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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.
21

Fosforprocesser i Bornsjön, Stockholms reservvattentäkt - dynamisk massbalansmodellering med LakeMab / Phosphorus processes in Bornsjön, Stockholm's reserve water source - modeling with LakeMab

Dimberg, Peter January 2010 (has links)
Bornsjön är Stockholms viktigaste reservvattentäkt och kan tillgodose staden med dricksvatten i flera månader om Mälaren skulle slås ut. Det är därför viktigt att Bornsjön håller en god vattenkvalitet. Under de senaste åren har vattenkvaliteten avseende totalfosfor i Bornsjön försämrats. Hög belastning av fosfor kan leda till övergödning i en sjö. När en sjö är övergödd uppstår ökad syreförbrukning som kan leda till syrebrist. Vid syrebrist frigörs fosfor från sediment och det blir större näringstillgång som bidrar till mer övergödning. Övergödning beror ofta på utsläpp från punktkällor, till exempel från avloppsvattenutsläpp, men kan även bero på diffusa utsläpp från jordbruksmark och skog inom avrinningsområdet. Syftet med examensarbetet var att förstå vilka fosforprocesser som är viktiga för Bornsjönsom ekosystem och med den dynamiska massbalansmodellen LakeMab utvärdera olika realistiska åtgärder för att minska belastningen av totalfosfor. Marken runt Bornsjön ägs av Stockholm Vatten och med resultaten från detta arbete ska Stockholm Vatten få olika förslag på vilka åtgärder som bör prioriteras. Resultat från andra kända modeller har även jämförts med LakeMabs resultat. Studien visade att det är möjligt att reglera belastningen av totalfosfor på Bornsjön genom till exempel införande av vallodling, minskning av åkerareal och genom minskade utsläpp från enskilda avlopp. Dessa olika åtgärder kan kombineras för ökad effekt. Det är även möjligt att sänka totalfosforkoncentrationen i sjön genom att sänka sjöns pH-värde. Detta är dock en åtgärd som inte rekommenderas på grund av att en förändring av det naturliga pH-värdet påverkar ekosystemet. För att i framtiden kunna göra liknande studier med mer tillförlitliga resultat bör provtagningsprogrammet i dikena utökas, speciellt vid kraftig nederbörd då fosforläckaget från marken är större. / Lake Bornsjön is Stockholm’s most important reserve water source and can supply the city with drinking water for several months in case Mälaren would be polluted. Thus it is important to maintain the water quality of Bornsjön. In the last years the quality of the drinking water has in reference to total phosphorus in Bornsjön degraded. High load of phosphorus leads to eutrophication in lakes. When a lake is eutrophicated the respiration increases, which may lead to a lack of oxygen in the water. At reduced conditions of oxygen, phosphorus will be released from the sediments which lead to an increased eutrophication. Eutrophication is often the result of anthropogenic point sources, for example waste water treatment plants, but can also be due to diffuse sources like agricultural and forests within the catchment area. The purpose with this Master degree project was to understand which phosphorus processesare important for Bornsjön as an ecosystem and with the dynamic mass balance model LakeMab evaluate different realistic actions to decrease the load of total phosphorus. Most of the catchment area around Bornsjön is owned by Stockholm Vatten and the aim of this project is to recommend Stockholm Vatten which actions should be prioritized. Also, results from other models have been compared with the results from LakeMab. This study showed that it is possible to regulate the load of total phosphorus to Bornsjön, for example with ley farming, less agricultural area and decreased load from individual sewage systems. These different actions can be combined for an increased effect. It is even possible to lower the concentration of the total phosphorus in the lake by decreasing its pH-value. However, this action is not recommended because a change of the natural pH will affect the ecosystem. To make similar studies in the future with more reliable results it is important to extend the sample scheme for the ditches, especially at occasions with high precipitation which leads to increased phosphorus leakage from the soil.
22

Geração da série histórica de vazão por meio do modelo SMAP: subsídio para o plano de manejo da bacia do Rio Grande de Ubatuba. / Generating streamflow records through the smap model: a contribution for the elaboration of the management plan for the Rio Grande watershed, Ubatuba.

Viviane Coelho Buchianeri 13 April 2004 (has links)
A bacia hidrográfica do Rio Grande de Ubatuba (26Km2) encontra-se quase que totalmente recoberta com vegetação nativa da Mata Atlântica, e grande parte está inserida no interior do Parque Estadual da Serra do Mar. O Rio Grande é um manancial estratégico para o município, pois abastece 88% da população, que recebe água tratada de serviço público. Com o propósito de conhecer a potencialidade hídrica do manancial de forma a subsidiar tecnicamente a elaboração do Plano de Manejo para a bacia, o presente estudo foi conduzido para gerar a série histórica de vazão, usando o Modelo SMAP (Soil Moisture Accounting Procedure) e analisar o balanço entre a disponibilidade e a demanda de água. Com apenas quatro anos incompletos de dados fluviométricos e com a série histórica de 67 anos de dados de precipitação, foi possível calibrar os parâmetros e validar o modelo com uma correlação de 0,838 entre as vazões estimada e observada e por último gerar a serie histórica de vazão. Com a série histórica de vazão gerada foi feita a análise temporal do balanço entre a disponibilidade e demanda que permitiram identificar a insuficiência hídrica para atender a demanda para abastecimento público ou para manutenção dos processos ecológicos do manancial, considerando três aspectos: a flutuação da população, a ocorrência de anos hídricos secos e, mesmo nos anos hídricos normais, ocorrência de períodos de meses secos prolongados. Com base na análise conjunta dos resultados, algumas ações consideradas compatíveis para a prevenção de possível escassez de água no futuro foram formuladas, visando proporcionar melhor qualidade de vida à população. / The Rio Grande Watershed of Ubatuba (26km2 ) is almost completely covered with native Atlantic Rainforest vegetation, and a large part is within the bounds of the Serra do Mar State Park. The Rio Grande is a strategic water source for the municipality, supplying 88% of the population demand with treated water via a public service. In order to analyse the water potential of the source and to acquire technical information for the preparation of the Watershed Management Plan, this study was carried generate streamflow historic data, using the SMAP (Soil Moisture Accounting Procedure) model. This, in turn, permitted to analyse the balance between demand and availability of water.With only 4 years of incomplete streamflow data and 67 years of rainfall data, it was possible to calibrate the parameters and validate the model with a correlation of 0.838 between the estimated and observed flows, and finally produce a streamflow history.To produce the streamflow history, a time analysis was carried out with the balance between availability and demand, which allowed the identification of water shortages for public supply, as well as for the maintenance of the stream ecological processes, considering the following three aspects: population fluctuations, the occurrence of drought years and, even in normal years, the occurrence of extended periods of drought.
23

Avaliação ambiental das unidades da paisagem do Parque Municipal Serra da Areia e sua Zona de Amortecimento em Aparecida de Goiânia-GO / Environmental assessment of the landscape unit of the Parque Municipal Serra da Areia and its Buffer Zone in Aparecida de Goiânia - GO

Mendonça Neto, Wilson Lopes 25 August 2014 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-10-21T18:53:07Z No. of bitstreams: 2 Dissertação - Wilson Lopes Mendonça Neto - 2014.pdf: 6260941 bytes, checksum: 7518d54f3139d936b42606076ba0c076 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-21T18:53:19Z (GMT) No. of bitstreams: 2 Dissertação - Wilson Lopes Mendonça Neto - 2014.pdf: 6260941 bytes, checksum: 7518d54f3139d936b42606076ba0c076 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-21T18:53:19Z (GMT). No. of bitstreams: 2 Dissertação - Wilson Lopes Mendonça Neto - 2014.pdf: 6260941 bytes, checksum: 7518d54f3139d936b42606076ba0c076 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-08-25 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In the context of various urban agglomerations, and in particular the Metropolitan Region of Goiania - RMG, a major challenge that presents today is the availability of water sources, its qualities and also the distribution of water resources for public water supplies. The water supply for RMG is primarily carried out by the company Sanitation Goiás S / A - Saneago and secondarily by independent municipal systems. Goiânia (1.333.767 inhabitants), Aparecida de Goiânia (500.619 inhabitants) and Trindade (107.966 inhabitants) are the most populous municipalities and the sum of its inhabitants (1.915.952) represents more than 85% of the population of RMG. These three municipalities have in common the fact that they are served by a single integrated system of water supply formed by watershed areas of Ribeirão João Leite, Meia Ponte River, Córrego Samambaia, Córrego do Arrozal and Córrego Lajes. This work focused about one of the watershed areas that make up this integrated system. The area corresponds to the Conservation Unit, Parque Municipal Serra da Areia, which is located entirely in the city of Aparecida de Goiânia and, too, its Buffer Zone, that covers areas of the municipalities of Aparecida de Goiania, Goiania, Hidrolandia, and Aragoiânia, and Abadia de Goiás. The aimed was conduct an Environmental Assessment. To this end, observations and analysis were supported by concepts developed within the Study of Landscapes in Physical Geography and methodology Pressure-State-Response utilized for preparation and analysis of environmental indicators. In order to support the organization, the analysis and synthesis of spatial data included in the survey GIS tools were used. From the application of these tools were prepared illustrative resources as thematic maps, infographics, schematic illustrations and tables in order to best represent the consolidated results and the process of organization and execution of the research were developed. The study area was investigated through four main channels: a survey of literature sources on the study area; interviews with various actors involved in the management, planning and the exploitation of resources of the area; acquisition, digital processing of satellite images for extraction and analysis of data and geographic information of the area, which also involved conducting fieldwork for spot verification of such information; obtaining, organizing and analyzing secondary data provided by the National Research by Household Sample, the Brazilian Institute of Geography and Statistics. From the adopted procedures were realized the mapping of landscape units of the study area, over which the environmental assessment was performed. Data were summarized in an index of environmental quality, expressed by a map of environmental quality, from which it was possible to identify and evaluate various environmental contexts. Results demonstrated different levels of changing landscapes and, consequently, the environmental framework. The main consequence related to the identified scenario is the risk of exhaustion and / or pollution of water resources on which they depend are currently more than 100,000 households in Aparecida de Goiânia. / No contexto de diversas aglomerações urbanas e, em específico da Região Metropolitana de Goiânia - RMG, um dos grandes desafios que se apresenta na atualidade diz respeito à disponibilidade de áreas de mananciais, a manutenção de suas qualidades e, ainda, a distribuição dos recursos hídricos por meio de sistemas públicos de abastecimento. Na RMG o abastecimento de água é realizado, principalmente, pela empresa de Saneamento de Goiás S/A – SANEAGO e, secundariamente, por sistemas independentes municipais. Goiânia (1.333.767 habitantes), Aparecida de Goiânia (500.619 habitantes) e Trindade (107.966 habitantes) são os municípios mais populosos e a soma de seus habitantes (1.915.952) corresponde a mais de 85% da população da RMG. Esses três municípios possuem em comum o fato de serem atendidos por um único sistema integrado de abastecimento de água que é formado por áreas de mananciais do Ribeirão João Leite, do Rio Meia Ponte, do Córrego Samambaia, do Córrego Arrozal e do Córrego Lajes. Este trabalho versou sobre uma das áreas de mananciais que compõem esse sistema integrado. A área corresponde a Unidade de Conservação, Parque Municipal Serra da Areia, que se localiza totalmente no município de Aparecida de Goiânia e, também, sua Zona de Amortecimento, que abrange áreas dos municípios de Aparecida de Goiânia, Goiânia, Hidrolândia, Aragoiânia e Abadia de Goiás. Teve-se como objetivo a realização de uma Avaliação Ambiental da área. Para tal, as observações e análises foram amparadas por concepções desenvolvidas no âmbito do Estudo das Paisagens em geografia física e na metodologia Pressão-Estado-Resposta desenvolvida para elaboração e análise de indicadores ambientais. Foram utilizadas ferramentas SIGs, a partir das quais foram elaborados recursos ilustrativos como mapas temáticos, infográficos, ilustrações esquemáticas, quadros e tabelas a fim de melhor representar os resultados consolidados e o processo de organização e execução da pesquisa. A área de estudo foi investigada por meio de quatro vias principais: o levantamento de fontes bibliográficas sobre a área de estudo; realização de entrevistas com diversos atores envolvidos com a gestão, o planejamento e a exploração dos recursos da área; aquisição, tratamento digital de imagens de satélite para extração e análise de dados e informações geográficas da área, o que envolveu, também, a realização de trabalhos de campo para verificação in loco dessas informações; obtenção, organização e análise de dados secundários disponibilizados pela Pesquisa Nacional por Amostra de Domicílios, do Instituto Brasileiro de Geografia e Estatística. A partir dos procedimentos adotados realizou-se o mapeamento das Unidades da Paisagem da área de estudo, sobre as quais, foi realizada a avaliação ambiental. Os dados foram sintetizados em um índice de qualidade ambiental, expresso por um mapa de qualidade ambiental, a partir do qual foi possível identificar e avaliar diversos contextos ambientais. Os resultados demonstraram diferentes níveis de alteração das paisagens e, consequentemente, do quadro ambiental. A principal consequência relacionada ao cenário identificado é o risco de esgotamento e/ou contaminação dos recursos hídricos, dos quais dependem atualmente mais de 100.000 domicílios de Aparecida de Goiânia.
24

Studie úpravny vody z povrchového zdroje / Study of water treatment plant from surface source

Inwald, Petr January 2021 (has links)
The first part of the thesis deals with water sources and methods of drinkable water treatment. This section describes the technologies used for two-stage water treatment from a surface source. The second part deals with study of the new drinking water treatment plant from a surface source for Adamov town. The work documents the current state of the existing water treatment plant and describes used technology with a design flow Q = 30 l s-1. In the next part of thesis is design of two variations of new technological line with a design flow Q = 10 l s-1. The first variation is one-stage water treatment with pressure filters as the main separation stage. Two-stage water treatment is designed for the second variation, in which the first stage of separation are clarifiers and the second stage are pressure filters. Thesis includes drawing documentation of designed pressure filters and clarifiers, technological and height scheme of both variations.
25

The Influence of Anthropogenic Development of Water on Coyotes and Kit Foxes in the Great Basin and Mojave Deserts

Hall, Lucas Keith 13 March 2013 (has links) (PDF)
Anthropogenic provisioning of water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence distribution, competition dynamics, and behavior of native species. To elucidate the potential influences of water developments on native species, we tested hypotheses concerning the occurrence and behavior of native kit foxes (Vulpes macrotis). First, we tested the indirect effect of water hypothesis (IEWH) which proposes that water developments negatively affect the arid-adapted kit fox by enabling a water-dependent competitor (i.e., coyote; Canis latrans) to expand distribution in arid landscapes. We tested the two predictions of the IEWH (i.e., coyotes will visit areas with water more frequently and kit foxes will avoid coyotes) and evaluated relative use of water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) water and monitored visitation by canids to scent stations and water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. There was no correlation between visits to scent stations by coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. The intense visitation to water by kit foxes in Mojave challenges our understanding that this species does not readily drink water. Our results did not support the IEWH in the Great Basin or Mojave Deserts for these two canids. Second, we tested three hypotheses that have been proposed to explain spatial variation in vigilance behavior. The predator-vigilance hypothesis (PVH) proposes that prey increase vigilance where there is evidence of predators. The visibility-vigilance hypothesis (VVH) suggests that prey increase vigilance where detection of predators is impeded or visibility is obstructed. The refuge-vigilance hypothesis (RVH) proposes that prey may perceive areas with low visibility (greater cover) as refuges and decrease vigilance. We evaluated support for these hypotheses using the kit fox, a solitary carnivore subject to intraguild predation, as a model. From 2010 to 2012, we used infrared-triggered cameras to record video of kit fox behavior at water developments in the Mojave Desert. The RVH explained more variation in vigilance behavior of kit foxes than the other two hypotheses (AICc model weight = 0.37). Kit foxes were less vigilant at water developments with low overhead cover (refuge) obstructing visibility. Based on our results, the PVH and VVH may not be applicable to all species of prey. Solitary prey, unlike gregarious prey, may use areas with concealing cover to maximize resource acquisition and minimize vigilance.
26

Cobertura florestal e custo do tratamento de águas em bacias hidrográficas de abastecimento público: caso do manancial do município de Piracicaba. / Forest cover and the cost of water treatment in municipal watershades: the case of the Piracicaba municipal watershed.

Reis, Lúcia Vidor de Sousa 26 October 2004 (has links)
A sociedade necessita de indicadores capazes de medir a susceptibilidade ao risco de degradação de um manancial de abastecimento público. O percentual de cobertura florestal de uma bacia hidrográfica pode ser utilizado como um dos indicativos na avaliação da qualidade de um manancial de abastecimento público. O custo do tratamento de águas provenientes de bacias hidrográficas com diferentes percentuais de cobertura florestal é um componente que pode subsidiar discussões sobre a importância da cobertura florestal em mananciais de abastecimento público, como recurso ambiental a ser priorizado pelo poder público e exigido pela sociedade, tendo em vista os benefícios econômicos e de minimização de riscos à saúde humana. O trabalho determinou os custos do tratamento da água proveniente de bacias hidrográficas com diversos percentuais de cobertura florestal através da análise das características operacionais de diversas Estações de Tratamento de Água (ETAs) e suas respectivas captações. Para seis dos sete sistemas e ETAs estudadas, o custo específico com produtos químicos na ETA eleva- se com a redução do percentual de cobertura florestal da bacia de abastecimento. Não se pretendeu situar e associar a localização das áreas de cobertura florestal a outros fatores como, por exemplo, a susceptibilidade do solo à erosão ou ao percentual de área florestada situada em APP’s. Considerando-se o enfoque do trabalho sobre a qualidade de mananciais de abastecimento público e a relevância do episódio de rejeição do rio Piracicaba no ano 2000 como principal manancial de abastecimento público do município de mesmo nome, em decorrência da perda de qualidade de suas águas, dos altos custos do tratamento e da impossibilidade de garantir água de consumo humano de qualidade , o trabalho teve por objetivo também analisar as perspectivas para a qualidade das águas do rio Corumbataí, novo manancial eleito para Piracicaba. Utilizou-se como recurso a análise de dados de caracterização física das bacias e sócio-econômica dos municípios das bacias dos rios Piracicaba e Corumbataí, e da qualidade das águas dos rios Piracicaba e Corumbataí. O estudo faz uma reflexão sobre o atual arranjo de instituições públicas, suas atribuições legais e ferramentas para a aplicação de leis e implementação de ações de planejamento regional nas bacias dos rios Corumbataí e Piracicaba. / The Society needs to be able to check when a water source for public supply is about to reach a degradation level. The percentage off forest covered in the watershed can be used as one of the indicators to measure the quality of a public water source. The cost of water treatment from different water supply areas containing different percentage of soil forest cover, is a component that can be brought into discussions about the importance of the forest cover in drinking water public supply areas, as an environmental natural resource, to be prioritized by the Authorities, and mandatory by the Society, heading to both economical benefits and the human health risks minimization. This work has determined the costs of water treatment from water supply areas with different percentages of natural forest cover, analysis of all operating data of all Treatment Water Stations (ETAs), as well as their water sources. For six out of seven studied systems and ETAs, the specific cost with chemical products in one ETA increases with the reduction of the known portion of rain forest for the watershed. Certainly this study was not intended to try to associate the forest location areas to other factors, as for example, the erosion soil characteristic or to the portion of forest cover, located in riparian areas. Considering the focus of this work about the public supply of drinking water and the recent episode of the Piracicaba river rejection as the main water supply for the Region in year 2000, because of the low level quality of its water, the high treatment costs, and the impossibility to make feasible to count on it to distribute good quality water, this work had also the purpose of analyzing the perspectives for the Corumbataí river, to be elected as the main source of water supply for Piracicaba. Socio-economic of all cities along the river basins of Piracicaba and Corumbataí has been studied. Besides the organization of all administrative offices in charge with the problem, their legal functions and possible available tools to plan and to work properly, has also been analyzed.
27

Contribuição ao conhecimento do meio físico da região do lixão de São Carlos - SP, através de estudos geológicos, geofísicos, topográficos e químicos / Contribution to environment\'s knowledge of the Sao Carlos - SP waste dump area - by geological, geophysical, topographical and chemical studies

Álvares, Cyro Martins Bicudo 13 June 2000 (has links)
O lixão da cidade de São Carlos foi colocado, aproximadamente por dezessete anos, em uma boçoroca formada em região sedimentar, sobre os arenitos da Formação Botucatu, sem nenhuma espécie de controle prévio, quanto a possibilidade de contaminação do meio físico e, especialmente da água subterrânea. Dada essa possibilidade de contaminação do aqüífero profundo, uma série de estudos são feitos no local, desde a década de 80. Este trabalho vem somar-se aos diversos outros na tentativa de aprofundar o conhecimento das condições em que se encontra o meio físico na região do lixão. Fazendo parte de um projeto maior este trabalho procurou, utilizando as ciências de geologia, geofísica, topografia e química, dar novos elementos e interpretações a esse conhecimento. Geologicamente, detectamos e avaliamos a presença de camadas penetrativas, hidraulicamente menos condutivas, como areias siltosas e, muito provavelmente, arenito silicificado ou diabásio em profundidade, o que poderia fazer que a contaminação não atingisse o aqüífero profundo. Para isso utilizamos o mapeamento geológico e a geofísica em três de suas técnicas: caminhamento elétrico, sondagens elétricas verticais e perfilagem de poços. Quimicamente, avaliamos a contaminação das águas subterrâneas em relação ao sentido do fluxo. / For seventeen years, Sao Carlos\' solid wastes were placed in a gully formed in a sedimentary area, on the Botucatu Formation (friable sandstone and sands), without any form of control to prevent the contamination of the environment and, especially, of the ground water. Thanks to the possibility of contamination of the deep water source, a series of studies have been made in the area since the eighties. These studies were just another attempt, along with severaI others, to increase the knowledge of the environmental conditions surrounding the waste dump area. Being part of a greater project, different sciences were used such as geology, geophysics, topography and chemistry, in order to obtain new elements and a more acurate interpretation to the existing knowledge. Geologicaly, we detected a less hydraulicaly conductive silty sand layers and, probably, silicificated sandstone layers or diabase sill which could protect the deep water sources from being contaminated. Geologic mapping and geophysical techniques such as electric surveys and well logs were performed during the process. Chemically, we evaluated the ground water contamination in relation to the flow\'s direction.
28

Application of Relative Response Factors in Solid-Phase Micro Extraction GC/MS for the Determination of Polycyclic Aromatic Hydrocarbons in Water

Schebywolok, Tomi 13 July 2018 (has links)
Solid-phase microextraction (SPME) coupled with gas chromatography/mass spectrometry (GC/MS) is routinely used to analyze polycyclic aromatic hydrocarbons (PAHs) in water. A common SPME-GC/MS approach quantifies target analytes using isotopically labeled standards (IISs); one IIS is needed for each target analyte. This approach is challenging, even prohibitive since IISs are often expensive; moreover, they are generally not available for each analyte of interest. This study developed a novel SPME-GC/MS approach for the quantification of PAHs in water. The new method, which employs only a small number of IISs, uses relative response factor (RRF) (i.e., analyte corresponding to IIS) to quantify PAHs in water. Possible matrix dependency of RRFs values was examined using water that was modified concerning different physical-chemical characteristics (i.e., ionic strength, pH, suspended solids, humic acid, and biological organic carbon represented by hemoglobin). The results revealed that RRFs are not noticeably affected by changing ionic strength and pH; the other three parameters did affect the RRFs. However, the results also showed that the effect is minimal when the solution is dilute (i.e., low concentrations of suspended solids, humic acid or hemoglobin). Relatively stable RRFs for dilute water solutions indicates that this approach can be used for routine quantification of water that does not contain prohibitive amounts of suspended solids, humic acid, and biological organic matter. The developed method was employed to quantify trace levels of PAHs in three different types of water, namely river water, well water, and bottled water. PAH levels in every kind of water were less than 100 ng/L level (i.e., 0.1 ppb). Analyses of spiked water samples containing 2 ng PAHs revealed correlations between calculated RRFs and the physical-chemical properties of the PAHs investigated (i.e., vapor pressure, boiling point, octanol/water partition coefficient, octanol/air partition coefficient, GC retention time). This implies that RRFs for PAHs not examined in this study can be predicted. Overall, the results presented herein constitute a meaningful contribution to the development of SPME-GC/MS methods for quantitative analysis of PAHs and other chemicals in dilute aqueous solutions. Moreover, the development of methods that alleviate the need for IISs corresponding to each target analyte.
29

Cobertura florestal e custo do tratamento de águas em bacias hidrográficas de abastecimento público: caso do manancial do município de Piracicaba. / Forest cover and the cost of water treatment in municipal watershades: the case of the Piracicaba municipal watershed.

Lúcia Vidor de Sousa Reis 26 October 2004 (has links)
A sociedade necessita de indicadores capazes de medir a susceptibilidade ao risco de degradação de um manancial de abastecimento público. O percentual de cobertura florestal de uma bacia hidrográfica pode ser utilizado como um dos indicativos na avaliação da qualidade de um manancial de abastecimento público. O custo do tratamento de águas provenientes de bacias hidrográficas com diferentes percentuais de cobertura florestal é um componente que pode subsidiar discussões sobre a importância da cobertura florestal em mananciais de abastecimento público, como recurso ambiental a ser priorizado pelo poder público e exigido pela sociedade, tendo em vista os benefícios econômicos e de minimização de riscos à saúde humana. O trabalho determinou os custos do tratamento da água proveniente de bacias hidrográficas com diversos percentuais de cobertura florestal através da análise das características operacionais de diversas Estações de Tratamento de Água (ETAs) e suas respectivas captações. Para seis dos sete sistemas e ETAs estudadas, o custo específico com produtos químicos na ETA eleva- se com a redução do percentual de cobertura florestal da bacia de abastecimento. Não se pretendeu situar e associar a localização das áreas de cobertura florestal a outros fatores como, por exemplo, a susceptibilidade do solo à erosão ou ao percentual de área florestada situada em APP’s. Considerando-se o enfoque do trabalho sobre a qualidade de mananciais de abastecimento público e a relevância do episódio de rejeição do rio Piracicaba no ano 2000 como principal manancial de abastecimento público do município de mesmo nome, em decorrência da perda de qualidade de suas águas, dos altos custos do tratamento e da impossibilidade de garantir água de consumo humano de qualidade , o trabalho teve por objetivo também analisar as perspectivas para a qualidade das águas do rio Corumbataí, novo manancial eleito para Piracicaba. Utilizou-se como recurso a análise de dados de caracterização física das bacias e sócio-econômica dos municípios das bacias dos rios Piracicaba e Corumbataí, e da qualidade das águas dos rios Piracicaba e Corumbataí. O estudo faz uma reflexão sobre o atual arranjo de instituições públicas, suas atribuições legais e ferramentas para a aplicação de leis e implementação de ações de planejamento regional nas bacias dos rios Corumbataí e Piracicaba. / The Society needs to be able to check when a water source for public supply is about to reach a degradation level. The percentage off forest covered in the watershed can be used as one of the indicators to measure the quality of a public water source. The cost of water treatment from different water supply areas containing different percentage of soil forest cover, is a component that can be brought into discussions about the importance of the forest cover in drinking water public supply areas, as an environmental natural resource, to be prioritized by the Authorities, and mandatory by the Society, heading to both economical benefits and the human health risks minimization. This work has determined the costs of water treatment from water supply areas with different percentages of natural forest cover, analysis of all operating data of all Treatment Water Stations (ETAs), as well as their water sources. For six out of seven studied systems and ETAs, the specific cost with chemical products in one ETA increases with the reduction of the known portion of rain forest for the watershed. Certainly this study was not intended to try to associate the forest location areas to other factors, as for example, the erosion soil characteristic or to the portion of forest cover, located in riparian areas. Considering the focus of this work about the public supply of drinking water and the recent episode of the Piracicaba river rejection as the main water supply for the Region in year 2000, because of the low level quality of its water, the high treatment costs, and the impossibility to make feasible to count on it to distribute good quality water, this work had also the purpose of analyzing the perspectives for the Corumbataí river, to be elected as the main source of water supply for Piracicaba. Socio-economic of all cities along the river basins of Piracicaba and Corumbataí has been studied. Besides the organization of all administrative offices in charge with the problem, their legal functions and possible available tools to plan and to work properly, has also been analyzed.
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Contribuição ao conhecimento do meio físico da região do lixão de São Carlos - SP, através de estudos geológicos, geofísicos, topográficos e químicos / Contribution to environment\'s knowledge of the Sao Carlos - SP waste dump area - by geological, geophysical, topographical and chemical studies

Cyro Martins Bicudo Álvares 13 June 2000 (has links)
O lixão da cidade de São Carlos foi colocado, aproximadamente por dezessete anos, em uma boçoroca formada em região sedimentar, sobre os arenitos da Formação Botucatu, sem nenhuma espécie de controle prévio, quanto a possibilidade de contaminação do meio físico e, especialmente da água subterrânea. Dada essa possibilidade de contaminação do aqüífero profundo, uma série de estudos são feitos no local, desde a década de 80. Este trabalho vem somar-se aos diversos outros na tentativa de aprofundar o conhecimento das condições em que se encontra o meio físico na região do lixão. Fazendo parte de um projeto maior este trabalho procurou, utilizando as ciências de geologia, geofísica, topografia e química, dar novos elementos e interpretações a esse conhecimento. Geologicamente, detectamos e avaliamos a presença de camadas penetrativas, hidraulicamente menos condutivas, como areias siltosas e, muito provavelmente, arenito silicificado ou diabásio em profundidade, o que poderia fazer que a contaminação não atingisse o aqüífero profundo. Para isso utilizamos o mapeamento geológico e a geofísica em três de suas técnicas: caminhamento elétrico, sondagens elétricas verticais e perfilagem de poços. Quimicamente, avaliamos a contaminação das águas subterrâneas em relação ao sentido do fluxo. / For seventeen years, Sao Carlos\' solid wastes were placed in a gully formed in a sedimentary area, on the Botucatu Formation (friable sandstone and sands), without any form of control to prevent the contamination of the environment and, especially, of the ground water. Thanks to the possibility of contamination of the deep water source, a series of studies have been made in the area since the eighties. These studies were just another attempt, along with severaI others, to increase the knowledge of the environmental conditions surrounding the waste dump area. Being part of a greater project, different sciences were used such as geology, geophysics, topography and chemistry, in order to obtain new elements and a more acurate interpretation to the existing knowledge. Geologicaly, we detected a less hydraulicaly conductive silty sand layers and, probably, silicificated sandstone layers or diabase sill which could protect the deep water sources from being contaminated. Geologic mapping and geophysical techniques such as electric surveys and well logs were performed during the process. Chemically, we evaluated the ground water contamination in relation to the flow\'s direction.

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