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<p>Previous studies of agricultural conditions in the Mekong Delta (MD) have identified soil compaction as an obstacle to sustainable production. A conceptual model for soil formation was presented to demonstrate the link between soil hydrology and plant response. Detailed studies of soil moisture dynamics in agricultural fields were conducted using a dynamic process-orientated model. Pressure head and water flow were simulated for three selected sites during a year for which empirical data were available. Daily meteorological data were used as dynamic input and measured pressure head was used to estimate parameter values that satisfied various acceptance criteria. The Generalised Likelihood Uncertainty Estimation (GLUE) approach was applied for calibration procedures with 10,000 runs, each run using random values within the chosen range of parameter values. To evaluate model performance and uncertainty estimation, re-sampling was carried out using coefficient of determination (R2) and mean error (ME) as the criteria. Correlations between parameters and R2 (and ME) and among parameters were also considered to analyse the relationship of the selected parameter set in response to increases/decreases in the acceptable simulations. The method was successful for two of the three sites, with many accepted simulations. For these sites, the uncertainty was reduced and it was possible to quantify the importance of the different parameters.</p><p> </p>

Orientador: Luiz Carlos Pavani / Banca: Fernando Braz Tangerino Hernandez / Banca: Jarbas Honorio de Miranda / Banca: José Eduardo Corá / Banca: Leandro Borges Lemos / Resumo: cultura do feijoeiro apresenta relevada importância no contexto agrícola nacional, sendo cultivado em três épocas do ano, com a de inverno apresentando as maiores produtividades. O objetivo deste trabalho foi avaliar dois métodos de manejo de irrigação, um por tensiometria (Tens) e outro pelo tanque Classe A (TCA), em uma área irrigada com pivô central conjugados com os sistemas plantio direto (PD) e convencional (PC) de manejo do solo, em Jaboticabal-SP, com a cultura do feijoeiro. O delineamento experimental utilizado foi semelhante aos blocos casualizados, em um esquema fatorial 2x2. Foram avaliados o índice de área foliar (IAF), número de vagens por planta, número de grãos por vagem, massa de 1000 grãos e produtividade de grãos, massa seca e número de folha, caule, flor e vagem, variação da umidade do solo e evapotranspiração real (ETr) estimada pelo método do balanço hídrico do solo. Conclui-se que: para número de grãos por vagem, vagens produtivas por planta, massa de 1000 grãos e produtividade, os melhores resultados foram encontrados para as combinações PC-TCA e PD-Tens; o manejo de irrigação TCA proporcionou maior lâmina total de irrigação, maior umidade do solo e maior ETr; não houve diferença entre sistemas de manejo do solo para lâmina de irrigação aplicada; os dois manejos de irrigação aplicados (Tens e TCA) se mostraram bons métodos para o manejo da irrigação na cultura do feijoeiro. / Abstract: The dry bean crop presents raised importance in the national agricultural context, being cultivated at three times of the year, being that of winter it comes presenting the biggest yield. The objective of this study was to compare two methods of management irrigation under center pivot, one by soil (tensiometry) and another by climate (Class A pan), in conventional and no-tillage systems, on the dry bean crop. A similar randomized blocks design, with a 2x2 factorial arrangement was applied. They were evaluated the leaf area index (IAF), average number of leaves, pods, grains per pods; weight of 1000 grains and grain yield; dry mass production of the leaves, stems, flowers and pods; variation of the soil moisture and real evapotranspiration (ETr) estimated by soil water balance method. It concluded, for the average of two years analyzed: for grains number per pod, yield pods for plant, weight of 1000 grains and grains yield, the best ones results had been found for the combinations conventional tillage and Class A pan and no-tillage and tensiometry systems combinations; the irrigation management Class A pan resulted in bigger irrigation water, soil water storage and ETr; it did not have difference between systems tillage for irrigation water; the two applied irrigation management (tensiometry and Class A pan) had shown good methods for the irrigation management in dry bean crop. / Doutor

The purpose of this thesis was to compare the tensiometer and climatic methods of scheduling irrigation of potatoes under field conditions. Tensiometers were placed in a 160 acre field to maintain the crop within the optimum moisture range and schedule irrigations. An automatic solid set system was used to apply water to the potato crop. Instrumentation was used to determine daily input for the climatological method. Daily evapotranspiration (Et) was computed and Et (tensiometer) was comPared with Et (climatic). The results showed total variation of the climatic method from the tensiometer method of .62 inches or less than 5 per cent. The study indicated that the climatological method would have under irrigated the potato crop by . 62 inches during the 48 day study. Variations are also shown for each irrigation interval. Results indicated that a combination of both methods would allow the most feasible approach to scheduling irrigation of potatoes.

Made available in DSpace on 2014-06-11T19:33:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-12-15Bitstream added on 2014-06-13T20:25:28Z : No. of bitstreams: 1 lopes_as_dr_jabo.pdf: 1251715 bytes, checksum: 78fd2a64f53f96716f9234e9a9874854 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / cultura do feijoeiro apresenta relevada importância no contexto agrícola nacional, sendo cultivado em três épocas do ano, com a de inverno apresentando as maiores produtividades. O objetivo deste trabalho foi avaliar dois métodos de manejo de irrigação, um por tensiometria (Tens) e outro pelo tanque Classe A (TCA), em uma área irrigada com pivô central conjugados com os sistemas plantio direto (PD) e convencional (PC) de manejo do solo, em Jaboticabal-SP, com a cultura do feijoeiro. O delineamento experimental utilizado foi semelhante aos blocos casualizados, em um esquema fatorial 2x2. Foram avaliados o índice de área foliar (IAF), número de vagens por planta, número de grãos por vagem, massa de 1000 grãos e produtividade de grãos, massa seca e número de folha, caule, flor e vagem, variação da umidade do solo e evapotranspiração real (ETr) estimada pelo método do balanço hídrico do solo. Conclui-se que: para número de grãos por vagem, vagens produtivas por planta, massa de 1000 grãos e produtividade, os melhores resultados foram encontrados para as combinações PC-TCA e PD-Tens; o manejo de irrigação TCA proporcionou maior lâmina total de irrigação, maior umidade do solo e maior ETr; não houve diferença entre sistemas de manejo do solo para lâmina de irrigação aplicada; os dois manejos de irrigação aplicados (Tens e TCA) se mostraram bons métodos para o manejo da irrigação na cultura do feijoeiro. / The dry bean crop presents raised importance in the national agricultural context, being cultivated at three times of the year, being that of winter it comes presenting the biggest yield. The objective of this study was to compare two methods of management irrigation under center pivot, one by soil (tensiometry) and another by climate (Class A pan), in conventional and no-tillage systems, on the dry bean crop. A similar randomized blocks design, with a 2x2 factorial arrangement was applied. They were evaluated the leaf area index (IAF), average number of leaves, pods, grains per pods; weight of 1000 grains and grain yield; dry mass production of the leaves, stems, flowers and pods; variation of the soil moisture and real evapotranspiration (ETr) estimated by soil water balance method. It concluded, for the average of two years analyzed: for grains number per pod, yield pods for plant, weight of 1000 grains and grains yield, the best ones results had been found for the combinations conventional tillage and Class A pan and no-tillage and tensiometry systems combinations; the irrigation management Class A pan resulted in bigger irrigation water, soil water storage and ETr; it did not have difference between systems tillage for irrigation water; the two applied irrigation management (tensiometry and Class A pan) had shown good methods for the irrigation management in dry bean crop.

Made available in DSpace on 2014-06-11T19:23:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-05Bitstream added on 2014-06-13T19:47:19Z : No. of bitstreams: 1 gerolineto_e_me_jabo.pdf: 292237 bytes, checksum: 3d56e87cb5af9da13c13b0755e29d5b9 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A grama-esmeralda (Zoysia japonica STEUD) é uma das mais importantes gramas comercializadas no Brasil. O objetivo deste trabalho foi estudar o seu desenvolvimento, sob dois manejos de irrigação: T1 – irrigado quando a leitura do tensiômetro foi igual a–50 kPa, onde uma lâmina de água foi calculada pelo do Método de Penman-Monteith, por dados obtidos em uma estação meteorológica automatizada; T2 – irrigado segundo procedimentos adotados pelo gramicultor (vinte minutos de aspersão em média). O experimento foi conduzido no Sítio Santo Antonio da empresa Green-Park Gramados Ornamentais, em Pitangueiras, SP, de novembro de 2006 a outubro de 2007. As avaliações dos tratamentos foram mensais, sendo coletadas das áreas experimentais amostras em forma de cubo, com 10 centímetros de aresta. Em cada amostra foi avaliada a altura da maior folha, matéria seca aérea e matéria seca radicular. Foi utilizado o delineamento experimental inteiramente casualizado, com dois tratamentos e oito repetições, sendo cada repetição foi representada pela média de quatro amostras. As análises estatísticas demonstraram que o tratamento T1 teve maior desenvolvimento da grama esmeralda em cinco dos doze meses de experimento. / The aim of this work was to study the development of zoysiagrass (Zoysia japonica STEUD) great economic importance in Brazil, under two irrigation levels: T1 treatment: irrigated when reading tensionmeter was –50 kPa and irrigated by the Penman-Monteith method, obtained through meteorological station; and T2 treatment: irrigated according to procedures adopted by the grower of grass (twenty minutes of spraying). The experiment was conducted on Green Park Farm, located in Pitangueiras City, SP, november 2006 to october 2007, in one year. The evaluations were monthly, and collected from areas experimental samples were in the shape of a cube, with 10 cm in length x width x height. It was measured the height of the largest sheet of each sample, then sheet and the roots of each sample were dried in oven for further weighing. The experiment was conducted in a experimental design randomized, in a total of two treatments and eight repetitions. The statistical analyses showed in the T1 treatment the best development of zoysiagrass, in one year.

Made available in DSpace on 2014-06-11T19:24:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-05Bitstream added on 2014-06-13T20:52:29Z : No. of bitstreams: 1 trabulsi_mcm_me_botfca.pdf: 565458 bytes, checksum: c26dff5da232d30b005b2b5b62a46498 (MD5) / O presente trabalho teve como objetivo avaliar as relações hídricas no solo em função de diferentes espaçamentos em uma floresta de curta rotação, assim como o crescimento das árvores de Eucalyptus urograndis. A implantação da floresta ocorreu em dezembro de 2008 e o experimento somente foi instalado em janeiro de 2010. A área total de dois hectares foi subdividida em cinco parcelas com espaçamentos diferentes (2,8 metros entre linhas e 0,5, 1,0, 1,5, 2,0 e 2,5 m entre plantas). Foram feitas análises da umidade do solo semanalmente, através de dois métodos, gravimétrico e dos tensiômetros. Nas cinco parcelas com o plantio de Eucalyptus urograndis foram instaladas, aleatoriamente, três baterias de tensiômetros a duas profundidades, sendo 0,30 e 0,90 metro. Os dados foram coletados de fevereiro de 2010 a janeiro de 2011. Ao começar a época da seca, em julho de 2010, iniciou-se a coleta de amostras de solo pelo método gravimétrico. Foram coletadas três amostras por parcela e por profundidade, totalizando 30 amostras, sendo que o local de coleta foi escolhido aleatoriamente dentro de cada parcela, porém a 0,50 metro da linha de plantio. Os dados do potencial matricial foram obtidos através dos tensiômetros e transformados em umidade por curvas de retenção de água determinadas na área. Os dados pluviométricos foram obtidos através da Estação Agrometeorológica da Faculdade de Ciências Agronômicas, sendo utilizados para elaborar o balanço hídrico da região através do Método de Thornthwaite e Matther. Também foram avaliados aspectos físicos do solo como: densidade de partículas, densidade do solo e porosidade total. Para obter a informação sobre o crescimento das árvores, foram coletados no início e ao final do experimento, dados de altura e diâmetro de 30 árvores... / The aim of this study was to evaluate the soil-water relations in the soil as a function of different spacing in a short rotation forest and evaluate the growth of Eucalyptus urograndis. The forest was planted in December 2008 and this research was installed in January 2010. The two hectares area was subdivided in five plots with different spacing (2.8 x 0.5, 2.8 x 1.0, 2.8 x 1.5, 2.8 x 2.0, 2.8 x 2.5 meters). The moisture soil was analyzed thought two methods, gravimetric and tensiometers. In all the five plots, it was installed three batteries of tensiometers in two different deeps, 0.30 and 0.90 meters. Data was collected from February 2010 to January 2011. When the dry season has begun, in July 2010, the samples started to be collected thought gravimetric method. It was collected three samples by plot and deep, in a total of 30 randomized samples inside the plots, but 0.50 meter from the row. Matric Potential data was obtained thought tensiometers and changed to moisture thought retention curves. Pluviometer data were obtained from Agronomic Sciences Faculty Agrometeorology Station and used to elaborate the water balance of the region thought Thornthwaite Method. Soil physics were evaluated. The growth of the trees was evaluated collecting high and diameter breast high. The spacing 2.8 x 2.5 m has fewer trees, so there’s more water in the soil. And the spacing 2.8 x 0.5 m has more trees, less water in the soil because of the competition between plants

Orientador: José Eduardo Pitelli Turco / Banca: José Renato Zanini / Banca: Roberto Lyra Villas Bôas / Resumo: A grama-esmeralda (Zoysia japonica STEUD) é uma das mais importantes gramas comercializadas no Brasil. O objetivo deste trabalho foi estudar o seu desenvolvimento, sob dois manejos de irrigação: T1 - irrigado quando a leitura do tensiômetro foi igual a-50 kPa, onde uma lâmina de água foi calculada pelo do Método de Penman-Monteith, por dados obtidos em uma estação meteorológica automatizada; T2 - irrigado segundo procedimentos adotados pelo gramicultor (vinte minutos de aspersão em média). O experimento foi conduzido no Sítio Santo Antonio da empresa Green-Park Gramados Ornamentais, em Pitangueiras, SP, de novembro de 2006 a outubro de 2007. As avaliações dos tratamentos foram mensais, sendo coletadas das áreas experimentais amostras em forma de cubo, com 10 centímetros de aresta. Em cada amostra foi avaliada a altura da maior folha, matéria seca aérea e matéria seca radicular. Foi utilizado o delineamento experimental inteiramente casualizado, com dois tratamentos e oito repetições, sendo cada repetição foi representada pela média de quatro amostras. As análises estatísticas demonstraram que o tratamento T1 teve maior desenvolvimento da grama esmeralda em cinco dos doze meses de experimento. / Abstract: The aim of this work was to study the development of zoysiagrass (Zoysia japonica STEUD) great economic importance in Brazil, under two irrigation levels: T1 treatment: irrigated when reading tensionmeter was -50 kPa and irrigated by the Penman-Monteith method, obtained through meteorological station; and T2 treatment: irrigated according to procedures adopted by the grower of grass (twenty minutes of spraying). The experiment was conducted on Green Park Farm, located in Pitangueiras City, SP, november 2006 to october 2007, in one year. The evaluations were monthly, and collected from areas experimental samples were in the shape of a cube, with 10 cm in length x width x height. It was measured the height of the largest sheet of each sample, then sheet and the roots of each sample were dried in oven for further weighing. The experiment was conducted in a experimental design randomized, in a total of two treatments and eight repetitions. The statistical analyses showed in the T1 treatment the best development of zoysiagrass, in one year. / Mestre

Resumo: O presente trabalho teve como objetivo avaliar as relações hídricas no solo em função de diferentes espaçamentos em uma floresta de curta rotação, assim como o crescimento das árvores de Eucalyptus urograndis. A implantação da floresta ocorreu em dezembro de 2008 e o experimento somente foi instalado em janeiro de 2010. A área total de dois hectares foi subdividida em cinco parcelas com espaçamentos diferentes (2,8 metros entre linhas e 0,5, 1,0, 1,5, 2,0 e 2,5 m entre plantas). Foram feitas análises da umidade do solo semanalmente, através de dois métodos, gravimétrico e dos tensiômetros. Nas cinco parcelas com o plantio de Eucalyptus urograndis foram instaladas, aleatoriamente, três baterias de tensiômetros a duas profundidades, sendo 0,30 e 0,90 metro. Os dados foram coletados de fevereiro de 2010 a janeiro de 2011. Ao começar a época da seca, em julho de 2010, iniciou-se a coleta de amostras de solo pelo método gravimétrico. Foram coletadas três amostras por parcela e por profundidade, totalizando 30 amostras, sendo que o local de coleta foi escolhido aleatoriamente dentro de cada parcela, porém a 0,50 metro da linha de plantio. Os dados do potencial matricial foram obtidos através dos tensiômetros e transformados em umidade por curvas de retenção de água determinadas na área. Os dados pluviométricos foram obtidos através da Estação Agrometeorológica da Faculdade de Ciências Agronômicas, sendo utilizados para elaborar o balanço hídrico da região através do Método de Thornthwaite e Matther. Também foram avaliados aspectos físicos do solo como: densidade de partículas, densidade do solo e porosidade total. Para obter a informação sobre o crescimento das árvores, foram coletados no início e ao final do experimento, dados de altura e diâmetro de 30 árvores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the soil-water relations in the soil as a function of different spacing in a short rotation forest and evaluate the growth of Eucalyptus urograndis. The forest was planted in December 2008 and this research was installed in January 2010. The two hectares area was subdivided in five plots with different spacing (2.8 x 0.5, 2.8 x 1.0, 2.8 x 1.5, 2.8 x 2.0, 2.8 x 2.5 meters). The moisture soil was analyzed thought two methods, gravimetric and tensiometers. In all the five plots, it was installed three batteries of tensiometers in two different deeps, 0.30 and 0.90 meters. Data was collected from February 2010 to January 2011. When the dry season has begun, in July 2010, the samples started to be collected thought gravimetric method. It was collected three samples by plot and deep, in a total of 30 randomized samples inside the plots, but 0.50 meter from the row. Matric Potential data was obtained thought tensiometers and changed to moisture thought retention curves. Pluviometer data were obtained from Agronomic Sciences Faculty Agrometeorology Station and used to elaborate the water balance of the region thought Thornthwaite Method. Soil physics were evaluated. The growth of the trees was evaluated collecting high and diameter breast high. The spacing 2.8 x 2.5 m has fewer trees, so there's more water in the soil. And the spacing 2.8 x 0.5 m has more trees, less water in the soil because of the competition between plants / Orientador: Saulo Philipe Sebastião Guerra / Coorientador: João Carlos Cury Saad / Banca: José Mauro Santana da Silva / Banca: Kelly Cristina Tonello / Mestre

Previous studies of agricultural conditions in the Mekong Delta (MD) have identified soil compaction as an obstacle to sustainable production. A conceptual model for soil formation was presented to demonstrate the link between soil hydrology and plant response. Detailed studies of soil moisture dynamics in agricultural fields were conducted using a dynamic process-orientated model. Pressure head and water flow were simulated for three selected sites during a year for which empirical data were available. Daily meteorological data were used as dynamic input and measured pressure head was used to estimate parameter values that satisfied various acceptance criteria. The Generalised Likelihood Uncertainty Estimation (GLUE) approach was applied for calibration procedures with 10,000 runs, each run using random values within the chosen range of parameter values. To evaluate model performance and uncertainty estimation, re-sampling was carried out using coefficient of determination (R2) and mean error (ME) as the criteria. Correlations between parameters and R2 (and ME) and among parameters were also considered to analyse the relationship of the selected parameter set in response to increases/decreases in the acceptable simulations. The method was successful for two of the three sites, with many accepted simulations. For these sites, the uncertainty was reduced and it was possible to quantify the importance of the different parameters.