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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.
11

Agricultura e Meio Ambiente: percepções e práticas de sojicultores em Rio Verde-GO / Agriculture and environment: perceptions and practices of soybean-planters in Rio Verde-GO.

Barreto, Clarissa de Araújo 20 April 2007 (has links)
A agricultura foi responsável por transformar os modos de vida há milhares de anos atrás. Mais recentemente, a transformação desencadeada pela agricultura ocorreu através da modernização de seus processos produtivos. Em território brasileiro, a modernização agrícola possibilitou amplamente o cultivo de soja. A alta demanda e os bons preços no mercado internacional incitaram a promoção de políticas de incentivo ao cultivo de soja, principalmente no bioma Cerrado. Ademais os benefícios econômicos, a sojicultura realizada nos moldes da modernização agrícola brasileira, com grandes aportes mecânicos e químicos, e manutenção da estrutura fundiária causa impactos ambientais e sociais. Desmatamento, poluição de cursos d’água, erosão, compactação de solos, intoxicação e concentração de terra são alguns desses problemas. No presente trabalho, procurou-se traçar o perfil e verificar as percepções e práticas de um grupo de produtores de soja, isto é, sojicultores, atores sociais envolvidos com o cultivo de soja, em torno de sua atividade produtiva e do meio ambiente. A pesquisa se realizou no município maior produtor de soja de Goiás, Rio Verde, cuja vegetação nativa é típica de Cerrado. Também se procurou verificar a existência e a situação dos problemas ambientais mais percebidos pelo grupo de sojicultores em Rio Verde. Para alcançar tais objetivos, aplicou-se questionário a um grupo de 50 sojicultores em 3 grandes lojas revendedoras de produtos agropecuários de Rio Verde. Posteriormente, os dados foram processados pelo programa computacional EPI INFO e analisados. De forma geral, os questionários revelaram que o grupo pesquisado cultivava soja nos padrões verificados no Cerrado, isto é, em grandes propriedades e intensivo em mecanização e agrotóxicos. Em relação às percepções e às práticas, constatou-se que de uma forma geral, a percepção ambiental dos sojicultores entrevistados não necessariamente influenciava na adoção de práticas agrícolas sustentáveis. A adoção do plantio direto, que apregoa a mitigação de impactos da agricultura no ambiente, é sinal de uma agricultura mais sustentável, apesar da exigência de maiores quantidades de herbicidas. Desmatamento, poluição das águas, erosão e intoxicação foram os problemas ambientais mais percebidos pelos entrevistados. A verificação da existência e situação desses problemas ocorreu através de mapas de uso do solo de Rio Verde dos anos 1975, 1989 e 2005, dos autos de infração emitidos por órgãos de fiscalização ambiental, dos resultados das análises de resíduos de agrotóxicos na água destinada ao abastecimento público do município e dos casos de intoxicação por agrotóxico de uso agrícola no município. Por falta de dados não foi possível conferir a presença de erosão. A presença e gravidade do desmatamento, que ocorreu entre 1975 e 2005, puderam ser detectadas pelos dados analisados. Já os dados sobre intoxicação, por possivelmente estarem subnotificados, revelaram um problema de saúde pública. Concluiu-se a necessidade de ações pelo poder público para que haja uma verdadeira fiscalização ambiental em Rio Verde, a tomada de medidas que melhorem a notificação de casos de intoxicação, e a promoção de incentivos àqueles agricultores que respeitam as leis ambientais. Também se faz necessário o desenvolvimento de técnicas agrícolas mais sustentáveis dos pontos de vista econômico, produtivo, social e ambiental. / Agriculture was responsible for transforming the ways of life millions of years ago. More recently, the transformation promoted by agriculture happened through the modernization of its productive processes. In Brazilian territory, the agricultural modernization made possible soybean growing. The strong demand and the good prices at the international market motivated incentive policies for soybean growing, mainly at the Cerrado biome. Besides the economic benefits, soybean growing conducted through Brazilian agriculture modernization, with huge mechanical and chemical inputs, and the maintenance of the land distribution structure caused environmental and social impacts. Deforestation, pollution of waters, soil erosion and depletion, intoxication and land concentration are some of these problems. In the present work, the aim was to outline the profile and verify the perceptions and practices of a group of soybean-planters, social actors involved with the growing of soybean, along its productive activity and the environment. The research was done at the largest soybean grower municipality of Goiás, Rio Verde, with native vegetation typical of Cerrado. It also aimed to verify the existence and the situation of the most perceived environmental problems by the group of soybean-planters in Rio Verde. To reach those objectives, a questionnaire was applied to a group of 50 soybean-planters at 3 big agricultural products reselling stores of Rio Verde. Data obtained was processed by EPI INFO computer program and analyzed. Broadly speaking, the questionnaire revealed that the investigated group grew soybean into the Cerrado patterns, which means, on large properties with intensive use of mechanization and pesticides. About the perceptions and practices, it was verified that, broadly speaking, the environmental perception of the interviewed soybean-planters not necessarily influenced the adoption of sustainable agricultural practices. The no-till system adoption, that reduces agricultural impacts on the environment, is a signal of a more sustainable agriculture, although it demands greater amounts of herbicides. Deforestation, water pollution, soil erosion and intoxication were the most perceived environmental problems by the interviewees. The verification of the existence and situation of these problems was done through maps of Rio Verde’s land use of the years 1975, 1989 and 2005; by illegal deforestation infractions issued by environmental control offices, by the results of pesticides remains analyses in the drinking water of the city, and by the intoxication cases by pesticides of agricultural use at the municipality. Soil erosion couldn’t be checked due to lack of data. The deforestation presence, that took place between 1975 e 2005, and its seriousness, could be detected by the analyzed data. The intoxication data, that were probably under notified, revealed a public health problem. As conclusion it was emphasized the need of public actions in order to promote a better environmental control in Rio Verde, the adoption of measures that would improve the notification of intoxication cases, and the promotion of incentives for those planters that respect the environmental laws. It is also necessary to devise more sustainable agricultural techniques according to the economic, productive, social and environmental points of view.
12

Agricultura e Meio Ambiente: percepções e práticas de sojicultores em Rio Verde-GO / Agriculture and environment: perceptions and practices of soybean-planters in Rio Verde-GO.

Clarissa de Araújo Barreto 20 April 2007 (has links)
A agricultura foi responsável por transformar os modos de vida há milhares de anos atrás. Mais recentemente, a transformação desencadeada pela agricultura ocorreu através da modernização de seus processos produtivos. Em território brasileiro, a modernização agrícola possibilitou amplamente o cultivo de soja. A alta demanda e os bons preços no mercado internacional incitaram a promoção de políticas de incentivo ao cultivo de soja, principalmente no bioma Cerrado. Ademais os benefícios econômicos, a sojicultura realizada nos moldes da modernização agrícola brasileira, com grandes aportes mecânicos e químicos, e manutenção da estrutura fundiária causa impactos ambientais e sociais. Desmatamento, poluição de cursos d’água, erosão, compactação de solos, intoxicação e concentração de terra são alguns desses problemas. No presente trabalho, procurou-se traçar o perfil e verificar as percepções e práticas de um grupo de produtores de soja, isto é, sojicultores, atores sociais envolvidos com o cultivo de soja, em torno de sua atividade produtiva e do meio ambiente. A pesquisa se realizou no município maior produtor de soja de Goiás, Rio Verde, cuja vegetação nativa é típica de Cerrado. Também se procurou verificar a existência e a situação dos problemas ambientais mais percebidos pelo grupo de sojicultores em Rio Verde. Para alcançar tais objetivos, aplicou-se questionário a um grupo de 50 sojicultores em 3 grandes lojas revendedoras de produtos agropecuários de Rio Verde. Posteriormente, os dados foram processados pelo programa computacional EPI INFO e analisados. De forma geral, os questionários revelaram que o grupo pesquisado cultivava soja nos padrões verificados no Cerrado, isto é, em grandes propriedades e intensivo em mecanização e agrotóxicos. Em relação às percepções e às práticas, constatou-se que de uma forma geral, a percepção ambiental dos sojicultores entrevistados não necessariamente influenciava na adoção de práticas agrícolas sustentáveis. A adoção do plantio direto, que apregoa a mitigação de impactos da agricultura no ambiente, é sinal de uma agricultura mais sustentável, apesar da exigência de maiores quantidades de herbicidas. Desmatamento, poluição das águas, erosão e intoxicação foram os problemas ambientais mais percebidos pelos entrevistados. A verificação da existência e situação desses problemas ocorreu através de mapas de uso do solo de Rio Verde dos anos 1975, 1989 e 2005, dos autos de infração emitidos por órgãos de fiscalização ambiental, dos resultados das análises de resíduos de agrotóxicos na água destinada ao abastecimento público do município e dos casos de intoxicação por agrotóxico de uso agrícola no município. Por falta de dados não foi possível conferir a presença de erosão. A presença e gravidade do desmatamento, que ocorreu entre 1975 e 2005, puderam ser detectadas pelos dados analisados. Já os dados sobre intoxicação, por possivelmente estarem subnotificados, revelaram um problema de saúde pública. Concluiu-se a necessidade de ações pelo poder público para que haja uma verdadeira fiscalização ambiental em Rio Verde, a tomada de medidas que melhorem a notificação de casos de intoxicação, e a promoção de incentivos àqueles agricultores que respeitam as leis ambientais. Também se faz necessário o desenvolvimento de técnicas agrícolas mais sustentáveis dos pontos de vista econômico, produtivo, social e ambiental. / Agriculture was responsible for transforming the ways of life millions of years ago. More recently, the transformation promoted by agriculture happened through the modernization of its productive processes. In Brazilian territory, the agricultural modernization made possible soybean growing. The strong demand and the good prices at the international market motivated incentive policies for soybean growing, mainly at the Cerrado biome. Besides the economic benefits, soybean growing conducted through Brazilian agriculture modernization, with huge mechanical and chemical inputs, and the maintenance of the land distribution structure caused environmental and social impacts. Deforestation, pollution of waters, soil erosion and depletion, intoxication and land concentration are some of these problems. In the present work, the aim was to outline the profile and verify the perceptions and practices of a group of soybean-planters, social actors involved with the growing of soybean, along its productive activity and the environment. The research was done at the largest soybean grower municipality of Goiás, Rio Verde, with native vegetation typical of Cerrado. It also aimed to verify the existence and the situation of the most perceived environmental problems by the group of soybean-planters in Rio Verde. To reach those objectives, a questionnaire was applied to a group of 50 soybean-planters at 3 big agricultural products reselling stores of Rio Verde. Data obtained was processed by EPI INFO computer program and analyzed. Broadly speaking, the questionnaire revealed that the investigated group grew soybean into the Cerrado patterns, which means, on large properties with intensive use of mechanization and pesticides. About the perceptions and practices, it was verified that, broadly speaking, the environmental perception of the interviewed soybean-planters not necessarily influenced the adoption of sustainable agricultural practices. The no-till system adoption, that reduces agricultural impacts on the environment, is a signal of a more sustainable agriculture, although it demands greater amounts of herbicides. Deforestation, water pollution, soil erosion and intoxication were the most perceived environmental problems by the interviewees. The verification of the existence and situation of these problems was done through maps of Rio Verde’s land use of the years 1975, 1989 and 2005; by illegal deforestation infractions issued by environmental control offices, by the results of pesticides remains analyses in the drinking water of the city, and by the intoxication cases by pesticides of agricultural use at the municipality. Soil erosion couldn’t be checked due to lack of data. The deforestation presence, that took place between 1975 e 2005, and its seriousness, could be detected by the analyzed data. The intoxication data, that were probably under notified, revealed a public health problem. As conclusion it was emphasized the need of public actions in order to promote a better environmental control in Rio Verde, the adoption of measures that would improve the notification of intoxication cases, and the promotion of incentives for those planters that respect the environmental laws. It is also necessary to devise more sustainable agricultural techniques according to the economic, productive, social and environmental points of view.
13

Utveckling av fröutmatningsenhet till såmaskiner : Med fokus på jämn fördelning och kontrollerad utmatningshastighet / Development of Seed Dispensing Unit for Seed Drills : With Focus on Uniform Distribution and Controlled Dispensing Velocity

Ohlén, Kajsa, Eriksson, Oscar January 2024 (has links)
This master thesis was conducted during the spring of 2024 at Väderstad AB. Väderstad manufactures agricultural machines, including two types of seed drills used to plant seeds: conventional seed drills and precision planters. The primary difference lies in the seed dispensing unit, which distributes the seeds from storage before planting. Conventional seed drills utilize randomness to distribute seeds, while precision planters use a complex unit that dispenses seeds one by one. The precision seed dispensing unit comes at a higher cost and requires more space, resulting in wider row spacing compared to conventionalseed drills. A low row distance is desired to maximize crop yield. This master thesis aims to develop a seed dispensing unit which can be used for a new type of seed drill. The seed dispensing unit intends to be smaller and less costly than the ones for precision planters, while achieving a better seed distribution than the conventional seed drills. The product development was carried out through a tailored process for this project, incorporating methods such as Blackbox, Brainwriting, and Pugh’s concept selection matrix. The process generated three concepts which were modeled in CAD and printed using a 3D printer. The models underwent functional assessment and seeding capacity testing, followed by redesign, reprinting, and testing in an iterative process. The master thesis resulted in two concepts which were presented for Väderstad. The first prototype consisted of a wheel with indentations. As the wheel rotated, the indentations picked up seeds and then released them into an airflow-assisted seed transport which sent the seeds into the ground. The second prototype featured a vertical screw that rotated upwards, distributing seeds evenly against the wall. This prototype also used an airflow-assisted seed transport. Presently, Väderstad has submitted a patent application for the screw concept and will continue its development within the company. / Detta examensarbete utfördes under våren 2024 hos Väderstad AB. På Väderstadtillverkas två typer av såmaskiner som används till fröplantering: konventionella såmaskiner samt precisionssåmaskiner. Den primära skillnaden mellan såmaskinerna är fröutmatningsenheten som används till fördelning av utsäde från sålådan innan plantering. I konventionella såmaskiner används slumpen till fördelningen, medan i precisionssåmaskiner används en komplex enhet där fröna matas ut ett i taget. Precisionssåmaskinens fröutmatningsenhet är dyrare samt större. Dess storlek begränsar avståndet mellan raderna där fröna planteras. Således blir radavståndet för precisionssåmaskinen större än för konventionella såmaskinen. Egentligen eftersträvas låga radavstånd för maximal avkastning på skörden. Examensarbetet syftades till att utveckla en fröutmatningsenhet som kan användas i en ny typ av såmaskin. Fröutmatningsenheten ämnades att vara mindre och billigare än den i precisionssåmaskinen, samtidigt som den uppnår en bättre fröfördelning än den konventionella såmaskinen. Produktutvecklingsmetoden anpassades efter projektet, den använde metoder som Blackbox, Brainwriting och Pughs konceptvalsmatris. Processen genererade tre koncept som modellerades i CAD och skrevs ut med en 3D-skrivare. Modellerna genomgick funktionellbedömning och testning av utmatningskapacitet, följt av omkonstruktion, ny 3D-utskrift och testning i en iterativ process. Utifrån produktutvecklingsprocessen genererades två koncept med prototyper. Den förstaprototypen bestod av ett hjul med fack. När hjulet roteras förbi fröbehållaren fångasutsädet i facken. Därefter släpps utsädet i en luftassisterad frötransport som transporterardet till marken. Den andra prototypen bestod av vertikal skruv som drivs uppåt. Utsädettrycks då ut mot skruvens vägg vilket gör att det fördelas jämnt. När fröna matas ut ur skruven plockas de upp av en luftassisterad frötransport som för dem till marken. Idag har Väderstad patentansökt den sistnämnda idéen och kommer fortsätta utveckla den inomföretaget.
14

Masters No More: Abolition and Texas Planters, 1860-1890

Ivan, Adrien D. 12 1900 (has links)
This dissertation is a study of the effects of the abolition of slavery on the economic and political elite of six Texas counties between 1860 and 1890. It focuses on Austin, Brazoria, Colorado, Fort Bend, Matagorda, and Wharton Counties. These areas contain the overwhelming majority of Stephen F. Austin's "Old Three Hundred," the original American settlers of Texas. In addition to being the oldest settled region, these counties contained many of the wealthiest slaveholders within the state. This section of the state, along with the northeast along the Louisiana border, includes the highest concentration of Texas' antebellum plantations. This study asks two central questions. First, what were the effects of abolition on the fortunes of the planter class within these six counties? Did a new elite emerge as a result of the end of slavery, or, despite the liquidation of a substantial portion of their estates, did members of the former planter class sustain their economic dominance over the counties? Second, what were abolition's effects on the counties' prewar political elite, defined as the county judge? Who were in power before the war and who were in power after it? Did abolition contribute to a new kind of politician?
15

Les plantations d'hévéa en Cochinchine (1897-1940) / The rubber plantations in Cochinchina (1897-1940)

Tran, Xuan Tri 19 January 2018 (has links)
Dès la conquête de la Cochinchine en 1862, l’Administration coloniale et des particuliers français exploitèrent l’agriculture locale et y développèrent l’économie. Ils tentèrent de faire l’essai et d’introduire diverses cultures, en particulier des arbres à caoutchouc. L’année 1897 marqua le début de l’hévéaculture de Cochinchine, lorsqu’on planta avec succès près de deux mille hévéas brasiliensis. La superficie de l’hévéaculture en Cochinchine se développait prodigieusement, allant de cent hectares à la fin du XIXème siècle à près de cent mille hectares au début des années trente, grâce d’une part à des capitaux provenant de la Métropole et, d’autre part à des mesures d’encouragement du Gouvernement colonial. Les plantations d’hévéa attirèrent les travailleurs locaux, surtout en provenance du Tonkin et de l’Annam, à raison d’une dizaine de mille, parfois une vingtaine de mille par an.Parallèlement à l’extension des superficies plantées, la production du caoutchouc de la colonie s’accrut rapidement, allant d’un peu plus d’une tonne en 1908 à plus de soixante mille tonnes en 1939. Les plantations d’hévéa devinrent l’une des cultures les plus importantes de Cochinchine à l’époque coloniale française. Non seulement elles apportèrent la fortune aux planteurs de la colonie, mais elles assurèrent une partie, et depuis 1938, la totalité des besoins de caoutchouc de l’industrie métropolitaine. Les plantations d’hévéa de Cochinchine représentaient un symbole de la colonisation agricole française, mais aussi hélas l’une des pages noires de l’histoire du colonialisme français au Vietnam par l’exploitation brutale des planteurs envers les travailleurs vietnamiens. / As early as the conquest of Cochinchina in 1862, the colonial administration and French individuals exploited the local agriculture and developed the economy there. They tried to experiment and introduce various crops, especially rubber trees. The year of 1897 marked the beginning of the rubber plantation of Cochinchina, when two thousand rubber trees brasiliensis were successfully planted. The area of rubber tree plantation in Cochinchina grew tremendously, ranging from one hundred hectares at the end of the 19th century to nearly one hundred thousand hectares in the early 1930s, because of, on the one hand, the capital invested from the metropolis, and, on the other hand, the measures of encouragement taken by the colonial Government. The rubber plantations attracted local workers, mainly from Tonkin and Annam, at a rate of about 10.000, sometimes 20.000 persons a year. In parallel with the extension of the area of rubber plantation, the colonial rubber production rapidly increased from just over one tonne in 1908 to more than 60.000 tons in 1939.The rubber tree plantation became one of the most important crops of Cochinchina during the French colonial era. Not only they brought fortune to the planters of the colony, but they secured a part, and since 1938, the whole of the rubber demands of the metropolitan industries. The Cochinchina rubber plantations represented a symbol of French agricultural colonization and, unfortunately, one of the black pages of the history of French colonialism in Vietnam by the brutal exploitation of Vietnamese workers by rubber planters.
16

Vertical gardening in a northern city; speculations for Winnipeg

Urben-Imbeault, Tamara 26 May 2015 (has links)
This practicum is a reference for vertical gardeners in cold climates. Winnipeg, Manitoba is explored, however findings may be applied to other cities in similar climates. First, the history of vertical gardening is discussed, then the types of vertical gardens currently on the market are described. These can be classified into two categories: soil bearing or non-soil bearing. Most designs are modular pre-planted systems that can be attached to any wall, as long as it satisfies the structural requirements recommended by the manufacturer. The benefits of vertical gardening have been shown to be rather extensive, covering a wide range of areas. Aesthetic improvement, reduction of the Urban Heat Island (UHI) effect, improvement of air quality, stormwater absorption, noise reduction, native habitat integration, reduction of heating and cooling costs for buildings, food production, marketing, and biophilia are all benefits explored in detail. Difficulties associated with vertical gardening are discussed, specifically the lack of knowledge and awareness of vertical gardens, lack of empirical evidence (or missing details in existing research), overall cost and lack of financial incentives, lack of industry codes, and various associated risks. Design framework exists within microclimate conditions unique to vertical gardens, as well as neighbourhood and regional (micro)climates. Theories relating to the study of green walls covered include the human ecosystem model, urban reconciliation ecology, habitat templating, the urban cliff hypothesis, and wall ecology. Suitable habitat templates identified for vertical gardens in Winnipeg are cliffs, sand dunes, alvars, mixed grass prairie and prairie potholes. Design parameters to be followed for vertical garden design in Winnipeg are to ensure that lightweight materials are used, to provide insulation to protect plants from sudden temperature changes, to choose plants that grow in the region and are adapted to grow in areas with limited soil, increased wind, varying degrees of sunlight (depending on orientation), and increased pollution and salt spray depending on location. / October 2015

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