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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.
121

Dredging and reclamation impact on marine environment in Deep Bay

Poon, Sau-man, Anne., 潘秀文. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
122

Predicted achievement of strategic sewage disposal scheme in enhancement of marine water quality in Hong Kong

Loke, Hing-wa., 陸慶華. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
123

Hong Kong Government criteria for assessing contamination levels of dredged marine sediments

Ma, Kit-cheong, James., 馬傑昌. January 2000 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
124

Hong Kong marine sediment contamination with Tributyltin and its impacts

Tu, Wai-ki, Alex., 杜偉麒. January 2000 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
125

Is reclamation necessary in Victoria Harbour?

Yuen, Ping-shu, Gomez., 袁秉樞. January 2000 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
126

Coastal water quality.

Mardon, David W. January 2003 (has links)
This research focuses on the pathogenic pollution of coastal recreational waters. Pollution of this resource can have serious social and economic implications. The health of the public could be compromised and there may be associated adverse impacts on the tourism industry. A section of coastline along the Durban Bight and including some of the nation's premier bathing beaches, was used for a case study. The water quality condition of the beaches was evaluated against both local and international marine recreational water quality standards. Most of Durban's bathing beaches were found to have good water quality. However beaches situated close to stormwater drains regularly experience poor water quality conditions. The relationships between beach water quality, the pollution sources and environmental factors such as rainfall were quantified. A weak correlation was found between rainfall and beach pathogenic pollution levels. No correlation was found between successive fortnightly beach samples indicating that the time scales of coastal dispersion processes are significantly shorter than the beach monitoring period. The research also indicates a need to update the SA marine water quality standards. The exclusive use of Escherichia coli (E.coli) as the indicator of faecal pollution is inconsistent with international trends towards the use of Enterococcus, which is a more robust pathogen indicator for marine environments. The main aim of the research was to develop a model to predict the water quality conditions of beaches. The Coastal Water Quality Model (CWQM) is intended to serve two functions: firstly to provide daily estimates of pathogenic pollution levels for beach management (e.g. closure under poor water quality conditions), and secondly to provide decision-makers with a tool for predicting the effects of changes on future water quality conditions. The CWQM was formulated as a stochastic state-space lumped advection diffusion model. A Kalman Filter was used for state estimation. Parameter estimation using the Extended Kalman filter was investigated but found to be unsatisfactory due to large input uncertainties and sparse measurements. An alternative statistical fitting procedure was therefore used for parameter estimation. The model was shown to produce accurate predictions of pathogenic pollution for the case study site. To further demonstrate it's utility. it was used to evaluate options for improving the poor water quality at Battery Beach. The results show that a constructed wetland could be effective in this case. / Thesis (M.Sc.)-University of Natal, Natal, 2003.
127

Avaliação da dispersão das plumas dos emissários submarinos no canal de São Sebastião (estado de São Paulo, Brasil), através da modelagem numérica. / Evaluation of the dispersion of plumes of submarine outfall in the São Sebastião channel (state of São Paulo, Brazil), using numerical modeling.

Ferreira, João Paulo Mendes 15 April 2019 (has links)
A região de estudo situa-se no Canal de São Sebastião, Litoral Norte do Estado de São Paulo (Brasil), onde se localizam quatro emissários submarinos situados entre as cidades São Sebastião e Ilhabela. Este canal é utilizado para a prática de diversos esportes náuticos, pesca esportiva e artesanal, sendo a avaliação dos efeitos do despejo de efluentes domésticos e industriais nesse corpo d\'água fundamental para assegurar a qualidade do ambiente e garantir a preservação da saúde humana. O objetivo deste estudo foi avaliar, em meses de verão e inverno de um ano típico, a concentração de potenciais contaminantes (coliformes fecais e nutrientes), em condições extremas, e a dispersão das plumas dos efluentes desses emissários. Para isso, foram utilizados módulos hidrodinâmico e de qualidade de água do modelo Delft3D (para o campo distante), bem como o modelo CORMIX (para o campo próximo). Os resultados das simulações hidrodinâmicas foram consistentes com as características citadas em literatura e a partir de parâmetros estatísticos. A modelagem de campo próximo mostrou a influência das correntes no transporte e diluição inicial das plumas dos efluentes. Após o acoplamento, os resultados das simulações de campo distante da modelagem das plumas dos emissários submarinos mostraram que as mesmas não excederam os níveis máximos estabelecidos pelo CONAMA (Nº 274/2000 e 357/2005) ao atingir a costa. Conforme os resultados de monitoramento in situ realizados pela Companhia Ambiental do Estado de São Paulo, as praias locais próximas aos emissários são geralmente classificadas como impróprias para o banho e com má qualidade da água. Assim, o esgoto bruto despejado através dos córregos ou diretamente nas praias pode ser identificado como o responsável pela contaminação ambiental da costa na área de estudo. / The study region is located in the São Sebastião channel, in the north coast of São Paulo (Brazil), where four submarine outfall are located between São Sebastião and Ilhabela cities. This channel is used for the practice of various nautical sports, sport fishing and crafts, and the evaluation of the effects of the disposal of domestic and industrial effluents in this water body is fundamental to ensure the water quality and the preservation of human health. The objective of this study was to evaluate the concentration of potential contaminants (fecal coliforms and nutrients) during the summer and winter of a typical year, in extreme conditions, and the dispersion of effluent plumes from these submarine outfalls. For that, Delft3D model\'s hydrodynamic and water quality modules (far field) were used, as well as the CORMIX model (near field). Results of hydrodynamic simulations were consistent with the characteristics cited in the literature and from statistical parameters. Near field modeling showed the influence of the currents in the transport and initial dilution of the effluent plumes from the submarine outfalls. After coupling, the results of far field modeling showed that they did not exceed the maximum levels established by the National Environmental Council, Resolutions Nº 274/2000 and Nº 357/2005, when reaching the coast. Once the literature indicates that the local beaches near the submarine outfalls are often classified as inappropriate for bathing and with bad water quality. Thus, raw sewage dumped through the streams or directly on the beaches can be identified as responsible for the environmental contamination of the coast in the study area.
128

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Diniz, Lia Gracy Rocha 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.
129

Análise das condições ambientais e da dispersão de plumas de efluentes na região costeira centro-sul do Estado de São Paulo com uso da modelagem numérica / Analysis of environmental conditions and the dispersion of effluent plumes in the south-central coastal region of São Paulo State using numerical modeling

Yang, Samuel Hora 30 September 2016 (has links)
A região de estudo está localizada no litoral centro do Estado de São Paulo, engloba a área de proteção ambiental do Parque Estadual Marinho da Laje de Santos, e sofre a influência de três emissários submarinos e de lançamentos de esgotos pelo Rio Itanhaém. O objetivo deste trabalho foi o de analisar as condições ambientais e a dispersão das plumas de efluentes emitidas pelos emissários submarinos de Praia Grande e do Rio Itanhaém, quanto à concentração de potenciais poluentes, por meio de modelagem numérica. Objetivos secundários compreendem o interesse no conhecimento das variabilidades espaço-temporais da hidrodinâmica costeira e dos processos de dispersão das plumas de efluentes, através de simulações numéricas, incluindo a avaliação dos resultados de concentrações de indicadores de qualidade da água diante dos níveis máximos estabelecidos pelas Resoluções N.º 274/2000 e N.º 357/2005 do Conselho Nacional do Meio Ambiente. Para tanto, foram utilizados os módulos hidrodinâmico e de qualidade da água do modelo Delft3D, bem como o modelo Visual Plumes. Os resultados das simulações hidrodinâmicas foram concordantes com as feições hidrodinâmicas estabelecidas na literatura e foram validados com alto grau de confiabilidade. A modelagem de campo próximo mostrou a influência das correntes de maré e das correntes geradas pelo vento no transporte e na diluição inicial das plumas de efluentes dos emissários submarinos, onde o transporte por correntes geradas pelo vento permitiu uma diluição mais eficiente. Os resultados da modelagem de campo distante das plumas dos emissários submarinos e do Rio Itanhaém indicaram que estas plumas não afetam a qualidade da água do Parque Estadual Marinho da Laje de Santos; e que a concentração dos indicadores de qualidade da água selecionados (Escherichia coli, amônio, nitrato e fosfato) não ultrapassa os limites máximos estabelecidos pelo Conselho Nacional do Meio Ambiente ao atingir o litoral. Uma vez que a literatura aponta que as praias locais são frequentemente classificadas com balneabilidade imprópria e com má qualidade da água, os córregos que despejam esgoto bruto e não tratado diretamente nas praias podem ser apontados como os responsáveis pela contaminação ambiental do litoral da região de estudo. O modelo de qualidade da água foi validado, apesar de algumas diferenças nas comparações entre seus resultados e amostragens in situ. Foi observado que a região de estudo necessita de mais investimentos em saneamento básico e maior conscientização da população para combater a poluição ambiental local, especialmente o despejo de esgotos em córregos e praias. / The study region is located in the central coast of São Paulo, encompasses the area of environmental protection of Laje de Santos Marine State Park, and is influenced by three outfalls and sewage releases by Itanhaém River. The objective of this study was to analyze the environmental conditions and the dispersion of effluent plumes emitted by Praia Grandes submarine outfalls and Itanhaém River, concerning the concentration of potential pollutants, through numerical modeling. Secondary objectives are related to interest in the knowledge of the spatial-temporal variability of coastal hydrodynamics and processes of effluent plumes dispersion, through numerical simulations, including the evaluation of water quality indicators concentrations results as compared to the maximum levels established by the National Environmental Council Resolutions N.º 274/2000 and N.º 357/2005. For that, Delft3D models hydrodynamic and water quality modules were used, as well as the Visual Plumes model. Results of hydrodynamic simulations were consistent with the hydrodynamics features established in the literature and have been validated with a high degree of reliability. The near-field modeling showed the influence of tidal currents and wind-driven currents in the transport and initial dilution of effluent plumes from the submarine outfalls, where transport by wind-driven currents allowed a more efficient dilution. The far-field modeling results of the plumes from the submarine outfalls and Itanhaém River showed that those plumes dont affect the water quality of Laje de Santos Marine State Park; and the selected water quality indicators concentrations (Escherichia coli, ammonium, nitrate and phosphate) do not exceed the maximum levels established by the National Environmental Council when reaching the shore. Once the literature indicates that the local beaches are often classified as inappropriate for bathing and with bad water quality, streams that dump raw and untreated sewage directly on the beaches can be identified as the responsible for the environmental contamination of the study areas shore. The water quality model was validated, despite some differences in the comparisons between its results and in situ sampling. It was observed that the study area needs more investments in basic sanitation and greater awareness of the population to tackle local environmental pollution, especially the dumping of sewage into streams and beaches.
130

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Lia Gracy Rocha Diniz 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.

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