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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.
71

Resíduos da indústria sucroenergética como componentes de substratos para produção de mudas pré-brotadas de cana-de-açúcar /

Lima, Felipe Biondi Fernandes de. January 2016 (has links)
Orientador: José Eduardo Corá / Banca: Carolina Fernandes / Banca: Adolfo Valente Marcelo / Resumo: A utilização de resíduos da indústria sucroenergética como substrato para a formação de mudas pré-brotadas torna o processo de produção cana-de-açúcar sustentável, sendo os próprios resíduos utilizados para uma nova geração da cultura. O presente trabalho teve como objetivo obter um substrato, composto por resíduos da indústria sucroenergética, adequado para a produção de mudas pré-brotadas de cana-de-açúcar. Os tratamentos foram constituídos pela combinação de três substratos isolados: torta de filtro, cinza e bagaço de cana-de-açúcar, os quais foram comparados a um substrato testemunha. Os tratamentos foram homogeneizados seguindo a proporção volume:volume e destas misturas foram realizadas as caracterizações físicas e químicas. Realizou-se o plantio dos minirrebolos em tubetes de 180 cm³, respeitando a densidade de cada material, e, então, os materiais foram levados para casa de vegetação por 90 dias. As mudas foram avaliadas quanto ao desenvolvimento da parte aérea, radicular, porcentagem de brotação e análise químicas das folhas. O delineamento experimental utilizado foi inteiramente casualizado, com dezoito repetições. Foi realizada a análise de variância e, quando significativa, as médias foram comparadas pelo teste de Scott-Knott, a 5% de probabilidade; foi realizado análise de correlação entre todos os resultados. As mudas cultivadas no substrato T2/10-C2/10-B6/10 apresentaram maior desenvolvimento da parte aérea e radicular, maior facilidade para retirada do tubete,... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of waste of sugarcane industry as substrate for the formation of pre-sprouted seedlings makes the process of sugarcane sustainable production, the waste itself used for a new generation of culture. This study aimed to obtain a substrate, composed of waste from sugarcane industry, suitable for the production of pre-sprouted of sugarcane seedlings. The treatments were a combination of three insulated substrates: filter cake, ash and bagasse sugarcane, which were compared to a control substrate. The treatments were homogenized following the ratio volume: volume mixtures of these and the physical and chemical characterizations were carried out. There was the planting of "minirrebolos" in tubes of 180 cm³, respecting the density of each material, and then the materials were taken to a greenhouse for 90 days. The seedlings were evaluated for the development of shoot, root, sprouting percentage and chemical analysis of the leaves. The experimental design was completely randomized, with eighteen repetitions. Analysis of variance was performed and, when significant, the means were compared by the Scott-Knott test at 5% probability; correlation analysis was performed between all results. Seedlings grown in substrate T2/10-C2/10-B6/10 presented further development of root and shoot, easier to remove the cartridge, lower density and higher amount of nutrients / Mestre
72

Viabilidade econômica da compostagem do lodo de esgoto para uso agrícola /

Visentin, Roseli. January 2019 (has links)
Orientador: Maura Seiko Tsutsui Esperancini / Coorientador: Caroline de Moura D'Andrea Mateus / Banca: Rosemary Marques de Almeida Bertani / Banca: Nuria Rosa Gagliardi Quintana / Resumo: O uso do lodo de esgoto, um dos resíduos de efluentes do tratamento de esgoto, tem sido tema amplamente abordado sob os aspectos ambiental, legal e econômico. Isto se deve à sua crescente produção, consequência do aumento do serviço de saneamento básico e complexidade da composição do lodo de esgoto, rico em nitrogênio, porém com carga patogênica que deve ser eliminada por processo economicamente viável, permitindo seu uso à luz da legislação vigente. Um dos usos deste resíduo é o agrícola, que pelo processo de compostagem, quando associado com material estruturante, rico em carbono, propicia a eliminação de patógenos e homogeneização da mistura que recebe a denominação de fertilizante orgânico composto classe D, podendo, então, ser aplicado no solo e em culturas predeterminadas pelo Ministério da Agricultura, Pecuária e Abastecimento. O objetivo deste trabalho foi avaliar a viabilidade econômica da compostagem do lodo de esgoto produzido na Estação de Tratamento de Esgoto (ETE), localizada na Fazenda Experimental Lageado, no município de Botucatu, misturado com duas fontes de carbono: bagaço de cana-de-açúcar ou casca de eucalipto. A mistura permaneceu em estufa por dois meses, período em que foi revolvida por máquina compostadora, de acordo com parâmetros avaliados periodicamente, tais como a temperatura e umidade. A análise econômica deste projeto foi realizada com acompanhamento do processo, coleta de dados e elaboração de fluxos de caixa representados pela diferença entr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of sewage sludge, a waste of the sewage treatment effluents, has been the subject widely discussed under environmental, legal and economic aspects. This is due to increasing to its production, as a result of the increase of the basic sanitation service, complexity of the composition of sewage sludge, rich in nitrogen, but with pathogenic load which must be eliminated by an economically viable process, allowing its use in light of the legislation in force. One of the uses of this residue is agriculture, which by the process of composting, when associated with structural material, rich in carbon, promotes the elimination of pathogens and homogenization of the mixture that receives the title of organic compound fertilizer class D, which may then be applied in the soil and in predetermined cultures by the Ministry of Agriculture, Livestock and Supply. The objective of this work was to evaluate the economic viability of composting of sewage sludge produced at Sewage Treatment Station (STS) located at the Experimental Farm Lageado, in the city of Botucatu, mixed with two carbon sources: sugarcane bagasse and eucalyptus bark. The mixture remained in the greenhouse for two months, during which time it was stirred by composter machine, according to periodically evaluated parameters, such as temperature, humidity. The economic analysis of this project was accomplished with the process monitoring, data collection and preparation of cash flows represented by the difference between the investment in plant and equipment, composting operation costs and revenues from marketing of organic fertilizer and the cost savings with transport and disposal of sewage sludge in landfill. The indicators Net present value (NPV), Internal rate of return (IRR), Discounted payback period (DPP) and Benefit- cost ratio (BCR) were calculated for six scenarios: a combination of two types of structural material and three ... / Mestre
73

Carbono orgânico e atributos físicos do solo após a aplicação de esterco bovino /

Magalhães, Ludmila. January 2017 (has links)
Orientador: Carolina Fernandes / Banca: José Eduardo Corá / Banca: Adolfo Valente Marcelo / Resumo: O esterco bovino contém elevados teores de matéria orgânica, que pode elevar os teores de carbono orgânico no solo e proporcionar melhorias nos atributos físicos do solo. Isso ocorre devido o carbono orgânico ser um agente cimentante das partículas minerais do solo. Objetivou-se com esse trabalho avaliar o efeito da adubação orgânica (esterco bovino) nos atributos do solo: carbono orgânico, carbono orgânico particulado, carbono orgânico associado aos minerais, distribuição de agregados do solo por classes de tamanho, índice de estabilidade de agregados do solo, condutividade hidráulica do solo saturado, macroporosidade, microporosidade, porosidade total, resistência do solo à penetração e densidade do solo. O experimento foi realizado na Fazenda de Ensino, Pesquisa e Extensão da UNESP, Câmpus de Jaboticabal, em um Latossolo Vermelho eutroférrico, de textura argilosa. O delineamento experimental foi em blocos casualizados, constando de cinco doses de esterco bovino (0, 15, 30, 45 e 60 Mg ha-1) com quatro repetições. Foram coletadas amostras de solo indeformadas, na camada de 0-0,10 m, para a determinação da condutividade hidráulica do solo saturado (K0), macroporosidade (Ma), microporosidade (Mi), porosidade total (PT), resistência do solo à penetração (RP) e densidade do solo (Ds). Na mesma camada, foram coletadas amostras de solo deformadas para a determinação da distribuição de agregados do solo por classes de tamanho, índice de estabilidade de agregados do solo (IEA), carb... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cattle manure contains high levels of organic matter, wich can increase the organic carbon content in the soil and provide improvements in the physical attributes of this. This occurs because the organic carbon it is a cementing agent for the soil mineral particles. From this, the objective of this paper was to evaluate the effect of organic fertilization (cattle manure) on the soil attributes: organic carbon, particulate organic carbon, organic carbon associated to minerals, soil aggregates distribution by sizes classes, soil aggregates stability index, saturated soil hydraulic conductivity, macroporosity, microporosity, total porosity, soil resistance to penetration, and soil bulk density. The experiment was carried out at the Teaching, Research and Extension Farm of UNESP, Jaboticabal Campus, in a clayey Oxisol. The experimental design was a randomized complete block, consisting of five rates of cattle manure (0, 15, 30, 45 e 60 Mg ha-1), with four replications. Undisturbed soil cores were collected at the 0-0.10 m deep layer to determine the hydraulic conductivity of saturated soil (K0), macroporosity (Ma), microporosity (Mi), total porosity (PT), soil resistance to penetration (RP) and soil bulk density (Ds). At the same layer, deformed soil cores were collected to determine the soil aggregates distribution by sizes classes, aggregate stability index of soil (IEA), organic carbon (CO), and physical fractionation of organic carbon, in with was determined the particulate organic carbon (COP). The organic carbon associated to minerals (COAM) was obtained by difference between CO and COP. An Analysis of Variance was performed to polynomial regression, to the evaluated soil attributes in function of cattle manure rates, using the F test with 5% probability. The values of CO, COP, IEA, PT, Ma, RP, Ds and K0 were influenced by the ... (Complete abstract click electronic access below) / Mestre
74

Growth, development and yield responses of sorghum to water deficit stress, nitrogen fertilizer, organic fertilizer, and planting density

Bayu, Wondimu 20 September 2006 (has links)
Please read the abstract in the 00front part of this document Copyright 2004, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bayu, W 2004, Growth, development and yield responses of sorghum to water deficit stress, nitrogen fertilizer, organic fertilizer, and planting density, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-09202006-093510 / > / Thesis (PhD (Agronomy))--University of Pretoria, 2004. / Plant Production and Soil Science / unrestricted
75

Organic manure effects on selected soil properties, water use efficiency and grain yield of sunflower

Mokgolo, Matome Josphinos January 2016 (has links)
MSCAGR (Soil Science) / Department of Soil Science / The application of organic manures as alternatives to reduce the use of mineral fertilizers is considered a good agricultural practice for smallholder farmers. However, the effect of organic manure on soil properties and crop yield depends upon its application rate and chemical composition. Climatic seasonal variability within the study area could adversely affect crop production. The amount of rainfall and temperature are among the most important factors that determines crop production. This field experiment was carried out during the 2013/2014 and 2014/2015 cropping seasons at the University of Venda experimental farm which is located about 2 km west of Thohoyandou town in the Vhembe District, Limpopo Province. The main objective of this study was to determine the effect of three types of organic manure (cattle, poultry and their combination (1:1)) on yield and water use efficiency of sunflower (Helianthus annuus L.) and selected soil physical and chemical properties under rainfed conditions. The experiment was a randomized complete block design (RCBD) with four treatments and four replications (control (C0), cattle manure (CM), poultry manure (PM) and their combination (CM + PM)). All organic manures were applied 21 days before planting at a rate equivalent to 20 t ha-1. The manures were incorporated in the soil using a hoe to an approximate depth of 10 cm. Crop water use (WU) and water use efficiency (WUE) were determined using the water balance equation. Rainfall was measured using three standard rain gauges installed on the experimental site. Change in soil moisture storage was determined by monitoring soil moisture content weekly using a neutron water meter (NWM), calibrated on the experimental site. Data on sunflower dry matter and leaf area index (LAI) was collected at flower bud stage, flowering stage and at grain maturity stage. Plant height and stem girth were also determined at the same developmental stages. Grain yield was measured at physiological maturity. xv Analysis of variance (ANOVA) was carried out using SPSS software. Due to seasonal variability encountered during the two cropping seasons, particularly in terms of rainfall, further analysis of two factors (viz. cropping season and organic manure) and their interaction were performed. The differences between treatment means were separated using the least significant differences (LSD) procedure. The results showed that organic manure application had no significant effect on soil physical properties. Poultry manure application resulted in lowest bulk density (BD) with a decrease of 32% in the top layer (0 – 20 cm) compared to control. Cattle manure + PM and CM application decreased BD in the top layer by 14% and 9% compared to control, respectively. Poultry manure and CM recorded almost the highest similar stable aggregate fractions at all soil depths. Poultry manure recorded the highest final infiltration rate and cumulative infiltration followed by CM and CM + PM. The control treatment retained the highest mean water content compared to other treatments at both field capacity (FC) and wilting point (WP). Cattle manure + PM and PM recorded the least mean water content among others at FC and WP respectively. This could be as a result of increased micropores by organic manure application on a clayey soil which allowed an ease movement of water that control treatment which had no manure application. Total N, Ca, and Zn were significantly different between treatments in the first cropping season while K, Na, CEC and Zn were significantly different in second cropping season. pH recorded no significant difference in all treatments in both cropping seasons. CM + PM recorded the highest OC at top layer (0 – 20 cm) in both cropping seasons compared to other treatments. Dry matter yield and LAI at flower bud, flowering and maturity stages increased with the application of different manures compared to the C0. Organic manure application showed a significant (p<0.05) effect on dry matter at all growth stages in the second cropping season. Organic manure had a significant effect on LAI only at flower bud stage of the first cropping season, with PM and CM + PM recording the highest similar value of 1.31. The manure xvi application also showed a significant (P<0.05) effect on plant height and stem girth at all growing stages in the second cropping season, whereas in the first cropping season the significant effect was only in the flower bud stage for both parameters. Grain yield was significantly affected by the manure application in the second cropping season. Manure application in the second cropping season resulted in an increase in the grain yield compared to the first cropping season, except for PM where the grain yield decreased significantly by 167.92% from the first cropping season. Then high grain yield in the second cropping season could be as a result of high WUE reported. The manure application had a significant effect (p<0.05) on water use efficiency (WUE) in the second cropping season. The WUE recorded the highest values under CM and CM + PM treatments in second cropping season than in first cropping season, while PM recorded the highest WUE value in the first cropping season. Generally, organic manures used obtained higher grain yield and WUE compared to control. Keywords: Organic manure, smallholder farmers, sunflower and water use efficiency
76

Sanjeevak as a source of nutrients and phytohormones for production and propagation of plants

Orendo-Smith, Richard 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The use of cowdung as an organic fertilizer in Asian and African agriculture is an ancient practice. This explains its renewed interest, partly due to the financial inability of most farmers to purchase agrochemicals but also the ever increasing need to adopt greener technologies that do not adversely affect soil health, water quality, biodiversity and promote sustained or even increased food production. In this context, many innovative farmers have developed their own novel technologies based on the use of local resources. One such innovation is Sanjeevak (a mix of cow dung, cow urine, water and a handful of sugar); which showed very promising boosting effect on crop productivity. However, very little scientific work has so far been conducted to evaluate its effect as an organic product for soil amendments. The present study was subdivided into three main objectives. (i) To assess the fertilizing value, human health and ecological risk profiles of Sanjeevak; (ii) To screen Sanjeevak for phytohormones content using Salkowski colorimetric method and liquid chromatography – mass spectrometry (LC-MS) (iii) To evaluate Sanjeevak application at various rates on growth parameters and yield of various crops cultivated in glasshouse and field conditions. Sanjeevak was assessed for its micro and macro nutrients contents. The analysis showed the presence of micronutrients such as Mg, Na, Ca and Zn at variable concentrations and phosphorus (P) (0.007%) and potassium (K) (0.063%). However, Sanjeevak content in total nitrogen (TN) (0.11%), and total organic carbon (TOC) (0.71%) was very low; suggesting that it may be a viable source of nutrients only if applied at higher and consistent rates or alternatively by improving its formulation. Also, Sanjeevak was analysed for its microbiological characteristics and level of heavy metals content in comparison to the strictest legislations that regulate the use and application of wastewater sludge to agricultural land in South Africa. The findings showed that heavy metals, which averaged from 0.03±0.01 for Arsenic (As) to 4.74±0.92 mg/kg for Zinc (Zn) and feacal coliform was estimated at 1.2×102 CFU/g dry matter measured were considerably below the threshold (for Arsenic between 40 to 75 mg/kg dry weight; for Zinc between 2800 to 7500 mg/kg dry weight) and faecal coliform bacteria between 1000 to 1×107 CFU/g dry weight for application as a source of soil amendments. Studies investigating the detection and concentration of phytohormones in Sanjeevak were carried out. In using the Salkowski colorimetric method to detect and quantify auxins from Sanjeevak and its composites (cow urine and dung), the results showed the presence of indole-3-acetic acid (IAA) at variable concentrations ranging from 20.38±2.1 ppm in cow urine, 20.1±6.6 ppm in cow dung, Sanjeevak 17.90±1.1 ppm to up to 138.31±12.6 ppm when LTRP was added to Sanjeevak bacterial cultures and by varying parameters such as incubaton time and temperature. Screening of the above mentioned samples for IAA using LC-MS analysis validated earlier findings. Further analysis of these results strongly emphasized the influence of bacteria in Sanjeevak in producing IAA. Trials were carried out both in the glasshouse and the field. In the greenhouse, different Sanjeevak application rates consistently confirmed its root promoting effect on crops such as tomato, cucumber and grapevine and increased wheat yield independent of the nutrients it contains. Marginal increases were recorded between treatments under field conditions; for example compost and compost + Sanjeevak 20.35 and 20.61 t/ha; and 2.46 and 2.60 t/ha compared to the control 11.67 t/ha and 1.29 t/ha respectively for tomato and maize. However, statistical analysis of the results obtained, revealed that there was no difference between treatments (control, compost, Sanjeevak and compost + Sanjeevak) for the same crop tested due to the high coefficient of variation of the data. Therefore, the use of Sanjeevak as an organic source of soil amendments may be considered as a cheaper alternative to effective microorganisms (EM) technology made up of local and natural resources. As observed in the study, it may be best used in combination with a reliable source of plant nutrients. / RESUMEE: L'utilisation des excréments de vaches comme engrais organique dans l'agriculture asiatique et africaine est une pratique très ancienne. Ceci explique son intérêt renouvelé, en partie due à aux restrictions monétaires de la plupart des agriculteurs d'acheter des produits agrochimiques, mais aussi la nécessité croissante d'adopter des technologies vertes qui ne nuissent pas à la qualité des sols, des eaux, la biodiversité et qui permettent d’améliorer la production agricole. C’est dans ce contexte que de nombreux paysans ont développé des techniques nouvelles dépendant des ressources naturelles et locales. L’utilisation de Sanjeevak (un mélange d’excréments de vaches, d’urine de vaches, l'eau et du sucre), a démontré sa capacité à accroître la productivité des plantes vivrières. Cependant, très peu de travaux scientifiques ont jusqu'à présent été menée pour étudier ce produit organique. La présente étude a été subdivisée en trois objectifs principaux. (i) Evaluation de la valeur fertilisante, et les profils de risques écologiques et sanitaires de Sanjeevak, (ii) Etudes de détection des phytohormones et leurs concentrations en utilisant une méthode colorimétrique adaptée de celle de Salkowski et la chromatographie liquide - spectrométrie de masse (LC-MS) (iii) Etude des effets de l’utilisation de Sanjeevak a différents taux d’applications sur la croissance et le développement des plants. Sanjeevak a été évaluée pour son contenu en micro et macro nutriments. L'analyse a montré la présence d'oligo-éléments tels que Mg, Na, Ca et Zn à des concentrations variables. De plus, son contenu en éléments majors tels que le phosphore (P) (0.007%), le potassium (K) (0.063%), l’azote (N) (0.11%), et carbone (C) (0.71%) est très faible; suggérant qu'il pourrait être une source viable de nutriments que si elle est appliquée à des taux plus élevés et répétés ou alternativement en améliorant sa formulation. En outre, Sanjeevak a été analysé pour ses caractéristiques microbiologiques et sa concentration en métaux lourds en comparaison a la législation qui réglemente l'utilisation et l'application de déchets liquide d’origines domestiques sur les terres agricoles en Afrique du Sud. Les résultats ont révélé que des métaux lourds et le niveau de coliformes fécaux mesuré était inférieur aux seuils d'application en tant que source d'amendements de sols agricoles. Les études portant sur la détection et la concentration d’hormones végétales ont été effectuées. En utilisant la méthode colorimétrique de Salkowski pour détecter et quantifier les auxines de Sanjeevak, les urines et les excréments de vaches; les résultats ont révélé la présence d'acide indole-3-acétique (AIA) à des concentrations variables dans les urines, les excréments et Sanjeevak. Une autre analyse des échantillons mentionnés ci-dessus pour les AIA en utilisant LC-MS a validé les résultats obtenus au préalable. L’étude détaillée de ces résultats confirme l'influence des micro-organismes dans la production des hormones végétales. Concernant les expériences sous serre, les différents taux d'application de Sanjeevak ont confirmé son effet stimulant à la croissance accélérée des racines des plantes telles que la tomate et les raisins et augmenté le rendement du blé indépendamment des nutriments qu'il contient. L'analyse statistique des résultats obtenus dans des conditions de terrain, a révélé qu'il n'y avait pas de différence entre les traitements (contrôle, compost, compost + Sanjeevak et Sanjeevak) pour la même plantes testées. Par conséquent, l'utilisation de Sanjeevak comme un produit organique qui améliore la qualité des sols et le rendement des cultures vivrières; peu être considéré comme un inoculum contenant des microorganismes constitué de ressources locales et naturelles. Comme l'a observé dans l'étude, il pourrait être mieux utilisé en combinaison avec une source fiable de nutriments végétaux. / AFRIKAANSE OPSOMMING: Die gebruik van beesmis as 'n organiese kunsmis in Asië en Afrika is' n eeu-oue landbou praktyk. Dit verklaar die hernude belangstelling, deels vanweë die finansiële onvermoë van meeste boere om landbouchemikalieë aan te koop, maar ook as gevolg van die toenemende behoefte vir groener tegnologie wat nie nadelig is vir grond gesondheid, waterkwaliteit, biodiversiteit en wat volhoubaarheid of selfs verhoogde voedselproduksie bevorder. In hierdie konteks het baie vindingryke boere hul eie nuwe tegnologie, gebaseer op die gebruik van plaaslik verkrygde hulpbronne, ontwikkel. `n Voorbeeld hiervan is Sanjeevak ('n mengsel van beesmis, beesurine, water en die handvol melasse), wat belowende bevorderende effekte op gewas produktiwiteit en grond mikroflora getoon het. Tot dusver was daar egter baie min wetenskaplike werk gedoen om die effek daarvan as 'n organiese produkte vir grond wysigings te evalueer. Hierdie studie was verdeel in vier belangrike doelwitte. (i) Om die bemestingswaarde, menslike gesondheid en ekologiese risiko-profiele van Sanjeevak te evalueer; (ii) Om Sanjeevak vir fitohormone inhoud en vlakke met behulp van 'n kolorimetriese metode afgelei van dié van Salkowski en vloeistofchromatografie – massaspektrometrie (LC-MS) te besigtig; (iii) Glashuis en veld waarneming reaksies met betrekking tot groei parameters en opbrengs van verskeie gewasse na die toediening van Sanjeevak by verskillende tempos; (iv) Laastens, om die effek van die Sanjeevak voorbehandeling op saad ontkieming en voortplanting te toets in vergelyking met die metodes en tegnieke wat gereeld gebruik word. Sanjeevak is geassesseer vir die mikro-en makro voedingstowwe inhoud. Die analise het die teenwoordigheid van mikrovoedingstowwe soos Mg, Na, Ca en Zn by wisselende konsentrasies, asook fosfor (P) (0.007%) en kalium (K) (0.063%), getoon. Sanjeevak inhoud van totale stikstof (TN) (0.11%), en die totale organiese koolstof (TOC) (0.71%) was egter baie laag, wat daarop dui dat dit slegs 'n lewensvatbare bron van voedingstowwe is indien dit by hoër en konsekwente tempos toegedien word of alternatiewelik wanneer formulering daarvan verbeter word. Sanjeevak was ook ontleed vir die mikrobiologiese eienskappe en die vlakke van swaar metale in vergelyking met die streng wetgewing wat die gebruik en toediening van afvalwater slyk op landbougrond in Suid-Afrika reguleer. Die bevindinge het getoon dat swaar metale en fekalieë kolivorm vlakke hier gemeet, aan die drumpel vereistes voldoen vir die toediening as ‘n grondverbeteringsmiddel. Studies wat die opsporing en die konsentrasie van fitohormone in Sanjeevak ondersoek is uitgevoer. In die gebruik van die Salkowski kolorimetrise metode om die ouksiene op te spoor en te kwantifiseer uit Sanjeevak en sy mengsel (beesurine en mis), het die resultate die teenwoordigheid van indol-3-asynsuur (IAA) by wisselende konsentrasies wat wissel van 20 tot 140 ppm in beesurine, beesmis en Sanjeevak getoon. Evaluering van die bogenoemde monsters vir IAA met behulp van LC-MSanalise bevestig vroeër bevindings. Verdere ontleding van hierdie resultate beklemtoon sterk die invloed van Sanjeevak mikrobiota in fitohormone produksie. Proewe is uitgevoer in die glashuis en die veld. In die glashuis eksperimente, is het die verskeie toedieningstempo van Sanjeevak herhalend die wortelbevorderende effekte bevestig op gewasse soos tamaties, komkommer en wingerdstok en dit het opbrengs van koring verhoog, onafhanklik van die voedingstowwe wat dit bevat. Statistiese analise van die resultate verkry onder veldtoestande, het getoon dat daar geen verskil tussen die behandelings (kontrole, kompos, Sanjeevak en kompos + Sanjeevak) was nie, gegee dat dieselfde gewas getoets was. Ten slotte, laboratorium-eksperimente op Sanjeevak as voor-behandeling om die beworteling te verbeter van die wingerdstok (Ramsey) onderstok steggies, het baie belowende resultate getoon in vergelyking met naftaleen asynsuur (NAA) voorbehandeling en die kontrole. Dit beklemtoon die feit dat Sanjeevak 'n alternatief kan wees en wat verdere studie verdien, hoofsaaklik as gevolg van sy lae-koste en omgewingsvriendelike prosedures. Die gebruik van Sanjeevak as 'n organiese grondverbeteringsmiddel vir gewasproduksie en voortplanting kan beskou word as' n goedkoper alternatief tot effektiewe mikro-organisme (EM) tegnologie wat uit plaaslike en natuurlike hulpbronne saamgestel is. Soos waargeneem in die studie, kan dit die beste gebruik word in kombinasie met 'n betroubare bron van plantvoedingstowwe. Dus, moet die gebruik daarvan vir die produksie van gewasse en voortplanting aangemoedig word.
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Qualidade de solo em pomar de mangueiras "tommy atkins" adubadas com fontes orgânicas no semiárido paraibano. / Soil quality in orchard of mango plant ‘Tommy atkins’ fertilized with organic sources in semiarid Paraiba.

SILVA, Semirames do Nascimento. 01 June 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-06-01T13:47:37Z No. of bitstreams: 1 SAMIRES DO NASCIMENTO SILVA - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 973646 bytes, checksum: 270edb29910dc87c2a25e82051b0f47a (MD5) / Made available in DSpace on 2018-06-01T13:47:37Z (GMT). No. of bitstreams: 1 SAMIRES DO NASCIMENTO SILVA - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 973646 bytes, checksum: 270edb29910dc87c2a25e82051b0f47a (MD5) Previous issue date: 2014-09 / A preocupação com a qualidade do solo tem crescido à medida que seu uso e mobilização intensiva passaram a resultar em diminuição da sua capacidade produtiva e sustentável ao longo dos anos. Objetivou-se com o trabalho avaliar a qualidade de solo em pomar de mangueiras (Mangífera indica L.) var. Tommy atkins adubadas com fontes orgânicas no semiárido paraibano, por meio dos atributos químicos, físicos e biológicos do solo. O experimento foi conduzido no Setor de Fruticultura do IFPB Campus Sousa, em delineamento inteiramente casualizado, com oito tratamentos e três repetições, totalizando 24 unidades experimentais. Realizou-se a coleta de solo, em outubro de 2013, na profundidade 0-20 cm, em cada unidade experimental. Para os atributos químicos foram avaliados: o pH em água, a condutividade elétrica no extrato 1:5; os teores de Ca+2, Mg+2, Na+, K+ trocáveis e P assimilável e os teores de carbono total e estimou-se os valores de: saturação por base e percentagem de sódio trocável. Com os teores de carbono total, obtiveram-se os teores de matéria orgânica. Quanto aos atributos físicos avaliou-se: os teores de areia, silte e argila, o grau de floculação, densidade de partículas, densidade do solo e a porosidade total. Os atributos biológicos avaliados foram: ocorrência e densidade de microrganismos, respiração edáfica, C da biomassa e quociente metabólico. Não foram encontradas diferenças significativas estatisticamente para os atributos químicos e físicos indicadores da qualidade do solo. Os maiores valores observados para o quociente metabólico foram para o esterco de aves e para o composto orgânico. A análise de componentes principais possibilitou a visualização conjunta dos atributos químicos, físicos e biológicos, verificando como os atributos foram afetados pela presença ou ausência de fontes orgânicas. / Concern for soil quality has grown as its use and intensive mobilization began to result in a decrease of its productive capacity and sustainable over the years. The objective of the study was to evaluate the quality of soil in an orchard of mango (Mangifera indica L.) var. Tommy atkins fertilized with organic sources in semiarid Paraiba, through chemical, physical and biological soil properties. The experiment was conducted at the Department of Fruit Crops IFPB Campus Sousa, in a completely randomized design with eight treatments and three replications, totaling 24 experimental units. Held the soil collected in October 2013 at 0-20 cm depth in each experimental unit. For chemical attributes were evaluated: pH, electrical conductivity extract 1: 5; the Ca2+, Mg2+, Na+, K+ and exchangeable P assimilable and the contents of total carbon and estimated the values of: base saturation and exchangeable sodium percentage. With the levels of total carbon, obtained the contents of organic matter. As for physical attributes is evaluated: the proportions of sand, silt and clay, the degree of flocculation, particle density, bulk density and total porosity. The biological attributes evaluated were: occurrence and density of microorganisms, soil respiration, biomass C and metabolic quotient. No statistically significant differences were found for physical and chemical indicators of soil quality attributes. The highest values were observed for the metabolic quotient were for poultry manure and organic compost. The principal component analysis allowed the joint visualization of chemical, physical and biological attributes, checking how the attributes were affected by the presence or absence of organic sources.
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Fertilizantes de leguminosas: tecnologia inovadora de aduba??o verde para provis?o de nitrog?nio em sistemas org?nicos de produ??o. / Legume fertilizers: innovative technology of green manuring for nitrogen supply in organic farming systems.

Almeida, Maxwell Mer?on Tezolin Barros 16 March 2007 (has links)
Made available in DSpace on 2016-04-28T14:58:33Z (GMT). No. of bitstreams: 1 2007- Maxwell Mercon Tezolin Barros Almeida.pdf: 1302858 bytes, checksum: 1bdf7888e20d418ce73170bea64d112e (MD5) Previous issue date: 2007-03-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / One of the main limitations to the organic food production is the reduced availability of low cost and efficient nitrogen (N) sources. Green manuring practices, in rotation or intercropped, have been used, but hardly are they able to supply crop needs. This dissertation presents an innovative technology of green manuring, derived of the cutting, dehydration and milling of the aerial biomass of some plants from Leguminosae family (with high potential of biological N2 fixation, N accumulation and handling easiness), with posterior storage and use of the produced material, called legume fertilizer. The technology allows the green manure storage, the production systematization and its use in more appropriate amounts and times, favoring the synchronization/efficiency of N provision. The objects of this study were: the development and evaluation of different production forms of legume fertilizers three herbaceous species: velvet bean (Mucuna pruriens), sunn hemp (Crotalaria juncea) and arachis (Arachis pintoi), and two species of tree: gliricidia (Gliricidia sepium) and leucaena (Leucaena leucocephala) ; the physical and chemical characterization of these materials, the utilization potential as alternative sources of N for organic farming systems, their influence on the shelf life of lettuce (Lactuca sativa cv. Vera), on chemical and biological soil attributes and on germination and establishment of arugula (Eruca sativa cv. Cultivada) seedlings. Three experiments have been conducted: one in field with lettuce, and two in green house with arugula. Legume fertilizers were compared at N basis with poultry bed manure from meat industry. The gliricidia fertilizer showed better physical and chemical attributes (lower C/N and lignin/N ratios) implying higher potential for biodisponibilization of N. This potential was corroborated for two experiments, in which the concentration and accumulation of N in the aerial part of lettuce and arugula was significantly superior to the other organic sources of N (velvet bean fertilizer and poultry bed manure). However, in the other experiment of arugula, the efficiency of five legume fertilizers and poultry bed manure were similar. The incorporation and the reduction of the applied doses of N had increased the efficiency of the provision of N for arugula. Antagonistic effect had been only observed on the germination and establishment of arugula seedlings when the legume fertilizers had been incorporated in the soil, but not when applied in surface. Lettuce shelf life was not affected by application of these organic sources of used N. The legume fertilizers and the poultry bed manure had favored the accumulation of C and total N, and the soil microbial activity with similar magnitudes. This dissertation indicates that legume fertilizers are promising sources of N for the organic farming systems, capable to replace the factory poultry bed manure at the same N level. This potential assumes relevance since poultry bed manure, one of the most used and efficient sources of organic of N, has some restrictions for its use in organic agriculture. / Um dos principais entraves ? produ??o org?nica de alimentos ? a reduzida disponibilidade de fontes de nitrog?nio (N) eficientes e de baixo custo. Pr?ticas de aduba??o verde, em rota??o ou cons?rcio, t?m sido utilizadas, mas dificilmente conseguem garantir as exig?ncias das culturas. Esta disserta??o apresenta uma tecnologia inovadora de aduba??o verde, derivada do corte, desidrata??o e moagem da biomassa a?rea de determinadas plantas da fam?lia Leguminosae (com elevado potencial de fixa??o biol?gica de N2, ac?mulo de N e facilidade de manejo), com posterior armazenagem e uso do material produzido, denominado fertilizante de leguminosa. A tecnologia permite a estocagem do adubo verde, a sistematiza??o da produ??o e seu uso em quantidades e ?pocas mais adequadas, favorecendo a sincronia/efici?ncia da provis?o de N. Foram objetos deste estudo: o desenvolvimento e a avalia??o de diferentes formas de produ??o de fertilizantes de leguminosas tr?s de esp?cies herb?ceas: mucuna cinza (Mucuna pruriens), crotal?ria (Crotalaria juncea) e arachis (Arachis pintoi), e dois de esp?cies arb?reas: gliric?dia (Gliricidia sepium) e leucena (Leucaena leucocephala) ; a caracteriza??o f?sica e qu?mica desses materiais, o potencial de uso como fontes alternativas de N para sistemas org?nicos de produ??o, a influ?ncia das aduba??es sobre a vida ?til p?s-colheita de alface (Lactuca sativa cv. Vera), sobre atributos qu?micos e biol?gicos do solo e sobre a germina??o e estabelecimento de pl?ntulas de r?cula (Eruca sativa cv. Cultivada). Tr?s experimentos foram conduzidos: um em campo com a cultura da alface, e dois em vasos com r?cula. Em todos eles, as aduba??es com os fertilizantes de leguminosas foram comparadas com cama de avi?rio industrial, proveniente de galp?o de frangos para abate, assegurando-se doses equivalentes de N-total. O fertilizante de gliric?dia foi o que apresentou maior potencial f?sico e qu?mico para biodisponibiliza??o de N (rela??es C/N e lignina/N, baixas). Esse potencial foi corroborado por dois experimentos, nos quais a concentra??o e ac?mulo de N na parte a?rea de alface e r?cula foram significativamente superiores aos proporcionados pelas demais fontes org?nicas de N (fertilizante de mucuna cinza e cama de avi?rio). No entanto, no outro experimento de r?cula, a efici?ncia dos cinco fertilizantes de leguminosas e da cama de avi?rio foi semelhante. A incorpora??o e a diminui??o das doses de N aplicadas aumentaram a efici?ncia da provis?o de N para a r?cula. Efeitos antag?nicos, s? foram observados sobre a germina??o e estabelecimento das pl?ntulas de r?cula quando os fertilizantes de leguminosas foram incorporados ao solo, mas n?o quando aplicados em cobertura. A vida ?til p?s-colheita das alfaces n?o foi influenciada quanto ? fonte org?nica de N utilizada. Os fertilizantes de leguminosas e a cama de avi?rio favoreceram ao ac?mulo de C e N-total, e a atividade microbiana no solo com magnitudes semelhantes. Esta disserta??o indica que os fertilizantes de leguminosas s?o fontes promissoras de N para os sistemas org?nicos de produ??o, capazes de substituir a cama de avi?rio industrial, em dosagem equivalente de N-total. Esse potencial assume relev?ncia, tendo em vista que a cama de avi?rio, uma das fontes de org?nicas de N mais usadas e eficazes, sofre restri??es quanto ao seu emprego em agricultura org?nica.
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Biomass production and nitrogen transformations in a hybrid poplar plantation

Lteif, Arlette. January 2007 (has links)
Hybrid poplars are fast-growing trees, well-suited for the production of bioenergy and wood products. They are often planted on marginal agricultural lands where soil fertility is low. The application of nitrogen (N) fertilizers is expected to replenish soil N reserves and support hybrid poplar productivity throughout the short-rotation growth period. The objective of this thesis was to assess the effect of two organic N fertilizers, papermill biosolids and pig slurry, on tree growth, nutrient uptake and soil fertility in a Populus trichocarpa x Populus deltoides hybrid poplar plantation. I also evaluated how these organic amendments influenced N transformation rates and denitrification losses. Hybrid poplar growth was greater when trees were fertilized with mixed biosolids: pig slurry fertilizer treatments compared to biosolids or pig slurry alone. Assessment of foliar nutrition with the critical value approach (CVA) and compositional nutrient diagnosis (CND) methods revealed that foliar N and P concentrations were limiting to tree growth. Vector analysis (VA) reflected growth responses in fertilized trees, relative to an unfertilized control, but may not be useful as a diagnostic tool due to the indeterminate growth habit of hybrid poplars. Nevertheless, surface application of papermill biosolids and pig slurry had the potential to improve soil fertility by increasing soil pH and extractable nutrients in the hybrid poplar plantations. Nutrient use efficiency (NUE) was greater in plots receiving the mixed biosolids:pig slurry treatment than biosolids or pig slurry alone. Laboratory incubations and 15N isotope pool technique revealed that pig slurry was a source of readily-mineralizable N one month after fertilizer application, and stimulated the gross nitrification rate and immobilization, while papermill biosolids contributed to a larger mineral N pools at the end of the season. Our results suggest that denitrification will be greater in biosolids-treated soils, which have a higher extractable Ca concentration and soil pH, as well as more NO3-N and available C for denitrifiers. Further investigation under field conditions would help us to evaluate the N transformations and losses mediated by microbial activities following organic fertilizer application in a hybrid poplar plantation.
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Urban organic waste in agriculture : risk or resource? /

Johansson, Mats, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

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