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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.
361

Energy and nutrient recovery from dairy manure : Process design and economic performance of a farm based system

Celander, Filip, Haglund, Johan January 2014 (has links)
This thesis assessed the technical and economic premises for installing systems that process manure in order to recover nutrients and inherent energy. The main purpose of recovering nutrients was to extract phosphorus from the manure, so as to be able to distribute more of the manure on the farm without exceeding the phosphorus regulation. Three other scenarios were included as reference; conventional manure handling, solid-liquid separation only and solid-liquid separation including energy recovery. Since most important parameters for modeling scenarios in agriculture are site-specific (e.g. soil type, crop rotation and manure composition), the thesis results were based on a case farm. The case farm is a 675 ha dairy farm with approx. 1400 milking cows, located in Östergötland, Sweden. As for the results, it was first concluded that the central characteristics of manure were the content of dry matter (DM), nitrogen (N), phosphorus (P) and potassium (K). The higher the DM content, the more fuel for energy recovery, and the higher the N:P-ratio, the more on-farm N can be utilized before having to consider the P regulation. The technical premises for farm-scale nutrient recovery were limited to commercial techniques from companies operating in Sweden, and included various possible processing methods, such as; pH modification, anaerobic digestion, coagulation-flocculation, precipitation, filtration and reverse osmosis. However, most methods were either too costly or simply not realistic to install on stand-alone farms, resulting in only two feasible options; struvite precipitation and secondary solid-liquid separation with a decanter centrifuge. The comparison in economic performance for all scenarios resulted as follows: nutrient recovery by struvite precipitation was the most profitable scenario of all, if struvite was allowed to replace mineral P fertilizer (i.e. end-product on-farm utilization). If not, it was more profitable to invest in only energy recovery, as nutrient recovery by secondary solid-liquid separation or struvite precipitation with end-product sales were not as profitable. However, the absolutely largest increase in profitability lies within investing in a primary solid-liquid separation. As for the case farm, this investment reduced costs by more than 2 MSEK, while any of the latter scenarios reduce costs by 0,1-0,2 MSEK. Furthermore, the possible utilization of the waste heat from energy recovery increased profitability by a factor of ten.
362

Assessment of environmental-livestock interactions in crop-livestock systems of central Ethiopian highlands

Nigatu Alemayehu Minase 09 1900 (has links)
The study was done in Adaa district which is one of the 12 districts in East Shoa zone in Oromia regional state of Ethiopia. It is located southeast of Addis Ababa at 38o51’ 43.63’’ to 39o04’ 58.59’’ E and 8o46’ 16.20’’ to 8o59’ 16.38’’ N, on the western margin of the Great East African Rift Valley. The altitude ranges from 1 500 to ≥ 2 000 meters above sea level. The district has a high potential for mixed livestock and crop production systems. The purpose of this study was to make up for the paucity of information on livestock and environment interaction by assessing the relationship of livestock, soil, water, land, climate and crops under mixed crop-livestock production systems in central Ethiopian highlands. The objectives of the study were: (a) to assess the effect of change in land management on carbon storage and the contribution of livestock to carbon storage; (b) to examine the impact of livestock on natural resources and the environment; (c) to assess the effects of the change in traditional agricultural practices, expansion of factories, slaughter houses, greenhouses and flower farms on water and soil quality; (d) to evaluate the effect of climate change on livestock production under small-scale agriculture; and (e) to recommend options for mitigation and adaptation to environmental changes. The research design was non-experimental and did not involve the manipulation of the situation, circumstances or experiences of the interviewees. The design was comparative research that compared two or more groups on one or more variables, such as the effect of agricultural land use management, tillage type etc. on carbon storage in the soil. This research also applied a longitudinal design that examined variables such as the performance exhibited by groups over time. Purposive sampling was often used to measure the effect of agricultural, industrial effluent and human interferences on the environment by measuring nutrient contents at sources in the soil, water and manure. Biological data were complemented by key socio-economic survey by interviewing individual farmers and focus groups from sampling sites. Secondary data were also reviewed to measure soil degradation and run-off attributed to livestock. Results showed that animal waste and farmyard manure had the highest contribution in the addition of carbon in the soil. This implied that for most of carbon inputs livestock products and by-products had a greater place in the carbon sink. Therefore, livestock production could be considered as one of the major agricultural production systems in soil carbon storage. Similarly, livestock production systems also play an important role in maintaining the eco-system balance through nutrient recycling. On the average, the number of livestock per household for most species increased during the Derge regime in the 1990s compared to the Haile Sellassie regime in the 1970s when people did not own land; and then the number declined in the 2000s except for equines, crossbreeds and oxen. The change to crop intensification led to the change in the purpose for livestock keeping. Farmers started keeping certain types of animals for specific purposes unlike before when livestock was kept for prestige and economic security. The major drive for the change of attitude towards the purpose of keeping livestock was scarcity of resources, mainly feed and water. Equine ownership has significantly increased due to their low off-take rate and their feeding habits which allowed them to survive in harsh environments where feed resources were extremely scarce. There was a significant difference in crop response to manure application. Vegetables produced higher yields with manure than chemical fertilizers. Cereals on the other hand responded more to chemical fertilizers than to manure. Therefore, combining manure and chemical fertilizers was the best option for the sustainability of crop production in the study area. Some of the limitations to the use of manure as an organic fertilizer were inadequate manure production, high labour cost, bulkiness and high cost of transport to the fields and weed infestation. Manure management systems in the study area were affected by livestock husbandry practices. Only crossbred cattle (5%) were zero-grazed and used; and manure was stored in pits as slurry. Indigenous cattle were grazed outdoors in the fields during the day and at night they were kept in kraals near homesteads. There was a substantial loss of nutrients during the day when animals were grazing in the fields through leaching and trampling of dung and urine patches. Indoor or zero grazing of livestock could reduce nutrient losses. The use of manure as fuel in the study area had no significant effect on CO2 emissions at household or local level, but had a negative impact on soil organic carbon storage and soil fertility. Therefore, for improved yield and balanced eco-systems manure burning has to be replaced by other alternative energy sources such as bio-gas and kerosene. The largest carbon equivalent emissions were from CH4 (72.6%), N2O (24%) and CO2 (3.4%) which indicated the need to improve livestock and manure management systems under smallholder agriculture. Overall, there was an indication of a decline in water resources on per capita basis. The major contributing factors were combined pressure of human and animal population on natural resources that led to excessive deforestation, loss of biological diversity, overgrazing, soil degradation and various forms of pollution and contamination. The global climate change also played a role in the decline in water resources due to the decrease in annual precipitation and increasing temperatures. Urbanization and economic growth increased the demand for milk and meat, which required additional water use for each unit of increased animal protein. The demand for milk and meat is expected to double in the next 20 years with an annual growth rate of between 2.5 to 4%. From the sixty-year meteorological data (1951-2009) there was an established increase in rainfall by 2% per annum; and maximum and minimum temperature by 0.08oC per decade, which amounted to a cumulative temperature increase of 0.5oC in the last decade. The increase in precipitation and temperature favoured the adaption of lowland crops like maize and sorghum to highland agro-ecology. Climate prediction models forecasted that most of the highlands in Ethiopia will remain suitable for cereals like wheat and Teff for the next 50 to100 years. However, the perception of farmers indicated that they felt more heat and warm weather than they have experienced before. They reported that rainfall is now more erratic or comes late and stops earlier before plants completed their vegetative growth. / Environmental Sciences / D. Litt. et Phil. (Environmental Science)
363

Sanjeevak as a source of nutrients and phytohormones for production and propagation of plants

Orendo-Smith, Richard 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The use of cowdung as an organic fertilizer in Asian and African agriculture is an ancient practice. This explains its renewed interest, partly due to the financial inability of most farmers to purchase agrochemicals but also the ever increasing need to adopt greener technologies that do not adversely affect soil health, water quality, biodiversity and promote sustained or even increased food production. In this context, many innovative farmers have developed their own novel technologies based on the use of local resources. One such innovation is Sanjeevak (a mix of cow dung, cow urine, water and a handful of sugar); which showed very promising boosting effect on crop productivity. However, very little scientific work has so far been conducted to evaluate its effect as an organic product for soil amendments. The present study was subdivided into three main objectives. (i) To assess the fertilizing value, human health and ecological risk profiles of Sanjeevak; (ii) To screen Sanjeevak for phytohormones content using Salkowski colorimetric method and liquid chromatography – mass spectrometry (LC-MS) (iii) To evaluate Sanjeevak application at various rates on growth parameters and yield of various crops cultivated in glasshouse and field conditions. Sanjeevak was assessed for its micro and macro nutrients contents. The analysis showed the presence of micronutrients such as Mg, Na, Ca and Zn at variable concentrations and phosphorus (P) (0.007%) and potassium (K) (0.063%). However, Sanjeevak content in total nitrogen (TN) (0.11%), and total organic carbon (TOC) (0.71%) was very low; suggesting that it may be a viable source of nutrients only if applied at higher and consistent rates or alternatively by improving its formulation. Also, Sanjeevak was analysed for its microbiological characteristics and level of heavy metals content in comparison to the strictest legislations that regulate the use and application of wastewater sludge to agricultural land in South Africa. The findings showed that heavy metals, which averaged from 0.03±0.01 for Arsenic (As) to 4.74±0.92 mg/kg for Zinc (Zn) and feacal coliform was estimated at 1.2×102 CFU/g dry matter measured were considerably below the threshold (for Arsenic between 40 to 75 mg/kg dry weight; for Zinc between 2800 to 7500 mg/kg dry weight) and faecal coliform bacteria between 1000 to 1×107 CFU/g dry weight for application as a source of soil amendments. Studies investigating the detection and concentration of phytohormones in Sanjeevak were carried out. In using the Salkowski colorimetric method to detect and quantify auxins from Sanjeevak and its composites (cow urine and dung), the results showed the presence of indole-3-acetic acid (IAA) at variable concentrations ranging from 20.38±2.1 ppm in cow urine, 20.1±6.6 ppm in cow dung, Sanjeevak 17.90±1.1 ppm to up to 138.31±12.6 ppm when LTRP was added to Sanjeevak bacterial cultures and by varying parameters such as incubaton time and temperature. Screening of the above mentioned samples for IAA using LC-MS analysis validated earlier findings. Further analysis of these results strongly emphasized the influence of bacteria in Sanjeevak in producing IAA. Trials were carried out both in the glasshouse and the field. In the greenhouse, different Sanjeevak application rates consistently confirmed its root promoting effect on crops such as tomato, cucumber and grapevine and increased wheat yield independent of the nutrients it contains. Marginal increases were recorded between treatments under field conditions; for example compost and compost + Sanjeevak 20.35 and 20.61 t/ha; and 2.46 and 2.60 t/ha compared to the control 11.67 t/ha and 1.29 t/ha respectively for tomato and maize. However, statistical analysis of the results obtained, revealed that there was no difference between treatments (control, compost, Sanjeevak and compost + Sanjeevak) for the same crop tested due to the high coefficient of variation of the data. Therefore, the use of Sanjeevak as an organic source of soil amendments may be considered as a cheaper alternative to effective microorganisms (EM) technology made up of local and natural resources. As observed in the study, it may be best used in combination with a reliable source of plant nutrients. / RESUMEE: L'utilisation des excréments de vaches comme engrais organique dans l'agriculture asiatique et africaine est une pratique très ancienne. Ceci explique son intérêt renouvelé, en partie due à aux restrictions monétaires de la plupart des agriculteurs d'acheter des produits agrochimiques, mais aussi la nécessité croissante d'adopter des technologies vertes qui ne nuissent pas à la qualité des sols, des eaux, la biodiversité et qui permettent d’améliorer la production agricole. C’est dans ce contexte que de nombreux paysans ont développé des techniques nouvelles dépendant des ressources naturelles et locales. L’utilisation de Sanjeevak (un mélange d’excréments de vaches, d’urine de vaches, l'eau et du sucre), a démontré sa capacité à accroître la productivité des plantes vivrières. Cependant, très peu de travaux scientifiques ont jusqu'à présent été menée pour étudier ce produit organique. La présente étude a été subdivisée en trois objectifs principaux. (i) Evaluation de la valeur fertilisante, et les profils de risques écologiques et sanitaires de Sanjeevak, (ii) Etudes de détection des phytohormones et leurs concentrations en utilisant une méthode colorimétrique adaptée de celle de Salkowski et la chromatographie liquide - spectrométrie de masse (LC-MS) (iii) Etude des effets de l’utilisation de Sanjeevak a différents taux d’applications sur la croissance et le développement des plants. Sanjeevak a été évaluée pour son contenu en micro et macro nutriments. L'analyse a montré la présence d'oligo-éléments tels que Mg, Na, Ca et Zn à des concentrations variables. De plus, son contenu en éléments majors tels que le phosphore (P) (0.007%), le potassium (K) (0.063%), l’azote (N) (0.11%), et carbone (C) (0.71%) est très faible; suggérant qu'il pourrait être une source viable de nutriments que si elle est appliquée à des taux plus élevés et répétés ou alternativement en améliorant sa formulation. En outre, Sanjeevak a été analysé pour ses caractéristiques microbiologiques et sa concentration en métaux lourds en comparaison a la législation qui réglemente l'utilisation et l'application de déchets liquide d’origines domestiques sur les terres agricoles en Afrique du Sud. Les résultats ont révélé que des métaux lourds et le niveau de coliformes fécaux mesuré était inférieur aux seuils d'application en tant que source d'amendements de sols agricoles. Les études portant sur la détection et la concentration d’hormones végétales ont été effectuées. En utilisant la méthode colorimétrique de Salkowski pour détecter et quantifier les auxines de Sanjeevak, les urines et les excréments de vaches; les résultats ont révélé la présence d'acide indole-3-acétique (AIA) à des concentrations variables dans les urines, les excréments et Sanjeevak. Une autre analyse des échantillons mentionnés ci-dessus pour les AIA en utilisant LC-MS a validé les résultats obtenus au préalable. L’étude détaillée de ces résultats confirme l'influence des micro-organismes dans la production des hormones végétales. Concernant les expériences sous serre, les différents taux d'application de Sanjeevak ont confirmé son effet stimulant à la croissance accélérée des racines des plantes telles que la tomate et les raisins et augmenté le rendement du blé indépendamment des nutriments qu'il contient. L'analyse statistique des résultats obtenus dans des conditions de terrain, a révélé qu'il n'y avait pas de différence entre les traitements (contrôle, compost, compost + Sanjeevak et Sanjeevak) pour la même plantes testées. Par conséquent, l'utilisation de Sanjeevak comme un produit organique qui améliore la qualité des sols et le rendement des cultures vivrières; peu être considéré comme un inoculum contenant des microorganismes constitué de ressources locales et naturelles. Comme l'a observé dans l'étude, il pourrait être mieux utilisé en combinaison avec une source fiable de nutriments végétaux. / AFRIKAANSE OPSOMMING: Die gebruik van beesmis as 'n organiese kunsmis in Asië en Afrika is' n eeu-oue landbou praktyk. Dit verklaar die hernude belangstelling, deels vanweë die finansiële onvermoë van meeste boere om landbouchemikalieë aan te koop, maar ook as gevolg van die toenemende behoefte vir groener tegnologie wat nie nadelig is vir grond gesondheid, waterkwaliteit, biodiversiteit en wat volhoubaarheid of selfs verhoogde voedselproduksie bevorder. In hierdie konteks het baie vindingryke boere hul eie nuwe tegnologie, gebaseer op die gebruik van plaaslik verkrygde hulpbronne, ontwikkel. `n Voorbeeld hiervan is Sanjeevak ('n mengsel van beesmis, beesurine, water en die handvol melasse), wat belowende bevorderende effekte op gewas produktiwiteit en grond mikroflora getoon het. Tot dusver was daar egter baie min wetenskaplike werk gedoen om die effek daarvan as 'n organiese produkte vir grond wysigings te evalueer. Hierdie studie was verdeel in vier belangrike doelwitte. (i) Om die bemestingswaarde, menslike gesondheid en ekologiese risiko-profiele van Sanjeevak te evalueer; (ii) Om Sanjeevak vir fitohormone inhoud en vlakke met behulp van 'n kolorimetriese metode afgelei van dié van Salkowski en vloeistofchromatografie – massaspektrometrie (LC-MS) te besigtig; (iii) Glashuis en veld waarneming reaksies met betrekking tot groei parameters en opbrengs van verskeie gewasse na die toediening van Sanjeevak by verskillende tempos; (iv) Laastens, om die effek van die Sanjeevak voorbehandeling op saad ontkieming en voortplanting te toets in vergelyking met die metodes en tegnieke wat gereeld gebruik word. Sanjeevak is geassesseer vir die mikro-en makro voedingstowwe inhoud. Die analise het die teenwoordigheid van mikrovoedingstowwe soos Mg, Na, Ca en Zn by wisselende konsentrasies, asook fosfor (P) (0.007%) en kalium (K) (0.063%), getoon. Sanjeevak inhoud van totale stikstof (TN) (0.11%), en die totale organiese koolstof (TOC) (0.71%) was egter baie laag, wat daarop dui dat dit slegs 'n lewensvatbare bron van voedingstowwe is indien dit by hoër en konsekwente tempos toegedien word of alternatiewelik wanneer formulering daarvan verbeter word. Sanjeevak was ook ontleed vir die mikrobiologiese eienskappe en die vlakke van swaar metale in vergelyking met die streng wetgewing wat die gebruik en toediening van afvalwater slyk op landbougrond in Suid-Afrika reguleer. Die bevindinge het getoon dat swaar metale en fekalieë kolivorm vlakke hier gemeet, aan die drumpel vereistes voldoen vir die toediening as ‘n grondverbeteringsmiddel. Studies wat die opsporing en die konsentrasie van fitohormone in Sanjeevak ondersoek is uitgevoer. In die gebruik van die Salkowski kolorimetrise metode om die ouksiene op te spoor en te kwantifiseer uit Sanjeevak en sy mengsel (beesurine en mis), het die resultate die teenwoordigheid van indol-3-asynsuur (IAA) by wisselende konsentrasies wat wissel van 20 tot 140 ppm in beesurine, beesmis en Sanjeevak getoon. Evaluering van die bogenoemde monsters vir IAA met behulp van LC-MSanalise bevestig vroeër bevindings. Verdere ontleding van hierdie resultate beklemtoon sterk die invloed van Sanjeevak mikrobiota in fitohormone produksie. Proewe is uitgevoer in die glashuis en die veld. In die glashuis eksperimente, is het die verskeie toedieningstempo van Sanjeevak herhalend die wortelbevorderende effekte bevestig op gewasse soos tamaties, komkommer en wingerdstok en dit het opbrengs van koring verhoog, onafhanklik van die voedingstowwe wat dit bevat. Statistiese analise van die resultate verkry onder veldtoestande, het getoon dat daar geen verskil tussen die behandelings (kontrole, kompos, Sanjeevak en kompos + Sanjeevak) was nie, gegee dat dieselfde gewas getoets was. Ten slotte, laboratorium-eksperimente op Sanjeevak as voor-behandeling om die beworteling te verbeter van die wingerdstok (Ramsey) onderstok steggies, het baie belowende resultate getoon in vergelyking met naftaleen asynsuur (NAA) voorbehandeling en die kontrole. Dit beklemtoon die feit dat Sanjeevak 'n alternatief kan wees en wat verdere studie verdien, hoofsaaklik as gevolg van sy lae-koste en omgewingsvriendelike prosedures. Die gebruik van Sanjeevak as 'n organiese grondverbeteringsmiddel vir gewasproduksie en voortplanting kan beskou word as' n goedkoper alternatief tot effektiewe mikro-organisme (EM) tegnologie wat uit plaaslike en natuurlike hulpbronne saamgestel is. Soos waargeneem in die studie, kan dit die beste gebruik word in kombinasie met 'n betroubare bron van plantvoedingstowwe. Dus, moet die gebruik daarvan vir die produksie van gewasse en voortplanting aangemoedig word.
364

Potential for methane digesters on U.S. dairy farms

Brooks, Dana L. January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Christine Wilson / Methane digesters are a potential investment for a dairy farm. A digester can lower greenhouse gas emissions, manage manure waste, generate energy, provide fertilizer and recycle bedding. The AgSTAR project of the Environment Protection Agency describes anaerobic digesters as a solution to a problem dairy farmers have always had to solve but that has become more acute with the innovation of larger scale, confined animal feeding operations developed in response to the growing food demands of the world’s larger and more prosperous middle class population – what to do with cow manure. Digesters take cow manure and convert it into energy while also eliminating manure odor. Energy is the primary economic benefit of a digester. A dairy farmer can use the electricity or gas generated from the digester to fuel the energy needs of the farm. Selling gas or electricity on the market is a revenue source that largely determines the level of profit from investing in a digester. This thesis will explore the four economic factors required to make anaerobic digesters a viable economic investment for a 1,500 head cow herd in the United States. It is imperative that farmers are able to obtain a return on the investment as soon as possible as many do not have the capital to invest in a nearly $1 million project. Congress may need to provide additional incentives for farmers and utility companies to take waste and process to energy. The future for methane digesters looks profitable when energy and carbon markets are available and allowed to trade competitively. The federal government may consider focusing on incentives for the utility companies’ infrastructure to make purchases of renewable energy from a digester more economically attractive and efficient. Today, an obstacle for increasing the number of digesters in the United States is the cost associated with moving the energy from the digester and into the national natural gas to grid. Natural gas companies may need to be compensated for that expense plus the potential difficulties of dealing with multiple suppliers or digester owners. Electricity companies have a grid in place to power rural and urban communities. They have spent billions of dollars and decades to establish efficient routing of power to residents and businesses. Manure digesters are mostly located in rural areas that would also require an investment in infrastructure to move the energy from the digester to the power grid. Mandating net-metering would require energy companies to purchase renewable energy, but consumers may see an increase in their cost. Therefore, the answer to increasing the number of manure digesters in the United States may be to direct the incentives to utility companies to invest in expanding infrastructure rather than increasing digester owner subsidies. Although, the REAP grants are helpful for assisting farmers with startup installation costs, there may not be a need to increase that subsidy in the next farm bill if an energy bill includes incentives for energy companies to purchase renewable energy from digesters.
365

Produção biotecnológica de metano a partir da codigestão de dejeto líquido suíno com resíduos de hortifruti /

January 2019 (has links)
Resumo: A suinocultura atingiu índices elevados de produtividade por meio do emprego de avançadas tecnologias de produção, resultando em maior geração de dejeto líquido suíno (DLS) com grande potencial de contaminação de águas mananciais. O resíduo de hortifruti (RH) é produzido em grandes quantidades nos mercados atacadistas, sendo caracterizado pelo elevado teor de umidade e de compostos orgânicos voláteis, o que causa efeitos negativos nos sistemas tradicionais de destinação dos resíduos sólidos urbanos. A codigestão de dejetos suínos e resíduos orgânicos vem sendo amplamente estudada, com melhorias na degradação dos substratos em digestão e, consequentemente, dos rendimentos de biogás. Assim, neste trabalho, avaliou-se o desempenho da codigestão de dejetos de suínos e crescentes níveis de resíduos de hortifrúti, utilizando-se um delineamento fatorial de experimentos 2³ (3 fatores, 2 níveis) seguido de modelagem matemática para descrever o volume de metano acumulado durante o bioprocesso. Para a realização dos ensaios, foram preparadas misturas de substratos compostas por dejeto líquido suíno e resíduo de hortifruti nas relações 4:1, 2,5:1 e 1:1, as quais foram inoculadas e digeridas em frascos batelada por tempos de retenção hidráulica de 20 a 30 dias e temperaturas de 35 a 45°C. Os maiores rendimentos foram de 455,47 e 442,37 NmL CH4/g SVT e ocorreram nos ensaios com relação DLS:RH de 2,5:1 e 1:1, respectivamente. A relação DLS:RH foi significante para o acúmulo de metano durant... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Swine production reached high levels of productivity through the use of technology, resulting in higher generation of swine manure (SM) with great potential for ground water contamination. Fruit and vegetable waste (FVW) are produced in large quantities in wholesale markets, characterized by high moisture content and volatile organic compounds, causing negative effects in the traditional systems of municipal solid waste disposal. The codigestion of swine manure and organic wastes has been widely explored, with improvements in the degradation of the substrates in digestion and, consequently, of the biogas yields. Thus, in this work, the performance of the codigestion of SM and increasing levels of FVW were evaluated using a factorial design of experiments 2³ (3 factors; 2 levels) followed by mathematical modelling to describe the volume of methane accumulated during the bioprocess. In order to carry out the assays, mixtures of substrates composed of SM and FVW were prepared in the ratios 4:1, 2,5:1 e 1:1, which were inoculated and digested in batches with hydraulic retention times of 20 to 30 days and temperatures of 35 to 45 °C. The maximum yields were 455.47 and 442.37 NmL CH4 / g VS and occurred in assays with 2.5:1 and 1:1 SM:FVW ratios, respectively. The SM:FVW ratio was significant for the accumulation of methane during the process, while the hydraulic retention time was not significant at a 95% confidence level. The temperature was marginally significant, with a higher ... (Complete abstract click electronic access below) / Mestre
366

Pratylenchus brachyurus x algodoeiro: patogenicidade, métodos de controle e caracterização molecular de populações / Pratylenchus brachyurus x cotton: pathogenicity, control methods and molecular characterization of populations

Machado, Andressa Cristina Zamboni 04 October 2006 (has links)
Pratylenchus brachyurus é um dos nematóides mais disseminados na cultura do algodão nas áreas produtoras do Brasil. Sua patogenicidade ao algodoeiro, entretanto, é pouco estudada. Os objetivos deste trabalho foram: i) correlacionar níveis populacionais iniciais crescentes de P. brachyurus (0, 12.000, 30.000 e 75.000 exemplares/ planta) com os danos causados ao algodoeiro \'Delta Opal\'; ii) avaliar a patogenicidade de populações de P. brachyurus em algodoeiros \'Delta Opal\' e \'Fibermax 966\'; iii) testar cultivares de algodão em relação à reprodução de três populações de P. brachyurus ; iv) caracterizar a relação parasito-hospedeiro (em termos de suscetibilidade/resistência) de alguns adubos verdes, coberturas vegetais e pastagens a Pratylenchus brachyurus; v) caracterizar molecularmente populações de P. brachyurus, através de PCR-RFLP e seqüenciamento da região ITS-1 do rDNA. Os resultados sugerem que P. brachyurus é patógeno pouco agressivo da cultura do algodão, já que não se verificaram danos significativos às plantas em densidades populacionais do nematóide inferiores a 12.000 exemplares/ planta. Em relação às cultivares, todas foram suscetíveis a P. brachyurus . Entre as espécies vegetais testadas, as que se mostraram resistentes a P. brachyurus foram Crotalaria spectabilis, C. breviflora, amaranto \'BRS Alegria\', nabo forrageiro \'Comum\' e as cultivares de aveia preta Campeira Mor, IPFA 99006, Comum, CPAO 0010 e Garoa. As análises de PCRRFLP revelaram variabilidade genética entre as diferentes populações de P. brachyurus estudadas, em função dos diferentes padrões de bandas encontrados para as populações estudadas. O seqüenciamento da região ITS-1 do rDNA confirmou a variabilidade observada pela digestão enzimática, além de evidenciar heterogeneidade das regiões 18S e ITS-1 do rDNA de P. brachyurus / Although Pratylenchus brachyurus is widespread in Brazilian cotton fields, information about its importance as a cotton pathogen is scarce. The objectives of this work were: i) correlate crescent initial population densities (0; 12,000; 30,000; and 75,000 nematodes/ plant) with damage on cotton \'Delta Opal\'; ii) measure the pathogenic effect of P. brachyurus on cotton \'Delta Opal\' and \'Fibermax 966\'; iii) characterize the reaction of cotton cultivars to three populations of P. brachyurus ; iv) characterize the host reaction (in terms of susceptibility/ resistance) of some green manures, cover crops and pastures to two populations of P. brachyurus; v) characterize different populations of P. brachyurus by PCR-RFLP and sequencing of ITS-1 rDNA region. Results suggest that P. brachyurus is an eventual pathogen of cotton, since high population levels were necessary to reduce plant growth (< 12,000 nematodes/ plant). All cotton cultivars tested were rated as susceptible to P. brachyurus In relation to crop species tested, Crotalaria spectabilis, C. breviflora, amaranth \'BRS Alegria\', oil radish \'Comum\', and the black oat cultivars Campeira Mor, IPFA 99006, Comum, CPAO 0010, and Garoa were resistant to P. brachyurus PCR-RFLP showed intraspecific variability for different population of P. brachyurus studied. Sequencing of the ITS-1 rDNA region confirmed the results of the enzymatic digestion and demonstrated heterogeneity of 18S and ITS-1 rDNA regions of P. brachyurus.
367

Avaliação ecotoxicológica do uso de dejetos de suínos em solos de Santa Catarina / Ecotoxicological evaluation of swine manure usage in soils from Santa Catarina State Brazil

Segat, Julia Corá 25 June 2012 (has links)
O Brasil ocupa a quarta posição entre os maiores produtores mundiais de carne suína. Destaque nacional deve ser dado ao estado de Santa Catarina, que detém 25% da produção do Brasil. Em Santa Catarina, a intensificação da produção em pequena área territorial gera um grande aporte anual de dejetos de suínos por unidade de área agrícola. Isso se deve ao fato de que a alternativa mais utilizada para descarte desses resíduos é a sua aplicação como fertilizante agrícola, prática que tem gerado um dos maiores problemas de poluição ambiental, especialmente na região Oeste Catarinense. Poucos trabalhos com intuito de avaliar a toxicidade desse material aos organismos edáficos e sua interação com diferentes classes texturais de solos podem ser encontrados. Para avaliação desta toxicidade, uma ferramenta utilizada internacionalmente, e cada vez mais frequentemente no Brasil, é a ecotoxicologia terrestre. Esta técnica é utilizada para avaliar efeitos de substâncias que, quando adicionadas aos solos, causam impactos em organismos, mensurando as respostas de alterações na taxa de letalidade, reprodução, desenvolvimento e comportamento de organismos edáficos padronizados. Desta maneira, este estudo objetivou avaliar por meio de testes ecotoxicológicos os efeitos de doses crescentes de dejeto de suínos (D0: 0 m3 ha-1; D1: 25 m3 ha-1; D2: 50 m3 ha-1; D3: 75 m3 ha-1 e 100 m3 ha-1), em diferentes tipos de solo (Argissolo Vermelho Eutrófico S2; Latossolo Vermelho Distrófico S3 e Neossolo Quartzarênico S4 e Solo Artificial Tropical S1) na sobrevivência, reprodução e comportamento de minhocas (Eisenia andrei) e colêmbolos (Folsomia candida), através de metodologias padronizadas internacionalmente. Os resultados das avaliações com Eisenia andrei mostraram que no solo com menor teor de argila a toxicidade do dejeto causou letalidade de 100% dos indivíduos nas duas maiores doses testadas. Para os testes de toxicidade crônica, avaliando o potencial reprodutivo, as doses testadas em Neossolo Quartzarênico tiveram efeitos negativos em Eisenia andrei, mas nos outros solos não ocorreu efeito perceptível. Os resultados obtidos para testes com Folsomia candida mostraram toxicidade em todas as doses testadas, causando letalidade significativa dos indivíduos na menor dose de dejeto aplicada e, baseado nessa resposta, doses menores foram usadas para avaliar efeito crônico e no comportamento (0 m3 ha-1, 10 m3 ha-1, 15 m3 ha-1, 20 m3 ha-1 e 25 m3 ha-1). Os efeitos das doses usadas para o teste de reprodução foram significativamente diferentes dos observados no controle causando redução no número de juvenis gerados em todos os solos testados. As doses D3 e D4 no S2, assim como todas as doses no S3 causaram significativa fuga de colêmbolos para o solo não contaminado. Os resultados obtidos revelam a importância da utilização de solos naturais de diferentes texturas e diferentes organismos na avaliação de toxicidade de dejetos de suínos e também mostram que nesse caso os resultados dos testes com solo artificial tropical não podem ser extrapolados para solos naturais. / Brazil occupies the fourth place worldwide among the largest swine producers. National highlight should be given to Santa Catarina State, which stands for 25% of this production. In this state, the intensification of the production in a small area leads to a yearly huge supply of swine manure per unit of agricultural area. This is due to the fact that the most used methods to dispose swine manure is its application as a fertilizer on soils, which has been causing one of the largest environmental pollution problems, especially in the Western region of Santa Catarina State. Very few studies are available aiming to evaluate swine manure toxicity on edaphic organisms and its interaction with different textural classes of soil. To evaluate this toxicity ecotoxicology has been used around the world, and increasingly in Brazil. This technique is used to assess the effects of substances that, when applied on soil, cause impacts on the organisms, measuring their responses with regard to mortality rates, reproduction, development and behavior of soil organisms. Thus, this study aimed to evaluate, by means of ecotoxicological tests the effects of increasing swine manure doses (D0: 0 m3 ha-1; D1: 25 m3 ha-1; D2: 50 m3 ha-1; D3: 75 m3 ha-1 e 100 m3 ha-1) in different types of soil (Ultisols - S2; Oxisol S3 and Entisols S4) and in an Tropical Artificial Soil S1, on the survival, reproduction and behavior of earthworms (Eisenia andrei) and springtails (Folsomia candida), using standard international methodologies. The results of Eisenia andrei evaluations showed that, in sandy soils, swine manure toxicity caused 100% mortality of the organisms at the two largest doses tested. For chronic toxicity tests, evaluating the reproductive potential, there were negative effects of tested doses on Eisenia andrei in Entisols, but for the other soils there was no perceptible effect. The results of Folsomia candida tests showed toxicity for all the tested doses, causing significant mortality of the organisms even at the smallest dose applied. Therefore, smaller doses were used to evaluate chronic and behavioral effects (0 m3 ha-1, 10 m3 ha-1, 15 m3 ha-1, 20 m3 ha-1 e 25 m3 ha-1). The effects of applied doses for the reproduction test were highly different from those observed in the control treatment, always causing reduction in the number of produced juveniles for all types of soil tested. The D3 and D4 doses for S2, as well as, all the doses for S3, showed significant avoidance of springtails towards the uncontaminated soil. These data show the importance of the usage of natural soils with different textural classes and also different organisms in the evaluation of swine manure toxicity. Also, they show that the results for artificial tropical soils cannot be extrapolated to natural soils.
368

Uso contínuo de coberturas vegetais em citros: influência no banco de sementes, na comunidade infestante e nas características químicas do solo / Continuous usage of cover crops in citrus: influence in seedbank, weeds, and soil\'s chemical characteristics

San Martín Matheis, Hector Alonso 14 August 2008 (has links)
Nos últimos anos os consumidores, em especial do mercado externo, estão interessados e preocupados cada vez mais com a segurança alimentar, principalmente no que se refere à forma de produção. Esse panorama tem motivado a busca por alternativas de baixo impacto ambiental. Uma delas é o uso de coberturas vegetais ou adubação verde. Nesse contexto a presente pesquisa teve como objetivo avaliar a influência do uso contínuo de coberturas vegetais em pomar de citros sobre os padrões de infestação e banco de sementes das plantas daninhas, assim como as características químicas do solo. O experimento foi realizado em pomar de laranja \'Pêra\' (Citrus sinenesis (L.) Osbeck) na área experimental da Escola Superior de Agricultura \"Luiz de Queiroz\", Universidade de São Paulo (USP), Piracicaba, SP. O delineamento utilizado foi de blocos ao acaso em esquema fatorial 4 x 2 x 2. Os tratamentos consistiram da combinação de quatro coberturas vegetais, dois tipos de roçadeira e dois tipos de adubação. As coberturas vegetais utilizadas foram labe-labe (Dolichos lablab L.), guandu-anão (Cajanus cajan L. Millsp cv IAPAR 43), milheto (Pennisetum glaucum (L.) Leeke) e infestação natural do pomar de laranja. As roçadeiras utilizadas foram do tipo lateral e convencional e a adubação foi realizada na entrelinha e na projeção da copa da planta cítrica. Pelos dados obtidos pode-se observar que: as coberturas mortas produzidas pela infestação natural e pelo labe-labe contribuem significativamente na redução das populações de plantas daninhas afetando o banco de sementes; nas linhas das laranjeiras as plantas daninhas dicotiledôneas ocorreram com maior freqüência e com maior importância relativa em relação às monocotiledôneas; o deslocamento contínuo de cobertura morta da infestação natural promoveu alterações no pH, matéria orgânica (MO) e magnésio (Mg); o deslocamento contínuo de cobertura morta do labe-labe incrementou os teores de fósforo (P), cálcio (Ca), magnésio (Mg) e saturação por bases (V%). Sendo assim pode se concluir que o labe-labe pode constituir-se em alternativa promissora para uso como cobertura intercalar na cultura de citros. / In the last few years, the consumers, especially those of the external market, have become more and more interested in food security, namely on what it refers to the means of production. This fact has motivated the search for alternatives of low environmental impact, and one of these is the use cover crops or green manure. In this context the current research aimed the evaluation of the influence of continuous usage of plant cover in citrus orchards over the patterns of infestation and weed seed bank, as well as the soil\'s chemical characteristics. The experiment was carried out in a \"Pêra\" orange orchard (Citrus sinensis (L.) Osbeck) at the experimental area of Escola Superior de Agricultura \"Luiz de Queiroz\", University of São Paulo (USP), Piracicaba, SP. The experiment was conducted in random blocks in a 4 x 2 x 2 factorial scheme. The treatment consisted on the combination of four cover crop, two kinds of mowers and two kinds of manure. The cover crops used were lab-lab Dolichos lablab L., Cajanus cajan L. Millsp cv IAPAR 43, Pennisetum glaucum L. Leeke and natural infestation of the orange orchard. Lateral and conventional mowers were used, and the fertilization was made on inter row as well as on the projection of the trees\' crowns. The following facts were observed from the data that were gathered: the plant cover produced by natural infestation and D.lablab contributed significantly for the reduction of the weeds\' population, and thus having an effect on the seed bank; at the citrus tree\'s rows the dicotyledonous plants had higher relative frequence and relative importance than monocotiledonous plants; the continuous displacement of mulch natural infestation increased pH, organic matter (OM) and magnesium (Mg); the continuous displacement of mulch D.lablab increased phosphorus (P), calcium (Ca) and magnesium (Mg) levels and base saturation (V%). Thus, we can conclude that D.lablab can be a promising alternative as cover crop in citrus cultivation.
369

Tratamento da fração líquida de estrume bovino em reator anaeróbio híbrido em escala piloto / Treatment of liquid fraction of dairy manure in a pilot-scale anaerobic hybrid reactor

Dias, Pâmela Castilho 06 October 2017 (has links)
O presente trabalho teve como principal objetivo avaliar o desempenho de um reator anaeróbio híbrido (RAnH) em escala piloto no tratamento da fração líquida de estrume bovino, visando à remoção de matéria orgânica e à produção de biogás. O RAnH estudado apresentava volume total 6,2 m3 e foi composto por manta de lodo, na qual a biomassa encontrava-se suspensa, e leito fixo, no qual utilizou-se Biobob&#174; como material suporte para imobilização da biomassa. Para dar suporte a partida do RAnH, a água residuária em estudo foi submetida a teste de biodegradabilidade visando avaliar a influencia da inoculação do reator no potencial de biodegradabilidade e de produção de metano. No teste, a inoculação mostrou-se adequada, apresentando biodegradabilidade de 57 &#177; 4% e produção de metano de 344 &#177; 26 mL CH4. g SV-1. A operação do RAnH foi realizada por 260 dias e foi dividida em duas etapas: etapa inicial, na qual se procedeu a adequação da operação do reator, e etapa experimental, na qual se avaliou o desempenho do reator perante o aumento progressivo da carga orgânica aplicada. Durante a operação do reator foi alcançada a aplicação de COV bruta total de 25,50 &#177; 2,53 kg DQO.m-3.d-1 e a COV solúvel total de 7,69 &#177; 0,02 kg DQO.m-3.d-1, sendo atingido o TDH de 1,27 &#177; 0,004 d. O RAnH apresentou eficiência de remoção média de 65 &#177; 4 % durante a etapa experimental. A produção média de metano foi de 0,310 &#177; 0,095 m3 CH4. m-3.d-1 e 0,098 &#177; 0,018 m3 CH4. kg SVad, com 89 &#177; 3% de metano na composição do biogás. O potencial de produção de energia elétrica estimada com base no reaproveitamento metano produzido no RAnH foi de 0,89 kWh.m-3. O aproveitamento desta energia em sistema com vazão de 3.500 m3.d-1 geraria energia suficiente para abastecer 615 residências e uma economia mensal de R$ 11.835,09. / The main objective of this work was to evaluate the performance of a pilot-scale anaerobic hybrid reactor (RAnH) in the treatment of the liquid fraction of dairy manure, in order to remove organic matter and produce biogas. The applied RAnH had a total volume of 6.2 m3 and was composed of sludge blanket, in which the biomass was suspended, and fixed bed, in which Biobob&#174; was applied as a support material for biomass immobilization. In order to support RAnH startup, the wastewater under study was submitted to a biodegradability test to evaluate the influence of reactor inoculation on the biodegradability potential and methane production potential. In the test the inoculated condition presented appropriate biodegradability (57 &#177; 4%) and higher methane production potential (344 &#177; 26 mL CH4.gVS-1). The RAnH operation was performed for 260 days and was divided into two stages: initial stage, in which the reactor operation was adjusted, and the experimental stage, in which the reactor performance was evaluated with the progressive increase of the applied organic load. During the reactor operation was reachead total raw VOC application of 25.50 &#177; 2.53 kg COD m-3.d-1 and total soluble VOC of 7.69 &#177; 0.02 kg COD m-3.d-1, with the HRT of 1.27 &#177; 0.004 d. The RAnH presented average removal efficiency of 65 ± 4% during the experimental stage. The average methane production was 0.310 &#177; 0.095 m3 CH4.m-3.d-1 and 0.098 &#177; 0.018 m3 CH4. kg VSad, with 89 &#177; 3% of methane in the biogas composition. The potential of electric energy production estimated based on the reuse of the methane produced in the RAnH was 0,89 kWh.m-3. The use of this energy in a system with a flow of 3,500 m3.d-1 would generate sufficient energy to supply 615 homes and a monthly saving of R$ 11,835.09.
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Digestão anaeróbia de dejeitos suínos: um estudo para verificar a influência da adição de meios de cultura. / Anaerobic digestion of swine litter: a study to verify the influence of the addition of culture media.

GOMES, Damião Junior. 28 May 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-28T14:27:42Z No. of bitstreams: 1 DAMIÃO JUNIOR GOMES - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1021631 bytes, checksum: 9d3b509edbbf52efa1db00de496731a6 (MD5) / Made available in DSpace on 2018-05-28T14:27:42Z (GMT). No. of bitstreams: 1 DAMIÃO JUNIOR GOMES - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1021631 bytes, checksum: 9d3b509edbbf52efa1db00de496731a6 (MD5) Previous issue date: 2014-12-19 / Este estudo analisa o comportamento físico químico e microbiológico, referente à mistura de resíduos suínos com e sem adição de meios de cultura descartados, durante o processo de biodigestão anaeróbia, em biorreator tipo batelada. Montaram-se dois biorreatores, para fim de comparação, com capacidade de 50L cada. Os biorreatores foram ativados com a mesma diluição, razão de 1:2 (mistura biomassa/água, em m/m), no entanto, em um deles foi acrescidos 10% (m/m) de meios de culturas usados oriundos de um laboratório microbiológico. O monitoramento destes procedera por 56 dias, sendo coletadas alíquotas dos substratos nos tempos 0, 7, 21, 28, 35, 42, 49 e 56 dias, e submetidos à caracterização físico-química e microbiológica, bem como, verificou-se a influência dos meios de cultura na produção de biogás. Durante o desenvolvimento não se realizou nenhuma suplementação nos biodigestores. Os dados experimentais apontaram que durante o processo da biodegradação anaeróbia dos substratos, o biorreator A (com presença de meios de cultura) desempenhou melhores resultados, em relação ao biorreator B (com ausência de meios de cultura). Como por exemplo, pH’s próximos da alcalinidade, propiciando o desenvolvimento das bactérias metanogênicas, e consequentemente, maior liberação de gases. No que concerne aos valores de concentração de coliformes totais (35 ºC), termotolerantes (45 ºC) e E. coli entre os afluentes e efluentes dos biorreatores, estes foram reduzidos, principalmente no biodigestor A, em que apresentou maior concentração de macronutrientes (NPK). Por fim, pode ser inferido que os resultados foram bastante relevantes, fazendo entender que a introdução de meios de cultura potencializa as reações de biodigestão anaeróbia, favorecendo maior produção de biogás, além de incorporar ao efluente (biofertilizante) maior concentração de nutrientes. / This study analyzes the chemical and physical behavior microbiological, regarding the mixture of swine residues with and without addition of discarded culture means, during the process of anaerobic digestion, in bioreactor boat-load type. Two bioreactors were set up, for comparison end, with capacity of 50L each. The bioreactors were activated with the same dilution, reason of 1 : 2 (it mixes biomass / water, in m/m), however , in one of them was added 10 % (m/m) of means of cultures used originating from of the microbiological laboratory . The monitoring of these it had proceeded for 56 days , being collected brackets of the substrata in the times 0, 7, 21, 28 , 35, 42, 49 and 56 days, and submitted to the physiochemical characterization and microbiological, as well as, the influence of the culture means was verified in the biogas production. During the development it did not take place any supplementation in the digesters. The trial date appeared that during the process of the anaerobic biodegradation of the substrates, the bioreactor (with presence of culture means) it carried October better results, in relation to the bioreactor B (with absence of culture means). For example, close pH 's of the alkalinity , propitiating the development of the methanogenic bacteria , and consequently , larger liberation of gases. In what it concerns to the values of concentration of the total coliforms (35 ° C), thermophilic (45 ° C) and E. coli between the tributaries and effluents of the bioreactors, these were reduced, mainly in the digester, in that It presented larger macronutrient concentration (NPK ). Finally, it can be inferred which the results were quite relevant, making that to understand the introduction of culture means potentiates the reactions of anaerobic digestion , favoring larger biogas production, fouled Incorporating to the effluent (biofertilizer) larger concentration of nutritious.

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