Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-09-24T19:29:23Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Anderson_Rosa_2018.pdf: 394581 bytes, checksum: 96f973e7cdd32576a855f0e1dfd0f946 (MD5) / Made available in DSpace on 2018-09-24T19:29:23Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Anderson_Rosa_2018.pdf: 394581 bytes, checksum: 96f973e7cdd32576a855f0e1dfd0f946 (MD5) Previous issue date: 2018-03-27 / The production of animal protein in confined space is an activity that has been highlighting in the western region of Paraná, due to the increase in the demand for food. The use of organic wastes as fertilizers is a profitable practice for the rural producer, but the application of high amounts and in a continuous way can cause accumulation of nutrients, biological agents as well as oils and greases that can cause environmental problems. The objective of this work was to evaluate the accumulation of phosphorus, potassium, copper, iron, manganese, zinc, oils and greases in Oxisols fertilized with swine manure. The experiments were installed in two municipalities in the state of Paraná. In Santa Tereza do Oeste it started in 2015. The treatments were three doses of liquid swine manure, on average, 50; 100 and 150 m³ ha-1 year-1 one control and one treatment with chemical fertilization using NPK formulated. In Palotina it was started in 1997 and the treatments were three doses of liquid swine manure, 30, 60 and 120 m³ ha-1 and one control. The experimental design was a randomized block with four replications in plots of 50 m2. Soil sampling was performed before planting the 2017/2018 crop in each plot at 0-5 and 5-10 cm depths. Contents of P, K, Cu, Fe, Mn and Zn were evaluated by the Mehlich-1 method and the oil and grease content by the Soxhlet lipid extractor with organic solvent hexane. The data were submitted to analysis of variance and the averages were compared by the Tukey test at 5% probability. The application of swine manure influenced the levels of phosphorus, potassium, copper, manganese, zinc, oils and greases of the soil in the areas sampled, with a higher concentration observed in the 0-5 cm depth layer. The doses of the swine manire contributed significantly to the increase of phosphorus, potassium, copper, zinc, and oils and greases concentrations in the soil. / A produção de proteína animal em espaço confinado é uma atividade que vem se destacando na região Oeste do Paraná, devido ao aumento da demanda por alimentos. O uso de resíduos orgânicos como fertilizantes é uma opção rentável ao produtor rural, porém a aplicação de quantidades elevadas e de maneira contínua pode ocasionar acúmulo de nutrientes e também óleos e graxas, podendo causar problemas ambientais. O objetivo desse trabalho foi avaliar o acúmulo de fósforo, potássio, cobre, ferro, manganês, zinco, óleos e graxas em Latossolos adubados com dejeto de suínos. Os experimentos foram instalados em dois municípios do estado do Paraná. Em Santa Tereza do Oeste, iniciou-se em 2015. Os tratamentos foram três doses de dejeto líquido de suínos: 50, 100 e 150 m³ ha-1 ano-1 (em média), uma testemunha e um tratamento com adubação química utilizando-se formulado NPK. Em Palotina, iniciou-se em 1997 e os tratamentos foram três doses de dejeto líquido de suínos: 30, 60 e 120 m³ ha-1 ano-1 e uma testemunha (sem aplicação). O delineamento experimental foi o de blocos casualizados com quatro repetições, em parcelas de 50 m2. A amostragem do solo foi realizada antes do plantio da safra 2017/2018 em cada parcela, nas camadas de 0-5 e 5-10 cm. Teores de P, K, Cu, Fe, Mn e Zn foram avaliados pelo método Mehlich-1 e os teores de óleos e graxas por meio do extrator de lipídios Soxhlet, com solvente orgânico hexano. Os dados foram submetidos à análise de variância e o as médias foram comparadas pelo teste de Tukey a 5 % de probabilidade. A aplicação de dejeto líquido de suínos influenciou os teores de fósforo, potássio, cobre, manganês, zinco, óleos e graxas do solo nas áreas amostradas, com concentração maior observada na camada de 0 - 5 cm de profundidade. As doses do dejeto líquido de suínos contribuíram significativamente para o aumento das concentrações de fósforo, potássio, cobre, zinco e óleos e graxas no solo, sendo que o maior volume de dejeto líquido de suínos aplicado proporcionou maior concentração desses elementos no solo.

Estudos recentes constataram a existência de processos que permitem a atenuação natural dos contaminantes presentes nos lixiviados. O adequado entendimento destes processos pode originar benefícios possíveis de serem aplicados em aterros antigos, novos ou naqueles que ainda serão concebidos. O presente estudo avaliou o comportamento e a atenuação de contaminantes dos líxiviados no solo, por meio de experimento desenvolvido em colunas de percolação e, para a avaliação da atenuação este teste é indicado por refletir as condições naturais e as características adsortivas do solo, propiciando uma melhor simulação da atenuação. O lixiviado e o solo utilizados neste experimento são provenientes do aterro sanitário de São Carlos - SP. O solo utilizado foi caracterizado quanto à composição física, química, biológica e mineralógica para verificar o transporte do percolado nas colunas e a interação solo-contaminante. Na área do aterro foram feitas perfurações, ensaios de condutividade hidráulica e avaliação da geologia local, para conhecimento das características físicas, químicas, biológicas, mineralógicas e geológicas do solo in situ. Este foi classificado como arenoso, apresentando características físicas e químicas que não se enquadram nos parâmetros adequados para sua utilização em áreas de disposição de resíduos sólidos urbanos, pois, a capacidade de troca de cátions, superfície específica, potencial hidrogeniônico e classe textural arenosa, evidenciam que este solo possui deficiente capacidade de retenção e imobilização de contaminantes. Além disso, pela observação in situ, constata-se que a área de disposição de resíduos sólidos de São Carlos esta situado sobre rochas da Formação Botucatu, sendo que a mineralogia do solo presente no local é composta de quartzo, caulinita, goethita, hematita, gibsita e ilita. O ensaio de condutividade hidráulica indicou que o solo presente na base do Aterro sanitário não atende a valor de permeabilidade exigida por norma, o que poderá permitir a infiltração de água da chuva, aumentando a produção do lixiviado e sua movimentação no perfil, podendo atingir as águas subterrâneas. Assim, foram traçadas curvas características do transporte de contaminantes nas amostras efluentes monitoradas durante o processo de percolação, coletadas a cada 0,25 volume de poros até atingir 10,0 volume de poros percolados. As curvas características do transporte de contaminantes traçadas apresentaram baixas concentrações de Chumbo, Cádmio, Ferro, Zinco, Manganês, Cálcio, Magnésio, Cobre, Cromo nas amostras fluentes. Já o Sódio, Potássio, Cloro, Níquel e Alumínio foram preferencialmente percolados com o lixiviado, evidenciando a variação da faixa de concentração de cada elemento no percolado. Os perfis de concentração dos metais pesados mostraram que existe uma frente de contaminação. As curvas de retenção de metais no solo mostraram que a preferência de sorção apresentada pelos solos nas colunas foi : Cobre > Cádmio > Cálcio > Zinco > Magnésio > Potássio > Manganês > Fósforo > Ferro > Níquel > Alumínio. Cujos valores retidos no solo das colunas podem estar evidenciando a capacidade deste solo em reter contaminantes.O solo em questão apresentou baixo potencial para retenção dos contaminantes presentes no lixiviado, classificado como arenoso e, com características químicas que não se enquadram nos parâmetros adequados para sua utilização em áreas de disposição de resíduos sólidos urbanos. / Recent studies had found the existence of processes that allow a natural attenuation of the leachates\'s cotaminants. An adequate understanding of these processes may originate benefits, that may be applied in ancient, new or to be created landfills. This work evaluated the contaminant\'s behavior and attenuation, contaminants existing in soil\'s leaching, throughout an experiment developed in percolation columns. This is the indicated examination for evaluate the attenuation, because it reflects soil\'s natural conditions and adsorptive characteristics, providing a better simulation of it\'s attenuation. The leachate and the soil used in this experiment came from Sao Carlos-SP landfill. The used soil has been characterized as its mineralogical\'s and physical chemical-biological\'s composition, looking for the percolated\'s transportation inside the columns, and for the interaction soil-contaminant. The landfill\'s area has been several times drilled, tested as it\'s hydraulic conductivity and assessment of local geology, in order to know the physical, chemical, biological, mineralogical and geological in situ soil\'s characteristics. This, has been classified as sandy, and, by presenting chemical characteristics that does not reach the adequated value for utilization on solid urban wastes, due to the values of CTC, SE, pH, and the textural sandy class, what shows a deficient buffering capacity in retaining and immobilisating contaminants. By observation in situ, has been found that Sao Carlos\'s solids disposal waste is located over rocks from the Botucatu formation, and the mineralogy of it is composed of quartz, caulinith, goethith, hematith, gibsith an ilith. The hydraulic conductivity test has indicated that the soil in the base of the sanitary landfill does not reaches the permeability values required by the standards, what may allow rain water\'s infiltration, and raises the amount of leachate and it\'s movement onto the ground, and even the leachete to reach the underground waters. So, has been drawn the characteristics curves of the contaminant\'s transportation in the effluents samples found during the percolation process, collected by every 0,25 VP until it reaches 10,0 VP percolated. The characteristical curves of the contaminant\'s transportation drawn showed low concentrations in the effluent samples of Lead, Cadmium, Iron, Zinc, Manganese, Calcium, Magnesium, Cooper, Chromium. Also, Sodium, Potassium, Chlorine, Nickel and Aluminium had been preferencially percolated within the leachate, what evidentiates the variation in the range of concentrations of every percolated element. The concentration profiles from heavy metal\'s had shown that there is a front of contamination. The retention curves from the soil\'s retaining metal showed that the preferency for the sorption was: Cooper > Cadmium > Calcium > Zinc > Magnesium > Potassium > Manganese > Phosphorus > Iron > Nickel > Aluminium, whose values may point the soil\'s ability in retaining contaminants. The studied soil has presented low potential in retain contaminants from the leachete, and is characterized as sandy, and it\'s chemical features shall not be framed according the standards parameters to be utilized in solid urban waste\'s disposal.

The distribution of heavy metals between soil and soil solutions is a key issue in evaluating the environmental impact of long term applications of heavy metals to land. Contamination of soils by heavy metals has been reported by many workers. Metal adsorption is affected by many factors, including soil pH, clay mineralogy, abundance of oxides and organic matter, soil composition and solution ionic strength. The pH is one of the many factors affecting mobility of heavy metals in soils and it is likely to be the most easily managed and the most significant. To provide the appropriate level of protection for aquatic life and other uses of the resource, it is important to be able to predict the environmental distribution of important metals on spatial and temporal scales and to do so with particular emphasis on the water column concentrations. Regulatory levels reflected in water quality criteria or standards are based on water column concentrations. Predicting water column concentrations requires a consideration of the interactions of water column contaminants with both bed sediments and suspended particulates as critical components in the assessment. The adsorption behaviour of cadmium, copper, lead and zinc onto soils is studied under the various geo-environmental conditions of pH, concentration of adsorbate and adsorbent, and solution compositions. Experiments were conducted to determine the equilibrium contact time of various adsorbates for adsorbent in different systems. Experiments were also conducted to check the efficiency of various acid-mixtures to extract heavy metal from soils into the aqueous phase. The adsorption behaviour of heavy metals onto soils was also studied from sea-water system. Soils are characterized in terms of the role of clay minerals to remove the metals from the solution phase, back-ground levels of metals, maximum adsorption capacity to adsorb various heavy metals from different adsorption systems, and type of surface sites present. The experimental data of metal adsorption is described by Langmuir adsorption model. The adsorption data are also expressed in terms of surface loading, surface acidity, adsorption density, and affinity of soils for heavy metals in different adsorption systems. Ecological implications of changes in physical and chemical conditions in aquatic systems on heavy metals uptake by soils are also discussed. This research covers the following areas: the environmental impact of heavy metal discharge into the aquatic systems, the study of the mobility patterns of different heavy metals as function of geo-environmental conditions, and determination of the pathways and the ultimate fate of heavy metals in the environment.

The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.

Orientador: Jarbas José Rodrigues Rohwedder / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-27T15:32:58Z (GMT). No. of bitstreams: 1 Santos_LiviaMartinsdos_D.pdf: 6212654 bytes, checksum: f20eb97ce2aae510654340b401468dd2 (MD5) Previous issue date: 2015 / Resumo: A contaminação de solos oriundos de derrames de compostos derivados do petróleo é um problema que representa riscos ao meio ambiente e a população. Dentre os constituintes do petróleo, os BTEX são os mais tóxicos. O uso da espectroscopia no infravermelho próximo (NIR) foi empregado como uma ferramenta analítica visando a determinação de BTEX em amostras de solo. À um espectrofotômetro construído no laboratório foi adaptado uma célula de medida, uma célula de amostra e uma válvula esfera responsável pela conexão entre essas duas células. Uma bomba de vácuo foi adaptada ao instrumento visando facilitar o enriquecimento da fase vapor dos hidrocarbonetos voláteis na célula de medida, a qual operou com uma pressão de 29,0 inHg abaixo da pressão do laboratório (APL). Os espectros obtidos da fase vapor contendo os hidrocarbonetos aromáticos apresentaram sobreposição de bandas de absorção. Desta forma, foi necessária a construção de modelos de calibração multivariados empregando Regressão por Mínimos Quadrados Parciais (PLS). Os resultados do melhor modelo de regressão obtidos a melhores condições experimentais mostraram que os valores de RMSECV foram de 12,4 mg kg-1, 47,3 mg kg-1, 72,4 mg kg-1 e 58,6 mg kg-1, respectivamente, para benzeno, tolueno, etilbenzeno e xilenos. Esses valores estão de acordo com os valores orientadores para solo da CETESB de 2005, com exceção para o benzeno que encontra-se acima do valor permitido. Para cada tipo de solo é necessário a construção de modelos de calibração, pois a composição do solo influencia na determinação dos hidrocarbonetos / Abstract: The contamination of soils due to petroleum compounds spills is a problem that represents risks to environment and population. Among petroleum constituents, the volatile aromatic hydrocarbons known as BTEX are toxic. This study aims to evaluate the use of near infrared spectroscopy as an analytical tool for determination of volatile hydrocarbons in soil samples. Spectra were obtained in a spectrophotometer built in the laboratory. It is also part of the instrument, a measuring cell with 540 mm of optical path, a sample cell and a valve which allows connection between the two cells. A vacuum pump was adapted to the instrument in order to facilitate enrichment of the vapor phase of the volatile hydrocarbons in the measuring cell, which operated at a pressure of 29.0 inHg below of the laboratory pressure (BLP). Spectra of the vapor phase containing aromatic hydrocarbons exhibited overlapping of absorption bands. Thus, it was necessary to construct multivariate calibration models using Partial Least Squares Regression (PLS). The results obtained for the calibration model provided values of RMSECV of 12.4 mg Kg¬-1, 47.3 mg Kg¬-1, 72.4 mg Kg¬-1 and 58.6 mg Kg¬-1 for benzene, toluene, ethylbenzene and xylenes, respectively. These values are in agreement with the 2005 CETESB guiding values for soil, except for benzene that is above the allowed value. For each type of soil, it was needed to build calibration models because soil composition affects the determination of hydrocarbons. The developed method is promising and may be used as a screening method to determine the occurrence of contamination in soils by BTEX / Doutorado / Quimica Analitica / Doutora em Ciências

The Mulden-Rigolen system, a new urban stormwater management system implemented in Germany, has been examined in this study. The aim of this new system is to replace traditional sewer system for urban road runoff, by infiltrating the incoming water locally through a dual underground system: an active top soil layer and a deeper trench of packed gravel. For each site using this system, the characteristics of the soils in terms of pH, texture, organic matter, infiltration rate as well as Heavy Metals (Cd, Cr, Cu, Pb, Zn) and Phosphorus soil concentrations were successfully determined. The measured values for the soil characteristics were still, after an operation time of up to 15 years for some sites, globally in the range of the recommendation of the German Association for Water, Wastewater and Waste, except for organic matter in some sites, suggesting the need for a more cautious maintenance. Concerning heavy metals and phosphorus content, no alarming soil contamination was observed indicating that the studied “Mulden-Rigolen” systems were still acceptable in terms of soil pollution after several years of use, according to the Danish standards. If this system seemed to have a good flexibility and adaptability to different urban land uses, its treatment efficiency still has to be fully assessed. Indeed, only a primary evaluation of its performance war carried out through a simplistic model which brought up some questions about pollutant retention (especially in case of Zn). Further research (intact soil columns experiments, sequential extractions, on-site runoff sampling) would be necessary to fully determine how well this system works in terms of water treatment.

Thesis (PhD)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Species differ in their sensitivities to toxicants and these differences are exploited in ecological risk assessment methods such as species sensitivity distributions (SSDs). The most commonly used endpoints for ecotoxicity testing and thus to generate data for use in SSDs are on the whole-organismal level, and usually include the evaluation of survival and reproduction. However, suborganismal biomarker responses are in many instances more sensitive than these whole-organismal responses. Therefore, this study investigated and compared responses on various biological organisational levels to determine their suitability for use in SSDs. Five terrestrial oligochaete species (earthworms) were selected as model test organisms, and were exposed to a range of concentrations of a well-studied pesticide, copper oxychloride. The investigated responses included survival, biomass change and reproduction on the whole-organismal level. In order to investigate responses on the suborganismal level, cells (coelomocytes) were extracted non-invasively. The spectrophotometric neutral red retention (NRR) assay was used to determine cell survival and the MTT assay to determine mitochondrial metabolic activity of the coelomocytes. The alkaline single cell gel electrophoresis (comet) assay was used to assess DNA integrity in these cells. The amount of Cu taken up by earthworms was also determined and compared to their responses. Species differences were observed in all responses, and EC50 and EC10 values were calculated for the whole-organismal endpoints and used to generate SSDs. From these SSDs, the hazardous concentrations where 5% of all species would be detrimentally affected (HC5) were calculated, which indicated that the most sensitive whole-organismal endpoint was mass change, followed by reproduction and survival. It was found that earthworms avoided feeding on the contaminated substrate in high copper oxychloride concentration exposures. The concentration where this behaviour occurred could be estimated for each species, and an SSD was constructed with these data. The HC5 value indicated that this response is more sensitive than earthworm survival, but less sensitive than the other responses. It was shown that the earthworms regulated their body Cu concentrations in a species-specific manner. This regulation of Cu was reflected in the suborganismal responses, and the species that had taken up the highest amount of Cu was the most sensitive species for all three suborganismal assays. Due to this regulation of Cu, the resulting dose-responses for the suborganismal endpoints did not allow for the calculation of EC50 values in most of the species and such data could thus not be used to generate SSDs. Sufficient EC10 values were however generated to construct SSDs from the results of the NRR and comet assays. The HC5 values obtained from SSDs constructed with EC10 values for both suborganismal and whole-organismal endpoints indicated that the NRR assay was the most sensitive endpoint, followed by both the comet assay and earthworm mass change, and subsequently the other whole-organismal endpoints. In conclusion, the majority of the responses on the various levels of biological organisation investigated during the present study were shown to be suitable to determine species sensitivity relationships in the terrestrial oligochaete species studied. / AFRIKAANSE OPSOMMING: Spesies verskil van mekaar ten opsigte van hulle sensitiwiteit vir toksikante, en hierdie verskille word in ekologiese risikobepalingsmetodes soos spesie-sensitiwiteitsverspreidings (SSVs) gebruik. Die mees algemene eindpunte vir ekotoksisiteitstoetse, en wat dus gebruik word om data te genereer vir SSVs, is op die heelorganismevlak, en sluit gewoonlik die bepaling van oorlewing en voortplanting van die toetsorganismes in. Hierdie eindpunte is egter in die meeste gevalle minder sensitief as suborganismiese biomerker-response. Hierdie studie het dus die response op verskeie vlakke van biologiese organisasie ondersoek en vergelyk om te bepaal of hulle geskik is vir gebruik in SSVs. Vyf terrestriële spesies van die klas Oligochaeta is gekies as toetsorganismes en is blootgestel aan 'n reeks konsentrasies van die goed bestudeerde pestisied koperoksichloried. Die response oorlewing, massaverandering en voortplanting is op die heelorganismevlak ondersoek. Vir die suborganismiese response is selle (selomosiete) met behulp van 'n nie-ingrypende proses vanuit die erdwurms geïsoleer. Die suborganismese toetse wat op hierdie selle gedoen is, was die neutraalrooi-retensietoets (NRR toets) om sel-oorlewing te bepaal, die MTT toets om mitochondriese metabolisme te bepaal en die alkaliese komeettoets om DNS-integriteit te bepaal. Die hoeveelheid Cu wat die erdwurms opgeneem het, is ook bepaal en met hulle response vergelyk. Verskille is tussen die spesies waargeneem vir al die response. Beide EK50 en EK10 waardes is bereken vir die heelorganismiese eindpunte om SSVs te genereer. Vanaf hierdie SSVs kon die gevaarlike konsenstrasie, waar 5% van alle spesies nadelig beïnvloed kan word (GK5), bereken word. Hierdie GK5 waardes het aangedui dat massaverandering die mees sensitiewe heelorganismiese eindpunt was, gevolg deur voortplanting en oorlewing. Die erdwurms het opgehou vreet aan die gekontamineerde substraat by hoë koperoskichloriedkonsentrasies. Die konsentrasie waar hierdie gedrag plaasgevind het kon vir elke spesie vasgestel word, en 'n SSV is met behulp van hierdie data genereer. Hierdie GK5 waarde het aangedui dat hierdie respons meer sensitief was as oorlewing, maar minder sensitief as die ander response. Die erdwurms kon die konsentrasie van Cu in hulle liggame op 'n spesie-spesifieke manier reguleer. Hierdie regulering van interne Cu is weerspieël in die suborganismiese response, waar die spesie wat die meeste Cu opgeneem het, ook die mees sensitiewe was vir al drie suborganismiese toetse. As gevolg van hierdie regulering van Cu en die gevolglike dosis-responsverhoudings, kon EK50-waardes nie vir al die spesies bereken word nie, en dus was daar geen EK50-data beskikbaar om SSVs mee te genereer nie. Genoegsame EK10 waardes kon egter bereken word vir die NRR- en komeettoetse, en gebruik word om SSVs te genereer. Die GK5-waardes wat bereken kon word vanuit die SSVs met EK10 waardes vir beide suborganismese en heelorganismiese response, het aangedui dat die mees sensitiewe eindpunt die NRR toets was, gevolg deur beide die komeettoets en massaverandering van erdwurms, en daarna die ander heelorganismiese eindpunte. Die gevolgtrekking is dat daar aangetoon kon word dat die meerderheid van die response wat gedurende hierdie studie ondersoek is, geskik is om sensitwiteitsverhoudings van hierdie groep spesies te bepaal.

Crude oil is of economic importance to any nation. However its poor management and disposal method has resulted in oil spillage and ground contamination. Most emphasis on crude oil contamination on the environment has been on surface and ground water pollution, as well as plants and animals with little or no attention paid to the engineering properties of the contaminated soil. This research is thus aimed at investigating the effect of light crude oil contamination on the geotechnical properties of kaolinite clay soil. This research is a laboratory based experiment in which the contaminated soil was prepared by adding different percentages of light crude oil (2%, 5%, 8%, 10%, 15% and 20%) measured by weight of the dry soil sample and mixed until a uniform mixture was obtained. The British Standard Test Methods for Civil Engineering purposes BS 1377: 1990 (EUROCODE 7: EN 1997: 2-5) was adopted with few modifications. The calculations were based on the fact that the pore space in the contaminated soil is occupied by water and crude oil so water content was calculated from the fluid content and the rate of evaporation of crude oil during oven drying was also considered. The classification results showed that crude oil contamination caused an increase in linear shrinkage, liquid limit, plastic limit and plasticity index between 0% to 20% contaminations. The compaction result showed that there was an increase in maximum dry density while the optimum moisture content decreased between 0% and 15% of crude oil contamination. The result showed that the soil could not compact at 20% contamination and above. Also, the coefficient of permeability increased with increase in the percentage of crude oil contamination while the coefficient of consolidation value (Cv) increases with increase in the percentage of contamination. There was a decrease in the cohesion value and the frictional angle due to the introduction of the crude oil into the soil. Although crude oil altered the geotechnical properties of the kaolinite clay soil and reduced its strength, the soil can still be used for geotechnical purposed after remediation.

A preocupação com a contaminação por metais reflete na busca de metodologias de recuperação de solos. O objetivo deste trabalho foi compreender os mecanismos de formação e oxidação dos sulfetos em solos e propor uma metodologia de imobilização de metais pela formação de sulfeto insolúvel e posterior fitoextração. Três experimentos foram conduzidos em solos contaminados com Cd e Zn. O primeiro teve como objetivo definir a concentração de (NH4)2S necessária para a formação dos sulfetos metálicos. Os resultados confirmam que a adição de sulfeto reduz a disponibilidade de Cd e Zn em Argissolos Vermelho-Amarelos distróficos e que concentrações de sulfetos superiores a 30 e 60 mmol kg-1, respectivamente para Cd e Zn, não melhora a capacidade de imobilização dos metais. O segundo experimento objetivou avaliar a influência da matéria orgânica, pH, tempo e ambiente na imobilização de Cd e Zn associado ao sulfeto. Foi demonstrado que a adição de matéria orgânica reduz a concentração de Cd solúvel e mantém o pH em faixa adequada às plantas. Para o Zn, a matéria orgânica não apresentou efeito significativo, prevalecendo o efeito do sulfeto. O aumento do pH, através da adição de carbonatos aumenta a imobilização do Cd e Zn em presença de sulfeto, influenciado pela formação dos respectivos hidróxidos. A exposição dos sulfetos metálicos a um ambiente oxidante reduz a imobilização de Cd e Zn devido à sua oxidação e consequente dissociação molecular. O terceiro experimento, desenvolvido em casa de vegetação, avaliou a disponibilidade de Cd e Zn e sua toxidez em Phaseolus vulgaris L. (feijão), utilizando a melhor dose de sulfeto com adição de matéria orgânica para obter maior eficiência na imobilização. A produção de massa seca da planta foi superior em solos que não continham sulfeto, o que indica fitotoxicidade. Concluímos que soluções de sulfeto podem ser utilizadas para imobilização temporária de Cd e Zn em solos contaminados, entretanto sua aplicação combinada à fitorremediação necessita de maiores estudos / The development of remediation of soil degraded areas methodologies reflects the concern with the metal contamination. The aim of this work was to understand the formation mechanisms and oxidation of sulfides in soils and propose a metal immobilization procedure by precipitation an insoluble sulfide and subsequent phytoextraction. Three experiments were conducted in contaminated soils with Cd and Zn. The first aimed to determine the (NH4)2S concentration necessary for the metallic sulfide formation. The results confirm that the sulfide addition reduces the Cd and Zn available in red-yellow dystrophic Argisoil and sulfide concentration above 30 and 60 mmol kg-1, respectively for Cd and Zn, not improve the metals immobilizations. The second experiment evaluated the organic matter, pH, time and atmosphere influence in the Cd- and Zn-sulfide immobilization. The addition of organic matter reduces the concentration of soluble Cd and maintaining the pH in adequate range for plants. For Zn, organic matter didn\'t show significant effect, prevailing the sulfide effect. The increase in pH by carbonates addition increases the Cd and Zn immobilizations in the sulfide presence. The exposure of metallic sulfide to an oxidizing atmosphere reduces Cd and Zn immobilization. The third experiment, developed in greenhouse, evaluated the Cd e Zn toxicity in Phaseolus vulgaris L. (bean) by using the best sulfide dose and addition of organic matter. The dry matter production was higher in soils without sulfide, indication phytotoxicity. We conclude that sulfide solutions can be used for Cd and Zn temporary immobilization in contaminated soils, however the application combined with phytoremediation needs further studies

Contaminated land is a widespread, global issue affecting millions of people. Atrazine is a commonly used herbicide which often contaminates groundwater and drinking water supplies and is associated with adverse health outcomes. Biochar is the solid product of pyrolysis and is associated with several environmental benefits. It may be an effective remediation tool when used as a soil amendment. This thesis investigates the mechanisms through which biochar can immobilise atrazine, and the implications of the mechanisms for remediating contaminated land. Nine biochar samples were obtained from the United Kingdom Biochar Research Centre , which were produced from softwood pellets (SWP), wheat straw pellets (WSP), miscanthus straw pellets (MSP), rice husk (RH) and oil seed rape (OSR) each at pyrolysis temperatures of 550°C and 700°C (excluding OSR at 700°C). The sorption mechanisms controlling atrazine sorption to these biochars were determined through various characterisation methods and batch sorption experiments. The sorption tests showed that sorption to each of the standard biochars occurs via multiple simultaneously occurring mechanisms, which are each promoted under certain conditions. Studies investigating sorption kinetics, isotherms and interactions with humic acids showed that for all biochars in this study, pore filling was a significant process through which atrazine is transported to adsorption sites, although poor intraparticle diffusion for softwood and oil seed rape biochars can prevent efficient transport. Wheat straw and rice husk biochars showed effective pore diffusion, resulting in high sorption capacities. Partitioning was associated with poor remediation outcomes and was significant to softwood biochars, although adsorption dominated overall sorption for all other biochars. pH was shown to significantly influence the occurrence of various sorption mechanisms. At low pH values, most biochars showed evidence of electrostatic repulsion between positive atrazine species and the positively charged biochar surface. At intermediate pH values, all biochars showed strong hydrogen bonding between H+ groups on the surface of the biochar and atrazine. A meta-analysis of previous relevant studies provided further evidence for hydrogen bonding of atrazine to biochar and showed that hydrophobic effects likely play little role in adsorption after accounting for the effects of surface area. Varying contributions of π-π EDA interactions, hydrogen bonding involving biochar O- groups, and interactions with ash minerals resulted in different sorption profiles for each biochar at high pH values. In order to further determine the mechanisms controlling sorption at high pH, surface compositions of SWP550, RH700 and OSR550 biochars were modified using hydrofluoric acid. Modification with hydrofluoric acid successfully removed the ash contents of rice husk and oil seed rape biochars and reduced atrazine removal at high pH values. This suggested that the ash fraction increases atrazine removal at high pH through complexation or catalytic hydrolysis. The roles of the various mechanisms are related to remediation outcomes in a novel manner allowing for the improved design of biochar for environmental remediation.