The hypothesis for this study was that phenanthrene degrading bacterial inoculants, in combination with grass species able to tolerate petroleum hydrocarbon contamination, will result in increased degradation, as compared to natural rates of hydrocarbon degradation, or to rates of degradation attributed to bacteria or plants alone. Three experiments were performed to examine this hypothesis: i) assessment of the effect of phenanthrene degrading bacteria (<i>Sphingomonas yanoikuyae</i>, <i>Rahnella aquatilis</i>, and <i>Arthrobacter globiformis</i>) on seed germination, location of attachment on seeds and roots, and inoculant survival on selected grass species, ii) determination of the inoculant survival in contaminated soil in the absence of plants and the ability to degrade target compounds, and iii) degradation potential and survival of selected grass species and bacterial inoculants in soil. In general, all applied inoculants were able to effectively colonize the seeds and had a neutral or positive effect on seed germination and seedling growth. Possible plant and bacteria pairs were chosen based on positive influence of the inoculant and are as follows: perennial ryegrass (<i>Lolium perenne</i>) or creeping red fescue (<i>Festuca rubra</i>) with <i>A. globiformis</i> or <i>S. yanoikuyae</i>, or slender wheatgrass (<i>Elymus trachycaulus</i>) with <i>A. globiformis</i> or <i>R. aquatilis</i>. Soil-based assessment of the survival and degradation of hydrocarbons by the selected inoculants was examined with or without a manure nutrient amendment. The addition of the inoculants had a positive impact on the efficacy of hydrocarbon removal in the soil. The manure-amended soil, or <i>A. globiformis</i> inoculated non-amended soil treatments reduced total petroleum hydrocarbon concentration by ~45%, whereas the non-amended control only resulted in a ~20% reduction. When soils were amended with manure and inoculated with any of the phenanthrene degrading bacteria, contaminant concentration decreased in soil by ~33%. <i>Sphingomonas yanoikuyae</i> survived the longest in soil in the absence of plants. A growth chamber experiment was conducted to determine the efficacy of plant and bacteria pairs for hydrocarbon removal in recalcitrant contamination found in soil from Bruderheim, Alberta. Additional replicates containing this soil were spiked with hexadecane, phenanthrene, and pyrene so the effectiveness of the plant and bacteria pairs at higher levels of fresh contamination could be assessed. In the spiked treatment, inoculation with <i>S. yanoikuyae</i> increased creeping red fescue root biomass. In the non-spiked treatment, <i>S. yanoikuyae</i> application increased creeping red fescue root and shoot biomass. Perennial ryegrass root and shoot biomass did not increase when inoculated with <i>S. yanoikuyae</i>, although root biomass values were observably higher in non-spiked soils. Creeping red fescue inoculated with <i>S. yanoikuyae</i> resulted in the greatest decrease in hydrocarbon concentration as compared to other treatments (~61%). The perennial ryegrass treatment, when inoculated with <i>S. yanoikuyae</i> increased percent hydrocarbon removal (~10%) above that obtained with perennial ryegrass alone. The addition of plants and <i>S. yanoikuyae</i> increased hydrocarbon degradation relative to control soils, although the addition of vegetation alone had a comparable effect. A critical benefit of inoculation was the increase in creeping red fescue root biomass at higher concentrations of contamination. This is important because the larger the root biomass the larger the volume of soil that can be remediated. The results indicate that the use of specific plant-bacterial inoculants can enhance remediation of hydrocarbon contaminated soils.

Made available in DSpace on 2015-03-26T13:27:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1452427 bytes, checksum: ad89ed1f2acb1864018bdd4b54b3fc9e (MD5) Previous issue date: 2008-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research addressed the application of electrokinetic phenomena in soil remediation, considering the application of electroosmosis in the decontamination of three soils from the Zona da Mata Norte, Minas Gerais state, Brazil, contaminated with the element-trace cadmium. This work followed a line of research previously developed at the Universidade Federal de Viçosa, including the evaluation of the electroosmotic process in the chemical and mineralogical parameters of a larger gamma of soils, as well as evaluating the effect of testing parameters in the efficiency of the decontamination process. The tested soils were residual products from gneiss, as follow: (i) soil 1, a mature residual soil, pedologically classified as Red Yellow Latosol, presenting lateritic geotechnical behavior and silty-sandy-clayey texture; (ii) soil 2, saprolitic, presenting non lateritic geotechnical behavior and clayey-silty-sandy texture; e (iii) soil 3, also a mature residual soil, pedologically classified as Red yellow Podzol (Argisol), presenting non- lateritic geotechnical behavior and sandy-siltyclayey texture. Cadmium was the element- trace used in the experiment because it is a usual polluting source in daily use objects and presents adsorption-desorption intermediate behavior. The study program was directed to the analysis of soil behavior before and after their contamination with cadmium, encompassing the following steps: (i) X-rays analysis; (ii) physical and chemical routine tests; (iii) determination of CEC and ZPC; (iv) evaluation of the influence of the applied compaction effort and, therefore, of structure, in the soils eletrosmotic conductivity coefficient; (v) evaluation of the influence of the applied electrical potential difference (ddp) of 5, 15 and 30 V in the electrokinetic decontamination process; (vi) analysis of the influence of the contaminant incubation time (periods of 1, 10 and 20 days) and of ddp (5, 15 and 30 V) in the decontamination process. The results had shown that: (i) quartz predominated in the soils sand fraction, whereas kaolinite predominated in the soils silt and clay fractions; however, it was observed significant presence of hematite and gibbsite in the clay fraction of soil 1 and of goethite in the clay fraction of soil 3; (ii) electrochemically, soils 1 and 3 revealed more active behavior, presenting higher specific cation adsorption capacity; (iii) the parameter ZPC was a determinant factor in all the analyzed soils chemical properties, as well as in the electrokinetic decontamination process, governing the direction of the eletrosmotic flow and influencing in the results of the decontamination applied technique; (iv) the addition of the contaminant to soils was responsible for significant changes in the routine analysis and in the CEC and ZPC parameters, specially regarding soils 1 and 3, which are the most active ones; (v) except for soil 3, the values of the electroosmotic conductivity coefficient of soil was not significantly influenced by the application of different electric potentials and different compaction efforts; (vi) for all tested soils, cadmium soils removal through electrokinetic phenomena increased significantly with the increase of the incubation time and with the increase of the applied electric potential difference. / O presente trabalho abordou a aplicação de fenômenos eletrocinéticos na remediação de solos, com um direcionamento ao emprego da eletrosmose na descontaminação de três solos da Zona da Mata Norte, estado de Minas Gerais, Brasil, contaminados com o elemento- traço cádmio. Buscou-se ampliar o horizonte de pesquisas já desenvolvidas na Universidade Federal de Viçosa, com a inclusão da avaliação do processo eletrosmótico em parâmetros químicos e mineralógicos de uma gama maior de solos, bem como avaliar o efeito de diferentes vairáveis na eficiência do processo de descontaminação. Trabalhou-se com solos residuais de gnaisse, como se segue: (i) solo 1, um residual maduro, pedologicamente classificado como Latossolo Vermelho-Amarelo, de comportamento geotécnico laterítico e textura argilo-areno-siltosa; (ii) solo 2, saprolítico, de comportamento geotécnico não laterítico e textura areno- silto-argilosa; e (iii) solo 3, também, residual maduro, pedologicamente classificado como Argissolo Vermelho- Amarelo, de comportamento geotécnico não laterítico e textura argilo-areno-siltosa. O elemento-traço empregado foi o cádmio, fonte poluidora presente em objetos de uso diário e que apresenta comportamento adsorção-dessorção intermediário. O programa de estudo foi dirigido aos solos antes e após contaminação com cádmio e abrangeu a realização de: (i) análises de difração de raios-X; (ii) análises de laboratório para determinação de propriedades física e química; (iii) determinações de CTC e PCZ; (iv) avaliação da influência da energia de compactação e, portanto, da estrutura, no coeficiente de condutividade eletrosmótica dos solos; (v) avaliação da influência da diferença de potencial elétrico aplicado (ddp) no processo de descontaminação eletrocinética, trabalhando-se com valores de 5, 15 e 30 V; (vi) análise da influência do tempo de incubação do contaminante (períodos de 1, 10 e 20 dias) e da ddp (5, 15 e 30 V) na descontaminação dos solos. Os resultados mostraram que: (i) na fração areia dos solos estudados, havia predomínio de quartzo, enquanto que nas frações argila e silte, havia dominância de caulinita; no entanto, observou-se presença expressiva de hematita e gibbsita, no solo 1, e de goethita, no solo 3; (ii) os solos 1 e 3, do ponto de vista eletroquímico e ambiental, mostraram-se mais ativos, podendo apresentar alta adsorção específica de cátions; (iii) o PCZ foi um fator determinante em todas as propriedades dos solos estudados, bem como no processo de descontaminação eletrocinética, mostrando-se associado o sentido do fluxo eletrosmótico aos resultados dos ensaios de descontaminação; (iv) a adição do contaminante aos solos produziu variações significativas nos seus parâmetros químicos obtidos via análises de rotina, CTC e PCZ, em especial no caso dos solos 1 e 3, mais ativos; (v) os valores do coeficiente de condutividade eletrosmótica não variaram significativamente com a aplicação de diferentes potenciais elétricos e de diferentes energias de compactação, exceto para o solo 3, provavelmente devido a fatores mineralógicos dos solos; (vi) a remoção de cádmio dos solos, através dos fenômenos eletrocinéticos, aumentou significativamente com o aumento do período de incubação e com o aumento da diferença de potencial elétrico aplicado, para todos os solos estudados.

Neun Fachbeiträge dokumentieren die Ergebnisse der aktuellen Projekt- und Forschungsarbeit des Landesamtes in den Themenbereichen Grundwasser, Altlasten und Boden.

Purpose: In Sweden, there are area that are polluted and in need of remediation. However, soil remediation processes have a negative secondary impact on the climate. There are various soil remediation methods to apply, of which dig and dump are the most frequently used. The method involves although high emissions of carbon dioxide. By increased use of alternative soil remediation methods, such as biological soil remediation methods, can lead to reduced impact on the climate. When choosing a remediation method, sustainability is increasingly integrated, but most decisions are still based on other factors. Psychological, social and institutional barriers are considered to have counteracted the assumption of a sustainable behaviour. Therefore, further research on stakeholder attitudes may promote the implementation of such behaviour. The aim of the work is to present suggestions for improvement on how the climate impact can be reduced in soil remediation projects. Method: The study was performed as a qualitative survey. Empirical data was obtained in verbal form through the methods literature review, document analysis and interview. From an available group, six respondents were selected who represent significant stakeholders in soil remediation projects. Stakeholders were private and public clients, contractors, consultants and regulators. Analysed documents were reports from the Swedish Environmental Protection Agency that is about the post-treatment of contaminated areas in Sweden. Findings: The study indicates that biological soil remediation methods have a lower impact on the climate than dig and dump. Furthermore, it appeared that the main factors in choosing a soil remediation method was type of contamination, time for remediation and when contamination is detected in projects. According to this background, biological methods are less applied than dig and dump. However, the study presents suggestions for improvements of how biological alternatives can be encouraged, for instance are more reference objects needed where biological soil remediation methods have been applied. Implications: One conclusion from the study is that existing regulations should be changed to make landfill more difficult and to facilitate re-use of polluted masses, and the fees for landfill should be increased. In addition, more reference objects need to be generated in Sweden that validate that biological soil remediation methods achieve acceptable levels of pollution. Furthermore, stakeholders in soil remediation projects should cooperate more, even across national borders, and together venture to try biological soil remediation methods. Limitations: The result is only valid for biological soil remediation methods and dig and dump for organic pollutants in soil. The study includes few respondents from av geographic limited available group, which means that the result cannot be generalized with certainty. Therefore, the study should be regarded as exploratory and the results thereafter. / Syfte: I Sverige återfinns områden som är förorenade och i behov av efterbehandling, dock har marksaneringsprocesser en negativ sekundär påverkan på klimatet. Det finns olika markasaneringsmetoder att tillämpa varav schakt och deponering är den mest frekvent använda. Emellertid innebär metoden höga utsläpp av koldioxid. Tillämpning av alternativa åtgärder, såsom biologiska marksaneringsmetoder, kan bidra till lägre koldioxidutsläpp. Vid val av saneringsmetod integreras hållbarhet alltmer, men de flesta besluten baseras ändå på andra faktorer. Psykologiska, sociala och institutionella hinder anses ha motverkat antagandet av ett hållbart beteende. Därför kan fortsatt forskning om intressenters inställning främja implementering av ett sådant beteende. Målet med arbetet är att presentera förbättringsförslag på hur klimatpåverkan kan minskas vid marksaneringsprojekt. Metod: Arbetet utfördes i form av en kvalitativ kartläggning. Insamling av empiri skedde i verbal form genom datainsamlingsmetoderna litteraturstudie, dokumentanalys och intervju. Ur en tillgänglig grupp valdes sex stycken respondenter som representerar betydande intressenter vid marksaneringsprojekt. Intressenterna var privat- och offentlig beställare, entreprenör, konsult samt tillsynsmyndigheter. Dokument som analyserades var rapporter från Naturvårdsverket som behandlar efterbehandling av förorenade områden i Sverige.  Resultat: Studien indikerar att biologiska marksaneringsmetoder har lägre klimat-påverkan än schakt och deponering. Vidare framgick att de främsta faktorerna vid val av marksaneringsmetod var typ av förorening, saneringstid och när föroreningen upptäcks i projekt. Med denna bakgrund tillämpas biologiska åtgärder mer sällan än schakt och deponering. Emellertid presenterar studien förbättringsförslag till hur tillämpning av biologiska alternativ kan främjas, bland annat behövs fler referensobjekt där biologiska marksaneringsmetoder tillämpats.  Konsekvenser: En slutsats från studien är att gällande regelverk bör förändras för att försvåra deponering och underlätta återanvändning av förorenade massor samt bör avgifterna för deponering höjas. Dessutom behöver fler referensobjekt genereras i Sverige som påvisar att biologiska marksaneringsmetoder uppnår godkända föroreningshalter. Vidare bör intressenterna vid marksaneringsprojekt samarbeta mer, även över nationella gränser, för att tillsammans våga tillämpa biologiska mark-saneringsmetoder.  Begränsningar: Resultatet är endast giltigt för biologiska marksaneringsmetoder samt schakt och deponering av organiska föroreningar i mark. Studien inkluderar få respondenter ur en geografiskt begränsad tillgänglig grupp, vilket gör att resultatet inte med säkerhet kan generaliseras. Därmed bör studien betraktas som utforskande och resultatet därefter.

Kartotrak software allows optimal waste classification and avoids unnecessary remediation. It has been designed for those - site owners, safety authorities or contractors, involved in environmental site characterization projects - who need to locate and estimate contaminated soil volumes confidently.

Kartotrak software allows optimal waste classification and avoids unnecessary remediation. It has been designed for those - site owners, safety authorities or contractors, involved in environmental site characterization projects - who need to locate and estimate contaminated soil volumes confidently.

Ce travail a pour objectif de tester des solutions viables et durables pour la phytoremédiation de sols contaminés en éléments traces. Il inclut à la fois des données sur l'évaluation initiale et résiduelle des risques (biomonitoring) et sur des solutions de phytomanagement à long terme utilisant des plantes et microorganismes associés, en particulier la phytoextraction aidée couplant l’épuisement du pool labile de contaminants du sol, la production de matière première végétale et la restauration de services écosystémiques. La phytotoxicité du Cu, le rôle améliorant des amendements organiques et minéraux et la tolérance des plantes ont été examinés utilisant des essais biologiques ainsi qu’une technique de dilution du sol. L'utilité d’une lignée de mutant de tournesol (Helianthus annuus) et d’une lignée parental de tabac (Nicotiana tabacum) pour le biomonitoring de sols contaminés en Cu a été investiguée. Les paramètres biochimiques qui sont en relation avec le statut antioxidant des plantes et leurs réponses moléculaires à l’excès de Cu ont en général montré une plus grande sensibilité que les traits morphologiques. Le tabac est plus tolérant au Cu que le tournesol. Des bactéries endophytes issues de différentes sources, notamment des graines d’une population métallicole d’une graminée (Agrostis capillaris) peuvent stimuler la croissance du tournesol et du tabac aux expositions en Cu modérément en excès. Pour ces plantes annuelles, accumulatrices secondaires du Cu et à phénotype d’exclusion, l'augmentation de la capacité de phytoextraction de Cu par les parties aériennes s’effectue principalement par l’accroissement de la biomasse aérienne, plutôt que par celui de sa concentration en Cu. Par conséquent, une attention a été prêtée aux pratiques agricoles dans les essais en parcelles sur site. Plusieurs options d’amélioration ont été examinées in situ: l'application d’amendements du sol, l'utilisation de lignées de mutants et de variants somaclonaux, la rotation de cultures et des cultivars, la bioaugmentation, la fertilisation, l’irrigation, etc. Deux lignées de mutants et des cultivars commerciaux de tournesol ainsi qu’une lignée parentale de tabac ont montré un fort potentiel pour la phytoextraction du Cu, accompagné d’une production significative de graines et/ou autre biomasse valorisable. Les solutions de restauration écologique basées sur la phytoextraction, utilisant des plantes annuelles accumulatrices secondaires de Cu permettraient (1) la décontamination progressive des sols contaminés en Cu au cours des rotations culturales, (2) un retour financier lié à la valorisation de la biomasse végétale, et (3) la restauration de services écosystémiques. / This work aimed at assessing sustainable phytoremediation options for trace element-contaminated soils. It includes both the assessment of initial and residual risks (biomonitoring) and long-term sustainable decontamination options using plants and associated microbes, especially aided phytoextraction with the secondary purposes of producing plant-based feedstock and restoring ecosystem services. Copper phytotoxicity, the improving role of soil conditioners, and plant tolerance were tested using a bioassay as well as a fading technique. The usefulness of a mutant line of sunflower (Helianthus annuus) and a motherline of tobacco (Nicotiana tabacum) for the biomonitoring of Cu-contaminated soils was investigated. Biochemical parameters in relation to antioxidant status of plants and molecular responses to Cu excess generally showed a greater sensitivity than morphologic ones. Tobacco has a higher Cu tolerance than sunflower. Endophytic bacteria from various sources, notably from the seeds of metallicolous populations of grasses (Agrostis capillaris) can promote the growth of sunflower and tobacco exposed to Cu excess. For annual Cu-secondary accumulator plants with an excluder phenotype, increase in shoot Cu removal occurred primarily through increase in shoot biomass, rather than in shoot Cu concentration. Therefore, attention in field trials was paid to agricultural practices. Various improving options were tested in situ: application of soil amendments, the use of mutant lines and somaclonal variation, cultivars and crop rotation, bioaugmentation, fertilization, irrigation, etc. Two mutant lines and some commercial cultivars of sunflower as well as the motherline of tobacco showed a high potential for Cu phytoextraction as well as for plant-based feedstock. Ecological restoration options for Cu-contaminated soils based on phytoextraction using annual Cu-secondary accumulator plants with a high shoot biomass would (1) result in the progressive decontamination of Cu-contaminated soils during crop rotations, (2) provide a financial return through biomass valorization, and (3) promote ecosystem services.

The continuity of the menace of mercury (Hg) is due to the continuous production and use of Hg and Hg containing products. Toxicity is just an outfall of use and exposure. Anthropogenic activities such as coal combustion and artisanal and small-scale gold mining have led to increasing Hg contamination and is the major source of Hg pollution into the environment that needs to be remediated. This study aimed to assess the phytoextraction capability of sweet sorghum (Sorghum bicolor) under different fertiliser treatments in Hg-contaminated soil. The potted experiment in a controlled environment included control S. bicolor and three phytoremediation treatments, i.e., Hg only; the addition of 4:1 green compost and; the addition of 0.2% NPK fertiliser. There were conspicuous signs of Hg phytotoxicity in plants with Hg only, namely wilting, senescent, inhibition of growth, and photosynthesis. There was stunted growth, but healthy plants observed in the treatment with the addition of green compost towards the end (day 60) of exposure. However, S. bicolor grew well until the last day of exposure in the treatment with the addition of 0.2% NPK fertiliser. Thus, this treatment showed the most effective phytoextraction potential of S. bicolor in Hg-contaminated soil. The effectiveness of S. bicolor in reducing the level of mercury was best assessed in the Hg bioavailable concentration in the spiked soil in which the Hg + NPK treatment has the lowest (0.77 mg kg−1). That resulted in the highest uptake (84.31%) percentage of Hg concentration recorded in the treatment with the addition of 0.2% NPK fertiliser compared to the other two treatments. The results suggest that the proportion of phosphate in the NPK fertiliser used, plays a huge role in the phytoextraction of Hg in the contaminated soil by S. bicolor. The Translocation Factor (TF) and Bioconcentration Factor (BCF), although higher within Days 20 and 40, was greater than 1 at the end of the exposure period suggesting a high probability that Hg was significantly transferred to the aerial parts of the plants. This is regarded as typical hyperaccumulator plant species. While S. bicolor was able to reduce the level of Hg in all three treatments, Hg + NPK treatment gave overall best results in physiological growth, the uptake, and reducing the level of Hg bioavailable in the spiked soil in terms of the effectiveness of phytoremediation method. / Environmental Sciences / M. Sc. (Environmental Science)