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Potencial da alface-d??gua (Pistia stratiotes) para descontamina??o de ?guas contaminadas por Zn e Cd / Potential of water lettuce (Pistia stratiotes) for decontamination of water contaminated by Zn and CdRODRIGUES, Ana Carolina Dornelas 23 February 2016 (has links)
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Previous issue date: 2016-02-23 / FAPERJ / Nowadays water contamination by heavy metals is an increasingly common problem, mainly due to the intensity of human activities, such as industrial, which often discard these environments their effluents enriched with these elements. In this scenario, this work was to evaluate the potential of water lettuce (Pistia stratiotes) in the decontamination of water contaminated by heavy metals zinc (Zn) and Cadmium (Cd). For that, this research was divided into three chapters. In the first chapter, it was evaluated the ability to biosorption of heavy metals by dry matter of water lettuce where laboratory adsorption isotherms were carried out with five increasing doses of Zn contamination (1.8; 18; 50; 79 and 105 mg L-1) and 4 doses of Cd (0.01, 0.1, 1 and 10 mg L-1) in nine sampling times (1, 3, 6, 12, 24, 36, 48, 60 and 72 hours). The results showed that the dry biomass of water lettuce has biosorption capacity of the metals analyzed, enhanced by increasing the contact time with the solution. This conclusion was also demonstrated by determining the isothermal linear model, which indicates a high affinity of the adsorbent for the adsorbate. Changes in the morphology of the biomass were demonstrated by scanning electron microscopy images (SEM) before and after biosorption. In the second chapter it was evaluated the potential fitoextrator of water lettuce grown in increasing doses of Zn and Cd (separately) and the physiological response of the plant to this contamination. The experiment evaluated 4 doses of contamination of each metal (Zn = 0, 1.8, 18 and 180 mg L-1 and Cd = 0, 0.1, 1 and 10 mgL-1) and cultivation time 4 (24, 48, 72 and 168 hours). In each survey were analyzed: heavy metal content in the solution, root and aerial part of the plant; content of photosynthetic pigments by direct and indirect method and photosynthetic efficiency by transient fluorescence of chlorophyll a. The results showed that water lettuce has high potential to absorb and accumulate heavy metals in their tissues, preferably in the roots, thus promoting the maintenance of the pigment synthesis and photosynthetic efficiency in most doses tested. This absorption was enhanced with increasing time of cultivation, which increased the translocation of metals to shoot and carotenoid synthesis for the protection of the photosynthetic apparatus. Higher doses of the metals had their photosynthetic efficiency decreased. In the third section it was evaluated the kinetics of absorption of heavy metals by water lettuce to it have been installed to separate Zn and Cd experiments with two different concentrations of each metal (Zn = 18 and 1.8 and 0.1 Cd and 1.0 mg L-1), with three repetitions each, totaling 12 experimental units (6 units for each element). Aliquots of the solutions and measurement of pH were carried out at certain times until stabilization of the levels of metals in the solution. At the end, the biomass production, the levels of metals and the kinetic parameters of absorption (Km and Vmax) were evaluated. The results showed that the pH of the solutions was not affected by the cultivation of water lettuce and the highest Zn and Cd absorption rates were found in larger doses contamination of the solution. Biomass production was negatively affected by contamination, but these results did not affect the rate of absorption of metals by plants. Based on all the results it can be concluded that the water lettuce has potential for remediation of water bodies contaminated by heavy metals Zn and Cd, both with its dry biomass as for its in vivo cultivation. / Atualmente a contamina??o da ?gua por metais pesados ? problema cada vez mais frequente, principalmente devido a intensidade das atividades antr?picas, como as industriais, que muitas vezes descartam nesses ambientes seus efluentes enriquecidos com esses elementos. Esse trabalho teve como objetivo avaliar o potencial da Alface-d??gua (Pistia stratiotes) na descontamina??o de ?guas contaminadas pelos metais pesados zinco (Zn) e c?dmio (Cd). A pesquisa foi dividida em 3 cap?tulos. No primeiro, foi avaliada a capacidade de biossor??o de metais pesados pela mat?ria seca da Alface-d??gua, onde foram realizadas isotermas de adsor??o em laborat?rio, com cinco doses crescentes de contamina??o por Zn (1,8; 18; 50; 79 e 105 mg L-1) e 4 doses de Cd (0,01, 0,1, 1 e 10 mg L-1) em nove tempos de coleta (1, 3, 6, 12, 24, 36, 48, 60 e 72 horas). Os resultados mostraram que a biomassa seca da Alface-d??gua possui capacidade de biossor??o dos metais analisados, potencializada pelo aumento do tempo de contato com a solu??o. Tal conclus?o tamb?m foi demonstrada pela determina??o do modelo isot?rmico linear, que indica alta afinidade do adsorvente pelo adsorbato. Altera??es na morfologia da biomassa foram observadas na microscopia eletr?nica de varredura (MEV) antes e depois da biossor??o. No segundo cap?tulo foi avaliado o potencial fitoextrator da Alface-d??gua cultivada em doses crescentes de Zn e Cd (separadamente) e as resposta fisiol?gicas da planta a essa contamina??o. O experimento avaliou 4 doses de contamina??o de cada metal (Zn = 0; 1,8; 18 e 180 mg L-1 e Cd = 0; 0,1; 1 e 10 mg L-1) e 4 tempos de cultivo (24, 48, 72 e 168 horas). Em cada coleta foram analisados: teores de metais pesados na solu??o, raiz e parte a?rea da planta; teores de pigmentos fotossint?ticos por m?todo direto e indireto e efici?ncia fotossint?tica atrav?s da fluoresc?ncia transiente da clorofila ?a?. Os resultados mostraram o elevado potencial da Alface-d??gua em absorver os metais pesados e acumular em seus tecidos, preferencialmente nas ra?zes, o que favoreceu a manuten??o da s?ntese de pigmentos e a efici?ncia fotossint?tica na maioria das doses testadas. Essa absor??o foi potencializada com o tempo de cultivo, que aumentou a transloca??o dos metais para parte a?rea e a s?ntese de carotenoides para prote??o do aparato fotossint?tico. As maiores doses dos metais tiveram sua efici?ncia fotossint?tica diminu?da. No terceiro cap?tulo foi avaliada a cin?tica de absor??o dos metais pesados pela Alface-d??gua, sendo instalados experimentos separados para Zn e Cd, com duas concentra??es diferentes de cada metal (Zn =1,8 e 18 e Cd 0,1 e 1,0 mg L-1), com 3 repeti??es cada, totalizando 12 unidades experimentais (6 por elemento). Al?quotas das solu??es e aferi??o do pH foram realizadas em tempos determinados at? a estabiliza??o dos teores dos metais na solu??o. Ao final foram avaliados a produ??o de biomassa, os teores de metais e os par?metros cin?ticos de absor??o (Km e Vmax). Os resultados mostraram que o pH das solu??es n?o foi afetado pelo cultivo da Alface-d??gua e que as maiores velocidades de absor??o de Zn e Cd foram encontradas nas maiores doses de contamina??o da solu??o. A produ??o de biomassa foi afetada negativamente pela contamina??o, por?m esses resultados n?o interferiram na velocidade de absor??o dos metais pela planta. Com base em todos os resultados pode-se concluir que a Alface-d??gua apresenta potencial para remedia??o de corpos h?dricos contaminados pelos metais pesados Zn e Cd, tanto com sua biomassa seca como pelo seu cultivo in vivo.
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Resist?ncia ao fluxo devido a vegeta??o num trecho do Rio Pitimbu, Natal-RN / Resistance to flow due to vegetation in a stretch of the river Pitimbu River, Natal-RNVitorino, Camila Farias 29 August 2017 (has links)
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Previous issue date: 2017-08-29 / A vegeta??o macr?fita possui um papel importante na manuten??o e equil?brio dos ambientes aqu?ticos em rios e lagos nas regi?es tropicais. Em cursos d??gua de pequeno porte, essas plantas proporcionam benef?cios ecol?gicos, pois atuam na sedimenta??o e reten??o de nutrientes, propiciando melhoria nas propriedades f?sico-qu?micas da ?gua. A presen?a de macr?fitas na calha fluvial alteram o comportamento da velocidade e aumentam a resist?ncia ao fluxo, com redu??o da velocidade na se??o e aumento da profundidade. Em geral, o retardamento do escoamento est? associado a fen?menos indesej?veis, tais como inunda??o de ?reas ocupadas. O objetivo deste estudo foi investigar o comportamento da resist?ncia ao fluxo provocado pela presen?a de vegeta??o macr?fita r?gida emersa da esp?cie Aninga (Montrichardia linifera) num trecho do rio Pitimbu situado na regi?o metropolitana de Natal. Para isso foram realizadas duas campanhas hidrom?tricas, realizadas em 12/04/2017 e 15/09/2017. A metodologia empregada consistiu na medi??o de vari?veis hidr?ulicas e levantamento in situ das caracter?sticas da vegeta??o no trecho e analise da intera??o fluxo-vegeta??o. A analise da vegeta??o envolveu a delimita??o de quatro quadrantes (4 m2) definidos aleatoriamente na ?rea de estudo. Nesses quadrantes foram levantadas as caracter?sticas morfol?gicas das plantas e a distribui??o espacial. A medi??o das vari?veis hidr?ulicas foi feita com a discretiza??o das se??es transversais em verticais, onde foram medidas as velocidades medias pontuais. A vaz?o e o numero de Manning obtidos nas campanhas 1 e 2 foram 0,2467 m?/s e 0,069 m-1/3s; 0,2076 m?/s e 0,078 m-1/3s respectivamente. A densidade da distrbui?ao espacial da vegeta??o era 8,12 plantas/m2. O comportamento da velocidade na se??o S1 demonstrou alta variabilidade espacial, com alguns valores acima da m?dia. Esse comportamento estava associado a presen?a de vegeta??o. Foram registradas velocidades negativas em algumas regi?es a jusante das plantas, indicando a gera??o de esteiras e fluxo reverso nestes locais. O padr?o de distribui??o espacial da vegeta??o era agregado em algumas regi?es da comunidade de plantas. A intera??o fluxo-vegeta??o foi analisada a partir de uma sequ?ncia de registros fotogr?ficos. Foi poss?vel identificar o comportamento dos fluxos atrav?s das plantas: regi?es de descolamento da camada limite, regi?es de esteira e de forma??o de v?rtices. / Macrophyte vegetation plays an important role to keep balanced aquatic environments in rivers and lakes in tropical regions. In small water courses, these plants provide ecological benefits since they act on sedimentation and nutrients retention, leading to an improvement in the water physicochemical properties. The presence of macrophytes in the river channel changes the velocity behaviour and increases the resistance to flow, causing reduction in speed and increase of depth in the section. Generally, flow retardation is associated to unwanted events, such as flooding of occupied areas. The aim of this study was to investigate the hydraulic resistance behaviour to flow caused by the presence of rigid and emersed macrophyte vegetation of the species Aninga (Montrichardia linifera) in a section into Pitimbu River located in the metropolitan region in Natal. Two hydrometric campaigns were carried out on 04/24/2017 and 09/15/2017. The methodology used included measurement of hydraulic variables, in situ survey of vegetation characteristics and analysis of the flow-vegetation interaction. Vegetation analysis involved the delimitation of three quadrants (4 m2) defined in the study area. In these quadrants, the morphological characteristics of the plants and the spatial distribution were raised. The hydraulic variables were measured with the discretization of the cross sections in verticals, where the average speeds were measured. Manning flow and number obtained in campaigns 1 and 2 were 0.2467 m?/s and 0.069 m-1/3s; 0.2076 m?/s and 0.078 m-1/3s s respectively. The density of the spatial distribution of vegetation was 8.12 plants / m2. The velocity behavior in section S1 showed high spatial variability, with some values above average. This behavior was associated with the presence of vegetation. Negative velocities were recorded in some regions downstream of the plants, indicating the generation of mats and reverse flow at these sites. The pattern of spatial distribution of vegetation was aggregated in some regions of the plant community. The flow-vegetation interaction was analyzed from a sequence of photographic records. It was possible to identify the behavior of the flows through the plants: regions of boundary layer detachment, belt regions and vortex formation.
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Estudo integrado do potencial fitorremediador da Eichhornia crassipes em ambientes naturais e sua utiliza??o para obten??o de extratos proteicosMartins, Daniel Freitas Freire 24 February 2014 (has links)
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Previous issue date: 2014-02-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This study aimed to analyze the phytoremediation potential of Eichhornia crassipes in
natural environments, optimize the extraction process of crude protein from plant tissue and,
obtain and characterize this process in order to determine its viability of use instead of the
protein sources of animal and/or human feed. For this, it has been determined in
Apodi/Mossor? river water the concentration of ammonium ions, nitrite, nitrate, calcium,
magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum,
c?dmium, lead, and total chromium; It was determined in plant tissue of aquatic macrophytes
of Eichhornia crassipes species present in Apodi/Mossor? River the moisture content, ash,
calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium,
aluminum, cadmium, lead, total chromium, total nitrogen and crude protein. It was also
determined the translocation factor and bioaccumulation of all the quantified elements; It was
developed and optimized the extraction procedure of crude protein based on the isoelectric
method and a factorial design 24 with repetition; It was extracted and characterized the extract
obtained by determining the moisture content, ash, magnesium, potassium, iron, copper,
manganese, zinc, nickel, cobalt, sodium, cadmium, total nitrogen and crude protein. And
finally, it was also characterized the protein extract using Thermogravimetric Analysis (TG),
Derived Thermogravimetric (DTG), Differential Scanning Calorimetry (DSC), Infrared
Spectroscopy (FT-IR) and jelly-like electrophoresis of polyacrylamide (SDS -PAGE) to assess
the their molecular weights/mass. Thus, from the results obtained for the translocation and
bioaccumulation factors was found that the same can be used as phytoremediation agent in
natural environments of all quantified elements. It was also found that the developed method
of extraction and protein precipitation was satisfactory for the purpose of the work, which
gave the best conditions of extraction and precipitation of proteins as: pH extraction equal to
13.0, extraction temperature equals 60 ? C, reaction time equals to 30 minutes, and pH
precipitation equals to 4.0. As for the extract obtained, the total nitrogen and crude protein
were quantified higher than those found in the plant, increasing the crude protein content
approximately 116.88% in relation to the quantified contente in the vegetal tissue of
macrophyte. The levels of nickel and cadmium were the unique that were found below the
detection limit of used the equipment. The electrophoretic analysis allowed us to observe that
the protein extract obtained is composed of low polypeptide chains by the molecular and
phytochelatins, with 6 and 15 kDa bands. Analysis of TG, DTG, DSC and FT-IR showed
similarities in protein content of the obtained extracts based on different collection points and
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parts of the plant under study, as well as commercial soy protein and casein. Finally, based on
all these findings, it was concluded that the obtained extract in this work can be used instead
of the protein sources of animal feed should, before that, test its digestibility. As human
supplementation, it is necessary to conduct more tests associated with the optimization
process in the sense of removing undesirable components and constant monitoring of the
water body and the raw material used / Este trabalho analisou o potencial fitorremediador da Eichhornia crassipes em
ambientes naturais, otimizou o processo de extra??o da prote?na bruta do tecido vegetal e
obteve e caracterizou a mesma, determinando sua viabilidade de uso em substitui??o as fontes
prot?icas de ra??es animais e/ou humana. Para isso, determinou-se na ?gua do Rio
Apodi/Mossor? a concentra??o de ?ons am?nio, nitrito, nitrato, c?lcio, magn?sio, pot?ssio,
ferro, cobre, mangan?s, zinco, n?quel, cobalto, s?dio, alum?nio, c?dmio, chumbo e cromo
total; Determinou-se no tecido vegetal das macr?fitas aqu?ticas da esp?cie Eichhornia
crassipes presentes no Rio Apodi/Mossor? o teor de umidade, cinzas, nitrog?nio total e
prote?na bruta e os mesmos metais determinados na ?gua. Calculou-se o fator de transloca??o
e bioacumula??o de todos os elementos quantificados; Desenvolveu-se e otimizou-se o
procedimento de extra??o da prote?na bruta utilizando como base o m?todo isoel?trico e um
planejamento fatorial 24 com repeti??o; Extraiu-se e caracterizou-se o extrato obtido atrav?s
da determina??o o teor de umidade, cinzas, nitrog?nio total e prote?na bruta e os mesmos
metais determinados na ?gua. E, por fim, caracterizou-se tamb?m o extrato proteico utilizando
An?lise Termogravim?trica (TG), Termogravimetria derivada (DTG), Calorimetria
Explorat?ria Diferencial (DSC), Espectroscopia de Infravermelho (FT-IR) e Eletroforese em
gel de poliacrilamida (SDS-PAGE) para avaliar as suas massas molares. Desta forma, a partir
dos resultados obtidos para os fatores de transloca??o e bioacumula??o constatou-se que a
mesma pode ser utilizada como agente fitorremediador em ambientes naturais de todos os
elementos quantificados. Constatou-se ainda que o m?todo desenvolvido de extra??o e
precipita??o de prote?nas foi satisfat?rio para o objetivo do trabalho, onde obteve-se as
melhores condi??es de extra??o e precipita??o das prote?nas como sendo: pH de extra??o
igual a 13,0; temperatura de extra??o igual a 60?C; tempo de rea??o igual a 30 minutos; e pH
de precipita??o igual a 4,0. Quanto ao extrato obtido, os teores de nitrog?nio total e prote?na
bruta quantificados foram superiores aos encontrados na planta, chegando a aumentar o teor
de prote?na bruta cerca de 116,88% em rela??o ao teor quantificado no tecido vegetal da
macr?fita. Os teores de n?quel e o c?dmio foram os ?nicos que se apresentaram abaixo do
limite de detec??o do equipamento utilizado. A an?lise eletrofor?tica permitiu observar que o
extrato proteico obtido ? constitu?do de cadeias polipept?dicas de baixo peso molecular e
fitoquelatinas, com bandas de 6 e 15 kDa. As an?lises de TG, DTG, DSC e FT-IR permitiram
constatar semelhan?as existentes no conte?do proteico dos extratos obtidos a partir de
diferentes pontos de coleta e partes da planta em estudo, bem como da prote?na de soja
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comercial e da case?na. Por fim, com base em todas essas constata??es, conclui-se que o
extrato obtido no presente trabalho pode ser utilizado em substitui??o ?s fontes proteicas de
ra??es animais devendo, antes disso, ser testado a sua digestibilidade. Quanto a
suplementa??o humana, ? preciso a realiza??o de mais testes associados a otimiza??o do
processo no sentido de remo??o dos componentes indesej?veis e constante monitoramento do
corpo h?drico e da mat?ria-prima utilizada
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