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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.
11

Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical composting

Forgerini, Daniely 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo&reg. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo&reg. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
12

Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical composting

Daniely Forgerini 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo&reg. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo&reg. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
13

Efeito das larvas de besouro no processo de decomposi??o de esterco de coelho e produ??o de substratos org?nicos para mudas de hortali?as / Effect of the beetle?s larvae in the process of decomposition of rabbit manure and production of organic substrates to vegetable seedlings

PEREIRA, Claudete Martins da Silva 30 March 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-27T18:16:03Z No. of bitstreams: 1 2017 - Claudete Martins da Silva Pereira.pdf: 1419427 bytes, checksum: e45ce15f8c49fe9280e4eb8f4f21ca53 (MD5) / Made available in DSpace on 2018-09-27T18:16:03Z (GMT). No. of bitstreams: 1 2017 - Claudete Martins da Silva Pereira.pdf: 1419427 bytes, checksum: e45ce15f8c49fe9280e4eb8f4f21ca53 (MD5) Previous issue date: 2017-03-30 / The soil?s fertility and nutrient cycling are essential for agricultural production. Many organisms play a key role in the decomposition of organic matter present in nature. Among these organisms, more attention and research should be directed to the coprophagous insects. They transform agricultural residues in material rich in nutrients. Coleoptera families act in the fragmentation of decomposing organic matter (vegetal remains, rotten wood, straw, manure, among others), participating in the cycling of nutrients, but little is known about the humus produced by other species of the fauna of the soil beyond the earthworms. The objective of this work was to study compost from rabbit manure processed by beetle larvae under controlled conditions, and to analyze the potential of usage of this compost as substrate for lettuce seedlings production. To reach this goal, the study was accomplished in Embrapa Agrobiologia, Serop?dica (RJ), and it was divided in two phases. In the first chapter, the rabbit manure by beetle larvae and earthworms were incubated, aiming the compost production. During the course of the composting process, samples were taken at 0, 30, 60 and 90 days of incubation. In these samples the variables analyzed were: electrical conductivity (EC); pH; contents of N, P, K, Ca and Mg; and humic substances. In the second chapter the rabbit manure compost produced were evaluated as substrates for lettuce seedlings production. The following characteristics were evaluated: germination percentage, aerial part's height, number of leaves, production of fresh mass of aerial part and of the root, root volume and clod stability. The results indicated that the substrate of the cuniculture residue compost processed by cetoniinae larvae was as efficient as the substrate from vermicomposting, and the substrate commonly used in the experimental research site (Fazendinha km 47) for production of lettuce seedlings. / A fertilidade do solo e a ciclagem de nutrientes s?o fundamentais para a produ??o agr?cola. Muitos organismos exercem papel fundamental na decomposi??o da mat?ria org?nica presente na natureza. Dentre esses organismos, maior aten??o e pesquisa devem ser direcionadas aos insetos copr?fagos, por tamb?m transformarem res?duos da agropecu?ria, em material rico em nutrientes. As fam?lias de cole?pteros atuam na fragmenta??o da mat?ria org?nica em decomposi??o (restos vegetais, madeira podre, palha, estercos, entre outros), participando da ciclagem de nutrientes, por?m, pouco se conhece sobre o h?mus produzido por outras esp?cies da fauna do solo que n?o sejam as minhocas. O objetivo deste trabalho foi estudar a compostagem de esterco de coelho por larvas de besouro em condi??es controladas e analisar o potencial de uso do composto produzido como substrato para produ??o de mudas de alface. Visando alcan?ar este objetivo, este trabalho foi realizado na Embrapa Agrobiologia em Serop?dica, RJ, sendo dividido em duas etapas. No cap?tulo I, foi realizada a incuba??o de esterco de coelho por larvas de besouro e por minhocas, visando a produ??o do composto. Durante o decorrer do processo de compostagem, amostras foram coletadas aos 0, 30, 60 e 90 dias de incuba??o. Nessas amostras foram analisadas as seguintes vari?veis, condutividade el?trica (CE), pH, teores de N, P, K, Ca e Mg e subst?ncias h?micas. No cap?tulo 2, os compostos de esterco de coelho produzidos foram avaliados como substratos para a produ??o de mudas de alface. As seguintes caracter?sticas foram avaliadas: porcentagem de germina??o, altura da parte a?rea, n?mero de folhas, produ??o de massa fresca da parte a?rea e da raiz, volume de raiz e estabilidade do torr?o. Os resultados obtidos indicam que o substrato oriundo da compostagem de res?duos da cunicultura, realizada por larvas de cetoniinae, ? t?o eficiente quanto o substrato obtido atrav?s da vermicompostagem e o substrato comumente utilizado na Fazendinha km 47 para a produ??o de mudas de alface.
14

Vermicomposting of cod (Gadus morhua) offal mixed with sphagnum peat /

Decker, Stephanie J., January 2000 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2000. / Restricted until November 2001. Bibliography: leaves 97-104.
15

The performance of vermicompost filtration : an on-site domestic waste treatment system /

Taylor, Mike, January 2004 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2002. / Includes bibliography.
16

Optimization of the vermidegradation of cow dung – waste paper mixtures

Unuofin, Frank Oshioname January 2014 (has links)
Vermicomposting is an eco-friendly waste management strategy. Its successful performance necessitate that key functioning parameters like earthworm stocking density, nutrient enrichment be established for each target waste/waste mixture. One main target waste mixture in South Africa, and in the University of Fort Hare in particular is waste paper mixed with cow dung and rock phosphate (RP) for phosphorus (P) enrichment. This study was carried out to address the following specific objectives, to determine (i) the effect of Eisenia fetida stocking density on the bioconversion of cow dung waste paper mixtures enriched with rock phosphate, (ii) an optimum application rate of low grade South African Rock Phosphate and time required for efficient vermicomposting of cow dung-waste paper mixtures, and (iii) to determine if the phosphorus in RP is responsible for improved biodegradation during the vermicomposting of cow dung-waste paper mixtures. Results of this study revealed that bioconversion of cow dung waste paper mixtures enriched with RP was highly dependent on E. fetida stocking density and time. The stocking density of 12.5 g-worms kg-1 feedstock of the mixtures resulted in highest earthworm growth rate and humification of the waste mixture as reflected by a C: N ratio of < 12, polymerization index (PI) or humic acid/fulvic acid ratio of > 1.9, and a humification index of >13 for the cow dung waste paper mixtures. A germination test carried out also revealed that the resultant vermicompost had no inhibitory effect on the germination of tomato, carrot, and radish. Extractable P increased with stocking density up to 22.5 g-worm kg-1 feedstock, suggesting that for maximum P release from RP enriched wastes, a high stocking density should be considered. Informed by an earlier study which demonstrated that RP improved vermidegration, a follow up study was done to determine the optimum amount of rock phosphate necessary for efficient vermidegradation of cow dung waste paper mixtures while ensuring a phosphorus rich vermicompost. The results showed that addition of RP at rates ≤ 1% P as RP efficiently enhanced the bioconversion of cow dung waste paper mixtures as reflected by low C: N ratio, high polymerization index (PI), HI and HR used as maturity indicators for matured compost. Final vermicompost products obtained at minimum amounts of RP application rates resulted highly humified vermicompost with finer morphological structure, with no inhibitory effect on the germination of tomato, carrot, and radish similar to the ones obtained at higher RP rates. The findings suggest that 1%P as RP application rate is optimum for efficient vermidegradation of cow dung waste paper mixtures. Since P or Ca happen to be the most prevalent elements in most rock phosphate used for compost enrichment, a study was carried out to determine if P or Ca in RP is predominantly responsible for the improved biodegradation of cow-dung waste paper mixture observed during vermicomposting. Phosphorus sources in form of triple superphosphate (TSP), phosphoric acid (PHA) and Ca in form of calcium chloride (CaCl2) salt were compared with rock phosphate. The results from the study indicated that TSP, a water soluble P source, resulted in greater and faster degradation of the waste mixtures than RP while the Ca source had the least effect. With TSP incorporation the compost maturity C: N ratio of 12 was reached within 28 days while RP, PHA and CaCl2 needed 42, 56 and more than 56 days, respectively. The results indicated that P was largely responsible for the enhanced bioconversion of the waste mixtures. This appeared linked to the effect of P to stimulate microbial growth as reflected by higher microbial biomass carbon levels where water soluble P sources were applied. The C: N ratios of the final vermicomposts at day 56 were 10, 11.5, 13, 14, and 23 for TSP, RP,PHA, Control (No P added) and CaCl2 treatments, respectively. Although TSP gave superior superior performance, RP may still be the preferred additive in the vermicomposting of cow dung waste paper mixtures as it is cheaper and produces mature compost in a shorter period of 8 weeks. Generally, the results of this study have shown that the vemidegradation of cow dung waste paper mixtures can be optimized through adoption of an E. fetida stocking density of 12.5g- worm kg-1 and an RP incorporation rate of 1% P as RP. However, higher rates of RPincorporation may be adopted where final vermicomposts with higher P fertilizer value are desired. Phosphorus appears to be the RP constituent responsible for its ability to enhance the vermidegradation of cow dung waste paper mixtures. Future studies should explore the effectiveness of other P-bearing minerals for their effectiveness in enhancing vemidegradation.
17

Effect of vermicompost on growth and yield of cabbage (Brassica oleraceae var. capitata)

Lesufi, Ramadimetse Rebone January 2015 (has links)
Thesis ((MSc. Agriculture (Agronomy)) -- University of Limpopo, 2015 / An experiment was conducted to evaluate the effect of vermicompost on cabbage growth and yield. Vermicompost (VC) was applied at 2500 kg/ha and was compared to one organic {vita grow (VG) [N:P:K 2:3:2 (16)] and one chemical fertiliser (CF) (N:P:K 2:3:2(22)]} which were both applied at 1500 kg/ha. The other treatments were prepared as mixtures of the three fertilisers (i.e. vermicompost and vita grow; vita grow and chemical fertiliser as well as vermicompost and chemical fertiliser) at 50% recommended rate, with no fertiliser treatment as a control. The trial was laid out in a randomised complete block design with three replicates. Chemical fertiliser achieved the highest chlorophyll content (80.6 nmol/mg) which was significantly higher than the other treatments. Vermicompost and the control had the least chlorophyll content at 58.6 and 55.8 nmol/mg, respectively. VC+VG, CF and CF+VC achieved the highest numbers of marketable heads while the control had the least. VC+VG, CF and CF+VC had more than 60% of the plants producing marketable heads whilst VC and VG had less than 40% of the plants producing marketable heads. The control only had 19.93% of the plants producing marketable heads. Range of marketable heads ranged from 2.82 t/ha for the control to 12.7 t/ha for CF. VC+VG, CF and CF+VC achieved marketable yields above 10.0 t/ha.VC and VG achieved 5.45 and 8.28 t/ha. The results thus show that use of chemical fertiliser or the combinations of VC and VG and that of CF and VC are the ones that can be recommended for cabbage production. Key words: vermicompost, growth, yield, cabbage, fertiliser
18

Rural Organic Waste Treatment System Design and Analysis-Based on Vermicomposting Technology

Li, Xiangyu January 2011 (has links)
Rural organic waste is becoming a problem in developing countries due to lack of financial and technological support comparing with situation in urban area. A rural organic waste treatment system was designed utilizing vermicomposting technology to treat organic waste generated in rural area. ROWATS is a theoretical facility to treat rural organic wastes in Shandong Peninsula, China where cow dung and domestic organic waste are disposed freely. Theoretical demonstration shows that ROWATS can treat 1,200 kg of organic wastes daily and produce around 20 tons of vermicast and 800 kg of earthworm body and larvae every month. Products of ROWATS can be used as soil fertilizer, fish bait, and biopharmaceuticals and so on. Sufficient financial support is the most important factor for ROWATS in rural area. Cost-Benefit Analysis and Net Present Value Calculation were made to assess the feasibility of ROWATS. Results showed that ROWATS is a profitable project in terms of 2 years and 5 years. Sensitivity Analysis is also applied to evaluate the impact of different factors variation on ROWATS, of which result shows price and productivity variation of products can affect the profit of ROWATS more significantly comparing with cost changes. Hence, operator should keep products production stable. ROWATS can also improve the environmental and hygienic impacts through reduction of leakages, odor and bacteria and virus infection from flies, mosquitoes and other poisonous species.
19

Recycling Aquacultural Waste through Horticultural Greenhouse Production as a Resource Recovery Approach

Nair, Divya Sreelatha 09 March 2006 (has links)
For intensive production systems like the Blue Ridge Aquaculture (BRA), based in Martinsville, VA, there are significant economic incentives to reuse the waste by diverting it into a cropping system that would increase the total productivity and total resource-reuse efficiency, and decrease the environmental, ecological, and financial costs of aquacultural waste disposal. In order to facilitate the reuse of effluent from the tilapia production at the BRA, a green house was developed. On this site, sludge waste from recirculating aquaculture was separated and composted using a vermicomposting technique and the resulting compost was utilized as an amendment to conventional greenhouse potting mixes. These aquacultural waste products were compared to conventional greenhouse culture of a common ornamental annual plant. It was hypothesized that (1) vermicomposted aquaculture sludge would increase the growth of plants over conventional greenhouse potting mixes, and (2) recycled aquacultural wastewater can serve as a quality source of irrigation water, and plant response would differ with irrigation method. Plant growth and 11 out of 12 plant tissue nutrients were greater when compost was increased in the substrate. Plant root growth and 3 out of 12 tissue nutrients were increased when irrigated with wastewater. Plant shoot mass and total mass was greater when irrigated by ebb and flow irrigation compared to overhead mist irrigation, and 4 out of 12 tissue nutrients were greater when irrigated with mist irrigation. Overall plant performance was greatest with 15% vermicomposted sludge in the substrate and watered with wastewater by ebb and flow irrigation. / Master of Science
20

蚯蚓堆肥: 創造城市貧民經濟收入 / VERMIPOWER: Creating a Source of Income in Urban Slums

睿愛德, Rivera, Eduardo Unknown Date (has links)
Millions and millions of people in urban slums around the world are waiting for an opportunity to build an effective business in generating good source of income. They also wish to have an opportunity to change their lives and to be able to work, to buy food, to send their children to school, and to stop being sick. A group of people, that eventually became good friends, in National Chengchi University while studying in the International Masters in Business Administration and the Executive Masters in Business Administration respectively, have decided to embark in an adventure that aim to impact in a positive way the lives of millions of slum dwellers worldwide through a social enterprise. They established a project called VERMIPOWER which intent to provide a source of income for slum dwellers as well as to enhance the living conditions global slum areas. Social enterprises are a profit generated business that looks for social, cultural, economic, and environmental outcomes. These enterprises are financially self-sufficient. The social enterprise that VERMIPOWER aspires to be, plan to have positive impacts on many factors within urban slums; from directly impacting people’s lives to helping the environment by utilizing elements from within the urban slums. The company is built on the idea that the urban slums have items that can be used for a resource recovery process. Red worms will be needed as well as food waste. Red worms are a perfect fertilizer producer when eating food waste in a process known as vermicomposting. Interesting enough, red worms, while producing vermicompost, reproduce at an accelerated rate providing two interesting sources of income for slum dwellers, both red worms and vermicompost. Vermicompost can be used in farms, gardens and red worms can be sold in bait shops, zoos, etc. As the saying goes, one man’s trash is another man’s treasure, the company will turn trash into treasure, literally. And with the help of third party corporations it will be possible as well to fulfill the ultimate goal, which is creating a source of income for millions of slum dwellers across the world.

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