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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.
1

Effects of liming on microbial activity and N mineralization in broiler manure-amended soils from Bizana, Eastern Cape, South Africa

Jezile, G, Westfall, D, Peterson, G, Child, DR, Turner, DP, Van Averbeke, W 25 November 2008 (has links)
A laboratory incubation study was conducted to determine the effects of liming on microbial activity and N mineralization in two Bizana soils amended with broiler manure. The experimental layout was a 4 x 3 complete factorial experiment with three replicates, arranged in a randomized design. Soil pH, CO2 evolution, and mineral N concentration were measured. After 56 days the soil pH ranged from 4.50 to 5.74 and 4.99 to 5.94, in the Magusheni and Nikwe soils, respectively. The effect of liming on microbial activity and N mineralization differed between the soils. In the Nikwe soil (acid saturation 4.0%), microbial activity and N mineralization increased as the rate of broiler manure application was raised, but liming had no effect. In the Magusheni soil (acid saturation 25%), microbial activity increased as both lime and chicken manure application rates increased, but liming reduced N mineralization, suggesting N immobilization was being driven by an active microbial population in the limed soils. The rates of lime and/or chicken manure application, percentage Ca2+ and soil acid saturation were important factors influencing microbial activity and N mineralization, but the effect of soil pH on N mineralization was not evident in either of the soils.
2

The Effect of Different Methods of Handling Chicken Manure on the Viability of Weed Seed

Stoker, Golden L. 01 May 1938 (has links)
It is well known that weeds spread and are perpetuated by means of seed and vegetative reproduction. The seeds in turn are spread by various agencies such as wind, water, animals and man. These agencies are aided by especially adapted seed mechanisms for dissemination.
3

Anaerobic fermentation of rice straw and chicken manure to carboxylic acids

Agbogbo, Frank Kwesi 25 April 2007 (has links)
In this work, 80% lime-treated rice straw and 20% lime-treated chicken manure were used as substrates in rotary fermentors. Countercurrent fermentation was performed at various volatile solid loading rates (VSLR) and liquid residence times (LRT). The highest acid productivity of 1.69 g/(L·d) was at a total acid concentration of 32.4 g/L. The highest conversion and yield were 0.692 g VS digested/g VS fed and 0.29 g total acids/g VS fed, respectively. The continuum particle distribution model (CPDM) was used to predict product concentrations at various VSLR and LRT. CPDM predicted the experimental total acid concentration and conversion at an average error of 6.41% and 6.55%, respectively. A fixed-bed fermentation system was designed to perform pretreatment and fermentation in the same unit. High product concentrations (~48 g/L) as well as high conversions (0.741 g VS digested/g VS fed, F4, Train B) were obtained from the same fermentor. CPDM was extended to predict product concentrations in the fixed-bed fermentation system. The model gave a good estimate of the product concentrations and retention time. After biomass fermentation, the residue can be combusted to generate heat. For pretreatment purposes, the use of ash can replace lime. A study was performed using ash as a potential pretreatment agent. Ash from raw poplar wood was effective in pretreating poplar wood; however, ash from bagasse fermentation residues was not useful in pretreating bagasse. Previous modeling studies indicate that a conversion of 95% could be achieved with bagasse using countercurrent fermentation. Because lignin constitutes 13% of the dry weight of bagasse, this means lignin would have to be digested to obtain a conversion of 95%. Experiments on the fermentation of enzymatically liberated lignin from both poplar wood and bagasse do not show that solubilized lignin was fermented to organic acids by using a mixed culture of marine microorganisms. Two buffer systems (ammonium bicarbonate and calcium carbonate) were used to compare product concentrations of carboxylic acid fermentations using office paper and chicken manure. It has been demonstrated that the total product concentration using ammonium bicarbonate is almost double the product concentration using calcium carbonate.
4

Experimental studies of ash transformation processes in thermochemical conversion of P-rich biomass and sludge / Experimentella studier av asktransformationsprocesser vid termokemisk omvandling av P-rik biomassa och slam

Häggström, Gustav January 2020 (has links)
The efficient use of resources and sustainable recovery of various materials are important to minimize the anthropogenic impact on the climate and environment. One such resource is the phosphorus present in manure and sewage sludge. Various technologies are currently being developed to recover the phosphorus for the use of fertilizers in agricultural applications. Thermochemical conversion presents an opportunity to recover energy from these materials. At the same time, elements can be recovered in ash fractions, potentially harmful organic substances can be destroyed and heavy metals fractionated from the P. Mono-combustion of sewage sludge mainly produce apatite, which is not plant available and useful for fertilization. Co-combustion/-gasification with other fuels enables modification of ash transformation pathways and also remedy potential problems, such as bed agglomeration, associated with e.g. agricultural residues used as fuels. This thesis aims to increase the current knowledge in ash transformation of phosphorus-rich materials in cocombustion/-gasification with woody and agricultural fuels in process temperatures relevant for fluidized bed systems. The work focuses on i) possibility for formation of plant-available K-bearing phosphates ii) the effect of fuel ash composition and chemical association of P in the fuel on the distribution and speciation of P and iii) interaction of P-rich ash with bed material in fluidized beds. Experiments were carried out in bench-scale bubbling fluidized bed (BFB), macro-TGA (thermogravimetric analysis) combustion reactors and a dual fluidized bed (DFB) gasification reactor. Fuels studied were mixtures of chicken litter together with wheat straw and bark, and mixtures of digested sewage sludge combined with wheat straw and sunflower husk. Ash fraction and bed materials were collected and analyzed using ICP-OES/MS, SEM-EDS and XRD techniques. For the mixture of chicken litter and K- and Si-rich wheat straw, combusted in BFB, P and Si together with K and Ca formed homogeneous ash particles with large amounts of potentially amorphous iv content. A similar behavior was observed in sewage sludge and wheat straw mixtures where P and Si were likely present in a melt that is amorphous after extraction. In addition to these particles, P was also found in crystalline compounds such as hydroxyapatite, whitlockite and CaKPO4. For mixtures with Ca-rich bark, most of the phosphate formed was in the form of hydroxyapatite. In the interaction of ash with bed material, P captures Ca and K in phosphates, decreasing the interactions of these elements with the bed material, and thus can decrease the risk for bed agglomeration. The findings show that it is possible to modify the ash transformation of P towards K-bearing phosphates by co-combustion. Furthermore, they suggest that it is possible to recover most of the phosphorus in coarse ash fractions through co-combustion of P-rich materials with agricultural fuels. This means that P and volatile heavy metals can be separated into different ash fractions. This also increases the possibility of utilizing existing boilers for recovery of P as well as increased their flexibility to different fuels. To further validate the agricultural value of the produced ashes, plant growth studies have to be performed.
5

Propriedades físicas e químicas de um latossolo vermelho, cultivado com feijão e algodão, sob diferentes sistemas de preparo, adubações e plantas de cobertura /

Moreti, Dolorice. January 2002 (has links)
Orientador: Marlene Cristina Alves / Banca: Ronaldo Severiano Berton / Banca: Luiz Malcolm Mano de Mello / Resumo: O solo é um dos recursos de fundamental importância para a produção de alimentos. Sua conservação e recuperação, quando é visada a manutenção de sua qualidade, são primordiais para garantir o futuro das próximas gerações. O presente trabalho foi conduzido na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Engenharia de Ilha Solteira- SP, localizada no município de Selvíria-MS, durante o ano agrícola 2001/02. O objetivo foi verificar as alterações de algumas propriedades físicas e químicas de um LATOSSOLO VERMELHO de cerrado, sob as adubações orgânica e mineral, plantas de cobertura estabelecidas nos sistemas de plantio direto e convencional, e cultivado com o feijão de inverno e algodão. O delineamento utilizado foi em blocos casualizados com parcelas subdivididas. Nas parcelas foram instalados 2 tratamentos referentes aos preparos do solo, sendo o plantio direto e o preparo convencional. Nas subparcelas foram empregados 6 tratamentos, referentes às adubações e plantas de cobertura, sendo: esterco de galinha, esterco de galinha + ½ da adubação mineral recomendada, adubação mineral, crotalária, milheto e testemunha. Foram realizadas as seguintes análises físicas do solo: macroporosidade, microporosidade, porosidade total e densidade do solo As análises químicas foram para fins de fertilidade. Em relação às plantas, estudou-se: produção de grãos e matéria seca de feijão (Phaseolus vulgaris), produção de algodão em caroço (Gossypium hirsutum) e produção de matéria seca das plantas de cobertura. As coletas do solo destinado às análises foram realizadas nas profundidades de 0,00-0,10 m e 0,10-0,20 m. Os sistemas de preparo do solo, plantas de cobertura e os adubos não alteraram as propriedades físicas do solo. Os adubos e as plantas de cobertura interferiram nas propriedades químicas do solo, melhorando os teores dos seus... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: Soil is a resource of fundamental importance for the food production. Its conservation and recovery, when the objective is the quality maintenance, are very important to certify the future of next generations. This research was made in the Experimental Farm of Faculdade de Engenharia de Ilha Solteira, Ilha Solteira County, State of São Paulo during the agricultural year of 2001/02. The objective was to verify the alterations of some physical and chemical properties of a RED LATOSOL of Brazilian's Savannah under organic and mineral fertilizations, covering plants in no tillage and conventional tillage systems, and with bean and cotton crops. The experimental design was A randomized complete blocks with split-plots. In the plots were installed 2 treatments regarding the preparations of soil (no tillage and conventional tillage). In the subplots were installed 6 treatments which were: chicken manure fertilizer, chicken manure fertilizer + half of the recommended mineral fertilization, mineral fertilizations, Crotalaria juncea, Pennisetum americanum and control. The following soil physical analysis were made: macroporosity, microporosity, total porosity and bulk density. The chemical analysis were made to evaluete soil fertility. In relation the plants were: grain yield and plant dry matter of bean (Phaseolus vulgaris L), cotton yield (Gossypium hirsutum) and dry matter production of the covering plants. Soil samples were collected at depths of 0.00-0.10 m and 0.10-0.20 m. Soil management systems, covering plants and fertilizers affected the bean and cotton productivities, in which the no tillage system, showed higher productivities. In relation to the covering plants, the Pennisetum showed higher productivities of cotton. In respect to the fertilizers, the treatments with chicken fertilizer and chicken fertilizer + half of the recommended mineral provided higher productivities for bean and cotton crops. / Mestre
6

Efeito de adubação orgânica e mineral e culturas de entressafra na cultura da soja (Glycine max (L) Merrill) no sistema plantio direto

Zuim, Carlos Eduardo [UNESP] 05 September 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-09-05Bitstream added on 2014-06-13T19:39:09Z : No. of bitstreams: 1 zuim_ce_me_ilha.pdf: 206454 bytes, checksum: 21d45110bfb35795b4aee587ba2a4496 (MD5) / Universidade Estadual Paulista (UNESP) / A busca pela qualidade do solo como base de sustentação do sistema de produção, tem aumentado o desafio de compreender um sistema que, além de reduzir sensivelmente a degradação do meio ambiente, pode permitir maior retorno econômico ao agricultor. Nesse sentido o presente trabalho foi desenvolvido no período de abril de 2005 a abril de 2006, com o objetivo de avaliar na cultura da soja, no sistema de plantio direto, o efeito de diferentes culturas de cobertura e presença ou ausência de adubação orgânica e mineral. O trabalho foi desenvolvido no município de Guararapes-SP (50°39’W, 21°09’S e 412 m de altitude aproximadamente) em um Latossolo Vermelho amarelo, com textura média, sendo cultivado com culturas anuais a partir de 1993. O delineamento experimental utilizado foi o em blocos casualizados com 4 repetições, com os tratamentos dispostos em um esquema fatorial 5x2x2, ou seja, 5 culturas de cobertura (milho, milheto, sorgo, braquiária e mamona), cultivadas no período de outono/inverno, na presença e ausência de adubação orgânica (11.512 kg/ha de esterco de galinha), sendo semeado em sucessão, a cultura da soja, cultivar MGBR 46 (Conquista), na presença ou ausência de adubação mineral (500 kg/ha da fórmula 02-20-15). As culturas de cobertura e a soja foram irrigadas pelo sistema pivô central. As avaliações constaram da produção de massa seca das culturas de cobertura, estado nutricional da soja no florescimento pleno, características agronômicas e produção de grãos da soja e características químicas do solo, em diferentes profundidades, após o cultivo da soja. Através dos resultados obtidos, verificou-se que o milho apresentou maior produção de massa seca como cultura de cobertura, mas todas as... / The search for the soil quality as sustentation base of production system, has stimulated the challenge to understand a system that, beyond sensibly reducing the environment degradation, may allows greater economic return to the farmer. Thus, the present work was developed in the period of April 2005 to April 2006, with the objective to evaluate in soybean crop, in no tillage system, the effect of different cover crops and presence or absence of organic and mineral fertilization. The work was developed at the municipal district of Guararapes, State of São Paulo (50°39' W, 21°09' S and 412 m altitude approximately) in a Typic Haplustox, with sandy texture, being cultivated with annual crops since 1993. The exeprimental design used was randomized blocks with four replications, with treatments disposed in a 5x2x2 factorial scheme, i.e., five cover crops (corn, millet, sorghum, braquiaria grass and castor bean), cultivated in the autumn/winter period, in presence and absence of organic fertilization (11,512 kg ha-1 of chicken manure fertilizer), being sowedin succession of soybean crop, MGBR 46 cultivar, in presence or absence of mineral fertilization (500 kg ha-1 of 02-20-15 formula). The cover cultures and soybean had been irrigated by center pivot irrigation systems.The evaluations was cover crops dry matter production, nutritional status in flowering, agronomic characteristics and soybean grain production, soil chemical characteristis, in different depths, after soybean. Through the obtained results, it verified that the corn presents greater dry matter production as cover crop, but all the evaluated cover crops are adjusted to precede soybean; organic fertilization increases cover crop dry matter production, beyond provided significant P, Ca and K increases in 0 to 0.05 and 0.05 to 0.10 m depth and P and K in 0.10 to 0.20 m depth; ...(Complete abstract click electronic access below)
7

Propriedades físicas e químicas de um latossolo vermelho, cultivado com feijão e algodão, sob diferentes sistemas de preparo, adubações e plantas de cobertura

Moreti, Dolorice [UNESP] 13 December 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-12-13Bitstream added on 2014-06-13T18:39:47Z : No. of bitstreams: 1 moreti_d_me_ilha.pdf: 1425402 bytes, checksum: 8bd940b9b29695b569162022310de606 (MD5) / O solo é um dos recursos de fundamental importância para a produção de alimentos. Sua conservação e recuperação, quando é visada a manutenção de sua qualidade, são primordiais para garantir o futuro das próximas gerações. O presente trabalho foi conduzido na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Engenharia de Ilha Solteira- SP, localizada no município de Selvíria-MS, durante o ano agrícola 2001/02. O objetivo foi verificar as alterações de algumas propriedades físicas e químicas de um LATOSSOLO VERMELHO de cerrado, sob as adubações orgânica e mineral, plantas de cobertura estabelecidas nos sistemas de plantio direto e convencional, e cultivado com o feijão de inverno e algodão. O delineamento utilizado foi em blocos casualizados com parcelas subdivididas. Nas parcelas foram instalados 2 tratamentos referentes aos preparos do solo, sendo o plantio direto e o preparo convencional. Nas subparcelas foram empregados 6 tratamentos, referentes às adubações e plantas de cobertura, sendo: esterco de galinha, esterco de galinha + ½ da adubação mineral recomendada, adubação mineral, crotalária, milheto e testemunha. Foram realizadas as seguintes análises físicas do solo: macroporosidade, microporosidade, porosidade total e densidade do solo As análises químicas foram para fins de fertilidade. Em relação às plantas, estudou-se: produção de grãos e matéria seca de feijão (Phaseolus vulgaris), produção de algodão em caroço (Gossypium hirsutum) e produção de matéria seca das plantas de cobertura. As coletas do solo destinado às análises foram realizadas nas profundidades de 0,00-0,10 m e 0,10-0,20 m. Os sistemas de preparo do solo, plantas de cobertura e os adubos não alteraram as propriedades físicas do solo. Os adubos e as plantas de cobertura interferiram nas propriedades químicas do solo, melhorando os teores dos seus... . / Soil is a resource of fundamental importance for the food production. Its conservation and recovery, when the objective is the quality maintenance, are very important to certify the future of next generations. This research was made in the Experimental Farm of Faculdade de Engenharia de Ilha Solteira, Ilha Solteira County, State of São Paulo during the agricultural year of 2001/02. The objective was to verify the alterations of some physical and chemical properties of a RED LATOSOL of Brazilian’s Savannah under organic and mineral fertilizations, covering plants in no tillage and conventional tillage systems, and with bean and cotton crops. The experimental design was A randomized complete blocks with split-plots. In the plots were installed 2 treatments regarding the preparations of soil (no tillage and conventional tillage). In the subplots were installed 6 treatments which were: chicken manure fertilizer, chicken manure fertilizer + half of the recommended mineral fertilization, mineral fertilizations, Crotalaria juncea, Pennisetum americanum and control. The following soil physical analysis were made: macroporosity, microporosity, total porosity and bulk density. The chemical analysis were made to evaluete soil fertility. In relation the plants were: grain yield and plant dry matter of bean (Phaseolus vulgaris L), cotton yield (Gossypium hirsutum) and dry matter production of the covering plants. Soil samples were collected at depths of 0.00-0.10 m and 0.10-0.20 m. Soil management systems, covering plants and fertilizers affected the bean and cotton productivities, in which the no tillage system, showed higher productivities. In relation to the covering plants, the Pennisetum showed higher productivities of cotton. In respect to the fertilizers, the treatments with chicken fertilizer and chicken fertilizer + half of the recommended mineral provided higher productivities for bean and cotton crops.
8

Possible Drivers in Endophyte Diversity and Transmission in the Tomato Plant Bacterial Microbiome

Vazquez, Ana M. January 2020 (has links)
No description available.
9

Efeito de adubação orgânica e mineral e culturas de entressafra na cultura da soja (Glycine max (L) Merrill) no sistema plantio direto /

Zuim, Carlos Eduardo. January 2007 (has links)
Orientador: Edson Lazarini / Banca: Marco Eustáquio de Sá / Banca: Edson Luiz Mendes Coutinho / Resumo: A busca pela qualidade do solo como base de sustentação do sistema de produção, tem aumentado o desafio de compreender um sistema que, além de reduzir sensivelmente a degradação do meio ambiente, pode permitir maior retorno econômico ao agricultor. Nesse sentido o presente trabalho foi desenvolvido no período de abril de 2005 a abril de 2006, com o objetivo de avaliar na cultura da soja, no sistema de plantio direto, o efeito de diferentes culturas de cobertura e presença ou ausência de adubação orgânica e mineral. O trabalho foi desenvolvido no município de Guararapes-SP (50°39'W, 21°09'S e 412 m de altitude aproximadamente) em um Latossolo Vermelho amarelo, com textura média, sendo cultivado com culturas anuais a partir de 1993. O delineamento experimental utilizado foi o em blocos casualizados com 4 repetições, com os tratamentos dispostos em um esquema fatorial 5x2x2, ou seja, 5 culturas de cobertura (milho, milheto, sorgo, braquiária e mamona), cultivadas no período de outono/inverno, na presença e ausência de adubação orgânica (11.512 kg/ha de esterco de galinha), sendo semeado em sucessão, a cultura da soja, cultivar MGBR 46 (Conquista), na presença ou ausência de adubação mineral (500 kg/ha da fórmula 02-20-15). As culturas de cobertura e a soja foram irrigadas pelo sistema pivô central. As avaliações constaram da produção de massa seca das culturas de cobertura, estado nutricional da soja no florescimento pleno, características agronômicas e produção de grãos da soja e características químicas do solo, em diferentes profundidades, após o cultivo da soja. Através dos resultados obtidos, verificou-se que o milho apresentou maior produção de massa seca como cultura de cobertura, mas todas as ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The search for the soil quality as sustentation base of production system, has stimulated the challenge to understand a system that, beyond sensibly reducing the environment degradation, may allows greater economic return to the farmer. Thus, the present work was developed in the period of April 2005 to April 2006, with the objective to evaluate in soybean crop, in no tillage system, the effect of different cover crops and presence or absence of organic and mineral fertilization. The work was developed at the municipal district of Guararapes, State of São Paulo (50°39' W, 21°09' S and 412 m altitude approximately) in a Typic Haplustox, with sandy texture, being cultivated with annual crops since 1993. The exeprimental design used was randomized blocks with four replications, with treatments disposed in a 5x2x2 factorial scheme, i.e., five cover crops (corn, millet, sorghum, braquiaria grass and castor bean), cultivated in the autumn/winter period, in presence and absence of organic fertilization (11,512 kg ha-1 of chicken manure fertilizer), being sowedin succession of soybean crop, MGBR 46 cultivar, in presence or absence of mineral fertilization (500 kg ha-1 of 02-20-15 formula). The cover cultures and soybean had been irrigated by center pivot irrigation systems.The evaluations was cover crops dry matter production, nutritional status in flowering, agronomic characteristics and soybean grain production, soil chemical characteristis, in different depths, after soybean. Through the obtained results, it verified that the corn presents greater dry matter production as cover crop, but all the evaluated cover crops are adjusted to precede soybean; organic fertilization increases cover crop dry matter production, beyond provided significant P, Ca and K increases in 0 to 0.05 and 0.05 to 0.10 m depth and P and K in 0.10 to 0.20 m depth; ...(Complete abstract click electronic access below) / Mestre

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