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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.
171

Properties of an Orthic Black Chernozem after 5 years of liquid and solid pig manure applications to annual and perennial crops

Adesanya, Theresa 09 January 2016 (has links)
Soil physical and chemical properties determine a soil's crop production potential and the sustainability of a production system. The objective of this study was to determine the effect of solid and liquid pig manure application on the physical and chemical properties of soil after 5 years of manure application. Solid pig manure increased saturated hydraulic conductivity (Ksat) by 110%, aggregate stability by 30%, available and total phosphorus by 471% and 52% respectively, available nitrogen by 38%, organic carbon by 29% and exchangeable K by 308%, and reduced soil bulk density by 14%. Liquid pig manure (LPM) also increased aggregate stability by 21%, exchangeable K by 45%, available P and total P by 258% and 27%, respectively and, reduced bulk density by 6%. An important finding was the 33% decrease in the concentration of exchangeable Ca in LPM-amended soils. Significant manure by cropping system interaction was also obtained for water retention parameters and available water, total nitrogen and electrical conductivity. There was no effect of pig manure on pH and exchangeable Mg concentrations. Soils under perennial vegetation had 31% greater Ksat, 26% increase in available N, 31% greater available P, 15% greater total P and 12% lower bulk density compared with those under annual crops. Our results show that SPM has a potential as a better organic amendment in improving physical and chemical properties of surface soils. / February 2016
172

Análise da viabilidade da reciclagem de dejetos de bovinos com tratamento biológico, em sistema intensivo de produção de leite

Campos, Aloísio Torres de [UNESP] 26 August 1997 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:38Z (GMT). No. of bitstreams: 0 Previous issue date: 1997-08-26Bitstream added on 2014-06-13T19:20:55Z : No. of bitstreams: 1 campos_at_dr_botfca.pdf: 540232 bytes, checksum: a35a4cac7aab273cfb7389bf3d329beb (MD5) / O objetivo deste trabalho foi avaliar o desempenho econômico e a eficiência do tratamento biológico aeróbio, na redução e estabilização da matéria orgânica biodegradável, de dejetos líquidos de bovinos, visando a sua reciclagem na limpeza hidráulica das instalações dos animais (free stall) e sua posterior utilização nas áreas de produção de forragem. O trabalho foi desenvolvido nas instalações do Sistema Intensivo de Produção de Leite (SIPL) da Embrapa - Centro Nacional de Pesquisa de Gado de Leite (CNPGL), situado no município de Coronel Pacheco, MG. Dois reatores com capacidade útil de 300 m3 cada um foram construídos para compor as unidades do processo de lodo ativado por batelada (LAB), com sistemas de aeração prolongada e intermitente. Esses reatores foram dimensionados para um tempo de detenção hidráulico de 24 dias, com diluição dos dejetos (fezes + urina) em água na proporção de 1:1. Em cada reator foi instalado um aerador-misturador submersível, regulados para períodos de aeração de nove minutos e não-aeração de 18 minutos. Uma motobomba de rotor aberto, com vazão de 60 m3/h, foi utilizada para reciclar o efluente tratado sobre os corredores dos galpões de confinamento free stall e promover a limpeza hidráulica dos dejetos, que retornam aos tanques de aeração por gravidade por meio de canaletas. A drenagem dos reatores foi processada por uma motobomba submersa, com vazão de 10 m3/h, conduzindo o efluente até as áreas de produção de forragem, por escoamento superficial. A caracterização dos efluentes foi realizada por meio de amostragens na entrada e no interior dos tanques de aeração, na saída da tubulação de irrigação e dos dejetos puros dos animais. Foram analisados os seguintes parâmetros: pH, temperatura, óleos e graxas, DBO total e solúvel, DQO total e solúvel, sólidos totais fixos e voláteis sólidos... / The objective of this work was to evaluate the economic performance and efficiency of an aerobic biological treatment on the reduction and stabilization of the biodegradable organic matter of the bovine liquid manure. This effluent will be recycled in the hydraulic cleaning of the facilities (free stalls) and utilized in grass production areas. This work was done in the Embrapa - milk production intensive system (MPIS) facilities in Coronel Pacheco, state of Minas Gerais. Two reactors with capacity of 300 m3 each were built as the activated sludge sequencing batch reactor (SBR) units with prolonged and intermittent aeration. These reactors were dimensioned for a hydraulic retention time of 24 days with wastewater (manure + urine) dilution in water on the proportion of 1:1. In each reactor a submerged aerator-mixer was installed, with aeration and non-aeration periods of 9 and 18 minutes, respectively. A motor-pumping equipment with open rotor and flow of 60 m3/h was used for recycling the treated effluent on the halls of the free stall confinement facilities and to promote hydraulic cleaning of the effluent that will return to the aeration tanks by gravity conducted by channel structures. The drainage of the reactors was processed by a submerged motor-pumping equipment with flow of 10 m3/h driving the effluent to the grass production areas throughout superficial disposal. Effluent characterization was done by collecting samples on the entrance and the interior of the tanks, on the gate of the irrigation tubulation and on the bovine pure manure. There were analyzed the following parameters: pH, temperature, oils and fats, soluble and total BOD, soluble and total COD, volatile and total solids, sedimented solids, ammonia and total nitrogen, potassium, total phosphorus, magnesium and sodium. To evaluate the economic performance of the system, the costs, the annual investments... (Complete abstract click electronic access below)
173

Uso de meio a base de esterco suíno no cultivo de Ankistrodesmus gracilis (Chlorophyta) em laboratório

Fioresi, Tatiana Betioli [UNESP] 16 April 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-16Bitstream added on 2014-06-13T19:55:57Z : No. of bitstreams: 1 fioresi_tb_me_jabo.pdf: 1222534 bytes, checksum: 8a60817f69089bec8947b5422404e7c7 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Um dos fatores importantes na criacao de larvas de peixes e o uso de alimento natural, tal como o fitoplancton, o qual pode ser cultivado em instalacoes especiais, a baixo custo com alto valor nutricional e elevada taxa de crescimento. Muitos fatores afetam o cultivo de algas como luz, nutrientes, temperatura e pH, sendo esses fatores complexos e dificeis de serem analisados separadamente, principalmente, as interacoes entre incidencia de luz e limitacao de nutrientes. Entretanto, a restricao a luz e mais impactante do que a limitacao de nutrientes, desde que a luz afeta diretamente a utilizacao dos compostos disponiveis no meio de cultura. Estudos tem sido enfatizados focalizando o cultivo de algas para a producao de alimento, utilizando-se meios alternativos como forma de baratear o custo de producao. O objetivo do presente trabalho foi avaliar e comparar o efeito do esterco suino no desenvolvimento de Ankistrodesmus gracilis, cultivada em laboratorio em dois meios: com esterco gin natura e esterco biodigerido. O experimento foi realizado no periodo de 22 dias nos volumes, de 2L e 250L, analisando a biologia, valor nutricional e a qualidade da agua do meio de cultura. Biovolume, teor de cinzas, comprimento total e concentracao de lipideos foram significativos (p<0,05) entre os volumes cultivados. O teor de proteina nao foi significativo (p>0,05) somente no meio com esterco biodigerido. As maiores densidades de A. gracilis foram observadas no volume de 2L, tendo a amostra cultivada em meio com esterco biodigerido ao longo do experimento maior densidade, com o pico ao redor do 5o dia, 6,2 x 107 celulas.ml-1. Ortofosfato, pH, alcalinidade, oxigenio dissolvido e temperatura da agua nao foram significativos (p>0,05) entre volumes e o nitrito nao foi detectado... / One of the most important factors in successfully fish rearing is probably the use of natural feed, such as phytoplankton, which may be grown in specially designed installations. So that high nutritional algae could be produced at low cost it is important to reach light production of algae and high growing rate. Many factors affect algae culture growth such as light, nutrients, temperature and pH since they directly involve algae density interactions between light incidence and limitation of nutrients are very complex and the effect of factor can not be analyzed separately. However, light restriction caused more impact than limiting of nutrients, since energy affected directly the utilization of the compounds available in the medium. Several studies focus on the culture of algae for food production through alternative methods to lower production costs. The effect of swine manure fertilization in the development of Ankistrodesmus gracilis was mensured on two medium: in natura and biodigested, during 22 days, in two volumes, 2L and 250L. The biology, nutritional value and water quality of culture medium were analyzed. Biovolume, ash rate, total length and lipids were higher (p<0.05) between treatments. Protein rate was different (p>0.05) only in the biodigested treatment. Highest A. gracilis densities were reported in 2L throughout the experiment the biodigested treatment had the highest density, 6.2 x 107 cells.ml-1, on the 5th day. Orthophosphate, pH, alkalinity, dissolved oxygen and water temperature were only different (p<0.05) between volumes. Nitrite, however, was not reported in the 2L volume treatment. Significant differences (p<0.05) between media were only reported for DBO5. Light demand was also... (Complete abstract, click electronic access below)
174

Manejo da adubação nitrogenada e utilização do nitrogênio (15N) pelo milho sob plantio direto com diferentes plantas de entressafra

Coutinho Neto, André Mendes [UNESP] 28 July 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-28Bitstream added on 2014-06-13T20:50:11Z : No. of bitstreams: 1 coutinhoneto_am_me_jabo.pdf: 296593 bytes, checksum: 6a6231cd7d56cc4c51fd35c56469fea9 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O aproveitamento do N pelo milho cultivado em sistema de plantio direto (SPD) é dependente da qualidade dos resíduos da cultura antecessora, que por sua vez podem promover diferenças na eficiência da adubação nitrogenada em função da época em que esta é realizada. Assim, objetivou-se avaliar as estratégias de aplicação do N e das plantas de entressafra na eficiência de utilização do N, no aproveitamento pelo milho do N das plantas de entressafra, previamente marcadas com 15N e na produção de milho cultivado em um solo argiloso, sob SPD (18 anos). O delineamento experimental utilizado foi em parcelas subdivididas com cinco tratamentos principais (estratégias de aplicação de N), dois tratamentos secundários (culturas de entressafra) e seis repetições dispostas em blocos casualizados. As estratégias de adubação (dose: 150 kg ha-1 de N - uréia) foram: 0 - 0 - 0; 20 - 80 - 50; 50 - 80 - 20; 150 - 0 - 0 e 0 - 80 - 70, sendo o primeiro número correspondente à dose de N (kg ha-1) aplicada em présemeadura e o segundo e terceiro números corresponderam às doses aplicadas quando as plantas de milho estavam nos estádios V4 e V8. As culturas de entressafra foram o milho e a soja. A aplicação de N aumentou a produtividade de grãos de milho, sendo esse efeito mais pronunciado quando a cultura de entressafra era a soja. Em termos de produção de grãos, as estratégias de aplicação de N foram equivalentes. O aproveitamento pelo milho, do N das plantas de entressafra, foi baixo, sendo que a maior parte desse nutriente permaneceu no solo. A maior eficiência de utilização do fertilizante nitrogenado pelo milho foi observada quando a dose total de N foi aplicada em pré-semeadura. O N não recuperado da uréia no sistema solo-planta foi, em média, de 46% / The utilization of N by maize grown on a no-tillage system (NT) depends on the quality of the residue of the crop winter, which may cause differences on the nitrogen fertilizer efficiency due to the time in which it is performed. Thus, this study aimed the evaluation of N application strategies and winter crops on N fertilizer use efficiency (NFUE), and the maize utilization of N from soybean and maize, both with 15N labeled, and the grain yield of maize grown in a clayey soil (Typic Acrustox), under NTS (18 years). The experimental design was a split-plot, with six replications in randomized complete blocks, where the main plot was the N application strategies and the split-plots was the winter crops (soybean and maize). The N application strategies (rate: 150 kg ha-1 of N - urea) were: (0 - 0 - 0), (20 - 80 -50), (50 - 80 - 20), (150 - 0 - 0) and (0 - 80 - 70), where the first number corresponds to the N rate applied on preplanting and the second and third ones correspond to the rate applied on top dressing when the plant presented, respectively, 4-leaf stage and 8- leaf stage. The N application increased the productivity of maize grains; these effects were more expressive when the crop winter was soybean. With regard to the grain production, the N application strategies were equivalent, inexistent significant differences among them. The N utilization by maize of the crop winter was low, and great part of such nutrient remained in the soil. The greatest Nitrogen Fertilizer Use Efficiency (NFUE) by maize was verified when the total N rate was applied on preplanting (NFUE = 38%). Regardless the N application strategy and the winter crop, the non recovered N (NRN) from the applied urea on the soil-plant system, was on average of 46% (69 kg ha-1 of N)
175

Uso de meio a base de esterco suíno no cultivo de Ankistrodesmus gracilis (Chlorophyta) em laboratório /

Fioresi, Tatiana Betioli. January 2007 (has links)
Orientador: Lúcia Helena Sipaúba-Tavares / Banca: Luiz Augusto do Amaral / Banca: Márcia Noélia Eler / Resumo: Um dos fatores importantes na criacao de larvas de peixes e o uso de alimento natural, tal como o fitoplancton, o qual pode ser cultivado em instalacoes especiais, a baixo custo com alto valor nutricional e elevada taxa de crescimento. Muitos fatores afetam o cultivo de algas como luz, nutrientes, temperatura e pH, sendo esses fatores complexos e dificeis de serem analisados separadamente, principalmente, as interacoes entre incidencia de luz e limitacao de nutrientes. Entretanto, a restricao a luz e mais impactante do que a limitacao de nutrientes, desde que a luz afeta diretamente a utilizacao dos compostos disponiveis no meio de cultura. Estudos tem sido enfatizados focalizando o cultivo de algas para a producao de alimento, utilizando-se meios alternativos como forma de baratear o custo de producao. O objetivo do presente trabalho foi avaliar e comparar o efeito do esterco suino no desenvolvimento de Ankistrodesmus gracilis, cultivada em laboratorio em dois meios: com esterco gin natura e esterco biodigerido. O experimento foi realizado no periodo de 22 dias nos volumes, de 2L e 250L, analisando a biologia, valor nutricional e a qualidade da agua do meio de cultura. Biovolume, teor de cinzas, comprimento total e concentracao de lipideos foram significativos (p<0,05) entre os volumes cultivados. O teor de proteina nao foi significativo (p>0,05) somente no meio com esterco biodigerido. As maiores densidades de A. gracilis foram observadas no volume de 2L, tendo a amostra cultivada em meio com esterco biodigerido ao longo do experimento maior densidade, com o pico ao redor do 5o dia, 6,2 x 107 celulas.ml-1. Ortofosfato, pH, alcalinidade, oxigenio dissolvido e temperatura da agua nao foram significativos (p>0,05) entre volumes e o nitrito nao foi detectado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: One of the most important factors in successfully fish rearing is probably the use of natural feed, such as phytoplankton, which may be grown in specially designed installations. So that high nutritional algae could be produced at low cost it is important to reach light production of algae and high growing rate. Many factors affect algae culture growth such as light, nutrients, temperature and pH since they directly involve algae density interactions between light incidence and limitation of nutrients are very complex and the effect of factor can not be analyzed separately. However, light restriction caused more impact than limiting of nutrients, since energy affected directly the utilization of the compounds available in the medium. Several studies focus on the culture of algae for food production through alternative methods to lower production costs. The effect of swine manure fertilization in the development of Ankistrodesmus gracilis was mensured on two medium: in natura and biodigested, during 22 days, in two volumes, 2L and 250L. The biology, nutritional value and water quality of culture medium were analyzed. Biovolume, ash rate, total length and lipids were higher (p<0.05) between treatments. Protein rate was different (p>0.05) only in the biodigested treatment. Highest A. gracilis densities were reported in 2L throughout the experiment the biodigested treatment had the highest density, 6.2 x 107 cells.ml-1, on the 5th day. Orthophosphate, pH, alkalinity, dissolved oxygen and water temperature were only different (p<0.05) between volumes. Nitrite, however, was not reported in the 2L volume treatment. Significant differences (p<0.05) between media were only reported for DBO5. Light demand was also... (Complete abstract, click electronic access below) / Mestre
176

Manejo da adubação nitrogenada e utilização do nitrogênio (15N) pelo milho sob plantio direto com diferentes plantas de entressafra /

Coutinho Neto, André Mendes. January 2011 (has links)
Resumo: O aproveitamento do N pelo milho cultivado em sistema de plantio direto (SPD) é dependente da qualidade dos resíduos da cultura antecessora, que por sua vez podem promover diferenças na eficiência da adubação nitrogenada em função da época em que esta é realizada. Assim, objetivou-se avaliar as estratégias de aplicação do N e das plantas de entressafra na eficiência de utilização do N, no aproveitamento pelo milho do N das plantas de entressafra, previamente marcadas com 15N e na produção de milho cultivado em um solo argiloso, sob SPD (18 anos). O delineamento experimental utilizado foi em parcelas subdivididas com cinco tratamentos principais (estratégias de aplicação de N), dois tratamentos secundários (culturas de entressafra) e seis repetições dispostas em blocos casualizados. As estratégias de adubação (dose: 150 kg ha-1 de N - uréia) foram: 0 - 0 - 0; 20 - 80 - 50; 50 - 80 - 20; 150 - 0 - 0 e 0 - 80 - 70, sendo o primeiro número correspondente à dose de N (kg ha-1) aplicada em présemeadura e o segundo e terceiro números corresponderam às doses aplicadas quando as plantas de milho estavam nos estádios V4 e V8. As culturas de entressafra foram o milho e a soja. A aplicação de N aumentou a produtividade de grãos de milho, sendo esse efeito mais pronunciado quando a cultura de entressafra era a soja. Em termos de produção de grãos, as estratégias de aplicação de N foram equivalentes. O aproveitamento pelo milho, do N das plantas de entressafra, foi baixo, sendo que a maior parte desse nutriente permaneceu no solo. A maior eficiência de utilização do fertilizante nitrogenado pelo milho foi observada quando a dose total de N foi aplicada em pré-semeadura. O N não recuperado da uréia no sistema solo-planta foi, em média, de 46% / Abstract: The utilization of N by maize grown on a no-tillage system (NT) depends on the quality of the residue of the crop winter, which may cause differences on the nitrogen fertilizer efficiency due to the time in which it is performed. Thus, this study aimed the evaluation of N application strategies and winter crops on N fertilizer use efficiency (NFUE), and the maize utilization of N from soybean and maize, both with 15N labeled, and the grain yield of maize grown in a clayey soil (Typic Acrustox), under NTS (18 years). The experimental design was a split-plot, with six replications in randomized complete blocks, where the main plot was the N application strategies and the split-plots was the winter crops (soybean and maize). The N application strategies (rate: 150 kg ha-1 of N - urea) were: (0 - 0 - 0), (20 - 80 -50), (50 - 80 - 20), (150 - 0 - 0) and (0 - 80 - 70), where the first number corresponds to the N rate applied on preplanting and the second and third ones correspond to the rate applied on top dressing when the plant presented, respectively, 4-leaf stage and 8- leaf stage. The N application increased the productivity of maize grains; these effects were more expressive when the crop winter was soybean. With regard to the grain production, the N application strategies were equivalent, inexistent significant differences among them. The N utilization by maize of the crop winter was low, and great part of such nutrient remained in the soil. The greatest Nitrogen Fertilizer Use Efficiency (NFUE) by maize was verified when the total N rate was applied on preplanting (NFUE = 38%). Regardless the N application strategy and the winter crop, the non recovered N (NRN) from the applied urea on the soil-plant system, was on average of 46% (69 kg ha-1 of N) / Orientador: José Eduardo Corá / Coorientador: Takashi Muraoka / Banca: Francisco Maximino Fernandes / Banca: José Carlos Barbosa / Mestre
177

Mitigation of poultry manure pollution in the Fraser Valley

Mpyisi, Edson Rurangwa 05 1900 (has links)
Intensive poultry production in the lower Fraser Valley of British Columbia has resulted in large quantities of poultry manure being spread on limited land space. This manure is spread on land situated above the Abbotsford aquifer. Due to the high amount of nitrogen and phosphorus present in poultry manure, there is a danger of these nutrients leaching into the groundwater of the aquifer as nitrates. High levels of nitrates in drinking water have been linked to various health hazards such as Methemoglobinaemia, stomach cancer, and gastric cancer. The leaching problem is further compounded by the fact that the region has porous soils, a high water table, and very high annual rainfall. This problem was addressed by analyzing several dietary treatments having varying levels of crude protein from a high of 25% CP (crude protein) to a low of 18% CP and supplemented with the commercial amino acids L-LYS , DL-MET , L-THR, and L-TRY . A linear programming model was used to determine the least cost diet from the various dietary treatments. The most efficient dietary treatment was then identified by Manure disposal options such as storage, land application, and transportation were also considered along with their associated costs. Linear programming was used to identify the least cost manure disposal strategy complying with British Columbia environmental regulations by using a combination of the three options. The results from the two models above were then combined to identify the optimum manure management strategy for a poultry farm in the Fraser valley complying with environmental regulations. The results indicate that diets containing lower levels of crude protein and supplemented with amino acids costs less than those containing higher levels of crude protein. These diets perform better because the nitrogen in the protein is utilized more efficiently thereby resulting in less nitrogen excretion in the manure. Manure that contains low amounts of nitrogen costs less to dispose than that having high amounts of nitrogen. Use of diets containing low levels of crude protein and supplementing them with commercial amino acids can lower the costs of poultry farmers significantly while complying with environmental regulations. / Land and Food Systems, Faculty of / Graduate
178

Preventive control of ammonia and odor emissions during the active phase of poultry manure composting

Zhang, Wenxiu 05 1900 (has links)
Traditional measures used in the composting industry for ammonia and odor emissions control are those involving collection and treatment such as thermal oxidation, adsorption, wet scrubbing and biofiltration. However, these methods do not address the source of the odor generation problem. The primary objective of this thesis research was to develop preventive means to minimize ammonia and odor emissions, and maximize nitrogen conservation to increase the agronomic value of compost. Laboratory-scale experiments were performed to examine the effectiveness of various technologies to minimize these emissions during the active phase of composting. These techniques included precipitating ammonium into struvite in composting matrix before it release to outside environment; the use of chemical and biological additives in the form of yeast, zeolite and alum; and the manipulation of key operational parameters during the composting process. The fact that struvite crystals were formed in manure composting media, as verified by both XRD and SEM-EDS analyses, represents novel findings from this study. This technique was able to reduce ammonia emission by 40-84%, while nitrogen content in the finished compost was increased by 37-105%. The application of yeast and zeolite with dosages of 5-10% enhanced the thermal performance of composting and the degree of degradation, and ammonia emission was reduced by up to 50%. Alum was found to be the most effective additive for both ammonia and odor emission control; ammonia emission decreased by 45-90% depending on the dosage, and odor emission assessed via an dynamic dilution olfactometer was reduced by 44% with dosages above 2.5%. This study reaffirmed that aeration is the most influential factor to odor emission. An optimal airflow rate for odor control would be 0.6 L/min.kg dry matter with an intermittent aeration system. Quantitative relationships between odor emission and key operational parameters were determined, which would enable “best management practices” to be devised and implemented for composting. An empirical odor predictive model was developed to provide a simple and direct means for simulation of composting odor emissions. The effects of operating conditions were incorporated into the model with multiplicative algorithm and linearization approximation approach. The model was validated with experimental observations. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
179

Ash from homestead fireplaces and wood as possible sources of minerals for livestock

Ndlovu, Hendry 17 June 2008 (has links)
In this study the mineral composition of ash from fireplaces at rural homesteads was determined to establish if such ash could be a source of minerals to goats. The mineral composition of ash collected from homesteads in six different communal farming regions of South Africa was determined. The ash samples collected in the three northern regions of the country contained between 180 and 248 g Ca/kg dry ash, while those from the Eastern Cape Province contained low concentrations (8–45 g Ca/kg ash) and high concentrations of Si. It is concluded that wood was probably used as fire making material in the northern regions, while cattle manure was probably used in the Eastern Cape regions, though soil contamination could have contributed to the high Si concentrations. The concentration of the Fe and Zn in ash was high while that of the other elements in ash was relatively low and would probably contribute little to a goat’s diet, considering the proportion of ash in a total diet. It is concluded that in some regions of the country goats would be able to ingest a substantial proportion of Ca when scavenging on ash heaps or receiving ash as a dietary supplement, while in other regions this will not be the case. / Dissertation (MInstAgrar (Animal Production))--University of Pretoria, 2008. / Animal and Wildlife Sciences / unrestricted
180

Effects of raw materials on vermicompost qualities

A'ali, Rahman, Jafarpour, Mehrdad, Kazemi, Elahe, Pessarakli, Mohammad 11 January 2017 (has links)
Overuse of the chemical compounds and toxic elements leads to problems and transmission of contaminants and pollutants to humans and other living organisms. One of the industries’ byproducts of the agriculture sector is production of various composts from the organic raw materials that the best type of which is so – called Vermicompost. In this study, effects of raw materials on qualitative and quantitative characteristics of Vermicompost are discussed. To do so, sheep manure, pomegranate peels, spent mushroom compost either singly or double, triple or fourfold chopped corn, sugar beet pulp and sawdust were used. This research project was conducted in a completely randomized design experiment with 23 treatments with 3 replications. Results revealed that various bed combinations exert different effects on Vermicompost quality such that, the Vermicomposting process led to a significant decrease in electrical conductivity (EC) and a significant increase in pH in most of the culture (seed) beds. Also, the levels of Nitrogen, Phosphorous and Potassium in most treatments increased following completion of the vermicomposting process. As a result, this process can be introduced as an organic fertilizer with complete nutrients for improving chemical characteristics of agricultural wastes to usable fertilizers.

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