Navegando por Assunto "Sedimentos (Geologia)"

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Aplicação da cromatografia líquida de alta eficiência na investigação de hidrocarbonetos policíclicos aromáticos em testemunhos sedimentares
(Universidade Federal do Pará, 2013-07-31) EVANGELISTA, Camila do Carmo Pereira; KAWAKAMI, Silvia Keiko; http://lattes.cnpq.br/5306256489815710
Polycyclic aromatic hydrocarbons are organic (PAH) compounds originated from natural or anthropogenic sources and are considered priority substances by environmental agencies because of carcinogenic and mutagenic potentials. Therefore, rapid and low cost analytical methods for these compounds are of significant relevance for environmental purposes. The present study aimed the optimization of an analytical method for PAHs using High Performance Liquid chromatography with a diode array detector (HPLC-DAD) for the application to an estuarine sediment core. For the optimization and evaluation of the method, a sedimentary column measuring 46 cm length was collected at the mouth of the Igarapé Tucunduba (Belém, Pará) and sectioned in 2 cm portions. After dryness, 30 g of each portion were extracted with a mixture of dichloromethane in acetone in ultrasound bath for 40 min. the extracts obtained were centrifuged, purified on silica gel as a clean-up adaptation mainly to retained fine particles, then concentrated using vacuum evaporator and filtered through 0,2 μm nylon membrane before HPLC injection. Samples spiked with 16 PAH analytical standards and procedural blanks were processed on the same way. The parameters assessed showed: (1) good linearity, the calibration curves presented high correlation coefficients ; (2) adequate accuracy: relative standard deviations within acceptable values with 2,1% for acenaphthylene and maximum of 19,7% for fluoranthene; (3) low detection limits between 0,004 to 1,085 ng g-1 which make in situ determinations feasible; (4) adequate recovery for traces with minimum of 40,0% for acenaphthylene and maximum of 103,1% for benzo(k)fluoranthene. The total PAH concentration in the sediment core ranged between 60,77 to 783,3 ng g-1 dry sediment. The optimized method showed advantages over the traditional methods based on soxhlet extrations and clean up adsorption columns in terms of time of analysis and reduced costs with the use of smaller amounts of solvents. The limitation, however, was de coelution of some compounds, which is probably due to the low efficiency of the chromatographic column that was available at the time of the analysis. The method was applicable to estuarine complex samples, rich in silt and clay. Diagnostic ratios using parental PAHs indicated petrogenic sources at 24 - 26 cm and 28 – 30 cm depth; and pirolitics sources at 6 - 8 cm, 10 - 12 cm , and 14 - 16 cm respectively.
Acesso aberto (Open Access)
Avaliação ambiental dos recursos hídricos, solos e sedimentos na área de abrangência do depósito de resíduos sólidos do Aurá - Belém-PA
(Universidade Federal do Pará, 2002-03-27) PIRATOBA MORALES, Gundisalvo; FENZL, Norbert; http://lattes.cnpq.br/6834981018643186
With 1.754.099 inhabitants, the municipality of Belém produces roughly 1,200 tons per day of all kinds of waste, which are deposited in a landfill known as Lixão do Aurá, bordering the municipality of Ananindeua. During the past 11 years, this area has been accumulating approximately three million and two-hundred thousand tons of solid waste, transforming that place into a permanent local source of anthropogenic pollution, altering environmental conditions and resources around the whole area surrounding it. A Vertical Electrical Resistivity Sounding (VERS) procedure, conducted in the area before it was transformed into the landfill (1991), compared with the measures taken eight years later (1998), show that the land resistance has considerably dropped, with values in some cases — 109 times smaller than the original ones, thus indicating that the layers have been affected by the leach from waste decay. Fifteen profiles were conducted in the area, using the electrical imaging system, allowing us to confirm the (VERS) results, with evidences that the underground water has been affected by the infiltration and by the leachate vertical and horizontal movements. The hydro geological characteristics in the area show that the local predominant type of aquifer is of the free kind, locally confined, with hydraulic gradient of approximately 0.695%, effective porosity of 28%, permeability coefficient ranging from 1.1 x 10-3 to 0.9 x 10-4 cm/s, and underground flows running north/south towards the Guamá River, at approximately 14.79 m/year. A multivariate statistical analysis has shown that superficial water samples, collected simultaneously at three control points, during one tide cycle, regardless of the season, portray totaily different behaviors, indicating that superficial water resources are being affected by the superficial movement of leachate. With the concentration value figures for each of the leachate parameters (pH, conductivity, alkalinity, ammonia, total organic carbon, chloride, sodium, potassium, calcium, and magnesia), plus the flow of the Aurá River at the control point near the Guamá River, it is possible to estimate the quantity of pollutants that the solid waste landfill sends into the water system. During one tide cycle, in the dry season, the solid waste landfill deposits approximately 13,115 kg of chloride, 417 kg of ammonia, and 129,767 kg of salts in the local water system. For the underground waters, the multivariate statistics showed that the samples collected In the monitoring wells in the area show significant differences, indicating that the wells located downstream have been affected by the leachate. The presence of sand layers right in the area where solid waste is deposited allows for the vertical and horizontal movement of the different pollutants originated by the leachate. The heavy metais anaiyses, conducted under the sequential extraction methodology, showed percentages in the geochemical phases potentially bio-available in the studied soil and sediment samples. In the soil samples, the potentially bio-available fraction (replace, reduce, and organic geochemistry phases) contained an average of 32% of the total Cadmium (Cd), 11.8% of the total Chromium (Cr), 23% of the total Copper (Cu), 12.32% of the total Nickel (Ni), 43.1% of the total Lead (Pb), and 31.01% of the total Zinc. The potentially bio-available phases percentage in the sediments of the area was greater than the ones found in the soil samples. In these sediments, the quantity of heavy metais in the potentially bio-available fraction, shown higher values during the dry season than during the rainy season; for instance, 33% of the total Cd measured during the rainy season increased to 37% in the dry season; Pb increased from 61 to 70%; Zn, from 51 to 54%, among others. The metais analyzed by total attack in the soil samples, compared with the sandstone backgrounds, indicate that the Fe (3.1%), Cu (18.5 ppm), Ni (10.1 ppm), Pb (69.5 ppm), Cr (76 ppm), and Cd (>1 ppm) are above normal standards. In the case of sediment samples, the EPA background values (total concentration) would be moderately polluted by Cr (average 64.6 ppm) and heavily polluted by Fe (3.8%) and Mn (600 ppm). These results show that the sediments were not polluted by Pb and Zn. Considering the potentially bio-available phase and using the tool provided by a Geographic Information System (GIS), we can say that, during the rainy season, the sediment samples were not polluted by Cr (potentially bio-available fraction smaller than 20% of the total) were highly polluted by Pb and Zn (PBD higher than 50%), and moderately polluted by Cu, Ni, and Cd (PBD between 20 and 50%).
Acesso aberto (Open Access)
Avaliação da qualidade ambiental da baía do Guajará em Belém - PA
(Universidade Federal do Pará, 2018-03-29) SANTOS, Letícia Furtado dos; SOUSA, Adriano Marlisom Leão de; http://lattes.cnpq.br/4371199443425884
Water is a fundamental natural resource for the maintenance of life, so it is of the utmost importance to preserve its quality. However, with the increase of anthropic activities, it has been under severe pressure, something that can affect its quality. Thus, it is necessary to monitor the water bodies, evaluating the physical, chemical and biological factors, in order to know if such activities are causing risks to the quality of this natural resource. The objective of this work was to evaluate the environmental quality of Guajará Bay, through the analysis of water quality, sediment and benthic macroinvertebrates. The collections occur in the year 2015 and 2016, in distinct seasonal periods, rainy and less rainy, characteristic of the Amazon region. The study was performed in 4 points (PT01, PT02, PT03 and PT04). In the water analysis, the physical-chemical and microbiological parameters were evaluated; in the study of the sediment (total and leachate) was quantified the Cr, Cd, Cu and Fe metals, calculating the FC (Contamination Factor), IGeo (Geoacumulation Index) and FE (Enrichment Factor); and in the analysis of the benthic macroinvertebrates the ecological descriptors and the FAB (Bioaccumulation Factor) were evaluated. In the precipitation analysis, the precipitated volume was above the average of the normal climatological in the rainy period, and in the less rainy period it was below the average. In the chemical and microbiological analyzes of the water, the OD (dissolved oxygen) parameter was below that allowed by CONAMA Resolution nº357/05, BOD (biochemical oxygen demand) and thermotolerant coliforms above the reference limit, in addition to high concentrations of COD (chemical oxygen demand) and high CE (electrical conductivity). In the evaluation of the sediment the total sediment Cd presented values above that allowed by PEL and CONAMA nº 454/12, already in the leached phase, all the metals were within the allowed by the legislation. In general, the points presented low to moderate contamination, characterized as an unpolluted environment to a moderately polluted and enriched deficiency. In the analysis of the benthic macroinvertebrates, the most representative phylum found was the Annelida, with most of the species referring to the class Polychaeta and the subclass Oligochaeta (class Clitellata). The Oligochaetas belonging to the Tubificidae family was the most prominent. Such family is characterized as tolerant and opportunistic to situations of hypoxia, being able to inhabit in environments with eutrofizada water. The results of the ecological descriptors showed that the greatest richness, abundance, diversity and better equitability were found in the less rainy period, due to the higher concentration of nutrients and organic matter caused in this period, benthic individuals presented bioaccumulation at all points for metals Cd, Cr, Cu. The results of the matrices analyzed in the study indicated that the accumulation of pollutants in Guajará bay is due to anthropic activities, mainly by the disposal of domestic sewage without pre-treatment that is launched in this region and port activity. Thus, the importance of continuous monitoring is emphasized, given that such contamination, besides causing damages to the aquatic ecosystem, causes harm to the population, since it uses this water body for practices and recreation and fishing.
Acesso aberto (Open Access)
Avaliação geoquímica da ocorrência de metais pesados selecionados em sedimentais pelíticos da plataforma continental do Amazonas no trecho entre a foz do rio Pará e o cabo Orange
(Universidade Federal do Pará, 2003-04-10) LIMA, Edgar Alexandre Reis de; LIMA, Waterloo Napoleão de; http://lattes.cnpq.br/1229104235556506
Acesso aberto (Open Access)
Caracterização faciológica de sedimentos glaciais da formação cabeças na borda sudoeste da Bacia do Parnaíba
(Universidade Federal do Pará, 1997-02-19) OLIVEIRA, Marcelo José de; CAPUTO, Mário Vicente; http://lattes.cnpq.br/1028384858323270
Acesso aberto (Open Access)
Caracterização geoquímica de sedimentos de fundo da orla de Belém-PA
(Universidade Federal do Pará, 2001-09-14) PEREIRA, Kátia Regina de Brito; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
Acesso aberto (Open Access)
Comportamento de metais pesados e nutrientes nos sedimentos de fundo da Baía do Guajará e Baía do Marajó
(Universidade Federal do Pará, 2010-01-28) HOLANDA, Nielton de Souza; ANGÉLICA, Rômulo Simões; http://lattes.cnpq.br/7501959623721607
Human activities influence the physical and chemical characteristics of water, sediments and organisms in aquatic environments located in industrialized areas and high population density. With the increasing use of estuaries as a reservoir for a large amount of waste, coastal and estuarine ecosystems are gradually being subject to significant impacts. The bottom sediments play an important role in the investigation of these impacts since it has the ability to retain chemical species and inorganic. The objective of this research is to study the geochemical behavior of metals in the bottom sediment of the Bay of Guajará, Guama River and the Bay of Marajo. The two regions were chosen for their opposite characteristics: a Guajará Bay Area (1) under strong anthropogenic influence and Marajó Bay Area (2) considered the reference. We collected 83 points in Area 1 and 60 points in Area 2. Determined chemical concentrations of the following metals: Ba, Cr, Cu, Fe, Pb, Ni, V and Zn, and also the levels of nitrogen, carbon, organic matter, total phosphorus and phosphorus bound to organic compounds. Area 1 shows the average content of nitrogen of 0,08 %, mean levels of carbon and organic matter from 1,51 % and 2,60 %, respectively. The concentration of phosphorus and phosphorus bound to organic compounds 307 mg / kg and 126 mg / kg, respectively. The concentration of metals showed the following values: Ba (529 mg / kg), Cr (91 mg / kg), Cu (17 mg / kg) , Fe (6,82 %), Ni (32 mg / kg), Pb (27mg / kg), V (120 mg / kg) and Zn (69 mg / kg). Area 2 shows the average content of organic matter 1.70 % of carbon and nitrogen 0,98 % and 0,08 % respectively. The concentration of phosphorus and phosphorus bound to organic compounds 193 mg / kg and 7 mg / kg, respectively. The concentration of metals showed the following values: Ba (596 mg / kg), Cr (102 mg / kg), Cu (21 mg / kg) , Fe (8,31 %), Ni (40 mg / kg), Pb (28 mg / kg), V (141 mg / kg) and Zn (85 mg / kg). The carbon and phosphorus (0,98 %, 193 mg / kg), respectively found in area 2 were lower than those found in area 1 (0,51 %, 307 mg / kg) and demonstrate the influence of effluents that are released in the estuary Guajarino. In both areas there is the same downward trend in levels: Fe2O3> Ba> V> Cr> Zn> Ni> Pb> Cu. In area 1 were found higher metal alone while in area 2, with the major averages, the distribution is homogeneous, two areas in the metals has a slight tendency to concentrate where there is a higher content of organic matter.
Acesso aberto (Open Access)
Critérios operacionais para redução da contribuição de sedimentos gerados em pilhas de estéril
(Universidade Federal do Pará, 2018-11-14) COSTA, Glayce Wivyanne Oliveira; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Failure to construct and / or operate sterile piles can lead to significant environmental impacts due to the management of sediments from erosion processes, especially in the rainy season, making it necessary to prepare mitigation plans that take into account the behavior morphodynamic characteristics of the land, as well as the rate of sedimentation or the sediment load that can be incorporated into the watercourses during the different constructive stages of the structures, in order to guarantee the integrity of the flora around the enterprise, as well as to optimize the destination of the tailings and sediments within the space defined for the mining activities. In this sense, this study aims to analyze the process of sterile disposal and solids generation in iron ore sterile disposal cells from open pit mines, thus indicating operational criteria that subsidize the reduction of the contribution of sediment generated in batteries for the environment. In order to carry out this work, a Vale sterile stack was installed in the Mineral Province of Carajás, called PDE NW II, for which a documentary research and critical analysis of the main factors involved in the erosive dynamics of the structure was carried out. In this context, rainfall histories, soil cover classification, size and morphology of the contribution basin are included, as well as the quantification of sediment carried by the structure to downstream portions. The methodology used was efficient, mainly because it was able to correlate cause and effect, in the evaluation of the routines of implantation and operation of the piles, in order to make preventive actions intuitive, in order to minimize the contribution of sediment to the environment.
Acesso aberto (Open Access)
Desenvolvimento da vegetação e morfologia da foz do Amazonas-PA e rio Doce-ES durante o Quaternário tardio
(Universidade Federal do Pará, 2013-11-05) FRANÇA, Marlon Carlos; PESSENDA, Luiz Carlos Ruiz; http://lattes.cnpq.br/0425441943533975; COHEN, Marcelo Cancela Lisboa; http://lattes.cnpq.br/8809787145146228
This work compares the vegetation and morphological changes occurred along the littoral of the Marajó Island, Amazonian littoral, and the coastal plain of the Rio Doce, southeastern Brazil, during the Holocene and late Pleistocene/Holocene, respectively, focused specifically on the response of mangroves to sea-level fluctuations and climate change, which have been identified in several studies along the Brazilian coast. This integrated approach combined radiocarbon dating, description of sedimentary features, pollen data, and organic geochemical indicators (δ13C, δ1₵N and C/N). On coastal plain of the Doce River between ~47,500 and ~29,400 cal yr BP, a deltaic system was developed in response mainly to sea-level fall. The post-glacial sea-level rise caused a marine incursion with invasion of embayed coast and broad valleys, and it favored the evolution of a lagoonal/estuary system with wide tidal mud flats occupied by mangroves between at least ~7400 and ~5100 cal yr BP. Considering the Marajó Island during the early and middle Holocene (~7500 and ~3200 cal yr BP) mangrove area increased over tidal mud flats with accumulation of estuarine/marine organic matter. It was a consequence of the marine incursion caused by post-glacial sea-level rise, further driven by tectonic subsidence. Dry conditions in the Amazon region during this time led to a rise is tidal water salinity and contributed to mangrove expansion. Therefore the effect of relative sea-level (RSL) rise was determinant to the mangrove establishment in the southeastern and northern region. During the late Holocene (~3050 – 1880 cal yr BP) the mangroves in both regions were retracted to a small area, with some areas replaced by freshwater vegetation. This was caused by the increase in river discharge associated to a wet period recorded in the Amazon region, and considering the coastal plain of the Doce River (southeastern Brazil), the mangroves shrank in response to an increase in fluvial sediment input associated to a sea-level fall.
Acesso aberto (Open Access)
Desenvolvimento metodológico e avaliação de contaminação por HPAs em sedimentos da baia de Guajará
(Universidade Federal do Pará, 2014-03-31) SODRÉ, Silvana do Socorro Veloso; CAVALCANTE, Rivelino Martins; http://lattes.cnpq.br/2253127527012522; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants with toxic effects, harmful to the environment and to human health. They are part of a group of persistent organic pollutants (POPs), which by its characteristics have an impact on the environment and are extensively studied for this reason. They may be present in particulate, dissolved and/or gaseous forms, in different environments such as soil, sediment, air, water, particulate matter in the atmosphere, organisms and food (Kennish, 2007). Natural sources of PAHs include volcanic activity, natural fires, oil oozing and biogenic processes. Anthropogenic PAH pollution may occur by incomplete oil combustion (automotive and industrial), intentional burning of wood and plantations, domestic and/or industrial wastewater, urban water flow, accidental spills of oil and derivatives. Hydrophobic and lipophilic, these substances can be easily adsorbed by sediments, so that this matter is an important reservoir for them. To evaluate the presence of these compounds in the environment, this work used High Performance Liquid Chromatography. The samples used in the development and optimization of the methodology were collected in the Guajará bay (Belém - PA). This work consisted in the development of a methodological procedure (with adaptations and optimizations) to quantify 16 PAHs in 10 points in the Guajará bay in two field campaigns, so that 20 samples were analysed. In the development stage of the analytical method, elution systems, system polarity and eluent flow were tested, among others. In order to validate the method, the following parameters were assessed: fidelity, linearity, detection limit and quantification limit. Diagnostic ratios were calculated to identify the primary sources of PAHs found in the bay. The primary sources of the 16 PAHs studied in the sediments of the bay were identified based on ΣPAHs BMM/ΣPAHsAMM; Phe/Ant; Flt/Pyr; Ant/Σ178; Flt/Σ202; B(a)P/Σ228 and Ind(123cd)pyrene/Σ276. In the first field campaign, the total concentration of light PAHs ranged from 132.3 ng.g-1 to 1704.14 ng.g-1, the ΣPAHs of the heavy ones, from 125.82 ng.g-1 to 1269.71 ng.g-1 and the total ΣPAHs, from 317.84 ng.g-1 to 3117.06 ng.g-1. In the second field campaign, the total concentration of light PAHs ranged from 76.12 ng.g-1 to 1572.80 ng.g-1, the ΣPAHs of the heavy ones, from 213.90 ng.g-1 to 1423.03 ng.g-1, and the total ΣPAHs, from 290.02 ng.g-1 to 2995.82 ng.g-1. Based on these results, the Guajará bay can be classified as moderately impacted. The combustion is the predominant source of PAHs in the sediments of the bay, followed by vegetal biomass combustion and by the contribution of oil and supplies. Most of the points studied in this work, during the two field campaigns, showed concentrations of individual PAHs above the SQGs.
Acesso aberto (Open Access)
Distribuição de metais pesados e isótopos de Pb em sedimentos do rio Amapari, setor de Pedra Branca do Amapari – Porto Grande, Amapá
(Universidade Federal do Pará, 2011-03-18) SILVA, Danúbia Tavares da; LAFON, Jean Michel; http://lattes.cnpq.br/4507815620234645
This work consists of a geochemical study of heavy metals and Pb isotopic signature of sediments from the hydrographic basin of the Amapari river, which is the main affluent of the right edge of the Araguari river, in the central region of Amapá State. The study is more precisely located in a part of the river, close to the Serra do Navio area, between the cities of Pedra Branca do Amapari and Porto Grande. The region hosts the larger mining district of Amapá, including two important gold and iron mines at the Serra do Navio. The aim of this work is to investigate the distribution of heavy metals and other metals like Al, Fe, Th and U, together with the determination of Pb isotopic composition of recent sediments that are sediments deposited at the superior edge of the river during inundation events (overbank sediments), sampled along the Amapari river and tributaries, in order to distinguish the natural contributions from the main geological units and a possible contribution of mining activities. The sampling strategy depended on two factors: (1) the occurrence of adequate outcrops and (2) the accessibility. The sediments, collected at 25 sampling points in November, 2007, include a set of samples from the Amapari river and three sets of samples collected in tributary of the right edge (Cachorrinho river and Cupixi river) and left edge (Cupixizinho river). In all the samples, granulometric, mineralogical, chemical and isotopic analyses were performed. The granulometric analyses were effectuated in order to determine the proportions of fine material (silt + clay) and clay. The mineralogical composition was determined by Xrays Diffractometry using a X-rays diffractometer with cobalt anode tube. The determination of major end trace elements contents has been carried out at a commercial laboratory (ACME Analytic Laboratory) by ICP-EOS and ICP–MS after four acids dissolution (HF + HCl + HClO4 + HNO3) in 8 whole samples and 22 samples of the fine fraction of the sediments. The elements of major interest were: Al, Fe, Pb, Mn, Cu, Zn, Ni, As, Cd, Cr, Th e U. For the isotopic analyses, the samples suffered total digestion with HF and HNO3+HCl (20 samples) and acid leaching with HNO3 (5 samples). The Pb separation and purification were achieved by ionic exchange chromatography (1x8 DOWEX resin). The Pb isotopic compositions were determined in static mode with a multi-collector thermal ionisation mass spectrometer Finnigan MAT262 at the Pará-Iso Laboratory of the IG-UFPA. The geochemical results indicate that all heavy metals behaved similarly and are enriched in the same samples, indicating that the sediments suffer the same processes of enrichment for all investigated heavy metals, excepting cadmium that displayed a different trend. No relationship between granulometry and heavy metals content was pointed out. Thus, the proportion of clays presents in the sediments does not appear to have been preponderant for heavy metals concentrations, at the contrary of that commonly occur in bottom sediments. Not significant variation of mineralogical composition has been observed between the fine fraction and the fraction superior to 62μm that account for the similarity of the chemical compositions between those fractions. In both granulometric fractions, the same main paragenesis composed by quartz, kaolinite, gibbsite and muscovite was identified. Other minerals were recognized in some of the samples (anatase, rutile, microline, etc.), which probably belong to the primary paragenesis. The presence of these minerals does not have influence on the heavy metals concentrations. The heavy metals contents furnished a better correlation with Fe than with Al contents although Fe-minerals were not been identified in the samples. The Pb isotopic compositions displayed significant variations and linear rend that permitted to construct isochrons in the 207Pb/204Pb vs. 206Pb/204Pb diagram, which defined Paleoproterozoic ages around 2,0 Ga, (Amapari river: 1964 ± 88 Ma, mswd = 1,6), indicating that the sediments came essentially from the Paleoproterozoic supracrustal units (metassedimentary and mafic rocks) and associated granitoids. Despite its extensive exposition in the area, the Archean basement does not significantly contribute as a source of the sediments. The concentrations of metals display strong variations according to the geographical location but they are randomly distributed along the Amapari river, indicating that homogenization does not occurred and that the sediments reflect the difference in the source rocks. Therefore the processes which account for that geochemical distribution are probably naturals as no was evidenced no correlation has been evidenced between metal contents and sample locations in relation the mining areas. The comparison between metals contents of the Amapari river and tributaries and those determinate by others authors in bottom sediments of a creek close to the Fe and Au mining plants of the Serra do Navio – Pedra Branca do Amapari confirms that hypothesis.
Acesso aberto (Open Access)
Distribuição do mercúrio em sedimentos de fundo no Estuário de Santos SP/Brasil
(2005-12) SIQUEIRA, Gilmar Wanzeller; BRAGA, Elisabete de Santis; PEREIRA, Simone de Fátima Pinheiro; SILVA, Elisamar da
Bottom sediment samples were collected and analyzed for mercury in the Estuary of Santos-SP. The analytical results reveal anthropogenic contamination for some sectors of this estuarine area as a result of petrochemical and metallurgical residues derived from the Industrial District of Cubatão, from the activities of the State of São Paulo Siderurgy (COSIPA), from the Santos harbor and, finally, from effluents discharged by the submarine emissary into the Bay of Santos. The values for the factor of contamination (FC) found in the bottom sediments range from 1 to 3, mainly for the channels of Santos and São Vicente; however, in the Bay of Santos the FC values (below 1) indicate low contamination except in the discharge area of the submarine emissary.
Acesso aberto (Open Access)
Distribuição e registro histórico de metais pesados e assinaturas isotópicas de PB em testemunhos de sedimentos de fundo da Baia do Guajará, Belém-PA
(Universidade Federal do Pará, 2011-08-29) CARVALHO, Jully Hellen dos Santos; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568; LAFON, Jean Michel; http://lattes.cnpq.br/4507815620234645
tuaries constitute the final destination of a significant part of dissolved and particulate materials that are brought by the rivers toward the ocean. These estuaries also act as the final destination for domestic and industrial effluent, which are most of time discarded in natura. A variety of factors and sources together with the complexity of hydrodynamics and physicochemical conditions of this kind of environment makes the study of metals pollution of estuaries a challenge. The analysis of Pb isotopes is a valuable tool to differentiate anthropogenic from geogenic sources, since the lead dispersed in the environment keeps the isotopic characteristics of the source from which it was derived, once the isotopic compositions of Pb are not affected by physical or chemical processes. The hydrographic system of Belem (PA) belongs to the Guajara estuary. In the eastern margin, is located the Belém city. The west margin is an islander set composed 39 islands. About 30 km of natural drainages divide the city, forming channels that drain into, above all, the Guajara Bay which constitutes the main water reservoir receiving pollutants produced by domestic and economic activities of the city. However, the distribution of pollutants released daily in the bay is difficult to be evaluated, due to the hydrodynamic complexity of the estuary. In this context, the purpose of this study was to combine the determination of metal concentrations with Pb isotope signature to establish a historical record and to distinguish the sources of Pb, whether natural or anthropogenic, in sediments on the west edge of Guajará Bay. Samples were collected using a Russian Peat Borer. A set of seven cores of about 50 cm length was collected and subsequently sliced from 10 to 10 cm, totalizing 31 samples. According to the speed of deposition of approximately 0.7 cm/year, previously determined for the sediments of Guajara bay with geochronology 210Pb, cores collected correspond to a historical record of approximately 70 years. The study included grain size study by centrifugation method, mineralogical identification by X-ray diffraction, geochemical analysis to determine the percentage of organic matter and heavy metal contents by ICP-MS spectrometry and isotopic mass spectrometer thermoionization (TIMS). The grain size and mineralogical study of core in bottom sediments from the west edge of the Guajará bay showed a changing of hydrodynamic regime, which became more energetic, throughout the bay over time. This statement was based on the characterization of sediments, which show predominance of silt and sand fraction with a reduction of the sand fraction with the depth and texture that ranged from sandy to sandy-silty. The mineralogical study no showed change in mineralogical composition of the clays, and kaolinite, illite and smectite are claysminerals predominant. Over time the concentrations of metals vary little, however, have detected a slight tendency to decline in more recent times, probably linked to changes in the hydrodynamic regime. Moreover, there is no evidence in the core of a significant a significant increase in metal concentrations (mean 25.3 to 29.1 mg.Kg-1) with the population increase over the last 70 years. These results indicate that the background of Pb in the bay is significantly higher than in rio Guama (18 mg.Kg-1). The isotopic composition of source 206Pb/207Pb geogenic over the cores ranged between 1.186 and 1.199. The average isotopic signature of 1.193 ± 0.0035 was established as the value of the background to the Guajará bay, this value lower than the average value of 1,196 - 1.20 previously determined for the isotope ratio 206Pb/ 207Pb of Pb geogenic in Belém region.The differences in content and isotopic composition of Pb between this study carried out by Saraiva (2007) and Nascimento (2007) on the west edge of the bay, were explained by the difference of the technique used for sampling. This difference indicated that, despite the population growth accelerated during the last decades the contribution of heavy metals by anthropic action is recent, intensifying over the last 7 years.
Acesso aberto (Open Access)
Distribution and isotopic composition of lead in bottom sediments from the hydrographic system of Belém, Pará (western margin of Guajará Bay and Carnapijó River)
(Universidade Federal do Pará, 2016-06) OLIVEIRA, Elma Costa; LAFON, Jean Michel; CORRÊA, José Augusto Martins; CARVALHO, Jully Hellen dos Santos
This study first aimed to evaluate the effect of human activities on the distribution of lead within the estuarine system of Belém, Pará. This was achieved by studying the concentration and isotopic signature of Pb in bottom sediments from the western margin of Guajará Bay and from Carnapijó River, an area removed from the influence of the city of Belém. Secondly, the contribution of suspended matter in the transportation of anthropogenic Pb in Guajará Bay was evaluated. Third, the content and background isotopic signature of Pb in the hydrographic system of Belém was determined. Isotopic signatures of sediments from the western margin of Guajará Bay confirm an anthropogenic contribution of Pb throughout the entire bay. The Pb accumulation process has become more efficient over the last 10 years, and this can be attributed to the rapid population growth of Belém city. Sediments in Carnapijó River are not affected by human activities, and the average concentration values (Pb = 19.6 ± 3.7 mg kg-1) and isotopic signatures (206Pb/207Pb = 1.196 ± 0.004) confirm the background Pb values previously proposed for the river system in the Belém region. The isotopic signatures of suspended matter on the eastern (206Pb/207Pb = 1.188) and western (206Pb/207Pb = 1.174) margins of Guajará Bay show that suspended matter is an efficient Pb transportation mechanism of domestic and industrial wastewater from Belém to the western margin of the Bay due to tidal effects at the confluence with Guamá River.
Acesso aberto (Open Access)
Esteróides como biomarcadores de contaminação orgânica em sedimentos superficiais e testemunhos do Estuário Guajará-PA
(Universidade Federal do Pará, 2012-06-13) GOMES, Heyde Gonçalves; SOUZA FILHO, Pedro Walfir Martins e; http://lattes.cnpq.br/3282736820907252; KAWAKAMI, Silvia Keiko; http://lattes.cnpq.br/5306256489815710
The city of Belém of Pará, its surroundings and body waters are subject to environmental impacts due to the increase of local population and poor sanitation conditions. The Guajará bay receives untreated sewage effluents from Belem’s catchment area, which is of concern to public health and environmental quality. This study aimed to identify organic contamination in surface sediments and sediment cores of the Guajará estuary using steroids as biomarkers. Steroids have been used since 1960 as tracers of natural and anthropogenic organics in the aquatic environment, however, studies using such compounds in the northern region of Brazil is new. Therefore data from other regions were important for comparison and to improve our knowledge about the composition of organic matter in the Guajará Bay. Samples of surface sediments and sediments cores (~50 cm) were collected in January 2011. The sediments cores were taken from Tucunduba, Icoaraci. Surface sediments were collected in Tamandaré, Porto da Palha, Ver-o-Peso, and Miramar. Steroid analyses were performed using gas chromatography with flame ionization detection. Sediments were subsampled for analysis of chlorophyll, total organic carbon and grain size. Several steroids were identified (coprostanol, cholesterol, epicoprostanol, colestanol, colestanona, coprostanona, estigmasterol, brassicasterol, β-sitosterol, β-sitostanol), from both natural and anthropogenic sources. Concentrations of coprostanol, an sterol of fecal origin, in surface samples ranged from 0.06 to 5.61μg g-1 and in the sediments cores of Tucunduba, 0.02 to 11.23 μg g-1 and Icoaraci 0.03 of 0.31 μg g-1. For the surface sediment samples, highest coprostanol concentrations were observed at Ver-o-Peso, in contrast to the high sand content of the sediments. For the sediment cores, two different profiles were observed: for Tucunduba the steroids that predominated at high concentrations within the top layers were coprostanol, coprostanona, colesterol e colestanol, which indicated recent sewage inputs. For Icoaraci, brassicasterol, estigmasterol, sitosterol e sitostanol, steroids of plant sources predominated at higher concentrations. Absolute coprostanol concentrations and steroid concentration ratios indicated that most of the sampling sites were contaminated by untreated sewage. The use of steroid ratios to understand the results was also important to minimize the dependence of the steroids to organic carbon content and granulometry.
Acesso aberto (Open Access)
Estudo da composição isotópica de Pb em organismo bentônicos, poliquetas (Namalycastis abiuma) e oligoquetas, da Baía do Guajará e rio Guamá
(Universidade Federal do Pará, 2009-06-24) OLIVEIRA, Simone Pereira de; ROSA FILHO, José Souto de; MOURA, Candido Augusto Veloso; http://lattes.cnpq.br/1035254156384979
In Guajará bay (Terminal Petroliferous do Miramar and mouth of Una Canal) and in Guamá river (mouth of Tucunduba creek), three samples of bottom sediments, three of polichaetes (Namalycastis abiuma) and five samples of oligochaetes (Tubificidae) were collected. In the biological samples lead (Pb) concentration and isotope composition were determined, whereas in the sediments samples only the Pb isotope composition was. Pb content was quantified in two representative samples of oligochaetes and polichaetes. Concentrations of 5 mg.kg-1 and 3 mg.kg-1, was obtained for these organisms, respectively. Pb concentration determined in oligochaetes was equivalent to 13% of the lead’s level of the bottom sediments of its habitat (38 mg kg-1). In spite of the Pb content of the bottom sediments of Guajará bay may suggest moderate pollution, this proportion can be considered high when it is compared with the percentual relation of 1,7% of oligochaetes and sediments of very polluted environments (p. ex. botton sediment lakes of India with lead content reaching 2.260 mg.kg-1 and oligochaetes with until 23 mg.kg-1). This result suggests that, proportionally, oligchaetes may assimilate greater amount of lead of its habitat in less polluted environments. However, the lead level in oligochaetes compared with the lead level in sediments of its habitat, showed a positive correlation, and it indicates that oligochaetes can be used as a bioindicator. The polychaetes (Namalycastis abiuma), did not show a trend that indicates any type of connection or correlation between lead level in organisms and lead level in sediments. This result indicates that polichaetes cannot be used as bioindicator of the enrichment of lead (and metals) in its habitat. Lead isotope composition of the bottom sediments in Guamá river, gave the value of 1,193 for the 206Pb/207Pb ratio which is different to the suggested a value of 1,194 for the bottom sediment of the Guamá river, and interpreted as the natural value (geogenic). This indicates a anthropogenic origin of lead in Guamá river in the sampled point (mouth of the Tucunduba creek). In Guajará bay, the sample of sediment in the mouth of the Una Canal, presented a value of 1,167 for the reason 206Pb/207Pb. In previous works, this value had been suggested as indicative of lead of anthropogenic origin. This value of 206Pb/207Pb ratio shows that the Una canal is contributing to lead level in the sediments of the Guajará bay, through of discharge of domestic effluent and solid residues. Finally, in a sediment sample collected in the Terminal Petroliferous do Miramar, also in the Guajará bay, the value of the 206Pb/207Pb ratio was 1,188. This value is lower than that suggested as natural value of the 206Pb/207Pb ratio in the bottom sediments of the Metropolitan Region of Belém, which is of 1,200. This lower value can be related to activities of the Terminal Petroliferous do Miramar. The products originated in oil have an important potential of heavy metal (including lead) dissemination to environment. In order to compare the lead isotope signature of the organisms with that of the sediments the values of the isotopic ratio 206Pb/207Pb of the organisms were divided by the respective values of thIs ratio in the sediments. If the resultant quotient, represented as R, had a value of 1± 0,004 (0,996 ≤ R ≤ 1,004), it was considered as indicative that the lead isotope signature of the organisms reflected the signature of the bottom sediments of its habitat. The values of R in 75% of the biological samples were within the interval (0,997 ≤ R ≤ 1,001). The other 25% that remain outside of this tolerance interval, correspond to the two samples of oligoquetas collected in the mouth of Una Canal. Thus, the three samples of polichaetes collected next to the Terminal Petroliferous do Miramar, and the three samples of oligoquetas collected in the Guamá river next to the mouth of Tucunduba creek show values of R within the tolerance interval. This suggest that the polichaetes (Namalycastis abiuma) and oligochaetes reflected the lead signature isotope of the environment in which they are inserted, and are good bioindicators of lead isotope composition in its habitat.
Acesso aberto (Open Access)
Estudo do comportamento de metais pesados nas frações < 2 μm e < 63 μm nos sedimentos de fundo do rio Arienga – Barcarena – Pará.
(Universidade Federal do Pará, 2011-05-18) MENEZES, Helenice Quadros de; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
The bodies of surface water in large urban centers and industrial have been under increasingly the impact of human action. What cause other environmental problems among the input content of heavy metals that accumulate in bottom sediments, causing serious damage to the aquatic system. In order to study the level of contamination of bottom sediments of the river Arienga important river city Barcarena – PA, and evaluate possible contamination by toxic wastes from the steel industry the industrial hub of the city were analyzed for textural, mineralogical and chemical in nine samples collected along the river and one at the mouth of the creek Bacabal. The results of the sediment grain size showed the predominance of silt over the others (sand and clay). Only the first three points collected by virtue of proximity to the mouth, was the predominant sand fraction. O mineralogical study of samples revealed an essentially quartzose fraction < 63 μm and the presence of kaolinite, smectite and illite in the fraction < 2 μm. The organic matter analysis showed an average of 5.90±1.87 mg.Kg-1. Analyses for determination of trace elements was carried out both in the fraction < 63 μm and in the fraction < 2 μm. It was observed that there was a considerable enrichment of heavy metals in the finer fraction of sediment (< 2 μm): Ni increased from an average of 11.10 ± 1.89 mg.Kg-1 in the fraction < 63 μm for a average of 37.94±1.94 mg.Kg-1 in the fraction < 2 μm; Pb increased its average 14.61±2.37 mg.Kg-1 to 46.02±2.49 mg.Kg-1, the Zn concentration increased from an average of 41.60±6.33 mg.Kg-1 to 107.40±7.78 mg.Kg-1, the Cu concentration increased an average of 12.38±2.28 mg.Kg-1 to 30.37±5.70 mg.Kg-1, for V, Co and Ba increase in the average concentration was respectively of 92.10±9.35 mg.Kg-1, 9.08±1.45 mg.Kg-1 and 344.70±46.76 mg.Kg-1 to respectively 140.80±7.19 mg.Kg-1, 16.82±1.58 mg.Kg-1 and 428.50±36.81 mg.Kg-1. Getting a clear affinity for all metals analyzed with the clay. The determination of the Index of Geoaccumulation (IGeo) showed that the river Arienga, although situated in an area of risk, isn’t contaminated to the metals studied, and therefore the values found were probably due to local geology.
Acesso aberto (Open Access)
Estudo dos cátions cálcio, magnésio, sódio, potássio e da salinidade na água intersticial do sedimento do manguezal de Bragança - NE do Pará
(Universidade Federal do Pará, 2000-08-01) COSTA, Marlene Furtado da; RAMOS, José Francisco da Fonseca; http://lattes.cnpq.br/8189651755374537
Desconhecido
Estudo sedimentológico dos sedimentos Barreiras, Ipixuna e Itapecuru no nordeste do Pará e noroeste do Maranhão
(Universidade Federal do Pará, 1981-06-24) GÓES, Ana Maria; TRUCKENBRODT, Werner Hermann Walter; http://lattes.cnpq.br/5463384509941553
Barreiras, Itapecuru and Ipixuna are exposed in large regions of Pará and Maranhão State. The Barreiras sedimente are divided in conglomeratic, sandy clay and sandy lithofacies. Textural imaturity and abundant mud-s.upported clastics in particular, suggest depositions mainly by debris flows under semiarid conditions. The three lithofacies were probably derived from Precambrian schists of Santa Luzia Formation and preexisting sedimente. The Itapecuru sedimenta consist of crossbedded sandstones, locally with minor conglomerates and mudstones, deposited in fluvial environment, probably tending to a semiarid conditions. The Ipixuna facies consiste of crossbedded kaolinitic sandstones, minor mudstones (lithology A) and laminated mudstonefine sandstone units including thick kaoline layers (lithology B). The fine sandstones are texturally and mineralogically mature. Lacustrine-fluvial origin is proposed for Ipixuna facies. The impoverished heavy-mineral assemblage and thick kaoline-layers suggest humid hot climate that probably prevailed before (during?) the Ipixuna sedimentation. Textural and structural characteristics of the sedimente studied show that there is a olear difference between Barreiras Group and Ipixuna facies and that the latter is correlated with the Itapecuru Formation. Bauxitization of lower Tertiary age affected only the Ipixuna and Itapecuru sedimentary rocks.
Desconhecido
Estudo sedimentológico e geoquímico em sedimentos de fundo na Baía de Guajará-Belém (PA)
(Universidade Federal do Pará, 2007-08-28) SARAIVA, André Luis de Lima; TRUCKENBRODT, Werner Hermann Walter; http://lattes.cnpq.br/5463384509941553
During the last years, many Brazilian estuaries located close to great cities have been suffered several environmental alterations caused by the accelerated and disordered growth of these cities. These alterations may occur from heavy metals that reach the water bodies being adsorbed by the sediments. In this context, the bottom sediments play an important role, because they can work as indicators of the level of pollution of these environments, becoming still more relevant when anthropic processes are considered. With the objective to evaluate the degree of contamination of the sediments from the Guajará bay, mainly in areas close to the margin of the Onças, jaraquinha, Mirim and Jutuba islands and also close to the Val de Cans channel, sedimentological, mineralogical and chemical analyses were carried out from bottom surface sediments and cores of about 50 cm depth. The identified sedimentary facies in the cores were sandy mud with thinly evenparallel rhythmitic bedding, sandy mud with cross lamination, sandy mud with longitudinal cross bedding and wavy lamination. These structures, particularly the evenparallel rhythmitic bedding and the longitudinal cross bedding, indicate tidal influence and lateral channel migration, respectively. The grain size results of the analyzed bottom surface sediments showed the dominance of sandy silt and silty sand and only one sample has been classified as sand. The mineralogical study defined the presence of quartz, kaolinite, illite, smectite and heavy minerals which include staurolite, tourmaline, rutile, kyanite, zircon, epidote, amphibole (hornblende) and sillimanite, being the most abundant minerals tourmaline, kyanite, staurolite, zircon and rutile. With the exception of epidote and hornblende which suggest direct provenance (first cycle) from metamorphic/igneous rocks, the other minerals seen to be derived from recycled Barreiras and/or Post-Barreiras sediments. The analyses of organic matter and the chemical analyses of the bottom sediments provided the following average concentrations: Organic matter 1,87±0,84%; heavy metals Pb 33,3±4,9 mg.kg-1; Cr 59,7±8,3 mg.kg-1; Co 10,8±2,2 mg.kg-1; Ni 19,3±4,4 mg.kg-1; Zn 73,7±15,1 mg.kg-1; Cu 18±2,8 mg.kg-1; Mn 489,2±166,5 mg.kg-1 and Fe 3,6± 0,6% The chemical results obtained from three cores are not very different from those of the bottom surface sediments, with the exception of Pb and Zn whose mean values are lower in the cores. How one could expect, a significant correlation has been obtained between the metals and Al which stands for the clay minerals. All the concentrations of the analyzed metallic elements in the bottom sediments of the Guajará are lower than their PEL index which represent the concentration above which adverse effects on biota are expected to occur frequently. In the surface sediments all Cr and some of the Ni and Pb values are higher than the TEL index, which represent the concentration below which adverse effects are expected to occur only rarely, whilst in the cores only the Cr and some Ni values surpass the TEL index. Pb, Cr and Ni of the bottom surface sediments suggest anthropogenic influence, but at present their values do not represent any risk for the estuarine environment.