01. Universidade Federal Rural de Pernambuco - UFRPE (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/1
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Resultados da Pesquisa
Item Aplicação da técnica de espectrometria de fluorescência de raios-x por dispersão de energia (EDXRF) para a quantificação de metais pesados em sedimentos de fundo(2025-02-26) Silva, Ingrid Coimbra da; Gomes, Maria José de Filgueiras; França, Elvis Joacir de; http://lattes.cnpq.br/1716496767364751; http://lattes.cnpq.br/0060810526769648; http://lattes.cnpq.br/9997365922939570Estudos recentes do monitoramento dos ecossistemas aquáticos retratam a relevância de tornarem os sedimentos de fundo como objeto de estudo dos impactos de contaminação ambiental por serem acumuladores, processadores e transportadores de metais pesados e espécies contaminantes. Nesse sentido, este presente estudo teve o objetivo de avaliar a aplicabilidade da técnica de Espectrometria de Fluorescência de Raios X por Dispersão de Energia (EDXRF) na quantificação dos elementos químicos Mn, Fe, Ni, Zn, Sr, Ti, Al, Si, K, Ca, V e La e avaliação da qualidade do sedimento a partir dos valores orientadores TEL e PEL de concentração estabelecidos pelo CCME (Canadian Council of Ministers of the Environment) e adotados pela CETESB para os elementos Ni e Zn como possíveis contaminantes em 52 amostras coletadas de 4 perfis de sedimentos originadas da Costa Brasileira, cedidos pela Pesquisa Desenvolvimento Inovação e Ensino (PDIE) ao Centro Regional de Ciências Nucleares do Nordeste (CRCN/NE). A natureza da pesquisa foi do tipo aplicada baseada em uma abordagem quantitativa através das médias aritméticas das concentrações dos metais pesados pelo EDX-720 e materiais de referências certificados (IAEA-SL-1) comparados com valores obtidos e certificados. O tratamento dos dados foi realizado mediante a metodologia de Fernández (2017) e o cálculo de incertezas analíticas com intervalo de 95% de confiança pela metodologia de Costa (2023). De maneira geral, o elemento Ni apresentou valores acima de TEL para a maioria dos pontos analisados, resultando na classificação de qualidade regular dos sedimentos analisados. O metal Zn esteve entre TEL e PEL para a maioria dos pontos coletados, sendo classificada a qualidade do sedimento como ótimo para esse elemento. As concentrações dos demais elementos não apresentam valores guias para comparação. Dessa forma, os objetivos deste trabalho foram atingidos e apresentaram relevância para a justificativa da aplicabilidade da técnica de EDXRF para o estudo de sedimentos de fundo e a importância da avaliação ambiental pela contaminação de metais pesados e seus impactos para os ecossistemas aquáticos causados pela ação antrópica ao longo dos anos.Item A experimentação no ensino de Química: análise de uma proposta de sequência didática para o ensino do conteúdo de metais pesados(2024-09-27) Lima, Isabela Januario de; Silva, Suely Alves da; http://lattes.cnpq.br/3497194749381919Chemistry and the knowledge it provides are extremely important for humanity since its beginning. Learning it provides the students comprehension about the most variable chemical transformations that happen around us. Teaching Chemistry can be challenging for various teachers that have troubles in getting attention from its students for this science, since it has very abstract characteristics and of tough comprehension. In this regard, practical pedagogics are needed to help catch the students’ attention on this science, and one way of achieve that goal is by practical experiments. The general goal of this research was to analyze a didactical sequence utilizing the experimentation as a methodology strategy for the teaching about the Heavy Metals. The utilization of practical activities in the teaching of Chemistry shows as a good strategy to simplify and enthrall the students in the process of learning so that they can articulate the theoretical concepts with practical experiments. This research shows the analysis of a didactical sequence about of using practical experiments when teaching about Heavy Metals. It shows the benefits that practical activities brought while learning the subject, as well the development of scientific abilities. The acquired data were analyzed in an articulated way along with the authors of the theoretical foundation under a qualitative perspective. The tools utilized were two questionnaires, one applied before the experimental activity, and a problem situation to conclude activities carried out afterwards. The research brought many positive outcomes, as a bigger participation of the students and a better comprehension of the same about the Heavy Metals and their characteristics. The engagement and curiosity about this specific subject and about clothes questions that involves chemistry in the experimental part of this science. In conclusion the experiment is one strategy that provides an improvement in the process of teaching and contributes to a bigger engagement of the students in the class, stimulating the curiosity of this science.Item Avaliação da contaminação por metais pesados em solos urbanos da Região Metropolitana do Recife: bioacessibilidade e correlação com NDVI(2024-03-07) Mello, Lucas José Souza de; Biondi, Caroline Miranda; Lins, Simone Aparecida da Silva; http://lattes.cnpq.br/7329862411748916; http://lattes.cnpq.br/8326756664758702; http://lattes.cnpq.br/8741487779369891Urban pollution by heavy metals is a subject of great socio-environmental relevance due to its potential deleterious effects on human and ecological health. Remote sensing, particularly the use of the Normalized Difference Vegetation Index (NDVI), emerges as a promising tool to assess vegetation health and potential impacts of soil contamination. In this regard, the present study aimed to evaluate the total contents and bioaccessibility of heavy metals in urban soil of the Recife Metropolitan Region and its chemical characteristics, obtain the NDVI of the sampled areas, and correlate it with the total metal contents analyzed. The research was conducted in the Recife Metropolitan Region (RMR), where samples of surface soil were collected in distinct urban areas and their points were georeferenced. The samples were analyzed for pH values, Organic Carbon, Soil Cation Exchange Capacity (CTC), and total heavy metal contents using Energy Dispersive X-ray Fluorescence (pXRF). Metal contents were compared with Quality Reference Values, and in vitro assays were performed to determine metal bioaccessibility in the soil. For NDVI estimation, images obtained from the CBERS-4A satellite with 8m spatial resolution were used, and buffers with radii of 55, 110, and 220m were applied to demarcate the area to be analyzed based on the sampled points. The results revealed high levels of heavy metals in urban areas of the RMR, exceeding the Quality Reference Values for the state of Pernambuco, yet the metals exhibit low bioaccessibility. Regarding the size of the analyzed area, there was no significant difference in relation to the values obtained. Additionally, a negative correlation was observed between most soil metal contents and NDVI, meaning that as NDVI increases, metal contents decrease.Item Teores de mercúrio total e estimativa de risco à saúde humana em solos de manguezal contaminados por indústria de soda-cloro(2024-02-26) Silva Neto, José Carlos da; Biondi, Caroline Miranda; Araújo, Paula Renata Muniz; http://lattes.cnpq.br/1779598476646308; http://lattes.cnpq.br/8326756664758702; http://lattes.cnpq.br/5393117310370821The Botafogo River estuary is located between the cities of Goiana and Itapissuma, coastal area of Pernambuco, and is the most relevant water resource among the coastal rivers that border the region, being responsible for the main water reservoir used to supply the local population. However, the activity of a chlor-alkali plant established close to the mangrove in the 1960s brought effluents containing Hg into the river, presenting potential for contamination in areas of mangrove forests, which could interfere with the health of the mangrove ecosystem and the community. This work aimed to evaluate the total Hg levels, relate them to the granulometry and chemical attributes of the soils and estimate the risk to human health in soils from two transects, located in different physiographic positions of the Botafogo River mangrove. For this, 3 soil profiles (0-40 cm) were collected at distances 0, 60, 120 and 180 meters from the margin of each transect during periods of low tide. The profiles were sectioned at depths 0-5, 5-10, 10-20, 20-30 and 30-40 cm and the particle size fractions, organic matter, pH, Eh and total Hg were determined. Based on the Hg results in the soils, the non-carcinogenic risk to human health was estimated. The pH and Eh values indicated slightly acidic to neutral soils and suboxic to anoxic environments, respectively, representing favorable conditions for Hg retention. Clay content predominated in the soils of Transect 1 (T1), while the sand fraction predominated in Transect 2 (T2). SOM values ranged from 144 to 424 g kg-1, with higher levels in the T1 profiles. Average Hg levels ranged from 0.2 to 15.3 mg.kg-1 in T1 and from 0.0 to 7.4 mg.kg-1 in T2. The Hg contents in T1 were higher compared to T2, possibly due to the position of the transect in the landscape and the greater accumulation of clay and OM, corroborated by the positive and significant correlations between Hg and clay, and between Hg and OM. When comparing the Hg values found with international reference levels, maximum Hg values were found to be up to 102 times higher than the international reference value TEL (Threshold Effect Level) and 15 times the PEL (Probable Effects Level). About 82% of samples exceeded the PEL, indicating that toxic effects on biota are likely. The health risk for children was greater than that for adults because they are organisms more sensitive to the toxicity of the metal. The main route of exposure was inhalation of Hg vapor. Contamination of soils in the Botafogo River estuary reached mangrove forest areas, highlighting the widespread Hg contamination in the area. The areas most contaminated by the metal pose risks to the riverside community.Item Adsorção dos íons metálicos Cu2+ e Mn2+ em sistema bicomponente utilizando carvão ativado preparado a partir de sabugo de milho como adsorvente(2022-05-20) Campos, Natália Ferreira; Moraes, Alex Souza; Duarte, Marta Maria Menezes Bezerra; http://lattes.cnpq.br/2069994676017059; http://lattes.cnpq.br/0440163845324480; http://lattes.cnpq.br/7441229690485153Heavy metals are used in several areas, especially in the pulp and paper industry, since their effluents contain high levels of copper and manganese, which can cause harmful effects on living systems due to their toxic nature, non-biodegradable and accumulate in organisms. This problem has led several research groups to seek treatment alternatives. Adsorption using activated carbon prepared from agro-industrial residues has been presented as an alternative for the treatment of effluents containing heavy metals. In view of the above, this work proposes the use of activated carbon prepared from corn cob as an adsorbent for the removal of Cu2+ and Mn2+ metallic ions in mono and bicomponent systems. Corn cob activated carbon was chemically activated with H3PO4. The characterization of corn cob and activated carbon was carried out by Fourier transform infrared spectroscopy, Boehm titration and determination of the pH of the zero charge point. The influence of the initial pH of the solution on the adsorptive process was studied in order to determine the pH used in further studies. Based on the results obtained, kinetic and adsorption equilibrium studies were carried out for the mono and bicomponent systems. The characterization indicated that the activation promoted an increase of carboxylic groups on the surface of the adsorbent, reduction of the pHZCP value from 4.7 in the corn cob to 3.0 in the activated carbon, increasing the pH range of the solution in which the surface of the coal becomes negatively charged, which favored the adsorption of Cu2+ and Mn2+ ions. In the study of the effect of the initial pH of the solution in a single-component system, pH 4 and 6 showed better results for Cu2+ and Mn2+ ions, respectively, whereas in the bicomponent system it was pH 4. The model that best represented the experimental data of the kinetic evolution was the pseudo-second order for monocomponent systems and for Cu2+ in the bicomponent system, while for Mn2+ it was the pseudo-first order model. In the adsorption equilibrium, it was found that the model that best fitted the experimental data was Sips for Cu2+ and Langmuir for Mn2+ in a monocomponent system. The experimental adsorptive capacity was 0.39 mmol•g-1 for Cu2+ and 0.22 mmol•g-1 for Mn2+. Regarding the bicomponent system, the antagonistic effect of the presence of Cu2+ for the adsorption of Mn2+ was verified, and the model that best described the process was the extended Langmuir process, as it indicated the highest affinity of Cu2+ with activated carbon. The results of this work demonstrate the technical potential of activated carbon prepared from corn cob for the adsorption of Cu2+ and Mn2+ ions in mono and bicomponent systems.Item Disponibilidade ambiental e risco ecológico de metais pesados em solos de diferentes posições fisiográficas de manguezal(2022-10-07) Silva, Suellayne Correia Valério da; Biondi, Caroline Miranda; Araújo, Paula Renata Muniz; http://lattes.cnpq.br/1779598476646308; http://lattes.cnpq.br/8326756664758702; http://lattes.cnpq.br/1266535065976270Mangrove soils are considered geochemical filters due to their great capacity to retain heavy metals. The level of contamination of these soils can be assessed by the environmentally available levels of heavy metals and the ecological risk. With this, the work aimed to evaluate the levels of heavy metals based on the 3051A analysis, comparing with regional and international reference levels, as well as estimating the ecological risk in areas of different physiographic positions of the Botafogo mangrove. Soil samples were collected (0-40 cm) along two transects (T1 and T2) at distances of 0, 60, 120 and 180 meters from the bank of the Botafogo River. In the field, pH and Eh were determined in sections 0 to 5, 5 to 10, 10 to 20, 20 to 30 and 30 to 40 cm of the collected soils. In the laboratory, the samples were prepared for granulometric, organic matter (MOS) and heavy metal analysis. Metal contents were determined in ICP-OES after 3051A acid digestion of soil samples. Descriptive statistics were adopted for all variables evaluated. The pH values of the evaluated areas indicated slightly acidic to neutral soils; while the values of Eh, suboxic to anoxic environments. There was a predominance of clayey soils and high levels of SOM in T1; sandy soils predominated in T2. In general, the average levels of heavy metals in T1 were higher than in T2, and exceeded regional backgrounds. Only Cr and Cu showed levels above the Threshold Effect Level (TEL), indicating possible adverse effects on the biota. The distribution of metals in the transects varied as a function of clay and SOM contents, as verified in the positive and significant correlations between metals and clay, and between metals and SOM. Ecological risk coefficients (Ei) were higher at T1 when compared to T2, but all Ei were below 40, indicating low risk. The Potential Ecological Risk (PER), considering the effect of the set of metals, was below 150, showing that the presence of metals in mangrove forests does not offer high ecological risks.Item Eucalipto e biochar para fitoatenuação da poluição do solo por cádmio(2022-10-07) Paraizo, Taciana da Silva; Freitas, Eliane Cristina Sampaio de; Silva, Fernando Bruno Vieira da; http://lattes.cnpq.br/4818569008052606; http://lattes.cnpq.br/7525975084334972; http://lattes.cnpq.br/3371289066528888Phytoattenuation is a promising technique to mitigate the deleterious effects of heavy metals toxicity, promoting an environmentally safe management of land use with crops of economic value. The use of biochars can reduce the mobility of metals and provide improvements in soil fertility, promoting safe management in polluted environments. In this sense, the present work aimed to (i) evaluate the immobilization and compartmentalization of Cd in the soil with the application of doses of a filter cake biochar (CB); (ii) assess changes in soil fertility in response to biochar application; (iii) to evaluate the growth, mineral nutrition and Cd accumulation in two eucalyptus species (Corymbia citriodora and the hybrid Eucalyptus urograndis × Eucalyptus urophylla) cultivated in a polluted soil treated with biochar; (iv) to evaluate the amelioration of the stress caused by Cd through the physiological parameters of the plants treated with biochar; and (v) evaluate the regeneration of polluted soil quality through microbiological indicators. Two experiments were carried out sequentially: the first experiment was a sorption assay. The soil was incubated with doses of biochar (0, 2, 4, 8, 12, 16, 24 and 30% m/m) for 64 days and at the end of this period, the availability and chemical fractionation of Cd in the soil were analyzed. and chemical attributes related to soil fertility; the second experiment was carried out in a greenhouse, with two species of eucalyptus grown in pots for 65 days in soil polluted by Cd, with and without the application of 5% CB. After cultivation, the growth parameters were evaluated; the levels of N, P and Cd in the tissues of the plants; chlorophyll a fluorescence parameters and photosynthetic pigments; and biomass together with soil microbial activity. From the results obtained, it was possible to infer that (i) the filter cake biochar can be indicated as a mitigating agent of soil pollution by Cd; (ii) both eucalyptus species associated with the application of 5% BT were tolerant to Cd toxicity; (iii) the cultivation of eucalyptus with the application of biochar promoted improvements in the microbiota of the soil polluted by Cd, a sensitive indicator of environmental quality; and (iv) phytotechnology using the eucalyptus species C. citriodora and the hybrid E. urograndis × E. urophylla plus the application with 5% CB showed potential to attenuate the effects of Cd in polluted areas.Item Crescimento inicial de eucalipto em solo contaminado por Cd, Pb e Zn e tratado com lodo de esgoto e biochar(2022-05-26) Ximenes, Diogo Henrique de Sá Veloso; Biondi, Caroline Miranda; Silva, William Ramos da; http://lattes.cnpq.br/5033735462082389; http://lattes.cnpq.br/8326756664758702; http://lattes.cnpq.br/3116650479929930The inadequate disposal of steel slag with high levels of heavy metals, such as lead (Pb) and cadmium (Cd), in the city of Santo Amaro, Bahia, caused the pollution of the environment and the people who live there. Today the city is known to contain the largest Pb contamination in the world. The objective of this work was to evaluate the effects of sewage sludge and its biochar in remediating the levels of Cd, Pb and Zn and the initial development of eucalyptus seedlings in the contaminated soil of the municipality of Santo Amaro. These studies aim to contribute to the determination of remediation methods and suggestion of alternative economic activities for these impacted areas. For this, an experiment was carried out in a greenhouse using a eucalyptus hybrid and application of three treatments to the soil: sewage sludge (40 t ha-1) and biochar (40 t ha-1) and a mixture of 20 t ha-1 of sewage sludge + 20 t ha-1 of biochar, in addition to the negative control (soil without addition of sludge/biochar). After the cultivation period, the available and environmentally available levels of Cd, Pb and Zn in the soil and total levels in the plants were evaluated. The application of biochar promoted better development of eucalyptus seedlings, presenting better results in the production of dry matter of the aerial part, height and diameter. Biochar + sewage sludge considerably reduced (60%) the availability of Zn in the soil, compared to the control. The use of biochar in the soil was efficient in reducing the environmentally available levels of heavy metals, immobilizing them and making them less available to the plant. Eucalyptus seedlings were more efficient in translocating Zn to the shoot in the sewage sludge treatment, showing a better index, while for Cd and Pb the seedlings were more efficient in immobilizing metals in the roots, especially Pb, which showed higher value. The results showed that biochar can be indicated as a remediation agent in the contaminated soil of Santo Amaro, since it promoted a decrease in the mobility and availability of metals in the soil. The sewage sludge can be indicated as a nutritional contribution in the cultivation of seedlings and the eucalyptus seedlings were presented as potential phytoremediation plants of the contaminated soil.Item Uso de espécies florestais na fitorremediação do solo contaminado por cádmio(2019-07-17) Veloso, Aline da Silva; Marangon, Luiz Carlos; Silva, Fernando Bruno Vieira da; http://lattes.cnpq.br/4818569008052606; http://lattes.cnpq.br/6130999923981614; http://lattes.cnpq.br/1011075155653039Cadmium (Cd) contamination of soils represents a potential risk to human and environmental health. The use of forest species as a metal phytoremediator can be an economically and ecologically sustainable choice when associated with silicate fertilization, which will alleviate metal toxicity to plants. In this sense, the study aimed to evaluate: the tolerance of two forest species (Casearia sylvestris Swartz and Machaerium aculeatum Raddi) cultivated in a soil contaminated by Cd and submitted to silicate adduction; bioaccumulation and distribution of Cd and Si, as well as changes in plant nutritional status. The experiment will be carried out in a greenhouse in a completely randomized design in a 2 x 2 factorial arrangement (two forest species: M. aculeatum and C. sylvestris; combined with 0.0 and 200.0 mg kg-1 Si). with three repetitions. The soil used in the experiment was collected at a depth of 0.0 - 0.2 m and characterized chemically and physically. The soils were weighed 9 kg for each pot. Soil contamination was induced with CdCl2.H2O above 10.0 mg kg. Subsequently, they were treated with Si as calcium silicate and then a seedling of each species was transplanted to each pot. The experiment was collected after four months of transplantation. The seedlings were collected and separated in shoots and roots; soil samples were also collected. Soils and plants were extracted and the contents of Cd and Si were determined; In the vegetal tissues the contents of N, P, K, Ca and Mg were determined. The results were submitted to descriptive statistical analysis, ANOVA (one way p <0.05) and Tukey test (p <0.05). The results showed that M. aculeatum presented better tolerance to Cd and when associated with Si obtained higher root biomass and better nutritional status, as well as Si influenced the translocation of Cd to shoot. Although Cd bioaccumulation was more significant in C. syvestris, its development was affected by biomass loss and poorer nutritional status. The distribution of Cd in both species presented the highest concentration in the root. Evaluating the best yield and biomass results, tolerance and nutritional status, M.aculeatum demonstrated potential as a phytostabilizer of cadmium contaminated soil.Item Potencial fitorremediador de Erythrina velutina Willd. cultivada em solo contaminado com cobre e incorporação de biocarvão(2022-10-04) Pundrich, Maria Gabriella Rodrigues; Freitas, Eliane Cristina Sampaio de; http://lattes.cnpq.br/7525975084334972; http://lattes.cnpq.br/2323613741603823In recent decades, researches have been demonstrating how heavy metals have the ability to stick and accumulate in the environment, being harmful to human health and the environment. Once the contamination of the soil happens, some actions are needed for the soil’s remediation.The objective of this reasearch was to evaluate the growth of the Erythrina velutina Willd seedlings cultivated in contaminated soil with copper and biochar. The first experiment was conducted for 21 days and the second for 69 days and analyzed the following morphological variables: Aerial Part Height (APH), Stem Diameter (SD), Aerial Part Increment (API) Stem Diameter Increment (SDI), Root’s Length (RL), Aerial Part Dry Mass (APDM), Root Dry mass (RDM), Total Dry Mass (TDM), Ratio between Aerial Part and Stem Diameter (AP/SD), Leaflet Numbers (LN), Leaflets Area (LA), Dickson Quality’s Index (DQI), Translocation Index (TI), Water Content in Aerial Part and Root (WCAPT) and Copper Concentrations in plant’s tissue (aerial and root part) through the EDS (energy dispersive spectroscopy).The collected data were submitted to a variance analysis (ANOVA) (p < 0,05) and Tukey test (p < 0,05). In the first experiment, it was observed that the biochar didn’t reveal any positive effect and didn’t benefit the growth of the seedlings. This result can be explained by the characteristics of biochar, influenced by the raw material and the carbonization process. In addition, the biochar could also have increased the cation exchange capacity and, consequentially, decreased Copper leach, enabling it to be more available to the seedlings. As for the second experiment, there was no significant difference of the 5% morphological variable of the seedlings, but it didn’t have Copper in the tissues analyzed, which could mean that the plant didn’t absolve as a result to a possible leach and/or an adsorption of the feedstock. Therefore, it is necessary complementary researches to evaluate the potential of Erythrina velutina Willd in projects of phytoremediation in soils contaminated by Copper.