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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.
51

Analysis of physico-chemical characteristics of drinking water, biofilm formation and occurrence of antibiotic resistant bacteria / Suma George Mulamattathil

Mulamattathil, Suma George January 2014 (has links)
The main aim of the study was to analyse the impact of physico-chemical parameters on drinking water quality, biofilm formation and antibiotic resistant bacteria in the drinking water distribution system in Mafikeng, North West Province, South Africa. Another objective was to isolate and characterise Pseudomonas and Aeromonas species from drinking water distribution system and detect the virulence gene determinants in the isolates by PCR analysis. The physico-chemical data obtained were subjected to statistical analysis using Excel 2007 (Microsoft) and SPSS (version 14.0) programmes. Pearson’s correlation product of the moment was used to determine the correlation between EC, TDS, pH and temperature. The two tailed test of significance (p<0.05) was used in order to determine the significance of the result. Antibiotic susceptibility tests were performed using Kirby-Bauer disk diffusion method. Cluster analysis based on the antibiotic inhibition zone diameter data of different organisms isolated from different sites was determined and was expressed as dendograms using Wards algorithm and Euclidean distance of Statistica version 7. Specific PCR was used to determine the identities of presumptive Pseudomonas and Aeromonas species through amplification of the gyrB, toxA and the ecfX gene fragments. Virulence gene determinants for the confirmed Pseudomonas and Aeromonas species were detected by amplifying the exoA, exoS and exoT genes and the aerA and hylH gene fragments, respectively. A Gene Genius Bio imaging system (Syngene, Synoptics; UK) was used to capture the image using GeneSnap (version 3.07.01) software (Syngene, Synoptics; UK) to determine the relative size of amplicons. Physico-chemical parameters were monitored from three drinking water sources three times a week and bacteriological quality was monitored weekly for four months from raw and treated drinking water. Water samples were analysed for pH, temperature, total dissolved solids (TDS) and electric conductivity (EC). Bacterial consortia from drinking water samples were isolated using selective media and enumerated. The results revealed a good chemical quality of water. However, the microbial quality of the water is not acceptable for human consumption due to the presence of Pseudomonas, Aeromonas, faecal coliforms (FC), total coliforms (TC) and Heterotrophic bacteria. The results showed that the drinking water is slightly alkaline with pH value ranging between7.7 to 8.32. What is of concern was the microbial quality of the water. Pseudomonas sp., faecal coliforms (FC), total coliforms (TC) and heterotrophic bacteria were present in some of the treated water samples. The most significant finding of this study is that all drinking water samples were positive for Pseudomonas sp.(>100/100ml), but also that when one considers the TDS it demonstrates that water from the Modimola Dam has an impact on the quality of the mixed water. The prevalence and antibiotic resistance profiles of planktonic and biofilm bacteria isolated from drinking water were determined. The susceptibility of these isolates was tested against 11 antibiotics of clinical interest and the multiple antibiotic resistance (MAR) patterns were compiled. The most prevalent antibiotic resistance phenotype observed was KF-AP-C-E-OT-K-TM-A. All isolates from all samples were susceptible to ciprofloxacin. However, all faecal coliforms and Pseudomonas spp. were susceptible to neomycin and streptomycin. On the contrary all organisms tested were resistant to erythromycin (100%) trimethoprim and amoxycillin. Cluster analysis based on inhibition zone diameter data could not differentiate the various isolated into sample types. The highest prevalence of antibiotic resistant isolates was observed in Modimola Dam and Molopo eye. Biofilms were investigated in both raw water and treated drinking water sources for the presence of faecal coliforms, total coliforms, Pseudomonas spp., Aeromonas spp. and heterotrophic bacteria based on conventional microbiology and molecular methods. Drinking water biofilms were grown twice and the biofilm developing device containing copper and galvanized steel coupons were utilized. The Mini Tap filter, a home water treatment device which can be used at a single faucet, under constant flow was used during the second collection of treated water samples from cold water taps. Scanning electron micrograph revealed the existence of biofilms in all the sites investigated and the highest density was obtained on galvanized steel coupons. Isolates were tested against the antibiotics ampicillin (10μg), cephalothin (5μg), streptomycin (10μg), erythromycin (15μg), chloramphenicol (30μg), neomycin (30 μg), amoxycillin (10 μg), ciprofloxacin (5 μg), trimethoprim (25μg), kanamycin (30μg), and oxytetracycline (30μg). The multiple antibiotic resistance profiles and the presence of virulence related genes were determined. Various types of drug resistance and presence of virulence genes were observed. The most prevalent resistance phenotype observed was KF-AP-C-E-OT-TM-A. In conclusion, the results indicated the occurrence of faecal indicator bacteria in the drinking water destined for human consumption. Faecal indicator bacteria are the major contributors of poor drinking water quality and may harbour opportunistic pathogens. This highlighted survival of organisms to treatment procedures and the possible regrowth as biofilms in plumbing materials. The detection of large proportion of MAR Aeromonas and Pseudomonas species which possessed virulent genes was a cause of concern as these could pose health risks to humans. The data obtained herein may be useful in assessing the health risks associated with the consumption of contaminated water. / PhD (Microbiology), North-West University, Potchefstroom Campus, 2014
52

Evaluation of the inorganic water chemistry of the Vaal River / Angelika Möhr

Möhr, Angelika January 2015 (has links)
One of the most essential resources for life on our planet is water. A concern for water resource sustainability has shifted towards the sustainable development of clean water body resource (SWDF, 2009). Data for the Vaal River water chemistry is in abundance. However, research on the historic natural conditions influencing the inorganic water quality, is not as extensive. Inorganic data was obtained from the Department of Water Affairs, for the period 1972 to 2011, for identified monitoring stations along the Vaal River. Water quality was evaluated using various geochemical techniques to analyse the data. The results of the study indicate that the water chemistry of the Vaal River is controlled by: 1. Chemical weathering of siliceous sediment, intrusive igneous rocks and metamorphic rocks (Na+, K+, Mg2+, Ca2+ and (HCO3)-). 2. Anthropogenic influences increasing the sulphate (SO4) concentration There is no major increase in ion concentrations for the stations. However the concentrations of bicarbonate (HCO3)- and SO4 change as it progresses downstream from the first upstream station to the last downstream station. Based on the chemical characterisation, three groups have been identified. (1) Group 1 stations appear to suggest a higher influence in chemical weathering than the group 2 stations. (2) Group 2 stations appear to suggest a greater influence from SO4. (3) Group 3 stations appear to suggest an influence from both the bicarbonate and the SO4 influences. Geographically the chemical weathering is an indication of the three different groups with strong anthropogenic influences in the middle group. The water chemistry for the Vaal River is controlled by two processes, namely chemical weathering and anthropogenic influences. The prominent indication of the difference in these two influences can be seen between group 1 and group 2. A secondary conclusion indicates that a total dissolved solid (TDS) alone is not an accurate representation of anthropogenic influence (or poor water quality) on inorganic water quality of the Vaal River. The natural weathering or geological influences appears to play a more dominant role in certain sections or catchments with lower contributions from anthropogenic influences. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
53

Analysis of physico-chemical characteristics of drinking water, biofilm formation and occurrence of antibiotic resistant bacteria / Suma George Mulamattathil

Mulamattathil, Suma George January 2014 (has links)
The main aim of the study was to analyse the impact of physico-chemical parameters on drinking water quality, biofilm formation and antibiotic resistant bacteria in the drinking water distribution system in Mafikeng, North West Province, South Africa. Another objective was to isolate and characterise Pseudomonas and Aeromonas species from drinking water distribution system and detect the virulence gene determinants in the isolates by PCR analysis. The physico-chemical data obtained were subjected to statistical analysis using Excel 2007 (Microsoft) and SPSS (version 14.0) programmes. Pearson’s correlation product of the moment was used to determine the correlation between EC, TDS, pH and temperature. The two tailed test of significance (p<0.05) was used in order to determine the significance of the result. Antibiotic susceptibility tests were performed using Kirby-Bauer disk diffusion method. Cluster analysis based on the antibiotic inhibition zone diameter data of different organisms isolated from different sites was determined and was expressed as dendograms using Wards algorithm and Euclidean distance of Statistica version 7. Specific PCR was used to determine the identities of presumptive Pseudomonas and Aeromonas species through amplification of the gyrB, toxA and the ecfX gene fragments. Virulence gene determinants for the confirmed Pseudomonas and Aeromonas species were detected by amplifying the exoA, exoS and exoT genes and the aerA and hylH gene fragments, respectively. A Gene Genius Bio imaging system (Syngene, Synoptics; UK) was used to capture the image using GeneSnap (version 3.07.01) software (Syngene, Synoptics; UK) to determine the relative size of amplicons. Physico-chemical parameters were monitored from three drinking water sources three times a week and bacteriological quality was monitored weekly for four months from raw and treated drinking water. Water samples were analysed for pH, temperature, total dissolved solids (TDS) and electric conductivity (EC). Bacterial consortia from drinking water samples were isolated using selective media and enumerated. The results revealed a good chemical quality of water. However, the microbial quality of the water is not acceptable for human consumption due to the presence of Pseudomonas, Aeromonas, faecal coliforms (FC), total coliforms (TC) and Heterotrophic bacteria. The results showed that the drinking water is slightly alkaline with pH value ranging between7.7 to 8.32. What is of concern was the microbial quality of the water. Pseudomonas sp., faecal coliforms (FC), total coliforms (TC) and heterotrophic bacteria were present in some of the treated water samples. The most significant finding of this study is that all drinking water samples were positive for Pseudomonas sp.(>100/100ml), but also that when one considers the TDS it demonstrates that water from the Modimola Dam has an impact on the quality of the mixed water. The prevalence and antibiotic resistance profiles of planktonic and biofilm bacteria isolated from drinking water were determined. The susceptibility of these isolates was tested against 11 antibiotics of clinical interest and the multiple antibiotic resistance (MAR) patterns were compiled. The most prevalent antibiotic resistance phenotype observed was KF-AP-C-E-OT-K-TM-A. All isolates from all samples were susceptible to ciprofloxacin. However, all faecal coliforms and Pseudomonas spp. were susceptible to neomycin and streptomycin. On the contrary all organisms tested were resistant to erythromycin (100%) trimethoprim and amoxycillin. Cluster analysis based on inhibition zone diameter data could not differentiate the various isolated into sample types. The highest prevalence of antibiotic resistant isolates was observed in Modimola Dam and Molopo eye. Biofilms were investigated in both raw water and treated drinking water sources for the presence of faecal coliforms, total coliforms, Pseudomonas spp., Aeromonas spp. and heterotrophic bacteria based on conventional microbiology and molecular methods. Drinking water biofilms were grown twice and the biofilm developing device containing copper and galvanized steel coupons were utilized. The Mini Tap filter, a home water treatment device which can be used at a single faucet, under constant flow was used during the second collection of treated water samples from cold water taps. Scanning electron micrograph revealed the existence of biofilms in all the sites investigated and the highest density was obtained on galvanized steel coupons. Isolates were tested against the antibiotics ampicillin (10μg), cephalothin (5μg), streptomycin (10μg), erythromycin (15μg), chloramphenicol (30μg), neomycin (30 μg), amoxycillin (10 μg), ciprofloxacin (5 μg), trimethoprim (25μg), kanamycin (30μg), and oxytetracycline (30μg). The multiple antibiotic resistance profiles and the presence of virulence related genes were determined. Various types of drug resistance and presence of virulence genes were observed. The most prevalent resistance phenotype observed was KF-AP-C-E-OT-TM-A. In conclusion, the results indicated the occurrence of faecal indicator bacteria in the drinking water destined for human consumption. Faecal indicator bacteria are the major contributors of poor drinking water quality and may harbour opportunistic pathogens. This highlighted survival of organisms to treatment procedures and the possible regrowth as biofilms in plumbing materials. The detection of large proportion of MAR Aeromonas and Pseudomonas species which possessed virulent genes was a cause of concern as these could pose health risks to humans. The data obtained herein may be useful in assessing the health risks associated with the consumption of contaminated water. / PhD (Microbiology), North-West University, Potchefstroom Campus, 2014
54

Global study of lake surface water temperature (LSWT) behaviour and the tuning of a 1-dimensional model to determine the LSWTs of large lakes worldwide

Layden, Aisling January 2014 (has links)
Lake surface water temperatures (LSWTs) of 246 globally distributed large lakes were derived from Along-Track Scanning Radiometers (ATSR) for the period 1991 to 2011. These LSWTs, derived in a systematic manner, presents an ideal opportunity to study LSWT behaviour on a global scale. In this thesis, the annual cycles of lake-mean LSWTs derived from these data quantify the responses of large lakes’ surface temperatures to the annual cycle of forcing by solar radiation and the ambient air temperature. Minimum monthly net surface solar irradiance (netSSI) strongly influences minimum LSWTs of non-seasonally ice covered lakes (where lake-mean LSWT remains above 1 ºC throughout the annual cycle), explaining > 0.88 (R2 adj) of the inter-lake variation in both hemispheres. In some regions, for seasonally ice covered lakes (where lake-mean LSWT remains below 1 ºC for part of the annual cycle) the minimum monthly netSSI is a better predictor than latitude, of the length of the frozen period, which shows the importance of local cloud climatological conditions. Additionally, at lake locations between 1º S to 12º N, the netSSI, shown to peak twice annually, is reflected in the LSWT annual cycle. The summer maximum LSWTs of lakes from 25º S to 35º N show a linear decrease with increasing altitude; -3.76 + 0.17 ºC km-1 (R2 adj = 0.95), marginally lower than the corresponding air temperature -4.15 + 0.24 ºC km-1 (R2 adj = 0.95) decrease with altitude. The start and end of the period where the lake-mean LSWT is greater than 4 ºC shows strong correlation with the spring and autumn 0 ºC air temperature crossing days, (R2 adj = 0.74 and 0.80 respectively). The temporally and spatially resolved LSWT observations allows for a greater practical understanding of LSWT behaviour of large lakes. For example, lakes with a greater LSWT annual range have more observed variability in the LSWT extremes, highlighting that they may be more responsive to changes in the climate than lakes with a low annual range. The nighttime LSWT trends show stronger warming than day-night trends in the all regions, except Europe. The lake centre LSWT trends and absolute values can be generally considered representative of the lake-mean LSWT trends and absolute values. The observed LSWT time series are used to tune a 1-dimensional thermodynamic lake model, FLake. By tuning FLake using only 3 basic lake properties, shown by myself to have the most influence over LSWTs (depth, snow and ice albedo and light extinction co-efficient), the daily mean absolute differences for 244 lakes is reduced from 3.38 + 2.74 ºC (untuned model) to 0.85 + 0.61 ºC (tuned model). The effect of wind speed, lake depth, albedo and light extinction co-efficient on LSWTs is demonstrated throughout the tuning process. The modelled summer LSWT response to changes in ice-off is strongly affected by lake depth and latitude explaining 0.50 (R2 adj, p = 0.001) of the inter-lake variation in summer LSWTs. Lake depth alone explains 0.35 (p = 0.003) of the variation, highlighting the sensitivity of the summer LSWTs of deeper lakes to changes in the ice-off. Statistically significant summer/ maximum month modelled LSWT trends, from 1979-2011 are presented for lakes where the modelled LSWTs are strongly supported by observed LSWTs over the period of available observed LSWTs. For these lakes, the trends show LSWT warming of between 0.73 – 2.10 ºC for 29 lakes in northern temperate regions over the 33 year period (1979 – 2011). The modelled regional trends of all lakes over the same period show least warming in Africa of 0.30 ºC and the greatest warming in Europe, 1.35 º.
55

Legacy of historic mining and water quality in a heavily mined Scottish river catchment

Haunch, Simon January 2013 (has links)
Mine abandonment and the discharge of contaminated mine water is recognised globally as a major source of surface water and groundwater pollution. Contamination generally arises from the oxidation of sulphide minerals, principally pyrite, by the mining process, and the subsequent chemical reactions can lead to the discharge of mineralised, often acidic, iron, and sulphate rich waters. In many historically mined river catchments, mine water discharge is the main cause of poor water quality. Within the UK, managing the legacy of abandoned mines is one of the principal challenges presented by modern environmental legislation, particularly the EU Water Framework Directive, a challenge that is exacerbated by the diverse and widespread nature of historical mining. The impact and hazard associated with abandoned mining in one of the UK’s most intensively mined regions, the Almond River Catchment, Scotland, was examined via: 1) a detailed GIS mapping and investigation of historical mining processes in the catchment, 2) mine site discharge sampling, 3) detailed site investigations, 4) geochemical modelling of four mine waste sites and 5) analysis of temporal and spatial river water quality in the catchment. The results are then brought together to produce a catchment scale mine water hazard map. Mapping has identified over 300 mine sites in the catchment including coal, oil shale and ironstone mine wastes and flooded coal and oil shale mines. The historical development of oil shale retort methods has been shown to have an impact on potential hazard. Sampling of discharge waters from the different mining activities, in conjunction with detailed mineralogical analysis and geochemical modelling at the four mine waste sites has characterised the main hazards. Ironstone and pyrite bearing coal mine wastes discharge waters with highly elevated Fe and sulphate concentrations, up to 160mgl-1 and 1900mgl-1 respectively, due to extensive pyrite oxidation and acid generating salt dissolution (principally jarosite). Coal mine wastes show variable mineralogy, due to the diverse nature of coal bearing strata, and discharge waters with variable chemistry. Oil Shale mine wastes are generally depleted in pyrite due to historic processing and discharge low sulphate waters with moderately elevated Fe concentrations, up to 5mgl-1. Flooded coal mines discharge sulphate dominant alkaline waters, due to the availability of carbonate minerals in the mine complex, with elevated Fe concentrations, up to 50mgl-1, while flooded oil shale mines discharge waters with moderately elevated Fe concentrations, up to 4mgl-1, due to lower pyrite content in mine strata and reduced availability of oxygen related to mine abandonment age. Once in the surface water environment iron and sulphate display significant concentration-flow dependence: iron increases at high flows due to the re-suspension of river bed iron precipitates (Fe(OH)3); sulphate concentrations decrease with increased flow as a result of dilution. Further examination of iron and sulphate loading at low flows indicates a close correlation of iron and sulphate with mined areas; cumulative low flow load calculations indicate that coal and oil shale mining regions contribute 0.21 and 0.31 g/s of iron, respectively, to the main Almond tributary. Decreases in iron loading on river sections demonstrate the deposition and diffuse storage of iron within the river channel. This river bed iron is re-suspended with increased flow resulting in significant transport of diffuse iron downstream with load values of up to 50 g/s iron. Based on this hazard classification, a catchment scale mine water hazard map has been developed. The map allows the prioritisation of actions for future mine water management.
56

Ämnestransport med grundvatten i hydrogeologiska typmiljöer

Winnerstam, Björn January 2005 (has links)
<p>Certain types of waste, e.g. bottom ash originating from municipal solid waste incineration (MSWI bottom ash) can be used as road construction materials. A potential problem is the possibility of substances leaching out of the road and spreading in the surrounding groundwater.</p><p>The aim of this master’s thesis is to conclude whether hydrogeological type settings can be employed to, based on local conditions, provide an estimate of the probable spreading of these substances in the surrounding groundwater, and whether certain types of soils can be identified as being less suitable for the localization of a MSWI bottom ash road. A hydrogeological type setting is defined as a mappable unit with similar hydrogeological properties. An advantage of this approach would be that mainly existing maps and surveys could form the basis for the assessment.</p><p>The work has been performed by placing a hypothetical road construction in different hydrogeological type settings. The expected patterns of spreading has then been evaluated using theoretical reasoning and analytical and numerical models.</p><p>The method can be used. In the report various type settings are defined. In several cases further information will be required to render possible a more exact estimate of the spreading. By locating the road on less permeable soils to reduce the local spreading of substances in groundwater, a greater proportion of the water will be drained as surface water. Thus it becomes important to take into account surface water transport aswell. In the report a procedure to estimate the maximum concentrations in groundwater at locations situated downstream the road is presented. This estimate could be used as basis for a more balanced valuation of appropriateness, e.g. by relating the estimated concentrations to background values.</p> / <p>Vissa typer av avfall, exempelvis slaggrus (sorterad bottenaska från avfallsförbränning), kan användas som vägbyggnadsmaterial. Ett potentiellt problem är möjligheten att ämnen lakas ut ur vägen och sprids i omgivande grundvatten.</p><p>Syftet med detta examensarbete är att avgöra om hydrogeologiska typmiljöer kan användas för att, utifrån omgivningens förutsättningar, ge en bild av hur den vidare spridningen av dessa ämnen i omgivande grundvatten sannolikt ser ut, och om vissa typer av mark kan pekas ut som mindre lämpade för lokalisering av en slaggrusväg. En hydrogeologisk typmiljö definieras som ett område möjligt att avgränsa med avseende på karakteristiska hydrogeologiska förhållanden. En fördel med angreppssättet skulle vara att underlagsmaterialet till bedömningen då kan utgöras av i huvudsak befintligt kartmaterial.</p><p>Studien har utförts genom att en hypotetisk vägkonstruktion placerats in i olika hydrogeologiska typmiljöer. De troliga spridningsscenarierna har sedan utvärderats genom teoretiska resonemang, samt genom användande av analytiska och numeriska modeller.</p><p>Metodiken går att använda och i rapporten definieras olika typmiljöer. I flera fall kommer platsspecifik kunskap behöva inhämtas för en närmare beskrivning av spridningsbilden. Genom placering av vägen på tätare mark för att minska lokal spridning av ämnen i grundvatten kommer en större andel av vattnet att avledas som ytvatten. Därmed blir det viktigt att även inhämta kunskap om transport med ytvatten. I rapporten presenteras också en metod för uppskattning av maximala halter i grundvatten nedströms en väg. Denna metod kan användas som underlag för en mer nyanserad värdering av lämplighet, genom att de uppskattade halterna relateras till bakgrundsvärden eller lämpliga riktvärden.</p>
57

Studie kvality vody ve studánkách CHKO Křivoklátsko / The study of water quality in wells Protected Landscape Area Křivolkátsko

Vobecká, Kateřina January 2014 (has links)
The water quality is an essential abiotic factor of the environment, particularly for water-linked ecosystems. It also necessary for human society for which the absence of drinking water could have disastrous consequences. This diploma thesis is focused on small resources of groundwater located in the protected area Křivoklátsko - the springs and wells. A water from the monitored wells was subjected to basic physico-chemical analysis plus some of these wells were also tested for microbiological contamination. These results were presented against current legislation and were also compared with results from Tomáš Brabenec's bachelor thesis. Key words: Křivoklátsko, wells, springs, water quality
58

O impacto do uso do solo na contaminação por agrotóxicos das águas superficiais de abastecimento público / The impact of land use in the contamination of the superficial waters of public supply by pesticides

Veiga, Denise Piccirillo Barbosa da 05 May 2017 (has links)
Introdução: A qualidade e quantidade das águas superficiais estão diretamente relacionadas com as atividades econômicas presentes nas bacias hidrográficas e seus níveis de preservação. O aumento no uso de agrotóxicos pode contribuir para a contaminação do solo e da água, sobretudo em bacias hidrográficas agrícolas. A prevenção da contaminação dos mananciais é essencial para garantir a qualidade da água e diminuir os riscos à saúde humana, para tanto é preciso identificar como o uso e a ocupação do solo impactam os recursos hídricos, sua qualidade e seu equilíbrio hidrológico. Objetivo: Caracterização ambiental de duas bacias de mananciais de abastecimento público de forma a identificar áreas vulneráveis quanto à contaminação de agrotóxicos. Método: Aplicação do modelo hidrológico SWAT para caracterização da bacia e para simulação do ciclo hidrológico. Divisão da bacia hidrográfica em subbacias de acordo com o predomínio da ocupação do solo. Trabalho de campo para identificação de fontes pontuais de contaminação. Resultados: Foi verificado o impacto do uso e ocupação do solo no balanço hídrico das bacias. O escoamento superficial foi um dos principais meios de contaminação dos corpos dágua e esteve relacionado a presença de vegetação. Áreas de maior preservação apresentaram menor escoamento superficial enquanto àquelas com predomínio de agricultura e de solo exposto apresentaram valores maiores. A partir desses dados foram identificadas as áreas prioritárias para melhor gestão do uso de agrotóxicos por apresentarem potencial de contaminação dos corpos dágua. Conclusão: O modelo SWAT e as ferramentas de geoprocessamento se mostraram adequadas para a caracterização do uso do solo e os resultados fornecem subsídios para melhoria das ações de vigilância da qualidade da água nos municípios / Introduction: The surface waters quality and quantity are directly related to the economic activities present in the river basins and their levels of preservation. The increase in the use of pesticides can contribute to the contamination of soil and water, especially in agricultural watersheds. Preventing the contamination of water sources is essential to guarantee water quality and reduce risks to human health. Therefore, it is necessary to identify how the land use impacts water resources, their quality and their hydrological balance. Objective: Environmental characterization of two watersheds of public supply sources in order to identify vulnerable areas for the contamination of pesticides. Method: Application of the SWAT hydrological model for basin characterization and simulation of the hydrological cycle. Division of watershed in subbasins according to the predominance of the land use. Fieldwork to identify point sources of contamination. Results: The impact of land use and occupation on the water balance of the watersheds was verified. Surface runoff was one of the main means of contamination of water bodies and was related to the presence of vegetation in the area. Areas of greater preservation presented lower surface runoff while those with predominance of agriculture and exposed soil showed higher values. Priority areas for better use of agrochemicals were identified because they present potential for contamination of water bodies. Conclusion: The SWAT model and spatial tools were adequate for the characterization of land use and the results provide subsidies for the improvement of water quality monitoring actions in municipalities
59

Monitoramento de agrotóxicos em áreas irrigadas por pivô central na microbacia do Tijunqueiro, município de Morrinhos, Goiás / Pesticides monitoring in irrigated areas by central pivot in the Tijunqueiro Watershed municipality of Morrinhos, Goias

Rocha, Aderbal Almeida 12 August 2011 (has links)
A importância dos agrotóxicos para o sistema de produção agrícola é indiscutível, uma vez que constituem parte dos insumos básicos. No entanto, é fundamental que sejam adequadamente utilizados para a preservação da qualidade não só do produto cultivado, mas também dos próprios recursos naturais, especialmente o solo e a água. Neste estudo, foi realizado o monitoramento dos agrotóxicos utilizados em lavouras irrigadas por pivô central, na microbacia do Tijunqueiro, município de Morrinhos, estado de Goiás, que apresentaram potencial de contaminação ambiental (critérios da Agência de Proteção Ambiental dos Estados Unidos EPA, índice GUS Groundwater Ubiquity Score, método GOSS e do Instituto Brasileiro de Recursos Naturais Renováveis e não Renováveis IBAMA) e sensíveis ao espectrômetro de massas (LC-MS/MS Cromatografia líquida acoplada ao espectrômetro de massas), no período entre fevereiro de 2009 e setembro de 2010, em amostras de águas superficial e subsuperficial, peixes e sedimentos. Os ingredientes ativos (agrotóxicos) monitorados foram: acefato, atrazina, azoxistrobina, buprofezina, carbofurano, ciproconazole, clorpirifós, difeconazole, diurom, imidacloprido, malationa, metamidofós, metolacloro, metribuzim, monocrotofós, monuron, tiametoxam e triazofós. Amostras de água superficial foram coletadas a montante e a jusante da represa do Tijunqueiro; água subsuperficial em poços piezométricos perfurados no entorno da área irrigada; peixes e sedimentos foram coletados na represa do Tijunqueiro. A técnica de extração em fase sólida (SPE) foi utilizada para extrair os ingredientes ativos das amostras de água, dispersão da matriz na fase sólida (DMFS) para as amostras de sedimentos e QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para as amostras de peixes. Os métodos multiresíduos utilizados foram adequados e eficientes para a análise e quantificação por LC-MS/MS. Verificou-se que todas as curvas analíticas apresentaram coeficiente de correlação superior a 0,99 e as recuperações foram satisfatórias (70 % a 120 % de recuperação) para a maioria dos ingredientes ativos monitorados. Nas amostras de água superficial, peixe e sedimentos, não foram detectados resíduos dos ingredientes ativos monitorados e 25,7 % das amostras de água subsuperficiais apresentaram contaminação por atrazina / The importance of pesticides to the agricultural system production is indisputable, since they are part of the basics inputs, however, it is essential that they be used properly to be preserved not only the quality of the growing product, but also of their own natural resources, especially soil and water. In this study was conducted the pesticides monitoring used on crops irrigated with a central pivot in the Tijunqueiro watershed municipality of Morrinhos, state of Goias, who had potential for environmental contamination (criteria of the Environmental Protection Agency from the United States EPA, index of GUS - Groundwater Ubiquity Score, GOSS method and Brazilian Institute of Environment and Renewable Natural Resources IBAMA) and sensitive to the mass spectrometer (LC-MS/MS Liquid Chromatography coupled to mass spectrometer) on the period between February 2009 and September 2010, in samples of surface and groundwater, fish and sediment. The active ingredients (pesticides) monitored were acephate, atrazine, azoxistrobin, buprofezin, carbofuran, cyproconazol, chlorpyriphos, difenoconazol, diuron, imidacloprid, malathion, metamidophos, metolachlor, metribuzin, monocrotophos, monuron, thiamethoxan and triazophos. Surface water samples were collected upstream and downstream of the Tijunqueiro dam; groundwater in piezometric wells drilled around the irrigated area; fishes and sediments were collected in the Tijunqueiro dam, The solid phase extraction technique (SPE) was used to extract the analytes from water samples, dispersive solid phase extraction (dSPE) for the sediments samples and QuEChERS (Quick, Easy, Cheap, Effective, Rugged) for the fishes samples. Multiresidue methods used in the study were adequate and efficient for the analysis and quantifications by LC-MS/MS. Was found that all the analytical curves showed correlation coefficients greater than 0,99 and the recoveries were satisfactory (70 % a 120 % of recovery) for most of the active ingredients studied. In the surface water samples, sediments and fish were not detected residues of the active ingredients monitored and 25.7 % groundwater samples showed atrazine contamination
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Vliv chemických zdrojů znečištění na jakost povrchových vod v povodí Horní Vltavy

NEKOLNÝ, Tomáš January 2019 (has links)
The diploma thesis is focused on the issue of surface water pollution, which is one of the biggest problems of the contemporary world. The pollution of watercourses and reservoirs worsens the quality of aquatic ecosystems as well as ecosystems in their surroundings. The typical sources of surface water pollution include especially point sources (human settlements, industrial sites) and land resources (agriculture). While the point sources of pollution can be monitored, the situation is far more complicated for the field sources. In agricultural farming, the fertilizer residues, pesticides and other substances come into the groundwater and the surface water. The aim of this work is to find out the quality of surface water in the measuring profiles (river Malše), to find out the hydrological situation during the year and to evaluate the impact of chemical pollution sources influencing the quality of the surface water in the river basin.

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