797 resultados para saltos aquáticos
Resumo:
The artifi cial eutrophication is one of the biggest t h reat for the quality of aquatic ecosystems in the whole world. The expectations for the future climatic scenarios in arid and semi - arid regions are intense and frequent droughts enhancing the risk of eutrophicati on and cyanobacterial blooms. Restoration techniques of eutrophic lakes were proposed to reduce nutrient loading and improve the water quality. A successful technique used in temperate regions is the biomanipulation by benthivorous fish removal . Our hypoth esis is that the benthivorous fish removal reduces phytoplankton total biomass and change the composition of phytoplankton functional groups, improving water quality. The aim of the study was evaluate the impact of biomanipulation on phytoplankton function al groups and in the water quality. We applied the technique of biomanipulation in the artificial lake ESEC, in a semi - arid region of Brazil and analyzed the physical and chemical variables and the dynamic of phytoplankton functional groups monthly during November 2012 to August 2013. With the removal of benthivorous fish we observed a significant increase of the euphotic depth, phytoplankton richness and the recruitment of green algae (groups F and J ), indicators of good water quality. However, we did not observe significant differences on total phosphorous concentration and on phytoplankton biomass and diversity. The drought effect in the region during the study was evident , promoting a drastic reduction on water level which influenced the availability of resource and affected phytoplankton community before the biomanipulation. To evaluate the effect of severe drought on the dynamic of phytoplankton functional groups and test if the drought periods are favorable to dominance of cyanobacterial groups, we stu died two artificial neighbors lakes (ESEC and Pocinhos) in a semi - arid tropical region during May 2012 to February 2013. We observed a temporal differentiation of biotic and abiotic variables caused by drought. Both lakes presented reduction of 2 meters of water level and increase on conductivity, turbidity, nutrients concentration and a reduction on water transparency, during the severe drought. The deeper lake (Pocinhos) increased phytoplankton total biomass and presented cyanobacterial functional group d ominance (group S N ) and the shallower lake (ESEC) reduced phytoplankton total biomass and presented dominance of mixotrophic and flagellate functional groups (groups W 1 e W 2 ). Summarizing, the knowledge of the effects of benthivorous fish removal in semi - a rid tropical lakes still unknown and this study had limitations caused by the impact of drought. Thus, it is necessary a long term monitoring to investigate the real effects of biomanipulation on the functioning of the studied ecosystems. Otherwise, period s of drought could have opposite effects (increase or reduction) on total biomass and composition of phytoplankton functional groups. Drought not always leads to dominance of cyanobacterial groups.
Resumo:
The textile effluents are a complex mixture of many pollutants that contain high organic loads, severe color and toxic compounds. The high concentration of the textile effluent may cause increased chemical demand (COD) and biochemical (BOD) of oxygen, elevated temperature, acidity or alkalinity, causing damage and environmental problems. In addition to representing a serious threat to human health such effluent is also quite toxic to most aquatic organisms. And for this reason, one must meet the concentration limits for emission sources and sewage system. This study aimed to investigate the performance of electrochemical treatment of a textile effluent for the removal of color, turbidity, dissolved oxygen (DO) and dissolved organic matter by investigating the influence of experimental parameters such as the electrocatalyst materials (Ti/Pt and Ti/Pt-SnSb) and current density in order to compare their efficiency, energy consumption and cost. The dye Novacron Blue CD (NB) was employed in synthetic solution, while the dyes Remazol Yellow 3RS (RY 3RS) Remazol Red RR Gran (RR-RR Gran) and Navy Blue CL-R (NB CL-R) were used to generate simulated textile effluent laboratory. The results showed that the application of electrochemical oxidation process favors the elimination of color effectively independent the electrocatalytic material and current used, as well as treated effluent. However, the influence of electrocatalytic material was crucial to reduction of the organic matter in all cases.
Resumo:
Reservoirs are artificial ecosystems intermediate between rivers and lakes widely used in the Brazilian semiarid region as a way to provide water supply due to the said region’s water scarcity. The use of water from these supply sources for multiple uses, along with occupation and utilization of its riparian zone without proper management, directly influences the increased nutrient flow into aquatic environments, there with contributing to the acceleration of eutrophication. The semi-arid region is characterized by peculiar weather conditions, such as severe evaporation, high temperatures with little variation throughout the year and long water residence time, making it susceptible to prolonged drought occurrence, which tends to concentrate the nutrients in reservoirs, which favors the development of eutrophic conditions. Moreover, it is common soil use and occupation by carrying out activities with potential environmental impact on natural resources such as agriculture, livestock farming and lack of sanitation. The aim of this study is both to evaluate the water quality of the Cruzeta Reservoir, located in the semiarid region of Rio Grande do Norte, during a prolonged drought period, and assess the quality of its riparian zone soil under different uses, by monitoring physical-chemical variables. Along the prolonged drought, high levels of turbidity, suspended solids, nutrients and chlorophyll a were verified as present, therefore featuring low water quality. In the riparian zone of Cruzeta Reservoir, the areas under use of agriculture and livestock farming appeared as one of the main diffuse sources of nutrients to the said reservoir, featuring the highest levels of phosphorus and nitrogen in the soil, originated from decomposition of animal excreta and from the use of fertilizers, creating a tendency to increased eutrophication of such water supply source. The indicators of water and soil quality are useful for monitoring and evaluating the conservation status of natural resources, allowing the control and mitigation of the reservoir eutrophication process. This study confirmed the hypothesis that the reduction of water level, resulting from prolonged drought event, aggravates the symptoms of eutrophication; and also that using the soil under severalways modifies the physic chemical properties of the soil, having livestock farming and agriculture as the usages with greatest potential towards yielding P and N to the aquatic environment.
Resumo:
Organic dyes have been widely used in various branches of dyeing industries. These compounds are known to be very toxic, mutagenic, cancinogenic only cause aesthetic pollution and irreversible damage to aquatic ecosystems and human health. Are recalcitrant contaminants due to its high stability and resistance to photobleaching and bio. Given this context, the search for technologies that can minimize the effects of such pollutants is required. In recent decades the Electrochemical Oxidation Process Advanced (PEOAs) based on the generation of strongly oxidizing species (radicals ●OH) offer promising approaches for the prevention of problems caused by industrial effluents. This study analyzed the degradation and mineralization of textile dyes and the study of a real effluent in order to assess the feasibility of PEOAs: Electro-Fenton (EF), Photo Electro-Fenton (PEF) and anodic oxidation (AO), and these methods still was studied the Solar Fotoelectro-Fenton (SPEF) in a pre-pilot plant, in order to study the electrochemical treatment on an industrial scale. In the study has compared the effect of PEOAs in the removal of color, TOC and decay kinetics of degradation of the compounds, and also for using the Congo Red (CR) SPEF studies were performed mineralization current efficiency (MCE). The best results are given to the treatment of the PEF for all the studied dyes. From the results it was possible to choose the PEF as the most effective and promising for application of treatment when compared to other methods of treatment, and prove from SPEF that the process can be used in industrial scales, since this method PEF has been improved and solar irradiation replaced the UVA lamp.
Resumo:
Organic dyes have been widely used in various branches of dyeing industries. These compounds are known to be very toxic, mutagenic, cancinogenic only cause aesthetic pollution and irreversible damage to aquatic ecosystems and human health. Are recalcitrant contaminants due to its high stability and resistance to photobleaching and bio. Given this context, the search for technologies that can minimize the effects of such pollutants is required. In recent decades the Electrochemical Oxidation Process Advanced (PEOAs) based on the generation of strongly oxidizing species (radicals ●OH) offer promising approaches for the prevention of problems caused by industrial effluents. This study analyzed the degradation and mineralization of textile dyes and the study of a real effluent in order to assess the feasibility of PEOAs: Electro-Fenton (EF), Photo Electro-Fenton (PEF) and anodic oxidation (AO), and these methods still was studied the Solar Fotoelectro-Fenton (SPEF) in a pre-pilot plant, in order to study the electrochemical treatment on an industrial scale. In the study has compared the effect of PEOAs in the removal of color, TOC and decay kinetics of degradation of the compounds, and also for using the Congo Red (CR) SPEF studies were performed mineralization current efficiency (MCE). The best results are given to the treatment of the PEF for all the studied dyes. From the results it was possible to choose the PEF as the most effective and promising for application of treatment when compared to other methods of treatment, and prove from SPEF that the process can be used in industrial scales, since this method PEF has been improved and solar irradiation replaced the UVA lamp.
Resumo:
Eutrophication is the most common cause of water quality degradation in the world. This process occurs by excessive nutrients inputs, nitrogen and phosphorus, to the aquatic systems resulting in algal and cyanobacterial blooms. In shallow lakes these effects are pronounced due to the higher interaction of the lake with watershed, air and sediment. There are innumerous restoration techniques of eutrophied lakes with a range of successful results but there is only one case of successful lake restoration in Brazil: Paranoá Lake in Brasília city. The Brazilian semiarid region has many artificial lakes, named açudes, which are mostly eutrophic and shallow lakes. The eutrophication in these lakes is reported and the phytoplankton community is dominated by potentially toxic cyanobacteria species, mainly Cylindrospermopsis raciborskii. The aim of this thesis is to test techniques for water quality management which can be easily applied in Brazilian semiarid lakes. Results from a laboratory experiment suggest that the addition of a phosphorus sorbent clay associated with an aluminium based coagulant is an effective technique in removing soluble reactive phosphorus and reducing C. raciborskii growth rate – cyanobacteria potentially toxic dominant in reservoirs of Brazilian semiarid – but this effect is dependent on the biomass in the application moment. Results from a field experiment in mesocosm in a eutrophied lake showed that the addition of aluminium based coagulant and removal of benthivorous fish is more efficient in removing total phosphorus and chlorophyll-a from water column than the isolated application of one of the techniques. Lastly, laboratory tests showed that aluminium based coagulant exhibited good performance in removing turbidity and total phosphorus from water of six reservoirs but the efficiency was reduced by algal biomass and pH. The results of this study showed that the improvement in water quality of eutrophied reservoirs in semiarid region is possible through internal loading control by phosphorus precipitation and inactivation in sediments or inhibition of phosphorus release by benthivorous fishes, and also that these results show are additives in water quality improvement.
Resumo:
Eutrophication is the most common cause of water quality degradation in the world. This process occurs by excessive nutrients inputs, nitrogen and phosphorus, to the aquatic systems resulting in algal and cyanobacterial blooms. In shallow lakes these effects are pronounced due to the higher interaction of the lake with watershed, air and sediment. There are innumerous restoration techniques of eutrophied lakes with a range of successful results but there is only one case of successful lake restoration in Brazil: Paranoá Lake in Brasília city. The Brazilian semiarid region has many artificial lakes, named açudes, which are mostly eutrophic and shallow lakes. The eutrophication in these lakes is reported and the phytoplankton community is dominated by potentially toxic cyanobacteria species, mainly Cylindrospermopsis raciborskii. The aim of this thesis is to test techniques for water quality management which can be easily applied in Brazilian semiarid lakes. Results from a laboratory experiment suggest that the addition of a phosphorus sorbent clay associated with an aluminium based coagulant is an effective technique in removing soluble reactive phosphorus and reducing C. raciborskii growth rate – cyanobacteria potentially toxic dominant in reservoirs of Brazilian semiarid – but this effect is dependent on the biomass in the application moment. Results from a field experiment in mesocosm in a eutrophied lake showed that the addition of aluminium based coagulant and removal of benthivorous fish is more efficient in removing total phosphorus and chlorophyll-a from water column than the isolated application of one of the techniques. Lastly, laboratory tests showed that aluminium based coagulant exhibited good performance in removing turbidity and total phosphorus from water of six reservoirs but the efficiency was reduced by algal biomass and pH. The results of this study showed that the improvement in water quality of eutrophied reservoirs in semiarid region is possible through internal loading control by phosphorus precipitation and inactivation in sediments or inhibition of phosphorus release by benthivorous fishes, and also that these results show are additives in water quality improvement.
Resumo:
O presente relatório foi elaborado no âmbito do Mestrado em Educação Pré-Escolar e Ensino do 1.º Ciclo do Ensino Básico, estando organizado em duas partes. Na primeira parte, a dimensão reflexiva, apresenta-se o percurso que realizei ao longo das práticas pedagógicas nos diferentes contextos por que passei, evidenciando as aprendizagens realizadas, as experiências mais significativas, as dificuldades e os desafios que surgiram. Na segunda parte, a dimensão investigativa, é apresentada a investigação realizada numa turma de 1.º ano de escolaridade, que incide na análise de estratégias de cálculo mental utilizadas pelos alunos num contexto de jogo associando a Matemática e a Expressão e Educação Físico-Motora. Este estudo apresenta um carácter qualitativo, uma vez que pretende descrever e analisar as estratégias de cálculo mental utilizadas pelos alunos na realização de jogos motores. Os dados recolhidos revelam que a estratégia mais utilizada foi a estratégia de saltos de x em x e que o facto de as tarefas terem sido implementadas através do jogo facilitou as aprendizagens e permitiu um maior envolvimento e motivação por parte dos alunos.
Resumo:
No futebol a impulsao tem impacto no cabeceio, nos movimentos de antecipaçoes, nos diferentes saltos e de forma geral, na velocidade das açoes de jogo. No entanto, ao contrário de outros esportes como Basquete, Vôlei, Handebol, o seu treinamento específico é pouco visado no futebol. O objetivo deste estudo é verificar, em atletas profissionais de futebol de campo, o perfil da impulsao horizontal e o desenvolvimento dessa durante uma temporada de treinamento e jogos pela segunda divisao do campeonato gaúcho. Foram avaliados 18 atletas de futebol (com média de idade 25±5,44 anos, altura 177,5±6,48 cm e massa corporal 79,4±9,67 kg). Os atletas se submeteram a testes de impulsao horizontal no início (pré) e após três meses de treinamentos (pós). Mediu-se os saltos com ambas às pernas, cinco saltos consecutivos com membro direito (MID) e esquerdo (MIE) e cinco saltos alternados. O perfil de impulsao obtido no pré-teste foi respectivamente 2,22±0,14m, 11,46±0,56 m, 11,69±0,73m e 12,04±0,78m. Os resultados do pós-teste nao se alteraram em comparaçao ao primeiro teste, sendo respectivamente 2,22±0,15m, 11,26±1,12m, 11,46±0,95m e 12,02±0,76m. Conclui-se que o treinamento nao foi capaz de proporcionar desenvolvimento desta capacidade, pois predominantemente as rotinas de treinamento de futebol nao enfocam este desenvolvimento
Resumo:
No futebol a impulsao tem impacto no cabeceio, nos movimentos de antecipaçoes, nos diferentes saltos e de forma geral, na velocidade das açoes de jogo. No entanto, ao contrário de outros esportes como Basquete, Vôlei, Handebol, o seu treinamento específico é pouco visado no futebol. O objetivo deste estudo é verificar, em atletas profissionais de futebol de campo, o perfil da impulsao horizontal e o desenvolvimento dessa durante uma temporada de treinamento e jogos pela segunda divisao do campeonato gaúcho. Foram avaliados 18 atletas de futebol (com média de idade 25±5,44 anos, altura 177,5±6,48 cm e massa corporal 79,4±9,67 kg). Os atletas se submeteram a testes de impulsao horizontal no início (pré) e após três meses de treinamentos (pós). Mediu-se os saltos com ambas às pernas, cinco saltos consecutivos com membro direito (MID) e esquerdo (MIE) e cinco saltos alternados. O perfil de impulsao obtido no pré-teste foi respectivamente 2,22±0,14m, 11,46±0,56 m, 11,69±0,73m e 12,04±0,78m. Os resultados do pós-teste nao se alteraram em comparaçao ao primeiro teste, sendo respectivamente 2,22±0,15m, 11,26±1,12m, 11,46±0,95m e 12,02±0,76m. Conclui-se que o treinamento nao foi capaz de proporcionar desenvolvimento desta capacidade, pois predominantemente as rotinas de treinamento de futebol nao enfocam este desenvolvimento
Resumo:
No futebol a impulsao tem impacto no cabeceio, nos movimentos de antecipaçoes, nos diferentes saltos e de forma geral, na velocidade das açoes de jogo. No entanto, ao contrário de outros esportes como Basquete, Vôlei, Handebol, o seu treinamento específico é pouco visado no futebol. O objetivo deste estudo é verificar, em atletas profissionais de futebol de campo, o perfil da impulsao horizontal e o desenvolvimento dessa durante uma temporada de treinamento e jogos pela segunda divisao do campeonato gaúcho. Foram avaliados 18 atletas de futebol (com média de idade 25±5,44 anos, altura 177,5±6,48 cm e massa corporal 79,4±9,67 kg). Os atletas se submeteram a testes de impulsao horizontal no início (pré) e após três meses de treinamentos (pós). Mediu-se os saltos com ambas às pernas, cinco saltos consecutivos com membro direito (MID) e esquerdo (MIE) e cinco saltos alternados. O perfil de impulsao obtido no pré-teste foi respectivamente 2,22±0,14m, 11,46±0,56 m, 11,69±0,73m e 12,04±0,78m. Os resultados do pós-teste nao se alteraram em comparaçao ao primeiro teste, sendo respectivamente 2,22±0,15m, 11,26±1,12m, 11,46±0,95m e 12,02±0,76m. Conclui-se que o treinamento nao foi capaz de proporcionar desenvolvimento desta capacidade, pois predominantemente as rotinas de treinamento de futebol nao enfocam este desenvolvimento
Resumo:
Perturbation of natural ecosystems, namely by increasing freshwater use and its degradative use, as well as topsoil erosion by water of land-use production systems, have been emerging as topics of high environmental concern. Freshwater use has become a focus of attention in the last few years for all stakeholders involved in the production of goods, mainly agro-industrial and forest-based products, which are freshwater-intensive consumers, requiring large inputs of green and blue water. This thesis presents a global review on the available Water Footprint Assessment and Life Cycle Assessment (LCA)-based methods for measuring and assessing the environmental relevance of freshwater resources use, based on a life cycle perspective. Using some of the available midpoint LCA-based methods, the freshwater use-related impacts of a Portuguese wine (white ‘vinho verde’) were assessed. However, the relevance of environmental green water has been neglected because of the absence of a comprehensive impact assessment method associated with green water flows. To overcome this constraint, this thesis helps to improve and enhance the LCA-based methods by providing a midpoint and spatially explicit Life Cycle Impact Assessment (LCIA) method for assessing impacts on terrestrial green water flow and addressing reductions in surface blue water production caused by reductions in surface runoff due to land-use production systems. The applicability of the proposed method is illustrated by a case study on Eucalyptus globulus conducted in Portugal, as the growth of short rotation forestry is largely dependent on local precipitation. Topsoil erosion by water has been characterised as one of the most upsetting problems for rivers. Because of this, this thesis also focuses on the ecosystem impacts caused by suspended solids (SS) from topsoil erosion that reach freshwater systems. A framework to conduct a spatially distributed SS delivery to freshwater streams and a fate and effect LCIA method to derive site-specific characterisation factors (CFs) for endpoint damage on aquatic ecosystem diversity, namely on algae, macrophyte, and macroinvertebrates organisms, were developed. The applicability of this framework, combined with the derived site-specific CFs, is shown by conducting a case study on E. globulus stands located in Portugal as an example of a land use based system. A spatially explicit LCA assessment was shown to be necessary, since the impacts associated with both green water flows and SS vary greatly as a function of spatial location.
Resumo:
Cada río erosiona hacia abajo en su cauce superior,mientras en su cauce inferior tiene lugar la acumulación de los materiales transportados en su propio lecho. El transporte del material es una función de la velocidad que tiene las aguas del río.Cada río trata de establecer un desnivel continuo desde su nacimiento hasta la base de erosión nivelando saltos y otras interrupciones bruscas de su lecho el límite de su cauce inferior es decir zona de acumulación y cause superior es decir zona de erosión,camina durante este proceso hacia arriba.Dicho límite,en el río San José, se encuentra actualmente a unos 2,5 Km río arriba de Metapán.Desde aquí hasta la embocadura,el lecho del río se levanta continuamente por la acumulación de los sedimentos. Si se pudiera bajar el nivel de la laguna de Metapán el río San José estaría forzado a ajustar el desnivel de su lecho conforme al nuevo nivel del lago,es decir el río erosionaría de nuevo una parte de los sedimentos depositados por el mismo bajando su lecho hasta encontrar su nuevo equilibrio.
Resumo:
Recent paradigms in wireless communication architectures describe environments where nodes present a highly dynamic behavior (e.g., User Centric Networks). In such environments, routing is still performed based on the regular packet-switched behavior of store-and-forward. Albeit sufficient to compute at least an adequate path between a source and a destination, such routing behavior cannot adequately sustain the highly nomadic lifestyle that Internet users are today experiencing. This thesis aims to analyse the impact of the nodes’ mobility on routing scenarios. It also aims at the development of forwarding concepts that help in message forwarding across graphs where nodes exhibit human mobility patterns, as is the case of most of the user-centric wireless networks today. The first part of the work involved the analysis of the mobility impact on routing, and we found that node mobility significance can affect routing performance, and it depends on the link length, distance, and mobility patterns of nodes. The study of current mobility parameters showed that they capture mobility partially. The routing protocol robustness to node mobility depends on the routing metric sensitivity to node mobility. As such, mobility-aware routing metrics were devised to increase routing robustness to node mobility. Two categories of routing metrics proposed are the time-based and spatial correlation-based. For the validation of the metrics, several mobility models were used, which include the ones that mimic human mobility patterns. The metrics were implemented using the Network Simulator tool using two widely used multi-hop routing protocols of Optimized Link State Routing (OLSR) and Ad hoc On Demand Distance Vector (AODV). Using the proposed metrics, we reduced the path re-computation frequency compared to the benchmark metric. This means that more stable nodes were used to route data. The time-based routing metrics generally performed well across the different node mobility scenarios used. We also noted a variation on the performance of the metrics, including the benchmark metric, under different mobility models, due to the differences in the node mobility governing rules of the models.
Resumo:
Relatório Final de Estágio apresentado à Escola Superior de Dança, com vista à obtenção do grau de Mestre em Ensino de Dança.