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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.
131

Competitividade da viticultura regional e brasileira: uma análise setorial e comparativa com produtores mundiais / Competitiveness of regional and braziliam viticulture: a sectoral analysis with world producers

Julião, Letícia 08 October 2015 (has links)
O setor agrícola brasileiro gera saldos positivos à balança comercial do Brasil, e a fruticultura segue no mesmo ritmo. Dentre as frutas produzidas no Brasil, a uva é uma das que mais impactam na balança comercial, tendo em vista que é amplamente exportada e importada. Este cenário só se tornou possível com a abertura de mercado na década de 90, e, assim, o Brasil pôde se tornar mais competitivo no mercado nacional e internacional. A competitividade é importante para a economia, seja de um país, de um setor ou de uma empresa. No presente trabalho, então, foi realizada uma análise setorial da competitividade da viticultura, fundamentada na produtividade, nos aspectos tecnológicos e no ambiente institucional. Para a análise regional brasileira foi utilizada a técnica de triangulação na metodologia deste trabalho: pesquisa qualitativa (entrevista com produtores das principais regiões produtoras de uva de mesa do Brasil); análise estatística por meio de Modelos Lineares Generalizados de dados secundários (preço nas regiões produtoras de uva de mesa) obtidos no banco de dados do Cepea; e análise documental (com base nas legislações, regras e outros documentos disponíveis). A partir disso foi constatado que o Vale do São Francisco (BA/PE) é a região brasileira mais competitiva, visto que investe mais em tecnologia, tem gestão empresarial (enquanto as outras são marcadas pela agricultura familiar) e consegue se sobressair nas questões de comercialização. Além disso, no Brasil, o ambiente institucional, de um modo geral, não gera grandes vantagens competitivas para nenhum produtor de uva - a exceção são as fortes cooperativas do Nordeste. Para a análise da competitividade internacional, além da análise documental com vistas ao comércio internacional, foram feitas estatísticas descritivas com dados de preço, produção, produtividade, exportação, importação e consumo aparente de uva de mesa do Brasil, Chile e Itália. Os dados foram obtidos nos bancos de dados do IBGE, MDIC, Odepa, Eurostat e USDA. No geral, Chile e Itália têm ambiente institucional mais forte que o Brasil para o comércio internacional de uva de mesa. Mesmo assim, a competitividade internacional brasileira cresceu nos últimos anos frente a Chile e Itália. Assim, pode-se concluir que mesmo com ambiente institucional desfavorável, tanto no mercado interno quanto no externo, o Brasil conseguiu avançar na competitividade entre os anos analisados neste trabalho. Isso se deve, sobretudo, aos investimentos ocorridos na principal região brasileira - o Vale do São Francisco. / The Brazilian agribusiness generates profits to the trade balance of Brazil, and the fruit sector follows the same rhythm. The table grape is one of the fruits that impact the trade balance, because it is widely exported and imported. This scenario was only possible to the market opening in the 90s, and thus Brazil was able to become more competitive in domestic and international markets. Competitiveness is important to the economy, whether of a country, of a sector or a company. Thus, a sectorial analysis of the viticulture competitiveness was conducted, based on productivity, technological and institutional environment. In this research, it was used triangulation technique in the methodology to conduct the Brazilian regional analysis: qualitative research (interview with producers of the main producing regions of table grape of Brazil); statistical analysis using Generalized Linear Models of secondary data (price of table grape) obtained in Cepea database; and documental analysis (based on the laws, rules and other documents available). Based on this, it was found that the São Francisco Valley (BA/PE) is the most competitive region in Brazil. This region invests more in technology, has business management (while the others regions are tagged by family farmers) and stands out in the marketing. In addition, in Brazil, the institutional environment, in general, does not generate competitive advantages for grape growers - the exception is the strong cooperatives located in Northeast. The international competitiveness was conducted by descriptive analysis of statistics - price, production, productivity, export, import and apparent consumption of table grape in Brazil, Chile and Italy. Also, a documental analysis of international trade was conducted. Data were obtained from the IBGE, MDIC, Odepa, Eurostat and USDA databases. Overall, Chile and Italy have a stronger institutional environment to international trade of table grapes than Brazil. Anyway, the Brazilian international competitiveness has increased in recent years compared to Chile and Italy. Thus, it can be concluded that even with unfavorable institutional environment, both domestically and external, Brazil was able to advance in competitiveness during the years analyzed in this work. This is mainly attributed to the investments occurred in the main Brazilian table grape region - São Francisco Valley.
132

Dinâmica locacional da vitivinicultura: novas regiões do Rio Grande do Sul e Vale do São Francisco / Locational dinamic of viticulture: new production areas in the state of Rio Grande do Sul and Vale do São Francisco

Schneider, Luciane 31 August 2006 (has links)
Este estudo teve como objetivo central identificar quais fatores locacionais influenciaram a tomada de decisão de expandir os investimentos da atividade vitivinícola por parte dos empresários atuantes na Serra Gaúcha - principal pólo vitivinícola do país. Observou-se um movimento de expansão territorial da atividade vitivinícola para novas regiões do Rio Grande do Sul (Serra do Sudeste e Campanha) e para o Vale do São Francisco (Bahia e Pernambuco), regiões em que, anteriormente, não havia a prática de tal cultura. As informações da presente pesquisa foram obtidas através de entrevista direta, orientada por um questionário, com representantes das vinícolas. A abrangência da pesquisa foi de 73,3% da população alvo e foi realizada nos meses de dezembro/2005 no Rio Grande do Sul e janeiro/2006 no Vale do São Francisco. Os dados das entrevistas foram tratados com aplicação da estatística descritiva, pois grande parte das perguntas foi de ordem qualitativa. A hipótese que circunda este estudo é de que na agroindústria, as variáveis que envolvem a matéria-prima (qualidade, local de fornecimento) são os principais fatores que influenciam a tomada de decisão do sítio de produção. Como referencial teórico, associou-se as teorias relacionadas aos fatores locacionais com a teoria de Bowersox (1978). Através da pesquisa, pode-se verificar que a atividade vitivinícola brasileira mostrou estar condicionada à distribuição espacial dos recursos produtivos, destacando-se os fatores edafoclimáticos, qualidade da matéria-prima, fator comportamental do empresário e disponibilidade de terras. A pesquisa revelou que as empresas estão preocupadas com a qualidade final do produto (vinho), a qual é otimizada pela qualidade da matéria-prima (uva) que, por sua vez, depende das condições edafoclimáticas da região produtiva. Tal preocupação e/ou necessidade provocou esta expansão geográfica da atividade para a Serra do Sudeste e Campanha (no estado do Rio Grande do Sul) e no Vale do São Francisco. Esta última região também se mostrou alvo de investimentos estrangeiros e tornou-se (e ainda se torna) atrativa por apresentar excelentes condições edafoclimáticas, capacidade de duas safras por ano e produção constante no decorrer do ano, além de instalações processadoras de menor porte. / The purpose of this work is to identify which locational variables influenced the decision made by producers from the state of Rio Grande do Sul (RS), main viticulturist state in Brasil, to expand investments on the wine industry. There was a movement of territorial expansion of wine production to new regions in RS (Serra do Sudeste and Campanha) and to Vale do São Francisco, in the states of Bahia and Pernambuco, regions in which he grape agriculture hadrit started yet. The direct-interview with viticulturists was the main source of information used by this work. This research embraced 73,3% of the producers investing in those new regions, and it was conducted during December/2005, in the State of Rio Grande do Sul, and January/2006, in Vale do São Francisco. Descriptive statistic has been applied to summarize the data obtained with the interviews, due to qualitative variables representing most of the questions. The main hypothesis of this work suggests that in the agroindustry, variables involving raw material (quality, supplier) are the main factors in making the decision as to production area. A review of Bowersox Theory (1978) associated with the theory of locational factors was employed as theoretical referential. As for results, it was possible to validate that Brazilian viticulture was conditioned to the place distribution of productive resources, standing out the following factors: edaphoclimatics, raw material quality, manager behavior and land availability. Thus, the research revealed that companies have been concerned regarding the quality of the final product (wine), which is optimized through raw material quality (grape) that depends on edaphoclimatic conditions of the productive area. Indeed, the need to achieve a higher level of quality forced the viticulture to expand its production area to Serra do Sudeste and Campanha (RS) and Vale do São Francisco, which has recently turned into an attractive area to foreign investment, because of its excellent edaphoclimatic conditions, two harvests a year, continuous output year round and a small agroindustry.
133

Imagerie radar en ondes millimétriques appliquée à la viticulture

Henry, Dominique 29 May 2018 (has links) (PDF)
Avec l’expansion des exploitations agricoles, le principe d’homogénéité du rendement (céréales, fruits…) devient de moins en moins pertinent. Ce phénomène de variabilité spatiale implique des conséquences économiques et environnementales avec le développement de nouveaux concepts agricoles comme les « site-specific management » (gestion spécifique des parcelles). Les traitements tels que les fertilisants, les intrants et autres pesticides doivent être utilisés de manière différente en les appliquant au bon endroit, à la bonne période et au bon taux. Cette nouvelle façon de penser l’agriculture fait partie de l’agriculture de précision (PA) et se concentre en quatre domaines technologiques : (i) la télédétection, (ii) la navigation et guidage, (iii) la gestion des données et (iv) les technologies à taux variable. Initiée à la fin des années 1990, la viticulture de précision (PV) est une branche particulière de la PA, caractérisée par des problématiques spécifiques à la viticulture. Les travaux effectués durant cette thèse entrent dans le cadre de la télédétection (ou détection proche) appliquée à la PV. Ils se focalisent sur une nouvelle méthode d’estimation de la quantité de grappes (masse ou volume) directement sur les plants de vignes. Pouvoir estimer le rendement des vignes plusieurs semaines avant la récolte offre de nombreux avantages avec des impacts économiques et qualitatifs, avec par exemple : (i) l’amélioration du rapport rendement/qualité en supprimant au plut tôt une partie de la récolte, (ii) l’optimisation des ressources humaines et la logistique à la récolte, (iii) un remboursement le plus équitable par les assurances en cas d’intempéries qui endommageraient les pieds de vignes. La méthode proposée ici repose sur l’imagerie microondes (à 24GHz ou des fréquences plus élevées) générée par un radar FM-CW. Elle implique la mise en place d’un système d’interrogation intra-parcellaire « pied par pied » à distance basé au sol, et en particulier : (i) l’évaluation de la précision des mesures et les limites du système, (ii) le développement d’algorithmes spécifiques pour l’analyse de données tridimensionnelles, (iii) la construction d’estimateurs pour retrouver le volume des grappes, et finalement (iv) l’analyse des données recueillies pendant les campagnes de mesures. Dû au caractère saisonnier des récoltes, les mesures sont en premier lieu effectuées sur des cibles canoniques, des charges variables et des capteurs passifs en laboratoire. Pour mettre en avant la flexibilité de cette interrogation radar, le même système est utilisé en parallèlement dans le cadre du projet régional PRESTIGE, pour compter à distance le nombre de pommes présentes sur les pommiers en verger. Ces travaux ont été financés par l’entreprise Ovalie-Innovation et l’ANRT (Agence Nationale de la Recherche Technologique).
134

Physiology and biochemistry of budburst in Vitis vinifera

Campbell, James Alexander, mikewood@deakin.edu.au January 1993 (has links)
Both the physiological and biochemical control of budburst in the grapevine, Vitis Vinifera L. were investigated. It was found that the accuracy of a predictive model for grapevine budburst based on ambient temperature was limited under the experimental conditions. There was a significant correlation of 4.7 ± 0.3 days between the days of maximal xylem exudation and budburst over the 3 years of investigation. The co-relationships between daily xylem exudate volume and a range of environmental parameters were considered. It was found that soil temperature was highly correlated against daily xylem exudation. Ambient temperature and soil moisture were significantly correlated with xylem exudation, however the coefficients of correlation were much lower than that of soil temperature. Rainfall showed only a very limited correlation with daily xylem exudate flow. Seasonal variations in the pH and the carbohydrate and inorganic nutrient concentrations of xylem exudate were investigated. Exudate carbohydrate concentrations fell from 660 µM before the day of maximal xylem exudation to zero levels within 4 weeks. Xylem exudate pH was found to consistently fall to a minimum at the time of maximal exudate flow. Exudate concentrations of the metallic cofactors Ca, K, Mg, Mn and Zn varied directly with daily exudate flow, suggesting some sort of flow-dependent mobilisation of these nutrients. A growth promontory oligosaccharide fraction was prepared by partial acid hydrolysis of grapevine primary cell wall material. This fraction significantly increased control growth of the Lemna minor L. bioassay over a limited ‘window’ of bioactivity. A growth inhibitory oligosaccharide fraction, similar in activity to abscisic acid was isolated from grapevine xylem exudate prior to budburst. The exudate concentration or efficacy of this substance declined after budburst such that there was no apparent growth inhibition. A model is proposed for grapevine budburst whereby an oligosaccharide growth inhibitor is gradually removed from the xylematic stream under the effects of soil temperature, allowing the surge of metabolic activity and vegetative growth that constitute budburst.
135

Utility Of The American Viticultural Areas Of Texas Information Systems (AVATXIS) As A Tool In The Characterization Of The Texas Wine Regions

Takow, Elvis 16 January 2010 (has links)
Geographic Information System (GIS) based computer applications are becoming increasingly popular for delivering, visualizing and analyzing spatial databases. Driven by advances in computing technologies, GIS applications are increasingly used by non- GIS experts as knowledge support tools that allow instant access and visualization of spatial data across the internet. The American Viticultural areas of Texas (AVATXIS) is an example of a web-based GIS tool that we have developed to help viticulturists better understand wine growing regions in Texas. The application allows users to spatially query and visualize a range of edaphic and climatic factors that influence vine growth and grape production. By providing growers a wide variety of climatic and edaphic data sets and an intuitive, easy to use interface for visualizing and downloading this data, AVATXIS serves as an effective tool for characterizing the Texas wine regions. Research in the field of viticulture states that ?Climate governs whether grapes will survive and ripen, what varieties do best where, and some of the characteristics of the resulting wines?. For AVATXIS, a number of specific climate indices critical to wine production were identified through the current viticulture literature and by consulting with experts. These indices include monthly summaries of maximum, minimum and mean temperature, precipitation and Growing Degree-Days (GDD). Publicly available climate data was used to create novel GIS layers for each of these indices. Similarly the importance of soil type to vine growth is recognized, but its relationship to wine quality remains controversial. Publicly available soil data were used to create GIS layers representing simple soil indices (pH, soil texture, depth to bedrock, permeability, available water capacity, and bulk density) useful to the wine grower. These climate and soils data form the central database used by AVATXIS. The intuitive, user interface allows any combination of these GIS layers to be rapidly retrieved and visualized through a standard web-browser by any user of the AVATXIS system.
136

Unfree labour? : Ni-Vanuatu workers in New Zealand's recognised seasonal employer scheme : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Arts in Anthropology in the University of Canterbury /

Bailey, Rochelle-lee. January 2009 (has links)
Thesis (M.A.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 167-178). Also available via the World Wide Web.
137

Growing Grapes in Arizona

Tate, Harvey F., Milne, Ray L. 07 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
138

Malate and tartrate in Oregon grapes

Norton, Kerry M. 01 May 1987 (has links)
In western Oregon the titratable acidity of grapes at harvest may in some seasons be higher than desirable for making quality wine, due to the retention of malic acid. The purposes of this study were 1) to investigate the effects of a vineyard cultural practice, cluster exposure at veraison by basal leaf removal, as a means of reducing the malate content and titratable acidity of grapes, and 2) to develop a rapid, simple, and inexpensive test procedure by which smaller wineries and vineyards could evaluate the effects of their own field experiments on the malate and tartrate content of their grapes. 1. At veraison, clusters of Chardonnay grapes were a) exposed to the sun by removal of all leaves opposite or below the clusters, b) treated as in a) but shaded with shadecloth, c) exposed to the sun by tying back leaves opposite or below the clusters, or d) left untreated as a control. Clusters of White Riesling were exposed to the sun by similar leaf removal a) 10 days before veraison, b) 10 days after veraison, or c) untreated. Clusters of Pinot Noir were exposed a) at veraison, b) 2 weeks after veraison, or c) untreated. Exposed clusters received 3 to 3.5 times more light than shaded clusters and up to 32% more heat, with temperature differences between exposed and shaded treatments being most pronounced during cool, sunny weather. None of the treatments had any effect on juice or berry malate, tartrate, or potassium content; however, exposed clusters of Pinot Noir had a lower pH (.03) and higher titratable acidity (.06%) than the control at harvest. Cluster exposure of Chardonnay increased sunburning of grapes, and cluster exposure of Pinot Noir at veraison caused a 1% reduction in juice soluble solids concentration at harvest. The detrimental effects of cluster exposure by basal leaf removal at veraison, as well as the lack of any major effect on the acid content of the berries, suggest that the practice has no value for acid reduction during a warm, dry maturation season in western Oregon. 2. A rapid, simple procedure for the estimation of the malate and tartrate content of grape juice is described. The procedure, which requires only a pH meter for instrumentation, does not directly measure malate and tartrate but instead measures their buffering effect. Samples are titrated between pH 2.70-3.00 and pH 4.50-4.80 and the titrant volumes required are compared to two sets of empirically derived standard curves. The malate and tartrate composition of the sample may be determined by a graphical or algebraic method. The use of the estimation method, its advantages, and its limitations are illustrated with different viticultural trials. The estimation error (estimated value - measured value) was influenced by many factors including maturity, season, vineyard location, and cultivar. Standard deviations of the estimation error for malate and tartrate in mature grapes were equal to 9% and 15%, respectively, of the mean malate and tartrate concentrations in pooled Pinot Noir and Chardonnay samples from different vineyards and years. The estimation error is probably due to interference from other buffers present in juice. Although not as accurate as existing analytical methods, the estimation method appears potentially useful for determining relative effects of treatments in vineyard trials where analytical equipment is unavailable or for monitoring malate decline during maturation of grapes. / Graduation date: 1987
139

A critical appraisal of the inter-relationship of the tourism industry and the wine industry: An analysis of wine tourism on the Granite Belt area in Queensland, Australia

Thomas, Catherine M. Unknown Date (has links)
No description available.
140

A critical appraisal of the inter-relationship of the tourism industry and the wine industry: An analysis of wine tourism on the Granite Belt area in Queensland, Australia

Thomas, Catherine M. Unknown Date (has links)
No description available.

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