘conventional’ conservation goals and policy-makers enhance the integration of conservation and development. Adaptive co-management, found in 46 BRs, is positively linked to self-evaluated effectiveness in achieving developmental goals, but not at the expense of conservation. The thesis concludes that adaptive collaboration and learning processes can nurture resilience in social-ecological systems. Such processes often need to be catalyzed, supported and protected to survive. Therefore, bridging organizations are crucial in adaptive co-management.
700

Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geese

Traylor, Joshua James 02 July 2010
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p> Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p> I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p> Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.

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