940 resultados para Evento hidrológico
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In semiarid region of northeast Brazil, the majority of reservoirs used for public supply has suffered degradation of water quality affected by diffuse pollution from agricultural and livestock areas of the watershed and by hydrologic regime peculiar to the region, characterized by a rainy season with higher volumes stored in reservoirs and a dry season with a reduction in water level due to high evaporation and increase of eutrophication. The Dourado reservoir, located in Currais Novos city, semiarid region of Rio Grande do Norte state, is one example of a water supply reservoir that can have degradation of water quality and impracticability of their use, due to the high external input of nutrients from non-point sources of watershed during the rainy season and increasing of eutrophication due to decrease the stored volume during the dry period. This study aimed to investigate and quantify diffuse pollution and the hydrologic regime of semiarid region in order to establish standards regarding the water quality of Dourado reservoir. The study period was between the months of May 2011 to March 2012. The diffuse pollution was quantified in terms of watershed from the mass balance of phosphorus in the reservoir, as in relation to areas under different types of land use within the riparian zone of the reservoir from the assessment of soil chemical properties and losses of phosphorus in each area. The influence of hydrological regime on water quality of the reservoir was evaluated from the monthly monitoring of the morphometric, meteorological and limnological features throughout the study period. The results showed that the reservoir has received a high load of phosphorus coming from the drainage basin and presents itself as a system able to retain some of that load tributary, giving an upward trend of the eutrophication process. Diffuse pollution by nutrients from areas under different types of land use within the riparian zone of the reservoir was higher in areas under the influence of livestock, being this area considered a potential diffuse source of nutrients to the reservoir. Regarding the water regime during the rainy season the reservoir was characterized by high concentrations of nutrients and small algal biomass, while in the dry season the reduction of volume and increase of the water retention time of the reservoir, contributing to the excessive growth algal biomass, favoring an increase in eutrophication and deterioration of water quality. In synthesis the water quality of Dourado reservoir is directed by diffuse pollution coming from the drainage basin and the hydrological regime of the peculiar semiarid region, where the rainy season is characterized by high input of allochthonous compounds from the tributaries and erosion of the soil in the reservoir riparian zone, and the dry season characterized by reducing the storage volume due to high evaporation, high residence time of water and consequent degradation of water quality due to the increase of eutrophication process
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The potentially toxic cyanobacterial blooms in water bodies are spread across the globe, resulting in the loss of water quality and adverse effects on human health. In arid and semiarid regions, the hydrologic regime characterized by an annual cycle of drought and rain, change the volume and the retention time of the reservoir. Such changes affect the limnological characteristics and causing changes in composition and biomass community of cyanobacteria. The reservoir Cruzeta (Zmax = 8.7 m) is a eutrophic water supply source located in the semiarid tropical (Northeast Brazil). Raised the hypothesis that the hydrological regime of semi-arid tropical is a determining factor in the availability of resources in eutrophic water sources, which influences the composition of dominant species of cyanobacteria. The aim of this study was to analyze the changes in biomass and species composition of cyanobacteria for two annual hydrological cycles and evaluate factors drivers. The study was divided into five distinct periods (dry 2010, rain 2011, dry 2011, rain 2012, dry 2012). The dominant group found in all periods was Cyanobacteria (99% of total biomass), which contributed to the low diversity. The filamentous species Cylindrospermopsis raciborskii was present at both points in almost every study. The colonial species Microcystis panniformis and Sphaerocavum brasiliensis dominated only in periods with lower volumes of water. The diatoms contribute more to the biomass during the period of severe drought. The point near the dam (P1) had phytoplankton biomass larger than the point near the tributary (P2). The dominant species of colonial cyanobacteria lasted until the overflow in P1, and P2 this dominance was until the first rains. The redundancy analysis indicated that physical factors such as light availability and water level were the main factors driving the seasonal succession of phytoplankton. The composition of phytoplankton in spring was alternated by species of filamentous cyanobacteria in conditions of poor stability of the water column, such as Cylindrospermopsis raciborskii, and colonial species under conditions of high stability of the water column, such as Microcystis panniformis and Sphaerocavum brasiliensis. The extremes of torrential rains and severe droughts, governed by the hydrological regime of the semi-arid region led to the availability of resources in the watershed, directing the spatial and temporal dynamics of phytoplankton in the reservoir Cruzeta
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In the semiarid region of northeastern of Brazil, the reservoirs are vulnerable to water level seasonal fluctuations, they re related to the hydrological cycle. The rain periods are irregular and there are long periods of drought that increases eutrophication process. That happens because of the water level s reduction and nutrient concentration. The Boqueirao, located in northeastern Brazil , is a mesotrophic reservoir. The reservoir is naturally susceptible to deterioration of water quality. This happens because of the potential diffuse sources arising from the use and occupation of the basin, associated with shallow soil caatinga biome and highly vulnerable to erosion. This study aimed to analyze the influence of the use and occupation of the area around and the water quality of the watershed. A study of the area around the Boqueirão was performed, taking the potentially polluting activities. Limnological variables were monitored monthly in 3 points of the reservoir to assess the water quality. Was evidenced an event of prolonged drought, with rainfall below the historical average for the year of study. By the index of water quality, the watershed was classified as " good " during the whole year of 2012. According to the trophic index adopted the reservoir is characterized as mesotrophic. The main anthropogenic impacts identified in the soil were arboreal selective logging, mining, diffuse contribution of residues from agricultural and livestock activities. The lack of precipitation and the degradation of the surrounding area, affect negatively the water quality, requiring immediate control to prevent degradation of the watershed . Although there wasn t a majority polluting activity in the region. The total of several impacting activities, the high susceptibility of the soil and the selective clearing of caatinga vegetation can accelerate the natural process of eutrophication in the water body
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In most cultures, dreams are believed to predict the future on occasion. Several neurophysiological studies indicate that the function of sleep and dreams is to consolidate and transform memories, in a cyclical process of creation, selection and generalization of conjectures about the reality. The aim of the research presented here was to investigate the possible adaptative role of anticipatory dreams. We sought to determine the relationship between dream and waking in a context in which the adaptive success of the individual was really at risk, in order to mobilize more strongly the oneiric activity. We used the entrance examination of the Federal University of Rio Grande do Norte (UFRN) as a significant waking event in which performance could be independently quantified. Through a partnership with UFRN, we contacted by e-mail 3000 candidates to the 2009 examination. In addition, 150 candidates were approached personally. Candidates who agreed to participate in the study (n = 94) completed questionnaires specific to the examination and were asked to describe their dreams during the examinaton period. The examination performance of each candidate in the entrance examination was provided by the UFRN to the researcher. A total of 45 participants reported dreams related to the examination. Our results show a positive correlation between performance on the examination and anticipatory dreams with the event, both in the comparison of performance on objective and discursive, and in final approval (in the group that not dreamed with the exam the rate of general approval, 22,45%, was similar to that found in the selection process as a whole, 22.19%, while for the group that dreamed with the examination that rate was 35.56%). The occurrence of anticipatory dreams reflectes increased concern during waking (psychobiological mobilization) related to the future event, as indicated by higher scores of fear and apprehension, and major changes in daily life, in patterns of mood and sleep, in the group that reported testrelated dreams. Furthermore, the data suggest a role of dreams in the determination of environmentally relevant behavior of the vigil, simulating possible scenarios of success (dream with approval) and failure (nightmares) to maximize the adaptive success of the individual
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Inserted in the schedule for Christmas celebration in the city of Natal, capital of the state of Rio Grande do Norte, Brazil, the spectacle so called Auto de Natal mixes the Christmas story of Jesus birth with cultural and natural heritage of the state, making possible the integration of professionals from various fields, such as: literature, theater, dance and music. Important for local identity, Auto de Natal integrates elements of intangible heritage in the state. In this context, the research analyzed the perceptions of those who were involved in the production, presentation and organization of the event, planned to be culturally attractive to tourism. For this, it was used the descriptive and exploratory method, making use of documental, bibliographic and field researches. It was applied qualitative techniques to the interpretation of the interviews, while it was applied quantitative techniques to analyze the questionnaires. The research has discovered that Auto de Natal has the potential to add value to Cultural Tourism, diversifying the tourism product. The research has also observed that most of the respondents recognized Auto de Natal as intangible heritage, and concluded that the Christmas theme, which is alluding to the nomenclature of destiny, needs to be well-done to attract more tourists to experience the Natal in Natal
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INTRODUCTION. Cardiovascular diseases (CVD) are the main cause of death in Brazil.OBJECTIVE. To evaluate the frequency of CVD risk factors In a population attending a health education community event.METHODS. Retrospective study that included 428 completed forms with clinical and demographic information of volunteers attending a public event, in May, 2006. Data were expressed by means and standard deviation or proportions and compared by Student's t test or Chi-square test. Associations between Arterial Hypertension (AH), Diabetes Mellitus (DM) and clinical variables were analyzed by multinomial logistic regression. Significance level was p<0.05.RESULTS. Mean age was 57 +/- 14years, and women represented 58% of the total population. The main cardiovascular risk factors were AH (39.5%), DM (15.4%) and dyslipidemia (25.89%). The frequency of unawareness about these risk factors was respectively 8.4%, 17.5% and 33.1%.. Family history of CVD was reported by 41% while only 67% reported having any information about DM or dyslipidemia. Among obese individuals (IMC >= 30 Kg/m2, 27.3% of the population), systolic blood pressure (133 +/- 16mmHg), diastolic blood pressure (84 +/- 11.5mmHg) and casual glycemia (124 +/- 52.5mg/dl) were higher when compared to non-obese (p<0.05). There was a significant association between obesity and dyslipidemia (p=0.04). Age and IMC were independently associated with AH and DM.CONCLUSION. The high frequency of modifiable cardiovascular risk factors in this population suggests the need for educational programs to promote primary prevention, mainly for the elderly and overweight. [Rev Assoc Med Bras 2009; 55(5): 606-10]
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Um evento extremo de precipitação ocorreu na primeira semana do ano 2000, de 1º a 5 de janeiro, no Vale do Paraíba, parte leste do Estado de São Paulo, Brasil, causando enorme impacto socioeconômico, com mortes e destruição. Este trabalho estudou este evento em 10 estações meteorológicas selecionadas que foram consideradas como aquelas tendo dados mais homogêneos do Que outras estações na região. O modelo de distribuição generalizada de Pareto (DGP) para valores extremos de precipitação de 5 dias foi desenvolvido, individualmente para cada uma dessas estações. Na modelagem da DGP, foi adotada abordagem não-estacionaria considerando o ciclo anual e tendência de longo prazo como co-variaveis. Uma conclusão desta investigação é que as quantidades de precipitação acumulada durante os 5 dias do evento estudado podem ser classificadas como extremamente raras para a região, com probabilidade de ocorrência menor do que 1% para maioria das estações, e menor do que 0,1% em três estações.
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Pós-graduação em História - FCHS
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Pós-graduação em Ciência da Informação - FFC
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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A influência do fenômeno da friagem nas variáveis meteorológicas e nos fluxos de energia e CO2 , foi realizada numa área de floresta próxima à região de Ji-Paraná, Rondônia, durante o mês de junho de 2001. A friagem ocasionou uma diminuição de 35% no valor da temperatura do ar. Notou-se uma redução de 75 W.m-2, na radiação solar incidente, associada à nebulosidade presente em decorrência da penetração da massa de ar fria. Conseqüentemente, tanto o fluxo de calor sensível (H) quanto o de calor latente (LE), apresentaram uma diminuição no seu valor médio diário, apresentando uma diferença em relação aos dias normais de 8 e 34%, respectivamente. A concentração de CO2 permaneceu constante, sem apresentar o aumento comum durante a noite, devido à condição de vento forte típica da friagem. Em situação normal o fluxo médio durante o dia de CO2 (-2,44 mmol m-2 s-1) foi menor que durante os dias de friagem (-5,78 mmol m-2 s-1); enquanto que os fluxos médios noturnos foram +1,77mmol m-2 s-1 e +2,83mmol m-2 s-1 durante situações de dias normais e de friagem, respectivamente.
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Este trabalho buscou quantificar algumas alterações no ciclo hidrológico da Amazônia propiciadas pelo desmatamento da região, principalmente devido à faixa conhecida como "Arco do Desmatamento". Neste sentido, foram realizados experimentos numéricos utilizando o modelo BRAMS (Brazilian Regional Atmospheric Modeling System) tendo o submodelo de vegetação dinâmica GEMTM (General Energy and Mass Transport Model) a ele acoplado. Foram investigados os impactos causados pelo Arco do Desmatamento atual em relação à floresta intacta, bem como as futuras modificações, causados pelo avanço do desmatamento até o ano de 2050. Como condições de contorno na superfície para o modelo BRAMS, foram usados cenários oriundos de modelos empíricos de desmatamento para os anos de 2002 e 2050. Os resultados mostraram que o avanço do Arco do Desmatamento até 2050 tem uma complexa relação com as variáveis analisadas. Por exemplo, a precipitação apresentou distribuição espacial heterogênea, com áreas de anomalias positivas e negativas que se mostraram coerentes com as anomalias de outras variáveis, como a evapotranspiração e a divergência de umidade. Também foram encontradas algumas áreas que evidenciaram as possíveis influências dos grandes rios e topografia da região sobre essa precipitação. Os balanços de radiação e energia também foram afetados pelo desmatamento, sendo que grande parte das alterações é devido à mudança do albedo da superfície, a qual ocorre com a substituição da floresta pela pastagem. Quanto às alterações propiciadas pelo Arco do Desmatamento atual em relação à floresta intacta, foi observado que todas as variáveis foram afetadas, entretanto a maioria dos impactos ainda é localizada sobre a área mais afetada pelo desmatamento, diferentemente dos resultados encontrados para o cenário de 2050, onde as modificações já se dão a nível regional.
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A presente dissertação desenvolveu um Sistema de Alerta de Enchentes para a Cidade de Marabá, localizada na confluência dos rios Itacaiúnas e Tocantins, a 440 km da cidade de Belém, capital do Estado do Pará. O Sistema de Alerta de Enchentes foi desenvolvido com base no modelo hidrológico MOD-4B incorporado a um Sistema de Informações Geográficas. Esse sistema permite prever as variações do nível do Rio Tocantins ao longo do ano, de modo a acompanhar a evolução da cheia com antecedência de 4 dias, o que torna possível uma ação eficiente da defesa civil. O modelo de previsão utilizou como referência as réguas linimétricas localizadas nos rios Tocantins e Araguaia nas cidades de Carolina e Conceição do Araguaia, distantes aproximadamente 225 e 270 km, respectivamente, da cidade de Marabá. O sistema utiliza o software de geoprocessamento ArcView 3.3, que teve implementada uma interface desenvolvida através da linguagem de programação orientada a objetos Avenue, com a finalidade de rodar o aplicativo do modelo hidrológico. O uso de menus e janelas customizados do sistema possibilitou o acesso a dados espaciais e tabelas de dados relacionais e/ou banco de dados cadastral, além de módulos de análise espacial e de visualização de dados geográficos em um Sistema de Informações Geográficas (SIG), possibilitando a previsão de enchentes na forma de mapas, tabelas e relatórios com a indicação das áreas inundadas para os períodos de 4, 3, 2 e 1 dia de antecedência do evento de enchente. O Sistema permitiu identificar os imóveis e as ruas atingidos, e possibilitará através de levantamentos futuros quantificar a população afetada e os prejuízos causados pelo desastre, facilitando que a defesa civil execute planos de ação para enfrentamento eficiente antes, durante e depois da ocorrência da enchente.