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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.
621

A utilização do modelo WinHSPF no estudo das cargas difusas de poluição da Bacia do Ribeirão da Estiva, SP. / The use of WinHSPF model in the study of nonpoint sources in Ribeirão da Estiva Basin's, SP.

Silva, Ana Lucia 28 August 2003 (has links)
Embora no Brasil já se reconheça a importância do aporte de cargas difusas como um dos principais responsáveis pela deterioração da qualidade das águas, faltam ferramentas, informações e maiores estudos a respeito, para que, como nos Estados Unidos, a legislação passe a regulamentar esta de fonte de poluição. O presente trabalho teve como objetivo avaliar a geração de cargas difusas na bacia de Ribeirão da Estiva usando como ferramenta o modelo WinHSPF, uma interface do modelo HSPF, mundialmente utilizado no estudo de cargas difusas, e que nesta versão traz inserido uma ferramenta de aplicação de BMP (práticas ótimas de manejo). A bacia de Ribeirão da Estiva (SP) vem recebendo uma atenção especial por parte da Companhia de Saneamento Básico do Estado de São Paulo, SABESP, a qual pretende transformá-la numa bacia piloto, com estudos acerca de fontes de poluição, alternativas de tratamento, monitoramento e obtenção de dados, entre outros. Já existe um avançado trabalho em conjunto com a sociedade civil, prefeituras e ONGs da região, visando proteger o manancial de abastecimento público e conscientizar a sociedade quanto a importância da preservação da qualidade da água de nossos mananciais. O modelo foi calibrado e validado, e demonstrou ser uma prática ferramenta para simulação de cargas difusas, principalmente para bases anuais. A aplicação de uma BMP na bacia demonstrou que ações simples e de pequeno porte, não-estruturais e estruturais, podem diminuir em até 80% a concentração dos poluentes no manancial. O modelo WinHSPF demonstrou ser uma ferramenta bastante acessível, prática e eficiente. Devido à sua flexibilidade, pode ser objeto de uso em outras bacias hidrográficas brasileiras, visando aumentar o conhecimento a respeito da geração de cargas difusas e o desenvolvimento de programas de controle de poluição. / Althoug Brazil just recognize the importance of nonpoint sources that is one of principal responsable by water quality deterioration, there aren’t tools, informations and more studies about, and like in Unite States, laws to regulation of these sources. The purpose of this project was to contribute to nonpoint source studies in Ribeirão da Estiva (SP) basin, using WinHSPF, an interface with nonpoint source model HSPF, too many used in the world to study about nonpoint sources. Ribeirão da Estiva basin have been receiving a special attention by sanitation company of São Paulo State, SABESP, that intends transform it in a pitot-basin, with studies about sources pollution, water treatment alternatives, monitoring and data obtain, etc. There is a work with civil society, city how and non governamental organization, to protect the watershed and to make sense about the needs of preservation of water quality. The model was calibrated and validated, and demonstrated to be a pratical tool to nonpoint source simulations, in special to anual simulations. The aplication of a BMP in the basin resulted in simple actions, non-strutural and structurals, that’ll reduce in 80% pollution concentration in source. WinHSPF is a access tool, pratical and eficient. The WinHSPF flexibility permits other studies in differents watersheds, to improve knowledge and development of programs about pollution control in Brazil.
622

A influência da decomposição da vegetação na qualidade da agua de reservatórios / The influence of the decomposition of vegetation on the quality of water of reservoirs

Mucci, José Luiz Negrão 06 August 1993 (has links)
O presente trabalho estuda, em escala de laboratório, a influência da decomposição de diferentes estruturas da vegetação terrestre, na qualidade física, química e biológica da água de reservatórios nos quais a vegetação foi \"afogada\". Foram testadas tanto estruturas íntegras, como amostras calcinadas. Do ponto de vista físico e químico foram avaliados: Cor, Turbidez, Condutividade, pH, Oxigênio Dissolvido, Demanda Bioquímica de Oxigênio, Nitrogênio Total e Fósforo Total. A comunidade biológica que se desenvolveu em cada caso, foi avaliada por meio do exame qualitativo do fitoplâncton (algas) e de zooplâncton (protozoários). Em ambos os casos, a maior degradação da qualidade da água foi verificada com as amostras onde havia Eucalyptus sp e Paspalum sp, que provocaram alterações consideráveis nas concentrações dos parâmetros físicos e químicos, inclusive com depleção total do Oxigênio Dissolvido. A comunidade biológica nestas amostras foi sempre característica de ambientes onde predominam os processos de oxidação de matéria orgânica. / This paper studies, in a laboratory test using samples of water from Guarapiranga reservoir (S.P), the influence of the decomposition of different parts of the submerged terrestrial vegetation, on the physico-chemical and biological quality of water of reservoirs. Parts of vegetation were submerged in a fixed volume of water, which was daily analyzed for: Color, Turbidity, Conductivity, pH, Dissolved Oxygen, Biochemical Oxygen Demand and Total Nitrogen and Phosphorous. The biological changes were evaluated through the qualitative analysis of the phytoplankton (algae) and protozooans (zooplankton) community. The effect of the decomposition of ashes was also evaluated, by sUbmerging the same amount of burned vegetation. The results show that in both cases, the strongest changes in water quality (including the total consumption of the Dissolved oxygen, in a short time) were verifyed in the experiments with samples B (Eucalyptus sp) and C (Paspalum sp).
623

The ascidian Styela plicata as a potential bioremediator of bacterial and algal contamination of marine estuarine waters

Unknown Date (has links)
The tunicate Styela plicata (Ascidiacea) was investigated for its potential use in bioremediation of bacteria and microalgae blooms from estuarine waters. Salinity tolerances, filtration rate, substrate selection, and effects on digested bacteria and ichthyofaunal communities were examined. If acclimated slowly, Styela can be placed in salinities as low as 24 parts per thousand (ppt) before increased fatalities result. An immediate decrease in salinity from 32 ppt to 20 ppt was not detrimental at short term exposure (four days). One average-sized (~40g) Styela, exposed to 105 and 106 bacteria or microalgae mL-1, can filter as much as 4.7 L hr-1 and 3.3 L hr-1, respectively. Individual tunicate filtration rates varied from hour to hour, independent of organism size, indicating that filtration rates for this species would be better reported on a population basis rather than on an individual weight or size basis. Bacterial viability in tunicate feces was assessed by ATP analysis. Bacteria were found to be non-viable after passage through the tunicate digestive tract. Filtration of eggs or larvae of recreationally or commercially important fish is of concern. The smallest eggs (~0.6mm) reported in the Indian River Lagoon belong to Cynoscion nebulosus (spotted seatrout) and Bairdiella chrysoura (silver perch). Over the course of two hours, 72.5% of 0.5 mm glass beads (simulated fish eggs) were initially retained, but many were later expelled by the tunicates. For 1.0 mm beads, 49.4% were initially retained and for 2.0 mm beads, 43.5% were initially retained. Neither the size of the oral siphon nor the size of the overall animal was correlated to bead retention. Substrate selection was investigated using the tunicate Phallusia nigra. / Newly hatched larvae preferred settling on wood (53.7%), as compared to polyethylene (30.9%), high-density polyethylene (13.0%), and polyvinyl chloride (2.4%). Overall, results of this study indicate S. plicata is very effective at removing bacteria and microalgae from estuarine waters. However, further testing is warranted regarding the unwanted removal of fish eggs and larvae before utilization of S. plicata for bioremedial purposes. / by Lisa Denham Draughon. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
624

The application of differential pulse stripping voltammetry in the determination of trace metals in wet precipitation

Le Roux, Shirley Theodora Rose January 1999 (has links)
Thesis (MTech (Physical Sciences))--Peninsula Technikon, Cape Town, 1999. / Wet deposition of toxic trace metals is the dominant mode of deposition in terrestrial ecosystems and contributes very significantly to their pollution burden. Wet deposited metals are dissolved in rainwater. They reach the vegatation in a form most favourable for uptake. Reliable analysis of toxic trace metals in rainwater is important in order to determine the impact they make on the environment. In this study, trace metals in rainwater and in dry deposition (as a control measure), have been analysed over a period of a year. These metals include cadmium, copper, cobalt, lead, nickel and zinc. The rainwater was filtered, acidified to pH2 and irradiated with UV-light. Dry deposition samples, were digested by heating in nitric acid before analysis. Differential-pulse anodic stripping voltammetry was used to determine cadmium, lead and zinc. Copper was determined by adsorptive cathodic stripping at pH7 after complexation with catechol. Cobalt and nickel were measured at pH9 by adsorptive cathodic stripping after formation of their dimethylglyoximes. Sampling was done on a daily basis from April 1996 to March 1997, on the campus of the Peninsula Technikon. The samples were collected over a 24-hour period. The total average concentration for the metals was 16.11 flg/dm3 for rainwater and 427flg/dm3 for dry deposition. Meteorological factors such as wind speed, humidity and temperature affect the distribution of pollutants and thus the trace metal levels. The levels of the metallic pollutants were thus evaluated against meteorological data. Differential-pulse stripping voltammetry is shown to be applicable for heavy metal analysis of rainwater.
625

A influência da decomposição da vegetação na qualidade da agua de reservatórios / The influence of the decomposition of vegetation on the quality of water of reservoirs

José Luiz Negrão Mucci 06 August 1993 (has links)
O presente trabalho estuda, em escala de laboratório, a influência da decomposição de diferentes estruturas da vegetação terrestre, na qualidade física, química e biológica da água de reservatórios nos quais a vegetação foi \"afogada\". Foram testadas tanto estruturas íntegras, como amostras calcinadas. Do ponto de vista físico e químico foram avaliados: Cor, Turbidez, Condutividade, pH, Oxigênio Dissolvido, Demanda Bioquímica de Oxigênio, Nitrogênio Total e Fósforo Total. A comunidade biológica que se desenvolveu em cada caso, foi avaliada por meio do exame qualitativo do fitoplâncton (algas) e de zooplâncton (protozoários). Em ambos os casos, a maior degradação da qualidade da água foi verificada com as amostras onde havia Eucalyptus sp e Paspalum sp, que provocaram alterações consideráveis nas concentrações dos parâmetros físicos e químicos, inclusive com depleção total do Oxigênio Dissolvido. A comunidade biológica nestas amostras foi sempre característica de ambientes onde predominam os processos de oxidação de matéria orgânica. / This paper studies, in a laboratory test using samples of water from Guarapiranga reservoir (S.P), the influence of the decomposition of different parts of the submerged terrestrial vegetation, on the physico-chemical and biological quality of water of reservoirs. Parts of vegetation were submerged in a fixed volume of water, which was daily analyzed for: Color, Turbidity, Conductivity, pH, Dissolved Oxygen, Biochemical Oxygen Demand and Total Nitrogen and Phosphorous. The biological changes were evaluated through the qualitative analysis of the phytoplankton (algae) and protozooans (zooplankton) community. The effect of the decomposition of ashes was also evaluated, by sUbmerging the same amount of burned vegetation. The results show that in both cases, the strongest changes in water quality (including the total consumption of the Dissolved oxygen, in a short time) were verifyed in the experiments with samples B (Eucalyptus sp) and C (Paspalum sp).
626

Modelagem do desempenho de "wetlands" construídas.

Lautenschlager, Sandro Rogério 14 May 2001 (has links)
Este trabalho contém uma revisão bibliográfica relativa à eficiência de wetlands construídas para a remoção de nitrogênio total e fósforo total. Também foram revisados diversos modelos matemáticos para a simulação desta remoção e foi efetuada uma análise crítica destes modelos. Foram empregados dados de domínio público da eficiência de remoção de nutrientes por wetlands construídas de fluxo superficial. Estes dados foram analisados procurando-se calibrar um modelo matemático para a simulação da eficiência de remoção. Observou-se, porém, que estes dados apresentam comportamento bastante complexo, sendo que, por vezes, a eficiência de remoção medida apresenta valores negativos. Partiu-se então para uma abordagem estatística destes dados, a qual poderá servir para a avaliação do risco de ocorrência de desempenho insatisfatório envolvido no dimensionamento de wetlands construídas. / This work presents a bibliographic review about the efficiency of constructed wetlands to remove total nitrogen and total phosphorus. Also many mathematics models to simulate this removal were reviewed and a critical analysis of these models was carried out. Public domain data about the removal efficiency of nutrients by constructed wetlands of surface flux were used. These data were analyzed in order to fit a mathematical model to simulate the removal efficiency. However it was found that these data present a complex behavior, including the occurrence of negative values. A statistical approach of these data was then carried out as an attempt to assess the risk of unsatisfactory performance involved in the design of constructed wetlands.
627

Proposta de um índice para avaliação de conformidade da qualidade dos corpos hídricos ao enquadramento. / Proposal of an index for assessment of conformity of quality of water bodies to the framework.

Amaro, Cristiane Araújo 24 April 2009 (has links)
O Brasil é um dos países mais ricos em água doce, mas também repleto de problemas relacionados à qualidade de suas águas, prejudicando a disponibilidade necessária para os seus múltiplos usos. O quadro de degradação da qualidade dos corpos hídricos brasileiros gerou a necessidade do estabelecimento de medidas que assegurassem a sustentabilidade destes usos e o enquadramento é considerado uma das ferramentas estratégicas para esta garantia, porque por meio desta é possível o estabelecimento de metas de qualidade da água, as quais devem ser alcançadas ou mantidas no corpo hídrico ao longo do tempo. A Política Nacional de Recursos Hídricos (Lei n. 9.433/1997) define o enquadramento como um de seus instrumentos para a gestão integrada da qualidade e quantidade da água e a Resolução CONAMA n.357/2005 classifica os corpos hídricos brasileiros segundo os seus usos preponderantes e define padrões de qualidade que devem ser obedecidos para a garantia da sustentabilidade hídrica. O acompanhamento da situação de enquadramento precisa ser encarado como uma atividade essencial para o planejamento de uma bacia hidrográfica e para auxiliar os gestores de recursos hídricos nos processos decisórios. Este trabalho apresenta o estudo de um índice capaz de informar de forma clara e objetiva a situação do corpo hídrico em relação à meta de qualidade da água proposta. O índice está baseado no IQA desenvolvido pelo Canadian Council of Ministers of the Environmental no Canadá, é um método fundamentado na excedência de padrões de qualidade da água previamente definidos, apropriado para o caso brasileiro, pois permite além da avaliação, a inclusão de novas variáveis e padrões de qualidade da água para os diversos usos hídricos. Os resultados obtidos são capazes de mostrar o comportamento dos rios estudados ao longo do tempo em relação a sua condição hídrica, permitindo a localização dos pontos da bacia que precisam de medidas para atender aos padrões estabelecidos pela Resolução CONAMA n.357. / Brazil is one of the richest countries in freshwater, but also full of problems related to the quality of the water, impairing the availability required for its multiple uses. The picture of degradation of the quality of water bodies has led Brazil to the need of establishing measures to ensure the sustainability of these uses and the framing is considered one of the strategic tools for this guarantee, with the establishment of water quality objectives, which must be achieved or kept in the water body over time. The National Water Resources Policy (Law n. 9.433/1997) establishes the framing as one of its instruments for integrated management of water quality and quantity and Resolution CONAMA n.357/2005 classifies the Brazilian water bodies according to their predominant uses and defines quality standards that must be obeyed to guarantee sustainability of the water. Monitoring the situation of environment must be seen as an essential activity to the planning of a watershed and to facilitate the decision-making process in the water resources management. This paper presents the initial study of an index able to report clearly and objectively the situation of the water body in relation to the goal of water quality proposal. The index is based on the Water Quality Index (WQI) developed by the Canadian Council of Ministers of the Environmental Canada, is a method based on exceedance of water quality standards previously defined, appropriate for the Brazilian case, it allows also the evaluation, the inclusion of new variables and water quality objectives for various water uses. The results are able to show the behavior of the rivers studied over time in relation to their water condition and identifies critical areas of the watershed in need of additional pollution control practices to achieve the desired water quality standards by CONAMA n.357 Resolution.
628

Influência da precipitação pluviométrica nas características bacteriológicas, físicas e químicas da água de diferentes mananciais de abastecimento da cidade de Jaboticabal - SP / Influence of pluviometric precipitation on the bacteriological, physical and chemical characteristics of water from different sources of water supply in the city of Jaboticabal - SP

Amaral, Luiz Augusto do 17 February 1992 (has links)
Foram analisadas, durante um período de 52 semanas, 572 amostras de água provenientes de 11 pontos de colheita localizados em três mananciais de abastecimento público da cidade de Jaboticabal, S.P, representados por um córrego, um dreno e um poço artesiano, com o objetivo de conhecer algumas características bacteriológicas, físicas e químicas e suas possíveis relações com a precipitação pluviométrica. Para cada amostra de água foram realizadas as determinações do número mais provável (NMP/100 mL) de coliformes totais, coliformes fecais e de estreptococos fecais, do número de microrganismos mesófilos (UFC/mL), pH, temperatura e turbidez, paralelamente foi observada a ocorrência de precipitação pluviométrica. Para as amostras de água do córrego, dreno e poço artesiano, nos períodos em que ocorreram precipitações pluviométricas, os valores médios das determinações do NMP de coliformes totais e coliformes fecais foram de 1307,0, 41,0 e 4,4/100 mL e de 63,0, 4,5 e 1,7/100 mL, respectivamente. Por outro lado, nos períodos em que não ocorreram precipitações pluviométricas os valores médios das referidas determinações foram de 387,0, 20,0 e 3,5/100 mL e de 92,0, 3,0 e 1,8/100 mL, respectivamente. Os NMP de estreptococos fecais e o número de microrganismos mesófilos revelaram-se, na presença de precipitações pluviométricas, com valores médios de 15,6, 4,3 e 1,5/100 mL e de 1318,0, 44,6 e 41,7 UFC/ml nas amostras de água do córrego, dreno e poço artesiano. Na ausência de precipitações pluviométricas esses valores médios foram de 15,0, 2,5 e 2,0/100 mL e de 481,0, 29,0 e 26,0 UFC/mL, respectivamente. Os valores médios do pH, temperatura e turbidez nas amostras de água do córrego, dreno e poço artesiano, quando ocorreram precipitações pluviométricas, foram de 6,8, 5,3 e 7,1; 20,9, 23,8 e 29,8oC e de 18,2, 2,7 e 2,9 ntu. Quando as precipitações pluviométricas não ocorreram os valores médios das referidas determinações foram de 6,8, 5,2 e 7,0; 18,5, 22,2 e 29,5°C e de 10,2, 1,8 e 2,5 ntu, respectivamente. As variações constatadas nos resultados obtidos nas análises bacteriológicas, físicas e químicas, nos períodos com e sem precipitações pluviométricas, revelaram-se mais acentuadas no manancial representado pelo córrego, sendo seguido pelo dreno e poço artesiano, respectivamente. A turbidez das amostras de água dos três mananciais de abastecimento estudados foi o parâmetro físico que mais apresentou correlações positivas significativas com os números de microrganismos pesquisados. As amostras de água dos três mananciais foram submetidas, ainda, à verificação da provável origem da poluição fecal, através da razão CF/EF, sendo possível determinar somente a origem da poluição fecal observada nas amostras obtidas no córrego, que foi definida como sendo humana. Os resultados obtidos revelaram que as amostras de água colhidas no córrego, dreno e no poço artesiano apresentaram características bacteriológicas, físicas e químicas diferentes frente à ocorrência de precipitações pluviométricas, sendo que as amostras do córrego foram as que evidenciaram maior influência desse fator. Novos estudos devem ser realizados sobre o comportamento de diferentes fontes de abastecimento público de águas superficiais e subterrâneas, frente às mesmas variações de condições climáticas, principalmente a ocorrência de precipitações pluviométricas, pois o conhecimento desse comportamento possibilita a tomada de medidas preventivas com a finalidade de promover e proteger a saúde da população consumidora. / An analysis was carried out in 572 water samples, over a period of 52 weeks, in order to know some bacteriological, physical and chemical caracteristics and their eventual relations with rainfall. Water samples were collected from 11 points of 3 sources of watter public supply, a stream, a drain and an artesian well, in Jaboticabal-SP. Each water sample was submitted to the most probable number (MPN/100 mL) determinations of total coliforms, fecal coliforms, fecal streptococcus, determinations of mesophylic microorganisms (CFU/mL), pH, temperature and turbidity. At the same time, the occurrence of rainfall was recorded. For all the water samples from the stream, the drain and the artesian well, collected during periods that rainfall occurred, the mean values of total and fecal coliforms MPN were 1307.0, 40.7 and 4.4/100 mL and 62.7, 4.5 and 1.7/100 mL, respectively. On the other hand, during the periods when rainfall was not observed the mean values of the above mentioned determinations were 387.0, 20.0 and 3.5/100 mL and 92.0, 3.0 and 1.8/100 mL, respectively. The MPN of fecal streptococcus and the number of mesophylic microorganisms revealed, with the occurrence of rainfall, mean values of 15.6, 4.3 and 1.5/100 mL and of 1318.0, 44.6 and 41.7 CFU/ml in the stream, drain and artesian well water samples. When rainfall did not occur, the mean values were 15.0, 2.5 and 2.0/100 ml and 481.0, 29.0 and 26.0 CFU/mL, respectively. The mean values of pH, temperature and turbidity observed in the stream, drain and artesian well water samples, when rainfall occurred were 6.8, 5.3 and 7.1, 20.9, 23.8 and 29.8°C and 18.2, 2.7 and 2.9 ntu. When rainfall did not occur, the mean values of the determinations were 6.8, 5.2 and 7.0, 18.5, 22.2 and 29.5°C and 10.2, 1.8 and 2.5 ntu, respectively. The variations observed in the results of bacterial, physical and chemical analysis, with or without rainfall, were more accentuated in the stream water, drain and artesian well, in this order. The turbidity o f water samples was the physical characteristic that showed better correlation with the number of the microorganisms analysed. The probable origin of fecal polution for water samples from the 3 sources were also researched by the FC/FS ratio, that made possible to determine only the origin of the fecal polution observed in samples from the stream, found as being of human origin. The results obtained revealed that the water samples from the stream, the drain and from the artesian well showed different bacteriological, physical and chemical characteristis when cofronted with rainfall and the stream samples were more influenced by that factor. Other studies should be dane about the behaviour of different surface and ground water supply sources, related to the same climatical condition varitions, mainly the occurrence of rainfall, since the knowledge of this behaviour makes possible to adopt preventive measures aiming at to promete and to protect the health of the consumer population.
629

Optimum planning of centralized waste treatment systems in regional water quality management

Wu, Robert Han January 2010 (has links)
Digitized by Kansas Correctional Industries
630

Enhancing Britain's rivers : an interdisciplinary analysis of selected issues arising from implementation of the Water Framework Directive

Hampson, Danyel Ian January 2016 (has links)
The Water Framework Directive requires reduced environmental impacts from human activities and for the assessment of the non-market benefits of pollution remediation schemes. This policy shift has exacerbated the research problems surrounding the physical, social and economic consequences of the relationship between land use and water quality. This research seeks to quantify the major socio-economic and environmental benefits for people which may arise as riverine pollution is reduced. To achieve these aims this research integrates primary data analyses combining choice experiment techniques with geographical information system based analyses of secondary data concerning the spatial distributions of riverine pollution. Current knowledge on the microbial quality of river water, measured by faecal indicator organism (FIO) concentrations and assessed at catchment scale, is inadequate. This research develops generic regression models to predict base- and high-flow faecal coliform (FC) and enterococci (EN) concentrations, using land cover and population (human and livestock) variables. The resulting models are then used both to predict FIO concentrations in unmonitored watercourses and to evaluate the likely impacts of different land use scenarios, enabling insights into the optimal locations and cost-effective mix of implementation strategies. Valuation experiments frequently conflate respondents’ preferences for different aspects of water quality. This analysis uses stated preference techniques to disaggregate the values of recreation and ecological attributes of water quality, thereby allowing decision makers to better understand the consequences of adopting alternative investment strategies which favour either ecological, recreational or a mix of benefits. The results reveal heterogeneous preferences across society; specifically, latent class analysis identifies three distinct groups, holding significantly different preferences for water quality. From a methodological perspective this research greatly enhances the ongoing synthesis of geographic and economic social sciences and addresses important policy questions which are of interest to a variety of stakeholders, including government departments and the water industry.

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