1000 resultados para Reservatório de água


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We know the importance of treating water for human consumption because changes in the physicochemical and / or biological has been associated with various health problems, the quality of water intended for human consumption must meet potability standards established by governmental decree 518/2004. The aim of this study was to evaluate the quality of water supplied schools and daycare in the city of São Carlos - SP. We selected 31 schools and kindergartens, and at intervals of 3 months, two water samples taken at three different points - network, tank and fi lter - totaling 186 samples, with an interval of three months, to verify possible differences in sampling points and at different times. The samples were evaluated for the following parameters: presence of total coliform and fecal coliform / E. coli count of heterotrophic bacteria, determination of pH, fl uoride, free residual chlorine, turbidity and color. The largest number of samples outside the standard for coliform was coming from the fi lters and the network, heterotrophic bacteria in most samples was taken out of standard fi lters. In the physical-chemical analysis of samples as many non-standard pH occurred in the network, network, and fl uoride in the fi lter pair in the fi lter to free chlorine and turbidity in the reservoir. The parameter with a larger sample size was inadequate fl uoride. We need more attention to the conservation, cleaning and maintenance of building reservoirs and fi lters in schools and kindergartens of San Carlos, since the water was considered unfi t for consumption.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Este artigo apresenta um caso histórico de colapso dos solos que ocorreu durante e após o enchimento do reservatório da UHE Três Irmãos na região noroeste do Estado de São Paulo. A construção desta barragem e o subseqüente enchimento do reservatório elevaram significativamente o lençol freático, causando uma série de problemas em algumas . Trabalhos de campo e de laboratório foram realizados para determinar o potencial de risco associado às edificações existentes no local. A elevação do lençol freático foi monitorada especialmente para o estudo de recalques de edificações. São apresentados os aspectos principais do processo de colapso deflagrado na região e as conseqüências advindas de sua ocorrência, bem como, a importância da colapsibilidade na elaboração de projetos de engenharia, visando minimizar impactos em áreas urbanas.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The End of Course Work this aims, the hydrological cycle of water on our planet, and explain about its importance in the lives of living beings, finally, carry out a detailed analysis regarding the financial feasibility of implementing a system Shauer sustainable in the condominium, the first being the pickup of river water, which will use a reservoir for capitation and filtering, a reservoir for water storage filtered and pumps that will redirects it to outside faucets and toilets use in residences

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The End of Course Work this aims, the hydrological cycle of water on our planet, and explain about its importance in the lives of living beings, finally, carry out a detailed analysis regarding the financial feasibility of implementing a system Shauer sustainable in the condominium, the first being the pickup of river water, which will use a reservoir for capitation and filtering, a reservoir for water storage filtered and pumps that will redirects it to outside faucets and toilets use in residences

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No gerenciamento de recursos hídricos, a bacia hidrográfica é considerada a unidade natural de gestão. Suas características físicas definem um espaço onde a água converge para uma saída comum. O desenvolvimento integrado de uma bacia, bem como os possíveis conflitos ocasionados por demandas concorrentes do mesmo recurso, devem ser administrados respeitando esse conceito de unidade. No caso específico da bacia hidrográfica do Rio Jaguari, existe uma crescente preocupação relacionada aos usos múltiplos da água superficial. O rio Jaguari, importante afluente do Paraíba do Sul no estado de São Paulo, tem suas águas represadas para geração de energia elétrica e regularização de vazões. Nos últimos anos, tem-se constatado um crescente rebaixamento dos níveis operacionais da represa do Jaguari. Segundo estudos da sociedade civil organizada local, a tendência é de esgotamento do reservatório em poucos anos. Este trabalho aborda a questão do rebaixamento dos níveis de Jaguari através da aplicação do software DHI Mike Basin 2000. Trata-se de um simulador genérico para sistemas de recursos hídricos, de ampla aplicação. A bacia do Jaguari é representada em um modelo matemático e são simulados quatro cenários distintos de usos de água na bacia. Verifica-se que o problema é real e requer uma intervenção multi-institucional para ser solucionado.

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The reservoirs are water sources built along the fluvial basins, between rivers and dams made by concrete or earth. In Brazil they are built for different purposes, standing out the generation of energy (hydroelectric power station), flowing regulation, water reserves and flooding control, therefore they have played and still play an important role in the modern society.In the Northeastern semiarid region, they are typically used to supply cities and as a source of food.In the state of Rio Grande do Norte, the large reservoirs are intended for the same purpose.The cities settled in the riverbanks, or which have river channels crossing them, face flooding related problems. In the city of Macaíba-RN, flooding occurred systematically during the rainy season, causing great inconvenience to the local population.As product of the collective claim Tabatinga Reservoir in Jundiaí river was built, upstream of the city. Facing this background, this thesis aimed to assess the sócio-environmental quality of this reservoir.To achieve this goal, methodologies pointed to assess water quality along with the aplication of a questionnaire were used aimed to verify the quality of water and to know the perception of the residents from urban and rural área settled near to the reservoir was performed. The results showed the existence of conflicts of residents of rural communities and the presence of the reservoir, while for the city's population, the reservoir is considered not only the right solution to solve flooding in urban areas, but also as economic source for the rural population. Considering the water source assessment, this study concluded that the Tabatinga Reservoir is unfit for human use, due to the presence of metals of toxicological significance with the potential to elicit damage to the genetic material of individuals that use water from this reservoir, leading to cause serious risks to health population.

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Reservoirs are artificial ecosystems, intermediate between rivers and lakes, with diferent morphological and hydrological characteristics that can provide many important benefits to society. However, the use of this water for human consumption, watering livestock, leisure, irrigated agricultural production and pisciculture development, directly influence the increase loading of nutrients to aquatic environments and contribute to acceleration of eutrophication. Furthermore, global climate models are predicting a higher occurrence of extreme events such as floods and severe droughts, which will create hydrological stresses in lakes. In the semiarid northeast we can see the occurrence of these events, the drought of the years 2012, 2013 and 2014 was the worst drought in 60 years, according to the National Water Agency (ANA). Thus, this study aimed to evaluate the quality of the semiarid tropical water sources, identifying temporal patterns in periods with extreme hydrological events (floods and severe droughts). The study results showed that Gargalheiras and Cruzeta reservoirs presented significative changes in the limnological variables between rain and severe drought periods, with better appearance and in the most of the water quality variables in the rainy season and higher nutrientes concentrations and high electrical conductivity values in severe season, indicating decay of its quality. However, we found diferent behaviors between the reservoirs in severe drought. While Gargalheiras showed a typical behavior of the region, with high concentrations of algal biomass, indicating the worsening eutrophication, Cruzeta demonstrated a colapse in the total phytoplankton biomass, evidenced by the decrease in chla concentrations. This fact occurred because the low depth and proximity with the sediment facilited the inorganic solids resuspension and, consequently, resulted in turbid water column and light by limitation. In addition, the different behaviors between the reservoirs indicate that the responses of these environments problems such as extreme events must take into account factors such the region climate, size, depth of the reservoir and the basin characteristics.

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Droughts are climatic phenomena whose frequency has increased in the last decades and also compromised drinkable water supplies in semiarid regions. The lack of rain combined with high evaporation rates promotes a significant reduction of the volume of reservoirs in these regions. Shallower conditions favors nutrients concentration and phytoplankton overgrowth, including potentially toxic cyanobacteria blooming. Therefore, there is a tendency to the intensification of eutrophication in those reservoirs during drought periods. Phytoplankton can respond quickly to environmental conditions related to light and nutrient availability by changes in algal biomass and composition, therefore it is considered a good predictor of environmental variables. Two functional approaches - Reynolds’s Functional Groups (FG) and Kruk’s Morphologically Based Functional Groups (MBFG) - were used to assess which environmental variables were responsible for phytoplankton dynamics, in addition to compare which functional approach explains environmental changes better. This study highlights that the reduction of 90% in the volume of a tropical reservoir of Brazilian semi-arid region, as well as light limitation and nutrient increase, can promote phytoplankton overgrowth. Multivariate analyses using both functional approaches indicated a clear separation between high volumes and low volumes conditions, showing that light and nutrient availability were the main variables that better explained the combination of functional groups. The composition of phytoplankton assemblage changed from species of meso-eutrophic habitats (FG: F and J; MBFG: VI), to organisms of eutrophic and turbid environments (FG: SN and M; MBFG: VIII and VII) during shallower conditions. Both ecological approaches described properly the phytoplankton dynamics according to light and trophic state alterations related to the water volume reduction, therefore they can be considered as equivalent approaches for using in similar environments.

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Human activities alter soil features, causing the deterioration of its quality. Land use and occupation in drainage basins of water supply reservoirs can change the environmental soil quality and, thus, lead to the expansion of the soil potential of being a diffuse pollution source. In the Brazilian semiarid region, the soils are generally shallow with high susceptibility to erosion, favoring the sediment and nutrients input into the superficial waterbodies, contributing to the eutrophication process. Moreover, this region has high temperatures and high evapotranspiration rates, that are generally higher than the precipitation rates, causing a negative hydric balance and big volume losses by evaporation. The water volume reduction increases the nutrients’ concentration and, therefore, exacerbates the eutrophication process, deteriorating the water quality. Thereby, we hypothesized that the eutrophication process of semiarid reservoirs is intensified both by the extreme climatic events of prolonged drought, and by the diffuse pollution due to the basin land use and occupation. The study aimed to test whether the land use and occupation activities of the basin and the severe drought events intensify the eutrophication process of a semiarid tropical reservoir. To verify the influence of human activities carried out in the water supply of drainage basin on the soil quality and the eutrophication process, we conducted the mapping of the kind of use and occupation, as well the calculation of erosion for each activity and the soil quality evaluation of the riparian zone and water quality of the water supply. For the water analyses, the samplings were carried out monthly in the deeper point, near dam. For the soil, deformed composite samples were taken for the physical and chemical attributes analysis, according to the identified land use and occupation classes. The results showed that extreme droughts drastically reduces the water volume and elevates the nutrients concentration, contributing, thus, to a bigger degradation of water quality. Furthermore, we verified that human activities in the drainage basin promote the diffuse pollution, by increasing the soil susceptibility to erosion and nutrients contents. Summarizing, our results support the investigated hypothesis that activities of land use and occupation and extreme drought generate a combined effect that provide the intensification of eutrophication process of semiarid reservoirs.

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The mathematical modeling in the simulation of self-purification capacity in lotic environment is an important tool in the planning and management of hydric resources in hydrographic basin scale. It satisfactorily deals with the self-purification process when the coefficients of physical and biochemical processes are calibrated from monitorated water quality data, which was the main focus of this study. The present study was conducted to simulate the behavior of the parameters OD, BOD5, total phosphorus, E. coli, ammonia, nitrite, nitrate and the total metals cadmium, chromium, copper, lead and zinc in the Uberabinha’s lower course (with an approximate annual growth flow between 4-35 m3/s), in a stretch of 19 km downstream of the treated effluent release by the WWTP of the city. The modelings, on the present study, show the importance of constant water quality parameters monitoration over the water course, based on the comparison of the simulations from calibrated coefficients and coefficients obtained in the literature for the period of June until November 2015. After coefficients calibration, there were good adjustments between simulated and measured data for the parameters OD, BOD, Ptotal, ammonia and nitrate and unsatisfactory adjust for the parameters nitrite and E. coli. About the total metals, the adjustments were not satisfactory on the reservoir’s vicinity of the Small Hydropower Plant Martins, due the considerable increase of the bottom sediment in lentic region. The greatest scientific contribution of this study was to calibrate the decay coefficient K and the quantification of the release by the fund S of total metals in watercourse midsize WWTP pollutant load receptor, justified by the lack of studies in the literature about the subject. For the metals cadmium, chromium, copper, lead and zinc, the borderline for K and S calibrated were: 0.0 to 13.0 day-1 and 0.0 to 1.7 g/m3.day; 0.0 to 0.9 day-1 and 0.0 to 7.3 g/m3.day; 0.0 to 25.0 day-1 and 0.0 to 1.8 g/m3.day; 0.0 to 7.0 day-1 and 0.0 to 40.3 g/m3.day; 0.0 to 30.0 day-1 and 0.0 to 70.1 g/m3.day.

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This study aimed to describe the spatial and temporal patterns of variation in trophic state and its relation with the structure and dynamics of planktonic community of a large reservoir located in semi-arid tropical region of Northeast Brazil. The reservoir Armando Ribeiro Gonçalves is the biggest reservoir of the Rio Grande do Norte State and is responsible for about 53% of all surface water accumulated in the State. The samples of water and plankton were taken monthly in 10 points distributed throughout the longitudinal axis of the reservoir and over a full hydrological cycle. The samples were collected to determine concentrations of total phosphorus, total nitrogen, chlorophyll a and suspended solids (fixed and volatile) and for determining the composition and abundance of phytoplanktonic and zooplanktonic species. During the study period, the reservoir was characterized as eutrophic and there was no trend of increasing the trophic state of the reservoir in the period of drought. The concentrations of total phosphorus and suspended fixed solids decreased towards the dam while the N:P ratios increased in the same direction due to the reduction in the phosphorus concentrations and relative constancy in the nitrogen concentrations. The N:P ratios observed were indicative of greater limitation by phosphorus than by nitrogen. However, as concentrations of both nutrients were high and the water transparency was very low, with secchi depth usually lower than one meter, it seems likely that the planktonic primary production of the reservoir is more limited by the availability of light than the availability of nutrients. High nutrient concentrations coupled with low availability of light may explain the continuing dominance of filamentous cyanobacteria such as Cylindrospermopsis raciborskii in the plankton of the reservoir.These cyanobacteria are potentially toxic and pose a serious environmental problem because it compromises the water quality for public supply, recreation and fishing when present in high densities as in this study. The mesozooplankton of the reservoir was dominated by the calanoid Notodiaptomus cearensis and the cladoceran Diaphanosoma spinulosum. In general, the structure of zooplankton community seems to be particularly influenced by the spatial variation of cyanobacteria. The results of the regression analyses show that both the chlorophyll a concentrations and the cyanobacteria biovolume were more strongly correlated with the nitrogen than with phosphorus and that the water transparency was more strongly correlated with algal biomass than with other sources of turbidity. The maximum load of phosphorus to attain the maximum permissible concentration of total P in the reservoir was estimated in 63.2 tonnes P/ year. The current external P load to the reservoir is estimated in 324 tonnes P / year and must be severely reduced to improve the water quality for water supply and allow the implementation of aquaculture projects that could contribute to the socio-economic development of the region

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The aims of this study were: i) assessing the trophic state of the Mendubim reservoir (semi-arid, Rio Grande do Norte, Brazil; 05° 38 99,0 S 36°55 98,0 W) based on chlorophyll-a, total phosphorus and nitrogen concentrations and water transparency; ii) relating the patterns of temporal variation of zooplankton and phytoplankton to the trophic state of the reservoir and iii) investigating the carrying capacity of the reservoir for cage fish farming. The samplingwas done monthly from July 2006 to July 2007 in three stations at the reservoir: next to the dam (barrage), in the central region and in the mouth of the main tributary. The abiotic and biotic variables analyzed were: Secchi depth, volatiles and fixed suspended solids, chlorophyll-a, total phosphorus and nitrogen, TN:TP ratio and mesozooplankton and phytoplankton composition and biomass. The results showed that the reservoir can be considered as mesotrophic with mean concentrations of total nitrogen, phosphorus and chlorophyll-a equal to 1711, 1 μg.L-1, 30,8 μg.L-1 and 5,62 μg.L-1 respectively. The Cyanophyceae class was the most representative in terms of density, with the presence of potentially toxic species such as Microcystis aeruginosa, Planktothrix planctonica, Cylindrospermopsis raciborskii, Aphanizomenon sp. ,Aphanocapsa delicatissima and Pseudanabaena acicularis. Among the zooplankton, the genus Notodiaptomus presented the largest biomass values. Overall, our results show that the light limitation should explain the weak relationship between chlorophyll-a and total phosphorus and nitrogen concentrations. We concluded that the water of Mendubim reservoir is suitable for intensive fish cage aquaculture. Based on the carrying capacity calculations for this reservoir, we found that the maximum sustainable yield of tilapias in cages in the reservoir is 126 ton per year assuming a factor of food conversion of 1.5: 1.0 and a phosphorus content in the fish food of 1%

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Top-down (grazing) and bottom-up (nutrient, light) controls are important in freshwater ecosystems regulation. Relative importance of these factors could change in space and time, but in tropical lakes bottom-up regulation has to been appointed as more influent. Present study aimed to test the hypothesis that phytoplankton growths rate in Armando Ribeiro reservoir, a huge eutrophic reservoir in semi-arid region of Rio Grande do Norte state, is more limited by nutrient available then zooplankton grazing pressure. Bioassay was conduced monthly from September (2008) to August (2009) manipulating two levels of nutrients (with/without addition) and two level of grazers (with/without removal). Experimental design was factorial 2X2 with four treatments (X5), (i) control with water and zooplankton from natural spot ( C ), (ii) with nutrient addition ( +NP ), (iii) with zooplankton remove ( -Z ) and (iv) with zooplankton remove and nutrient addition ( -Z+NP ). For bioassay confection transparent plastic bottles (500ml) was incubate for 4 or 5 days in two different depths, Secchi`s depth (high luminosity) and 3 times Secchi`s depth (low luminosity). Water samples were collected from each bottle in begins and after incubates period for chlorophyll a concentration analysis and zoopalnktonic organisms density. Phytoplankton growths rates were calculated. Bifactorial ANOVA was performance to test if had a significant effect (p<0,005) of nutrient addition and grazers remove as well a significant interaction between factors on phytoplankton growths rates. Effect magnitude was calculated the relative importance of each process. Results show that phytoplankton growth was in generally stimulated by nutrient addition, as while zooplankton remove rarely stimulated phytoplankton growth. Some significant interactions happening between nutrient additions and grazers remove on phytoplankton growth. In conclusion this study suggests that in studied reservoir phytoplankton growth is more controlled by ascendent factors than descendent