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 )

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 ...

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.

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...

Effects of different irrigation practices using treated wastewater on tomato yields, quality, water productivity, and soil and fruit mineral contents.

Science.gov (United States)

Demir, Azize Dogan; Sahin, Ustun

2017-11-01

Wastewater use in agricultural irrigation is becoming a common practice in order to meet the rising water demands in arid and semi-arid regions. The study was conducted to determine the effects of the full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation practices using treated municipal wastewater (TWW) and freshwater (FW) on tomato yield, water use, fruit quality, and soil and fruit heavy metal concentrations. The TWW significantly increased marketable yield compared to the FW, as well as decreased water consumption. Therefore, water use efficiency (WUE) in the TWW was significantly higher than in the FW. Although the DI and the PRD practices caused less yields, these practices significantly increased WUE values due to less irrigation water applied. The water-yield linear relationships were statistically significant. TWW significantly increased titratable acidity and vitamin C contents. Reduced irrigation provided significantly lower titratable acidity, vitamin C, and lycopene contents. TWW increased the surface soil and fruit mineral contents in response to FW. Greater increases were observed under FI, and mineral contents declined with reduction in irrigation water. Heavy metal accumulation in soils was within safe limits. However, Cd and Pb contents in fruits exceeded standard limits given by FAO/WHO. Higher metal pollution index values determined for fruits also indicated that TWW application, especially under FI, might cause health risks in long term.

Adoption of Small-Scale Irrigation Farming as a Climate-Smart Agriculture Practice and Its Influence on Household Income in the Chinyanja Triangle, Southern Africa

Directory of Open Access Journals (Sweden)

Nelson Mango

2018-04-01

Full Text Available This article is concerned with the adoption of small-scale irrigation farming as a climate-smart agriculture practice and its influence on household income in the Chinyanja Triangle. Chinyanja Triangle is a region that is increasingly experiencing mid-season dry spells and an increase in occurrence of drought, which is attributed largely to climate variability and change. This poses high agricultural production risks, which aggravate poverty and food insecurity. For this region, adoption of small-scale irrigation farming as a climate-smart agriculture practice is very important. Through a binary logistic and ordinary least squares regression, this article determines factors that influence the adoption of small-scale irrigation farming as a climate-smart agriculture practice and its influence on income among smallholder farmers. The results show that off-farm employment, access to irrigation equipment, access to reliable water sources and awareness of water conservation practices, such as rainwater harvesting, have a significant influence on the adoption of small-scale irrigation farming. On the other hand, the farmer’s age, distance travelled to the nearest market and nature of employment negatively influence the adoption of small-scale irrigation farming decisions. Ordinary least squares regression results showed that the adoption of small-scale irrigation farming as a climate-smart agriculture practice has a significant positive influence on agricultural income. We therefore conclude that to empower smallholder farmers to respond quickly to climate variability and change, practices that will enhance the adoption of small-scale irrigation farming in the Chinyanja Triangle are critical, as this will significantly affect agricultural income. In terms of policy, we recommend that the governments of Zambia, Malawi and Mozambique, which cover the Chinyanja Triangle, formulate policies that will enhance the adoption of sustainable small scale-irrigation

Colostomy irrigation: current knowledge and practice of WOC nurses.

Science.gov (United States)

Cobb, Martha D; Grant, Marcia; Tallman, Nancy J; Wendel, Christopher S; Colwell, Janice; McCorkle, Ruth; Krouse, Robert S

2015-01-01

This study builds on the authors' previous studies that demonstrate that persons living with a colostomy who practice colostomy irrigation (CI) experience quality-of-life benefits. Studies also reveal that patients may not be taught about CI. The purpose of this study was to determine current knowledge, attitudes, and practices of WOC nurses on CI. The target population was ostomy nurses who were members of the Wound, Ostomy and Continence Nurse's Society. Nine hundred eighty-five nurses out of a possible pool of 4191 members responded, providing a response rate of 24%. Their average age was 53 years (range, 25-79 years). Respondents averaged 12 years' experience as a WOC nurse (range, 1-40 years) and 90% (n = 875) were certified. Participants practiced in a variety of settings, including acute and long-term care facilities, home health, and ambulatory clinics. They saw an average of 37 ± 60.5 (mean ± SD) ostomy patients per year (range, 0-1100). A 1-time online survey (SurveyMonkey) of members of the Wound, Ostomy and Continence Nurses (WOCN) Society was conducted. In addition to demographic and educational information, questions also included (1) CI advantages and disadvantages; (2) CI content routinely taught; (3) challenges in assisting patients to learn CI; and (4) where preparation was received for teaching this procedure. Nurses were asked whether they believe CI is evidence-based. More than half identified irrigation as an evidence-based practice (59%), but half indicated they do not routinely teach CI. Multiple factors correlated with nurses' decisions to teach CI, including years of experience (P = .03), specific CI education (P < .001), and considering the intervention evidence-based (P < .001). Factors influencing CI instruction are multifactorial; they include nurses' attitudes, experience base, education, medical indications, setting characteristics, and patient interest and physical abilities. Education on this procedure is urgently needed for

Irrigation Practices, State Intervention and Farmers' Life- Worlds in Drought-Prone Tigray, Ethiopia

NARCIS (Netherlands)

Teshome, W.

2003-01-01

This study examines irrigation practices, state intervention and the responses of farmers in theTigrayregion ofEthiopia

Irrigation water quality and the benefits of implementing good agricultural practices during tomato (Lycopersicum esculentum) production.

Science.gov (United States)

Estrada-Acosta, M; Jiménez, M; Chaidez, C; León-Félix, J; Castro-Del Campo, N

2014-07-01

The implementation of good agricultural practices (GAP) from irrigation water to the tomato packaging process enhances the safety of fresh produce and its value throughout the food chain. The aim of the present study was to show that fresh produce farms that apply and enforce GAP could reduce the presence of Salmonella in finished produce. Samples were collected biweekly from six packing houses from the central region of Sinaloa, México, for the isolation of Salmonella spp by the ISO 6579:2002 method, and the isolated strains were serotyped and genotyped by the Kauffmman-White scheme and pulsed field gel electrophoresis (PFGE), respectively. Salmonella strains were detected in 13 (36.1 %) irrigation water samples, while only two tomato samples were positive (5.5 %). Eight different serotypes were identified in irrigation water, and Salmonella Oranienburg (34 %) was the most prevalent; however, only Salmonella Agona and Salmonella Weltevreden were present on tomatoes. Salmonella Oranienburg was the most widely dispersed and variable serotype, with 10 different PFGE profiles. Salmonella Weltevreden was isolated from both types of samples, albeit with distinct genetic profiles, implying that the sources of contamination differ. These results confirm the utility of implementing good agricultural practices to reduce Salmonella contamination in irrigation water and the packaging process.

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

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.

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.

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.

Safe Re-use Practices in Wastewater-Irrigated Urban Vegetable Farming in Ghana

DEFF Research Database (Denmark)

Keraita, Bernard; Abaidoo, R.C; Beernaerts, I.

2012-01-01

of stakeholders at different levels along the food chain. This paper presents an overview of safe re-use practices including farm-based water treatment methods, water application techniques, post-harvest handling practices, and washing methods. The overview is based on a comprehensive analysis of the literature......Irrigation using untreated wastewater poses health risks to farmers and consumers of crop products, especially vegetables. With hardly any wastewater treatment in Ghana, a multiple-barrier approach was adopted and safe re-use practices were developed through action research involving a number...... and our own specific studies, which used data from a broad range of research methods and approaches. Identifying, testing, and assessment of safe practices were done with the active participation of key actors using observations, extensive microbiological laboratory assessments, and field...

Risk Factors in Chronic Subdural Hematoma: Comparison of Irrigation with Artificial Cerebrospinal Fluid and Normal Saline in a Cohort Analysis

Science.gov (United States)

Adachi, Akihiko; Higuchi, Yoshinori; Fujikawa, Atsushi; Machida, Toshio; Sueyoshi, Shigeo; Harigaya, Kenichi; Ono, Junichi; Saeki, Naokatsu

2014-01-01

Background Chronic subdural hematoma (CSDH) is known to have a substantial recurrence rate. Artificial cerebrospinal fluid (ACF) is an effective irrigation solution in general open craniotomy and endoneurosurgery, but no evidence of its use in burr-hole surgery exists. Objective To identify the potential of ACF irrigation to prevent CSDH recurrence. More specifically, to investigate the perioperative and intraoperative prognostic factors, and to identify controllable ones. Methods To examine various prognostic factors, 120 consecutive patients with unilateral CSDH treated with burr-hole drainage between September 2007 and March 2013 were analyzed. Intraoperative irrigation was performed with one of two irrigation solutions: normal saline (NS; n = 60) or ACF (n = 60). All patients were followed-up for at least 6 months postoperatively. We also examined the morphological alternations of the hematoma outer membranes after incubation with different solutions. Results Eleven patients (9.2%) had recurrence. Nine patients (15%) required additional surgery in the NS group, whereas only 2 patients (3.3%) in the ACF group required additional surgery. Among preoperative and intraoperative data, age (22.0, P = .037), laterality (right, P = .03), and irrigation solution (ACF, P = .027) were related to smaller recurrence rates by log-rank tests. Only the type of irrigation solution used significantly correlated with recurrence in favor of ACF in both Cox proportional hazards (relative hazard: 0.20, 95% confidence interval (CI): 0.04–0.99; P = .049) and logistic regression models (odds ratio, 0.17, 95% CI: 0.03–0.92; P = .04) using these factors. Histological examinations of the hematoma membranes showed that the membranes incubated with NS were loose and infiltrated by inflammatory cells compared with those incubated with ACF. Conclusion Irrigation with ACF decreased the rate of CSDH recurrence. PMID:25089621

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

Quality of white cabbage yield and potential risk of ground water nitrogen pollution, as affected by nitrogen fertilisation and irrigation practices.

Science.gov (United States)

Maršić, Nina Kacjan; Sturm, Martina; Zupanc, Vesna; Lojen, Sonja; Pintar, Marina

2012-01-15

The effect of different fertilisation (broadcast solid NPK application and fertigation with water-soluble fertiliser) and irrigation practices (sprinkler and drip irrigation) on yield, the nitrate content in cabbage (Brassica oleracea var. capitata L.) and the cabbage N uptake was detected, in order to assess the potential risk for N losses, by cultivation on sandy-loam soil. The N rate applied on the plots was 200 kg N ha(-1). The highest yield (93 t ha(-1)) and nitrate content (1256 mg kg(-1) DW) were found with treatments using broadcast fertilisation and sprinkler irrigation. On those plots the negative N balance (-30 kg N ha(-1)) was recorded, which comes mainly from the highest crop N uptake (234 kg N ha(-1)) indicating the lowest potential for N losses. In terms of yield quality and the potential risk for N losses, broadcast fertilisation combined with sprinkler irrigation proved to be the most effective combination among the tested practices under the given experimental conditions. The importance of adequate irrigation is also evident, namely in plots on which 50% drip irrigation was applied, the lowest yield was detected and according to the positive N balance, a higher potential for N losses is expected. Copyright © 2011 Society of Chemical Industry.

The effects of bud load and regulated deficit irrigation on sugar, organic acid, phenolic compounds and antioxidant activity of Razakı table grape berries

Directory of Open Access Journals (Sweden)

Tangolar Semih

2015-01-01

Full Text Available This study aims at assessing the effects of increased bud load and irrigation applications on berry quality of the Razakı table grape. Two Regulated Deficit Irrigation (RDI having different irrigation levels (RDI-I and RDI-II based on the growth stages, in addition to a non-irrigated control treatment together with two different bud load practices (K-normal and 2K-two-fold buds of the normal were examined for their effects on quality attributes such as sugar and organic acids contents, phenolic compounds as well as antioxidant capacity of the berries. The non-irrigated vines had highest sugar level (198.86 g/kg in the first year (2013 of the experiment whilst the sugar content of the berries was increased with irrigation (RDI-II in 2014. However the highest organic acid (7.10 g/kg was recorded from the RDI-II treatment in 2013 whereas those of from non-irrigated vines were highest (7.81 g/kg in 2014. Considering the sugar and organic acid content of the berries, bud load effects were not significant. The total phenolic acids were higher under non-irrigated and 2K bud load conditions. Antioxidant activity of berries was increased with RDI-I irrigation and 2K practices in the first year (2013 although no significant effect was recorded in the second year of the experiment. In all applications, glucose among the sugars, tartaric acid among the organic acids, catechin and epicatechin among the phenolic compounds were detected to be higher compared to other components in berries.

Loss of surface horizon of an irrigated soil detected by radiometric images of normalized difference vegetation index.

Science.gov (United States)

Fabian Sallesses, Leonardo; Aparicio, Virginia Carolina; Costa, Jose Luis

2017-04-01

The use of the soil in the Humid Pampa of Argentina has changed since the mid-1990s from agricultural-livestock production (that included pastures with direct grazing) to a purely agricultural production. Also, in recent years the area under irrigation by central pivot has been increased to 150%. The waters used for irrigation are sodium carbonates. The combination of irrigation and rain increases the sodium absorption ratio of soil (SARs), consequently raising the clay dispersion and reducing infiltration. This implies an increased risk of soil loss. A reduction in the development of white clover crop (Trifolium repens L.) was observed at an irrigation plot during 2015 campaign. The clover was planted in order to reduce the impact of two maize (Zea mays L.) campaigns under irrigation, which had increased soil SAR and deteriorated soil structure. SPOT-5 radiometric normalized difference vegetation index (NDVI) images were used to determine two zones of high and low production. In each zone, four random points were selected for further geo-referenced field sampling. Two geo-referenced measures of effective depth and surface soil sampling were carried out in each point. Texture of soil samples was determined by Pipette Method of Sedimentation Analysis. Data exploratory analysis showed that low production zone had a media effective depth = 80 cm and silty clay loam texture, while high production zone had a media effective depth > 140 cm and silt loam texture. The texture class of the low production zone did not correspond to prior soil studies carried out by the INTA (National Institute of Agricultural Technology), which showed that those soil textures were silt loam at surface and silty clay loam at sub-surface. The loss of the A horizon is proposed as a possible explanation, but further research is required. Besides, the need of a soil cartography actualization, which integrates new satellite imaging technologies and geo-referenced measurements with soil sensors is

Field Evidence Supporting Conventional Onion Curing Practices as a Strategy To Mitigate Escherichia coli Contamination from Irrigation Water.

Science.gov (United States)

Wright, Daniel; Feibert, Erik; Reitz, Stuart; Shock, Clint; Waite-Cusic, Joy

2018-03-01

The Produce Safety Rule of the U.S. Food Safety Modernization Act includes restrictions on the use of agricultural water of poor microbiological quality. Mitigation options for poor water quality include the application of an irrigation-to-harvest interval of onion production includes an extended irrigation-to-harvest interval (onion fields (randomized block design; n = 5) via drip tape on the final day of irrigation. Onions remained undisturbed for 7 days and were then lifted to the surface to cure for an additional 21 days before harvest. Water, onions, and soil were tested for presence of rifampin-resistant E. coli. One day after irrigation, 13.3% of onions (20 of 150) receiving the poorest quality water (3 log CFU/mL) tested positive for E. coli; this prevalence was reduced to 4% (6 of 150 onions) after 7 days. Regardless of inoculum level, E. coli was not detected on any onions beyond 15 days postirrigation. These results support conventional dry bulb onion curing practices as an effective strategy to mitigate microbiological concerns associated with poor quality irrigation water.

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.

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...

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.

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

Water deficit imposed by partial irrigation at different plant growth stages of common bean

International Nuclear Information System (INIS)

Calvache, M.; Reichardt, K.

1995-01-01

The purpose of this study was to identify specific growth stages of common bean crop, at which the plant is less sensitive to water stress so that irrigation can be omitted without significant decrease in biological nitrogen fixation and yield. Two field experiments were conducted at a University experiments station, Tumbaco, Pichincha, Ecuador, on a sandy loam soil ( Typic durustoll ). The climate is warm and dry ( mean air temperature 16 degree Celcius and mean relative humidity 74% ) during the cropping season and rainfall of 123 mm was recorded during the cropping period. The treatments consisted of combinations of 7 irrigation regimes ( I1 = all normal watering; I2 = all stres; I3 = traditional practice; I4 = single stress at vegetation; I5 flowering; I6 = yield formation and I7 = ripening stages ) and 2 levels of applied N ( 20 and 80 kg/ ha ). Differential irrigation was started after 3 uniform irrigations for germination and crop establishment. Soil moisture was monitored with a neutron probe down to 0.60 m depth, before and 24 h after each irrigation. Biological Nitrogen Fixation was calculated using the N- 15 metodology in the 20 kg N/ ha treatment. From the yield data, it can be concluded that treatments which had irrigation deficit had lower yield than those that had suplementary irrigation. The flowering stage was the most sensitive to number of pods and grain yield. Biological Nitrogen Fixation was significantly affected by water stress at flowering and formation stages. The crop water use efficiency ( kg/ m 3 ) was the lowest at flowering period and the yield response factor ( Ky ) was higher in treatments I2 ( all stress ) and I5 (stress at flowering ). Comparing with traditional practice by farmers of the region, only treatments I1 and I7 had 13 and 10 % higher crop water use effeciency. 15 tabs., 7 refs. ( Author )

Rice production with minimal irrigation and no nitrogen fertilizer by intensive use of treated municipal wastewater.

Science.gov (United States)

Muramatsu, Ayumi; Watanabe, Toru; Sasaki, Atsushi; Ito, Hiroaki; Kajihara, Akihiko

2014-01-01

We designed a new cultivation system of rice with circulated irrigation to remove nitrogen from treated municipal wastewater effectively and assessed the possibility of nitrogen removal in the new system without any adverse effects on rice production through bench-scale experiments through two seasons. Overgrowth of the rice plant, which can lead to lodging and tasteless rice, was found in the first season probably because nitrogen supply based on standard practice in normal paddy fields was too much in the closed irrigation system. In the second season, therefore, the amount of treated wastewater initially applied to the system was reduced but this resulted in a considerably decreased yield. On the other hand, the taste of the rice was significantly improved. The two-season experiments revealed that the new system enabled rice production with minimal irrigation (approximately 50% on the yield base compared to normal paddy fields) and no nitrogen fertilizer. The system also achieved >95% removal of nitrogen from the treated wastewater used for circulated irrigation. The accumulation of harmful metals in the rice was not observed after one season of cultivation in the new system. The accumulation after cultivation using the same soil repeatedly for a longer time should be examined by further studies.

Effects of Aquifer Development and Changes in Irrigation Practices on Ground-Water Availability in the Santa Isabel Area, Puerto Rico

Science.gov (United States)

Kuniansky, Eve L.; Gómez-Gómez, Fernando; Torres-Gonzalez, Sigfredo

2003-01-01

The alluvial aquifer in the area of Santa Isabel is located within the South Coastal Plain aquifer of Puerto Rico. Variations in precipitation, changes in irrigation practices, and increasing public-supply water demand have been the primary factors controlling water-level fluctuations within the aquifer. Until the late 1970s, much of the land in the study area was irrigated using inefficient furrow flooding methods that required large volumes of both surface and ground water. A gradual shift in irrigation practices from furrow systems to more efficient micro-drip irrigation systems occurred between the late 1970s and the late 1980s. Irrigation return flow from the furrow-irrigation systems was a major component of recharge to the aquifer. By the early 1990s, furrow-type systems had been replaced by the micro-drip irrigation systems. Water levels declined about 20 feet in the aquifer from 1985 until present (February 2003). The main effect of the changes in agricultural practices is the reduction in recharge to the aquifer and total irrigation withdrawals. Increases in ground-water withdrawals for public supply offset the reduction in ground-water withdrawals for irrigation such that the total estimated pumping rate in 2003 was only 8 percent less than in 1987. Micro-drip irrigation resulted in the loss of irrigation return flow to the aquifer. These changes resulted in lowering the water table below sea level over most of the Santa Isabel area. By 2002, lowering of the water table reversed the natural discharge along the coast and resulted in the inland movement of seawater, which may result in increased salinity of the aquifer, as had occurred in other parts of the South Coastal Plain. Management alternatives for the South Coastal Plain aquifer in the vicinity of Santa Isabel include limiting groundwater withdrawals or implementing artificial recharge measures. Another alternative for the prevention of saltwater intrusion is to inject freshwater or treated sewage

Manufacturing technology for practical Josephson voltage normals

International Nuclear Information System (INIS)

Kohlmann, Johannes; Kieler, Oliver

2016-01-01

In this contribution we present the manufacturing technology for the fabrication of integrated superconducting Josephson serial circuits for voltage normals. First we summarize some foundations for Josephson voltage normals and sketch the concept and the setup of the circuits, before we describe the manufacturing technology form modern practical Josephson voltage normals.

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

Effects of changing irrigation practices on the ground-water hydrology of the Santa Isabel-Juana Diaz area, south central Puerto Rico

Science.gov (United States)

Ramos-Gines, Orlando

1994-01-01

Prior to 1930, the principal source of water for irrigation in the Santa Isabel-Juana Diaz area was surface water from outside the study area, which was delivered by a complex channel-pond system. Recharge from water applied to the fields, estimated to be 18.7 million of gallons per day, and discharge by ground-water flow to sea, estimated to be 17 million of gallons per day, were the major water- budget components prior to intensive development of the ground-water resources. Development of the ground-water resources after 1930 resulted in a substantial increase in irrigation, primarily furrow irrigation. The surface water supplied by the complex channel-pond system continued to be used and ground-water withdrawals increased sub- stantially. By 1966-68, ground-water recharge from irrigation water applied to the fields, estimated to be 37 million of gallons per day, and discharge by pumpage for irrigation, estimated to be 77 million of gallons per day, were the two major components of the ground-water budget. By 1987, drip irrigation had become the principal method of irrigation in the study area, and surface-water irrigation had, for the most part, been discontinued. The estimated aquifer recharge from irrigation water in 1987 was about 6.6 million of gallons per day, which occurred primarily in the remaining fields where furrow irrigation was still practiced. Although aquifer recharge had been reduced as a result of the conversion from furrow to drip irrigation, water levels in the aquifer were higher in 1987 than in 1968 because of the large reduction in ground-water withdrawals and subsequent recovery of ground-water levels.

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.

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.

Irrigation practices in long-term survivors of colorectal cancer with colostomies.

Science.gov (United States)

Grant, Marcia; McMullen, Carmit K; Altschuler, Andrea; Hornbrook, Mark C; Herrinton, Lisa J; Wendel, Christopher S; Baldwin, Carol M; Krouse, Robert S

2012-10-01

For some patients diagnosed with rectal cancer, surgery will involve the creation of a temporary or permanent ostomy. When the colostomy is located in the sigmoid or descending colon, regulation of fecal output can occur through irrigation, a procedure that involves instilling fluid into the bowel to flush out gas and fecal material. When successfully used, irrigation can prevent fecal output between irrigations, providing some control over colostomy output. The purpose of this article is to describe participants of a large, multisite, multi-investigator study of health-related quality of life in long-term colorectal cancer survivors who answered questions about colostomy irrigation and reported the potential advantages and disadvantages of the procedure. The article also will explore healthcare professionals' role in ensuring patients and family members are educated and well informed about their options regarding temporary or permanent ostomies.

Effect of irrigation techniques and strategies on water footprint of growing crops

Science.gov (United States)

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

2014-12-01

Reducing the water footprint (WF) of growing crops, the largest water user and a significant contributor to the WF of many consumer products, plays a significant role in integrated and sustainable water management. The water footprint for growing crop is accounted by relating the crop yield with the corresponding consumptive water use (CWU), which both can be adjusted by measures that affect the crop growth and root-zone soil water balance. This study explored the scope for reducing the water footprint of irrigated crops by experimenting set of field level technical and managerial measures: (i) irrigation technologies (Furrow, sprinkler, drip and sub-surface drip), (ii) irrigation strategies (full and a range of sustained and controlled deficit) and (iii) field management options (zero, organic and synthetic mulching). Ranges of cases were also considered: (a) Arid and semi-arid environment (b) Loam and Sandy-loam soil types and (c) for Potato, Wheat and Maize crops; under (c) wet, normal and dry years. AquaCrop, the water driven crop growth and soil water balance model, offered the opportunity to systematically experiment these measures on water consumption and yield. Further, the green and blue water footprints of growing crop corresponding to each measure were computed by separating the root zone fluxes of the AquaCrop output into the green and blue soil water stocks and their corresponding fluxes. Results showed that in arid environment reduction in irrigation supply, CWU and WF up to 300 mm, 80 mm and 75 m3/tonne respectively can be achieved for Maize by a combination of organic mulching and drip technology with controlled deficit irrigation strategies (10-20-30-40% deficit with reference to the full irrigation requirement). These reductions come with a yield drop of 0.54 tonne/ha. In the same environment under the absence of mulching practice, the sub-surface drip perform better in reducing CWU and WF of irrigated crops followed by drip and furrow irrigation

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...

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...

Climate forcing and desert malaria: the effect of irrigation.

Science.gov (United States)

Baeza, Andres; Bouma, Menno J; Dobson, Andy P; Dhiman, Ramesh; Srivastava, Harish C; Pascual, Mercedes

2011-07-14

Rainfall variability and associated remote sensing indices for vegetation are central to the development of early warning systems for epidemic malaria in arid regions. The considerable change in land-use practices resulting from increasing irrigation in recent decades raises important questions on concomitant change in malaria dynamics and its coupling to climate forcing. Here, the consequences of irrigation level for malaria epidemics are addressed with extensive time series data for confirmed Plasmodium falciparum monthly cases, spanning over two decades for five districts in north-west India. The work specifically focuses on the response of malaria epidemics to rainfall forcing and how this response is affected by increasing irrigation. Remote sensing data for the Normalized Difference Vegetation Index (NDVI) are used as an integrated measure of rainfall to examine correlation maps within the districts and at regional scales. The analyses specifically address whether irrigation has decreased the coupling between malaria incidence and climate variability, and whether this reflects (1) a breakdown of NDVI as a useful indicator of risk, (2) a weakening of rainfall forcing and a concomitant decrease in epidemic risk, or (3) an increase in the control of malaria transmission. The predictive power of NDVI is compared against that of rainfall, using simple linear models and wavelet analysis to study the association of NDVI and malaria variability in the time and in the frequency domain respectively. The results show that irrigation dampens the influence of climate forcing on the magnitude and frequency of malaria epidemics and, therefore, reduces their predictability. At low irrigation levels, this decoupling reflects a breakdown of local but not regional NDVI as an indicator of rainfall forcing. At higher levels of irrigation, the weakened role of climate variability may be compounded by increased levels of control; nevertheless this leads to no significant decrease

Prospects and Constraints of Household Irrigation Practices ...

African Journals Online (AJOL)

Water and soil samples were analyzed for major cations and anions, ... So, attention and investment in these areas have been very limited in Africa and ... The shape of the watershed is almost elliptical (Fig. 1). 2.1. Soil. Texturally ..... quality of the irrigation water, soil factors such as structure, degree of compaction, organic.

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)

Socio-economic impacts of irrigated agriculture in Mbarali District of south west Tanzania

Science.gov (United States)

Mwakalila, Shadrack

Irrigation has been found to be central in curbing food scarcity not only in Tanzania but also in many other developing countries. It has been proved that continued reliability on rainfall in agriculture cannot sustain the increase in population. This study examines the impacts of smallholder irrigated agriculture in improving social and economic benefits in Igurusi Ward of Mbarali District which is located in the southern-western part of Tanzania. The study applies the Participatory Rural Appraisal Framework for data collection. The study was confined to five villages in Igurusi ward which are Majenje, Igurusi, Chamoto, Uhambule and Mahango. The study examined critically paddy production for smallholder farmers that practice irrigation and those who cultivates rain-fed paddy. The study examined both existing traditional and modern irrigation systems. It was found that, most of the respondents (79%) practice irrigated agriculture in paddy production while the remaining 21% practice rain-fed agriculture. Forty percent of households that practice irrigated agriculture harvest paddy two seasons per year. The return to labour in paddy production for smallholder farmers who irrigate their paddy fields is about US 2.5/manday which is above the poverty line of US 1.0/day. The smallest return to labour (US $ 0.85/manday) is obtained by an average smallholder farmer who cultivates rain-fed paddy using hand hoe and family labour. The potential implication of the current irrigation systems is that if irrigation is managed properly it may lead to sustainable increases in small farmer’s productivity and income, thus alleviating rural poverty.

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

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

Mapping irrigated areas in Afghanistan over the past decade using MODIS NDVI

Science.gov (United States)

Pervez, Md Shahriar; Budde, Michael; Rowland, James

2014-01-01

Agricultural production capacity contributes to food security in Afghanistan and is largely dependent on irrigated farming, mostly utilizing surface water fed by snowmelt. Because of the high contribution of irrigated crops (> 80%) to total agricultural production, knowing the spatial distribution and year-to-year variability in irrigated areas is imperative to monitoring food security for the country. We used 16-day composites of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to create 23-point time series for each year from 2000 through 2013. Seasonal peak values and time series were used in a threshold-dependent decision tree algorithm to map irrigated areas in Afghanistan for the last 14 years. In the absence of ground reference irrigated area information, we evaluated these maps with the irrigated areas classified from multiple snapshots of the landscape during the growing season from Landsat 5 optical and thermal sensor images. We were able to identify irrigated areas using Landsat imagery by selecting as irrigated those areas with Landsat-derived NDVI greater than 0.30–0.45, depending on the date of the Landsat image and surface temperature less than or equal to 310 Kelvin (36.9 ° C). Due to the availability of Landsat images, we were able to compare with the MODIS-derived maps for four years: 2000, 2009, 2010, and 2011. The irrigated areas derived from Landsat agreed well r2 = 0.91 with the irrigated areas derived from MODIS, providing confidence in the MODIS NDVI threshold approach. The maps portrayed a highly dynamic irrigated agriculture practice in Afghanistan, where the amount of irrigated area was largely determined by the availability of surface water, especially snowmelt, and varied by as much as 30% between water surplus and water deficit years. During the past 14 years, 2001, 2004, and 2008 showed the lowest levels of irrigated area (~ 1.5 million hectares), attesting to

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.)

Prácticas para estimular el parto normal Practices to stimulate normal childbirth

Directory of Open Access Journals (Sweden)

Flora Maria Barbosa da Silva

2011-09-01

Full Text Available Este artículo lleva a una reflexión sobre las prácticas del estímulo al parto normal, con la fundamentación teórica de cada una de ellas. Las prácticas incluidas en este estudio fueron el ayuno, enemas, spray y baños de inmersión, caminatas, movimientos pélvicos y masaje. En un contexto de revalorización del parto normal, ofrecer a la mujer durante el parto opciones de comodidad basadas en evidencias puede ser una forma de preservar el curso fisiológico del parto.This article leads to a reflection about the practices of encouraging normal childbirth, with the theoretical foundation for each one of them. The practices included in this study were fasting, enema, shower and immersion baths, walking, pelvic movements and massage. In a context of revaluation of normal birth, providing evidence-based comfort options for women during childbirth can be a way to preserve the physiological course of labour.

Effects of fertilisation and irrigation practices on yield, maturity and storability of onions

Directory of Open Access Journals (Sweden)

T. SUOJALA

2008-12-01

Full Text Available The study aimed to establish whether a high onion yield and good storage performance could be obtained with low fertilisation rates if irrigation was applied when necessary. Two-year experiments investigated the effects of three NPK fertiliser levels (N 50, 100, 125/150 kg/ha, with and without irrigation, on yield, advancement of maturity, storage losses and shelf life. High fertilisation advanced maturity but irrigation had no effect. High fertilisation increased yield only in 1996 (5B7%, but irrigation increased the yield noticeably: by 33.5% in 1995 and 8.5% in 1996. There was no interaction between fertilisation and irrigation. The low fertilisation optimum is attributed to the mineralisation of soil nitrogen, as the soil was rich in organic matter. At the low fertilisation level, plants took up twice as much nitrogen as present in the fertiliser, and with increased fertilisation the nitrogen uptake increased markedly. The foliage nitrogen content was low, evidently as a result of late harvesting. Treatments had only a minor effect on the storage performance and shelf life of onions. The results suggest that fertilisation rates could be reduced in onion production. Irrigation during warm and dry periods is essential to achieve the maximum yield potential and does not impair the storage quality of onions.;

Participatory innovation process for testing new practices for soil fertility management in Chókwè Irrigation Scheme (Mozambique)

Science.gov (United States)

Sánchez Reparaz, Maite; de Vente, Joris; Famba, Sebastiao; Rougier, Jean-Emmanuel; Ángel Sánchez-Monedero, Miguel; Barberá, Gonzalo G.

2015-04-01

Integrated water and nutrient management are key factors to increase productivity and to reduce the yield gap in irrigated systems in Sub-Saharan Africa. These two elements are affected by an ensemble of abiotic, biotic, management and socio-economic factors that need to be taken into account to reduce the yield gap, as well as farmers' perceptions and knowledge. In the framework of the project European Union and African Union cooperative research to increase Food production in irrigated farming systems in Africa (EAU4Food project) we are carrying out a participatory innovation process in Chókwè irrigation scheme (Mozambique) based on stakeholders engagement, to test new practices for soil fertility management that can increase yields reducing costs. Through a method combining interviews with three farmers' associations and other relevant stakeholders and soil sampling from the interviewed farmers' plots with the organization of Communities of Practices, we tried to capture how soil fertility is managed by farmers, the constraints they find as well as their perceptions about soil resources. This information was the basis to design and conduct a participatory innovation process where compost made with rice straw and manure is being tested by a farmers' association. Most important limitations of the method are also evaluated. Our results show that socio-economic characteristics of farmers condition how they manage soil fertility and their perceptions. The difficulties they face to adopt new practices for soil fertility management, mainly related to economic resources limitations, labour availability, knowledge time or farm structure, require a systemic understanding that takes into account abiotic, biotic, management and socio-economic factors and their implication as active stakeholders in all phases of the innovation process.

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.

to Irrigation Intervals and Plant Density in Zuru, Northern Guinea

African Journals Online (AJOL)

ISSN 0794-5698. Response of Onion (Allium cepa L.) to Irrigation Intervals and Plant Density in ... The treatments were laid out in a split plot design with three replications. Irrigation ..... System and Agronomic Practice in. Tropical Climates.

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

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.

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

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)

Precision overhead irrigation is suitable for several Central Valley crops

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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.

Influence of sustainable irrigation regimes and agricultural practices on the soil CO2 fluxes from olive groves in SE Spain

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Marañón-Jiménez, Sara; Serrano-Ortíz, Penelope; Vicente-Vicente, Jose Luis; Chamizo, Sonia; Kowalski, Andrew S.

2017-04-01

Olive (Olea europaea) is the dominant agriculture plantation in Spain and its main product, olive oil, is vital to the economy of Mediterranean countries. Given the extensive surface dedicated to olive plantations, olive groves can potentially sequester large amounts of carbon and contribute to mitigate climate change. Their potential for carbon sequestration will, however, largely depend on the management and irrigation practices in the olive grove. Although soil respiration is the main path of C release from the terrestrial ecosystems to the atmosphere and a suitable indicator of soil health and fertility, the interaction of agricultural management practices with irrigation regimes on soil CO2 fluxes have not been assessed yet. Here we investigate the influence of the presence of herbaceous cover, use of artificial fertilizers and their interaction with the irrigation regime on the CO2 emission from the soil to the atmosphere. For this, the three agricultural management treatments were established in replicated plots in an olive grove in the SE of Spain: presence of herbaceous cover ("H"), exclusion of herbaceous cover by using herbicides ("NH"), and exclusion of herbaceous cover along with addition of artificial fertilizers (0.55 kg m-2 year-1 of N, P, K solid fertilizer in the proportion 20:10:10, "NHF"). Within each management treatment, three irrigation regimes were also implemented in a randomized design: no-irrigation ("NO") or rain fed, full irrigation (224 l week-1 per olive tree, "MAX"), and a 50% restriction (112 l week-1 per olive tree, "MED"). Soil respiration was measured every 2-3 weeks at 1, 3, and 5 meters from each olive tree together with soil temperature and soil moisture in order to account for the spatial and seasonal variability over the year. Soil respiration was higher when herbaceous cover was present compared to the herbaceous exclusion, whereas the addition of fertilizer did not exert any significant effect. Although the different

Identification and Prioritization of Management Practices to Reduce Methylmercury Exports from Wetlands and Irrigated Agricultural Lands

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McCord, Stephen A.; Heim, Wesley A.

2015-03-01

The Sacramento-San Joaquin Delta's (Delta) beneficial uses for humans and wildlife are impaired by elevated methylmercury (MeHg) concentrations in fish. MeHg is a neurotoxin that bioaccumulates in aquatic food webs. The total maximum daily load (TMDL) implementation plan aimed at reducing MeHg in Delta fish obligates dischargers to conduct MeHg control studies. Over 150 stakeholders collaborated to identify 24 management practices (MPs) addressing MeHg nonpoint sources (NPS) in three categories: biogeochemistry (6), hydrology (14), and soil/vegetation (4). Land uses were divided into six categories: permanently and seasonally flooded wetlands, flooded and irrigated agricultural lands, floodplains, and brackish-fresh tidal marshes. Stakeholders scored MPs based on seven criteria: scientific certainty, costs, MeHg reduction potential, spatial applicability, technical capacity to implement, negative impacts to beneficial uses, and conflicting requirements. Semi-quantitative scoring for MPs applicable to each land use (totaling >400 individual scores) led to consensus-based prioritization. This process relied on practical experience from diverse and accomplished NPS stakeholders and synthesis of 17 previous studies. Results provide a comprehensive, stakeholder-driven prioritization of MPs for wetland and irrigated agricultural land managers. Final prioritization highlights the most promising MPs for practical application and control study, and a secondary set of MPs warranting further evaluation. MPs that address hydrology and soil/vegetation were prioritized because experiences were positive and implementation appeared more feasible. MeHg control studies will need to address the TMDL conundrum that MPs effective at reducing MeHg exports could both exacerbate MeHg exposure and contend with other management objectives on site.

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.

[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.

Automated cycled sprinkler irrigation for spring frost protection of cranberries

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Sprinkler irrigation is essential for preventing spring frost bud damage in cranberry (Vaccinium macrocarpon Ait). Risk-averse growers have been reluctant to adopt the intermittent cycling of irrigation pumps as a standard management practice. In the spring of 2013 and 2014, an experiment was conduc...

Chlorophyll meter for estimating nitrogen status of irrigated wheat

International Nuclear Information System (INIS)

Schepers, J.S.

2000-01-01

Chlorophyll-meter readings, generated from the leaves of irrigated wheat at particular growth stages, were normalized to the data obtained with locally recommended rates of fertilizer N, in Chile China, India and Mexico. Normalizing permitted comparisons of crop-N status across growth stages, locations, cultivars, and years. Relative yields and meter readings at growth-stage Z-50 are presented; they revealed similar trends for India, China, and Chile, however, for Mexico, the combination of soil, wheat cultivar, and climate resulted in much less response to N fertilization in the meter data. The implications are discussed. The SPAD meter proved to be a good tool to monitor and evaluate the N status of irrigated wheat. (author)

Automation in irrigation process in family farm with Arduino platform

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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.

Root Zone Sensors for Irrigation Management in Intensive Agriculture

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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.

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.

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.

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.

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.

Assessing the efficacy of the SWAT auto-irrigation function to simulate Irrigation, evapotranspiration and crop response to irrigation management strategies of the Texas High Plains

Science.gov (United States)

The Soil and Water Assessment Tool (SWAT) model is widely used for simulation of hydrologic processes at various temporal and spatial scales. Less common are long-term simulation analyses of water balance components including agricultural management practices such as irrigation management. In the se...

Speed control variable rate irrigation

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Speed control variable rate irrigation (VRI) is used to address within field variability by controlling a moving sprinkler’s travel speed to vary the application depth. Changes in speed are commonly practiced over areas that slope, pond or where soil texture is predominantly different. Dynamic presc...

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

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.

Dissemination of sustainable irrigation strategies for almond and olive orchards via a participatory approach. Project LIFE+IRRIMAN

Science.gov (United States)

Garcia-Vila, Margarita; Gamero-Ojeda, Pablo; Ascension Carmona, Maria; Berlanga, Jose; Fereres, Elias

2017-04-01

Dissemination of sustainable irrigation strategies for almond and olive orchards via a participatory approach. Project LIFE+IRRIMAN Spain is the world's first and third largest producer of olive oil and almond, respectively. Despite huge efforts in the last years by the production sector towards intensification, cultural issues relative to the traditional rain-fed crop management know how, prevent farmers from adoption of sustainable irrigation management practices. Consequently, even though there has been progress in irrigation management research for these two crops, adoption of modern irrigation techniques by farmers has been slow. Sustainable irrigation strategies for olive and almond orchards are being designed, implemented, validated and disseminated under the framework of the LIFE+ IRRIMAN project, through a participatory approach. The implementation of the LIFE+ IRRIMAN innovative and demonstrative actions has been carried out in an irrigation district of Southern Spain (Genil-Cabra Irrigation Scheme, Andalusia). The approach designed has four phases: i) design and implementation of sustainable irrigation strategies in demonstration farms; ii) dissemination of best irrigation practices which were tested in the initial year throughout the irrigation scheme by the irrigation advisory service; iii) assessment of degree of adoption and re-design of the dissemination strategies; and, iv) based on the results obtained, elaboration of sustainable irrigation guidelines for knowledge transfer in the district at regional and national levels to promote changes in irrigation practices. Participatory approaches have proven to be effective tools for successful irrigation strategies design and diffusion, especially in traditional rain fed crops such as olive and almond trees in the Mediterranean countries. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

Normal tension glaucoma management: a survey of contemporary practice.

Science.gov (United States)

Symes, Richard J; Mikelberg, Frederick S

2017-08-01

The aim of this study was to investigate contemporary practice patterns with respect to normal tension glaucoma (NTG) management and to determine whether the 2 largest NTG trials have influenced ophthalmologists' clinical practice. A survey questionnaire was sent to ophthalmologists via the American Glaucoma Society, the Canadian Glaucoma Society, and the Canadian Ophthalmological Society. The questionnaire was designed to investigate ophthalmologists' usual practice with respect to NTG and the extent to which practice has been influenced by the Collaborative Normal Tension Glaucoma Study (CNTGS) and the Low pressure Glaucoma Treatment Study (LoGTS). In total, 419 ophthalmologists completed the survey. Of these, 264 respondents were glaucoma subspecialists. The survey showed that 95% and 64% of ophthalmologists were familiar with the CNTGS and the LoGTS, respectively. Of the respondents, 70% indicated that they would initiate treatment in mild-to-moderate NTG without waiting for documented disease progression. Of the respondents, 61% of the total surveyed and 50% of the glaucoma subspecialists felt that the LoGTS results had no impact on their usual clinical practice. The first-choice topical drug for NTG was a prostaglandin analogue (88% of respondents) or brimonidine (10% of respondents). Most ophthalmologists treat NTG more aggressively than recommended by the CTNGS protocol. Most ophthalmologists felt that the LoGTS results had no impact on their normal clinical practice. The prostaglandin analogues are, by far, the most popular choice of drug for contemporary management of NTG. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Aspects of irrigation development in the Netherlands East Indies

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Maurits W. Ertsen

2006-04-01

Full Text Available The ‘Romijn’ discharge measurement structure was developed in the Netherlands East Indies. By the end of the colonial period in the 1930s, it had become the standard structure in irrigation. The Romijn design is not only still the main discharge measurement structure in Indonesia, it is also used in Dutch water management practice and education. The question of continuity is at the heart of concepts such as ‘technological tradition’ or ‘technological regime’, and this continuity links the information embodied in a community of practitioners with the hardware and software the members master. Such communities define accepted modes of technical operation. Engineering education is an important mechanism in preference-guided selection of design solutions, and obtaining an engineering degree is much like passing the preparatory requirements for community membership. When, in 1967, a civil engineering student from Delft Polytechnic presented his final paper for an irrigation design to his supervisors, the first question they asked was why he had not used a Romijn weir as an off-take structure. The Dutch irrigation regime, which consists of the explicit and implicit rules of Dutch irrigation design, is the central subject of this paper. In this paper I shall discuss two related issues: (1 how the Netherlands East Indies irrigation regime developed, and (2 how the (discontinuities in irrigation education and practice following Indonesian independence can be understood. Naturally, while discussion of these issues, to a certain extent at least, depends on the data available, it also depends on the researcher’s perspective.

Various irrigation fluids affect postoperative brain edema and cellular damage during experimental neurosurgery in rats.

Science.gov (United States)

Doi, Kazuhisa; Kawano, Takeshi; Morioka, Yujiro; Fujita, Yasutaka; Nishimura, Masuhiro

2006-12-01

This study was conducted to investigate how various irrigation fluids used during neurosurgical procedures affect the degree of postoperative brain edema and cellular damage during experimental neurosurgery in rats. The cerebral cortex was exposed and incised crosswise with a surgical knife under irrigation with an artificial CSF, lactated Ringer's solution, or normal saline. Four hours after injury, irrigation was stopped and brain tissue samples were obtained from injured and uninjured sites. Specific gravity, cerebrovascular permeability, and TTC staining of the samples were evaluated. Incision and irrigation of the brain were not performed on the control group. At the injured site, specific gravities of the samples in the normal saline group and the lactated Ringer's solution group were significantly lower than the specific gravity in the artificial CSF group. The EB concentration was significantly higher in the lactated Ringer's solution group and relatively high in the normal saline group as compared with the artificial CSF group. TTC staining did not differ significantly between the artificial CSF group and the control group. It was significantly lower in the lactated Ringer's solution group and the normal saline group than in the control group and the artificial CSF group. As compared with normal saline and lactated Ringer's solution, artificial CSF reduced postoperative brain edema, cerebrovascular permeability, and cellular damage in sites injured by experimental neurosurgery in rats.

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

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Sh Rezvan Beidokhti

2012-10-01

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

Character Association and Path Analysis of Black Cumin (Nigella sativa L. Genotypes under Different Irrigation Regimes

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Kaosar BARDIDEH

2013-02-01

Full Text Available Character association and path analysis were performed for black seed cultivars using a split-plots design based on RCBD with three replications. Three cultivars (‘Varzaneh’, ‘Semirom’ and ‘Mobarakeh’ were studied under three levels of irrigation (normal irrigation, irrigation with drought stress before and after flowering. Under normal and abnormal irrigations the relation of seed yield and three characters biological yield, number of capsule per plant and thousand seed weight were high, positive significantly (p≤0.01; the relation between yield and number of sub branch was positive significantly (p≤0.05. In terms of abnormal irrigation there was a positive significant correlation between essence percent and yield (p≤0.05. Under normal irrigation the most direct effect of traits on yield was obtained from biological yield (0.778 followed the number of capsules per plant (0.245. The most indirect effect of traits on yield was obtained from biological yield through thousand seed weight (0.576 followed stem diameter through biological yield (0.468. Under water deficiency conditions the most direct effect of traits on yield was obtained from biological yield (0.811 followed the number of capsules per plant (0.231. The most indirect effect of traits on yield was obtained from biological yield through thousand seed weight (0.562.

Evaluating the impact of irrigation on surface water - groundwater interaction and stream temperature in an agricultural watershed.

Science.gov (United States)

Essaid, Hedeff I; Caldwell, Rodney R

2017-12-01

Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures

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.

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

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

Phosphorus absorption in drip irrigation

International Nuclear Information System (INIS)

Guennelon, R.; Habib, R.

1979-01-01

Introducing the use of solute phosphate with drip irrigation may be an unsatisfying practice on account of the very weak mobility of PO 4 anion. Nevertheless P can move down to 30-40 cm depth by following the saturated flux along earth-worms holes or crakes, or by displacement in very narrow structural porosity, even in heavy soils. In this case roots cannot easily absorb PO 4 from soil solution, as soon as the soil is quite saturated. On the other hand, it seems that P absorption occurs very quickly and easily when the implantation of 32 P tagged solution is carried out at the border of zone which is concerned by the irrigation effects [fr

Irrigation and climate information in Burkina Faso (AARC) | Page 2 ...

International Development Research Centre (IDRC) Digital Library (Canada)

Supplemental irrigation in farming systems : history of a practice and outlooks for Burkina Faso. Études. Adoption et impacts de l'irrigation de complément en zone sahélienne : modélisation bioéconomique d'une exploitation à Kongoussi. Études. Analyse comparative des modes d'exhaure et de deux techniques culturales ...

Nematode Community Composition under Various Irrigation Schemes in a Citrus Soil Ecosystem.

Science.gov (United States)

Porazinska, D L; McSorley, R; Duncan, L W; Graham, J H; Wheaton, T A; Parsons, L R

1998-06-01

Interest in the sustainability of farming practices has increased in response to environmental problems associated with conventional agricultural management often adopted for the production of herbaceous crops, ornamentals, and fruit crops. Availability of measures of the status of the soil ecosystem is of immediate importance, particularly for environmental assessment and monitoring programs. This study investigated the effects of various irrigation regimes (an example of an agricultural management practice) on the structure of the nematode fauna in a citrus orchard in the sandy ridge area of Central Florida. Ecological measures such as community structure indices, diversity indices, and maturity indices were assessed and related to irrigation intensity. Maturity index was an effective measure in distinguishing differences between irrigation regimes, whereas other indices of community structure were not. Of various nematode genera and trophic groups, only omnivores and the omnivore genera. Aporcelaimellus and Eudorylaimus responded to irrigation treatments.

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)

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

[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.

Effects of Sowing Date and Limited Irrigation on Yield and Yield Components of Five Rainfed Wheat Varieties in Maragheh Region

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A. R. Tavakkoli

2013-03-01

Full Text Available In order to investigate the effects of sowing date (SD and single irrigation (SI amounts on yield and yield components of rainfed wheat varieties, a field experiment was conducted as split-split plots arranged in a randomized complete blocks design with three replications during 2002-2004 at main station of Dryland Agricultural Research Institute in Maragheh, Iran. Treatments included three sowing dates (early, normal and late, three levels of single irrigation (rainfed, 50 mm and 100 mm only at planting time and five wheat varieties (three numbered lines, Azar2 and double-cross Shahi. Results revealed that interactions of SD, SI and wheat varieties were significant for grain yield, number of kernels per spike and water productivity (P≤0.01. Single irrigation at normal planting time increased grain yield, straw, biomass, harvest index, and water productivity. Grain yield and water productivity were increased by 131% and 84.8%, respectively. Single irrigation at late planting time was not significant on agronomic traits and produced low water productivity. Regarding the reaction of wheat to planting date and single irrigation, results showed that normal single irrigation can improve yield, yield components and water productivity index. The effectiveness of single irrigation under dryland conditions can be observed in all wheat cultivars. Although this effectiveness on yield and yield components is observable, but it is necessary to select the time of irrigation properly.

Water Leakage and Nitrate Leaching Characteristics in the Winter Wheat–Summer Maize Rotation System in the North China Plain under Different Irrigation and Fertilization Management Practices

Directory of Open Access Journals (Sweden)

Shufeng Chen

2017-02-01

Full Text Available Field experiments were carried out in Huantai County from 2006 to 2008 to evaluate the effects of different nitrogen (N fertilization and irrigation management practices on water leakage and nitrate leaching in the dominant wheat–maize rotation system in the North China Plain (NCP. Two N fertilization (NF1, the traditional one; NF2, fertilization based on soil testing and two irrigation (IR1, the traditional one; IR2, irrigation based on real-time soil water content monitoring management practices were designed in the experiments. Water and nitrate amounts leaving the soil layer at a depth of 2.0 m below the soil surface were calculated and compared. Results showed that the IR2 effectively reduced water leakage and nitrate leaching amounts in the two-year period, especially in the winter wheat season. Less than 10 percent irrigation water could be saved in a dry winter wheat season, but about 60 percent could be saved in a wet winter wheat season. Besides, 58.8 percent nitrate under single NF2IR1 and 85.2 percent under NF2IR2 could be prevented from leaching. The IR2 should be considered as the best management practice to save groundwater resources and prevent nitrate from leaching. The amounts of N input play a great role in affecting nitrate concentrations in the soil solutions in the winter wheat–summer maize rotation system. The NF2 significantly reduced N inputs and should be encouraged in ordinary agricultural production. Thus, nitrate leaching and groundwater contamination could be alleviated, but timely N supplement might be needed under high precipitation condition.

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...

Sorption behavior of nonylphenol (NP) on sewage-irrigated soil: Kinetic and thermodynamic studies

International Nuclear Information System (INIS)

Liao, Xiaoping; Zhang, Caixiang; Yao, Linlin; Li, Jiale; Liu, Min; Xu, Liang; Evalde, Mulindankaka

2014-01-01

The reuse of wastewater for irrigation of agricultural land is a well established resources management practice but has the disadvantage of inputting various forms of contaminants into the terrestrial environment including nonylphenol (NP), a well known endocrine disrupting substance. To elucidate the environmental fate and transport of NP, the sorption behavior on sewage-irrigated soil was studied by batch experiment. It was found that sorption processes of NP on different sorbents (soil, humic acid (HA) and silica) could be expressed well using two compartment pseudo first-order model, where both surface and intra-particle diffusion were probable rate-controlling processes. Linear model could better express the sorption of NP on soil, black carbon (BC) and mineral (e.g., SiO 2 ) except HA than Freundlich model. The large value of distribution coefficients of normalized organic carbon (K oc ) on soils indicated that NP was limited to migrate to deep soil. The higher desorption partition coefficient of NP on soil showed enhanced hysteresis. According to the experimental data, the calculated thermodynamic parameters implied that the sorption reaction on sewage-irrigation was spontaneous, exothermic and entropy decreasing process. The amount of soil organic matter (SOM) dominated the sorption capacity, whereas the sorption behavior of NP on soil showed no significant correlation with ionic strength. - Highlights: • Both surface and intra-particle diffusion were rate-controlling processes. • Soil composition influences the partition activity of NP. • Soil organic matter has dominated the sorption capacity of NP on soil. • NP molecule was limited to migrate to deep soil in sewage-irrigated area

Towards Global Simulation of Irrigation in a Land Surface Model: Multiple Cropping and Rice Paddy in Southeast Asia

Science.gov (United States)

Beaudoing, Hiroko Kato; Rodell, Matthew; Ozdogan, Mutlu

2010-01-01

Agricultural land use significantly influences the surface water and energy balances. Effects of irrigation on land surface states and fluxes include repartitioning of latent and sensible heat fluxes, an increase in net radiation, and an increase in soil moisture and runoff. We are working on representing irrigation practices in continental- to global-scale land surface simulation in NASA's Global Land Data Assimilation System (GLDAS). Because agricultural practices across the nations are diverse, and complex, we are attempting to capture the first-order reality of the regional practices before achieving a global implementation. This study focuses on two issues in Southeast Asia: multiple cropping and rice paddy irrigation systems. We first characterize agricultural practices in the region (i.e., crop types, growing seasons, and irrigation) using the Global data set of monthly irrigated and rainfed crop areas around the year 2000 (MIRCA2000) dataset. Rice paddy extent is identified using remote sensing products. Whether irrigated or rainfed, flooded fields need to be represented and treated explicitly. By incorporating these properties and processes into a physically based land surface model, we are able to quantify the impacts on the simulated states and fluxes.

An index-based approach for the sustainability assessment of irrigation practice based on the water-energy-food nexus framework

Science.gov (United States)

de Vito, Rossella; Portoghese, Ivan; Pagano, Alessandro; Fratino, Umberto; Vurro, Michele

2017-12-01

Increasing pressure affects water resources, especially in the agricultural sector, with cascading impacts on energy consumption. This is particularly relevant in the Mediterranean area, showing significant water scarcity problems, further exacerbated by the crucial economic role of agricultural production. Assessing the sustainability of water resource use is thus essential to preserving ecosystems and maintaining high levels of agricultural productivity. This paper proposes an integrated methodology based on the Water-Energy-Food Nexus to evaluate the multi-dimensional implications of irrigation practices. Three different indices are introduced, based on an analysis of the most influential factors. The methodology is then implemented in a catchment located in Puglia (Italy) and a comparative analysis of the three indices is presented. The results mainly highlight that economic land productivity is a key driver of irrigated agriculture, and that groundwater is highly affordable compared to surface water, thus being often dangerously perceived as freely available.

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...

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.

Colostomy irrigation: its role in improving the colostomate's quality of life.

Science.gov (United States)

Stuart, M

1976-11-20

The wider use of the irrigation technique for the management of the permanent colostomy has previously been advocated. The results of its use in a group of 10 colostomates followed more than two years is discussed. As more than half of these colostomates have been able to resume a normal life after beginning colostomy irrigation, a further plea is made for a better understanding of the technique and the advantages that it offers.

Prescribing perfection. Emergence of an engineering irrigation design approach in the Netherlands East Indies and its legacy, 1830 - 1990

NARCIS (Netherlands)

Ertsen, M.W.

2005-01-01

The apparent persistency of colonial irrigation elements in Dutch irrigation practice and education is the main source of inspiration for this book; the Netherlands East Indian irrigation regime, consisting of explicit and implicit rules for irrigation design is its subject. The book explains how

Development of High Resolution Data for Irrigated Area and Cropping Patterns in India

Science.gov (United States)

K a, A.; Mishra, V.

2015-12-01

Information of crop phenology and its individual effect on irrigation is essential to improve the simulation of land surface states and fluxes. We use moderate resolution imaging spectroradiometer (MODIS) - Normalized difference vegetation index (NDVI) at 250 m resolution for monitoring temporal changes in irrigation and cropping patterns in India. We used the obtained dataset of cropping pattern for quantifying the effect of irrigation on land surface states and fluxes by using an uncoupled land surface model. The cropping patterns are derived by using the planting, heading, harvesting, and growing dates for each agro-ecological zone separately. Moreover, we developed a high resolution irrigated area maps for the period of 1999-2014 for India. The high resolution irrigated area was compared with relatively coarse resolution (~ 10km) irrigated area from the Food and Agricultural Organization. To identify the seasonal effects we analyzed the spatial and temporal change of irrigation and cropping pattern for different temporal seasons. The new irrigation area information along with cropping pattern was used to study the water budget in India using the Noah Land surface Model (Noah LSM) for the period of 1999-2014.

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...

Reduced irrigation increases the water use efficiency and productivity of winter wheat-summer maize rotation on the North China Plain.

Science.gov (United States)

Wang, Yunqi; Zhang, Yinghua; Zhang, Rui; Li, Jinpeng; Zhang, Meng; Zhou, Shunli; Wang, Zhimin

2018-03-15

The groundwater table has fallen sharply over the last 30years on the North China Plain, resulting in a shortage of water for winter wheat irrigation. Reducing irrigation may be an important strategy to maintain agricultural sustainability in the region; however, few studies have evaluated the transition from conventional irrigation management practices to reduced irrigation management practices in the winter wheat-summer maize rotation system. Here, we compare the yield, water consumption, and water use efficiency of winter wheat-summer maize rotation under conventional irrigation and reduced irrigation on the North China Plain from 2012 to 2015. Reducing irrigation decreased the yield but increased the water use efficiency and significantly advanced the harvest date of winter wheat. As a result, the summer maize sowing date advanced significantly, and the flowering date subsequently advanced 2-8days, thus extending the summer maize grain-filling stage. Therefore, the yield and water use efficiency of summer maize were higher under reduced irrigation than conventional irrigation, which compensated for the winter wheat yield loss under reduced irrigation. In addition, under reduced irrigation from 2012 to 2015, the yield and water use efficiency advantage of the winter wheat-summer maize rotation ranged from 0.0 to 9.7% and from 4.1 to 14.7%, respectively, and water consumption and irrigated water decreased by 20-61mm and 150mm, respectively, compared to conventional irrigation. Overall, the reduced irrigation management practice involving no irrigation after sowing winter wheat, and sowing summer maize on June 7 produced the most favorable grain yield with superb water use efficiency in the winter wheat-summer maize rotation. This study indicates that reducing irrigation could be an efficient means to cope with water resource shortages while maintaining crop production sustainability on the North China Plain. Copyright © 2017. Published by Elsevier B.V.

Influence of deficit irrigation strategies on fatty acid and tocopherol concentration of almond (Prunus dulcis).

Science.gov (United States)

Zhu, Ying; Taylor, Cathy; Sommer, Karl; Wilkinson, Kerry; Wirthensohn, Michelle

2015-04-15

The effects of deficit irrigation on almond fatty acid and tocopherol levels were studied in a field trial. Mature almond trees were subjected to three levels of deficit irrigation (85%, 70% and 55% of potential crop evapotranspiration (ETo), as well as control (100% ETo) and over-irrigation (120% ETo) treatments. Two deficit irrigation strategies were employed: regulated deficit irrigation (RDI) and sustained deficit irrigation (SDI). Moderate deficit irrigation (85% RDI and 85% SDI) had no detrimental impact on almond kernel lipid content, but severe and extreme deficiencies (70% and 55%) influenced lipid content. Unsaturated fatty acid (USFA) and saturated fatty acid (SFA) contents fluctuated under these treatments, the oleic/linoleic ratio increased under moderate water deficiency, but decreased under severe and extreme water deficiency. Almond tocopherols concentration was relatively stable under deficit irrigation. The variation between years indicated climate has an effect on almond fruit development. In conclusion it is feasible to irrigate almond trees using less water than the normal requirement, without significant loss of kernel quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Municipal Treated Wastewater Irrigation: Microbiological Risk Evaluation

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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.

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

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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

The effect of irrigated rice cropping on the alkalinity of two alkaline rice soils in the Sahel

NARCIS (Netherlands)

Asten, van P.J.A.; Zelfde, van 't J.A.; Zee, van der S.E.A.T.M.; Hammecker, C.

2004-01-01

Irrigated rice cropping is practiced to reclaim alkaline-sodic soils in many parts of the world. This practice is in apparent contrast with earlier studies in the Sahel, which suggests that irrigated rice cropping may lead to the formation of alkaline-sodic soils. Soil column experiments were done

Irrigated agriculture and groundwater resources - towards an integrated vision and sustainable relationship.

Science.gov (United States)

Foster, Stephen; Garduño, Héctor

2013-01-01

Globally, irrigated agriculture is the largest abstractor, and predominant consumer, of groundwater resources, with large groundwater-dependent agro-economies now having widely evolved especially in Asia. Such use is also causing resource depletion and degradation in more arid and drought-prone regions. In addition crop cultivation practices on irrigated land exert a major influence on groundwater recharge. The interrelationship is such that cross-sector action is required to agree more sustainable land and water management policies, and this paper presents an integrated vision of the challenges in this regard. It is recognised that 'institutional arrangements' are critical to the local implementation of management policies, although the focus here is limited to the conceptual understanding needed for formulation of an integrated policy and some practical interventions required to promote more sustainable groundwater irrigation.

Online decision support based on modeling with the aim of increased irrigation efficiency

Science.gov (United States)

Dövényi-Nagy, Tamás; Bakó, Károly; Molnár, Krisztina; Rácz, Csaba; Vasvári, Gyula; Nagy, János; Dobos, Attila

2015-04-01

The significant changes in the structure of ownership and control of irrigation infrastructure in the past decades resultted in the decrease of total irrigable and irrigated area (Szilárd, 1999). In this paper, the development of a model-based online service is described whose aim is to aid reasonable irrigation practice and increase water use efficiency. In order to establish a scientific background for irrigation, an agrometeorological station network has been built up by the Agrometeorological and Agroecological Monitoring Centre. A website has been launched in order to provide direct access for local agricultural producers to both the measured weather parameters and results of model based calculations. The public site provides information for general use, registered partners get a handy model based toolkit for decision support at the plot level concerning irrigation, plant protection or frost forecast. The agrometeorological reference station network was established in the recent years by the Agrometeorological and Agroecological Monitoring Centre and is distributed to cover most of the irrigated cropland areas of Hungary. From the spatial aspect, the stations have been deployed mainly in Eastern Hungary with concentrated irrigation infrastructure. The meteorological stations' locations have been carefully chosen to represent their environment in terms of soil, climatic and topographic factors, thereby assuring relevant and up-to-date input data for the models. The measured parameters range from classic meteorological data (air temperature, relative humidity, solar irradiation, wind speed etc.) to specific data which are not available from other services in the region, such as soil temperature, soil water content in multiple depths and leaf wetness. In addition to the basic grid of reference stations, specific stations under irrigated conditions have been deployed to calibrate and validate the models. A specific modeling framework (MetAgro) has been developed

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

Science.gov (United States)

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

Marginal cost curves for water footprint reduction in irrigated agriculture: guiding a cost-effective reduction of crop water consumption to a permit or benchmark level

Directory of Open Access Journals (Sweden)

A. D. Chukalla

2017-07-01

Full Text Available Reducing the water footprint (WF of the process of growing irrigated crops is an indispensable element in water management, particularly in water-scarce areas. To achieve this, information on marginal cost curves (MCCs that rank management packages according to their cost-effectiveness to reduce the WF need to support the decision making. MCCs enable the estimation of the cost associated with a certain WF reduction target, e.g. towards a given WF permit (expressed in m3  ha−1 per season or to a certain WF benchmark (expressed in m3  t−1 of crop. This paper aims to develop MCCs for WF reduction for a range of selected cases. AquaCrop, a soil-water-balance and crop-growth model, is used to estimate the effect of different management packages on evapotranspiration and crop yield and thus the WF of crop production. A management package is defined as a specific combination of management practices: irrigation technique (furrow, sprinkler, drip or subsurface drip; irrigation strategy (full or deficit irrigation; and mulching practice (no, organic or synthetic mulching. The annual average cost for each management package is estimated as the annualized capital cost plus the annual costs of maintenance and operations (i.e. costs of water, energy and labour. Different cases are considered, including three crops (maize, tomato and potato; four types of environment (humid in UK, sub-humid in Italy, semi-arid in Spain and arid in Israel; three hydrologic years (wet, normal and dry years and three soil types (loam, silty clay loam and sandy loam. For each crop, alternative WF reduction pathways were developed, after which the most cost-effective pathway was selected to develop the MCC for WF reduction. When aiming at WF reduction one can best improve the irrigation strategy first, next the mulching practice and finally the irrigation technique. Moving from a full to deficit irrigation strategy is found to be a no-regret measure: it reduces the WF

Marginal cost curves for water footprint reduction in irrigated agriculture: guiding a cost-effective reduction of crop water consumption to a permit or benchmark level

Science.gov (United States)

Chukalla, Abebe D.; Krol, Maarten S.; Hoekstra, Arjen Y.

2017-07-01

Reducing the water footprint (WF) of the process of growing irrigated crops is an indispensable element in water management, particularly in water-scarce areas. To achieve this, information on marginal cost curves (MCCs) that rank management packages according to their cost-effectiveness to reduce the WF need to support the decision making. MCCs enable the estimation of the cost associated with a certain WF reduction target, e.g. towards a given WF permit (expressed in m3  ha-1 per season) or to a certain WF benchmark (expressed in m3  t-1 of crop). This paper aims to develop MCCs for WF reduction for a range of selected cases. AquaCrop, a soil-water-balance and crop-growth model, is used to estimate the effect of different management packages on evapotranspiration and crop yield and thus the WF of crop production. A management package is defined as a specific combination of management practices: irrigation technique (furrow, sprinkler, drip or subsurface drip); irrigation strategy (full or deficit irrigation); and mulching practice (no, organic or synthetic mulching). The annual average cost for each management package is estimated as the annualized capital cost plus the annual costs of maintenance and operations (i.e. costs of water, energy and labour). Different cases are considered, including three crops (maize, tomato and potato); four types of environment (humid in UK, sub-humid in Italy, semi-arid in Spain and arid in Israel); three hydrologic years (wet, normal and dry years) and three soil types (loam, silty clay loam and sandy loam). For each crop, alternative WF reduction pathways were developed, after which the most cost-effective pathway was selected to develop the MCC for WF reduction. When aiming at WF reduction one can best improve the irrigation strategy first, next the mulching practice and finally the irrigation technique. Moving from a full to deficit irrigation strategy is found to be a no-regret measure: it reduces the WF by reducing water

Water and nitrogen requirements of subsurface drip irrigated pomegranate

Science.gov (United States)

Surface drip irrigation is a well-developed practice for both annual and perennial crops. The use of subsurface drip is a well-established practice in many annual row crops, e.g. tomatoes, strawberries, lettuce. However, the use of subsurface drip on perennial crops has been slow to develop. With th...

Improving efficiencies of irrigation and nitrogen uptake in wheat

International Nuclear Information System (INIS)

Bazza, M.

2000-01-01

Three years of field studies and lysimeter experiments on irrigated wheat had the objective of finding ways of managing irrigation and N fertilization to minimize losses and reduce contamination of groundwater. Applied N had significant positive effects on crop-water consumptive use. The highest N losses occurred during early growth. Irrigation had little effect on N loss when it was practiced efficiently. Under the prevailing conditions, it is recommended that no N be applied to wheat at planting, in order to limit N losses by leaching caused by the high precipitation that usually occurs during early development when crop-N requirements are small. No more than 120 kg N ha -1 should be applied in total to minimize groundwater pollution and maximize N-uptake efficiency and economic returns. Also, for economic and environmental reasons, irrigation should be limited to 80% of the total requirement and to depths of 40 to 60 mm. (author)

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...

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

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

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

Effects of Changes in Irrigation Practices and Aquifer Development on Groundwater Discharge to the Jobos Bay National Estuarine Research Reserve near Salinas, Puerto Rico

Science.gov (United States)

Kuniansky, Eve L.; Rodriguez, Jose M.

2010-01-01

Since 1990, about 75 acres of black mangroves have died in the Jobos Bay National Estuarine Research Reserve near Salinas, Puerto Rico. Although many factors can contribute to the mortality of mangroves, changes in irrigation practices, rainfall, and water use resulted in as much as 25 feet of drawdown in the potentiometric surface of the aquifer in the vicinity of the reserve between 1986 and 2002. To clarify the issue, the U.S. Geological Survey, in cooperation with the Puerto Rico Department of Natural and Environmental Resources, conducted a study to ascertain how aquifer development and changes in irrigation practices have affected groundwater levels and groundwater flow to the Mar Negro area of the reserve. Changes in groundwater flow to the mangrove swamp and bay from 1986 to 2004 were estimated in this study by developing and calibrating a numerical groundwater flow model. The transient simulations indicate that prior to 1994, high irrigation return flows more than offset the effect of reduced groundwater withdrawals. In this case, the simulated discharge to the coast in the modeled area was 19 million gallons per day. From 1994 through 2004, furrow irrigation was completely replaced by micro-drip irrigation, thus eliminating return flows and the simulated average coastal discharge was 7 million gallons per day, a reduction of 63 percent. The simulated average groundwater discharge to the coastal mangrove swamps in the reserve from 1986 to 1993 was 2 million gallons per day, compared to an average simulated discharge of 0.2 million gallons per day from 1994 to 2004. The average annual rainfall for each of these periods was 38 inches. The groundwater discharge to the coastal mangrove swamps in the Jobos Bay National Estuarine Research Reserve was estimated at about 0.5 million gallons per day for 2003-2004 because of higher than average annual rainfall during these 2 years. The groundwater flow model was used to test five alternatives for increasing

Intra-Operative Surgical Irrigation of the Surgical Incision: What Does the Future Hold-Saline, Antibiotic Agents, or Antiseptic Agents?

Science.gov (United States)

Edmiston, Charles E; Leaper, David J

2016-12-01

Intra-operative surgical site irrigation (lavage) is common practice in surgical procedures in general, with all disciplines advocating some form of irrigation before incision closure. This practice, however, has been neither standardized nor is there compelling evidence that it effectively reduces the risk of surgical site infection (SSI). This narrative review addresses the laboratory and clinical evidence that is available to support the practice of irrigation of the abdominal cavity and superficial/deep incisional tissues, using specific irrigation solutions at the end of an operative procedure to reduce the microbial burden at wound closure. Review of PubMed and OVID for pertinent, scientific, and clinical publications in the English language was performed. Incision irrigation was found to afford a three-fold benefit: First, to hydrate the bed; second, to assist in allowing better examination of the area immediately before closure; and finally, by removing superficial and deep incisional contamination and lowering the bioburden, expedite the healing process. The clinical practice of intra-operative peritoneal lavage is highly variable and is dependent solely on surgeon preference. By contrast, intra-operative irrigation after device-related procedures has become a standard of care for the prophylaxis of acute peri-prosthetic infection. The clinical evidence that supports the use of antibiotic irrigation is limited and based on retrospective analysis and few acceptable randomized controlled trials. The results of laboratory and animal studies using aqueous 0.05% chlorhexidine gluconate are favorable, suggesting that further studies are justified to determine its clinical efficacy. The adoption of appropriate and standardized intra-operative irrigation practices into peri-operative care bundles, which include other evidence-based strategies (weight-based antimicrobial prophylaxis, antimicrobial sutures, maintenance of normothermia, and glycemic control), offers

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.

Human impacts on terrestrial hydrology: climate change versus pumping and irrigation

International Nuclear Information System (INIS)

Ferguson, Ian M; Maxwell, Reed M

2012-01-01

Global climate change is altering terrestrial water and energy budgets, with subsequent impacts on surface and groundwater resources; recent studies have shown that local water management practices such as groundwater pumping and irrigation similarly alter terrestrial water and energy budgets over many agricultural regions, with potential feedbacks on weather and climate. Here we use a fully-integrated hydrologic model to directly compare effects of climate change and water management on terrestrial water and energy budgets of a representative agricultural watershed in the semi-arid Southern Great Plains, USA. At local scales, we find that the impacts of pumping and irrigation on latent heat flux, potential recharge and water table depth are similar in magnitude to the impacts of changing temperature and precipitation; however, the spatial distributions of climate and management impacts are substantially different. At the basin scale, the impacts on stream discharge and groundwater storage are remarkably similar. Notably, for the watershed and scenarios studied here, the changes in groundwater storage and stream discharge in response to a 2.5 °C temperature increase are nearly equivalent to those from groundwater-fed irrigation. Our results imply that many semi-arid basins worldwide that practice groundwater pumping and irrigation may already be experiencing similar impacts on surface water and groundwater resources to a warming climate. These results demonstrate that accurate assessment of climate change impacts and development of effective adaptation and mitigation strategies must account for local water management practices. (letter)

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.

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

Economic assessment at farm level of the implementation of deficit irrigation for quinoa production in the Southern Bolivian Altiplano

Directory of Open Access Journals (Sweden)

J. Cusicanqui

2013-10-01

Full Text Available In the Southern Bolivian Altiplano recent research has suggested to introduce deficit irrigation as a strategy to boost quinoa yields and to stabilize it at 2.0 ton ha-1. In this study we carried out an economic assessment of the implementation of deficit irrigation at farm level using a hydro-economic model for simulating profit for quinoa production. As input of the model we worked with previously developed farms typology (livestock, quinoa and subsistence farms, simulated quinoa production with and without irrigation using AquaCrop model, and calculated yield response functions for four different climate scenarios (wet, normal, dry and very dry years. Results from the hydro-economic model demonstrate that maximum profit is achieved with less applied irrigated water than for maximum yield, and irrigated quinoa earned more profit than rainfed production for all farms types and climate scenarios. As expected, the benefits of irrigation under dry and very dry climate conditions were higher than those under normal and wet years, and benefits among farms types were higher for quinoa farms. In fact, profit of irrigated quinoa might be stabilized at around BOB 6500 ha-1 (about USD 920 compared with the huge differences found for rainfed conditions for all climate scenarios. Interestingly, the economic water productivity, expressed in terms of economic return for amount of applied irrigated water (BOB mm-1, reached the highest values with intermediate and low level of water availability schemes of deficit irrigation for all climate scenarios.

Manufacturing technology for practical Josephson voltage normals; Fertigungstechnologie fuer praxistaugliche Josephson-Spannungsnormale

Energy Technology Data Exchange (ETDEWEB)

Kohlmann, Johannes; Kieler, Oliver [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe 2.43 ' ' Josephson-Schaltungen' '

2016-09-15

In this contribution we present the manufacturing technology for the fabrication of integrated superconducting Josephson serial circuits for voltage normals. First we summarize some foundations for Josephson voltage normals and sketch the concept and the setup of the circuits, before we describe the manufacturing technology form modern practical Josephson voltage normals.

Estimating irrigated areas from satellite and model soil moisture data over the contiguous US

Science.gov (United States)

Zaussinger, Felix; Dorigo, Wouter; Gruber, Alexander

2017-04-01

irrigation practices. Consequently, future research should focus on the specific effects of different irrigation practices and crop types. This study is supported by the European Union's FP7 EartH2Observe "Global Earth Observation for Integrated Water Resource Assessment" project (grant agreement number 331 603608).

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

Water as an economic good in irrigated agriculture: theory and practice

NARCIS (Netherlands)

Hellegers, P.J.G.J.; Perry, C.J.

2004-01-01

This report describes the results of the Water Valuation and Pricing project, which aims to provide insight into the relevance of economics to typical problems found in irrigated agriculture. It first considers the theoretical basis for the use of economic instruments, then considers their

Soil quality improvement through conversion to sprinkler irrigation

Science.gov (United States)

Conversion from furrow to sprinkler irrigation is a recommended conservation practice for improved water use efficiency (and/or erosion control), but effects on soil quality indicators were unknown. Several soil quality indicators were therefore quantified within a northwestern U.S. Conservation Eff...

Uptake and Accumulation of Pharmaceuticals in Overhead- and Surface-Irrigated Greenhouse Lettuce.

Science.gov (United States)

Bhalsod, Gemini D; Chuang, Ya-Hui; Jeon, Sangho; Gui, Wenjun; Li, Hui; Ryser, Elliot T; Guber, Andrey K; Zhang, Wei

2018-01-31

Understanding the uptake and accumulation of pharmaceuticals in vegetables under typical irrigation practices is critical to risk assessment of crop irrigation with reclaimed water. This study investigated the pharmaceutical residues in greenhouse lettuce under overhead and soil-surface irrigations using pharmaceutical-contaminated water. Compared to soil-surface irrigation, overhead irrigation substantially increased the pharmaceutical residues in lettuce shoots. The increased residue levels persisted even after washing for trimethoprim, monensin sodium, and tylosin, indicating their strong sorption to the shoots. The postwashing concentrations in fresh shoots varied from 0.05 ± 0.04 μg/kg for sulfadiazine to 345 ± 139 μg/kg for carbamazepine. Root concentration factors ranged from 0.04 ± 0.14 for tylosin to 19.2 ± 15.7 for sulfamethoxazole. Translocation factors in surface-irrigated lettuce were low for sulfamethoxalzole, trimethoprim, monensin sodium, and tylosin (0.07-0.15), but high for caffeine (4.28 ± 3.01) and carbamazepine (8.15 ± 2.87). Carbamazepine was persistent in soil and hyperaccumulated in shoots.

Regulated deficit irrigation as a water management strategy in Vitis vinifera production

International Nuclear Information System (INIS)

Wample, R.L.; Smithyman, R.

2002-01-01

An initial six-year study in a commercial vineyard located in the Columbia River Valley of Washington State, United States of America, examined the management practices and potential benefits of regulated deficit irrigation (RDI) on Vitis vinifera cv. Sauvignon blanc. The objective of the treatments was to evaluate the effect of deficit irrigation prior to, compared with after, veraison. Each of four irrigation treatments was applied to 1.6 ha and replicated four times for a total 27.0 ha. Irrigation treatments were based on desired soil moisture levels in the top metre of the profile where most of the root system is found. Soil moisture was monitored using a neutron probe and the information was combined with calculations of evaporative demand to determine the irrigation required on a weekly basis. Vine growth, yield, fruit quality and cold hardiness were monitored throughout the study. The results indicated that RDI prior to veraison was effective in controlling shoot growth, as determined by shoot length and elongation rate, as well as pruning weights. Sixteen wine lots, each of approximately 12,000 litres, were prepared each season. Although there was some effect on berry weight, yield was not always significantly reduced. Full irrigation prior to veraison resulted in excessive shoot growth. RDI applied after veraison to vines with large canopies resulted in greater water deficit stress. Fruit quality was increased by pre-veraison RDI compared to postveraison RDI based on wines made. Regulated deficit irrigation applied at anytime resulted in better early-season lignification of canes and cold hardening of buds. There was a slight improvement in mid-winter cold hardiness of vines subjected to RDI. However, this effect was inconsistent. Studies on Cabernet Sauvignon and White Riesling are underway to confirm these results and to investigate the impact of RDI on fruit quality and winemaking practices. (author)

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,…

Analysis Of The Socioeconomic And Environmental Impacts Of Irrigated Agriculture In The Irrigated Perimeter Of Pau Dos Ferros (Rn

Directory of Open Access Journals (Sweden)

José Jobson Garcia de Almeida

2014-07-01

Full Text Available The Brazilian Government implemented irrigated perimeters to ameliorate problems of drought and poverty in the Northeast. In this sense, the objective of this work was to analyze the social, economic and environmental impacts generated by the practice of irrigated agriculture in the municipality of Pau dos Ferros-RN, resulting from the impacts caused by the activity. Obtained references on the topic, on-site visits and interviews with producers of the perimeter. It was observed the presence of negative impacts in the area, such as waste, contamination and water salinisation, compaction and soil erosion, deforestation caused by the removal of the native vegetation, high consumption of energy and public health problems.

Soil nitrate testing supports nitrogen management in irrigated annual crops

Directory of Open Access Journals (Sweden)

Patricia A. Lazicki

2016-12-01

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

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.

Effects of water-saving irrigation on emissions of greenhouse gases and prokaryotic communities in rice paddy soil.

Science.gov (United States)

Ahn, Jae-Hyung; Choi, Min-Young; Kim, Byung-Yong; Lee, Jong-Sik; Song, Jaekyeong; Kim, Gun-Yeob; Weon, Hang-Yeon

2014-08-01

The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups.

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.

The combined effect of deficit irrigation by treated wastewater and organic amendment on quinoa (Chenopodium quinoa Willd.) productivity

DEFF Research Database (Denmark)

Hirich, Abdelaziz; Choukr-Allah, Redouane; Jacobsen, Sven-Erik

2014-01-01

One of the most important factors that limits crop production is the availability of water. Deficit irrigation is the most important irrigation strategy to increase water use efficiency and crop water productivity. Organic amendment combined with deficit irrigation can be practical solution to co...

Irrigation in the Lower Durance: positive impacts of the agriculture

International Nuclear Information System (INIS)

Lacroix, M.; Blavoux, B.

1995-01-01

The water of river Durance is used to produce hydroelectricity and as stretch of water for tourism and since the thirteenth century for irrigation. The inherited situation is a well extended network of gravitation irrigation canals. This system is spendthrift of water, the water supplies are roughly 5 times the farming needs. The impact of this irrigation on the alluvial aquifer of the Lower Durance is the generalisation of the highest level of the water table in summer on the plain though the water budget has an average deficit of 550 mm. In addition, the nitrate concentration is maintained to an average of 17 mg/l in groundwater and 5 mg/l in streams by dilution. In fact, the irrigation dictates an average input of water with 25.4 mg/l of NO 3- . The natural isotopic tracing (oxygen 18) allows to say that 50 to 75% of the water of the alluvial aquifer come from irrigation. To improve the knowledge about the efficiency of irrigation, a mathematical groundwater model has been created. As a result, 53% of the water is lost while reaching the agricultural parcels, 19% is infiltrated during watering at the parcel and only 28% are used to satisfy the needs of plants. The realisation of this model has allowed to simulate the impact on groundwater of changes in irrigation practices which would lead to reduce the consummation of water. In the case of Lower Durance, the reduction of irrigation losses would have a strong impact on the quantity and quality of water in the alluvial aquifer. (J.S.). 10 refs., 9 figs., 2 tabs

Simulation of rice yield under different irrigation and nitrogen application managements by CropSyst model

Directory of Open Access Journals (Sweden)

Narjes ZARE

2015-12-01

Full Text Available The aim of this study was the calibration and validation of CropSyst model for rice in the city of Rasht. The necessary data were extracted from a field experiment which was carried out during 2005-2007 in a split-plot design. The main plots were irrigation regimes including continuous flooding irrigation and 5-day irrigation intervals. The subplots consisted of four nitrogen levels: zero N application, 45, 60 and 75 kg N ha-1. Normalized Root Mean Squared Error (nRMSE and Residual Mass Coefficient (Crm in calibration years were 9.3 % and 0.06, respectively. In validation year, nRMSE and Crm were 9.7 % and 0.11, respectively. According to other indices to assess irrigation regimes and fertilizer levels, the most suitable treatments regarding environmental aspect were 5-day irrigation regime and 45 kg N ha-1.

Therapeutic effect of intraductal irrigation of the salivary gland: A technical report

Energy Technology Data Exchange (ETDEWEB)

Lee, Chena [Dept. of Oral and Maxillofacial Radiology, Yonsei University College of Dentistry, Seoul (Korea, Republic of); Kim, Jo Eun; Huh, Kyoung Hoe; Yi, Won Jin; Lee, Sam Sun; Choi, Soon Chul [Dept. of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

2017-06-15

Obstructive and inflammatory disease often occurs in the major salivary glands, and no predictive treatment has yet been developed for this condition. The aim of this report was to introduce an intraductal irrigation procedure and to illustrate its application to practical patient cases. Two patients complaining of pain and swelling in the parotid gland during meals who underwent sialography were diagnosed as having sialodochitis with sialadenitis. Intraductal irrigation was then performed on the parotid gland on the side of the complaint. The irrigation procedure was conducted in the same manner as the sialography procedure, except that saline was used as the filling solution. Symptom severity was evaluated with a numerical rating scale (NRS) at the initial visit and a month after the irrigation. The initial NRS value of patient 1 was 10. The value decreased to 6 and then to 0 after 2 irrigation procedures. The NRS value of patient 2 regarding the symptoms involving the left parotid gland decreased from 4-5 to 1 after 4 irrigation procedures performed at 1-month intervals. Intraductal irrigation of the salivary gland may be a simple, safe, and effective treatment option for patients with obstructive and inflammatory disease of the salivary gland that is capable of resolving their symptoms.

Therapeutic effect of intraductal irrigation of the salivary gland: A technical report.

Science.gov (United States)

Lee, Chena; Kim, Jo-Eun; Huh, Kyoung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul

2017-06-01

Obstructive and inflammatory disease often occurs in the major salivary glands, and no predictive treatment has yet been developed for this condition. The aim of this report was to introduce an intraductal irrigation procedure and to illustrate its application to practical patient cases. Two patients complaining of pain and swelling in the parotid gland during meals who underwent sialography were diagnosed as having sialodochitis with sialadenitis. Intraductal irrigation was then performed on the parotid gland on the side of the complaint. The irrigation procedure was conducted in the same manner as the sialography procedure, except that saline was used as the filling solution. Symptom severity was evaluated with a numerical rating scale (NRS) at the initial visit and a month after the irrigation. The initial NRS value of patient 1 was 10. The value decreased to 6 and then to 0 after 2 irrigation procedures. The NRS value of patient 2 regarding the symptoms involving the left parotid gland decreased from 4-5 to 1 after 4 irrigation procedures performed at 1-month intervals. Intraductal irrigation of the salivary gland may be a simple, safe, and effective treatment option for patients with obstructive and inflammatory disease of the salivary gland that is capable of resolving their symptoms.

Longevity of shallow subsurface drip irrigation tubing under three tillage practices

Science.gov (United States)

Shallow Sub-Surface drip irrigation (S3DI) has drip tubing buried about 2-in below the soil surface. It is unknown how long drip tubing would be viable at this shallow soil depth using strip- or no-tillage systems. The objectives were to determine drip tube longevity, resultant crop yield, and parti...

Irrigation enhances local warming with greater nocturnal warming effects than daytime cooling effects

Science.gov (United States)

Chen, Xing; Jeong, Su-Jong

2018-02-01

To meet the growing demand for food, land is being managed to be more productive using agricultural intensification practices, such as the use of irrigation. Understanding the specific environmental impacts of irrigation is a critical part of using it as a sustainable way to provide food security. However, our knowledge of irrigation effects on climate is still limited to daytime effects. This is a critical issue to define the effects of irrigation on warming related to greenhouse gases (GHGs). This study shows that irrigation led to an increasing temperature (0.002 °C year-1) by enhancing nighttime warming (0.009 °C year-1) more than daytime cooling (-0.007 °C year-1) during the dry season from 1961-2004 over the North China Plain (NCP), which is one of largest irrigated areas in the world. By implementing irrigation processes in regional climate model simulations, the consistent warming effect of irrigation on nighttime temperatures over the NCP was shown to match observations. The intensive nocturnal warming is attributed to energy storage in the wetter soil during the daytime, which contributed to the nighttime surface warming. Our results suggest that irrigation could locally amplify the warming related to GHGs, and this effect should be taken into account in future climate change projections.

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

Drip irrigation in coffee crop under different planting densities: Growth and yield in southeastern Brazil

Directory of Open Access Journals (Sweden)

Gleice A. de Assis

2014-11-01

Full Text Available Irrigation associated to reduction on planting spaces between rows and between coffee plants has been a featured practice in coffee cultivation. The objective of the present study was to assess, over a period of five consecutive years, influence of different irrigation management regimes and planting densities on growth and bean yield of Coffea arabica L.. The treatments consisted of four irrigation regimes: climatologic water balance, irrigation when the soil water tension reached values close to 20 and 60 kPa; and a control that was not irrigated. The treatments were distributed randomly in five planting densities: 2,500, 3,333, 5,000, 10,000 and 20,000 plants ha-1. A split-plot in randomized block design was used with four replications. Irrigation promoted better growth of coffee plants and increased yield that varied in function of the plant density per area. For densities from 10,000 to 20,000 plants ha-1, regardless of the used irrigation management, mean yield increases were over 49.6% compared to the non-irrigated crop.

A global approach to estimate irrigated areas - a comparison between different data and statistics

Science.gov (United States)

Meier, Jonas; Zabel, Florian; Mauser, Wolfram

2018-02-01

Agriculture is the largest global consumer of water. Irrigated areas constitute 40 % of the total area used for agricultural production (FAO, 2014a) Information on their spatial distribution is highly relevant for regional water management and food security. Spatial information on irrigation is highly important for policy and decision makers, who are facing the transition towards more efficient sustainable agriculture. However, the mapping of irrigated areas still represents a challenge for land use classifications, and existing global data sets differ strongly in their results. The following study tests an existing irrigation map based on statistics and extends the irrigated area using ancillary data. The approach processes and analyzes multi-temporal normalized difference vegetation index (NDVI) SPOT-VGT data and agricultural suitability data - both at a spatial resolution of 30 arcsec - incrementally in a multiple decision tree. It covers the period from 1999 to 2012. The results globally show a 18 % larger irrigated area than existing approaches based on statistical data. The largest differences compared to the official national statistics are found in Asia and particularly in China and India. The additional areas are mainly identified within already known irrigated regions where irrigation is more dense than previously estimated. The validation with global and regional products shows the large divergence of existing data sets with respect to size and distribution of irrigated areas caused by spatial resolution, the considered time period and the input data and assumption made.

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

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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.

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...

Chicanery at the canal : changing practice in irrigation management in Western Mexico

NARCIS (Netherlands)

Zaag, van der P.

1992-01-01

Existing studies of irrigation systems show that technical elements influence social processes, and also, that certain social relationships may have technical implications. However, little has been said about the precise content of this interplay. A better insight seems important, as

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

Science.gov (United States)

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

2017-12-01

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

Yield response of cotton, maize, soybean, sugar beet, sunflower and wheat to deficit irrigation

International Nuclear Information System (INIS)

Kirda, C.; Kanber, R.; Tulucu, K.

1995-01-01

Results of several field experiments on deficit irrigation programmes in Turkey are discussed. Deficit irrigation of sugar beet with water stress imposed (i e.,irrigation omitted)during ripening,stage saved nearly 22 % water, yet with no significant yield decrease. An experiment, conducted in Turkey Region, the European part of Turkey,and aimed at studying water production functions of sunflower(i e,yield vs water consumption), revealed that water stress imposed at either head forming or seed filling stags influence yield the least , and 40 % savings of irrigation water supply , compared with traditional practices in the region, can be achieved without significant yield reduction. Water stress imposed at vegetative and flowering stages of maize hindered the yield most significantly. The results showed that deficit irrigation can be a feasible option under limited supply of irrigation if stress occurs during yield formation stage. A four year field experiments aiming at developing deficit irrigation strategies for soybean showed that soybean was at the most sensitive to water stress during flowering and pod filling stages, and irrigation during these stages would ensure high yields. Results of experiments on cotton showed that irrigations omitted during yield formation stage did not significantly hinder the yield. Similarly wheat give good yield response if irrigated at booting,heading and milking stages, depending on w heather conditions. In areas where rainfall at planting is limited, supplementary irrigation during this period can ensure good establishment of wheat crop. 1 tab; 9 figs; 59 refs (Author)

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

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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

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...

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...

Deficit irrigation and organic compost improve growth and yield of quinoa and pea

DEFF Research Database (Denmark)

Hirich, A.; Choukr-Allah, R.; Jacobsen, Sven-Erik

2014-01-01

Supplying organic matter under deficit irrigation conditions could be a practical solution to compensate the negative effect of water stress. For this purpose, studies in pea as a legume and quinoa as a new drought-tolerant crop were conducted in the south of Morocco between October 2011 and March...... significantly (P ≤ 0.05) increased seed yield by 18 and 11% under stress conditions and by 13 and 3% under full irrigation for quinoa and by 24 and 11% under full irrigation and by 41 and 25% under water-deficit irrigation for pea. It can be concluded that organic amendment improved significantly yield...... harvested yield was affected significantly (P seed yields (3.3 t ha-1 for quinoa and 5.6 t ha-1 for pea) were recorded under full irrigation and 10 t ha-1 of compost. Results indicated that organic amendment of 10 t ha-1 and 5 t ha-1...

The Evaluation of Groundwater Suitability for Irrigation and Changes in Agricultural Land of Garmsar basin

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Leila Bakhshandehmehr

2017-03-01

Full Text Available Introduction: In recent years, due to the reduction in surface water, utilization of groundwater has been increased to meet the growing demand of irrigation water. The quality of these water resources is continually changing, due to the geological formations, the amount of utilization, and climatic parameters. In many developing countries, the irrigation water is obtained from poor quality groundwater resources, which in turn, creates unfavorable circumstances for plant growth and reduces the agricultural yield. Providing adequate water resources for agricultural utilization is one of the most important steps needed to achieve the developmental targets of sustainable agriculture. Thus, this necessitates the assessment and evaluation of the quality of irrigation water. There are many proposed methods to determine the suitability of water for different applications, such as Piper, Wilcox, and Schoeller diagrams. Zoning of quality and suitability of irrigation water could represent the prone and critical areas to groundwater exploitation. Garmsar alluvial fan is one of the most sensitive areas in the country where traditional agriculture practices had turned into modern techniques and excessive exploitation of groundwater has caused an intensepressure on aquifers and increased water salinity. The aim of this study is to evaluate the suitability of groundwater for irrigation in a 10-year period (2002-2012 and its changes in this basin. Materials and Methods: Garmsar alluvial fan is located in the North-West of Semnan Province. Semnan is situated in the Southern hillside of the Alborz Mountains, in North of Iran. The study area includes the agricultural land on this alluvial fan and covers over 3750 hectares of this basin. In order to evaluate the quality of groundwater in this area, the electrical conductivity and sodium absorption ratio of 42 sample wells were calculated. The raster maps of these indicators were obtained using Geo

Management of irrigation frequency and nitrogen fertilization to mitigate GHG and NO emissions from drip-fertigated crops

NARCIS (Netherlands)

Abalos, D.; Sanchez-Martin, L.; Garcia-Torres, L.; Groenigen, van J.W.; Vallejo, A.

2014-01-01

Drip irrigation combined with split application of fertilizer nitrogen (N) dissolved in the irrigation water (i.e. drip fertigation) is commonly considered best management practice for water and nutrient efficiency. As a consequence, its use is becoming widespread. Some of the main factors

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

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...

Can irrigation water use be guided by market forces? Theory and practice

NARCIS (Netherlands)

Hellegers, P.J.G.J.; Perry, C.J.

2006-01-01

This paper provides insight into the relevance of market forces to typical problems found in irrigated agriculture. It first considers the theoretical basis for the use of economic instruments, such as volumetric water charges and tradable water rights, then considers their usefulness in the context

The Swedish study of Irrigation-fluid temperature in the evacuation of Chronic subdural hematoma (SIC!)

DEFF Research Database (Denmark)

Bartley, Andreas; Jakola, Asgeir S; Bartek, Jiri

2017-01-01

BACKGROUND: Chronic subdural hematoma (cSDH) is one of the most common conditions encountered in neurosurgical practice. Recurrence, observed in 5-30% of patients, is a major clinical problem. The temperature of the irrigation fluid used during evacuation of the hematoma might theoretically...... and health-related quality of life. DISCUSSION: Irrigation-fluid temperature might influence recurrence rates in the evacuation of chronic subdural hematomas. We present a study protocol for a multicenter randomized controlled trial investigating our hypothesis that irrigation fluid at body temperature...

Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations

Science.gov (United States)

Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.

2015-12-01

Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.

Trend Detection for the Extent of Irrigated Agriculture in Idaho’s Snake River Plain, 1984–2016

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Eric W. Chance

2018-01-01

Full Text Available Understanding irrigator responses to changes in water availability is critical for building strategies to support effective management of water resources. Using remote sensing data, we examine farmer responses to seasonal changes in water availability in Idaho’s Snake River Plain for the time series 1984–2016. We apply a binary threshold based on the seasonal maximum of the Normalized Difference Moisture Index (NDMI using Landsat 5–8 images to distinguish irrigated from non-irrigated lands. We find that the NDMI of irrigated lands increased over time, consistent with trends in irrigation technology adoption and increased crop productivity. By combining remote sensing data with geospatial data describing water rights for irrigation, we show that the trend in NDMI is not universal, but differs by farm size and water source. Farmers with small farms that rely on surface water are more likely than average to have a large contraction (over −25% in irrigated area over the 33-year period of record. In contrast, those with large farms and access to groundwater are more likely than average to have a large expansion (over +25% in irrigated area over the same period.

Modeling nitrate leaching and optimizing water and nitrogen management under irrigated maize in desert oases in Northwestern China.

Science.gov (United States)

Hu, Kelin; Li, Yong; Chen, Weiping; Chen, Deli; Wei, Yongping; Edis, Robert; Li, Baoguo; Huang, Yuanfang; Zhang, Yuanpei

2010-01-01

Understanding water and N transport through the soil profile is important for efficient irrigation and nutrient management to minimize nitrate leaching to the groundwater, and to promote agricultural sustainable development in desert oases. In this study, a process-based water and nitrogen management model (WNMM) was used to simulate soil water movement, nitrate transport, and crop growth (maize [Zea mays L.]) under desert oasis conditions in northwestern China. The model was calibrated and validated with a field experiment. The model simulation results showed that about 35% of total water input and 58% of the total N input were leached to <1.8 m depth under traditional management practice. Excessive irrigation and N fertilizer application, high nitrate concentration in the irrigation water, together with the sandy soil texture, resulted in large nitrate leaching. Nitrate leaching was significantly reduced under the improved management practice suggested by farm extension personnel; however, the water and nitrate inputs still far exceeded the crop requirements. More than 1700 scenarios combining various types of irrigation and fertilizer practices were simulated. Quantitative analysis was conducted to obtain the best management practices (BMPs) with simultaneous consideration of crop yield, water use efficiency, fertilizer N use efficiency, and nitrate leaching. The results indicated that the BMPs under the specific desert oasis conditions are to irrigate the maize with 600 mm of water in eight times with a single fertilizer application at a rate of 75 kg N ha(-1).

pH Control of Untreated Water for Irrigation

Science.gov (United States)

Poyen, Faruk Bin; Kundu, Palash K.; Ghosh, Apurba K.

2018-05-01

Irrigation in India still plays a pivotal role in the country's economic and employment structure. But due to unawareness and lack of technological upgradations and ill and careless agricultural practices, the yield from the fields is poor and not to its best capacity. There exists a lot of reasons and factors that brings down the crop productivity. One among them is the quality of irrigation water that is supplied to the fields. It is a common practice in India and other sub-continental countries not to access the water qualitatively before getting fed to the fields. Albeit, it does not have catastrophic effects on the productivity, but it affects the nourishment of the crops to some good extent. Water pH has a strong effect on the soil and crop, when it comes to absorption of nutrients by the plant bodies. With properly regulating the pH level of the irrigation water, it is possible to create an ambiance where the symbiotic effects between the soil and the plant can be optimized. In this paper, it is tried to regulate the pH levels of the water based on the type of soil and the optimal requirement by the crop. The work in this paper involves neutralization of acidic or alkaline water before it is being supplied to the farmlands. The process model is simulation based which gave considerably good and acceptable results.

Investigation of seed vigor and germination of canola cultivars under less irrigation in padding stage and after it.

Science.gov (United States)

Noori, S Ahmad Sadat; Khalaj, Hamideh; Rad, A Hosein Shirani; Alahdadi, Iraj; Akbari, Gh Abbas; Abadi, M Reza Labafi H

2007-09-01

The laboratory experiment was a factorial based on a Completely Randomized Design with four replications during 2005. Factors included two irrigation levels (normal irrigation (irrigation after 60 mm evaporation from class a pan) and less irrigation in padding stage and after it) and six winter cultivars (Licord, Okapi, Orient, SLMO64, Zarfam and Opera). The seeds used in this experiment produced under less irrigation (moderate drought stress) and they were three months in storage. The seed vigor was tested in laboratory experiment by three vigor tests, including Standard Germination test, cold test, Accelerated Ageing Test. Result showed that the accelerated aging test had significant differences on all of character in this study. Mean Comparing, showed canola cultivars had significant effect on Root/ Shoot ratio, abnormal seedling, hard seed, seedling fresh weight, MTG and FGP. Less irrigation levels had significant effect on total and shoot length, ratio root/shoot length and MTG.

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

The Practices and Politics of Making Policy: Irrigation Management Transfer in Mexico

NARCIS (Netherlands)

Rap, E.R.; Wester, P.

2013-01-01

This article argues that policy making is an interactive and ongoing process that transcends the spatio-temporal boundaries drawn by a linear, rational or instrumental model of policy. We construct this argument by analysing the making of the Irrigation Management Transfer (IMT) policy in Mexico in

Modernized Irrigation Technologies in West Africa

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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.

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.

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.

More crop per drop - Increasing input efficiency in sprinkler irrigated potatoes.

Science.gov (United States)

Kostka, Stan; Fang, Lisa; Ren, Haiqin; Glucksman, Robert; Gadd, Nick

2014-05-01

Water scarcity, climate change, and population growth are significant global challenges for producing sufficient food, fiber, and fuel in the 21st century. Feeding an increasingly hungry world necessitates innovative strategies and technologies to maximize crop production outputs while simultaneously increasing crop water productivity. In the 20th century, major advances in precision irrigation enabled producers to increase productivity while more efficiently applying water to crops. While pressurized irrigation systems can deliver water effectively to the soil surface, the efficiency of rootzone delivery may be compromised by intrinsic heterogeneities in soil wetting characteristics related to organic matter, biofilms, and hydrophobic coatings on soil particles and aggregates. Efficiently delivering applied irrigation water throughout the soil matrix is critical to increasing crop productivity. We propose that management of soil water access by surfactants is a viable management option to maintain or increase yields under deficit irrigation. Potato yield and tuber quality under sprinkler irrigation were evaluated under standard production practices or with the inclusion of an aqueous nonionic surfactant formulation (10 wt% alkoxylated polyols and 7% glucoethers) applied at 10L ha-1 between emergence and tuberization. Crop responses from multi-year evaluations conducted on irrigated potatoes in Idaho (USA) were compared to multi-year on farm grower evaluations in Australia and China. Surfactant treatment resulted in statistically significant increases in yield (+5%) and US No. 1 grades (+8%) while reducing culls (-10%) in trials conducted in Idaho, USA. Similar responses were observed in commercial grower evaluations conducted in Australia (+8% total yield, +18% mean tuber weight) and in China in 2011 (+8% total yield and +18% premium, -12% culls). Under diverse production conditions, a single application of the surfactant formulation improved crop water

IRRIGATION OF ORNAMENTAL PLANT NURSERY

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Eduardo de Aguiar do Couto

2013-01-01

Full Text Available Airports consume significant amounts of water which can be compared to the volume consumed by mid-size cities, thus practices aimed at reducing water consumption are important and necessar y. The objective of this study was to assess the reuse potential of sewage effluent produced at a mid-size international airport for nursery irri gation. The sewage treatment system consisted of a facultative pond followed by a constructed wetland, which were monitored during one hydrological year a nd the parameters COD, pH, solids, nitrogen, phosphorus and Escherichia coli we re analyzed. Removal efficiencies of 85% and 91% were achieved for C OD and solids, respectively. Removal efficiencies for ammonia nitrogen a nd total phosphorus were 77% and 59%, respectively. In terms of E. coli concen tration, the treated effluent met the recommendations by the World Health Organization for reuse in irrigation with the advantage of providing high levels of residual nutrient. The ornamental species Impatiens walleriana was irrigated with treated sewage effluent and plant growth characteristics were evalua ted. The experiment showed that reuse can enhance plant growth without signi ficantly affecting leaf tissue and soil characteristics. This study highlighted th e importance of simple technologies for sewage treatment especially in count ries which still do not present great investment in sanitation and proved that effluent reuse for landscape irrigation can provide great savings of water and financial resources for airport environments.

Resposta das culturas do girassol e do milho a diferentes cenários de rega deficitária Deficit irrigation as a criterion for irrigation water management with sunflower and maize crops

Directory of Open Access Journals (Sweden)

C. M. Toureiro

2007-01-01

the water use optimisation from an environmental point of view. This means that the decision criterion in irrigation management is “deficit irrigation”, rather than maximum ETc as the irrigation water amount. Some experiments with “deficit irrigation” of a sunflower crop (in 2004 irrigation season and maize (in 2005 were carried out in the Irrigation District of Divor (Alentejo, South Portugal. Crop growth and production parameters were evaluated relative to three experimental irrigation regimes: 1 irrigation opportunity and amount with soil available water equalling “optimum yield level”, this corresponding to a non restrictive water use by the crop, according to current procedure, irrigation amount corresponding to maximum ETc; 2 and 3 levels 1 and 2 of deficit irrigation, considering irrigation opportunity with soil available water respectively 10% and 30% under the “optimum yield level” and irrigation amounts 10% and 30% less than ETc between irrigation events. During the flowering periods normal irrigation for full ETc was practiced in all experiment plots. Crop yield data and the economic analysis show that a remarkable potential exists for saving water with “deficit irrigation”.

Colostomy Irrigation: Issues Most Important to Wound, Ostomy and Continence Nurses.

Science.gov (United States)

Tallman, Nancy J; Cobb, Martha D; Grant, Marcia; Wendel, Christopher S; Colwell, Janice; Ercolano, Elizabeth; Krouse, Robert

2015-01-01

The purpose of this study was to describe issues that WOC nurses find most important related to colostomy irrigation (CI). This is an additional analysis of a study focusing on qualitative responses to a survey querying WOC nurses about CI practices. The target population was members of the Wound, Ostomy and Continence Nurses Society. Of the 985 nurses who responded to the survey, 338 (34.3%) answered the optional open-ended question asking for additional comments. A 1-time online survey was conducted. In addition to demographic, educational information, and forced-choice questions about CI, an open-ended question asked for any additional comments about their experience with irrigation and WOC practice. Content analysis was used to identify common themes identified by WOC nurses. Three hundred thirty-eight out of 985 WOC nurses (34.3%) answered the optional open-ended question asking for additional comments; analysis for this study is based on these responses. WOC nurses who responded to the open-ended question had similar characteristics to those who responded to the entire survey but were significantly more experienced (15.1 vs 11.0 years; P irrigation techniques are recommended.

How Patients Experience Antral Irrigation

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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.

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

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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

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

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

shallow aquifer through canal seepage. The water flowing out of the canal system accounted for approximately 32% of the water in the CIDS canals. The storage capacity of the CIDS canals is negatively correlated to the precipitation. In years with abundant precipitation, the volume of the surface runoff and drainage from the cropland may surpass the storage capacities of the CIDS canals, while in years with less precipitation, partial storage capacity of the CIDS canal may be occupied by the diversion water from the Yellow River. Proper maintenance of the storage capacity of the CIDS has the potential in improving the efficiency of reusing the surface runoff and field drainage for irrigation practices to mitigate the increasing water shortage along the lower Yellow River.

Irrigation and fertilization effects on Nantucket Pine Tip Moth (Lepidoptera: Tortricidae) Damage levels and pupal weight in an intensively-managed pine plantation.

Energy Technology Data Exchange (ETDEWEB)

Coyle, David, R.; Nowak, John, T.; Fettig, Christopher, J.

2003-10-01

The widespread application of intensive forest management practices throughout the southeastern U.S. has increased loblolly pine, Pinus taeda L., yields and shortened conventional rotation lengths. Fluctuations in Nantucket pine tip moth, Rhyacionia frustrana (Comstock), population density and subsequent damage levels have been linked to variations in management intensity. We examined the effects of two practices, irrigation and fertilization, on R. frustrana damage levels and pupal weights in an intensively-managed P. taeda plantation in South Carolina. Trees received intensive weed control and one of the following treatments; irrigation only. fertilization only, irrigation + fertilization, or control. Mean whole-tree tip moth damage levels ranged from <1 to 48% during this study. Damage levels differed significantly among treatments in two tip moth generations in 2001, but not 2000. Pupal weight was significantly heavier in fertilization compared to the irrigation treatment in 2000, but no significant differences were observed in 2001. Tree diameter. height. and aboveground volume were significantly greater in the irrigation + fertilization than in the irrigation treatment after two growing seasons. Our data suggest that intensive management practices that include irrigation and fertilization do not consistently increase R. frustrana damage levels and pupal weights as is commonly believed. However, tip moth suppression efforts in areas adjacent to our study may have partially reduced the potential impacts of R. frustrana on this experiment.

Farmers' logics in engaging with projects promoting drip irrigation kits in Burkina Faso

OpenAIRE

Wanvoeke, J.; Venot, Jean-Philippe; Zwarteveen, M.; de Fraiture, C.

2016-01-01

Development agencies enthusiastically promote micro-drip irrigation as an affordable water and labor-saving device, yet most farmers stop using it as soon as development projects end. This article analyzes why farmers engage in projects promoting drip irrigation kits, even though they appear not to be interested in their water and labor-saving attributes. We combine practice-based theories of innovation with insights from the anthropology of development to explain that in development project ...

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.

Microbiological assessment of food crops irrigated with domestic ...

African Journals Online (AJOL)

A preliminary trial was set up in 2003 using this water to irrigate vegetables to be used for home consumption. The microbiological safety of this practice needed to be examined to ensure that it would indeed help to uplift communities by the provision of healthy food as well as provide an ecologically sound use and reuse of ...

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...

Effects of water-saving irrigation practices and drought resistant rice variety on greenhouse gas emissions from a no-till paddy in the central lowlands of China

Energy Technology Data Exchange (ETDEWEB)

Xu, Ying; Ge, Junzhu; Tian, Shaoyang; Li, Shuya [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Nguy-Robertson, Anthony L. [Center for Advanced Land Management Information Technologies, School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE 68583-0973 (United States); Zhan, Ming, E-mail: zhanming@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Cao, Cougui, E-mail: ccgui@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China)

2015-02-01

As pressure on water resources increases, alternative practices to conserve water in paddies have been developed. Few studies have simultaneously examined the effectiveness of different water regimes on conserving water, mitigating greenhouse gases (GHG), and maintaining yields in rice production. This study, which was conducted during the drought of 2013, examined all three factors using a split-plot experiment with two rice varieties in a no-till paddy managed under three different water regimes: 1) continuous flooding (CF), 2) flooded and wet intermittent irrigation (FWI), and 3) flooded and dry intermittent irrigation (FDI). The Methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions were measured using static chamber-gas measurements, and the carbon dioxide (CO{sub 2}) emissions were monitored using a soil CO{sub 2} flux system (LI-8100). Compared with CF, FWI and FDI irrigation strategies reduced CH{sub 4} emissions by 60% and 83%, respectively. In contrast, CO{sub 2} and N{sub 2}O fluxes increased by 65% and 9%, respectively, under FWI watering regime and by 104% and 11%, respectively, under FDI managed plots. Although CO{sub 2} and N{sub 2}O emissions increased, the global warming potential (GWP) and greenhouse gas intensity (GHGI) of all three GHG decreased by up to 25% and 29% (p < 0.01), respectively, using water-saving irrigation strategies. The rice variety also affected yields and GHG emissions in response to different water regimes. The drought-resistance rice variety (HY3) was observed to maintain yields, conserve water, and reduce GHG under the FWI irrigation management compared with the typical variety (FYY299) planted in the region. The FYY299 only had significantly lower GWP and GHGI when the yield was reduced under FDI water regime. In conclusion, FWI irrigation strategy could be an effective option for simultaneously saving water and mitigating GWP without reducing rice yields using drought-resistant rice varieties, such as HY3

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.

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-07-01

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

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.

Effects of shallow groundwater management on the spatial and temporal variability of boron and salinity in an irrigated field

NARCIS (Netherlands)

Shouse, P.J.; Goldberg, S.; Skaggs, T.H.; Soppe, R.W.O.; Ayars, J.E.

2006-01-01

In some irrigated regions, the disposal of agricultural drainage waters poses significant environmental challenges. Efforts are underway to develop irrigation water management practices that reduce the volume of drainage generated. One such management strategy involves restricting flow in subsurface

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 ...

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 ...

Water quality of surface runoff and lint yield in cotton under furrow irrigation in Northeast Arkansas.

Science.gov (United States)

Adviento-Borbe, M Arlene A; Barnes, Brittany D; Iseyemi, Oluwayinka; Mann, Amanda M; Reba, Michele L; Robertson, William J; Massey, Joseph H; Teague, Tina G

2018-02-01

Use of furrow irrigation in row crop production is a common practice through much of the Midsouth US and yet, nutrients can be transported off-site through surface runoff. A field study with cotton (Gossypium hirsutum, L.) was conducted to understand the impact of furrow tillage practices and nitrogen (N) fertilizer placement on characteristics of runoff water quality during the growing season. The experiment was designed as a randomized complete block design with conventional (CT) and conservation furrow tillage (FT) in combination with either urea (URN) broadcast or 32% urea ammonium nitrate (UAN) injected, each applied at 101kgNha -1 . Concentrations of ammonium (NH 4 -N), nitrate (NO 3 -N), nitrite (NO 2 -N), and dissolved phosphorus (P) in irrigation runoff water and lint yields were measured in all treatments. The intensity and chemical form of nutrient losses were primarily controlled by water runoff volume and agronomic practice. Across tillage and fertilizer N treatments, median N concentrations in the runoff were water. Water pH, specific electrical conductivity, alkalinity and hardness were within levels that common to local irrigation water and less likely to impair pollution in waterways. Lint yields averaged 1111kgha -1 and were higher (P-value=0.03) in FT compared to CT treatments. Runoff volumes across irrigation events were greater (P-value=0.02) in CT than FT treatments, which increased NO 3 -N mass loads in CT treatments (394gNO 3 -Nha -1 season -1 ). Nitrate-N concentrations in CT treatments were still low and pose little threat to N contaminations in waterways. The findings support the adoption of conservation practices for furrow tillage and N fertilizer placement that can reduce nutrient runoff losses in furrow irrigation systems. Published by Elsevier B.V.

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.

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...

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.

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...

Irrigation and drainage in agriculture: a salinity and environmental perspective

NARCIS (Netherlands)

Zee, van der S.E.A.T.M.; Stofberg, S.F.; Yang, X.; Liu, Y.; Islam, M.N.; Hu, Yin Fei

2017-01-01

Whereas irrigation and drainage are intended to address the shortage and surplus of soil water, respectively, an important aspect to address is also the management of salinity. Plants have a limited tolerance for soil water salinity, and despite significant gaps in our practical knowledge, an

Global assessment of urban and peri-urban agriculture: irrigated and rainfed croplands

Science.gov (United States)

Thebo, A. L.; Drechsel, P.; Lambin, E. F.

2014-11-01

The role of urban agriculture in global food security is a topic of increasing discussion. Existing research on urban and peri-urban agriculture consists largely of case studies that frequently use disparate definitions of urban and peri-urban agriculture depending on the local context and study objectives. This lack of consistency makes quantification of the extent of this practice at the global scale difficult. This study instead integrates global data on croplands and urban extents using spatial overlay analysis to estimate the global area of urban and peri-urban irrigated and rainfed croplands. The global area of urban irrigated croplands was estimated at about 24 Mha (11.0 percent of all irrigated croplands) with a cropping intensity of 1.48. The global area of urban rainfed croplands found was approximately 44 Mha (4.7 percent of all rainfed croplands) with a cropping intensity of 1.03. These values were derived from the MIRCA2000 Maximum Monthly Cropped Area Grids for irrigated and rainfed crops and therefore their sum does not necessarily represent the total urban cropland area when the maximum extent of irrigated and rainfed croplands occurs in different months. Further analysis of croplands within 20 km of urban extents show that 60 and 35 percent of, respectively, all irrigated and rainfed croplands fall within this distance range.

Global assessment of urban and peri-urban agriculture: irrigated and rainfed croplands

International Nuclear Information System (INIS)

Thebo, A L; Drechsel, P; Lambin, E F

2014-01-01

The role of urban agriculture in global food security is a topic of increasing discussion. Existing research on urban and peri-urban agriculture consists largely of case studies that frequently use disparate definitions of urban and peri-urban agriculture depending on the local context and study objectives. This lack of consistency makes quantification of the extent of this practice at the global scale difficult. This study instead integrates global data on croplands and urban extents using spatial overlay analysis to estimate the global area of urban and peri-urban irrigated and rainfed croplands. The global area of urban irrigated croplands was estimated at about 24 Mha (11.0 percent of all irrigated croplands) with a cropping intensity of 1.48. The global area of urban rainfed croplands found was approximately 44 Mha (4.7 percent of all rainfed croplands) with a cropping intensity of 1.03. These values were derived from the MIRCA2000 Maximum Monthly Cropped Area Grids for irrigated and rainfed crops and therefore their sum does not necessarily represent the total urban cropland area when the maximum extent of irrigated and rainfed croplands occurs in different months. Further analysis of croplands within 20 km of urban extents show that 60 and 35 percent of, respectively, all irrigated and rainfed croplands fall within this distance range. (letter)

Small Scale Irrigation within Water, Energy and Food Nexus Framework in Ethiopia.

Science.gov (United States)

Gerik, T.; Worqlul, A. W.; Yihun, D.; Bizimana, J. C.; Jeong, J.; Schmitter, P.; Srinivasan, R.; Richardson, J. W.; Clark, N.

2017-12-01

This study presents the nexus of food, energy and water framework in the context of small scale irrigation for vegetable production during the dry season in an irrigated agriculture system in Ethiopia. The study is based on detailed data collected in three sites of the Innovation Lab for Small Scale Irrigation (ILSSI) project in Ethiopia. The sites were Robit, Dangishta and Lemo and detailed field data was collected in 18 households in each site. The field data collected includes crop management (such as irrigation amount and dates, fertilizer rates, tillage practices, irrigation technologies, etc.) and agricultural production (crop yield, biomass, etc.) on tomato, onion and cabbage during the dry season. Four different water lifting technologies - namely rope with pulley and bucket, rope and washer pump, solar pump and motor pump - were used for water withdrawal from shallow groundwater wells. The Soil and Water Assessment Tool (SWAT) and Agricultural Policy Environmental eXtender (APEX) models were used in an integrated manner to assess water resource potential and develop water use efficiency of vegetables, which is a relationship between amount of water applied and vegetable yield. The water use efficiency for each vegetable crops were translated into energy requirement as pumping hours and potential irrigable areas for the water lifting technologies. This integrated approach was found useful to optimize water and energy use for sustainable food production using small scale irrigation. The holistic approach will not only provide a significant contribution to achieving food self-sufficiency, but will also be effective for optimizing agricultural input. Keyword: small scale irrigation, integrated modeling, water lifting technology, East Africa

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.

Long-term no-till and stover retention each decrease the global warming potential of irrigated continuous corn.

Science.gov (United States)

Jin, Virginia L; Schmer, Marty R; Stewart, Catherine E; Sindelar, Aaron J; Varvel, Gary E; Wienhold, Brian J

2017-07-01

Over the last 50 years, the most increase in cultivated land area globally has been due to a doubling of irrigated land. Long-term agronomic management impacts on soil organic carbon (SOC) stocks, soil greenhouse gas (GHG) emissions, and global warming potential (GWP) in irrigated systems, however, remain relatively unknown. Here, residue and tillage management effects were quantified by measuring soil nitrous oxide (N 2 O) and methane (CH 4 ) fluxes and SOC changes (ΔSOC) at a long-term, irrigated continuous corn (Zea mays L.) system in eastern Nebraska, United States. Management treatments began in 2002, and measured treatments included no or high stover removal (0 or 6.8 Mg DM ha -1  yr -1 , respectively) under no-till (NT) or conventional disk tillage (CT) with full irrigation (n = 4). Soil N 2 O and CH 4 fluxes were measured for five crop-years (2011-2015), and ΔSOC was determined on an equivalent mass basis to ~30 cm soil depth. Both area- and yield-scaled soil N 2 O emissions were greater with stover retention compared to removal and for CT compared to NT, with no interaction between stover and tillage practices. Methane comprised <1% of total emissions, with NT being CH 4 neutral and CT a CH 4 source. Surface SOC decreased with stover removal and with CT after 14 years of management. When ΔSOC, soil GHG emissions, and agronomic energy usage were used to calculate system GWP, all management systems were net GHG sources. Conservation practices (NT, stover retention) each decreased system GWP compared to conventional practices (CT, stover removal), but pairing conservation practices conferred no additional mitigation benefit. Although cropping system, management equipment/timing/history, soil type, location, weather, and the depth to which ΔSOC is measured affect the GWP outcomes of irrigated systems at large, this long-term irrigated study provides valuable empirical evidence of how management decisions can impact soil GHG emissions and surface

Multi-Dimensional Evaluation of Simulated Small-Scale Irrigation Intervention: A Case Study in Dimbasinia Watershed, Ghana

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Abeyou W. Worqlul

2018-05-01

Full Text Available This paper studied the impacts of small-scale irrigation (SSI interventions on environmental sustainability, agricultural production, and socio-economics using an Integrated Decision Support System (IDSS. The IDSS is comprised of a suite of models, namely the Soil and Water Assessment Tool (SWAT, Agricultural Policy/Environmental eXtender (APEX, and Farm Income and Nutrition Simulator (FARMSIM. The IDSS was applied in Dimbasinia watershed in northern Ghana using irrigation water from shallow groundwater. The watershed has a modest amount of shallow groundwater resources. However, the average annual irrigation water requirement exceeded the average annual shallow groundwater recharge. It was found that the current crop yield in Dimbasinia watershed was only ~40% of the potential crop production. This is mainly related to climate variability, low soil fertility, and land-management practices. For example, application of 50 kg/ha urea and 50 kg/ha DAP doubled maize and sorghum yield from the current farmers’ practices. Better income was obtained when irrigated vegetables/fodder were cultivated in rotation with sorghum as compared to in rotation with maize. Investment in solar pumps paid better dividends and also supplied clean energy. The socio-economic analysis indicated that having irrigated dry season vegetables will improve household nutrition. Since shallow groundwater recharge alone may not provide sufficient water for irrigation in a sustainable manner, surface water may be stored using water-harvesting structures to supplement the groundwater for irrigation. Integrated use of the water resources will also reduce depletion of the shallow groundwater aquifer. We conclude that IDSS is a promising tool to study gaps and constraints as well as upscaling of SSI.

Adoption of Small-Scale Irrigation Farming as a Climate-Smart Agriculture Practice and Its Influence on Household Income in the Chinyanja Triangle, Southern Africa

OpenAIRE

Nelson Mango; Clifton Makate; Lulseged Tamene; Powell Mponela; Gift Ndengu

2018-01-01

This article is concerned with the adoption of small-scale irrigation farming as a climate-smart agriculture practice and its influence on household income in the Chinyanja Triangle. Chinyanja Triangle is a region that is increasingly experiencing mid-season dry spells and an increase in occurrence of drought, which is attributed largely to climate variability and change. This poses high agricultural production risks, which aggravate poverty and food insecurity. For this region, adoption of s...

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

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kourosh majdsalimi

2016-02-01

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

Apple tree production in Italy: rootstocks, cultivars, fertilization, and irrigation

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Giovambattista Sorrenti

2012-11-01

Full Text Available Italy is one of the main apple producers in Europe, primarily intended for fresh consumption, both in the domestic and foreign markets. Fruit yield and quality depends on the cultivar, rootstock, and management practices, such as the fertilization and irrigation adopted in the orchard. This review aims at reporting the main apple cultivars and rootstocks, the management of fertilization and irrigation, as well as their adaptation to apple tree orchards in Italy. The programs for genetic improvement carried out in this country involved the selection of apple tree cultivars and rootstocks which enable a high fruit yield and quality, in order to meet the requirements from the consumer market. In the fertilization and irrigation management, nutrients and water are supplied in amounts next to the actual need of the plants, providing an adequate nutrition, a satisfactory yield, and high quality fruits, besides preventing, whenever possible, nutrients and water losses in the environment.

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.

Effect of addition of organic materials and irrigation conditions on soil quality in olive groves in the region of Messinia, Greece.

Science.gov (United States)

Kavvadias, Victor; Papadopoulou, Maria; Vavoulidou, Evangelia; Theocharopoulos, Sideris; Repas, Spiros; Koubouris, Georgos; Psaras, Georgios

2017-04-01

Intensive cultivation practices are associated to soil degradation mainly due to low soil organic matter content. The application of organic materials to land is a common practice in sustainable agriculture in the last years. However, its implementation in olive groves under different irrigation regimes has not been systematically tested under the prevailing Mediterranean conditions. The aim of this work was to study the effect of alternative carbon input techniques (i.e. wood shredded, pruning residues, returning of olive mill wastes the field with compost) and irrigation conditions (irrigated and rainfed olive orchards) on spatial distribution of soil chemical (pH, EC, total organic carbon, total nitrogen, inorganic nitrogen, humic and fulvic acids, available P, and exchangeable K) and microbial properties (soil basal microbial respiration and microbial biomass carbon) in two soil depths (0-10 cm and 10-40 cm). The study took place in the region of Messinia, South western Peloponnese, Greece during three year soil campaigns. Forty soil plots of olive groves were selected (20 rainfed and 20 irrigated) and carbon input practices were applied on the half of the irrigated and rainfed soil parcels (10 rainfed and 10 irrigated), while the remaining ones were used as controls. The results showed significant changes of chemical and biological properties of soil in olive orchards due to carbon treatments. However, these changes were depended on irrigation conditions. Microbial parameters appeared to be reliable indicators of changes in soil management. Proper management of alternative soil carbon inputs in olive orchards can positively affect soil fertility.

Remote sensing technologies applied to the irrigation water management on a golf course

Science.gov (United States)

Pedras, Celestina; Lança, Rui; Martins, Fernando; Soares, Cristina; Guerrero, Carlos; Paixão, Helena

2015-04-01

An adequate irrigation water management in a golf course is a complex task that depends upon climate (multiple microclimates) and land cover (where crops differ in morphology, physiology, plant density, sensitivity to water stress, etc.). These factors change both in time and space on a landscape. A direct measurement provides localized values of the evapotranspiration and climate conditions. Therefore this is not a practical or economical methodology for large-scale use due to spatial and temporal variability of vegetation, soils, and irrigation management strategies. Remote sensing technology combines large scale with ground measurement of vegetation indexes. These indexes are mathematical combinations of different spectral bands mostly in the visible and near infrared regions of the electromagnetic spectrum. They represent the measures of vegetation activity that vary not only with the seasonal variability of green foliage, but also across space, thus they are suitable for detecting spatial landscape variability. The spectral vegetation indexes may enhance irrigation management through the information contained in spectral reflectance data. This study was carried out on the 18th fairway of the Royal Golf Course, Vale do Lobo, Portugal, and it aims to establish the relationship between direct measurements and vegetation indexes. For that it is required (1) to characterize the soil and climatic conditions, (2) to assessment of the irrigation system, (3) to estimate the evapotranspiration (4) and to calculate the vegetation indices. The vegetation indices were determined with basis on spectral bands red, green and blue, RGB, and near Infrared, NIR, obtained from the analysis of images acquired from a unpiloted aerial vehicle, UAV, platform. The measurements of reference evapotranspiration (ETo) were obtained from two meteorological stations located in the study area. The landscape evapotranspiration, ETL, was determined in the fairway with multiple microclimates

The System Nobody Sees: Irrigated Wetland Management and Alpaca Herding in the Peruvian Andes

OpenAIRE

Verzijl, A.; Guerrero Quispe, S.

2013-01-01

Increasingly, attention in regional, national, and international water governance arenas has focused on high-altitude wetlands. However, existing local water management practices in these wetlands are often overlooked. This article looks at the irrigation activities of alpaca herders in the community of Ccarhuancho in the Central Andes of Peru. For more than two centuries, they have been constructing small-scale irrigation canals to maintain and expand the local wetlands, called bofedales. Th...

Quantifying the link between crop production and mined groundwater irrigation in China.

Science.gov (United States)

Grogan, Danielle S; Zhang, Fan; Prusevich, Alexander; Lammers, Richard B; Wisser, Dominik; Glidden, Stanley; Li, Changsheng; Frolking, Steve

2015-04-01

In response to increasing demand for food, Chinese agriculture has both expanded and intensified over the past several decades. Irrigation has played a key role in increasing crop production, and groundwater is now an important source of irrigation water. Groundwater abstraction in excess of recharge (which we use here to estimate groundwater mining) has resulted in declining groundwater levels and could eventually restrict groundwater availability. In this study we used a hydrological model, WBMplus, in conjunction with a process based crop growth model, DNDC, to evaluate Chinese agriculture's recent dependence upon mined groundwater, and to quantify mined groundwater-dependent crop production across a domain that includes variation in climate, crop choice, and management practices. This methodology allowed for the direct attribution of crop production to irrigation water from rivers and reservoirs, shallow (renewable) groundwater, and mined groundwater. Simulating 20 years of weather variability and circa year 2000 crop areas, we found that mined groundwater fulfilled 20%-49% of gross irrigation water demand, assuming all demand was met. Mined groundwater accounted for 15%-27% of national total crop production. There was high spatial variability across China in irrigation water demand and crop production derived from mined groundwater. We find that climate variability and mined groundwater demand do not operate independently; rather, years in which irrigation water demand is high due to the relatively hot and dry climate also experience limited surface water supplies and therefore have less surface water with which to meet that high irrigation water demand. Copyright © 2014 Elsevier B.V. All rights reserved.

Winter wheat grain yield and its components in the North China Plain: irrigation management, cultivation, and climate

Directory of Open Access Journals (Sweden)

Lihua Lv

2013-09-01

Full Text Available Irrigation has been identified as the main driving factor of groundwater drawdown in the North China Plain (NCP. In order to develop appropriate irrigation strategies for satisfactory yields of wheat (Triticum aestivum L., grain yield (GY, yield components, and water use efficiency (WUE were studied. A field experiment was conducted with two types of winter wheat, 'Shimai15' and 'Shixin733', and five irrigation treatments, including rainfed and four spring irrigation water applications, in four growing seasons (2005 to 2009. Results showed that maximum GY was achieved with three irrigation treatments in the 2005-2006 and 2008-2009 dry seasons and two irrigation treatments in the 2006-2007 normal season. However, in the 2007-2008 wet season, the four irrigation treatments, especially the additional irrigation event at the reviving stage (28, produced maximum GY. Grain yield was significantly related to seasonal full evapotranspiration (ET and 410 to 530 mm of seasonal full ET, including 143 mm rainfall and 214 mm irrigation water, which led to maximum GY. The two types of cultivars responded differently to irrigation management in different rainfall years. The yield of the water-saving cv. 'Shimai 15' was much higher in the dry seasons than in the other seasons. Variations of yield components were mainly caused by irrigation time and meteorological factors. The higher accumulated temperature during the sowing and tillering stages (24 and irrigation or precipitation at the reviving stage (28 significantly improved tiller growth. The lower average temperature in March and April greatly increased grain number per spike. Sunshine duration played a decisive role in improving grain weight. Our results provide very useful information about irrigation time and frequency of winter wheat in the NCP in order to obtain high yield but reduce the use of underground water.

Local Irrigation Management Institutions Mediate Changes Driven by External Policy and Market Pressures in Nepal and Thailand

Science.gov (United States)

Bastakoti, Ram C.; Shivakoti, Ganesh P.; Lebel, Louis

2010-09-01

This article assesses the role of local institutions in managing irrigation water use. Fifty irrigation systems in each country were studied in Nepal and Thailand to compare the influence of local institutions on performance of irrigation systems amid changes in external policy and market pressures. Nepal’s new irrigation policy after the re-instatement of multiparty democracy in 1990 emphasized participatory irrigation management transferring the management responsibility from state authorities to water users. The water user associations of traditional farmer-managed irrigation systems were formally recognized by requiring registration with related state authorities. In Thailand also government policies encouraged people’s participation in irrigation management. Today water users are directly involved in management of even some large irrigation systems at the level of tertiary canals. Traditional communal irrigation systems in northern Thailand received support for system infrastructure improvement but have faced increased interference from government. In Thailand market development supported diversification in farming practices resulting in increased areas under high water-demanding commercial crops in the dry season. In contrast, the command areas of most irrigation systems in Nepal include cereal-based subsistence farming with only one-third having commercial farming. Cropping intensities are higher in Nepal than in Thailand reflecting, in part, differences in availability of land and management. In both countries local institutions play an important role in maintaining the performance of irrigation systems as external drivers and local contexts change. Local institutions have provided alternative options for irrigation water use by mediating external pressures.

Irrigating The Environment

Science.gov (United States)

Adamson, D.

2017-12-01

Water insecurity and water inequality are international issues that reduce economic growth. Countries are adopting alternative approaches to rebalance the share of water between all users to mitigate economic loss for this and future generations. However, recent reforms have struggled to provide the necessary arguments to obtain political protection of the process. In the absence of proof, rent-seeking arguments have challenged the benefit of restoring environmental flows by arguing that policy design fails to maximise the environmental benefits. This is a problem in Australia's Murray-Darling Basin (MDB), where despite establishing 3,200GL of environmental water, the policy is still under threat. Applied water economic policy advice fails, when it does not deal with uncertainty. The state-contingent analysis approach can map how individual decision makers can adapt to alternative states of water supply (i.e. drought, normal and wet) by reallocating inputs to obtain state-described outputs. By modelling changes to the states, or the frequency of the states occurring, climate change can modelled, and decision management responses explored. By treating the environment as another set of production systems, lessons learnt from managing perennial and annual agricultural production systems during the Millennium Drought in the MDB can be applied to explore the limits of irrigating the environment. The demand for water by a production system is a combination of state-general (must be irrigated every year e.g. perennial crop or permanent wetland) and state specific inputs (irrigate in response to the realise state). In simple terms, the greater the component of state-general water requirements a production system has, the less resilience it has when water supply is highly variable and if water is not available then production systems are irreversibly lost. While production systems that only need state-allocable water can adapt to alternative levels of scarcity without

Global effect of irrigation and its impact on the onset of the Indian summer monsoon

Energy Technology Data Exchange (ETDEWEB)

Guimberteau, Matthieu [Universite de Paris 6, Laboratoire de Meteorologie Dynamique, Paris Cedex 05 (France); Laval, Katia [Laboratoire de Meteorologie Dynamique, Paris (France); Perrier, Alain [UFR Physique de l' Environnement, AgroParisTech, Paris (France); Polcher, Jan [CNRS, Laboratoire de Meteorologie Dynamique, Paris (France)

2012-09-15

In a context of increased demand for food and of climate change, the water consumptions associated with the agricultural practice of irrigation focuses attention. In order to analyze the global influence of irrigation on the water cycle, the land surface model ORCHIDEE is coupled to the GCM LMDZ to simulate the impact of irrigation on climate. A 30-year simulation which takes into account irrigation is compared with a simulation which does not. Differences are usually not significant on average over all land surfaces but hydrological variables are significantly affected by irrigation over some of the main irrigated river basins. Significant impacts over the Mississippi river basin are shown to be contrasted between eastern and western regions. An increase in summer precipitation is simulated over the arid western region in association with enhanced evapotranspiration whereas a decrease in precipitation occurs over the wet eastern part of the basin. Over the Indian peninsula where irrigation is high during winter and spring, a delay of 6 days is found for the mean monsoon onset date when irrigation is activated, leading to a significant decrease in precipitation during May to July. Moreover, the higher decrease occurs in June when the water requirements by crops are maximum, exacerbating water scarcity in this region. A significant cooling of the land surfaces occurs during the period of high irrigation leading to a decrease of the land-sea heat contrast in June, which delays the monsoon onset. (orig.)

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.

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.

Characterizing the Effects of Irrigation in the Middle East and North Africa Using Remotely Sensed Vegetation and Water Cycle Observations

Science.gov (United States)

Bolten, John; Ozdogan, Mutlu; Beaudoing, Hiroko; Rodell, Matthew

2012-01-01

A majority of the countries in the Middle East and North Africa (MENA) region suffer from water scarcity due in part to widespread rainfall deficits, unprecedented levels of water demand, and the inefficient use of renewable freshwater resources. Since a majority of the water withdrawal in the MENA is used for irrigation, there is a desperate need for improved understanding of irrigation practices and agricultural water use in the region. Here, satellite-derived irrigation maps and crop-type agricultural data are applied to the Land Data Assimilation System for the MENA region (MENA LDAS), designed to provide regional, gridded fields of hydrological states and fluxes relevant for water resources assessments. Within MENA-LDAS, the Catchment Land Surface Model (CLSM) simulates the location, timing, and amount of water applied through agricultural irrigation practices over the region from 2002-2012. In addition to simulating the irrigation impact on evapotranspiration, soil moisture, and runoff, we also investigate regional changes in terrestrial water storage (TWS) observed from the Gravity Recovery and Climate Experiment (GRACE) and simulated by CLSM.

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

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)

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

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.

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.

Potato yield and yield structure depending on irrigation

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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. .

Differential Impact of Passive versus Active Irrigation on Urban Forests in Semiarid Regions

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Luketich, A. M.; Papuga, S. A.; Crimmins, M.

2017-12-01

The network of trees within a city provides a variety of ecosystem services such as flood mitigation and reduced heat island effects. To maintain these `urban forests' in semiarid cities, the use of scarce water resources for irrigation is often necessary. Rainwater harvesting has been widely adopted in Tucson, AZ as a sustainable water source for trees, but the effects of passive water harvesting versus active irrigation on tree canopy productivity and microclimate is largely unquantified. We hypothesize that regardless of whether trees are passively or actively irrigated, deep soil moisture will be elevated compared to natural conditions; however, we expect that increased deep soil moisture conditions will be more frequent using active irrigation. Additionally, we hypothesize that similar to natural settings, urban trees will need access deep soil moisture for transpiration. Therefore, we expect that actively irrigated trees will have more periods of transpiration than passively irrigated trees and that this will result in elevated and sustained phenological activity. We also expect that this difference will translate to more ecosystem services for a longer portion of the year in actively irrigated urban forests. Here, we compare key ecohydrological indicators of passive and active irrigation systems at two sites in Tucson, AZ. Our measurements include soil moisture, transpiration, air temperature, soil temperature, below- and within- canopy temperatures, and canopy phenology. Our first year of results suggest there are differences in transpiration, canopy greening and microclimate between the two irrigation techniques and that the magnitude of these differences are highly seasonal. This research can help to improve understanding of the practices and function of green infrastructure in semiarid cities and inform models that attempt to aggregate the influence of these urban forests for understanding watershed management strategies.

Study of the technical performance of localized irrigation and its environmental and agroeconomic impact in the first areas of collective reconversion at the irrigated perimeter of the Tadla - Beni Moussa perimeter of the west - Morocco

Science.gov (United States)

Mouradi, Abdellah; Ait Yacine, Zehor; El Harti, Abderrazak

2018-05-01

The evaluation of the performance of the localized irrigation system involved a selected sample of farmers to reflect the diversity of the study area. The hydraulic diagnosis revealed the absence of apparent malfunctioning anomalies of the installations studied (Coefficient of Distribution Uniformity ≥ 90% with average application efficiencies and overall of 90.54 and 86.83% respectively). In terms of the combined use of surface and underground irrigation water this new technique has saved about 30% compared to conventional irrigation. The agro-economic evaluation revealed that the crops practiced have high value-added and optimize the value of irrigation water. The environmental impact has resulted in an average drawdown of the static level of groundwater of 2.59 m due mainly to the new irrigation method introduced, which limited the percolation of water to the aquifer. The drip-to-drip transition resulted in an increase in salinity relative compared to the reference situation (+ 0.59 %, or 0.01 mS / cm) but to different degrees depending on the prospecting soil horizon. The practice of fertilization remains the major and probable cause of soil salinization of aquifers. The effect of soluble salts on the soil was investigated through the risks associated with sodium, which showed that the soil permeability problem does not arise at this time (SAR ≤ 15). The residual sodium carbonate remains less than 1.25 meq / l thus not causing soil dispersion.

You Are How You Eat? Femininity, Normalization, and Veganism as an Ethical Practice of Freedom

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Megan A. Dean

2014-04-01

Full Text Available In this paper I argue that the practice of veganism is, or can be, a Foucauldian ethical practice of freedom. I begin by sketching out the problematization of alimentary practices within a normalizing patriarchal framework, which some feminists argue is dominant within contemporary North American society. Within this problematization, eating—for many women—is a way to manage the body’s appearance and bring it into conformity with feminine norms, and also an ongoing opportunity to exercise the will over unruly bodily desires. I then consider the narratives of women who claim that veganism helped them to relinquish disordered eating habits, temper the emotional and psychological turmoil that surrounded their alimentary practices, and mitigate antagonism toward their own bodies. In short, the practice of veganism appears to have reproblematized eating for these women. Thus, I suggest, veganism can be an ethical practice of freedom: it can loosen the tight grip of patriarchal normalization as constituted in and through disordered eating habits, and constitute subjects that are “a little less governed” by this form of power. I conclude by considering objections to this thesis, and in particular, the concern that veganism is linked to healthism, another worrying form of normalization.

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

Scheduling of Irrigation and Leaching Requirements

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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

Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions

Science.gov (United States)

Allende, Ana; Monaghan, James

2015-01-01

There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS) followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves) by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks. PMID:26151764

Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions

Directory of Open Access Journals (Sweden)

Ana Allende

2015-07-01

Full Text Available There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks.

Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions.

Science.gov (United States)

Allende, Ana; Monaghan, James

2015-07-03

There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS) followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves) by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks.

Biological degradation of chernozems under irrigation

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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

HEAVY METALS AND MICRONUTRIENTS IN THE SOIL AND GRAPEVINE UNDER DIFFERENT IRRIGATION STRATEGIES

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Vanessa de Souza Oliveira

2015-02-01

Full Text Available Soils under natural conditions have heavy metals in variable concentrations and there may be an increase in these elements as a result of the agricultural practices adopted. Transport of heavy metals in soil mainly occurs in forms dissolved in the soil solution or associated with solid particles, water being their main means of transport. In this context, the aim of this study was to evaluate the heavy metal and micronutrient content in the soil and in the grapevine plant and fruit under different irrigation strategies. The experiment was carried out in Petrolina, PE, Brazil. The treatments consisted of three irrigation strategies: full irrigation (FI, regulated deficit irrigation (RDI, and deficit irrigation (DI. During the period of grape maturation, soil samples were collected at the depths of 0-10, 10-20, 20-40, 40-60, and 60-80 cm. In addition, leaves were collected at the time of ripening of the bunches, and berries were collected at harvest. Thus, the heavy metal and micronutrient contents were determined in the soil, leaves, and berries. The heavy metal and micronutrient contents in the soil showed a stochastic pattern in relation to the different irrigation strategies. The different irrigation strategies did not affect the heavy metal and micronutrient contents in the vine leaves, and they were below the contents considered toxic to the plant. In contrast, the greater availability of water in the FI treatment favored a greater Cu content in the grape, which may be a risk to vines, causing instability and turbidity. Thus, adoption of deficit irrigation is recommended so as to avoid compromising the stability of tropical wines of the Brazilian Northeast.

Irrigation Analysis Based on Long-Term Weather Data

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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.

Temporal and spatial water use on irrigated and nonirrigated pasture-based dairy farms.

Science.gov (United States)

Higham, C D; Horne, D; Singh, R; Kuhn-Sherlock, B; Scarsbrook, M R

2017-08-01

Robust information for water use on pasture-based dairy farms is critical to farmers' attempts to use water more efficiently and the improved allocation of freshwater resources to dairy farmers. To quantify the water requirements of dairy farms across regions in a practicable manner, it will be necessary to develop predictive models. The objectives of this study were to compare water use on a group of irrigated and nonirrigated farms, validate existing water use models using the data measured on the group of nonirrigated farms, and modify the model so that it can be used to predict water use on irrigated dairy farms. Water use data were collected on a group of irrigated dairy farms located in the Canterbury, New Zealand, region with the largest area under irrigation. The nonirrigated farms were located in the Manawatu region. The amount of water used for irrigation was almost 52-fold greater than the amount of all other forms of water use combined. There were large differences in measured milking parlor water use, stock drinking water, and leakage rates between the irrigated and nonirrigated farms. As expected, stock drinking water was lower on irrigated dairy farms. Irrigation lowers the dry matter percentage of pasture, ensuring that the amount of water ingested from pasture remains high throughout the year, thereby reducing the demand for drinking water. Leakage rates were different between the 2 groups of farms; 47% of stock drinking water was lost as leakage on nonirrigated farms, whereas leakage on the irrigated farms equated to only 13% of stock drinking water. These differences in leakage were thought to be related to regional differences rather than differences in irrigated versus nonirrigated farms. Existing models developed to predict milking parlor, corrected stock drinking water, and total water use on nonirrigated pasture-based dairy farms in a previous related study were tested on the data measured in the present research. As expected, these models

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

Monitoring irrigation water consumption using high resolution NDVI image time series (Sentinel-2 like). Calibration and validation in the Kairouan plain (Tunisia)

Science.gov (United States)

Saadi, Sameh; Simonneaux, Vincent; Boulet, Gilles; Mougenot, Bernard; Zribi, Mehrez; Lili Chabaane, Zohra

2015-04-01

Water scarcity is one of the main factors limiting agricultural development in semi-arid areas. It is thus of major importance to design tools allowing a better management of this resource. Remote sensing has long been used for computing evapotranspiration estimates, which is an input for crop water balance monitoring. Up to now, only medium and low resolution data (e.g. MODIS) are available on regular basis to monitor cultivated areas. However, the increasing availability of high resolution high repetitivity VIS-NIR remote sensing, like the forthcoming Sentinel-2 mission to be lunched in 2015, offers unprecedented opportunity to improve this monitoring. In this study, regional crops water consumption was estimated with the SAMIR software (Satellite of Monitoring Irrigation) using the FAO-56 dual crop coefficient water balance model fed with high resolution NDVI image time series providing estimates of both the actual basal crop coefficient (Kcb) and the vegetation fraction cover. The model includes a soil water model, requiring the knowledge of soil water holding capacity, maximum rooting depth, and water inputs. As irrigations are usually not known on large areas, they are simulated based on rules reproducing the farmer practices. The main objective of this work is to assess the operationality and accuracy of SAMIR at plot and perimeter scales, when several land use types (winter cereals, summer vegetables…), irrigation and agricultural practices are intertwined in a given landscape, including complex canopies such as sparse orchards. Meteorological ground stations were used to compute the reference evapotranspiration and get the rainfall depths. Two time series of ten and fourteen high-resolution SPOT5 have been acquired for the 2008-2009 and 2012-2013 hydrological years over an irrigated area in central Tunisia. They span the various successive crop seasons. The images were radiometrically corrected, first, using the SMAC6s Algorithm, second, using invariant

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,

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

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

Newer Root Canal Irrigants in Horizon: A Review

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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.

The Probable Effect of Irrigation Solution and Time on Bond Strength to Coronal Dentin: An In Vitro Evaluation.

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Mokhtari, Fatemeh; Anvar, Ehsan; Mirshahpanah, Mostafa; Hemati, Hamidreza; Danesh Kazemi, Alireza

2017-01-01

The aim of this study was to evaluate the effect of root canal irrigants on the microtensile bond strength of 2-step self-etch adhesive to dentin. n this study 36 sound extracted human third molars were used. After grinding 3 mm of occlusal surface, teeth were randomly divided into 6 groups based on irrigation material naming normal saline, 5.25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) and also irrigation time (5 or 30 min). Next, teeth were restored with Clearfil SE bond adhesive resin system and Z250 composite. The teeth were then thermo cycled by thermo cycling machine, for 500 cycles between 5 º and 55 º C with 60 sec dwell time and 12 sec transfer time. All samples were sectioned into bucco-lingual slabs. The sections were submitted to the micro tensile testing machine at a crosshead speed of 0.5 mm/min until fracture. Data was analyzed using the one-way ANOVA test with the level of significance set at 0.05. Irrigation with normal saline, 5.25% NaOCl and 2% CHX for 5 or 30 min did not significantly change the microtensile bond strength of adhesive to dentin ( P =0.729 for time and P =0.153 for material). However the maximum and minimum microtensile bond strength was attributed to normal saline (44.13 N) and NaOCl (31.29 N) groups, respectively. Iirrigation solution and time have no influence on microtensile bond strength of two-step self-etch adhesive to coronal dentin.

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

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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

[Irrigants and intracanal medicaments in endodontics].

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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.

Sediment Transport Model for a Surface Irrigation System

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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.

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

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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.

Bayesian Belief Networks Approach for Modeling Irrigation Behavior

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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

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.

SWAT application in intensive irrigation systems: Model modification, calibration and validation

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Dechmi, Farida; Burguete, Javier; Skhiri, Ahmed

2012-11-01

SummaryThe Soil and Water Assessment Tool (SWAT) is a well established, distributed, eco-hydrologic model. However, using the study case of an agricultural intensive irrigated watershed, it was shown that all the model versions are not able to appropriately reproduce the total streamflow in such system when the irrigation source is outside the watershed. The objective of this study was to modify the SWAT2005 version for correctly simulating the main hydrological processes. Crop yield, total streamflow, total suspended sediment (TSS) losses and phosphorus load calibration and validation were performed using field survey information and water quantity and quality data recorded during 2008 and 2009 years in Del Reguero irrigated watershed in Spain. The goodness of the calibration and validation results was assessed using five statistical measures, including the Nash-Sutcliffe efficiency (NSE). Results indicated that the average annual crop yield and actual evapotranspiration estimations were quite satisfactory. On a monthly basis, the values of NSE were 0.90 (calibration) and 0.80 (validation) indicating that the modified model could reproduce accurately the observed streamflow. The TSS losses were also satisfactorily estimated (NSE = 0.72 and 0.52 for the calibration and validation steps). The monthly temporal patterns and all the statistical parameters indicated that the modified SWAT-IRRIG model adequately predicted the total phosphorus (TP) loading. Therefore, the model could be used to assess the impacts of different best management practices on nonpoint phosphorus losses in irrigated systems.

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

Irrigation as an Historical Climate Forcing

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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

Impacts of Irrigation and Climate Change on Water Security: Using Stakeholder Engagement to Inform a Process-based Crop Model

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Leonard, A.; Flores, A. N.; Han, B.; Som Castellano, R.; Steimke, A.

2016-12-01

Irrigation is an essential component for agricultural production in arid and semi-arid regions, accounting for a majority of global freshwater withdrawals used for human consumption. Since climate change affects both the spatiotemporal demand and availability of water in irrigated areas, agricultural productivity and water efficiency depend critically on how producers adapt and respond to climate change. It is necessary, therefore, to understand the coevolution and feedbacks between humans and agricultural systems. Integration of social and hydrologic processes can be achieved by active engagement with local stakeholders and applying their expertise to models of coupled human-environment systems. Here, we use a process based crop simulation model (EPIC) informed by stakeholder engagement to determine how both farm management and climate change influence regional agricultural water use and production in the Lower Boise River Basin (LBRB) of southwest Idaho. Specifically, we investigate how a shift from flood to sprinkler fed irrigation would impact a watershed's overall agricultural water use under RCP 4.5 and RCP 8.5 climate scenarios. The LBRB comprises about 3500 km2, of which 20% is dedicated to irrigated crops and another 40% to grass/pasture grazing land. Via interviews of stakeholders in the LBRB, we have determined that approximately 70% of irrigated lands in the region are flood irrigated. We model four common crops produced in the LBRB (alfalfa, corn, winter wheat, and sugarbeets) to investigate both hydrologic and agricultural impacts of irrigation and climatic drivers. Factors influencing farmers' decision to switch from flood to sprinkler irrigation include potential economic benefits, external financial incentives, and providing a buffer against future water shortages. These two irrigation practices are associated with significantly different surface water and energy budgets, and large-scale shifts in practice could substantially impact regional

Effect of tranexamic acid irrigation on perioperative blood loss during orthognathic surgery: a double-blind, randomized controlled clinical trial.

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Eftekharian, Hamidreza; Vahedi, Ruhollah; Karagah, Tuba; Tabrizi, Reza

2015-01-01

Perioperative hemorrhage is an important concern during orthognathic surgery. The purpose of this study was to assess the effect of tranexamic acid (TXA) irrigation on perioperative hemorrhage during orthognathic surgery. In this double-blind, randomized controlled clinical trial, 56 participants who underwent orthognathic surgery were divided into 2 groups. The patients in the first group received TXA irrigation with normal saline (1 mg/mL), and the patients in the second group had normal saline for irrigation during orthognathic surgery. Age, gender, operation duration, the amount of irrigation solution used, and preoperative hemoglobin, hematocrit, and weight were the variables that were studied. The use of TXA solution for irrigation was the predictive factor of the study. Each group consisted of 28 patients. Group 1 consisted of 15 male patients (53.6%) and 13 female patients (46.4%) and group 2 consisted of 14 male patients (50%) and 14 female patients (50%). There was no difference in the distributions of the variables between the 2 groups, except for the duration of the operation. The mean duration of the operation was 3.94 ± 0.61 hours in group 1 and 4.17 ± 0.98 hours in group 2, and the difference in this respect between the 2 groups was statistically significant (P .05). TXA is effective in reducing intraoperative blood loss in patients for whom substantial blood loss is anticipated. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Colostomy irrigation: are we offering it enough?

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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.

A scintigraphic study of colostomy irrigation

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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).

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)

Changes of soil organic matter and microbial activity in irrigated and non irrigated olive groves

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Kavvadias, Victor; Papadopoulou, Maria; Theocharopoulos, Sideris; Vavoulidou, Evagelia; Doula, Maria; Reppas, Spiros

2014-05-01

The implementation of olive cultivation techniques in Greece has not been systematically tested under the prevailing Mediterranean conditions. A LIFE+ project was initiated (oLIVE-CLIMA; LIFE 11/ENV/000942) aiming to introduce new management practices in olive tree crops that lead to increased carbon dioxide uptake by plants as well as carbon sequestration from the atmosphere and reverse the trend of soil organic matter decline, erosion and desertification. This paper presents data on soil organic matter and microbial activity from a soil campaign in a pilot region in Greece, and particularly in the area of Chora, prefecture of Messinia, South west Peloponnese. The soil campaign took place during the period December 2012-February 2013. Twelve soil parcels of olive groves were selected (6 irrigated and 6 rainfed) and in each soil parcel six composite soil samples were taken from 0-10 cm depth at equal intervals along a straight line of the trunk of the tree to the middle of the distance from the nearest tree of the next tree series. The first three samples were under olive tree canopy. An additional composite sample was taken at depth of 10-40 cm. Soil samples were analyzed for soil physicochemical and biological properties. In this study results for total organic carbon (TOC), soil basal microbial respiration (BR), microbial biomass C (MB-C) from the region of Messinia, are presented. Organic matter was determined by dichromate oxidation. The microbial activity was measured by the amount of CO2 evolution, while microbial biomass C was determined by substrate-induced respiration, after the addition of glucose. The results showed considerable differences in TOC, BR and MB-C associated with the sampling position and soil depth. The higher TOC, BR and MB-C values, in most cases, were determined in samples taken from points under the canopy, but not close to the tree trunk compared to the sampling points outside the canopy. This indicates the positive effect of

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

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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.

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...

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

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

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

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

2017-12-01

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

Development of a cost-effectiveness analysis of leafy green marketing agreement irrigation water provisions.

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Jensen, Helen H; Pouliot, Sébastien; Wang, Tong; Jay-Russell, Michele T

2014-06-01

An analysis of the effectiveness of meeting the irrigation water provisions of the Leafy Green Marketing Agreement (LGMA) relative to its costs provides an approach to evaluating the cost-effectiveness of good agricultural practices that uses available data. A case example for lettuce is used to evaluate data requirements and provide a methodological example to determine the cost-effectiveness of the LGMA water quality provision. Both cost and field data on pathogen or indicator bacterial levels are difficult and expensive to obtain prospectively. Therefore, methods to use existing field and experimental data are required. Based on data from current literature and experimental studies, we calculate a cost-efficiency ratio that expresses the reduction in E. coli concentration per dollar expenditure on testing of irrigation water. With appropriate data, the same type of analysis can be extended to soil amendments and other practices and to evaluation of public benefits of practices used in production. Careful use of existing and experimental data can lead to evaluation of an expanded set of practices.

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

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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.

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

Since receiving jurisdiction from the State Legislature in June 2003 to implement the Georgia Agricultural Water Conservation and Metering Program, the Georgia Soil and Water Conservation Commission (Commission) by year-end 2010 installed more than 10,000 annually read water meters and nearly 200 daily reporting, satellite-transmitted, telemetry sites on irrigation systems located primarily in southern Georgia. More than 3,000 annually reported meters and 50 telemetry sites were installed during 2010 alone. The Commission monitored rates and volumes of agricultural irrigation supplied by groundwater, surface-water, and well-to-pond sources to inform water managers on the patterns and amounts of such water use and to determine effective and efficient resource utilization. Summary analyses of 4 complete years of irrigation data collected from annually read water meters in the middle and lower Chattahoochee and Flint River basins during 2007-2010 indicated that groundwater-supplied fields received slightly more irrigation depth per acre than surface-water-supplied fields. Year 2007 yielded the largest disparity between irrigation depth supplied by groundwater and surface-water sources as farmers responded to severe-to-exceptional drought conditions with increased irrigation. Groundwater sources (wells and well-to-pond systems) outnumbered surface-water sources by a factor of five; each groundwater source applied a third more irrigation volume than surface water; and, total irrigation volume from groundwater exceeded that of surface water by a factor of 6.7. Metered irrigation volume indicated a pattern of low-to-high water use from northwest to southeast that could point to relations between agricultural water use, water-resource potential and availability, soil type, and crop patterns. Normalizing metered irrigation-volume data by factoring out irrigated acres allowed irrigation water use to be expressed as an irrigation depth and nearly eliminated the disparity

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...

Reduced Nitrous Oxide Emissions in Tomato Cropping Systems under Drip Irrigation and Fertigation

Science.gov (United States)

Kennedy, T.; Suddick, E. C.; Six, J. W.

2011-12-01

In California, agriculture and forestry account for 8% of the total greenhouse gas (GHG) emissions, of which 50% is accounted for by nitrous oxide (N2O). Furrow irrigation and high temperatures in the Central Valley, together with conventional fertilization, are ideal for the production of food, but also N2O. These conditions lead to high N2O fluxes, but also mean there is great potential to reduce N2O emissions by optimizing fertilizer use and irrigation practices. Improving fertilizer use by better synchronizing nitrogen (N) availability and crop demand can reduce N losses and fertilizer costs. Smaller, more frequent fertilizer applications can increase the synchrony between available soil N and crop N uptake. Fertigation allows for more control over how much N is being added and can therefore allow for better synchrony throughout the growing season. In our study, we determined how management practices, such as fertilization, irrigation, tillage and harvest, affect direct N2O emissions in typical tomato cropping systems. We evaluated two contrasting irrigation managements and their associated fertilizer application method, i.e. furrow irrigation and knife injection versus drip irrigation and fertigation. Across two tomato-growing seasons, we found that shifts in fertilizer and irrigation water management directly affect GHG emissions. Seasonal N2O fluxes were 3.4 times lower under drip versus furrow irrigation. In 2010, estimated losses of fertilizer N as N2O were 0.60 ± 0.06 kg N2O-N ha-1 yr-1 in the drip system versus 2.06 ± 0.11 N2O-N kg ha-1 yr-1 in the furrow system, which was equivalent to 0.29% and 0.87% of the added fertilizer, respectively. Carbon dioxide (CO2) emissions were also lower in the drip system (2.21 ± 0.16 Mg CO2-C ha-1 yr-1) than the furrow system (4.65 ± 0.23 Mg CO2-C ha-1 yr-1). Soil mineral N, dissolved organic carbon and soil moisture also varied between the two systems and correlated positively with N2O and CO2 emissions, depending

Malaria transmission risk variations derived from different agricultural practices in an irrigated area of northern Tanzania.

Science.gov (United States)

Ijumba, J N; Mosha, F W; Lindsay, S W

2002-03-01

Malaria vector Anopheles and other mosquitoes (Diptera: Culicidae) were monitored for 12 months during 1994-95 in villages of Lower Moshi irrigation area (37 degrees 20' E, 3 degrees 21' S; approximately 700 m a.s.l.) south of Mount Kilimanjaro in northern Tanzania. Adult mosquito populations were sampled fortnightly by five methods: human bait collection indoors (18.00-06.00 hours) and outdoors (18.00-24.00 hours); from daytime resting-sites indoors and outdoors; by CDC light-traps over sleepers. Anopheles densities and rates of survival, anthropophily and malaria infection were compared between three villages representing different agro-ecosystems: irrigated sugarcane plantation; smallholder rice irrigation scheme, and savannah with subsistence crops. Respective study villages were Mvuleni (population 2200), Chekereni (population 3200) and Kisangasangeni (population approximately/= 1000), at least 7 km apart. Anopheles arabiensis Patton was found to be the principal malaria vector throughout the study area, with An. funestus Giles sensu lato of secondary importance in the sugarcane and savannah villages. Irrigated sugarcane cultivation resulted in water pooling, but this did not produce more vectors. Anopheles arabiensis densities averaged four-fold higher in the ricefield village, although their human blood-index was significantly less (48%) than in the sugarcane (68%) or savannah (66%) villages, despite similar proportions of humans and cows (ratio 1:1.1-1.4) as the main hosts at all sites. Parous rates, duration of the gonotrophic cycle and survival rates of An. arabiensis were similar in villages of all three agro-ecosystems. The potential risk of malaria, based on measurements of vectorial capacity of An. arabiensis and An.funestus combined, was four-fold higher in the ricefield village than in the sugarcane or savannah villages nearby. However, the more realistic estimate of malaria risk, based on entomological inoculation rates, indicated that exposure to

Addressing water scarcity through limited irrigation cropping: Field experiments and modeling

Science.gov (United States)

Population growth in urbanizing areas such as the Front Range of Colorado has led to increased pressure to transfer water from agriculture to municipalities. In many cases this has led to complete dry up of productive irrigated lands. An option to complete dry-up is the practice of limited or defi...

An Interactive Real-time Decision Support System for Leachate Irrigation on Evapotranspiration Landfill Covers

Science.gov (United States)

Wang, Y.

2015-12-01

Landfill disposal is still the most common and economical practice for municipal solid waste in most countries. However, heavily polluted leachate generated by excess rainwater percolating through the landfill waste is the major drawback of this practice. Evapotranspiration (ET) cover systems are increasingly being used as alternative cover systems to minimize percolation by evapotranspiration. Leachate recirculation is one of the least expensive options for leachate treatment. The combination of ET cover systems and leachate recirculation can be an economical and environment-friendly practice for landfill leachate management. An interactive real-time decision support system is being developed to better manage leachate irrigation using historical and forecasting weather data, and real time soil moisture data. The main frame of this system includes soil water modules, and plant-soil modules. An inverse simulation module is also included to calibrate certain parameters based on observed data when necessary. It would be an objectives-oriented irrigation management tool to minimize landfill operation costs and negative environmental impacts.

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

Directory of Open Access Journals (Sweden)

Kamel Nagaz

2017-06-01

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

Irrigation management in Mediterranean salt affected agriculture: how leaching operates

Directory of Open Access Journals (Sweden)

Angela Libutti

2012-03-01

Full Text Available In the frame of a crop rotation currently applied in a farm of the Apulian Tavoliere (Southern Italy, this paper reports the effect of brackish water irrigation on soil, outlines the corresponding salinity balance, formulates quantitative relations to model salt outflow below the soil root-layer and defines operational criteria to optimize irrigation management at farm level in order to control soil salinity through leaching. The general aim is to contribute to a sustainable use of the available water resources and a proper soil fertility conservation. A three-year trial (2007-2010 was carried out on a farm located close to the coast of the Manfredonia gulf (Mediterranean - Adriatic sea, where irrigation with brackish water is frequently practiced due to seawater intrusion into the groundwater. An especially designed experimental field-unit was set-up: the bottom of three hydraulically insulated plots was covered with a plastic sheet to intercept the percolating water and collect it into tanks by means of drain tubes. Each year a double crop cycle was applied to the soil; a spring-summer crop (tomato, zucchini and pepper, respectively was followed by a fall-winter crop (spinach, broccoli and wheat. Short “fallow” periods (completely bare soil were inserted between two crop cycles. Irrigation or rain completely restored crop water consumptions (with the exception of wheat, considered a rainfed crop and leaching was performed both unintentionally (by rainfalls or intentionally (supplying higher irrigation volumes whenever the soil electrical conductivity exceeded a fixed threshold. The soil electrical conductivity was periodically measured together with volume and electrical conductivity of irrigation and drainage water. All these measures allowed to draw-up the salt-balance of the soil, respectively at the beginning and the end of each crop cycle. Absolute and relative variations in soil salt content were interpreted with respect to absolute

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 ...

Application of DSSAT-CROPGRO-Cotton Model to Assess Long Term (1924-2012) Cotton Yield under Different Irrigation Management Strategies

Science.gov (United States)

Adhikari, P.; Gowda, P. H.; Northup, B. K.; Rocateli, A.

2017-12-01

In this study a well calibrated and validated DSSAT-CROPGRO-Cotton model was used for assessing the irrigation management in the Texas High Plains (THP). Long term (1924-2012) historic lint yield were simulated under different irrigation management practices which were commonly used in the THP. The simulation treatments includes different amount of irrigation water high (H; 6.4 mm d-1), medium (M; 3.2 mm d-1) and low (L; 0 mm d-1) during emergence (S1), vegetative (S2) and maturity (S3) stage. The combination of these treatments resulted into 27 treatments. The amount and date of irrigation for each stage were obtained from the recent cotton irrigation experiment at Halfway, TX (Brodovsky, et al., 2015). Similarly, calibrated model was also used to observe the effect of plantation date on crop yield in the THP regions.

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.

Operation and monitoring guidelines and the development of a screening tool for irrigating with coal mine water in Mpumalanga Province, South Africa

Energy Technology Data Exchange (ETDEWEB)

Vermeulen, D.; Usher, B. [University of Free State, Bloemfontein (South Africa). Institute of Groundwater Studies

2009-07-15

It is predicted that vast volumes of impacted mine water will be produced by mining activities in the Mpumalanga coalfields of South Africa. The potential environmental impact of this excess water is of great concern in a water-scarce country like South Africa. Detailed research has been undertaken over the past number of years onl both undisturbed soils and in coal-mining spoils. These sites range from sandy soils to very clayey soils. The results indicate that many of the soils have considerable attenuation capacities and that over the period of irrigation, a large proportion of the salts are contained in the upper portions of the unsaturated zones below each irrigation pivot. The volumes and quality of water leaching through to the aquifers have been quantified at each site. From these data mixing ratios were calculated in order to determine the effect of the irrigation water on the underlying aquifers. One of the outcomes from this study was to define the conditions under which mine-water irrigation can be implemented and the associated operational and monitoring guidelines that should be followed. These have been based on the findings from this study, the fundamental considerations of mine-water irrigation, the regulatory environment and, as far as possible, the practical implementation of mine-water irrigation as part of optimal mine-water management. In an attempt to standardise decision-making regarding mine-water irrigation, the criteria, data, rules and fundamentals discussed have been combined in a user-friendly tool, called GIMI (Groundwater Impacts from Minewater Irrigation). This tool should assist in the practical implementation of mine-water irrigation as part of optimal mine-water management.

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...

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.

Treated wastewater irrigation effects on soil hydraulic conductivity and aggregate stability of loamy soils in Israel

Directory of Open Access Journals (Sweden)

Schacht Karsten

2015-03-01

Full Text Available The use of treated wastewater (TWW for agricultural irrigation becomes increasingly important in water stressed regions like the Middle East for substituting fresh water (FW resources. Due to elevated salt concentrations and organic compounds in TWW this practice has potential adverse effects on soil quality, such as the reduction of hydraulic conductivity (HC and soil aggregate stability (SAS. To assess the impact of TWW irrigation in comparison to FW irrigation on HC, in-situ infiltration measurements using mini disk infiltrometer were deployed in four different long-term experimental orchard test sites in Israel. Topsoil samples (0-10 cm were collected for analyzing SAS and determination of selected soil chemical and physical characteristics.

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.

Sensor-Based Assessment of Soil Salinity during the First Years of Transition from Flood to Sprinkler Irrigation

Directory of Open Access Journals (Sweden)

Mª Auxiliadora Casterad

2018-02-01

Full Text Available A key issue for agriculture in irrigated arid lands is the control of soil salinity, and this is one of the goals for irrigated districts when changing from flood to sprinkling irrigation. We combined soil sampling, proximal electromagnetic induction, and satellite data to appraise how soil salinity and its distribution along a previously flood-irrigated field evolved after its transformation to sprinkling. We also show that the relationship between NDVI (normalized difference vegetation index and ECe (electrical conductivity of the soil saturation extracts mimics the production function between yield and soil salinity. Under sprinkling, the field had a double crop of barley and then sunflower in 2009 and 2011. In both years, about 50% of the soil of the entire studied field—45 ha—had ECe < 8 dS m−1, i.e., allowing barley cultivation, while the percent of surface having ECe ≥ 16 dS m−1 increased from 8.4% in 2009 to 13.7% in 2011. Our methodology may help monitor the soil salinity oscillations associated with irrigation management. After quantifying and mapping the soil salinity in 2009 and 2011, we show that barley was stunted in places of the field where salinity was higher. Additionally, the areas of salinity persisted after the subsequent alfalfa cropping in 2013. Application of differential doses of water to the saline patches is a viable method to optimize irrigation water distribution and lessen soil salinity in sprinkler-irrigated agriculture.

Testing an Irrigation Decision Support Tool for California Specialty Crops

Science.gov (United States)

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

2015-12-01

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

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

Water quality of surface runoff and lint yield in cotton under furrow irrigation in Northeast Arkansas

Science.gov (United States)

Use of furrow irrigation in row crop production is a common practice through much of the Midsouth US and yet, nutrients can be transported off-site through surface runoff. A field study with cotton (Gossypium hirsutum, L.) was conducted to understand the impact of furrow tillage practices and nitrog...

Modified Streamflows 1990 Level of Irrigation : Columbia River and Coastal Basins, 1928-1989.

Energy Technology Data Exchange (ETDEWEB)

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

1993-04-01

The annual operation plans described in the following sections require detailed system regulation computer model studies. These system regulation studies are necessary to evaluate potential new projects and to develop operational rule curves for the existing system of projects. The objective is to provide a basis for evaluating alternative system regulation scenarios. This provides essential input for optimizing the management of existing projects and planning future projects for the most beneficial use of the water supply and resources in the entire region. Historical streamflows per se are inadequate for system regulation studies because the pattern of observed flow has continually changed with each successive stage of irrigation and e development. The problem, therefore, is to adjust for past operation of storage projects and to determine the necessary adjustments that should be made to recorded flows to reflect current stages of irrigation development. Historical flows which have been adjusted to a common level of irrigation development by correcting for the effects of diversion demand, return flow, and change-of-contents and evaporation in upstream reservoirs and lakes are referred to as modified flows. This report describes the development of irrigation depletion adjustments and modified flows for the 1990 level of development for the 61-year period 1928--1989. incremental depletion adjustments were computed in this report for each month of the 61-year period to adjust the effects of actual irrigation in each year up to that which would have been experienced with the irrigation as practiced in 1990.

Alternate furrow irrigation of four fresh-market tomato cultivars under semi-arid condition of Ethiopia – Part II: Physiological response

Directory of Open Access Journals (Sweden)

Ashinie Bogale

2016-11-01

Full Text Available Understanding the variation in physiological response to deficit irrigation together with better knowledge on physiological characteristics of different genotypes that contribute to drought adaptation mechanisms would be helpful in transferring different irrigation technologies to farmers. A field experiment was carried to investigate the physiological response of four tomato cultivars (Fetan, Chali, Cochoro and ARP Tomato d2 to moderate water deficit induced by alternate furrow irrigation (AFI and deficit irrigation (DI under semi-arid condition of Ethiopia during 2013 and 2014. The study also aimed at identifying physiological attributes to the fruit yield of tomato under different deficit irrigation techniques. A factorial combination of irrigation treatments and cultivar were arranged in a complete randomized design with three replicates. Results showed that stomatal conductance (g_s was significantly reduced while photosynthetic performance measured as chlorophyll fluorescence (Fv’/Fm’, relative water content (RWC and leaf ash content remained unaffected under deficit irrigations. Significant differences among cultivars were found for water use efficiency (WUE, g_s, chlorophyll content (Chl_SPAD, normal difference vegetation index (NDVI, leaf ash content and fruit growth rate. However, cultivar differences in WUE were more accounted for by the regulation of g_s, therefore, g_s could be useful for breeders for screening large numbers of genotypes with higher WUE under deficit irrigation condition. The study result also demonstrated that cultivar with traits that contribute to achieve higher yields under deficit irrigation strategies has the potential to increase WUE.

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...

Evaluation some Forage Legumes in Limited Irrigation Condition

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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

Cokriging of Electromagnetic Induction Soil Electrical Conductivity Measurements and Soil Textural Properties to Demarcate Sub-field Management Zones for Precision Irrigation.

Science.gov (United States)

Ding, R.; Cruz, L.; Whitney, J.; Telenko, D.; Oware, E. K.

2017-12-01

There is the growing need for the development of efficient irrigation management practices due to increasing irrigation water scarcity as a result of growing population and changing climate. Soil texture primarily controls the water-holding capacity of soils, which determines the amount of irrigation water that will be available to the plant. However, while there are significant variabilities in the textural properties of the soil across a field, conventional irrigation practices ignore the underlying variability in the soil properties, resulting in over- or under-irrigation. Over-irrigation leaches plant nutrients beyond the root-zone leading to fertilizer, energy, and water wastages with dire environmental consequences. Under-irrigation, in contrast, causes water stress of the plant, thereby reducing plant quality and yield. The goal of this project is to leverage soil textural map of a field to create water management zones (MZs) to guide site-specific precision irrigation. There is increasing application of electromagnetic induction methods to rapidly and inexpensively map spatially continuous soil properties in terms of the apparent electrical conductivity (ECa) of the soil. ECa is a measure of the bulk soil properties, including soil texture, moisture, salinity, and cation exchange capacity, making an ECa map a pseudo-soil map. Data for the project were collected from a farm site at Eden, NY. The objective is to leverage high-resolution ECa map to predict spatially dense soil textural properties from limited measurements of soil texture. Thus, after performing ECa mapping, we conducted particle-size analysis of soil samples to determine the textural properties of soils at selected locations across the field. We cokriged the high-resolution ECa measurements with the sparse soil textural data to estimate a soil texture map for the field. We conducted irrigation experiments at selected locations to calibrate representative water-holding capacities of each

Effect of Different Irrigation Solutions on the Colour Stability of Three Calcium Silicate-Based Materials

Directory of Open Access Journals (Sweden)

Sobhnamayan F

2017-06-01

Full Text Available Abstract: Statement of Problem: Previous studies have shown discoloration of mineral trioxide aggregate (MTA in contact with root canal irrigation solutions. However, there are limited data on colour stability of other calcium silicate–based materials (CSMs. Objectives: This in vitro study aimed to evaluate the colour stability of three CSMs in contact with different irrigation solutions. Materials and Methods: Three CSMs including White MTA (wMTA Angelus, calcium enriched mixture (CEM, and Biodentine were assessed in this study. Forty five samples of each material were mixed according to the manufactures’ instructions and then placed in silicone tubes. After 24 hours, the materials were removed from the moulds and 9 samples of each material left dry or immersed in normal saline, 5% sodium hypochlorite (NaOCL, 2% chlorhexidinegluconate (CHX, or 17%EDTA for 24 hours. Colour changes were measured with a spectrophotometer. Data were evaluated with 2-way analysis of variance, one way analysis of variance and Tukey post hoc tests. Results: The highest discoloration of all materials was observed after contact with CHX. In the MTA Angelus and CEM cement groups, significant differences were observed between CHX and NaOCl and also between these two irrigants with the other three irrigants (p < 0.05. In the Biodentine group, CHX created statistically significant discoloration compared to other irrigants (p < 0.05. Only wMTA Angelus showed a significantly higher discoloration in contact with EDTA compared to normal saline and dry condition (p < 0.05. wMTA Angelus showed a significantly higher colour change compared with CEM cement and Biodentine after contact with NaOCl, CHX, and EDTA (p < 0.05. Conclusions: The contact of wMTA, CEM cement, and Biodentine with CHX should be avoided because this leads to severe discoloration. Contact with sodium hypochlorite also leads to discoloration of wMTA and CEM cements. Among of the three tested materials, w

Soil Chemistry after Irrigation with Treated Wastewater in Semiarid Climate

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Pedro Carlos Pacheco de Oliveira

2016-01-01

Full Text Available ABSTRACT Soil irrigation using treated wastewater in the Brazilian semiarid region is a promising practice as this area currently faces water scarcity and pollution of water resources by domestic sewage. The aim of this study was to evaluate the use of treated wastewater in drip irrigation and its effect on the chemistry of soil cultivated with squash (Cucurbita maxima Duch. Coroa IAC and to verify whether there was an increase in soil salinity under a semiarid climate. The experiment was conducted for 123 days on a farm close to the sewage treatment plant, in a randomized block design with five treatments and four replications. The treatments consisted of two irrigation water depths (100 and 150 % of the evapotranspiration, two applications of gypsum to attenuate wastewater sodicity (0 and 5.51 g per plant, and a control treatment with no application of wastewater or gypsum. During the experiment, treated wastewater and soil gravitational water, at a depth of 0.40 m, were collected for measurement of Na+, K+, Ca2+, Mg2+, NO−3, NH4+, Cl− , alkalinity, electrical conductivity, pH and sodium adsorption ratio. At the end of the experiment, soil samples were collected at depths of 0.00-0.10, 0.10-0.20, and 0.20-0.40 m; and pH, total N, organic C, exchangeable cations and electrical conductivity of the saturation extract (CEs were analyzed. Besides an increase in pH and a reduction in total N, the irrigation with wastewater reduces soil salinity of the naturally salt-rich soils of the semiarid climate. It also led to soil sodification, in spite of the added gypsum, which indicates that irrigation with wastewater might require the addition of greater quantities of gypsum to prevent physical degradation of the soil.

Simple Myths and Basic Maths about Greening Irrigation

Science.gov (United States)

Dionisio Pérez-Blanco, C.; Gómez, C. Mario

2014-05-01

Managing water is a very complex societal issue that needs to involve legal, environmental, technological, financial and political considerations that are difficult to co-ordinate in an effective manner. This complexity and the lack of an agreed assessment framework have often implied that political decisions, largely driven by transaction costs (especially the bargaining costs required to come to an acceptable agreement with all the parties involved), have overshadowed and prevailed over other considerations. As a result, (financially) expensive solutions such as irrigation modernization programmes have been preferred to their inexpensive alternatives to save water, such as quotas or pricing policies. However, greening the economy is mostly about improving water governance and not only about putting the existing resource saving technical alternatives into practice. Focusing on the second and forgetting the first risks finishing with a highly efficient use of water services at the level of each individual user but with an unsustainable amount of water use for the entire economy. This might be happening already in many places with the modernization of irrigated agriculture, the world's largest water user and the one offering the most promising water saving opportunities. In spite of high expectations, costly modern irrigation techniques seem not to be contributing to reduce water scarcity and increase drought resiliency. In fact, according to the little evidence available, in some areas they are resulting in higher water use. Building on basic economic principles this study aims to show the conditions under which this apparently paradoxical outcome, known as the Jevons' Paradox, might appear. This basic model is expected to serve as guidance for assessing the actual outcomes of increasing irrigation efficiency and to discuss the changes in water governance that would be required for this to make a real contribution to sustainable water management.

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

Reconstructing the Spatio-Temporal Development of Irrigation Systems in Uzbekistan Using Landsat Time Series

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Thomas Koellner

2012-12-01

Full Text Available The expansion of irrigated agriculture during the Soviet Union (SU era made Central Asia a leading cotton production region in the world. However, the successor states of the SU in Central Asia face on-going environmental damages and soil degradation that are endangering the sustainability of agricultural production. With Landsat MSS and TM data from 1972/73, 1977, 1987, 1998, and 2000 the expansion and densification of the irrigated cropland could be reconstructed in the Kashkadarya Province of Uzbekistan, Central Asia. Classification trees were generated by interpreting multitemporal normalized difference vegetation index data and crop phenological knowledge. Assessments based on image-derived validation samples showed good accuracy. Official statistics were found to be of limited use for analyzing the plausibility of the results, because they hardly represent the area that is cropped in the very dry study region. The cropping area increased from 134,800 ha in 1972/73 to 470,000 ha in 2009. Overlaying a historical soil map illustrated that initially sierozems were preferred for irrigated agriculture, but later the less favorable solonchaks and solonetzs were also explored, illustrating the strategy of agricultural expansion in the Aral Sea Basin. Winter wheat cultivation doubled between 1987 and 1998 to approximately 211,000 ha demonstrating its growing relevance for modern Uzbekistan. The spatial-temporal approach used enhances the understanding of natural conditions before irrigation is employed and supports decision-making for investments in irrigation infrastructure and land cultivation throughout the Landsat era.

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

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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

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 ...

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

REGULATED DEFICIT IRRIGATION AND DIFFERENT MULCH TYPES ON FRUIT QUALITY AND YIELD OF WATERMELON

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KLEITON ROCHA SARAIVA

2017-01-01

Full Text Available The objective of this work was to assess the pulp resistance, soluble solids and yield of watermelon fruits grown under different irrigation managements (determined by the ISAREG model and mulches, and their interactions. After a survey carried out on local producers, two experiments were conducted, using a completely randomized block design in split - plot arrangement with four replications, in the Teaching, Research and Extension Unit (UEPE of the Federal Institute of Ceara (IFCE, Jaguaribe - Apodi Irrigation District (DIJA, State of Ceara, Brazil. The treatments consisted of four irrigation managements in the plots, M1 (100% of the available - water capacity (AWC of the soil, M2 (80%, M3 (60% and M4 (average water depth used by local producers and four mulch types in the sub - plots, without mulching (C0 with rice husk (C1, white plastic (C2 and black plastic (C3 as mulches. The results were subjected to analysis of variance, and significant results were subjected to regression (irrigation managements, average test (mulches and trend graphs (interaction between the factors. The irrigation management practiced during the watermelon crop cycle by the local producers of the Irrigation District of Jaguaribe - Apodi (DIJA in the State of Ceara, Brazil, is not appropriated, since they usually apply more water than the highest water depth determined by the ISAREG model (100% of the AWC. The plants grown under irrigation water depth of 365.20 mm (M1 and soils with mulches of rice husk or white plastic had the highest yields and fruits with better quality of soluble solids and pulp resistance.

Representing Farmer Irrigation Decisions in Northern India: Model Development from the Bottom Up.

Science.gov (United States)

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

2017-12-01

The plains of northern India are among the most intensely populated and irrigated regions of the world. Sustaining water demand has been made possible by exploiting the vast and hugely productive aquifers underlying the Indo-Gangetic basin. However, an increasing demand from a growing population and highly variable socio-economic and environmental variables mean present resources may not be sustainable, resulting in water security becoming one of India's biggest challenges. Unless solutions which take into consideration the regions evolving anthropogenic and environmental conditions are found, the sustainability of India's water resources looks bleak. Understanding water user decisions and their potential outcome is important for development of suitable water resource management options. Computational models are commonly used to assist water use decision making, typically representing natural processes well. The inclusion of human decision making however, one of the dominant drivers of change, has lagged behind. Improved representation of irrigation water user behaviour within models provides more accurate, relevant information for irrigation management. This research conceptualizes and proceduralizes observed farmer irrigation practices, highlighting feedbacks between the environment and livelihood. It is developed using a bottom up approach, informed through field experience and stakeholder interaction in Uttar Pradesh, northern India. Real world insights are incorporated through collected information creating a realistic representation of field conditions, providing a useful tool for policy analysis and water management. The modelling framework is applied to four districts. Results suggest predicted future climate will have little direct impact on water resources, crop yields or farmer income. In addition, increased abstraction may be sustainable in some areas under carefully managed conditions. By simulating dynamic decision making, feedbacks and interactions

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

Irrigated agriculture is the major consumer of surface water in Brazil using over 70% of the total supply. Due to the growing competition for water among different sectors of the economy, sustainable water use can only be achieved by decreasing the portion of water used by the irrigated agriculture. Thus, in order to maintain yield, farmers need to irrigate more efficiently. There is little known on irrigation efficiency in Brazil. Therefore a study was carried out in the Buriti Vermelho basin to assess the irrigation performance of existing system. The experimental basin has a drainage area of 940 hectares and is located in the eastern part of the Federal District, in the Brazilian savanna region. Agriculture is the main activity. There is a dominance of red latosols. Several types of land use and crop cover are encountered in the basin. Conflicts among farmers for water are increasing. As water, in quality and quantity, is crucial to maintain the livelihood of the population in the basin, concern about risk of water lack due to climatic and land use change is in place. Once irrigation is the main water user in the basin, to increase water availability and reduce conflicts a water resource management plan has to be established. For this purpose, irrigation system performance has to be understood. The objective of this work was to assess the performance and the management of irrigation (small and big) that has been carried out by farmers in the Buriti Vermelho experimental watershed. A survey undertaken in 2007 was used to identify the irrigation systems in the basin. It was verified that irrigation is practiced by both small (area up to 6 hectare) and big farmers. Small farmers usually crop limes and vegetables and use micro-irrigation, drip, sprinkler, guns or furrow to irrigate them. Big farmers plant annual crops and use center pivot as irrigation system. In this first assessment 13 irrigation systems were evaluated: five conventional sprinklers, four drip

Use of Irrigation to Extend the Seeding Window for Final Reclamation at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

TRW Environmental Safety

2000-01-01

plots sown in December, February, and March, and showed no response to irrigation on plots sown in April. Therefore, early spring irrigation did not facilitate establishment of warm-season species. These results suggest that these species are dependent upon precipitation while temperatures are warm in late summer or fall. However, control plots that were seeded in December had acceptable densities of these species. A more practical approach might be to avoid irrigation costs by seeding in December and waiting for fall precipitation. The remaining species (cool-season species) showed an opposite response to supplemental water with greater densities on irrigated plots sown in February, March, and April, and no response to irrigation on plots sown in December. While these results show that irrigation can extend the seeding window for cool-season species should it be necessary, it was also apparent that if seeds are sown by late December, irrigation is not necessary to achieve acceptable plant densities

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)

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)

Linked hydrologic and social systems that support resilience of traditional irrigation communities

Science.gov (United States)

Fernald, A.; Guldan, S.; Boykin, K.; Cibils, A.; Gonzales, M.; Hurd, B.; Lopez, S.; Ochoa, C.; Ortiz, M.; Rivera, J.; Rodriguez, S.; Steele, C.

2015-01-01

Southwestern US irrigated landscapes are facing upheaval due to water scarcity and land use conversion associated with climate change, population growth, and changing economics. In the traditionally irrigated valleys of northern New Mexico, these stresses, as well as instances of community longevity in the face of these stresses, are apparent. Human systems have interacted with hydrologic processes over the last 400 years in river-fed irrigated valleys to create linked systems. In this study, we ask if concurrent data from multiple disciplines could show that human-adapted hydrologic and socioeconomic systems have created conditions for resilience. Various types of resiliencies are evident in the communities. Traditional local knowledge about the hydrosocial cycle of community water management and ability to adopt new water management practices is a key response to disturbances such as low water supply from drought. Livestock producers have retained their irrigated land by adapting: changing from sheep to cattle and securing income from outside their livestock operations. Labor-intensive crops decreased as off-farm employment opportunities became available. Hydrologic resilience of the system can be affected by both human and natural elements. We find, for example, that there are multiple hydrologic benefits of traditional irrigation system water seepage: it recharges the groundwater that recharges rivers, supports threatened biodiversity by maintaining riparian vegetation, and ameliorates impacts of climate change by prolonging streamflow hydrographs. Human decisions to transfer water out of agriculture or change irrigation management, as well as natural changes such as long-term drought or climate change, can result in reduced seepage and the benefits it provides. We have worked with the communities to translate the multidisciplinary dimensions of these systems into a common language of causal loop diagrams, which form the basis for modeling future scenarios to

The System Nobody Sees: Irrigated Wetland Management and Alpaca Herding in the Peruvian Andes

NARCIS (Netherlands)

Verzijl, A.; Guerrero Quispe, S.

2013-01-01

Increasingly, attention in regional, national, and international water governance arenas has focused on high-altitude wetlands. However, existing local water management practices in these wetlands are often overlooked. This article looks at the irrigation activities of alpaca herders in the

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

Science.gov (United States)

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

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.

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

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.

[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

Analysis of water footprints of rainfed and irrigated crops in Sudan

Directory of Open Access Journals (Sweden)

Shamseddin Musa Ahmed

2011-12-01

Full Text Available Water rather than land is the limiting factor for crop production in Sudan. This study attempts to use the water footprint (WFP and virtual water concepts to account for crops water consumption under the Sudanese rainfed and irrigated conditions. The general average of the green WFP of sorghum and millet were found to be about 7700 and 10700 m3 ton-1, respectively. According to experimental results at three different climates, in-situ rainwater harvesting techniques could reduce the WFP of rainfed sorghum by 56% on the average. The blue component (surface water shows the highest contribution to the total WFP of irrigated crops: 88% for cotton, 70% for sorghum, 68% for groundnut and 100% for wheat. However, the role of the green water (rainwater is not marginal since it largely influences the operation and maintenance (silt clearance of the gravity-fed irrigation system. Under normal conditions, the annual total virtual water demand of sorghum (the dominant food crop in Sudan is found to be 15 km3, of which 91% is green water. During a dry year, however, Sudan could experience a deficit of 2.3 km3 of water, necessitating the adoption of a wise food stocking-exporting policy.

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.

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...

Unsaturated flow dynamics during irrigation with wastewater: field and modelling study

Science.gov (United States)

Martinez-Hernandez, V.; de Miguel, A.; Meffe, R.; Leal, M.; González-Naranjo, V.; de Bustamante, I.

2012-04-01

To deal with water scarcity combined with a growing water demand, the reuse of wastewater effluents of wastewater treatment plants (WWTP) for industrial and agricultural purposes is considered as a technically and economically feasible solution. In agriculture, irrigation with wastewater emerges as a sustainable practice that should be considered in such scenarios. Water infiltration, soil moisture storage and evapotranspiration occurring in the unsaturated zone are fundamental processes that play an important role in soil water balance. An accurate estimation of unsaturated flow dynamics (during and after irrigation) is essential to improve wastewater management (i.e. estimating groundwater recharge or maximizing irrigation efficiency) and to avoid possible soil and groundwater affections (i.e. predicting contaminant transport). The study site is located in the Experimental Plant of Carrión de los Céspedes (Seville, Spain). Here, treated wastewater is irrigated over the soil to enhance plants growth. To obtain physical characteristics of the soil (granulometry, bulk density and water retention curve), soil samples were collected at different depths. A drain gauge passive capillary lysimeter was installed to determine the volume of water draining from the vadose zone. Volumetric water content of the soil was monitored by measuring the dielectric constant using capacitance/frequency domain technology. Three soil moisture probes were located at different depths (20, 50 and 70 cm below the ground surface) to control the variation of the volumetric water content during infiltration. The main aim of this study is to understand water flow dynamics through the unsaturated zone during irrigation by using the finite element model Hydrus-1D. The experimental conditions were simulated by a 90 cm long, one dimensional solution domain. Specific climatic conditions, wastewater irrigation rates and physical properties of the soil were introduced in the model as input parameters

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

temperatures and future recharge rates in the east will resemble present recharge rates in the western part of the northern High Plains aquifer. The reductions in recharge rates could accelerate declining water levels if irrigation demand and other management strategies are not implemented. Findings here have important implications for future management of irrigation practices and to slow groundwater depletion in this important agricultural region.

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.

APPROACH TO CONSTRUCTING 3D VIRTUAL SCENE OF IRRIGATION AREA USING MULTI-SOURCE DATA

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S. Cheng

2015-10-01

Full Text Available For an irrigation area that is often complicated by various 3D artificial ground features and natural environment, disadvantages of traditional 2D GIS in spatial data representation, management, query, analysis and visualization is becoming more and more evident. Building a more realistic 3D virtual scene is thus especially urgent for irrigation area managers and decision makers, so that they can carry out various irrigational operations lively and intuitively. Based on previous researchers' achievements, a simple, practical and cost-effective approach was proposed in this study, by adopting3D geographic information system (3D GIS, remote sensing (RS technology. Based on multi-source data such as Google Earth (GE high-resolution remote sensing image, ASTER G-DEM, hydrological facility maps and so on, 3D terrain model and ground feature models were created interactively. Both of the models were then rendered with texture data and integrated under ArcGIS platform. A vivid, realistic 3D virtual scene of irrigation area that has a good visual effect and possesses primary GIS functions about data query and analysis was constructed.Yet, there is still a long way to go for establishing a true 3D GIS for the irrigation are: issues of this study were deeply discussed and future research direction was pointed out in the end of the paper.

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

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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.

Review of root canal irrigant delivery techniques and devices

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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.

Reconciling irrigated food production with environmental flows for Sustainable Development Goals implementation.

Science.gov (United States)

Jägermeyr, Jonas; Pastor, Amandine; Biemans, Hester; Gerten, Dieter

2017-07-19

Safeguarding river ecosystems is a precondition for attaining the UN Sustainable Development Goals (SDGs) related to water and the environment, while rigid implementation of such policies may hamper achievement of food security. River ecosystems provide life-supporting functions that depend on maintaining environmental flow requirements (EFRs). Here we establish gridded process-based estimates of EFRs and their violation through human water withdrawals. Results indicate that 41% of current global irrigation water use (997 km 3 per year) occurs at the expense of EFRs. If these volumes were to be reallocated to the ecosystems, half of globally irrigated cropland would face production losses of ≥10%, with losses of ∼20-30% of total country production especially in Central and South Asia. However, we explicitly show that improvement of irrigation practices can widely compensate for such losses on a sustainable basis. Integration with rainwater management can even achieve a 10% global net gain. Such management interventions are highlighted to act as a pivotal target in supporting the implementation of the ambitious and seemingly conflicting SDG agenda.

Reconciling irrigated food production with environmental flows for Sustainable Development Goals implementation

Science.gov (United States)

Jägermeyr, Jonas; Pastor, Amandine; Biemans, Hester; Gerten, Dieter

2017-07-01

Safeguarding river ecosystems is a precondition for attaining the UN Sustainable Development Goals (SDGs) related to water and the environment, while rigid implementation of such policies may hamper achievement of food security. River ecosystems provide life-supporting functions that depend on maintaining environmental flow requirements (EFRs). Here we establish gridded process-based estimates of EFRs and their violation through human water withdrawals. Results indicate that 41% of current global irrigation water use (997 km3 per year) occurs at the expense of EFRs. If these volumes were to be reallocated to the ecosystems, half of globally irrigated cropland would face production losses of >=10%, with losses of ~20-30% of total country production especially in Central and South Asia. However, we explicitly show that improvement of irrigation practices can widely compensate for such losses on a sustainable basis. Integration with rainwater management can even achieve a 10% global net gain. Such management interventions are highlighted to act as a pivotal target in supporting the implementation of the ambitious and seemingly conflicting SDG agenda.

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

Size and stochasticity in irrigated social-ecological systems

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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.

An integrated approach to assess the dynamics of a peri-urban watershed influenced by wastewater irrigation

Science.gov (United States)

Mahesh, Jampani; Amerasinghe, Priyanie; Pavelic, Paul

2015-04-01

In many urban and peri-urban areas of India, wastewater is under-recognized as a major water resource. Wastewater irrigated agriculture provides direct benefits for the livelihoods and food security of many smallholder farmers. A rapidly urbanizing peri-urban micro-watershed (270 ha) in Hyderabad was assessed over a 10-year period from 2000 to 2010 for changes in land use and associated farming practices, farmer perceptions, socio-economic evaluation, land-use suitability for agriculture and challenges in potential irrigated area development towards wastewater use. This integrated approach showed that the change in the total irrigated area was marginal over the decade, whereas the built-up area within the watershed boundaries doubled and there was a distinct shift in cropping patterns from paddy rice to paragrass and leafy vegetables. Local irrigation supplies were sourced mainly from canal supplies, which accounted for three-quarters of the water used and was largely derived from wastewater. The remainder was groundwater from shallow hard-rock aquifers. Farmer perception was that the high nutrient content of the wastewater was of value, although they were also interested to pay modest amounts for additional pre-treatment. The shift in land use towards paragrass and leafy vegetables was attributed to increased profitability due to the high urban demand. The unutilised scrubland within the watershed has the potential for irrigation development, but the major constraints appear to be unavailability of labour and high land values rather than water availability. The study provides evidence to support the view that the opportunistic use of wastewater and irrigation practices, in general, will continue even under highly evolving peri-urban conditions, to meet the livelihood needs of the poor driven by market demands, as urban sprawl expands into cultivable rural hinterlands. Policy support is needed for enhanced recognition of wastewater for agriculture, with flow

Estimating Leaching Requirements for Barley Growth under Saline Irrigation

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Ahmed Al-Busaidi

2012-01-01

Full Text Available The utilization of marginal water resources for agriculture is receiving considerable attention. The lands irrigated with saline water are required to reduce salt accumulations through leaching and/or drainage practices. A field experiment was carried out to investigate the effect of saline irrigation and leaching fraction on barley (Hordeum vulgare L. growth. For this purpose highly saline water was diluted to the salinity levels of 3, 6 and 9 dS m-1 and applied by drip irrigation at 0.0, 0.15, 0.20 and 0.25 leaching fractions (LF. The results of the experiment showed that both quantity and quality of water regulated salts distribution within the soil in the following manner: a the salts were found higher near or immediate below the soil surface; b an enhanced LF carried more salts down the soil horizon but there was no significant difference in plant yield between different treatments of leaching fractions. Salinity of water significantly impaired barley growth. The good drainage of sandy soil enhanced the leaching process and minimized the differences between leaching fractions. The increment in saline treatments (3, 6 and 9 dS m-1 added more salts and stressed plant growth. However, the conjunctive use of marginal water at proportional LF could be effective in enhancing the yield potential of crops in water-scarce areas.

The impact of sewage irrigation on the uptake of mercury in corn plants (Zea mays) from suburban Beijing

International Nuclear Information System (INIS)

Rothenberg, S.E.; Du, X.; Zhu, Y.-G.; Jay, J.A.

2007-01-01

The impact of sewage irrigation on the uptake and translocation of mercury (Hg) in corn plants (Zea mays) was investigated. Corn plants were harvested the same day from two nearby fields in suburban Beijing, one irrigated historically with sewage effluent, and one irrigated solely with groundwater. Hg content was analyzed in the soil, roots and stems, while percent moisture and soil organic content were analyzed in the soil samples. The concentration of Hg in the soil and roots, and the soil organic content were not significantly different between the two fields, despite the historic practice of sewage irrigation. Hg content in roots was positively correlated with soil Hg concentration (r = 0.95, n = 6). The transfer coefficients between roots and stems were significantly higher in the control site (control: 2.06, sewage-irrigated: 0.44, p < 0.05), indicating that the barrier effect of the roots was not consistent between the two fields. - Hg content in the roots of corn plants (Zea mays) was positively correlated with soil Hg content, but negatively correlated with Hg content in stems

The impact of sewage irrigation on the uptake of mercury in corn plants (Zea mays) from suburban Beijing

Energy Technology Data Exchange (ETDEWEB)

Rothenberg, S.E. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085 (China); Environmental Science and Engineering Program, Box 951772 CHS, University of California, Los Angeles, CA 90095-1772 (United States)], E-mail: srothenb@ucla.edu; Du, X.; Zhu, Y.-G. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085 (China); Jay, J.A. [Department of Civil and Environmental Engineering, Box 951593 Boelter Hall, University of California, Los Angeles, CA 90095-1593 (United States)

2007-09-15

The impact of sewage irrigation on the uptake and translocation of mercury (Hg) in corn plants (Zea mays) was investigated. Corn plants were harvested the same day from two nearby fields in suburban Beijing, one irrigated historically with sewage effluent, and one irrigated solely with groundwater. Hg content was analyzed in the soil, roots and stems, while percent moisture and soil organic content were analyzed in the soil samples. The concentration of Hg in the soil and roots, and the soil organic content were not significantly different between the two fields, despite the historic practice of sewage irrigation. Hg content in roots was positively correlated with soil Hg concentration (r = 0.95, n = 6). The transfer coefficients between roots and stems were significantly higher in the control site (control: 2.06, sewage-irrigated: 0.44, p < 0.05), indicating that the barrier effect of the roots was not consistent between the two fields. - Hg content in the roots of corn plants (Zea mays) was positively correlated with soil Hg content, but negatively correlated with Hg content in stems.

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.

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

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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

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

ASPECTS OF DRIP IRRIGATION ON SLOPES

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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.

Policy Incentives for Reducing Nitrate Leaching in Agricultural Lands: A Case Study of Irrigation and Drainage Dorudzan

International Nuclear Information System (INIS)

Sheikhzeinoddin, A.; Esmaeili, A.; Zibaei, M.

2016-01-01

Agricultural activities increasingly use water, fertilizers and pesticides, which may generate negative impacts on environment. Nowadays, nitrogen leaching from agricultural lands is a widespread global problem. Therefore, alternative land management practices such as nutrient management (rate, method and time of application), tillage operations (conservation and no-tillage), and irrigation management are routinely used to reduce non-point source pollution and improve water quality. In fact, a number of studies have illustrated the positive effects of best management practices on water and nutrient losses. The objective of this paper is to develop a bio-economic model and introducing the policy instrument for reducing nitrate from irrigation and drainage Dorudzan. We aim to identify ‘‘win–win’’ opportunities for improving farm profitability and reducing nitrate leaching.

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 ...

Hyperspectral remote sensing analysis of short rotation woody crops grown with controlled nutrient and irrigation treatments

Science.gov (United States)

Jungho Im; John R. Jensen; Mark Coleman; Eric. Nelson

2009-01-01

Hyperspectral remote sensing research was conducted to document the biophysical and biochemical characteristics of controlled forest plots subjected to various nutrient and irrigation treatments. The experimental plots were located on the Savannah River Site near Aiken, SC. AISA hyperspectral imagery were analysed using three approaches, including: (1) normalized...

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

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 others might consider improving their trade policy to avoid food shortage.

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.

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

Effects of irrigation levels on interactions among Lygus hesperus (Hemiptera: Miridae), insecticides, and predators in cotton.

Science.gov (United States)

Asiimwe, Peter; Naranjo, Steven E; Ellsworth, Peter C

2014-04-01

Variation in plant quality and natural enemy abundance plays an important role in insect population dynamics. In manipulative field studies, we evaluated the impact of varying irrigation levels and insecticide type on densities of Lygus hesperus Knight and the arthropod predator community in cotton. Three watering levels were established via irrigations timed according to three levels of percent soil water depletion (SWD): 20, 40, or 60, where 40% SWD is considered standard grower practice, 60% represents a deficit condition likely to impose plant productivity losses, and 20% represents surplus conditions with likely consequences on excessive vegetative plant production. The two key L. hesperus insecticides used were the broad-spectrum insecticide acephate and the selective insecticide flonicamid, along with an untreated check. We hypothesized that densities of L. hesperus and its associated predators would be elevated at higher irrigation levels and that insecticides would differentially impact L. hesperus and predator dynamics depending on their selectivity. L. hesperus were more abundant at the higher irrigation level (20% SWD) but the predator densities were unaffected by irrigation levels. Both L. hesperus and its predators were affected by the selectivity of the insecticide with highest L. hesperus densities and lowest predator abundance where the broad spectrum insecticide (acephate) was used. There were no direct interactions between irrigation level and insecticides, indicating that insecticide effects on L. hesperus and its predators were not influenced by the irrigation levels used here. The implications of these findings on the overall ecology of insect-plant dynamics and yield in cotton are discussed.

Normal or abnormal? 'Normative uncertainty' in psychiatric practice.

Science.gov (United States)

Bassett, Andrew M; Baker, Charley

2015-06-01

The 'multicultural clinical interaction' presents itself as a dilemma for the mental health practitioner. Literature describes two problematic areas where this issues emerges--how to make an adequate distinction between religious rituals and the rituals that may be symptomatic of 'obsessive compulsive disorder' (OCD), and how to differentiate 'normative' religious or spiritual beliefs, behaviours, and experiences from 'psychotic' illnesses. When it comes to understanding service user's 'idioms of distress', beliefs about how culture influences behaviour can create considerable confusion and 'normative uncertainty' for mental health practitioners. In the absence of clear diagnostic and assessment criteria on distinguishing between 'culture' and 'psychopathology', practitioners have had to rely on their own intuition and seek out possible 'strategies' or 'procedures' from a contradictory and cross-disciplinary evidence base. Decontextualisation of service users' experiences may result in the pathologisation of culturally 'normative' phenomenon, 'category fallacy' errors, and poor health care experiences and outcomes for service users.This paper situates this dilemma within a wider debate that has concerned both the biomedical and social sciences, namely, the unresolved question of 'normality' or 'abnormality'. Indeed, issues that arise from dilemmas surrounding the question of 'culture' or 'psychopathology' are intimately tied to wider cultural ideas about what is considered 'normal'. The disciplines of psychiatry, psychology, and medical anthropology have struggled to establish workable criteria against which to judge behaviour as 'normal', 'abnormal', or 'pathological'. Three models for understanding mental 'abnormality' are evident in 'transcultural psychiatry' (what is now commonly known as 'cultural psychiatry'), and these models have corresponded closely to the interpretive models used by anthropologists attempting to make sense of the apparent diversity of

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

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.

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

Response of lupine plants irrigated with saline water to rhizobium inoculation using 15N-isotope dilution

International Nuclear Information System (INIS)

Gadalla, A.M.; El-Ghandour, I.A.; Abdel Aziz, H.A.; Hamdy, A.; Aly, M.M.

2002-01-01

The lupine Rhizobium symbiosis and contribution of N 2 fixation under different levels of irrigation water salinity were examined. Lysimeter experiment was established under greenhouse conditions during the year 2002-2003. In this experiment, inoculated plants were imposed to different salinity levels of irrigation water and N-fertilizer treatment. Plant height was decreased under different salinity levels, nitrogen treatments and bacterial inoculation. Similar trend was noticed with leaf area. The highest leaf area was recorded with salt tolerant bacterial inoculation (SBI) and splitting N-treatment. Highest values of N-uptake occurred after 100 day intervals under the tested factors. Relative decrease in N-uptake did not exceed 40% of those recorded with the fresh water treatment as affected by experimental factors. Nitrogen uptake by the whole plant reflected an increase at 3 dS/m salinity level of irrigation water. Relative increases were 5% and 15% for normal bacteria inoculation under single dose (NI) and splitting

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

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.

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.

You Are How You Eat? Femininity, Normalization, and Veganism as an Ethical Practice of Freedom

OpenAIRE

Megan A. Dean

2014-01-01

In this paper I argue that the practice of veganism is, or can be, a Foucauldian ethical practice of freedom. I begin by sketching out the problematization of alimentary practices within a normalizing patriarchal framework, which some feminists argue is dominant within contemporary North American society. Within this problematization, eating—for many women—is a way to manage the body’s appearance and bring it into conformity with feminine norms, and also an ongoing opportunity to exercise the...

Effect of Irrigation and Preplant Nitrogen Fertilizer Source on Maize in the Southern Great Plains

Directory of Open Access Journals (Sweden)

Jacob T. Bushong

2014-01-01

Full Text Available With the demand for maize increasing, production has spread into more water limited, semiarid regions. Couple this with the increasing nitrogen (N fertilizer costs and environmental concerns and the need for proper management practices has increased. A trial was established to evaluate the effects of different preplant N fertilizer sources on maize cultivated under deficit irrigation or rain-fed conditions on grain yield, N use efficiency (NUE, and water use efficiency (WUE. Two fertilizer sources, ammonium sulfate (AS and urea ammonium nitrate (UAN, applied at two rates, 90 and 180 kg N ha−1, were evaluated across four site-years. Deficit irrigation improved grain yield, WUE, and NUE compared to rain-fed conditions. The preplant application of a pure ammoniacal source of N fertilizer, such as AS, had a tendency to increase grain yields and NUE for rain-fed treatments. Under irrigated conditions, the use of UAN as a preplant N fertilizer source performed just as well or better at improving grain yield compared to AS, as long as the potential N loss mechanisms were minimized. Producers applying N preplant as a single application should adjust rates based on a reasonable yield goal and production practice.

Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

Science.gov (United States)

Kong, Ping; Richardson, Patricia; Hong, Chuanxue

2017-01-01

Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible.

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.

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.

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

Directory of Open Access Journals (Sweden)

Qingfeng Miao

2018-01-01

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

Rice Photosynthetic Productivity and PSII Photochemistry under Nonflooded Irrigation

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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.

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.

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

Science.gov (United States)

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

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.

Possibilities for conservation and efficiency of irrigation systems in hydropower; Possibilidades de conservacao e eficientizacao hidroenergetica em sistemas de irrigacao

Energy Technology Data Exchange (ETDEWEB)

Viana, Augusto Nelson Carvalho; Ricardo, Mateus [Universidade Federal de Itajuba (UNIFEI), MG (Brazil). Grupo de Energia], emails: augusto@unifei.edu.br, mateus@unifei.edu.br

2008-07-01

This paper presents a literature review on efficiency and conservation of electricity and water in irrigation systems, focusing on the pumping systems used for that purpose. It's made an introduction to the theory about pumping systems and irrigation, which provides the conceptual basis for the understanding of the technologies and best practices on conservation and rational use of water and electricity presented in the paper development. (author)

Silicone Oil Removal from Aphakic Eyes Using a Side Irrigating Cannula

Directory of Open Access Journals (Sweden)

Touka Banaee

2008-12-01

Full Text Available

In an interventional case series, 11 aphakic eyes of 11 patients with previous vitrectomy and silicone oil tamponade underwent passive silicone oil removal under topical anesthesia through a single clear cornea incision with use of a side irrigating phacoemulsification irrigation cannula without performing a sclerotomy. All procedures were simple, short and uncomplicated. The only observed complication was minimal localized corneal edema the day after the procedure, which resolved within 1-2 days. Use of a side irrigating cannula permits safe and simple removal of silicone oil under topical anesthesia through a single clear cornea incision without need for sclerotomy.