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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.
31

Mykobiota šťovíku krmného / Mycobiota of energy sorrel

Janďourková, Hana January 2015 (has links)
Energy sorrel (Rumex patientia L. x Rumex tianschanicus A. Los.) is a plant with a high yield of above-ground biomass. Because of this, it is grown as energy crop, but in Ukraine it is also important forage crop. Mycobiota has not been examined, even though energy sorrel is grown in the Czech Republic experimentally since 1992 (in agricultural operations since 2001). The aims of this thesis were: to determine the composition of mycobiota of healthy plants and of mycobiota associated with leaf and stem spots, to verify whether fungi isolated from spots can cause these spots and if previously isolated fungus Phomopsis sp. can cause spots. Samples were colected from 4 sites in Czech republic, in three samplings during the vegetation season. Endophytes were isolated from root, stem and leaf. Fungi asociated with spots were isolated from stem and leaf. Fungi were cultivated on 2% malt extract agar and then morphologically determined. From representative strains were isolated DNA and sequences of the ITS region were compared with the GenBank databases, this verified the morphological determination and the sterile species were determined. The most common endophytes were Clonostachys rosea f. rosea, Cladosporium cladosporioides, Rhizopus arrhizus var. arrhizus, Alternaria alternata a Acremonium strictum...
32

Mykobiota šťovíku krmného / Mycobiota of energy sorrel

Janďourková, Hana January 2013 (has links)
Energy sorrel (Rumex patientia L. x Rumex tianschanicus A. Los.) is a plant with a high yield of above-ground biomass. Because of this, it is grown as energy crop, but in Ukraine it is also important forage crop. Mycobiota has not been examined, even though energy sorrel is grown in the Czech Republic experimentally since 1992 (in agricultural operations since 2001). The aims of this thesis were: to determine the composition of mycobiota of healthy plants and of mycobiota associated with leaf and stem spots, to verify whether fungi isolated from spots can cause these spots and if previously isolated fungus Phomopsis sp. can cause spots. Fungi were cultivated on 2% malt extract agar and then morphologically determined. From representative strains were isolated DNA and sequences of the ITS region were compared with the GenBank databases, this verified the morphological determination and the sterile species were determined. In total 24 morphotypes of endophytic fungi were cultivated from healthy plants. The most common species were: Clonostachys rosea f. rosea, Cladosporium cladosporioides, Rhizopus arrhizus var. arrhizus, Alternaria alternata and Acremonium strictum. From the spots were isolated in total 29 morphotypes, the dominant species were: A. strictum, Aureobasidium pullulans, C....
33

Drivkrafter och hinder ur ett multifunktionellt perspektiv : Förutsättningar och utvecklingsområden för produktion av biobränsle från våtmarker

Ljungberg, Stina January 2016 (has links)
Då Sverige redan nått flera av de energi- och klimatpolitiska målen kan målet om att skapa ett fossilfritt samhälle stå som ytterligare drivkraft för att fortsätta utvecklingen av de hållbara bränslena. Bidrag finns att få för att anlägga våtmarker, minska klimatpåverkan, förbättra naturmiljön och för utvecklandet av ny teknik samt bygga upp anläggningar för biobränsleproduktion. Trots detta har odling av våtmarksgrödor för energiutvinning ännu inte etablerats på energimarknaden. Denna studie är en del i kartläggningen av vad som kan komma att driva utvecklingen av våtmarker som källa till bioenergi framåt, och vilka delar som saknas i det arbetet. Efter intervjuer med intresserade och kunniga aktörer inom ämnet presenteras här de drivkrafter och hinder som påverkar denna utveckling. Drivkrafterna grundar sig i viljan att komma bort från fossila bränslen, att minska utsläppen av näringsämnen samt ge utrymme för biologisk mångfald, samtidigt som åtgärderna kan göra nytta för samhället och hjälpa till att nå klimat- och miljömålen. De största hindren utgörs av att speciella maskiner kan behövas för behandling av våtmarksgrödorna där terrängen är känslig och att mycket stora ytor skulle behövas för att öka lönsamheten. De ekonomiska stöd som finns att tillgå täcker inte heller alla nödvändiga steg i produktionsledet. Eftersom priserna på el och fossila bränslen är låga finns ännu ingen etablerad marknad för denna typ av energikälla och produktionen leder därför inte till någon större förtjänst. Biobränsleproducenter har även svårt att på ett tillräckligt effektivt sätt utvinna energin från grödorna. Detta gör att efterfrågan på energigrödor från våtmarker idag är mycket låg. Trots detta kan våtmarker bidra med en rad viktiga ekosystemtjänster i samband med produktion av energigrödor. Det rekommenderas därför att ett sådant system präglas av förvaltningsfilosofin mångbruk, där en naturresurs syfte är att nyttjas för flera ändamål samtidigt. Detta multifunktionella synsätt kan hjälpa till att öka våtmarkernas roll i uppfyllandet av flera av de nationella klimat- och miljömålen, om dess ekosystemtjänster vägs in tydligare i kalkylerna vid energiproduktion. / Sweden have already reached several of their goals for energy consumption, but the overall goal to become a fossil free society can still be seen as a driving force to keep developing renewable fuels. There is financial support for wetland construction, reduce impact on the climate, improve the natural environment, for developing new techniques and for biomass fuel plants. Still, cultivation of wetland crops for energy extraction are not yet well established on the energy market. After interviews with actors interested and knowledgeable in this field, this study presents driving forces and barriers affecting the development of this energy source. Driving forces comes from the ambition to move away from fossil fuels, decrease emissions of nutrients, make room for biodiversity, and provide services for the society while helping to reach climate and environmental goals. The barriers affecting this development is that special machines might be needed for handling of the crops and also to harvest the sensitive wetlands while large areas would be needed to increase profitability. The financial support available is not enough to cover the costs for production. Also, the prices on electricity and fossil fuels are low, which lowers the profitability for this type of energy source. Bioenergy producers have not yet found an effective way to extract energy from the crops. All of this makes the demand for energy crops from wetlands small. Despite this, wetlands provide several important ecosystem services and it is therefore recommended to use the management philosophy of multiple-use. With a multifunctional view of wetlands, the value of its ecosystem services can be added to the calculations of energy production and increase its role in reaching several national climate and environmental goals.
34

Adubação boratada na cultura do crambe em Latossolos / Fertilization borated in crambe culture in Latosols

Santos, Felipe Samways 19 January 2015 (has links)
Made available in DSpace on 2017-07-10T15:14:21Z (GMT). No. of bitstreams: 1 DissertacaoFelipeSSantos.pdf: 395247 bytes, checksum: 7d016fbdcf9f6acecdc4abbc60c2f279 (MD5) Previous issue date: 2015-01-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Crambe culture is emerging in the energy stage as a source of raw material for biodiesel production where the shortage of technical information related to culture hinders largescale production and therefore the consolidation of crambe in the energy stage. Therefore, this study is aimed at evaluating boron fertilization on crambe crop in two Latosols. The experiment was conducted in a greenhouse belonging to the Agronomic Institute of Paraná, in Santa Tereza do Oeste - PR. The treatments were arranged in a 2x3 factorial project in two soils with different textures (clayish and medium texture) and three doses of B (0, 1 and 8 mg kg-1) applied to the soil. The experimental design had randomized blocks with five repetitions. The experimental unit consisted of a vase containing 2.0 kg of soil with two crambe plants. We evaluated the plant height, dry matter production of roots, stem and fruits, number of fruits per plant, number of branches per plant, weight of one hundred grains and the leaf B content. The texture of the soil did not affect any variable evaluated. There was no significant interaction between the B doses applied and the soil texture. The plant height, number of branches per plant and dry mass of one hundred fruits were not affected by the boron fertilization. The number of fruits per plant and dry matter production of roots, stems and fruits were higher with the use of 1 mg kg-1 B in the soil. The higher the dose of B, the greater were the levels of this micronutrient in crambe leaves. The application of 8 mg kg-1 B caused visible toxicity symptoms in the crambe leaves. / A cultura do crambe desponta no cenário energético como uma fonte de matéria prima para a produção de biodiesel, onde a escassez de informações técnicas referentes à cultura dificulta a produção em larga escala e consequentemente a consolidação do crambe no cenário energético. Assim, com esse trabalho objetivou-se avaliar a adubação boratada na cultura do crambe em dois Latossolos. O experimento foi conduzido em casa de vegetação pertencente ao Instituto Agronômico do Paraná, no município de Santa Tereza do Oeste - PR. Os tratamentos foram dispostos em esquema fatorial 2x3, sendo dois solos com diferentes texturas (argiloso e textura média) e três doses de B (0, 1, e 8 mg kg-1) aplicadas no solo. O delineamento experimental foi o de blocos casualizados, com cinco repetições. A unidade experimental foi constituída por um vaso contendo 2,0 kg de solo com duas plantas de crambe. Foram avaliados a altura da planta, produção de matéria seca de raízes, caules e frutos, número de frutos por planta, número de ramos por planta, massa de cem grãos e teor foliar de B. A textura do solo não influenciou nenhuma variável avaliada. Não houve interação significativa entre as doses de B aplicadas e a textura do solo. A altura das plantas, número de ramos por planta e massa seca de cem frutos não foram influenciados pela adubação boratada. O número de frutos por planta, produção de massa seca de raízes, caule e frutos foram maiores com a aplicação de 1 mg kg-1 de B no solo. Quanto maior a dose de B, maiores foram os teores desse micronutriente nas folhas do crambe. A aplicação de 8 mg kg-1 de B provocou sintomas visuais de toxidez nas folhas de crambe.
35

Variabilidade espacial de atributos físicos e químicos de um Latossolo argiloso correlacionados ao rendimento de grãos da cultura do Crambe (Crambe abyssinica Hochst) / Spatial variability of physical and chemical attributes of a clayey oxisol correlated to grain yield of crop Crambe (Crambe abyssinica Hochst)

Vieira, Maycon Daniel 13 July 2011 (has links)
Made available in DSpace on 2017-07-10T15:14:46Z (GMT). No. of bitstreams: 1 Maycon Daniel Vieira.pdf: 992790 bytes, checksum: a5230812f9a9657de0339f5c1b656b1f (MD5) Previous issue date: 2011-07-13 / The objective of this study was to verify, with the help of thematic maps obtained by kriging, the existence of correlationship of physical and chemical attributes with the yield of crambe (Crambe abyssinica Hochst) in clayey Oxisol under no-tillage system. To this end, we conducted research in an experimental area in the city of Cascavel - Paraná - Brazil. The experimental grid was established in an area with dimensions of 100 x 100m, marked every 10m in two directions perpendicular to one another, totaling 100 points, samples were collected for bulk density and soil resistance to penetration depths of 0-0,1, 0,1-0,2 and 0,2-0,3m, partially deformed samples to determine soil pH, MO, P and K as well as samples for determining the yield of the crambe. Statistical analyzes were performed using the software R, and the geostatistical analysis was performed using the package GeoR. In developing the experimental semivariograms were used estimators Matheron and Cressie & Hawkins and adjustments of the theoretical semivariogram methods were used ordinary least squares and weighted least squares. Theoretical models have been adjusted and the spherical exponential, and the choice of the best model has been performed by means of cross-validation. The results showed a weak correlation between the thematic maps of physical and chemical properties of soil with the crop yield of crambe. The maps RSP1 and pH showed the highest correlation with yield. Chemical characteristics showed higher correlation with higher levels of productivity at pH ≥ 5,0, MO ≥ 5,5 m/v (%), P ≥ 15,0 mg dm-3 and K ≥ 0,4 cmolc dm-3. / O objetivo deste trabalho foi verificar, com auxílio de mapas temáticos obtidos através da interpolação por krigagem, a existência de correlação de atributos físicos e químicos com a produtividade da cultura do crambe (Crambe abyssinica Hochst) em Latossolo argiloso sob sistema de plantio direto. Para tanto, conduziu-se a pesquisa em área experimental localizada na cidade de Cascavel Paraná Brasil. O grid experimental foi estabelecido em área com dimensões de 100 x 100m, marcado a cada 10m em duas direções perpendiculares entre si, totalizando 100 pontos, onde foram coletadas amostras de densidade e resistência do solo à penetração nas profundidades de 0-0,1, 0,1-0,2 e 0,2-0,3m, amostras parcialmente deformadas do solo para determinar o pH, MO, P e K, bem como amostras para determinação da produtividade da cultura do crambe. As análises estatísticas foram realizadas com auxílio do software R, sendo que a análise geoestatística foi realizada utilizando o pacote GeoR. Para a elaboração dos semivariogramas experimentais foram utilizados os estimadores de Matheron e Cressie & Hawkins e para ajustes dos semivariogramas teóricos foram utilizados os métodos dos mínimos quadrados ordinários e mínimos quadrados ponderados. Os modelos teóricos ajustados foram o esférico e exponencial, sendo que a escolha do melhor modelo foi realizada por meio da validação cruzada. Os resultados mostraram que houve correlação fraca entre os mapas temáticos de atributos físicos e químicos do solo com o da produtividade da cultura do crambe. Os mapas RSP1 e pH foram os que apresentaram maior correlação com a produtividade. Os atributos químicos apresentaram maior correlação com melhores níveis de produtividade para valores de pH ≥ 5,0, MO ≥ 5,5 m/v (%), P ≥ 15,0 mg dm-3 e K ≥ 0,4 cmolc dm-3.
36

Economic analysis of potential Camelina oil crop supplies in the Northwest U.S.

Stein, Lukas (Lukas Colin) 14 September 2012 (has links)
The demand for biofuels continues to increase due in part to government standards and promotion as well as the ambitious goals set by various companies and industries. Camelina is considered to be an ideal energy crop because of its low input requirements, suitability for marginal soils, and naturally competitiveness with weeds. A partial equilibrium model with a break-even price approach is used to estimate the potential supply curves for Camelina in Idaho, Montana, Oregon, and Washington. The supply curves are used to determine if the 50 million gallon goal set by the "Farm to Fly" initiative can be met. Given the current price of Camelina, $0.15/lb, the estimated supply of Camelina in all 4 states is 1,756,076,887 lbs and 1,493,684 acres. This estimation assumes that if the wheat-Camelina rotation is more profitable than the current crop rotation, then all of the acres will be converted to a wheat-Camelina rotation. When a 5% adoption rate is applied to the low and the intermediate rainfall zones and a 1% to the high rainfall zones, the number of acres converted to Camelina decreases to 72,213. These results suggest that given current market conditions, the supply of Camelina in the Northwest is not enough to meet the biofuel goal without an increase in yield and government promotion. / Graduation date: 2013
37

Direct and multistep conversion of lignin to biofuels

Kosa, Matyas 30 August 2012 (has links)
Lignin is the second most abundant biopolymer on Earth, right after cellulose, with a highly complex chemical structure that hinders its possible utilizations. Applications that utilize lignin in different manners are of great interest, due to its inexpensive nature. Present work is based on the notion of converting lignin into different biofuels that have only a few, however important, advantages over lignin as a direct energy source. The first part of current work (pyrolysis) details the analysis of lignin from a relatively new lignin isolation process called LignoBoost. It is obtained from the pulp and paper industry via CO₂ precipitation of lignin from black liquor (BL). This method is environment friendly, results lignin with minimal oxidation, eliminates the main bottleneck of the Kraft cycle (recovery boiler capacity), and yet leaves enough lignin in the process stream to recover pulping chemicals and generate energy for the pulp mill. Pyrolysis had converted this lignin into bio-oil with high aliphatic content and low oxidation level, all advantageous for application as liquid fuel. The second part of this dissertation proved the theory that lignin degradation and lipid accumulation metabolic pathways can be interconnected. Gram-positive Rhodococcus opacus species, DSM 1069 and PD630 were used to evaluate lignin to lipid bioconversion, starting with ethanol organosolv and Kraft lignin. This conversion is a first step in a multistep process towards biodiesel production, which includes transesterification, after lipids are extracted from the cells. Results clearly indicated that the lignin to lipid bioconversion pathway is viable, by cells gaining up to 4 % of their weight in lipids, while growing solely on lignin as a carbon and energy source.
38

Ergebnisse mehrjähriger Sortenversuche Sorghumhirsen

Zander, Daniela 18 July 2012 (has links) (PDF)
Von 2005 bis 2011 wurden auf unterschiedlichen Versuchsstandorten in Deutschland die Trockenmasseerträge von Sorghumhirsesorten und Maissorten verglichen. Es stellte sich heraus, dass der Anbau von Sorghumhirsen auf allen geprüften Standorten mit Erfolg möglich ist und eine Alternative zum Mais im Energiefruchtfolgesystem darstellt. Die Sorghum bicolor-Sorten erreichen ein höheres Ertragspotenzial als die Hybridsorten (Sorghum bicolor x sudanense). Die Hybridsorten zeichnen sich durch eine schnellere Abreife aus und erreichen silierfähige Trockensubstanzgehalte. Verglichen mit Mais erzielen die Sorten der Sorghumart Sorghum bicolor insbesondere auf den D-Süd-Standorten gleiche oder bessere Erträge.
39

Sorghumhirsen - Sorten- und Anbauversuche

Jäkel, Kerstin, Zander, Daniela 19 November 2012 (has links) (PDF)
Ausgewertet wurde der Anbau von Sorghumhirsen auf Versuchsfeldern unterschiedlicher bodenklimatischer Bedingungen. Dabei variierten Versuchsparameter wie Bodenbearbeitung, Aussaattermin, Saatstärke, Reihenweite, Saattiefe und Unkrautregulierung. Für Sorghum bicolor wurde eine optimale Saatstärke von 25 und für die Sudangräser von 40 Körnern/m² ermittelt. Die Reihenweiten sind von untergeordneter Bedeutung, sodass die übliche Drillweite im Betrieb nicht verändert werden muss. Die Versuche zeigen, dass Sorghum sowohl als Drill-, Einzelkorndrillsaat als auch im Mulchsaatverfahren ausgebracht werden kann. Heft 24/2012 der Schriftenreihe des Landesamtes für Umwelt, Landwirtschaft und Geologie mit dem Titel „Ergebnisse mehrjähriger Sortenversuche Sorghumhirsen“ bilanziert die Trockenmasseerträge von Sorghumhirsesorten im Vergleich zu Mais.
40

Factors that affect the production and the distribution of biofuels products by rural farmers in Zimbabwe

Mukonza, Chipo. January 2014 (has links)
D. Tech. Business Administration / The study attempts to identify and quantify socio-economic factors that are influence the production and distribution of biofuels products in Zimbabwe. It also seeks to provide an empirical analysis of the importance of stakeholders in Biofuel production and distribution and how their perceptions and influences tend to affect production and distribution.

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