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Sample records for horticultural irrigation water

  1. Satellite Mapping of Horticultural Crop Cover in California's San Joaquin Valley - Potenial for Irrigation Water Resource Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimation of crop water use, and associated irrigation demand, is commonly addressed by application of so-called crop coefficients, which express water loss as a proportion of evapotranspiration from a well-characterized reference crop such as grass or alfalfa. For horticultural crops, however, pla...

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

    PubMed

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

    2016-07-01

    Petrifilms are dehydrated agar culture plates that have been used to quantify colony forming units (CFU) mL of either aerobic bacteria (Petrifilm-AC) or fungus (Petrifilm-YM), depending on substrate composition. Microbes in irrigation systems can indicate biofilm risk and potential clogging of irrigation emitters. The research objective was to compare counts on Petrifilms versus traditional, hydrated-agar plates using samples collected from recirculated irrigation waters and cultures of isolated known species. The estimated count (in CFU mL) from a recirculated irrigation sample after 7 d of incubation on Petrifilm-YM was only 5.5% of the count quantified using sabouraud dextrose agar (SDA) with chloramphenicol after 14 d. In a separate experiment with a known species, Petrifilm-YM did not successfully culture zoospores of . Isolates of viable zoospores were cultured successfully on potato-dextrose agar (PDA), with comparable counts with a vegetable juice medium supplemented with the antibiotics pimaricin, ampicillin, rifamycin, pentochloronitrobenzene and hymexazol (PARP-H). The quantification of pv. Begoniaceae on Petrifilm-AC was not significantly different ( < 0.05) than on PDA, but was lower than on Reasoner and Goldrich agar (R2A) or with a hemocytometer. The current formulation of Petrifilm-YM is unlikely to be a useful monitoring method for plant pathogens in irrigation water because of the inability to successfully culture oomycetes. However, Petrifilm-AC was an effective method to quantify bacteria and can provide an easy-to-use on-farm tool to monitor biofilm risk and microbial density. PMID:27380096

  3. Spatial and Temporal Analysis of the Microbial Community in Slow Sand Filters Used for Treating Horticultural Irrigation Water

    PubMed Central

    Calvo-Bado, Leo A.; Pettitt, Tim R.; Parsons, Nick; Petch, Geoff M.; Morgan, J. Alun W.; Whipps, John M.

    2003-01-01

    An experimental slow sand filter (SSF) was constructed to study the spatial and temporal structure of a bacterial community suppressive to an oomycete plant pathogen, Phytophthora cryptogea. Passage of water through the mature sand column resulted in complete removal of zoospores of the plant pathogen. To monitor global changes in the microbial community, bacterial and fungal numbers were estimated on selective media, direct viable counts of fungal spores were made, and the ATP content was measured. PCR amplification of 16S rRNA genes and denaturing gradient gel electrophoresis (DGGE) were used to study the dynamics of the bacterial community in detail. The top layer (1 cm) of the SSF column was dominated by a variable and active microbial population, whereas the middle (50 cm) and bottom (80 cm) layers were dominated by less active and diverse bacterial populations. The major changes in the microbial populations occurred during the first week of filter operation, and these populations then remained to the end of the study. Spatial and temporal nonlinear mapping of the DGGE bands provided a useful visual representation of the similarities between SSF samples. According to the DGGE profile, less than 2% of the dominating bands present in the SSF column were represented in the culturable population. Sequence analysis of DGGE bands from all depths of the SSF column indicated that a range of bacteria were present, with 16S rRNA gene sequences similar to groups such as Bacillus megaterium, Cytophaga, Desulfovibrio, Legionella, Rhodococcus rhodochrous, Sphingomonas, and an uncharacterized environmental clone. This study describes the characterization of the performance, and microbial composition, of SSFs used for the treatment of water for use in the horticultural industry. Utilization of naturally suppressive population of microorganisms either directly or by manipulation of the environment in an SSF may provide a more reproducible control method for the future. PMID

  4. Wastewater treatment by a modular, domestic-scale reedbed system for safe horticultural irrigation.

    PubMed

    Derry, Chris; Maheshwari, Basant

    2015-12-15

    The aim of the study was to assess the sequential treatment performance of a commercial, domestic-scale modular reedbed system intended to provide safe horticultural irrigation water. Previously only mechanical treatment systems involving forced aeration with subsequent disinfection, usually by tablet-chlorination, had been accredited in Australia. The modular design of the hybrid, subsurface-flow reedbed system offered 5 control points where monitoring and management of the treatment train could be carried out. Ten chemical parameters (chemical and biochemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, total nitrogen, dissolved oxygen percentage saturation and suspended solids) and 4 microbial parameters (total coliform, Escherichia coli, enterococci and Clostridium perfringens) reached satisfactory levels as a result of the treatment process. Health requirements for safe horticultural irrigation were met by the outlet of the second reedbed, providing a high level of treatment-backup capacity in terms of the remaining 2 reedbeds. This suggested that chlorination was a redundant backup precaution in treating irrigation water to the acceptable regional guideline level for all horticultural uses, including the spray irrigation of salad crops eaten raw. PMID:26282758

  5. Irrigation in a future of limited water supplies: Making every drop count. A Workshop Sponsored by the Water Utilization and Management Working Group of the American Society for Horticultural Sciences.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The production of horticultural crops, regardless of commodity, requires at the most basic level, light and water. While the sun will rise tomorrow, the prospects for rain are less certain. The occurrence of droughts and the increasing demands on water resources from municipal entities, presents ...

  6. Horticulture.

    ERIC Educational Resources Information Center

    Aitken, James

    This curriculum guide is intended to assist vocational instructors in preparing students for entry-level employment in the field of horticulture and getting them ready for advanced training in the workplace. The package contains a validated competency/skill and task list, an instructor's guide, and an annotated bibliography. The following…

  7. Treated sewage effluent (water) potential to be used for horticultural production in Botswana

    NASA Astrophysics Data System (ADS)

    Emongor, V. E.; Ramolemana, G. M.

    Botswana being semi-arid and arid country, the provision of drinking water and water for agricultural production is becoming increasingly scarce and expensive. Measures that can augment the available sources of water or measures that can reduce the demand on potable water should be given serious consideration. Horticulturists have incorporated new technology into many of their production programs, which has enabled them to grow more horticultural crops with less water; however, more effort is needed. Techniques such as drip irrigation, sensors, growing plants with low water requirements, timing and scheduling of irrigation to the growth needs of the plant, mulching, and establishing a minimum water quality standard for horticultural crops must be used to stretch agricultural water supplies. Recycling agricultural water and using treated municipal sewage effluent is a viable option for increasing horticultures’ future water supply in Botswana. Agriculture wastewater and sewage effluents often contain significant quantities of heavy metals and other substances that may be toxic to people but beneficial to horticultural crops. However, before sewage effluent can be used for commercial production of vegetables and fruits, research must be undertaken to determine whether there is accumulation of heavy metals and faecal coliforms in the edible portion of the horticultural produce which may be detrimental to human health 15-20 years later. Research must be undertaken to assess the impact of sewage effluent on soil physical, chemical properties and environment after continued use.

  8. Irrigation water quality assessments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing demands on fresh water supplies by municipal and industrial users means decreased fresh water availability for irrigated agriculture in semi arid and arid regions. There is potential for agricultural use of treated wastewaters and low quality waters for irrigation but this will require co...

  9. WATER REQUIREMENT OF IRRIGATED GARLIC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A replicated field trial was conducted on the West side of the San Joaquin Valley to determine the crop coefficient and water requirements of irrigated garlic. Irrigation systems used included flood irrigation, subsurface drip irrigation, and surface drip irrigation. Irrigation levels were set at 5...

  10. Water Requirements Of Irrigated Garlic

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A replicated field trial was conducted on the West side of the San Joaquin Valley to determine the crop coefficient and water requirements of irrigated garlic. Irrigation systems used included flood irrigation, subsurface drip irrigation, and surface drip irrigation. Irrigation levels were set at 5...

  11. EFFICACY OF NOVEL WATER DISINFECTION TECHNIQUES IN HORTICULTURAL NUTRIENT RECYCLING.

    PubMed

    Heungens, K; Clierinck, M; Inghelbrecht, S; Vissers, M

    2015-01-01

    Hydroponic systems used for growing potted ornamentals in greenhouses are commonly ebb-and-flow irrigation systems. The drainage water is usually recycled to save water and nutrients. To avoid the spread of pathogens in these closed irrigation systems, disinfection of the recycled water is standard practice. Growers can use slow sand filtration or UV-radiation techniques, but these methods are often either not sulted for specific problems or they require an excessively large investment. The objective of this study was to test less expensive but effective alternative disinfection systems. The efficacy of five disinfection systems against fungi and oomycetes was determined: Aqua-Hort (based on Cu-ions), Reciclean (performic acid), D1-OX Forte (CIO2), ECA (electrochemically activated water = anodic oxidation: hypochlorite and free radicals) and Newtec (also anodic oxidation). These five systems and a no-sterilization control were integrated in small closed ebb-and-flow circuits with nutrient solution reservoirs of 400 L each. Activity against Fusarium was excellent with ECA, good with Newtec and DI-OX Forte, moderate with high doses of Reciclean (250 ppm H2O2 and poor with the Aqua-Hort. There was no Pythium in the ECA and Newtec systems, while still so in the Aqua-Hort system, even at high doses (up to 7 ppm Cu++). Although the Reciclean (up to 100 ppm H2O2) and Aqua-Hort systems did not perform well against the pathogens, they did very well against algae; especially Reciclean was also useful against duckweed in water and liverwort on soil substrates. Concentrations of total Cl were elevated in water, substrate and plants after treatments with ECA and Newtec; other accumulations were Cu (Aqua-Hort), Na and SO4 (DI-OX Forte). However, only on a limited number of plant species these accumulations produced phytotoxic effects. PMID:27141749

  12. Soil water monitoring equipment for irrigation scheduling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Equipment for monitoring soil water content and sometimes bulk electrical conductivity can be used for scheduling irrigations if the accuracy of the equipment is sufficient to avoid damanging plants and wasting water and fertilizer. Irrigation scheduling is the process of deciding when to irrigate a...

  13. Crop water productivity and irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modern irrigation systems offer large increases in crop water productivity compared with rainfed or gravity irrigation, but require different management approaches to achieve this. Flood, sprinkler, low-energy precision application, LEPA, and subsurface drip irrigation methods vary widely in water a...

  14. Infiltration of unconsumed irrigation water in Utah

    USGS Publications Warehouse

    Brothers, William C.; Thiros, Susan A.

    1991-01-01

    The ground-water hydrology of Panguitch Valley and adjacent areas, south-central Utah, was studied during 1988-90. One objective of the study was to measure ground-water recharge from infiltration of unconsumed irrigation water. Water-level and soil-moisture data were used to estimate travel times for water moving down through the soil profile, and to compare quantities of water reaching the water table after application of flood and sprinkler irrigation. During this study, estimates of travel times from land surface to the water table ranged from 11 days in June 1989 to 2 days in September 1989. Estimates of irrigation water recharging the ground-water system ranged from 25 to 75 percent of the water applied to the flood-irrigated field. Virtually no recharge was apparent for the sprinkler-irrigated field.

  15. Lunar horticulture.

    NASA Technical Reports Server (NTRS)

    Walkinshaw, C. H.

    1971-01-01

    Discussion of the role that lunar horticulture may fulfill in helping establish the life support system of an earth-independent lunar colony. Such a system is expected to be a hybrid between systems which depend on lunar horticulture and those which depend upon the chemical reclamation of metabolic waste and its resynthesis into nutrients and water. The feasibility of this approach has been established at several laboratories. Plants grow well under reduced pressures and with oxygen concentrations of less than 1% of the total pressure. The carbon dioxide collected from the lunar base personnel should provide sufficient gas pressure (approx. 100 mm Hg) for growing the plants.

  16. Deficit irrigation for reducing agricultural water use.

    PubMed

    Fereres, Elias; Soriano, María Auxiliadora

    2007-01-01

    At present and more so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the norm rather than the exception, and irrigation management will shift from emphasizing production per unit area towards maximizing the production per unit of water consumed, the water productivity. To cope with scarce supplies, deficit irrigation, defined as the application of water below full crop-water requirements (evapotranspiration), is an important tool to achieve the goal of reducing irrigation water use. While deficit irrigation is widely practised over millions of hectares for a number of reasons - from inadequate network design to excessive irrigation expansion relative to catchment supplies - it has not received sufficient attention in research. Its use in reducing water consumption for biomass production, and for irrigation of annual and perennial crops is reviewed here. There is potential for improving water productivity in many field crops and there is sufficient information for defining the best deficit irrigation strategy for many situations. One conclusion is that the level of irrigation supply under deficit irrigation should be relatively high in most cases, one that permits achieving 60-100% of full evapotranspiration. Several cases on the successful use of regulated deficit irrigation (RDI) in fruit trees and vines are reviewed, showing that RDI not only increases water productivity, but also farmers' profits. Research linking the physiological basis of these responses to the design of RDI strategies is likely to have a significant impact in increasing its adoption in water-limited areas. PMID:17088360

  17. Integrated irrigation and drainage water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Results from several research projects conducted in the 1990's are summarized in this manuscript. The first projects are irrigation studies that evaluated the impact of pre-plant irrigation water on crop water use and deep percolation losses. The results showed significant losses with pre-plant ir...

  18. Mediterranean irrigation under climate change: more efficient irrigation needed to compensate increases in irrigation water requirements

    NASA Astrophysics Data System (ADS)

    Fader, M.; Shi, S.; von Bloh, W.; Bondeau, A.; Cramer, W.

    2015-08-01

    Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. This study systematically assesses how climate change and increases in atmospheric CO2 concentrations may affect irrigation requirements in the Mediterranean region by 2080-2090. Future demographic change and technological improvements in irrigation systems are accounted for, as is the spread of climate forcing, warming levels and potential realization of the CO2-fertilization effect. Vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL after a large development that comprised the improved representation of Mediterranean crops. At present the Mediterranean region could save 35 % of water by implementing more efficient irrigation and conveyance systems. Some countries like Syria, Egypt and Turkey have higher saving potentials than others. Currently some crops, especially sugar cane and agricultural trees, consume in average more irrigation water per hectare than annual crops. Different crops show different magnitude of changes in net irrigation requirements due to climate change, being the increases most pronounced in agricultural trees. The Mediterranean area as a whole might face an increase in gross irrigation requirements between 4 and 18 % from climate change alone if irrigation systems and conveyance are not improved (2 °C global warming combined with full CO2-fertilization effect, and 5 °C global warming combined with no CO2-fertilization effect, respectively). Population growth increases these numbers to 22 and 74 %, respectively, affecting mainly the Southern and Eastern Mediterranean. However, improved irrigation technologies and conveyance systems have large water saving potentials, especially in the Eastern Mediterranean, and may be able to compensate to some degree the increases due to climate change and

  19. Does deficit irrigation of field crops increase water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deficit irrigation is often proposed as a method to stretch limited irrigation water supply and increase water use efficiency. A field study of field crops in the high plains shows that water use efficiency, in terms of irrigation water applied, often increases with deficit irrigation. However, in t...

  20. Water use efficiency of irrigated cotton in Uzbekistan under drip and furrow irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton water use and water use efficiency as related to irrigation method and irrigation scheduling parameters are inadequately understood in the central Asian Republic of Uzbekistan. The main goal of this research was to measure cotton water use, and to determine irrigation water scheduling paramet...

  1. New soil water sensors for irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  3. WESTERN WATER LAWS AND IRRIGATION RETURN FLOW

    EPA Science Inventory

    The impact of water law allocation and use of waters within the Western United States is currently recognized as one of the major constraints to adaptation by irrigated agriculture of more efficient operation practices. This project provides a background of the law and evaluation...

  4. Assessing the Suitability of Water for Irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction Water quality assessment to evaluate the suitability of an irrigation water has traditionally (Ayers and Westcot, 1985) considered only salinity and SAR (sodium adsorption ratio). The criteria have been developed from a combination of field observations by experts and short duration co...

  5. An Assessment of Global Net Irrigation Water Requirements from Various Water Supply Sources to Sustain Irrigation

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Sayaka; Cho, Jail; Yamada, Hannah; Khajuria, Anupam; Hanasaki, Naota; Kanae, Shinjiro

    2014-05-01

    Water supply sources for irrigation, such as rivers, reservoirs, and groundwater, are critically important for agricultural productivity. The current rapid increase in irrigation water use threatens sustainable food production. In this study, we estimated the time-varying dependence of irrigation water requirements from water supply sources, with a particular focus on variations in irrigation area during the period 1960-2050 using the global water resources model, H08. The H08 model simulates water requirements on a daily basis at a resolution of 1.0° × 1.0° . The sources of irrigation water requirements in the past simulations were specified using four categories: rivers (RIV), large reservoirs (LR) with a storage capacity greater than 1.0 km3, medium-size reservoirs (MSR) with storage capacities ranging from 1.0 km3 to 3.0 M m3, and non-local non-renewable blue water (NNBW). We also estimated future irrigation water requirements from the above four water supply sources and an additional water supply source (ADD) in three future simulation designs; irrigation area change, climate change, and changes in both irrigation area and climate. ADD was defined as the difference between NNBW in the 1990s and NNBW in the 2040s, because it was difficult to distinguish the types of future water supply sources except for RIV. The simulated results showed that RIV, MSR, and NNBW increased significantly through the 1960s to the early 1990s globally, but LR increased at a relatively low rate. After the early 1990s, RIV approached a critical limit due to the continued expansion of the irrigation area. Furthermore, MSR and NNBW increased significantly following the expansion of the irrigation area and the increased storage capacity of the medium-size reservoirs. After the 2020s, MSR could be expected to approach the critical limit without the construction of medium-size reservoirs. ADD would account for 11-23% of the total requirements in the 2040s. We found that an expansion of

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  7. Effect of biofilm in irrigation pipes on the microbial quality of irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aim: To test the hypothesis that microbial quality of irrigation water can be substantially altered by the association of E. coli with pipe lining in irrigation systems. Methods and Results: The sprinkler irrigation system was outfitted with coupons that were extracted before four 2-hour long irri...

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

    NASA Astrophysics Data System (ADS)

    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.

  9. Weighing Lysimeters for Developing Crop Coefficients and Efficient Irrigation Practices for Vegetable Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large weighing lysimeters are expensive but invaluable tools for measuring crop evapotranspiration and developing crop coefficients for horticultural crops. Crop coefficients are used by both growers and researchers to estimate crop water use and accurately schedule irrigations. Two lysimeters of ...

  10. Sustaining Irrigated Agriculture In The Central High Plains With Limited Irrigation Water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing demands on limited water supplies will require maximizing crop production per unit water. Field studies are being carried out to develop water production functions for crops grown in the Great Plains. Irrigation water is applied through drip irrigation systems; precipitation and reference...

  11. Water conservation in irrigation can increase water use

    PubMed Central

    Ward, Frank A.; Pulido-Velazquez, Manuel

    2008-01-01

    Climate change, water supply limits, and continued population growth have intensified the search for measures to conserve water in irrigated agriculture, the world's largest water user. Policy measures that encourage adoption of water-conserving irrigation technologies are widely believed to make more water available for cities and the environment. However, little integrated analysis has been conducted to test this hypothesis. This article presents results of an integrated basin-scale analysis linking biophysical, hydrologic, agronomic, economic, policy, and institutional dimensions of the Upper Rio Grande Basin of North America. It analyzes a series of water conservation policies for their effect on water used in irrigation and on water conserved. In contrast to widely-held beliefs, our results show that water conservation subsidies are unlikely to reduce water use under conditions that occur in many river basins. Adoption of more efficient irrigation technologies reduces valuable return flows and limits aquifer recharge. Policies aimed at reducing water applications can actually increase water depletions. Achieving real water savings requires designing institutional, technical, and accounting measures that accurately track and economically reward reduced water depletions. Conservation programs that target reduced water diversions or applications provide no guarantee of saving water. PMID:19015510

  12. Quality assessment of irrigation water under a combination of rain and irrigation

    NASA Astrophysics Data System (ADS)

    Aparicio, Virginia; Costa, Jose Luis

    2015-04-01

    Complementary irrigation is one of the proposed management practices to increase the area under grain production mainly in the Humid Pampas. The most common source of irrigation water in the Humid Pampas comes from groundwater and is characterized by its high sodium bicarbonate content. However, the effect of the combination of irrigation and rain water on the chemical and physical properties of soils, especially when irrigation water comprises water with sodium bicarbonate, is still not well documented. The objective of the present study is to establish irrigation water suitability criteria under conditions of combined rain and irrigation. The trials were carried out on six irrigated plots and another five plots were chosen for validation purposes. Hydraulic conductivity and bulk density were measured in the field. Soil chemical analysis was performed on undisturbed soil samples. Supplementary irrigation using sodium bicarbonate water raises the soil electrical conductivity, the pH, exchangeable sodium percentage, soil sodium adsorption ratio and cation exchange capacity which produce an increase in bulk density, reducing the overall porosity of the soil. The effect of the soil sodium adsorption ratio on the soil hydraulic conductivity was evident when the soil sodium adsorption ratio levels were greater than 3.5. The dilution factor proposed in this study allows the classification of water for complementary irrigation linked to the management of irrigation.

  13. Managing runoff water quality from recently manured, furrow irrigated fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient losses in furrow irrigation runoff potentially increase when soils are amended with manure. We evaluated the effect of tillage, water soluble polyacrylamide (WSPAM) and irrigation management on runoff water quality during the first furrow irrigation on a calcareous silt loam soil, which had...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  15. Alternative disinfectant water treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternative disinfestant water treatments are disinfestants not as commonly used by the horticultural industry. Chlorine products that produce hypochlorous acid are the main disinfestants used for treating irrigation water. Chlorine dioxide will be the primary disinfestant discussed as an alternativ...

  16. Reducing irrigation water demand with cotton production in West Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to declining water availability from the Ogallala Aquifer and increasing pumping costs, irrigation management options for cotton are analyzed. The study concludes that supplemental irrigation while meeting crop evapotranspiration (ET) requirements is the most profitable option. Switching from co...

  17. Basic Horticulture.

    ERIC Educational Resources Information Center

    Geer, Barbra Farabough

    This learning packet contains teaching suggestions and student learning materials for a course in basic horticulture aimed at preparing students for employment in a number of horticulture areas. The packet includes nine sections and twenty instructional units. Following the standard format established for Oklahoma vocational education materials in…

  18. Quality requirements for irrigation with sewage water

    SciTech Connect

    Bouwer, H.; Idelovitch, E. )

    1987-11-01

    Irrigation is an excellent use for sewage effluent because it is mostly water with nutrients. For small flows, the effluent can be used on special, well-supervised sewage farms, where forage, fiber, or seed crops are grown that can be irrigated with standard primary or secondary effluent. Large-scale use of the effluent requires special treatment so that it meets the public health, agronomic, and aesthetic requirements for unrestricted use. Crops in the unrestricted-use category include those that are consumed raw or brought raw into the kitchen. Most state or government standards deal only with public health aspects, and prescribe the treatment processes or the quality parameters that the effluent must meet before it can be used to irrigate a certain category of crops. However, agronomic aspects related to crops and soils must also be taken into account. Quality parameters to be considered include bacteria, viruses, and other pathogens; total salt content and sodium adsorption ratio of the water; nitrogen; phosphorus; chloride and chlorine; bicarbonate; heavy metals, boron, and other trace elements; pH; and synthetic organics. 23 refs., 9 tabs.

  19. Development of Strategies for Sustainable Irrigation Water Management in Russia

    NASA Astrophysics Data System (ADS)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2013-04-01

    During 1960 - 1990 years irrigated areas in Russia have increased rapidly, helping to boost agricultural output. Although the impressive achievements of irrigation in this period its large experience indicates problems and failures of irrigation water management. In addition to large water use and low irrigation water efficiency, environmental concerns (excessive water depletion, water quality reduction, water logging, soil degradation) are usually considered like the most significant problem of the irrigation sector. Despite of considerable shrinking of irrigated areas in Russia and decreasing of water withdrawal for irrigation purposes during two last decades a degradation of environment as well as degradation of soil and water resources in irrigated areas was prolonged and will probably continue if current irrigation practices are maintained. Nowadays, in different regions of Russia there are societal demand to restore agricultural irrigation in Russia as answer to challenges from climate pattern changes and degradation of land & water resources. In the respect of these demands there is a need to develop strategies for sustainability of agricultural irrigation in Russia that should be based on three main societal objectives: costeffective use of water in irrigated agriculture at farm level, and satisfactory preserving the natural environment. Therefore sustainable irrigation water management is not only an objective at farm level but also an overall goal at the local and regional as well. A way to achieve sustainability in irrigation water management is to solve the local conflicts arising from the interactions between water use at irrigation areas and surrounding environment. Thus should be based on the development of irrigation framework program including on the irrigation water management issues, policies & decisions making at federal and regional levels should be based on the indicators of environment & irrigation water efficiency monitoring promoting the

  20. Assessment of drainage water quality in pre- and post-irrigation seasons for supplemental irrigation use.

    PubMed

    Alexakis, Dimitris; Gotsis, Dimitris; Giakoumakis, Spyros

    2012-08-01

    Knowledge on hydrochemistry is very important to assess the quality of water for effective management of water resources or drainage water reuse. On this basis, an assessment of water quality was conducted in the Agoulinitsa district in Peloponnese (western Greece). Both drainage and irrigation channel water samples have been collected, treated, and subjected to chemical analysis. A characterization has been carried out using the Piper-trilinear diagram. Assessment of the water samples from the point of view of sodium adsorption ratio, Na(+)%, and residual sodium carbonate indicated that 60.0% and 83.3% of the drainage water samples during pre- and post-irrigation season, respectively, as well as the irrigation channel water samples, are chemically suitable for irrigation use. Moreover, assessment of the water samples by comparing quality parameters with the Food and Agriculture Organization guidelines indicated that 20.0% and 44.4% of the drainage water samples collected during pre- and post-irrigation season, respectively, as well as the irrigation channel water samples could cause slight to moderate problems to the plants. On the other hand, 80.0% and 55.6% of the drainage water samples collected during pre- and post-irrigation season, respectively, could cause immediate development of severe problems to the plants growth. PMID:21915601

  1. Biofilms in irrigation pipes affect the microbial quality of irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation is an essential element in the production of many food crops. Irrigation water is often delivered to fields from surface or subsurface sources via pipe-based systems. Surface waters are known to contain pathogenic microorganisms. Disease outbreaks in crops that are eaten raw (i.e. leafy g...

  2. An overview of soil water sensors for salinity & irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation water management has to do with the appropriate application of water to soils, in terms of amounts, rates, and timing to satisfy crop water demands while protecting the soil and water resources from degradation. Accurate irrigation management is even more important in salt affected soils ...

  3. A multisector analysis of urban irrigation and water savings potential

    NASA Astrophysics Data System (ADS)

    Bijoor, N.; Kim, H.; Famiglietti, J. S.

    2014-12-01

    Urban irrigation strains limited water supplies in semi-arid areas such as Orange County, CA, yet the quantity and controlling factors of urban irrigation are not well understood. The goals of this research are to (1) quantify and compare landscape irrigation applied by residential and commercial sectors in various retail agencies at a parcel scale (2) determine over- and under-irrigation compared to theoretical need (3) determine the climatic and socioeconomic controls on landscape irrigation. A research partnership was established between six water retail agencies in Orange County, CA representing a wide range of climatic and economic conditions. These agencies contributed between 3 and 13 years of water use data on a monthly/bimonthly basis. Irrigation depth (mm) was estimated using the "minimum month method," and landscape evapotranspiration was calculated using the Hargreaves equation for 122,345 parcels. Multiple regressions of water use were conducted with climatic and socioeconomic variables as possible explanatory variables. Single family residences accounted for the majority of urban water use. Findings from 112,192 single family residences (SFRs) show that total and indoor water use declined, though irrigation did not significantly change. Average irrigation for SFRs was 94 L/day, and a large proportion (42%) of irrigation was applied in excess to landscapes. Air temperature was found to be the primary driver of irrigation. We mapped over-irrigation relative to plant water demand to highlight areas that can be targeted for water conservation efforts. We also show the water savings that would be gained by improving the efficiency of irrigation systems. The information gained in this study would be useful for developing water use efficiency policies and/or educational programs to promote sustainable irrigation practices at the individual parcel scale.

  4. Simulating Irrigation Requirements And Water Withdrawals: The Role Of Agricultural Irrigation In Basin Hydrology And Non-Sustainable Water Use

    NASA Astrophysics Data System (ADS)

    Wisser, D.; Douglas, E. M.; Schumann, A. H.; Vörösmarty, C. J.

    2006-05-01

    The development of irrigation can cause drastic alterations of the water cycle both through changed evaporation patterns, water abstractions, and (in the case of paddy rice), increased percolation rates. The interactions of irrigation development and large-scale water cycles have traditionally not been accounted for in macroscale hydrological models. We use a modified version an existing water balance model (the WBM model) to explicitly consider the effects of irrigation on regional and continental water cycles. The irrigation module is based on the FAO-CROPWAT approach and uses a daily soil moisture balance to simulate crop consumptive water use. Time series of irrigated areas and the distribution of crops and cropping patterns are derived from a combination of remotely sensed data and national and sub-national statistics. An assessment is made of (1) how irrigation water is supplied and (2) how much of this water is abstracted in excess of the renewable water supply in the basin considering different time horizons. Using different scenarios of water availability and irrigation water demand, the response of irrigation water use to water supply and the potential threats to food security are investigated. Case studies in a few river basins that are heavily influenced by irrigated agriculture and that represent different regions of the world will be presented.

  5. Mediterranean agriculture: More efficient irrigation needed to compensate increases in future irrigation water requirements

    NASA Astrophysics Data System (ADS)

    Fader, Marianela; Shi, Sinan; von Bloh, Werner; Bondeau, Alberte; Cramer, Wolfgang

    2016-04-01

    Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. Our research shows that, at present, Mediterranean region could save 35% of water by implementing more efficient irrigation and conveyance systems. Some countries like Syria, Egypt and Turkey have higher saving potentials than others. Currently some crops, especially sugar cane and agricultural trees, consume in average more irrigation water per hectare than annual crops (1). Also under climate change, more efficient irrigation is of vital importance for counteracting increases in irrigation water requirements. The Mediterranean area as a whole might face an increase in gross irrigation requirements between 4% and 18% from climate change alone by the end of the century if irrigation systems and conveyance are not improved. Population growth increases these numbers to 22% and 74%, respectively, affecting mainly the Southern and Eastern Mediterranean. However, improved irrigation technologies and conveyance systems have large water saving potentials, especially in the Eastern Mediterranean, and may be able to compensate to some degree the increases due to climate change and population growth. Both subregions would need around 35% more water than today if they could afford some degree of modernization of irrigation and conveyance systems and benefit from the CO2-fertilization effect (1). However, in some scenarios (in this case as combinations of climate change, irrigation technology, influence of population growth and CO2-fertilization effect) water scarcity may constrain the supply of the irrigation water needed in future in Algeria, Libya, Israel, Jordan, Lebanon, Syria, Serbia, Morocco, Tunisia and Spain (1). In this study, vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL ("Lund-Potsdam-Jena managed Land") after a

  6. Mediterranean irrigation under climate change: more efficient irrigation needed to compensate for increases in irrigation water requirements

    NASA Astrophysics Data System (ADS)

    Fader, M.; Shi, S.; von Bloh, W.; Bondeau, A.; Cramer, W.

    2016-03-01

    Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. This study systematically assesses how climate change and increases in atmospheric CO2 concentrations may affect irrigation requirements in the Mediterranean region by 2080-2090. Future demographic change and technological improvements in irrigation systems are taken into account, as is the spread of climate forcing, warming levels and potential realization of the CO2-fertilization effect. Vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL (Lund-Potsdam-Jena managed Land) after an extensive development that comprised the improved representation of Mediterranean crops. At present the Mediterranean region could save 35 % of water by implementing more efficient irrigation and conveyance systems. Some countries such as Syria, Egypt and Turkey have a higher savings potential than others. Currently some crops, especially sugar cane and agricultural trees, consume on average more irrigation water per hectare than annual crops. Different crops show different magnitudes of changes in net irrigation requirements due to climate change, the increases being most pronounced in agricultural trees. The Mediterranean area as a whole may face an increase in gross irrigation requirements between 4 and 18 % from climate change alone if irrigation systems and conveyance are not improved (4 and 18 % with 2 °C global warming combined with the full CO2-fertilization effect and 5 °C global warming combined with no CO2-fertilization effect, respectively). Population growth increases these numbers to 22 and 74 %, respectively, affecting mainly the southern and eastern Mediterranean. However, improved irrigation technologies and conveyance systems have a large water saving potential, especially in the eastern Mediterranean, and may be able to

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

    NASA Astrophysics Data System (ADS)

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

    2015-07-01

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

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

    PubMed

    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. PMID:23379125

  9. How to save water by choice of irrigation application method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is known that irrigation application method can impact crop water use and water use efficiency, but the mechanisms involved are incompletely understood, particularly in terms of the water and energy balances during the growing season from pre-irrigation through planting, early growth and yield de...

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  11. [Optimal allocation of irrigation water resources based on systematical strategy].

    PubMed

    Cheng, Shuai; Zhang, Shu-qing

    2015-01-01

    With the development of the society and economy, as well as the rapid increase of population, more and more water is needed by human, which intensified the shortage of water resources. The scarcity of water resources and growing competition of water in different water use sectors reduce water availability for irrigation, so it is significant to plan and manage irrigation water resources scientifically and reasonably for improving water use efficiency (WUE) and ensuring food security. Many investigations indicate that WUE can be increased by optimization of water use. However, present studies focused primarily on a particular aspect or scale, which lack systematic analysis on the problem of irrigation water allocation. By summarizing previous related studies, especially those based on intelligent algorithms, this article proposed a multi-level, multi-scale framework for allocating irrigation water, and illustrated the basic theory of each component of the framework. Systematical strategy of optimal irrigation water allocation can not only control the total volume of irrigation water on the time scale, but also reduce water loss on the spatial scale. It could provide scientific basis and technical support for improving the irrigation water management level and ensuring the food security. PMID:25985685

  12. Role of irrigation and irrigation automation in improving crop water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In arid climates, irrigation is required for significant agricultural production. In subhumid and semiarid climates, supplemental irrigation is recognized as both economically necessary (prevention of crop losses in periodic droughts) and as a means to improve overall crop water use effi...

  13. The optimal joint provision of water for irrigation and hydropower

    SciTech Connect

    Chatterjee, B.; Howitt, R.E.; Sexton, R.J.

    1998-11-01

    This study develops a dynamic optimization model to analyze the intertemporal allocation of surface water for irrigation and for hydropower production in the western United States. The issue arises because peak irrigation demands may not coincide with periods of peak demand for power. Water released for irrigation in the spring reduces the reservoir head and diminishes the capacity to generate power during summer peak demands. The optimization model is applied to irrigation districts in central California. Results show considerable deviation between the actual and the optimal allocations. Suboptimal behavior is linked to the districts` failure to articulate clear property rights to the scarce water resources.

  14. Comparison of soil water sensing methods for irrigation management and research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As irrigation water resources decrease and deficit irrigation becomes more common across the Great Plains, greater accuracy in irrigation scheduling will be required. Researchers investigating deficit irrigation practices and developing management practices must also have accurate measures of soil w...

  15. Spatial dynamics of water management in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Muralidharan, Daya; Knapp, Keith C.

    2009-05-01

    Irrigated agriculture provides 40% of worldwide food supplies but uses large amounts of scarce freshwater and contributes to environmental degradation. At the very core of this problem lie decisions made by irrigators subject to biophysical relations. This research develops a microeconomic model of irrigation management taking into account the dynamics of plant growth over the season, spatial variability in infiltration of applied irrigation water, and fundamental principles from subsurface hydrology. The analysis shows that spatial variability in water infiltration common to traditional irrigation systems increases both applied irrigation water and deep percolation flows by very substantial amounts compared to uniform infiltration. The analysis demonstrates that efficient irrigation management can significantly reduce both applied water and deep percolation at relatively low costs, at least up to a certain level. A long-run analysis of optimal irrigation systems including capital costs indicates that traditional furrow systems are economically efficient over a wide range of water prices and deep percolation costs. Overall, the results indicate that optimal irrigation management can achieve significant resource conservation and pollution control with low loss in agricultural net benefits and without land retirement, investment in capital-intensive systems, or crop switching.

  16. Consumptive Water Use and Crop Coefficients of Irrigated Sunflower

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In semi-arid environments, the use of irrigation is necessary for sunflower production to reach its maximum potential. The aim of this study was to quantify the consumptive water use and crop coefficients of irrigated sunflower (Helianthus annuus L.) without soil water limitations during two growing...

  17. Site-specific sprinkler irrigation in a water limited future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Available water supplies for irrigation are becoming more and more limited in the western USA and other locations around the world, and this trend is accelerating. This will force major changes to physical and managerial aspects as well as design of water delivery and on-farm irrigation systems. Th...

  18. Using models to determine irrigation applications for water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Simple models are used by field researchers and production agriculture to estimate crop water use for the purpose of scheduling irrigation applications. These are generally based on a simple volume balance approach based on estimates of soil water holding capacity, irrigation application amounts, pr...

  19. Site-Specific Sprinkler Irrigation in a Water Limited Future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Available water supplies for irrigation are becoming more and more limited in the western USA and other locations around the world, and this trend is accelerating. This will force major changes to physical and managerial aspects as well as design of water delivery and on-farm irrigation systems. Th...

  20. Institutional aspects of proportional water allocation in practice: case of the Odzani River Irrigation Company, Save Catchment, Zimbabwe

    NASA Astrophysics Data System (ADS)

    Senzanje, A.; van der Zaag, P.

    Under the new Water Act [Government of Zimbabwe, 1998. Water Act, Chapter 20:24, No. 31/98. Government Printers, Harare] of Zimbabwe which abolished the priority date system for the allocation of surface water in a catchment, it is widely believed that the alternative will be the proportional water allocation system. The proportional water allocation system has been practiced by groups of water users in a number of sub-catchments in Zimbabwe including Mupfuri, Mazowe and Odzi River systems, mainly in the form of dam syndicates (groups of users jointly owning a dam) and irrigation companies (groups of irrigators sharing one source of water). This paper presents the practical experiences with, and lessons that can be learnt from proportional water allocation in the Odzani River Irrigation Company (ORIC) on the Odzi River system in Manicaland in Zimbabwe. ORIC was formed under the provisions of the old Water Act after the construction of the canal, and currently has 50 irrigating members. They are engaged in a variety of agricultural enterprises that include crop production, horticulture and dairying. All members have sub-permits (sub-rights) that enable them to draw water, but the company has a single permit to abstract water from the Odzi River into their supply canal. Farmers’ perception and understanding of proportional water allocation varied but generally defined it as getting a certain percentage of water depending on the amount available in the canal and one’s water permit. One of the major sources of problems in ORIC is inequitable access to water arising from water poaching. Overall, ORIC farmers felt that for proportional water allocation to work properly, the services of a fulltime water bailiff are required, farmers must have their own storage facilities, water should be metered, members should participate fully in decision making, politics should be kept to a minimum and conflicts must be resolved internally.

  1. Energy requirements in pressure irrigation systems

    NASA Astrophysics Data System (ADS)

    Sánchez, R.; Rodríguez-Sinobas, L.; Juana, L.; Laguna, F. V.; Castañón, G.; Gil, M.; Benítez, J.

    2012-04-01

    Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure -sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems and their management possibilities. The work includes all processes involved from the diversion of water into irrigation specific infrastructure to water discharge by the emitters installed on the crop fields. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. It has been applied to extensive and intensive crop systems, such us extensive winter crops, summer crops and olive trees, fruit trees and vineyards and intensive horticulture in greenhouses. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity.

  2. Pilot study of the effect of biofilms in irrigation pipes on the microbial water quality of irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation is an essential element in the production of many food crops. Irrigation water is often delivered to fields from surface or subsurface sources via pipe-based systems. Surface waters are known to contain pathogenic microorganisms. Disease outbreaks in crops that are eaten raw (i.e. leafy g...

  3. Effect of irrigation amounts applied with subsurface drip irrigation on corn evapotranspiration, yield, water use efficiency, and dry matter production in a semiarid climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantifying the local crop response to irrigation is important for establishing adequate irrigation management strategies. This study evaluated the effect of irrigation applied with subsurface drip irrigation on field corn (Zea mays L.) evapotranspiration (ETc), yield, water use efficiencies (WUE = ...

  4. Ornamental Horticulture.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

    Each of the 32 curriculum modules in this packet for ornamental horticulture instruction contains a brief description of the module content, a list of the major division or units, the overall objectives, objectives by units, content outline and suggested teaching methods, student application activities, and evaluation procedures. A listing of…

  5. Heartland Horticulture

    ERIC Educational Resources Information Center

    Poquette, Bonnie L.

    2009-01-01

    Midwestern gardeners are legendary for enduring and outwitting winter, with its heavy snowpack and recurring freezes and thaws. Most of them also reckon with a relatively short growing period. All of them find their horticultural plans complicated by hot, humid summers. In fact, the Midwest deals with four seasons dictating special considerations…

  6. Chapter 24. emerging technologies for irrigation water treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several disinfestants that have potential for treating recycled irrigation water are less commonly used or newer developing technologies. Hydrogen peroxide can reduce spread of pathogens in water that contains nutrients or pesticide residues without generating toxic residues. Benefits potentially in...

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

    USGS Publications Warehouse

    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

  8. Water use dynamics of peach trees under postharvest deficit irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Postharvest deficit irrigation is a potential strategy for conserving valuable fresh water for production of early season tree fruit crops such as peaches. However, behaviors of evapotranspiration characteristics and crop coefficient (Kc) under deficit irrigation conditions are largely unknown. A th...

  9. Scheme of water saving irrigation in autumn based on SHAW model in Inner Mongolia Hetao Irrigation District

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In accordance with the prevention of soil salination and water-saving irrigation in autumn in Inner Mongolia Hetao irrigation district, the reasonable water-saving irrigation scheme in autumn was quantified by using SHAW model for the different salinized soils. For slightly salinized soils, autumn i...

  10. Water savings and improved yield stability for irrigated and non-irrigated cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Southeast U.S. receives 130 cm of annual rainfall, however cotton production is still limited by water. Irrigation, when available, is used to supplement natural precipitation to sustain profitable crop production. Increased water capture would improve water use efficiency and reduce irrigatio...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  12. Using soil water sensors to improve irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  14. Crop water stress indices correlated with soil water storage: Implications for variable rate irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil water sensing methods are now coming to be used for irrigation scheduling of whole fields. However, newly introduced variable rate irrigation (VRI) systems require information about soil water content in many areas of a field, each called an irrigation management zone. Commonly available soil w...

  15. Elderberry: Botany, Horticulture, Potential

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Horticultural Review allows extensive reviews of the state of the knowledge on certain topics or crops. Elderberry: Botany, Horticulture, Potential, is outlined with an Introduction, Botany, Horticulture, Propagation, Uses and Conclusion sections. This review compiles literature from around the w...

  16. Irrigation with desalinated water: A step toward increasing water saving and crop yields

    NASA Astrophysics Data System (ADS)

    Silber, Avner; Israeli, Yair; Elingold, Idan; Levi, Menashe; Levkovitch, Irit; Russo, David; Assouline, Shmuel

    2015-01-01

    We examined the impact of two different approaches to managing irrigation water salinity: salt leaching from the field ("conventional" management) and water desalination before field application ("alternative" management). Freshwater commonly used for irrigation (FW) and desalinated water (DS) were applied to the high-water-demanding crop banana at four different rates. Both irrigation rate and water salinity significantly affected yield. DS application consistently produced higher yields than FW, independently of irrigation rate. The highest yield for FW-irrigation was achieved with the highest irrigation rate, whereas the same yield was obtained in the case of DS-irrigation with practically half the amount of water. Yield decreased with FW-irrigation, even when the water salinity, ECi, was lower than the limit considered safe for soil and crops. Irrigating with FW provided a massive amount of salt which accumulated in the rhizosphere, inducing increased osmotic potential of the soil solution and impairing plant water uptake. Furthermore, applying the "conventional" management, a significant amount of salt is leached from the rhizosphere, accumulating in deeper soil layers, and eventually reaching groundwater reservoirs, thus contributing to the deterioration of both soil and water quality. Removal of salt excess from the water before it reaches the field by means of DS-irrigation may save significant amounts of irrigation water by reducing the salt leaching requirements while increasing yield and improving fruit quality, and decreasing salt load in the groundwater.

  17. Effects of harvest date, irrigation level, cultivar type and fruit water content on olive mill wastewater generated by a laboratory scale 'Abencor' milling system.

    PubMed

    Aviani, I; Raviv, M; Hadar, Y; Saadi, I; Dag, A; Ben-Gal, A; Yermiyahu, U; Zipori, I; Laor, Y

    2012-03-01

    Olive mill wastewaters (OMW) were obtained at laboratory scale by milling olives from four cultivars grown at different irrigation levels and harvested at different times. Samples were compared based on wastewater quantity, pH, suspended matter, salinity, organic load, total phenols, NPK, and phytotoxicity. Principal component analysis discriminated between harvest times, regardless of olive cultivar, indicating substantial influence of fruit ripeness on OMW characteristics. OMW properties were affected both by the composition and the extraction efficiency of fruit water. As the fruit water content increased, the concentrations of solutes in the fruit water decreased, but the original fruit water composed a larger portion of the total wastewater volume. These contradicting effects resulted in lack of correlation between fruit water content and OMW properties. The significant effects shown for fruit ripeness, irrigation and cultivar on OMW characteristics indicate that olive horticultural conditions should be considered in future OMW management. PMID:22226593

  18. Salinity control on irrigated land and use of saline water for irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current irrigation practices in arid and semi-arid regions throughout the world are not sustainable. These regions are experiencing increasing population and development with increasing demands for limited fresh water for municipal and industrial use. In arid areas fresh water use is currently alrea...

  19. Comparative Assessment of Irrigation Water Quality in Sri Lanka's Tank-Cascade and Mahaweli Irrigation Schemes

    NASA Astrophysics Data System (ADS)

    Gunda, T.; Hornberger, G. M.

    2013-12-01

    Two distinct irrigation systems dominate the landscape in the dry zone of Sri Lanka. The tank-cascade system, which originates from third century BC, is a small-scale system that has been the traditional method for communities to meet their farming water needs. The Mahaweli reservoir system, in contrast, is a large-scale irrigation scheme initiated in the 1970s that diverts water across hundreds of kilometers from the headwaters of the Mahaweli River to farmers. Although approximately equal amounts of paddy land are irrigated under these two systems, very little comparative analysis has been conducted on the spatial variation of irrigation water quality in Sri Lanka. An exploratory study was conducted in June 2013 in Anuradhapura district, an area that experiences the highest level of paddy production instability and has had long-standing irrigation water quality issues. A total of 30 water samples from both cascade systems and Mahaweli system H-7 were analyzed for pH, temperature, conductivity, turbidity, and chromatic dissolved organic matter using field instruments. A subset of these samples was further analyzed for nitrate and ammonia using colorimetric methods. While the sparse data from our study revealed some interesting trends, it is difficult to extrapolate in detail. Therefore, we compare inferences drawn about the Sri Lanka data to a more detailed analysis of chromatic dissolved organic matter in a Tennessee watershed. This comparison will provide insight into possible interpretations relative to the water quality data collected in Sri Lanka. As Sri Lanka continues to develop its irrigation resources, water quality assessments such as this one are critical for identifying factors limiting paddy production in the country.

  20. Drip irrigation management in different chufa planting strategies: yield and irrigation water use efficiency

    NASA Astrophysics Data System (ADS)

    Pascual-Seva, Nuria; San Bautista, Alberto; López-Galarza, Salvador; Maroto, José Vicente; Pascual, Bernardo

    2013-04-01

    In a study presented in the EGU assembly 2012, it was analysed how yield and irrigation water use efficiency (IWUE) in chufa (Cyperus esculentus L. var. sativus), crop, were affected by planting strategy (ridges and flat raised beds, with two and three plant rows along them) and irrigation system [furrow (FI) and drip irrigation (DI)]. Each irrigation session started when the Volumetric Soil Water Content (VSWC) in ridges dropped to 80% of field capacity; beds were irrigated simultaneously with ridges and with the same irrigation duration. R produced lower yield than the two types of beds, and yields in DI were higher than those FI. Ridges led to the highest IWUE with DI, and to the lowest with FI. Then, it was decided to analyse, in DI, how yield and IWUE responded to start each irrigation session when the VSWC in the central point of different planting strategies [ridges (R), and flat raised beds with two (b) and three (B) plant rows along them] dropped to 80% of field capacity. In R and b, plants were irrigated by a single dripline per plant row, while in B two irrigation layouts were assayed: a single dripline per plant row (B3) and two driplines per bed (B2), placing each dripline between two planting rows. Irrigation session stop was also automated as a function of the VSWC. Results show that yield was affected (P˜0.01) by planting strategy; the greatest yield was obtained in b (2.4 kgm-2), differing (P˜0.05) from that obtained in R (2.1 kgm-2), with intermediate yields in B2 (2.3 kgm-2) and B3 (2.3 kgm-2). Yield was not affected (P˜0.05) by the utilisation of two or three driplines in B. Considerably less irrigation water was applied (IWA) in R (376 mm) than in B3 (465 mm), B2 (475 mm) and b (502 mm). This automatic irrigation management, as a function of the VSWC in each planting strategy, lead to adjust the IWA to the plant water requirements, which were similar in all three flat raised beds, since they correspond to the same planting density, that was

  1. Water savings potentials of irrigation systems: dynamic global simulation

    NASA Astrophysics Data System (ADS)

    Jägermeyr, J.; Gerten, D.; Heinke, J.; Schaphoff, S.; Kummu, M.; Lucht, W.

    2015-04-01

    Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatio-temporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of global agricultural water use, and of water saving and water productivity potentials constrained by biophysical processes and also non-trivial downstream effects, we incorporated a dynamic representation of the three major irrigation systems (surface, sprinkler, and drip) into a process-based bio- and agrosphere model, LPJmL. Based on this enhanced model we provide a gridded worldmap of dynamically retrieved irrigation efficiencies reflecting differences in system types, crop types, climatic and hydrologic conditions, and overall crop management. We find pronounced regional patterns in beneficial irrigation efficiency (a refined irrigation efficiency indicator accounting for crop-productive water consumption only), due to differences in these features, with lowest values (< 30%) in South Asia and Sub-Saharan Africa and highest values (> 60%) in Europe and North America. We arrive at an estimate of global irrigation water withdrawal of 2396 km3 (2004-2009 average); irrigation water consumption is calculated to be 1212 km3, of which 511 km3 are non-beneficially consumed, i.e. lost through evaporation, interception, and conveyance. Replacing surface systems by sprinkler or drip systems could, on average across the world's river basins, reduce the non-beneficial consumption at river basin level by 54 and 76%, respectively, while maintaining the current level of crop yields. Accordingly, crop water productivity would increase by 9 and 15%, respectively, and by much more in specific regions such as in the Indus basin. This study significantly advances the global quantification of

  2. Introduction to Horticulture. Teacher Edition. Horticulture Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This publication is designed to provide a core of instruction for the many different fields in agricultural/horticultural education. This course contains 21 instructional units that cover the following topics: introduction to horticulture; beginning a career in horticulture; hand and power tools; introduction to safety; growing facilities;…

  3. Results from a 3-year deficit irrigation experiment with drip-irrigated maize to improve water productivity

    NASA Astrophysics Data System (ADS)

    Kloss, Sebastian; Schütze, Niels; Grundmann, Jens

    2013-04-01

    Water for irrigation farming is severely limited in arid and semi-arid regions, hence reliable and robust strategies are needed that allow to use the available resources efficiently. Controlled deficit irrigation (DI) is one strategy that can help to use water in an effective way while still ensuring considerable yields from harvest. It needs precise irrigation control however where sensors are used to determine when to irrigate. Therefore, thresholds that trigger irrigation need to be chosen carefully. An irrigation experiment with drip-irrigated maize was conducted in three consecutive years (2010-2012) where different controlled DI strategies were tested. The experiments took place in a greenhouse at TU München in Freising, Germany, and comprised treatments with constant and varying irrigation thresholds throughout the growing season, which were compared to fully irrigated reference treatments. Thresholds were determined in soil tension as it is closely related to the working principle behind plant transpiration and treatments evaluated with regard to their water productivity (WP - yield over applied irrigation water). The irrigation thresholds were determined prior to the experiment by a stochastic simulation-based framework that consisted of a weather generator, the crop growth model Daisy, and an optimization algorithm for finding optimal thresholds under limiting water supply. Achieved results show similar or better WP compared to the reference and generally high WP compared to values from literature which suggests this methodology is a promising approach to improve WP.

  4. Maximizing grain sorghum water use efficiency under deficit irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development and evaluation of sustainable and efficient irrigation strategies is a priority for producers faced with water shortages resulting from aquifer depletion, reduced base flows, and reallocation of water to non-agricultural sectors. Under a limited water supply, yield maximization may not b...

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

    NASA Astrophysics Data System (ADS)

    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

  6. Forecast of irrigation water demand considering multiple factors

    NASA Astrophysics Data System (ADS)

    Wang, X.; Lei, X.; Guo, X.; You, J.; Wang, H.

    2015-05-01

    Many factors influence irrigation water requirement on the basin scale, which make it difficult to obtain comprehensive data. Despite the advantage of less needing historical data, the prediction precision of traditional trend prediction methods is hard to guarantee. For water scarce basins, the artificial influence on irrigation requirement should be thought of as important impact factors. In this paper, the PCA (principal component analysis) method is used to identify the main influencing factors, such as precipitation, irrigation area, water saving technology and so on. Based on that, an irrigation water demand prediction model considering multiple factors is developed for water shortage regions. The method is applied in the Haihe River basin as an example. The study results show that the irrigation water demand forecasting method considering multiple factors in this paper can achieve higher modelling accuracy, compared with the traditional trend prediction method and the method that does not consider the human influence. In view of the small average relative error, 1.32%, it has good values for application.

  7. Irrigation response and water productivity of deficit to fully irrigated spring camelina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Camelina [Camelina sativa L. Crantz] is an oil seed crop that could be adapted to the northern High Plains of the USA as a biofuel crop. Decreased ground water allocations in Nebraska necessitated determining the impact of limited irrigation on camelina. The objective of this research was to determi...

  8. Yield, irrigation response, and water productivity of deficit to fully irrigated spring canola

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canola (Brassica napus) is an oil-seed crop that is adapted to the northern High Plains of the USA and is considered a viable rotational and biofuel crop. However, decreased ground water allocations have necessitated determining the impact of limited irrigation on canola productivity. The objectives...

  9. Irrigation infrastructure and water appropriation rules for food security

    NASA Astrophysics Data System (ADS)

    Gohar, Abdelaziz A.; Amer, Saud A.; Ward, Frank A.

    2015-01-01

    In the developing world's irrigated areas, water management and planning is often motivated by the need for lasting food security. Two important policy measures to address this need are improving the flexibility of water appropriation rules and developing irrigation storage infrastructure. Little research to date has investigated the performance of these two policy measures in a single analysis while maintaining a basin wide water balance. This paper examines impacts of storage capacity and water appropriation rules on total economic welfare in irrigated agriculture, while maintaining a water balance. The application is to a river basin in northern Afghanistan. A constrained optimization framework is developed to examine economic consequences on food security and farm income resulting from each policy measure. Results show that significant improvements in both policy aims can be achieved through expanding existing storage capacity to capture up to 150 percent of long-term average annual water supplies when added capacity is combined with either a proportional sharing of water shortages or unrestricted water trading. An important contribution of the paper is to show how the benefits of storage and a changed water appropriation system operate under a variable climate. Results show that the hardship of droughts can be substantially lessened, with the largest rewards taking place in the most difficult periods. Findings provide a comprehensive framework for addressing future water scarcity, rural livelihoods, and food security in the developing world's irrigated regions.

  10. Characteristics of dissolved carbon change in irrigation water

    NASA Astrophysics Data System (ADS)

    Akaike, Y.; Kunishio, A.; Kawamoto, Y.; Murakami, H.; Iwata, T.

    2012-12-01

    It is necessary to estimate carbon emission from soil for understanding carbon cycle processes in cultivated fields. Since irrigation water is introduced into a typical rice paddy field, one part of emitted carbon content from soil were trapped by water and dissolved in it, and dissolved carbon content outflows from the field at the drainage moment. In this study, we continuously and regularly analyzed dissolved carbon content of irrigation water and investigated seasonal variation of efflux of carbon from a paddy field. Experimental site is located reclaimed land in the southern part of Okayama Prefecture, Japan. And rice cropping cultivation has continued in a similar method every year. Intermittent irrigation water managements, or 3 days flooded and 4 days drained condition, were carried out during almost all the period of rice cultivated term. Irrigation water was sampled every flooding and drainage days. Inorganic carbon (IC) concentration was measured with total carbon (TC) analyzer (TOC-V/CSH, SHIMAZU). Amount of dissolved carbon in irrigation water was calculated from product of the carbon concentration and water levels. The experimental paddy field was divided into two areas, and two bottle of water were sampled from each area. In order to investigate what impact is brought on the annual carbon cycle by the difference of disposal management of residual biomass after the harvest, residual biomass was burned and plowed into soil at the one area on 29th Nov., 2011, and residue was not burned and directly plowed into soil at the other area as usual. IC during cultivated term in 2011 and 2012 in both area gradually increased day by day for every flooded periods. And IC showed distinct diurnal variations with lower value in the daytime than at night, it is because of photosynthetic activities by aquatic algae in the irrigation water.

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

    USGS Publications Warehouse

    Constantz, J.

    1989-01-01

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

  12. Predicting Crop Water Use from Ground Cover and Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scheduling irrigations for horticultural crops with evapotranspiration calculations is difficult. Horticultural crops are grown under a wide range of cultural practices and conditions, making it difficult to select appropriate crop coefficients. A primary determinant of crop water use is light in...

  13. Site-specific variable rate irrigation a means to enhance water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The majority of irrigated cropland in the US is watered with sprinkler irrigation systems. These systems are inherently more efficient in distributing water than furrow or flood irrigation. Appropriate system design of sprinkler irrigation equipment, application methods, and farming practices (e.g. ...

  14. Deficit irrigation of peach trees to reduce water consumption

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of water is a major limiting factor for production tree fruits such as peaches in the San Joaquin Valley of California and many other arid- or semi-arid regions in the world. Deficit irrigation can be used in some cropping systems as a water resource management strategy to reduce non-productiv...

  15. Soil properties evolution after irrigation with reclaimed water

    NASA Astrophysics Data System (ADS)

    Leal, M.; González-Naranjo, V.; de Miguel, A.; Martínez-Hernández, V.; Lillo, J.

    2012-04-01

    Many arid and semi-arid countries are forced to look for new and alternative water sources. The availability of suitable quality water for agriculture in these regions often is threatened. In this context of water scarcity, the reuse of treated wastewater for crop irrigation could represent a feasible solution. Through rigorous planning and management, irrigation with reclaimed water presents some advantages such as saving freshwater, reducing wastewater discharges into freshwater bodies and decreasing the amount of added fertilizers due to the extra supply of nutrients by reclaimed water. The current study, which involves wastewater reuse in agriculture, has been carried out in the Experimental Plant of Carrión de los Céspedes (Sevile, Spain). Here, two survey parcels equally designed have been cultivated with Jatropha curcas L, a bioenergetic plant and a non-interfering food security crop. The only difference between the two parcels lies on the irrigation water quality: one is irrigated with groundwater and another one with reclaimed water. The main aim of this study focuses on analysing the outstanding differences in soil properties derived from irrigation with two water qualities, due to their implications for plant growth. To control and monitor the soil variables, soil samples were collected before and after irrigation in the two parcels. pH, electrical conductivity, cation exchange capacity, exchangeable cations (Ca2+, Mg2+, Na+ and K+), kjeldahl nitrogen, organic matter content and nutrients (boron, phosphorus, nitrogen, potassium) were measured. Data were statistically analyzed using the R package. To evaluate the variance ANOVA test was used and to obtain the relations between water quality and soil parameters, Pearson correlation coefficient was computed. According to other authors, a decrease in the organic matter content and an increase of parameters such as pH, electrical conductivity and some exchangeable cations were expected. To date and after

  16. Water quality criteria for use of saline/degraded water for irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current fresh water use in arid and semiarid lands is not sustainable, as use exceeds replenishment and demand for water continues to increase. Agriculture will either need to reduce acreage under irrigation, which is undesirable since it will reduce food supply, or irrigate with alternative water s...

  17. Water temperature in irrigation return flow from the Upper Snake Rock watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water returning to a river from an irrigated watershed could increase the water temperature in the river. The objective of this study was to compare the temperature of irrigation return flow water with the temperature of the diverted irrigation water. Water temperature was measured weekly in the mai...

  18. The impacts of climate change on global irrigation water requirements

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Cai, X.

    2011-12-01

    Climate change tends to affect the irrigation water requirement of current irrigated agricultural land, and also changes the water availability for current rain-fed land by the end of this century. We use the most up-to-date climatic and crop datasets (e.g., global irrigated/rain-fed crop areas and grid level crop growing calendar (Portmann, Siebert and Döll, 2010, Global Biogeochemical Cycles 24)) to evaluate the requirements of currently irrigated land and the water deficit for rain-fed land for all major crops under current and projected climate. Six general circulation models (GCMs) under two emission scenarios, A1B & B1, are assembled using two methods, the Simple Average Method (SAM) and Root Mean Square Error Ensemble Method (RMSEMM), to deal with the GCM regional variability. It is found that the global irrigation requirement and the water deficit are both going to increase significantly under all scenarios, particularly under the A1B emission scenario. For example, the projected irrigation requirement is expected to increase by about 2500 million m3 for wheat, 3200 million m3 for maize and another 3300 million m3 for rice. At the same time, the water deficit for current rain-fed cropland will be widened by around 3000, 4000, 2100 million m3 for wheat, maize and rice respectively. Regional analysis is conducted for Africa, China, Europe, India, South America and the United States. It is found that the U.S. may expect the greatest rise in irrigation requirements for wheat and maize, while the South America may suffer the greatest increase for rice. In addition, Africa and the U.S. may face a larger water deficit for both wheat and maize on rain-fed land, and South America just for rice. In summary, climate change is likely to bring severe challenges for irrigation systems and make global water shortage even worse by the end of this century. These pressures will call for extensive adaptation measures. The change in crop water requirements and availability

  19. Conjunctive use of water resources for sustainable irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Singh, Ajay

    2014-11-01

    The continuous increase in global population and simultaneous decrease in good quality water resources emphasizes the need of using surface water and groundwater resources conjunctively for irrigation. The conjunctive use allows the utilization of poor quality water, which cannot be used as such for the crop production due to its harmful effect on soil and crop health. This paper presents an overview on issues and methods of the conjunctive use of surface water and groundwater resources for sustainable irrigated agriculture. The background of the conjunctive water use and its applications for the management of poor quality water and management of rising watertable are presented. The management of conjunctive water use through the computer-based models is also covered in this review. The advantages and disadvantages of the approach have been described. Conclusions are provided based on this review which could be useful for all the stakeholders.

  20. Potential perchlorate exposure from Citrus sp. irrigated with contaminated water.

    PubMed

    Sanchez, C A; Krieger, R I; Khandaker, N R; Valentin-Blasini, L; Blount, B C

    2006-05-10

    Citrus produced in the southwestern United States is often irrigated with perchlorate-contaminated water. This irrigation water includes Colorado River water which is contaminated with perchlorate from a manufacturing plant previously located near the Las Vegas Wash, and ground water from wells in Riverside and San Bernardino counties of California which are affected by a perchlorate plume associated with an aerospace facility once located near Redlands, California. Studies were conducted to evaluate the uptake and distribution of perchlorate in citrus irrigated with contaminated water, and estimate potential human exposure to perchlorate from the various citrus types including lemon (Citrus limon), grapefruit (Citrus paradise), and orange (Citrus sinensis) produced in the region. Perchlorate concentrations ranged from less than 2-9 microg/L for Colorado River water and from below detection to approximately 18 microg/L for water samples from wells used to irrigate citrus. Destructive sampling of lemon trees produced with Colorado River water show perchlorate concentrations larger in the leaves (1835 microg/kg dry weight (dw)) followed by the fruit (128 microg/kg dw). Mean perchlorate concentrations in roots, trunk, and branches were all less than 30 microg/kg dw. Fruit pulp analyzed in the survey show perchlorate concentrations ranged from below detection limit to 38 microg/kg fresh weight (fw), and were related to the perchlorate concentration of irrigation water. Mean hypothetical exposures (mug/person/day) of children and adults from lemons (0.005 and 0.009), grapefruit (0.03 and 0.24), and oranges (0.51 and 1.20) were estimated. These data show that potential perchlorate exposures from citrus in the southwestern United States are negligible relative to the reference dose recommended by the National Academy of Sciences. PMID:17723376

  1. Estimated Colorado Golf Course Irrigation Water Use, 2005

    USGS Publications Warehouse

    Ivahnenko, Tamara

    2009-01-01

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

  2. Agricultural practices and irrigation water demand in Uttar Pradesh

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    Changes in farming practices within Uttar Pradesh, particularly advances in irrigation technology, have led to a significant drop in water tables across the region. While the acquisition of monitoring data in India is a challenge, current water use practices point towards water overdraught. This is exacerbated by government and state policies and practices, including the subsidising of electricity, seeds and fertilizer, and an agreement to buy all crops grown, promoting the over use of water resources. Taking India's predicted population growth, increases in industrialisation and climate change into account, both farmland and the water resources it depends upon will be subject to increased pressures in the future. This research is centred around irrigation demands on water resources within Uttar Pradesh, and in particular, quantifying those demands both spatially and temporally. Two aspects of this will be presented; the quantification of irrigation water applied and the characterisation of the spatial heterogeneity of water use practices. Calculating the volumes of applied irrigation water in the absence of observed data presents a major challenge and is achieved here through the use of crop models. Regional crop yields provided by statistical yearbooks are replicated by the crop models AquaCrop and InfoCrop, and by doing so the amount of irrigation water needed to produce the published yields is quantified. In addition, proxy information, for example electrical consumption for agricultural use, is used to verify the likely volumes of water abstracted from tubewells. Statistical analyses of borehole distribution and the characterisation of the spatial heterogeneity of water use practices, particularly farmer decision making, collected during a field trip are also presented. The evolution of agricultural practices, technological advancement and water use for irrigation is reconstructed through the use of multiple regression and principle component analysis

  3. Behavioural modelling of irrigation decision making under water scarcity

    NASA Astrophysics Data System (ADS)

    Foster, T.; Brozovic, N.; Butler, A. P.

    2013-12-01

    Providing effective policy solutions to aquifer depletion caused by abstraction for irrigation is a key challenge for socio-hydrology. However, most crop production functions used in hydrological models do not capture the intraseasonal nature of irrigation planning, or the importance of well yield in land and water use decisions. Here we develop a method for determining stochastic intraseasonal water use that is based on observed farmer behaviour but is also theoretically consistent with dynamically optimal decision making. We use the model to (i) analyse the joint land and water use decision by farmers; (ii) to assess changes in behaviour and production risk in response to water scarcity; and (iii) to understand the limits of applicability of current methods in policy design. We develop a biophysical model of water-limited crop yield building on the AquaCrop model. The model is calibrated and applied to case studies of irrigated corn production in Nebraska and Texas. We run the model iteratively, using long-term climate records, to define two formulations of the crop-water production function: (i) the aggregate relationship between total seasonal irrigation and yield (typical of current approaches); and (ii) the stochastic response of yield and total seasonal irrigation to the choice of an intraseasonal soil moisture target and irrigated area. Irrigated area (the extensive margin decision) and per-area irrigation intensity (the intensive margin decision) are then calculated for different seasonal water restrictions (corresponding to regulatory policies) and well yield constraints on intraseasonal abstraction rates (corresponding to aquifer system limits). Profit- and utility-maximising decisions are determined assuming risk neutrality and varying degrees of risk aversion, respectively. Our results demonstrate that the formulation of the production function has a significant impact on the response to water scarcity. For low well yields, which are the major concern

  4. Ground-water resources of Riverton irrigation project area, Wyoming

    USGS Publications Warehouse

    Morris, Donald Arthur; Hackett, O.M.; Vanlier, K.E.; Moulder, E.A.; Durum, W.H.

    1959-01-01

    The Riverton irrigation project area is in the northwestern part of the Wind River basin in west-central Wyoming. Because the annual precipitation is only about 9 inches, agriculture, which is the principal occupation in the area, is dependent upon irrigation. Irrigation by surface-water diversion was begum is 1906; water is now supplied to 77,716 acres and irrigation has been proposed for an additional 31,344 acres. This study of the geology and ground-water resources of the Riverton irrigation project, of adjacent irrigated land, and of nearby land proposed for irrigation was begun during the summer of 1948 and was completed in 1951. The purpose of the investigation was to evaluate the ground-water resources of the area and to study the factors that should be considered in the solution of drainage and erosional problems within the area. The Riverton irrigation project area is characterized by flat to gently sloping stream terraces, which are flanked by a combination of badlands, pediment slopes, and broad valleys. These features were formed by long-continued erosion in an arid climate of the essentially horizontal, poorly consolidated beds of the Wind River formation. The principal streams of the area flow south-eastward. Wind River and Fivemile Creek are perennial streams and the others are intermittent. Ground-water discharge and irrigation return flow have created a major problem in erosion control along Fivemile Creek. Similar conditions might develop along Muddy and lower Cottonwood Creeks when land in their drainage basins is irrigated. The bedrock exposed in the area ranges in age from Late Cretaceous to early Tertiary (middle Eocene). The Wind River formation of early and middle Eocene age forms the uppermost bedrock formation in the greater part of the area. Unconsolidated deposits of Quaternary age, which consist of terrace gravel, colluvium, eolian sand and silt. and alluvium, mantle the Wind River formation in much of the area. In the irrigated parts

  5. Risk assessment of vegetables irrigated with arsenic-contaminated water.

    PubMed

    Bhatti, S M; Anderson, C W N; Stewart, R B; Robinson, B H

    2013-10-01

    Arsenic (As) contaminated water is used in South Asian countries to irrigate food crops, but the subsequent uptake of As by vegetables and associated human health risk is poorly understood. We used a pot trial to determine the As uptake of four vegetable species (carrot, radish, spinach and tomato) with As irrigation levels ranging from 50 to 1000 μg L(-1) and two irrigation techniques, non-flooded (70% field capacity for all studied vegetables), and flooded (110% field capacity initially followed by aerobic till next irrigation) for carrot and spinach only. Only the 1000 μg As L(-1) treatment showed a significant increase of As concentration in the vegetables over all other treatments (P < 0.05). The distribution of As in vegetable tissues was species dependent; As was mainly found in the roots of tomato and spinach, but accumulated in the leaves and skin of root crops. There was a higher concentration of As in the vegetables grown under flood irrigation relative to non-flood irrigation. The trend of As bioaccumulation was spinach > tomato > radish > carrot. The As concentration in spinach leaves exceeded the Chinese maximum permissible concentration for inorganic As (0.05 μg g(-1) fresh weight) by a factor of 1.6 to 6.4 times. No other vegetables recorded an As concentration that exceeded this threshold. The USEPA parameters hazard quotient and cancer risk were calculated for adults and adolescents. A hazard quotient value greater than 1 and a cancer risk value above the highest target value of 10(-4) confirms potential risk to humans from ingestion of spinach leaves. In our study, spinach presents a direct risk to human health where flood irrigated with water containing an arsenic concentration greater than 50 μg As L(-1). PMID:23934025

  6. Water Management For Drip Irrigated Corn In The Arid Southeastern Anatolia Project Area In Turkey

    NASA Astrophysics Data System (ADS)

    Yazar, A.; Gencel, B.

    Microirrigation has the potential to minimize application losses to evaporation, runoff and deep percolation; improve irrigation control with smaller, frequent applications; supply nutrients to the crop as needed; and improve crop yields. The Southeastern Anatolia Project (GAP), when completed, 1.7 million ha of land will be irrigated. Wa- ter supplies are limited, and traditional irrigation practices result in high losses and low irrigation efficiences. This study was conducted to evaluate surface drip irrigation on crop performance. The effect of irrigation frequency and amount on crop yield, yield components, water use, and water use efficiency of corn (Zea mays L., PIO- 3267) were investigated in the Harran Plain in the arid Southeastern Turkey on a clay textured Harran Soil Series. Irrigation frequencies were once in three-day, and once in six-day; irrigation levels varied from full (I-100), medium (I-67; 2/3rd of full), and low (I-33; 1/3rd of full). The full irrigation treatment received 100% of the cumula- tive evaporation within the irrigation interval. Liquid nitrogen was injected into the irrigation water throughout the growing season. Treatments received the same amount of fertilizers. Highest average corn grain yield (11920 kg/ha) was obtained from the full irrigation treatment (I-100) with six-day irrigation interval. Irrigation intervals did not affect corn yields; however, deficit irrigation affected crop yields by reducing seed mass, and the seed number. Maximum water use efficiency (WUE) was found as 2.27 kg/m3 in the I-33 treatment plots with three-day irrigation interval. On the clay soil at Harran, irrigation frequencies are less critical than proper irrigation management for drip irrigation systems to avoid water deficits that have a greater effect on corn yields. The results revealed that about 40% water saving is possible with drip irrigation as compared to traditional surface irrigation methods in the region.

  7. Characterisation of areas under irrigated agriculture: mapping and water use

    NASA Astrophysics Data System (ADS)

    Peña Arancibia, Jorge; McVicar, Tim R.; Guerschman, Juan P.; Li, Lingtao T.

    2014-05-01

    The evolution of remote sensing and classification methods has enabled effective mapping, monitoring and management of irrigated agriculture. A random forest classification was implemented using learning samples inferred from Landsat TM/ETM data and monthly time-series of remotely-sensed observations from the MODerate resolution Imaging Spectroradiometer (MODIS). The covariates included in the method characterised: (i) the vegetation phenology via the recurrent and persistent fractions of photosynthetically active radiation (fPARrecandfPARper, respectively); (ii) vegetation water use via estimates of actual evapotranspiration (AET), rainfall (P) and the difference between AET and P . Maps of irrigated areas under different climates and cropping conditions were produced for the whole Murray-Darling Basin (Australia) for the years 2004 to 2010 with 0.96 observed agreement in terms of the Kappa Index (were a value of 1 indicates perfect agreement). An independent comparison of yearly irrigated area estimates and corresponding water use showed a linear relationship with good agreement (R2 >0.7) against available yearly metered water withdrawals and estimates of agricultural yields. A sequential covariate optimisation suggested that the most important predictors included the emergence-senescence period (as determined by the fPARrec and corresponding rates of change) and the AET surplus over P during this period. The latter can be important when determining more opportunistic irrigation practices due to unreliable water supply in areas with otherwise high annual rainfall. The procedure can be implemented to map irrigated areas at the global scale: the MODIS time-series used in the classification methodology are available globally since February 2000 and so are the Landsat archives which can be used to infer learning samples and irrigation practices elsewhere.

  8. Climate change and the water cycle in newly irrigated areas.

    PubMed

    Abrahão, Raphael; García-Garizábal, Iker; Merchán, Daniel; Causapé, Jesús

    2015-02-01

    Climate change is affecting agriculture doubly: evapotranspiration is increasing due to increments in temperature while the availability of water resources is decreasing. Furthermore, irrigated areas are expanding worldwide. In this study, the dynamics of climate change impacts on the water cycle of a newly irrigated watershed are studied through the calculation of soil water balances. The study area was a 752-ha watershed located on the left side of the Ebro river valley, in Northeast Spain. The soil water balance procedures were carried out throughout 1827 consecutive days (5 years) of hydrological and agronomical monitoring in the study area. Daily data from two agroclimatic stations were used as well. Evaluation of the impact of climate change on the water cycle considered the creation of two future climate scenarios for comparison: 2070 decade with climate change and 2070 decade without climate change. The main indicators studied were precipitation, irrigation, reference evapotranspiration, actual evapotranspiration, drainage from the watershed, and irrigation losses. The aridity index was also applied. The results represent a baseline scenario in which adaptation measures may be included and tested to reduce the impacts of climate change in the studied area and other similar areas. PMID:25626569

  9. Characterizing water flows in irrigated valleys of northern New Mexico

    NASA Astrophysics Data System (ADS)

    Ochoa, C. G.; Fernald, A.; Guldan, S.; Tidwell, V. C.

    2009-12-01

    Ditch seepage and deep percolation from irrigation in agricultural valleys of semi-arid regions can have multiple hydrological benefits including aquifer recharge, temporary storage, and delayed return flow. This study aims to advance scientific understanding of surface water and groundwater interactions in semi-arid region valleys of the western USA. The study is being conducted in three different irrigated valleys of the Rio Grande basin in northern New Mexico. The first site is a floodplain valley along the main stem of the Rio Grande; the second site is an upper valley along the Rio Hondo, a tributary to the Rio Grande; and the third site is a floodplain valley along the Rio Chama, which also is a tributary to the Rio Grande. Beginning in 2002, we instrumented the first study site to measure climate variables, surface water flows, and groundwater fluctuations due to deep percolation from irrigation and ditch seepage. Currently, we are installing field equipment at the second study site, and we will start instrumentation at the third study site in the spring of 2010. A multi-modeling approach is being used to extrapolate field-based results to larger spatial scales. One and two dimensional models like the Root Zone Water Quality Model and Hydrus, respectively, are being used to simulate physical processes in the vadose zone at the field scale, and the model GSFlow will be used to integrate surface water and groundwater components at the valley scale. Results from an ongoing study aimed to quantify water budget components at the first study site showed that up to 92% of the water diverted for irrigation in this floodplain valley returns back to the river, either as surface return flow (59%) or as shallow groundwater return flow that originated as canal seepage (12%) and deep percolation from irrigation (21%). Also, simulations with a System Dynamics Model showed that the coupled surface water irrigation system and shallow aquifer act together to store water

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  11. Use of saline and recycled water as an alternative irrigation water supply: Chemical and agronomic considerations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Predictions of increased occurrences of drought in the SW U.S. coupled with increasing urban demands for fresh water have resulted in projections of decreased irrigated acreage. However, agriculture can utilize saline, drainage and treated municipal and industrial waste waters for irrigation of many...

  12. Irrigation management using an expert system, soil water potentials, and vegetative indices for spatial applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variable rate irrigation (VRI) systems are irrigation systems that are capable of applying different water depths both in the direction of travel and along the length of the irrigation system. However, when compared to traditional irrigation systems, VRI systems require a higher level of management...

  13. Impact of reclaimed water irrigation on soil health in urban green areas.

    PubMed

    Chen, Weiping; Lu, Sidan; Pan, Neng; Wang, Yanchun; Wu, Laosheng

    2015-01-01

    Rapid increase of reclaimed water irrigation in urban green areas requires investigating its impact on soil health conditions. In this research, field study was conducted in 7 parks in Beijing with different histories of reclaimed water irrigation. Twenty soil attributes were analyzed to evaluate the effects of reclaimed water irrigation on the soil health conditions. Results showed that soil nutrient conditions were ameliorated by reclaimed water irrigation, as indicated by the increase of soil organic matter content (SOM), total nitrogen (TN), and available phosphorus (AP). No soil salinization but a slight soil alkalization was observed under reclaimed water irrigation. Accumulation of heavy metals in soil was insignificant. It was also observed that reclaimed water irrigation could significantly improve the soil microorganism activities. Overall, the soil health conditions were improved with reclaimed water irrigation, and the improvement increased when the reclaimed water irrigation period became longer. PMID:25150469

  14. PATHOGENIC PHYTOPHTHORA SPECIES IN SAN JOAQUIN VALLEY IRRIGATION WATER SOURCES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface sources of irrigation water including the Kings River and three canals were assayed for Phytophthora spp. at six locations in the San Joaquin Valley within 30 km of Hanford, CA. Four nylon-mesh bags, each containing three firm, green pear fruits (separated by Styrofoam blocks) as bait for Ph...

  15. Interpretation of Thermal Infrared Imagery for Irrigation Water Resource Management.

    ERIC Educational Resources Information Center

    Nellis, M. Duane

    1985-01-01

    Water resources play a major role in the character of agricultural development in the arid western United States. This case study shows how thermal infrared imagery, which is sensitive to radiant or heat energy, can be used to interpret crop moisture content and associated stress in irrigated areas. (RM)

  16. Stewardship of water and fertilizer in irrigated cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture is a vital part of the southeast Missouri economy and it is essential that we maintain our precious soil and water resources. While we have shallow, high quality groundwater for irrigation, it is important to realize that our aquifer, the Mississippi River Valley Alluvial Aquifer, also p...

  17. Global net irrigation water requirements from various water supply sources during past and future periods

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Cho, J.; Hanasaki, N.; Kanae, S.

    2014-12-01

    Water supply sources for irrigation (e.g. rivers and reservoirs) are critically important for agricultural productivity. The current rapid increase in irrigation water use is considered unsustainable and threatens food production. In this study, we estimated the time-varying dependence of irrigation water requirements from water supply sources, with a particular focus on variations in irrigation area during past (1960-2001) and future (2002-2050) periods using the global water resources model, H08. The H08 model can simulate water requirements on a daily basis at a resolution of 1.0° × 1.0° latitude and longitude. The sources of irrigation water requirements in the past simulations were specified using four categories: rivers (RIV), large reservoirs (LR), medium-size reservoirs (MSR), and non-local non-renewable blue water (NNBW). The simulated results from 1960 to 2001 showed that RIV, MSR and NNBW increased significantly from the 1960s to the early 1990s globally, but LR increased at a relatively low rate. After the early 1990s, the increase in RIV declined as it approached a critical limit, due to the continued expansion of irrigation area. MSR and NNBW increased significantly, during the same time period, following the expansion of the irrigation area and the increased storage capacity of the medium-size reservoirs. We also estimated future irrigation water requirements from the above four water supply sources and an additional water supply source (ADD) in three future simulation designs; irrigation area change, climate change, and changes in both irrigation area and climate. ADD was defined as a future increase in NNBW. After the 2020s, MSR was predicted to approach the critical limit, and ADD would account for 11-23% of the total requirements in the 2040s.

  18. Comparison of Irrigation Water Use Estimates Calculated from Remotely Sensed Irrigated Acres and State Reported Irrigated Acres in the Lake Altus Drainage Basin, Oklahoma and Texas, 2000 Growing Season

    USGS Publications Warehouse

    Masoner, J.R.; Mladinich, C.S.; Konduris, A.M.; Smith, S. Jerrod

    2003-01-01

    Increased demand for water in the Lake Altus drainage basin requires more accurate estimates of water use for irrigation. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is investigating new techniques to improve water-use estimates for irrigation purposes in the Lake Altus drainage basin. Empirical estimates of reference evapotranspiration, crop evapotranspiration, and crop irrigation water requirements for nine major crops were calculated from September 1999 to October 2000 using a solar radiation-based evapotranspiration model. Estimates of irrigation water use were calculated using remotely sensed irrigated crop acres derived from Landsat 7 Enhanced Thematic Mapper Plus imagery and were compared with irrigation water-use estimates calculated from irrigated crop acres reported by the Oklahoma Water Resources Board and the Texas Water Development Board for the 2000 growing season. The techniques presented will help manage water resources in the Lake Altus drainage basin and may be transferable to other areas with similar water management needs. Irrigation water use calculated from the remotely sensed irrigated acres was estimated at 154,920 acre-feet; whereas, irrigation water use calculated from state reported irrigated crop acres was 196,026 acre-feet, a 23 percent difference. The greatest difference in irrigation water use was in Carson County, Texas. Irrigation water use for Carson County, Texas, calculated from the remotely sensed irrigated acres was 58,555 acrefeet; whereas, irrigation water use calculated from state reported irrigated acres was 138,180 acre-feet, an 81 percent difference. The second greatest difference in irrigation water use occurred in Beckham County, Oklahoma. Differences between the two irrigation water use estimates are due to the differences of irrigated crop acres derived from the mapping process and those reported by the Oklahoma Water Resources Board and Texas Water Development Board.

  19. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    NASA Astrophysics Data System (ADS)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  20. [Theme: Horticulture Programs.

    ERIC Educational Resources Information Center

    Henderson, Jan; And Others

    1982-01-01

    A series of articles discusses requirements for optimum growth of horticulture education programs. Includes beginning a program, simulating working conditions, the need for mechanical skills, starting a business, and other areas to be considered for a successful horticultural program. (JOW)

  1. Horticulture and the FFA

    ERIC Educational Resources Information Center

    Nelson, Clifford L.

    1975-01-01

    The article offers teachers of vocational horticulture a number of specific suggestions for organizing FFA horticulture chapters that will appeal to urban and suburban students and that will improve the quality of their learning. (AJ)

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

    NASA Technical Reports Server (NTRS)

    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.

  3. Effects of irrigation on crops and soils with Raft River geothermal water

    SciTech Connect

    Stanley, N.E.; Schmitt, R.C.

    1980-01-01

    The Raft River Irrigation Experiment investigated the suitability of using energy-expended geothermal water for irrigation of selected field-grown crops. Crop and soil behavior on plots sprinkled or surface irrigated with geothermal water was compared to crop and soil behavior on plots receiving water from shallow irrigation wells and the Raft River. In addition, selected crops were produced, using both geothermal irrigation water and special management techniques. Crops irrigated with geothermal water exhibited growth rates, yields, and nutritional values similar to comparison crops. Cereal grains and surface-irrigated forage crops did not exhibit elevated fluoride levels or accumulations of heavy metals. However, forage crops sprinkled with geothermal water did accumulate fluorides, and leaching experiments indicate that new soils receiving geothermal water may experience increased salinity, exchangeable sodium, and decreased permeability. Soil productivity may be maintained by leaching irrigations.

  4. Estimated Domestic, Irrigation, and Industrial Water Use in Washington, 2000

    USGS Publications Warehouse

    Lane, R.C.

    2004-01-01

    Since 1950, the U.S. Geological Survey has published a series of Circulars and other reports on the estimated use of water in the United States at 5-year intervals. This report presents State, regional, and county estimates of the amount of water used for domestic, irrigation, and industrial purposes in the State of Washington during the year 2000. Domestic water use was estimated to be 674 million gallons per day and the per-capita rate, 114 gallons per day. Crop-irrigation water use was estimated to be 3,005 million gallons per day and the application rate, 2.2 acre-feet per acre per year, or feet per year. Golf-course irrigation water use was estimated to be 23.6 million gallons per day and the application rate, 1.4 feet per year. Industrial water use was estimated to be 681 million gallons per day. Historically, these core categories account for about 92 percent of the estimated offstream water used in Washington.

  5. Food security, irrigation, climate change, and water scarcity in India

    NASA Astrophysics Data System (ADS)

    Hertel, T. W.; Taheripour, F.; Gopalakrishnan, B. N.; Sahin, S.; Escurra, J.

    2015-12-01

    This paper uses an advanced CGE model (Taheripour et al., 2013) coupled with hydrological projections of future water scarcity and biophysical data on likely crop yields under climate change to examine how water scarcity, climate change, and trade jointly alter land use changes across the Indian subcontinent. Climate shocks to rainfed and irrigated yields in 2030 are based on the p-DSSAT crop model, RCP 2.6, as reported under the AgMIP project (Rosenzweig et al., 2013), accessed through GEOSHARE (Villoria et al, 2014). Results show that, when water scarcity is ignored, irrigated areas grow in the wake of climate change as the returns to irrigation rise faster than for rainfed uses of land within a given agro-ecological zone. When non-agricultural competition for future water use, as well as anticipated supply side limitations are brought into play (Rosegrant et al., 2013), the opportunity cost of water rises across all river basins, with the increase ranging from 12% (Luni) to 44% (Brahmaputra). As a consequence, irrigated crop production is curtailed in most regions (Figure 1), with the largest reductions coming in the most water intensive crops, namely rice and wheat. By reducing irrigated area, which tends to have much higher yields, the combined effects of water scarcity and climate impacts require an increase in total cropped area, which rises by about 240,000 ha. The majority of this area expansion occurs in the Ganges, Indus, and Brahmari river basins. Overall crop output falls by about 2 billion, relative to the 2030 baseline, with imports rising by about 570 million. The combined effects of climate change and water scarcity for irrigation also have macro-economic consequences, resulting in a 0.28% reduction in GDP and an increase in the consumer price index by about 0.4% in 2030, compared the baseline. The national welfare impact on India amounts to roughly 3 billion (at 2007 prices) in 2030. Assuming a 3% social discount rate, the net present value of the

  6. Assessment of reclaimed water irrigation on growth, yield, and water-use efficiency of forage crops

    NASA Astrophysics Data System (ADS)

    Alkhamisi, S. A.; Abdelrahman, H. A.; Ahmed, M.; Goosen, M. F. A.

    2011-09-01

    Field experiments were conducted to determine the effect of water quality (reclaimed and fresh water), water quantity, and their interactions on the growth, yield, and water use efficiency of forage maize during two winter seasons in the Arabian Gulf. The plants irrigated with the reclaimed water had higher plant height than those irrigated with the fresh water. The leaf length and leaf area (cm2) did not show any significant differences among the interaction. Reclaimed water had shorter time for 50% male and female flowering of forage maize plants, indicating earlier maturity. Plants irrigated with reclaimed water had higher chlorophyll content for all levels of water applications. A significant difference in green forage yield was found among the interactions. Reclaimed water gave the highest green forage yield of 72.12 and 59.40 t/ha at 1.4ETo and 1.0ETo, respectively. Plants irrigated with the reclaimed water used water more efficiently [3.65 kg/m3 of DM (dry matter)] than those irrigated with the fresh water [2.91 kg/m3 of DM (dry matter)] for all water quantities. The enhanced growth in wastewater-irrigated crops, compared with fresh water-irrigated crops, was attributed primarily to higher nutrient content (e.g., nitrogen) and lower salinity of the reclaimed water. The study concluded that treated wastewater irrigation increased yields of forage crops and their water use efficiency. Cost-benefit analysis, studies on the use these forage crops as animal feed, and more in depth evaluation of possible crop and soil contamination were recommended.

  7. PERCHLORATE CROP INTERACTIONS VIA CONTAMINATED IRRIGATION WATER

    EPA Science Inventory

    Perchlorate has contaminated water and sods at several locations in the United States. Perchlorate is water soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground- and surface water conditions. Perchlorate is of concern because of un...

  8. Integrated water resource management under water supply and irrigation development uncertainty

    NASA Astrophysics Data System (ADS)

    Hassanzadeh, E.; Elshorbagy, A. A.; Nazemi, A.; Wheater, H. S.; Gober, P.

    2014-12-01

    The Saskatchewan River Basin (SaskRB) in Saskatchewan, Canada, supports various water demands including municipal, industrial, irrigated agriculture, hydropower and environmental sectors. Proposals for future development include significantly increased irrigation. However, proposing an appropriate level of irrigation development requires incorporation of water supply uncertainties in the water resources management analysis, including effects of climate variability and change. To evaluate potential climate change effects, a feasible range of shifts in annual volume and peak timing of headwater flows are considered to stochastically generate flows at the Alberta/Saskatchewan border. This envelope of flows, 30,800 realizations, is further combined with various irrigation expansion areas to form various future scenarios. Using an integrated water resources model developed for Saskatchewan, the impact of irrigation development on the system is assessed under the changing water supply conditions. The results of this study show that level of irrigation development as well as variation in volume and peak timing of flows can all contribute to change the water availability, vulnerability and economic productivity of the water resources system in Saskatchewan. In particular, the combined effect of large irrigation expansion, reduction in the volume of flows and earlier timing of the annual peak can exacerbate water resources system vulnerability, produce unstable net revenues, and decrease flood frequency in the Saskatchewan River Delta.

  9. Incentives and technologies for improving irrigation water use efficiency

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    The European Water Framework Directive requires Member States to set water prices that provide adequate incentives for users to use water resources efficiently. These new water pricing policies need to consider cost recovery of water services, including financial, environmental and resource cost. Prices were supposed to have been set by 2010. So far the record has been mixed. The European Commission has sent reasoned opinions to a number of countries (Austria, Belgium, Denmark, Estonia, Finland, Germany, Hungary, Netherlands, Sweden) requesting them to adjust their national legislation to include all water services. Unbalanced water pricing may negatively affect the agricultural sector, especially in the southern EU countries, which are more dependent on irrigation water for production. The European Commission is funding several projects that aim to reduce the burden of increasing water prices on farmers by developing innovative technologies and decision support systems that will save water and increase productivity. The FP7 ENORASIS project (grant 282949) has developed a new integrated irrigation management decision support platform, which include high-resolution, ensemble weather forecasting, a GIS widget for the location of fields and sensors and a comprehensive decision support and database management software package to optimize irrigation water management. The field component includes wireless, solar-powered soil moisture sensors, small weather stations, and remotely controlled irrigation valves. A mobile App and a web-package are providing user-friendly interfaces for farmers, water companies and environmental consultants. In Cyprus, agricultural water prices have been set to achieve a cost recovery rate of 54% (2010). The pricing policy takes in consideration the social importance and financial viability of the agricultural sector, an important flexibility provided by the Water Framework Directive. The new price was set at 0.24 euro per m3 for water supply

  10. Yield and Irrigation Water Use Efficiency Response of Chufa (Cyperus esculentus L. var. sativus Boeck.) to Drip Irrigation Management

    NASA Astrophysics Data System (ADS)

    Pascual-Seva, Nuria; San Bautista, Alberto; López-Galarza, Salvador; Maroto, José Vicente; Pascual, Bernardo

    2016-04-01

    Chufa, also known as tigernut, is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. Its cultivation uses large amounts of water, in the order of 10,000 m3 ha‑1 year‑1, so different studies have been undertaken in order to maximize the irrigation water use efficiency (IWUE). One of these studies faced the application of drip irrigation in the chufa cultivation, comparing three different irrigation strategies. These strategies differed on the volumetric soil water content (VSWC) when each irrigation event started. Starting each irrigation when the VSWC dropped to 90% of field capacity (FC) leaded to the highest yield, while the highest IWUE was obtained when irrigation started at 80% FC. It can be stated that starting each irrigation event when the VSWC is between 80 and 90% FC leads to the best results in terms of yield and IWUE. However, these results may still be improved by defining the best strategy in the irrigation stop, which is the aim of the herein presented research. This investigation comprises the productive response of the chufa crop with drip irrigation, determining yield and IWUE. The VSWC was monitored using multi-depth capacitance probes, with sensors at 0.10, 0.20 and 0.30 m below the top of the ridge. Each irrigation event started when the volumetric soil water content at 0.10 m dropped to 85% FC. Three irrigation strategies were considered, T1: each event being stopped when the average of the VSWC values at 0.10, 0.20 and 0.30 m depth reached the corresponding FC value; T2: each event being stopped when the VSWC values at 0.20 m reached the corresponding FC value; T3 each irrigation event lasted 30 min (corresponding to 7.33 mm). The largest yield (P ≤0.05) was obtained in T2 (2.31 kg m‑2), with no statistical differences (P ≤0.05) between T1 (1.94 kg m‑2) and T3 (1.92 kg m‑2). The highest yield in T2 was obtained with the largest volume of irrigation water applied (722 mm), resulting in the

  11. Subsurface drip irrigation emitter spacing effects on soil water redistribution, corn yield, and water productivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emitter spacings of 0.3 to 0.6 m are commonly used for subsurface drip irrigation (SDI) of corn on the deep, silt loam soils of the United States Great Plains. Subsurface drip irrigation emitter spacings of 0.3, 0.6, 0.9 and 1.2 m were examined for the resulting differences in soil water redistribut...

  12. Balancing water scarcity and quality for sustainable irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Assouline, Shmuel; Russo, David; Silber, Avner; Or, Dani

    2015-05-01

    The challenge of meeting the projected doubling of global demand for food by 2050 is monumental. It is further exacerbated by the limited prospects for land expansion and rapidly dwindling water resources. A promising strategy for increasing crop yields per unit land requires the expansion of irrigated agriculture and the harnessing of water sources previously considered "marginal" (saline, treated effluent, and desalinated water). Such an expansion, however, must carefully consider potential long-term risks on soil hydroecological functioning. The study provides critical analyses of use of marginal water and management approaches to map out potential risks. Long-term application of treated effluent (TE) for irrigation has shown adverse impacts on soil transport properties, and introduces certain health risks due to the persistent exposure of soil biota to anthropogenic compounds (e.g., promoting antibiotic resistance). The availability of desalinated water (DS) for irrigation expands management options and improves yields while reducing irrigation amounts and salt loading into the soil. Quantitative models are used to delineate trends associated with long-term use of TE and DS considering agricultural, hydrological, and environmental aspects. The primary challenges to the sustainability of agroecosystems lies with the hazards of saline and sodic conditions, and the unintended consequences on soil hydroecological functioning. Multidisciplinary approaches that combine new scientific knowhow with legislative, economic, and societal tools are required to ensure safe and sustainable use of water resources of different qualities. The new scientific knowhow should provide quantitative models for integrating key biophysical processes with ecological interactions at appropriate spatial and temporal scales.

  13. Rational use of water in trickle irrigation design.

    NASA Astrophysics Data System (ADS)

    Saad, J. C. C.; da Silva Junior, H. M.

    2012-04-01

    In trickle irrigation systems, the design is based on the pre-established emission uniformity (EU) which is the combined result of the equipment characteristics and its hydraulic configuration. However, this desired value of the EU may not be confirmed by the final project (in field conditions) and neither by the yield uniformity. However, the most important is to assure yield uniformity with rational use of water. The hypotheses of this research were: a) the EU of a trickle irrigation system at field conditions is equal to the emission uniformity pre-established in the design; b) EU has always the lowest value when compared with other indicators of uniformity; c) the discharge variation coefficient is not equal to production variation coefficient in the operational unit; d) the productivity variation coefficient is more dependent on water depth applied than the EU. This study aimed to evaluate the relationships among EU used in the irrigation system design, water depth applied and the final yield uniformity. The uniformity indicators evaluated were: EU, distribution uniformity (UD) and the index proposed by Barragan & Wu (2005). They were compared estimating the performance of a trickle irrigation system applied in a citrus orchard with dimensions of 400m x 600m. The design of the irrigation system was optimized by a Linear Programming model. The tree rows were leveled in the larger direction and the spacing adopted in the orchard was 7m x 4m. The manifold line was always operating on a slope condition. The sensitivity analysis involved different slopes, 0, 3, 6, 9 and 12%, and different values of emission uniformity, 60, 70, 75, 80, 85, 90 and 94%. The citrus yield uniformity was evaluated by the variation coefficient. The emission uniformity (EU) after design differed from the EU pre-established, more sharply in the initial values lower than 90%. Comparing the uniformity indexes, the EU always generated lower values when compared with the UD and with the index

  14. Soil quality assessment of urban green space under long-term reclaimed water irrigation.

    PubMed

    Lyu, Sidan; Chen, Weiping

    2016-03-01

    Reclaimed water is widely used for landscape irrigation with the benefits of saving fresh water and ameliorating soil quality. Field samples were collected from seven parks in Beijing irrigated reclaimed water with different irrigation history in 2011 and 2014 to evaluate the long-term impacts of reclaimed water irrigation on soil quality. Soil quality index method was used to assess the comprehensive effects of reclaimed water irrigation on soil. Results showed that the effects of reclaimed water irrigation on the soil nutrient conditions were limited. Compared with tap water irrigation, soil salinity was significantly higher in 2011, while the difference was insignificant in 2014; soil heavy metals were slightly higher by 0.5-10.6 % in 2011 and 2014, while the differences were insignificant. Under reclaimed water irrigation, soil biological activities were significantly improved in both years. Total nitrogen in reclaimed water had a largest effect on soil quality irrigated reclaimed water. Soil quality irrigated with reclaimed water increased by 2.6 and 6.8 % respectively in 2011 and 2014, while the increases were insignificant. Soil quality of almost half samples was more than or closed to soil quality of natural forest in Beijing. Soil quality was ameliorated at some extent with long-term reclaimed water irrigation. PMID:26527339

  15. Infiltration into cropped soils: Effect of rain and sodium adsorption ration - impacted irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The SAR salinity criteria for irrigation have been developed for conditions where the irrigation water is the only source of water supply. It is not clear that these criteria are applicable to conditions where there are rain and irrigation events during the growing season. The low electrical conduct...

  16. Water distribution in traditionally irrigated valleys under different scenarios of water availability in Northern New Mexico

    NASA Astrophysics Data System (ADS)

    Cruz, J. J.; Fernald, A.; Gutierrez, K. Y.; Ochoa, C. G.; Guldan, S. J.

    2014-12-01

    Population growth and water scarcity are factors that increase pressures on water resources of the semiarid southwestern United States. In these areas, groundwater recharge and delayed return flow to rivers are hydrological benefits of traditional irrigation systems. A broad spatial-temporal analysis of the dynamics of surface water and groundwater interactions is necessary to improve water planning and management. Our study at three northern New Mexico agricultural valleys with low to high water availability was carried out to characterize surface water and groundwater interactions and to quantify different water budget components. The study sites were instrumented to collect weather data, water flows from rivers and acequias, shallow groundwater level fluctuations, soil physical properties and irrigation and crop management on irrigated lands. From one crop field of our study sites, results showed up to 38 cm of water level response after the beginning of an irrigation event. Other results in our study sites, showed water level response up to 80 cm after canal flow started and ditch seepage of 12% of the total valley surface water flow. Preliminary field scale results from our three study sites showed that deep percolation from irrigation is the major component of the total water budget with 43, 46 and 52% from low, medium and high water availability sites respectively. This farm scale study revealed that, water availability drives the amount of applied water and the irrigation schedule on the farms that in turn drive deep percolation and shallow aquifer recharge. It appears that traditional irrigation is an important source of groundwater recharge in our study valleys. From the ongoing study, we expect to get detailed information about the water distribution over larger spatial scales using field measurements and geographic information systems-based land use classification.

  17. Unexpected Increases in Fecundity of Ceriodaphnia dubia Exposed to Reused Rice Irrigation Water.

    PubMed

    Grippo, Richard S; McNeely, Van M; Farris, Jerry L

    2016-06-01

    Steady increases in agricultural irrigation raise concerns about environmental impacts. Rice producing regions face declining irrigation groundwater and have started reusing irrigation water as a substitute. The goal of this project was to determine if reused irrigation water is potentially toxic compared to conventional well irrigation water. Reused and well water samples, collected from three Arkansas rice farms at field inlets and outlets on three dates corresponding to fertilizer/chemical applications or crop management, were used in acute 48-h (Pimephales promelas) and chronic (Ceriodaphnia dubia) toxicity evaluations. Acute toxicity tests indicated no effects on P. promelas. Fecundity of C. dubia was significantly increased in the reused water inlet and in both the reused and well water rice field outlets compared to well water inlets and laboratory reference water. This study suggests that, compared to well water, reused rice irrigation water has reduced potential for significant negative environmental impact on biota in receiving waters. PMID:27189359

  18. Overview of advances in water management in agricultural production:Sensor based irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technological advances in irrigated agriculture are crucial to meeting the challenge of increasing demand for agricultural products given limited quality and quantity of water resources for irrigation, impacts of climate variability, and the need to reduce environmental impacts. Multidisciplinary ap...

  19. Surface Water and Ground Water Interactions in an Irrigated Valley in Northern New Mexico

    NASA Astrophysics Data System (ADS)

    Ochoa, C.; Fernald, A.; Guldan, S.; Tidwell, V.; King, P.; Cevik, Y.; Cusack, C.

    2008-12-01

    Interactions between surface water and ground water can provide many benefits like terrestrial and aquatic species habitat, aquifer recharge, and shallow ground water return flow. In northern New Mexico, the use of traditional irrigation systems has effectively expanded riparian functions to encompass full irrigated valley width. The objective of this study was to characterize the surface water and ground water interactions occurring in an irrigated valley along the Rio Grande in northern New Mexico. We used a combination of field measurements and modeling for determining different components of the water budget. Our results show that on average ditch flow is 0.9 cms, ditch seepage is 10%, irrigated field deep percolation is 30%, and ground water level rise is 0.4 m over the entire valley after the irrigation season started. We calculated that on average, 50% of the water diverted into the main irrigation ditch returns back to the river as surface return flow and about 10% of the total ditch inflow returns as groundwater flow. Results from this study show that a significant amount of water being diverted into the valley returns back to the river after completing its task of supporting important production and ecological functions in this expanded riverine valley.

  20. Microbiological irrigation water quality of the Marchfeld canal system.

    PubMed

    Stauffer, F; Makristathis, A; Hassl, A; Nowotny, S; Neudorfer, W

    2001-07-01

    The Marchfeld basin with a size of approximately 1000 km2 represents the Austrian "granary". To prevent shortage of water as a result of increased ground water removal for irrigation, industrial purposes and drinking water supply, a canal being 18 km in length was constructed from the Danube to the center of the Marchfeld. From there, water is further distributed via two creeks (Russbach and Stempfelbach). This study was intended to evaluate whether the surface water of the Marchfeld canal system can be classified into hygienic-microbiological categories as proposed by DIN (Deutsche Industrienorm) standards for irrigation water. For this purpose, water sampled monthly from three different sampling sites from 1996 to 1999 was examined for E. coli and enterococci. In addition, water samples were examined for salmonella twice a year from 1996 to 1998 and for cryptosporidia six times during the year 1999. Though the water showed varying degrees of fecal load, the results of the examinations revealed that only one of the three sampling sites showed constant quality levels according to the DIN classification system over prolonged periods of time. However, exceeding of the limit values was occasionally observed indicating the need for regular bacteriological examinations. The high variation of the results from the other sampling sites hardly permits a definite classification in one of the quality classes. PMID:11556148

  1. Irrigation water demand: A meta-analysis of price elasticities

    NASA Astrophysics Data System (ADS)

    Scheierling, Susanne M.; Loomis, John B.; Young, Robert A.

    2006-01-01

    Metaregression models are estimated to investigate sources of variation in empirical estimates of the price elasticity of irrigation water demand. Elasticity estimates are drawn from 24 studies reported in the United States since 1963, including mathematical programming, field experiments, and econometric studies. The mean price elasticity is 0.48. Long-run elasticities, those that are most useful for policy purposes, are likely larger than the mean estimate. Empirical results suggest that estimates may be more elastic if they are derived from mathematical programming or econometric studies and calculated at a higher irrigation water price. Less elastic estimates are found to be derived from models based on field experiments and in the presence of high-valued crops.

  2. Irrigation in water restricted regions: Managing water use efficiency with limited available water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Political and social pressures to increase water-use efficiency in agriculture from plant to regional scales are reaching critical levels. A region where these pressures have been extremely acute is most semi-arid parts of Texas where reliable crop production is possible only through irrigation. Re...

  3. Quantifying crop water stress factors from soil water measurements in a limited irrigation experiment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantifying crop water stress factors from soil water measurements in a limited irrigation experiment. A correct simulation of crop responses to water stress is essential for a system model. In this study, we investigated three methods of quantifying water deficit stresses based on soil water meas...

  4. Field kites: Crop-water production functions and the timing of water application for supplementary irrigation

    NASA Astrophysics Data System (ADS)

    Smilovic, M.; Gleeson, T.; Adamowski, J. F.

    2015-12-01

    Agricultural production is directly related to water management and water supply. The temporal distribution of water use throughout the growing season can significantly influence crop yield, and the facility to manage both the timing and amount of irrigation water may result in higher yields. The crop-water production function quantitatively evaluates the relationship between seasonal water use and crop yield. Previous efforts have attempted to describe and formalize the crop-water production function as a single-variable function of seasonal water use. However, these representations do not account for the effects of temporal distribution of water use and trivialize the associated variability in yields by assuming an optimized or arbitrary temporal distribution of soil moisture. This over-simplification renders the function inappropriate for recommendations related to irrigation scheduling, water management, economically optimal irrigation, water and agricultural productivity, and assessing the role of full and supplementary irrigation. We propose field kites, a novel representation of the crop-water production function that explicitly acknowledges crop yield variability as a function of both seasonal water use and associated temporal distributions of water use. Field kites are a tool that explicitly considers the farmers' capacity to manage their water resources, to more appropriately evaluate the optimal depth of irrigation water under water-limiting conditions. The field kite for winter wheat is presented both generally and cultivar- and climate-specific for Western Canada. The field kites are constructed using AquaCrop and previously validated cultivar-specific variables. Field kites provide the tools for water authorities and policy makers to evaluate agricultural production as it relates to farm water management, and to determine appropriate policies related to developing and supporting the necessary irrigation infrastructure to increase water productivity.

  5. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mode...

  6. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  7. Water-saving techniques in Chinese agriculture: water-saving irrigation and straw mulching for winter wheat

    NASA Astrophysics Data System (ADS)

    Zhao, Guoqiang; Zhu, Zixi; Zheng, Youfei; Fang, Wensong

    2004-01-01

    Based on the relationship between water balance and crop-water, water-saving irrigation model was integrated with monitoring and prediction of soil moisture, forming a system of decision-making of irrigation. It is demonstrated that straw mulching for winter wheat is an effective way to reduce soil evaporation at early stages and increase yield and improve water utilization efficiency. Combination of water-saving irrigation and straw mulching plays an important role in China water-saving agriculture.

  8. Water balance and irrigation water pumping of Lake Merdada for potato farming in Dieng Highland, Indonesia.

    PubMed

    Fadlillah, Lintang N; Widyastuti, M

    2016-08-01

    Lakes provide water resources for domestic use, livestock, irrigational use, etc. Water availability of lakes can be estimated using lake water balance. Lake water balance is calculated from the water input and output of a lake. Dieng Highland has several volcanic lakes in its surroundings. Lake Merdada in Dieng Highland has been experiencing extensive water pumping for several years more than other lakes in the surrounding area. It provides irrigation water for potato farming in Dieng Highland. The hydrological model of this lake has not been studied. The modeled water balance in this research uses primary data, i.e., bathymetric data, soil texture, and outflow discharge, as well as secondary data, i.e., rainfall, temperature, Landsat 7 ETM+ band 8 image, and land use. Water balance input components consist of precipitation on the surface area, surface (direct) runoff from the catchment area, and groundwater inflow and outflow (G net), while the output components consist of evaporation, river outflow, and irrigation. It shows that groundwater is the dominant input and output of the lake. On the other hand, the actual irrigation water pumping plays the leading role as human-induced alteration of outflow discharge. The maximum irrigation pumping modeling shows that it will decrease lake storage up to 37.14 % per month and may affect the ecosystem inside the lake. PMID:27384226

  9. SEBAL Model Using to Estimate Irrigation Water Efficiency & Water Requirement of Alfalfa Crop

    NASA Astrophysics Data System (ADS)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2013-04-01

    The sustainability of irrigation is a complex and comprehensive undertaking, requiring an attention to much more than hydraulics, chemistry, and agronomy. A special combination of human, environmental, and economic factors exists in each irrigated region and must be recognized and evaluated. A way to evaluate the efficiency of irrigation water use for crop production is to consider the so-called crop-water production functions, which express the relation between the yield of a crop and the quantity of water applied to it or consumed by it. The term has been used in a somewhat ambiguous way. Some authors have defined the Crop-Water Production Functions between yield and the total amount of water applied, whereas others have defined it as a relation between yield and seasonal evapotranspiration (ET). In case of high efficiency of irrigation water use the volume of water applied is less than the potential evapotranspiration (PET), then - assuming no significant change of soil moisture storage from beginning of the growing season to its end-the volume of water may be roughly equal to ET. In other case of low efficiency of irrigation water use the volume of water applied exceeds PET, then the excess of volume of water applied over PET must go to either augmenting soil moisture storage (end-of-season moisture being greater than start-of-season soil moisture) or to runoff or/and deep percolation beyond the root zone. In presented contribution some results of a case study of estimation of biomass and leaf area index (LAI) for irrigated alfalfa by SEBAL algorithm will be discussed. The field study was conducted with aim to compare ground biomass of alfalfa at some irrigated fields (provided by agricultural farm) at Saratov and Volgograd Regions of Russia. The study was conducted during vegetation period of 2012 from April till September. All the operations from importing the data to calculation of the output data were carried by eLEAF company and uploaded in Fieldlook web

  10. Using Computer Models to Explore Alternative Scenarios for Managing Limited Irrigation Water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop water stress due to low precipitation and high temperatures are the main limiting factors for agricultural production in the Great Plains. Corn is grown under either rainfed or irrigated regimes. Irrigation can improve corn profitability in this region, but over-irrigation accelerates depletio...

  11. Soil water measurement and thermal indices for center pivot irrigation scheduling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this two-year study, the relationship between irrigation scheduling using soil water measurements, and two thermal indices was investigated. One-half of a three-span center pivot irrigated field was planted to cotton in circular rows and irrigated with LEPA (low energy, precision application) dra...

  12. Sprinkler and surface irrigation effects on return flow water quality and quantity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major conservation practice in the Upper Snake-Rock (USR) watershed is the conversion from furrow irrigation to sprinkler irrigation. We compared the effect of irrigation system type on water quality and quantity at the watershed scale. Six small watersheds (150-700 ha) were identified with 5 to 7...

  13. Remote sensing based water-use efficiency evaluation in sub-surface irrigated wine grape vines

    NASA Astrophysics Data System (ADS)

    Zúñiga, Carlos Espinoza; Khot, Lav R.; Jacoby, Pete; Sankaran, Sindhuja

    2016-05-01

    Increased water demands have forced agriculture industry to investigate better irrigation management strategies in crop production. Efficient irrigation systems, improved irrigation scheduling, and selection of crop varieties with better water-use efficiencies can aid towards conserving water. In an ongoing experiment carried on in Red Mountain American Viticulture area near Benton City, Washington, subsurface drip irrigation treatments at 30, 60 and 90 cm depth, and 15, 30 and 60% irrigation were applied to satisfy evapotranspiration demand using pulse and continuous irrigation. These treatments were compared to continuous surface irrigation applied at 100% evapotranspiration demand. Thermal infrared and multispectral images were acquired using unmanned aerial vehicle during the growing season. Obtained results indicated no difference in yield among treatments (p<0.05), however there was statistical difference in leaf temperature comparing surface and subsurface irrigation (p<0.05). Normalized vegetation index obtained from the analysis of multispectral images showed statistical difference among treatments when surface and subsurface irrigation methods were compared. Similar differences in vegetation index values were observed, when irrigation rates were compared. Obtained results show the applicability of aerial thermal infrared and multispectral images to characterize plant responses to different irrigation treatments and use of such information in irrigation scheduling or high-throughput selection of water-use efficient crop varieties in plant breeding.

  14. Tap water nasal irrigation in adults with seasonal allergic rhinitis: a randomized double-blind study.

    PubMed

    Xiong, Min; Fu, Xiaoyan; Deng, Wenting; Lai, Huangwen; Yang, Chuanhong

    2014-06-01

    Saline nasal irrigation is effective in the treatment of seasonal allergic rhinitis, and sodium chloride itself has no antiallergic effects. The mechanism of saline nasal irrigation depends mainly on washing away allergens and inflammatory mediators induced by allergic reactions. Tap water has the same washing effects as saline. In this study, it was investigated if tap water nasal irrigation was effective in the treatment of seasonal allergic rhinitis. Sixty-four patients diagnosed with seasonal allergic rhinitis were enrolled. Patients were randomized to tap water nasal irrigation group and non-tap water nasal irrigation group for treatment. Patients of both groups were treated with desloratadine. Treatment outcomes were measured using allergic rhinitis Quality of Life (QoL) survey was completed at baseline and after 3 weeks of therapy. There were statistically significant differences in QoL scores between tap water nasal irrigation group and non-tap water nasal irrigation group. The tap water nasal irrigation group had better QoL scores than the non-tap water nasal irrigation group. Tap water nasal irrigation can be a valuable adjuvant therapy for patients with seasonal allergic rhinitis. PMID:24091560

  15. Seasonal simulation of water, salinity and nitrate dynamics under drip irrigated mandarin (Citrus reticulata) and assessing management options for drainage and nitrate leaching

    NASA Astrophysics Data System (ADS)

    Phogat, V.; Skewes, M. A.; Cox, J. W.; Sanderson, G.; Alam, J.; Šimůnek, J.

    2014-05-01

    and to reduce their leaching out of the crop root zone. Slightly higher nitrogen uptake (1.73 kg ha-1) was recorded when fertigation was applied second to last hour in an irrigation event, as compared to applying it earlier during an irrigation event. Similarly, a 20% reduction in irrigation and N application produced a pronounced reduction in drainage (28%) and N leaching (46.4%), but it also decreased plant N uptake by 15.8% and water uptake by 4.8%, and increased salinity by 25.8%, as compared to the normal practice. This management would adversely impact the sustainability of this expensive irrigation system. However, reducing only irrigation by 30% during the 2nd half of the crop season (January to August) reduced drainage and N leaching by 37.2% and 50.5%, respectively, and increased N uptake by 6.9%. Such management of irrigation would be quite promising for the sustainability of the entire system. It is concluded that judicious manipulations of irrigation and fertilizer applications can be helpful in designing drip irrigation schedules for perennial horticultural crops to achieve improved efficiency of irrigation and fertigation applications and reduced contamination of receiving water bodies.

  16. 25 CFR 171.215 - What if the elevation of my farm unit is too high to receive irrigation water?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... receive irrigation water? 171.215 Section 171.215 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.215 What if the elevation of my farm unit is too high to receive irrigation water? (a) We will not change our service...

  17. 25 CFR 171.215 - What if the elevation of my farm unit is too high to receive irrigation water?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... receive irrigation water? 171.215 Section 171.215 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.215 What if the elevation of my farm unit is too high to receive irrigation water? (a) We will not change our service...

  18. 25 CFR 171.215 - What if the elevation of my farm unit is too high to receive irrigation water?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... receive irrigation water? 171.215 Section 171.215 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.215 What if the elevation of my farm unit is too high to receive irrigation water? (a) We will not change our service...

  19. 25 CFR 171.215 - What if the elevation of my farm unit is too high to receive irrigation water?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... receive irrigation water? 171.215 Section 171.215 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.215 What if the elevation of my farm unit is too high to receive irrigation water? (a) We will not change our service...

  20. Quantifying and mapping China's crop yield gains from sustainable and unsustainable irrigation water use

    NASA Astrophysics Data System (ADS)

    Grogan, D. S.; Zhang, F.; Glidden, S.; Wisser, D.; Proussevitch, A. A.; Li, C.; Lammers, R. B.; Frolking, S.

    2012-12-01

    About 40 - 50% of China's cropland is irrigated. We used the DNDC model to predict crop yield for ~17 crop types involved in ~28 cropping systems across China, under zero and full irrigation for each county for 1981-2000. We estimate that yield increases due to irrigation range from 0 - 100%, depending on water deficits arising from local climate and weather conditions and crop types. We used gridded water balance simulations with the UNH WBM driven by MERRA weather reconstructions for 1981-2000 to compute demand for irrigation water, and the capacity of various sources to supply that demand in each grid cell. We estimate that approximately 15% - 20% of the water needed to fulfill the country's irrigation water demand must come from unsustainable sources such as fossil groundwater. Yields using only the sustainable irrigation water capacity are calculated by weighing the DNDC zero and full irrigation yields based on the water availability results of WBM for each grid cell. Restricting irrigation water use to only sustainable sources results in a national crop yield decrease of ~20%. Irrigation water demand, unsustainable water use, and crop yield gains due to irrigation all have significant spatial variation across China. These spatial variations show that irrigation water use - sustainable and unsustainable - results in significant crop yield gains in some regions, and little to no crop yield gains in other regions. Unsustainable water use for irrigation is concentrated in the highly populated and agriculturally valuable North China Plain region, particularly Hebei, Shandong and Henan Provinces. While current plans for the South-North Water Transfer could mitigate some of the water deficit we do not expect the projected transfers to adequately supply this region with sufficient water resources to supply both the people and crops sustainably.

  1. [Effect of climate change on rice irrigation water requirement in Songnen Plain, Northeast China].

    PubMed

    Huang, Zhi-gang; Wang, Xiao-li; Xiao, Ye; Yang, Fei; Wang, Chen-xi

    2015-01-01

    Based on meteorological data from China national weather stations and climate scenario grid data through regional climate model provided by National Climate Center, rice water requirement was calculated by using McCloud model and Penman-Monteith model combined with crop coefficient approach. Then the rice irrigation water requirement was estimated by water balance model, and the changes of rice water requirement were analyzed. The results indicated that either in historical period or in climate scenario, rice irrigation water requirement contour lines during the whole growth period and Lmid period decreased along southwest to northeast, and the same irrigation water requirement contour line moved north with decade alternation. Rice irrigation water requirement during the whole growth period increased fluctuantly with decade alternation at 44.2 mm . 10 a-1 in historical period and 19.9 mm . 10 a-1 in climate scenario. The increase in rice irrigation water requirement during the Lmid period with decade alternation was significant in historical period, but not significant in climate scenario. Contribution rate of climate change to rice irrigation water requirement would be fluctuantly increased with decade alternation in climate scenario. Compared with 1970s, contribution rates of climate change to rice irrigation water requirement were 23.6% in 2000s and 34.4% in 2040s, which increased 14.8 x 10(8) m3 irrigation water in 2000s and would increase 21.2 x 10(8) m3 irrigation water in 2040s. PMID:25985678

  2. Alternating irrigation water quality as a method to control solute concentrations and mass fluxes below irrigated fields: A numerical study

    NASA Astrophysics Data System (ADS)

    Russo, David

    2016-05-01

    The aim of the present numerical study was to extend the data-driven protocol for the control of soil salinity, to control chloride and nitrate concentrations and mass fluxes below agricultural fields irrigated with treated waste water (TWW). The protocol is based on alternating irrigation water quality between TWW and desalinized water (DSW), guided by solute concentrations at soil depth, zs. Two different schemes, the first requires measurements of soil solution concentrations of chloride and nitrate at zs, while, the second scheme requires only measurements of soil solution EC at zs, were investigated. For this purpose, 3-D numerical simulations of flow and transport were performed for variably saturated, spatially heterogeneous, flow domains located at two different field sites. The sites differ in crop type, irrigation method, and in their lithology; these differences, in turn, considerably affect the performance of the proposed schemes, expressed in terms of their ability to reduce solute concentrations that drained below the root zone. Results of the analyses suggest that the proposed data-driven schemes allow the use of low-quality water for irrigation, while minimizing the consumption of high-quality water to a level, which, for given climate, soil, crop, irrigation method, and water quality, may be determined by the allowable nitrate and chloride concentrations in the groundwater. The results of the present study indicate that with respect to the diminution of groundwater contamination by chloride and nitrate, the more data demanding, first scheme is superior the second scheme.

  3. Optimal crop selection and water allocation under limited water supply in irrigation

    NASA Astrophysics Data System (ADS)

    Stange, Peter; Grießbach, Ulrike; Schütze, Niels

    2015-04-01

    Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with limited water resources in irrigation systems, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand at the same time. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from optimized agronomic response on farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF). These functions take into account different soil types, crops and stochastically generated climate scenarios. The SCWPF's are used to compute the water demand considering different conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies.

  4. Soil Water in Relation to Irrigation, Uptake, and Potato Yield in a Humid Climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficiently controlling soil water content with irrigation is essential for water conservation and often improves potato yield. Volumetric soil water content ('v) in relation to irrigation, plant uptake, and yield in potato hills and replicated plots was studied to evaluate four water management opt...

  5. Sorghum response to foliar application of phosphorus and potassium with saline water irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing demand for fresh water resources for urban and industrial uses is leading to limited availability of better quality water for crop irrigation. Therefore, crop response to poor quality irrigation water (ex: saline water), and strategies to mitigate the negative effects of poor quality irri...

  6. Daily irrigation attenuates xylem abscisic acid concentration and increases leaf water potential of Pelargonium × hortorum compared with infrequent irrigation.

    PubMed

    Boyle, Richard K A; McAinsh, Martin; Dodd, Ian C

    2016-09-01

    The physiological response of plants to different irrigation frequencies may affect plant growth and water use efficiency (WUE; defined as shoot biomass/cumulative irrigation). Glasshouse-grown, containerized Pelargonium × hortorum BullsEye plants were irrigated either daily at 100% of plant evapotranspiration (ET) (well-watered; WW), or at 50% ET applied either daily [frequent deficit irrigation (FDI)] or cumulatively every 4 days [infrequent deficit irrigation (IDI)], for 24 days. Both FDI and IDI applied the same irrigation volume. Xylem sap was collected from the leaves, and stomatal conductance (gs ) and leaf water potential (Ψleaf ) measured every 2 days. As soil moisture decreased, gs decreased similarly under both FDI and IDI throughout the experiment. Ψleaf was maintained under IDI and increased under FDI. Leaf xylem abscisic acid (ABA) concentrations ([X-ABA]leaf ) increased as soil moisture decreased under both IDI and FDI, and was strongly correlated with decreased gs , but [X-ABA]leaf was attenuated under FDI throughout the experiment (at the same level of soil moisture as IDI plants). These physiological changes corresponded with differences in plant production. Both FDI and IDI decreased growth compared with WW plants, and by the end of the experiment, FDI plants also had a greater shoot fresh weight (18%) than IDI plants. Although both IDI and FDI had higher WUE than WW plants during the first 10 days of the experiment (when biomass did not differ between treatments), the deficit irrigation treatments had lower WUE than WW plants in the latter stages when growth was limited. Thus, ABA-induced stomatal closure may not always translate to increased WUE (at the whole plant level) if vegetative growth shows a similar sensitivity to soil drying, and growers must adapt their irrigation scheduling according to crop requirements. PMID:26910008

  7. Effects of shallow water table, salinity and frequency of irrigation water on the date palm water use

    NASA Astrophysics Data System (ADS)

    Askri, Brahim; Ahmed, Abdelkader T.; Abichou, Tarek; Bouhlila, Rachida

    2014-05-01

    In southern Tunisia oases, waterlogging, salinity, and water shortage represent serious threats to the sustainability of irrigated agriculture. Understanding the interaction between these problems and their effects on root water uptake is fundamental for suggesting possible options of improving land and water productivity. In this study, HYDRUS-1D model was used in a plot of farmland located in the Fatnassa oasis to investigate the effects of waterlogging, salinity, and water shortage on the date palm water use. The model was calibrated and validated using experimental data of sap flow density of a date palm, soil hydraulic properties, water table depth, and amount of irrigation water. The comparison between predicted and observed data for date palm transpiration rates was acceptable indicating that the model could well estimate water consumption of this tree crop. Scenario simulations were performed with different water table depths, and salinities and frequencies of irrigation water. The results show that the impacts of water table depth and irrigation frequency vary according to the season. In summer, high irrigation frequency and shallow groundwater are needed to maintain high water content and low salinity of the root-zone and therefore to increase the date palm transpiration rates. However, these factors have no significant effect in winter. The results also reveal that irrigation water salinity has no significant effect under shallow saline groundwater.

  8. Modeling as a tool for management of saline soils and irrigation waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Optimal management of saline soils and irrigation waters requires consideration of many interrelated factors including, climate, water applications and timing, water flow, plant water uptake, soil chemical reactions, plant response to salinity and solution composition, soil hydraulic properties and ...

  9. Agricultural-to-hydropower water transfers: sharing water and benefits in hydropower-irrigation systems

    NASA Astrophysics Data System (ADS)

    Tilmant, A.; Goor, Q.; Pinte, D.

    2009-03-01

    This paper presents a methodology to assess agricultural-to-hydropower water transfers in water resources systems where irrigation crop production and hydropower generation are the main economic activities. In many countries, water for crop irrigation is often considered as a static asset: irrigation water is usually allocated by a system of limited annual rights to use a prescribed volume of water. The opportunity cost (forgone benefits) of this static management approach may be important in river basins where large irrigation areas are present in the upstream reaches. Temporary reallocation of some (or all) of the irrigation water downstream to consumptive and/or non-consumptive users can increase the social benefits if the sum of the downstream productivities exceeds those of the upstream farmers whose entitlements are curtailed. However, such a dynamic allocation process will be socially acceptable if upstream farmers are compensated for increasing the availability of water downstream. This paper also presents a methodology to derive the individual contribution of downstream non-consumptive users, i.e. hydropower plants, to the financial compensation of upstream farmers. This dynamic management approach is illustrated with a cascade of multipurpose reservoirs in the Euphrates river basin. The analysis of simulation results reveals that, on average, the annual benefits obtained with the dynamic allocation process are 6% higher that those derived from a static allocation.

  10. Deep subsurface drip irrigation using coal-bed sodic water: Part I. Water and solute movement

    SciTech Connect

    Bern, Carleton R; Breit, George N; Healy, Richard W; Zupancic, John W; Hammack, Richard

    2013-02-01

    Water co-produced with coal-bed methane (CBM) in the semi-arid Powder River Basin of Wyoming and Montana commonly has relatively low salinity and high sodium adsorption ratios that can degrade soil permeability where used for irrigation. Nevertheless, a desire to derive beneficial use from the water and a need to dispose of large volumes of it have motivated the design of a deep subsurface drip irrigation (SDI) system capable of utilizing that water. Drip tubing is buried 92 cm deep and irrigates at a relatively constant rate year-round, while evapotranspiration by the alfalfa and grass crops grown is seasonal. We use field data from two sites and computer simulations of unsaturated flow to understand water and solute movements in the SDI fields. Combined irrigation and precipitation exceed potential evapotranspiration by 300–480 mm annually. Initially, excess water contributes to increased storage in the unsaturated zone, and then drainage causes cyclical rises in the water table beneath the fields. Native chloride and nitrate below 200 cm depth are leached by the drainage. Some CBM water moves upward from the drip tubing, drawn by drier conditions above. Chloride from CBM water accumulates there as root uptake removes the water. Year over year accumulations indicated by computer simulations illustrate that infiltration of precipitation water from the surface only partially leaches such accumulations away. Field data show that 7% and 27% of added chloride has accumulated above the drip tubing in an alfalfa and grass field, respectively, following 6 years of irrigation. Maximum chloride concentrations in the alfalfa field are around 45 cm depth but reach the surface in parts of the grass field, illustrating differences driven by crop physiology. Deep SDI offers a means of utilizing marginal quality irrigation waters and managing the accumulation of their associated solutes in the crop rooting zone.

  11. Deep subsurface drip irrigation using coal-bed sodic water: part I. water and solute movement

    USGS Publications Warehouse

    Bern, Carleton R.; Breit, George N.; Healy, Richard W.; Zupancic, John W.; Hammack, Richard

    2013-01-01

    Water co-produced with coal-bed methane (CBM) in the semi-arid Powder River Basin of Wyoming and Montana commonly has relatively low salinity and high sodium adsorption ratios that can degrade soil permeability where used for irrigation. Nevertheless, a desire to derive beneficial use from the water and a need to dispose of large volumes of it have motivated the design of a deep subsurface drip irrigation (SDI) system capable of utilizing that water. Drip tubing is buried 92 cm deep and irrigates at a relatively constant rate year-round, while evapotranspiration by the alfalfa and grass crops grown is seasonal. We use field data from two sites and computer simulations of unsaturated flow to understand water and solute movements in the SDI fields. Combined irrigation and precipitation exceed potential evapotranspiration by 300-480 mm annually. Initially, excess water contributes to increased storage in the unsaturated zone, and then drainage causes cyclical rises in the water table beneath the fields. Native chloride and nitrate below 200 cm depth are leached by the drainage. Some CBM water moves upward from the drip tubing, drawn by drier conditions above. Chloride from CBM water accumulates there as root uptake removes the water. Year over year accumulations indicated by computer simulations illustrate that infiltration of precipitation water from the surface only partially leaches such accumulations away. Field data show that 7% and 27% of added chloride has accumulated above the drip tubing in an alfalfa and grass field, respectively, following 6 years of irrigation. Maximum chloride concentrations in the alfalfa field are around 45 cm depth but reach the surface in parts of the grass field, illustrating differences driven by crop physiology. Deep SDI offers a means of utilizing marginal quality irrigation waters and managing the accumulation of their associated solutes in the crop rooting zone.

  12. Irrigation Management with Remote Sensing Techniques. Crop Water Requirements and Biophysical Indicators

    NASA Astrophysics Data System (ADS)

    Toureiro, Célia; Serralheiro, Ricardo

    2013-04-01

    Saving water in irrigated agriculture is increasingly relevant, as the irrigation sector is in many regions the biggest water consumer, but must be a sustainable activity. Therefore, the need urges for water use control methods and water resources planning. In irrigated agriculture, the right way for saving water is constituted by the increase of efficiency in water management. This work validates procedures and methodologies with remote sensing to determine the water availability in the soil at each moment and therefore the opportunity for the application of the water volume strictly necessary to optimize crop growth (irrigation opportunity and irrigation amount). The analysis applied to the Irrigation District of Divor, Évora, having used 7 experiment plots, which are areas watered by center-pivot systems, cultivated to corn. Data were determined from multispectral and infrared images of the cultivated surface obtained by satellite or by flying unmanned platform and integrated with parameters of the atmosphere and of the crops for calculating biophysical indicators and indices of water stress in the vegetation (NDVI, Kc, Kcb, CWSI). Therefore, evapotranspiration (ETc) was estimated, with which crop water requirement was calculated, with the opportunity and the amount of irrigation water to allocate. As this information is geographic referenced, maps can be prepared with GIS technology, describing water situation and the opportunity for watering crops. If the remote images are available with enough high spatial and temporal resolution, the frequent availability of maps can serve as a basis for a farmers irrigation advice system and for the regional irrigation authority to make decisions on the irrigation management at the regional scale. This can be a significant contribute to an efficient water management technology and a sustainable irrigated agriculture. Key-Words: Remote Sensing, Vegetation Index, Crop Coefficients, Water Balance

  13. Environmental Horticulture Program Guide.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide contains the standard environmental horticulture curriculum for technical institutes in Georgia. The curriculum encompasses the minimum competencies required for entry-level workers in the environmental horticulture field. The general information section contains the following: purpose and objectives; program description,…

  14. Competencies in Ornamental Horticulture

    ERIC Educational Resources Information Center

    Loewen, Curtis E.

    1974-01-01

    Based on the author's dissertation, this article pertains to the identification of competencies for ornamental horticulture workers in Oregon. Findings were based on interviews with 56 ornamental horticulture business employers regarding 100 competencies. The method used can serve as a model for obtaining occupational information to develop and…

  15. Horticultural Mechanics Competencies

    ERIC Educational Resources Information Center

    Shipley, W. Edward

    1974-01-01

    Ornamental horticulture teachers and managers of ornamental horticulture businesses were surveyed to determine which agricultural mechanics knowledges and skills are needed for entry-level employment in nursery, greenhouse, turf, and landscape management, which are common to the four areas, and the appropriate grade level at which they should be…

  16. Agriculture Education. Horticulture.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in ornamental horticulture. The guide presents units of study in the following areas: (1) horticulture and job opportunities, (2) preparing soil mixtures, (3) control, (4) plant propagation, (5) plant…

  17. Surface and subsurface water quality appraisal for irrigation.

    PubMed

    Isaac, R K; Khura, T K; Wurmbrand, J R

    2009-12-01

    Use of irrigation water available from various sources in agriculture is justified on agronomic and economic grounds but care must be taken to minimize its adverse environmental and health impacts. During the study 44 water samples, available from the various resources viz., canal, sewage pipe line, tube wells in confined aquifers, tube wells in unconfined aquifers, and wells in the Chaka block district Allahabad, were chemically analyzed to check its suitability for irrigation and to classify it according to amount of salts present. The analysis reveals that most of the samples were within the lower alkalinity limit (pH 7.17-8.42), except sewage water (pH 7.34-9.04). The electrical conductivity of the samples ranged from 0.26 to 1.37 millimhos/cm. Potassium, sodium, calcium, and phosphorus are all found to be in permissible range except one sample in the village Kuria in which Na percentage was found in doubtful category. The other parameters like sodium adsorption ratio, SAR (1.17-2.74), residual sodium carbonate, RSC (-4.46 to -1.07), and soluble sodium percentage, SSP (63.97-28.15) were also found below the permissible limit. PMID:19101814

  18. Water losses from irrigation canals evaluation: comparison among different methodologies

    NASA Astrophysics Data System (ADS)

    Clemente, Paolo; De Luca, Domenico Antonio; Antonella Dino, Giovanna; Lasagna, Manuela

    2013-04-01

    The research investigates the field methodologies to evaluate water losses from canals, in order to find a reliable method to identify and quantify them. This study was conducted in five canal lines in Piedmont, north-western Italy, different for hydraulic, morphological, geological and hydrogeological contexts (De Luca et alii, 2012). At a regional scale, Piedmont network consists of several tens of thousands km of irrigation canals. The loss of water due to seepage from irrigation canals constitutes a substantial part of the usable water. Irrigation canals placed in natural soil or fine and coarse sediments are characterized by water losses ranging from 20 % to more than 50 %. These losses cause economic, hydrogeological and environmental consequences: water losses evaluation from irrigation canals in the basis for the sustainable water resource use and management. First, hydrogeological and hydrological characterisation of the study area and of the bottom of the irrigation canals was carried out for every investigated canal, in order to evaluate the relationships between groundwater and stream water (eg. piezometric and hydrogeochemical survey campaigns, infiltrometry tests, penetrometric tests and electrical tomographies, soil characterizations from the bottom of investigated canals). The canals seepage rates were subsequently estimated using different methodologies: empirical formulas, inflow-outflow tests and double tracer tests. The empirical formulas applied for the study underestimated the real amount of the losses probably due to the scarce number of the considered variables. Then the canals seepage rates were evaluated employing inflow-outflow tests, considered the best tool by several authors. This method allows the determination of seepage quantities measuring inflow and outflow of a canal test reach either by instruments. The canal discharge was evaluated using a current meter. This method, even if easy to apply and practical, is not efficient

  19. Quantifying the Impacts of Irrigation Technology Adoption on Water Resources in the High Plains Aquifer, USA

    NASA Astrophysics Data System (ADS)

    Kendall, Anthony; Cotterman, Kayla; Hyndman, David

    2016-04-01

    Producers in key agricultural regions worldwide are contending with increasing demand while simultaneously managing declining water resources. The High Plains Aquifer (HPA) is the largest aquifer system in the United States, and supplied most of the water to irrigate 6 million hectares in 2012. Water levels in the central and southern sections of the aquifer have steadily declined, as groundwater recharge in this semi-arid region is insufficient to meet water demands. Individual irrigators have responded to these declines by moving from less efficient irrigation technologies to those that apply water more precisely. Yet, these newer technologies have also allowed for water to be pumped from lower-yielding wells, thus extending the life of any given well and allowing drawdown to continue. Here we use a dataset of the annual irrigation technology choices from every irrigator in the state of Kansas, located in the Central High Plains. This irrigation data, along with remotely-sensed Leaf Area Index, crop choice, and irrigated area, drives a coupled surface/groundwater simulation created using the Landscape Hydrology Model (LHM) to examine the impacts of changing irrigation technology on the regional water cycle, and water levels in the HPA. The model is applied to simulate cases in which no irrigation technology change had occurred, and complete adoption of newer technologies to better understand impacts of management choices on regional water resources.

  20. Water quality, pesticide occurrence, and effects of irrigation with reclaimed water at golf courses in Florida

    USGS Publications Warehouse

    Swancar, Amy

    1996-01-01

    Reuse of treated wastewater for golf course irrigation is an increasingly popular water management option in Florida, where growth has put stress on potable water supplies. Surface water, ground water, and irrigation water were sampled at three pairs of golf courses quarterly for one year to determine if pesticides were present, and the effect of irrigation with treated effluent on ground-water quality, with an emphasis on interactions of effluent with pesticides. In addition to the six paired golf courses, which were in central Florida, ground water was sampled for pesticides and other constituents at three more golf courses in other parts of the State. This study was the first to analyze water samples from Florida golf courses for a broad range of pesticides. Statistical methods based on the percentage of data above detection limits were used to determine the effects of irrigation with reclaimed water on ground-water quality. Shallow ground water at golf courses irrigated with treated effluent has higher concentrations of chloride, lower concentrations of bicarbonate, and lower pH than ground water at golf courses irrigated with water from carbonate aquifers. There were no statistically significant differences in nutrient concentrations in ground water between paired golf courses grouped by irrigation water type at a 95 percent confidence level. The number of wells where pesticides occurred was significantly higher at the paired golf courses using ground water for irrigation than at ones using reclaimed water. However, the limited occurrences of individual pesticides in ground water make it difficult to correlate differences in irrigation- water quality with pesticide migration to the water table. At some of the golf courses, increased pesticide occurrences may be associated with higher irrigation rates, the presence of well-drained soils, and shallow depths to the surficial aquifer. Pesticides used by golf courses for turf grass maintenance were detected in

  1. Field measurements of water and nitrogen losses under irrigated maize

    NASA Astrophysics Data System (ADS)

    Kengni, L.; Vachaud, G.; Thony, J. L.; Laty, R.; Garino, B.; Casabianca, H.; Jame, P.; Viscogliosi, R.

    1994-10-01

    An intensive multidisciplinary experiment has been conducted over several years at La Côte Saint-André, near Grenoble, France. The major objective is to determine an optimal fertilizer application scheme for an irrigated agricultural system. Such a scheme would not degrade the quality of the environment, and yet would maintain a profitable level of crop production. This study is explicitly related to the cultivation of irrigated maize, a major crop in the area. The various terms of the water balance (consumption, drainage, soil storage) and of the nitrogen cycle (mineralization, plant uptake, leaching) were obtained from intensive monitoring in the upper layer of the 0.8 m of soil which corresponds to the root zone of the crop. This entailed the combined use of a neutron moisture meter, tensiometers and soil suction cups. To determine the specific effects of fertilization and crop growth, there were different treatments. These corresponded to a traditional fertilizer application of 260 kg N ha -1, no fertilization, and bare soil, carried out within an area of approximately 2 ha. Several sites were instrumented on each treatment, one of them being specifically for the application and the monitoring of 15N-tagged fertilizer. The results have shown that, in terms of the water balance, irrigation water management is extremely efficient, as drainage losses under the maize culture are negligible during the crop cycle. The situation is totally different, however, during the intercrop period (October-April), owing to rainfall. Then the soil is left bare and evaporation is very small, and now the drainage corresponds to about 90% of total inputs from precipitation. In terms of the nitrogen cycle, the results showed clearly that up to 150 kg N ha -1 was produced by mineralization in the soil. Nitrogen leaching beyond the root zone during the crop cycle is negligible, regardless of the rate of fertilizer application, as a result of the very small amount of drainage, despite

  2. Evaluating regional water scarcity: Irrigated crop water budgets for groundwater management in the Wisconsin Central Sands

    NASA Astrophysics Data System (ADS)

    Nocco, M. A.; Kucharik, C. J.; Kraft, G.

    2013-12-01

    Regional water scarcity dilemmas between agricultural and aquatic land users pervade the humid northern lake states of Wisconsin, Minnesota, and Michigan, where agricultural irrigation relies on groundwater drawn from shallow aquifers. As these aquifers have strong connectivity to surface waters, irrigation lowers water levels in lakes and wetlands and reduces stream discharges. Irrigation expansion has cultivated a 60-year water scarcity dilemma in The Wisconsin Central Sands, the largest irrigated region in the humid northern lake states, dedicated to potato, maize, and processing vegetable production. Irrigation has depleted Wisconsin Central Sands surface waters, lowering levels in some lakes by over 2 m and drying some coldwater trout streams. Aquatic ecosystems, property values, and recreational uses in some surface waters have been devastated. While the causal link between pumping and surface water stress is established, understanding crop-mediated processes, such as the timing and magnitude of groundwater consumption by evapotranspiration (ET) and groundwater recharge, will be useful in management of groundwater, irrigated cropping systems, and surface water health. Previous modeling and field efforts have compared irrigated crop water use to a natural reference condition on a net annual basis. As a result, we presently understand that for irrigated potatoes and maize, the average annual ET is greater and therefore, the average annual recharge is less than rainfed row crops, grasslands, and both coniferous and deciduous forests. However, we have a limited understanding of the magnitude and timing of ET and recharge from irrigated cropping systems on shorter time scales that proceed with the annual cropping cycle (i.e. planting, full canopy, harvest, residue cover). We seek to understand the spatiotemporal variability of crop water budgets and associated water scarcity in the Wisconsin Central Sands through detailed measurements of drainage (potential

  3. Holistic irrigation water management approach based on stochastic soil water dynamics

    NASA Astrophysics Data System (ADS)

    Alizadeh, H.; Mousavi, S. J.

    2012-04-01

    Appreciating the essential gap between fundamental unsaturated zone transport processes and soil and water management due to low effectiveness of some of monitoring and modeling approaches, this study presents a mathematical programming model for irrigation management optimization based on stochastic soil water dynamics. The model is a nonlinear non-convex program with an economic objective function to address water productivity and profitability aspects in irrigation management through optimizing irrigation policy. Utilizing an optimization-simulation method, the model includes an eco-hydrological integrated simulation model consisting of an explicit stochastic module of soil moisture dynamics in the crop-root zone with shallow water table effects, a conceptual root-zone salt balance module, and the FAO crop yield module. Interdependent hydrology of soil unsaturated and saturated zones is treated in a semi-analytical approach in two steps. At first step analytical expressions are derived for the expected values of crop yield, total water requirement and soil water balance components assuming fixed level for shallow water table, while numerical Newton-Raphson procedure is employed at the second step to modify value of shallow water table level. Particle Swarm Optimization (PSO) algorithm, combined with the eco-hydrological simulation model, has been used to solve the non-convex program. Benefiting from semi-analytical framework of the simulation model, the optimization-simulation method with significantly better computational performance compared to a numerical Mote-Carlo simulation-based technique has led to an effective irrigation management tool that can contribute to bridging the gap between vadose zone theory and water management practice. In addition to precisely assessing the most influential processes at a growing season time scale, one can use the developed model in large scale systems such as irrigation districts and agricultural catchments. Accordingly

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Economic impacts on irrigated agriculture of water conservation programs in drought

    NASA Astrophysics Data System (ADS)

    Ward, Frank A.

    2014-01-01

    This study analyzes vulnerability, impacts, and adaptability by irrigation to drought.It accounts for economic incentives affecting choices on irrigation technology, crop mix, and water sources.When surface water supplies fall, farmers increase pumping, even when pumping raises production costs.Conservation program subsidies raise the value of food production but can increase crop water depletions.

  6. Characterizing irrigation water requirements for rice production from the Arkansas Rice Research Verification Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated rice irrigation water use in the University of Arkansas Rice Research Verification Program between the years of 2003 and 2011. Irrigation water use averaged 747 mm (29.4 inches) over the nine years. A significant 40% water savings was reported for rice grown under a zero gr...

  7. Intelligent irrigation performance: evaluation and quantifying its ability for conserving water in arid region

    NASA Astrophysics Data System (ADS)

    Al-Ghobari, Hussein M.; Mohammad, Fawzi S.

    2011-12-01

    Intelligent irrigation technologies have been developed in recent years to apply irrigation to turf and landscape plants. These technologies are an evapotranspiration (ET)-based irrigation controller, which calculates ET for local microclimate. Then, the controller creates a program for loading and communicating automatically with drip or sprinkler system controllers. The main objective of this study was to evaluate the effectiveness of the new ET sensors in ability to irrigate agricultural crops and to conserve water use for crop in arid climatic conditions. This paper presents the case for water conservation using intelligent irrigation system (IIS) application technology. The IIS for automating irrigation scheduling was implemented and tested with sprinkle and drip irrigation systems to irrigate wheat and tomato crops. Another irrigation scheduling system was also installed and operated as another treatment, which is based on weather data that retrieved from an automatic weather station. This irrigation control system was running in parallel to the former system (IIS) to be control experiments for comparison purposes. However, this article discusses the implementation of IIS, its installation, testing and calibration of various components. The experiments conducted for one growing season 2009-2010 and the results were represented and discussed herein. Data from all plots were analyzed, which were including soil water status, water consumption, and crop yield. The initial results indicate that up to 25% water saving by intelligent irrigation compared to control method, while maintaining competing yield. Results show that the crop evapotranspiration values for control experiments were higher than that of ET-System in consistent trend during whole growth season. The analysis points out that the values of the two treatments were somewhat close to each other's only in the initial development stages. Generally, the ET-System, with some modification was precise in

  8. Catchment scale analysis on river-return ratio of irrigation water from densely developed paddy areas

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Masumoto, T.; Horikawa, N.; Kudo, R.; Minakawa, H.; Nawa, N.

    2013-12-01

    Irrigation in Japan is predominantly used for rice cultivation, and it accounts for 70% of total water withdrawal. Water loss, which is attributable to nature of open channel irrigation system and percolation from fields, leads to relatively low irrigation efficiencies compared with ones for upland crops. However, because part of water gradually returns to rivers (river-return flow), it contributes to stable water use in downstream. This study investigated how irrigation water circulates and returns to rivers, and quantified a ratio of river-return flow to irrigation intake for an irrigation area (river-return ratio). One difficulty in river-return flow analysis lies in the fact that two types of flow pathways exist in an irrigation area; natural rivers that drain water from the areas, and channel networks whose directions do not necessarily coincide with river directions. In addition, outflux from irrigation area is consisted of water from different sources, such as water loss during water allocation, rainfall, irrigation, and influx from adjacent upstream areas. To cope with such difficulties, we used a grid-based distributed water circulation model that represents both catchment scale hydrological cycles and water flows related to irrigation channel network. The model calculates water flow for irrigation networks based on a GIS database of water use facilities. The model also incorporates operation rules for facilities and field level water management. Using the modeled river network, we first identify grid-cells where influx and outflux occurs across boundaries of irrigation areas. Then, to eliminate the effect of influx from adjacent upstream areas, we subtract influx from outflux. This makes us to capture outflux that purely originates in rainfall and irrigation within an irrigated area. Next, we separate the amount of outflux that originates in irrigation from the total amount of outflux. As residence time of each flow pathway had not been clarified yet, we

  9. Uptake of antibiotics from irrigation water by plants.

    PubMed

    Azanu, David; Mortey, Christiana; Darko, Godfred; Weisser, Johan Juhl; Styrishave, Bjarne; Abaidoo, Robert Clement

    2016-08-01

    The capacity of carrot (Daucus corota L.) and lettuce (Lactuca sativa L.), two plants that are usually eaten raw, to uptake tetracycline and amoxicillin (two commonly used antibiotics) from irrigated water was investigated in order to assess the indirect human exposure to antibiotics through consumption of uncooked vegetables. Antibiotics in potted plants that had been irrigated with known concentrations of the antibiotics were extracted using accelerated solvent extraction and analyzed on a liquid chromatograph-tandem mass spectrometer. The plants absorbed the antibiotics from water in all tested concentrations of 0.1-15 mg L(-1). Tetracycline was detected in all plant samples, at concentrations ranging from 4.4 to 28.3 ng/g in lettuce and 12.0-36.8 ng g(-1) fresh weight in carrots. Amoxicillin showed absorption with concentrations ranging from 13.7 ng g(-1) to 45.2 ng g(-1) for the plant samples. The mean concentration of amoxicillin (27.1 ng g(-1)) in all the samples was significantly higher (p = 0.04) than that of tetracycline (20.2 ng g(-1)) indicating higher uptake of amoxicillin than tetracycline. This suggests that the low antibiotic concentrations found in plants could be important for causing antibiotics resistance when these levels are consumed. PMID:27213239

  10. Theme: Staying Current--Horticulture.

    ERIC Educational Resources Information Center

    Shry, Carroll L., Jr.; And Others

    1986-01-01

    This theme issue on staying current in horticulture includes articles on sex equity in horticulture, Future Farmers of America, career opportunities in horticulture, staying current with your school district's needs, staying current in horticulture instruction, staying current with landscape trade associations, emphasizing the basics in vocational…

  11. LOWER PAYETTE RIVER, IDAHO AGRICULTURE IRRIGATION WATER RETURN STUDY AND GROUND WATER EVALUATION, 1992-1993

    EPA Science Inventory

    This report covers the final 17 miles of the Payette River (17050112) and 32,000 acres of irrigated cropland referred to as the Lower Payette State Agricultural Water Quality Project. An in-depth surface and ground water monitoring effort was initiated in June 1992 and completed...

  12. Water use and water productivity of sugarbeet, malt barley and potato as affected by irrigation frequency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Successful irrigation management is one of the most important agronomic practices for achieving profitable yield and maximizing crop water productivity (CWP) while maintaining environmental quality by minimizing water losses to runoff and deep drainage. This study was conducted to compare the influe...

  13. Greenhouse gas emissions, irrigation water use, and arsenic concentrations; a common thread in rice water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice has historically been grown as a flooded crop in the United States. As competition for water resources has grown, there is interest in reducing water use in rice production so as to maintain a viable and sustainable rice industry into the future. An irrigation study was established in 2011 at ...

  14. Water Stress & Biomass Monitoring and SWAP Modeling of Irrigated Crops in Saratov Region of Russia

    NASA Astrophysics Data System (ADS)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2016-04-01

    Development of modern irrigation technologies are balanced between the need to maximize production and the need to minimize water use which provides harmonious interaction of irrigated systems with closely-spaced environment. Thus requires an understanding of complex interrelationships between landscape and underground of irrigated and adjacent areas in present and future conditions aiming to minimize development of negative scenarios. In this way in each irrigated areas a combination of specific factors and drivers must be recognized and evaluated. Much can be obtained by improving the efficiency use of water applied for irrigation. Modern RS monitoring technologies offers the opportunity to develop and implement an effective irrigation control program permitting today to increase efficiency of irrigation water use. These technologies provide parameters with both high temporal and adequate spatial needed to monitor agrohydrological parameters of irrigated agricultural crops. Combination of these parameters with meteorological and biophysical parameters can be used to estimate crop water stress defined as ratio between actual (ETa) and potential (ETc) evapotranspiration. Aggregation of actual values of crop water stress with biomass (yield) data predicted by agrohydrological model based on weather forecasting and scenarios of irrigation water application may be used for indication of both rational timing and amount of irrigation water allocation. This type of analysis facilitating an efficient water management can be easily extended to irrigated areas by developing maps of water efficiency application serving as an irrigation advice system for farmers at his fields and as a decision support tool for the authorities on the large perimeter irrigation management. This contribution aims to communicate an illustrative explanation about the practical application of a data combination of agrohydrological modeling and ground & space based monitoring. For this aim some

  15. Drainage water quality and end-member identification in La Violada irrigation district (Spain)

    NASA Astrophysics Data System (ADS)

    Isidoro, D.; Quílez, D.; Aragüés, R.

    2010-03-01

    SummaryThe identification of the different components in a water course is required to individualize and assess the actual contribution of irrigated agriculture to the pollution of the water course. This paper aimed at identifying and assessing the composition of the end-members in La Violada irrigation district (VID) and establishing a statistical procedure to reduce the sampling effort needed to establish drainage water quality. The quality of irrigation water, groundwater, and irrigated-land drainage water in VID was monitored during three hydrologic years to identify the components of flow in La Violada Gully, the natural exit course of VID. A network of sampling points in the secondary ditches and main drains of VID allowed identifying and separating those collecting irrigated-land drainage waters from those conveying high proportions of irrigation waters. Three end-member flows were identified in La Violada Gully during the irrigation season: (a) irrigation water arising from tail-waters, leakages and spills from the irrigation canals, very low in salts; (b) groundwater originating from the non-irrigated upper reaches of La Violada Gully watershed, high in Cl - and Na +; and (c) VID drainage water, high in SO42- and Ca 2+. The overall VID drainage water quality was accurately assessed through a simplified sampling scheme of only four sampling points that produced low errors of 0.1 dS/m for EC and 0.1 mmol c/L for Cl -. The separation of La Violada Gully flow in these three components is essential for estimating the actual contribution of irrigation in VID to the salt and nitrogen loads in La Violada Gully.

  16. Economics of Irrigation Water Mixing Within a Farm Framework

    NASA Astrophysics Data System (ADS)

    Feinerman, E.; Yaron, D.

    1983-04-01

    Linear programing models, deterministic in the short run and stochastic (random rainfall) in the long run, aimed at guiding annual decision making with regard to crop mix and saline irrigation water mixing from various sources within a farm framework, are presented. The short-run model incorporates the physical, biological, and economic relationships involved in one endogenous system and enables an in depth analysis of them but is limited to a single year. The long-run model considers the effects of the short-run decisions on the future but several relationships are incorporated exogenously. The short run model's results are utilized for the determination of some of these predetermined relationships. The models are applied to a potential farm situation in southern Israel. The results provide priorities in the allocation of water and soil plots of varying salinity levels and empirical estimates of the shadow prices and the rates of substitution between the limited resources.

  17. Effects of climate and irrigation changes on the water balance of a Mediterranean catchment

    NASA Astrophysics Data System (ADS)

    von Gunten, Diane; Wöhling, Thomas; Haslauer, Claus; Cirpka, Olaf

    2015-04-01

    Climate change will strongly impact the water cycle of Mediterranean catchments as a result of the changes in precipitation patterns and increased temperature. However, effects of climate change are difficult to predict with precision and are often influenced by land-use or water management choices. In agricultural catchments, irrigation is of particular interest because of its importance for cultivation in semi-arid climate and because of its strong impacts on hydrological processes. Interactions between irrigation and climate change impacts are likely to be important and should be considered when studying the future of a catchment. However, they are still difficult to quantify. A better understanding of the differences in climate-change sensitivity between irrigated and non-irrigated catchments would allow a finer description of local climate change effects. In this study, we compared the impacts of climate change in various irrigation scenarios, including a scenario without irrigation. Our case study was a relatively small catchment (about 7.5km2) in north-east Spain, called the Lerma catchment. This catchment was not irrigated prior to 2006, but 54% of its surface is now used for irrigated agriculture. This transition to irrigated agriculture was closely monitored and data on hydraulic heads, discharge and daily irrigation volume are available. Based on these measurements, a coupled surface-subsurface model of the catchment was developed using the pde-based model HydroGeoSphere. The model performs well for both irrigated and non-irrigated periods. Future climate was predicted using four regional climate models from the ENSEMBLE project (P.van der Linden and J.Mitchell, ENSEMBLES: Climate Change and its Impacts [...], Met Office Hadley Center, 2009) and two downscaling methods, including one based on a weather generator. Four irrigation scenarios, based on projected potential evapotranspiration changes, were compared. Our results show a shift in the climate

  18. Irrigation: Erosion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation is essential for global food production. However, irrigation erosion can limit the ability of irrigation systems to reliably produce food and fiber in the future. The factors affecting soil erosion from irrigation are the same as rainfall—water detaches and transports sediment. However, t...

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

    PubMed Central

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

    2013-01-01

    Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp.) and that the transformities of irrigation water and rice as the systems' products (1.72E + 05 sej/J and 1.42E + 05 sej/J, resp.; sej/J = solar emjoules per joule) represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR), and environmental sustainability index (ESI). The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water. PMID:24082852

  20. Irrigation scheduling by ET and soil water sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation scheduling is the process of deciding when, where and how much to irrigate, usually with the goal of optimizing economic return on investment in land, equipment, inputs and personnel. This hour-long seminar presents methods of irrigation scheduling based, on the one hand on estimates of t...

  1. Emergy evaluation of a pumping irrigation water production system in China

    NASA Astrophysics Data System (ADS)

    Chen, Dan; Luo, Zhaohui; Webber, Michael; Chen, Jing; Wang, Weiguang

    2014-03-01

    The emergy concept was used to evaluate a pumping irrigation water production system in China. A framework for emergy evaluation of the significance of irrigation water and its production process was developed. The results show that the irrigation water saved has the highest emergy value (8.73E + 05 sej·J-1), followed by the irrigation water supplied to farmlands (1.72E + 05 sej·J-1), the pumped water (4.81E + 04 sej·J-1), with the lowest value shown from water taken from the local river (3.72E + 04 sej·J-1). The major contributions to the emergy needed for production are the inputs of soil and water. This production system could contribute to the irrigated agriculture and economy, according to several calculated emergy indices: emergy yield ratio ( EYR), emergy investment ratio ( EIR), environmental load ratio ( ELR), and environmental sustainability index ( ESI). The comparative analysis shows that the emergy theory and method, different from the conventional monetary-based analysis, could be used to evaluate irrigation water and its production process in terms of the biophysical account. Additional emergy evaluations should be completed on different types of water production and irrigated agricultural systems to provide adequate guidelines for the sustainability of irrigation development.

  2. Ground water for irrigation in the Viking Basin, west-central Minnesota

    USGS Publications Warehouse

    McBride, M.S.

    1975-01-01

    The Viking Basin consists of six glacial outwash areas in Douglas, Ottertail, and Todd Counties, west-central Minnesota. Total area is 340 square miles (880 square kilometres). Soils are sandy and excessively well-drained. Crops grown on the outwash would benefit from supplemental irrigation. Irrigation supplies can be obtained from wells in the surface outwash aquifer in significant parts of the large outwash areas near Carlos and Parkers Prairie and the small outwash area near Clotho. Irrigation supplies are unlikely in the outwash areas near Alexandria, Urbank, and Rose City. Major use of ground water for irrigation may lower ground-water levels sufficiently to affect lake and marsh levels and streamflow out of the irrigation areas. Water from the outwash is of excellent chemical quality for irrigation.

  3. Identification of Extended-Spectrum β-Lactamases Escherichia coli Strains Isolated from Market Garden Products and Irrigation Water in Benin

    PubMed Central

    Moussé, Wassiyath; Sina, Haziz; Baba-Moussa, Farid; Noumavo, Pacôme A.; Agbodjato, Nadège A.; Adjanohoun, Adolphe; Baba-Moussa, Lamine

    2015-01-01

    The present study aimed at biochemical and molecular characterization of Escherichia coli strains isolated from horticultural products and irrigation water of Cotonou. The samples were collected from 12 market gardeners of 4 different sites. Rapid' E. coli medium was used for identification of E. coli strains and the antimicrobial susceptibility was performed by the agar disk diffusion method. The β-lactamases production was sought by the liquid acidimetric method. The genes coding for β-lactamases and toxins were identified by PCR method. The results revealed that about 34.95% of the analyzed samples were contaminated by E. coli. Cabbages were the most contaminated by E. coli (28.26%) in dry season. All isolated strains were resistant to amoxicillin. The penicillinase producing E. coli carried blaTEM (67.50%), blaSHV (10%), and blaCTX-M (22.50%) genes. The study revealed that the resistance genes such as SLTI (35.71%), SLTII (35.71%), ETEC (7.15%), and VTEC (21.43%) were carried. Openly to the found results and considering the importance of horticultural products in Beninese food habits, it is important to put several strategies aiming at a sanitary security by surveillance and sensitization of all the actors on the risks of some practices. PMID:26770972

  4. Identification of Extended-Spectrum β-Lactamases Escherichia coli Strains Isolated from Market Garden Products and Irrigation Water in Benin.

    PubMed

    Moussé, Wassiyath; Sina, Haziz; Baba-Moussa, Farid; Noumavo, Pacôme A; Agbodjato, Nadège A; Adjanohoun, Adolphe; Baba-Moussa, Lamine

    2015-01-01

    The present study aimed at biochemical and molecular characterization of Escherichia coli strains isolated from horticultural products and irrigation water of Cotonou. The samples were collected from 12 market gardeners of 4 different sites. Rapid' E. coli medium was used for identification of E. coli strains and the antimicrobial susceptibility was performed by the agar disk diffusion method. The β-lactamases production was sought by the liquid acidimetric method. The genes coding for β-lactamases and toxins were identified by PCR method. The results revealed that about 34.95% of the analyzed samples were contaminated by E. coli. Cabbages were the most contaminated by E. coli (28.26%) in dry season. All isolated strains were resistant to amoxicillin. The penicillinase producing E. coli carried blaTEM (67.50%), blaSHV (10%), and blaCTX-M (22.50%) genes. The study revealed that the resistance genes such as SLTI (35.71%), SLTII (35.71%), ETEC (7.15%), and VTEC (21.43%) were carried. Openly to the found results and considering the importance of horticultural products in Beninese food habits, it is important to put several strategies aiming at a sanitary security by surveillance and sensitization of all the actors on the risks of some practices. PMID:26770972

  5. Forest Irrigation of Tritiated Water: A Proven Tritiated Water Management Tool - 13357

    SciTech Connect

    Prater, Phil; Blount, Gerald; Kmetz, Thomas; Vangelas, Karen

    2013-07-01

    Tritium releases from the Old Radioactive Waste Burial Ground (ORWBG) at the SRS in South Carolina has impacted groundwater and surface water. Tritiated groundwater plumes discharge into Fourmile Branch which is a small tributary of the Savannah River, a regional water resource. Taking advantage of the groundwater flow paths and the local topography a water collection and irrigation system was constructed and has been used at the SRS for over a decade to reduce these tritiated water releases to Fourmile Branch. The tritiated water is transferred to the atmosphere by evaporation from the pond surface, and after irrigation, wetted surface evaporation and evapotranspiration through the forest vegetation. Over the last decade SRS has irrigated over 120,000,000 gallons of tritiated water, which diverted over 6000 curies away from Fourmile Branch and the Savannah River. The system has been effective in reducing the flux of tritiated groundwater by approximately 70%. Mass balance studies of tritium in the forest soils before operations and over the last decade indicate that approximately 90% of the tritiated water that is irrigated is transferred to the atmosphere. Dose studies indicate that exposure to site workers and offsite maximally exposed individual is very low, approximately 6 mrem/year and 0.004 mrem/year, respectively. To consistently meet the flux reduction goal of tritium into Fourmile Branch optimization activities are proposed. These efforts will increase irrigation capacity and area. An additional 17 acres are proposed for an expansion of the area to be irrigated and a planting of approximately 40 acres of pine forest plantations is underway to expand irrigation capacity. Co-mingled with the tritiated groundwater are low concentrations of chlorinated volatile organic compounds (cVOCs), and 1,4-dioxane. Research studies and SRS field data indicate the forest irrigation system may have an added benefit of reducing the mass of these co-contaminants via

  6. Forest Irrigation Of Tritiated Water: A Proven Tritiated Water Management Tool

    SciTech Connect

    Vangelas, Karen; Blount, Gerald; Kmetz, Thomas; Prater, Phil

    2012-11-08

    Tritium releases from the Old Radioactive Waste Burial Ground (ORWBG) at the SRS in South Carolina has impacted groundwater and surface water. Tritiated groundwater plumes discharge into Fourmile Branch which is a small tributary of the Savannah River, a regional water resource. Taking advantage of the groundwater flow paths and the local topography a water collection and irrigation system was constructed and has been used at the SRS for over a decade to reduce these tritiated water releases to Fourmile Branch. The tritiated water is transferred to the atmosphere by evaporation from the pond surface, and after irrigation, wetted surface evaporation and evapotranspiration through the forest vegetation. Over the last decade SRS has irrigated over 120,000,000 gallons of tritiated water, which diverted over 6000 curies away from Fourmile Branch and the Savannah River. The system has been effective in reducing the flux of tritiated groundwater by approximately 70%. Mass balance studies of tritium in the forest soils before operations and over the last decade indicate that approximately 90% of the tritiated water that is irrigated is transferred to the atmosphere. Dose studies indicate that exposure to site workers and offsite maximally exposed individual is very low, approximately 6 mrem/year and 0.004 mrem/year, respectively. To consistently meet the flux reduction goal of tritium into Fourmile Branch optimization activities are proposed. These efforts will increase irrigation capacity and area. An additional 17 acres are proposed for an expansion of the area to be irrigated and a planting of approximately 40 acres of pine forest plantations is underway to expand irrigation capacity. Co-mingled with the tritiated groundwater are low concentrations of chlorinated volatile organic compounds (cVOCs), and 1,4-dioxane. Research studies and SRS field data indicate the forest irrigation system may have an added benefit of reducing the mass of these co-contaminants via

  7. Reuse potential of laundry greywater for irrigation based on growth, water and nutrient use of tomato

    NASA Astrophysics Data System (ADS)

    Misra, R. K.; Patel, J. H.; Baxi, V. R.

    2010-05-01

    SummaryGreywater is considered as a valuable resource with a high reuse potential for irrigation of household lawns and gardens. However, there are possibilities of surfactant and sodium accumulation in soil from reuse of greywater which may affect agricultural productivity and environmental sustainability adversely. We conducted a glasshouse experiment to examine variation in growth, water and nutrient use of tomato ( Lycopersicon esculentum Mill. cv. Grosse Lisse) using tap water (TW), laundry greywater (GW) and solutions of low and high concentration of a detergent surfactant (LC and HC, respectively) as irrigation treatments. Each treatment was replicated five times using a randomised block design. Measurements throughout the experiment showed greywater to be significantly more alkaline and saline than the other types of irrigation water. Although all plants received 16 irrigations over a period of 9 weeks until flowering, there were little or no significant effects of irrigation treatments on plant growth. Soil water retention following irrigation reduced significantly when plants were irrigated with GW or surfactant solutions on only three of 12 occasions. On one occasion, water use measured as evapotranspiration (ET) with GW irrigation was similar to TW, but it was significantly higher than the plants receiving HC irrigation. At harvest, various components of plant biomass and leaf area for GW irrigated plants were found to be similar or significantly higher than the TW irrigated plants with a common trend of GW ⩾ TW > LC ⩾ HC. Whole-plant concentration was measured for 12 essential plant nutrients (N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, Mo and B) and Na (often considered as a beneficial nutrient). Irrigation treatments affected the concentration of four nutrients (P, Fe, Zn and Na) and uptake of seven nutrients (P, K, Ca, Mg, Na, Fe and B) significantly. Uptake of these seven nutrients by tomato was generally in the order GW ⩾ TW > HC ⩾ LC. GW

  8. Quantifying corn yield and water use efficiency in response to growth-stage based irrigation scheduling and seasonal water availability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A calibrated agricultural system model can help optimize limited irrigation water for higher crop yield and water use efficiency (WUE) across a wide range of climate conditions. In this study, the Root Zone Water Quality Model (RZWQM2) was calibrated for corn growth under a range of irrigation treat...

  9. Models for root water uptake under deficit irrigation

    NASA Astrophysics Data System (ADS)

    Lazarovitch, Naftali; Krounbi, Leilah; Simunek, Jirka

    2010-05-01

    Modern agriculture, with its dependence on irrigation, fertilizers, and pesticide application, contributes significantly to the water and solute influx through the soil into the groundwater, specifically in arid areas. The quality and quantity of this water as it passes through the vadose zone is influenced primarily by plant roots. Root water uptake is a function of both a physical root parameter, commonly referred to as the root length density, and the soil water status. The location of maximum water uptake in a homogenous soil profile of uniform water content and hydraulic conductivity occurs in the soil layer containing the largest root length density. Under field conditions, in a drying soil, plants are both subject to, and the source of, great spatial variability in the soil water content. The upper soil layers containing the bulk of the root zone are usually the most water depleted, while the deeper regions of the soil profile containing fewer roots are wetter. Changes in the physiological functioning of plants have been shown to result from extended periods of water stress, but the short term effects of water stress on root water uptake are less well understood. While plants can minimize transpiration and the resulting growth rates under limiting conditions to conserve water, many plants maintain a constant potential transpiration rate long after the commencement of the drying process. Compensatory uptake, whereby plants respond to non-uniform, limiting conditions by increasing water uptake from areas in the root zone characterized by more favorable conditions, is one such mechanism by which plants sustain potential transpiration rates in drying soils. The development of models which accurately characterize temporal and spatial root water uptake patterns is important for agricultural resource optimization, upon which subsequent management decisions affecting resource conservation and environmental pollution are based. Numerical simulations of root water

  10. Assessing irrigated agriculture's surface water and groundwater consumption by combining satellite remote sensing and hydrologic modelling.

    PubMed

    Peña-Arancibia, Jorge L; Mainuddin, Mohammed; Kirby, John M; Chiew, Francis H S; McVicar, Tim R; Vaze, Jai

    2016-01-15

    Globally, irrigation accounts for more than two thirds of freshwater demand. Recent regional and global assessments indicate that groundwater extraction (GWE) for irrigation has increased more rapidly than surface water extraction (SWE), potentially resulting in groundwater depletion. Irrigated agriculture in semi-arid and arid regions is usually from a combination of stored surface water and groundwater. This paper assesses the usefulness of remotely-sensed (RS) derived information on both irrigation dynamics and rates of actual evapotranspiration which are both input to a river-reach water balance model in order to quantify irrigation water use and water provenance (either surface water or groundwater). The assessment is implemented for the water-years 2004/05-2010/11 in five reaches of the Murray-Darling Basin (Australia); a heavily regulated basin with large irrigated areas and periodic droughts and floods. Irrigated area and water use are identified each water-year (from July to June) through a Random Forest model which uses RS vegetation phenology and actual evapotranspiration as predicting variables. Both irrigated areas and actual evapotranspiration from irrigated areas were compared against published estimates of irrigated areas and total water extraction (SWE+GWE).The river-reach model determines the irrigated area that can be serviced with stored surface water (SWE), and the remainder area (as determined by the Random Forest Model) is assumed to be supplemented by groundwater (GWE). Model results were evaluated against observed SWE and GWE. The modelled SWE generally captures the observed interannual patterns and to some extent the magnitudes, with Pearson's correlation coefficients >0.8 and normalised root-mean-square-error<30%. In terms of magnitude, the results were as accurate as or better than those of more traditional (i.e., using areas that fluctuate based on water resource availability and prescribed crop factors) irrigation modelling. The RS

  11. Evaluation of Monensin Transport to Shallow Groundwater after Irrigation with Dairy Lagoon Water.

    PubMed

    Hafner, Sarah C; Harter, Thomas; Parikh, Sanjai J

    2016-03-01

    Animal waste products from concentrated animal feeding operations are a significant source of antibiotics to the environment. Monensin, an ionophore antibiotic commonly used to increase feed efficiency in livestock, is known to have varied toxicological effects on nontarget species. The current study builds on prior studies evaluating the impact of dairy management on groundwater quality by examining the transport of monensin in an agricultural field with coarse-textured soils during irrigation with lagoon wastewater. The dairy is located in California's San Joaquin Valley, where groundwater can be encountered <5 m below the surface. Groundwater samples were collected from a network of monitoring wells installed throughout the dairy and adjacent to irrigated fields before and after an irrigation event, which allowed for measurement of monensin potentially reaching the shallow groundwater as a direct result of irrigation with lagoon water. Monensin was extracted from water samples via hydrophilic-lipophilic balance solid-phase extraction and quantified with liquid chromatography-mass spectrometry. Irrigation water was found to contain up to 1.6 μg L monensin, but monensin was only detected in monitoring wells surrounding the waste storage lagoon. Water chemistry changes in the wells bordering the irrigated field suggest that up to 7% of irrigation water reached groundwater within days of irrigation. The study suggests that contamination of groundwater with monensin can occur primarily by compromised waste storage systems and that rapid transport of monensin to groundwater is not likely to occur from a single irrigation event. PMID:27065394

  12. Compensating inherent linear move water application errors using a variable rate irrigation system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Continuous move irrigation systems such as linear move and center pivot irrigate unevenly when applying conventional uniform water rates due to the towers/motors stop/advance pattern. The effect of the cart movement pattern on linear move water application is larger on the first two spans which intr...

  13. Improving estimates of N and P loads in irrigation water from swine manure lagoons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The implementation of nutrient management plans (NMPs) for confined animal feeding operations (CAFOs) requires recording N and P loads from land-applied manure, including nutrients applied in irrigation water from manure treatment lagoons. By regulation, lagoon irrigation water nutrient records in ...

  14. Improving N and P estimates for swine manure lagoon irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient management plans (NMPs) for confined animal feeding operations (CAFOs) require a record of N and P loads from manure land-applications, including irrigation with lagoon water. Mississippi regulations require nutrient records for lagoon irrigation water be based on at least one annual analy...

  15. Adapting irrigation management to water scarcity: constraints of plant growth, hydraulics and carbon assimilation.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water shortages are responsible for the greatest crop losses around the world and are expected to worsen. In arid areas where agriculture is dependent on irrigation, various forms of deficit irrigation management have been suggested to optimize crop yields for available soil water. The relationshi...

  16. Irrigation water is an unlikely source of inoculum of Pseudomonas cannabina pv. alisalensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas cannabina pv. alisalensis causes severe bacterial blight on crucifers across the United States. These experiments examined the potential of irrigation water as a source of inoculum for P. cannabina pv. alisalensis. Water samples were collected from multiple irrigation reservoirs and spri...

  17. Perchlorate uptake in spinach as related to perchlorate, nitrate and chloride concentrations in irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several studies have reported on the detection of perchlorate in edible leafy vegetables irrigated with Colorado River water. However, there is no information on spinach as related to perchlorate in irrigation water nor on the effect of other anions on perchlorate uptake. A greenhouse perchlorate up...

  18. Simulated Corn Yield Responses to Limited-Water Irrigation Under Varying Soil and Climate Conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water holding capacity of soils is a key factor in successful dryland and irrigated agriculture as it influences the fraction of precipitation and irrigation that is stored in the soil profile that can be subsequently used for crop production. There is a well-known dependence of water holding capaci...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  20. Optimal demand reponse to water pricing policies under limited water supply in irrigation: a case study

    NASA Astrophysics Data System (ADS)

    Grießbach, Ulkrike; Stange, Peter; Schuetze, Niels

    2015-04-01

    Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with the higher demand of water, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand. For modeling the regional water demand, local stochastic water demand functions are used which are derived from optimized agronomic response on farms scale. These functions take into account different soil types, crops, stochastically generated climate scenarios considering different economic conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed and applied for a case study in Saxony which helps to evaluate combined water supply and demand management policies on a regional level.

  1. Assessment of water use in the Spanish irrigation district "Río Adaja"

    NASA Astrophysics Data System (ADS)

    Naroua, Illiassou; Rodriguez-Sinobas, Leonor; Sánchez Calvo, Raúl

    2013-04-01

    Intensive agricultural practices combined with the increasing pressure of urbanization and the changing lifestyles, have strengthened the problems of competing users over limited water resources in a fragile and already stressed environment. Sustainable irrigated agriculture is prescribed as a policy approach that maximizes economic benefits while maintaining environmental quality. Within this framework a proper management of irrigation systems saving water is required. On the other hand, crops with high tolerance to water stress and deficit irrigation are recommended. However, crop yield, among other factors, is very sensitive to water Thus, studies addressing the relations among crop water requirements, irrigation depth and crop yield are necessary. This type of study has been carried out in the Spanish irrigation District "Río Adaja" in the year 2010-2011 with the crops: wheat, barley, sugarbeet, corn, onion, potato, sunflower, clover and carrot. A soil hydrology balance model was applied taking into account climatic data for the nearby weather station and soil characteristics. Effective precipitation was calculated by the index curve number. Crop water requirements were calculated by the FAO Penman-Monteith with the application of the dual crop coefficient. Likewise, productivity was measured by the following indexes: annual relative irrigation supply (ARIS), relative water supply (RWS), relative rainfall supply (RS) and water productivity (WP). Results show that water applied with the irrigation of clover, sugarbeet, corn and onion was less than their water requirements There was a 35 % difference between the amount of water simulated with the model and the gross amount applied during the irrigation period by the irrigation district. WP values differed among crops depending, mainly, on the crop`s market price and the amount of irrigation water. The highest values corresponded to potato and onion crops.

  2. A coupled agronomic-economic model to consider allocation of brackish irrigation water

    NASA Astrophysics Data System (ADS)

    Ben-Gal, Alon; Weikard, Hans-Peter; Shah, Syed Hamid Hussain; Zee, Sjoerd E. A. T. M.

    2013-05-01

    In arid and semiarid regions, irrigation water is scarce and often contains high concentrations of salts. To reduce negative effects on crop yields, the irrigated amounts must include water for leaching and therefore exceed evapotranspiration. The leachate (drainage) water returns to water sources such as rivers or groundwater aquifers and increases their level of salinity and the leaching requirement for irrigation water of any sequential user. We develop a conceptual sequential (upstream-downstream) model of irrigation that predicts crop yields and water consumption and tracks the water flow and level of salinity along a river dependent on irrigation management decisions. The model incorporates an agro-physical model of plant response to environmental conditions including feedbacks. For a system with limited water resources, the model examines the impacts of water scarcity, salinity and technically inefficient application on yields for specific crop, soil, and climate conditions. Moving beyond the formulation of a conceptual frame, we apply the model to the irrigation of Capsicum annum on Arava Sandy Loam soil. We show for this case how water application could be distributed between upstream and downstream plots or farms. We identify those situations where it is beneficial to trade water from upstream to downstream farms (assuming that the upstream farm holds the water rights). We find that water trade will improve efficiency except when loss levels are low. We compute the marginal value of water, i.e., the price water would command on a market, for different levels of water scarcity, salinity and levels of water loss.

  3. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Can I receive irrigation water if I am granted an Annual... AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an Annual Assessment Waiver? No. Water will not be delivered in any...

  4. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Can I receive irrigation water if I am granted an Annual... AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an Annual Assessment Waiver? No. Water will not be delivered in any...

  5. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Can I receive irrigation water if I am granted an Annual... AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an Annual Assessment Waiver? No. Water will not be delivered in any...

  6. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Can I receive irrigation water if I am granted an Annual... AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an Annual Assessment Waiver? No. Water will not be delivered in any...

  7. GlobWat - a global water balance model to assess water use in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Hoogeveen, J.; Faurès, J.-M.; Peiser, L.; Burke, J.; van de Giesen, N.

    2015-01-01

    GlobWat is a freely distributed, global soil water balance model that is used by FAO to assess water use in irrigated agriculture; the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high resolution datasets that are consistent at global level and calibrated against values for Internal Renewable Water Resources, as published in AQUASTAT, FAO's global information system on water and agriculture. Validation of the model is done against mean annual river basin outflows. The water balance is calculated in two steps: first a "vertical" water balance is calculated that includes evaporation from in situ rainfall ("green" water) and incremental evaporation from irrigated crops. In a second stage, a "horizontal" water balance is calculated to determine discharges from river (sub-)basins, taking into account incremental evaporation from irrigation, open water and wetlands ("blue" water). The paper describes methodology, input and output data, calibration and validation of the model. The model results are finally compared with other global water balance models.

  8. GlobWat - a global water balance model to assess water use in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Hoogeveen, J.; Faurès, J.-M.; Peiser, L.; Burke, J.; van de Giesen, N.

    2015-09-01

    GlobWat is a freely distributed, global soil water balance model that is used by the Food and Agriculture Organization (FAO) to assess water use in irrigated agriculture, the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high-resolution data sets that are consistent at global level and calibrated against values for internal renewable water resources, as published in AQUASTAT, the FAO's global information system on water and agriculture. Validation of the model is done against mean annual river basin outflows. The water balance is calculated in two steps: first a "vertical" water balance is calculated that includes evaporation from in situ rainfall ("green" water) and incremental evaporation from irrigated crops. In a second stage, a "horizontal" water balance is calculated to determine discharges from river (sub-)basins, taking into account incremental evaporation from irrigation, open water and wetlands ("blue" water). The paper describes the methodology, input and output data, calibration and validation of the model. The model results are finally compared with other global water balance models to assess levels of accuracy and validity.

  9. Market Simulations for Irrigation Water Rights: A Hypothetical Case Study

    NASA Astrophysics Data System (ADS)

    Wong, Benedict D. C.; Eheart, J. Wayland

    1983-10-01

    The efficiency of two marketable water rights systems in a lentic (lakelike) structure is assessed quantitatively for a case study based on hypothetical irrigation water use. Water rights are simulated on the bases of (1) the expected values of water rights to the users and (2) perfect foresight on the parts of users, and the economic outcomes of these markets are evaluated from both ex ante and ex post perspectives. The market outcomes are compared to the optimal (efficient) scheme and to two alternative nonmarket policies. Distributional aspects of the markets are examined on the basis of individual payoff. Simulation results show that higher efficiency is obtained for the two market systems than for the nonmarket policies and that the market systems recoup about 95% of the economic value of the optimal distribution. The results suggest that most of the 5% efficiency loss should be attributed to the design of the market system itself (i.e., the restrictions imposed by the definition of the rights and/or the water rights allocation policy), rather than the users' inability to predict future events.

  10. Breeding Horticultural Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant breeding involves selection of plants with combinations of improved traits that are inherited in a predictable manner. Collecting, understanding, and incorporating genetic variation into a horticultural breeding program are critical to success. Clearly defined goals help plant breeders choose ...

  11. Agricultural-to-hydropower water transfers: sharing water and benefits in hydropower-irrigation systems

    NASA Astrophysics Data System (ADS)

    Tilmant, A.; Goor, Q.; Pinte, D.

    2009-07-01

    This paper presents a methodology to assess agricultural-to-hydropower water transfers in water resources systems where irrigation crop production and hydropower generation are the main economic activities. In many countries, water for crop irrigation is often considered as a static asset: irrigation water is usually allocated by a system of limited annual rights to use a prescribed volume of water, which remains to a large extent independent of the availability of water in the basin. The opportunity cost (forgone benefits) of this static management approach may be important in river basins where large irrigation areas are present in the upstream reaches. Continuously adjusting allocation decisions based on the hydrologic status of the system will lead to the temporary reallocation of some (or all) of the irrigation water downstream to consumptive and/or non-consumptive users. Such a dynamic allocation process will increase the social benefits if the sum of the downstream productivities exceeds those of the upstream farmers whose entitlements are curtailed. However, this process will be socially acceptable if upstream farmers are compensated for increasing the availability of water downstream. This paper also presents a methodology to derive the individual contribution of downstream non-consumptive users, i.e. hydropower plants, to the financial compensation of upstream farmers. This dynamic management approach is illustrated with a cascade of multipurpose reservoirs in the Euphrates river basin. The analysis of simulation results reveals that, on average, the annual benefits obtained with the dynamic allocation process are 6% higher that those derived from a static allocation.

  12. On farm evaluation of the effect of low cost drip irrigation on water and crop productivity compared to conventional surface irrigation system

    NASA Astrophysics Data System (ADS)

    Maisiri, N.; Senzanje, A.; Rockstrom, J.; Twomlow, S. J.

    This on-farm research study was carried out at Zholube irrigation scheme in a semi-arid agro tropical climate of Zimbabwe to determine how low cost drip irrigation technologies compare with conventional surface irrigation systems in terms of water and crop productivity. A total of nine farmers who were practicing surface irrigation were chosen to participate in the study. The vegetable English giant rape ( Brassica napus) was grown under the two irrigation systems with three fertilizer treatments in each system: ordinary granular fertilizer, liquid fertilizer (fertigation) and the last treatment with no fertilizer. These trials were replicated three times in a randomized block design. Biometric parameters of leaf area index (LAI) and fresh weight of the produce, water use efficiency (WUE) were used to compare the performance of the two irrigation systems. A water balance of the inflows and outflows was kept for analysis of WUE. The economic profitability and the operation, maintenance and management requirements of the different systems were also evaluated. There was no significant difference in vegetable yield between the irrigation systems at 8.5 ton/ha for drip compared to 7.8 ton/ha in surface irrigation. There were significant increases in yields due to use of fertilizers. Drip irrigation used about 35% of the water used by the surface irrigation systems thus giving much higher water use efficiencies. The leaf area indices were comparable in both systems with the same fertilizer treatment ranging between 0.05 for surface without fertilizer to 6.8 for low cost drip with fertigation. Low cost drip systems did not reflect any labour saving especially when manually lifting the water into the drum compared to the use of siphons in surface irrigation systems. The gross margin level for surface irrigation was lower than for low cost drip irrigation but the gross margin to total variable cost ratio was higher in surface irrigation systems, which meant that surface

  13. Potentials and problems of sustainable irrigation with water high in salts

    NASA Astrophysics Data System (ADS)

    Ben-Gal, Alon

    2015-04-01

    Water scarcity and need to expand agricultural productivity have led to ever growing utilization of poor quality water for irrigation of crops. Almost in all cases, marginal or alternative water sources for irrigation contain relatively high concentrations of dissolved salts. When salts are present, irrigation water management, especially in the dry regions where water requirements are highest, must consider leaching in addition to crop evapotranspiration requirements. Leaching requirements for agronomic success are calculable and functions of climate, soil, and very critically, of crop sensitivity and the actual salinity of the irrigation water. The more sensitive the crop and more saline the water, the higher the agronomic cost and the greater the quantitative need for leaching. Israel is a forerunner in large-scale utilization of poor quality water for irrigation and can be used as a case study looking at long term repercussions of policy alternatively encouraging irrigation with recycled water or brackish groundwater. In cases studied in desert conditions of Israel, as much of half of the water applied to crops including bell peppers in greenhouses and date palms is actually used to leach salts from the root zone. The excess water used to leach salts and maintain agronomic and economic success when irrigating with water containing salts can become an environmental hazard, especially in dry areas where natural drainage is non-existent. The leachate often contains not only salts but also agrochemicals including nutrients, and natural contaminants can be picked up and transported as well. This leachate passes beyond the root zone and eventually reaches ground or surface water resources. This, together with evidence of ongoing increases in sodium content of fresh produce and increased SAR levels of soils, suggest that the current policy and practice in Israel of utilization of high amounts of low quality irrigation water is inherently non- sustainable. Current

  14. Assessment of water use and its productivity in the Spanish irrigation district "Río Adaja"

    NASA Astrophysics Data System (ADS)

    Rodriguez-Sinobas, Leonor; Naroua, Iliassou; Sánchez-Calvo, Raúl

    2015-04-01

    A study of the assessment of the irrigation water use has been carried out in the Spanish irrigation District "Río Adaja" that has analyzed the water use efficiency and the water productivity indicators for the main crops during the first three years of operation (2010/2011, 2011/2012 and 2012/2013). A soil water balance model was applied taking into account climatic data for the nearby weather station and soil properties. Crop water requirements were calculated by the FAO Penman-Monteith with the application of the dual crop coefficient and by considering the readily available soil water content (RAW) concept. Likewise, productivity was measured by the indexes: annual relative irrigation supply (ARIS), annual relative water supply (ARWS), relative rainfall supply (RRS), the water productivity (WP), the evapotranspiration water productivity (ETWP), and the irrigation water productivity (IWP). The results show that the irrigation district applied deficit irrigation in most crops (ARIS<1), and also improved water productivity. This was higher in 2010/2011 which showed the highest effective precipitation Pe. The IWP (€/m3) index varied among crops with the highest values for onion (4.14), potato (2.79), carrot (1.37) and barley (1.21) for the first year and, onion (1.98), potato (1.69), carrot (1.70) and barley (1.16) in the second year. Thus, these crops would be a proper cropping pattern to maximize the gross income in the irrigation district.

  15. Assessing soil water storage distribution under sprinkler irrigation by coupling 3D simulations and field observations

    NASA Astrophysics Data System (ADS)

    Taha, Uday; Shabeeb, Ahmed; dragonetti, giovanna; Lamaddalena, Nicola; Coppola, Antonio

    2016-04-01

    This work analyzed the variability of sprinkler irrigation application over a bare soil, both in terms of water application efficiency and uniformity, by integrating and comparing the information on the irrigation depth data (ID), as measured by catch cans, soil water storage in the upper root zone, as measured by TDR probes, and a 3D simulations of water flow in soils. Three irrigation tests were performed at three different pressures (2, 3 and 4 bar). A lateral water redistribution was observed and simulated after each irrigation event by comparing spatial distributions of site-specific water application efficiency (AEs), as well as ratios of site-specific actual water storage increase (SWEs) and irrigation depth (IDs) to the water content before irrigation. Because of soil water redistribution processes, distribution uniformity based on soil storages was systematically higher than the catch can uniformity. The obvious consequence of lateral water redistribution processes was that the soil smoothing action on non-uniformity observed at the surface increased both with depth and over time. At a given depth the uniformity of soil water storages always attained the same value, whatever the pressure considered and the catch can-based uniformity coefficient. It was concluded that, for the case of random distribution of ID, the uniformity of water storages is driven by the soil behavior rather than by the irrigation system.

  16. Farm water budgets for semiarid irrigated floodplains of northern New Mexico: characterizing the surface water-groundwater interactions

    NASA Astrophysics Data System (ADS)

    Gutierrez, K. Y.; Fernald, A.; Ochoa, C. G.; Guldan, S. J.

    2013-12-01

    KEY WORDS - Hydrology, Water budget, Deep percolation, Surface water-Groundwater interactions. With the recent projections for water scarcity, water balances have become an indispensable water management tool. In irrigated floodplains, deep percolation from irrigation can represent one of the main aquifer recharge sources. A better understanding of surface water and groundwater interactions in irrigated valleys is needed for properly assessing the water balances in these systems and estimating potential aquifer recharge. We conducted a study to quantify the parameters and calculate the water budgets in three flood irrigated hay fields with relatively low, intermediate and, high water availability in northern New Mexico. We monitored different hydrologic parameters including total amount of water applied, change in soil moisture, drainage below the effective root zone, and shallow water level fluctuations in response to irrigation. Evapotranspiration was calculated from weather station data collected in-situ using the Samani-Hargreaves. Previous studies in the region have estimated deep percolation as a residual parameter of the water balance equation. In this study, we used both, the water balance method and actual measurements of deep percolation using passive lysimeters. Preliminary analyses for the three fields show a relatively rapid movement of water through the upper 50 cm of the vadose zone and a quick response of the shallow aquifer under flood irrigation. Further results from this study will provide a better understanding of surface water-groundwater interactions in flood irrigated valleys in northern New Mexico.

  17. Evaluating the accuracy of soil water sensors for irrigation scheduling to conserve freshwater

    NASA Astrophysics Data System (ADS)

    Ganjegunte, Girisha K.; Sheng, Zhuping; Clark, John A.

    2012-06-01

    In the Trans-Pecos area, pecan [ Carya illinoinensis (Wangenh) C. Koch] is a major irrigated cash crop. Pecan trees require large amounts of water for their growth and flood (border) irrigation is the most common method of irrigation. Pecan crop is often over irrigated using traditional method of irrigation scheduling by counting number of calendar days since the previous irrigation. Studies in other pecan growing areas have shown that the water use efficiency can be improved significantly and precious freshwater can be saved by scheduling irrigation based on soil moisture conditions. This study evaluated the accuracy of three recent low cost soil water sensors (ECH2O-5TE, Watermark 200SS and Tensiometer model R) to monitor volumetric soil water content (θv) to develop improved irrigation scheduling in a mature pecan orchard in El Paso, Texas. Results indicated that while all three sensors were successful in following the general trends of soil moisture conditions during the growing season, actual measurements differed significantly. Statistical analyses of results indicated that Tensiometer provided relatively accurate soil moisture data than ECH2O-5TE and Watermark without site-specific calibration. While ECH2O-5TE overestimated the soil water content, Watermark and Tensiometer underestimated. Results of this study suggested poor accuracy of all three sensors if factory calibration and reported soil water retention curve for study site soil texture were used. This indicated that sensors needed site-specific calibration to improve their accuracy in estimating soil water content data.

  18. [Simulation of soil water dynamics in triploid Populus tomentosa root zone under subsurface drip irrigation].

    PubMed

    Xi, Ben-Ye; Jia, Li-Ming; Wang, Ye; Li, Guang-De

    2011-01-01

    Based on the observed data of triploid Populus tomentosa root distribution, a one-dimensional root water uptake model was proposed. Taking the root water uptake into account, the soil water dynamics in triploid P. tomentosa root zone under subsurface drip irrigation was simulated by using HYDRUS model, and the results were validated with field experiment. Besides, the HYDRUS model was used to study the effects of various irrigation technique parameters on soil wetting patterns. The RMAE for the simulated soil water content by the end of irrigation and approximately 24 h later was 7.8% and 6.0%, and the RMSE was 0.036 and 0.026 cm3 x cm(-3), respectively, illustrating that the HYDRUS model performed well in simulating the short-term soil water dynamics in triploid P. tomentosa root zone under drip irrigation, and the root water uptake model was reasonable. Comparing with 2 and 4 L x h(-1) of drip discharge and continuous irrigation, both the 1 L x h(-1) of drip discharge and the pulsed irrigation with water applied intermittently in 30 min periods could increase the volume of wetted soil and reduce deep percolation. It was concluded that the combination of 1 L x h(-1) of drip discharge and pulsed irrigation should be the first choice when applying drip irrigation to triploid P. tomentosa root zone at the experiment site. PMID:21548283

  19. Irrigation depth far exceeds water uptake depth in an oasis cropland in the middle reaches of Heihe River Basin

    PubMed Central

    Yang, Bin; Wen, Xuefa; Sun, Xiaomin

    2015-01-01

    Agricultural irrigation in the middle reaches of the Heihe River Basin consumes approximately 80% of the total river water. Whether the irrigation depth matches the water uptake depth of crops is one of the most important factors affecting the efficiency of irrigation water use. Our results indicated that the influence of plastic film on soil water δ18O was restricted to 0–30 cm soil depth. Based on a Bayesian model (MixSIR), we found that irrigated maize acquired water preferentially from 0–10 cm soil layer, with a median uptake proportion of 87 ± 15%. Additionally, maize utilised a mixture of irrigation and shallow soil water instead of absorbing the irrigation water directly. However, only 24.7 ± 5.5% of irrigation water remained in 0–10 cm soil layer, whereas 29.5 ± 2.8% and 38.4 ± 3.3% of the irrigation water infiltrated into 10–40 cm and 40–80 cm layers. During the 4 irrigation events, approximately 39% of the irrigation and rainwater infiltrated into soil layers below 80 cm. Reducing irrigation amount and developing water-saving irrigation methods will be important strategies for improving the efficiency of irrigation water use in this area. PMID:26463010

  20. Irrigation depth far exceeds water uptake depth in an oasis cropland in the middle reaches of Heihe River Basin.

    PubMed

    Yang, Bin; Wen, Xuefa; Sun, Xiaomin

    2015-01-01

    Agricultural irrigation in the middle reaches of the Heihe River Basin consumes approximately 80% of the total river water. Whether the irrigation depth matches the water uptake depth of crops is one of the most important factors affecting the efficiency of irrigation water use. Our results indicated that the influence of plastic film on soil water δ(18)O was restricted to 0-30 cm soil depth. Based on a Bayesian model (MixSIR), we found that irrigated maize acquired water preferentially from 0-10 cm soil layer, with a median uptake proportion of 87 ± 15%. Additionally, maize utilised a mixture of irrigation and shallow soil water instead of absorbing the irrigation water directly. However, only 24.7 ± 5.5% of irrigation water remained in 0-10 cm soil layer, whereas 29.5 ± 2.8% and 38.4 ± 3.3% of the irrigation water infiltrated into 10-40 cm and 40-80 cm layers. During the 4 irrigation events, approximately 39% of the irrigation and rainwater infiltrated into soil layers below 80 cm. Reducing irrigation amount and developing water-saving irrigation methods will be important strategies for improving the efficiency of irrigation water use in this area. PMID:26463010

  1. Irrigation depth far exceeds water uptake depth in an oasis cropland in the middle reaches of Heihe River Basin

    NASA Astrophysics Data System (ADS)

    Yang, Bin; Wen, Xuefa; Sun, Xiaomin

    2015-10-01

    Agricultural irrigation in the middle reaches of the Heihe River Basin consumes approximately 80% of the total river water. Whether the irrigation depth matches the water uptake depth of crops is one of the most important factors affecting the efficiency of irrigation water use. Our results indicated that the influence of plastic film on soil water δ18O was restricted to 0-30 cm soil depth. Based on a Bayesian model (MixSIR), we found that irrigated maize acquired water preferentially from 0-10 cm soil layer, with a median uptake proportion of 87 ± 15%. Additionally, maize utilised a mixture of irrigation and shallow soil water instead of absorbing the irrigation water directly. However, only 24.7 ± 5.5% of irrigation water remained in 0-10 cm soil layer, whereas 29.5 ± 2.8% and 38.4 ± 3.3% of the irrigation water infiltrated into 10-40 cm and 40-80 cm layers. During the 4 irrigation events, approximately 39% of the irrigation and rainwater infiltrated into soil layers below 80 cm. Reducing irrigation amount and developing water-saving irrigation methods will be important strategies for improving the efficiency of irrigation water use in this area.

  2. An assessment of global net irrigation water requirements from various water supply sources to sustain irrigation: rivers and reservoirs (1960-2050)

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Cho, J.; Yamada, H. G.; Hanasaki, N.; Kanae, S.

    2014-10-01

    Water supply sources for irrigation (e.g. rivers and reservoirs) are critically important for agricultural productivity. The current rapid increase in irrigation water use is considered unsustainable and threatens food production. In this study, we estimated the time-varying dependence of irrigation water requirements from water supply sources, with a particular focus on variations in irrigation area during past (1960-2001) and future (2002-2050) periods using the global water resources model, H08. The H08 model can simulate water requirements on a daily basis at a resolution of 1.0° × 1.0° latitude and longitude. The sources of irrigation water requirements in the past simulations were specified using four categories: rivers (RIV), large reservoirs (LR) with a storage capacity greater than 1.0 × 109 m3, medium-size reservoirs (MSR) with storage capacities ranging from 1.0 × 109 m3 to 3.0 × 106 m3, and non-local non-renewable blue water (NNBW). The simulated results from 1960 to 2001 showed that RIV, MSR and NNBW increased significantly from the 1960s to the early 1990s globally, but LR increased at a relatively low rate. After the early 1990s, the increase in RIV declined as it approached a critical limit, due to the continued expansion of irrigation area. MSR and NNBW increased significantly, during the same time period, following the expansion of the irrigation area and the increased storage capacity of the medium-size reservoirs. We also estimated future irrigation water requirements from the above four water supply sources and an additional water supply source (ADD) in three future simulation designs; irrigation area change, climate change, and changes in both irrigation area and climate. ADD was defined as a future increase in NNBW. After the 2020s, MSR was predicted to approach the critical limit, and ADD would account for 11-23% of the total requirements in the 2040s.

  3. Water and solute balances as a basis for sustainable irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Pla-Sentís, Ildefonso

    2015-04-01

    The growing development of irrigated agriculture is necessary for the sustainable production of the food required by the increasing World's population. Such development is limited by the increasing scarcity and low quality of the available water resources and by the competitive use of the water for other purposes. There are also increasing problems of contamination of surface and ground waters to be used for other purposes by the drainage effluents of irrigated lands. Irrigation and drainage may cause drastic changes in the regime and balance of water and solutes (salts, sodium, contaminants) in the soil profile, resulting in problems of water supply to crops and problems of salinization, sodification and contamination of soils and ground waters. This is affected by climate, crops, soils, ground water depth, irrigation and groundwater composition, and by irrigation and drainage management. In order to predict and prevent such problems for a sustainable irrigated agriculture and increased efficiency in water use, under each particular set of conditions, there have to be considered both the hydrological, physical and chemical processes determining such water and solute balances in the soil profile. In this contribution there are proposed the new versions of two modeling approaches (SOMORE and SALSODIMAR) to predict those balances and to guide irrigation water use and management, integrating the different factors involved in such processes. Examples of their application under Mediterranean and tropical climate conditions are also presented.

  4. Irrigation efficiency and water-policy implications for river basin resilience

    NASA Astrophysics Data System (ADS)

    Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

    2014-04-01

    Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface water and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly considers three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

  5. Probabilistic description of crop development and irrigation water requirements with stochastic rainfall

    NASA Astrophysics Data System (ADS)

    Vico, Giulia; Porporato, Amilcare

    2013-03-01

    Supplemental irrigation represents one of the main strategies to mitigate the effects of climatic variability on agroecosystems, stabilizing yields and profits. Because of the significant investments and water requirements associated with irrigation, strategic choices are needed to preserve productivity and profitability while ensuring a sustainable water management, a nontrivial task given rainfall unpredictability. Decision-making under uncertainty requires the knowledge of the probability density function (pdf) of the outcome variable (yield and economic return) for the different management alternatives to be considered (here, irrigation strategies). A stochastic framework is proposed, linking probabilistically the occurrence of rainfall events and irrigation applications to crop development during the growing season. Based on these linkages, the pdf of yields and the corresponding irrigation requirements are obtained analytically as a function of climate, soil, and crop parameters, for different irrigation strategies and both unlimited and limited water availability. Approximate expressions are also presented to facilitate their application. Our results employ relatively few parameters and are thus broadly applicable to different crops and sites, under current- and future-climate scenarios, offering a quantitative tool to quantify the impact of irrigation strategies and water allocation on yields. As a tool for decision-making under uncertainty (e.g., via expected utility theory), our framework will be useful for the assessment of the feasibility of different irrigation strategies and water allocations, toward a sustainable management of water resources for human and environmental needs.

  6. Reclamation of used urban waters for irrigation purposes--a review of treatment technologies.

    PubMed

    Norton-Brandão, Diana; Scherrenberg, Sigrid M; van Lier, Jules B

    2013-06-15

    The worldwide fresh water scarcity is increasing the demand for non-conventional water resources. Despite the technology being available for application of treated wastewater in irrigation, the use of effluent in agriculture is not being properly managed in the majority of cases. Industrial countries, where financial resources are available but restricted, face difficulties in some cases related to the lack of a complete definition of irrigation water quality standards, as well as to the lack of monitoring components that determine if the effluent is suitable for such use. The present paper presents a critical review on urban reclamation technologies for irrigation. The technologies are presented by the four most important parameters for irrigation water quality: salinity, pathogens, nutrients and heavy metals. An overview is given of the current, on-going evaluation of different reclamation technologies for irrigation. PMID:23562951

  7. Soil chemical changes resulting from irrigation with water co-produced with coalbed natural gas

    SciTech Connect

    Ganjegunte, G.K.; Vance, G.F.; King, L.A.

    2005-12-01

    Land application of coalbed natural gas (CBNG) co-produced water is a popular management option within northwestern Powder River Basin (PRB) of Wyoming. This study evaluated the impacts of land application of CBNG waters on soil chemical properties at five sites. Soil samples were collected from different depths (0-5, 5-15, 15-30, 30-60, 60-90, and 90-120 cm) from sites that were irrigated with CBNG water for 2 to 3 yr and control sites. Chemical properties of CBNG water used for irrigation on the study sites indicate that electrical conductivity of CBNG water (EC{sub w}) and sodium adsorption ratio of CBNG water (SAR{sub w}) values were greater than those recommended for irrigation use on the soils at the study sites. Soil chemical analyses indicated that electrical conductivity of soil saturated paste extracts (ECe) and sodium adsorption ratio of soil saturated paste extracts (SAR(e)) values for irrigated sites were significantly greater (P < 0.05) than control plots in the upper 30-cm soil depths. Mass balance calculations suggested that there has been significant buildup of Na in irrigated soils due to CBNG irrigation water as well as Na mobilization within the soil profiles. Results indicate that irrigation with CBNG water significantly impacts certain soil properties, particularly if amendments are not properly utilized. This study provides information for better understanding changes in soil properties due to land application of CBNG water.

  8. Irrigation efficiency and water-policy implications for river-basin resilience

    NASA Astrophysics Data System (ADS)

    Scott, C. A.; Vicuña, S.; Blanco-Gutiérrez, I.; Meza, F.; Varela-Ortega, C.

    2013-07-01

    Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface- and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river-basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly examines policy frameworks in three regional contexts with broadly similar climatic and water-resource conditions - central Chile, southwestern US, and south-central Spain - where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

  9. Productivity of irrigated bean submitted to water deficit in different phenological stages

    NASA Astrophysics Data System (ADS)

    Miorini, T. J. J.; Saad, J. C. C.

    2012-04-01

    Water scarcity is the most important factor limiting crop yields worldwide. An increased sustainable use of irrigation water will be necessary to feed our growing population. Bean (Phaseolus vulgaris L.) is widespread in the social and economic scene in Brazil, as well it is Brazilian population main dish, and it also helps small and medium farmers' income. The damage caused by water deficit depends on the duration, severity and stage of plant development. The bean plant is classified as sensitive to both water deficit and excess water in the soil. The hypothesis is that if the water supply is suppressed in just one of the five development stages of irrigated beans, it can result in productivity reduction lower than 20%, allowing water economy. The objective of this study was to compare the performance of bean Carioca group IAC Alvorada yield components, with irrigation suppression in each of the five phenological phases (emergence, vegetative, flowering, grain filling and maturation) and no irrigation and irrigated in all stages. The study was conducted at Agronomical Sciences College, UNESP, Botucatu, SP, Brazil. The statistical design was the randomized block with seven treatments and four replications. Data were subjected to analysis of variance and "t" test at 5% probability. The irrigation suppression only during emergence, filling, and maturation phases did not show any statistical difference in productivity when compared with the irrigated at all stages. The irrigation suppression at vegetative and flowering phase, reduced the production at 75.1 and 76.2%, respectively, when compared with irrigation at all stages, despite the reduction of the water depth being around 20% for flowering and 33.8% for the vegetative phase when compared to the irrigated at all stages. Irrigation suppression in all phases generated a reduction of approximately 87.3% when compared with irrigation at all stages. During the experiment there was a total recorded rainfall of 156mm

  10. Water relations of differentially irrigated cotton exposed to ozone

    SciTech Connect

    Temple, P.J.

    1990-01-01

    The field study was conducted to test the hypothesis that plants chronically exposed to O{sub 3} may be more susceptible to drought because O{sub 3} typically inhibits root growth and increases shoot-root ratios in plants. Cotton was grown in open-top chambers on Hanford coarse sandy loam in Riverside, CA. Plants were grown under three irrigation regimes: Optimum water for lint production (OW), suboptimum or moderate drought stress (SO), and severely drought stressed (SS) and were exposed to seasonal 12 h (0800-2000) O{sub 3} centrations of 0.015, 0.074, 0.094, or 0.111/microLL. Leaf xylem pressure potentials Psi(sub 1) and soil water content Theta(sub v) were measured weekly from June to October. Mean seasonal Psi(sub 1) increased from -1.89 MPa to -1.72 MPa in low to high O{sub 3} treatments, averaged across soil water regimes. Ozone had no effect on seasonal water use of cotton, but water use efficiency was significantly reduced by O{sub 3} in OW and SO, but not in SS treatments. Drought-stressed plants extracted proportionally greater amounts of water from deeper in the soil profile than OW cotton, and O{sub 3} had no apparent effect on this redistribution of roots in the soil. Since O{sub 3} had no apparent effect on the ability of drought-stressed cotton to maintain Psi(sub 1) and to increase root growth relative to shoot growth, this suggests that O{sub 3} may have little or no effect on the potential of cotton to adapt to or tolerate drought.

  11. Gender and power contestations over water use in irrigation schemes: Lessons from the lake Chilwa basin

    NASA Astrophysics Data System (ADS)

    Nkhoma, Bryson; Kayira, Gift

    2016-04-01

    Over the past two decades, Malawi has been adversely hit by climatic variability and changes, and irrigation schemes which rely mostly on water from rivers have been negatively affected. In the face of dwindling quantities of water, distribution and sharing of water for irrigation has been a source of contestations and conflicts. Women who constitute a significant section of irrigation farmers in schemes have been major culprits. The study seeks to analyze gender contestations and conflicts over the use of water in the schemes developed in the Lake Chilwa basin, in southern Malawi. Using oral and written sources as well as drawing evidence from participatory and field observations conducted at Likangala and Domasi irrigation schemes, the largest schemes in the basin, the study observes that women are not passive victims of male domination over the use of dwindling waters for irrigation farming. They have often used existing political and traditional structures developed in the management of water in the schemes to competitively gain monopoly over water. They have sometimes expressed their agency by engaging in irrigation activities that fall beyond the control of formal rules and regulations of irrigation agriculture. Other than being losers, women are winning the battle for water and land resources in the basin.

  12. Valuation of irrigation water in South-western Iran using a hedonic pricing model

    NASA Astrophysics Data System (ADS)

    Esmaeili, Abdoulkarim; Shahsavari, Zahra

    2011-12-01

    Population growth, improved socioeconomic conditions, increased demand for various types of water use, and a reduction in water supply has created more competition for scarce water supplies leveling many countries. Efficient allocation of water supplies between different economic sectors is therefore very important. Water valuation is a useful tool to determine water price. Water pricing can play a major part in improving water allocation by encouraging users to conserve scarce water resources, and promoting improvements in productivity. We used a hedonic pricing method to reveal the implicit value of irrigation water by analyzing agricultural land values in farms under the Doroodzan dam in South-western Iran. The method was applied to farms in which irrigation water came from wells and canals. The availability of irrigation water was one of the most important factors influencing land prices. The value of irrigation water in the farms investigated was estimated to be 0.046 per cubic meter. The estimated price for water was clearly higher than the price farmers currently pay for water in the area of study. Efficient water pricing could help the sustainability of the water resources. Farmers must therefore be informed of the real value of irrigation water used on their land.

  13. Optimal management of water resources demand and supply in irrigated agriculture from plot to regional scale

    NASA Astrophysics Data System (ADS)

    Schütze, Niels; Wagner, Michael

    2016-04-01

    Growing water scarcity in agriculture is an increasing problem in future in many regions of the world. For assessing irrigation as a measure to increase agricultural water security a generalized stochastic optimization framework for a spatial distributed estimation of future irrigation water demand is proposed, which ensures safe yields and a high water productivity at the same time. Different open loop and closed loop control strategies are evaluated within this stochastic optimization framework in order to generate reliable stochastic crop water production functions (SCWPF). The resulting database of SCWPF can serve as a central decision support tool for both, (i) a cost benefit analysis of farm irrigation modernization on a local scale and (ii) a regional water demand management using a multi-scale approach for modeling and implementation. The new approach is applied using the example of a case study in Saxony, which is dealing with the sustainable management of future irrigation water demands and its implementation.

  14. Climate Mitigation Policy Implications for Global Irrigation Water Demand

    SciTech Connect

    Chaturvedi, Vaibhav; Hejazi, Mohamad I.; Edmonds, James A.; Clarke, Leon E.; Kyle, G. Page; Davies, Evan; Wise, Marshall A.

    2013-08-22

    Energy, water and land are scarce resources, critical to humans. Developments in each affect the availability and cost of the others, and consequently human prosperity. Measures to limit greenhouse gas concentrations will inevitably exact dramatic changes on energy and land systems and in turn alter the character, magnitude and geographic distribution of human claims on water resources. We employ the Global Change Assessment Model (GCAM), an integrated assessment model to explore the interactions of energy, land and water systems in the context of alternative policies to limit climate change to three alternative levels: 2.5 Wm-2 (445 ppm CO2-e), 3.5 Wm-2 (535 ppm CO2-e) and 4.5 Wm-2 (645 ppm CO2-e). We explore the effects of alternative land-use emissions mitigation policy options—one which values terrestrial carbon emissions equally with fossil fuel and industrial emissions, and an alternative which places no penalty on land-use change emissions. We find that increasing populations and economic growth could be anticipated to lead to increased demand for water for agricultural systems (+200%), even in the absence of climate change. In general policies to mitigate climate change will increase agricultural demands for water, regardless of whether or not terrestrial carbon is valued or not. Burgeoning demands for water are driven by the demand for bioenergy in response to emissions mitigation policies. We also find that the policy matters. Increases in the demand for water when terrestrial carbon emissions go un-prices are vastly larger than when terrestrial system carbon emissions are prices at the same rate as fossil fuel and industrial emissions. Our estimates for increased water demands when terrestrial carbon systems go un-priced are larger than earlier studies. We find that the deployment of improved irrigation delivery systems could mitigate some of the increase in water demands, but cannot reverse the increases in water demands when terrestrial carbon

  15. Using the soil water balance to analyze the deep percolation losses and the irrigation adequacy of irrigated citrus crops (Haouz plain, Morocco)

    NASA Astrophysics Data System (ADS)

    Nassah, Houda; Fakir, Younes; Er-raki, Salah; Khabba, Said; Merlin, Olivier; Mougenot, Bernard

    2016-04-01

    In the semi-arid Haouz plain, located in central Morocco, agriculture consumes about 85% of the available water resources. Therefore, the management of irrigation water is important to avoid the water loss by soil evaporation and by deep percolation (DP) below the plant root zone. Estimating the irrigation water demand has been investigated by many studies in the Haouz plain, but DP losses beneath the irrigated areas have not been quantified yet. In this context, the objectives of the persent work are threefold :1) to evaluate DP over irrigated citrus orchard under drip and flood irrigation systems using the soil water balance equation; 2) to compare the obtained results to direct measurements of DP by a "flux-meter"; and 3) to optimize the irrigation rates that avoid excessive DP losses and water stress. The results showed that the weekly DP losses vary in average from 15 mm/week to more than 40 mm/week depending to the amount of water supply. The irrigation systems have also an important impact on DP losses evaluated to 38 % in drip irrigation and 12% in flood irrigation. Additionally the density of canopy influences the DP percentage inducing a difference of 10% between the denser citrus site and the sparse one. The comparison of DP losses calculated by soil water balance with those measured by a flux-meter installed beneath the root zone show that the first method gives higher values than the second does. Finally we evaluated the adequacy of the water supply for the crop needs based on two performance indices: depleted fraction (DF) and relative evapotranspiration (RET), showing that the drip irrigation has respond to the culture demands with an excessive quantity of irrigation, unlike to the flood one.

  16. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    NASA Astrophysics Data System (ADS)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two new explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess clear advantages over available alternatives, including: (i) the new solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the new analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  17. Corn yield and water use efficiency under contrasting irrigation application methods: an AquaCrop study contrasting subsurface drip and sprinkler irrigation methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grain corn (Zea mays, L.) is sensitive to soil water availability, which can be influenced by irrigation application method. Four facts motivate deficit irrigation of corn in this region. First, declining Ogallala aquifer well yields limit water availability and thus the area of land that can be irr...

  18. Season-long Changes in Infiltration Rates Associated with Irrigation Water Sodicity and pH

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is increasing need to substitute low quality waters, including saline sodic waters and treated municipal waste water for fresh water when irrigating land in arid and semi-arid regions of the world. In almost all instances low quality waters are more sodic than the fresh waters currently utili...

  19. How much water do we need for irrigation under Climate Change in the Mediterranean?

    NASA Astrophysics Data System (ADS)

    Fader, Marianela; Alberte, Bondeau; Wolfgang, Cramer; Simon, Decock; Sinan, Shi

    2014-05-01

    Anthropogenic climate change will very likely alter the hydrological system of already water-limited agricultural landscapes around the Mediterranean. This includes the need for, as well as the availability of irrigation water. On top of that Mediterranean agroecosystems are very likely to be under strong pressure in the near future through changes in consumer demands and diets, increasing urbanization, demographic change, and new markets for agricultural exportation. As a first step to assess the water demand of the agricultural sector, we use an ecohydrological model (the Lund-Potsdam-Jena managed land model, LPJmL) to estimate current and future irrigation water requirements of this region, considering various climate and socio-economic scenarios. LPJmL is a process-based, agricultural and water balance model, where plant growth is ecophysiologically coupled with hydrological variables. For these simulations, the model was adapted to the Mediterranean region in terms of agrosystems as well as crop parameters, and a sensitivity analysis for the irrigation system efficiency was performed. Patterns of current irrigation water requirements differ strongly spatially within the Mediterranean region depending mainly on potential evapotranspiration, the combination of crops cultivated and the extension of irrigated areas. The simulations for the future indicate that the Mediterranean may need considerable additional amounts of irrigation water. However, the regional patterns differ strongly depending on changes in length of growing periods, changes in transpirational rate (temperature and precipitation change, CO2-fertilization), and the consideration of potential improvements in irrigation system efficiency.

  20. An optimal management of water for a turf irrigation system in Milan area (Italy)

    NASA Astrophysics Data System (ADS)

    Deangelis, Maria Laura; Mazzoleni, Abramo

    2015-04-01

    The design of an irrigation system is not just "draw", but a complex organization that takes into account of a whole range of information that are inherently contained in the graphic representation of the final plan. The various stages that make up the activity of designing an irrigation system include: general survey of the site to be irrigated, meteorological analysis of the site and the calculation of the water requirement, development of the project with the choice and location of the components. The use of a numerical model based on water balance in a soil-water-atmosphere system allows the evaluation of the optimal water requirement as a function of meteorological characteristics. The water saving is enabled through a smart programming of a modern automation system for irrigation. The meteorological data analysis was conducted choosing from the series of two special years: the year 2002, particularly rainy, and the other in 2007, extraordinarily drought. The determination of the water requirements of turf was conducted on a daily scale. The water consumption was calculated in a classic irrigation system that covers the delivery of 5 mm of water per day, interrupted only by a rain sensor. In the second case water consumption was analysed by managing an irrigation controller based on actual water needs of turf day by day. For the two years in question water savings ranges between 13 and 27%.

  1. Modeling to evaluate irrigation management strategies to maximize cotton yield and water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton [Gossypium hirsutum (L.)] grows well under semiarid water stress conditions and is a principal crop on the Southern Great Plains for both dryland and irrigated regimes. Increasing irrigation costs due to high fuel prices and decreasing well capacity of the declining Ogallala Aquifer, compel S...

  2. Water Requirements of Young Blueberry Plants Irrigated by Sprinklers, Microsprays, and Drip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was done to determine the effects of irrigation method on water use by young northern highbush blueberry (Vaccinium corymbosum L. 'Elliott'). Plants were irrigated by overhead sprinkler, microspray, or drip at 50, 100, and 150% of the estimated crop evapotranspiration (ETc) requirement. Du...

  3. Sunflower response to irrigation from limited water supplies with no-till management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limited irrigation necessitates maximizing economic returns by rotating crops, so we conducted a field study during 2005-2009 in southwest Kansas to determine the yield response of sunflower to irrigation and evapotranspiration (ETc) and to measure plant growth parameters and soil water use. Sunflow...

  4. Landscape influences on soil nitrogen supply and water holding capacity for irrigated corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water and nitrogen (N) supply to a crop can interact throughout the growing season to influence yield potential. The increasing availability of variable rate irrigation systems to growers in irrigated regions, along with existing capacity for variable rate fertilization, provides the opportunity for...

  5. Digital-model study of ground-water hydrology, Columbia Basin Irrigation Project Area, Washington

    USGS Publications Warehouse

    Tanaka, H.H.; Hansen, A.J., Jr.; Skrivan, J.A.

    1974-01-01

    Since 1952 water diverted from the Columbia River at Grand Coulee Dam has been used to irrigate parts of the Columbia Basin Irrigation Project area in eastern Washington, and as a result ground-water levels generally have risen in the area. The rapid increases in ground-water inflow, outflow, and storage from irrigation have created a need for a better understanding of the ground-water system before and after the start of irrigation to establish guidelines necessary for management of the area's ground-water resource. Data and information from previous geologic and hydrologic studies were used as a basis for quantitative analyses of ground-water inflow and outflow by means of digital computer models representing three major areas--Quincy Basin, Pasco Basin, and Royal Slope.

  6. Irrigation, plant disease and crop water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 1N Agricultural Reporting District is composed of 23 counties in the northern Texas Panhandle. This region is one of the most agriculturally productive regions in the state because a large percentage of the arable land is irrigated with groundwater from the Ogallala Aquifer. However, irrigated p...

  7. Irrigation science and water quality challenges in Ukbekistan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in Uzbekistan is nearly entirely irrigated due to the semi-arid to arid climate. Similar conditions exist in the U.S. Southern High Plains, and several irrigation crops are important to both regions, including cotton, maize and winter wheat. This presentation discussed cooperative resear...

  8. Evolution of water repellency of organic growing media used in Horticulture and consequences on hysteretic behaviours of the water retention curve

    NASA Astrophysics Data System (ADS)

    Michel, Jean-Charles; Qi, Guifang; Charpentier, Sylvain; Boivin, Pascal

    2010-05-01

    Most of growing media used in horticulture (particularly peat substrates) shows hysteresis phenomena during desiccation and rehydration cycles, which greatly affects their hydraulic properties. The origins of these properties have often been related to one or several of the specific mechanisms such as the non-geometrical uniformity of the pores (also called ‘ink bottle' effect), presence of trapped air, shrinkage-swelling phenomena, and changes in water repellency. However, recent results showed that changes in wettability during desiccation and rehydration could be considered as one of the main factors leading to hysteretic behaviour in these materials with high organic matter contents (Naasz et al., 2008). The general objective was to estimate the evolutions of changes in water repellency on the water retention properties and associated hysteresis phenomena in relation to the intensity and the number of drying/wetting cycles. For this, simultaneous shrinkage/swelling and water retention curves were obtained using method previously developed for soil shrinkage analysis by Boivin (2006) that we have adapted for growing media and to their physical behaviours during rewetting. The experiment was performed in a climatic chamber at 20°C. A cylinder with the growing medium tested was placed on a porous ceramic disk which is used to control the pressure and to full/empty water of the sample. The whole of the device was then placed on a balance to record the water loss/storage with time; whereas linear displacement transducers were used to measure the changes in sample height and diameter upon drying and wetting in the axial and radial directions. Ceramic cups (2 cm long and 0.21 cm diameter) connected to pressure transducers were inserted in the middle of the samples to record the water pressure head. In parallell, contact angles were measured by direct droplet method at different steps during the drying/rewetting cycles. First results obtained on weakly decomposed

  9. Irrigated lands assessment for water management: Technique test. [California

    NASA Technical Reports Server (NTRS)

    Wall, S. L.; Brown, C. E.; Eriksson, M.; Grigg, C. A.; Thomas, R. W.; Colwell, R. N.; Estes, J. E.; Tinney, L. R.; Baggett, J. O.; Sawyer, G.

    1981-01-01

    A procedure for estimating irrigated land using full frame LANDSAT imagery was demonstrated. Relatively inexpensive interpretation of multidate LANDSAT photographic enlargements was used to produce a map of irrigated land in California. The LANDSAT and ground maps were then linked by regression equations to enable precise estimation of irrigated land area by county, basin, and statewide. Land irrigated at least once in California in 1979 was estimated to be 9.86 million acres, with an expected error of less than 1.75% at the 99% level of confidence. To achieve the same level of error with a ground-only sample would have required 3 to 5 times as many ground sample units statewide. A procedure for relatively inexpensive computer classification of LANDSAT digital data to irrigated land categories was also developed. This procedure is based on ratios of MSS band 7 and 5, and gave good results for several counties in the Central Valley.

  10. Changes in soil aggregate stability under different irrigation doses of waste water

    NASA Astrophysics Data System (ADS)

    Morugán, Alicia; García-Orenes, Fuensanta; Mataix-Solera, Jorge; Arcenegui, Victoria; Bárcenas, Gema

    2010-05-01

    Freshwater availability and soil degradation are two of the most important environmental problems in the Mediterranean area acerbated by incorrect agricultural use of irrigation in which organic matter is not correctly managed, the use of low quality water for irrigation, and the inefficiency of dose irrigation. For these reasons strategies for saving water and for the restoration of the mean properties of soil are necessary. The use of treated waste water for the irrigation of agricultural land could be a good solution to these problems, as it reduces the utilization of fresh water and could potentially improve key soil properties. In this work we have been studying, for more than three years, the effects on soil properties of different doses of irrigation with waste water. Here we show the results on aggregate stability. The study is located in an agricultural area at Biar (Alicante, SE of Spain), with a crop of grape (Vitis labrusca). Three types of waters are being used in the irrigation of the soil: fresh water (control) (TC), and treated waste water from secondary (T2) and tertiary treatment (T3). Three different doses of irrigation have been applied to fit the efficiency of the irrigation to the crop and soil type: D10 (10 L m-2 every week during 17 months), D50 (50 L m-2 every fifteen days during 14 moths) and D30 (30 L m-2 every week during 6 months up to present day). The results showed a clear decrease of aggregate stability during the period we used the second dose (D50) independent of the type of water used. That dose of irrigation and frequency produced strong wetting and drying cycles (WD) in the soil, and this is suspected to be the main factor responsible for the results. When we changed the dose of irrigation to D30, reducing the quantity per event and increasing the frequency, the soil aggregate stability started to improve. This dose avoids strong drying periods between irrigation events and the aggregate stability is confirmed to be slowly

  11. Effects of irrigation practices on water use in the groundwater management districts within the Kansas high plains, 1991-2003

    USGS Publications Warehouse

    Perry, Charles A.

    2006-01-01

    Data compiled for the High Plains region of Kansas that includes five Groundwater Management Districts (GMDs) were analyzed for trends in irrigation water use, acres irrigated, precipitation, irrigation system types, and irrigated crop types to determine the effects of irrigation practices on water use over time. For the study period 1991 through 2003, precipitation decreased significantly (with 95-percent confidence) in northwestern and west-central Kansas but not in the southwestern and south-central parts of the State. Irrigation water use had no statistically significant trend during this period. There was a good (R= -0.77) relation between average regional precipitation and total GMD irrigation water use. When irrigation water use was adjusted for this relation, there was a positive trend (90-percent confidence level) in the adjusted irrigation water use. Another adjustment to water use was made using the ratio of annual precipitation to 1991-2005 average precipitation, which resulted in a negative trend (95-percent confidence level) in irrigation water use. This demonstrated the contradictory nature of precipitation adjustments to water use, making their utility somewhat suspect. GMD 3 in southwestern Kansas used 63 percent of the total acre-feet of irrigation water within all the GMDs. When all GMDs are considered, the number of irrigated acres for flood and center pivot systems without drop nozzles decreased significantly during the study period. At the same time the number of drop nozzle irrigated acres increased significantly. The number of irrigated acres of water-intensive crops (corn, alfalfa, and soybeans) also increased significantly, whereas the number of less- or non-water-intensive crops (grain sorghum and wheat), and multiple crop type acres decreased. Drop nozzle irrigation systems used approximately 2 percent less water in a year-by-year comparison than center pivot systems and 8 to 11 percent less water than flood irrigation. The best

  12. Rootzone processes, tree water-use, and the equitable allocation of irrigation water to olives

    NASA Astrophysics Data System (ADS)

    Green, Steve; Clothier, Brent; Caspari, Horst; Neal, Sue

    John Philip's first job in 1947, at Griffith in Australia's Murrumbidgee Irrigation Area, was to develop means by which irrigation practices could become sustainable. Subsequently, through his analytical endeavors he created revolutionary new understanding of mass and energy transfers in the soil-plantatmosphere continuum. Here we describe applications and modeling that have directly benefited from John Philip's insights and perspicacity. We have used a new means for determining the radiation interception by an isolated olive tree, and we have employed these results to interpret and model the measured rates of tree water-use from heat-pulse measures of sapflow. These parameters are used in a risk assessment framework, along with measures of the soil's hydraulic character to provide a basis for establishing guidelines for the equitable and sustainable allocation of water for the irrigation of olive trees in Marlborough, New Zealand. We find that small 2-year old olive trees use about 25 litres a week, whereas mature 8-year old trees transpire about 525 L/wk. Our model developed to establish irrigation allocations, SPASMO, used a 28-year sequence of local weather records. For the Fairhall stony silt loam, we find that an irrigation allocation of 230 mm will meet the needs of olives 9 years in 10. Average requirements would be met with just 140 mm. Only 35 mm would be required to meet the needs of olives 90% of the time on the Woodbourne deep silt loam. Apposite measurements and apt modeling are shown capable of guiding regulatory authorities in managing the complexity of allocating water to olive irrigationists.

  13. Classifying Residents who use Landscape Irrigation: Implications for Encouraging Water Conservation Behavior

    NASA Astrophysics Data System (ADS)

    Warner, Laura A.; Lamm, Alexa J.; Rumble, Joy N.; Martin, Emmett T.; Cantrell, Randall

    2016-08-01

    Large amounts of water applied as urban irrigation can often be reduced substantially without compromising esthetics. Thus, encouraging the adoption of water-saving technologies and practices is critical to preserving water resources, yet difficult to achieve. The research problem addressed in this study is the lack of characterization of residents who use urban irrigation, which hinders the design of effective behavior change programs. This study examined audience segmentation as an approach to encouraging change using current residential landscape practices. K-means cluster analysis identified three meaningful subgroups among residential landscape irrigation users ( N = 1,063): the water considerate majority ( n = 479, 45 %), water savvy conservationists ( n = 378, 36 %), and unconcerned water users ( n = 201, 19 %). An important finding was that normative beliefs, attitudes, and perceived behavioral control characteristics of the subgroups were significantly different with large and medium practical effect sizes. Future water conservation behaviors and perceived importance of water resources were also significantly different among subgroups. The water considerate majority demonstrated capacity to conserve, placed high value on water, and were likely to engage in behavior changes. This article contributes to the literature on individuals who use residential landscape irrigation, an important target audience with potential to conserve water through sustainable irrigation practices and technologies. Findings confirm applicability of the capacity to conserve water to audience segmentation and extend this concept by incorporating perceived value of water resources and likelihood of conservation. The results suggest practical application to promoting residential landscape water conservation behaviors based on important audience characteristics.

  14. Hydrochemical assessment of water quality for irrigation: a case study of the Medjerda River in Tunisia

    NASA Astrophysics Data System (ADS)

    Etteieb, Selma; Cherif, Semia; Tarhouni, Jamila

    2015-02-01

    In order to characterize, classify and evaluate the suitability of Medjerda River water for irrigation, a hydrochemical assessment was conducted. It accounts for 80 % of the total Tunisian surface water. In this paper, hydrographical methods and PHREEQC geochemical program were used to characterize water quality of Medjerda River, whereas its suitability for irrigation was determined in accordance with its electrical conductivity (EC), sodium adsorption ratio (SAR) and sodium concentrations. It was established that the water samples were undersaturated with calcite, dolomite, aragonite, anhydrite, gypsum and halite except in one water sample which is supersaturated with carbonate minerals. The quality assessment of Medjerda River for irrigation purposes showed that some points belonged to the excellent-to-good and good-to-permissible irrigation water categories, while the remaining ones were classified as doubtful to unsuitable for irrigation making the river water use limited to plants with high salt tolerance. Moreover, based on FAO guidelines, almost all water samples may cause immediate salinity to gradual increasing problem but no soil infiltration problems except for two sampling points. However, immediate development or possible increasing of severe toxicity problems may be caused by the continuous use of this water for irrigation due to troublesome concentrations of chloride and sodium.

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

    PubMed

    Allende, Ana; Monaghan, James

    2015-07-01

    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

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

    PubMed Central

    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

  17. Spatio-temporal estimation of consumptive water use for assessment of irrigation system performance and management of water resources in irrigated Indus Basin, Pakistan

    NASA Astrophysics Data System (ADS)

    Usman, M.; Liedl, R.; Awan, U. K.

    2015-06-01

    Reallocation of water resources in any irrigation scheme is only possible by detailed assessment of current irrigation performance. The performance of the Lower Chenab Canal (LCC) irrigation system in Pakistan was evaluated at large spatial and temporal scales. Evaporative Fraction (EF) representing the key element to assess the three very important performance indicators of equity, adequacy and reliability, was determined by the Surface Energy Balance Algorithm (SEBAL) using Moderate Resolution Imaging Spectroradiometer (MODIS) images. Spatially based estimations were performed at irrigation subdivisions, lower and upper LCC and, whole LCC scales, while temporal scales covered months, seasons and years for the study period from 2005 to 2012. Differences in consumptive water use between upper and lower LCC were estimated for different crops and possible water saving options were explored. The assessment of equitable water distribution indicates smaller coefficients of variation and hence less inequity within each subdivision except Sagar (0.08) and Bhagat (0.10). Both adequacy and reliability of water resources are found lower during kharif as compared to rabi with variation from head to tail reaches. Reliability is quite low from July to September and in February/March. This is mainly attributed to seasonal rainfalls. Average consumptive water use estimations indicate almost doubled water use (546 mm) in kharif as compared to (274 mm) in rabi with significant variability for different cropping years. Crop specific consumptive water use reveals rice and sugarcane as major water consumers with average values of 593 mm and 580 mm, respectively, for upper and lower LCC, followed by cotton and kharif fodder. The water uses for cotton are 555 mm and 528 mm. For kharif fodder, corresponding values are 525 mm and 494 mm for both regions. Based on the differences in consumptive water use, different land use land cover change scenarios were evaluated with regard to savings

  18. Regulated deficit irrigation (RDI) to save water and improve Sauvignon Blanc quality?

    PubMed

    Greven, M; Green, S; Neal, S; Clothier, B; Neal, M; Dryden, G; Davidson, P

    2005-01-01

    With a fast change of land use in Marlborough from extensive pastoral farming to intensive irrigated viticulture, a need has risen to investigate the sustainable use of the available water. In 2001 a 5 ha irrigation research project was installed in a Marlborough Sauvignon Blanc vineyard. Irrigation treatments installed were control (compensate 100% for crop evapotranspiration (ET(O)), 80%, 70% and 60% of ET(O). During the two years that the Regulated Deficit Irrigation (RDI) trial has run so far, very different climatic conditions created much greater differences in yield and vegetative growth, than up to 40% reduction in irrigation, none of which were significant. The use of sap flow in the vines has been fine-tuned and is now giving reliable results on which to base vine water need. PMID:15771094

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. Decentralising Zimbabwe’s water management: The case of Guyu-Chelesa irrigation scheme

    NASA Astrophysics Data System (ADS)

    Tambudzai, Rashirayi; Everisto, Mapedza; Gideon, Zhou

    Smallholder irrigation schemes are largely supply driven such that they exclude the beneficiaries on the management decisions and the choice of the irrigation schemes that would best suit their local needs. It is against this background that the decentralisation framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasise the need for a participatory approach to water management. The Zimbabwean government has gone a step further in decentralising the management of irrigation schemes, that is promoting farmer managed irrigation schemes so as to ensure effective management of scarce community based land and water resources. The study set to investigate the way in which the Guyu-Chelesa irrigation scheme is managed with specific emphasis on the role of the Irrigation Management Committee (IMC), the level of accountability and the powers devolved to the IMC. Merrey’s 2008 critique of IWRM also informs this study which views irrigation as going beyond infrastructure by looking at how institutions and decision making processes play out at various levels including at the irrigation scheme level. The study was positioned on the hypothesis that ‘decentralised or autonomous irrigation management enhances the sustainability and effectiveness of irrigation schemes’. To validate or falsify the stated hypothesis, data was gathered using desk research in the form of reviewing articles, documents from within the scheme and field research in the form of questionnaire surveys, key informant interviews and field observation. The Statistical Package for Social Sciences was used to analyse data quantitatively, whilst content analysis was utilised to analyse qualitative data whereby data was analysed thematically. Comparative analysis was carried out as Guyu-Chelesa irrigation scheme was compared with other smallholder irrigation scheme’s experiences within Zimbabwe and the Sub Saharan African region at large. The findings were that whilst the

  1. Deep subsurface drip irrigation using coal-bed sodic water: part II. geochemistry

    USGS Publications Warehouse

    Bern, Carleton R.; Breit, George N.; Healy, Richard W.; Zupancic, John W.

    2013-01-01

    Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm-1) and high-SAR (54) waters are co-produced with coal-bed methane and some are used for subsurface drip irrigation(SDI). The SDI system studied mixes sulfuric acid with irrigation water and applies water year-round via drip tubing buried 92 cm deep. After six years of irrigation, SAR values between 0 and 30 cm depth (0.5-1.2) are only slightly increased over non-irrigated soils (0.1-0.5). Only 8-15% of added Na has accumulated above the drip tubing. Sodicity has increased in soil surrounding the drip tubing, and geochemical simulations show that two pathways can generate sodic conditions. In soil between 45-cm depth and the drip tubing, Na from the irrigation water accumulates as evapotranspiration concentrates solutes. SAR values >12, measured by 1:1 water-soil extracts, are caused by concentration of solutes by factors up to 13. Low-EC (-1) is caused by rain and snowmelt flushing the soil and displacing ions in soil solution. Soil below the drip tubing experiences lower solute concentration factors (1-1.65) due to excess irrigation water and also contains relatively abundant native gypsum (2.4 ± 1.7 wt.%). Geochemical simulations show gypsum dissolution decreases soil-water SAR to 14 and decreasing EC in soil water to 3.2 mS cm-1. Increased sodicity in the subsurface, rather than the surface, indicates that deep SDI can be a viable means of irrigating with sodic waters.

  2. Can E. coli or thermotolerant coliform concentrations predict pathogen presence or prevalence in irrigation waters?

    PubMed

    Pachepsky, Yakov; Shelton, Daniel; Dorner, Sarah; Whelan, Gene

    2016-05-01

    An increase in food-borne illnesses in the United States has been associated with fresh produce consumption. Irrigation water presents recognized risks for microbial contamination of produce. Water quality criteria rely on indicator bacteria. The objective of this review was to collate and summarize experimental data on the relationships between pathogens and thermotolerant coliform (THT) and/or generic E. coli, specifically focusing on surface fresh waters used in or potentially suitable for irrigation agriculture. We analyzed peer-reviewed publications in which concentrations of E. coli or THT coliforms in surface fresh waters were measured along with concentrations of one or more of waterborne and food-borne pathogenic organisms. The proposed relationships were significant in 35% of all instances and not significant in 65% of instances. Coliform indicators alone cannot provide conclusive, non-site-specific and non-pathogen-specific information about the presence and/or concentrations of most important pathogens in surface waters suitable for irrigation. Standards of microbial water quality for irrigation can rely not only on concentrations of indicators and/or pathogens, but must include references to crop management. Critical information on microbial composition of actual irrigation waters to support criteria of microbiological quality of irrigation waters appears to be lacking and needs to be collected. PMID:25198779

  3. [Effect of Recycled Water Irrieation on Heavy Metal Pollution in Irrigation Soil].

    PubMed

    Zhou, Yi-qi; Liu, Yun-xia; Fu, Hui-min

    2016-01-15

    With acceleration of urbanization, water shortages will become a serious problem. Usage of reclaimed water for flushing and watering of the green areas will be common in the future. To study the heavy metal contamination of soils after green area irrigation using recycled wastewater from special industries, we selected sewage and laboratory wastewater as water source for integrated oxidation ditch treatment, and the effluent was used as irrigation water of the green area. The irrigation units included broad-leaved forest, bush and lawn. Six samples sites were selected, and 0-20 cm soil of them were collected. Analysis of the heavy metals including Cr, Mn, Ni, Cu, Zn, As, Cd and Pb in the soil showed no significant differences with heavy metals concentration in soil irrigated with tap water. The heavy metals in the soil irrigated with recycled water were mainly enriched in the surface layer, among which the contents of Cr, Ni, Cu, Zn and Pb were below the soil background values of Beijing. A slight pollution of As and Cd was found in the soil irrigated by recycled water, which needs to be noticed. PMID:27078969

  4. [Soil salinity in greenland irrigated with reclaimed water and risk assessment].

    PubMed

    Pan, Neng; Chen, Wei-Ping; Jiao, Wen-Tao; Zhao, Zhong-Ming; Hou, Zhen-An

    2012-12-01

    Compared to drinking water or groundwater, reclaimed water contains more salts. Therefore, the effects of application of reclaimed water on the soil salinity have received great attentions. To evaluate the potential risks posed by long-term reclaimed water irrigation, we collected surface soil samples from urban green lands and suburban farmlands of Beijing represented different irrigation durations. The electrical conductivity (EC) and sodium adsorption ratio (SAR) in soils were measured subsequently. Both EC1:5 and SAR1.5 from the green land and farmland soils irrigated with reclaimed water were significantly higher than those of control treatments (drinking water or groundwater irrigation). The EC1:5 values increased by 12.4% and 84.2% than control treatments in the greenland and farmland, respectively. The SAR1:5 values increased by 64.5% and 145.8% than control treatments, respectively. No significant differences of both EC1:5 and SAR1:5 were found between of 0-10 cm and 10-20 cm soil layer. A slight decrease of soil porosity was observed. The field investigation suggested there was a high potential of soil salinization under long-term reclaimed water irrigation. Proper management practices should be implemented to minimize the soil salinity accumulation risk when using reclaimed water for irrigation in Beijing. PMID:23379127

  5. Rice performance and water use efficiency under plastic mulching with drip irrigation.

    PubMed

    He, Haibing; Ma, Fuyu; Yang, Ru; Chen, Lin; Jia, Biao; Cui, Jing; Fan, Hua; Wang, Xin; Li, Li

    2013-01-01

    Plastic mulching with drip irrigation is a new water-saving rice cultivation technology, but little is known on its productivity and water-saving capacity. This study aimed to assess the production potential, performance, and water use efficiency (WUE) of rice under plastic mulching with drip irrigation. Field experiments were conducted over 2 years with two rice cultivars under different cultivation systems: conventional flooding (CF), non-flooded irrigation incorporating plastic mulching with furrow irrigation (FIM), non-mulching with furrow irrigation (FIN), and plastic mulching with drip irrigation (DI). Compared with the CF treatment, grain yields were reduced by 31.76-52.19% under the DI treatment, by 57.16-61.02% under the FIM treatment, by 74.40-75.73% under the FIN treatment, which were mainly from source limitation, especially a low dry matter accumulation during post-anthesis, in non-flooded irrigation. WUE was the highest in the DI treatment, being 1.52-2.12 times higher than with the CF treatment, 1.35-1.89 times higher than with the FIM treatment, and 2.37-3.78 times higher than with the FIN treatment. The yield contribution from tillers (YCFTs) was 50.65-62.47% for the CF treatment and 12.07-20.62% for the non-flooded irrigation treatments. These low YCFTs values were attributed to the poor performance in tiller panicles rather than the total tiller number. Under non-flooded irrigation, root length was significantly reduced with more roots distributed in deep soil layers compared with the CF treatment; the DI treatment had more roots in the topsoil layer than the FIM and FIN treatments. The experiment demonstrates that the DI treatment has greater water saving capacity and lower yield and economic benefit gaps than the FIM and FIN treatments compared with the CF treatment, and would therefore be a better water-saving technology in areas of water scarcity. PMID:24340087

  6. Reimagining cost recovery in Pakistan's irrigation system through willingness-to-pay estimates for irrigation water from a discrete choice experiment

    NASA Astrophysics Data System (ADS)

    Bell, Andrew Reid; Shah, M. Azeem Ali; Ward, Patrick S.

    2014-08-01

    It is widely argued that farmers are unwilling to pay adequate fees for surface water irrigation to recover the costs associated with maintenance and improvement of delivery systems. In this paper, we use a discrete choice experiment to study farmer preferences for irrigation characteristics along two branch canals in Punjab Province in eastern Pakistan. We find that farmers are generally willing to pay well in excess of current surface water irrigation costs for increased surface water reliability and that the amount that farmers are willing to pay is an increasing function of their existing surface water supply as well as location along the main canal branch. This explicit translation of implicit willingness-to-pay (WTP) for water (via expenditure on groundwater pumping) to WTP for reliable surface water demonstrates the potential for greatly enhanced cost recovery in the Indus Basin Irrigation System via appropriate setting of water user fees, driven by the higher WTP of those currently receiving reliable supplies.

  7. Reimagining cost recovery in Pakistan's irrigation system through willingness-to-pay estimates for irrigation water from a discrete choice experiment

    PubMed Central

    Bell, Andrew Reid; Shah, M Azeem Ali; Ward, Patrick S

    2014-01-01

    It is widely argued that farmers are unwilling to pay adequate fees for surface water irrigation to recover the costs associated with maintenance and improvement of delivery systems. In this paper, we use a discrete choice experiment to study farmer preferences for irrigation characteristics along two branch canals in Punjab Province in eastern Pakistan. We find that farmers are generally willing to pay well in excess of current surface water irrigation costs for increased surface water reliability and that the amount that farmers are willing to pay is an increasing function of their existing surface water supply as well as location along the main canal branch. This explicit translation of implicit willingness-to-pay (WTP) for water (via expenditure on groundwater pumping) to WTP for reliable surface water demonstrates the potential for greatly enhanced cost recovery in the Indus Basin Irrigation System via appropriate setting of water user fees, driven by the higher WTP of those currently receiving reliable supplies. PMID:25552779

  8. DEMONSTRATION OF IRRIGATION RETURN FLOW WATER QUALITY CONTROL IN THE MESILLA VALLEY, NEW MEXICO

    EPA Science Inventory

    A 182-ha operating farm was used to demonstrate the water pollution control benefits of implementing improved irrigation management techniques and structures. The commodity crops produced on the farm included wheat, tomatoes, cotton, lettuce, peppers, chiles, grain sorghum, and a...

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

    NASA Astrophysics Data System (ADS)

    Tanji, Hajime; Kiri, Hirohide; Kobayashi, Shintaro

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

  10. IRRIMET: a web 2.0 advisory service for irrigation water management

    NASA Astrophysics Data System (ADS)

    De Michele, Carlo; Anzano, Enrico; Colandrea, Marco; Marotta, Luigi; Mula, Ileana; Pelosi, Anna; D'Urso, Guido; Battista Chirico, Giovanni

    2016-04-01

    Irrigation agriculture is one the biggest consumer of water in Europe, especially in southern regions, where it accounts for up to 70% of the total water consumption. The EU Common Agricultural Policy, combined with the Water Framework Directive, imposes to farmers and irrigation managers a substantial increase of the efficiency in the use of water in agriculture for the next decade. Irrigating according to reliable crop water requirement estimates is one of the most convincing solution to decrease agricultural water use. Here we present an innovative irrigation advisory service, applied in Campania region (Southern Italy), where a satellite assisted irrigation advisory service has been operating since 2006. The advisory service is based on the optimal combination of VIS-NIR high resolution satellite images (Landsat, Deimos, Rapideye) to map crop vigour, and high resolution numerical weather prediction for assessing the meteorological variables driving the crop water needs in the short-medium range. The advisory service is broadcasted with a simple and intuitive web app interface which makes daily real time irrigation and evapotranspiration maps and customized weather forecasts (based on Cosmo Leps model) accessible from desktop computers, tablets and smartphones.

  11. Effects of irrigation pumping on the ground-water system in Newton and Jasper Counties, Indiana

    USGS Publications Warehouse

    Bergeron, Marcel P.

    1981-01-01

    Flow in the ground-water system in Newton and Jasper Counties, Indiana, was simulated in a quasi-three-dimensional model in a study of irrigation use of ground water in the two counties. The ground-water system consists of three aquifers: (1) a surficial coarse sand aquifer known as the Kankakee aquifer, (2) a limestone and dolomite bedrock aquifer, and (3) a sand and gravel bedrock valley aquifer. Irrigation pumping, derived primarily from the bedrock, was estimated to be 34.8 million gallons per day during peak irrigation in 1977. Acreage irrigated with ground water is estimated to be 6,200 acres. A series of model experiments was used to estimate the effects of irrigation pumping on ground-water levels and streamflow. Model analysis indicates that a major factor controlling drawdown due to pumping in the bedrock aquifer are the variations in thickness and in vertical hydraulic conductivity in a semiconfining unit overlying the bedrock. Streamflow was not significantly reduced by hypothetical withdrawals of 12.6 million gallons per day from the bedrock aquifer and 10.3 million gallons per day in the Kankakee aquifer. Simulation of water-level recovery after irrigation pumping indicated that a 5-year period of alternating between increasing pumping and recovery will not cause serious problems of residual drawdown or ground-water mining. 

  12. Estimating Irrigation Water Requirements using MODIS Vegetation Indices and Inverse Biophysical Modeling

    NASA Technical Reports Server (NTRS)

    Imhoff, Marc L.; Bounoua, Lahouari; Harriss, Robert; Harriss, Robert; Wells, Gordon; Glantz, Michael; Dukhovny, Victor A.; Orlovsky, Leah

    2007-01-01

    An inverse process approach using satellite-driven (MODIS) biophysical modeling was used to quantitatively assess water resource demand in semi-arid and arid agricultural lands by comparing the carbon and water flux modeled under both equilibrium (in balance with prevailing climate) and non-equilibrium (irrigated) conditions. Since satellite observations of irrigated areas show higher leaf area indices (LAI) than is supportable by local precipitation, we postulate that the degree to which irrigated lands vary from equilibrium conditions is related to the amount of irrigation water used. For an observation year we used MODIS vegetation indices, local climate data, and the SiB2 photosynthesis-conductance model to examine the relationship between climate and the water stress function for a given grid-cell and observed leaf area. To estimate the minimum amount of supplemental water required for an observed cell, we added enough precipitation to the prevailing climatology at each time step to minimize the water stress function and bring the soil to field capacity. The experiment was conducted on irrigated lands on the U.S. Mexico border and Central Asia and compared to estimates of irrigation water used.

  13. An appraisal of ground water for irrigation in the Wadena area, central Minnesota

    USGS Publications Warehouse

    Lindholm, F.G.

    1970-01-01

    Analyses were made to determine effects of development on ground-water levels under different development schemes both after a single irrigation season and after 5 and 20 successive years of irrigation. Where development is concentrated, some interference between wells can be expected. Although water levels recover rapidly when pumps are shut off, recovery will not be complete prior to the next irrigation season in heavily developed areas. After several years of watertable lowering, yields from wells will decrease because of deceased saturated thickness, unless climatic changes result in abnormally high amounts of recharge.

  14. Is Improving Field Irrigation Efficiency the Panacea for Water Scarcity? the Case of Egypt

    NASA Astrophysics Data System (ADS)

    Theodore, C.; Steenhuis, T. S.

    2011-12-01

    Water is becoming scarce resource throughout the world with the Mediterranean Sea basin as one of the most water limiting regions in the world. Desalinization and improving irrigation efficiency are two of the possibilities mentioned for decreasing water scarcity. In this presentation we will use Egypt as an example to explore the effect of improving field irrigation efficiencies. In Egypt and the economy with 83 million people entirely depends on the Nile of which 85% of the water originates in Ethiopia. The water in the Egypt is regulated by Lake Nasser smoothing out the runoff peaks to an even flow of approximately 0.16 BCM per day. This water is mainly used for irrigation, industrial and municipal uses. Approximately between 5.4 and 6 million ha are irrigated along the Nile and in the delta. Less than 20% of the Nile flow at the Aswan dam enters the Mediterranean Sea and is highly polluted. Irrigation practices in Egypt are highly inefficient with field efficiencies in the order of 70%. It has been suggested that increasing efficiencies will increase water availability down stream. In order to understand if this is possible, we considered the fate of the irrigation water. Part of the water applied to the field evaporates and the remaining water percolates downward and recharges the aquifer. The aquifer supplies base flow to the Nile and provides water for irrigation. Thus the only loss of the system is the evaporation from the crop in the field. Using this fact we can estimate the overall irrigation efficiency of the irrigation in the Nile. If we assume that 98% of the cultivated land are irrigated with an average evaporation rate of 1150 mm we find that the agricultural water use is at the same order as the water released at the Aswan dam. Assuming that all other uses are also conservative (i.e. use the water and return it back to the Nile with some pollution), we see that the overall use is over 100% during some years. This is not possible so not all land is

  15. Responses of Winter Wheat Yield and Water Use Efficiency to Irrigation Frequency and Planting Pattern

    PubMed Central

    Bian, Chengyue; Ma, Changjian; Liu, Xinhui; Gao, Chao; Liu, Quanru; Yan, Zhenxing; Ren, Yujie; Li, Quanqi

    2016-01-01

    A suitable planting pattern and irrigation strategy are essential for optimizing winter wheat yield and water use efficiency (WUE). The study aimed to evaluate the impact of planting pattern and irrigation frequency on grain yield and WUE of winter wheat. During the 2013–2014 and 2014–2015 winter wheat growing seasons in the North China Plain, the effects of planting patterns and irrigation frequencies were determined on tiller number, grain yield, and WUE. The two planting patterns tested were wide-precision and conventional-cultivation. Each planting pattern had three irrigation regimes: irrigation (120 mm) at the jointing stage; irrigation (60 mm) at both the jointing and heading stages; and irrigation (40 mm) at the jointing, heading, and milking stages. In our study, tiller number was significantly higher in the wide-precision planting pattern than in the conventional-cultivation planting pattern. Additionally, the highest grain yields and WUE were observed when irrigation was applied at the jointing stage (120 mm) or at the jointing and heading stages (60 mm each) in the wide-precision planting pattern. These results could be attributed to higher tiller numbers as well as reduced water consumption due to reduced irrigation frequency. In both growing seasons, applying 60 mm of water at jointing and heading stages resulted in the highest grain yield among the treatments. Based on our results, for winter wheat production in semi-humid regions, we recommend a wide-precision planting pattern with irrigation (60 mm) at both the jointing and heading stages. PMID:27171202

  16. Horticulture/Floriculture.

    ERIC Educational Resources Information Center

    Lehigh County Area Vocational-Technical School, Schnecksville, PA.

    This brochure describes the philosophy and scope of a secondary-level course in floriculture and horticulture. Addressed in the individual units of the course are the following topics: the Future Farmers of America, floriculture, merchandising and selling, retail flower shop management, advertising, inventory, indentification of common floral…

  17. Use of magnesia for boron removal from irrigation water.

    PubMed

    Dionisiou, Nina; Matsi, Theodora; Misopolinos, Nikolaos D

    2006-01-01

    The risk of B phytotoxicity due to high levels of B in irrigation water can be avoided by removing B from the water, before its use, through adsorption on certain adsorbents, such as magnesia (industrial MgO), if the latter can be proven to be an effective and easy to handle means for B removal. In addition, if such a material is applied as a fertilizer after its use and the adsorbed B is easily released into the soil solution, B phytotoxicity could constitute a potential hazard. The objectives of this work were to: (a) establish the optimum working conditions (equilibration time, solution to adsorbent ratio, and particle size of the adsorbent) for B adsorption, (b) assess the magnitude of B adsorption by magnesia, both in capacity and intensity terms, as well as the influence of temperature, (c) study B desorbability from magnesia, spiked with B at two rates, 5 and 0.5 mg g(-1), and (d) compare the results from b and c to those obtained using reagent grade MgO. The results showed that the time to achieve equilibrium depended on the B concentration of the external solution and ranged from 6 h (for B /= 50 mg L(-1)). The percentage of B adsorbed decreased as the volume of external solution to adsorbent increased and a working ratio of 50:1 was selected. For magnesia, B adsorption was particle size dependent with the smallest fraction (<0.1 mm) sorbing more B than the other three fractions studied (0.1-1.0, 1.1-2.0, 2.1-4.0 mm). Boron adsorption was conducted under strongly alkaline pH (10.3 +/- 0.2 and 10.4 +/- 0.1 for the reagent and magnesia, respectively) and increased with temperature. Both adsorbents exhibited a high B adsorption capacity (Langmuir maximum values were 5.85 +/- 0.39 and 4.45 +/- 1.31 mg B g(-1) for the reagent and magnesia, respectively) comparable to other metal oxides. However, the reagent grade MgO seemed to be superior to magnesia in terms of capacity and strength of B retention. This superiority of the

  18. The effect of a disinfectant/coolant irrigant on microbes isolated from dental unit water lines.

    PubMed

    Epstein, Joel B; Dawson, J R; Buivids, Ilze A; Wong, Bea; Le, Nhu D

    2002-01-01

    The purpose of this study was to assess water samples from a hospital dental clinic to determine whether a disinfectant/coolant irrigant containing chlorhexidine (Lines, Micrylium Laboratories) affects the presence of microbial organisms in dental unit waterlines. Water samples from three hospital dental operatories were collected at baseline and after overnight treatment with a disinfectant-containing irrigant followed by sterile water irrigation. Saliva of treated patients and sterile water rinse specimens were collected from the waterlines of these operatories for three consecutive days, then weekly for eight weeks after treatment. Specimens were cultured to identify total heterotrophic plate counts as well as presence of Pseudomonas aeruginosa and Candida species. Baseline organism counts varied from 10(3) to 10(5) colony-forming units per milliliter. After treatment, no organisms were detected in waterline discharge. Decontamination of dental unit waterlines is possible using a disinfectant/irrigant followed by sterile water irrigation. The potential for contamination of the lines from patients' saliva may have been reduced due to use of anti-retraction valves and the disinfectant/sterile water irrigation, as conducted in this study. PMID:12449456

  19. Sustainability of agriculture under irrigation: Use and management of degraded water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In arid regions the use of saline and reclaimed waters for irrigation is increasingly necessary. Scarcity of fresh water for agriculture is increased by the water demands of the municipal and industrial sectors. In the majority of these regions there is a rapid decrease in fresh water availability ...

  20. Mathematical models of water application for a variable rate irrigating hill-seeder

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variable rate irrigating hill-seeder can adjust water application automatically according to the difference in soil moisture content in the field to alleviate drought and save water. Two key problems to realize variable rate water application are how to determine the right amount of water for the ...

  1. Modeling the effects of irrigation frequencies, initial water and nitrogen on corn yield responses for best management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Competing demands for fresh water resources necessitate adaptation of limited water irrigations in agriculture. In this context, the Crop Water Production Functions (CWPF) used in limited water irrigation management need to integrate the effects of climate, initial soil water content at planting, an...

  2. A modeling study of irrigation effects on global surface water and groundwater resources under a changing climate

    SciTech Connect

    Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Leung, Lai-Yung R.

    2015-08-25

    In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumping scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change impact

  3. A modeling study of irrigation effects on global surface water and groundwater resources under a changing climate

    DOE PAGESBeta

    Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Leung, Lai-Yung R.

    2015-08-25

    In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumpingmore » scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change

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

    NASA Astrophysics Data System (ADS)

    Nolz, Reinhard; Loiskandl, Willibald

    2016-04-01

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

  5. Crop And Irrigation Water Management Using High Resolution Remote Sensing And Agrohydrological Models

    NASA Astrophysics Data System (ADS)

    Minacapilli, M.; Iovino, M.; D'Urso, G.

    2006-08-01

    A combined agrohydrological and remote sensing approach, called SIMODIS (Simulation and Management of On-Demand Irrigation Systems) (D'Urso, 2001), has been used in a Sicilian test area to simulate the operation of on-demand irrigation system. In SIMODIS the spatial distribution of crop factor, Kc, is directly calculated from canopy variables r (albedo), LAI (Leaf Area Index) and hc (crop height) derived from satellite-based canopy spectral reflectance. Coupling these canopy variables with a specific data set of soil properties, the SIMODIS procedure was setup to simulate, in a distributed way, the water balance and, therefore, the irrigation deliveries for a set of 136 grape fields. For the 2002 irrigation season a good agreement was found between measured and simulated irrigation deliveries both at district and secondary unit level. At these scales, the proposed approach is able to describe the behaviour of on-demand irrigation systems and can be a useful support to irrigation technicians who have to take decisions for improving the efficiency of irrigation systems.

  6. Toxicity assessment of oil field produced water treated by evaporative processes to produce water to irrigation.

    PubMed

    Andrade, V T; Andrade, B G; Costa, B R S; Pereira, O A; Dezotti, M

    2010-01-01

    During the productive life of an oil well, a high quantity of produced water is extracted together with the oil, and it may achieve up to 99% in the end of the well's economical life. Desalination is one of mankind's earliest forms of saline water treatment, and nowadays, it is still a common process used throughout the world. A single-effect mechanical vapor compression (MVC) process was tested. This paper aims to assess the potential toxicity of produced water to be re-used in irrigation. Samples of both produced and distilled water were evaluated by 84 chemical parameters. The distilled produced water presented a reduction up to 97% for the majority of the analyzed parameters, including PAHs. Toxicity bioassays were performed with distilled produced water to evaluate the growth inhibition of Pseudokirchneriella subcapitata algae, the acute toxicity to Danio rerio fish, the germination inhibition of Lactuca sativa vegetable and the severity of toxicity, as well as behavior test with Lumbricid Earthworm Eisenia fetida. The ecotoxicological assays results showed no toxicity, indicating that the referred evaporative process can produce water to be reused in irrigation. PMID:20706017

  7. Red cabbage yield, heavy metal content, water use and soil chemical characteristics under wastewater irrigation.

    PubMed

    Tunc, Talip; Sahin, Ustun

    2016-04-01

    The objective of this 2-year field study was to evaluate the effects of drip irrigation with urban wastewaters reclaimed using primary (filtration) and secondary (filtration and aeration) processes on red cabbage growth and fresh yield, heavy metal content, water use and efficiency and soil chemical properties. Filtered wastewater (WW1), filtered and aerated wastewater (WW2), freshwater and filtered wastewater mix (1:1 by volume) (WW3) and freshwater (FW) were investigated as irrigation water treatments. Crop evapotranspiration decreased significantly, while water use efficiency increased under wastewater treatments compared to FW. WW1 treatment had the lowest value (474.2 mm), while FW treatments had the highest value (556.7 mm). The highest water use efficiency was found in the WW1 treatment as 8.41 kg m(-3), and there was a twofold increase with regard to the FW. Wastewater irrigation increased soil fertility and therefore red cabbage yield. WW2 treatment produced the highest total fresh yield (40.02 Mg ha(-1)). However, wastewater irrigation increased the heavy metal content in crops and soil. Cd content in red cabbage heads was above the safe limit, and WW1 treatment had the highest value (0.168 mg kg(-1)). WW3 treatment among wastewater treatments is less risky in terms of soil and crop heavy metal pollution and faecal coliform contamination. Therefore, WW3 wastewater irrigation for red cabbage could be recommended for higher yield and water efficiency with regard to freshwater irrigation. PMID:26611631

  8. Irrigation Trials for ET Estimation and Water Management in California Specialty Crops

    NASA Astrophysics Data System (ADS)

    Johnson, L.; Cahn, M.; Martin, F.; Lund, C.; Melton, F. S.

    2012-12-01

    Accurate estimation of crop evapotranspiration (ETc) can support efficient irrigation water management, which in turn brings benefits including surface water conservation, mitigation of groundwater depletion/degradation, energy savings, and crop quality assurance. Past research in California has revealed strong relationships between canopy fractional cover (Fc) and ETc of certain specialty crops, while additional research has shown the potential of monitoring Fc by satellite remote sensing. California's Central Coast is the leading region of cool season vegetable production in the U.S. Monterey County alone produces more than 80,000 ha of lettuce and broccoli (about half of U.S. production), valued at $1.5 billion in 2009. Under this study, we are conducting ongoing irrigation trials on these crops at the USDA Agricultural Research Station (Salinas) to compare irrigation scheduling via plant-based ETc approaches, by way of Fc, with current industry standard-practice. The following two monitoring approaches are being evaluated - 1) a remote sensing model employed by NASA's prototype Satellite Irrigation Management System, and 2) an online irrigation scheduling tool, CropManage, recently developed by U.C. Cooperative Extension. Both approaches utilize daily grass-reference ETo data as provided by the California Irrigation Management Irrigation System (CIMIS). A sensor network is deployed to monitor applied irrigation, volumetric soil water content, soil water potential, deep drainage, and standard meteorologic variables in order to derive ETc by a water balance approach. Evaluations of crop yield and crop quality are performed by the research team and by commercial growers. Initial results to-date indicate that applied water reductions based on Fc measurements are possible with little-to-no impact on yield of crisphead lettuce (Lactuca sativa). Additional results for both lettuce and broccoli trials, conducted during summer-fall 2012, are presented with respect to

  9. Integration of soil moisture and geophysical datasets for improved water resource management in irrigated systems

    NASA Astrophysics Data System (ADS)

    Finkenbiner, Catherine; Franz, Trenton E.; Avery, William Alexander; Heeren, Derek M.

    2016-04-01

    Global trends in consumptive water use indicate a growing and unsustainable reliance on water resources. Approximately 40% of total food production originates from irrigated agriculture. With increasing crop yield demands, water use efficiency must increase to maintain a stable food and water trade. This work aims to increase our understanding of soil hydrologic fluxes at intermediate spatial scales. Fixed and roving cosmic-ray neutron probes were combined in order to characterize the spatial and temporal patterns of soil moisture at three study sites across an East-West precipitation gradient in the state of Nebraska, USA. A coarse scale map was generated for the entire domain (122 km2) at each study site. We used a simplistic data merging technique to produce a statistical daily soil moisture product at a range of key spatial scales in support of current irrigation technologies: the individual sprinkler (˜102m2) for variable rate irrigation, the individual wedge (˜103m2) for variable speed irrigation, and the quarter section (0.82 km2) for uniform rate irrigation. Additionally, we were able to generate a daily soil moisture product over the entire study area at various key modeling and remote sensing scales 12, 32, and 122 km2. Our soil moisture products and derived soil properties were then compared against spatial datasets (i.e. field capacity and wilting point) from the US Department of Agriculture Web Soil Survey. The results show that our "observed" field capacity was higher compared to the Web Soil Survey products. We hypothesize that our results, when provided to irrigators, will decrease water losses due to runoff and deep percolation as sprinkler managers can better estimate irrigation application depth and times in relation to soil moisture depletion below field capacity and above maximum allowable depletion. The incorporation of this non-contact and pragmatic geophysical method into current irrigation practices across the state and globe has the

  10. Decision Support System for an efficient irrigation water management in semi arid environment

    NASA Astrophysics Data System (ADS)

    Khan, M. A.; Islam, M.; Hafeez, M. M.; Flugel, W. A.

    2009-12-01

    A significant increase in agricultural productivity over the last few decades has protected the world from episodes of hunger and food shortages. Water management in irrigated agriculture was instrumental in achieving those gains. Water resources are under high pressure due to rapid population growth and increased competition among various sectors. Access to reliable data on water availability, quantity and quality can provide the necessary foundation for sound management of water resources. There are many traditional methods for matching water demand and supply, however imbalances between demand and supply remain inevitable. It is possible to reduce the imbalances considerably through development of appropriate irrigation water management tool that take into account various factors such as soil type, irrigation water supply, and crop water demand. All components of water balance need to be understood and quantified for efficient and sustainable management of water resources. Application of an intelligent Decision Support System (DSS) is becoming significant. A DSS incorporates knowledge and expertise within the decision support framework. It is an integrated set of data, functions, models and other relevant information that efficiently processes input data, simulates models and displays the results in a user friendly format. It helps in decision-making process, to analyse the problem and explore various scenarios to make the most appropriate decision for water management. This paper deals with the Coleambally Irrigation Area (CIA) located in Murrumbidgee catchment, NSW, Australia. An Integrated River Information System called Coleambally IRIS has been developed to improve the irrigation water management ranging from farm to sub-system and system level. It is a web-based information management system with a focus on time series and geospatial hydrological, climatic and remote sensing data including land cover class, surface temperature, soil moisture, Normalized

  11. Ground-water quality beneath irrigated agriculture in the central High Plains aquifer, 1999-2000

    USGS Publications Warehouse

    Bruce, Breton W.; Becker, Mark F.; Pope, Larry M.; Gurdak, Jason J.

    2003-01-01

    In 1999 and 2000, 30 water-quality monitoring wells were installed in the central High Plains aquifer to evaluate the quality of recently recharged ground water in areas of irrigated agriculture and to identify the factors affecting ground-water quality. Wells were installed adjacent to irrigated agricultural fields with 10- or 20-foot screened intervals placed near the water table. Each well was sampled once for about 100 waterquality constituents associated with agricultural practices. Water samples from 70 percent of the wells (21 of 30 sites) contained nitrate concentrations larger than expected background concentrations (about 3 mg/L as N) and detectable pesticides. Atrazine or its metabolite, deethylatrazine, were detected with greater frequency than other pesticides and were present in all 21 samples where pesticides were detected. The 21 samples with detectable pesticides also contained tritium concentrations large enough to indicate that at least some part of the water sample had been recharged within about the last 50 years. These 21 ground-water samples are considered to show water-quality effects related to irrigated agriculture. The remaining 9 groundwater samples contained no pesticides, small tritium concentrations, and nitrate concentrations less than 3.45 milligrams per liter as nitrogen. These samples are considered unaffected by the irrigated agricultural land-use setting. Nitrogen isotope ratios indicate that commercial fertilizer was the dominant source of nitrate in 13 of the 21 samples affected by irrigated agriculture. Nitrogen isotope ratios for 4 of these 21 samples were indicative of an animal waste source. Dissolved-solids concentrations were larger in samples affected by irrigated agriculture, with large sulfate concentrations having strong correlation with large dissolved solids concentrations in these samples. A strong statistical correlation is shown between samples affected by irrigated agriculture and sites with large rates of

  12. Modeling the effects of different irrigation water salinity on soil water movement, uptake and multicomponent solute transport

    NASA Astrophysics Data System (ADS)

    Lekakis, E. H.; Antonopoulos, V. Z.

    2015-11-01

    Simulation models can be important tools for analyzing and managing irrigation, soil salinization or crop production problems. In this study a mathematical model that describes the water movement and mass transport of individual ions (Ca2+, Mg2+ and Na+) and overall soil salinity by means of the soil solution electrical conductivity, is used. The mass transport equations of Ca2+, Mg2+ and Na+ have been incorporated as part of the integrated model WANISIM and the soil salinity was computed as the sum of individual ions. The model was calibrated and validated against field data, collected during a three year experiment in plots of maize, irrigated with three different irrigation water qualities, at Thessaloniki area in Northern Greece. The model was also used to evaluate salinization and sodification hazards by the use of irrigation water with increasing electrical conductivity of 0.8, 3.2 and 6.4 dS m-1, while maintaining a ratio of Ca2+:Mg2+:Na+ equal to 3:3:2. The qualitative and quantitative procedures for results evaluation showed that there was good agreement between the simulated and measured values of the water content, overall salinity and the concentration of individual soluble cations, at two soil layers (0-35 and 35-75 cm). Nutrient uptake was also taken into account. Locally available irrigation water (ECiw = 0.8 dS m-1) did not cause soil salinization or sodification. On the other hand, irrigation water with ECiw equal to 3.2 and 6.4 dS m-1 caused severe soil salinization, but not sodification. The rainfall water during the winter seasons was not sufficient to leach salts below the soil profile of 110 cm. The modified version of model WANISIM is able to predict the effects of irrigation with saline waters on soil and plant growth and it is suitable for irrigation management in areas with scarce and low quality water resources.

  13. Water savings potentials of irrigation systems: global simulation of processes and linkages

    NASA Astrophysics Data System (ADS)

    Jägermeyr, J.; Gerten, D.; Heinke, J.; Schaphoff, S.; Kummu, M.; Lucht, W.

    2015-07-01

    Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatiotemporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of global agricultural water use, and of water saving and water productivity potentials constrained by biophysical processes and also non-trivial downstream effects, we incorporated a process-based representation of the three major irrigation systems (surface, sprinkler, and drip) into a bio- and agrosphere model, LPJmL. Based on this enhanced model we provide a gridded world map of irrigation efficiencies that are calculated in direct linkage to differences in system types, crop types, climatic and hydrologic conditions, and overall crop management. We find pronounced regional patterns in beneficial irrigation efficiency (a refined irrigation efficiency indicator accounting for crop-productive water consumption only), due to differences in these features, with the lowest values (< 30 %) in south Asia and sub-Saharan Africa and the highest values (> 60 %) in Europe and North America. We arrive at an estimate of global irrigation water withdrawal of 2469 km3 (2004-2009 average); irrigation water consumption is calculated to be 1257 km3, of which 608 km3 are non-beneficially consumed, i.e., lost through evaporation, interception, and conveyance. Replacing surface systems by sprinkler or drip systems could, on average across the world's river basins, reduce the non-beneficial consumption at river basin level by 54 and 76 %, respectively, while maintaining the current level of crop yields. Accordingly, crop water productivity would increase by 9 and 15 %, respectively, and by much more in specific regions such as in the Indus basin. This study significantly advances the global

  14. Stover removal and cover crops effects on corn production and water use under full and limited irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L.) residue removal in irrigated cropping systems for livestock forage or cellulosic ethanol is of great interest in south-central Nebraska. Irrigation water restrictions in the region have also resulted in adoption of limited-irrigation strategies. Little is known regarding the inter...

  15. Integrating irrigation water demand, supply, and delivery management in a stochastic environment

    NASA Astrophysics Data System (ADS)

    Dudley, Norman J.; Scott, Bradley W.

    1993-09-01

    Previously developed suites of models integrate irrigation water supply and demand management for simplified surface reservoir supply systems. A central stochastic dynamic programming model is supported by simulation models, including a soil water-plant growth model. That modeling is extended herein to include decisions about timing and quantity of reservoir water releases into the delivery system, resulting in the integration of supply, demand, and delivery management. Irrigators have rights to percentages of reservoir capacity, reservoir inflows, and downstream tributary flows. Natural rivers are the supply channels in the study area. Large on-farm water storages exist for storing regulated and unregulated river flows available to the irrigators. Farms can be many days flow from the reservoir, requiring orders for reservoir releases to be lodged before the arrival of a previous order. The probability of unregulated flows from tributaries downstream of the reservoir further complicates ordering decisions. Abandonment of irrigated area to rain-fed status occurs at two levels, forced abandonment if insufficient water is available at the farm when the irrigation-trigger soil water deficit is reached, and planned abandonment to save water for possible later use. The need for forced abandonment is determined by simulation models; planned abandonment decisions are derived by stochastic dynamic programming. Results show annual net revenue means and standard deviations as functions of different capacities of the on-farm storages and water supplies from either regulated or unregulated flows, or both.

  16. Purification of contaminated paddy fields by clean water irrigation over two decades.

    PubMed

    Tai, Yiping; Lu, Huanping; Li, Zhian; Zhuang, Ping; Zou, Bi; Xia, Hanping; Wang, Faming; Wang, Gang; Duan, Jun; Zhang, Jianxia

    2013-10-01

    Paddy fields near a mining site in north part of Guangdong Province, PR China, were severely contaminated by heavy metals as a result of wastewater irrigation from the tailing pond. The following clean water irrigation for 2 decades produced marked rinsing effect, especially on Pb and Zn. Paddy fields continuously irrigated with wastewater ever since mining started (50 years) had 1,050.0 mg kg−1 of Pb and 810.3 mg kg−1 of Zn for upper 20 cm soil, in comparison with 215.9 mg kg−1 of Pb and 525.4 mg kg−1 of Zn, respectively, with clean water irrigation for 20 years. Rinsing effect mainly occurred to a depth of upper 40 cm, of which the soil contained highest metals. Copper and Cd in the farmlands were also reduced due to clean water irrigation. Higher availability of Pb might partly account for more Pb transferred from the tailing pond to the farmland and also more Pb removal from the farmland as a result of clean water irrigation. Neither rice in the paddy field nor dense weeds in the uncultivated field largely took up the metals. However, they might contribute to activate metals differently, leading to a different purification extent. Rotation of rice and weed reduced metal retention in the farmland soil, in comparison with sole rice growth. Harvesting of rice grain (and partially rice stalk) only contributed small fraction of total amount of removed metal. In summary, heavy metal in paddy field resulting from irrigation of mining wastewater could be largely removed by clean water irrigation for sufficient time. PMID:23797601

  17. Crop-specific seasonal estimates of irrigation-water demand in South Asia

    NASA Astrophysics Data System (ADS)

    Biemans, Hester; Siderius, Christian; Mishra, Ashok; Ahmad, Bashir

    2016-05-01

    Especially in the Himalayan headwaters of the main rivers in South Asia, shifts in runoff are expected as a result of a rapidly changing climate. In recent years, our insight into these shifts and their impact on water availability has increased. However, a similar detailed understanding of the seasonal pattern in water demand is surprisingly absent. This hampers a proper assessment of water stress and ways to cope and adapt. In this study, the seasonal pattern of irrigation-water demand resulting from the typical practice of multiple cropping in South Asia was accounted for by introducing double cropping with monsoon-dependent planting dates in a hydrology and vegetation model. Crop yields were calibrated to the latest state-level statistics of India, Pakistan, Bangladesh and Nepal. The improvements in seasonal land use and cropping periods lead to lower estimates of irrigation-water demand compared to previous model-based studies, despite the net irrigated area being higher. Crop irrigation-water demand differs sharply between seasons and regions; in Pakistan, winter (rabi) and monsoon summer (kharif) irrigation demands are almost equal, whereas in Bangladesh the rabi demand is ~ 100 times higher. Moreover, the relative importance of irrigation supply versus rain decreases sharply from west to east. Given the size and importance of South Asia improved regional estimates of food production and its irrigation-water demand will also affect global estimates. In models used for global water resources and food-security assessments, processes like multiple cropping and monsoon-dependent planting dates should not be ignored.

  18. Crop-specific seasonal estimates of irrigation water demand in South Asia

    NASA Astrophysics Data System (ADS)

    Biemans, H.; Siderius, C.; Mishra, A.; Ahmad, B.

    2015-08-01

    Especially in the Himalayan headwaters of the main rivers in South Asia, shifts in runoff are expected as a result of a rapidly changing climate. In recent years, our insight in these shifts and their impact on water availability has increased. However, a similar detailed understanding of the seasonal pattern in water demand is surprisingly absent. This hampers a proper assessment of water stress and ways to cope and adapt. In this study, the seasonal pattern of irrigation water demand resulting from the typical practice of multiple-cropping in South Asia was accounted for by introducing double-cropping with monsoon-dependent planting dates in a hydrology and vegetation model. Crop yields were calibrated to the latest subnational statistics of India, Pakistan, Bangladesh and Nepal. The representation of seasonal land use and more accurate cropping periods lead to lower estimates of irrigation water demand compared to previous model-based studies, despite the net irrigated area being higher. Crop irrigation water demand differs sharply between seasons and regions; in Pakistan, winter (Rabi) and summer (Kharif) irrigation demands are almost equal, whereas in Bangladesh the Rabi demand is ~ 100 times higher. Moreover, the relative importance of irrigation supply vs. rain decreases sharply from west to east. Given the size and importance of South Asia, improved regional estimates of food production and its irrigation water demand will also affect global estimates. In models used for global water resources and food-security assessments, processes like multiple-cropping and monsoon-dependent planting dates should not be ignored.

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

    NASA Astrophysics Data System (ADS)

    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

  20. Faecal contamination indicators, Salmonella, Vibrio and Aeromonas in water used for the irrigation of agricultural products.

    PubMed Central

    Pianietti, A.; Sabatini, L.; Bruscolini, F.; Chiaverini, F.; Cecchetti, G.

    2004-01-01

    The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21.6% of the strains were adhesive and 12.6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers. PMID:15061497

  1. TECHNICAL CONCEPTS RELATED TO CONSERVATION OF IRRIGATION AND RAIN WATER IN AGRICULTURAL SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forty percent of freshwater withdrawals in the U.S. are for irrigated agriculture, which contributed 55$ billion to the economy in 2002. Increasing diversions of water for urban, environmental, and other uses will likely decrease water available to agriculture. Agricultural water conservation is tou...

  2. Simulations of Limited-Water Irrigation Management Options for Corn in Dryland Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diminishing land and water resources due to increasing demands from rapid population growth calls for increasing water use efficiency of irrigated crops. To produce more for every drop of water used in agriculture, it is important to develop location specific alternate agronomic practices vis-à-vis...

  3. Optimizing Irrigation Water Allocation under Multiple Sources of Uncertainty in an Arid River Basin

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Tang, D.; Gao, H.; Ding, Y.

    2015-12-01

    Population growth and climate change add additional pressures affecting water resources management strategies for meeting demands from different economic sectors. It is especially challenging in arid regions where fresh water is limited. For instance, in the Tailanhe River Basin (Xinjiang, China), a compromise must be made between water suppliers and users during drought years. This study presents a multi-objective irrigation water allocation model to cope with water scarcity in arid river basins. To deal with the uncertainties from multiple sources in the water allocation system (e.g., variations of available water amount, crop yield, crop prices, and water price), the model employs a interval linear programming approach. The multi-objective optimization model developed from this study is characterized by integrating eco-system service theory into water-saving measures. For evaluation purposes, the model is used to construct an optimal allocation system for irrigation areas fed by the Tailan River (Xinjiang Province, China). The objective functions to be optimized are formulated based on these irrigation areas' economic, social, and ecological benefits. The optimal irrigation water allocation plans are made under different hydroclimate conditions (wet year, normal year, and dry year), with multiple sources of uncertainty represented. The modeling tool and results are valuable for advising decision making by the local water authority—and the agricultural community—especially on measures for coping with water scarcity (by incorporating uncertain factors associated with crop production planning).

  4. Irrigation scheduling as affected by field capacity and wilting point water content from different data sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil water content at field capacity and wilting point water content is critical information for irrigation scheduling, regardless of soil water sensor-based method (SM) or evapotranspiration (ET)-based method. Both methods require knowledge on site-specific and soil-specific Management Allowable De...

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

    NASA Astrophysics Data System (ADS)

    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

  6. Normal water irrigation as an alternative to effluent irrigation in improving rice grain yield and properties of a paper mill effluent affected soil.

    PubMed

    Boruah, D; Hazarika, S

    2010-07-01

    Rice crop (var. Luit) was grown under controlled conditions in paper mill effluent contaminated soil and irrigated with undiluted paper mill effluent as well as normal water and compared the results against a control treatment consisting of similar unaffected soil irrigated with normal water. The effluent was alkaline (pH 7.5), containing high soluble salts (EC 2.93 dS m(-1)), chloride (600 mg L(-1)) and total dissolved solids (1875 mg L(-1)). At maximum tillering (MT) stage effluent irrigation significantly (P < 0.05) reduced the leaf numbers per hill and leaf area by 19.8 and 36.4 %, respectively. Tiller number and maximum root length were reduced by 19.3% and 12.5%, respectively at fifty percent flowering (FF) stage. Effluent irrigated crop recorded significant reduction in the dry matter production (17.5-24.9%) and grain yield (19%). Unfilled grain was increased by 10.7%. Higher concentration of sodium, calcium and magnesium in the effluent irrigated soil affected K uptake. Available soil P was lowest while available N, K, S and exchangeable and water soluble Na, K, Ca, Mg were highest in effluent irrigated soil. Chloride content found to increase (3-7 folds) while microbial biomass carbon reduced (10-37%). The adverse effect of the paper mill effluent on the crop as well as on the affected soil could be reduced significantly through normal water irrigation. PMID:21391395

  7. Effect of timing of a deficit-irrigation allocation on corn evapotranspiration, yield, water use efficiency and dry mass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water regulations have decreased irrigation water supplies in Nebraska and some other areas of the USA Great Plains. When available water is not enough to meet crop water requirements during the entire growing cycle, it becomes critical to know the proper irrigation timing that would maximize yield...

  8. Irrigated Agriculture and Water Resources in the Western U.S. (Invited)

    NASA Astrophysics Data System (ADS)

    Trout, T. J.

    2013-12-01

    Agriculture in semi-arid areas such as the western U.S. was created by diverting and pumping water from rivers and groundwater. With that water, highly productive irrigated agriculture produces 40% of the crop value and the large majority of the fruits, vegetables, and nuts in the U.S. Irrigation water use and area is declining in the West, due both to overexploitation and increasing competing needs, although productivity continues to increase. The challenges for irrigated agriculture are to maximize productivity per unit of water consumed, minimize negative environmental impacts, and make water available to other needs while sustaining food production and rural economies. Meeting these challenges require both technical and policy advances.

  9. Water and nitrogen requirements of subsurface drip irrigated pomegranate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. Three novel phytophthora species from irrigation water in Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Phytophthora includes a number of destructive plant pathogens. Here we report three new taxa recovered from irrigation systems at an ornamental crop nursery in Mississippi. Isolates of these new taxa were recovered from rhododendron leaves submerged in ponds for 7 days in 2012. Isolat...

  11. A genetic approach to producing rice using less irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research has shown that conventional rice production using the permanent flooded system can also result in high methane emissions, increased grain arsenic accumulation, and extensive demand on irrigation resources. Although rice is a staple grain for feeding half the world, there has been increasin...

  12. A case study of a bacterial pathogen in irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter presents a case study of how exotic strains of Ralstonia solanacearum were disseminated throughout Europe and Florida via waterways used for irrigation. Several studies have demonstrated that aquatic weeds that commonly grow in rivers and ponds are able to harbor the pathogen and allow ...

  13. Safety assessment of greenhouse hydroponic tomatoes irrigated with reclaimed and surface water.

    PubMed

    Lopez-Galvez, Francisco; Allende, Ana; Pedrero-Salcedo, Francisco; Alarcon, Juan Jose; Gil, Maria Isabel

    2014-11-17

    The impact of reclaimed and surface water on the microbiological safety of hydroponic tomatoes was assessed. Greenhouse tomatoes were irrigated with reclaimed and surface water and grown on two hydroponic substrates (coconut fiber and rock wool). Water samples (n=208) were taken from irrigation water, with and without the addition of fertilizers and drainage water, and hydroponic tomatoes (n=72). Samples were analyzed for indicator microorganisms, generic Escherichia coli and Listeria spp., and pathogenic bacteria such as Salmonella spp. and Shiga-toxigenic E. coli (STEC), using multiplex real-time PCR (RT-PCR) after enrichment. The correlation between climatological parameters such as temperature and the levels of microorganisms in water samples was also determined. In irrigation water, generic E. coli counts were higher in reclaimed than in surface water whereas Listeria spp. numbers increased after adding the fertilizers in both water sources. In drainage water, no clear differences in E. coli and Listeria numbers were observed between reclaimed and surface water. No positive samples for STEC were found in irrigation water. Presumptive positives for Salmonella spp. were found in 7.7% of the water samples and 62.5% of these samples were reclaimed water. Salmonella-positive samples by RT-PCR could not be confirmed by conventional methods. Higher concentrations of E. coli were associated with Salmonella-presumptive positive samples. Climatological parameters, such as temperature, were not correlated with the E. coli and Listeria spp. counts. Tomato samples were negative for bacterial pathogens, while generic E. coli and Listeria spp. counts were below the detection limit. The prevalence of presumptive Salmonella spp. found in irrigation water (reclaimed and surface water) was high, which might present a risk of contamination. The absence of pathogens on greenhouse hydroponic tomatoes indicates that good agricultural practices (GAP) were in place, avoiding the

  14. Spatial regression between soil surface elevation, water storage in root zone and biomass productivity of alfalfa within an irrigated field

    NASA Astrophysics Data System (ADS)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2014-05-01

    Efficiency of water use for the irrigation purposes is connected to the variety of circumstances, factors and processes appearing along the transportation path of water from its sources to the root zone of the plant. Water efficiency of agricultural irrigation is connected with variety of circumstances, the impacts and the processes occurring during the transportation of water from water sources to plant root zone. Agrohydrological processes occur directly at the irrigated field, these processes linked to the infiltration of the applied water subsequent redistribution of the infiltrated water within the root zone. One of them are agrohydrological processes occurring directly on an irrigated field, connected with infiltration of water applied for irrigation to the soil, and the subsequent redistribution of infiltrated water in the root zone. These processes have the strongly pronounced spatial character depending on the one hand from a spatial variation of some hydrological characteristics of soils, and from other hand with distribution of volume of irrigation water on a surface of the area of an irrigated field closely linked with irrigation technology used. The combination of water application parameters with agrohydrological characteristics of soils and agricultural vegetation in each point at the surface of an irrigated field leads to formation of a vector field of intensity of irrigation water. In an ideal situation, such velocity field on a soil surface should represent uniform set of vertically directed collinear vectors. Thus values of these vectors should be equal to infiltration intensities of water inflows on a soil surface. In soil profile the field of formed intensities of a water flow should lead to formation in it of a water storage accessible to root system of irrigated crops. In practice this ideal scheme undergoes a lot of changes. These changes have the different nature, the reasons of occurrence and degree of influence on the processes connected

  15. A modeling study of irrigation effects on global surface water and groundwater resources under a changing climate

    NASA Astrophysics Data System (ADS)

    Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Leung, L. Ruby

    2015-09-01

    This study investigates the effects of irrigation on global water resources by performing and analyzing Community Land Model 4.0 (CLM4) simulations driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs). For each climate scenario, three sets of numerical experiments were performed: (1) a CTRL experiment in which all crops are assumed to be rainfed; (2) an IRRIG experiment in which the irrigation module is activated using surface water (SW) to feed irrigation; and (3) a PUMP experiment in which a groundwater pumping scheme coupled with the irrigation module is activated for conjunctive use of surface water and groundwater (GW) for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based water use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major effects: SW (GW) depletion in regions with irrigation primarily fed by SW (GW), respectively. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting increased vulnerability to drought. By the end of the 21st century, combined effect of increased irrigation water demand and amplified temporal-spatial variability of water supply may lead to severe local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our study highlights the need to account for irrigation effects and sources in assessing regional climate change impacts.

  16. Presence and distribution of wastewater-derived pharmaceuticals in soil irrigated with reclaimed water

    USGS Publications Warehouse

    Kinney, C.A.; Furlong, E.T.; Werner, S.L.; Cahill, J.D.

    2006-01-01

    Three sites in the Front Range of Colorado, USA, were monitored from May through September 2003 to assess the presence and distribution of pharmaceuticals in soil irrigated with reclaimed water derived from urban wastewater. Soil cores were collected monthly, and 19 pharmaceuticals, all of which were detected during the present study, were measured in 5-cm increments of the 30-cm cores. Samples of reclaimed water were analyzed three times during the study to assess the input of pharmaceuticals. Samples collected before the onset of irrigation in 2003 contained numerous pharmaceuticals, likely resulting from the previous year's irrigation. Several of the selected pharmaceuticals increased in total soil concentration at one or more of the sites. The four most commonly detected pharmaceuticals were erythromycin, carbamazepine, fluoxetine, and diphenhydramine. Typical concentrations of the individual pharmaceuticals observed were low (0.02-15 ??g/kg dry soil). The existence of subsurface maximum concentrations and detectable concentrations at the lowest sampled soil depth might indicate interactions of soil components with pharmaceuticals during leaching through the vadose zone. Nevertheless, the present study demonstrates that reclaimed-water irrigation results in soil pharmaceutical concentrations that vary through the irrigation season and that some compounds persist for months after irrigation. ?? 2006 SETAC.

  17. A site-specific agricultural water requirement and footprint estimator (SPARE:WATER 1.0) for irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.

    2013-01-01

    The water footprint accounting method addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). Most of current water footprint assessments focus on global to continental scale. We therefore developed the spatial decision support system SPARE:WATER that allows to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirement and water footprints are assessed on a grid-basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume in-efficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water can be defined as the water to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008 with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional water footprint assessments.

  18. [Effects of different irrigations on the water physiological characteristics of Haloxylon ammodendron in Taklimakan Desert hinterland].

    PubMed

    Xie, Ting-ting; Zhang, Xi-ming; Liang, Shao-min; Shan, Li-shan; Yang, Xiao-lin; Hua, Yong-hui

    2008-04-01

    By using heat-balance stem flow gauge and press chamber, the water physiological characteristics of Haloxylon ammodendron under different irrigations in Taklimakan Desert hinterland were measured and analyzed. The results indicated that the diurnal variation curve of H. ammodendron stem sap flow varied with irrigations. When irrigated 35 and 24.5 kg x plant(-1) once time, the diurnal variation of stem sap flow changed in single peak curve and the variation extent was higher; while irrigated 14 kg x plant(-1) once time, the diurnal variation changed in two-peak curve and the variation extent was small. With the decrease of irrigations, the average daily sap flow rate and the daily water consumption of H. ammodendron decreased gradually, the dawn and postmeridian water potential also had a gradual decrease, and the correlations of stem sap flow with total radiation, air temperature, relative humidity, and wind speed enhanced. Under different irrigations, the correlation between stem sap flow rate and total radiation was always the best. PMID:18593026

  19. Estimated demand for agricultural water for irrigation use in New Jersey, 1990

    USGS Publications Warehouse

    Titus, E.O.; Clawges, R.M.; Qualls, C.L.

    1990-01-01

    As part of an effort to determine if an adequate supply of agricultural water for irrigation use will be available to farmers, the U.S. Geological Survey prepared preliminary estimates of demand for agricultural water for irrigation use for the year 1990 on the basis of six possible scenarios. These scenarios incorporate normal and drought climatic conditions and three alternative estimates of the total acreage of farmland that may be irrigated in 1990. Preliminary estimates of water demand based on soil-moisture deficits were made using methods for calculating climatic water budgets. These estimates ranged from 3.0 billion gal/growing season (May through September), under normal climatic conditions and a 2% annual decline in irrigated acreage since 1984, to 28. 9 billion gal/growing season, under drought conditions and a 2% annual increase in irrigated acreage since 1984. Preliminary estimates of water demand made for the 1986 growing season reasonably approximate reported water use for that period. (USGS)

  20. Irrigation experiments with produced waters from the retorting of oil shale

    SciTech Connect

    Hutchinson, D.L.

    1980-12-01

    The research described herein was conducted by Geokinetics to qualitatively assess the tolerance of native and certain introduced species of vegetation to irrigation with produced water from the retorting of oil shale. Two separate experiments were conducted at the Kamp Kerogen field site in Uintah County, Utah. The results indicate possible effects on vegetation that a prolonged exposure to produced water would have. The two simple experiments were initiated during the summer of 1979. It was expected that irrigation with produced water would eventually result in detrimental effects to the plants receiving it; the concentrations of boron, molybdenum, arsenic, oil and other constituents in untreated production waters are high enough to likely cause damage to plants. In one experiment a 27 foot by 27 foot plot of native vegetation was irrigated with one inch of produced water per week for five weeks using a lawn sprinkler. Grasses and shrubs within the test plot appeared to have died; germination of annual plants was greatly inhibited. In the other experiment, 30 container-grown seedlings ranging in height from 0.3 feet to 3.0 feet were transplanted. Six species of broadleaf, deciduous trees not native to the test site were represented by five seedlings each. All 30 trees received well water irrigation for one month, after which four trees of each species were irrigated with produced water for seven weeks. One tree of each species continued to receive well water throughout the experiment; only two of those trees survived the summer of 1979. All six species appeared to have been adversely affected by produced water. The horse chesnut trees were the hardiest of the species planted. Most of the 30 trees, including those irrigated with well water, did not survive the winter season.

  1. [Impact of reclaimed water irrigation on soil chemical properties and culturable microorganisms ].

    PubMed

    Gong, Xue; Wang, Ji-hua; Guan, Jian-fei; Yang, Xue-chen; Chen, Dai-ci

    2014-09-01

    This research used batch soil column experiment to study the effects of irrigating with reclaimed water and tap water on the soil chemical properties and culturable microorganisms. The results indicated that reclaimed water could markedly increase the soil organic material (OM) and total nitrogen (TN) content, but it had no obvious effect on total phosphorus (TP), available phosphorus (AP) and pH value. Reclaimed water irrigation could significantly enhance the amounts of surface soil bacteria and actinomycetes at a depth of 0-20 cm, but it had little effect on the biomass of 20-40 cm and 40-60 cm soil layers. The dominant bacteria in tap water irrigation area was the genus Bacillus whereas that of reclaimed water irrigation area was the genus Acinetobacter. Tap water irrigation area had four endemic genera and reclaimed water irrigation area had six endemic genera. Reclaimed water had no obvious effect on the microbial community Shannon diversity of 0-20 cm soil layer, while it decreased Pielou evenness index, and improved Margalef richness index. Through SPSS 17. 0 correlation analysis between soil microbes quantity and soil chemical properties, it was shown that the soil microbes quantity was positively correlated with OM, TN, TP and AP, but negatively correlated with soil water content (SWC) and pH value. Based on CANOCO 4.5 detrended correspondence analysis (DCA) and redundancy analysis (RDA) between soil microbes species and soil chemical properties, it was shown that AP had the strongest correlation with the microbial community (P = 0.002). TN and TP had larger impact on Streptococcus, Aeromonas and Neisseria. OM and AP had larger impact on Aerococcus, Planococcus and Halobacterium. PMID:25518681

  2. Water and energy footprint of irrigated agriculture in the Mediterranean region

    NASA Astrophysics Data System (ADS)

    Daccache, A.; Ciurana, J. S.; Rodriguez Diaz, J. A.; Knox, J. W.

    2014-12-01

    Irrigated agriculture constitutes the largest consumer of freshwater in the Mediterranean region and provides a major source of income and employment for rural livelihoods. However, increasing droughts and water scarcity have highlighted concerns regarding the environmental sustainability of agriculture in the region. An integrated assessment combining a gridded water balance model with a geodatabase and GIS has been developed and used to assess the water demand and energy footprint of irrigated production in the region. Modelled outputs were linked with crop yield and water resources data to estimate water (m3 kg-1) and energy (CO2 kg-1) productivity and identify vulnerable areas or ‘hotspots’. For a selected key crops in the region, irrigation accounts for 61 km3 yr-1 of water abstraction and 1.78 Gt CO2 emissions yr-1, with most emissions from sunflower (73 kg CO2/t) and cotton (60 kg CO2/t) production. Wheat is a major strategic crop in the region and was estimated to have a water productivity of 1000 t Mm-3 and emissions of 31 kg CO2/t. Irrigation modernization would save around 8 km3 of water but would correspondingly increase CO2 emissions by around +135%. Shifting from rain-fed to irrigated production would increase irrigation demand to 166 km3 yr-1 (+137%) whilst CO2 emissions would rise by +270%. The study has major policy implications for understanding the water-energy-food nexus in the region and the trade-offs between strategies to save water, reduce CO2 emissions and/or intensify food production.

  3. Use of Moringa oleifera seed extracts to reduce helminth egg numbers and turbidity in irrigation water.

    PubMed

    Sengupta, Mita E; Keraita, Bernard; Olsen, Annette; Boateng, Osei K; Thamsborg, Stig M; Pálsdóttir, Guðný R; Dalsgaard, Anders

    2012-07-01

    Water from wastewater-polluted streams and dug-outs is the most commonly used water source for irrigation in urban farming in Ghana, but helminth parasite eggs in the water represent health risks when used for crop production. Conventional water treatment is expensive, requires advanced technology and often breaks down in less developed countries so low cost interventions are needed. Field and laboratory based trials were carried out in order to investigate the effect of the natural coagulant Moringa oleifera (MO) seed extracts in reducing helminh eggs and turbidity in irrigation water, turbid water, wastewater and tap water. In medium to high turbid water MO extracts were effective in reducing the number of helminth eggs by 94-99.5% to 1-2 eggs per litre and the turbidity to 7-11 NTU which is an 85-96% reduction. MO is readily available in many tropical countries and can be used by farmers to treat high turbid water for irrigation, however, additional improvements of water quality, e.g. by sand filtration, is suggested to meet the guideline value of ≤ 1 helminth egg per litre and a turbidity of ≤ 2 NTU as recommended by the World Health Organization and the U.S. Environmental Protection Agency for water intended for irrigation. A positive correlation was established between reduction in turbidity and helminth eggs in irrigation water, turbid water and wastewater treated with MO. This indicates that helminth eggs attach to suspended particles and/or flocs facilitated by MO in the water, and that turbidity and helminth eggs are reduced with the settling flocs. However, more experiments with water samples containing naturally occurring helminth eggs are needed to establish whether turbidity can be used as a proxy for helminth eggs. PMID:22546609

  4. Irrigation with treated wastewater: effects on soil, lettuce (Lactuca sativa L.) crop and dynamics of microorganisms.

    PubMed

    Mañas, Pilar; Castro, Elena; de Las Heras, Jorge

    2009-10-01

    The aim of this study was to evaluate the applicability of treated wastewater for horticultural crops, assess the effects of continuous use of treated water on soil and crops, and analyse the physical, chemical and biological effects of irrigation with recycled water. Two lettuce plots watered with drinking water and treated wastewater were monitored over a three year period. Nutrients, heavy metal and the dynamics of pathogen and indicator microorganism content in soil and foliar tissues were analysed. Wastewater irrigation had a high influence on soil parameters: organic matter, N, P, Ca, Al, Fe, Pb and Zn. Indicator and pathogenic microorganisms were detected in soil and plants grown in the wastewater-irrigated plot, and persisted in the soil for 27 days during the study under humid conditions. N, P, Pb and Al content were significantly higher in plant tissues of wastewater-irrigated plots than in the control after 3 years of irrigation. Harvest was significantly higher in the wastewater-irrigated plot. Wastewater can be a resource for agricultural irrigation. In any case, the possible heavy metal accumulation in soils and presence of pathogenic organisms require careful management of this alternative resource: use of a drip irrigation system, previous wastewater disinfection and a limited irrigation period are recommended. PMID:19847714

  5. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Can I receive irrigation water if I am granted an Annual Assessment Waiver? 171.710 Section 171.710 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an...

  6. Cultivar Mixture Cropping Increased Water Use Efficiency in Winter Wheat under Limited Irrigation Conditions

    PubMed Central

    Wang, Yunqi; Zhang, Yinghua; Ji, Wei; Yu, Peng; Wang, Bin; Li, Jinpeng; Han, Meikun; Xu, Xuexin; Wang, Zhimin

    2016-01-01

    The effects of cultivar mixture cropping on yield, biomass, and water use efficiency (WUE) in winter wheat (Triticum aestivum L.) were investigated under non-irrigation (W0, no irrigation during growth stage), one time irrigation (W1, irrigation applied at stem elongation) and two times irrigation (W2, irrigation applied at stem elongation and anthesis) conditions. Nearly 90% of cultivar mixture cropping treatments experienced an increase in grain yield as compared with the mean of the pure stands under W0, those for W1 and W2 were 80% and 85%, respectively. Over 75% of cultivar mixture cropping treatments got greater biomass than the mean of the pure stands under the three irrigation conditions. Cultivar mixture cropping cost more water than pure stands under W0 and W1, whereas the water consumption under W2 decreased by 5.9%–6.8% as compared with pure stands. Approximately 90% of cultivar mixtures showed an increase of 5.4%–34.5% in WUE as compared with the mean of the pure stands, and about 75% of cultivar mixtures had 0.8%–28.5% higher WUE than the better pure stands under W0. Similarly, there were a majority of mixture cropping treatments with higher WUE than the mean and the better one of the pure stands under W1 and W2. On the whole, proper cultivar mixture cropping could increase yield and WUE, and a higher increase in WUE occurred under limited irrigation condition. PMID:27362563

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

    NASA Astrophysics Data System (ADS)

    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

  8. Classifying Residents who use Landscape Irrigation: Implications for Encouraging Water Conservation Behavior.

    PubMed

    Warner, Laura A; Lamm, Alexa J; Rumble, Joy N; Martin, Emmett T; Cantrell, Randall

    2016-08-01

    Large amounts of water applied as urban irrigation can often be reduced substantially without compromising esthetics. Thus, encouraging the adoption of water-saving technologies and practices is critical to preserving water resources, yet difficult to achieve. The research problem addressed in this study is the lack of characterization of residents who use urban irrigation, which hinders the design of effective behavior change programs. This study examined audience segmentation as an approach to encouraging change using current residential landscape practices. K-means cluster analysis identified three meaningful subgroups among residential landscape irrigation users (N = 1,063): the water considerate majority (n = 479, 45 %), water savvy conservationists (n = 378, 36 %), and unconcerned water users (n = 201, 19 %). An important finding was that normative beliefs, attitudes, and perceived behavioral control characteristics of the subgroups were significantly different with large and medium practical effect sizes. Future water conservation behaviors and perceived importance of water resources were also significantly different among subgroups. The water considerate majority demonstrated capacity to conserve, placed high value on water, and were likely to engage in behavior changes. This article contributes to the literature on individuals who use residential landscape irrigation, an important target audience with potential to conserve water through sustainable irrigation practices and technologies. Findings confirm applicability of the capacity to conserve water to audience segmentation and extend this concept by incorporating perceived value of water resources and likelihood of conservation. The results suggest practical application to promoting residential landscape water conservation behaviors based on important audience characteristics. PMID:27177542

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

    PubMed

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

    2015-05-15

    Phytoextraction is an effective method to remediate heavy metal contaminated landscapes but is often applied for single metal contaminants. Plants used for phytoextraction may not always be able to grow in drier environments without irrigation. This study investigated if willows (Salix x reichardtii A. Kerner) can be used for phytoextraction of multiple metals in biosolids, an end-product of the wastewater treatment process, and if irrigation with reclaimed and freshwater influences the extraction process. A plantation of willows was established directly onto a tilled stockpile of metal-contaminated biosolids and irrigated with slightly saline reclaimed water (EC ∼2 dS/cm) at a wastewater processing plant in Victoria, Australia. Biomass was harvested annually and analysed for heavy metal content. Phytoextraction of cadmium, copper, nickel and zinc was benchmarked against freshwater irrigated willows. The minimum irrigation rate of 700 mm per growing season was sufficient for willows to grow and extract metals. Increasing irrigation rates produced no differences in total biomass and also no differences in the extraction of heavy metals. The reclaimed water reduced both the salinity and the acidity of the biosolids significantly within the first 12 months after irrigation commenced and after three seasons the salinity of the biosolids had dropped to <15% of initial values. A flushing treatment to remove excess salts was therefore not necessary. Irrigation had an impact on biosolids attributes such as salinity and pH, and that this had an influence on metal extraction. Reclaimed water irrigation reduced the biosolid pH and this was associated with reductions of the extraction of Ni and Zn, it did not influence the extraction of Cu and enhanced the phytoextraction of Cd, which was probably related to the high chloride content of the reclaimed water. Our results demonstrate that flood-irrigation with reclaimed water was a successful treatment to grow willows in a

  10. Age of irrigation water in ground water from the Eastern Snake River Plain Aquifer, south-central Idaho

    USGS Publications Warehouse

    Plummer, L.N.; Rupert, M.G.; Busenberg, E.; Schlosser, P.

    2000-01-01

    Stable isotope data (2H and 18O) were used in conjunction with chlorofluorocarbon (CFC) and tritium/helium-3 (3H/3He) data to determine the fraction and age of irrigation water in ground water mixtures from farmed parts of the Eastern Snake River Plain (ESRP) Aquifer in south-central Idaho. Two groups of waters were recognized: (1) regional background water, unaffected by irrigation and fertilizer application, and (2) mixtures of irrigation water from the Snake River with regional background water. New data are presented comparing CFC and 3H/3He dating of water recharged through deep fractured basalt, and dating of young fractions in ground water mixtures. The 3H/3He ages of irrigation water in most mixtures ranged from about zero to eight years. The CFC ages of irrigation water in mixtures ranged from values near those based on 3H/3He dating to values biased older than the 3H/3He ages by as much as eight to 10 years. Unsaturated zone air had CFC-12 and CFC-113 concentrations that were 60% to 95%, and 50% to 90%, respectively, of modern air concentrations and were consistently contaminated with CFC-11. Irrigation water diverted from the Snake River was contaminated with CFC-11 but near solubility equilibrium with CFC-12 and CFC-113. The dating indicates ground water velocities of 5 to 8 m/d for water along the top of the ESRP Aquifer near the southwestern boundary of the Idaho National Engineering and Environmental Laboratory (INEEL). Many of the regional background waters contain excess terrigenic helium with a 3He/4He isotope ratio of 7 x 10-6 to 11 x 10-6 (R/Ra = 5 to 8) and could not be dated. Ratios of CFC data indicate that some rangeland water may contain as much as 5% to 30% young water (ages of less than or equal to two to 11.5 years) mixed with old regional background water. The relatively low residence times of ground water in irrigated parts of the ESRP Aquifer and the dilution with low-NO3 irrigation water from the Snake River lower the potential for

  11. Produced water irrigation changes the soil mesofauna community in a semiarid agroecosystem.

    PubMed

    Ferreira, Raimundo Nonato Costa; Weber, Olmar Baller; Crisóstomo, Lindbergue Araujo

    2015-08-01

    The scarcity of water in semiarid regions requires alternative sources for irrigation to improve agricultural production. Here, we aimed to evaluate the effects of produced water from oil exploration on the structure of soil mesofauna during the dry and rainy seasons in irrigated sunflower and castor bean fields in a Brazilian semiarid region. Three irrigation treatments were applied on plots cultivated with castor beans and sunflowers: produced water treated by filtration (filtrated) or treated by reverse osmosis (reverse osmosis) and groundwater. The mesofauna under the biofuel crops was collected and identified during the dry and rainy seasons. Although the abundance and richness of the total fauna did not differ between seasons in sunflower plots, the community was altered. In castor beans, the abundance, richness, and community of mesofauna observed in plots irrigated with produced water differed from the groundwater treatment. Irrigation with produced water promotes important changes in soil fauna community that justify their assessment for the maintenance and monitoring of agroecosystems. PMID:26205282

  12. Management of Chronic Periodontitis Using Subgingival Irrigation of Ozonized Water: A Clinical and Microbiological Study

    PubMed Central

    Mathew, Jayan Jacob; Ambooken, Majo; Kachappilly, Arun Jose; PK, Ajithkumar; Johny, Thomas; VK, Linith; Samuel, Anju

    2015-01-01

    Introduction Adjunctive use of professional subgingival irrigation with scaling and root planing (SRP) has been found to be beneficial in eradicating the residual microorganisms in the pocket. Objective To evaluate the effect of ozonized water subgingival irrigation on microbiologic parameters and clinical parameters namely Gingival index, probing pocket depth, and clinical attachment level. Materials and Methods Thirty chronic periodontitis patients with probing pocket depth ≥6mm on at least one tooth on contra lateral sides of opposite arches were included in the study. The test sites were subjected to ozonized water subgingival irrigation with subgingival irrigation device fitted with a modified subgingival tip. Control sites were subjected to scaling and root planing only. The following clinical parameters were recorded initially and after 4 weeks at the test sites and control sites. Plaque Index, Gingival Index, probing pocket depth, clinical attachment level. Microbiologic sampling was done for the test at the baseline, after scaling, immediately after ozonized water subgingival irrigation and after 4 weeks. In control sites microbiologic sampling was done at the baseline, after scaling and after 4 weeks. The following observations were made after 4 weeks. The results were statistically analysed using independent t-test and paired t-test. Result Test sites showed a greater reduction in pocket depth and gain in clinical attachment compared to control sites. The total anaerobic counts were significantly reduced by ozonized water subgingival irrigation along with SRP compared to SRP alone. Conclusion Ozonized water subgingival irrigation can improve the clinical and microbiological parameters in patients with chronic periodontitis when used as an adjunct to scaling and root planing. PMID:26436042

  13. Integrated management of water resources demand and supply in irrigated agriculture from plot to regional scale

    NASA Astrophysics Data System (ADS)

    Schütze, Niels; Wagner, Michael

    2016-05-01

    Growing water scarcity in agriculture is an increasing problem in future in many regions of the world. Recent trends of weather extremes in Saxony, Germany also enhance drought risks for agricultural production. In addition, signals of longer and more intense drought conditions during the vegetation period can be found in future regional climate scenarios for Saxony. However, those climate predictions are associated with high uncertainty and therefore, e.g. stochastic methods are required to analyze the impact of changing climate patterns on future crop water requirements and water availability. For assessing irrigation as a measure to increase agricultural water security a generalized stochastic approach for a spatial distributed estimation of future irrigation water demand is proposed, which ensures safe yields and a high water productivity at the same time. The developed concept of stochastic crop water production functions (SCWPF) can serve as a central decision support tool for both, (i) a cost benefit analysis of farm irrigation modernization on a local scale and (ii) a regional water demand management using a multi-scale approach for modeling and implementation. The new approach is applied using the example of a case study in Saxony, which is dealing with the sustainable management of future irrigation water demands and its implementation.

  14. Restructuration of the water tariff system for irrigation districts in Mexico

    NASA Astrophysics Data System (ADS)

    Olaiz, P. A.

    1981-05-01

    The tariffs charged for irrigation and drainage services in irrigation districts in Mexico are lower than the actual costs, and as a result a subsidy is required to allow the systems to operate. This subsidy has increased rapidly since 1971, and the tariffs do not offer sufficient economic incentives to promote efficiency in the use of water for irrigation. This paper deals with the prevailing tariff structure, in an attempt to understand the economic causes for the increasing subsidy; it describes a tentative methodology for restructuration of the system based on technical, economic and social components, and presents the expected results of a first application trial of the methodology in one of Mexico's major irrigation districts.

  15. Modeling Water Infiltration in Soil Irrigated with Treated Wastewater

    NASA Astrophysics Data System (ADS)

    Gharaibeh, Mamoun; Albalasmeh, Ammar; Alghzawi, Ma'in

    2015-04-01

    Infiltration of soils irrigated with treated wastewater (TWW) was modeled using Philip, Horton, Kostiakov, and modified Kostiakov. Treatments were: soil irrigated with TWW for 5 years, 2 years, and a control site. Cumulative (Ft), rate of infiltration (ft), and hydraulic conductivity (HC) were measured in the field and aggregate stability (AS) in the lab. Both HC and ft were decreased with and AS was increased with TWW use and period of application. The Root Mean Squared Error (RMSE) and correlation coefficient (R2) were used to measure the goodness of fit and linearity of the relationship between models and measured data. Philip model was best to fit infiltration compared to other models. High AS values in treated areas compared to control area indicated that infiltration was more affected by pore clogging than soil dispersion and swelling,

  16. Columbia River System Operation Review : Final Environmental Impact Statement, Appendix F: Irrigation, Municipal and Industrial/Water Supply.

    SciTech Connect

    Columbia River System Operations Review; United States. Bonneville Power Administration; United States. Army. Corps of Engineers. North Pacific Division; United States. Bureau of Reclamation. Pacific Northwest Region.

    1995-11-01

    Since the 1930`s, the Columbia River has been harnessed for the benefit of the Northwest and the nation. Federal agencies have built 30 major dams on the river and its tributaries. Dozens of non-Federal projects have been developed as well. The dams provide flood control, irrigation, navigation, hydro-electric power generation, recreation, fish and wildlife, and streamflows for wildlife, anadromous fish, resident fish, and water quality. This is Appendix F of the Environmental Impact Statement for the Columbia River System, focusing on irrigation issues and concerns arrising from the Irrigation and Mitigation of impacts (M&I) working Group of the SOR process. Major subheadings include the following: Scope and process of irrigation/M&I studies; Irrigation/M&I in the Columbia Basin Today including overview, irrigated acreage and water rights, Irrigation and M&I issues basin-wide and at specific locations; and the analysis of impacts and alternative for the Environmental Impact Statement.

  17. Improving irrigation efficiency of sandy soils by subsurface water retaining membranes

    NASA Astrophysics Data System (ADS)

    Guber, Andrey; Smucker, Alvin; Berhanu, Samrawi

    2014-05-01

    Sustainable crop production in sandy soils is challenging due to low soil water holding capacity and high water permeability. The subsurface water retention technology (SWRT) is a relatively new long-term approach that offers precision control of water and nutrients in the root zone. However, multiple design of SWRT membrane configurations and spatial distributions require more modeling for best application in arid regions with relevant irrigation methods. The objective of this study was to define optimal geometric parameters of the SWRT membranes and the most accurate irrigation rates for corn production in sandy soils. HYDRUS-2D model, that describes two-dimensional water flow in unsaturated soil, was calibrated and validated on data in a large sand-filled lysimeter with SWRT membranes installed at different depths with different aspect ratios. The model adequately reproduced soil water content dynamics measured at 12 locations inside the sand profile. Then HYDRUS-2D simulations were repeated with different SWRT installation depths and aspect ratios. The installation depths in these simulations were 20 cm, 40 cm, and 60 cm, while the aspect ratios were 2:1, 3:1, 5:1 and 10:1. The results of simulations confirmed water holding capacity of the soil can be differentially controlled by aspect ratios of SWRT membranes. SWRT membranes with an aspect ratio of 2:1 substantially increased soil water content at 20-cm soil layer above the membrane, and this effect diminished with increasing aspect ratio of the membrane. Installation depth within the soil profile had no significant effect on water loss. The HYDRUS-2D simulations were repeated with SWRT installed at depth of 20 cm for sprinkle, surface drip and subsurface drip irrigation. Corn irrigation was triggered at pressure head of -30cm at a depth of 15 cm for all irrigation techniques. Simulated water losses by deep infiltration in sands without SWRT membranes approached 60% with approximately 15% losses when SWRT

  18. When should irrigators invest in more water-efficient technologies as an adaptation to climate change?

    NASA Astrophysics Data System (ADS)

    Malek, K.; Adam, J. C.; Stockle, C.; Brady, M.; Yoder, J.

    2015-12-01

    The western US is expected to experience more frequent droughts with higher magnitudes and persistence due to the climate change, with potentially large impacts on agricultural productivity and the economy. Irrigated farmers have many options for minimizing drought impacts including changing crops, engaging in water markets, and switching irrigation technologies. Switching to more efficient irrigation technologies, which increase water availability in the crop root zone through reduction of irrigation losses, receives significant attention because of the promise of maintaining current production with less. However, more efficient irrigation systems are almost always more capital-intensive adaptation strategy particularly compared to changing crops or trading water. A farmer's decision to switch will depend on how much money they project to save from reducing drought damages. The objective of this study is to explore when (and under what climate change scenarios) it makes sense economically for farmers to invest in a new irrigation system. This study was performed over the Yakima River Basin (YRB) in Washington State, although the tools and information gained from this study are transferable to other watersheds in the western US. We used VIC-CropSyst, a large-scale grid-based modeling framework that simulates hydrological processes while mechanistically capturing crop water use, growth and development. The water flows simulated by VIC-CropSyst were used to run the RiverWare river system and water management model (YAK-RW), which simulates river processes and calculates regional water availability for agricultural use each day (i.e., the prorationing ratio). An automated computational platform has been developed and programed to perform the economic analysis for each grid cell, crop types and future climate projections separately, which allows us to explore whether or not implementing a new irrigation system is economically viable. Results of this study indicate that

  19. A farm pond water irrigation management system in Mid-South United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the mid-southern United States, though most states receive more than 1000 mm of annual precipitation, only 20% irrigation is from surface water in this region. The majority of rainfall occurs in fall, winter and spring, but water deficit still exists during crop critical growing season from May t...

  20. Stover removal effects on seasonal soil water availability under full and deficit irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Removing corn (Zea mays L.) stover for livestock feed or bioenergy feedstock may impact water availability in the soil profile to support crop growth. The role of stover in affecting soil profile water availability will depend on annual rainfall inputs as well as irrigation level. To assess how res...

  1. Comparison of microbial quality of irrigation water delivered in aluminum and PVC pipes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial quality of irrigation water attracts substantial attention due to the increased incidence of gastrointestinal illness caused by contaminated produce. Little is known about the changes in microbial quality of water during its delivery to crops. Studies were conducted to compare the biofilm ...

  2. Setpoints for Potato Irrigation using Real-time Continuous Monitoring of Soil Water Content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate availability of water during the potato growing season is critical for production of high yields of premium processing quality tubers. Real-time, continuous monitoring of soil water content in the soil profile can be used to develop irrigation setpoints to ensure adequate availability of w...

  3. Near-surface soil water and temperature for SDI, LEPA, and spray irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Near-surface soil temperatures and volumetric soil water contents were compared for SDI, LEPA, and spray irrigation in a Pullman clay loam soil planted in cotton. Soil temperatures were measured by type-T thermocouples and volumetric water contents were measured by time domain reflectometry (TDR) in...

  4. Salinity and Alkaline pH in Irrigation Water Affect Marigold Plants: II. Mineral Ion Relations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scarcity of water of good quality for landscape irrigation is of outmost importance in arid and semiarid regions due to the competition with urban population. This is forcing the use of degraded waters with high levels of salinity and high pH, which may affect plant establishment and growth. The o...

  5. Survival of Salmonella on spinach leaves treated with contaminated irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Salmonella outbreaks have been associated with the consumption of fresh produce. The produce may be contaminated with Salmonella during on-farm contact with contaminated water. Transmission of Salmonella from contaminated irrigation water to spinach plants in growth chamber settings ...

  6. A crop water stress index and time threshold for automatic irrigation scheduling of grain sorghum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variations of the Crop Water Stress Index (CWSI) have been used to characterize crop water stress and schedule irrigations. For the most part, this thermal-based stress index has been calculated from measurements taken once daily or over a short period of time, in both cases near solar noon. A met...

  7. Evaluation of measured and simulated cotton water use and yield under full and deficit irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The AquaCrop model simulates crop growth, water use, yield, and water use efficiency of several crops including cotton. The model is intended to be useful for irrigation planning and management, and it attempts to balance simplicity and accuracy so that it can be applied in locations where weather a...

  8. Comparative analysis of water quality between runoff entrance and middle of recycling irrigation reservoirs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recycling irrigation reservoirs (RIRs) are an emerging aquatic ecosystem of critical importance, for conserving and protecting increasingly scarce water resources. Here we compare water quality between runoff entrance and middle of four RIRs in nurseries in Virginia (VA) and Maryland (MD). Surface w...

  9. Groundwater characterization and selection of suitable water type for irrigation in the western region of Bangladesh

    NASA Astrophysics Data System (ADS)

    Tanvir Rahman, Mirza A. T. M.; Saadat, A. H. M.; Islam, Md. Safiqul; Al-Mansur, Md. Abdullah; Ahmed, Shamim

    2014-11-01

    The main source of irrigation water in Bangladesh is groundwater, hence its quality needs to be ensured; otherwise, it can damage soil and reduce crop production. In current research, work by analyzing hydrogeochemical characteristics of groundwater different water types have been assessed to find out the suitable irrigation water of Godagari upazila in the western zone of Bangladesh. Studied parameters include pH, EC, TDS, K+, Na+, Ca2+, Mg2+, Fe2+, Cl-, Br-, NO3 - and SO4 2- along with sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium bicarbonate (RSBC), permeability index (PI), magnesium adsorption ratio (MAR), Kelley's ratio (KR), Mg:Ca and Na:Ca. XLSTAT and AquaChem software were used to perform factor analysis and determine water types of groundwater, respectively. The mean trends of cations and anions of the study area are Na+ > Ca2+ > Mg2+ > K+ > Fe2+ and Cl- > HCO3 - > SO4 2- > NO3 - where silicate-weathered minerals influence the groundwater quality of the study area. Except PI all parameters satisfy irrigation water standards. However, Na-Ca-Mg and Na-Ca-Cl types of water need to be under observation for any future changes since SSP is not satisfied for both of them and considering KR Na-Ca-Cl water type is not suited. Except these two groups, Ca-Na-Mg and Ca-Na-Mg-Cl water types are suitable for irrigation.

  10. Energy and Water Conservation Curriculum Development in Irrigation Technology for the Pacific Northwest. Final Report.

    ERIC Educational Resources Information Center

    Peterson, James R.

    This project was conducted to develop curriculum materials for classes in energy and water conservation for the Irrigation Technology Program at Walla Walla Community College. To develop the curriculum, the principal investigator read and analyzed materials on the subjects of water and energy conservation, participated in a short course on drip…

  11. Crop Insurance Increases Water Withdrawals for Irrigation in Agriculture

    NASA Astrophysics Data System (ADS)

    Konar, M.; Deryugina, T.; Lin, X.

    2015-12-01

    Agricultural production remains particularly vulnerable to weather fluctuations and extreme events, such as droughts, floods, and heat waves. Crop insurance is a risk management tool that has been developed to mitigate some of this weather risk and protect farmer income in times of poor production. However, it is not clear what the implications of crop insurance are for crop irrigation. By providing a guaranteed level of income in case of crop failure, crop insurance can reduce the farmer's incentive to irrigate. Thus, crop insurance can decrease water use in times of drought and promote water sustainability. However, to minimize this "moral hazard", the insurer may require farmers to irrigate crops more than necessary. Further, by shifting crop production, crop insurance may increase demand for water. Thus, it is unclear whether crop insurance increases or decreases crop water use. Here, we determine the empirical relationship between crop insurance and irrigation withdrawals in the United States. To establish causality, we exploit variation in crop insurance policies over time, using an instrumental variables approach. We find that a 1% increase in insured crop acreage leads to a 0.223% increase in irrigation withdrawals, primarily from groundwater aquifers.

  12. Screening of 47 organic microcontaminants in agricultural irrigation waters and their soil loading.

    PubMed

    Calderón-Preciado, D; Jiménez-Cartagena, C; Matamoros, V; Bayona, J M

    2011-01-01

    Reclaimed water usage for crop irrigation is viewed both as an excellent sustainable water source and as a potential entrance for emerging organics into the food chain. This concern is backed by the already documented pollutant crop uptake potential. In the present study, irrigation waters used in agricultural fields (Torroella de Montgri, NE Spain) were screened for 47 analytes in a two year study (2007-2008). A total of 26 contaminants belonging to different chemical classes namely, pesticides, pharmaceuticals, personal care products, phenolic estrogens, antioxidants and disinfection by-products, were detected. Marked differences in concentration trends for the different chemical classes were evidenced from 2007 to 2008, and attributed to a persistent drought endured by the region in 2008. Also, loading mass rates of chemical classes were estimated based on crop irrigation regimes and they ranged from 0.8 to 121.3 g ha(-1) per crop cycle. These values were contrasted with those obtained for other water sources from countries where crop irrigation is commonly practiced. Finally, crops grown under these irrigation regimes, namely alfalfa and apple, were analyzed and 5 anthropogenic compounds were identified and quantitated, whose concentrations ranged from 13.9 to 532 ng g(-1) (fresh weight). PMID:20961595

  13. Non-invasive treatment of intractable posterior epistaxis with hot-water irrigation.

    PubMed

    Schlegel-Wagner, Christoph; Siekmann, Ulrich; Linder, Thomas

    2006-03-01

    Posterior nose bleeding is a frequent and challenging emergency. The authors report their experience using hot water irrigation as a non-invasive treatment option for posterior epistaxis. Between January 2003 and January 2005 a group of 103 patients were enrolled in this prospective study evaluating the effectiveness of a "hot water irrigation" technique to control acute posterior nose bleeding. All patients with posterior epistaxis were included, whereas anterior epistaxis was controlled using conventional methods. The patient's nose was initially anaesthetized with topical Tetracain 4% (without vasoconstriction) and a modified epistaxis-balloon-catheter was introduced into the bleeding nasal cavity obstructing the choana. The bleeding nasal cavity was continuously irrigated using 500 ml of 50 degrees C hot water. In a total of 84 patients (82%) the bleeding was successfully and permanently stopped. Forty-seven of these patients (56%) regularly took antiplatelet agents or anticoagulants. The method failed in 19 of 103 patients (18%). In the group with unsuccessful irrigation, 11 patients (58%) were receiving treatment with antiplatelet agents or anticoagulants. Their proportion was not different from the successfully treated group. The success rate of hot water irrigation as non-invasive treatment of posterior epistaxis appears at least as effective as conventional methods. However it avoids painful packing, hospitalizations, or immediate surgery, and allows the patient to breath normally through his open nasal cavities. PMID:16550958

  14. [Effects of irrigation amount on morphological characteristics and water use of Jatropha curcas].

    PubMed

    Yang, Qi-Liang; Zhang, Jing; Liu, Xiao-Gang; Liu, Yan-Wei; Yang, Ju-Rui

    2014-05-01

    Jatropha curcas is the most promising energy tree, and soil moisture is the key factor which affects the seedling quality and water use efficiency of J. curcas. With aims to evaluate the effect of different irrigation amount on growth, morphological characteristics and water use of J. curcas, a pot experiment was conducted with four irrigation amounts, i. e., W1:472.49 mm, W2: 228.79 mm, W3:154.18 mm and W4:106.93 mm, respectively. Compared with W1 treatment, the leaf area and stem cross-section area of base significantly decreased in W2, W3 and W4 treatments, but Huber value significantly increased, which could improve the efficiency of water transfer from root to shoot, thus enhance the capability of resistance to drought stress. Compared with W, treatment, the healthy index of J. curcas seedlings decreased slightly in W2 treatment but significantly decreased in W3 and W4 treatments. Hence, the irrigation amount from 228.79 to 472.49 mm was beneficial to increase the healthy index of J. curcas seedlings. Compared with W1 treatment, irrigation water was saved by 67.4% in W3 treatment, and the total dry mass and evapotranspiration significantly decreased by 17.4% and 68.6%, and the irrigation water use efficiency and total water use efficiency increased by 153.2% and 163.2%, respectively. In the condition of this study, the irrigation amount of 154.18 mm was beneficial to increase water use efficiency. PMID:25129933

  15. Soil and stream-water impacts of sewage effluent irrigation onto steeply sloping land

    SciTech Connect

    Speir, T.W.; Schaik, A.P. van; Kettles, H.A.; Vincent, K.W.; Campbell, D.J.

    1999-08-01

    In a pilot study, the authors investigated how irrigation of secondary sewage effluent onto steeply sloping land affected soil physical, chemical, and biochemical properties, the composition of soil- and surface-waters and the vegetation of the site. The 3.36-ha site received up to 44 mm effluent/wk for 65 wk. Irrigation significantly improved total- and Olsen-P status of the soils and greatly enhanced nitrification potential. Respiration increased with increasing soil water content, but microbial biomass was not greatly affected by irrigation. Soil phosphatase activity decreased with increasing P fertility. Soil physical properties were not affected by effluent and hydraulic conductivities were sufficient to conduct water into and through the soil profiles. Soil- and surface-water NO{sub 3}{sup {minus}}-N concentrations increased markedly, especially in the second half of the trial when soil nitrification rates were also high. However, the streamwater NO{sub 3}{sup {minus}}-N concentrations remained well below the drinking water limit concentration of 11.3 g m{sup {minus}3}. In contrast, streamwater NH{sub 4}{sup +}-N and PO{sub 4}{sup 3{minus}}-P concentrations remained low and results indicated that concentrations of PO{sub 4}{sup 3{minus}}-P in river water, resulting from a full-scale irrigation scheme, would not exceed the target limit level of 0.0056 g m{sup {minus}3}. Irrigation accelerated natural successional changes in the vegetation, with a decline in undesirable fire-prone and shrubby species and an increase in native trees and tree ferns. These results demonstrated that, in the short term at least, a carefully designed and implemented irrigation scheme on steepland could renovate secondary sewage effluent, without adversely affecting soil properties and surface water quality.

  16. Regulated deficit irrigation and the recovery of water relations in pistachio trees.

    PubMed

    Guerrero, J; Moriana, A; Pérez-López, D; Couceiro, J F; Olmedilla, N; Gijón, M C

    2006-01-01

    Recovery of water status in water-stressed pistachio trees (Pistacia vera L. cv. Kerman) was investigated by subjecting trees to regulated deficit irrigation (RDI) (60% of crop evapotranspiration rate, ET(c)) during stages I and II of fruit development (FD) followed by full irrigation during FD stage III (kernel-filling). Trees irrigated at 100% ET(c) throughout FD stages I, II and III served as controls. Water-stress severity was characterized by changes in soil water content and midday stem water potential (Psi(md)). Midday leaf conductance (g(1)) and trunk diameter variation (TDV) were also measured. In RDI trees, the lowest Psi(md) value, -1.8 MPa, occurred at the end of the RDI period. The corresponding value for the control trees was around -1.1 MPa. Although the RDI treatment affected gas exchange later than Psi(md), the greatest reductions in gas exchange (60% of control values) also appeared at the end of the RDI period. There were significant differences in TDV between control and RDI trees at the end of the RDI period. Although plant water status recovered within 20 days of resuming irrigation, the TDV values indicated a longer period might be necessary for complete recovery. Recovery of g(1) was faster than that of Psi(md), although differences in TDV between control and RDI trees indicated that gas exchange recovered later than Psi(md). The slow recovery of pistachio trees during FD stage III from water stress imposed during FD stages I and II suggests that irrigation should exceed 100% ET(c) during FD stage III or that more extensive irrigation should commence before the end of FD stage II. PMID:16203718

  17. Irrigation Strategies and Crop Breeding As Complementary Measures for Improved Water Management and Ecosystem Services

    NASA Astrophysics Data System (ADS)

    Vico, G.; Manzoni, S.; Weih, M.; Porporato, A. M.

    2014-12-01

    The projected population growth and changes in climate and dietary habits will further increase the pressure on water resources globally. Within precision farming, a host of technical solutions has been developed to reduce water consumption for agricultural uses. Examples are the shift from scheduled to demand-based irrigation and the use of sophisticated water distribution techniques. The next frontier for a more sustainable agriculture is the combination of reduced water requirements with enhanced ecosystem services. Currently, staple grains are obtained from annuals crops. Enhanced ecosystem services could be obtained shifting from annual to perennial crops, obtained by means of targeted breeding. In fact, perennial plants, with their continuous soil cover and the higher allocation of resources to the below ground, contribute to the reduction of soil erosion, water and nutrient losses, while enhancing carbon sequestration in the root zone. We explore here the implications for water management at the field- to farm-scale of both improved irrigation methods and targeted breeding. A probabilistic description of the soil water balance and crop development is employed to quantify water requirements and yields and their inter-annual variability, as a function of rainfall patterns, soil and crop features. Optimal irrigation strategies are thus defined in terms of maximization of yield and minimization of required irrigation volumes and their inter-annual variability. The probabilistic model is parameterized based on an extensive meta-analysis of traits of co-generic annual and perennial species (including both selected and wild species) to explore the consequences for water requirements of shifting from annual to perennial crops under current and future climates. The larger and more developed roots of perennial crops may allow a better exploitation of soil water resources than annual species. At the same time, perennial crops may require adequate water supply for

  18. Incentives to adopt irrigation water saving measures for wetlands preservation: An integrated basin scale analysis

    NASA Astrophysics Data System (ADS)

    Nikouei, Alireza; Zibaei, Mansour; Ward, Frank A.

    2012-09-01

    SummaryPreserving natural wetlands is a growing challenge as the world faces increased demand for water. Drought, climate change and growing demands by users aggravate the issue. The conflict between irrigated agriculture and wetland services presents a classic case of competition. This paper examines an institutional mechanism that offers an incentive to farmers to adopt water conservation measures, which in turn could reduce overall water use in irrigated agriculture within a selected basin. Reduced water demands could provide the additional water needed for wetland preservation. We present an analytical empirical model implemented through the development of an integrated basin framework, in which least-cost measures for securing environmental flows to sustain wetlands are examined for the Zayandeh-Rud River Basin of central Iran. To test this idea, two policies - one with and one without an incentive - are analyzed: (a) reduced agricultural diversions without a water conservation subsidy, and (b) reduced agricultural diversions with a water conservation subsidy. The policies are evaluated against a background of two alternative water supply scenarios over a 10-year period. Results reveal that a water conservation subsidy can provide incentives for farmers to shift out of flood irrigation and bring more land into production by adopting water-saving irrigation technologies. The policy increases crop yields, raises profitability of farming, and increases the shadow price of water. Although the conservation subsidy policy incurs a financial cost to the taxpayer, it could be politically and economically attractive for both irrigators and environmental stakeholders. Results open the door for further examination of policy measures to preserve wetlands.

  19. A comparative study of strains of salmonella isolated from irrigation waters, vegetables and human infections.

    PubMed Central

    Garcia-Villanova Ruiz, B.; Cueto Espinar, A.; Bolaños Carmona, M. J.

    1987-01-01

    A total of 181 samples of irrigation water from the farmlands of Granada were examined for the presence of Salmonella spp. At the same time 849 samples of the crops from these farmlands and of vegetables sold in city market-places were studied. Sampling was done regularly over the period of study which ran from March 1981 to February 1983. Isolates from these sources were compared with 93 salmonellas isolated from human pathological material at various hospitals of the city of Granada from 1979-80, and again from 1981-3. The most commonly isolated serotypes of human origin were S. typhimurium and S. enteritidis. In irrigation waters and in crops, S. typhimurium, S. kapemba, S. london and S. blockley were found to be the most common. The results indicate a close relationship between the isolates from the irrigation waters and those from the vegetables, but their relationship to prevalent human infections is less clear. PMID:3595745

  20. The Bureau of Reclamation's new mandate for irrigation water conservation: Purposes and policy alternatives

    SciTech Connect

    Moore, M.R. )

    1991-02-01

    Although the Bureau of Reclamation adopted a new mission as a water management agency, social purposes of the mission and methods of accomplishing the purposes remain undefined. A broad consensus agrees that a central feature of the agency's management program should be irrigation water conservation. This paper describes three purposes of irrigation water conservation: achieving economic efficiency of water allocation, improving environmental quality of western river systems, and satisfying outstanding Native American water claims. Five policy instruments are described as alternative methods of inducing conservation: quantity-based regulation, price-based regulation, transferable water use permits, conservation subsidies, and decentralization of ownership of Reclamation facilities. Two findings are: (1) price-based regulation may not produce water conservation and (2) conservation policy instruments should be chosen with reference to their ability to achieve the purposes of federal water conservation policy. An example illustrates quantitative effects on farm income of the alternative instruments.

  1. Occurrence of vancomycin-resistant and -susceptible Enterococcus spp. in reclaimed water used for spray irrigation.

    PubMed

    Carey, Stephanie Ann; Goldstein, Rachel E Rosenberg; Gibbs, Shawn G; Claye, Emma; He, Xin; Sapkota, Amy R

    2016-05-01

    Reclaiming municipal wastewater for agricultural, environmental, and industrial purposes is increasing in the United States to combat dwindling freshwater supplies. However, there is a lack of data regarding the microbial quality of reclaimed water. In particular, no previous studies have evaluated the occurrence of vancomycin-resistant enterococci (VRE) in reclaimed water used at spray irrigation sites in the United States. To address this knowledge gap, we investigated the occurrence, concentration, and antimicrobial resistance patterns of VRE and vancomycin-susceptible enterococci at three U.S. spray irrigation sites that use reclaimed water. We collected 48 reclaimed water samples from one Mid-Atlantic and two Midwest spray irrigation sites, as well as their respective wastewater treatment plants, in 2009 and 2010. Samples were analyzed for total enterococci and VRE using standard membrane filtration. Isolates were purified and then confirmed using biochemical tests and PCR. Antimicrobial susceptibility testing was conducted using the Sensititre® microbroth dilution system. Data were analyzed by two-sample proportion tests and one-way analysis of variance. We detected total enterococci and VRE in 71% (34/48) and 4% (2/48) of reclaimed water samples, respectively. Enterococcus faecalis was the most common species identified. At the Mid-Atlantic spray irrigation site, UV radiation decreased total enterococci to undetectable levels; however, subsequent storage in an open-air pond at this site resulted in increased concentrations of enterococci. E. faecalis isolates recovered from the Mid-Atlantic spray irrigation site expressed intrinsic resistance to quinupristin/dalfopristin; however, non-E. faecalis isolates expressed resistance to quinupristin/dalfopristin (52% of isolates), vancomycin (4%), tetracycline (13%), penicillin (4%) and ciprofloxacin (17%). Our findings show that VRE are present in low numbers in reclaimed water at point-of-use at the sampled spray

  2. Arsenic removal from flowing irrigation water in bangladesh: impacts of channel properties.

    PubMed

    Lineberger, Ethan M; Badruzzaman, A Borhan M; Ali, M Ashraf; Polizzotto, Matthew L

    2013-11-01

    Across Bangladesh, dry-season irrigation with arsenic-contaminated well water is loading arsenic onto rice paddies, leading to increased arsenic concentrations in plants, diminished crop yields, and increased human health risks. As irrigation water flows through conveyance channels between wells and rice fields, arsenic concentrations change over space and time, indicating that channels may provide a location for removing arsenic from solution. However, few studies have systematically evaluated the processes controlling arsenic concentrations in irrigation channels, limiting the ability to manipulate these systems and enhance arsenic removal from solution. The central goal of this study was to quantify how channel design affected removal of dissolved arsenic from flowing irrigation water. Field experiments were conducted in Bangladesh using a chemically constant source of arsenic-contaminated irrigation water and an array of constructed channels with varying geometries. The resulting hydraulic conditions affected the quantity of arsenic removed from solution within the channels by promoting known hydrogeochemical processes. Channels three times the width of control channels removed ∼3 times the mass of arsenic over 32 min of flowing conditions, whereas negligible arsenic removal was observed in tarp-lined channels, which prevented soil-water contact. Arsenic removal from solution was ∼7 times higher in a winding, 200-m-long channel than in the straight, 45-m-long control channels. Arsenic concentrations were governed by oxidative iron-arsenic coprecipitation within the water column, sorption to soils, and phosphate competition. Collectively, these results suggest that better design and management of irrigation channels may play a part in arsenic mitigation strategies for rice fields in Southern Asia. PMID:25602413

  3. Microbiological water quality in a large irrigation system: El Valle del Yaqui, Sonora México.

    PubMed

    Gortáres-Moroyoqui, Pablo; Castro-Espinoza, L; Naranjo, Jaime E; Karpiscak, Martin M; Freitas, Robert J; Gerba, Charles P

    2011-01-01

    The primary objective of this study was to determine the microbial water quality of a large irrigation system and how this quality varies with respect to canal size, impact of near-by communities, and the travel distance from the source in the El Valle del Yaqui, Sonora, México. In this arid region, 220,000 hectares are irrigated with 80% of the irrigation water being supplied from an extensive irrigation system including three dams on the Yaqui River watershed. The stored water flows to the irrigated fields through two main canal systems (severing the upper and lower Yaqui Valley) and then through smaller lateral canals that deliver the water to the fields. A total of 146 irrigation water samples were collected from 52 sample sites during three sampling events. Not all sites could be accessed on each occasion. All of the samples contained coliform bacteria ranging from 1,140 to 68,670 MPN/100 mL with an arithmetic mean of 11,416. Ninety-eight percent of the samples contained less than 1,000 MPN/100 mL Escherichia coli, with an arithmetic mean of 291 MPN/100 mL. Coliphage were detected in less than 30% of the samples with an arithmetic average equal to 141 PFU/100 mL. Enteroviruses, Cryptosporidium oocysts, and Giardia cysts were also detected in the canal systems. No significant difference was found in the water quality due to canal system (upper or lower Yaqui Valley), canal-size (main vs. lateral), distance from source, and the vicinity of human habitation (presence of various villages and towns along the length of the canals). There was a significant decrease in coliforms (p < 0.011) and E. coli (< 0.022) concentrations as travel distance increased from the City of Obregón. PMID:22175874

  4. 25 CFR 171.215 - What if the elevation of my farm unit is too high to receive irrigation water?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false What if the elevation of my farm unit is too high to receive irrigation water? 171.215 Section 171.215 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.215 What if the elevation of my farm unit is too high to...

  5. SWAP Modeling Results of Monitored Soil Water Moisture Data of Irrigation Experimental Study

    NASA Astrophysics Data System (ADS)

    Zeiliger, A.; Garsia-Orenes, F.; van den Elsen, E.; Mataix-Solera, J.; Semenov, V.

    2009-04-01

    In arid and semiarid zones of the Mediterranean regions a shortage of fresh water resources constitutes some time dramatic problem. In these regions with growing population and the scarce of rainfall irregularity in time during growing season an efficient use of water irrigation became a main challenge for future extensive agriculture development. In the frame of FP6 Water-Reuse project 516731 project a special field experimentation has been carried out in Alicante Region of Spain (Location UTM X: 693.809, Y: 4.279.922, Z: 626) on a Sandy Typic Xerofkuvent (Soil Survey Staff, 1999), Calcaric Fluvisol (WRB, FAO, 1989). with aim to investigate water regime in water repellent soils under irrigation of vine Vitus Labrusca. During field experimentation from 2006 till 2008 on 9 plots, there the same regime of irrigation water application was maintained, a monitoring of weather parameters was done by automatic meteorological station as well as a monitoring of soil water moisture was done by set of data-loggers and TDR-soil moisture sensors ECO-2 installed at different depts. SWAP model was used to simulate water regime of irrigated plots. Empirical coefficients of van Genuchten-Mualem's equations were calculated by pedotransfer functions derived from HYPRES data base using measured values of bulk density, organic matter content and soil texture. Testing of validity of the use of estimated curves was done by comparison with unsaturated soil hydraulic parameters of water retention and hydraulic conductivity measured in vitro by Wind's method on soil samples. Calibration of SWAP model for each plot was done on measured soil moisture data of irrigation events by adjusting a value of saturated hydraulic coefficient. Verification of the SWAP model was done by full range of experimental data. Similarity and non-similarity of the water regime at experimental plots as well as results of verification of SWAP model were analyzed

  6. An economic framework for valuing information in water scarce irrigation districts

    NASA Astrophysics Data System (ADS)

    Kaune, Alexander; Werner, Micha; Karimi, Poolad; de Fraiture, Charlotte

    2015-04-01

    Data and information plays a crucial role in quantifying the abundance of the available water resource and the demand placed on it in water scarce regions, and is central to decision making. This is particularly so for water allocation decisions in large irrigation districts. However, in most irrigation schemes data collection is normally limited due to the economic investments required. As a result, water allocation decisions are normally taken based on incomplete or uncertain data on the current or forecast situation, leading to less optimal decisions being taken in system planning and operation. Wrong water allocation decisions can lead to economic loss in agricultural production, implying low performance of the system and possible impact on the users' livelihoods. The objective of this research is to assess available frameworks in valuing information and to adapt these to support water allocation decisions in irrigation districts. Water allocation decisions made in the planning of irrigation districts as well as in their operation will be evaluated through a decision framework that considers a discrete set of options, each generating different agricultural production loss scenarios relative to uncertain water scarcity conditions. Additional information obtained from improved data can support better decision making and thus constitutes added value. This added value can be interpreted as the marginal benefit of the improved data. The marginal benefit of information will be determined following an economic framework based on the Relative Economic Value theory that is applied in making decisions in a Bayesian setting. Through this framework it is expected to provide economic values of information in support of water allocation decisions in vulnerable irrigation districts. This is an essential step to provide insight on the value of information in water allocation decisions in planning and operation, and ultimately to reduce agricultural production loss.

  7. Demand driven decision support for efficient water resources allocation in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Schuetze, Niels; Grießbach, Ulrike Ulrike; Röhm, Patric; Stange, Peter; Wagner, Michael; Seidel, Sabine; Werisch, Stefan; Barfus, Klemens

    2014-05-01

    Due to climate change, extreme weather conditions, such as longer dry spells in the summer months, may have an increasing impact on the agriculture in Saxony (Eastern Germany). For this reason, and, additionally, declining amounts of rainfall during the growing season the use of irrigation will be more important in future in Eastern Germany. To cope with this higher demand of water, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from the optimized agronomic response at farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF) which provide the estimated yield subject to the minimum amount of irrigation water. These functions take into account the different soil types, crops and stochastically generated climate scenarios. By applying mathematical interpolation and optimization techniques, the SCWPF's are used to compute the water demand considering different constraints, for instance variable and fix costs or the producer price. This generic approach enables the computation for both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance Irrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies for an effective and efficient utilization of water in order to meet future demands. The prototype is implemented as a web-based decision support system and it is based on a service-oriented geo-database architecture.

  8. Effects of alternate drip irrigation and superabsorbent polymers on growth and water use of young coffee tree.

    PubMed

    Liu, Xiaogang; Li, Fusheng; Yang, Qiliang; Wang, Xinle

    2016-07-01

    To obtain optimal irrigation management for young coffee tree, the effects of alternate drip irrigation (ADI) and superabsorbent polymers on physiology, growth, dry mass accumulation and water use on one-year old Coffea arabica L. tree were investigated. This experiment had three drip irrigation methods, i.e., conventional drip irrigation (CDI), alternate drip irrigation (ADI) and fixed drip irrigation (FDI), and two levels of superabsorbent polymers, i.e., no superabsorbent polymers (NSAP) and added superabsorbent polymers (SAP). Compared to CDI, ADI saved irrigation water by 32.1% and increased water use efficiency (WUE) by 29.9%. SAP increased root-shoot ratio, total dry mass and WUE by 20.3, 24.9 and 33.0%, respectively, when compared to NSAP. Compared to CDI with NSAP treatment, ADI with SAP treatment increased total dry mass by 13.8% and saved irrigation water by 34.4%, thus increased WUE by 73.4%, and it increased root activity, the contents of chlorophyll and soluble sugar in leaves by 162.4, 38.0 and 8.5%, but reduced the contents of proline and malondialdehyde in leaves by 7.2 and 9.7%, respectively. Thus, alternate drip irrigation with superabsorbent polymers increased the growth and WUE of young Coffea arabica L. tree and was optimal irrigation management for young coffee tree. PMID:27498491

  9. Persistence of Indicator and Pathogenic Microorganisms in Broccoli following Manure Spreading and Irrigation with Fecally Contaminated Water: Field Experiment.

    PubMed

    Généreux, Mylène; Breton, Marie Jo; Fairbrother, John Morris; Fravalo, Philippe; Côté, Caroline

    2015-10-01

    In 2011 and 2012, trials consisting of experimental plots were carried out to evaluate the presence of pathogenic (Listeria monocytogenes, Salmonella) and prevalence of indicator (Escherichia coli) microorganisms in broccoli fertilized with liquid hog manure or mineral fertilizers and irrigated zero, one, or two times with E. coli-contaminated water. In 2011, results showed that E. coli contamination in broccoli heads was affected by the interval between irrigation and sampling (P = 0.0236), with a significant decrease between the first and third day following irrigation (P = 0.0064). In 2012, irrigation frequency significantly increased E. coli prevalence in broccoli samples (P = 0.0499). In 2012, E. coli counts in the soil were significantly influenced by the type of fertilizer applied, as plots receiving liquid hog manure showed higher bacterial counts (P = 0.0006). L. monocytogenes was recovered in one broccoli sample, but geno-serogrouping differentiated the isolate from those recovered in manure and irrigation water. The L. monocytogenes serogroup IIA, pulsotype 188 strain was found in six soil samples and in irrigation water applied 5 days before soil sampling. This study highlights the link between E. coli levels in irrigation water, irrigation frequency, and interval between irrigation and harvest on produce contamination. It also demonstrates that L. monocytogenes introduced into the soil following irrigation can persist for up to 5 days. PMID:26408125

  10. Climate change, water rights, and water supply: The case of irrigated agriculture in Idaho

    NASA Astrophysics Data System (ADS)

    Xu, Wenchao; Lowe, Scott E.; Adams, Richard M.

    2014-12-01

    We conduct a hedonic analysis to estimate the response of agricultural land use to water supply information under the Prior Appropriation Doctrine by using Idaho as a case study. Our analysis includes long-term climate (weather) trends and water supply conditions as well as seasonal water supply forecasts. A farm-level panel data set, which accounts for the priority effects of water rights and controls for diversified crop mixes and rotation practices, is used. Our results indicate that farmers respond to the long-term surface and ground water conditions as well as to the seasonal water supply variations. Climate change-induced variations in climate and water supply conditions could lead to substantial damages to irrigated agriculture. We project substantial losses (up to 32%) of the average crop revenue for major agricultural areas under future climate scenarios in Idaho. Finally, farmers demonstrate significantly varied responses given their water rights priorities, which imply that the distributional impact of climate change is sensitive to institutions such as the Prior Appropriation Doctrine.

  11. Water balance in irrigation districts. Uncertainty in on-demand pressurized networks

    NASA Astrophysics Data System (ADS)

    Sánchez-Calvo, Raúl; Rodríguez-Sinobas, Leonor; Juana, Luis; Laguna, Francisco Vicente

    2015-04-01

    In on-demand pressurized irrigation distribution networks, applied water volume is usually controlled opening a valve during a calculated time interval, and assuming constant flow rate. In general, pressure regulating devices for controlling the discharged flow rate by irrigation units are needed due to the variability of pressure conditions. A pressure regulating valve PRV is the commonly used pressure regulating device in a hydrant, which, also, executes the open and close function. A hydrant feeds several irrigation units, requiring a wide range in flow rate. In addition, some flow meters are also available, one as a component of the hydrant and the rest are placed downstream. Every land owner has one flow meter for each group of field plots downstream the hydrant. Ideal PRV performance would maintain a constant downstream pressure. However, the true performance depends on both upstream pressure and the discharged flow rate. Theoretical flow rates values have been introduced into a PRV behavioral model, validated in laboratory, coupled with an on-demand irrigation district waterworks, composed by a distribution network and a multi-pump station. Variations on flow rate are simulated by taking into account the consequences of variations on climate conditions and also decisions in irrigation operation, such us duration and frequency application. The model comprises continuity, dynamic and energy equations of the components of both the PRV and the water distribution network. In this work the estimation of water balance terms during the irrigation events in an irrigation campaign has been simulated. The effect of demand concentration peaks has been estimated.

  12. Separating nitrogen fertilizer and irrigation water application in an alternating furrow irrigation system for maize production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient use of water and nitrogen represents a primary concern to agricultural production in northwest of China. A two-year field experiment was conducted to assess and model the interactive effects between water and nitrogen (N) on maize (Zea mays L.) when grown with alternating furrow irriga...

  13. Surface soil water content spatial organization within irrigated and non-irrigated agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding soil water content variability is important for monitoring and modeling of land surface processes as well as land and water management practices. With regards to in situ probes, it is sometimes assumed that a single local measurement can represent the larger domain, mostly for practic...

  14. Occupational Exposure to Staphylococcus aureus and Enterococcus spp. among Spray Irrigation Workers Using Reclaimed Water

    PubMed Central

    Rosenberg Goldstein, Rachel E.; Micallef, Shirley A.; Gibbs, Shawn G.; He, Xin; George, Ashish; Sapkota, Amir; Joseph, Sam W.; Sapkota, Amy R.

    2014-01-01

    As reclaimed water use expands, it is important to evaluate potential occupational health risks from exposure to this alternative water source. We compared odds of colonization with methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), vancomycin-resistant enterococci (VRE), and vancomycin-susceptible enterococci (VSE) between spray irrigation workers using reclaimed water and office worker controls. Nasal and dermal swabs from 19 spray irrigation workers and 24 office worker controls were collected and analyzed for MRSA, MSSA, VRE, and VSE. Isolates were confirmed using standard biochemical tests and polymerase chain reaction assays. Antimicrobial susceptibility testing was performed by Sensititre® microbroth dilution. Data were analyzed by two-sample proportion, chi-square, Fisher’s exact tests, and logistic regression. No MRSA or VRE were detected in any samples. MSSA was detected in 26% and 29% of spray irrigators and controls, respectively. VSE was detected in 11% and 0% of spray irrigation workers and controls, respectively. The adjusted odds of MSSA, multidrug-resistant MSSA, and either MSSA or VSE colonization were greater among spray irrigation workers, however results were not statistically significant. Future studies with larger sample sizes are needed to further evaluate this relationship. PMID:24747541

  15. Yield and water use efficiency of different irrigated sugarcane cultivars in Brazil

    NASA Astrophysics Data System (ADS)

    Silva, André L. B. O.; Pires, Regina C. M.; Ohashi, Augusto Y. P.; Ribeiro, Rafael V.

    2015-04-01

    There is an increasing demand for bioenergy production to provide environmental, economic and agricultural sustainability. In this context Brazil has an important option with sugarcane cultivation. The sugarcane cultivation has been increasing in marginal and appropriate areas depending on weather conditions. In appropriate areas, such as the State of São Paulo, it is important to increase yield and quality instead of expanding new areas. In this context, irrigation becomes an important cultural practice as a guarantee and to achieve high yields. Thus, the use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to save water since water and nutrients are applied in root zone plants. As irrigation demands great volume of water, it is important to study the most responsive cultivars to adopt this technique and improve water use efficiency (WUE). Thus, this study aimed to evaluate the yield and WUE of four sugarcane cultivars irrigated by a SDI system. The experiment with the SP79-1011, IACSP94-2101, IACSP94-2094 and IACSP95-5000 cultivars was carried out in Campinas, SP, Brazil, between October 2012 and November 2013 (second ratoon). These cultivars have different canopy characteristics and development. IACSP95-5000 and IACSP94-2094 are more responsive to soil water availability and presents higher light interception when compared to IACSP94-2101 and SP79-1011. The irrigation was applied by a subsurface drip system daily and it was suspended when precipitation occurred. Crop evapotranspiration was estimated through field water balance. In order to do so the soil moisture was evaluated with capacitance probe with sensors installed at depths of 0.2, 0.3, 0.4, 0.6, 0.8 and 1.0 m. Samplings were collected to estimate yield and qualitative attributes. The water use efficiency (WUE) was estimated based on stem production per hectare reached in each cultivar divided by (1) water volume contributed considering the actual

  16. Competency-Based Horticulture. Floriculture.

    ERIC Educational Resources Information Center

    College of DuPage, Glen Ellyn, IL.

    One of two competency-based horticulture curriculum guides developed by an Illinois project, this Floriculture guide provides the classroom teacher with specific tasks determined by state industry personnel to be necessary for entry-level job placement. It is intended for horticulture education at the senior high school and two year college level.…

  17. Competency-Based Horticulture: Floriculture.

    ERIC Educational Resources Information Center

    College of DuPage, Glen Ellyn, IL.

    This competency-based horticulture curriculum guide is designed to provide secondary and postsecondary horticulture teachers with a task-oriented program in floriculture. It contains a master resource list, a listing of floriculture resources available from various states, and 89 competency task sheets organized into nine competency areas. These…

  18. Deficit irrigation and sustainable water-resource strategies in agriculture for China's food security.

    PubMed

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J

    2015-04-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant's growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources. PMID:25873664

  19. Deficit irrigation and sustainable water-resource strategies in agriculture for China’s food security

    PubMed Central

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J.

    2015-01-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant’s growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources. PMID:25873664

  20. Effects of irrigated agroecosystems: 2. Quality of soil water and groundwater in the southern High Plains, Texas

    NASA Astrophysics Data System (ADS)

    Scanlon, B. R.; Gates, J. B.; Reedy, R. C.; Jackson, W. A.; Bordovsky, J. P.

    2010-09-01

    Trade-offs between water-resource depletion and salinization need to be understood when promoting water-conservative irrigation practices. This companion paper assesses impacts of groundwater-fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water-extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are similar to those under natural ecosystems, but they accumulated over decades rather than millennia typical of natural ecosystems. Profile peak Cl concentrations (1200-6400 mg/L) correspond to irrigation efficiencies of 92-98% with respect to drainage and are attributed to deficit irrigation with minimal flushing. Perchlorate (ClO4) also accumulates under irrigated agroecosystems, primarily from irrigation water, and behaves similarly to Cl. Most NO3-N accumulation is below the root zone. Groundwater total dissolved solids (TDS) have increased by ≤960 mg/L and NO3-N by ≤9.4 mg/L since the early 1960s. Mobilization of salts that have accumulated under irrigated agroecosystems is projected to degrade groundwater much more in the future because of the essentially closed-basin status of the aquifer, with discharge occurring primarily through irrigation pumpage. TDS are projected to increase by an additional 2200 mg/L (median), ClO4 by 21 μg/L, and NO3-N by 52 mg/L. Water and salt balances should be considered in irrigation management in order to minimize salinization issues.

  1. Water saving in chufa cultivation using flat raised beds and drip irrigation

    NASA Astrophysics Data System (ADS)

    Pascual-Seva, N.; San Bautista, A.; López-Galarza, S.; Maroto, J. V.; Pascual, B.

    2012-04-01

    Chufa (Cyperus esculentus L. var. sativus), also known as tiger nut, is a typical crop in the Region of Valencia (Spain). Its tubers are used to produce a beverage called horchata. Chufa has been cultivated traditionally in ridges and furrow irrigated. Currently, the quality of water used is acceptable, there are no limitations on supply, and water is not expensive; therefore, large amounts of water are used. The European Water Framework Directive 2000/60 is based on the precautionary principle, considering preventive action for measures to be taken; thus, water use is an issue to improve. Moreover, drought periods are becoming more frequent and extended, and water is being diverted to other uses. In this two year study (2007-2008), we analysed how yield and irrigation water use efficiency (IWUE) are affected by two cultivation factors: planting strategy and irrigation system. Three planting strategies were analysed: ridges (R) and flat raised beds, with two (B2) and three (B3) plant rows along them, while two irrigation systems were compared, furrow (FI) and drip irrigation (DI). Within the beds, the effect of the position of the plant row was considered, differing among plants grown in the north (n), central (c), and south (s) rows. Distances between ridge and bed axes were 60, 80 and 120 cm for R, B2 and B3, respectively. Irrigation was based on the Volumetric Soil Water Content (VSWC), which was continuously monitored with capacitance sensors (ECH2O EC-5 in FI and multidepth capacitance sensors C-Probe in DI). Each irrigation session started when the VSWC in R dropped to 60% and 80% of field capacity in FI and DI, respectively. Each DI session lasted 60 min in 2007; while in 2008 the installation was automated, stopping each session when the sum of the VSWC at 10, 20, and 30 cm soil depth reached its corresponding field capacity value. With both irrigation systems, beds were irrigated simultaneously with ridges and with the same irrigation duration. Plants from

  2. Propagation of biases in humidity in the estimation of global irrigation water

    NASA Astrophysics Data System (ADS)

    Masaki, Y.; Hanasaki, N.; Takahashi, K.; Hijioka, Y.

    2015-07-01

    Future projections on irrigation water under a changing climate are highly dependent on meteorological data derived from general circulation models (GCMs). Since climate projections include biases, bias correction is widely used to adjust meteorological elements, such as the atmospheric temperature and precipitation, but less attention has been paid to biases in humidity. Hence, in many cases, uncorrected humidity data have been directly used to analyze the impact of future climate change. In this study, we examined how the biases remaining in the humidity data of five GCMs propagate into the estimation of irrigation water demand and consumption from rivers using the global hydrological model (GHM) H08. First, to determine the effects of humidity bias across GCMs, we ran H08 with GCM-based meteorological forcing data sets distributed by the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP). A state-of-the-art bias correction method was applied to the data sets without correcting biases in humidity. Differences in the monthly relative humidity amounted to 11.7 to 20.4 % RH (percentage relative humidity) across the GCMs and propagated into differences in the estimated irrigation water demand, resulting in a range between 1152.6 and 1435.5 km3 yr-1 for 1971-2000. Differences in humidity also propagated into future projections. Second, sensitivity analysis with hypothetical humidity biases of ±5 % RH added homogeneously worldwide revealed the large negative sensitivity of irrigation water abstraction in India and East China, which are heavily irrigated. Third, we performed another set of simulations with bias-corrected humidity data to examine whether bias correction of the humidity can reduce uncertainties in irrigation water across the GCMs. The results showed that bias correction, even with a primitive methodology that only adjusts the monthly climatological relative humidity, helped reduce uncertainties across the GCMs: by using bias-corrected humidity

  3. Using Satellite-based Evapotranspiration Estimation to Characterize Agricultural Irrigation Water Use

    NASA Astrophysics Data System (ADS)

    Zheng, B.; Myint, S. W.; Hendrickx, J. M. H.

    2014-12-01

    The satellite-based evapotranspiration (ET) model permits estimation of water consumption across space and time in a systematic way. Developing tools to monitor water availability and water use is critical to meet future water shortage challenges in the American West. This study applied METRIC (Mapping Evapotranspiration at high Resolution and with Internalized Calibration) to 2001 Landsat imagery to estimate ET of various crop types in Phoenix. The total annual ET estimates are correlated well with the actual water use at the irrigation district level (r=0.99). We further incorporated a crop type map to estimate annual ET for the major crop types in the region, and to examine variability in crop water use among different irrigation districts. Our results show that alfalfa and double crops consume more water than other crop types with mean annual ET estimations of 1300 to 1580 mm/year, and that cotton uses more water (1162 mm/year) than corn (838 mm/year) and sorghum (829 mm/year) as expected. Crop water use varies from one irrigation district to another due to differences in soil quality, water quality, and farming practices. Results from our study suggest that the ET maps derived from METRIC can be used to quantify the spatial distribution of ET and to characterize agricultural water use by crop types at different spatial scales.

  4. Water balance and soil losses in an irrigated catchment under conservation tillage in Southern Spain

    NASA Astrophysics Data System (ADS)

    Cid, Patricio; Mateos, Luciano; Taguas, Encarnación V.; Gómez-Macpherson, Helena

    2013-04-01

    Conservation tillage based on permanent beds with crop-residue retention and controlled traffic has been recently introduced in irrigated annual crops in Southern Spain as one way to improve water infiltration, reduce soil losses, and save energy. The water balance and soil losses in water runoff have been monitored during 4 years in a 28-ha catchment within a production farm where this kind of soil conservation practice was established in 2004 for a maize-cotton-wheat rotation. The catchment average slope is 6 %. Soils are Typic Calcixerept and Typic Haploxerert. The water balance components that were measured include: applied irrigation water, rainfall, and runoff. Runoff was measured at the outlet of the catchment by means of a hydrological station that consisted of long-throated flume, ultrasonic water level sensor, automatic water sampler, data logger and transmission system, weather station, and ancillary equipment. We present here results from three hydrological seasons (October to September): 2009-10, 2010-11, and 2011-12. The first season the catchment was grown with wheat, thus the irrigation depth was small (25 mm); rainfall above average, 1103 mm; and the runoff coefficient was 26 %. In the season 2010-11, the catchment was grown with cotton, the irrigation depth was 503 mm, rainfall was 999 mm, and the seasonal runoff coefficient was 7 %. The last season, the crop was maize, rainfall was below average (368 mm), irrigation 590 mm, and the runoff coefficient as the previous year, 7 %. Soil losses were very small: 0.05, 1.26, and 1.33 t per ha and year, the first, second, and third monitored seasons, respectively. A simple water balance model allowed simulating evapotranspiration, deep percolation and runoff. The Curve Number for the catchment was calibrated using the balance model.

  5. How Will Climate Change Impact Water Consumption for Rice Irrigation in Southern Brazil?

    NASA Astrophysics Data System (ADS)

    dos Santos, T. V.; Twine, T. E.

    2015-12-01

    Globally, agricultural water use accounts for most of the water that is withdrawn from surface water and groundwater. Rice, one of the world's leading food crops, requires that fields be continuously flooded to obtain optimal yields. High air temperature and consecutive rainless days in rice-growing areas can significantly reduce rice yields, leading to food scarcity. Climate change is expected to affect water demand for rice via changes in rainfall regime, soil water balance, and evapotranspiration. Higher temperatures and increased variability of precipitation are predicted to increase water demand and could potentially require more irrigation in lowland rice-growing areas. In this study we present the first results from model simulations in which we integrated a rice model into the Agro-IBIS dynamic ecosystem model. We predict the impact of climate change on the water use requirement of rice production in southern Brazil and evaluate changes in irrigation needed to meet minimum water demand to sustain current yields. Brazil is the 9th top rice producer in the world, and southern Brazil accounts for about 80% of the national production. The Agro-IBIS model was driven with historic weather data provided by CRU (1961-90) and with two future climate scenarios from the Coupled Model Intercomparison Project Phase 5 (CMIP5) for 2015-2100 - Representative Concentration Pathways 4.5 (RCP45) and 8.5 (RCP85). On an hourly time step, Agro-IBIS accounts for gains (precipitation) and losses (evaporation, transpiration, infiltration and runoff) of water in each grid cell, and uses rules to irrigate in order to maintain a specific height of standing water on the field. Simulated historic and future amounts of irrigated water needed to maintain this water height will be evaluated to predict future water demand for rice production in southern Brazil.

  6. The use of zero-valent iron filtration to reduce Escherichia coli and Listeria innocua in irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Irrigation water can be a source of contamination in outbreaks associated with produce. Zero-valent iron (ZVI) filtration has been effective in E. coli O157:H12 in irrigation water, but has not been evaluated against Listeria spp. Purpose: To 1) determine effectiveness of ZVI filters...

  7. Quality of shallow groundwater and drainage water in irrigated agricultural lands in a Mediterranean coastal region of Turkey.

    PubMed

    Odemiş, Berkant; Bozkurt, Sefer; Ağca, Necat; Yalçin, Mehmet

    2006-04-01

    Spatial and seasonal differences in water quality of drainage water and unconfined shallow groundwater were related to irrigation in Samandağ, a Mediterranean coastal region. Eighteen wells, seven drainage points and Orontes River were monitored bimonthly for one year for analyses of electrical conductivity (EC), total dissolved solids (TDS), sodium adsorption ratio (SAR), cations (Na, K, Ca + Mg) and anions (CO(3), HCO(3), Cl and SO(4)). Agricultural irrigation using saline groundwater decreased water quality of Orontes River during the irrigation season (May to September) more than during the non-irrigation season (October to April). Seasonal fluctuations in water quality of shallow groundwater were greater during the irrigation season than the non-irrigation season in the study area. Excessive use of groundwater resulted in a decline in the water table levels in the irrigation season. Water table level rose up to the soil surface in areas where there was a lack of drainage or poor drainage, due to the impact of precipitation in the winter. SAR and pH values of drainage water increased in the irrigation season, while the other properties of drainage water decreased. Irrigation water quality of Orontes River was classified as C(3)S(1) in both seasons. Irrigation water quality of shallow groundwater and drainage water varied from C(2)S(1) to C(4)S(2) in one year. Drainage and well waters were found to be different on yearly basis in terms of Na, SAR (p<0.01) and Ca + Mg concentrations (p<0.001). Ca + Mg concentrations for both sources were different for all sampling dates (p<0.001). PMID:16614781

  8. Using Soil Moisture as a Guide in Controlling the Amount of Irrigated Water on Grass Lawns

    NASA Astrophysics Data System (ADS)

    Boateng, S.; Koenig, J.

    2007-05-01

    Soil moisture content is one of the factors that controls the infiltration capacity of soils. Precipitation and irrigation increase soil moisture which in turn reduces infiltration capacity. This results in increased runoff during subsequent storm events. Increased stormwater runoff may cause adverse environmental problems such as increased soil erosion, increased bed and suspended loads in streams, and increased non-point source pollution. Monitoring soil moisture on irrigated plots can be used as a guide for efficient use of irrigated water. Thus, irrigation systems only will be turned on when soil moisture falls below a threshold value for the respective soil type. However, landscapers at Northern Kentucky University (NKU) schedule the irrigation of grass lawns without taking into consideration the level of soil moisture. This has resulted in incidences of irrigation of the lawns during or immediately after a heavy storm event. Effective monitoring of the soil moisture of irrigated fields has been shown to help in controlling cost of irrigation and conserving valuable resources. This can be achieved by using instruments such as tensiometers and neutron probes to monitor soil moisture (Manning, 1992). On an irrigated field such as a grass lawn, the ideal condition will be to maintain soil moisture between field capacity and wilting point. The objective of this study is to investigate the effect of soil texture and slope on the amount of irrigated water used on selected grass lawns on NKU campus at Highland Heights, Kentucky. The grass lawns were selected based on low slope (0 to 10¬0), medium slope (10¬0 to 15¬0), and high slope (more than 15¬0 ). Two plots were selected for each slope category. The soil texture of each grass lawn was determined by performing standard particle size distribution analysis of samples taken during the installation of the tensiometers. A survey instrument and a GIS software were used to analyze the slopes. The tensiometers were

  9. Carbon Sequestration Potential in Irrigated Agriculture: Greenhouse Gas Emissions and the Contribution of Water.

    NASA Astrophysics Data System (ADS)

    Rolston, D. E.; Hopmans, J. W.; van Kessel, C.; Six, J.; Paw U, K.; Plant, R.; Lee, J.; Kochendorfer, J.; Ideris, A. J.; MacIntyre, J.; Louie, D.; Matista, T.; Evatt, J.; Poch, R.; King, A. P.

    2006-12-01

    This study aimed to quantify CO2 and N2O release from an irrigated field in California's Sacramento Valley in an effort to determine greenhouse gas mitigation potentials through minimum tillage (MT) practices. Surface CO2 and N2O flux were monitored on the 30 ha, laser-leveled field site from September 2003 through August 2006. Additional field-representative flux data was collected from eddy-covariance masts and continuously sampling auto-chambers. Irrigation and run-off waters were collected and analyzed for total suspended solids (TSS), dissolved organic carbon (DOC), dissolved organic nitrogen (DON), nitrate-N, ammonium-N, total C and total N in the sediment. Overall, we found very little difference in CO2 flux, water composition, or sediment composition between the two tillage treatments. N2O flux was negligible in both systems until a fertilization and irrigation event occurred in each growing season, at which point the MT treatment showed slightly higher fluxes. NO3-N levels in the run-off exceeded drinking water quality standards only in irrigation events following fertilizer application. Collected CO2 and N2O data from this site will enable us to predict greenhouse gas emissions from similar agricultural systems in the California landscape. Our results indicate that the role of irrigation water in C budgets of agricultural systems is a significant factor in determining total C sequestration potential, but that short-term MT may not significantly decrease the contribution to global warming by irrigated agroecosystems and thus may not be a beneficial strategy for greenhouse gas mitigation.

  10. Water: pesticides in ground water beneath irrigated farmland in Nebraska, August 1978

    SciTech Connect

    Spalding, R.F.; Junk, G.A.; Richard, J.J.

    1980-09-01

    During the 1978 irrigation season, 14 ground water samples were collected in the Central Platte region of Nebraska, an area known to have high nitrate-nitrogen (NO-N) levels, and analyzed for the presence of 13 pesticide residues. Atrazine levels ranged from 0.06 ..mu..g/liter to 3.12 ..mu..g/liter and were correlated to NO/sub 3/-N concentrations with a coefficient of r = +0.55. Nitrate-nitrogen concentrations were measured as indicators of deep percolation from irrigated lands and ranged from 17.1 mg/liter to 34.3 mg/liter. Alachlor levels ranged from <0.01 ..mu..g/liter to 0.71 ..mu..g/liter. The amounts of 2,4-D were indeterminate because of experimental problems. Levels of the herbicides silvex and EPTC were below the limits of detectability. Levels of the oragnochlorine insecticides endrin, ..gamma..-BHC (lindane), dieldrin, DDT and its primary metabolite DDE, heptachlor and its primary derivative heptachlor epoxide, and methoxychlor were all below the detectable limits of 0.005 and 0.010 ..mu..g/liter.

  11. Effects of furrow irrigation on the growth, production, and water use efficiency of direct sowing rice.

    PubMed

    He, Chunlin

    2010-01-01

    Rice farming is the major crop production in Asia and is predicted to increase significantly in the near future in order to meet the demands for the increasing human population. Traditional irrigation methods used in rice farming often result in great water loss. New water-saving methods are urgently needed to reduce water consumption. Three field and pot experiments were conducted to evaluate the furrow irrigation (FI) system to improve water use efficiency (WUE) and production of direct sowing rice in southern China. Compared to the conventional irrigation (CI) system (continuous flooding irrigation), for every square hectometer of rice field, the FI system reduced water use by 3130 m3, or 48.1%, and increased grain production by 13.9% for an early cultivar. For a late cultivar, the FI system reduced water use by 2655 m3, or 40.6%, and an increase of grain production by 12.1%. The improved WUE in the FI system is attributed to (1) a significant reduction of irrigation rate, seepage, evaporation, and evapotranspiration; (2) a significant reduction in the reduced materials, such as ferrous ion (Fe2+), and therefore an increase in the vitality of the root system, evident by the increases in the number of white roots by 32.62%, and decreases in the number of black roots by 20.04% and yellow roots by 12.58%; the use of the FI system may also reduce humidity of the rice field and enhance gas transport in the soil and light penetration, which led to reduced rice diseases and increased leaf vitality; and (3) increases in tiller and effective spikes by 11.53% and the weight per thousand grains by 1.0 g. These findings suggest that the shallow FI system is a promising means for rice farming in areas with increasing water shortages. PMID:20694444

  12. Irrigation waters and pipe-based biofilms as sources for antibiotic-resistant bacteria.

    PubMed

    Blaustein, Ryan A; Shelton, Daniel R; Van Kessel, Jo Ann S; Karns, Jeffrey S; Stocker, Matthew D; Pachepsky, Yakov A

    2016-01-01

    The presence of antibiotic-resistant bacteria in environmental surface waters has gained recent attention. Wastewater and drinking water distribution systems are known to disseminate antibiotic-resistant bacteria, with the biofilms that form on the inner-surfaces of the pipeline as a hot spot for proliferation and gene exchange. Pipe-based irrigation systems that utilize surface waters may contribute to the dissemination of antibiotic-resistant bacteria in a similar manner. We conducted irrigation events at a perennial stream on a weekly basis for 1 month, and the concentrations of total heterotrophic bacteria, total coliforms, and fecal coliforms, as well as the concentrations of these bacterial groups that were resistant to ampicillin and tetracycline, were monitored at the intake water. Prior to each of the latter three events, residual pipe water was sampled and 6-in. sections of pipeline (coupons) were detached from the system, and biofilm from the inner-wall was removed and analyzed for total protein content and the above bacteria. Isolates of biofilm-associated bacteria were screened for resistance to a panel of seven antibiotics, representing five antibiotic classes. All of the monitored bacteria grew substantially in the residual water between irrigation events, and the biomass of the biofilm steadily increased from week to week. The percentages of biofilm-associated isolates that were resistant to antibiotics on the panel sometimes increased between events. Multiple-drug resistance was observed for all bacterial groups, most often for fecal coliforms, and the distributions of the numbers of antibiotics that the total coliforms and fecal coliforms were resistant to were subject to change from week to week. Results from this study highlight irrigation waters as a potential source for antibiotic-resistant bacteria, which can subsequently become incorporated into and proliferate within irrigation pipe-based biofilms. PMID:26703979

  13. Response of the Rio Grande and shallow ground water in the Mesilla Bolson to irrigation, climate stress, and pumping

    USGS Publications Warehouse

    Walton, J.; Ohlmacher, G.; Utz, D.; Kutianawala, M.

    1999-01-01

    The El Paso-Ciudad Juarez metropolitan area obtains its water from the Rio Grande and intermontane-basin aquifers. Shallow ground water in this region is in close communications with the surface water system. A major problem with both systems is salinity. Upstream usage of the water in the Rio Grande for irrigation and municipalities has led to concentration of soluble salts to the point where the surface water commonly exceeds drinking water standards. Shallow ground water is recharged by surface water (primarily irrigation canals and agricultural fields) and discharges to surface water (agricultural drains) and deeper ground water. The source of water entering the Rio Grande varies seasonally. During the irrigation season, water is released from reservoirs and mixes with the return flow from irrigation drains. During the non-irrigation season (winter), flow is from irrigation drains and river water quality is indicative of shallow ground water. The annual cycle can be ascertained from the inverse correlation between ion concentrations and discharge in the river. Water-quality data indicate that the salinity of shallow ground water increases each year during a drought. Water-management strategies in the region can affect water quality. Increasing the pumping rate of water-supply wells will cause shallow ground water to flow into the deeper aquifers and degrade the water quality. Lining the canals in the irrigation system to stop water leakage will lead to water quality degradation in shallow ground water and, eventually, deep ground water by removing a major source of high quality recharge that currently lowers the salinity of the shallow ground water.

  14. Reduction of predictive uncertainty in estimating irrigation water requirement through multi-model ensembles and ensemble averaging

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Exbrayat, J.-F.; Kirby, M.; Viney, N. R.; Frede, H.-G.; Breuer, L.

    2015-04-01

    Irrigation agriculture plays an increasingly important role in food supply. Many evapotranspiration models are used today to estimate the water demand for irrigation. They consider different stages of crop growth by empirical crop coefficients to adapt evapotranspiration throughout the vegetation period. We investigate the importance of the model structural versus model parametric uncertainty for irrigation simulations by considering six evapotranspiration models and five crop coefficient sets to estimate irrigation water requirements for growing wheat in the Murray-Darling Basin, Australia. The study is carried out using the spatial decision support system SPARE:WATER. We find that structural model uncertainty among reference ET is far more important than model parametric uncertainty introduced by crop coefficients. These crop coefficients are used to estimate irrigation water requirement following the single crop coefficient approach. Using the reliability ensemble averaging (REA) technique, we are able to reduce the overall predictive model uncertainty by more than 10%. The exceedance probability curve of irrigation water requirements shows that a certain threshold, e.g. an irrigation water limit due to water right of 400 mm, would be less frequently exceeded in case of the REA ensemble average (45%) in comparison to the equally weighted ensemble average (66%). We conclude that multi-model ensemble predictions and sophisticated model averaging techniques are helpful in predicting irrigation demand and provide relevant information for decision making.

  15. Reduction of predictive uncertainty in estimating irrigation water requirement through multi-model ensembles and ensemble averaging

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Exbrayat, J.-F.; Kirby, M.; Viney, N. R.; Frede, H.-G.; Breuer, L.

    2014-11-01

    Irrigation agriculture plays an increasingly important role in food supply. Many evapotranspiration models are used today to estimate the water demand for irrigation. They consider different stages of crop growth by empirical crop coefficients to adapt evapotranspiration throughout the vegetation period. We investigate the importance of the model structural vs. model parametric uncertainty for irrigation simulations by considering six evapotranspiration models and five crop coefficient sets to estimate irrigation water requirements for growing wheat in the Murray-Darling Basin, Australia. The study is carried out using the spatial decision support system SPARE:WATER. We find that structural model uncertainty is far more important than model parametric uncertainty to estimate irrigation water requirement. Using the Reliability Ensemble Averaging (REA) technique, we are able to reduce the overall predictive model uncertainty by more than 10%. The exceedance probability curve of irrigation water requirements shows that a certain threshold, e.g. an irrigation water limit due to water right of 400 mm, would be less frequently exceeded in case of the REA ensemble average (45%) in comparison to the equally weighted ensemble average (66%). We conclude that multi-model ensemble predictions and sophisticated model averaging techniques are helpful in predicting irrigation demand and provide relevant information for decision making.

  16. The Role of Windbreaks in Reducing Water Resources Use in Irrigated Agriculture

    NASA Astrophysics Data System (ADS)

    Cochrane, T. A.; de Vries, T. T.

    2014-12-01

    Windbreaks are common features in flat agricultural landscapes around the world. The reduction in wind speed afforded by windbreaks is dictated by their porosity, location, height, and distance from the windbreak. The reduction in wind speeds not only reduces potential wind erosion; it also reduces crop evapotranspiration (ET) and provides shelter for livestock and crops. In the Canterbury plains of New Zealand there are over 300,000 km of windbreaks which were first implemented as a soil conservation strategy to reduce wind erosion of prime agricultural land. Agriculture in the region has since changed to irrigated pasture cultivation for dairy production and windbreaks are being cut down or reduced to heights of 2 m to allow for large scale centre-pivot irrigation schemes. Although soil erosion is no longer a major concern due to permanent pasture cover, irrigation water is sourced from limited supplies of ground and surface water and thus the effects of wind on irrigation losses due to spray drift and increased ET are of significant concern. The impact of reducing windbreaks needs to be understood in terms of water resources use. Experimental and theoretical work was conducted to quantify the reduction in wind speeds by windbreaks and in spray evaporation losses. A temporal and spatial model was also developed and validated to quantify the impact of single and multiple windbreaks on irrigation water losses. Initial modelling results show that for hot windy dry conditions in Canterbury, ET can increase by up to 1.4 mm/day when windbreaks are reduced to 2 m in height and on average wind days ET can increase by up to 0.5 mm/day. ET can be reduced by up to 30% in the windbreak leeward zone relative to ET in areas not protected by windbreaks. Wind speed, air temperature and relative humidity all had a considerable impact on spray evaporation losses, but the extent is determined by the droplet size. Estimated losses range from only 0.07% to 67% for 5 and 0.2 mm

  17. Quantifying Irrigation Return Flows Using Stable Isotopes of Water along the South Platte River, Colorado USA

    NASA Astrophysics Data System (ADS)

    Sanford, W. E.; Davila Olmo, K.; Stednick, J. D.

    2011-12-01

    As the South Platte River flows from Denver, CO to the Nebraska border it crosses urban and agricultural settings which affect water quality and quantity. This reach of the river is highly regulated, with numerous diversions, off-channel reservoirs, and flow-augmentation projects. Water in the river is used 7 different times between Denver and the state line. Much of the water diverted from the river is used for irrigation. A significant portion of this water returns to the river as groundwater flow, often during times of low stream flow. Groundwater return flows, coupled with wastewater treatment plant and reservoir storage, have turned the once ephemeral river into a perennial one. The goal of this research was to determine if the stable isotopes of water (δ 2H and δ18O) in the river can be used to identify and to help quantify groundwater return flows to the river. Water samples were collected and analyzed for their isotopic signature at 17 sites from Denver to Julesburg. Nine rounds of samples were collected from June 2009 to June 2010. Well defined linear patterns of isotope ratios are observed on individual sampling events indicating that the water in the river is becoming enriched as it moves downstream. The enrichment is caused by evaporation from irrigation waters and their discharge to the river as groundwater return flows. These promising results indicate that it may be possible to quantify irrigation return flow to the South Platte River using the stable isotopes of water.

  18. The use of zero-valent iron and biosand filtration to inactivate Escherichia coli O157:H7 in irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Foodborne pathogens can be disseminated to produce through contaminated irrigation water. Effective, low cost mitigation strategies, like biosand and zero-valent iron (ZVI) filtration, may be effective in decontaminating irrigation water. Purpose: To determine the effectiveness ...

  19. Improved ant colony optimization for optimal crop and irrigation water allocation by incorporating domain knowledge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An improved ant colony optimization (ACO) formulation for the allocation of crops and water to different irrigation areas is developed. The formulation enables dynamic adjustment of decision variable options and makes use of visibility factors (VFs, the domain knowledge that can be used to identify ...

  20. Yield and ion relations of alfalfa (Medicago sativa L.) in response to irrigation with saline waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a major forage crop utilized in arid and semi-arid regions under irrigation; these regions are commonly impacted by saline water and soils. Four commercial non-dormant, purported salt tolerant Alfalfa cultivars 'Salado', 'S&W8421s', 'S&W9720' and 'S&W9215' were grown in 24 outdoor sand ta...

  1. RESEARCH NEEDS TO SUSTAIN AGRICULTURE ON THE HIGH PLAINS WITH LIMITED IRRIGATION WATER SUPPLIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigated agriculture in the West is facing declining water supplies. Many aquifers are being pumped at non-sustainable rates. Increasing realization of the inter-connectivity of surface and groundwater supplies are resulting in legal restrictions on groundwater use. Downstream (or upstream) user...

  2. Directed manipulation of crop water status through canopy temperature-based irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While the relationship between canopy temperature and plant water status is well established, canopy temperature as a means of controlling crop irrigation has been limited in production applications due to the cost and complexity of temperature monitoring. A new low-cost infrared thermometry system...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  4. Predicting perchlorate uptake in greenhouse lettuce from perchlorate, nitrate and chloride irrigation water concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perchlorate (ClO4-) has been detected in edible leafy vegetables irrigated with Colorado River water. The primary concern has been the ClO4- concentration in lettuce. There has been a limited number of studies on ClO4- uptake but the interactive effect of other anions on ClO4- uptake is not known in...

  5. Camelina water use and seed yield response to irrigation scheduling in an arid environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Camelina sativa (L.) Crantz is a promising, biodiesel-producing oilseed that could potentially be implemented as a low-input alternative crop for production in the arid southwestern USA. However, little is known about camelina’s water use, irrigation management, and agronomic characteristics in this...

  6. Evaluating irrigation management strategies to maximize cotton yield and water use efficiency: A simulation analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing pumping costs and declining well capacities in the Texas High Plains compel producers to adapt irrigation strategies for maximum crop yield and water use efficiency (WUE)(ratio yield to evapotranspiration, ET), using applications that vary between none (i.e., dryland production) and compl...

  7. Cotton production potential and water conservation impact using the regional irrigation demand model of northern Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Revised irrigation demands are calculated for the 21 northernmost counties in Texas, identified as Panhandle Region (also known as Region A), using the TAMA (Texas A&M–Amarillo) agricultural water use demand estimation model. Year 2000 demands are presented using the existing mixture of crops, aver...

  8. The Water Use of Cotton Irrigated with Sub-Sruface Drip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Texas High Plains (THP), producers are constantly searching for water conservation methods. With a semiarid climate, declining aquifer levels and negligible aquifer recharge, the use of subsurface drip irrigation (SDI) is therefore increasing each year. However, information on the best manage...

  9. Deficit irrigation: Arriving at the crop water stress index via gas exchange measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant gas exchange provides a highly sensitive measure of the degree of drought stress. Canopy temperature (Tc) provides a much easier to acquire indication of crop water deficit that has been used in irrigation scheduling systems, but interpretation of this measurement has proven difficult. Our goa...

  10. Uptake and distribution of bisphenol A and nonylphenol in vegetable crops irrigated with reclaimed water.

    PubMed

    Lu, Jian; Wu, Jun; Stoffella, Peter J; Wilson, P Chris

    2015-01-01

    The potential uptake and distribution of bisphenol A (BPA) and nonylphenol (NP) (from reclaimed irrigation water) in edible crops was investigated. BPA and NP were spiked into simulated reclaimed water at environmentally relevant concentrations. Two crops (lettuce, Lactuca sativa and tomato, Lycopersicon esculentum) were grown hydroponically in a greenhouse using the spiked irrigation water under two irrigation exposure scenarios (overhead foliar exposure and subsurface root exposure). BPA concentrations in tomato fruit were 26.6 ± 5.8 (root exposure) and 18.3 ± 3.5 (foliar exposure) μg kg(-1), while concentrations in lettuce leaves were 80.6 ± 23.1 (root exposure) and 128.9 ± 17.4 (foliar exposure) μg kg(-1). NP concentrations in tomato fruit were 46.1 ± 6.6 (root exposure) and 24.6 ± 6.4 (foliar exposure) μg kg(-1), while concentrations in lettuce leaves were 144.1 ± 9.2 (root exposure) and 195.0 ± 16.9 (foliar exposure) μg kg(-1). BPA was relatively mobile in lettuce plants regardless of exposure route. Limited mobility was observed for NP in both crops and BPA in tomatoes. The estimated daily intake of BPA and NP through consumption of vegetables irrigated with reclaimed water ranged from 8.9-62.9 to 11.9-95.1 μg, respectively, depending on the exposure route. PMID:25464330

  11. Uncertainty analysis of an irrigation scheduling model for water management in crop production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation scheduling tools are critical to allow producers to manage water resources for crop production in an accurate and timely manner. To be useful, these tools need to be accurate, complete, and relatively reliable. The current work presents the uncertainty analysis and its results for the Mis...

  12. Water productivity, yield, and berry composition in sustained versus regulated deficit irrigation of Merlot grapevines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wine grape cultivar Merlot (Vitis vinifera L.) was irrigated at incremental fractions of estimated crop evapotranspiration or a regulated deficit (RDI) regime to identify which practice best optimized water productivity and berry composition without compromising yield. Three severities of susta...

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

    PubMed

    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. PMID:24682661

  14. Results of an irrigated lands assessment for water management in California

    NASA Technical Reports Server (NTRS)

    Bauer, E. H.; Baggett, J. D.; Wall, S. L.; Thomas, R. W.; Brown, C. E.

    1984-01-01

    Periodic assessment of existing and future demands for water within California is one responsibility of the California Department of Water Resources (CDWR). The California Irrigated Lands Assessment for Water Management Project represented a 5-year joint research effort between the NASA and the CDWR with technical support from the University of California (UC) at Berkeley and at Santa Barbara. The objectives were: (1) to develop and demonstrate procedures for providing highly precise, timely, estimates of irrigated area on a statewide basis using Landsat sensor data, and (2) to develop, through research with small demonstration sites, a procedure for the inventory and mapping of crop groups on a regional basis. Both manual and computer-assisted analyses were investigated. This paper highlights the statewide irrigated lands inventory where a procedure for statewide estimation of irrigated land using full frame Landsat MSS imagery and sampled ground data was successfully demonstrated. The statewide estimate of 3 990 112 hectares was within + or - 1.32 percent relative standard error at the 95-percent Confidence Interval, well within the design goal. This procedure represents a new capability for obtaining near-real time data on changes in agricultural water use throughout the state.

  15. Residue management effects on water use and yield of deficit irrigated corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Storing precipitation as soil water during crop-rotation fallow periods may offset decreasing irrigation well capacity that is caused by the declining accessible groundwater of the Ogallala Aquifer in the Southern High Plains. A three year dryland rotation that produces crops of wheat (Triticum aest...

  16. Cotton Water Use Efficiency Under Two Different Deficit Irrigation Scheduling Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Declines in Ogallala aquifer levels used for irrigation has prompted research to identify methods for optimizing water use efficiency (WUE) of cotton (Gossypium hirsutum L). In this experiment, conducted at Lubbock, Texas in 2014, our objective was to test two canopy temperature based stress indices...

  17. Leaching of pharmaceuticals and personal care products in turfgrass soils during recycled water irrigation.

    PubMed

    Bondarenko, S; Gan, J; Ernst, F; Green, R; Baird, J; McCullough, M

    2012-01-01

    An important beneficial reuse of treated wastewater (recycled water) in arid and semiarid regions is landscape irrigation. However, the environmental fate, especially groundwater contamination potential, of trace contaminants such as pharmaceuticals and personal care products (PPCPs) is a significant concern that can hinder the acceptance and adoption of such reuses. In this study, we irrigated mature turfgrass plots with nonspiked tertiary treated wastewater for over 6 mo at 100 or 130% of the reference evapotranspiration rate (ETo) and collected leachate water at the 90-cm depth on a weekly basis. In the recycled water, all 14 target PPCPs were consistently found, and the mean levels of atenolol, gemfibrozil, meprobamate, carbamazepine, and sulfamethoxazole were above 100 ng L. However, only five compounds were detected in the leachate at trace levels. Trimethoprim and primidone were frequently found, whereas the detection of sulfamethoxazole, meprobamate and carbamazepine was less frequent (<50%). When detected, the overall mean concentration in the leachate was 10.2 ng L for trimethoprim, 7.1 ng L for primidone, and 2.9 to 12.4 ng L for carbamazepine, sulfamethoxazole, and meprobamate. The majority of the target PPCPs were completely removed. Given that the irrigation rates were higher than normal, this study clearly demonstrated the efficacy of turfgrass systems in attenuating PPCPs during recycled water irrigation. However, it is also apparent that some PPCPs are more susceptible to leaching than others, and these PPCPs thus merit further research attention. PMID:22751071

  18. In-Soil and Down-Hole Soil Water Sensors: Characteristics for Irrigation Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The past use of soil water sensors for irrigation management was variously hampered by high cost, onerous regulations in the case of the neutron probe (NP), difficulty of installation or maintenance, and poor accuracy. Although many sensors are now available, questions of their utility still abound....

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. Reclaimed water as a reservoir of antibiotic resistance genes: distribution system and irrigation implications.

    PubMed

    Fahrenfeld, Nicole; Ma, Yanjun; O'Brien, Maureen; Pruden, Amy

    2013-01-01

    Treated wastewater is increasingly being reused to achieve sustainable water management in arid regions. The objective of this study was to quantify the distribution of antibiotic resistance genes (ARGs) in recycled water, particularly after it has passed through the distribution system, and to consider point-of-use implications for soil irrigation. Three separate reclaimed wastewater distribution systems in the western U.S. were examined. Quantitative polymerase chain reaction (qPCR) was used to quantify ARGs corresponding to resistance to sulfonamides (sul1, sul2), macrolides (ermF), tetracycline [tet(A), tet(O)], glycopeptides (vanA), and methicillin (mecA), in addition to genes present in waterborne pathogens Legionella pneumophila (Lmip), Escherichia coli (gadAB), and Pseudomonas aeruginosa (ecfx, gyrB). In a parallel lab study, the effect of irrigating an agricultural soil with secondary, chlorinated, or dechlorinated wastewater effluent was examined in batch microcosms. A broader range of ARGs were detected after the reclaimed water passed through the distribution systems, highlighting the importance of considering bacterial re-growth and the overall water quality at the point of use (POU). Screening for pathogens with qPCR indicated presence of Lmip and gadAB genes, but not ecfx or gyrB. In the lab study, chlorination was observed to reduce 16S rRNA and sul2 gene copies in the wastewater effluent, while dechlorination had no apparent effect. ARGs levels did not change with time in soil slurries incubated after a single irrigation event with any of the effluents. However, when irrigated repeatedly with secondary wastewater effluent (not chlorinated or dechlorinated), elevated levels of sul1 and sul2 were observed. This study suggests that reclaimed water may be an important reservoir of ARGs, especially at the POU, and that attention should be directed toward the fate of ARGs in irrigation water and the implications for human health. PMID:23755046

  1. Effects of seedbed preparation, irrigation, and water harvesting of seedling emergence at the Nevada Test Site

    SciTech Connect

    Winkel, V.K.; Ostler, W.K.; Gabbert, W.D.; Lyon, G.E.

    1994-02-01

    Approximately 800 hectares on the US Department of Energy Nevada Test Site and vicinity are contaminated with plutonium. As part of a cleanup effort, both the indigenous vegetation and the top 5--10 cm of soil may be removed, and the soil may or may not be replaced. Technologies must be developed to stabilize and revegetate these lands. A study was developed to determine adaptable plant species, methods to prepare seedbeds for direct seeding and water harvesting, and proper irrigation rates. Plots were cleared of indigenous vegetation, and then prepared with various seedbed/water harvesting treatments including, pitting, land imprinting, and mulching. Other plots were treated with large water harvesting structures. Three irrigation treatments were superimposed over the seedbed/water harvesting treatments. Seedling emergence data was collected, and the treatment combinations compared. Supporting meteorological and soil data were collected with an automatic data-logger. Specific data included precipitation, and air temperature. In a year of above-average precipitation, irrigation did not generally aid germination and emergence of seeded species, and only slightly increased densities of species from the native seedbank. With the exception of increased shrub seedling densities in desert strips, there were no strong seedbed preparation/water harvesting treatment effects. In years of above-average rainfall, mulching and water harvesting treatments, irrigation may not be necessary to insure adequate germination and emergence of adapted perennial grasses, forbs, and shrubs in the Mojave/Great Basin Transition Desert. Future collection of survival data will determine whether a maintenance irrigation program is necessary to ensure establishmnent of native plants.

  2. Grey water treatment at a sports centre for reuse in irrigation: a case study.

    PubMed

    Gabarró, J; Batchelli, L; Balaguer, M D; Puig, S; Colprim, J

    2013-01-01

    Grey water has long been considered a promising option for dealing with water scarcity and reuse. However, factors such as lack of macronutrients and low carbon content make its treatment challenging. The aim of this paper was to investigate the applicability of sequencing batch reactor (SBR) technology to on-site grey water treatment at a sports centre for reuse in irrigation. The results demonstrated that the regenerated water complied with microbiological parameters concerning restriction of solids and organic matter removal. Denitrification was not fully accomplished, but ammonium was totally oxidised and low concentrations of nitrates were achieved. Effluent with good appearance and no odour was used in an experimental study to irrigate a grid system containing natural and artificial grass sections. The conclusion is that SBR technology offers a promising treatment for grey water. PMID:24191471

  3. Impacts of Change in Irrigation Water Availability on Food Production in the Yellow River Basin under Climate Change

    NASA Astrophysics Data System (ADS)

    Yin, Y. Y.; Tang, Q.

    2014-12-01

    Approximately 9 percent of China's population and 17 percent of its agricultural area are settled in the Yellow River Basins. Irrigation, which plays an important role in agricultural production, occupies the largest share of human consumptive water use in the basin. Given increasing water demands, the basin faces acute water scarcity. Previous studies have suggested that decrease in irrigation water availability under climate change might have an overall adverse impact on the food production of the basin. The timing and area that would face severe water stress are yet to be identified. We used a land surface hydrological model forced with the bias-corrected climatic variables from 5 climate models under 4 Representative Concentration Pathways (RCPs) to estimate total water availability in the sub-basins of the Yellow River basin. The future socioeconomic conditions, the Shared Socioeconomic Pathways (SSPs), were used to estimate the water requirement in the nonagricultural water use sectors. The irrigation water availability was estimated from the total water availability and nonagricultural water use, and the irrigation water demands were estimated based on the current irrigation project efficiencies. The timing and area of irrigation water shortage were shown and the implication of change in irrigation water availability on food production was assessed. The results show that the sub-basins with high population density and gross domestic product (GDP) are likely to confront severe water stress and reduction in food production earlier because irrigation water was to be appropriated by the rapid increase in nonagricultural water use sectors. The study stresses the need for adaptive management of water to balance agriculture and nonagricultural demands in northern China.

  4. Management of water for irrigation agriculture in semi-arid areas: Problems and prospects

    NASA Astrophysics Data System (ADS)

    Mvungi, A.; Mashauri, D.; Madulu, N. F.

    Most of the Mwanga district is classified as semi-arid with a rainfall range of 300 and 600 mm. Rainfall patterns in the district are unpredictable and are subject to great fluctuations. Like other semi-arid areas, the district is characterized with land degradation, unreliable rainfall, repeated water shortage, periodic famine, overgrazing, dry land cultivation in the marginal areas and heavy competition for limited biomass between farmers and cattle. Vulnerability here is high due to unreliability of weather. The people of Mwanga are dependent on agriculture for their livelihood. However agriculture is difficult in the area due to inadequate rainfall. For a very long time the people have been dependent on irrigation agriculture to ensure food security. Of late the traditional irrigation system is on the decline threatening food security in the area. This paper examines the state and status of the irrigation canal system in Mwanga district with the view of recommending ways in which it can be improved. The study used participatory, survey and in-depth interviews to obtain both quantitative and qualitative data. The major findings are that social, political, environmental and demographic bases that supported the traditional irrigation system have changed drastically. As a corollary to this, the cultural and religious belief systems that supported and guided the traditional canal system management have been replaced by mistrust and corruption in water allocation. In addition the ownership and management system of the water resources that was vested in the initiator clans has changed and now water user groups own the canals/furrows but they do not own the water sources. This has rendered the control of the water sources difficult if not impossible. Currently the system is faced by a number of problems including shortage of water and poor management as demand for water increases and this has led to serious conflicts among and between crop producers and pastoralists

  5. Observation and Modelling of Soil Water Content Towards Improved Performance Indicators of Large Irrigation Schemes

    NASA Astrophysics Data System (ADS)

    Labbassi, Kamal; Akdim, Nadia; Alfieri, Silvia Maria; Menenti, Massimo

    2014-05-01

    Irrigation performance may be evaluated for different objectives such as equity, adequacy, or effectiveness. We are using two performance indicators: IP2 measures the consistency of the allocation of the irrigation water with gross Crop Water requirements, while IP3 measures the effectiveness of irrigation by evaluating the increase in crop transpiration between the case of no irrigation and the case of different levels of irrigation. To evaluate IP3 we need to calculate the soil water balance for the two cases. We have developed a system based on the hydrological model SWAP (Soil Water atmosphere Plant) to calculate spatial and temporal patterns of crop transpiration T(x, y, t) and of the vertical distribution of soil water content θ(x, y, z, t). On one hand, in the absence of ground measurement of soil water content to validate and evaluate the precision of the estimated one, a possibility would be to use satellite retrievals of top soil water content, such as the data to be provided by SMAP. On the other hand, to calculate IP3 we need root zone rather than top soil water content. In principle, we could use the model SWAP to establish a relationship between the top soil and root zone water content. Such relationship could be a simple empirical one or a data assimilation procedure. In our study area (Doukkala- Morocco) we have assessed the consistency of the water allocation with the actual irrigated area and crop water requirements (CWR) by using a combination of multispectral satellite image time series (i,e RapidEye (REIS), SPOT4 (HRVIR1) and Landsat 8 (OLI) images acquired during the 2012/2013 agricultural season). To obtain IP2 (x, y, t) we need to determine ETc (x, y, t). We have applied two (semi)empirical approaches: the first one is the Kc-NDVI method, based on the correlation between the Near Difference Vegetation Index (NDVI) and the value of crop coefficient (kc); the second one is the analytical approach based on the direct application of Penman

  6. Are small-scale irrigators water use efficient? Evidence from lake Naivasha basin, Kenya.

    PubMed

    Njiraini, Georgina W; Guthiga, Paul M

    2013-11-01

    With increasing water scarcity and competing uses and users, water use efficiency is becoming increasingly important in many parts of developing countries. The lake Naivasha basin has an array of different water users and uses ranging from large scale export market agriculture, urban domestic water users to small holder farmers. The small scale farmers are located in the upper catchment areas and form the bulk of the users in terms of area and population. This study used farm household data to explore the overall technical efficiency, irrigation water use efficiency and establish the factors influencing water use efficiency among small scale farmers in the Lake Naivasha basin in Kenya. Data envelopment analysis, general algebraic and modeling system, and Tobit regression methods were used in analyzing cross sectional data from a sample of 201 small scale irrigation farmers in the lake Naivasha basin. The results showed that on average, the farmers achieved only 63 % technical efficiency and 31 % water use efficiency. This revealed that substantial inefficiencies occurred in farming operations among the sampled farmers. To improve water use efficiency, the study recommends that more emphasis be put on orienting farmers toward appropriate choice of irrigation technologies, appropriate choice of crop combinations in their farms, and the attainment of desirable levels of farm fragmentation. PMID:23954914

  7. Are Small-Scale Irrigators Water Use Efficient? Evidence from Lake Naivasha Basin, Kenya

    NASA Astrophysics Data System (ADS)

    Njiraini, Georgina W.; Guthiga, Paul M.

    2013-11-01

    With increasing water scarcity and competing uses and users, water use efficiency is becoming increasingly important in many parts of developing countries. The lake Naivasha basin has an array of different water users and uses ranging from large scale export market agriculture, urban domestic water users to small holder farmers. The small scale farmers are located in the upper catchment areas and form the bulk of the users in terms of area and population. This study used farm household data to explore the overall technical efficiency, irrigation water use efficiency and establish the factors influencing water use efficiency among small scale farmers in the Lake Naivasha basin in Kenya. Data envelopment analysis, general algebraic and modeling system, and Tobit regression methods were used in analyzing cross sectional data from a sample of 201 small scale irrigation farmers in the lake Naivasha basin. The results showed that on average, the farmers achieved only 63 % technical efficiency and 31 % water use efficiency. This revealed that substantial inefficiencies occurred in farming operations among the sampled farmers. To improve water use efficiency, the study recommends that more emphasis be put on orienting farmers toward appropriate choice of irrigation technologies, appropriate choice of crop combinations in their farms, and the attainment of desirable levels of farm fragmentation.

  8. Estimating irrigation water use and withdrawal of ground water on the High Plains, U.S.A.

    NASA Astrophysics Data System (ADS)

    Wray, James R.

    In four decades following the Dust Bowl days of the 1930's, extensive areas of dry farming and rangeland on the semi-arid U.S. High Plains were transformed into a vast region of irrigated oases, producing meat and grain for much of the world. The agricultural economy has experienced such rapid growth in part because of the availability of ground water and because of development of new irrigation technology to use that water for agriculture. However, more water is being used than is being replaced. To estimate both the volume of water withdrawn and the regional scope of the problem a technique has been developed that combines multispectral data from Earth-orbiting satellite with known pumpage data for the same growing season. The location and extent of irrigated cropland-some with different crops watered at different times-is inventoried using computer-assisted analysis of the data from Landsat. The amount of water used is estimated by multiplying and summing surface area of irrigated agriculture and the average measured pumpage from sampled sites. Published findings to date are cited in the Selected References. All suggest transferability of a promising technology to the study of land transformation processes elsewhere.

  9. Estimating irrigation water use and withdrawal of ground water on the High Plains, U.S.A.

    USGS Publications Warehouse

    Wray, J.R.

    1982-01-01

    In four decades following the Dust Bowl days of the 1930's, extensive areas of dry farming and rangeland on the semi-arid U.S. High Plains were transformed into a vast region of irrigated oases, producing meat and grain for much of the world. The agricultural economy has experienced such rapid growth in part because of the availability of ground water and because of development of new irrigation technology to use that water for agriculture. However, more water is being used than is being replaced. To estimate both the volume of water withdrawn and the regional scope of the problem a technique has been developed that combines multispectral data from Earth-orbiting satellite with known pumpage data for the same growing season. The location and extent of irrigated cropland-some with different crops watered at different times-is inventoried using computer-assisted analysis of the data from Landsat. The amount of water used is estimated by multiplying and summing surface area of irrigated agriculture and the average measured pumpage from sampled sites. Published findings to date are cited in the Selected References. All suggest transferability of a promising technology to the study of land transformation processes elsewhere. ?? 1983.

  10. STUDY TO DECREASE TN LOAD AT THE AREA AROUND THE ASHIGAIKE REGULATING RESERVOIR WHERE IRRIGATION WATER IS CONVEYED

    NASA Astrophysics Data System (ADS)

    Namihira, Atsushi; Takaki, Kyoji; Mukai, Akie; Taruya, Hiroyuki

    In the Ashigaike Regulating Reservoir, not the runoff from the watershed but the conveyed water from the outside of watershed is stored for the improvement of the water quality and the strengthening of the irrigation water supply ability. In this reserch, the method not only to decrease TN load but also to preserve the effect of dilution by water conveyance was considered by simulation using distributed water quality tank model. As a results, it was clarified that the following methods are suitable; 1)Water conveyance would not be executed until the storing rate of the reservoir decreases an appropriate value. 2)The runoff water from the watershed would be stored. 3)Reuse irrigation would be executed. 4)The water which equals the volume saved by reuse irrigation is conveyed and released during non-irrigation period.

  11. Effects of long term irrigation with polluted water and sludge amendment on some soil enzyme activities

    SciTech Connect

    Topac, F.O.; Baskaya, H.S.; Alkan, U.; Katkat, A.V.

    2008-01-15

    The objective of this study was to determine the effects of wastewater sludge-fly ash mixtures on urease, dehydrogenase, alkaline phosphatase and beta-glucosidase activities in soils. In order to evaluate the probable effects of previous soil management practices (irrigation with polluted water) on soil enzymes, two different soil samples which were similar in physical properties, but different in irrigation practice were used. The application of wastewater sludges supplemented with varying doses of fly ash increased potential enzyme activities for a short period of time (3 months) in comparison to unamended soils. However, the activity levels generally showed a decreasing trend with increasing ash ratios indicating the inhibitory effect of fly ash. The urease and dehydrogenase activities were particularly lower in soils irrigated from a polluted stream, indicating the negative effects of the previous soil management on soil microbial activity.

  12. A review of elevated atmospheric CO2 effects on plant growth and water relations: implications for horticulture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Empirical records provide incontestable evidence for the global rise in CO2 concentration in the earth's atmosphere. Plant growth can be stimulated by elevation of CO2; photosynthesis increases and economic yield is often enhanced. The application of more CO2 can increase plant water use efficiency ...

  13. Propagation of biases in humidity in the estimation of global irrigational water

    NASA Astrophysics Data System (ADS)

    Masaki, Y.; Hanasaki, N.; Takahashi, K.; Hijioka, Y.

    2015-01-01

    Future projections on irrigational water under a changing climate are highly dependent on meteorological data derived from general circulation models (GCMs). Since climate projections include biases, bias correction is widely used to adjust meteorological elements, such as the atmospheric temperature and precipitation, but less attention has been paid to biases in humidity. Hence, in many cases, raw GCM outputs have been directly used to analyze the impact of future climate change. In this study, we examined how the biases remaining in the humidity data of five GCMs propagate into the estimation of irrigational water demand and abstraction from rivers using the global hydrological model (GHM) H08. First, to determine the effects of humidity bias across GCMs, we used meteorological data sets to which a state-of-the-art bias correction method was applied except to the humidity. Uncorrected GCM outputs were used for the humidity. We found that differences in the monthly relative humidity of 11.7 to 20.4% RH (percent used as the unit of relative humidity) from observations across the GCMs caused the estimated irrigational water abstraction from rivers to range between 1217.7 and 1341.3 km3 yr-1 for 1971-2000. Differences in humidity also propagate into future projections. Second, sensitivity analysis with hypothetical humidity biases of ±5% RH added homogeneously worldwide revealed the large negative sensitivity of irrigational water abstraction in India and East China, which have high areal fractions of irrigated cropland. Third, we performed another set of simulations with bias-corrected humidity data to examine whether bias correction of the humidity can reduce uncertainties in irrigational water across the GCMs. The results showed that bias correction, even with a primitive methodology that only adjusts the monthly climatological relative humidity, helped reduce uncertainties across the GCMs. Although the GHMs have different sensitivities to atmospheric humidity

  14. Experimental evaluation of four infiltration models for calcareous soil irrigated with treated untreated grey water and fresh water

    NASA Astrophysics Data System (ADS)

    Gharaibeh, M. A.; Eltaif, N. I.; Alrababah, M. A.; Alhamad, M. N.

    2009-04-01

    Infiltration is vital for both irrigated and rainfed agriculture. The knowledge of infiltration characteristics of a soil is the basic information required for designing an efficient irrigation system. The objective of the present study was to model soil infiltration using four models: Green and Ampt, Horton, Kostaikov and modified Kostiakov. Infiltration tests were conducted on field plot irrigated with treated, untreated greywater and fresh water. The field water infiltration data used in these models were based on double ring infiltrometer tests conducted for 4 h. The algebraic parameters of the infiltration models and nonlinear least squares regression were fitted using measured infiltration time [I (t)] data. Among process-based infiltration models, the Horton model performed best and matched the measured I (t) data with lower sum of squares (SS).

  15. Modeling the Climate Change Adaptation of Crop Production using Irrigation over Water-Limited Region

    NASA Astrophysics Data System (ADS)

    Okada, M.; Iizumi, T.; Sakurai, G.; Sakai, T.; Yokozawa, M.

    2014-12-01

    Replacing rainfed cropping system by irrigated one is assumed to be an effective measure for climate change adaptation in agriculture. However, in many agricultural impact assessments, future irrigation scenarios are externally given and do not consider the space-time varying available agricultural water under changing climate and land use. For these reason, this study aimed to (1) develop a crop-river coupled model that can simultaneously simulate crop growth and yield over a river watershed, river discharge and their dynamic interactions by embedded a large-area crop model, PRYSBI-2 [Sakurai et al., 2014] into a hydrologic model, H08 [Hanasaki et al., 2008]; (2) apply the developed coupled model to the Songhua River watershed in Northeast China and evaluate the model's performance by comparing the historical model simulations outputs; (3) assess the effects of adaption measure expanding irrigated area under climate change. The modeled year-to-year variations in soil moisture were comparable to the reference with the Pearson's correlation coefficient (r) of 0.75 (p<0.001) and root-mean-square error (RMSE) of 13 %. The modeled river discharge accurately matched with the observation data with the r of 0.83 (p<0.01) and RMSE of 22 %. And the modeled soybean yields were quantitatively comparable to the reference with the r of 0.66 (p<0.001) and RMSE of 21 %. We made simulations to project the changes of potential soybean production under climate change scenarios and irrigation area expanding scenarios. It was projected that the soybean production effectively increase until the irrigated area has been increased 5 times compared to around the year 2000. However, the more increase in the irrigated area would bring significant reduction of the increase rate in soybean production due to depletion of available agricultural water resources.

  16. Natural Wetlands Mediate Non-point Source Water Pollution From Irrigated Pastures

    NASA Astrophysics Data System (ADS)

    Knox, K.; Dahlgren, R. A.; Tate, K. W.

    2005-12-01

    Non-point source discharge from grazed pastures may be high in nutrients, sediment, and pathogens, three major contributors to water quality impairment in California. Intercepting pollution at its source and managing water quality within the landscape are essential to maintaining healthy downstream waters. We investigated the efficacy of flow-through wetlands interspersed throughout the agricultural landscape to reduce non-point source pollution of tailwater from cattle-grazed, irrigated pastures in the Sierra Nevada Foothills of California. Wetlands are known to positively impact water quality through ecological processes such as filtration, sedimentation, microbial transformations and plant uptake of nutrients. Influent and effluent water of small (0.25 ha), natural wetlands located downstream from flood irrigated pastures was analyzed for Escherichia coli, NO3-N, total N, total suspended solids (TSS), total P, and dissolved organic carbon (DOC) throughout two summer irrigation seasons (June to October). We compared reductions of sediment, nutrients and E. coli provided by a healthy, non-degraded wetland with reductions from flow through a channelized, degraded wetland. Large reductions in E. coli (>75%) and TSS (>50%) were observed in water exiting the healthy wetland while nutrient and DOC (~ 20%) concentrations were less affected by flow through the wetland. The channelized wetland provided smaller reductions in all constituents than did the non-degraded wetland. Results from this study demonstrate that small flow-through wetlands can improve water quality through the attenuation of E. coli and suspended sediments, and to a lesser degree DOC and nutrients.

  17. Optimal dynamic water allocation: Irrigation extractions and environmental tradeoffs in the Murray River, Australia

    NASA Astrophysics Data System (ADS)

    Grafton, R. Quentin; Chu, Hoang Long; Stewardson, Michael; Kompas, Tom

    2011-12-01

    A key challenge in managing semiarid basins, such as in the Murray-Darling in Australia, is to balance the trade-offs between the net benefits of allocating water for irrigated agriculture, and other uses, versus the costs of reduced surface flows for the environment. Typically, water planners do not have the tools to optimally and dynamically allocate water among competing uses. We address this problem by developing a general stochastic, dynamic programming model with four state variables (the drought status, the current weather, weather correlation, and current storage) and two controls (environmental release and irrigation allocation) to optimally allocate water between extractions and in situ uses. The model is calibrated to Australia's Murray River that generates: (1) a robust qualitative result that "pulse" or artificial flood events are an optimal way to deliver environmental flows over and above conveyance of base flows; (2) from 2001 to 2009 a water reallocation that would have given less to irrigated agriculture and more to environmental flows would have generated between half a billion and over 3 billion U.S. dollars in overall economic benefits; and (3) water markets increase optimal environmental releases by reducing the losses associated with reduced water diversions.

  18. Water reuse for urban landscape irrigation: aspersion and health related regulations.

    PubMed

    Brissaud, F; Blin, E; Hemous, S; Garrelly, L

    2008-01-01

    The Mediterranean seaside resort of Le Grau du Roi includes 40 hectares of landscaped areas spray irrigated with river water supplied through a separate network. Wastewater collected from several municipalities is treated in an activated sludge wastewater treatment plant (WWTP) and polished in waste stabilization ponds (WSPs). Planned substitution of treated wastewater for river water is hindered by spray irrigation prohibition within a 100 m distance from houses and recreational areas. WWTP and WSP effluents were monitored for pathogens with a particular attention to Legionella in Spring and Summer 2006. Helminth eggs, salmonellae and enteroviruses were never detected neither in WWTP effluent nor in the ponds. Legionella spp content was slightly higher or of the order of magnitude of river water contents. Regarding Legionella pneumophila contents, WSP effluent did not significantly differ from the river water. E.coli and enterococci contents in WSP effluents complied with the "excellent quality" criteria of the European Directive for coastal bathing waters. Therefore, substituting WSP effluents to river water is unlikely to alter health risks related to spray irrigation and, in this case, the buffer zone required by the French water reuse guidelines appears being short of support. PMID:18401152

  19. [Model simulation of the transportation, transformation and accumulation of synthetic musks in soils input through recycle water irrigation].

    PubMed

    Wang, Mei-E; Chen, Wei-Ping; Jiao, Wen-Tao

    2012-12-01

    Environmental pollution of synthetic musks HHCB and AHTN, one type of PPCPs, have been attracted great attentions in latest years. One of the main input pathways of HHCB/AHTN to soils is reclaimed water irrigation. In this study, we monitored HHCB and AHTN in soils irrigated by reclaimed water and irrigation water and modeled the transportation and accumulation of HHCB and AHTN in soils using HYDRUS-1D. Results showed that concentrations of HHCB and AHTN in soils irrigated by recycling water were 5 times higher than tape water irrigation soils although both of the concentrations are trace. The temporal increase of accumulation was exponential when lgK(oc) value was 3.44, while linear when lgK(oc) were 4.12 and 4.86. Changes of half life of HHCB/AHTN did not affect their accumulation in surface soils. The downward transportation of HHCB and AHTN under recycling water irrigation was very slow. After 40 years of irrigation, it could only 53 cm at most favored conditionals. The downward movement was greatly impacted by the lgK(oc) values. The dissipation of those two synthetic musks through biological degradation and plant uptake were tiny. The highest dissipation rate through biological degradation and plant uptake was only 7.69% of the total input by reclaimed water irrigation after 40 years. The dissipation rate was increased with the decrease of lgK(oc) values and irrigation time. Results of this work may offer base for accurate assessing the ecological risks of HHCB and AHTN in soils caused by reclaimed water irrigation. PMID:23379132

  20. Irrigation-induced contamination of water, sediment, and biota in the western United States-synthesis of data from the National Irrigation Water Quality Program

    USGS Publications Warehouse

    Seiler, Ralph L.; Skorupa, Joseph P.; Naftz, David L.; Nolan, B. Thomas

    2003-01-01

    In October 1985 the U.S. Department of the Interior (DOI), through the National Irrigation Water Quality Program (NIWQP), began a series of field investigations at 26 areas in the Western United States to determine whether irrigation drainage has had harmful effects on fish, wildlife, and humans or has reduced beneficial uses of water. In 1992 NIWQP initiated the Data Synthesis Project to evaluate data collected during the field investigations. Geologic, climatologic, and hydrologic data were evaluated and water, sediment, and biota from the 26 areas were analyzed to identify commonalities and dominant factors that result in irrigation-induced contamination of water and biota. Data collected for the 26 area investigations have been compiled and merged into a common data base. The structure of the data base is designed to enable assessment of relations between contaminant concentrations in water, sediment, and biota. The data base is available to the scientific community through the World Wide Web at URL http://www.usbr.gov/niwqp. Analysis of the data base for the Data Synthesis included use of summary statistics, factor analysis, and logistic regression. A Geographic Information System was used to store and analyze spatially oriented digital data such as land use, geology and evaporation rates. In the U.S. Department of the Interior (DOI) study areas, samples of water, bottom sediment, and biota were collected for trace-element and pesticide analysis. Contaminants most commonly associated with irrigation drainage were identified by comparing concentrations in water with established criteria. For surface water, the criteria used were typically chronic criteria for the protection of freshwater aquatic life. Because ground water can discharge to the surface where wildlife can be exposed to it, the criteria used for ground water were both the maximum contaminant levels (MCL's) for drinking water and the chronic criteria for the protection of freshwater aquatic life

  1. Influences of coal mining water irrigation on the maize losses in the Xingdong Mine area, China.

    PubMed

    Sun, Yuzhuang; Ling, Pei; Li, Yanheng; Li, Qingxue; Sun, Quande; Wang, Jinxi

    2014-02-01

    In 2008, a maize underproduction disaster occurred in the Xianyu village after irrigation using the coal mining water from the Xingdong Mine, China. This disaster resulted in about 40 hectare maize underproduction and 20 hectare total loss of the maize yields. In order to study the reason, a total of 25 soil, water and plant samples were taken from the study area. These samples were analysed by inductively coupled plasma mass spectrometry and ion chromatography. The results indicate that the contents of both water-soluble fluorine and total fluorine are very high and resulting of maize underproduction and total loss of production. The possible pollution sources of fluorine in the study area could be from the coal mine water used for irrigation and glass chemical factory near the study area. PMID:23892594

  2. Effects on ground-water quality from irrigating pasture with sewage effluent near Lakeland, Florida

    USGS Publications Warehouse

    Reichenbaugh, R.C.

    1977-01-01

    Since 1969 an average of 25,000 gpd of domestic secondary-treated effluent has been used to supplement irrigation of 30 acres of grazed pasture north of Lakeland, Florida. Monitor wells were contructed near the effluent-irrigated pasture. The water table in the surficial aquifer under the pasture varied from 1.0 to 3.3 feet below land surface. Total nitrogen was less than 20 percent of the effluent content after percolating 8 feet; no increase in nitrogen was detected 20 feet below the surface, or in down-gradient ground water. There was no evidence of phosphorus or carbon contamination of ground water. Low numbers of bacteria (generally coliform) were noted in some samples from nine wells. Four wells sampled contained bacteria of probable fecal origin. Low-rate application of the effluent to the pasture apparently has had little effect on the soil and ground water. (Woodard-USGS)

  3. Mitigation of soil water repellency improves rootzone water status and yield in precision irrigated apples

    NASA Astrophysics Data System (ADS)

    Kostka, S.; Gadd, N.; Bell, D.

    2009-04-01

    Water repellent soils are documented to impact a range of hydrological properties, yet studies evaluating the consequences of soil water repellency (SWR) and its mitigation on crop yield and quality are conspicuously absent. With global concerns on drought and water availability and the projected impacts of climate change, development of novel strategies to optimize efficient rootzone delivery of water are required. Co-formulations of alkyl polyglycoside (APG) and ethylene oxide-propylene oxide (EO/PO) block copolymer surfactants have been shown to improve wetting synergistically. The objectives of this study were to determine if this surfactant technology: 1) increased soil water content and wetting front depth in mini-sprinkler irrigated, water repellent, Goulburn Valley clay loam soils and 2) assess the consequence of SWR mitigation on yield of Malus domestica Borkh. Three trials were conducted in the apple varieties 'Pink Lady' (2006/07 and 2007/08) and 'Gala' (2007/08) growing on Goulburn Valley clay loam soils in Victoria, AU. The test design was a randomized complete block with treatments replicated 5-6 times. Plot size varied by location. SWR was mitigated by applying surfactant at initial rates of 0, 5, or 10 L ha-1 in the spring, then at 0, 2.5, or 5 L ha-1 monthly for up to four months and compared to an untreated control. Treatments were applied to tree lines using a hand held small plot sprayer (118 liters of spray solution ha-1) followed by irrigation within 1-3 days of treatment applications. At each location, plots were irrigated by mini sprinklers and received the same irrigation volumes and management practices. Soil volumetric water content (VWC) was monitored at depths of 0-10 and 10-20 cm using a Theta probe (Delta-T Devices, Cambridge, UK). At harvest, fruit number and weights were measured and used for crop yield estimations. Data were analyzed using analysis of variance with mean values summarized and separated using Least Significant Test

  4. [Effects of different water-saving irrigation modes on chestnut growth and fruiting in drought hilly land].

    PubMed

    Tian, Shou-Le; Shen, Guang-Ning; Xu, Lin; Sun, Xiao-Li

    2012-03-01

    Taking the chestnut trees in a semi-arid and semi-humid hilly orchard of Tai' an, Shandong Province of East China as test objects, a field experiment was conducted to study the effects of different water-saving irrigation modes (pottery jar storing water, small hole storing water, and border irrigation with covering) on the soil moisture characteristics and the growth, fruiting, and development of chestnut roots. Comparing with the control (border irrigation), all the three water-saving irrigation modes could prolong the period of soil keeping moist, and the best effect came from pottery, jar treatment, with the soil keeping moist for 32 days, 13 days longer than the control. Under water-saving irrigations, the bearing branches length and number, leaf area and mass, and shoot mixed buds all increased obviously. Both pottery jar storing water and small hole storing water could irrigate deeper roots and induce root growth in deeper soil layers, and thus, relieve the drought stress on superficial roots. The three water-saving irrigation modes could increase chestnut yield markedly, with an increment of 18.8%, 16.5%, and 14.2%, respectively, as compared with the control. PMID:22720605

  5. Wheat Irrigation Management Using Multispectral Crop Coefficients: II. Irrigation Scheduling Performance, Grain Yield, and Water Use Efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current irrigation scheduling is based on well-established crop coefficient-reference evapotranspiration methods. However, appropriate irrigation scheduling can be negated when crop evapotranspiration (ETc) is poor due to imprecise crop coefficients. The premise of this research is that real-time mo...

  6. CONTROLLING WATER USE EFFICIENCY WITH IRRIGATION AUTOMATION: CASES FROM DRIP AND CENTER PIVOT IRRIGATION OF CORN AND SOYBEAN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A center pivot was completely automated using the temperature-time-threshold (TTT) method of irrigation scheduling. Methods are described that were used to automatically collect and analyze canopy temperature data and control the moving irrigation system based on the data analysis. Automatic irrigat...

  7. Effects of seedbed preparation, irrigation, and water harvesting on seedling emergence at the Nevada Test Site

    SciTech Connect

    Winkel, V.K.; Ostler, W.K.; Gabbert, W.D.; Lyon, G.E.

    1993-10-01

    Approximately 800 hectares on the US Department of Energy Nevada Test Site and vicinity are contaminated with plutonium. As part of a cleanup effort, both the indigenous vegetation and the top 5--10 cm of soil may be removed, and the soil may or may not be replaced. Technologies must be developed to stabilize and revegetate these lands. A study was developed to determine adaptable plant species, methods to prepare seedbeds for direct seeding and water harvesting, and proper irrigation rates. Plots were cleared of indigenous vegetation, and then prepared with various seedbed/water harvesting treatments including, pitting, land imprinting, and mulching. Other plots were treated with large water harvesting structures. Three irrigation treatments were superimposed over the seedbed/water harvesting treatments. Seedling emergence data was collected, and the treatment combinations compared. Supporting meteorological and soil data were collected with an automatic data-logger. Specific data included soil water data from all treatment combinations, precipitation, and air temperature. Irrigation did extend the period of available water approximately two to three weeks, but in a year of above average precipitation, this extension did not generally aid germination and emergence of seeded species, and only slightly increased densities of species from the native seedbank. With the exception of increased shrub seedling densities in desert strips, there were no strong seedbed preparation/water harvesting treatment effects. In years of above-average rainfall, mulching and water harvesting treatments, and irrigation may not be necessary to insure adequate germination and emergence of adapted perennial grasses, forbs, and shrubs in the Mojave/Great Basin Transition Desert.

  8. Uncertainty in future irrigation water demand and risk of crop failure for maize in Europe

    NASA Astrophysics Data System (ADS)

    Webber, Heidi; Gaiser, Thomas; Oomen, Roelof; Teixeira, Edmar; Zhao, Gang; Wallach, Daniel; Zimmermann, Andrea; Ewert, Frank

    2016-07-01

    While crop models are widely used to assess the change in crop productivity with climate change, their skill in assessing irrigation water demand or the risk of crop failure in large area impact assessments is relatively unknown. The objective of this study is to investigate which aspects of modeling crop water use (reference crop evapotranspiration (ET0), soil water extraction, soil evaporation, soil water balance and root growth) contributes most to the variability in estimates of maize crop water use and the risk of crop failure, and demonstrate the resulting uncertainty in a climate change impact study for Europe. The SIMPLACE crop modeling framework was used to couple the LINTUL5 crop model in factorial combinations of 2–3 different approaches for simulating the 5 aspects of crop water use, resulting in 51 modeling approaches. Using experiments in France and New Zeland, analysis of total sensitivity revealed that ET0 explained the most variability in both irrigated maize water use and rainfed grain yield levels, with soil evaporation also imporatant in the French experiment. In the European impact study, net irrigation requirement differed by 36% between the Penman and Hargreaves ET0 methods in the baseline period. Average EU grain yields were similar between models, but differences approached 1–2 tonnes in parts of France and Southern Europe. EU wide esimates of crop failure in the historical period ranged between 5.4 years for Priestley–Taylor to every 7.9 years for the Penman ET0 methods. While the uncertainty in absolute values between models was significant, estimates of relative changes were similar between models, confirming the utility of crop models in assessing climate change impacts. If ET0 estimates in crop models can be improved, through the use of appropriate methods, uncertainty in irrigation water demand as well as in yield estimates under drought can be reduced.

  9. Influence of Sub-Surface Irrigation on Soil Conditions and Water Irrigation Efficiency in a Cherry Orchard in a Hilly Semi-Arid Area of Northern China

    PubMed Central

    Peng, Gao; Bing, Wang; Guangcan, Zhang

    2013-01-01

    Sub-surface irrigation (SUI) is a new water-saving irrigation technology. To explore the influence of SUI on soil conditions in a cherry orchard and its water-saving efficiency, experiments were conducted from 2009 to 2010 using both SUI and flood irrigation (FLI) and different SUI quotas in hilly semi-arid area of northern China. The results demonstrated the following: 1) The bulk density of the soil under SUI was 6.8% lower than that of soil under FLI (P<0.01). The total soil porosity, capillary porosity and non-capillary porosity of soils using SUI were 11.7% (P<0.01), 8.7% (P<0.01) and 43.8% (P<0.01) higher than for soils using FLI. 2) The average soil temperatures at 0, 5, 10, 15 and 20 cm of soil depth using SUI were 1.7, 1.1, 0.7, 0.4 and 0.3°C higher than those for FLI, specifically, the differences between the surface soil layers were more significant. 3) Compared with FLI, the average water-saving efficiency of SUI was 55.6%, and SUI increased the irrigation productivity by 7.9-12.3 kg m-3 ha-1. 4) The soil moisture of different soil layers using SUI increased with increases in the irrigation quotas, and the soil moisture contents under SUI were significantly higher in the 0-20 cm layer and in the 21-50 cm layer than those under FLI (P<0.01). 5) The average yields of cherries under SUI with irrigation quotas of 80-320 m3 ha-1 were 8.7%-34.9% higher than those in soil with no irrigation (CK2). The average yields of cherries from soils using SUI were 4.5%-12.2% higher than using FLI. It is appropriate to irrigate 2-3 times with 230 m3 ha-1 per application using SUI in a year with normal rainfall. Our findings indicated that SUI could maintain the physical properties, greatly improve irrigation water use efficiency, and significantly increase fruit yields in hilly semi-arid areas of northern China. PMID:24039986

  10. Effects of Irrigating with Treated Oil and Gas Product Water on Crop Biomass and Soil Permeability

    SciTech Connect

    Terry Brown; Jeffrey Morris; Patrick Richards; Joel Mason

    2010-09-30

    Demonstrating effective treatment technologies and beneficial uses for oil and gas produced water is essential for producers who must meet environmental standards and deal with high costs associated with produced water management. Proven, effective produced-water treatment technologies coupled with comprehensive data regarding blending ratios for productive long-term irrigation will improve the state-of-knowledge surrounding produced-water management. Effective produced-water management scenarios such as cost-effective treatment and irrigation will discourage discharge practices that result in legal battles between stakeholder entities. The goal of this work is to determine the optimal blending ratio required for irrigating crops with CBNG and conventional oil and gas produced water treated by ion exchange (IX), reverse osmosis (RO), or electro-dialysis reversal (EDR) in order to maintain the long term physical integrity of soils and to achieve normal crop production. The soils treated with CBNG produced water were characterized with significantly lower SAR values compared to those impacted with conventional oil and gas produced water. The CBNG produced water treated with RO at the 100% treatment level was significantly different from the untreated produced water, while the 25%, 50% and 75% water treatment levels were not significantly different from the untreated water. Conventional oil and gas produced water treated with EDR and RO showed comparable SAR results for the water treatment technologies. There was no significant difference between the 100% treated produced water and the control (river water). The EDR water treatment resulted with differences at each level of treatment, which were similar to RO treated conventional oil and gas water. The 100% treated water had SAR values significantly lower than the 75% and 50% treatments, which were similar (not significantly different). The results of the greenhouse irrigation study found the differences in biomass

  11. Contests In Conservation and Horticulture

    ERIC Educational Resources Information Center

    Jones, Richard D.

    1977-01-01

    Growing interest in conservation and horticulture in New York State has caused the addition of these specialized areas to the annual statewide agricultural education contests. Contest categories in both areas are listed. (MF)

  12. Native Americans' Interest in Horticulture.

    ERIC Educational Resources Information Center

    Meyer, Mary Hockenberry

    1999-01-01

    Focus groups arranged by local Native American Master Gardeners on two Minnesota reservations determined community interest in extension-horticulture programs. Topics of interest included food preservation and historical Native-American uses of plants. (SK)

  13. Microbial Survey of Pennsylvania Surface Water Used for Irrigating Produce Crops.

    PubMed

    Draper, Audrey D; Doores, Stephanie; Gourama, Hassan; LaBorde, Luke F

    2016-06-01

    Recent produce-associated foodborne illness outbreaks have been attributed to contaminated irrigation water. This study examined microbial levels in Pennsylvania surface waters used for irrigation, relationships between microbial indicator organisms and water physicochemical characteristics, and the potential use of indicators for predicting the presence of human pathogens. A total of 153 samples taken from surface water sources used for irrigation in southeastern Pennsylvania were collected from 39 farms over a 2-year period. Samples were analyzed for six microbial indicator organisms (aerobic plate count, Enterobacteriaceae, coliform, fecal coliforms, Escherichia coli, and enterococci), two human pathogens (Salmonella and E. coli O157), and seven physical and environmental characteristics (pH, conductivity, turbidity, air and water temperature, and sampling day and 3-day-accumulated precipitation levels). Indicator populations were highly variable and not predicted by water and environmental characteristics. Only five samples were confirmed positive for Salmonella, and no E. coli O157 was detected in any samples. Predictive relationships between microbial indicators and the occurrence of pathogens could therefore not be determined. PMID:27296593

  14. Changes in leaf water relations, gas exchange, growth and flowering quality in potted geranium plants irrigated with different water regimes.

    PubMed

    Sánchez-Blanco, Ma Jesús; Alvarez, Sara; Navarro, Alejandra; Bañón, Sebastián

    2009-03-15

    Geranium plants are an important part of urban green areas but suffer from drought, especially when grown in containers with a limited volume of medium. In this experiment, we examined the response of potted geraniums to different irrigation levels. Geranium (Pelargoniumxhortorum L.) seedlings were grown in a growth chamber and exposed to three irrigation treatments, whereby the plants were irrigated to container capacity (control), 60% of the control (moderate deficit irrigation, MDI), or 40% of the control (severe deficit irrigation, SDI). Deficit irrigation was maintained for 2 months, and then all the plants were exposed to a recovery period of 112 month. Exposure to drought induced a decrease in shoot dry weight and leaf area and an increase in the root/shoot ratio. Height and plant width were significantly inhibited by the SDI, while flower color parameters were not affected by deficit treatment. The number of wilting and yellow leaves increased, coinciding with the increase in the number of inflorescences and open flowers. Deficit irrigation led to a leaf water potential of about -0.8MPa at midday, which could have caused an important decrease in stomatal conductance, affecting the photosynthetic rate (Pn). Chlorophyll fluorescence (Fvm) values of 0.80 in all treatments throughout the experiment demonstrate the lack of drought-induced damage to PSII photochemistry. Pressure-volume analysis revealed low osmotic adjustment values of 0.2MPa in the SDI treatment, accompanied by increases in the bulk tissue elastic modulus (epsilon, wall rigidity) and resulting in turgor loss at lower leaf water potential values (-1.38MPa compared with -1.0MPa for the control). Leaf water potential values throughout the experiment below those for Psitlp were not found at any sampling time. By the end of the recovery period, the leaf water potential, stomatal conductance and net photosynthesis had recovered. We infer from these results that moderate deficit irrigation in geranium

  15. iCOLT: Seasonal prediction of water irrigation need in Emilia-Romagna (Italy)

    NASA Astrophysics Data System (ADS)

    Pavan, Valentina; Villani, Giulia; Spisni, Andrea; Pratizzoli, William; Tomei, Fausto; Botarelli, Lucio; Marletto, Vittorio

    2015-04-01

    Mediterranean regions are frequently exposed to water scarcity and an early assessment of the potential water requirements from summer crops is very important for water management at regional and Reclamation Consortia level. Since 2007, ARPA-SIMC has developed the operational climate service iColt (irrigazione e Classificazione delle cOLture in atto tramite Telerilevamento - irrigation and classification of crops by remote sensing), in order to monitor and predict potential water needs for crop irrigation at different geographical scales. iColt has three components: a) a classification of crops through a set of satellite images acquired at different phenological stages; b) calibrated multi-model ensemble seasonal predictions of climate indices, using as input the EUROSIP products; c) a crop water balance prediction by the model CRITERIA. The climate indices are predicted as input for a weather generator to produce an ensemble of daily meteorological time-series. The meteorological series together with the regional distribution of crops, classified by remote sensing, are used by the water balance and crop development model CRITERIA to assess the crop potential water requirement at geographical level during the following summer. CRITERIA includes an empirical model for computing the shallow water table through spring (observed ) and summer (predicted) meteorological data. The water requirements predictions are verified at the end of summer by forcing the water balance model using the observed meteorological data. The results obtained from 2011 to 2014 are described and show that the operational service has a better skill than the seasonal ensemble prediction products used as input. In all the years, the sign of the irrigation water requirements anomaly has been correctly forecasted. Furthermore, the system has shown to be able to capture the spatial variability of the predicted field. These encouraging results are thought to be due partly to the correct

  16. Estimating the impacts of a reservoir for improved water use in irrigation in the Yarabamba region, Peru

    NASA Astrophysics Data System (ADS)

    Swiech, Theoclea; Ertsen, Maurits W.; Pererya, Carlos Machicao

    The pressure on irrigation is increasing worldwide, not only because of - perceived or real - high water consumption in the irrigated sector, but also because an increased world population puts stress on food production. Numerous irrigated areas around the world face similar issues of water scarcity, disparity in water distribution and deficient infrastructure. As a result, farmers are typically restricted in their production strategies. A general strategy in the irrigation sector is the introduction of so-called modern techniques in existing irrigation systems, with the aim to increase agricultural production. This paper discusses such a modernization effort in the sub-basin of Yarabamba, Arequipa, Peru, in which a reservoir is being constructed to improve water use and stimulate economic development. Based on fieldwork, including interviews and scenario modeling with WEAP, the relationships between water users, their irrigation systems and the water balances in the basin were studied. Scenario studies showed that the reservoir might alleviate the current water shortages in the sub-basin, but that restrictions in the current infrastructure and management of irrigation may be of more importance than the reservoir. Especially existing interests and actions of upstream and downstream areas appear to be important factors; these will not be automatically solved with the new reservoir.

  17. Saline water irrigation effects on soil salinity distribution and some physiological responses of field grown Chemlali olive.

    PubMed

    Ben Ahmed, Chedlia; Magdich, Salwa; Ben Rouina, Bechir; Boukhris, Makki; Ben Abdullah, Ferjani

    2012-12-30

    The shortage of water resources of good quality is becoming an issue in arid and semi arid regions. Per consequent, the use of water resources of marginal quality is becoming an important consideration, particularly in arid regions in Tunisia, where large quantities of saline water are used for irrigation. Nevertheless, the use of these waters in irrigated lands requires the control of soil salinity and a comprehensive analysis even beyond the area where water is applied. The aim of this study was to investigate the effects of saline water irrigation on soil salinity distribution and some physiological traits of field-grown adult olive trees (Olea europaea L. cv. Chemlali) under contrasting environmental conditions of the arid region in the south of Tunisia. The plants were subjected, over two growing seasons, to two drip irrigated treatments: fresh water (ECe=1.2 dS m(-1), FW) and saline water (ECe=7.5 dS m(-1), SW). Saline water irrigation (SW) has led to a significant increase in soil salinity. Furthermore, these results showed that soil salinity and soil moisture variations are not only dependent on water salinity level but are also controlled by a multitude of factors particularly the soil texture, the distance from the irrigation source and climatic conditions (rainfall pattern, temperature average, …). On the other hand, salt treatment reduced leaf midday water potential (LMWP), relative water content and photosynthetic activity and increased the leaf proline content, and this increase was season-dependent. Indeed, LMWP in SW plants decreased to -3.71 MPa. Furthermore, the highest level of proline in SW plants was registered during summer period (2.19 μmol/mg Fw). The proline accumulation recorded in stressed plants has allowed them to preserve appropriate leaf water status and photosynthetic activity. More to the point, this olive cultivar seems to be more sensible to soil salinity during the intense growth phase. Such tendencies would help to better

  18. Canopy gas exchange and water use efficiency of 'Empire' apple in response to particle film, irrigation, and microclimatic factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the interaction between a reflective particle film and water use efficiency (WUE) response of irrigated and non-irrigated apple trees over a wide range of environmental conditions. The objectives were to measure the specific gas exchange and WUE response of 'Empire' apple treate...

  19. Enteric pathogen survival varies substantially in irrigation water from Belgian lettuce producers.

    PubMed

    Van Der Linden, Inge; Cottyn, Bart; Uyttendaele, Mieke; Berkvens, Nick; Vlaemynck, Geertrui; Heyndrickx, Marc; Maes, Martine

    2014-01-01

    It is accepted that irrigation water is a potential carrier of enteric pathogens, such as Salmonella and E. coli O157:H7 and, therefore, a source for contamination of fresh produce. We tested this by comparing irrigation water samples taken from five different greenhouses in Belgium. The water samples were inoculated with four zoonotic strains, two Salmonella and two E. coli O157:H7 strains, and pathogen survival and growth in the water were monitored up till 14 days. The influence of water temperature and chemical water quality was evaluated, and the survival tests were also performed in water samples from which the resident aquatic microbiota had previously been eliminated by filter sterilization. The pathogen's survival differed greatly in the different irrigation waters. Three water samples contained nutrients to support important growth of the pathogens, and another enabled weaker growth. However, for all, growth was only observed in the samples that did not contain the resident aquatic microbiota. In the original waters with their specific water biota, pathogen levels declined. The same survival tendencies existed in water of 4 °C and 20 °C, although always more expressed at 20 °C. Low water temperatures resulted in longer pathogen survival. Remarkably, the survival capacity of two E. coli 0157:H7 strains differed, while Salmonella Thompson and Salmonella Typhimurium behaved similarly. The pathogens were also transferred to detached lettuce leaves, while suspended in two of the water samples or in a buffer. The effect of the water sample on the pathogen's fitness was also reproduced on the leaves when stored at 100% relative humidity. Inoculation of the suspension in buffer or in one of the water samples enabled epiphytic growth and survival, while the pathogen level in the other water sample decreased once loaded on the leaves. Our results show that irrigation waters from different origin may have a different capacity to transmit enteric pathogens and an

  20. Long-term climate sensitivity of an integrated water supply system: The role of irrigation.

    PubMed

    Guyennon, Nicolas; Romano, Emanuele; Portoghese, Ivan

    2016-09-15

    The assessment of the impact of long-term climate variability on water supply systems depends not only on possible variations of the resources availability, but also on the variation of the demand. In this framework, a robust estimation of direct (climate induced) and indirect (anthropogenically induced) effects of climate change is mandatory to design mitigation measures, especially in those regions of the planet where the groundwater equilibrium is strongly perturbed by exploitations for irrigation purposes. The main goal of this contribution is to propose a comprehensive model that integrates distributed crop water requirements with surface and groundwater mass balance, able to consider management rules of the water supply system. The proposed overall model, implemented, calibrated and validated for the case study of the Fortore water supply system (Apulia region, South Italy), permits to simulate the conjunctive use of the water from a surface artificial reservoir and from groundwater. The relative contributions of groundwater recharges and withdrawals to the aquifer stress have been evaluated under different climate perturbations, with emphasis on irrigation practices. Results point out that irrigated agriculture primarily affects groundwater discharge, indicating that ecosystem services connected to river base flow are particularly exposed to climate variation in irrigated areas. Moreover, findings show that the recharge both to surface and to groundwater is mainly affected by drier climate conditions, while hotter conditions have a major impact on the water demand. The non-linearity arising from combined drier and hotter conditions may exacerbate the aquifer stress by exposing it to massive sea-water intrusion. PMID:27161129

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

    USGS Publications Warehouse

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

    2009-01-01

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

  2. Simulated Impacts of Climate Change on Water Use and Yield of Irrigated Sugarcane in South Africa

    NASA Technical Reports Server (NTRS)

    Jones, M.R; Singels, A.; Ruane, A. C.

    2015-01-01

    Reliable predictions of climate change impacts on water use, irrigation requirements and yields of irrigated sugarcane in South Africa (a water-scarce country) are necessary to plan adaptation strategies. Although previous work has been done in this regard, methodologies and results vary considerably. The objectives were (1) to estimate likely impacts of climate change on sugarcane yields, water use and irrigation demand at three irrigated sugarcane production sites in South Africa (Malelane, Pongola and La Mercy) for current (1980-2010) and future (2070-2100) climate scenarios, using an approach based on the Agricultural Model Inter-comparison and Improvement Project (AgMIP) protocols; and (2) to assess the suitability of this methodology for investigating climate change impacts on sugarcane production. Future climate datasets were generated using the Delta downscaling method and three Global Circulation Models (GCMs) assuming atmospheric CO2 concentration [CO2] of 734 ppm(A2 emissions scenario). Yield and water use were simulated using the DSSAT-Canegro v4.5 model. Irrigated cane yields are expected to increase at all three sites (between 11 and 14%), primarily due to increased interception of radiation as a result of accelerated canopy development. Evapotranspiration and irrigation requirements increased by 11% due to increased canopy cover and evaporative demand. Sucrose yields are expected to decline because of increased consumption of photo-assimilate for structural growth and maintenance respiration. Crop responses in canopy development and yield formation differed markedly between the crop cycles investigated. Possible agronomic implications of these results include reduced weed control costs due to shortened periods of partial canopy, a need for improved efficiency of irrigation to counter increased demands, and adjustments to ripening and harvest practices to counter decreased cane quality and optimize productivity. Although the Delta climate data

  3. Constraints and potentials of future irrigation water availability on agricultural production under climate change

    PubMed Central

    Elliott, Joshua; Deryng, Delphine; Müller, Christoph; Frieler, Katja; Konzmann, Markus; Gerten, Dieter; Glotter, Michael; Flörke, Martina; Wada, Yoshihide; Best, Neil; Eisner, Stephanie; Fekete, Balázs M.; Folberth, Christian; Foster, Ian; Gosling, Simon N.; Haddeland, Ingjerd; Khabarov, Nikolay; Ludwig, Fulco; Masaki, Yoshimitsu; Olin, Stefan; Rosenzweig, Cynthia; Ruane, Alex C.; Satoh, Yusuke; Schmid, Erwin; Stacke, Tobias; Tang, Qiuhong; Wisser, Dominik

    2014-01-01

    We compare ensembles of water supply and demand projections from 10 global hydrological models and six global gridded crop models. These are produced as part of the Inter-Sectoral Impacts Model Intercomparison Project, with coordination from the Agricultural Model Intercomparison and Improvement Project, and driven by outputs of general circulation models run under representative concentration pathway 8.5 as part of the Fifth Coupled Model Intercomparison Project. Models project that direct climate impacts to maize, soybean, wheat, and rice involve losses of 400–1,400 Pcal (8–24% of present-day total) when CO2 fertilization effects are accounted for or 1,400–2,600 Pcal (24–43%) otherwise. Freshwater limitations in some irrigated regions (western United States; China; and West, South, and Central Asia) could necessitate the reversion of 20–60 Mha of cropland from irrigated to rainfed management by end-of-century, and a further loss of 600–2,900 Pcal of food production. In other regions (northern/eastern United States, parts of South America, much of Europe, and South East Asia) surplus water supply could in principle support a net increase in irrigation, although substantial investments in irrigation infrastructure would be required. PMID:24344283

  4. Long-term effect of irrigation with waste water on soil microbial community in semi-arid conditions

    NASA Astrophysics Data System (ADS)

    García-Orenes, Fuensanta; Morugan, Alicia; Mar Alguacil, Mª; Roldan, Antonio

    2013-04-01

    The water shortage is one of the most serious environmental problems in semi-arid areas around the world, which implicates the search for alternatives sources of water to satisfy the water demand in these regions. The use of wastewater for the irrigation of agricultural land is one of most suitable solutions to save better quality water when the natural resources are scarce. The reuse of wastewater in soil irrigation is not a new practise and is increasing in many places around the world; however the implications for the sustainability of agro-ecosystems must be studied in deep. The objective of this work was to study the effects of the long-term irrigation with treated wastewater in soil microbial community (evaluated as abundance of phospholipid fatty acids, PLFA). The experiment was conducted in an area located in Alicante (Southeast Spain) (Coordinates 38° 17´38" N, 0° 33´50" W). During 40 years an experimental Citrus aurantium L. (orange tree) orchard has been drip-irrigated with waste water, and control plots with the same characteristics subjected to drip irrigation with fresh water, were also stabilised during all the experimental period. Soil samples from individual trees were colleted in a randomised design with three replicates for each irrigation treatment (irrigation with waste water and irrigation with fresh water), to analyse the abundance of PLFA at the end of the experiment. The results show a major content of total PLFA in soils irrigated with fresh water, also these soils showed higher variety of PLFAs, and so a higher variety of groups of microorganims.

  5. [Modeling the Cd accumulation in agricultural soil irrigated with reclaimed water].

    PubMed

    Zhao, Zhong-Ming; Chen, Wei-Ping; Jiao, Wen-Tao; Wang, Mei-E

    2012-12-01

    Recent years, soil pollution of heavy metal has affected human life seriously, especially in farmland. Heavy metal pollution in farmland is mainly caused by irrigation, fertilizing and atmospheric fallout. As the character of heavy metal input in farmland is chronic and low dosage, application of model would be more suitable than routine methods to illustrate the dynamic changes of heavy metals in soil. In this paper, we use the model of STEM-profile to analyze and predict Cd pollution in farmland in Tongzhou, Beijing, based on the data from field survey. The results showed that: the concentration of Cd in this land would exceed the national soil environment standard after 100 years under current situations, reaching 0.866 mg x kg(-1) in plow layer. Studies of the influence of the amount and the form of inputs and the amount of irrigation water on the distribution of Cd in soil showed that irrigated with reclaimed water or fertilized with organic manure could lead to accumulation of Cd in the soil, while groundwater irrigation with inorganic fertilization would not cause accumulation of Cd in soil. When Cd inputs changed from mineral to organic form, the concentration of Cd in plow layer would be 0.943 mg x kg(-1) after 100 year. When the amount of irrigation water increased from 0.8 ET to 1.5 ET and to 2.0 ET, the plow layer Cd content would be 0.952, 0.784 and 0.638 mg x kg(-1) respectively. PMID:23379131

  6. Grey water treatment in a series anaerobic--aerobic system for irrigation.

    PubMed

    Abu Ghunmi, Lina; Zeeman, Grietje; Fayyad, Manar; van Lier, Jules B

    2010-01-01

    This study aims at treatment of grey water for irrigation, focusing on a treatment technology that is robust, simple to operate and with minimum energy consumption. The result is an optimized system consisting of an anaerobic unit operated in upflow mode, with a 1 day operational cycle, a constant effluent flow rate and varying liquid volume. Subsequent aerobic step is equipped with mechanical aeration and the system is insulated for sustaining winter conditions. The COD removal achieved by the anaerobic and aerobic units in summer and winter are 45%, 39% and 53%, 64%, re