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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Comportamento de B, Zn, Cu, Mn e Pb em solo contaminado sob cultivo de plantas e adição de fontes de matéria orgânica como amenizantes do efeito tóxico / Behavior of B, Zn, Cu, Mn e Pb in contaminated soil under plant cultivation and organic matter addition for metal toxicity amelioration

Gláucia Cecília Gabrielli dos Santos 10 November 2005 (has links)
Foram conduzidos dois experimentos em casa-de-vegetação com solo contaminado acidentalmente com metais pesados. No primeiro deles objetivou-se avaliar o potencial das espécies vegetais Brassica juncea, Raphunus sativus L., Hybiscus cannabinus e Amaranthus crentus em absorver, translocar e acumular zinco, cobre, manganês, chumbo e boro na parte aérea e assim atuarem na recuperação do solo estudado. No segundo experimento avaliou-se a aplicação dos materiais orgânicos: Solomax, turfa e concentrado húmico mineral como amenizantes de toxidez dos elementos citados para Brassica juncea. Em um terceiro experimento em laboratório, avaliou-se a capacidade de retenção de zinco pelos materiais orgânicos estudados. As variáveis avaliadas foram: produção de material vegetal; quantidades absorvida e acumulada de Zn, Cu, Mn, Pb e B; índices de translocação e remoção desses elementos pelas plantas. No solo foram determinados os teores total e disponível (DTPA e CaCl2 0,01 mol L-1) de Zn, Cu, Mn e Pb. No extrato de saturação foram determinados os teores solúvel (ICP-OES) e livre (eletroforese capilar) dos elementos citados, que também foram determinados na parte aérea da Brassica juncea. Resultados das determinações analíticas também foram introduzidos no programa de especiação iônica MINTEQ. Foram avaliados ainda os efeitos dos materiais orgânicos na distribuição dos metais pesados nas frações do solo. No ajuste dos dados do experimento de retenção de zinco foi a empregado o modelo de Freundlich e calculado o coeficiente de distribuição Kd. Embora as espécies tenham sido capazes de acumular quantidades elevadas dos elementos na parte aérea, elas não puderam ser consideradas hiperacumuladoras. O Amaranthus crentus e a Brassica juncea apresentaram os maiores índices de remoção para Zn, Mn e B. Os materiais orgânicos apresentaram valores elevados de Kd refletindo a alta afinidade do zinco pela fase sólida e elevada capacidade dos materiais orgânicos em imobilizar o elemento. Os elevados coeficientes de correlação obtidos para as isotermas de adsorção indicam que o modelo Freundlich pode ser utilizado para descrever a adsorção do Zn pelos materiais. A quantidade de Zn removida pelos materiais, em termos percentuais variou com o material e com o pH, sendo favorecida nos valores mais elevados. A turfa e o concentrado húmico reduziram os teores de metais extraídos por DTPA e CaCl2 sendo esta redução refletida nos teores acumulados pela Brassica juncea, contudo esta redução não foi suficiente para impedir os efeitos fitotóxicos dos elementos. A especiação dos metais mostrou que o Zn e o Mn encontraram-se principalmente na forma livre, enquanto que o Cu e o Pb apresentaram-se complexados à matéria orgânica dissolvida. Não foram observadas correlações significativas entre os teores dos metais determinados diretamente por eletroforese capilar e indiretamente pelo programa de especiação. O fracionamento seqüencial dos metais indicou que grande parte dos metais está ligada a frações pouco disponíveis do solo. Conclui-se que a aplicação da turfa e do concentrado húmico mineral juntamente com o cultivo do Amaranthus crentus e da Brassica juncea podem auxiliar na recuperação a longo prazo de solos contaminados com Zn, Mn Pb e B. / Two pot trials were carried out using a heavy metal accidentally contaminated soil. In the first one it was evaluated the plant absorbing, translocating and accumulating power for zinc, copper, manganese, lead and boron by the following vegetal species: Brassica juncea, Raphunus sativus L., Hybiscus cannabinus and Amaranthus crentus, so they could help in the rehabilitation of the studied soil. In the second pot trial it was evaluated the application of the following organic materials: Solomax, peat, and humic mineral concentrate for heavy metal toxicity amelioration for Brassica juncea. In a laboratory experiment it was evaluated the zinc retention capacity for the above mentioned organic materials. The measured variables were plant dry matter yield, absorbed and accumulated amounts of Zn, Cu, Mn, Pb and B; the translocation index and the removal index of metal by the mentioned plant species. The total and available (DTPA and CaCl2 001 mol L-1) content of Zn, Cu, Mn and Pb, were determined in soil samples. Concerning the soil saturation extract, the soluble and free forms of the mentioned elements were determined by ICPOES and capillary electrophoresis respectively. The same metals were also determined in the plant tissue of Brassica juncea. Analytical results were introduced in the chemical equilibrium program MINTEQ in order to calculate the concentration of the free forms of Zn, Cu, Mn, and Pb. A fractioning scheme for metals in soil was carried out in order to evaluate the effect of adding sources of organic carbon. The Freundlich model was used to account for zinc adsorption by the studied organic materials and the distribution coefficient Kd was also calculated. Although the plant species were able to accumulate high amounts of metal in the aerial part, that could not be considered as a hipper-accumulation process. The highest metal removal indexes were observed for Brassica juncea and Amaranthus crentus. Organic materials showed high values of Kd, reflecting its high affinity for zinc and a great capacity of zinc immobilization as well. Freundlich model was very effective in describing the adsorption isotherms as indicated by the high determination coefficients. Zinc retention was affected by the organic material type and pH, being favored by the highest studied pH values. Peat and humic mineral concentrate reduced the amounts of metals extracted by DTPA and CaCl2 in soil but the reduction was not great enough to avoid toxic effects in plants. Zn and Mn were present mostly as free cations in soil saturation extract while Pb and Cu were complexed by dissolved organic matter. It was not detected any significant correlation between free metal contents directly determined by capillary electrophoresis and those estimated by MINTEQ. Metal sequential extraction showed that most of them occurred in the least available fractions of soil. Peat and humic mineral concentrate application to soil associated with Amaranthus crentus and Brassica juncea cultivation may be used in long term amelioration of soils contaminated with Zn, Mn, Pb and B.
52

Cobalt and Nickel Bioavailability for Biogas Formation

Gustavsson, Jenny January 2012 (has links)
Supplementation of trace metals such as Co and Ni may improve anaerobic digestion of organic material for biogas formation. Which trace metals that are needed and the quantity to apply are, at least partly, related to metal speciation and bioavailability. According to the common perception, metals have to be dissolved to be available for microbial uptake. However, the impact of trace metal speciation on bioavailability is still unclear. The purpose of the present study was to investigate the effect of Fe-, Co- and Ni-addition on the biogas process performance of stillage-fed lab-scale biogas tank reactors. Metal speciation was determined by sequential extraction (SE), extraction of acid volatile sulfides (AVS) and continuously extracted metals (AVS-Me). Sulfur forms, which may be associated to metal speciation, were studied with S XANES (sulfur X-ray absorption near edge structure). The effect of different Co- and Ni-concentrations on process microflora composition was examined with quantitative PCR (qPCR) and 454-pyrosequencing. The results showed that Co- and Ni-supplementation stimulated and stabilized the biogas process performance by increasing methane production and substrate utilization and by establishing low concentrations of volatile fatty acids. 10-20% of the total Co-amount was found in the dissolved phase, which shows that Co was relatively available for microbial uptake. Nickel was entirely associated to organic matter/sulfides and AVS, and was therefore considered to be non-bioavailable. Nevertheless, Ni-supplementation had stimulatory effects on the biogas process performance. This implies that Ni was available for microbial uptake despite its extensive association to sulfides and that other mechanisms than solubility govern the availability of this trace metal. The microbial analyzes revealed that it was primarily the methane producers which were affected by the concentration of Co and Ni. At stimulatory Co- and Ni-concentrations, the archaeal methanogenic community was dominated by aceticlastic Methanosarcinales. At lower Co- or Ni-levels, when biogas process performance was poor, an increase in hydrogenotrophic Methanomicrobiales was observed. This indicates a shift in the methanogenic flora, from being dominated by acetate utilizers to increased importance of hydrogen utilizers, and that the former was more dependent on Co and Ni. / Tillsats av spårmetaller kan förbättra rötning av organiskt material till biogas. Typ och mängd av respektive spårmetall som behöver tillsättas för att uppnå stimulerande effekter, varierar mellan processer. Detta är delvis kopplat till specieringen och biotillgängligheten av metallerna. Endast fria metalljoner och vissa metallkomplex antas vara tillgängliga för mikrobiellt upptag. Det är dock i många fall oklart hur metallernas speciering påverkar biotillgängligheten. Syftet med föreliggande studie var därför att undersöka effekten av tillsats av Fe, Co och Ni för biogasproduktion från drank, en restprodukt i produktion av bioetanol från spannmål, samt att undersöka hur dessa metallers speciering påverkar deras biotillgänglighet. Effekten av tillsatserna av Fe, Co och Ni undersöktes på biogasreaktorer i lab-skala. Metallernas speciering bestämdes genom sekventiell extraktion (SE), extraktion av AVS (acid volatile sulfide) och kontinuerligt extraherade metaller (AVS-Me). Svavelformer med betydelse för metallspeciering studerades med S XANES (sulfur X-ray absorption near edge structure). Effekten av olika Co- och Ni-koncentrationer på processens mikroflora undersöktes molekylärbiologiskt med kvantitativ PCR (qPCR) och 454-pyrosekvensering. Resultaten visade att Co och Ni stimulerade och stabiliserade biogasprocessen genom ökad metanproduktion, ökad utrötningsgrad samt låga halter av flyktiga fettsyror i det studerade systemet. 10-20% av totala mängden Co återfanns i löst fas, vilket visar att Co var relativt lättillgängligt för mikroorganismerna. Nickel var däremot enbart bundet till organiskt material/sulfider och AVS och kunde alltså betraktas som otillgängligt. Trots detta hade även tillsatsen av Ni stimulerande effekter på biogasprocessen. Det innebär att mikroorganismerna har förmåga att komma åt Ni bundet i svårlösliga sulfidföreningar och att andra mekanismer än löslighet reglerar tillgängligheten av denna spårmetall. De molekylärbiologiska analyserna visade att framför allt de metanbildande mikroorganismerna påverkades av halten av Co och Ni. De halter, som gav välfungerande processer, dominerades helt av acetiklastiska Methanosarcinales. Vid lägre halter av Co eller Ni, då processerna gick sämre, tillkom vätgasutnyttjande metanogener. Det tyder på ett skift i bildningen av metan från att ha dominerats av acetatklyvning till att vätgasutnyttjarna fått större betydelse och att de förra är mer beroende av Co och Ni.
53

Long-term metal retention processes in a peat bog : Field studies, data and modelling

Syrovetnik, Kristina January 2005 (has links)
The study was inspired by the need to assess long-term metal retention in municipal solid waste (MSW) landfills. The long-term processes in landfills are poorly known due to the relatively short time that such landfills have been in existence. Natural analogues where similar metal binding processes could be expected were therefore sought for. The work described in this thesis aims to elucidate the long-term transport and attenuation processes involved in the retention of heavy metals in a peat bog, through field studies and modelling. The Oostriku peat bog (central Estonia) has been exposed to metal-rich groundwater discharge over a long period of time and was found to have accumulated high concentrations of Fe, other heavy metals (e.g. Pb, Cu, Zn, Mn), and As. It was characterised in detail with respect to metal depth distribution and main metal binding mechanisms (using an optimised Tessier extraction scheme). The oxidation of metal sulphides in the surrounding carbonate bedrock was proposed to be a possible long-term source of heavy metals in the water emerging in a spring at the peat site. The water in the spring and peat pore-water was sampled and analysed. The dissolution sequence of the sulphide minerals and evolution of the water composition along a flowpath in the carbonate rock were modelled. Resulting aqueous phase concentration of major and minor elements are discussed in relation to governing geochemical processes. The simulated water composition was compared with that observed. Retention of metals transported with water through the peat was assessed through modelling equilibrium sorption on solid organic matter and amorphous ferric oxyhydroxide by using a simplified quantitative modelling approach and independently obtained data. Dynamic evolution of metal sorption fronts along a peat profile over time was modelled to test metal-metal competition effects. A possible formation of ferric oxyhydroxide in the peat bog was also assessed with the model. / QC 20101001
54

Γεωχημική μελέτη σε επιφανειακά ιζήματα του επιβατικού τμήματος του Λιμένα Πειραιώς

Αρβανίτης, Λεωνίδας 01 October 2008 (has links)
Το λιμάνι του Πειραιά είναι το πιο σημαντικό της Ελλάδας και ένα από τα σπουδαιότερα της Μεσογείου. Στην ευρύτερη περιοχή του λιμανιού λαμβάνουν χώρα ένα πλήθος από δραστηριότητες που επιβαρύνουν σημαντικά το λιμάνι σε βαρέα μέταλλα. Σκοπός της εργασίας αυτής είναι ο προσδιορισμός βαρέων μετάλλων σε επιφανειακά ιζήματα από το επιβατικό τμήμα του λιμανιού του Πειραιά. Στην αρχή γίνεται μια εισαγωγή για τα βαρέα μέταλλα και το ρόλο τους στα θαλάσσια ιζήματα. Ακολουθεί βιβλιογραφική ανασκόπηση που σχετίζεται με την παρουσία βαρέων μετάλλων σε θαλάσσια ιζήματα που έχουν συλλεχθεί από διάφορα λιμάνια με ποικίλες δραστηριότητες ανά τον κόσμο. Μετά από κάποια γενικά στοιχεία για το λιμάνι του Πειραιά, αναφέρονται στοιχεία της γεωλογίας της περιοχής μελέτης. Στην συνέχεια ακολουθεί περιγραφή των εργασιών πεδίου και γίνεται εκτενής αναφορά στην μεθοδολογία των χημικών αναλύσεων που εφαρμόστηκαν. Στους πυρήνες που συλλέχθηκαν έγιναν κοκκομετρικές αναλύσεις, προσδιορισμός οργανικού άνθρακα και προσδιορισμός συγκεντρώσεων βαρέων μετάλλων. Χρησιμοποιήθηκε η ολική διάσπαση (HF - HNO3 - HClO4) για τον προσδιορισμό των ολικών συγκεντρώσεων των μετάλλων και επίσης χρησιμοποιήθηκε η διαδοχική εκχύλιση για τον προσδιορισμό της χημικής κατανομής των μετάλλων στις διάφορες φάσεις των ιζημάτων και για την αποτίμηση της κινητικότητας τους. Τα αποτελέσματα των παραπάνω αναλύσεων έδειξαν την αρκετά σημαντική επιβάρυνση του λιμανιού σε βαρέα μέταλλα και προσδιόρισαν την κινητικότητα συγκεκριμένων μετάλλων. / The Port of Piraeus is the most important port in Greece as well as one of the important ports around the Mediterranean Sea. A lot of activities (commercial, industrial et.c) load the given port with a huge variety of heavy metals. The aim of this study is to determine the heavy metals in surface sediments from the passenger part of Port of Piraeus. At the beginning of the study there is an introduction of heavy metals and their role in marine sediments. A bibliographical review follows which is relevant to the presence of heavy metals found in marine sediments which have been collected from several ports around the world with various activities. Some data about the port is given, and then, takes place references for the geology of study area. Then, a description of field works and a detailed report of the methodology used for chemicals analysis follow. In the cores that were sampled, have been applied, grain size distribution and concentrations of heavy metals and organic carbon. In order to determine the total metal concentrations, the total digestion (HF-HNO3-HClO4) was used, and the sequential extraction procedure (BCR-SEP) was used for the determination of chemical speciation of metals. The results showed the enormous encumberment of port by heavy metals and determined the mobility of various metals.
55

Öljyllä ja raskasmetalleilla pilaantuneita maita koskevan ympäristölainsäädännön ja lupamenettelyn edistäminen kemiallisella tutkimuksella

Kaakinen, J. (Juhani) 05 April 2016 (has links)
Abstract Industrial emissions and soil pollution caused by harmful substances attracted an increased public awareness in the 1970s. Ministry of the Environment contributed to the rapid development of environmental legislation. Development of Finnish environmental legislation has also been significantly affected by the membership of the EU has been in 1995. Finnish legislation is largely based on EU legislation, but in some cases it includes even stricter standards and limits than those applied on the EU level. Studies of contaminated soils in Finland began with mapping of landfills in the 1980s. The clearing and renovation project of contaminated soils named SAMASE started in 1988, and approximately 10,400 contaminated areas were surveyed. Currently, the total number of objects has already expanded to about 25,000. This thesis consists of five scientific publications related to contaminated sites. Its summary deals with environmental legislation, treatment methods for soils contaminated with oils and heavy metals, and risk assessment in general. The scientific publications focus on the utilization of two chemical methods, i.e. oil biodegradation of contaminated soil studied, especially by manometric respirometric BOD Oxitop method, and the study of railway ballast using five-step sequential extraction method. The results show that the biodegradability of oil is strongly dependent on the soil matrix and the studied oils (motor and light fuel oils), which are biodegradable well under suitable conditions. When a 6-month long biodegradation study of light fuel contamination in mineral-rich soil without soil conditioning was performed, the final biodegradation degree was surprisingly almost complete (> 90 %), in contrary to the general assumption. Thus, the inherent biodegradability is a cost-efficient and a recommended treatment method for oil contaminated soils, especially in sparsely populated areas. Research of the railway ballast showed that the multi-step sequential extraction will provide valuable information about the effects of environmental circumstances on metals bioavailability or solubility for the purposes of risk assessment. This information is necessary to understand the actual environmental risks of metals in different natural environments, thus contributing to the development of licensing procedure. The results of this thesis also show that licensing related to the restoration of contaminated soils r (authority and control procedures) must be simplified. The authorities should also have sufficient chemical knowledge, since after all, environmental problems are mainly of chemical nature. / Tiivistelmä Huoli ympäristöstä nosti 1970-luvun alussa erilaiset päästöt päivänvaloon, ja haitallisten aineiden aiheuttama maaperän pilaantuminen nousi esille 1980-luvulla. Suomeen vuonna 1983 perustettu ympäristöministeriö on edesauttanut nopeaa ympäristölainsäädännön kehittymistä. Kehitykseen on vaikuttanut merkittävästi myös EU-jäsenyytemme vuodesta 1995 lähtien ja jäsenyyden myötä implementoitu EY:n lainsäädäntö. Joiltain osin säädöksemme ovat jopa tiukempia kuin EU:n vastaavat säännökset. Suomessa pilaantuneiden maiden selvitystyö alkoi kaatopaikkojen kartoituksella 1980-luvulla. Valtioneuvoston v. 1988 antaman selonteon pohjalta käynnistyi saastuneiden maa-alueiden selvitys- ja kunnostusprojekti (SAMASE), jossa kartoitettiin noin 10 400 pilaantuneeksi epäiltyä tai todettua aluetta. Tätä työtä jatketaan edelleen viranomaisten tavanomaisen lupa- ja valvontatyön ohessa. Tällä hetkellä kohteiden kokonaismäärä on noin 25 000. Tämä pilaantuneisiin maihin (PIMA) liittyvä väitöskirjatutkimus koostuu yhteenveto-osasta, jossa käsitellään alan lainsäädäntöä, käsittelymenetelmiä ja riskinarviointia yleisesti sekä viidestä osajulkaisusta, jotka keskittyvät öljyllä pilaantuneiden maiden biohajoavuuteen manometrista respirometrista BOD Oxitop -menetelmää käyttäen ja kaivosteollisuuden sivukiven (raidesepeli) raskasmetallien analytiikkaan sekventiaalista uuttoa hyödyntäen. Tutkimuksen tulokset osoittavat, että öljy biohajoaa maassa sopivissa olosuhteissa hyvin ja luontainen biohajoavuus on täten yksi käyttökelpoinen öljyllä pilaantuneiden maiden puhdistusmenetelmä. Raidesepelitutkimukset osoittivat, että monivaiheinen sekventiaalinen uutto tuo uutta arvokasta tietoa olosuhteiden vaikutuksista metallien biosaatavuudesta/liukoisuudesta niiden riskinarviointia varten. Tämä tieto on välttämätöntä, kun halutaan ymmärtää metallien todelliset ympäristövaikutukset erilaisissa luonnonolosuhteissa ja näin edistää osaltaan lupamenettelyn kehittämistä. Väitöskirjassa todetaan myös, että pilaantuneen maan kunnostuksiin liittyen viranomaisten lupa- ja valvontamenettelyä tulee yksinkertaistaa ja viranomaisilla tulisi olla riittävästi kemian tietämystä ja kemiallista ajattelua, ovathan ympäristöongelmat pääosin luonteeltaan kemiallisia.
56

Zinco, cádmio e chumbo em plantas de milho e em latossolo tratado com lodo de esgoto por nove anos consecutivos

Nogueira, Thiago Assis Rodrigues [UNESP] 22 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-22Bitstream added on 2014-06-13T19:50:04Z : No. of bitstreams: 1 nogueira_tar_me_jabo.pdf: 729453 bytes, checksum: 4d1831f28f2a39565054dec118348f0e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As maiores limitações para o uso do lodo de esgoto em áreas agrícolas são os riscos de contaminação do solo com metais pesados e sua possível transferência para a cadeia alimentar. Objetivou-se com este estudo avaliar métodos de extração e frações de Zn, Cd e Pb no solo, o acúmulo destes elementos em plantas de milho cultivadas Latossolo Vermelho eutroférrico no nono ano de aplicação de lodo de esgoto e seus efeitos na produção de matéria seca e na produtividade das plantas. O experimento foi instalado em condições de campo na FCAV/UNESP, Campus de Jaboticabal-SP, em delineamento experimental em blocos casualizados com quatro tratamentos e cinco repetições. Os tratamentos foram: 0,0 (testemunha - fertilização mineral); 45,0; 90,0 e 127,5 t ha-1 de lodo de esgoto, base seca, acumuladas em nove aplicações anuais. As concentrações médias de Cd no solo não variaram em função das doses de lodo e das metodologias estudadas. De forma contrária, as concentrações médias de Zn e Pb no solo, obtidas pela digestão com HClO4 + HF, foram 62,3 e 31,8%, respectivamente, superiores àquelas encontradas pelo ataque com HNO3 + H2O2 + HCl. Porém, quando se avaliou apenas o efeito das doses de lodo, em ambos os métodos de extração, verificou-se diferença entre os tratamentos apenas em relação à concentração de Zn no solo. Os estudos de fracionamento da matéria orgânica e da extração seqüencial de Zn, Cd e Pb indicaram que a maior parte dos metais encontrava-se nas frações com ligações mais estáveis, fração humina (matéria orgânica) e residual (extração seqüencial). Exceto para o Cd, que não foi detectado, os acúmulos de Zn e Pb nas partes das plantas de milho aumentaram com as aplicações de lodo de esgoto. Os teores de metais pesados nos grãos, quando detectados, permaneceram dentro da faixa considerada aceitável para o consumo humano... / Major limitation for using sewage sludge in agriculture is the risk of contaminating the soil with heavy metals and their possible transference the man food chain. The objective of this study was to evaluate the soil content of Zn, Cd and Pb using two methods of extraction (HNO3 + H2O2 + HCl and HClO4 + HF), in parts of maize plants grown in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years, and the effects on dry matter and grain production. The experiment was carried out under field conditions in the Experimental Farm of UNESP in Jaboticabal, São Paulo, Brazil using a randomized blocks design with four treatments and five replications. The treatments were 0.0 (control – mineral fertilization), 45.0, 90.0 and 127.5 t ha-1 sewage sludge (dry basis) accumulated during nine years. The mean concentrations of Cd in soil were not affected by the rates of sewage sludge and methods. In contrary, the mean concentrations of Zn and Pb in soil extracted by HClO4 + HF were 62.3 and 31.8%, higher than those obtained by HNO3 + H2O2 + HCl respectively. However, when the effect of sewage sludge rates was evaluated, it was verified that only soil Zn concentration was affected by the treatments. The distribution of Zn, Cd and Pb in the soil fractions was strongly associated to the humin fraction (organic matter) and residual fraction (sequential extraction). Except for Cd, that was not detected, the accumulated contents of Zn and Pb in the parts of maize plants were generally affected by the successive applications of sewage sludge to the soil. Grain contents of heavy metals, if detected, were in the interval considered acceptable for human consumption. Sewage sludge and mineral fertilization applied to soil for a long time caused similar effects on dry matter and grain production.
57

Zinco, cádmio e chumbo em plantas de milho e em latossolo tratado com lodo de esgoto por nove anos consecutivos /

Nogueira, Thiago Assis Rodrigues. January 2008 (has links)
Orientador: Wanderley José de Melo / Banca: Marcos Omir Marques / Banca: Cassio Hamilton Abreu Junior / Resumo: As maiores limitações para o uso do lodo de esgoto em áreas agrícolas são os riscos de contaminação do solo com metais pesados e sua possível transferência para a cadeia alimentar. Objetivou-se com este estudo avaliar métodos de extração e frações de Zn, Cd e Pb no solo, o acúmulo destes elementos em plantas de milho cultivadas Latossolo Vermelho eutroférrico no nono ano de aplicação de lodo de esgoto e seus efeitos na produção de matéria seca e na produtividade das plantas. O experimento foi instalado em condições de campo na FCAV/UNESP, Campus de Jaboticabal-SP, em delineamento experimental em blocos casualizados com quatro tratamentos e cinco repetições. Os tratamentos foram: 0,0 (testemunha - fertilização mineral); 45,0; 90,0 e 127,5 t ha-1 de lodo de esgoto, base seca, acumuladas em nove aplicações anuais. As concentrações médias de Cd no solo não variaram em função das doses de lodo e das metodologias estudadas. De forma contrária, as concentrações médias de Zn e Pb no solo, obtidas pela digestão com HClO4 + HF, foram 62,3 e 31,8%, respectivamente, superiores àquelas encontradas pelo ataque com HNO3 + H2O2 + HCl. Porém, quando se avaliou apenas o efeito das doses de lodo, em ambos os métodos de extração, verificou-se diferença entre os tratamentos apenas em relação à concentração de Zn no solo. Os estudos de fracionamento da matéria orgânica e da extração seqüencial de Zn, Cd e Pb indicaram que a maior parte dos metais encontrava-se nas frações com ligações mais estáveis, fração humina (matéria orgânica) e residual (extração seqüencial). Exceto para o Cd, que não foi detectado, os acúmulos de Zn e Pb nas partes das plantas de milho aumentaram com as aplicações de lodo de esgoto. Os teores de metais pesados nos grãos, quando detectados, permaneceram dentro da faixa considerada aceitável para o consumo humano ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Major limitation for using sewage sludge in agriculture is the risk of contaminating the soil with heavy metals and their possible transference the man food chain. The objective of this study was to evaluate the soil content of Zn, Cd and Pb using two methods of extraction (HNO3 + H2O2 + HCl and HClO4 + HF), in parts of maize plants grown in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years, and the effects on dry matter and grain production. The experiment was carried out under field conditions in the Experimental Farm of UNESP in Jaboticabal, São Paulo, Brazil using a randomized blocks design with four treatments and five replications. The treatments were 0.0 (control - mineral fertilization), 45.0, 90.0 and 127.5 t ha-1 sewage sludge (dry basis) accumulated during nine years. The mean concentrations of Cd in soil were not affected by the rates of sewage sludge and methods. In contrary, the mean concentrations of Zn and Pb in soil extracted by HClO4 + HF were 62.3 and 31.8%, higher than those obtained by HNO3 + H2O2 + HCl respectively. However, when the effect of sewage sludge rates was evaluated, it was verified that only soil Zn concentration was affected by the treatments. The distribution of Zn, Cd and Pb in the soil fractions was strongly associated to the humin fraction (organic matter) and residual fraction (sequential extraction). Except for Cd, that was not detected, the accumulated contents of Zn and Pb in the parts of maize plants were generally affected by the successive applications of sewage sludge to the soil. Grain contents of heavy metals, if detected, were in the interval considered acceptable for human consumption. Sewage sludge and mineral fertilization applied to soil for a long time caused similar effects on dry matter and grain production. / Mestre
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Estudo da mobilidade e da biodisponibilidade do arsênio em solos e sedimentos de Paracatu-MG

Ferreira, Marcos Manoel 29 April 2016 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2016-04-29T16:38:13Z No. of bitstreams: 1 TESE Marcos Ferreira Final.pdf: 14202319 bytes, checksum: 0a3e4b766ed3761f565f902e1f0d9730 (MD5) / Made available in DSpace on 2016-04-29T16:38:13Z (GMT). No. of bitstreams: 1 TESE Marcos Ferreira Final.pdf: 14202319 bytes, checksum: 0a3e4b766ed3761f565f902e1f0d9730 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ / Este estudo buscou avaliar a contaminação, a mobilidade e a bioacessibilidade do As na água subterrânea e em solos e sedimentos superficiais, em uma área de mineração de ouro no município de Paracatu-MG. O As apresentou valores abaixo do limite estabelecido pela legislação brasileira (< 10 g.L-1) em todas as amostras de águas subterrâneas. As avaliações realizadas indicam que as condições físicoquímicas encontradas, juntamente com as características geológicas da região são fatores preponderantes para estes baixos teores. Nas amostras de solos e sedimentos, a concentração de As total variou de 32,9 a 1280 g.g-1 e de não detectável a 4727 g.g-1, respectivamente. Os maiores teores de As nos sedimentos e solos foram encontrados na bacia do córrego Rico, mostrando a influência direta dos processos oriundos da área de mineração em sua nascente. As demais áreas apresentaram teores inferiores a esta área, mas acima da média mundial e do folhelho médio, podendo estar sob a influência de alguns processos, tais como, a ciclagem biogeoquímica natural deste elemento, deposição de sedimentos por erosão hídrica, descarga de águas subterrâneas, e dispersão atmosférica de material particulado enriquecido em As, oriundo da área de mineração. Todos estes processos proporcionam em maior ou menor proporção o enriquecimento de As na região. De acordo com os ensaios de extração sequencial utilizados, em todas as amostras de solos e sedimentos, as frações solúvel e trocável exibiram valores extremamente baixos, correspondendo a menos de 2 % do teor total de As contido nestas amostras, mostrando baixa disponibilidade do As para o ambiente nos solos e sedimentos em Paracatu. A mobilidade do As trocável nos solos de Paracatu foi avaliada através de experimentos de lixiviação em coluna. Os resultados mostraram uma associação do As com os óxidos e hidróxidos de Fe que favorecem a retenção deste metaloide nos solos mesmo na fração trocável. Segundo os resultados deste e de outros estudos, a adição de Ca a solos contaminados favorece o processo de retenção do As, mostrando grande potencial na utilização de compostos deste elemento em estratégias que visem a remediação de áreas contaminadas. / This study aims to evaluate the mobility and inaccessibility of As in groundwater and in surface soils and sediments in a mining area of gold in the Paracatu municipality- MG. The Arsenic concentrations in all the groundwater samples showed below the established limits by the Brazilian legislation (< 10 μg.L-1). The evaluations were indicating that the physical-chemical conditions encountered together with the geological characteristics of the region are predominant factors responsible to these lower values. In the soil and sediment samples, the concentration of As varied from 32,9 to 1280 μg.g-1 and to below detection limit to 4727 μg.g-1 respectively. The higher values of As in the sediments and soils were found in the Rico stream, showing the direct influence of the processes coming from its source of the mining area. The other areas showed inferior values to this area, but above world average and of the shale values, which may be under the influence of some processes, such as the natural biogeochemical cycling of this element, deposition of sediment by hydrological erosion, groundwater discharge and atmospheric dispersion of particulate material originated by mining. All these processes provide in proportions more or less the As enrichment in the region. According to the sequential extraction tests utilized, in all the soils and sediments samples, the soluble and exchangeable fractions exhibited extremely lower values corresponding less than 2% of the total As in these samples. These results showed low availability of As to the environment by the soils and sediments in Paracatu. The mobility of the exchangeable As in the soils of Paracatu was assessed through column leaching experiments. The results showed an association of the As with the Fe oxides and hydroxides which favors to retain this metalloid even in the exchangeable fraction in the soils. According to the results of this and other studies, an addition of Ca to the contaminated soils favors the process of the As retention, showing great potential in the use of compounds of this element in strategies that aimed at the remediation of contaminated areas
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Développements spectroscopiques pour l'étude de la matière organique du sol dans des extraits liquides, avec étude de son impact sur le comportement des métaux : application à un sol agricole amendé par du compost

Mouloubou, Olsen 22 July 2015 (has links)
L'évolution de la législation en matière de valorisation des déchets organiques incite au développement de filières de valorisation, parmi lesquelles le compostage présente un intérêt d'amendement pour les sols, lié notamment à la présence de substances humiques. La matière organique (MO) est une composante importante du sol en raison de son rôle dans les équilibres physiques, chimiques et biologiques, ainsi que par son implication dans le comportement des métaux et métaux traces (MMT). Les objectifs de cette thèse étaient de développer une approche méthodologique afin de caractériser la MO du sol (MOS) et étudier son évolution spatio-temporelle suite à l’apport d’un compost sur une année et 2 profondeurs, et d'approcher son impact sur le comportement des MMT. Une procédure d’extraction séquentielle en 4 étapes (eau, acide, soude, pyrophosphate) a été réalisée afin de fractionner la MOS. Des analyses quantitatives et qualitatives, ont été effectuées sur les extraits. La procédure de fractionnent chimique a permis de distinguer plusieurs catégories de composés organiques (labiles, fulviques et humiques plus ou moins aromatiques). Les analyses quantitatives et les réponses spectrales sur les extraits ont révélé un effet compost essentiellement les trois premiers mois après l’épandage et en été, avec un impact des paramètres climatiques au cours de l'année, mais pas au-delà de 15 cm. Le compost peut apporter au sol une charge supplémentaire en MMT, notamment potentiellement mobilisables, avec un risque de contamination modéré, mais non négligeable lié aux effets potentiels d’accumulation et de concentration sur le long terme. / The evolution of the legislation regarding the valorization of biowaste (green manure) induces the development of valorization chains, among which amending soils with compost is of particular interest, due to the presence of humic substances. Organic matter (OM) is an important component of the soil due to its physical, chemical and biological participation, and its implication in the behaviour of metals and trace metals (MTM).The aims of this thesis were to develop a methodological approach to characterize OM of soil (SOM) and to study its spatiotemporal evolution over one year at two different depths following the addition of compost, and its impact on the behaviour of MTM. A 4-step sequential extraction procedure (water, acid, sodium hydroxide, pyrophosphate) was used to the SOM fractionation. Quantitative and qualitative analysis were applied on extracts. Solubilization kinetics of MTM was also carried out to refine the study of their mobility.The chemical fractionation procedure allowed distinguishing several classes of organic compounds (labile, fulvic and humic with various aromaticity). Quantitative analyzes and spectral responses of the extracts revealed an effect of the compost (organic carbon, metals, aromaticity and molecular weight compounds) essentially during the first three months after spreading and during the summer period, with a climate parameter effect during the year, but not beyond 15 cm of depth. Compost can bring to the soil an additional load of MTM, including potentially mobilized forms, with a moderate, but not negligible risk of contamination, due to the potential effects of accumulation and concentration over the long term.
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A Geochemical and Mineralogical Comparison of Soil Formation on Mine Spoil and Undisturbed Shale and their Contributions to Pore Water, Huff Run Watershed, Ohio

Zemanek, Laura Marie 11 October 2021 (has links)
No description available.

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