Segui questo link per vedere altri tipi di pubblicazioni sul tema: Irrigation.
Tesi sul tema "Irrigation"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-50 saggi (tesi di laurea o di dottorato) per l'attività di ricerca sul tema "Irrigation".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi le tesi di molte aree scientifiche e compila una bibliografia corretta.
1
Mohamed, Nahla Abdel-Fattah Hemdan. "Irrigation systems". Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2014. http://dx.doi.org/10.18452/16977.
Testo completoAbstract (sommario):
In der Wintersaison 2005-2006 wurde ein Split-Split Plot-Design Feldversuch mit drei Wiederholungen für jede Behandlung von Kartoffeln, als Indikatorpflanze, unter den ariden Bedingungen der Kharga Oasis in der Westlichen Wüste von Ägypten durchgeführt. Drei Bewässerungslevel (100 %, 80 %, und 60 % of ETc) mit Tröpfchenbewässerung, zwei Mulchvarianten (Zuckerrübenabfall ohne und mit 24 ton ha-1) und 4 Kompostraten (0, 12, 24, und 36 ton ha-1) wurden getestet. Generell und als Ergebnis einer Regressionsanalyse der Versuchsvarianten ohne Kompost war die beste Variante die Tröpfchenbewässerung bei 80% ETc unabhängig ob gemulcht oder nicht gemulcht wurde. Andererseits die Variante mit 36 t Kompost und mit 24 t Mulch ergab die besten Ergebnisse bei 60% of ETc sowohl beim Ertrag und den Ertragskomponenten, bei den hydrophysikalischen Eigenschaften, bei der Bodenwasserretention, beim Wasserverbrauch, bei den Pflanzenkoeffizienten, der Wassernutzungseffizienz, der Düngernutzungseffizienz sowie beim Nettogewinn. Wird die Rate der Kompostgabe aber auf 24 ton ha-1 reduziert, die höchsten Nettogewinne bei der lokalen Vermarktung als auch signifikant beim Kartoffelexport werden erreicht.Under the arid condition of Kharga Oasis in the Western Desert of Egypt, split-split plot design field experiment with three replications for each treatment using potato as an indicator plant was carried out during the winter season 2005-2006. Three irrigation levels of water regime (100 %, 80 %, and 60 % of ETc) using drip irrigation system, two treatments of soil covering (sugar cane wastes at the rate of 0 and 24 ton /ha) and compost rates (0, 12, 24, and 36 ton ha-1) were tested. In general and as a result of the triple interaction among the studied treatments, using drip irrigation either with soil mulching or not, 80 % of ETc as a water regime was the best. On the other hand, reducing drip irrigation water level at 60% of ETc in mulched soil that was treated with 36 ton ha-1 of compost recorded the highest values yield and yield components, soil hydrophysical properties, soil water retention, water consumption, crop coefficients, water economy water use efficiency, fertilizer use efficiency, net profit. But reducing the compost rate to 24 ton ha-1 attained the highest net profit for local potato consumption and achieved the best significant net profit for exportation.
2
Martin, E. C., R. Wegge e M. Sheedy. "Effects of High Frequency Irrigation on Irrigation Uniformity II". College of Agriculture, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/197490.
Testo completoAbstract (sommario):
Another year of data was collected to determine the effects of high frequency irrigation on irrigation uniformity in cotton production. A field located at the Marana Agricultural Center was split into two treatments. Treatment one was irrigated at approximately 35% depletion of available water in the plant rootzone. Treatment two was irrigated at approximately 65% depletion in the crop rootzone. Increased frequency of irrigation has shown improved yields in many cotton studies. However, these more frequent and lighter irrigation applications may cause problems with irrigation uniformity. Frequent rains during critical time periods made it difficult to ascertain the impact of the irrigation schedule on uniformity. However, the less frequent, heavier application rate did result in a more uniform irrigation.
3
Martin, E. C., G. Laine e M. Sheedy. "Effects of High Frequency Irrigation on Irrigation Uniformity III". College of Agriculture, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/211315.
Testo completoAbstract (sommario):
Data was collected for a third season to determine the effects of high frequency irrigation on irrigation uniformity in cotton production. The past two seasons indicated that high frequency irrigation worked better on sandier soils than soils containing high clay contents. Although no significant differences were found, higher yields were obtained on a site with a relatively high sand content. A field located at the Maricopa Agricultural Center was split into two treatments. Treatment 1 was irrigated at approximately 35% depletion of available water in the plant rootzone. Treatment 2 was irrigated at approximately 50% depletion in the crop rootzone. Although the yield data from Treatment 1 was higher on the average, statistically, there was no difference between the two treatments.
4
Andriyas, Sanyogita. "Analysis of Irrigation Decision Behavior and Forecasting Future Irrigation Decisions". DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1359.
Testo completoAbstract (sommario):
Farmers play a pivotal role in food production. To be economically successful, farmers must make many decisions during the course of a growing season about the allocation of inputs to production. For farmers in arid regions, one of these decisions is whether to irrigate. This research is the first of its kind to investigate the reasons that drive a farmer to make irrigation decisions and use those reasons/factors to forecast future irrigation decisions. This study can help water managers and canal operators to estimate short-term irrigation demands, thereby gaining information that might be useful in management of irrigation supply systems. This work presents three approaches to study farmer irrigation behavior: Bayesian belief networks (BBNs), decision trees, and hidden Markov models (HMMs). All three models are in the class of evolutionary algorithms, which are often used to analyze problems in dynamic and uncertain environments. These algorithms learn the connections between observed input and output data and can make predictions about future events. The models were used to study behavior of farmers in the Canal B command area, located in the Lower Sevier River Basin, Delta, Utah. Alfalfa, barley, and corn are the major crops in this area. Biophysical variables that are measured during the growing reasons were used as inputs to build the models. Information about crop phenology, soil moisture, and weather variables were compiled. Information about timing of irrigation events was available from soil moisture probes installed on some agricultural fields at the site. The models were capable of identifying the variables that are important in forecasting an irrigation decision, classes of farmers, and decisions with single and multi-factor effect regarding farmer behavior. The models did this across years and crops. The advantage of using these models to study a complex problem like behavior is that they do not require exact information, which can never be completely obtained, given the complexity of the problem. This study uses biophysical inputs to forecast decisions about water use. Such forecasts cannot be done satisfactorily using survey methodologies. The study reveals irrigation behavior characteristics. These conform to previous beliefs that a farmer might look at crop conditions, consult a neighbor, or irrigate on a weekend if he has a job during the week. When presented with new data, these models gave good estimates for probable days of irrigation, given the past behavior. All three models can be adequately used to explore farmers' irrigation behavior for a given site. They are capable of answering questions related to the driving forces of irrigation decisions and the classes of subjects involved in a complex process.
5
Brown, Peter Derek. "Optimal irrigation scheduling". Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2008. http://hdl.handle.net/10092/1255.
Testo completoAbstract (sommario):
An optimal stochastic multi-crop irrigation scheduling algorithm was developed which was able to incorporate complex farm system models, and constraints on daily and seasonal water use, with the objective of maximising farm profit. This scheduling method included a complex farm simulation model in the objective function, used decision variables to describe general management decisions, and used a custom heuristic method for optimisation. Existing optimal schedulers generally use stochastic dynamic programming which relies on time independence of all parameters except state variables, thereby requiring over-simplistic crop models. An alternative scheduling method was therefore proposed which allows for the inclusion of complex farm system models. Climate stochastic properties are modelled within the objective function through the simulation of several years of historical data. The decoupling of the optimiser from the objective function allows easy interchanging of farm model components. The custom heuristic method, definition of decision variables, and use of the Markov chain equation (relating an irrigation management strategy to mean water use) considerably increases optimisation efficiency. The custom heuristic method used simulated annealing with continuous variables. Two extensions to this method were the efficient incorporation of equality constraints and utilisation of population information. A case study comparison between the simulated annealing scheduler and scheduling using stochastic dynamic programming, using a simplistic crop model, showed that the two methods resulted in similar performance. This demonstrates the ability of the simulated annealing scheduler to produce close to optimal schedules. A second case study demonstrates the ability of the simulated annealing scheduler to incorporate complex farm system models by including the FarmWi$e model by CSIRO in the objective function. This case study indicates that under conditions of limited seasonal water, the simulated annealing scheduler increases pasture yield returns by an average of 10%, compared with scheduling irrigation using best management practice. Alternatively expressed, this corresponds to a 20-25% reduction in seasonal water use (given no change in yield return).
6
Kamwamba-Mtethiwa, Jean Tiyamika. "Sustainable irrigation development : the adoption of small-scale pumped irrigation in Malawi". Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/10005.
Testo completoAbstract (sommario):
There has been an increased interest on small-scale pumped irrigation (SSPI) in Sub Saharan Africa (SSA), however little is known on the adoption processes behind this technology. Moreover, the conditions for successful SSPI adoption remain largely unexplored. This research aims to achieve a deeper understanding of the present adoption processes to inform future policy. The thesis was framed around the diffusion of innovations model (Rogers 2003), using the systematic review methodology and field surveys. Interviews involving 212 farmers and 25 other stakeholders were conducted between 2013 and 2014 within 3 districts in Malawi. The responses were analysed using descriptive statistics and content analysis. The systematic review revealed that evidence relating to pump performance in SSA was limited, lacked standards and confined within particular regions. The field surveys identified that four different pumped systems have been adopted by farmers in Malawi; group treadle, individual treadle, group motorized and individual motorized. Farmers generally prefer individually managed pumps that are easy to operate and fit in with their existing farming practices. Adoption is driven either by the attributes of self-motivated farmers or by incentives such as free or subsidized pumps. While adoption by self-motivated farmers is consistent with Rogers (2003) model, adoption due to incentives shows differences. The research proposes a modification to the Rogers (2003) model and revised definition of success in SSPI adoption, leading to a new framework showing pathways of success. This framework identifies the routes taken by farmers who successfully adopt or discontinue using pumps. Incentive farmers are typically the poorer; these need continued external support to survive the learning curve. For self-motivated farmers, their higher socio-economic status supports successful adoption. To ensure sustainability, SSPI promoters need to offer continued support to incentive farmers and/or reduce barriers to accessing the pumps for self-motivated farmers.
7
Darouich, Hanaa. "Multicriteria analysis for irrigation sustainable development: design and selection of irrigation systems". Doctoral thesis, ISA/UL, 2014. http://hdl.handle.net/10400.5/7340.
Testo completoAbstract (sommario):
Doutoramento em Engenharia dos Biossistemas - Instituto Superior de AgronomiaThis 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.
8
Young, Lauren. "Irrigation Methods and Their Effects on Irrigation Water Efficiency in High Tunnels". Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1609101/.
Testo completoAbstract (sommario):
Improving water efficiency is and will continue to be a top concern to meet the world food production demands for a growing population. By having a clear understanding of water efficiencies, communities will be able to address these concerns from an economic standpoint and use more productive methods to grow food and limit water consumption. This study examines the water efficiencies of three irrigation methods over a single growing season in southeastern Oklahoma. Two crops, tomatoes and cucumbers, were grown using drip irrigation, a self-wicking container, and a non-circulating hydroponics barrel. Results at the end of the season showed the drip irrigation method had the highest water efficiency in terms of yield of product over water applied for both crops. The drip irrigation method also had the lowest associated set up costs and second lowest time requirements after the hydroponics method. These results were found to be consistent with other studies that compared drip irrigation to other irrigation methods and showed drip to have the highest water efficiencies.
9
Scherer, T., D. Slack, J. Watson e F. Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics". College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/204858.
Testo completoAbstract (sommario):
Three methods were used to schedule irrigations on replicated plots at the Maricopa Ag Center using DPL 90 cotton. The three methods were: a soil water balance model based on historic consumptive use curves, a soil water balance model based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the C.W.S.I. A potassium-bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was duplicated at the Safford Experiment Station and is presented in another report. Results from the 1988 data indicate that there was no significant difference in yield between the 3 methods. There was a significant difference in water applied; the historic consumptive-use curves was the lowest and the Penman equation method was the highest.
10
Scherer, T., D. Slack, J. Watson e F. Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics". College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/208305.
Testo completoAbstract (sommario):
Three methods were used to schedule irrigations during 1989 on replicated plots at the Maricopa Ag Center using DPL 90 cotton. This is a continuation of the research initiated in 1988 using the same field The three methods were; a soil water balance model based on historic consumptive use curves, a soil water balance model based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the C.W.S.I. A potassium- bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was again duplicated at the Safford Experiment Station and is presented in another report. Results from this years data indicate that there was no significant difference in yield among the three methods. However, as in 1988 there was a significant difference in water applied with historic consumptive use (ERIE) the lowest and the Penman equation method (CHECKBOOK) the highest.
11
Scherer, Tom, Don Slack, Jack Watson e Fred Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics". College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/208344.
Testo completoAbstract (sommario):
Three methods were used to schedule irrigations during the 1990 growing season on replicated plots at the Maricopa Ag Center using DPL 90 cotton. This is the final report of the research initiated in 1988. The three methods were: a soil water balance model based on historic consumptive use curves (ERIE), a soil water balance model (AZSCHED) based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the Crop Water Stress Index (CWSI). A potassium- bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was again duplicated at the Safford Experiment Station and is presented in another report. Results from this years data indicate that there was no significant difference in yield between the 3 methods. Also, there was no significant difference in the amount of applied irrigation water. The AZSCHED and ERIE methods will be developed into Extension educational tools and released for use by growers.
12
Bernot, Marc. "Transport optimal et irrigation". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2005. http://tel.archives-ouvertes.fr/tel-00132078.
Testo completoAbstract (sommario):
L'objet de cette thèse est de modéliser et d'étudier des structures d'irrigation telles les nervures des feuilles, réseau sanguin, poumons,etc. Un modèle généralisant le problème de Gilbert Steiner est introduit ; on étudie alors les propriétés d'existence, de stabilité et régularité. Des algorithmes sont alors proposés pour la simulation.
13
Galganov, Yvonne T. (Yvonne Tamara). "Subsurface irrigation of soybean". Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70168.
Testo completoAbstract (sommario):
A field experiment was conducted on a homogeneous sandy soil and a layered soil of southern Quebec from 1988 to 1990. This was done in order to evaluate the yield response of indeterminate soybean to subsurface irrigation and to determine the performance of subsurface irrigation in a layered soil. It was found that indeterminate soybean varieties increase their yield by approximately 30% for two out of three years. Soybean are very sensitive to competition between themselves as well as with weeds. This sensitivity is increased during subsurface irrigation. Weeds were more prominent in the irrigated area. It was concluded that the soybean yields are functions of water table depth, percent weed and plant population density. The minimum allowable water table depth for soybean was found to be 45 cm. At a water table depth greater than 95 cm no yield response was observed.Water table management is not only possible but very functional in the layered soils of southern Quebec. It was found that surplus water did not drain from the irrigated area until the water table anywhere in this area was 10 cm higher than the elevation of the overflow pipe in the control chamber. It was therefore concluded that a water table depth range of 10 cm should be included in the design of the water table control system to allow for the effects of rain.
14
Call, Robert, e Cado Daily. "Drip Irrigation: The Basics". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/144820.
Testo completoAbstract (sommario):
2 pp.Drip irrigation is the slow, measured application of waer through devices called emitters. Now a wide variety of quality products has been developed to make drip irrigation reliable and easy.
15
Ottman, M. J., e B. R. Tickes. "Alfalfa Irrigation Termination, Yuma". College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/201407.
Testo completoAbstract (sommario):
Alfalfa irrigation is often withheld as a water conservation measure in Arizona. The objective of this research was to test the hypothesis that alfalfa yield and stand can be permanently damaged by withholding irrigation water. Irrigation was terminated during the summer (July through October) or winter (November through February) on a Superstition sand in Yuma. Summer irrigation termination reduced plant density from 4 to 1.5 plants per square foot and reduced hay yield from 0.76 to 0.27 tons per acre per cutting after irrigation was resumed. Winter irrigation termination had no residual effect on yield or plant density. Termination of alfalfa irrigation can permanently damage stands and reduce yield on sandy soil.
16
Ottman, M. J., e R. L. Roth. "Alfalfa Irrigation Termination, Maricopa". College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/201408.
Testo completoAbstract (sommario):
Alfalfa irrigation is often withheld as a water conservation measure in Arizona. The objective of this research was to test the hypothesis that alfalfa can be permanently damaged by withholding irrigation water. Irrigation was terminated during the summer (July or August through September) or summer through winter (July or August through mid -March) on a Casa Grande sandy loam at Maricopa. Irrigation termination at Maricopa was not detrimental to stand although hay yields were depressed from 1.47 to 1.28 tons per acre following the second cycle of summer irrigation termination and from 1.57 to 1.23 tons per acre per cutting following summer through winter irrigation termination. Alfalfa water use was reduced by irrigation termination even after irrigation was resumed. Total nonstructural carbohydrates in the roots were never less than the control during irrigation termination but decreased relative to normally irrigated alfalfa when irrigation resumed.
17
Fox, Fred Andrew 1956. "Irrigation scheduling decision support". Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/288770.
Testo completoAbstract (sommario):
Irrigation scheduling using the soil water balance approach has been recommended to irrigators for many years. Reasonably good results are normally obtained by researchers using carefully quantified inputs. Irrigators in production agriculture may estimate inputs and then question the validity of the method when the irrigation recommendations conflict with present irrigation schedules. By associating each input with an interval representing possible bias based on the way the input was estimated, and solving the irrigation scheduling model using the intervals as inputs, the output was associated with an interval representing possible bias. This method was also used to evaluate possible bias associated with growing degree day based crop coefficient curves developed from Arizona crop consumptive use measurements. For comparison purposes, roughly estimated inputs based on irrigation system type, soil type, area weather data and available crop coefficient curves were used as default intervals. Improved input intervals consisted of observed irrigation system performance, soil property measurements, local weather data and theoretical improvements in crop coefficient curves. For surface irrigation, field observation of plant stress and soil water content showed the greatest potential to improve irrigation date predictions. For buried drip under a row crop, accuracy of the predicted daily irrigation rate was most improved by a better estimate of irrigation efficacy.
18
Fernandes, Samuel Lucas. "Avaliação da efetividade de diferentes protocolos de irrigação na limpeza do canal radicular". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/25/25147/tde-24112015-154911/.
Testo completoAbstract (sommario):
O objetivo desse estudo foi avaliar a capacidade de dissolução e remoção de biofilme formado in situ, na remoção de smear layer e debris empregando dez protocolos de irrigação final (solução fisiológica com ou sem agitação ultrassônica; ou hipoclorito de sódio como irrigante primário, seguido de solução salina, ou EDTA 17%, ou ácido peracético (PAA) 2%, ou Qmix, com ou sem agitação ultrassônica de ambas as soluções). Duzentos e trinta raízes bovinas foram seccionadas e cortadas com 15mm de comprimento e instrumentadas com o instrumento Reciproc R50. Para a análise da remoção de debris e smear layer foram separadas 100 raízes, que foram clivadas e, no terço apical de uma das metades radiculares, foi confeccionado um sulco longitudinal, simulando extensões de canais ovais, posteriormente preenchidos com detritos artificiais. Após esse procedimento na outra metade foi realizada a formação de smear layer com uma vigora instrumentação da parede com movimentos de limagem. Essas amostras foram levadas ao MEV para análise prévia. Essas metades, depois de justapostas, voltaram a mufla e foram realizados os protocolos de tratamento. A análise dos dados foi realizada por meio de scores. Para a análise da dissolução e viabilidade do biofilme in situ 130 raízes foram separadas preparadas com instrumento R25 e um disco de dentina foi retirado do terço médio com uma trefina. Esses discos foram inseridos em uma placa de hawley, que foi utilizada pelo pesquisador durante três dias. Os discos foram removidos e deixados por 48 horas em BHI, em estufa a 37oC. Após a contaminação os discos voltaram para a raiz de onde foram removidos e fixados com cera utilidade voltando a mufla, sendo tratados e avaliados. Setenta discos foram utilizados para análise da dissolução e viabilidade em confocal e as imagens obtidas foram avaliadas pelo software Bioimage. Sessenta discos foram utilizados para a análise da dissolução do biofilme em MEV, sendo avaliados pré e pós-tratamento. Na comparação entre os grupos para a remoção de smear layer foram encontradas diferenças estatisticamente significantes (P < 0.05) entre os protocolos que utilizavam EDTA e Qmix, com os protocolos utilizando somente solução salina e hipoclorito seguido de solução salina independente da agitação ultrassônica. Enquanto que para a ranhura houve uma diferença estatisticamente significativa entre os grupos que utilizaram PUI e os demais grupos. Tanto a agitação ultrassônica, quanto o uso do hipoclorito de sódio como irrigante primário influenciaram significativamente para a redução do biovolume e da viabilidade bacteriana. O grupo que utilizou o NaOCl, seguido do Qmix associados ao PUI apresentou os menores valores de viabilidade e a maior dissolução do biofilme. O QMix PUI e o PAA/PUI mostraram os melhores resultados de dissolução na análise em MEV.se diferenciando estatisticamente (P<0.05) dos demais grupos. Levando-se em conta todos os critérios analisados, o protocolo que se mostrou mais eficiente foi o NaOCl seguido do QMix e associados a PUI.The aim of this study was to evaluate the dissolution capacity and removal of biofilm formed in situ, in smear layer and debris removal and debris use ten final irrigation protocols (saline with or without ultrasonic agitation, or sodium hypochlorite as primary irrigating, and then used saline or 17% EDTA, or 2% peracetic acid (PAA), or Qmix, with or without ultrasonic agitation of both solutions). Two hundred and thirty bovine roots were sectioned and cut with 15mm in length and instrumented with Reciproc R50. For the analysis of removal of debris and smear layer were separated 100 roots, which were cleaved, and the apical third of the half of root, has a longitudinal groove made simulating extensions of oval canals, artificial subsequently filled with debris. After this procedure was performed on half the formation of smear layer with a force wall with instrumentation filing motions. These samples were taken to SEM prior to analysis. These halves, after juxtaposed, and again the flask were held treatment protocols. Data analysis was performed by means of scores. For the analysis of the dissolution and viability of the biofilm in situ roots 130 were prepared with R25 separate instrument and dentin disc was taken from the middle third with a trephine. These disks were inserted into a hawley plate, which was used by the researcher for three days. The discs were removed and left for 48 hours in BHI at 37oC. After contamination disks back to the root from which they were removed and fixed with wax utility returning to muffle being treated and evaluated. Seventy disks were used for analysis of dissolution and viability and confocal images were evaluated by Bioimage software. Sixty discs were used for the analysis of the dissolution of the biofilm SEM and are assessed before and after treatment. Comparing the groups for the removal of smear layer statistically significant differences were found (P <0.05) between the protocols used EDTA and Qmix with the protocols using only saline solution and hypochlorite followed by saline independent of ultrasonic agitation. While for the slot there was a statistically significant difference between the groups using PUI and the other groups. Both ultrasonic agitation, and the use of sodium hypochlorite as primary irrigant influenced significantly to the reduction of bacterial viability and biovolume. The group using the NaOCl, and then used Qmix associated with PUI had the lowest viability values and the highest dissolution of the biofilm. The QMix PUI and the PAA / PUI showed the best dissolution results in the analysis MEV.se differentiating statistically (P <0.05) from the other groups. Taking into account all the criteria analyzed, the protocol that was more efficient was the NaOCl and then used QMix and associated with PUI.
19
Begmatova, Anjela. "Irrigation system cost comparison model". Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Summer2008/A_Begmatova_080508.pdf.
Testo completo
20
Chitsa, Gilbert. "Analysis of entrepreneurial behaviour of smallholder irrigation farmers: empirical evidence from Qamata Irrigation scheme". Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1019769.
Testo completoAbstract (sommario):
Albeit much effort having been put to review the performance trend of smallholder irrigation farmers in South Africa. However, there seems to be a paucity of information regarding the level of entrepreneurship on these farmers. Most research works on smallholder irrigation farmers have mainly focused on livelihoods trajectory providing a review on how the welfare of the rural poor has been transformed after the introduction of irrigation schemes. With most research evidence indicating a high degree of underperformance on most smallholder irrigation schemes, this research attempted to investigate the level of entrepreneurship among the small holder irrigation farmers. In order to achieve the main research objective, a sample of 110 farmers drawn from Qamata irrigation scheme was interviewed and each farmer’s performance on the nine components of entrepreneurship was assessed. The aspects assessed to determine the farmer’s entrepreneurial behaviour were: planning ability, risk taking, achievement motivation, leadership ability, Cosmo politeness, decision making, and innovativeness and farming knowledge. Basing on previous studies which indicated entrepreneurial behaviour to be influenced by several factors the study also analysed the determinants of entrepreneurship among the irrigation farmers and a binary logistic regression model was used to establish the connection between various independent variables and the farmers’ entrepreneurial performance given as a total score of the nine components. Though the findings of the study revealed a prevalently low level of entrepreneurship among the smallholder irrigation farmers on Qamata irrigation scheme, a high proportion of the respondent farmers (65.5% and 60.5%) showed to have a high degree of achievement motivation and decision making ability, respectively. The observed trend thus reflected that smallholder farmers have a potential to become entrepreneurs and are willing to succeed. The binary model results revealed that the prevailing land tenure system will be a strong determinant of the farmer’s level of entrepreneurship. Equally, levels of training in farming, motive for farming and information seeking tendency also proved to have a significant influence on the degree of farmer entrepreneurship. Based on the results of this study recommendations have thus been drawn on the need for policies and practices aimed at promoting entrepreneurship and not dependency among farmers. Key focus areas identified include: the need to revise the current land ii tenure system on irrigation schemes, intensify on entrepreneurship training for both farmers and extension officers and regular on-farm training on new technologies.
21
Karlberg, Louise. "Irrigation with saline water using low-cost drip-irrigation systems in sub-Saharan Africa". Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209.
Testo completo
22
Goodman, Ryan. "Wi-fi evapotranspiration irrigation controller". Click here to view, 2010. http://digitalcommons.calpoly.edu/eesp/22/.
Testo completoAbstract (sommario):
Thesis (B.S.)--California Polytechnic State University, 2010.Project advisor: James Harris. Title from PDF title page; viewed on Apr. 19, 2010. Includes bibliographical references. Also available on microfiche.
23
De, Vries Tonny Tessa. "Irrigation scheduling with integer programming". Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273891.
Testo completo
24
Hermansson, Hanna, e Louise Lundblad. "Automatic irrigation system for plants". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264445.
Testo completoAbstract (sommario):
The purpose of this project was to develop an automatic irrigation system for plants. It is beneficial to have plants indoors. In addition to their air-purifying qualities, they have been proven to increase the productivity of employees at workplaces, as well as decrease the amount of sick leave. Three research question were investigated: how much energy the system requires and if it is possible to replace the energy source with an alternative energy source, how well the system stabilises and how a wireless regulation can be implemented. The final design consisted of a mictrocontroller which controlled the system, a water pump, a moisture level sensor and a plant on which everything was tested. The system was left during a four week period to see how well it managed. The project resulted in a system that managed to keep the plant alive. The energy demand of the system could be covered by solar cells instead of batteries.Syftet med detta projekt var att utveckla ett automatiskt bevattningssystem för växter. Det är fördelaktigt att ha växter inomhus. Bland annat har det bevisats att växter i kontorslandskap ökar produktiviteten hos de personer som arbetar där, samt att antalet uttagna sjukdagar minskar. Fortsättningsvis var det tre stycken forskningsfrågor som undersöktes, hur mycket energi kräver systemet och är det möjligt att ersätta energikällan med en alternativ energikälla, hur väl stabiliserar sig systemet samt hur kan en trådlös reglering implementeras. Den slutliga designen bestod av en mikrokontroller som styrde systemet, en vattenpump, en fuktighetssensor och en planta på vilken testerna utfördes. Systemet lämnades i fyra veckor för att se hur väl det klarade sin uppgift. Resultatet blev att växten överlevde vilket innebär att systemet fungerade. Möjligheten att byta ut batterierna mor solceller studerades och slutsatsen är att detta byte är möjligt.
25
Farr, C. R. "Salinity Distribution Under Drip Irrigation". College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204075.
Testo completo
26
Farr, C. R. "Comparison of Increased Irrigation Frequency". College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/204486.
Testo completo
27
Roth, R. L., e B. R. Gardner. "Vegetable Research Under Sprinkler Irrigation". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/214110.
Testo completo
28
Gardner, B. R., e R. L. Roth. "Asparagus Production Under Sprinkler Irrigation". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/214133.
Testo completo
29
Farr, C. R. "Planting Patterns Under Drip Irrigation". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219749.
Testo completoAbstract (sommario):
The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.Planting pattern 2x1 skip row cotton outyielded variable row 32"x44" per gross field acre under drip irrigation with saline water. Skip row planting in deep water areas appears to be a feasible selection with high water cost, reduced tubing requirement, lowered land rentals and increased yield response.
30
Kingdon, Lorraine B. "Double Duty for Irrigation Water". College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/295634.
Testo completo
31
Maluka, Pretty Mabel. "Rural livelihoods and agricultural production in smallholder irrigation schemes: The case of Hoxane Irrigation scheme". University of the Western Cape, 2017. http://hdl.handle.net/11394/5931.
Testo completoAbstract (sommario):
Magister Philosophiae - MPhil (LAS) (Land and Agrarian Studies)This mini-thesis explores rural livelihoods and agricultural production in smallholder irrigation schemes in South Africa. The study sought to determine the livelihoods of plot-holders and the various production practices employed by the farmers in Hoxane Irrigation Scheme in Mpumalanga Province. The overall objective is to contribute to the literature on government's smallholder irrigation scheme revitalization programme and the types of support required by plot-holders in order to take advantage of the opportunities that exist in smallholder irrigation schemes.
32
White, Simon Charles. "Partial rootzone drying and deficit irrigation in cotton for use under large mobile irrigation machines". University of Southern Queensland, Faculty of Engineering and Surveying, 2007. http://eprints.usq.edu.au/archive/00004778/.
Testo completoAbstract (sommario):
[Abstract]: There is currently a shortage of irrigation water available for cotton production in Australia due to recent climatic and legislative conditions. Some growers have responded to this water shortage by changing from traditional furrow irrigation to alternative irrigation systems such as centre pivots and lateral move irrigations(collectively known as large mobile irrigation machines – LMIMs). Improved efficiency of irrigation application, as well as labour savings, have been the main reasons for the increased adoption of LMIMs. The use of LMIMs also enables a higher level of control in water application in terms of irrigation volume, timing and placement. As a result, growers now have much greater control over soil moistureconditions which enables the implementation of improved irrigation management strategies that have the potential for improved crop water use productivity (yield/ML).Two irrigation strategies which have been demonstrated to achieve benefits in terms of crop water use are partial rootzone drying (PRD) and deficit irrigation (DI). PRDand DI involve manipulating the placement of irrigation water and the moisture deficit maintained in the root zone, respectively. Neither PRD nor DI is able to beapplied easily under furrow irrigation. However, both PRD and DI may be able to be implemented under LMIMs within the Australian cotton industry. Deficit irrigation has been shown to be effective at improving water use productivity in cotton, although it is not widely used within the Australian cotton industry.Similarly, there has been little research conducted to identify whether cotton responds to partial rootzone drying and there is currently little understanding of theway in which DI and PRD strategies could be implemented commercially using LMIMs.This research carried out from 2002 to 2005 investigated the response of cotton to a range of PRD and deficit irrigation strategies for use under LMIMs. Assessment ofthe biochemical and physiological response of cotton to PRD and regulated deficit irrigation strategies was conducted under glasshouse conditions in Toowoomba, Qld.Field trials conducted under a commercial centre pivot and lateral move situated on the Darling Downs assessed the crop response, soil moisture movement, yield andgross production water use associated with the implementation of a range of PRD and deficit treatments. Modelling of rainfall probability and soil moisture movement were also undertaken to quantify constraints to the successful commercial implementation of irrigation management strategies such as PRD within theAustralian cotton industry.PRD applied to cotton grown in split-pot containers under glasshouse conditions was found to produce a biochemical response in the form of a four fold increase in xylemAbscisic Acid concentration. The application of alternated PRD strategies was generally found to reduce both vegetative (i.e. height, leaf area) and reproductive(i.e. fruiting sites) plant growth compared to Control treatments irrigated on both sides of the plant. Increasing the period between PRD alternations from 5 to 15days when the soil moisture potential in the wet root zone was maintained between 30 and 60 kPa also reduced the plant height and the number of fruiting sites.However, where the soil moisture in the wetted root zone was maintained at <3 kPa and alternation was based on the dry root zone moisture levels 16% (~350 kPa) and10% (>1500 kPa) there was no difference in the major plant growth indicators (i.e. height, fruiting branches, fruiting sites, leaf area) between the various alternatedPRD treatments. This suggests that the level of moisture availability in the wet root zone area is a key factor influencing water uptake and crop stress under alternatedPRD conditions.No significant difference in crop growth or yield was found as a result of the PRD treatments implemented under commercial field conditions. However, this may havebeen attributed to the inability to apply and maintain a sufficient soil moisture gradient across the root zone to successfully induce biochemical signalling from PRD. Practical limitations in the successful application of PRD in cotton production are attributed to the soil hydraulic properties, current irrigation practices (i.e. volumeand frequency of water applied) and the occurrence of in-season rainfall events. Rainfall probability and soil moisture modelling were used to evaluate the practical application of PRD within the Australian cotton industry. This work suggested thatthe creation of a soil moisture gradient across the plant root zone large enough to trigger a PRD response is most likely to be achieved on light textured soils located insemi-arid regions which experience minimal in-season rainfall events. However, the conditions are only met for a relatively small proportion of the current Australiancotton industry. Hence, it would seem that further research into the benefits of implementing PRD in cotton under LMIMs is not warranted.Regulated deficit irrigation applied under glasshouse conditions was found to have a controlling influence over partitioning between vegetative and reproductive growth.Improved physiological and gross production to water use benefits were measured as a result of deficit irrigation under field conditions and regulated deficit irrigationunder glasshouse conditions. Deficit irrigation (79% of predicted ET) under field conditions produced a 31.5% improvement in gross production water use index(GPWUI = Yield / Total water applied (rainfall, irrigation and stored soil moisture)) over commercial practice (i.e. applying 100% of predicted ET). However, thelargest benefits derived from deficit irrigation were associated with the management of crop agronomics (i.e. vegetative growth, retention rate and crop earliness) and the increased ability for capture of in-crop rainfall. Hence, deficit irrigation may provide substantial benefits for the cotton industry in terms of productivity of irrigation water applied as well as total water applied (irrigation, rainfall and soil moisture reserves).The ability to implement a suitable deficit irrigation strategy is regionally and seasonally dependent as the uncertainty over the timing of rainfall events andirrigation allocation both within and between seasons makes the optimal use of water resources difficult. Hence, future research should aim to enhance current cropproduction models to predict crop growth and response to a range of deficit irrigation treatments. Greater knowledge and adoption in the use of climatic predictors (suchas SOI) are required to improve the volume and timing of deficit irrigations applied. An economics framework should be developed which encompasses resource costs and constraints on a farm basis to enable the identification of optimal management practices based on the risk profiles of the various deficit irrigation strategies.Irrigation scheduling under LMIMs is also currently limited by the use of point scale soil moisture measurements (especially under low energy precision applicator LEPA) socks) and this may be improved by the use of plant based sensors.
33
Geremew, Eticha Birdo. "Modelling the soil water balance to improve irrigation management of traditional irrigation schemes in Ethiopia". Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-05242009-121531.
Testo completo
34
Ngaidé, Tidiane. "Socio-economic implications of irrigation systems in Mauritania the Boghé and Foum-Gleita irrigation projects /". [Madison : s.n.], 1986. http://catalog.hathitrust.org/api/volumes/oclc/15113431.html.
Testo completo
35
Patterson, Michelle M. "Irrigation and climate effects on selenium in the Kendrick Irrigation District, WY, and a bioremediation strategy". Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1992120371&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Testo completo
36
Derbala, Asaad Abdelkader Abdalla [Verfasser]. "Development and evaluation of mobile drip irrigation with center pivot irrigation machines / Asaad Abdelkader Abdalla Derbala". Braunschweig : Bundesforschungsanst. für Landwirtschaft, 2003. http://d-nb.info/996797408/34.
Testo completo
37
El, Chami Daniel <1979>. "Irrigation water management and policy on farm decision: The case study of the RENANA irrigation board". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3135/1/Final_Thesis.pdf.
Testo completo
38
El, Chami Daniel <1979>. "Irrigation water management and policy on farm decision: The case study of the RENANA irrigation board". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3135/.
Testo completo
39
Kazemi, Hossein V. "Estimating crop water requirements in south-central Kansas". Thesis, Kansas State University, 1985. http://hdl.handle.net/2097/9859.
Testo completo
40
Nicol, Lorraine, e University of Lethbridge Faculty of Arts and Science. "Irrigation water markets in Southern Alberta". Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/275.
Testo completoAbstract (sommario):
Irrigation is central to the functioning of the southern Alberta economy. Irrigation also uses a significant amount of what is expected to be an increasingly scarce resource: water. The Alberta government is embarking on a long-term water management strategy in which irrigation water management will be pivotal. The government is considering a range of economic instruments to assist in this management. One instrument already implemented is the ability of private irrigators and irrigators within irrigation districts to trade irrigation water rights on a temporary and permanent basis. This has established the foundation for water markets. The research presented in this thesis centers on establishing the characteristics of irrigation water markets in southern Alberta. The research also aims to determine whether the markets are behaving according to basic economic principles and whether they are supporting government's goals of increased water productivity, efficiency and conservation. The findings reveal that characteristics of irrigation water markets in southern Alberta. The research also aims to determine whether the markets are behaving according to basic economic principles and whether they are supporting government's goals of increased water productivity, efficiency and conservation. The findings reveal that characteristics of water markets in southern Alberta are very similar to markets elsewhere and the markets are behaving in a manner one would expect. However, markets are also creating activity that at one and the same time support and contradict government's water management goals. In addition, the small degree of market activity in general suggests that if government is relying on markets to contribute to these goals to any significant extent, it will need to create conditions that promote greater water market activity.x, 184 leaves : ill., maps ; 29 cm.
41
Agodzo, Sampson Kwaku. "Trickle irrigation using porous clay pot". Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.331989.
Testo completo
42
Dvorak, Gary John. "Economic analysis of irrigation pumping plants". Thesis, Kansas State University, 1985. http://hdl.handle.net/2097/9834.
Testo completo
43
Kuntz, Lauren B. "Wick irrigation systems for subsistence farming". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/83726.
Testo completoAbstract (sommario):
Thesis (S.B.)--Massachusetts Institute of Technology, Department of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-61).
Irrigation on small-scale farms has been noted as a key method to help lift subsistence farmers out of poverty. With water scarity growing around the globe and lack of access to electricity still prevalent in rural areas, the need to develop an energy efficient irrigation system that simultaneous limits wasted water while being low cost is essential. The possibility of using a wicking irrigation system that relies on the suction plants create for water to mitigate the pumping pressure is investigated. A theoretical model for such a system is developed for an acre sized wicking irrigation system, and the power and water efficiency is compared to a standard drip irrigation system. While the wicking irrigation system has a greater distribution of water delivery from the wicks than compared to the dripper system, a wicking system has the potential to operate at much lower power, with the possibility of even being a power source. If a direct coupling could be developed between the plant's roots and wick, eliminating the need for water to travel through the soil, the energy benefit of the wicking system would be even more dramatic.
by Lauren B. Kuntz.
S.B.
44
Siddeek, Fathima Zeena. "Water management for lowland rice irrigation". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71183.
Testo completoAbstract (sommario):
A procedure was developed to estimate optimum irrigation requirements for lowland rice cultivation in Southeast Asia. The procedure uses a water balance equation of semi-stochastic nature to maintain minimum desired water depths in paddy fields at the end of each irrigation period. The procedure estimates weekly pan evaporation (EV) and rainfall (RF) at different probability levels, which is then used to determine weekly irrigation requirements at different probability levels.
To illustrate the use of the method, the Kalawewa irrigation scheme in Sri Lanka was selected for demonstration purposes. Different transformations were applied to Rf and EV data in an attempt to normalize these variates and to obtain a unique distribution to describe their variations. Statistical analysis of weekly EV arid RF showed that the power transformation was best able to transform the weekly RF and EV data to normality.
Comparison of the use of the model and current system practices showed that a significant amount of water could be saved even when the system was operated at high probability levels (90% reliability). The irrigation water required when the system was operated at the 72% probability level was about 21% less than the amount required when the system was operated at 90% probability level during some weeks.
The EXTRAN flow routing model was used to simulate water flow in the upper reaches of the main canal system for varying discharges at the head gate each day. The simulated water depths were used to determine the gate settings required at the turnout structures to divert the desired amount of irrigation water into the turnout areas.
The flow simulation for the demonstration area, showed that it was not possible to regulate irrigation water from the main reservoir to meet daily demands at all the turnouts. This was due to the large distances between the regulating reservoir and turnouts that caused appreciable time lag for the flow to reach the turnouts farthest from the regulating reservoir.Ph. D.
45
Raza, Khalil. "Experimental Assessment of Photovoltaic Irrigation System". Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1411072971.
Testo completo
46
Rutland, Daniel C. "Evapotranspiration-based irrigation controllers in Florida". [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041310.
Testo completo
47
Holbrook, Gregory Martin. "The structure of an irrigation scheme". Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1002664.
Testo completoAbstract (sommario):
Faced with problems related to the sustainability and advisability of contemporary irrigation development in Africa, anthropologists have increasingly looked to economic and political explanations for the success or failure of those development schemes. Instead of seeking explanations in these isolated areas, this thesis has argued that irrigation development needs to be understood through relationships within and between politics, economics, social structure and culture. In order to uncover those interactions with regard to the Tyefu Irrigation Scheme in the southern African homeland of Ciskei, reference has been made, firstly, to the mechanisms underlying contemporary state expansion and secondly, to the interaction between external forces, structures and surface forms through time. Anthropological fieldwork techniques have been used to provide detailed descriptions of everyday communications within and between groups associated with the development. Ethnography allows implementation to be conceptualized in terms of the interaction between local level structures and structures associated with the planning and construction of irrigation development itself. When the effect of external forces on the interaction between structures and forms is then taken into account principles emerge that reflect local and historical transformations. These in turn suggest the form of contemporary state expansion in southern Africa, as well as its bearing on daily life on the rural periphery.
48
Mukherjee, Sushmita. "Integrated irrigation management model for deficit irrigation". Thesis, 2013. http://localhost:8080/iit/handle/2074/6588.
Testo completo
49
Hung, Chi-Chih, e 洪啓智. "Irrigation Efficiency Assessment of Furrow and Flooding Irrigations in Paddy Fields". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/55117710720820219673.
Testo completoAbstract (sommario):
碩士國立屏東科技大學
土木工程系所
102
Rice is one of the main crops cultivated in Taiwan, accounting for the majority cultivate area. The planted rice will increase water consumption following growing process. If the rice planting process can effectively reduce the amount of water consumption that can effectively improve the efficiency of agricultural water utilization. In this study, a sand box and a 3 m #westeur024# 5 m lysimeter, located in Irrigation Promotion Center, Taiwan Chia-Nan Irrigation Association, were tested for water saving efficiency of rice consumption. In field two irrigation methods, furrow irrigation and flooding irrigation, were compared the water saving efficiency as well as the assessment of rice production under the same water storage condition. The results shown that in sand box test water started to supply the furrow irrigation mode was able to reduce 30% water consumption when the water depth of midpoint was reduced to 1 cm. In the field lysimeter test, furrow irrigation was 30% water consumption less than flooding irrigation before rice heading period. During the rice heading period, although rice growth need large amount of water the furrow irrigation was 10% less than flooding irrigation. The rice root assessment shown the development of root was more gigantic root for furrow irrigation than flooding irrigation. Because the furrow irrigation was kept water inside the ditch the soil outside of ditch were leaked that conducive to the development of air exchange with the root. The longest rice root was 20 cm for flooding irrigation however it was up to 25 cm for furrow irrigation. For furrow irrigation the average rice production was 2.86 g per plant in the wet weight for furrow irrigation more than flooding irrigation.
50
Chuang, Chun-Fang, e 莊淳芳. "Application of Cluster Analysis on Irrigation Performance of Irrigation Associations". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/62674457676201185271.
Testo completoAbstract (sommario):
碩士國立嘉義大學
土木與水資源工程學系研究所
95
Though the mean rainfall at Taiwan reaches to 2515mm per year, but the water shortage seems to be the most troublesome problem due to the unpredictable pattern both on temporal and spatial distribution. Agricultural water occupies more than half of the total usable water at Taiwan, 71% of annual rainfall assigned to the agricultural sector at 2005 is the typical figure. The water demand increases gradually, due to the rapidly growth at population, economical activities and industrial reforming. Irrigation efficiency then becomes a very important issue to make the most benefit of water under the weather and topographical conditions. Cluster analysis is introduced here as a fundamental tool to classify the performance of irrigation at paddy filed for the irrigation associations at Taiwan. The author refines the factors proposed from ICID to evaluate the apparent performance of the 15 irrigation associations at Taiwan. Water balance, environment and economic are the factors to determine the dimentionless indices and the basic terms for clustering process. Sensitivity analysis is the second part to discuss the degree of influence among theses factors. The results of sensitivity analysis can be used as the reference base for water management on-farm and promoting the water allocation efficiency. The conclusion shows that there can be categorized into three groups for the irrigation associations based on the integrated performance index for the paddy operation. The group with higher index includes Tao-Yuan, Shih-Men, Chang-Hua and Chia-Nan associations. Pei-Kee association stays alone at the lower index group. The other associations perform at the middle range. The very first influence factor is economic index and the environment index plays the less significant contribution.