More and more attention has been paid to the research on phytoremediation and hyperaccumulators. Arsenic (As) uptake by hyperaccumulator plant species depends on many different environmental factors. Fertilizer is one of the most important factors because the plant growth needs nutrients. In this study, the pot experiments were conducted in 12 weeks to understand the effect of different fertilizer on As removal capacity of Pityrogramma calomelanos and Pteris vittata. The results showed that, Arsenic concentration in the frond is higher than that in the root of the fern. As removal efficiency of the ferns from the soil amended with both inorganic and organic fertilizer is highest. The ferns removed As content in soil up to 7.4 and 12.6 mg As per kg DW soil, respectively. For the control experiments without adding fertilizers, As removal ability of the ferns from the soil is lowest that was only 2.1 mg As per kg DW soil. / Trên thế giới đã và đang có nhiều nghiên cứu, ứng dụng phương pháp sử dụng thực vật để xử lýônhiễm, đặc biệt là các loài thực vật siêu tích tụ kim loại nặng. Sự tích lũy Asen (As) trong các loài thực vật siêu tích lũy phụ thuộc vào rất nhiều yếu tố môi trường và dinh dưỡng khác nhau. Phân bón là một trong những yếu tố quan trọng nhất vì sự phát triển cây rất cần chất dinh dưỡng. Trong nghiên cứu này, các thí nghiệm được tiến hành trong 12 tuần để đánh giá về ảnh hưởng của các loại phân bón khác nhau đến khả năng xử lý ô nhiễm As trong đất của dương xỉ. Kết quả thu được cho thấy, nồng độ As tích lũy trong phần thân của dương xỉ cao hơn rất nhiều so với phần rễ của cây. Hiệu quả loại bỏ As ra khỏi đất của dương xỉ trong các thí nghiệm bổ sung cả phân bón vô cơ và phân bón hữu cơ là cao nhất. Pityrogramma calomelanos và Pteris vittata có thể loại bỏ hàm lượng As trong 1 kg trọng lượng khô đất tương ứng lên đến 7,4 và 12,6 mg. Các công thức thínghiệm đối chứng không bổ sung phân bón thì cho hiệu quả loại bỏ As ra khỏi đất là thấp nhất chỉ 2,1 mg As trên 1 kg trọng lượng khô đất.

Made available in DSpace on 2015-04-20T12:31:38Z (GMT). No. of bitstreams: 1 Tese Edson Valente.pdf: 791720 bytes, checksum: 2b118211a5c89a68aa642ece2e2d7af3 (MD5) Previous issue date: 2008-04-28 / Fundação de Amparo à Pesquisa do Estado do Amazonas / Heavy metals accumulate up frequently in the top layer of soil on the roots accessible principles of the plants. In advanced stages of infection may reach decimate the biota or even present concentrations thousands of times higher than in the aquatic system. This is due to changes in its chemical forms allowing the build up in living organisms. This study evaluated is the behavior of the species Senna multijuga, Caesalpinia echinata and Shizolobium amazonicum in soils contaminated by heavy metals from landfill (ASC) and Manaus Industrial Pole (PIM). The study was conducted in a greenhouse for five months. In soil, were analyzed the chemical and physical attributes and concentration of heavy metals by atomic absorption spectrometry, (FAAS) in the air-acetylene flame in fractions exchangeable, carbonate, iron/manganese oxide and organic matter. The plant, the parties were separated and air root, dried at 65 °C, digested with HNO3 and HClO4 (4:1) at 200 °C for two hours and the concentrations of heavy metals determined by FAAS. The results showed that the metals have different distributions in contaminated soil, being influenced by factors such as pH, CEC, amount of organic matter, complexation, competition ion and chemical interactions that contributed to their mobility and/or adsorption. The hierarchical analysis (HCA) and major components (PCA) revealed a similarity between the soils and with strong relationships between Cd, Co, Cr, Mn, in the soil of the ASC and Cd, Cu, Mn, Ni, Pb and Zn in the soil the PIM. The hierarchical analysis (HCA) and major components (PCA) revealed a similarity between the soils and with strong relationships between Cd, Co, Cr, Mn, in the soil of the ASC and Cd, Cu, Mn, Ni, Pb and Zn in the soil the PIM. The species multijuga Senna was the best that it was developed in contaminated soil. The Caesalpinia echinata has potential accumulator to the elements Mn and Zn. The three species can be classified as fitoextratora and hiperacumuladora for Co, Cd, Cu, Ni, Mn, Fe, Cr, Zn and Pb, regardless of the soil analyzed. / Os metais pesados se acumulam freqüentemente na camada superior do solo, ficando acessíveis as raízes das plantas. Em estágios avançado de contaminação podem chegar dizimar a biota ou, mesmo apresentar concentrações milhares de vezes maiores do que no sistema aquático. Isso ocorre devido às mudanças nas suas formas química possibilitando o acúmulo em organismos vivos. Neste trabalho avaliaram-se o comportamento das espécies Senna multijuga, Caesalpinia echinata e Shizolobium amazonicum em solos contaminados por metais pesados do aterro sanitário de Manaus (ASC) e Pólo Industrial de. Manaus (PIM). O estudo foi desenvolvido em casa de vegetação durante cinco meses. No solo, foram analisados os atributos químicos e físicos e concentração dos metais pesados por espectrometria de absorção atômica (FAAS) em chama aracetileno nas frações trocável, carbonácea, oxídica e matéria orgânica. Nas planta, foram separadas as partes aéreas e radiculares, secas a 65 oC, digeridas com HNO3 e HClO4 (4:1) a 200 oC por duas horas e as concentrações de metais pesados determinadas por FAAS. Os metais possuem distribuições diferentes nos solos contaminados, sendo influenciados por fatores como pH, capacidade de troca catiônica (CTC), quantidade de matéria orgânica, complexação, competição iônica e interações químicas que contribuíram para sua mobilidade e/ou adsorção. As análises hierárquica (HCA) e componentes principais (PCA) revelaram uma similaridade entre os solos estudados e com relações fortes entre Cd, Co, Cr e Mn, no solo do ASC e Cd, Cu, Mn, Ni, Pb e Zn no solo do PIM. A espécie Senna multijuga foi a que melhor se desenvolveu nos solos contaminados. A Caesalpinia echinata possui potencial acumulador para os elementos Mn e Zn. As três espécies podem ser classificadas como fitoextratora e hiperacumuladora para Co, Cd, Cu, Ni, Mn, Fe, Cr, Zn e Pb, independentemente dos solos analisados.

L’hypothèse selon laquelle l’accumulation des métaux lourds par les plantes a évolué comme mécanisme de défense contre les herbivores a été testée avec l’hyperaccumulatrice de zinc Thlaspi caerulescens (Brassicaceae). En utilisant l’écotype métallicole (poussant sur sols métallifères) et l’écotype non métallicole (sols normaux) de T. caerulescens, nos résultats ont conduit à rejeter l’hypothèse de défense par accumulation de métaux: les plantes ont été consommées indépendamment de leur concentration en Zn dans toutes les situations expérimentales examinées (conditions contrôlées, jardin expérimental, populations naturelles). Par contre, les herbivores ont montré une préférence systématique pour les plantes de l’écotype métallicole, quelle que soit leur concentration en Zn. Lorsque l’on mesure les concentrations en métabolites secondaires défensifs (glucosinolates) des écotypes métallicole et non métallicole de T. caerulescens, on constate que les individus d’origine métallicole produisent constitutivement moins de glucosinolates que les individus non métallicoles, tant dans les populations belges que dans les populations françaises. Par ailleurs, sur les sites métallifères où ont évolué les populations métallicoles, on constate à la fois une plus faible pression d’herbivorie sur les plantes (moins de dégâts) et une plus faible densité de gastéropodes que dans les sites normaux. La diminution des défenses chez l’écotype métallicole serait la conséquence d’un relâchement de la pression d’herbivorie sur les sites métallifères. <p>En outre, nous avons montré que la chenille spécialiste d’Issoria lathonia (Nymphalidae) est capable de se développer sur les feuilles riches en Zn de l’accumulatrice de zinc Viola calaminaria (Violaceae) en excrétant efficacement le Zn dans leurs fèces. <p> L’ensemble de nos résultats suggère donc que l’hyperaccumulation des métaux lourds n’a pas évolué en tant que mécanisme de défense contre les herbivores.<p> / Doctorat en sciences, Spécialisation biologie végétale / info:eu-repo/semantics/nonPublished

Certaines plantes, dites hyperaccumulatrices, ont la capacité de se développer sur des sols riches en métaux et d’accumuler ces métaux à des concentrations élevées. L’incinération de la biomasse produit des cendres qui contiennent de 10 à 25% en masse de Ni. Ce travail s’inscrit dans la continuité d’une recherche menée par l’équipe depuis plusieurs années, qui a donné lieu notamment à un brevet sur la production du sel double sulfate de nickel et d’ammonium hexahydraté (ANSH) à partir de la biomasse d’Alyssum murale. Le manuscrit comprend d’abord une synthèse bibliographique sur la phytomine, allant des hyperaccumulateurs aux procédés de valorisation, essentiellement centrée sur le nickel. Ensuite, ont été comparées quinze plantes hyperaccumulatrices (des genres Alyssum, Leptoplax et Bornmuellera) provenant d’Albanie ou de Grèce, en vue de leur application pour la phytomine. Les teneurs en nickel ont été mesurées dans les différents organes des plantes et dans les cendres obtenues par combustion. Les trois genres ont de l’intérêt pour l’application, les plantes contiennent 1 à 3% en masse de nickel et les cendres 15 à 20 %. Le procédé hydrométallurgique de production d’ANSH a été étudié étape par étape en vue d’optimiser chaque étape pour produire un sel très pur tout en économisant matière et énergie et minimisant la production d’effluents et de déchets. Ce travail a conduit à l’amélioration du procédé de départ. Enfin, de nouvelles pistes ont été proposées pour conduire à de nouveaux procédés et produits du nickel. Les résultats obtenus et la dynamique actuelle autour de la phytomine montrent l’intérêt de cette approche et annoncent son développement imminent / Some plants, known as hyperaccumulators, are able to develop on metal containing soils and to accumulate these metals at high concentrations in shoots. Biomass incineration leads to ash containing 10 to 25 wt % nickels, greater than in some mineral ores. This work follows a research that has been carried out by the team for several years, which has resulted in a patent on the hydrometallurgical production of the double salt ammonium and nickel hexahydrate (ANSH) from the biomass of Alyssum murale. It aims at improving the synthesis method of this salt in order to upscale it at the pilot scale and explore new methods leading to new products. The manuscript begins with a bibliographic review on phytomining from hyperaccumulators to metal recycling processes, essentially focused on nickel. Then ca 15 hyperaccumulator plants (genus Alyssum, Leptoplax and Bornmuellera) collected in Greece or Albania have been compared, in the objective of phytomining. Nickel concentrations were measured in the plant organs and in the ashes after combustion. The three types of plants are of great interest for the technology, they contain 1 to 3 wt % of nickel and the ashes 15 to 20%. The hydrometallurgical process of ANSH production was investigated step by step to optimize each step to produce a salt of high purity, to decrease materials and energy consumption and to minimize effluent and waste production. The process was thus improved. Eventually, new ideas have been tested for new processes and nickel products. The obtained results and the current dynamics prove the interest of phytomining and announce its imminent development

The biosorption of copper, nickel, gold and platinum from single metal aqueous solutions by the nickel hyperaccumulator Berkheya coddii plant biomass was investigated. Potentiometric titrations of the biomass and determination of optimal sorption pH for each metal showed that nickel ions were released from the biomass into solution. The presence of free nickel ions interfered with the uptake of the other three metals and further biosorption investigations were discontinued. Three fungal isolates found colonising metal solutions were cultured and screened for their ability to remove 50 mg.l⁻¹ of copper, nickel, gold and platinum from solution and to survive and grow in precious metal refinery wastewaters. One isolate was selected for further studies based on its superior metal uptake capabilities (35 and 39 mg.l⁻¹ of gold and platinum, respectively) and was identified as Phoma glomerata. Copper, nickel, gold and platinum uptake studies revealed that nickel and gold were the most toxic metal ions, however, toxicity was dependent on pH. At pH 6 more biomass growth was achieved than at lower pH values and metal uptake increased by 51 and 17 % for copper and nickel, respectively. In addition, the production of extracellular polymeric substances played a role in base metal interaction. Precious metals were observed to be preferentially removed from solution, complete removal of gold and platinum was observed at all initial pH values, 89 % of copper was bioaccumulated at an initial metal concentration of 55 mg.l⁻¹ (pH 6) and only 23 % of nickel was removed from solution under the same conditions. Metal bioaccumulation was confirmed through transmission electron microscopy and micro particle induced X-ray emission. The effect of P. glomerata immobilised in a packed bed reactor on precious metal refinery wastewaters was investigated. It was found that the fungal isolate was not able to remove the high salt and chemical oxygen demand concentrations found in the wastewaters, however due to its ability to survive and grow in undiluted wastewater and remove metal ions from solution it may be utilised as a metal detoxification step in the treatment process train. / PDFCreator Version 0.9.0 / AFPL Ghostscript 8.53