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Sample records for irrigation scheduling electronic

  1. Scheduling of Irrigation and Leaching Requirements

    Directory of Open Access Journals (Sweden)

    Amer Hassan Al-haddad

    2015-03-01

    Full Text Available Iraq depends mainly on Tigris and Euphrates Rivers to provide high percentage of agricultural water use for thousands years. At last years, Iraq is suffering from shortage in water resources due to global climate changes and unfair water politics of the neighboring countries, which affected the future of agriculture plans for irrigation, added to that the lack of developed systems of water management in the irrigation projects and improper allocation of irrigation water, which reduces water use efficiency and lead to losing irrigation water and decreasing in agricultural yield. This study aims at studying the usability of irrigation and leaching scheduling within the irrigating projects and putting a complete annual or seasonal irrigation program as a solution for the scarcity of irrigation water, the increase of irrigation efficiency, lessening the salinity in the projects and preparing an integral irrigation calendar through field measurements of soil physical properties and chemical for project selected and compared to the results of the irrigation scheduling and leaching with what is proposed by the designers. The process is accomplished by using a computer program which was designed by Water Resources Department at the University of Baghdad, with some modification to generalize it and made it applicable to various climatic zone and different soil types. Study area represented by large project located at the Tigris River, and this project was (Al-Amara irrigation project. Sufficient samples of project's soil were collected so as to identify soil physical and chemical properties and the salinity of soil and water as well as identifying the agrarian cycles virtually applied to this project. Finally, a comparison was conducted between the calculated water quantities and the suggested ones by the designers. The research results showed that using this kind of scheduling (previously prepared irrigation and leaching scheduling with its properties

  2. Computer-based irrigation scheduling for cotton crop

    International Nuclear Information System (INIS)

    Laghari, K.Q.; Memon, H.M.

    2008-01-01

    In this study a real time irrigation schedule for cotton crop has been tested using mehran model, a computer-based DDS (Decision Support System). The irrigation schedule was set on selected MAD (Management Allowable Depletion) and the current root depth position. The total 451 mm irrigation water applied to the crop field. The seasonal computed crop ET (Evapotranspiration) was estimated 421.32 mm and actual (ET/sub ca/) observed was 413 mm. The model over-estimated seasonal ET by only 1.94. WUE (Water Use Efficiency) for seed-cotton achieved 6.59 Kg (ha mm)/sup -1/. The statistical analysis (R/sup 2/=0.96, ARE%=2.00, T-1.17 and F=550.57) showed good performance of the model in simulated and observed ET values. The designed Mehran model is designed quite versatile for irrigation scheduling and can be successfully used as irrigation DSS tool for various crop types. (author)

  3. Irrigation scheduling with the neutron probe

    International Nuclear Information System (INIS)

    Travers, P.

    1987-01-01

    The operational theory of the neutron probe is briefly outlined and its application and uses discussed in relation to determination of soil compaction and irrigation scheduling. Graphic examples are given of alluvial soil moisture profiles and how this information can be used to improve trickle irrigation in vineyards. 3 refs., 7 figs

  4. Comparison of traditional and ET-based irrigation scheduling of surface-irrigated cotton in the arid southwestern USA

    Science.gov (United States)

    The use of irrigation scheduling tools to produce cotton under-surface irrigation in the arid southwesternUSA is minimal. In the State of Arizona, where traditional irrigation scheduling is the norm, producersuse an average of 1460 mm annually to grow a cotton crop. The purpose of this paper was to ...

  5. Scheduling irrigation for jujube ( Ziziphus jujuba Mill. ) | Zhang ...

    African Journals Online (AJOL)

    This study was performed to select suitable indicator for scheduling the irrigation of jujube (Ziziphus jujuba Mill.) grown in the Loess Plateau. The relationships between plant-based indicators and soil matrix potential as well as meteorological factors of jujube under deficit irrigation compared with well irrigation were ...

  6. Water requirement and irrigation schedule for tomato in northern guinea savanna zone, Nigeria

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    Ibraheem Alhassan

    2015-06-01

    Full Text Available Assessment of water requirement and irrigation schedule for tomato with the support of FAO-CROPWAT simulation model was carried out for Yola, Nigeria with the aim of planning irrigation schedules for tomato and develop recommendations for improve irrigation practices. The climatic data for 2012/2013 and soil properties of the study area were input into the program. Tomato crop properties were updated by the FAO data and three irrigation intervals were tested (7 and 10 days irrigation intervals and irrigation schedule of 10 days interval during initial and development stage and 6 days interval at mid and late season stages of tomato crop. The simulated results analysis for tomato according to the irrigation schedule showed that highest yield reduction of 16.2% was recorded with 10 days irrigation interval treatment and the least of 0.4% with irrigation interval of 10 days at first two growth stages and 6 days at last two stages. FAO-CROPWAT 8.0 can be used in planning proper irrigation schedule for tomato in Yola, Nigeria.

  7. New Approaches to Irrigation Scheduling of Vegetables

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    Michael D. Cahn

    2017-04-01

    Full Text Available Using evapotranspiration (ET data for scheduling irrigations on vegetable farms is challenging due to imprecise crop coefficients, time consuming computations, and the need to simultaneously manage many fields. Meanwhile, the adoption of soil moisture monitoring in vegetables has historically been limited by sensor accuracy and cost, as well as labor required for installation, removal, and collection of readings. With recent improvements in sensor technology, public weather-station networks, satellite and aerial imaging, wireless communications, and cloud computing, many of the difficulties in using ET data and soil moisture sensors for irrigation scheduling of vegetables can now be addressed. Web and smartphone applications have been developed that automate many of the calculations involved in ET-based irrigation scheduling. Soil moisture sensor data can be collected through wireless networks and accessed using web browser or smartphone apps. Energy balance methods of crop ET estimation, such as eddy covariance and Bowen ratio, provide research options for further developing and evaluating crop coefficient guidelines of vegetables, while recent advancements in surface renewal instrumentation have led to a relatively low-cost tool for monitoring crop water requirement in commercial farms. Remote sensing of crops using satellite, manned aircraft, and UAV platforms may also provide useful tools for vegetable growers to evaluate crop development, plant stress, water consumption, and irrigation system performance.

  8. IRRIGATION SCHEDULING CALCULATOR (ISC TO IMPROVE WATER MANAGEMENT ON FIELD LEVEL IN EGYPT

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    Samiha Abou El-Fetouh Hamed Ouda

    2017-10-01

    Full Text Available The developed model is MS excel sheet called “Irrigation Scheduling Calculator, ISC”. The model requires to input daily weather data to calculate daily evapotranspiration using Penman-Monteith equation. The model calculates water depletion from the root zone to determine when to irrigate and how much water should be applied. The charge from irrigation pump is used to calculate how many hours should the farmer run the pump to deliver the needed amount of water. ISC model was used to developed irrigation schedule for wheat and maize planted in El-Gharbia governorate. The developed schedules were compared to the actual schedules for both crops. Furthermore, CropSyst model was calibrated for both crops and run using the developed schedules by ISC model. The simulation results indicated that the calculated irrigation amount by ISC model for wheat was lower than actual schedule by 6.0 mm. Furthermore, the simulated wheat productivity by CropSyst was higher than measured grain and biological by 2%. Similarly, the calculated applied irrigation amount by ISC model for maize was lower than actual schedule by 79.0 mm and the productivity was not changed.

  9. Irrigation Scheduling for Green Bell Peppers Using Capacitance Soil Moisture Sensors

    NARCIS (Netherlands)

    Zotarelli, L.; Dukes, M.D.; Scholberg, J.M.S.; Femminella, K.; Munoz-Carpena, R.

    2011-01-01

    Vegetable production areas are intensively managed with high inputs of fertilizer and irrigation. The objectives of this study were to evaluate the interaction between N-fertilizer rates and irrigation scheduling using soil moisture sensor irrigation controllers (SMS) on yield, irrigation water use

  10. Year-Round Irrigation Schedule for a Tomato–Maize Rotation System in Reservoir-Based Irrigation Schemes in Ghana

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    Ephraim Sekyi-Annan

    2018-05-01

    Full Text Available Improving irrigation management in semi-arid regions of Sub-Saharan Africa is crucial to respond to increasing variability in rainfall and overcome deficits in current irrigation schemes. In small-scale and medium-scale reservoir-based irrigation schemes in the Upper East region of Ghana, we explored options for improving the traditional, dry season irrigation practices and assessed the potential for supplemental irrigation in the rainy season. The AquaCrop model was used to (i assess current water management in the typical tomato-maize rotational system; (ii develop an improved irrigation schedule for dry season cultivation of tomato; and (iii determine the requirement for supplemental irrigation of maize in the rainy season under different climate scenarios. The improved irrigation schedule for dry season tomato cultivation would result in a water saving of 130–1325 mm compared to traditional irrigation practices, accompanied by approximately a 4–14% increase in tomato yield. The supplemental irrigation of maize would require 107–126 mm of water in periods of low rainfall and frequent dry spells, and 88–105 mm in periods of high rainfall and rare dry spells. Therefore, year-round irrigated crop production may be feasible, using water saved during dry season tomato cultivation for supplemental irrigation of maize in the rainy season.

  11. Irrigation scheduling using soil moisture sensors

    Science.gov (United States)

    Soil moisture sensors were evaluated and used for irrigation scheduling in humid region. Soil moisture sensors were installed in soil at depths of 15cm, 30cm, and 61cm belowground. Soil volumetric water content was automatically measured by the sensors in a time interval of an hour during the crop g...

  12. Enhancing Adoption of Irrigation Scheduling to Sustain the Viability of Fruit and Nut Crops in California

    Science.gov (United States)

    Fulton, A.; Snyder, R.; Hillyer, C.; English, M.; Sanden, B.; Munk, D.

    2012-04-01

    Enhancing Adoption of Irrigation Scheduling to Sustain the Viability of Fruit and Nut Crops in California Allan Fulton, Richard Snyder, Charles Hillyer, Marshall English, Blake Sanden, and Dan Munk Adoption of scientific methods to decide when to irrigate and how much water to apply to a crop has increased over the last three decades in California. In 1988, less than 4.3 percent of US farmers employed some type of science-based technique to assist in making irrigation scheduling decisions (USDA, 1995). An ongoing survey in California, representing an industry irrigating nearly 0.4 million planted almond hectares, indicates adoption rates ranging from 38 to 55 percent of either crop evapotranspiration (ETc), soil moisture monitoring, plant water status, or some combination of these irrigation scheduling techniques to assist with making irrigation management decisions (California Almond Board, 2011). High capital investment to establish fruit and nut crops, sensitivity to over and under-irrigation on crop performance and longevity, and increasing costs and competition for water have all contributed to increased adoption of scientific irrigation scheduling methods. These trends in adoption are encouraging and more opportunities exist to develop improved irrigation scheduling tools, especially computer decision-making models. In 2009 and 2010, an "On-line Irrigation Scheduling Advisory Service" (OISO, 2012), also referred to as Online Irrigation Management (IMO), was used and evaluated in commercial walnut, almond, and French prune orchards in the northern Sacramento Valley of California. This specific model has many features described as the "Next Generation of Irrigation Schedulers" (Hillyer, 2010). While conventional irrigation management involves simply irrigating as needed to avoid crop stress, this IMO is designed to control crop stress, which requires: (i) precise control of crop water availability (rather than controlling applied water); (ii) quantifying crop

  13. Development of an irrigation scheduling software based on model predicted crop water stress

    Science.gov (United States)

    Modern irrigation scheduling methods are generally based on sensor-monitored soil moisture regimes rather than crop water stress which is difficult to measure in real-time, but can be computed using agricultural system models. In this study, an irrigation scheduling software based on RZWQM2 model pr...

  14. Improved irrigation scheduling for pear-jujube trees based on trunk ...

    African Journals Online (AJOL)

    A suitable indicator for scheduling pear-jujube (Ziziphus jujuba Mill.) irrigation in China was developed based on trunk diameter fluctuations (TDF). Parameters derived from TDF responses to variations in soil matrix potential (Ψsoil) were compared under deficit and well irrigation. Maximum daily shrinkage (MDS) increased ...

  15. Soil capacitance sensors and stem dendrometers. Useful tools for irrigation scheduling of commercial orchards?

    Energy Technology Data Exchange (ETDEWEB)

    Bonet, L.; Ferrer, P.; Castel, J. R.; Intrigliolo, D. S.

    2010-07-01

    Irrigation scheduling is often performed based on a soil water balance, where orchard evapotranspiration is estimated using the reference evapotranspiration (ETo) times the crop coefficient (Kc). This procedure, despite being widely spread, has some uncertainties. Because of this, plant and soil water status monitoring could be alternatively or complementarity used to schedule irrigation. The usefulness of capacitance probes was evaluated during several seasons in large irrigation districts where irrigation practices were changed over years from the ETo * Kc model to the analysis of soil water status trend. This area corresponds to drip irrigated orchards planted with citrus, peach, nectarine and persimmon. Around 25% less irrigation was applied with no substantial yield penalty when the information provided by capacitance probes was correctly applied for irrigation management. On the other hand, the usefulness of stem dendrometers for continuously monitoring plant water status was evaluated in a young plum experimental orchard. Over two years, irrigation was scheduled using exclusively trunk shrinkage via the signal intensity approach by means of a baseline equation previously obtained in the orchard. Results showed that it was not always possible to schedule irrigation based on the trunk shrinkage signal intensity due to the temporal changes in the reference values that occurred as trees aged. Overall, results obtained are discussed in terms of the possible extrapolation at field level of both capacitance probes and stem dendrometers. Advantages and drawbacks of each technique are analyzed and discussed. (Author) 34 refs.

  16. Soil water sensors for irrigation scheduling:Can they deliver a management allowed depletion?

    Science.gov (United States)

    Soil water sensors are widely marketed in the farming sector as aids for irrigation scheduling. Sensors report either volumetric water content (theta-v, m**3 m**-3) or soil water potential, with theta-v sensors being by far the most common. To obtain yield and quality goals, irrigations are schedule...

  17. Evaluating irrigation scheduling of hydroponic tomato in Navarra, Spain

    NARCIS (Netherlands)

    Lizarraga, H.J.; Boesveld, H.; Huibers, F.P.; Robles, H.

    2003-01-01

    The correct supply of water and nutrients is important in hydroponic growing systems in order to use water efficiently, avoid stress situations, and control production. The present study was conducted to evaluate two irrigation scheduling techniques for hydroponic tomato production in Navarra,

  18. Nuclear techniques to assess irrigation schedules for field crops. Results of a co-ordinated research programme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This TECDOC summarizes the results of a Co-ordinated Research Programme on The Use of Nuclear and Related Techniques in Assessment of Irrigation Schedules of Field Crops to Increase Effective Use of Water in Irrigation Projects. The programme was carried out between 1990 and 1995 through the technical co-ordination of the Soil Fertility, Irrigation and Crop Production Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture of the International Atomic Energy Agency. Fourteen Member States of the IAEA and FAO carried out a series of field experiments aimed at improving irrigation water use efficiency through a type of irrigation scheduling known as deficit irrigation. Refs, figs, tabs.

  19. Nuclear techniques to assess irrigation schedules for field crops. Results of a co-ordinated research programme

    International Nuclear Information System (INIS)

    1996-06-01

    This TECDOC summarizes the results of a Co-ordinated Research Programme on The Use of Nuclear and Related Techniques in Assessment of Irrigation Schedules of Field Crops to Increase Effective Use of Water in Irrigation Projects. The programme was carried out between 1990 and 1995 through the technical co-ordination of the Soil Fertility, Irrigation and Crop Production Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture of the International Atomic Energy Agency. Fourteen Member States of the IAEA and FAO carried out a series of field experiments aimed at improving irrigation water use efficiency through a type of irrigation scheduling known as deficit irrigation. Refs, figs, tabs

  20. Irrigation scheduling of spring wheat using infrared thermometry

    International Nuclear Information System (INIS)

    Stegman, E.C.; Soderlund, M.G.

    1989-01-01

    Irrigation scheduling for spring wheat requires information on different irrigation timing methods. Irrigation timing based on allowable root zone available water depletion and selected crop water stress index (CWSI) thresholds were evaluated in terms of their effect on spring wheat yield. A field study was conducted at Oakes, North Dakota in 1987 and 1988 on a Maddock sandy loam soil with two varieties of spring wheat (Marshall and Wheaton) using a split plot randomized block design. Irrigation was metered to each plot using trickle irrigation tubing. Neutron soil water measurements along with a water balance model were used to time irrigations that were based on different allowed root zone depletions. Infrared thermometer sensors (IRT) were used to measure in situ canopy temperatures and along with measured climatic information were used to time irrigations using the CWSI approach. Additionally, crop phenological stages and final grain yield were measured. The non-water-stressed baselines necessary for the CWSI differed between the two seasons but were similar to those from previous studies. The CWSI methods were feasible from the Feekes scale S4 (beginning pseudo-stem) to S11.2 (mealy ripe). Minimal yield reductions were observed using the CWSI method for thresholds less than 0.4-0.5 during this period. Minimal yield reductions were observed by maintaining the root zone allowable depletion below 50%. The grain yield-evapotranspiration (ET) relationship was linear in both years but with different slopes and intercepts. When analyzed on a relative basis to maximum ET (ETm), a single relationship fit both years’ data with a yield sensitivity factor of 1.58. Irrigations timed at CWSI = 0.5 reduced seasonal water application by 18% relative to treatments irrigated at CWSI = 0.2. (author)

  1. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    International Nuclear Information System (INIS)

    Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

    2016-01-01

    Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  2. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

    2016-07-01

    Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  3. Infra-red thermography for detecting drought in agricultural crops and scheduling irrigation

    Directory of Open Access Journals (Sweden)

    Petrović Ivana

    2016-01-01

    Full Text Available The use of thermal imaging is a fast growing and potentially important tool in various fields of agriculture. The technology visually identified the rise of temperature in crop canopy which occurs as a result of drought and allows the precise scheduling of crop irrigation. The aim of presenting paper was to demonstrate the application of these techniques on potato plants and to point out on the necessity of irrigation for potato sustainable and economically justified production.

  4. Use of infrared thermometer technique in irrigation scheduling of pomegranate (Punica granatum L. plant

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    Begüm TEKELİOĞLU

    2017-06-01

    Full Text Available The main objectives of this study are to assess crop water stress index (CWSI and to determine irrigation schedule of pomegranate using infrared thermometer technique. Treatments with three replications were irrigated every three and six days intervals, as much as 0.50 (S1, 0.75 (S2, 1.00 (S3, and 1.25 (S4 of Class A pan evaporation. Additionally, an unirrigated plot was also formed. The equations obtained for non-water stress baseline is Tc-Ta=0.645VPD-4.338. The equation of full water stressed upper baseline obtained from data taken from branches of pomegranate plant cut in different days is given by Tc-Ta= 0.0489VPD+2.8734. According to the results obtained, it is concluded that infrared thermometer can be used for irrigation scheduling of the pomegranate plants in Antalya conditions. When using this technique in Antalya conditions, it is suggested to keep the seasonal mean CWSI value approximately 0.12 and the index value of 0.40 can be used to start the irrigation. Additionally, it is suggested that the amount of irrigation can be determined as much as the amount of evaporation measured until the index value reaches 0.40.

  5. Stress Coefficients for Soil Water Balance Combined with Water Stress Indicators for Irrigation Scheduling of Woody Crops

    Directory of Open Access Journals (Sweden)

    Maria Isabel Ferreira

    2017-06-01

    Full Text Available There are several causes for the failure of empirical models to estimate soil water depletion and to calculate irrigation depths, and the problem is particularly critical in tall, uneven, deficit irrigated (DI crops in Mediterranean climates. Locally measured indicators that quantify water status are useful for addressing those causes and providing feed-back information for improving the adequacy of simple models. Because of their high aerodynamic resistance, the canopy conductance of woody crops is an important factor in determining evapotranspiration (ET, and accurate stress coefficient (Ks values are needed to quantify the impact of stomatal closure on ET. A brief overview of basic general principles for irrigation scheduling is presented with emphasis on DI applications that require Ks modelling. The limitations of existing technology related to scheduling of woody crops are discussed, including the shortcomings of plant-based approaches. In relation to soil water deficit and/or predawn leaf water potential, several woody crop Ks functions are presented in a secondary analysis. Whenever the total and readily available water data were available, a simple Ks model was tested. The ultimate aim of this discussion is to illustrate the central concept: that a combination of simple ET models and water stress indicators is required for scheduling irrigation of deep-rooted woody crops.

  6. An integrated modeling framework for real-time irrigation scheduling: the benefit of spectroscopy and weather forecasts

    Science.gov (United States)

    Brook, Anna; Polinova, Maria; Housh, Mashor

    2016-04-01

    Agriculture and agricultural landscapes are increasingly under pressure to meet the demands of a constantly increasing human population and globally changing food patterns. At the same time, there is rising concern that climate change and food security will harm agriculture in many regions of the world (Nelson et al., 2009). Facing those treats, majority of Mediterranean countries had chosen irrigated agriculture. For crop plants water is one of the most important inputs, as it is responsible for crop growth, production and it ensures the efficiency of other inputs (e.g. seeds, fertilizers and pesticide) but its use is in competition with other local sectors (e.g. industry, urban human use). Thus, well-timed availability of water is vital to agriculture for ensured yields. The increasing demand for irrigation has necessitated the need for optimal irrigation scheduling techniques that coordinate the timing and amount of irrigation to optimally manage the water use in agriculture systems. The irrigation scheduling problem can be challenging as farmers try to deal with different conflicting objectives of maximizing their yield while minimizing irrigation water use. Another challenge in the irrigation scheduling problem is attributed to the uncertain factors involved in the plant growth process during the growing season. Most notable, the climatic factors such as evapotranspiration and rainfall, these uncertain factors add a third objective to the farmer perspective, namely, minimizing the risk associated with these uncertain factors. Nevertheless, advancements in weather forecasting reduced the uncertainty level associated with future climatic data. Thus, climatic forecasts can be reliably employed to guide optimal irrigation schedule scheme when coupled with stochastic optimization models (Housh et al., 2012). Many studies have concluded that optimal irrigation decisions can provide substantial economic value over conventional irrigation decisions (Wang and Cai 2009

  7. Evaluation of a New Mexico Landrace and Two Commercial Chile (Capsicum annuum Cultivars under Four Furrow Irrigation Schedules

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    Israel Joukhadar

    2018-02-01

    Full Text Available Commercial and landrace chile (Capsicum annuum cultivars are cultivated under furrow irrigation systems in Northern New Mexico. Yield and physiological differences between commercial and landrace chile cultivars under furrow irrigation systems have not been evaluated. In 2011 and 2012 two commercial chiles, ‘Sandia’ and ‘NuMex Big Jim’, with one landrace chile, ‘Chimayo’, were evaluated under four irrigation schedules, with irrigation once every 7, 9, 11, and 13-days. These four schedules represent possible water availability for farmers in Northern New Mexico. In 2011 there were inconsistent yield patterns; fresh red chile yield of ‘Chimayo’ at the seven-day interval was 90% more than at the nine-day interval. ‘Sandia’ had 138% better yields at the seven- than at the nine-day interval. ‘Chimayo’ fresh green chile yields at the nine-day interval were 47% better than the seven-day interval. ‘NuMex Big Jim’ fresh green yields were 40% greater at the seven-day interval than the 13-day interval. In 2012 no yield components were statistically different for cultivars across irrigation intervals. This data shows commercial green and landrace chile cultivars can be furrow irrigated as water becomes available on 7, 9, 11, or 13-day intervals with no yield effect.

  8. Behaviour Of Saline Irrigation Water Components In Pakistani Barley And Calcareous Soil Under Scheduling Irrigation Using Neutron Scattering Technique

    International Nuclear Information System (INIS)

    RIZK, M.A.

    2010-01-01

    This study aims to investigate the behaviour of cation uptake by Pakistani barley (genotype PK-30163) as affected by saline irrigation water, as well as cation distribution within the soil profile. This experiment was carried out at Soil and Water Research Department, Nuclear Research Centre, Atomic Energy Authority, Inshas, Egypt. The soil was transferred from Wadi Sudr (South Sinai, Egypt). It is salted affected soil (calcareous soil, EC = 4.3 dS/m) and was irrigated using ground water irrigation (12.5 dS/m). Nine used lysimeters were irrigated with three artificial saline water (0.3, 4 and 8 dS/m) using drip irrigation system. The irrigation schedule was carried out using neutron scattering technique according to the hydro physical properties of the soil. Pakistani barley (halophytic plant) was used to remove salts from the soil especially sodium cations. The cation uptake and cation distribution (Na, K, Ca, Mg) within the soil profile were studied.The data indicated that roots of barley collected within 0-15 cm layer showed high cation uptake that made the salt concentrations in this layer low. Sodium uptake ratio was 43, 37 and 47% from total cation uptake by using fresh water (0.3 dS/m), 4 and 8 dS/m, respectively. The maximum uptake for Na, K, Ca and Mg was 20.51, 19.13, 3.98 and 12.81 g/lys at 5.69, 3.05, 6.56 and 4.15 dS/m, respectively. It was found that Pakistani barley preferred Mg uptake rather than Ca uptake.

  9. Effects of deficit drip-irrigation scheduling regimes with saline water on pepper yield, water productivity and soil salinity under arid conditions of Tunisia

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-12-01

    Full Text Available A two-year study was carried out in order to assess the effects of different irrigation scheduling regimes with saline water on soil salinity, yield and water productivity of pepper under actual commercial-farming conditions in the arid region of Tunisia. Pepper was grown on a sandy soil and drip-irrigated with water having an ECi of 3.6 dS/m. Irrigation treatments consisted in water replacements of accumulated ETc at levels of 100% (FI, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in the control treatment (FI is depleted, deficit irrigation during ripening stage (FI-MDI60 and farmer method corresponding to irrigation practices implemented by the local farmers (FM. Results on pepper yield and soil salinity are globally consistent between the two-year experiments and shows significant difference between irrigation regimes. Higher soil salinity was maintained over the two seasons, 2008 and 2009, with DI-60 and FM treatments than FI. FI-MDI60 and DI-80 treatments resulted also in low ECe values. Highest yields for both years were obtained under FI (22.3 and 24.4 t/ha although we didn’t find significant differences with the regulated deficit irrigation treatment (FI-DI60. However, the DI-80 and DI-60 treatments caused significant reductions in pepper yields through a reduction in fruits number/m² and average fruit weight in comparison with FI treatment. The FM increased soil salinity and caused significant reductions in yield with 14 to 43%, 12 to 39% more irrigation water use than FI, FI-MDI60 and DI-80 treatments, respectively, in 2008 and 2009. Yields for all irrigation treatments were higher in the second year compared to the first year. Water productivity (WP values reflected this difference and varied between 2.31 and 5.49 kg/m3. The WP was found to vary significantly among treatments, where the highest and the lowest values were observed for DI-60 treatment and FM, respectively. FI treatment provides

  10. Influence of crop load on almond tree water status and its importance in irrigation scheduling

    Science.gov (United States)

    Puerto Conesa, Pablo; Domingo Miguel, Rafael; Torres Sánchez, Roque; Pérez Pastor, Alejandro

    2014-05-01

    In the Mediterranean area water is the main factor limiting crop production and therefore irrigation is essential to achieve economically viable yields. One of the fundamental techniques to ensure that irrigation water is managed efficiently with maximum productivity and minimum environmental impact is irrigation scheduling. The fact that the plant water status integrates atmospheric demand and soil water content conditions encourages the use of plant-based water status indicators. Some researchers have successfully scheduled irrigation in certain fruit trees by maintaining the maximum daily trunk diameter shrinkage (MDS) signal intensity at threshold values to generate (or not) water stress. However MDS not only depends on the climate and soil water content, but may be affected by tree factors such as age, size, phenological stage and fruit load. There is therefore a need to quantify the influence of these factors on MDS. The main objective of this work was to study the effects of crop load on tree water relations for scheduling purposes. We particularly focused on MDS vs VPD10-15 (mean air vapor pressure deficit during the period 10.00-15.00 h solar time) for different loads and phenological phases under non-limiting soil water conditions. The experiment was carried out in 2011 in a 1 ha plot in SE Spain with almond trees (Prunus dulcis (Mill.) D.A. Webb cv. 'Marta'). Three crop load treatments were studied according to three crop load levels, i) T100, high crop load, characteristic crop load, ii) T50, medium crop load, in which 50% of the fruits were removed and iii) T0, practically without fruits. Fruits were manually thinned. Each treatment, randomly distributed in blocks, was run in triplicate. Plant water status was assessed from midday stem water potential (Ψs), MDS, daily trunk growth rate (TGR), leaf turgor potential Ψp, fruit water potential (Ψf), stomatal conductance (gs) and photosynthesis (Pn) and transpiration rates (E). Yield, pruning weights and

  11. Wireless sensor networks for irrigation management

    Science.gov (United States)

    Sustaining an adequate food supply for the world's population will require advancements in irrigation technology and improved irrigation management. Site-specific irrigation and automatic irrigation scheduling are examples of strategies to deal with declining arable land and limited fresh water reso...

  12. Technical descriptions of ten irrigation technologies for conserving energy

    Energy Technology Data Exchange (ETDEWEB)

    Harrer, B.J.; Wilfert, G.L.

    1983-05-01

    Technical description of ten technologies which were researched to save energy in irrigated agriculture are presented. These technologies are: well design and development ground water supply system optimization, column and pump redesign, variable-speed pumping, pipe network optimization, reduced-pressure center-pivot systems, low-energy precision application, automated gated-pipe system, computerized irrigation scheduling, and instrumented irrigation scheduling. (MHR)

  13. Effect of integrated plant nutrition and irrigation scheduling on yield and yield components of maize (zea mays l.)

    International Nuclear Information System (INIS)

    Randhawa, M.S.; Maqsood, M.; Wajid, S.A.; Haq, A.U.

    2012-01-01

    Effect of three irrigation schedules (4-6 irrigations) and seven integrated plant nutrition levels (control, 125-60-62 kg N-P/sub 2/O/sub 5/-K/sub 2/O ha/sup -1/, 125-60-62 kg N-P/sub 2/O/sub 5/--K/sub 2/O ha/sup -1/ + Farmyard manure at the rate 10 t ha/sup -1/, 125-60-62 kg N-P/sub 2/O/sub 5/-K/sub 2/O ha/sup -1/ + Farm yard manure at the rate 15 t ha-1, 250-120-125 kg N-P/sub 2/O/sub 5/--K/sub 2/O ha-1, 250-120-125 kg N-P/sub 2/O/sub 5/ -K/sub 2/O ha/sup -1/ + Farmyard manure at the rate 10 t ha-1 and 250-120-125 kg N-P/sub 2/O/sub 5/--K/sub 2/O ha/sup -1/ + Farmyard manure at the rate 15 t ha/sup -1/) on grain yield and its components in maize were studied during 2009 and 2010. Plant height, number of cobs plant-1, number of grain rows cob-1, number of grains cob-1, 1000-grain weight, grain weight cob-1, grain yield, stover yield and biological yield were significantly affected by irrigation schedules and integrated plant nutrition levels during both years. The crop applied with six irrigations and fertilized by integrated application of chemical fertilizers (250-120-125 kg N-P/sub 2/O/sub 5/--K/sub 2/O ha/sup -1/) and farmyard manure (15 t ha/sup -1/) produced the highest grain yield of 8.47 t ha/sup -1/ and 8.22 t ha/sup -1/ during 2009 and 2010, respectively. (author)

  14. Estratégias de manejo de água em caupi irrigado Strategies of irrigation scheduling in cowpea

    Directory of Open Access Journals (Sweden)

    Rubens Sonsol Gondim

    2000-04-01

    Full Text Available Este trabalho foi conduzido no período de setembro a dezembro de 1997, numa área irrigada da Fazenda Experimental do Vale do Curu, pertencente à Universidade Federal do Ceará, no município de Pentecoste, CE, localizada a 100 km de Fortaleza. O objetivo do experimento foi avaliar a utilização do tensiômetro de mercúrio, do Tanque Classe A e da equação de Hargreaves, na determinação da lâmina de água a ser aplicada na irrigação. O delineamento foi inteiramente casualizado, com três tratamentos e quatro repetições, enquanto os tratamentos foram representados pelos três diferentes métodos de estimação citados, de quando e quanto irrigar (Tratamento 1 - Tensiômetro; Tratamento 2 - Tanque Classe A e Tratamento 3 - equação de Hargreaves e a cultura utilizada foi o caupi (Vigna unguiculata (L. Walp para consumo em estado verde, cultivar João Paulo II, no espaçamento de 0,90 x 0,40 m, com duas plantas por cova, irrigada por aspersão convencional. A análise dos resultados constatou uma economia de água no tratamento 1, de 28 e 23%, em relação aos tratamentos 2 e 3, respectivamente, e também evidenciou a inexistência de diferenças significativas entre as produtividades alcançadas em todos os tratamentos. O tensiômetro pode ser indicado como instrumento de racionalização do uso da água em irrigação.A field study was conducted from September to December 1997 at the Federal University of Ceará Experimental Farm in Pentecoste, Brazil. The irrigation scheduling was based on a tensiometer, Class A pan evaporation and Hargreaves equation. The purpose of the research was to evaluate the three treatments (Treatment 1 - tensiometer, Treatment 2 - pan evaporation and Treatment 3 - Hargreaves equation with four replications in a completely randomized design. Sprinkler irrigated cowpea (Vigna unguiculata (L. Walp, cultivar João Paulo II for fresh consumption was grown on the experimental area. Plants were spaced at 0.90 x 0

  15. Integrating Growth Stage Deficit Irrigation into a Process Based Crop Model

    Science.gov (United States)

    Lopez, Jose R.; Winter, Jonathan M.; Elliott, Joshua; Ruane, Alex C.; Porter, Cheryl; Hoogenboom, Gerrit

    2017-01-01

    Current rates of agricultural water use are unsustainable in many regions, creating an urgent need to identify improved irrigation strategies for water limited areas. Crop models can be used to quantify plant water requirements, predict the impact of water shortages on yield, and calculate water productivity (WP) to link water availability and crop yields for economic analyses. Many simulations of crop growth and development, especially in regional and global assessments, rely on automatic irrigation algorithms to estimate irrigation dates and amounts. However, these algorithms are not well suited for water limited regions because they have simplistic irrigation rules, such as a single soil-moisture based threshold, and assume unlimited water. To address this constraint, a new modeling framework to simulate agricultural production in water limited areas was developed. The framework consists of a new automatic irrigation algorithm for the simulation of growth stage based deficit irrigation under limited seasonal water availability; and optimization of growth stage specific parameters. The new automatic irrigation algorithm was used to simulate maize and soybean in Gainesville, Florida, and first used to evaluate the sensitivity of maize and soybean simulations to irrigation at different growth stages and then to test the hypothesis that water productivity calculated using simplistic irrigation rules underestimates WP. In the first experiment, the effect of irrigating at specific growth stages on yield and irrigation water use efficiency (IWUE) in maize and soybean was evaluated. In the reproductive stages, IWUE tended to be higher than in the vegetative stages (e.g. IWUE was 18% higher than the well watered treatment when irrigating only during R3 in soybean), and when rainfall events were less frequent. In the second experiment, water productivity (WP) was significantly greater with optimized irrigation schedules compared to non-optimized irrigation schedules in

  16. Gain-P: A new strategy to increase furrow irrigation efficiency

    International Nuclear Information System (INIS)

    Schmitz, G.H.; Wohling, T.; Paly, M. D.; Schutze, N.

    2007-01-01

    The new methodology GAIN-P combines Genetic Algorithms, Artificial Intelligence techniques and rigorous Process modeling for substantially improving irrigation efficiency. The new strategy simultaneously identifies optimal values of both scheduling and irrigation parameters for an entire growing season and can be applied to irrigation systems with adequate or deficit water supply. In this contribution, GAIN-P is applied to furrow irrigation tackling the more difficult subject of the more effective deficit irrigation. A physically -based hydrodynamic irrigation model is iteratively coupled with a 2D subsurface flow model for generating a database containing all realistically feasible scenarios of water application in furrow irrigation. It is used for training a problem-adapted artificial neural network based on self-organized maps, which in turn portrays the inverse solution of the hydrodynamic furrow irrigation model and thus enormously speeds up the overall performance of the complete optimization tool. Global optimization with genetic algorithm finds the schedule with maximum crop yield for the given water volume. The impact of different irrigation schedules on crop yield is calculated by the coupled furrow irrigation model which also simulates soil evaporation, precipitation and root water uptake by the plants over the whole growing seasons, as well as crop growth and yield. First results with the new optimization strategy show that GAIN-P has a high potential to increase irrigation efficiency. (author)

  17. Conserving energy through new irrigation technologies. Technical briefing report

    Energy Technology Data Exchange (ETDEWEB)

    1982-07-01

    The benefits and applications of five irrigation technologies are explored: mobile drop-tube irrigation, computerized scheduling, reduced-pressure center pivots, well design and development, and automated gated-pipe systems. Perhaps the most promising of the new irrigation technologies is the low-energy, precision-application (LEPA) system. This mobile system used one-half the energy of conventional sprinkler systems and distributes water with greater efficiency through a series of low-pressure drop tubes suspended above the crop. Computerized methods of irrigation scheduling have been developed to help farmers conserve water and energy. Special computer programs determine when a crop needs water and how much to apply for optimal plant growth, thus preventing the unnecessary costs of pumping more water than the crop needs. Field test results show that replacing traditional scheduling methods of irrigation with computerized scheduling can reduce energy and water use by as much as 35%. The irrigation industry is actively promoting reduced-pressure water application methods, particularly for center-pivot systems. Reduced-pressure systems expend less energy but produce the same crop yields as conventional high-pressure systems, as long as excessive water runoff does not occur. If well design and development techniques are applied when a well is drilled into an unconsolidated acquifer, the well's life expectancy, as well as its operating efficiency, can increase, the later by as much as 40%.

  18. Optimal model-based deficit irrigation scheduling using AquaCrop: a simulation study with cotton, potato and tomato

    DEFF Research Database (Denmark)

    Linker, Raphael; Ioslovich, Ilya; Sylaios, Georgios

    2016-01-01

    -smooth behavior of the objective function and the fact that it involves multiple integer variables. We developed an optimization scheme for generating sub-optimal irrigation schedules that take implicitly into account the response of the crop to water stress, and used these as initial guesses for a full......Water shortage is the main limiting factor for agricultural productivity in many countries and improving water use efficiency in agriculture has been the focus of numerous studies. The usual approach to limit water consumption in agriculture is to apply water quotas and in such a situation farmers...... variables are the irrigation amounts for each day of the season. The objective function is the expected yield calculated with the use of a model. In the present work we solved this optimization problem for three crops modeled by the model AquaCrop. This optimization problem is non-trivial due to the non...

  19. Cotton Water Use Efficiency under Two Different Deficit Irrigation Scheduling Methods

    Directory of Open Access Journals (Sweden)

    Jeffrey T. Baker

    2015-08-01

    Full Text Available Declines in Ogallala aquifer levels used for irrigation has prompted research to identify methods for optimizing water use efficiency (WUE of cotton (Gossypium hirsutum L. In this experiment, conducted at Lubbock, TX, USA in 2014, our objective was to test two canopy temperature based stress indices, each at two different irrigation trigger set points: the Stress Time (ST method with irrigation triggers set at 5.5 (ST_5.5 and 8.5 h (ST_8.5 and the Crop Water Stress Index (CWSI method with irrigation triggers set at 0.3 (CWSI_0.3 and 0.6 (CWSI_0.6. When these irrigation triggers were exceeded on a given day, the crop was deficit irrigated with 5 mm of water via subsurface drip tape. Also included in the experimental design were a well-watered (WW control irrigated at 110% of potential evapotranspiration and a dry land (DL treatment that relied on rainfall only. Seasonal crop water use ranged from 353 to 625 mm across these six treatments. As expected, cotton lint yield increased with increasing crop water use but lint yield WUE displayed asignificant (p ≤ 0.05 peak near 3.6 to 3.7 kg ha−1 mm−1 for the ST_5.5 and CWSI_0.3 treatments, respectively. Our results suggest that WUE may be optimized in cotton with less water than that needed for maximum lint yield.

  20. Scheduling irrigation for jujube (Ziziphus jujuba Mill.)

    African Journals Online (AJOL)

    USER

    2010-08-30

    Aug 30, 2010 ... indicators for diagnosing plant water information, but it is troublesome to measure leaf water potential using a pressure chamber (Turner, 1981). It is also difficult to achieve automatic and continuous records with the pressure chamber. Definition of threshold values of soil moisture for irrigation management ...

  1. Factors affecting irrigant extrusion during root canal irrigation: a systematic review

    NARCIS (Netherlands)

    Boutsioukis, C.; Psimma, Z.; van der Sluis, L.W.M.

    2013-01-01

    The aim of the present study was to conduct a systematic review and critical analysis of published data on irrigant extrusion to identify factors causing, affecting or predisposing to irrigant extrusion during root canal irrigation of human mature permanent teeth. An electronic search was conducted

  2. Root Zone Sensors for Irrigation Management in Intensive Agriculture

    Directory of Open Access Journals (Sweden)

    Jochen Hemming

    2009-04-01

    Full Text Available Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method. An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS, such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy.

  3. ARS irrigation research priorities and projects-An update

    Science.gov (United States)

    The USDA Agricultural Research Service focuses on six areas of research that are crucial to safe and effective use of all water resources for agricultural production: 1) Irrigation Scheduling Technologies for Water Productivity; 2) Water Productivity (WP) at Multiple Scales; 3) Irrigation Applicatio...

  4. Soil water sensors for irrigation management-What works, what doesn't, and why

    Science.gov (United States)

    Irrigation scheduling can be greatly improved if accurate soil water content data are available. There are a plethora of available soil water sensing systems, but those that are practical for irrigation scheduling are divided into two major types: the frequency domain (capacitance) sensors and the t...

  5. Using Irrigation Scheduling to Increase Water Productivity of Wheat-Maize Rotation under Climate Change Conditions Calendario de Riego para Aumentar la Productividad del Agua en Rotación Trigo-Maíz en Condiciones de Cambio Climático

    Directory of Open Access Journals (Sweden)

    Gamal El Afandi

    2010-09-01

    Full Text Available Irrigation scheduling was used to increase water productivity of wheat (Triticum aestivum L.-maize (Zea mays L. rotation under two climate change scenarios. Three wheat varieties and two maize hybrids were planted at in a 2-yr field experiment. CropSyst model was calibrated and validated for the collected field data, then was used to assess the impact of two climate change scenarios (A2 and B2 and three adaptation strategies (early sowing changing, irrigation schedule and the interaction between them in the year of 2038s. The results revealed that A2 reduced yield more than B2 scenario for both crops. High yield reduction in wheat-maize rotation could be expected under climate change conditions, where wheat and maize yield will be reduced by an average of 41 and 56%, respectively. The most effective adaptation strategy for wheat was sowing 3 wk earlier and irrigation every 21 d, with irrigation water saving and no yield improvement under A2 scenario in both growing seasons. Whereas under B2 scenario yield improvement by 2% occurred with 3% saving in the applied irrigation water in the 1st growing season and in the 2nd growing season yield could improved by 8% with less than 1% increase in the applied irrigation water and higher water productivity. Changing irrigation schedule was an effective adaptation option for maize, where yield improvement could occur under both climate change scenarios in both growing seasons by up to 9% with less than 3% increase in the applied irrigation water and higher water productivity.

  6. Evapotranspiration-based irrigation scheduling of lettuce and broccoli

    Science.gov (United States)

    Estimation of crop evapotranspiration supports efficient irrigation water management, which in turn supports water conservation, mitigation of groundwater depletion/degradation, energy savings, and crop quality maintenance. Past research in California has revealed strong relationships between fract...

  7. Wireless sensor networks for canopy temperature sensing and irrigation management

    Science.gov (United States)

    For researchers, canopy temperature measurements have proven useful in characterizing crop water stress and developing protocols for irrigation management. Today, there is heightened interest in using remote canopy temperature measurements for real-time irrigation scheduling. However, without the us...

  8. Dimensioning the Irrigation Variables for Table Grape Vineyards in Litho-soils

    Directory of Open Access Journals (Sweden)

    Pasquale Campi

    2010-10-01

    Full Text Available The pedo-climatic and farm characteristics of Bari’s hinterland have allowed for the diffusion of prestigious table viticulture. The typical “tendone” vineyard structure is set up after managing the surface of the soil. The karstic nature of the region and the thermo-rainfall trend during the vegetative season impede the vineyard from producing adequately without irrigation. Given the importance of water contributions to table grapes, it is necessary to correctly measure the water variables for economic and environmental reasons. Farmers often irrigate according to “fixed” turns and volumes, against the rules of “good irrigation practice” which consider monitoring the water status of the soil or plant as a prerequisite of irrigation scheduling. During this experiment, two methods of irrigation management were compared: “fixed-turn” and “on demand”. For “on demand” irrigation, the irrigation volume is calculated on the basis of the soil water status (estimated according to the “water balance” method described in the “Paper n. 56 FAO” and the irrigation is scheduled on the basis of the experimental relationship between “pre-dawn” leaf water potential and the water available in the soil. For this comparison, data from a 2-year “on farm” experimentation, in an area typical of table grape cultivation in Southern Italy, have been used. The results obtained show that, in respect to the “fixed-turn” management, the “on demand” management allows for a 20% reduction in water volumes, without compromising production. The water balance method proved to be a promising criterion for irrigation scheduling in these shallow soils, rich in stones (litho-soils. This only held true when the depth of the soil layer explored by the root system was defined by the “equivalent depth” and not by the actual soil’s depth.

  9. Irrigation Water Management in Latin America

    Directory of Open Access Journals (Sweden)

    Aureo S de Oliveira

    2009-12-01

    Full Text Available Latin American countries show a great potential for expanding their irrigated areas. Irrigation is important for strengthening local and regional economy and for enhancing food security. The present paper aimed at providing a brief review on key aspects of irrigation management in Latin America. Poor irrigation management can have great impact on crop production and on environment while good management reduces the waste of soil and water and help farmers maximizing their profits. It was found that additional research is needed to allow a better understanding of crop water requirements under Latin American conditions as well as to provide farmers with local derived information for irrigation scheduling. The advantages of deficit irrigation practices and the present and future opportunities with the application of remote sensing tools for water management were also considered. It is clear that due to the importance of irrigated agriculture, collaborative work among Latin American researchers and institutions is of paramount importance to face the challenges imposed by a growing population, environment degradation, and competition in the global market.

  10. Wireless sensor network effectively controls center pivot irrigation of sorghum

    Science.gov (United States)

    Robust automatic irrigation scheduling has been demonstrated using wired sensors and sensor network systems with subsurface drip and moving irrigation systems. However, there are limited studies that report on crop yield and water use efficiency resulting from the use of wireless networks to automat...

  11. Tree Canopy Light Interception Estimates in Almond and a Walnut Orchards Using Ground, Low Flying Aircraft, and Satellite Based Methods to Improve Irrigation Scheduling Programs

    Science.gov (United States)

    Rosecrance, Richard C.; Johnson, Lee; Soderstrom, Dominic

    2016-01-01

    Canopy light interception is a main driver of water use and crop yield in almond and walnut production. Fractional green canopy cover (Fc) is a good indicator of light interception and can be estimated remotely from satellite using the normalized difference vegetation index (NDVI) data. Satellite-based Fc estimates could be used to inform crop evapotranspiration models, and hence support improvements in irrigation evaluation and management capabilities. Satellite estimates of Fc in almond and walnut orchards, however, need to be verified before incorporating them into irrigation scheduling or other crop water management programs. In this study, Landsat-based NDVI and Fc from NASA's Satellite Irrigation Management Support (SIMS) were compared with four estimates of canopy cover: 1. light bar measurement, 2. in-situ and image-based dimensional tree-crown analyses, 3. high-resolution NDVI data from low flying aircraft, and 4. orchard photos obtained via Google Earth and processed by an Image J thresholding routine. Correlations between the various estimates are discussed.

  12. Methods to estimate irrigated reference crop evapotranspiration - a review.

    Science.gov (United States)

    Kumar, R; Jat, M K; Shankar, V

    2012-01-01

    Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.

  13. Drip Planner Chart: a simple irrigation scheduling tool for smallholder drip farmers

    NARCIS (Netherlands)

    Boesveld, H.; Zisengwe, L.S.; Yakami, S.

    2012-01-01

    Drip irrigation is widely recognized as potentially one of the most efficient irrigation methods. However, this efficiency is often not achieved because systems are not always well designed or maintained and many farmers lack the tools to assess the crop water requirements and to monitor the soil

  14. Agronomic and physiological impacts of irrigation frequency on green basil (Ocimum basilicum L.)

    OpenAIRE

    Gao, Peng; Dodd, Ian

    2015-01-01

    Water scarcity is a major factor restricting agricultural production and irrigation globally, with sustainable agricultural development calling for less irrigation water use and more production per unit of water applied. Improved understanding of plant physiological responses to water stress, and the effect of irrigation frequency on plant biomass production and quality, may help to optimize irrigation scheduling. Glasshouse-grown basil (Ocimum basilicum L.) received three different irrigatio...

  15. Performance of a wireless sensor network for crop monitoring and irrigation control

    Science.gov (United States)

    Robust automatic irrigation scheduling has been demonstrated using wired sensors and sensor network systems with subsurface drip and moving irrigation systems. However, there are limited studies that report on crop yield and water use efficiency resulting from the use of wireless networks to automat...

  16. EQUITY EVALUATION OF PADDY IRRIGATION WATER DISTRIBUTION BY SOCIETY-JUSTICE-WATER DISTRIBUTION RULE HYPOTHESIS

    Science.gov (United States)

    Tanji, Hajime; Kiri, Hirohide; Kobayashi, Shintaro

    When total supply is smaller than total demand, it is difficult to apply the paddy irrigation water distribution rule. The gap must be narrowed by decreasing demand. Historically, the upstream served rule, rotation schedule, or central schedule weight to irrigated area was adopted. This paper proposes the hypothesis that these rules are dependent on social justice, a hypothesis called the "Society-Justice-Water Distribution Rule Hypothesis". Justice, which means a balance of efficiency and equity of distribution, is discussed under the political philosophy of utilitarianism, liberalism (Rawls), libertarianism, and communitarianism. The upstream served rule can be derived from libertarianism. The rotation schedule and central schedule can be derived from communitarianism. Liberalism can provide arranged schedule to adjust supply and demand based on "the Difference Principle". The authors conclude that to achieve efficiency and equity, liberalism may provide the best solution after modernization.

  17. Integration of wireless sensor networks into automatic irrigation scheduling of a center pivot

    Science.gov (United States)

    A six-span center pivot system was used as a platform for testing two wireless sensor networks (WSN) of infrared thermometers. The cropped field was a semi-circle, divided into six pie shaped sections of which three were irrigated manually and three were irrigated automatically based on the time tem...

  18. Farm-based measures for reducing microbiological health risks for consumers from informal wastewater-irrigated agriculture

    DEFF Research Database (Denmark)

    Keraita, Bernard; Konradsen, Flemming; Drechsel, Pay

    2010-01-01

    in developing countries as part of a multiple-barrier approach for health-risk reduction along the farm to fork pathway. Measures discussed include treatment of irrigation water using ponds, filters and wetland systems; water application techniques; irrigation scheduling; and crop selection. In addition...

  19. Soil water sensors:Problems, advances and potential for irrigation scheduling

    Science.gov (United States)

    Irrigation water management has to do with the appropriate application of water to soils, in terms of amounts, rates, and timing to satisfy crop water demands, while protecting the soil and water resources from degradation. In this regard, sensors can be used to monitor the soil water status; and so...

  20. Impacts of irrigation regimes with saline water on carrot productivity and soil salinity

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-01-01

    salts from the root zone. Highest carrot yields for the three years were obtained with SWB scheduling technique FI-100, (29.5, 28.7 and 26.8 t/ha although we didn’t find significant differences with the regulated deficit irrigation regime (FI-DI60. Compared to FI-100, significant reductions in carrot yields were observed under DI-80 and DI-60 deficit irrigation treatments resulting from a reduction in roots number/m2 and average root weight. The farmer’s method not only caused significant reductions in yield but also resulted in using 43–57% more water and increased soil salinity. For all irrigation treatments, carrot yields were higher in the first year compared to the two following years. Water productivity (WP values reflected this difference and varied between 3.2 and 9.7 kg/m3. The lowest WP values were observed for the farmer’s method, while the highest values were obtained under DI-60 deficit irrigation treatment. The scheduling technique using SWB with variable doses is more efficient than the traditional technique used by farmers in carrot production. The FI-100 irrigation scheduling seems to optimize the use of saline water in carrot production and to control soil salinity. Under situations of water shortage, adopting deficit irrigation strategies (FI-DI60 and DI-80 could be an alternative for irrigation scheduling of carrot crop under the conditions of Mediterranean arid in southern Tunisia.

  1. Comparative evaluation of accuracy of two electronic apex locators in the presence of various irrigants: An in vitro study

    Directory of Open Access Journals (Sweden)

    Saru Jain

    2012-01-01

    Full Text Available Context: The establishment of appropriate working length is one of the most critical steps in endodontic therapy. Electronic apex locators have been introduced to determine the working length. The development of electronic apex locators has helped make the assessment of the working length more accurate and predictable, along with reduction in treatment time and radiation dose. Objectives: The aim of this study was to compare the efficacy of electronic apex locators after cleansing and shaping of the root canals and whether there was any alteration in accuracy when used in the presence of irrigants. Materials and Methods: Seventy extracted human permanent molars with mature apices were selected. Equal number of maxillary and mandibular permanent molars (35 each were sectioned at the cemento-enamel junction. Access opening was done and only the mesiobuccal root canal was studied for the purpose of standardization. Electronic working length measurements were taken before and after preparation of the mesiobuccal canal with Root ZX and ProPex II using various irrigants. Statistical Analysis Used: The data were statistically analyzed using a paired t-test at 0.05 level of significance. Results: P-values for actual and final canal lengths for Root ZX employing NaoCl(0.001, CHX(0.006, LA(0.020 and for ProPex II was (0.001 respectively. When the data were compared, results were statistically significant (P < 0.05. Conclusion: Within the limitations of this study Root ZX can be considered to be an accurate electronic apex locator and CHX as irrigant matched more precisely with the actual canal length measurements.

  2. Water-Yield Relations of Drip Irrigated Watermelon in Temperate Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2016-08-01

    Full Text Available The objective of the study, conducted in Vojvodina a northern part of the Serbia Republic, was to analyse the effect of drip irrigation on yield, evapotranspiration and water productivity of watermelon (Cirullus lanatus Thunb. grown with plasticulture. Irrigation was scheduled on the basis of water balance method. Daily evapotranspiration was computed using the reference evapotranspiration and crop coefficient. The yield of watermelon in irrigation conditions (37,28 t/ha was significantly higher compared to non irrigated (9,98 t/ha. Water used on evapotranspiration in irrigation conditions was 398 mm and 117 mm on non irrigated variant. The crop yield response factor of 1,04 for the whole growing season reveals that relative yield decrease was nearly equal to the rate of evapotranspiration deficit. The values of irrigation water use efficiency and evapotranspiration water use efficiency were 9,93 kg/m3 and 10,29 kg/m3 respectively. The determined results could be used as a good platform for watermelon growers in the region, in terms of improvement of the optimum utilization of irrigation water.

  3. Tomato yield, biomass accumulation, root distribution and irrigation water use efficiency on a sandy soil, as affected by nitrogen rate and irrigation scheduling

    NARCIS (Netherlands)

    Zotarelli, L.; Scholberg, J.M.S.; Dukes, M.D.; Munoz-Carpena, R.; Icerman, J.

    2009-01-01

    Florida is the largest producer of fresh-market tomatoes in the United States. Production areas are typically intensively managed with high inputs of fertilizer and irrigation. The objectives of this 3-year field study were to evaluate the interaction between N-fertilizer rates and irrigation

  4. Coordinated research project of the use of nuclear and related techniques in assessment of irrigation schedules of field crops to increase effective use of water in irrigation projects

    International Nuclear Information System (INIS)

    Anac, M.S.; Tuzel, I.H.; Anac, D.

    1995-01-01

    The study aimed at determining the followings; water consumptions. irrigation water requirements of new cotton variety N 84; specific growth stages of cotton which are less sensitive to stress so that the irrigation could be avoided without significant yield decrease; and interactions between deficit irrigation and nitrogen fertilizer use. The experiment was set up with 6 irrigation and three nitrogen fertilizer (0.60 , 120 kg.ha sup -1 ) treatments. The irrigation treatments employed single stress at vegetative, flowering and boll formation stages, in addition to full irrigation, continuous stress and the traditional practice. In stress conditions available soil water depleted to 75 - 80 %, whereas in normal irrigation the depletion was 40 % in 0.90 m. of root zone. In full irrigation treatment 8 irrigations were applied, whereas 3 or 4 irrigations were needed in continuous stress conditions. The number of irrigations were 6 or 7 for other stress treatments. Irrigation water applications varied form 424 to 751 mm. Seasonal ET were ranged between 659 and 899 mm. The highest monthly ET in august for all of the treatments. Daily ET were found to vary from 2.2 to 12.1 mm/day. The seed cotton yields, ky values and yield - N indices have indicated that the vegetative state was more sensitive to water stress. The stress at boll formation stage had slight effects on these parameters. Under limited water resource conditions, vegetative growth period of cotton should be given preference for irrigation, followed by flowering period. Omitting irrigation in boll formation period would result in 4.3 to 9.1 % water savings. Yield changes with respect to N rates showed that high N doses are accompanied by high yields. Nitrogen recoveries either from fertilizers or soil revealed high uptakes in full irrigation conditions. Nitrogen use efficiencies were also high in these conditions. Average of three years put forth that 19% of N in stress conditions and 29% in full irrigation were

  5. Streamflow Prediction in Ungauged, Irrigated Basins

    Science.gov (United States)

    Zhang, M.; Thompson, S. E.

    2016-12-01

    The international "predictions in ungauged basins" or "PUB" effort has broadened and improved the tools available to support water resources management in sparsely observed regions. These tools have, however, been primarily focused on regions with limited diversion of surface or shallow groundwater resources. Incorporating anthropogenic activity into PUB methods is essential given the high level of development of many basins. We extended an existing stochastic framework used to predict the flow duration curve to explore the effects of irrigation on streamflow dynamics. Four canonical scenarios were considered in which irrigation water was (i) primarily sourced from water imports, (ii) primarily sourced from direct in-channel diversions, (iii) sourced from shallow groundwater with direct connectivity to stream channels, or (iv) sourced from deep groundwater that is indirectly connected to surface flow via a shallow aquifer. By comparing the predicted flow duration curves to those predicted by accounting for climate and geomorphic factors in isolation, specific "fingerprints" of human water withdrawals could be identified for the different irrigation scenarios, and shown to be sensitive to irrigation volumes and scheduling. The results provide a first insight into PUB methodologies that could be employed in heavily managed basins.

  6. Irrigation scheduling research: South African experiences and future ...

    African Journals Online (AJOL)

    This paper was originally presented at the Water Research. Commission 40-Year .... direct link with dry matter production (Tanner and Sinclair,. 1983). Scheduling ..... type infrared thermometer for measuring canopy temperature received much ..... subscribers and advice was made available through web down- loads for ...

  7. Adaptive management of irrigation and crops' biodiversity: a case study on tomato

    Science.gov (United States)

    De Lorenzi, Francesca; Alfieri, Silvia Maria; Basile, Angelo; Bonfante, Antonello; Monaco, Eugenia; Riccardi, Maria; Menenti, Massimo

    2013-04-01

    We have assessed the impacts of climate change and evaluated options to adapt irrigation management in the face of predicted changes of agricultural water demand. We have evaluated irrigation scheduling and its effectiveness (versus crop transpiration), and cultivars' adaptability. The spatial and temporal variations of effectiveness and adaptability were studied in an irrigated district of Southern Italy. Two climate scenarios were considered: reference (1961-90) and future (2021-2050) climate, the former from climatic statistics, and the latter from statistical downscaling of general circulation models (AOGCM). Climatic data consist of daily time series of maximum and minimum temperature, and daily rainfall on a grid with a spatial resolution of 35 km. The work was carried out in the Destra Sele irrigation scheme (18.000 ha. Twenty-five soil units were identified and their hydrological properties were determined (measured or estimated from texture through pedo-transfer functions). A tomato crop, in a rotation typical of the area, was considered. A mechanistic model of water flow in the soil-plant-atmosphere system (SWAP) was used to study crop water requirements and water consumption. The model was calibrated and validated in the same area for many different crops. Tomato crop input data and model parameters were estimated on the basis of scientific literature and assumed to be generically representative of the species. Simulations were performed for reference and future climate, and for different irrigation scheduling options. In all soil units, six levels of irrigation volumes were applied: full irrigation (100%), deficit irrigation (80%, 60%, 40%, 20%), no irrigation. From simulation runs, indicators of soil water availability were calculated, moreover the marginal increases of transpiration per unit of irrigation volume, i.e. the effectiveness of irrigation (ΔT/I), were computed, in both climate scenarios. Indicators and marginal increases were used to

  8. Predicting deep percolation with eddy covariance under mulch drip irrigation

    Science.gov (United States)

    Ming, Guanghui; Tian, Fuqiang; Hu, Hongchang

    2016-04-01

    Water is essential for the agricultural development and ecological sustainability of the arid and semi-arid oasis with rare precipitation input and high evaporation demand. Deep percolation (DP) defined as excess irrigation water percolating below the plant root zone will reduce irrigation water use efficiency (WUE). But the DP was often ignored in mulch drip irrigation (MDI) which has reached the area of 1.6 million hectares in Xinjiang, the northwest of China. In this study DP experiments were conducted at an agricultural experiment station located within an irrigation district in the Tarim River Basin for four cotton growing periods. First it was detected the irrigation water infiltrated into the soil layers below 100cm and the groundwater level responded to the irrigation events well. Then DP below 100cm soil layers was calculated using the soil water balance method with the aid of eddy covariance (with the energy balance closure of 0.72). The negative DP (groundwater contribution to the crop-water use through capillary rising) at the seedling and harvesting stages can reach 77mm and has a good negative correlation with the groundwater level and positive correlation with potential evaporation. During the drip irrigation stage approximately 45% of the irrigation became DP and resulted in the low irrigation WUE of 0.6. The DP can be 164mm to 270mm per year which was positive linearly correlated to irrigation depth and negative linear correlated to irrigation interval. It is better to establish the irrigation schedule with small irrigation depth and given frequently to reduce deep percolation and meet crop needs.

  9. Ancestral irrigation method by kanis in Bolivia

    Science.gov (United States)

    Roldán-Cañas, José; Chipana, René; Fátima Moreno-Pérez, María

    2015-04-01

    Irrigation in the Andean region is an ancient practice. For centuries, farmers were able to use the waters of rivers, lakes and springs to complement or supplement the scarce rainfall regime. The inter-Andean valleys of the Department of La Paz are the best areas for the study of traditional irrigation systems. This work has been carried out in the community of Jatichulaya located in te town of Charazani, 300 km from the city of La Paz, which lies 3250 meters above sea level. The annual rainfall ranges around 450 mm distributed mainly between the months of December to March. Therefore, water is needed to achieve adequate crop yields. The traditional irrigation system is done by the method of Kanis, consisting of a surface irrigation already developed by traditional Andean cultures of the country, in harmony with the ecological and productive characteristics of the area. Water enters the irrigation plot through a main channel (mama kani) from which the secondary channels (juchuy kanis) are derived. The fundamental characteristic of this irrigation is that these channels are open at the same time the water enters into the plot. The system works properly, adapting to the topography of the area. The irrigation method practiced in this community does not cause water erosion of soils because water management within the plot is based on the ancient knowledge of farmers following the contour lines. This practice allows good irrigation development and soil protection without causing any problems. However, it was evident a high use of labor in irrigation practice. Irrigation scheduling is done according to requests made by the irrigators in a given period. Delivering of water to the farmers is made by the so-called Water Agent (Agente de Aguas) or person in charge of the distribution of water. The Water Agent is elected annually and its functions include the maintenance and care of all system waterworks. The period between August and January is the highest water demand and

  10. Untangling the effects of shallow groundwater and deficit irrigation on irrigation water productivity in arid region: New conceptual model.

    Science.gov (United States)

    Xue, Jingyuan; Huo, Zailin; Wang, Fengxin; Kang, Shaozhong; Huang, Guanhua

    2018-04-01

    Water scarcity and salt stress are two main limitations for agricultural production. Groundwater evapotranspiration (ET g ) with upward salt movement plays an important role in crop water use and water productivity in arid regions, and it can compensate the impact of deficit irrigation on crop production. Thus, comprehensive impacts of shallow groundwater and deficit irrigation on crop water use results in an improvement of irrigation water productivity (IWP). However, it is difficult to quantify the effects of groundwater and deficit irrigation on IWP. In this study, we built an IWP evaluation model coupled with a water and salt balance model and a crop yield estimation model. As a valuable tool of IWP simulation, the calibrated model was used to investigate the coupling response of sunflower IWP to irrigation water depths (IWDs), groundwater table depth (GTDs) and groundwater salinities (GSs). A total of 210 scenarios were run in which five irrigation water depths (IWDs) and seven groundwater table depths (GTDs) and six groundwater salinities (GSs) were used. Results indicate that increasing GS clearly increases the negative effect on a crop's actual evapotranspiration (ET a ) as salt accumulation in root zone. When GS is low (0.5-1g/L), increasing GTD produces more positive effect than negative effect. In regard to relatively high GS (2-5g/L), the negative effect of shallow-saline groundwater reaches a maximum at 2m GTD. Additionally, the salt concentration in the root zone maximizes its value at 2.0m GTD. In most cases, increasing GTD and GS reduces the benefits of irrigation water and IWP. The IWP increases with decreasing irrigation water. Overall, in arid regions, capillary rise of shallow groundwater can compensate for the lack of irrigation water and improve IWP. By improving irrigation schedules and taking advantages of shallow saline groundwater, we can obtain higher IWP. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Water saving at the field scale with Irrig-OH, an open-hardware environment device for soil water potential monitoring and irrigation management

    Science.gov (United States)

    Masseroni, Daniele; Facchi, Arianna; Gandolfi, Claudio

    2015-04-01

    Sustainability of irrigation practices is an important objective which should be pursued in many countries, especially in areas where water scarcity causes strong conflicts among the different water uses. The efficient use of water is a key factor in coping with the food demand of an increasing world population and with the negative effects of the climate change on water resources availability in many areas. In this complex context, it is important that farmers adopt instruments and practices that enable a better management of water at the field scale, whatever the irrigation method they adopt. This work presents the hardware structure and the functioning of an open-hardware microstation based on the Arduino technology, called Irrig-OH, which allows the continuous and low-cost monitoring of the soil water potential (SWP) in the root zone for supporting the irrigation scheduling at the field scale. In order to test the microstation, an experiment was carried out during the agricultural season 2014 at Lodi (Italy), with the purpose of comparing the farmers' traditional management of irrigation of a peach variety and the scheduling based on the SWP measurements provided by the microstation. Additional measurements of leaf water potential (LWP), stomatal resistance, transpiration (T), crop water stress index (CWSI) and fruit size evolution were performed respectively on leafs and fruits for verifying the plant physiological responses on different SWP levels in soil. At the harvesting time, the peach production in term of quantity and quality (sucrose content was measured by a rifractometer over a sample of one hundred fruits) of the two rows were compared. Irrigation criteria was changed with respect to three macro-periods: up to the endocarp hardening phase (begin of May) soil was kept well watered fixing the SWP threshold in the first 35 cm of the soil profile at -20 kPa, during the pit hardening period (about the entire month of May) the allowed SWP threshold was

  12. A review of mechanical move sprinkler irrigation control and automation technologies

    Science.gov (United States)

    Electronic sensors, equipment controls, and communication protocols have been developed to meet the growing interest in site-specific irrigation using center pivot and lateral move irrigation systems. Onboard and field-distributed sensors can collect data necessary for real-time irrigation manageme...

  13. Soil nitrate testing supports nitrogen management in irrigated annual crops

    Directory of Open Access Journals (Sweden)

    Patricia A. Lazicki

    2016-12-01

    Full Text Available Soil nitrate (NO3− tests are an integral part of nutrient management in annual crops. They help growers make field-specific nitrogen (N fertilization decisions, use N more efficiently and, if necessary, comply with California's Irrigated Lands Regulatory Program, which requires an N management plan and an estimate of soil NO3− from most growers. As NO3− is easily leached into deeper soil layers and groundwater by rain and excess irrigation water, precipitation and irrigation schedules need to be taken into account when sampling soil and interpreting test results. We reviewed current knowledge on best practices for taking and using soil NO3− tests in California irrigated annual crops, including how sampling for soil NO3− differs from sampling for other nutrients, how tests performed at different times of the year are interpreted and some of the special challenges associated with NO3− testing in organic systems.

  14. Proposed Fuzzy-NN Algorithm with LoRaCommunication Protocol for Clustered Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Sotirios Kontogiannis

    2017-11-01

    Full Text Available Modern irrigation systems utilize sensors and actuators, interconnected together as a single entity. In such entities, A.I. algorithms are implemented, which are responsible for the irrigation process. In this paper, the authors present an irrigation Open Watering System (OWS architecture that spatially clusters the irrigation process into autonomous irrigation sections. Authors’ OWS implementation includes a Neuro-Fuzzy decision algorithm called FITRA, which originates from the Greek word for seed. In this paper, the FITRA algorithm is described in detail, as are experimentation results that indicate significant water conservations from the use of the FITRA algorithm. Furthermore, the authors propose a new communication protocol over LoRa radio as an alternative low-energy and long-range OWS clusters communication mechanism. The experimental scenarios confirm that the FITRA algorithm provides more efficient irrigation on clustered areas than existing non-clustered, time scheduled or threshold adaptive algorithms. This is due to the FITRA algorithm’s frequent monitoring of environmental conditions, fuzzy and neural network adaptation as well as adherence to past irrigation preferences.

  15. Evaluation of different methods of measuring evapotranspiration as a scheduling guide for drip-irrigated cotton

    International Nuclear Information System (INIS)

    Rawitz, E.; Marani, A.; Mahrer, Y.; Berkovich, D.

    1983-01-01

    Evapotranspiration in a drip-irrigated cotton field was estimated by the energy balance method, net radiation, standard evaporation pan, evaporation pan in the field at canopy height, and by the Penman equation, and the results were compared with the soil-water balance based on neutron meter and tensiometer data from seven observation sites. Evapotranspiration according to the soil-water balance was only about 85% of that determined by the energy balance method, and this is attributed to the fact that irrigation laterals were placed every second row, and the soil-water balance was determined in the irrigated rows. The crop also utilized moisture stored from winter rains in the unirrigated inter-row spaces, which was detected by the energy balance method. Actual evapotranspiration (ET) was 96% of potential ET (Penman), and the latter equalled 98% of net radiation energy. The actual ET equalled 90% of free water evaporation from the pan in the field at canopy height, and 88% of net radiation. The high-frequency drip regime maintained ET very close to potential ET, and under these conditions the field-installed evaporation pan, or the net radiometer, are good indicators of crop water use, with the latter being adaptable to computer-controlled irrigation. (author)

  16. Effectiveness of four different final irrigation activation techniques on smear layer removal in curved root canals : a scanning electron microscopy study.

    Directory of Open Access Journals (Sweden)

    Puneet Ahuja

    2014-02-01

    Full Text Available The aim of this study was to assess the efficacy of apical negative pressure (ANP, manual dynamic agitation (MDA, passive ultrasonic irrigation (PUI and needle irrigation (NI as final irrigation activation techniques for smear layer removal in curved root canals.Mesiobuccal root canals of 80 freshly extracted maxillary first molars with curvatures ranging between 25° and 35° were used. A glide path with #08-15 K files was established before cleaning and shaping with Mtwo rotary instruments (VDW, Munich, Germany up to size 35/0.04 taper. During instrumentation, 1 ml of 2.5% NaOCl was used at each change of file. Samples were divided into 4 equal groups (n=20 according to the final irrigation activation technique: group 1, apical negative pressure (ANP (EndoVac; group 2, manual dynamic agitation (MDA; group 3, passive ultrasonic irrigation (PUI; and group 4, needle irrigation (NI. Root canals were split longitudinally and subjected to scanning electron microscopy. The presence of smear layer at coronal, middle and apical levels was evaluated by superimposing 300-μm square grid over the obtained photomicrographs using a four-score scale with X1,000 magnification.Amongst all the groups tested, ANP showed the overall best smear layer removal efficacy (p < 0.05. Removal of smear layer was least effective with the NI technique.ANP (EndoVac system can be used as the final irrigation activation technique for effective smear layer removal in curved root canals.

  17. Real-Time Robust Adaptive Modeling and Scheduling for an Electronic Commerce Server

    Science.gov (United States)

    Du, Bing; Ruan, Chun

    With the increasing importance and pervasiveness of Internet services, it is becoming a challenge for the proliferation of electronic commerce services to provide performance guarantees under extreme overload. This paper describes a real-time optimization modeling and scheduling approach for performance guarantee of electronic commerce servers. We show that an electronic commerce server may be simulated as a multi-tank system. A robust adaptive server model is subject to unknown additive load disturbances and uncertain model matching. Overload control techniques are based on adaptive admission control to achieve timing guarantees. We evaluate the performance of the model using a complex simulation that is subjected to varying model parameters and massive overload.

  18. Basin Irrigation Design with Multi-Criteria Analysis Focusing on Water Saving and Economic Returns: Application to Wheat in Hetao, Yellow River Basin

    Directory of Open Access Journals (Sweden)

    Qingfeng Miao

    2018-01-01

    Full Text Available The sustainability of the Hetao Irrigation System, located in the water scarce upper Yellow River basin, is a priority considering the need for water saving, increased water productivity, and higher farmers’ incomes. The upgrading of basin irrigation, the main irrigation method, is essential and includes the adoption of precise land levelling, cut-off management, improved water distribution uniformity, and adequate irrigation scheduling. With this objective, the current study focuses on upgrading wheat basin irrigation through improved design using a decision support system (DSS model, which considers land parcels characteristics, crop irrigation scheduling, soil infiltration, hydraulic simulation, and environmental and economic impacts. Its use includes outlining water saving scenarios and ranking alternative designs through multi-criteria analysis considering the priorities of stakeholders. The best alternatives concern flat level basins with a 100 and 200 m length and inflow rates between 2 and 4 L s−1 m−1. The total irrigation cost of designed projects, including the cost of the autumn irrigation, varies between 2400 and 3300 Yuan ha−1; the major cost component is land levelling, corresponding to 33–46% of total irrigation costs. The economic land productivity is about 18,000 Yuan ha−1. The DSS modelling defined guidelines to be applied by an extension service aimed at implementing better performing irrigation practices, and encouraged a good interaction between farmers and the Water Users Association, thus making easier the implementation of appropriate irrigation management programs.

  19. A Smart Irrigation Approach Aided by Monitoring Surface Soil Moisture using Unmanned Aerial Vehicles

    Science.gov (United States)

    Wienhold, K. J.; Li, D.; Fang, N. Z.

    2017-12-01

    Soil moisture is a critical component in the optimization of irrigation scheduling in water resources management. Unmanned Aerial Vehicles (UAV) equipped with multispectral sensors represent an emerging technology capable of detecting and estimating soil moisture for irrigation and crop management. This study demonstrates a method of using a UAV as an optical and thermal remote sensing platform combined with genetic programming to derive high-resolution, surface soil moisture (SSM) estimates. The objective is to evaluate the feasibility of spatially-variable irrigation management for a golf course (about 50 acres) in North Central Texas. Multispectral data is collected over the course of one month in the visible, near infrared and longwave infrared spectrums using a UAV capable of rapid and safe deployment for daily estimates. The accuracy of the model predictions is quantified using a time domain reflectometry (TDR) soil moisture sensor and a holdout validation test set. The model produces reasonable estimates for SSM with an average coefficient of correlation (r) = 0.87 and coefficient of determination of (R2) = 0.76. The study suggests that the derived SSM estimates be used to better inform irrigation scheduling decisions for lightly vegetated areas such as the turf or native roughs found on golf courses.

  20. Yield and water use efficiency of irrigated soybean in Vojvodina, Serbia

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2012-01-01

    Full Text Available Research was carried out at Rimski Šančevi experiment field of Institute of Field and Vegetable Crops in Novi Sad in the period 1993-2004. The experiment included an irrigated and non-irrigated control treatment. Irrigation water use efficiency (Iwue and evapotranspiration water use efficiency (ETwue were determined in order to assess the effectiveness of irrigation on soybean yield. The average yield increases of soybean due to irrigation practice was 0.82 t ha-1, ranging from 2.465 t ha-1 in years with limited precipitation and higher than average seasonal temperatures (2000 to 0 t ha-1 in rainy years (1996, 1997, 1999. Evapotranspiration water use efficiency (ETwue of soybean ranged from 0.11 kg m-3 to 1.36 kg m-3 with an average value of 0.66 kg m-3, while irrigation water use efficiency (Iwue varied from 0.11 kg m-3 to 1.04 kg m-3 with an average value of 0.56 kg m-3. Effect of irrigation on yield of soybean and results of both ETwue and Iwue which were similar to those obtained from the literature indicate that irrigation schedule of soybean in the study period was properly adapted to plant water requirements and water-physical soil properties. Determined values of ETwue and Iwue could be used for the planning, design and operation of irrigation systems, as well as for improving the production technology of soybean in the region.

  1. Water relations and photosynthesis as criteria for adequate irrigation management in 'Tahiti' lime trees

    Directory of Open Access Journals (Sweden)

    Silva Cláudio Ricardo da

    2005-01-01

    Full Text Available Irrigation scheduling based on soil moisture status is one of the most useful methods because of its practicality and low cost. The effects of available soil water depletion on evapotranspiration (ETc, transpiration (E, leaf water potential at predawn (psiP and midday (psiM, stomatal conductance (gs and net CO2 assimilation (A in lime 'Tahiti' trees (Citrus latifolia were evaluated to improve irrigation schedule and minimize water use without causing water stress. The trees were spaced 7 4 m and drip-irrigated by four drippers with the available soil water content (AWC depleted by suspension of irrigation (40 days. Leaf water potential was measured on a pressure chamber (psiP and psiM and leaf gas exchange was measured by infrared gas analyzer (E, gs and A. Evapotranspiration was determined with the aid of weighing lysimeter. Water soil content and potential (psiS were monitored with TDR probes and tensiometers, respectively, installed at 0.3, 0.6 and 0.9 m depths. Meteorological variables were monitored with an automatic weather station in the experimental area. The threshold AWC level for the onset of ETc decline was 43%, and 60% for gs, A, E and Y P. Also, psiP was more sensitive to AWC than psiM, and is therefore a better tool for irrigation. When AWC was around 60%, values of psiP and psis were -0.62 MPa and -48.8 kPa, respectively.

  2. Management Strategies to Sustain Irrigated Agriculture with Combination of Remote Sensing, Weather Monitoring & Forecasting and SWAP Modeling

    Science.gov (United States)

    Ermolaeva, Olga; Zeyliger, Anatoly

    2017-04-01

    Today world's water systems face formidable threats due to climate change and increasing water withdraw for agriculture, industry and domestic use. Projected in many parts of the earth increases in temperature, evaporation, and drought frequency shrunk water availability and magnify water scarcity. Declining irrigation water supplies threaten the sustainability of irrigated agricultural production which plays a critical role in meeting global food needs. In irrigated agriculture there is a strong call for deep efforts in order on the one hand to improve water efficiency use and on the other to maximize yields. The aim of this research is to provide tool to optimize water application with crop irrigation by sprinkling in order to sustain irrigated agriculture under limited water supply by increasing net returns per unit of water. For this aim some field experimental results of 2012 year growing season of alfalfa, corn and soya irrigated by sprinkling machines crops at left bank of Volga River at Saratov Region of Russia. Additionally a combination of data sets was used which includes MODIS images, local meteorological station and results of SWAP (Soil-Water-Atmosphere-Plant) modeling. This combination was used to estimate crop water stress defined as ratio between actual (ETa) and potential (ETc) evapotranspiration. By this way it was determined the effect of applied irrigation scheduling and water application depths on evapotranspiration, crop productivity and water stress coefficient. Aggregation of actual values of crop water stress and biomass data predicted by SWAP agrohydrological model with weather forecasting and irrigation scheduling was used to indicate of both rational timing and amount of irrigation water allocation. This type of analysis facilitating an efficient water management can be extended to irrigated areas by developing maps of water efficiency application serving as an irrigation advice system for farmers at his fields and as a decision support

  3. Digging, Damming or Diverting? Small-Scale Irrigation in the Blue Nile Basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    Irit Eguavoen

    2012-10-01

    Full Text Available The diversity of small-scale irrigation in the Ethiopian Blue Nile basin comprises small dams, wells, ponds and river diversion. The diversity of irrigation infrastructure is partly a consequence of the topographic heterogeneity of the Fogera plains. Despite similar social-political conditions and the same administrative framework, irrigation facilities are established, used and managed differently, ranging from informal arrangements of households and 'water fathers' to water user associations, as well as from open access to irrigation schedules. Fogera belongs to Ethiopian landscapes that will soon transform as a consequence of large dams and huge irrigation schemes. Property rights to land and water are negotiated among a variety of old and new actors. This study, based on ethnographic, hydrological and survey data, synthesises four case studies to analyse the current state of small-scale irrigation. It argues that all water storage options have not only certain comparative advantages but also social constraints, and supports a policy of extending water storage 'systems' that combine and build on complementarities of different storage types instead of fully replacing diversity by large dams.

  4. Irrigation management strategies to improve Water Use Efficiency of potatoes crop in Central Tunisia

    Science.gov (United States)

    Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid

    2015-04-01

    In Tunisia, the expansion of irrigated area and the semiarid climate make it compulsory to adopt strategies of water management to increase water use efficiency. Subsurface drip irrigation (SDI), providing the application of high frequency small irrigation volumes below the soil surface have been increasingly used to enhance irrigation efficiency. At the same time, deficit irrigation (DI) has shown successful results with a large number of crop in various countries. However, for some crops like potatoes, DI is difficult to manage due to the rapid effect of water stress on tuber yield. Irrigation frequency is a key factor to schedule subsurface drip irrigation because, even maintaining the total seasonal volume, soil wetting patterns can result different during the growth period, with consequence on crop yield. Despite the need to enhance water use efficiency, only a few studies related to deficit irrigation of horticultural crops have been made in Tunisia. Objective of the paper was to assess the effects of different on-farm irrigation strategies on water use efficiency of potatoes crop irrigated with subsurface drip irrigation in a semiarid area of central Tunisia. After validation, Hydrus-2D model was used to simulate soil water status in the root zone, to evaluate actual crop evapotranspiration and then to estimate indirectly water use efficiency (IWUE), defined as the ratio between crop yield and total amount of water supplied with irrigation. Field experiments, were carried out in Central Tunisia (10° 33' 47.0" E, 35° 58' 8.1° N, 19 m a.s.l) on a potatoes crop planted in a sandy loam soil, during the growing season 2014, from January 15 (plantation of tubers) to May 6 (harvesting). Soil water status was monitored in two plots (T1 and T2) maintained under the same management, but different irrigation volumes, provided by a SDI system. In particular, irrigation was scheduled according to the average water content measured in the root zone, with a total of 8

  5. A comparative evaluation of working length with digital radiography and third generation apex locator (ProPex in the presence of various intracanal irrigants: An in vivo/ex vivo study

    Directory of Open Access Journals (Sweden)

    Irfana Khursheed

    2014-01-01

    Full Text Available Background: Accurate working length determination is a pre-requisite for a successful endodontic treatment. Even with improved systems of working length measurement, different readings may be recorded in different electrolytes present in the canal. The purpose of this in vivo/ex vivo comparative study was to determine the accuracy in measuring the working length of root canal using Direct Digital Radiographic Method (Radiovisiography or RVG and ProPex electronic apex locator in the presence of three different irrigating solutions: 0.9% normal saline, 2% chlorhexidine, 3% NaOCl solutions. Materials and Methods: Forty single-rooted human teeth scheduled for extraction with mature apices were selected for this study. Measurements were performed by using RVG and ProPex in the presence of irrigating solutions. After extraction of the teeth, light microscope was used to confirm visually the relationship of the tip of the endodontic file to the apical foramen, and actual lengths were determined by reducing 0.5 mm from this length. The statistical analysis was performed by one-way ANOVA test and Tukey-HSD post hoc procedure. P < 0.05 was considered as significant. Results: No significant difference was found between overall mean electronic working length and digital radiographic length; however, prediction error (P < 0.05 was significant with respect to different irrigants. Among the irrigating solutions, chlorhexidine gluconate had the smallest distance to the actual lengths, whereas NaOCl had the greatest. Conclusion: Electronic apex locator ProPex yielded best result in the presence of chlorhexidine, whereas the largest error was demonstrated with NaOCl indicating that higher electroconductive irrigating solutions affect the precision of multi-frequency apex locators.

  6. Opportunities for woody crop production using treated wastewater in Egypt. II. Irrigation strategies.

    Science.gov (United States)

    Evett, Steven R; Zalesny, Ronald S; Kandil, Nabil F; Stanturf, John A; Soriano, Chris

    2011-01-01

    An Egyptian national program targets annual reuse of 2.4 billion m3 of treated wastewater (TWW) to irrigate 84,000 ha of manmade forests in areas close to treatment plants and in the desert. To evaluate the feasibility of such afforestation efforts, we describe information about TWW irrigation strategies based on (1) water use of different tree species, (2) weather conditions in different climate zones of Egypt, (3) soil types and available irrigation systems, and (4) the requirement to avoid deep percolation losses that could lead to groundwater contamination. We conclude that drip irrigation systems are preferred, that they should in most cases use multiple emitters per tree in order to increase wetted area and decrease depth of water penetration, that deep rooting should be encouraged, and that in most situations irrigation system automation is desirable to achieve several small irrigations per day in order to avoid deep percolation losses. We describe directed research necessary to fill knowledge gaps about depth of rooting of different species in sandy Egyptian soils and environments, tree crop coefficients needed for rational irrigation scheduling, and depth of water penetration under different irrigation system designs. A companion paper addresses recommendations for afforestation strategies (see Zalesny et al. 2011, this issue).

  7. A short overview of measures for securing water resources for irrigated crop production

    DEFF Research Database (Denmark)

    Jensen, Christian Richardt; Ørum, Jens Erik; Pedersen, Søren Marcus

    2014-01-01

    Agriculture is the main user of limited fresh water resources in the world. Optimisation of agricultural water resources and their use can be obtained by both agronomical and political incentives. Important options are: reduction of the loss of irrigation water in conveyance before it reaches...... of the 'virtual water' principles so that water-rich regions secure food supply to dry regions; reduction in waste of food, feed and biofuel from post-harvest to the end consumer; changing of food composition to less water-consuming products; regulating amount of irrigation water by rationing, subsidies or water...... pricing to support water-saving measures such as use of drip, irrigation scheduling and DI. The potential for water saving for different measures is discussed and estimated. Reduction in waste of food and loss of irrigation water from conveyance source to farm both has a great potential for water saving...

  8. An experimental study on the grape orchard: Effects comparison of two irrigation systems

    Directory of Open Access Journals (Sweden)

    Kadbhane Sharad J.

    2017-03-01

    Full Text Available Table grape (Vitis vinifera cultivars is a major cash crop in the Nashik district of India, which requires irrigation water throughout the year as per demand instantly. Canal irrigation is the adopted irrigation systems in the study area, but canal irrigation has got several serious disadvantages, such as mismatching rotation schedules and crop water demands, water allotment system and restrictions on the use of efficient irrigation methods. The storing the canal water in the farm pond instead of directly applying to the field using the free flooding method is alternate solution to overcome the disadvantages of the canal irrigation system. Once the canal water storing in the pond, it increases the possibilities to use the advance irrigation system like drip, subsurface, sprinkler etc. to enhance water use efficiency. The comparative study between the canal water directly applying for the field and canal water storing in the farm pond then use for irrigation, executed through the field experiments carried out on the grape orchard during a period April 2013 to March 2016. Results have been evaluated based on grape yield, water-productivity, berry size, and biomass. Water productivity (kg·m-3 with respect to water delivery to crop through the pond irrigation method was found 37% higher than the canal irrigation method during the study period. Based on the results, this study recommended the use of the farm pond to store the canal water and use it as per crop demand using advance irrigation systems.

  9. Use of plant woody species electrical potential for irrigation scheduling.

    Science.gov (United States)

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  10. Optimal simulation based design of deficit irrigation experiments

    OpenAIRE

    Seidel, Sabine

    2012-01-01

    There is a growing societal concern about excessive water and fertilizer use in agricultural systems. High water productivity while maintaining high crop yields can be achieved with appropriate irrigation scheduling. Moreover, freshwater pollution through nitrogen (N) leaching due to the widespread use of N fertilizers demands for an efficient N fertilization management. However, sustainable crop management requires good knowledge of soil water and N dynamics as well as of crop water and N de...

  11. Information Technology Supports Integration of Satellite Imagery with Irrigation Management in California's Central Valley

    Science.gov (United States)

    Remotely sensed data can potentially be used to develop crop coefficient estimates over large areas and make irrigation scheduling more practical, convenient, and accurate. A demonstration system is being developed under NASA's Terrestrial Observation and Prediction System (TOPS) to automatically r...

  12. Guidelines for irrigation scheduling of peach palm for heart-of-palm production in the São Francisco Valley, Brazil

    Directory of Open Access Journals (Sweden)

    Bassoi Luís Henrique

    2003-01-01

    Full Text Available The water consumption, crop coefficient and effective rooting depth of the peach palm cultivated in a Vertisol were evaluated over two years and three months, from planting to fifth harvest, in Juazeiro, Bahia State, Brazil. Plants were irrigated by microsprinklers under two irrigation treatments, full irrigation (FI and reduced irrigation (RI, and the amount of water applied in RI corresponded to 75% of that of FI. Water consumption and crop coefficient has increased markedly at the first harvest (7.3 mm day-1 and 1.2, respectively, in FI treatment in the thirteenth month, as a consequence of plant canopy development. After that, plants were harvested every three or four months, and these values varied a little due to decrease of the stand. The effective rooting depth was shallow (40 cm at 12 months (before the first harvest and it remained the same up to 24 months after planting (after the fourth harvest. Significant response of heart-of-palm yield to the irrigation treatments was not observed.

  13. More crop per drop: Improving our knowledge on crop water requirements for irrigation scheduling

    CSIR Research Space (South Africa)

    Gush, Mark B

    2015-10-01

    Full Text Available South Africa is a dry country facing climate change, population expansion and economic growth, resulting in increasing water scarcity and competition for water. The irrigated agriculture and forestry sectors have been allocated approximately two...

  14. Opportunities for Automated Demand Response in California Agricultural Irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Aghajanzadeh, Arian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McKane, Aimee [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    Pumping water for agricultural irrigation represents a significant share of California’s annual electricity use and peak demand. It also represents a large source of potential flexibility, as farms possess a form of storage in their wetted soil. By carefully modifying their irrigation schedules, growers can participate in demand response without adverse effects on their crops. This report describes the potential for participation in demand response and automated demand response by agricultural irrigators in California, as well as barriers to widespread participation. The report first describes the magnitude, timing, location, purpose, and manner of energy use in California. Typical on-­farm controls are discussed, as well as common impediments to participation in demand response and automated demand response programs. Case studies of demand response programs in California and across the country are reviewed, and their results along with overall California demand estimates are used to estimate statewide demand response potential. Finally, recommendations are made for future research that can enhance the understanding of demand response potential in this industry.

  15. Inhibition of tomato shoot growth by over-irrigation is linked to nitrogen deficiency and ethylene.

    Science.gov (United States)

    Fiebig, Antje; Dodd, Ian C

    2016-01-01

    Although physiological effects of acute flooding have been well studied, chronic effects of suboptimal soil aeration caused by over-irrigation of containerized plants have not, despite its likely commercial significance. By automatically scheduling irrigation according to soil moisture thresholds, effects of over-irrigation on soil properties (oxygen concentration, temperature and moisture), leaf growth, gas exchange, phytohormone [abscisic acid (ABA) and ethylene] relations and nutrient status of tomato (Solanum lycopersicum Mill. cv. Ailsa Craig) were studied. Over-irrigation slowly increased soil moisture and decreased soil oxygen concentration by 4%. Soil temperature was approximately 1°C lower in the over-irrigated substrate. Over-irrigating tomato plants for 2 weeks significantly reduced shoot height (by 25%) and fresh weight and total leaf area (by 60-70%) compared with well-drained plants. Over-irrigation did not alter stomatal conductance, leaf water potential or foliar ABA concentrations, suggesting that growth inhibition was not hydraulically regulated or dependent on stomatal closure or changes in ABA. However, over-irrigation significantly increased foliar ethylene emission. Ethylene seemed to inhibit growth, as the partially ethylene-insensitive genotype Never ripe (Nr) was much less sensitive to over-irrigation than the wild type. Over-irrigation induced significant foliar nitrogen deficiency and daily supplementation of small volumes of 10 mM Ca(NO3 )2 to over-irrigated soil restored foliar nitrogen concentrations, ethylene emission and shoot fresh weight of over-irrigated plants to control levels. Thus reduced nitrogen uptake plays an important role in inhibiting growth of over-irrigated plants, in part by stimulating foliar ethylene emission. © 2015 Scandinavian Plant Physiology Society.

  16. Soil water sensing: Implications of sensor capabilities for variable rate irrigation management

    Science.gov (United States)

    Irrigation scheduling using soil water sensors aims at maintaining the soil water content in the crop root zone above a lower limit defined by the management allowed depletion (MAD) for that soil and crop, but not so wet that too much water is lost to deep percolation, evaporation and runoff or that...

  17. Optimized Subsurface Irrigation System: The Future of Sugarcane Irrigation

    Directory of Open Access Journals (Sweden)

    M. H. J. P. Gunarathna

    2018-03-01

    Full Text Available Climate change may harm the growth and yield of sugarcane (Saccharum officinarum L. without the introduction of appropriate irrigation facilities. Therefore, new irrigation methods should be developed to maximize water use efficiency and reduce operational costs. OPSIS (optimized subsurface irrigation system is a new solar-powered automatic subsurface irrigation system that creates a phreatic zone below crop roots and relies on capillarity to supply water to the root zone. It is designed for upland crops such as sugarcane. We investigated the performance of OPSIS for irrigating sugarcane and evaluated its performance against sprinkler irrigation under subtropical conditions. We conducted field experiments in Okinawa, Japan, over the period from 2013 to 2016 and took measurements during spring- and summer-planted main crops and two ratoon crops of the spring-planted crop. Compared with sprinkler irrigation, OPSIS produced a significantly higher fresh cane yield, consumed less irrigation water and provided a higher irrigation water use efficiency. We conclude that OPSIS could be adopted as a sustainable solution to sugarcane irrigation in Okinawa and similar environments.

  18. Declining groundwater level caused by irrigation to row crops in the Lower Mississippi River Basin, Current Situation and Trends

    Science.gov (United States)

    Feng, G.; Gao, F.; Ouyang, Y.

    2017-12-01

    The Mississippi River is North America's largest river and the second largest watershed in the world. It flows over 3,700 km through America's heartland to the Gulf of Mexico. Over 3 million hectares in the Lower Mississippi River Basin represent irrigated cropland and 90 percent of those lands currently rely on the groundwater supply. The primary crops grown in this region are soybean, corn, cotton, and rice. Increased water withdrawals for irrigating those crops and stagnant recharging jeopardize the long-term availability of the aquifer and place irrigation agriculture in the region on an unsustainable path. The objectives of this study were to: 1) analyze the current groundwater level in the Lower Mississippi River Basin based on the water table depth observed by Yazoo Mississippi Delta Joint Water Management District from 2000 and 2016; 2) determine trends of change in groundwater level under conventional and groundwater saving irrigation management practices (ET or soil moisture based full irrigation scheduling using all groundwater or different percentages of ground and surface water). The coupled SWAT and MODFLOW model was applied to investigate the trends. Observed results showed that the groundwater level has declined from 33 to 26 m at an annual decrease rate of 0.4 m in the past 17 years. Simulated results revealed that the groundwater storage was decreased by 26 cm/month due to irrigation in crop season. It is promising that the groundwater storage was increased by 23 cm/month, sometimes even 60 cm/month in crop off-growing season because of recharge from rainfall. Our results suggest that alternative ET or soil moisture based groundwater saving irrigation scheduling with conjunctive use of surface water is a sustainable practice for irrigated agriculture in in the Lower Mississippi River Basin.

  19. Drip and Surface Irrigation Water Use Efficiency of Tomato Crop Using Nuclear Techniques

    International Nuclear Information System (INIS)

    Mellouli, H.J.; Askri, H.; Mougou, R.

    2003-01-01

    Nations in the arid and semi-arid regions, especially the Arab countries, will have to take up an important challenge at the beginning of the 21 st century: increasing food production in order to realise food security for growing population, wile optimising the use of limited water resources. Using and adapting management techniques like the drip irrigation system could obtain the later. This would allow reduction in water losses by bare soil evaporation and deep percolation. Consequently improved water use efficiency could be realised. In this way, this work was conducted as a contribution on the Tunisian national programs on the optimisation of the water use. By mean a field study at Cherfech Experimental Station (30 km from Tunis), the effect of the irrigation system on the water use efficiency (WUE)-by a season tomato crop-was monitored by comparing three treatments receiving equivalent quantities of fertiliser: Fertigation, Drip irrigation and Furrow irrigation. Irrigation was scheduled by mean calculation of the water requirement based on the agro meteorological data, the plant physiological stage and the soil water characteristics (Clay Loam). The plant water consumption (ETR) was determined by using soil water balance method, where rainfall and amount of irrigation water readily measured

  20. Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching.

    Directory of Open Access Journals (Sweden)

    Yaming Zhai

    Full Text Available To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt, quality, irrigation water use efficiency (IWUE and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1, 320 mm (W2 and 360 mm (W3, and the salinity levels were 1.0 dS/m (F, 3.0 dS/m (S1 and 5.0 dS/m (S2. Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym. After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual, and was recommended as the saline water irrigation scheme for tomatoes in northern China.

  1. Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching.

    Science.gov (United States)

    Zhai, Yaming; Yang, Qian; Wu, Yunyu

    2016-01-01

    To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt), quality, irrigation water use efficiency (IWUE) and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1), 320 mm (W2) and 360 mm (W3), and the salinity levels were 1.0 dS/m (F), 3.0 dS/m (S1) and 5.0 dS/m (S2). Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm) of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym). After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual), and was recommended as the saline water irrigation scheme for tomatoes in northern China.

  2. Apical negative pressure irrigation versus syringe irrigation: a systematic review of cleaning and disinfection of the root canal system.

    Science.gov (United States)

    Konstantinidi, E; Psimma, Z; Chávez de Paz, L E; Boutsioukis, C

    2017-11-01

    The aim of this study was to systematically review and critically analyse the published data on the treatment outcome (primary outcome) and on the cleaning and disinfection of root canals (secondary outcomes) achieved by negative pressure irrigation as compared to syringe irrigation. An electronic search was conducted in EMBASE, LILACS, PubMed, SciELO, Scopus and Web of Knowledge using both free-text keywords and controlled vocabulary. Additional studies were sought through hand searching of endodontic journals and of the relevant chapters of endodontic textbooks. No language restriction was imposed. The retrieved studies were screened by two reviewers according to predefined criteria. Included studies were critically appraised and the extracted data were arranged in tables. The electronic search and hand search retrieved 489 titles. One clinical study and 14 in vitro studies were finally included in the review; none of these studies assessed treatment outcome, four studies assessed the antimicrobial effect, seven studies evaluated the removal of pulp tissue remnants, and four studies investigated the removal of hard tissue debris or both hard tissue debris and pulp tissue remnants. Poor standardization and description of the protocols was evident. Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods. Negative pressure irrigation was more effective under certain conditions when compared to suboptimal syringe irrigation; however, the variability of the protocols hindered quantitative synthesis. There is insufficient evidence to claim general superiority of any one of these methods. The level of the available evidence is low, and the conclusions should be interpreted with caution. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  3. Leaching of N-nitrosodimethylamine (NDMA) in turfgrass soils during wastewater irrigation.

    Science.gov (United States)

    Gan, J; Bondarenko, S; Ernst, F; Yang, W; Ries, S B; Sedlak, D L

    2006-01-01

    N-nitrosodimethylamine (NDMA) is a carcinogenic by-product of chlorination that is frequently found in municipal wastewater effluent. NDMA is miscible in water and negligibly adsorbed to soil, and therefore may pose a threat to ground water when treated wastewater is used for landscape irrigation. A field study was performed in the summer months under arid Southern California weather conditions to evaluate the leaching potential of NDMA in turfgrass soils during wastewater irrigation. Wastewater was used to irrigate multiple turfgrass plots at 110 to 160% evapotranspiration rate for about 4 mo, and leachate was continuously collected and analyzed for NDMA. The treated wastewater contained relatively high levels of NDMA (114-1820 ng L(-1); mean 930 ng L(-1)). NDMA was detected infrequently in the leachate regardless of the soil type or irrigation schedule. At a method detection limit of 2 ng L(-1), NDMA was only detected in 9 out of 400 leachate samples and when it was detected, the NDMA concentration was less than 5 ng L(-1). NDMA was relatively persistent in the turfgrass soils during laboratory incubation, indicating that mechanisms other than biotransformation, likely volatilization and/or plant uptake, contributed to the rapid dissipation. Under conditions typical of turfgrass irrigation with wastewater effluent it is unlikely that NDMA will contaminate ground water.

  4. Estimating the own-price elasticity of demand for irrigation water in the Musi catchment of India

    Science.gov (United States)

    Davidson, Brian; Hellegers, Petra

    2011-10-01

    SummaryAs irrigation water is an input into a production process, its demand must be 'derived'. According to theory, a derived demand schedule should be downward sloping and dependent on the outputs produced from it, the prices of other inputs and the price of the water itself. Problems arise when an attempt is made to estimate the demand for irrigation water and the resulting own-price elasticity of demand, as the uses to which water is put are spatially, temporarily and geographically diverse. Because water is not generally freely traded, what normally passes for an estimate of the own-price elasticity of demand for irrigation water is usually a well argued assumption or an estimate that is derived from a simulation model of a hypothesized producer. Such approaches tend to provide an inadequate explanation of what is an extremely complex and important relationship. An adequate explanation of the relationship between the price and the quantity demanded of water should be one that not only accords with the theoretical expectations, but also accounts for the diversity of products produced from water (which includes the management practices of farmers), the seasons in which it is used and over the region within which it is used. The objective in this article is to present a method of estimating the demand curve for irrigation water. The method uses actual field data which is collated using the Residual Method to determine the value of the marginal product of water deployed over a wide range of crops, seasons and regions. These values of the marginal products, all which must lie of the input demand schedule for water, are then ordered from the highest value to the lowest. Then, the amount of irrigation water used for each product, in each season and in each region is cumulatively summed over the range of uses according to the order of the values of the marginal products. This data, once ordered, is then used to econometrically estimate the demand schedule from which

  5. Estimating the Own-Price Elasticity for Irrigation Water in the Musi Catchment of India

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.; Davidson, B.

    2011-01-01

    As irrigation water is an input into a production process, its demand must be ‘derived’. According to theory, a derived demand schedule should be downward sloping and dependent on the outputs produced from it, the prices of other inputs and the price of the water itself. Problems arise when an

  6. Fluid regimens for colostomy irrigation: a systematic review.

    Science.gov (United States)

    Lizarondo, Lucylynn; Aye Gyi, Aye; Schultz, Tim

    2008-09-01

    Background  Various techniques for managing faecal evacuation have been proposed; however, colostomy irrigation is favoured as it leads to better patient outcomes. Alternative fluid regimens for colostomy irrigation have been suggested to achieve effective evacuation. Aim  The objective of this review was to summarise the best available evidence on the most effective fluid regimen for colostomy irrigation. Search strategy  Trials were identified by electronic searches of CINAHL, PubMed, MEDLINE, Current Contents, the Cochrane Library and EMBASE. Unpublished articles and references lists from included studies were also searched. Selection criteria  Randomised controlled trials and before-and-after studies investigating any fluid regimen for colostomy irrigation were eligible for inclusion. Outcomes measured included fluid inflow time, total wash-out time, haemodynamic changes during irrigation, cramps, leakage episodes, quality of life and level of satisfaction. Data collection and analysis  Trial selection, quality appraisal and data extraction were carried out independently by two reviewers. Differences in opinion were resolved by discussion. Main results  The systematic literature search strategy identified two cross-over trials that compared water with another fluid regimen. Owing to the differences in irrigating solutions used, the results were not pooled for analysis. Both the polyethylene glycol electrolyte solution and glyceryl trinitrate performed significantly better than water. Conclusion  There is some evidence to support the effectiveness of fluid regimens other than water, such as polyethylene glycol electrolyte and glyceryl trinitrate, for colostomy irrigation. Further well-designed clinical trials are required to establish solid evidence on the effectiveness of other irrigating solutions that might enhance colonic irrigation. © 2008 The Authors. Journal Compilation © Blackwell Publishing Asia Pty Ltd.

  7. AUTOMATED IRRIGATION SYSTEM CONSTITUTED OF ELECTRONIC ELEMENTS, MOBILE DEVICE AND THE CONSTRUCTION OF SPRINKLER

    Directory of Open Access Journals (Sweden)

    Alma Delia González

    2017-12-01

    Full Text Available This document presents the development of an automated irrigation system, which consisted of a sprinkler that has a range of 16 meters in diameter using only sprinklers per one hectare of land, water pump, hose, water containers, electro valves, relays, electronic components such as humidity and temperature sensor, ultrasonic sensor, LCD screen, microcontroller (Arduino Mega, for communication a bluetooth module and a mobile device (Android. The agile methodology used was Extreme XP Programming, following its 4 phases, planning, design, development and testing. With this an automated irrigation system was used that was developed to monitor temperature, humidity and to generate a saving in the water thanks to the census of the container of the same, as well as the reduction of maintenance costs, this can be activated or deactivated by the user regardless of the conditions. The system complies with the characteristics of a utility model, because these models are all those objects, tools, appliances or tools that, as a result of a change in their layout, configuration, structure or form, present a different function with respect to the parts that integrate it or advantages in terms of its usefulness and thanks to the search carried out in IMPI. In the study of the state of the art the search was made in the data bases of Mexico in SIGA (Information System of the Gazette of the Industrial Property and internationally in Thomson, the results showed that there were similar sy

  8. Roles of the combined irrigation, drainage, and storage of the canal network in improving water reuse in the irrigation districts along the lower Yellow River, China

    Science.gov (United States)

    Liu, Lei; Luo, Yi; He, Chansheng; Lai, Jianbin; Li, Xiubin

    2010-09-01

    SummaryThe commonly used irrigation system in the irrigation districts (with a combined irrigation area of 3.334 × 10 6 ha) along the lower Yellow River of China is canal network. It delivers water from the Yellow River to the fields, collects surface runoff and drainage from cropland, and stores both of them for subsequent irrigation uses. This paper developed a new combined irrigation, drainage, and storage (CIDS) module for the SWAT2000 model, simulated the multiple roles of the CIDS canal system, and estimated its performance in improving water reuse in the irrigation districts under different irrigation and water diversion scenarios. The simulation results show that the annual evapotranspiration (ET) of the double-cropping winter wheat and summer maize was the highest under the full irrigation scenario (automatic irrigation), and the lowest under the no irrigation scenario. It varied between these two values when different irrigation schedules were adopted. Precipitation could only meet the water requirement of the double-cropping system by 62-96% on an annual basis; that of the winter wheat by 32-36%, summer maize by 92-123%, and cotton by 87-98% on a seasonal basis. Hence, effective irrigation management for winter wheat is critical to ensure high wheat yield in the study area. Runoff generation was closely related to precipitation and influenced by irrigation. The highest and lowest annual runoff accounted for 19% and 11% of the annual precipitation under the full irrigation and no irrigation scenarios, respectively. Nearly 70% of the annual runoff occurred during months of July and August due to the concentrated precipitation in these 2 months. The CIDS canals play an important role in delivering the diversion water from the Yellow River, intercepting the surface runoff and drainage from cropland (inflow of the CIDS canal) and recharging the shallow aquifer for later use. Roughly 14-26% of the simulated total flow in the CIDS canal system recharged

  9. Condensation irrigation a system for desalination and irrigation

    International Nuclear Information System (INIS)

    Lindblom, J.; Nordell, B

    2006-01-01

    condensation irrigation is a system for both desalination and irrigation. The principles is that humidified air is let into an underground horizontal pipe system, where the air is cooled by the ground and humidity falls out as fresh water. The humidification could e.g. be achieved by evaporation of seawater in solar stills or any other heat source. By using drainage pipes for underground air transportation the water percolates into the soil, thereby irrigating the land. This study focuses on drinking water production, which means that humid air is led into plan pipes where the condensed water is collected at the pipe endings. Numerical simulations gave a study-state diurnal mean water production of 1.8 kg per meter of pipe over a 50 m pipe. Shorter pipes result in a greater mean production rate. Since the heat transfer of drainage pipes would be greater, current study indicates that condensation irrigation is a promising method for desalination and irrigation. Performed studies in condensation irrigation started at LTU in 2003. Current paper reports the initial theoretical work on the system.(Author)

  10. Review of ultrasonic irrigation in endodontics: increasing action of irrigating solutions

    Science.gov (United States)

    Mozo, Sandra; Llena, Carmen

    2012-01-01

    Introduction: Effective irrigant delivery and agitation are prerequisites for successful endodontic treatment. Ultrasonic irrigation can be performed with or without simultaneous ultrasonic instrumentation. Existing literature reveals that ultrasonic irrigation may have a very positive effect on chemical, biological and physical debridement of the root canal system as investigated in many in vitro studies. Objective: The purpose of this review article was to summarize and discuss the available information concerning ultrasonic irrigation in endodontics. Methods: This article presents an overview of ultrasonic irrigation methods and their debridement efficacy. In this paper the relevant literature on passive ultrasonic irrigation is reviewed. Information from original scientific papers or reviews listed in MEDLINE and Cochrane were included in the review. Results: The use of ultrasound in the irrigation procedure results in improved canal cleanliness, better irrigant transfer to the canal system, soft tissue debridement, and removal of smear layer and bacteria. There are many in vitro studies, but there is a need to standardize protocols, and correlate the clinical efficacy of ultrasonic devices with improved treatment outcomes. Understanding the basis of ultrasonic irrigation is fundamental for clinicians and researchers to improve the design and use of ultrasonic irrigation. Key words:Ultrasonic irrigation, ultrasound, smear layer, endodontics. PMID:22143738

  11. Application of an infrared thermometer to the determination of the timing of irrigation

    International Nuclear Information System (INIS)

    Cho, T.; Yano, T.; Nakano, Y.

    1986-01-01

    It is well known that leaf temperature rises with increased crop water stress. This phenomenon is recognized as having the potential to yield information on irrigation scheduling. In this study, infrared thermometry was used to measure crop temperature remotely. The errors in measurements derived from incoming long-wave radiation and leaf emissivity were experimentally evaluated in relation to the reliability of three types of water stress indices using leaf temperature as the parameter. From consecutive measurements of the crop-air temperature difference, obvious changes in daily pattern could be detected as soil water became limited. This result showed that the crop-air temperature difference, although a simple index, can be used in irrigation timing

  12. Irrigation and Autocracy

    DEFF Research Database (Denmark)

    Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

    We show that societies with a history of irrigation-based agriculture have been less likely to adopt democracy than societies with a history of rainfed agriculture. Rather than actual irrigation, the empirical analysis is based on how much irrigation potentially can increase yields.Irrigation pot...

  13. Deficit irrigation of a landscape halophyte for reuse of saline waste water in a desert city

    Science.gov (United States)

    Glenn, E.P.; Mckeon, C.; Gerhart, V.; Nagler, P.L.; Jordan, F.; Artiola, J.

    2009-01-01

    Saline waste waters from industrial and water treatment processes are an under-utilized resource in desert urban environments. Management practices to safely use these water sources are still in development. We used a deeprooted native halophyte, Atriplex lentiformis (quailbush), to absorb mildly saline effluent (1800 mg l-1 total dissolved solids, mainly sodium sulfate) from a water treatment plant in the desert community of Twentynine Palms, California. We developed a deficit irrigation strategy to avoid discharging water past the root zone to the aquifer. The plants were irrigated at about one-third the rate of reference evapotranspiration (ETo) calculated from meteorological data over five years and soil moisture levels were monitored to a soil depth of 4.7 m at monthly intervals with a neutron hydroprobe. The deficit irrigation schedule maintained the soil below field capacity throughout the study. Water was presented on a more or less constant schedule, so that the application rates were less than ETo in summer and equal to or slightly greater than ETo in winter, but the plants were able to consume water stored in the profile in winter to support summer ET. Sodium salts gradually increased in the soil profile over the study but sulfate levels remained low, due to formation of gypsum in the calcic soil. The high salt tolerance, deep roots, and drought tolerance of desert halophytes such as A. lentiformis lend these plants to use as deficit-irrigated landscape plants for disposal of effluents in urban setting when protection of the aquifer is important. ?? 2008 Elsevier B.V.

  14. Drip irrigation using a PLC based adaptive irrigation system

    OpenAIRE

    Shahidian, S.; Serralheiro, R. P.; Teixeira, J. L.; Santos, F. L.; Oliveira, M. R. G.; Costa, J. L.; Toureiro, C.; Haie, Naim; Machado, R. M.

    2009-01-01

    Most of the water used by man goes to irrigation. A major part of this water is used to irrigate small plots where it is not feasible to implement full-scale Evapotranspiration based irrigation controllers. During the growth season crop water needs do not remain constant and varies depending on the canopy, growth stage and climate conditions such as temperature, wind, relative humidity and solar radiation. Thus, it is necessary to find an economic irrigation controller that can adapt the dail...

  15. Influence of irrigation during the growth stage on yield and quality in mango (Mangifera indica L).

    Science.gov (United States)

    Wei, Junya; Liu, Guoyin; Liu, Debing; Chen, Yeyuan

    2017-01-01

    Although being one of the few drought-tolerant plants, mango trees are irrigated to ensure optimum and consistent productivity in China. In order to better understand the effects of soil water content on mango yield and fruit quality at fruit growth stage, irrigation experiments were investigated and the object was to determine the soil water content criteria at which growth and quality of mango would be optimal based on soil water measured by RHD-JS water-saving irrigation system through micro-sprinkling irrigation. Five soil water content treatments (relative to the percentage of field water capacity) for irrigation (T1:79%-82%, T2:75%-78%, T3:71%-74%, T4: 65%-70%, T5:63%-66%) were compared in 2013. Amount of applied irrigation water for different treatments varied from 2.93m3 to 1.08 m3. The results showed that mango fruit production and quality at fruit growth stage were significantly affected under different irrigation water amounts. Variation in soil water content not only had effects on fruit size, but also on fruit yield. The highest fruit yield and irrigation water use efficiency were obtained from the T4 treatment. Irrigation water amount also affected fruit quality parameters like fruit total soluble solids, soluble sugar, starch, titratable acid and vitamin C content. Comprehensive evaluation of the effect of indexs of correlation on irrigation treatment by subordinate function showed that when the soil moisture content were controlled at about 65-70% of the field water moisture capacity, water demand in the growth and development of mango could be ensured, and maximum production efficiency of irrigation and the best quality of fruit could be achieved. In conclusion, treatment T4 was the optimum irrigation schedule for growing mango, thus achieving efficient production of mango in consideration of the compromise among mango yield, fruit quality and water use efficiency.

  16. The relationship between sap flow and commercial soil water sensor readings in irrigated potato (Solanum tuberosum L.) production

    Science.gov (United States)

    Many irrigation scheduling methods utilized in commercial production settings rely on soil water sensors that are normally purchased as off-the-shelf technology or through contracted services that install and monitor readings throughout the season. These systems often assume a direct relationship be...

  17. Gas Exchanges and Stem Water Potential Define Stress Thresholds for Efficient Irrigation Management in Olive (Olea europea L.

    Directory of Open Access Journals (Sweden)

    Giulia Marino

    2018-03-01

    Full Text Available With climate change and decreased water supplies, interest in irrigation scheduling based on plant water status is increasing. Stem water potential (ΨSWP thresholds for irrigation scheduling in olive have been proposed, however, a physiologically-based evaluation of their reliability is needed. A large dataset collected at variable environmental conditions, growing systems, and genotypes was used to characterize the relation between ΨSWP and gas exchanges for olive. Based on the effect of drought stress on the ecophysiological parameters monitored, we described three levels of stress: no stress (ΨSWP above about −2 MPa, where the high variability of stomatal conductance (gs suggests a tight stomatal control of water loss that limit ΨSWP drop, irrigation volumes applied to overcome this threshold had no effect on assimilation but reduced intrinsic water use efficiency (iWUE; moderate-stress (ΨSWP between about −2.0 and −3.5 MPa, where iWUE can be increased without damage to the photosynthetic apparatus of leaves; and high-stress (ΨSWP below about −3.5 MPa, where gs dropped below 150 mmol m−2 s−1 and the intercellular CO2 concentration increased proportionally, suggesting non-stomatal limitation to photosynthesis was operative. This study confirmed that olive ΨSWP should be maintained between −2 and −3.5 MPa for optimal irrigation efficiency and to avoid harmful water stress levels.

  18. Operational Space-Assisted Irrigation Advisory Services: Overview Of And Lessons Learned From The Project DEMETER

    Science.gov (United States)

    Osann Jochum, M. A.; Demeter Partners

    2006-08-01

    The project DEMETER (DEMonstration of Earth observation TEchnologies in Routine irrigation advisory services) was dedicated to assessing and demonstrating improvements introduced by Earth observation (EO) and Information and Communication Technologies (ICT) in farm and Irrigation Advisory Service (IAS) day-to-day operations. The DEMETER concept of near-real-time delivery of EO-based irrigation scheduling information to IAS and farmers has proven to be valid. The operationality of the space segment was demonstrated for Landsat 5-TM in the Barrax pilot zone during the 2004 and 2005 irrigation campaigns. Extra-fast image delivery and quality controlled operational processing make the EO-based crop coefficient maps available at the same speed and quality as ground-based data (point samples), while significantly extending the spatial coverage and reducing service cost. Leading-edge online analysis and visualization tools provide easy, intuitive access to the information and personalized service to users. First feedback of users at IAS and farmer level is encouraging. The paper gives an overview of the project and its main achievements.

  19. Water Use and Crop Coefficients in Sprinkler Irrigated Rice

    Directory of Open Access Journals (Sweden)

    Antonino Spanu

    Full Text Available Field experiments were carried out during the years 2002, 2004, 2005 and 2006 to analyze water-soil-atmosphere interactions in sprinkler irrigated rice. The research was carried out in Sardinia (39º 59’ N; 8º 40’ E, at altitude 15 m. The cultivars used in the experiments, respectively in 2002 and in 2004-2005-2006, were Irat 212 and Eurosis. In each year cultivars were subjected to the same crop management. Irrigation was applied since the emergence with the sprinkler method, taking into account the loss of water from ‘Class A’ pan evaporation. Soil water content was monitored at 0.10 m intervals until 1.00-m depth using a ‘Diviner 2000’ (Sentek. In 2002 seven irrigation scheduling treatments were compared. In 2004, 2005, 2006 irrigation treatments provided for optimal soil water conditions during the growing season. In 2002 the results highlighted: 1 0-0.20 m depth was the most important layer for crop water uptake and the best correlated layer with rice rough yield; 2 the positive relationship between yield and water supply was significant until 6500 m3 ha-1 of water applied. Further seasonal irrigation volumes did not increase significantly yield. In 2004, 2005 and 2006 the analysis of the soil water balance at different crop phenological stages allowed to estimate crop coefficients (Kc using the Penman-Monteith equation and the ‘Class A’ pan evaporation (Kcev. Kc varied over the three-year period on average from 0.90 to 1.07 and 0.97, respectively for the emergence-end of tillering, end of tillering-heading and heading-maturing periods, while crop coefficients as a ratio between maximum crop evapotranspiration (ETc and Epan, Kcev ranged from 0.78 to 0.92 and 0.81 for the same time periods.

  20. Effect of Timing and Amount of Irrigation Water on Bean Yield and Water Use Efficiency in Arid and Semi-arid Conditions

    Directory of Open Access Journals (Sweden)

    S.S. Nurbakhsh

    2016-02-01

    Full Text Available Introduction: Nowadays, due to lack of water resources and increasing demand for water, agricultural water planning issues need further consideration. With proper planning and determination of irrigation depth and time, the effects of stress and yield loss on the plants are reduced. Irrigation scheduling is one of the most important factors in crop’s quality and quantity. The main objective of irrigation scheduling is to control crop’s water conditions in order to achieve its optimum yield level. So irrigation timing is the vital factor on which crop water stress and eventually yield's level are dependent upon. Moreover, irrigation timing is used in irrigation scheduling. The aim of this study was to evaluate the effect of irrigation time on water consumption, water use efficiency and yield of beans. Materials and Methods: In order to observe the effect of the amount and the time of the irrigation on water consumption, yields rate and water use efficiency, the current research was carried out at the University of Shahrekord during the summer of 2012. The experiment was done as a completely randomized design with 4 repetitions consisting of irrigation time and the amount of irrigation in 4 and 2 levels (at 6, 8, 14 and 18 and (deficit irrigation, full irrigation, respectively. Beans seeds were planted in 32 similar vases with a diameter of 45 cm and height of 60 cm, in each experiment. Treatments were begun after 37 days from planting. Treatments were irrigated when the average moisture in the root zone was equal to the lower border of readily available water of full irrigation. At the end of the experiments, plants were completely harvested. Then the plant’s height, number of branches, numbers of pods per plant, pod and seed weight were measured. Results and Discussion: Results showed that irrigating at different times during the day influenced water use efficiency, water consumption, seeds yield and number of pods in the bush. The water

  1. Impacts of Irrigation Practices on Groundwater Recharge in Mississippi Delta Using coupled SWAT-MODFLOW Model

    Science.gov (United States)

    Gao, F.; Feng, G.; Han, M.; Jenkins, J.; Ouyang, Y.

    2017-12-01

    The Lower Mississippi River alluvial plain (refers to as MS Delta), located in the northwest state of Mississippi, is one of the most productive agricultural region in the U.S. The primary crops grown in this region are soybean, corn, cotton, and rice. Approximately 80% water from the alluvial aquifer in MS Delta are withdrawn for irrigation, which makes it the most used aquifer in the State. As a result, groundwater level has declined > 6 m since 1970, which threaten the sustainability of irrigated agriculture in this region. The objectives of this study were to: 1) couple the SWAT and MODFLOW then calibrate and validate the incorporated model outputs for stream flow, groundwater level and evapotranspiration (ET) in MS Delta; 2) simulate the groundwater recharge as affected by a) conventional irrigation scheme, b) no irrigation scheme, c) ET based and soil moisture based full irrigation schedules using all groundwater, and d) ET and soil moisture based full irrigation schedule using different percentages of surface and ground water. Results indicated that the coupled model performed well during the calibration and validation for daily stream flow at three USGS gauge stations. (R2=0.7; Nash-Sutcliffe efficiency (NSE) varied from 0.6 to 0.7; Root Mean Square Error (RMSE) ranged from 20 to 27 m3/s). The values of determination coefficient R2 for groundwater level were 0.95 for calibration and 0.88 for validation, their NSE values were 0.99 and 0.93, respectively. The values of RMSE for groundwater level during the calibration and validation period were 0.51 and 0.59 m. The values of R2, NSE and RMSE between SWAT-MODFLOW simulated actual evapotranspiration (ET) and remote sensing evapotranspiration (ET) were 0.52, 0.51 and 28.1 mm. The simulated total average monthly groundwater recharge had lower values of 19 mm/month in the crop season than 30 mm/month in the crop off-growing season. The SWAT-MODFLOW can be a useful tool for not only simulating the recharge in MS

  2. ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

    OpenAIRE

    Aniketh; Mohamed; Geeta; Nandakishore; Gourav Kumar; Patrick Timothy; Jayson Mathew; Sahle Abdul

    2015-01-01

    Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and con...

  3. Effect of different levels of nitrogen fertilizer on yield and quality of sugar beet Beta vulgaris irrigated with saline groundwater (fertigation and surface irrigation) and grown under saline conditions

    International Nuclear Information System (INIS)

    Janat, M.

    2009-07-01

    In a field experiment Sugar beet Beta vulgaris was grown as a spring crop during the growing seasons of 2004 and 2006, in salt affected soil, previously planted with sesbania and barley (2005 and 2003) to evaluate the response of sugar beet to two irrigation methods, (drip fertigation and surface irrigation), different levels of nitrogen fertilizer and its effect on yield and quality. Different rates of nitrogen fertilizers (0, 50, 100, 150 and 200 kg N/ ha) as urea (46% N) were injected for drip irrigation or broadcasted for the surface-irrigated treatments in four equally split applications. The 15 N labelled urea was applied to sub-plots of 1.0 m 2 in each experimental unit in a manner similar to that of unlabeled urea. Irrigation scheduling was carried out using the direct method of neutron scattering technique. Sugar beet was irrigated when soil moisture in the upper 25 cm was 80% of the field capacity (FC) and such practice continued until the six leaf stage. From the latter stage until harvest, sugar beet was irrigated when soil moisture in the upper 50 cm reached 80% of the FC. The amount of irrigation water applied, electrical conductivity of the soil paste, dry matter and fresh roots yield, total nitrogen uptake and N derived from fertilizer were also determined. Furthermore, Nitrogen use as well as water use-efficiencies for dry matter and roots yield were also calculated. Results revealed that sugar beets and dry matter yield increased with increasing N input up to 100-150 kg N/ha which was indicated by the higher dry matter yield, and sugar beet yield. Sugar percentage was also increased relative to the average percentage recorded in Syria. Crop water use efficiencies, for both the drip-fertigated and surface-irrigated treatments were increased in most cases with increasing rate of nitrogen fertilizer. During the course of this study, small increases in soil salinity under both irrigation methods were observed. Higher increases in soil salinity was

  4. Impact of climate change on irrigation management for olive orchards at southern Spain

    Science.gov (United States)

    Lorite, Ignacio; Gabaldón-Leal, Clara; Santos, Cristina; Belaj, Angjelina; de la Rosa, Raul; Leon, Lorenzo; Ruiz-Ramos, Margarita

    2017-04-01

    The irrigation management for olive orchards under future weather conditions requires the development of advanced tools for considering specific physiological and phenological components affected by the foreseen changes in climate and atmospheric [CO2]. In this study a new simulation model named AdaptaOlive has been considered to develop controlled deficit irrigation and full irrigation scheduling for the traditional olive orchards located in Andalusia region (southern Spain) under the projected climate generated by an ensemble of 11 climate models from the ENSEMBLES European project corresponding to the SRES A1B scenario. Irrigation requirements, irrigation water productivity (IWP) and net margin (NM) were evaluated for three periods (baseline, near future and far future) and three irrigation strategies (rainfed, RF, controlled deficit irrigation, CDI, and full irrigation, FI). For irrigation requirements, a very limited average increase for far future compared with baseline period was found (2.6 and 1.3%, for CDI and FI, respectively). Equally, when IWP was analyzed, significant increases were identified for both irrigation strategies (77.4 and 72.2%, for CDI and FI, respectively) due to the high simulated increase in yield. Finally, when net margin was analyzed, the irrigation water cost had a key significance. For low water costs FI provided higher net margin values than for CDI. However, for high water costs (expected in the future due to the foreseen reduction in rainfall and the increase of the competence for the available water resources), net margin is reduced significantly, generating a very elevated number of years with negative net margin. All the described results are affected by a high level of uncertainty as the projections from the ensemble of 11 climate models show large spread. Thus, for a representative location within Andalusia region as Baeza, a reduction of irrigation requirements under full irrigation strategy was found for the ensemble mean

  5. Analysis of Irrigation Water Quality at Kadawa Irrigation Project for Improved Productivity

    Directory of Open Access Journals (Sweden)

    AR Sanda

    2014-09-01

    Full Text Available In the face of water scarcity and the several negative consequences, such as water wastage, flooding, water logging, soil losses and production losses, conserving the finite amount of fresh water is a must. The quality of irrigation water must therefore be ascertained. The chemical quality of three sources of irrigation water from canal and drainage water, namely drainage water, fresh irrigation water from canal, and drainage/irrigation water mixture, were analyzed from Kadawa irrigation Project for year 2013 and 2014 cropping seasons, with the view to evaluating the potential risks associated with their use in irrigation and hence their suitability or otherwise for irrigation purposes. The analysis revealed that the use of drainage water alone for irrigation may result in problems associated with salinity, while a blend of drainage/irrigation water in the ratio of 1:1 is a viable means of water conservation and a good means of crop production. DOI: http://dx.doi.org/10.3126/ije.v3i3.11082 International Journal of Environment Vol.3(3 2014: 235-240

  6. Environmental surveillance master sampling schedule

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, L E

    1992-01-01

    Environmental surveillance of the Hanford Site and surrounding areas is conducted by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This document contains the planned schedule for routine sample collection for the Surface Environmental Surveillance Project (SESP) and Ground-Water Monitoring Project. Samples for radiological analyses include Air-Particulate Filter, gases and vapor; Water/Columbia River, Onsite Pond, Spring, Irrigation, and Drinking; Foodstuffs/Animal Products including Whole Milk, Poultry and Eggs, and Beef; Foodstuffs/Produce including Leafy Vegetables, Vegetables, and Fruit; Foodstuffs/Farm Products including Wine, Wheat and Alfalfa; Wildlife; Soil; Vegetation; and Sediment. Direct Radiation Measurements include Terrestrial Locations, Columbia River Shoreline Locations, and Onsite Roadway, Railway and Aerial, Radiation Surveys.

  7. Does colostomy irrigation affect functional outcomes and quality of life in persons with a colostomy?

    Science.gov (United States)

    Kent, Dea J; Long, Mary Arnold; Bauer, Carole

    2015-01-01

    Colostomy irrigation may be used by patients with colostomies to regulate bowel evacuations by stimulating emptying of the colon at regularly scheduled times. This Evidence-Based Report Card reviews the effect of colostomy irrigation on frequency of bowel evacuation, flatus production, odor, and health-related quality of life. We systematically reviewed the literature for studies that evaluated health-related quality of life in persons aged 18 years or older with colostomies of the sigmoid or descending left colon. A professional librarian performed the literature search, which yielded 499 articles using the search terms "colostomy," "colostomies," "therapeutic irrigation," "irrigation," and "irrigator." Following title and abstract reviews, we identified and retrieved 4 studies that met inclusion criteria. Colostomy irrigation reduces the frequency of bowel evacuations when compared to spontaneous evacuation and containment using a pouching system. Regular irrigation is associated with reductions in pouch usage. This change in bowel evacuation function frequently results in absence of bowel evacuations for 24 hours or longer, enabling some to discontinue ongoing use of a pouching system. Subjects using CI report reductions in flatus and odors associated with presence of a colostomy. One study was identified that found persons using CI reported higher health-related quality of life than did those who managed their colostomies with spontaneous evacuation using the Digestive Disease Quality of Life-15, but no differences were found when health-related quality of life was measured using the more generic instrument, the Medical Outcomes Study: Short Form-36. Instruction on principles and techniques of colostomy irrigation should be considered when managing patients with a permanent, left-sided colostomy.

  8. Green and blue water footprint reduction in irrigated agriculture: effect of irrigation techniques, irrigation strategies and mulching

    Science.gov (United States)

    Chukalla, A. D.; Krol, M. S.; Hoekstra, A. Y.

    2015-12-01

    Consumptive water footprint (WF) reduction in irrigated crop production is essential given the increasing competition for freshwater. This study explores the effect of three management practices on the soil water balance and plant growth, specifically on evapotranspiration (ET) and yield (Y) and thus the consumptive WF of crops (ET / Y). The management practices are four irrigation techniques (furrow, sprinkler, drip and subsurface drip (SSD)), four irrigation strategies (full (FI), deficit (DI), supplementary (SI) and no irrigation), and three mulching practices (no mulching, organic (OML) and synthetic (SML) mulching). Various cases were considered: arid, semi-arid, sub-humid and humid environments in Israel, Spain, Italy and the UK, respectively; wet, normal and dry years; three soil types (sand, sandy loam and silty clay loam); and three crops (maize, potato and tomato). The AquaCrop model and the global WF accounting standard were used to relate the management practices to effects on ET, Y and WF. For each management practice, the associated green, blue and total consumptive WF were compared to the reference case (furrow irrigation, full irrigation, no mulching). The average reduction in the consumptive WF is 8-10 % if we change from the reference to drip or SSD, 13 % when changing to OML, 17-18 % when moving to drip or SSD in combination with OML, and 28 % for drip or SSD in combination with SML. All before-mentioned reductions increase by one or a few per cent when moving from full to deficit irrigation. Reduction in overall consumptive WF always goes together with an increasing ratio of green to blue WF. The WF of growing a crop for a particular environment is smallest under DI, followed by FI, SI and rain-fed. Growing crops with sprinkler irrigation has the largest consumptive WF, followed by furrow, drip and SSD. Furrow irrigation has a smaller consumptive WF compared with sprinkler, even though the classical measure of "irrigation efficiency" for furrow

  9. Root canal irrigants

    OpenAIRE

    Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

    2010-01-01

    Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

  10. Project Schedule Simulation

    DEFF Research Database (Denmark)

    Mizouni, Rabeb; Lazarova-Molnar, Sanja

    2015-01-01

    overrun both their budget and time. To improve the quality of initial project plans, we show in this paper the importance of (1) reflecting features’ priorities/risk in task schedules and (2) considering uncertainties related to human factors in plan schedules. To make simulation tasks reflect features......’ priority as well as multimodal team allocation, enhanced project schedules (EPS), where remedial actions scenarios (RAS) are added, were introduced. They reflect potential schedule modifications in case of uncertainties and promote a dynamic sequencing of involved tasks rather than the static conventional...... this document as an instruction set. The electronic file of your paper will be formatted further at Journal of Software. Define all symbols used in the abstract. Do not cite references in the abstract. Do not delete the blank line immediately above the abstract; it sets the footnote at the bottom of this column....

  11. Testing an Irrigation Decision Support Tool for California Specialty Crops

    Science.gov (United States)

    Johnson, L.; Cahn, M.; Benzen, S.; Zaragoza, I.; Murphy, L.; Melton, F. S.; Martin, F.; Quackenbush, A.; Lockhart, T.

    2015-12-01

    Estimation of crop evapotranspiration supports efficiency of irrigation water management, which in turn can mitigate nitrate leaching, groundwater depletion, and provide energy savings. Past research in California and elsewhere has revealed strong relationships between photosynthetically active vegetation fraction (Fc) and crop evapotranspiration (ETc). Additional research has shown the potential of monitoring Fc by satellite remote sensing. The U.C. Cooperative Extension developed and operates CropManage (CM) as on-line database irrigation (and nitrogen) scheduling tool. CM accounts for the rapid growth and typically brief cycle of cool-season vegetables, where Fc and fraction of reference ET can change daily during canopy development. The model automates crop water requirement calculations based on reference ET data collected by California Dept. Water Resources. Empirically-derived equations are used to estimate daily Fc time-series for a given crop type primarily as a function of planting date and expected harvest date. An application programming interface (API) is under development to provide a check on modeled Fc of current crops and facilitate CM expansion to new crops. The API will enable CM to extract field scale Fc observations from NASA's Satellite Irrigation Management Support (SIMS). SIMS is mainly Landsat based and currently monitors Fc over about 8 million irrigation acres statewide, with potential for adding data from ESA/Sentinel for improved temporal resolution. In the current study, a replicated irrigation trial was performed on romaine lettuce at the USDA Agricultural Research Station in Salinas, CA. CropManage recommendations were used to guide water treatments by drip irrigation at 50%, 75%, 100% ETc replacement levels, with an added treatment at 150% ET representing grower standard practice. Experimental results indicate that yields from the 100% and 150% treatments were not significantly different and were in-line with industry average, while

  12. Effect of drip irrigation on yield, evapotranspiration and water use efficiency of sweet basil (Ocimum basilicum L.

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2017-01-01

    Full Text Available The experiments showing the effect of drip irrigation on yield, evapotranspiration and water productivity of sweet basil (Ocimum basilicum L. were conducted at the experimental field of the Alternative Crops Department, Institute of Field and Vegetable Crops, Novi Sad. Irrigation was scheduled on the basis of the water balance method. Daily evapotranspiration (ETd was computed from the reference evapotranspiration (ETo and crop coefficient (kc in May, June, July and August of 0.5, 0.6, 1.1 and 1.0, respectively. ETo was calculated using Hargreaves equation. The irrigation depth was restricted to the soil depth of 0.3 m. In other words, irrigation started when readily available water in the soil layer of 0.3 m was completely depleted by plants. The irrigation rate was 30 mm (30 l m-2 while the amount of water added by irrigation during the season was 140 mm. Basil sensitivity to water stress was determined using a yield response factor (Ky. According to the results, the yield of fresh herb of basil under irrigation (32.015 t ha-1 was higher by 9% compared to non-irrigated, control variant (29.364 t ha-1. Worthy of note, basil essential oil yield was significantly affected by irrigation (35.329/28.766 kg ha-1. The content of essential oil was significantly higher in irrigated (6.45 g kg-1 than in non-irrigated variant (5.33 g kg-1 in the first harvest, while no significant difference between irrigated and non-irrigated variants was obtained in the second harvest (6.83 and 6.62 g kg-1 , respectively. Water used on evapotranspiration in irrigation conditions (ETm was 431 mm and 270 mm in non-irrigated, control variant (ETa. The values of irrigation water use efficiency (Iwue and evapotranspiration water use efficiency (ETwue were 1.89 kg m-3 and 1.65 kg m-3 respectively. Ky value (0.22 exhibits all essential characteristics of climate conditions of 2016 rainy year. These preliminary results could be used as a good platform for basil growers in the

  13. Smart Irrigation From Soil Moisture Forecast Using Satellite And Hydro -Meteorological Modelling

    Science.gov (United States)

    Corbari, Chiara; Mancini, Marco; Ravazzani, Giovanni; Ceppi, Alessandro; Salerno, Raffaele; Sobrino, Josè

    2017-04-01

    Increased water demand and climate change impacts have recently enhanced the need to improve water resources management, even in those areas which traditionally have an abundant supply of water. The highest consumption of water is devoted to irrigation for agricultural production, and so it is in this area that efforts have to be focused to study possible interventions. The SIM project funded by EU in the framework of the WaterWorks2014 - Water Joint Programming Initiative aims at developing an operational tool for real-time forecast of crops irrigation water requirements to support parsimonious water management and to optimize irrigation scheduling providing real-time and forecasted soil moisture behavior at high spatial and temporal resolutions with forecast horizons from few up to thirty days. This study discusses advances in coupling satellite driven soil water balance model and meteorological forecast as support for precision irrigation use comparing different case studies in Italy, in the Netherlands, in China and Spain, characterized by different climatic conditions, water availability, crop types and irrigation techniques and water distribution rules. Herein, the applications in two operative farms in vegetables production in the South of Italy where semi-arid climatic conditions holds, two maize fields in Northern Italy in a more water reach environment with flood irrigation will be presented. This system combines state of the art mathematical models and new technologies for environmental monitoring, merging ground observed data with Earth observations. Discussion on the methodology approach is presented, comparing for a reanalysis periods the forecast system outputs with observed soil moisture and crop water needs proving the reliability of the forecasting system and its benefits. The real-time visualization of the implemented system is also presented through web-dashboards.

  14. Utilizing on-farm best management practices: Managing Nitrate Leaching Using Evapotranspiration Based Irrigation Methods

    Science.gov (United States)

    Zaragosa, I.; Melton, F. S.; Dexter, J.; Post, K.; Haffa, A.; Kortman, S.; Spellenberg, R.; Cahn, M.

    2017-12-01

    In efforts to provide tools to allow farmers to optimize and quantify water usage and fertilizer applications, University of California Cooperative Extension (UCCE) developed the CropManage irrigation and nitrogen scheduling tool that provides real time evapotranspiration (ETc) based irrigation recommendations and fertilizer recommendations on a per field basis. CropManage incorporates satellite based estimates of fractional cover from web data services from the Satellite Irrigation Management Information Support (SIMS) system developed by NASA Ames Research Center in collaboration with California State University Monterey Bay (CSUMB). In this study, we conducted field trials to quantify the benefits of using these tools to support best management practices (BMPs) for irrigation and nutrient management in strawberries and lettuce in the Salinas Valley, California. We applied two different irrigation treatments based on full replacement (100%) of crop evapotranspiration (ETc), and irrigation at 130% of ETc replacement to approximate irrigation under business as usual irrigation management. Both field studies used a randomized block design with four replicates each. We used CropManage to calculate the 100% and 130% ETc replacement requirements prior to each irrigation event. We collected drainage volume and samples and analyzed them for 8500 to nitrate as (NO3-) concentrations. Experimental results for both strawberries and lettuce showed a significant decrease in the percentage of applied nitrogen leached for the 100% ETc replacement treatment against the 130% ETc replacement treatment. For strawberries, we observed that 24% of applied nitrogen was leached under the 100% ETc replacement treatment, versus 51% of applied nitrogen that was leached under the 130% ETc replacement treatment. For lettuce, we observe that 2% of the applied nitrogen leached bellow the soil profile, versus 6% of the applied nitrogen for the 130%ETc replacement treatment. In both experiments

  15. Soil Water Balance and Irrigation Strategies in an Agricultural District of Southern Italy

    Directory of Open Access Journals (Sweden)

    Domenico Ventrella

    2010-06-01

    Full Text Available An efficient management of water resources is considered very important for Mediterranean regions of Italy in order to improve the economical and environmental sustainability of the agricultural activity. The purpose of this study is to analyze the components of soil water balance in an important district included in the regions of Basilicata and Puglia and situated in the Jonical coastal area of Southern Italy and mainly cropped with horticultural crops. The study was performed by using the spatially distributed and physically based model SIMODIS in order to individuate the best irrigation management maximizing the water use efficiency and minimizing water losses by deep percolation and soil evaporation. SIMODIS was applied taking in to account the soil spatial variability and localization of cadastral units for two crops, durum wheat and water melon. For water melon recognition in 2007 a remote sensed image, from SPOT5 satellite, at the spatial resolution of 10 m, has been used. In 2008, a multi-temporal data set was available, from SPOT5 satellite to produce a land cover map for the classes water melon and durum wheat. Water melon cultivation was simulated adopting different water supply managements: rainfed and four irrigation strategies based on (i soil water availability and (ii plant water status adopting a threshold daily stress value. For each management, several water management indicators were calculated and mapped in GIS environment. For seasonal irrigation depth, actual evapotranspiration and irrigation efficiency were also determined. The analysis allowed to individuate the areas particularly sensitive to water losses by deep percolation because of their hydraulic functions characterized by low water retention and large values of saturated hydraulic conductivity. For these areas, the irrigation based on plant water status caused very high water losses by drainage. On the contrary, the irrigation scheduled on soil base allowed to

  16. Evaluation of the effects of mulch on optimum sowing date and irrigation management of zero till wheat in central Punjab, India using APSIM.

    Science.gov (United States)

    Balwinder-Singh; Humphreys, E; Gaydon, D S; Eberbach, P L

    2016-10-01

    Machinery for sowing wheat directly into rice residues has become more common in the rice-wheat systems of the north-west Indo-Gangetic Plains of South Asia, with increasing numbers of farmers now potentially able to access the benefits of residue retention. However, surface residue retention affects soil water and temperature dynamics, thus the optimum sowing date and irrigation management for a mulched crop may vary from those of a traditional non-mulched crop. Furthermore, the effects of sowing date and irrigation management are likely to vary with soil type and seasonal conditions. Therefore, a simulation study was conducted using the APSIM model and 40 years of weather data to evaluate the effects of mulch, sowing date and irrigation management and their interactions on wheat grain yield, irrigation requirement (I) and water productivity with respect to irrigation (WP I ) and evapotranspiration (WP ET ). The results suggest that the optimum wheat sowing date in central Punjab depends on both soil type and the presence or absence of mulch. On the sandy loam, with irrigation scheduled at 50% soil water deficit (SWD), the optimum sowing date was late October to early November for maximising yield, WP I and WP ET . On the clay loam, the optimum date was about one week later. The effect of mulch on yield varied with seasonal conditions and sowing date. With irrigation at 50% SWD, mulching of wheat sown at the optimum time increased average yield by up to 0.5 t ha -1 . The beneficial effect of mulch on yield increased to averages of 1.2-1.3 t ha -1 as sowing was advanced to 15 October. With irrigation at 50% SWD and 7 November sowing, mulch reduced the number of irrigations by one in almost 50% of years, a reduction of about 50 mm on the sandy loam and 60 mm on the clay loam. The reduction in irrigation amount was mainly due to reduced soil evaporation. Mulch reduced irrigation requirement by more as sowing was delayed, more so on the sandy loam than the clay

  17. Technical Evaluation of Sprinkler Irrigation Systems which were Implemented in Tea Fields of the Guilan Province

    Directory of Open Access Journals (Sweden)

    kourosh majdsalimi

    2016-02-01

    Full Text Available Introduction: Designing and management of sprinkler irrigation systems depend on the situation and location of its implementation and often rely on professional and long-term tests (9. Having a good irrigation system depends on knowledge of the relationship between soil, water, plants, irrigation scheduling, the required amount of irrigation water to the water-holding capacity of soil, climate and plant growth (6.The less use of sprinkler irrigation systems and less performed research projects in the Guilan province, lack of correct design parameters due to shortage of the required parameters for local and regional planning, has led to reliance on charts and tables. Therefore, planning water resources cannot be performed well and with accurate details. According to many researchers (8, the technical evaluation should be a regular and short-term process to review the problems and possible performance of irrigation systems. Merriam and Keller (10 defined the assessment of an irrigation system analysis, based on field measurements in real terms during the normal work of the system. Therefore, to develop these systems over the next few years, it is essential to evaluate the use of irrigation systems and review the performance of existing problems and utilizing the results to improve it. The aim of this study was to assess the current status of implemented irrigation systems in the tea plantations of Guilan and evaluate their performance. Materials and Methods: In this study, six classic sprinkler irrigation systems in tea fields of Guilan province were evaluated during two years. Sprinkler irrigation systems of semi-portable, solid-set and solid-set (hand-move sprinkler were selected randomly. To evaluate this irrigation systems, Christiansen’s uniformity coefficient (CU, distribution uniformity (DU, potential application efficiency of low-quarter (PELQ and application efficiency of low-quarter (AELQ in the form of trial blocks were estimated by

  18. Evaluation of endothelial mucin layer thickness after phacoemulsification with next generation ophthalmic irrigating solution.

    Science.gov (United States)

    Ghate, Deepta A; Holley, Glenn; Dollinger, Harli; Bullock, Joseph P; Markwardt, Kerry; Edelhauser, Henry F

    2008-10-01

    To evaluate human corneal endothelial mucin layer thickness and ultrastructure after phacoemulsification and irrigation-aspiration with either next generation ophthalmic irrigating solution (NGOIS) or BSS PLUS. Paired human corneas were mounted in an artificial anterior chamber, exposed to 3 minutes of continuous ultrasound (US) at 80% power using the Alcon SERIES 20000 LEGACY surgical system (n = 9) or to 2 minutes of pulsed US at 50% power, 50% of the time at 20 pps using the Alcon INFINITI Vision System (n = 5), and irrigated with 250 mL of either NGOIS or BSS PLUS. A control group of paired corneas did not undergo phacoemulsification or irrigation-aspiration (n = 5). Corneas were divided and fixed for mucin staining or transmission electron microscopy. Mucin layer thickness was measured on the transmission electron microscopy prints. The mucin layer thickness in the continuous phaco group was 0.77 +/- 0.02 microm (mean +/- SE) with NGOIS and 0.51 +/- 0.01 microm with BSS PLUS (t test, P INFINITI Vision System (pulsed US) and the LEGACY surgical system (continuous US).

  19. Evaluation of Yield and Yield Components of Black Cumin (Nigella sativa L. under different Plant Density and Limited Irrigation Condition

    Directory of Open Access Journals (Sweden)

    Sh Rezvan Beidokhti

    2012-10-01

    Full Text Available Research on crop response to deficit irrigation is important to reduce agriculture water use in areas where water is limited resource. Using drought resistant landraces with irrigation scheduling based on phenological stages in semi-arid and arid regions may provide an opportunity to optimize irrigation efficiency and water savings in these regions. In order to evaluate of yield and yield components of black cumin under different plant density and limited irrigation condition an experiment was conducted in Research Farm of Islamic Azad University of Damghan during growing season of 2007-2008. The experimental treatments were arranged in split plots based on a complete randomized block design with three replications. The limited irrigation (based on phenological stages treatments were included: cutting irrigation at blooming (folded flowers, cutting irrigation at flowering stage, cutting irrigation at seed formation and normal weekly irrigation (control were allocated to the main plots and different plant density: 100, 150, 200 and 250 plant per square meter (m2 were allocated to sub plots. The results showed that the effect of limited irrigation, plant density and their interaction on plant height, number of follicle, follicle weight, number of seed, 1000 seed weight, seed yield, biological yield and harvest index Black Cumin. The highest yield and yield components was obtained in normal irrigation (control and 200 plant density and the lowest yield were obtained when irrigation cut at the blooming stage and 250 plant density. There was a significant correlation between seed yield and number (r=0.90, 1000 seed weight (r=0.95 and biological yield (r=0.97. Optimum plant density of black cumin was decreased under limited irrigation treatments. Under normal (control and limited irrigation, optimum plant density was 200 and 150 plant per (m2 respectively.

  20. Sustainable management after irrigation system transfer : experiences in Colombia - the RUT irrigation district

    NARCIS (Netherlands)

    Urrutia Cobo, N.

    2006-01-01

    Colombiais a tropical country located in South America. It has a total area of 114 million ha. In Colombia two irrigation sectors are distinguished: the small-scale irrigation and the large-scale irrigation sector. The small-scale irrigation sector is developed on lands

  1. Irrigation Training Manual. Planning, Design, Operation, and Management of Small-Scale Irrigation Systems [and] Irrigation Reference Manual. A Technical Reference to Be Used with the Peace Corps Irrigation Training Manual T0076 in the Selection, Planning, Design, Operation, and Management of Small-Scale Irrigation Systems.

    Science.gov (United States)

    Salazar, LeRoy; And Others

    This resource for trainers involved in irrigated agriculture training for Peace Corps volunteers consists of two parts: irrigation training manual and irrigation reference manual. The complete course should fully prepare volunteers serving as irrigation, specialists to plan, implement, evaluate and manage small-scale irrigation projects in arid,…

  2. BIOMETRIC PARAMETERS OF FIELD GROWN SESAME INFLUENCED BY ARBUSCULAR MYCORRHIZAL INOCULATION, ROCK PHOSPHATE FERTILIZATION AND IRRIGATION

    Directory of Open Access Journals (Sweden)

    V.S. Harikumar

    2017-08-01

    Full Text Available The aim of the study was to assess the effect of inoculation with arbuscular mycorrhizal fungi (AMF and rock phosphate (RP fertilization on biometric parameters and mycorrhizal colonization of field grown sesame under rainfed and irrigated conditions. Inoculation of AMF Funneliformis dimorphicus improved the biometric parameters of the crop such as leaf area (LA, leaf area index (LAI, specific leaf weight (SLW, net assimilation rate (NAR, oil index (OI as well as mycorrhizal colonization (%F in roots. Mycorrhizal inoculation however, did not give any positive response on harvest index (HI. LA, LAI and OI and %F showed a general increment in treatments of no added P (P0, while the other parameters such as SLW and NAR were improved by the application of RP at half the recommended dose (P50. HI did not respond to RP fertilization. Most of the parameters (LA, LAI, NAR, %F showed higher values under rainfed condition than irrigated condition whereas, SLW, HI and OI improved significantly under irrigated condition. Results indicated that the inoculation of AMF to field grown sesame can compensate for 50% of the recommended P fertilizer under a need based irrigation schedule, without affecting the biometric parameters.

  3. EFFICACY OF DIFFERENT ENDODONTIC IRRIGATION PROTOCOLS IN CALCIUM HYDROXIDE REMOVAL

    Directory of Open Access Journals (Sweden)

    Elka N. Radeva

    2016-10-01

    Full Text Available Introduction: Calcium hydroxide is widely used in the field of endodontics as a temporary root canal filling. This medicament significantly increases pH and optimizes the treatment outcome. Its total removal before final obturation is very important. Otherwise it could affect the hermetic filling and respectively the endodontic success. Aim: To evaluate the most effective irrigation protocol of calcium hydroxide removal from root canals. Materials and methods: In this study 36 single root canal teeth were observed. They were randomly divided into three groups (n=10 each group according to the technique applied for calcium hydroxide removal - manual irrigation, irrigation and Revo-S rotary instrumentation; and passive ultrasonic irrigation, and a control group (n=6 – irrigation with distilled water only. After calcium hydroxide removals following the procedures above, teeth were separated longitudinally in a buccal-lingual direction and remnants of medicaments were observed in the apical, middle and coronal part of each tooth. Then all of the specimens were observed using scanning electron microscopy and evaluated by a specified scale. The results have undergone statistical analysis. Results: In the case of calcium hydroxide in the apex and in the middle with highest average is Revo-S, followed by Ultrasonic and irrigation. In the coronal part the highest average belongs to Revo-S, irrigation and Ultrasonic. In all groups the highest average is represented by control group. Conclusion: There is not a universal technique for removal of intracanal medicaments and applying more than one protocol is required.

  4. Use of Peristeen® transanal colonic irrigation for bowel management in children: a single-center experience.

    Science.gov (United States)

    Pacilli, Maurizio; Pallot, David; Andrews, Afiya; Downer, Angela; Dale, Louiza; Willetts, Ian

    2014-02-01

    Transanal colonic irrigation has been shown to be effective in bowel management program in adults. However, there exist limited data in children. We appraised the effectiveness of this technique in a series of children with incontinence or constipation and overflow soiling. Following ethical approval, a review of children with incontinence or constipation on a bowel management program with Peristeen® transanal colonic irrigation treated between 2007 and 2012 was performed. Irrigations were performed with a volume of 10-20 ml/kg of water with schedules depending on patient response. Data are reported as median (range). Twenty-three patients were reviewed. Median age at commencement of irrigations was 7 (2-15) years. Median follow-up is 2 (0.7-3.4) years. Diagnoses include the following: spina bifida (n=11), anorectal anomaly (n=6), Hirschsprung's (n=1), and other complex anomalies (n=5). Sixteen (70%) patients had associated anomalies. Twelve (52%) had constipation and overflow soiling, and 11 (48%) had fecal incontinence. Twenty (87%) had associated urinary wetting. Sixteen (70%) children used alternate-day irrigations, 4 (17%) daily irrigations, and 3 (13%) every third-day irrigations. Nine (39%) patients were taking oral laxatives. Sixteen (70%) reported to be clean and 3 (13%) reported a significant improvement, although were having occasional soiling. Four patients (17%) did not tolerate the irrigations and underwent subsequent colostomy formation for intractable soiling. In our experience, Peristeen® transanal colonic irrigation is an effective method of managing patients with focal soiling in childhood. Majority (83%) of children achieve social fecal continence or a significant improvement with occasional soiling. This was accompanied by high parental satisfaction. Peristeen® transanal colonic irrigation is a valid alternative to invasive surgical procedures and should be considered the first line of treatment for bowel management in children with soiling

  5. Assessment of irrigation performance: contribution to improve water management in a small catchment in the Brazilian savannas

    Science.gov (United States)

    Rodrigues, Lineu; Marioti, Juliana; Steenhuis, Tammo; Wallender, Wesley

    2010-05-01

    systems, one microirrigation system and three center pivots schemes. Field evaluations used the method advocated by Keller and Bliesner and conducted during farmer scheduled irrigation. Soil samples were taken before irrigations to investigate adequacy of water applied. Since the irrigation water management and the uniformity of water distribution are the two major factors used to define the quality of irrigation, the following criteria for uniformity was used: i) Localized irrigations (distribution uniformity - UD) - excellent (90% management criteria, in agricultural basins, once irrigation water becomes limiting and reduces basin water productivity.

  6. SPANR planning and scheduling

    Science.gov (United States)

    Freund, Richard F.; Braun, Tracy D.; Kussow, Matthew; Godfrey, Michael; Koyama, Terry

    2001-07-01

    SPANR (Schedule, Plan, Assess Networked Resources) is (i) a pre-run, off-line planning and (ii) a runtime, just-in-time scheduling mechanism. It is designed to support primarily commercial applications in that it optimizes throughput rather than individual jobs (unless they have highest priority). Thus it is a tool for a commercial production manager to maximize total work. First the SPANR Planner is presented showing the ability to do predictive 'what-if' planning. It can answer such questions as, (i) what is the overall effect of acquiring new hardware or (ii) what would be the effect of a different scheduler. The ability of the SPANR Planner to formulate in advance tree-trimming strategies is useful in several commercial applications, such as electronic design or pharmaceutical simulations. The SPANR Planner is demonstrated using a variety of benchmarks. The SPANR Runtime Scheduler (RS) is briefly presented. The SPANR RS can provide benefit for several commercial applications, such as airframe design and financial applications. Finally a design is shown whereby SPANR can provide scheduling advice to most resource management systems.

  7. Assessing the adaptive capacity of maize hybrids to climate change in an irrigated district of Southern Italy

    Science.gov (United States)

    Monaco, Eugenia; Bonfante, Antonello; De Mascellis, Roberto; Alfieri, Silvia Maria; Menenti, Massimo; De Lorenzi, Francesca

    2013-04-01

    Climate change will cause significant changes in water distribution and availability; as a consequence the water resources in some areas (like Mediterranean regions) will be limiting factors to the cultivation of some species, included cereals. So the perspective of climate change requires an analysis of the adaptation possibilities of food and fiber species currently cultivated. A powerful tool for adaptation is the relevant intra-specific biodiversity of crops. The knowledge, for different crop cultivars, of the responses to different environmental conditions (e.g. yield response functions to water regime) can be a tool to identify adaptation options to future climate. Moreover, simulation models of water flow in the soil-plant-atmosphere system can be coupled with future climate scenarios to predict the soil water regime also accounting for different irrigation scheduling options. In this work the adaptive capacity of maize hybrids (Zea mays L.) was evaluated in an irrigated district of Southern Italy (the "Destra Sele" plain, an area of about 18.000 ha), where maize is extensively grown for water buffalo feeding. Horticultural crops (tomato, fennel, artichoke) are grown, as well. The methodology applied is based on two complementary elements: - a database on climatic requirements of 30 maize hybrids: the yield response functions to water availability were determined from experimental data derived both from scientific literature and from field trials carried out by ISAFOM-CNR. These functions were applied to describe the behaviour of the hybrids with respect to the relative evapotranspiration deficit; - the simulation performed by the agro-hydrological model SWAP (soil-water-plant and atmosphere), to determine the future soil water regime at landscape scale. Two climate scenarios were studied: "past" (1961-1990) and "future" (2021-2050). Future climate scenarios were generated within the Italian National Project AGROSCENARI. Climate scenarios at low spatial

  8. The Temporal Variation of Leaf Water Potential in Pistachio under Irrigated and Non-Irrigated Conditions

    Directory of Open Access Journals (Sweden)

    Yusuf AYDIN

    2014-09-01

    Full Text Available The present study was carried out in the experimental field of Pistachio Research Institute on pistachio trees which has uzun variety that was 30 years old. The aim of this research was to determine the Leaf Water Potential (LWP of Pistacia vera L. under irrigated and non-irrigated conditions. In the study, the leaf water potential of pistachio was investigated under fully irrigated and non irrigated conditions. The leaf water potential values were measured one day before and after irrigation by using pressure chamber technique at the beginning, mid and end of irrigation season. According to the results obtained from measurements, the LWP value at the beginning of the irrigation season was -3.7 MPa at noon time due to relatively high temperature for both treatments. At the time of pre-dawn and sunset, this value increased and reached to - 1.6 MPa due to relatively low temperature. In general, the LWP values during the mid of irrigation season, in the irrigated treatments, reached to almost -2.5 MPa in the non-irrigated treatment and the value was measured as -3.68 MPa.

  9. Effect of low-cost irrigation methods on microbial contamination of lettuce irrigated with untreated wastewater

    DEFF Research Database (Denmark)

    Keraita, Bernard; Konradsen, Flemming; Drechsel, P.

    2007-01-01

    OBJECTIVE: To assess the effectiveness of simple irrigation methods such as drip irrigation kits, furrow irrigation and use of watering cans in reducing contamination of lettuce irrigated with polluted water in urban farming in Ghana. METHODS: Trials on drip kits, furrow irrigation and watering...... cans were conducted with urban vegetable farmers. Trials were arranged in a completely randomised block design with each plot having all three irrigation methods tested. This was conducted in both dry and wet seasons. Three hundred and ninety-six lettuce, 72 soil, 15 poultry manure and 32 water samples...... were analysed for thermotolerant coliforms and helminth eggs. RESULTS: Lettuce irrigated with drip kits had the lowest levels of contamination, with, on average, 4 log units per 100 g, fewer thermotolerant coliforms than that irrigated with watering cans. However, drip kits often got clogged, required...

  10. Apical extrusion of debris and irrigant using hand and rotary systems: A comparative study

    Science.gov (United States)

    Ghivari, Sheetal B; Kubasad, Girish C; Chandak, Manoj G; Akarte, NR

    2011-01-01

    Aim: To evaluate and compare the amount of debris and irrigant extruded quantitatively by using two hand and rotary nickel–titanium (Ni–Ti) instrumentation techniques. Materials and Methods: Eighty freshly extracted mandibular premolars having similar canal length and curvature were selected and mounted in a debris collection apparatus. After each instrument change, 1 ml of distilled water was used as an irrigant and the amount of irrigant extruded was measured using the Meyers and Montgomery method. After drying, the debris was weighed using an electronic microbalance to determine its weight. Statistical analysis used: The data was analyzed statistically to determine the mean difference between the groups. The mean weight of the dry debris and irrigant within the group and between the groups was calculated by the one-way ANOVA and multiple comparison (Dunnet D) test. Results: The step-back technique extruded a greater quantity of debris and irrigant in comparison to other hand and rotary Ni–Ti systems. Conclusions: All instrumentation techniques extrude debris and irrigant, it is prudent on the part of the clinician to select the instrumentation technique that extrudes the least amount of debris and irrigant, to prevent a flare-up phenomena. PMID:21814364

  11. Efficacy of passive ultrasonic irrigation with natural irrigants (Morinda citrifolia juice, Aloe Vera and Propolis) in comparison with 1% sodium hypochlorite for removal of E. faecalis biofilm: an in vitro study.

    Science.gov (United States)

    Bhardwaj, Anuj; Velmurugan, Natanasabapathy; Ballal, Suma

    2013-01-01

    Present study evaluated the efficacy of natural derivative irrigants, Morinda citrifolia juice (MCJ), Aloe Vera and Propolis in comparison to 1% sodium hypochlorite with passive ultrasonic irrigation for removal of the intraradicular E. faecalis biofilms in extracted single rooted human permanent teeth. Biofilms of E. faecalis were grown on the prepared root canal walls of 60 standardized root halves which were longitudinally sectioned. These root halves were re-approximated and the samples were divided into five groups of twelve each. The groups were, Group A (1% NaOCl), Group B (MCJ), Group C (Aloe vera), Group D (Propolis) and Group E (Saline). These groups were treated with passive ultrasonic irrigation (PUI) along with the respective irrigants. The root halves were processed for scanning electron microscopy. Three images (X2.5), coronal, middle and apical, were taken for the twelve root halves in each of the five groups. The images were randomized and biofilm coverage assessed independently by three calibrated examiners, using a four-point scoring system. 1% NaOCl with passive ultrasonic irrigation (PUI) was effective in completely removing E. faecalis biofilm and was superior to the natural irrigants like MCJ, Aloe vera and Propolis tested in this study. 1% NaOCl used along with passive ultrasonic irrigation was effective in completely removing E. faecalis biofilm when compared to natural irrigants (MCJ, Aloe Vera and Propolis).

  12. IRRIGATION USING SOLAR PUMP

    OpenAIRE

    Prof. Nitin P.Choudhary*1 & Ms. Komal Singne2

    2017-01-01

    In this report the described design of a PV and soil moisture sensor based automated irrigation system is introduced. This project aims to provide a human friendly, economical and automated water pumping system which eliminates the problems of over irrigation and helps in irrigation water optimization and manage it in accordance with the availability of water. Our project not only tries to modernize the irrigation practices and ensure the optimum yield by carefully fulfilling the requirements...

  13. Contribution to the improvement of irrigation management practices through water - deficit irrigation

    International Nuclear Information System (INIS)

    Bazza, M.

    1995-01-01

    The study aimed at identifying irrigation management practices which could result in water savings through -water deficit irrigation. Two field experiments, one on wheat and the other on sugar beet, were conducted and consisted of refraining from supplying water during specific stages of the cycle so as to identy the period(s) during which water deficit would have a limited effect on crop production. In the case of wheat, high water deficit occurred during the early and during these stages was the most beneficial for the crop. However, one water application during the tillering stage allowed the yield to be lower only to that of the treatement with three irrigations. Irrigation during the stage of grain filling caused the kernel weight to be as high as under three irrigations. The lowest value corresponded to the treatement with one irrigation during grain filling and that under rainfed conditions. For sugar beet, when water stress was was applied early in the crop cycle, its effect could be almost entirely recovered with adequate watering during the rest of the growing season. On the opposite, good watering early in cycle, followed by a stress, resulted in the second lowest yield. Water deficit during the maturity stage had also a limited effect on yield. The most crucial periods for adequate watering were which correspond to late filiar development and root growth which coincided with the highest water requirements period. For the same amount of water savings through deficit irrigation, it was better to partition the stress throughout the cycle than during the critical stages of the crop. However, at the national level, it would have been more important to practice deficit irrigation and the irrigated area. For both crops, high yields as high as water - use efficiency values could have been obtained. 8 tabs; 5 refs ( Author )

  14. Political Economy and Irrigation Technology Adoption Implications of Water Pricing under Asymmetric Information

    OpenAIRE

    Dridi, Chokri; Khanna, Madhu

    2005-01-01

    We analyze the design of water pricing rules emerging from farmers' lobbying and their implications for the size of the lobby, water use, profits and social welfare. The lobbying groups are the adopters of modern irrigation technology and the non-adopters. The pricing rules are designed to meet budget balance of water provision; we considered (i) a two-part tariff composed of a mandatory per-acre fee plus a volumetric charge and (ii) a nonlinear pricing schedule. Our results show that under e...

  15. Automation of irrigation systems to control irrigation applications and crop water use efficiency

    Science.gov (United States)

    Agricultural irrigation management to slow water withdrawals from non-replenishing quality water resources is a global endeavor and vital to sustaining irrigated agriculture and dependent rural economies. Research in site-specific irrigation management has shown that water use efficiency, and crop p...

  16. Ghana - Agriculture - Irrigation

    Data.gov (United States)

    Millennium Challenge Corporation — The Millennium Development Authority (MiDA) financed the construction of a new irrigation scheme in Kpong and the renovation of two irrigation schemes in Botanga and...

  17. Applications of Satellite Data to Support Improvements in Irrigation and Groundwater Management in California

    Science.gov (United States)

    Melton, F. S.; Huntington, J. L.; Johnson, L.; Guzman, A.; Morton, C.; Zaragoza, I.; Dexter, J.; Rosevelt, C.; Michaelis, A.; Nemani, R. R.; Cahn, M.; Temesgen, B.; Trezza, R.; Frame, K.; Eching, S.; Grimm, R.; Hall, M.

    2017-12-01

    In agricultural regions around the world, threats to water supplies from drought and groundwater depletion are driving increased demand for tools to advance agricultural water use efficiency and support sustainable groundwater management. Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water resource managers with information that can be used to both optimize ag water use and improve estimates of groundwater withdrawals for irrigation. We describe the development of two remote sensing-based tools for ET mapping in California, including important lessons in terms of system design, partnership development, and transition to operations. For irrigation management, the integration of satellite data and surface sensor networks to provide timely delivery of information on crop water requirements can make irrigation scheduling more practical, convenient, and accurate. Developed through a partnership between NASA and the CA Department of Water Resources, the Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development and crop water requirements at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based interface and web data services. SIMS also provides an API that facilitates integration with other irrigation decision support tools, such as CropManage and IrriQuest. Field trials using these integrated tools have shown that they can be used to sustain yields while improving water use efficiency and nutrient management. For sustainable groundwater management, the combination of satellite-derived estimates of ET and data on surface water deliveries for irrigation can increase the accuracy of estimates of groundwater pumping. We are developing an OpenET platform to facilitate access to ET data from multiple models and accelerate operational

  18. Traditional Irrigation Management in Betmera-Hiwane, Ethiopia: The Main Peculiarities for the Persistence of Irrigation Practices

    Institute of Scientific and Technical Information of China (English)

    Solomon Habtu; Kitamura Yoshinobu

    2006-01-01

    Traditional irrigation, as part of the ancient agricultural practices in northern Ethiopia (Tigray), has persisted for long time since 500 B.C.,while many newly introduced irrigation projects have usually failed there. The main objective of this study is thus to investigate the peculiarities pertinent to irrigation management and those having contributed for the persistence of traditional irrigation practices for a long period of time. The experience gained from such areas can definitely help make irrigation management system of new irrigation schemes sustainable. Betmera-Hiwane, one of the ancient traditional irrigation areas in Tigray region, was selected for the field study. Direct observations through field visits accompanied by interviews to farmers, local officials, local knowledgeable individuals and higher officials were made. After analyzing the collected primary and secondary information, the main peculiarities that contributed to the persistence of traditional irrigation areas were identified, and they are: the presence of communally constructed local rules, locally designed hydraulic control structures, ownership feeling of the irrigators and accountability of water distributors to the irrigation management, the culture for mobilizing communal resources and the culture of self-initiating local water management strategies.

  19. Modernized Irrigation Technologies in West Africa

    Directory of Open Access Journals (Sweden)

    Hakan Büyükcangaz

    2017-12-01

    Full Text Available Crop production in West Africa is mostly dependent upon rainfed agriculture. Irrigation is a vital need due to uneven distribution of rainfall and seasonality of water resources. However, management and sustainability of irrigation are under risk due to notably weak database, excessive cost, unappropriate soil or land use, environmental problems and extreme pessimism in some quarters since rainfed agriculture is seen as potentially able to support the present population. This paper focuses on modernized irrigation technologies and systems that utilize less water. Information about irrigation systems in Ghana and Liberia were gathered through: 1 Irrigation development authorities in both countries, by reviewing past literatures, online publications, reports and files about irrigation in West Africa, specifically Ghana and Liberia; 2 International Food Policy Research Institute (IFPRI; 3 Collation of information, reports and data from Ghana Irrigation Development Authority (GIDA and 4 International Water Management Institute (IWMI. The result shows that both countries have higher irrigation potential. However, the areas developed for irrigation is still a small portion as compare to the total land available for irrigation. On the other hand, as seen in the result, Liberia as compare to Ghana has even low level of irrigation development.

  20. Irrigation in endodontic treatment.

    Science.gov (United States)

    Basrani, Bettina

    2011-01-01

    The primary endodontic treatment goal is to optimize root canal disinfection and to prevent reinfection. Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal system. In this review of the literature, various irrigants and the interactions between irrigants are discussed and new delivery systems are introduced.

  1. The effect of irrigation time and type of irrigation fluid on cartilage surface friction.

    Science.gov (United States)

    Stärke, F; Awiszus, F; Lohmann, C H; Stärke, C

    2018-01-01

    It is known that fluid irrigation used during arthroscopic procedures causes a wash-out of lubricating substances from the articular cartilage surface and leads to increased friction. It was the goal of this study to investigate whether this effect depends on the time of irrigation and type of fluid used. Rabbit hind legs were used for the tests. The knees were dissected and the friction coefficient of the femoral cartilage measured against glass in a boundary lubrication state. To determine the influence of irrigation time and fluid, groups of 12 knees received either no irrigation (control), 15, 60 or 120min of irrigation with lactated Ringer's solution or 60min of irrigation with normal saline or a sorbitol/mannitol solution. The time of irrigation had a significant effect on the static and kinetic coefficient of friction (CoF), as had the type of fluid. Longer irrigation time with Ringer's solution was associated with increased friction coefficients (relative increase of the kinetic CoF compared to the control after 15, 60 and 120min: 16%, 76% and 88% respectively). The sorbitol/mannitol solution affected the static and kinetic CoF significantly less than either Ringer's or normal saline. The washout of lubricating glycoproteins from the cartilage surface and the associated increase of friction can be effectively influenced by controlling the time of irrigation and type of fluid used. The time of exposure to the irrigation fluid should be as short as possible and monosaccharide solutions might offer a benefit compared to salt solutions in terms of the resultant friction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.

    Science.gov (United States)

    Abrahão, Raphael; Carvalho, Monica; Causapé, Jesús

    2017-02-01

    Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions. Due to concerns about climate change and water availability, the methods selected for evaluation of environmental impacts were IPCC 2013 GWP (carbon footprint) and water scarcity indicator (water footprint). The area studied, a 7.38-km 2 basin, was monitored for 12 years, including the period before, during, and after the implementation of irrigation. The functional unit, to which all material and energy flows were associated with, was the cultivation of 1 ha, throughout 1 year. The overall carbon footprint for irrigated corn was higher, but when considering the higher productivity achieved with irrigation, the emissions per kilogram of corn decrease and finally favor this irrigated crop. When considering the water footprint, the volumes of irrigation water applied were so high that productivity could not compensate for the negative impacts associated with water use in the case of corn. Nevertheless, consideration of productivities and gross incomes brings the results closer. Fertilizer use (carbon footprint) and irrigation water (water footprint) were the main contributors to the negative impacts detected.

  3. Making the user visible: analysing irrigation practices and farmers’ logic to explain actual drip irrigation performance

    NARCIS (Netherlands)

    Benouniche, M.; Kuper, M.; Hammani, A.; Boesveld, H.

    2014-01-01

    The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the field is often quite different from that obtained in experimental stations. We developed an approach to explain the actual irrigation performance of drip irrigation systems by linking measured

  4. On the irrigation requirements of cottonwood (Populus fremontii and Populus deltoides var. wislizenii) and willow (Salix gooddingii) grown in a desert environment

    Science.gov (United States)

    Hartwell, S.; Morino, K.; Nagler, P.L.; Glenn, E.P.

    2010-01-01

    Native tree plots have been established in river irrigation districts in the western U.S. to provide habitat for threatened and endangered birds. Information is needed on the effective irrigation requirements of the target species. Cottonwood (Populus spp.) and willow (Salix gooddingii) trees were grown for seven years in an outdoor plot in a desert environment in Tucson, Arizona. Plants were allowed to achieve a nearly complete canopy cover over the first four years, then were subjected to three daily summer irrigation schedules of 6.20??mm??d-1; 8.26??mm??d-1 and 15.7??mm??d-1. The lowest irrigation rate was sufficient to maintain growth and high leaf area index for cottonwoods over three years, while willows suffered considerable die-back on this rate in years six and seven. These irrigation rates were applied April 15-September 15, but only 0.88??mm??d-1 was applied during the dormant period of the year. Expressed as a fraction of reference crop evapotranspiration (ETo), recommended annual water applications plus precipitation (and including some deep drainage) were 0.83 ETo for cottonwood and 1.01 ETo for willow. Current practices tend to over-irrigate restoration plots, and this study can provide guidelines for more efficient water use. ?? 2010 Elsevier Ltd.

  5. How Patients Experience Antral Irrigation

    Directory of Open Access Journals (Sweden)

    Karin Blomgren

    2015-01-01

    Full Text Available Background Antral irrigation earlier had an important role in the diagnosis and treatment of rhinosinusitis. Nowadays, it is often considered too unpleasant. However, the experience of patients of this procedure has been very seldom evaluated. Nor has the effect on pain in rhinosinusitis been evaluated. The aim of this study was to evaluate patients’ experience of discomfort and pain during antral irrigation. We also assessed facial pain caused by rhinosinusitis before the procedure and pain soon after the procedure. Methods Doctors and 121 patients completed their questionnaires independently after antral irrigation in a university clinic, in a private hospital, and at a communal health center. Results Patients experienced mild pain during antral irrigation (mean and median visual analog scale score: <3. Their experience of pain during antral irrigation was closely comparable to pain during dental calculus scaling. Facial pain assessed before antral irrigation decreased quickly after the procedure. Conclusions Antral irrigation was well tolerated as an outpatient procedure. The procedure seems to relieve facial pain caused by the disease quickly. The role of antral irrigation in the treatment of acute rhinosinusitis will need further investigation.

  6. Modernisation Strategy for National Irrigation Systems in the Philippines: Balanac and Sta. Maria River Irrigation Systems

    NARCIS (Netherlands)

    Delos Reyes, M.L.F.

    2017-01-01

    This book examines the nature and impact of irrigation system rehabilitation on increasing the actual area irrigated by the publicly funded canal irrigation systems of the Philippines. It proposes a system diagnosis approach for the development of a more appropriate and climate-smart irrigation

  7. Attitudes, beliefs, and practices regarding electronic nicotine delivery systems in patients scheduled for elective surgery.

    Science.gov (United States)

    Kadimpati, Sandeep; Nolan, Margaret; Warner, David O

    2015-01-01

    Smokers are at increased risk of postoperative complications. Electronic nicotine delivery systems (ENDS; or electronic cigarettes) could be a useful tool to reduce harm in the perioperative period. This pilot study examined the attitudes, beliefs, and practices of smokers scheduled for elective surgery regarding ENDS. This was a cross-sectional survey of current cigarette smokers who were evaluated in a preoperative clinic before elective surgery at Mayo Clinic. Measures included demographic characteristics, smoking history, 2 indices assessing the perception of how smoking affected health risks, ENDS use history, and 3 indices assessing interest in, perceived benefits of, and barriers to using ENDS in the perioperative period. Of the 112 smokers who completed the survey, 62 (55%) had tried ENDS and 24 (21%) reported current use. The most commonly stated reason for using ENDS was to quit smoking. Approximately 2 in 3 participants would be willing to use ENDS to help them reduce or eliminate perioperative cigarette use, and similar proportions perceived health benefits of doing so. Of the factors studied, only attempted to quit within the last year was significantly associated with increased interest in the perioperative use of ENDS (P=.03). Compared with participants who had tried ENDS (n=62), those who had never tried ENDS (n=50) had a significantly increased interest in the perioperative use of ENDS. A substantial proportion of patients scheduled for elective surgery had tried ENDS and would consider using ENDS to reduce perioperative use of cigarettes. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  8. Effect of regulated deficit irrigation and crop load on the antioxidant compounds of peaches.

    Science.gov (United States)

    Buendía, Begoña; Allende, Ana; Nicolás, Emilio; Alarcón, Juan J; Gil, Maria I

    2008-05-28

    The use of regulated deficit irrigation (RDI) strategies is becoming a common practice in areas with low water availability. Little information is available about the effects of RDI on the antioxidant content of fruits. In this study, the influence of RDI on the content of vitamin C, phenolic compounds and carotenoids was investigated. Two irrigation strategies, fully irrigated (FI) and RDI, were compared at two levels of thinning, commercial and half of the commercial crop load. RDI strategies affected the content of vitamin C, phenolics and carotenoids of Flordastar peaches. RDI caused fruit peel stress lowering the content of vitamin C and carotenoids, while increasing the phenolic content, mainly anthocyanins and procyanidins. Fruit weight was the only quality index influenced by the crop load as it increased in FI fruits at low crop load. In general, fruits from commercial crop load had slightly higher content of antioxidants to fruits from low crop load, although these influences were only observed in the peel. Additionally, the influence of irrigation controlled by two sensors related to plant water level, maximum daily trunk shrinkage (MDS) and sap flow (SF) on the antioxidant constituents of peaches was evaluated. The response of the fruits to SF sensor was similar to that observed for RDI strategy. According to the tested water sensors, SF did not act as a good plant-based water indicator for use in irrigation scheduling, as it caused an increase in the content of phenolics, similar to that observed for fruits subjected to RDI. Therefore, selection of RDI strategies and plant water indicators should be taken into account as they affect the content of antioxidants of peaches.

  9. Effect of long-term irrigation patterns on phosphorus forms and distribution in the brown soil zone.

    Directory of Open Access Journals (Sweden)

    Chang Liu

    Full Text Available Continuous application of P fertilizers under different irrigation patterns can change soil phosphorus (P chemical behavior and increase soil P levels that are of environmental concern. To assess the effect of long-term different irrigation patterns on soil P fractions and availability, this study examined sequential changes in soil organic P and inorganic P from furrow irrigation (FI, surface drip irrigation (SUR, and subsurface drip irrigation (SDI in the brown soil zone (0-60 cm during 1998 to 2011. Analyses of soil P behavior showed that the levels of total P are frequently high on top soil layers. The total P (TP contents of the entire soil profiles under three irrigation treatments were 830.2-3180.1 mg/kg. The contents of available P (AP were 72.6-319.3 mg P/kg soil through soil profiles. The greatest TP and AP contents were obtained within the upper soil layers in FI. Results of Hedley's P fractionation indicate that HCl-P is a dominant form and the proportion to TP ranges from 29% to 43% in all three methods. The contents of various fractions of P were positively correlated with the levels of total carbon (TC, total inorganic carbon (TIC, and calcium (Ca, whereas the P fractions had negative correlation with pH in all soil samples. Regression models proved that NaHCO3-Po was an important factor in determining the amount of AP in FI. H2O-Po, NaHCO3-Po, and NaOH-Pi were related to available P values in SUR. NaHCO3-Po and NaOH-Po played important roles in SDI. The tomato yield under SUR was higher than SDI and FI. The difference of P availability was also controlled by the physicochemical soil properties under different irrigation schedule. SUR was a reasonable irrigation pattern to improve the utilization efficiency of water and fertilizer.

  10. Incentives and technologies for improving irrigation water use efficiency

    Science.gov (United States)

    Bruggeman, Adriana; Djuma, Hakan; Giannakis, Elias; Eliades, Marinos

    2014-05-01

    from the government irrigation network, with an additional fixed fee of 66.10 euro per ha per season. This is a substantial increase from the 0.17 euro per3 and 17.10 euro per ha fixed fee. The price for individual abstractions has been set at 0.11 euro per m^3. However, these new prices have not yet been approved by the Parliament. Agriculture in Cyprus is highly fragmented. The average farm size is 3.5 ha, while each farm holds on average 5 parcels (agricultural census of 2003). Stakeholder interviews indicated that, in general, small farmers in Cyprus have not considered investments in advanced irrigation scheduling technologies to counter balance the loom of higher water prices. However, the picture is different for large producers. A large citrus producer was interested in testing the ENORASIS technology. The first season of measurements indicated that water can be used more efficiently and that the ENORASIS system provides an important tool for reducing on-farm irrigation water use.

  11. Irrigation water sources and irrigation application methods used by U.S. plant nursery producers

    Science.gov (United States)

    Paudel, Krishna P.; Pandit, Mahesh; Hinson, Roger

    2016-02-01

    We examine irrigation water sources and irrigation methods used by U.S. nursery plant producers using nested multinomial fractional regression models. We use data collected from the National Nursery Survey (2009) to identify effects of different firm and sales characteristics on the fraction of water sources and irrigation methods used. We find that regions, sales of plants types, farm income, and farm age have significant roles in what water source is used. Given the fraction of alternative water sources used, results indicated that use of computer, annual sales, region, and the number of IPM practices adopted play an important role in the choice of irrigation method. Based on the findings from this study, government can provide subsidies to nursery producers in water deficit regions to adopt drip irrigation method or use recycled water or combination of both. Additionally, encouraging farmers to adopt IPM may enhance the use of drip irrigation and recycled water in nursery plant production.

  12. Container volume and subirrigation schedule influence Quercus variabilis seedling growth and nutrient status in the nursery and field

    Science.gov (United States)

    Qiaoyu Sun; R. Kasten Dumroese; Yong Liu

    2018-01-01

    Container volume and irrigation management affect seedling growth in the nursery and field. We evaluated the effects of container volumes (D40, 656 ml; D60, 983 ml) and subirrigation schedules (85%, 75%, 65%, and 55% of 100% total substrate moisture content, TSMC) on seedling growth in a greenhouse and outplanting performance of Chinese cork oak (Quercus variabilis...

  13. Scintigraphic assessment of colostomy irrigation.

    Science.gov (United States)

    Christensen, P.; Olsen, N.; Krogh, K.; Laurberg, S.

    2002-09-01

    OBJECTIVE: This study aims to evaluate colonic transport following colostomy irrigation with a new scintigraphic technique. MATERIALS AND METHODS: To label the bowel contents 19 patients (11 uncomplicated colostomy irrigation, 8 complicated colostomy irrigation) took 111In-labelled polystyrene pellets one and two days before investigation. 99mTc-DTPA was mixed with the irrigation fluid to assess its extent within the bowel. Scintigraphy was performed before and after a standardized washout procedure. The colon was divided into three segments 1: the caecum andascending colon; 2: the transverse colon; 3: the descending and sigmoid colon. Assuming ordered evacuation of the colon, the contribution of each colonic segment to the total evacuation was expressed as a percentage of the original segmental counts. These were added to reach a total defaecation score (range: 0-300). RESULTS: In uncomplicated colostomy irrigation, the median defaecation score was 235 (range: 145-289) corresponding to complete evacuation of the descending and transverse colon and 35% evacuation of the caecum/ascending colon. In complicated colostomy irrigation it was possible to distinguish specific emptying patterns. The retained irrigation fluid reached the caecum in all but one patient. CONCLUSION: Scintigraphy can be used to evaluate colonic emptying following colostomy irrigation.

  14. Modeling irrigation behavior in groundwater systems

    Science.gov (United States)

    Foster, Timothy; Brozović, Nicholas; Butler, Adrian P.

    2014-08-01

    Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas High Plains region of the United States we predict optimal irrigation strategies under variable levels of groundwater supply, and assess the limits of existing models for predicting land and groundwater use decisions by farmers. Our results show that irrigation behavior exhibits complex nonlinear responses to changes in groundwater availability. Declining well yields induce large reductions in the optimal size of irrigated area and irrigation use as constraints on instantaneous application rates limit the ability to maintain sufficient soil moisture to avoid negative impacts on crop yield. We demonstrate that this important behavioral response to limited groundwater availability is not captured by existing modeling approaches, which therefore may be unreliable predictors of irrigation demand, agricultural profitability, and resilience to climate change and aquifer depletion.

  15. Assessment of Irrigation Water Quality and Suitability for Irrigation in ...

    African Journals Online (AJOL)

    A number of factors like geology, soil, effluents, sewage disposal and other environmental conditions in which the water stays or moves and interacts are among the factors that affect the quality of irrigation water. This study was conducted to determine the quality and suitability of different water sources for irrigation purpose ...

  16. Effect of irrigation on heavy metals content of wastewater irrigated ...

    African Journals Online (AJOL)

    There is an urgent need to educate farmers on the dangers of the presence of heavy metals in soils as well as the quality of irrigation water especially if it comes from tanning industries for increased crop production. Accordingly, soil and irrigation wastewater study was conducted to assess the concentrations of heavy ...

  17. Effects of different on-farm management on yield and water use efficiency of Potato crop cultivated in semiarid environments under subsurface drip irrigation

    Science.gov (United States)

    Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid

    2016-04-01

    In Tunisia the amount of water for irrigated agriculture is higher than about 80% of the total resource.The increasing population and the rising food demand, associated to the negative effects of climate change,make it crucial to adopt strategies aiming to improve water use efficiency (WUE). Moreover, the absence of an effective public policy for water management amplifies the imbalance between water supply and its demand. Despite improved irrigation technologies can enhance the efficiency of water distribution systems, to achieve environmental goals it is also necessaryto identify on-farm management strategies accounting for actual crop water requirement. The main objective of the paper was to assess the effects of different on-farm managementstrategies (irrigation scheduling and planting date) on yield and water use efficiency of Potato crop (Solanumtuberosum L.) irrigated with a subsurface drip system, under the semi-arid climate of central Tunisia. Experiments were carried out during three growing seasons (2012, 2014 and 2015) at the High Agronomic Institute of ChottMariem in Sousse, by considering different planting dates and irrigation depths, the latter scheduled according to the climate observed during the season. All the considered treatments received the same pesticide and fertilizer management. Experiments evidenced that the climatic variability characterizing the examined seasons (photoperiod, solar radiation and average temperature) affects considerably the crop phenological stages, and the late sowing shortens the crop cycle.It has also been demonstrated that Leaf Area Index (LAI) and crop yield resulted relatively higher for those treatments receiving larger amounts of seasonal water. Crop yield varied between 16.3 t/ha and 39.1 t/ha, with a trend linearly related to the ratio between the seasonal amount of water supplied (Irrigation, I and Precipitation, P) and the maximum crop evapotranspiration (ETm). The maximum crop yield was in particular

  18. An assessment of colostomy irrigation.

    Science.gov (United States)

    Laucks, S S; Mazier, W P; Milsom, J W; Buffin, S E; Anderson, J M; Warwick, M K; Surrell, J A

    1988-04-01

    One hundred patients with permanent sigmoid colostomies were surveyed to determine their satisfaction and success with the "irrigation" technique of colostomy management. Most patients who irrigate their colostomies achieve continence. Odors and skin irritation are minimized. The irrigation method is economical, time efficient, and allows a reasonably liberal diet. It avoids bulky appliances and is safe. In appropriately selected patients, the irrigation technique is the method of choice for management of an end-sigmoid colostomy.

  19. Irrigation and Autocracy

    DEFF Research Database (Denmark)

    Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

    2017-01-01

    . We argue that the effect has historical origins: irrigation allowed landed elites in arid areas to monopolize water and arable land. This made elites more powerful and better able to oppose democratization. Consistent with this conjecture, we show that irrigation dependence predicts land inequality...

  20. Efficient operation of a multi-purpose reservoir in Chile: Tradeoffs between irrigation and hydropower production

    Science.gov (United States)

    Gonzalez Cabrera, J. M., Sr.; Olivares, M. A.

    2015-12-01

    This study proposes a method to develop efficient operational policies for a reservoir the southern Chile. The main water uses in this system are hydropower and irrigation, with conflicting seasonal demands. The conflict between these two uses is currently managed through a so-called "irrigation agreement" which defines a series of operational conditions on the reservoir by restricting volumes used for power production depending on reservoir storage level. Other than that, the reservoir operation is driven by cost-minimization over the power grid. Recent evidence shows an increasing degree of conflict in this basin, which suggests that the static approach of irrigation agreements, might no longer be appropriate. Moreover, this agreement could be revised in light of decreased water availability. This problem poses a challenge related to the spatial scope of analysis. Thus, irrigation benefits are driven by decisions made within the basin, whereas hydropower benefits depend on the operation of the entire power grid. Exploring the tradeoffs between these two water uses involves modeling both scales. The proposed methodology integrates information from both a grid-wide power operations model and a basin-wide agro-economic model into a decision model for optimal reservoir operation. The first model, a hydrothermal coordination tool, schedules power production by each plant in the grid, and allows capturing technical and economic aspects to the operation of hydropower reservoirs. The agro-economic model incorporates economic features of irrigation in the basin, and allows obtaining irrigation water demand functions. Finally, the results of both models are integrated into a single model for optimal reservoir operation considering the tradeoffs between the two uses. The result of the joint operation of water resources, show a flexible coordination of uses, revealing the opportunity cost of irrigation, which it gives the possibility of negotiating transfers of water to

  1. STUDY ON MICROBIAL COMMUNITIES AND SOIL ORGANIC MATTER IN IRRIGATED AND NON-IRRIGATED VERTISOL FROM BOIANU

    Directory of Open Access Journals (Sweden)

    Sorina Dumitru

    2012-12-01

    Full Text Available Irrigation, when administered correctly, confers the producers the possibility to overcome drought effects and obtain higher yields, supplementing the quality of food for animals or human consumers. In the mean time, soil erosion, pathogens attack and nutrients or pesticides spreading can be prevented by an adequate management of irrigation water. As a consequence, soil microbial community structure, composition and activities, as well as the organic matter quality can be different from those in non-irrigated soil. Research have been carried out in order to assess changes in bacterial and fungal communities and activity in irrigated Vertisol from Boianu, as compared with non-irrigated. The paper presents the results concerning the taxonomical composition of bacterial and fungalmicroflora in the horizons of the two soil profiles, as well as the level of CO2 released by microorganisms. Chromatographic aspects of humus fractions were used to characterize the organic matter in irrigated and nonirrigated soil. Increased moisture and lowered temperature in Ap horizon of irrigated soil increased bacterial counts(18 x106 viable cells x g-1 dry soil and their metabolic activity expressed by carbon dioxide released (46.838mg CO2 x g-1 dry soil comparatively with non- irrigated soil. Fungal microflora was more abundant after 25-50cm under irrigation. Species diversity slightly increased under irrigation in both upper and lower part of soil profile. In irrigated soil, associations of species belonging to bacterial genera Pseudomonas and Bacillus were dominant in surface and white actinomycetes in the depth. Fungal consortia of Penicillium, Aspergillus and Fusarium dominated in both soil profiles.Irrigation induced changes in the quantity and quality of soil organic matter, as well as in the aspect of their migration pattern, as revealed on circular chromatograms.

  2. Estimated Colorado Golf Course Irrigation Water Use, 2005

    Science.gov (United States)

    Ivahnenko, Tamara

    2009-01-01

    Golf course irrigation water-use data were collected as part of the U.S. Geological Survey National Water Use Program's 2005 compilation to provide baseline information, as no golf course irrigation water-use data (separate from crop irrigation) have been reported in previous compilations. A Web-based survey, designed by the U.S. Geological Survey, in cooperation with the Rocky Mountain Golf Course Superintendents Association (RMGCSA), was electronically distributed by the association to the 237 members in Colorado. Forty-three percent of the members returned the survey, and additional source water information was collected by telephone for all but 20 of the 245 association member and non-member Colorado golf courses. For golf courses where no data were collected at all, an average 'per hole' coefficient, based on returned surveys from that same county, were applied. In counties where no data were collected at all, a State average 'per hole' value of 13.2 acre-feet was used as the coefficient. In 2005, Colorado had 243 turf golf courses (there are 2 sand courses in the State) that had an estimated 2.27 acre-feet per irrigated course acre, and 65 percent of the source water for these courses was surface water. Ground water, potable water (public supply), and reclaimed wastewater, either partially or wholly, were source waters for the remaining courses. Fifty-three of the 64 counties in Colorado have at least one golf course, with the greatest number of courses in Jefferson (23 courses), Arapahoe (22 courses), and El Paso Counties (20 courses). In 2005, an estimated 5,647.8 acre-feet in Jefferson County, 5,402 acre-feet in Arapahoe County, and 4,473.3 acre-feet in El Paso County were used to irrigate the turf grass.

  3. Tomato nitrogen accumulation and fertilizer use efficiency on a sandy soil, as affected by nitrogen rate and irrigation scheduling

    NARCIS (Netherlands)

    Zotarelli, L.; Dukes, M.D.; Scholberg, J.M.S.; Munoz-Carpena, R.; Icerman, J.

    2009-01-01

    Tomato production systems in Florida are typically intensively managed with high inputs of fertilizer and irrigation and on sandy soils with low inherent water and nutrient retention capacities; potential nutrient leaching losses undermine the sustainability of such systems. The objectives of this

  4. Are There Infinite Irrigation Trees?

    Science.gov (United States)

    Bernot, M.; Caselles, V.; Morel, J. M.

    2006-08-01

    In many natural or artificial flow systems, a fluid flow network succeeds in irrigating every point of a volume from a source. Examples are the blood vessels, the bronchial tree and many irrigation and draining systems. Such systems have raised recently a lot of interest and some attempts have been made to formalize their description, as a finite tree of tubes, and their scaling laws [25], [26]. In contrast, several mathematical models [5], [22], [10], propose an idealization of these irrigation trees, where a countable set of tubes irrigates any point of a volume with positive Lebesgue measure. There is no geometric obstruction to this infinitesimal model and general existence and structure theorems have been proved. As we show, there may instead be an energetic obstruction. Under Poiseuille law R(s) = s -2 for the resistance of tubes with section s, the dissipated power of a volume irrigating tree cannot be finite. In other terms, infinite irrigation trees seem to be impossible from the fluid mechanics viewpoint. This also implies that the usual principle analysis performed for the biological models needs not to impose a minimal size for the tubes of an irrigating tree; the existence of the minimal size can be proven from the only two obvious conditions for such irrigation trees, namely the Kirchhoff and Poiseuille laws.

  5. Local land-atmosphere feedbacks limit irrigation demand

    Science.gov (United States)

    Decker, Mark; Ma, Shaoxiu; Pitman, Andy

    2017-05-01

    Irrigation is known to influence regional climate but most studies forecast and simulate irrigation with offline (i.e. land only) models. Using south eastern Australia as a test bed, we demonstrate that irrigation demand is fundamentally different between land only and land-atmosphere simulations. While irrigation only has a small impact on maximum temperature, the semi-arid environment experiences near surface moistening in coupled simulations over the irrigated regions, a feedback that is prevented in offline simulations. In land only simulations that neglect the local feedbacks, the simulated irrigation demand is 25% higher and the standard deviation of the mean irrigation rate is 60% smaller. These local-scale irrigation-driven feedbacks are not resolved in coarse-resolution climate models implying that use of these tools will overestimate irrigation demand. Future studies of irrigation demand must therefore account for the local land-atmosphere interactions by using coupled frameworks, at a spatial resolution that captures the key feedbacks.

  6. Irrigation of steppe soils in the south of Russia: Problems and solutions (Analysis of Irrigation Practices in 1950-1990)

    Science.gov (United States)

    Minashina, N. G.

    2009-07-01

    Experience in irrigation of chernozems in the steppe zone of Russia for a period from 1950 to 1990 is analyzed. By the end of this period and in the subsequent years, the areas under irrigation reduced considerably, and the soil productivity worsened. This was caused by the improper design of irrigation systems, on the one hand, and by the low tolerance of chernozems toward increased moistening upon irrigation, on the other hand. The analysis of the factors and regimes of soil formation under irrigation conditions shows that irrigation-induced changes in the soil hydrology also lead to changes in the soil physicochemical, biochemical, and other properties. In particular, changes in the composition of exchangeable cations lead to the development of solonetzic process. In many areas, irrigation of chernozems was accompanied by the appearance of solonetzic, vertic, saline, and eroded soils. The development of soil degradation processes is described. In general, the deterioration of irrigated chernozems was related to the absence of adequate experience in irrigation of steppe soils, unskilled personnel, improper regime of irrigation, and excessively high rates of watering. In some cases, the poor quality of irrigation water resulted in the development of soil salinization and alkalization. To improve the situation, the training of personnel is necessary; the strategy of continuous irrigation should be replaced by the strategy of supplementary irrigation in the critical periods of crop development.

  7. Irrigation management of sigmoid colostomy.

    Science.gov (United States)

    Jao, S W; Beart, R W; Wendorf, L J; Ilstrup, D M

    1985-08-01

    Questionnaires were sent to 270 patients who had undergone abdominoperineal resection and sigmoid colostomy at the Mayo Clinic, Rochester, Minn, during the ten years from 1972 to 1982; 223 patients returned their questionnaires with evaluable data. Sixty percent of the patients were continent with irrigation, and 22% were incontinent with irrigation. Eighteen percent had discontinued irrigation for various reasons. The proportion continent was higher in women, younger patients, and previously constipated patients. A poorly constructed colostomy may cause acute angle, parastoma hernia, stomal prolapse, or stenosis and thus be the cause of failure of irrigation.

  8. Assessing the changes of groundwater recharge / irrigation water use between SRI and traditional irrigation schemes in Central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2015-04-01

    To respond to agricultural water shortage impacted by climate change without affecting rice yield in the future, the application of water-saving irrigation, such as SRI methodology, is considered to be adopted in rice-cultivation in Taiwan. However, the flooded paddy fields could be considered as an important source of groundwater recharge in Central Taiwan. The water-saving benefit of this new methodology and its impact on the reducing of groundwater recharge should be integrally assessed in this area. The objective of this study was to evaluate the changes of groundwater recharge/ irrigation water use between the SRI and traditional irrigation schemes (continuous irrigation, rotational irrigation). An experimental paddy field located in the proximal area of the Choushui River alluvial fan (the largest groundwater pumping region in Taiwan) was chosen as the study area. The 3-D finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge process and amount under traditional irrigation schemes and SRI methodology. The use of effective rainfall was taken into account or not in different simulation scenarios for each irrigation scheme. The simulation results showed that there were no significant variations of infiltration rate in the use of effective rainfall or not, but the low soil moisture setting in deep soil layers resulted in higher infiltration rate. Taking the use of effective rainfall into account, the average infiltration rate for continuous irrigation, rotational irrigation, and SRI methodology in the first crop season of 2013 were 4.04 mm/day, 4.00 mm/day and 3.92 mm/day, respectively. The groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reducing 4% and 2% compared with continuous irrigation and rotational irrigation, respectively. The field irrigation requirement amount of SRI methodology was significantly

  9. Scheduling the scheduling task : a time management perspective on scheduling

    NARCIS (Netherlands)

    Larco Martinelli, J.A.; Wiers, V.C.S.; Fransoo, J.C.

    2013-01-01

    Time is the most critical resource at the disposal of schedulers. Hence, an adequate management of time from the schedulers may impact positively on the scheduler’s productivity and responsiveness to uncertain scheduling environments. This paper presents a field study of how schedulers make use of

  10. Irrigation water management: Basic principles and applications

    OpenAIRE

    Ella, Victor B.

    2007-01-01

    This presentation defines the term, irrigation, as well as explains the common methods of irrigation in attempt to define the fundamental principles needed to wisely design an irrigation system. It outlines a typical drip irrigation set-up, and discusses management of an irrigation system, including water volume application suggestions. LTRA-5 (Agroforestry and Sustainable Vegetable Production)

  11. Modeling and assessing field irrigation water use in a canal system of Hetao, upper Yellow River basin: Application to maize, sunflower and watermelon

    Science.gov (United States)

    Ren, Dongyang; Xu, Xu; Hao, Yuanyuan; Huang, Guanhua

    2016-01-01

    Water saving in irrigation is a key issue in the upper Yellow River basin. Excessive irrigation leads to water waste, water table rising and increased salinity. Land fragmentation associated with a large dispersion of crops adds to the agro-hydrological complexity of the irrigation system. The model HYDRUS-1D, coupled with the FAO-56 dual crop coefficient approach (dualKc), was applied to simulate the water and salt movement processes. Field experiments were conducted for maize, sunflower and watermelon crops in the command area of a typical irrigation canal system in Hetao Irrigation District during 2012 and 2013. The model was calibrated and validated in three crop fields using two-year experimental data. Simulations of soil moisture, salinity concentration and crop yield fitted well with the observations. The irrigation water use was then evaluated and results showed that large amounts of irrigation water percolated due to over-irrigation but their reuse through capillary rise was also quite large. That reuse was facilitated by the dispersion of crops throughout largely fragmented field, thus with fields reusing water percolated from nearby areas due to the rapid lateral migration of groundwater. Beneficial water use could be improved when taking this aspect into account, which was not considered in previous researches. The non-beneficial evaporation and salt accumulation into the root zone were found to significantly increase during non-growth periods due to the shallow water tables. It could be concluded that when applying water saving measures, close attention should be paid to cropping pattern distribution and groundwater control in association with irrigation scheduling and technique improvement.

  12. Irrigation-based livelihood challenges and opportunities : a gendered technology of irrigation development intervention in the Lower Moshi irrigation scheme Tanzania

    NARCIS (Netherlands)

    Kissawike, K.

    2008-01-01

    This thesis is a study of a modernised irrigation scheme in Tanzania. It aims to
    understand how irrigation and agricultural technologies have interacted with local
    society to transform production, paying particular attention to gender relations and
    changes for women farmers. The

  13. Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2016-04-01

    The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for

  14. Where Does the Irrigation Water Go? An Estimate of the Contribution of Irrigation to Precipitation Using MERRA

    Science.gov (United States)

    Wei, Jiangfeng; Dirmeyer, Paul A.; Wisser, Dominik; Bosilovich, Michael G.; Mocko, David M.

    2013-01-01

    Irrigation is an important human activity that may impact local and regional climate, but current climate model simulations and data assimilation systems generally do not explicitly include it. The European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim) shows more irrigation signal in surface evapotranspiration (ET) than the Modern-Era Retrospective Analysis for Research and Applications (MERRA) because ERA-Interim adjusts soil moisture according to the observed surface temperature and humidity while MERRA has no explicit consideration of irrigation at the surface. But, when compared with the results from a hydrological model with detailed considerations of agriculture, the ET from both reanalyses show large deficiencies in capturing the impact of irrigation. Here, a back-trajectory method is used to estimate the contribution of irrigation to precipitation over local and surrounding regions, using MERRA with observation-based corrections and added irrigation-caused ET increase from the hydrological model. Results show substantial contributions of irrigation to precipitation over heavily irrigated regions in Asia, but the precipitation increase is much less than the ET increase over most areas, indicating that irrigation could lead to water deficits over these regions. For the same increase in ET, precipitation increases are larger over wetter areas where convection is more easily triggered, but the percentage increase in precipitation is similar for different areas. There are substantial regional differences in the patterns of irrigation impact, but, for all the studied regions, the highest percentage contribution to precipitation is over local land.

  15. Effective colostomy irrigation.

    Science.gov (United States)

    Mazier, W P; Dignan, R D; Capehart, R J; Smith, B G

    1976-06-01

    The ultimate goal of the cone method of colostomy irrigation is to return patients with colostomies to their former role in society with confidence in themselves to the extent that having a colostomy is not considered a handicap. The results have generally been excellent. We believe all patients with stomas should be afforded the opportunity to attempt colostomy irrigation.

  16. Potato yield and yield structure depending on irrigation

    Directory of Open Access Journals (Sweden)

    Milić Stanko

    2010-01-01

    Full Text Available In the agroclimatic conditions of the Vojvodina Province, the application of an economic water regime and modern technology is necessary for stable and intensive potato production. A two-year experiment on calcareous chernozem was carried out to determine how irrigation and different pre-irrigation soil moisture affect potato yield and distribution of tuber fraction in the potato yield. The block-design trial had four replicates and was adapted for sprinkler irrigation conditions. It included four treatments: irrigation with pre-irrigation moisture levels of 60 % of field water capacity (FC, irrigation with pre-irrigation moisture levels of 70 % (FC, irrigation with pre-irrigation moisture levels of 80% (FC, and a non-irrigated control treatment. Irrigation significantly increased the yield of potato, which increased from 37.27 % to 75.86 %. Under irrigation, the percentage of small fractions decreased in favour of the 55 mm one, or fractions above the 45-55 mm range. On average, irrigated treatments produced significantly more tubers than the conditions of natural water supply. .

  17. Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

    Science.gov (United States)

    Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

    2016-01-01

    Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

  18. Comparative study on agro-physiology of sugarcane (saccharum officinarum l.) genotypes at different irrigation co-efficient values

    International Nuclear Information System (INIS)

    Farooq, Z.; Mehmood, S.

    2015-01-01

    Drought is the primary factor limiting sugarcane growth and physiological development under the climatic conditions of Pakistan; especially in those areas where without supplemental irrigation, productivity is not possible. Lack of detailed information regarding the performance of cane varieties under drought during formative stage and poor selection breeding program played key role in limiting cane productivity. The proposed study was conducted to investigate the genetic response of different cultivars viz., CSSG-676, CSSG-668, HoSG-795, HoSG-529, NSG-59 and HSF- 240 (standard) regarding the physiological development of sugarcane and its productivity at different irrigation co-efficient levels (100%, 80% and 60%). This study elucidates that moisture has a pronounced impact on the physiological attributes of sugarcane and proper irrigation scheduling with 20 no. of irrigations were reported best in-term of better germination (69.65%), leaf area index (7.13), crop growth rate (8.44), net assimilation rate (1.06) and chlorophyll contents (5.98). Similarly in case of genomic response, NSG-59 was reported significant best as compared to all other test cultivars in term of better physiological performance, showing significant higher leaf area index, crop growth rate, chlorophyll contents and water use efficiency that maximized the crop growth and resulted in higher net assimilation rate. Higher proline contents (1.59) produced in NSG-59 also made it best under drought conditions. (author)

  19. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Science.gov (United States)

    Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P

    2015-01-01

    Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  20. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Directory of Open Access Journals (Sweden)

    Xin Liu

    Full Text Available Modelling crop evapotranspiration (ET response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1 and summer maize (scenario 2 by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  1. Performing drip irrigation by the farmer managed Seguia Khrichfa irrigation system, Morocco

    NARCIS (Netherlands)

    Kooij, van der S.

    2016-01-01

    Drip irrigation is represented in literature and agricultural policies as a modern and water saving technology. Because this technology is often associated with ‘modern’ agriculture and development, it seems out-of-place in ‘traditional’ farmer managed irrigation systems (FMIS). Thinking along

  2. Grounding the nexus: Examining the integration of small-scale irrigators into a national food security programme in Burkina Faso

    Directory of Open Access Journals (Sweden)

    Brian Dowd-Uribe

    2018-06-01

    Full Text Available The water-food nexus literature examines the synergies and trade-offs of resource use but is dominated by large-scale analyses that do not sufficiently engage the local dimensions of resource management. The research presented here addresses this gap with a local-scale analysis of integrated water and food management in Burkina Faso. Specifically, we analyse the implementation of a national food security campaign (Opération Bondofa to boost maize production in a subbasin that exhibits two important trends in Africa: a large increase in small-scale irrigators and the decentralisation of water management. As surface water levels dropped in the region, entities at different scales asserted increased control over water allocation, exposing the contested nature of new decentralised institutions, and powerful actors’ preference for local control. These scalar power struggles intersected with a lack of knowledge of small-scale irrigators’ cultural practices to produce an implementation and water allocation schedule that did match small-scale irrigator needs, resulting in low initial enthusiasm for the project. Increased attention from national governments to strengthen decentralised water management committees and spur greater knowledge of, and engagement with, small-scale irrigators can result in improved programme design to better incorporate small-scale irrigators into national food security campaigns.

  3. Biological degradation of chernozems under irrigation

    Directory of Open Access Journals (Sweden)

    Oksana Naydyonova

    2014-12-01

    Full Text Available We studied the changes in the state of microbial cenosis of Ukraine’s chernozems under irrigation. Considerable part of Ukraine’s chernozems is located in the areas where humidification is insufficient and unstable. Irrigation is a soil-reclamation measure for chernozems of Ukrainian Forest-steppe and Steppe which enables getting the assured yield, especially vegetable and fodder crops. At the same time, irrigation is a powerful anthropogenic factor that affects the soil, causes a significant transformation of many of its properties and regimes including biological ones. Often these changes are negative. The purpose of our investigation was to identify changes in the state of microbial cenoses of chernozem soils under irrigation which depend on such factors as the quality of irrigation water, the duration and intensity of irrigation, the initial properties of soil, the structure of crop rotation, usage of fertilizing systems and agroameliorative techniques. We identified direction and evaluated a degree of changes in biological properties of chernozems under influence of irrigation in different agro-irrigational and soil-climatic conditions. In the long-term stationary field experiments we identified the following biological indices of irrigated soils and their non-irrigated analogues: a number of microorganisms which belong to main ecological-trophic groups, activity of soil enzymes (dehydrogenase, invertase, phenol oxidase, soil phytotoxic activity, cellulose destroying capacity of soil, indices of oligotrophy and mineralization, summary biological index (SBI and index of biological degradation (BDI. Results of researches showed that irrigation unbalanced the soil ecosystem and stipulated the forming of microbial cenosis with new parameters. Long-term intensive irrigation of typical chernozem (Kharkiv Region with fresh water under condition of 4-fields vegetable crop rotation led to the degradation changes of its microbial cenosis such as

  4. Irrigation Analysis Based on Long-Term Weather Data

    Directory of Open Access Journals (Sweden)

    James R. Mahan

    2016-08-01

    Full Text Available Irrigation management is based upon delivery of water to a crop in the correct amount and time, and the crop’s water need is determined by calculating evapotranspiration (ET using weather data. In 1994, an ET-network was established in the Texas High Plains to manage irrigation on a regional scale. Though producers used the ET-network, by 2010 public access was discontinued. Why did producers allow a valuable irrigation-management tool to be eliminated? Our objective was to analyze the effect of declining well capacities on the usefulness of cotton ET (ETc for irrigation. Thirty years (1975–2004 of daily ETc data were used to compare irrigation demand vs. irrigation responses at four locations, analyzed for multiple years and range of well capacities for three irrigation-intervals. Results indicated that when well capacities declined to the point that over-irrigation was not possible, the lower well capacities reduced the value of ETc in terms of the number of irrigations and total amount of water applied. At well capacities <1514 L·min−1 the fraction of irrigations for which ETc information was used to determine the irrigation amount was <35% across years and irrigation intervals. The value of an ETc-based irrigation may fall into disuse when irrigation-water supplies decline.

  5. Evaluation of hydraulic performance of downstream-controlled Maira-PHLC irrigation canals under crop-based irrigation operations

    NARCIS (Netherlands)

    Munir, S.; Schultz, B.; Suryadi, F.X.; Bharati, L.

    2012-01-01

    Demand-based irrigation systems are operated according to crop water requirements. As crop water requirements remain variable throughout the growing season, the discharges in the canal also vary to meet demands. The irrigation system under study is a demand-based semi-automatic irrigation system,

  6. Role of sediment in the design and management of irrigation canals : Sunsari Morang Irrigation Scheme, Nepal

    NARCIS (Netherlands)

    Paudel, K.

    2010-01-01

    Sediment transport in irrigation canals The sediment transport aspect is a major factor in irrigation development as it determines to a large extent the sustainability of an irrigation scheme, particularly in case of unlined canals in alluvial soils. Investigations in this respect started since

  7. Newer Root Canal Irrigants in Horizon: A Review

    Directory of Open Access Journals (Sweden)

    Sushma Jaju

    2011-01-01

    Full Text Available Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

  8. [Irrigants and intracanal medicaments in endodontics].

    Science.gov (United States)

    Zehnder, Matthias; Lehnert, Birgit; Schönenberger, Kathrin; Waltimo, Tuomas

    2003-01-01

    Modern, biologic root canal therapy should be performed with suitable irrigating solutions and intracanal medicaments. The goal of endodontic treatment is to free the treated tooth from infection and prevent reinfection as thoroughly as possible by means which do not put the organism at risk. In this review of the literature, an evidence-based concept for irrigation and medication of root canal systems is presented. Irrigants and medicaments are discussed with respect to their antimicrobial, tissue-dissolving and endotoxin-decontaminating capacity in relation to their systemic toxicity. Recent findings pertaining to interactions of root canal medicaments and irrigating solutions and their impact on a sound irrigating and medicating concept are discussed.

  9. Irrigation in dose assessments models

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla; Barkefors, Catarina [Studsvik RadWaste AB, Nykoeping (Sweden)

    2004-05-01

    SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

  10. Irrigation in dose assessments models

    International Nuclear Information System (INIS)

    Bergstroem, Ulla; Barkefors, Catarina

    2004-05-01

    SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

  11. Sediment Transport Model for a Surface Irrigation System

    Directory of Open Access Journals (Sweden)

    Damodhara R. Mailapalli

    2013-01-01

    Full Text Available Controlling irrigation-induced soil erosion is one of the important issues of irrigation management and surface water impairment. Irrigation models are useful in managing the irrigation and the associated ill effects on agricultural environment. In this paper, a physically based surface irrigation model was developed to predict sediment transport in irrigated furrows by integrating an irrigation hydraulic model with a quasi-steady state sediment transport model to predict sediment load in furrow irrigation. The irrigation hydraulic model simulates flow in a furrow irrigation system using the analytically solved zero-inertial overland flow equations and 1D-Green-Ampt, 2D-Fok, and Kostiakov-Lewis infiltration equations. Performance of the sediment transport model was evaluated for bare and cropped furrow fields. The results indicated that the sediment transport model can predict the initial sediment rate adequately, but the simulated sediment rate was less accurate for the later part of the irrigation event. Sensitivity analysis of the parameters of the sediment module showed that the soil erodibility coefficient was the most influential parameter for determining sediment load in furrow irrigation. The developed modeling tool can be used as a water management tool for mitigating sediment loss from the surface irrigated fields.

  12. Bayesian Belief Networks Approach for Modeling Irrigation Behavior

    Science.gov (United States)

    Andriyas, S.; McKee, M.

    2012-12-01

    Canal operators need information to manage water deliveries to irrigators. Short-term irrigation demand forecasts can potentially valuable information for a canal operator who must manage an on-demand system. Such forecasts could be generated by using information about the decision-making processes of irrigators. Bayesian models of irrigation behavior can provide insight into the likely criteria which farmers use to make irrigation decisions. This paper develops a Bayesian belief network (BBN) to learn irrigation decision-making behavior of farmers and utilizes the resulting model to make forecasts of future irrigation decisions based on factor interaction and posterior probabilities. Models for studying irrigation behavior have been rarely explored in the past. The model discussed here was built from a combination of data about biotic, climatic, and edaphic conditions under which observed irrigation decisions were made. The paper includes a case study using data collected from the Canal B region of the Sevier River, near Delta, Utah. Alfalfa, barley and corn are the main crops of the location. The model has been tested with a portion of the data to affirm the model predictive capabilities. Irrigation rules were deduced in the process of learning and verified in the testing phase. It was found that most of the farmers used consistent rules throughout all years and across different types of crops. Soil moisture stress, which indicates the level of water available to the plant in the soil profile, was found to be one of the most significant likely driving forces for irrigation. Irrigations appeared to be triggered by a farmer's perception of soil stress, or by a perception of combined factors such as information about a neighbor irrigating or an apparent preference to irrigate on a weekend. Soil stress resulted in irrigation probabilities of 94.4% for alfalfa. With additional factors like weekend and irrigating when a neighbor irrigates, alfalfa irrigation

  13. Evaluation model development for sprinkler irrigation uniformity ...

    African Journals Online (AJOL)

    use

    Sprinkle and trickle irrigation. The. Blackburn Press, New Jersey, USA. Li JS, Rao MJ (1999). Evaluation method of sprinkler irrigation nonuniformity. Trans. CSAE. 15(4): 78-82. Lin Z, Merkley GP (2011). Relationships between common irrigation application uniformity indicators. Irrig Sci. Online First™, 27 January. 2011.

  14. Survey the Effects of Partial Root Zone Deficit Irrigation and Deficit Irrigation on Quantitative, Qualitative and Water Use Efficiency of Pomegranate

    Directory of Open Access Journals (Sweden)

    mohammad saeed tadaion

    2017-12-01

    Full Text Available Introduction: One of the latest efficient methods on increment of water use efficiency that confirmed by many scientists all over the world is deficit and alternative partial root zone deficit irrigation. In this experiment the effect of deficit and alternative partial root zone deficit irrigation on fruit yield, quality and water use efficiency of pomegranate (Punicagranatum (L. cv. Zarde-anar were investigatedin Arsenjan semi-arid region. Materials and Methods: The experiment was carried out in a constant plots and randomized complete block design (RCBD with four replicationsin five years.Treatmentswere 1- full flood irrigation (100 percent crop water requirement (T1 2- flood irrigation with 100 percent crop water requirement as alternate partial root-zone irrigation(every irrigation conducted on one side of tree (T2 3- flood irrigation with 50 percent crop water requirement as regular deficit irrigation (T3 4- full two-side drip irrigation(with regard to crop water requirement (eight drippers with twolit/hour flow by two different individual networks (T4 5- alternate partial root-zone drip irrigation with 100 percent crop water requirement (T5 6- regular deficit drip irrigation with 50 percent crop water requirement (T6 in every irrigation period. Each experimental treatment includes four trees and 96 similar twelve years old trees overall. Cultivation practice was conducted similarly on all of the trees. Results and Discussion: Results showed that the highest yield and water use efficiency based on statistical analysis belong to both PRD treatments i.e. alternate partial root-zone drip irrigation with 100 percent crop water requirement and alternate partial root-zone flood irrigation with 100 percent crop water requirement, respectively, that both of them decreased water requirement for irrigation up to 35 and 50 percent in comparison tocontrol. Application of partial root drying irrigation on both traditional flood irrigation and drip

  15. Sustainable Irrigation Allocation Model for Dry and Wet Periods using Reservoir Storage and Inflow

    Science.gov (United States)

    Surianarayanan, S.; Suribabu, C. R.; Ramakrishnan, K.

    2017-07-01

    The dry period agriculture is inevitable both for the farmers for their earning, and for the soil for its fertility by crop-rotation. In tropical countries like INDIA, dry period agriculture becomes difficult because of less (or) no rain fall. Hence a simple water balancing model for irrigation scheduling, using the measure “Volumetric Reliability” is prepared in this paper, with the storage and inflow of a reservoir both for the dry and wet periods. The case-study is done for a reservoir in INDIA with thirty one years of hydrological data(from 1982 to 2012). The objective of this paper is to prepare a simple water balance model taking 10 days periods of demand and supply for ID crop(Irrigated Dry crop, ground nut) with usage of volumetric reliability concept for the periods of deficiency and adoption of less water requirement crops to reduce the water-stress during critical periods of crop growth, and finally arrive at a feasible allocation schedule for the success of agriculture and the yield throughout the year both for wet and dry crops with the available storage on the start of irrigation for a particular year. The reservoir is divided for storages such as full, deficient and critical storages. The starting storage for the dry period from January is used after adequate allocation for wet crops, the quantity for riparian rights and for drinking water, for the sustainability. By the water-balancing, the time-series for thirty one years, it is found that for twenty two years the demand for the ID crops is satisfied with the storage in the reservoir, and in the remaining years of deficient inflows, for three years (1986,1996,2004)the demand is managed by using the safe reliability factor for demand which can nullify the deficit in demand for the whole supply period. But it is genuine to assure that the reduction in the amount of water for each 10 days periods should not exceed the survival limit of the crop. Necessary soil-moisture must be ensured in the crop

  16. Irrigation as an Historical Climate Forcing

    Science.gov (United States)

    Cook, Benjamin I.; Shukla, Sonali P.; Puma, Michael J.; Nazarenko, Larissa S.

    2014-01-01

    Irrigation is the single largest anthropogenic water use, a modification of the land surface that significantly affects surface energy budgets, the water cycle, and climate. Irrigation, however, is typically not included in standard historical general circulation model (GCM) simulations along with other anthropogenic and natural forcings. To investigate the importance of irrigation as an anthropogenic climate forcing, we conduct two 5-member ensemble GCM experiments. Both are setup identical to the historical forced (anthropogenic plus natural) scenario used in version 5 of the Coupled Model Intercomparison Project, but in one experiment we also add water to the land surface using a dataset of historically estimated irrigation rates. Irrigation has a negligible effect on the global average radiative balance at the top of the atmosphere, but causes significant cooling of global average surface air temperatures over land and dampens regional warming trends. This cooling is regionally focused and is especially strong in Western North America, the Mediterranean, the Middle East, and Asia. Irrigation enhances cloud cover and precipitation in these same regions, except for summer in parts of Monsoon Asia, where irrigation causes a reduction in monsoon season precipitation. Irrigation cools the surface, reducing upward fluxes of longwave radiation (increasing net longwave), and increases cloud cover, enhancing shortwave reflection (reducing net shortwave). The relative magnitude of these two processes causes regional increases (northern India) or decreases (Central Asia, China) in energy availability at the surface and top of the atmosphere. Despite these changes in net radiation, however, climate responses are due primarily to larger magnitude shifts in the Bowen ratio from sensible to latent heating. Irrigation impacts on temperature, precipitation, and other climate variables are regionally significant, even while other anthropogenic forcings (anthropogenic aerosols

  17. Root canal debris removal using different irrigating needles: An SEM study

    Directory of Open Access Journals (Sweden)

    Sheetal Ghivari

    2011-01-01

    Full Text Available Aim: This study was carried out to compare the efficacy of three irrigating needle designs in removal of debris from different parts of the root canal. Materials and Methods: Thirty human maxillary canines were prepared using HERO Shaper rotary system and irrigated with 1 ml of 5.25% sodium hypochlorite (NaOCl after each instrument change. Three 25-gauge irrigation needle designs - brush-covered Navi Tip FX (Group I, side-vented needle RC Twents (Group II and single-beveled (Group III irrigating needles - were tested for their efficiency in debris removal in three different parts of the root canal (n=10 canals per group. Following instrumentation, the roots were vertically sectioned and divided into coronal, middle and apical thirds for observation under scanning electron microscope (×200 magnification. Debris on the canal wall was evaluated by using a four-scale scoring system described by Paque and his co-workers. Results: The canals irrigated with brush-covered needle Navi Tip FX (Group I showed lower average debris score, indicating greater removal of debris in coronal third as compared to middle and apical thirds, whereas the canals irrigated with side-vented needle (Group II and single-beveled needle (Group III exhibited lower average score in the middle third than coronal and apical thirds. All the three needle designs exhibited higher debris score in apical third of the root canal. Tukey multiple comparisons test was applied at a significance level of P>0.05. A statistically significant difference (P<0.05 was observed in the debris removal in the coronal and middle thirds of root canals irrigated with brush-covered Navi Tip FX (Group I and side-vented (Group II needles, respectively, when compared with other needle design groups. Conclusion: Within the limitations of this study, it can be concluded that all the needle designs tested were effective in certain regions of the root canal with apical third uncleaned. Side-vented needle by

  18. Crop scheduling improvements for rainfed agriculture in the high jungle of Peru

    Directory of Open Access Journals (Sweden)

    Enrique Meseth

    2014-12-01

    Full Text Available This work was aimed to improve the water management for agriculture by applying efficient crop schedules in Vilcabamba and similar areas of the high jungle, which can satisfy most of the water requirements with rainfed agriculture to maximize the crops yield. For this purpose, two field practices were carried out during the dry (September 2012 and wet season (February 2013 to measure rivers and canals flows with the velocity/area method; 19 soil samples were collected on-site and analyzed, presenting prevalent sandy loam and loam textures. Cropwat program was used to estimate crop water requirements and scheme irrigation requirements, resulting in a maximum flow capacity of 1.72 l s-1 in May, during the dry season. The flow capacity can be satisfied, since small ditches convey approximately 2 to 6 l s-1 on the same season. The research findings indicate that rainfed farming can be practised, yet an initial pre-irrigation needs to be applied, for crops should not be water stressed. However, if soil is not pre-irrigated the production can be affected, with vegetables and potato crop yields being reduced by 4.7% and 1.4% respectively. To minimize these effects, both crops are suggested to be sowed one month later, adapting their growth period to the rainy season.

  19. Colostomy irrigation: are we offering it enough?

    Science.gov (United States)

    Woodhouse, Fran

    This article discusses the use of irrigation for suitable colostomists and reasons why it can have a very positive effect on lifestyle. While it is evidence-based it also includes anecdotal tips from patients who irrigate. The suitability of patients to irrigate and ways to 'get started' with irrigation are discussed.

  20. A scintigraphic study of colostomy irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Shinji; Fujii, Hisao; Nakano, Hiroshige (Nara Medical Univ., Kashihara (Japan))

    1991-09-01

    Colostomy irrigation was investigated by colonoscintigraphy. Twelve rectal cancer and one sigmoid colon cancer patients were examined. The tepid water whose volume was determined by barium enema was mixed with {sup 99m}Tc-DTPA. Dynamic scanning was started on commencement of colostomy irrigation. The sampling time was 3 seconds and scanning was performed for 30 minutes. The mean volume of remnant colon as measured by barium enema was 650 ml. The mean number of mass movements was 4.3. The mean evacuation time was 11 minutes 56 seconds and the mean half emptying time was calculated to be 9.5 minutes. The evacuation time in the patients who underwent colostomy irrigation for more than 2 years was greater than that in the patients who underwent irrigation for less than 2 years. Colonic motility was thought to have weakened. The half emptying time and the number of mass movements in the patients whose irrigation water went into the terminal ileum was more than that in the patients whose irrigation water was within the colon and cecum. Irrigation water which went into the terminal ileum was caused evacuation after the contents of the remnant colon were washed out. In conclusion, patients should have their colostomy irrigated with the tepid water, volume is determined by barium enema. Furthermore single infusion of the water is recommended. (author).

  1. A scintigraphic study of colostomy irrigation

    International Nuclear Information System (INIS)

    Yasuda, Shinji; Fujii, Hisao; Nakano, Hiroshige

    1991-01-01

    Colostomy irrigation was investigated by colonoscintigraphy. Twelve rectal cancer and one sigmoid colon cancer patients were examined. The tepid water whose volume was determined by barium enema was mixed with 99m Tc-DTPA. Dynamic scanning was started on commencement of colostomy irrigation. The sampling time was 3 seconds and scanning was performed for 30 minutes. The mean volume of remnant colon as measured by barium enema was 650 ml. The mean number of mass movements was 4.3. The mean evacuation time was 11 minutes 56 seconds and the mean half emptying time was calculated to be 9.5 minutes. The evacuation time in the patients who underwent colostomy irrigation for more than 2 years was greater than that in the patients who underwent irrigation for less than 2 years. Colonic motility was thought to have weakened. The half emptying time and the number of mass movements in the patients whose irrigation water went into the terminal ileum was more than that in the patients whose irrigation water was within the colon and cecum. Irrigation water which went into the terminal ileum was caused evacuation after the contents of the remnant colon were washed out. In conclusion, patients should have their colostomy irrigated with the tepid water, volume is determined by barium enema. Furthermore single infusion of the water is recommended. (author)

  2. Effectiveness of various irrigation activation protocols and the self-adjusting file system on smear layer and debris removal.

    Science.gov (United States)

    Çapar, İsmail Davut; Aydinbelge, Hale Ari

    2014-01-01

    The purpose of the present study is to evaluate smear layer generation and residual debris after using self-adjusting file (SAF) or rotary instrumentation and to compare the debris and smear layer removal efficacy of the SAF cleaning/shaping irrigation system against final agitation techniques. One hundred and eight maxillary lateral incisor teeth were randomly divided into nine experimental groups (n = 12), and root canals were prepared using ProTaper Universal rotary files, with the exception of the SAF instrumentation group. During instrumentation, root canals were irrigated with a total of 16 mL of 5% NaOCl. For final irrigation, rotary-instrumented groups were irrigated with 10 mL of 17% EDTA and 10 mL of 5% NaOCl using different irrigation agitation regimens (syringe irrigation with needles, NaviTip FX, manual dynamic irrigation, CanalBrush, EndoActivator, EndoVac, passive ultrasonic irrigation (PUI), and SAF irrigation). In the SAF instrumentation group, root canals were instrumented for 4 min at a rate of 4 mL/min with 5% NaOCl and received a final flush with same as syringe irrigation with needles. The surface of the root dentin was observed using a scanning electron microscope. The SAF instrumentation group generated less smear layer and yielded cleaner canals compared to rotary instrumentation. The EndoActivator, EndoVac, PUI, and SAF irrigation groups increased the efficacy of irrigating solutions on the smear layer and debris removal. The SAF instrumentation yielded cleaner canal walls when compared to rotary instrumentation. None of the techniques completely removed the smear layer from the root canal walls. © 2014 Wiley Periodicals, Inc.

  3. Soil salinity under deficit drip irrigation of potato and millet in in an arid environment

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2017-06-01

    received rainfall. For millet experiments, salinity was lowest under emitters and highest midway to the margin of wetted bands and higher soil salinity was maintained in the root zone with deficit irrigation treatments than full irrigation. Millet and potato yields were highest under Full treatment. Yields decreased almost linearly when applied water was reduced. However, reduction in quality was significantly important for DI60 and DI40. The analysis outcome of the crops sensitivity to salt indicated respectively for autumn, winter and spring potato and millet crops that thresholds are close to the value calculated from published salt tolerance data (1.9, 1.55, 1.85 vs. 1.7 dS/m for potato and 3.46 vs. 3.65 dS/m for millet but the slopes are considerably steeper (34, 54, 47 vs. 12%; 17 vs. 6.7%, apparently because of the combined effect of salinity and water stresses. The results provide information’s to farmers for formulating improved planning regarding irrigation management practices. The results support the practicality of using the full irrigation (100% of ETc methodology to optimize irrigation with saline water for potato and millet production and to control soil salinity. Under situations of water shortage, the deficit irrigation strategy (DI80 and DI60 is recommended as a tool to schedule irrigation of potato and millet crops in arid regions of Tunisia.

  4. Calibration and validation of the STICS crop model for managing wheat irrigation in the semi-arid Marrakech/Al-Haouz Plain

    International Nuclear Information System (INIS)

    Hadria, R.; Khabba, S.; Lahrouni, A.; Duchemin, B.; Chehbouni, A.; Carriou, J.; Ouzine, L.

    2007-01-01

    In the first part of this work, we shoot growth module and grain yield of the STICS crop model were calibrated and validated by using field data which was collected from irrigated winter wheat fields in the Haouz plain near Marrakech. The calibration was performed on the thermal units between the four phonological stages that control the dynamics of leaf area index and thermal unit between emergence and beginning of grain filling. The plant phenology was calibrated for three fields monitored during the 2002/03 season. Evaluation of the green yields and the temporal evolution of leaf area index were done for six validation fields during 2003/04. The results showed the significant accuracy of the model in simulating these variables and also indicated that the plants mainly suffered from lack of nitrogen. The results in the second part show the potential of crop modeling to schedule irrigation water, on the assumption that the plants were growing under optimal conditions of fertilization. In this case, the model was used to manage the time of irrigation according to a threshold for water deficit. Various simulations displayed logical trends in the relationship between the grain yield and both the amount and timing of irrigation water. These results were finally compared with those obtained from real irrigation practices. For the particular climate pf 2003/04, the comparison showed that 70mm 40 mm of water could be saved in case of early and late showing, respectively. (author)

  5. Impacts of Irrigation on the Heat Fluxes and Near-Surface Temperature in an Inland Irrigation Area of Northern China

    Directory of Open Access Journals (Sweden)

    Li Jiang

    2014-03-01

    Full Text Available Irrigated agriculture has the potential to alter regional to global climate significantly. We investigate how irrigation will affect regional climate in the future in an inland irrigation area of northern China, focusing on its effects on heat fluxes and near-surface temperature. Using the Weather Research and Forecasting (WRF model, we compare simulations among three land cover scenarios: the control scenario (CON, the irrigation scenario (IRR, and the irrigated cropland expansion scenario (ICE. Our results show that the surface energy budgets and temperature are sensitive to changes in the extent and spatial pattern of irrigated land. Conversion to irrigated agriculture at the contemporary scale leads to an increase in annual mean latent heat fluxes of 12.10 W m−2, a decrease in annual mean sensible heat fluxes of 8.85 W m−2, and a decrease in annual mean temperature of 1.3 °C across the study region. Further expansion of irrigated land increases annual mean latent heat fluxes by 18.08 W m−2, decreases annual mean sensible heat fluxes by 12.31 W m−2, and decreases annual mean temperature by 1.7 °C. Our simulated effects of irrigation show that changes in land use management such as irrigation can be an important component of climate change and need to be considered together with greenhouse forcing in climate change assessments.

  6. Agriculture Irrigation and Water Use

    OpenAIRE

    Bajwa, Rajinder S.; Crosswhite, William M.; Hostetler, John E.; Wright, Olivia W.; United States Department of Agriculture, Economic Research Service

    1992-01-01

    The 17 Western States, plus Arkansas, Florida, and Louisiana, account for 91 percent of all U.S. irrigated acreage, with the Western States alone contributing over 85 percent. This report integrates data on the distribution, characteristics, uses, and management of water resources from a wide variety of data sources. The report includes charts and tables on water use in irrigation; farm data comparing selected characteristics of irrigated and nonirrigated farms; and data on water applicatio...

  7. Water productivity analysis of sand dams irrigation farming in northern Ethiopia

    Directory of Open Access Journals (Sweden)

    Lorenzo Villani

    2018-06-01

    Full Text Available Water scarcity in drylands is the main problem that has to be tackled by farmers and practitioners that work in these areas. Climate change and increased and wealthier population are expected to put additional stress on the water resource. A large number of studies is calling to focus efforts to enhance water productivity (WP, and one of the most promising option is represented by water harvesting, the collection and storage of runoff water to be used for beneficially uses. Among the available technologies, sand dams are experiencing a renovated interest because of their relative simplicity and their potential. This research aims to deepen the knowledge about WP of water harvesting systems studying a sand dam irrigation system in Tigray, north Ethiopia, where farmers are getting used to this new technology. The research was carried out in the period March-April 2017, when farmers use sand dams water to irrigate off-season maize. We analysed a representative plot irrigated through a shallow well drilled in the sand dam aquifer, in terms of yield, Crop Water Productivity (CWP, Crop Water Productivity based on Evapotranspiration (CWP(ET and Economic Water Productivity (EWP, through field data analysis and a validated Aquacrop model. CWP(ET was found to be low (1.12 kg of grain per m3 of evapotranspired water, due by both inefficient water application and low soil fertility. Aquacrop model results showed that changing the irrigation schedule can increase CWP(ET up to 1.35 kg/m3 and EWP up to 3.94 birr/m3, but yield gap is mainly due to the low soil fertility. Interventions on soil fertility can raise yields from the original 3.3 up to 8.5 kg/ha, and thus CWP(ET and EWP up to 2.94 kg/m3 and 9.54 birr/m3 respectively. To enhance the effect of sand dams in northern Ethiopia, a set of measures, including conservation agriculture, is then proposed.

  8. Online decision support system for surface irrigation management

    Science.gov (United States)

    Wang, Wenchao; Cui, Yuanlai

    2017-04-01

    Irrigation has played an important role in agricultural production. Irrigation decision support system is developed for irrigation water management, which can raise irrigation efficiency with few added engineering services. An online irrigation decision support system (OIDSS), in consist of in-field sensors and central computer system, is designed for surface irrigation management in large irrigation district. Many functions have acquired in OIDSS, such as data acquisition and detection, real-time irrigation forecast, water allocation decision and irrigation information management. The OIDSS contains four parts: Data acquisition terminals, Web server, Client browser and Communication system. Data acquisition terminals are designed to measure paddy water level, soil water content in dry land, ponds water level, underground water level, and canals water level. A web server is responsible for collecting meteorological data, weather forecast data, the real-time field data, and manager's feedback data. Water allocation decisions are made in the web server. Client browser is responsible for friendly displaying, interacting with managers, and collecting managers' irrigation intention. Communication system includes internet and the GPRS network used by monitoring stations. The OIDSS's model is based on water balance approach for both lowland paddy and upland crops. Considering basic database of different crops water demands in the whole growth stages and irrigation system engineering information, the OIDSS can make efficient decision of water allocation with the help of real-time field water detection and weather forecast. This system uses technical methods to reduce requirements of user's specialized knowledge and can also take user's managerial experience into account. As the system is developed by the Browser/Server model, it is possible to make full use of the internet resources, to facilitate users at any place where internet exists. The OIDSS has been applied in

  9. Colonic irrigation for defecation disorders after dynamic graciloplasty.

    Science.gov (United States)

    Koch, Sacha M; Uludağ, Ozenç; El Naggar, Kadri; van Gemert, Wim G; Baeten, Cor G

    2008-02-01

    Dynamic graciloplasty (DGP) improves anal continence and quality of life for most patients. However, in some patients, DGP fails and fecal incontinence is unsolved or only partially improved. Constipation is also a significant problem after DGP, occurring in 13-90%. Colonic irrigation can be considered as an additional or salvage treatment for defecation disorders after unsuccessful or partially successful DGP. In this study, the effectiveness of colonic irrigation for the treatment of persistent fecal incontinence and/or constipation after DGP is investigated. Patients with defecation disorders after DGP visiting the outpatient clinic of the University Hospital Maastricht were selected for colonic irrigation as additional therapy or salvage therapy in the period between January 1999 and June 2003. The Biotrol(R) Irrimatic pump or the irrigation bag was used for colonic irrigation. Relevant physical and medical history was collected. The patients were asked to fill out a detailed questionnaire about colonic irrigation. Forty-six patients were included in the study with a mean age of 59.3 +/- 12.4 years (80% female). On average, the patients started the irrigation 21.39 +/- 38.77 months after the DGP. Eight patients started irrigation before the DGP. Fifty-two percent of the patients used the irrigation as additional therapy for fecal incontinence, 24% for constipation, and 24% for both. Irrigation was usually performed in the morning. The mean frequency of irrigation was 0.90 +/- 0.40 times per day. The mean amount of water used for the irrigation was 2.27 +/- 1.75 l with a mean duration of 39 +/- 23 min. Four patients performed antegrade irrigation through a colostomy or appendicostomy, with good results. Overall, 81% of the patients were satisfied with the irrigation. Thirty-seven percent of the patients with fecal incontinence reached (pseudo-)continence, and in 30% of the patients, the constipation completely resolved. Side effects of the irrigation were

  10. The Impact of Regular and Periodic Irrigation on the Fertility and Productivity of an Ordinary Chernozem of the Azov Irrigation System

    Science.gov (United States)

    Shchedrin, V. N.

    2016-02-01

    The effect of regular and periodic irrigation on the fertility and productivity of an ordinary chernozem cultivated under different conditions within the same cereal-fodder crop rotation is discussed. The investigation object is located in the area of the Azov irrigation system on the second terrace of the Don River in Rostov oblast. Irrigation water for the system is taken from the Veselovsk water reservoir. Its salinity is 1.7-2.1 g/dm3, and the salt composition is sulfate-sodium. The field experiments were performed in 2006-2013 on three experimental plots. Two of them were regularly irrigated; the third plot was periodically irrigated with alternation of 2-year-long periods with and without irrigation. Our study proved that periodic irrigation could be applied in the chernozemic zone. This new irrigation mode contributes to the preservation of the natural soil-forming process and stops the development of unfavorable processes typical of the lands irrigated with water of inadequate quality. In eight years of cultivation of the ordinary chernozem with periodic irrigation, the soil humus content increased by 10% (from 3.80 to 4.15%), and the yield reached 66.0 t/ha of fodder units. This was 9% higher than the yield obtained upon regular irrigation without agroameliorative measures and 12% lower than the yield upon regular irrigation in combination with soil-protective measures. Our data suggest that periodic irrigation is promising for the chernozemic zone, because it ensures lower water loads and preservation of the irrigated chernozems.

  11. 21 CFR 876.5895 - Ostomy irrigator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ostomy irrigator. 876.5895 Section 876.5895 Food... DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5895 Ostomy irrigator. (a) Identification. An ostomy irrigator is a device that consists of a container for fluid, tubing with a cone-shaped...

  12. Soil water movement in the unsaturated zone of an inland arid region: Mulched drip irrigation experiment

    Science.gov (United States)

    Han, Dongmei; Zhou, Tiantian

    2018-04-01

    Agricultural irrigation with trans-basin water diversion can effectively relieve the water paucity in arid and semi-arid regions, however, this may be accompanied by eco-environmental problems (e.g., saline soils, rising groundwater levels, water quality problems). The mechanism of soil water movement under irrigation in the unsaturated zone of arid regions is a key scientific problem that should be solved in order to evaluate agricultural water management and further improve current irrigation practices. This study investigated the impact of drip irrigation on soil water movement in the unsaturated zone of a cotton field in an inland arid region (the Karamay Agricultural Development Area), northwest China. Combining in situ observational physical data with temporal variation in stable isotopic compositions of soil water, we described the soil water flow system and mechanism in severe (Plot 1) and mild (Plot 2) saline-alkali cotton fields. The infiltration depths are 0-150 cm for both plots. Drip irrigation scheduling makes no significant contribution to local groundwater recharge, however, groundwater can move into the unsaturated zone through capillary rise during cotton flowering and boll periods. Plot 2 is less prone to having secondary soil salinization than Plot 1 due to the existence of a middle layer (approximately 100 cm thick), which elongated the distance between the root zone and aquifer. Rise in the water table (approximately 60 cm for Plot 1 and 50 cm for Plot 2) could be caused by lateral groundwater flow instead of vertical infiltration. We estimated the soil water storage changes in the unsaturated zone and proposed a conceptual model for deciphering the movement process of soil water. This study provides a scientific basis for determining the rise of groundwater levels and potential development of saline soils and improving agricultural water management in arid regions.

  13. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    International Nuclear Information System (INIS)

    Antonijevic, Djordje; Milovanovic, Petar; Brajkovic, Denis; Ilic, Dragan; Hahn, Michael; Amling, Michael; Rakocevic, Zlatko; Djuric, Marija; Busse, Björn

    2015-01-01

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  14. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Antonijevic, Djordje; Milovanovic, Petar [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Brajkovic, Denis [Department of Dentistry, Faculty of Medical Sciences, University of Kragujevac, Kragujevac (Serbia); Ilic, Dragan [Department of Restorative Medicine, School of Dental Medicine, University of Belgrade, Belgrade (Serbia); Hahn, Michael; Amling, Michael [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany); Rakocevic, Zlatko [Laboratory for Atomic Physics, Institute for Nuclear Science “Vinca”, University of Belgrade, Belgrade (Serbia); Djuric, Marija [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Busse, Björn, E-mail: b.busse@uke.uni-hamburg.de [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany)

    2015-11-15

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  15. 75 FR 43958 - Turlock Irrigation District and Modesto Irrigation District; Notice of Application for Amendment...

    Science.gov (United States)

    2010-07-27

    ... to the Turlock Irrigation District's Tuolumne Substation; (2) 23-mile-long, 69-kV Don Pedro-Hawkins Line extending from the Don Pedro switchyard to the Turlock Irrigation District's Hawkins Substation...

  16. Measuring Transpiration to Regulate Winter Irrigation Rates

    Energy Technology Data Exchange (ETDEWEB)

    Samuelson, Lisa [Auburn University

    2006-11-08

    Periodic transpiration (monthly sums) in a young loblolly pine plantation between ages 3 and 6 was measured using thermal dissipation probes. Fertilization and fertilization with irrigation were better than irrigation alone in increasing transpiration of young loblolly pines during winter months, apparently because of increased leaf area in fertilized trees. Irrigation alone did not significantly increase transpiration compared with the non-fertilized and non-irrigated control plots.

  17. Management of poor quality irrigation water

    International Nuclear Information System (INIS)

    Change, M.H.; Leghari, A.M.; Sipio, Q.A.

    2000-01-01

    The effect of poor quality drainage effluent on moderately saline sodic, medium textured soil at different growth stages of wheat and cotton is reported. The irrigation treatments were: I) All canal irrigations, II) one irrigation of 75 mm with saline drainage effluent (EC = 3 dS m1) after four weeks sowing of the crop, III) one irrigation of 75 mm with saline drainage effluent after seven weeks sowing of the crop, and IV) one irrigation of 75 mm with saline drainage effluent after ten weeks sowing of the crop. The treatments receiving saline water gave significant decrease in crop yields as compared to canal irrigation treatment. The higher yield of wheat and seed cotton was recorded T1 followed by T2, T3 and T4. The trend of produce was T1< T2< T3< T4 respectively. Electrical conductivity of the soil (Ece) in T1 was decreased and in other three treatments was increased, whereas, pH decreased in T1 and T2. The SAR of soil decreased in all the treatments as compared with initial values. Treatment receiving an irrigation with saline water after four weeks of sowing (T2) was better in reducing soil salinity as compared to treatments receiving such water after 7 or 10 weeks os sowing. Poor quality water (EC = 3 d Sm/sup -1/) can be managed for irrigation after four weeks of swing of crops provided certain soil and water management practices like good seed bed preparation and proper drainage measures are adopted. (author)

  18. Effects of surface and subsurface drip irrigation regimes with saline water on yield and water use efficiency of potato in arid conditions of Tunisia

    Directory of Open Access Journals (Sweden)

    Fathia El Mokh

    2014-12-01

    significant advantage on yield and WUE and reduces the soil salinity compared to the SDI in potato production under experimental conditions. The SSDI and FI100 irrigation techniques seem to optimize the use of saline water in potato production and to control soil salinity. Under situations of water shortage, adopting deficit irrigation treatment (DI60 could be an alternative for irrigation scheduling of spring and autumn potato under the arid conditions of southern Tunisia.

  19. The material of the social: the mutual shaping of institutions by irrigation technology and society in Seguia Khrichfa, Morocco

    Directory of Open Access Journals (Sweden)

    Saskia van der Kooij

    2015-03-01

    Full Text Available In this paper we draw attention to the important role technology plays in co-mediating institutions, opening up some courses of action and closing off others. Irrigation studies generally recognize the importance of institutions in making technologies work, but tend to take the precise functioning of institutions for granted. Studies that analyse institutions often do not pay enough attention to the mediating role of technology in allocating benefits, risks and burdens. We show in this paper that (irrigation institutions are moulded by and come about through the interactions between the technical and the social in dynamic and often contested processes of adaptation to changing environments. We argue that a critical understanding of what institutions do requires more explicit and detailed attention to technologies. We base this argument on a detailed historical analysis of the functioning of Seguia Khrichfa, a farmer managed irrigation scheme in Morocco. Through time, irrigation institutions in the Seguia Khrichfa have undergone transformations to match the changing demands of a heterogeneous and growing group of irrigators, an increased command area and changing cropping patterns, and the introduction of new technologies such as drip irrigation. These institutional transformations consisted of recursive cycles of modifications in technological infrastructure and the rules of allocation and distribution. Technical adaptations prompt alterations in the water rotation schedule and vice versa. We anchor our case in descriptions of a specific technology that played a crucial role in co-steering institutional change: the introduction of open/closed gates. Our analysis of the co-evolution of society and technology in shaping institutions in the Seguia Khrichfa shows how technologies become enrolled in (sometimes implicit processes of re-negotiating relations of authority and responsibility while obscuring institutional politics.

  20. Uncertainties in modelling the climate impact of irrigation

    Science.gov (United States)

    de Vrese, Philipp; Hagemann, Stefan

    2017-11-01

    Irrigation-based agriculture constitutes an essential factor for food security as well as fresh water resources and has a distinct impact on regional and global climate. Many issues related to irrigation's climate impact are addressed in studies that apply a wide range of models. These involve substantial uncertainties related to differences in the model's structure and its parametrizations on the one hand and the need for simplifying assumptions for the representation of irrigation on the other hand. To address these uncertainties, we used the Max Planck Institute for Meteorology's Earth System model into which a simple irrigation scheme was implemented. In order to estimate possible uncertainties with regard to the model's more general structure, we compared the climate impact of irrigation between three simulations that use different schemes for the land-surface-atmosphere coupling. Here, it can be shown that the choice of coupling scheme does not only affect the magnitude of possible impacts but even their direction. For example, when using a scheme that does not explicitly resolve spatial subgrid scale heterogeneity at the surface, irrigation reduces the atmospheric water content, even in heavily irrigated regions. Contrarily, in simulations that use a coupling scheme that resolves heterogeneity at the surface or even within the lowest layers of the atmosphere, irrigation increases the average atmospheric specific humidity. A second experiment targeted possible uncertainties related to the representation of irrigation characteristics. Here, in four simulations the irrigation effectiveness (controlled by the target soil moisture and the non-vegetated fraction of the grid box that receives irrigation) and the timing of delivery were varied. The second experiment shows that uncertainties related to the modelled irrigation characteristics, especially the irrigation effectiveness, are also substantial. In general the impact of irrigation on the state of the land

  1. Comparison of positive-pressure, passive ultrasonic, and laser-activated irrigations on smear-layer removal from the root canal surface.

    Science.gov (United States)

    Sahar-Helft, Sharonit; Sarp, Ayşe Sena Kabaş; Stabholtz, Adam; Gutkin, Vitaly; Redenski, Idan; Steinberg, Doron

    2015-03-01

    The purpose of this study was to compare the efficacy of three irrigation techniques for smear-layer removal with 17% EDTA. Cleaning and shaping the root canal system during endodontic treatment produces a smear layer and hard tissue debris. Three irrigation techniques were tested for solution infiltration of this layer: positive-pressure irrigation, passive ultrasonic irrigation, and laser-activated irrigation. Sixty extracted teeth were divided into six equal groups; 17% EDTA was used for 60 sec irrigation of five of the groups. The groups were as follows: Group 1, treated only with ProTaper™ F3 Ni-Ti files; Group 2, positive-pressure irrigation, with a syringe; Group 3, passive ultrasonic irrigation, inserted 1 mm short of the working length; Group 4, passive ultrasonic irrigation, inserted in the upper coronal third of the root; Group 5, Er:YAG laser-activated irrigation, inserted 1 mm short of the working length; and Group 6, Er:YAG laser-activated irrigation, inserted in the upper coronal third of the root. Scanning electron microscopy showed that the smear layer is removed most efficiently using laser-activated irrigation at low energy with 17% EDTA, inserted either at the working length or only in the coronal upper third of the root. Amounts of Ca, P, and O were not significantly different on all treated dentin surfaces. Smear-layer removal was most effective when the root canals were irrigated using Er:YAG laser at low energy with 17% EDTA solution. Interestingly, removal of the smear layer along the entire canal was similar when the laser was inserted in the upper coronal third and at 1 mm short of the working length of the root canal. This effect was not observed with the ultrasonic and positive-pressure techniques.

  2. Evaluation of Modern Irrigation Techniques with Brackish Water

    OpenAIRE

    Aboulila, Tarek Selim

    2012-01-01

    Modern irrigation techniques are becoming increasingly important in water-scarce countries especially in arid and semiarid regions. Higher crop production and better water use efficiency are usually achieved by drip irrigation as compared to other irrigation methods. Furthermore, by using drip irrigation simultaneously with brackish irrigation water, some of the water stress due to shortage of fresh water resources can be managed. The objective of the current study was to investigate the infl...

  3. Evaluation some Forage Legumes in Limited Irrigation Condition

    Directory of Open Access Journals (Sweden)

    Hassan Moniri Far

    2015-11-01

    Full Text Available Forage legumes respond differently to limited irrigation regimes. Their evaluation may, thus, help to select drought tolerant types for limited irrigation conditions. In this study four type of forage legume were studied for two years in Tikma-Dash Research Station of East Azarbaijan Agricultural and Natural Research Center, Tabriz, Iran, in a randomized complete block design using split-plot experiment in 2011-2013 years. Irrigation regimes (without irrigation, one irrigation and two irrigations were assigned to main plots and four forage types (hairy vetch, grass pea, Pannonica sativa and lathyrus were assigned to subplots. The results of analysis of variance showed that the effect of irrigation on plant height, number of shoots, leaf area and plant fresh and dry weights were not significant. Howere, legume types affected these traits significantly (P≤0.01. The effect of irrigation levels and legume types on protein content of hay were significant (P

  4. Effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin

    Directory of Open Access Journals (Sweden)

    Flávia Emi Razera BALDASSO

    2017-05-01

    Full Text Available Abstract This study aimed to evaluate the effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin. Sixty root canals from mandibular incisors were instrumented and randomly divided into six groups (n = 10 according to the irrigant used: QMiX, 17% EDTA, 10% citric acid (CA, 1% peracetic acid (PA, 2.5% NaOCl (solution control, and distilled water (negative control. The chelating solutions were used to irrigate the canal followed by 2.5% NaOCl as a final flush. After the irrigation protocols, all specimens were rinsed with 10 mL of distilled water to remove any residue of the chemical solutions. Before and after the final irrigation protocols, dentin microhardness was measured with a Knoop indenter. Three indentations were made at 100 µm and 500 µm from the root canal lumen. Afterwards, the specimens were prepared for scanning electron microscopic analysis and the amount of dentin erosion was examined. Wilcoxon and Kruskal-Wallis tests were used to analyze the results with a significance level set at 5%. At 100 µm, all protocols significantly reduced dentin microhardness (p < .05, while at 500 µm, this effect was detected only in the EDTA and QMiX groups (p < .05. CA was the irrigant that caused more extensive erosion in dentinal tubules, followed by PA and EDTA. QMiX opened dentinal tubules, but did not cause dentin erosion. Results suggest that QMiX and 17% EDTA reduced dentin microhardness at a greater depth. Additionally, QMiX did not cause dentin erosion.

  5. Joint optimization scheduling for water conservancy projects in complex river networks

    Directory of Open Access Journals (Sweden)

    Qin Liu

    2017-01-01

    Full Text Available In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi-period and multi-variable joint optimization scheduling model for flood control, drainage, and irrigation. In this model, the number of sluice holes, pump units, and hydropower station units to be opened were used as decision variables, and different optimization objectives and constraints were considered. This model was solved with improved genetic algorithms and verified using the Huaian Water Conservancy Project as an example. The results show that the use of the joint optimization scheduling led to a 10% increase in the power generation capacity and a 15% reduction in the total energy consumption. The change in the water level was reduced by 0.25 m upstream of the Yundong Sluice, and by 50% downstream of pumping stations No. 1, No. 2, and No. 4. It is clear that the joint optimization scheduling proposed in this study can effectively improve power generation capacity of the project, minimize operating costs and energy consumption, and enable more stable operation of various hydraulic structures. The results may provide references for the management of water conservancy projects in complex river networks.

  6. Effect of Irrigation Regimes on Yield of Two Commercial Varieties of Pomegranate in the Climatic Condition in Yazd

    Directory of Open Access Journals (Sweden)

    ali bafkar

    2017-02-01

    Full Text Available Introduction: The maximum water efficiency and water productivity of the agricultural sector is one of the most important and effective ways to deal with the water crisis and mitigate the effects of drought. Therefore, scientific and practical agricultural water productivity in terms of planning and development must be followed. Local or drip irrigation systems supply some of the moist around the roots and the plant uses the moisture in the soil. Irrigation systems and irrigation scheduling affect water uptake by plants. Matrials and Methods: In order to evaluate the effect of irrigation on the yield of 4-year-old pomegranate trees with local irrigation system (Bubbler in sandy loam soil with bulk density 1.15 grams per cubic centimeter a research was performed in Agriculture and Natural Resources Research Center of Yazd province with an altitude of 1230 meters . The region has an arid climate with 51 mm average annual rainfall and average annual temperature of 20 ° C, which is located 10 kilometers from the center of the city of Yazd. This project was designed in a factorial experiment with a randomized complete block with three irrigation regimes I1, I2, I3, including irrigation (FC100%, 25% of deficit irrigation (FC75% and 50 percent deficit irrigation (FC50% on two commercial cultivars of pomegranates, which have been growing at 3 × 4 with three replications. To prevent penetration of water per tree, plots adjacent to each block strip (three meters between rows and between plants within one and a half meters without irrigation tape were used as a guard. Trees around the pool shaped a rectangular building with a flow rate of 96 liters per hour for each tree using Bubbler system. The use of such a system with high flow rate, suitability and cost of such a system in orchards and vineyards, water supply reduces energy consumption in a tree in a short time. To prevent clogging of the filter, disc dropper was used at the beginning of the project

  7. Optimization of modern irrigation for biosaline agriculture

    International Nuclear Information System (INIS)

    Shahid, S.A.; Hasbini, B.

    2007-01-01

    Supplementation water is a must to offset the water requirement to produce profitable crops in most arid and semiarid zones, where fresh water resources are insufficient to meet the pressure of irrigated agriculture. This necessitates the use of poor quality water resources. These waters if not properly managed and used can cause serious soil related problems (salinity, sodicity, destruction of soil structure) in addition to decline in crop yields. Biosaline agriculture (using saline water on saline soils to grow salt-tolerant crops) becomes the only option for the farmer when both soil and water resources are saline and the water resource is scarce. In this regards key design considerations must be taken into account when irrigating with salty waters to optimize water uses and to reduce subsequent soil salinity development. Sprinkler irrigation systems are commonly used in irrigation of large-scale irrigational production systems. However they tend to concentrate salts on the leaves of plants. For this reason discharge and degree of overlap between consecutive sprinkler heads, are key design parameters when applying salty waters. Trickle irrigation is the most efficient system and is gaining importance in the GCC countries in the agriculture and landscape irrigation. The objective of this study was to optimize modern irrigation systems through development of design standards for drip (emitters spacing) and sprinkler irrigation systems (single head jet and overlapping) by applying saline water. The effect of emitter spacing (drip) and overlapping (sprinkler) were tested for the formation of salt contours in soil. The leaching ratio (LR) is the overall soil sanity within rhizosphere divided by the average irrigation water salinity. In this study LR is used to evaluate the effectiveness of irrigation systems in developing soil sanity. From the present investigations it is concluded that when using saline water for irrigation, the soil sanity development can be

  8. A model exploring whether the coupled effects of plant water supply and demand affect the interpretation of water potentials and irrigation management

    OpenAIRE

    Spinelli, GM; Shackel, KA; Gilbert, ME

    2017-01-01

    © 2017 Elsevier B.V. Water potential is a useful predictive tool in irrigation scheduling as it, or a component, is associated with physiological responses to water deficit. Increasing atmospheric demand for water increases transpiration and decreases water potential for the same stomatal conductance. However, based on supply by the soil-plant-atmosphere-continuum, decreasing soil water potential should decrease stomatal conductance and thus transpiration but also decrease water potential. Su...

  9. Converting Surface Irrigation to Pressurized Irrigation Systems and its Effecton Yield of OrangeTrees (Case Study:North of Khouzestan

    Directory of Open Access Journals (Sweden)

    M. Khorramian

    2017-01-01

    Full Text Available Introduction: North of the Khouzestan is one of the most important citrus production center. Usually border irrigation is used to irrigate citrus in this area. This system has generally low application efficiency. Several investigations in other arid region have demonstrated in addition to improved irrigation efficiency with low-volume pressurized irrigation systems, citrus trees have adapted with these new irrigation systems. However limited information exists on the performance of mature orchards converted from border surface irrigation to pressurized irrigation systems. Therefore, the current research was conducted to evaluate the feasibility of converting surface irrigation to pressurized irrigation systems on mature citrus trees in climate conditions of North Khouzestan. Materials and Methods: This study was conducted during three years at Safiabad Agricultural Research Center to evaluate the yield of citrus trees and the quality of fruits for two Marss and Valencia varieties which grow 7 years previously with surface irrigation and converted to pressurized irrigation systems. The treatments consisted of six irrigation methods including Overhead sprinkle irrigation (OHSI, Under tree sprinkle irrigation(UTSI, Trickle irrigation(TI(six 8 L/h Netafim emitters, Microjet irrigation (MI(two 180 microjet were located under canopy near of the trunk at opposite sides of trunk,Bubbler irrigation(BI(a single located under the canopy of each treeandSurface irrigation(SI method.Soil texture was clay loam well drained without salinity(ECe=0.69ds m-1, with 1.25 percent organic carbon. The experimental design was completely randomized design. The trees were irrigated during spring and summer seasons. For calculating irrigation water depth in TI, MI and BI systems, daily evaporation from a class A evaporation pan of the Safiabad weather station (nearby the experimental field was collected, and evapotranspiration of the citrus trees was calculated applying a

  10. GSM BASED IRRIGATION CONTROL AND MONITORING SYSTEM

    OpenAIRE

    GODFREY A. MILLS; STEPHEN K. ARMOO; AGYEMAN K. ROCKSON; ROBERT A. SOWAH; MOSES A. ACQUAH

    2013-01-01

    Irrigated agriculture is one of the primary water consumers in most parts of the world. With developments in technology, efforts are being channeled into automation of irrigation systems to facilitate remote control of the irrigation system and optimize crop production and cost effectiveness. This paper describes an on-going work on GSM based irrigation monitoring and control systems. The objective of the work is to provide an approach that helps farmers to easily access, manage and regulate ...

  11. Comparative efficiency of trickle and furrow irrigation

    International Nuclear Information System (INIS)

    Hanif, M.; Qureshi, R.H.; Sandhu, G.R.

    1976-01-01

    Comparison of furrow and trickle methods of irrigation to know their relative efficiency with respect to water applied and fertilizer used on tomatoes, cauliflower and lettuce as test crops using canal water, showed a significant saving of about 44 and 41 per cent respectively for irrigation water and fertilizer applied with trickle as compared to furrow irrigation. Trickle irrigated crops also showed a better response as regards the rate of survival, crop growth and time of maturity

  12. Mitigating global warming potentials of methane and nitrous oxide gases from rice paddies under different irrigation regimes.

    Science.gov (United States)

    Ali, Muhammad Aslam; Hoque, M Anamul; Kim, Pil Joo

    2013-04-01

    A field experiment was conducted in Bangladesh Agricultural University Farm to investigate the mitigating effects of soil amendments such as calcium carbide, calcium silicate, phosphogypsum, and biochar with urea fertilizer on global warming potentials (GWPs) of methane (CH4) and nitrous oxide (N2O) gases during rice cultivation under continuous and intermittent irrigations. Among the amendments phosphogypsum and silicate fertilizer, being potential source of electron acceptors, decreased maximum level of seasonal CH4 flux by 25-27 % and 32-38 % in continuous and intermittent irrigations, respectively. Biochar and calcium carbide amendments, acting as nitrification inhibitors, decreased N2O emissions by 36-40 % and 26-30 % under continuous and intermittent irrigations, respectively. The total GWP of CH4 and N2O gases were decreased by 7-27 % and 6-34 % with calcium carbide, phosphogypsum, and silicate fertilizer amendments under continuous and intermittent irrigations, respectively. However, biochar amendments increased overall GWP of CH4 and N2O gases.

  13. Energy performance of sprinkler irrigated maize, wheat and sunflower in Vigia irrigation district

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Sandra; Rodrigues, Goncalo Caleia; Paredes, Paula; Pereira, Luis S. [Centro de Engenharia dos Biossistemas (CEER/ISA), Lisboa (Portugal)], E-mail: lspereira@isa.utl.pt

    2008-07-01

    The energy potential of a crop may be evaluated through life cycle assessment methodologies. These refer to the computation of the crop's energy balance and other related indicators, such as the energy ratio and the energetic efficiency, that may be used as to assess how a given irrigated crop may be used for production of biofuel. This study concerns sprinkler irrigated sunflower, wheat and maize crops using data relative to the campaign of 2007 in the Vigia Irrigation District, Alentejo. A model was developed and various scenarios were considered. The modelling results lead to the conclusion that the maize crop is the most efficient in producing energy and sunflower is the least one for all the alternative scenarios considered. (author)

  14. Scenario Studies on Effects of Soil Infiltration Rates, Land Slope, and Furrow Irrigation Characteristics on Furrow Irrigation-Induced Erosion.

    Science.gov (United States)

    Dibal, Jibrin M; Ramalan, A A; Mudiare, O J; Igbadun, H E

    2014-01-01

    Furrow irrigation proceeds under several soil-water-furrow hydraulics interaction dynamics. The soil erosion consequences from such interactions in furrow irrigation in Samaru had remained uncertain. A furrow irrigation-induced erosion (FIIE) model was used to simulate the potential severity of soil erosion in irrigated furrows due to interactive effects of infiltration rates, land slope, and some furrow irrigation characteristics under different scenarios. The furrow irrigation characteristics considered were furrow lengths, widths, and stream sizes. The model itself was developed using the dimensional analysis approach. The scenarios studied were the interactive effects of furrow lengths, furrow widths, and slopes steepness; infiltration rates and furrow lengths; and stream sizes, furrow lengths, and slopes steepness on potential furrow irrigation-induced erosion, respectively. The severity of FIIE was found to relate somewhat linearly with slope and stream size, and inversely with furrow lengths and furrow width. The worst soil erosion (378.05 t/ha/yr) was found as a result of the interactive effects of 0.65 m furrow width, 50 m furrow length, and 0.25% slope steepness; and the least soil erosion (0.013 t/ha/yr) was induced by the combined effects of 0.5 l/s, 200 m furrow length, and 0.05% slope steepness. Evidently considering longer furrows in furrow irrigation designs would be a better alternative of averting excessive FIIE.

  15. Irrigation management in organic greenhouse

    NARCIS (Netherlands)

    Voogt, W.; Balendonck, J.; Berkelmans, R.; Enthoven, N.

    2017-01-01

    Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus

  16. Trash-polluted irrigation: characteristics and impact on agriculture

    Science.gov (United States)

    Sulaeman, D.; Arif, SS; Sudarmadji

    2018-04-01

    Trash pollution has been a problem in sustainable water resources management. Trash pollutes not only rivers, lakes and seas, but also irrigation canals and rice fields. This study aimed to identify the characteristics of solid waste (type, time of occurrence and sources of trash) and its impact on agriculture. The study was conducted in four irrigation areas, namely Gamping, Merdiko, Nglaren and Karangploso in Bantul District, Yogyakarta Special Region. We applied the Irrigation Rapid Trash Assessment (IRTA) as our field survey instrument. The results showed that trash was found throughout irrigation canals and rice fields, and the occurrence was influenced by water flow, time and farmer activities. The irrigation was dominantly polluted by plastic trash (52.2%), biodegradable waste (17.91%) and miscellaneous trash (12.3%). The IRTA score showed that Gamping Irrigation Area was at marginal condition, bearing a high risk of disturbing the operation and maintenance of the irrigation canals as well as farmers’ health. Trash in irrigation also generated technical impact of the irrigation operation and maintenance, environmental quality, and social life. This research also offered environmental policy integration approach and water-garbage governance approach as an alternative solution to manage water resources and agriculture in a sustainable manner, under the pressure of increasing amount of trash.

  17. [Optimal irrigation index for cotton drip irrigation under film mulching based on the evaporation from pan with constant water level].

    Science.gov (United States)

    Shen, Xiao-Jun; Zhang, Ji-Yang; Sun, Jing-Sheng; Gao, Yang; Li, Ming-Si; Liu, Hao; Yang, Gui-Sen

    2013-11-01

    A field experiment with two irrigation cycles and two irrigating water quotas at squaring stage and blossoming-boll forming stage was conducted in Urumqi of Xinjiang Autonomous Region, Northwest China in 2008-2009, aimed to explore the high-efficient irrigation index of cotton drip irrigation under film mulching. The effects of different water treatments on the seed yield, water consumption, and water use efficiency (WUE) of cotton were analyzed. In all treatments, there was a high correlation between the cotton water use and the evaporation from pan installed above the plant canopy. In high-yield cotton field (including the treatment T4 which had 10 days and 7 days of irrigation cycle with 30.0 mm and 37.5 mm of irrigating water quota at squaring stage and blossoming-boll forming stage, respectively in 2008, and the treatment T1 having 7 days of irrigation cycle with 22.5 mm and 37.5 mm of irrigating water quota at squaring stage and blossoming-boll forming stage, respectively in 2009), the pan-crop coefficient (Kp) at seedling stage, squaring stage, blossoming-boll forming stage, and boll opening stage was 0.29-0.30, 0.52-0.53, 0.74-0.88, and 0.19-0.20, respectively. As compared with the other treatments, T4 had the highest seed cotton yield (5060 kg x hm(-2)) and the highest WUE (1.00 kg x m(-3)) in 2008, whereas T1 had the highest seed cotton yield (4467 kg x hm(-2)) and the highest WUE (0.99 kg x m(-3)) in 2009. The averaged cumulative pan evaporation in 7 days and 10 days at squaring stage was 40-50 mm and 60-70 mm, respectively, and that in 7 days at blossoming-boll forming stage was 40-50 mm. It was suggested that in Xinjiang cotton area, irrigating 45 mm water for seedling emergence, no irrigation both at seedling stage and at boll opening stage, and irrigation was started when the pan evaporation reached 45-65 mm and 45 mm at squaring stage and blossoming-boll stage, respectively, the irrigating water quota could be determined by multiplying cumulative

  18. Correlation Coefficient, Path Analysis and Drought Tolerance Indices for Different Wheat Cultivars under Deficit Irrigation Conditions of Isfahan Region

    Directory of Open Access Journals (Sweden)

    H. R Salemi

    2017-06-01

    controlled, following the recommendations given by Isfahan Pest Management Department. At harvest, the final total grain yield per plot was determined. The amount of evapotranspiration for irrigation scheduling was determined by using a crop coefficient (KC, ETpan from measured daily open Class A pan evaporation data, and pan coefficient values from FAO 24 (Doorenbos & Pruitt, 1977. Irrigation water requirement was calculated as the difference between ETc (=KC times ET0 and the effective rainfall amount. In this study, pan evaporation and rainfall amount data collected from the Kabutar Abad meteorological station located at the agricultural research center were used for calculating irrigation water application quantities. The irrigation schedule was timed to meet the crop water requirement. The depth of irrigation water and consequently the volume of water were applied weekly and irrigation amounts equaled the previous week’s evapotranspiration (ETc from the crop. Then, taking into consideration the discharge of the irrigation siphons, the relevant irrigation duration for each treatment was also determined. For path analysis and determining direct and indirect effects of yield components on grain yield, three years data were used (3 Irr * 6 cultivars * 3 years. Results and Discussion Results showed significant correlations of grain yield with: productivity degree (r=0.798**, spike number per m2 (r=0.71**, biological yield (r=0.629**, harvest index (r=0.538**, and plant height (r=0.284*, respectively, and there was not significant correlation between grain yield with water use efficiency, straw yield, TGW and grain number per spike. On based of indices of drought tolerance (Tolerance Index=TOL, Mean Productivity=MP, Geometric Mean Productivity=GMP, Stress Susceptibility Index=STI and Harmonic Mean=HM, %60 of full irrigation for Pishtaz wheat cultivar was substantially increased water productivity (WP. Amounts of TOL, MP, GMP, STI, HM and WP for Pishtaz cultivar were -0

  19. performance evaluation of sprinkler irrigation system at mambilla

    African Journals Online (AJOL)

    HOD

    ratio (DPR), irrigation productivity (IP), labour requirements and water quality. Standard procedure was ... The exchangeable cations analysis of Kakara irrigation ... Keywords: Tea, irrigation System, Performance Evaluation. 1. INTRODUCTION.

  20. Expanding the Annual Irrigation Maps (AIM) Product to the entire High Plains Aquifer (HPA): Addressing the Challenges of Cotton and Deficit-Irrigated Fields

    Science.gov (United States)

    Rapp, J. R.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.

    2017-12-01

    The High Plains Aquifer (HPA) is the most extensively irrigated aquifer in the continental United States and is the largest major aquifer in North America with an area of 500,000 km2. Increased demand for agricultural products has led to expanded irrigation extent, but brought with it declining groundwater levels that have made irrigation unsustainable in some locations. Understanding these irrigation dynamics and mapping irrigated areas through time are essential for future sustainable agricultural practices and hydrological modeling. Map products using remote sensing have only recently been able to track annual dynamics at relatively high spatial resolution (30 m) for a large portion of the northern HPA. However follow-on efforts to expand these maps to the entire HPA have met with difficulty due to the challenge of distinguishing irrigation in crop types that are commonly deficit- or partially-irrigated. Expanding these maps to the full HPA requires addressing unique features of partially irrigated fields and irrigated cotton, a major water user in the southern HPA. Working in Google Earth Engine, we used all available Landsat imagery to generate annual time series of vegetation indices. We combined this information with climate covariables, planting dates, and crop specific training data to algorithmically separate fully irrigated, partially irrigated, and non-irrigated field locations. The classification scheme was then applied to produce annual maps of irrigation across the entire HPA. The extensive use of ancillary data and the "greenness" time series for the algorithmic classification generally increased accuracy relative to previous efforts. High-accuracy, representative map products of irrigation extent capable of detecting crop type and irrigation intensity within aquifers will be an essential tool to monitor the sustainability of global aquifers and to provide a scientific bases for political and economic decisions affecting those aquifers.

  1. Managing Water Resources for Environmentally Sustainable Irrigated Agriculture in Pakistan

    OpenAIRE

    Muhammad Afzal

    1996-01-01

    Pakistan’s agriculture is almost wholly dependent on irrigation and irrigated land supplies more than 90 percent of agricultural production. Irrigation is central to Pakistan’s economy. Massive investments in irrigation contributed to the development of one of the largest Indus Basin Irrigation System. Despite heavy budgetary inputs in irrigation system, it is facing shortage of resources and suffering from operational problems. The sustainability of irrigated agriculture is threatened due to...

  2. An improved delivery system for bladder irrigation.

    Science.gov (United States)

    Moslemi, Mohammad K; Rajaei, Mojtaba

    2010-10-05

    Occasionally, urologists may see patients requiring temporary bladder irrigation at hospitals without stocks of specialist irrigation apparatus. One option is to transfer the patient to a urology ward, but often there are outstanding medical issues that require continued specialist input. Here, we describe an improved system for delivering temporary bladder irrigation by utilizing readily available components and the novel modification of a sphygmomanometer blub. This option is good for bladder irrigation in patients with moderate or severe gross hematuria due to various causes. In this prospective study from March 2007 to April 2009, we used our new system in eligible cases. In this system, an irrigant bag with 1 L of normal saline was suspended 80 cm above the indwelled 3-way Foley catheter, and its drainage tube was inserted into the irrigant port of the catheter. To increase the flow rate of the irrigant system, we inserted a traditional sphygmomanometer bulb at the top of the irrigant bag. This closed system was used for continuous bladder irrigation (CBI) in patients who underwent open prostatectomy, transurethral resection of the prostate (TURP), or transurethral resection of the bladder (TURB). This high-pressure system is also used for irrigation during cystourethroscopy, internal urethrotomy, and transurethral lithotripsy. Our 831 eligible cases were divided into two groups: group 1 were endourologic cases and group 2 were open prostatectomy, TURP, and TURB cases. The maximum and average flow rates were evaluated. The efficacy of our new system was compared prospectively with the previous traditional system used in 545 cases. In group 1, we had clear vision at the time of endourologic procedures. The success rate of this system was 99.5%. In group 2, the incidence of clot retention decreased two fold in comparison to traditional gravity-dependent bladder flow system. These changes were statistically significant (P = 0.001). We did not observe any adverse

  3. Review of root canal irrigant delivery techniques and devices

    Directory of Open Access Journals (Sweden)

    Yeon-Jee Yoo

    2011-05-01

    Full Text Available Introduction Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.

  4. Size and stochasticity in irrigated social-ecological systems

    Science.gov (United States)

    Puy, Arnald; Muneepeerakul, Rachata; Balbo, Andrea L.

    2017-03-01

    This paper presents a systematic study of the relation between the size of irrigation systems and the management of uncertainty. We specifically focus on studying, through a stylized theoretical model, how stochasticity in water availability and taxation interacts with the stochastic behavior of the population within irrigation systems. Our results indicate the existence of two key population thresholds for the sustainability of any irrigation system: or the critical population size required to keep the irrigation system operative, and N* or the population threshold at which the incentive to work inside the irrigation system equals the incentives to work elsewhere. Crossing irretrievably leads to system collapse. N* is the population level with a sub-optimal per capita payoff towards which irrigation systems tend to gravitate. When subjected to strong stochasticity in water availability or taxation, irrigation systems might suffer sharp population drops and irreversibly disintegrate into a system collapse, via a mechanism we dub ‘collapse trap’. Our conceptual study establishes the basis for further work aiming at appraising the dynamics between size and stochasticity in irrigation systems, whose understanding is key for devising mitigation and adaptation measures to ensure their sustainability in the face of increasing and inevitable uncertainty.

  5. Assessing the Efficacy of the SWAT Auto-Irrigation Function to Simulate Irrigation, Evapotranspiration, and Crop Response to Management Strategies of the Texas High Plains

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2017-07-01

    Full Text Available In the semi-arid Texas High Plains, the underlying Ogallala Aquifer is experiencing continuing decline due to long-term pumping for irrigation with limited recharge. Accurate simulation of irrigation and other associated water balance components are critical for meaningful evaluation of the effects of irrigation management strategies. Modelers often employ auto-irrigation functions within models such as the Soil and Water Assessment Tool (SWAT. However, some studies have raised concerns as to whether the function is able to adequately simulate representative irrigation practices. In this study, observations of climate, irrigation, evapotranspiration (ET, leaf area index (LAI, and crop yield derived from an irrigated lysimeter field at the USDA-ARS Conservation and Production Research Laboratory at Bushland, Texas were used to evaluate the efficacy of the SWAT auto-irrigation functions. Results indicated good agreement between simulated and observed daily ET during both model calibration (2001–2005 and validation (2006–2010 periods for the baseline scenario (Nash-Sutcliffe efficiency; NSE ≥ 0.80. The auto-irrigation scenarios resulted in reasonable ET simulations under all the thresholds of soil water deficit (SWD triggers as indicated by NSE values > 0.5. However, the auto-irrigation function did not adequately represent field practices, due to the continuation of irrigation after crop maturity and excessive irrigation when SWD triggers were less than the static irrigation amount.

  6. Evaluation of apical extrusion of debris and irrigant using two new reciprocating and one continuous rotation single file systems.

    Science.gov (United States)

    Nayak, Gurudutt; Singh, Inderpreet; Shetty, Shashit; Dahiya, Surya

    2014-05-01

    Apical extrusion of debris and irrigants during cleaning and shaping of the root canal is one of the main causes of periapical inflammation and postoperative flare-ups. The purpose of this study was to quantitatively measure the amount of debris and irrigants extruded apically in single rooted canals using two reciprocating and one rotary single file nickel-titanium instrumentation systems. Sixty human mandibular premolars, randomly assigned to three groups (n = 20) were instrumented using two reciprocating (Reciproc and Wave One) and one rotary (One Shape) single-file nickel-titanium systems. Bidistilled water was used as irrigant with traditional needle irrigation delivery system. Eppendorf tubes were used as test apparatus for collection of debris and irrigant. The volume of extruded irrigant was collected and quantified via 0.1-mL increment measure supplied on the disposable plastic insulin syringe. The liquid inside the tubes was dried and the mean weight of debris was assessed using an electronic microbalance. The data were statistically analysed using Kruskal-Wallis nonparametric test and Mann Whitney U test with Bonferroni adjustment. P-values less than 0.05 were considered significant. The Reciproc file system produced significantly more debris compared with OneShape file system (P0.05). Extrusion of irrigant was statistically insignificant irrespective of the instrument or instrumentation technique used (P >0.05). Although all systems caused apical extrusion of debris and irrigant, continuous rotary instrumentation was associated with less extrusion as compared with the use of reciprocating file systems.

  7. Sensing technologies for precision irrigation

    CERN Document Server

    Ćulibrk, Dubravko; Minic, Vladan; Alonso Fernandez, Marta; Alvarez Osuna, Javier; Crnojevic, Vladimir

    2014-01-01

    This brief provides an overview of state-of-the-art sensing technologies relevant to the problem of precision irrigation, an emerging field within the domain of precision agriculture. Applications of wireless sensor networks, satellite data and geographic information systems in the domain are covered. This brief presents the basic concepts of the technologies and emphasizes the practical aspects that enable the implementation of intelligent irrigation systems. The authors target a broad audience interested in this theme and organize the content in five chapters, each concerned with a specific technology needed to address the problem of optimal crop irrigation. Professionals and researchers will find the text a thorough survey with practical applications.

  8. Intervention processes and irrigation institutions : sustainability of farmer managed irrigation systems in Nepal

    OpenAIRE

    Pant, D.R.

    2000-01-01

    With the support from various donors, His Majesty's Government of Nepal has implemented support programmes with a view to transform water availability, improve production, and increase the institutional capabilities of farmers to develop and sustain efficient, fair and reliable irrigation management practices in irrigation systems in Nepal. In this respect, this study aimed to understand the social, administrative and political processes involved in the social and institutional chang...

  9. Constraint-based job shop scheduling with ILOG SCHEDULER

    NARCIS (Netherlands)

    Nuijten, W.P.M.; Le Pape, C.

    1998-01-01

    We introduce constraint-based scheduling and discuss its main principles. An approximation algorithm based on tree search is developed for the job shop scheduling problem using ILOG SCHEDULER. A new way of calculating lower bounds on the makespan of the job shop scheduling problem is presented and

  10. Irrigation and avifaunal change in coastal Northwest Mexico: has irrigated habit attracted threatened migratory species?

    Science.gov (United States)

    Grason, Emily; Navarro-Sigüenza, Adolfo G.

    2015-01-01

    Irrigation in desert ecosystems can either reduce or increase species diversity. Groundwater pumping often lowers water tables and reduces natural wetlands, whereas canal irrigation often creates mesic habitat, resulting in great increases in avian diversity from irrigation. Here we compare a dataset of potential natural vegetation to recent datasets from areal and satellite imagery to show that 60% of the land in the coastal plain of southern Sonora and northern Sinaloa lying below 200 m elevation has been converted by irrigation to more mesic habitats. We then use the record of bird specimens in the world’s museums from this same region of Mexico to examine the avian community before and after the development of extensive irrigation. In general these museum records show an increase in the abundance and diversity of breeding birds associated with mesic habitats. Although thorn forest birds have likely decreased in total numbers, most are common enough in the remaining thorn forest that collection records did not indicate their probable decline. Four migrants having most of their breeding ranges in the US or Canada, Yellow-billed Cuckoo, Cliff Swallow, Bell’s Vireo, and Orchard Oriole, apparently have increased dramatically as breeders in irrigated habitats of NW Mexico. Because these species have decreased or even largely disappeared as breeding birds in parts of the US or Canada, further research should assess whether their increases in new mesic habitats of NW Mexico are linked to their declines as breeding birds in Canada and the US For Bell’s Vireo recent specimens from Sinaloa suggest its new breeding population in NW Mexico may be composed partly of the endangered Least Bell’s Vireo. PMID:26312181

  11. ASPECTS OF DRIP IRRIGATION ON SLOPES

    Directory of Open Access Journals (Sweden)

    Oprea Radu

    2010-01-01

    Full Text Available Nowadays, water and its supply raise problems of strategic importance, of great complexity, being considered one of the keys to sustainable human development. Drip irrigation consists in the slow and controlled administration of water in the area of the root system of the plants for the purposes of fulfilling their physiological needs and is considered to be one of the variants of localized irrigation. Water is distributed in a uniform and slow manner, drop by drop, in a quantity and with a frequency that depend on the needs of the plant, thanks to the exact regulation of the water flow rate and pressure, as well as to the activation of the irrigation based on the information recorded by the tensiometer with regard to soil humidity. This method enables the exact dosage of the water quantity necessary in the various evolution stages of the plant, thus eliminating losses. By applying the irrigation with 5 liters of water per linear meter, at a 7 days interval, in the month of august, for a vine cultivated on a slope, in layers covered with black film and irrigated via dropping, soil humidity immediately after irrigation reaches its highest level, but within the limits of active humidity, on the line of the irrigation band. Three days later, the water content of the soil in the layer is relatively uniform, and, after this interval, it is higher in the points situated at the basis of the film. This technology of cultivation on slopes favors the accumulation, in the soil, of the water resulted from heavy rains and reduces soil losses as a result of erosion.

  12. improving of irrigation management: a learning based approach

    African Journals Online (AJOL)

    p2333147

    Irrigation farms are small businesses and like any other business, the managers or ... human factors and constraints that impact on the adoption of irrigation ... Informal interaction with other irrigation farmers and social networks played a ...

  13. Saline water irrigation for crop production

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A R [Directorate of Water Management Research, Indian Council of Agricultural Research (ICAR), Walmi Complex, P.O. - Phulwari Sharif, Patna (India); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Singh, S S; Singh, S R [Directorate of Water Management Research, Indian Council of Agricultural Research (ICAR), Walmi Complex, P.O. - Phulwari Sharif, Patna (India)

    2001-05-01

    Salinity is one of agriculture's most complex production problems. Excessive salts from irrigation water or high water tables can severely limit crop production. Years of saline water irrigation on poorly drained soils can eventually make economic crop production impossible. About 10% of all land are affected by salinity problems. They occur in every continent in different proportions, more frequently in arid and semi-arid areas. This paper discusses a range of problems related to use of saline water for crop irrigation.

  14. Saline water irrigation for crop production

    International Nuclear Information System (INIS)

    Khan, A.R.; Singh, S.S.; Singh, S.R.

    2001-05-01

    Salinity is one of agriculture's most complex production problems. Excessive salts from irrigation water or high water tables can severely limit crop production. Years of saline water irrigation on poorly drained soils can eventually make economic crop production impossible. About 10% of all land are affected by salinity problems. They occur in every continent in different proportions, more frequently in arid and semi-arid areas. This paper discusses a range of problems related to use of saline water for crop irrigation

  15. Evaluation of the Effect of Different Irrigation Levels of Drip Irrigation (Tape on Yield and Yield Components of Corn

    Directory of Open Access Journals (Sweden)

    mohammad karimi

    2016-02-01

    Full Text Available Introduction: One of the serious problems in the further development of maize cultivation is increasing irrigation efficiency. Using conventional irrigation causes a shortage of water resources to increase the acreage of the crop. With regard to the development of maize cultivation, agronomic and executable methods must be studied to reduce water consumption. Using drip irrigation system is most suitable for row crops. Hamedi et al. (2005 compared drip (tape and surface irrigation systems on yield of maize in different levels of water requirement and indicated that drip irrigation increases the amount of yield to 2015 kg/ha and water use efficiency to 3 time. Kohi et al. (2005 investigated the effects of deficit irrigation use of drip (tape irrigation on water use efficiency on maize in planting of one and two rows. The results showed that maximum water use efficiency related to crop density, water requirement and planting pattern 85000, 125% and two rows, respectively with 1.46 kg/m3. Jafari and Ashrafi (2011 studied the effects of irrigation levels, plant density and planting pattern in drip irrigation (tape on corn. The results showed that the amount of irrigation water and crop density on the level of 1% and their interactions and method of planting were significant at the 5 and 10% on water use efficiency, respectively. The yield was measured under different levels of irrigation, crop density and method of planting and the difference was significant on the level of 1%. Lamm et al. (1995 studied water requirement of maize in field with silt loam texture under sub drip irrigation and reported that water use reduced to 75%; but yield of maize remained at maximum amount of 12.5 t/ha. The objective of this study was to evaluate the drip (tape irrigation method for corn production practices in the Qazvin province in Iran. Materials and Methods: In this study, yield and yield components of corn (SC 704 were investigated under different levels of

  16. Introduction: Panda or Hydra? The untold stories of drip irrigation

    NARCIS (Netherlands)

    Kuper, M.; Venot, J.P.; Zwarteveen, M.; Venot, J.P.; Kuper, M.; Zwarteveen, M.

    2017-01-01

    Irrigated areas in the world are witnessing a transformation from open canal systems to more ‘modern’ irrigation methods such as drip irrigation that convey water through closed pipe systems. Initially associated with hi-tech irrigated agriculture, drip irrigation is now being used by a wide range

  17. [Ecological risks of reclaimed water irrigation: a review].

    Science.gov (United States)

    Chen, Wei-Ping; Zhang, Wei-Ling; Pan, Neng; Jiao, Wen-Tao

    2012-12-01

    Wastewater reclamation and reuse have become an important approach to alleviate the water crisis in China because of its social, economic and ecological benefits. The irrigation on urban green space and farmland is the primary utilization of reclaimed water, which has been practiced world widely. To understand the risk of reclaimed water irrigation, we summarized and reviewed the publications associated with typical pollutants in reclaimed water including salts, nitrogen, heavy metals, emerging pollutants and pathogens, systematically analyzed the ecological risk posed by reclaimed water irrigation regarding plant growth, groundwater quality and public health. Studies showed that salt and salt ions were the major risk sources of reclaimed water irrigation, spreading disease was another potential risk of using reclaimed water, and emerging pollutants was the hot topic in researches of ecological risk. Based on overseas experiences, risk control measures on reclaimed water irrigation in urban green space and farmland were proposed. Five recommendations were given to promote the safe use of reclaimed water irrigation including (1) strengthen long-term in situ monitoring, (2) promote the modeling studies, (3) build up the connections of reclaimed water quality, irrigation management and ecological risk, (4) evaluate the soil bearing capacity of reclaimed water irrigation, (5) and establish risk management system of reclaimed water reuse.

  18. Ocean-Atmosphere Interactions Modulate Irrigation's Climate Impacts

    Science.gov (United States)

    Krakauer, Nir Y.; Puma, Michael J.; Cook, Benjamin I.; Gentine, Pierre; Nazarenko, Larissa

    2016-01-01

    Numerous studies have focused on the local and regional climate effects of irrigated agriculture and other land cover and land use change (LCLUC) phenomena, but there are few studies on the role of ocean- atmosphere interaction in modulating irrigation climate impacts. Here, we compare simulations with and without interactive sea surface temperatures of the equilibrium effect on climate of contemporary (year 2000) irrigation geographic extent and intensity. We find that ocean-atmosphere interaction does impact the magnitude of global-mean and spatially varying climate impacts, greatly increasing their global reach. Local climate effects in the irrigated regions remain broadly similar, while non-local effects, particularly over the oceans, tend to be larger. The interaction amplifies irrigation-driven standing wave patterns in the tropics and mid-latitudes in our simulations, approximately doubling the global-mean amplitude of surface temperature changes due to irrigation. The fractions of global area experiencing significant annual-mean surface air temperature and precipitation change also approximately double with ocean-atmosphere interaction. Subject to confirmation with other models, these findings imply that LCLUC is an important contributor to climate change even in remote areas such as the Southern Ocean, and that attribution studies should include interactive oceans and need to consider LCLUC, including irrigation, as a truly global forcing that affects climate and the water cycle over ocean as well as land areas.

  19. Mapping Irrigation Potential in the Upper East Region of Ghana

    Science.gov (United States)

    Akomeah, E.; Odai, S. N.; Annor, F. O.; Adjei, K. A.; Barry, B.

    2009-04-01

    The Upper East Region together with the other two regions in Northern Ghana (Upper West and Northern Region) is seen as the locus of perennial food deficit (GPRS, 2003). Despite, the provision of over 200 small scale dams and various mechanisms aimed at poverty alleviation, the region is still plagued with poverty and yearly food shortages. To achieve food security and alleviate poverty in the region however, modernization of agriculture through irrigation is deemed inevitable. While it is true that considerable potential still exists for future expansion of irrigation, it cannot be refuted that water is becoming scarcer in the regions where the need for irrigation is most important, hence mapping the irrigation potential of the region will be the first step toward ensuring sound planning and sustainability of the irrigation developments. In this study, an attempt has been made to map out the irrigation potential of the Upper East Region. The river basin approach was used in assessing the irrigation potential. The catchments drained by The White Volta river, Red volta river, River Sissili and River Kulpawn were considered in the assessment. The irrigation potential for the sub basins was computed by combining information on gross irrigation water requirements for the selected cash crops, area of soil suitable for irrigation and available water resources. The capacity of 80%, 70%, 60% and 50% time of exceedance flow of the available surface water resources in the respective sub basins was estimated. The area that can be irrigated with this flow was computed with selected cropping pattern. Combining the results of the potential irrigable areas and the land use map of the respective sub basins, an irrigation potential map has been generated showing potential sites in the upper east region that can be brought under irrigation. Keywords: Irrigation potential, irrigation water requirement, land evaluation, dependable flow

  20. Irrigation ponds: Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    DONG Bin; MAO Zhi; BROWN Larry; CHEN XiuHong; PENG LiYuan; WANG JianZhang

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and un-recycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China.With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious.Traditional ir-rigation and drainage systems only focus on issues concerning water quantity, i.e.the capacity of irri-gation in drought and drainage in waterlogging period, yet have no requirement on water quality im-provement, how to clean the water quality of farmland drainage through remodeling the existing irriga-tion and drainage systems has a very important realistic meaning.Pond is an important irrigation facil-ity in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use.Such water storage features of pond provide the possibility and potential capacity for drainage water treat-ment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system.To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site.The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water.Other issues, e.g.how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  1. Irrigation ponds:Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    BROWN; Larry

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  2. Sustainable irrigation in fruit trees

    Directory of Open Access Journals (Sweden)

    Cristos Xiloyannis

    2010-09-01

    Full Text Available Water management in fruit growing, particularly in areas with high water deficit, low rainfall and limited availability of water for irrigation should aid to save water by: i the choice of high efficiency irrigation methods and their correct management; ii the proper choice of the specie, cultivar and rootstock to optimise plant water use; iii the proper choice of the architecture of the canopy and it’s correct management in order to improve water use efficiency; iv the application of regulated deficit irrigation at growth stages less sensitive to water deficit; v strengthening the role of technical assistance for a rapid transfer of knowledge to the growers on the sustainable use of water in fruit growing.

  3. Sustainable irrigation in fruit trees

    Directory of Open Access Journals (Sweden)

    Cristos Xiloyannis

    Full Text Available Water management in fruit growing, particularly in areas with high water deficit, low rainfall and limited availability of water for irrigation should aid to save water by: i the choice of high efficiency irrigation methods and their correct management; ii the proper choice of the specie, cultivar and rootstock to optimise plant water use; iii the proper choice of the architecture of the canopy and it’s correct management in order to improve water use efficiency; iv the application of regulated deficit irrigation at growth stages less sensitive to water deficit; v strengthening the role of technical assistance for a rapid transfer of knowledge to the growers on the sustainable use of water in fruit growing.

  4. Irrigation Water Management in Latin America Manejo del Agua de Riego en Sudamérica

    Directory of Open Access Journals (Sweden)

    Aureo S de Oliveira

    2009-12-01

    Full Text Available Latin American countries show a great potential for expanding their irrigated areas. Irrigation is important for strengthening local and regional economy and for enhancing food security. The present paper aimed at providing a brief review on key aspects of irrigation management in Latin America. Poor irrigation management can have great impact on crop production and on environment while good management reduces the waste of soil and water and help farmers maximizing their profits. It was found that additional research is needed to allow a better understanding of crop water requirements under Latin American conditions as well as to provide farmers with local derived information for irrigation scheduling. The advantages of deficit irrigation practices and the present and future opportunities with the application of remote sensing tools for water management were also considered. It is clear that due to the importance of irrigated agriculture, collaborative work among Latin American researchers and institutions is of paramount importance to face the challenges imposed by a growing population, environment degradation, and competition in the global market.Los países sudamericanos tienen un gran potencial para aumentar sus áreas regadas. El riego es importante para fortalecer las economías locales y regionales y para mejorar la seguridad alimentaria. Esta revisión tiene por objeto proporcionar un resumen de los aspectos más importantes del manejo del riego en Sudamérica. Un manejo pobre del riego puede tener un alto impacto en la producción de cultivos y en el ambiente, en tanto que un buen manejo reduce las pérdidas de suelo y agua, y ayuda a los productores a maximizar sus ingresos. Se encontró que se requiere investigación adicional que permita una mejor comprensión de los requerimientos de agua de los cultivos en las condiciones sudamericanas, y también para proporcionar a los agricultores información local que permita hacer programaci

  5. Rice Photosynthetic Productivity and PSII Photochemistry under Nonflooded Irrigation

    Directory of Open Access Journals (Sweden)

    Haibing He

    2014-01-01

    Full Text Available Nonflooded irrigation is an important water-saving rice cultivation technology, but little is known on its photosynthetic mechanism. The aims of this work were to investigate photosynthetic characteristics of rice during grain filling stage under three nonflooded irrigation treatments: furrow irrigation with plastic mulching (FIM, furrow irrigation with nonmulching (FIN, and drip irrigation with plastic mulching (DI. Compared with the conventional flooding (CF treatment, those grown in the nonflooded irrigation treatments showed lower net photosynthetic rate (PN, lower maximum quantum yield (Fv/Fm, and lower effective quantum yield of PSII photochemistry (ΦPSII. And the poor photosynthetic characteristics in the nonflooded irrigation treatments were mainly attributed to the low total nitrogen content (TNC. Under non-flooded irrigation, the PN, Fv/Fm, and ΦPSII significantly decreased with a reduction in the soil water potential, but these parameters were rapidly recovered in the DI and FIM treatments when supplementary irrigation was applied. Moreover, The DI treatment always had higher photosynthetic productivity than the FIM and FIN treatments. Grain yield, matter translocation, and dry matter post-anthesis (DMPA were the highest in the CF treatment, followed by the DI, FIM, and FIN treatments in turn. In conclusion, increasing nitrogen content in leaf of rice plants could be a key factor to improve photosynthetic capacity in nonflooded irrigation.

  6. Irrigation Capability Evaluation of Illushi Floodplain, Edo State, Nigeria

    Directory of Open Access Journals (Sweden)

    A.S. Umweni

    2014-06-01

    Full Text Available Many irrigation projects, especially in the developing tropical regions, are embarked upon without any land capability assessment, resulting in avoidable and undesirable ecological consequences. The aim of this study is to assess the irrigation capability potentials of the soils of a rice growing Illushi/Ega community in Edo State of Nigeria. Soils of Illushi/Ega (200 ha were studied to establish their irrigation capabilities. Water samples were collected from the rivers within and near the sites at the proposed points of intake structures and analyzed for salinity (ECw, permeability (SAR and ion toxicity [Chlorine (Cl and Boron (B]. Gravity irrigation suitability assessment was carried out following the guidelines of the United States Bureau for Land Reclamation (USBR, 1953 and FAO (1979. Results showed that about 5.5 % of the land was non-irrigable, 11.5 % was marginally irrigable, 30.5% was moderately irrigable and 52.5 % highly irrigable.Thus about 83 % of the total land area was found to be irrigable. The results of analyses of irrigation water [ECw, SAR and Cl and B (ion toxicity problems in water sources were 0.1 – 0.7 dS m-1, 1.2 – 1.7, 0.6 – 1.8 cmol kg-1 and 0.5 – 0.7 mg kg-1] also show that there is no indication of salinity or ion toxicity problem.

  7. Grower demand for sensor-controlled irrigation

    Science.gov (United States)

    Lichtenberg, Erik; Majsztrik, John; Saavoss, Monica

    2015-01-01

    Water scarcity is likely to increase in the coming years, making improvements in irrigation efficiency increasingly important. An emerging technology that promises to increase irrigation efficiency substantially is a wireless irrigation sensor network that uploads sensor data into irrigation management software, creating an integrated system that allows real-time monitoring and control of moisture status that has been shown in experimental settings to reduce irrigation costs, lower plant loss rates, shorten production times, decrease pesticide application, and increase yield, quality, and profit. We use an original survey to investigate likely initial acceptance, ceiling adoption rates, and profitability of this new sensor network technology in the nursery and greenhouse industry. We find that adoption rates for a base system and demand for expansion components are decreasing in price, as expected. The price elasticity of the probability of adoption suggests that sensor networks are likely to diffuse at a rate somewhat greater than that of drip irrigation. Adoption rates for a base system and demand for expansion components are increasing in specialization in ornamental production: growers earning greater shares of revenue from greenhouse and nursery operations are willing to pay more for a base system and are willing to purchase larger numbers of expansion components at any given price. We estimate that growers who are willing to purchase a sensor network expect investment in this technology to generate significant profit, consistent with findings from experimental studies.

  8. Safe and High Quality Food Production using Low Quality Waters and Improved Irrigation Systems and Management (SAFIR)

    Science.gov (United States)

    Cary, L.; Kloppmann, W.; Battilani, A.; Bertaki, M.; Blagojevic, S.; Chartzoulakis, K.; Dalsgaard, A.; Forslund, A.; Jovanovic, Z.; Kasapakis, I.

    2009-04-01

    allows comparing different combinations of (1) water quality, including tap water as a reference, (2) irrigation techniques, and (3) irrigation strategies (including full irrigation, partial root drying, RDI). The replication of each of the combinations on three different plots takes into account the local variations of soil properties and allows a proper statistical treatment. Reactions of the infiltrating water with the soil solid phase are important for the solute cycling, temporary fixation and remobilisation of trace pollutants. The type of reaction (sorption, co-precipitation…) and the reactive mineral phases will also determine the availability of trace elements for the plant and determine the passage towards crops and products. Therefore it is important to assess the soil water quality, directly or indirectly. Direct measurements of soil water imply soil water sampling through an appropriate system; porous cups were installed on the Cretan, Italian and Chinese sites. Indirect evaluation of water-soil interactions can be obtained through sequential extractions. The combination of a variable input function (through diffuse pollution, irrigation, fertigation) and of variable MTE mobility in soils can be expected to lead to short term variations in soil metal concentrations even if such short term variations have been rarely investigated (Féder, 2001; Cary and Trolard, 2008). The sampling focused upon the fully irrigated plots given that the potential impact of irrigation water quality on soil and plant quality can be expected higher for fully irrigated soils compared to other irrigation strategies. Samples were taken within the soil volume of potential influence around each of the drip emitters. This volume varies depending on the nature of the soil and the irrigation system so that each site adopted a specific protocol. For all experiments, three sampling campaigns were scheduled for each irrigation season: at pre-planting, at the end of irrigation, at harvest

  9. Evaluation of apical extrusion of debris and irrigant using two new reciprocating and one continuous rotation single file systems.

    Directory of Open Access Journals (Sweden)

    Gurudutt Nayak

    2014-06-01

    Full Text Available Apical extrusion of debris and irrigants during cleaning and shaping of the root canal is one of the main causes of periapical inflammation and postoperative flare-ups. The purpose of this study was to quantitatively measure the amount of debris and irrigants extruded apically in single rooted canals using two reciprocating and one rotary single file nickel-titanium instrumentation systems.Sixty human mandibular premolars, randomly assigned to three groups (n = 20 were instrumented using two reciprocating (Reciproc and Wave One and one rotary (One Shape single-file nickel-titanium systems. Bidistilled water was used as irrigant with traditional needle irrigation delivery system. Eppendorf tubes were used as test apparatus for collection of debris and irrigant. The volume of extruded irrigant was collected and quantified via 0.1-mL increment measure supplied on the disposable plastic insulin syringe. The liquid inside the tubes was dried and the mean weight of debris was assessed using an electronic microbalance. The data were statistically analysed using Kruskal-Wallis nonparametric test and Mann Whitney U test with Bonferroni adjustment. P-values less than 0.05 were considered significant.The Reciproc file system produced significantly more debris compared with OneShape file system (P0.05. Extrusion of irrigant was statistically insignificant irrespective of the instrument or instrumentation technique used (P >0.05.Although all systems caused apical extrusion of debris and irrigant, continuous rotary instrumentation was associated with less extrusion as compared with the use of reciprocating file systems.

  10. Refinery scheduling

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Marcus V.; Fraga, Eder T. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Shah, Nilay [Imperial College, London (United Kingdom)

    2004-07-01

    This work addresses the refinery scheduling problem using mathematical programming techniques. The solution adopted was to decompose the entire refinery model into a crude oil scheduling and a product scheduling problem. The envelope for the crude oil scheduling problem is composed of a terminal, a pipeline and the crude area of a refinery, including the crude distillation units. The solution method adopted includes a decomposition technique based on the topology of the system. The envelope for the product scheduling comprises all tanks, process units and products found in a refinery. Once crude scheduling decisions are Also available the product scheduling is solved using a rolling horizon algorithm. All models were tested with real data from PETROBRAS' REFAP refinery, located in Canoas, Southern Brazil. (author)

  11. Reducing microbial contamination on wastewater-irrigated lettuce by cessation of irrigation before harvesting

    DEFF Research Database (Denmark)

    Keraita, Bernard; Konradsen, Flemming; Drechsel, Pay

    2007-01-01

    OBJECTIVE: To assess the effectiveness of cessation of irrigation before harvesting in reducing microbial contamination of lettuce irrigated with wastewater in urban vegetable farming in Ghana. METHODS: Assessment was done under actual field conditions with urban vegetable farmers in Ghana. Trials...... were arranged in completely randomized block design and done both in the dry and wet seasons. Seven hundred and twenty-six lettuce samples and 36 water samples were analysed for thermotolerant coliforms and helminth eggs. RESULTS: On average, 0.65 log units for indicator thermotolerant coliforms and 0.......4 helminth eggs per 100 g of lettuce were removed on each non-irrigated day from lettuce in the dry season. This corresponded to a daily loss of 1.4 tonnes/ha of fresh weight of lettuce. As an input for exposure analysis to make risk estimates, the decay coefficient, k, for thermotolerant coliforms was 0...

  12. Drip Irrigation for Commercial Vegetable and Fruit Production

    OpenAIRE

    Maughn, Tiffany; Allen, Niel; Drost, Dan

    2017-01-01

    Drip irrigation is a highly efficient irrigation method well suited to many fruit and vegetable row crops. Drip tubing or tape discharges water to the soil through emitters positioned close to the plant. The drip tubing can be placed uncovered on the soil surface, under plastic mulch, buried in the soil, or suspended above the ground (e.g., on a trellis system). Water application rate is relatively low and irrigations are usually frequent. Properly designed and maintained drip-irrigation syst...

  13. Practical salinity management for leachate irrigation to poplar trees.

    Science.gov (United States)

    Smesrud, Jason K; Duvendack, George D; Obereiner, James M; Jordahl, James L; Madison, Mark F

    2012-01-01

    Landfill leachate can be beneficially reused for irrigation of fiber crops with appropriate attention to nutrient and salinity management. The Riverbend Landfill in Western Oregon has been effectively practicing irrigation of landfill leachate to poplar trees since 1993. Over that time, the site has been adaptively managed to control salinity impacts to the tree crop while beneficially utilizing the applied water and nutrients during each growing season. Representative leachate irrigation water has ranged in concentration of total dissolved solids from 777 to 6,940 mg/L, chloride from 180 to 1,760 mg/L and boron from 3.2 to 7.3 mg/L. Annual leachate irrigation applications have also ranged between 102 and 812 mm/yr. Important conclusions from this site have included: 1) Appropriate tree clone selection and tree stand spacing, thinning, and harvest rotations are critical to maintaining a productive tree stand that is resilient and resistant to salt stress. The most effective combinations have included clones DN-34, OP-367, 184-411, 49-177, and 15-29 planted at spacing of 3.7-m x 1.8-m to 3.7-m x 3.7-m; 2) Leaf tissue boron levels are closely correlated to soil boron levels and can be managed with leaching. When leaf tissue boron levels exceed 200 to 250 mg/kg, signs of salt stress may emerge and should be monitored closely; 3) Salinity from leachate irrigation can be managed to sustain a healthy tree crop by controlling mass loading rates and providing appropriate irrigation blending if necessary. Providing freshwater irrigation following each leachate irrigation and targeting freshwater irrigation as 30 percent of total irrigation water applied has successfully controlled salt impacts to vegetation; and 4) Drip irrigation generally requires more careful attention to long-term soil salinity management than spray irrigation. Moving drip irrigation tubes periodically to prevent the formation of highly saline zones within the soil profile is important. In this paper, a

  14. Irrigation Requirement Estimation Using Vegetation Indices and Inverse Biophysical Modeling

    Science.gov (United States)

    Bounoua, Lahouari; Imhoff, Marc L.; Franks, Shannon

    2010-01-01

    We explore an inverse biophysical modeling process forced by satellite and climatological data to quantify irrigation requirements in semi-arid agricultural areas. We constrain the carbon and water cycles modeled under both equilibrium, balance between vegetation and climate, and non-equilibrium, water added through irrigation. We postulate that the degree to which irrigated dry lands vary from equilibrium climate conditions is related to the amount of irrigation. The amount of water required over and above precipitation is considered as an irrigation requirement. For July, results show that spray irrigation resulted in an additional amount of water of 1.3 mm per occurrence with a frequency of 24.6 hours. In contrast, the drip irrigation required only 0.6 mm every 45.6 hours or 46% of that simulated by the spray irrigation. The modeled estimates account for 87% of the total reported irrigation water use, when soil salinity is not important and 66% in saline lands.

  15. Minimizing Erosion and Agro-Pollutants Transport from Furrow Irrigated Fields to the Nearby Water Body Using Spatially-Explicit Agent Based Model and Decision Optimization Platform

    Science.gov (United States)

    Ghoveisi, H.; Al Dughaishi, U.; Kiker, G.

    2017-12-01

    Maintaining water quality in agricultural watersheds is a worldwide challenge, especially where furrow irrigation is being practiced. The Yakima River Basin watershed in south central Washington State, (USA) is an example of these impacted areas with elevated load of sediments and other agricultural products due to runoff from furrow-irrigated fields. Within the Yakima basin, the Granger Drain watershed (area of 75 km2) is particularly challenged in this regard with more than 400 flood-irrigated individual parcels (area of 21 km2) growing a variety of crops from maize to grapes. Alternatives for improving water quality from furrow-irrigated parcels include vegetated filter strip (VFS) implementation, furrow water application efficiency, polyacrylamide (PAM) application and irrigation scheduling. These alternatives were simulated separately and in combinations to explore potential Best Management Practices (BMPs) for runoff-related-pollution reduction in a spatially explicit, agent based modeling system (QnD:GrangerDrain). Two regulatory scenarios were tested to BMP adoption within individual parcels. A blanket-style regulatory scenario simulated a total of 60 BMP combinations implemented in all 409 furrow-irrigated parcels. A second regulatory scenario simulated the BMPs in 119 furrow-irrigated parcels designated as "hotspots" based on a standard 12 Mg ha-1 seasonal sediment load. The simulated cumulative runoff and sediment loading from all BMP alternatives were ranked using Multiple Criteria Decision Analysis (MCDA), specifically the Stochastic Multi-Attribute Acceptability Analysis (SMAA) method. Several BMP combinations proved successful in reducing loads below a 25 NTU (91 mg L-1) regulatory sediment concentration. The QnD:GrangerDrain simulations and subsequent MCDA ranking revealed that the BMP combinations of 5 m-VFS and high furrow water efficiency were highly ranked alternatives for both the blanket and hotspot scenarios.

  16. [Continent colostomy and colon irrigation].

    Science.gov (United States)

    Kostov, D; Temelkov, T; Kiriazov, E; Ivanov, K; Ignatov, V; Kobakov, G

    2000-01-01

    The authors have studied a functional activity of a continent colostomy at 20 patients, undergone an abdomeno-perineal extirpation of rectum and carried out periodic colonirrigations, during a period of 6 months. A conus type, closed irrigating system has been used. The degree of an incontinency at patients has been compared before and after the beginning of the colonirrigations. The irrigating procedures have reduced spontaneous defications at patients during a week 28 times and have improved the quality of life significantly. The application of colostomy bags has been restricted in 8 (40%) patients. An intraluminal ultrasonographic investigation has been done at 12 (60%) patients at the end of 6 month irrigating period. No changes of the ultrasonographic image of the precolostomic segment of colon has been observed.

  17. Modelling human agency in ancient irrigation

    NARCIS (Netherlands)

    Ertsen, M.W.

    2011-01-01

    Human activity is key in understanding ancient irrigation systems. Results of short term actions build up over time, affecting civilizations on larger temporal and spatial scales. Irrigation systems, with their many entities, social and physical, their many interactions within a changing environment

  18. Irrigated agriculture with limited water supply:Tools for understanding and managing irrigation and crop water use efficiencies

    Science.gov (United States)

    Water availability for irrigated agriculture is declining in both China and the United States due to increased use for power generation, municipalities, industries and environmental protection. Persistent droughts have exacerbated the situation, leading to increases in irrigated area as farmers atte...

  19. Willingness to Pay Additional Water Rate and Irrigation Knowledge of Farmers in Dinar Karakuyu Irrigation Areas in Turkey

    Directory of Open Access Journals (Sweden)

    Mevlüt Gül

    2017-08-01

    Full Text Available Water which has become commodity product which is an important product today. Turkey is not a water rich country. In this study, agricultural enterprises in the field of Irrigation Project in Dinar Karakuyu which was implemented in 1992 by DSI. The study analysed which factors affect the willingness to pay additional irrigation water rate with the help of logit model and the irrigation knowledge of farmers was determined by Likert scale. Dinar Karakuyu irrigation network has begun to lose the function in the region. It was supposed 100% irrigation rate but decreased by approximately 9% today. In this context, DSI (General Directorate of State Hydraulic Works plans to rehabilitation work in the same area. The main material of this study was data obtained from 67 agricultural enterprises through a survey covered by the Irrigation Rehabilitation Project in the province of Afyonkarahisar Karakuyu Dinar. The data was gathered with the help of questionnaires which were answered by farmers in Karakuyu Dinar region. The results indicated that 74.6% of farmers were willingness to pay additional water charge. The data were statistically analysed with the use of the logit model. The model results show that agricultural income, farmers’ educational level, computer ownership, attendance of agricultural training activities, family size and agricultural experience were positive factors affect farmers’ willingness to pay additional water fee.

  20. Armenia - Irrigation Infrastructure

    Data.gov (United States)

    Millennium Challenge Corporation — This study evaluates irrigation infrastructure rehabilitation in Armenia. The study separately examines the impacts of tertiary canals and other large infrastructure...

  1. Comparison of Manual and Automatic Irrigation of Pot Experiments

    DEFF Research Database (Denmark)

    Haahr, Vagner

    1975-01-01

    An air-lift principle for transport of water was adapted for automatic irrigation of experimental pots originally constructed for manual irrigation by the weighing method. The two irrigation techniques were compared in an experiment with increasing amounts of nitrogen fertilizer to spring barley....... Productions of grain and straw and chemical composition were almost the same after the two irrigation methods, and it was concluded that the laborious manual watering could be replaced by automatic irrigation. Comparison of the yield from individual plants in the pots showed a large difference between centre...... plants and border plants independent of irrigation principle. The increase in yield per pot with increasing N fertilization was at the highest N level caused only by an increase in yield of the border plants....

  2. Effect of Irrigation with Reclaimed Water on Fruit Characteristics and Photosynthesis of Olive Trees under Two Irrigation Systems

    Directory of Open Access Journals (Sweden)

    N. Ashrafi

    2016-02-01

    Full Text Available Introduction: Olive (Olea europaea L. trees are mainly cultivated in the Mediterranean area and are grown for their oil or processed as table olives. Despite the fact that olive is known to be resistant to drought conditions due to its anatomical, physiological, and biochemical adaptations to drought stress, reports indicate that the olive can be adversely affected by drought stress, which has a negative effect on the growth of olive trees. In the absence of adequate supplies of water, the demand for water can be met by using improved irrigation methods or by using reclaimed water (RW. Reports have shown that recycled water has been used successfully for irrigating olive orchards with no negative effects on plant growth.Attention has been paid to reclaimed water as one of the most significant available water resources used in agriculture around large cities in arid and semi-arid regions. On the other hand, irrigation efficiency is low and does not meet the demands of farmers.In order to investigate the possibility of irrigating olive orchards with subsurface leakage irrigation (SLI in application of reclaimed water, an experiment was carried out with the aim of investigating the effect of reclaimed water on photosynthetic indices and morphological properties of olive fruit. Materials and Methods: Research was conducted using a split-plot experimental design with two factors (irrigation system and water quality on the campus of Isfahan University of Technology in Isfahan, Iran, on a sandy-clay soil with a pH of 7.5 and electrical conductivity (EC of 2.48 dSm-1.PVC leaky tubes were used for the SLI system. The SLI system was installed 40 cm from the crown of each tree at a depth of 30 - 40 cm.At the end of the experiment fruit yield, weight per fruit, volume, length and firmness were calculated. A portable gas exchange system (Li-6400., LICOR, Lincoln, NE, USA was used to measure the net rate photosynthesis (A, the internal partial pressure CO2

  3. Irrigation development and management in Ghana: Prospects and ...

    African Journals Online (AJOL)

    ... existing schemes. It is envisaged that irrigation will be seen in its right perspective as a multidisciplinary activity to ensure the success of schemes. There is the need for running a postgraduate programme in irrigation at the KNUST to enhance the nations efforts at developing and managing irrigation projects successfully.

  4. Irrigation Depletions 1928-1989 : 1990 Level of Irrigation, Snake Yakima and Deschutes River Basins.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administation; A.G. Crook Company

    1993-07-01

    The vast amount of irrigation in relation to the available water and extensive system of reservoirs located in the Snake River Basin above Brownlee reservoir precludes this area from using methods such as Blaney-Criddle for estimating irrigation depletions. Also the hydrology, irrigation growth patterns, and water supply problems are unique and complex. Therefore regulation studies were utilized to reflect the net effect on streamflow of the changes in irrigated acreage in terms of corresponding changes in storage regulation and in the amount of water depleted and diverted from and returned to the river system. The regulation study for 1990 conditions was conducted by the Idaho Department of Water Resources. The end product of the basin simulation is 61 years of regulated flows at various points in the river system that are based on 1990 conditions. Data used by the Idaho Department of Water Resources is presented in this section and includes natural gains to the river system and diversions from the river system based on a 1990 level of development and operation criteria. Additional information can be obtained for an Idaho Department of Water Resources Open-File Report ``Stream Flows in the Snake River Basin 1989 Conditions of Use and Management`` dated June 1991. Similar considerations apply to the Yakima and Deschutes river basins.

  5. Automated Irrigation System for Greenhouse Monitoring

    Science.gov (United States)

    Sivagami, A.; Hareeshvare, U.; Maheshwar, S.; Venkatachalapathy, V. S. K.

    2018-06-01

    The continuous requirement for the food needs the rapid improvement in food production technology. The economy of food production is mainly dependent on agriculture and the weather conditions, which are isotropic and thus we are not able to utilize the whole agricultural resources. The main reason is the deficiency of rainfall and paucity in land reservoir water. The continuous withdrawal water from the ground reduces the water level resulting in most of the land to come under the arid. In the field of cultivation, use of appropriate method of irrigation plays a vital role. Drip irrigation is a renowned methodology which is very economical and proficient. When the conventional drip irrigation system is followed, the farmer has to tag along the irrigation timetable, which is different for diverse crops. The current work makes the drip irrigation system an automated one, thereby the farmer doesn't want to follow any timetable since the sensor senses the soil moisture content and based on it supplies the water. Moreover the practice of economical sensors and the simple circuitry makes this project as an inexpensive product, which can be bought even by an underprivileged farmer. The current project is best suited for places where water is limited and has to be used in limited quantity.

  6. Automated Irrigation System for Greenhouse Monitoring

    Science.gov (United States)

    Sivagami, A.; Hareeshvare, U.; Maheshwar, S.; Venkatachalapathy, V. S. K.

    2018-03-01

    The continuous requirement for the food needs the rapid improvement in food production technology. The economy of food production is mainly dependent on agriculture and the weather conditions, which are isotropic and thus we are not able to utilize the whole agricultural resources. The main reason is the deficiency of rainfall and paucity in land reservoir water. The continuous withdrawal water from the ground reduces the water level resulting in most of the land to come under the arid. In the field of cultivation, use of appropriate method of irrigation plays a vital role. Drip irrigation is a renowned methodology which is very economical and proficient. When the conventional drip irrigation system is followed, the farmer has to tag along the irrigation timetable, which is different for diverse crops. The current work makes the drip irrigation system an automated one, thereby the farmer doesn't want to follow any timetable since the sensor senses the soil moisture content and based on it supplies the water. Moreover the practice of economical sensors and the simple circuitry makes this project as an inexpensive product, which can be bought even by an underprivileged farmer. The current project is best suited for places where water is limited and has to be used in limited quantity.

  7. Memory of irrigation effects on hydroclimate and its modeling challenge

    Science.gov (United States)

    Chen, Fei; Xu, Xiaoyu; Barlage, Michael; Rasmussen, Roy; Shen, Shuanghe; Miao, Shiguang; Zhou, Guangsheng

    2018-06-01

    Irrigation modifies land-surface water and energy budgets, and also influences weather and climate. However, current earth-system models, used for weather prediction and climate projection, are still in their infancy stage to consider irrigation effects. This study used long-term data collected from two contrasting (irrigated and rainfed) nearby maize-soybean rotation fields, to study the effects of irrigation memory on local hydroclimate. For a 12 year average, irrigation decreases summer surface-air temperature by less than 1 °C and increases surface humidity by 0.52 g kg‑1. The irrigation cooling effect is more pronounced and longer lasting for maize than for soybean. Irrigation reduces maximum, minimum, and averaged temperature over maize by more than 0.5 °C for the first six days after irrigation, but its temperature effect over soybean is mixed and negligible two or three days after irrigation. Irrigation increases near-surface humidity over maize by about 1 g kg‑1 up to ten days and increases surface humidity over soybean (~ 0.8 g kg‑1) with a similar memory. These differing effects of irrigation memory on temperature and humidity are associated with respective changes in the surface sensible and latent heat fluxes for maize and soybean. These findings highlight great need and challenges for earth-system models to realistically simulate how irrigation effects vary with crop species and with crop growth stages, and to capture complex interactions between agricultural management and water-system components (crop transpiration, precipitation, river, reservoirs, lakes, groundwater, etc.) at various spatial and temporal scales.

  8. The Regularity of Optimal Irrigation Patterns

    Science.gov (United States)

    Morel, Jean-Michel; Santambrogio, Filippo

    2010-02-01

    A branched structure is observable in draining and irrigation systems, in electric power supply systems, and in natural objects like blood vessels, the river basins or the trees. Recent approaches of these networks derive their branched structure from an energy functional whose essential feature is to favor wide routes. Given a flow s in a river, a road, a tube or a wire, the transportation cost per unit length is supposed in these models to be proportional to s α with 0 measure is the Lebesgue density on a smooth open set and the irrigating measure is a single source. In that case we prove that all branches of optimal irrigation trees satisfy an elliptic equation and that their curvature is a bounded measure. In consequence all branching points in the network have a tangent cone made of a finite number of segments, and all other points have a tangent. An explicit counterexample disproves these regularity properties for non-Lebesgue irrigated measures.

  9. Closed chamber globe stabilization and needle capsulorhexis using irrigation hand piece of bimanual irrigation and aspiration system

    Directory of Open Access Journals (Sweden)

    Rai Harminder K

    2005-08-01

    Full Text Available Abstract Background The prerequisites for a good capsulorhexis include a deep, well maintained anterior chamber, globe stabilization and globe manipulation. This helps to achieve a capsulorhexis of optimal size, shape and obtain the best possible position for a red glow under retroillumination. We report the use of irrigation handpiece of bimanual irrigation aspiration system to stabilize the globe, maintain a deep anterior chamber and manipulate the globe to a position of optimal red reflex during needle capsulorhexis in phacoemulsification. Methods Two side ports are made with 20 G MVR 'V' lance knife (Alcon, USA. The irrigation handpiece with irrigation on is introduced into the anterior chamber through one side port and the 26-G cystitome (made from 26-G needle is introduced through the other. The capsolurhexis is completed with the needle. Results Needle capsulorhexis with this technique was used in 30 cases of uncomplicated immature senile cataracts. 10 cases were done under peribulbar anaesthesia and 20 under topical anaesthesia. A complete capsulorhexis was achieved in all cases. Conclusion The irrigating handpiece maintains deep anterior chamber, stabilizes the globe, facilitates pupillary dilatation, and helps in maintaining the eye in the position with optimal red reflex during needle capsulorhexis. This technique is a safe and effective way to perform needle capsulorhexis.

  10. Estimating irrigation water use in the humid eastern United States

    Science.gov (United States)

    Levin, Sara B.; Zarriello, Phillip J.

    2013-01-01

    Accurate accounting of irrigation water use is an important part of the U.S. Geological Survey National Water-Use Information Program and the WaterSMART initiative to help maintain sustainable water resources in the Nation. Irrigation water use in the humid eastern United States is not well characterized because of inadequate reporting and wide variability associated with climate, soils, crops, and farming practices. To better understand irrigation water use in the eastern United States, two types of predictive models were developed and compared by using metered irrigation water-use data for corn, cotton, peanut, and soybean crops in Georgia and turf farms in Rhode Island. Reliable metered irrigation data were limited to these areas. The first predictive model that was developed uses logistic regression to predict the occurrence of irrigation on the basis of antecedent climate conditions. Logistic regression equations were developed for corn, cotton, peanut, and soybean crops by using weekly irrigation water-use data from 36 metered sites in Georgia in 2009 and 2010 and turf farms in Rhode Island from 2000 to 2004. For the weeks when irrigation was predicted to take place, the irrigation water-use volume was estimated by multiplying the average metered irrigation application rate by the irrigated acreage for a given crop. The second predictive model that was developed is a crop-water-demand model that uses a daily soil water balance to estimate the water needs of a crop on a given day based on climate, soil, and plant properties. Crop-water-demand models were developed independently of reported irrigation water-use practices and relied on knowledge of plant properties that are available in the literature. Both modeling approaches require accurate accounting of irrigated area and crop type to estimate total irrigation water use. Water-use estimates from both modeling methods were compared to the metered irrigation data from Rhode Island and Georgia that were used to

  11. Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields

    Science.gov (United States)

    Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan

    2017-08-01

    While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO2 fertilization effect compared to an unconstrained GHG emission scenario.

  12. Charts for Guiding Adjustments of Irrigation Interval to Actual Weather Conditions

    International Nuclear Information System (INIS)

    Kipkorir, E.C.

    2002-01-01

    Major problems in irrigation management at short time-step during the season are unreliability of rainfall and absence of guidance. By considering the climate of region, crop and soil characteristics, the irrigation method and local irrigation practices, this paper presents the concept of irrigation charts. The charts are based on soil water technique. As an example irrigation chart for a typical irrigation system located in the semi-arid area in Naivasha, Kenya is presented. The chart guides the user in adjustment of irrigation interval to the actual weather conditions throughout the growing season. It is believed that the simplicity of the chart makes it a useful tool for a better utilisation of the limited irrigation water

  13. Irrigation water policy analysis using a business simulation game

    Science.gov (United States)

    Buchholz, M.; Holst, G.; Musshoff, O.

    2016-10-01

    Despite numerous studies on farmers' responses to changing irrigation water policies, uncertainties remain about the potential of water pricing schemes and water quotas to reduce irrigation. Thus far, policy impact analysis is predominantly based upon rational choice models that assume behavioral assumptions, such as a perfectly rational profit-maximizing decision maker. Also, econometric techniques are applied which could lack internal validity due to uncontrolled field data. Furthermore, such techniques are not capable of identifying ill-designed policies prior to their implementation. With this in mind, we apply a business simulation game for ex ante policy impact analysis of irrigation water policies at the farm level. Our approach has the potential to reveal the policy-induced behavioral change of the participants in a controlled environment. To do so, we investigate how real farmers from Germany, in an economic experiment, respond to a water pricing scheme and a water quota intending to reduce irrigation. In the business simulation game, the participants manage a "virtual" cash-crop farm for which they make crop allocation and irrigation decisions during several production periods, while facing uncertain product prices and weather conditions. The results reveal that a water quota is able to reduce mean irrigation applications, while a water pricing scheme does not have an impact, even though both policies exhibit equal income effects for the farmers. However, both policies appear to increase the variation of irrigation applications. Compared to a perfectly rational profit-maximizing decision maker, the participants apply less irrigation on average, both when irrigation is not restricted and when a water pricing scheme applies. Moreover, the participants' risk attitude affects the irrigation decisions.

  14. Flow-shop scheduling problem under uncertainties: Review and trends

    Directory of Open Access Journals (Sweden)

    Eliana María González-Neira

    2017-03-01

    Full Text Available Among the different tasks in production logistics, job scheduling is one of the most important at the operational decision-making level to enable organizations to achieve competiveness. Scheduling consists in the allocation of limited resources to activities over time in order to achieve one or more optimization objectives. Flow-shop (FS scheduling problems encompass the sequencing processes in environments in which the activities or operations are performed in a serial flow. This type of configuration includes assembly lines and the chemical, electronic, food, and metallurgical industries, among others. Scheduling has been mostly investigated for the deterministic cases, in which all parameters are known in advance and do not vary over time. Nevertheless, in real-world situations, events are frequently subject to uncertainties that can affect the decision-making process. Thus, it is important to study scheduling and sequencing activities under uncertainties since they can cause infeasibilities and disturbances. The purpose of this paper is to provide a general overview of the FS scheduling problem under uncertainties and its role in production logistics and to draw up opportunities for further research. To this end, 100 papers about FS and flexible flow-shop scheduling problems published from 2001 to October 2016 were analyzed and classified. Trends in the reviewed literature are presented and finally some research opportunities in the field are proposed.

  15. Chemical colostomy irrigation with glyceryl trinitrate solution.

    Science.gov (United States)

    O'Bichere, A; Bossom, C; Gangoli, S; Green, C; Phillips, R K

    2001-09-01

    Colostomy irrigation may improve patient quality of life, but is time consuming. This study tests the hypothesis that irrigation with glyceryl trinitrate solution, by inducing gastrointestinal smooth muscle relaxation, may accelerate expulsion of stool by passive emptying, thereby reducing irrigation time. Fifteen colostomy irrigators(with more than 3 years' experience) performed washout with tap water compared with water containing 0.025 mg/kg glyceryl trinitrate. Fluid inflow time, total washout time, and hemodynamic changes occurring during glyceryl trinitrate irrigation were documented by an independent observer. Subjects recorded episodes of fecal leakage and overall satisfaction on a visual analog scale. Cramps, headaches, and whether or not a stoma bag was used were expressed as a percentage of number of irrigations. Comparison of fluid inflow time, total washout time, leakage, and satisfaction was by Wilcoxon's signed-rank test and headaches, cramps, and stoma bag use was by McNemar's test. Pulse rate (paired t-test), systolic and diastolic blood pressures (Wilcoxon's test) at 20 and 240 minutes after washout with glyceryl trinitrate solution were compared with baseline. Fifteen patients (9 female), with a mean age of 53 (31-73) years, provided 30 sessions (15 with water and 15 with glyceryl trinitrate). Medians (interquartile ranges) for water vs. glyceryl trinitrate were fluid inflow time 7 (4-10) vs. 4, (3-5; P = 0.001); total washout time 40 (30-55) vs. 21, (15-24; P colostomy irrigation time compared with the generally recommended tap water. Patients suffer fewer leakages and are highly satisfied, but side effects are potential drawbacks. Other colonoplegic agent solutions should now be evaluated.

  16. Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

    Science.gov (United States)

    Williams, N S; Johnston, D

    1980-07-12

    Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complications. The mean time spent managing the stoma was 45 +/- SEM 9 min/24 hours during spontaneous action and 53 +/- 9 min/24 hours during irrigation. This difference was not significant. The numbers of bowel actions weekly were 13 +/ SEM 2 during spontaneous action and 6 +/- 1 during irrigation (p Irrigation reduced odour and flatus in 20 patients and enabled 12 out of 18 to stop using drugs and seven to discard their appliance. Irrigation also improved the social life of 18 patients and the working conditions of eight out of 14. These finding show that some patients may not be suitable for irrigation but that for many it is better than the conventional British method of colostomy management. With modern apparatus the technique is safe.

  17. Experimental study of faecal continence and colostomy irrigation.

    Science.gov (United States)

    O'Bichere, A; Sibbons, P; Doré, C; Green, C; Phillips, R K

    2000-07-01

    Colostomy irrigation is a useful method of achieving faecal continence in selected conditions, but remains largely underutilized because it is time consuming. This study investigated the effect of modifying irrigation technique (route, infusion regimen and pharmacological manipulation) on colonic emptying time in a porcine model. An end-colostomy and caecostomy were fashioned in six pigs. Twenty markers were introduced into the caecum immediately before colonic irrigation. Irrigation route (antegrade or retrograde), infusion regimen (tap water, polyethylene glycol (PEG), 1.5 per cent glycine) and pharmacological agent (glyceryl trinitrate (GTN) 0.25 mg/kg, diltiazem 3.9 mg/kg, bisacodyl 0.25 mg/kg) were assigned to each animal at random. Colonic transit was assessed by quantifying cumulative expelled markers (CEM) and stool every hour for 12 h. Mean CEM at 6 h for bisacodyl, GTN and diltiazem were 18.17, 12.17 and zero respectively; all pairwise differences in means were significant (P irrigation. PEG and glycine enhance emptying similar to bisacodyl and GTN solution. These findings show promise for improved faecal continence by colostomy irrigation and may justify construction of a Malone conduit at the time of colostomy in selected patients who wish to irrigate. Presented in part to the British Society of Gastroenterology in Glasgow, UK, March 1999, and published in abstract form as Gut 1999; 44(Suppl 1): A135

  18. Distillation irrigation: a low-energy process for coupling water purification and drip irrigation

    Science.gov (United States)

    Constantz, J.

    1989-01-01

    A method is proposed for combining solar distillation and drip irrigation to simultaneously desalinize water and apply this water to row crops. In this paper, the basic method is illustrated by a simple device constructed primarily of sheets of plastic, which uses solar energy to distill impaired water and apply the distillate to a widely spaced row crop. To predict the performance of the proposed device, an empirical equation for distillate production, dp, is developed from reported solar still production rates, and a modified Jensen-Haise equation is used to calculate the potential evapotranspiration, et, for a row crop. Monthly values for et and dp are calculated by using a generalized row crop at five locations in the Western United States. Calculated et values range from 1 to 22 cm month-1 and calculated dp values range from 2 to 11 cm month-1, depending on the location, the month, and the crop average. When the sum of dp plus precipitation, dp + P, is compared to et for the case of 50% distillation irrigation system coverage, the results indicate that the crop's et is matched by dp + P, at the cooler locations only. However, when the system coverage is increased to 66%, the crop's et is matched by dp + P even at the hottest location. Potential advantages of distillation irrigation include the ability: (a) to convert impaired water resources to water containing no salts or sediments; and (b) to efficiently and automatically irrigate crops at a rate that is controlled primarily by radiation intensities. The anticipated disadvantages of distillation irrigation include: (a) the high costs of a system, due to the large amounts of sheeting required, the short lifetime of the sheeting, and the physically cumbersome nature of a system; (b) the need for a widely spaced crop to reduce shading of the system by the crop; and (c) the production of a concentrated brine or precipitate, requiring proper off-site disposal. ?? 1989.

  19. Matching soil salinization and cropping systems in communally managed irrigation schemes

    Science.gov (United States)

    Malota, Mphatso; Mchenga, Joshua

    2018-03-01

    Occurrence of soil salinization in irrigation schemes can be a good indicator to introduce high salt tolerant crops in irrigation schemes. This study assessed the level of soil salinization in a communally managed 233 ha Nkhate irrigation scheme in the Lower Shire Valley region of Malawi. Soil samples were collected within the 0-0.4 m soil depth from eight randomly selected irrigation blocks. Irrigation water samples were also collected from five randomly selected locations along the Nkhate River which supplies irrigation water to the scheme. Salinity of both the soil and the irrigation water samples was determined using an electrical conductivity (EC) meter. Analysis of the results indicated that even for very low salinity tolerant crops (ECi water was suitable for irrigation purposes. However, root-zone soil salinity profiles depicted that leaching of salts was not adequate and that the leaching requirement for the scheme needs to be relooked and always be adhered to during irrigation operation. The study concluded that the crop system at the scheme needs to be adjusted to match with prevailing soil and irrigation water salinity levels.

  20. Field trials show the fertilizer value of nitrogen in irrigation water

    Directory of Open Access Journals (Sweden)

    Mike Cahn

    2017-04-01

    Full Text Available Increased regulatory activity designed to protect groundwater from degradation by nitrate-nitrogen (NO3-N is focusing attention on the efficiency of agricultural use of nitrogen (N. One area drawing scrutiny is the way in which growers consider the NO3-N concentration of irrigation water when determining N fertilizer rates. Four drip-irrigated field studies were conducted in the Salinas Valley evaluating the impact of irrigation water NO3-N concentration and irrigation efficiency on the N uptake efficiency of lettuce and broccoli crops. Irrigation with water NO3-N concentrations from 2 to 45 milligrams per liter were compared with periodic fertigation of N fertilizer. The effect of irrigation efficiency was determined by comparing an efficient (110% to 120% of crop evapotranspiration, ETc and an inefficient (160% to 200% of ETc irrigation treatment. Across these trials, NO3-N from irrigation water was at least as efficiently used as fertilizer N; the uptake efficiency of irrigation water NO3-N averaged approximately 80%, and it was not affected by NO3-N concentration or irrigation efficiency.

  1. effect of deficit irrigation on growth and yield of okro

    African Journals Online (AJOL)

    User

    reduce the demand for irrigation water (Boland et al., 1993). Deficit irrigation is another way in which water use efficiency can be maximized for higher yields per unit of irrigation water. Stegman (1982) reported that the yield of maize, sprinkler irrigated to induce a 30 - 40 percent depletion of available water between.

  2. A scanning electron microscopic evaluation of different root canal irrigation regimens Avaliação por microscopia eletrônica de varredura de diferentes regimes irrigantes no canal radicular

    Directory of Open Access Journals (Sweden)

    Chaves Medici Mônika

    2006-09-01

    Full Text Available The purpose of this study was to assess the effectiveness of endodontic irrigants in removing the smear layer from instrumented root canal walls using Scanning Electron Microscopy (SEM. The endodontic irrigants used were: 1% sodium hypochlorite (NaOCl; 1% NaOCl mixed to 17% EDTAC; 2% chlorhexidine gel; and Ricinus communis gel. Photomicrographs of the middle and apical thirds were evaluated with the aid of the Fotoscore - v. 2.0 software. The results indicated that the mixture of sodium hypochlorite and EDTAC completely removed the smear layer from dentinal walls. The other endodontic irrigants were not as efficient in cleansing the root canals.A proposta deste estudo foi avaliar, por meio de microscopia eletrônica de varredura (MEV, a efetividade dos irrigantes endodônticos na remoção da "smear layer" das paredes dos canais radiculares instrumentados. Os irrigantes endodônticos utilizados foram: solução de hipoclorito de sódio a 1%; solução de hipoclorito de sódio a 1% misturado ao EDTAC a 17%, gel de clorexidina a 2% e gel de Ricinus communis. Fotomicrografias dos terços médio e apical foram avaliadas com o auxílio do software Fotoscore - versão 2.0. Os resultados indicaram que a mistura da solução de hipoclorito de sódio e EDTAC removeu eficientemente a "smear layer" das paredes dentinárias. Os demais irrigantes endodônticos não foram tão eficientes na limpeza dos canais.

  3. Precision overhead irrigation is suitable for several Central Valley crops

    Directory of Open Access Journals (Sweden)

    Jeffrey P. Mitchell

    2016-04-01

    Full Text Available Overhead systems are the dominant irrigation technology in many parts of the world, but they are not widely used in California even though they have higher water application efficiency than furrow irrigation systems and lower labor requirements than drip systems. With water and labor perennial concerns in California, the suitability of overhead systems merits consideration. From 2008 through 2013, in studies near Five Points, California, we evaluated overhead irrigation for wheat, corn, cotton, tomato, onion and broccoli as an alternative to furrow and drip irrigation. With the exception of tomato, equal or increased yields were achieved with overhead irrigation. Many variables are involved in the choice of an irrigation system, but our results suggest that, with more research to support best management practices, overhead irrigation may be useful to a wider set of California farmers than currently use it.

  4. INTEGRATED WATER MANAGEMENT AND DURABILITY OF LANDSCAPE OF PUBLIC IRRIGATED AREAS IN TUNISIA: CASES OF PUBLIC IRRIGATED AREAS OF CHOTT-MARIEM AND MORNAG

    OpenAIRE

    Abdelkarim Hamrita; Amira Boussetta; Rafael Mata Olmo; Mehdi Saqalli; Hichem Rejeb

    2017-01-01

    An important part of the landscape of irrigated areas in Tunisia is the result of morphology, organization and operation of agricultural policies implemented since independence, aimed at optimizing the exploitation of the best soils and natural resources, particularly water and productive crop intensification. The sustainability of the landscape of public irrigated areas has a strong bonding with the resources of irrigation water and their states of management. The scarcity of irrigation wate...

  5. Effects of Supplemental Irrigation on Yield and Growth Indices of Three

    Directory of Open Access Journals (Sweden)

    M. Parsa

    2012-04-01

    Full Text Available In order to investigate the effects of different irrigation regimes on yield and growth indices of three chickpea cultivars, an experiment was conducted during the 2007 growing season at Mashhad (Iran. Six irrigation regimes including I1; full irrigation, I2; irrigation at branching, I3; irrigation at flowering, I4; irrigation at pod formation, I5; irrigation at seed filling stage and I6; dry farming without irrigation (main factors. Three Kabuli chickpea cultivars ILC482, Jam, Karaj 12-60-31 (sub factors in a spilt block experiment based on randomized block design with three replications. There were significant differences between supplemental irrigation levels on grain yield. The results showed that grain yield in supplemental irrigation at flowering stage was more than to supplemental irrigation at branching, podding and seed filling stages (respectively 3.3, 3.1 and 23%. Within the three cultivars, grain yield, biological yield and harvest index were highest and lowest in ILC482 and Karaj 12-60-31 cultivars respectively. The results showed that supplemental irrigation at flowering stage increased dry matter, leaf area index, crop growth rate, relative growth rate and net assimilation rate. The results showed that flowering stage in chickpea cultivars was sensitive to drought stress so, ILC482 cultivar also showed more tolerance to water stress condition.

  6. Evaluation of potential water conservation using site-specific irrigation

    Science.gov (United States)

    With the advent of site-specific variable-rate irrigation (VRI) systems, irrigation can be spatially managed within sub-field-sized zones. Spatial irrigation management can optimize spatial water use efficiency and may conserve water. Spatial VRI systems are currently being managed by consultants ...

  7. Sustainable Irrigation Development in the White Volta Sub-Basin

    NARCIS (Netherlands)

    Ofosu, E.A.

    2011-01-01

    This study on sustainable irrigation development identified growing markets for irrigated products as an important driving force behind the expansion of irrigation which has given rise to new technologies. The new technologies have spread because they gave farmers direct control over water sources.

  8. Ring Irrigation System (RIS) design through customer preference representation

    OpenAIRE

    Ridwan Infandra I.Z.; Rianmora Suchada; Werawatganon Siwat

    2018-01-01

    In agricultural field, irrigation is one of the most interesting considerations affecting the rate of plant growth and development. Micro-irrigation as the dripping or sprinkle method is one of the irrigation types that applies the small amount of water for fulfilling the humidity requirement. The most important factors affecting the demand of water for plants are soil conditions and effect of climatic factors. With less human labour required, to improve the irrigation method from the recent ...

  9. National All Schedules Prescription Electronic Reporting Act (NASPER): balancing substance abuse and medical necessity.

    Science.gov (United States)

    Manchikanti, Laxmaiah; Brown, Keith R; Singh, Vijay

    2002-07-01

    The National All Schedules Prescription Electronic Reporting Act, or NASPER, is a bill proposed by the American Society of Interventional Pain Physicians to provide and improve patient access with quality care, and protect patients and physicians from deleterious effects of controlled substance misuse, abuse and trafficking. Controlled prescription drugs, including narcotic analgesics, anxiolytics, anti-depressants, stimulants, and sedative-hypnotics play a significant and legitimate role in interventional pain management practices in managing chronic pain and related disorders. Based on the 1997 household survey on drug abuse it is estimated that 76.9 million Americans had used an illicit drug at least once in their life. In 1997, 4.2 million people used analgesics, 2.1 million used tranquillizers, and an additional 2.3 million people used various other drugs, including sedatives, tranquillizers, etc. The non-medical use of prescription drugs exceeds that of all illicit substances except for marijuana and hashish. The report on epidemiology trends in drug abuse, based on community epidemiology work group analysis showed continued increase of abuse of prescription drugs in urban, suburban, and rural areas. The most commonly abused drugs include oxycodone, hydrocodone, hydromorphone, morphine, codeine, clonazepam, alprazolam, lorazepam, diazepam and carisoprodol. The diversion of prescription controlled substances to illicit channels is a public health and safety issue. This review describes the role of controlled substances in chronic pain management, prevalence and economic impact of controlled substance abuse, prescription accountability, effectiveness of prescription monitoring programs, and rationale for national controlled substance electronic reporting system.

  10. Stability of Adrenaline in Irrigating Solution for Intraocular Surgery.

    Science.gov (United States)

    Shibata, Yuuka; Kimura, Yasuhiro; Taogoshi, Takanori; Matsuo, Hiroaki; Kihira, Kenji

    2016-01-01

    Intraocular irrigating solution containing 1 µg/mL adrenaline is widely used during cataract surgery to maintain pupil dilation. Prepared intraocular irrigating solutions are recommended for use within 6 h. After the irrigating solution is admistered for dilution, the adrenaline may become oxidized, and this may result in a decrease in its biological activity. However, the stability of adrenaline in intraocular irrigating solution is not fully understood. The aim of this study was to evaluate the stability of adrenaline in clinically used irrigating solutions of varying pH. Six hours after mixing, the adrenaline percentages remaining were 90.6%±3.7 (pH 7.2), 91.1%±2.2 (pH 7.5), and 65.2%±2.8 (pH 8.0) of the initial concentration. One hour after mixing, the percentages remaining were 97.6%±2.0 (pH 7.2), 97.4%±2.7 (pH 7.5), and 95.6%±3.3 (pH 8.0). The degradation was especially remarkable and time dependent in the solution at pH 8.0. These results indicate that the concentration of adrenaline is decreased after preparation. Moreover, we investigated the influence of sodium bisulfite on adrenaline stability in irrigating solution. The percentage adrenaline remaining at 6 h after mixing in irrigating solution (pH 8.0) containing sodium bisulfite at 0.5 µg/mL (concentration in irrigating solution) or at 500 µg/mL (concentration in the undiluted adrenaline preparation) were 57.5 and 97.3%, respectively. Therefore, the low concentration of sodium bisulfite in the irrigating solution may be a cause of the adrenaline loss. In conclusion, intraocular irrigation solution with adrenaline should be prepared just prior to its use in surgery.

  11. Irrigation et paludisme : un couple infernal?

    Directory of Open Access Journals (Sweden)

    Mergeai, G.

    2016-01-01

    Full Text Available Irrigation and Malaria - a Terrible Combination?. Increasing agricultural productivity is a priority in most of the developing countries and using irrigation is one of the most efficient ways of achieving this goal. Almost half a billion people in the world contract malaria every year and approximately one million die as a result. The majority of these victims are farmers or members of their families. In infected areas, malaria continues to have major negative impacts on agricultural productivity. For example, in the Equateur province of the DRC, after access to production means, fevers are considered the second biggest obstacle to the development of agricultural activities. In the Ivory Coast, a study has shown that growers suffering from malaria were about half as productive as their healthy colleagues. The disease often strikes at the start of the rainy season when work begins again in the fields. It reduces the amount of land cultivated and affects the amount of care taken with crops. Agricultural practices influence the risk of contracting malaria. Irrigation, in particular, can encourage the proliferation of vectors of the disease and make it more likely to spread. This tendency can be observed in many locations where irrigated rice production is on the increase. Paradoxically, however, an increased number of mosquitoes does not systematically result in more malaria. In Ethiopia, malaria is more prevalent close to the micro-dams sponsored by the government, whereas, in Tanzania, there is less malaria in irrigated areas. Various theories can be put forward in order to explain this paradox. In particular, increased income due to higher rice yields enables farmers to purchase insecticide-treated mosquito nets. It also allows them to eat better, which strengthens their immune systems. It also appears that the negative impact of irrigation systems is greater in areas, in which immunity levels were low in the population prior to the creation of

  12. NUTRIENT CONTENT IN SUNFLOWERS IRRIGATED WITH OIL EXPLORATION WATER

    Directory of Open Access Journals (Sweden)

    ADERVAN FERNANDES SOUSA

    2016-01-01

    Full Text Available Irrigation using produced water, which is generated during crude oil and gas recovery and treated by the exploration industry, could be an option for irrigated agriculture in semiarid regions. To determine the viability of this option, the effects of this treated water on the nutritional status of plants should be assessed. For this purpose, we examined the nutritional changes in sunflowers after they were irrigated with oil - produced water and the effects of this water on plant biomass and seed production. The sunflower cultivar BRS 321 was grown for three crop cycles in areas irrigated with filtered produced water (FPW, reverse osmosis - treated produced water (OPW, or ground water (GW. At the end of each cycle, roots, shoots, and seeds were collected to examine their nutrient concentrations. Produced water irrigation affected nutrient accumulation in the sunflower plants. OPW irrigation promoted the accumulation of Ca, Na, N, P, and Mg. FPW irrigation favored the accumulation of Na in both roots and shoots, and biomass and seed production were negatively affected. The Na in the shoots of plants irrigated with FPW increased throughout the three crop cycles. Under controlled conditions, it is possible to reuse reverse osmosis - treated produced water in agriculture. However, more long - term research is needed to understand its cumulative effects on the chemical and biological properties of the soil and crop production.

  13. Dealing with drought in irrigated agriculture through insurance schemes: an application to an irrigation district in Southern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, M.; Bielza, J.; Garrido, A.; Iglesias, A.

    2015-07-01

    Hydrological drought is expected to have an increasing impact on both crop and fruit yields in arid and semi-arid regions. Some existing crop insurance schemes provide coverage against water deficits in rain-fed agriculture. The Prevented Planting Program in the USA covers against drought for irrigated agriculture. However, drought insurance for irrigated agriculture is still a challenge for companies and institutions because of the complexity of the design and implementation of this type of insurance. Few studies have attempted to evaluate the risk of loss due to irrigation water scarcity using both stand-alone production functions and crop simulation models. This paper’s contributions are that it evaluates the suitability of AquaCrop for calculating drought insurance premiums for irrigated agriculture and that it discusses contract conditions and insurance design for hydrological drought risk coverage as part of a traditional insurance product, with on-field loss assessment in combination with a trigger index. This method was applied to an irrigation district in southern Spain. Our insurance premium calculation showed that it is feasible to apply this method provided that its data requirements are met, such as a large enough set of reliable small-scale yield and irrigation time series data, especially soil data, to calibrate AquaCrop. The choice of a trigger index should not be underestimated because it proved to have a decisive influence on insurance premiums and indemnities. Our discussion of the contract conditions shows that hydrological drought insurance must comply with a series of constraints in order to avoid moral hazard and basis risk. (Author)

  14. Dealing with drought in irrigated agriculture through insurance schemes: an application to an irrigation district in Southern Spain

    Directory of Open Access Journals (Sweden)

    Jorge Ruiz

    2015-12-01

    Full Text Available Hydrological drought is expected to have an increasing impact on both crop and fruit yields in arid and semi-arid regions. Some existing crop insurance schemes provide coverage against water deficits in rain-fed agriculture. The Prevented Planting Program in the USA covers against drought for irrigated agriculture. However, drought insurance for irrigated agriculture is still a challenge for companies and institutions because of the complexity of the design and implementation of this type of insurance. Few studies have attempted to evaluate the risk of loss due to irrigation water scarcity using both stand-alone production functions and crop simulation models. This paper’s contributions are that it evaluates the suitability of AquaCrop for calculating drought insurance premiums for irrigated agriculture and that it discusses contract conditions and insurance design for hydrological drought risk coverage as part of a traditional insurance product, with on-field loss assessment in combination with a trigger index. This method was applied to an irrigation district in southern Spain. Our insurance premium calculation showed that it is feasible to apply this method provided that its data requirements are met, such as a large enough set of reliable small-scale yield and irrigation time series data, especially soil data, to calibrate AquaCrop. The choice of a trigger index should not be underestimated because it proved to have a decisive influence on insurance premiums and indemnities. Our discussion of the contract conditions shows that hydrological drought insurance must comply with a series of constraints in order to avoid moral hazard and basis risk.

  15. Using container weights to determine irrigation needs: A simple method

    Science.gov (United States)

    R. Kasten Dumroese; Mark E. Montville; Jeremiah R. Pinto

    2015-01-01

    Proper irrigation can reduce water use, water waste, and incidence of disease. Knowing when to irrigate plants in container nurseries can be determined by weighing containers. This simple method is quantifiable, which is a benefit when more than one worker is responsible for irrigation. Irrigation is necessary when the container weighs some target as a proportion of...

  16. A Fuzzy analytical hierarchy process approach in irrigation networks maintenance

    Science.gov (United States)

    Riza Permana, Angga; Rintis Hadiani, Rr.; Syafi'i

    2017-11-01

    Ponorogo Regency has 440 Irrigation Area with a total area of 17,950 Ha. Due to the limited budget and lack of maintenance cause decreased function on the irrigation. The aim of this study is to make an appropriate system to determine the indices weighted of the rank prioritization criteria for irrigation network maintenance using a fuzzy-based methodology. The criteria that are used such as the physical condition of irrigation networks, area of service, estimated maintenance cost, and efficiency of irrigation water distribution. 26 experts in the field of water resources in the Dinas Pekerjaan Umum were asked to fill out the questionnaire, and the result will be used as a benchmark to determine the rank of irrigation network maintenance priority. The results demonstrate that the physical condition of irrigation networks criterion (W1) = 0,279 has the greatest impact on the assessment process. The area of service (W2) = 0,270, efficiency of irrigation water distribution (W4) = 0,249, and estimated maintenance cost (W3) = 0,202 criteria rank next in effectiveness, respectively. The proposed methodology deals with uncertainty and vague data using triangular fuzzy numbers, and, moreover, it provides a comprehensive decision-making technique to assess maintenance priority on irrigation network.

  17. [Irrigation in colostomies].

    Science.gov (United States)

    Campo, Juana; Lecona, Ana; Caparrós, M Rosario; Barbero, M Antonia; Javier Cerdán, F

    2002-01-01

    The degree of acceptation of irrigation from a colostomy varies ostensibly from some cases to others, therefore, we study what occurs in our medium, separating those patients which have previously undergone other procedures (Group A) from those patients who have been informed and trained about the immediate postoperative period (Group B). 48 patients, 22 or 46% of these patients were considered not apt for irrigation. Of the 26 to whom this procedure was proposed, 14 or 54% accepted. Of these, 5 or 36% abandoned its use while 9 continued its use; this is 64% of those who accepted this procedure, 35% of those to whom it was proposed and 19% of the total study group. 189 patients. This procedure was not recommended to 95 patients, 50%. Of the 94 patients to whom this procedure was proposed, 65 or 69% accepted. Of these, 22 or 34% abandoned its use while 43 continued its use; this is 66% of those; who accepted this procedure, 46% of those to whom it was proposed and 23% of the total study group. In our medium, the practice of irrigation oscillates between 19 and 23% of patients who have undergone a colostomy, without any significant difference referring to the moment when a patient started this procedure. A first report on this study was submitted in the III National Congress for Nursing in Colostomies.

  18. Clinical value of colonic irrigation in patients with continence disturbances.

    Science.gov (United States)

    Briel, J W; Schouten, W R; Vlot, E A; Smits, S; van Kessel, I

    1997-07-01

    Continence disturbances, especially fecal soiling, are difficult to treat. Irrigation of the distal part of the large bowel might be considered as a nonsurgical alternative for patients with impaired continence. This study is aimed at evaluating the clinical value of colonic irrigation. Thirty-two patients (16 females; median age, 47 (range, 23-72) years) were offered colonic irrigation on an ambulatory basis. Sixteen patients suffered from fecal soiling (Group I), whereas the other 16 patients were treated for fecal incontinence (Group II). Patients were instructed by enterostomal therapists how to use a conventional colostomy irrigation set to obtain sufficient irrigation of the distal part of their large bowel. Patients with continence disturbances during the daytime were instructed to introduce 500 to 1,000 ml of warm (38 degrees C) water within 5 to 10 minutes after they passed their first stool. In addition, they were advised to wait until the urge to defecate was felt. Patients with soiling during overnight sleep were advised to irrigate during the evening. To determine clinical outcome, a detailed questionnaire was used. Median duration of follow-up was 18 months. Ten patients discontinued irrigation within the first month of treatment. Symptoms resolved completely in two patients. They believed that there was no need to continue treatment any longer. Irrigation had no effect in two patients. Despite the fact that symptoms resolved, six patients discontinued treatment because they experienced pain (n = 2) or they considered the irrigation to be too time-consuming (n = 4). Twenty-two patients are still performing irrigations. Most patients irrigated the colon in the morning after the first stool was passed. Time needed for washout varied between 10 and 90 minutes. Frequency of irrigations varied from two times per day to two times per week. In Group I, irrigation was found to be beneficial in 92 percent of patients, whereas 60 percent of patients in Group II

  19. Effects of irrigation strategies and soils on field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Plauborg, Finn; Andersen, Mathias Neumann

    2011-01-01

    Root distribution of field grown potatoes (cv. Folva) was studied in 4.32m2 lysimeters and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. Drip irrigation was applied for all irrigations. Irrigations were run in three different soils: coarse sand......, loamy sand, and sandy loam. Irrigation treatments started after tuber bulking and lasted until final harvest with PRD and DI receiving 65% of FI. Potatoes irrigated with water-saving irrigation techniques (PRD and DI) did not show statistically different dry root mass and root length density (RLD, cm...... density in the furrow. Most roots accumulated in the surface layers of coarse sand as compared to the other soil types. In the deep soil profile (30–70 cm) a higher root density was found in loamy sand compared with the sandy loam and coarse sand. Approximately twice the amounts of roots were found below...

  20. Biochar enhances yield and quality of tomato under reduced irrigation

    DEFF Research Database (Denmark)

    Saleem Akhtar, Saqib; Li, Guitong; Andersen, Mathias Neumann

    2014-01-01

    tBiochar is an amendment that can be used for enhancing soil water storage which may increase cropproductivity. The objective of this study was to investigate the effects of biochar on physiology, yield andquality of tomato under different irrigation regimes. From early flowering to fruit maturity...... stages, theplants were subjected to full irrigation (FI), deficit irrigation (DI) and partial root-zone drying irrigation(PRD) and two levels of biochar (0% and 5% by weight). In FI, the plants were irrigated daily to pot waterholding capacity while in DI and PRD, 70% of FI was irrigated on either...... the whole or one side of the pots,respectively. In PRD, irrigation was switched between sides when the soil water content of the dry sidedecreased to 15%. The results showed that addition of biochar increased the soil moisture contents in DIand PRD, which consequently improved physiology, yield, and quality...

  1. Agro-ecology and irrigation technology : comparative research on farmer-managed irrigation systems in the Mid-hills of Nepal

    NARCIS (Netherlands)

    Parajuli, U.N.

    1999-01-01

    Design and management of irrigation infrastructure in farmer managed irrigation systems (FMISs) are strongly influenced by social and agro-ecological conditions of an area. This thesis analyzes the elements of social and agro-ecological conditions in FMISs in the mid-hills of Nepal and

  2. Development of an irrigation control device based on solar radiation and its adaptability for cultivation of high soluble solid tomato fruit in root zone restriction culture

    International Nuclear Information System (INIS)

    Nitta, M.; Shibuya, K.; Kubai, K.; Komatsu, H.; Hosokawa, T.; Nakamura, K.

    2009-01-01

    An irrigation control device based on solar radiation was developed to allow automatic irrigation management for high soluble solid tomato fruit production in root zone restriction culture. Its adaptability for long-term cultivation (planting carried out in early September and harvesting ending in late June) of high soluble solid tomato fruit in root zone restriction culture was examined. The following results were obtained: 1. The control device was composed of generally available electronic parts. A change of setting was possible for the irrigation starting point, the irrigation time period, and the once amount of irrigation. For the first irrigation of the day, one of two irrigation control modes can be chosen; the first determines irrigation dependent on the solar radiation after the irrigated time of the previous day. The second mode irrigates at a set time. 2. The correlation between the total integrated solar radiation and the evapotranspiration rate of tomato plants were investigated. Positive correlations were observed for each month from October to June. Moreover, total integrated solar radiation per unit evapotranspiration was different for each month. 3. In long-term cultivation of tomato fruit using this device, the marketable yield of high soluble solid tomato fruit (more than Brix 8%) was 9.7t/10a. 4. This device exhibited the necessary adaptability for use in long-term cultivation of high soluble solid tomato fruit in root zone restriction culture, by changing the set value of the irrigation starting point and the irrigation time period in accordance with the growth period

  3. Modelling the economic trade-offs of irrigation pipeline investments ...

    African Journals Online (AJOL)

    The Soil Water Irrigation Planning and Energy Management (SWIP-E) mathematical programming model was developed and applied in this paper to provide decision support regarding the optimal mainline pipe diameter, irrigation system delivery capacity and size of the irrigation system. SWIP-E unifies the interrelated ...

  4. Irrigation and fertigation frequencies with nitrogen in the watermelon culture

    Directory of Open Access Journals (Sweden)

    Carlos Newdmar Vieira Fernandes

    2014-06-01

    Full Text Available This study evaluates the influence of different irrigation frequencies and different nitrogen fertigation frequencies on the growth performance of the watermelon (Citrullus lanatus culture. Two experiments were conducted at the Paraguay farm in the Cruz municipality, Ceará, Brazil. They was randomized blocks design with six treatments and four replications. The irrigation frequency experiment consisted of the application of different irrigation frequencies. The treatments were: DM - daily irrigation in the morning with 100% daily dosage; DT - daily irrigation in the afternoon, with 100% daily dosage; DMT - twice daily irrigation, with 50% daily dosage in the morning and 50% daily dosage in the afternoon; 2D - irrigation every two days; 3D - irrigation every three days and 4D - irrigation every four days. To the experiment with different nitrogen fertigation frequencies, the treatments used were: 2F - 2 fertigations in a cycle; 4F - 4 fertigations in a cycle; 8F - 8 fertigations in a cycle; 16F - 16 fertigations in a cycle; 32F - 32 fertigations in a cycle and 64F - 64 fertigations in a cycle. We evaluated the marketable yield (PC, fruit weight (M, polar diameter (DP, equatorial diameter (DE, shell thickness (EC and soluble solids (SS. The irrigation frequency treatments influenced all variables significantly, with twice daily irrigation (DMT, 50% in the morning and the 50% in the afternoon promoting the highest productivity (69.79 t ha-1. The different frequencies of fertigation also significantly influenced all variables, except for the shell thickness, the highest yield (80.69 t ha-1 being obtained with treatment 64 fertigations in a cycle.

  5. Manejo de irrigação para o feijão-de-metro, nas fases vegetativa e produtiva, em ambiente protegido Irrigation scheduling for asparagus bean in vegetative and productive stages in greenhouse

    Directory of Open Access Journals (Sweden)

    Wellington G. da Silva

    2012-09-01

    Full Text Available O manejo adequado da irrigação é uma prática agrícola que requer informações para cada cultura explorada, em particular nas fases fenológicas do ciclo produtivo pois muitas espécies possuem períodos críticos durante os quais o estresse hídrico causa sérias reduções na produção. Este trabalho teve, como objetivo, avaliar o efeito de cinco níveis de potencial matricial de água no solo sobre o crescimento e produção do feijão-de-metro. O experimento foi conduzido em casa de vegetação, na área experimental pertencente ao Departamento de Engenharia da Universidade Federal de Lavras, Lavras, MG. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 5 x 2, com quatro repetições. Os tratamentos foram constituídos de cinco potenciais matriciais de água no solo como indicativos do momento de irrigar (-15, -35, -55, -75 e -95 kPa, em duas fases fenológicas (vegetativa e produtiva, monitorados por sensores instalados a 0,15 m de profundidade. Os resultados permitiram concluir que a fase mais sensível ao déficit hídrico foi a produtiva e que a irrigação realizada no potencial matricial em torno de -15 kPa induziu a melhor resposta da cultura quanto ao desenvolvimento, produção e qualidade das vagens.Proper irrigation water management requires knowledge on each exploited crop; particularly regarding vegetative and productive phases since many species have critical periods during which water stress causes serious yield reductions. This study was undertaken so as to assess the effect of five matric potential levels on asparagus bean growth and yield. The experiment was conducted under greenhouse conditions at the experimental area of Department of Engineering, Federal University of Lavras, Lavras, MG. The experimental design was randomized blocks in factorial 5 x 2. The treatments consisted of five matric potentials as indicative of the irrigation scheduling -15 -35 -55 -75 -95 kPa and at two

  6. Instructions, multiple schedules, and extinction: Distinguishing rule-governed from schedule-controlled behavior.

    Science.gov (United States)

    Hayes, S C; Brownstein, A J; Haas, J R; Greenway, D E

    1986-09-01

    Schedule sensitivity has usually been examined either through a multiple schedule or through changes in schedules after steady-state responding has been established. This study compared the effects of these two procedures when various instructions were given. Fifty-five college students responded in two 32-min sessions under a multiple fixed-ratio 18/differential-reinforcement-of-low-rate 6-s schedule, followed by one session of extinction. Some subjects received no instructions regarding the appropriate rates of responding, whereas others received instructions to respond slowly, rapidly, or both. Relative to the schedule in operation, the instructions were minimal, partially inaccurate, or accurate. When there was little schedule sensitivity in the multiple schedule, there was little in extinction. When apparently schedule-sensitive responding occurred in the multiple schedule, however, sensitivity in extinction occurred only if differential responding in the multiple schedule could not be due to rules supplied by the experimenter. This evidence shows that rule-governed behavior that occurs in the form of schedule-sensitive behavior may not in fact become schedule-sensitive even though it makes contact with the scheduled reinforcers.

  7. Alkaline Sodium Hypochlorite Irrigant and Its Chemical Interactions

    Directory of Open Access Journals (Sweden)

    Patricia P. Wright

    2017-09-01

    Full Text Available Endodontic irrigating solutions may interact chemically with one another. This is important, because even when solutions are not admixed, they will come into contact with one another during an alternating irrigation technique, forming unwanted by-products, which may be toxic or irritant. Mixing or alternating irrigants can also reduce their ability to clean and disinfect the root canal system of teeth by changing their chemical structure with subsequent loss of the active agent, or by inducing precipitate formation in the root canal system. Precipitates occlude dental tubules, resulting in less penetration of antimicrobials and a loss of disinfection efficacy. Sodium hypochlorite is not only a very reactive oxidizing agent, but is also the most commonly used endodontic irrigant. As such, many interactions occurring between it and other irrigants, chelators and other antimicrobials, may occur. Of particular interest is the interaction between sodium hypochlorite and the chelators EDTA, citric acid and etidronate and between sodium hypochlorite and the antimicrobials chlorhexidine, alexidine, MTAD and octenisept.

  8. Field evaluation of deficit irrigation effects on tomato growth ...

    African Journals Online (AJOL)

    Two field experiments were conducted using a common tomato cultivar (GS12) to assess the effect of deficit irrigation (DI) regimes on tomato growth performance, and on root-knot nematode Meloidogyne javanica galling and abundance. Irrigation treatments consisted of five irrigation regimes: 20%, 40%, 60%, 80% and ...

  9. Surge flow irrigation under short field conditions in Egypt

    NARCIS (Netherlands)

    Ismail, S.M.; Depeweg, H.; Schultz, E.

    2004-01-01

    Several studies carried out in long furrows have shown that surge flow irrigation offers the potential of increasing the efficiency of irrigation. The effects of surge flow in short fields, such as in Egypt, are still not well known, however. To investigate the effect of surge flow irrigation in

  10. Evaluation of mulched drip irrigation for cotton in arid Northwest China

    NARCIS (Netherlands)

    Wang, Z.; Jin, M.; Simunek, J.; van Genuchten, M.T.

    2014-01-01

    Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control

  11. Green and blue water footprint reduction in irrigated agriculture: effect of irrigation techniques, irrigation strategies and mulching

    NARCIS (Netherlands)

    Chukalla, Abebe Demissie; Krol, Martinus S.; Hoekstra, Arjen Ysbert

    2015-01-01

    Consumptive water footprint (WF) reduction in irrigated crop production is essential given the increasing competition for freshwater. This study explores the effect of three management practices on the soil water balance and plant growth, specifically on evapotranspiration (ET) and yield (Y) and

  12. Normative structures, collaboration and conflict in irrigation; a case study of the Pillaro North Canal Irrigation System, Ecuadorian Highlands

    Directory of Open Access Journals (Sweden)

    Jaime Hoogesteger

    2015-03-01

    Full Text Available This paper analyzes conflict and collaboration and their relation to normative structures based on a case study of the history and external interventions of the Píllaro North Canal Irrigation System in the Ecuadorian Highlands. It does so by using Ostrom’s framework for analyzing the sustainability of socio-ecological systems together with an analysis of the normative structures that define the governance systems through which the interactions in irrigation systems are mediated. I argue that the external interventions by the state and NGOs imposed a new governance system that undermined the existing normative structures and related organizations, leading to internal conflicts. The case study suggests that a reformulation of irrigation policies and state intervention methodologies in user managed supra-community irrigation systems in the Andes could lead to higher levels of cooperation.

  13. Strategy of Irrigation Branch in Russia

    Science.gov (United States)

    Zeyliger, A.; Ermolaeva, O.

    2012-04-01

    At this moment, at the starting time of the program on restoration of a large irrigation in Russia till 2020, the scientific and technical community of irrigation branch does not have clear vision on how to promote a development of irrigated agriculture and without repeating of mistakes having a place in the past. In many respects absence of a vision is connected to serious backlog of a scientific and technical and informational and technological level of development of domestic irrigation branch from advanced one. Namely such level of development is necessary for the resolving of new problems in new conditions of managing, and also for adequate answers to new challenges from climate and degradation of ground & water resources, as well as a rigorous requirement from an environment. In such important situation for irrigation branch when it is necessary quickly generate a scientific and technical politics for the current decade for maintenance of translation of irrigated agriculture in the Russian Federation on a new highly effective level of development, in our opinion, it is required to carry out open discussion of needs and requirements as well as a research for a adequate solutions. From political point of view a framework organized in FP6 DESIRE 037046 project is an example of good practice that can serve as methodical approach how to organize and develop such processes. From technical point of view a technology of operational management of irrigation at large scale presents a prospective alternative to the current type of management based on planning. From point of view ICT operational management demands creation of a new platform for the professional environment of activity. This platform should allow to perceive processes in real time, at their partial predictability on signals of a straight line and a feedback, within the framework of variability of decision making scenarious, at high resolution and the big ex-awning of sensor controls and the gauges

  14. Automation in irrigation process in family farm with Arduino platform

    Directory of Open Access Journals (Sweden)

    Kianne Crystie Bezerra da Cunha

    2016-03-01

    Full Text Available The small farmers tend not to use mechanical inputs in the irrigation process due to the high cost than conventional irrigation systems have and in other cases, the lack of knowledge and technical guidance makes the farmer theme using the system. Thus, all control and monitoring are made by hand without the aid of machines and this practice can lead to numerous problems from poor irrigation, and water waste, energy, and deficits in production. It is difficult to deduce when to irrigate, or how much water applied in cultivation, measure the soil temperature variables, temperature, and humidity, etc. The objective of this work is to implement an automated irrigation system aimed at family farming that is low cost and accessible to the farmer. The system will be able to monitor all parameters from irrigation. For this to occur, the key characteristics of family farming, Arduino platform, and irrigation were analyzed.

  15. Pond and Irrigation Model (PIM): a tool for simultaneously evaluating pond water availability and crop irrigation demand

    Science.gov (United States)

    Ying Ouyang; Gary Feng; Theodor D. Leininger; John Read; Johnie N. Jenkins

    2018-01-01

    Agricultural ponds are an important alternative source of water for crop irrigation to conserve surface and ground water resources. In recent years more such ponds have been constructed in Mississippi and around the world. There is currently, however, a lack of a tool to simultaneously estimate crop irrigation demand and pond water availability. In this study, a Pond-...

  16. Syringe irrigation: blending endodontics and fluid dynamics

    NARCIS (Netherlands)

    Boutsioukis, C.; van der Sluis, L.W.M.; Basrani, B.

    2015-01-01

    Syringe irrigation remains a widely used irrigant delivery method during root canal treatment. An interdisciplinary approach involving well-established methods from the field of fluid dynamics can provide new insights into the mechanisms involved in cleaning and disinfection of the root canal system

  17. Syringe irrigation: blending endodontics and fluid dynamics

    NARCIS (Netherlands)

    Boutsioukis, Christos; van der Sluis, Lucas; Basrani, Bettina

    2015-01-01

    This book reviews the available information on bacterial disinfection in endodontics, with emphasis on the chemical treatment of root canals based on current understanding of the process of irrigation. It describes recent advances in knowledge of the chemistry associated with irrigants and delivery

  18. Evaluation of smear layer removal and marginal adaptation of root canal sealer after final irrigation using ethylenediaminetetraacetic, peracetic, and etidronic acids with different concentrations.

    Science.gov (United States)

    Ulusoy, Özgür İlke; Zeyrek, Salev; Çelik, Bülent

    2017-07-01

    The purpose of this study was to investigate the effects of different irrigation solutions on the smear layer removal and marginal adaptation of a resin-based sealer to root canal dentine. A total of 152 instrumented roots were irrigated with the following irrigants: 9,18% etidronic acid (HEBP), 0.5, 1,2% peracetic acid (PAA), 17% ethylenediaminetetraacetic acid (EDTA), saline. The amount of smear layer was evaluated using scanning electron microscope (SEM) in seventy root samples. Eighty-two roots were filled with AH Plus and gutta-percha. Slices obtained from apical third of each specimen were viewed with SEM to assess marginal adaptation. Use of 9% and 18% HEBP resulted in more efficient smear layer removal in the apical third than the other chelators (p acid is a promising candidate for final irrigation of root canals. © 2017 Wiley Periodicals, Inc.

  19. Schedules of Controlled Substances: Temporary Placement of 4-Fluoroisobutyryl Fentanyl into Schedule I. Temporary scheduling order.

    Science.gov (United States)

    2017-05-03

    The Administrator of the Drug Enforcement Administration is issuing this temporary scheduling order to schedule the synthetic opioid, N-(4-fluorophenyl)-N-(1-phenethylpiperidin-4-yl)isobutyramide (4-fluoroisobutyryl fentanyl or para-fluoroisobutyryl fentanyl), and its isomers, esters, ethers, salts and salts of isomers, esters, and ethers, into schedule I pursuant to the temporary scheduling provisions of the Controlled Substances Act. This action is based on a finding by the Administrator that the placement of 4-fluoroisobutyryl fentanyl into schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. As a result of this order, the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances will be imposed on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle, 4-fluoroisobutyryl fentanyl.

  20. The phenology of malaria mosquitos in irrigated rice fields in Mali

    NARCIS (Netherlands)

    Klinkenberg, E.; Takken, W.; Huibers, F.P.; Touré, Y.T.

    2003-01-01

    A field study was carried out in the large-scale rice irrigation scheme of the Office du Niger in Mali to investigate the relation between anopheline mosquito larval development and small-scale differences in irrigation practices, such as water level, irrigation application and irrigation frequency.

  1. Alternate partial root-zone drying irrigation improves fruit quality in tomatoes

    DEFF Research Database (Denmark)

    Sun, Y.; Holm, Peter Engelund; Liu, Fulai

    2014-01-01

    Alternate partial root-zone drying (PRD) irrigation and deficit irrigation (DI) are water-saving irrigation strategies. Here, comparative effects of PRD and DI on fruit quality of tomato (Solanum lycopersicum L.) were investigated. The results showed that the irrigation treatments had no effect o...

  2. Results of a 5-Week Schedule of Modern Total Skin Electron Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Stephen Lloyd, E-mail: stephen.morris@gstt.nhs.uk [St Johns Institute of Dermatology, Guys and St Thomas Hospital, London (United Kingdom); McGovern, Mark; Bayne, Sally; Wain, Mary; Child, Fiona; Whittaker, Sean [St Johns Institute of Dermatology, Guys and St Thomas Hospital, London (United Kingdom)

    2013-08-01

    Purpose: To report the outcomes of a 5-week schedule of total skin electron beam radiation therapy (TSEB) for mycosis fungoides (MF). Methods: Over 5 years, 41 patients with confirmed MF were treated with a modern TSEB technique delivering 30 Gy in 20 fractions over 5 weeks to the whole skin surface. Data were collected prospectively and entered into the skin tumor unit research database. Skin modified skin weighted assessment tool score data were collected to determine response, duration of response, survival, and toxicity. The outcomes were analyzed according to the patient's stage before TSEB, prognostic factors, and adjuvant treatments. Results: Seventeen patients were stage 1B, 19 were stage IIB, 3 were stage III, and 2 were stage IV. The overall response rate was 95%, with a complete response rate of 51%. Seventy-six percent of patients had relapsed at median follow-up of 18 months. The median time to relapse was 12 months, to systemic therapy was 15 months, and to modified skin weighted assessment tool progression above baseline was 44 months. The complete response rate was 59% in stage IB and 47% in stage IIB patients. The median time to skin relapse was longer in stage IB compared with stage IIB, 18 months versus 9 months. The median time to systemic therapy was longer in stage IB compared with stage IIB, >56 months versus 8 months. The median overall survival was 35 months: >56 months for stage IB, 25 months for stage IIB, 46 months for stage III, and 23.5 months for stage IV. Fifteen patients received adjuvant psoralen + ultraviolet A treatment with no difference seen in the time to relapse. Conclusions: This 5-week schedule of TSEB for MF has a high response rate with comparable duration of response to other regimens. Future studies are needed to find adjuvant and combination treatments to improve the duration of response.

  3. Multiple-use Management of Irrigation Systems: Technical Constraints and Challenges

    Science.gov (United States)

    Gowing, J.; Li, Q.; Mayilswami, C.; Gunawardhana, K.

    It is now widely recognised that many irrigation systems, originally planned only for irrigation supply, are de facto multiple-use systems. However, the importance of non- irrigation uses (such as bathing, laundry, livestock watering and fishing), to the liveli- hoods of the rural poor has generally been ignored. This has significant implications for irrigation engineers, water resources managers and other decision-makers. An im- proved understanding of competition and complementarity between these uses and irrigation demands is essential for effective multiple-use management of irrigation systems.This paper presents a study of multiple-use management, where the focus is on integrating aquaculture within irrigation systems with and without secondary storage. The Lower Bhavani scheme in South India and Mahaweli System H in Sri- Lanka were selected as representative smallholder irrigation schemes: - The Lower Bhavani scheme comprises a 200km contour canal serving a command area of 78,500ha. Apart from the main dam, there are no storage structures within the irriga- tion system. - Mahaweli System H comprises a command area of 43,000ha served by three main canals. The feature of particular interest in this scheme is the large number of secondary storage structures (known locally as tanks), which are in- tegrated within the canal network. It is apparent from these two sites and from studies elsewhere that non-irrigation uses are important to the livelihoods of the local peo- ple, but these uses are largely opportunistic. The failure to give explicit recognition to non-irrigation uses has important implications for assessments of economic per- formance and water productivity of irrigation systems. However, any attempt to give proper recognition to these alternative uses also has implication for irrigation project management. This paper describes a detailed study of water management in the two irrigation systems. The method of investigation involves in-depth studies in

  4. Reform of irrigation management and investment policy in African development

    Directory of Open Access Journals (Sweden)

    KW Easter

    2004-11-01

    Full Text Available This paper examines the reform of water and irrigation management in Africa and compares it with similar reforms in Asia.  Several things are evident from the review.  First, Sub-Saharan Africa (SSA is at an earlier stage of irrigation development and reform than Asia.  Second, the articulated need for reform is much stronger in Asia than it is in SSA.  Third, the productivity of small-scale irrigated farms is significantly lower in SSA compared to Asia.  Thus any irrigation investment strategy in SSA should be different from Asia and focus on increasing small-farm productivity as well as small-scale irrigation projects.  Finally, all direct government irrigation investments should be done jointly with decisions regarding the type of project management.

  5. Dwarf cashew growth irrigated with saline waters

    Directory of Open Access Journals (Sweden)

    Hugo Orlando Carvallo Guerra

    2009-12-01

    Full Text Available The cashew production is one of the most important agricultural activities from the social-economical viewpoint for the North East of Brazil; besides to produce a great deal of hand labor, it is very important as an exporting commodity. The inadequate use of irrigation in the semi arid regions of the North East of Brazil has induced soil salinization and consequently problems for the irrigated agriculture. In spite of this, few works have been conducted to study the effect of saline stress on the growth and development of the cashew. Because of the lack of information for this crop, an experiment was conducted to study the effect of salinity stress on the phytomass production and nutrient accumulation on the different organs of the precocious dwarf cashew (Anacardium occidentale L. clone CCP76. The study was conducted under controlled conditions using as statistical scheme a randomized block design factorial with six replicates. Five salinity treatments were considered for the irrigation water (electrical conductivities of 0.8, 1.6, 2.4, 3.2 and 4.0 dS m-1 at 25oC. The increasing in salinity of the irrigation water reduced the phytomass at different organs of the studied plant. The nitrogen, phosphorus, potassium, chloride and sodium in the plant varied with the salinity of the irrigation water according with the part of the plant analyzed; in some parts increased, in others decreased, in others increased initially and decreased afterwards, and finally, in other part of the plant the salinity of the irrigation water did not affect the nutrient concentration.

  6. Optimization of irrigation water in stone fruit and table grapes

    Science.gov (United States)

    de la Rosa, Jose Mª; Castillo, Cristina; Temnani, Abdel; Pérez-Pastor, Alejandro

    2017-04-01

    In water scarcity areas, it must be highlighted that the maximum productions of the crops do not necessarily imply maximum profitability. Therefore, during the last years a special interest in the development of deficit irrigation strategies based on significant reductions of the seasonal ET without affecting production or quality has been observed. The strategies of regulated deficit irrigation (RDI) are based on the reduction of water supply during non critical periods, the covering of water needs during critical periods and maximizing, at the same time, the production by unit of applied water. The main objective of this experiment was to implement, demonstrate and disseminate a sustainable irrigation strategy based on deficit irrigation to promote its large scale acceptance and use in woody crops in Mediterranean agroecosystems, characterized by water scarcity, without affecting the quality standards demanded by exportation markets. Five demonstration plots were established in representative crops of the irrigating community of Campotejar (Murcia, Spain): i) Peach trees, cv. catherina in the "Periquitos" farm; ii) Apricot trees, cv. "Red Carlet" in "La Hoya del Fenazar" farm; iii) Nectarine trees, cv. Viowhite in "Agrícola Don Fernando" farm; iv) Table grape, cv "Crimson Seedless" in "La Hornera" farm; and v) Paraguayan cv. carioca in "The Hornera" farm. In each demonstration plot, at least two irrigation treatments were established: i) Control (CTL), irrigated to ensure non-limiting water conditions (120% of crop evapotranspiration) and ii) Regulated deficit irrigation (RDI) irrigated as CTL during critical periods and decreasing irrigation in non-critical periods. The plant water status indicators evaluated were midday stem water potential and Trunk Diameter Fluctuation derived indices: maximum daily shrinkage (MDS) and trunk daily growth rate (TGR); vegetative growth of the different crops from trunk diameter and pruning dry weight, fruit growth and fruit

  7. LOW COST SMART SOLAR POWERED AUTOMATIC IRRIGATION SYSTEM

    OpenAIRE

    Hinsermu Alemayehu*, Kena Likassa

    2016-01-01

    In developing countries Photovoltaic energy can find many applications in agriculture, providing electrical energy in various cases, particularly OFF grid and desert area. Today Modern irrigation methods in developing country are needed to fulfill the food demands. Although in these countries Ethiopia, there are many diesel engine operated and rare solar operated water pumps for irrigation; but due to the running cost of diesel and capital cost of photovoltaic irrigation system. So Photovolta...

  8. Agricultural irrigated land-use inventory for Polk County, Florida, 2016

    Science.gov (United States)

    Marella, Richard L.; Berry, Darbi; Dixon, Joann F.

    2017-08-16

    An accurate inventory of irrigated crop acreage is not available at the level of resolution needed to better estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage was developed for Polk County, Florida, during the 2016 growing season. This cooperative project between the U.S. Geological Survey and the Office of Agricultural Water Policy of the Florida Department of Agriculture and Consumer Services is part of an effort to improve estimates of water use and projections of future demands across all counties in the State. The irrigated areas were delineated by using land-use data provided by the Florida Department of Agriculture and Consumer Services, along with information obtained from the South and Southwest Florida Water Management Districts consumptive water-use permits. Delineations were field verified between April and December 2016. Attribute data such as crop type, primary water source, and type of irrigation system were assigned to the irrigated areas.The results of this inventory and field verification indicate that during the 2016 growing seasons (spring, summer, fall, and winter), an estimated 88,652 acres were irrigated within Polk County. Of the total field-verified crops, 83,995 acres were in citrus; 2,893 acres were in other non-citrus fruit crops (blueberries, grapes, peaches, and strawberries); 621 acres were in row crops (primarily beans and watermelons); 1,117 acres were in nursery (container and tree farms) and sod production; and 26 acres were in field crops including hay and pasture. Of the total inventoried irrigated acreage within Polk County, 98 percent (86,566 acres) was in the Southwest Florida Water Management District, and the remaining 2 percent (2,086 acres) was in the South Florida Water Management District.About 85,788 acres (96.8 percent of the acreage inventoried) were irrigated by a microirrigation system, including drip, bubblers, and

  9. The use of auxiliary devices during irrigation to increase the cleaning ability of a chelating agent

    Directory of Open Access Journals (Sweden)

    Marina Carvalho Prado

    2017-05-01

    Full Text Available Objectives This study investigated the cleaning ability of ultrasonically activated irrigation (UAI and a novel activation system with reciprocating motion (EC, EasyClean, Easy Equipamentos Odontológicos when used with a relatively new chelating agent (QMix, Dentsply. In addition, the effect of QMix solution when used for a shorter (1 minute and a longer application time (3 minutes was investigated. Materials and Methods Fifty permanent human teeth were prepared with K3 rotary system and 6% sodium hypochlorite. Samples were randomly assigned to five groups (n = 10 according to the final irrigation protocol: G1, negative control (distilled water; G2, positive control (QMix 1 minute; G3, QMix 1 minute/UAI; G4, QMix 1 minute/EC; G5, QMix 3 minutes. Subsequently the teeth were prepared and three photomicrographs were obtained in each root third of root walls, by scanning electron microscopy. Two blinded and pre-calibrated examiners evaluated the images using a four-category scoring system. Data were statistically analyzed using Kruskal-Wallis and Dunn tests (p < 0.05. Results There were differences among groups (p < 0.05. UAI showed better cleaning ability than EC (p < 0.05. There were improvements when QMix was used with auxiliary devices in comparison with conventional irrigation (p < 0.05. Conventional irrigation for 3 minutes presented significantly better results than its use for 1 minute (p < 0.05. Conclusions QMix should be used for 1 minute when it is used with UAI, since this final irrigation protocol showed the best performance and also allowed clinical optimization of this procedure.

  10. Column leaching experiments of a uranium ore by atomizing irrigation technique

    International Nuclear Information System (INIS)

    Zeng Yingying; Lei Zeyong; Chen Haihui

    2007-01-01

    Column leaching experiments ora uranium ore were made by atomizing irrigation technique. The leaching results are compared with the results obtained by spray irrigation and drip irrigation techniques respectively under the same conditions of column leaching experiments. The results show that the atomizing irrigation technique has more uniform solution distribution, higher leaching rate, shorter leaching period, and less ratio of liquid to solid. Consequently, the atomizing irrigation technique is suitable to the ore. (authors)

  11. Evaluation of best management practices under intensive irrigation using SWAT model

    OpenAIRE

    Dechmi, Farida; Skhiri, Ahmed

    2013-01-01

    Land management practices such as conservation tillage and optimum irrigation are routinely used to reduce non-point source pollution and improve water quality. The calibrated and validated SWAT-IRRIG model is the first modified SWAT version that reproduces well the irrigation return flows (IRF) when the irrigation source is outside of the watershed. The application of this SWAT version in intensive irrigated systems permits to better evaluate the best management practices (BMPs) in such syst...

  12. Scheduling techniques in the Request Oriented Scheduling Engine (ROSE)

    Science.gov (United States)

    Zoch, David R.

    1991-01-01

    Scheduling techniques in the ROSE are presented in the form of the viewgraphs. The following subject areas are covered: agenda; ROSE summary and history; NCC-ROSE task goals; accomplishments; ROSE timeline manager; scheduling concerns; current and ROSE approaches; initial scheduling; BFSSE overview and example; and summary.

  13. Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

    OpenAIRE

    Williams, N S; Johnston, D

    1980-01-01

    Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complicati...

  14. Soil Suitability Classification of Tomas Irrigation Scheme for Irrigated ...

    African Journals Online (AJOL)

    The need for sustainable rice production in Nigeria cannot be over-emphasized. Since rice can be grown both under rain-fed and irrigated conditions, the need for soil suitability evaluation becomes very necessary in order for supply to meet up with demand. Six land qualities viz; climate, soil physical properties, drainage, ...

  15. Solar-thermal jet pumping for irrigation

    Science.gov (United States)

    Clements, L. D.; Dellenback, P. A.; Bell, C. A.

    1980-01-01

    This paper describes a novel concept in solar powered irrigation pumping, gives measured performance data for the pump unit, and projected system performance. The solar-thermal jet pumping concept is centered around a conventional jet eductor pump which is commercially available at low cost. The jet eductor pump is powered by moderate temperature, moderate pressure Refrigerant-113 vapor supplied by a concentrating solar collector field. The R-113 vapor is direct condensed by the produced water and the two fluids are separated at the surface. The water goes on to use and the R-113 is repressurized and returned to the solar field. The key issue in the solar-thermal jet eductor concept is the efficiency of pump operation. Performance data from a small scale experimental unit which utilizes an electrically heated boiler in place of the solar field is presented. The solar-thermal jet eductor concept is compared with other solar irrigation concepts and optimal application situations are identified. Though having lower efficiencies than existing Rankine cycle solar-thermal irrigation systems, the mechanical and operational simplicity of this concept make it competitive with other solar powered irrigation schemes.

  16. Grey mould development in greenhouse tomatoes under drip and furrow irrigation

    OpenAIRE

    Aissat , Kamel; Nicot , Philippe ,; Guechi , Abdelhadi; Bardin , Marc; Chibane , Mohamed

    2008-01-01

    Several methods can be used to provide water to plants in cropping systems where irrigation is necessary. For instance, drip irrigation has recently received much attention due to its advantages for water conservation. The type of irrigation can also impact the development of several pathogens responsible for soilborne diseases. Here, we studied the effect of drip irrigation and furrow irrigation on the development of grey mould, caused by the airborne fungus Botrytis cinerea, on tomato plant...

  17. Using Automation to Improve Surface Irrigation Management

    Science.gov (United States)

    In the Lower Mississippi Water Resource Area (WRA 08), also called the Mid-South, 2 million ha of cropland (80% of the irrigated farmland) employ surface irrigation, almost equally divided between furrow (52%) and controlled flooding (48%). Because Mid-South farmers experience less-than-optimal surf...

  18. Technical efficiency of irrigated vegetable production among ...

    African Journals Online (AJOL)

    This study was carried out to analyse the technical efficiency of irrigated vegetable production among smallholder farmers in the guinea savannah, Nigeria, and determine the cost and returns on irrigated vegetable production. Two-stage sampling technique was used, purposive selection of two states and three Local ...

  19. Stakeholder analysis in the management of irrigation in Kampili area

    Science.gov (United States)

    Jumiati; Ali, M. S. S.; Fahmid, I. M.; Mahyuddin

    2018-05-01

    Irrigation has appreciable contribution in building food security, particularly rice crops. This study aims to analyze the role of stakeholders involved in distributing of irrigation water. The study was conducted in the Kampili Irrigation Area in South Sulawesi Province Indonesia, the data were obtained through observation and interviews with stakeholders involved, and analysed by stakeholder analysis, based on the interests and power held by the actors. This analysis is intended to provide an optimal picture of the expected role of each stakeholder in the management of irrigation resources. The results show that there were many stakeholders involved in irrigation management. In the arrangement of irrigation distribution there was overlapping authority of the stakeholders to its management, every stakeholder had different interests and power between each other. The existence have given positive and negative values in distributing irrigation water management, then in the stakeholder collaboration there was contestation between them. This contestation took place between the agriculture department, PSDA province, the Jeneberang River Region Hall, the Farmers Group and the P3A.

  20. Research advances on thereasonable water resources allocation in irrigation district

    DEFF Research Database (Denmark)

    Xuebin, Qi; Zhongdong, Huang; Dongmei, Qiao

    2015-01-01

    The rational allocation of water resources for irrigation is important to improve the efficiency in utilization of water resources and ensuring food security, but also effective control measures need to be in place for the sustainable utilization of water resources in an irrigation area. The prog......The rational allocation of water resources for irrigation is important to improve the efficiency in utilization of water resources and ensuring food security, but also effective control measures need to be in place for the sustainable utilization of water resources in an irrigation area...... mechanism of water resources is not perfect, the model for optimal water resources allocation is not practical, and the basic conditions for optimal allocation of water resources is relatively weak. In order to solve those problems in water resources allocation practice, six important as?pects must...... in irrigation districts, studying the water resources control technology in irrigation districts by hydrology ecological system, studying the technologies of real?time risk dispatching and intelligent management in irrigation districts, and finally studying the technology of cou?pling optimal allocation...

  1. The Effect of Different Levels of Irrigation and Nitrogen Fertilizer on Yield and Water Use Efficiency of Potato in Subsurface Drip Irrigation

    Directory of Open Access Journals (Sweden)

    Mohammad Jolaini

    2017-06-01

    Full Text Available Introduction: After wheat, rice and corn, potato is the fourth most important food plant in the world. In comparison with other species, potato is very sensitive to water stress because of its shallow root system: approximately 85% of the root length is concentrated in the upper 0.3-0.4 m of the soil. Several studies showed that drip irrigation is an effective method for enhancing potato yield. Fabeiro et al. (2001 concluded that tuber bulking and ripening stages were found to be the most sensitive stages of water stress with drip irrigation. Water deficit occurring in these two growth stages could result in yield reductions. Wang et al. (2006 investigated the effects of drip irrigation frequency on soil wetting pattern and potato yield. The results indicated that potato roots were not limited in wetted soil volume even when the crop was irrigated at the highest frequency while high frequency irrigation enhanced potato tuber growth and water use efficiency (WUE. Though information about irrigation and N management of this crop is often conflicting in the literature, it is accepted generally that production and quality are highly influenced by both N and irrigation amounts and these requirements are related to the cropping technique. Researches revealed that nitrogen fertilizers play a special role in the growth, production and quality of potatoes. Materials and Methods: A factorial experiment in randomized complete block design with three replications was carried out during two growing seasons. Studied factors were irrigation frequency (I1:2 and I2:4 days interval and nitrogen fertilizer levels (applying 100 (N1, 75 (N2 and 50 (N3 % of the recommended amount. Nitrogen fertilizer was applied through irrigation water. In each plot two rows with within-and between-row spacing of 45 and 105 cm and 20 m length. The amount of nitrogen fertilizer for the control treatment was determined by soil analysis (N1. In all treatments, nitrogen fertilizer

  2. Effects of different deficit irrigation on sugar accumulation of pineapple during development

    Science.gov (United States)

    Feng, Haiyan; Du, Liqing; Liu, Shenghui; Zhang, Xiumei

    2017-08-01

    The potted pineapple cultivar ‘Comte de paris’ was used to study the influence of deficit irrigation on fruit sugar accumulation in greenhouse during the fruit enlargement period. The study included a control (normal irrigation) and two treatment groups, moderate deficit (50% of the control irrigation) and severe deficit (25% of the control irrigation). The results indicated that the deficit irrigation significantly decreased the sucrose accumulation. The sucrose content in the fruits of moderate deficit irrigation was the lowest. During the mature period, the deficit irrigation decreased the sucrose phosophate synthase activity(SPS) an increased the sucrose synthase (SS) and neutral invertase (NI). The moderate deficit irrigation significantly improved the acid invertase activity(AI). However, it was inhibited by the severe deficit irrigation. In general, the moderate treatment reduced the SPS activity and enhanced the NI and AI activities, while the severe treatment decreased the SPS and AI activities.

  3. The management perspective on the performance of the irrigation subsector

    OpenAIRE

    Nijman, C.

    1993-01-01

    INVESTMENT IN IRRIGATION has been immense in the past. Estimated average annual investments of US$ 15 billion makes irrigation the largest subsector of the agricultural sector, that is itself by far the largest sector of development investment. Since the mid-1960s the awareness spread that the performance of irrigation investments was far below its potential. The size of this underperformance is well represented by Seckler's alarming conclusion that the average irrigation investment costs twi...

  4. Is the Revitalisation of Smallholder Irrigation Schemes (RESIS ...

    African Journals Online (AJOL)

    2013-09-30

    Sep 30, 2013 ... including rainwater harvesting, flood recession, flood water spreading, river ... Smallholder irrigation systems can comprise farmers who use shared or ...... on Irrigation and Drainage, 15-17 November 2006, Aventura. Swadini.

  5. Irrigation-water quality during 1976 irrigation season in the Sulphur Creek basin, Yakima and Benton counties, Washington

    Science.gov (United States)

    Boucher, P.R.; Fretwell, M.O.

    1982-01-01

    A water-quality-sampling network was designed for the Sulphur Creek basin to observe the effects of farming practices on irrigation. Sediment and nutrient yield, discharge, and water temperature data were collected during the 1976 irrigation season and the following fall and winter. The suspended-sediment yield of the basin during this period was 2.0 tons per acre of irrigated cropland. Only about 3% of the net outflow of sediment occurred during the nonirrigation season. The yield computed by subbasin ranged from 0.7 to 7 tons per acre, depending mainly on land slope, but a high percentage of orchard land in the subbasins was probably also significant in reducing loads. Nutrient outflows during the study period were 1,180,000 pounds of nitrogen and 120,000 pounds of phosphorous. Nitrate-plus-nitrite represent 70% of the nitrogen outflow in the irrigation season and 84% in the nonirrigation season. The monitoring network was discontinued at the end of the study period, due largely to insufficient farmer participation. Network sensitivity in the control subbasins was inadequate to detect the effects of a planned demonstration program of best management practices. (USGS)

  6. Estimation of furrow irrigation sediment loss using an artificial neural network

    Science.gov (United States)

    The area irrigated by furrow irrigation in the U.S. has been steadily decreasing but still represents about 20% of the total irrigated area in the U.S. Furrow irrigation sediment loss is a major water quality issue and a method for estimating sediment loss is needed to quantify the environmental imp...

  7. Irrigation method does not affect wild bee pollinators of hybrid sunflower

    Directory of Open Access Journals (Sweden)

    Hillary Sardiñas

    2016-09-01

    Full Text Available Irrigation method has the potential to directly or indirectly influence populations of wild bee crop pollinators nesting and foraging in irrigated crop fields. The majority of wild bee species nest in the ground, and their nests may be susceptible to flooding. In addition, their pollination of crops can be influenced by nectar quality and quantity, which are related to water availability. To determine whether different irrigation methods affect crop pollinators, we compared the number of ground-nesting bees nesting and foraging in drip- and furrow-irrigated hybrid sunflower fields in the Sacramento Valley. We found that irrigation method did not impact wild bee nesting rates or foraging bee abundance or bee species richness. These findings suggest that changing from furrow irrigation to drip irrigation to conserve water likely will not alter hybrid sunflower crop pollination.

  8. Assessing the groundwater recharge under various irrigation schemes in Central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Lin, Zih-Ciao; Tsai, Cheng-Bin

    2014-05-01

    The flooded paddy fields can be considered as a major source of groundwater recharge in Central Taiwan. The risk of rice production has increased notably due to climate change in this area. To respond to agricultural water shortage caused by climate change without affecting rice yield in the future, the application of water-saving irrigation is the substantial resolution. The System of Rice Intensification (SRI) was developed as a set of insights and practices used in growing irrigated rice. Based on the water-saving irrigation practice of SRI, impacts of the new methodology on the reducing of groundwater recharge were assessed in central Taiwan. The three-dimensional finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge under different irrigation schemes. According to local climatic and environmental characteristics associated with SRI methodology, the change of infiltration rate was evaluated and compared with the traditional irrigation schemes, including continuous irrigation and rotational irrigation scheme. The simulation results showed that the average infiltration rate in the rice growing season decreased when applying the SRI methodology, and the total groundwater recharge amount of SRI with a 5-day irrigation interval reduced 12% and 9% compared with continuous irrigation (6cm constant ponding water depth) and rotational scheme (5-day irrigation interval with 6 cm initial ponding water depth), respectively. The results could be used as basis for planning long-term adaptive water resource management strategies to climate change in Central Taiwan. Keywords: SRI, Irrigation schemes, Groundwater recharge, Infiltration

  9. Prospects and Constraints of Household Irrigation Practices ...

    African Journals Online (AJOL)

    Constraints and prospects of hand dug wells related to household irrigation were assessed in Hayelom watershed (~1045 ha), by evaluating groundwater suitability for irrigation, soil quality and impact of intervention. 181 hand dug wells have come into existence in the watershed due to intervention and benefiting about ...

  10. Participatory Irrigation Management and Irrigation Water Use Efficiency in Maize Production: Evidence from Zhangye City, Northwestern China

    Directory of Open Access Journals (Sweden)

    Qing Zhou

    2017-10-01

    Full Text Available Water has become increasingly scarce in northwestern China due to climate change, economic growth and burgeoning population. Improving agriculture water use efficiency is of strategic significance in promoting socio-economic water productivity for arid and semi-arid inland river basins. Based on the household-level data collected in Zhangye City, which is located in the middle reaches of Heihe River Basin (HRB in northwestern China, irrigation water use efficiency (IWUE of maize is estimated based on stochastic frontier analysis. The impacts of influential factors, especially the participatory irrigation management (PIM through water user associations (WUAs, on IWUE were further examined. Results show that the estimated average Technical efficiency (TE and IWUE of maize production are 0.74 and 0.24, respectively. The participation level in irrigation management is very low, with only 40% of the respondents participating in WUA meetings. In addition, most have a relatively superficial understanding of the roles and management scheme of WUAs. Empirical results show that though significantly positive, the magnitude of the impact of PIM on IWUE is relatively small. Households that participated in WUA meetings achieved only 0.002% higher IWUEs than those have never participated in. WUAs are not operating with their designed objectives. Consequently, reform of the traditional management form of WUAs to make them more transparent, fair, and extensively participated in among farmers is in urgently need. In addition, we also find that water price, source of irrigation water, irrigation technology adoption and famers’ education level and farming experience also have significant positive impacts on IWUE.

  11. Limited irrigation research and infrared thermometry for detecting water stress

    Science.gov (United States)

    The USDA-ARS Limited Irrigation Research Farm, located outside of Greeley Colorado, is an experiment evaluating management perspectives of limited irrigation water. An overview of the farm systems is shown, including drip irrigation systems, water budgeting, and experimental design, as well as preli...

  12. Infrared thermometry to schedule irrigation of common bean Termometria ao infravermelho na programação da irrigação de feijoeiro

    Directory of Open Access Journals (Sweden)

    Francisco de Almeida Lobo

    2004-02-01

    Full Text Available The objective of this work was to determine the critical irrigation time for common bean (Phaseolus vulgaris L. cv. Carioca using infrared thermometry. Five treatments were analyzed. Canopy temperature differences between plants and a well-watered control about 1, 2, 3, 4, and 5±0.5ºC were tested. Physiological variables and plant growth were analyzed to establish the best time to irrigate. There was a significant linear correlation between the index and stomatal resistance, transpiration rate, and leaf water potential. Although significant linear correlation between the index and mean values of total dry matter, absolute growth rate, and leaf area index was found, no correlation was found with other growth index like relative growth rate, net assimilation rate, and leaf area ratio. Plants irrigated when their canopy temperature was 3±0.5ºC above the control had their relative growth rate mean value increased up to 59.7%, yielding 2,260.2 kg ha-1, with a reduction of 38.0% in the amount of water used. Plants irrigated when their canopy temperature was 4±0.5ºC yielded 1,907.6 kg ha-1, although their relative growth rate mean value was 4.0% below the control. These results show that the best moment to irrigate common bean is when their canopy temperature is between 3ºC and 4±0.5ºC above the control.O objetivo deste trabalho foi determinar o momento crítico para efetuar a irrigação do feijoeiro (Phaseolus vulgaris L. cv. Carioca utilizando a termometria ao infravermelho. Foram analisados cinco tratamentos. As diferenças entre a temperatura foliar das plantas e a de um controle mantido bem irrigado testadas foram de 1, 2, 3, 4 e 5±0,5ºC. Foram analisadas variáveis fisiológicas e de crescimento para identificar o melhor momento de irrigação. Encontrou-se uma correlação linear significativa entre o índice empregado e a resistência estomática, a taxa transpiratória e o potencial hídrico foliar. Embora tenha-se verificado uma

  13. Costs and benefits of satellite-based tools for irrigation management

    Directory of Open Access Journals (Sweden)

    Francesco eVuolo

    2015-07-01

    Full Text Available This paper presents the results of a collaborative work with farmers and a cost-benefit analysis of geospatial technologies applied to irrigation water management in the semi-arid agricultural area in Lower Austria. We use Earth observation (EO data to estimate crop evapotranspiration (ET and webGIS technologies to deliver maps and irrigation advice to farmers. The study reports the technical and qualitative evaluation performed during a demonstration phase in 2013 and provides an outlook to future developments. The calculation of the benefits is based on a comparison of the irrigation volumes estimated from satellite vs. the irrigation supplied by the farmers. In most cases, the amount of water supplied was equal to the maximum amount of water required by crops. At the same time high variability was observed for the different irrigation units and crop types. Our data clearly indicates that economic benefits could be achieved by reducing irrigation volumes, especially for water-intensive crops. Regarding the qualitative evaluation, most of the farmers expressed a very positive interest in the provided information. In particular, information related to crop ET was appreciated as this helps to make better informed decisions on irrigation. The majority of farmers (54% also expressed a general willingness to pay, either directly or via cost sharing, for such a service. Based on different cost scenarios, we calculated the cost of the service. Considering 20,000 ha regularly irrigated land, the advisory service would cost between 2.5 and 4.3 €/ha per year depending on the type of satellite data used. For comparison, irrigation costs range between 400 and 1000 €/ha per year for a typical irrigation volume of 2,000 cubic meters per ha. With a correct irrigation application, more than 10% of the water and energy could be saved in water-intensive crops, which is equivalent to an economic benefit of 40-100 €/ha per year.

  14. Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation.

    Science.gov (United States)

    Colangelo, D J; Brand, M H

    2001-01-01

    Container production of nursery crops is intensive and a potential source of nitrogen release to the environment. This study was conducted to determine if trickle irrigation could be used by container nursery producers as an alternative to standard overhead irrigation to reduce nitrogen release into the environment. The effect of overhead irrigation and trickle irrigation on leachate nitrate N concentration, flow-weighted nitrate N concentration, leachate volume, and plant growth was investigated using containerized rhododendron (Rhododendron catawbiense Michx. 'Album') supplied with a controlled-release fertilizer and grown outdoors on top of soil-monolith lysimeters. Leachate was collected over two growing seasons and overwinter periods, and natural precipitation was allowed as a component of the system. Precipitation accounted for 69% of the water entering the overhead-irrigated system and 80% of the water entering the trickle-irrigated system. Leachate from fertilized plants exceeded the USEPA limit of 10 mg L(-1) at several times and reached a maximum of 26 mg L(-1) with trickle irrigation. Average annual loss of nitrate N in leachate for fertilized treatments was 51.8 and 60.5 kg ha(-1) for the overhead and trickle treatments, respectively. Average annual flow-weighted concentration of nitrate N in leachate of fertilized plants was 7.2 mg L(-1) for overhead irrigation and 12.7 mg L(-1) for trickle irrigation. Trickle irrigation did not reduce the amount of nitrate N leached from nursery containers when compared with overhead irrigation because precipitation nullified the potential benefits of reduced leaching fractions and irrigation inputs provided under trickle irrigation.

  15. Design and implementation of expert decision system in Yellow River Irrigation

    Science.gov (United States)

    Fuping, Wang; Bingbing, Lei; Jie, Pan

    2018-03-01

    How to make full use of water resources in the Yellow River irrigation is a problem needed to be solved urgently. On account of the different irrigation strategies in various growth stages of wheat, this paper proposes a novel irrigation expert decision system basing on fuzzy control technique. According to the control experience, expert knowledge and MATLAB simulation optimization, we obtain the irrigation fuzzy control table stored in the computer memory. The controlling irrigation is accomplished by reading the data from fuzzy control table. The experimental results show that the expert system can be used in the production of wheat to achieve timely and appropriate irrigation, and ensure that wheat growth cycle is always in the best growth environment.

  16. 2007 Wholesale Power Rate Schedules : 2007 General Rate Schedule Provisions.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2006-11-01

    This schedule is available for the contract purchase of Firm Power to be used within the Pacific Northwest (PNW). Priority Firm (PF) Power may be purchased by public bodies, cooperatives, and Federal agencies for resale to ultimate consumers, for direct consumption, and for Construction, Test and Start-Up, and Station Service. Rates in this schedule are in effect beginning October 1, 2006, and apply to purchases under requirements Firm Power sales contracts for a three-year period. The Slice Product is only available for public bodies and cooperatives who have signed Slice contracts for the FY 2002-2011 period. Utilities participating in the Residential Exchange Program (REP) under Section 5(c) of the Northwest Power Act may purchase Priority Firm Power pursuant to the Residential Exchange Program. Rates under contracts that contain charges that escalate based on BPA's Priority Firm Power rates shall be based on the three-year rates listed in this rate schedule in addition to applicable transmission charges. This rate schedule supersedes the PF-02 rate schedule, which went into effect October 1, 2001. Sales under the PF-07 rate schedule are subject to BPA's 2007 General Rate Schedule Provisions (2007 GRSPs). Products available under this rate schedule are defined in the 2007 GRSPs. For sales under this rate schedule, bills shall be rendered and payments due pursuant to BPA's 2007 GRSPs and billing process.

  17. Energy savings potential from energy-conserving irrigation systems

    Energy Technology Data Exchange (ETDEWEB)

    Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

    1982-11-01

    This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

  18. Continuity-Aware Scheduling Algorithm for Scalable Video Streaming

    Directory of Open Access Journals (Sweden)

    Atinat Palawan

    2016-05-01

    Full Text Available The consumer demand for retrieving and delivering visual content through consumer electronic devices has increased rapidly in recent years. The quality of video in packet networks is susceptible to certain traffic characteristics: average bandwidth availability, loss, delay and delay variation (jitter. This paper presents a scheduling algorithm that modifies the stream of scalable video to combat jitter. The algorithm provides unequal look-ahead by safeguarding the base layer (without the need for overhead of the scalable video. The results of the experiments show that our scheduling algorithm reduces the number of frames with a violated deadline and significantly improves the continuity of the video stream without compromising the average Y Peek Signal-to-Noise Ratio (PSNR.

  19. 77 FR 37443 - Records Schedules; Availability and Request for Comments

    Science.gov (United States)

    2012-06-21

    ... an electronic information system used to track review action assignments and customer satisfaction... disposal or reduce the retention period of records already authorized for disposal. NARA invites public... accumulation, agency records managers prepare schedules proposing retention periods for records and submit...

  20. Project management with dynamic scheduling baseline scheduling, risk analysis and project control

    CERN Document Server

    Vanhoucke, Mario

    2013-01-01

    The topic of this book is known as dynamic scheduling, and is used to refer to three dimensions of project management and scheduling: the construction of a baseline schedule and the analysis of a project schedule's risk as preparation of the project control phase during project progress. This dynamic scheduling point of view implicitly assumes that the usability of a project's baseline schedule is rather limited and only acts as a point of reference in the project life cycle.

  1. Municipal Treated Wastewater Irrigation: Microbiological Risk Evaluation

    Directory of Open Access Journals (Sweden)

    Antonio Lonigro

    2008-06-01

    Full Text Available Municipal wastewater for irrigation, though treated, can contain substances and pathogens toxic for humans and animals. Pathogens, although not harmful from an agronomical aspect, undoubtedly represent a major concern with regards to sanitary and hygienic profile. In fact, vegetable crops irrigated with treated wastewater exalt the risk of infection since these products can also be eaten raw, as well as transformed or cooked. Practically, the evaluation of the microbiological risk is important to verify if the microbial limits imposed by law for treated municipal wastewater for irrigation, are valid, thus justifying the treatments costs, or if they are too low and, therefore, they don’ t justify them. Different probabilistic models have been studied to assess the microbiological risk; among these, the Beta-Poisson model resulted the most reliable. Thus, the Dipartimento di Scienze delle Produzioni Vegetali of the University of Bari, which has been carrying out researches on irrigation with municipal filtered wastewater for several years, considered interesting to verify if the microbial limits imposed by the italian law n.185/03 are too severe, estimating the biological risk by the probabilistic Beta-Poisson model. Results of field trials on vegetable crops irrigated by municipal filtered wastewater, processed by the Beta-Poisson model, show that the probability to get infection and/or illness is extremely low, and that the actual italian microbial limits are excessively restrictive.

  2. The Power to Resist: Irrigation Management Transfer in Indonesia

    Directory of Open Access Journals (Sweden)

    Diana Suhardiman

    2013-02-01

    Full Text Available In the last two decades, international donors have promoted Irrigation Management Transfer (IMT as an international remedy to management problems in government irrigation systems in many developing countries. This article analyses the political processes that shape IMT policy formulation and implementation in Indonesia. It links IMT with the issue of bureaucratic reform and argues that its potential to address current problems in government irrigation systems cannot be achieved if the irrigation agency is not convinced about the need for management transfer. IMT’s significance cannot be measured only through IMT outcomes and impacts, without linking these with how the irrigation agency perceives the idea of management transfer in the first place, how this perception (redefines the agency’s position in IMT, and how it shapes the agency’s action and strategy in the policy formulation and implementation. I illustrate how the irrigation agency contested the idea of management transfer by referring to IMT policy adoption in 1987 and its renewal in 1999. The article concludes that for management transfer to be meaningful it is pertinent that the issue of bureaucratic reform is incorporated into current policy discussions.

  3. NASA scheduling technologies

    Science.gov (United States)

    Adair, Jerry R.

    1994-01-01

    This paper is a consolidated report on ten major planning and scheduling systems that have been developed by the National Aeronautics and Space Administration (NASA). A description of each system, its components, and how it could be potentially used in private industry is provided in this paper. The planning and scheduling technology represented by the systems ranges from activity based scheduling employing artificial intelligence (AI) techniques to constraint based, iterative repair scheduling. The space related application domains in which the systems have been deployed vary from Space Shuttle monitoring during launch countdown to long term Hubble Space Telescope (HST) scheduling. This paper also describes any correlation that may exist between the work done on different planning and scheduling systems. Finally, this paper documents the lessons learned from the work and research performed in planning and scheduling technology and describes the areas where future work will be conducted.

  4. 75 FR 42831 - Proposed Collection; Comment Request for Form 1065, Schedule C, Schedule D, Schedule K-1...

    Science.gov (United States)

    2010-07-22

    .../or continuing information collections, as required by the Paperwork Reduction Act of 1995, Public Law... Income, Credits, Deductions and Other Items), Schedule L (Balance Sheets per Books), Schedule M-1 (Reconciliation of Income (Loss) per Books With Income (Loss) per Return)), Schedule M-2 (Analysis of Partners...

  5. The impact of smallholder irrigation on household welfare: The case ...

    African Journals Online (AJOL)

    The potential of smallholder irrigated agriculture to enhance food security and alleviate rural poverty has led the South African Government to prioritise and invest significantly in irrigation establishment, rehabilitation and revitalisation. The question addressed in this study pertains to the extent to which smallholder irrigation ...

  6. Tracking antibiotic resistance genes in soil irrigated with dairy wastewater

    Science.gov (United States)

    In southern Idaho, the application of dairy wastewater to agricultural soils is a widely used practice to irrigate crops and recycle nutrients. In this study, small-scale field plots were irrigated monthly (6 times) with dairy wastewater (100%), wastewater diluted to 50% with irrigation (canal) wate...

  7. Irrigation water quality as indicator of sustainable rural development

    Directory of Open Access Journals (Sweden)

    Trajković Slaviša

    2004-01-01

    Full Text Available The sustainable rural development more and more depends on the efficient usage of water resources. Most often, at least in one part of the year, the rain is not sufficient for plant growth and rain plant production significantly depends on the yearly precipitation variation. The increase and stability of the agricultural production is possible in the irrigation conditions. The most part (around 70% of the global water resources is used for food production. Irrigation water quality indicator is used to show if the available water resources have the required quality for application in agriculture. Irrigation is characterised by the complex water-plant-soil relationship, and in that eco-system the man as the end user of the irrigated fields occupies a very important place. That explains the difficulties in producing one universal classification of irrigation water quality. The paper analyses numerous water quality classifications from the aspect of the applicability on the quantifying of this indicator. The adopted classification should possess understandable, qualified and internationally comparable indicator. Thus, local classifications (Neigebauer, Miljkovic cannot be used for this indicator. United Nation Food and Agricultural Organization (FAO and US Salinity Laboratory (USSL classifications are used for the evaluation of the irrigation water quality throughout the world. FAO classification gives the complex picture of the usability of the irrigation water from the point of its influence on the soil and the plants. However, the scope of the analyses is not often suited to the needs of that classification, which makes it difficult to apply. The conclusion is that the USSL (US Salinity Laboratory classification is best suited to this range of chemical water analyses. The evaluation of the irrigation water quality indicator in the Juzna Morava river basin, upstream from the Toplica river estuary is given in this paper. Based on the obtained

  8. Bureaucratic Reform in Irrigation: A Review of Four Case Studies

    Directory of Open Access Journals (Sweden)

    Diana Suhardiman

    2014-10-01

    Full Text Available Poor performance of government-managed irrigation systems persists globally. This paper argues that addressing performance requires not simply more investment or different policy approaches, but reform of the bureaucracies responsible for irrigation management. Based on reform experiences in The Philippines, Mexico, Indonesia, and Uzbekistan, we argue that irrigation (policy reform cannot be treated in isolation from the overall functioning of government bureaucracies and the wider political structure of the states. Understanding of how and why government bureaucracies shape reform processes and outcomes is crucial to increase the actual significance of reforms. To demonstrate this, the paper links reform processes in the irrigation sector with the wider discourse of bureaucratic reform in the political science, public administration, and organisational science literature. Doing so brings to light the need for systematic comparative research on the organisational characteristic of the irrigation bureaucracies, their bureaucratic identities, and how these are shaped by various segments within the bureaucracies to provide the insights needed to improve irrigation systems performance.

  9. Mapping the rainfall distribution for irrigation planning in dry season at pineapple plantation, Lampung Province, Indonesia (Study case at Great Giant Pineapple Co. Ltd.)

    Science.gov (United States)

    Cahyono, P.; Astuti, N. K.; Purwito; Rahmat, A.

    2018-03-01

    One of the problems caused by climate change is unpredictable of the dry season. Understanding when the dry season will start is very important to planning the irrigation schedule especially on large plantation. Data of rainfall for 30 years in Lampung, especially in Pineapple Plantation show that dry month occurs from June to October. If in two decadals (ten days period) rainfall less than 100 mm then it is predicted that next decadal will be dry season. Great Giant Pineapple Co. Ltd. has 32,000 hectares plantation area and located in three regencies at Lampung Province, Indonesia with varies rainfall between regions within a plantation. Therefore, monitoring the rainfall distribution by using ombrometer installed at 10 representative location points can be used to determine irrigation period at the beginning of dry season. Mapping method using the server program and data source is from 10 monitoring rainfall stations installed at the observed points. Preparation of rainfall distribution mapping is important to know the beginning of the dry season and thus planning the irrigation. The results show that 2nd decadal of April is indicated as the starting time of dry season, which is similar with Indonesian government for climate agency’s result.

  10. Participatory management reforms in irrigation sector of sindh

    International Nuclear Information System (INIS)

    Lashari, B.K.

    2009-01-01

    Pakistan has been making efforts to restructuring the century old irrigation system by involving beneficiaries (water users) at various units of the irrigation system management. The main purposes of reforms are to improve O and M (Operation and Maintenance) of irrigation system, to make balance in expenditure and revenue, to improve crop production through efficient use of water, to maintain affordable drainage system and to adopt PWRM (Participatory Water Resource Management) approach. In these reforms, the Sindh provincial irrigation department was transferred to an autonomous body as SmA (Sindh Irrigation and Drainage Authority). Under SmA, CAWB (Canal Area Water Board) at each canal command area, water users association at watercourse level and Farmer Organizations at each secondary canal (Distributary/ Minor) command area were being formed. So far 335 FOs (Farmers Organizations) have been formed in Sindh. To evaluate the performance of FOs in their day to day activities such as water distribution, O and M of irrigation channels, conflict management and revenue (Abiana) collection, IMI (Institutional Maturity Index) of FOs is conducted. The objective IMI analysis was to assess the maturity of FOs in terms of organizational aspects, conflict resolution, financial aspects, water distribution, operation and maintenance, environmental aspects and capacity building of FOs. The IMI analyses identified the weaker aspects of the FOs and need of focus these aspects for improved performance of FOs through effective social mobilization and capacity building activities. (author)

  11. Influence of local topography on precision irrigation management

    Science.gov (United States)

    Precision irrigation management is currently accomplished using spatial information about soil properties through soil series maps or electrical conductivity (EC measurements. Crop yield, however, is consistently influenced by local topography, both in rain-fed and irrigated environments. Utilizing ...

  12. Soil and water management in spate irrigation systems in Eritrea

    NARCIS (Netherlands)

    Hadera, M.T.

    2001-01-01

    Spate irrigation has been practised over 100 years in the Red Sea coastal zone of Eritrea such as the Sheeb area. Main problem of the spate irrigation system is water shortage caused by irregular rainfall in the highlands of Eritrea and breaching of the irrigation structures by destructive

  13. Effects of seven different irrigation techniques on debris and the ...

    African Journals Online (AJOL)

    Aim: Conventional manual irrigation with a syringe and needle remains widely accepted technique in the irrigation procedures. However, its flushing action has some limitations. Currently, several techniques and systems are available and reported to improve the insufficiency of syringe irrigation. The aim of this study was to ...

  14. Analysis of Issues for Project Scheduling by Multiple, Dispersed Schedulers (distributed Scheduling) and Requirements for Manual Protocols and Computer-based Support

    Science.gov (United States)

    Richards, Stephen F.

    1991-01-01

    Although computerized operations have significant gains realized in many areas, one area, scheduling, has enjoyed few benefits from automation. The traditional methods of industrial engineering and operations research have not proven robust enough to handle the complexities associated with the scheduling of realistic problems. To address this need, NASA has developed the computer-aided scheduling system (COMPASS), a sophisticated, interactive scheduling tool that is in wide-spread use within NASA and the contractor community. Therefore, COMPASS provides no explicit support for the large class of problems in which several people, perhaps at various locations, build separate schedules that share a common pool of resources. This research examines the issue of distributing scheduling, as applied to application domains characterized by the partial ordering of tasks, limited resources, and time restrictions. The focus of this research is on identifying issues related to distributed scheduling, locating applicable problem domains within NASA, and suggesting areas for ongoing research. The issues that this research identifies are goals, rescheduling requirements, database support, the need for communication and coordination among individual schedulers, the potential for expert system support for scheduling, and the possibility of integrating artificially intelligent schedulers into a network of human schedulers.

  15. Preferential flow, nitrogen transformations and 15N balance under urine-affected areas of irrigated and non-irrigated clover-based pastures

    Science.gov (United States)

    Pakro, Naser; Dillon, Peter

    1995-12-01

    Urine-affected areas can lead to considerable losses of N by leaching, ammonia volatilisation and denitrification from dairy pastures in the southeast of South Australia. Potable groundwater supplies are considered to have become contaminated by nitrate as a result of leaching from these leguminous pastures. Dairy cow urine, labelled with 15N urea, was applied to micro-plots and mini-lysimeters installed in two adjacent irrigated (white clover-rye grass) and non-irrigated (subterranean clover-annual grasses) paddocks of a dairy farm on four occasions representing different seasonal conditions. These experiments allowed measurement of nitrogen transformations, recovery of 15N in the pasture and soil, and leaching below various depths. Gaseous losses were calculated from the nitrogen balance. The results of the four experiments showed that within a day of urine application up to 40% of the applied urinary-N was leached below a depth of 150 mm as a result of macropore flow in the irrigated paddock, and up to 24% in the non-irrigated one. After application to the irrigated paddock 17% of the urinary-N moved immediately below 300 mm but only 2% below the 450-mm depth. The urinary-N remaining in the soil was converted from urea to ammonium within a day regardless of season. Within the first 7 days of application six times more nitrate was produced in summer than in winter. This has obvious implications for leaching potential. Leaching of 15N from the top 150 mm of soil, following urine applications in all seasons, was between 41% and 62% of the applied 15N in the irrigated paddock and 25-51% in the non-irrigated paddock. However, leaching losses measured at depths of 300 or 450 mm were smaller by a factor of 2-4. The leaching loss of 15N applied in spring in both paddocks was 41% below 150 mm and 12% below 450 mm. Recovery of 15N from the soil-plant system in the 450-nm deep lysimeters was ˜60% of that applied. Estimated ammonia was ˜9% of applied 15N with no paddock

  16. Sensor-Based Model Driven Control Strategy for Precision Irrigation

    Directory of Open Access Journals (Sweden)

    Camilo Lozoya

    2016-01-01

    Full Text Available Improving the efficiency of the agricultural irrigation systems substantially contributes to sustainable water management. This improvement can be achieved through an automated irrigation system that includes a real-time control strategy based on the water, soil, and crop relationship. This paper presents a model driven control strategy applied to an irrigation system, in order to make an efficient use of water for large crop fields, that is, applying the correct amount of water in the correct place at the right moment. The proposed model uses a predictive algorithm that senses soil moisture and weather variables, to determine optimal amount of water required by the crop. This proposed approach is evaluated against a traditional irrigation system based on the empirical definition of time periods and against a basic soil moisture control system. Results indicate that the use of a model predictive control in an irrigation system achieves a higher efficiency and significantly reduce the water consumption.

  17. Response of potato to drip and gun irrigation systems

    DEFF Research Database (Denmark)

    Zhenjiang, Zhou; Andersen, Mathias Neumann; Plauborg, Finn

    2015-01-01

    The objective of this study was to evaluate effects of different irrigation and N fertilization regimes by gun irrigation and drip-fertigation on potato production, and subsequently optimize the supply of water and N fertilizer to the growth condition of the specific season and minimize nitrate......-fertigation system (DFdsNds) and two gun irrigation systems (GIdsN120 and GIaN120) to display the differences on growth, yield and water use efficiency of potato. All treatments were irrigated according to model simulated soil water content. For fertilization all treatments received a basic dressing at planting of P......, K, Mg and micronutrients, and in addition 120 kg N/ha in the gun irrigated treatments and 36 kg N/ha in the drip-fertigated. For the latter, portion of 20 kg N/ha was applied whenever plant N concentration approached a critical value as simulated by the Daisy model. As a result differences in soil...

  18. Effect of irrigation and stainless steel drills on dental implant bed heat generation.

    Science.gov (United States)

    Bullon, B; Bueno, E F; Herrero, M; Fernandez-Palacin, A; Rios, J V; Bullon, P; Gil, F J

    2015-02-01

    The objective of this study is assessing the influence of the use of different drill types and external irrigation on heat generation in the bone. In-vitro study to compare two different sequences for implant-bed preparation by means of two stainless steels: precipitation-hardening stainless steel (AISI 420B) (K drills), and martensitic stainless steel (AISI 440) (S drills). Besides, the drilled sequences were realized without irrigation, and with external irrigation by means of normal saline solution at room temperature. The study was realized on bovine ribs using: K without irrigation (KSI) and with irrigation (KCI) and S without irrigation (SSI) and with irrigation (SCI) with five drills for each system. Each drill was used 100 times. Bone temperature was measured with a thermocouple immediately after drilled. Average bone temperature with irrigation was for K drills 17.58±3.32 °C and for S drills 16.66±1.30 °C. Average bone temperature without irrigation was for K drills 23.58±2.94 °C and for S drills 19.41±2.27 °C. Statistically significant differences were found between K without irrigation versus S with irrigation and K with irrigation (pstainless steel AISI 420B presents better mechanical properties and corrosion resistance than AISI440.

  19. Greenhouse evaluation of deficit irrigation on the growth of tomato ...

    African Journals Online (AJOL)

    Deficit irrigation is considered to be an important approach for crop cultivation in dry regions where water resources are scarce. Deficit irrigation can be used also to decrease the level of infections by some moisturedependent plant pests and diseases such as root-knot nematode disease. Therefore, deficit irrigation at levels ...

  20. Critical parameters for maize yield under irrigation farming in the ...

    African Journals Online (AJOL)

    This study examines the critical variables that determine maize yield under irrigation farming in the savanna ecological zone of Kwara State. Seventy-five soil samples were randomly collected from irrigation farm of Oke-Oyi irrigation project of the Lower Niger River Basin Development Authority Ilorin and bulked into 15 ...

  1. Potentials for Supplemental Irrigation in Some Rainfall Areas of Imo ...

    African Journals Online (AJOL)

    In addition, there were up to five months of the year during which rainwater was much in deficit of evapotranspiration. All these stress the need for irrigation. Analysis of water quality (surface, groundwater, and rainfall runoff) showed their suitability for irrigation. Quantity assessment of supplemental irrigation during the dry ...

  2. Accelerating exact schedulability analysis for fixed-priority pre-emptive scheduling

    NARCIS (Netherlands)

    Hang, Y.; Jiale, Z.; Keskin, U.; Bril, R.J.

    2010-01-01

    The schedulability analysis for fixed-priority preemptive scheduling (FPPS) plays a significant role in the real-time systems domain. The so-called Hyperplanes Exact Test (HET) [1] is an example of an exact schedulability test for FPPS. In this paper, we aim at improving the efficiency of HET by

  3. Comparison of SVAT models for simulating and optimizing deficit irrigation systems in arid and semi-arid countries under climate variability

    Science.gov (United States)

    Kloss, Sebastian; Schuetze, Niels; Schmitz, Gerd H.

    2010-05-01

    The strong competition for fresh water in order to fulfill the increased demand for food worldwide has led to a renewed interest in techniques to improve water use efficiency (WUE) such as controlled deficit irrigation. Furthermore, as the implementation of crop models into complex decision support systems becomes more and more common, it is imperative to reliably predict the WUE as ratio of water consumption and yield. The objective of this paper is the assessment of the problems the crop models - such as FAO-33, DAISY, and APSIM in this study - face when maximizing the WUE. We applied these crop models for calculating the risk in yield reduction in view of different sources of uncertainty (e.g. climate) employing a stochastic framework for decision support for the planning of water supply in irrigation. The stochastic framework consists of: (i) a weather generator for simulating regional impacts of climate change; (ii) a new tailor-made evolutionary optimization algorithm for optimal irrigation scheduling with limited water supply; and (iii) the above mentioned models for simulating water transport and crop growth in a sound manner. The results present stochastic crop water production functions (SCWPF) for different crops which can be used as basic tools for assessing the impact of climate variability on the risk for the potential yield. Case studies from India, Oman, Malawi, and France are presented to assess the differences in modeling water stress and yield response for the different crop models.

  4. Evolution of Corn Transpiration and Leaf Water Potential During Sprinkler Irrigation

    OpenAIRE

    Martínez-Cob, Antonio; Fernández-Navajas, Julián; Durán, Víctor; Cavero Campo, José

    2009-01-01

    Corn (Zea mays L.) transpiration during daytime solid-set sprinkler irrigation was analyzed on two neighbouring subplots to determine the effect of the transpiration reduction on water application efficiency. During each irrigation event, one subplot was irrigated (moist treatment) while the other was not (dry treatment). Transpiration rates were determined at each subplot by the heat balance method (Dynamax Flow4 System) before, during and after the irrigations. During irri...

  5. Coupled Crop/Hydrology Model to Estimate Expanded Irrigation Impact on Water Resources

    Science.gov (United States)

    Handyside, C. T.; Cruise, J.

    2017-12-01

    A coupled agricultural and hydrologic systems model is used to examine the environmental impact of irrigation in the Southeast. A gridded crop model for the Southeast is used to determine regional irrigation demand. This irrigation demand is used in a regional hydrologic model to determine the hydrologic impact of irrigation. For the Southeast to maintain/expand irrigated agricultural production and provide adaptation to climate change and climate variability it will require integrated agricultural and hydrologic system models that can calculate irrigation demand and the impact of the this demand on the river hydrology. These integrated models can be used as (1) historical tools to examine vulnerability of expanded irrigation to past climate extremes (2) future tools to examine the sustainability of expanded irrigation under future climate scenarios and (3) a real-time tool to allow dynamic water resource management. Such tools are necessary to assure stakeholders and the public that irrigation can be carried out in a sustainable manner. The system tools to be discussed include a gridded version of the crop modeling system (DSSAT). The gridded model is referred to as GriDSSAT. The irrigation demand from GriDSSAT is coupled to a regional hydrologic model developed by the Eastern Forest Environmental Threat Assessment Center of the USDA Forest Service) (WaSSI). The crop model provides the dynamic irrigation demand which is a function of the weather. The hydrologic model includes all other competing uses of water. Examples of use the crop model coupled with the hydrologic model include historical analyses which show the change in hydrology as additional acres of irrigated land are added to water sheds. The first order change in hydrology is computed in terms of changes in the Water Availability Stress Index (WASSI) which is the ratio of water demand (irrigation, public water supply, industrial use, etc.) and water availability from the hydrologic model. Also

  6. Wastewater Use in Irrigated Agriculture : Confronting the Livelihood ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Wastewater Use in Irrigated Agriculture : Confronting the Livelihood and Environmental Realities. Couverture du livre Wastewater Use in Irrigated Agriculture: Confronting the Livelihood and Environmental Realities. Directeur(s) : Christopher Scott, Naser I. Faruqui et Liqa Raschid. Maison(s) d'édition : CABI, IWMI, CRDI.

  7. Effects of different irrigation methods on pepper yield and soilborne diseases incidence

    Directory of Open Access Journals (Sweden)

    Seral YÜCEL

    2013-12-01

    Full Text Available In this study, the effect of different irrigation strategies and irrigation methods on yields and the incidence of wilt (Fusarium oxysporum and root rot (Fusarium solani and Macrophomina phaseolina diseases causing significant yield losses on field grown processing red pepper is determined. Experiments were carried out at Topçu Station of the Soil and Water Resources Research Institute of Tarsus in 2010 and 2011. Karaisalı processing pepper (Capsicum annuum L. was used in the experiments. Three furrows and five drip irrigation treatments were used in the study. The disease incidence rates were found 8.0-18.2% in furrow irrigation plots and 4.5-10.0% in drip irrigation plots in 2010, while it was 3.4-9.7% in furrow irrigation plots and 2.2-4.5% in drip irrigation plots in 2011. Pepper yields ranged from 3 416 to 4 417 kg da-1 and 3 376 to 4 779 kg da-1 in drip irrigated plots in 2010 and 2011, respectively. However, yields varied between 3 172-3 559 kg da-1 and 2 932-4 150 kg da-1 in furrow irrigated plots in 2010 and 2011 growing seasons.

  8. Decadal Variation of Precipitation in Saudi Arabia induced by Agricultural Irrigation

    Science.gov (United States)

    Lo, M. H.; Wey, H. W.; Wada, Y.; IM, E. S.; Chien, R. Y.; Wu, R. J.

    2017-12-01

    Decadal variation of wet-season precipitation has been found in the arid region of central Saudi Arabia. 1980s has been a rather wet decade compared with the decades before. Previous studies have mentioned that the irrigation moisture may contribute to the precipitation anomalies in Saudi Arabia. In the current study, we show from observational data that the contribution of the variation comes mostly from February to May. As the irrigation is a localized forcing, we therefore use the Weather Research and Forecasting (WRF) Model to simulate the response of the land-atmosphere interaction to the wet soil moisture resulted from additional irrigation moisture supply. Preliminary result shows in the irrigated simulation that precipitation in central Saudi Arabia is enhanced, indicating the possible link between irrigation expansion in the 1980s and the decadal precipitation variation over central Saudi Arabia. We propose it is the anomalous convergence induced by irrigation as well as additional moisture that contribute to the enhanced precipitation over heavily irrigation region in the central Saudi Arabian. In addition, analysis on the daily precipitation from the WRF outputs indicates that positive rainfall anomalies tend to happen when there is rainfall originally; that is, irrigation enhances rainfall but not creates rainfall.

  9. Stoma management in a tropical country: colostomy irrigation versus natural evacuation.

    Science.gov (United States)

    Leong, A F; Yunos, A B

    1999-11-01

    People with ostomies in Singapore were initially resistant to colostomy irrigation. This study, a prospective crossover study of 26 patients who underwent abdominoperineal resection, compared colostomy irrigation with the natural evacuation method. During the colostomy-irrigation phase of the study, all 26 patients reported an improvement in continence and fewer problems with sleep, sex, and skin complications compared to the natural-evacuation phase. The study also found a reduction in monthly expenses with colostomy irrigation compared to natural evacuation. Patient satisfaction scores were also superior during the colostomy-irrigation phase. This difference in satisfaction scores was less marked in those who were more than 1-year postsurgery than in those who were less than 1-year postsurgery. The difference in satisfaction between colostomy irrigation and natural evacuation scores was statistically significant in the group that was less than 1-year postsurgery, but not in the group that was more than 1-year postsurgery. The study concluded that colostomy irrigation after abdominoperineal resection is superior to natural evacuation in terms of cost and patient satisfaction and should be introduced soon after surgery.

  10. Use of 15N methodology to assess urea use efficiency under different nitrogen levels in fertigation system and comparison with furrow irrigation on tomato

    International Nuclear Information System (INIS)

    Mousavi Shalmani, M. A.; Sagheb, N.; Hobbi, M.S.; Teimoori, S.; Khorasani, A.; Piervali, N.

    2003-01-01

    In order to determine a suitable level of nitrogen fertilizer for simultaneous increasing the nitrogen fertilizer use efficiency and the yield production under the trickle fertigation system in comparison with the furrow irrigation, an experimental design was conducted in a randomized complete block with five treatments and four replications in plots of 35 square meters area. The treatments of N 0 , N 1 , N 2 and N 3 received 0, 100, 150 and 200 mg N/lit, respectively under the trickle fertigation, and for the treatment of Ns the amount of fertilizer were equal to N 2 but under the furrow irrigation system. Fertilization and irrigation were performed by means of two fertigator pumps (one for urea and the other for ammonium phosphate and potassium sulfate) . In order to determine the nitrogen fertilizer use efficiency, six plants in the middle of each plot received 15 N labeled urea (isotopic form of 14 N) through plastic containers. Irrigation schedule and soil moisture monitoring were performed by means of a neutron gauge. The results showed that in spite of increasing the nitrogen levels in the fertigation system, the nitrogen fertilizer use efficiency decreases. In this respect, the treatment of N 1 could absorb %54 of nitrogen fertilizer which indicated that the highest fertilizer use efficiency under the current design condition and the final nitrogen fertilizer use efficiency for N 2 and N 3 treatments are %39 and %31, respectively. In addition, the traditional treatment (Ns), with %83 losses of nitrogen had the lowest rate of fertilizer use efficiency

  11. The comparison between two irrigation regimens on the dentine wettability for an epoxy resin based sealer by measuring its contact angle formed to the irrigated dentine.

    Science.gov (United States)

    Mohan, Rayapudi Phani; Pai, Annappa Raghavendra Vivekananda

    2015-01-01

    The aim was to assess the influence of two irrigation regimens having ethylenediaminetetraacetic acid (EDTA) and ethylenediaminetetraacetic acid with cetrimide (EDTAC) as final irrigants, respectively, on the dentine wettability for AH Plus sealer by comparing its contact angle formed to the irrigated dentine. Study samples were divided into two groups (n = 10). The groups were irrigated with 3% sodium hypochlorite (NaOCl) solution followed by either 17% EDTA or 17% EDTAC solution. AH Plus was mixed, and controlled volume droplet (0.1 mL) of the sealer was placed on the dried samples. The contact angle was measured using a Dynamic Contact Angle Analyzer and results were analyzed using SPSS 21.0 and 2 sample t-test. There was a significant difference in the contact angle of AH Plus formed to the dentine irrigated with the above two regimens. AH Plus showed significantly lower contact angle with the regimen having EDTAC as a final irrigant than the one with EDTA (P contact angle of a sealer. EDTAC as a final irrigant facilitates better dentin wettability than EDTA for AH Plus to promote its better flow and adhesion.

  12. Irrigation management of muskmelon with tensiometry

    Directory of Open Access Journals (Sweden)

    Márcio José de Santana

    2017-11-01

    Full Text Available The production and consumption of muskmelon have been increasing (MELO et al., 2014, thus, information on techniques for higher field productions are necessary. The experiment described in the present work was conducted in the IFTM, Uberaba, State of Minas Gerais, Brazil, aiming to evaluate the muskmelon yield under different soil water tensions. A randomized block experimental design was used with five treatments (soil water tensions of 10, 20, 30, 40 and 50 kPa and four replications (plots of two rows of 14 plants. Two harvests were carried out and the fruit yield, stem diameter, number of fruits per plant and efficiency of water use were evaluated. Irrigation was performed with a drip irrigation system and managed with tensiometry. The cultivar Bonus n.2 was used with spacing of 1.0 x 0.6 m. The data of the variables were subjected to the F test and regression test. The treatments showed statistical differences in number of fruits per plant, fruit weight (fruit yield and stem diameter. The highest fruit yield found was 1.36 kg fruit-1 and the highest water use efficiency was 4.08 g mm-1 with irrigation for a soil water tension of 10 kPa. The lowest fruit yield was found with irrigation for a soil water tension of 50 kPa.

  13. Irrigation and Rural Welfare: Implications of Schistosomiasis among ...

    African Journals Online (AJOL)

    This paper examines the effects of the prevalence of urinary schistosomiasis infection on the socio-economic health of irrigation farmers in the rural districts of Kazaure Area, Northern Nigeria. It first reviews some general consideration of irrigation environment and schistosomiasis, its major associated health problem.

  14. Aflaj’s Irrigation Water Demand/Supply Ratio: Two Case Studies

    Directory of Open Access Journals (Sweden)

    Abdullah Al-Ghafri

    2006-01-01

    Full Text Available Due to the geographical location of Oman in an arid zone, agricultural production depends fully on irrigation. The traditional irrigation systems (Aflaj, sing. falaj supply more than one third of water for agriculture. Falaj is defined in the context of this paper as a canal system which provides water for domestic and agricultural uses. Oman has 3,107 active Aflaj producing about 680 Mm3 of water per year. The main objective of this study was to estimate the irrigation performance of Aflaj in Oman. Falaj al-Dariz and al-Nujaid were chosen as case studies. Both Aflaj are located in an extremely arid environment, where the rainfall is low and evapotranspiration is high. The study utilized an approach to estimate the irrigation performance of Aflaj by considering the falaj as a single unit of irrigation. The irrigation demand/supply ratio (D/S was used in the analysis as a tool of evaluation. Date palm, the dominant crop irrigated by Aflaj, was selected for the analysis. In falaj al-Dariz the date palms were slightly under irrigated on a yearly basis. On a monthly basis, in winter, the D/S was below 0.6 and in summer it was above 1.0. On the other hand, falaj al-Nujaid was supplying too much water than the date palms needed all round the year. In winter the D/S ratio was as low as 0.25. Even in summer, the D/S ratio did not much exceed 1.0.

  15. Evaluation of reservoir operation strategies for irrigation in the Macul Basin, Ecuador

    Directory of Open Access Journals (Sweden)

    Vicente Tinoco

    2016-03-01

    Full Text Available Study focus: An irrigation project is planned in the study basin for developing the agriculture as the main income in the region. The proposed water system comprises three large reservoirs damming the rivers Macul and Maculillo. The river basin planning and operation were investigated by modelling alternative reservoir operation strategies aiming at a sustainable balance between irrigation and river ecology by integrated reservoir/river management. New hydrological insights for the region: After simulation of long-term meteorological series in a model of the integrated water system, covering several historical extreme events, results indicate that the planned irrigation volumes are higher than the available water for a sustainable irrigation strategy. Two lines of action are suggested for reaching the target irrigation demands: design of a deficit irrigation system, and modifications to the reservoir's spillway height. Keywords: Reservoir operation, Conceptual model, Irrigation

  16. A Reevaluation of Price Elasticities for Irrigation Water

    Science.gov (United States)

    Howitt, Richard E.; Watson, William D.; Adams, Richard M.

    1980-08-01

    The effectiveness of pricing systems in the allocation of irrigation water is linked with the price elasticity of demand of farmers for water. Using microeconomic theory, it is shown that omission of the elasticity of demand for the crop produced leads to an inelastic bias in the demand for irrigated water. Linear programing approaches omit the product elasticity of demand and are consequently biased, whereas quadratic programing approaches to estimating derived demands for irrigation water include product demand functions. The difference between the resulting estimates are empirically demonstrated for regional derived demand functions estimated from a model of California's agricultural industry.

  17. Simulated evapotranspiration from a landfill irrigated with landfill leachate

    International Nuclear Information System (INIS)

    Aronsson, P.

    1996-01-01

    Evapotranspiration from a landfill area, irrigated with leachate water, was simulated with the SOIL model. Three different types of vegetation (bare soil, grass ley, and willow) were used both with and without irrigation. The highest simulated evapotranspiration (604 mm) during the growing season was found from an irrigated willow stand with a high interception capacity. The lowest evapotranspiration (164 mm) was found from the bare soil. The relatively high evapotranspiration from the willow was probably caused by the high LAI (Leaf Area Index) and the low aerodynamic resistance within the willow stand. The results indicate that it is possible to reduce most of the leakage water from a landfill by irrigation of willow stands. 9 refs, 4 figs, 1 tab

  18. The success of a policy model: Irrigation management transfer in Mexico

    NARCIS (Netherlands)

    Rap, E.R.

    2004-01-01

    This thesis studies the emergence, process and outcomes of the Mexican policy of Irrigation Management Transfer (IMT). Under the influence of neo-liberal government policies, the transfer of government-managed irrigation districts to water users' associations (WUAs) has radically changed irrigation

  19. Crop yield response to deficit irrigation imposed at different plant growth stages

    International Nuclear Information System (INIS)

    Kovaks, T.; Kovaks, G.; Szito, J.

    1995-01-01

    A series of field experiments were conducted between 1991 - 1994 using 7 irrigation treatments at two fertilizer levels. Nitrogen fertilizers used were labelled with 15 N stable isotope to examine the effect of irrigation on the fertilizer N use efficiency by isotope technique. The irrigation were maintained at four different growth stages of maize, soybean and potato( vegetative, flowering, yield formation and ripening ) in 4 replicates. The aim of study was to compare deficit irrigation( i.e. the water stress imposed, during one growth stage ) with normal irrigation practice included the traditional one. Two watering regimes were established : (1) normal watering when available water was within the range of 60 - 90 %, and (2) deficit irrigation, when the AW was at 30 to 60 %. Neutron probe was used for measuring the soil water status and evaporation data were recorded to determine the amount of irrigation water demand. Reference evapotranspiration ( ETo) was calculated according to Penman - Monteith. Crop water requirement ( ETm) were determined in every year. Actual evapotranspiration ( ETa) was computed using CROPWAT: FAO computer program for irrigation planning and management (1992). Every irrigation treatment was equipped with neutron access tubes in two replicates at a depth from 10 to 130 cm. tensiometers were installed at depths of 30, 50, 60 and 80 cm in one replicate of treatments and were measured on a daily basis while neutron probe measurements were used to monitor the soil water table fluctuations. The irrigation method used was a special type of low pressure drop irrigation. There were measured the amount of rainfall with irrigation water supplied and the moisture distribution profiles were drown for the different treatments. Relationships between relative yield decrease and evapotranspiration and also between the crop yield and water use were determined. 9 tabs, 9 refs, ( Author )

  20. Behavioural modelling of irrigation decision making under water scarcity

    Science.gov (United States)

    Foster, T.; Brozovic, N.; Butler, A. P.

    2013-12-01

    Providing effective policy solutions to aquifer depletion caused by abstraction for irrigation is a key challenge for socio-hydrology. However, most crop production functions used in hydrological models do not capture the intraseasonal nature of irrigation planning, or the importance of well yield in land and water use decisions. Here we develop a method for determining stochastic intraseasonal water use that is based on observed farmer behaviour but is also theoretically consistent with dynamically optimal decision making. We use the model to (i) analyse the joint land and water use decision by farmers; (ii) to assess changes in behaviour and production risk in response to water scarcity; and (iii) to understand the limits of applicability of current methods in policy design. We develop a biophysical model of water-limited crop yield building on the AquaCrop model. The model is calibrated and applied to case studies of irrigated corn production in Nebraska and Texas. We run the model iteratively, using long-term climate records, to define two formulations of the crop-water production function: (i) the aggregate relationship between total seasonal irrigation and yield (typical of current approaches); and (ii) the stochastic response of yield and total seasonal irrigation to the choice of an intraseasonal soil moisture target and irrigated area. Irrigated area (the extensive margin decision) and per-area irrigation intensity (the intensive margin decision) are then calculated for different seasonal water restrictions (corresponding to regulatory policies) and well yield constraints on intraseasonal abstraction rates (corresponding to aquifer system limits). Profit- and utility-maximising decisions are determined assuming risk neutrality and varying degrees of risk aversion, respectively. Our results demonstrate that the formulation of the production function has a significant impact on the response to water scarcity. For low well yields, which are the major concern

  1. Web Publishing Schedule

    Science.gov (United States)

    Section 207(f)(2) of the E-Gov Act requires federal agencies to develop an inventory and establish a schedule of information to be published on their Web sites, make those schedules available for public comment. To post the schedules on the web site.

  2. Maximizing the value of limited irrigation water: USDA researchers study how producers on limited irrigation can save water and be profitable

    Science.gov (United States)

    Water shortages are responsible for the greatest crop losses around the world and are expected to worsen. In arid areas where agriculture is dependent on irrigation, various forms of deficit irrigation management have been suggested to optimize crop yields for available soil water. The relationshi...

  3. Status and migration of irrigation in the USA

    Science.gov (United States)

    Irrigated agriculture produces 49% of crop market value on 18% of cropped lands in the USA. Irrigation is essential to the most highly productive, intensely managed, and internationally competitive sectors of our agricultural economy, which play a key role in meeting growing global food, fiber, and ...

  4. Alfalfa response to irrigation from limited water supplies

    Science.gov (United States)

    A five-year field study (2007-2011) of irrigated alfalfa production with a limited water supply was conducted in southwest Kansas with two years of above-average precipitation, one year of average precipitation, and two years of below-average precipitation. The irrigation treatments were designed to...

  5. [Runoff Pollution Experiments of Paddy Fields Under Different Irrigation Patterns].

    Science.gov (United States)

    Zhou, Jing-wen; Su, Bao-lin; Huang, Ning-bo; Guan, Yu-tang; Zhao, Kun

    2016-03-15

    To study runoff and non-point source pollution of paddy fields and to provide a scientific basis for agricultural water management of paddy fields, paddy plots in the Jintan City and the Liyang City were chosen for experiments on non-point source pollution, and flood irrigation and intermittent irrigation patterns were adopted in this research. The surface water level and rainfall were observed during the growing season of paddies, and the runoff amount from paddy plots and loads of total nitrogen (TN) and total phosphorus (TP) were calculated by different methods. The results showed that only five rain events of totally 27 rainfalls and one artificially drainage formed non-point source pollution from flood irrigated paddy plot, which resulted in a TN export coefficient of 49.4 kg · hm⁻² and a TP export coefficient of 1.0 kg · hm⁻². No any runoff event occurred from the paddy plot with intermittent irrigation even in the case of maximum rainfall of 95.1 mm. Runoff from paddy fields was affected by water demands of paddies and irrigation or drainage management, which was directly correlated to surface water level, rainfall amount and the lowest ridge height of outlets. Compared with the flood irrigation, intermittent irrigation could significantly reduce non-point source pollution caused by rainfall or artificial drainage.

  6. Determinants of farmers' participation in collective maintenance of irrigation infrastructure in KwaZulu-Natal

    Science.gov (United States)

    Sharaunga, S.; Mudhara, M.

    2018-06-01

    The decentralization framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasize the need for a participatory approach to irrigation water management. This study identifies the factors influencing farmers' decision to, and extent of participation in the maintenance of irrigation infrastructure in KwaZulu-Natal province, South Africa based on cross-section data collected from 320 randomly selected smallholder irrigating farmers. A two-step Heckman regression model was applied in the analysis. It was established that households whose heads were older, block committee members, with larger irrigation plots, good soil quality and experiencing severe irrigation water shortages are more likely to participate in maintenance of irrigation infrastructure. On the other hand, farmers with insecure land tenure and with no access to irrigation water were less likely to make the decision to participate. Farmers who were members of the farming cooperative as well as block committee members and those paying irrigation water costs were likely to intensively participate in maintaining irrigation infrastructure. Therefore, decentralization alone cannot lead to improved irrigation outcomes. Several factors are necessary for households to participate intensively in the maintenance of irrigation infrastructure. Governments should address these challenges before handing irrigation schemes to their beneficiaries.

  7. Influencing Factors and Simplified Model of Film Hole Irrigation

    Directory of Open Access Journals (Sweden)

    Yi-Bo Li

    2017-07-01

    Full Text Available Film hole irrigation is an advanced low-cost and high-efficiency irrigation method, which can improve water conservation and water use efficiency. Given its various advantages and potential applications, we conducted a laboratory study to investigate the effects of soil texture, bulk density, initial soil moisture, irrigation depth, opening ratio (ρ, film hole diameter (D, and spacing on cumulative infiltration using SWMS-2D. We then proposed a simplified model based on the Kostiakov model for infiltration estimation. Error analyses indicated SWMS-2D to be suitable for infiltration simulation of film hole irrigation. Additional SWMS-2D-based investigations indicated that, for a certain soil, initial soil moisture and irrigation depth had the weakest effects on cumulative infiltration, whereas ρ and D had the strongest effects on cumulative infiltration. A simplified model with ρ and D was further established, and its use was then expanded to different soils. Verification based on seven soil types indicated that the established simplified double-factor model effectively estimates cumulative infiltration for film hole irrigation, with a small mean average error of 0.141–2.299 mm, a root mean square error of 0.177–2.722 mm, a percent bias of −2.131–1.479%, and a large Nash–Sutcliffe coefficient that is close to 1.0.

  8. Coastal surface water suitability analysis for irrigation in Bangladesh

    Science.gov (United States)

    Mahtab, Mohammad Hossain; Zahid, Anwar

    2018-03-01

    Water with adequate quality and quantity is very important for irrigation to ensure the crop yields. Salinity is common problem in the coastal waters in Bangladesh. The intensity of salinity in the coastal zone in Bangladesh is not same. It fluctuates over the year. Sodium is another hazard which may hamper permeability and ultimately affects the fertility. It can reduce the crop yields. Although surface water is available in the coastal zone of Bangladesh, but its quality for irrigation needs to be monitored over the year. This paper will investigate the overall quality of coastal surface waters. Thirty-three water samples from different rivers were collected both in wet period (October-December) and in dry period (February-April). Different physical and chemical parameters are considered for investigation of the adequacy of water with respect to international irrigation water quality standards and Bangladesh standards. A comparison between the dry and wet period coastal surface water quality in Bangladesh will also be drawn here. The analysis shows that coastal surface water in Bangladesh is overall suitable for irrigation during wet period, while it needs treatment (which will increase the irrigation cost) for using for irrigation during dry period. Adaptation to this situation can improve the scenario. An integrated plan should be taken to increase the water storing capacity in the coastal area to harvest water during wet period.

  9. Irrigation as an Adaptation Strategy to Climate Change: The Relative Influence of Groundwater and Canal Irrigation on Winter Crop Production and its Sensitivity to Weather Variability in India

    Science.gov (United States)

    Jain, M.; Fishman, R.; Mondal, P.; Galford, G. L.; Naeem, S.; Modi, V.; DeFries, R. S.

    2014-12-01

    India is a hotspot for food security issues over the upcoming decades, due to increasing population pressures, groundwater depletion, and climate change. Investing in additional irrigation infrastructure may bolster food security, however, the relative influence of different types of irrigation (e.g. groundwater versus canal) on agricultural production remains unclear. One reason that the relative impact of different irrigation strategies on agricultural production has not been analyzed across India is because national-scale data on crop production and the types of irrigation technologies used are typically available at too coarse of spatial and temporal resolutions to answer this question adequately. Thus, we develop a novel algorithm to map cropped area across India at a 1 x 1 km scale using MODIS satellite data, and link these high-resolution cropped area maps with village-level data (n = 600,000) on irrigation. This allowed us to assess the relative impact of groundwater (i.e. dug, shallow, and deep wells) and canal irrigation (i.e. surface lift and flow canals) on winter cropped area and its sensitivity to rainfall across India at the village-scale from 2000 to 2006. We find that deep well irrigation is both associated with the greatest amount of winter cropped area, and is also the least sensitive to monsoon and winter rainfall variability. However, the effectiveness of deep well irrigation varies across India, with the greatest benefits seen in the regions that are most at risk for losing groundwater as a possible source of irrigation over the upcoming decades (e.g. Northwest India). This work highlights the need to develop ways to use remaining groundwater more efficiently (e.g. drip irrigation, less water-intensive crops) given that canal irrigation is not an adequate substitute, particularly in the regions that are facing the greatest levels of groundwater depletion.

  10. AGROCLIMATIC DETERMINANTS OF IRRIGATION NEEDS

    Directory of Open Access Journals (Sweden)

    Leszek Łabędzki

    2016-05-01

    Full Text Available The paper is a review of the so far used in Poland methods and criteria for assessing the needs of irrigation for planning purposes, the assessment because of the agroclimatic conditions and taking into account the soil water retention. Irrigation needs of the most are determined taking into account crop water deficits. This is the factor that is characterized by a shortage of precipitation in relation to the water requirements of crops. Some methods use only the meteorological parameters that determine the state of the atmosphere-soil-plant system, and some also take into account soil water retention and its availability for plants.

  11. The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

    Science.gov (United States)

    Gao, Xuan

    2017-04-01

    Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally

  12. Mapping irrigated areas in Afghanistan over the past decade using MODIS NDVI

    Science.gov (United States)

    Pervez, Md Shahriar; Budde, Michael; Rowland, James

    2014-01-01

    Agricultural production capacity contributes to food security in Afghanistan and is largely dependent on irrigated farming, mostly utilizing surface water fed by snowmelt. Because of the high contribution of irrigated crops (> 80%) to total agricultural production, knowing the spatial distribution and year-to-year variability in irrigated areas is imperative to monitoring food security for the country. We used 16-day composites of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to create 23-point time series for each year from 2000 through 2013. Seasonal peak values and time series were used in a threshold-dependent decision tree algorithm to map irrigated areas in Afghanistan for the last 14 years. In the absence of ground reference irrigated area information, we evaluated these maps with the irrigated areas classified from multiple snapshots of the landscape during the growing season from Landsat 5 optical and thermal sensor images. We were able to identify irrigated areas using Landsat imagery by selecting as irrigated those areas with Landsat-derived NDVI greater than 0.30–0.45, depending on the date of the Landsat image and surface temperature less than or equal to 310 Kelvin (36.9 ° C). Due to the availability of Landsat images, we were able to compare with the MODIS-derived maps for four years: 2000, 2009, 2010, and 2011. The irrigated areas derived from Landsat agreed well r2 = 0.91 with the irrigated areas derived from MODIS, providing confidence in the MODIS NDVI threshold approach. The maps portrayed a highly dynamic irrigated agriculture practice in Afghanistan, where the amount of irrigated area was largely determined by the availability of surface water, especially snowmelt, and varied by as much as 30% between water surplus and water deficit years. During the past 14 years, 2001, 2004, and 2008 showed the lowest levels of irrigated area (~ 1.5 million hectares), attesting to

  13. Biomass Accumulation, Photosynthetic Traits and Root Development of Cotton as Affected by Irrigation and Nitrogen-Fertilization

    Directory of Open Access Journals (Sweden)

    Zongkui Chen

    2018-02-01

    Full Text Available Limitations of soil water and nitrogen (N are factors which cause a substantial reduction in cotton (Gossypium hirsutum L. yield, especially in an arid environment. Suitable management decisions like irrigation method and nitrogen fertilization are the key yield improvement technologies in cotton production systems. Therefore, we hypothesized that optimal water-N supply can increase cotton plant biomass accumulation by maintaining leaf photosynthetic capacity and improving root growth. An outdoor polyvinyl chloride (PVC tube study was conducted to investigate the effects of two water-N application depths, i.e., 20 cm (H20 or 40 cm (H40 from soil surface and four water-N combinations [deficit irrigation (W55 and no N (N0 (W55N0, W55 and moderate N (N1 (W55N1, moderate irrigation (W75 and N0 (W75N0, W75N1] on the roots growth, leaf photosynthetic traits and dry mass accumulation of cotton crops. H20W55N1 combination increased total dry mass production by 29–82% and reproductive organs biomass by 47–101% compared with other counterparts. Root protective enzyme and nitrate reductase (NR activity, potential quantum yield of photosystem (PS II (Fv/Fm, PSII quantum yield in the light [Y(II] and electron transport rate of PSII were significantly higher in H20W55N1 prior to 82 days after emergence. Root NR activity and protective enzyme were significantly correlated with chlorophyll, Fv/Fm, Y(II and stomatal conductance. Hence, shallow irrigation (20 cm with moderate irrigation and N-fertilization application could increase cotton root NR activity and protective enzyme leading to enhance light capture and photochemical energy conversion of PSII before the full flowering stage. This enhanced photoassimilate to reproductive organs.

  14. Production of mungbean under reclaimed sandy soil and irrigation levels using N-15 labeled

    International Nuclear Information System (INIS)

    Abdallah, A.A.G.; Thabet, E.M.A.

    2000-01-01

    Field experiment were performed at the Atomic Energy Authority, Experimental farm, Inshas, Egypt. During 1998 growing season. In tafla and sand mixture soil (1:7 Wt./Wt.). The treatments were laid out using a single line source sprinkler irrigation system which allows a gradual variation of irrigation from excess to little irrigation in which the calculated amount of irrigation water levels were 2241, 1562 and 1093 m 3 / feddan (W 1 , W 2 and W 3 ). The obtained results indicated that, there was a clear relationship between adequate amount of irrigation water and both total seed yield and total green pods/plot as well as there were significant increase in both characters due to irrigation W 1 and W 2 compared with W 3 . The results also indicated that W 2 irrigation level could be used in irrigation under the same conditions. Water use efficiency was significantly increased with middle irrigation level than with other two irrigation treatments. The result concerned fertilizer use efficiency using N 15 labeled fertilizers and total seed protein content were increased with decreasing irrigation level

  15. System contemplations for precision irrigation in agriculture

    Science.gov (United States)

    Schubert, Martin J. W.

    2017-04-01

    This communication contemplates political, biological and technical aspects for efficient and profitable irrigation in sustainable agriculture. A standard for irrigation components is proposed. The need for many, and three-dimensionally distributed, soil measurement points is explained, thus enabling the control of humidity in selected layers of earth. Combined wireless and wired data transmission is proposed. Energy harvesting and storage together with mechanical sensor construction are discussed.

  16. Temperature-controlled irrigated tip radiofrequency catheter ablation

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, Adrian

    1998-01-01

    INTRODUCTION: In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures radiofrequency ablation. Irrigated tip radiofrequency ablation using power control and high infusion rates enlarges lesion......: We conclude that temperature-controlled radiofrequency ablation with irrigated tip catheters using low target temperature and low infusion rate enlarges lesion size without increasing the incidence of cratering and reduces coagulum formation of the tip....

  17. Schedule Matters: Understanding the Relationship between Schedule Delays and Costs on Overruns

    Science.gov (United States)

    Majerowicz, Walt; Shinn, Stephen A.

    2016-01-01

    This paper examines the relationship between schedule delays and cost overruns on complex projects. It is generally accepted by many project practitioners that cost overruns are directly related to schedule delays. But what does "directly related to" actually mean? Some reasons or root causes for schedule delays and associated cost overruns are obvious, if only in hindsight. For example, unrealistic estimates, supply chain difficulties, insufficient schedule margin, technical problems, scope changes, or the occurrence of risk events can negatively impact schedule performance. Other factors driving schedule delays and cost overruns may be less obvious and more difficult to quantify. Examples of these less obvious factors include project complexity, flawed estimating assumptions, over-optimism, political factors, "black swan" events, or even poor leadership and communication. Indeed, is it even possible the schedule itself could be a source of delay and subsequent cost overrun? Through literature review, surveys of project practitioners, and the authors' own experience on NASA programs and projects, the authors will categorize and examine the various factors affecting the relationship between project schedule delays and cost growth. The authors will also propose some ideas for organizations to consider to help create an awareness of the factors which could cause or influence schedule delays and associated cost growth on complex projects.

  18. The maximum economic depth of groundwater abstraction for irrigation

    Science.gov (United States)

    Bierkens, M. F.; Van Beek, L. P.; de Graaf, I. E. M.; Gleeson, T. P.

    2017-12-01

    Over recent decades, groundwater has become increasingly important for agriculture. Irrigation accounts for 40% of the global food production and its importance is expected to grow further in the near future. Already, about 70% of the globally abstracted water is used for irrigation, and nearly half of that is pumped groundwater. In many irrigated areas where groundwater is the primary source of irrigation water, groundwater abstraction is larger than recharge and we see massive groundwater head decline in these areas. An important question then is: to what maximum depth can groundwater be pumped for it to be still economically recoverable? The objective of this study is therefore to create a global map of the maximum depth of economically recoverable groundwater when used for irrigation. The maximum economic depth is the maximum depth at which revenues are still larger than pumping costs or the maximum depth at which initial investments become too large compared to yearly revenues. To this end we set up a simple economic model where costs of well drilling and the energy costs of pumping, which are a function of well depth and static head depth respectively, are compared with the revenues obtained for the irrigated crops. Parameters for the cost sub-model are obtained from several US-based studies and applied to other countries based on GDP/capita as an index of labour costs. The revenue sub-model is based on gross irrigation water demand calculated with a global hydrological and water resources model, areal coverage of crop types from MIRCA2000 and FAO-based statistics on crop yield and market price. We applied our method to irrigated areas in the world overlying productive aquifers. Estimated maximum economic depths range between 50 and 500 m. Most important factors explaining the maximum economic depth are the dominant crop type in the area and whether or not initial investments in well infrastructure are limiting. In subsequent research, our estimates of

  19. Irrigated Area Maps and Statistics of India Using Remote Sensing and National Statistics

    Directory of Open Access Journals (Sweden)

    Prasad S. Thenkabail

    2009-04-01

    Full Text Available The goal of this research was to compare the remote-sensing derived irrigated areas with census-derived statistics reported in the national system. India, which has nearly 30% of global annualized irrigated areas (AIAs, and is the leading irrigated area country in the World, along with China, was chosen for the study. Irrigated areas were derived for nominal year 2000 using time-series remote sensing at two spatial resolutions: (a 10-km Advanced Very High Resolution Radiometer (AVHRR and (b 500-m Moderate Resolution Imaging Spectroradiometer (MODIS. These areas were compared with the Indian National Statistical Data on irrigated areas reported by the: (a Directorate of Economics and Statistics (DES of the Ministry of Agriculture (MOA, and (b Ministry of Water Resources (MoWR. A state-by-state comparison of remote sensing derived irrigated areas when compared with MoWR derived irrigation potential utilized (IPU, an equivalent of AIA, provided a high degree of correlation with R2 values of: (a 0.79 with 10-km, and (b 0.85 with MODIS 500-m. However, the remote sensing derived irrigated area estimates for India were consistently higher than the irrigated areas reported by the national statistics. The remote sensing derived total area available for irrigation (TAAI, which does not consider intensity of irrigation, was 101 million hectares (Mha using 10-km and 113 Mha using 500-m. The AIAs, which considers intensity of irrigation, was 132 Mha using 10-km and 146 Mha using 500-m. In contrast the IPU, an equivalent of AIAs, as reported by MoWR was 83 Mha. There are “large variations” in irrigated area statistics reported, even between two ministries (e.g., Directorate of Statistics of Ministry of Agriculture and Ministry of Water Resources of the same national system. The causes include: (a reluctance on part of the states to furnish irrigated area data in view of their vested interests in sharing of water, and (b reporting of large volumes of data

  20. The fluid mechanics of root canal irrigation.

    Science.gov (United States)

    Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

    2010-12-01

    Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

  1. The fluid mechanics of root canal irrigation

    International Nuclear Information System (INIS)

    Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

    2010-01-01

    Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

  2. Consumption and cost of diesel oil on cultivation of Zoysiagrass (Zoysia japonica Steud.) irrigated by aspersion canyons under two irrigation handlings

    Energy Technology Data Exchange (ETDEWEB)

    Mazaroni, Bruno Henrique Silveira; Turco, Jose Eduardo Pitelli; Coan, Ruchele Marchiori; Gerolineto, Eduardo [Universidade Estadual Paulista (FCAV/UNESP), Jaboticabal, SP (Brazil). Fac. de Ciencias Agrarias e Veterinarias

    2008-07-01

    This work aim to analyse the consumption and cost of diesel oil on cultivation of zoysiagrass (Zoysia japonica Steud.) irrigated by aspersion canyon, submitted of to two irrigation handling: T1 - irrigated when the tensiometer reading is equal - 0,5 atmospheres and T2 - irrigated by grass growers methodology. The research was carried on Green-Park Farm, in the city of Pitangueiras, SP. Consumption of diesel oil was measured from a diesel engine, brand MWM, turbined with 6 cylinders, type D-229 for zoysiagrass production. The diesel price was gotten from Petroleum National Agency (ANP), being an average price in Sao Paulo State, in February 2007, converted into the commercial dollar. Economical result was studied, subtracting the selling value of the grass, by the cost of the fuel consumed, for both T1 and T2 treatments. The treatment made by tensiometer showed greater diesel consumption, related to treatment T2, where the handling was made by the grass grower. (author)

  3. Irrigation in the Lower Durance: positive impacts of the agriculture

    International Nuclear Information System (INIS)

    Lacroix, M.; Blavoux, B.

    1995-01-01

    The water of river Durance is used to produce hydroelectricity and as stretch of water for tourism and since the thirteenth century for irrigation. The inherited situation is a well extended network of gravitation irrigation canals. This system is spendthrift of water, the water supplies are roughly 5 times the farming needs. The impact of this irrigation on the alluvial aquifer of the Lower Durance is the generalisation of the highest level of the water table in summer on the plain though the water budget has an average deficit of 550 mm. In addition, the nitrate concentration is maintained to an average of 17 mg/l in groundwater and 5 mg/l in streams by dilution. In fact, the irrigation dictates an average input of water with 25.4 mg/l of NO 3- . The natural isotopic tracing (oxygen 18) allows to say that 50 to 75% of the water of the alluvial aquifer come from irrigation. To improve the knowledge about the efficiency of irrigation, a mathematical groundwater model has been created. As a result, 53% of the water is lost while reaching the agricultural parcels, 19% is infiltrated during watering at the parcel and only 28% are used to satisfy the needs of plants. The realisation of this model has allowed to simulate the impact on groundwater of changes in irrigation practices which would lead to reduce the consummation of water. In the case of Lower Durance, the reduction of irrigation losses would have a strong impact on the quantity and quality of water in the alluvial aquifer. (J.S.). 10 refs., 9 figs., 2 tabs

  4. Heavy-metal contamination of agricultural soils irrigated with industrial effluents

    International Nuclear Information System (INIS)

    Nabi, G.; Ashraf, M.; Aslam, M. R.

    2001-01-01

    Pakistan is facing a thread of degradation of water and land-resources by industrial effluents. To evaluated the suitability of these effluents as a source of irrigation for agriculture and the study their effects on soil chemical properties, experiments were conducted in the industrial area of Sheikhupura, where effluent from Paper and Board Mill (PBM), Leather Industry (LI) and Fertilizer Industry (FI) were being used for irrigation. At each site, two fields were selected, one irrigated with industrial effluents and the other with tube-well/canal water. The soil samples were collected and analyzed for pH, ECe, SAR and for heavy metals, such as Cu, Cd, Cr, Zn, Pb, Mn, Fe, Al and Ni. Soil receiving effluent from LI showed higher ECe and SAR values, as compared to the soils receiving other effluents. The concentration of Al was high in the soil irrigated with LI effluent. The Mn and Fe contents were higher in soils irrigated with PBM effluent. Effluent from LI is not fit for irrigation, since its recipient soil showed high concentration of Cr and also high sodicity values. Except Cr, the heavy metals were not of environmental concern. (author)

  5. Coil irrigation in sugar cane (Saccharum officinarum

    Directory of Open Access Journals (Sweden)

    Jesús Sánchez Gutiérrez

    2016-01-01

    Full Text Available This study was made at the Basic Seed Bank of the Local Sugar Cane Research Station for the Mideastern Cuba, based in Camaguey, on brown carbonate soil, between 2013 and 12014. Coil irrigation was applied to meet the water requirements for the crop, according to the edafoclimatic conditions and the different phenological phases it has. The Savo method was used to determine useful rain water. Adjustment and complementation of the irrigation program was based on indicators that characterize the exploitation scheme. The machine´s working parameters were determined to meet the water needs, and increase crop´s overall yields. The evaluations and results achieved have contributed to new proposals for management and operation of coil irrigation, and they are important to increase its efficiency.

  6. The Reticulation Irrigation Scheme at Sankana, Upper West Region ...

    African Journals Online (AJOL)

    farmers utilizing the irrigation project are food secure. ... The effects of ... Often, lack of maintenance, bad management and financial difficulties decrease the ...... and Mushunje A. (2010), 'Analysis of Irrigation Development Post Fast Track Land ...

  7. Impact of upstream industrial effluents on irrigation water quality ...

    African Journals Online (AJOL)

    Impact of upstream industrial effluents on irrigation water quality, soils and ... Knowledge of irrigation water quality is critical to predicting, managing and reducing salt ... Presence of heavy metals in concentration higher than the recommended ...

  8. Remote Sensing of Irrigated Agriculture: Opportunities and Challenges

    Directory of Open Access Journals (Sweden)

    Chelsea Cervantes

    2010-09-01

    Full Text Available Over the last several decades, remote sensing has emerged as an effective tool to monitor irrigated lands over a variety of climatic conditions and locations. The objective of this review, which summarizes the methods and the results of existing remote sensing studies, is to synthesize principle findings and assess the state of the art. We take a taxonomic approach to group studies based on location, scale, inputs, and methods, in an effort to categorize different approaches within a logical framework. We seek to evaluate the ability of remote sensing to provide synoptic and timely coverage of irrigated lands in several spectral regions. We also investigate the value of archived data that enable comparison of images through time. This overview of the studies to date indicates that remote sensing-based monitoring of irrigation is at an intermediate stage of development at local scales. For instance, there is overwhelming consensus on the efficacy of vegetation indices in identifying irrigated fields. Also, single date imagery, acquired at peak growing season, may suffice to identify irrigated lands, although to multi-date image data are necessary for improved classification and to distinguish different crop types. At local scales, the mapping of irrigated lands with remote sensing is also strongly affected by the timing of image acquisition and the number of images used. At the regional and global scales, on the other hand, remote sensing has not been fully operational, as methods that work in one place and time are not necessarily transferable to other locations and periods. Thus, at larger scales, more work is required to indentify the best spectral indices, best time periods, and best classification methods under different climatological and cultural environments. Existing studies at regional scales also establish the fact that both remote sensing and national statistical approaches require further refinement with a substantial investment of

  9. Soil properties evolution after irrigation with reclaimed water

    Science.gov (United States)

    Leal, M.; González-Naranjo, V.; de Miguel, A.; Martínez-Hernández, V.; Lillo, J.

    2012-04-01

    Many arid and semi-arid countries are forced to look for new and alternative water sources. The availability of suitable quality water for agriculture in these regions often is threatened. In this context of water scarcity, the reuse of treated wastewater for crop irrigation could represent a feasible solution. Through rigorous planning and management, irrigation with reclaimed water presents some advantages such as saving freshwater, reducing wastewater discharges into freshwater bodies and decreasing the amount of added fertilizers due to the extra supply of nutrients by reclaimed water. The current study, which involves wastewater reuse in agriculture, has been carried out in the Experimental Plant of Carrión de los Céspedes (Sevile, Spain). Here, two survey parcels equally designed have been cultivated with Jatropha curcas L, a bioenergetic plant and a non-interfering food security crop. The only difference between the two parcels lies on the irrigation water quality: one is irrigated with groundwater and another one with reclaimed water. The main aim of this study focuses on analysing the outstanding differences in soil properties derived from irrigation with two water qualities, due to their implications for plant growth. To control and monitor the soil variables, soil samples were collected before and after irrigation in the two parcels. pH, electrical conductivity, cation exchange capacity, exchangeable cations (Ca2+, Mg2+, Na+ and K+), kjeldahl nitrogen, organic matter content and nutrients (boron, phosphorus, nitrogen, potassium) were measured. Data were statistically analyzed using the R package. To evaluate the variance ANOVA test was used and to obtain the relations between water quality and soil parameters, Pearson correlation coefficient was computed. According to other authors, a decrease in the organic matter content and an increase of parameters such as pH, electrical conductivity and some exchangeable cations were expected. To date and after

  10. Quixotic coupling between irrigation system and maize-cowpea ...

    African Journals Online (AJOL)

    A study was conducted at the Research and Experimental Station, Faculty of Agriculture, Ain Shams University at Shalakan, Kalubia Governorate, Egypt, to evaluate the effect of two irrigation systems (trickle and modified furrow irrigation) and five maize (M)-cowpea (C) intercropping patterns (sole M-30, sole M-15, ridge ...

  11. Performance evaluation of sprinkler irrigation system at Mambilla ...

    African Journals Online (AJOL)

    Variation in discharge can also be adjusted via use of uniform laterals, risers, and nozzles. This study further recommends an incorporation of a soil and water laboratory for the company to aid in monitoring the soil and water quality of the irrigation area. Keywords: Tea, irrigation System, Performance Evaluation ...

  12. The Current State of Predicting Furrow Irrigation Erosion

    Science.gov (United States)

    There continues to be a need to predict furrow irrigation erosion to estimate on- and off-site impacts of irrigation management. The objective of this paper is to review the current state of furrow erosion prediction technology considering four models: SISL, WEPP, WinSRFR and APEX. SISL is an empiri...

  13. IRRIGATION PRACTICES IN LONG-TERM SURVIVORS OF COLORECTAL CANCER (CRC) WITH COLOSTOMIES

    Science.gov (United States)

    Grant, Marcia; McMullen, Carmit K.; Altschuler, Andrea; Hornbrook, Mark C.; Herrinton, Lisa J.; Wendel, Christopher S.; Baldwin, Carol M.; Krouse, Robert S.

    2014-01-01

    Creation of a colostomy in colorectal (CRC) cancer patients results in a loss of control over bowel evacuation. The only way to re-establish some control is through irrigation, a procedure that involves instilling fluid into the bowel to allow for gas and fecal output. This article reports on irrigation practices of participants in a large, multi-site, multi-investigator study of health-related quality of life (HR-QOL) in long term CRC survivors. Questions about irrigation practices were identified in open-ended questions within a large HR-QOL survey and in focus groups of men and women with high and low HR-QOL. Descriptive data on survivors were combined with content analysis of irrigation knowledge and practices. Patient education and use of irrigation in the United States has decreased over the years, with no clear identification of why this change in practice has occurred. Those respondents who used irrigation had their surgery longer ago, and spent more time in colostomy care than those that did not irrigate. Reasons for the decrease in colostomy irrigation are unreported and present priorities for needed research. PMID:23022935

  14. Comparative evaluation of debris removal from root canal wall by using EndoVac and conventional needle irrigation: An in vitro study

    Directory of Open Access Journals (Sweden)

    Vandana J Gade

    2013-01-01

    Full Text Available Context: Microbial control is of paramount importance in Clinical Endodontics. Therefore, cleaning and disinfection of root canals are essential to achieve endodontic success. Aims: The purpose of this study is to compare the efficacy of EndoVac irrigation system and conventional needle (30 gauges side venting needle irrigation for removal of debris from the root canal walls at coronal, middle and apical third by using the scanning electron microscopy (SEM. Settings and Design: An in vitro randomized control trial study. Materials and Methods: A total of 20 mandibular premolars with completely formed roots were selected and randomly divided into two groups - Group 1: Irrigation with the Conventional system and Group 2: EndoVac irrigation. After access opening and working length determination biomechanical preparation completed up to a rotary protaper F4 file. Groupwise irrigation with sodium hypochlorite and ethylenediaminetetraacetic acid was done with each canal in between instrumentation. Then, the teeth were sectioned in buccolingual direction and the halves were sputter-coated with gold palladium and coronal, middle and apical third were examined by SEM at x2000 magnification. Statistical Analysis: Mann-Whitney test for comparison between methods, Kruskal-Wallis test for comparison among thirds and Miller test for individual comparisons. Results: The apical, middle and cervical root canal thirds were evaluated and the results were analyzed statistically by the Mann-Whitney test for comparison between methods, Kruskal-Wallis test for comparison among thirds and Miller test for individual comparisons. Conclusions: EndoVac group resulted in significantly less debris at apical third compared with the conventional needle irrigation group. There was no statistical significant difference found in debris removal at coronal and middle third of root canal wall between the EndoVac group and conventional needle irrigation group.

  15. Evaluation of soil and water salinity for irrigation in North-eastern ...

    African Journals Online (AJOL)

    For sound land use and water management in irrigated area, knowledge of the chemical composition of soils, water, climate, drainage condition and irrigation methods before action are crucial for sustainability of irrigation projects. The study aimed to evaluate the physicochemical properties of soils and water for intended ...

  16. Effect of different drip irrigation regimes on yield and oil quality of sunflower

    Directory of Open Access Journals (Sweden)

    Semih Metin SEZEN

    2016-06-01

    Full Text Available This study examines the effects of different irrigation regimes on yield, yield components, oil yield and quality and water use of sunflower (Oleko variety irrigated with a drip system under field conditions in 2010 and 2011 growing seasons at the Alata Horticultural Research Institute, Tarsus Soil and Water Resources area in the Mediterranean region of Turkey. Irrigation regimes consisted of three irrigation intervals (A1:= 25 mm; A2:= 50 mm; A3: = 75 mm of cumulative pan evaporation and six irrigation levels (I1=0.50, I2=0.75, I3=1.00 and I4=1.25. In addition, I5=PRD75 and I6=PRD50 treatments were considered. They received 75 and 50% of the full irrigation (I3 treatment from alternative laterals, respectively. Also, rainfed treatment is a control plot in the experiment. Maximum and minimum yields were obtained from the A2I4 and rainfed treatments, respectively in all experimental years. As the irrigation level value decreased the total yields in each irrigation interval also decreased. Seasonal irrigation amounts in the treatments varied from 199 mm to 563 mm in the experimental years. Seasonal evapotranspiration values in the treatments varied from 243 mm to 611 mm in the experimental years. Both irrigation amounts and irrigation frequencies had significantly effects on oil content of sunflower. The saturated (palmitic and stearic acid and unsaturated (oleic and linoleic acid fatty acid contents were significantly affected by water stress. In conclusion, A2I4 irrigation regime is recommended for sunflower production in the Mediterranean region in order to attain higher yields with improved quality. In case of water shortage, A2I13 irrigation regime is recommended to increase sunflower yield and quality.

  17. Analysis to develop a program for energy conservation in irrigated agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Cone, B.W.; Brix, V.L.; Eakin, D.E.; Laughlin, B.M.

    1978-09-01

    It is estimated by the FEA that 0.26 quadrillion Btus of energy is annually required to irrigate crops in the USA. The development of a DOE program for energy conservation in irrigation is described. Information is included on: studies of how this energy consumption can be reduced and by how much; engineering and economic studies of irrigation equipment and methods; proposals for improving the efficiency of pumps and prime movers; projects selected for demonstrating irrigation energy conservation; and recommendations for further research. (LCL)

  18. A comprehensive guide for designing more efficient irrigation systems with respect to application control

    Science.gov (United States)

    Khaddam, Issam; Schuetze, Niels

    2017-04-01

    The worldwide water scarcity problems are expected to aggravate due to the increasing population and the need to produce more food. Irrigated agriculture is considered the highest consumer of fresh water resources with a rate exceeds 70% of global consumption. Consequently, an improvement in the efficiency of all irrigation methods, such as furrow or drip irrigation, becomes more necessary and urgent. Therefore, a more precise knowledge about soil water distribution in the root zone and the water balance components is required. For this purpose and as a part of the SAPHIR project (Saxonian Platform for high Performance Irrigation), a 2D simulation- based study was performed with virtual field conditions. The study investigates the most important design parameters of many irrigation systems, such as irrigation intensity and duration, and shows there influence on the water distribution efficiency. Furthermore, three main soil textures are used to test the impact of the soil hydraulic properties on irrigation effectiveness. A numerous number of irrigation scenarios of each irrigation system was simulated using HYDRUS 2D. Thereafter, the results were digitally calculated, compiled and made available online in the so called "Irrigation Atlases". The irrigation atlases provide graphical results of the soil moisture and pressure head distributions in the root zone. Moreover, they contain detailed information of the water balance for all simulated scenarios. The most studies evaluate the irrigation water demands on local, regional or global scales and for that an efficient water distribution is required. In this context, the irrigation atlases can serve as a valuable tool for the implementation of planned irrigation measures.

  19. Irrigation efficiency and water-policy implications for river basin resilience

    Science.gov (United States)

    Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

    2014-04-01

    Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface water and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly considers three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

  20. Irrigation efficiency and water-policy implications for river-basin resilience

    Science.gov (United States)

    Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

    2013-07-01

    Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface- and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river-basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly examines policy frameworks in three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

  1. Monitoring and Evaluation of Cultivated Land Irrigation Guarantee Capability with Remote Sensing

    Science.gov (United States)

    Zhang, C., Sr.; Huang, J.; Li, L.; Wang, H.; Zhu, D.

    2015-12-01

    Abstract: Cultivated Land Quality Grade monitoring and evaluation is an important way to improve the land production capability and ensure the country food safety. Irrigation guarantee capability is one of important aspects in the cultivated land quality monitoring and evaluation. In the current cultivated land quality monitoring processing based on field survey, the irrigation rate need much human resources investment in long investigation process. This study choses Beijing-Tianjin-Hebei as study region, taking the 1 km × 1 km grid size of cultivated land unit with a winter wheat-summer maize double cropping system as study object. A new irrigation capacity evaluation index based on the ratio of the annual irrigation requirement retrieved from MODIS data and the actual quantity of irrigation was proposed. With the years of monitoring results the irrigation guarantee capability of study area was evaluated comprehensively. The change trend of the irrigation guarantee capability index (IGCI) with the agricultural drought disaster area in rural statistical yearbook of Beijing-Tianjin-Hebei area was generally consistent. The average of IGCI value, the probability of irrigation-guaranteed year and the weighted average which controlled by the irrigation demand index were used and compared in this paper. The experiment results indicate that the classification result from the present method was close to that from irrigation probability in the gradation on agriculture land quality in 2012, with overlap of 73% similar units. The method of monitoring and evaluation of cultivated land IGCI proposed in this paper has a potential in cultivated land quality level monitoring and evaluation in China. Key words: remote sensing, evapotranspiration, MODIS cultivated land quality, irrigation guarantee capability Authors: Chao Zhang, Jianxi Huang, Li Li, Hongshuo Wang, Dehai Zhu China Agricultural University zhangchaobj@gmail.com

  2. Yield loss and economic thresholds of yellow nutsedge in irrigated rice as a function of the onset of flood irrigation

    Directory of Open Access Journals (Sweden)

    Nixon da Rosa Westendorff

    2014-03-01

    Full Text Available Yellow nutsedge (Cyperus esculentus is adapted to flooding and reduces yield in irrigated rice. Information on the competitive ability of this weed with the crop and the size of the economic damage caused is lacking. Mathematical models quantify the damage to crops and support control decision-making. This study aimed to determine yield losses and economic thresholds (ET of this weed in the culture according to weed population and time of onset of irrigation of the crop. The field study was conducted in the agricultural year of 2010/2011 in Pelotas/RS to evaluate the competitive ability of BRS Querência in competition with different population levels of yellow nutsedge and two periods of onset of flood irrigation (14 and 21 days after emergence. The hyperbolic model satisfactorily estimated yield losses caused by yellow nutsedge. Population of yellow nutsedge was the variable most fitted to the model. The delay of seven days for the beginning of rice irrigation causes decrease in competitive ability of BRS Querência, and based on the ET calculated to the price paid for rice, it is necessary between two and thirteen plants m-2 weed to justify the control in the first and second period of irrigation, respectively. Increases in yield, price paid for rice and control efficiency of the herbicide, besides reduction of costs of controlling promote reduction of ET of yellow nutsedge in rice crops, justifying the adoption of control measures even at smaller weed population.

  3. Decision support system for surface irrigation design

    OpenAIRE

    Gonçalves, José M.; Pereira, L.S.

    2009-01-01

    The SADREG decision support system was developed to help decision makers in the process of design and selection of farm surface irrigation systems to respond to requirements of modernization of surface irrigation—furrow, basin, and border irrigation. It includes a database, simulation models, user-friendly interfaces, and multicriteria analysis models. SADREG is comprised of two components: design and selection. The first component applies database information, and through several si...

  4. Modernisation strategy for National Irrigation Systems in the Philippines

    NARCIS (Netherlands)

    Delos Reyes, Mona Liza Fortunado

    2017-01-01

    The performance of publicly funded canal irrigation systems or more commonly called national irrigation systems (NIS) in the Philippines remained below expectations despite considerable system rehabilitation and improvement efforts. The continued suboptimal performances were attributed to

  5. Decentralising Zimbabwe’s water management: The case of Guyu-Chelesa irrigation scheme

    Science.gov (United States)

    Tambudzai, Rashirayi; Everisto, Mapedza; Gideon, Zhou

    Smallholder irrigation schemes are largely supply driven such that they exclude the beneficiaries on the management decisions and the choice of the irrigation schemes that would best suit their local needs. It is against this background that the decentralisation framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasise the need for a participatory approach to water management. The Zimbabwean government has gone a step further in decentralising the management of irrigation schemes, that is promoting farmer managed irrigation schemes so as to ensure effective management of scarce community based land and water resources. The study set to investigate the way in which the Guyu-Chelesa irrigation scheme is managed with specific emphasis on the role of the Irrigation Management Committee (IMC), the level of accountability and the powers devolved to the IMC. Merrey’s 2008 critique of IWRM also informs this study which views irrigation as going beyond infrastructure by looking at how institutions and decision making processes play out at various levels including at the irrigation scheme level. The study was positioned on the hypothesis that ‘decentralised or autonomous irrigation management enhances the sustainability and effectiveness of irrigation schemes’. To validate or falsify the stated hypothesis, data was gathered using desk research in the form of reviewing articles, documents from within the scheme and field research in the form of questionnaire surveys, key informant interviews and field observation. The Statistical Package for Social Sciences was used to analyse data quantitatively, whilst content analysis was utilised to analyse qualitative data whereby data was analysed thematically. Comparative analysis was carried out as Guyu-Chelesa irrigation scheme was compared with other smallholder irrigation scheme’s experiences within Zimbabwe and the Sub Saharan African region at large. The findings were that whilst the

  6. Colostomy irrigation: results of 25 cases with particular reference to quality of life.

    Science.gov (United States)

    Karadağ, Ayişe; Menteş, B Bülent; Ayaz, Sultan

    2005-04-01

    The aim of this study was to document our results with colostomy irrigation with particular emphasis on the possible contribution of irrigation on quality of life. Colostomy irrigation is a useful method of achieving faecal continence in selected conditions, and may improve quality of life. When successful, irrigation offers a regular, predictable elimination pattern and only a small covering is needed for security between irrigations. The digestive disease quality of life questionnaire-15 (DDQ-15) and Short Form-36 were used to analyse quality of life before and 12 months after stomatherapy in a series of 25 irrigating patients with permanent end colostomies. During the same time period, 10 similar patients with left-end colostomies who also received counselling but did not consent to colostomy irrigation were also analysed for comparison. Colostomy irrigation was found to be effective for achieving faecal continence in selected patients with end colostomies with no complications or significant side-effects, The digestive disease quality of life questionnaire-15 score improved significantly in both groups after stomatherapy (P colostomy irrigation can be a useful method of achieving faecal continence in selected conditions, it is safe, and it may help improve many aspects of quality of life. Colostomy irrigation is free from complications and significant side-effects, and it may serve as a useful adjunct to conventional stomatherapy. Therefore, the enterostomal therapy nurse should assess the appropriateness of routine irrigation as a method of stoma management for patients with left-end colostomy.

  7. New technologies for modernization and management of irrigation piping

    Directory of Open Access Journals (Sweden)

    Alessandro Santini

    2006-07-01

    Full Text Available Improving the efficiency of irrigation piping-systems represents a fundamental prerequisite to achieve a sustainable irrigation under both the environmental the economic point of view. Such an issue is important not only in areas with limited water-budget, but even in those areas where the increasing reduction of the water availability has become a worrying perspective. In the last twenty years, the reduction in water-availability and the increasing costs of system-management have highly limited the cultivated areas which are irrigated by means of water-distribution nets. In the recent years, most of the Italian investments in the irrigation-field have been oriented toward upgrading the open-channels irrigation nets, which were built starting from 50’, by substituting these latter with pipes. The modernization of the piping-systems has been achieved via innovative design solutions, such as back and loading water tanks or towers, which have lead to an improvement into the flexibility of the net management. Nearby the employment of such technologies, nowadays it is also possible to use the knowledge of the physical processes involved in the management of an irrigation system, starting from energy as well as mass exchange in the continuum soil-plant-atmosphere till to a detailed hydraulic description of a water distribution net under different flow regimes. Such a type of knowledge may be used to improve as well as buildup mathematical models for a decisions-support toward the management of complex irrigation districts. The acquirement of the data needed to implement such models has been deeply improved thanks to Geographical Information Systems (GIS, and techniques to analyze satellite-data coming from the Earth observation, which enable to characterize and monitor vegetation at different spatial, spectral and radiometric resolutions.

  8. 29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

    Science.gov (United States)

    2010-07-01

    ... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee... 29 Labor 3 2010-07-01 2010-07-01 false Scheduling of intermittent or reduced schedule leave. 825... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the...

  9. Identification of Water Usage Efficiency for Corn(Zea mays L.Lines Irrigated with Drip Irrigation Under Green House Conditions asPer Plant Water Stress Index Evaluations

    Directory of Open Access Journals (Sweden)

    Ali Beyhan UÇAK

    2017-02-01

    Full Text Available The present study was conducted as a greenhouse study under Çukurova conditions during the years2011-2012. Two different dent corn lines (5A2-B and 22K were used as the plant material of the experiments. Crop water stress index (CWSI values determined through leaf canopy temperature measurements performed ahead of irrigations were used to find outwater use efficiencies. Experiments were conducted in randomized blocks-split plots experimental design with three replications. Drip irrigation was used for irrigations and two different irrigation programs were created as of I100(supplying 100% of depleted water in every seven days and I75(applying 75% of depleted water. The amount of irrigation water applied for in the interaction of I100irrigation and corn lines (5A2-B and22K in the first and second year were respectively varied between 253.0-274.0and between 238.0-261.0mm, seasonal plant water consumptions varied between 294.0-305.0and between 284.6-302.6 mm, kernel yields varied between 2950.0-2990.0 and between 3130.0-3186.0kgha-1. With regard to (in the interaction irrigation treatments xcorn lines, the lowest and the highest CWSI values were observed in the interaction full irrigation (I100 and of the line 22K as 0.22 and in deficit irrigation treatment (I75 of the line 5A2-B as 0.41in the first year; in full irrigation treatment (I100 of the line 22K as 0.20 and in deficit irrigation treatment (I75 of the line 5A2-B as 0.36. The greatest and the lowest chlorophyll contents (in the interaction irrigation treatments x corn lines were respectively observed in I100treatment of the line 22K as 58.3 spad and in I75treatment of the line 5A2-Bas 50.9 spad in the first year; in I100treatment of the line 22K as 59.1 SPAD and in I75treatment of the line 5A2-B as 55.1 spad. While the effects of irrigation treatments on average dry matter contents of the lines were not found to be significant, significant differences were observed in water use efficiency

  10. ATLAS construction schedule

    CERN Multimedia

    Kotamaki, M

    The goal during the last few months has been to freeze and baseline as much as possible the schedules of various ATLAS systems and activities. The main motivations for the re-baselining of the schedules have been the new LHC schedule aiming at first collisions in early 2006 and the encountered delays in civil engineering as well as in the production of some of the detectors. The process was started by first preparing a new installation schedule that takes into account all the new external constraints and the new ATLAS staging scenario. The installation schedule version 3 was approved in the March EB and it provides the Ready For Installation (RFI) milestones for each system, i.e. the date when the system should be available for the start of the installation. TCn is now interacting with the systems aiming at a more realistic and resource loaded version 4 before the end of the year. Using the new RFI milestones as driving dates a new summary schedule has been prepared, or is under preparation, for each system....

  11. Can deficit irrigation techniques be used to enhance phosphorus and water use efficiency and benefit crop yields?

    Science.gov (United States)

    Wright, Hannah R.; Dodd, Ian C.; Blackwell, Martin S. A.; Surridge, Ben W. J.

    2015-04-01

    Soil drying and rewetting (DRW) affects the forms and availability of phosphorus (P). Water soluble P has been reported to increase 1.8- to 19-fold after air-drying with the majority of the increase (56-100%) attributable to organic P. Similarly, in two contrasting soil types DRW increased concentrations of total P and reactive P in leachate, likely due to enhanced P mineralisation and physiochemical processes causing detachment of soil colloids, with faster rewetting rates related to higher concentrations of P. The intensity of drying as well as the rate of rewetting influences organic and inorganic P cycling. How these dynamics are driven by soil water status, and impact crop P acquisition and growth, remains unclear. Improving P and water use efficiencies and crop yields is globally important as both P and water resources become increasingly scarce, whilst demand for food increases. Irrigation supply below the water requirement for full crop evapotranspiration is employed by agricultural practitioners where water supply is limited. Regulated deficit irrigation describes the scheduling of water supply to correspond to the times of highest crop demand. Alternate wetting and drying (AWD) is applied in lowland irrigated rice production to avoid flooding at certain times of crop development, and has benefited P nutrition and yields. This research aims to optimise the benefits of P availability and uptake achieved by DRW by guiding deficit irrigation management strategies. Further determination of underlying processes driving P cycling at fluctuating soil moisture status is required. Presented here is a summary of the literature on DRW effects on soil P availability and plant P uptake and partitioning, in a range of soil types and cropping systems, with emphasis on alternate wetting and drying irrigation (AWD) compared to continuous flooding in lowland irrigated rice production. Soil water contents and matric potentials, and effects on P dynamics, are highly variable

  12. Economic risk assessment of drought impacts on irrigated agriculture

    Science.gov (United States)

    Lopez-Nicolas, A.; Pulido-Velazquez, M.; Macian-Sorribes, H.

    2017-07-01

    In this paper we present an innovative framework for an economic risk analysis of drought impacts on irrigated agriculture. It consists on the integration of three components: stochastic time series modelling for prediction of inflows and future reservoir storages at the beginning of the irrigation season; statistical regression for the evaluation of water deliveries based on projected inflows and storages; and econometric modelling for economic assessment of the production value of agriculture based on irrigation water deliveries and crop prices. Therefore, the effect of the price volatility can be isolated from the losses due to water scarcity in the assessment of the drought impacts. Monte Carlo simulations are applied to generate probability functions of inflows, which are translated into probabilities of storages, deliveries, and finally, production value of agriculture. The framework also allows the assessment of the value of mitigation measures as reduction of economic losses during droughts. The approach was applied to the Jucar river basin, a complex system affected by multiannual severe droughts, with irrigated agriculture as the main consumptive demand. Probability distributions of deliveries and production value were obtained for each irrigation season. In the majority of the irrigation districts, drought causes a significant economic impact. The increase of crop prices can partially offset the losses from the reduction of production due to water scarcity in some districts. Emergency wells contribute to mitigating the droughts' impacts on the Jucar river system.

  13. Evaluation of dripper clogging using magnetic water in drip irrigation

    Science.gov (United States)

    Khoshravesh, Mojtaba; Mirzaei, Sayyed Mohammad Javad; Shirazi, Pooya; Valashedi, Reza Norooz

    2018-06-01

    This study was performed to investigate the uniformity of distribution of water and discharge variations in drip irrigation using magnetic water. Magnetic water was achieved by transition of water using a robust permanent magnet connected to a feed pipeline. Two main factors including magnetic and non-magnetic water and three sub-factor of