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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.
571

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.
572

Establishing biological and environmental drivers that influence the health assessment index as a biomonitoring tool

Phala, Balance Matseilane January 2019 (has links)
Thesis (MSc.) Zoology)) -- University of Limpopo, 2019 / In South Africa, a high anthropogenic demand of water for domestic, recreational, agricultural, urbanisation and industrial purposes has placed enormous pressure on freshwater resources and has led to a decline in water quality. In addition to measuring water quality variables, the health assessment index (HAI) advocated by AvenantOldewage and Swanepoel (1993), and modified by Crafford and Avenant-Oldewage (2009) by incorporating the inverted parasite index (IPI), and adapted further by Madanire-Moyo et al. (2012) who excluded the white blood cells counts, has been used as a rapid and inexpensive means of assessing and monitoring fish health and, in turn, the state of aquatic ecosystems. However, few studies have evaluated the latter approach in conjunction with other biomonitoring indices to assess the water quality of impoundments. Thus, the aim of this study was twofold. The first was to evaluate the HAI adapted by Madanire-Moyo et al. (2012) as a means to establish the health status of Oreochromis mossambicus (Peters, 1852) sampled from various impoundments based on a once-off survey. The second was to establish if the adapted HAI, in conjunction with selected biomonitoring indices and environmental variables, could describe monthly and seasonal fluctuations of O. mossambicus health. Once-off surveys were conducted between April and May 2016 at five impoundments. The Luphephe-Nwanedi Dam located in the upper catchment of the Limpopo River System and Rhenosterkop Dam situated in the Elands River, a tributary of the Olifants River System, served as control sites due to little or no anthropogenic activities occurring in their catchment areas. In addition, surveys were conducted at Loskop and Flag Boshielo dams and Phalaborwa Barrage situated in the main stem of the Olifants River for comparison purposes. The latter three impoundments were selected because they vary in water quality and pollution levels. Monthly surveys were carried out at Flag Boshielo Dam from February 2016 to February 2017 to establish if the biomonitoring tools and the quantification of water and sediment quality variables, could describe and predict seasonal fluctuations in the health of O. mossambicus. To this end, water quality variables were measured during each survey. Water and sediment samples were collected for analysis of nutrients and metals. Oreochromis mossambicus were collected using gill nets. Fish health was assessed using the adapted HAI that was based on observing parasite burden, haematocrit determination and anomalies in body tissues and organs in conjunction with determining gonad and iv hepato-somatic indices, the condition factor, blood glucose levels, microscopy analyses of fish gills and metal concentrations in fish muscle tissues. Water quality in terms of pH, total dissolved solids and electrical conductivity, nutrients and some aqueous and sediment metals exhibited significant differences (p ˂ 0.05) between impoundments surveyed with water quality from good to poor being in the order of: Luphephe-Nwanedi Dams ˂ Rhenosterkop Dam ˂ Loskop Dam ˂ Phalaborwa Barrage ˂ Flag Boshielo Dam. The HAI scores varied significantly (p ˂ 0.0001) between impoundments and substantiated water quality variables results during once off surveys, indicating that the health of fish from Flag Boshielo Dam were most affected when compared to the health of fish surveyed from the other impoundments. Findings from monthly surveys conducted at Flag Boshielo Dam indicated better conditions in terms of water quality variables during a period of high inflow as opposed to periods of low inflow. The HAI scores obtained for fish exhibited significant (p ˂ 0.0001) differences between the months surveyed and were found to be in agreement with the water quality findings, indicating that flow regimes and water quality of an impoundment have an impact on fish health. The condition and somatic indices findings did not seem to be sensitive enough to discriminate between the impoundments during the once off surveys. While during monthly surveys, these indices were significantly (p ˂ 0.0001) different between the months, showing to be affected by seasonal fluctuations. Knowledge of the HAI in conjunction with blood glucose levels, gill histopathology and the arithmetic mean thickness of gill epithelium (Har) best described the health of fish in both the once off and monthly surveys. In conclusion, the findings of this study emphasised the HAI premise that fish from more polluted sites would be more impacted as opposed to less impacted sites, making the HAI adapted by Madanire-Moyo et al. (2012) an effective and rapid biomonitoring tool that can be used in the field. Furthermore, this study proved that the HAI can be used either solely or in association with the parasite index (PI) or IPI depending on the objectives of the study, as no pronounced differences were evident when using HAI, HAI with PI and HAI with IPI. / National Research Foundation (NRF) and Water Research Commission (WRC)
573

Evidence for the Eutrophication of Selected Coastal Dunal Lakes: Historical Comparison of Indices for Nutrient Enrichment

Dagget, Steven Gregory 26 April 1994 (has links)
Three coastal Oregon dunal lakes, Mercer Lake, Munsel Lake, and Woahink Lake, were studied in an effort to determine if eutrophication has occurred since initial studies were conducted in 1938 and to determine each lake's current trophic status. Data collected in 1991 and 1992 for phytoplankton primary productivity; chlorophyll gi phytoplankton species, biovolumes, and densities; nutrients; optical characteristics; and dissolved oxygen were compared with historical data sets. Additional data for zooplankton, benthic invertebrates, and other relevant limnological data were used to more completely characterize each lake. Phytoplankton primary productivity measurements indicate that biological productivity has increased at each lake since 1969-1971. Chlorophyll ~ concentrations appear to have increased only at Mercer Lake. Other limnological data are insufficient to determine if and to what extent these lakes have eutrophicated. Based on data collected in 1991 and 1992, the current trophic state of each lake can be described as follows: Mercer Lake is mesotrophic to eutrophic but closer to mesotrophic, Munsel Lake is oligotrophic to mesotrophic but closer to mesotrophic, and Woahink Lake is oligotrophic to mesotrophic but closer to oligotrophic.
574

A contribution towards real-time forecasting of algal blooms in drinking water reservoirs by means of artificial neural networks and evolutionary algorithms.

Welk, Amber Lee January 2008 (has links)
Historical water quality databases from two South Australian drinking water reservoirs were used, in conjunction with various computational modelling methods for the ordination, clustering and forecasting of complex ecological data. Techniques used throughout the study were: Kohonen artificial neural networks (KANN) for data categorisation and the discovery of patterns and relationships, recurrent supervised artificial neural networks (RANN) for knowledge discovery and forecasting of algal dynamics and hybrid evolutionary algorithms (HEA) for rule-set discovery and optimisation for forecasting algal dynamics. These methods were combined to provide an integrated approach to the analysis of algal populations including interactions within the algal community and with other water quality factors, which results in improved understanding and forecasting of algal dynamics. The project initially focussed on KANN for the patternising and classification of the historical data to reveal links between the physical, chemical and biological components of the reservoirs. This offered some understanding of the system and relationships being considered for the construction of the forecasting models. Specific investigations were performed to examine past conditions and the impacts of different management regimes, as well as to discover sets of conditions that correspond with specific algal functional groups. RANN was then used to build models for forecasting both Chl-a and the main nuisance species, Anabaena, up to 7 days in advance. This method also provided sensitivity analyses to demonstrate the relationship between input and output variables by plotting the reaction of the output to variations in the inputs. Initially one year from the data set was selected for the testing of a model, as per the split-sample technique. To further test the models, it was later decided to select several years for testing to ensure the models were useful under changed conditions, and that test results were not misleading regarding the models true capabilities. RANN were firstly used to create reservoir specific or ad-hoc models. Later, the models were trained with the merged data sets of both reservoirs to create one model that could be applied to either reservoir. Another method of forecasting was trialled and compared to RANN. HEA was found to be equal or superior to RANN in predictive power, also allowed sensitivity analysis and provided an explicit, portable rule set. The HEA rule sets were initially tested on selected years of data, however to fully demonstrate the models potential, a process for k-fold cross-validation was developed to test the rule-set on all years of data. To further extend the applicability of the HEA rule-set; the idea of rule-based agents for specific lake ecosystem categories was examined. The generality of a rule-based agent means that, after successful validation on several lakes from one category, the agent could then be applied to other water bodies from within that category that had not been involved in the training process. The ultimate test of the rule-based agent for the warm monomictic and eutrophic lake ecosystem category was to be applied to a real-time monitoring and forecasting situation. The agent was fed with online, real-time data from a reservoir that belonged to the same ecosystem category but was not used in the training process. These preliminary experiments showed promising results. It can be concluded that the concept of rulebased agents will facilitate real-time forecasting of algal blooms in drinking water reservoirs provided on-line monitoring of relevant variables has been implemented. Contributions of this research include: (1) to offer insight into the capabilities of 3 kinds of computational modelling techniques applied to complex water quality data, (2) novel applications of KANN including the division of data into separate management periods for comparison of management efficiency, (3) to both qualitatively and quantitatively elucidate relationships between water quality parameters, (4) research toward the development of a forecasting tool for algal abundance 7 days in advance that could be generic for a particular lake ecosystem category and implemented in real-time, and (5) to suggest a thorough testing method for such models (k-fold cross validation). / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331584 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2008
575

Water quality and welfare assessment on United Kingdom trout farms

MacIntyre, Craig Mackenzie January 2008 (has links)
Interest in the subject of fish welfare is continuing to grow, with increasing public awareness and new legislation in the UK. Water quality has long been recognised as being of prime importance for welfare: water provides the fish with oxygen and removes and dilutes potentially toxic waste metabolites. This thesis investigates the interactions between water quality and the welfare of farmed rainbow trout (Oncorhynchus mykiss Walbaum). A literature review was undertaken to identify current recommended water quality limits for the health and welfare of farmed rainbow trout. Contradictions in the literature regarding suggested ‘safe’ water quality limits were also identified, as were deficiencies in some of the methods used to arrive at conclusions for recommended limits. The literature relating to the effects of poor water quality on welfare were also reviewed. The review ends with a discussion about water quality monitoring in the context of on-farm welfare assessment and how the information might be used in such a scheme. A telephone survey of UK rainbow trout farmers was undertaken to ascertain the level of water quality monitoring currently conducted. Participants in this study accounted for over 80% of 2005 UK rainbow trout production. It was established that 54% of farmers monitored dissolved oxygen to some extent and 69% monitored temperature, the most commonly measured water quality parameters and among the most important for health, welfare and growth. Subsequent visits were made to a sample of the participants in the telephone survey to obtain more detailed information of the farming operations, such as frequency of water quality monitoring, retention of production data and slaughter methods. Monitoring water quality will be an integral part of any on-farm welfare assessment scheme, and while measuring some water quality parameters requires specialist equipment, farmers should be able to monitor the essential parameters, dissolved oxygen and temperature. Any on-farm welfare assessment scheme for rainbow trout should incorparate fish-based measures in addition to resource-based parameters in order to provide as complete an overview of trout welfare as possible. An epidemiological study was undertaken to investigate the current status of welfare on UK rainbow trout farms and to identify risk factors for welfare. Forty-four trout farms from throughout the British Isles were visited between July 2005 and April 2007, sampling a total of 3700 fish from 189 different systems. Farms were visited twice, once in winter and once in summer, to account for any seasonal differences in fish physiology and environmental conditions. Data were collected on a range of fish parameters, together with background information on the batch from which the fish originated. Particular emphasis was placed on water quality due to the potential effects this can have on welfare. The water in each system sampled was monitored for 24 hours, with measurements of dissolved oxygen, temperature, pH, specific conductivity and ammonia taken every 15 minutes. A welfare score was developed for each fish using a multifactorial method, combining data on the condition of the fins, the condition of the gills, the stress hormone cortisol, the splenosomatic index and the mortality levels for the population of fish in the system. Using this welfare score and the individual components of the score as response variables, multi-level models were developed using the water quality, system and husbandry data collected. The primary risk factor that was associated with deteriorating welfare was disease. The purpose for which the fish was being farmed was also important, as fish farmed for the table market had on average worse welfare than those farmed for restocking fisheries. Seasonal effects, linked to higher water temperatures in summer, were associated with poorer welfare scores. Aside from seasonal effects, there is not much evidence that poor water quality is a major problem for the welfare of farmed rainbow trout in the UK. While deteriorating water quality certainly has the potential to affect the welfare of farmed rainbow trout, water quality measurements were within recommended ranges for the majority of farms visited. The results of this epidemiological study suggest that factors other than water quality may have a greater impact on trout welfare, such as exposure to diseases and production differences between farming for the table and restocking markets.
576

The assessment of groundwater quality in rural communities : two case studies from KwaZulu-Natal.

Sherman, Heidi Michelle. January 1998 (has links)
The health and life expectancy of populations in developing countries is largely determined by the availability of good quality drinking water. Boreholes and springs generally provide water of better microbiological and physical quality than surface water sources, however, they may cause health and aesthetic problems due to chemical constituents dissolved out of the host rock. As part of a pilot study to assess the health-related quality of community water supplies, samples were taken from two Quaternary catchment areas in KwaZulu-Natal. The Umkomazi catchment area is located inland from Amanzimtoti, while the Umfolozi catchment area is located north-east of Ulundi. The geology in these areas is significantly different. The Umkomazi area is predominantly underlain by basement rocks of the Natal Structural and Metamorphic Province, while the Umfolozi area is underlain by sedimentary rocks of the Karoo Supergroup. Geographical information systems (GIS) were used to examine the influence of lithology, rainfall and landuse activities on groundwater quality. Major ion analysis of groundwater samples from the Umkomazi area revealed a linear relationship between borehole and spring concentrations. Dwyka Tillite was found to produce water with the highest concentrations of major ions, while Karoo dolerite produced water with the lowest concentrations of major ions. Samples from basement rocks and Natal Group contained intermediate concentrations of major ions. In the Umfolozi area Karoo dolerite samples showed the lowest concentrations of major ions, while the Vryheid Formation and Dwyka Tillite produced the highest borehole and spring concentrations, respectively. High salinity levels in sedimentary rocks may be due to marine influence during deposition. Piper diagrams show relative enrichment of major cations and anions and Stiff diagrams showed characteristic patterns. Fluoride is associated with siliceous basement rocks and related to calcium concentrations through the solubility of calcium fluoride. The trace metals, manganese, iron and zinc were found to cause significant aesthetic problems and possibly health problems in sensitive individuals. These constituents are derived from weathering of bedrock and possibly from the corrosion of metal pipes. There is an inverse relationship between mean annual rainfall (MAR) and electrical conductivity (EC), except near the coast where windblown salinity increases with rainfall. Nitrate, ammonium and E. Coli contamination are linked to landuse activities such as occurrence of human and animal excreta near the water source and the proximity of pit latrines. It is recommended that rural communities be educated about the nature and importance of groundwater quality. / Thesis (M.Sc.)-University of Natal, Durban, 1998.
577

The use of bacteria to monitor and reflect pollution of the aquatic environment /

Chiu, Hok-cheung, Simon. January 1900 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1993.
578

Simulation of physical and chemical processes in reservoirs: Two case studies.

García Iturbe, Selma L. 12 1900 (has links)
Managing water quality aspects requires the use of integrative tools that allow a holistic approach to this problem. Water quality models coupled to hydrodynamic models are these tools. This study presents the application of the water quality model WASP coupled to the hydrodynamic model DYNHYD for two distinct reservoirs: Lake Texoma and Tocoma Reservoir. Modeling the former included simulations of water velocities, water level, and four chemical and physical compounds: chlorides, dissolved oxygen (DO), biochemical oxygen demand (BOD), and total suspended solids (TSS); and validation of the results by comparing with observed values during March - May, 1997. The latter is still under project status and the simulation was performed in a prospective way. The analysis included simulations of water velocities under current and for expected conditions, DO and BOD. Both models, DYNHYD and WASP, fitted pretty well to observed conditions for Lake Texoma and for where Tocoma Reservoir has been planned. Considering management and decision support purposes, the role of boundary and loading conditions also was tested. For Lake Texoma, controlling boundary conditions for chlorides is a determinant factor for water quality of the system. However, DO and TSS in the reservoir are governed by additional process besides the condition of the boundary. Estimated loadings for this system did not provided significant effects, even though the allocation of a load for chlorides resulted in significant changes in the trend for expected chloride concentrations at the Washita River Arm of Lake Texoma. For Tocoma Reservoir, the expected concentration of DO all over the reservoir is going to driven by boundary conditions, as well as by the management of autochthonous BOD loadings provided by vegetation decomposition. These two factors will be determinant for the resulting water quality of the future reservoir.
579

The effects of agricultural practices on tile drainage water quality

Snyder, Michael K. January 1978 (has links)
Call number: LD2668 .T4 1978 S635 / Master of Science
580

Multiobjective decision making in water resources system

Chang, Yen-Tung. January 1979 (has links)
Call number: LD2668 .T4 1979 C525 / Master of Science

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