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Právní režim Anktarktidy, zejména ochrana jejího životního prostředí a postavení České republiky / Legal regime of Antarctica with a special focus on the protection of the environment and the position of the Czech RepublicPřech, Ondřej January 2015 (has links)
The objective of the thesis is to describe the legal regime of the Antarctic specifically in relation to the protection of its environment. The introductory chapters are devoted to brief description of the natural conditions of the Antarctic and the history of its exploration. In relation with the discovery voyages there are also mentioned the first territorial claims of the states and the legal foundations on which these claims were made. The author also deals with the basic legal document in relation to this continent, the Antarctic Treaty, mainly with its main principles as the demilitarization, prohibition of appropriation and the recognition of previous claims. Under the Antarctic Treaty several categories of the Parties to the Treaty can be distinguished which is an un-common situation. The existence of the Antarctic Treaty Consultative Meeting which is related to this situation is also being discussed. This Consultative Meeting further develops the principles of the Antarctic Treaty and issues Measures, Decisions and Resolutions. This thesis focuses on the analysis of the protection of the environment of the Antarctic. The topic has been divided into separate components of the environment and these are dealt with in individual chapters of the thesis where the steady development and the introduction...
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Právní režim Antarktidy a ochrana jejího životního prostředí / The legal regime of Antarctica and the protection of its environmentLedl, Jakub January 2018 (has links)
The purpose of the diploma thesis is to describe and summarize the legal regime of Antarctica including its evolution, functioning and the protection of its environment. Chapter one of the thesis consists of the introduction with the Antarctic continent including the natural conditions, the history of the discovering, the competition between Roald Amundsen and Robert Falcon Scott to reach the South Pole and the territorial claims of seven states in the first half of the twentieth century. The second chapter deals with the fundamental document of the legal regime of Antarctica - The Antarctic Treaty. The Antarctic Treaty was signed in Washington on 1 December 1959 by the twelve countries whose scientists had been active in and around Antarctica during the International Geophysical Year of 1957-58. The very important provisions of the Treaty contain international cooperation and prohibition of any measures of a military nature, such as the establishment of military bases and fortifications, carrying out of the military maneuvers, as well as testing of any type of weapons. Antarctica became international space which can not be appropriated by individual states. The third chapter deals with the Antarctic Treaty System and its analysis and summary. The Antarctic Treaty System regulates the international...
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The Antarctic exception: sovereignty and the Antarctic Treaty governance / A exceção Antártica: soberania e a governança do Tratado AntárticoSampaio, Daniela Portella 19 April 2017 (has links)
This thesis discusses the undefined condition of sovereignty in Antarctica and its implications for the governance of the region. Antarctica emerged into international society with the expansion of its primary institutions in the nineteenth century. Sealing and whaling were the first practices and identities to develop, followed by exploration and scientific expeditions to the continent. Knowing and controlling the Antarctic region promised not only commercial supremacy at the beginning of the twentieth century, but also the reinforcement of national desires for imperial greatness. Sovereignty claims were stated by Argentina, Australia, Chile, France, New Zealand, Norway and the United Kingdom, but not mutually recognised. This conundrum established the foundation of Antarctic politics until the present day. Claimants have pursued to demonstrate authority in any way possible, and have been confronted not only by rivals\' overlapping claims but also by the Soviet Union and the United Sates, potential claimants who did not recognise sovereignty without effective occupation, but who did save their own rights to make claims in the future. The impossibility to reach a common agreement was solved by instituting a permanent non-solution: the Antarctic Treaty established a governance where claimants and potential claimants maintained control over decision-making. Its diplomatic culture constituted a social system which preserved the original power-configuration through consensus, slow institutional transformation and limited participation from other actors. As fields of activity that did not define sovereignty, scientific research and environmental protection were raised as Antarctic principles. They have legitimised the Treaty to international society, as peace has been maintained in the region. However, as the main decision-makers, claimants and potential claimants have reassured their leading roles by their scientific and environmental performance, as experience and expertise are seen to be indispensable qualities for those engaging in a region as exceptional as Antarctica. Since sovereignty and territoriality were not subject to norm localisation in the same way as that found in international society, Antarctica was defined as an exceptional place, demanding an exceptional governance framework for claimants and potential claimants as the ultimate authority in the region. By explicitly making sovereignty an undefined article, the Treaty configures a regional international society made exceptional in order to preserve its original authority. / Esta tese propõe discutir as implicações de uma soberania indefinida para a governança antártica. A Antártica emergiu na sociedade internacional por meio da expansão de suas instituições primárias para a região. Atividades foqueiras e baleeiras configuraram as primeiras práticas e identidades, seguidas por expedições científicas e de exploração. Conhecer e controlar esta região garantiam não só liderança comercial às nações envolvidas, mas também o fortalecimento de seus imaginários nacionais no início do século XX. Assim, soberania territorial foram reivindicadas por Argentina, Austrália, Chile, França, Nova Zelândia, Noruega e Reino Unido, porém sem mútuo reconhecimento. Este impasse passou, então, a fundamentar a política antártica. Os reclamantes buscaram demonstrar sua autoridade por diversas formas, uma vez que eram antagonizados não só por reivindicações rivais, mas também pela União Soviética e pelos Estados Unidos, potenciais reclamantes que não reconhecem soberania sem ocupação efetiva; mas que resguardam seus próprios direitos para uma futura reivindicação. A impossibilidade de se chegar a um acordo foi resolvida por meio da suspensão das discussões sobre soberania, o que na prática manteve o controle de reclamantes e potenciais reclamantes sobre a tomada de decisões. A cultura diplomática do Tratado Antártico constituiu um sistema social que preservou a configuração original de poder através do consenso, da lenta transformação institucional e da participação limitada de outros atores. Por outro lado, por não demandarem uma definição de soberania, pesquisa científica e proteção ambiental foram alçadas como princípios antárticos, legitimando perante a sociedade internacional um Tratado que vem assegurando a paz na região. Pesquisa científica e proteção ambiental também preservaram o protagonismo dos reivindicadores e potenciais reivindicadores no processo decisório, uma vez que experiência e expertise são considerados essenciais em uma região definida como excepcional. Dado que soberania e territorialidade não poderiam ter sua localização normativa de forma similar à sociedade internacional, a Antártica foi definida como um lugar excepcional, demandando um arranjo governamental particular onde reclamantes e potenciais reclamantes pudessem atuar como autoridade final na região. Uma soberania formalmente indefinida pelo Tratado configura uma sociedade internacional regional estruturada excepcionalmente, de maneira a preservar seu arranjo original de autoridade.
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Bioprospecção de leveduras da Antártica para a produção de biossurfactante a partir de hidrolisado hemicelulósico de palha de cana-de-açúcar / Bioprospecting of yeasts from Antarctica for the production of biosurfactant from hemicellulosic hydrolysate of sugarcane strawChaves, Flaviana da Silva 13 June 2017 (has links)
A produção comercial dos surfactantes ocorre principalmente por síntese química a partir do petróleo. A via biotecnológica se apresenta como uma alternativa promissora por possibilitar a utilização de biomassas vegetais, ricas em carboidratos a exemplo da palha de cana-de-açúcar. Assim, esta biomolécula torna-se mais competitiva comercialmente em relação aos surfactantes químicos, obtendo um processo biossustentável e biodegradável. Microrganismos isolados da Antártica apresentam potencial para a produção destas biomoléculas, uma vez que em condições extremas de sobrevivência estas poderiam ser produzidas em concentrações elevadas. Assim, este estudo avaliou a produção de biossurfactante em hidrolisado hemicelulósico de palha de cana-de-açúcar (HHPC) a partir de leveduras da Antártica, além da caracterização parcial da biomolécula e testes de estabilidade da emulsão. Inicialmente foram avaliadas 24 leveduras, cultivadas em frascos Erlenmeyer de 50 mL em meio semi-definido contendo xilose ou glicose como fontes de carbono, a 25ºC, 150 rpm, por até 72 horas. As propriedades emulsificante e tensoativa do bioproduto foram avaliadas e as culturas que apresentaram resultados satisfatórios para ambas as propriedades e consumo de xilose superior ou igual a 80% foram selecionadas para cultivo em meio formulado com HHPC. Das 24 leveduras testadas, três foram selecionadas para cultivo em hidrolisado: Cryptococcus laurentii (L62), Cryptococcus adeliensis (L95) e Rhodotorula mucilaginosa (L52). Destas, a levedura Cryptococcus adeliensis (L95) se destacou por apresentar produção de biomoléculas com maior propriedade emulsificante e tensoativa. Para esta levedura o consumo de xilose em meio semi-definido e em HHPC bem como o índice de emulsificação nas diferentes condições foram semelhantes. O biossurfactante produzido por Cryptococcus adeliensis (L95) foi caracterizado como glicolipídeo. Diferentes métodos de extração desta biomolécula foram testados, no entanto, estes não apresentaram diferença significativa. A estabilidade da emulsão obtida do sobrenadante de L95 em HHPC foi determinada em distintas condições físico-químicas, sendo que esta foi estável a pH extremamente baixo (2,00), baixas temperaturas (0oC e 4oC) e elevada concentração salina (10% m/V). Estes resultados são promissores considerando o potencial de aplicação de biossurfactantes em biorremediação bem como insumos nos mais diversos segmentos industriais, os quais necessitam de biomoléculas que resistam às mais diversas condições ambientais. Desta forma nesta pesquisa foi possível inferir que a biomassa de palha de cana pode ser destinada à obtenção de biossurfactantes a partir de leveduras da Antártica, destacando a relevância da pesquisa quanto à inovação biotecnológica. / The commercial production of surfactants occurs mainly by chemical synthesis from petroleum. The biotechnological pathway is considered as a promising alternative because it allows the use of vegetable biomass, rich in carbohydrates such as sugarcane straw. Thus, this biomolecule becomes more commercially competitive with respect to the chemical surfactants, obtaining a biodegradable process. Microorganisms isolated from Antarctica have the potential to produce these biomolecules, since under extreme conditions of survival, these could be produced in higher concentrations. In this way, this study aims to evaluate the biosurfactant production in sugarcane straw hemicellulosic hydrolysate from Antarctic yeasts, in addition to the partial characterization of the biomolecule and stability tests of the emulsion. Initially, 24 yeasts were evaluated, grown in 50 mL Erlenmeyer flasks in semi-defined medium with xylose or glucose as carbono sources, at 25ºC, 150 rpm, up to 72 hours. The emulsifying and surfactante properties of the bioproduct were evaluated, and the cultures that had satisfactory results for both properties and xylose consumption higher or equal to 80% were selected to be cultivated in a medium formulated with sugarcane straw hemicellulosic hydrolysate (SSHH). In the 24 yeasts tested, three were selected to be cultivated in the hydrolysed: Cryptococcus laurentii (L62), Cryptococcus adeliensis (L95) and Rhodotorula mucilaginosa (L52). Among these C. adeliensis (L95) was distinguished by the production of biomolecules with higher emulsifying and tensoactive properties. For this yeast, the xylose consumption in semi-defined medium and in SSHH, as well as the emulsification index under diferente conditions were similar. The biosurfactant produced by C. adeliensis (L95) was characterized as glycolipid. Different methods of extraction of this biomolecule were tested, however, these did not have significant difference. The emulsion stability obtained from the C. adeliensis (L95) supernatant in SSHH was determined under different physicochemical conditions, which was stable at extremely low pH (2,00), low temperatures (0oC and 4oC) and high saline concentration (10% m/v). These results are interesting considering the potential of the biosurfactants application in bioremediation and inputs for several industrial segments, which require biomolecules that resist to the most diverse environmental conditions. In this research, it was concluded that sugarcane straw biomass can be used to obtain biosurfactants from Antarctic yeasts, consequently highlighting the research relevance regarding to the biotechnological innovation.
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"Avaliação de introdução de esteróis fecais e hidrocarbonetos marcadores geoquímicos em sedimentos da Baía do Almirantado, Península Antártica" / Evaluation of fecal sterols and geochemical markers hydrocarbons in sediments from Admiralty Bay, Antartica.Martins, César de Castro 01 February 2002 (has links)
Esgoto e hidrocarbonetos provenientes de atividades humanas são as principais fontes de poluição para o meio ambiente marinho antártico. Esteróis e hidrocarbonetos como n-alcanos, policíclicos aromáticos (PAHs) e alquilbenzenos lineares (LABs) foram investigados em sedimentos superficiais coletados na Baía do Almirantado, Antártica durante o verão de 1997/1998 e 1999/2000. Estes compostos são citados como traçadores de dejetos humanos e introdução de óleos ao longo de áreas costeiras de todo o mundo. As técnicas analíticas utilizadas foram a cromatografia a gás com detector de ionização de chama (GC-FID) e espectrômetro de massa (GC-MS). Análises de esteróis indicaram que o esgoto atinge até 700 metros desde a saída de efluentes, mas somente o ponto de descarga pode ser considerado poluído. Dados de LABs concordaram com os resultados obtidos para os esteróis indicando que dejetos humanos chegam até 1 Km desde a estação brasileira e que esteróis encontrados em pontos distantes são provenientes de fontes naturais. Os níveis obtidos para n-alcanos e PAHs foram similares àqueles obtidos em outros estudos envolvendo regiões antárticas. Contribuições biogênicas e pequenas introduções antropogênicas são as fontes dos n-alcanos detectados. PAHs encontrados em pontos distantes são associados como pequena contribuição de óleos enquanto que amostras coletadas na saída de esgoto e até 50 metros apresentam PAHs de origem pirolítica ou de esgotos. Este estudo concluiu que apenas a saída de efluentes pode ser considerada ponto altamente poluído e verificou a presença de uma substancial diminuição do aporte de esgoto com o aumento da distância desde a fonte. / Sewage and oil contribution are the main sources of pollution from the scientific stations to the antarctic marine environment. Sterols and hydrocarbons such as n-alkanes, polyciclic aromatics (PAHs) and linear alkylbenzenes (LABs) were investigated on surface sediments from Admiralty Bay, King George Island, Antarctica, collected during austral summer of 1997/1998 and 1999/2000 It has been previously used as a tracer from human waste and oil inputs along the coastal areas around the world. The analytical techniques used were gas chromatography with flame ionization detection (GC-FID) or attached with a mass spectrometer (GC-MS). Analyses of sterols showed that sewage moves until 700 meters since sewer outfall, but only the discharge point can be considered polluted. Data from LABs agreed with sterols results indicating that human wastes arrive until 1 Km from brazilian station and sterols found in remote areas were from natural contributions. N-alkanes and PAHs showed the same levels than previous studies from pristine areas in antarctic continent. Biogenic and little antropogenic sources are the origins from n-alkanes. PAHs found in distant points are associated with small oil contribution while samples collected in sewer outfall and until 50 meters far presented PAHs from combustion process and sewage. This study concluded that only the sewage discharge point is very polluted however there is a substantial sewage input decrease with the increase of distance from outfall.
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Atividade lipolítica e biodiversidade de fungos filamentosos derivados da Antártica. / Lipase activity and biodiversity of filamentous fungi derived from Antarctica.Nobre, Fernando Suzigan 26 March 2013 (has links)
Lipases ativas em temperaturas frias estão amplamente distribuídas em micro-organismos que sobrevivem em temperaturas baixas, neste contexto, o isolamento de fungos de ambiente antártico pode ser considerado estratégico para obtenção de lipases a baixas temperaturas. O presente trabalho teve como objetivo avaliar a produção de lipases e a diversidade de fungos filamentosos isolados de amostras do ambiente Antártico. Um total de 253 isolados foi recuperado a partir de 10 amostras marinhas e quatro terrestres, dos quais 68 apresentaram resultados positivo e foram submetidos aos experimentos de avaliação da produção de lipase e caracterização da biodiversidade. Os fungos lipolíticos foram identificados como pertencentes aos gêneros: Geomyces, Penicillium, Cosmospora, Thelebolus, Chaetomium, Hypocrea, Antarctomyces, Mortierella e Cadophora. Em adição, alguns isolados de um mesmo ribotipo foram afiliados à ordem Mucorales e, outro, revelou ser uma potencial nova espécie pertencente ao filo Basidiomycota. O fungo Geomyces pannorum. AL1-1B foi selecionado como o melhor produtor de lipase e apresentou atividade de 761,68 U/L no 5° dia de cultivo em pH 8,0 a 15 °C, evidenciando o potencial biotecnológico na produção de lipase a baixas temperaturas. / Cold-active lipases are widely distributed in micro-organisms which survive in low temperatures, in this context; fungal isolation from Antarctic environment can be considered strategic for obtaining lipases at low temperatures. The present work aimed to assess the production of lipases and diversity of filamentous fungi isolated from samples of the Antarctic environment. A total of 253 isolates were retrieved from 10 marine and four terrestrial samples collected on the Antarctic continent, amongst then 68 presented positive results and were subjected to the experiments of lipase production evaluation and biodiversity characterization. Lipolytic fungi were identified as representatives of the genera: Geomyces, Penicillium, Cosmospora, Thelebolus, Chaetomium, Hypocrea, Antarctomyces, Mortierella and Cadophora. In addition, some isolates of the same ribotype were affiliated to the order Mucorales, and another one, showed to be a putative new species from phylum Basidiomycota. The fungus Geomyces pannorum AL1-1B was selected as the lipase best producer and showed activity of 761.68 U/L in the 5th day of cultivation at pH 8.0 at 15 °C, highlighting the biotechnological potential for lipase production at low temperatures.
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Além da Antártica: os limites da vida ao frio e à dessecação no âmbito da astrobiologia. / Beyond Antarctica: the limits of life to cold and desiccation in the context of astrobiology.Pereira, Felipe Nóbrega 05 February 2016 (has links)
Na Antártica e no Ártico, a vida microbiana é presente e diversificada, tendo se adaptado a condições similares às encontradas em mundos que despertam interesse à astrobiologia. Este estudo investigou as alterações fisiológicas e fenotípicas do extremófilo psicrotrófico Exiguobacterium antarcticum B7 sob diferentes temperaturas. Foram utilizadas técnicas de eletroforese de proteínas em duas dimensões associada a espectrometria de massa, juntamente com técnicas de microscopia. E. antarcticum foi também submetida a condições físicas encontradas em Marte e no ambiente interplanetário. Seguindo evidências de que micro-organismos psicrotróficos podem também ser resistentes a períodos prolongados de dessecação, foi investigada a presença de linhagens microbianas resistentes a anidrobiose em solos da Antártica e permafrost do Ártico. Por fim, voltando-se à ecologia microbiana de solos polares permanentemente congelados, foi estudada a diversidade microbiana de três estratos de permafrost do ártico canadense com o uso de sequenciamento de DNA de nova geração. / In Antarctica and the Arctic, microbial life is present and diverse, having adapted to low temperature and low humidity conditions, similar to the worlds that arouse more interest to astrobiology. This study investigated the physiological changes of the psychrotrophic extremophile Exiguobacterium antarcticum B7 at different temperatures. Two dimensional protein electrophoresis techniques was used for proteome analysis in conjunction with mass spectrometry, as well as microscopy techniques. E. antarcticum was also subjected to physical parameters found on Mars and in the interplanetary environment. Following evidence that psychrotrophic microorganisms may also be resistant to prolonged periods of desiccation, it was investigated the presence of microbial strains resistant to anhydrobiosis on Antarctic soils and Arctic permafrost. At last, turning the attention to the microbial ecology of permanently frozen polar soils, it was studied the bacterial diversity of three Arctic permafrost strata with next-generation high throughput DNA sequencing.
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An assessment of heterogeneity within the lithospheric mantle, Marie Byrd Land, West AntarcticaCohen, Shaina Marie January 2016 (has links)
Thesis advisor: Seth C. Kruckenberg / The West Antarctic rift system is one of the most expansive regions of extended continental crust on Earth, but relatively little is known about the structure of the mantle lithosphere in this region. This research aims to examine a suite of ultramafic mantle xenoliths from several volcanic centers located throughout Marie Byrd Land, West Antarctica. Through the use of several complementary analytical methods, the deformational and compositional heterogeneity of the lithospheric mantle in this region is characterized. The Marie Byrd Land xenoliths have equilibration temperatures between 779 and 1198°C, which is a range that corresponds to extraction depths between 39 and 72 km. These samples preserve significant mineralogical and microstructural heterogeneities that document both lateral and vertical heterogeneities within the Marie Byrd Land mantle lithosphere. The modal mineralogy of spinel peridotites varies between 40 – 99% olivine, 0 – 42% diopside, 0 – 45% enstatite and 0 – 5% chromite. Minimum olivine grain sizes range from 60 to 110 µm and maximum olivine grain sizes range from 2.5 to 10.0 mm. The geometric mean grain size of olivine in these samples ranges from 100 µm to 2 mm and has an average of 694 µm. The geometric mean grain size of diopside ranges from 90 to 865 µm and has an average of 325 µm, whereas that of enstatite ranges from 120 µm to 1.2 mm and has an average of 625 µm. Comparatively, the pyroxenites contain 0 – 29% olivine, 29 – 95% diopside, 1 – 36% enstatite and 1 – 11% chromite. Deformation mechanism maps suggest that the olivine within the MBL peridotite xenoliths primarily accommodate strain through the operation of dislocation-accommodated grain-boundary sliding at strain rates between 10-19/s and 10-11/s. This is consistent with microstructural observations of the suite made using optical microscopy (e.g., deformation bands and subgrains in olivine; aligned grain boundaries between contrasting phases). Application of the olivine grain size piezometer indicates that the suite preserves differential stresses ranging from 0.5 MPa to 50 MPa, with mean differential stresses ranging from 4 to 30 MPa. Values of mean differential stress only vary slightly throughout the field area, but generally decrease in magnitude towards the east with maximum values migrating upwards in the lithospheric mantle along this transect. The samples from some volcanic centers are highly homogenous with respect to their microstructural characteristics (e.g., Mount Avers – Bird Bluff), whereas others display heterogeneities on the sub-five-kilometer-scale (e.g., Demas Bluff). Comparatively, mineralogical heterogeneities are more consistent throughout the sample suite with variations generally being observed between the sub-five-kilometer-scale and the sub-ten-kilometer-scale. Most samples within the MBL peridotite suite display axial-[010] or A-type olivine textures. Although less dominant, axial-[100], B-type and random olivine textures are also documented within the suite. Axial-[010] textures have J-indices and M-indices ranging from 1.7 – 4.1 and 0.08 – 0.21, respectively. The average value of the J-index for axial-[010] textures is 2.9, whereas the average M-index of these samples is equal to 0.15. Overall, A-type textures tend to be stronger with J- and M-indices ranging from 1.4 – 9.0 and 0.07 – 0.37, respectively. The olivine crystallographic textures of the MBL xenolith suite are heterogeneous on scales that are smaller than the highest resolution that is attainable using contemporary geophysical methods, which implies that patterns of mantle flow and deformation are far more complex than these studies suggest. / Thesis (MS) — Boston College, 2016. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.
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A meiofauna e os Nematoda da enseada Martel (Antártica) e seu uso em monitoramento ambiental / Meiofauna and nematodes from Martel inlet (Antarctica) and their use in environmental monitoringGheller, Paula Foltran 31 August 2007 (has links)
O objetivo deste estudo foi avaliar se a estrutura da comunidade da meiofauna, das famílias e dos gêneros de Nematoda apresentam alterações devido à atividade antrópica na área próxima a Estação Antártica Brasileira (CF), em comparação com um controle (BP). A densidade média (ind.10cm-²) da meiofauna total variou entre 7028 (? 1529) e 16245 (? 12282) nos 20-30 m e entre 1569 (? 928) e 7088 (? 10338) nos 50-60 m, corroborando os valores altos já descritos para a zona rasa antártica. Nematoda foi dominante (>90%), seguido de Nauplii e Copepoda. 65 gêneros e 3 subfamílias de Nematoda foram encontrados, pertencentes a 24 famílias. Daptonema, Halailamus, Dichromadora, Sabatieria, Aponema e Sphaerolaimus foram dominantes nas duas profundidades, mas tiveram densidades mais altas nos 20-30 m relacionadas à maior biomassa de clorofila a. Não foram identificadas alterações na estrutura da comunidade da meiofauna, das famílias ou gêneros de Nematoda que pudessem ter sido causados por impacto antrópico. Porém, a riqueza e a diversidade das famílias e dos gêneros de Nematoda foram menores em CF, o que sugere um possível impacto, sendo importante a continuidade do monitoramento e a inclusão de outras áreas de referência. O nível taxonômico de família foi o mais apropriado para um estudo de monitoramento da zona costeira rasa antártica, visando o melhor custo-benefício. / The aim of this study was to verify if meiofauna, Nematoda family and genera community structure show modification caused by human activities at the Brazilian Antarctic Station (CF), in relation to a reference area (BP). Mean meiofauna densities ( ind.10 cm-²) ranged from 7028 (? 1529) to 16245 (? 12282) at 20-30 m and from 1569 (? 928) and 7088 (? 10338) at 50-60 m, being high as already described for the Antarctic coastal zone. Higher densities at 20-30m were correlated to more chlorophyll a and sand. Nematoda were dominant (>90%) followed by Nauplii and Copepoda. 65 genera and 3 subfamilies of Nematoda were found, belonging to 24 families. Daptonema, Halailamus, Dichromadora, Sabatieria, Aponema and Sphaerolaimus were dominant at both depths, but had higher densities at 20-30 m, which were correlated to higher chlorophyll a biomasses. Analysis for all levels of taxonomic resolution, separated the samples between depths, but not between areas, so differences caused by human impact were not detected. Number of genera ranged from 12 to 34 and diversity from 1.57 to 4.22 bits/ind, both being higher at 50-60m at BP, suggesting that an impact might have occurred, so monitoring should continue and be extended to other control areas. Identification of Nematoda to family level would be enough to evaluate environmental impact of the coastal antarctic zone.
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Estudo do vírus Influenza em aves marinhas na região subantártica. / Study of Influenza vírus in seabirds of subantarctica region.Seixas, Marina Maria Moraes de 07 October 2014 (has links)
Os vírus da influenza A (IA) provocam epidemias e pandemias em humanos. As aves selvagens são os reservatórios naturais desses vírus, dentre essas, as migratórias possuem um importante papel como transmissores da doença. A região subantártica abriga populações de aves marinhas, as quais reproduzem-se no verão austral formando colônias com milhares de aves, o que potencializa a importância do estudo do vírus IA em aves marinhas neste ambiente. Os objetivos deste trabalho foram analisar a presença do vírus IA em swabs orotraqueal e cloacal, e de anticorpos anti-IA em soro de aves marinhas da região subantártica, caracterizar molecularmente as amostras positivas, e conhecer mais a ecologia deste vírus. Foram coletadas amostras biológicas de pinguim-papua, pinguim-de-barbicha, pinguim-de-adelie, skua-subantártica, pomba-do-cabo, e petrel-gigante-do-sul, entre 2010-13, nas ilhas Elefante e Rei George. Das 615 amostras de swab, 13 foram positivas por One Step Real Time RT-PCR, e uma foi caracterizada como H6N8. Das 673 amostras de soro, 108 foram positivas por Ensaio Imonoenzimático competitivo (cELISA). O estudo contribuiu para o conhecimento do vírus IA na região e foram feitas recomendações para a prevenção a introdução de patógenos na Antártica. / Influenza A (IA) viruses cause epidemics and pandemics in humans. Wild birds are the natural reservoir of these viruses, among these, migratory ones have an important role as transmitters of disease. The subantarctic region is home to seabird populations, which breed in the austral summer forming colonies with thousands of birds, which enhances the importance of the study of AI viruses in waterfowl in this environment. The objectives of this study were to analyze the presence of IA virus in tracheal and cloacal swabs, and anti-IA antibodies in serum of seabirds from subantarctic region, molecular characterization of positive samples, and learn more about this virus ecology. Biological samples were collected of gentoo penguin, chinstrap penguin, adelie penguin, brown skua, cape petrel, and southern giant petrel, from Elephant and King George islands, between 2010-13.Of the 615 swab samples, 13 were positive by Real Time One Step RT-PCR, and one was characterized as H6N8. Of the 673 serum samples, 108 were positive by competitive enzyme-linked immunosorbent assay (cELISA). The study contributed to AI virus knowledge in the region and recommendations for preventing the introduction of pathogens in Antarctica were made.
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