149 resultados para Aquatic pollution
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Electrochemical experiments in acetic acid-acetate buffer (pH 4.5) are conducted in order to understand metallic and ionic mercury adsorption processes on the pyrite surface. The nature as well as the extent of the spontaneous interaction between pyrite and mercuric ions was evaluated. The spontaneous reduction of mercury species onto pyrite surface was confirmed. These results represent a first step for the use of mining wastes rich in pyrite for mercury pollution abatement. (c) 2005 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Human development and population growth during the twentieth century increased the water demand, tripling its consumption between 1950 and 1990. As the water streams were polluted; and as water is the source of minerals and also regulates vital functions, it becomes the vehicle of transmission and consequently spreads many diseases. Probably, the industries are the major responsible for this pollution when they dump untreated effluents to water streams, saturating the already insufficient net of sanitation facilities polluting water and soil. An effective treatment has been established with low cost in Europe and the United States, through constructed systems on wetlands Constructed Wetland Systems - CWSs, gradually used in other countries in the last three decades. Lately, we observe a continuous growth in Brazilian poultry business, and poultry industry showed greatest dynamism in the country, following the global market. Pondering this information and the efficiency of such treatment, this work aimed to study prototypes, in a laboratory scale, simulating ascending and descending types of CWSs, vegetated with aquatic macrophytes Eichhornia crassipes and the uses of aggregates and soil, to treat industrial wastewater from slaughterhouses and aviary. We conducted the initial characterization of the effluent to have an idea of its constituents and to scale the system and the continuous flow. Furthermore, we characterized the soil to be used in this system. The collects are periodically made in the refrigeration industry FRICOCK FRIGORIFICAÇÃO AVICULTURA INDÚSTRIA E COMÉRCIO LTDA. for local treatment simulation. The effluent that was treated with 12 prototypes of CWSs are analyzed with some frequency. The results of these reviews were compared to the effluent coming from the industry... (Complete abstract click electronic access below)
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As an effect of the imbalance caused by the damming of rivers and pollution, it has been observed a growing aquatic plants infestation in reservoirs for the generation of electricity. In addition to power generation, these sites have also been used for various other purposes, including recreation, attracting water and navigation. Thus it is important to evaluate these water bodies periodically, in order to verify the leading conditions to the growth of algae, plants and other organisms. In this sense, Remote sensing technology can be a valuable tool for mapping and monitoring the occupation of land in the vicinity of the water body and the optical properties of water, to provide subsidies for the effective management of these aquatic environments. This paper aims to perform the monitoring of the occurrence of aquatic plants in Salto Grande Hydropower Reservoir, located in Americana (SP) and, periodically, map the occupation of land in the vicinity of the water body, through multispectral images taken by sensors on the satellites Landsat series in seven consecutive years: 2004, 2005, 2006, 2007, 2008, 2009 and 2010. The adopted methodological procedure included the images data and the classification of multispectral images to map, every year, the location and extension of the area infested by aquatic plants and the occupation of land
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Water is an essential factor in maintaining the vital functions of living beings. We have observed a growing commitment of quality, are due to pollution from many sources and even entire watersheds, whether for industrial waste, sewage, or for substances used in farming such as pesticides, herbicides and fertilizers. Nickel is the 24th most abundant element on earth, is a heavy metal that, in the form of chloride, is a proven genotoxic and mutagenic. Due to its industrial use, there was considerable increase of its concentration in surface sediments. Fish combine characteristics that make them excellent experimental models for aquatic toxicology studies, which are particularly usable as warn about the potential danger of chemicals or the possibility of environmental pollution. Due to impaired water quality and the few published studies relating the nickel with the tissue change, this study aimed at assessing the consequences of the presence of nickel in the aquatic environment. For this analysis, we used individuals of Oreochromis niloticus, exposed for 96 hours at three different concentrations of nickel dissolved in water compared to a control group. After exposure, the gills were removed and these were analyzed by ultramorphological, histological and histochemical analysis. The results indicate that all concentrations used in the experiment altered the histophysiology of exposed individuals. We observed the following changes: rupture of paviment cells, thus resulting in bleeding, loss of microridges surface of these cells and epithelial loss in the gills of all animals in all treatments with nickel chloride, the histochemical analysis showed non-proliferation of chloride cells. However, there was a dose-dependent increase of mucus cells in all animals. Therefore, nickel has toxic potential to fish, from the smallest concentration used up to twice as permitted by law, indicating... (Complete abstract click electronic access below)
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Aquatic ecosystems are suffering many impacts caused by human activities resulting from the activities occurring around them. With technological progress observed in recent years, this environment has received large amounts of chemicals from industries, agriculture and urban area that affect the aquatic biota. Among these sources of contamination, the oil industry has contributed to the pollution of aquatic environments with both effluents as produced water well as oil spills and their derivatives having toxicity to various organisms. With all the environmental issues has increased concern about water quality and has been used ecotoxicological tests with aquatic organisms to ecosystems to assess the toxicity of chemicals present in the water. In this context the microcrustacea Daphnia similis stands out as a freshwater organism very representative of the aquatic fauna of rivers and high sensitivity to environmental impacts. Thus, the present study aimed to evaluate the lethal toxicity of crude oil and produced water on this microcrustacea. The results showed that the microcrustacea presented high sensitivity to contaminants primarily crude oil. There was also the influence of environmental variables pH and temperature on the survival of organisms
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)