Papers by Gilson Carvalho
Baía de todos os santos: aspectos oceanográficos
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Environmental Research, 2007
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BioEnergy Research, 2014
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Ecotoxicology and Environmental Safety, 2011
Camamu Bay, an Environmentally Protected Area, may be affected by the pressures of tourism and oi... more Camamu Bay, an Environmentally Protected Area, may be affected by the pressures of tourism and oil exploration in the adjacent continental platform. The current quality of the mangrove sediments was evaluated by porewater bioassays using embryos of Crassostrea rhizophorae and by an analysis of benthic macrofauna and its relationships with organic compounds, trace metals and bioavailability. Porewater toxicity varied from low to moderate in the majority of the samples, and polychaetes dominated the benthos. The Grande Island sampling station (Station 1) presented more sandy sediments, differentiated macrobenthic assemblages and the highest metal concentrations in relation to other stations and guideline values, and it was the only station that indicated a possible bioavailability of metals. The origin of the metals (mainly barium) is most likely associated with the barite ore deposits located in the Grande and Pequena islands. These results may be useful for future assessment of the impact of oil exploration in the coastal region.
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Veterinary Parasitology, 2014
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Marine Environmental Research, 2012
South American estuaries are frequently not included in the search for general ecological models ... more South American estuaries are frequently not included in the search for general ecological models and studies dealing with biological assemblages in estuaries frequently do not sample the entire salinity gradient. We sampled three tropical estuaries, two times each, on ten stations distributed along each system. Six replicates were collected in each station for the benthic macroinfauna and sediment samples for grain size and inorganic contaminant analyses. There were finer sediments at the lower than at the upper estuarine portions. There was a decrease in the diversity, at family level, from marine to freshwater and the differences on the structure of the benthic assemblages were mostly spatial. In spite of the many different characteristics of the three estuaries (e.g. catchment size, pollution levels, proximity with the inner continental shelf) several consistent patterns of benthic macrofauna distribution along these systems were still observed. It suggested a general empirical model regarding the distribution of different benthic invertebrates along tropical salinity gradients which can be tested in different estuaries around the world.
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Scientometrics, 2015
The benthic community ecology of marine and coastal habitats has recently been faced with the cha... more The benthic community ecology of marine and coastal habitats has recently been faced with the challenge of needing a predictive model to anticipate the responses of these natural communities to environmental impacts. This challenge forces the use of quantitative methods to conduct more predictive science. This work is focused on multi-variate quantitative methods applied to community ecological problems. A survey was conducted in the Science Citation Index using combined keywords that reflects multi-variate quantitative methods, benthic assemblages and marine and coastal habitats. There has been analytical inertia in this research field, as the most commonly used methods have not changed over the years, and novel methods that have been developed inside and outside of ecology have not been included in the analytical tools of marine benthic ecologists. Methods that are increasing the predictive power of freshwater benthic ecology, such as machine learning, have not been used for the benthic community ecology of marine and coastal habitats.
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Marine Pollution Bulletin, 2015
Surface sediments collected in the intertidal zone of Paraguaçu estuary in July, 2013, were analy... more Surface sediments collected in the intertidal zone of Paraguaçu estuary in July, 2013, were analyzed for organic matter, nitrogen, phosphorus, grain size fractions and partial concentrations of 16 metals. The USEPA 3051A method and ICP-OES and CV-AAS techniques were chosen to metal analysis. Pollution indices (EF, Igeo and PIN) and a comparison with sediment quality guidelines (UET, ERL, ERM, TEL and PEL of NOAA) were conducted in order to evaluate the potential metal impacts over the area. Principal Component Analysis (PCA) and Pearson correlation results showed the importance of organic matter content and the fine-grained fraction of sediments on the control of the bioavailable metals distribution. The Paraguaçu estuary already has anthropogenic enrichment relative to the background level, especially for Mn, whose values exceeded almost 30 times the background at one site (Mn: 1197.30mgkg(-1)). However, metal levels are still below the reference values with the exception of Hg at one site (Hg: 0.25mgkg(-1), exceeded TEL and ERL).
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Applied biochemistry and biotechnology, Jan 15, 2015
Three lipid extraction methods of hexane Soxhlet (Sox-Hex), Halim (HIP), and Bligh and Dyer (BD) ... more Three lipid extraction methods of hexane Soxhlet (Sox-Hex), Halim (HIP), and Bligh and Dyer (BD) were applied on freeze-dried (FD) and oven-dried (OD) Chlorella vulgaris biomass to evaluate their effects on lipid yield, fatty acid profile, and algal biodiesel quality. Among these three methods, HIP was the preferred one for C. vulgaris lipid recovery considering both extraction efficiency and solvent toxicity. It had the highest lipid yields of 20.0 and 22.0 % on FD and OD biomass, respectively, with corresponding neutral lipid yields of 14.8 and 12.7 %. The lipid profiling analysis showed that palmitic, oleic, linoleic, and α-linolenic acids were the major fatty acids in the algal lipids, and there were no significant differences on the amount of these acids between different drying and extraction methods. Correlative models applied to the fatty acid profiles concluded that high contents of palmitic and oleic acids in algal lipids contributed to balancing the ratio of saturated and...
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Phyllomedusa: Journal of Herpetology, 2014
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Cadernos de Prospecção, 2012
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Sociobiology, 2014
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BioEnergy Research, 2012
ABSTRACT The viability of algae-based biodiesel industry depends on the selection of adequate str... more ABSTRACT The viability of algae-based biodiesel industry depends on the selection of adequate strains in regard to profitable yields and oil quality. This work aimed to bioprospecting and screening 12 microalgae strains by applying, as selective criteria, the volumetric lipid productivity and the fatty acid profiles, used for estimating the biodiesel fuel properties. Volumetric lipid productivity varied among strains from 22.61 to 204.91 mg l −1 day −1 . The highest lipid yields were observed for Chlorella (204.91 mg l −1 day 1) and Botryococcus strains (112.43 and 98.00 mg l −1 day −1 for Botryococcus braunii and Botryococcus terribilis, respectively). Cluster and principal components analysis analysis applied to fatty acid methyl esters (FAME) profiles discriminated three different microalgae groups according to their potential for biodiesel production. Kirchneriella lunaris, Ankistrodesmus fusiformis, Chlamydocapsa bacillus, and Ankistrodesmus falcatus showed the highest levels of polyunsaturated FAME, which incurs in the production of biodiesels with the lowest (42.47–50.52) cetane number (CN), the highest (101.33– 136.97) iodine values (IV), and the lowest oxidation stability. The higher levels of saturated FAME in the oils of Chlamydo-monas sp. and Scenedesmus obliquus indicated them as source of biodiesel with higher oxidation stability, higher CN (63.63– 64.94), and lower IV (27.34–35.28). The third group, except for the Trebouxyophyceae strains that appeared in isolation, are composed by microalgae that generate biodiesel of intermediate values for CN, IV, and oxidation stability, related to their levels of saturated and monosaturated lipids. Thus, in this research, FAME profiling suggested that the best approach for generating a microalgae-biodiesel of top quality is by mixing the oils of distinct cell cultures.
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Marine Pollution Bulletin, 2010
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Ecotoxicology and Environmental Safety, 2011
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seb-ecologia.org.br
Anais do VIII Congresso de Ecologia do Brasil, 23 a 28 de Setembro de 2007, Caxambu - MG ... DIAG... more Anais do VIII Congresso de Ecologia do Brasil, 23 a 28 de Setembro de 2007, Caxambu - MG ... DIAGNÓSTICO AMBIENTAL DO MANGUEZAL DE PORTO DE ... Alessandra Argolo do Espírito Santo1; Aline Amâncio Ramos2; Gilson Correia de Carvalho 3;
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Aquatic Ecosystem Health & Management, 2000
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Papers by Gilson Carvalho