Reclamation success is highly dependent upon final soil quality of stockpiled soils, such as those found Cold Lake Oil Sands Region. Stockpiled soils, however, are generally poor in quality. Soils were amended with, biochar (BC), humalite (HU), a sub-bituminous coal; and peat (PT), as well as 50:50 blends of biochar:humalite (BCH) and biochar:peat (BCP). These amendments were applied at rates of 0, 6.55, 13.1 and 26.2 g C kg-1 each. Biochar, PT, and BCP applied at the rate of 26.2 g C kg-1 were found to reduce N2O emissions by 34, 54, and 70%, respectively, relative to the control. Within the bioassay, BC and PT amendment resulted in a 38 and 40% increase in dry matter yield (DMY) respectively. Finally, amendment typically resulted in significant net decreases in Olsen P values, while nitrate and ammonium concentrations were high in PT amended soils. In general, PT had the best overall performance. / October 2015

This research addresses the potential ecotoxicity of two emerging carbonaceous materials: C 60 and biochar. The use of these materials is rapidly increasing, as well as their potential for widespread applications. Thus, information about unintended consequences associated the widespread use, incidental or accidental release, and disposal of these emerging materials is needed. The environmental impacts of C 60 , its stable water suspension (nC 60 ), and biochar are assessed here using bacteria and earthworms as model receptors. The antibacterial activity of nC 60 can be mitigated by the presence of natural organic matter as a soil constituent or dissolved in the water column. Sorption to soil might decrease the bioavailability of nC 60 and thus its toxicity to bacteria. Aqueous organic matter also may mitigate nC 60 toxicity. Pristine C 60 showed toxicity to the earthworm's reproduction and was rapidly bioaccumulated by earthworms, although to a lower extent than smaller phenanthrene molecules that are more hydrophobic; thus, the large molecular size of C 60 hinders its bioaccumulation. Less bioaccumulation occurred at higher C 60 concentration in soil, which is counterintuitive and reflects that higher C 60 concentrations that exceed the soil sorption capacity exist as larger precipitates that are less bioavailable. Earthworms avoided soils amended with high concentrations of dry biochar, and experienced significant weight loss after 28-day exposure. The avoidance response was likely to avert desiccation rather than to avoid potential toxicants (i.e., PAHs formed during biochar production by pyrolysis) or nutrient scarcity. By wetting the biochar to field capacity before exposing the worms, this adverse effect can be completely mitigated. Overall, this research provides a foundation for ecotoxicity assessment associated with exposure to C 60 or biochar, and establishes a method by which other emerging materials can be evaluated for their potential environmental impacts.

Dans le cadre de cette recherche, la production de biocharbon par pyrolyse est étudiée à des conditions visant sa valorisation comme biochar (amendement pour le sol), tout en considérant son potentiel comme charbon vert (pour bioénergie ou transformations subséquentes). La production du charbon de biomasse s'est effectuée à l'aide de deux réacteurs à lits fixes de types batch, d'une capacité de 1 et 25 gb.hlbatch, respectivement. Le panic érigé (Panicum virgatum) est la biomasse lignocellulosique qui a été utilisée dans le cadre des tests. Les facteurs de production étudiés sont principalement la température (300, 400 et 500 °C) pour un court temps de résidence en réacteur (2,5 et 5 min) et l'effet de l'usage du CO2 plutôt qu'un environnement plus conventionnel d'azote. L'effet de ces facteurs est étudié par rapport aux caractéristiques physico-chimiques des biocharbons obtenus. Un suivi des produits pyrolytiques complémentaires (bio-huile et gaz) a aussi été effectué. Des extractions de biocharbon par Soxhlet (à l'aide de dichlorométhane) ont été analysées par GC-MS et ont permis l'identification d'une multitude de produits présents dans les biocharbons. Les conditions spécifiques utilisées pour la pyrolyse, entre autres la convection forcée avec taux de chauffe rapide à 300 °C — N2 à l'aide du réacteur 1 glbatch, ont présenté des rendements et propriétés de biocharbon avantageux pour l'amélioration de la productivité du procédé de torréfaction (en comparaison avec des travaux rapportés, notamment ceux de Gilbert et al. [2009]). Les analyses des extractions de charbons de biomasse ainsi que des bio-huiles (par GC-MS), produites à l'aide du réacteur 25g/batch, ont permis d'observer des différences significatives dans les composés obtenus lors de l'usage de CO2 vs N2. Plusieurs composés observés dans les extraits de biocharbons, produits en atmosphère de N2, se retrouvent en quantités moindres dans les extraits de biocharbons produits en atmosphère de CO2 pour des températures communes. À titre d'exemple, le furfural, un composé aromatique commun provenant de la dégradation des glucides, s'est retrouvé uniquement dans les extraits de biocharbons en présence de N2 vs CO2, à 400 °C. Parmi l'ensemble des conditions étudiées (pour les 2 réacteurs), uniquement le naphtalène et des dérivés du naphtalène sont observés comme hydrocarbures aromatiques polycycliques, et ce, uniquement suivant les traitements à 500 °C. L'étude de l'usage du CO2 comme gaz d'entrée en réacteur mena à des différences significatives pour l'ensemble des températures étudiées, et ce, tant pour les biocharbons que pour les produits liquides et gazeux. À 300 °C, en environnement de CO2 comparé à N2, il est possible d'observer une production de bio-huile significativement plus faible (18,0 vs 24,6 %; CO2 vs N2 pour P<0,002), ce qui représente un résultat cohérent avec l'obtention de biocharbon au contenu en composés volatils significativement plus élevé obtenu aux mêmes conditions (0,29 vs 0,35 g composés volatils - biocharbotig biomasse originale; CO2 vs N2 pour P=0, I ). De plus, à 500 °C, un contenu en cendres de biocharbon significativement plus faible a été observé en environnement de CO2 vs N2 (P<0,06). [symboles non conformes]

While the extent of grasslands in Southern Ontario has been greatly reduced, urban and suburban areas provide numerous potential sites for their restoration. Grassland restoration in cities can provide ecological and cultural benefits, but soil conditions may be less than optimal for native species recovery. This thesis explores the use of soil amendments in order to address nutrient deficiency on old-field meadow restoration sites. Five treatments were tested, namely the addition of (1) nitrogenous fertilizer, (2) native legume species, (3) biochar, (4) a combination of the previous three, and (5) an unaltered control. Each treatment was replicated four times on two different test plots in Waterloo Region, Ontario, Canada (Huron Natural Area and Springbank Farm), for a total of 40 subplots. The experimental plots were tilled in the fall of 2011, a randomly selected treatment was applied to each subplot, and then all were seeded with a mix of five native meadow species (2 grass, 2 forb, 1 sedge). Soil samples were taken from each subplot both before treatment application and also at the end of the growing season in 2012, and tested for nutrient levels (N, P, K), pH and organic matter. Species richness, as well as soil temperature and moisture, were regularly monitored over the growing season. In the fall of 2012, above-ground vegetation was harvested to assess accrued biomass. In order to detect differences in means, results were tested using one-way and repeated-measures ANOVAs, where appropriate. Pearson???s product-moment correlations were also employed to test for linear dependence between variables. There were no significant differences between treatments in terms of soil nutrients or pH at either site. At Huron Natural Area, post-treatment biochar-treated subplots had slightly higher levels of organic matter than controls (p=0.095). Values for species richness, above-ground biomass, soil temperature and soil moisture did not vary significantly between treatments. Species richness at Huron Natural Area was positively correlated with 2011 N (r=0.42; p=0.07) and organic matter (r=0.52; p=0.02) levels, while at Springbank Farm it was negatively correlated with 2012 N levels (r=-0.67; p<0.001). Above-ground biomass at Huron Natural Area was positively correlated with 2011 and 2012 P levels (both r=0.52; p=0.02), while at Springbank Farm it was positively correlated with 2011 N, P, K and organic matter, and 2012 N, P and K (all r>0.44; p<0.05). At Huron Natural Area, above-ground biomass was negatively correlated with soil temperature (r=-0.64; p<0.0001) and positively correlated with soil moisture (r=0.38; p=0.1). This study uncovered a strong, but variable, relationship between N concentration and species richness in old-field meadows. Furthermore, productivity was tightly correlated with different soil nutrient concentrations at each study site. The results demonstrate the need for restoration approaches to address local soil conditions on order to be effective. To date, there have been very few studies on meadow restoration, particularly in North America. More, and longer-term, multivariate studies are needed in order to test the effectiveness of different techniques.

This project examines the efficiency of a biochar-producing stove in meeting the needs of households in rural of Kenya. The stove has been tested and evaluated by five household in Embu, Kenya and compared with two other common cooking methods. The main parameters were time consumption, fuel consumption and emissions of carbon monoxide and particulate matter. Usability and energy use efficiency have also been evaluated. Three potential feedstocks have been examined for use in the biochar-producing stove; Grevillea prunings, maize cobs and coconut husks. The biochar-producing stove was well received by the households. It has potential of saving time, it saves fuel and it has a significantly lower level of emissions than other examined stoves. Despite some challenges related to the usability and the handling of the stove, an implementation of the biochar-producing stove can contribute to an alleviation of the women’s burdens, save fuel and contribute to a healthier indoor air climate.

For widespread use of biochar in agriculture and horticulture, it must be ensured that application will neither adversely affect soil and plants, nor exceed legislated contaminant concentrations. The most relevant groups of contaminants in biochar are potentially toxic elements (PTEs), polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOC). In this thesis, the concentrations of these groups of contaminants were analysed in 90 different biochars produced by slow pyrolysis. Subsequently, the concentrations were compared to legislation/guideline threshold values and linked to production conditions. The risk these contaminants pose to plant growth was also assessed, to give recommendations on production of safe biochar. PTEs can neither be formed nor destroyed, which means their presence in biochar is predominantly determined by feedstock type. However, significant levels of Cr, Fe and Ni were introduced into biochar from the furnace steel, whilst PTEs with low boiling points, such as As, Cd and Zn, partially evaporated during pyrolysis. PTEs were not responsible for phytotoxic effects observed for PTE-rich biochars despite biochar’s exceedance of available and total PTE threshold values for soil and soil amendments. Although initial tests were promising, the risk that PTE-rich biochars as amendment for soil and growing media pose, needs further investigation. The PAH concentration in biochar was markedly reduced by increasing carrier gas flow rate, and the type of feedstock also influenced the PAH content. However, there was no clear dependence of pyrolysis temperature on PAH concentrations, which was attributed to PAHs being increasingly formed and evaporated at higher pyrolysis temperatures. Ultimately, condensation of pyrolysis vapours and deposition on biochar was identified as the main risk for biochar contamination with PAHs, as this resulted in elevated concentrations of high-risk, higher molecular weight PAHs. Weaknesses in the pyrolysis unit design, such as cold zones, resulted in elevated concentrations of VOCs, as well as PAHs, in biochar. Comparing concentrations and phytotoxic potential of both compound groups, it was concluded that observed toxic effects were much more likely caused by VOCs in biochars containing both contaminants. Overall, formation of VOCs and PAHs cannot be prevented, but their presence in biochar resulting from retention and deposition can be minimised.

Methane is a potent greenhouse gas with a global warming potential 21 times that of carbon dioxide. Globally, ruminants are the main anthropogenic contributors to methane release to the atmosphere. Methane is produced in the gastrointestinal tract of ruminants, mostly within the rumen by methanogenic archaea. However, methane production represents a loss of 2 to 12% of dietary gross energy for the animal, which could otherwise be available for growth or milk production. Therefore, mitigation of methane production by ruminants could produce both economic and environmental benefits, with more sustainable and energy efficient livestock, and offering a promising way of slowing global warming. Despite extensive research undertaken to find ways of reducing methane emissions from ruminants, progress has been relatively limited. Furthermore, there is still a lack of studies linking rumen microbiology and ruminant nutrition and production. The central purpose of this research was to investigate feed additives to reduce methane emissions and to understand associated changes that occur in the rumen microbiota. For the first experiment (Chapter 2), biochar was evaluated as an antimethanogenic compound for beef cattle. The in vitro gas production technique was used to study the effects of biochar on rumen fermentation and methane production. Overall, methane production was reduced by 5% by the addition of biochar compounds (10 g/kg of substrate). The observed reduction in methane produced was not associated with a change in volatile fatty acid profile suggesting biochar primarily inhibited fermentation. Ammonia concentration was significantly reduced with biochar inclusion. Because different biochars had different effects on methane production, further investigation of relationships between the physicochemical properties of biochars and antimethanogenic effects are necessary. However, due to the small reduction in methane production recorded, research with biochar was discontinued. Encapsulated nitrate was then explored as an antimethanogenic additive and as an alternative non-protein nitrogen source to urea (Chapter 3). The effect of using encapsulated nitrate as a replacement for urea or dietary protein, plus the addition of inorganic sulphur, on enteric methane emissions, nutrient digestibility, nitrogen utilization and microbial protein synthesis from crossbred beef steers were studied. In addition, nitrate toxicity and eating behaviour were investigated. The inclusion of encapsulated nitrate reduced methane production compared to urea and a true protein source, with no adverse effects on rumen fermentation or nitrogen metabolism and no effects with the inclusion of elemental sulphur. The level of addition of encapsulated nitrate (14.3 g nitrate /kg DM) and the time of adaptation chosen for this study (14 days) were adequate to avoid nitrate toxicity. Finally, the effects of adding nitrate inclusion to different basal diets on rumen microbial populations and relationships of these populations with methane production were investigated (Chapter 4). The V4 hypervariable regions of the bacterial and archaea 16S rRNA genes were amplified and sequenced. Effects on microbial population induced by nitrate were dependant on the basal diet but nitrate altered specific archaeal and bacterial OTUs consistently between studies. A direct and strong correlation between some archaea taxonomic groups and OTUs with methane production was observed.

Submitted by ADEMIR RIBEIRO MENDONÇA null (33182912852) on 2018-02-08T15:21:57Z No. of bitstreams: 1 Dissertação de Ademir Ribeiro Mendonça.pdf: 1590154 bytes, checksum: b3e14a029c00dc98399df1a34c748eb1 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-02-09T12:42:32Z (GMT) No. of bitstreams: 1 mendonça_ar_me_jabo.pdf: 1590154 bytes, checksum: b3e14a029c00dc98399df1a34c748eb1 (MD5) / Made available in DSpace on 2018-02-09T12:42:32Z (GMT). No. of bitstreams: 1 mendonça_ar_me_jabo.pdf: 1590154 bytes, checksum: b3e14a029c00dc98399df1a34c748eb1 (MD5) Previous issue date: 2017-12-08 / Os resíduos de carvão vegetal podem ser utilizados de forma eficiente na agricultura, quando aplicados ao solo, em doses e granulometria adequadas exercem excelente desempenho aos vegetais. O trabalho foi realizado com o objetivo de estudar a interação entre doses e granulometrias de carvão vegetal de Eucalyptus citriodora em solo argiloso, na produção de cenoura híbrida de verão cultivar Mariana. O experimento foi conduzido em casa de vegetação na cidade de Bebedouro, SP. Com 16 tratamentos em esquema fatorial com 5x3+1, sendo 5 granulometrias (1 a 2 mm, 2 a 4 mm, 4 a 8 mm, 8 a 16 mm e 16 a 32 mm) combinadas com 3 doses (25, 50 e 75% em volume de carvão vegetal) mais controle (somente solo), com 4 repetições, em vasos de 8 litros dispostos num delineamento inteiramente ao acaso. Foi avaliada a retenção de água no início e final do ensaio, determinado o crescimento da parte aérea aos 30, 45, 60, 75 e 90 dias após emergência, bem como massa fresca e seca da raiz e parte aérea e dimensões das cenouras na colheita. Observou-se que o melhor desempenho das plantas ocorre na combinação de 50% (v/v) de carvão vegetal com a granulometria de 2 a 4 mm. No início do cultivo as plantas crescem melhor no solo, mas apresentam desempenho superior nos tratamentos com carvão vegetal a partir de 60 dias após emergência. / Charcoal wastes can be used efficiently in agriculture if well managed. With this purpose, this research aimed to study the interaction between dose and size of fine coal particles in clay soil, for carrot production. The experiment was conducted with 16 treatments in a 5x3 + 1 factorial scheme (5 granulometry: 1 to 2 mm, 2 to 4 mm, 4 to 8mm, 8 to 16 mm and 16 to 32 mm, combined with 3 doses:25 , 50% and 75% by volume of coal) plus control (soil only), with 4 replications. Each experimental unit was composed by a pot with 8 L capacity, and the assay was arranged in a completely randomized design. It were determined the water retention in the soil, the plants height measured at 30, 45, 60, 75 and 90 days after plants emergence, the fresh and dry mass of the root and plant shoot and the dimensions of the carrots at harvest. It has been observed that the best performance of the plants occurs in the combination of 50% (v/v) of coal with the fraction of 2 to 4 mm particle size. Plants at initial growth phases develop better in pure soil, however in the final growth phases shows superior performance in treatments containing charcoal.

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, 2015. / Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2015-04-01T14:30:05Z No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / Approved for entry into archive by Ruthléa Nascimento(ruthleanascimento@bce.unb.br) on 2015-04-17T19:06:37Z (GMT) No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / Made available in DSpace on 2015-04-17T19:06:37Z (GMT). No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / O biochar tem sido apresentado como uma alternativa viável para o uso agrícola do lodo de esgoto (LE) de forma sustentável. No entanto, ainda há dúvidas sobre os efeitos nutricionais do biochar em culturas de ciclo curto. O objetivo deste estudo foi avaliar o efeito de diferentes doses de biochar de LE nos componentes de fertilidade do solo e no desenvolvimento agronômico do rabanete, Raphanus sativus L. (Brassicae). O biochar de LE foi produzido com temperatura de pirólise de 300°C, a uma taxa média de aumento de temperatura de 11°C min-1, com um tempo de residência de 30 minutos. Um experimento foi instalado em casa de vegetação, cujo delineamento experimental utilizado foi o inteiramente casualizado com seis tratamentos e quatro repetições. Os tratamentos foram constituídos pelas seguintes doses de biochar, em Mg ha-1: 0,0 (controle); 20; 40; 60; 80; e 100. Foram avaliadas propriedades químicas do solo, antes e após o cultivo do rabanete. O desenvolvimento agronômico da cultura foi avaliado por meio das variáveis: número de folhas, altura da planta, comprimento foliar, massa seca da parte aérea e leitura SPAD. Foram avaliadas, ainda, as concentrações de nutrientes na planta e estimativa da produtividade. As variáveis testadas responderam ao aumento da dose do produto com as melhores respostas obtidas entre as doses de 20 e 60 Mg ha-1, sendo observada uma leve redução a partir da dose 60 Mg ha-1. Quanto às propriedades químicas do solo houve, de maneira geral, um enriquecimento dos nutrientes no solo com a aplicação do biochar. Esse aumento dos teores de nutrientes, principalmente fósforo e nitrogênio, e dos indicadores de fertilidade do solo se refletiram em maior concentração de nutrientes foliares, com respostas no maior desenvolvimento da planta. / Biochar has been presented as a viable alternative to the agricultural use of sewage sludge in a sustainable way. However, there are still doubts about the nutritional effects of biochar on short cycle crops. The objective of this study was to evaluate the effect of different doses of sewage sludge biochar on soil fertility components and agronomic development of the radish, Raphanus sativus L. (Brassicae). The sewage sludge was produced with biochar 300°C pyrolysis temperature at an average rate of temperature rise of 11°C min-1 with 30 minutes of residence time. One experiment was conducted in a greenhouse, whose experimental design was completely randomized with six treatments and four replications. The treatments consisted of the following doses of biochar in Mgha-1: 0.0 (control), 20, 40, 60, 80 and 100. Soil properties were evaluated before and after cultivation of radishes. The agronomic crop development was evaluated using the variables: number of leaves, plant height, leaf length, dry weight of shoot and index SPAD. Also the concentrations of nutrients in plant was evaluated and yield was estimated. The variables tested responded to the increase in dose of biochar 20 and 60 Mg ha-1, a slight decrease was observed from 60 Mg ha-1. On the chemical properties of the soil was, in general, an enrichment of nutrients in the soil with biochar application. This increase in nutrient levels, particularly phosphorus and nitrogen, and soil fertility indicators were suggested by a greater concentration of foliar nutrients, resulting in the further development of the plant.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-20T09:53:17Z No. of bitstreams: 2 Dissertação - Yuri Araújo Borges - 2015.pdf: 4286794 bytes, checksum: 6d681f97024291a4ebd8109488a88695 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-20T10:02:38Z (GMT) No. of bitstreams: 2 Dissertação - Yuri Araújo Borges - 2015.pdf: 4286794 bytes, checksum: 6d681f97024291a4ebd8109488a88695 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-20T10:02:38Z (GMT). No. of bitstreams: 2 Dissertação - Yuri Araújo Borges - 2015.pdf: 4286794 bytes, checksum: 6d681f97024291a4ebd8109488a88695 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-06-19 / (Sem resumo em outra língua) / Um meio eficiente para a manutenção da concentração de dióxido de carbono na atmosfera é a utilização do biocarvão na agricultura. Para utilizá-lo de forma correta em determinadas situações torna-se necessária à quantificação dos principais teores elementares nele contidos assim como na sua matéria-prima, a biomassa. Para quantificação de teores totais de carbono, nitrogênio, oxigênio e hidrogênio, a utilização das técnicas de calibração multivariada MLR e PLS associada aos métodos de seleção de variáveis SPA, GA e iPLS sobre espectros de infravermelho médio de amostras de biomassas e de seus biocarvões respectivos, resultaram na obtenção de modelos para a determinação de teores totais para esses elementos. Em diversas propostas foi obtido modelos viáveis para a quantificação dos teores elementares presentes nas amostras, com destaque a proposta SPA-MLR que apresentou sempre em todos os teores modelos com capacidade predição a outros conjuntos de amostras, com valores do parâmetro RPD de 4,152; 4,517; e 3,314 para carbono, oxigênio e hidrogênio, respectivamente. Além dos modelos multivariados também foram feitas análise de agrupamentos das amostras. Elas apresentaram padrões quando submetidas às análises PCA e HCA, havendo a separação de agrupamentos de amostras com relação direta às diferenças de porcentagem composicional de carbono e oxigênio, sendo esses os elementos com maior concentração nas amostras de biomassas e biocarvões e os mais sujeitos a mudança porcentual devido ao processo de pirólise.