• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 2
  • 1
  • 1
  • Tagged with
  • 10
  • 10
  • 4
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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.
1

The application of thermophilic anaerobic digestion in the degradation of poultry waste

Wetzel, Sharon January 2001 (has links)
No description available.
2

Anaerobic Digestion of Low Rate Digesters in Temperate Climates

Castano, Juan Mauricio 30 August 2012 (has links)
No description available.
3

Effect of Organic Amendments on Heavy Metal Distribution and Uptake in Vegetable Gardens in Senegal

Diouf, Aissatou 23 September 2016 (has links)
The major constraints to food production in West Africa are related to the lack of suitable lands. Consequently, farmers incorporate organic amendments and wastewater to improve their yields. Within some limits, such wastes enhance soil fertility and can improve its physical properties. However, the advantages of using organic waste as fertilizer and soil amendment should be assessed with possible environmental and toxicological impacts due to the potential presence of heavy metals. The objective of this study was to assess the effect of organic amendments on heavy metal distribution in soils and vegetables in market gardens in Senegal. Organic amendments and soils samples were collected from four sites in eastern and southern Senegal. Samples were analyzed for physicochemical properties including particle size, total heavy metals, carbon content, nutrients, and pH. A sequential extraction procedure was conducted to determine heavy metal sinks. Results showed that sites were sandy in nature, low to medium in organic carbon content (8300 to 36600 mg kg-1), and had pH ranging from 5 to 7.9. The sequential extraction procedure showed that metals were distributed in the more stable soil fractions: Fe-Mn oxide, organic and residual. The highest soil metal concentrations in soils were found in Pikine and Rufisque sites. Plant samples were collected from these two sites and analyzed for total metal content. Results showed that all metal concentrations in soils, organic amendments, and vegetables were within the safe limits proposed by the World Health Organization, with the exception of Cd, Pb and Zn levels in vegetables. / Master of Science / Application of composted organic wastes and untreated wastewater to urban vegetable garden soils is raising serious concerns about possible health risks associated with the consumption of these vegetables particularly with regard to the concentrations of heavy metals in their edible portions. Therefore, this study focused on the evaluation of heavy metal concentrations in soils, organic amendments and vegetables from local gardens of Senegal and also, the determination of metal sinks in soil phases via a sequential extraction procedure (SEP). Soils, organic matter and vegetable concentrations of cadmium, cobalt, chromium, copper, manganese, nickel, lead and zinc were analyzed for total metals. Results from the SEP showed that metals in soils were located on the stable soil phases and would not be easily released unless environmental conditions changed (e.g. more acidic pH or anoxic conditions). Data from total metal analyses revealed that all metal concentrations in soil, organic amendments, and vegetables were within the safe limits proposed by the World Health Organization (WHO) with the exception of Cd, Pb and Zn levels in vegetables.
4

Characterization of the larval habitat of Culicoides sonorensis (Diptera: Ceratopogonidae) with emphasis on the significance of animal manure and the associated bacterial community

Erram, Dinesh January 1900 (has links)
Doctor of Philosophy / Department of Entomology / Ludek Zurek / The larval stages of Culicoides sonorensis Wirth and Jones, a confirmed vector of bluetongue and epizootic hemorrhagic disease viruses affecting ruminants in North America, have been observed to occur typically in animal waste enhanced muds. In this dissertation, I studied the larval development (first instar to adult stage) and oviposition (four-choice assays) of C. sonorensis on sterilized mud (autoclaved) enriched with manure of different farm animal species (dairy cattle, beef cattle, sheep, goats, pigs, horses, white-tailed deer, and chicken). In addition, to determine why only some manure-polluted sites are colonized by C. sonorensis even when they are in close proximity to each other, I examined the moisture levels and microbial concentrations (mud) and physicochemical characteristics (standing water) of a manure-overflow pond site producing C. sonorensis and compared them to nearby cattle stock pond site(s) that produced different Culicoides species. Finally, as the first step in examining the role of microbiome in various physiological functions of C. sonorensis and other suspected/potential vector Culicoides species, I assessed the bacterial communities in field-collected adult females of C. sonorensis, C. crepuscularis, C. haematopotus, and C. stellifer (Illumina sequencing of 16S rRNA gene). In larval development experiments, the proportion of adults emerged and development time to adult stage varied with manure type and its concentration present in the substrate. Mud supplemented with chicken manure did not support C. sonorensis development, mud enriched with white-tailed deer manure poorly supported midge development, while C. sonorensis development in mud enhanced with manure of sheep, goats, beef cattle, dairy cattle, pigs, and horses varied. In oviposition experiments, colonized females preferred to deposit eggs on substrates without animal manure over substrates with animal manure. In subsequent studies, the manure-overflow pond site that produced mainly C. sonorensis contained significantly higher total aerobic culturable bacteria, pH, salinity, total dissolved solids, and conductivity levels than cattle stock pond sites that produced different Culicoides species. Finally, bacterial composition of field-collected C. sonorensis adult females comprised mainly of the phyla Proteobacteria and Firmicutes, while the majority of bacterial taxa identified from C. crepuscularis, C. haematopotus, and C. stellifer belonged to Proteobacteria. An unidentified bacterial genus (related to Tumebacillus), Propionibacterium, and Curvibacter were detected commonly across all four midge species. These results suggest that manure of several farm animal species can contribute to C. sonorensis development in the field. However, oviposition preferences remain uncertain, as colonized females appeared to show aversion to animal manure, which is in contradiction to the typical presence of C. sonorensis larvae in animal waste enhanced muds. Nonetheless, variations in microbial and/or physicochemical conditions in the larval habitats likely play a role in the differential emergence of C. sonorensis from various manure-polluted sites. Moreover, some bacterial taxa are associated commonly with C. sonorensis and other suspected/potential vector Culicoides species. Future studies are needed to examine oviposition preferences of field-collected females, life history traits of adults emerging from various manure-enriched substrates, developmental requirements of larvae, and the role of microbiome in various physiological functions of the host including vector competence for orbiviruses.
5

Volatilização de amônia com o uso de dejetos de suínos com pH modificado / Ammonia volatilization using swine manure with modified pH

Muller, Fernando 27 March 2018 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-09-26T13:43:20Z No. of bitstreams: 2 Fernando_Muller_2018.pdf: 512041 bytes, checksum: 2ff86626a282d8b0ea9a5d679b8fd5a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-26T13:43:20Z (GMT). No. of bitstreams: 2 Fernando_Muller_2018.pdf: 512041 bytes, checksum: 2ff86626a282d8b0ea9a5d679b8fd5a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-27 / In western Paraná the production of pigs in feedlot system is in a large scale, resulting in a wide production of manure with a high power of environmental pollution if not treated correctly. The use of this manure as biofertilizers may be an interesting alternative for the agricultural sector by providing nutrients to plants, especially nitrogen. In addition, the biofertilizer can improve soil fertility by increasing its organic matter. However, after the application of nitrogen to the soil, gaseous losses of this nutrient may occur, denominated ammonia volatilization, which can be intensified by different factors. Thus, the objective of this work was to evaluate the fertilization of soybean with liquid swine manure and the loss of nitrogen by volatilization after the application of it with different pHs. The work was conducted in two experiments. The first one was conducted in the 2015/2016 under no-tillage system with soybean crop. On the day of sowing, the treatments were composed of three doses of liquid swine manure (48; 96 and 144 m3 ha-1), plus additional treatments, which were the control (without fertilization) and a treatment with mineral fertilization (300 kg ha-1 of NPK formulation 04-30-10). The productivity of grains, green stems, heights of plants and one hundred grain mass were analyzed. The second work was conducted in a greenhouse during the period from October to December 2017. The ammonia volatilization was evaluated according to the adjusted pH of the liquid swine manure, being 3.0; 4.0; 5.0; 6.0 and 7.4 (natural manure). Further, two additional treatments were evaluated: natural manure + agricultural gypsum and the control (without application of manure). In order to capture the volatilized ammonia, Sale type collectors were used, with a static free semi-open chamber. The volatilization flow, accumulated volatilization and percentage of ammonia loss were analyzed. The mineral fertilization of soybean crop can be replaced by fertilization with liquid swine manure, mainly in high fertility soils. The fertilization with 48 m³ ha-1 was able to supply the nutritional need of the soybean crop according to the productivity obtained. The application of liquid swine manure with natural pH (7,4) provided high losses of ammonia, around 46 % higher. With the acidification of the manure by adjusting the pH around 3 to 5, a great reduction to 5 % of loss of nitrogen by volatilization was observed. / No oeste do Paraná a produção de suínos em sistema de confinamento é de grande escala, resultando em alta produção de dejetos, com grande potencial para poluição ambiental se não tratados de forma correta. A utilização desses dejetos como biofertlizante pode ser uma alternativa interessante para o setor agrícola pelo fornecimento de nutrientes às plantas, principalmente o nitrogênio. Além do mais, a aplicação do biofertilizante pode melhorar a fertilidade do solo pelo incremento da matéria orgânica. Entretanto, após a aplicação de nitrogênio no solo podem ocorrer perdas gasosas desse nutriente, principalmente sob a forma de amônia. Esse processo é denominado volatilização e pode ser intensificado por diferentes fatores. Assim, o trabalho teve por objetivo avaliar a adubação da soja com dejetos líquidos de suínos e a perda de nitrogênio por volatilização após a aplicação dos dejetos com diferentes pHs. O trabalho foi conduzido em dois experimentos. O primeiro foi conduzido na safra 2015/2016 em sistema de plantio direto com a cultura da soja. No dia da semeadura foram aplicados os tratamentos compostos por três doses de dejeto líquido de suínos (48; 96 e 144 m3 ha-1), mais os tratamentos adicionais, que foram a testemunha (sem adubação) e um tratamento com adubação mineral (300 kg ha-1 do formulado NPK 04-20-10). Foram analisados a produtividade de grãos, hastes verdes, alturas de plantas e massa de cem grãos. O segundo trabalho foi conduzido em casa de vegetação durante o período de outubro a dezembro de 2017. Foi avaliada a volatilização da amônia em função dos pHs ajustados do dejeto líquido de suínos, sendo 3,0; 4,0; 5,0; 6,0 e 7,4 (natural do dejeto). Além disso, foram avaliados dois tratamento adicionais: dejeto natural + gesso agrícola e a testemunha (sem aplicação de dejeto). Para captação da amônia volatilizada foram utilizados coletores do tipo Sale, com câmara semiaberta livre estática. Foram analisados o fluxo de volatilização; volatilização acumulada e porcentagem de perda de amônia. A adubação mineral da cultura da soja pode ser substituída pela adubação com dejeto líquido de suínos, principalmente em solos de fertilidade alta. A adubação com 48 m³ ha-1 de dejeto líquido de suínos foi capaz de suprir a necessidade nutricional da cultura da soja conforme a produtividade obtida. A aplicação do dejeto líquido de suínos com pH natural (7,4) proporcionou altas perdas de amônia, em torno de 46 %. Com a acidificação dos dejetos ajustando-se o pH em torno de 3 a 5 houve e redução para 5 % de perda de nitrogênio por volatilização.
6

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.
7

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

Julia Corá Segat 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.
8

An Environmental (LCA) and economic assessment (LCC) of on-farm and centralized alternatives for biogas production for two Swedish farms in Götene

Ouakrim, Abdelali January 2023 (has links)
Biogas production through anaerobic digestion is an important part towards the achievement of a bio-based and circular economy in Sweden. In fact, Swedish government proposed a strategy suggesting that biogas production should be increased from 2 TWh today to 7 TWh by 2030. Sweden has a large potential for biogas production from agricultural residues, not the least the Region Västra Götaland (RVG) where the stakeholders from the present study are located. The study explores the possibilities to use farm manure in co-digestion with deep bedding to produce biogas. The possibilities include two main alternatives for biogas production; mainly combined heat and power (CHP) to produce heat and electricity and biogas upgrading to produce bio-methane. The study took two existing organic farms in the municipality of Götene as a case study as well as an under-construction biogas plant by the company Gasum. The results of the present study also confirm that biogas could be a better option both economically and environmentally than fossil fuels. Additional results show that diesel consumption and energy prices are seen as hotspots that greatly influence both technical performance and economic profitability of biogas production. Another parameter is the geographical location of the studied system which could delimit or enhance the biogas production prospects depending on the proximity to gas grid or biogas unit. The aim of the study is to assess which of the studied alternatives is most profitable and has less environmental impacts; sending liquid manure to a biogas plant and receiving liquid fertilizer in exchange (centralized scenario) or invest in a biogas plant at the farm (on-farm scenario). A life cycle assessment (LCA) was conducted to compare environmental impacts of producing the equivalent of 1 MWh of biogas through on-farm plant and a biogas unit operated by the Finnish company Gasum. While a life cycle costing (LCC) was carried out considering a 10 year period with a 3% interest rate to analyze which of the two aforementioned options is more profitable for both farmers. Further this study aims to spur the interest of other scholars to further explore the potential of biogas/biomethane production within the agriculture sector and provide a better understanding of the different dynamics that impact the balance between energy provisions and the farm production process, and thus assist farmers to take part in the transition to a more renewable energy source.
9

Fontes orgânicas e Mineral: produção de culturas, alteração nos atributos químicos do solo e transferência de formas de nitrogênio e de fósforo / Organic and mineral sources: crop production, chemical change in the attributes of soil and forms of transfer of nitrogen and match

Ciancio, Nathalia Haydee Riveros 30 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The pig slurry, pig deep-litter and cattle slurry applied in soils under no-tillage can serve as a source of nutrients for crops, increasing the production of dry matter of shoots and grain production. This is because, successive applications in the long term tend to change the soil chemical properties making it favorable for the development of agricultural crops, if handled properly. Moreover, these applications continued on the same area can promote the accumulation of nutrients in cultivated soils. Thus, there may be the transport of nutrients such as nitrogen (N) and phosphorus (P) to aquatic environments through runoff and or percolation, causing environmental imbalances. This aim of this study was to analyze the influence of continuous application of organic and mineral nutrient sources on grain yield and nutrient accumulation in crops and evaluate the changes in soil chemical properties and the transfer of nitrogen and phosphorus runoff and percolation under no-tillage. For this, two studies were developed: Study I aimed to evaluate, in the long term, the distribution of nutrients in the soil profile and the productivity of grain crops and ground cover plants when subjected to successive applications of organic and mineral sources nutrients. This study was conducted in a Typic Hapludalf with pig slurry applications (PS), cattle slurry (CS), pig deep-litter (PL) and mineral fertilizers (NPK) before the implementation of each of the succession culture: corn/oats in the years 2009/2010; 2010/2011 and 2011/2012 and in the year 2012/13 black oat /black beans. The study II aimed to evaluate transfers of forms of N and P by the drained solution and percolated in the same area subjected to successive applications of organic and mineral nutrient sources managed under no-tillage. In this experiment, samples were collected drained and leached solution and determined the total N, P-soluble P-particulate and P-total. The results obtained demonstrate that the CSS provided increment, both in the production of grain and dry matter accumulation and apparent recovery of N, P and K of cultures. The highest dry matter production of cultivated species and applications of different organic sources of nutrients promoted increase in levels of soil organic matter while allowing an increase in soil pH. Also provided the increase in important soil properties, such as the P, K, Ca and Mg available in the soil, in relation to the use of traditional mineral fertilization. The data showed that successive applications provide greater total-N transfer, surface runoff and percolation in the soil under the application of DLS and CSS. The largest transfers of P were observed in treatments with application of DLS, DLB and CSS in drained and leached solution. Therefore, it is essential to constantly monitor the quantities of organic and mineral sources added in crops, as well as the losses of N and P incurred pursuant to excess and / or in the same area, as these parameters are relevant when it aims to productivity and sustainability of agro-ecosystems. / Os dejetos líquidos de suínos e bovinos e a cama sobreposta de suínos aplicadas em solos sob plantio direto podem servir como fonte de nutrientes às culturas agrícolas, incrementando a produção de matéria seca da parte aérea e a produtividade de grãos. Isso ocorre, pois as aplicações sucessivas em longo prazo tendem a alterar os atributos químicos do solo, tornando-o favorável para o desenvolvimento das culturas agrícolas, se manejado adequadamente. Por outro lado, essas aplicações continuadas sobre uma mesma área pode promover o acúmulo excessivo de nutrientes nos solos cultivados. Dessa forma, pode ocorrer o transporte de nutrientes, como o nitrogênio (N) e fósforo (P), para ambientes aquáticos por meio do escoamento superficial e/ou percolação, causando desequilíbrios ambientais. O presente estudo objetivou analisar a influência da aplicação continuada de fontes orgânicas e mineral de nutrientes sobre a produtividade de grãos e acúmulo de nutrientes em culturas, avaliar as alterações nos atributos químicos do solo e a transferência de nitrogênio e fósforo por escoamento superficial e percolação em um Argissolo sob sistema plantio direto. Para isso, foram desenvolvidos dois estudos: O Estudo I objetivou avaliar, a distribuição de nutrientes no perfil do solo e a produtividade das culturas de grãos e plantas de cobertura, quando submetido a aplicações sucessivas de fontes orgânicas e mineral de nutrientes. Este estudo foi desenvolvido em um Argissolo Vermelho Distrófico arênico com aplicações de dejeto líquido de suínos (DLS), cama sobreposta de suínos (CSS), dejeto líquido de bovinos (DLB) e adubação mineral (NPK) antes da implantação de cada cultura da sucessão: milho/aveia preta, nos anos de 2009/2010; 2010/2011 e 2011/2012 e no ano de 2012/13 feijão preto/aveia preta. Para as culturas de milho e feijão foi avaliada a produtividade de grãos e, para todas as culturas, foi determinada a produção de matéria seca da parte aérea e o acumulo de N, P e K no tecido vegetal. Em setembro de 2012, quando completou 12 aplicações das fontes orgânicas, amostras de solo foram coletadas nas camadas 0-2, 2-4, 4-6, 6-8, 8-10, 10-12, 12-14, 14-16, 16-18, 18-20, 20-25, 25-30, 30-35, 35-40, 40-50 e 50-60 cm. Determinou-se o valor de pH em água (relação 1:1), os teores disponíveis de P, Cu e Zn, teores trocáveis de K, Al, Ca e Mg e os teores de matéria orgânica do solo. Calculou-se a CTCpH7,0, a saturação por Al, a saturação por bases e a acidez potencial (H+Al). O estudo II visou avaliar as transferências de formas de N e P pela solução escoada e percolada na mesma área submetida às aplicações sucessivas de fontes orgânica e mineral de nutrientes manejado sob sistema plantio direto. Nesse experimento foram coletadas amostras de solução escoada e percolada e determinado os teores de N-mineral, P-solúvel, P-particulado e P-total. Os resultados demostram que a CSS proporcionou incremento, tanto na produtividade de grãos quanto de matéria seca, acúmulo e recuperação aparente de N, P e K das culturas. As maiores produções de matéria seca das espécies cultivadas e as aplicações das diferentes fontes orgânicas de nutrientes promoveram incremento nos teores da matéria orgânica do solo ao mesmo tempo que permitiu um aumento no pH do solo. Além disso, proporcionou o incremento em atributos importantes do solo, tais como: nos teores P, K, Ca e Mg disponíveis no solo, em relação ao uso da adubação mineral tradicional. Os dados mostraram que as aplicações sucessivas proporcionam maior transferência de N-mineral, por escoamento superficial e percolação no solo submetido à aplicação de DLS e CSS. As maiores transferências de P foram observadas nos tratamentos com aplicação de DLS, DLB e CSS na solução escoada e percolada. Portanto, é imprescindível o monitoramento constante das quantidades de fontes orgânicas e mineral adicionadas nas lavouras, assim como, das perdas de N e P ocasionadas pela aplicação em excesso e/ou na mesma área, já que esses parâmetros são relevantes quando se almeja produtividade e sustentabilidade dos agroecossistemas.
10

Modélisation de la stabilisation de la matière organique et des émissions gazeuses au cours du compostage d'effluents d'élevage. / Modeling organic matter stabilization and gaseous emissions during windrow composting of livestock effluents

Oudart, Didier 08 November 2013 (has links)
La variété des pratiques de compostage et les différences de nature des substrats modifient la vitesse de dégradation de la matière organique (MO), la qualité finale du compost produit et la part d'émissions sous forme de polluants gazeux. L'optimisation du procédé nécessite la prédiction de ces transformations ou la réalisation d'essais empiriques. Cette thèse analyse les interactions entre les processus biologiques, biochimiques, physico-chimiques et thermodynamiques majeurs à l'origine de la stabilisation de la MO et des émissions gazeuses de CO2, H2O, NH3, N2O. Elle se focalise sur le compostage par aération passive en andain d'effluents d'élevage. La méthode s'appuie sur la modélisation dynamique et des expérimentations. L'impact des interactions entre la biodégradabilité du carbone, la disponibilité de l'azote, l'humidité et la porosité, sur la cinétique et la stœchiométrie des émissions gazeuses est analysé à partir d’observations en conditions contrôlées et sur une plateforme de compostage. Les écarts de répétabilité faibles en conditions contrôlées deviennent élevés en conditions de reproductibilité sur le terrain. Un modèle dynamique de compostage a été développé simulant la stabilisation de la MO et les émissions de CO2, H2O, NH3, N2O. Il est composé de quatre modules simulant les cinétiques d'oxydation de la MO par une population microbienne, les échanges thermiques et l'aération passive, le transfert d'oxygène, les transformations de l'azote. Lors de la phase thermophile, le facteur limitant le plus rapidement l'organisation de la MO est la disponibilité de l'azote. L'abaissement de la porosité entraîne une diminution des pertes gazeuses par l'augmentation de l'organisation de la MO. Le fractionnement initial de la MO ainsi que la teneur initiale en biomasse microbienne sont les facteurs clés pour prédire les cinétiques d'organisation de la MO. La calibration des paramètres d’initialisation du modèle reste à améliorer / The variety of the practices and the differences in nature of the substrates modify the kinetics of degradation of organic matter (OM), the final quality of the produced compost and the fraction emitted as gaseous pollutants. To optimize the composting process, it is required to predict these transformations or to do some empirical test. This thesis analyzes the interactions between the main biological, biochemical, physicochemical and thermodynamic processes which explain the OM stabilization and the gaseous emissions of CO2, H2O, NH3, N2O. Focus is done on windrow composting with passive aeration. The method is based on dynamic semi-empirical modeling of the process and experimentations. The impact of the interactions between bioavailability of carbon and nitrogen, moisture and porosity, on the kinetics and the stoechiometry of the gaseous emissions is analyzed with data gathered in controlled conditions and on a commercial composting plant. The repeatability differences are small in controlled conditions but higher in field conditions. A dynamic model of composting was developed simulating the stabilization of OM as well as the emissions of CO2, H2O, NH3, N2O. This model is composed of four coupled modules which simulate the kinetics of oxidation of OM by a heterotrophic microbial population, the heat transfers leading to the passive aeration, the transfer of oxygen, the transformations of nitrogen. During the thermopilic phase, the first factor limiting the organization of OM is the availability of nitrogen. The decrease in porosity induces a reduction in the gas losses through the increase in the organization of OM. The initial OM fractionation and the initial microbial biomass are the key factors to predict the kinetics of organization of OM. The calibration of the specific parameters used for model initialization needs a further implementation

Page generated in 0.0437 seconds