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A água enquanto matéria construtora da paisagem Texto completo
2009
Alfaiate, T.A. | Quintino, Maria | Ribeiro, Luís | Mendes, Maria Paula | Moura, Carla
info:eu-repo/semantics/publishedVersion
Mostrar más [+] Menos [-]Estimating water application efficiency for drip irrigation emitter patterns on banana Estimativa da eficiência de aplicação de água em bananeira com diferentes sistemas de gotejamento Texto completo
2009
Alisson Jadavi Pereira da Silva | Eugênio Ferreira Coelho | Jarbas Honorio de Miranda | Stephen Ray Workman
Estimating water application efficiency for drip irrigation emitter patterns on banana Estimativa da eficiência de aplicação de água em bananeira com diferentes sistemas de gotejamento Texto completo
2009
Alisson Jadavi Pereira da Silva | Eugênio Ferreira Coelho | Jarbas Honorio de Miranda | Stephen Ray Workman
The objective of this work was to evaluate root and water distribution in irrigated banana (Musa sp.), in order to determine the water application efficiency for different drip irrigation emitter patterns. Three drip emitter patterns were studied: two 4-L h-1 emitters per plant (T1), four 4-L h-1 emitters per plant (T2), and five 4-L h-1 emitters per plant (T3). The emitters were placed in a lateral line. In the treatment T3, the emitters formed a continuous strip. The cultivated area used was planted with banana cultivar BRS Tropical, with a 3-m spacing between rows and a 2.5-m spacing between plants. Soil moisture and root length data were collected during the first production cycle at five radial distances and depths, in a 0.20x0.20 m vertical grid. The experiment was carried out in a sandy clay loam Xanthic Hapludox. Soil moisture data were collected every 10 min for a period of five days using TDR probes. Water application efficiency was of 83, 88 and 92% for the systems with two, four and five emitters per plant, respectively. It was verified that an increase in the number of emitters in the lateral line promoted better root distribution, higher water extraction, and less deep percolation losses.<br>O objetivo deste trabalho foi avaliar a distribuição de água e raízes de bananeira (Musa sp.) irrigada, para determinar a eficiência de aplicação de água por diferentes sistemas de irrigação por gotejamento. Foram estudados três sistemas de gotejamento: T1, dois emissores de 4 L h-1 por planta; T2, quatro emissores de 4 L h-1 por planta; e T3, cinco emissores de 4 L h-1 por planta. Os emissores foram dispostos em uma linha lateral. No tratamento T3, os emissores formaram uma faixa contínua. A área de cultivo foi plantada com bananeira cultivar BRS Tropical com espaçamento de 3 m entre fileiras e de 2,5 m entre plantas. Dados de umidade e comprimento de raízes foram coletados durante o primeiro ciclo da cultura, em cinco distâncias radiais e profundidades, em uma malha vertical de 0,20x0,20 m. O solo da área experimental era um Latossolo Amarelo franco-argilo-arenoso. Os dados de umidade foram coletados em intervalos de 10 min por um período de cinco dias com uso de sondas de TDR. A eficiência de aplicação de água foi de 83, 88 e 92% para os sistemas com dois, quatro e cinco emissores por planta, respectivamente. O incremento no número de emissores na linha lateral promove melhor distribuição radicular, maior extração de água e menores perdas por percolação profunda.
Mostrar más [+] Menos [-]Estimating water application efficiency for drip irrigation emitter patterns on banana Texto completo
2009
Silva, Alisson Jadavi Pereira da(Universidade de São Paulo Escola Superior de Agricultura Luiz de Queiroz Departamento de Engenharia Agrícola) | Coelho, Eugênio Ferreira(Embrapa Mandioca e Fruticultura Tropical) | Miranda, Jarbas Honorio de(USP Esalq Departamento de Ciências Exatas) | Workman, Stephen Ray(Biosystems and Agricultural Engineering Department of Biosystems and Agricultural Engineering)
The objective of this work was to evaluate root and water distribution in irrigated banana (Musa sp.), in order to determine the water application efficiency for different drip irrigation emitter patterns. Three drip emitter patterns were studied: two 4-L h-1 emitters per plant (T1), four 4-L h-1 emitters per plant (T2), and five 4-L h-1 emitters per plant (T3). The emitters were placed in a lateral line. In the treatment T3, the emitters formed a continuous strip. The cultivated area used was planted with banana cultivar BRS Tropical, with a 3-m spacing between rows and a 2.5-m spacing between plants. Soil moisture and root length data were collected during the first production cycle at five radial distances and depths, in a 0.20x0.20 m vertical grid. The experiment was carried out in a sandy clay loam Xanthic Hapludox. Soil moisture data were collected every 10 min for a period of five days using TDR probes. Water application efficiency was of 83, 88 and 92% for the systems with two, four and five emitters per plant, respectively. It was verified that an increase in the number of emitters in the lateral line promoted better root distribution, higher water extraction, and less deep percolation losses. | O objetivo deste trabalho foi avaliar a distribuição de água e raízes de bananeira (Musa sp.) irrigada, para determinar a eficiência de aplicação de água por diferentes sistemas de irrigação por gotejamento. Foram estudados três sistemas de gotejamento: T1, dois emissores de 4 L h-1 por planta; T2, quatro emissores de 4 L h-1 por planta; e T3, cinco emissores de 4 L h-1 por planta. Os emissores foram dispostos em uma linha lateral. No tratamento T3, os emissores formaram uma faixa contínua. A área de cultivo foi plantada com bananeira cultivar BRS Tropical com espaçamento de 3 m entre fileiras e de 2,5 m entre plantas. Dados de umidade e comprimento de raízes foram coletados durante o primeiro ciclo da cultura, em cinco distâncias radiais e profundidades, em uma malha vertical de 0,20x0,20 m. O solo da área experimental era um Latossolo Amarelo franco-argilo-arenoso. Os dados de umidade foram coletados em intervalos de 10 min por um período de cinco dias com uso de sondas de TDR. A eficiência de aplicação de água foi de 83, 88 e 92% para os sistemas com dois, quatro e cinco emissores por planta, respectivamente. O incremento no número de emissores na linha lateral promove melhor distribuição radicular, maior extração de água e menores perdas por percolação profunda.
Mostrar más [+] Menos [-]Effect of mercury on celular transport of water in plants. A review | Efecto de mercurio sobre el transporte celular del agua en plantas. Una revisión Texto completo
2009
Cárdenas Hernández, J.F. | Moreno F., L.P. | Magnitskiy, S.V.
Los metales pesados (MP) pueden afectar las relaciones hídricas de la planta de muchas formas. El Hg inhibe la actividad de las acuaporinas, proteínas que forman los canales transportadores de agua, y de esta manera afecta la conductividad a nivel celular y de tejidos en zonas específicas de la raíz, así como el volumen de las células guarda modificando los movimientos estomáticos. Además, junto con otros metales pesados, el Hg produce cambios morfológicos como el acortamiento o modificación en la elasticidad de las raíces, disminuyendo el área efectiva para la toma de agua. En hojas, el cambio en el número de estomas y de tricomas causado por el Hg, altera la tasa de transpiración. En este artículo se revisa el efecto del Hg sobre el transporte de agua en la planta a nivel celular y su relación con el estatus hídrico de ésta. Además, se presentan avances recientes en el conocimiento de las acuaporinas basados en la utilización del Hg como inhibidor de su actividad.Palabras clave adicionales: acuaporinas, conductividad hidráulica, raíces, estomas. | Heavy metals could affect hydric relationships in plants in many ways. Mercury inhibits activity of aquaporins, the proteins that form the chanels-transporters of water and, thus, affects water conductivity of cells and tissues of special root zones as well as volume of guard cells modifying stomatal movements. Mercury produces morphological changes in plants, the effects typical for other heavy metals, such as shortening of root or decrease in root elasticity, thus reducing effective area for water absorption. In leaves, the changes in number of stomata and trichomes caused by the effects of Hg alter the transpiration rates. In the present article, the effects of Hg over the water transport in plants at cellular level and whole hydric status of plants are revised. Additionally, the recent studies on aquaporin functioning are discussed, with Hg used as an agent to inhibit aquaporin activity.
Mostrar más [+] Menos [-]Performance of six clones of Eucalyptus in response to substrate water availability | Desempenho de clones de eucalipto em resposta a disponibilidade de água no substrato
2009
Tatagiba, S.D. | Pezzopane, J.E.M. | Reis, E.F. dos | Penchel, R.M.
Water immersion test for evaluation of physiologic potential of rice seeds | Teste de imersão em água para avaliação do potencial fisiológico de sementes de arroz Texto completo
2009
Wrasse, Cátia Fernanda | Menezes, Nilson Lemos | Bortolotto, Rafael Pivotto
The objective of this work was to determine the best condi ons for the water immersion test and to evaluate its e ciency for applica on on rice seeds. Five seed lots of cv. rice IRGA 417 were used, which were submited to immersion treatments tests for periods of 24, 48, 72, 96 and 120 hours at 25 C. After treatments, germina on test, par al and total length of seedlings and seedlings dry mater were accomplished. Water immersion test in the condi on of 24 hours of immersion of the seeds at 25 C, with evalua on of normal seedlings developed, is viable to evaluate vigor on rice seeds. | O presente trabalho teve por objeivo determinar as condiç es para a conduç o do teste de imers o em água como teste de vigor em sementes de arroz. Uilizaramrse cinco lotes de sementes de arroz cv. IRGA 417, caracterizados quanto à qualidade fisiológica inicial e submeidos aos tratamentos de imers o em água por períodos de 24, 48, 72, 96 e 120 horas a 25 C. Após os tratamentos, foram realizadas as avaliaç es de germinaç o, comprimento da raiz, parte aérea e total e massa seca das plântulas. O teste de imers o em água na condiç o de 24 horas a 25 C, seguido da avaliaç o da formaç o de plântulas normais, é viável para avaliar o potencial fisiológico de sementes de arroz.
Mostrar más [+] Menos [-]Adaptação de equipamento de geração de gases oxidantes para aplicação na desinfecção de água | Adaptation of generator oxidant gases equipament to aplication in water disinfection Texto completo
2009
Oliveira, Silvestre Zechinelli de | Tinôco, Adelson Luiz Araújo | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4787553U8 | Borges, Alisson Carraro | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4706302U9 | Souza, Cecília de Fátima | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4784862P9 | Tinôco, Ilda de Fátima Ferreira | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783628D6 | Nascimento, José Wallace Barbosa do | http://lattes.cnpq.br/9274991135144621 | Rezende, Ana Augusta Passos | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4786153D5
Human consumption of water outside of the microbiological standards for drinking constitutes a health and disease risk factor. Through the process of infiltration in the soil, groundwater may be contaminated by the waste generated by human activity and deposited in the soil, waterways or air. The consumption of water in natura, captured in a spring, may lead to the risk of disease. One of the alternative technologies for disinfecting water that has shown promise is the generation of an oxidant solution in loco. The electrochemical reaction of sodium chloride produces oxidizing gases, which reacts with the water to produce the hypochlorite ion in balance with hypochlorous acid, along with traces of other oxidants. In the present study the development of a device based on an imported model that uses this type of technology wassought in order to reduce the cost of acquisition and makeit more available to disadvantaged communities with water quality issues. The evaluation of the efficiency of this technology in disinfecting water with different qualities (color and turbidity) was also sought, using total coliforms and Escherichia coli as indicator organisms of contamination. In each experimentthe quality of untreated water, and water after adding the oxidant was examined on turbidity, true color, residual chlorine, pH, temperature, and quantification of microorganism indicators. In the experiments performed we found that the adapted equipment showed to be as efficient in the production of disinfectant agents as the original equipment. In the microbiological assays performed on water contaminated with E. coli (synthesized water in a laboratory and natural) and total coliforms (natural water), the inactivation of these organisms was observed to be effective with the use of gases that came from the adapted equipment, taking into account the content of chlorine in water treated with the equipment. | Human consumption of water outside of the microbiological standards for drinking constitutes a health and disease risk factor. Through the process of infiltration in the soil, groundwater may be contaminated by the waste generated by human activity and deposited in the soil, waterways or air. The consumption of water in natura, captured in a spring, may lead to the risk of disease. One of the alternative technologies for disinfecting water that has shown promise is the generation of an oxidant solution in loco. The electrochemical reaction of sodium chloride produces oxidizing gases, which reacts with the water to produce the hypochlorite ion in balance with hypochlorous acid, along with traces of other oxidants. In the present study the development of a device based on an imported model that uses this type of technology wassought in order to reduce the cost of acquisition and makeit more available to disadvantaged communities with water quality issues. The evaluation of the efficiency of this technology in disinfecting water with different qualities (color and turbidity) was also sought, using total coliforms and Escherichia coli as indicator organisms of contamination. In each experimentthe quality of untreated water, and water after adding the oxidant was examined on turbidity, true color, residual chlorine, pH, temperature, and quantification of microorganism indicators. In the experiments performed we found that the adapted equipment showed to be as efficient in the production of disinfectant agents as the original equipment. In the microbiological assays performed on water contaminated with E. coli (synthesized water in a laboratory and natural) and total coliforms (natural water), the inactivation of these organisms was observed to be effective with the use of gases that came from the adapted equipment, taking into account the content of chlorine in water treated with the equipment. | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Mostrar más [+] Menos [-]V Foro Mundial del Agua Estambul 2009: tendiendo puentes hacia el trabajo conjunto en torno al agua, la experiencia peruana Texto completo
2009
Presenta, en el marco del V Foro Mundial del Agua (Estambul, 2009), los logros alcanzados y las principales medidas de gestión y conservación sostenible alcanzadas. Asimismo, muestra aspectos referidos a la gestión de los recursos hídricos al 2020 enfocado al crecimiento y el desarrollo, implementación de la gestión integrada de recursos hídricos (GIRH), suministro de agua y servicios sanitarios para todos, gestión del agua para la alimentación y el medio ambiente, cambio climático y manejo del riesgo, avances del Estado Peruano en el cumplimiento de los Objetivos de Desarrollo del Milenio, entre otros aspectos.
Mostrar más [+] Menos [-]UTILIZAÇÃO DA ÁGUA SUBTERRÂNEA NA INDÚSTRIA DE ALIMENTOS Texto completo
2009
Josafá Ribeiro de Oliveira | Rosiane Freire | Daniel Cardoso | Artur Baphyda
O objetivo do trabalho foi comentar a água subterrânea utilizada como matéria prima nos produtos envasados na FLY, com ênfase no histórico da indústria, como também, uma síntese sobre o futuro sistema de tratamento das águas residuárias e a aplicação dos produtos NORUST / FERBAX em um poço de 120 metros de profundidade no aqüífero Barreiras, que apresentou teor de ferro acima 5mg/l. Assim sendo, as indústrias de alimentos, utilizam água subterrânea para atender a demanda das suas necessidades, onde essas empresas de relevante significado econômico e social para os municípios e estados.
Mostrar más [+] Menos [-]Impacto da água de drenagem em solos irrigados. Texto completo
2009
MELO, R. F. de | BRITO, L. T. de L. | LEITE, W. de M.
Captação de água de chuva em cisternas rurais. Texto completo
2009
CAVALCANTI, N. de B. | BRITO, L. T. de L.