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"Utilização de duas variantes da fluorescência de raios X (EDXRF e TXRF) na determinação de chumbo em águas e sedimentos" ; Use of two variants of X-ray fluorescence (EDXRF and TXRF) in the determination of lead in waters and sediments

Moraes, Liz Mary Bueno de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/12/2004 PT
Relevância na Pesquisa
453.88875%
Este trabalho teve como objetivo principal a utilização de duas variantes da técnica analítica de fluorescência de raios X, dispersiva em energia - EDXRF e reflexão total TXRF, na determinação de Pb em amostras de águas superficiais e subterrâneas, e em sedimentos em suspensão e de fundo. Cinco amostras de cada matriz foram coletadas em uma área contaminada, nas proximidades da desativada fábrica de baterias Indústria Acumuladores Ajax Ltda., localizada no km 229 da rodovia Jaú-Ipaussu, em Bauru, SP. As variantes EDXRF com pré-concentração com APDC e medida direta por TXRF mostraram resultados satisfatórios na determinação de Pb em soluções-padrão e amostra certificada de água natural SRM1640, produzida pelo NIST, obtendo-se concentrações compatíveis com os valores esperados. A primeira técnica resultou em limite de detecção da ordem de 0,70 mg L-1, com tempo de análise de 300 s, melhor que a segunda técnica (4,46 mg L-1), em 200 s. Estas duas variantes também foram utilizadas para outros elementos químicos, como o Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn e Br, onde a EDXRF mostrou também melhores limites de detecção para todos os elementos. Para Ni, Cu e Zn, importantes na indústria de baterias, foram encontrados os limites de 0...

Identificação e quantificação de microcistinas por HPLC em reservatórios de água; Identification and Quantification of microcystins through HPLC in water reservoirs

Borges, Renata Maria Cortez
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 08/08/2008 PT
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551.15754%
A oferta de água vem se tornando cada vez mais diminuta à medida que a população, a indústria e a agricultura se expandem. A contaminação dos mananciais gerada pelo descarte de efluentes domésticos e industriais leva a eutrofização, processo pela qual grande aporte de nutrientes, particularmente fosfatos, leva ao crescimento excessivo de algas. As cianobactérias são microrganismos procariontes, que vivem nos ambientes mais adversos. A floração dessas algas quando presente em mananciais destinados ao consumo humano gera sérios problemas à saúde humana, pois algumas dessas algas podem gerar toxinas, conhecidas como hepatotoxinas, neurotoxinas e dermatotoxinas, de acordo com sua ação farmacológica. Dentre as hepatotoxinas encontramos a microcistina, um heptapeptídeo cíclico que pode levar à morte em horas ou dias. O objetivo desse estudo foi viabilizar a técnica HPLC, já proposta por outros autores, para quantificar microcistinas-LR em reservatórios de água, em escala empresarial para ser implementada em laboratórios de análise de águas. Para o desenvolvimento da técnica, foram utilizadas amostras de uma lagoa com floração de Microcystis. Para determinar a eficiência da técnica cromatográfica, foram realizados estudos com outro método...

Preconcentration of heavy metals ions from aqueous solutions by means of cellulose phosphate: An application in water analysis

De Magalhães Padilha, P.; Rocha, J. Cesar; Moreira, J. Celso; De Sousa Campos, J. Theodoro; Do Carmo Federici, C.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 317-323
ENG
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Cellulose phosphate (CELLPHOS) was studied as a collector for analytical preconcentration of traces of Cd(II), Cr(III), Cu(II) and Ni(II) from aqueous sample solution. It has been proved that using chromatographic columns packed with CELLPHOS for preconcentration and 1.0 mol 1 -1 HCl for elution the adsorbed analytes are quantitatively enriched. An enrichment factor of 20 (100 ml sample, 5 ml concentrate) was achieved by this separation procedure, which was applied to a series of water analyses (river, sea, bog water).

Simultaneous determination of As, Cu, Mn, Sb, and Se in drinking water by GFAAS with transversely heated graphite atomizer and longitudinal zeeman-effect background correction

Filho, Volnei Resta A.; Fernandes, Kelly G.; De Moraes, Mercedes; Gomes Neto, José A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 7-11
ENG
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A method has been developed for the direct and simultaneous determination of As, Cu, Mn, Sb, and Se in drinking water by electrothermal atomic absorption spectrometry (ETAAS) using a transversely heated graphite tube atomizer (THGA) with longitudinal Zeeman-effect background correction. The thermal behavior of analytes during the pyrolysis and atomization stages was investigated in 0.028 mol L-1 HNO3, 0.14 mol L-1 HNO3 and 1 + 1 (v/v) diluted water using mixtures of Pd(NO3)2 + Mg(NO3)2 as the chemical modifier. With 5 μg Pd + 3 μg Mg as the modifier, the pyrolysis and atomization temperatures of the heating program of the atomizer were fixed at 1400°C and 2100°C, respectively, and 20 μL of the water sample (sample + 0.28 mol L-1 HNO3, 1 + 1, v/v), dispensed into the graphite tube, analytical curves were established ranging from 5.00 -50.0 μg L-1 for As, Sb, Se; 10.0 - 100 μg L-1 for Cu; and 20.0 - 200 μg L-1 for Mn. The characteristic masses were around 39 pg As, 17 pg Cu, 60 pg Mn, 43 pg Sb, and 45 pg Se, and the lifetime of the tube was around 500 firings. The limits of detection (LOD) based on integrated absorbance (0.7 μg L-1 As, 0.2 μg L-1 Cu, 0.6 μg L-1 Mn, 0.3 μg L-1 Sb, 0.9 μg L-1 Se) exceeded the requirements of the Brazilian Food Regulations (decree # 310-ANVS from the Health Department)...

Avaliação da técnica 3Mtm Petrifilm tm para análises microbiológicas em água de consumo humano na região de Campinas; Evaluation of 3Mtm Petrifilm tm technique for human drink water analysis in Campinas region

Cristina de Abreu Constantino
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/03/2011 PT
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No Brasil, a Portaria MS nº. 518/2004 do Ministério da Saúde estabelece, entre outros parâmetros, a análise de coliformes totais, termotolerantes ou Escherichia coli (E. coli) e de bactérias heterotróficos para análise de água para consumo humano, em toda e qualquer situação, incluindo fontes individuais como poços, minas e nascentes. A Agência de Proteção Ambiental dos Estados Unidos (EPA) avalia métodos para diferentes aplicações ambientais, entre outras, para análise de água potável, que se aprovados, são publicados como métodos oficiais no Standard Methods for the Examination of Water and Wastewater. Este manual recomenda muitos princípios de reações e métodos para análise de água potável e é muito importantes que se compreendam as limitações e benefícios destes métodos antes de utilizá-los, para garantir a segurança e qualidade microbiológica da água de consumo humano. Os métodos convencionais de análise microbiológica de água para consumo humano requerem um mínimo de 24 horas de incubação, seguidos por procedimentos de confirmação dos resultados positivos, que duram entre 24-48 horas, o que gera uma demanda de métodos mais rápidos de análise. O uso das Placas 3M¿ Petrifilm¿ não está aprovado pela EPA...

Análise do gerenciamento de água mediante o controle de poços injetores em reservatórios heterogêneos e fraturados; Analysis of water management by injector wells control in heterogeneous and fractured reservoirs

Eduin Orlando Muñoz Mazo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/08/2013 PT
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454.10105%
A injeção de água como método para auxiliar na recuperação de hidrocarbonetos e na manutenção da pressão em reservatórios tem sido aplicada de maneira crescente nas últimas décadas devido às suas características de eficiência, baixo custo e alta disponibilidade da água, o que faz com que este procedimento seja considerado com frequência na fase de desenvolvimento de campos de petróleo, como parte da estratégia inicial de produção. No entanto, volumes cada vez maiores de água produzida são reportados pelas companhias operadoras, com grandes implicações técnicas e econômicas para as mesmas. Esta situação pode, em alguns casos, fazer com que a água deixe de ser considerada como um recurso e passe a ser vista como um empecilho à produção. Outro problema associado à injeção de água em reservatórios é a perda de injetividade causada pela diminuição da permeabilidade na região vizinha aos poços injetores, decorrente do dano de formação. Portanto, implementar soluções ao problema da perda de injetividade e considerar o controle da água injetada e produzida na etapa de lançamento e otimização de estratégias de produção têm um impacto significativo no desempenho produtivo e financeiro de um projeto de exploração e produção (E&P)...

A review on sequential injection methods for water analysis

Mesquita, Raquel B. R.; Rangel, António O.S.S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2009 ENG
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651.28117%
The development of fast, automatic and less expensive methods of analysis has always been the main aim of flowmethodologies. The search for newprocedures that still maintain the reliability and accuracy of the reference procedures is an ever growing challenge. Newrequirements are continually added to analytical methodologies, such as lower consumption of samples and reagents, miniaturisation and portability of the equipment, computer interfaces for full decision systems and so on. Therefore, the development of flow methodologies meeting the extra requirements of water analysis is a challenging work. Sequential injection analysis (SIA) presents a set of characteristics that make it highly suitable for water analysis. With sequential injection analysis, most routine determinations in waters can be performed more quickly with much lower reagent consumption when compared to reference procedures. Additionally, SIA can be a valuable tool for analyte speciation and multiparametric analysis. This paper critically reviews the overall work in this area.

Optimization and validation of FTIR method with tetrachloroethylene for determination of oils and grease in water matrices

Almeida,Cristina M. M.; Silvério,Sofia; Silva,Cláudia; Paulino,Ana; Nascimento,Sandra; Revez,Célia A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
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551.80543%
The development of methods for oils and grease (OG) determination presents several difficulties and challenges for analytical laboratories, mainly for drinking water analysis regarding its low parametric value. FTIR method with tetrachloroethylene was developed for OG monitoring and control in several water matrices, such as natural waters (surface water, groundwater and bathing water), wastewaters and drinking water. The method was validated through the application of statistical tests and calculus of the uncertainty of the analytical assay, and proved to be a good alternative to Freon 113. Results regarding the calibration, linearity, OG recovery, precision, limits of detection and quantification, and uncertainty estimation are presented and discussed. The validated method was applied for the analysis of water samples from all studied matrices and was found to be appropriate for monitoring oil and grease in these matrices at levels higher than 0.01 mg L-1.

Consequência do uso do solo nas áreas de vegetação ciliar sobre a qualidade da água do Ribeirão Samambaia, Catalão (GO); Consequences of soil usage in the areas of riparian vegetation on the water quality in the river Samambaia, Catalão (GO)

Porto, Klayre Garcia
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Geografia (RC); Regional de Catalão (RC) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Geografia (RC); Regional de Catalão (RC)
Tipo: Dissertação Formato: application/pdf
POR
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This research approaches the soil usage and occupation process and the changes occurred due to different usages of water quality and ciliary environments present in the Ribeirão Samambaia watershed area in Catalão (GO).The analysis of the indicators or variables aims to evaluate and show the main usages that have caused the reduction of water quality and the need of political applications that envisions its conservation. The recovery of ciliary environment is also part of this investigation, since its maintenance contributes to the increase of environmental quality. The study methodology used was the indicators of soil usage, such as urbanization, agriculture, pasturage and vegetal coverage, holding as reference the Mata de Galeria and the consequential analysis of water quality, based on the Environmental National Counsel Resolution (Resolução do Conselho Nacional do Meio Ambiente – CONAMA) nº. 357/2005. All of those indicators were compared to the water analysis, evaluating the influence of each usage in its quality and landscaping dynamics. The results found in the three series of analysis comprising the year 2011 have made possible the comprehension of the soil usage planning importance in order to preserve the ciliary environment and the water quality...

The Role of Water Policy in Mexico : Sustainability, Equity, and Economic Growth Considerations

Asad, Musa; Dinar, Ariel
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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With water in Mexico becoming very scarce spatially and over time, it is now a factor that limits economic activity and social well-being in several regions. The identification of priorities and trade-offs in relation to water allocation requires careful and timely attention to address an ever-growing range of complications arising from the impact of various interlinked considerations, such as sustainability of water resources, fairness, pollution, environment, basic services, development, competition, and globalization. National policies, both within the water sector and for the overall economy, need to accommodate these issues. The study reported in this note is part of a broader analysis of the sector. Its intent is to promote a stakeholders consultation process, development of a specific set of background papers to address the most pressing issues in water policy in the country. Finally, the study included the development of analytical models to assess the linkages and impacts of various policy instruments on the water sector and the economy with a focus on one river basin case study - Rio Bravo.

Water Supply and Sanitation in Tanzania : Turning Finance into Services for 2015 and Beyond

African Ministers' Council on Water
Fonte: World Bank, Nairobi Publicador: World Bank, Nairobi
Tipo: Economic & Sector Work :: Other Infrastructure Study; Economic & Sector Work
ENGLISH; EN_US
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The first round of Country Status Overviews (CSO1) published in 2006 benchmarked the preparedness of sectors of 16 countries in Africa to meet the Millenial Development Goals (MDGs) based on their medium-term spending plans and a set of success factors selected from regional experience. Combined with a process of national stakeholder consultation, this prompted countries to ask whether they had those success factors in place and, if not, whether they should put them in place. The African Ministers' Council on Water (AMCOW) commissioned the production of a second round of Country Status Overviews (CSO2s) to better understand what underpins progress in water supply and sanitation and what its member governments can do to accelerate that progress across countries in Sub-Saharan Africa (SSA). The analysis aims to help countries assess their own service delivery pathways for turning finance into water supply and sanitation services in each of four subsectors: rural and urban water supply, and rural and urban sanitation and hygiene. The CSO2 analysis has three main components: a review of past coverage; a costing model to assess the adequacy of future investments; and a scorecard which allows diagnosis of particular bottlenecks along the service delivery pathway. The CSO2 s contribution is to answer not only whether past trends and future finance are sufficient to meet sector targets...

Monitoring of estrogens, pesticides and bisphenol A in natural waters and drinking water treatment plants by solid-phase extraction–liquid chromatography–mass spectrometry

Rodríguez-Mozaz, Sara; López de Alda, Miren; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
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8 pages, 6 tables.-- PMID: 15378882 [PubMed].-- Printed version published Aug 6, 2004.-- Presented at the 3rd Meeting of the Spanish Association of Chromatography and Related Techniques and the European Workshop: 3rd Waste Water Cluster, Aguadulce (Almeria), Spain, Nov 19–21, 2003.; A multi-residue analytical method has been developed for the determination of various classes of selected endocrine disruptors. This method allows the simultaneous extraction and quantification of different estrogens (estradiol, estrone, estriol, estradiol-17-glucuronide, estradiol diacetate, estrone-3-sulfate, ethynyl estradiol and diethylstilbestrol), pesticides (atrazine, simazine, desethylatrazine, isoproturon and diuron), and bisphenol A in natural waters. In the method developed, 500 ml of water are preconcentrated on LiChrolut RP-18 cartridges. Further analysis is carried out by liquid chromatography–mass spectrometry (LC–MS) using atmospheric pressure chemical ionisation (APCI) in the positive ion mode for determination of pesticides and electrospray in the negative ionisation mode for determination of estrogens and bisphenol A. Recoveries for most compounds were between 90 and 119%, except for bisphenol A (81%) and diethylstilbestrol (70%)...

Commute Sheds as a Regional Water Management Decision Tool

Landis, Benjamin Young
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 2716611 bytes; 11133952 bytes; application/pdf; application/octet-stream
EN_US
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455.69316%
In international water management, “virtual water” analysis has been a useful tool for discussing the flow of water resource benefits amongst nations. Conceptually, an analogy can be made with “commute shed” research – the geospatial analysis of workers and where they travel to for work, created for regional developers and labor economists. Based on the rationale that clean water supply and infrastructure “produce” healthy, able workers that can generate economic output, I argue that flows of labor are thus also flows of water supply benefits. Subsequently, workers who work outside of their water utility service area are exporting these embedded economic benefits. Commute sheds can thus represent the transfer of water supply benefits within a region. Using OnTheMap 3, a recently developed software from the United States Census Bureau, I compile commute sheds for municipalities within and neighboring the Upper Neuse River Basin, North Carolina. I interpolate the water supply benefits embedded in these commute sheds, using estimated annual earnings as a proxy for economic output. Results show that within the Upper Neuse, there is a net flow of benefits from other cities into Durham. Also, there is a net flow of benefits into the Upper Neuse from cities supported by neighboring water systems...

Implementing a protocol for selection and prioritisation of organic contaminants in the drinking water value chain: case study of Rand Water, South Africa

Ncube,EJ; Voyi,K; du Preez,H
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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Approaches that prioritise chemicals according to their importance as environmental contaminants have been developed by government agencies and private industries. However, it has been noticed that few approaches, such as one published by the United States Environmental Protection Agency (USEPA), address the needs of the drinking water industry. There is also no generic approach to the selection, prioritisation and monitoring of organic contaminants in the drinking water value chain. To safeguard drinking water industry customers, it was necessary to develop a generic protocol to assist with the identification of a list of organic contaminants for monitoring in the drinking water value chain. Once the protocol was developed, it was validated in a prototype drinking water value chain. This paper describes the implementation of such a generic protocol. The exercise comprised of testing each step of the protocol, from selection of the 'pool of organic contaminants' (Step I) to recommending the final priority list of organic contaminants (Step VII). Successful implementation of the protocol took place in the Rand Water (South Africa) drinking water value chain (from catchment to tap). Expert judgment was emphasized during the implementation as each step was validated and the opinion of key stakeholders used to shape the process. The tailor-made prioritisation criteria...

The impact of physico-chemical water quality parameters on bacterial diversity in the Vaal River, South Africa

Jordaan,Karen; Bezuidenhout,Cornelius Carlos
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/30/2013 EN
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451.34926%
This study aimed to identify bacterial community structures in the Vaal River using PCR-DGGE (polymerase chain reaction denaturing gradient gel electrophoresis) and high-throughput sequencing. The impact of physico-chemical characteristics on bacterial structures was investigated through multivariate analysis. Samples were collected from 4 sampling stations along the Upper Vaal River during winter (June 2009) and summer (December 2010). Physico-chemical analysis was conducted on-site. Additional physico-chemical data were obtained from statutory bodies. DNA was directly isolated from water samples and PCR amplified using universal bacterial primer pairs. PCR products were subjected to DGGE fingerprinting and high-throughput sequencing, followed by Shannon-Weaver diversity calculations, cluster analysis and multivariate analysis. Physico-chemical parameters did not exceed the prescribed South African water quality standards for domestic use, aquatic ecosystems, livestock watering and irrigation. DGGE banding patterns revealed similar bacterial community structures for 3 of the 4 sampling stations. PCA and RDA indicated that pH, water temperature and inorganic nutrient concentrations could be used to explain changes in bacterial community structures. High-throughput sequencing data showed that bacterial assemblages were dominated by common freshwater groups: Cyanobacteria...

Analysis of grey-water used for irrigating vegetables and possible effects on soils in the vicinity of Umtata Dam, Eastern Cape

Mzini,LL; Winter,K
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 EN
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In the search for alternative and reliable water sources to irrigate vegetables for backyard gardens, an experimental field was set up in the vicinity of the Umtata Dam, north-west of the town of Umtata, to test grey-water quality and its effects on soil nutrient content following 4 successive growing seasons. Samples of grey-water that were generated from informal housing adjacent to the Umtata Dam were collected from kitchen and bath tubs/washing basins. These samples were analysed before being used for irrigating vegetable crops. The results showed that grey-water quality was 'fit for purpose' for irrigating edible vegetable plants. Although the average Na+ (16 mg/ℓ) and Cl- (15 mg/ℓ) ions were significantly higher (p = 0.05) for grey-water than other treatments, both were below the limit of 100 mg/ℓ set in the South African Water Quality Guidelines. The concentrations of nutrients and heavy metals found in the grey-water samples were significantly lower compared to the World Health Organization guidelines for the safe use of grey-water and within the target water quality range (TWQR) prescribed by South African guidelines for irrigation water. However, the study strongly recommends that grey-water be diluted in order to lower the salt content and to improve the irrigation water quality. Results from an analysis of soil samples showed no significant differences in pH as a result of applying grey-water throughout the soil profile of up to 90 cm depth. Na content of the soil irrigated with grey-water was not significantly different than that of plots where diluted grey-water and potable water were used. Therefore...

Yield-reliability analysis and operating rules for run-of-river abstractions for typical rural water supply: Siloam Village case study

Odiyo,JO; Makungo,R; Ndiritu,J; Mwaka,B; Ntuli,C
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2015 EN
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453.066%
The study focused on yield-reliability analysis and operating rules for optimum scheduling of run-of-river (ROR) abstractions for typical rural water supply schemes using Siloam Village, Limpopo Province, South Africa, as a case study. Efficient operation of water supply systems requires operating rules as decision support tools. System operation methods have hardly been developed or applied to water supply to rural communities that depend on ROR abstractions. Simulated runoff was used to derive unregulated river yield at different levels of assurance of supply (LAS) for Nzhelele River at Siloam Village using 1-day flow duration curves. Yield-reliability analysis results were used to derive operating rules. The results show that Nzhelele River can meet domestic and low-flow requirements at 50-80% (1:2-1:5) LAS. The low-flow and domestic water requirements can be partially met at 90% (1:10) LAS. The generic operating rules for ROR abstractions were consequently derived from the procedure used in developing operating rules for Nzhelele River. This enables generation of operating rules for ROR abstractions in any typical rural water supply system.

Salinity of irrigation water in the Philippi farming area of the Cape Flats, Cape Town, South Africa

Aza-Gnandji,CD Ruben; Yongxin,Xu; Raitt,Lincoln; Levy,Jonathan
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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454.93668%
This paper explores the nature, source and spatial variation of the salinity of water used for irrigation in a coastal urban farming area in Cape Town, South Africa, where water from the Cape Flats aquifer is drawn into storage ponds and used for crop irrigation. Water samples were collected in summer and winter from selected sites across the study area and were analysed for salinity as well as for concentrations of major and minor ions. Each site consists of one borehole and one pond. Isotope analysis was done for the summer samples so as to assess effects of evaporation on water quality and salinity. Descriptive statistics were used to compare the variation in range of concentration of specific ions with the recommended ranges set by the South African Department of Water Affairs and Forestry (DWAF) and the Food and Agriculture Organisation (FAO). Geographical information system (GIS) analysis was used to describe the spatial distribution of salinity across the study area, and hydro-geochemical analysis was used to assess the possibility of seawater intrusion into the aquifer system and to characterise groundwater in the study area. The results of the research showed that the concentrations of chloride, nitrate, potassium and sodium exceeded the target maximum limit according to DWAF and FAO guidelines. Groundwater and pond water were also observed to be brackish in most parts of the research area in terms of total dissolved salts content...

Assessing urban water sustainability in South Africa - not just performance measurement

Carden,K; Armitage,NP
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/30/2013 EN
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Urban water management - and the impacts that rapid population growth, industrialisation and climate change are having on it - is gaining increasing attention worldwide. In South Africa (SA), cities are under pressure to respond to not only the challenges of water availability and quality, but also to economic transformation and social division. New solutions for improving the sustainability of cities need to be found, including the development of tools to guide decision-makers. Several benchmarking initiatives have been implemented in the SA water sector - mostly in terms of performance measurement of specific water services for regulatory purposes - but none provide an integrated analysis to enable a deeper understanding of sustainability. The research described in this paper was thus focused on using a systems approach to create an understanding of, and measure the potential for, sustainability in a South African urban water context. This has been achieved through the development and evaluation of a composite index, the Sustainability Index for Integrated Urban Water Management (SIUWM). The first step involved compiling a vision of sustainability for the SA water sector, and expanding it into a sustainability framework to help identify suitable indicators for the assessment process...

A review of the modelling of water values in different use sectors in South Africa

Nieuwoudt,WL; Backeberg,GR
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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In this article several economic studies undertaken to assist with the implementation of the National Water Act (NWA) No. 36 of 1998 are reviewed. In these studies the following procedures were applied to model water use: operational research, econometric analysis, input/output analysis, willingness to pay and the conceptual framework of water markets. Main use sectors are agriculture, forestry, municipalities (domestic consumption) and the environment. Water values estimated in the studies differ significantly between sectors, as well as between and within catchment areas. Most of the studies focused on irrigated agriculture as an important use sector in terms of water volumes, food production and capital investment. Input/ output analysis indicates that South African agriculture is a less productive user of water in terms of gross income generated per unit of water. Evidence suggests that industrial and domestic use place a high value on assurance of supply of current water consumption levels. In contrast, agriculture requires large volumes of water for food production in response to market demand. The average value product of water is much higher for industry than agriculture, but the marginal value products appear similar in both sectors. From this it is concluded that water-use rights will in future be transferred from agriculture to industry but there is no urgency at present. As water is transferred in future from agriculture to domestic use and industrial use...