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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.
61

Caracterização e análise comparativa de cinzas provenientes da queima de biomassa / Characterization and comparative analysis of ash from biomass burning

Gonzalez, Anselmo Dueñas, 1968- 26 August 2018 (has links)
Orientador: Caio Glauco Sánchez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-26T10:47:21Z (GMT). No. of bitstreams: 1 Gonzalez_AnselmoDuenas_M.pdf: 1368739 bytes, checksum: 0338b09718228f3771fae35aff575d0b (MD5) Previous issue date: 2014 / Resumo: O presente trabalho apresenta o desenvolvimento de um processo de caraterização das cinzas das biomassas bagaço de cana-de-açúcar, eucalipto e capim elefante após sua queima quando utilizadas para geração de energia alternativa. É, então, analisada a influência de parâmetros físico-químicos na qualidade final das cinzas. O parâmetro químico avaliado foi a interpretação da composição elementar das cinzas estudadas por análises de Espectrometria de Fluorescência de Raios-X e Cromatografia de Íons e por Análise Química por, objetivando a caracterização e reutilização desses resíduos. As amostras de cinzas de biomassas estudadas neste trabalho, foram analisadas quanto à presença dos elementos Cloro (Cl-), Alumínio (em Al2O3), Cálcio (em CaO), Ferro (em Fe2O3), Fósforo (em P2O5), Magnésio (em MgO), Manganês (em MnO), Potássio (em K20), Sódio (em Na2O) e Silício (em SiO2), e foram caracterizadas conforme os percentuais em massa dos elementos presentes. Os resultados obtidos mostraram a possibilidade de reutilização adequada de cinzas das biomassas em função da alteração das propriedades químicas do solo, por ocorrência de elevação dos níveis de pH, Cálcio (Ca), Fósforo (P), redução dos teores de Alumínio (Al) trocável e melhoria substancial da capacidade de agregação das partículas e fertilização do solo. Também foram associadas as influências dos elementos presentes nas cinzas como alternativa viável na composição do cimento Portland, em especial, o Silício (em SiO2). As cinzas das biomassas possuem nutrientes que estão na forma solúvel e são libertados ao longo do tempo devido à sua decomposição contínua e também pela solubilidade dos compostos químicos, o que, consequentemente, torna os nutrientes menos suscetíveis à lixiviação / Abstract: This paper presents the development of a process of characterization of the ashes of biomass bagasse from sugar cane, eucalyptus and elephant grass after its burning when used for alternative energy generation. It then analyzed the influence of physicochemical parameters on the final quality of the ash. The chemical parameter evaluated was the interpretation of the elemental composition of the ash studied by analysis Fluorescence Spectrometry X-Ray and Ion Chromatography and Chemical Analysis, aiming at characterization and reuse of the waste. The ashes from biomass samples studied in this work were analyzed for the presence of chlorine (Cl-), aluminum (as Al2O3), calcium (as CaO), iron (as Fe2O3), phosphorus (as P2O5), Magnesium elements (as MgO), manganese (as MnO), Potassium (as K20) Sodium (as Na2O) and silicon (as SiO2), and were characterized as the weight percentage of the elements present. The results showed the possibility of proper reuse of ashes of biomass due to changes in chemical properties of the soil, by the occurrence of elevated levels of pH, calcium (Ca), phosphorus (P), reduced levels of aluminum (l) the significant improvement exchangeable capacity of aggregation of particles and soil fertilization. Were also associated with the influences of the elements present in the ash as a viable alternative in the composition of the Portland cement, in particular, silicon (as SiO2). The ash of the biomass have nutrients that are in soluble form and are released over time due to its continuous decomposition and also by the solubility of the chemical compounds, which consequently makes them less susceptible to leaching nutrients / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica
62

The potential of the agro-processing industry for industrialization in Zambia

Mapulanga, Willard 11 February 2021 (has links)
This study investigates how the development of the agro-food processing industry could support the structural transformation of the Zambian economy. This is set against a backdrop of improved food systems coupled with increased demand for processed foods domestically and regionally, as well as income growth, urbanization, and regional integration. Developing the agro-processing sector will involve the building of dynamic industrial capabilities along with product certification and standards, packaging, logistics, and access to formal markets. Using the value chain of soya beans, the study explains how the development of such a value chain could support structural transformation. Findings suggest that there are numerous opportunities, currently underexploited, for processing soya beans into diversified products. Insights from the study reveal further opportunities to accumulate productive capabilities, both downstream and upstream to stimulate value-addition and export-led growth. Harnessing these opportunities will require specific policy support for soya beans particularly aimed at growing smallholder entry, upgrading agricultural efficiency, engaging government and non-state actors to build capacity to improve processing technologies, food testing, packaging, meeting standards and certification schemes, as well as harmonisation of regional standards.
63

Hållbar skolträdgård : Ett designförslag med skogsträdgården som förebild

Edlund, Karin F January 2021 (has links)
Growing is a creative activity in lower school subject matter. It is an outdoor activity that creates movement. Gardening activities give favorable effects for the social teamwork in studentgroups and cultivation is a way to increase students' awareness of our food production. This argument exists in earlier studies that it is significant when school staff have motivated reasons to create school gardens. Of course, school gardens have always created problems. To get enough resources for management and lesson planning and to handle summer supervision presents in modern times as the largest obstacles for growing activities to work. Against this background, the purpose of this thesis is to find a way forward for gardening as a school activity that increases students' consciousness of sustainable food production.  Forest gardening is a cultivation model within the Agro Forestry movement. Using literature study as a methodology, it is found that forest gardening principles can be applied to school gardening to solve the identified isues with cultivation in primary schools.  Regarding forest gardening principles, one can create a cultivation that occupies a small  area and recieves the ideal microclimate with an array of plants with different hights. This cultivation model lowers the work time required and the need for summer supervision. In addition, this cultivation gives the ecosystem increased biodiversity and carbon storage. Another advantage with this cultivation model is that through plant selection, one can control harvest times to spring and autumn, when students are in school. However, it appears that this cultivation model is knowledge- intensive during the construction phase and that it is a good idea to get outside help from an expert, for example, a gardener with expertise in forest gardening. A design proposal for lower school grades is also included, with a plant list and design plan that can be adapted and suited to schools. / Odling är ett kreativt redskap i grundskolans ämnesundervisning. Det är en utomhusaktivitet som skapar rörelse. Trädgårdsaktiviteter ger gynnsamma effekter för det sociala samspelet i elevgruppen och odling är ett sätt att öka elevernas medvetenhet om vår matproduktion. Dessa argument framgår som betydelsefulla i tidigare studier där skolpersonal har motiverat sina skäl till att  driva skolträdgårdar. Skolträdgårdar har dock i alla tider brottats med problem. Att få resurser att räcka till för skötsel och lektionsplanering och att klara av sommartillsynen, framträder i modern tid som de största hindren för att få odlingarna att fungera. Mot den bakgrunden är syftet med denna uppsats att söka en väg frammåt för skolträdgården, som är hållbar i skolornas verksamhet och som ökar elevernas medvetenhet om en miljömässigt hållbar matproduktion.  Skogsträdgården är en odlingsmodell inom Agro Forestry rörelsen. Med litteraturstudie som metod undersöks här vilka av skogsträdgårdens principer som kan tillämpas i en skoltärdgård för att möta de identifierade problemen för odling inom grundskolan.  Det framgår att man med idéer från skogsträdgården kan skapa en odling som tar en liten yta i anspråk och får ett gynsammt microklimat tack vare växter i olika höjdskickt. Odlingsmodellen kräver en låg skötselinsats i förhållande till skörd tack vare ståndortsanpassning, marktäckning, själförsörjning av näring och perenna grödor som tillsammans minskar behovet av bevattning och skötsel. Resultatet påvisar att man med hjälp av flera av skogsträdgårdens odlingsprinciper kan minska behovet av arbetstid och sommarlovsskötsel. Dessutom ger odlingen ekosystemtjänster som ökad biologisk mångfald och kollagring. Ytterliggare en fördel är att man med hjälp av växtval kan styra skördetiden till vår och höst, då eleverna är på plats i skolan. Det framkommer dock att odlingsmetoden är kunskapskrävande under anläggningsfasen och att det är en god idé att vid etableringen ta hjälp utifrån av expertis som tillexempel en trädgårdsmästare med kompetens inom skogsträdgårdsodling.  Här presenteras också ett designförslag fö en grundskola, med växtlista och design som kan anpassas och modifieras till att passa på flera skolor.
64

High Hill Yak Cheese Production in Nepal: An Analysis of Privatization Policy Incorporating the Impacts of Market Failures for Agro-Industries in Developing Countries

Colavito, Luke A. Jr. 05 September 1997 (has links)
In recent years the development community has pressured LDCs to privatize agro- industries. This pressure stems from poor public enterprise performance and an ideological shift. However, public enterprises mitigate market failures. The major objective of this study is to measure the impact of privatizing the Nepalese yak cheese industry. To achieve the objective, public and private behavior are determined. The impacts of privatization stem from changes in monopsony behavior and institutional constraints that differ between the public and private sectors. The Dairy Development Corporation (DDC) of Nepal produces yak cheese. The DDC's mandate is to provide a "fair" price to consumers and producers. Private producers of cheese have emerged in recent years. Milk shed structures include: single DDC factories, single private factories, multiple private factories, and mixed production. Market performance is evaluated using partial equilibrium models that include the yak cheese and milk markets. Economic surplus measures are used for evaluation. Herder producer surplus is the most important criterion because herders are the poorest beneficiaries. The impact of privatization is determined through comparison of observed DDC and predicted private equilibria. Private equilibrium is predicted using a simultaneous equation system developed for this research. The equations ensure that supply and demand balance at the aggregate and individual milk shed levels. The Lerner index is incorporated to model monopsony behavior. Private monopsony parameters used in the system are estimated econometrically. A private equilibrium is also predicted with a modified firm cost structure reflecting reduced impacts of institutional constraints. Findings show that private and public firms are exercising monopsony power. DDC privatization can be advocated because it increases herder producer surplus by 15.4%. Total surplus falls slightly because private cheese is lower quality. DDC privatization decreases herder welfare in milk sheds that support only a single firm. The simultaneous equation system developed to predict the private market equilibrium for post agro-industry privatization has the potential to be extended to solve a broader range of economic problems. The equation system can be adapted to applications where there are multiple production regions and monopsony behavior varies by regional characteristics. / Ph. D.
65

From agro-waste to encapsulated carbon catalyst for improving stability of naphtha desulfurization

Mohammed, H.R., Hamad, K.I., Gheni, S.A., Aqar, D.Y., Mahomood, M.A., Habeeb, O.A., Ahmed, S.M.R., Rahmanian, Nejat 23 August 2022 (has links)
Yes / The deactivation of the oxidative desulfurization (ODS) catalysts is a challenge and is a major concern in industrial catalytic processes. In this work, an activated carbon (AC) was prepared from agricultural waste and modified to withstand the ODS activity loss over time. The AC was impregnated with manganese and coated with aluminum oxide to prolong the activity lifetime. The catalysts were characterized by nitrogen adsorption-desorption, scanning electron microscope, energy dispersive X-ray, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and transition electron microscope (TEM). The BET surface areas of the examined AC materials were 814.48 m2/g, 784.76 m2/g, and 755.03 m2/g for the AC, Mn/AC, and coated Mn/AC catalysts, respectively with a dominance of microporous pore size. The TGA showed that the coating layer retards the degradation of the active metal and suppresses phase transitions. XRD showed no change in the structure of the catalyst with a coating layer, and from the TEM analysis, the coating layer thickness was 3.6 nm. The kinetics of the ODS catalysts were investigated. It was shown that the ODS reaction follows the first-order kinetics and is not influenced by the coating layer. The activity decay was also investigated. It is found that the activation energy of the deactivation reaction over the coated catalyst was higher than the uncoated catalyst.
66

Immobilisation du phosphore par précipitation induite dans un procédé aérobie à biomasse granulaire / Phosphorus removal and induced precipitation in aerobic granular sludge process for wastewater treatment

Manas Llamas, Angela 16 December 2011 (has links)
Depuis une dizaine d'années, les procédés de granulation aérobie sont apparus comme une technologie prometteuse pour le traitement des effluents fortement chargés en azote, phosphore et carbone, tels que ceux issus de l'agro-industrie. La complexité microbienne de ces granules et les mécanismes qui leur donnent des propriétés exceptionnelles de décantation et de cohésion, constituent encore des axes de recherche importants. Dans cette thèse, le travail s'est axé sur un mécanisme encore non étudié : les processus de précipitation des phosphates au cœur des granules microbiennes. Différentes techniques d'analyses spectrales, parfois adaptés pour la première fois à ce type de systèmes, comme la spectroscopie Raman, ont permis de caractériser la nature de ces minéraux formés au cœur des granules. L'analyse menée sur des réacteurs de laboratoires a démontré la présence des phosphates de calcium sous forme d'hydroxyapatite [Ca5(PO4)3(OH)]. Cette précipitation est potentiellement induite par les variations locales de pH et de sursaturation provoqués par les réactions microbiennes à l'intérieur des granules. L'étude des phénomènes de biominéralisation à été étendu aux granules anaérobies issus des réacteurs de type UASB de l'industrie laitière. Un modèle physico-chimique sur les processus de précipitation sous forme matriciel sur AQUASIM®, couplé avec des bases de calcul de sursaturation (PHREEQC®), ont permis d'avancer des hypothèses sur les mécanismes influençant ces processus de biominéralisation, tels que la formation d'un précurseur amorphe de l'hydroxyapatite (ACP), ainsi que d'identifier les constantes de précipitation thermodynamiques (pKsp|20ºC=28.07±0.58) et cinétiques dans différentes conditions opératoires. Grâce au suivi d'un système biologique GSBR (Granular Sludge Sequenced Batch Reactor) pendant plus de 900 jours, la contribution de ce phénomène aux processus de déphosphatation a été estimé (46% dans les conditions testées). L'utilisation de ce processus pour immobiliser efficacement le phosphore et apporter des propriétés physiques stables aux granules a été également discutée. Une évaluation des performances et de la stabilité du réacteur à été mis en œuvre en alternant des cycles anoxies/aérobies ou anaérobies/aérobies vis-à-vis d'une future application industrielle. L'induction locale de la précipitation par les variations de pH et par le relargage des phosphates par les réactions microbiennes, nécessite une modélisation appropriée, qui a été également initiée dans cette thèse / Over the last decade, aerobic granulation processes have araised as a promising technology for treating wastewater effluents containing high nitrogen, phosphorus and carbon concentrations. The microbial complexity of granules and the mechanisms by which they acquire excellent settleability properties, still constitute important research goals to investigate. This thesis is focused on a mechanism that has been little addressed in literature, that is, phosphate precipitation in the core of aerobic granules. Different analytical techniques, sometimes adapted for the first time to this type of systems, like Raman spectroscopy, have let an exhaustive characterization of biominerals in the core of granules. Analyses performed on aerobic granules grown with synthetic fed in a lab-scale SBR (Sequential Batch Reactor), revealed a calcium phosphate core made of hydroxyapatite [Ca5(PO4)3(OH)]. This precipitation phenomenon is induced by local pH and supersaturation gradients issued of biological reactions inside granules. The study of the biomineralization phenomenon has been extended into anaerobic granules coming from UASB reactors at different cheese wastewater treatment plants. A physico-chemical model has been described in a form of matrix with AQUASIM® software, and coupled with a thermodynamic database (PHREEQC®), in an attempt to hypothesize the mechanisms that influence the biomineralization phenomena. It has been proposed the formation of an amorphous precursor (ACP) prior hydroxyapatite precipitation in the core of granules, suggesting the thermodynamic constant (pKsp|20ºC=28.07±0.58) and kinetic constants at different operating conditions. It has been also estimated the contribution of the biomineralization to the overall phosphorus removal process (up to 46% at the operating conditions tested), thanks to the development and study of a GSBR (Granular Sludge Batch Reactor) in labscale, for more than 900 days. The fate of the biomineralization process in granules, regarding the contribution to their stabilization and physical properties, has been also dealt in this thesis. The reactor stability and performances have been assessed by alternating anoxic/aerobic and anaerobic/aerobic cycles, in sights of a future industrial application. The induction of precipitation by local variation of pH and supersaturation issued of biological reactions has been here introduced, although it will need further investigation
67

Production d'hémicelluloses de pailles et de sons de blé à une échelle pilote. Etude des performances techniques et évaluation environnementale d'un agro-procédé / Production of hemicelluloses from wheat straw and bran at pilote scale : Technical and environmental performances evaluation

Jacquemin, Leslie 12 December 2012 (has links)
L'objectif de ces travaux vise à évaluer les performances techniques et environnementales d'un procédé de fractionnement et de purification d'hémicelluloses de pailles et sons de blé. La démarche employée consiste dans un premier temps à évaluer la faisabilité du procédé à une échelle pilote. Celui-ci implique notamment une opération de fractionnement par extrusion bi-vis et des étapes de concentration-purification par une combinaison d'ultrafiltration et de chromatographie sur résine. Il est comparé à un procédé plus classique où l'extrait extrudé subit une évaporation et une précipitation éthanolique. L'étude des compositions chimiques des extraits et des poudres produites à chaque étape du procédé permet d'observer que l'extrusion bi-vis donne des rendements plus faibles que d'autres techniques d'extraction, mais présente des avantages en termes d'échelle, de continuité du procédé, et de faibles consommations d'eau. Par ailleurs, l'ultrafiltration est une technique intéressante car elle permet une purification et une concentration des extraits simultanées et la chromatographie sur résine s'est avérée être une solution attractive pour la décoloration des extraits. Dans un second temps, la méthodologie d'analyse du cycle de vie (ACV) a été appliquée au procédé. Celle-ci a mis en avant le fort impact environnemental généré par certaines opérations unitaires et a donné lieu à l'identification de priorités d'actions pour l'amélioration du procédé. Ainsi, le scénario mettant en jeu une combinaison de l'ultrafiltration avec une chromatographie sur résine semble plus avantageux que celui mettant en jeu une évaporation sous vide combinée à une précipitation éthanolique. La démarche employée apporte également des réponses méthodologiques sur la démarche d'ACV appliquée aux procédés : l'importance de prendre en compte différentes méthodes de caractérisation, de tester la sensibilité de l'étude à l'unité fonctionnelle et aux hypothèses initiales ont été mises en avant. Enfin, dans le but de démontrer sa forte potentialité dans le domaine des procédés, l'ACV a été appliquée à certaines opérations unitaires. L'intérêt d'étudier l'influence des conditions opératoires des procédés sur les impacts environnementaux a été démontré. Par ailleurs, la nécessité de développer des outils de modélisation des procédés qui pourront être couplés à ceux de l'ACV afin d'intégrer pleinement les critères environnementaux au dimensionnement des procédés a été mis en avant. / The objective of this work was to evaluate the technical and environmental performance of a fractionation and purification process of hemicelluloses from wheat straw and bran. The approach used was first to assess the feasibility of the process on a pilot scale. This implied setting up twin-screw extrusion, concentration steps by ultrafiltration and a purification step by ion exchange chromatography. It was compared to a more traditional process where the extruded extract was treated by evaporation and ethanol precipitation. Study of the chemical composition of extracts and powders produced at each stage of the process, showed that the twin-screw extrusion gave lower yields than other extraction techniques, but had the advantage in terms of scale, continuity of the process and low water consumption. Furthermore, ultrafiltration is an interesting technique because it allows simultaneous purification and concentration of the extracts, and ion exchange chromatography proved to be an attractive solution for the removal of coloured compounds. In a second step, the life cycle assessment (LCA) methodology was applied to the process. This highlighted the strong environmental impact generated by some unit operations, and resulted in the identification of priorities to improve the process. Thus, the scenario involving a combination of ultrafiltration with ion exchange chromatography appears to be more advantageous than that involving vacuum evaporation combined with ethanol precipitation. The approach used also provides methodological answers for LCA applied to processes: the importance of taking into account different characterization methods, testing the sensitivity of the study to the functional unit, and reconsidering the initial assumptions, has been stressed. Finally, in order to demonstrate its high potential in the field of processes, LCA has been applied to some unit operations. The interest of studying the influence of process operating conditions on environmental impacts has been demonstrated. In addition, the need to develop tools for modelling processes that can be coupled to those of LCA in order to fully integrate environmental criteria into process design, has been highlighted.
68

Microbial assemblage in grapevine's phyllosphere : who is the driver ? / Assemblage microbien dans la phyllosphère de la vigne : qui est le pilote ?

Singh, Prashant 30 November 2018 (has links)
Vitis vinifera subsp. vinifera L., les principales espèces de raisins sont cultivées pour la production de fruits et la production de vin dans le monde est un hôte naturel d'une grande variété de micro-organismes procaryotes et eucaryotes qui interagissent avec la vigne, ayant des effets bénéfiques ou phytopathogènes. Ils pourraient également jouer un rôle majeur dans le rendement des fruits, la qualité du raisin, la protection des plantes et, finalement, dans le modèle de la fermentation du raisin et la production de vin. La phyllosphère (constituée des parties aériennes de la plante) est l'un des habitats microbiens les plus répandus sur terre et est un milieu assez négligé, en particulier dans les vignes et de nombreuses questions liées à cet habitat microbien sont toujours sans réponse.Cette thèse est un effort pour répondre à une question fondamentale en écologie microbienne: quels sont les facteurs qui déterminent le microbiome dans la phyllosphère de la vigne? Les communautés microbiennes de la phyllosphère (PMCs) vivent à l'interface plante-climat et sa capacité à s'établir, prospérer et se reproduire sur la surface des feuilles ou des fruits dépend de plusieurs caractéristiques fonctionnelles microbiennes, comme la capacité de se fixer sur la cuticule et d'utiliser la foliaire. nutriments ainsi que les conditions climatiques dominantes comme la température, l'humidité de l'air et la pluie. La chimie des feuilles ou des fruits, la physiologie et la structure morphologique diffèrent selon le génotype et l'espèce puisque tous ces traits ont une base génétique, et cette variation peut mener à une combinaison différente d'assemblage de PMC parmi les génotypes de plantes. Ainsi, le premier objectif de notre travail était d'évaluer les impacts des cultivars de vigne (variétés de Vitis vinifera L) et des espèces de vigne (espèces Vitis entièrement différentes) sur l'assemblage du microbiome dans la phyllosphère à un endroit géographique particulier (pour minimiser les effets environnementaux) . Plus tard, les impacts de certains cultivars et terroirs de vigne commercialement importants (représentés par trois zones climatiques françaises) ont également été évalués et comparés. Les impacts de la saison et des organes extérieurs de la plante (feuilles et baies) sur la structuration des taxons microbiens dans la phyllosphère ont également été évalués et présentés dans ce travail. De plus, des impacts spécifiques à l'espèce sur le microbiome de la phyllosphère ont également été testés et représentés.Dans l'ensemble, notre étude a évalué et comparé les nombreuses facettes des facteurs qui peuvent influencer structure du microbiome dans la phyllosphère avec un accent particulier sur la pression de sélection relative exercée par le génotype de la vigne et son interaction avec différentes conditions climatiques (ou terroir), ce qui peut améliorer nos chances de trouver des gènes contrôlant les PMCs sur la phyllosphère. les gènes sont réellement importants dans des environnements réalistes et probablement ces gènes nous donneraient de nouvelles idées pour la sélection de nouveaux cépages sains présentant de meilleurs caractères sur leur phyllosphère. De plus, considérant que les PMC végétales jouent un rôle crucial dans la santé et la forme des plantes car elles peuvent moduler la susceptibilité foliaire aux infections, cette étude pourrait également être utile pour développer des méthodes de biocontrôle innovantes et naturelles ou phytostimulation contre les pathogènes de la vigne. de variétés résistantes innovantes. / Vitis vinifera subsp. vinifera L., the main grape species are grown for fruit and wine production over the world is a natural host of a wide variety of prokaryotic and eukaryotic microorganisms that interact with grapevine, having either beneficial or phytopathogenic effects. They could also play a major role in fruit yield, grape quality, plant protection and, ultimately, in the pattern of grape fermentation and wine production. Phyllosphere (consists of the aerial parts of the plant) is one of the most prevalent microbial habitats on earth and is quite a neglected milieu, especially in grapevines and many questions related to this microbial habitat, are still unanswered.This thesis is an effort to answer a very fundamental question in microbial ecology- what are the drivers that shape the microbiome in the grapevine's phyllosphere? The phyllosphere microbial communities (PMCs) live at the plant-climate interface and its ability to establish, thrive and reproduce on the leaf or fruit surface depends on several microbial functional traits, such as the ability to attach to the cuticle and to use the foliar nutrients as well as well as to the prevailing climatic conditions like temperature, air humidity and rain. Leaf or fruit chemistry, physiology, and morphological structure differ among plant genotype and species as all these traits have a genetic basis, and this variation may lead to a different combination of PMCs assemblage among plant genotypes. Hence, the first objective of our work was to assess the impacts of grapevine cultivars (varieties of Vitis vinifera L) and grapevine species (entirely different Vitis species) on microbiome assemblage in the phyllosphere at a particular geographic location (to minimize the environmental effects). Later on, impacts of some commercially important grapevine cultivars and terroirs (represented by three French climate zones) were also assessed and compared. Impacts of the season and exterior plant organs (leaf and berries) on microbial taxa structuring in the phyllosphere was also assessed and presented in this work. Furthermore, species-specific impacts on phyllosphere microbiome were also tested and represented.Overall our study assessed and compared the many facets of the factors that may influence themicrobiome structure in the phyllosphere with a special focus on relative selection pressure exerted by grapevine genotype and its interaction with different climatic conditions (or terroir), which may improve our chances to find genes that controls PMCs on phyllosphere, and simultaneously increase our confidence that those genes are actually important in realistic environments and probably those genes would give us new insights for breeding new and healthy grape varieties displaying better traits on their phyllosphere. Moreover, considering that the plant PMCs plays a crucial role in plant health and fitness as it can modulate leaf susceptibility to infection, this study could also be helpful to develop innovative and natural biocontrol methods or phytostimulation against grapevine pathogens or rethink breeding schemes for the creation of innovative resistant varieties.
69

Cobertura florestal vs. isolamento: efeito da paisagem sobre a provisão do serviço de polinização ao café. / Forest cover vs. forest isolation: the landscape effect on pollination service supply, demand and flow to coffee crop

Gonzalez Chaves, Adrian David 29 July 2016 (has links)
Na medida em que as demandas agrícolas continuam se expandido, aumenta a necessidade de que a produção agrícola garanta a conservação da diversidade e a provisão de serviços ecossistêmicos. O intuito do trabalho é avaliar independentemente o efeito da distancia aos fragmentos florestais e a cobertura florestal numa escala local. Quantificamos a diversidade de abelhas e a formação de frutos em 24 cultivos de café dentro de paisagens complexas de 2km de radio, compostas por mosaico de usos da terra, café, Mata Atlântica (20 - 27%) e outros usos. Adicionalmente estimamos a contribuição das espécies na formação de frutos depois de uma visita única, em cinco dos 24 pontos amostrais. No total foram identificadas 31 abelhas que visitam o café, a maioria abelhas sem ferrão (Meliponini) e abelhas da família Halictidae. No existiu diferencia na formação de frutos depois das visitas únicas das diversas especies de abelhas, o que sugere que há uma complementaridade na provisão do serviço. No entanto, a maior produtividade esteve associada à abundância de abelhas nativas. Em geral, 8% foi o incremento associado ao papel das abelhas o qual diminuiu com aumento da distancia para os fragmentos de mata assim como também conforme aumentava a quantidade de café na escala local (400 m de raio no entorno do ponto amostral). O efeito negativo da distancia aos fragmentos reforça a importância da vegetação natural em prover diversidade de abelhas e por tanto o serviço de polinização. O efeito negativo da cobertura de café sobre a frutificação sugere que há um excesso de demanda que excede a capacidade dos polinizadores de prover o serviço dentro de paisagens complexas. Nossos resultados mostram que a estrutura da paisagem afeta a densidade, riqueza e composição de espécies de polinizadores. Por tanto recomendamos como estratégia para incrementar a produção de café, sem necessidade de aumentar a cobertura florestal, manegar as áreas agrícolas para aumentar a dispersão entre fragmentos florestais e plantios de café, com o intuito de criar paisagens mais fragmentadas que facilitem o fluxo de polinizadores ao café / As the demands on agricultural lands continue to expand, effective strategies are urgently needed to manage agricultural production to guarantee biodiversity conservation and ecosystem service provision. Here we assessed independently the effect of forest isolation and local forest cover over bee diversity and on the provision of pollination service to coffee. We quantified bee diversity of flower visitors and fruit set in 24 coffee fields within three complex landscape of 2km radius surrounded by mosaic of coffee plantations, Atlantic forest fragments (20 - 27%), pastures and other lands uses. Additionally, we estimated species contribution to fruit set after single visit in five of the 24 coffee sites. In total we identified 31 bee species visiting coffee flowers, most being stingless bees (Meliponini tribe) and sweat bees (Halictidae). The absence of difference in fruit set after single visit by Apis and natives bee suggest that service complementation. Although, higher abundances of sweat bees and stingless bees were positively related to fruit set. Coffee fruit set was overall 8% higher in the presence of bees, and responded negatively to isolation from forest fragments and to high coffee cover at a local landscape scale (400 m radius landscape surrounding each sampled coffee bush). The negative association between isolation and fruit set reinforces the importance of natural vegetation to enhance bee diversity and therefore the provision of pollination service. The negative effect of coffee cover on fruit set suggests that the service demand can surpass pollinators\' capacity to provide service within complex landscape. Our results provide clear evidences that landscape structure can affect the abundance, richness and composition of pollinators\' species, and thus can indirectly regulate the provision of pollination service. Therefore we recommend, as a strategy to increase coffee yields without necessarily expanding forest cover, to manage agricultural landscapes in order to increase interspersion between forest fragments and coffee plantation thus a more patchy landscape mosaic that may facilitate pollinators flows to coffee crop
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A agroecologia como alternativa frente à modernização da agricultura: um estudo de caso no município de Coronel Vivida PR / The agro-ecology alternative faced on the agriculture modernization: a case report in Coronel Vivida town

Stasiak, Ana Paula 08 July 2013 (has links)
Made available in DSpace on 2017-05-12T14:41:54Z (GMT). No. of bitstreams: 1 Ana_Paula_Stasiak.pdf: 6576934 bytes, checksum: 2a7f5dfaa2eccfd9cce5a56afda8f804 (MD5) Previous issue date: 2013-07-08 / The agro-ecological farming has got started by social movements in favor to the rural sustainable development based on environmental, social and economic. Agroecologyis presented as an alternative to modernization of agriculture that repair environmental damage and social damage caused by the green revolution technology disseminated and adopted by the Brazilian government as a development policy based on the economic growth. This paper aims to analyze the agro-ecology alternatively forward the modernization process of the agriculture and the different territorialities provided by the two forms of production, as well as identify the limits and difficulties of territorial agro-ecological practices in Coronel Vivida, held bibliographic review the topic addressed and fieldwork, using a questionnaire addressed to eleven farmers who have comprised three distinct groups related to agro-ecology in the town: Farmers Convention with SAFs; 2) Agro-ecological Farmers; 3) Farmers Convention-Former Agro-ecological Farmers. And interviews with representatives of institutions related to agriculture and agroecology family whose work is in the town. The study of these three groups with different production and commercial organizations had allowed us to observe the process of territorialization and deterritorialization of simultaneous agro-ecological practices, the latter prevails. Another methodology used to characterize the properties sustainable, based on agro-ecological principles, as well as differentiate the analysis was made landscapes through sketches and photographs of the properties studied. This paper outlines the main difficulties faced by the town farmers relationed to agro-ecological production, as well as the main factors which have influenced the abandonment of agro-ecological practices by the Coronel Vivida agro-ecological farmers. / A agricultura agroecológica surge de movimentos sociais em favor de um desenvolvimento rural sustentável, baseado nas condições ambientais, sociais e econômicas. A Agroecologia é apresentada como alternativa a modernização da agricultura visando reparar os danos ambientais e prejuízos sociais causados pela tecnologia disseminada pela revolução verde e adotada pelo Estado brasileiro como política desenvolvimentista baseada no crescimento econômico. Com o objetivo de analisar a Agroecologia como alternativa frente ao processo de modernização da agricultura e as diferentes territorialidades proporcionadas pelas duas formas de produção, assim como, identificar os limites e dificuldades de territorialização das práticas agroecológicas em Coronel Vivida, realizou-se revisão bibliográfica sobre o tema abordado e trabalho de campo, com aplicação de questionário dirigido à onze agricultores familiares que compõem três grupos distintos relacionados com a Agroecologia no município: 1) Agricultores Convencionais com SAFs; 2)Agricultores Agroecológicos; 3)Agricultores Convencionais Ex-Agricultores Agroecológicos. E entrevistas com representantes de instituições ligadas a agricultura familiar e a Agroecologia que atuam no município. O estudo desses três grupos que apresentaram organizações produtivas e comerciais diferentes nos permitiu constatar o processo de territorialização e desterritorialização simultâneas das práticas agroecológicas, prevalecendo esse último. Outra metodologia utilizada para caracterizar os estabelecimentos sustentáveis, baseados nos princípios agroecológicos, assim como, diferenciar as paisagens constituídas foi à análise através de croquis e fotografias dos estabelecimentos em estudo. O presente texto aponta as principais dificuldades enfrentadas pelos agricultores do município em relação à produção agroecológica, assim como, os principais fatores que influenciaram no abandono de práticas agroecológicas por parte dos ex-agricultores agroecológicos de Coronel Vivida.

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