29 resultados para 270702 Marine and Estuarine Ecology (incl. Marine Ichthyology)

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Few studies have been performed with parasites of marine and estuarine fish in southern Brazil. In the present study, unpublished results show the ways of parasitism of juvenile mullet by parasites. The toxicity of formaldehyde and the effectiveness of this chemotherapy in controlling parasites in reared juvenile mullet Mugil liza were also studied. Juvenile mullets (1 +/- 0.26 g; 4.1 +/- 0.4 cm) were exposed to different concentrations of 37% formaldehyde: control group and five formaldehyde concentrations which were tested: T1 (13.5), T2 (21.6), T3 (40.5), T4 (81) and T5 (135) mg L-1 with 8 fish per repetition in triplicate. To verify the drug effectiveness in parasitic control, juvenile mullets were exposed to 1 h prophylactic bath of 37% formaldehyde with a control group and five formaldehyde concentrations: T1 (67.5), T2 (135), T3 (270), T4 (405) and T5 (540) mg L-1, 8 fish per repetition in triplicate. Ligophorus cf. uruguayensis (Monogenoidea: Ancyrocephalidae) and Solostamenides cf. platyorchis (Monogenoidea: Microcotylidae) were identified in the gills. Digenea and Nematoda were observed in the intestines. This is the first occurrence of S. cf. platyorchis in Brazil. During the toxicity test, the LC50-96 h was estimated at 20.77 mg L-1 of formaldehyde. During the 1 h formaldehyde prophylactic bath, all parasites were eliminated in formaldehyde concentrations between 135 and 540 mg L-1. High survival rate was observed in all treatments. Values of prevalence and intensity of infestation observed in this study showed the potential damage caused by Monogenoidea to mullet. Formaldehyde baths with 135 mg L-1 are recommended to control Monogenoidea in mullet and the safe limits for formaldehyde use were presented. Besides, the endoparasites were tolerant to formaldehyde exposure. (C) 2012 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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This study presents an environmental oil spill sensitivity map of Cardoso Island State Park, located in São Paulo state, Brazil, including some of its surrounding areas. This map was designed following the procedures determined by the Brazilian Federal Environment Organ (Ministry of the Environment), which separates coastal habitats in different littoral sensitivity indexes (LSI) to oil spills. We have also analysed some seasonal variations in morphologic and textural parameters at the local marine beaches that could affect their sensitivity, having found that they are more sensitive during summer due to a wider foreshore zone during these periods. Local most sensitive habitats are estuarine mangroves (LSI 10) and estuarine mud banks (LSI 9). Marine beaches were ranked LSI 3, and littoral rocky shores were subdivided in exposed flat rocky shores (LSI 1), boulder rocky shores (LSI 6) and sheltered rocky shores (LSI 8). Due to the elevated sensitivity of an estuarine system in the area, we considered necessary the installation of an Environmental Emergency Centre and the design of an emergency plan for the region in case of an accident resulting in oil spills within its vicinities. (C) 2007 Elsevier Ltd. All rights reserved.

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The objective of this work is to analyze the effects of salinity and wastewater on the zooplankton community of the Itanhaém river estuary, São Paulo state. Samples of zooplankton as well as physical and chemical variables of water were collected in four sites, located between the coastal line and the superior part of the estuary, including a secondary channel where wastewater is thrown without previous treatment. The samples were collected in low and high tide in winter and summer. Results showed that the estuary presents a temporal and spatial variation of physical and chemical characteristics, especially salinity, in function of the tide and seasonal variation of rain. The high values of salinity occurred in winter and high tide. Zooplankton community was adapted to the dynamic of salinity, and marine and estuarine species occurred in the low part of the estuary in winter. Although the Itanhaém river estuary has the same temporal and spatial dynamic of other estuaries, the values of salinity are low when compared with others located in the southern coast of São Paulo. Consequently, mainly oligohaline and fresh water species constitute the zooplankton community. These characteristics are due to the great drainage area of the Itanhaém river basin. The waste water modified physical and chemical characteristics of water that now presents higher concentrations of nutrients, higher values of suspended matter and lower concentrations of oxygen. It was observed a positive relation between the density of nauplii of copepods and organic pollution in this estuary.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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

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There has been much discussion on the importance of Brazilian ethanol in promoting a more sustainable society. However, there is a lack of analysis of whether sugarcane plants/factories that produce this ethanol are environmentally suitable. Thus, the objective of this study was to analyse stages of environmental management at four Brazilian ethanol-producing plants, examining the management practices adopted and the factors behind this adoption. The results indicate that (1) only one of the four plants is in the environmentally proactive stage; (2) all plants are adopting operational and organisational environmental management practices; (3) all plants have problems in communicating environmental management practices; and (4) the plant with the most advanced environmental management makes intense use of communication practices and is strongly oriented towards a more environmentally aware international market. This paper is an attempt to explain the complex relationship between the evolution of environmental management, environmental practices and motivation using a framework. The implications for society, plant directors and scholars are described, as well as the study's limitations.

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

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Aim: Studies on feeding of early life stages are very important to the understanding of the biology and trophic ecology of fish species. Therefore, the aim of this work is to describe the development of the digestive tube, and to characterize the diet of larvae and juveniles of Bryconamericus stramineus Eigenmann, 1908 of the upper Parana River floodplain; Methods: Larvae were obtained from, monthly samples during nychthemeral cycles with four-hour interval between samplings from February/91 to February/92, utilizing a conical-cylindrical plankton net; Results: At the preflexion stage, larvae at approximately 4.00 mm SL, showed a morphologically undifferentiated straight tube, with the anterior region more dilated. At the flexion stage a differentiation in the anterior region of the digestive tube occurs, with the intestine wall getting thicker (8.30 mm SL). The formation of pyloric caeca occurs at 9.00 mm SL. At the postflexion stage the first loop is formed at 9.25 mm SL and the second loop at about 10.00 mm SL. Bryconamericus stramineus consumed mainly cladocerans, also ingesting copepods, rotifers, nematodes, algae, insects and inorganic particles. Along the development, there was an increase in the number of food items and a diversification in the number of consumed taxa; Conclusions: Changes in the diet of B. stramineus larvae were not observed, being them zooplanktivores during all the initial development. However, an increase of large preys, such as insects larvae, was observed at the end of the larval period and in juveniles, suggesting a tendency towards invertivory. Larvae and juveniles preferentially fed during the night.

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Fuel cells are electrochemical energy conversion devices that convert fuel and oxidant electrochemically into electrical energy, water and heat. Compared to traditional electricity generation technologies that use combustion processes to convert fuel into heat, and then into mechanical energy, fuel cells convert the hydrogen and oxygen chemical energy into electrical energy, without intermediate conversion processes, and with higher efficiency. In order to make the fuel cells an achievable and useful technology, it is firstly necessary to develop an economic and efficient way for hydrogen production. Molecular hydrogen is always found combined with other chemical compounds in nature, so it must be isolated. In this paper, the technical, economical and ecological aspects of hydrogen production by biogas steam reforming are presented. The economic feasibility calculation was performed to evaluate how interesting the process is by analyzing the investment, operation and maintenance costs of the biogas steam reformer and the hydrogen production cost achieved the value of 0.27 US$/kWh with a payback period of 8 years. An ecological efficiency of 94.95%, which is a good ecological value, was obtained. The results obtained by these analyses showed that this type of hydrogen production is an environmentally attractive route. © 2013 Elsevier Ltd.