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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.
1

Metal migration from coastal and estuarine landfills : an integrated geological study from southern England

Njue, Cyprian January 2010 (has links)
Uncontrolled landfills can cause the release of significant contamination. In South England and in other parts of the UK, historical landfills are spread along the coastal and estuarine marshes and mudflats, where waste was dumped without regard to the environment. Much of the pollution from these landfills may have been dispersed and diluted into coastal waters with little impact. However, fine-grained sediments within these environments may have trapped or sequestered metals. The aim of this study is to investigate the degree to which heavy metals from these historical sites may have contaminated the adjacent marshes and intertidal mudflats.
2

Modelisation of the diffusive transport of algal blooms in a coastal environment using a stochastic method / Modélisation du transport diffusif des algues en milieu côtier par une méthode stochastique

Joly, Antoine 14 December 2011 (has links)
Ce mémoire de thèse a pour but de présenter un modèle de prédiction du transport des algues en mer le long des côtes. La méthode choisie a été d'utiliser un code industriel eulérien pour prédire l'écoulement moyen sur une grande surface, et d'ensuite ajouter un modèle lagrangien pour prédire le mouvement des particules individuelles. Ce modèle lagrangien comporte trois étapes. Premièrement, les caractéristiques moyennes du fluide trouvées avec le modèle eulérien sont utilisées pour alimenter un modèle stochastique pour trouver les vitesses turbulentes du fluide à l'emplacement des particules modélisant les algues. Ensuite ces vitesses turbulentes sont utilisées à travers les composantes de la force de traînée, de l'inertie, de la force de Basset et de la poussée d'Archimède pour trouver les vitesses des corps. La dernière étape consiste à utiliser ces vitesses des corps pour calculer leurs trajectoires. Une méthode avec un intégrateur exact a été développée pour résoudre ces équations. Ce modèle a ensuite été validé grâce à deux expériences. Dans la première expérience, des sphères de tailles différentes ont été lâchées dans deux fluides avec des densités différentes, où une turbulence stationnaire quasi-homogène a été générée en utilisant une paire de grilles oscillantes. Dans la deuxième expérience des particules sphériques ont été lâchées dans un écoulement non homogène. Cet écoulement a été obtenu en obstruant partiellement un canal, afin qu'une zone de recirculation soit générée. Le modèle de transport des particules a ensuite été testé sur des simulations d'un écoulement réel le long des côtes normandes, dans lequel des particules numériques représentant des algues ont été lâchées / The aim of this PhD thesis was to develop a model to predict the motion of algae in sea waters along a coastline. The method chosen was to use a large Eulerian industrial code to model the mean flow, and add Lagrangian model to predict the motion of individual particles. This Lagrangian modelis a three-step model. In the first modelling step, the mean flow characteristics at the location of the particles (solid bodies modelling the algae) are extracted from the Eulerian model and imputed into a stochastic model to find the turbulent fluid velocities. These fluid velocities are used in the second step to solve for the solid body velocities, by solving for the drag, momentum, buoyant and Basset history forces. The final modelling step is to use these solid body velocities to calculate the trajectories of particles. An exact integrator method was then developed to solve for these equations. The model was then validated using two experiments. Firstly sphere of different size were released in fluids of different densities, where a stationary quasi-homogeneous turbulence. This turbulence was generated by oscillating a pair of grids. In the second experiment spherical particles were released in anon-homogeneous turbulent flow. This flow was achieved by partially obstructing a channel, so that a recirculation zone was generated. The particle transport model was then tested numerically using the simulations of a real flow along the coasts of Normandy where numerical particles representing algae were released
3

Influência das mudanças climáticas em geoindicadores na costa sul do Brasil

Schossler, Venisse January 2016 (has links)
Esta tese investiga se eventos anômalos de precipitação pluviométrica (PP) na Planície Costeira do Rio Grande do Sul (PCRGS) estão relacionados a modos de variabilidade climática e como essa relação pode afetar o ambiente costeiro. A PP e suas anomalias foram estatisticamente correlacionadas aos modos de variabilidade climática, o Modo Anular do Hemisfério Sul (SAM) e El Niño - Oscilação Sul (ENOS). O índice do ENOS utilizado foi o Multivariate ENSO Index (MEI) e do SAM foi o de Nan e Li (2003). Para o cálculo das anomalias de PP foram utilizados dados do satélite Tropical Rainfall Measurement Mission, entre 1998 e 2013. As correlações foram calculadas por meio de matrizes de classificação, e suas significâncias pelo teste-t de Student. A área de estudo foi dividida em costas sul (33°44’39” – 32°09’36”S), central (32°09’36” – 30°10’12”S) e norte (30°10’12” – 29°19’34”S) e para cada uma delas foi escolhido um geoindicador (sangradouros ou lagunas), examinados em imagens de satélite. Comparouse os geoindicadores em períodos de PP anomalamente positiva e negativa. Para destacar as variações nos geoindicadores foram utilizadas composições RGB 543 dos sensores Thematic Mapper (TM) e Enhanced Thematic Mapper Plus (ETM+) do Landsat. Os resultados apontam para correlação negativa entre as anomalias de PP nas costas sul e central com o SAM e correlação positiva das anomalias de PP da costa sul com o MEI. A PP na costa norte não apresenta correlação com nenhum dos dois índices. Foram identificados 28 eventos anômalos de PP no período 1998-2013. Nas imagens de satélite todos geoindicadores apontaram para variações morfológicas e hídricas entre os períodos PP acima e abaixo da média, sendo a costa norte a que apresenta menor variação visível. A costa sul tem a menor média de PP e o maior número de eventos anômalos de PP, dos quais 67% eram de PP negativa. A maioria dos eventos são de PP negativa (78%) e podem estar relacionados simultaneamente ao SAM positivo e MEI negativo, ou somente ao MEI positivo. Todos eventos de PP positiva foram concomitantes ao MEI positivo. As costas sul e central mostram uma redução na PP média. Essa tendência pode estar relacionada as mudanças climáticas globais, pela intensificação do SAM positivo e de eventos El Niño e La Niña. As variações observadas nos geoindicadores (sangradouros ou lagunas) indicam que a redução na PP média resulta em menor volume de sedimentos transportados do pós praia para a zona de arrebentação e face praial, alterando o balanço sedimentar. As areias secas dos campos de dunas transportadas pelo vento podem assorear lagos e lagunas da área de estudo, desequilibrando o ecossistema. / This thesis investigates whether anomalous events of precipitation (PP) in the Coastal Plain of Rio Grande do Sul (RGSCP) are related to climate variability modes and how this relationship can affect the coastal environment. The PP and its anomalies were statistically correlated to climate variability modes, the Southern Annular Mode (SAM) and El Niño-Southern Oscillation (ENSO). The used ENSO index was the Multivariate ENSO Index (MEI) and SAM is the one defined by Nan and Li (2003). For the calculation of the PP anomalies, we used data from the Tropical Rainfall Measurement Mission satellite, from 1998 to 2013. Correlations were calculated using classification matrices, and their significance by the the Student t-test. The study area was divided into south (33°44'39" – 32°09'36"S), central (32°09'36"– 30°10'12"S) and north (30°10'12"– 29°19'34"S) coasts and for each one it was chosen a geoindicador (washouts or lagoons), examined on satellite images. This investigation compared the geoindicators in positive and negative anomalous PP periods. To highlight variations in the geoindicators, it was used the RGB 543 composition of the Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) Landsat sensors. The results point to a negative correlation of the PP anomalies in the southern and central coasts with the SAM and a positive correlation of PP anomalies in the south coast with the MEI. The north coast PP is not correlated with any of the two indexes. Twenty-eight anomalous PP events were found in the 1988–2013 period. In satellite images, all geoindicators pointed to morphological and hydrological variations between periods of PP above and below the mean, the northern coast has the least visible variations. The south coast has the lowest mean PP and the largest number of anomalous events, of which 67% were negative PP. The majority of events are negative PP (78%), they could be simultaneously connected to a positive SAM and a negative MEI, or only to a positive MEI. All positive PP events were concomitant to a positive MEI. The central and southern coasts show a decrease in the men PP. This trend may be related to global climate change, by the intensification of the positive SAM and of El Niño and La Niña events. The variations observed in geoindicators (washouts or lagoons) indicate that the reduction in the mean PP results in lower volume of sediments transported from the backshore to the surf zone and the shoreface, changing the sedimentary balance. The dry sands from the wind-transported dune fields could silt up lakes and lagoons of the study area, unbalancing the ecosystem.
4

Modelisation of the diffusive transport of algal blooms in a coastal environment using a stochastic method

Joly, Antoine 14 December 2011 (has links) (PDF)
The aim of this PhD thesis was to develop a model to predict the motion of algae in sea waters along a coastline. The method chosen was to use a large Eulerian industrial code to model the mean flow, and add Lagrangian model to predict the motion of individual particles. This Lagrangian modelis a three-step model. In the first modelling step, the mean flow characteristics at the location of the particles (solid bodies modelling the algae) are extracted from the Eulerian model and imputed into a stochastic model to find the turbulent fluid velocities. These fluid velocities are used in the second step to solve for the solid body velocities, by solving for the drag, momentum, buoyant and Basset history forces. The final modelling step is to use these solid body velocities to calculate the trajectories of particles. An exact integrator method was then developed to solve for these equations. The model was then validated using two experiments. Firstly sphere of different size were released in fluids of different densities, where a stationary quasi-homogeneous turbulence. This turbulence was generated by oscillating a pair of grids. In the second experiment spherical particles were released in anon-homogeneous turbulent flow. This flow was achieved by partially obstructing a channel, so that a recirculation zone was generated. The particle transport model was then tested numerically using the simulations of a real flow along the coasts of Normandy where numerical particles representing algae were released
5

Influência das mudanças climáticas em geoindicadores na costa sul do Brasil

Schossler, Venisse January 2016 (has links)
Esta tese investiga se eventos anômalos de precipitação pluviométrica (PP) na Planície Costeira do Rio Grande do Sul (PCRGS) estão relacionados a modos de variabilidade climática e como essa relação pode afetar o ambiente costeiro. A PP e suas anomalias foram estatisticamente correlacionadas aos modos de variabilidade climática, o Modo Anular do Hemisfério Sul (SAM) e El Niño - Oscilação Sul (ENOS). O índice do ENOS utilizado foi o Multivariate ENSO Index (MEI) e do SAM foi o de Nan e Li (2003). Para o cálculo das anomalias de PP foram utilizados dados do satélite Tropical Rainfall Measurement Mission, entre 1998 e 2013. As correlações foram calculadas por meio de matrizes de classificação, e suas significâncias pelo teste-t de Student. A área de estudo foi dividida em costas sul (33°44’39” – 32°09’36”S), central (32°09’36” – 30°10’12”S) e norte (30°10’12” – 29°19’34”S) e para cada uma delas foi escolhido um geoindicador (sangradouros ou lagunas), examinados em imagens de satélite. Comparouse os geoindicadores em períodos de PP anomalamente positiva e negativa. Para destacar as variações nos geoindicadores foram utilizadas composições RGB 543 dos sensores Thematic Mapper (TM) e Enhanced Thematic Mapper Plus (ETM+) do Landsat. Os resultados apontam para correlação negativa entre as anomalias de PP nas costas sul e central com o SAM e correlação positiva das anomalias de PP da costa sul com o MEI. A PP na costa norte não apresenta correlação com nenhum dos dois índices. Foram identificados 28 eventos anômalos de PP no período 1998-2013. Nas imagens de satélite todos geoindicadores apontaram para variações morfológicas e hídricas entre os períodos PP acima e abaixo da média, sendo a costa norte a que apresenta menor variação visível. A costa sul tem a menor média de PP e o maior número de eventos anômalos de PP, dos quais 67% eram de PP negativa. A maioria dos eventos são de PP negativa (78%) e podem estar relacionados simultaneamente ao SAM positivo e MEI negativo, ou somente ao MEI positivo. Todos eventos de PP positiva foram concomitantes ao MEI positivo. As costas sul e central mostram uma redução na PP média. Essa tendência pode estar relacionada as mudanças climáticas globais, pela intensificação do SAM positivo e de eventos El Niño e La Niña. As variações observadas nos geoindicadores (sangradouros ou lagunas) indicam que a redução na PP média resulta em menor volume de sedimentos transportados do pós praia para a zona de arrebentação e face praial, alterando o balanço sedimentar. As areias secas dos campos de dunas transportadas pelo vento podem assorear lagos e lagunas da área de estudo, desequilibrando o ecossistema. / This thesis investigates whether anomalous events of precipitation (PP) in the Coastal Plain of Rio Grande do Sul (RGSCP) are related to climate variability modes and how this relationship can affect the coastal environment. The PP and its anomalies were statistically correlated to climate variability modes, the Southern Annular Mode (SAM) and El Niño-Southern Oscillation (ENSO). The used ENSO index was the Multivariate ENSO Index (MEI) and SAM is the one defined by Nan and Li (2003). For the calculation of the PP anomalies, we used data from the Tropical Rainfall Measurement Mission satellite, from 1998 to 2013. Correlations were calculated using classification matrices, and their significance by the the Student t-test. The study area was divided into south (33°44'39" – 32°09'36"S), central (32°09'36"– 30°10'12"S) and north (30°10'12"– 29°19'34"S) coasts and for each one it was chosen a geoindicador (washouts or lagoons), examined on satellite images. This investigation compared the geoindicators in positive and negative anomalous PP periods. To highlight variations in the geoindicators, it was used the RGB 543 composition of the Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) Landsat sensors. The results point to a negative correlation of the PP anomalies in the southern and central coasts with the SAM and a positive correlation of PP anomalies in the south coast with the MEI. The north coast PP is not correlated with any of the two indexes. Twenty-eight anomalous PP events were found in the 1988–2013 period. In satellite images, all geoindicators pointed to morphological and hydrological variations between periods of PP above and below the mean, the northern coast has the least visible variations. The south coast has the lowest mean PP and the largest number of anomalous events, of which 67% were negative PP. The majority of events are negative PP (78%), they could be simultaneously connected to a positive SAM and a negative MEI, or only to a positive MEI. All positive PP events were concomitant to a positive MEI. The central and southern coasts show a decrease in the men PP. This trend may be related to global climate change, by the intensification of the positive SAM and of El Niño and La Niña events. The variations observed in geoindicators (washouts or lagoons) indicate that the reduction in the mean PP results in lower volume of sediments transported from the backshore to the surf zone and the shoreface, changing the sedimentary balance. The dry sands from the wind-transported dune fields could silt up lakes and lagoons of the study area, unbalancing the ecosystem.
6

Influência das mudanças climáticas em geoindicadores na costa sul do Brasil

Schossler, Venisse January 2016 (has links)
Esta tese investiga se eventos anômalos de precipitação pluviométrica (PP) na Planície Costeira do Rio Grande do Sul (PCRGS) estão relacionados a modos de variabilidade climática e como essa relação pode afetar o ambiente costeiro. A PP e suas anomalias foram estatisticamente correlacionadas aos modos de variabilidade climática, o Modo Anular do Hemisfério Sul (SAM) e El Niño - Oscilação Sul (ENOS). O índice do ENOS utilizado foi o Multivariate ENSO Index (MEI) e do SAM foi o de Nan e Li (2003). Para o cálculo das anomalias de PP foram utilizados dados do satélite Tropical Rainfall Measurement Mission, entre 1998 e 2013. As correlações foram calculadas por meio de matrizes de classificação, e suas significâncias pelo teste-t de Student. A área de estudo foi dividida em costas sul (33°44’39” – 32°09’36”S), central (32°09’36” – 30°10’12”S) e norte (30°10’12” – 29°19’34”S) e para cada uma delas foi escolhido um geoindicador (sangradouros ou lagunas), examinados em imagens de satélite. Comparouse os geoindicadores em períodos de PP anomalamente positiva e negativa. Para destacar as variações nos geoindicadores foram utilizadas composições RGB 543 dos sensores Thematic Mapper (TM) e Enhanced Thematic Mapper Plus (ETM+) do Landsat. Os resultados apontam para correlação negativa entre as anomalias de PP nas costas sul e central com o SAM e correlação positiva das anomalias de PP da costa sul com o MEI. A PP na costa norte não apresenta correlação com nenhum dos dois índices. Foram identificados 28 eventos anômalos de PP no período 1998-2013. Nas imagens de satélite todos geoindicadores apontaram para variações morfológicas e hídricas entre os períodos PP acima e abaixo da média, sendo a costa norte a que apresenta menor variação visível. A costa sul tem a menor média de PP e o maior número de eventos anômalos de PP, dos quais 67% eram de PP negativa. A maioria dos eventos são de PP negativa (78%) e podem estar relacionados simultaneamente ao SAM positivo e MEI negativo, ou somente ao MEI positivo. Todos eventos de PP positiva foram concomitantes ao MEI positivo. As costas sul e central mostram uma redução na PP média. Essa tendência pode estar relacionada as mudanças climáticas globais, pela intensificação do SAM positivo e de eventos El Niño e La Niña. As variações observadas nos geoindicadores (sangradouros ou lagunas) indicam que a redução na PP média resulta em menor volume de sedimentos transportados do pós praia para a zona de arrebentação e face praial, alterando o balanço sedimentar. As areias secas dos campos de dunas transportadas pelo vento podem assorear lagos e lagunas da área de estudo, desequilibrando o ecossistema. / This thesis investigates whether anomalous events of precipitation (PP) in the Coastal Plain of Rio Grande do Sul (RGSCP) are related to climate variability modes and how this relationship can affect the coastal environment. The PP and its anomalies were statistically correlated to climate variability modes, the Southern Annular Mode (SAM) and El Niño-Southern Oscillation (ENSO). The used ENSO index was the Multivariate ENSO Index (MEI) and SAM is the one defined by Nan and Li (2003). For the calculation of the PP anomalies, we used data from the Tropical Rainfall Measurement Mission satellite, from 1998 to 2013. Correlations were calculated using classification matrices, and their significance by the the Student t-test. The study area was divided into south (33°44'39" – 32°09'36"S), central (32°09'36"– 30°10'12"S) and north (30°10'12"– 29°19'34"S) coasts and for each one it was chosen a geoindicador (washouts or lagoons), examined on satellite images. This investigation compared the geoindicators in positive and negative anomalous PP periods. To highlight variations in the geoindicators, it was used the RGB 543 composition of the Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) Landsat sensors. The results point to a negative correlation of the PP anomalies in the southern and central coasts with the SAM and a positive correlation of PP anomalies in the south coast with the MEI. The north coast PP is not correlated with any of the two indexes. Twenty-eight anomalous PP events were found in the 1988–2013 period. In satellite images, all geoindicators pointed to morphological and hydrological variations between periods of PP above and below the mean, the northern coast has the least visible variations. The south coast has the lowest mean PP and the largest number of anomalous events, of which 67% were negative PP. The majority of events are negative PP (78%), they could be simultaneously connected to a positive SAM and a negative MEI, or only to a positive MEI. All positive PP events were concomitant to a positive MEI. The central and southern coasts show a decrease in the men PP. This trend may be related to global climate change, by the intensification of the positive SAM and of El Niño and La Niña events. The variations observed in geoindicators (washouts or lagoons) indicate that the reduction in the mean PP results in lower volume of sediments transported from the backshore to the surf zone and the shoreface, changing the sedimentary balance. The dry sands from the wind-transported dune fields could silt up lakes and lagoons of the study area, unbalancing the ecosystem.
7

Os primeiros estágios de vida da savelha (Brevoortia pectinata) no estuário da Lagoa dos Patos

Malanski, Evandro January 2011 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2011. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-10-09T17:25:09Z No. of bitstreams: 1 Evandro.pdf: 2513898 bytes, checksum: 56564f2ddd5a85095a4f342776ac7ec9 (MD5) / Approved for entry into archive by Sabrina Andrade (sabrinabeatriz@ibest.com.br) on 2013-10-17T03:06:55Z (GMT) No. of bitstreams: 1 Evandro.pdf: 2513898 bytes, checksum: 56564f2ddd5a85095a4f342776ac7ec9 (MD5) / Made available in DSpace on 2013-10-17T03:06:55Z (GMT). No. of bitstreams: 1 Evandro.pdf: 2513898 bytes, checksum: 56564f2ddd5a85095a4f342776ac7ec9 (MD5) Previous issue date: 2011 / Os padrões associados às condições ambientais e a distribuição espaço-temporal dos estágios iniciais da savelha, B. pectinata, e de seu desenvolvimento no estuário da Lagoa dos Patos foram investigados através de dados históricos. Dois outros experimentos complementares foram realizados: um para avaliar as técnicas de medição (tradicional e por imagem) em larvas de peixes; e, outro, para investigar o efeito dos principais conservantes (álcool 70 % e formaldeído 3,6%) sobre as larvas de savelha. Diferença significativa na medição de larvas de peixes entre ambas as técnicas não foi observada, e os coeficientes de variação foram similares, o que sugere que as técnicas produzem o mesmo resultado médio, apesar do ganho de precisão pela técnica de análise por imagem. Um encolhimento significativo foi observado para ambos os conservantes, e os fatores de correção para as larvas de B. pectinata em formaldeído foi CP vivo = 1,0799 × CP pós-conservação, e em álcool foi CP vivo = 1,1415×CP pós-conservação. No período de 1975 a 2009, um total de 10479 ovos e 14066 larvas e juvenis foram coletados através de amostragens planctônicas, e também amostrados parâmetros da água (salinidade e temperatura). As larvas foram medidas e classificadas de acordo com seu estágio de desenvolvimento. Cada estágio de desenvolvimento foi caracterizado pelo seu intervalo de tamanho, onde a menor larva em estágio vitelínico mediu 2,16 mm, e o maior juvenil teve 43,25 mm. As análises dos padrões de distribuição indicam desova fora da Lagoa dos Patos, em salinidade mais elevada, sendo importantes períodos sazonais para os ovos o inverno, primavera e início de verão, e posteriormente ocorre um transporte para dentro da região estuarina nos estágios mais iniciais de desenvolvimento, associados a valores menores de salinidade e temperatura. A distribuição dos juvenis indicou um retorno para a região costeira, e neste estágio o outono foi um período muito importante. Estes resultados são importantes para o conhecimento desta espécie, e serão úteis para o planejamento no gerenciamento deste recurso. / Patterns associated to environmental conditions and to the spatial and temporal distributions of the early stages of Argentine menhaden, B. pectinata, and of its development in the Patos Lagoon estuary were investigated using historical records. Two other complementary experiments were performed: one to evaluate the measurement techniques (traditional and image) in larval fishes; and, other, to investigate the effect of main conservatives (alcohol 70 % and formaldehyde 3.6 %) over Argentine menhaden larvae. Significant difference in the measurement of fish larvae between techniques was not observed, and the coefficients of variation were similar, suggesting that these two techniques produce the same average result, despite the gain in precision by image analysis technique. A significant shrinkage was observed for both preservatives, and the correction factors for B. pectinata larvae in formaldehyde was SL live= 1.0799 × SL post-conservation, and in alcohol was SL live= 1.1415 × SL post-conservation. From 1975 to 2009 a total of 10479 eggs and 14066 fish larvae and juveniles were collected at plankton surveys, and sampled water parameters (salinity and temperature), too. Larvae were measured and classified according to their developmental stage. Each development stage was characterized by its size range, which the smallest yolk-sac larvae measured 2.16 mm, and the largest juveniles had 43.25 mm. Analysis of the distributional pattern indicate spawning outside the Patos Lagoon, in high salinities, being important seasonal period for the eggs the winter, spring and early summer, and after occur a transport to the inner estuarine region in the earlier developmental stages, associated to lesser temperature and salinity values. Distribution of juveniles indicated a return to the coastal region, and in this stage the autumn was a very important period. These results are important for knowledge this specie, and will be useful for planning the management of this resource.
8

Sustainable Beach Resort Development: A Decision Framework for Coastal Resort Development in Egypt and the United States

Aly Ahmed, Bakr Mourad 18 January 2002 (has links)
In recent decades, coastal tourism has grown significantly bringing enormous economic benefits to host communities, and causing many environmental and social impacts to the coastal environment. Beach resort development faces problems due to an inability on the part of stakeholders to make sound decisions about sustainable design due, in part, to the complexity of the sustainability issues and the lack of a comprehensive decision-making tool to assist them. In Egypt, design and planning regulations have not changed for decades, resulting in non-sustainable beach resort development. This study provides a "decision framework," a conceptual "Sustainable Design Model," which shifts the focus of stakeholders from the application of traditional physical carrying capacity procedures to a comprehensive approach linking sustainability indicators and carrying capacities. This approach includes an array of acceptable capacities based on the ecological, social, psychological, physical, economic, and managerial capacity thresholds of a site. This framework assists stakeholders in making rational decisions about what is to be built, where it is located, and how to build it. To test the model, a survey was conducted at 10 beach resort destinations (5 American, 5 Egyptian) to measure the difference in perceptions between stakeholders concerning sustainability indicators and carrying capacities. The instrument was determined valid and reliable using a test/retest procedure. A total of 276 responses were obtained for data analysis. Statistical analyses included frequency distribution, t-tests, analysis of variance (ANOVA), factor analysis, and a stepwise multiple regression analysis. Sample demographic information was also collected. Results revealed a strong link between sustainability indicators and carrying capacity thresholds. While both Egyptian and American respondents recognized the importance of sensitive environmental developments, there were significant differences due to differences in culture, environment, regulations, and priorities. The American sample placed greater importance on the ecological indicators, while the Egyptian sample placed greater importance on the social, psychological, and managerial indicators. The American sample conveyed a positive attitude toward government regulations, design, and management efforts to incorporate sustainability principles into the built environment, while the Egyptian respondents conveyed a more negative attitude. As a result of this study, future Egyptian policy may be better informed of the gap between the theoretical concepts of sustainability and real world coastal development implementation. / Ph. D.
9

Percepção ambiental de professores em ecossistemas costeiros: influência de uma vivência formativa do Projeto Trilha Subaquática / Environmental perception of teachers in coastal ecosystems: influence of training experience of Underwater Trail Project

Katon, Geisly França 16 December 2015 (has links)
Grande parte das ameaças à biodiversidade dos ambientes marinhos e costeiros é resultado direto da população humana e das tendências de aumento demográfico. Uma das dificuldades para a proteção dos ambientes naturais está na existência de diferenças nas percepções dos valores e importância dos mesmos entre os indivíduos de culturas diferentes ou de diferentes grupos. Consideramos que uma importante etapa para a conservação da biodiversidade é entender a Percepção Ambiental dos sujeitos que compõe a população local. Entendemos como Percepção Ambiental a relação que indivíduo estabelece com o meio no qual está inserido, que ocorre através de mecanismos perceptivos e cognitivos. O presente trabalho visa contribuir na ampliação do conhecimento de tal temática, principalmente enfocando Ambientes Marinhos e Costeiros. Para isso, investigamos a Percepção Ambiental de um grupo de professores de uma escola pública do litoral norte de São Paulo (Ubatuba, SP) que participaram de uma vivência formativa em atividades de Educação Ambiental. Este trabalho apresenta como objetivos específicos: 1) verificar se e como a participação nas atividades educacionais influenciou a Percepção Ambiental de tais professores; 2) investigar as concepções que os professores apresentam sobre as possibilidades e desafios da prática docente ao abordar o ambiente marinho e costeiro a partir dos subsídios fornecidos pela vivência formativa. Os professores participaram das atividades do Projeto Trilha Subaquática que foram desenvolvidas ao longo de dois dias no Parque Estadual da Serra do Mar e no Parque Estadual Ilha Anchieta, ambos em Ubatuba, São Paulo. Utilizamos instrumentos de coleta de dados que foram aplicados tanto no início quanto no final da vivência (questionário e redação), além do registro audiovisual referente às Reflexões Coletivas realizadas ao final de cada dia. A partir da análise dos dados coletados, que foi feita por categorização aberta e por análise de conteúdo categorial, foi possível notar que participar das atividades de Educação Ambiental influenciou, em alguns aspectos a Percepção Ambiental dos professores. Tal influência ficou mais evidente em aspectos específicos, como, por exemplo, em relação à biodiversidade destes ambientes. Ainda que a percepção dos professores em relação a causarem impactos ao ambiente durante a realização das atividades não tenha sido expressa por todos, quando tais impactos foram percebidos, estavam bastante relacionados aos organismos do costão rochoso, especificamente ao pisoteio dos mesmos. Verificamos ainda aspectos interessantes sobre as representações sociais desses sujeitos que, apesar da participação na vivência, continua sendo majoritariamente antropocêntrica. Sobre as possibilidades e desafios da prática docente ao abordar os ambientes marinhos e costeiros, pudemos notar que para os professores sujeitos desta pesquisa, as atividades de campo são as mais significativas para se trabalhar tal tema. Além disso, pudemos notar a grande importância que a troca de experiências entre os pares, como os proporcionados pela vivência, apresentam na composição das práticas docentes. / Much of the threats to marine and coastal biodiversity are directly result of human population and tendency of demographic increase. One of the difficulties to protect natural environments relies in the differences in perceptions of the values and importance of those between individuals of different cultures or different groups. We consider that understand Environmental Perception from local population is an important step for biodiversity conservation. We understand as Environmental Perception the relation that people establish with the environment in which it is inserted, that occurs through perceptual and cognitive mechanisms. The aim of this work is contribute to expansion of the knowledge about the concept, mainly focusing in Marine Environment e Coastal Environment. For that, we investigated the Environmental Perception of a group of teachers from a public school in north coast of São Paulo State (Ubatuba) who participated in a formative experience in Environmental Education activities. This work presents as specifics goals: 1) verify whether and how the participation in educational activities influenced the environmental perception of such teachers; 2) investigate the conceptions that teachers have about the possibilities and challenges of teaching practice in addressing marine and coastal environment from the subsidies provided by the training experience. The teachers participated of Underwater Trail Project activities that are developed along two days in Serra do Mar State Park and in Ilha Anchieta State Park, both in Ubatuba, São Paulo State. We use data collection instruments which were applied at the beginning and at the end of the experience (a questionnaire and a composition), besides the transcripts of the audiovisual material related to Collective Reflections made at the end of each day. From the analysis of the data collected, it was done by open categorization and categorical content analysis, it was noticeable that participate in environmental education activities influenced, even subtly, teacher\'s Environmental Perception. This effect was more evident in specific aspects, such as, for example, in relation to biodiversity of these environments. Although the perception of teachers in relation to cause impacts on the environment during the course of the activities it has not been expressed by all, when such impacts were perceived, were closely related to the rocky shore organisms, specifically to trampling them. We also found interesting aspects about the social representations of those guys who, despite participating in the experience, remains largely anthropocentric. About the possibilities and challenges of teaching practice in addressing marine and coastal environments, we noticed that for subject teachers of this research, field activities are the most significant to work with such a theme. In addition, we noted the great importance that the exchange of experiences among peers, as provided by the experience, present in the composition of teaching practices.
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Influ?ncia dos modelos digitais de terreno na modelagem de circula??o hidrodin?mica 2DH: um estudo de caso

Moura, Jos? Edson de 28 December 2010 (has links)
Made available in DSpace on 2014-12-17T15:03:25Z (GMT). No. of bitstreams: 1 JoseEM_DISSERT_1-90.pdf: 4896611 bytes, checksum: 9ac9fa14f37adc67a0417c2b8781cf4e (MD5) Previous issue date: 2010-12-28 / Digital Elevation Models (DEM) are numerical representations of a portion of the earth surface. Among several factors which affect the quality of a DEM, it should be emphasized the attention on the input data and the choice of the interpolating algorithm. On the other hand, several numerical models are used nowadays to characterize nearshore hydrodynamics and morphological changes in coastal areas, whose validation is based on field data collection. Independent on the complexity of the physical processes which are modeled, little attention has been given to the intrinsic bathymetric interpolation built within the numerical models of the specific application. Therefore, this study aims to investigate and to quantify the influence of the bathymetry, as obtained by a DEM, on the hydrodynamic circulation model at a coastal stretch, off the coast of the State of Rio Grande do Norte, Northeast Brazil. This coastal region is characterized by strong hydrodynamic and littoral processes, resulting in a very dynamic morphology with shallow coastal bathymetry. Important economic activities, such as oil exploitation and production, fisheries, salt ponds, shrimp farms and tourism, also bring impacts upon the local ecosystems and influence themselves the local hydrodynamics. This fact makes the region one of the most important for the development of the State, but also enhances the possibility of serious environmental accidents. As a hydrodynamic model, SisBaHiA? - Environmental Hydrodynamics System ( Sistema B?sico de Hidrodin?mica Ambiental ) was chosen, for it has been successfully employed at several locations along the Brazilian coast. This model was developed at the Coastal and Oceanographical Engineering Group of the Ocean Engineering Program at the Federal University of Rio de Janeiro. Several interpolating methods were tested for the construction of the DEM, namely Natural Neighbor, Kriging, Triangulation with Linear Interpolation, Inverse Distance to a Power, Nearest Neighbor, and Minimum Curvature, all implemented within the software Surfer?. The bathymetry which was used as reference for the DEM was obtained from nautical charts provided by the Brazilian Hydrographic Service of the Brazilian Navy and from a field survey conducted in 2005. Changes in flow velocity and free surface elevation were evaluated under three aspects: a spatial vision along three profiles perpendicular to the coast and one profile longitudinal to the coast as shown; a temporal vision from three central nodes of the grid during 30 days; a hodograph analysis of components of speed in U and V, by different tidal cycles. Small, but negligible, variations in sea surface elevation were identified. However, the differences in flow and direction of velocities were significant, depending on the DEM / Os modelos digitais de terreno (MDT) consistem na representa??o matem?tica computacional da distribui??o de um fen?meno espacial que ocorre dentro de uma regi?o da superf?cie terrestre. A qualidade da representa??o do MDT est? influenciada, dentre outros fatores, pela origem do dado e pelo algoritmo interpolador utilizado. A caracteriza??o da circula??o hidrodin?mica ? um dos estudos com apelo ambiental que se utiliza dos MDTs como dado de entrada e, independentemente da complexidade dos processos representados nos modelos num?ricos, pode ter a qualidade de seus resultados dependente da capacidade de reprodu??o do MDT usado para representar a batimetria da ?rea de interesse. Sendo assim, o objetivo deste estudo ? avaliar a influ?ncia de batimetrias obtidas de diversos MDTs, nos padr?es de circula??o hidrodin?mica via modelagem num?rica. Para tanto, considerou-se os dados referentes ? regi?o costeira do nordeste do Brasil, correspondente ao litoral setentrional do estado do Rio Grande do Norte, frontal aos munic?pios de Macau, Guamar? e Galinhos. Essa regi?o se caracteriza pela forte presen?a de processos f?sicos costeiros, com batimetria rasa e complexas fei??es de fundo. A presen?a intensa de atividades petrol?feras faz da regi?o uma das mais importantes para o desenvolvimento socioecon?mico do estado, mas, por outro lado, potencializa a possibilidade de acidentes ambientais de grandes e graves propor??es. O modelo de circula??o hidrodin?mica utilizado foi o 2DH, que faz parte do Sistema de Hidrodin?mica Ambiental, chamado SisBaHiA?, desenvolvido pela ?rea de Engenharia Costeira e Oceanogr?fica do Programa de Engenharia Oce?nica da COPPE/UFRJ. Os interpoladores avaliados foram Vizinho Natural, Krigagem, Triangula??o Irregular Linear, Inverso da Dist?ncia, Vizinho mais Pr?ximo, M?nima Curvatura, Fun??o de Base Radial, Polin?mio Local, Regress?o Polinomial, M?dia M?vel, M?trica de Dados e M?todo de Shepard Modificado, implementados no software comercial Surfer? para a gera??o dos MDTs. Os dados batim?tricos, que serviram como base para a constru??o dos MDTs, s?o oriundos de campanha de campo e de cartas n?uticas. Os resultados das modelagens foram analisados pelas avalia??es dos campos de velocidade e eleva??o, sob tr?s aspectos: uma vis?o espacial dos resultados, atrav?s da an?lise de tr?s perfis perpendiculares ? linha de costa e um perfil transversal ? linha de costa; uma vis?o temporal dos resultados, ao longo do per?odo de 30 dias, a partir de tr?s n?s centrais da malha; e finalmente uma an?lise hodogr?fica das componentes de velocidade em U e V, em diferentes ciclos de mar?s. Foram verificadas varia??es pouco significativas nos campos de eleva??es, podendo as mesmas serem desprezadas, por?m no que diz respeito aos campos de velocidade e dire??es de fluxo, notam-se varia??es associadas aos MDTs utilizados, uma vez que todas as condicionantes hidrodin?micas foram mantidas

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