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Sample records for irrigation method electronic

  1. 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...

  2. 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.

  3. 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

  4. 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.

  5. 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...

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. A comparative study on drip and furrow irrigation methods

    International Nuclear Information System (INIS)

    Babar, M.M.; Shaikh, A.

    2008-01-01

    This study was conducted at Field Laboratory of the IIDE-MUET (Institute of lrrigation and Drainage Engineering, Mehran University of Engineering and Technology), Jamshoro in April 2007 and completed in October 2007. The soil was out-wash of the surrounding hilly tracts. Thus, the texture of the soil was sandy loam mixed with various sizes of gravels. Consequently, its water holding capacity was low and drainability high. The field capacity, wilting point and available moisture of the soil were found to be 10.35, 5.56 and 4.79%, respectively. The soil was moderate (ECe 8-16 dS/m) to strongly saline (ECe> 16 dS/m) and slightly sodic in nature in drip and furrow irrigated plots under study before start of vegetable crops. Three summer vegetables, i.e. okra, long gourd and ridge gourd were cultivated under drip and furrow systems of irrigation. Tap water was used for irrigation, which was class-I quality water i.e. nonsaline and non-sodic. Yields of the three respective vegetables were 25, 16.5 and 7.9% higher than the yields obtained from furrow method. Likewise, WUE (Water Use Efficiency) was higher in drip at 1.27, 3.19 and 2.28 Kg/m/sup 3/ against 0.59, 1.46 and 1.16 Kg/m/sup 3/ in furrow for the respective vegetables. The water saving in drip over furrow method for okra, long gourd and ridge gourd was estimated at 42.2, 46.9 and 45.0%, respectively. The soil salinity and sodicity decreased and did not develop within wetted zone under drip irrigation method and at furrow beds. However the same increased at the wetted periphery and at tops of the ridges under drip and furrow methods of irrigation respectively. (author)

  11. Improved methods for irrigation and planting of major crops in waterlogged areas

    International Nuclear Information System (INIS)

    Kahlown, M.A.; Iqbal, M.; Raoof, A.

    2002-01-01

    The improved irrigation methods for wheat and cotton were evaluated in the fordwah Eastern Sadigia (South) Irrigation and Drainage Project area, during 1996-97 and 1997-98 cropping seasons, under three water table depths. Irrigation methods for wheat included 70, 95 and 120 cm Beds, with Flat Basin, as a check for comparative evaluation. Cotton had Ridge-planting on the top and side, Bed and Furrow, and Flat Basin as control. These irrigation methods were compared at water table depths of < 1 m, 1-2 and 2-3 m. The wheat variety inqalab-91, and cotton cultivar, CIM-109, were planted during the 3rd week of November and May every year. All the inputs and management practices, such as seed-rate, fertilizer, seeding method, weed control, plant-protection measures, etc. were kept common. The results on cotton indicated maximum water-use efficiency with the Bed and Furrow Method of irrigation Followed by ridge planting. The traditional Flat-planting had the lowest yield and the highest water-consumption, resulting in the minimum water-use efficiency. In harmony with cotton, the Flat Method of planting had maximum water-consumption. For wheat crop, the water-use efficiency was in descending order, with 120, 95 and 70 cm for Bed and Flat Methods. Bed planting of 95 cm had a fairly high water-use efficiency and yields were more were more comparable than Flat planting. This method had a high level of adaptabilities, especially when the groundwater was close to the root-zone and higher possibilities, especially when the groundwater was close to the root-zone and higher possibility of crop-submergence are existent during rainy spells. The results of the investigation strongly favoured the Bed and furrow methods to irrigate cotton and wheat. However, under well-drained soil conditions, Bed planting of wheat is not recommended. (author)

  12. Impact of Irrigation Method on Water Use Efficiency and Productivity of Fodder Crops in Nepal

    Directory of Open Access Journals (Sweden)

    Ajay K Jha

    2016-01-01

    Full Text Available Improved irrigation use efficiency is an important tool for intensifying and diversifying agriculture in Nepal, resulting in higher economic yield from irrigated farmlands with a minimum input of water. Research was conducted to evaluate the effect of irrigation method (furrow vs. drip on the productivity of nutritious fodder species during off-monsoon dry periods in different elevation zones of central Nepal. A split-block factorial design was used. The factors considered were treatment location, fodder crop, and irrigation method. Commonly used local agronomical practices were followed in all respects except irrigation method. Results revealed that location effect was significant (p < 0.01 with highest fodder productivity seen for the middle elevation site, Syangja. Species effects were also significant, with teosinte (Euchlaena mexicana having higher yield than cowpea (Vigna unguiculata. Irrigation method impacted green biomass yield (higher with furrow irrigation but both methods yielded similar dry biomass, while water use was 73% less under drip irrigation. Our findings indicated that the controlled application of water through drip irrigation is able to produce acceptable yields of nutritionally dense fodder species during dry seasons, leading to more effective utilization and resource conservation of available land, fertilizer and water. Higher productivity of these nutritional fodders resulted in higher milk productivity for livestock smallholders. The ability to grow fodder crops year-round in lowland and hill regions of Nepal with limited water storages using low-cost, water-efficient drip irrigation may greatly increase livestock productivity and, hence, the economic security of smallholder farmers.

  13. Effects of different irrigation methods on pepper yield and soilborne diseases incidence

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    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.

  14. 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.

  15. Incidence of bacterial diseases associated with irrigation methods on onions (Allium cepa).

    Science.gov (United States)

    Chorolque, A; Pozzo Ardizzi, C; Pellejero, G; Aschkar, G; García Navarro, F J; Jiménez Ballesta, R

    2018-04-24

    In the last decade, diseases of bacterial origin in onions have increased and this has led to significant losses in production. These diseases are currently observed in both the Old and New Worlds. The aim of the experimental work reported here was to evaluate whether the irrigation method influences the incidence of diseases of bacterial origin. In cases where the inoculum was natural, the initial incidence of Soft Bacterial Rot was not manifested in any treatment in the first year, whereas at the end of the conservation period all treatments had increased incidences of infection. Sprinkler irrigation (8%) was statistically differentiated from the other treatments, for which the final incidence was similar (4.5%). For all irrigation treatments, the final incidence of Bacterial Soft Rot decreased or remained stable towards the end of the cycle, with the exception of sprinkler irrigation in 2015, which increased. It can be inferred from the results that the irrigation method does have an influence on the incidence of diseases of bacterial origin in the post-harvest stage for onions. This article is protected by copyright. All rights reserved.

  16. 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.

  17. 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

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

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    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.

  19. Effect of Different Irrigation and Planting Methods on Water Productivity and Health of Commercial Varieties of Potato

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    H. R Salemi

    2016-07-01

    Full Text Available Introduction Water crisis as a main factor of agronomy limitation exists in all over the arid and semiarid regions such as Isfahan, province which is located in the central part of the Zayandehrud River Basin (ZRB. Due to the increase in the cultivated area of potato in Fareidan Region located in the west of Isfahan province, it will be necessary to use pressurized irrigation systems to achieve the highest irrigation application efficiency and water productivity. Materials and Methods The ZRB (41,500 km2 is a closed basin with no outlet to the sea. The research was conducted in the Fareidan region of Isfahan, which is located in the west part of the ZRB. The Rozveh Agricultural Research Station (32°, 58' N, 50°, 25' E is located at the altitude of 2390 m above the sea level. This study was conducted as a randomized complete blocks design as a split strip plot layout with three replications and during two years (2007-2008. Three irrigation systems (Drip tape, Sprinkler and furrow were considered as main plots, two planting methods (one - row planting and two-row planting as split subplots and two potato cultivars (Marfuna and Agria as split-split subplots. Production (Tuber-yield, the consumption water and cultivars reactions to common diseases were evaluated in different treatments. The soil of the experimental area, according to USDA Soil Taxonomy 1994 is of silty loamy. At the soil depth of 1m, soil salinity (1.1-2.0 dS m-1, water salinity (1.24 dS m-1, soil moisture at field capacity (23 Vol. %, and bulk density (BD = 1.44 g/cm3 at the field site were measured or experimentally obtained in the Isfahan Soil and Water Laboratory. The results were subjected to an ANOVA to analyze the effects of the treatments and their interactions. The data obtained were analyzed using the compound variance analysis and the averages of different treatments were separated using the Duncan multiple range test using the statistical software (SAS Institute, Inc

  20. 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.

  1. 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.

  2. Design of a micro-irrigation system based on the control volume method

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    Chasseriaux G.

    2006-01-01

    Full Text Available A micro-irrigation system design based on control volume method using the back step procedure is presented in this study. The proposed numerical method is simple and consists of delimiting an elementary volume of the lateral equipped with an emitter, called « control volume » on which the conservation equations of the fl uid hydrodynamicʼs are applied. Control volume method is an iterative method to calculate velocity and pressure step by step throughout the micro-irrigation network based on an assumed pressure at the end of the line. A simple microcomputer program was used for the calculation and the convergence was very fast. When the average water requirement of plants was estimated, it is easy to choose the sum of the average emitter discharge as the total average fl ow rate of the network. The design consists of exploring an economical and effi cient network to deliver uniformly the input fl ow rate for all emitters. This program permitted the design of a large complex network of thousands of emitters very quickly. Three subroutine programs calculate velocity and pressure at a lateral pipe and submain pipe. The control volume method has already been tested for lateral design, the results from which were validated by other methods as fi nite element method, so it permits to determine the optimal design for such micro-irrigation network

  3. 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)

  4. Effect of Irrigation Methods, Nitrogen and Phosphorus Fertilizer Rates on Sugar Beet Yield and Quality

    International Nuclear Information System (INIS)

    Janat, M.; Abudlkareem, J.

    2007-01-01

    The experiment was conducted at a research station near Adlib. Two irrigation methods, sprinkler irrigation and drip fertigation, two phosphorus rates and four nitrogen rates 0, 70, 140 and 210 kg N/ha were tested. All N fertilizers were injected for drip irrigation or broadcasted for the sprinkler-irrigated treatments in six equally split applications. Neutron probe Results revealed that the introduction of drip fertigation was not proved to be a water saving relative to sprinkler irrigation. Dry matter production was slightly increased for the drip-fertigated treatments relative to sprinkler irrigated treatments. Nitrogen use efficiency was not improved under drip fertigation relative to that of sprinkler irrigation. Application of phosphorus fertilizer improved sugar beet yield as well as N uptake. No significant differences in sugar beet yield were observed due to the application of N fertilizer under drip fertigation. On the other hand, there was a trend toward increasing sugar beet yield grown under sprinkler irrigation. Drip fertigation had no negative effects on sugar content and other related properties, furthermore some of those properties were enhanced due to the employment of drip fertigation. Field water-use efficiency followed a similar trend and was increased under sprinkler irrigation relative to drip-fertigation for sugar beet yield parameter.

  5. 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.

  6. 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...

  7. Long-term Effects of Different Irrigation Methods with Treated Wastewater on Soil Chemical Properties

    Directory of Open Access Journals (Sweden)

    P. Najafi

    2016-02-01

    Full Text Available Introduction: Reuse of wastewater for agricultural irrigation is increasing due to an increased demand for water resources in different parts of the world. Almost 70% of deviated water from rivers and pumped groundwater is used for agriculture. If wastewater is used for irrigation in agriculture, then the amount of discharged water from natural sources will be decreased and the flow of wastewater to the environment and its ensuing pollution will be prevented. Using wastewater in applications such as irrigation of agricultural lands has caused an increase of some exchangeable ions, salts and suspended solids (organic and mineral in the soil and has significantly affected physical, chemical and biological features. Therefore, paying attention to the soil health is important during use of wastewater when it is the source of irrigation water. In such cases, there will be some worries about pollution of harvested products, contact of farm workers with pathogenes and environmental issues in the farm. In these conditions, attention to irrigation methods along with consideration of environmental protection standards is important. Materials and Methods: In this study, the effects of treated wastewater (TW irrigation were tested on some chemical properties of soil for three years under five different irrigation treatments. The treatments were as follows: surface furrow irrigation (FI, surface drip irrigation (SDI, subsurface drip irrigation in 30 cm depth (SDI30, subsurface drip irrigation in 60 cm depth (SDI60 and bubbler irrigation (BI. At the end of the experiment, soil samples were collected from a depth of 0-30, 30-60 and 60-90 cm in order to measure the electrical conductivity (EC, pH, sodium adsorption ratio (SAR, organic matter (OM and calcium carbonate equivalent (CaCO3. Results and Discussion: According to the results of soil analysis, the soil became more saline than the beginning by applying the treatments. Generally, in two plots of urban and

  8. 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

  9. 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)

  10. 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...

  11. 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.

  12. 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

  13. Response of Cotton to Irrigation Methods and Nitrogen Fertilization: Yield Components, Water-Use Efficiency, Nitrogen Uptake, and Recovery

    International Nuclear Information System (INIS)

    Janat, M.

    2009-01-01

    Efficient crop use of nitrogen (N) fertilizer is critical from economic and environmental viewpoints, especially under irrigated conditions. Cotton yield parameters, fiber quality, water- and N-use efficiency responses to N, and irrigation methods in northern Syria were evaluated. Field trials were conducted for two growing seasons on a Chromoxerertic Rhodoxeralf soil. Treatments consisted of drip fertigation, furrow irrigation, and five different rates of N fertilizer (50, 100, 150, 200, and 250 kg N /ha). Cotton was irrigated when soil moisture in the specified active root depth was 80% of the field capacity as indicated by the neutron probe. Seed cotton yield was higher than the national average (3,928 kg/ha) by at least 12% as compared to all treatments. Lint properties were not negatively affected by the irrigation method or N rates. Water savings under drip fertigation ranged between 25 and 50% of irrigation water relative to furrow irrigation. Crop water-use efficiencies of the drip-fertigated treatments were in most cases 100% higher than those of the corresponding furrow-irrigated treatments. The highest water demand was during the fruit-setting growth stage. It was also concluded that under drip fertigation, 100 -150 N kg/ha was adequate and comparable with the highest N rates tested under furrow irrigation regarding lint yield, N uptake, and recovery. Based on cotton seed yield and weight of stems, the overall amount of N removed from the field for the drip-fertigated treatments ranged between 101-118 kg and 116-188 N/ha for 2001 and 2002, respectively. The N removal ranged between 94-113 and 111-144 kg N/ha for the furrow-irrigated treatments for 2001 and 2002, respectively. (author)

  14. 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)

  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. 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.

  17. Influence of irrigation method and container type on Northern red oak seedling growth and media electrical conductivity

    Science.gov (United States)

    Anthony S. Davis; Douglass F. Jacobs; Ronald P. Overton; R. Kasten Dumroese

    2008-01-01

    Container production of hardwood seedlings has not been extensively practiced. Efficient nursery production of hardwood seedlings in containers can be limited by formation of a broad foliar canopy, which limits irrigation uniformity. This study was established to investigate suitability of subirrigation, a method of irrigating seedlings from the container base that...

  18. Effect of Different Methods of Chemical Weed Control Irrigation Regimes on Weed Biomass and Safflower Yield

    Directory of Open Access Journals (Sweden)

    M. Matinfar

    2011-06-01

    Full Text Available In order to investigate the effects of different weed control methods and moisture regimes on safflower (Carthamus tinctorius, a field split plot experiment based on randomized complete block design with 4 replications was conducted in Takestan Iran, during growing seasons of 2007-8. Three irrigations regimes (normal irrigation, restricted irrigation at stem elongation and restricted irrigation at  flowering stage were assigned to the main plots and nine chemical weed control method (complete hand weeding, treflan with 2 L/ha as pre plant herbicide, sonalan with 3 L/ha ad pre plant herbicide, estomp with 3 L/ha as pre plant herbicide, gallant super with 0/75 L/ha as post emergence herbicide, treflan with 2 L/ha as pre plant herbicide+ gallant super with 0/75 L/ha as post emergence herbicide, sonalan with 3 L/ha as pre plant herbicide + gallant super with 0/75 L/ha as post emergence herbicide estomp with 3 L/ha as pre plant herbicide + gallant super with 0/75 L/ha as post emergence herbicide and without hand weeding to sub- plots. At the end of growing period traits like number of head   per plant, number of seed per head, 1000 grain weight, percent of seed oil, yield of seed oil and grain yield were measured. Results indicated that treflan + gallant super treatment in restricted irrigation at stem elongation stage had the lowest dry weight of weeds. In this study maximum grain yield (2927 Kg/ha was achieved from hand weeding + usual irrigation treatments. In general treflan + gallant super treatment was the most effective treatment on safflower yield and weed control.

  19. 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.

  20. 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

  1. 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.

  2. Geospatial distribution modeling and determining suitability of groundwater quality for irrigation purpose using geospatial methods and water quality index (WQI) in Northern Ethiopia

    Science.gov (United States)

    Gidey, Amanuel

    2018-06-01

    Determining suitability and vulnerability of groundwater quality for irrigation use is a key alarm and first aid for careful management of groundwater resources to diminish the impacts on irrigation. This study was conducted to determine the overall suitability of groundwater quality for irrigation use and to generate their spatial distribution maps in Elala catchment, Northern Ethiopia. Thirty-nine groundwater samples were collected to analyze and map the water quality variables. Atomic absorption spectrophotometer, ultraviolet spectrophotometer, titration and calculation methods were used for laboratory groundwater quality analysis. Arc GIS, geospatial analysis tools, semivariogram model types and interpolation methods were used to generate geospatial distribution maps. Twelve and eight water quality variables were used to produce weighted overlay and irrigation water quality index models, respectively. Root-mean-square error, mean square error, absolute square error, mean error, root-mean-square standardized error, measured values versus predicted values were used for cross-validation. The overall weighted overlay model result showed that 146 km2 areas are highly suitable, 135 km2 moderately suitable and 60 km2 area unsuitable for irrigation use. The result of irrigation water quality index confirms 10.26% with no restriction, 23.08% with low restriction, 20.51% with moderate restriction, 15.38% with high restriction and 30.76% with the severe restriction for irrigation use. GIS and irrigation water quality index are better methods for irrigation water resources management to achieve a full yield irrigation production to improve food security and to sustain it for a long period, to avoid the possibility of increasing environmental problems for the future generation.

  3. Irrigation methods for efficient water application: 40 years of South ...

    African Journals Online (AJOL)

    The purpose of an irrigation system is to apply the desired amount of water, at the correct application rate and uniformly to the whole field, at the right time, with the least amount of non-beneficial water consumption (losses), and as economically as possible. We know that irrigated agriculture plays a major role in the ...

  4. Root Development of Transplanted Cotton and Simulation of Soil Water Movement under Different Irrigation Methods

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-07-01

    Full Text Available Winter wheat and cotton are the main crops grown on the North China Plain (NCP. Cotton is often transplanted after the winter wheat harvest to solve the competition for cultivated land between winter wheat and cotton, and to ensure that both crops can be harvested on the NCP. However, the root system of transplanted cotton is distorted due to the restrictions of the seedling aperture disk before transplanting. Therefore, the investigation of the deformed root distribution and water uptake in transplanted cotton is essential for simulating soil water movement under different irrigation methods. Thus, a field experiment and a simulation study were conducted during 2013–2015 to explore the deformed roots of transplanted cotton and soil water movement using border irrigation (BI and surface drip irrigation (SDI. The results showed that SDI was conducive to root growth in the shallow root zone (0–30 cm, and that BI was conducive to root growth in the deeper root zone (below 30 cm. SDI is well suited for producing the optimal soil water distribution pattern for the deformed root system of transplanted cotton, and the root system was more developed under SDI than under BI. Comparisons between experimental data and model simulations showed that the HYDRUS-2D model described the soil water content (SWC under different irrigation methods well, with root mean square errors (RMSEs of 0.023 and 0.029 cm3 cm−3 and model efficiencies (EFs of 0.68 and 0.59 for BI and SDI, respectively. Our findings will be very useful for designing an optimal irrigation plan for BI and SDI in transplanted cotton fields, and for promoting the wider use of this planting pattern for cotton transplantation.

  5. Comparison and analysis of empirical equations for soil heat flux for different cropping systems and irrigation methods

    Science.gov (United States)

    Irmak, A.; Singh, Ramesh K.; Walter-Shea, Elizabeth; Verma, S.B.; Suyker, A.E.

    2011-01-01

    We evaluated the performance of four models for estimating soil heat flux density (G) in maize (Zea mays L.) and soybean (Glycine max L.) fields under different irrigation methods (center-pivot irrigated fields at Mead, Nebraska, and subsurface drip irrigated field at Clay Center, Nebraska) and rainfed conditions at Mead. The model estimates were compared against measurements made during growing seasons of 2003, 2004, and 2005 at Mead and during 2005, 2006, and 2007 at Clay Center. We observed a strong relationship between the G and net radiation (Rn) ratio (G/Rn) and the normalized difference vegetation index (NDVI). When a significant portion of the ground was bare soil, G/Rn ranged from 0.15 to 0.30 and decreased with increasing NDVI. In contrast to the NDVI progression, the G/Rn ratio decreased with crop growth and development. The G/Rn ratio for subsurface drip irrigated crops was smaller than for the center-pivot irrigated crops. The seasonal average G was 13.1%, 15.2%, 10.9%, and 12.8% of Rn for irrigated maize, rainfed maize, irrigated soybean, and rainfed soybean, respectively. Statistical analyses of the performance of the four models showed a wide range of variation in G estimation. The root mean square error (RMSE) of predictions ranged from 15 to 81.3 W m-2. Based on the wide range of RMSE, it is recommended that local calibration of the models should be carried out for remote estimation of soil heat flux.

  6. 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.

  7. Comparison of different methods in estimating potential evapotranspiration at Muda Irrigation Scheme of Malaysia

    Directory of Open Access Journals (Sweden)

    Sobri Harun

    2012-04-01

    Full Text Available Evapotranspiration (ET is a complex process in the hydrological cycle that influences the quantity of runoff and thus the irrigation water requirements. Numerous methods have been developed to estimate potential evapotranspiration (PET. Unfortunately, most of the reliable PET methods are parameter rich models and therefore, not feasible for application in data scarce regions. On the other hand, accuracy and reliability of simple PET models vary widely according to regional climate conditions. The objective of the present study was to evaluate the performance of three temperature-based and three radiation-based simple ET methods in estimating historical ET and projecting future ET at Muda Irrigation Scheme at Kedah, Malaysia. The performance was measured by comparing those methods with the parameter intensive Penman-Monteith Method. It was found that radiation based methods gave better performance compared to temperature-based methods in estimation of ET in the study area. Future ET simulated from projected climate data obtained through statistical downscaling technique also showed that radiation-based methods can project closer ET values to that projected by Penman-Monteith Method. It is expected that the study will guide in selecting suitable methods for estimating and projecting ET in accordance to availability of meteorological data.

  8. 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...

  9. 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

  10. 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.

  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. 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 ...

  13. 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

  14. 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....

  15. Effect of Irrigation Method on Yield and Quality of Soybean%灌溉方式对大豆产量及品质的影响

    Institute of Scientific and Technical Information of China (English)

    张丽华; 谭国波; 赵洪祥; 闫伟平; 孟祥盟; 方向前; 边少锋

    2011-01-01

    Soybean are sensitive to soil moisture,in order to study the effect of irrigation methods on yield,quality of soybean and water use efficiency( WUE) ,a field experiment was carried out in 2009 and 2010. Three irrigation methods including conventional furrow irrigation,fixed furrow irrigation and alternative furrow irrigation,and three irrigation amount including 15, 22.5 and 30 mm were used in the test. The results showed that appropriate irrigation could obviously improve WUE and yield of soybean. The soybean yield increased obviously with increase of irrigation amount in 2009 which the rainfall was infrequent. The yield,pods per plant,seeds weights and WUE of alternative furrow irrigation 22. 5 mm were higher than other irrigation combinations. Rainfall mainly focused in July and August in 2010,so irrigation was carried out in September. The yield of irrigation 22.5 and 15 mm was higher than 30 mm and control obviously. The yield of irrigation 22.5 mm was higher than 15 mm obviously. The difference of yield wasn't significant between irrigation 30 mm and control. The difference of yield of different irrigation methods wasn't significant with the same irrigation amount. Pods and seeds per plant and WUE of irrigation 22. 5 mm was extremely significant higher than other irrigation amount. The number of pods and seeds and WUE of alternative furrow irrigation 22. 5 mm was extremely significant higher than other irrigation methods. Irrigation could increase soybean protein content to a certain extent. However,oil content was reduced,but the difference of quality wasn' t significant between irrigation and control. The results of two years experiments showed that alternative furrow irrigation with irrigation amount of 22. 5 mm was the best irrigation combination.%于2009和2010年采取常规灌溉、固定隔沟灌溉和交替隔沟灌溉3种灌溉方式,设置15、22.5和30 mm3

  16. Simulation of temporal and spatial distribution of required irrigation water by crop models and the pan evaporation coefficient method

    Science.gov (United States)

    Yang, Yan-min; Yang, Yonghui; Han, Shu-min; Hu, Yu-kun

    2009-07-01

    Hebei Plain is the most important agricultural belt in North China. Intensive irrigation, low and uneven precipitation have led to severe water shortage on the plain. This study is an attempt to resolve this crucial issue of water shortage for sustainable agricultural production and water resources management. The paper models distributed regional irrigation requirement for a range of cultivated crops on the plain. Classic crop models like DSSAT- wheat/maize and COTTON2K are used in combination with pan-evaporation coefficient method to estimate water requirements for wheat, corn, cotton, fruit-trees and vegetables. The approach is more accurate than the static approach adopted in previous studies. This is because the combination use of crop models and pan-evaporation coefficient method dynamically accounts for irrigation requirement at different growth stages of crops, agronomic practices, and field and climatic conditions. The simulation results show increasing Required Irrigation Amount (RIA) with time. RIA ranges from 5.08×109 m3 to 14.42×109 m3 for the period 1986~2006, with an annual average of 10.6×109 m3. Percent average water use by wheat, fruit trees, vegetable, corn and cotton is 41%, 12%, 12%, 11%, 7% and 17% respectively. RIA for April and May (the period with the highest irrigation water use) is 1.78×109 m3 and 2.41×109 m3 respectively. The counties in the piedmont regions of Mount Taihang have high RIA while the central and eastern regions/counties have low irrigation requirement.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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)

  2. 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

  3. 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...

  4. A Method for Precision Closed-Loop Irrigation Using a Modified PID Control Algorithm

    Science.gov (United States)

    Goodchild, Martin; Kühn, Karl; Jenkins, Malcolm; Burek, Kazimierz; Dutton, Andrew

    2016-04-01

    The benefits of closed-loop irrigation control have been demonstrated in grower trials which show the potential for improved crop yields and resource usage. Managing water use by controlling irrigation in response to soil moisture changes to meet crop water demands is a popular approach but requires knowledge of closed-loop control practice. In theory, to obtain precise closed-loop control of a system it is necessary to characterise every component in the control loop to derive the appropriate controller parameters, i.e. proportional, integral & derivative (PID) parameters in a classic PID controller. In practice this is often difficult to achieve. Empirical methods are employed to estimate the PID parameters by observing how the system performs under open-loop conditions. In this paper we present a modified PID controller, with a constrained integral function, that delivers excellent regulation of soil moisture by supplying the appropriate amount of water to meet the needs of the plant during the diurnal cycle. Furthermore, the modified PID controller responds quickly to changes in environmental conditions, including rainfall events which can result in: controller windup, under-watering and plant stress conditions. The experimental work successfully demonstrates the functionality of a constrained integral PID controller that delivers robust and precise irrigation control. Coir substrate strawberry growing trial data is also presented illustrating soil moisture control and the ability to match water deliver to solar radiation.

  5. Optodynamic Phenomena During Laser-Activated Irrigation Within Root Canals

    Science.gov (United States)

    Lukač, Nejc; Gregorčič, Peter; Jezeršek, Matija

    2016-07-01

    Laser-activated irrigation is a powerful endodontic treatment for smear layer, bacteria, and debris removal from the root canal. In this study, we use shadow photography and the laser-beam-transmission probe to examine the dynamics of laser-induced vapor bubbles inside a root canal model and compare ultrasonic needle irrigation to the laser method. Results confirm important phenomenological differences in the two endodontic methods with the laser method resulting in much deeper irrigation. Observations of simulated debris particles show liquid vorticity effects which in our opinion represents the major cleaning mechanism.

  6. 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...

  7. 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...

  8. Evaluation of Irrigation Methods for Highbush Blueberry. I. Growth and Water Requirements of Young Plants

    Science.gov (United States)

    A study was conducted in a new field of northern highbush blueberry (Vaccinium corymbosum L. 'Elliott') to determine the effects of different irrigation methods on growth and water requirements of uncropped plants during the first 2 years after planting. The plants were grown on mulched, raised beds...

  9. An Easy Method for Drainage of Fluid in Cases of Continuous Irrigation of the Hand

    Science.gov (United States)

    Makhijani, Sumeet

    2016-01-01

    Summary: Description of a novel method to perform continuous irrigation for flexor tenosynovitis in a way that is comfortable for the patient and convenient for nursing staff by placing the hand in the suction pouch of a lithotomy style drape attached to wall suction. PMID:28293498

  10. 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.

  11. 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.

  12. 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

  13. Evaluation of 4% Sodium Hypochlorite in eliminating Enterococcus faecalis from the Root Canal when Used with Three Irrigation Methods: An in vitro Study.

    Science.gov (United States)

    Priyank, Harsh; Pandey, Vinisha; Bagul, Abhishek; Majety, Kishore Kumar; Verma, Parul; Choudhury, Basanta Kumar

    2017-03-01

    Endodontic treatment removes all pathogens, such as Enterococcus faecalis from pulp and root canals. The aim of this study is to assess the usefulness of sodium hypo-chlorite (NaOCl) in removing E. faecalis from the root canal used with three different irrigation methods. This study was conducted on freshly extracted maxillary incisors. After biomechanical preparation, root canals were injected with E. faecalis. Three groups were made which contained 30 teeth in each group; 2 mL of NaOCl solution was used for irrigation followed by agitation with K-files in group I; 2 mL of NaOCl solution was used for irrigation and ultrasonic agitation was done in group II. In group III, an alternate irrigation with NaOCl and 3% hydrogen peroxide was done. The fourth group (control) was irrigated with sterile saline solution. E. fae-calis bacteria were sampled to the root canals with paper points and were transferred to tubes that contained 5 mL of brain heart infusion broth. Tubes were incubated and the presence of broth turbidity was suggestive of bacteria remaining in the root canal. All three groups showed no statistically significant difference. However, difference existed between experimental groups and control groups. The author concluded that all three methods of application of NaOCl were effective in disinfecting the root canal than the saline solution. No single irrigant has 100% efficiency. Thus by this study, a best irrigating solution with maximum properties can be established.

  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. 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...

  16. 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

  17. 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...

  18. 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

  19. 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.

  20. 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...

  1. Evaluation of Different Irrigation Methods for an Apple Orchard Using an Aerial Imaging System

    Directory of Open Access Journals (Sweden)

    Duke M. Bulanon

    2016-06-01

    Full Text Available Regular monitoring and assessment of crops is one of the keys to optimal crop production. This research presents the development of a monitoring system called the Crop Monitoring and Assessment Platform (C-MAP. The C-MAP is composed of an image acquisition unit which is an off-the-shelf unmanned aerial vehicle (UAV equipped with a multispectral camera (near-infrared, green, blue, and an image processing and analysis component. The experimental apple orchard at the Parma Research and Extension Center of the University of Idaho was used as the target for monitoring and evaluation. Five experimental rows of the orchard were randomly treated with five different irrigation methods. An image processing algorithm to detect individual trees was developed to facilitate the analysis of the rows and it was able to detect over 90% of the trees. The image analysis of the experimental rows was based on vegetation indices and results showed that there was a significant difference in the Enhanced Normalized Difference Vegetation Index (ENDVI among the five different irrigation methods. This demonstrates that the C-MAP has very good potential as a monitoring tool for orchard management.

  2. 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...

  3. 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

  4. 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)

  5. 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.

  6. 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

  7. 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%.

  8. 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...

  9. 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

  10. 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

  11. 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...

  12. 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.

  13. 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.

  14. Doses and application methods of Azospirillum brasilense in irrigated upland rice

    Directory of Open Access Journals (Sweden)

    Nayara F. S. Garcia

    Full Text Available ABSTRACT The study was carried out in Selvíria-MS, in the 2011/12 and 2012/13 agricultural years, aiming to evaluate the efficiency of Azospirillum brasilense in nitrogen fixation in upland rice, as a function of doses and application methods of the inoculant containing this diazotrophic bacterium. The experimental design was randomized blocks, arranged in a 4 x 4 factorial scheme, with 4 doses of inoculant (control without inoculation, 100, 200 and 300 mL of the commercial product ha-1 and 4 application methods (seed inoculation, application in the sowing furrow, soil spraying after sowing, and foliar spraying at the beginning of plant tillering, with 4 replicates. During the experiment, the agronomic characteristics, production components and yield of the rice crop were evaluated. It was concluded that the inoculant containing Azospirillum brasilense promotes increase (19% in the yield of upland rice under sprinkler irrigation when used at the dose of 200 mL ha-1, regardless of the application methods.

  15. 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.

  16. 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).

  17. 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

  18. 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...

  19. 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 ...

  20. Issues in irrigation for people with a permanent colostomy: a review.

    Science.gov (United States)

    Varma, Sarah

    Colostomy irrigation is a way of achieving faecal continence and is offered as an alternative method of stoma care management to wearing and emptying a colostomy appliance. This article summarizes an extensive literature review carried out to determine the benefits of irrigation to colostomists and barriers to its uptake. Colostomy irrigation is a method of stoma care management offering 'control' over bowel habit thus assisting the colostomist in the adjustment and adaptation towards their new way of life.

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

    OpenAIRE

    mohammad saeed tadaion; Gholamreza Moafpourian

    2017-01-01

    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 carri...

  2. 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,…

  3. 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.

  4. Middle East Regional Irrigation Management Information Systems project-Some science products

    Science.gov (United States)

    Similarities in the aridity of environments and water scarcity for irrigation allow common approaches to irrigation management problems and research methods in the Southern Great Plains of the United States and the Middle East. Measurement methods involving weighing lysimeters and eddy covariance sy...

  5. 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.

  6. 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.

  7. Automated Irrigation System using Weather Prediction for Efficient Usage of Water Resources

    Science.gov (United States)

    Susmitha, A.; Alakananda, T.; Apoorva, M. L.; Ramesh, T. K.

    2017-08-01

    In agriculture the major problem which farmers face is the water scarcity, so to improve the usage of water one of the irrigation system using drip irrigation which is implemented is “Automated irrigation system with partition facility for effective irrigation of small scale farms” (AISPF). But this method has some drawbacks which can be improved and here we are with a method called “Automated irrigation system using weather prediction for efficient usage of water resources’ (AISWP), it solves the shortcomings of AISPF process. AISWP method helps us to use the available water resources more efficiently by sensing the moisture present in the soil and apart from that it is actually predicting the weather by sensing two parameters temperature and humidity thereby processing the measured values through an algorithm and releasing the water accordingly which is an added feature of AISWP so that water can be efficiently used.

  8. 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

  9. 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.

  10. 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.

  11. Automated irrigation systems for wheat and tomato crops in arid ...

    African Journals Online (AJOL)

    2017-04-02

    Apr 2, 2017 ... Many methods have been described and sensors developed to manage irrigation ... time, and automated irrigation systems based on crop water needs can .... output components, and a software program for decision support.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Relationship between pure Schistosoma haematobium infection in Upper Egypt and irrigation systems. Part 1: methods of study.

    Science.gov (United States)

    Hammam, H M; Allam, F A; Hassanein, F; El-Garby, M T

    1975-01-01

    Four villages in Assiut Governorate were studied. They were matched for availability and time of introduction of medical services, the size of population and the socioeconomic status. One village had a basin system of irrigation. The other three villages had perennial irrigation introduced at different dates. A sketch map of each village was made showing the location of every house and the irrigation channels. Total coverage was intended in Gezirat El-Maabda (with basin irrigation) and Nazza Karar (with perennial irrigation-recently introduced). In El-Ghorayeb and Garf Sarhan (with older systems of perennial irrigation) systematic random samples were studied. The Study included a full, double check clinical examination of urine and stools samples and a social study. Data about educational level and activities that bring the individual in contact with canal water were recorded. Tables showing the age and sex distribution of the total population and the population studied in each village are presented and show validity of the samples taken from the population.

  17. Appendicostomy irrigation for facilitating colonic evacuation in colostomy patients. Preliminary report.

    Science.gov (United States)

    Kotanagi, H; Koyama, K; Sato, Y; Takahashi, K

    1998-08-01

    A method for bowel irrigation through an appendicostomy (antegrade colonic enema) for patients with a left colostomy is described. The appendicostomy is easily constructed without morbidity. Irrigation through the appendicostomy is performed with minimum equipment, uses a small volume of irrigation water, and takes a relatively short time. This may improve colonic evacuation in patients with left colostomy.

  18. Estimation of evapotranspiration rate in irrigated lands using stable isotopes

    Science.gov (United States)

    Umirzakov, Gulomjon; Windhorst, David; Forkutsa, Irina; Brauer, Lutz; Frede, Hans-Georg

    2013-04-01

    Agriculture in the Aral Sea basin is the main consumer of water resources and due to the current agricultural management practices inefficient water usage causes huge losses of freshwater resources. There is huge potential to save water resources in order to reach a more efficient water use in irrigated areas. Therefore, research is required to reveal the mechanisms of hydrological fluxes in irrigated areas. This paper focuses on estimation of evapotranspiration which is one of the crucial components in the water balance of irrigated lands. Our main objective is to estimate the rate of evapotranspiration on irrigated lands and partitioning of evaporation into transpiration using stable isotopes measurements. Experiments has done in 2 different soil types (sandy and sandy loam) irrigated areas in Ferghana Valley (Uzbekistan). Soil samples were collected during the vegetation period. The soil water from these samples was extracted via a cryogenic extraction method and analyzed for the isotopic ratio of the water isotopes (2H and 18O) based on a laser spectroscopy method (DLT 100, Los Gatos USA). Evapotranspiration rates were estimated with Isotope Mass Balance method. The results of evapotranspiration obtained using isotope mass balance method is compared with the results of Catchment Modeling Framework -1D model results which has done in the same area and the same time.

  19. 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.

  20. 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).

  1. 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

  2. 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...

  3. 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)

  4. 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 )

  5. 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.

  6. 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...

  7. 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...

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

    Directory of Open Access Journals (Sweden)

    Ridwan Infandra I.Z.

    2018-01-01

    Full Text Available 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 days, analyzing water used or water permeation automatically through the soil moisture has been raised as the interesting topic. Proposed in this research is the ring irrigation system (RIS which is introduced as an alternative channel for emitters that drip water directly onto the soil at the plant’s root zone where the soil conditions before and after watering can be quickly detected by the sensors. This RIS can be used for the potted plant, green house, or other small farm fields. Product design and development (PDD is applied in this research for assisting the designer to understand and create the RIS prototype properly according to the customer’s requirements where the suggested functions obtained will be added and tested.

  9. Analytical Solution for Optimum Design of Furrow Irrigation Systems

    Science.gov (United States)

    Kiwan, M. E.

    1996-05-01

    An analytical solution for the optimum design of furrow irrigation systems is derived. The non-linear calculus optimization method is used to formulate a general form for designing the optimum system elements under circumstances of maximizing the water application efficiency of the system during irrigation. Different system bases and constraints are considered in the solution. A full irrigation water depth is considered to be achieved at the tail of the furrow line. The solution is based on neglecting the recession and depletion times after off-irrigation. This assumption is valid in the case of open-end (free gradient) furrow systems rather than closed-end (closed dike) systems. Illustrative examples for different systems are presented and the results are compared with the output obtained using an iterative numerical solution method. The final derived solution is expressed as a function of the furrow length ratio (the furrow length to the water travelling distance). The function of water travelling developed by Reddy et al. is considered for reaching the optimum solution. As practical results from the study, the optimum furrow elements for free gradient systems can be estimated to achieve the maximum application efficiency, i.e. furrow length, water inflow rate and cutoff irrigation time.

  10. Water economy in the irrigation of family farmland in arid zones

    International Nuclear Information System (INIS)

    Mhiri, A.; Elloumi, M.J.; Laouini, M.

    1983-01-01

    A simple irrigation technique based on the use of polyethylene bags was developed and tested so as to achieve maximum water economy in family-scale farming in arid zones. It simulates localized irrigation and eliminates water losses due to evaporation and drainage. The method was tried out in the cultivation of tomatoes in glasshouses. In comparison with the control experiment in the field with furrow irrigation, the saving of water was 60%, with a 30% drop in production. There was thus a net improvement in efficiency in the utilization of the irrigation water. (author)

  11. Methods for measurement of electron emission yield under low energy electron-irradiation by collector method and Kelvin probe method

    Energy Technology Data Exchange (ETDEWEB)

    Tondu, Thomas; Belhaj, Mohamed; Inguimbert, Virginie [Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse (France); Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse, France and Fondation STAE, 4 allee Emile Monso, BP 84234-31432, Toulouse Cedex 4 (France); Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse (France)

    2010-09-15

    Secondary electron emission yield of gold under electron impact at normal incidence below 50 eV was investigated by the classical collector method and by the Kelvin probe method. The authors show that biasing a collector to ensure secondary electron collection while keeping the target grounded can lead to primary electron beam perturbations. Thus reliable secondary electron emission yield at low primary electron energy cannot be obtained with a biased collector. The authors present two collector-free methods based on current measurement and on electron pulse surface potential buildup (Kelvin probe method). These methods are consistent, but at very low energy, measurements become sensitive to the earth magnetic field (below 10 eV). For gold, the authors can extrapolate total emission yield at 0 eV to 0.5, while a total electron emission yield of 1 is obtained at 40{+-}1 eV.

  12. Methods for measurement of electron emission yield under low energy electron-irradiation by collector method and Kelvin probe method

    International Nuclear Information System (INIS)

    Tondu, Thomas; Belhaj, Mohamed; Inguimbert, Virginie

    2010-01-01

    Secondary electron emission yield of gold under electron impact at normal incidence below 50 eV was investigated by the classical collector method and by the Kelvin probe method. The authors show that biasing a collector to ensure secondary electron collection while keeping the target grounded can lead to primary electron beam perturbations. Thus reliable secondary electron emission yield at low primary electron energy cannot be obtained with a biased collector. The authors present two collector-free methods based on current measurement and on electron pulse surface potential buildup (Kelvin probe method). These methods are consistent, but at very low energy, measurements become sensitive to the earth magnetic field (below 10 eV). For gold, the authors can extrapolate total emission yield at 0 eV to 0.5, while a total electron emission yield of 1 is obtained at 40±1 eV.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. Effect of Subsurface Irrigation with Porous Clay Capsules on Quantitative and Quality of Grape Plant

    Directory of Open Access Journals (Sweden)

    H. Ghorbani Vaghei

    2016-02-01

    Full Text Available Introduction: Maintaining soil moisture content at about field capacity and reducing water loss in near root zone plays a key role for developing soil and water management programs. Clay pot or porous pipe is a traditional sub-irrigation method and is ideal for many farms in the world’s dry land with small and medium sized farms and gardens and is still used limitedly in dry lands of India, Iran, Pakistan, the Middle East, and Latin-America. Clay capsule is one of porous pipes in sub irrigation that is able to release water in near root zone with self- regulative capacity. Watering occurs only in amounts that the plants actually need (this amount is equal to field capacity and released water in near root zone without electricity or use of an automatic dispenser. Materials and Methods: A study was carried out in 2013 on the experimental field of agriculture faculty of Tarbiat Modares University, to study the effect of two irrigation types on qualitative and quantitative characters in grape production (Vitis vinifera L.. In order to provide the water requirement of grape plant were used porous clay capsules for sub irrigation with height and diameter of 12 cm and 3.5 cm and dripper with Neta film type for drip irrigation, respectively. Porous clay capsules provided from soil science group at Tarbiat Modares University. In this research, the volume of water delivered to grape plants during entire growth period in two different irrigation methods was measured separately with water-meters installed at all laterals. The water consumption, yield production and water use efficiency were evaluated and compared in two drip and porous clay irrigation systems at veraison phonological stages. In the veraison stages, cluster weight, cluster length, solid solution and pH content were measured in grape fruits. Leaf chlorophyll content and leaf water content were also measured in two irrigation systems. Results and Discussion: The results of fruit quality

  2. The Effect of Different Levels of Irrigation and Nitrogen Fertilizer on Yield and Water Use Efficiency of Potato in Subsurface Drip Irrigation

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    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

  3. 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

  4. Coil irrigation in sugar cane (Saccharum officinarum

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    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.

  5. 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.

  6. 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.

  7. 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.

  8. 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...

  9. Improved irrigation for hyphema in the treatment of severe contusion hyphema in 106 cases

    Directory of Open Access Journals (Sweden)

    Qian-Wei Zhu

    2013-09-01

    Full Text Available AIM: To investigate the effect of improved irrigation for hyphema in the treatment of severe contusion hyphema.METHODS: Totally 106 patients with severe contusion hyphema underwent viscoelastican and irrigation for hyphema through tunnel incision with urokinas. RESULTS: The hyphema was clear in all patients but 2 cases were rebleeding. The surgery method was superior to the conventional operation in the aspects of vision, intra-ocular pressure and complication.CONCLUSION:Improved irrigation for hyphema could be extended, the operating methods is simple, safe and effective.

  10. 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.

  11. 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 ...

  12. 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 ...

  13. 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...

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

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-01-01

    Full Text Available A three-year study was conducted to evaluate the effects of different irrigation regimes with saline water on soil salinity, yield and water productivity of carrot as a fall-winter crop under actual commercial-farming conditions in the arid region of Tunisia. Carrot was grown on a sandy soil and surface-irrigated with a water having an ECi of 3.6 dS/m. For the three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Four irrigation methods were based on the use of soil water balance (SWB to estimate irrigation amounts and timing while the fifth consisted of using traditional farmers practices. SWB methods consisted in replacement of cumulated ETc when readily available water is depleted with levels of 100% (FI-100, 80% (DI-80 and 60% (DI-60. FI-100 was considered as full irrigation while DI-80 and DI-60 were considered as deficit irrigation regimes. Regulated deficit irrigation regime where 40% reduction is applied only during ripening stage (FI-DI60 was also used. Farmer method (Farmer consisted in giving fixed amounts of water (25 mm every 7 days from planting till harvest. Results on carrot production and soil salinization are globally consistent between the three-year experiments and shows significant difference between irrigation regimes. Higher soil salinity in the root zone is observed at harvest under DI-60 (3.1, 3.4, 3.9 dS/m, respectively, for the three years and farmer irrigation (3.3, 3.6, 3.9 dS/m treatments compared to FI-100 treatment (2.3, 2.6 and 3.1 dS/m. Relatively low ECe values were also observed under FI-DI60 and DI-80 treatments with respectively (2.7, 3, 3.5 dS/m and (2.5, 2.9, 3.3 dS/m. ECe values under the different irrigation treatments were generally lower than or equal to the EC of irrigation water used. Rainfall received during fall and/or winter periods (57, 26 and 29 mm, respectively, during the three years contributed probably to leaching soluble

  15. Irrigation vs. natural evacuation of left colostomy: a comparative study of 340 patients.

    Science.gov (United States)

    Terranova, O; Sandei, F; Rebuffat, C; Maruotti, R; Bortolozzi, E

    1979-01-01

    A comparative study of two methods of managing left colostomy (irrigation and natural evacuation) was carried out on 340 patients who were examined and interviewed at the Stoma Rehabilitation Clinic of the Institute of Surgical Pathology of the University of Padua. Ninety-two per cent of patients who irrigated their colostomies gained fecal continence. No patient who irrigated his colostomy had any cutaneous problem, and this group had significantly better results in preventing leakage of gas and odors compared with those patients using natural evacuation. For most patients who irrigated, the ability to predict or control bowel movements overcame fears of "being dirty" and related psychological problems. These patients also had more normal social and working lives than did those patients not irrigating their colostomies. Only one patient in our series had a colonic perforation, and any chance of a repeat incident will probably disappear with the cone-shaped catheters now available. The authors conclude that in properly selected patients, irrigation is the method of choice for management of left colostomy.

  16. 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.

  17. 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.

  18. Performances du goutte à goutte enterré pour l’irrigation de jeunes palmiers dattiers

    Directory of Open Access Journals (Sweden)

    R. BOURZIZA

    2017-03-01

    Full Text Available In oasis areas, surface water resources are becoming increasingly scarce. Groundwater resources are often overexploited, and are of poor quality for their high salinity degree. Water conservation and economy have therefore become imperative for better oases durability. If localized irrigation is currently recommended in Morocco for saving water, its use in the sub-desert areas does not keep water safe from high evaporation rates. An alternative to this system would be the use of subsurface drip irrigation. This technique is defined as an application of water under soil surface through drippers, which discharge water at generally similar rates as the surface drip irrigation. As subsurface drip irrigation is a newly introduced technique in Morocco, a better understanding in local conditions of the infiltration process around a buried source, and its impact on plant growth is necessarily required. This study aims to contribute to improving the efficiency of water use by testing the performance of subsurface drip irrigation system, especially in areas where water is a limited resource. The objectives of this research are performance evaluation in arid conditions of the subsurface drip irrigation system for young date palms compared to the surface drip, as well as determining the appropriate method of flow measurement for a buried dripper. In this context, an experimental plot was installed on a farm in the region of Erfoud (Errachidia Province, Southeast Morocco to characterize the respective performances of surface and subsurface drip irrigation on young date palm. Flow measurement to calculate the uniformity of the application of water was done through two methods: a flow measurement of drippers above the surface and another one underground. The latter method has also helped us to estimate losses through evaporation for both irrigation techniques. In addition, in order to compare the effect of two irrigation modes, plants were identified at random

  19. Irrigation Requirement Estimation using MODIS Vegetation Indices and Inverse Biophysical Modeling; A Case Study for Oran, Algeria

    Science.gov (United States)

    Bounoua, L.; Imhoff, M.L.; Franks, S.

    2008-01-01

    Human demand for food influences the water cycle through diversion and extraction of fresh water needed to support agriculture. Future population growth and economic development alone will substantially increase water demand and much of it for agricultural uses. For many semi-arid lands, socio-economic shifts are likely to exacerbate changes in climate as a driver of future water supply and demand. For these areas in particular, where the balance between water supply and demand is fragile, variations in regional climate can have potentially predictable effect on agricultural production. Satellite data and biophysically-based models provide a powerful method to quantify the interactions between local climate, plant growth and water resource requirements. In irrigated agricultural lands, satellite observations indicate high vegetation density while the precipitation amount indicates otherwise. This inconsistency between the observed precipitation and the observed canopy leaf density triggers the possibility that the observed high leaf density is due to an alternate source of water, irrigation. We explore an inverse process approach using observations from the Moderate Resolution Imaging Spectroradiometer (MODIS), climatological data, and the NASA's Simple Biosphere model, SiB2, to quantitatively assess water demand in a semi-arid agricultural land by constraining the carbon and water cycles modeled under both equilibrium (balance between vegetation and prevailing local climate) and nonequilibrium (water added through irrigation) conditions. We postulate that the degree to which irrigated lands vary from equilibrium conditions is related to the amount of irrigation water used. We added water using two distribution methods: The first method adds water on top of the canopy and is a proxy for the traditional spray irrigation. The second method allows water to be applied directly into the soil layer and serves as proxy for drip irrigation. Our approach indicates that over

  20. 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.

  1. 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

  2. Energy indices in irrigated wheat production under conservation and conventional tillage and planting methods

    Directory of Open Access Journals (Sweden)

    S. M Hosseini

    2016-04-01

    Full Text Available Introduction: Conservation tillage system was recommended for soil erosion control in North America for the first time 60 years ago (Wang et al., 2006. Using this tillage system including minimum and zero tillage has been rapidly developed in recent years. Thearea covered by zero tillage in 2006 was 95 million ha all over the world (Dumanski et al., 2006. In addition to saving soil and water resources, conservation tillage system reduces energy consumption and improves energy indices by combining different tillage and planting operations. Results of research conducted in Fars province shows that conservation tillage saves fuel consumption for 77% compared to the conventional system (Afzalinia et al., 2009. Conservation tillage also reduces energy consumption from 23.6 to 42.8% in comparison to the conventional tillage (Rusu, 2005. Since energy indices would be affected by reduced input energies in conservation tillage, this research was conducted to evaluate the effect of different tillage and planting methods on energy inputs and energy indices in irrigated wheat production in Eghlid region. Materials and Methods: This research was performed to evaluate and compare the energy indices in irrigated wheat production under different tillage and planting methods. The study was conducted in the form of a randomized complete block experimental design with five treatments and three replications in Eghlid region. The treatments were included, conventional tillage and seed broadcasting (A, conventional tillage and planting with Machine Barzegar grain drill (B, reduced tillage and seeding with Roto-seeder (C, direct seeding with Jairan Sanaat grain drill (D, and direct seeding with Sfoggia direct drill (E. Experimental plots with 10 by 50 m dimensions were used in this study. Loss crop residues were taken out of the experimental plots and standing crop residues were retained in the plots. In the conventional tillage method, primary tillage was performed

  3. The full financial costs of irrigation services: A discussion on existing ...

    African Journals Online (AJOL)

    Considering water as an economic good entails, among other requisites, properly assessing the cost incurred by supplying and managing the resource, and the required infrastructure thereof. Regarding irrigation, the International Commission for Irrigation and Drainage (ICID) set up a method for assessing the full financial ...

  4. 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

  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. Effect of strategic irrigation on infection of apple scab (Venturia inaequalis)

    DEFF Research Database (Denmark)

    Korsgaard, Maren

    2016-01-01

    Strategic irrigation is a method to prevent Apple scab (Venturia inaequalis). It is performed by irrigating the orchard floor in dry periods during spring, 24 hours before rain forecast. Irrigating the old leaves on the orchard floor will elicit the release of ascospores, but due to the dry trees...... and the dry weather, the ascospores dry out without causing infections. The method relies on the occurrence of dry periods during the period of primary infection from April to mid-June. Experiments were carried out at the University of Copenhagen and in an unsprayed Danish organic orchard in 2014 and 2015....... Apple scab on fruit and leaves was reduced by strategic irrigation in ‘Elshof’ at the University field in both years. In the organic orchard the strategic irrigation reduced the infection of leaves by apple scab and Elsinoe leaf and fruit spot in some cultivars and some years. Studies of the ejection...

  7. 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.

  8. 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.

  9. An optimization model to design and manage subsurface drip irrigation system for alfalfa

    Science.gov (United States)

    Kandelous, M.; Kamai, T.; Vrugt, J. A.; Simunek, J.; Hanson, B.; Hopmans, J. W.

    2010-12-01

    Subsurface drip irrigation (SDI) is one of the most efficient and cost-effective methods for watering alfalfa plants. Lateral installation depth and distance, emitter discharge, and irrigation time and frequency of SDI, in addition to soil and climatic conditions affect alfalfa’s root water uptake and yield. Here we use a multi-objective optimization approach to find optimal SDI strategies. Our approach uses the AMALGAM evolutionary search method, in combination with the HYDRUS-2D unsaturated flow model to maximize water uptake by alfalfa’s plant roots, and minimize loss of irrigation and drainage water to the atmosphere or groundwater. We use a variety of different objective functions to analyze SDI. These criteria include the lateral installation depth and distance, the lateral discharge, irrigation duration, and irrigation frequency. Our framework includes explicit recognition of the soil moisture status during the simulation period to make sure that the top soil is dry for harvesting during the growing season. Initial results show a wide spectrum of optimized SDI strategies for different root distributions, soil textures and climate conditions. The developed tool should be useful in helping farmers optimize their irrigation strategy and design.

  10. 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

  11. [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.

  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. Irrigation port hydration in phacoemulsification surgery

    Directory of Open Access Journals (Sweden)

    Suzuki H

    2018-01-01

    Full Text Available Hisaharu Suzuki,1 Yoichiro Masuda,2 Yuki Hamajima,1 Hiroshi Takahashi3 1Department of Ophthalmology, Nippon Medical School Musashikosugi Hospital, Kawasaki City, Kanagawa, 2Department of Ophthalmology, The Jikei University, Katsushika Medical Center, Tokyo, 3Department of Ophthalmology, Nippon Medical School, Tokyo, Japan Background: In most cases, hydration is performed by water injection into the stromal tissue with a needle. The technique is simple, however it is sometimes troublesome.Purpose: We describe a simple technique for hydrating the corneal stroma in cataract surgery using an irrigation port.Patients and methods: The technique began by pushing the irrigation port against the corneal stroma for a few seconds during phacoemulsification, which generated edema in the corneal incision that subsequently prevented leakage. This procedure is called the hydration using irrigation port (HYUIP technique. A total of 60 eyes were randomized and placed in two groups, 30 eyes underwent surgeries using the HYUIP technique (HYUIP group and 30 eyes underwent surgeries without the HYUIP technique (control. The three points evaluated during each surgery included 1 the occurrence of anterior chamber collapse during the pulling out of the I/A tip after inserting the intraocular lens, 2 the need for conventional hydration, and 3 watertight completion at the end stage of surgery.Results: The anterior chamber collapse and the need for conventional hydration were significantly smaller in the HYUIP group compared to the control group. Regarding the self-sealing completion, no significant difference was observed between the two groups.Conclusion: The HYUIP technique is an effective method for creating self-sealing wound. In addition, this technique helps to prevent anterior chamber collapse. Keywords: cataract surgery, hydration, irrigation and aspiration, phacoemulsification, wound, self-sealing 

  14. 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

  15. 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.

  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. Emergy Evaluation of a Production and Utilization Process of Irrigation Water in China

    Directory of Open Access Journals (Sweden)

    Dan Chen

    2013-01-01

    Full Text Available Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp. and that the transformities of irrigation water and rice as the systems’ products (1.72E+05 sej/J and 1.42E+05 sej/J, resp.; sej/J = solar emjoules per joule represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R, emergy yield ratio (EYR, emergy investment ratio (EIR, environmental load ratio (ELR, and environmental sustainability index (ESI. The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water.

  18. Emergy evaluation of a production and utilization process of irrigation water in China.

    Science.gov (United States)

    Chen, Dan; Luo, Zhao-Hui; Chen, Jing; Kong, Jun; She, Dong-Li

    2013-01-01

    Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp.) and that the transformities of irrigation water and rice as the systems' products (1.72E + 05 sej/J and 1.42E + 05 sej/J, resp.; sej/J = solar emjoules per joule) represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR), and environmental sustainability index (ESI). The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water.

  19. Insufficient irrigation induces peri-implant bone resorption: an in vivo histologic analysis in sheep.

    Science.gov (United States)

    Trisi, Paolo; Berardini, Marco; Falco, Antonello; Podaliri Vulpiani, Michele; Perfetti, Giorgio

    2014-06-01

    To measure in vivo impact of dense bone overheating on implant osseointegration and peri-implant bone resorption comparing different bur irrigation methods vs. no irrigation. Twenty TI-bone implants were inserted in the inferior edge of mandibles of sheep. Different cooling procedures were used in each group: no irrigation (group A), only internal bur irrigation (group B), both internal and external irrigation (group C), and external irrigation (group D). The histomorphometric parameters calculated for each implant were as follows: %cortical bone-implant contact (%CBIC) and %cortical bone volume (%CBV). Friedman's test was applied to test the statistical differences. In group A, we found a huge resorption of cortical bone with %CBIC and %CBV values extremely low. Groups B and C showed mean %CBIC and %BV values higher than other groups The mean %CBV value was significantly different when comparing group B and group C vs. group A (P bone caused massive resorption of the cortical bone and implant failure. Drilling procedures on hard bone need an adequate cooling supply because the bone matrix overheating may induce complete resorption of dense bone around implants. Internal-external irrigation and only internal irrigation showed to be more efficient than other types of cooling methods in preventing bone resorption around implants. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  20. 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

  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. 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

  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. Colostomy irrigation in the elderly. Effective recovery regardless of age.

    Science.gov (United States)

    Venturini, M; Bertelli, G; Forno, G; Grandi, G; Dini, D

    1990-12-01

    One hundred forty elderly cancer outpatients with colostomy in the authors' rehabilitation department were included in an analysis of the feasibility, effectiveness, and safety of periodic irrigation of remaining colon with lukewarm tap water with the aim of regaining full continence. Sixteen patients did not have a sufficiently long remaining bowel (cecostomy, transverse colostomy) and 17 were considered unsuitable to learn the technique because of advanced neoplastic disease with poor life expectancy, intercurrent disease, or stomal problems. One hundred seven patients were proposed to perform the irrigation: 17 refused to do so with the remaining 90 able to learn the method without problems. Nearly all patients achieved full continence for at least 24 hours. Three patients refused to continue, and nine interrupted for minor complications. The median duration of irrigation in the whole group is 257 days (range, 1 to 2669 days): 32 patients have been irrigating from one to five years, and 9 patients for more than 5 years. Based on these results, we recommend irrigation as standard rehabilitative treatment for elderly patients.

  6. 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,

  7. 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

  8. Distribution of the root system of peach palm under drip irrigation

    Directory of Open Access Journals (Sweden)

    Adriano da Silva Lopes

    2014-07-01

    Full Text Available The incorporation of technologies has resulted in increased productivity and the more rational management of peach palm, with irrigation being an important tool for certain regions. Thus, studies leading to proper crop management are extremely important, such as the estimate of the effective depth of the root system, which is indispensable for proper irrigation management. The objective of this study was to evaluate the effects of different irrigation depths, as applied by drip irrigation, on the distribution of the root system of peach palm. This experiment was conducted in Ilha Solteira, São Paulo State, Brazil, with drip irrigation, with the two systems (flow of 0.0023 m3 h-1 consisting of four irrigation treatments corresponding to 0, 50, 100 and 150% of Class ‘A’ pan evaporation. After five years, an analysis of the Bactris gasipaes root system was performed at a distance of 0.0, 0.5 and 1.0 meters from the trunk, collecting sampling at two depths (0.0 to 0.3 m and 0.3 to 0.6 m via the auger method (volumetric analysis. We concluded that the effective depth of the root system used for irrigation management should be a maximum of 0.3 meters.

  9. 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

  10. 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.

  11. 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

  12. A controlled trial of colostomy management by natural evacuation, irrigation and foam enema.

    Science.gov (United States)

    Doran, J; Hardcastle, J D

    1981-10-01

    Twenty patients entered a prospective controlled trial of colostomy management by three techniques--natural evacuation, colostomy irrigation and foam enema. Every patient spent 2 months using each technique. The mean number of colostomy actions weekly was 17 during natural evacuation, 6 during irrigation and 10 with the enema. There was no significant difference in the time taken to manage the colostomy by each technique. Eighteen patients considered that both irrigation and the foam enema improved the quality of their life, and opted to continue with irrigation on completion of the study. There were no major complications during the trial but leakage of foam and an increase in flatus were problems with the foam enema. It is concluded that patients should be made aware of the alternative methods available for colostomy management and be encouraged to use the method of their choice.

  13. 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.

  14. An Investigation of the Basic Physics of Irrigation in Urology and the Role of Automated Pump Irrigation in Cystoscopy

    Directory of Open Access Journals (Sweden)

    Dwayne Chang

    2012-01-01

    Full Text Available Objective. To investigate the effects of height, external pressure, and bladder fullness on the flow rate in continuous, non-continuous cystoscopy and the automated irrigation fluid pumping system (AIFPS. Materials. Each experiment had two 2-litre 0.9% saline bags connected to a continuous, non-continuous cystoscope or AIFPS via irrigation tubing. Other equipment included height-adjustable drip poles, uroflowmetry devices, and model bladders. Methods. In Experiment 1, saline bags were elevated to measure the increment in flow rate. In Experiment 2, saline bags were placed under external pressures to evaluate the effect on flow rate. In Experiment 3, flow rate changes in response to variable bladder fullness were measured. Results. Elevating saline bags caused an increase in flow rates, however the increment slowed down beyond a height of 80 cm. Increase in external pressure on saline bags elevated flow rates, but inconsistently. A fuller bladder led to a decrease in flow rates. In all experiments, the AIFPS posted consistent flow rates. Conclusions. Traditional irrigation systems were susceptible to changes in height of irrigation solution, external pressure application, and bladder fullness thus creating inconsistent flow rates. The AIFPS produced consistent flow rates and was not affected by any of the factors investigated in the study.

  15. [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.

  16. 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

  17. 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

  18. 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.

  19. Clay pot irrigation for tomato (Lycopersicon esculentum Mill production in the north east semiarid region of Ethiopia

    Directory of Open Access Journals (Sweden)

    Kebede Woldetsadik

    2011-06-01

    Full Text Available Water shortage is one of the major constraints for production of horticultural crops in arid and semiarid regions. A field experiment was conducted to determine irrigation water and fertilizer use efficiency, growth and yield of tomato under clay pot irrigation at the experimental site of Sekota Dryland Agricultural Research Center, Lalibela, Ethiopia in 2009/10. The experiment comprised of five treatments including furrow irrigated control and clay pot irrigation with different plant population and fertilization methods, which were arranged in Randomized Complete Block Design with three replications. The highest total and marketable fruit yields were obtained from clay pot irrigation combined with application of nitrogen fertilizer with irrigation water irrespective of difference in plant population. The clay pot irrigation had seasonal water use of up to 143.71 mm, which resulted in significantly higher water use efficiency (33.62 kg m-3 as compared to the furrow irrigation, which had a seasonal water use of 485.50 mm, and a water use efficiency of 6.67 kg m-3. Application of nitrogen fertilizer with irrigation water in clay pots improved fertilizer use efficiency of tomato by up to 52% than band application with furrow or clay pot irrigation. Thus, clay pot irrigation with 33,333 plants ha-1 and nitrogen fertilizer application with irrigation water in clay pots was the best method for increasing the yield of tomato while economizing the use of water and nitrogen fertilizer in a semiarid environment.

  20. Activation of Alkaline Irrigation Fluids in Endodontics

    Directory of Open Access Journals (Sweden)

    Laurence J. Walsh

    2017-10-01

    Full Text Available In conventional endodontic treatment, alkaline solutions of sodium hypochlorite (NaOCl and ethylenediaminetetraacetic acid (EDTA are used in combination to disinfect the root canal system and to eliminate debris and smear layers. An important concept that has emerged over recent years is the use of active physical methods for agitating these fluids to improve their penetration within areas that are not reached by endodontic instruments and to accelerate the chemical actions of these alkaline fluids against planktonic microorganisms, biofilms, soft tissue remnants and smear layers. Ultrasonic agitation and more recently pulsed lasers have emerged as two promising methods for activating endodontic irrigation fluids. Ultrasonic agitation with piezoelectric devices employs a moving tip, while laser agitation uses a stationary tip. Both methods cause cavitation, followed by implosions and shear forces which assist with debridement. Fluid streaming further enhances the activity of the fluids. While agitation enhances performance of irrigants, extrusion of fluids from the root canal during activation is a hazard that must be controlled.

  1. 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

  2. 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 )

  3. Design of a pot experiment to study the effect of irrigation with ...

    African Journals Online (AJOL)

    Municipal water was used to irrigate the control treatment of each soil. .... experiment. RESULTS AND DISCUSSION. Since only ... deeper horizons were considered to be irrelevant. With the ... irrigation water uniformly over the soil surface, the four micro- .... of selected vineyard soils and a critical assessment of methods to.

  4. 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

  5. The future of irrigated agriculture under environmental flow requirements restrictions

    Science.gov (United States)

    Pastor, Amandine; Palazzo, Amanda; Havlik, Petr; Kabat, Pavel; Obersteiner, Michael; Ludwig, Fulco

    2016-04-01

    Water is not an infinite resource and demand from irrigation, household and industry is constantly increasing. This study focused on including global water availability including environmental flow requirements with water withdrawal from irrigation and other sectors at a monthly time-step in the GLOBIOM model. This model allows re-adjustment of land-use allocation, crop management, consumption and international trade. The GLOBIOM model induces an endogenous change in water price depending on water supply and demand. In this study, the focus was on how the inclusion of water resources affects land-use and, in particular, how global change will influence repartition of irrigated and rainfed lands at global scale. We used the climate change scenario including a radiative forcing of 8.5 W/m2 (RCP8.5), the socio-economic scenario (SSP2: middle-of-road), and the environmental flow method based on monthly flow allocation (the Variable Monthly Flow method) with high and low restrictions. Irrigation withdrawals were adjusted to a monthly time-step to account for biophysical water limitations at finer time resolution. Our results show that irrigated land might decrease up to 40% on average depending on the choice of EFR restrictions. Several areas were identified as future hot-spots of water stress such as the Mediterranean and Middle-East regions. Other countries were identified to be in safe position in terms of water stress such as North-European countries. Re-allocation of rainfed and irrigated land might be useful information for land-use planners and water managers at an international level to decide on appropriate legislations on climate change mitigation/adaptation when exposure and sensitivity to climate change is high and/or on adaptation measures to face increasing water demand. For example, some countries are likely to adopt measures to increase their water use efficiencies (irrigation system, soil and water conservation practices) to face water shortages, while

  6. 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.

  7. 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.

  8. 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).

  9. 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)

  10. 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.

  11. The effects of drip line depths and irrigation levels on yield, quality ...

    African Journals Online (AJOL)

    This study was conducted to investigate the effects of different drip irrigation methods and different irrigation levels on yield, quality and water use characteristics of lettuce (Lactuca sativa var. longifolia cv. Lital) cultivated in a solar greenhouse from 07 October 2009 to 03 December 2009 in the Eastern Mediterranean region ...

  12. 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.

  13. Monthly Optimal Reservoirs Operation for Multicrop Deficit Irrigation under Fuzzy Stochastic Uncertainties

    Directory of Open Access Journals (Sweden)

    Liudong Zhang

    2014-01-01

    Full Text Available An uncertain monthly reservoirs operation and multicrop deficit irrigation model was proposed under conjunctive use of underground and surface water for water resources optimization management. The objective is to maximize the total crop yield of the entire irrigation districts. Meanwhile, ecological water remained for the downstream demand. Because of the shortage of water resources, the monthly crop water production function was adopted for multiperiod deficit irrigation management. The model reflects the characteristics of water resources repetitive transformation in typical inland rivers irrigation system. The model was used as an example for water resources optimization management in Shiyang River Basin, China. Uncertainties in reservoir management shown as fuzzy probability were treated through chance-constraint parameter for decision makers. Necessity of dominance (ND was used to analyse the advantages of the method. The optimization results including reservoirs real-time operation policy, deficit irrigation management, and the available water resource allocation could be used to provide decision support for local irrigation management. Besides, the strategies obtained could help with the risk analysis of reservoirs operation stochastically.

  14. 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.

  15. 31 CFR 203.10 - Electronic payment methods.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Electronic payment methods. 203.10... TAX AND LOAN PROGRAM Electronic Federal Tax Payments § 203.10 Electronic payment methods. (a) General. Electronic payment methods for Federal tax payments available under this subpart include ACH debit entries...

  16. 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...

  17. 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

  18. TRANSPORT OF SOLUTES IN THE FIELD AS AFFECTED BY IRRIGATION

    Directory of Open Access Journals (Sweden)

    Alessandro Comegna

    2007-09-01

    Full Text Available This study documents and compares the transport of a conservative solute in near saturated soil profiles under flood and sprinkler irrigation. The experiments were carried out on a clay Vertic-Usthortens soil located near Potenza (Italy. Two 2x2 m2 plots were clipped of their native grass vegetation. After spraying on the surface a Cl- pulse as KCl salt; water was applied in five increments over two months as flood irrigation on the first plot and as sprinkler irrigation on the second one. Chloride resident concentration Cr, was sampled by soil coring at four different days after chemical application. Cr(z,t profiles were analyzed by spatial moment method. The recovered mass of Cl- and location of center of mass were comparable for the two types of irrigation. The spread around the center of mass, however, was higher for the flood-irrigated plot. In the flood-irrigated plot, more mass leached below the depth of 90 cm. The velocity of the center of mass was consistently 10-20% larger than the piston displacement velocity. To evaluate the nature of transport, the Cr(z,t distributions were modelled using quasi-steady solution of convection-dispersion equation(CDE. At the scale of our experiments the profiles of Cl- resident concentration are well-simulated.

  19. New Approaches to Irrigation Scheduling of Vegetables

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. Root activity pattern of banana under irrigated and rain conditions

    International Nuclear Information System (INIS)

    Sobhana, A.; Aravindakshan, M.; Wahid, P.A.

    1989-01-01

    Root morphology by excavation method and root activity pattern by 32 P soil-injection technique have been studied in banana var., Nendran under rainfed/irrigated conditions. The number of roots, length and diameter of roots and dry weight of roots were found to be more for the rainfed banana crop compared to the irrigated. The results of the radiotracer studies indicated that about 60 per cent of the active roots of irrigated banana lie within 20 cm distance and about 90 per cent of the total root activity is found within 40 cm distance from the plant. In the case of rainfed crop about 85 per cent of the active roots were found within a radius of 40 cm around the plant. Active roots were found to be more concentrated at 15 to 30 cm depth under rainfed conditions while the density of active roots was more or less uniform along the profile upto a dpeth of 60 cm in irrigated banana. (author). 4 refs., 3 figs

  2. 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...

  3. 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

  4. Transferability Of DEMETER. A Case Study Of The Irrigation Scheme Of Veiga De Chaves

    Science.gov (United States)

    Baptista, A.; Sousa, V.

    2006-08-01

    DEMETER is a research and demonstration project, designed to assess and demonstrate how the integration of Earth Observation techniques in routine Irrigation Advisory Services can improve efficiency in the use of irrigation water. The objectives of this paper are: (1) to analyze the interest in the feasibility of transferring the DEMETER technology to the irrigation scheme of Chaves: (2) to identify the factors that, in general, favour the usefulness of this technology. The irrigation infrastructure and methods, the size and number of irrigation parcels and the main crops grown at the irrigation scheme of Chaves have been recorded. Also a socio-economic description has been done. Field visits, interviews with the staff of water association, and an inquiry to a sample of 107 farmers were made. The main results are: each farmer pays an area based annual fee, independent of the amount of water used for irrigation; most of the irrigated parcels are of very small size, 0.3 ha in average, mostly irrigated by surface methods; the most representative crops grown are potato, forage maize, and several different horticultural crops; an important part of the production is for self-consumption. The farmers are aging and the new generations prefer other jobs than agriculture. A considerable number of farmers have another job in the nearby cities. The small size of the irrigated parcels limits the use of earth observation technologies to expensive high space resolution images. For the time being, farmers do not feel the need for an irrigation advisory service, manly because there is plenty of water which is not bought proportionally to its use. However, circumstances are changing rapidly and, relatively new for the region, environmental concerns related with irrigation, manly nitrate leaching by excess watering of crops prompts the need for an irrigation advisory service in order to maintain crop production with a more rational use of water. The DEMETER technology could be a

  5. New soil water sensors for irrigation management

    Science.gov (United States)

    Effective irrigation management is key to obtaining the most crop production per unit of water applied and increasing production in the face of competing demands on water resources. Management methods have included calculating crop water needs based on weather station measurements, calculating soil ...

  6. Intracavity lavage and wound irrigation for prevention of surgical site infection

    Science.gov (United States)

    Norman, Gill; Atkinson, Ross A; Smith, Tanya A; Rowlands, Ceri; Rithalia, Amber D; Crosbie, Emma J; Dumville, Jo C

    2017-01-01

    Background Surgical site infections (SSIs) are wound infections that occur after an operative procedure. A preventable complication, they are costly and associated with poorer patient outcomes, increased mortality, morbidity and reoperation rates. Surgical wound irrigation is an intraoperative technique, which may reduce the rate of SSIs through removal of dead or damaged tissue, metabolic waste, and wound exudate. Irrigation can be undertaken prior to wound closure or postoperatively. Intracavity lavage is a similar technique used in operations that expose a bodily cavity; such as procedures on the abdominal cavity and during joint replacement surgery. Objectives To assess the effects of wound irrigation and intracavity lavage on the prevention of surgical site infection (SSI). Search methods In February 2017 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase and EBSCO CINAHL Plus. We also searched three clinical trials registries and references of included studies and relevant systematic reviews. There were no restrictions on language, date of publication or study setting. Selection criteria We included all randomised controlled trials (RCTs) of participants undergoing surgical procedures in which the use of a particular type of intraoperative washout (irrigation or lavage) was the only systematic difference between groups, and in which wounds underwent primary closure. The primary outcomes were SSI and wound dehiscence. Secondary outcomes were mortality, use of systemic antibiotics, antibiotic resistance, adverse events, re-intervention, length of hospital stay, and readmissions. Data collection and analysis Two review authors independently assessed studies for inclusion at each stage. Two review authors also undertook data extraction, assessment of risk of bias and GRADE assessment. We calculated risk ratios or differences in means with 95% confidence intervals where

  7. 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...

  8. 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 ...

  9. 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.

  10. 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.

  11. 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

    Full Text Available Field experiments were conducted on a sandy soil during spring of 2009 and autumn of 2010 in southern Tunisia for evaluating the effects of two drip irrigation methods and three irrigation regimes on soil moisture and salinity, yield and water use efficiency of potato (Solanum tuberosum L.. The surface drip (SDI and subsurface drip (SSDI irrigation methods were used. Irrigation regimes consisted in replacement of cumulated ETc when readily available water is depleted with levels of 100% (FI100, 60% (DI60 and 30% (DI30. FI100 was considered as full irrigation while DI60 and DI30 were considered as deficit irrigation regimes. Well water with an ECi of 7.0 dS/m was used for irrigation. Findings are globally consistent between the two experiments. Results show that soil moisture content and salinity were significantly affected by irrigation treatments and methods. Higher soil moisture content and lower soil salinity were maintained with SSDI than SDI for all irrigation treatments. For both irrigation methods, higher salinity and lower moisture content in the root zone are observed under DI60 and DI30 treatments compared to FI100. Potato yields were highest over two cropping periods for the SSDI method although no significant differences were observed with the SDI. Irrigation regimes resulted in significant difference in both irrigation methods on yield and its components. Yields were highest under FI100. Compared to FI100, considerable reductions in potato yields were observed under DI60 and DI30 deficit treatments resulting from a reduction in tubers number/m² and average tuber weight and size. Water use efficiency (WUE was found to vary significantly among irrigation methods and treatments and varied between 5.9 and 20.5 kg/m3. WUE of SSDI method had generally higher values than SDI. The lowest WUE values were observed for the FI100 treatment, while the highest values were obtained under DI30 treatment for both methods. SSDI method provides

  12. Opportunities for Demand Response in California Agricultural Irrigation: A Scoping Study

    Energy Technology Data Exchange (ETDEWEB)

    Marks, Gary [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wilcox, Edmund [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Olsen, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goli, Sasank [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-02

    California agricultural irrigation consumes more than ten billion kilowatt hours of electricity annually and has significant potential for contributing to a reduction of stress on the grid through demand response, permanent load shifting, and energy efficiency measures. To understand this potential, a scoping study was initiated for the purpose of determining the associated opportunities, potential, and adoption challenges in California agricultural irrigation. The primary research for this study was conducted in two ways. First, data was gathered and parsed from published sources that shed light on where the best opportunities for load shifting and demand response lie within the agricultural irrigation sector. Secondly, a small limited survey was conducted as informal face-to-face interviews with several different California growers to get an idea of their ability and willingness to participate in permanent load shifting and/or demand response programs. Analysis of the data obtained from published sources and the survey reveal demand response and permanent load shifting opportunities by growing region, irrigation source, irrigation method, grower size, and utility coverage. The study examines some solutions for demand response and permanent load shifting in agricultural irrigation, which include adequate irrigation system capacity, automatic controls, variable frequency drives, and the contribution from energy efficiency measures. The study further examines the potential and challenges for grower acceptance of demand response and permanent load shifting in California agricultural irrigation. As part of the examination, the study considers to what extent permanent load shifting, which is already somewhat accepted within the agricultural sector, mitigates the need or benefit of demand response for agricultural irrigation. Recommendations for further study include studies on how to gain grower acceptance of demand response as well as other related studies such as

  13. Irrigation water quality influences heavy metal uptake by willows in biosolids.

    Science.gov (United States)

    Laidlaw, W Scott; Baker, Alan J M; Gregory, David; Arndt, Stefan K

    2015-05-15

    Phytoextraction is an effective method to remediate heavy metal contaminated landscapes but is often applied for single metal contaminants. Plants used for phytoextraction may not always be able to grow in drier environments without irrigation. This study investigated if willows (Salix x reichardtii A. Kerner) can be used for phytoextraction of multiple metals in biosolids, an end-product of the wastewater treatment process, and if irrigation with reclaimed and freshwater influences the extraction process. A plantation of willows was established directly onto a tilled stockpile of metal-contaminated biosolids and irrigated with slightly saline reclaimed water (EC ∼2 dS/cm) at a wastewater processing plant in Victoria, Australia. Biomass was harvested annually and analysed for heavy metal content. Phytoextraction of cadmium, copper, nickel and zinc was benchmarked against freshwater irrigated willows. The minimum irrigation rate of 700 mm per growing season was sufficient for willows to grow and extract metals. Increasing irrigation rates produced no differences in total biomass and also no differences in the extraction of heavy metals. The reclaimed water reduced both the salinity and the acidity of the biosolids significantly within the first 12 months after irrigation commenced and after three seasons the salinity of the biosolids had dropped to metal extraction. Reclaimed water irrigation reduced the biosolid pH and this was associated with reductions of the extraction of Ni and Zn, it did not influence the extraction of Cu and enhanced the phytoextraction of Cd, which was probably related to the high chloride content of the reclaimed water. Our results demonstrate that flood-irrigation with reclaimed water was a successful treatment to grow willows in a dry climate. However, the reclaimed water can also change biosolids properties, which will influence the effectiveness of willows to extract different metals. Copyright © 2015 Elsevier Ltd. All rights

  14. 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...

  15. 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.

  16. Developing a Hybrid Solar/Wind Powered Drip Irrigation System for Dragon Fruit Yield

    Science.gov (United States)

    Widiastuti, I.; Wijayanto, D. S.

    2017-03-01

    Irrigation operations take a large amount of water and energy which impact to total costs of crop production. Development of an efficient irrigation supplying precise amount of water and conserving the use of energy can have benefits not only by reducing the operating costs but also by enhancing the farmland productivity. This article presents an irrigation method that promotes sustainable use of water and energy appropriate for a developing tropical country. It proposes a drip irrigation system supported by a combined solar-wind electric power generation system for efficient use of water in dragon fruit cultivation. The electric power generated is used to drive a water pump filling a storage tank for irrigating a 3000 m2 dragon fruit yield in Nguntoronadi, Wonogiri, Indonesia. In designing the irrigation system, the plant’s water requirement was identified based on the value of reference evapotranspiration of the area. A cost/benefit analysis was performed to evaluate the economic feasibility of the proposed scheme. The installation of this solar and wind drip irrigation helps provide sufficient quantity of water to each plant using renewable energy sources which reduce dependence on fossil fuel.

  17. Willingness to pay for more efficient irrigation techniques in the Lake Karla basin, Greece.

    Science.gov (United States)

    Mylopoulos, Nikitas; Fafoutis, Chrysostomos

    2014-05-01

    Thessaly, the second largest plain of Greece, is an intensively cultivated agricultural region. The intense and widespread agriculture of hydrophilic crops, such as cotton, has led to a remarkable water demand increase, which is usually covered by the overexploitation of groundwater resources. The Lake Karla basin is a prominent example of this unsustainable practice. Competition for the limited available freshwater resources in the Lake Karla basin is expected to increase in the near future as demand for irrigation water increases and drought years are expected to increase due to climate change. Together with the Unions of Agricultural Cooperatives, the Local Organizations of Land Reclamation is planning to introduce more efficient, water saving automated drip irrigation in the area among farmers who currently use non-automated drip irrigation, in order to ensure that these farmers can better cope with drought years and that water will be used more efficiently in crop production. Saving water use in irrigated agriculture is expected to be beneficial to both farmers and the restoration of Lake Karla and its wildlife like plants and birds. The aim of this study is to understand and record the farmers' opinions regarding the use of irrigation water and the restoration of Lake Karla, and to extract valuable conclusions and perform detailed analysis of the criteria for a new irrigation method. A general choice experiment with face-to-face interviews was conducted, using a random sample of 150 open field farmers from the study area. The farmers, who use the non-automated drip irrigation method and their farms are located within the watershed of Lake Karla, were interviewed regarding their willingness to switch to more efficient irrigation techniques, such as automated and controlled drip irrigation.The most important benefits of automated drip irrigation are an increase in crop yield, as plants are given water in a more precise way (based on their needs during the

  18. Can plastic mulching replace irrigation in dryland agriculture?

    Science.gov (United States)

    Wang, L.; Daryanto, S.; Jacinthe, P. A.

    2017-12-01

    Increasing water use efficiency (WUE) is a key strategy to maintaining crops yield without over-exploiting the scarce water resource. Plastic mulching technology for wheat and maize has been commonly used in China, but their effect on yield, soil moisture, evapotranspiration (ET), and WUE has not been compared with traditional irrigation method. Using a meta-analysis approach, we quantitatively examined the efficacy of plastic mulching in comparison with traditional irrigation in dryland agriculture. Our results showed that plastic mulching technique resulted in yield increase comparable to irrigated crops but used 24% less water. By covering the ridges with plastic and channeling rainwater into a very narrow planting zone (furrow), plastic mulching increased WUE and available soil moisture. Higher WUE in plastic-mulched croplands was likely a result of greater proportion of available water being used for transpiration than evaporation. If problems related to production costs and residual plastic pollution could be managed, plastic mulching technology would become a promising strategy for dryland farming in other regions.

  19. 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)

  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. Efficiency of final irrigation of root canal in removal of smear layer

    Directory of Open Access Journals (Sweden)

    Mitić Aleksandar

    2009-01-01

    Full Text Available Introduction A smear layer forms on the root canal walls as the consequence of root instrumentation. The smear layer formed in such a way considerably influences the quality of root obturation and endodontic treatment outcome. Objective The aim of this study was to ultrastructurally analyze the surface of intracanal dentine after removal of the smear layer by the solution of doxycycline, citric acid and detergent Tween-80 (MTAD. Methods The study involved 60 single-rooted, extracted, human teeth divided into four groups. All samples were instrumented by a step-back technique and manual K-files, and rinsed during instrumentation by 2% CHX and H2O2. The first group of samples was exclusively rinsed by CHX and H2O2; in the second group, besides using CHX and H2O2, MTAD solution was used for the final irrigation. The samples which were rinsed by distilled water (+ control and the samples rinsed by 5.25% NaOCl and 17% Na EDTA (-control served as control groups. All samples were observed under the scanning electronic microscope JEOL-JSM-5300. The coronary, middle and apex thirds of the radix region were analyzed. Results The obtained results of the SEM analysis showed that the application of 2% chlorhexidine and hydrogen peroxide did not give clear dentine walls, and the smear layer could not be removed completely. The application of the same combination (CHX and H2O2, added by the final MTAD irrigation solution, led to the efficient removal of the smear layer, while the morphological structure of dentine surface remained unchanged. Statistical analysis showed that canal walls in the experimental group with MTAD as the final irrigation were significantly clearer compared to the control group (p<0.001. Conclusion Based on the obtained results, it can be concluded that MTAD is an efficient solution for the final irrigation of the canal system.

  2. 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.

  3. Studies and Application of Remote Sensing Retrieval Method of Soil Moisture Content in Land Parcel Units in Irrigation Area

    Science.gov (United States)

    Zhu, H.; Zhao, H. L.; Jiang, Y. Z.; Zang, W. B.

    2018-05-01

    Soil moisture is one of the important hydrological elements. Obtaining soil moisture accurately and effectively is of great significance for water resource management in irrigation area. During the process of soil moisture content retrieval with multiremote sensing data, multi- remote sensing data always brings multi-spatial scale problems which results in inconformity of soil moisture content retrieved by remote sensing in different spatial scale. In addition, agricultural water use management has suitable spatial scale of soil moisture information so as to satisfy the demands of dynamic management of water use and water demand in certain unit. We have proposed to use land parcel unit as the minimum unit to do soil moisture content research in agricultural water using area, according to soil characteristics, vegetation coverage characteristics in underlying layer, and hydrological characteristic into the basis of study unit division. We have proposed division method of land parcel units. Based on multi thermal infrared and near infrared remote sensing data, we calculate the ndvi and tvdi index and make a statistical model between the tvdi index and soil moisture of ground monitoring station. Then we move forward to study soil moisture remote sensing retrieval method on land parcel unit scale. And the method has been applied in Hetao irrigation area. Results show that compared with pixel scale the soil moisture content in land parcel unit scale has displayed stronger correlation with true value. Hence, remote sensing retrieval method of soil moisture content in land parcel unit scale has shown good applicability in Hetao irrigation area. We converted the research unit into the scale of land parcel unit. Using the land parcel units with unified crops and soil attributes as the research units more complies with the characteristics of agricultural water areas, avoids the problems such as decomposition of mixed pixels and excessive dependence on high-resolution data

  4. Mapping irrigated areas of Ghana using fusion of 30 m and 250 m resolution remote-sensing data

    Science.gov (United States)

    Gumma, M.K.; Thenkabail, P.S.; Hideto, F.; Nelson, A.; Dheeravath, V.; Busia, D.; Rala, A.

    2011-01-01

    Maps of irrigated areas are essential for Ghana's agricultural development. The goal of this research was to map irrigated agricultural areas and explain methods and protocols using remote sensing. Landsat Enhanced Thematic Mapper (ETM+) data and time-series Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to map irrigated agricultural areas as well as other land use/land cover (LULC) classes, for Ghana. Temporal variations in the normalized difference vegetation index (NDVI) pattern obtained in the LULC class were used to identify irrigated and non-irrigated areas. First, the temporal variations in NDVI pattern were found to be more consistent in long-duration irrigated crops than with short-duration rainfed crops due to more assured water supply for irrigated areas. Second, surface water availability for irrigated areas is dependent on shallow dug-wells (on river banks) and dug-outs (in river bottoms) that affect the timing of crop sowing and growth stages, which was in turn reflected in the seasonal NDVI pattern. A decision tree approach using Landsat 30 m one time data fusion with MODIS 250 m time-series data was adopted to classify, group, and label classes. Finally, classes were tested and verified using ground truth data and national statistics. Fuzzy classification accuracy assessment for the irrigated classes varied between 67 and 93%. An irrigated area derived from remote sensing (32,421 ha) was 20-57% higher than irrigated areas reported by Ghana's Irrigation Development Authority (GIDA). This was because of the uncertainties involved in factors such as: (a) absence of shallow irrigated area statistics in GIDA statistics, (b) non-clarity in the irrigated areas in its use, under-development, and potential for development in GIDA statistics, (c) errors of omissions and commissions in the remote sensing approach, and (d) comparison involving widely varying data types, methods, and approaches used in determining irrigated area statistics

  5. Mapping irrigated lands at 250-m scale by merging MODIS data and National Agricultural Statistics

    Science.gov (United States)

    Pervez, Md Shahriar; Brown, Jesslyn F.

    2010-01-01

    Accurate geospatial information on the extent of irrigated land improves our understanding of agricultural water use, local land surface processes, conservation or depletion of water resources, and components of the hydrologic budget. We have developed a method in a geospatial modeling framework that assimilates irrigation statistics with remotely sensed parameters describing vegetation growth conditions in areas with agricultural land cover to spatially identify irrigated lands at 250-m cell size across the conterminous United States for 2002. The geospatial model result, known as the Moderate Resolution Imaging Spectroradiometer (MODIS) Irrigated Agriculture Dataset (MIrAD-US), identified irrigated lands with reasonable accuracy in California and semiarid Great Plains states with overall accuracies of 92% and 75% and kappa statistics of 0.75 and 0.51, respectively. A quantitative accuracy assessment of MIrAD-US for the eastern region has not yet been conducted, and qualitative assessment shows that model improvements are needed for the humid eastern regions where the distinction in annual peak NDVI between irrigated and non-irrigated crops is minimal and county sizes are relatively small. This modeling approach enables consistent mapping of irrigated lands based upon USDA irrigation statistics and should lead to better understanding of spatial trends in irrigated lands across the conterminous United States. An improved version of the model with revised datasets is planned and will employ 2007 USDA irrigation statistics.

  6. [Influences of micro-irrigation and subsoiling before planting on enzyme activity in soil rhizosphere and summer maize yield.

    Science.gov (United States)

    Zhang, Ming Zhi; Niu, Wen Quan; Xu, Jian; Li, Yuan

    2016-06-01

    In order to explore the influences of micro-irrigation and subsoiling before planting on enzyme activity in soil rhizosphere and summer maize yield, an orthogonal experiment was carried out with three factors of micro-irrigation method, irrigation depth, and subsoiling depth. The factor of irrigation method included surface drip irrigation, subsurface drip irrigation, and moistube-irrigation; three levels of irrigation depth were obtained by controlling the lower limit of soil water content to 50%, 65%, and 80% of field holding capacity, respectively; and three depths of deep subsoiling were 20, 40, and 60 cm. The results showed that the activities of catalase and urease increased first and then decreased, while the activity of phosphatase followed an opposite trend in the growth season of summer maize. Compared with surface drip irrigation and moistube-irrigation, subsurface drip irrigation increased the average soil moisture of 0-80 cm layer by 6.3% and 1.8% in the growth season, respectively. Subsurface drip irrigation could significantly increase soil urease activity, roots volume, and yield of summer maize. With the increase of irrigation level, soil phosphatase activity decreased first and then increased, while urease activity and yield increased first and then decreased. The average soil moisture and root volume all increased in the growth season of summer maize. The increments of yield and root volume from subsoiling of 40 to 20 cm were greater than those from 60 to 40 cm. The highest enzyme activity was obtained with the treatment of subsoiling of 40 cm. In terms of improving water resource use efficiency, nitrogen use efficiency, and crop yield, the best management strategy of summer maize was the combination of subsurface drip irrigation, controlling the lower limit of soil water content to 65% of field holding capacity, and 40 cm subsoiling before planting.

  7. Principles of root water uptake, soil salinity and crop yield for optimizing irrigation management

    International Nuclear Information System (INIS)

    Dirksen, C.

    1983-01-01

    The paper reviews the principles of water and salt transport, root water uptake, crop salt tolerance, water quality, and irrigation methods which should be considered in optimizing irrigation management for sustained, viable agriculture with protection of the quality of land and water resources. In particular, the advantages of high-frequency irrigation at small leaching fractions with closed systems are discussed, for which uptake-weighted mean salinity is expected to correlate best with crop yields. Optimization of irrigation management depends on the scale considered. Non-technical problems which are often much harder to solve than technical problems, may well be most favourable for new projects in developing countries. (author)

  8. 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

  9. Increased malaria transmission around irrigation schemes in Ethiopia and the potential of canal water management for malaria vector control

    OpenAIRE

    Kibret, Solomon; Wilson, G Glenn; Tekie, Habte; Petros, Beyene

    2014-01-01

    Background Irrigation schemes have been blamed for the increase in malaria in many parts of sub-Saharan Africa. However, proper water management could help mitigate malaria around irrigation schemes in this region. This study investigates the link between irrigation and malaria in Central Ethiopia. Methods Larval and adult mosquitoes were collected fortnightly between November 2009 and October 2010 from two irrigated and two non-irrigated (control) villages in the Ziway area, Central Ethiopia...

  10. The synergistic effect of ultrasonic activation and irrigation on Enterococcus faecalis biofilm

    Directory of Open Access Journals (Sweden)

    Abeer A Al-Mahdi

    2016-01-01

    Full Text Available Aim: The aim of this investigation was to compare the efficacy of passive ultrasonic irrigation (PUI with either 2.5% sodium hypochlorite (NaOCl or saline, with that of conventional syringe irrigation on intraradicular Enterococcus faecalis biofilm. Materials and Methods: Biofilms of E. faecalis were established over 21 days in 80 single roots that had undergone biomechanical preparation followed by gamma radiation. Biofilms were treated for 1 min with 2.5% NaOCl/PUI (Group 1, 2.5% NaOCl (Group 2, sterile saline/PUI (Group 3, and sterile saline (Group 4. The positive control (n = 4 was used to confirm the presence of biofilm before various treatments. Additional four samples that served as a negative control were used to confirm the sterility of the samples. Biofilm eradication was evaluated by Colony Forming Unit (CFU quantification and scanning electron microscopy (SEM. Results: The median of CFUs of S1 was significantly higher than that of S2 in all experimental groups. SEM examination showed a significant difference between the positive control and the experimental groups (P < 0.001, with the highest score of biofilm in the positive control group followed by Group 4 and both groups were not statistically significant from each other (P = 0.067. Following various treatments, the highest scores of biofilm were observed in the coronal third and the least were in the apical third. Conclusions: PUI did not increase the effectiveness of NaOCl irrigation on biofilm removal, however, PUI enhanced biofilm disturbance when used with saline. The least mean score of remaining biofilm was in the apical third of all treatment groups compared to other thirds.

  11. 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.

  12. 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

  13. Summary of the Georgia Agricultural Water Conservation and Metering Program and evaluation of methods used to collect and analyze irrigation data in the middle and lower Chattahoochee and Flint River basins, 2004-2010

    Science.gov (United States)

    Torak, Lynn J.; Painter, Jaime A.

    2011-01-01

    between volumes of applied irrigation derived from groundwater and surface water. Analysis of per-acre irrigation depths provided a commonality for comparing irrigation practices across the entire range of field sizes in southern Georgia and indicated underreporting of irrigated acres for some systems. Well-to-pond systems supplied irrigation at depths similar to groundwater and can be combined with groundwater irrigation data for subsequent analyses. Average irrigation depths during 2010 indicated an increase from average irrigation depths during 2008 and 2009, most likely the result of relatively dry conditions during 2010 compared to conditions in 2008 and 2009. Geostatistical models facilitated estimation of irrigation water use for unmetered systems and demonstrated usefulness in redesigning the telemetry network. Geospatial analysis evaluated the ability of the telemetry network to represent annually reported water-meter data and presented an objective, unbiased method for revising the network.

  14. Awareness of Measures for Reducing Health Risk of Using Low-Quality Irrigation Water in Morogoro, Tanzania

    DEFF Research Database (Denmark)

    Mayilla, Winfrida; Magayane, Flavianus; Konradsen, Flemming

    2016-01-01

    The study examined the awareness of farmers, vegetable traders, and consumers on the health risk reduction measures when using low-quality water in irrigated agriculture, and identifies farmers’ perceptions of the effectiveness of the health risk reduction measures. Data collection methods includ...... that health education targeting at specific exposed group and their social-demographic characteristics is the potential measure in raising awareness of the potential health risk reduction measures when using low-quality irrigation water in irrigated agriculture.......The study examined the awareness of farmers, vegetable traders, and consumers on the health risk reduction measures when using low-quality water in irrigated agriculture, and identifies farmers’ perceptions of the effectiveness of the health risk reduction measures. Data collection methods included...... a questionnaire survey with 60 farmers, 60 vegetable traders, and 70 consumers and four focus group discussions. General results show a low level of awareness of the health risk reduction measures in using low-quality irrigation water in all respondents’ categories. However, health protection measures...

  15. The Effect of Irrigation and Nitrogen on Growth Attributes and Chlorophyll Content of Garlic in Line Source Sprinkler Irrigation System

    Directory of Open Access Journals (Sweden)

    rahim motalebifard

    2017-02-01

    Full Text Available Introduction: With 12 million tons production per year, garlic is the fourth important crop in world. In addition to its medical value, it has been used in food industry. The Hamedan province with 1900 ha cultivation area and 38 percent of production is one of the most important garlic area productions in Iran. Few studies on water use and management of garlic exist in the world. Garlic is very sensitive to water deficit especially in tubers initiation and ripening periods. The current research was done because of scarce research on garlic production under water deficit condition in Iran and importance of plant nutrition and nutrients especially nitrogen on garlic production under stressful conditions. Nitrogen is necessary and important element for increasing the yield and quality of garlic. Application of nitrogen increases the growth trend of garlic such as number of leaves, leaf length and plant body. Reports have shown that garlic has high nitrogen requirement, particularly in the early stages of growth. Materials and Methods: This study was conducted for evaluating the combined effects of nitrogen and irrigation on the yield and quality of garlic (Allium sativumL.. The study was performed as a split-block based on randomized complete blocks design with factors of irrigation at four levels (0-3(normal irrigation, 3-6 (slight water deficit, 6-9 (moderate water deficit and 9-12 (sever water deficit meters distance from main line source sprinkler system, nitrogen at four levels (0, 50,100 and 150 kg nitrogen per ha using three replications and line source sprinkler irrigation system. The total water of irrigation levels was measured by boxes that were fixed in meddle of each plot. The statistical analysis of results were performed using themethod described by Hanks (1980. The chlorophyll index was measured using the chlorophyll meter 502 (Minolta, Spain. The chlorophyll a and bwas measured by the method described by Arnon (1946 and Gross (1991

  16. 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 ...

  17. 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.

  18. Assesing the suitability of water for irrigation theoretical and practical approach

    International Nuclear Information System (INIS)

    Hannan, A.; Javad, M.A.; Arif, M.; Rashid, A.

    2006-01-01

    Forced by the surface water shortage and prevalent drought like conditions in the country the farmers have started exploiting groundwater resource. On the other hand, seventy percent of the groundwater being marginal to unfit is a threat to the sustainability of irrigated agriculture. The judicious groundwater exploitation and application has also become imperative in context of ever increasing demographic pressure on soil, crop and water resources. Different classes of irrigation waters established by various research scientists / organizations within the country or abroad are not ultimate under all conditions but these serve as general guidelines. In some cases brackish water requires only minor modification under existing irrigation and ogronomic practices, while in most of the cases it requires major changes regarding type of crops grown, method of water application and the use of soil and water amendments. Therefore, before recommending water for irrigation. Soil characteristics, water management practices, drainage condition of the filed and climatic events must be taken into account as waters generally classified unsuitable for irrigation can be used successfully to grow crops without long term hazardous consequences to crops or soils. This can be attempted simply with the use of improved farming and management practices. Use of brackish water for irrigation may increase the resource base for irrigated agriculture in Pakistan. This article reviews various water classification schemes, salinity-crop yield interrelation with detailed discussion on brackish water application and associated problems. The article also covers a number of management options so as to mitigate the problem and sustain food security in the country. (author)

  19. Soil-pit Method for Distribution and Leaching Loss of Nitrogen in Winter Wheat’s Soil, Weishan Irrigation District

    Science.gov (United States)

    Zhao, Erni; Xu, Lirong; Wang, Rongzhen

    2018-01-01

    Unreasonable application of irrigation and fertilizer will cause the waste of water and nitrogen and environmental pollution. In this paper, a series of soil-pit experiments were carried out to study the distribution and leaching loss of nitrogen in winter wheat’s soil. The results showed that NO3 - concentration at 20-80cm depth mainly responded to fertilizer application at the beginning of field experiment, but the amount of irrigation became the dominant factor with the growth of winter wheat. It is noteworthy that the distribution of NO3 - was mainly affected by the amount of fertilizer applied at the depth of 120-160cm in the whole period of growth of winter wheat. The accumulation position of NH4 + was deepened as the amount of irrigation increased, however, the maximum aggregation depth of ammonium nitrogen was no more than 80cm owing to its poor migration. It can be concluded that the influence of irrigation amount on the concentration of NH4 + in soil solution was more obvious than that of fertilizer. Compared with fertilizer, the amount of irrigation played a leading role in the utilization ratio of nitrogen and the yield of winter wheat. In summary, the best water and fertilizer treatment occurred in No.3 soil-pit, which meant that the middle amount of water and fertilizer could get higher wheat yield and less nitrogen leaching losses in the study area.

  20. 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)

  1. 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.

  2. 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

  3. 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.

  4. [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

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

    African Journals Online (AJOL)

    2016-10-04

    Oct 4, 2016 ... results were obtained from the methods the following critical assumptions were ... system design, irrigation water management and the use of alternative ... to provide decision support regarding pipeline investments. SWIP-E ...

  6. 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

  7. 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.

  8. 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.

  9. 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...

  10. Determination of optimal irrigation rates of agricultural crops under consideration of soil properties and climatic conditions

    Directory of Open Access Journals (Sweden)

    Irakli Kruashvili

    2016-09-01

    Full Text Available In conditions of increasing water shortage, further development of irrigated agriculture production is impossible without improving the methods of cultivation of agricultural crops, primarily irrigation technology. In 2015 the experiment have been conducted on the territory of irrigation farming area of village Tamarisi (Marneuli Municipality, according to which comprehensive study of local climatic and soil conditions were conducted. Received data were used for computation crop water requirements for tomato and melon under the different irrigation treatments. Obtained results have shown the possibility of water use efficiency and obtaining sufficiently high yields of crops that participated in the experiment that became possible in a case of usage of drip irrigation technology in combination with plastic mulch.

  11. Behavior, balance and distribution of sediments within irrigation systems. Application to Pakistan

    International Nuclear Information System (INIS)

    Vabre, Alexandre

    2000-01-01

    This PhD work is part of a research program between Cemagref, CEA and IWMI. It aims at studying the sediment deposition phenomena in irrigation Systems of Pakistan. Indeed, many Systems are subject to an excessive sediment deposition that widely disturbs their functioning. A pragmatic approach of the problem is chosen, and the sediment deposition description is realized through global methods. This choice is done in order to allow the developed methods and tools to be utilized directly by the irrigation managers. A global numerical modeling method (GSM) is proposed. It lies on classical laws of sediment transport but a new formalism is proposed for the expression of the deposition. It's a relationship between the sediment trapping efficiency of a reach and its sediment transport capacity. Also, criteria are defined for the definition of homogeneous reaches in the system. An outline of GSM is implemented on a sediment deposition data set of an actual System in Pakistan (Jamrao). A measurement campaign using radio-activable tracers is then carried out on this site to complete the GSM working data set Also, such a campaign with it only is a description method of the deposition phenomena in the irrigation System. The strength of the modeling approach laws is then tested on another case study of irrigation System in Pakistan (Chashma). The results are very much encouraging because the GSM model could be calibrated and validated on several actual deposition trends with quite moderate errors for such a tool. Also, the constituted data set from the tracer campaign was found minimum and sufficient to implement the GSM. Moreover, it has been possible to use the GSM for irrigation management applications. A design criterion for stable canals is proposed. And the GSM has allowed to identify an hydraulic operational scenario on an irrigation System that decreases the deposition. The perspectives of this work are to test the GSM approach on other data sets and then to

  12. Behavior of durum wheat genotypes under normal irrigation and ...

    African Journals Online (AJOL)

    Behavior of durum wheat genotypes under normal irrigation and drought stress conditions in the greenhouse. ... African Journal of Biotechnology ... Genotypes were grouped in cluster analysis (using Ward's method) based on Yp, Ys and ...

  13. 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

  14. 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.

  15. EVALUATION OF RADIONUCLIDE ACCUMULATION IN SOIL DUE TO LONG-TERM IRRIGATION

    International Nuclear Information System (INIS)

    De Wesley Wu

    2006-01-01

    Radionuclide accumulation in soil due to long-term irrigation is an important part of the model for predicting radiation dose in a long period of time. The model usually assumes an equilibrium condition in soil with a constant irrigation rate, so that radionuclide concentration in soil does not change with time and can be analytically solved. This method is currently being used for the dose assessment in the Yucca Mountain project, which requires evaluating radiation dose for a period of 10,000 years. There are several issues associated with the method: (1) time required for the equilibrium condition, (2) validity of constant irrigation rate, (3) agricultural land use for a long period of time, and (4) variation of a radionuclide concentration in water. These issues are evaluated using a numerical method with a simple model built in the GoldSim software. Some key radionuclides, Tc-99, Np-237, Pu-239, and Am-241 are selected as representative radionuclides. The results indicate that the equilibrium model is acceptable except for a radionuclide that requires long time to accumulate in soil and that its concentration in water changes dramatically with time (i.e. a sharp peak). Then the calculated dose for that radionuclide could be overestimated using the current equilibrium method

  16. 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.

  17. 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.

  18. 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.

  19. Effect of Deficit Irrigation Treatments on Vegetative Characteristics and Quantity and Quality of Golden Delicious Apple

    Directory of Open Access Journals (Sweden)

    I. Arji

    2016-07-01

    Full Text Available Introduction: Since Iran is located in arid and semi-arid region of the world, so consumption and saving of water must be taking into account. Water is often a valuable natural resource, thus proper application methods - for increase water efficiency can be very important. Regulated deficit irrigation (RDI is one of the most important methods to increase water use efficiency and fruit quality. Apple is one of the most important fruit trees from economical point of view. Studies showed that regulated deficit irrigation led to growth reduction in apple trees and sometimes fruit quality increased. The aim of this study was to evaluate the effect deficit irrigation on vegetative growth and fruit quantity and quality of Golden delicious apple trees in Gahvareh region of Kermanshah province. Materials and Methods: This experiment was conducted on 10 years old Golden delicious apple trees in a randomized complete block design with 5 irrigation treatments and three replications during 2006. Three apple trees assigned to each experimental unit. Irrigation treatments were: T1= early deficit irrigation (40% water requirement, T2= early deficit irrigation (60% water requirement, T3= late deficit irrigation (40% water requirement, T4=late deficit irrigation (60% water requirement, T5=control (C (100% water requirement. Early deficit irrigation starts 55 days after full bloom (15th Jun and continued 60 days (16th Aug, while late deficit irrigation starts 115 days after from full bloom (16th Aug and continued 40 days near to harvesting time (23th Sept. Control trees were full irrigated based on water requirement, which calculated based on national water document of Iran and irrigation amount was calculated based on the following formulas: Q=0.0184.L.H3/2 Where Q is volumetric flow rate (liter/Second, L is parshall flume crown length (cm and H is water height (cm. Irrigation time was calculated based on national water document of Iran and volumetric flow rate

  20. 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.

  1. New Concept of Cultivation Using Limited Strip-Tillage with Strip Shallow Irrigation

    Directory of Open Access Journals (Sweden)

    Yazid Ismi Intara

    2014-04-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE Dry land is one of land resources which potentially used for food crop cultivation, especially in the areas which have light to medium technical obstacles. The development of technology to improve soil quality in marginal lands to be productive lands is still widely open for agricultural development in Indonesia. Rooting medium quality can be improved by changing soil tillage method and observing the proper crop irrigation technology. It can be the solution for crop cultivation in clay loam soil. This study aimed to obtain water movement model in a minimally-tilled clay soil with strip shallow irrigation. The concept is limited soil-tillage with strip shallow irrigation method, water supply technique, and crop water requirement. Method used in this study includes developing water movement model (software development in a minimally-tilled clay soil with subsurface irrigation. In the final stages, research also conducted water movement analysis testing apparatus in the laboratory, field validation of the subsurface irrigation performance, and cultivation technique testing to chili pepper growth (Capsicum annuumL.. The development of water movement simulation on a limited strip-tillage with subsurface irrigation uses the concept to quantify the amount of water in the soil. The analysis of movement pattern was demonstrated on contour patterns. It showed that the wetting process can reach depth zone – 5 cm to the rooting zone. It was an important discovery on the development of minimum stripe tillage soil with subsurface irrigation. Specifically, it can be concluded that: the result of fitting by eyes to diffusivity graphic and water content obtained the required parameter values for soil physical properties. It was then simulated on horizontal water movement model on a minimum strip-tillage with strip shallow irrigation /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso

  2. 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...

  3. 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.

  4. Hydrochemical assessment of groundwater used for irrigation in Rumphi and Karonga districts, Northern Malawi

    Science.gov (United States)

    Wanda, Elijah M. M.; Gulula, Lewis C.; Phiri, Ambrose

    Irrigation water quality is an essential component of sustainable agriculture. Irrigation water quality concerns have often been neglected over concerns of quantity in most irrigation projects in Malawi. In this study, a hydrochemical assessment of groundwater was carried out to characterize, classify groundwater and evaluate its suitability for irrigation use in Karonga and Rumphi districts, Northern Malawi. Groundwater samples were collected during wet (January-April 2011) and dry (July-September 2011) seasons from 107 shallow wells and boreholes drilled for rural water supply using standard sampling procedures. The water samples were analysed for pH, major ions, total dissolved solids and electrical conductivity (EC), using standard methods. Multivariate chemometric (such as Kruskal Wallis test), hydrographical methods (i.e. Piper diagram) and PHREEQC geochemical modelling program were used to characterise the groundwater quality. Electrical conductivity, percentage sodium ion (% Na+), residual sodium carbonate (RSC), total dissolved solids (TDS), sodium adsorption ratio (SAR), Kelly’s ratio (KR) and permeability index (PI) were used to evaluate the suitability of water for irrigation. It was established that groundwater is neutral to alkaline and mostly freshwater (TDS management is suggested for sustainable development of the water resources for better plant growth, long-term as well as maintaining human health in the study area.

  5. Evaluation Yield of Sunflower (Farrokh cultivar under Effects of Conventional Deficit Irrigation and Partial Root Zone Drying

    Directory of Open Access Journals (Sweden)

    A. Rezaei Estakhroeih

    2015-06-01

    Full Text Available Water shortage is the most important factors on crop production in the world. Several methods of deficit irrigation are solutions for reduction of irrigation water. To understand the effects of conventional deficit irrigation and partial root zone drying treatments on yield, yield components and water use efficiency of sunflower (Farrokh cultivar, one study was carried out. The research was conducted on Shahid Bahonar University of Kerman in the spring of 2011. A factorial experiment in a randomized complete block design with one control (full irrigation and 18 deficit irrigation treatments in three replications was considered. Deficit irrigation treatments were: conventional deficit irrigation (irrigation with %80, %60 and %40 ETP and partial root zone drying (irrigation with %80, %60 and %40 ETP. Every deficit irrigation treatment was conducted in three growth stage of sunflower (all periods of growth, vegetative growth stage and reproductive growth stage.The results showed that the conventional deficit irrigation treatments (irrigation with 80% ETP in vegetative growth had the highest plant height, leaf area, leaf area index and head diameter. Also, the maximum biological yield equal to49054, maximum grain yield is equal to 9934/3 and maximum oil yield is equal to 2441/2 kg per hectare in the conventional deficit irrigation treatments (irrigation with 80% ETP in vegetative growth occurred.The highest water use efficiency for grain yield is equal to 1/46,forbiological yield equal to7/21 and for dry forage yield is equal 5/7 kilograms per cubic meter of water. According to results,conventional deficit irrigation (irrigation with %80, %60 and %40 ETP is recommended on based.

  6. Prospects for Improving Gravity-Fed Surface Irrigation Systems in Mediterranean European Contexts

    Directory of Open Access Journals (Sweden)

    Daniele Masseroni

    2017-01-01

    Full Text Available Traditionally, most irrigation practices in Southern Europe have been based on gravity-fed surface irrigation systems. Currently, these systems remain a relevant typology in the European Union (EU member states of the Mediterranean areas, where it is often the only sustainable method for farmers due to the small size of agricultural holdings, their reduced capacity and readiness to invest and the low ratio between yield profits and irrigation costs. In the last several years, in response to European and national directives, surface irrigation has garnered increasing attention at the political and bureaucratic levels due to frequent criticisms of its postulated low efficiency and high water wastage. However, these systems commonly provide a number of ecosystem services and nature-based solutions that increase the positive externalities in different rural socio-ecological contexts and often have the potential to extend these services and provide solutions that are compatible with economical sustainability. This study aims to discuss the prospects for new practices and for the rehabilitation and modernization of the gravity-fed surface irrigation systems in EU Mediterranean areas to enhance water efficiency, thus gaining both economic advantages and environmental benefits. The difficulties, stimuli for improvements and peculiarities of the irrigation water management of four rural environments located in Italy, Spain and Portugal were analyzed and compared to the current state of the gravity-fed surface irrigation systems with hypothetical future improvements achievable by innovative technologies and practices. In these different case studies, the current gravity-fed surface irrigation systems have an obsolete regulatory structure; water-use efficiency is not a driving criterion for the management of the conveyance and distribution canal network, and farmers are not yet adequately encouraged to adopt more efficient gravity-fed irrigation practices

  7. 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

  8. 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 ...

  9. 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.

  10. 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

  11. 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

  12. A Tool for the Evaluation of Irrigation Water Quality in the Arid and Semi-Arid Regions

    Directory of Open Access Journals (Sweden)

    Lucia Bortolini

    2018-02-01

    Full Text Available In the Mediterranean arid and semi-arid regions, large amounts of low quality waters could be used for crop irrigation, but the adoption of articulated classifications with too rigid quality limits can often reduce the recoverable quantities of water and make the monitoring of water quality too much expensive. Therefore, an evaluation of irrigation water quality based on only a few crucial parameters, which consider the crop species to be irrigated and the type of irrigation system and management adopted, can be an easy and flexible method for maximizing the reuse of wastewater and low-quality water for agricultural purposes. In this view, an irrigation water quality tool (IWQT was developed to support farmers of arid and semi-arid regions on evaluating the use of low quality water for crop irrigation. The most significant and cheapest parameters of irrigation water quality were identified and clustered in three quality classes according to their effects on crop yield and soil fertility (agronomic quality indicators, human health (hygiene and health quality indicators, and irrigation systems (management quality indicators. According to IWQT parameters, a tool reporting a series of recommendations, including water treatment types, was implemented to guide farmers on the use of low quality irrigation water.

  13. Expansion of urban area and wastewater irrigated rice area in Hyderabad, India

    Science.gov (United States)

    Gumma, K.M.; van, Rooijen D.; Nelson, A.; Thenkabail, P.S.; Aakuraju, Radha V.; Amerasinghe, P.

    2011-01-01

    The goal of this study was to investigate land use changes in urban and peri-urban Hyderabad and their influence on wastewater irrigated rice using Landsat ETM + data and spectral matching techniques. The main source of irrigation water is the Musi River, which collects a large volume of wastewater and stormwater while running through the city. From 1989 to 2002, the wastewater irrigated area along the Musi River increased from 5,213 to 8,939 ha with concurrent expansion of the city boundaries from 22,690 to 42,813 ha and also decreased barren lands and range lands from 86,899 to 66,616 ha. Opportunistic shifts in land use, especially related to wastewater irrigated agriculture, were seen as a response to the demand for fresh vegetables and easy access to markets, exploited mainly by migrant populations. While wastewater irrigated agriculture contributes to income security of marginal groups, it also supplements the food basket of many city dwellers. Landsat ETM + data and advanced methods such as spectral matching techniques are ideal for quantifying urban expansion and associated land use changes, and are useful for urban planners and decision makers alike. ?? 2011 Springer Science+Business Media B.V.

  14. [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.

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. How to expand irrigated land in a sustainable way ?

    Science.gov (United States)

    Pastor, Amandine V.; Ludwig, Fulco; Palazzo, Amanda; Havlik, Petr; Kabat, Pavel

    2015-04-01

    Allocation of agriculture commodities and water resources is subject to changes due to climate change, population increase and changes in dietary patterns. This study focused on including global water availability including environmental flow requirements with water withdrawal from irrigation and other sectors (industry, household and hydropower) at a monthly time-step in the GLOBIOM model. This model allows re-adjustment of land-use allocation, crop management, consumption and international trade. The GLOBIOM model induces an endogenous change in water price depending on water supply and demand. In this study, the focus was on how the inclusion of water resources affects land-use and, in particular, how global change will influence repartition of irrigated and rainfed lands at global scale. We used the climate change scenario including a radiative forcing of 2.6 W/m2 (RCP2.6), the socio-economic scenario (SSP2: middle-of-road), and the environmental flow method based on monthly flow allocation (the Variable Monthly Flow method) with high and low restrictions. Irrigation withdrawals were adjusted to a monthly time-step to account for biophysical water limitations at finer time resolution. Our results show that irrigated land might decrease up to 37% on average depending on the choice of EFR restrictions. Several areas were identified as future hot-spots of water stress such as the Mediterranean and Middle-East regions and parts of South-East Asia where the Water Stress Indicator (WSI) ranges from 0.4 to 1 by 2050. Other countries were identified to be in safe position in terms of water stress such as North-European countries. Some countries such as India expect a significant increase in water demand which might be compensated by an increase in water supply with climate change scenario. Re-allocation of rainfed and irrigated land might be useful information for land-use planners and water managers at an international level to decide on appropriate legislations on

  20. Studying Geographical Distribution Map of Weeds of Irrigated Wheat Fields of Ardabil Province

    Directory of Open Access Journals (Sweden)

    B Soheili

    2013-12-01

    Full Text Available In order to identify the density and abundance of weeds in irrigated wheat fields of Ardabil Province, 76 samples of irrigated wheat fields based on cultivation area from all counties of Ardabil province for six years (2001-2006 were selected. The genus and species of weeds from each sampling fields and their population indices density, frequency and uniformity of each species were calculated by using Thomas method. Geographic coordinates of field (Latitude, Altitude and Elevation were the main coverage and were determined by using GPS. These data were used for producing weed maps using GIS in irrigated wheat fields of Ardabil province. Results showed that bedstraw (Galium tricurnatum, Fumitory(Fumaria vaillantiand wildradish (Raphanus raphanistrum were dominant broad leaf weed species and wild oats (Avena fatua, rye (Secale cereal and mouse foxtail(Alopecurus myosuroides dominant grassy weeds species in irrigated wheat fields of Ardabil province. Bindweed (Convolvulus arvensis, Canada thistle(Cirsium arvenseand Acroptilon repens were the most important disturbing plants prior to harvesting in irrigated wheat fields of Ardabil province.

  1. Determining irrigation distribution uniformity and efficiency for nurseries

    Science.gov (United States)

    R. Thomas Fernandez

    2010-01-01

    A simple method for testing the distribution uniformity of overhead irrigation systems is described. The procedure is described step-by-step along with an example. Other uses of distribution uniformity testing are presented, as well as common situations that affect distribution uniformity and how to alleviate them.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. Innovative technology for colostomy irrigation: assessing the impact on patients.

    Science.gov (United States)

    Pace, S; Manuini, F; Maculotti, D

    2015-10-01

    The main purpose of the trial was to evaluate the opinions expressed by a sample of subjects with permanent colostomy, as a result of the use of a new device designed for the execution of transtomal intestinal irrigation; their feedback was analyzed in relation to the concept of Quality of Life. The device was tested on a sample of 14 colostomized patients (10 men and 4 women, aged between 42 and 77 years) who were used to perform intestinal irrigation procedures independently and routinely, with standard technique. After testing the new device, the patients included in the study were asked to fill out a questionnaire built ad hoc for their situation. The analysis of the data collected led to the following conclusions: 93% of the patients described the new irrigation method as simpler than the standard procedure; the majority of the patients assessed bowel emptying as good; 64% of patients reported excellent comfort experienced during the procedure; the presence of a regulator to adjust the instillation speed of water into the intestinal lumen was considered useful to control the flow of the incoming fluid The use of the device guaranteed: psychological tranquility, minimum manual intervention, full achievement of the expected results and decrease in the issues normally encountered with the standard irrigation method. The practical features of the new device ensure easy and straightforward carrying out of the procedure; this ease of use affects the stomized patient's everyday life by reducing the time of procedure completion, thus positively influencing the perception of the patients' Quality of Life.

  8. Status and Causes of Soil Salinization of Irrigated Agricultural Lands in Southern Baja California,Mexico

    International Nuclear Information System (INIS)

    Endo, T.; Yamamoto, S.; Fujiyama, H.; Honna, T.; Larrinaga, J.A.

    2011-01-01

    Selected farmlands in southern Baja California, Mexico, were surveyed to determine the levels and the causes of salinization/sodication in irrigated agricultural soil. The salt dynamics observed in profiles differed from farm to farm. Low EC and high ph levels were observed in the profiles of sandy fields, because the salt composition of these soils can easily change when salts are leached by irrigation water that contains carbonates of sodium. On the other hand, high levels of salinity and sodicity were observed in the soils of clayey fields. Soil salinization/sodication is complexly interrelated with soil characteristics, the amount and composition of salts in the soil, the quantity and quality of irrigation water applied, and the irrigation methods used. Our findings indicate that irrigation water in Baja California should be supplied at a rate that is sufficient to meet crop requirements without exacerbating salt accumulation.

  9. 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

  10. Comparison of drip, pipe and surge spring root irrigation for Jujube (Ziziphus jujuba Mill. fruit quality in the Loess plateau of China.

    Directory of Open Access Journals (Sweden)

    Qing-Han Gao

    Full Text Available Loess Plateau is a typical rain-fed farming region, facing the threat of drought. Irrigation method is among the most important factors affecting jujube quality. This study investigated the response of Ziziphus jujuba Mill. cv. Lizao quality to three different irrigation methods (drip-, pipe- and surge spring root irrigation combining two water levels (20 m(3/hm(2 and 120 m(3/hm(2. The effects of the trials were evaluated by taking into account the physical-chemical characteristics of jujubes and the antioxidant activity. Concomitant to this, the concentration of some taste-related (viz. glucose, fructose, TSS and malic acid and health-related compounds/parameters (viz. catechin and epicatechin were generally much greater in jujube fruit treated with drip irrigation (120 m(3/hm(2. Different irrigation treatments had no significant effects on antioxidant capacity, total phenolics and proanthocyanidins (except for pipe irrigation 20 m(3/hm(2. The best compromise between quality and irrigation of jujube fruit was achieved with drip irrigation (120 m(3/hm(2.

  11. 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.

  12. Using remote sensing to characterize and compare evapotranspiration from different irrigation regimes in the Smith River Watershed of central Montana

    Science.gov (United States)

    Sando, Thomas R.; Caldwell, Rodney R.; Blasch, Kyle W.

    2017-01-01

    According to the 2005 U.S. Geological Survey national water use compilation, irrigation is the second largest use of fresh water in the United States, accounting for 37%, or 484.48 million cubic meters per day, of total freshwater withdrawal. Accurately estimating the amount of water withdrawals and actual consumptive water use (the difference between water withdrawals and return flow) for irrigation at a regional scale is difficult. Remote sensing methods make it possible to compare actual ET (ETa) rates which can serve as a proxy for consumptive water use from different irrigation regimes at a regional scale in a systematic manner. This study investigates crucial components of water use from irrigation such as the difference of ETa rates from flood- and sprinkler-irrigated fields, spatial variability of ETa within a watershed, and the effect of sprinkler irrigation on the water budget of the study area. The mean accumulated ETa depth for the 1,051 square kilometer study area within the upper Smith River watershed was about 467 mm 30-meter per pixel for the 2007 growing season (April through mid-October). The total accumulated volume of ETa for the study area was about 474.705 million cubic meters. The mean accumulated ETa depth from sprinkler-irrigated land was about 687 mm and from flood-irrigated land was about 621 mm from flood-irrigated land. On average, the ETa rate from sprinkler-irrigated fields was 0.25 mm per day higher than flood-irrigated fields over the growing season. Spatial analysis showed that ETa rates within individual fields of a single crop type that are irrigated with a single method (sprinkler or flood) can vary up to about 8 mm per day. It was estimated that the amount of sprinkler irrigation in 2007 accounted for approximately 3% of the total volume of ETa in the study area. When compared to non-irrigated dryland, sprinkler irrigation increases ETa by about 59 to 82% per unit area.

  13. 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)

  14. 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.

  15. [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.

  16. 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

  17. 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...

  18. 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 ...

  19. Quantification of hydrological fluxes in irrigated lands using isotopes for improved water use efficiency

    International Nuclear Information System (INIS)

    Iqbal, N.; Rafiq, M.; Iqbal, T.; Fazal, M.

    2012-01-01

    For the study of water percolation using stable and radioactive isotopes, two experimental plots each measuring 5m X 5m were prepared at NIAB Agriculture Farm, Faisalabad. One plot was given normal irrigation and the other was irrigated with almost double quantity of water than the first one. Study was carried out on wheat and maize crops during 2007-2010. Infiltration rates were calculated from the solute transport by advection. The infiltration rates were also calculated by the water balance approach using moisture content data obtained by neutron moisture probe and flow simulation approach using software 'HYDRUS 1D'. The moisture in the field with normal irrigation percolated up to 90 cm depth. It percolated up to 160 cm in the field with excess irrigation. Infiltration rates determined by different techniques are given. The infiltration rates varied during whole of the experiment period. The rates were highest right after irrigation and then decreased with increase in time. The maximum and minimum infiltration rates determined by different techniques are given, which shows that average infiltration rates calculated by the four methods in case of excess irrigation range between 0.4 and 0.51 cm/day and are in good agreement. Infiltration rates in case of normal irrigation were determined only by tritium and water balance approach and range between 0.21 and 0.34 cm/day. (orig./A.B.)

  20. 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.

  1. 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...

  2. A user-oriented and quantifiable approach to irrigation design.

    NARCIS (Netherlands)

    Baars, E.; Bastiaansen, A.P.M.; Menenti, M.

    1995-01-01

    A new user-oriented approach is presented to apply marketing research techniques to quantify perceptions, preferences and utility values of farmers. This approach was applied to design an improved water distribution method for an irrigation scheme in Mendoza, Argentina. The approach comprises two

  3. Detection and assessment of flood susceptible irrigation networks in Licab, Nueva Ecija, Philippines using LiDAR DTM

    Science.gov (United States)

    Alberto, R. T.; Hernando, P. J. C.; Tagaca, R. C.; Celestino, A. B.; Palado, G. C.; Camaso, E. E.; Damian, G. B.

    2017-09-01

    Climate change has wide-ranging effects on the environment and socio-economic and related sectors which includes water resources, agriculture and food security, human health, terrestrial ecosystems, coastal zones and biodiversity. Farmers are under pressure to the changing weather and increasing unpredictable water supply. Because of rainfall deficiencies, artificial application of water has been made through irrigation. Irrigation is a basic determinant of agriculture because its inadequacies are the most powerful constraints on the increase of agricultural production. Irrigation networks are permanent and temporary conduits that supply water to agricultural areas from an irrigation source. Detection of irrigation networks using LiDAR DTM, and flood susceptible assessment of irrigation networks could give baseline information on the development and management of sustainable agriculture. Map Gully Depth (MGD) in Whitebox GAT was used to generate the potential irrigation networks. The extracted MGD was overlaid in ArcGIS as guide in the digitization of potential irrigation networks. A flood hazard map was also used to identify the flood susceptible irrigation networks in the study area. The study was assessed through field validation of points which were generated using random sampling method. Results of the study showed that most of the detected irrigation networks have low to moderate susceptibility to flooding while the rest have high susceptibility to flooding which is due to shifting weather. These irrigation networks may cause flood when it overflows that could also bring huge damage to rice and other agricultural areas.

  4. Evaluation of 14 winter bread wheat genotypes in normal irrigation ...

    African Journals Online (AJOL)

    Evaluation of 14 winter bread wheat genotypes in normal irrigation and stress conditions after anthesis stage. ... African Journal of Biotechnology ... Using biplot graphic method, comparison of indices amounts and mean rating of indices for ...

  5. 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.

  6. Effects of Irrigation Methods on the Growth of Petunia Grown in Heat Fusion Polyester Fiber Hardened Medium without Polythylene Pot

    OpenAIRE

    後藤, 丹十郎; 島, 浩二; 東, 千里; 森下, 照久; 藤井, 一徳; 元岡, 茂治

    2006-01-01

    Recenty, polyethylene pots(PP) present a significant environmental issue for waste disposal. To develop bedding plant production system without PP, properties of compacted medium hardened by heat fusion polyester fiber were investigated. Effects of irrigation methods on the growth of vegetative propagated petunia grown in medium without PP were investigated. The effect of medium type was not as significant as the difference in water loss per pot. Water loss per pot of medium without PP was ab...

  7. Purple Phototrophic Bacterium Enhances Stevioside Yield by Stevia rebaudiana Bertoni via Foliar Spray and Rhizosphere Irrigation

    Science.gov (United States)

    Wu, Jing; Wang, Yiming; Lin, Xiangui

    2013-01-01

    This study was conducted to compare the effects of foliar spray and rhizosphere irrigation with purple phototrophic bacteria (PPB) on growth and stevioside (ST) yield of Stevia. rebaudiana. The S. rebaudiana plants were treated by foliar spray, rhizosphere irrigation, and spray plus irrigation with PPB for 10 days, respectively. All treatments enhanced growth of S. rebaudiana, and the foliar method was more efficient than irrigation. Spraying combined with irrigation increased the ST yield plant -1 by 69.2% as compared to the control. The soil dehydrogenase activity, S. rebaudiana shoot biomass, chlorophyll content in new leaves, and soluble sugar in old leaves were affected significantly by S+I treatment, too. The PPB probably works in the rhizosphere by activating the metabolic activity of soil bacteria, and on leaves by excreting phytohormones or enhancing the activity of phyllosphere microorganisms. PMID:23825677

  8. 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)

  9. Use of Dehydrated Agar to Estimate Microbial Water Quality for Horticulture Irrigation.

    Science.gov (United States)

    Meador, Dustin P; Fisher, Paul R; Guy, Charles L; Harmon, Philip F; Peres, Natalia A; Teplitski, Max

    2016-07-01

    Petrifilms are dehydrated agar culture plates that have been used to quantify colony forming units (CFU) mL of either aerobic bacteria (Petrifilm-AC) or fungus (Petrifilm-YM), depending on substrate composition. Microbes in irrigation systems can indicate biofilm risk and potential clogging of irrigation emitters. The research objective was to compare counts on Petrifilms versus traditional, hydrated-agar plates using samples collected from recirculated irrigation waters and cultures of isolated known species. The estimated count (in CFU mL) from a recirculated irrigation sample after 7 d of incubation on Petrifilm-YM was only 5.5% of the count quantified using sabouraud dextrose agar (SDA) with chloramphenicol after 14 d. In a separate experiment with a known species, Petrifilm-YM did not successfully culture zoospores of . Isolates of viable zoospores were cultured successfully on potato-dextrose agar (PDA), with comparable counts with a vegetable juice medium supplemented with the antibiotics pimaricin, ampicillin, rifamycin, pentochloronitrobenzene and hymexazol (PARP-H). The quantification of pv. Begoniaceae on Petrifilm-AC was not significantly different ( < 0.05) than on PDA, but was lower than on Reasoner and Goldrich agar (R2A) or with a hemocytometer. The current formulation of Petrifilm-YM is unlikely to be a useful monitoring method for plant pathogens in irrigation water because of the inability to successfully culture oomycetes. However, Petrifilm-AC was an effective method to quantify bacteria and can provide an easy-to-use on-farm tool to monitor biofilm risk and microbial density. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. Documentation of methods and inventory of irrigation data collected for the 2000 and 2005 U.S. Geological Survey Estimated use of water in the United States, comparison of USGS-compiled irrigation data to other sources, and recommendations for future compilations

    Science.gov (United States)

    Dickens, Jade M.; Forbes, Brandon T.; Cobean, Dylan S.; Tadayon, Saeid

    2011-01-01

    Every five years since 1950, the U.S. Geological Survey (USGS) National Water Use Information Program (NWUIP) has compiled water-use information in the United States and published a circular report titled "Estimated use of water in the United States," which includes estimates of water withdrawals by State, sources of water withdrawals (groundwater or surface water), and water-use category (irrigation, public supply, industrial, thermoelectric, and so forth). This report discusses the impact of important considerations when estimating irrigated acreage and irrigation withdrawals, including estimates of conveyance loss, irrigation-system efficiencies, pasture, horticulture, golf courses, and double cropping.

  11. Effects of different irrigation methods and plant densities on silage quality parameters of PR 31Y43 hybrid corn cultivar (Zea mays L. var. indentata [Sturtev.] L.H. Bailey

    Directory of Open Access Journals (Sweden)

    Muhammet Karasahin

    2014-03-01

    Full Text Available The yield and quality of corn silage is related to genotype as well as factors such as climate, soil conditions, altitude, planting time, plant density, irrigation, and harvesting time. This study was conducted to determine the effects of different irrigation methods (drip, subsoil drip, and subsoil capillary and different plant densities (102 040, 119 040, and 142 850 plant ha-1 on silage quality parameters of PR 31Y43 hybrid corn (Zea mays L. var. indentata [Sturtev.] L.H. Bailey in 2011 and 2012 under ecological conditions in Eskipazar-Karabuk, Turkey. Plant densities were significantly different on fresh ear ratio and plant crude protein (CP yield in both years under study. The highest fresh ear ratio values were obtained with 102 040 and 119 040 plant ha-1 densities and the highest plant CP yield with 142 850 plant ha-1. While the irrigation method x plant density interactions were significant for silage CP ratio in the first year, they were significant on fresh ear ratio in the second year. The highest fresh ear ratio values were obtained from subsoil capillary x 119 040 plant ha-1 and drip x 119 040 plant ha-1 interactions; the highest plant and silage CP ratio values were obtained from subsoil capillary x 142 850 plant ha-1 and subsoil drip x 102 040 plant ha-1 interactions. As a result of the research, high Flieg scores were obtained from each irrigation method and plant density. When plant CP yield is taken into consideration, the 142 850 plant ha-1 density is more important.

  12. Survey of Endodontic Irrigants Used by Dentists With Varying Years of Professional Experience

    Directory of Open Access Journals (Sweden)

    Sharkov Nikolai

    2018-03-01

    Full Text Available Background/Aim: The aim of the present study was to describe the use of irrigants by dentists in Bulgaria in relation to their years of professional experience. Material and Methods: The data were collected with the help of a questionnaire. The survey included questions concerning frequency of irrigants applied, their respective concentrations, as well as spectrum of disinfectants used in endodontics. In addition, information about respondents’ age, years of professional experience, gender, and main areas of continuing education was collected. The statistical analysis was performed with the help of IBM SPSS Statistics 22.0. Results: 219 replies were analysed (response rate 27,3%. The majority of the respondents (31.1% had 21 to 30 years of professional experience. 18.7% had over 30 years. Most of the practitioners reported their continuing education to be in the area of general dentistry - 52%, while about 1.2 % had specialised in endodontics. Dentists with long-standing professional experience use predominantly H2O2 - 78%. Dentists with least experience use 17% EDTA - 53.6%. No significant differences were established for the use of sodium hypochlorite and 2% chlorhexidine. 82% of the respondents use conventional needle 27G for intracanal irrigation; 60% never use ultrasonic irrigation. Conclusions: The analysis of the usage of irrigants shows that many general dental practitioners do not follow the quality recommended protocols for endodontic irrigation protocols.

  13. Groundwater recharge in irrigated semi-arid areas: quantitative hydrological modelling and sensitivity analysis

    Science.gov (United States)

    Jiménez-Martínez, Joaquín; Candela, Lucila; Molinero, Jorge; Tamoh, Karim

    2010-12-01

    For semi-arid regions, methods of assessing aquifer recharge usually consider the potential evapotranspiration. Actual evapotranspiration rates can be below potential rates for long periods of time, even in irrigated systems. Accurate estimations of aquifer recharge in semi-arid areas under irrigated agriculture are essential for sustainable water-resources management. A method to estimate aquifer recharge from irrigated farmland has been tested. The water-balance-modelling approach was based on VisualBALAN v. 2.0, a computer code that simulates water balance in the soil, vadose zone and aquifer. The study was carried out in the Campo de Cartagena (SE Spain) in the period 1999-2008 for three different groups of crops: annual row crops (lettuce and melon), perennial vegetables (artichoke) and fruit trees (citrus). Computed mean-annual-recharge values (from irrigation+precipitation) during the study period were 397 mm for annual row crops, 201 mm for perennial vegetables and 194 mm for fruit trees: 31.4, 20.7 and 20.5% of the total applied water, respectively. The effects of rainfall events on the final recharge were clearly observed, due to the continuously high water content in soil which facilitated the infiltration process. A sensitivity analysis to assess the reliability and uncertainty of recharge estimations was carried out.

  14. Evaluating the effects of mulch and irrigation amount on soil water distribution and root zone water balance using HYDRUS-2D

    Science.gov (United States)

    Drip irrigation under mulch is a major water-saving irrigation method that has been widely practiced for cotton production. The performance of such irrigation systems should be evaluated for proper design, management, operation, and efficient water use. The modeling approach has been used as a commo...

  15. 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.

  16. 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.

  17. Washout resistance of fast-setting pozzolan cement under various root canal irrigants

    Directory of Open Access Journals (Sweden)

    Ga-Yeon Jang

    2013-11-01

    Full Text Available Objectives Fast-setting pozzolan cement (Endocem, Maruchi was recently developed. The aim of this study was to investigate the effects of various root canal irrigants on the washout of Endocem in comparison to the previously marketed mineral trioxide aggregate (ProRoot; Dentsply in a furcal perforation model. Materials and Methods ProRoot and Endocem were placed into acrylic molds on moist Oasis. Each mold was then immediately exposed to either physiologic saline, 2.5% sodium hypochlorite (NaOCl, or 2% chlorhexidine (CHX under gentle shaking for five minutes. Washout testing was performed by scoring scanning electron microscope (SEM images. Results Endocem exhibited higher washout resistance compared to ProRoot, especially in the NaOCl group. Conclusions These results suggest that Endocem can be considered a useful repair material for furcal perforation, especially in a single-visit scenario.

  18. Effects of drought and irrigation on ecosystem functioning in a mature Scots pine forest

    Science.gov (United States)

    Dobbertin, Matthias; Brunner, Ivano; Egli, Simon; Eilmann, Britta; Graf Pannatier, Eisabeth; Schleppi, Patrick; Zingg, Andreas; Rigling, Andreas

    2010-05-01

    Climate change is expected to increase temperature and reduce summer precipitation in Switzerland. To study the expected effects of increased drought in mature forests two different approaches are in general possible: water can be partially or completely removed from the ecosystems via above- or below-canopy roofs or water can be added to already drought-prone ecosystems. Both methods have advantages and disadvantages. In our study water was added to a mature 90-year old Scots pine (Pinus sylvestris L.) forest with a few singe pubescent oaks (Quercus pubescens Willd.), located in the valley bottom of the driest region of Switzerland (Valais). In Valais, Scots pines are declining, usually with increased mortality rates following drought years. It was therefore of special interest to study here how water addition is changing forest ecosystem functioning. The irrigation experiment started in the summer of 2003. Out of eight 0.1 ha experimental plots, four were randomly selected for irrigation, the other four left as a control. Irrigation occurred during rainless nights between April and October, doubling the annual rainfall amount from 650 to 1300 mm. Irrigation water, taken from a near-by irrigation channel, added some nutrients to the plots, but nutrients which were deficient on the site, e.g. nitrogen and phosphorus, were not altered. Tree diameter, tree height and crown width were assessed before the start of the irrigation in winter 2002/2003 and after 7 years of the experiment in 2009/2010. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Additionally, tree mortality was annually evaluated. Mycorrhizal fruit bodies were identified and counted at weekly intervals from 2003 until 2007. Root samples were taken in 2004 and 2005. In 2004 and 2005 wood formation of thirteen trees was analysed in weekly or biweekly intervals using the pinning method. These trees were felled in 2006 for stem, shoot and needle growth analysis

  19. 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.

  20. Assessment of Suitable Areas for Home Gardens for Irrigation Potential, Water Availability, and Water-Lifting Technologies

    Directory of Open Access Journals (Sweden)

    Tewodros Assefa

    2018-04-01

    Full Text Available The study was conducted in Lake Tana Basin of Ethiopia to assess potentially irrigable areas for home gardens, water availability, and feasibility of water-lifting technologies. A GIS-based Multi-Criteria Evaluation (MCE technique was applied to access the potential of surface and groundwater sources for irrigation. The factors affecting irrigation practice were identified and feasibility of water-lifting technologies was evaluated. Pairwise method and expert’s opinion were used to assign weights for each factor. The result showed that about 345,000 ha and 135,000 ha of land were found suitable for irrigation from the surface and groundwater sources, respectively. The rivers could address about 1–1.2% of the irrigable land during dry season without water storage structure whereas groundwater could address about 2.2–2.4% of the irrigable land, both using conventional irrigation techniques. If the seven major dams within the basin were considered, surface water potential would be increased and satisfy about 21% of the irrigable land. If rainwater harvesting techniques were used, about 76% of the basin would be suitable for irrigation. The potential of surface and groundwater was evaluated with respect to water requirements of dominant crops in the region. On the other hand, rope pump and deep well piston hand pump were found with relatively the most (26% and the least (9% applicable low-cost water-lifting technologies in the basin.

  1. 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.

  2. Approaches and challenges of soil water monitoring in an irrigated vineyard

    Science.gov (United States)

    Nolz, Reinhard; Loiskandl, Willibald

    2016-04-01

    Monitoring of water content is an approved method to quantify certain components of the soil water balance, for example as basis for hydrological studies and soil water management. Temporal soil water data also allow controlling water status by means of demand-oriented irrigation. Regarding spatial variability of water content due to soil characteristics, plant water uptake and other non-uniformities, it is a great challenge to select a location that is most likely representing soil water status of a larger area (e.g. an irrigated field). Although such an approach might not satisfy the requirements of precision farming - which becomes more and more related to industrial agriculture - it can help improving water use efficiency of small-scale farming. In this regard, specific conditions can be found in typical vineyards in the eastern part of Austria, where grapes are grown for high quality wine production. Generally, the local dry-subhumid climate supports grape development. However, irrigation is temporarily essential in order to guarantee stable yields and high quality. As the local winegrowers traditionally control irrigation based on their experience, there is a potential to improve irrigation management by means of soil water data. In order to gain experience with regard to irrigation management, soil water status was determined in a small vineyard in Austria (47°48'16'' N, 17°01'57'' E, 118 m elevation). The vineyard was equipped with a subsurface drip irrigation system and access tubes for measuring water content in soil profiles. The latter was measured using a portable device as well as permanently installed multi-sensor capacitance probes. Soil samples were taken at chosen dates and gravimetrically analyzed in the laboratory. Water content data were analyzed using simple statistical procedures and the temporal stability concept. Soil water content was interpreted considering different environmental conditions, including rainfall and irrigation periods

  3. 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.

  4. Drafting method of electricity and electron design

    International Nuclear Information System (INIS)

    Gungbon, Junchun

    1989-11-01

    This book concentrates on drafting of electricity and electron design. It deals with The meaning of electricity and electron drafting JIS standard regulation the types of drafting and line and letter, basics drafting with projection drafting method, plan projection and development elevation, Drafting method of shop drawing, practical method of design and drafting, Design and drafting of technic and illustration, Connection diagram, Drafting of wiring diagram for light and illumination, Drafting of development connection diagram for sequence control, Drafting of logic circuit sign of flow chart and manual, drafting for a electron circuit diagram and Drawing of PC board.

  5. 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.

  6. A simultaneous electron energy and dosimeter calibration method for an electron beam irradiator

    International Nuclear Information System (INIS)

    Tanaka, R.; Sunaga, H.; Kojima, T.

    1991-01-01

    In radiation processing using electron accelerators, the reproducibility of absorbed dose in the product depends not only on the variation of beam current and conveyor speed, but also on variations of other accelerator parameters. This requires routine monitoring of the beam current and the scan width, and also requires periodical calibration of routine dosimeters usually in the shape of film, electron energy, and other radiation field parameters. The electron energy calibration is important especially for food processing. The dose calibration method using partial absorption calorimeters provides only information about absorbed dose. Measurement of average electron current density provides basic information about the radiation field formed by the beam scanning and scattering at the beam window, though it does not allow direct dose calibration. The total absorption calorimeter with a thick absorber allows dose and dosimeter calibration, if the depth profile of relative dose in a reference absorber is given experimentally. It also allows accurate calibration of the average electron energy at the surface of the calorimeter core, if electron fluence received by the calorimeter is measured at the same time. This means that both electron energy and dosimeters can be simultaneously calibrated by irradiation of a combined system including the calorimeter, the detector of the electron current density meter, and a thick reference absorber for depth profile measurement of relative dose. We have developed a simple and multifunctional system using the combined calibration method for 5 MeV electron beams. The paper describes a simultaneous calibration method for electron energy and film dosimeters, and describes the electron current density meter, the total absorption calorimeter, and the characteristics of this method. (author). 13 refs, 7 figs, 3 tabs

  7. Antibacterial Efficacy of a New Sonic Irrigation Device for Root Canal Disinfection.

    Science.gov (United States)

    Neuhaus, Klaus W; Liebi, Melanie; Stauffacher, Simone; Eick, Sigrun; Lussi, Adrian

    2016-12-01

    Passive ultrasonic irrigation (PUI) is the most widespread method used to activate irrigation solutions. Concerns have been raised that PUI is less effective in curved root canals and is not passive at all. Our aim was to compare a novel passive sonic irrigation (PSI) device (6000 Hz) with PUI and manual irrigation (MI) with respect to their efficiency in removing different endodontic microorganisms from curved and straight root canals. We performed 2 experiments as follows. In a 3-day infection model, we included 8 groups of single or dual microbial species that were rinsed with 0.9% sodium chloride using PSI, PUI, or MI. Colony-forming units (CFUs) were counted after incubation, and log 10 transformations were performed for statistical comparisons. In a 21-d infection model, we tested the same irrigation protocols on 4 groups of microorganisms and used 1.5% sodium hypochlorite as an irrigant. Infection control samples were taken at day 0, 3, 5, and 7 after treatment and were subsequently reincubated. Using sodium chloride as an irrigant, the amount of reduction in CFUs compared with the negative control was approximately 3 log 10 units for PSI at 6000 Hz, 2 log 10 units for PUI, and 1 log 10 unit for MI. PSI reduced the microorganism CFUs significantly better than PUI. Using sodium hypochlorite led to a significant reduction in microorganism CFUs even with MI. After 3 days, compared with MI, microorganism regrowth significantly reduced after PSI and PUI treatment, but in these groups, in at least half of the samples, microorganisms were detectable after 7 days. PSI at 6000 Hz might be at least equal to PUI with respect to reduction of the microbial load in curved and straight root canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Decision-making in irrigation networks: Selecting appropriate canal structures using multi-attribute decision analysis.

    Science.gov (United States)

    Hosseinzade, Zeinab; Pagsuyoin, Sheree A; Ponnambalam, Kumaraswamy; Monem, Mohammad J

    2017-12-01

    The stiff competition for water between agriculture and non-agricultural production sectors makes it necessary to have effective management of irrigation networks in farms. However, the process of selecting flow control structures in irrigation networks is highly complex and involves different levels of decision makers. In this paper, we apply multi-attribute decision making (MADM) methodology to develop a decision analysis (DA) framework for evaluating, ranking and selecting check and intake structures for irrigation canals. The DA framework consists of identifying relevant attributes for canal structures, developing a robust scoring system for alternatives, identifying a procedure for data quality control, and identifying a MADM model for the decision analysis. An application is illustrated through an analysis for automation purposes of the Qazvin irrigation network, one of the oldest and most complex irrigation networks in Iran. A survey questionnaire designed based on the decision framework was distributed to experts, managers, and operators of the Qazvin network and to experts from the Ministry of Power in Iran. Five check structures and four intake structures were evaluated. A decision matrix was generated from the average scores collected from the survey, and was subsequently solved using TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) method. To identify the most critical structure attributes for the selection process, optimal attribute weights were calculated using Entropy method. For check structures, results show that the duckbill weir is the preferred structure while the pivot weir is the least preferred. Use of the duckbill weir can potentially address the problem with existing Amil gates where manual intervention is required to regulate water levels during periods of flow extremes. For intake structures, the Neyrpic® gate and constant head orifice are the most and least preferred alternatives, respectively. Some advantages

  9. Effect of irrigation and fertilization on the distribution and fate of nitrogen in greenhouse tomato (solanum lycopersicum l.)

    International Nuclear Information System (INIS)

    Wang, X.; Xing, Y.

    2017-01-01

    A greenhouse experiment using tomato (Solanum lycopersicum L., cv. 'Jinpeng 10') was conducted to investigate the fate and transport of nitrogen using different methods of irrigation and fertilization. Three treatments were designed with two irrigation methods (drip irrigation and furrow irrigation) and two fertilizer application methods (fertigation and conventional fertilization). Tomato fruit yield and biomass in the fertigation treatment were significantly higher than those in the conventional fertilization treatment. The highest total uptake of nitrogen by tomato was obtained with drip fertigation and increased significantly in the conventional fertilization and CK treatments. With an increase in nitrate uptake by the fruit, the uptake of the leaf nitrogen also increased in both years of the study. The distribution of the soil nitrate-N concentration tended to be symmetrical along the center of the emitter for drip irrigation and the furrows. The nitrate-N concentration in the CK treatment was 2.85-fold higher than that in the drip fertigation treatment. The proportion of nitrogen uptake of the total nitrogen input varied from 25.38% and 53.73% in two consecutive years, and the residual nitrogen in the fertigation treatment was 48.20% and 44.64% lower than that in the CK treatment in the same two respective years. (author)

  10. Physiological and biochemical characterization of mango tree with paclobutrazol application via irrigation

    Directory of Open Access Journals (Sweden)

    Moisés Alves de Souza

    2016-12-01

    Full Text Available Paclobutrazol application in mango tree floral induction is followed by changes in the hormonal balance and carbohydrates production. This study aimed at evaluating the physiological and biochemical variables of mango tree (Palmer cultivar by applying paclobutrazol doses via irrigation. The experimental design was randomized blocks, with five paclobutrazol doses (0.7 g, 1.0 g, 1.3 g, 1.6 g and 1.9 g of a.i. per linear meter of canopy and one additional treatment, with one dose in the conventional form of application (1.9 g of a.i. per linear meter of canopy, and four replicates. The variables analyzed were: photosynthesis rate; stomatal conductance; transpiration; leaf temperature; CO2 ratio; total protein content; reducing, non-reducing and total soluble sugars in leaf tissue and fruit; and nitrate reductase enzyme. The lowest values for photosynthesis rate and stomatal conductance were obtained with paclobutrazol applied via irrigation. The highest values for gas exchange were obtained with the lowest paclobutrazol doses applied via irrigation, showing that this kind of application is efficient and that it is possible to reduce the application dose via irrigation system. The highest carbohydrate contents in the leaf tissue were observed for the doses of 1.06 g and 1.09 g of a.i. per linear meter of canopy, applied via irrigation. The carbohydrate contents in fruits decreased in response to the paclobutrazol dose. The application methods and doses applied via irrigation did not influence the nitrate reductase activity.

  11. 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

  12. Classification of irrigated land using satellite imagery, the High Plains aquifer, nominal date 1992

    Science.gov (United States)

    Qi, Sharon L.; Konduris, Alexandria; Litke, David W.; Dupree, Jean

    2002-01-01

    Satellite imagery from the Landsat Thematic Mapper (nominal date 1992) was used to classify and map the location of irrigated land across the High Plains aquifer. The High Plains aquifer underlies 174,000 square miles in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The U.S. Geological Survey is conducting a waterquality study of the High Plains aquifer as part of the National Water-Quality Assessment Program. To help interpret data and select sites for the study, it is helpful to know the location of irrigated land within the study area. To date, the only information available for the entire area is 20 years old. To update the data on irrigated land, 40 summer and 40 spring images (nominal date 1992) were acquired from the National Land Cover Data set and processed using a band-ratio method (Landsat Thematic Mapper band 4 divided by band 3) to enhance the vegetation signatures. The study area was divided into nine subregions with similar environmental characteristics, and a band-ratio threshold was selected from imagery in each subregion that differentiated the cutoff between irrigated and nonirrigated land. The classified images for each subregion were mosaicked to produce an irrigated land map for the study area. The total amount of irrigated land classified from the 1992 imagery was 13.1 million acres, or about 12 percent of the total land in the High Plains. This estimate is approximately 1.5 percent greater than the amount of irrigated land reported in the 1992 Census of Agriculture (12.8 millions acres). This information was also compared to a similar data set based on 1980 imagery. The 1980 data classified 13.7 million acres as irrigated. Although the change in the amount of irrigated land between the two times was not substantial, the location of the irrigated land did shift from areas where there were large ground-water-level declines to other areas where ground-water levels were static or rising.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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...

  19. 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

  20. 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.

  1. 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 ...

  2. 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.

  3. 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.

  4. Studying Geographical Distribution Map of Weeds of Irrigated Wheat Fields of Ardabil Province

    OpenAIRE

    B Soheili

    2013-01-01

    In order to identify the density and abundance of weeds in irrigated wheat fields of Ardabil Province, 76 samples of irrigated wheat fields based on cultivation area from all counties of Ardabil province for six years (2001-2006) were selected. The genus and species of weeds from each sampling fields and their population indices density, frequency and uniformity of each species were calculated by using Thomas method. Geographic coordinates of field (Latitude, Altitude and Elevation) were the ...

  5. 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

  6. 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.

  7. Effect of Regulated Deficit Irrigation (RDI and Partial Root zone Drying (PRD on Quantitative and Qualitative Traits of Strawberry

    Directory of Open Access Journals (Sweden)

    A. Shahnazari

    2016-02-01

    Full Text Available Introduction: Deficit irrigation (DI is a suitable solution to gain acceptable and economic performance by using minimum amount of water. The partial root zone drying (PRD method introduced in Australia for the first time and its goal was controlling the vine’s excessive growth. This goal gained by alternative drying the rootzone. Basically the theory of PRD method, is expanding the plant’s roots by applying alternative stress on different sides of the roots. So the plants with PRD irrigation method can have different root system in comparison with other irrigation methods. At this method the plant’s condition would be OK by uptaking water from wet side, and the roots at the dry side can release abscisic acid hormone which decrease the stomatal conductance and consequently the water use efficiency would be increase.There had been studies on the effect of water tension on strawberry. The previous studies on strawberry indicated that the water stress can increase the plant’s brix concentration and some of plant acids.The awareness of the impact of water deficit stress on strawberry plant quantity and quality is essential for irrigation and product management, and at the current study, effect of different deficit irrigation methods on quantitative and qualitative traits of strawberry have been evaluated. The focus at the current study was on the qualitative traits. Materials and Methods: The present study was conducted in one of strawberry farms of Babolsar city in 2012 to evaluate the effects of deficit irrigation and partial root zone drying on quantitative and qualitative traits of strawberry plants. Three Irrigation treatments were studied: Full Irrigation (FI, Regulated Deficit Irrigation (RDI75% at 75% level of plants water requirementand Partial Root zone Drying (PRD75% at 75% level of plants water requirement. The study was conducted in a randomized complete block design with three replications. Irrigation was continued until the

  8. 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.

  9. Performance of cotton crop grown under surface irrigation and drip fertigation. I. seed cotton yield, dry matter production, and lint properties

    International Nuclear Information System (INIS)

    Janat, M.; Somi, G.

    2002-01-01

    Drip fertigation is a key factor in modern irrigated agriculture, where water and fertilizers are the most expensive inputs for this irrigation method. Drip fertigation experiments were carried out a Hama, north of Syria (Tezeen's Irrigation Research Station), for four consecutive years 1995 - 1998. Cotton (Gossypium hirsutim L.) variety Aleppo 33/1 was planted after unfertilized maize in order to deplete as much as possible the available N and reduce the field variability on the corresponding experimental units and irrigated thereafter. Treatments consisted of two irrigation methods (Surface irrigation and drip fertigation) and five N rates within drip fertigated cotton, including the control (N 0 = 0, N 1 = 60, N 2 = 120, N 3 = 180, N 4 240 kg N ha -1 ). The N fertilizer treatment for surface irrigated cotton was 180 kg N ha -1 in accordance with the recommended rate of ministry of Agriculture and Agrarian Reform. The experimental design was randomized block design with six replicates. Fertigation resulted in large water saving, and highly improved field water-use efficiency. Further, increasing N application rates under drip fertigation increased dry matter yield. The principal benefit of drip fertigation was the achievement of higher field water-use efficiencies, which were increased more than three-fold for both dry matter and seed cotton yield, relative to surface irrigation. The highest water-use efficiencies were obtained with the addition of 180 and 240 kg N ha -1 in 1995 and 1996 and 120 kg N ha -1 in 1997 and 1998. Dry matter production and partitioning among different plant parts at physiological maturity stage varied due to N input and irrigation methods. The overall dry matter distribution among different plant structures for drip fertigated-treatments was: Stems, 20.3 - 21.3%; leaves 26.3 - 28.7%; and fruiting forms, 50 - 53.2%. For the surface-irrigated treatment, the partitioning was stems, 23.1%; leaves, 28.3%; and fruiting form, 48.6%. The

  10. 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

  11. The limit of irrigation adaption due to the inter-crop conflict of water use under changing climate and landuse

    Science.gov (United States)

    Okada, M.; Iizumi, T.; Sakamoto, T.; Kotoku, M.; Sakurai, G.; Nishimori, M.

    2017-12-01

    Replacing rainfed cropping system by irrigated one is assumed to be an effective measure for climate change adaptation in agriculture. However, in many agricultural impact assessments, future irrigation scenarios are externally given and do not consider variations in the availability of irrigation water under changing climate and land use. Therefore, we assess the potential effects of adaption measure expanding irrigated area under climate change by using a large-scale crop-river coupled model, CROVER [Okada et al. 2015, JAMES]. The CROVER model simulates the large-scale terrestrial hydrological cycle and crop growth depending on climate, soil properties, landuse, crop cultivation management, socio-economic water demand, and reservoir operation management. The bias-corrected GCMs outputs under the RCP 8.5 scenario were used. The future expansion of irrigation area was estimated by using the extrapolation method based on the historical change in irrigated and rainfed areas. As the results, the irrigation adaptation has only a limited effect on the rice production in East Asia due to the conflict of water use for irrigation with the other crops, whose farmlands require unsustainable water extraction with the excessively expanding irrigated area. In contrast, the irrigation adaptation benefits maize production in Europe due to the little conflict of water use for irrigation. Our findings suggest the importance of simulating the river water availability and crop production in a single model for the more realistic assessment in the irrigation adaptation potential effects of crop production under changing climate and land use.

  12. Irrigation water quality of Al-Gharraf Canal, south of Iraq

    Science.gov (United States)

    Hussein Ewaid, Salam

    2018-05-01

    To evaluate the water quality of Al-Gharraf Canal south of Iraq for irrigation purpose, analysis of 12 physiochemical parameters of water samples by standard methods was carried out at five stations during the year 2016 (water temperature, pH, electrical conductivity, total dissolved solids, bicarbonate, chloride, calcium, magnesium, sulfate, nitrate, sodium, potassium). Seven irrigation water quality indices were calculated like; sodium percentage (% Na), soluble sodium percentage (SSP), residual sodium bicarbonate (RSBC), Kelly’s ratio (KR), permeability index (PI), magnesium adsorption ratio (MAR), and sodium adsorption ratio (SAR). The results represented as diagrams (Piper, Stiff, Schoeller, Durov, Gibbs, and Wilcox) using AquaChem and RockWork hydro-chemical software. Chemical analysis for canal water demonstrates the calcic chlorinated water type, the dominance of alkalis water, the major cations was in the order of: Na+ > Ca2+ > K+ > Mg2+ and major anions was: Cl- > SO42- > HCO3- > NO3-, the mean values of the irrigation water quality indices were (in meq/l) were; SAR (2.37), % Na (43.4), PI (%) (52.3), SSP (% (38.1), MAR (%) (34.5), KR (0.61), RSBC (-1.78). The results indicate the suitability of canal water for irrigational purposes based on the calculated indices for the majority of crops under special management for salinity and permeability control. The presentation of chemical analysis by diagrams and numbers makes understanding of complex water system too simpler and quicker. This study is a comprehensive assessment towards providing indicators and classification indices on irrigation water quality of the canal ecosystem, which will be the basis for future planning decisions on agricultural demand management measures and water quality monitoring to protect this principal water resource.

  13. [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.

  14. 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

  15. 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...

  16. 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...

  17. 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

  18. 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

  19. 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 ...

  20. 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.

  1. Irrigation management and phosphorus addition alter the abundance of carbon dioxide-fixing autotrophs in phosphorus-limited paddy soil.

    Science.gov (United States)

    Wu, Xiaohong; Ge, Tida; Yan, Wende; Zhou, Juan; Wei, Xiaomeng; Chen, Liang; Chen, Xiangbi; Nannipieri, Paolo; Wu, Jinshui

    2017-12-01

    In this study, we assessed the interactive effects of phosphorus (P) application and irrigation methods on the abundances of marker genes (cbbL, cbbM, accA and aclB) of CO2-fixing autotrophs. We conducted rice-microcosm experiments using a P-limited paddy soil, with and without the addition of P fertiliser (P-treated-pot (P) versus control pot (CK)), and using two irrigation methods, namely alternate wetting and drying (AWD) and continuous flooding (CF). The abundances of bacterial 16S rRNA, archaeal 16S rRNA, cbbL, cbbM, accA and aclB genes in the rhizosphere soil (RS) and bulk soil (BS) were quantified. The application of P significantly altered the soil properties and stimulated the abundances of Bacteria, Archaea and CO2-fixation genes under CF treatment, but negatively influenced the abundances of Bacteria and marker genes of CO2-fixing autotrophs in BS soils under AWD treatment. The response of CO2-fixing autotrophs to P fertiliser depended on the irrigation management method. The redundancy analysis revealed that 54% of the variation in the functional marker gene abundances could be explained by the irrigation method, P fertiliser and the Olsen-P content; however, the rhizosphere effect did not have any significant influence. P fertiliser application under CF was more beneficial in improving the abundance of CO2-fixing autotrophs compared to the AWD treatment; thus, it is an ideal irrigation management method to increase soil carbon fixation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Increasing water productivity, nitrogen economy, and grain yield of rice by water saving irrigation and fertilizer-N management.

    Science.gov (United States)

    Aziz, Omar; Hussain, Saddam; Rizwan, Muhammad; Riaz, Muhammad; Bashir, Saqib; Lin, Lirong; Mehmood, Sajid; Imran, Muhammad; Yaseen, Rizwan; Lu, Guoan

    2018-06-01

    The looming water resources worldwide necessitate the development of water-saving technologies in rice production. An open greenhouse experiment was conducted on rice during the summer season of 2016 at Huazhong Agricultural University, Wuhan, China, in order to study the influence of irrigation methods and nitrogen (N) inputs on water productivity, N economy, and grain yield of rice. Two irrigation methods, viz. conventional irrigation (CI) and "thin-shallow-moist-dry" irrigation (TSMDI), and three levels of nitrogen, viz. 0 kg N ha -1 (N 0 ), 90 kg N ha -1 (N 1 ), and 180 kg N ha -1 (N 2 ), were examined with three replications. Study data indicated that no significant water by nitrogen interaction on grain yield, biomass, water productivity, N uptake, NUE, and fertilizer N balance was observed. Results revealed that TSMDI method showed significantly higher water productivity and irrigation water applications were reduced by 17.49% in TSMDI compared to CI. Thus, TSMDI enhanced root growth and offered significantly greater water saving along with getting more grain yield compared to CI. Nitrogen tracer ( 15 N) technique accurately assessed the absorption and distribution of added N in the soil crop environment and divulge higher nitrogen use efficiency (NUE) influenced by TSMDI. At the same N inputs, the TSMDI was the optimal method to minimize nitrogen leaching loss by decreasing water leakage about 18.63%, which are beneficial for the ecological environment.

  3. Study of soil bacterial and crop quality irrigated with treated municipal wastewater

    DEFF Research Database (Denmark)

    Alinezhadian, A; Karim, A; Mohammadi, J

    2014-01-01

    Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil...... bacterial and crops quality irrigated with treated wastewater. Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1...

  4. Optimisation of irrigation regime for early potatoes, late cauliflower, early cabbage and celery

    International Nuclear Information System (INIS)

    Zavadil, J.

    2006-01-01

    The paper deals with optimisation of threshold suction pressure of soil water on light soils for early potatoes, early cabbage, late cauliflower and celery on the basis of results from small-plot field experiments with differentiated irrigation regimes. Threshold suction pressures of soil water were identical for all crops: 15 kPa in treatment I, 30 kPa in treatment II, 60 kPa in treatment III, and 120 kPa in treatment IV. Precipitation, air temperature and relative humidity, global solar radiation, wind speed and direction were measured by an automated meteorological station. Reference and actual evapotranspirations were determined for the experimental crops according to FAO Paper No. 56 and by means of a biological curve (BC) in 2003-2005. To compare these two methods of calculation of actual evapotranspiration the soil moisture balance was found out. The optimum threshold suction pressure was 30 kPa for early potatoes, late cauliflower and cabbage and 15 kPa for celery. The seasonal irrigation depths determined on the basis of soil moisture balance, in which the crop evapotranspiration (ETc) was calculated either according to FAO 56 or by the BC, were substantially different from the really achieved irrigation depths with optimal suction pressure. The really achieved values were near to the depths calculated by the BC for potatoes, while for cauliflower, cabbage and celery they were similar to the depths calculated by the FAO 56 methodology. The theoretical irrigation depths calculated by the BC method sometimes differed substantially from those based on FAO 56. These differences were maximal for cauliflower and celery and minimal for cabbage. They decreased with decreasing irrigation depths. (author)

  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. 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.

  7. 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 ...

  8. 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

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. Location of irrigated land classified from satellite imagery - High Plains Area, nominal date 1992

    Science.gov (United States)

    Qi, Sharon L.; Konduris, Alexandria; Litke, David W.; Dupree, Jean

    2002-01-01

    Satellite imagery from the Landsat Thematic Mapper (nominal date 1992) was used to classify and map the location of irrigated land overlying the High Plains aquifer. The High Plains aquifer underlies 174,000 square miles in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The U.S. Geological Survey is conducting a water-quality study of the High Plains aquifer as part of the National Water-Quality Assessment Program. To help interpret data and select sites for the study, it is helpful to know the location of irrigated land within the study area. To date, the only information available for the entire area is 20 years old. To update the data on irrigated land, 40 summer and 40 spring images (nominal date 1992) were acquired from the National Land Cover Data set and processed using a band-ratio method (Landsat Thematic Mapper band 4 divided by band 3) to enhance the vegetation signatures. The study area was divided into nine subregions with similar environmental characteristics, and a band-ratio threshold was selected from imagery in each subregion that differentiated the cutoff between irrigated and nonirrigated land. The classified images for each subregion were mosaicked to produce an irrigated-land map for the study area. The total amount of irrigated land classified from the 1992 imagery was 13.1 million acres, or about 12 percent of the total land in the High Plains. This estimate is approximately 1.5 percent greater than the amount of irrigated land reported in the 1992 Census of Agriculture (12.8 millions acres).

  14. 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-...

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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...

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. Comparing water options for irrigation farmers using Modern Portfolio Theory

    NARCIS (Netherlands)

    Gaydon, D.S.; Meinke, H.B.; Rodriguez, D.; McGrath, D.J.

    2012-01-01

    For irrigation farmers, the deregulation of water markets and consequent emergence of water as a tradeable commodity calls for a method of comparing traditional on-farm water options (growing crops) with off-farm market options (selling water seasonally, or selling water licences permanently). The

  5. 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)

  6. 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...

  7. Microbial risk in wastewater irrigated lettuce: comparing Escherichia coli contamination from an experimental site with a laboratory approach.

    Science.gov (United States)

    Makkaew, P; Miller, M; Fallowfield, H J; Cromar, N J

    This study assessed the contamination of Escherichia coli, in lettuce grown with treated domestic wastewater in four different irrigation configurations: open spray, spray under plastic sheet cover, open drip and drip under plastic sheet cover. Samples of lettuce from each irrigation configuration and irrigating wastewater were collected during the growing season. No E. coli was detected in lettuce from drip irrigated beds. All lettuce samples from spray beds were positive for E. coli, however, no statistical difference (p > 0.05) was detected between lettuces grown in open spray or covered spray beds. The results from the field experiment were also compared to a laboratory experiment which used submersion of lettuce in wastewater of known E. coli concentration as a surrogate method to assess contamination following irrigation. The microbial quality of spray bed lettuces was not significantly different from submersed lettuce when irrigated with wastewater containing 1,299.7 E. coli MPN/100 mL (p > 0.05). This study is significant since it is the first to validate that the microbial contamination of lettuce irrigated with wastewater in the field is comparable with a laboratory technique frequently applied in the quantitative microbial risk assessment of the consumption of wastewater irrigated salad crops.

  8. Comparison of the removal of calcium hydroxide medicaments on the root canal treatment irrigated with manual and sonic agitation technique

    Directory of Open Access Journals (Sweden)

    Anna Muryani

    2017-11-01

    Full Text Available Introduction: Irrigation of the root canal system is an important part of the endodontic treatment principle which aims to improve the hygiene of the root canal system from any debris and medicament residue with the hydrodynamic system. Root irrigation technique can be done with the manual and sonic system by using 2.5% NaOCI irrigation solution. Calcium hydroxide is used as a medicament for root canal sterilization. Root canal treatment will fail due to the imperfect removal of calcium hydroxide residue. The objective of this research was to analyze the comparison of the removal of calcium hydroxide medicaments on the root canal treatment irrigated with manual and sonic agitation technique using 2.5% sodium hypochlorite solution. Methods: The methods used in this study was experimental laboratory. The sample used was 30 maxillary incisors. The teeth were then divided into two groups randomly, then the root canal preparation was done by the crown down technique with manual irrigation using 2.5% NaOCI solution. The radicular part of the teeth was then split longitudinally, given a standardized groove in the one-third of the apical part, then applied with water-solved calcium hydroxide. The teeth were unified afterwards by using flowable composites, then soaked in the artificial saliva at the temperature of 37ºC. The sample of the 1st group was irrigated by manual agitation technique, and the sample of the 2nd group 2 was irrigated by sonic agitation technique, then both were viewed by stereo microscope. The data results were analyzed by Kruskal-Wallis and Mann-Whitney tests. Results: The results of calcium hydroxide removal were different between the root canals that were irrigated using 2.5% sodium hypochlorite irrigation solution by manual agitation technique compared to the sonic agitation technique. Irrigation using 2.5% sodium hypochlorite irrigation solution with the sonic agitation techniques were proven to be more effective in lifting Ca

  9. Optimization strategies for improving irrigation water management of lower jhelum canal

    International Nuclear Information System (INIS)

    Rashid, M.U.

    2015-01-01

    The paper includes computing crop water requirement, identification of problems and optimization strategies for improved irrigation water management of a canal command. Lower Jhelum Canal (LJC) System was selected as a case study. Possible strategies for optimization are enhancing irrigation water productivity by high value and high yield crops, adoption of resource conservation interventions (RCIs) at the farm level, improving irrigation system efficiency and its management. Estimation of daily reference evapotranspiration of LJC command was carried out by Penman Montieth -2000 method and metrological data of Sargodha for the period 1999 to 2010 was used. Crop water requirements were computed from reference evapotranspiration, crop coefficients and periods of crops for existing cropping pattern. The comparison of the crop water requirements and available water supplies indicated shortage of more than 51% in Kharif and 54% in Rabi seasons. The gap between requirements and supplies is fulfilled by groundwater in the command. The structural measures identified in the present study for improving canal management include rationalization of canal capacities in keeping with the current water requirements and availability, rehabilitation and remodeling of canal network and lining of distributaries and minors in saline groundwater areas. An array of measures and practices identified for improved water management at the farm level include: improvement and lining of watercourses, proper farm design and layout, adoption of resource conservation technologies involving laser land leveling, zero tillage, and bed-furrow irrigation method. Adopting proper cropping systems considering land suitability and capacity building of farming community in improved soil, crop and water management technologies would enhance the water productivity in an effective and sustainable manner. (author)

  10. 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, ...

  11. 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.

  12. Clustering of Groundwater Used in Isfahan Landscape Irrigation and Their Qualititative Changes Over one Decade

    Directory of Open Access Journals (Sweden)

    Jahangir Abedi Koupai

    2010-06-01

    Full Text Available Ten irrigation wells were selected along Chaharbagh Street and the Zayandehrood River bank to investigate and classify the groundwaters used for irrigating Isfahan landscape for their quality. Monthly sampling was performed and the results of the quality tests were used as seasonal averages. Different measurements such as pH, EC, Na+, C1-, HCO3-, Fe+2 were made according to standard methods and the Surfer program was used and the results were represented as isolines. Also seasonal classification of wells was performed based on similarities found among the water quality of the wells using statistical programs. Results revealed the poor quality of water from some of the study wells due to the discharge of urban and industrial wastewaters, chemical manure, etc. Besides, investigation of changes in water quality indicated the declining irrigation water quality and the increasing availability of water for landscape irrigation.

  13. 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.

  14. Optimization of planting pattern plan in Logung irrigation area using linear program

    Science.gov (United States)

    Wardoyo, Wasis; Setyono

    2018-03-01

    Logung irrigation area is located in Kudus Regency, Central Java Province, Indonesia. Irrigation area with 2810 Ha of extent is getting water supply from Logung dam. Yet, the utilization of water at Logung dam is not optimal and the distribution of water is still not evenly distributed. Therefore, this study will discuss about the optimization of irrigation water utilization based on the beginning of plant season. This optimization begins with the analysis of hydrology, climatology and river discharge in order to determine the irrigation water needs. After determining irrigation water needs, six alternatives of planting patterns with the different early planting periods, i.e. 1st November, 2nd November, 3rd November, 1st December, 2nd December, and 3rd December with the planting pattern of rice-secondary crop-sugarcane is introduced. It is continued by the analysis of water distribution conducted using linear program assisted by POM-Quantity method for Windows 3 with the reliable discharge limit and the available land area. Output of this calculation are to determine the land area that can be planted based on the type of plant and growing season, and to obtaine the profits of harvest yields. Based on the optimum area of each plant species with 6 alternatives, the most optimum area was obtained at the early planting periods on 3rd December with the production profit of Rp 113.397.338.854,- with the planting pattern of rice / beans / sugarcane-rice / beans / sugarcane-beans / sugarcane.

  15. 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...

  16. 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 ...

  17. 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.

  18. 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...

  19. 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)

  20. The synthesis method for design of electron flow sources

    Science.gov (United States)

    Alexahin, Yu I.; Molodozhenzev, A. Yu

    1997-01-01

    The synthesis method to design a relativistic magnetically - focused beam source is described in this paper. It allows to find a shape of electrodes necessary to produce laminar space charge flows. Electron guns with shielded cathodes designed with this method were analyzed using the EGUN code. The obtained results have shown the coincidence of the synthesis and analysis calculations [1]. This method of electron gun calculation may be applied for immersed electron flows - of interest for the EBIS electron gun design.

  1. 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.

  2. Estimating irrigation water demand in the Moroccan Drâa Valley using contingent valuation.

    Science.gov (United States)

    Storm, Hugo; Heckelei, Thomas; Heidecke, Claudia

    2011-10-01

    Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management, knowledge about farmers' demand for irrigation water is crucial to assess reactions to water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this information often have prohibitive data requirements. In this paper, the Contingent Valuation Method (CVM) is adjusted to derive a demand function for irrigation water along farmers' willingness to pay for one additional unit of surface water or groundwater. An application in the Middle Drâa Valley in Morocco shows that the method provides reasonable results in an environment with limited data availability. For analysing the censored survey data, the Least Absolute Deviation estimator was found to be a more suitable alternative to the Tobit model as errors are heteroscedastic and non-normally distributed. The adjusted CVM to derive demand functions is especially attractive for water scarce countries under limited data availability. Copyright © 2011 Elsevier Ltd. All rights reserved.

  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. Risk Factors for Perioperative Complications in Endoscopic Surgery with Irrigation

    Directory of Open Access Journals (Sweden)

    João Manoel Silva, Jr.

    2013-07-01

    Full Text Available Background and objectives: Currently, endoscopic medicine is being increasingly used, albeit not without risks. Therefore, this study evaluated the factors associated with perioperative complications in endoscopic surgery with intraoperative irrigation. Method: A cohort study of six months duration. Patients aged ≥ 18 years undergoing endoscopic surgery with the use of irrigation fluids during the intraoperative period were included. Exclusion criteria were: use of diuretics, kidney failure, cognitive impairment, hyponatremia prior to surgery, pregnancy, and critically ill. The patients who presented with or without complications during the perioperative period were allocated into two groups. Complications evaluated were related to neurological, cardiovascular and renal changes, and perioperative bleeding. Results: In total, 181 patients were enrolled and 39 excluded; therefore, 142 patients met the study criteria. Patients with complications amounted to 21.8%, with higher prevalence in endoscopic prostate surgery, followed by hysteroscopy, bladder, knee, and shoulder arthroscopy (58.1%, 36.9%, 19.4%, 3.8%, 3.2% respectively. When comparing both groups, we found association with complications in univariate analysis: age, sex, smoking, heart disease, ASA, serum sodium at the end of surgery, total irrigation fluid administered, TURP, and hysteroscopy. However, in multiple regression analysis for complications, only age (OR = 1.048, serum sodium (OR = 0.962, and volume of irrigation fluid administered during surgery (OR = 1.001 were independent variables. Keywords: Anesthesia, Endoscopy, Hyponatremia, Postoperative Complications, Risk Assessment, Risk Factors.

  5. Choice of root canal irrigants by Serbian dental practitioners

    Directory of Open Access Journals (Sweden)

    Tošić Goran

    2016-01-01

    Full Text Available Background/Aim. Root canal treatment is considered to be the one of the most important procedures in endodontic treatment. To irrigate the root canal it is most common to use sodium hypochlorite (NaOCl, chlorhexodine, ethylenediami-netetraacetic acid (EDTA, local anesthetic solution, while the most used in Serbia is hydrogen peroxide (H2O2. The aim of this survey was to reveal the preferred root canal irrigants used by general dental practitioners in Serbia and to determine the influence of the continuing education program, delivered over the 3-year observation period, on work habits of dental practitioners. This was the first comprehensive survey of this nature carried out in Serbia. Methods. The survey was conducted in two instances, a 4-month observation period each, from November 1, 2009 to March 1, 2010 and from November 1, 2012 to March 1, 2013. Internet Web Page Survey was posted on the official web site of the Serbian Association of Private Dentists. In the first survey, 569 completed questionnaires were subjected to analysis. In the next attempt (3 years later, the survey was launched again and 615 completed questionnaires were analyzed using the same criteria. The statistical analysis was carried out with simple descriptive statistics applying the χ2 test, at a significance level of p < 0.05. Results. The first survey included 569 dental practitioners, while 3 years later the number of them was 615. Analyzing the questionnaires revealed the number of 10 to 30 interventins on the root canal montly. The most commonly used irrigant solution was H2O2 in 2009, while in 2012 it was yet H2O2, but also NaOCl, chlorhexodine, and a little less EDTA. Conclusion. This study shows significant changes in the irrigation protocol applied in Serbian dental community. After 3 years of observation, NaOCl became widely accepted as the irrigant of choice, whereas H2O2 lost its popularity.

  6. Declining Groundwater Levels in North India: Understanding Sources of Irrigation Inefficiency

    Science.gov (United States)

    O'Keeffe, J.; Buytaert, W.; Mijic, A.; Brozovic, N.

    2014-12-01

    Over the last half century, the green revolution has transformed India from a famine-prone, drought-susceptible country, into the world's third largest grain producer and one of the most intensely irrigated regions on the planet. This is in no small part due to the country's vast water resources along with an increase in tubewells and more advanced abstraction methods. While agricultural intensification has had undeniable benefits, it has, and continues to have a significant impact on water resources. Unless solutions which take into consideration the ever evolving socio-economic, hydrological and climatic conditions are found, India's agricultural future looks bleak.This research examines the irrigation behaviour of farmers, using data collected during field work in the State of Uttar Pradesh within the Ganges Basin of North India. Significant differences in farmer behaviour and irrigation practices are highlighted, not only between State districts but between individual farmers. This includes the volume of irrigation water applied and the price paid, as well as differences in the yields of crops produced. Analyses of results suggest that this is due to a number of factors, particularly the source of irrigation water. Study areas which had access to cheaper, but crucially less reliable, canal water were found to invest in more efficient water saving technologies in order to reduce the overall cost of irrigation during periods where less expensive canal water is not available. As a result, overall water use and irrigation cost is lower and yields are higher despite very similar climatic conditions. While cheap canal water is not an option for all farmers, the results show that the introduction of more efficient water saving technologies, despite the significant capital expenditure is a viable option for many farmers and costs can be recovered in a relatively short space of time. In addition, the reduction of declining water levels mean that water is abstracted from

  7. 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.

  8. Irrigated agriculture and future climate change effects on groundwater recharge, northern High Plains aquifer, USA

    Science.gov (United States)

    Lauffenburger, Zachary H.; Gurdak, Jason J.; Hobza, Christopher M.; Woodward, Duane; Wolf, Cassandra

    2018-01-01

    Understanding the controls of agriculture and climate change on recharge rates is critically important to develop appropriate sustainable management plans for groundwater resources and coupled irrigated agricultural systems. In this study, several physical (total potential (ψT) time series) and chemical tracer and dating (3H, Cl−, Br−, CFCs, SF6, and 3H/3He) methods were used to quantify diffuse recharge rates beneath two rangeland sites and irrigation recharge rates beneath two irrigated corn sites along an east-west (wet-dry) transect of the northern High Plains aquifer, Platte River Basin, central Nebraska. The field-based recharge estimates and historical climate were used to calibrate site-specific Hydrus-1D models, and irrigation requirements were estimated using the Crops Simulation Model (CROPSIM). Future model simulations were driven by an ensemble of 16 global climate models and two global warming scenarios to project a 2050 climate relative to the historical baseline 1990 climate, and simulate changes in precipitation, irrigation, evapotranspiration, and diffuse and irrigation recharge rates. Although results indicate statistical differences between the historical variables at the eastern and western sites and rangeland and irrigated sites, the low warming scenario (+1.0 °C) simulations indicate no statistical differences between 2050 and 1990. However, the high warming scenarios (+2.4 °C) indicate a 25% and 15% increase in median annual evapotranspiration and irrigation demand, and decreases in future diffuse recharge by 53% and 98% and irrigation recharge by 47% and 29% at the eastern and western sites, respectively. These results indicate an important threshold between the low and high warming scenarios that if exceeded could trigger a significant bidirectional shift in 2050 hydroclimatology and recharge gradients. The bidirectional shift is that future northern High Plains temperatures will resemble present central High Plains

  9. 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)

  10. The effects of different irrigation protocols on removing calcium ...

    African Journals Online (AJOL)

    Objective: The aim of this study was to evaluate the efficiencies of different irrigation protocols and solutions in the removal of calcium hydroxide (Ca[OH]2). Materials and Methods: Sixty-eight maxillary incisors were used. Root canals were prepared and filled with Ca(OH)2. Two control (n = 4) and six experimental groups (n ...

  11. 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

  12. 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 ...

  13. 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.

  14. Efficient electronic structure methods applied to metal nanoparticles

    DEFF Research Database (Denmark)

    Larsen, Ask Hjorth

    of efficient approaches to density functional theory and the application of these methods to metal nanoparticles. We describe the formalism and implementation of localized atom-centered basis sets within the projector augmented wave method. Basis sets allow for a dramatic increase in performance compared....... The basis set method is used to study the electronic effects for the contiguous range of clusters up to several hundred atoms. The s-electrons hybridize to form electronic shells consistent with the jellium model, leading to electronic magic numbers for clusters with full shells. Large electronic gaps...... and jumps in Fermi level near magic numbers can lead to alkali-like or halogen-like behaviour when main-group atoms adsorb onto gold clusters. A non-self-consistent NewnsAnderson model is used to more closely study the chemisorption of main-group atoms on magic-number Au clusters. The behaviour at magic...

  15. 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

  16. Water distribution in an orchard irrigated by perforated distributors in stony ground

    International Nuclear Information System (INIS)

    Decroix, M.; Marcesse, J.; Normand, M.

    1975-01-01

    In the context of new irrigation techniques the Compagnie Nationale d'Amenagement du Bas-Rhone et du Languedoc (B.Rh.L.) has developed a process of localized irrigation by perforated distributors. Conditions were defined for the optimum use of this process, especially the distribution of water in the ground. The study was carried out in a peach orchard in stony ground. The neutronic method was used to measure the soil moisture content. Because of the heterogeneous stone size distribution it was necessary for the specific humidity determination to take into account the dry apparent density. This parameter was measured by gammametry [fr

  17. 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...

  18. 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.

  19. 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.

  20. 14 CFR 1260.69 - Electronic funds transfer payment methods.

    Science.gov (United States)

    2010-01-01

    ... Government by electronic funds transfer through the Treasury Fedline Payment System (FEDLINE) or the... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS General Special Conditions § 1260.69 Electronic funds transfer payment methods...

  1. 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.

  2. 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.

  3. Variational methods in electron-atom scattering theory

    CERN Document Server

    Nesbet, Robert K

    1980-01-01

    The investigation of scattering phenomena is a major theme of modern physics. A scattered particle provides a dynamical probe of the target system. The practical problem of interest here is the scattering of a low­ energy electron by an N-electron atom. It has been difficult in this area of study to achieve theoretical results that are even qualitatively correct, yet quantitative accuracy is often needed as an adjunct to experiment. The present book describes a quantitative theoretical method, or class of methods, that has been applied effectively to this problem. Quantum mechanical theory relevant to the scattering of an electron by an N-electron atom, which may gain or lose energy in the process, is summarized in Chapter 1. The variational theory itself is presented in Chapter 2, both as currently used and in forms that may facilitate future applications. The theory of multichannel resonance and threshold effects, which provide a rich structure to observed electron-atom scattering data, is presented in Cha...

  4. System for cooling hybrid vehicle electronics, method for cooling hybrid vehicle electronics

    Science.gov (United States)

    France, David M.; Yu, Wenhua; Singh, Dileep; Zhao, Weihuan

    2017-11-21

    The invention provides a single radiator cooling system for use in hybrid electric vehicles, the system comprising a surface in thermal communication with electronics, and subcooled boiling fluid contacting the surface. The invention also provides a single radiator method for simultaneously cooling electronics and an internal combustion engine in a hybrid electric vehicle, the method comprising separating a coolant fluid into a first portion and a second portion; directing the first portion to the electronics and the second portion to the internal combustion engine for a time sufficient to maintain the temperature of the electronics at or below 175.degree. C.; combining the first and second portion to reestablish the coolant fluid; and treating the reestablished coolant fluid to the single radiator for a time sufficient to decrease the temperature of the reestablished coolant fluid to the temperature it had before separation.

  5. 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.

  6. Effects of Biochar on the Net Greenhouse Gas Emissions under Continuous Flooding and Water-Saving Irrigation Conditions in Paddy Soils

    Directory of Open Access Journals (Sweden)

    Le Qi

    2018-05-01

    Full Text Available In this study, we investigated the greenhouse gas emission under different application of biochar in the conditions of continuous flooding and water-saving irrigation in paddy fields, whereas, plant and soil carbon sequestration were considered in the calculation of net greenhouse gas emissions. The emission rates of methane (CH4, carbon dioxide (CO2, and nitrous oxide (N2O gases were simultaneously monitored once every 7–10 days using the closed-chamber method. As a whole, the net greenhouse gas emission in the water-saving irrigation was more than that of the continuous flooding irrigation conditions. Compared with the water-saving irrigation, the continuous flooding irrigation significantly increased the CH4 in the control (CK and chemical fertilizer treatments (NPK. The CO2 emissions increased in each treatment of the water-saving irrigation condition, especially in the chemical fertilizer treatments (NPKFW. Similarly, the soil N2O emission was very sensitive to the water-saving irrigation condition. An interesting finding is that the biochar application in soils cut down the soil N2O emission more significantly than NPKFW in the water-saving irrigation condition while the effect of biochar increased under the continuous flooding irrigation condition.

  7. 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.

  8. Mudflow utilization for construction materials of tertiary irrigation canal lining

    Science.gov (United States)

    Azis, Subandiyah; Kustamar

    2017-11-01

    Mudflow in Siring Village, Sidoarjo Regency, Indonesia, has been in eruption since May 29, 2006. It still shows irregular large bursts which loaded in a sludge reservoir with capacity of 59 million m3. From 2007 until 2015, there were more than 20 studies which concluded that the mudflow could be used as a mixture of building materials. However, the studies were not detailed and needed further research. This research aims to investigate the use of mudflow as tertiary irrigation canal lining material. This research comes with several laboratory tests to obtain a mixture that is solid and water-resistant. The methods that were used are descriptive methods as follows: 1). Sampling of mudflow, to be analyzed in Material Testing Laboratory. 2). Sampling of soil at research site, to be analyzed in Soil Mechanics Laboratory 3). Mixing of materials which are consist of mudflow and other materials and doing strength test in the laboratory. 4). Installation of tertiary irrigation canal lining using materials that have been tested. 5). Observation of lining's strength inactive soil pressure-bearing and its impermeability. It is expected that the results of this research will be applied extensively throughout the tertiary irrigation canals, so mudflow can be utilized as raw materials that are environmentally friendly, which are able to help preserving the environment, also to reduce the removal of sand / rock in the river, which has been used for lining materials, that benefits in preventing damage to the river ecosystem.

  9. Analysis and comparison of modern methods of turf irrigation, verifying the capability of existing information systems through the use of numerical modeling

    Science.gov (United States)

    Deangelis, Maria Laura; Facoetti, Nicola

    2016-04-01

    The automated irrigation of parks and gardens in public areas has become more and more a common practice due to the many benefits it brings in terms of improving the quality of urban green areas. Since this practice requires significant volumes of water, and this becomes increasingly scarce and expensive, it is necessary that the design criteria and use management aim at maximizing the irrigation efficiency. There are conflicting relationship and competition between trees and turf for several reasons. On one hand the different irrigation needs can cause excess water in the root zones of the trees, on the other hand the surface roots of trees and the shade created from the leaves by the dripline (projection line of the canopy) determine an unfavorable area to the growth of the turf because of light factor. It follows that for an optimal design of an irrigation system is necessary to separate the turf areas from trees, with the disadvantage of considerably complicate the geometries of the sprinklers. Each tree or group of trees need to be associated to a not irrigated area. This problem seems not to have a specifically bibliographical evidence, although there are operating standards primarily used to define buffer zones for trees from constructions (British Standard 5837:2005). Ideally, a high number of sprinklers is required to follow the shape of the areas perfectly. Hence, an additional step is necessary to simplify these geometries, identifying a correct scheme for the sprinkler spacing. Such a sequence of geometric operations has been tested on the "Indro Montanelli" park in Milan, obtaining a reduction of the irrigated area of 47% and a water saving of around 30%. We intend to continue the research applying the model to other parks, verifying its applicability in different situations.

  10. 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

  11. Optimization of Water Allocation between Different Crops in Water Stress Conditions in Qazvin Irrigation Network

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammad khani

    2017-06-01

    Full Text Available Introduction: Evaluations show the necessity of using optimization models in order to determine optimal allocation of water in different water conditions. Its use can be proposed according to developed model abilities in this study in order to optimize water productivity and provide sustainable management and development of water resources over irrigation and drainage networks. Basic needs of the earth growing population and limitation of water and soil resources remindnecessity of optimal use of resources. World’s more than 280 million hectare lands are covered by irrigation networks (Khalkhali et al., 2006. The efficiency of most projects is between 30-50 percent and studies show that performance of most irrigation and drainage networks is not desirable and they have not achieved their aims. Hirich et al. (2014 Used deficit irrigation to improve crop water productivity of sweet corn, chickpea, faba bean and quinoa. For all crops, the highest water productivity and yield were obtained when deficit irrigation was applied during the vegetative growth stage. During the second season 2011 two cultivars of quinoa, faba bean and sweet corn have been cultivated applying 6 deficit irrigation treatments (rainfed, 0, 25, 50, 75 and 100% of full irrigation only during the vegetative growth stage, while in the rest of a crop cycle full irrigation was provided except for rainfed treatment. For quinoa and faba bean, treatment receiving 50% of the full irrigation during the vegetative growth stage recorded the highest yield and water productivity, while for sweet corn applying 75% of full irrigation was the optimal treatment in terms of yield and water productivity. Moghaddasi et al. (2010 worked examines and compares this approach with that based on the optimization method to manage agricultural water demand during drought to minimize damage. The results show that the optimization method resulted in 42% more income for the agricultural sector using the

  12. Sugar cane yield response to deficit irrigation at two growth stages

    International Nuclear Information System (INIS)

    Pene, C.B.G.

    1995-01-01

    A field study on sugar cane (Saccharum officinarum L.) yield response to deficit irrigation during both tillering and stem elongation stages, in order to increase crop water use efficiency, was carried out at Institut des Savanes (IDESSA) experimental station of Ferkessedougou, in Northern Ivory Coast. This cane crop tested was Co 449, an early - maturing genotype of indian origin. This experiment has been conducted for three consecutive years as virgin crop ( from November, 1991 to December 1992 ), first ratoon crop ( from December 1992 to January 1994 ) and as second ratoon crop ( from January 1994 to January 1995 ). The experimental design was a randomized complete block with 10 irrigation treatments in 4 replicates of 54 m sup2 sized plots. Water was applied through an improved furrow irrigation system. Crop water consumption was estimated using the water balance approach based on neutron probe and tensiometer measurements. This field water balance method required the determination of soil hydraulic conductivity as a function of water content and the neutron calibration curve. Data presented are related to the two ratoon crops for which field water balance measurements were investigated. It has been shown in the study that sugar cane growth and yield decline due to water deficit is significantly high during stem elongation as compared to tillering. As a result, the sugar cane tested was much more sensitive to water stress at stem elongation than at tillering. Therefore, deficit irrigation practice as to increase crop water use efficiency might be recommended at tillering rather than stem elongation. The water management strategy to be suggested here may consist of omitting irrigation during tillering ( assuming that the crop is successfully established ), for the benefit of stem elongation. As far as stem elongation is concerned, a moderate water deficit of about 25% with respect to the full irrigation regime appears to increase crop water use efficiency.6 figs

  13. The Immediate and Delayed Post-Debridement Effects on Tissue Bacterial Wound Counts of Hypochlorous Acid Versus Saline Irrigation in Chronic Wounds.

    Science.gov (United States)

    Hiebert, John M; Robson, Martin C

    2016-01-01

    Introduction: Wound debridement is considered essential in chronic wound management. Hypochlorous acid has been shown to be an effective agent in reducing wound bacterial counts in open wounds. Ultrasound-enabled wound debridement is an effective and efficient method of debridement. This study compared ultrasound irrigation with hypochlorous acid versus saline irrigation for wound debridement on pre- and postoperative wounds and determined regrowth of bacteria over 1 week period of time. Finally, the outcome of definitive wound closure of the clinically clean-appearing wounds was recorded. Methods: Seventeen consenting adult patients with chronic open wounds were randomly selected for study. The patients were randomly divided into the hypochlorous acid irrigation or saline irrigation group. All patients provided pre- and postoperative tissue samples for qualitative and quantitative bacteriology. For the time (7 days) between the debridement procedure and the definitive closure procedure, the wounds were dressed with a silver-impregnated dressing and a hydroconductive dressing. Results : Both types of irrigation in the ultrasonic system initially lowered the bacterial counts by 4 to 6 logs. However, by the time of definitive closure, the saline-irrigated wounds had bacterial counts back up to 10 5 whereas the hypochlorous acid-irrigated wounds remained at 10 2 or fewer. More than 80% of patients in the saline group had postoperative closure failure compared with 25% of patients in the hypochlorous acid group. Conclusions: Hypochlorous acid irrigation with ultrasound debridement reduced bacterial growth in chronic open wounds more efficiently than saline alone. Postoperative wound closure outcomes suggest a remarkable reduction in wound complications after wound debridement using hypochlorous acid irrigation with ultrasound versus saline alone.

  14. Demand Estimation for Irrigation Water in the Moroccan Drâa Valley using Contingent Valuation

    OpenAIRE

    Storm, Hugo; Heckelei, Thomas; Heidecke, Claudia

    2010-01-01

    Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management knowledge about farmers’ irrigation water demand is crucial to assess demand reactions of a water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this in...

  15. Mapping Soil hydrologic features in a semi-arid irrigated area in Spain

    Science.gov (United States)

    Jiménez-Aguirre, M.° Teresa; Isidoro, Daniel; Usón, Asunción

    2016-04-01

    The lack of soil information is a managerial problem in irrigated areas in Spain. The Violada Irrigation District (VID; 5234 ha) is a gypsic, semi-arid region in the Middle Ebro River Basin, northeast Spain. VID is under irrigation since the 1940's. The implementation of the flood irrigation system gave rise to waterlogging problems, solved along the years with the installation of an artificial drainage network. Aggregated water balances have been performed in VID since the early 1980's considering average soil properties and aggregated irrigation data for the calculations (crop evapotranspiration, canal seepage, and soil drainage). In 2008-2009, 91% of the VID was modernized to sprinkler irrigation. This new system provides detailed irrigation management information that together with detailed soil information would allow for disaggregated water balances for a better understanding of the system. Our goal was to draw a semi-detailed soil map of VID presenting the main soil characteristics related to irrigation management. A second step of the work was to set up pedotransfer functions (PTF) to estimate the water content and saturated hydraulic conductivity (Ks) from easily measurable parameters. Thirty four pits were opened, described and sampled for chemical and physical properties. Thirty three additional auger holes were sampled for water holding capacity (WHC; down to 60 cm), helping to draw the soil units boundaries. And 15 Ks tests (inverse auger hole method) were made. The WHC was determined as the difference between the field capacity (FC) and wilting point (WP) measured in samples dried at 40°C during 5 days. The comparison with old values dried at 105°C for 2 days highlighted the importance of the method when gypsum is present in order to avoid water removal from gypsum molecules. The soil map was drawn down to family level. Thirteen soil units were defined by the combination of five subgroups [Typic Calcixerept (A), Petrocalcic Calcixerept (B), Gypsic

  16. ANTIMICROBIAL AND STRUCTURAL EFFECTS OF DIFFERENT IRRIGATION SOLUTIONS ON GUTTA-PERCHA CONES

    Directory of Open Access Journals (Sweden)

    Sevinç Aktemur Türker

    2015-01-01

    Full Text Available Purpose: To evaluate the alterations on the surface of gutta-percha cones (GPCs on exposure to the different irrigation solutions and their possible antibacterial effect against Enterococcus faecalis. (E. faecalis Materials and Methods: Disinfection ability of different solutions (5.25% sodium hypochlorite, 2% chlorhexidine, 1% peracetic acid, and QMix were tested with 96 GPCs and the time of exposure to each solution was 5 and10 minutes, respectively. GPCs used in this study were contaminated with E.faecalis. After disinfection, GPCs were placed in tubes containing the medium and incubated at 37˚C for 7 days. All tubes were visually checked for turbidity at 24-hour intervals. About 92 new GPCs were analyzed by means of SEM/EDS to assess the topography and chemical elements present on their surface. The data generated was analyzed using Pearson chi-square test, p0.05. SEM/EDS analyses showed no alteration in the superficial features of GPCs after treating with various irrigation solutions. Conclusion: QMix was found to be an effective agent for rapid disinfection of GPCs as well-known irrigation solutions. Irrigation solutions were found to have sterilized the GPCs after both 5 and 10 minutes of exposure.

  17. Influence of Microsprinkler Irrigation Amount on Water, Soil, and pH Profiles in a Coastal Saline Soil

    Directory of Open Access Journals (Sweden)

    Linlin Chu

    2014-01-01

    Full Text Available Microsprinkler irrigation is a potential method to alleviate soil salinization. After conducting a homogeneous, highly saline, clayey, and coastal soil from the Bohai Gulf in northern China in a column experiment, the results show that the depth of the wetting front increased as the water amount applied increased, low-salinity and low-SAR enlarged after irrigation and water redistribution, and the soil pH increased with an increase in irrigation amount. We concluded that a water amount of 207 mm could be used to reclaim the coastal saline soil in northern China.

  18. 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 ...

  19. 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...

  20. Water-yield relationships of potato under different irrigation methods and regimens Relação água-produção na cultura da batata sob diferentes métodos e regimes de irrigação

    Directory of Open Access Journals (Sweden)

    Tolga Erdem

    2006-06-01

    Full Text Available Yield response to irrigation of different crops is of major importance in production planning where water resources are limited. This study aims to determine the effect of different irrigation methods and irrigation regimens on potato yield in the Trakya Region, Turkey, during 2003 and 2005. Potato was grown under furrow and drip irrigation methods and three regimens: irrigation applied when 30, 50, or 70% of the available water was consumed. The seasonal potato evapotranspiration ranged on 501 to 683 mm in 2003, and 464 to 647 mm in 2005. The furrow and drip irrigation methods had no significant effect on tuber yield for both years. Irrigation regimens influenced tuber yield (P Em casos de limitações de recursos hídricos, o planejamento da produção agrícola depende da resposta dos parâmetros de produção à prática da irrigação. Este estudo visa determinar o efeito de diferentes métodos e regimes de irrigação na produtividade da batata na região de Trakya, Turquia, durante os anos de 2003 e 2005. As batatas foram plantadas sob irrigação por sulcos e por gotejamento, em três regimes: prática de irrigação quando 30, 50 ou 70% da água disponível era consumida. A evapotranpisração sazonal da cultura variou entre 501 e 683 mm em 2003, e entre 464 e 647 mm em 2005. O método de irrigação não afetou significativamente a produção de tubérculos nos dois anos. Os regimes de irrigação influenciaram a produção de tubérculos (P < 0,05 em 2005, e as maiores produções foram registradas para o regime de irrigação 30%, 33,15 t ha-1 em 2003 e 44.56 t ha-1 em 2005. Os valores de eficiência do uso da água aumentaram de 4,70 para 6,63 nos tratamentos de irrigação por sulcos e de 5,19 para 9,47 kg m-3 nos tratamentos por gotejamento.

  1. 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

  2. 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.

  3. Factors Affecting the Ability of Agriculture to Pay Irrigation-Water Costs

    Energy Technology Data Exchange (ETDEWEB)

    Hagood, M. A. [Land and Water Development Division, Food and Agriculture Organization of the United Nations, Rome (Italy)

    1967-11-15

    There are no universally acceptable standard criteria for determining how much agriculture can pay for irrigation water. Justification of cost will depend upon the country's need to develop its soil and water resources for food, for international trade, and for its cumulative effect on other industries in comparison with other possible uses and their over-all contributions to the economy. Social and political conditions often have as much or more influence on development cost decisions than do strictly economic analyses. Many studies indicate that US $0.10/1000 US gal is an upper limit of acceptable costs for developing irrigation water at present economic levels. Under private development and on projects where water users must pay total water costs, methods are available for making feasibility budgets based on present prices. Because of inflation, world food shortage, recessions, future population and other unknown factors, it is hazardous to predict how much farmers or agriculture can pay for irrigation water. Better utilization of water available now offers opportunities for ''developing'' sources at costs much less than those for sources such as sea-water conversion. (author)

  4. Effect of organic matter, irrigation and soil mulching on the nutritional ...

    African Journals Online (AJOL)

    Rukevwe S. Abraka

    2016-11-30

    Nov 30, 2016 ... necessary for the soil humidity to be in an adequate amount (Danso ... clay, with soil and particle density of: 1.51 and 2.76 g cm-3, respectively ..... fertilization and irrigation methods on nitrogen uptake, intercepted ŷ = 2373.4 + ...

  5. Comparative evaluation of two subgingival irrigating solutions in the management of periodontal disease: A clinicomicrobial study

    Directory of Open Access Journals (Sweden)

    Dhara Jayesh Pandya

    2016-01-01

    Full Text Available Context: Local administration of antimicrobial agents offer a “site-specific” approach to the periodontal therapy and it has several benefits. Aim: The present study was aimed to assess the clinical and microbial changes by subgingival irrigation using different subgingival irrigants in periodontitis patients and also to assess the mechanical effect of different local irrigation devices; if any. Settings and Design: Split-mouth design was employed on ten individuals. Materials and Methods: The study sample consisted of 10 individuals in whom full-mouth scaling and root planing was performed and subgingival irrigation therapy was instituted for an experimental period of 30 days. The clinical as well as microbiological parameters were evaluated. Statistical Analysis Used: To calculate baseline data with day thirty data,paired t-test was used. Intergroup comparison was carried out using one-way ANOVA. Multiple comparisons among groups were carried out using post hoc Tamhane's T2 test. Results: Among the different subgingival irrigants used, 0.2% chlorhexidine gluconate is most effective followed by ozonated water, whereas saline was found to be ineffective when compared to the other two subgingival irrigants. Subgingival irrigation using pulsated device may not have any additive effect in alteration of the subgingival microflora. Conclusion: Within the limits and scope of the study, it can be safely concluded that 0.2% chlorhexidine may be used as an adjunct to mechanical therapy for achieving a significant reduction in inflammatory periodontal changes and also reduction in periodontopathogenic microflora.

  6. Enhancing the Productivity of High Value Crops and Income Generation with Small-Scale Irrigation Technologies in Kenya. Final Report 2009-2013

    International Nuclear Information System (INIS)

    2014-02-01

    The project was implemented by the Kenya Agricultural Research Institute in collaboration with key irrigation stakeholders including Horticultural Crops Development Authority (HCDA), G North and Son limited, Kenya Irrigation and Drainage Association (KIDA), Jomo Kenyatta University of Agriculture and Technology (JKUAT), Greenbelt Movement and Ministry of Agriculture. The objective was to develop and pilot test appropriate irrigation systems (methods and related water/nutrient management practices) for small-scale farmers for increasing yield, quality of high value crops and farmers income to improved livelihood. The project built on earlier work on low head drip irrigation in Kenya involving KARI led promotion among the peri-urban and rural communities. The Equipment used include Neutron Probe Hydroprobe, Ammonium Sulphate Fertilizers (5% a.e), drip irrigation kits, MoneyMaker irrigation pumps, Pessl imetos weather station, SDEC tensimetre and tensiometers), Venturi injectors, among others.

  7. Electron microscopy methods in studies of cultural heritage sites

    Science.gov (United States)

    Vasiliev, A. L.; Kovalchuk, M. V.; Yatsishina, E. B.

    2016-11-01

    The history of the development and application of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray microanalysis (EDXMA) in studies of cultural heritage sites is considered. In fact, investigations based on these methods began when electron microscopes became a commercial product. Currently, these methods, being developed and improved, help solve many historical enigmas. To date, electron microscopy combined with microanalysis makes it possible to investigate any object, from parchment and wooden articles to pigments, tools, and objects of art. Studies by these methods have revealed that some articles were made by ancient masters using ancient "nanotechnologies"; hence, their comprehensive analysis calls for the latest achievements in the corresponding instrumental methods and sample preparation techniques.

  8. 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)

  9. 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 ...

  10. 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

  11. 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 ...

  12. Evaluation of greenhouse gas emissions in relation to irrigation methods and sustainable production in California orchard

    Science.gov (United States)

    California (CA) is one of the top agricultural production states in the United States of America (USA). Increasing water use efficiency and minimizing environmental impact are two of the major elements affecting sustainability of irrigated agriculture in CA. Field research has been conducted to eval...

  13. 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

  14. 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

  15. 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.

  16. 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...

  17. Effect of Er:YAG laser-activated irrigation solution on Enterococcus Faecalis biofilm in an ex-vivo root canal model.

    Science.gov (United States)

    Sahar-Helft, Sharonit; Stabholtz, Adam; Moshonov, Joshua; Gutkin, Vitaly; Redenski, Idan; Steinberg, Doron

    2013-07-01

    Abstract Objective: The purpose of this study was to evaluate mineral content and surface morphology of root canals coated with Enterococcus faecalis biofilm after treatment with several endodontic irrigation solutions, with and without Er:YAG laser-activated irrigation (LAI). LAI has been introduced as a powerful method for root canal irrigation resulting in smear-layer removal from the root canal wall. Distal and palatal roots from 60 freshly extracted human molars were used in this study. The coronal of each tooth was removed. Roots were split longitudinally and placed in an ultrasonic bath to remove the smear layer, creating conditions for the formation of E. faecalis biofilm. After incubation, the two halves were reassembled in impression material to simulate clinical conditions. Specimens were divided into two main groups: roots rinsed with irrigation solutions and roots subjected to laser irradiation combined with irrigation solutions. Solutions tested were 2% chlorhexidine and 17% ethylenediaminetetraacetic acid (EDTA) and saline. Surface morphology: 17% EDTA irrigant solution combined with Er:YAG laser showed the best results for removing bacteria from the root canal walls. Chemical analysis: all samples treated with combined laser irradiation and irrigation solution had low surface levels of Ca compared with samples treated with irrigation alone. The Ca/P ratio was highest in the laser-EDTA group. Overall, mineral changes caused by laser with irrigation solutions were minimal, and statistically nonsignificant. In vitro irrigation solutions, combined with Er:YAG laser irradiation, were effective in removing E. faecalis biofilm from root canal walls. Irrigation solutions without laser irradiation were less effective, leaving a layer of biofilm on the dentin surface.

  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. The key role of supply chain actors in groundwater irrigation development in North Africa

    Science.gov (United States)

    Lejars, Caroline; Daoudi, Ali; Amichi, Hichem

    2017-09-01

    The role played by supply chain actors in the rapid development of groundwater-based irrigated agriculture is analyzed. Agricultural groundwater use has increased tremendously in the past 50 years, leading to the decline of water tables. Groundwater use has enabled intensification of existing farming systems and ensured economic growth. This "groundwater economy" has been growing rapidly due to the initiative of farmers and the involvement of a wide range of supply chain actors, including suppliers of equipment, inputs retailers, and distributors of irrigated agricultural products. In North Africa, the actors in irrigated production chains often operate at the margin of public policies and are usually described as "informal", "unstructured", and as participating in "groundwater anarchy". This paper underlines the crucial role of supply chain actors in the development of groundwater irrigation, a role largely ignored by public policies and rarely studied. The analysis is based on three case studies in Morocco, Tunisia and Algeria, and focuses on the horticultural sub-sector, in particular on onions and tomatoes, which are irrigated high value crops. The study demonstrates that although supply chain actors are catalyzers of the expansion of groundwater irrigation, they could also become actors in adaptation to the declining water tables. Through their informal activities, they help reduce market risks, facilitate credit and access to subsidies, and disseminate innovation. The interest associated with making these actors visible to agricultural institutions is discussed, along with methods of getting them involved in the management of the resource on which they depend.

  3. Multi-Stream Saline-Jet Dissection Using a Simple Irrigation System Defines Difficult Tissue Planes

    Science.gov (United States)

    Ng, Philip CH

    2010-01-01

    Introduction: Single-stream hydro-jet dissection is increasingly used in various laparoscopic procedures, but its use requires special equipment. We describe a simple method for using an irrigation system for saline-jet tissue dissection as a useful adjunct prior to adhesiolysis. Material and Methods: Intraabdominal adhesions prolong laparoscopic procedures, because tissue planes are difficult to identify. We performed multi-jet saline dissection (MSSJ) between 2000 and 2009 in more than 500 patients during laparoscopy involving hernias, gallbladders, appendices, and intestinal obstructions. We use a standard suction irrigation probe, which is attached to a 1-liter saline bag with an inflatable cuff around to create a pressure of 250mm Hg to 300mm Hg. In effect, this is the standard setup generally used for irrigation. After using saline dissection, tissue planes can be better defined and the structures can then be separated. Result and Discussion: Using this method, we have successfully identified tissue planes in spite of dense adhesions, and our conversion rates to open have been reduced dramatically. This method is relatively safer than other modalities of tissue dissection, such as diathermy, ultrasonic, blunt or sharp dissection. The disadvantage is that with tissues saturated with saline it becomes more difficult to use diathermy hemostasis. Care has to be exercised in monitoring the temperature and volume of the fluid used. PMID:20529528

  4. Electron microscopy methods in studies of cultural heritage sites

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, A. L., E-mail: a.vasiliev56@gmail.com; Kovalchuk, M. V.; Yatsishina, E. B. [National Research Centre “Kurchatov Institute” (Russian Federation)

    2016-11-15

    The history of the development and application of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray microanalysis (EDXMA) in studies of cultural heritage sites is considered. In fact, investigations based on these methods began when electron microscopes became a commercial product. Currently, these methods, being developed and improved, help solve many historical enigmas. To date, electron microscopy combined with microanalysis makes it possible to investigate any object, from parchment and wooden articles to pigments, tools, and objects of art. Studies by these methods have revealed that some articles were made by ancient masters using ancient “nanotechnologies”; hence, their comprehensive analysis calls for the latest achievements in the corresponding instrumental methods and sample preparation techniques.

  5. Electron microscopy methods in studies of cultural heritage sites

    International Nuclear Information System (INIS)

    Vasiliev, A. L.; Kovalchuk, M. V.; Yatsishina, E. B.

    2016-01-01

    The history of the development and application of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray microanalysis (EDXMA) in studies of cultural heritage sites is considered. In fact, investigations based on these methods began when electron microscopes became a commercial product. Currently, these methods, being developed and improved, help solve many historical enigmas. To date, electron microscopy combined with microanalysis makes it possible to investigate any object, from parchment and wooden articles to pigments, tools, and objects of art. Studies by these methods have revealed that some articles were made by ancient masters using ancient “nanotechnologies”; hence, their comprehensive analysis calls for the latest achievements in the corresponding instrumental methods and sample preparation techniques.

  6. Computational methods of electron/photon transport

    International Nuclear Information System (INIS)

    Mack, J.M.

    1983-01-01

    A review of computational methods simulating the non-plasma transport of electrons and their attendant cascades is presented. Remarks are mainly restricted to linearized formalisms at electron energies above 1 keV. The effectiveness of various metods is discussed including moments, point-kernel, invariant imbedding, discrete-ordinates, and Monte Carlo. Future research directions and the potential impact on various aspects of science and engineering are indicated

  7. 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

  8. A GIS-based assessment of groundwater suitability for irrigation purposes in flat areas of the wet Pampa plain, Argentina.

    Science.gov (United States)

    Romanelli, Asunción; Lima, María Lourdes; Quiroz Londoño, Orlando Mauricio; Martínez, Daniel Emilio; Massone, Héctor Enrique

    2012-09-01

    The Pampa in Argentina is a large plain with a quite obvious dependence on agriculture, water availability and its quality. It is a sensitive environment due to weather changes and slope variations. Supplementary irrigation is a useful practice for compensating the production in the zone. However, potential negative impacts of this type of irrigation in salinization and sodification of soils are evident. Most conventional methodologies for assessing water irrigation quality have difficulties in their application in the region because they do not adjust to the defined assumptions for them. Consequently, a new GIS-based methodology integrating multiparametric data was proposed for evaluating and delineating groundwater suitability zones for irrigation purposes in flat areas. Hydrogeological surveys including water level measurements, groundwater samples for chemical analysis and electrical conductivity (EC) measurements were performed. The combination of EC, sodium adsorption ratio, residual sodium carbonate, slopes and hydraulic gradient parameters generated an irrigation water index (IWI). With the integration of the IWI 1 to 3 classes (categories of suitable waters for irrigation) and the aquifer thickness the restricted irrigation water index (RIWI) was obtained. The IWI's index application showed that 61.3 % of the area has "Very high" to "Moderate" potential for irrigation, while the 31.4 % of it has unsuitable waters. Approximately, 46 % of the tested area has high suitability for irrigation and moderate groundwater availability. This proposed methodology has advantages over traditional methods because it allows for better discrimination in homogeneous areas.

  9. 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.

  10. 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...

  11. Method of fabricating a cooled electronic system

    Science.gov (United States)

    Chainer, Timothy J; Gaynes, Michael A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Schultz, Mark D; Simco, Daniel P; Steinke, Mark E

    2014-02-11

    A method of fabricating a liquid-cooled electronic system is provided which includes an electronic assembly having an electronics card and a socket with a latch at one end. The latch facilitates securing of the card within the socket. The method includes providing a liquid-cooled cold rail at the one end of the socket, and a thermal spreader to couple the electronics card to the cold rail. The thermal spreader includes first and second thermal transfer plates coupled to first and second surfaces on opposite sides of the card, and thermally conductive extensions extending from end edges of the plates, which couple the respective transfer plates to the liquid-cooled cold rail. The extensions are disposed to the sides of the latch, and the card is securable within or removable from the socket using the latch without removing the cold rail or the thermal spreader.

  12. Effect of sequential surface irrigations on field-scale emissions of 1,3-dichloropropene.

    Science.gov (United States)

    Yates, S R; Knuteson, J; Ernst, F F; Zheng, W; Wang, Q

    2008-12-01

    A field experiment was conducted to measure subsurface movement and volatilization of 1,3-dichloropropene (1,3-D) after shank injection to an agricultural soil. The goal of this study was to evaluate the effect of sprinkler irrigation on the emissions of 1,3-D to the atmosphere and is based on recent research that has shown that saturating the soil pore space reduces gas-phase diffusion and leads to reduced volatilization rates. Aerodynamic, integrated horizontal flux, and theoretical profile shape methods were used to estimate fumigant volatilization rates and total emission losses. These methods provide estimates of the volatilization rate based on measurements of wind speed, temperature, and 1,3-D concentration in the atmosphere. The volatilization rate was measured continuously for 16 days, and the daily peak volatilization rates for the three methods ranged from 18 to 60 microg m(-2) s(-1). The total 13-D mass entering the atmosphere was approximately 44-68 kg ha(-1), or 10-15% of the applied active ingredient This represents approximately 30-50% reduction in the total emission losses compared to conventional fumigant applications in field and field-plot studies. Significant reduction in volatilization of 1,3-D was observed when five surface irrigations were applied to the field, one immediately after fumigation followed by daily irrigations.

  13. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  15. An electron moiré method for a common SEM

    Institute of Scientific and Technical Information of China (English)

    Y.M.Xing; S.Kishimoto; Y.R.Zhao

    2006-01-01

    In the electron moiré method,a high-frequency grating is used to measure microscopic deformation,which promises significant potential applications for the method in the microscopic analysis of materials.However,a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope (SEM).Because only a few SEMs used in the material science studies are equipped with this device,the use of the electron moiré method is limited.In this study,an electron moiré method for a common SEM without the beam control device is presented.A grating based on a multi-scanning concept is fabricated in any observing mode.A real-time moiré pattern can also be generated in the SEM or an optical filtering system.Without the beam control device being a prerequisite,the electron moiré method can be more widely used.The experimental results from three different types of SEMS show that high quality gratings with uniform lines and less pitch error can be fabricated by this method,and moiré patterns can also be correctly generated.

  16. Investigating the evolutionary history of irrigated agricultural technology in the Heihe River Basin, China

    Science.gov (United States)

    Wu, S.; Wei, Y.; Zhao, Y.; Zheng, H.

    2017-12-01

    Human's innovative abilities do not only enable rapid expansion of civilization, but also lead to enormous modifications on the natural environment. Technology, while a key factor embedded in socioeconomic developments, its impacts have been rarely appropriately considered in river basin management. This research aims to examine the evolutionary history of irrigated agricultural technology in the Heihe River Basin, China, and how its characteristics interacted with the river basin environment. It adopts a content analysis approach to collect and summarize quantitative technological information in the Heihe River Basin across a time span of more than 2000 years from the Han Dynasty (206 BC) to 2015. Two Chinese academic research databases: Wan Fang Data and China National Knowledge Infrastructure (CNKI) were chosen as data sources. The results show that irrigated agricultural technologies in Heihe River Basin have shifted from focusing on developing new farming tools and cultivation methods to adapting modernized, water-saving irrigation methods and water diversion infrastructures. In additions, the center of irrigated agricultural technology in the Heihe river basin has moved from downstream to middle stream since the Ming Dynasty (1368AD) as a result of degraded natural environment. The developing trend of technology in the Heihe River Basin thus coincides with the change of societal focus from agricultural production efficiency to the human-water balance and environmental remediation. This research demonstrates that irrigated agricultural technologies had a twisted evolutionary history in the Heihe River Basin, influenced by a diverse range of environmental and socioeconomic factors. It provides insights into the fact that technology exhibits a co-evolutionary characteristic with the social development history in the region, pointing towards the urgent need to maintain the balance between human and environment.

  17. [The results of self-irrigation in colostomy patients who have undergone a process of systematic training].

    Science.gov (United States)

    Santos, V L; Koizumi, M S

    1992-12-01

    The present study comprises the results of the use of self-irrigation by 40 colostomized patients, trained by us through a process of systematized training. The effectiveness of the training process can be checked out considering that the most part of the patients have adopted it in its basic features, pointing out a few number of technical difficulties. As to the results of self-irrigation, as a method for controlling the intestinal habit, we can say that 37.50% of the population showed an absence of fecal leakages and 42.50%, sporadic leakages between the irrigations; 27.50% and 35.00%, with absence of gases in the intervals of time and partial use of the collecting pouch, respectively.

  18. 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.

  19. 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.

  20. Luminescence dating of flash flood deposits: a new approach for the chronological study of ancient irrigation perimeters in southern Yemen

    International Nuclear Information System (INIS)

    Balescu, S.; Lamothe, M.; Coque-Delhuille, B.

    1998-01-01

    This study is an attempt to assess the age of ancient irrigation silts from Southern Yemen using the optically stimulated luminescence (OSL) of the constituent K-feldspar grains. This OSL dating method is tested on the al-Haraja irrigation sequence (Wadi Bayhan) which overlies an archaeological occupation level previously dated at 2 203±123 years BP by 14 C. The OSL age estimates range between 2 097±177 years at the bottom of the sequence and 1 555±150 years at the top. This study demonstrates the potential of the luminescence dating method to provide chronological information on the deposition of ancient silts following irrigation in arid environment where 14 C datable material is rare. (authors)