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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

ELABORAÇÃO E APLICAÇÃO DE UM ÍNDICE DE QUALIDADE DA ÁGUA EM CONSONÂNCIA COM A LEGISLAÇÃO BRASILEIRA

Cicilinski, Alana Deduck 02 April 2018 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-06-15T18:56:09Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Alana Deduck.pdf: 2321180 bytes, checksum: 2809c5488f4ec75ecf2a60424fafa5e0 (MD5) / Made available in DSpace on 2018-06-15T18:56:09Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Alana Deduck.pdf: 2321180 bytes, checksum: 2809c5488f4ec75ecf2a60424fafa5e0 (MD5) Previous issue date: 2018-04-02 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O índice de qualidade da água (IQA) é uma importante ferramenta para avaliar o status da qualidade da água; sintetizando as informações fornecidas por parâmetros físicos, químicos e biológicos. Este trabalho teve como objetivo geral a elaboração e aplicação de um índice de qualidade da água em conformidade com a legislação brasileira. Para o desenvolvimento de um novo índice, denominado IQAc, vinculou-se a informação dos parâmetros que o compõe e a praticidade de cálculo à legislação vigente no Brasil. Para tanto, foram selecionadas 30 estações de monitoramento da água, nos domínios da unidade hidrográfica do Alto Iguaçu- Paraná, Brasil. A estes dados, aplicaram-se três metodologias de cálculo de IQAs: o método NSF (IQANSF), Bascarán (IQAb) e o método proposto nesta pesquisa denominado Bascarán-CONAMA (IQAc). Os índices foram comparados nos diferentes períodos pluviométricos e estações do ano. Posteriormente, o IQAc foi aplicado nas Bacias Hidrográficas do Rio Tibagi e do Rio das Cinzas, localizadas no Estado do Paraná, onde foram definidos 24pontos de monitoramento da água, monitorados entre julho de 2014 e junho de 2016.Foram realizadas ponderações sob um ponto de vista pluviométrico de períodos anuais mais chuvoso e menos chuvoso, bem como numa perspectiva sazonal. Foram elaborados mapas georreferenciados, utilizando o método de interpolação do Inverso da Distância Ponderada (IDW), a fim de obter a distribuição espacial dos valores estimados. Análises estatísticas foram realizadas ao nível de significância de 1%. A partir dos resultados obtidos nesta pesquisa, pôde-se concluir que o novo índice de qualidade da água desenvolvido se demonstrou adequado para avaliação de qualidade da água. Observou-se que o desenvolvimento de IQAs em função da regionalidade é um aspecto importante para avaliação da qualidade da água nos corpos hídricos. Foi constatado que a qualidade da água na área avaliada dos rios Tibagi e Cinzas está em conformidade com os requisitos mínimos de qualidade da água que constam na legislação brasileira para rios Classe 2. Foi concluído que o fator sazonal não exerceu influência significativa na qualidade da água, uma vez que na comparação tanto entre períodos pluviométricos, quanto entre as estações do ano, não foram verificadas diferenças estatisticamente significativas nos pontos de monitoramento. / The water quality index (WQI) is an important tool for assessing the status of water quality; synthesizing the information provided by physical, chemical and biological parameters. This work had as general objective the elaboration and application of a water quality index in accordance with the Brazilian legislation. For the development of a new index, denominated IQAc, the information of the parameters that compose it and the practicality of calculation was linked to the legislation in force in Brazil. For this purpose, 30 water monitoring stations were selected, in the domains of the hydrographic unit of Alto Iguaçu- Parana, Brazil. To these data, three methodologies for calculating WQIs were applied: the NSF method (NSFWQI), Bascarán (WQIb) and the method proposed in this research denominated Bascarán-CONAMA (IQAc). The indices were compared in different pluviometric periods and seasons. Subsequently, the IQAc was applied to the Hydrographic Basins of the Tibagi River and the Cinzas River, located in the State of Parana, where 24 water monitoring points were monitored from July 2014 to June 2016.Ponderations were made from a viewpoint of more and less rainy annual periods, as well as a seasonal perspective. Georeferenced maps were elaborated using the Weighted Distance Inverse (IDW) interpolation method, in order to obtain the spatial distribution of the estimated values. Statistical analyzes were performed at a significance level of 1%. From the results obtained in this research, it was concluded that the new water quality index developed was adequate for water quality assessment. It was observed that the development of WQI as a function of regionality is an important aspect for assessing water quality in water bodies. It was found that the water quality in the evaluated area of the Tibagi and Cinzas rivers complies with the minimum water quality requirements in Brazilian legislation for Class 2 rivers. It was concluded that the seasonal factor hasn’t had a significant influence on water quality, since in the comparison between rainfall periods and seasons, no statistically significant differences were observed in the monitoring points.
32

Drinking Water Quality In Ankara: A Monitoring Study

Tezce, Gozde 01 December 2010 (has links) (PDF)
ABSTRACT DRINKING WATER QUALITY IN ANKARA: A MONITORING STUDY Tezce, G&ouml / zde MS, Department of Environmental Engineering Supervisor: Prof. Dr. &Uuml / lk&uuml / Yetis Co-Supervisor: Prof. Dr. Filiz B. Dilek December 2010, 124 pages Following the event of severe drought experienced in 2007, it was decided to use Kesikk&ouml / pr&uuml / Reservoir as an additional source of water supply for the city of Ankara. Thereupon, there have been debates on the quality of Kesikk&ouml / pr&uuml / Reservoir water with the claims that some parameters, primarily sulfate and arsenic, were not complying with the quality standards and therefore there was a threat to public health. This study aims to determine whether the water quality in the distribution network in Ankara exceeds water quality standards, and to assess the status of water quality of Ankara. To this end, monthly samples were collected from 24 districts as distribution network water and also from the Kesikk&ouml / pr&uuml / Reservoir as source water, and were monitored in terms of certain water quality parameters during the period of July 2008 through June 2009. Sulfate concentration in Kesikk&ouml / pr&uuml / Reservoir water was measured as 300-500 mg/l and this high sulfate concentration in the source water led to high sulfate values in distribution system. On the other hand, the arsenic concentration in Kesikk&ouml / pr&uuml / water was analyzed between 9-11 &micro / g/l which is lower than the expected high arsenic concentration in Kizilirmak water. Moreover, monitoring of THM and HAA in distribution network was carried out to follow DBPs formation. The highest THM concentration was observed as 109 &micro / g/l for Bilkent in July 2008. Although for some districts and some months throughout the year THM concentration was higher than the EPA Stage-I (80 &micro / g/l) and Stage-II (40 &micro / g/l) limits, mean annual THM concentrations for districts in distribution system satisfies the standards. Furthermore, the highest HAA5 concentrations were determined as 75 &micro / g/l for Dikmen in February 2009. However, annual average HAA5 in any of the districts did not exceed USEPA limit of 60 &micro / g/l. Nonetheless, total/fecal coliform bacteria, which are the indicators of microbiological contamination, were detected in distribution system between the months of July 2008 and January 2009. However, the coliform bacteria did not appear with the increasing residual chlorine in the distribution system since January 2009. Results from this study demonstrate a temporal variability in water quality / indicating water quality deterioration in the distribution system during some months, while almost full compliance with the water quality standards during other months. Overall / due to Kesikk&ouml / pr&uuml / raw water, sulfate content appears to be the major concern in the water quality when considered the one-year monitoring period.
33

Surveiller et agir : le rôle du territoire dans la mobilisation et la mise en oeuvre d’un réseau de suivi de la qualité des cours d’eau bretons (1992-2017) / Monitor and act : the role of the territory in the mobilization and implementation of a network for monitoring the quality of Breton rivers (1992-2017)

Boccarossa, Alexandra 11 October 2018 (has links)
Depuis la mise en place de la première surveillance de la qualité des cours d’eau et des rivières à l’échelle nationale en 1971, plusieurs types de mesures cohabitent à l’échelle du bassin-versant : les réseaux de surveillance pris en charge par les services de l’Etat, d’une part, les suivis qualité des eaux du bassin-versant (SQE-BV) assurés par des acteurs décentralisés d’autre part. L’acquisition de connaissances complémentaires sur l’eau issues de la mesure sur le terrain a accompagné l’évolution des pratiques locales de gestion de l’eau, de manière contrastée selon les régions, les bassins et sous-bassins. A la faveur de la contrainte réglementaire et d’un attelage partenarial Etat-Région, les cours d’eau bretons ont fait l’objet d’une politique de surveillance très développée. L’urgence d’agir face à une visibilité plus marquée de la pollution a motivé cette démarche dans les années 1990. Cette thèse illustre cette démarche régionalisée par plusieurs études de cas, dont celle du bassin précurseur de l’Yvel-Yvet. L’ensemble de la thèse, appuyée sur l’étude de ces suivis locaux et sur une temporalité de plus de vingt ans, mobilise le concept d’instrument d’action publique pour expliquer les étapes, les ressorts socio-politiques et les échelles de la mise en oeuvre de cette politique territorialisée de reconquête de la qualité des eaux. / Since the establishment of the first national waterways and rivers quality monitoring in 1971, several types of measures coexist at the drainage basin scale: on the one hand, the monitoring networks supported by the State services; on theother hand, the water quality monitoring of the drainage basin (SQE-BV) provided by decentralized actors. The acquisition of complementary knowledge on water from the field measurement has accompanied the evolution of local practices of water management, in a different way depending on the regions, the basins and sub-basins. Thanks to the regulatory constraint and a State-Region partnership, Breton waterways have been the subject of a highly developed surveillance policy. This approach was motivated in the 1990s because of the urgency to act in front of a greater pollution visibility. This thesis illustrates the regionalised approach by several case studies, including that of the precursor basin of Yvel-Yvet. The whole thesis, based on the study of these local follow-ups and on a temporality of more than twenty years, mobilizes the concept of instrument of public action to explain the stages, the socio-political motivations and the implementation scales of this territorialized policy of regaining water quality.
34

Dynamic Behavior Of Water And Air Chemistry In Indoor Pool Facilities

Lester Ting Chung Lee (11495881) 22 November 2021 (has links)
<p>Swimming is the second most common form of recreational activity in the U.S. Swimming pool water and air quality should be maintained to allow swimmers, pool employees, and spectators to use the pool facility safely. One of the major concerns regarding the health of swimmers and other pool users is the formation of disinfection by-products (DBPs) in swimming pools. Previous research has shown that volatile DBPs can adversely affect the human respiratory system. DBPs are formed by reactions between chlorine and other compounds that are present in water, most of which are introduced by swimmers, including many that contain reduced nitrogen. Some of the DBPs formed in pools are volatile, and their transfer to the gas phase in pool facilities is promoted by mixing near the air/water interface, caused by swimming and pool features.</p> <p><a>Swimming pool water treatment processes can play significant roles in governing water and air quality.</a> Thus, it is reasonable to hypothesize that water and air quality in a swimming pool facility can be improved by renewing or enhancing one or more components of water treatment.</p> <p>The first phase of the study was designed to identify and quantify changes in water and air quality that are associated with changes in water treatment at a chlorinated indoor pool facility. Reductions of aqueous NCl<sub>3 </sub>concentration were observed following the use of secondary oxidizer with its activator. This inclusion also resulted in significant decreases in the concentrations of cyanogen chloride (CNCl) and dichloroacetonitrile (CNCHCl<sub>2</sub>) in pool water. The concentration of urea, a compound that is common in swimming pools and that functions as an important precursor to NCl<sub>3</sub> formation, as well as a marker compound for introduction of contaminants by swimmers, was also reduced after the addition of activator.</p> <p>The second phase of this study involved field measurements to characterize and quantify the dynamic behavior of indoor air quality (IAQ) in indoor swimming pool facilities, particularly as related to volatile compounds that are transferred from swimming pool water to air. Measurements of water and air quality were conducted before, during, and after periods of heavy use at several indoor pool facilities. The results of a series of measurements at different swimming pool facilities allowed for examination of the effects of swimmers on liquid-phase DBPs and gas-phase NCl<sub>3</sub>. Liquid-phase NCl<sub>3</sub> concentrations were observed to gradually increase during periods of high swimmer numbers (<i>e.g.</i>, swimming meets), while liquid-phase CHCl<sub>3</sub> concentration was nearly constant in the same period. Concentrations of urea displayed a steady increase each day during these periods of intensive use. In general, the highest urea concentrations were measured near the end of each swimming meet. </p> <p>Measurements of IAQ dynamics during phase 2 of the study demonstrated the effects of swimmers on the concentrations of gas-phase NCl<sub>3 </sub>and CO<sub>2</sub>, especially during swimming meets. The measured gas-phase NCl<sub>3</sub> concentration often exceeded the suggested upper limits of 300 µg/m<sup>3</sup> or 500 µg/m<sup>3 </sup>during swimming meets, especially during and immediately after warm-up periods, when the largest numbers of swimmers were in the pool. Peak gas-phase NCl<sub>3</sub> concentrations were observed when large numbers of swimmers were present in the pools; measured gas-phase concentrations were as high as 1400 µg/m<sup>3</sup>.<sup> </sup>Concentrations of gas-phase NCl<sub>3</sub> rarely reached above 300 µg/m<sup>3</sup> during regular hours of operation. Furthermore, the types of swimmers were shown to affect the transfer of volatile compounds, such as NCl<sub>3</sub>, from water to air<sub> </sub>in pool facilities. In general, adult competition swimmers promoted more rapid transfer of these compounds than youth competition swimmers or adult recreational swimmers. The measured gas-phase CO<sub>2</sub> concentration often exceeded 1000 ppm<sub>v</sub> during swimming meets, whereas the gas-phase CO<sub>2</sub> concentration during periods of non-use of the pool tended to be close to the background (ambient) CO<sub>2</sub> concentration or slightly more than 400 ppm<sub>v</sub>. This phenomenon was largely attributed to the activity of swimmers (mixing of water and respiratory activity) and the normal respiratory activity of spectators. </p> <p>IAQ models for gas-phase NCl<sub>3</sub> and CO<sub>2</sub> were developed to relate the characteristics of the indoor pool environment to measurements of IAQ dynamics. Several assumptions were made to develop these models. Specifically, pool water and indoor air were assumed to be well-mixed. The reactions that were responsible for the formation and decay of the target compounds were neglected. Two-film theory was used to simulate the net mass-transfer rate of volatile compounds from the liquid phase to the gas phase. Advective transport into and out of the air space of the pool were accounted for. The IAQ model was able to simulate the dynamic behavior of gas-phase NCl<sub>3</sub> during regular operating hours. Predictions of gas-phase NCl<sub>3</sub> dynamics were generally less accurate during periods of intensive pool use; however, the model did yield predictions of behavior that were qualitatively correct. Strengths of the model include that it accounts for the factors that are believed to have the greatest influence on IAQ dynamics and is simple to use. Model weaknesses include that the model did not account liquid-phase reactions that are responsible for formation and decay of the target compounds. The IAQ model for NCl<sub>3</sub> dynamics could still be a useful tool to form the basis for recommendations regarding the design and operation of indoor pool facilities so as to optimize IAQ.</p><p>Measurements of CO<sub>2</sub> dynamics indicated qualitatively similar dynamic behavior as NCl<sub>3</sub>. Because of this, it was hypothesized that CO<sub>2</sub> may represent a surrogate for NCl<sub>3</sub> for monitoring and control of IAQ dynamics. To examine this issue in more detail, a conceptually similar model of CO<sub>2 </sub>dynamics was developed and applied. The model was developed to allow for an assessment of the relative contributions of liquid®gas transfer and respiration by swimmers and spectators to CO<sub>2</sub> dynamics. The results of this modeling effort indicated that the similarity of CO<sub>2</sub> transfer behavior to NCl<sub>3</sub> may allow use of CO<sub>2</sub> as a surrogate during periods with few to no spectators in the pool; however, when large numbers of spectators are present, the behavior of CO<sub>2</sub> dynamics may not be representative of NCl<sub>3</sub> dynamics because of spectator respiration.</p><p></p> <br>
35

Avaliação dos índices de qualidade da água bruta de um manancial em área urbana /

Coneglian, Milena Guirado January 2020 (has links)
Orientador: Paulo Cesar Lodi / Resumo: A Política Nacional de Recursos Hídricos (Lei nº 9.433/1997) estabelece o enquadramento dos corpos hídricos como um dos instrumentos de gestão das águas. A CETESB – Companhia Ambiental do Estado de São Paulo, que compõe o Sistema Nacional de Gerenciamento de Recursos Hídricos criado por esta Lei, mantém Programa de Monitoramento da qualidade das águas e utiliza índices de qualidade das águas como ferramenta para a interpretação de dados ambientais complexos, com a finalidade de auxiliar no processo decisório das políticas públicas municipais além de informar técnicos e público em geral. Nesse sentido, com o objetivo de avaliar a evolução da qualidade de um manancial em área urbana e a sua conformidade em relação ao enquadramento, este estudo de caso apresenta uma análise sobre os Relatórios de Qualidade das Águas Interiores do Estado de São Paulo emitidos pela CETESB com ênfase nos arquivos relativos aos resultados dos parâmetros e indicadores de qualidade das águas do ponto de interesse, o Rio Lençóis, situado na UGRHi-13, de 2009 a 2018. O índice de conformidade ao enquadramento (ICE) foi aplicado anualmente e, também, bienalmente separados o período chuvoso do seco. Os principais resultados demonstram que as variáveis que mais apresentaram-se em desacordo com a Resolução CONAMA nº 357/2005 foram ‘ferro dissolvido’, ‘Escherichia coli’, ‘fósforo’ e ‘PFTHM’, proveniente de fontes difusas de poluição e em concentrações mais elevadas após ocorrência de chuvas, relacionadas ao a... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
36

Combined effects of bioavailable organic contaminants in the aquatic environment

Emelogu, Emmanuel Steven January 2013 (has links)
Passive sampling, as opposed to the conventional spot or bottle water sampling technique, has shown to be reliable and efficient in monitoring the toxicologically relevant, freely dissolved (e.g. bioavaialable) concentrations of a wide range of organic contaminants in water. At the same time, partitioning controlled delivery (passive dosing; PD) techniques promise to overcome many of the challenges associated with toxicity testing of hydrophobic substances that may bias the interpretation of toxicity data. The present study investigated the feasibility of coupling silicone rubber passive sampling devices (SR-PSDs) with bioassay techniques for both chemical and ecotoxicological assessment of complex mixtures of organic contaminants in the aquatic environment. SR-PSDs were deployed in water at various locations within the Ythan catchment (north east, Scotland, UK), Forth estuary and the Firth of Forth (east coast of central Scotland, UK) for 7 to 9 weeks. Following retrieval, extracts from the SR-PSDs were analysed for dissolved concentrations of a variety of organic contaminants including PAHs and PCBs using GC-MS and GC-ECD respectively and were screened for a wide range of pesticides using GC-MS/MS and LC-MS/MS. The extracts were further evaluated for acute cytotoxicity (i.e. neutral red uptake assay) and EROD induction potential using rainbow trout liver cell line (Oncorhynchus mykiss; RTL-W1) and for phytotoxicity and developmental toxicity potential using algal growth inhibition test (with a marine phytoplankton, Diacronema lutheri) and fish embryo toxicity test (with embryos from zebrafish Danio rerio) respectively. Overall, the individual and total dissolved concentrations of PAHs (ΣPAH40; parent and branched) and PCBs (ΣPCB32; ortho and mono-ortho) measured in water from the Ythan, Forth estuary and Firth of Forth were relatively low compared with other studies using PSDs. A number and level of pesticides, including insecticides, herbicides and fungicides of varying hydrophobicity (log KOWs ~2.25 to ~5.31) were detected in the silicone rubber (SR) extracts from the Ythan catchment, the Forth estuary and the Firth of Forth, suggesting input mainly from agricultural run-off and possibly from direct discharges. No statistically significant (p<0.05) acute cytotoxicity was observed following 48 h exposure of RTL-W1 cells to SR extracts from the Ythan catchment. But, on a sublethal level, for every site, statistically significant EROD activity was observed to some degree following 72 h exposure. In addition, developmental and algal toxicities on embryos of D. rerio and D. lutheri respectively, were measured in all the deployed samples compared with the procedural controls (undeployed samples). Interestingly, extracts of SR-PSDs from the Forth estuary and the Firth of Forth exhibited growth inhibitions on D. lutheri that were similar to those of extracts from the Ythan, even though, fewer numbers of pesticides were detected in the Forth estuary and Firth of Forth than the Ythan. This suggests that pesticides were not solely responsible for the observed effects in the Ythan catchment. To further improve data from toxicity testing of hydrophobic substances, the study identified the use of SR O-rings as a suitable passive dosing format in in vitro toxicity tests and was partially validated through their use in dosing RTL-W1 cells with two individual PAHs and subsequently determining cytotoxicity and EROD-activity.
37

Development of monitoring program for water safety in small-scale water treatment plants in rural areas of Ecuador

Sigrell, Tone January 2018 (has links)
Globally a major health concern according to the World health organization (WHO, 2011) is gastro-intestinal infections caused by fecally contaminated water. The access to drinking water has increased due to international efforts, however the long-term sustainability and safety of the water accessed have gained criticism, and many water sources have proven to be both contaminated (UN, 2016) and badly managed (WHO, 2016a).  This thesis aims to design a monitoring program for small-scale water treatment in order to make the water supply sustainable in terms of providing safe water in a long-term perspective. A case-study was conducted for three treatment systems under constructed in rural Ecuador. The monitoring program design was based on a literature review and conducting a quantitative microbial risk assessment (QMRA). QMRA is a tool for estimating microbial risks, by using quantitative data on microbial contamination and estimating health risks. Data for the QMRA was gathered from literature and in field, and the reference pathogens used in the QMRA were E.coli O157:H7, Rotavirus and Giardia. In order to estimate infection risk from drinking water consumption for the community a QMRA-model called MRA, developed by Abrahamsson et al. (2009) was used.  Observations of the catchment areas and measurement of water quality regarding aspects other than microbial contamination indicated that the main risk was microbial contamination from fecal contaminations in the catchment area. The results from the QMRA indicated that the treatment using chlorination reduces E.coli O157:H7 under the acceptable risk level of 1/1000 infections per person and year, while the systems using biosand filters (BSF) are more effective in reducing rotavirus and Giardia. If the BSF are combined with chlorination the annual probability of infection caused by consumption of the treated water per year and person was 0.42/1000 for E.coli O157:H7, 570/1000 for Rotavirus and 25/1000 for Giardia.  The resulting monitoring program was divided into two parts: one part aimed to prevent contamination and one part designed to measure pH, temperature, conductivity, turbidity on a weekly basis and microbial indicator tests using a presence/absence method monthly. Additional testing is to be done in case of events of such character that the water quality could be effected, for example an extreme weather event.  It was concluded that the designed monitoring program could help improve the water quality in a long-term perspective, but it is dependent on the possibilities to get the necessary support, especially in the implementation phase. Recommended further studies includes collection of more site-specific data to make the QMRA results more representative, and evaluation of the monitoring program design by implementing it and optimizing it in the communities. / Runt om i världen skapar en otillräcklig tillgång på rent vatten och sanitet mycket lidande. Enlig världshälsoorganisationen WHO (2011) är ett av de ledande världshälsoproblem mag- och tarminfektioner som orsakats av vattenburna fekala patogener. Trots att antalet människor med tillgång till en dricksvattenkälla har ökat till följd av internationella ansträngningar, är hållbarheten och säkerheten för vattenkvalitén problematisk. Många dricksvattenkällor har visat sig vara både förorenade (UN, 2016) och undermåligt skötta (WHO, 2016a). Målet med denna studie är att ta fram ett vattenkvalitetsövervakningsprogram för tre småskaliga vattenreningsverk, för att dessa ska producera säkert vatten i ett långsiktigt perspektiv.  En fallstudie utfördes i byar på landsbygden i Ecuador där systemen planerats. Metoden för att ta fram ett kvalitetsövervakningsprogram var litteraturstudie och mikrobiell riskanalys. Den mikrobiella riskanalysen genomfördes med en metod som kallas Kvantitativ Mikrobiell Risk Analys (QMRA). I QMRA kan hälsorisker från mikrobiell kontamination estimeras med kvantitativdata på mikrobiell förorening. Data för att genomföra QMRA samlades från litteraturen och fältbesök. För att estimera hälsorisker i byarna i fallstudien användes en QMRA-modell som heter MRA framtaget av Abrahamsson et.al. (2009).  Observationer i fält och data på ingående vatten tydde på att de största riskerna för vattenkvalitén var fekal kontamination från djur och människor. Resultaten från QMRA:n visade att reningsverket med klorering reducerade E.coli O157:H7 till en nivå under den accepterade risknivå, satt till 1/1000 infekterade per år och person. Reningsverken med biosandfilter (BSF) var mer effektiva i reduktionen av rotavirus och Giardia. Då klor kombinerades med BSF i modellen blev den årliga infektionsnivån per person 570/1000 för Rotavirus och 25/1000 för Giardia.  Vattenkvalitetsövervakningsprogrammet delades in två delar: en kontaminationsförebyggande och en för att mäta pH, temperatur, konduktivitet och turbiditet veckovis, samt mikrobiella indikatortest med en metod som noterar förekomst av bakteriekolonier (presence/absence metod) månadsvis. Extra tester ska även göras vid sådan händelse som kan komma att påverka vattenkvalitén avsevärt, exempelvis en kraftig storm.  Slutsatsen är att det framtagna vattenkvalitetsövervakningsprogrammet kan göra att vatten-källan blir mer säker och hållbar i ett långsiktigt perspektiv, men att framgången är beroende av att rätt hjälp finns tillhanda speciellt i implementeringsfasen. Fortsatta studier behövs för att göra resultaten från QMRA:n mer representativa, exempelvis genom att samla mer områdesspecifikdata. Vidare skulle det vara intressant att implementera kvalitetsövervakningsprogrammet för att utvärdera och optimera det.
38

Análises espaço temporais da qualidade da água bruta do Aquífero Bauru na área urbana de Araguari, MG

Borges, Eduardo Humberto Campos 21 March 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / O Aquífero Bauru é considerado a unidade hidrogeológica mais importante de Araguari, Minas Gerais. A água deste aquífero é intensamente explorada devido ao baixo custo de captação, que está relacionado ao fato de ser um aquífero freático, pouco profundo e local, submetido a uma abundante recarga. No entanto, essas características o torna potencialmente vulnerável aos agentes poluidores. Este trabalho teve como objetivo oferecer um panorama geral sobre a qualidade da água bruta do aquífero Bauru, na zona urbana de Araguari, identificando possíveis fontes de poluição. As amostras de água foram coletadas em poços da concessionária de abastecimento público. Os critérios para seleção dos poços foram: distribuição espacial, operacionalidade, estrutura e zonas de risco. As amostras foram coletadas a montante do ponto de aplicação do desinfetante, garantindo os aspectos qualitativos da água bruta. Foram amostrados 68 poços, correspondendo a 80 % do poços em operação. Foram realizadas 2 campanhas de campo, sendo a primeira em novembro de 2012 e a segunda em dezembro de 2014. A amostras foram submetidas a ensaios de pH, nitrato, nitrito, fósforo, DQO, DBO5, cor aparente, turbidez, sólidos totais, sólidos dissolvidos totais, sólidos suspensos totais, sólidos voláteis totais e fixos totais. Os resultados das etapas de campo e laboratoriais permitiram o mapeamento dos parâmetros de qualidade e a identificação das áreas críticas em termos de poluição. Os resultados indicaram que vazamentos de esgoto sanitário, em áreas que apresentam elevados índices de vulnerabilidade, podem ser a causa da presença nitrato e sólidos voláteis em alguns poços analisados. Apesar disso, a água bruta do Aquífero Bauru ainda apresenta boa qualidade com propriedades físico- químicas e bacteriológicas adequadas a diversos usos. Apesar das concentrações encontradas ainda serem inferiores aos limites estabelecidos pela legislação vigente, fica evidente a importância do monitoramento contínuo da qualidade da água subterrânea extraída para o abastecimento urbano. / The Bauru Aquifer is considered the most important hydrogeological unit of the city of Araguari, Minas Gerais. The water from this aquifer is exploited due to low cost, which is related to the fact of being a shallow and local subjected to an abundant recharging. However, these characteristics makes it potentially vulnerable to pollutants. This work aimed to provide an overview of the quality of raw water from the aquifer Bauru underlying the urban area of Araguari, identifying possible sources of pollution. Water samples were collected in wells of public water utility. The criteria for selection of the wells were: spatial distribution, operation, structure and risk areas. The samples were collected upstream of disinfectant application point, ensuring the qualitative aspects of raw water. 68 wells were sampled corresponding to 80% of the wells in operation. Were held two field campaigns, the first in November 2012 and the second in December 2014. The samples were subjected to pH tests, nitrate, nitrite, phosphorus, COD, BOD, apparent color, turbidity, total solids, solids total dissolved, total suspended solids, total volatile solids and total fixed. The results of field and laboratory steps allowed the mapping of quality parameters and the identification of critical areas in terms of pollution. The results indicated that wastewater leaks in areas that have high levels of vulnerability may be the cause of nitrate and volatile solids present in some wells examined. Nevertheless, the raw water from the aquifer Bauru still has good quality with physical-chemical and bacteriological appropriate to different uses. Although the concentrations found are still below the limits established by law, it is clear the importance of continuous monitoring of groundwater quality extracted for urban supply. / Dissertação (Mestrado)
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Optimisation of water quality monitoring network design considering compliance criterion and trade-offs between monitoring information and costs

Nguyen, Thuy Hoang 03 February 2022 (has links)
Water quality monitoring (WQM) is crucial for managing and protecting riverine ecosystems. There has been a plethora of methods to select the monitoring sites, water quality parameters (WQPs), and monitoring frequencies; however, no standard method or strategy has been accepted for the river systems. Water managers have faced difficulties in adopting appropriate WQM network design methods to their local boundary conditions, monitoring objectives, monitoring costs, and legal regulations. With the elevated cost and time consumption of monitoring, approaches to evaluate and redesign the monitoring networks based on monitoring goal achievements are crucial for water managers. Hence, the overall aim of this thesis is to develop and employ a reliable yet straightforward approach to optimise and quantify the effectiveness of the WQM network in rivers. The objectives are to (i) identify the commonly used methods and the boundary conditions to apply these methods in assessing and designing of WQM networks in rivers; (ii) optimise river WQM network design based on compliance criteria; (iii) optimise river WQM network design based on the trade-offs between information provided by the monitoring network versus the monitoring expenses. A systematic review of the commonly used design methods and their resulting monitoring setups in Chapter 2 shows that multivariate statistical analysis (MVA) is a promising tool to contract the number of monitoring sites and water quality parameters. Most of the reported studies often overlook small streams and trace pollutants such as heavy metals and organic microcontaminants in the analysis. Data availability and expertise’s judgments seem to affect the selection of design methods rather than river size and the extent of the monitoring networks. The commonly found statistical methods are applied to the case study of the Freiberger Mulde (FM) river basin in eastern Germany to optimise its current monitoring network. Chapter 3 dedicates to redesign the monitoring network for compliance monitoring purposes. In Chapter 3, 82 non-biological parameters are initially screened and analysed for their violations to the environmental quality standards. The subsequent result suggests that polycyclic aromatic hydrocarbons, heavy metals, and phosphorus have been the abundant stressors that caused more than 50% of the streams in the FM river basin failing to achieve good status. The proposed approach using hierarchical cluster analysis and weighted violation factor from 22 relevant WQPs allows a reduction of 42 monitoring sites from the current 158 sites. The Mann-Kendall trend test recommends an increase in monitoring frequency of the priority substances by 12 times per annual, and a decrease in the number of sampling events for metals and general physicochemical parameters by quarterly. Overall, the results suggest that the authorities of the Saxony region should develop proper management measures targeting heavy metals and organic micropollutants to be able to achieve good WQ status by 2027 at the latest. In Chapter 4, regularly monitoring parameters with less than 15% of censored data are analysed. A combination of principal component analysis and Pearson’s correlation analysis allows the identification of 14 critical parameters that are responsible for explaining 75.1% of data variability in the FM river basin. Weathering processes, historical mining, wastewater discharges, and seasonality have been the leading causes of water quality variability. Both sampling locations and periods are observed, with the resulting mineral contents vary between locations, and the organic and oxygen content differs depending on the time period that was monitored. The monitoring costs are estimated for one monitoring event and based on laboratory, transportation, and sampling costs. The results show that under the current monitoring-intense conditions, preserving monitoring variables rather than sites seems to be more economical than the opposite practice. The current study provides and employs two statistical approaches to optimise the WQM network for the FM river basin in eastern Germany. The proposed methods can be of interests to other river basins where the historical data are available, and the monitoring costs become a constraint. The presented research also raises some concerns for future research regarding the applications of statistical methods to optimise WQM networks, which are presented in Chapter 5.
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Exploring microbial community dynamics: Positive selection for gain of RpoS function in Escherichia coli & microbial profiling of the Niagara Region

Botts, Steven January 2016 (has links)
A thesis submitted to the School of Graduate Studies in partial fulfillment of the requirements for the degree Master of Science / The effect of changing environmental conditions on microbial population structure can be observed at both the species and community level. Within the Escherichia coli species, null mutations in the RpoS stationary phase regulator are commonly selected by growth on poor carbon sources. In contrast, mutations which restore RpoS function may provide a selective advantage for cells exposed to environmental stress. The loss and subsequent restoration of RpoS form a population-level switch for adaptation within poor carbon and high stress environments. To investigate selection for RpoS reversion, we exposed rpoS-deficient E. coli to high salt concentrations and assessed the phenotype of presumptive mutants. 3-9% of salt-resistant mutants contained reversion mutations within rpoS, while in 91-97% the loss of RpoS function was maintained and mutations at alternative gene loci were identified. These results show that RpoS function can be restored in deficient E. coli under selective pressure. At the community level, the application of next-generation sequencing (NGS) technology to characterize environmental microbial diversity can potentially augment traditional water quality monitoring methods. To investigate the use of NGS in identifying microbial taxa within the Niagara Region, we collected water samples from Lake Erie, Lake Ontario, and nearby areas and examined the metagenome of microbial communities. A QIIME (Quantitative Insights Into Microbial Ecology) analysis of sequence data identified significant differences in relative microbial abundance with respect to sample metadata (e.g. location and subtype), significant correlations between relative abundance and quantitative parameters (e.g. Escherichia coli counts and fecal DNA markers), and detected pathogen-containing taxa at a relative abundance of 0.1-1.5%. These results show that sequence-based analyses can be used in conjunction with traditional identification methods to profile the metagenomic community of environmental samples and predict water quality. Both within-species and community-wide analyses thus offer insight into how microbial populations respond and adapt to environmental fluctuations. / Thesis / Master of Science (MSc) / The effect of changing environmental conditions on microbial population structure can be observed at both the species and community level. Within the Escherichia coli species, we investigated reversion of loss of function mutations in the RpoS protein regulator in high salt conditions and identified RpoS restoration under selective pressure. At the community level, we examined the microbial DNA of water samples from the Niagara Region under select environmental conditions and assessed the viability of next-generation sequencing in augmenting traditional water quality monitoring methods. Both within-species and community-wide analyses offer insight into how microbial populations respond and adapt to environmental fluctuations.

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