909 resultados para Águas superficiais


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The studies of this work aimed to determine the labile fractions of manganese (Mn) in natural and drainage water samples collected around the Osamu Utsumi uranium mine, located in the municipality of Caldas, south-central region of Poços de Caldas- MG, using the technique of diffusion gradient in thin films (DGT). The DGT devices were mounted with Chelex-100 resin, polyacrylamide-agarose hydrogel (conventional porosity) and cellulose acetate membrane. The device were deployed up to 48 hours in six water samples collected from different areas around the uranium mine (075, 076, 022-E, 025-E, 014, and 041). The DGT devices immersed in each sample were gradually removed after 4, 8, 12, 24 and 48 hours. The pH of the samples ranged from 3.0 to 10.5, which influenced the lability and the sampling of the analyte by the Chelex-100 resin. The results showed a linear relationship between accumulated mass and sampling time (immersion curve) for samples 014 and 025-E (pH between 6 and 8) suggesting the ability of the DGT technique for sampling the analyte. The results obtained for samples 075 and 076 (pH<5) and samples 041 and 022-E (pH around 10) were characterized by nonlinear relationships. The values obtained by DGT were compared with Solid Phase Extraction (SPE) technique using Chelex-100. For samples 014 and 025-E, there was a good agreement between the results obtained by both techniques

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The lack of proper planning in intervention works of runoff water on rural properties and rural public roads leads to economic damage and loss of environmental quality. The impact of the action without technical base is soil erosion, siltation of water sources, loss of the quality and availability of water, invalidating areas for cultivation and livestock. The conservation of headwaters requires beyond regeneration of the environmental characteristics the repair and management of the degraded watercourse in order to control erosion. This graduate work in Environmental Engineering from Universidade Estadual Paulista Julio de Mesquita Filho - UNESP Presidente Prudente proposes a headwater recuperation and management in rural area of Álvares Machado municipality, São Paulo State, through the method of deep drainage applied to the case of a rural road near the outcrop of water. This technique consists in the installation of draining structures in sub-areas of the road surface, or sub-gutter and/or in the platform border in order to conduct the underground flow of water and reduce the loss of sediment in water flow. Therefore, was performed a historic study of use and occupation of land in the municipality of Álvares Machado, portraying transformations of the landscape caused by human action. Geology, geomorphology, pedology and hydrogeology data were collected from the study area in order to establish the conditions that led into the current situation of degradation and formulate an effective intervention strategy for civil works

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Os estudos hematológicos das diferentes espécies de peixes são de interesse ecológico e fisiológico, auxiliando na compreensão da relação entre as características sanguíneas, a filogenia, a atividade física, o hábitat e a adaptabilidade dos peixes ao ambiente. No experimento realizado foram testados os efeitos de águas contaminadas em parâmetros hematológicos de peixes da espécie Prochilodus lineatus, em períodos de coleta de 7 e 20 dias, nos quais o sangue foi coletado com seringas heparinizadas, foram montadas lâminas de esfregaço , as quais foram coradas pelo corante de Leishman. Estas lâminas foram analisadas e fotografadas com o auxílio de um microscópio óptico Leica, no qual foram feitas contagens totais de células brancas e contagens diferenciais de trombócitos e leucócitos, para a análise estatística. O grupo exposto ao Lago Azul apresentou uma elevação no número de leucócitos e no total de células brancas, evidenciando que os contaminantes químicos do ambiente estavam atuando de forma semelhante a um antígeno no corpo do animal fazendo com que suas células de defesa se proliferassem. Quanto ao grupo exposto ao detergente, observou-se que após os vinte dias de experimento ocorreu uma diminuição no número de trombócitos. Tais resultados evidenciam que a variação no número de leucócitos apresentou-se como um indicador de poluição ambiental e que os detergentes biodegradáveis podem em certo tempo de exposição ocasionar um déficit em funções vitais de peixes como à coagulação e a prevenção contra infecções, eventos ligados diretamente com os trombócitos. A maioria dos vertebrados aquáticos possui brânquias, estruturas especializadas nas trocas gasosas e responsáveis por grande parte das trocas iônicas. Este órgão acaba por absorver grande parte das substâncias presentes na água, que ao caírem na...(Resumo completo, clicar acesso eletrônico abaixo)

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The DGT technique has been used to determine and better understand the dynamics and bioavailability of metals in the sea near to marine outfalls. In this work, the DGT was assessed for the determination of Cd, Pb, Cu, Zn and Ni in marine water samples from Potiguar Basin in its conventional aspect (binding agent, Chelex-100 and diffusive agent: Diffusive polyacrylamide gel (D) and restrictive (R)) and determination of Pb and Cd through its alternative aspect (binding agent: Saccharomyces cerevisiae immobilized in agarose gels and diffusive agent: 3MM Chromatography Paper). The deployment curves for long periods of immersion in the sample, showed a good linear correlation for the conventional aspect to Zn (D: R²=0.9586, R: R²=0.9444), Ni (D: R²=0.9789, R: R²=0.9286) and Cu (D: R²=0.764, R: R²=0.8143), and alternative to Pb (R²=0.9228) and Cd (R²=0.9673). The results of the organic and inorganic composition analysis in conventional aspect, showed that for every element there is no significant fraction of organic compounds in the sample. In addition, considering the alternative aspect, the comparison of obtained and expected masses suggests that some of the Pb is not labile and that the main retention mechanism of Pb for S. Cerevisiae occurs through ion exchange

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This work is proposed to evaluate the potential risk of an inert landfill in the city of Rio Claro (SP), and also suggest a source for the contamination. The study was proposed because it is known that there were legal technicalities greetings to guarantee the quality of groundwater. Given the requirements of the Environmental Company of São Paulo (CETESB) were installed monitoring wells in the area; sampled to groundwater and its contamination was found. In addition, we analyzed the main characteristics of the area, the arrangement and characteristics of the waste, the local geology and the hydrogeological system, so that I could find the source of contaminants, and predict the direction of dispersion even in groundwater. At the end of the work presents conclusions, recommendations and proposals for mitigating action

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The main objective of this study is to determine the activity of Po-210, Pb-210 and gross alpha/beta radioactivity in groundwater collected in Botucatu, municipality of the São Paulo state, Brazil. Samples were collected in wells to perform the radiochemical analysis. Most wells are registered in DAEE, Sabesp or CPRM. The activity of polonium was obtained by the method of alpha spectrometry, held in LABIDRO at UNESP, Rio Claro. All samples showed radioactivity values below the maximum allowed by WHO, that are: gross alpha radioactivity = 0,5 Bq/L, gross beta radioactivity = 1,0 Bq/L, Po210 = 0,2 Bq/L and Pb210 = 0,1 Bq/L. The results of hydrochemical analysis were compared with the 1469 Ordinance of the Health Ministry, and all values are bellow the maximum allowed. The data also allowed obtain the samples classification using the Piper diagram. The samples AAB, Quinta do Manacás, Faz. Quatro Irmãs, Sesi, Sitio São José and ITE are classified as calcic bicarbonate; the samples Staroup and Caio are potassic; the samples Banespa and BTC are bicarbonate and mixed interms of dissolved cations; Sitio das Palmeiras sample is sodium bicarbonate; the sample Faz. São Paulo is chlorinated calcic; the sample Sítio Btu-Pardinho chlorinated and mixed interms of dissolved cations

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Concerns about the quality of groundwater have been continuously rising, considering its importance for the public water supply in the State of São Paulo, and even more due to the impact that anthropic action has been causing to the original quality of that natural resource. It is extremely relevant to identify the contamination focuses along the aquifers of the State of São Paulo. This report aims to evaluate nitrates and fluorides concentrations along the aquifers present in the state, in order to identify places where change in the quality of groundwater is observed, through the comparison between measured concentrations and reference values, such as: “Intervention Value” (maximum allowed value) and “Alert Value” (attention required value). To perform this research, a full compilation and organization has been done on chemical analysis data from the “Sistema de Informações de Águas Subterrâneas - SIDAS”, made available by the “Divisão de Procedimentos de Outorga – DPO” of the “Departamento de Água e Energia Elétrica – DAEE”. This work has made possible the build-up of a database composed by 6,860 wells, with analytical data ready to be interpreted, containing information about water pH, electrical conductivity, hardness and chloride, iron, fluoride, nitrogen, nitrates and total dissolved solids concentrations. This database shows concentration data for nitrates (6,157 wells) and fluoride (3,316 wells). From this information, maps for nitrates and fluorides concentration distributions have been made, by each aquifer and each “Unidade de Gerenciamento de Recursos Hídricos – UGRHI”, which has enabled the identification of wells where the concentrations of these chemical compounds exceeds the reference values. Concerning nitrates, these analysis indicated the existence of contamination sources from rural and urban zones, mostly present in the west region... (Complete abstract click electronic access below)

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A rápida expansão do espaço urbano no Brasil ocorreu e continua ocorrendo, geralmente, de forma desordenada e sem perspectivas imediatas de ordenação das práticas de uso e ocupação do solo. O planejamento da ocupação do espaço urbano, baseado na racionalidade capitalista, embora englobe fundamentos interdisciplinares, na prática tem sido realizado dentro de um âmbito mais restrito do conhecimento, desconsiderando aspectos fundamentais dessa dinâmica. Essa situação tem resultado em grandes transtorno e custos para a sociedade e para o meio ambiente, atingindo diretamente os sistemas de drenagens urbanos e resultando no crescimento dos eventos de cheia. Assim, o planejamento urbano vem buscando alternativas que possibilitem o alcance do desenvolvimento urbano sustentável. Neste sentido, este trabalho objetiva avaliar qualitativamente a implantação reservatórios de detenção implantados no alto curso da sub-bacia do Alto Tietê, de modo a avaliar os problemas apresentados através da realização de um inventário dos avanços atingidos na incorporação destas medidas no gerenciamento dos sistemas de drenagem nesta subbacia.

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Geophysics studies in areas impacted by petroleum derivatives describe abnormalities of both low and high electrical resistivity (the opposite of electrical conductivity), confirmed as contaminant phase by chemical analysis: this contradiction can be explained by degrading processes that naturally occur and create sub products that can change the environment conductivity. Monitoring the variation of the parameters mentioned serves as a comparative basis to the variation in geoelectrical parameters, which identified the correlation between the same contaminant parameters and the difference between their behavior studied apart, as well as its relations with the biodegradation process. The results are applied to the fuel distribution and storage sectors, leading to the diagnosis and monitoring of possible groundwater contamination scenarios, and the knowledge of the area exposure time to the contaminant, besides the better remediation alternative and impacts control. Among some conclusions, the most significant are the decrease in conductivity over time, so as the increase in Eh value in the gasoline contaminated tank, as well as the decrease in the pH value in the second tank with ethanol, which can be attributed to its degradation. Comparing the variations in both tanks, it is evident that Eh, pH and electrical conductivity do not behave temporally in a similar way, although some correlations between Eh and pH can be related.

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The success in implementing an embryo transfer program derives from many factors. The embryo recovery rate is one of the most important factors, and allows the transfer to the recipient mare. This rate comes from a group of elements such as donor´s characteristics, collection date, reproductive management, semen quality, technician skill. Mainly because of the great importance of this direct interference on the results of an embryo recovery program, this study aimed to review the factors involved in embryo recovery rates in donor mares during an embryo transfer, suggesting some ways of improving these results

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Cassava wastewater, generated during cassava processing, is a highly polluting and toxic waste. This study aimed to assess the relationship of cassava treatment efficiency in two aerobic sequencing batch reactors, cylindrical plastics (31cm height x 9cm diameter), with 2.0 liters capacity and 1.5 liters of work volume, a ratio of diameter and height of the liquid 1:2.5, with a running time of 24 hours and stoppage aeration for 16 hours with average feed of 2,500 and 6,000 mg COD. L -1. COD, pH, SVI and F/M were analyzed. The results obtained in the two reactors showed an average reduction of 94.1% and 76.8% organic content, respectively; pH values showed a rising in the output pH values compared to entry ones; SVI values obtained: 54.1 mL/g, 99.3 mL/g, respectively in a F/M ratio values worked out of 0.4 d-1 and 1,1 d-1 , respectively. The results demonstrated that the process has generated considerable saving in energy consumption compared to traditional continuous systems, was efficient and did not affect the efficiency overly of the reactor.

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A contaminação do solo por metais potencialmente tóxicos constitui um dos principais problemas ambientais. Por meio da lixiviação e percolação das águas, esses metais podem ser mobilizados e vir a contaminar mananciais superficiais e subterrâneos, comprometendo sua qualidade. A biodisponibilização desses metais para as plantas e, a partir dessas, para o homem é outro desfecho negativo dessa situação. O cádmio é um elemento tóxico. Os teores encontrados nos solos costumam não oferecer riscos. Porém, esses teores são potencializados pela utilização de fertilizantes. O níquel pode ser carcinogênico em doses elevadas. Sua presença em fertilizantes fosfatados proporciona maiores concentrações do metal no solo. É amplo o registro sobre efeitos do excesso desses metais, tanto em plantas, quanto em animais e no ser humano. O manganês é um dos elementos mais abundantes na crosta terrestre e se encontra largamente distribuído em solos, sedimentos, rochas, água e materiais biológicos. Contrariamente aos dois metais anteriores, esse micronutriente é um elemento essencial ao ser humano. Sua carência causa inúmeras enfermidades, por outro lado, seu excesso também. Nesse caso, poucos são os relatos sobre o assunto. Nesse estudo foram utilizados métodos de extração de metais de fertilizantes e se constatou que, quando presentes, os metais cádmio e níquel apresentaram concentrações proibitivas o que é motivo de preocupação e demonstra a falta de controle sobre a indústria de insumos agrícolas. Para o manganês não há parâmetros orientadores com limites de teores, mas com certeza, são necessários trabalhos nesse sentido para se evitar seu consumo indiscriminado.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)