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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.
111

Emergence and growth of seven grass species across a gradient of metals and arsenic in lime-amended contaminated soils

Martin, Tara Noel. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Dennis Neuman. Includes bibliographical references (leaves 124-138).
112

Caracterização hidrológica e biogeoquímica de microbacias: uma comparação entre Mata Atlântica e Pinus taeda L. / Hydrological biogeochemical characterization of small catchments: a comparison between Rainforest and Pinus taeda L.

Maureen Voigtlaender 26 April 2007 (has links)
No Estado do Paraná, o setor industrial de papel e celulose possui aproximadamente 200 mil hectares de área reflorestada com Pinus . A crescente demanda vem impulsionando a implantação de novas áreas, sendo imprescindível a otimização do uso da área que se apresenta como o fato central da sustentabilidade. Neste contexto, não somente o que diz respeito à produtividade propriamente dita, mas aspectos relativos à qualidade ambiental, como os recursos hídricos e a conservação do solo são importantes para a conservação do ecossistema. Esse trabalho teve como objetivo principal caracterizar a dinâmica hidrológica e a biogeoquímica de duas microbacias, cobertas respectivamente, por Mata Atlântica e Pinus taedaL. As microbacias localizadas na região centro-leste do Estado do Paraná, no Município de Telêmaco Borba, foram selecionadas com a finalidade de realizar medições de precipitação e vazão, durante o período de agosto de 2005 a julho de 2006, e principalmente quantificar o balanço dos nutrientes. De acordo com os resultados, concluiu-se que as duas microbacias apresentaram características semelhantes para a dinâmica hidrológica, para as propriedades do solo e, principalmente para o balanço geoquímico dos nutrientes. Portanto, essas constatações apóiam a hipótese para futuras comparações entre as duas microbacias e permitem inferir que prováveis mudanças que possam ocorrer poderão ser atribuídas às práticas do manejo florestal. / In the State of Paraná, Brasil, the pulp and paper industry holds about 200 thousand hectares of Pine plantatios. An increasing demand has been stimulating the implantation of new areas and this fact requires the optimization of land use practices, that which is itself a central fact for sustainability. In this context, not only from the perspective of the productivity, itself, but also in regards to environmental aspects, such as water resources and the conservation of the soil, which are important for the conservation of the ecosystem. The main objective, of this work was to characterize the hydrological and biogeochemical dynamics of two small catchments, covered wither Rainforest and Pinus taeda L. plantation. The catchments, located in the center east region of the Paraná State, in the municipality of Telêmaco Borba, were selected with the purpose of water balance calculation through continuous measurement of precipitation and streamflow, during the period of August of 2005 until July of 2006, and, mainly, the estimation of the catchment nutrients budget. The results showed that the two catchments presented similar characteristics in hydrological dynamics, as well an in soil properties and, mainly, in the geochemical nutrients budgets. Therefore, these evidences support the hypothesis for future comparisons between the two catchments and allow inferring that probable changes that can occur might be attributed to the practical forest management in one of them.
113

Sistemática para seleção de tecnologias de tratamento de efluentes : uma análise multicriterial aplicada à bacia hidrográfica

Reis, Adriana de Oliveira Pereira dos January 2018 (has links)
O processo de seleção de uma tecnologia de tratamento de esgoto envolve a análise de diferentes fatores como as características dos efluentes brutos, demanda por energia e material humano qualificado, disponibilidade de terreno, condições climáticas, geração de subprodutos e sua destinação final e capacidade suporte dos cursos d’água receptores, dentre outros. O processo de seleção torna-se mais complexo quando conduzido no âmbito de uma bacia hidrográfica, uma vez que deverão ser considerados corpos d’águas com diferentes capacidades de autodepuração e a disposição final de efluentes com diferentes vazões e condições de qualidade. Este trabalho teve como objetivo central estabelecer uma metodologia que permita a seleção de sistemas de tratamento, no âmbito de bacias hidrográficas, considerando o emprego combinado de modelagem matemática de qualidade de água, técnica de otimização e método de análise multicriterial. Ainda que aplicável a quaisquer bacias hidrográficas, a metodologia proposta foi aplicada à Bacia Hidrográfica do Rio Pardo, curso d´água localizado na porção sul do estado do Espírito Santo. Eficiências mínimas de remoção de matéria orgânica, estimadas com emprego combinado de modelo matemático de qualidade de água e técnica de otimização, permitiram a pré-seleção dos sistemas de tratamento de esgoto, observadas a manutenção dos padrões de qualidade dos corpos d’água e/ou dos efluentes e a equidade no esforço de tratamento entre os diferentes sistemas objetos da seleção. Uma pesquisa qualitativa, conduzida por grupos focados, permitiu a validação dos subsistemas sociotécnicos (Ambiental, Tecnológico, Operação e Social) e dos critérios de seleção. A partir do emprego do método baseado na Teoria de Utilidade Multiatributo (MAUT) foi apropriado um Índice Sociotécnico que permitiu estabelecer, por localidade da área de estudo, o ranking das tecnologias de tratamento de esgoto pré-selecionadas. Para as sedes municipais de Ibatiba e Iúna (maiores aglomerados urbanos da área de estudo), o Índice Sociotécnico conduziu à priorização de variações dos sistemas de lodos ativados ou de tanque sépticos com biodisco como opções de tratamento. Para a sede do município de Irupi e para os povoados de Santíssima Trindade e Nossa Senhora das Graças, função da capacidade de autodepuração dos cursos d’água e/ou dos pequenos contingentes populacionais, o Índice Sociotécnico conduziu à priorização de sistemas mais simples, como diferentes variações do sistema de lagoas de estabilização. / The selection process of a sewage treatment technology involves the analyses of different factors, such as, the characteristics of raw effluents, electricity and qualified human material demand, land availability, weather conditions, production of by-products and final destination and bearing capacity of water resources, among others. The selection process becomes more complex when carried out in a river basin ambit, once water bodies with capacities of selfdepuration and the final destination of effluents with different outflows and quality conditions must be taken into consideration. This work’s main goal was to establish a methodology that enabled the selection of systems of treatment, in river basin ambits, considering the combined use of water quality mathematical modelling, optimization technique and the method of multicriterial analysis. Even applicable to any river basin, the methodology proposed was applied to Rio Pardo river basin, watercourse located in the south of Espírito Santo State. Minimum efficiencies of organic material removal, estimated with the combined use of water quality mathematical modelling and optimization technique, allowed the pre-selection of sewage treatment systems, observed the maintenance of quality standards of water bodies and/or effluents and the equity regarding the treatment effort among the selection’s objects systems. A qualitative research, conducted by focus groups, allowed the validation of socio-technical subsystems (Environmental. Technological, Operation and Social) and the selection criteria. By using the method based on the Multi-attribute Utility Theory (MAUT), an Environmental Index was settled in order to allow the establishment, according to the study area location, of a ranking of pre-selected sewage treatment technologies. For the municipal headquarters in Ibatiba and Iúna (the biggest urban settlements within the study area), the Environmental Index conducted the prioritization of systems variations of activated sludge or septic tank with biodiscs as options for treatment. As for the municipal headquarter in Irupi and the Santíssima Trindade and Nossa Senhora das Graças villages, the self-depuration capacity function of the watercourses and/or small population contingent, the Environmental Index led to the prioritization of more simple systems, with different variations of the stabilization ponds system.
114

Modelling of pesticides and POPS in the River Thames system : potential impacts of changes in climate and management

Lu, Qiong January 2017 (has links)
Due to environmental concerns, most of persistent organic pollutants (POPs) have been eliminated or reduced in production and use; however, due to their great persistency, POPs are expected still to be found in the environment long after their use has ceased. Although, in recent years, POPs have rarely been detected in river water in the United Kingdom (UK), their concentrations in fish (biota) and sediment are expected to be notable due to their lipophilicity and bioaccumulation; however, there is a lack of information and data to understand the current contamination of POPs in catchments and evaluate their potential risk to the environment and ecosystem. This thesis describes the application of mathematical modelling approaches to (i) predict the current distribution and concentration of POPs in catchments, (ii) evaluate the influence of climate change and extreme weather conditions on the fate of POPs, and (iii) provide guidelines to inform decision-making on managing the potential risks of POPs in river basins. The modelling studies have mainly focused on polychlorinated biphenyls (PCBs). The River Thames catchment was chosen as the study area. The Fugacity level III model was initially used to describe the general distribution of PCBs between different compartments; it was predicted that the greatest mass of PCBs remain in the soil, but the fish and sediments represent compartments with the highest PCB concentrations. The contamination of PCBs in Thames fish was estimated to exceed the unrestricted consumption thresholds of 5.9 μg/kg for ∑PCBs set by the U.S. Environmental Protection Agency (EPA); no current EU Environmental Quality Standards (EQS) are available for PCBs in fish. It was indicated that the PCBs in fish could be linked to PCB contamination in sediment, which was predicted to be about three times higher than the fish concentrations, but insufficient observed data of PCBs in Thames fish and sediment are available to validate the results. In order to address this limitation in observed data, fish and sediment sampling and chemical analysis were carried out for the presence of POPs. In addition to PCBs, the measured results for hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) in Thames fish and sediment were assessed. Although the observed fish- and sediment concentrations of the chemicals appear quite variable, when normalised to organic carbon the levels in sediment, they were comparable to the fish lipid normalised concentrations. Using the temperature and rainfall data forecasts in the UK Climate Projections 2009 (UKCP09), climate change scenarios were established and assessed in the fugacity modelling. The modelling results suggested a modest influence of climate change on PCB fate over the next 80 years. The most significant result was a tendency, in the Thames catchment, for climate change to enhance the evaporation of PCBs from soil to air. While the fugacity model successfully simulated the distribution and fate of PCBs, we used greatly simplified representations of climate, hydrology and biogeochemical processes of the catchment: to have a deeper understanding, a newly developed dynamic hydrobiogeochemical transport model - the Integrated Catchment Contaminants model (INCAContaminants) was applied. Using additional information about weather, river flows and water chemistry, the INCA-Contaminants model provided new insights into the behaviour of contaminants in the catchment; this led to a better representation of PCB contamination in sediment. In addition, INCA demonstrated the important impact of short-term weather variation on PCB movement through the environment. It was shown that PCBs contamination in Thames sediment was greatly disturbed by the severe flooding that occurred in early 2014. This thesis presents the application of the INCA model to assess - in addition to POPs - the behaviour of metaldehyde in the River Thames catchment. Metaldehyde is a type of pesticide used mainly to kill snails and slugs. Its application in agricultural areas within the catchment area has in recent years caused severe problems with drinking water supply. The INCA model has proved to be an effective tool for simulating the transport of metaldehyde in the catchment, predicting observed metaldehyde concentrations at multiple locations in the River Thames; this is the first time that a dynamic modelling approach has been used to predict the behaviour of metaldehyde in river basins. Modelling results showed that high concentrations of metaldehyde in the river system are a direct consequence of excessive application rates. In this thesis, a simple decision-support tool was derived from modelling results, based on variable application rates and application areas. This decision-support tool is now being used by Thames Water to help control peak concentrations of metaldehyde at key water supply locations.
115

Hierarquia espacial de sub-bacias hidrográficas como unidades de planejamento de conservação de sistemas aquáticos continentais

Domecq Rolón, Federico Arturo Monte January 2012 (has links)
Em planejamento de conservação aquática, abordagens quantitativas são realizadas ao longo de varias unidades de paisagem. Muitas vezes, as divisões internas como unidades de planejamento são definidas subjetivamente e condicionadas á disponibilidade de dados físicos y biológicos. Bacias hidrográficas como unidades de planejamento são subdividas e classificadas com base em contextos geológicos e climáticos, fisiográficos e biogeográficos que seguem escalas espaciais hierárquicas como subbacias, trechos e segmentos de rios até macro/micro habitats. Reconhecem-se fatores de grande escala espacial e temporal como condicionantes da expressão de padrões e processos (físicos e biológicos) a escalas menores e de maneira hierárquica. Mais além, existe uma interdependência destes (padrões e processos) operando através de múltiplas escalas. Na construção de abordagens de planejamento mais flexíveis e gerais, bacias e subbacias têm sido apontadas como escalas apropriadas de captura de fatores que influenciam (direta ou indiretamente) padrões biológicos observados a escalas menores. No entanto, a resolução espacial de subbacias como unidades de classificação poderia afetar os padrões encontrados? Poderia afetar também processos de planejamento de conservação? Neste contexto, analisamos a classificação de subbacias aninhadas em seis níveis hierárquicos de refinamento espacial com base em atributos topográficos da paisagem (altitude, declividade, formas de terreno, vegetação pretérita, posição de subbacias na rede, etc.) dentro da Bacia Hidrográfica do rio Taquari Antas no Rio Grande do Sul - Brasil (26000 km2). Através de uma abordagem quantitativa e análises multivariadas (ordenação e agrupamento), obtivemos basicamente o mesmo padrão espacial de organização através da hierarquia. Determinamos até oito tipos ou grupos de subbacias, influenciadas principalmente por altitude e declividade combinadas com diferentes formas de terreno e vegetação. Foram diferenciadas subbacias de planalto e planície nos extremos, e subbacias do curso principal superior, curso médio e áreas de transição desde morros altos, para morros em vales de rios encaixados, até áreas de encostas abertas e morros em planícies. Classificações com base em níveis hierárquicos de subbacias são importantes no sentido de obter alvos gerais para planejamento de conservação (como subunidades ecorregionais aquáticas). Desta maneira se contribui ao processo de geração de procedimentos e ferramentas de classificação mais flexíveis para planejamento de conservação aquática e com maior confiabilidade. / In freshwater conservation planning, quantitative classification approaches are performed across several landscape units. In general, internal divisions as planning units are subjective and depend on previous knowledge and information available. Usually, river basins are subdivided and grouped based on geology, climate, physiography and biogeographical context, following hierarchical spatial scales, such as sub-basins, reaches, segments, and macro-habitats. There is consensus that factors operating at great spatial and temporal scales constrict processes and patterns (physical and biological) expressed at finer scales, following a hierarchical organization. Furthermore, the interpendence between physical and biological patterns and processes (geomorphology, hydrology, ecology) is recognized to act at multiple scales. Towards more flexible and general planning approaches, basins and sub-basins are pointed as scales that capture the large scale factors that influence (directly or indirectly) the biological patterns observed at lower scales. Does the spatial resolution (area) of sub-basin division used to perform the classification affect the pattern obtained? Can this subject affect the conservation planning process? We analyzed the classification on Taquari Antas river basin (south Brazil) (26000 km2) along six spatially nested sub-basin classification, based on physiographic attributes. Through a quantitative approach and multivariate analyses (cluster and ordination), we obtained basically the same spatial pattern of organization across the hierarchy. The eight sub-basin types or groups where most influenced by elevation and slope, combined with landform classes and original vegetation. Extreme gradients of these attributes express plain region in the plateau and floodplains in lower gradient rivers. Between these extremes, the mainstem river and main tributaries where classified in four distinct groups of subbasins, based on the continuum of physiographical factors. Classifications based on nested hierarchical levels of sub-basins are important to get general coarse targets for freshwater conservation planning. These work contribute to the process of generating more flexible hierarchical classification frameworks for freshwater conservation planning.
116

Paisagens em transformação na bacia hidrográfica do rio Tramandaí: tendências, desafios e contribuições para a gestão ambiental

Castro, Dilton de January 2017 (has links)
A bacia hidrográfica do rio Tramandaí constitui-se importante porção do território gaúcho, muito frequentado por sua localização no litoral norte do Rio Grande do Sul, o que tem implicado em apropriações de espaço e demanda por água e esgoto. Uma de suas lagoas, a dos Quadros, é um dos principais corpos hídricos da Bacia Hidrográfica do Rio Tramandaí, tanto pela sua importância em conservação da biodiversidade, quanto para os usos múltiplos de sua água, como abastecimento público, irrigação, pesca e lazer. Esta pesquisa se propõe a analisar a paisagem em transformação no âmbito da bacia hidrográfica, destacando a área de preservação permanente no entorno da lagoa dos Quadros. São considerados os atributos paisagísticos de estrutura, forma, função e dinâmica para a análise sócio-espacial e temporal. A partir de imagens de satélite de 2005 e 2015, anos de ocorrência de estiagem e de alta pluviometria respectivamente, fotografias aéreas e visitas técnicas ao local, são comparados os usos da terra na bacia hidrográfica e nas área de preservação permanente do entorno da lagoa A contribuição para a gestão ambiental é provocada pela revisão dos diversos instrumentos incidentes na área da bacia e pela observação da variação climática, levando à reflexão sobre os limites impostos pela legislação ambiental para definir as áreas de preservação permanente para lagoas costeiras do Rio Grande do Sul e, consequentemente, às funções ecológicas, sociais e econômicas que se propõe a conservar. Os resultados evidenciam, primeiro, que a bacia hidrográfica tem sofrido alterações significativas quanto ao uso do solo, com expansão urbana, agricultura e silvicultura ocupando espaços de áreas naturais. E, segundo, a delimitação legal da área de preservação permanente no entorno da lagoa – ao não considerar a estrutura ecossistêmica, com suas formas de vida típicas do ambiente às margens da lagoa, tampouco a variação que o clima pode trazer em períodos secos ou chuvosos – não cumpre com a função ecológica que se propõe a realizar. O estudo da paisagem possibilitou entender como os processos socioeconômicos e legais vêm alterando as características naturais da bacia hidrográfica do rio Tramandaí e inferir as tendências de uso futuro da terra e da água. / The Tramandaí River Basin constitutes an important portion of the territory of Rio Grande do Sul, highly popular for its location in the northern coast of the state – which implies appropriation of space, and water and sewage demand. One of its lagoons, Lagoa dos Quadros, is one of the main bodies of water of the Tramandaí River Basin, as much by its importance in biodiversity conservation, as by the multiple uses of its water, such as public water supply, irrigation, fishing and leisure. This research intends to analyze the changing landscape around the river basin, highlighting the protected areas around Lagoa dos Quadros. Landscape attributes – structure, form, function and dynamics – are considered for the socio-spatial and temporal analysis. By means of satellite images from 2005 and 2015, years of drought and high precipitation, respectively, aerial photographs and technical visits, it is possible to compare the land uses in the river basin and in the fully protected areas around the lagoon. The contribution to environmental management is due to the review of the several incident instruments in the area of study and to the observation of the climatic variation. This leads to the discussion of the limits established by environmental law to define the protected areas of coastal lagoons of Rio Grande do Sul, which, consequently, leads to the discussion of the ecological, social and economic purposes that it intends to conserve. The results show, first, that the river basin has been subject to significant alterations with regard to the land use, with urban sprawl, agriculture and silviculture occupying natural areas. And, second, that the delimitation of the areas around the lagoon to be fully protected – by neither considering the ecosystemic structure, with its typical life forms at the margins of the lagoon, nor the variation that the climate can bring in periods of drought or high precipitation – does not fulfill its ecological function. The study of the landscape made it possible to understand how the socioeconomic and legal processes have been altering the natural characteristics of the Tramandaí River Basin and to deduce the trends of future land and water use.
117

Comitês de bacia hidrográfica do Estado do Rio de Janeiro: avanços e dificuldades na gestão das águas. / River Basin Committees of the Rio de Janeiro State: Improvements and Difficulties in Water Management.

Patricia Lemos de Vasconcellos 05 May 2014 (has links)
Uma nova Constituição Federal foi estabelecida no final dos anos 80 conferindo à sociedade civil o direito de participar ativamente nas tomadas de decisões em diversas áreas, como a de recursos hídricos, através de representações de segmentos sociais. No contexto da gestão participativa das águas, o Estado do Rio de Janeiro instituiu sua Política Estadual de Recursos Hídricos, pela Lei n 3.239 em 1999, e criou o Sistema Estadual de Gerenciamento de Recursos Hídricos. Dentro das diretrizes estabelecidas pela Lei das Águas, nove comitês fluminenses foram criados, de acordo com as divisões de bacias hidrográficas. Este trabalho propõe analisar os comitês de bacia, quanto ao desempenho de suas atribuições, através de uma pesquisa qualitativa junto aos membros titulares desses colegiados. Com metodologia baseada no conceituado Projeto Marca dÁgua, um extenso questionário foi aplicado utilizando-se de uma plataforma Survey via internet, onde no total coletou-se 112 respostas. Dos resultados, no geral, conclui-se que os Comitês fluminenses vivem um momento de progresso e que a gestão realizada vem demonstrando resultados satisfatórios. / A new Constitution was established at the end of the 1980s, allowing civil society to take part actively in decision-making in several areas, such as the one of water resources, through representatives from specific social segments. In the context of participatory management of water resources, Rio de Janeiro State has set up its Water Resources State Policy, through the Law n3.239, in 1999, and created the State System of Water Management. According to the policy established by the Law of Waters, nine committees were created, one for each river basin. This study analyzes the river basin committees as to their performance, through a qualitative research which was conducted with their members. The methodology applied was based on the highly esteemed study of the Watermark Project. Each committee member was given an online questionnaire in the Survey platform. The total amount of answers collected was of 112. From the results, the conclusion was that the committees in Rio de Janeiro are experiencing a moment of progress and that the management measures have demonstrated satisfactory results.
118

Variabilidade pluviométrica e a dinâmica atmosférica na bacia hidrográfica do rio Ivaí-PR

Baldo, Maria Cleide [UNESP] 25 April 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-04-25Bitstream added on 2014-06-13T20:22:11Z : No. of bitstreams: 1 baldo_mc_dr_prud.pdf: 5937302 bytes, checksum: fa59fda4cf03f83eefd28617ad952776 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esta pesquisa objetivou analisar a dinâmica climática e a variabilidade pluviométrica para a determinação do padrão de precipitação predominante em diferentes escalas de análise e estabelecer a atuação dos sistemas atmosféricos e sua participação na geração de chuvas através da metodologia de análise rítmica proposta por Monteiro (1971). A bacia do rio Ivaí ocupa uma área de 35.845km2, sendo a segunda maior no território paranaense. Na primeira etapa do trabalho foi realizada a caracterização da pluviosidade através dos dados pluviométricos de 60 postos no período de 1976 a 2001. Foram calculadas as médias mensais, sazonais e anuais e os totais anuais para toda série histórica. Para alguns anos considerados atípicos (secos e chuvosos) foram calculados os desvios-padrão em relação à média. A segunda etapa do trabalho consistiu na aplicação da análise rítmica para os anos eleitos como padrão - 1998 (chuvoso), 1999 (seco) e 2001 (habitual) para Guarapuava e Maringá. Como resultado, constatou-se que a distribuição espacial da pluviosidade, para todas as escalas de análise, apresentou um padrão com os valores mais elevados a montante, devido ao efeito orográfico e ao clima subtropical predominante nessa porção, enquanto os menores valores foram observados a jusante, por estar ela numa área de clima tropical e baixas altitudes. No que se refere à análise rítmica, foi constatado, no ano de 1998, que os maiores valores precipitados sob atuação dos sistemas frontais ocorreram no outono para Guarapuava e no inverno para Maringá, e que somente a frente polar atlântica gerou 57% da pluviosidade para cada localidade em relação ao total anual. Para o ano de 1999 os sistemas frontais geraram valores pluviométricos semelhantes tanto no verão quanto na primavera, para Guarapuava e Maringá... / This research analyzes both the climate dynamics and the rainfall variability. It is aimed to determine the dominant rainfall pattern at different scales of analysis, to define the atmospheric systems and how they influence the rainfall generation. This research was performed according to the rhythm analysis methodology proposed by Monteiro (1971). The Ivaí River Basin drains an area of 35.845 kmø. It is the second largest river basin in the Paraná State. The first step of this research was to characterize rainfall regime based on 60 different rain gauge stations data, collected from 1976 to 2001. This basin monthly, seasonal, yearly averages and yearly totals were calculated based on its historic rainfall records. Atypical years (dry and rainy years) had their standard deviation calculated from mean values. During the second step of this research, rhythm analysis was performed for those years considered atypical - 1998 (rainy), 1999 (dry) and 2001 (typical) both for Guarapuava and Maringá. Each analysis scale showed that rainfall spatial distribution has a pattern of higher levels in the upstream basin. This is true because of the dominant subtropical climate and the orographic effects occurring in this area. Lower values occurred in the downstream basin because of the low altitude and its tropical climate. As far as rhythm analysis is concerned, it was evident that rainfall higher values under frontal systems occurred during the fall of 1998 in Guarapuava city and during the winter time in Maringá city, and also that the Atlantic polar front was responsible for 57% of rainfall measures for each locality in relation to the yearly total. In 1999, frontal systems values were similar in the summer and in the spring time, both in Guarapuava and in Maringá... (Complete abstract click electronic access below)
119

Zoneamento (geo)ambiental analítico da microbacia do Córrego do Rosário (Descalvado, SP) / Analytical (geo)environmental zoning of the Rosário stream microbasin (Descalvado, SP, Brazil)

Inêz, Eliezer Bernardes 24 August 2012 (has links)
Made available in DSpace on 2016-06-02T20:00:46Z (GMT). No. of bitstreams: 1 4666.pdf: 23053590 bytes, checksum: ce37f4ca178bda1c44da5bfda65fc000 (MD5) Previous issue date: 2012-08-24 / Adopting a river basin as a landscape management unit constitutes a major achievement in planning and management due to socio-environmental interactions and their unfoldings that take place in this area. Among the variety of environmental planning and management tools used in river basin contexts, (geo)environmental zoning is noteworthy in that it helps decision makers and aims at reconciling socio-economic development with environmental quality. Along these lines, the purpose of this study focused on the microbasin of the Rosário stream in Descalvado, SP, Brazil was to present an analytical (geo)environmental zoning proposal generated from a set of thematic mapping documents at a 1:10000 scale, field studies, and geo-technologies that seeks to analyze capacities and susceptibilities of this microbasin terrain in the face of urban occupation. Thus, the findings of this study can serve as a basis for discussion and construction of public policies capable of guiding a right and proper local urban expansion process. / A adoção da bacia hidrográfica como unidade de gerenciamento da paisagem constitui um avanço significativo nas atividades de planejamento e gestão, pois nesta área ocorrem interações sócio-ambientais e seus desdobramentos. Dentre os diversos instrumentos de planejamento e gestão ambiental, utilizados no contexto da bacia hidrográfica, merece destaque os zoneamentos (geo)ambientais, pois estes auxiliam os tomadores decisão e buscam compatibilizar o desenvolvimento sócio-econômico com a qualidade ambiental. Nesse contexto, o presente trabalho, que tem como área de estudo a microbacia do córrego do Rosário (Descalvado, SP), apresenta uma proposta de zoneamento (geo)ambiental analítico, gerado a partir de um conjunto de documentos cartográficos temáticos na escala de 1:10.000, trabalhos de campo e de geotecnologias, onde se busca analisar as aptidões e suscetibilidades do terreno da microbacia, frente ao processo de ocupação urbana. Sendo assim, os resultados encontrados podem servir como base para o debate e formulação de políticas públicas municipais capazes de orientar um adequado processo de expansão urbana.
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Cenozoic mafic to intermediate volcanism at Lava Mountain and Spring Mountain, Upper Wind River Basin, Wyoming

Downey, Anna Catherine January 1900 (has links)
Master of Science / Geology / Matthew E. Brueseke / The Upper Wind River Basin (UWRB) is located in north-central Wyoming, to the south of the Yellowstone National Park boundary and east of Jackson Hole. Both Lava Mountain and Spring Mountain are Quaternary volcanoes in the UWRB. Lava Mountain is a shield volcano composed of 26 separate lavas capped by a scoria cone. Spring Mountain is located about ~36 km east of Lava Mountain, north of Dubois, WY, where eruptions of basalt cut through Paleocene and Eocene strata. The goal of this study aims to reconstruct the petrogenesis of magmas erupted at both volcanoes using geochemical, petrographic, and isotopic analyses. Important local events in geologic history played a large role in the development of the UWRB. This includes a long history of ancient and Cenozoic subduction, regional extension, and also the migration of the North American plate over the Yellowstone hotspot. The few previous studies on Lava Mountain claim the rocks are mafic in composition, however this was based solely on reconnaissance geological mapping. Geochemical evidence presented in this thesis show Lava Mountain rocks range from basaltic andesite to dacite. Basaltic andesite and dacite are interstratified at the base until approximately 2774 m; the rest of the volcano is andesite. All Lava Mountain samples are largely aphanitic and crystal-poor. Conversely, at Spring Mountain, localized normal faulting controls the location of eruptions of olivine-rich basalt. Petrographic analysis for both Lava Mountain and Spring Mountain display a range of evidence for open system processes, including sieved and/or resorbed pyroxenes, olivines and feldspars, as well as xenocrysts that suggest an influence from crustal assimilation. A petrogenetic model is introduced that discusses how Lava Mountain magma production occurred via fractional crystallization of basalt to dacite, then magma mixing of basaltic andesite and dacite, coupled with small amounts of crustal assimilation, to form the locally erupted andesites. All samples, including Spring Mountain basalts, have ⁸⁷Sr/⁸⁶Sr isotopes of 0.70608 and 0.70751, with ¹⁴³Nd/¹⁴⁴Nd isotopes of 0.51149 and 0.51157 and εNd values of -18 to -22. Pb isotopes plot to the left of the Geochron and directly on to slightly above the Stacey-Kramers curve. Strontium, neodymium, and lead isotope data suggest that Spring Mountain basalts are melts of ancient (e.g., 2.8 Ga Beartooth province) lithospheric mantle. The high ⁸⁷Sr/⁸⁶Sr values and exceptionally low εNd values separate the UWRB rocks from both Yellowstone and Snake River Plain volcanics, and suggest they originated from a different magma source. Finally, thermal evidence suggests melting genesis for UWRB rocks may not be Yellowstone plume related; rather it is more likely linked to Cenozoic extension.

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