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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.
91

Energy Extraction from Horse Manure Biogas plant vs. Heating Plant : A Case Study in Wången

Moazedian, Amitis January 2013 (has links)
Wången is a trotting school located in Alsen region in Mid Sweden. Currently they keep almost 105 horses in their premises, which produce 2 400 m3 of stall waste per year.  Stall waste has always been a concern for those who keep animals, and though composting has been a viable solution to this problem for quite some time, it is no longer the only solution. Stall waste can be converted to energy and there are different techniques and approaches to do so.  In this study the writer compares the viability of two possible techniques (Biogas and heating plant) by collecting data from two existing biogas and heating plant providers for Wången trotting school. The results show that with almost same amount of investment on the reactors, a heating plant can meet 85% of Wången heating demand while Biogas plant could only meet 10 % of Wången’s heating consumption. On the other hand, as a result of nitrogen bound compound existence in horse manure, burning stall waste in the heating plant showed a more acidifying potential compared to the biogas plant. / Investigation for Wången trotting school
92

Cool season mineralization of recalcitrant organic nitrogen in manured soils /

Moberg, Dean Paul. January 2008 (has links)
Thesis (Ph.D.) OGI School of Science & Engineering at OHSU, March 2008. / Includes bibliographical references.
93

Phosphorus dynamics in Tennessee soils receiving various forms of long-term manure application /

Franks, Laura Ruth, January 2000 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2000. / Vita. Includes bibliographical references. Also available via the Internet.
94

The availability of potassium to plants as affected by stable manure

Bartholomew, R. P. January 1926 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1926. / Typescript. With this is bound: The availability of potassium to plants as affected by stable manure / R.P. Bartholomew, reprinted from the Journal of the American Society of Agronomy, vol. 20, no. 1 (Jan. 1928), p. 55-81. Includes bibliographical references (leaves 89-91).
95

Differential optical absorption spectroscopy (DOAS) measurements of atmospheric ammonia in the mid-ultraviolet from a dairy concentrations, emissions, and modeling /

Rumburg, Brian Paul, January 2006 (has links) (PDF)
Thesis (Ph.D.)--Washington State University, May 2006. / Includes bibliographical references (p. 162-170).
96

Eficiência da utilização de adubos verdes em pomar de laranjeira 'Pêra' (Citrus sinensis (L.) Osbeck)

Ragozo, Carlos Renato Alves [UNESP] 20 December 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-20Bitstream added on 2014-06-13T19:03:05Z : No. of bitstreams: 1 ragozo_cra_dr_botfca.pdf: 331427 bytes, checksum: a7e833594247681e7c4ad5ac7e49b4c4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho teve como objetivo avaliar a eficiência da utilização de adubos verdes em pomar de laranjeira 'Pêra' (Citrus sinensis (L.) Osbeck) e foi instalado na fazenda Três Irmãos, no município de Botucatu/SP. O solo da propriedade é denominado Neossolo Quartzarênico. As plantas estão enxertadas em limoeiro 'Cravo' e foram plantadas num espaçamento de sete por quatro metros, no ano de 1996, estando com sete e oito anos de idade respectivamente nos anos de 2003 e 2004, ocasião em que foi realizado o experimento. Foram empregados quatro tratamentos correspondentes aos adubos verdes avaliados, sendo eles: feijão de porco (FP) (Canavalia ensiformis DC), labe-labe (LL) (Dolichus lablab L.), feijão guandu anão (GA) (Cajanus cajan L. Millsp) e braquiária (BQ) (Brachiaria brizantha Hochst ex A. Rich. Stapf). Os adubos verdes foram semeados no mês de dezembro dos anos de 2003 e 2004, sendo ceifados e direcionados para a linha da cultura na ocasião do pleno florescimento, o que corresponde a cento e vinte dias após a semeadura dos mesmos. Adotou-se os mesmos tratos culturais indicados para a cultura, nos dois anos de experimentação. O delineamento experimental foi em blocos ao acaso com quatro tratamentos, seis repetições, duas plantas úteis para as avaliações, completamente rodeadas por plantas bordadura. As características avaliadas foram: análise química de solo nas linhas e entrelinhas da cultura, diagnose foliar, diagnóstico nutricional através do DRIS (Sistema Integrado de Diagnose e Recomendação), circunferência do tronco (cm), volume de copa (m3), índice relativo de clorofila (índice Spad), peso médio dos frutos (g) número de frutos por caixa, rendimento de suco (%), acidez total (g de ácido cítrico / 100g de polpa), sólidos solúveis totais (SS), ratio, produtividade, porcentagem de matéria seca dos adubos verdes... / The purpose of the experimental was to evaluate the efficiency of the use of the green manures on an orchard planted with orange (Citrus sinensis Osbeck) cv. 'Pera' and was carried out in a farm named 'Três Irmãos', situated in Botucatu/SP/Brazil. The soil is Oxic Quartzipsamments. Plants are grafted on 'Cravo' lemon tree and were planted spaced 7 x 4 m apart, in 1996, and were seven and eight years old in 2003 and 2004, respectively when the experiment was conducted. Four different treatments were applied corresponding to the three green manures: jack bean (FP) (Canavalia ensiformis DC), lab-lab (LL) (Dolichus lablab L.), dwarf guandu (GA) (Cajanus cajan L. Millsp) and brachiaria (BQ) (Brachiaria brizantha Hochst ex A. Rich. Stapf) as a control. They were sown on December, 2003 and 2004, being mowed and directed to the line plants by the occasion of the full flowering, wich happened one hundred and twenty days after sowing. The same treatments were utilized in both experimental years. The experimental design was a randomized blocks with four treatments, six replications, and two useful plants per plot. Characteristics evaluated were: chemical analysis of the soil over the planting lines and in the middle of the citrus orchard rows, chemical analysis of the leaves, nutritional diagnosis through the DRIS, trunk circumference (cm), volume of the canopy (m3), relative index of chlorophyll (SPAD index), average fruits weight (g), number of fruits per boxes, juice content (%), total acidity (g of citric acid / 100 g of pulp), total soluble solids, ratio, productivity, percentage of dry matter and the contents of macro and micronutrients in the green manures and control (BQ). The results obtained allowed the following conclusions: the nutritional diagnosis elaborated through DRIS showed...(Complete abstract click electronic access below)
97

Isolamento, seleção e estudo de microrganismos ligninoliticos degradadores de chorume / Isolation, selection and study of microorganisms ligninolytic decomposers of manure

Bavutti, Hamilton Roberto Fortes 01 August 2018 (has links)
Orientador : Lucia Regina Durrant / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-01T23:55:15Z (GMT). No. of bitstreams: 1 Bavutti_HamiltonRobertoFortes_D.pdf: 34939085 bytes, checksum: 2fbad9e1098a28b05a4e68c56a2847ef (MD5) Previous issue date: 2002 / Resumo: O objetivo deste trabalho foi estabelecer parâmetros para a degradação biológica de várias amostras de chorume obtidas de um aterro sanitário da região metropolitana de Campinas, determinar os tipos de microrganismos mais comumente encontrados nestas amostras e estudar o metabolismo dos mesmos. Inicialmente 323 linhagens foram isoladas utilizando-se o meio de cultura R2A. Estas linhagens foram testadas quanto a sua resistência frente a compostos tóxicos e crescimento sobre lignina. Foram realizados 8 experimentos mudando-se as características de cultivo e alguns parâmetros foram observados, tais como degradação de fenol, degradação de compostos tóxicos presentes no chorume, redução da demanda química de oxigênio (OQO) e diminuição da cor. 00 total delinhagens analisadas, 4 linhagens fúngicas mostraram-se mais adequadas para conseguir degradar os compostos altamente poluentes presentes no chorume. As linhagens 74, 100, 108 e 184 foram testadas e a linhagem 184 destacou-se como sendo a melhor em quase todos os testes. Uma linhagem bacteriana (254) também atingiu bons resultados em alguns testes e merece outros estudos. O máximo de redução da OQO foi conseguido pela linhagem 184 nos experimentos IV (51,8%) e V (50,4%). As melhores taxas de degradação do fenol também foram atingidos pela linhagem 184 nos mesmos experimentos (72,9% e 63,7% respectivamente). A linhagem 100 também apresentou bons resultados e reduziu a OQO em 36,8% no experimento 111e 38,6% no experimento IV. Quanto à degradação do fenol, a mesma linhagem conseguiu taxas de degradação de 50,1 % no experimento IV. O chorume não autoclavado serviu melhor aos experimentos, bem como a adição de glicose e extrato de leveduras como nutrientes de crescimento / Abstract: The purpose of this work was to stablish parameters for the biological degradation of several leachate samples from a Campinas region's municipal sanitary landfill, to determine the kínd of microorganisms commonly found on these samples and to study their metabolism. Initally 323 strains were isolated using R2A medium. These strains were tested to toxical compounds resistance and ability to growth on lignin. Degradation of total leachate compounds, phenol degradation, DOO reduction and colour reduction were analysed in eíght different culture conditions. Four (4) fungal strains were more prepared to degrade the highly toxical leachate compounds. Strains 74, 100, 108 and 184 were tested and the strain 184 appeared to be the best in almost ali the conditions. One bacterial strain (254) also showed good results in some tests and deserves a detailed study. The maximum of DOO reduction was reached by the 184 strain in the experiments IV (51,8%) and V (50,4%). The best rates of phenol degradation were also reached by the strain 184 in the same experiments (72,9% and 63,7% respectiveUy). Strain 100 also presented good results and reduced the DOO around 36,8% in experiment 111and 38,6% in experiment IV. The same strain degradaded about 50,1% of phenol in the experiment IV. Non sterilized leachate added with glucose and yeast extract was better metabolized compared to non-added and sterilized leachate / Doutorado / Doutor em Ciência de Alimentos
98

Uptake, leaching, and storage of micronutrient metals in response to heavy applications of poultry manure

Safo, Ebenezer Yeboah January 1978 (has links)
The partitioning among plant uptake, leaching from and storage in soil of micronutrient metals following heavy applications of poultry manure was studied in three greenhouse experiments. Following these experiments, the study examined the effect of manure application on content and composition of soil organic matter and also the distribution of metals in the organic fractions. Poultry manure was surface-applied to Grigg and Monroe silt loam soil columns at rates of 0, 20 and 40 t/ha in each of the first two experiments, whereas the third tested the residual effect of the manure applications. Treatments were replicated four times and completely randomized. The soil columns were planted to corn (Zea mays L.) and leached daily with demineralized water at an average rate of 1.0 cm/day for 30-40 days. Following leaching and harvest of the corn, the soil columns were sampled in two sections for chemical analysis. Metals in the soils, leachates and corn tissue were determined by atomic absorption spectrophotometry. Manure application significantly (P < 0.01) influenced corn yield in Experiments I and II. The 20 t/ha rate increased yield more than the 40 t/ha treatment. Yield increases over the check treatment in Experiment I were about 400% and 300% from the 20 and 40 t/ha treatments respectively. In Experiment II, yield response was significantly curvilinear (P < 0.01), with the 20t rate giving the highest yield. The possibility of NH₃ toxicity and excess soluble salt injury resulting from the 40 t/ha rate was suggested. In Experiment III yield increases over the check treatment were about 300% and 500% from the 20 and 40 t/ha previous rates respectively. The study found no evidence for significant uptake or leaching of the toxic heavy metals (Cd, Cr, or Pb), such as is usually encountered with sewage sludge application. In Experiments I and II, total uptake of Mn, Fe, Zn, and Cu increased with the application of 20 t/ha and then decreased with the 40 t rate. In Experiment III, previous manure applications led to increases in uptake of these metals. The concentration of these metals in corn tissue decreased with the application of 20 t/ha and then increased with the 40 t rate in Experiment I. However, In both Experiments II and III the tissue metal concentration decreased with manure application. These effects were attributed largely to changes in yield. However, in no case did changes in concentration of metals exceed suggested tolerance limits. These results suggested that relatively high rates of poultry manure may be applied to the soil without appreciable danger of developing conditions of micronutrient metal toxicities. High manure rates led to increased leaching losses of K and Na. However, leaching losses of Mn, Fe, Zn, and Cu decreased with the application of 20 t/ha and then increased with the 40 t rate. Assuming independent contributions of metals from various potential sources, ratios of uptake and leaching losses to the input sources were examined. Both uptake and leaching losses of metals were small in magnitude in comparison with initial soil total levels and manure input. Despite the varied patterns of uptake and leaching losses of metals in response to the manure application, their storage in soil increased with rates of application. There was no consistent pattern in the distribution of metals in the top and lower halves of the soil columns after Experiments I and II. Examination of the distribution of organic fractions and associated metals following the greenhouse experiments indicated that soil organic matter content increased with manure application. The humic acid fraction made up 69 to 75% and the fulvic fraction 25 to 31% of the soil extractable organic matter. Despite such a high proportion of organic matter in the humic fraction, the data indicate that a greater proportion of metals in the organic fraction was associated with the fulvic fraction. / Land and Food Systems, Faculty of / Graduate
99

Optimering av biogasproduktion från gödsel / Optimization of Biogas Production from Manure

Özdemir, Gonca January 2009 (has links)
In this study, the bioconversion of manure and silage to biogas by an anaerobic digestion process in batch reactors was studied. Biogas is a valuable alternative energy source, mainly in rural areas. The main aim for the environment is to use biogas as a fuel instead of crude oil or natural gas. In this study, two different parameters were studied to observe the changes in methane productivity. The first three reactors were shaken once per week and the following three reactors were shaken 5 times per week. The results showed that mixing has no major effect on the methane production yield. In the second six reactors a mixture of 1% and 3% silage was added and the results were recorded. When the data from the reactors with just manure was compared to the reactors with 1% and 3% silage, it was seen that the silage increased the production rate and total gas produced. The process stabilization took a long time for digestion with the 3% silage possibly caused by release of too much fatty acids.
100

Effect of variable rates of cattle and poultry manure-based phospho-composts on growth, yield and quality of potato (Solanum tuberosum L.)

Mmadi, Mashupyane Josephine January 2019 (has links)
Thesis (M.Sc. (Soil Science)) -- University of Limpopo, 2019 / Phosphorus (P) deficiency has been reported in 30- 40% of global arable land, which poses a huge threat in potato production because of its critical role in the early vegetative development and tuber formation. The use of low cost ground phosphate rock (GPR) as an alternative P fertilizer source has gained recognition. Although GPR contains high P percentage, its direct application is less beneficial immediately due to its low reactivity which makes P unavailable for plant uptake. In this experiment, GPR was co-composted with cattle and poultry manure in order to enhance P acquisition by the potato crop. The aim of this study was to evaluate the potential of phosphocompost application as a cheaper alternative P-source for potato production. The experiment was conducted on Mondial and Valor… potato cultivars at the University of Limpopo Syferkuil Experimental farm in 2015 and 2016. Poultry (PM) and cattle manure (CM)-based phospho-compost mix ratios of 8:2 and 7:3 were applied at 0, 20, 40, 80 and 120 kg P/ha. The trial was laid out in a split plot arrangement fitted into a randomised complete block design with treatments replicated three times. Results indicated statistically significant effects of phospho-compost types on soil pH and available P content at both flowering and harvesting growth stages in 2015 and 2016 with the higher available P content found in the PM-based phospho-composts. In both seasons, highly significant differences in fresh and dry leaf samples among phospho-compost types were obtained. Highly significant season x compost type interaction effects were also recorded on leaf biomass as well as the 2015 tuber weight, with highest tuber weight obtained in plots that received PM7:3-based phospho-compost at 80 t/ha rate. Notwithstanding the non-significant effect of compost type on tuber yield in 2016, higher yield was obtained from PM8:2. Although the grading of tubers showed no significant response to phospho-compost application; the difference between small and medium tubers obtained from 2016 trial was significantly affected by phosphocompost application rates. The CM8:2 mix ratio gave the highest baby tubers (16.87%) while PM7:3 mix ratio gave the highest (36.32%) medium tubers. The grading of the potato tubers revealed a mostly class 1 dominated by baby, small and medium size tubers in the 2015 harvest while the 2016 harvest was also mostly class 1 but dominated by small, medium and large-small size tubers. Tuber size and class were vi most favored by the PM-based phospho-compost applications in both planting seasons. None of phospho-compost types and application rates had significant effect on the measured nutrient concentrations of both plant parts. However, the differences in nutrient concentrations across seasons and plant parts were significant except for Ca. The measure tissue P concentration from the 2016 trial was within the required range suggesting that phospho-compost utilization, particularly the poultry manure-based, in potato production can be beneficial in addressing P deficiency. The PM8:2 mixed ratio resulted in increased soil available P content, potato tuber yield in 2016 and the P concentration across the two plant parts evaluated. The concentration of soil available P and tissue P showed increases with higher application rates albeit non-significance. Future research on the optimum application rate is suggested on a wide range of soils for the various phospho-compost types. / Potato SA and the National Research Foundation (NRF)

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