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Industrial pollution control and management in Ethiopia : a case study on Almeda textile factory and Sheba leather industry in Tigrai Regional StateGhebretekle, Tsegai B. January 2015 (has links)
As a new emerging industrializing nation, industrial pollution is a challenge in Ethiopia. To address the problem, the government has introduced different laws, policies, strategies and established environmental organizations at federal and regional levels. However, the government has not performed well in this regard due to various barriers militating against sustainable industrial pollution control and management. Partly this is due to organizational weaknesses, lack of effective implementation of standards as well as the absence of expertise and capacity building. The aim of this research is to investigate the practice of industrial pollution control and management in Ethiopia with particular emphasis on two selected industries. For the practical investigation a methodology that combines semi-structured interview from key informants in industrial pollution, together with documentary and observational data has been employed. The findings of the research show that the magnitude of industrial pollution is rapidly increasing in the country. This is particularly the case in the textile and leather industries. It is also more severe in urban centers where most of the industries are located. The problem is most operating industries in Ethiopia do not have waste treatment plants. They simply discharge their untreated effluent to the nearby rivers or drainage facilities in violation of the established standards. Even for those industries with treatment plants (including the two case study industries) the treatment plants are not functioning properly due to cost implications; and they discharge their effluent to the nearby rivers with nominal treatment. Thus, they are sources of damage to the environment and the nearby communities. The main barrier to industrial pollution control has been the application of weak form of sustainable development policy and lack of institutional regulations—including laws and organizational implementing mechanisms. This is manifested through lack of political will on the part of the government to enforce the existing industrial pollution control laws; lack of capacity (resource and personnel) and coordination among the environmental organizations. On the part of the affected community there is lack of awareness and organization to protect their constitutionally enshrined right—the right to clean and healthy environment. Similarly there is also lack of corporate social responsibility on the side of the two industries subject of the study.
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Efecto del tamaño de los claros de dosel sobre variables microclimáticas en un bosque de Nothofagus antarctica (G. Forst.) Oerst. en la Región de AysénAravena Torres, Cristina Elena January 2018 (has links)
Memoria para optar al Título Profesional de Ingeniera Forestal / Se estudió la variación microclimática causada por los claros de dosel, separados según su tamaño en grandes, medianos y pequeños, en un bosque de N. antarctica ubicado cercano a la localidad de Balmaceda, Región de Aysén del General Carlos Ibáñez del Campo. Mediante el uso de fotografías hemisféricas, se estimó el porcentaje de radiación solar (RS) que llega al piso del bosque o del claro, respecto a la que estaría llegando sobre el dosel arbóreo. Además, se instalaron registradores de datos en los centros de los claros de dosel y bajo tres condiciones de cobertura continua de copas, que almacenaban la información de variables microclimáticas de manera continua de: temperatura del aire (TA, °C), temperatura del suelo (TS, °C) y contenido volumétrico de agua en el suelo (Ɵ, m3/m3), las que fueron compiladas a lo largo de un año. La RS directa, difusa y global transmitida muestra diferencias significativas entre los claros de dosel y la situación testigo, resultando siempre mayor en el claro de dosel grande, donde los montos de radiación fueron hasta casi 5 veces más alta de la que se registra bajo el bosque testigo. Respecto a TA y TS, las temperaturas mínimas y medias fueron más altas bajo el dosel arbóreo continuo durante los meses de otoño – invierno, con diferencias de hasta 0,7 ºC, mientras que las temperaturas máximas y medias más altas se registraron en el claro grande para los meses de primavera – verano con diferencias de hasta 3,9 ºC. En cuanto a Ɵ, los valores son más altos en los claros de dosel grande en el periodo de receso, y en el claro pequeño para el periodo de crecimiento, sin existir diferencias significativas entre sectores.
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Etude du formaldéhyde (HCHO) en zone côtière Antarctique / Study of formaldehyde in coastal Antarctica.Pépy, Guillaume 23 November 2011 (has links)
Avec pour objectif de documenter et comprendre ses sources et puits en atmosphère de fond, nous avons réalisé un enregistrement annuel du formaldéhyde troposphérique en Antarctique, sur la base côtière de Dumont d'Urville. Des teneurs mensuelles de 50 pptv en hiver jusqu'à 200 pptv en été ont été mesurées. Au printemps, et été et à l'automne, un cycle journalier a été observé, avec un maximum l'après midi et une amplitude d'environ 40 pptv. Les artéfacts observés avec les appareils utilisés pour la mesure de HCHO (AeroLaser 4021), liés aux variations de température dans le local de mesure et pouvant induire des biais de 50 à 100 pptv, ont été éliminés en adaptant notre méthode analytique. Le formaldéhyde étant produit lors des combustions, l'influence des sources de contamination locales a été examinée en détail. Les sources de combustion par la station augmentent sporadiquement de 150 pptv au maximum les moyennes horaires. Une source locale d'émission par les sols ornithogéniques en liaison avec la présence des Manchots Adélie peut influencer jusqu'à 200 pptv les moyennes horaires en été. Au total, ces deux sources locales peuvent surestimer d'un facteur 5 au maximum l'amplitude du cycle journalier observé et impacter jusqu'à 100 pptv les moyennes mensuelles en été. Suivant ce constat, les données brutes ont été filtrées selon des critères météorologiques locaux pour éliminer toute contamination potentielle. L'étude des sources et puits en phase gaz a été réalisée à l'aide d'un modèle de photochimie développé pour les conditions de DDU. Nos résultats montrent que l'oxydation du méthane domine le budget en été (80%) du fait des fortes teneurs en radicaux HOx et en NOx en liaison avec l'impact du plateau Antarctique atteignant DDU. Le méthyl-hydroperoxyde constitue une source secondaire significative de HCHO en phase gaz (20% de l'oxydation du méthane), tandis que les faibles teneurs en hydrocarbures non-méthaniques mesurées en été nous amène à évaluer la contribution de cette source initialement attendue comme importante à moins de 5% de l'oxydation de CH4. A la différence d'autres observations en Mer de Weddell, les composés halogénés semblent avoir une influence relativement limitée dans le cas de Dumont d'Urville (10% du budget total au maximum). Suivant nos estimations, l'apport continental efficace permet d'envisager une source d'émission par le manteau neigeux du plateau. Celle-ci constitue une source secondaire relativement faible en été (10%) mais domine le budget hivernal (70%). Notre exercice de modélisation sur l'échelle saisonnière et journalière souligne la nécessité d'associer les processus en phase gaz avec les flux d'émission par la neige et de dépôt afin de reproduire correctement les observations. / With the aim to investigate the production and destruction mechanisms of formaldehyde (HCHO) on a seasonal scale in the remote troposphere, HCHO was monitored over a 13-months period at Dumont d'Urville station, located near the East Coast of the Antarctic continent. Monthly means of 50 ppt in winter and up to 200 ppt in summer were measured. In spring, summer and autumn, a daily variation was detected with amplitude of ≈40 ppt and a maximum during the afternoon. The analytical instrument (Aerolaser, AL4021) deployed for the measurements, was found to be extremely sensitive to ambient temperature variations. The origin of the temperature dependence was investigated, and the deployed analytical method was adapted to eliminate this artefact. The impact of local contamination sources at the measurement site was explored in detail. Anthropogenic combustions were found to have a limited impact (maximum 150 pptv on hourly means) versus a local emission source from ornithogenic soils, induced by the omni-presence of Adelie penguins on the site in summer (maximum 200 pptv on hourly means). From november to march, these sources can introduce an overestimation by a factor 5 of the daily HCHO amplitude, while the influence on the monthly averaged budget can account up to 100 ppt. The raw dataset was thoroughly filtered using local meteorological criteria to eliminate any potential contamination. HCHO measurements were compared to simulations made with a numerical box model developed on the base of the current understanding of the photochemical sources and sinks of HCHO. During summer, methane oxidation was found to be the major source of HCHO production, likely due to enhanced levels of oxidants such as hydroxyl radical (OH) or nitrogen oxide (NO) occurring at DDU since this coastal site is under strong continental influence. Snow emissions and HCHO formation via methyl-hydroperoxyde oxidation complete the summer budget (respectively 10 to 20% of the CH4 oxidation). In contrary to what was observed for the Weddell Sea area, halogens chemistry is probably unlikely to contribute significantly at Dumont d'Urville (<10% of the CH4 oxidation). Finally, the initially attended summer source originating from non-methane hydrocarbons oxidation was found to be inefficient and to contribute only with less than 5 % of the CH4 oxidation. During winter the snowpack source was found to be preponderant (70% of CH4 oxidation) versus the gas phase chemistry sources of HCHO. Model investigations, performed on a seasonal and daily scale have shown that gas phase processes together with deposition and snow emission have to be considered to achieve a correct reconstruction of the observations.
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Avaliação do desempenho do modelo BRAMS para a Península Antártica / Performance evaluation of BRAMS model for the Antarctic PeninsulaMartins, Tatiane Reis 30 July 2012 (has links)
A Península Antártica (PA) é uma das regiões no planeta que apresentam as mais adversas condições do tempo devido à constante passagem de ciclones. O conhecimento das condições meteorológicas futuras é fundamental para o desenvolvimento de atividades operacionais e de pesquisa na região. Nos últimos anos a implantação e melhoramento dos modelos numéricos, que tem como foco a previsão do tempo na Antártica, têm sido alvo de diversos estudos pela comunidade acadêmica. O objetivo principal deste trabalho foi avaliar o desempenho do modelo BRAMS na simulação de parâmetros meteorológicos durante a passagem de ciclones na Península Antártica. Diversas simulações, que envolveram diferentes configurações estruturais e físicas do modelo foram realizadas para dois casos de passagem de ciclones na PA, um que ocorreu em fevereiro e outro em julho de 2009. A avaliação do desempenho do modelo BRAMS foi feita através de duas análises, uma qualitativa, analisado o comportamento de cada variável simulada pelo modelo em comparação com os dados de estações meteorológicas, e a outra uma análise de sensibilidade baseada em índices estatísticos. O desempenho do modelo BRAMS se mostrou altamente dependente das condições iniciais adotadas. A pressão ao nível médio do mar foi a variável melhor representada, mas o modelo não conseguiu prever adequadamente os aumentos de pressão que ocorrem após a passagem do ciclone pela PA, o que ficou evidente no evento de julho. Por outro lado, o BRAMS se mostrou ineficiente em representar as variações de temperatura que ocorrem durante o período de simulação, principalmente no evento de fevereiro. As temperaturas simuladas pelo BRAMS foram mais elevadas que aquelas observadas nas estações meteorológicas para os dois casos (fevereiro e julho). Além disso, o modelo não conseguiu prever as quedas abruptas de temperatura, observadas durante o avanço do ciclone no mês de julho, devido em grande parte à ausência de gelo marinho nas regiões onde, de fato, as observações mostravam que ele estava presente. O modelo BRAMS, de forma geral, não obteve bom desempenho na simulação do vento, principalmente em relação às variações de direção. O modelo capta as principais variações da componente zonal do vento no caso de verão, porém em algumas estações, quando o escoamento tornou-se meridional, o BRAMS simulou um vento de leste, demonstrando uma forte dependência das condições iniciais. Já no caso de inverno, após o ciclone cruzar a PA, os experimentos simulam um vento de oeste que não condiz com o observado nas estações meteorológicas. Já em se tratando do vento meridional notou-se que o BRAMS intensifica os fluxos de sul, principalmente após a passagem do ciclone pela PA. / The Antarctic Peninsula is one of the regions of the earth, which have the most adverse weather conditions due to the constant movement of cyclones. The knowledge of future meteorological conditions is essential for the operational activities and research developments on the region. In the last years, implantation and improvement of the numeric models, which focus is the weather forecasting on Antarctic, has been the subject of several studies of academic community. The main objective of this study is evaluating the model BRAMS performance, on the simulation of meteorological parameters in events of cyclones on Antarctic Peninsula. Several simulations with different structural and physics configurations on the model were performed in two events of cyclones on AP. One of them occurred in February e the other one in July of 2009. The evaluation of BRAMS model was performed by means of two analyses. The first analysis was qualitative, which analyzed the behavior of each variable simulated by the model in compared to weather stations data. The second analysis was related with the sensibility based on statistical indexes. The BRAMS model performance seems to be dependent on the initial conditions. The pressure at mean sea level was a well represented variable, however the model did not forecasted properly the pressure increase, which occurred after the cyclone event on the AP and it was more evident on event of July. Otherwise, the BRAMS seems to be inefficient for variations on temperatures during the simulation period, especially on February event. Temperatures simulated by BRAMS were higher than that observed on weather station for both cases (February and July). Furthermore, the model did not predicted the abrupt decrease in temperature, observed during the cyclone in July, due to the absence of ice sea in regions where, in fact, the observations showed that he was present. In general, the BRAMS model did not achieved good performance simulating winds, especially on changes of direction. The model captures the major variations of zonal wind during summer, however, in some stations, when the flow direction was changed to meridional, the BRAMS simulated an easterly wind, showing a strong dependence on initial conditions. During winter events, after the cyclone cross the AP, the experiments simulated a west wind, which is not consistent with that observed at meteorological stations. In the case of meridional wind, BRAMS intensified the south flows, especially after the cyclone on AP.
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Taxonomia de invertebrados fósseis (Oligoceno-Mioceno) da ilha Rei George (Antártica ocidental) e paleobiogeografia dos Bivalvia cenozóicos da Antártica / Taxonomy of invertebrate fossils (Oligocene-Miocene) from the King George island (West Antarctica) and paleobiogeography of cenozoic Bivalvia from AntarcticaQuaglio, Fernanda 11 October 2007 (has links)
As pesquisas apresentadas nesta dissertação integram o projeto CNPq - PROANTAR 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", que estuda os depósitos cenozóicos da ilha Rei George em busca elucidação do histórico ambiental e climático desta região antártica. A evolução dos padrões de circulação marinha e atmosférica no Hemisfério Sul ocorreu em resposta ao isolamento geográfico e térmico da Antártica, resultado de sua separação da Austrália, no limite Eoceno/Oligoceno, e da América do Sul, no final do Oligoceno. Sob este aspecto, o estudo de organismos fósseis registrados nos depósitos cenozóicos da Antártica contribui para o entendimento das evoluções biológicas e ambientais ocorridas concomitantemente às mudanças paleogeográficas, oceanográficas e climáticas na região ao longo do Cenozóico. Frente à dificuldade de acesso, demanda logística e extensa cobertura de gelo, apenas uma pequena porção do registro geológico da Antártica está acessível para pesquisa. Afloramentos da ilha Rei George registram as mudanças climáticas e ambientais ocorridas do Oligoceno ao Mioceno, incluindo evidências do primeiro evento de glaciação perene no oeste do continente (Oligoceno). A despeito da abundância de fósseis nos estratos cenozóicos da ilha, são poucos os trabalhos taxonômicos com descrição sistemática detalhada de bivalves fósseis. O primeiro módulo do presente estudo apresenta a descrição taxonômica de invertebrados de depósitos cenozóicos aflorantes em duas localidades da ilha Rei George, Antártica ocidental. Da Formação Cape Melville (Mioceno), península Melville, foram descritos sete táxons de bivalves, incluindo seis espécies novas. Da Formação Polonez Cove (Oligoceno), Pico Vauréal, uma região previamente inexplorada paleontologicamente, foram descritos sete táxons de invertebrados (bivalves, braquiópodes, tubos de serpulídeos, briozoários e fragmentos de equinodermes), incluindo duas espécies novas. O segundo módulo corresponde à reunião dos gêneros de bivalves registrados em depósitos cenozóicos da Antártica. A análise do registro apontou para o conhecimento bastante incipiente sobre a diversidade de bivalves antárticos ao longo do Cenozóico. Além disso, a comparação entre gêneros de bivalves cenozóicos registrados na Antártica e Nova Zelândia revelou que a maior parte dos gêneros compartilhados está registrada em depósitos eocênicos, o que suporta o isolamento geográfico da Antártica e a redução do intercâmbio faunístico entre a Antártica e regiões periféricas após o Oligoceno. A análise do registro sugeriu um evento de dispersão intenso durante o Eoceno, e pequenos pulsos de dispersão após o Oligoceno. O padrão de distribuição dos táxons concorda parcialmente com as reconstituições de paleocorrentes disponíveis na literatura. A dispersão durante o Eoceno teria ocorrido da Antártica para a Nova Zelândia na direção do Atlântico para o Pacífico. Este evento de dispersão concorda com a hipótese de existência de conexões marinhas de plataforma rasa entre o oeste e o leste da Antártica (\"Passagem de Shackleton\") e da província Weddeliana do final do Cretáceo ao Eoceno. Os eventos de dispersão pósoligocênicos teriam ocorrido durante e após o estabelecimento da Corrente Circum-Antártica, não mais pela \"Passagem de Shackleton\", mas margeando a Antártica pelas bordas ocidental atlântica e oriental em direção à Nova Zelândia. A análise do registro dos bivalves cenozóicos da Antártica também concorda com a hipótese de glaciação perene a partir do início do Oligoceno na região leste do continente, e na metade do Oligoceno na região oeste, com temperaturas mais amenas que as observadas atualmente. / The research presented in this dissertation comprised part of the CNPq - PROANTAR Project 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", which studies Cenozoic deposits from King George Island in order to elucidate the environmental and climatic Cenozoic histories of this Antarctic region. Cenozoic evolution of marine and atmospheric circulation in the Southern Hemisphere occurred in response to the geographic and thermal isolation of Antarctica, which resulted from the separation of Antarctica from Australia, around Eocene/Oligocene boundary, and from South America, during the late Oligocene. Thus, study of fossil organisms from Antarctic Cenozoic deposits contributes to the understanding of biological and environmental evolutions that accompanied paleogeographic, oceanographic and climatic changes during the Cenozoic. As a result of the difficult access, logistic demand and extensive ice cover, only a small part of the Cenozoic Antarctic record is available for study. King George Island records climatic and environmental changes from the Oligocene to the Miocene, including evidence of the first full-scale glaciation (Oligocene) of West Antarctica. Despite the abundance of fossils in Cenozoic deposits of the island, taxonomic studies with detailed systematic descriptions of bivalves are very rare. The first section of this work consists of taxonomic descriptions of invertebrates from Cenozoic deposits cropping out in two localities of King George Island, West Antarctica. Seven taxa of bivalves, including six new species were described from the Cape Melville Formation (Miocene), at Melville Peninsula. Seven taxa of invertebrates (bivalves, brachiopods, serpulid tubes, bryozoans, and echinoderm fragments) were described from the Polonez Cove Formation (Oligocene), at Vauréal Peak, a site previously unexplored paleontologically. The second section presents the results of a survey of the Cenozoic fossil record of Antarctic bivalves. The analysis of the fossil record confirmed that the current knowledge about the Cenozoic diversity of the group is very scarce. Moreover, comparison of Cenozoic bivalve genera from Antarctica and New Zealand showed that the greatest number of shared taxa is recorded in Eocene deposits. This finding supports the geographic isolation of Antarctic and the drop in faunal interchange between Antarctica and periphery after the Oligocene. Analysis of the fossil record suggested an intensive dispersal event during the Eocene, and restricted pulses of dispersal from the Oligocene onwards. The distribution pattern of taxa provides partial support for available reconstructions of marine currents. Eocene dispersal would have occurred from Antarctica to New Zealand in Atlantic-Pacific direction. This dispersal event is consistent with the hypothesis of shallow marine connections between West and East Antarctica (\"Shackleton Seaway\"), as well of the existence of the Weddellian Province from the Late Cretaceous to the Eocene. Dispersal events following the Oligocene would have occurred during and after the establishment of the Circum-Antarctic Current, along the West-Atlantic and East margins of Antarctica towards New Zealand, and no longer through \"Shackleton Seaway\". These analyses also support the hypothesis of full-scale glaciation in West Antarctica from the early Oligocene onwards, and in East Antarctica since the mid-Oligocene, with warmer temperatures than today.
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Rock weathering, erosion, and sublimation rates of ancient buried ice in the McMurdo Dry Valleys, AntarcticaLamp, Jennifer Lynn 21 June 2016 (has links)
The inland region of the McMurdo Dry Valleys (MDV) of Antarctica represents a subzero, hyper-arid endmember for physical weathering, and is Earth’s closest terrestrial analog to the Martian surface. In order to document the style and rate of rock breakdown in this region, I conducted field-based, experimental, and numerical modeling studies of supraglacial debris (Mullins till) on Mullins Glacier. These investigations were designed to (1) quantify the rate and processes of physical breakdown of surface rocks on Mullins till, particularly of Ferrar Dolerite, (2) determine the efficacy of thermal stress weathering as an agent in rock erosion, and (3) examine the role of physical weathering in altering the sublimation of buried glacial ice.
Results from morphometric field surveys characterizing changes in rock shape, strength, and small-scale surface features, coupled with an iterative cosmogenic nuclide-based age model for Mullins Glacier, show that total erosion rates for clasts of Ferrar Dolerite on Mullins till range from 1.1 to 15 cm Myr-1. In situ field measurements of rock surface temperatures and local ambient conditions recorded at 15-second intervals, combined with a numerical finite element model elucidating changes in internal rock temperatures and associated strain, show that thermal stress weathering is sufficient to induce spalling by propagating existing microcracks of ≥1.1 cm that typically occur at the base of thin, mm-scale alteration rinds. The implication is that thermal stress weathering, previously undocumented in this region, may account for >80% of the total estimated erosion of Ferrar Dolerite. Furthermore, the spalled fragments (up to 5% of Mullins till) provide a negative feedback that slows the rate of subsurface ice sublimation and internal vapor diffusion. Experimental analyses in a controlled environmental chamber set with Mullins till and driven by local meteorological conditions measured in the field yields an average effective diffusivity of 4.5 x 10-6 m2 s-1 for Mullins till and annual rates of buried ice loss of <0.068 mm (assuming Fickian diffusion); these values are consistent with theoretical estimates, demonstrate the importance of physical weathering in modifying supraglacial deposits, and support arguments for persistent cold-desert conditions in the MDV for the last several million years.
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Caracterização tafonômica das concentrações fossilíferas da Formação Cape Melville, Grupo Moby Dick (Mioceno Inferior), Ilha Rei George, Antártica / Taphonomic characterization of fossil concentrations from the Cape Melville Formation, Moby Dick Group (Early Miocene), King Georg Island, AntacticaRafael Casati 01 November 2007 (has links)
Trabalhos objetivando a tafonomia de concentrações fossilíferas geradas em ambiente glacial ou periglacial são raros. Neste contexto, a presente dissertação realizou a caracterização tafonômica das concentrações fossilíferas da Formação Cape Melville, Grupo Moby Dick (Mioceno Inferior), Ilha Rei George, Antártica, tendo em vista a elucidação da gênese destes depósitos. Para tanto, dados relativos a um total de 534 espécimes foram obtidos nas camadas ricamente fossilíferas das quatro seções, denominadas Pingüineira (PRS), Hard Ground (HGS), Chaminé (CS) e Lava Crag (LCS), levantadas no topo da Península Melville entre Janeiro e Fevereiro de 2003. Destas, apenas a Seção PRS apresenta duas camadas fossilíferas distintas (PRS-C1 e PRS-C2). A fauna estudada é composta predominantemente por restos de moluscos bivalves. Restos menos abundantes de corais, caranguejos, gastrópodes e braquiópodes, além de icnofósseis, também estão presentes. A análise da composição taxonômica, ecológica e tafonômica permitiu identificar semelhanças entre as Seções PRS e HGS e entre as Seções CS e LCS. As seções PRS e HGS são compostas dominantemente por bivalves depositívoros da infauna rasa (Ennucula frigida, Enncula musculosa e Yoldia peninsularis), preservados preferencialmente com as valvas articuladas fechadas, porém fora da posição de vida, indicando remobilização da fauna pré-soterramento; a ausência de sinais de fragmentação, abrasão e incrustação indica que os bioclastos não foram afetados por processos bioestratinômicos químicos, físicos ou biológicos intensos. A ocorrência de bioclastos piritizados na Seção HGS é interpretada como resultante da decomposição dos organismos soterrados, ainda vivos, em ambiente anóxico. As assembléias das seções CS e LCS são constituídas dominantemente por bivalves suspensívoros da infauna profunda (Neilo (N.) rongelii), preservados preferencialmente com as valvas desarticuladas, indicando que os processos bioestratinômicos físicos foram mais atuantes, sendo, no entanto, raros os sinais de fragmentação e de outras assinaturas tafonômicas como incrustação e bioerosão. As valvas desarticuladas estão preservadas preferencialmente com a convexidade voltada para baixo indicando que os bioclastos foram colocados em suspensão e redepositados fora da posição de maior estabilidade hidrodinâmica; a orientação em planta destes bioclastos exibe direção preferencial, indicando atuação de correntes fracas e um maior tempo de exposição na interface água/sedimento; a ocorrência de raros restos de bivalves suspensívoros escavadores da infauna profunda (Panopea (P.) cf. P. regularis) e de caranguejos (Antarctidromia inflata) preservados em posição de vida é indicativa de que esta comunidade foi soterrada in situ por sedimentos em suspensão que trouxeram a tanatocenose de valvas desarticuladas. Os resultados obtidos no presente estudo reiteram a importância dos estudos tafonômicos e paleoecológicos no entendimento da dinâmica deposicional do passado, contribuindo com um grande conjunto de dados úteis na caracterização de ambientes glaciais e periglaciais. / Works focusing on the taphonomy of fossil concentrations generated in glacial or periglacial environment are rare. In this context, the present dissertation carried out the taphonomic characterization of the fossil concentrations of the Cape Melville Formation, Moby Dick Group (Lower Miocene), King George Island, Antarctica, in order to elucidate the genesis of these deposits. To this end, data relative to a total of 534 specimens were obtained in the richly fossil layers of the four sections, called Pingüineira (PRS), Hard Ground (HGS), Chaminé (CS) and Lava Crag (LCS), investigated at the top of the Melville Peninsula between January and February of 2003. Of these, only the PRS Section presents two distinct fossil layers (PRS-C1 and PRS-C2). The studied fauna is mainly composed of remains of bivalve clams. Less abundant remains of corals, crabs, gastropods and brachiopods, as well as trace fossils, also are present. Taxonomic, ecological and taphonomic analyses allowed similarities to be identified between PRS and HGS and CS and LCS. PRS and HGS Sections are dominantly composed by shallow infaunal deposit-feeding bivalves (Ennucula frigida, Enncula musculosa Yoldia peninsularis), preserved preferentially with closed articulated valves, however out of life position, indicating remobilized fauna; the absence of signs of spalling, abrasion and incrustation indicates that the bioclasts were not affected by intense chemical, physical or biological bioestratinomic processes. The occurrence of pyritized bioclasts in HGS is interpreted as the result of decomposition of the entombed organisms, still alive, in an anoxic environment. The assemblages of CS and LCS Sections are dominantly constituted by deep infaunal suspension-feeding bivalves (Neilo (N.) rongelii), preserved preferentially with disarticulated valves, indicating that the physical biostratinomic processes were more operative; however there are few signs of spalling or other taphonomic signatures such as incrustation and bioerosion. Disarticulated valves are preferentially preserved convex down indicating that bioclasts were placed in suspension and redeposited in a position other than that of greatest hydrodynamic stability; the orientation of these bioclasts in plan view shows a preferential direction, indicating weak currents and a longer time of exposition at the water/sediment interface; the occurrence of rare remains of deep infaunal suspension-feeding bivalves (Panopea (P.) cf. P. regularis) and crabs (Antarctidromia inflata) preserved in life position is indicative that this community was entombed in situ by sediments in suspension that brought the thanatocenosis of disarticulated valves. The results obtained in the present study reiterate the importance of taphonomic and paleoecological studies for the understanding of the depositional dynamics of the past and contribute a great number of data useful in the characterization of glacial and periglacial environments.
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Taxonomia de invertebrados fósseis (Oligoceno-Mioceno) da ilha Rei George (Antártica ocidental) e paleobiogeografia dos Bivalvia cenozóicos da Antártica / Taxonomy of invertebrate fossils (Oligocene-Miocene) from the King George island (West Antarctica) and paleobiogeography of cenozoic Bivalvia from AntarcticaFernanda Quaglio 11 October 2007 (has links)
As pesquisas apresentadas nesta dissertação integram o projeto CNPq - PROANTAR 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", que estuda os depósitos cenozóicos da ilha Rei George em busca elucidação do histórico ambiental e climático desta região antártica. A evolução dos padrões de circulação marinha e atmosférica no Hemisfério Sul ocorreu em resposta ao isolamento geográfico e térmico da Antártica, resultado de sua separação da Austrália, no limite Eoceno/Oligoceno, e da América do Sul, no final do Oligoceno. Sob este aspecto, o estudo de organismos fósseis registrados nos depósitos cenozóicos da Antártica contribui para o entendimento das evoluções biológicas e ambientais ocorridas concomitantemente às mudanças paleogeográficas, oceanográficas e climáticas na região ao longo do Cenozóico. Frente à dificuldade de acesso, demanda logística e extensa cobertura de gelo, apenas uma pequena porção do registro geológico da Antártica está acessível para pesquisa. Afloramentos da ilha Rei George registram as mudanças climáticas e ambientais ocorridas do Oligoceno ao Mioceno, incluindo evidências do primeiro evento de glaciação perene no oeste do continente (Oligoceno). A despeito da abundância de fósseis nos estratos cenozóicos da ilha, são poucos os trabalhos taxonômicos com descrição sistemática detalhada de bivalves fósseis. O primeiro módulo do presente estudo apresenta a descrição taxonômica de invertebrados de depósitos cenozóicos aflorantes em duas localidades da ilha Rei George, Antártica ocidental. Da Formação Cape Melville (Mioceno), península Melville, foram descritos sete táxons de bivalves, incluindo seis espécies novas. Da Formação Polonez Cove (Oligoceno), Pico Vauréal, uma região previamente inexplorada paleontologicamente, foram descritos sete táxons de invertebrados (bivalves, braquiópodes, tubos de serpulídeos, briozoários e fragmentos de equinodermes), incluindo duas espécies novas. O segundo módulo corresponde à reunião dos gêneros de bivalves registrados em depósitos cenozóicos da Antártica. A análise do registro apontou para o conhecimento bastante incipiente sobre a diversidade de bivalves antárticos ao longo do Cenozóico. Além disso, a comparação entre gêneros de bivalves cenozóicos registrados na Antártica e Nova Zelândia revelou que a maior parte dos gêneros compartilhados está registrada em depósitos eocênicos, o que suporta o isolamento geográfico da Antártica e a redução do intercâmbio faunístico entre a Antártica e regiões periféricas após o Oligoceno. A análise do registro sugeriu um evento de dispersão intenso durante o Eoceno, e pequenos pulsos de dispersão após o Oligoceno. O padrão de distribuição dos táxons concorda parcialmente com as reconstituições de paleocorrentes disponíveis na literatura. A dispersão durante o Eoceno teria ocorrido da Antártica para a Nova Zelândia na direção do Atlântico para o Pacífico. Este evento de dispersão concorda com a hipótese de existência de conexões marinhas de plataforma rasa entre o oeste e o leste da Antártica (\"Passagem de Shackleton\") e da província Weddeliana do final do Cretáceo ao Eoceno. Os eventos de dispersão pósoligocênicos teriam ocorrido durante e após o estabelecimento da Corrente Circum-Antártica, não mais pela \"Passagem de Shackleton\", mas margeando a Antártica pelas bordas ocidental atlântica e oriental em direção à Nova Zelândia. A análise do registro dos bivalves cenozóicos da Antártica também concorda com a hipótese de glaciação perene a partir do início do Oligoceno na região leste do continente, e na metade do Oligoceno na região oeste, com temperaturas mais amenas que as observadas atualmente. / The research presented in this dissertation comprised part of the CNPq - PROANTAR Project 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", which studies Cenozoic deposits from King George Island in order to elucidate the environmental and climatic Cenozoic histories of this Antarctic region. Cenozoic evolution of marine and atmospheric circulation in the Southern Hemisphere occurred in response to the geographic and thermal isolation of Antarctica, which resulted from the separation of Antarctica from Australia, around Eocene/Oligocene boundary, and from South America, during the late Oligocene. Thus, study of fossil organisms from Antarctic Cenozoic deposits contributes to the understanding of biological and environmental evolutions that accompanied paleogeographic, oceanographic and climatic changes during the Cenozoic. As a result of the difficult access, logistic demand and extensive ice cover, only a small part of the Cenozoic Antarctic record is available for study. King George Island records climatic and environmental changes from the Oligocene to the Miocene, including evidence of the first full-scale glaciation (Oligocene) of West Antarctica. Despite the abundance of fossils in Cenozoic deposits of the island, taxonomic studies with detailed systematic descriptions of bivalves are very rare. The first section of this work consists of taxonomic descriptions of invertebrates from Cenozoic deposits cropping out in two localities of King George Island, West Antarctica. Seven taxa of bivalves, including six new species were described from the Cape Melville Formation (Miocene), at Melville Peninsula. Seven taxa of invertebrates (bivalves, brachiopods, serpulid tubes, bryozoans, and echinoderm fragments) were described from the Polonez Cove Formation (Oligocene), at Vauréal Peak, a site previously unexplored paleontologically. The second section presents the results of a survey of the Cenozoic fossil record of Antarctic bivalves. The analysis of the fossil record confirmed that the current knowledge about the Cenozoic diversity of the group is very scarce. Moreover, comparison of Cenozoic bivalve genera from Antarctica and New Zealand showed that the greatest number of shared taxa is recorded in Eocene deposits. This finding supports the geographic isolation of Antarctic and the drop in faunal interchange between Antarctica and periphery after the Oligocene. Analysis of the fossil record suggested an intensive dispersal event during the Eocene, and restricted pulses of dispersal from the Oligocene onwards. The distribution pattern of taxa provides partial support for available reconstructions of marine currents. Eocene dispersal would have occurred from Antarctica to New Zealand in Atlantic-Pacific direction. This dispersal event is consistent with the hypothesis of shallow marine connections between West and East Antarctica (\"Shackleton Seaway\"), as well of the existence of the Weddellian Province from the Late Cretaceous to the Eocene. Dispersal events following the Oligocene would have occurred during and after the establishment of the Circum-Antarctic Current, along the West-Atlantic and East margins of Antarctica towards New Zealand, and no longer through \"Shackleton Seaway\". These analyses also support the hypothesis of full-scale glaciation in West Antarctica from the early Oligocene onwards, and in East Antarctica since the mid-Oligocene, with warmer temperatures than today.
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The case of regulation of mobile money in Malaŵi : law and practiceMadise, Sunduzwayo January 2017 (has links)
The emergence of mobile money and other new forms of payment has changed the sovereign foundations of money. Starting as a DFID funded project in Kenya, mobile money has now spread to many countries including Malaŵi. This thesis looks at the regulatory issues that mobile money poses, and the risks that this alternative form of payment poses to the financial system. The thesis argues that the traditional regulatory architecture of supervising the financial services is ill-suited to supervise mobile money. There are essentially two models of mobile money: telco-led and bank-led. The first is an innovation by telecommunication operators and utilises the small messaging service. There is no requirement to own a bank account. The bank-led model is linked to a bank account. The regulatory approaches to these two models are different. Unlike the telco-led, the bank-led model is under prudential regulation. This has manifested itself in the way the services have developed. The telco-led model had thrived while the bank-led model has fizzled indicating that for mobile money, less regulation may be an enabler. Mobile money is now considered a key developmental tool to achieve financial inclusion among the poor, rural based, unbanked, and underbanked. As opposed to traditional additive forms of financial inclusion, mobile money, especially the telco-led, is transformative. It employs a different approach where the consumer does not have to have a bank account or even travel to a bank to access financial services. In Malaŵi, the financial regulatory framework largely embodies the command and control model. Mobile money, however has largely been regulated using light-touch, with regulation following innovation. This thesis proposes an approach based on the concept of really responsive regulation. This approach, is best suited to embrace mobile money as it passes through the different phases of its evolution.
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The aftermath of the Milk Scandal of 2008 : the challenges of Chinese systemic governance and food safety regulationLi, Yanjie January 2015 (has links)
Food safety problems set an enormous challenge to China’s sustainable economic development. The Milk Scandal of 2008 brought public attention to the poor regulation and ineffective administration of the food industry. This highlighted the fact that food safety is relevant to the public health and the brand ‘Made in China’ in international trading. It also shows how food safety law and better environmental protection has arisen out of a crisis. The milk scandal brought an influx of foreign products into China and opened up the Chinese market to international influence and food standards that would not have been possible before the crisis began. Sustaining China’s environmental future is a work-in-progress with uncertain outcomes but there is an admission that without solving the food safety problem, China cannot achieve its sustainable economic development. This thesis examines China’s current food safety legislation in the aftermath of the milk scandal of 2008. The thesis raises the question of how China deals with its food safety crisis and regulates its food industry to cope with its sustainable economic development. It also considers how best for the Chinese and the rest of the world may be able to learn from the Chinese experience. In the aftermath of the Chinese food crisis, China found itself subject to imports from abroad. This had a two-fold effect. It brought international regulatory practices into Chinese life; the second effect was to awaken China to the demands of international trade and the need to conform to best practice. It also showed how China had to meet expectations that were informed by international experience, which China sadly lacked. A deeper analysis is that China was exposed to the dilemma of profit driven organisations failing to appreciate the role of regulation and the safety of ordinary people. The scandal exposed many institutional and organisational shortcomings while the lessons were clear for anyone who looked. Placing profits over the preservation of social order and stability resulted in short-term gains with few long term benefits. This research provides a comprehensive analysis and offers a perspective of the Chinese food safety problem from the legal, social and economic context of the problem. The causes of the food safety problem in China are complex. The food safety problem is not only caused by the defect of the food safety legislation itself. Other factors, such as environmental challenges and the irresponsible business activities, all contribute to the ineffectiveness of the food safety regulatory system. The thesis starts with the Milk Scandal of 2008 to examine the current food safety regulatory system in China. It addresses the main systemic problem, which leads to the weak implementation and ineffective administrations, and it also finds out that apart from the systemic defects, the environmental problem and the failure of the private sector all have an impact on the food safety regulatory system. Furthermore, the thesis also explores the new innovations in the 2014 Environmental Protection Law, which may potentially contribute to the food safety law in the future. The private sector has also been examined. The fact is found that Chinese companies are operated in an irresponsible way, which causes the consecutive food scandals in China. The role of corporate social responsibility is also considered to guide the business activities in practice. The interests of the stakeholders, such as consumers, need to be addressed in the decision-making. The final conclusion is China still has a long way to go to achieve its sustainable economic development. The legislation system needs to be completed and unified. The effectiveness of the administration needs to be improved and independent judiciary needs to be built up. Besides the systemic problem, the improvement of the environment and the responsible business operation also contribute to re-shaping an effective food safety regulatory system. The innovation in the Environmental Law of 2014 can also be introduced to the food safety system. The citizen-driven approach can be used as an important supplement to China’s traditional state-centred approach, to overcome the systemic weakness in the implementation of the food safety law. Many disasters in the world are discussed in terms of the experiences countries may gain from bad events. Bhopal and Chernobyl are two examples. The Chinese Milk Scandal stands in a line of disasters such as BSE in Britain that have re-oriented the regulatory map. Stakeholders and citizens have much to gain from learning the lessons of the milk scandal.
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