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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.
31

Avaliação da toxicidade em água e sedimento do rio Cubatão-SP / Assessment of toxicity in water and sediment from Cubatão River - SP

Vanessa Silva Granadeiro Garcia 11 May 2012 (has links)
O monitoramento de corpos hídricos receptores de efluentes pode ajudar na manutenção e conservação desses locais, pois os poluentes podem alterar o equilíbrio, a estrutura e o funcionamento do ecossistema. Neste aspecto, o estudo em sedimentos é importante ao permitir uma avaliação mais abrangente do ecossistema aquático, onde diferentes contaminantes podem estar associados ao sedimento em concentrações superiores às das águas, podendo resultar em impactos negativos à biota aquática, a depender da biodisponibilidade. A cidade de Cubatão abriga um dos maiores pólos industriais do Brasil, onde a descarga constante de efluentes industriais e domésticos no rio Cubatão e seus afluentes acabou ocasionando um panorama de degradação dos rios. A Bacia do Rio Cubatão esta localizada entre a Grande São Paulo e a Baixada Santista, com área de 177 km2, aproximadamente. O rio Cubatão é o principal rio da região, abastecendo as cidades de Cubatão, Santos, São Vicente e parte dos municípios de Praia Grande e Guarujá. Além do abastecimento de água para a população, o rio também abastece o pólo industrial de Cubatão. O objetivo deste trabalho foi avaliar efeitos agudos e crônicos de amostras de água e de sedimento do rio Cubatão e dois de seus afluentes (Perequê e Pilões), por meio de ensaios ecotoxicológicos. Os organismos aquáticos empregados nos ensaios foram Ceriodaphnia dubia e Vibrio fischeri para avaliação de água e Hyalella azteca para avaliação de sedimento integral. A análise de crescimento corpóreo destes últimos também foi realizada. Além disso, foram realizadas Análises Químicas Instrumentais e Análise por Ativação Neutrônica em amostras de sedimentos. O estudo foi realizado entre 2010 e 2011, totalizando quatro campanhas. Foram coletadas amostras de água em nove pontos da Bacia do Rio Cubatão, e amostras de sedimento em seis pontos. Através dos ensaios realizados com V. fischeri pôde ser verificada toxicidade em todos os pontos amostrados com valores de CE(I)50 que variaram entre 31,25% e 71,61%. Os resultados obtidos com exposição de C. dubia não identificaram toxicidade, com base na análise estatística utilizada (Teste t por bioequivalência). Os ensaios de toxicidade para efeitos agudos do sedimento integral em H.azteca resultaram em toxicidade para as amostras de P2 e P5 (2ª e 4ª campanhas), com uma mortalidade superior a 50% dos organismos expostos. A análise de crescimento corpóreo identificou menor crescimento corpóreo nos organismos expostos ao sedimento coletado em P4 e P5. Com relação aos sedimentos coletados no ponto P5, os compostos endrin, dibenzeno(a,h)antraceno e antraceno ultrapassaram os valores recomendados pela Resolução Conama 344/04. Os resultados das Análises por Ativação Neutrônica evidenciaram maior contaminação por metais nos sedimentos originários de P5 e PI. / The monitoring of water quality on rivers where wastewaters are discharged may be important for the general conservation once many pollutants may alter the ecosystem balance, and life functioning. To study sediments contamination is an important tool that allows a more comprehensive assessment of the aquatic ecosystem, since many contaminants can be associated to the sediment in higher concentrations than in water and may result in negative impacts on aquatic biota. The Cubatão district is one of the largest industrial centers of Brazil. The usual discharge of industrial effluents and domestic sewage into Cubatão and its tributaries ended up causing serious waterways degradation. Cubatão River Basin is located between São Paulo and Baixada Santista (coast), covering approximately 177km2 area. Cubatão River as the main water source for the region, suppling water to Cubatão and its industrial area, and also to Santos, São Vicente and partially to Praia Grande and Guarujá municipalities. The objective of this study was to assess the toxicity for aquatic organisms concerning water and sediment sampled at Cubatão and at two tributaries (Perequê and Pilões). Chemical determinations were included in order to try identify the possible relation between biological effecs. Ceriodaphnia dubia and Vibrio fischeri were used for evaluation of water effects while Hyalella azteca were exposed to the sediments. Biometric analysis were performed on Hyalella azteca. Furthermore, chemical identification by Chromatography and Neutron Activation Analysis were carried out in sediment samples. Through V. fischeri toxicity response it could be noted signs of effects once the EC(I)50 ranged from 31.25% up to 71.61%. C. dubia results were negative to the same samples, based on statistical analysis (test \"t\" for bioequivalence).Through acute toxicity responses when H. azteca was exposed to sediments, toxicity was identified in samples from P2 and P5 (2nd and 4th campaigns): mortality exceeding 50% of exposed organisms. The biometric analysis for the H. azteca growth showed lower values for organisms exposed to sediments from P4 and P5. Chemical analysis evidenced endrin, dibenzo(a, h) anthracene and anthracene at sediments from P5, values which are not in accordance with the Conama 344/04; Neutron Activation Analysis showed high concentrations of metals for samples from the sites P5 and PI.
32

Occurrence, fate and effects of selected pharmaceuticals in sewage treatment plants.

January 2011 (has links)
Guan, Lijie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 139-161). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Table of contents --- p.vii / List of Figures --- p.X / List of Tables --- p.xiii / Abbreviations --- p.xiv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Source and Fate of Pharmaceuticals in the Environment --- p.1 / Chapter 1.2 --- Occurrence of Pharmaceuticals --- p.2 / Chapter 1.2.1 --- Wastewater --- p.2 / Chapter 1.2.2 --- Sewage sludge and soil --- p.5 / Chapter 1.2.3 --- "Surface water, ground water and seawater" --- p.6 / Chapter 1.2.4 --- Drinking water --- p.9 / Chapter 1.3 --- Effects on the Environment --- p.11 / Chapter 1.3.1 --- Antibiotic resistance --- p.11 / Chapter 1.3.2 --- Ecotoxicity on the aquatic organisms --- p.14 / Chapter 1.4 --- Removal in the Environment --- p.19 / Chapter 1.4.1 --- Adsorption --- p.20 / Chapter 1.4.2 --- Photodegradation and hydrolysis --- p.22 / Chapter 1.4.3 --- Biodegradation --- p.23 / Chapter 1.5 --- Analytical Method of Pharmaceuticals in Environmental Samples --- p.25 / Chapter 1.5.1 --- Solid-phase extraction --- p.25 / Chapter 1.5.2 --- Liquid chromatography mass spectrometry --- p.30 / Chapter 1.6 --- Objectives and Outline of Thesis --- p.33 / Chapter 2 --- OCCURRENCE AND FATE OF SELECTED PHARMCEUTICALS IN STPS --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials and Methods --- p.36 / Chapter 2.2.1 --- Choice of pharmaceuticals for study --- p.36 / Chapter 2.2.2 --- Description of sewage treatment plants (STPs) --- p.41 / Chapter 2.2.3 --- Experimental approach --- p.49 / Chapter 2.3 --- Results and Discussion --- p.55 / Chapter 2.3.1 --- Occurrence of azithromycin --- p.55 / Chapter 2.3.2 --- Fate of azithromycin --- p.59 / Chapter 2.3.3 --- Occurrence of erythromycin --- p.63 / Chapter 2.3.4 --- Fate of erythromycin --- p.67 / Chapter 2.3.5 --- Occurrence of roxithromycin --- p.70 / Chapter 2.3.6 --- Fate of roxithromycin --- p.74 / Chapter 2.3.7 --- Occurrence of atenolol --- p.75 / Chapter 2.3.8 --- Fate of atenolol --- p.79 / Chapter 2.3.9 --- Occurrence of simvastatin --- p.81 / Chapter 2.3.10 --- Fate of simvastatin --- p.84 / Chapter 2.3.11 --- Fate of pharmaceuticals during different treatment process --- p.85 / Chapter 2.3.12 --- Contribution of industrial (manufacturing) plants to STPs --- p.87 / Chapter 2.3.13 --- Seasonal variation --- p.87 / Chapter 2.4 --- Summary --- p.90 / Chapter 3 --- EFFECTS OF PHARMACEUTICALS ON ACTIVATED SLUDGE BACTERIA --- p.91 / Chapter 3.1 --- Introduction --- p.91 / Chapter 3.2 --- Materials and Methods --- p.92 / Chapter 3.2.1 --- Growth inhibition test --- p.92 / Chapter 3.2.2 --- Nitrification inhibition test --- p.94 / Chapter 3.3 --- Results and Discussion --- p.96 / Chapter 3.3.1 --- Growth inhibition of activated sludge bacteria --- p.96 / Chapter 3.3.2 --- Inhibition of nitrifying bacteria --- p.102 / Chapter 4 --- BIODEGRADATION PATHWAYS OF FOUR PHARMACEUTICALS --- p.106 / Chapter 4.1 --- Introduction --- p.106 / Chapter 4.2 --- Materials and Methods --- p.107 / Chapter 4.2.1 --- Test procedures --- p.107 / Chapter 4.2.2 --- Detection method --- p.108 / Chapter 4.3 --- Results and Discussion --- p.109 / Chapter 4.3.1 --- Degradation of atenolol --- p.109 / Chapter 4.3.2 --- Degradation of azithromycin --- p.117 / Chapter 4.3.3 --- Degradation of erythromycin --- p.129 / Chapter 4.3.4 --- Degradation of roxithromycin --- p.133 / Chapter 4.4 --- Summary --- p.134 / Chapter 5 --- GENERAL CONCLUSIONS --- p.136 / References --- p.139
33

Percepção ambiental: como os corpos d’água e a biodiversidade aquática são percebidos por jovens de ensino fundamental em Rio Verde – Goiás / Environmental perception: how water bodies and aquatic biodiversity are perceived by youngsters of elementary education in Rio Verde - Goiás

Oliveira, Rodolfo Pimentel 06 July 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-02-21T11:22:16Z No. of bitstreams: 2 Dissertação - Rodolfo Pimentel Oliveira - 2017.pdf: 2964926 bytes, checksum: 3395c6c43fe4cb29e14c8b47bf44b8fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-02-21T11:22:46Z (GMT) No. of bitstreams: 2 Dissertação - Rodolfo Pimentel Oliveira - 2017.pdf: 2964926 bytes, checksum: 3395c6c43fe4cb29e14c8b47bf44b8fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-21T11:22:46Z (GMT). No. of bitstreams: 2 Dissertação - Rodolfo Pimentel Oliveira - 2017.pdf: 2964926 bytes, checksum: 3395c6c43fe4cb29e14c8b47bf44b8fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-07-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Humanity goes through an environmental crisis, the modernization of society caused deep changes in the behavior of the whole society, there was intensification of environmental impacts in a systemic way, not restricted to the cities. The severity of the damage has not yet been dimension, but certainly, puts endangered numerous species, particularly serious situation of Cerrado, a biodiversity hotspot that is in constantly impact of agricultural activities, especially aquatic organisms, which are little studied. To preserve the quality of the environment and the survival of biodiversity, there must be involvement of society, for this, individuals have to realize, since the youth, the factors that build the environment. For this reason, was investigated in Rio Verde - Goiás, one of the largest producers of grains in the country, the perceptions of elementary school students in a countryside school and a city school about aquatic biodiversity, through questionnaires with students, observations and interviews with teachers, managers and coordinators involved. It was questioned 140 students in sixth and ninth years of elementary school II and applied 8 interviews. The results are, the perception of aquatic biodiversity and water resources is quite shallow, poor. They do not realize the wealth of aquatic biodiversity and not dialogue about their importance to the ecosystem. They have difficulty to identify environmental impacts and suggest mitigation measures. There is no difference between the perception of the students of the countryside and the city, going contrary to the social movements fighting for the identity of the camp residents. Worrying finding is that countryside students have serious theoretical difficulties, failing to answer a number of questions. We conclude that there’s no difference between the students from the countryside and the city, being need to promote environmental education consistent inside the context of students and allow the development of the awareness of students to understand the aquatic biodiversity and how it relate to many human activities. / A humanidade passa por uma crise ambiental, a modernização da sociedade provocou mudanças profundas no comportamento de toda sociedade, houve intensificação dos impactos ambientais de modo sistêmico. A gravidade dos danos ainda não possui dimensão, porém certamente coloca em risco de extinção inúmeras espécies, sendo particularmente grave a situação do Cerrado, um Hotspot de biodiversidade que sofre impactos constantes de atividades agrícolas, especialmente os organismos aquáticos, que são pouco estudados. Com o intuito de preservar a qualidade do ambiente e garantir sobrevivência da biodiversidade, deve existir envolvimento da sociedade e o envolvimento só existe a partir do momento que os indivíduos percebem o meio. Logo, objetivou-se investigar as percepções de estudantes do ensino fundamental em uma escola do campo e uma da cidade, sobre biodiversidade aquática e sobre os corpos d’agua. O trabalho foi aplicado em Rio Verde – Goiás, através de questionários com os alunos, observações e entrevistas com os professores, gestores e coordenadores envolvidos. Foram questionados 140 estudantes de sexto e nono anos do ensino fundamental II e aplicadas 8 entrevistas. Como resultados, constatou-se que a percepção sobre biodiversidade aquática e também recursos hídricos é superficial e deficiente. Não percebem a riqueza da biodiversidade aquática e não dialogam sobre sua importância para o ecossistema. Possuem dificuldade para identificar impactos ambientais e sugerir medidas de mitigação. Não existe diferenças entre a percepção dos estudantes do campo e da cidade. Ainda foi possível detectar que os estudantes do campo possuem dificuldades teóricas, deixando de responder um grande número de questões. Conclui-se que não há diferenças entre a percepção ambiental sobre biodiversidade aquática entre o campo e a cidade, sendo necessário promover ações de Educação Ambiental condizentes com o contexto dos estudantes e que permitam a sensibilização dos estudantes, para que percebam a biodiversidade aquática e como ela está ligada as inúmeras atividades humanas.
34

Factors affecting stable carbon and nitrogen isotopic signatures in food webs of the Ste. Marguerite River system (Quebec, Canada)

Trudeau, Véronique January 2005 (has links)
No description available.
35

Bioassay assessment of mine pit lake water for aquaculture and biodiversity conservation

Neil, Luke L January 2007 (has links)
For decades, researchers have been working to better understand the effects of acid and metal toxicity to aquatic organisms and to develop ways to effectively mitigate these detrimental effects. Acid mine drainage (AMD) causes environmental pollution that affects many countries having historic or current mining industries. Both surface and underground mining have the potential to create AMD and therefore adversely affect the local and adjacent environments. Through malignant mining and farming practices, damming rivers and the changing climate, surface freshwater resources are rapidly being reduced in Australia. Mine pit lakes offer a large freshwater resource that if managed correctly may sustain significant environmental, social and economic benefits from selected end uses for the future. However, assessment of mine pit lakes needs to be achieved to validate end use options. The Collie Basin located in the southwest of Western Australia is a coal mining area with many abandoned open cast mines (OCM). Some of these OCM have filled with water forming mine pit lakes that are affected by AMD. The result is large freshwater bodies with moderate to high concentrations of metals and a low pH. High concentration of metals combined with low pH is of environmental concern to both the aquatic and terrestrial ecosystem. Nevertheless, remediation techniques for AMD are available and applicable to these acidic lakes. However, the lakes in the Collie Basin are low in sulphatic compounds, therefore, restricting the use of the most common remediation treatment of bioremediation with sulphate reducing bacteria. Three remediation treatments were assessed for there efficacy in toxicity amelioration to three mine pit lakes. The treatments assessed were Limestone addition, phosphorus addition and a Rapid Catalytic Oxidation (RCO) treatment. / Toxicity assessment was achieved by means of comparing physico-chemical data to guideline trigger values and biological assessment. Biological assessment was achieved with three commonly used but ecologically and geographically relevant species. The bioassay species were the alga Chlorella protothecoides, the crustacean Ceriodaphnia cf dubia and the protozoa Tetrahymena thermophila. Aquaculture is being trialled adjacent to one of the pit lakes in limestone treated mine pit lake water. Therefore, the aquaculture fish species Bidyanus bidyanus early life stages were also used to assess residual toxicity from treated mine pit lake water. Limestone remediation of pit lake water demonstrated good reduction of dissolved metal concentrations with the exception of Zn and the ability to increase pH to circum-neutral. Biological assessment of limestone treated pit lake water showed that toxicity was removed to the three bioassay species and to the aquaculture species B. bidyanus early life stages. A larger field- scale mesocosm experiment with limestone treatment in situ is recommended. Assessment of the mesocosm experiment with biological and chemical analysis will confirm the efficacy of this treatment for full scale use.
36

A comprehensive study on the ecological toxicity and risk of triphenyltin to aquatic organisms

Yi, Xianliang, Andy, 易先亮 January 2014 (has links)
abstract / Biological Sciences / Doctoral / Doctor of Philosophy
37

Factors affecting stable carbon and nitrogen isotopic signatures in food webs of the Ste. Marguerite River system (Quebec, Canada)

Trudeau, Véronique January 2005 (has links)
Deeper understanding of the factors controlling stable isotopic signatures of aquatic organisms of all trophic levels is required if we are to properly use them in food web studies and as environmental indicators. The present field study conducted in the Ste. Marguerite River system, Quebec, compared periphyton signatures found in eight reaches (sections of a river/tributary) each composed of a series of sites with different flow regimes. Similar to patterns found in the laboratory, periphyton delta13C significantly decreased with increasing water velocity. In addition, periphyton biomass positively affected periphyton delta13C. Isotopic fractionation in favour of 12C by the periphyton communities likely leads to build-up of the heavier isotope in the boundary layer of algae. This study allows a better understanding of aquatic plant delta13C fluctuations. It also suggests how much variability in aquatic consumer delta13 C can be explained by water velocity in lotic systems.
38

Assessment of effects of chemical contaminants in dredged material on marine ecosystems and human health

Schipper, Cornelis Anton, January 1900 (has links)
Published as the author's thesis (doctor, Wageningen University, 2009). / Vita. Includes bibliographical references (p. 125-138). Includes list of author's publications (p. 147-149).
39

Assessment of effects of chemical contaminants in dredged material on marine ecosystems and human health

Schipper, Cornelis Anton, January 1900 (has links)
Published as the author's thesis (doctor, Wageningen University, 2009). / Includes bibliographical references (p. 125-138). Includes list of author's publications (p. 147-149).
40

Characterization of the effluent from an intensive marine recirculating system for the culture of fin fish, and studies on effluent based culture of microalgae /

Truesdale, Stephen G. January 2006 (has links)
Thesis (M.S.)--University of North Carolina Wilmington, 2006. / Includes bibliographical references (leaves: 77-79)

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