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Search Results: 1 - 10 of 85120 matches for " José Ant?nio Baptista Neto "
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Análise Multivariada de Dados Ecológicos da Baía de Guanabara- RJ,com Base em Foraminíferos Bent nicos.
Priscila Tavares dos Santos,Claudia Gutterres Vilela,José Antnio Baptista Neto,Antnio Enrique Say?o Sanjinés
Anuário do Instituto de Geociências , 2007,
Abstract: Guanabara bay is an estuary environment situated in the seaboard of Rio de Janeiro state, under the coordinates 22o 40’ and 23o 00’S and 43o 00’ and 43o 20’W. Nowadays, it has an approximate area of 377 km2, it has had a reduction of 91 km2 since the discovery of Brazil, being considered one of the most polluted seacoast regions of the country. The environmental monitoring of Guanabara bay becomes increasingly necessary in order to be capable of taking effectivemeasures in its management. Therefore, the use of bioindicator organisms, like foraminifera, is an excellent tool because of their rapid response to environmental changes. The goal of this paper is to apply statistical analyses to the biotic data benthicforaminifera), aiming to observe how they behave in Guanabara bay. In November 1999, samples of bottom sediment were collected along Guanabara bay; 52 of them distributed along all the bay were used in this study. They were treated and classified according to the pattern methodology for foraminifera. For the numerical ecology, grouping analysis and indicating species analysis (ISA) were done using the programs Statistica 6.0 and PCORD. Through the groupinganalysis, it was observed the formation of groups in both samples and species. ISA showed what species is the best one toindicate the actual state of Guanabara bay - Ammonia tepida. The multivaried ecological analyses had an optimal response in the evaluation of patterns of pollution in Guanabara bay, based on benthic foraminifera.
Distinctive sedimentary processes in Guanabara Bay - SE/Brazil, based on the analysis of echo-character (7.0 kHz)
Catanzaro, Leonardo F;Baptista Neto, José Antnio;Guimar?es, Mauricio Souza Dias;Silva, Cleverson G;
Revista Brasileira de Geofísica , 2004, DOI: 10.1590/S0102-261X2004000100006
Abstract: guanabara bay bottom sediments and seabed characteristics were analysed using high-resolution (7 khz) sub-bottom profiles associated with particle size analyses of 92 bottom sediment samples. eight types of echo-characters were identified revealing the strong relation with the particle size distribution. sandy bottom areas presented strong echo reflections, without sub-bottom penetration (echo types i and iii), while in muddy areas sub-bottom reflections showed the acoustic basement delineating buried sugar-loaf hills and infilled-valley features (echo type iv). the presence of shallow gas within the sediments is indicated by acoustic blanket and a series of bottom-multiple reflections (echo types va and vb). erosion by bottom currents and artificial mechanical dredging are suggested by truncations of sub-bottom reflections and a wrinkled seabed surface (echo types vi and vii). crystalline basement outcrops on the seabed are recognized by multiple or single hyperbolae with varying elevations above the bay bottom (echo type ii).
ESTUDO GEOAMBIENTAL DAS CONCENTRA ES DE HIDROCARBONETOS DE PETRóLEO (POLICíCLICOS AROMáTICOS – HPAs) AO LONGO DO RIO ESTRELA, BAíA DE GUANABARA – RJ
Carlos Marclei Arruda Rangel,José Antnio Baptista Neto,Estefan Monteiro da Fonseca
Revista Tamoios , 2013,
Abstract: RESUMO Neste estudo, análises geoquímicas de dez amostras de sedimentos coletados ao longo do sistema fluvial do Rio Estrela, localizado ao norte da Baía de Guanabara, evidenciam a presen a de impactos antropogênicos nesta área. As concentra es de hidrocarbonetos policíclicos aromáticos (HPAs) obtidas mostraram-se ligeiramente elevadas, quando comparadas com valores encontrados em ambientes naturais. Os HPAs foram analisados nos sedimentos ao longo da bacia do Rio Estrela. Embora as concentra es destes compostos detectados nesta área tenham ocorrido em baixas propor es, os tipos de HPAs detectados com alto peso molecular, s o mutagênicos e carcinogênicos. Por esta raz o, compreender a dinamica de transporte, deposi o e riscos ambientais dos HPAs para o sistema ecológico, especialmente para o sistema aquático, s o importantes formas de monitoramento deste ambiente. Palavras chaves: Rio Estrela, Baía de Guanabara, Polui o, HPAs ABSTRACT In this study, the geochemical analysis of ten sediments samples collected along the fluvial system of the Estrela River, located in the northern portion of Guanabara Bay, shows the presence of anthropogenic impacts in this area. Concentrations of polycyclic aromatic hydrocarbons (PAHs) obtained were slightly higher when compared with values found in natural environments. The PAHs were tested in sediments along the drainage basin of Estrela River. Although the compounds found in this area have occurred in low proportions, PAHs compounds detected, with high molecular weight, are mutagenic and carcinogenic. For these reason, understanding PAHs transport, fate and environmental risk to ecological system, especially for aquatic ecosystem, are important forms of monitor this environment. Keywords: Estrela River, Guanabara Bay, Pollution, PAHs
FONTES E TRANSPORTE DE METAIS PESADOS PARA ENSEADA DE JURUJUBA (BAIA DE GUANABARA) RJ - BRASIL
José Antnio Baptista Neto,Bernard J. Smith,John J. McAllister,Maria Augusta Martins da Silva
Revista Tamoios , 2005,
Abstract: As fontes de sedimentos e metais pesados para um estuário urbanizado s o complexas e difusas. Esta pesquisa tem como objetivo acessar as principais fontes de metais pesados para a enseada de Jurujuba (RJ). Analisaram- se as concentra es dos elementos Cr, Cu, Ni, Pb, Zn e Fe, em amostras de solo, rios e escoamento superficial urbano, bem como sedimentos de marinas. Apesar de se poderem distinguir as fontes naturais das antrópicas de metais pesados para a Enseada de Jurujuba, é evidente que os processos de urbaniza o s o os principais responsáveis pelas maiores concentra es de metais pesados para a enseada, através de rios e escoamento superficial urbano. No entanto, n o se podem desprezar a deposi o atmosférica e as atividades náuticas como importantes fontes de polui o. Palavras-chave: fontes de sedimentos, polui o de metais pesados, Enseada de Jurujuba, processo de urbaniza o.
Avalia o da Polui o Antrópica Usando Padr o de Distribui o deEspécies de Foraminíferos Provenientes de Testemunhos da Baía de Guanabara, RJ.
Brígida Orioli Figueira,Claudia Gutterres Vilela,José Antnio Baptista Neto
Anuário do Instituto de Geociências , 2007,
Abstract: This work presents a study of benthic foraminifera recovered from three cores collected near the Paquetá island, in the Guanabara bay, Rio de Janeiro, southeastern Brazil. The cores have different sizes and were subsampled in centimetric intervals. The recovered benthic foraminiferal assemblages were thoroughly identified, in order to carry out an ecological study towards reconstructing the environmental evolution of the studied area during the recent historical period and assessing the response of the foraminiferal assemblages to the locally occurring natural and/or anthropogenic impacts. The microfaunal distribution results were correlated with the sedimentological and TOC (Total Organic Carbon) data to understand the environmental trends and evaluate the varying patterns of human-related pollution in the area. 14C isotopic date was taken at the bottom of one core, to help for the local sediment accumulation rates. Species diversity values were low in all samples, whereas the TOC values were commonly high, increasing dramatically upwards across the cores.The dominant species in that area of the Guanabara bay were Ammonia tepida, Elphidium spp. and Buliminella elegantissima. Patterns of the distributions of these species confirm the influence of the anthropogenic pollutiontoward the top of the cores.
Pollen Analysis Revealing the Paleoenvironment of a 3520 years B.P. old Sediment in the Guanabara Bay, Rio de Janeiro, Brazil
Ortrud Monika Barth,Cintia Ferreira Barreto,Claudia Gutterres Vilela,José Antnio Baptista-Neto
Anuário do Instituto de Geociências , 2011,
Abstract: O presente trabalho visou indagar a dinamica de diferentes tipos de vegetac o que ocorriam na regi o da Baía de Guanabara, Rio de Janeiro, durante o Holoceno recente, analisando um nível de sedimento com a idade convencional de 3520 + 50 anos A.P., coletado na enseada de Jurujuba. A análise palynologica do sedimento indicou a predominancia da Floresta Ombrófila. Táxons botanicos de vegetac o de Campo n o eram frequentes. As condic es ambientais eram favoráveis ao desenvolvimento de plantas higrófitas. Dinamica similar deste evento transgressivo do nível do mar foi também observado em outras áreas litoraneas do estado do Rio de Janeiro, distantes da Baía de Guanabara.
Distribui??o sedimentar da Lagoa Rodrigo de Freitas através de sísmica de alta resolu??o
Baptista Neto, José Antnio;Silva, Cleverson Guizan;Dias, Gilberto Tavares de Macedo;Fonseca, Estefan Monteiro da;
Revista Brasileira de Geofísica , 2011, DOI: 10.1590/S0102-261X2011000100013
Abstract: the rodrigo de freitas lagoon (rio de janeiro state) sediments and bottom characteristics were analyzed using high-resolution (10 khz) sub-bottom profiles associated with particle size analyses of 44 bottom sediment samples. four types of echo-characters were identified revealing the strong relation with the particle size distribution and bottom morphology. in areas of acoustic penetration, the basement delineates buried sugar-loaf hills and infilled-valley features. the total sediment thickness can reach as much as 16 meters along the paleovalleys, which are aligned in a ne-sw direction, parallel to the regional basement orientation observed on the coastal massifs. there is a predominance of organic rich muddy sediments, infilling the paleovalleys which are the main sites of shallow gas occurrences within the lagoonal sediments.
PRODUTOS DO INTEMPERISMO E AVALIA O DO NíVEL DE DETERIORA O EM ROCHAS ORNAMENTAIS DA FORTALEZA DE SANTA CRUZ (NITERóI, RJ)
André Luiz Carvalho da Silva,Maria Augusta Martins da Silva,José Antnio Baptista Neto,Bernard Smith
Revista Tamoios , 2013,
Abstract: RESUMO A Fortaleza de Santa Cruz, magnífico exemplo da arquitetura dos tempos da chegada dos europeus ao nosso continente, come ou a ser construída por volta de 1555 na entrada da Baía de Guanabara (Niterói, RJ) com blocos de gnaisse facoidal local. De modo geral, rochas empregadas em constru es em ambientes litoraneos e urbanos s o expostas ao sal marinho, bem como, aos poluentes CO2, S e N e, em decorrência disso, os processos relacionados ao intemperismo podem causar danos consideráveis a essas constru es. Na Fortaleza de Santa Cruz foram identificados diversos tipos de crostas (negra, de sal, organica, “flowstones”) e estalactites como produtos do intemperismo. A intensidade dos processos é diferente nos três pavimentos que comp em a Fortaleza, levando a níveis distintos de deteriora o dos blocos de rocha, em fun o da circula o, teor de umidade e de sal no ar em cada pavimento. Palavras-chaves: intemperismo; rochas ornamentais; crosta negra; dissolu o. ABSTRACT The Santa Cruz Fort, a magnificent example of architecture at the time of arrival of the Europeans to our continent, began to be constructed at about 1555 at the entrance of the Guanabara Bay (Niterói, RJ) with local blocks of augen gnaiss. In general, rocks employed in constructions in coastal and urban environments are exposed to sea derived salts and pollutants such as CO2, S and N and, as consequence of that, weathering related processes can cause considerable damage to these constructions. In the Santa Cruz Fort, various types of crusts (black, salt, organic, flowstones) and stalactites have been identified as weathering products. The intensity of such processes is different in the Fort’s three main floors and that leads to distinct deteriorations levels of the blocks of rock in each floor, a function of air circulation, humidity and salt content. Keywords: Weathering; building stones; black crust; dissolution.
Análise dos Foraminíferos Bent nicos de Dois Testemunhos na Regi o Nordeste da Baía de Guanabara.
Raquel Batista Medeiros da Fonseca,Kelly Cristine Costa de Abreu,Claudia Gutterres Vilela,José Antnio Baptista Neto
Anuário do Instituto de Geociências , 2007,
Abstract: Guanabara bay receives a large amount of industrial and domestic sewage, which contributes for its environmental degradation. For monitoring those environmental changes, two cores from the northeastern area of the bay were analized.They were subsampled in centimeter intervals and the laboratory treatment followed specific methodology for foraminifera. Foraminifera are much sensitive microorganisms as to environmental changes as to anthropogenic ones, thus they are useful as pollution indicators. The results show low values of diversity, however, a higher diversity in the core T15,between Paquetá island and S o Gon alo than in the core T14, at S o Gon alo south region. Both of them presented Ammonia tepida as a dominant species human pollution bioindicator, and Buliminella elegatissima as bioindicator of high levels of organic matter.
Bacteriological study of the superficial sediments of Guanabara bay, RJ, Brazil
Sobrinho da Silva, Frederico;Pereira, Daniella da Costa;Nu?ez, Leonisa Sanchez;Krepsk, Natascha;Fontana, Luiz Francisco;Baptista Neto, José Antnio;Crapez, Mirian Araújo Carlos;
Brazilian Journal of Oceanography , 2008, DOI: 10.1590/S1679-87592008000100002
Abstract: thirty sediment samples were collected in guanabara bay in august, november and december 2005. the material was analyzed for organic matter, total and faecal coliforms, heterotrophic bacteria, bacterial respiratory activity, esterase activity and electron transport system activity. the organic matter in the superficial sediments (2 cm) ranged from 4 to 6%. the highest level of total coliforms and faecal coliforms were 1.7 x 105 mpn/g and 1.1 x 103 mpn/g, respectively. heterotrophic bacteria presented the highest values at station 7 (4.1 x 106 cfu/g) and the lowest values at station 3 (7 x 104 cfu/g) (northwestern part of guanabara bay). esterase enzyme activity showed activity in the sediment of all 30 stations. electron transport system activity ranged between 0.047 ml o2/h/g and 0.366 ml o2/h/g at six stations. the benthic microbial foodweb is anaerobic. anaerobic processes such as fermentation, denitrification and sulphate-reduction are responsible for the biogeochemical cycles in the sediment of guanabara bay. the input of untreated sewage in the mangue channel outflow in guanabara bay has favored the increase of the organic load, and the maintenance of the total coliforms and faecal coliforms in the sediment. faecal coliforms have been reported to be a good indicator of aquatic pollution and organic contamination in the water column, but total coliforms may be an ideal candidate group for sediment quality tests as well.
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