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Variáveis de eficiência, manejo de irrigação e de produção da bananeira cultivar BRS Tropical sob diferentes sistemas de mircroaspersão e gotejamento; Variables efficiency, irrigation management and yield of banana cv BRS Tropical under different systems of microsprinkling and drip

Silva, Alisson Jadavi Pereira da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/12/2009 Português
Relevância na Pesquisa
56.39%
A agricultura irrigada, por se tratar do setor produtivo que mais demanda água, tem sofrido continuas pressões para garantir a produção de alimentos com uso eficiente da água. Diante disto, objetivou-se com este trabalho estudar: (i) o efeito de diferentes sistemas de irrigação localizada (microaspersão e gotejamento) sob diferentes configurações na produtividade da bananeira BRS Tropical; (ii) avaliar a distribuição de raízes das plantas irrigadas por esses sistemas; (iii) calcular a eficiência de aplicação de água desses sistemas na cultura da bananeira e (iv) definir o posicionamento de sensores de água no solo para monitoramento da irrigação sob os sistemas considerados. O experimento foi conduzido nos campos experimentais da Embrapa Mandioca e Fruticultura Tropical, no qual foram estudados diferentes sistemas de irrigação localizada na cultura da bananeira BRS Tropical. Verificou-se que não houve efeito das diferentes configurações dos sistemas de irrigação por microaspersão nas variáveis de produção da bananeira BRS Tropical, o mesmo ocorrendo com as plantas irrigadas por diferentes configurações de sistemas de gotejamento. Entretanto, a produtividade da bananeira foi maior quando irrigada por sistemas de microaspersão do que por sistemas de gotejamento. A profundidade efetiva das raízes da bananeira irrigada por microaspersão e gotejamento foram 0...

Sistemas de irrigação de canais radiculares: avaliação radiográfica, histopatológica, histomicrobiológica e histoenzimológica, em dentes de cães com lesão periapical; Root canal irrigation systems: radiographic, histopathological, histomicrobiological and histoenzymological evaluation in dogs' teeth with apical periodontitis

Romualdo, Priscilla Coutinho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/06/2013 Português
Relevância na Pesquisa
56.34%
O fundamento do sucesso da terapia endodôntica é baseado no controle da contaminação microbiana presente no sistema de canais radiculares. Com essa finalidade, novos sistemas de irrigação têm sido desenvolvidos, demonstrando maior eficácia e segurança, destacando-se a irrigação por Pressão Apical Negativa (ANP) e a Irrigação Ultrassônica Passiva (PUI). O presente estudo in vivo teve como objetivo comparar a ANP e a PUI no reparo apical e periapical de dentes de cães com lesão periapical crônica, tendo como controle a irrigação convencional por Pressão Positiva (PP). Um total de 60 canais radiculares de pré-molares, com lesões periapicais experimentalmente induzidas, foram submetidos ao tratamento endodôntico em sessão única. Radiografias periapicais foram realizadas após a indução das lesões periapicais. Os dentes foram aleatoriamente divididos em 3 grupos: Grupo I - Irrigação por Pressão Apical Negativa (n=20 canais radiculares); Grupo II - Irrigação Ultrassônica Passiva (n=20 canais radiculares) e Grupo III - Irrigação por Pressão Positiva (controle) (n=20 canais radiculares). Após 180 dias, os animais foram eutanasiados, as peças removidas e submetidas ao processamento histotécnico para a análise histopatológica morfológica e morfométrica...

Análise comparativa da irrigação convencional, ultrassônica e sistema EndoSafe na remoção do magma dentinário do terço apical de raízes curvas; Comparative analysis of conventional irrigation, ultrasonic and EndoSafe system in removing the smear layer from the apical third of curved root

Kreling, Thalia Ferreira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/06/2014 Português
Relevância na Pesquisa
56.26%
O presente estudo teve por objetivo avaliar in vitro a eficiência dos sistemas de irrigação (convencional, ultrassônica e EndoSafe), na remoção do magma dentinário de canais mesiais curvos de molares inferiores, por meio de microscopia eletrônica de varredura. Foram utilizados canais mesiais com curvatura entre 200 e 400, de 47 molares inferiores, preparados com Reciproc (instrumento R25). Destes, dois condutos foram utilizados como controle negativo, e os outros foram divididos aleatoriamente em três grupos experimentais conforme a sua irrigação final: IC irrigação convencional com seringa e agulha; PUI irrigação ultrassônica passiva; EndoSafe irrigação com o sistema EndoSafe. Em todos os grupos foram utilizados 5mL de EDTA e 5mL de NaOCl por 30 segundos cada. A observação da região apical, após clivagem, foi realizada através de microscopia eletrônica de varredura em aumento de 1000X. Posteriormente, as imagens obtidas foram avaliadas por 3 examinadores calibrados pelo sistema de três pontos. Da análise dos resultados, pelo teste de Kruskal-Wallis, pode-se observar que o grupo ultrassônico e o EndoSafe apresentaram melhores resultados quando comparados ao grupo convencional, com diferença estatística entre os grupos (PIU: 40%; EndoSafe: 26...

Desarrollo vegetativo de patrones cítricos cultivados en condiciones de invernadero bajo dos sistemas de riego; Vegetative development of citrus seedlings cultivated at greenhouse conditions and submitted to two irrigations systems

Schafer, Gilmar; Souza, Paulo Vitor Dutra de; Koller, Otto Carlos; Schwarz, Sergio Francisco
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
56.22%
En el presente estudio se evaluó el desarrollo vegetativo de patrones cítricos cultivados en invernadero bajo dos sistemas de riego. El experimento se realizó en la Estação Experimental Agronômica de la Universidade Federal do Rio Grande do Sul, ubicada en Eldorado do Sul, Rio Grande do Sul, Brasil, entre los meses de septiembre de 2003 y abril de 2004, totalizando 225 días de experimentación. El diseño experimental fue de parcelas subdivididas, en factorial 2 x 3, con 4 repeticiones de 22 contenedores cada. En las parcelas principales se evaluaron los sistemas de riego (microaspersión y capilaridad) y en las subparcelas los patrones cítricos Poncirus trifoliata (L.) Raf., citrangero ‘C37’ [P. trifoliata x Citrus sinensis (L.) Osb. cv. Pêra] y lima ‘Rangpur’ (C. limonia Osb.). En condiciones de invernadero los patrones cítricos presentan un desarrollo vegetativo más rápido bajo riego por capilaridad respecto a la microaspersión. Los patrones cítricos evaluados presentan desarrollos vegetativos distintos, donde el citrangero ‘C37’ supera a los demás.; The aim of the present work was to evaluate the vegetative development of citrus rootstock seedlings cultivated under greenhouse conditions with two irrigation systems. The experiment was conducted at the Estação Experimental Agronômica ...

Economic viability and selection of irrigation systems using simulation and stochastic dominance

Saad, João Carlos Cury; Duenhas, Luiza Helena; Mariño, Miguel A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 1865-1873
Português
Relevância na Pesquisa
66.43%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); In humid areas, irrigation systems are used to increase the crop yield. The selection of irrigation system to be used is a decision made under uncertainty. This paper shows a procedure that is an association between Monte Carlo simulation method and the criterion of Stochastic Dominance to analyze the viability and identify the best economic option under risk condition. To illustrate the applicability of the procedure, three types of irrigation systems are evaluated to be used in a citrus orchard in Sao Paulo State, Brazil. The irrigation systems evaluated are: drip, microirrigation, and traveling sprinkler. The decision indicator is the present value of net benefit associated with the increase of yield obtained with the irrigation system adopted. The Monte Carlo simulation method is used to generate the cumulative distribution of the present value for each one of the irrigation systems. These curves allow to analyze the economic viability of the three irrigation systems. According to the First Degree Stochastic Dominance, traveling sprinkler system was the best alternative with 95.7% probability of obtaining a positive present value. The second best option was the microirrigation with 82.7% and the worst result (57.3%) was obtained with drip irrigation.

Relationship between citrus productivity and indicators of uniformity in trickle irrigation system

Saad, João Carlos Cury; Da Silva Jr., Hélio Moreira
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 4621-4627
Português
Relevância na Pesquisa
56.3%
In trickle irrigation systems, the design is based on the pre-established emission uniformity (EU) which is the combined result of the equipment characteristics and its hydraulic configuration. However, this desired value of the EU may not be confirmed by the final project (in field conditions) and neither by the yield uniformity. The hypotheses of this research were: a) the EU of a trickle irrigation system at field conditions is equal to the emission uniformity pre-established in the its design; b) EU has always the lowest value when compared with other indicators of uniformity; c) the discharge variation coefficient (VC) is not equal to production variation coefficient in the operational unit; d) the difference between the discharge variation coefficient and the productivity variation coefficient depends on the water depth applied. This study aimed to evaluate the relationship between EU used in the irrigation system design and the final yield uniformity. The uniformity indicators evaluated were: EU, distribution uniformity (UD) and the index proposed by Barragan & Wu (2005). They were compared estimating the performance of a trickle irrigation system applied in a citrus orchard with dimensions of 400m x 600m. The design of the irrigation system was optimized by a Linear Programming model. The tree rows were leveled in the larger direction and the spacing adopted in the orchard was 7m x 4m. The manifold line was always operating on a slope condition. The sensitivity analysis involved different slopes...

Model to increase the lateral line length of drip irrigation systems

Saad, João Carlos Cury; Ludwig, Rafael
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 4628-4638
Português
Relevância na Pesquisa
56.29%
Non-pressure compensating drip hose is widely used for irrigation of vegetables and orchards. One limitation is that the lateral line length must be short to maintain uniformity due to head loss and slope. Any procedure to increase the length is appropriate because it represents low initial cost of the irrigation system. The hypothesis of this research is that it is possible to increase the lateral line length combining two points: using a larger spacing between emitters at the beginning of the lateral line and a smaller one after a certain distance; and allowing a higher pressure variation along the lateral line under an acceptable value of distribution uniformity. To evaluate this hypothesis, a nonlinear programming model (NLP) was developed. The input data are: diameter, roughness coefficient, pressure variation, emitter operational pressure, relationship between emitter discharge and pressure. The output data are: line length, discharge and length of the each section with different spacing between drippers, total discharge in the lateral line, multiple outlet adjustment coefficient, head losses, localized head loss, pressure variation, number of emitters, spacing between emitters, discharge in each emitter, and discharge per linear meter. The mathematical model developed was compared with the lateral line length obtained with the algebraic solution generated by the Darcy-Weisbach equation. The NLP model showed the best results since it generated the greater gain in the lateral line length...

Comparative analysis of main on-farm irrigation systems in Portugal

Sousa, Pedro L.; Silva, Luis Leopoldo; Serralheiro, Ricardo P.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: 6650 bytes; application/pdf
Português
Relevância na Pesquisa
66.4%
Traditional irrigation systems still cover a large area of irrigated lands in Portugal. The needs for competitiveness leads to the gradual abandon of traditional systems, resulting in social and economic impacts. Pressurised on-farm irrigation systems provide labour savings but imply important investments. Surface irrigation does not require expensive equipment and is low energy and low labour consuming, if modern systems are implemented. Flexible-pipe, gated-pipe, surge- flow valve and cablegation are the main equipment issues available to Portuguese farmers for modern surface irrigation practice. Conditions for application of these systems have been studied relative to different soil and topographic conditions. Plane land, either horizontal or sloped and undulated fields can be irrigated by surface systems, if a convenient design is accomplished. The adequacy of the irrigation systems has been evaluated and a cost-benefit study was carried out. A case study of a situation with undulated land, representative of South Portugal, is presented in this paper, comparing surface irrigation issues and a sprinkler system. Conclusions show a particular economic interest on adopting surge-valve, gated-pipe and cablegation.

Quality and maximum profit of industrial tomato as affected by distribution uniformity of drip irrigation system

Santos, Francisco Lúcio
Fonte: Irrigation and Drainage Systems Publicador: Irrigation and Drainage Systems
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
56.27%
Abstract The tomato industry reformed its system of payment by weight of tomato, introducing a corrective system based on percent level of fruit dry matter produced. Such a decision implies significant changes in the management of irrigation systems, with a need to emphasize the technological quality of the marketable product. Three levels of distribution uniformity of the irrigation system are analysed, and related production functions of crop yield and percent of dry matter are presented as well as their use on the optimisation of dry matter, expected revenues and seasonal applied water. Results are critically influenced by the distribution uniformity. They demonstrate the inter-relationship between crop production, percent fruit dry matter and irrigation management, and the importance of considering non-uniformity in the economic analysis of industrial tomato production. Decreases in uniformity lead to a reduction in dry matter production per unit land. Decreases in dry matter are also observed with increasing levels of seasonally applied water, with the optimal level always lower than the required for maximum yield. Such interaction suggests a continuous and inverse relationship between profit and water applied. However, due to the corrective system of payment...

Performance analysis of pressurized irrigation systems operating on-demand using flow-driven simulation models

Calejo, M.J.; Lamaddalena, N.; Teixeira, J.L.; Pereira, L.S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
Relevância na Pesquisa
56.39%
On-demand pressurized irrigation systems are designed to deliver water with the flow rate and pressure required by the farm irrigation systems, sprinkling or micro-irrigation, and respecting the time, duration and frequency decided by the farmers. Due to the variation in farm demand along the season and the day, a large spatial and temporal variability of flow regimes occurs in these systems, which may affect the performance of the farm systems and the yields of the irrigated crops. Therefore, there is a need to analyse those systems to identify and solve performance problems. In this research, two simulation models for the analysis of irrigation systems operating on-demand, ICARE and AKLA, are used and compared to assess the hydraulic performance of the irrigation network of the Lucefecit Irrigation System, in Southern Portugal. ICARE assesses the global performance of the irrigation system through the indexed characteristic curves, while AKLA provides for the identification of the relative pressure deficit and reliability at every hydrant. Both models adopt a flow-driven analysis approach, performing the analysis for multiple flow regimes. To support the hydraulic characterization of the system and for calibration of the steadystate hydraulic model...

Multicriteria analysis for irrigation sustainable development: design and selection of irrigation systems

Darouich, Hanaa
Fonte: ISA/UL Publicador: ISA/UL
Tipo: Tese de Doutorado
Publicado em //2014 Português
Relevância na Pesquisa
56.37%
Doutoramento em Engenharia dos Biossistemas - Instituto Superior de Agronomia; This study aimed to select the most sustainable irrigation methods able to obtain high water productivity considering economic aspects and water saving criteria for wheat and cotton in NE Syria. The models used are PROASPER for sprinkler, SADREG for surface and MIRRIG for drip irrigation. Multicriteria analysis (MCA) was used to rank a set of design alternatives considering water saving and economic priorities. For wheat, surface and sprinkler systems were applied. For cotton surface, sprinkler and drip methods were compared. All combinations were analysed for full and deficit irrigation. Results for cotton show that drip irrigation is better than graded furrows for water saving but not a good option for economic priority unless the yield price increases. Sprinkler systems for cotton are rarely advantageous. For wheat, sprinkler systems are better than borders from water savings perspectives, showing an increased water productivity, as well as in economic terms leading to higher farmer’s income. MCA proved to be a very useful tool in a water scarce region to select the most appropriate irrigation systems considering the users preferences.

Chemical treatment to unclogg dripper irrigation systems due to biological problems

Ribeiro,Túlio Assunção Pires; Paterniani,José Euclides Stipp; Coletti,Christiane
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2008 Português
Relevância na Pesquisa
56.22%
Many producers use drippers for trickle irrigation systems for flower production in the field and in protected environments. A frequent problem in this type of irrigation system is the clogging of drippers, which is directly related to water quality and filtering system efficiency. The objective of this study was to conduct an experimental investigation to evaluate the efficiency of using nitric acid and sodium hypochlorite to unclogg drippers due to the use of water with high algae content. The evaluation was conducted in six, 4216 m² greenhouses, each with two sectors comprised of ten spaces or lines, totaling 12 sectors of a dripper irrigation system in a rose producing property of Holambra, State of SP, Brazil. Chemical and physical analyses and the bacteriological count in water were carried out in the three water sources that supply the irrigation system to check the factors causing the clogging. Evaluations were carried out on water distribution uniformity in all sectors before and after chemical treatment in order to evaluate efficiency. The treatment improved water distribution uniformity and a lead to a reduction in the coefficient of variation (CV) for dripper flow in all sectors. There was a good correlation between CV and the water distribution uniformity index. Therefore...

Efficiency of water application of irrigation systems based on microsprinkling in banana plantations

Silva,Alisson Jadavi Pereira da; Coelho,Eugênio Ferreira; Miranda,Jarbas Honório de
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 Português
Relevância na Pesquisa
56.26%
Further food production may be limited by the reduced availability of water resources. Since irrigated agriculture is the productive sector that presents a higher demand of water, this sector has been under intense pressure in order to ensure food production with improved efficiency of water use. This study aimed to use the Time Domain Reflectometry (TDR) technique to measure percolation losses and to determine water application efficiency of banana (Musa spp.) trees using microsprinkler irrigation systems. Three systems were studied: (i) one 32 L h-1 microsprinkler for four plants; (ii) one 60 L h-1 microsprinkler for four plants; and (iii) one 60 L h-1 microsprinkler for two plants. Systems that replace water to the soil with the lowest variation of infiltrated water depths at different distances from plant pseudostem were the most efficient. The water application efficiency of microsprinkler irrigation systems using the (i), (ii), and (iii) microsprinkler systems were 85%, 80 % and 90 % respectively.

Sprinkler and drip irrigation in the organic tomato for single crops and when intercropped with coriander

Marouelli,Waldir Aparecido; Lage,Daniel Anacleto da Costa; Gravina,Cristina Silveira; Michereff Filho,Miguel; Souza,Ronessa Bartolomeu de
Fonte: Universidade Federal do Ceará Publicador: Universidade Federal do Ceará
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 Português
Relevância na Pesquisa
56.22%
The objective of this study was to evaluate the influence of both sprinkler and drip irrigation systems on the organic production of the tomato, cultivar Duradouro, when cultivated both as a single crop and intercropped with coriander. The experiment was carried out in the Distrito Federal, Brazil, using a randomized block design with six replications and a 2 x 2 factorial arrangement for the treatments. There was no significant interaction between the factors of irrigation system and cropping system. The productivity and mass of the tomato fruits were not affected by the treatments, but for the coriander, productivity was higher under the sprinkler system. Drip irrigation hindered the development of late blight (Phytophthora infestans) and reduced the percentage of rotten fruit, whereas the incidence of powdery mildew (Leveillula taurica) and infestation by the tomato leafminer (Tuta absoluta) were higher under the sprinkler system. The volume of soil exploited by the roots of tomato plants was higher with the sprinkler system, while the water productivity index with the drip system was 47% higher than with the sprinkler system. Firmer fruits were produced under drip irrigation. The cultivation system had a significant effect on the occurrence of insect pests...

Institutionalizing the informal: irrigation and government intervention in Bali

Lorenzen, Stephan; Lorenzen, Rachel P.
Fonte: Palgrave Macmillan; http://www.palgrave.com/ Publicador: Palgrave Macmillan; http://www.palgrave.com/
Tipo: Journal article; Accepted Version Formato: 8 pages
Português
Relevância na Pesquisa
56.22%
Although there is greater acceptance that farmers can manage their irrigation systems efficiently, many irrigation experts believe that a shift from informal to more formal management strategies will lead to even better water-flow management. This article examines a case in Bali where attempts to introduce formal institutions lead to confusion within the farming community. We concluded that irrigation improvement projects need to engage with the local context and encourage a minimum of formal organization.

Cost Recovery and Water Pricing for Irrigation and Drainage : What Works?

Easter, K. William; Liu, Yang
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Brief; Publications & Research
Português
Relevância na Pesquisa
56.3%
No silver bullet exists to improve cost recovery or water use efficiency of irrigation systems. However, many countries provide examples of successful reforms that policymakers and system managers can draw upon for inspiration and ideas. A successful system will have the appropriate mix of technology, management, policy, and institutional arrangements that facilitate transparent and efficient service delivery and increase farmer's willingness to pay and to use limited water resources more efficiently. This note is based on the larger volume of the same name, which outlines guidelines for designing a successful system for cost recovery and efficient water use and provides numerous case studies of successful implementation.

Institutional Reform for Irrigation and Drainage : Proceedings of a World Bank Workshop

Gonzalez, Fernando J.; Salman, Salman M.A.
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
Português
Relevância na Pesquisa
56.41%
The report consists of an introduction, and three separate, but inter-related parts. The introduction provides an overview of the workshop discussions, arguing that the irrigation sector is blamed for many environmental problems, suggesting to set the right incentives, and regulations, including stakeholders involvement, and partnerships to overcome sector obstacles. The first part looks at the institutional diversity in irrigation, and drainage sectors, reviewing institutional changes within components of the Bank's portfolio of irrigation, and drainage projects. It addresses the extent to which the Bank's major policy documents of the 1990s have shaped the portfolio, and suggests recommendations to promote institutional changes, and the introduction of alternative solutions, such as private sector involvement, to increase competition, service contracts, and intergovernmental agreements. The second part reviews the irrigation regulatory framework, arguing that participation of Water Users Associations (WUAs) in the management of irrigation systems...

Uniformidade de sistemas de irrigação localizada: validação de equações; Uniformity of localized irrigation systems: validation of equations

Favetta, Gilberto Manilli; Botrel, Tarlei Arriel
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2001 Português
Relevância na Pesquisa
56.22%
O coeficiente de uniformidade nos sistemas de irrigação localizada é importante por permitir a avaliação de sistemas ou somente projetados. Quanto aos diferentes métodos aplicáveis, é importante que se defina a correlação entre os mesmos, de forma a permitir a comparação entre os equipamentos. Para avaliação da eficácia de equações de correlação entre os coeficientes de uniformidade de emissão, uniformidade de emissão absoluta e uniformidade estatística, foram comparados os resultados de sua aplicação com valores obtidos pelo uso convencional de cada um desses métodos. A avaliação foi feita a partir de dados obtidos pela aplicação dos três métodos em dois diferentes sistemas de irrigação por microaspersão implantados, tendo sido usado como referência para a avaliação os respectivos coeficientes de uniformidade calculados com base no censo das vazões dos emissores instalados. As baixas diferenças porcentuais entre os valores estimados pelas equações propostas e os obtidos pela aplicação convencional de cada método confirmam a sua validade, permitindo a estimativa da uniformidade de um dos métodos analisados a partir do valor obtido por outro dos métodos estudados.; The localized irrigation systems uniformity coefficient is important to allow evaluation of implanted or just projected systems. With regard to applicable different methods is important to define correlation between them...

Efficiency of water application of irrigation systems based on microsprinkling in banana plantations

Silva, Alisson Jadavi Pereira da; Coelho, Eugênio Ferreira; Miranda, Jarbas Honório de
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2013 Português
Relevância na Pesquisa
56.26%
Further food production may be limited by the reduced availability of water resources. Since irrigated agriculture is the productive sector that presents a higher demand of water, this sector has been under intense pressure in order to ensure food production with improved efficiency of water use. This study aimed to use the Time Domain Reflectometry (TDR) technique to measure percolation losses and to determine water application efficiency of banana (Musa spp.) trees using microsprinkler irrigation systems. Three systems were studied: (i) one 32 L h-1 microsprinkler for four plants; (ii) one 60 L h-1 microsprinkler for four plants; and (iii) one 60 L h-1 microsprinkler for two plants. Systems that replace water to the soil with the lowest variation of infiltrated water depths at different distances from plant pseudostem were the most efficient. The water application efficiency of microsprinkler irrigation systems using the (i), (ii), and (iii) microsprinkler systems were 85%, 80 % and 90 % respectively.

A catchment-scale irrigation systems model for sugarcane part 2: model application

Moult,NG; Lecler,Nl; Smithers,Jc
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 Português
Relevância na Pesquisa
56.28%
In the face of growing uncertainty regarding water availability to irrigated agriculture in South Africa, a computer simulation model, ACRUCane, has been developed to provide management information to irrigators of sugarcane and catchment water managers. ACRUCane can be used to simulate catchment hydrology, sugarcane yield, irrigation water requirement and water supply. The development and verification of the model is described in a companion paper. In order to illustrate the application of the model, it was configured to represent a catchment in northern KwaZulu-Natal (Pongola) with runoff feeding into a dam which supplied water for a dragline irrigation system. Various 'what if' scenarios representing potential changes to the irrigation system or management practice were assessed. Analysis of the simulated scenarios showed the interdependencies between irrigation application uniformity and irrigation scheduling. Improved application uniformities needed to be combined with improved scheduling to obtain maximum benefit, estimated to be approximately R3 000/ha. Improved scheduling resulted in fewer seasons with water shortages and crop yield reductions. Replacing the dragline system with subsurface drip (SSD) resulted in gains in the proportion of applied water used beneficially and a small increase in crop yields. However...