WorldWideScience

Sample records for irrigation system china

  1. Assess the potential of solar irrigation systems for sustaining pasture lands in arid regions - A case study in Northwestern China

    International Nuclear Information System (INIS)

    Yu, Yingdong; Liu, Jiahong; Wang, Hao; Liu, Miao

    2011-01-01

    Highlights: → We figured out the appropriate indicators for solar irrigation. → We analyzed the economic benefits of solar irrigation system. → The geographic allocation of grasslands suitable for solar irrigation in Qinghai province is presented. → The appropriate region for solar irrigation is also discussed. → The problems and countermeasures of PV pumping irrigation are considered. - Abstract: The combined impact of global climate change and increasing human activities has led to the severe deterioration of grasslands in China. Using the solar irrigation systems is an effective way for sustaining pasture lands in arid regions. A solar irrigation system is the device that uses the solar cell from the sun's radiation to generate electricity for driving the pump. And photovoltaic pump consists of an array of photovoltaic cells and pumps water from a well or reservoir for irrigation. Although ecologists and organizations constantly work and find ways to conserve grasslands through irrigation systems that use solar energy, issues on water resources are not yet thoroughly discussed. This paper takes into account the main factors in the study of water resources, including precipitation and groundwater, to analyze the feasibility of using a photovoltaic (PV) pumping irrigation. The appropriate area for such a PV pumping irrigation in Qinghai Province is also presented. The results show that the grasslands appropriate for PV pumping cover about 8.145 million ha, accounting for 22.3% of the grasslands in the entire province. Finally, the problems and countermeasures of PV pumping irrigation, including the impact on regional water balance, groundwater level and highland permafrost, are also considered.

  2. Implementing the Prepaid Smart Meter System for Irrigated Groundwater Production in Northern China: Status and Problems

    Directory of Open Access Journals (Sweden)

    Xiaowei Wang

    2017-05-01

    Full Text Available To reduce the gap between groundwater demand and supply caused by agricultural groundwater over-exploitation, the Prepaid Smart Meter System (PSMS is being strongly implemented by the Chinese government in northern China. This study reports the analysis and results of PSMS field surveys in six typical provinces in northern China as well as domestic literature reviews. Based on the architecture and implementation policies of the system, the implementation differences between areas and the influencing factors were analyzed, particularly the acknowledgment of farmers, the installation proportion of tube wells, the social benefits. Great achievements have been gained in the implementation, and the management targets have been achieved, including accurately metering overall irrigation groundwater production, assisting in the total amount control and quota management, reducing groundwater exploitation, and improving water use efficiency. However, shortcomings remain in the implementation process, such as single initial investment channels, imperfect policy system construction, a lack of retrieving and analyzing data, and the unbalanced development between areas. Countermeasures and suggestions for these problems are discussed in this article.

  3. Water users associations and irrigation water productivity in northern China

    NARCIS (Netherlands)

    Zhang, L.; Heerink, N.; Dries, L.K.E.; Qu, F.

    2013-01-01

    Traditional irrigation water management systems in China are increasingly replaced by user-based, participatory management through water users associations (WUAs) with the purpose to promote, economically and ecologically beneficial, water savings and increase farm incomes. Existing research shows

  4. Implementing the Prepaid Smart Meter System for Irrigated Groundwater Production in Northern China: Status and Problems

    OpenAIRE

    Xiaowei Wang; Jingli Shao; Frank van Steenbergen; Qiulan Zhang

    2017-01-01

    To reduce the gap between groundwater demand and supply caused by agricultural groundwater over-exploitation, the Prepaid Smart Meter System (PSMS) is being strongly implemented by the Chinese government in northern China. This study reports the analysis and results of PSMS field surveys in six typical provinces in northern China as well as domestic literature reviews. Based on the architecture and implementation policies of the system, the implementation differences between areas and the inf...

  5. Techno-economic feasibility of the irrigation system for the grassland and farmland conservation in China: Photovoltaic vs. wind power water pumping

    International Nuclear Information System (INIS)

    Campana, Pietro Elia; Li, Hailong; Yan, Jinyue

    2015-01-01

    Highlights: • A novel design procedure for photovoltaic and wind power water pumping systems for irrigation is proposed. • The design procedure is proved conducting dynamic simulations of the water supply and water demand. • The technical and economic effectiveness of photovoltaic water pumping systems is proved simulating the crop yield response. - Abstract: Photovoltaic water pumping (PVWP) and wind power water pumping (WPWP) systems for irrigation represent innovative solutions for the restoration of degraded grassland and the conservation of farmland in remote areas of China. The present work systematically compares the technical and economic suitability of such systems, providing a general approach for the design and selection of the suitable technology for irrigation purposes. The model calculates the PVWP and WPWP systems sizes based on irrigation water requirement (IWR), solar irradiation and wind speed. Based on the lowest PVWP and WPWP systems components costs, WPWP systems can compete with PVWP systems only at high wind speed and low solar irradiation values. Nevertheless, taking into account the average specific costs both for PVWP and WPWP systems, it can be concluded that the most cost-effective solution for irrigation is site specific. According to the dynamic simulations, it has also been found that the PVWP systems present better performances in terms of matching between IWR and water supply compared to the WPWP systems. The mismatch between IWR and pumped water resulted in a reduction of crop yield. Therefore, the dynamic simulations of the crop yield are essential for economic assessment and technology selection

  6. Scale Effects of Water Saving on Irrigation Efficiency: Case Study of a Rice-Based Groundwater Irrigation System on the Sanjiang Plain, Northeast China

    Directory of Open Access Journals (Sweden)

    Haorui Chen

    2017-12-01

    Full Text Available This research analyzed the scale effect of water saving in Bielahonghe (BLH Basin, a rice-cultivating district on the Sanjiang Plain, Northeast China. Water budgets with different surface irrigation water supply ratios and water-saving measures were simulated with a semi-distributed water balance model. PFnws, representing the ratio of rice evapotranspiration to net water supply (the total amount of irrigation and precipitation minus the amount of water reused, was employed to assess the water use efficiency. Seven spatial scales (noted from S1 to S7, ranging from a single field (317.87 ha to the whole basin (about 100,800 ha were determined. PFnws values were quantified across scales and several water-saving measures, including water-saving irrigation regimes, canal lining, and a reduction of the surface water supply ratio (SWSR. The results indicated that PFnws increased with scale and could be calculated by a fitted power function (PFnws = 0.736Area0.033, R2 = 0.58. Furthermore, PFnws increased most prominently when the scale increased from S1 to S2. The water-saving irrigation regime (WSIR had the most substantial water-saving effect (WSE at S1. Specifically, PFnws improved by 21.2% at S1 when high-intensity WSIR was applied. Additionally, the WSE values of S3 and S5 were slightly higher than at other scales when the branch canal water delivery coefficient increased from 0.65 to 0.80 through canal lining. Furthermore, the PFnws at each scale varied with SWSR. Specifically, PFnws from S3 to S7 improved as SWSR decreased from 0.4 to 0.3 but remained approximately constant when SWSR decreased from 0.3 to 0.

  7. HYDRUS Simulation of Sustainable Brackish Water Irrigation in a Winter Wheat-Summer Maize Rotation System in the North China Plain

    Directory of Open Access Journals (Sweden)

    Kangkang He

    2017-07-01

    Full Text Available Freshwater resources in the North China Plain (NCP are near depletion due to the unceasing overexploitation of deep groundwater, by far the most significant source of freshwater in the region. To deal with the deepening freshwater crisis, brackish water (rich but largely unused water in agriculture is increasingly being used in irrigation in the region. However, inappropriate irrigation with brackish water could lead to soil salinization and cropland degradation. To evaluate such negative impacts, the HYDRUS-1D model was used to simulate soil salt transport and accumulation under 15 years of irrigation with brackish water. The irrigation scenarios included brackish water irrigation during the wintering and jointing stages of winter wheat and then freshwater irrigation just before the sowing of summer maize. Freshwater irrigation was done to leach out soil salts, which is particularly vital in dry years. For the littoral region of the plain, HYDRUS-ID was used to simulate the irrigated cropping system stated above for a total period of 15 years. The results showed that it was feasible to use brackish water twice in one year, provided freshwater irrigation was performed before sowing summer maize. Freshwater irrigation, in conjunction with precipitation, leached out soil salts from the 100 cm root-zone depth. The maximum salt accumulation was in the 160–220 cm soil layer, which ensured that root-zone soil was free of restrictive salinity for crop growth. Precipitation was a critical determinant of the rate and depth leaching of soil salt. Heavy rainfall (>100 mm caused significant leaching of soluble salts in the 0–200 cm soil profile. Salt concentration under brackish water irrigation had no significant effect on the variations in the trend of soil salt transport in the soil profile. The variations of soil salinity were mainly affected by hydrological year type, for which the buried depth of soil salt was higher in wet years than in dry years

  8. Impact of irrigation with high arsenic burdened groundwater on the soil–plant system: Results from a case study in the Inner Mongolia, China

    International Nuclear Information System (INIS)

    Neidhardt, H.; Norra, S.; Tang, X.; Guo, H.; Stüben, D.

    2012-01-01

    Consequences of irrigation by arsenic (As) enriched groundwater were assigned in the Hetao Plain, part of Chinas’ Inner Mongolia Autonomous Region. Examinations followed the As flow path from groundwater to soil and finally plants. A sunflower and a maize field were systematically sampled, each irrigated since three years with saline well water, characterized by elevated As concentrations (154 and 238 μg L −1 ). The annual As input per m 2 was estimated as 120 and 186 mg, respectively. Compared to the geogenic background, As concentrations increased toward the surface with observed enrichments in topsoil being relatively moderate (up to 21.1 mg kg −1 ). Arsenic concentrations in plant parts decreased from roots toward leaves, stems and seeds. It is shown that the bioavailability of As is influenced by a complex interplay of partly counteracting processes. To prevent As enrichment and soil salinization, local farmers were recommended to switch to a less problematic water source. - Highlights: ► We examined influences of irrigation with As burdened water at two fields. ► As distribution within soil–plant system in Hetao Plain, PR China. ► Three years of flood irrigation with As containing groundwater. ► Annual As inputs per m 2 were estimated as 120 mg and 186 mg, respectively. ► Contents in topsoil and plants are partly elevated, but not critical yet. - Recent irrigation with groundwater raises the risk of As entering the local food chain in one of the oldest crop producing areas in the People’s Republic of China.

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

    Directory of Open Access Journals (Sweden)

    Shufeng Chen

    2017-02-01

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

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

    NARCIS (Netherlands)

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

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    M. H. J. P. Gunarathna

    2018-03-01

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

  12. Online decision support system for surface irrigation management

    Science.gov (United States)

    Wang, Wenchao; Cui, Yuanlai

    2017-04-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  14. GSM BASED IRRIGATION CONTROL AND MONITORING SYSTEM

    OpenAIRE

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

    2013-01-01

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

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

    NARCIS (Netherlands)

    Delos Reyes, M.L.F.

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Dan Chen

    2013-01-01

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

  17. Condensation irrigation a system for desalination and irrigation

    International Nuclear Information System (INIS)

    Lindblom, J.; Nordell, B

    2006-01-01

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

  18. performance evaluation of sprinkler irrigation system at mambilla

    African Journals Online (AJOL)

    HOD

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

  19. Social capital influences farmer participation in collective irrigation management in Shaanxi Provence, China

    NARCIS (Netherlands)

    Miao, S.; Heijman, W.J.M.; Xueqin Zhu, Xueqin; Lu, Q.

    2015-01-01

    Purpose – The purpose of this paper is to investigate the influence of four components of social capital on farmers’ participative behaviour in collective actions for constructing and operating small-scale groundwater irrigation systems on the Guanzhong Plain, Shaanxi Province, China.

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

    Science.gov (United States)

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

    2010-09-01

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

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

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    BROWN; Larry

    2009-01-01

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

  3. An improved delivery system for bladder irrigation.

    Science.gov (United States)

    Moslemi, Mohammad K; Rajaei, Mojtaba

    2010-10-05

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

  4. Drip irrigation using a PLC based adaptive irrigation system

    OpenAIRE

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

    2009-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Li Jiang

    2014-03-01

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

  6. Decision support system for surface irrigation design

    OpenAIRE

    Gonçalves, José M.; Pereira, L.S.

    2009-01-01

    The SADREG decision support system was developed to help decision makers in the process of design and selection of farm surface irrigation systems to respond to requirements of modernization of surface irrigation—furrow, basin, and border irrigation. It includes a database, simulation models, user-friendly interfaces, and multicriteria analysis models. SADREG is comprised of two components: design and selection. The first component applies database information, and through several si...

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

    Science.gov (United States)

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

    2018-03-15

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

  8. Automated Irrigation System for Greenhouse Monitoring

    Science.gov (United States)

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

    2018-06-01

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

  9. Automated Irrigation System for Greenhouse Monitoring

    Science.gov (United States)

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

    2018-03-01

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

  10. Modernisation strategy for National Irrigation Systems in the Philippines

    NARCIS (Netherlands)

    Delos Reyes, Mona Liza Fortunado

    2017-01-01

    The performance of publicly funded canal irrigation systems or more commonly called national irrigation systems (NIS) in the Philippines remained below expectations despite considerable system rehabilitation and improvement efforts. The continued suboptimal performances were attributed to

  11. Modeled effects of irrigation on surface climate in the Heihe River Basin, Northwest China

    Science.gov (United States)

    Zhang, Xuezhen; Xiong, Zhe; Tang, Qiuhong

    2017-08-01

    In Northwest China, water originates from the mountain area and is largely used for irrigation agriculture in the middle reaches. This study investigates the local and remote impact of irrigation on regional climate in the Heihe River Basin, the second largest inland river basin in Northwest China. An irrigation scheme was developed and incorporated into the Weather Research and Forecasting (WRF) model with the Noah-MP land surface scheme (WRF/Noah-MP). The effects of irrigation is assessed by comparing the model simulations with and without consideration of irrigation (hereafter, IRRG and NATU simulations, respectively) for five growth seasons (May to September) from 2009 to 2013. As consequences of irrigation, daily mean temperature decreased by 1.7°C and humidity increased by 2.3 g kg-1 (corresponding to 38.5%) over irrigated area. The temperature and humidity of IRRG simulation matched well with the observations, whereas NATU simulation overestimated temperature and underestimated humidity over irrigated area. The effects on temperature and humidity are generally small outside the irrigated area. The cooling and wetting effects have opposing impacts on convective precipitation, resulting in a negligible change in localized precipitation over irrigated area. However, irrigation may induce water vapor convergence and enhance precipitation remotely in the southeastern portion of the Heihe River Basin.

  12. Effects of dripper discharge and irrigation frequency on growth and yield of maize in loess plateau of northwest china

    International Nuclear Information System (INIS)

    Xiukang, W.; Zhanbin, L.; Yingying, X.

    2014-01-01

    A field experiment was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, in northwestern China from 2010 to 2011 with four treatments and six replicates in a randomized complete block design to determine appropriate dripper discharge and irrigation frequency for maize (Zea mays, L.) irrigated by drip irrigated system. Dripper discharge was applied to maize 1L/h of dripper discharge, 2 days irrigation frequency and 100% of evaporation from a class a pan (T1), 2, 3 and 4 L/h corresponding to 4, 6 and 8 days irrigation frequency, and deficit irrigation water levels was 90%, 80% and 70% of evaporation (T2, T3 and T4), respectively. The results indicated that longest root, root activity, plant height, leaf area, biomass and grain yields values were highest in T1 in both years. The highest grain yield was obtained of 8.78 and 8.84 t ha-1 under T1 in both years, and the minimum yield was obtained with 8.15 and 7.78 t ha-1 under T4 in 2010 and 2011, respectively. The maximum irrigation water use efficiency (IWUE) was 3.247 and 3.283 kg m-3 in both years under T4. Despite the reduction of growth and grain yield in T3, the dripper discharge was 3L/h, 6 days irrigation frequency and 80% of evaporation was still high and acceptable for maize production and irrigation water use efficiency in Loess Plateau of Northwest China. (author)

  13. Never look a gift horse in the mouth or should you? Upgrading the Hare irrigation system in Southern Ethiopia

    NARCIS (Netherlands)

    Wegerich, K.; Dubale, T.; Bruins, B.

    2008-01-01

    The upgrading of the Hare Irrigation System was a joint undertaking of the governments of Ethiopia and the People's Republic of China. After completion of the primary and the secondary canals, farmers refused to take over responsibility of the system. Existing literature on the Hare Irrigation

  14. Research on monitoring system of water resources in irrigation region based on multi-agent

    International Nuclear Information System (INIS)

    Zhao, T H; Wang, D S

    2012-01-01

    Irrigation agriculture is the basis of agriculture and rural economic development in China. Realizing the water resource information of irrigated area will make full use of existing water resource and increase benefit of irrigation agriculture greatly. However, the water resource information system of many irrigated areas in our country is not still very sound at present, it lead to the wasting of a lot of water resources. This paper has analyzed the existing water resource monitoring system of irrigated areas, introduced the Multi-Agent theories, and set up a water resource monitoring system of irrigated area based on multi-Agent. This system is composed of monitoring multi-Agent federal, telemetry multi-Agent federal, and the Communication Network GSM between them. It can make full use of good intelligence and communication coordination in the multi-Agent federation interior, improve the dynamic monitoring and controlling timeliness of water resource of irrigated area greatly, provide information service for the sustainable development of irrigated area, and lay a foundation for realizing high information of water resource of irrigated area.

  15. Performance of arthroscopic irrigation systems assessed with automatic blood detection

    NARCIS (Netherlands)

    Tuijthof, G. J. M.; de Vaal, M. M.; Sierevelt, I. N.; Blankevoort, L.; van der List, M. P. J.

    2011-01-01

    During arthroscopies, bleeding episodes occur as a result of tissue damage. Irrigation systems assist in minimizing these disturbances. The performance of three arthroscopic irrigation systems in clearing bleeding episodes was evaluated objectively. One surgeon performed 99 shoulder arthroscopies

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

    African Journals Online (AJOL)

    2017-04-02

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

  17. Control system design for concrete irrigation channels

    OpenAIRE

    Strecker, Timm; Aamo, Ole Morten; Cantoni, Michael

    2017-01-01

    Concrete channels find use at the periphery of irrigation networks, for expansion and to replace small earthen channels given the relative ease of maintenance and elimination of seepage losses. In design, it is important to account for control system performance when dimensioning the channel infrastructure. In this paper, the design of a distributed controller is investigated in terms managing water-levels, and thereby the depth profile (i.e., amount of concrete) needed to support peak flow l...

  18. Soil and water management in spate irrigation systems in Eritrea

    NARCIS (Netherlands)

    Hadera, M.T.

    2001-01-01

    Spate irrigation has been practised over 100 years in the Red Sea coastal zone of Eritrea such as the Sheeb area. Main problem of the spate irrigation system is water shortage caused by irregular rainfall in the highlands of Eritrea and breaching of the irrigation structures by destructive

  19. Sediment Transport Model for a Surface Irrigation System

    Directory of Open Access Journals (Sweden)

    Damodhara R. Mailapalli

    2013-01-01

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

  20. Deficit irrigation and sustainable water-resource strategies in agriculture for China's food security.

    Science.gov (United States)

    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. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

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

    NARCIS (Netherlands)

    Kooij, van der S.

    2016-01-01

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

  2. Participatory Irrigation Management and Irrigation Water Use Efficiency in Maize Production: Evidence from Zhangye City, Northwestern China

    Directory of Open Access Journals (Sweden)

    Qing Zhou

    2017-10-01

    Full Text Available Water has become increasingly scarce in northwestern China due to climate change, economic growth and burgeoning population. Improving agriculture water use efficiency is of strategic significance in promoting socio-economic water productivity for arid and semi-arid inland river basins. Based on the household-level data collected in Zhangye City, which is located in the middle reaches of Heihe River Basin (HRB in northwestern China, irrigation water use efficiency (IWUE of maize is estimated based on stochastic frontier analysis. The impacts of influential factors, especially the participatory irrigation management (PIM through water user associations (WUAs, on IWUE were further examined. Results show that the estimated average Technical efficiency (TE and IWUE of maize production are 0.74 and 0.24, respectively. The participation level in irrigation management is very low, with only 40% of the respondents participating in WUA meetings. In addition, most have a relatively superficial understanding of the roles and management scheme of WUAs. Empirical results show that though significantly positive, the magnitude of the impact of PIM on IWUE is relatively small. Households that participated in WUA meetings achieved only 0.002% higher IWUEs than those have never participated in. WUAs are not operating with their designed objectives. Consequently, reform of the traditional management form of WUAs to make them more transparent, fair, and extensively participated in among farmers is in urgently need. In addition, we also find that water price, source of irrigation water, irrigation technology adoption and famers’ education level and farming experience also have significant positive impacts on IWUE.

  3. Economic optimization of photovoltaic water pumping systems for irrigation

    International Nuclear Information System (INIS)

    Campana, P.E.; Li, H.; Zhang, J.; Zhang, R.; Liu, J.; Yan, J.

    2015-01-01

    Highlights: • A novel optimization procedure for photovoltaic water pumping systems for irrigation is proposed. • An hourly simulation model is the basis of the optimization procedure. • The effectiveness of the new optimization approach has been tested to an existing photovoltaic water pumping system. - Abstract: Photovoltaic water pumping technology is considered as a sustainable and economical solution to provide water for irrigation, which can halt grassland degradation and promote farmland conservation in China. The appropriate design and operation significantly depend on the available solar irradiation, crop water demand, water resources and the corresponding benefit from the crop sale. In this work, a novel optimization procedure is proposed, which takes into consideration not only the availability of groundwater resources and the effect of water supply on crop yield, but also the investment cost of photovoltaic water pumping system and the revenue from crop sale. A simulation model, which combines the dynamics of photovoltaic water pumping system, groundwater level, water supply, crop water demand and crop yield, is employed during the optimization. To prove the effectiveness of the new optimization approach, it has been applied to an existing photovoltaic water pumping system. Results show that the optimal configuration can guarantee continuous operations and lead to a substantial reduction of photovoltaic array size and consequently of the investment capital cost and the payback period. Sensitivity studies have been conducted to investigate the impacts of the prices of photovoltaic modules and forage on the optimization. Results show that the water resource is a determinant factor

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

    Science.gov (United States)

    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.

  5. Effects of climatic factors, drought risk and irrigation requirement on maize yield in the Northeast Farming Region of China

    DEFF Research Database (Denmark)

    Yin, Xiaogang; Jabloun, Mohamed; Olesen, Jørgen Eivind

    2016-01-01

    Drought risk is considered to be among the main limiting factors for maize (Zea mays L.) production in the Northeast Farming Region of China (NFR). Maize yield data from 44 stations over the period 1961–2010 were combined with data from weather stations to evaluate the effects of climatic factors...... drought and intense rainfall illustrate the importance of further development of irrigation and drainage systems for ensuring the stability of maize production in NFR....

  6. Village-level supply reliability of surface water irrigation in rural China: effects of climate change

    Science.gov (United States)

    Li, Yanrong; Wang, Jinxia

    2018-06-01

    Surface water, as the largest part of water resources, plays an important role on China's agricultural production and food security. And surface water is vulnerable to climate change. This paper aims to examine the status of the supply reliability of surface water irrigation, and discusses how it is affected by climate change in rural China. The field data we used in this study was collected from a nine-province field survey during 2012 and 2013. Climate data are offered by China's National Meteorological Information Center which contains temperature and precipitation in the past 30 years. A Tobit model (or censored regression model) was used to estimate the influence of climate change on supply reliability of surface water irrigation. Descriptive results showed that, surface water supply reliability was 74 % in the past 3 years. Econometric results revealed that climate variables significantly influenced the supply reliability of surface water irrigation. Specifically, temperature is negatively related with the supply reliability of surface water irrigation; but precipitation positively influences the supply reliability of surface water irrigation. Besides, climate influence differs by seasons. In a word, this paper improves our understanding of the impact of climate change on agriculture irrigation and water supply reliability in the micro scale, and provides a scientific basis for relevant policy making.

  7. Radiation use efficiency and yield of winter wheat under deficit irrigation in North China

    International Nuclear Information System (INIS)

    Han, H.; Li, Z.; Ning, T.; Bai, M.; Zhang, X.; Shan, Y.

    2008-01-01

    An experiment was conducted in North China to investigate the effects of deficit irrigation and winter wheat varieties on the photosynthetic active radiation (PAR) capture ration, PAR utilization and grain yield. Field experiments involved Jimai 20 (J; high yield variety) and Lainong 0153 (L; dryland variety) with non-irrigation and irrigated at the jointing stage. The results showed that whether irrigated at jointing stage or not, there was no significant difference between J and L with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between the varieties with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface. This result was mainly caused by the changes in the vertical distributions of leaf area index. As a result, the effects of the varieties and deficit irrigation on the radiation use efficiency (RUE) and grain yield of winter wheat were due to the vertical distribution of PAR in the winter wheat canopies. During the late growing season of winter wheat, irrespective of the irrigation regime, the RUE and grain yield of J were significantly higher than those of L. These results suggest that a combination of deficit irrigation and a suitable winter wheat variety should be applied in North China

  8. Modeling irrigation behavior in groundwater systems

    Science.gov (United States)

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

    2014-08-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Xin Liu

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

  11. Quality of terrestrial data derived from UAV photogrammetry: a case study of the Hetao irrigation district in northern China

    Science.gov (United States)

    Zhang, Hongming; Baartman, Jantiene E. M.; Yang, Xiaomei; Gai, Lingtong; Geissen, Violette

    2017-04-01

    Most crops in northern China are irrigated, but the topography affects water use, soil erosion, runoff and yields,. Technologies for collecting high-resolution topographic data are essential for adequately assessing these effects. Ground surveys and techniques of light detection and ranging have good accuracy, but data acquisition can be time-consuming and expensive for large catchments. Recent rapid technological development has provided new, flexible, high-resolution methods for collecting topographic data, such as photogrammetry using unmanned aerial vehicles (UAVs). The accuracy of UAV photogrammetry for generating high-resolution digital elevation models (DEMs) and for determining the width of irrigation channels, however, has not been assessed. We used a fixed-wing UAV for collecting high-resolution (0.15 m) topographic data for the Hetao irrigation district, the third largest irrigation district in China. We surveyed 112 ground checkpoints (GCPs) using a real-time kinematic global positioning system to evaluate the accuracy of the DEMs and channel widths. A comparison of manually measured channel widths with the widths derived from the DEMs indicated that the DEM-derived widths had vertical and horizontal root mean square errors of 13.0 and 7.9 cm, respectively. UAV photogrammetric data can thus be used for land surveying, digital mapping, calculating channel capacity, monitoring crops, and predicting yields, with the advantages of economy, speed, and ease.

  12. Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area (SZIA), China*

    Science.gov (United States)

    Sun, Li-na; Yang, Xiao-bo; Wang, Wen-qing; Ma, Li; Chen, Su

    2008-01-01

    Heavy metal contamination of soils, derived from sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides, and so on, has been of wide concern in the last several decades. The Shenyang Zhangshi Irrigation Area (SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years. This study investigated the spatial distribution and temporal variation of soil cadmium (Cd) and copper (Cu) contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods. The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils. The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil (LSGSS) in China, and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990. The contamination magnitude of soil Cd and the soil extent of Cd contamination had evidently increased since sewage irrigation ceased in 1992. The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil, but obviously decresed in subsoil. The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation. The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils. PMID:18357631

  13. Alfalfa Water Use and Yield under Different Sprinkler Irrigation Regimes in North Arid Regions of China

    Directory of Open Access Journals (Sweden)

    Yan Li

    2017-08-01

    Full Text Available Alfalfa (Medicago sativa is one of the major crops grown in Northern China in recent years, however, the current serious water shortage conditions present a challenge to the growth of this crop, especially if efficient use of water is considered in forage production for sustainability. This study aimed to evaluate alfalfa productivity and water use efficiency (WUE under different sprinkler irrigation levels. This experiment was conducted at Shiyanghe Experimental Station for Water-Saving in Agriculture and Ecology of China Agricultural University in Wuwei, Gansu, China, over a period of two years. There were three irrigation treatments: A1: 100% measured evapotranspiration (ETc of alfalfa; A2: irrigation amount was 66% of A1; A3: irrigation amount was 33% of A1; and a control of A4: no irrigation during the growing season. A randomized block design with three replications were applied. The results showed that the ETc and forage yield of alfalfa decreased, while WUE and crude protein (CP increased with the decreasing irrigation amounts. The seasonal average ETc and yield ranged from 412 mm to 809 mm and from 11,577 to 18,636 kg/ha, respectively, under different irrigation levels. The highest yields were obtained from the first growth period in all treatments in both years, due to the winter irrigation and the longest growth period. Alfalfa grown under lesser irrigation treatment conditions had higher variability in ETc and yield, mainly due to the variability in the amount of rainfall during the growth period. The seasonal average WUE of treatments ranged from 22.78 to 26.84 kg/(mm·ha, and the highest WUE was obtained at the first growth period, regardless of treatments. Seasonal average CP content ranged from 18.99% to 22.99%. A significant linear relationship was found between yield and ETc or irrigation amount, and the fitting results varied between growth periods and years. The present results also implied that winter irrigation provided the

  14. Size and stochasticity in irrigated social-ecological systems

    Science.gov (United States)

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

    2017-03-01

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

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

    OpenAIRE

    Pant, D.R.

    2000-01-01

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

  16. LOW COST SMART SOLAR POWERED AUTOMATIC IRRIGATION SYSTEM

    OpenAIRE

    Hinsermu Alemayehu*, Kena Likassa

    2016-01-01

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

  17. Development of Solar Powered Irrigation System

    International Nuclear Information System (INIS)

    Abdelkerim, A I; Eusuf, M M R Sami; Salami, M J E; Aibinu, A; Eusuf, M A

    2013-01-01

    Development of a solar powered irrigation system has been discussed in this paper. This system would be SCADA-based and quite useful in areas where there is plenty of sunshine but insufficient water to carry out farming activities, such as rubber plantation, strawberry plantation, or any plantation, that requires frequent watering. The system is powered by solar system as a renewable energy which uses solar panel module to convert Sunlight into electricity. The development and implementation of an automated SCADA controlled system that uses PLC as a controller is significant to agricultural, oil and gas monitoring and control purpose purposes. In addition, the system is powered by an intelligent solar system in which solar panel targets the radiation from the Sun. Other than that, the solar system has reduced energy cost as well as pollution. The system is equipped with four input sensors; two soil moisture sensors, two level detection sensors. Soil moisture sensor measures the humidity of the soil, whereas the level detection sensors detect the level of water in the tank. The output sides consist of two solenoid valves, which are controlled respectively by two moistures sensors

  18. Simulation of hydrology and nitrate transport in the Hetao irrigation district, Inner Mongolia, China

    Science.gov (United States)

    Intensive agricultural activities in the Hetao irrigation district have severely degraded local aquatic ecosystems and water quality, and Ulansuhai Lake is now the most rapidly degrading eutrophic lake in China. A better understanding of the hydro-agronomic and pollutant transport processes in the a...

  19. Yield response and economics of shallow subsurface drip irrigation systems

    Science.gov (United States)

    Field tests were conducted using shallow subsurface drip irrigation (S3DI) on cotton (Gossypium hirsutum, L.), corn (Zea mays, L.), and peanut (Arachis hypogeae, L.) in rotation to investigate yield potential and economic sustainability of this irrigation system technique over a six year period. Dri...

  20. Performance evaluation of sprinkler irrigation system at Mambilla ...

    African Journals Online (AJOL)

    Variation in discharge can also be adjusted via use of uniform laterals, risers, and nozzles. This study further recommends an incorporation of a soil and water laboratory for the company to aid in monitoring the soil and water quality of the irrigation area. Keywords: Tea, irrigation System, Performance Evaluation ...

  1. Performance evaluation of a center pivot variable rate irrigation system

    Science.gov (United States)

    Variable Rate Irrigation (VRI) for center pivots offers potential to match specific application rates to non-uniform soil conditions along the length of the lateral. The benefit of such systems is influenced by the areal extent of these variations and the smallest scale to which the irrigation syste...

  2. Quixotic coupling between irrigation system and maize-cowpea ...

    African Journals Online (AJOL)

    A study was conducted at the Research and Experimental Station, Faculty of Agriculture, Ain Shams University at Shalakan, Kalubia Governorate, Egypt, to evaluate the effect of two irrigation systems (trickle and modified furrow irrigation) and five maize (M)-cowpea (C) intercropping patterns (sole M-30, sole M-15, ridge ...

  3. Energy savings potential from energy-conserving irrigation systems

    Energy Technology Data Exchange (ETDEWEB)

    Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

    1982-11-01

    This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

  4. Response of potato to drip and gun irrigation systems

    DEFF Research Database (Denmark)

    Zhenjiang, Zhou; Andersen, Mathias Neumann; Plauborg, Finn

    2015-01-01

    The objective of this study was to evaluate effects of different irrigation and N fertilization regimes by gun irrigation and drip-fertigation on potato production, and subsequently optimize the supply of water and N fertilizer to the growth condition of the specific season and minimize nitrate......-fertigation system (DFdsNds) and two gun irrigation systems (GIdsN120 and GIaN120) to display the differences on growth, yield and water use efficiency of potato. All treatments were irrigated according to model simulated soil water content. For fertilization all treatments received a basic dressing at planting of P......, K, Mg and micronutrients, and in addition 120 kg N/ha in the gun irrigated treatments and 36 kg N/ha in the drip-fertigated. For the latter, portion of 20 kg N/ha was applied whenever plant N concentration approached a critical value as simulated by the Daisy model. As a result differences in soil...

  5. System contemplations for precision irrigation in agriculture

    Science.gov (United States)

    Schubert, Martin J. W.

    2017-04-01

    This communication contemplates political, biological and technical aspects for efficient and profitable irrigation in sustainable agriculture. A standard for irrigation components is proposed. The need for many, and three-dimensionally distributed, soil measurement points is explained, thus enabling the control of humidity in selected layers of earth. Combined wireless and wired data transmission is proposed. Energy harvesting and storage together with mechanical sensor construction are discussed.

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

    Directory of Open Access Journals (Sweden)

    Ephraim Sekyi-Annan

    2018-05-01

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

  7. Economic optimization of photovoltaic water pumping systems for irrigation

    OpenAIRE

    Campana, Pietro Elia; Li, Hailong; Zhang, J.; Liu, J.; Yan, Jinyue

    2015-01-01

    Photovoltaic water pumping technology is considered as a sustainable and economical solution to provide water for irrigation, which can halt grassland degradation and promote farmland conservation in China. The appropriate design and operation significantly depend on the available solar irradiation, crop water demand, water resources and the corresponding benefit from the crop sale. In this work, a novel optimization procedure is proposed, which takes into consideration not only the availabil...

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

    Science.gov (United States)

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

    2015-04-01

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

  9. Adaptive Effectiveness of Irrigated Area Expansion in Mitigating the Impacts of Climate Change on Crop Yields in Northern China

    Directory of Open Access Journals (Sweden)

    Tianyi Zhang

    2017-05-01

    Full Text Available To improve adaptive capacity and further strengthen the role of irrigation in mitigating climate change impacts, the Chinese government has planned to expand irrigated areas by 4.4% by the 2030s. Examining the adaptive potential of irrigated area expansion under climate change is therefore critical. Here, we assess the effects of irrigated area expansion on crop yields based on county-level data during 1980–2011 in northern China and estimate climate impacts under irrigated area scenarios in the 2030s. Based on regression analysis, there is a statistically significant effect of irrigated area expansion on reducing negative climate impacts. More irrigated areas indicate less heat and drought impacts. Irrigated area expansion will alleviate yield reduction by 0.7–0.8% in the future but associated yield benefits will still not compensate for greater adverse climate impacts. Yields are estimated to decrease by 4.0–6.5% under future climate conditions when an additional 4.4% of irrigated area is established, and no fundamental yield increase with an even further 10% or 15% expansion of irrigated area is predicted. This finding suggests that expected adverse climate change risks in the 2030s cannot be mitigated by expanding irrigated areas. A combination of this and other adaptation programs is needed to guarantee grain production under more serious drought stresses in the future.

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

    African Journals Online (AJOL)

    The results revealed that the water use efficiency (WUE) and irrigation water use efficiency (IWUE) were typically higher in the AIS than in the conventional irrigation control system (CIS). Under the AIS treatment, the WUE and IWUE values were 1.64 and 1.37 k·gm-3 for wheat, and 7.50 and 6.50 kg·m-3 for tomato crops; ...

  11. Analytical Solution for Optimum Design of Furrow Irrigation Systems

    Science.gov (United States)

    Kiwan, M. E.

    1996-05-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

  13. Cooling effect of agricultural irrigation over Xinjiang, Northwest China from 1959 to 2006

    International Nuclear Information System (INIS)

    Han Songjun; Yang Zhiyong

    2013-01-01

    The influences of agricultural irrigation on trends in surface air temperature from 1959 to 2006 over Xinjiang, Northwest China are evaluated using data from 90 meteorological stations. The 90 stations are located in landscapes with markedly different cultivated land uses. The increasing trends in daily average temperature (T a ), maximum temperature (T max ), and minimum temperature (T min ) for May–September (the main growing season) are negatively correlated with cultivated land proportions within 4 km of the meteorological stations, as indicated by year 2000 land use data. The correlations between the trends in T max and cultivated land proportions are the most significant. The trends in T a , T max , and T min for May–September are expected to decrease by −0.018, −0.014, and −0.016 ° C per decade, respectively, along with a 10% increase in cultivated land proportion. As irrigated cultivated land occupies over 90% of total cultivated land, the dependence of temperature trends on cultivated area is attributed to irrigation. The cooling effects on stations with cultivated land proportion larger than 50% are compared to temperature trends in a reference group with cultivated land proportion smaller than 10%. The irrigation expansion from 1959 to 2006 over Xinjiang is found to be associated with cooling of May–September T a , T max , and T min by around −0.15 ° C to −0.10 ° C/decade in the station group with extensive irrigation. Short periods of rapid irrigation expansion co-occurred with the significant cooling of the May–September temperature. (letter)

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

    NARCIS (Netherlands)

    Urrutia Cobo, N.

    2006-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Lihua Lv

    2013-09-01

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

  16. Irrigation System through Intelligent Agents Implemented with Arduino Technology

    Directory of Open Access Journals (Sweden)

    Rodolfo SALAZAR

    2013-11-01

    Full Text Available The water has become in recent years a valuable and increasingly scarce. Its proper use in agriculture has demanded incorporate new technologies, mainly in the area of ICT. In this paper we present a smart irrigation system based on multi-agent architecture using fuzzy logic. The architecture incorporates different types of intelligent agents that an autonomous way monitor and are responsible for deciding if required enable / disable the irrigation system. This project proposes a real and innovative solution to the problem of inadequate water use with current irrigation systems employed in agricultural projects. This article presents the different technologies used, their adaptation to the solution of the problem and briefly discusses the first results obtained.

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

    Directory of Open Access Journals (Sweden)

    Ridwan Infandra I.Z.

    2018-01-01

    Full Text Available In agricultural field, irrigation is one of the most interesting considerations affecting the rate of plant growth and development. Micro-irrigation as the dripping or sprinkle method is one of the irrigation types that applies the small amount of water for fulfilling the humidity requirement. The most important factors affecting the demand of water for plants are soil conditions and effect of climatic factors. With less human labour required, to improve the irrigation method from the recent days, analyzing water used or water permeation automatically through the soil moisture has been raised as the interesting topic. Proposed in this research is the ring irrigation system (RIS which is introduced as an alternative channel for emitters that drip water directly onto the soil at the plant’s root zone where the soil conditions before and after watering can be quickly detected by the sensors. This RIS can be used for the potted plant, green house, or other small farm fields. Product design and development (PDD is applied in this research for assisting the designer to understand and create the RIS prototype properly according to the customer’s requirements where the suggested functions obtained will be added and tested.

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

    Directory of Open Access Journals (Sweden)

    Jaime Hoogesteger

    2015-03-01

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

  19. Influence of big power motors for irrigation of electric systems

    International Nuclear Information System (INIS)

    Shimoda, M.; Gialuca, V.; Trombetta, O.R.

    1988-01-01

    The evolution of rural electrification in CPFL - Companhia Paulista de Forca e Luz, Sao Paulo State, Brazil, and the influence of big power motors installation for irrigation in electric system are shown. Considerations about rural market, energy consumption, planning of distribution and transmission line and some calculations are also presented. (author)

  20. Control of soil moisture with radio frequency in a photovoltaic-powered drip irrigation system

    OpenAIRE

    DURSUN, Mahir; ÖZDEN, Semih

    2015-01-01

    Solar-powered irrigation systems are becoming increasingly widespread. However, the initial setup costs of these systems are very high. To reduce these costs, both the energy usage and the prevention of losses from irrigation systems are very important. In this study, a drip irrigation control system of 1000 dwarf cherry trees was controlled using soil moisture sensors in order to prevent excessive water consumption and energy losses in a solar-powered irrigation system. The control sys...

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

    Science.gov (United States)

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

  2. Phosphorus distribution in sandy soil profile under drip irrigation system

    International Nuclear Information System (INIS)

    El-Gendy, R.W.; Rizk, M.A.; Abd El Moniem, M.; Abdel-Aziz, H.A.; Fahmi, A.E.

    2009-01-01

    This work aims at to studying the impact of irrigation water applied using drip irrigation system in sandy soil with snap bean on phosphorus distribution. This experiment was carried out in soils and water research department farm, nuclear research center, atomic energy authority, cairo, Egypt. Snap bean was cultivated in sandy soil and irrigated with 50,37.5 and 25 cm water in three water treatments represented 100, 75 and 50% ETc. Phosphorus distribution and direction of soil water movement had been detected in three sites on the dripper line (S1,S2 and S3 at 0,12.5 and 25 cm distance from dripper). Phosphorus fertilizer (super phosphate, 15.5% P 2 O 5 in rate 300 kg/fed)was added before cultivation. Neutron probe was used to detect the water distribution and movement at the three site along soil profile. Soil samples were collected before p-addition, at end developing, mid, and late growth stages to determine residual available phosphorus. The obtained data showed that using 50 cm water for irrigation caused an increase in P-concentration till 75 cm depth in the three sites of 100% etc treatment, and covered P-requirements of snap bean for all growth stages. As for 37.5 and 25 cm irrigation water cannot cover all growth stages for P-requirements of snap bean. It could be concluded that applied irrigation water could drive the residual P-levels till 75 cm depth in the three sites. Yield of the crop had been taken as an indicator as an indicator profile. Yield showed good response according to water quantities and P-transportation within the soil profile

  3. Optimal Design and Operation of Permanent Irrigation Systems

    Science.gov (United States)

    Oron, Gideon; Walker, Wynn R.

    1981-01-01

    Solid-set pressurized irrigation system design and operation are studied with optimization techniques to determine the minimum cost distribution system. The principle of the analysis is to divide the irrigation system into subunits in such a manner that the trade-offs among energy, piping, and equipment costs are selected at the minimum cost point. The optimization procedure involves a nonlinear, mixed integer approach capable of achieving a variety of optimal solutions leading to significant conclusions with regard to the design and operation of the system. Factors investigated include field geometry, the effect of the pressure head, consumptive use rates, a smaller flow rate in the pipe system, and outlet (sprinkler or emitter) discharge.

  4. A rule-based smart automated fertilization and irrigation systems

    Science.gov (United States)

    Yousif, Musab El-Rashid; Ghafar, Khairuddin; Zahari, Rahimi; Lim, Tiong Hoo

    2018-04-01

    Smart automation in industries has become very important as it can improve the reliability and efficiency of the systems. The use of smart technologies in agriculture have increased over the year to ensure and control the production of crop and address food security. However, it is important to use proper irrigation systems avoid water wastage and overfeeding of the plant. In this paper, a Smart Rule-based Automated Fertilization and Irrigation System is proposed and evaluated. We propose a rule based decision making algorithm to monitor and control the food supply to the plant and the soil quality. A build-in alert system is also used to update the farmer using a text message. The system is developed and evaluated using a real hardware.

  5. An integrated crop and hydrologic modeling system to estimate hydrologic impacts of crop irrigation demands

    Science.gov (United States)

    R.T. McNider; C. Handyside; K. Doty; W.L. Ellenburg; J.F. Cruise; J.R. Christy; D. Moss; V. Sharda; G. Hoogenboom; Peter Caldwell

    2015-01-01

    The present paper discusses a coupled gridded crop modeling and hydrologic modeling system that can examine the benefits of irrigation and costs of irrigation and the coincident impact of the irrigation water withdrawals on surface water hydrology. The system is applied to the Southeastern U.S. The system tools to be discussed include a gridded version (GriDSSAT) of...

  6. Risk assessment and source analysis of soil heavy metal pollution from lower reaches of Yellow River irrigation in China.

    Science.gov (United States)

    Zhang, Pengyan; Qin, Chengzhe; Hong, Xin; Kang, Guohua; Qin, Mingzhou; Yang, Dan; Pang, Bo; Li, Yanyan; He, Jianjian; Dick, Richard P

    2018-08-15

    The level of concentration of heavy metal in soil is detrimental to soil quality. The Heigangkou-Liuyuankou irrigation area in the lower-reach of Yellow River irrigation, as home to a large population and a major site to agricultural production, is vulnerable to heavy metal pollution. This study examined soil quality in Heigangkou-Liuyuankou irrigation areas of Kaifeng, China. Pollution in soil and potential risks introduced by heavy metal accumulation were assessed using Nemerow, Geoaccumulation, and Hakanson's ecological risk indices. Statistics and Geographic Information Systems (GIS) were used to model and present the spatiotemporal changes of the pollution sources and factors affecting the levels of pollution. The heavy metals found in the sampled soil are Cr, Ni, Cu, Zn, Cd, Pb, As, and Hg. Among them, Cd is more concentrated than the others. The southwestern region of the studied area confronts the most serious heavy metal pollution. There exist spatial disparities of low concentrations of different heavy metals in the study area. Hg and Cd are found to pose the highest potential ecological risks. However, their risk levels are not the same across the study area. Levels concentration of Ni, Cu, Zn, Cd, Pb, As, and Hg in soil are highly correlated. In combination, they post an additional threat to the ecological environment. Transportation, rural settlements, and water bodies are found to be the major sources of Cr, Ni, Cu, Zn, Cd, Pb, and Hg pollution in the soil; among the major sources, transportation is the most significant factor. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Distribution and accumulation of endocrine-disrupting chemicals and pharmaceuticals in wastewater irrigated soils in Hebei, China

    International Nuclear Information System (INIS)

    Chen Feng; Ying Guangguo; Kong Lingxiao; Wang Li; Zhao Jianliang; Zhou Lijun; Zhang Lijuan

    2011-01-01

    This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate groundwater irrigated plot for comparison purpose. The results showed that the concentrations of the target compounds in the wastewater irrigated soils were in most cases higher than those in the groundwater irrigated soils. Among the 43 target compounds, nine compounds bisphenol-A, triclocarban, triclosan, 4-nonylphenol, salicylic acid, oxytetracycline, tetracycline, trimethoprim and primidone were detected at least once in the soils. Preliminary environmental risk assessment showed that triclocarban might pose high risks to terrestrial organisms while the other detected compounds posed minimal risks. Irrigation with wastewater could lead to presence or accumulation of some emerging contaminants to some extent in irrigated soils. - Highlights: → Some EDCs and PPCPs were detected in the wastewater irrigated soils. → Application of reclaimed water could lead to accumulation of some compounds. → Groundwater has been contaminated by some compounds. → Triclocarban posed high risks to soil organisms. - Application of reclaimed wastewater on agricultural land could lead to the presence or accumulation of wastewater-related contaminants in soils.

  8. Distribution and accumulation of endocrine-disrupting chemicals and pharmaceuticals in wastewater irrigated soils in Hebei, China

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Chen [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Ying Guangguo, E-mail: guangguo.ying@gmail.com [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Lingxiao, Kong [Institute of Plant Protection, Hebei Academy of Agriculture and Forestry Science, Baoding 07100 (China); Li, Wang; Jianliang, Zhao; Lijun, Zhou; Lijuan, Zhang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2011-06-15

    This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate groundwater irrigated plot for comparison purpose. The results showed that the concentrations of the target compounds in the wastewater irrigated soils were in most cases higher than those in the groundwater irrigated soils. Among the 43 target compounds, nine compounds bisphenol-A, triclocarban, triclosan, 4-nonylphenol, salicylic acid, oxytetracycline, tetracycline, trimethoprim and primidone were detected at least once in the soils. Preliminary environmental risk assessment showed that triclocarban might pose high risks to terrestrial organisms while the other detected compounds posed minimal risks. Irrigation with wastewater could lead to presence or accumulation of some emerging contaminants to some extent in irrigated soils. - Highlights: > Some EDCs and PPCPs were detected in the wastewater irrigated soils. > Application of reclaimed water could lead to accumulation of some compounds. > Groundwater has been contaminated by some compounds. > Triclocarban posed high risks to soil organisms. - Application of reclaimed wastewater on agricultural land could lead to the presence or accumulation of wastewater-related contaminants in soils.

  9. Regulations of irrigation on regional climate in the Heihe watershed, China, and its implications to water budget

    Science.gov (United States)

    Zhang, X.

    2015-12-01

    In the arid area, such as the Heihe watershed in Northwest China, agriculture is heavily dependent on the irrigation. Irrigation suggests human-induced hydro process, which modifies the local climate and water budget. In this study, we simulated the irrigation-induced changes in surface energy/moisture budgets and modifications on regional climate, using the WRF-NoahMP modle with an irrigation scheme. The irrigation scheme was implemented following the roles that soil moisture is assigned a saturated value once the mean soil moisture of all root layers is lower than 70% of fileld capacity. Across the growth season refering from May to September, the simulated mean irrigation amount of the 1181 cropland gridcells is ~900 mm, wihch is close to the field measurments of around 1000 mm. Such an irrigation largely modified the surface energy budget. Due to irrigation, the surface net solar radiation increased by ~76.7 MJ (~11 Wm-2) accouting for ~2.3%, surface latent and senbile heat flux increased by 97.7 Wm-2 and decreased by ~79.7 Wm-2 respectively; and local daily mean surface air temperature was thereby cooling by ~1.1°C. Corresponding to the surface energy changes, wind and circulation were also modified and regional water budget is therefore regulated. The total rainfall in the irrigation area increased due to more moisture from surface. However, the increased rainfall is only ~6.5mm (accounting for ~5% of background rainfall) which is much less than the increased evaporation of ~521.5mm from surface. The ~515mm of water accounting for 57% of total irrigation was transported outward by wind. The other ~385 mm accounting for 43% of total irrigation was transformed to be runoff and soil water. These results suggest that in the Heihe watershed irrigation largely modify local energy budget and cooling surface. This study also implicate that the existing irrigation may waste a large number of water. It is thereby valuable to develope effective irrigation scheme to

  10. Impact of reclaimed water irrigation on antibiotic resistance in public parks, Beijing, China

    International Nuclear Information System (INIS)

    Wang, Feng-Hua; Qiao, Min; Lv, Zhen-E; Guo, Guang-Xia; Jia, Yan; Su, Yu-Hong; Zhu, Yong-Guan

    2014-01-01

    The abundance and distribution of antibiotics and antibiotic resistance genes (ARGs) in soils from six parks using reclaimed water in Beijing, China, were characterized. Three classes of commonly used antibiotics (tetracycles, quinolones, and sulfonamides) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The highest concentrations of tetracyclines and quinolones were 145.2 μg kg −1 and 79.2 μg kg −1 , respectively. Detected tetG, tetW, sulI, and sulII genes were quantified by quantitative PCR. ARGs exhibited various abundances for different park soils. The integrase gene (intI1) as an indicator of horizontal gene transfer potential was also detected in high abundance, and had significant positive correlation with tetG, sulI, and sulII genes, suggesting that intI1 may be involved in ARGs dissemination. Both sulII and intI1 clones had high homology with some classes of pathogenic bacteria, such as Klebsiella oxytoca, Acinetobacter baumannii, Shigella flexneri, which could trigger potential public health concern. Highlights: • Reclaimed water irrigation could increase the concentration of antibiotics and ARGs in urban park soils. • ARGs can be persistent in the irrigated park soils, even without antibiotic selection pressure. • Both sulII and intI1 clones had high homology with some classes of pathogenic bacteria. -- The release of residual antibiotics and ARGs from reclaimed water could result in the proliferation of ARGs in irrigated park soils

  11. Economic compensation standard for irrigation processes to safeguard environmental flows in the Yellow River Estuary, China

    Science.gov (United States)

    Pang, Aiping; Sun, Tao; Yang, Zhifeng

    2013-03-01

    SummaryAgriculture and ecosystems are increasingly competing for water. We propose an approach to assess the economic compensation standard required to release water from agricultural use to ecosystems while taking into account seasonal variability in river flow. First, we defined agricultural water shortage as the difference in water volume between agricultural demands and actual supply after maintaining environmental flows for ecosystems. Second, we developed a production loss model to establish the relationship between production losses and agricultural water shortages in view of seasonal variation in river discharge. Finally, we estimated the appropriate economic compensation for different irrigation stakeholders based on crop prices and production losses. A case study in the Yellow River Estuary, China, demonstrated that relatively stable economic compensation for irrigation processes can be defined based on the developed model, taking into account seasonal variations in river discharge and different levels of environmental flow. Annual economic compensation is not directly related to annual water shortage because of the temporal variability in river flow rate and environmental flow. Crops that have stable planting areas to guarantee food security should be selected as indicator crops in economic compensation assessments in the important grain production zone. Economic compensation may be implemented by creating funds to update water-saving measures in agricultural facilities.

  12. Web/smart phone based control and feedback systems for irrigation systems

    Science.gov (United States)

    The role of the internet and mobile devices in the control and feedback of irrigation systems is reviewed. This role is placed in the larger context of four distinct components required for irrigation management, including 1. the control panel; 2. remote control; 3. soil, plant, and weather (SPW) se...

  13. Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China

    International Nuclear Information System (INIS)

    Khan, S.; Cao, Q.; Zheng, Y.M.; Huang, Y.Z.; Zhu, Y.G.

    2008-01-01

    Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (P ≤ 0.001) than in plants grown in the reference soil, and exceeded the permissible limits set by the State Environmental Protection Administration (SEPA) in China and the World Health Organization (WHO). Furthermore, this study highlights that both adults and children consuming food crops grown in wastewater-irrigated soils ingest significant amount of the metals studied. However, health risk index values of less than 1 indicate a relative absence of health risks associated with the ingestion of contaminated vegetables. - Long-term wastewater irrigation leads to buildup of heavy metals in soils and food crops

  14. Smart Water Conservation System for Irrigated Landscape

    Science.gov (United States)

    2016-05-01

    controllers, centralized and site-specific sensor inputs, leak detection sensors, and the use of harvested water (i.e., rainwater and air condition water ...include ET functionality with soil moisture sensor, and leak detection via flow meter. ESTCP Final Report Smart Water Conservation System 58... leakage . The minimum static pressure was not achieved because tank water levels were less than 10 feet in the selected low profile tank.) Adjust break

  15. Smart Water Conservation System for Irrigated Landscape

    Science.gov (United States)

    2016-05-01

    ht ly M or e W or kl oa d; 5 -M or e W or kl oa d; 6 -S ig ni fic an lty M or...install the water harvesting and pump system was captured from the contractor cost proposal. 7.1.3 Water Cost Water purchased from the Port Hueneme Water...818) 737-2734 KDuke@valleycrest.com Contractor Tom Santoianni 1205 Mill Rd. Bldg. 1430 Public Works, Ventura (805) 982-4075 Tom.Santoianni@navy.mil Energy Manager

  16. Quantitative Analysis on the Influence Factors of the Sustainable Water Resource Management Performance in Irrigation Areas: An Empirical Research from China

    Directory of Open Access Journals (Sweden)

    Hulin Pan

    2018-01-01

    Full Text Available Performance evaluation and influence factors analysis are vital to the sustainable water resources management (SWRM in irrigation areas. Based on the objectives and the implementation framework of modern integrated water resources management (IWRM, this research systematically developed an index system of the performances and their influence factors ones of the SWRM in irrigation areas. Using the method of multivariate regression combined with correlation analysis, this study estimated quantitatively the effect of multiple factors on the water resources management performances of irrigation areas in the Ganzhou District of Zhangye, Gansu, China. The results are presented below. The overall performance is mainly affected by management enabling environment and management institution with the regression coefficients of 0.0117 and 0.0235, respectively. The performance of ecological sustainability is mainly influenced by local economic development level and enable environment with the regression coefficients of 0.08642 and −0.0118, respectively. The performance of water use equity is mainly influenced by information publicity, administrators’ education level and ordinary water users’ participation level with the correlation coefficients of 0.637, 0.553 and 0.433, respectively. The performance of water use economic efficiency is mainly influenced by the management institutions and instruments with the regression coefficients of −0.07844 and 0.01808, respectively. In order to improve the overall performance of SWRM in irrigation areas, it is necessary to strengthen the public participation, improve the manager’ ability and provide sufficient financial support on management organization.

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

    Directory of Open Access Journals (Sweden)

    Kadbhane Sharad J.

    2017-03-01

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

  18. Go Grey - A Laundry to Landscape Irrigation System

    Science.gov (United States)

    Rajmohan, S.

    2017-12-01

    California residents have dealt with severe drought and high water bills for the few past years[1]. The objective of our project is to use the concept of greywater irrigation to build a low cost, adaptable, and easy to install irrigation system to collect the greywater from the washing machine and use it to water the plants. This system can reduce a household's water usage, extend the life of a septic system, and save time on watering plants by recycling the water from the washing machine. Our simple system requires PVC pipes, a three-way water diverter (valve), a mesh coffee filter, and a water (rain) barrel. The water from the washing machine travels through the three-way valve, which diverts it either to the garden or to the sewer. The PVC pipes lead outside to the garden, where the water barrel is located. The water goes through the mesh coffee filter that is attached on top of the barrel, so that lint and other impurities can be filtered out. The water collected in the barrel will travel through drip irrigation or through a hose to directly water the roots of the plants. This fully functional greywater system was successfully constructed and tested through various trails. We used a Kenmore standard 4.5 cubic feet front load high efficiency washer which uses less water compared to the traditional washers and measured the water collected in water barrel after each wash. Irrespective of the size of the load, the amount of water collected from each wash remained almost the same.. However, we collected enough grey water from each washer load to fill the rain barrel and water the plants in the garden. We were able apply the concept of greywater irrigation successfully to build our own low cost, adaptable, and easy to install greywater system that can be used in any household to water plants in the garden. Our system recycles the water from the washer instead of just wasting it thereby reducing a household's water usage and water bill especially during the time of

  19. On the waterfront : water distribution, technology and agrarian change in a South Indian canal irrigation system

    OpenAIRE

    Mollinga, P.P.

    1998-01-01

    This book discusses water distribution in the Tungabhadra Left Bank Canal irrigation system in Raichur district, Karnataka, India. The system is located in interior South India, where rainfall is limited (approximately 600 mm annually) and extremely variable. The region suffered from failed harvests and famines in the past. A large scale irrigation system was constructed to solve these problems. The system is operational since 1953 and was completed in 1968. The area to be irrigated ...

  20. Real-time drought forecasting system for irrigation managment

    Science.gov (United States)

    Ceppi, Alessandro; Ravazzani, Giovanni; Corbari, Chiara; Masseroni, Daniele; Meucci, Stefania; Pala, Francesca; Salerno, Raffaele; Meazza, Giuseppe; Chiesa, Marco; Mancini, Marco

    2013-04-01

    In recent years frequent periods of water scarcity have enhanced the need to use water more carefully, even in in European areas traditionally rich of water such as the Po Valley. In dry periods, the problem of water shortage can be enhanced by conflictual use of water such as irrigation, industrial and power production (hydroelectric and thermoelectric). Further, over the last decade the social perspective on this issue is increasing due to climate change and global warming scenarios which come out from the last IPCC Report. The increased frequency of dry periods has stimulated the improvement of irrigation and water management. In this study we show the development and implementation of the real-time drought forecasting system Pre.G.I., an Italian acronym that stands for "Hydro-Meteorological forecast for irrigation management". The system is based on ensemble prediction at long range (30 days) with hydrological simulation of water balance to forecast the soil water content in every parcel over the Consorzio Muzza basin. The studied area covers 74,000 ha in the middle of the Po Valley, near the city of Lodi. The hydrological ensemble forecasts are based on 20 meteorological members of the non-hydrostatic WRF model with 30 days as lead-time, provided by Epson Meteo Centre, while the hydrological model used to generate the soil moisture and water table simulations is the rainfall-runoff distributed FEST-WB model, developed at Politecnico di Milano. The hydrological model was validated against measurements of latent heat flux and soil moisture acquired by an eddy-covariance station. Reliability of the forecasting system and its benefits was assessed on some cases-study occurred in the recent years.

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

    Directory of Open Access Journals (Sweden)

    Rai Harminder K

    2005-08-01

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

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

    OpenAIRE

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

    2018-01-01

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

  3. Contamination of Phthalate Esters (PAEs in Typical Wastewater-Irrigated Agricultural Soils in Hebei, North China.

    Directory of Open Access Journals (Sweden)

    Yuan Zhang

    Full Text Available The Wangyang River (WYR basin is a typical wastewater irrigation area in Hebei Province, North China. This study investigated the concentration and distribution of six priority phthalate esters (PAEs in the agricultural soils in this area. Thirty-nine soil samples (0-20 cm were collected along the WYR to assess the PAE residues in soils. Results showed that PAEs are ubiquitous environmental contaminants in the topsoil obtained from the irrigation area. The concentrations of Σ6PAEs range from 0.191 μg g-1 dw to 0.457 μg g-1 dw with an average value of 0.294 μg g-1 dw. Di(2-ethylhexyl phthalate (DEHP and di-n-butyl phthalate (DnBP are the dominant PAE species in the agricultural soils. Among the DEHP concentrations, the highest DEHP concentration was found at the sites close to the villages; this result suggested that dense anthropogenic activities and random garbage disposal in the rural area are possible sources of PAEs. The PAE concentrations were weakly and positively correlated with soil organic carbon and soil enzyme activities; thus, these factors can affect the distribution of PAEs. This study further showed that only dimethyl phthalate (DMP concentrations exceeded the recommended allowable concentrations; no remediation measures are necessary to control the PAEs in the WYR area. However, the PAEs in the topsoil may pose a potential risk to the ecosystem and human health in this area. Therefore, the exacerbating PAE pollution should be addressed.

  4. Automatic aeroponic irrigation system based on Arduino’s platform

    Science.gov (United States)

    Montoya, A. P.; Obando, F. A.; Morales, J. G.; Vargas, G.

    2017-06-01

    The recirculating hydroponic culture techniques, as aeroponics, has several advantages over traditional agriculture, aimed to improve the efficiently and environmental impact of agriculture. These techniques require continuous monitoring and automation for proper operation. In this work was developed an automatic monitored aeroponic-irrigation system based on the Arduino’s free software platform. Analog and digital sensors for measuring the temperature, flow and level of a nutrient solution in a real greenhouse were implemented. In addition, the pH and electric conductivity of nutritive solutions are monitored using the Arduino’s differential configuration. The sensor network, the acquisition and automation system are managed by two Arduinos modules in master-slave configuration, which communicate one each other wireless by Wi-Fi. Further, data are stored in micro SD memories and the information is loaded on a web page in real time. The developed device brings important agronomic information when is tested with an arugula culture (Eruca sativa Mill). The system also could be employ as an early warning system to prevent irrigation malfunctions.

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

    Directory of Open Access Journals (Sweden)

    N. Ashrafi

    2016-02-01

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

  6. The Application of Drip Irrigation System on Tomato (Lycopersicum Esculentum Mill)

    OpenAIRE

    Setyaningrum, Diah Ayu

    2014-01-01

    This study aimed to analyze the performance of drip irrigation systems, determine performance of tomato treated under the irrigation systems.Field research was conducted at the Laboratory of Land and Water Resources Engineering; and at the Laboratory ofintegrated field, Faculty of Agriculture, University of Lampung in August 2013 to December 2013.Irrigation systems consisted of main componens: water supplies, Polythilene lateral tube, and emitters. Emitter on every pot, were made of Polythile...

  7. An analysis of solar energy and irrigation systems in Turkey

    International Nuclear Information System (INIS)

    Senol, Ramazan

    2012-01-01

    Pumping water is considered a common need all around the world. Standalone PV technologies are being increasingly used for midsize pumping applications. PV powered pumping systems offer simplicity, reliability, and low maintenance for irrigation systems. PV powered pump is particularly appropriate for water supply in remote areas where no electricity grid is available. In this paper, the technical and economical feasibility of photovoltaic pumping of water in Turkey has been studied. Here, the study has focused on small and medium-size mobile applications using energy and water-conserving forms of drip irrigation to apple orchard on up to 0.5 ha of land in Eğirdir District. Life cycle cost (LCC) method has been applied to determine the economic life of the PV modules, and the diesel pumping in Turkey taken as 25 years. - Highlights: ► In this paper, a water pumping system with mobile PV power station examined. ► The technical and economical feasibility of photovoltaic pumping in Turkey was studied. ► Here the study focused on small and medium-size mobile applications. ► LCC method applied to determine the economic life of the PV modules, and the diesel pumping in Turkey.

  8. Oasis Irrigation-Induced Hydro-Climatic Effects: A Case Study in the Hyper-Arid Region of Northwest China

    Directory of Open Access Journals (Sweden)

    Nan Shan

    2018-04-01

    Full Text Available The response of potential evapotranspiration (ET0 to widespread irrigation is important to fully understand future regional climate changes and to infer adaptive management of agricultural water resources. The quantitative impact of irrigation on ET0 from 1960 to 2013 was evaluated using historical time series data of daily meteorological observations in the hyper-arid region of northwest China. The decreasing trends in ET0 were accelerated for meteorological stations in regions with oasis agriculture, especially in the summer and during the growing season. Irrigation led to a cooling effect on temperature, increased relative humidity and precipitation. All of these changes contributed to a larger decrease of ET0 trend. The findings of this study advance our insight into the effects of irrigation on dynamics in ET0 and meteorological factors. Further investigations to understand how ET0 responds to climate change and agricultural irrigation could provide guidance for determining effective measures of water resources for adapting to global change.

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

    Science.gov (United States)

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

    2010-01-01

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

  10. Evaluation of crop production, trade, and consumption from the perspective of water resources: a case study of the Hetao irrigation district, China, for 1960-2010.

    Science.gov (United States)

    Liu, Jing; Sun, Shikun; Wu, Pute; Wang, Yubao; Zhao, Xining

    2015-02-01

    The integration of water footprints and virtual water flows allows the mapping of the links between production, trade, and consumption and could potentially help to alleviate water scarcity and improve water management. We evaluated the water footprints and virtual water flows of crop production, consumption, and trade and their influencing factors in the Hetao irrigation district in China for 1960-2010. The water footprint of crop production and the export of virtual water fluctuated but tended to increase during this period and were influenced mainly by agricultural factors such as crop yield, irrigation efficiency, and area sown. The water footprint of crop consumption and the import of virtual water increased during 1960-1979 and decreased during 1980-2010 and were influenced by socio-economic factors such as total population, the retail-price index, and the proportion of the population in urban areas. Most of the water footprint of production was exported to other areas, which added to the pressure on local water systems. The import of virtual water led to a saving of water for the Hetao irrigation district, while its share of the water footprint of consumption has decreased significantly since 1977. An increase in irrigation efficiency can alleviate water scarcity, and its application should be coupled with measures that constrain the continued expansion of agriculture. Full-cost pricing of irrigation water was an effective policy tool for its management. Re-shaping regional water-production and water-trade nexuses by changing crop structures could provide alternative opportunities for addressing the problems of local water scarcity, but the trade-offs involved should first be assessed. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    JI Xi-bin; KANG Er-si; CHEN Ren-sheng; ZHAO Wen-zhi; XIAO Sheng-chun; JIN Bo-wen

    2006-01-01

    Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year (2003), the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.

  12. A comprehensive guide for designing more efficient irrigation systems with respect to application control

    Science.gov (United States)

    Khaddam, Issam; Schuetze, Niels

    2017-04-01

    The worldwide water scarcity problems are expected to aggravate due to the increasing population and the need to produce more food. Irrigated agriculture is considered the highest consumer of fresh water resources with a rate exceeds 70% of global consumption. Consequently, an improvement in the efficiency of all irrigation methods, such as furrow or drip irrigation, becomes more necessary and urgent. Therefore, a more precise knowledge about soil water distribution in the root zone and the water balance components is required. For this purpose and as a part of the SAPHIR project (Saxonian Platform for high Performance Irrigation), a 2D simulation- based study was performed with virtual field conditions. The study investigates the most important design parameters of many irrigation systems, such as irrigation intensity and duration, and shows there influence on the water distribution efficiency. Furthermore, three main soil textures are used to test the impact of the soil hydraulic properties on irrigation effectiveness. A numerous number of irrigation scenarios of each irrigation system was simulated using HYDRUS 2D. Thereafter, the results were digitally calculated, compiled and made available online in the so called "Irrigation Atlases". The irrigation atlases provide graphical results of the soil moisture and pressure head distributions in the root zone. Moreover, they contain detailed information of the water balance for all simulated scenarios. The most studies evaluate the irrigation water demands on local, regional or global scales and for that an efficient water distribution is required. In this context, the irrigation atlases can serve as a valuable tool for the implementation of planned irrigation measures.

  13. Irrigation Water Availability and Winter Wheat Abandonment in the North China Plain (NCP: Findings from a Case Study in Cangxian County of Hebei Province

    Directory of Open Access Journals (Sweden)

    Xue Wang

    2018-01-01

    Full Text Available The North China Plain (NCP is the major winter wheat producing area in China. Abandonment of this crop has, however, become more and more prevalent in this region since the late 1990s. Although the underlying causes of this phenomenon remain little understood, irrigation water availability (IWA has always been regarded as the key factor limiting winter wheat production on the NCP. The aim of this paper is to determine the role played by IWA in the abandonment of winter wheat, using evidence drawn from a case study in Cangxian County, Hebei Province. First-hand data were collected for this study from 350 households in 35 villages, using semistructured one-on-one questionnaires. Five types of irrigation water sources were defined and identified at the level of individual land plots: “ground and surface water”, “just groundwater”, “just rivers”, “just reservoirs”, and “no irrigation”. These levels correspond to a decreasing trend in the overall frequency of irrigation and thus provide a clear proxy indicator for IWA. The results from a series of multilevel multinomial models show that the higher the IWA, the less likely it is for a land plot to abandon winter wheat. Specifically, using “no irrigation” cases as a control group, the results show that land plots with more sources of irrigation water also tend to be characterized by greater IWA, including “ground and surface water” and “just groundwater”, and also have lower probabilities of abandoning winter wheat. In contrast, land plots with less IWA (less irrigation water sources, including “just reservoirs” and “just rivers”, are more likely to abandon winter wheat. The results also show that, in addition to IWA, soil quality and plot size at the plot level, as well as demographic characteristics, farm equipment, and land fragmentation at the household level and irrigation prices at the village level, all play additional significant roles in the cropping-system

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

    Science.gov (United States)

    Shchedrin, V. N.

    2016-02-01

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

  15. A review of sustainable solar irrigation systems for Sub-Saharan Africa

    OpenAIRE

    Mohammed Wazed, S.; Hughes, B.R.; O’Connor, D.; Kaiser Calautit, J.

    2018-01-01

    This investigation focused on the research undertaken on solar photovoltaic (PV) and solar thermal technologies for pumping water generally for irrigation of remote rural farms specifically considering the Sub-Saharan African region. Solar PV systems have been researched extensively for irrigation purposes due to the rise in Oil prices and the upscaling in commercialisation of PV technology. Based on the literature the most effective PV system is presented for the irrigation of a small scare ...

  16. Crop and Irrigation Management Systems under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Pedro García-Caparrós

    2018-01-01

    Full Text Available Plants of Ruscus aculeatus, known as “butcher’s broom”, Maytenus senegalensis, known as “confetti tree”, and Juncus acutus, known as “spiny rush” were grown in pots with a mixture of sphagnum peat-moss and Perlite in order to determine the effect and evolution over time of three water use systems on plant growth, water saving and nutrient uptake. These were an open system (irrigated with standard nutrient solution and two closed systems (blended-water (drainage water blended with water of low electrical conductivity (EC and sequential reuse of drainage (sequential-reuse water, over a period of 8 weeks. Irrigation with blended- and sequential-reuse-water increased the biomass of all three species at the end of the experiment, compared to the open system. Overall, sequential-reuse-water treatment maximised biomass production. The application of blended- and sequential-reuse-water allowed savings of 17% of water in comparison to the open system. Regarding Cl, NO3− and H2PO4− loads, there was a removal of 5%, 32% and 32%; respectively in the blended-water treatment and 15%, 17% and 17% in the sequential-reuse water treatment compared to the open system. For the cation loads (Na+, K+, Ca2+ and Mg2+ in these water treatments there was a removal of 10%, 32%, 7% and 18% respectively in the blended-water treatment, and 17%, 22%, 17% and 18% respectively in the sequential-reuse treatment, compared to the open system.

  17. Carbon balance of a plastic mulch and drip irrigated cotton field in an arid oasis of Northwest China

    Science.gov (United States)

    Ming, G.

    2017-12-01

    Carbon balance of a plastic mulch and drip irrigated cotton field in an arid oasis of Northwest ChinaGuanghui Ming1, Fuqiang Tian1*, Hongchang Hu11State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, China,Abstracts: Agricultural ecosystems have the potential to offset rising CO2 concentration in the atmosphere but the potential is often altered by agricultural management. Plastic film mulching and drip irrigation (PMDI) have been widespread for saving water and improving crop yield worldwide. To comprehensively assess the carbon balance and to detect the controlling factors of the carbon flux in a PMDI cotton field, experiments combining eddy covariance (EC) system, chamber method and crop sampling were implemented in an arid oasis of Xinjiang from the year 2012 to 2016. The annual net ecosystem exchange (NEE) was -250.18 ± 80.41 g C m-2 in the five years, which indicated that the filed was a much stronger carbon sink. After removal of the harvest of cotton as seed oil (Ch) of 108.81±7.57 g C m-2, the field was still a moderate carbon sink with net biome productivity (NBP) of 141.37±73.7 g C m-2. Soil temperature can explain 82% of seasonal variation of nighttime NEE while PAR can explain 36-81% of daytime NEE varying with crop development and photosynthetic activity. NEE was separated into total ecosystem respiration (Reco, 1214.20±144.42 g C m-2) and gross primary productivity (GPP, 1464.38±122.78 g C m-2). Interannual Reco changed more drastically than GPP and respiration may be the main determinant of carbon balance in the PMDI field. Seasonal NPP measured by cop sampling method (NPPCS) agreed well with NPP calculated with EC (NPPEC), with the annual NPP of 708.86 ± 52.26 g C m-2, which indicated that our carbon flux measurements and separating methods reasonable. The PMDI cotton field induced more GPP and Reco than other croplands with larger light use efficiency (LUE) but relatively

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

    Science.gov (United States)

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

    2009-04-01

    The safe use of treated domestic wastewater for irrigation needs to address the risks for humans (workers, exposed via contact with irrigation water, soil, crops and food, consumers, exposed via ingestion of fresh and processed food), for animals (via ingestion of crops an soil), for the crops and agricultural productivity (via salinity and trace element uptake), for soil (via accumulation or release of pollutants) as well as for surface, groundwaters and the associated ecosystems (via runoff and infiltration, Kass et al., 2005, Bouwer, 2000). A work package in the EU FP5 project SAFIR is dedicated to study the impact of wastewater irrigation on the soil-water-plant-product system. Its monitoring program comprises pathogens and inorganic pollutants, including both geogenic and potentially anthropogenic trace elements in the aim to better understand soil-irrigation water interactions. The SAFIR field study sites are found in China, Italy, Crete, and Serbia. A performance evaluation of SAFIR-specific treatment technology through the monitoring of waste water and irrigation water quality was made through waste water chemical and microbiological qualities, which were investigated upstream and downstream of the SAFIR specific treatment three times per season. Irrigation water transits through the uppermost soil decimetres to the crop roots. The latter will become, in the course of the irrigation season, the major sink of percolating water, together with evaporation. The water saving irrigation techniques used in SAFIR are surface and subsurface drip irrigation. The investigation of the solid soil phase concentrates on the root zone as main transit and storage compartment for pollutants and, eventually, pathogens. The initial soil quality was assessed through a sampling campaign before the onset of the first year irrigation; the soil quality has been monitored throughout three years under cultivation of tomatoes or potatoes. The plot layout for each of the study sites

  19. Thermal Study on Extensive Green Roof Integrated Irrigation in Northwestern Arid Regions of China

    Directory of Open Access Journals (Sweden)

    Yajun Wang

    2017-11-01

    Full Text Available Selection of xerophils and drought tolerant plants is highly crucial in green roof techniques in the drought prone regions of Northwest China. In this study, the thermal performance under the natural conventional climate in summer was analyzed using a self-made simulation experimental platform through comparison of the internal surface temperature with and without green roofs. The distribution frequency of internal surface temperature was investigated by dividing internal surface temperature into several ranges. Statistical analysis showed that the frequency of internal surface temperature lower than 33 °C for green roofs was 91.8%, about 1.09 times higher than that for non-green roofs, and that the sum of internal surface temperature exceeding 35 °C was about one third of that for non-green roofs. The results proved that green roofs have a significant insulation effect. Moreover, the thermal insulation property of green roofs had a strong positive relation with outside temperature. The thermal insulation characteristic was improved as the outdoor temperature increased, additionally, it had a better insulation effect within two hours after irrigation.

  20. Projected energy and water consumption of Pacific Northwest irrigation systems

    Energy Technology Data Exchange (ETDEWEB)

    King, L. D.; Hellickson, M. L.; Schmisseur, W. E.; Shearer, M. N.

    1978-10-01

    A computer model has been developed to predict present and future regional water, energy, labor, and capital requirements of irrigated agricultural production in Idaho, Oregon, and Washington. The energy requirements calculated were on-farm pumping, and total energies. Total energies are the combined energies of on-farm pumping, manufacture, and installation. Irrigation system selections and modifications were based on an economic analysis utilizing the following input parameters: water, energy, labor, and capital costs and requirements; groundwater and surface water pumping lifts; improved application efficiencies; and pumping plant efficiencies. Major conclusions and implications of this analysis indicate that: as water application efficiencies increases additional quantities of water will not become available to other users; an overall increase in water application efficiencies resulted in decreases in gross water applications and increases in overall on-farm pumping and total energy consumptions; more energy will be consumed as pumping and total energies than will be conserved through decreased diversion pumping energy requirements; pump-back and similar technologies have the potential of both increasing application efficiencies and energy conservation; and the interrelationships understood between applying water in quantities greater than required for crop consumptive use and leaching, and late season in-steam flow augmentation and/or aquifer recharge are not well understood, and sound policy decisions concerning agricultural use of water and energy cannot be made until these interrelationships are better understood.

  1. Computer-Aided Design System Development of Fixed Water Distribution of Pipe Irrigation System

    OpenAIRE

    Zhou , Mingyao; Wang , Susheng; Zhang , Zhen; Chen , Lidong

    2010-01-01

    International audience; It is necessary to research a cheap and simple fixed water distribution device according to the current situation of the technology of low-pressure pipe irrigation. This article proposed a fixed water distribution device with round table based on the analysis of the hydraulic characteristics of low-pressure pipe irrigation systems. The simulation of FLUENT and GAMBIT software conducted that the flow of this structure was steady with a low head loss comparing to other t...

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

    NARCIS (Netherlands)

    Pant, D.R.

    2000-01-01

    With the support from various donors, His Majesty's Government of Nepal has implemented support programmes with a view to transform water availability, improve production, and increase the institutional capabilities of farmers to develop and sustain efficient, fair and reliable irrigation

  3. Design and implementation of expert decision system in Yellow River Irrigation

    Science.gov (United States)

    Fuping, Wang; Bingbing, Lei; Jie, Pan

    2018-03-01

    How to make full use of water resources in the Yellow River irrigation is a problem needed to be solved urgently. On account of the different irrigation strategies in various growth stages of wheat, this paper proposes a novel irrigation expert decision system basing on fuzzy control technique. According to the control experience, expert knowledge and MATLAB simulation optimization, we obtain the irrigation fuzzy control table stored in the computer memory. The controlling irrigation is accomplished by reading the data from fuzzy control table. The experimental results show that the expert system can be used in the production of wheat to achieve timely and appropriate irrigation, and ensure that wheat growth cycle is always in the best growth environment.

  4. A comparative analysis of the impacts of climate change and irrigation on land surface and subsurface hydrology in the North China Plain

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-01

    The Community Land Model 4.0 (CLM4) was used to investigate and compare the effects of climate change and irrigation on terrestrial water cycle. Three climate change scenarios and one irrigation scenario (IRRIG) were simulated in the North China Plain (NCP), which is one of the most vulnerable regions to climate change and human perturbations in China. The climate change scenarios consist of (1) HOT (i.e. temperature increase by 2oC); (2) HOTWET (same with HOT but with an increase of precipitation by 15%); (3) HOTDRY (same with HOT but with a decrease of precipitation by 15%). In the IRRIG scenario, the irrigation scheme was calibrated to simulate irrigation amounts that match the actual irrigation amounts and irrigation was divided between surface water and groundwater withdrawals based on census data. Our results show that the impacts of climate change were more widespread while those of irrigation were concentrated only over the agricultural regions. Specifically, the mean water table depth was simulated to decline persistently by over 1 m annually due to groundwater exploitation during the period of 1980-2000, while much smaller effects were induced by climate change. Although irrigation has comparable effects on surface fluxes and surface soil moisture as climate change, it has much greater effects on water table depth and groundwater storage. Moreover, irrigation has much larger effects on the top layer soil moisture whereas increase in precipitation associated with climate change exerts more influence on lower layer soil moisture. This study emphasizes the need to accurately account for irrigation impacts in adapting to climate change.

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

    Science.gov (United States)

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

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

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

    Science.gov (United States)

    Malota, Mphatso; Mchenga, Joshua

    2018-03-01

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

  7. Comparative antibacterial efficacies of hydrodynamic and ultrasonic irrigation systems in vitro.

    Science.gov (United States)

    Cachovan, Georg; Schiffner, Ulrich; Altenhof, Saskia; Guentsch, Arndt; Pfister, Wolfgang; Eick, Sigrun

    2013-09-01

    To ensure root canal treatment success, endodontic microbiota should be efficiently reduced. The in vitro bactericidal effects of a hydrodynamic system and a passive ultrasonic irrigation system were compared. Single-rooted extracted teeth (n = 250) were contaminated with suspensions of Enterococcus faecalis ATCC 29212, mixed aerobic cultures, or mixed anaerobic cultures. First, the antibacterial effects of the hydrodynamic system (RinsEndo), a passive ultrasonic irrigation system (Piezo smart), and manual rinsing with 0.9% NaCl (the control) were compared. Colony-forming units were counted. Second, the 2 systems were used with 1.5% sodium hypochlorite (NaOCl) alone or NaOCl + 0.2% chlorhexidine (CHX). The colony-forming units in the treated and untreated roots were determined during a period of 5 days. Both irrigation systems reduced bacterial numbers more effectively than manual rinsing (P irrigation reduced bacterial counts significantly better than hydrodynamic irrigation (P = .042). The NaOCl + CHX combination was more effective than NaOCl alone for both systems (P irrigation was more effective with NaOCl + CHX than the passive ultrasonic irrigation system. Both irrigation systems, when combined with NaOCl + CHX, removed bacteria from root canals. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Moderate irrigation intervals facilitate establishment of two desert shrubs in the Taklimakan Desert Highway Shelterbelt in China.

    Science.gov (United States)

    Li, Congjuan; Shi, Xiang; Mohamad, Osama Abdalla; Gao, Jie; Xu, Xinwen; Xie, Yijun

    2017-01-01

    Water influences various physiological and ecological processes of plants in different ecosystems, especially in desert ecosystems. The purpose of this study is to investigate the response of physiological and morphological acclimation of two shrubs Haloxylon ammodendron and Calligonum mongolicunl to variations in irrigation intervals. The irrigation frequency was set as 1-, 2-, 4-, 8- and 12-week intervals respectively from March to October during 2012-2014 to investigate the response of physiological and morphological acclimation of two desert shrubs Haloxylon ammodendron and Calligonum mongolicunl to variations in the irrigation system. The irrigation interval significantly affected the individual-scale carbon acquisition and biomass allocation pattern of both species. Under good water conditions (1- and 2-week intervals), carbon assimilation was significantly higher than other treatments; while, under water shortage conditions (8- and 12-week intervals), there was much defoliation; and under moderate irrigation intervals (4 weeks), the assimilative organs grew gently with almost no defoliation occurring. Both studied species maintained similar ecophysiologically adaptive strategies, while C. mongolicunl was more sensitive to drought stress because of its shallow root system and preferential belowground allocation of resources. A moderate irrigation interval of 4 weeks was a suitable pattern for both plants since it not only saved water but also met the water demands of the plants.

  9. Gated or ungated : water control in government-built irrigation systems : comparative research in Nepal

    NARCIS (Netherlands)

    Pradhan, T.M.S.

    1996-01-01


    The control, allocation and distribution, of water is the core process of an irrigation system. It is the process by which the available water is divided and distributed to the smaller irrigation units within the system, which in turn is distributed further down to the individual water

  10. Developing a hybrid solar/wind powered irrigation system for crops in the Great Plains

    Science.gov (United States)

    Some small scale irrigation systems (powered by wind or solar do not require subsidies, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. By adding a solar-photovoltaic (PV) array together with a wind...

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

    Directory of Open Access Journals (Sweden)

    kourosh majdsalimi

    2016-02-01

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

  12. AgIIS, Agricultural Irrigation Imaging System, design and application

    Science.gov (United States)

    Haberland, Julio Andres

    Remote sensing is a tool that is increasingly used in agriculture for crop management purposes. A ground-based remote sensing data acquisition system was designed, constructed, and implemented to collect high spatial and temporal resolution data in irrigated agriculture. The system was composed of a rail that mounts on a linear move irrigation machine, and a small cart that runs back and forth on the rail. The cart was equipped with a sensors package that measured reflectance in four discrete wavelengths (550 nm, 660 nm, 720 nm, and 810 nm, all 10 nm bandwidth) and an infrared thermometer. A global positioning system and triggers on the rail indicated cart position. The data was postprocessed in order to generate vegetation maps, N and water status maps and other indices relevant for site-specific crop management. A geographic information system (GIS) was used to generate images of the field on any desired day. The system was named AgIIS (A&barbelow;gricultural I&barbelow;rrigation I&barbelow;maging S&barbelow;ystem). This ground based remote sensing acquisition system was developed at the Agricultural and Biosystems Engineering Department at the University of Arizona in conjunction with the U.S. Water Conservation Laboratory in Phoenix, as part of a cooperative study primarily funded by the Idaho National Environmental and Engineering Laboratory. A second phase of the study utilized data acquired with AgIIS during the 1999 cotton growing season to model petiole nitrate (PNO3 -) and total leaf N. A latin square experimental design with optimal and low water and optimal and low N was used to evaluate N status under water and no water stress conditions. Multivariable models were generated with neural networks (NN) and multilinear regression (MLR). Single variable models were generated from chlorophyll meter readings (SPAD) and from the Canopy Chlorophyll Content Index (CCCI). All models were evaluated against observed PNO3- and total leaf N levels. The NN models

  13. Understanding water delivery performance in a large-scale irrigation system in Peru

    NARCIS (Netherlands)

    Vos, J.M.C.

    2005-01-01

    During a two-year field study the performance of the water delivery was evaluated in a large-scale irrigation system on the north coast of Peru. Flow measurements were carried out along the main canals, along two secondary canals, and in two tertiary blocks in the Chancay-Lambayeque irrigation

  14. Nitrogen management impacts nitrous oxide emissions under varying cotton irrigation systems in the American Desert Southwest

    Science.gov (United States)

    Irrigation of food and fiber crops worldwide continues to increase. Nitrogen (N) from fertilizers is a major source of the potent greenhouse gas nitrous oxide (N2O) in irrigated cropping systems. Nitrous oxide emissions data are scarce for crops in the arid Western US. The objective of these studies...

  15. Bricolage as innovation: opening the black box of drip irrigation systems

    NARCIS (Netherlands)

    Benouniche, M.; Zwarteveen, M.; Kuper, M.

    2014-01-01

    In Morocco, many farmers enthusiastically use drip irrigation. However, few drip irrigation systems conform to engineering standards. In a process they refer to as bricolage, farmers modify and adapt standard designs, thus creating their own technical standards. We document three instances of

  16. Bricolage as innovation: opening the black box of Drip Irrigation Systems

    NARCIS (Netherlands)

    Benouniche, M.; Zwarteveen, M.Z.; Kuper, M.

    2014-01-01

    In Morocco, many farmers enthusiastically use drip irrigation. However, few drip irrigation systems conform to engineering standards. In a process they refer to as bricolage, farmers modify and adapt standard designs, thus creating their own technical standards. We document three instances of

  17. China's Innovation System

    DEFF Research Database (Denmark)

    Gu, Shulin; Schwaag Serber, Sylvia; Lundvall, Bengt-Åke

    2016-01-01

    In their 2006 article on innovation in China in this journal, Gu and Lundvall pointed to some weaknesses and challenges for China’s growth and they also outlined ideas for policy action to overcome those. In this short note, written in collaboration with Sylvia Schwag Serger, they go back...... and assess China's social and economic development in the 10 years that followed in the light of their original analysis of challenges and ideas for policy action...

  18. Effect of climate change on the irrigation and discharge scheme for winter wheat in Huaibei Plain, China

    Science.gov (United States)

    Zhu, Y.; Ren, L.; Lü, H.

    2017-12-01

    On the Huaibei Plain of Anhui Province, China, winter wheat (WW) is the most prominent crop. The study area belongs to transitional climate, with shallow water table. The original climate change is complex, in addition, global warming make the climate change more complex. The winter wheat growth period is from October to June, just during the rainless season, the WW growth always depends on part of irrigation water. Under such complex climate change, the rainfall varies during the growing seasons, and water table elevations also vary. Thus, water tables supply variable moisture change between soil water and groundwater, which impact the irrigation and discharge scheme for plant growth and yield. In Huaibei plain, the environmental pollution is very serious because of agricultural use of chemical fertilizer, pesticide, herbicide and etc. In order to protect river water and groundwater from pollution, the irrigation and discharge scheme should be estimated accurately. Therefore, determining the irrigation and discharge scheme for winter wheat under climate change is important for the plant growth management decision-making. Based on field observations and local weather data of 2004-2005 and 2005-2006, the numerical model HYDRUS-1D was validated and calibrated by comparing simulated and measured root-zone soil water contents. The validated model was used to estimate the irrigation and discharge scheme in 2010-2090 under the scenarios described by HadCM3 (1970 to 2000 climate states are taken as baselines) with winter wheat growth in an optimum state indicated by growth height and LAI.

  19. Greenhouse irrigation control system design based on ZigBee and fuzzy PID technology

    Science.gov (United States)

    Zhou, Bing; Yang, Qiliang; Liu, Kenan; Li, Peiqing; Zhang, Jing; Wang, Qijian

    In order to achieve the water demand information accurately detect of the greenhouse crop and its precision irrigation automatic control, this article has designed a set of the irrigated control system based on ZigBee and fuzzy PID technology, which composed by the soil water potential sensor, CC2530F256 wireless microprocessor, IAR Embedded Workbench software development platform. And the time of Irrigation as the output .while the amount of soil water potential and crop growth cycle as the input. The article depended on Greenhouse-grown Jatropha to verify the object, the results show that the system can irrigate timely and appropriately according to the soil water potential and water demend of the different stages of Jatropha growth , which basically meet the design requirements. Therefore, the system has broad application prospects in the amount of greenhouse crop of fine control irrigation.

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

    Science.gov (United States)

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

    2017-08-01

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

  1. Interactive effects of elevated CO2 concentration and irrigation on photosynthetic parameters and yield of maize in Northeast China.

    Directory of Open Access Journals (Sweden)

    Fanchao Meng

    Full Text Available Maize is one of the major cultivated crops of China, having a central role in ensuring the food security of the country. There has been a significant increase in studies of maize under interactive effects of elevated CO2 concentration ([CO2] and other factors, yet the interactive effects of elevated [CO2] and increasing precipitation on maize has remained unclear. In this study, a manipulative experiment in Jinzhou, Liaoning province, Northeast China was performed so as to obtain reliable results concerning the later effects. The Open Top Chambers (OTCs experiment was designed to control contrasting [CO2] i.e., 390, 450 and 550 µmol·mol(-1, and the experiment with 15% increasing precipitation levels was also set based on the average monthly precipitation of 5-9 month from 1981 to 2010 and controlled by irrigation. Thus, six treatments, i.e. C550W+15%, C550W0, C450W+15%, C450W0, C390W+15% and C390W0 were included in this study. The results showed that the irrigation under elevated [CO2] levels increased the leaf net photosynthetic rate (Pn and intercellular CO2 concentration (Ci of maize. Similarly, the stomatal conductance (Gs and transpiration rate (Tr decreased with elevated [CO2], but irrigation have a positive effect on increased of them at each [CO2] level, resulting in the water use efficiency (WUE higher in natural precipitation treatment than irrigation treatment at elevated [CO2] levels. Irradiance-response parameters, e.g., maximum net photosynthetic rate (Pnmax and light saturation points (LSP were increased under elevated [CO2] and irrigation, and dark respiration (Rd was increased as well. The growth characteristics, e.g., plant height, leaf area and aboveground biomass were enhanced, resulting in an improved of yield and ear characteristics except axle diameter. The study concluded by reporting that, future elevated [CO2] may favor to maize when coupled with increasing amount of precipitation in Northeast China.

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

    NARCIS (Netherlands)

    Parajuli, U.N.

    1999-01-01

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

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

    Directory of Open Access Journals (Sweden)

    rahim motalebifard

    2017-02-01

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

  4. Structuring properties of irrigation systems : Understanding relations between humans and hydraulics through modeling

    NARCIS (Netherlands)

    Ertsen, M.W.

    2010-01-01

    Irrigation systems were clearly important in ancient times in supplying crops with water. This requires physical distribution facilities and socio-political arrangements to coordinate between actors. Resulting systems are highly diverse, and are being studied extensively within archeology and

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

    Science.gov (United States)

    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.

  6. Estimation of soil salinity in a drip irrigation system by using joint inversion of multicoil electromagnetic induction measurements

    KAUST Repository

    Jadoon, Khan Zaib; Moghadas, Davood; Jadoon, Aurangzeb; Missimer, Thomas M.; Al-Mashharawi, Samir K.; McCabe, Matthew

    2015-01-01

    -Explorer) is used for subsurface characterization of soil salinity in a drip irrigation system via a joint inversion approach of multiconfiguration EMI measurements. EMI measurements were conducted across a farm where Acacia trees are irrigated with brackish water

  7. Ruling by canal: Governance and system-level design characteristics of large scale irrigation infrastructure in India and Uzbekistan

    NARCIS (Netherlands)

    Mollinga, P.; Veldwisch, G.J.A.

    2016-01-01

    This paper explores the relationship between governance regime and large-scale irrigation system design by investigating three cases: 1) protective irrigation design in post-independent South India; 2) canal irrigation system design in Khorezm Province, Uzbekistan, as implemented in the USSR period,

  8. Effect of different irrigation systems on root growth of maize and cowpea plants in sandy soil

    Directory of Open Access Journals (Sweden)

    Noha A. Mahgoub

    2017-10-01

    Full Text Available A field experiment was conducted at the Experimental Farm, Faculty of Agriculture, Suez Canal University to study the influence of different irrigation systems on root length density and specific root length of maize and cowpea plants cultivated in sandy soil. Three irrigation systems (Surface, drip and sprinkler irrigation were used in this study. The NPK fertilizers were applied as recommended doses for maize and cowpea. Root samples were collected from the soil profile below one plant (maize and cowpea which was irrigated by the three irrigation systems by using an iron box (30 cm× 20 cm which is divided into 24 small boxes each box is (5× 5 × 5 cm. At surface irrigation, root length density of cowpea reached to soil depth 30-40cm with lateral distances 5-10 cm and 15-20 cm. Vertical distribution of root length density of maize was increased with soil depth till 20-25 cm, and then it decreased till soil depth 35-40cm. Under drip irrigation, root length density of cowpea increased horizontally from 0-5cm to 10-15cm then it decreased till soil depth 25-30 cm and below this depth root length density disappeared. For the root length density and specific root length of maize under drip irrigation, the data showed that root length density and specific root length decreased with increasing in soil depth. The root length density of cowpea under sprinkler irrigation at 0-5cm disappeared from horizontal distance at 25-30 cm. The data showed that root length density of maize under sprinkler irrigation was higher at the soil top layers 0-5 cm and 5-10 cm than other layers from 10-40 cm.

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

    Directory of Open Access Journals (Sweden)

    Adriano da Silva Lopes

    2014-07-01

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

  10. Improvements in irrigation system modelling when using remotely sensed ET for calibration

    Science.gov (United States)

    van Opstal, J. D.; Neale, C. M. U.; Lecina, S.

    2014-10-01

    Irrigation system modelling is often used to aid decision-makers in the agricultural sector. It gives insight on the consequences of potential management and infrastructure changes. However, simulating an irrigation district requires a considerable amount of input data to properly represent the system, which is not easily acquired or available. During the simulation process, several assumptions have to be made and the calibration is usually performed only with flow measurements. The advancement of estimating evapotranspiration (ET) using remote sensing is a welcome asset for irrigation system modelling. Remotely-sensed ET can be used to improve the model accuracy in simulating the water balance and the crop production. This study makes use of the Ador-Simulation irrigation system model, which simulates water flows in irrigation districts in both the canal infrastructure and on-field. ET is estimated using an energy balance model, namely SEBAL, which has been proven to function well for agricultural areas. The seasonal ET by the Ador model and the ET from SEBAL are compared. These results determine sub-command areas, which perform well under current assumptions or, conversely, areas that need re-evaluation of assumptions and a re-run of the model. Using a combined approach of the Ador irrigation system model and remote sensing outputs from SEBAL, gives great insights during the modelling process and can accelerate the process. Additionally cost-savings and time-savings are apparent due to the decrease in input data required for simulating large-scale irrigation areas.

  11. Heavy Metal Residues in Soil and Accumulation in Maize at Long-Term Wastewater Irrigation Area in Tongliao, China

    Directory of Open Access Journals (Sweden)

    Yintao Lu

    2015-01-01

    Full Text Available Soil and plant samples were collected from Tongliao, China, during the maize growth cycle between May and October 2010. Heavy metals, such as Cr, Pb, Ni, and Zn, were analyzed. The concentrations of Cr, Pb, Ni, and Zn in the wastewater-irrigated area were higher than those in the topsoil from the groundwater-irrigated area. The concentrations of metals in the maize increased as follows: Pb < Ni < Zn < Cr. In addition, Cr, Pb, and Ni mainly accumulated in the maize roots, and Zn mainly accumulated in the maize fruit. The results of translocation factors (TF and bioconcentration factors (BCF of maize for heavy metals revealed that maize is an excluder plant and a potential accumulator plant and can serve as an ideal slope remediation plant. In addition, the increasing heavy metal contents in soils that have been polluted by wastewater irrigation must result in the accumulation of Cr, Pb, Ni, and Zn in maize. Thus, the pollution level can be decreased by harvesting and disposing of and recovering the plant material.

  12. Early irrigation systems in southeastern Arizona: the ostracode perspective

    Science.gov (United States)

    Palacios-Fest, Manuel R.; Mabry, Jonathan B.; Nials, Fred; Holmlund, James P.; Miksa, Elizabeth; Davis, Owen K.

    2001-10-01

    For the first time, the Early Agricultural Period (1200 BC-150 AD) canal irrigation in the Santa Cruz River Valley, southeastern Arizona, is documented through ostracode paleoecology. Interpretations based on ostracode paleoecology and taphonomy are supported by anthropological, sedimentological, geomorphological, and palynological information, and were used to determine the environmental history of the northern Tucson Basin during the time span represented by the sequence of canals at Las Capas (site AZ AA:12:753 ASM). We also attempt to elucidate based on archaeological artifacts if the Hohokam or a previous civilization built the canals. Between 3000 and 2400 radiocarbon years BP, at least three episodes of canal operation are defined by ostracode assemblages and pollen records. Modern (mid-late 20th century) canals supported no ostracodes, probably because of temporally brief canal operation from local wells. Three stages of water management are well defined during prehistoric canal operation. Ostracode faunal associations indicate that prehistoric peoples first operated their irrigation systems in a simple, 'opportunistic' mode (diversion of ephemeral flows following storms), and later in a complex, 'functional' mode (carefully timed diversions of perennial flows). The geomorphological reconstruction indicates that these canals had a minimum length of 1.1 km, and were possibly twice as long. The hydraulic reconstruction of these canals suggests that they had similar gradients (0.05-0.1%) to later prehistoric canals in the same valley. Discharges were also respectable. When flowing at bank-full, the largest canal provided an acre-foot of water in about 2.3 h; when flowing half-full (probably a more realistic assumption), it produced an acre-foot of water in about 8.6 h. Palynological records of the oldest canals (here identified as Features 3 and 4; 3000-2500 years BP) indicate they were used temporarily, since riparian vegetation did not grow consistently in

  13. The effect of four different irrigation systems in the removal of a root canal sealer.

    Science.gov (United States)

    Grischke, J; Müller-Heine, A; Hülsmann, M

    2014-09-01

    The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals. Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system. Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated. Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.

  14. Pollution of intensively managed greenhouse soils by nutrients and heavy metals in the Yellow River Irrigation Region, Northwest China.

    Science.gov (United States)

    Kong, Xiaole; Cao, Jing; Tang, Rangyun; Zhang, Shengqiang; Dong, Fang

    2014-11-01

    The present study aimed to assess the potential ecological risk of heavy metals and nutrient accumulation in polytunnel greenhouse soils in the Yellow River irrigation region (YRIR), Northwest China, and to identify the potential sources of these heavy metals using principal component analysis. Contents of available nitrogen (AN), phosphorus (AP), and potassium (AK) in the surface polytunnel greenhouse soils (0-20 cm) varied from 13.42 to 486.78, from 39.10 to 566.97, and from 21.64 to 1,156.40 mg kg(-1), respectively, as well as AP, soil organic matter (SOM) and AK contents tended to increase significantly at the 0-20- and 20-40-cm soil layers. Heavy metal accumulations occurred in the polytunnel greenhouse soils as compared to arable soils, especially at a depth of 20 cm where Cd, Zn and Cu contents were significantly higher than arable soil. Cd and As were found to be the two main polluting elements in the greenhouse soils because their contents exceeded the thresholds established for greenhouse vegetable production HJ333-2006 in China and the background of Gansu province. It has been shown that Cd, Cu, Pb and Zn at the 0-20-cm soil layer were derived mainly from agricultural production activities, whereas contents of Cr and Ni at the same soil layer were determined by 'natural' factors and As originated from natural sources, deposition and irrigation water.

  15. Design of Remote Monitoring System of Irrigation based on GSM and ZigBee Technology

    Science.gov (United States)

    Xiao xi, Zheng; Fang, Zhao; Shuaifei, Shao

    2018-03-01

    To solve the problems of low level of irrigation and waste of water resources, a remote monitoring system for farmland irrigation based on GSM communication technology and ZigBee technology was designed. The system is composed of sensors, GSM communication module, ZigBee module, host computer, valve and so on. The system detects and closes the pump and the electromagnetic valve according to the need of the system, and transmits the monitoring information to the host computer or the user’s Mobile phone through the GSM communication network. Experiments show that the system has low power consumption, friendly man-machine interface, convenient and simple. It can monitor agricultural environment remotely and control related irrigation equipment at any time and place, and can better meet the needs of remote monitoring of farmland irrigation.

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

    Science.gov (United States)

    Widiastuti, I.; Wijayanto, D. S.

    2017-03-01

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

  17. A catchment-scale irrigation systems model for sugarcane Part 1 ...

    African Journals Online (AJOL)

    2008-03-28

    Mar 28, 2008 ... Keywords: ACRUCane, irrigation systems, water management, crop modelling, hydrology, water ... vide all the necessary decision support information in an inte- .... Root growth is simulated using a methodology described by.

  18. Water sensors with cellular system eliminate tail water drainage in alfalfa irrigation

    Directory of Open Access Journals (Sweden)

    Rajat Saha

    2011-10-01

    Full Text Available Alfalfa is the largest consumer of water among all crops in California. It is generally flood-irrigated, so any system that decreases runoff can improve irrigation efficiency and conserve water. To more accurately manage the water flow at the tail (bottom end of the field in surface-irrigated alfalfa crops, we developed a system that consists of wetting-front sensors, a cellular communication system and a water advance model. This system detects the wetting front, determines its advance rate and generates a cell-phone alert to the irrigator when the water supply needs to be cut off, so that tail water drainage is minimized. To test its feasibility, we conducted field tests during the 2008 and 2009 alfalfa growing seasons. The field experiments successfully validated the methodology, producing zero tail water drainage.

  19. Optimal design of pressurized irrigation systems. Application cases (Ecuador

    Directory of Open Access Journals (Sweden)

    Carmen Mireya Lapo Pauta

    2013-05-01

    Full Text Available This paper presents research completed with the intention of finding the most economical solution in the design of pressurized irrigation networks, while efficiently meet service delivery. A systematic methodology is proposed that combines two optimization techniques through a “hybrid method” in, which linear programming, nonlinear programming and genetic algorithms are fused. The overall formulations of the problem of optimal dimensioning consist of minimizing an objective function constituted through the associated cost of the pipes that form the network. This methodology was implemented in three networks a fictitious irrigation and two irrigation networks (Tuncarta and Cariyacu located in the cities of Loja and Chimborazo which yielded optimal design  solutions. Finally different scenarios were simulated in both models to obtain an overview of the operation of the hydraulic variables

  20. Nitrogen dynamics in the soil-plant system under deficit and partial root-zone drying irrigation strategies in potatoes

    DEFF Research Database (Denmark)

    Shahnazari, Ali; Ahmadi, Seyed Hamid; Lærke, Poul Erik

    2008-01-01

    Experiments were conducted in lysimeters with sandy soil under an automatic rain-out shelter to study the effects of subsurface drip irrigation treatments, full irrigation (FI), deficit irrigation (DI) and partial root-zone drying (PRD), on nitrogen (N) dynamics in the soil-plant system of potatoes...

  1. Novel approach to evaluate the dynamic variation of wind drift and evaporation losses under moving irrigation systems

    Science.gov (United States)

    Sayed-Hossein Sadeghi; Troy R. Peters; Mohammad Z. Amini; Sparkle L. Malone; Hank W. Loescher

    2015-01-01

    The increased need for water and food security requires the development of new approaches to save water through irrigation management strategies, particularly for center pivot irrigation. To do so entails monitoring of the dynamic variation in wind drift and evaporation losses (WDELs) of irrigation systems under different weather conditions and for relatively long time...

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

    Directory of Open Access Journals (Sweden)

    Sotirios Kontogiannis

    2017-11-01

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

  3. A compact to revitalise large-scale irrigation systems: A ‘theory of change’ approach

    Directory of Open Access Journals (Sweden)

    Bruce A. Lankford

    2016-02-01

    Full Text Available In countries with transitional economies such as those found in South Asia, large-scale irrigation systems (LSIS with a history of public ownership account for about 115 million ha (Mha or approximately 45% of their total area under irrigation. In terms of the global area of irrigation (320 Mha for all countries, LSIS are estimated at 130 Mha or 40% of irrigated land. These systems can potentially deliver significant local, regional and global benefits in terms of food, water and energy security, employment, economic growth and ecosystem services. For example, primary crop production is conservatively valued at about US$355 billion. However, efforts to enhance these benefits and reform the sector have been costly and outcomes have been underwhelming and short-lived. We propose the application of a 'theory of change' (ToC as a foundation for promoting transformational change in large-scale irrigation centred upon a 'global irrigation compact' that promotes new forms of leadership, partnership and ownership (LPO. The compact argues that LSIS can change by switching away from the current channelling of aid finances controlled by government irrigation agencies. Instead it is for irrigators, closely partnered by private, public and NGO advisory and regulatory services, to develop strong leadership models and to find new compensatory partnerships with cities and other river basin neighbours. The paper summarises key assumptions for change in the LSIS sector including the need to initially test this change via a handful of volunteer systems. Our other key purpose is to demonstrate a ToC template by which large-scale irrigation policy can be better elaborated and discussed.

  4. quixotic coupling between irrigation system and maize-cowpea

    African Journals Online (AJOL)

    ACSS

    number row-1 and maize grain yield, respectively. The ridge ... Key Words: Furrow irrigation, water use efficiency, Zea mays. RÉSUMÉ ... important in arid and semi-arid regions, with ... as maize) canopy is not able to intercept all the solar radiation during the growth period. ... Intercropping maize and legumes considerably ...

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

    Directory of Open Access Journals (Sweden)

    Daniele Masseroni

    2017-01-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  7. Sweet sorghum performance under irrigated conditions in northwest China : Biomass and its partitioning in inbred and hybrid cultivars at two nitrogen levels

    NARCIS (Netherlands)

    Fan, F.; Spiertz, J.H.J.; Han, L.P.; Liu, Z.X.; Xie, G.H.

    2013-01-01

    Effects of cultivar choice and nitrogen supply on biomass yield and dry matter partitioning of sweet sorghum [Sorghum bicolor (L.) Moench] were studied under irrigated conditions in the arid temperate climate of north-west China. Two hybrid cultivars, Zaoshu-1 (ZS 1) and Chuntian-2 (CT 2), and two

  8. Participatory Rural Appraisal for Diagnostic Analysis of spate irrigation systems in Raya Valley, Ethiopia

    Directory of Open Access Journals (Sweden)

    Giulio Castelli

    2017-05-01

    Full Text Available Spate irrigation is a complex and unique form of water management, which represent the main source of irrigation water in semi-arid river catchments. Water is diverted from seasonal rivers by using diversion structures made by stones, earth and brushwood, located within the river bed. The modernisation of spate irrigation realised in Raya Valley (northern Ethiopia resulted in disappointing performances. One of the main reasons for this failure was the poor consideration of the characteristics of seasonal catchments and local communities’ needs and preferences. Local farmers, who showed a deep knowledge of the river system, were involved only at the level of consultation. The aim of this research was to develop a participatory Diagnostic Analysis (DA for a traditional non-modernised spate irrigation system in Raya Valley, in order to involve local farmers within the development process, and to build a solid knowledge basis for effective improvements. A Participatory Rural Appraisal (PRA of the Harosha spate irrigation system was undertaken. PRA techniques focusing on spatial, temporal, socio-economical and spatiotemporal aspects of the system were performed with local farmers in order to identify and rank main problems and constraints to development. Farmers recognised the need of more resistant diversion structures and gabion walls for the stabilisation of the river bank. The involvement of farmers also helped to highlight that not only irrigation-related problems, but also flood-related problems threaten agricultural production and rural livelihoods. Rather than an irrigation system approach, an approach integrating irrigation development and flood risk mitigation is suggested for framing future development strategies.

  9. Using hydraulic modeling to simulate human interactions with water resources in an Omani irrigation system

    Science.gov (United States)

    Xanthopoulou, Themis; Ertsen, Maurits; Düring, Bleda; Kolen, Jan

    2017-04-01

    In the dry Southern Oman, more than a thousand years ago, a large water system that connected the mountain mass with the coastal region was constructed. Its length (up to 30 km) and the fact that the coastal region has a rich groundwater aquifer create confusion as to why the system was initially built. Nonetheless, it was abandoned a couple of centuries later only to be partially revived by small farming communities in the 17th to 18th century. The focus of our research is one of the irrigation systems that used the water conveyed from the large water system. Not much is known about these small irrigation systems functioning in the Wadi Al Jizzi of the greater Sohar region. There are no written records and we can only make guesses about the way the systems were managed based on ethnographical studies and the traditional Omani techniques. On the other hand, the good preservation state of the canals offers a great opportunity for hydraulic reconstruction of irrigation events. More than that, the material remains suggest and at the same time limit the ways in which humans interacted with the system and the water resources of the region. All irrigation activities and some daily activities had to be realized through the canal system and only if the canal system permits it these actions would have been feasible. We created a conceptual model of irrigation that includes the human agent and feedback mechanisms through hydraulics and then we simulated irrigation events using the Sobek software. Scenarios and sensibility analysis were used to address the unknown aspects of the system. Our research yielded insights about the way the farming community interacted with the larger water system, the levels of co-ordination and co-operation required for successful irrigation and the predisposition of conflict and power relations.

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

    OpenAIRE

    Dechmi, Farida; Burguete, Javier; Skhiri, Ahmed

    2012-01-01

    The Soil and Water Assessment Tool (SWAT) is a well established, distributed, eco-hydrologic model. However, using the study case of an agricultural intensive irrigated watershed, it was shown that all the model versions are not able to appropriately reproduce the total streamflow in such system when the irrigation source is outside the watershed. The objective of this study was to modify the SWAT2005 version for correctly simulating the main hydrological processes. Crop yield, total streamfl...

  11. Impact of the Invasion of Modern Irrigation Systems in the Oasis of Lahmar, South Western Algeria

    OpenAIRE

    Cherif Rezzoug; Boualem Emini; Saed Hamoudi

    2016-01-01

    For centuries, the oasis dwellers of the Algerian Sahara exploit the groundwater through the use of traditional techniques such as foggaras (traditional technique of irrigation in the Algerian southwest), and wells of chadouf (pendulum wells). In the oasis of Lahmar, in Southwest Algeria, the farmers use foggaras (known by the name of foggaras ain - foggaras of source) to irrigate their fields. Nowadays though, due to the indiscriminate use of modern systems (boreholes and pump...

  12. Impact of different irrigation systems on water quality in peri-urban areas of Gujarat, India

    OpenAIRE

    Vangani, Ruchi; Saxena, Deepak; Gerber, Nikolaus; Mavalankar, Dileep; von Braun, Joachim

    2016-01-01

    The ever-growing population of India, along with the increasing competition for water for productive uses in different sectors - especially irrigated agriculture and related local water systems and drainage - poses a challenge in an effort to improve water quality and sanitation. In rural and peri-urban settings, where agriculture is one of the main sources of livelihood, the type of water use in irrigated agriculture has complex interactions with drinking water and sanitation. In particular,...

  13. Interactive Online Real-time Groundwater Model for Irrigation Water Allocation in the Heihe Mid-reaches, China

    Science.gov (United States)

    Pedrazzini, G.; Kinzelbach, W.

    2016-12-01

    In the Heihe Basin and many other semi-arid regions in the world the ongoing introduction of smart meter IC-card systems on farmers' pumping wells will soon allow monitoring and control of abstractions with the goal of preventing further depletion of the resource. In this regard, a major interest of policy makers concerns the development of new and the improvement of existing legislation on pricing schemes and groundwater/surface water quotas. Predictive knowledge on the development of groundwater levels for different allocation schemes or climatic change scenarios is required to support decision-makers in this task. In the past groundwater models have been a static component of investigations and their results delivered in the form of reports. We set up and integrated a groundwater model into a user-friendly web-based environment, allowing direct and easy access to the novice user. Through operating sliders the user can select an irrigation district, change irrigation patterns such as partitioning of surface- and groundwater, size of irrigation area, irrigation efficiency, as well as a number of climate related parameters. Reactive handles allow to display the results in real-time. The implemented software is all license free. The tool is currently being introduced to irrigation district managers in the project area. Findings will be available after some practical experience to be expected in a given time. The accessibility via a web-interface is a novelty in the context of groundwater models. It allows delivering a product accessible from everywhere and from any device. The maintenance and if necessary updating of model or software can occur remotely. Feedback mechanisms between reality and prediction will be introduced and the model periodically updated through data assimilation as new data becomes available. This will render the model a dynamic tool steadily available and evolving over time.

  14. Impacts of climate change on water footprint of spring wheat production: the case of an irrigation district in China

    Energy Technology Data Exchange (ETDEWEB)

    Sun, S. K.; Wu, P. T.; Wang, Y. B.; Zhao, X. N.

    2012-07-01

    The potential impacts of climate change are expected to reshape the patterns of demand and supply of water for agriculture, therefore the assessment of the impacts of climate change on agricultural water consumption will be essential. The water footprint provides a new approach to the assessment of agricultural water consumption under climate change. This paper provides an analysis of the impacts of climate changes on the water footprint of spring wheat in Hetao Irrigation District, China during 1980-2009. Results indicate that: 1) crop evapotranspiration and irrigation water requirements of spring wheat presented a downtrend owing to the climate factors variation in the study period; 2) under the combined influence of increasing crop yield and decreasing crop evapotranspiration, the water footprint decreased during the study period, exhibiting a trend of 0.025 m3 kg{sup -}1 yr{sup -}1; 3) the total contribution rate of the climatic factors for the decline of water footprint of spring wheat during the study period was only -10.45%. These results suggest that the water footprint of a crop, to a large extent, is determined by agricultural management rather than by the regional agro-climate and its variation. Nevertheless, we should pay attention to the adaptation of effective strategies for minimizing the agricultural production risk caused by climate change. (Author) 49 refs.

  15. Impact of Future Climate Change on Regional Crop Water Requirement—A Case Study of Hetao Irrigation District, China

    Directory of Open Access Journals (Sweden)

    Tianwa Zhou

    2017-06-01

    Full Text Available Water shortage is a limiting factor for agricultural production in China, and climate change will affect agricultural water use. Studying the effects of climate change on crop irrigation requirement (CIR would help to tackle climate change, from both food security and sustainable water resource use perspectives. This paper applied SDSM (Statistical DownScaling Model to simulate future meteorological parameters in the Hetao irrigation district (HID in the time periods 2041–2070 and 2071–2099, and used the Penman–Monteith equation to calculate reference crop evapotranspiration (ET0, which was further used to calculate crop evapotranspiration (ETc and crop water requirement (CWR. CWR and predicted future precipitation were used to calculate CIR. The results show that the climate in the HID will become warmer and wetter; ET0 would would increase by 4% to 7%; ETc and CWR have the same trend as ET0, but different crops have different increase rates. CIR would increase because of the coefficient of the increase of CWR and the decrease of effective precipitation. Based on the current growing area, the CIR would increase by 198 × 106 to 242 × 106 m3 by the year 2041–2070, and by 342 × 106 to 456 × 106 m3 by the years 2071–2099 respectively. Future climate change will bring greater challenges to regional agricultural water use.

  16. Regional Water Balance Based on Remotely Sensed Evapotranspiration and Irrigation: An Assessment of the Haihe Plain, China

    Directory of Open Access Journals (Sweden)

    Yanmin Yang

    2014-03-01

    Full Text Available Optimal planning and management of the limited water resources for maximum productivity in agriculture requires quantifying the irrigation applied at a regional scale. However, most efforts involving remote sensing applications in assessing large-scale irrigation applied (IA have focused on supplying spatial variables for crop models or studying evapotranspiration (ET inversions, rather than directly building a remote sensing data-based model to estimate IA. In this study, based on remote sensing data, an IA estimation model together with an ET calculation model (ETWatch is set up to simulate the spatial distribution of IA in the Haihe Plain of northern China. We have verified this as an effective approach for the simulation of regional IA, being more reflective of regional characteristics and of higher resolution compared to single site-specific results. The results show that annual ET varies from 527 mm to 679 mm and IA varies from 166 mm to 289 mm, with average values of 602 mm and 225 mm, respectively, from 2002 to 2007. We confirm that the region along the Taihang Mountain in Hebei Plain has serious water resource sustainability problems, even while receiving water from the South-North Water Transfer (SNWT project. This is due to the region’s intensive agricultural production and declining groundwater tables. Water-saving technologies, including more timely and accurate geo-specific IA assessments, may help reduce this threat.

  17. Mapping Daily Evapotranspiration based on Spatiotemporal Fusion of ASTER and MODIS Images over Irrigated Agricultural Areas in the Heihe River Basin, Northwest China

    Science.gov (United States)

    Huang, C.; LI, Y.

    2017-12-01

    Continuous monitoring of daily evapotranspiration (ET) is crucial for allocating and managing water resources in irrigated agricultural areas in arid regions. In this study, continuous daily ET at a 90-m spatial resolution was estimated using the Surface Energy Balance System (SEBS) by fusing Moderate Resolution Imaging Spectroradiometer (MODIS) images with high temporal resolution and Advanced Space-borne Thermal Emission Reflectance Radiometer (ASTER) images with high spatial resolution. The spatiotemporal characteristics of these sensors were obtained using the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM). The performance of this approach was validated over a heterogeneous oasis-desert region covered by cropland, residential, woodland, water, Gobi desert, sandy desert, desert steppe, and wetland areas using in situ observations from automatic meteorological systems (AMS) and eddy covariance (EC) systems in the middle reaches of the Heihe River Basin in Northwest China. The error introduced during the data fusion process based on STARFM is within an acceptable range for predicted LST at a 90-m spatial resolution. The surface energy fluxes estimated using SEBS based on predicted remotely sensed data that combined the spatiotemporal characteristics of MODIS and ASTER agree well with the surface energy fluxes observed using EC systems for all land cover types, especially for vegetated area with MAP values range from 9% to 15%, which are less than the uncertainty (18%) of the observed in this study area. Time series of daily ET modelled from SEBS were compared to that modelled from PT-JPL (one of Satellite-based Priestley-Taylor ET model) and observations from EC systems. SEBS performed generally better than PT-JPL for vegetated area, especially irrigated cropland with bias, RMSE, and MAP values of 0.29 mm/d, 0.75 mm/d, 13% at maize site, -0.33 mm/d, 0.81 mm/d, and 14% at vegetable sites.

  18. Fruit yield and root system distribution of 'Tommy Atkins' mango under different irrigation regimes

    Directory of Open Access Journals (Sweden)

    Marcelo R. dos Santos

    2014-04-01

    Full Text Available This study aimed to evaluate the fruit yield and the distribution of 'Tommy Atkins' mango root system under different irrigation regimes in the semiarid region of Bahia. The experimental design was completely randomized with five treatments and three replicates: 1 - Irrigation supplying 100% of ETc in phases I, II and III; 2 - Regulated deficit irrigation (RDI supplying 50% of ETc in phase I (beginning of flowering to early fruit growth; 3 - RDI supplying 50% ETc in phase II (start of expansion until the beginning of physiological maturity; 4 - RDI supplying 50% ETc in phase III (physiological mature fruits; 5 - No irrigation during all three phases. The regulated deficit irrigation supplying 50% of the ETc during phase I and II provided larger root length density of 'Tommy Atkins' mango. Regardless of management strategy, the roots were developed in all evaluated soil volume and the highest density is concentrated from 0.50 to 1.50 m distance from the trunk and in 0.20 to 0.90 m depth in the soil, that suggests this region to be the best place for fertilizer application as well for soil water sensor placement. The application of RDI during fruit set does not influence either root distribution or production. Root system and crop production is significantly reduced under no irrigation conditions.

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

    Directory of Open Access Journals (Sweden)

    M. Khorramian

    2017-01-01

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

  20. Accelerator control systems in China

    International Nuclear Information System (INIS)

    Yao Chihyuan

    1992-01-01

    Three accelerator facilities were built in the past few years, the 2.8 GeV electron positron collider BEPC, the heavy ion SSC cyclotron accelerator HIRFL and the 800 MeV synchrotron radiation storage ring HESYRL. Aimed at different research areas, they represent a new generation of accelerator in China. This report describes the design philosophy, the structure, performance as well as future improvements of the control systems of the these facilities. (author)

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

    Science.gov (United States)

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

    2015-01-01

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

  2. Ruling by canal: Governance and system-level design characteristics of large scale irrigation infrastructure in India and Uzbekistan

    Directory of Open Access Journals (Sweden)

    Peter Mollinga

    2016-06-01

    Full Text Available This paper explores the relationship between governance regime and large-scale irrigation system design by investigating three cases: 1 protective irrigation design in post-independent South India; 2 canal irrigation system design in Khorezm Province, Uzbekistan, as implemented in the USSR period, and 3 canal design by the Madras Irrigation and Canal Company, as part of an experiment to do canal irrigation development in colonial India on commercial terms in the 1850s-1860s. The mutual shaping of irrigation infrastructure design characteristics on the one hand and management requirements and conditions on the other has been documented primarily at lower, within-system levels of the irrigation systems, notably at the level of division structures. Taking a 'social construction of technology' perspective, the paper analyses the relationship between technological structures and management and governance arrangements at irrigation system level. The paper finds qualitative differences in the infrastructural configuration of the three irrigation systems expressing and facilitating particular forms of governance and rule, differences that matter for management and use, and their effects and impacts.

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

    Science.gov (United States)

    Salazar, LeRoy; And Others

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

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

    Science.gov (United States)

    Dechmi, Farida; Burguete, Javier; Skhiri, Ahmed

    2012-11-01

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

  5. Formation of nitrosodimethylamine (NDMA) during chlorine disinfection of wastewater effluents prior to use in irrigation systems.

    Science.gov (United States)

    Pehlivanoglu-Mantas, Elif; Hawley, Elisabeth L; Deeb, Rula A; Sedlak, David L

    2006-01-01

    The probable human carcinogen nitrosodimethylamine (NDMA) is produced when wastewater effluent is disinfected with chlorine. In systems where wastewater effluent is used for landscape or crop irrigation, relatively high chlorine doses (i.e., up to 2,000,mg-min/L) are often used to ensure adequate disinfection and to minimize biofouling in the irrigation system. To assess the formation of NDMA in such systems, samples were collected from several locations in full-scale wastewater treatment systems and their associated irrigation systems. Up to 460 ng/L of NDMA was produced in full-scale systems in which chloramines were formed when wastewater effluent was disinfected with chlorine in the presence of ammonia. Less than 20 ng/L of NDMA was produced in systems that used free chlorine (i.e., HOCl/OCl(-)) for disinfection in the absence of ammonia. The production of NDMA in ammonia-containing systems was correlated with the concentration of NDMA precursors in the wastewater effluent and the overall dose of chlorine applied. Much of the NDMA formation occurred in chlorine contact basins or in storage basins where water that contained chloramines was held after disinfection. When landscape or crop irrigation is practiced with ammonia-containing wastewater effluent, NDMA production can be controlled by use of lower chlorine doses or by application of alternative disinfectants.

  6. On the waterfront : water distribution, technology and agrarian change in a South Indian canal irrigation system

    NARCIS (Netherlands)

    Mollinga, P.P.

    1998-01-01

    This book discusses water distribution in the Tungabhadra Left Bank Canal irrigation system in Raichur district, Karnataka, India. The system is located in interior South India, where rainfall is limited (approximately 600 mm annually) and extremely variable. The region suffered from failed

  7. KAJIAN ASET NIRWUJUD DALAM MANAJEMEN SISTEM IRIGASI Study on Intangible Assets in Irrigation System Management

    Directory of Open Access Journals (Sweden)

    Nugroho Tri Waskitho

    2012-05-01

    Full Text Available The research aimed at studying on intangible assets at irrigation system management. The research method consisted oftwo stages. The first stage was data collecting which was done by questionnaire and interview on management of Water Use Associations (WUA in Mejing irrigation system in Bantul, Sapon irrigation system in Kulon Progo, Yogyakarta, and Molek irrigation system in Malang, East Java. The second stage was data analysis which was done using ANFIS (Adaptive Neuro Fuzzy Inference System.The research result indicated that knowledge management falls into four main components: (i learning organization, (ii principle of organization, (iii policy and strategy of organization, and (iv information and communication technology which are integrated for controlling intangible assets in irrigation system. Intangible assets consisted of human capital, structural capital, and relation capital which are integrated for controlling performance of irrigation system. Knowledge management in Mejing and Sapon irrigation systems were in moderate-good condition (3.81 in1-5 scale and in Molek irrigation system was poor (2.37. Intangible assets in Mejing, Sapon, and Molek irrigation systems were in moderate-good condition (3.61. Effectiveness of performance in Sapon, Mejing, and Molek irrigation systems were very good (0.89-0.95 and were very potential to develop. Each irrigation system had different priorities ABSTRAK Tujuan penelitian ini adalah mengkaji kondisi aset nirwujud dalam manajemen sistem irigasi ditinjau dari manajemenpengetahuan. Metode penelitian terdiri dari dua tahap. Tahap pertama adalah pengumpulan data yang dilakukan dengan kuesioner dan wawancara dengan pengurus Perkumpulan Petani Pemakai Air (P3A di Daerah Irigasi (DI Mejing di kabupaten Bantul, dan DI Sapon di kabupaten Kulon Progo, propinsi Daerah Istimewa Yogyakarta, dan DI Molek di kabupaten Malang, Jawa Timur. Tahap kedua adalah analisa data yang dilakukan dengan ANFIS (Adaptive Neuro

  8. Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

    Directory of Open Access Journals (Sweden)

    Silvana Tarlera

    2016-02-01

    Full Text Available ABSTRACT Water management impacts both methane (CH4 and nitrous oxide (N2O emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30; and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI. AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha−1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05. No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05 while AWDI promoted yield reduction in one of the seasons ( p< 0.05. When rice yield and greenhouse gases (GHG emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP. Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers.

  9. Carbon and water fluxes and footprints in tropical agricultural systems under rainfed and irrigated conditions

    Science.gov (United States)

    Johnson, M. S.; Lathuilliere, M. J.; Morillas, L.; Dalmagro, H. J.; D'Acunha, B.; Kim, Y.; Suarez, A.; Couto, E. G.

    2017-12-01

    In this talk, we will summarize results obtained using three tropical agricultural water observatories in Guanacaste, Costa Rica and Mato Grosso, Brazil. These flux towers and associated sensors enable detailed assessments of carbon use and water use efficiencies for crops under rain-fed and irrigated conditions. In addition to directly assessing water consumption from crops via eddy covariance, determination of water footprints and water use efficiencies using sensors and integrating it with remotely sensed data make it possible to (i) evaluate and compare different irrigation systems used in the study regions (drip, pivot and flood irrigation), (ii) assess the effect of irrigation over the local water balance to identify vulnerabilities associated with intensive water extraction for irrigation, and (iii) study the effect of inter-annual water availability fluctuations on crop water use. We conclude by comparing volumetric water footprints for crops, their carbon footprints, and water and carbon use efficiencies of crops produced under business-as-usual and alternative soil and water management scenarios.

  10. Integral Management of Irrigation Water in Intensive Horticultural Systems of Almería

    Directory of Open Access Journals (Sweden)

    Pedro Garcia-Caparros

    2017-12-01

    Full Text Available The development of intensive horticulture in Almería, with a huge increase in greenhouse surface area, is related to three essential factors: climatic characteristics, groundwater use and mulching sandy soil. The purpose of the present paper is to draw a picture of the integral management of water irrigation in the intensive horticultural systems in the region, by identifying the most significant water resource contributions and alternative water resources. Results indicate that the use of groundwater for the irrigation of horticultural crops in the greenhouses presents a high degree of overexploitation of the aquifers, but due to the continuous search for alternative water resources, such as desalinated and reclaimed water, as well as in-depth knowledge of the integral management of water irrigation through automated fertigation and localized irrigation systems, the current status of the water resources could be sustainable. Moreover, being conscious of the pollution generated by agricultural leachates, the horticultural system of Almería is implementing complementary sustainable systems such as recirculation, cascade cropping systems and phytodepuration for the reuse of the leachate. Considering all these factors, it can be concluded that the intensive horticultural system is on the right path towards respecting the environment and being sustainable in terms of water use.

  11. Irrigation in endodontic treatment.

    Science.gov (United States)

    Basrani, Bettina

    2011-01-01

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

  12. Re-engineering closing watersheds: The negotiated expansion of a dam-based irrigation system in Bolivia

    NARCIS (Netherlands)

    Rocha Lopez, R.F.; Vincent, L.F.; Rap, E.R.

    2015-01-01

    The expansion of the Totora Khocha dam-based irrigation system in the Pucara watershed is a case of planned re-engineering of a closing watershed. This article shows how, when irrigation systems expand in space and across boundaries to capture new water, they also involve new claims by existing and

  13. IRRIGATION USING SOLAR PUMP

    OpenAIRE

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

    2017-01-01

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

  14. Simulated optimization of crop yield through irrigation system design and operation based on the spatial variability of soil hydrodynamic properties

    International Nuclear Information System (INIS)

    Gurovich, L.; Stern, J.; Ramos, R.

    1983-01-01

    Spatial autocorrelation and kriging techniques were applied to soil infiltrability data from a 20 hectare field, to separate homogeneous irrigation units. Border irrigation systems were designed for each unit and combinations of units by using DESIGN, a computer model based on soil infiltrability and hydraulics of surface water flow, which enables optimal irrigation systems to be designed. Water depths effectively infiltrated at different points along the irrigation run were determined, and the agronomic irrigation efficiency of the unit evaluated. A modification of Hanks' evapotranspiration model, PLANTGRO, was used to evaluate plant growth, relative crop yield and soil-water economy throughout the growing season, at several points along each irrigation unit. The effect of different irrigation designs on total field yield and total water used for irrigation was evaluated by integrating yield values corresponding to each point, volume and inflow time during each irrigation. For relevant data from winter wheat grown in the central area of Chile during 1981, simulation by an interactive and sequentially recurrent use of DESIGN and PLANTGRO models, was carried out. The results obtained indicate that, when a field is separated into homogeneous irrigation units on the basis of the spatial variability of soil infiltrability and the border irrigation systems are designed according to soil characteristics, both a significant yield increase and less water use can be obtained by comparison with other criteria of field zonification for irrigation management. The use of neutrometric determinations to assess soil-water content during the growing season, as a validation of the results obtained in this work, is discussed. (author)

  15. Impact of the Invasion of Modern Irrigation Systems in the Oasis of Lahmar, South Western Algeria

    Directory of Open Access Journals (Sweden)

    Cherif Rezzoug

    2016-06-01

    Full Text Available For centuries, the oasis dwellers of the Algerian Sahara exploit the groundwater through the use of traditional techniques such as foggaras (traditional technique of irrigation in the Algerian southwest, and wells of chadouf (pendulum wells. In the oasis of Lahmar, in Southwest Algeria, the farmers use foggaras (known by the name of foggaras ain - foggaras of source to irrigate their fields. Nowadays though, due to the indiscriminate use of modern systems (boreholes and pumps to procure water for irrigation and urban consumption, over-exploitation and drying off of water sources have been one the rise while traditional techniques are becoming day by day out of service and, what is more, palm groves have almost completely disappeared.

  16. Adubarroz: a brazilian experience for fertilization and liming recommendation of irrigated rice via computational system

    Directory of Open Access Journals (Sweden)

    Felipe de Campos Carmona

    Full Text Available ABSTRACT: Recommendations for fertilizing irrigated rice in southern Brazil have been constantly evolving over years. In this process, the influence of factors such as the development cycle of varieties and sowing period increased. Thus, computational tools that take these and others important aspects into account can potentiate the fertilization response of rice. This study describes the computer program "ADUBARROZ". The software provides recommendations of fertilizer rates and liming requirements of irrigated rice, based on information entered by the user. The system takes various factors that regulate the crop response to fertilization into account. A final report is established with the graphical representation of input management over time.

  17. On the Waterfront. Water Distribution, Technology and Agrarian Change in a South Indian Canal Irrigation System

    NARCIS (Netherlands)

    Mollinga, P.P.

    2003-01-01

    This book analyses the struggle over water in a large-scale irrigation system in Raichur District, Karnataka, South India. It looks at water control as a simultaneously technical, managerial and socio-political process. The triangle of accommodation of different categories of farmers (head-enders

  18. The Middle Eastern Regional Irrigation Management Information Systems project-update

    Science.gov (United States)

    The Middle Eastern Regional Irrigation Management Information Systems Project (MERIMIS) was formulated at a meeting of experts from the region in Jordan in 2003. Funded by the U.S. Department of State, it is a cooperative regional project bringing together participants from Israel, Jordan, Palestini...

  19. Grey water treatment in a series anaerobic – Aerobic system for irrigation

    NARCIS (Netherlands)

    Abu-Ghunmi, L.N.A.H.; Zeeman, G.; Fayyad, M.; Lier, van J.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

  20. The history of the construction of main state irrigation systems in the postwar period

    Directory of Open Access Journals (Sweden)

    A. N. Chepurda

    2017-03-01

    It was established that the construction of large public irrigation systems in Ukraine started in 1951 stated that hydro construction that unfolded in the south of Ukraine, opened prospects to final elimination of the impact of drought and dry winds, the prospects for an unprecedented economic prosperity of the area.

  1. A low cost microcontroller-based automated irrigation system for two ...

    African Journals Online (AJOL)

    Maintaining soil water level is a necessary and pre-requisite for optimum crops production. Water is the essential elements for proper growth of crops in its optimum level; however its excessiveness should be avoided. Since irrigation is a dominant consumer of water, there must be a system which regulates the level of water ...

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

    NARCIS (Netherlands)

    Hoogesteger van Dijk, J.D.

    2015-01-01

    This paper analyzes conflict and collaboration and their relation to normative structures based on a case study of the history and external interventions of the Píllaro North Canal Irrigation System in the Ecuadorian Highlands. It does so by using Ostrom’s framework for analyzing the sustainability

  3. [Soil sandy desertification and salinization and their interrelationships in Yanghuang irrigated area of Hongsipu, Ningxia of northwest China].

    Science.gov (United States)

    Yang, Xin-guo; Song, Nai-ping

    2011-09-01

    By the methods of controlled and typical sampling, this paper analyzed the texture, salinization characteristics, cation exchange capacity (CEC), and their correlations in the 0-40 cm soil profiles of corn land, medlar land, and non-utilized land in Yanghuang irrigated area of Hongsipu, Northwest China. Under controlled sampling, the salt content in the soil profiles was 0.69-1.30 g x kg(-1) (except in non-utilized land where the 0-10 cm soil salt content was up to 1.74 g x kg(-1)), with no obvious salinization. The sodium adsorption ratio and exchangeable sodium percentage in the 20-40 cm soil layer of medlar land were 12.18 and 14.1%, respectively, and the total content of clay and silt in the 0-40 cm soil profile of medlar land was up to 37.3% whereas that in the 0-20 cm soil layer of corn land was only 13.5%. In the 20-40 cm soil layer of corn land, the indices of sandy desertification and salinization had significant correlations under controlled sampling but no correlations under typical sampling, while the CEC and the sandy desertification and salinization indices had significant correlations under typical sampling. In different land use types in the study area, soil sandy desertification and salinization had complicated interrelationships, and CEC could be used as the indicator for the changes in soil environmental quality.

  4. Effect of Cold-Water Irrigation on Grain Quality Traits in japonica Rice Varieties from Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Guo-zhen ZHAO

    2009-09-01

    Full Text Available The response of grain quality traits to cold-water irrigation and its correlation with cold tolerance were studied in 11 japonica rice varieties from Yunnan Province, China. The results indicated that the response of grain quality traits to the cold-water stress varied with rice varieties and grain quality traits. Under the cold-water stress, grain width, chalky rice rate, whiteness, 1000-grain weight, brown rice rate, taste meter value, peak viscosity, trough viscosity, breakdown viscosity and final viscosity significantly decreased, whereas grain length-width ratio, head rice rate, alkali digestion value, protein content and setback viscosity markedly increased. However, the other traits such as grain length, amylose content, milled rice rate, peak viscosity time and pasting temperature were not significantly affected by the cold-water stress. Significant correlations were discovered between phenotypic acceptability and cold response indices of taste meter value, protein content, peak viscosity and breakdown viscosity. Therefore, it would be very important to improve the cold tolerance of Yunnan rice varieties in order to stabilize and improve their eating quality.

  5. Heavy Metal Contamination and Ecological Risk Assessment of Swine Manure Irrigated Vegetable Soils in Jiangxi Province, China.

    Science.gov (United States)

    Wang, Maolan; Liu, Ronghao; Lu, Xiuying; Zhu, Ziyi; Wang, Hailin; Jiang, Lei; Liu, Jingjing; Wu, Zhihua

    2018-05-01

    Heavy metal are often added to animal fodder and accumulate in the soils with swine manure. In this study, heavy metal (Cu, Pb, Cd, Zn, As and Cr) concentrations were determined in agricultural soils irrigated with swine manure in Jiangxi Province, China. Results showed that the average concentrations of Cu, Zn, As and Cr (32.8, 93.7, 21.3 and 75.8 mg/kg, respectively) were higher than the background values, while Pb and Cd (15.2 and 0.090 mg/kg, respectively) were lower than the background values. Contamination factors [Formula: see text] indicated that they were generally moderate for Cu, Zn, As and Cr and generally low for Pb and Cd. The contamination degree (C d ) was calculated to be 7.5-10.0 indicating a moderate degree of contamination. The geoaccumulation index (I geo ) indicated that the soils were unpolluted with Zn, Cd and Pb, while unpolluted to moderately pollute with Cr, Cu and As. The single ecological risk factor [Formula: see text] revealed that the six heavy metals all belonged to low ecological risk. The ecological risk indices suggested that all the sampling sites were at low risk level.

  6. Assessments and market design for the water market at Xiying Irrigation, Shiyang River Basin, Gansu Province, China

    Science.gov (United States)

    Xu, T.; Zhao, J.; Zheng, H.

    2016-12-01

    As one of the pilot water markets in China, the market in Xiying Irrigation was built in 2008. Based on the historical trading data, it can be concluded that the studied market is growing but facing quite a few challenges. To solve these challenges, the first step we have done is assessment on the market. Some comparable indices were introduced from network science by us. These indices straightforwardly show the status and major problems in the market. One main problem we have found from surveys and our assessment is that there are barriers between distant seller and buyer. This discovery incentives us to develop a new mechanism for matching sellers and buyers to reduce the loss on social welfare. By modelling the trading barriers between a buyer and a seller as an indicator -- tradable or nontradable, the authors propose a mixed-integer linear programming algorithm to optimize the social welfare. According to the theories on competitive equilibrium, the authors are able to extend the programming to compute a reasonable price profile for each pair of tradable seller and buyer. It can be proved that given the price profile, the optimal strategy for each seller or buyer is to follow the optimal assignment. This mechanism significantly reduces the social welfare loss. However, this study shows that removing the trading barriers can brings more social welfare increments.

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

    Science.gov (United States)

    Çapar, İsmail Davut; Aydinbelge, Hale Ari

    2014-01-01

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

  8. Limiting nutrient emission from a cut rose closed system by high-flux irrigation and low nutrient concentrations?

    NARCIS (Netherlands)

    Baas, R.; Berg, van der D.

    2004-01-01

    A two-year project was aimed at decreasing nutrient emission from closed nutrient systems by using high irrigation rates in order to allow lower EC levels in the presence of accumulated Na and Cl. Experimental variables were growing media, irrigation frequencies, EC and NaCl concentrations for cut

  9. Integrated water-crop-soil-management system for evaluating the quality of irrigation water

    International Nuclear Information System (INIS)

    Pla-Sentis, I.

    1983-01-01

    The authors make use of an independent balance of the salts and ions present in the water available for irrigation, based on the residence times in the soil solution that are allowed by solubility limits and drainage conditions, to develop an efficient system for evaluating the quality of such water which combines the factors: water, crop, soil and management. The system is based on the principle that such quality depends not only on the concentration and composition of the salts dissolved in the water, but also on existing possibilities and limitations in using and managing it in respect of the soil and crops, with allowance for the crop's tolerance of salinity, drainage conditions and hydrological properties of the soils, climate and current or potential practices for the management of the irrigation. If this system is used to quantify approximately the time behaviour of the concentration and composition of the salts in the soil solution, it is possible not only to predict the effects on soil, crops and drainage water, but also to evaluate the various combinations of irrigation water, soil, crops and management and to select the most suitable. It is also useful for fairly accurately diagnosing current problems of salinity and for identifying alternatives and possibilities for reclamation. Examples of its use for these purposes in Venezuela are presented with particular reference to the diagnosis of the present and future development of ''salino-sodic'' and ''sodic'' soils by means of low-salt irrigation water spread over agricultural soils with very poor drainage in a sub-humid or semi-arid tropical climate. The authors also describe the use of radiation techniques for gaining an understanding of the relations between the factors making up the system and for improving the quantitative evaluations required to diagnose problems and to select the best management methods for the available irrigation water. (author)

  10. Optimal Pipe Size Design for Looped Irrigation Water Supply System Using Harmony Search: Saemangeum Project Area

    Science.gov (United States)

    Lee, Ho Min; Sadollah, Ali

    2015-01-01

    Water supply systems are mainly classified into branched and looped network systems. The main difference between these two systems is that, in a branched network system, the flow within each pipe is a known value, whereas in a looped network system, the flow in each pipe is considered an unknown value. Therefore, an analysis of a looped network system is a more complex task. This study aims to develop a technique for estimating the optimal pipe diameter for a looped agricultural irrigation water supply system using a harmony search algorithm, which is an optimization technique. This study mainly serves two purposes. The first is to develop an algorithm and a program for estimating a cost-effective pipe diameter for agricultural irrigation water supply systems using optimization techniques. The second is to validate the developed program by applying the proposed optimized cost-effective pipe diameter to an actual study region (Saemangeum project area, zone 6). The results suggest that the optimal design program, which applies an optimization theory and enhances user convenience, can be effectively applied for the real systems of a looped agricultural irrigation water supply. PMID:25874252

  11. Optimal Pipe Size Design for Looped Irrigation Water Supply System Using Harmony Search: Saemangeum Project Area

    Directory of Open Access Journals (Sweden)

    Do Guen Yoo

    2015-01-01

    Full Text Available Water supply systems are mainly classified into branched and looped network systems. The main difference between these two systems is that, in a branched network system, the flow within each pipe is a known value, whereas in a looped network system, the flow in each pipe is considered an unknown value. Therefore, an analysis of a looped network system is a more complex task. This study aims to develop a technique for estimating the optimal pipe diameter for a looped agricultural irrigation water supply system using a harmony search algorithm, which is an optimization technique. This study mainly serves two purposes. The first is to develop an algorithm and a program for estimating a cost-effective pipe diameter for agricultural irrigation water supply systems using optimization techniques. The second is to validate the developed program by applying the proposed optimized cost-effective pipe diameter to an actual study region (Saemangeum project area, zone 6. The results suggest that the optimal design program, which applies an optimization theory and enhances user convenience, can be effectively applied for the real systems of a looped agricultural irrigation water supply.

  12. Risk Assessment and Prediction of Heavy Metal Pollution in Groundwater and River Sediment: A Case Study of a Typical Agricultural Irrigation Area in Northeast China

    Directory of Open Access Journals (Sweden)

    Shuang Zhong

    2015-01-01

    Full Text Available The areas with typical municipal sewage discharge river and irrigation water function were selected as study sites in northeast China. The samples from groundwater and river sediment in this area were collected for the concentrations and forms of heavy metals (Cr(VI, Cd, As, and Pb analysis. The risk assessment of heavy metal pollution was conducted based on single-factor pollution index (I and Nemerow pollution index (NI. The results showed that only one groundwater sampling site reached a polluted level of heavy metals. There was a high potential ecological risk of Cd on the N21-2 sampling site in river sediment. The morphological analysis results of heavy metals in sediment showed that the release of heavy metals can be inferred as one of the main pollution sources of groundwater. In addition, the changes in the concentration and migration scope of As were predicted by using the Groundwater Modeling System (GMS. The predicted results showed that As will migrate downstream in the next decade, and the changing trend of As polluted areas was changed with As content districts because of some pump wells downstream to form groundwater depression cone, which made the solute transfer upstream.

  13. Risk Assessment and Prediction of Heavy Metal Pollution in Groundwater and River Sediment: A Case Study of a Typical Agricultural Irrigation Area in Northeast China

    Science.gov (United States)

    Zhong, Shuang; Geng, Hui; Zhang, Fengjun; Liu, Zhaoying; Wang, Tianye; Song, Boyu

    2015-01-01

    The areas with typical municipal sewage discharge river and irrigation water function were selected as study sites in northeast China. The samples from groundwater and river sediment in this area were collected for the concentrations and forms of heavy metals (Cr(VI), Cd, As, and Pb) analysis. The risk assessment of heavy metal pollution was conducted based on single-factor pollution index (I) and Nemerow pollution index (NI). The results showed that only one groundwater sampling site reached a polluted level of heavy metals. There was a high potential ecological risk of Cd on the N21-2 sampling site in river sediment. The morphological analysis results of heavy metals in sediment showed that the release of heavy metals can be inferred as one of the main pollution sources of groundwater. In addition, the changes in the concentration and migration scope of As were predicted by using the Groundwater Modeling System (GMS). The predicted results showed that As will migrate downstream in the next decade, and the changing trend of As polluted areas was changed with As content districts because of some pump wells downstream to form groundwater depression cone, which made the solute transfer upstream. PMID:26366176

  14. Reclaimed water as a reservoir of antibiotic resistance genes: distribution system and irrigation implications

    Directory of Open Access Journals (Sweden)

    Nicole L Fahrenfeld

    2013-05-01

    Full Text Available 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. 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 point of use, and that attention should be directed towards the fate of ARGs in irrigation water and the implications for human health.

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

    NARCIS (Netherlands)

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

    2014-01-01

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

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

    Science.gov (United States)

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

    2011-12-01

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

  17. Wastewater retreatment and reuse system for agricultural irrigation in rural villages.

    Science.gov (United States)

    Kim, Minyoung; Lee, Hyejin; Kim, Minkyeong; Kang, Donghyeon; Kim, Dongeok; Kim, YoungJin; Lee, Sangbong

    2014-01-01

    Climate changes and continuous population growth increase water demands that will not be met by traditional water resources, like surface and ground water. To handle increased water demand, treated municipal wastewater is offered to farmers for agricultural irrigation. This study aimed to enhance the effluent quality from worn-out sewage treatment facilities in rural villages, retreat effluent to meet water quality criteria for irrigation, and assess any health-related and environmental impacts from using retreated wastewater irrigation on crops and in soil. We developed the compact wastewater retreatment and reuse system (WRRS), equipped with filters, ultraviolet light, and bubble elements. A pilot greenhouse experiment was conducted to evaluate lettuce growth patterns and quantify the heavy metal concentration and pathogenic microorganisms on lettuce and in soil after irrigating with tap water, treated wastewater, and WRRS retreated wastewater. The purification performance of each WRRS component was also assessed. The study findings revealed that existing worn-out sewage treatment facilities in rural villages could meet the water quality criteria for treated effluent and also reuse retreated wastewater for crop growth and other miscellaneous agricultural purposes.

  18. [Responses of antioxidation system of Cynodon dactylon to recirculated landfill leachate irrigation].

    Science.gov (United States)

    Wang, Ruyi; He, Pinjing; Shao, Liming; Zhang, Bin; Li, Guojian

    2005-05-01

    With pot experiment, this paper studied the membrane lipid peroxidation and the variations of antioxidation system in Cynodon dactylon under recirculated landfill leachate irrigation. The results showed that when irrigated with low dilution ratio ( 25%), there existed an obvious negative fect on Cynodon dactylon, i.e., the chlorophyll a/b ratio decreased, while cell membrane permeability and MDA and H2O2 contents increased, which meant that the membrane lipid peroxidation was accelerated. The contents antioxidants AsA, GSH and Car also showed the similar trend, i.e., they increased with increasing leachate dilution ratio when irrigated with low dilution ratio leachate, but decreased under medium or high dilution ratio leachate irrigation. Among three test anti-oxidative enzymes, SOD and POD activities showed a similar change test antioxidants, and POD activity was more sensitive, while CAT activity was on the contrary. The contents test antioxidants and the activities of SOD and POD were negatively and significantly correlated to MDA content, indicating that they might play an important role in preventing Cynodon dactylon from cell membrane lipid peroxdation.

  19. Monitoring of the humus status of soils of the Ingulets irrigation system

    Science.gov (United States)

    Lozovitsii, P. S.

    2012-03-01

    The results of long-term studies (1957-2007) of the changes in the morphology of soil profiles and in the reserves and fractional composition of the humus in the soils of the Ingulets irrigation system are discussed. After 50 years of irrigation, the boundaries of the genetic horizons shifted downward by 15-30 cm. The redistribution of the humus took place: its content decreased to a low level in the plow layer of the irrigated and rainfed soils and significantly increased in the layer of 60-100 cm so that the reserves of humus in the layer of 0-100 cm somewhat increased and corresponded to a moderate level. The distribution of humus in the soil profiles was characterized by the gradual lowering down the soil profile. The concentration of nitrogen in the humus of the irrigated southern chernozems was very low. The degree of humification of the soil organic matter was high. The humus was of the humate type in the upper horizons and of the fulvate-humate type in the lower horizons.

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

    International Nuclear Information System (INIS)

    Vabre, Alexandre

    2000-01-01

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

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

    Science.gov (United States)

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

    2017-11-01

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

  2. The impacts of climate change on irrigation and crop production in Northeast China and implications for energy use and GHG Emission

    Science.gov (United States)

    Yan, Tingting; Wang, Jinxia; Huang, Jikun; Xie, Wei; Zhu, Tingju

    2018-06-01

    The water-food-energy-GHG nexus under climate change has been gaining increasing attention from both the research and policy communities, especially over the past several years. However, most existing nexus studies are qualitative and explorative in nature. So far, very few studies provide integrated analysis of this nexus across all the four sectors. The purpose of this paper is to examine this nexus by assessing the effects of climate change on agricultural production through the change in water availability, evaluating the adjustment responses and resulting energy consumption and GHG emission, with the Northeast China as a case study. Based on our simulation results, by 2030, climate change is projected to increase water supply and demand gap for irrigation in Northeast China. Due to the increase in water scarcity, irrigated areas will decrease, and the cropping pattern will be adjusted by increasing maize sown areas and decreasing rice sown areas. As a result, the total output of crops and profits will clearly be reduced. Finally, energy consumption and GHG emission from irrigation will be reduced. This study suggests that climate change impact assessment fully consider the nexus among water, food, energy and GHG; however, more studies need to be conducted in the future.

  3. Study Of Solar PV Sizing Of Water Pumping System For Irrigation Of Asparagus

    Directory of Open Access Journals (Sweden)

    Mya Su Kyi

    2015-08-01

    Full Text Available The motivation for this system come from the countries where economy is depended on agriculture and the climatic conditions lead to lack of rains. The farmers working in the farm lands are dependent on the rains and bore wells. Even if the farm land has a water-pump manual involvement by farmers is required to turn the pump onoff when on earth needed. This paper presents design and calculation analysis of efficient Solar PV water pumping system for irrigation of Asparagus. The study area falls 21-58-30 N Latitude and 96-5-0 E Longitude of Mandalay. The PV system sizing was made in such a way that it was capable of irrigation one acre of Asparagus plot with a daily water requirement of 25mday.

  4. Natural and anthropogenic factors affecting the shallow groundwater quality in a typical irrigation area with reclaimed water, North China Plain.

    Science.gov (United States)

    Gu, Xiaomin; Xiao, Yong; Yin, Shiyang; Pan, Xingyao; Niu, Yong; Shao, Jingli; Cui, Yali; Zhang, Qiulan; Hao, Qichen

    2017-09-22

    In this study, the hydrochemical characteristics of shallow groundwater were analyzed to get insight into the factors affecting groundwater quality in a typical agricultural dominated area of the North China Plain. Forty-four shallow groundwater samples were collected for chemical analysis. The water type changes from Ca·Na-HCO 3 type in grass land to Ca·Na-Cl (+NO 3 ) type and Na (Ca)-Cl (+NO 3 +SO 4 ) type in construction and facility agricultural land, indicating the influence of human activities. The factor analysis and geostatistical analysis revealed that the two major factors contributing to the groundwater hydrochemical compositions were the water-rock interaction and contamination from sewage discharge and agricultural fertilizers. The major ions (F, HCO 3 ) and trace element (As) in the shallow groundwater represented the natural origin, while the nitrate and sulfate concentrations were related to the application of fertilizer and sewage discharge in the facility agricultural area, which was mainly affected by the human activities. The values of pH, total dissolved solids, electric conductivity, and conventional component (K, Ca, Na, Mg, Cl) in shallow groundwater increased from grass land and cultivated land, to construction land and to facility agriculture which were originated from the combination sources of natural processes (e.g., water-rock interaction) and human activities (e.g., domestic effluents). The study indicated that both natural processes and human activities had influences on the groundwater hydrochemical compositions in shallow groundwater, while anthropogenic processes had more contribution, especially in the reclaimed water irrigation area.

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

    Science.gov (United States)

    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

  6. FOOD SAFETY CONTROL SYSTEM IN CHINA

    Institute of Scientific and Technical Information of China (English)

    Liu Wei-jun; Wei Yi-min; Han Jun; Luo Dan; Pan Jia-rong

    2007-01-01

    Most countries have expended much effort to develop food safety control systems to ensure safe food supplies within their borders. China, as one of the world's largest food producers and consumers,pays a lot of attention to food safety issues. In recent years, China has taken actions and implemented a series of plans in respect to food safety. Food safety control systems including regulatory, supervisory,and science and technology systems, have begun to be established in China. Using, as a base, an analysis of the current Chinese food safety control system as measured against international standards, this paper discusses the need for China to standardize its food safety control system. We then suggest some policies and measures to improve the Chinese food safety control system.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  8. Sustainable automotive energy system in China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiliang (ed.) [Tsinghua Univ. Beijing (China). China Automotive Energy Research Center

    2013-06-01

    The latest research available on automotive energy system analysis in China. Thorough introduction on automotive energy system in China. Provides the broad perspective to aid in planning sustainable road transport in China. Sustainable Automotive Energy System in China aims at identifying and addressing the key issues of automotive energy in China in a systematic way, covering demography, economics, technology and policy, based on systematic and in-depth, multidisciplinary and comprehensive studies. Five scenarios of China's automotive energy development are created to analyze the possible contributions in the fields of automotive energy, vehicle fuel economy improvement, electric vehicles, fuel cell vehicles and the 2nd generation biofuel development. Thanks to this book, readers can gain a better understanding of the nature of China's automotive energy development and be informed about: (1) the current status of automotive energy consumption, vehicle technology development, automotive energy technology development and policy; (2) the future of automotive energy development, fuel consumption, propulsion technology penetration and automotive energy technology development, and (3) the pathways of sustainable automotive energy transformation in China, in particular, the technological and the policy-related options. This book is intended for researchers, engineers and graduates students in the low-carbon transportation and environmental protection field.

  9. Grey water treatment in a series anaerobic--aerobic system for irrigation.

    Science.gov (United States)

    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%, respectively. Sludge in the anaerobic and aerobic reactor has a concentration of 168 and 8 mg VSL(-1), respectively. Stability of sludge in the anaerobic and aerobic reactors is 80% and 93%, respectively, based on COD. Aerobic effluent quality, except for pathogens, agrees with the proposed irrigation water quality guidelines for reclaimed water in Jordan.

  10. Culinary and pressure irrigation water system hydroelectric generation

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, Cory [Water Works Engineers, Pleasant Grove City, UT (United States)

    2016-01-29

    Pleasant Grove City owns and operates a drinking water system that included pressure reducing stations (PRVs) in various locations and flow conditions. Several of these station are suitable for power generation. The City evaluated their system to identify opportunities for power generation that can be implemented based on the analysis of costs and prediction of power generation and associated revenue. The evaluation led to the selection of the Battle Creek site for development of a hydro-electric power generating system. The Battle Creek site includes a pipeline that carries spring water to storage tanks. The system utilizes a PRV to reduce pressure before the water is introduced into the tanks. The evaluation recommended that the PRV at this location be replaced with a turbine for the generation of electricity. The system will be connected to the utility power grid for use in the community. A pelton turbine was selected for the site, and a turbine building and piping system were constructed to complete a fully functional power generation system. It is anticipated that the system will generate approximately 440,000 kW-hr per year resulting in $40,000 of annual revenue.

  11. Integral Management of Irrigation Water in Intensive Horticultural Systems of Almería

    OpenAIRE

    Pedro Garcia-Caparros; Juana Isabel Contreras; Rafael Baeza; Maria Luz Segura; Maria Teresa Lao

    2017-01-01

    The development of intensive horticulture in Almería, with a huge increase in greenhouse surface area, is related to three essential factors: climatic characteristics, groundwater use and mulching sandy soil. The purpose of the present paper is to draw a picture of the integral management of water irrigation in the intensive horticultural systems in the region, by identifying the most significant water resource contributions and alternative water resources. Results indicate that the use of gr...

  12. Smart Water Conservation System for Irrigated Landscape. ESTCP Cost and Performance Report

    Science.gov (United States)

    2016-10-01

    irrigation practices (timer based and manual watering systems) that are no longer sustainable given the limited water supplies in many U.S. locations and...Areas that have high local water costs or limited water supply options may also benefit from water harvesting. The implementation of smart ET...in potable water use. Smart ET controllers with centralized and site-specific sensor inputs, such as ET gauge, rain, soil moisture, and leak

  13. Irrigation, Planting Date And Intra-Row Spacing Effects On Soybean Grown Under Dry Farming Systems

    OpenAIRE

    Ismail, A. M. A. [احمد محمد علي اسماعيل; Khalifa, F. M.

    1987-01-01

    Two soybean cultivars (Glycine maxima (L) Merr.) differing in maturity period, leaf size and stem height were sown five times at fortnight intervals during the rainy season at four intra—row spacings under supplementary irrigation at one site and under rainfed conditions at another site in the central rainlands of Sudan. Cultivars responded differently to the system of production. Sowing date and moisture availability were the main factors controlling soybean production. The late maturing cul...

  14. Deficit irrigation and fertilization strategies to improve soil quality and alfalfa yield in arid and semi-arid areas of northern China.

    Science.gov (United States)

    Jia, Qianmin; Kamran, Muhammad; Ali, Shahzad; Sun, Lefeng; Zhang, Peng; Ren, Xiaolong; Jia, Zhikuan

    2018-01-01

    In the arid and semi-arid areas of northern China, overexploitation of fertilizers and extensive irrigation with brackish groundwater have led to soil degradation and large areas of farmland have been abandoned. In order to improve the soil quality of abandoned farmland and make reasonable use of brackish groundwater, we conducted field trials in 2013 and 2014. In our study, we used three fertilization modes (CF, chemical fertilizer; OM, organic manure and chemical fertilizer; NF, no fertilizer) and three deficit irrigation levels (I 0 : 0 mm; I 75 : 75 mm; I 150 : 150 mm). The results showed that the activities of soil urease, alkaline phosphatase, invertase, catalase, and dehydrogenase in the OM treatment were significantly improved compared with those in the CF and NF treatments under the three deficit irrigation levels. Compared with NF, the OM treatment significantly increased soil organic carbon (SOC), water-soluble carbon (WSC), total nitrogen, microbial biomass carbon and nitrogen (MBC and MBN), and soil respiration rate, and significantly decreased soil C:N and MBC:MBN ratios and the metabolic quotient, thus improving the soil quality of abandoned farmland. Furthermore, the OM treatment increased alfalfa plant height, leaf area index, leaf chlorophyll content, and biomass yield. Under the CF and OM fertilization modes, the activities of urease and catalase in I 150 were significantly higher than those in I 0 , whereas irrigating without fertilizer did not significantly increase the activity of these two enzymes. Regardless of fertilization, alkaline phosphatase activity increased with an increase in irrigation amount, whereas invertase activity decreased. The results showed that deficit irrigation with brackish groundwater under the OM treatment can improve soil quality. Over the two years of the study, maximum SOC, total nitrogen, WSC, MBC, and MBN were observed under the OM-I 150 treatment, and the alfalfa biomass yield of this treatment was also

  15. Deficit irrigation and fertilization strategies to improve soil quality and alfalfa yield in arid and semi-arid areas of northern China

    Directory of Open Access Journals (Sweden)

    Qianmin Jia

    2018-02-01

    Full Text Available Background In the arid and semi-arid areas of northern China, overexploitation of fertilizers and extensive irrigation with brackish groundwater have led to soil degradation and large areas of farmland have been abandoned. In order to improve the soil quality of abandoned farmland and make reasonable use of brackish groundwater, we conducted field trials in 2013 and 2014. Methods In our study, we used three fertilization modes (CF, chemical fertilizer; OM, organic manure and chemical fertilizer; NF, no fertilizer and three deficit irrigation levels (I0: 0 mm; I75: 75 mm; I150: 150 mm. Results The results showed that the activities of soil urease, alkaline phosphatase, invertase, catalase, and dehydrogenase in the OM treatment were significantly improved compared with those in the CF and NF treatments under the three deficit irrigation levels. Compared with NF, the OM treatment significantly increased soil organic carbon (SOC, water-soluble carbon (WSC, total nitrogen, microbial biomass carbon and nitrogen (MBC and MBN, and soil respiration rate, and significantly decreased soil C:N and MBC:MBN ratios and the metabolic quotient, thus improving the soil quality of abandoned farmland. Furthermore, the OM treatment increased alfalfa plant height, leaf area index, leaf chlorophyll content, and biomass yield. Under the CF and OM fertilization modes, the activities of urease and catalase in I150 were significantly higher than those in I0, whereas irrigating without fertilizer did not significantly increase the activity of these two enzymes. Regardless of fertilization, alkaline phosphatase activity increased with an increase in irrigation amount, whereas invertase activity decreased. Discussion The results showed that deficit irrigation with brackish groundwater under the OM treatment can improve soil quality. Over the two years of the study, maximum SOC, total nitrogen, WSC, MBC, and MBN were observed under the OM-I150 treatment, and the alfalfa

  16. SCADA system with predictive controller applied to irrigation canals

    OpenAIRE

    Figueiredo, João; Botto, Miguel; Rijo, Manuel

    2013-01-01

    This paper applies a model predictive controller (MPC) to an automatic water canal with sensors and actuators controlled by a network (programmable logic controller), and supervised by a SCADA system (supervisory control and a data acquisition). This canal is composed by a set of distributed sub-systems that control the water level in each canal pool, constrained by discharge gates (control variables) and water off-takes (disturbances). All local controllers are available through an industria...

  17. Potential of renewable energy systems in China

    DEFF Research Database (Denmark)

    Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad

    2011-01-01

    Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO2 emitting country in the world. In this case...... system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy...... system. The conclusion is that China’s domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system...

  18. Hydraulic performance evaluation of pressure compensating (pc) emitters and micro-tubing for drip irrigation system

    International Nuclear Information System (INIS)

    Mangrio, A.G.; Asif, M.; Jahangir, I.

    2013-01-01

    Drip irrigation system is necessary for those areas, where the water scarcity issues are present. The present study was conducted at the field station of Climate Change, Alternate Energy and Water Resources Institute (CAEWRI), National Agricultural Research Center (NARC), Islamabad, during 2013, regarding drip irrigation system. Drip irrigation system depends on uniform emitter application flow. All the emitters were tested and replicated thrice at pressure head (34 to 207Kpa) with an increment of 34 Kpa. The minimum and maximum discharges were 1.32 - 3.52, 3.36 - 5.42, and 43.22 - 100.99 Lph, with an average of 2.42, 4.63 and 73.66 Lph, for Bow Smith, RIS and Micro-tubing, respectively. It indicates that more than 90% of emission uniformity (EU) and uniformity coefficient (CU) for all Emitters, which shows excellent water application with least standard deviation, ranging 0.12 to 2.37, throughout the operating pressure heads in all emitters. An average coefficient of variation (CV) of all emitters were behaving less than 0.07, indicating an excellent class at all operating pressure heads between 34 to 207 Kpa. Moreover, the relationship of discharge and pressure of emitters indicates that discharge increased with the increase of pressure head. The Q-H curve plays key role in the selection of emitters. (author)

  19. A Solar Energy Powered Autonomous Wireless Actuator Node for Irrigation Systems

    OpenAIRE

    Lajara, Rafael; Alberola, Jorge; Pelegr?-Sebasti?, Jos?

    2010-01-01

    The design of a fully autonomous and wireless actuator node ("wEcoValve mote") based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered...

  20. Irrigation water management: Basic principles and applications

    OpenAIRE

    Ella, Victor B.

    2007-01-01

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

  1. A Wireless Low Power Valve Controller for Drip Irrigation Control Systems

    Directory of Open Access Journals (Sweden)

    Haijiang Tai

    2014-03-01

    Full Text Available Drip irrigation control systems in fields generally include a large number of sensors and valves; controlling these devices efficiently can be achieved by using distributed irrigation control (DIC, which has the advantages of reduced wiring and piping costs and easier installation and maintenance. In this study, a wireless low power valve controller for drip irrigation control systems was developed and tested. The specific tasks included the controller design (hardware and software, energy consumption tests, and field tests. The controller uses the highly integrated JN5139 module, which is based on IEEE802.15.4, for hardware design; low power consumption sleep algorithms for software design; and two alkaline batteries for supply of power to the valve controller. Results of laboratory and field tests show continuous working days of the valve controller powered by two alkaline batteries are at least 3 months under different sleep periods and frequencies of valve control. The controller described here is characterized as reliable, low cost, easy to install, and having low power consumption.

  2. FEATURES OF MINERAL NUTRITION FOR TOMATO PLANTS WITH DRIP IRRIGATION SYSTEM IN OPEN FIELD CONDITION

    Directory of Open Access Journals (Sweden)

    P. M. Akhmetova

    2017-01-01

    Full Text Available Dagestan is the largest region with irrigation system of agriculture in Russia. Irrigated lands provide 70% of total plant production. The field cultivation is carried on arable land in plain region of the republic. The drip irrigation as an ecologically safe technology for watering is regarded as major means for vegetable production farming. This approach maintains the propitious level of water and air in the soil without surface and deep drainage of irrigating water. These irrigated lands are expected to be used first of all for valuable and profitable crops such as tomato that is a leading crop in Dagestan. The experimental work was carried out at OOO ‘Dagagrocomplex’, Aleksandro-Nevskoye, in Tarumovskiy region. The aim of the study was to determinate the optimal dose of mineral fertilizers and the way of their application to improve the productivity without quality loss. The complex analysis of the technology for tomato production under drip irrigation through nontransplanting culture showed its high efficiency, because volume and quality of yield directly depended on soil moisture and precise supporting of mineral nutrition rates. The maximal yield of tomato fruits, 88.7-94.5 t/ha was observed with once mineral fertilizer application at a dose of N180P135K60 with soil humidity 70-80% (field moisture capacity, and also at the dose of N180P135K60 with basic application of N100 in nutrition rate. The result of the study showed that the optimization of two factors, namely soil water rate and mineral nutrition, enabled to produce additionally 39.2 t/ha. It was shown the tight connection between yielding and its quality; when yielding 95 t/ha, the increased contents of dry matter to 7.01%, sugar to 3.8% vitamin C to 18.46% were noticed. The high quality of produced output was supported by pre-watering threshold of moisture at 75-80% (field moisture capacity, when once fertilizer application at a dose of N180P135K60. 

  3. Potential of renewable energy systems in China

    International Nuclear Information System (INIS)

    Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad; Zhang, Xiliang

    2011-01-01

    Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO 2 emitting country in the world. In this case, the inappropriate energy consumption structure should be changed. As an alternative, a suitable infrastructure for the implementation of renewable energy may serve as a long-term sustainable solution. The perspective of a 100% renewable energy system has been analyzed and discussed in some countries previously. In this process, assessment of domestic renewable energy sources is the first step. Then appropriate methodologies are needed to perform energy system analyses involving the integration of more sustainable strategies. Denmark may serve as an example of how sustainable strategies can be implemented. The Danish system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy system. The conclusion is that China's domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system in China is not unreasonable. (author)

  4. Design and Management of Irrigation Systems Diseño y Manejo de Sistemas de Riego

    Directory of Open Access Journals (Sweden)

    Eduardo A Holzapfel

    2009-12-01

    Full Text Available Irrigation systems should be a relevant agent to give solutions to the increasing demand of food, and to the development, sustainability and productivity of the agricultural sector. The design, managing, and operation of irrigation systems are crucial factors to achieve an efficient use of the water resources and the success in the production of crops and orchards. The aim of this paper is to analyze knowledge and investigations that enable to identify the principal criteria and processes that allow improving the design and managing of the irrigation systems, based on the basic concept that they facilitate to develop agriculture more efficient and sustainable. The design and managing of irrigation systems must have its base in criteria that are relevant, which implies to take into account agronomic, soil, hydraulic, economic, energetic, and environmental factors. The optimal design and managing of irrigation systems at farm level is a factor of the first importance for a rational use of water, economic development of the agriculture and its environmental sustainability.Los sistemas de riego deberían ser un agente relevante para dar soluciones a la demanda creciente de alimentos, y el desarrollo, sustentabilidad y productividad del sector agrícola. El diseño, manejo, y operación de los sistemas de riego son factores cruciales para lograr un uso eficiente de los recursos hídricos y el éxito en la producción de cultivos y frutales. El objetivo de este artículo fue analizar conocimientos e investigaciones que permitan identificar los principales criterios y procesos para mejorar el diseño y manejo de los sistemas de riego, basados en el concepto básico de desarrollar una agricultura más eficiente y sostenible. El diseño y manejo de los sistemas de riego deben tener su base en criterios que sean relevantes, lo que implica considerar aspectos agronómicos, de suelo, hidráulicos, económicos, energéticos, y ambientales. El diseño y

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

    Directory of Open Access Journals (Sweden)

    Gurudutt Nayak

    2014-06-01

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

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

    Science.gov (United States)

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

    2014-05-01

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

  7. Distribution Of 15N Fertilizer Added To Sandy Soil Under Drip Irrigation System As Affected By Irrigation Frequencies

    International Nuclear Information System (INIS)

    GADALLA, A.M.; GALAL, Y.G.M.; EL-GENDY, R.W.; ISMAIL, M.M.; EL-DEGWY, S.M.; KASSAB, M.F.

    2009-01-01

    Neutron moisture meter and stable nitrogen isotope ( 15 N) were used to follow horizontal and vertical water movement and N-fertilizer added to soil before and after irrigation. The data indicated that soil moisture distribution and values of total hydraulic potential depend on soil moisture content. Characterization of nitrogen in soil for all sites around the emitter indicated spatial variability with different soil depths due to leaching and volatilization processes. Moreover, water movement and flow direction greatly were characterized by active evaporation depth which was 30 cm.

  8. Set Up of an Automatic Water Quality Sampling System in Irrigation Agriculture

    Directory of Open Access Journals (Sweden)

    Emanuel Heinz

    2013-12-01

    Full Text Available We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS for stable water isotope analysis (δ2H and δ18O, a reagentless hyperspectral UV photometer (ProPS for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system’s technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season.

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

    Directory of Open Access Journals (Sweden)

    Chasseriaux G.

    2006-01-01

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

  10. A California Statewide App to Simulate Fate of Nitrate in Irrigated Agricultural System

    Science.gov (United States)

    Diamantopoulos, E.; Walkinshaw, M.; Harter, T.; O'Geen, A. T.

    2017-12-01

    Groundwater resources are very important for California's economic development and environmental sustainability. Nitrate is by far the most widespread anthropogenic groundwater pollutant in California's mostly alluvial groundwater basins. Major sources are synthetic fertilizer and dairy manure, but also septic systems and urban wastewater effluent. Here, we evaluate agricultural soils in California according to their risk for nitrate leaching. We conducted over 1 million numerical simulations taking into account the effect of climate, crop type, irrigation and fertilization management scenarios across all 4,568 agricultural soil profiles occurring in California. The assessment was done solving 1-D Richards equation and the advection-dispersion equation numerically. This study is focused on the complex water and nitrate dynamics occurring at the shallow vadose zone (rootzone). The results of this study allow the construction of state-wide maps which can be used for the identification of high-risk regions and the design of agricultural nutrient management policy. We investigate how pollution risk can be minimized by adopting simple irrigation and fertilization methods. Furthermore, we show that these methods are more effective for the most permeable soil profiles along with high demanding crops in terms of fertilization amount and irrigation water. We also present how seasonal (winter) climate conditions contribute on nitrate leaching.

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

    Science.gov (United States)

    Ng, Philip CH

    2010-01-01

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

  12. Design and Installation of Irrigation System for the Expansion of Sugar cane- Industries in Ahvaz, IRAN.

    Science.gov (United States)

    Afshari, E.; Afshari, S.

    2005-12-01

    This paper presents achievements of a twelve years ongoing project expansion of sugar cane- industries as a major agricultural development in Ahvaz, IRAN. The entire project is divided in to seven units and each unit provides irrigation water for 30,000 acres of sugar cane farms in Ahwaz. Absou Inc. is one of the consulting firms that is in charge of design and overseeing installation of irrigation system as well as the development of lands for sugar-cane cultivation at one of the units, called Farabi unit .In general, the mission of project is to Pump fresh water from Karoon River and direct it to the sugar cane farm for irrigation. In particular, the task of design and installation include, (1) build a pumping station at Karoon River with capacity of 1271 ft3/sec, (2) transfer water by main channel from Karoon rive to the farm site 19 miles (3) install a secondary pumping stations which direct water from main channel to drainage pipes and provides water for local farms (4) build a secondary channels which carries water with pipe lines with total length of 42 miles and diameter of 16 to 32 inch. (5) install drainage pump stations and collectors (6) level the ground surface and prepare it for irrigation (7) build railroad for carrying sugar canes (23 miles). Thus far, more than 15,000 acres of farm in Farabi unit is under sugar cane cultivation. The presentation will illustrate more details about different aspects of the project including design, installation and construction phases.

  13. Evaluation of water productivity under climate change in irrigated areas of the arid Northwest China using an assemble statistical downscaling method and an agro-hydrological model

    Science.gov (United States)

    Liu, Liu; Guo, Zezhong; Huang, Guanhua

    2018-06-01

    The Heihe River Basin (HRB) is the second largest inland river basin, located in the arid region of Northwest China with a serious water shortage. Evaluation of water productivity will provide scientific implications for agricultural water-saving in irrigated areas of the arid region under climate change. Based on observed meteorological data, 23 GCMs outputs and the ERA-40 reanalysis data, an assemble statistical downscaling model was developed to generate climate change scenarios under RCP2.6, RCP4.5, RCP8.5 respectively, which were then used to drive the SWAP-EPIC model to simulate crop growth in the irrigated areas of the middle HRB for the future period from 2018 to 2047. Crop yield showed an increasing trend, while crop water consumption decreased gradually in Gaotai and Ganzhou irrigated areas. The water productivity in future 30 years showed an increasing trend in both Gaotai and Ganzhou areas, with the most significant increase under RCP4.5 scenario, which were both larger than 2 kg m-3. Compared with that of the period from 2012 to 2015, the water productivity during 2018-2047 under three RCP scenarios increased by 9.2, 14.3 and 11.8 % in the Gaotai area, and 15.4, 21.6, 19.9 % in the Ganzhou area, respectively.

  14. Study Of Solar PV Sizing Of Water Pumping System For Irrigation Of Asparagus

    OpenAIRE

    Mya Su Kyi; Lu Maw; Hla Myo Tun

    2015-01-01

    The motivation for this system come from the countries where economy is depended on agriculture and the climatic conditions lead to lack of rains. The farmers working in the farm lands are dependent on the rains and bore wells. Even if the farm land has a water-pump manual involvement by farmers is required to turn the pump onoff when on earth needed. This paper presents design and calculation analysis of efficient Solar PV water pumping system for irrigation of Asparagus. The study area fall...

  15. Accumulation of heavy metal in scalp hair of people exposed in Beijing sewage discharge channel sewage irrigation area in Tianjin, China.

    Science.gov (United States)

    Wang, Zuwei; Yu, Xiaoman; Geng, Mingshuo; Wang, Zilu; Wang, Qianqian; Zeng, Xiangfeng

    2017-05-01

    Heavy metal concentrations in soil, wheat, and scalp hair exposed to Beijing sewage discharge channel sewage irrigation area (BSIA) in Tianjin were studied to evaluate the influence of sewage irrigation. Results showed that the continuous application of wastewater has led to an accumulation of heavy metals in the soil, with 55.2 and 8.62% of soil samples accumulating Cd and Zn, respectively, at concentrations exceeding the permissible limits in China. Concentrations of heavy metals in wheat grain from BSIA were higher than these from the clean water irrigation area by 63.2% for Cd, 3.8% for Cu, 100% for Pb, 6.6% for Zn, and 326.7% for Cr. The heavy metal bioaccumulation factor (BAF) of wheat/soil in BSIA showed the following order: Zn > Cd > Cu > Pb > Cr. Interestingly, these accumulation of heavy metals in soil after sewage irrigation could increase the migration ability of heavy metals (particularly Zn and Cd) from soil to wheat. Mean concentrations of heavy metals in the hair of residents followed the decreasing trend of Zn > Cu > Pb > Cr > Cd, which were higher than the control area by 110.0% for Cd, 20.0% for Cu, 55.9% for Zn, 36.6% for Pb, and 64.6% for Cr. Concentrations of heavy metals in male human hair in BSIA were higher than those of females. And the concentrations of heavy metals except for Pb in human hair increased with their increasing ages. The heavy metal BAF values of wheat/soil in BSIA showed the trend of Zn (98.0057) > Pb (7.0162) > Cr (5.5788) > Cu (5.4853) > Cd (3.5584); heavy metals had obvious biological amplification from wheat to human hair. These results indicated that local population health was potentially exposed to the heavy metal risk via wheat consumption.

  16. Grain Yield and Water Use Efficiency in Extremely-Late Sown Winter Wheat Cultivars under Two Irrigation Regimes in the North China Plain.

    Directory of Open Access Journals (Sweden)

    Bin Wang

    Full Text Available Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP. In recent years, winter wheat has been increasingly sown extremely late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE and guide the extremely late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike. Wheat was sown in early to mid-November at a high seeding rate of 800-850 seeds m(-2. Average yields of 7.42 t ha(-1 and WUE of 1.84 kg m(-3 were achieved with an average seasonal evapotranspiration (ET of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW and harvest index (HI. Among the 3 cultivars, JM22 had 5.9%-8.9% higher yield and 4.2%-9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in extremely late-sown winter wheat at a high seeding rate in the NCP.

  17. Quantitative evaluation of apical extrusion of debris and irrigants using four rotary instrumentation systems: an in vitro study.

    Science.gov (United States)

    Nagaveni, S Aspalli; Balakoti, K Reddy; Smita, Karan; Ratnakar, P; Satish, S V; Aravind, T

    2013-11-01

    The apical extrusion of infected debris may have the potential to disrupt the balance between microbial aggression and host defense, resulting in incidents of acute inflammation. During preparation, irrigants and debris, such as bacteria, dentin filings and necrotic tissue may be extruded into the periradicular region leading to periapical inflammation and postoperative flare ups. Using an instrumentation technique that minimizes apical extrusion would be beneficial to both the practitioner and patient. The purpose of the study was to evaluate the weight of debris and volume of irrigant extruded apically from extracted teeth in vitro after endodontic instrumentation using four different rotary root canal instrumentation systems. Four groups of each 20 extracted mandibular premolars were instrumented using one of the four systems: ProTaper Universal (Dentsply Maillefer, Ballaigues, Switzerland)), Hero-shaper (MicroMega, Besancon, France), RaCe (FKG Dentaire, La-Chaux-de-Fonds, Switzerland) and K3 (SybronEndo, West Collins, CA). Debris and irrigant extruded from the apical foramen during instrumentation were collected in preweighed test tubes. Volume of irrigant extruded was noted. The containers were stored in incubator at 70° for two days to evaporate the moisture. Weight of dry debris was noted. Data was analyzed using Kruskall-Wallis and Mann-Whitney U test at a significance of 0.001. The results indicated that all of the instrumentation systems tested caused measurable apical extrusion of debris and irrigants. Higher extrusion was observed with Protaper system which was statistically significant with Hero-Shaper, RaCe and K3 systems. There were no statistical differences between Hero-shaper, K3 and RaCe systems (p < 0.05). All instrumentation techniques apically extruded debris and irrigant. However, Hero-shaper, K3 and RaCe systems produced less extruded debris and irrigant than the Protaper system.

  18. A Quantitative Socio-hydrological Characterization of Water Security in Large-Scale Irrigation Systems

    Science.gov (United States)

    Siddiqi, A.; Muhammad, A.; Wescoat, J. L., Jr.

    2017-12-01

    Large-scale, legacy canal systems, such as the irrigation infrastructure in the Indus Basin in Punjab, Pakistan, have been primarily conceived, constructed, and operated with a techno-centric approach. The emerging socio-hydrological approaches provide a new lens for studying such systems to potentially identify fresh insights for addressing contemporary challenges of water security. In this work, using the partial definition of water security as "the reliable availability of an acceptable quantity and quality of water", supply reliability is construed as a partial measure of water security in irrigation systems. A set of metrics are used to quantitatively study reliability of surface supply in the canal systems of Punjab, Pakistan using an extensive dataset of 10-daily surface water deliveries over a decade (2007-2016) and of high frequency (10-minute) flow measurements over one year. The reliability quantification is based on comparison of actual deliveries and entitlements, which are a combination of hydrological and social constructs. The socio-hydrological lens highlights critical issues of how flows are measured, monitored, perceived, and experienced from the perspective of operators (government officials) and users (famers). The analysis reveals varying levels of reliability (and by extension security) of supply when data is examined across multiple temporal and spatial scales. The results shed new light on evolution of water security (as partially measured by supply reliability) for surface irrigation in the Punjab province of Pakistan and demonstrate that "information security" (defined as reliable availability of sufficiently detailed data) is vital for enabling water security. It is found that forecasting and management (that are social processes) lead to differences between entitlements and actual deliveries, and there is significant potential to positively affect supply reliability through interventions in the social realm.

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

    Science.gov (United States)

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

    2012-12-01

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

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

    Science.gov (United States)

    Wang, Y.

    2015-12-01

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

  1. Water Governance and Adaptation to Disturbances in Irrigated Semi-Arid Agricultural Systems

    Science.gov (United States)

    Evans, T. P.; McCord, P. F.; McBride, L.; Gower, D.; Caylor, K. K.

    2013-12-01

    Climate and other physical drivers of environmental systems are modifying the global availability of water for irrigation. At the same time population growth is placing an increased demand on water resources as local municipalities promote agricultural production as a mechanism to support human welfare and development. Substantial has research focused on household-level agricultural decision-making and adaptation. But equally important are institutional dynamics, or the rules implemented to allocate water resources across different user groups. Previous work has identified design principles for common-pool resource systems that tend to lead to sustained governance regimes. Likewise, past research has addressed the issue of "institutional fit", or locally adapted governance arrangements characterized through governance structure. However, much of the complexity behind institutional dynamics and adaptive capacity lies in the translation of data to information to knowledge, and how this sequence contributes to effective cross-scale water management and decision-making - an arena that has arguably received less attention in the water management literature. We investigate the interplay between governance regimes, data/information and institutional dynamics in irrigation systems in semi-arid regions of Kenya. In particular, we articulate the role of knowledge and data in institutional dynamics at multiple levels of analysis. How do users at different decision-making levels incorporate social and hydrological information in water governance? What data is needed to develop the information and knowledge users need for effective management? While governance structure is certainly a critical component of water management systems - we emphasize the interplay between the data-information-knowledge sequence and institutional dynamics. We present findings from household and manager-level surveys examining irrigation practices and the institutions designed to equitably allocate

  2. Antibacterial Efficacy of Calcium Hypochlorite with Vibringe Sonic Irrigation System on Enterococcus faecalis: An In Vitro Study

    Science.gov (United States)

    Dumani, Aysin; Guvenmez, Hatice Korkmaz; Yilmaz, Sehnaz; Yoldas, Oguz; Kurklu, Zeliha Gonca Bek

    2016-01-01

    Aim. The purpose of this study was to compare the in vitro efficacy of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with sonic (Vibringe) irrigation system in root canals which were contaminated with Enterococcus faecalis. Material and Methods. The root canals of 84 single-rooted premolars were enlarged up to a file 40, autoclaved, inoculated with Enterococcus faecalis, and incubated for 21 days. The samples were divided into 7 groups according to the irrigation protocol: G0: no treatment; G1: distilled water; G2: 2.5% NaOCl; G3: 2.5% Ca(OCl)2; G4: distilled water with sonic activation; G5: 2.5% NaOCl with sonic activation; and G6: 2.5% Ca(OCl)2 with sonic activation. Before and after decontamination procedures microbiological samples were collected and the colony-forming units were counted and the percentages of reduction were calculated. Results. Distilled water with syringe irrigation and sonic activation groups demonstrated poor antibacterial effect on Enterococcus faecalis compared to other experimental groups (p irrigation systems with Ca(OCl)2 and NaOCl. Conclusion. The antimicrobial property of Ca(OCl)2 has been investigated and compared with that of NaOCl. Both conventional syringe irrigation and sonic irrigation were found effective at removing E. faecalis from the root canal of extracted human teeth. PMID:27218106

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

    Science.gov (United States)

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

    1975-01-01

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

  4. Detection of Anthropogenic pressures on western Mediterranean irrigation systems (La Albufera de Valencia agriculture system, eastern Spain)

    Science.gov (United States)

    Pascual-Aguilar, J. A.; Andreu, V.; Picó, Y.

    2012-04-01

    Irrigation systems are considered as one of the major landscapes features in western Mediterranean environments. Both socio-economic and cultural elements are interrelated in their development and preservation. Generally, due to their location in flat lands and close to major urban-industrial zones, irrigation lands are suffering of intense pressures that can alter their agricultural values, environmental quality and, consequently, the sustainability of the systems. To understand the nature of anthropogenic pressures on large Mediterranean water agricultural systems a methodology based on environmental forensics criteria has been developed and applied to La Albufera Natural Park in Valencia (Eastern Spain), a protected area where traditional irrigation systems exists since Muslim times (from 8th to 15th centuries). The study analysed impacts on water and soils, for the first case the fate of emerging contaminants of urban origin (pharmaceuticals and illegal drugs) are analysed. Impact on soils is analysed using the dynamics urban expansion and the loss and fragmentation of soils. The study focused is organised around two major procedures: (1) analysis of 16 water samples to identify the presence of 14 illicit drugs and 17 pharmaceutical compounds by Liquid Chromatography-Mass Spectrometry techniques; (2) spatial analysis with Geographical Information Systems (GIS) integrating different sources and data formats such as water analysis, social, location of sewage water treatment plan and the synchronic comparison of two soil sealing layers -for the years 1991 and 2010. Results show that there is a clear trend in the introduction of pharmaceutical in the irrigation water through previous use of urban consumption and, in many cases, for receiving the effluents of wastewaters treatment plants. Impacts on soils are also important incidence in the fragmentation and disappearance of agricultural land due to soil sealing, even within the protected area of the Natural Park

  5. Obstruction and uniformity in drip irrigation systems by applying treated wastewater

    Directory of Open Access Journals (Sweden)

    Patrícia Ferreira da Silva

    Full Text Available ABSTRACT The use of wastewater in agriculture is an alternative to control surface water pollution, and helps to promote the rational use of water. Therefore, the objective of this study was to evaluate the obstruction and uniformity of application of treated wastewater in drip irrigation systems. The study was conducted in a greenhouse at the Universidade Federal de Campina Grande. The treatments were composed by the factorial combination of two factors: three types of water (supply water-ABAST, effluent of a constructed wetland system -WETLAND and upflow of anaerobic reactor effluent followed by constructed wetland system -UASB + WETLAND, and two drip irrigation systems (surface and subsurface, set in a completely randomized design, with four replications. The results indicated that the pH, suspended solids, total iron and coliforms of the WETLAND and UASB + WETLAND treatments represented a severe risk of clogging of drippers; the flow of the emitters increased as the service pressure was increased; values of CUC and CUD in surface and subsurface drip were classified as excellent in ABAST and WETLAND treatments. The degree of clogging reduced as pressure under surface and subsurface drip was increased.

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

    Directory of Open Access Journals (Sweden)

    Alma Delia González

    2017-12-01

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

  7. Financial stability of banking system in China

    OpenAIRE

    Jiang, B

    2014-01-01

    This thesis aims at investigating the financial stability of China's banking system. Since the banking system is one of the most important financial intermediaries in the financial systems, the financial soundness of banks could secure the stability of the whole financial system. Two of the factors that may significantly increase imbalance of the banking system, and hence affect financial stability of an economy is the accumulated non-performing loans of banks and the macro-economic turbulenc...

  8. Changes in the potential multiple cropping system in response to climate change in China from 1960-2010.

    Science.gov (United States)

    Liu, Luo; Xu, Xinliang; Zhuang, Dafang; Chen, Xi; Li, Shuang

    2013-01-01

    The multiple cropping practice is essential to agriculture because it has been shown to significantly increase the grain yield and promote agricultural economic development. In this study, potential multiple cropping systems in China are calculated based on meteorological observation data by using the Agricultural Ecology Zone (AEZ) model. Following this, the changes in the potential cropping systems in response to climate change between the 1960s and the 2010s were subsequently analyzed. The results indicate that the changes of potential multiple cropping systems show tremendous heterogeneity in respect to the spatial pattern in China. A key finding is that the magnitude of change of the potential cropping systems showed a pattern of increase both from northern China to southern China and from western China to eastern China. Furthermore, the area found to be suitable only for single cropping decreased, while the area suitable for triple cropping increased significantly from the 1960s to the 2000s. During the studied period, the potential multiple cropping index (PMCI) gap between rain-fed and irrigated scenarios increased from 18% to 24%, which indicated noticeable growth of water supply limitations under the rain-fed scenario. The most significant finding of this research was that from the 1960s to the 2000s climate change had led to a significant increase of PMCI by 13% under irrigated scenario and 7% under rain-fed scenario across the whole of China. Furthermore, the growth of the annual mean temperature is identified as the main reason underlying the increase of PMCI. It has also been noticed that across China the changes of potential multiple cropping systems under climate change were different from region to region.

  9. Solar Thermal System Evaluation in China

    Directory of Open Access Journals (Sweden)

    Xinyu Zhang

    2015-01-01

    Full Text Available More than 581 solar thermal systems (STSs, 98 counties, and 47 renewable application demonstration cites in China need to be inspected by the end of 2015. In this study, the baseline for performance and economic evaluation of STSs are presented based on the site test data and related references. An index used to evaluate STSs was selected, and methods to acquire the parameters used to calculate the related index were set. The requirements for sensors for testing were specified. The evaluation method was applied to three systems and the result shows that the evaluation method is suitable for the evaluation of STSs in China.

  10. A Computer Program for Drip Irrigation System Design for Small Plots

    Science.gov (United States)

    Philipova, Nina; Nicheva, Olga; Kazandjiev, Valentin; Chilikova-Lubomirova, Mila

    2012-12-01

    A computer programhas been developed for design of surface drip irrigation system. It could be applied for calculation of small scale fields with an area up to 10 ha. The program includes two main parts: crop water requirements and hydraulic calculations of the system. It has been developed in Graphical User Interface in MATLAB and gives opportunity for selecting some parameters from tables such as: agro- physical soil properties, characteristics of the corresponding crop, climatic data. It allows the user of the program to assume and set a definite value, for example the emitter discharge, plot parameters and etc. Eight cases of system layout according to the water source layout and the number of plots of the system operation are laid into hydraulic section of the program. It includes the design of lateral, manifold, main line and pump calculations. The program has been compiled to work in Windows.

  11. Appropriate rehabilitation strategy for a traditional irrigation supply system: a case from the Babai area in Nepal.

    Science.gov (United States)

    Adhikari, B; Verhoeven, R; Troch, P

    2009-01-01

    This paper studies primary canals of three traditional irrigation systems in the southern plains of Nepal. It offers a scientific interpretation of the indigenous technology applied to the systems, which facilitates to use the same channel network for irrigation, drainage and flood management. The flood management technology of the farmers by diverting as much discharge as possible to the field channels results in the reduction of discharge towards the downstream part of the main channel. It is depicted in the simulation study that uses the river analysis program HEC-RAS 4.0. A cascade of weirs is found to be the most cost effective and user-friendly option to upgrade these systems preserving the existing irrigation, drainage as well as flood management functions. This study suggests that the conventional irrigation design principles should be applied very cautiously with full knowledge of the existing socio-institutional setting, hydro-ecological regime and indigenous technology for upgrading any traditional irrigation system successfully. The indigenous flood management technology strengthens the emerging concept that the floods in the Ganges plain are to be managed, not controlled.

  12. Optimization Strategy for Improving the Energy Efficiency of Irrigation Systems by Micro Hydropower: Practical Application

    Directory of Open Access Journals (Sweden)

    Modesto Pérez-Sánchez

    2017-10-01

    Full Text Available Analyses of possible synergies between energy recovery and water management are essential for achieving sustainable advances in the performance of pressurized irrigation networks. Nowadays, the use of micro hydropower in water systems is being analysed to improve the overall energy efficiency. In this line, the present research is focused on the proposal and development of a novel optimization strategy for increasing the energy efficiency in pressurized irrigation networks by energy recovering. The recovered energy is maximized considering different objective functions, including feasibility index: the best energy converter must be selected, operating in its best efficiency conditions by variation of its rotational speed, providing the required flow in each moment. These flows (previously estimated through farmers’ habits are compared with registered values of flow in the main line with very suitable calibration results, getting a Nash–Sutcliffe value above 0.6 for different time intervals, and a PBIAS index below 10% in all time interval range. The methodology was applied to a Vallada network obtaining a maximum recovered energy of 58.18 MWh/year (41.66% of the available energy, improving the recovered energy values between 141 and 184% when comparing to energy recovery considering a constant rotational speed. The proposal of this strategy shows the real possibility of installing micro hydropower machines to improve the water–energy nexus management in pressurized systems.

  13. Co-benefits and trade-offs in the water-energy nexus of irrigation modernization in China

    Science.gov (United States)

    Cremades, Roger; Rothausen, Sabrina G. S. A.; Conway, Declan; Zou, Xiaoxia; Wang, Jinxia; Li, Yu'e.

    2016-05-01

    There are strong interdependencies between water use in agriculture and energy consumption as water saving technologies can require increased pumping and pressurizing. The Chinese Government includes water efficiency improvement and carbon intensity reduction targets in the 12th Five-Year Plan (5YP. 2011-2015), yet the links between energy use and irrigation modernization are not always addressed in policy targets. Here we build an original model of the energy embedded in water pumping for irrigated agriculture and its related processes. The model is based on the physical processes of irrigation schemes and the implication of technological developments, comprising all processes from extraction and conveyance of water to its application in the field. The model uses data from government sources to assess policy targets for deployment of irrigation technologies, which aim to reduce water application and contribute to adaptation of Chinese agriculture to climate change. The consequences of policy targets involve co-beneficial outcomes that achieve water and energy savings, or trade-offs in which reduced water application leads to increasing greenhouse gas (GHG) emissions. We analyze irrigation efficiency and energy use in four significant provinces and nationally, using scenarios based on the targets of the 12th 5YP. At the national scale, we find that expansion of sprinklers and micro-irrigation as outlined in the 5YP would increase GHG emissions from agricultural water use, however, emissions decrease in those provinces with predominant groundwater use and planned expansion of low-pressure pipes. We show that the most costly technologies relate to trade-offs, while co-benefits are generally achieved with less expensive technologies. The investment cost per area of irrigation technology expansion does not greatly affect the outcome in terms of water, but in terms of energy the most expensive technologies are more energy-intensive and produce more emissions. The

  14. Influence of a passive sonic irrigation system on the elimination of bacteria from root canal systems: a clinical study.

    Science.gov (United States)

    Huffaker, S Kirk; Safavi, Kamran; Spangberg, Larz S W; Kaufman, Blythe

    2010-08-01

    The present investigation evaluated the ability of a new passive sonic irrigation (sonic group) system (EndoActivator) to eliminate cultivable bacteria from root canals in vivo and compared it with that of standard syringe irrigation (control group). Data were obtained by using bacteriologic sampling of root canals treated by endodontic residents. Sampling results from 1 session of treatment were then compared with results obtained after intervisit calcium hydroxide disinfection and a second session of treatment. There was no significant difference in the ability of sonic group and control group to eliminate cultivable bacteria from root canals (P > .05). A second session and intervisit calcium hydroxide disinfection were able to eliminate cultivable bacteria from significantly more teeth than a single session of treatment (P treatment of apical periodontitis. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-01

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

  16. Efficiency optimization of a photovoltaic water pumping system for irrigation in Ouargla, Algeria

    Science.gov (United States)

    Louazene, M. L.; Garcia, M. C. Alonso; Korichi, D.

    2017-02-01

    This work is technical study to contribute to the optimization of pumping systems powered by solar energy (clean) and used in the field of agriculture. To achieve our goals, we studied the techniques that must be entered on a photovoltaic system for maximum energy from solar panels. Our scientific contribution in this research is the realization of an efficient photovoltaic pumping system for irrigation needs. To achieve this and extract maximum power from the PV generator, two axes have been optimized: 1. Increase in the uptake of solar radiation by choice an optimum tilt angle of the solar panels, and 2. it is necessary to add an adaptation device, MPPT controller with a DC-DC converter, between the source and the load.

  17. Increased water charges improve efficiency and equity in an irrigation system

    Directory of Open Access Journals (Sweden)

    Andrew Reid. Bell

    2016-09-01

    Full Text Available Conventional wisdom in many agricultural systems across the world is that farmers cannot, will not, or should not pay the full costs associated with surface water delivery. Across Organisation for Economic Co-operation and Development (OECD countries, only a handful can claim complete recovery of operation, maintenance, and capital costs; across Central and South Asia, fees are lower still, with farmers in Nepal, India, and Kazakhstan paying fractions of a U.S. penny for a cubic meter of water. In Pakistan, fees amount to roughly USD 1-2 per acre per season. However, farmers in Pakistan spend orders of magnitude more for diesel fuel to pump groundwater each season, suggesting a latent willingness to spend for water that, under the right conditions, could potentially be directed toward water-use fees for surface water supply. Although overall performance could be expected to improve with greater cost recovery, asymmetric access to water in canal irrigation systems leaves the question open as to whether those benefits would be equitably shared among all farmers in the system. We develop an agent-based model (ABM of a small irrigation command to examine efficiency and equity outcomes across a range of different cost structures for the maintenance of the system, levels of market development, and assessed water charges. We find that, robust to a range of different cost and structural conditions, increased water charges lead to gains in both efficiency and concomitant improvements in equity as investments in canal infrastructure and system maintenance improve the conveyance of water resources further down watercourses. This suggests that, under conditions in which (1 farmers are currently spending money to pump groundwater to compensate for a failing surface water system, and (2 there is the possibility that through initial investment to provide perceptibly better water supply, genuine win-win solutions can be attained through higher water-use fees to

  18. Efficient Maize and Sunflower Multi-year Mapping with NDVI Time Series of HJ-1A/1B in Hetao Irrigation District of Inner Mongolia, China

    Science.gov (United States)

    Yu, B.; Shang, S.

    2016-12-01

    Food shortage is one of the major challenges that human beings are facing. It is urgent to improve the monitoring of the plantation and distribution of the main crops to solve the following economic and social issues. Recently, with the extensive use of remote sensing satellite data, it has provided favorable conditions for crop identification in large irrigation district with complex planting structure. Difference of different crop phenology is the main basis for crop identification, and the normalized difference vegetation index (NDVI) time-series could better delineate crop phenology cycle. Therefore, the key of crop identification is to obtain high quality NDVI time-series. MODIS and Landsat TM satellite images are the most frequently used, however, neither of them could guarantee high temporal and spatial resolutions at once. Accordingly, this paper makes use of NDVI time-series extracted from China Environment Satellites data, which has two-day-repeat temporal and 30m spatial resolutions. The NDVI time-series are fitted with an asymmetric logistic curve, the fitting effect is good and the correlation coefficient is greater than 0.9. The phonological parameters are derived from NDVI fitting curves, and crop identification is carried out by different relation ellipses between NDVI and its phonological parameters of different crops. This paper takes Hetao Irrigation District of Inner Mongolia as an example, to identify multi-year maize and sunflower in the district, and the identification result is good. Compared with the official statistics, the relative errors are both lower than 5%. The results show that the NDVI time-series dataset derived from HJ-1A/1B CCD could delineate the crop phenology cycle accurately and demonstrate its application in crop identification in irrigated district.

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

    Directory of Open Access Journals (Sweden)

    Duke M. Bulanon

    2016-06-01

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

  20. Simulating the reactive transport of nitrogen species in a regional irrigated agricultural groundwater system

    Science.gov (United States)

    Bailey, R. T.; Gates, T. K.

    2011-12-01

    The fate and transport of nitrogen (N) species in irrigated agricultural groundwater systems is governed by irrigation patterns, cultivation practices, aquifer-surface water exchanges, and chemical reactions such as oxidation-reduction, volatilization, and sorption, as well as the presence of dissolved oxygen (O2). We present results of applying the newly-developed numerical model RT3D-AG to a 50,400-ha regional study site within the Lower Arkansas River Valley in southeastern Colorado, where elevated concentrations of NO3 have been observed in both groundwater and surface water during the recent decade. Furthermore, NO3 has a strong influence on the fate and transport of other contaminants in the aquifer system such as selenium (Se) through inhibition of reduction of dissolved Se as well as oxidation of precipitate Se from outcropped and bedrock shale. RT3D-AG, developed by appending the multi-species reactive transport finite-difference model RT3D with modular packages that account for variably-saturated transport, the cycling of carbon (C) and N, and the fate and transport of O2 within the soil and aquifer system, simulates organic C and organic N decomposition and mineralization, oxidation-reduction reactions, and sorption. System sources/sinks consist of applied fertilizer and manure; crop uptake of ammonium (NH4) and NO3 during the growing season; mass of O2, NO3, and NH4 associated with irrigation water and canal seepage; mass of O2, NO3, and NH4 transferred to canals and the Arkansas River from the aquifer; and dead root mass and after-harvest stover mass incorporated into the soil organic matter at the end of the growing season. Chemical reactions are simulated using first-order Monod kinetics, wherein the rate of reaction is dependent on the concentration of the reactants as well as temperature and water content of the soil. Fertilizer and manure application timing and loading, mass of seasonal crop uptake, and end-of-season root mass and stover mass are

  1. Impacts of changing cropping pattern on virtual water flows related to crops transfer: a case study for the Hetao irrigation district, China.

    Science.gov (United States)

    Liu, Jing; Wu, Pute; Wang, Yubao; Zhao, Xining; Sun, Shikun; Cao, Xinchun

    2014-11-01

    Analysis of cropping patterns is a prerequisite for their optimisation, and evaluation of virtual water flows could shed new light on water resources management. This study is intended to explore the effects of cropping pattern changes between 1960 and 2008 on virtual water flows related to crops transfer in the Hetao irrigation district, China. (1) The sown area of crops increased at an average rate of 3.57 × 10(3) ha year(-1) while the proportion of sown grain crops decreased from 92.83% in the 1960s to 50.22% in the 2000s. (2) Virtual water content decreased during the study period while net virtual water exports increased since the 1980s. (3) Assuming that the cropping pattern was constant and was equal to the average 1960s value, accumulated net virtual water export in 1980-2008 would have been 4.76 × 10(9) m(3) greater than that in the actual cropping pattern scenario. Cropping pattern changes in the Hetao irrigation district could not only be seen as resulting from the pursuit for higher economic returns, but also as a feedback response to limited water resources. A systematic framework is still needed for future cropping pattern planning by taking food security, continued agricultural expansion and other constraints into consideration. © 2014 Society of Chemical Industry.

  2. Water Use Efficiency under Different Tillage and Irrigation Systems for Tomato Farming in Southeastern Brazil

    Science.gov (United States)

    Bhering, S. B.; Fernandes, N. F.; Macedo, J. R.

    2009-04-01

    highly degrade the environment, applied without practices of soil and water conservation. Such production systems are associated with a variety of environmental problems, such as soil erosion, the extensive pumping of groundwater, the partial obstruction of surface drainage to form artificial lakes, the contamination of groundwater, among others. The environmental impacts generated by all these problems assume a greater importance due to the complete absence of monitoring the continuous lowering of the water table and the changes in water quality. We consider that the main management strategies for developing sustainable production systems for the tomato farming in this area should be based on monitoring water use efficiency, increasing water availability in the root zone and also preventing runoff, leaching and evaporation of water from the soil. Therefore, techniques were applied as green manures with legumes without incorporation of the biomass, non-mechanized and curve-level soil preparation, planting in level, soil cover with crop residues, fertirrigation with solid fertilization of low value, the conduct of tomato especially supported by plastic string attached to a trellis, drip irrigation, and monitoring soil water potential (SWP) with Watermak sensors. At the end of the tomato cycle, water use efficiency and the productivity were compared at 8 micro-plots installed in the 3 studied production systems: conventional tillage (CT-H), minimum tillage (MT-H), both with "wetting irrigation with garden hose", and no-tillage with drip irrigation (NT-D). For each production system, soil physical properties were characterized and soil water potential (SWP) and soil temperature were continuously monitored at different depths (20, 40, 60 and 80 cm), as well as the total water volume used in each irrigation. In parallel, we also compared the development of the root system and the final productivity for each one of the three production systems. The results obtained in this

  3. Apical extrusion of debris and irrigants using hand and three rotary instrumentation systems- An in vitro study

    Directory of Open Access Journals (Sweden)

    Koppolu Madhusudhana

    2010-01-01

    Full Text Available Introduction: Sterilization of the root canal is a prime aim of successful endodontics. The cleaning and shaping of the canal is directed as achieving this goal. The extrusion of apical debris has a deleterious effect on the prognosis of root canal treatment. Several instrument designs and instrumentation techniques have been developed to prevent this. Materials and Methods: Forty caries free single rooted human mandibular premolar teeth were divided in four groups of ten teeth each. Teeth in each group were instrumented until the working length with rotary ProTaper, K3, Mtwo systems, and hand K-type stainless steel files. Debris and irrigant extruded from the apical foramen were collected into vials and the amounts were quantitatively determined. The data obtained were analyzed using Kruskal-Wallis one-way analysis of variance and Mann-Whitney U tests. Results: The results show that all instrumentation techniques produced significant amount of extruded debris and irrigant. The engine-driven nickel-titanium systems showed less apical extrusion of debris and irrigant than manual technique. No statistically significant difference was found between the groups at [P > 0.05]. Maximum apical debris and irrigant extrusion was seen with K-file group and least in the Mtwo group. Conclusions: The use of rotary files and techniques to perform instrumentation does show less extrusion of the debris and irrigant from the apex. This can contribute to more successful endodontic therapy.

  4. Apical extrusion of debris and irrigants using hand and three rotary instrumentation systems − An in vitro study.

    Science.gov (United States)

    Madhusudhana, Koppolu; Mathew, Vinod Babu; Reddy, Nelaturi Madhusudhan

    2010-10-01

    Sterilization of the root canal is a prime aim of successful endodontics. The cleaning and shaping of the canal is directed as achieving this goal. The extrusion of apical debris has a deleterious effect on the prognosis of root canal treatment. Several instrument designs and instrumentation techniques have been developed to prevent this. Forty caries free single rooted human mandibular premolar teeth were divided in four groups of ten teeth each. Teeth in each group were instrumented until the working length with rotary ProTaper, K3, Mtwo systems, and hand K-type stainless steel files. Debris and irrigant extruded from the apical foramen were collected into vials and the amounts were quantitatively determined. The data obtained were analyzed using Kruskal-Wallis one-way analysis of variance and Mann-Whitney U tests. The results show that all instrumentation techniques produced significant amount of extruded debris and irrigant. The engine-driven nickel-titanium systems showed less apical extrusion of debris and irrigant than manual technique. No statistically significant difference was found between the groups at [P > 0.05]. Maximum apical debris and irrigant extrusion was seen with K-file group and least in the Mtwo group. The use of rotary files and techniques to perform instrumentation does show less extrusion of the debris and irrigant from the apex. This can contribute to more successful endodontic therapy.

  5. Energetic expense in the conduction of the physic nut culture: comparative between the dried and irrigated system

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, Michelle Sato; Frigo, Elisandro Pires; Klar, Antonio Evaldo; Bueno, Osmar de Carvalho; Esperancini, Maura Seiko Tsuitsui [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas], E-mail: msfrigo@fca.unesp.br

    2008-07-01

    The discussion around new vegetable raw materials for biofuel, production have been being very important for the consolidation of the National Program of Biofuel Production and Use (PNPB) in Brazil. In this scenery, a potential culture which could be pointed for such a thing is the physic nut one, however, the studies about it are very poor. Thus the goal of this present paper was to compare the energetic expense to this culture conduction, in two different productive systems, the dried and the irrigated ones, so as to identify the less dependent system on not-renewable energy, therefore, the most energetically sustainable one for these conduction operations. The selected planting was one of the areas of the company NNE Minas Agro-Florestal Ltda., in Janauba/MG; there were identified two operations for the dried system and four operations for the irrigated system. The adopted methodology was based in bibliographical revision. The dried system showed an energetic consumption of 1.151,22 MJ. ha{sup -1} and the irrigated one was 5.325,43 MJ . ha{sup -1}. In relation to the expenditure by source, the dried one used 2,72% by biological source and 97,28% by industrial source; and the irrigated system used 0,87% by biological source and 99,14% by industrial source. The conclusion is that the conduction with the dried system is the most efficient and sustainable from the energetic point of view. (author)

  6. Delivering power system transition in China

    International Nuclear Information System (INIS)

    Yuan Jiahai; Xu Yan; Hu Zhaoguang

    2012-01-01

    This paper studies the transition to low carbon power systems in China. The methodology is built on the newly developed multi-level perspective (MLP) transitions, as well as literature on innovation systems. Three lines of thought on the transition process are integrated to probe the possible transition pathways in China's power sector. Five transition pathways, namely reproduction, transformation, substitution, reconfiguration, de-alignment/re-alignment and reconfiguration, with their possible technology options are presented. The requirements for a smart grid in the socio-technical transition process are addressed within the MLP framework. The paper goes further to propose an interactive framework for low carbon transition management in China. Representative technology options are appraised by employing innovation theory to demonstrate the logic of policy design within the framework. The work presented in this paper will be useful in informing policy-makers and other stakeholders in China and it may prove to be a valuable reference for other countries in energy transition management. - Highlights: ► The transition to low carbon power systems is studied from a multi-level perspective. ► Transition pathways with possible technology options are presented. ► An interactive framework is proposed for managing this transition. ► Representative technology options are appraised within the framework to show the logic of policy design.

  7. Results of infected total knee arthroplasty treated with arthroscopic debridement and continuous antibiotic irrigation system

    Directory of Open Access Journals (Sweden)

    Che-Wei Liu

    2013-01-01

    Conclusion: Arthroscopic debridement combined with continuous antibiotic irrigation and suction is an effective treatment for patients with acute presentation of late infected total knee arthroplasty.

  8. Calibration Curve of Neutron Moisture Meter for Sandy Soil under Drip Irrigation System

    International Nuclear Information System (INIS)

    Mohammad, Abd El- Moniem M.; Gendy, R. W.; Bedaiwy, M. N.

    2004-01-01

    The aim of this work is to construct a neutron calibration curve in order to be able to use the neutron probe in sandy soils under drip irrigation systems. The experimental work was conducted at the Soil and Water Department of the Nuclear Research Center, Atomic Energy Authority. Three replicates were used along the lateral lines of the drip irrigation system. For each dripper, ten neutron access tubes were installed to 100-cm depth at distances of 5, 15 and 25 cm from the dripper location around the drippers on the lateral line, as well as between lateral lines. The neutron calibrations were determined at 30, 45, and 60-cm depths. Determining coefficients as well as t-test in pairs were employed to detect the accuracy of the calibrations. Results indicated that in order for the neutron calibration curve to express the whole wet area around the emitter; three-access tubes must be installed at distances of 5, 15, and 25 cm from the emitter. This calibration curve will be correlating the average count ratio (CR) at the studied soil depth of the three locations (5, 15, and 25-cm distances from the emitter) to the average moisture content (θ) for this soil depth of the entire wetted area. This procedure should be repeated at different times in order to obtain different θ and C.R values, so that the regression equation of calibration curve at this soil depth can be obtained. To determine the soil moisture content, the average CR of the three locations must be taken and substituted into the regression equation representing the neutron calibration curve. Results taken from access tubes placed at distances of 15 cm from the emitter, showed good agreement with the average calibration curve both for the 45- and the 60-cm depths, suggesting that the 15-cm distance may provide a suitable substitute for the simultaneous use of the three different distances of 5, 15 and 25 cm. However, the obtained results show also that the neutron calibration curves of the 30-cm depth for

  9. Technical and economical evaluation of tape drip and drip line irrigation systems in a strawberry greenhouse

    Directory of Open Access Journals (Sweden)

    Soghra HOSSEINIAN

    2016-04-01

    Full Text Available This study was done in a strawberry greenhouse to examine the technical and the economical evaluation of two drip irrigation systems including the tape and the drip line in the northern part of Iran. The result showed that all of the technical indices with tape were higher than drip line, and due to statistical analysis reveal a significant difference (P < 0.05. Yield and water productivity (WP with tape were higher than drip line (P < 0.05. Benefit per drop (BPD and net benefit per drop (NBPD with tape were higher than drip line. Net present value, internal rate of capital return and benefit to cost ratio in drip line were higher than tape. In general, regarding technical evaluation tape was better than drip line, besides according to the economical evaluation the drip ­lines were better than tape.

  10. Learning from the Field: Innovating China's Higher Education System

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

    2008-04-15

    Apr 15, 2008 ... Learning from the Field: Innovating China's Higher Education System ... to translating China's higher education policy reforms into practice. The editors. Ronnie Vernooy is Senior Program Specialist, International Development ...

  11. Residue and soil carbon sequestration in relation to crop yield as affected by irrigation, tillage, cropping system and nitrogen fertilization

    Science.gov (United States)

    Information on management practices is needed to increase surface residue and soil C sequestration to obtain farm C credit. The effects of irrigation, tillage, cropping system, and N fertilization were evaluated on the amount of crop biomass (stems and leaves) returned to the soil, surface residue C...

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

    Science.gov (United States)

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

  13. Safe and high quality food production using low quality waters and improved irrigation systems and management

    DEFF Research Database (Denmark)

    Plauborg, Finn; Andersen, Mathias Neumann; Liu, Fulai

    2010-01-01

    uneven irrigation patterns can increase the water use efficiency as well as the quality of vegetable crops. Furthermore, recent innovations in the water treatment and irrigation industry have shown potential for the use of low quality water resources, such as reclaimed water or surface water in peri...

  14. Effectiveness of different irrigation systems on filling of simulated lateral canals

    Directory of Open Access Journals (Sweden)

    sehnaz Yilmaz

    2016-09-01

    Conclusions: Sonically or ultrasonically irrigation showed significant differences on the filling of the simulated lateral canals at the middle third of the root canals. Ultrasonic activation of the irrigants represented better results in radiographic and cleared specimen evaluation. [Cukurova Med J 2016; 41(3.000: 515-520

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

    Science.gov (United States)

    Southwestern US irrigated landscapes are facing upheaval due to water scarcity and land use conversion associated with climate change, population growth, and changing economics. In the traditionally irrigated valleys of northern New Mexico, these stresses, as well as instances of community longevity...

  16. Simulating selenium and nitrogen fate and transport in coupled stream-aquifer systems of irrigated regions

    Science.gov (United States)

    Shultz, Christopher D.; Bailey, Ryan T.; Gates, Timothy K.; Heesemann, Brent E.; Morway, Eric D.

    2018-01-01

    Elevated levels of selenium (Se) in aqueous environments can harm aquatic life and endanger livestock and human health. Although Se occurs naturally in the rocks and soils of many alluvial aquifers, mining and agricultural activities can increase its rate of mobilization and transport to surface waters. Attention is given here to regions where nonpoint source return flows from irrigated lands carry pollutant loads to aquifers and streams, contributing to concentrations that violate regulatory and performance standards. Of particular concern is the heightened level and mobilization of Se influenced by nitrate (NO3), a harmful pollutant in its own right. We present a numerical model that simulates the reactive transport of Se and nitrogen (N) species in a coupled groundwater-surface water system. Building upon a conceptual model that incorporates the major processes affecting Se and NO3 transport in an irrigated watershed, the model links the finite-difference models MODFLOW, UZF-RT3D, and OTIS, to simulate flow and reactive transport of multiple chemical species in both the aquifer and a stream network, with mass exchange between the two. The capability of the new model is showcased by calibration, testing, and application to a 500 km2 region in Colorado’s Lower Arkansas River Valley using a rich data set gathered over a 10-yr period. Simulation of spatial and temporal distributions of Se concentration reveals conditions that exceed standards in groundwater for approximately 20% of the area. For the Arkansas River, standards are exceeded by 290%–450%. Simulation indicates that river concentrations of NO3 alone are near the current interim standard for the total of all dissolved N species. These results indicate the need for future use of the developed model to investigate the prospects for land and water best management practices to decrease pollutant levels.

  17. Simulating selenium and nitrogen fate and transport in coupled stream-aquifer systems of irrigated regions

    Science.gov (United States)

    Shultz, Christopher D.; Bailey, Ryan T.; Gates, Timothy K.; Heesemann, Brent E.; Morway, Eric D.

    2018-05-01

    Elevated levels of selenium (Se) in aqueous environments can harm aquatic life and endanger livestock and human health. Although Se occurs naturally in the rocks and soils of many alluvial aquifers, mining and agricultural activities can increase its rate of mobilization and transport to surface waters. Attention is given here to regions where nonpoint source return flows from irrigated lands carry pollutant loads to aquifers and streams, contributing to concentrations that violate regulatory and performance standards. Of particular concern is the heightened level and mobilization of Se influenced by nitrate (NO3), a harmful pollutant in its own right. We present a numerical model that simulates the reactive transport of Se and nitrogen (N) species in a coupled groundwater-surface water system. Building upon a conceptual model that incorporates the major processes affecting Se and NO3 transport in an irrigated watershed, the model links the finite-difference models MODFLOW, UZF-RT3D, and OTIS, to simulate flow and reactive transport of multiple chemical species in both the aquifer and a stream network, with mass exchange between the two. The capability of the new model is showcased by calibration, testing, and application to a 500 km2 region in Colorado's Lower Arkansas River Valley using a rich data set gathered over a 10-yr period. Simulation of spatial and temporal distributions of Se concentration reveals conditions that exceed standards in groundwater for approximately 20% of the area. For the Arkansas River, standards are exceeded by 290%-450%. Simulation indicates that river concentrations of NO3 alone are near the current interim standard for the total of all dissolved N species. These results indicate the need for future use of the developed model to investigate the prospects for land and water best management practices to decrease pollutant levels.

  18. Using Remote Sensing Technology on the Delimitation of the Conservation Area for the Jianan Irrigation System Cultural Landsccape

    Science.gov (United States)

    Wang, C. H.

    2015-08-01

    In recent years the cultural landscape has become an important issue for cultural heritages throughout the world. It represents the "combined works of nature and of man" designated in Article 1 of the World Heritage Convention. When a landscape has a cultural heritage value, important features should be marked and mapped through the delimitation of a conservation area, which may be essential for further conservation work. However, a cultural landscape's spatial area is usually wider than the ordinary architectural type of cultural heritage, since various elements and impact factors, forming the cultural landscape's character, lie within a wide geographic area. It is argued that the conservation of a cultural landscape may be influenced by the delimitation of the conservation area, the corresponding land management measures, the limits and encouragements. The Jianan Irrigation System, an historical cultural landscape in southern Taiwan, was registered as a living cultural heritage site in 2009. However, the system's conservation should not be limited to just only the reservoir or canals, but expanded to irrigated areas where farmland may be the most relevant. Through the analysis process, only approximately 42,000 hectares was defined as a conservation area, but closely related to agricultural plantations and irrigated by the system. This is only half of the 1977 irrigated area due to urban sprawl and continuous industrial expansion.

  19. Monitoring and Evaluation of Cultivated Land Irrigation Guarantee Capability with Remote Sensing

    Science.gov (United States)

    Zhang, C., Sr.; Huang, J.; Li, L.; Wang, H.; Zhu, D.

    2015-12-01

    Abstract: Cultivated Land Quality Grade monitoring and evaluation is an important way to improve the land production capability and ensure the country food safety. Irrigation guarantee capability is one of important aspects in the cultivated land quality monitoring and evaluation. In the current cultivated land quality monitoring processing based on field survey, the irrigation rate need much human resources investment in long investigation process. This study choses Beijing-Tianjin-Hebei as study region, taking the 1 km × 1 km grid size of cultivated land unit with a winter wheat-summer maize double cropping system as study object. A new irrigation capacity evaluation index based on the ratio of the annual irrigation requirement retrieved from MODIS data and the actual quantity of irrigation was proposed. With the years of monitoring results the irrigation guarantee capability of study area was evaluated comprehensively. The change trend of the irrigation guarantee capability index (IGCI) with the agricultural drought disaster area in rural statistical yearbook of Beijing-Tianjin-Hebei area was generally consistent. The average of IGCI value, the probability of irrigation-guaranteed year and the weighted average which controlled by the irrigation demand index were used and compared in this paper. The experiment results indicate that the classification result from the present method was close to that from irrigation probability in the gradation on agriculture land quality in 2012, with overlap of 73% similar units. The method of monitoring and evaluation of cultivated land IGCI proposed in this paper has a potential in cultivated land quality level monitoring and evaluation in China. Key words: remote sensing, evapotranspiration, MODIS cultivated land quality, irrigation guarantee capability Authors: Chao Zhang, Jianxi Huang, Li Li, Hongshuo Wang, Dehai Zhu China Agricultural University zhangchaobj@gmail.com

  20. A solar energy powered autonomous wireless actuator node for irrigation systems.

    Science.gov (United States)

    Lajara, Rafael; Alberola, Jorge; Pelegrí-Sebastiá, José

    2011-01-01

    The design of a fully autonomous and wireless actuator node ("wEcoValve mote") based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The "wEcoValve mote" firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW.

  1. A Solar Energy Powered Autonomous Wireless Actuator Node for Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Rafael Lajara

    2010-12-01

    Full Text Available The design of a fully autonomous and wireless actuator node (“wEcoValve mote” based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The “wEcoValve mote” firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW.

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

    OpenAIRE

    Muhammad Afzal

    1996-01-01

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

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-01

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

  5. Water reuse and cost-benefit of pumping at different spatial levels in a rice irrigation system in UPRIIS, Philippines

    Science.gov (United States)

    Hafeez, M. M.; Bouman, B. A. M.; Van de Giesen, N.; Mushtaq, S.; Vlek, P.; Khan, S.

    As agricultural water resources in Asia become increasingly scarce, the irrigation efficiency of rice must be improved. However, in this region there is very limited information available about water use efficiency across spatial levels in irrigation systems. This study quantifies the volume of water reuse and its related cost-benefits at five different spatial levels, ranging from 1500 ha to 18,000 ha, under gravity-fed irrigation system in Upper Pumpanga River Integrated Irrigation System (UPRIIS), Philippines. The major sources of water reuse are considered, namely groundwater pumping, pumping from creeks, combined use and irrigation supplies from check dams. The volume of water available from all four sources of water reuse was quantified through extensive measurements. Production functions were developed to quantify water-yield relationships and to measure the economic value of water reuse. This study was conducted during the dry season of 2001, which existed from 19 November 2000 until 18 May 2001. The water reuse by pumping and check dams was 7% and 22% of the applied surface water at District 1 level. The reuse of surface water through check dams increased linearly with 4.6 Mm 3 per added 1000 ha. Similarly, the total amount of reused water from pumping is equivalent to 30% of the water lost through rice evapotranspiration during the dry season 2001. The results showed that water reuse plays a dominant role in growing a rice crop during the dry season. The result showed no difference in pumping costs between the creek (US0.011/m 3) and shallow pumps (US0.012/m 3). The marginal value of productivity (MVP) of water reuse from creek (US0.044/m 3) was slightly higher than the water reuse through the pumping ground water (US0.039/m 3). Results also indicated that the total volume pumped per ha (m 3/ha) was ranging from 0.39 to 6.93 m 3/ha during the dry season. The results clearly indicate that the quantification of amount of water reuse is very crucial for

  6. Analysis of energy requirement in the irrigation sector and its application in groundwater over-pumping control at a local scale - A case study in the North China Plain

    Science.gov (United States)

    Wang, L.; Kinzelbach, W.; Yao, H.; Hagmann, A.; Li, N.; Steiner, J. F.

    2017-12-01

    The North China Plain is one of the most important agricultural regions which relies heavily on groundwater pumping for irrigation powered by electric energy. This region is also facing a severe problem of groundwater over-pumping. Stopping groundwater depletion by controlling pumping for irrigation may harm the agricultural production and affect the interests of the electricity utility who is a direct participant in the irrigation management. Water-saving infrastructures such as sprinklers can be effective means for water conservation but are often difficult to implement due to farmers' unwillingness to pay for the additional electricity consumption. Understanding this food-energy-water nexus is fundamental to implement effective and practical strategies for groundwater over-pumping control in the North China Plain. However, this understanding can be obscured by the missing groundwater pumping monitoring and a lack of access to specific energy data for irrigation use as well as the field observations of pump efficiency. Taking the example of a typical agricultural county (Guantao) in the North China Plain with irrigation pumps generally powered by electricity, this study is focused on the analysis of the energy requirement in the irrigation sector and its application in developing strategies for groundwater over-pumping control at the county scale. 1) Field measurements from pumping tests are used to adjust the pumps' theoretical characteristics. A simple empirical equation is derived to estimate the energy use rate for irrigation given the depth of the groundwater table. Field measurements show that pump efficiency is around 30% in the tested region. 2) We hypothesize that the inter-annual variability of rural energy consumption is caused by the randomness in annual precipitation. This assumption is examined and then applied to separate the energy consumption for irrigation from the total rural energy consumption. 3) Based on the groundwater pumping rate

  7. Using Remote Sensing Technology on the Delimitation of the Conservation Area for the Jianan Irrigation System Cultural Landsccape

    Directory of Open Access Journals (Sweden)

    C. H. Wang

    2015-08-01

    Full Text Available In recent years the cultural landscape has become an important issue for cultural heritages throughout the world. It represents the "combined works of nature and of man" designated in Article 1 of the World Heritage Convention. When a landscape has a cultural heritage value, important features should be marked and mapped through the delimitation of a conservation area, which may be essential for further conservation work. However, a cultural landscape’s spatial area is usually wider than the ordinary architectural type of cultural heritage, since various elements and impact factors, forming the cultural landscape’s character, lie within a wide geographic area. It is argued that the conservation of a cultural landscape may be influenced by the delimitation of the conservation area, the corresponding land management measures, the limits and encouragements. The Jianan Irrigation System, an historical cultural landscape in southern Taiwan, was registered as a living cultural heritage site in 2009. However, the system’s conservation should not be limited to just only the reservoir or canals, but expanded to irrigated areas where farmland may be the most relevant. Through the analysis process, only approximately 42,000 hectares was defined as a conservation area, but closely related to agricultural plantations and irrigated by the system. This is only half of the 1977 irrigated area due to urban sprawl and continuous industrial expansion.

  8. Estimating irrigation water demand using an improved method and optimizing reservoir operation for water supply and hydropower generation: a case study of the Xinfengjiang reservoir in southern China

    Science.gov (United States)

    Wu, Yiping; Chen, Ji

    2013-01-01

    The ever-increasing demand for water due to growth of population and socioeconomic development in the past several decades has posed a worldwide threat to water supply security and to the environmental health of rivers. This study aims to derive reservoir operating rules through establishing a multi-objective optimization model for the Xinfengjiang (XFJ) reservoir in the East River Basin in southern China to minimize water supply deficit and maximize hydropower generation. Additionally, to enhance the estimation of irrigation water demand from the downstream agricultural area of the XFJ reservoir, a conventional method for calculating crop water demand is improved using hydrological model simulation results. Although the optimal reservoir operating rules are derived for the XFJ reservoir with three priority scenarios (water supply only, hydropower generation only, and equal priority), the river environmental health is set as the basic demand no matter which scenario is adopted. The results show that the new rules derived under the three scenarios can improve the reservoir operation for both water supply and hydropower generation when comparing to the historical performance. Moreover, these alternative reservoir operating policies provide the flexibility for the reservoir authority to choose the most appropriate one. Although changing the current operating rules may influence its hydropower-oriented functions, the new rules can be significant to cope with the increasingly prominent water shortage and degradation in the aquatic environment. Overall, our results and methods (improved estimation of irrigation water demand and formulation of the reservoir optimization model) can be useful for local watershed managers and valuable for other researchers worldwide.

  9. Evaluation of Fluent Software for Simulation and Costruction of a Variable Rate Sprinkler for an Autonomous Irrigation System

    Directory of Open Access Journals (Sweden)

    H Roshan

    2014-09-01

    Full Text Available Water scarcity is today’s world biggest challenge which requires different countries to manage their water resources in the most efficient way. Sprinkler irrigation increases water consumption efficiency due to more uniform distribution of water across the field. Precision farming is based on the site-specific use of inputs according to soil characteristics and plant needs. One of the main inputs for agricultural production is water. Thus, efficient use of water resources based on variable rate irrigation is considered to be a basic approach of precision irrigation. The main purpose of this study was to simulate and fabricate a variable flow sprinkler, applicable in solid set sprinkler irrigation system. The preliminary drawing of the proposed sprinkler, which equipped with a flow and pressure control plunger, was simulated using Fluent software. The actual sprinkler was then fabricated and evaluated in a field. The performance of the sprinkler was evaluated at three pressure levels, three plunger positions (at the points of the least and biggest sprinkler’s cross section for water passage and three diameters of outlet nozzle opening. Results showed that the plunger had the capability of varying outlet flow and pressure in the sprinkler and trends in flow and pressure variation as affected by the plunger position was very complicated. The Fluent model for conditions with fully open of the plunger and half opened was effectively efficient. However, as the plunger closed the water passage more than the half of cross section, the model did not show an acceptable efficiency.

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

    NARCIS (Netherlands)

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

    2017-01-01

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

  11. Use of neutron scattering meter to detect soil moisture distribution under trickle irrigation system in sandy soil of inshas, Egypt

    International Nuclear Information System (INIS)

    Abd El-moniem, M.; El-gendy, R.W.; Gadalla, A.M.; Hamdy, A.; Zeedan, A.

    2006-01-01

    This study aims to investigate the soil moisture distribution under different quantities of irrigation water in cultivated sandy soil with squash, using drip irrigation system. This study was carried out in Inshas sandy soil at the farm of Soil and Water Research Department, Nuclear Research Centre, Atomic Energy Authority, Egypt. Three rates of applied irrigation water (100, 75 and 50 % ETc) were used. Three sites (0, 12.5 and 25 cm distances from the emitter between drippers and laterals lines) were chosen to measure soil moisture contents (horizontal and vertical directions within the soil depths). The obtained data pointed out that the maximum width, in onion shape of water distribution under drip irrigation system, was at 45 cm depth at 0 site. From the study of soil moisture distribution, the overlapping between each two neighbor drippers played a good role in increasing soil moisture content at the 25 site rather than the rest sites. Water distribution was affected with plant location within the wet area as well as the used irrigation water quantities. Water distribution between drippers and laterals did not differ much approximately. The highest soil moisture depletion was at 12.5 site (between drippers) for 100 and 75 % ETc rather than the rest treatments. 100 % ETc treatment introduced the highest soil moisture depletion in the first stage of plant growth season for the three sites (between drippers and laterals). In the last stage of plant growth season, water re-distribution phenomena resulted from the changeable total hydraulic potential, which played important role for interpretation of results

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

    OpenAIRE

    Verzijl, A.; Guerrero Quispe, S.

    2013-01-01

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

  13. Endangered Species and Irrigated Agriculture, Water Resource Competition in Western River Systems

    OpenAIRE

    United States Department of Agriculture, Economic Research Service

    1995-01-01

    This report characterizes several aspects of water allocation tradeoffs between fish species listed under the Federal Endangered Species Act and agriculture in the American West. The geographic intersection between endangered/threatened (E/T) fish and agricultural production reliant on surface water for irrigation is identified. Three findings are: (1) 235 counties, representing 22 percent of the West's counties, contain irrigated production that relies on water from rivers with E/T fish, ...

  14. Relative Water Uptake as a Criterion for the Design of Trickle Irrigation Systems

    Science.gov (United States)

    Communar, G.; Friedman, S. P.

    2008-12-01

    Previously derived analytical solutions to the 2- and 3-dimensional water flow problems describing trickle irrigation are not being widely used in practice because those formulations either ignore root water uptake or refer to it as a known input. In this lecture we are going to describe a new modeling approach and demonstrate its applicability for designing the geometry of trickle irrigation systems, namely the spacing between the emitters and drip lines. The major difference between our and previous modeling approaches is that we refer to the root water uptake as to the unknown solution of the problem and not as to a known input. We postulate that the solution to the steady-state water flow problem with a root sink that is acting under constant, maximum suction defines un upper bound to the relative water uptake (water use efficiency) in actual transient situations and propose to use it as a design criterion. Following previous derivations of analytical solutions we assume that the soil hydraulic conductivity increases exponentially with its matric head, which allows the linearization of the Richards equation, formulated in terms of the Kirchhoff matric flux potential. Since the transformed problem is linear, the relative water uptake for any given configuration of point or line sources and sinks can be calculated by superposition of the Green's functions of all relevant water sources and sinks. In addition to evaluating the relative water uptake, we also derived analytical expressions for the steam functions. The stream lines separating the water uptake zone from the percolating water provide insight to the dependence of the shape and extent of the actual rooting zone on the source- sink geometry and soil properties. A minimal number of just 3 system parameters: Gardner's (1958) alfa as a soil type quantifier and the depth and diameter of the pre-assumed active root zone are sufficient to characterize the interplay between capillary and gravitational effects on

  15. Subsurface irrigation of potato crop (Solanum tuberosum ssp. Andigena) in Suka Kollus with different drainage systems

    Science.gov (United States)

    Serrano-Coronel, Genaro; Chipana-Rivera, René; Fátima Moreno-Pérez, María; Roldán-Cañas, José

    2016-04-01

    Among the most important hydraulic structures of pre-Hispanic ancestral technology developed in the Andean region, we find the suka kollus, aymara word, called also waru waru, en quechua or raised fields, in English. They are raised platforms surrounded by water canals that irrigate subsurface, but also have the function of draining, to deal with floods because they are surrounding Lake Titicaca. They also have the property of generating a thermoregulatory effect to crops, depending on the configuration of the channels and platforms. Such agro-ecosystems are being abandoned, however, if properly addressed crop management and some drainage canals are replaced by underground drains for increased crop area could be very useful in enabling marginal soils affected by salts and / or excess water. For these reasons, the objective of this study was to evaluate the subsurface irrigation in the potato crop in suka kollus under a system of surface drainage, and mixed drainage (surface and subsurface). The study was conducted in marginal soils of Kallutaca area, located 30 km from the city of La Paz, Bolivia, at a height of 3892 m.a.s.l. The cultivation of the potato (Solanum tuberosum ssp. Andigena) was used. Four treatments were tested with different widths of the platforms: T1 (Control) with drainage through channels; T2 (replacing a channel by a drain); T3 (replacing two channels by two drains); T4 (replacing three channels by three drains). The flow of water into the soil from the water table was predominantly upward, except during periods of high rainfall. In terms of treatments, the flow in T1 was higher, mainly at weeks 8 to 11 after seedling emergence, coinciding with the phenological phases of flowering and at the beginning of the tuber ripening. It was followed by T3, T2 and T4 treatments, respectively. Tuber yield, if one considers that the channels detract arable land, was higher in the T3 treatment,16.4 Mg / ha, followed by T2 treatment, 15.2 Mg / ha, T1

  16. Performance of a 10 kilowatt wind-electric water pumping system for irrigating crops

    Energy Technology Data Exchange (ETDEWEB)

    Vick, B.D.; Clark, R.N. [Conservation and Production Research Lab., Bushland, TX (United States); Molla, S. [Texas A& M Univ., College Station, TX (United States)

    1997-12-31

    A 10 kW wind-electric water pumping system was tested for field crop irrigation at pumping depths from 50 to 120 m. The wind turbine for this system used a permanent magnet alternator that powered off-the-shelf submersible motors and pumps without the use of an inverter. Pumping performance was determined at the USDA-Agricultural Research Service (ARS), Wind Energy Laboratory in Bushland, TX for the 10 kW wind turbine using a pressure valve and a pressure tank to simulate different pumping depths. Pumping performance was measured for two 10 kW wind turbines of the same type at farms near the cities of Garden City, TX and Stiles, TX. The pumping performance data collected at these actual wells compared favorably with the data collected at the USDA-ARS, Wind Energy Laboratory. If utility generated electricity was accessible, payback on the wind turbine depended on the cost of utility generated electricity and the transmission line extension cost.

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

    Science.gov (United States)

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

    2010-12-01

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

  18. Nutrition of Tithonia diversifolia and attributes of the soil fertilized with biofertilizer in irrigated system

    Directory of Open Access Journals (Sweden)

    Matheus M. Reis

    Full Text Available ABSTRACT The fertilization with biofertilizer associated with the use of irrigation favors nutrient uptake by plants and soil chemical properties; however, these effects are little studied in Tithonia diversifolia in semiarid regions. This study evaluated the effect of doses of bovine biofertilizer and irrigation on accumulation of nutrients in the leaves of Tithonia diversifolia plants and on soil chemical attributes. The study was carried out from December 3, 2014 to November 28, 2015, and arranged in a 2 x 5 factorial scheme, consisting of five doses of bovine biofertilizer (0, 40, 80, 120 and 160 m3 ha-1, combined with and without irrigation. The experiment was set in a randomized block design, using three replicates. Irrigation promoted increased accumulation of N, P, K, Ca, Mg, S, Zn, Fe, Mn, Cu and B in leaves of Tithonia diversifolia in the first cutting. However, the high bicarbonate concentration in the irrigation water and the occurrence of rainfall during the second crop increased the accumulation of Cu in the leaves of Tithonia diversifolia under rainfed condition, compared with irrigated plants. The increase in biofertilizer doses contributed to the increment of base saturation and the contents of organic matter, P and K in soil.

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

    Science.gov (United States)

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

    2017-01-01

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

  20. QUALITY IMPROVEMENT OF MANGOSTEEN FOR EXPORT THROUGH DRIP IRRIGATION SYSTEM AND YELLOW FLUORESCENT STICKY TRAP INSTALLATION

    Directory of Open Access Journals (Sweden)

    Affandi

    2011-10-01

    Full Text Available Mangosteen (Garcinia mangostana Linn. dubbed as “finest fruit of the world”, has potential for both domestic market and export. However, this potential is threatened by low fruit quality caused by production of yellow latex and fruit scarring. The research objective was to obtain technology to reduce yellow latex and control Scirtothrips dorsalis, a pest that causes scarring on mangosteen. A randomized block design with four treatments and 14 replications was used in this research. Significant differences among the treatments were calculated using the Honestly Significant Difference (HSD test. The results showed that treatment of drip irrigation system in combination with removing weeds under the canopy (A or removing weeds followed by minimum tillage under the canopy (B or removing weeds then covering with rice hay mulch under the canopy (C, where N, P, K, Ca, Mg fertilizer and yellow fluorescent sticky trap were applied could reduce scarring intensity and percentage of yellow latex on the fruit peel. However, the treatments did not significantly impact fruit diameter or percentage of yellow latex inside the fruit. Nevertheless, treatment C improved mangosteen quality by as much as 67.79% fulfilling export standard requirements.

  1. Evaluation of water distribution under pivot irrigation systems using remote sensing imagery in eastern Nile delta

    Directory of Open Access Journals (Sweden)

    E. Farg

    2017-04-01

    Full Text Available Traditional methods for center pivot evaluation depend on the water depth distribution along the pivot arm. Estimation and mapping the water depth under pivot irrigation systems using remote sensing data is essential for calculating the coefficient of uniformity (CU of water distribution. This study focuses on estimating and mapping water depth using Landsat OLI 8 satellite data integrated with Heerman and Hein (1968 modified equation for center pivot evaluation. Landsat OLI 8 image was geometrically and radiometrically corrected to calculate the vegetation and water indices (NDVI and NDWI in addition to land surface temperature. Results of the statistical analysis showed that the collected water depth in catchment cans is also highly correlated negatively with NDVI. On the other hand water, depth was positively correlated with NDWI and LST. Multi-linear regression analysis using stepwise selection method was applied to estimate and map the water depth distribution. The results showed R2 and adjusted R2 0.93 and 0.88 respectively. Study area or field level verification was applied for estimation equation with correlation 0.93 between the collected water depth and estimated values.

  2. What role can information play in improved equity in Pakistan's irrigation system? Evidence from an experimental game in Punjab

    Directory of Open Access Journals (Sweden)

    Andrew Reid. Bell

    2015-03-01

    Full Text Available The Indus Basin Irrigation System suffers significant inequity in access to surface water across its millions of users. Information, i.e., monitoring and reporting of water availability, may be of value in improving conditions across the basin, and we investigated this via an experimental game of water distribution in Punjab, Pakistan. We found evidence that flow information allowed players to take more effective action to target overuse, and that overall activities that might bring social disapproval were reduced with information. However, we did not find any overall improvement in equity across the system, suggesting that information on its own might not be sufficient to lead to better water distribution among irrigators.

  3. Economic profitability in conventional and irrigated coffee production systems in three municipalities in the Marilia region of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Helena Nogueira Turco

    2017-11-01

    Full Text Available ABSTRACT: The objective of this study was to evaluate the economic benefit of coffee cultivation, with a focus on the distinction between conventional and irrigated coffee production systems. For the development of the study, the various productive systems were delineated from the data provided by a sample of producers to generate a matrix of average technical coefficients. The methodology used to estimate the operating cost of production is the one used by the Instituto de Economia Agrícola (IEA. Profitability indicators were also evaluated. Results indicated that the effective operational cost (EOC incurred in the irrigated production system is higher than that in the conventional system. As regards the cost composition, in the conventional coffee production system, the largest cost incurred is on fertilizers among all inputs, whereas in the irrigated production system, the largest cost incurred is on machinery and equipment that are mainly used in harvesting, for the period 2013-2015. Profitability index of the conventional coffee production system in 2015 was 44.8%, and that of the drip irrigated production system was 49.7%. In 2014, profitability rates were negative for both the conventional (-13.9% and irrigated coffee production systems (-8.6%. The most preferable choice was found to be the irrigated production system, as it allows reducing the risk of loss in production during prolonged periods of water shortage as well as greater yields due to a larger production of grains.

  4. RAF/5/071: Enhancing Crop Nutrition and Soil and Water Management and Technology Transfer in Irrigated Systems for Increased Food Production and Income Generation (AFRA)

    International Nuclear Information System (INIS)

    Sijali, I.

    2017-01-01

    The overall objective is to enhance food security, income and the resilience of smallholder farmers through climate change adaptive, mitigation and coping strategies and specific objective to Improve water and nitrogen use efficiency under different irrigated cropping systems using quantifying nuclear technique. Technologies perfected at KALRO transferred to pastoral communities (Maasai land). Technologies included drip irrigation systems for vegetables and orchards, water harvesting ponds dam lining, Solar pump, greenhouse management techniques and introduction of new crops such as sweet potatoes, green grams and sorghums. A low-cost solar-powered irrigation pump has been developed by on-station testing and demonstration was done for a small solar pump

  5. An integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes.

    Science.gov (United States)

    Chiaradia, Enrico Antonio; Facchi, Arianna; Masseroni, Daniele; Ferrari, Daniele; Bischetti, Gian Battista; Gharsallah, Olfa; Cesari de Maria, Sandra; Rienzner, Michele; Naldi, Ezio; Romani, Marco; Gandolfi, Claudio

    2015-09-01

    The cultivation of rice, one of the most important staple crops worldwide, has very high water requirements. A variety of irrigation practices are applied, whose pros and cons, both in terms of water productivity and of their effects on the environment, are not completely understood yet. The continuous monitoring of irrigation and rainfall inputs, as well as of soil water dynamics, is a very important factor in the analysis of these practices. At the same time, however, it represents a challenging and costly task because of the complexity of the processes involved, of the difference in nature and magnitude of the driving variables and of the high variety of field conditions. In this paper, we present the prototype of an integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes. The system consists of the following: (1) flow measurement devices for the monitoring of irrigation supply and tailwater drainage; (2) piezometers for groundwater level monitoring; (3) level gauges for monitoring the flooding depth; (4) multilevel tensiometers and moisture sensor clusters to monitor soil water status; (5) eddy covariance station for the estimation of evapotranspiration fluxes and (6) wireless transmission devices and software interface for data transfer, storage and control from remote computer. The system is modular and it is replicable in different field conditions. It was successfully applied over a 2-year period in three experimental plots in Northern Italy, each one with a different water management strategy. In the paper, we present information concerning the different instruments selected, their interconnections and their integration in a common remote control scheme. We also provide considerations and figures on the material and labour costs of the installation and management of the system.

  6. The implementation of biofiltration systems, rainwater tanks and urban irrigation in a single-layer urban canopy model

    Science.gov (United States)

    Demuzere, Matthias; Coutts, Andrew; Goehler, Maren; Broadbent, Ashley; Wouters, Hendrik; van Lipzig, Nicole; Gebert, Luke

    2015-04-01

    Urban vegetation is generally considered as a key tool to modify the urban energy balance through enhanced evapotranspiration (ET). Given that vegetation is most effective when it is healthy, stormwater harvesting and retention strategies (such as water sensitive urban design) could be used to support vegetation and promote ET. This study presents the implementation of a vegetated lined bio-filtration system (BFS) combined with a rainwater tank (RWT) and urban irrigation system in the single-layer urban canopy model Community Land Model-Urban. Runoff from roof and impervious road surface fractions is harvested and used to support an adequate soil moisture level for vegetation in the BFS. In a first stage, modelled soil moisture dynamics are evaluated and found reliable compared to observed soil moisture levels from biofiltration pits in Smith Street, Melbourne (Australia). Secondly, the impact of BFS, RWT and urban irrigation on ET is illustrated for a two-month period in 2012 using varying characteristics for all components. Results indicate that (i) a large amount of stormwater is potentially available for indoor and outdoor water demands, including irrigation of urban vegetation, (ii) ET from the BFS is an order of magnitude larger compared to the contributions from the impervious surfaces, even though the former only covers 10% of the surface fraction and (iii) attention should be paid to the cover fraction and soil texture of the BFS, size of the RWT and the surface fractions contributing to the collection of water in the RWT. Overall, this study reveals that this model development can effectuate future research with state-of-the-art urban climate models to further explore the benefits of vegetated biofiltration systems as a water sensitive urban design tool optimised with an urban irrigation system to maintain healthy vegetation.

  7. Effect of water irrigation volume on Capsicum frutescens growth and plankton abundance in aquaponics system

    Science.gov (United States)

    Andriani, Y.; Dhahiyat, Y.; Zahidah; Subhan, U.; Iskandar; Zidni, I.; Mawardiani, T.

    2018-03-01

    This study aimed to understand Capsicum frutescens growth and plankton abundance in aquaponics culture. A Completely Randomized Design (CRD) with six treatments in triplicates comprising of treatment A (positive control using organic liquid fertilizer), B (negative control without fertilizer), C (drip irrigation aquaponics with a water debit of 100 ml/day/plant), D (drip irrigation aquaponics with a water debit of 150 ml/day/plant), E (drip irrigation with a water debit of 200 ml/day/plant), and F (drip irrigation aquaponics with a water debit of 250 ml/day/plant) was applied. The water used in treatments C, D, E, and F contained comet fish feces as fertilizer. C. frutescens growth and plankton abundance were observed. Analysis was conducted using analysis of variance for plant productivity and descriptive analysis for plankton abundance and water quality. The results of this study showed that the highest plant growth was seen in plants receiving F treatment with 50 ml/day drip irrigation. However, no significant difference was found when compared to the positive control with organic artificial fertilizer. Eleven types of phytoplankton and six types of zooplankton were found, with Stanieria sp. as the most abundant phytoplankton and Brachionus sp. and Epistylis sp. as the most abundant zooplanktons.

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

    Directory of Open Access Journals (Sweden)

    Thomas Koellner

    2012-12-01

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

  9. A rapid appraisal process on an irrigation system in Pakistan; Evaluacion rapida de una zona de riego tipica de Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Carmona, Victor Manuel; Ojeda-Bustamante, Waldo [Instituto Mexicano de Tecnologia del Agua, Jiutepec, Morelos (Mexico); Contijoch, Manuel [Banco Mundial (Mexico)

    2006-07-15

    This paper presents the results obtained on the implementation of a rapid appraisal process on an irrigation system in the province of Punjab in Pakistan. The purpose of the evaluation was to know the present irrigation service quality and to propose some alternative to improve it. The evaluation results were: the canal inflow is smaller than peak crop water requirement; net aquifer loss; crops are always under stress which is reflected on low crop yields, the secondary canal network has not control structures and was not designed for rotation, insufficient human-human communication between canal operators; the operators have no complementary training course to enhance their capacity; discrepancy between the service the canal is supposed to provide and the real service it offers. The suggested actions to improve the irrigation service were: the irrigation service must be client oriented; the irrigation users should participate to determine the irrigation service characteristics; the difference between actual and stage irrigation service must be eliminated; clear definition on water allocation; implement a modernization program to provide the irrigation service required. The evaluation methodology used can be applied in other countries like Mexico for the analysis of large irrigation systems making an optimal use of time and resources. [Spanish] En el presente trabajo se muestran los resultados obtenidos al aplicar una metodologia de evaluacion rapida de sistemas de riego a una zona de la provincia del Punjab, Pakistan. El objetivo de la evaluacion fue conocer el estado actual del servicio de riego que ofrece la agencia responsable del manejo del riego en un distrito del Punjab y proponer alternativas para mejorarlo. Los principales resultados de esta evaluacion fueron los siguientes: la falta de capacidad de los canales, el abatimiento neto del acuifero; el estres hidrico continuo de los cultivos, que propicia un bajo rendimiento; la red secundaria de canales no

  10. Design of an automatic sprinkler irrigation system for the Welsh onion growing, in La Puerta farm (Tota-Boyacá

    Directory of Open Access Journals (Sweden)

    Jorge Armando Pinto-Medina

    2012-12-01

    Full Text Available This paper presents the design for automating sprinkler irrigation system in a Welsh onion growing, which poses the required parameters, establishes the differences, advantages and results related to the traditional irrigation system used in this region (Tota, Boyacá. Starting from the resources owned by the farming unit, calculations of water requests of the plant, taking into account the crop evapotranspiration, the irrigation planning with certain factors on the basis of effective storage of soils. Two different technologies for the design are presented: hard-wired and programmable logic. The hard-wired logic system is developed as an automatic cyclical sequence with four work timed stages; on the other hand, the programmable logic controller PLC used, is the Easy-512-DC of Moller, which is provided with eight digital inputs and four relay outputs, programmed in Ladder according to the sequence of the process.

  11. Sustainable automotive energy system in China

    CERN Document Server

    CAERC, Tsinghua University

    2014-01-01

    This book identifies and addresses key issues of automotive energy in China. It covers demography, economics, technology and policy, providing a broad perspective to aid in the planning of sustainable road transport in China.

  12. Field-Based Estimates of Global Warming Potential in Bioenergy Systems of Hawaii: Crop Choice and Deficit Irrigation.

    Directory of Open Access Journals (Sweden)

    Meghan N Pawlowski

    Full Text Available Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2, as methane was oxidized and nitrous oxide (N2O emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.

  13. Field-Based Estimates of Global Warming Potential in Bioenergy Systems of Hawaii: Crop Choice and Deficit Irrigation.

    Science.gov (United States)

    Pawlowski, Meghan N; Crow, Susan E; Meki, Manyowa N; Kiniry, James R; Taylor, Andrew D; Ogoshi, Richard; Youkhana, Adel; Nakahata, Mae

    2017-01-01

    Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.

  14. Biochar amendment reduces paddy soil nitrogen leaching but increases net global warming potential in Ningxia irrigation, China.

    Science.gov (United States)

    Wang, Yongsheng; Liu, Yansui; Liu, Ruliang; Zhang, Aiping; Yang, Shiqi; Liu, Hongyuan; Zhou, Yang; Yang, Zhengli

    2017-05-09

    The efficacy of biochar as an environmentally friendly agent for non-point source and climate change mitigation remains uncertain. Our goal was to test the impact of biochar amendment on paddy rice nitrogen (N) uptake, soil N leaching, and soil CH 4 and N 2 O fluxes in northwest China. Biochar was applied at four rates (0, 4.5, 9 and13.5 t ha -1 yr -1 ). Biochar amendment significantly increased rice N uptake, soil total N concentration and the abundance of soil ammonia-oxidizing archaea (AOA), but it significantly reduced the soil NO 3 - -N concentration and soil bulk density. Biochar significantly reduced NO 3 - -N and NH 4 + -N leaching. The C2 and C3 treatments significantly increased the soil CH 4 flux and reduced the soil N 2 O flux, leading to significantly increased net global warming potential (GWP). Soil NO 3 - -N rather than NH 4 + -N was the key integrator of the soil CH 4 and N 2 O fluxes. Our results indicate that a shift in abundance of the AOA community and increased rice N uptake are closely linked to the reduced soil NO 3 - -N concentration under biochar amendment. Furthermore, soil NO 3 - -N availability plays an important role in regulating soil inorganic N leaching and net GWP in rice paddies in northwest China.

  15. Carbon retention in the soil–plant system under different irrigation regimes

    DEFF Research Database (Denmark)

    Wang, Yaosheng; Liu, Fulai; Andersen, Mathias Neumann

    2010-01-01

    their environmental impacts. Tomato plants (Lycopersicon esculentum L., var. Cedrico) were grown in split-root pots in a climate-controlled glasshouse and were subjected to full irrigation (FI), deficit irrigation (DI) and alternate partial root-zone irrigation (PRI) at early fruiting stage. In Exp. I, each plant...... to a greater microbial activity in the two treatments; particularly the PRI induced drying and wetting cycles of the soils may cause an increase of microbial activities and respiration rate, which could lead to more C losses from the soil. However, in both experiments the total C concentration in the PRI...... in the two experiments might have affected the C retention in the soil and in the plant biomass. Nevertheless, with a same degree of water saving, PRI was superior to DI in terms of enhancing C concentration in the plant biomass, which might have contributed to a better fruit quality in tomatoes as reported...

  16. Simulating Water Allocation and Cropping Decisions in Yemen’s Abyan Delta Spate Irrigation System

    Directory of Open Access Journals (Sweden)

    Derek Jin-Uk Marchant

    2018-01-01

    Full Text Available Agriculture employs more Yemenis than any other sector and spate irrigation is the largest source of irrigation water. Spate irrigation however is growing increasingly difficult to sustain in many areas due to water scarcity and unclear sharing of water amongst users. In some areas of Yemen, there are no institutionalised water allocation rules which can lead to water related disputes. Here, we propose a proof-of-concept model to evaluate the impacts of different water allocation patterns to assist in devising allocation rules. The integrated model links simple wadi flow, diversion, and soil moisture-yield simulators to a crop decision model to evaluate impacts of different water allocation rules and their possible implications on local agriculture using preliminary literature data. The crop choice model is an agricultural production model of irrigation command areas where the timing, irrigated area and crop mix is decided each month based on current conditions and expected allocations. The model is applied to Yemen’s Abyan Delta, which has the potential to be the most agriculturally productive region in the country. The water allocation scenarios analysed include upstream priority, downstream priority, equal priority (equal sharing of water shortages, and a user-defined mixed priority that gives precedence to different locations based on the season. Once water is distributed according to one of these allocation patterns, the model determines the profit-maximising plant date and crop selection for 18 irrigated command areas. This aims to estimate the impacts different water allocation strategies could have on livelihoods. Initial results show an equal priority allocation is the most equitable and efficient, with 8% more net benefits than an upstream scenario, 10% more net benefits than a downstream scenario, and 25% more net benefits than a mixed priority.

  17. Identification of Decisive Factors Determining the Continued Use of Rainwater Harvesting Systems for Agriculture Irrigation in Beijing

    Directory of Open Access Journals (Sweden)

    Xiao Liang

    2015-12-01

    Full Text Available The success or failure of operating a rainwater harvesting system (RWH depends on both technological and non-technological factors. The importance of non-technological factors in attaining sustainable RWH operation is rarely emphasized. This study aims to assess the contribution of non-technological factors through determining decisive factors involved in the use of RWHs for agriculture irrigation in Beijing. The RWHs for agriculture irrigation in Beijing are not operating as well as expected. If the decisive factors are identified to be non-technological, the significance of non-technological factors will be highlighted. Firstly, 10 impact factors comprising non-technological and technological factors are selected according to both a literature review and interviews with RWH managers. Following this, through an artificial data mining method, rough set analysis, the decisive factors are identified. Results show that two non-technological factors, “doubts about rainwater quality” and “the availability of groundwater” determine whether these systems will continue or cease RWH operation in Beijing. It is, thus, considered necessary to improve public confidence in and motivation on using rainwater for agriculture irrigation, as this is the main obstacle in the sustainable and successful operation of RWHs. Through a case study of RWHs in Beijing, the study verifies the importance of acknowledging non-technological factors to achieve sustainable water management and considers that such factors should receive more attention by decision makers and researchers.

  18. Influence of genotype, cultivation system and irrigation regime on antioxidant capacity and selected phenolics of blueberries (Vaccinium corymbosum L.).

    Science.gov (United States)

    Cardeñosa, Vanessa; Girones-Vilaplana, Amadeo; Muriel, José Luis; Moreno, Diego A; Moreno-Rojas, José M

    2016-07-01

    Demand for and availability of blueberries has increased substantially over recent years, driven in part by their health-promoting properties. Three blueberry varieties ('Rocío', V2, and V3) were grown under two cultivation systems (open-field and plastic tunnels) and subjected to two irrigations regimes (100% and 80% of crop evapotranspiration) in two consecutive years (2011-2012). They were evaluated for their phytochemical composition and antioxidant capacity. Genotype influenced the antioxidant capacity and the content of the three groups of phenolics in the blueberries. The antioxidant activity and total flavonols content increased when the blueberries were grown under open-field conditions. Deficit irrigation conditions led to additional positive effects on their phenolics (delphinidn-3-acetilhexoside content was increased under plastic tunnel with deficit irrigation). In conclusion, the amount of phenolic compounds and the antioxidant capacity of blueberries were not negatively affected by water restriction; Moreover, several changes were recorded due to growing system and genotype. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Learning from the Field : Innovating China's Higher Education System

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

    2008-04-15

    Learning from the Field : Innovating China's Higher Education System. Couverture du livre Learning from the Field : Innovating China's Higher Education System. Editor(s):. Ronnie Vernooy, Li Xiaoyun, Xu Xiuli, Lu Min, et Qi Gubo. Publisher(s):. Foundation Book, CRDI. April 15, 2008. ISBN: 9788175966017. 260 pages.

  20. Monitoring and risk assessment of pesticides in irrigation systems in Debra Zeit, Ethiopia.

    Science.gov (United States)

    Teklu, Berhan M; Adriaanse, Paulien I; Van den Brink, Paul J

    2016-10-01

    Since Ethiopia is going through a rapid transformation of its agricultural sector, we assessed the human health and environmental risks due to the past use of organochlorine pesticides (OCPs) as well as the risks of the current pesticide use by farmers. A monitoring programme and risk assessment was carried out for the Wedecha-Belbela irrigation system in the Debra Zeit area. The Wedecha and Belbela rivers and adjacent temporary ponds were sampled and examined for the presence of OCPs between August and October 2014, while data on the current pesticide use by small- and large-scale farmers was collected by interviews. The usage patterns were evaluated for risks of using the river or temporary ponds as source of drinking water and for risks for the aquatic ecosystems in the river and ponds with the aid of the PRIMET_Registration_Ethiopa_1.1 model. The samples were collected in five sampling periods, and results indicate that most of the 18 target OCPs were not detected above the detection limit, while g-chlordane may pose chronic risks when surface water is used as drinking water. Endosulfan and heptachlor pose risks to aquatic organisms at second-tier level, while for heptachlor-epoxide B, g-chlordane and b-BHC only risks could be determined at the first tier due to a lack of data. For all nine pesticides used by small-scale farmers the calculated acute risks to humans were low. Second tier risk assessment for the aquatic ecosystem indicated that lambda-cyhalothrin, endosulfan, profenofos, and diazinon may pose high risks. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

  2. Review of the water management systems in the Gujarat Medium Irrigation II Project (Credit 1496-IN)

    NARCIS (Netherlands)

    Brouwer, R.

    1993-01-01

    Different activities are ongoing in the Medium Irrigation II project simultaneously. These are: - emancipation of farmers through their involvement in the operation and management; - change over from Sheshpali type water management to RWS type water management; - design and construction of remaining

  3. Management systems in irrigated rice affect physical and chemical soil properties

    NARCIS (Netherlands)

    Rodrigues de Lima, A.C.; Hoogmoed, W.B.; Pauletto, E.A.; Pinto, L.F.S.

    2009-01-01

    Lowland soils are commonly found in the state of Rio Grande do Sul, Southern of Brazil, where they represent around 20% of the total area. Deficient drainage is the most important natural characteristic of these soils which therefore are mainly in use for irrigated rice (Oriza sativa). Degradation

  4. A Matter of Relationships : Actor-Networks of Colonial Rule in the Gezira Irrigation System, Sudan

    NARCIS (Netherlands)

    Ertsen, M.W.

    2016-01-01

    In the first half of the 20th century, colonial rulers, a British firm and Sudanese farmers changed the Gezira Plain in Sudan into a large-scale irrigated cotton scheme. Gezira continues to be in use up to date. Its story shows how the abstract concept 'development' is shaped through the agency of

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

    NARCIS (Netherlands)

    Verzijl, A.; Guerrero Quispe, S.

    2013-01-01

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

  6. THE PLACE OF CHINA IN INTERNATIONAL TRADE AND FINANCE SYSTEM

    OpenAIRE

    Kaya, Mustafa

    2015-01-01

    China, one of the oldest states of world history, adopted the open economy in 1978 and, thus, proceeded from an economy, characterized with autocracy and centralized planning, to an economy, open to international trade and foreign capital. In integration of China to the global trade system, its being a member of World Trade organization in 2001 played important role. As a result of all these developments, and the continuous and effective reforms it applied, China, nowadays, is pointed out as ...

  7. Brackish groundwater membrane system design for sustainable irrigation: Optimal configuration selection using analytic hierarchy process and multi-dimension scaling

    Directory of Open Access Journals (Sweden)

    Beni eLew

    2014-12-01

    Full Text Available The recent high demands for reuse of salty water for irrigation affected membrane producers to assess new potential technologies for undesirable physical, chemical and biological contaminants removal. This paper studies the assembly options by the analytic hierarchy process (AHP model and the multi-dimension scaling (MDS techniques. A specialized form of MDS (CoPlot software enables presentation of the AHP outcomes in a two dimensional space and the optimal model can be visualized clearly. Four types of 8 membranes were selected: (i Nanofiltration low rejection and high flux (ESNA1-LF-LD, 86% rejection, 10,500gpd; (ii Nanofiltration medium rejection and medium flux (ESNA1-LF2-LD, 91% rejection, 8,200gpd; (iii Reverse Osmosis high rejection and high flux (CPA5-MAX, 99.7 rejection, 12,000gpd ; and (iv Reverse Osmosis medium rejection and extreme high flux (ESPA4-MAX, 99.2 rejection, 13,200gpd. The results indicate that: (i Nanofiltration membrane (High flux and Low rejection can produce water for irrigation with valuable levels of nutrient ions and a reduction in the sodium absorption ratio (SAR, minimizing soil salinity; this is an attractive option for agricultural irrigation and is the optimal solution; and (ii implementing the MDS approach with reference to the variables is consequently useful to characterize membrane system design.

  8. Water production for irrigation and drinking needs in remote arid communities using closed-system greenhouse: A review

    Directory of Open Access Journals (Sweden)

    A.E. Kabeel

    2015-06-01

    Full Text Available Water needs for agriculture, food production and drinking are considered one of the most critical challenges facing the world in the present days. This is due mainly to the scarcity and lack of fresh water resources, and the increasing ground water salinity. Most of these countries have a high solar energy potential. This potential can be best developed by solar desalination concepts and methods specifically suited for rural water supply, irrigation. In this paper, a humidification–dehumidification (HD water desalination system with several technologies for irrigation and drinking needs in remote arid areas is introduced from technical and economic point of views. This study has investigated (1 detailed discussion of technical developments, economical and sustainable aspects; (2 benefits of the new design over traditional applications, desalination and other irrigation methods; (3 specific requirements and implementation challenges in remote and cold regions; (4 performance and reliability improvement possible techniques. Recommended researches and projects leading to high efficiency, economical and sustainable applications of some desalination devices driven by solar energy are highlighted.

  9. Appraising options to reduce shallow groundwater tables and enhance flow conditions over regional scales in an irrigated alluvial aquifer system

    Science.gov (United States)

    Morway, Eric D.; Gates, Timothy K.; Niswonger, Richard G.

    2013-01-01

    Some of the world’s key agricultural production systems face big challenges to both water quantity and quality due to shallow groundwater that results from long-term intensive irrigation, namely waterlogging and salinity, water losses, and environmental problems. This paper focuses on water quantity issues, presenting finite-difference groundwater models developed to describe shallow water table levels, non-beneficial groundwater consumptive use, and return flows to streams across two regions within an irrigated alluvial river valley in southeastern Colorado, USA. The models are calibrated and applied to simulate current baseline conditions in the alluvial aquifer system and to examine actions for potentially improving these conditions. The models provide a detailed description of regional-scale subsurface unsaturated and saturated flow processes, thereby enabling detailed spatiotemporal description of groundwater levels, recharge to infiltration ratios, partitioning of ET originating from the unsaturated and saturated zones, and groundwater flows, among other variables. Hybrid automated and manual calibration of the models is achieved using extensive observations of groundwater hydraulic head, groundwater return flow to streams, aquifer stratigraphy, canal seepage, total evapotranspiration, the portion of evapotranspiration supplied by upflux from the shallow water table, and irrigation flows. Baseline results from the two regional-scale models are compared to model predictions under variations of four alternative management schemes: (1) reduced seepage from earthen canals, (2) reduced irrigation applications, (3) rotational lease fallowing (irrigation water leased to municipalities, resulting in temporary dry-up of fields), and (4) combinations of these. The potential for increasing the average water table depth by up to 1.1 and 0.7 m in the two respective modeled regions, thereby reducing the threat of waterlogging and lowering non-beneficial consumptive use

  10. Water movement and solute transport in deep vadose zone under four irrigated agricultural land-use types in the North China Plain

    Science.gov (United States)

    Min, Leilei; Shen, Yanjun; Pei, Hongwei; Wang, Ping

    2018-04-01

    Groundwater-fed agriculture has caused water table declines and groundwater quality degradation in the North China Plain. Based on sediment sampling in deep vadose zone (with a maximum depth of 11.0 m), groundwater recharge, seepage velocity, solute inventory and transport under four typical irrigated agricultural land-use types (winter wheat and summer maize, WM; pear orchards, PO; outdoor vegetables, VE; and cotton, CO) were investigated in this study. The results reveal that there are many solutes stored in the vadose zone. Nitrate storage per unit depth in the vadose zone is highest under PO (1703 kg/ha), followed by VE (970 kg/ha), WM (736 kg/ha) and CO (727 kg/ha). However, the amount of annual leached nitrate under the four land-use types results in a different order (VE, 404 kg/ha; WM, 108 kg/ha; PO, 23 kg/ha; CO, 13 kg/ha). The estimated average recharge rates are 180 mm/yr for WM, 27 mm/yr for CO, 320 mm/yr for VE and 49 mm/yr for PO. The seepage velocity under VE (2.22 m/yr) exceeds the values under the other three land-use types (WM, 0.85 m/yr; PO, 0.49 m/yr; CO, 0.09 m/yr). The highest seepage velocity under VE caused significant nitrate contamination in groundwater, whereas the other two land-use types (WM and PO) had no direct influence on groundwater quality. The results of this work could be used for groundwater resources management.

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

    Directory of Open Access Journals (Sweden)

    Qing-Han Gao

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

  12. The Influential Role of Sociocultural Feedbacks on Community-Managed Irrigation System Behaviors During Times of Water Stress

    Science.gov (United States)

    Gunda, T.; Turner, B. L.; Tidwell, V. C.

    2018-04-01

    Sociohydrological studies use interdisciplinary approaches to explore the complex interactions between physical and social water systems and increase our understanding of emergent and paradoxical system behaviors. The dynamics of community values and social cohesion, however, have received little attention in modeling studies due to quantification challenges. Social structures associated with community-managed irrigation systems around the world, in particular, reflect these communities' experiences with a multitude of natural and social shocks. Using the Valdez acequia (a communally-managed irrigation community in northern New Mexico) as a simulation case study, we evaluate the impact of that community's social structure in governing its responses to water availability stresses posed by climate change. Specifically, a system dynamics model (developed using insights from community stakeholders and multiple disciplines that captures biophysical, socioeconomic, and sociocultural dynamics of acequia systems) was used to generate counterfactual trajectories to explore how the community would behave with streamflow conditions expected under climate change. We found that earlier peak flows, combined with adaptive measures of shifting crop selection, allowed for greater production of higher value crops and fewer people leaving the acequia. The economic benefits were lost, however, if downstream water pressures increased. Even with significant reductions in agricultural profitability, feedbacks associated with community cohesion buffered the community's population and land parcel sizes from more detrimental impacts, indicating the community's resilience under natural and social stresses. Continued exploration of social structures is warranted to better understand these systems' responses to stress and identify possible leverage points for strengthening community resilience.

  13. Intercropping competition between apple trees and crops in agroforestry systems on the Loess Plateau of China.

    Science.gov (United States)

    Gao, Lubo; Xu, Huasen; Bi, Huaxing; Xi, Weimin; Bao, Biao; Wang, Xiaoyan; Bi, Chao; Chang, Yifang

    2013-01-01

    Agroforestry has been widely practiced in the Loess Plateau region of China because of its prominent effects in reducing soil and water losses, improving land-use efficiency and increasing economic returns. However, the agroforestry practices may lead to competition between crops and trees for underground soil moisture and nutrients, and the trees on the canopy layer may also lead to shortage of light for crops. In order to minimize interspecific competition and maximize the benefits of tree-based intercropping systems, we studied photosynthesis, growth and yield of soybean (Glycine max L. Merr.) and peanut (Arachis hypogaea L.) by measuring photosynthetically active radiation, net photosynthetic rate, soil moisture and soil nutrients in a plantation of apple (Malus pumila M.) at a spacing of 4 m × 5 m on the Loess Plateau of China. The results showed that for both intercropping systems in the study region, soil moisture was the primary factor affecting the crop yields followed by light. Deficiency of the soil nutrients also had a significant impact on crop yields. Compared with soybean, peanut was more suitable for intercropping with apple trees to obtain economic benefits in the region. We concluded that apple-soybean and apple-peanut intercropping systems can be practical and beneficial in the region. However, the distance between crops and tree rows should be adjusted to minimize interspecies competition. Agronomic measures such as regular canopy pruning, root barriers, additional irrigation and fertilization also should be applied in the intercropping systems.

  14. Water-right and water-allocation procedures of farmers' managed perennial spate irrigation systems of mithawan watershed, D.G. Khan, Pakistan

    International Nuclear Information System (INIS)

    Ahmad, M.; Ahmad, S.

    2007-01-01

    A study was conducted on water rights, water allocation and local institutions prevailing in the perennial spate irrigation systems of Mithawan watershed o D.G. Khan District of Punjab. The Study Area was selected is the Mthawan watershed on the D.G. Khan-Quetta Road almost 70 kms from D.G. Khan and 10 km away from the road, representing real-life operating systems. Small-scale isolated and large-scale contiguous perennial spate irrigation systems were selected for study. A three-prong methodology was designed covering (a) interactive dialogue of the focus groups to document the community-perceptions regarding systems water-rights, water allocation and local institution prevailing in the area; (b) structured interviews to document systematic data regarding some of the study-aspects; and (c) diagnostic surveys to document some of the measured data regarding scheme performance. Water rights and allocation procedures both in small-scale isolated and large-scale Contiguous perennial spate irrigation-system are very clearly defined and do not change with time and space. Local institutions like Biradri and Muchi take care of just allocation of water. An irrigator is deputed who takes care of allocated time among various tribes. At the same time, the community is bringing more area under irrigation. Obviously it has increased water-requirements and in turn management of irrigation system. Previously they were reconstructing the diversion structure only. Present expansion in irrigated area has increased the necessity of maintaining the water-conveyance network more frequently, particularly at critical sections. However, the realization regarding water-losses still needs to be promoted. The linkages of resource-management with water-productivity are going to be the future area of consideration in theses systems, due to expansion of the system largely because of increased population and urge to increase their livelihood. (author)

  15. Development of nuclear power standards and relevant system in China

    International Nuclear Information System (INIS)

    Cao Shudong

    2008-01-01

    By analyzing the history of nuclear power development and the status of nuclear power codes and standards in China, the significance and necessity to quicken the development of nuclear power standards system in China are pointed out, and the guiding ideology, development thoughts, working doctrine and development objectives are put forward in this paper. (authors)

  16. The improvement of the quality of polluted irrigation water through a phytoremediation process in a hydroponic batch culture system

    Science.gov (United States)

    Retnaningdyah, Catur

    2017-11-01

    The objective of this research was to determine the effectiveness of a phytoremediation process using some local hydro macrophytes to reduce fertilizer residue in irrigation water in order to support healthy agriculture and to prevent eutrophication and algae bloom in water. A phytoremediation process was carried out in a hydroponic floating system by using transparent plastic bags of 1 m in diameter and 1 m in height that were placed in collecting ponds before they were used for agricultural activities. Paddy soils were used as substrates in this system. The irrigation water was treated with nutrient enrichment (Urea and SP-36 fertilizers). Then, the system was planted with remediation actors (Azolla sp., Ipomoea aquatica, Limnocharis flava, Marsilea crenata, polyculture of those hydro macrophytes and control). The improvement of the water quality as a result of the phytoremediation process was characterized by a decline in the concentration of some physicochemical parameters, which were measured at 7 days after incubation, as well as an increase in the plankton diversity index value. The results showed that all of the hydro macrophytes used in this research, which was grown in the hydroponic batch culture system for a period of 7 days, were able to significantly improve the irrigation water quality, which was enriched by the synthetic fertilizers Urea and SP36. This was reflected by a significant decrease in the concentration of water TSS, nitrate, BOD, COD and total phosphate and an increase in the value of water DO at 7 days after incubation. Improvement of the water quality is also reflected in the increasing plankton diversity index value as a bioindicator of water pollution indicating a change in the pollution status from moderately polluted to slightly polluted at 7 days after incubation.

  17. China’s Water-Saving Irrigation Management System: Policy, Implementation, and Challenge

    Directory of Open Access Journals (Sweden)

    Liuyang Yao

    2017-12-01

    Full Text Available In response to the increased competition for water, the Chinese government has determined to promote water-saving irrigation (WSI followed by a range of institutional arrangements and policy goals. Three management mechanisms are analyzed in this study in terms of effectiveness, including the top-down regulation mechanism using direct control or economic instruments, the design-bid funding mechanism mobilizing local governments by competitive grants program, and the bottom-up participation mechanism transferring more irrigation management responsibilities to end-users. Although the WSI management has achieved notable improvements by the combination of different mechanisms, conflicts among different policy goals, uneven distribution of financial resources, and insufficient participation from water users caused the difficulty in aligning stakeholders’ incentives. Approaches are needed to enable sustainable management by coordinating incentives from different stakeholders in the management, as well as incorporating end water users to assist decision-making.

  18. Simulation-Optimization of the Management of Sensor-Based Deficit Irrigation Systems

    OpenAIRE

    Kloß, Sebastian

    2016-01-01

    Current research concentrates on ways to investigate and improve water productivity (WP), as agriculture is today’s predominant freshwater consumer, averaging at 70% and reaching up to 93% in some regions. A growing world population will require more food and thus more water for cultivation. Regions that are already affected by physical water scarcity and which depend on irrigation for growing crops will face even greater challenges regarding their water supply. Other problems in such regions...

  19. Breeding for high production of leaves of baobab (Adansonia digitata L) in an irrigated hedge system

    DEFF Research Database (Denmark)

    Korbo, Adama; Kjær, Erik Dahl; Sanou, Haby

    2013-01-01

    evaluated monthly from the third month after establishment. We found lowered leaf productivity during the dry season despite the plants being irrigated. We provide the first estimates of heritability for leaf production and growth of the species. We assumed that the families of seed from open...... was not significantly different among provenances or families within provenances. Based on the findings, we discuss how breeding can increase the total leaf production and its seasonal distribution....

  20. Are There Infinite Irrigation Trees?

    Science.gov (United States)

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

    2006-08-01

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

  1. The China Motor Systems Energy Conservation Program: A major national initiative to reduce motor system energy use in China

    Energy Technology Data Exchange (ETDEWEB)

    Nadel, Steven; Wang, Wanxing; Liu, Peter; McKane, Aimee T.

    2001-05-31

    Electric motor systems are widely used in China to power fans, pumps, blowers, air compressors, refrigeration compressors, conveyers, machinery, and many other types of equipment. Overall, electric motor systems consume more than 600 billion kWh annually, accounting for more than 50 percent of China's electricity use. There are large opportunities to improve the efficiency of motor systems. Electric motors in China are approximately 2-4 percent less efficient on average than motors in the U.S. and Canada. Fans and pumps in China are approximately 3-5 percent less efficient than in developed countries. Even more importantly, motors, fans, pumps, air compressors and other motor-driven equipment are frequently applied with little attention to system efficiency. More optimized design, including appropriate sizing and use of speed control strategies, can reduce energy use by 20 percent or more in many applications. Unfortunately, few Chinese enterprises use or even know about these energy-saving practices. Opportunities for motor system improvements are probably greater in China than in the U.S. In order to begin capturing these savings, China is establishing a China Motor Systems Energy Conservation Program. Elements of this program include work to develop minimum efficiency standards for motors, a voluntary ''green motor'' labeling program for high-efficiency motors, efforts to develop and promote motor system management guidelines, and a training, technical assistance and financing program to promote optimization of key motor systems.

  2. Strengthening health system to improve immunization for migrants in China.

    Science.gov (United States)

    Fang, Hai; Yang, Li; Zhang, Huyang; Li, Chenyang; Wen, Liankui; Sun, Li; Hanson, Kara; Meng, Qingyue

    2017-07-01

    Immunization is the most cost-effective method to prevent and control vaccine-preventable diseases. Migrant population in China has been rising rapidly, and their immunization status is poor. China has tried various strategies to strengthen its health system, which has significantly improved immunization for migrants. This study applied a qualitative retrospective review method aiming to collect, analyze and synthesize health system strengthening experiences and practices about improving immunizations for migrants in China. A conceptual framework of Theory of Change was used to extract the searched literatures. 11 searched literatures and 4 national laws and policies related to immunizations for migrant children were carefully studied. China mainly employed 3 health system strengthening strategies to significantly improve immunization for migrant population: stop charging immunization fees or immunization insurance, manage immunization certificates well, and pay extra attentions on immunization for special children including migrant children. These health system strengthening strategies were very effective, and searched literatures show that up-to-date and age-appropriate immunization rates were significantly improved for migrant children. Economic development led to higher migrant population in China, but immunization for migrants, particularly migrant children, were poor. Fortunately various health system strengthening strategies were employed to improve immunization for migrants in China and they were rather successful. The experiences and lessons of immunization for migrant population in China might be helpful for other developing countries with a large number of migrant population.

  3. Assessing the performance of surface and subsurface drip systems on irrigation water use efficiency of citrus orchards in Spain

    Science.gov (United States)

    Amparo Martinez-Gimeno, Maria; Provenzano, Giuseppe; Bonet, Luis; Intrigliolo, Diego S.; Badal, Eduardo; Ballestrer, Carlos

    2017-04-01

    In Mediterranean countries, water scarcity represents a real environmental concern at present and, according to the current climate change models predictions, the problem will be amplified in the future. In order to deal with this issue, application of strategies aimed to optimize the water resources in agriculture and to increase water use efficiency have become essential. On the one hand, it is important the election of the appropriate irrigation system for each particular case. On the other hand, identify the best management options for that specific irrigation system is crucial to optimize the available water resources without affecting yield. When using water saving strategies, however, it is a must to monitor the soil and/or crop water status in order to know the level of stress reached by the plants and to avoid levels that could lead to detrimental effects on yield. Stem water potential, ψstem, expressing the instantaneous condition of crop water stress, is considered a robust indicator of crop water status. The main objective of this study was to assess the performance of a surface (DI) and subsurface (SDI) drip irrigation system in a citrus orchard with 7 (DI7, SDI7) or 14 emitters (DI14, SDI14) per plant, in terms of irrigation water use efficiency (IWUE) and possible amount of water saving. The experiment was carried out in 2014 and 2015 in Alberique, Spain, (39˚ 7'31" N, 0˚ 33'17" W), in a commercial orchard (Citrus clementina, Hort. ex Tan. 'Arrufatina') in which four different treatments with three replications (12 sub-plots) were prepared according to a complete randomized block design. Irrigation doses and timing were scheduled based on the estimated maximum crop evapotranspiration corrected according to measurements of ψstem and soil water content, and weather forecasts. In order to limit the maximum crop water stress, the thresholds of ψstem were assumed in the range between -0.8 and -1.0 MPa from January to June and between -1.0 and -1

  4. Apical extrusion of debris and irrigants using ProTaper hand, M-two rotary and WaveOne single file reciprocating system: An ex vivo study.

    Science.gov (United States)

    Singh, Abhishek; Arunagiri, Doraiswamy; Pushpa, Shankarappa; Sawhny, Asheesh; Misra, Abhinav; Khetan, Kirti

    2015-01-01

    The purpose of this ex vivo study was to evaluate and compare the weight of debris and volume of irrigant extruded apically from teeth using different preparation techniques. Thirty extracted human mandibular premolars with single canals and similar lengths were instrumented using hand ProTaper F2 (25, 0.08; Dentsply Maillefer, Ballaigues, Switzerland), M-two (25, 0.06; VDW, Munich, Germany) and WaveOne Primary (25, 0.08; Dentsply Maillefer, Ballaigues, Switzerland). Debris and irrigant extruded during instrumentation were collected into preweighed Eppendorf tubes. The volume of the irrigant was measured, and then the tubes were stored in an incubator at 70°C for 2 days. The Eppendorf tubes were weighed to obtain the final weight when the extruded debris was included. Three consecutive weights were obtained for each tube. Data were statistically analyzed by one-way analysis of variance and Student's t-test. There were no statistically significant differences among the groups. The WaveOne reciprocating system showed the maximum amount of apical extrusion of debris and irrigant among all the groups. The least amount of debris and irrigant was observed in ProTaper hand instrument (P > 0.05). All instrumentation techniques were associated with debris and irrigant extrusion.

  5. Atributos do solo sob pastagens em sistema de sequeiro e irrigado Soil attributes under pasture system with and without irrigation

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Pereira

    2009-04-01

    Jacq. cv. Tanzania and bread grass [Brachiaria brizantha (Hochst ex A. Rich. Stapf. cv. Marandu], with and without irrigation, in the municipality of Rio Verde, Goiás State, Brazil. The experiment was carried out on an oxisol soil at the Comigo Technological Center, in 16 plots of 450m² each. The experimental design used was the completely randomized blocks with four replications. The treatments consisted of two grass species, Tanzania grass (Panicum maximum and bread grass (Brachiaria brizantha and two irrigation treatments, with and without irrigation. The following attributes were determined: aggregate stability, pH, calcium, magnesium, potassium, phosphorus, potential acidity, cation exchange capacity, base saturation, and organic matter content. The chemical attributes varied in both layers mainly due to the liming and fertilization of the soil, independently of the irrigation system. The treatments with Tanzania grass and bread grass without irrigation presented the highest organic matter content and the highest values of DMG. Most of the aggregates had a diameter larger than 2.0 mm. The irrigation management did not affect the dry mass of the grasses studied.

  6. Impacto de los sistemas de riego por goteo en arándanos Impact of drip irrigation systems in blueberries

    Directory of Open Access Journals (Sweden)

    Alejandro Pannunzio

    2011-01-01

    Full Text Available El ensayo examinó los efectos de diferentes sistemas de riego por goteo en el rendimiento de la variedad O´Neal de arándano (Vaccinium corymbosum L. El estudio se realizó en Zarate (33º 41’ S y 59º 41’ W, provincia de Buenos Aires, Argentina. El cultivo se implantó en agosto de 2001, la primera cosecha se efectuó en octubre de 2003. El objetivo fue determinar cual era el sistema de riego por goteo que maximizaba el rendimiento, siendo los tratamientos, un lateral de tubería de goteo por fila de plantas con goteros a 40 cm (T1 y dos laterales de tubería de goteo con goteros a 20 cm por fila de plantas (T2. El porcentaje de suelo mojado por sistema se incrementa a medida que aumenta el número de emisores por metro lineal. El diseño experimental fue de bloques completamente aleatorizados, con bloques de cinco plantas y cinco repeticiones por tratamiento. La cosecha de 2003, reportó rendimientos de 2436 kg ha-1 para el tratamiento T1 y de 4335 kg ha-1 para tratamiento T2. El mojado parcial del suelo que realiza el tratamiento T1, de menor cantidad de goteros por metro lineal, no es suficiente para mojar un porcentaje de suelo compatible con altos rendimientos.The experiment examined the effects of different drip irrigation systems in an O´Neal variety of blueberry (Vaccinium corymbosum L. It was contucted at Zarate (33º 41’ S and 59º 41’ W, Buenos Aires, Argentina. Plants of the experiment were planted in August of 2001, after one year in nursery. The first harvest was realized in October of 2003. The main scope of the experiment was to find the irrigation system which maximized yields. Treatments were: one drip irrigation line with drippers at 40 cm (T1 and two laterals with drippers at 20 cm per row (T2. The experiment was conducted in a completely randomized block design, each one with 5 plants and 5 replications. During the harvest of October and November of 2003, reported yields were 2436 kg ha-1 for the treatment T1 and

  7. Key Challenges and Opportunities for Conjunctive Management of Surface and Groundwater in Mega-Irrigation Systems: Lower Indus, Pakistan

    Directory of Open Access Journals (Sweden)

    Frank van Steenbergen

    2015-11-01

    Full Text Available This paper focuses on the scope of conjunctive management in the Lower Indus part of the Indus Basin Irrigation System (IBIS, and the contribution this could make towards food security and socio-economic development. The total Gross Command Area (GCA of the Lower Indus is 5.92 Mha, with a cultivable command area (CCA of 5.43 Mha, most of which is in Sindh Province. There is a limited use of groundwater in Sindh (about 4.3 Billion Cubic Meter (BCM for two reasons: first, there is a large area where groundwater is saline; and second, there is a high surface irrigation supply to most of the canal commands, e.g., average annual supply to rice command is 1723 mm, close to the annual reference crop evapotranspiration for the area, while there is an additional annual rainfall of about 200 mm. These high irrigation allocations, even in areas where groundwater is fresh, create strong disincentives for farmers to use groundwater. Consequently, areas are waterlogged to the extent of 50% and 70% before and after the monsoon, respectively, which contributes to surface salinity through capillary rise. In Sindh, about 74%–80% of the available groundwater recharge is lost in the form of non-beneficial evaporation. This gives rise to low cropping intensities and yields compared to fresh groundwater areas elsewhere in the IBIS. The drought of 1999–2002 has demonstrated a reduction in waterlogging without any corresponding reduction in crop yields. Therefore, in order to efficiently meet current water requirements of all the sectors, i.e., agriculture, domestic and industrial, an ab initio level of water reallocation and efficient water management, with consideration to groundwater quality and its safe yield, in various areas are recommended. This might systematically reduce the waterlogged areas, support greater cropping intensity than is currently being practiced, and free up water for horizontal expansion, such as in the Thar Desert.

  8. System and prospects of China's intercity rail transit technology

    Science.gov (United States)

    Gong, Ming

    2018-06-01

    City clusters and metropolitan areas in China are flourishing in the midst of the deepening urbanization in the country, thereby resulting in the emergence of intercity rail transit. Intercity railways connect mainline and urban railways for an integrated regional transportation system that underpins and leads the development of city clusters and metropolitan areas. This study explores the development mode and service characteristics of intercity rail transit, as well as proposes overviews on this system and prospects of its future technology in China.

  9. KOEFISIEN TANAMAN PADI SAWAH PADA SISTEM IRIGASI HEMAT AIR Crop Coefficient for Paddy Rice Field under Water Saving Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Joko Sujono

    2012-05-01

    Full Text Available Traditional irrigation for paddy rice is the leading of consumer of water, about 80 % of the water resource availabilityused for irrigation purpose. This phenomenon is related to the way how to estimate the crop water requirement where crop coefficient for paddy rice (k (Prosida is always greater than one starting from planting up to nearly harvesting. In this research, a number of water saving irrigations (WSI systems for paddy rice cultivation using pots such asalternate wetting and drying (AWD, shallow water depth with wetting and drying (SWD, semi-dry cultivation (SDC, system of rice intensification (SRI, and  AWD with mulch (AWD-Mul were applied. The amount of irrigated water and when it should be irrigated depend on evapotranspiration rate, soil moisture condition and the WSI system used. For this purpose, daily measurement of the pot weight was carried out. Crop coefficient (k  is then caluculated as a cratio between crop and reference evapotranspiration computed using Penman-Montheit  method. Results show that up to 45 days after transplanting, the k of WSI treatments were around half of the k (Prosida values currently used for computing the water requirement, whereas at the productive stage the k of WSI systems were relatively equal (AWD, SDC to or greater (SRI, SWD than the k (Prosida. Based on the the k values, the AWD and the SDC systems could save much water compared to the SRI or the SWD. Water saving could be increased by applying the AWD with mulch. ABSTRAK Irigasi padi sawah dengan sistem tradisional merupakan sistem irigasi  yang boros air, hampir 80 % sumber air yang ada untuk irigasi. Hal ini tidak terlepas dari perhitungan kebutuhan air tanaman dengan nilai koefisien tanaman (k menurut Standar Perencanaan Irigasi (Prosida selalu lebih besar dari satu mulai dari tanam hingga menjelang panen.Dalam penelitian ini beberapa metoda budidaya padi hemat air seperti alternate wetting and drying (AWD, shallow water depth

  10. China's health care system reform: Progress and prospects.

    Science.gov (United States)

    Li, Ling; Fu, Hongqiao

    2017-07-01

    This paper discusses the progress and prospects of China's complex health care reform beginning in 2009. The Chinese government's undertaking of systemic reform has achieved laudable achievements, including the expansion of social health insurance, the reform of public hospitals, and the strengthening of primary care. An innovative policy tool in China, policy experimentation under hierarchy, played an important role in facilitating these achievements. However, China still faces gaps and challenges in creating a single payer system, restructuring the public hospitals, and establishing an integrated delivery system. Recently, China issued the 13th 5-year plan for medical reform, setting forth the goals, policy priorities, and strategies for health reform in the following 5 years. Moreover, the Chinese government announced the "Healthy China 2030" blueprint in October 2016, which has the goals of providing universal health security for all citizens by 2030. By examining these policy priorities against the existing gaps and challenges, we conclude that China's health care reform is heading in the right direction. To effectively implement these policies, we recommend that China should take advantage of policy experimentation to mobilize bottom-up initiatives and encourage innovations. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Spatial Zonation Model of Local Irrigation System Sustainability (A Case of Subak System in Bali

    Directory of Open Access Journals (Sweden)

    I Putu Sriartha

    2016-02-01

    Full Text Available This study was aimed at designing a spatial zonation model of a subak sustainability type based on the internal and external dimentions from 69 subaks in three districts in Badung regency. The internal dimention was measured based on subak capability index in implementing Tri Hita Karana (THK philosophy. The external dimention was measured by using index of four variables, namely: road density, population density, social economic facilities, and number of nonfarmer families.The data were analyzed using descriptive quantitative technique and spatial analysis using Geographical Information System (GIS software. The results found three zones of subak sustainability type, spatially follows the principle of distance decay of the growth of tourism and city center. Unsustainable - less sustainable subak zone dominates short distance zone, sustainable - less sustainable subak zone dominates transitional zone, while sustainable subak zone dominates long distance zone. To protect subak from destruction, less sustainable subaks have to be restored into sustainable ones and the sustainable subaks should be made eternal/exclusive subaks

  12. Sensing technologies for precision irrigation

    CERN Document Server

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

    2014-01-01

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

  13. Development of a decision support system for precision management of conjunctive use of treated wastewater for irrigation in Oman

    Directory of Open Access Journals (Sweden)

    Hemanatha P. W. Jayasuriya

    2018-01-01

    Full Text Available This research aimed at finding alternative options for conjunctive use of treated wastewater (TW with groundwater (GW minimizing the irrigation water from aquifers in the Al-Batinah region with the assistance of a Decision Support System (DSS. Oman is facing a three-facet problem of lowering of GW table, wastewater over-production and excess TW. Approved guidelines for use of TW with tertiary treatments are of two classes: class-A (for vegetables consumed raw, class-B (after cooking. The developed DSS is comprised of four management subsystems: (1 data management in Excel, (2 model and knowledge management by macro programming in Excel, (3 with linear programming (LP optimization models including transportation algorithms, and (4 user interface with Excel or Visual Basic (VB. The results are based on two extreme scenarios: zero TW excess, and zero GW used for irrigation. The DSS could predict water balance for number of crop rotations, and based on adjustable cost variables farmer profit margins could be created. Crop selections and rotation could be done using LP optimizations while transportation algorithm could organize best locations and capacities for treatment plants and the wastewater collection and transportation to farming areas via treatment plants. The developed DSS will be very useful as a water management, optimization and planning tool.

  14. Influential aspects of glacial resource for establishing Kuhl system (gravity flow irrigation) in the Hindu Kush, Karakoram and Himalaya ranges.

    Science.gov (United States)

    Ashraf, Arshad; Iqbal, Ayesha

    2018-04-27

    The meltwater components play an important role in the hydrological regime of the Hindu Kush, Karakorum and Himalaya (HKH) region, in terms of high demand of water for food and fiber from snow and glacial resource. The communities of Himalayan mountains are facing challenges of food security owing to lack of the resource information for meeting their water requirements. In this study, suitability index approach was adopted to assess glacier resource potential for establishing kuhl irrigation system in HKH ranges of Pakistan. The basis of indexing is glacier accessibility and water yield potential of the glacial resource for irrigation estimated in terms of number and ice reserve of the glaciers. The suitability index was found good for about 1.4% glaciers constituting about 80% of the total ice reserves of the HKH region. Medium suitability constitutes about 36.1% glaciers with 12.6% of the total ice reserves, while low suitability was assessed for about 60% glaciers containing 1.5% ice reserves only. Maximum unit glacial reserve was estimated for Shigar basin, i.e., 1.44 km 3 , and among HKH ranges, 0.46 km 3 for the Karakoram range. A regular monitoring of the glacial resource would prove helpful in assessing vulnerability of this resource to climate change in the high Himalayan region in future. Copyright © 2018. Published by Elsevier B.V.

  15. Desalination Using the Condensation Irrigation System, A Case Study of the Research Farm of Shahid Chamran University of Ahvaz

    Directory of Open Access Journals (Sweden)

    Bagher Yousefi

    2015-07-01

    Full Text Available Condensation Irrigation (CI is a combination of simultaneous desalination and irrigation/drinking water production. As saline water evaporates in a solar distiller and the hot and humid air is transferred into an underground pipeline, fresh water will condense on the inner pipe surface due to cooling of air by the ground. The water thus condensed infiltrates into the soil through pores in the perforated drainage pipes laid in the ground to transfer the humidified air. In this study, the CI system was developed using common buried pipes to determine the amount of water produced. In this setup, condensed water is collected at the end of the pipe to be used for drinking. Observations and calculations indicated a mean water production capacity of 4 liters every 8 hours along a pipe 25m long. Less water was produced on the first day because some of the water was lost to the wetting of the internal pipe walls. Finally, examination of temperature effects revealed that water production along the pipe reduces as we move farther away from the inlet part of the pipe.

  16. Regulatory system reform of occupational health and safety in China.

    Science.gov (United States)

    Wu, Fenghong; Chi, Yan

    2015-01-01

    With the explosive economic growth and social development, China's regulatory system of occupational health and safety now faces more and more challenges. This article reviews the history of regulatory system of occupational health and safety in China, as well as the current reform of this regulatory system in the country. Comprehensive, a range of laws, regulations and standards that promulgated by Chinese government, duties and responsibilities of the regulatory departments are described. Problems of current regulatory system, the ongoing adjustments and changes for modifying and improving regulatory system are discussed. The aim of reform and the incentives to drive forward more health and safety conditions in workplaces are also outlined.

  17. Groundwater-fed irrigation impacts spatially distributed temporal scaling behavior of the natural system: a spatio-temporal framework for understanding water management impacts

    International Nuclear Information System (INIS)

    Condon, Laura E; Maxwell, Reed M

    2014-01-01

    Regional scale water management analysis increasingly relies on integrated modeling tools. Much recent work has focused on groundwater–surface water interactions and feedbacks. However, to our knowledge, no study has explicitly considered impacts of management operations on the temporal dynamics of the natural system. Here, we simulate twenty years of hourly moisture dependent, groundwater-fed irrigation using a three-dimensional, fully integrated, hydrologic model (ParFlow-CLM). Results highlight interconnections between irrigation demand, groundwater oscillation frequency and latent heat flux variability not previously demonstrated. Additionally, the three-dimensional model used allows for novel consideration of spatial patterns in temporal dynamics. Latent heat flux and water table depth both display spatial organization in temporal scaling, an important finding given the spatial homogeneity and weak scaling observed in atmospheric forcings. Pumping and irrigation amplify high frequency (sub-annual) variability while attenuating low frequency (inter-annual) variability. Irrigation also intensifies scaling within irrigated areas, essentially increasing temporal memory in both the surface and the subsurface. These findings demonstrate management impacts that extend beyond traditional water balance considerations to the fundamental behavior of the system itself. This is an important step to better understanding groundwater’s role as a buffer for natural variability and the impact that water management has on this capacity. (paper)

  18. Water Pricing and Implementation Strategies for the Sustainability of an Irrigation System: A Case Study within the Command Area of the Rakh Branch Canal

    Directory of Open Access Journals (Sweden)

    Muhammad Uzair Qamar

    2018-04-01

    Full Text Available The command area of the Rakh branch canal grows wheat, sugarcane, and rice crops in abundance. The canal water, which is trivial for irrigating these crops, is conveyed to the farms through the network of canals and distributaries. For the maintenance of this vast infrastructure; the end users are charged on a seasonal basis. The present water charges are severely criticized for not being adequate to properly manage the entire infrastructure. We use the residual value to determine the value of the irrigation water and then based on the quantity of irrigation water supplied to farm land coupled with the infrastructure maintenance cost, full cost recovery figures are executed for the study area, and policy recommendations are made for the implementation of the full cost recovery system. The approach is unique in the sense that the pricings are based on the actual quantity of water conveyed to the field for irrigating crops. The results of our analysis showed that the canal water is severely under charged in the culturable command area of selected distributaries, thus negating the plan of having a self-sustainable irrigation system.

  19. a System Dynamics Approach for Looking at the Human and Environmental Interactions of Community-Based Irrigation Systems in New Mexico

    Science.gov (United States)

    Ochoa, C. G.; Tidwell, V. C.

    2012-12-01

    In the arid southwestern United States community water management systems have adapted to cope with climate variability and with socio-cultural and economic changes that have occurred since the establishment of these systems more than 300 years ago. In New Mexico, the community-based irrigation systems were established by Spanish settlers and have endured climate variability in the form of low levels of precipitation and have prevailed over important socio-political changes including the transfer of territory between Spain and Mexico, and between Mexico and the United States. Because of their inherent nature of integrating land and water use with society involvement these community-based systems have multiple and complex economic, ecological, and cultural interactions. Current urban population growth and more variable climate conditions are adding pressure to the survival of these systems. We are conducting a multi-disciplinary research project that focuses on characterizing these intrinsically complex human and natural interactions in three community-based irrigation systems in northern New Mexico. We are using a system dynamics approach to integrate different hydrological, ecological, socio-cultural and economic aspects of these three irrigation systems. Coupled with intensive field data collection, we are building a system dynamics model that will enable us to simulate important linkages and interactions between environmental and human elements occurring in each of these water management systems. We will test different climate variability and population growth scenarios and the expectation is that we will be able to identify critical tipping points of these systems. Results from this model can be used to inform policy recommendations relevant to the environment and to urban and agricultural land use planning in the arid southwestern United States.

  20. A matter of relationships: Actor-networks of colonial rule in the Gezira irrigation system, Sudan

    Directory of Open Access Journals (Sweden)

    Maurits Ertsen

    2016-06-01

    Full Text Available In the first half of the 20th century, colonial rulers, a British firm and Sudanese farmers changed the Gezira Plain in Sudan into a large-scale irrigated cotton scheme. Gezira continues to be in use up to date. Its story shows how the abstract concept 'development' is shaped through the agency of humans and non-humans alike in government offices and muddy fields. Gezira provides a well-suited starting point for moving into the networks of development without any pre-suggested division in terms of levels, contexts or relations. Hierarchies, arenas and institutions do exist. Such power relations are associations between humans and non-humans: relatively stable relations are typically produced when non-human agency is involved, for example through books, roads, and money. The Gezira case shows the potential of actor-network theory in building and understanding of conceptual and empirical links between water, infrastructure and political rule.

  1. Portable photovoltaic irrigation pumps

    Energy Technology Data Exchange (ETDEWEB)

    Furber, J. D.

    1980-07-01

    Experiences in developing a solar-powered irrigation pump to meet the needs of poor farmers in developing nations are summarized. The design which evolved is small and portable, employing a high-efficiency electric pump, powered by photovoltaic panels. Particular emphasis is placed on how the system works, and on early field problems experienced with the first prototypes. The resolution of these problems and the performance of actual systems in various countries is presented and user responses are noted.

  2. Irrigated Area Maps and Statistics of India Using Remote Sensing and National Statistics

    Directory of Open Access Journals (Sweden)

    Prasad S. Thenkabail

    2009-04-01

    Full Text Available The goal of this research was to compare the remote-sensing derived irrigated areas with census-derived statistics reported in the national system. India, which has nearly 30% of global annualized irrigated areas (AIAs, and is the leading irrigated area country in the World, along with China, was chosen for the study. Irrigated areas were derived for nominal year 2000 using time-series remote sensing at two spatial resolutions: (a 10-km Advanced Very High Resolution Radiometer (AVHRR and (b 500-m Moderate Resolution Imaging Spectroradiometer (MODIS. These areas were compared with the Indian National Statistical Data on irrigated areas reported by the: (a Directorate of Economics and Statistics (DES of the Ministry of Agriculture (MOA, and (b Ministry of Water Resources (MoWR. A state-by-state comparison of remote sensing derived irrigated areas when compared with MoWR derived irrigation potential utilized (IPU, an equivalent of AIA, provided a high degree of correlation with R2 values of: (a 0.79 with 10-km, and (b 0.85 with MODIS 500-m. However, the remote sensing derived irrigated area estimates for India were consistently higher than the irrigated areas reported by the national statistics. The remote sensing derived total area available for irrigation (TAAI, which does not consider intensity of irrigation, was 101 million hectares (Mha using 10-km and 113 Mha using 500-m. The AIAs, which considers intensity of irrigation, was 132 Mha using 10-km and 146 Mha using 500-m. In contrast the IPU, an equivalent of AIAs, as reported by MoWR was 83 Mha. There are “large variations” in irrigated area statistics reported, even between two ministries (e.g., Directorate of Statistics of Ministry of Agriculture and Ministry of Water Resources of the same national system. The causes include: (a reluctance on part of the states to furnish irrigated area data in view of their vested interests in sharing of water, and (b reporting of large volumes of data

  3. Compressibilidade de um solo sob sistemas de pastejo rotacionado intensivo irrigado e não irrigado Soil compressibility under non-irrigated and irrigated short duration grazing systems

    Directory of Open Access Journals (Sweden)

    C. L. R. Lima

    2004-12-01

    Full Text Available O incremento da produtividade das pastagens tem sido associado ao comportamento à compressão dos solos. Os objetivos deste trabalho foram: quantificar as curvas de compressão e a pressão de preconsolidação em sistemas de pastejo intensivo rotacionado irrigado e não irrigado. Foram coletadas 96 amostras indeformadas de solo em quatro ciclos sucessivos de pastejo instalado com capim Tanzânia (Panicum maximum Jacq. em um Argissolo Vermelho. Após saturadas com água e equilibradas no potencial (psi: -10 kPa, as amostras foram pesadas e submetidas ao ensaio de compressão uniaxial com a aplicação sucessiva e contínua de pressões de 25, 50, 100, 200, 400, 600, 800, 1.000, 1.300 e 1.600 kPa. Os resultados comprovaram a hipótese de que houve diferença na compressibilidade do solo sob os sistemas de pastejo rotacionado intensivo irrigado e não irrigado. A maior compactação inicial verificada no sistema de pastejo rotacionado intensivo irrigado favoreceu o deslocamento das curvas de compressão uniaxial para valores superiores de densidade do solo. A pressão de preconsolidação foi significativamente superior no quarto ciclo de pastejo no sistema de pastejo rotacionado intensivo irrigado em relação ao sistema pastejo rotacionado intensivo não irrigado.Increment in pasture productivity has been associated with the understanding of the soil behavior under compression. The objective of this research was to quantify (a the compression curves and (b the preconsolidation pressure of the soils under non-irrigated and irrigated short duration grazing systems. Ninety-six undisturbed soil samples were taken from the four successive pasture cycles of Tanzania grass (Panicum maximum Jacq. in a Hapludalf. The samples were saturated in water and equilibrated at the matrix potential (psi: -10 kPa and then were weighed and submitted to an uniaxial compression test, applying the following pressures: 25, 50, 100, 200, 400, 600, 800, 1,000, 1,300, and

  4. Straw decomposition of nitrogen-fertilized grasses intercropped with irrigated maize in an integrated crop-livestock system

    Directory of Open Access Journals (Sweden)

    Cristiano Magalhães Pariz

    2011-12-01

    Full Text Available The greatest limitation to the sustainability of no-till systems in Cerrado environments is the low quantity and rapid decomposition of straw left on the soil surface between fall and spring, due to water deficit and high temperatures. In the 2008/2009 growing season, in an area under center pivot irrigation in Selvíria, State of Mato Grosso do Sul, Brazil, this study evaluated the lignin/total N ratio of grass dry matter , and N, P and K deposition on the soil surface and decomposition of straw of Panicum maximum cv. Tanzânia, P. maximum cv. Mombaça, Brachiaria. brizantha cv. Marandu and B. ruziziensis, and the influence of N fertilization in winter/spring grown intercropped with maize, on a dystroferric Red Latosol (Oxisol. The experiment was arranged in a randomized block design in split-plots; the plots were represented by eight maize intercropping systems with grasses (sown together with maize or at the time of N side dressing. Subplots consisted of N rates (0, 200, 400 and 800 kg ha-1 year-1 sidedressed as urea (rates split in four applications at harvests in winter/spring, as well as evaluation of the straw decomposition time by the litter bag method (15, 30, 60, 90, 120, and 180 days after straw chopping. Nitrogen fertilization in winter/spring of P. maximum cv. Tanzânia, P. maximum cv. Mombaça, B. brizantha cv. Marandu and B. ruziziensis after intercropping with irrigated maize in an integrated crop-livestock system under no-tillage proved to be a technically feasible alternative to increase the input of straw and N, P and K left on the soil surface, required for the sustainability of the system, since the low lignin/N ratio of straw combined with high temperatures accelerated straw decomposition, reaching approximately 30 % of the initial amount, 90 days after straw chopping.

  5. Estimation of soil salinity in a drip irrigation system by using joint inversion of multicoil electromagnetic induction measurements

    KAUST Repository

    Jadoon, Khan Zaib

    2015-05-12

    Low frequency electromagnetic induction (EMI) is becoming a useful tool for soil characterization due to its fast measurement capability and sensitivity to soil moisture and salinity. In this research, a new EMI system (the CMD mini-Explorer) is used for subsurface characterization of soil salinity in a drip irrigation system via a joint inversion approach of multiconfiguration EMI measurements. EMI measurements were conducted across a farm where Acacia trees are irrigated with brackish water. In situ measurements of vertical bulk electrical conductivity (σb) were recorded in different pits along one of the transects to calibrate the EMI measurements and to compare with the modeled electrical conductivity (σ) obtained by the joint inversion of multiconfiguration EMI measurements. Estimates of σ were then converted into the universal standard of soil salinity measurement (i.e., electrical conductivity of a saturated soil paste extract – ECe). Soil apparent electrical conductivity (ECa) was repeatedly measured with the CMD mini-Explorer to investigate the temperature stability of the new system at a fixed location, where the ambient air temperature increased from 26°C to 46°C. Results indicate that the new EMI system is very stable in high temperature environments, especially above 40°C, where most other approaches give unstable measurements. In addition, the distribution pattern of soil salinity is well estimated quantitatively by the joint inversion of multicomponent EMI measurements. The approach of joint inversion of EMI measurements allows for the quantitative mapping of the soil salinity distribution pattern and can be utilized for the management of soil salinity.

  6. Effect of inter-annual variability in pasture growth and irrigation response on farm productivity and profitability based on biophysical and farm systems modelling.

    Science.gov (United States)

    Vogeler, Iris; Mackay, Alec; Vibart, Ronaldo; Rendel, John; Beautrais, Josef; Dennis, Samuel

    2016-09-15

    Farm system and nutrient budget models are increasingly being used in analysis to inform on farm decision making and evaluate land use policy options at regional scales. These analyses are generally based on the use of average annual pasture yields. In New Zealand (NZ), like in many countries, there is considerable inter-annual variation in pasture growth rates, due to climate. In this study a modelling approach was used to (i) include inter-annual variability as an integral part of the analysis and (ii) test the approach in an economic analysis of irrigation in a case study within the Hawkes Bay Region of New Zealand. The Agricultural Production Systems Simulator (APSIM) was used to generate pasture dry matter yields (DMY) for 20 different years and under both dryland and irrigation. The generated DMY were linked to outputs from farm-scale modelling for both Sheep and Beef Systems (Farmaxx Pro) and Dairy Systems (Farmax® Dairy Pro) to calculate farm production over 20 different years. Variation in DMY and associated livestock production due to inter-annual variation in climate was large, with a coefficient of variations up to 20%. Irrigation decreased this inter-annual variation. On average irrigation, with unlimited available water, increased income by $831 to 1195/ha, but when irrigation was limited to 250mm/ha/year income only increased by $525 to 883/ha. Using pasture responses in individual years to capturing the inter-annual variation, rather than the pasture response averaged over 20years resulted in lower financial benefits. In the case study income from irrigation based on an average year were 10 to >20% higher compared with those obtained from individual years. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Integrated assessment and scenarios simulation of urban water security system in the southwest of China with system dynamics analysis.

    Science.gov (United States)

    Yin, Su; Dongjie, Guan; Weici, Su; Weijun, Gao

    2017-11-01

    The demand for global freshwater is growing, while global freshwater available for human use is limited within a certain time and space. Its security has significant impacts on both the socio-economic system and ecological system. Recently, studies have focused on the urban water security system (UWSS) in terms of either water quantity or water quality. In this study, water resources, water environment, and water disaster issues in the UWSS were combined to establish an evaluation index system with system dynamics (SD) and geographic information systems (GIS). The GIS method performs qualitative analysis from the perspective of the spatial dimension; meanwhile, the SD method performs quantitative calculation about related water security problems from the perspective of the temporal dimension. We established a UWSS model for Guizhou province, China to analyze influencing factors, main driving factors, and system variation law, by using the SD method. We simulated the water security system from 2005 to 2025 under four scenarios (Guiyang scenario, Zunyi scenario, Bijie scenario and combined scenario). The results demonstrate that: (1) the severity of water security in cities is ranked as follows: three cities are secure in Guizhou province, four cities are in basic security and two cities are in a situation of insecurity from the spatial dimension of GIS through water security synthesis; and (2) the major driving factors of UWSS in Guizhou province include agricultural irrigation water demand, soil and water losses area, a ratio increase to the standard of water quality, and investment in environmental protection. A combined scenario is the best solution for UWSS by 2025 in Guizhou province under the four scenarios from the temporal dimension of SD. The results of this study provide a useful suggestion for the management of freshwater for the cities of Guizhou province in southwest China.

  8. The Reform of Management System of Accountants in China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The common existing problems of the false processing of accounting information in China and the solution--the appointment system of accountants are analyzed in this paper, it is proposed that the reform of management systems of accountants--the appointment system of accountants should be applied temporally in particular conditions.

  9. Reforming the Public Agricultural Extension System in China ...

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

    Reforming the Public Agricultural Extension System in China : Supporting Rural Innovation. The public agricultural extension system has played a critical role in Chinese agricultural development over the past few decades. There is growing evidence that since the mid-1990s the system has failed to provide new and ...

  10. Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study

    International Nuclear Information System (INIS)

    Gao, Bing; Ju, Xiaotang; Su, Fang; Meng, Qingfeng; Oenema, Oene; Christie, Peter; Chen, Xinping; Zhang, Fusuo

    2014-01-01

    The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N 2 O) and methane (CH 4 ) emissions of conventional and optimized winter wheat–summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat–summer maize (or soybean)–spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N 2 O emissions plus CH 4 uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat–summer maize–spring maize system. Net uptake of CH 4 by the soil was little affected by cropping system. Average N 2 O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat–summer maize–spring maize system has considerable potential to decrease water and N use and decrease N 2 O emissions while maintaining high grain yields and sustainable use of groundwater. - Highlights: • Yields, resource use efficiency and N 2 O + CH 4 emission differ among cropping systems. • An

  11. Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Bing [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Ju, Xiaotang, E-mail: juxt@cau.edu.cn [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Su, Fang; Meng, Qingfeng [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Oenema, Oene [Wageningen University and Research, Alterra, Wageningen (Netherlands); Christie, Peter [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Agri-Environment Branch, Agri-Food and Biosciences Institute, Belfast BT9 5PX (United Kingdom); Chen, Xinping; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China)

    2014-02-01

    The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N{sub 2}O) and methane (CH{sub 4}) emissions of conventional and optimized winter wheat–summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat–summer maize (or soybean)–spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N{sub 2}O emissions plus CH{sub 4} uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat–summer maize–spring maize system. Net uptake of CH{sub 4} by the soil was little affected by cropping system. Average N{sub 2}O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat–summer maize–spring maize system has considerable potential to decrease water and N use and decrease N{sub 2}O emissions while maintaining high grain yields and sustainable use of groundwater. - Highlights: • Yields, resource use efficiency and N{sub 2}O + CH{sub 4} emission

  12. Modernized Irrigation Technologies in West Africa

    Directory of Open Access Journals (Sweden)

    Hakan Büyükcangaz

    2017-12-01

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

  13. Impact of the reusing of food manufacturing wastewater for irrigation in a closed system on the microbiological quality of the food crops.

    Science.gov (United States)

    Beneduce, Luciano; Gatta, Giuseppe; Bevilacqua, Antonio; Libutti, Angela; Tarantino, Emanuele; Bellucci, Micol; Troiano, Eleonora; Spano, Giuseppe

    2017-11-02

    In order to evaluate if the reuse of food industry treated wastewater is compatible for irrigation of food crops, without increased health risk, in the present study a cropping system, in which ground water and treated wastewater were used for irrigation of tomato and broccoli, during consecutive crop seasons was monitored. Water, crop environment and final products were monitored for microbial indicators and pathogenic bacteria, by conventional and molecular methods. The microbial quality of the irrigation waters influenced sporadically the presence of microbial indicators in soil. No water sample was found positive for pathogenic bacteria, independently from the source. Salmonella spp. and Listeria monocytogenes were detected in soil samples, independently from the irrigation water source. No pathogen was found to contaminate tomato plants, while Listeria monocytogenes and E. coli O157:H7 were detected on broccoli plant, but when final produce were harvested, no pathogen was detected on edible part. The level of microbial indicators and detection of pathogenic bacteria in field and plant was not dependent upon wastewater used. Our results, suggest that reuse of food industry wastewater for irrigation of agricultural crop can be applied without significant increase of potential health risk related to microbial quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Environmental Kuznets Curve Analysis of the Economic Development and Nonpoint Source Pollution in the Ningxia Yellow River Irrigation Districts in China

    Directory of Open Access Journals (Sweden)

    Chunlan Mao

    2013-01-01

    Full Text Available This study applies the environmental Kuznets curve to test the relationship between the regional economic growth and the different types of agricultural nonpoint source pollution loads in the Ningxia Yellow River irrigation area by using the Johnes export coefficient method. Results show that the pollution load generated by crop cultivation and livestock-breeding industries in the Ningxia Yellow River irrigation area shows an inverted U-shaped feature; however, this feature is absent in living-sewage pollution load. Crop pollution has shown a decreasing trend since 1997 because of the increased per capita income of farmers. Livestock-breeding pollution load reached its turning point when the per capita income of farmers reached 8386.74 RMB. Therefore, an increase in the per capita income of farmers corresponds to an increase in the livestock-breeding pollution load in the Ningxia Yellow River irrigation area.

  15. Environmental Kuznets curve analysis of the economic development and nonpoint source pollution in the Ningxia Yellow River irrigation districts in China.

    Science.gov (United States)

    Mao, Chunlan; Zhai, Ningning; Yang, Jingchao; Feng, Yongzhong; Cao, Yanchun; Han, Xinhui; Ren, Guangxin; Yang, Gaihe; Meng, Qing-xiang

    2013-01-01

    This study applies the environmental Kuznets curve to test the relationship between the regional economic growth and the different types of agricultural nonpoint source pollution loads in the Ningxia Yellow River irrigation area by using the Johnes export coefficient method. Results show that the pollution load generated by crop cultivation and livestock-breeding industries in the Ningxia Yellow River irrigation area shows an inverted U-shaped feature; however, this feature is absent in living-sewage pollution load. Crop pollution has shown a decreasing trend since 1997 because of the increased per capita income of farmers. Livestock-breeding pollution load reached its turning point when the per capita income of farmers reached 8386.74 RMB. Therefore, an increase in the per capita income of farmers corresponds to an increase in the livestock-breeding pollution load in the Ningxia Yellow River irrigation area.

  16. Relationship between pure Schistosoma haematobium infection in Upper Egypt and irrigation systems. Part II: Host characteristics. The general prevalence of Schistosoma haematobium, age and sex distribution.

    Science.gov (United States)

    Hammam, H M; Allam, F A; Hassanein, F

    1975-01-01

    The epidemiology of bilharziasis was studied in four villages in Assiut Governorate. These villages were almost similar with respect to their socioeconomic conditions, modes of living, availability and date of introduction of medical services. The first village, Gezirat El-Maabda, has a basin system of irrigation. The other three villages had shifted to the perennial system of irrigation for three years in Nazza Karrar, 26 years in El-Ghorayeb and 95 years in Garf Sarhan and were similar with respect to proximity to water courses. So the only variable of importance between the four villages was the mode of irrigation. Bilharziasis was diagnosed by detection of eggs in urine or faeces. A definitive relationship between the prevalence of S. haematobium infection and the type of irrigation system was further documented. A low prevalence was found in Gezirat El-Maabda (2.95%). In the other three villages a much higher prevalence existed (31.9%, 46.2% & 38.9% in Nazza Karar, El-Ghorayeb and Garf Sarhan respectively). The higher prevalence of S. haematobium in Nazza Karar (31.9%) only three years after introduction of perennial irrigation was a disappointing finding. It can be considered as an evidence against the elaborate measures and precautions planned and incompletely implemented before or after the establishment of Aswan High Dam. Not a single case of S. mansoni was encountered during this study. As regards the age and sex distribution of S. haematobium in the three villages irrigated perennially, a steep rise started at the age group 5-9 years reaching a peak at the age group 10-14 years. In Gezirat El-Maabda the peak was reached at later age (15-19 years). The cause of this difference was explained. Males showed a higher rate of infection than females in almost all age groups of the four village studied.

  17. Urban underground logistics system in China: Opportunities or challenges?

    Directory of Open Access Journals (Sweden)

    Zhilong Chen

    2017-09-01

    Full Text Available An urban underground logistics system (ULS is one important means of solving urban traffic problems that has unique advantages. Freight transportation in China requires a new transportation mode. Therefore, ULS has garnered increasing attention. However, to date, few scholars and practitioners have investigated ULS in China. Although ULS shows good development opportunities, it also faces great challenges. Based on the Macro-environment and situation analysis (PEST-SWOT model, which is a strategic analysis method that combines both SWOT and PEST to effectively identify advantages, disadvantages, opportunities and threats, this paper first uses PEST to analyze the macro-environment of ULS in China and identify its internal factors (i.e., advantages and disadvantages and external factors (i.e., opportunities and threats. Next, based on the SWOT framework, this paper proposes several development strategies and recommendations that provide a comprehensive and novel perspective to the study of ULS in China.

  18. Nitrous oxide, carbon dioxide and methane emissions from irrigated cropping systems as influenced by legumes, manure and fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Ellert, B.H.; Janzen, H.H. [Agriculture and Agri-Food Canada, Lethbridge, AB (Canada)

    2008-04-15

    Irrigated crops in Alberta require higher inputs of nitrogen (N) than rainfed crops. The aim of the study was to determine emissions of nitrous oxide (N{sub 2}O) from the soils of irrigated cropping systems that used inorganic fertilizer N at a site in Alberta. The study measured carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) levels in order to determine net greenhouse gas (GHG) emissions. The exchange of gases between the atmosphere and soil in selected treatments was measured in order to compare the effects of contrasting N inputs. Fluxes were measured bi-weekly from spring 2001 to spring 2004. The time period included annual and perennial legume crops; the termination of a perennial forage crop; manure application; and 2 growing seasons of test crops. Soil surface fluxes were measured using PVC chambers equipped with thermocouples. Gas samples were measured using gas chromatography. A linear least squares method was used to calculate gas concentrations. Results showed that soil CO{sub 2} and N{sub 2}O production rates were intertwined after legume production or manure application, but decoupled during early spring bursts of N{sub 2}O production. Higher soil CO{sub 2} emissions with alfalfa and manure-amended soils suggested that soil oxygen consumption during high CO{sub 2} emission periods may promote N{sub 2}O emissions. Appreciable proportions of N{sub 2}O were emitted outside the growing season. Results suggested that N{sub 2}O leakage is an inevitable hazard of crop production. The study highlighted the importance of understanding and quantifying N{sub 2}O emissions from intensive cropping systems. 22 refs., 4 tabs., 6 figs.

  19. Maximum Plant Uptakes for Water, Nutrients, and Oxygen Are Not Always Met by Irrigation Rate and Distribution in Water-based Cultivation Systems.

    Science.gov (United States)

    Blok, Chris; Jackson, Brian E; Guo, Xianfeng; de Visser, Pieter H B; Marcelis, Leo F M

    2017-01-01

    Growing on rooting media other than soils in situ -i.e., substrate-based growing- allows for higher yields than soil-based growing as transport rates of water, nutrients, and oxygen in substrate surpass those in soil. Possibly water-based growing allows for even higher yields as transport rates of water and nutrients in water surpass those in substrate, even though the transport of oxygen may be more complex. Transport rates can only limit growth when they are below a rate corresponding to maximum plant uptake. Our first objective was to compare Chrysanthemum growth performance for three water-based growing systems with different irrigation. We compared; multi-point irrigation into a pond (DeepFlow); one-point irrigation resulting in a thin film of running water (NutrientFlow) and multi-point irrigation as droplets through air (Aeroponic). Second objective was to compare press pots as propagation medium with nutrient solution as propagation medium. The comparison included DeepFlow water-rooted cuttings with either the stem 1 cm into the nutrient solution or with the stem 1 cm above the nutrient solution. Measurements included fresh weight, dry weight, length, water supply, nutrient supply, and oxygen levels. To account for differences in radiation sum received, crop performance was evaluated with Radiation Use Efficiency (RUE) expressed as dry weight over sum of Photosynthetically Active Radiation. The reference, DeepFlow with substrate-based propagation, showed the highest RUE, even while the oxygen supply provided by irrigation was potentially growth limiting. DeepFlow with water-based propagation showed 15-17% lower RUEs than the reference. NutrientFlow showed 8% lower RUE than the reference, in combination with potentially limiting irrigation supply of nutrients and oxygen. Aeroponic showed RUE levels similar to the reference and Aeroponic had non-limiting irrigation supply of water, nutrients, and oxygen. Water-based propagation affected the subsequent

  20. Irrigation as an Historical Climate Forcing

    Science.gov (United States)

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

    2014-01-01

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

  1. Smart System for Bicarbonate Control in Irrigation for Hydroponic Precision Farming

    Directory of Open Access Journals (Sweden)

    Carlos Cambra

    2018-04-01

    Full Text Available Improving the sustainability in agriculture is nowadays an important challenge. The automation of irrigation processes via low-cost sensors can to spread technological advances in a sector very influenced by economical costs. This article presents an auto-calibrated pH sensor able to detect and adjust the imbalances in the pH levels of the nutrient solution used in hydroponic agriculture. The sensor is composed by a pH probe and a set of micropumps that sequentially pour the different liquid solutions to maintain the sensor calibration and the water samples from the channels that contain the nutrient solution. To implement our architecture, we use an auto-calibrated pH sensor connected to a wireless node. Several nodes compose our wireless sensor networks (WSN to control our greenhouse. The sensors periodically measure the pH level of each hydroponic support and send the information to a data base (DB which stores and analyzes the data to warn farmers about the measures. The data can then be accessed through a user-friendly, web-based interface that can be accessed through the Internet by using desktop or mobile devices. This paper also shows the design and test bench for both the auto-calibrated pH sensor and the wireless network to check their correct operation.

  2. Education System Reform in China after 1978: Some Practical Implications

    Science.gov (United States)

    Sun, Miantao

    2010-01-01

    Purpose: This paper aims to provide an overview of education system reform in China since 1978, and its practical implications. Design/methodology/approach: Data were collected from literature review and interview. An overview of education system reform and its practical implications was found through data analysis. Findings: There has been two…

  3. National Innovation Systems in Brazil, Russia, India, China and ...

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

    Brazil, Russia, India, China and South Africa (BRICS) have put innovation at the centre of their development strategies. In each case, however, there exists scant knowledge about the national innovation system and its impact on the economy. This grant will support a comparative analysis of innovation systems in the five ...

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

    Directory of Open Access Journals (Sweden)

    Liudong Zhang

    2014-01-01

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

  5. The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

    Science.gov (United States)

    Gao, Xuan

    2017-04-01

    Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally

  6. Irrigation and Autocracy

    DEFF Research Database (Denmark)

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

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

  7. Genetic variability in elite barley genotypes based on the agro-morphological characteristics evaluated under irrigated system

    Directory of Open Access Journals (Sweden)

    Renato Fernando Amabile

    Full Text Available ABSTRACT Recently, researches have shown that the Brazilian savannah has a great potential to supply the demand for barley grains. The purpose of this study was to assess the genetic variability in 39 elite barley (Hordeum vulgare L. genotypes based on the agro-morphological traits of a crop irrigated in the savannah system. An irrigation experiment in the design of complete randomized block with four replicates was conducted at Federal District - Brazil. The evaluated traits were: distance from the last knot to the rachis, distance from the flag leaf to rachis, spike length, number of grains by ear, flag leaf area, plant height, silking, lodging, grain yield, thousand-seed weight, protein content and grain commercial classification. After using analysis of variance the means were used to estimate the genetic dissimilarity among all genotypes pairs based on the Mahalanobis’ generalized distance. Cluster analysis using genetic distance matrix was performed having Unweighted Pair Group Method using Arithmetic Means method (UPGMA as the criteria. Highly significant differences were found among the genotypes for all traits evaluated. The high coefficient of genetic variation indicates the possibility of having genetic gains for all traits. The traits that most contributed to the variability were the flag leaf area and silking, while the protein content and lodging were the traits that contributed the least. Based on the cluster analysis, at least three major groups of similarity were found. There was a clustering trend of two and six-rowed materials. The most divergent genotypes were PFC 2005123, Antártica-1, Nandi and FM 404.

  8. Integrating technology education concepts into China's educational system

    Science.gov (United States)

    Yang, Faxian

    The problem of this study was to develop a strategy for integrating technology education concepts within the Chinese mathematics and science curricula. The researcher used a case study as the basic methodology. It included three methods for collecting data: literature review, field study in junior and senior secondary schools in America and China, and interviews with experienced educators who were familiar with the status of technology education programs in the selected countries. The data came from the following areas: Japan, Taiwan, the United Kingdom, China, and five states in the United States: Illinois, Iowa, Maryland, Massachusetts, and New York. The researcher summarized each state and country's educational data, identified the advantages and disadvantages of their current technology education program, and identified the major concepts within each program. The process determined that identified concepts would be readily acceptable into the current Chinese educational system. Modernization of, industry, agriculture, science and technology, and defense have been recent objectives of the Chinese government. Therefore, Chinese understanding of technology, or technology education, became important for the country. However, traditional thought and culture curb the implementation of technology education within China's current education system. The proposed solution was to integrate technology education concepts into China's mathematics and science curricula. The purpose of the integration was to put new thoughts and methods into the current educational structure. It was concluded that the proposed model and interventions would allow Chinese educators to carry out the integration into China's education system.

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

    Science.gov (United States)

    Deangelis, Maria Laura; Facoetti, Nicola

    2016-04-01

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

  10. China's numerical management system for reducing national energy intensity

    International Nuclear Information System (INIS)

    Li, Huimin; Zhao, Xiaofan; Yu, Yuqing; Wu, Tong; Qi, Ye

    2016-01-01

    In China, the national target for energy intensity reduction, when integrated with target disaggregation and information feedback systems, constitutes a numerical management system, which is a hallmark of modern governance. This paper points out the technical weaknesses of China's current numerical management system. In the process of target disaggregation, the national target cannot be fully disaggregated to local governments, sectors and enterprises without omissions. At the same time, governments at lower levels face pressure for reducing energy intensity that exceeds their respective jurisdictions. In the process of information feedback, information failure is inevitable due to statistical inaccuracy. Furthermore, the monitoring system is unable to correct all errors, and data verification plays a limited role in the examination system. To address these problems, we recommend that the government: use total energy consumption as the primary indicator of energy management; reform the accounting and reporting of energy statistics toward greater consistency, timeliness and transparency; clearly define the responsibility of the higher levels of government. - Highlights: •We assess drawbacks of China's numerical management system for energy intensity. •The national energy intensity target cannot be fully disaggregated without omissions. •Data distortion is due to failures in statistics, monitoring and examination system. •Lower-level governments’ ability to meet energy target is weaker than their pressure. •We provide three policy recommendations for China's policy-makers.

  11. Efficiency performance of China's health care delivery system.

    Science.gov (United States)

    Zhang, Luyu; Cheng, Gang; Song, Suhang; Yuan, Beibei; Zhu, Weiming; He, Li; Ma, Xiaochen; Meng, Qingyue

    2017-07-01

    Improving efficiency performance of the health care delivery system has been on the agenda for the health system reform that China initiated in 2009. This study examines the changes in efficiency performance and determinants of efficiency after the reform to provide evidence to assess the progress of the reform from the perspective of efficiency. Descriptive analysis, Data Envelopment Analysis, the Malmquist Index, and multilevel regressions are used with data from multiple sources, including the World Bank, the China Health Statistical Yearbook, and routine reports. The results indicate that over the last decade, health outcomes compared with health investment were relatively higher in China than in most other countries worldwide, and the trend was stable. The overall efficiency and total factor productivity increased after the reform, indicating that the reform was likely to have had a positive impact on the efficiency performance of the health care delivery system. However, the health care delivery structure showed low system efficiency, mainly attributed to the weakened primary health care system. Strengthening the primary health care system is central to enhancing the future performance of China's health care delivery system. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Investing in efficient industrial boiler systems in China and Vietnam

    International Nuclear Information System (INIS)

    Yang Ming; Dixon, Robert K.

    2012-01-01

    Energy efficiency in industrial boiler steam systems can be very low due to old technologies, improper design and non-optimal operation of the steam systems. Solutions include efficiency assessments and investments in steam system optimizations, education and training for operators of the systems. This paper presents case studies on assessing and investing in boiler steam systems in China and Vietnam. Methodologies and approaches for data collection and analyses were designed specifically for each of the two countries. This paper concludes: (1) investing in energy efficiency in industrial boiler steam system in China and Vietnam are cost effective; (2) government should not sent national energy efficiency standards lower than that of energy companies or energy equipment manufactures. - Highlights: ► GEF successfully catalyzed investment in industrial energy efficiency boilers in China in 1990s. ► With about $100 million of investment by the GEF/World Bank/Chinese government, the project will mitigate 40 million tons of CO 2 by 2019. ► This generated lowest unit cost of carbon reduction in the world: about $2.5 per ton of CO 2 mitigation. ► Investing in energy efficiency in industrial boiler steam system today in Vietnam will be the same cost effective as in China: $2.1 per ton of CO 2 mitigation.

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

    Science.gov (United States)

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

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

    Science.gov (United States)

    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).

  15. Evaluation of conventional, protaper hand and protaper rotary instrumentation system for apical extrusion of debris, irrigants and bacteria- An in vitro randomized trial.

    Science.gov (United States)

    Kalra, Pinky; Rao, Arathi; Suman, Ethel; Shenoy, Ramya; Suprabha, Baranya-Shrikrishna

    2017-02-01

    Endodontic instrumentation carries the risk of over extrusion of debris and bacteria. The technique used and the type of instrumentation influences this risk. The purpose of this study was to evaluate and compare the K-file, ProTaper hand and ProTaper rotary instrumentation systems for the amount of apically extruded debris, irrigant solution and intracanal bacteria. Experimental single blinded randomized type of in vitro study with sample of 30 single rooted teeth. Endodontic access cavities were prepared and the root canals were filled with the suspension of E. faecalis . Myers and Montogomery Model was used to collect apically extruded debris and irrigant. Canals were prepared using K files, Hand protapers and Protaper rotary files. Non Parametric test like Kruskal-Wallis and Mann-Whitney U test were applied to determine the significant differences among the group. Tests revealed statistically significant difference between the amount of debris and number of bacteria extruded by the ProTaper hand and the K-files. No statistically significant difference was observed between the amounts of irrigant extruded by the ProTaper hand and the K-file system. Statistically significant differences were observed between the amounts of bacteria and irrigant extruded by the ProTaper rotary and the Protaper hand. No statistically significant difference was observed between the amounts of debris extruded by the ProTaper hand and the K-file system. Amount of apical extrusion of irrigant solution, bacteria and debris are significantly greater with K File instruments and least with Protaper rotary instruments. Key words: Protaper, rotary, periapical extrusion.

  16. Crop water productivity under increasing irrigation capacities in Romania. A spatially-explicit assessment of winter wheat and maize cropping systems in the southern lowlands of the country

    Science.gov (United States)

    Dogaru, Diana

    2016-04-01

    Improved water use efficiency in agriculture is a key issue in terms of sustainable management and consumption of water resources in the context of peoples' increasing food demands and preferences, economic growth and agricultural adaptation options to climate variability and change. Crop Water Productivity (CWP), defined as the ratio of yield (or value of harvested crop) to actual evapotranspiration or as the ratio of yield (or value of harvested crop) to volume of supplied irrigation water (Molden et al., 1998), is a useful indicator in the evaluation of water use efficiency and ultimately of cropland management, particularly in the case of regions affected by or prone to drought and where irrigation application is essential for achieving expected productions. The present study investigates the productivity of water in winter wheat and maize cropping systems in the Romanian Plain (49 594 sq. km), an important agricultural region in the southern part of the country which is increasingly affected by drought and dry spells (Sandu and Mateescu, 2014). The scope of the analysis is to assess the gains and losses in CWP for the two crops, by considering increased irrigated cropland and improved fertilization, these being the most common measures potentially and already implemented by the farmers. In order to capture the effects of such measures on agricultural water use, the GIS-based EPIC crop-growth model (GEPIC) (Williams et al., 1989; Liu, 2009) was employed to simulate yields, seasonal evapotranspiration from crops and volume of irrigation water in the Romanian Plain for the 2002 - 2013 interval with focus on 2007 and 2010, two representative years for dry and wet periods, respectively. The GEPIC model operates on a daily time step, while the geospatial input datasets for this analysis (e.g. climate data, soil classes and soil parameters, land use) were harmonized at 1km resolution grid cell. The sources of the spatial data are mainly the national profile agencies

  17. Hydraulic performance of locally made LDPE-Pipes for drip irrigation systems

    International Nuclear Information System (INIS)

    Aslam, M.; Mangrio, A.G.; Ibrar, S.U.

    2007-01-01

    LDPE pipes give controlled and efficient irrigation practices for plant-water requirement. All five sizes of pipes i.e. 13.0, 25.7, 31.5, 38 and 50 mm with wall thicknesses of 1.4, 1.8, 2.0, 2.5 and 3.0 mm respectively in 100 and 200 m lengths were selected for determination of pressure-discharge relationships, manufacturing coefficient of variation and friction coefficient. The pipes were operated at pressure ranging from 10 to 50 psi (7.00 -35.00 meter head) with an increment of 5 psi. The discharge of different sizes of LDPE pipes was measured under various pressures. The average discharge of the pipes with 13.0, 25.7, 31.5, 38 and 50 mm pipe sizes between 10 to 50 psi pressure heads were 0.058, 0.301, 0.402, 0.909 and 2.076 lps respectively for 100 meter pipe length and 0.056, 0.10, 0.13, 0.45 and 1.993 lps respectively for 200 meter pipe length. The average friction head loss of the pipes with 13.0, 25.7, 31.5, 38 and 50 mm pipe sizes between 10 to 50 psi pressure heads were 3.21, 2.51, 1.66, 3.99 and 3.64 meter per 100 meter pipe length and 6.44, 5.03, 3.15, 6.79 and 6.85 meter per 200 meter pipe length respectively. The average C-value of all sizes of selected pipes for both lengths between 10-50 psi was indicated 18% less than the recommend value. Results indicated that the discharge, friction head losses and friction coefficient increased with the increase in pressure. This study helped describe the optimal pressure requirement to achieve the desirable discharge low friction head losses and minimum friction coefficients. (author)

  18. Hydrogeochemistry of high-temperature geothermal systems in China: A review

    International Nuclear Information System (INIS)

    Guo, Qinghai

    2012-01-01

    toxic elements. Since local drinking water sources may be mixed with geothermal water, and irrigation with water containing geothermally-derived harmful elements, possibly leading to accumulation in crops consumed by human beings, the natural geothermal spring discharge or anthropogenic geothermal wastewater drainage of these fields poses a threat to the environment and human health. Future research work should focus on estimation of stable O and H isotope compositions of magmatic water related to high-temperature hydrothermal systems in China, which is of significance for the quantitative source study of geothermal fluid recharged by degassed magmatic waters. Attention should also be paid to some constituent species in geothermal fluid of strong environmental significance, such as thioarsenate that is crucial for the fate of As discharged from geothermal springs, especially sulfidic hot springs.

  19. Introduction of China's Compulsory Product Certification System (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Why does China establish a new Compulso-ry Product Certification System? For a long time, our compulsory product certification system has had problems such as lack of a unified management department, repeated assessments,repeated charging and no separation between certification activities and behaviors of law enforcement.The most obvious problem is that two certification management systems exist respectively for domestic products and imported products.

  20. Comparing national infectious disease surveillance systems: China and the Netherlands.

    NARCIS (Netherlands)

    Vlieg, Willemijn L; Fanoy, Ewout B; van Asten, Liselotte; Liu, Xiaobo; Yang, Jun; Pilot, Eva; Bijkerk, Paul; van der Hoek, Wim; Krafft, Thomas; van der Sande, Marianne A; Liu, Qi-Yong

    2017-01-01

    Risk assessment and early warning (RAEW) are essential components of any infectious disease surveillance system. In light of the International Health Regulations (IHR)(2005), this study compares the organisation of RAEW in China and the Netherlands. The respective approaches towards surveillance of

  1. Comparing national infectious disease surveillance systems : China and the Netherlands

    NARCIS (Netherlands)

    Vlieg, Willemijn L; Fanoy, Ewout B; van Asten, Liselotte; Liu, Xiaobo; Yang, Jun; Pilot, Eva; Bijkerk, Paul; van der Hoek, Wim; Krafft, Thomas; van der Sande, Marianne A; Liu, Qi-Yong

    2017-01-01

    BACKGROUND: Risk assessment and early warning (RAEW) are essential components of any infectious disease surveillance system. In light of the International Health Regulations (IHR)(2005), this study compares the organisation of RAEW in China and the Netherlands. The respective approaches towards

  2. Comparative study of the primary healthcare systems in China and ...

    African Journals Online (AJOL)

    Background: Community health centres (CHCs) are an important component of the health system in Mali and China. Despite patient support and commitment from the authorities, the management and the quality of care of these structures need to be improved. This research aimed to compare the management style of the ...

  3. Nitrogen balance and groundwater nitrate contamination: Comparison among three intensive cropping systems on the North China Plain

    Energy Technology Data Exchange (ETDEWEB)

    Ju, X.T. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Kou, C.L. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Institute of Soils and Fertilizers, Henan Academy of Agricultural Sciences, Zhengzhou 450002 (China); Zhang, F.S. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China)]. E-mail: zfs@cau.edu.cn; Christie, P. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Agricultural and Environmental Science Department, Queen' s University Belfast, Belfast BT9 5PX (United Kingdom)

    2006-09-15

    The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402 kg N ha{sup -1} on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (Triticum aestivum L.)-maize (Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746 kg N ha{sup -1}, with residual soil nitrate-N after harvest amounting to 221-275, 1173 and 613 kg N ha{sup -1} in the top 90 cm of the soil profile and 213-242, 1032 and 976 kg N ha{sup -1} at 90-180 cm depth in wheat-maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (<15 m depth) was heavily contaminated in the greenhouse vegetable production area, where total N inputs were much higher than crop requirements and the excessive fertilizer N inputs were only about 40% of total N inputs. - Intensive greenhouse vegetable production systems may pose a greater nitrogen pollution threat than apple orchards or cereal rotations to soil and water quality in north China.

  4. Nitrogen balance and groundwater nitrate contamination: Comparison among three intensive cropping systems on the North China Plain

    International Nuclear Information System (INIS)

    Ju, X.T.; Kou, C.L.; Zhang, F.S.; Christie, P.

    2006-01-01

    The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402 kg N ha -1 on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (Triticum aestivum L.)-maize (Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746 kg N ha -1 , with residual soil nitrate-N after harvest amounting to 221-275, 1173 and 613 kg N ha -1 in the top 90 cm of the soil profile and 213-242, 1032 and 976 kg N ha -1 at 90-180 cm depth in wheat-maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (<15 m depth) was heavily contaminated in the greenhouse vegetable production area, where total N inputs were much higher than crop requirements and the excessive fertilizer N inputs were only about 40% of total N inputs. - Intensive greenhouse vegetable production systems may pose a greater nitrogen pollution threat than apple orchards or cereal rotations to soil and water quality in north China

  5. Health system strengthening and hypertension management in China.

    Science.gov (United States)

    Huang, Kehui; Song, Yu Ting; He, Yong Huan; Feng, Xing Lin

    2016-01-01

    Non-communicable diseases are the leading causes of global burden of diseases, and hypertension is one of the most important risk factors. Hypertension prevalence doubled in China in the past decade and affects more than 300 million Chinese people. In the review we systematically searched peer-reviewed publications that link health system level factors with hypertension management in China and provide the current knowledge on how to improve a country's health system to manage the hypertension epidemic. A framework was developed to guide the review. The database of PubMed, CNKI were systematically searched from inception to April 13, 2016. Two authors independently screened the searched results for inclusion, conducted data extraction and appraised the quality of studies. Key findings were described according to the framework. Five hundred seventy-two publications were identified, where 11 articles were left according to the inclusion and exclusion criteria. The study periods range from 2010 to 2015. All about 11 researches linked health system factors to the outcome of hypertension management. And the outcomes were just focused on the awareness, treatment and control of hypertension but not hypertension incidence. One study is about the role of health system governance, investigating the performance of different organized community health care centers; three studies were about health financing comparing differences in insurance coverage; three studies were about health information practicing the hypertension guidelines of China or the WHO, and the rest three about mechanisms of health service delivery. No researches were identified about physical resources for health and human resources for health. Hypertension prevalence has been rising rapidly in China and the management of hypertension in China is a detection problem rather than treatment problem. Limited evidence shows the positive effect of health system factors on hypertension management and joint efforts

  6. Technical descriptions of ten irrigation technologies for conserving energy

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-05-01

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

  7. Global Recession and the National System of Innovation in China

    DEFF Research Database (Denmark)

    Muchie, Mammo; Baskaran, Angethvar

    2011-01-01

    Since the early 1990s China’s economy has emerged one of the leading economies in the world using judicial mix of policies of economic liberalisation and protection. China’s national system of innovation (NSI) has been evolving and has been adapting to the challenges posed the globalisation. China...... China, which was triggered by the global credit crunch and slow down of trade. Major economies across the world have introduced a series of measures in response to recession and to stem the tide of its negative impacts. These measures included: bank bailouts, rescue packages, fiscal stimuli, and, most...... economies in the world due to the differences among their NSIs.In the case of China, to reduce the negative impacts of the global recession, it announced a fiscal stimulus package of $586b (14% of GDP) in November 2008 aimed to stimulate the domestic demand and also to boost the income of the poor...

  8. China's tax system relatively benign, but problems remain

    International Nuclear Information System (INIS)

    Cannon, M.

    1994-01-01

    Recent developments in China's oil market have reignited the interest of multinational oil and gas companies in China. New onshore and offshore blocks are being granted, and the Tarim basin has been opened to foreign participation for the first time. Foreign participation is also being sought in refining and other downstream areas. Though Chinese officials have long been viewed as difficult negotiators, the tax provisions applicable to oil and gas exploration and production in China are some of the more generous in the area. This article describes some of the relevant features of the system and some of the problem areas. The paper describes production sharing contracts, applicable taxes, gross income determination, taxable income, tax consolidation, overseas charges, and withholding taxes on payments to subcontractors and employees

  9. Using SWAT-MODFLOW to simulate groundwater flow and groundwater-surface water interactions in an intensively irrigated stream-aquifer system

    Science.gov (United States)

    Wei, X.; Bailey, R. T.

    2017-12-01

    Agricultural irrigated watersheds in semi-arid regions face challenges such as waterlogging, high soil salinity, reduced crop yield, and leaching of chemical species due to extreme shallow water tables resulting from long-term intensive irrigation. Hydrologic models can be used to evaluate the impact of land management practices on water yields and groundwater-surface water interactions in such regions. In this study, the newly developed SWAT-MODFLOW, a coupled surface/subsurface hydrologic model, is applied to a 950 km2 watershed in the Lower Arkansas River Valley (southeastern Colorado). The model accounts for the influence of canal diversions, irrigation applications, groundwater pumping, and earth canal seepage losses. The model provides a detailed description of surface and subsurface flow processes, thereby enabling detailed description of watershed processes such as runoff, infiltration, in-streamflow, three-dimensional groundwater flow in a heterogeneous aquifer system with sources and sinks (e.g. pumping, seepage to subsurface drains), and spatially-variable surface and groundwater exchange. The model was calibrated and tested against stream discharge from 5 stream gauges in the Arkansas River and its tributaries, groundwater levels from 70 observation wells, and evapotranspiration (ET) data estimated from satellite (ReSET) data during the 1999 to 2007 period. Since the water-use patterns within the study area are typical of many other irrigated river valleys in the United States and elsewhere, this modeling approach is transferable to other regions.

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

    Science.gov (United States)

    Mozo, Sandra; Llena, Carmen

    2012-01-01

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

  11. Le devenir de la gestion traditionnelle des eaux apres l'envahissement des systemes modernes d'irrigation. Oasis de Boukais, Sud-Ouest algérien

    OpenAIRE

    CHERIF REZZOUG; BOUALEM REMINI; SAAD HAMOUDI

    2014-01-01

    The evolution of traditional water administration after the extension of modern irrigation systems. Oasis de Boukais, south - west of Algeria. One of the topics that touch the field of environment is undoubtedly the traditional catchment systems and the sharing of water in the oasis. The ancestral techniques such as wells to chadouf, quanat, Khettara and foggaras have protected the oasis and the man in the past. These t...

  12. Modelling human agency in ancient irrigation

    NARCIS (Netherlands)

    Ertsen, M.W.

    2011-01-01

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

  13. Two Case Studies to Quantify Resilience across Food-Energy-Water Systems: the Columbia River Treaty and Adaptation in Yakima River Basin Irrigation Systems

    Science.gov (United States)

    Malek, K.; Adam, J. C.; Richey, A.; Rushi, B. R.; Stockle, C.; Yoder, J.; Barik, M.; Lee, S. Y.; Rajagopalan, K.; Brady, M.; Barber, M. E.; Boll, J.; Padowski, J.

    2017-12-01

    The U.S. Pacific Northwest (PNW) plays a significant role in meeting agricultural and hydroelectric demands nationwide. Climatic and anthropogenic stressors, however, potentially threaten the productivity, resilience, and environmental health of the region. Our objective is to understand how resilience of each Food-Energy-Water (FEW) sector, and the combined Nexus, respond to exogenous perturbations and the extent to which technological and institutional advances can buffer these perturbations. In the process of taking information from complex integrated models and assessing resilience across FEW sectors, we start with two case studies: 1) Columbia River Treaty (CRT) with Canada that determines how multiple reservoirs in the Columbia River basin (CRB) are operated, and 2) climate change adaptation actions in the Yakima River basin (YRB). We discuss these case studies in terms of the similarities and contrasts related to FEW sectors and management complexities. Both the CRB and YBP systems are highly sensitive to climate change (they are both snowmelt-dominant) and already experience water conflict. The CRT is currently undergoing renegotiation; a new CRT will need to consider a much more comprehensive approach, e.g., treating environmental flows explicitly. The YRB also already experiences significant water conflict and thus the comprehensive Yakima Basin Integrated Plan (YBIP) is being pursued. We apply a new modeling framework that mechanistically captures the interactions between the FEW sectors to quantify the impacts of CRT and YBIP planning (as well as adaptation decisions taken by individuals, e.g., irrigators) on resilience in each sector. Proposed modification to the CRT may relieve impacts to multiple sectors. However, in the YRB, irrigators' actions to adapt to climate change (through investing in more efficient irrigation technology) could reduce downstream water availability for other users. Developing a process to quantify resilience to perturbations

  14. The effect of irrigation, soil cultivation system and nitrogen fertilizer on the vitality and content of selected sugars in Vicia faba seed

    Energy Technology Data Exchange (ETDEWEB)

    Kurasiak-Popowska, D.; Szukala, J.; Gulewicz, K.

    2009-07-01

    In this study the influence of sprinkler irrigation, various soil cultivation systems (conventional, reduced tillage, zero tillage system) and the level (0, 30, 60, 90 kg N ha{sup -}1) of nitrogen (N) fertilization on the vitality and content of selected sugars in faba bean seeds (Vicia faba L.) of the cultivar Nadwislanski was examined. Sprinkler irrigation of faba bean improved seed energy and germination in all three years of the study (1999-2001) - on average germination energy by 8.8% and total germination by 3.2%-. Germination of faba bean seed under conventional tillage in the drier years was significantly higher than in the zero tillage system. In the wetter year, seed from both simplified systems produced seeds with higher germination than in traditional conventional tillage. Nitrogen (N) fertilizer affected germination energy, but had no effect on faba bean germination. Sprinkler irrigation and N fertilization had no effect on the content of the sugars studied in the faba bean seed. However, the stachyose content of faba bean seeds from conventional tilled plants was significantly higher than in seed of zero tilled plants (0.78 mg g{sup -}1 seed dm), and the galactose content of seed from zero tilled plants was significantly higher than in the other two cultivation systems - 0.34 and 0.28 mg g{sup -}1 seed dm in seeds from conventional and reduced tillage system, respectively. Additional key words: agronomic treatment, faba bean seeds, RFOs sugars. (Author) 24 refs.

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  16. Modeling Acequia Irrigation Systems Using System Dynamics: Model Development, Evaluation, and Sensitivity Analyses to Investigate Effects of Socio-Economic and Biophysical Feedbacks

    Directory of Open Access Journals (Sweden)

    Benjamin L. Turner

    2016-10-01

    Full Text Available Agriculture-based irrigation communities of northern New Mexico have survived for centuries despite the arid environment in which they reside. These irrigation communities are threatened by regional population growth, urbanization, a changing demographic profile, economic development, climate change, and other factors. Within this context, we investigated the extent to which community resource management practices centering on shared resources (e.g., water for agricultural in the floodplains and grazing resources in the uplands and mutualism (i.e., shared responsibility of local residents to maintaining traditional irrigation policies and upholding cultural and spiritual observances embedded within the community structure influence acequia function. We used a system dynamics modeling approach as an interdisciplinary platform to integrate these systems, specifically the relationship between community structure and resource management. In this paper we describe the background and context of acequia communities in northern New Mexico and the challenges they face. We formulate a Dynamic Hypothesis capturing the endogenous feedbacks driving acequia community vitality. Development of the model centered on major stock-and-flow components, including linkages for hydrology, ecology, community, and economics. Calibration metrics were used for model evaluation, including statistical correlation of observed and predicted values and Theil inequality statistics. Results indicated that the model reproduced trends exhibited by the observed system. Sensitivity analyses of socio-cultural processes identified absentee decisions, cumulative income effect on time in agriculture, and land use preference due to time allocation, community demographic effect, effect of employment on participation, and farm size effect as key determinants of system behavior and response. Sensitivity analyses of biophysical parameters revealed that several key parameters (e.g., acres per

  17. An economic analysis of the political promotion system in China

    OpenAIRE

    Jiancai Pi

    2017-01-01

    This paper mainly discusses the political promotion system in China. Specifically, we develop a generalized analytical framework by introducing the contest success function. On the one hand, the central government can give the optimal political promotion benefits to local officials to incentivize them to exert desirable developmental efforts. On the other hand, the central government can undertake a further design of the political promotion system to motivate local officials vi...

  18. China's rural energy system and management

    International Nuclear Information System (INIS)

    Catania, Peter

    1999-01-01

    The issues related to rural energy development and the corresponding escalating economic activities have given rise to a complex, interrelationship among societal, economics, energy, environment and rural policies. With 7% of the world's farm land to produce food for 23% of the world's population, combined with the increasing energy demands for modernised farming has resulted in a dynamic rural energy policy for China. This paper discusses the characteristics of a rural society, outlines the relationship for rural energy supply and demand management, and discusses the interrelationship between energy and the environment utilisation. An illustration of the diffusion of biomass as a success story highlights some of the policies related to self-building, self-managing and self-using. Also discussed in this paper are the results of the integrated rural energy-policy, that is, the social benefits to farmers and the decrease of energy consumption per unit of output. Emerging nations must undertake a comprehensive analysis and synthesis of their respective rural energy developments and the corresponding interrelationships between technology, economics and the environment. (Author)

  19. to Irrigation Intervals and Plant Density in Zuru, Northern Guinea

    African Journals Online (AJOL)

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

  20. Low Cost Constant – Head Drip Irrigation Emitter for Climate ...

    African Journals Online (AJOL)

    Low Cost Constant – Head Drip Irrigation Emitter for Climate Change Adaptation in Nigeria: Engineering Design and Calibration. ... The drip system comprises of abarrel, sub-main line, lateral lines, tubes and emitters, it can irrigate140 crop ...

  1. Is the Revitalisation of Smallholder Irrigation Schemes (RESIS ...

    African Journals Online (AJOL)

    2013-09-30

    Sep 30, 2013 ... including rainwater harvesting, flood recession, flood water spreading, river ... Smallholder irrigation systems can comprise farmers who use shared or ...... on Irrigation and Drainage, 15-17 November 2006, Aventura. Swadini.

  2. Economic Analysis of Crop Production under Jibiya Irrigation Project ...

    African Journals Online (AJOL)

    Majority of the farmers were married and can read and write. Most of ... The performance of the farmers, though ... holder irrigation dependent on the shadoof system of lifting water as .... implies that in Jibiya Irrigation Project, women were not.

  3. Challenges to China's transition to a low carbon electricity system

    International Nuclear Information System (INIS)

    Kahrl, Fredrich; Williams, Jim; Ding Jianhua; Hu Junfeng

    2011-01-01

    We examine the challenges to China's transition to a low carbon electricity system, in which renewable energy would play a significant role. China's electricity system currently lacks the flexibility in planning, operations, and pricing to respond to conflicting pressures from demand growth, rising costs, and environmental mandates in a way that simultaneously maintains reliability, decarbonizes the system, and keeps prices within acceptable bounds. Greater flexibility crucially requires the ability to more systematically and transparently manage and allocate costs. This will require re-orientating sector institutions still rooted in central planning, and strengthening independent regulation. Some of the necessary changes require fundamental political and legal reforms beyond the scope of energy policy. However, the system's flexibility can still be increased through the development of traditional planning and regulatory tools and approaches, such as an avoided cost basis for energy efficiency investments, more integrated planning to improve the coordination of generation, transmission, and demand-side investments, and a transparent ratemaking process. The judicious application of OECD electricity sector experience and skills can support these developments. - Research highlights: → China's electricity system currently lacks the flexibility to integrate renewables and reduce CO 2 emissions on a large scale at an acceptable cost and level of reliability. → The challenges to increased flexibility are more institutional than technological. → Chinese government agencies need new approaches to basic power system planning and ratemaking. → OECD countries can help address these challenges through the transfer of 'soft' technologies.

  4. Nitrous oxide emissions from an intensively managed greenhouse vegetable cropping system in Northern China

    International Nuclear Information System (INIS)

    He Feifei; Jiang Rongfeng; Chen Qing; Zhang Fusuo; Su Fang

    2009-01-01

    Nitrous oxide (N 2 O) emissions from a typical greenhouse vegetable system in Northern China were measured from February 2004 to January 2006 using a close chamber method. Four nitrogen management levels (NN, MN, CN, and SN) were used. N 2 O emissions occurred intermittently in the growing season, strongly correlating with N fertilization and irrigation. No peak emissions were observed after fertilization in the late Autumn season due to low soil temperature. 57-94% of the seasonal N 2 O emissions came from the initial growth stage, corresponding to the rewetting process in the soil. The annual N 2 O emissions ranged from 2.6 to 8.8 kg N ha -1 yr -1 , accounting for 0.27-0.30% of the annual nitrogen input. Compared with conventional N management, site-specific N management reduced N fertilization rate by 69% in 2004 and by 76% in 2005, and consequently reduced N 2 O emissions by 51% in 2004 and 27% in 2005, respectively. - High N 2 O emissions coming from the initial growth stage can be attributed to the rewetting process in the greenhouse soil.

  5. Cierny-Mader Type III chronic osteomyelitis: the results of patients treated with debridement, irrigation, vancomycin beads and systemic antibiotics

    Science.gov (United States)

    Karaduman, Mert

    2007-01-01

    Cierny-Mader (C-M) Type III osteomyelitis is defined as a localised lesion with both medullary and cortical involvement that is stable mechanically after debridement. The treatment of C-M Type III osteomyelitisis is difficult and requires a precise protocol to achieve a disease-free long-term follow-up. We report here the results of our study on 26 patients (19 men and 7 women; average age: 34.7 years) with C-M Type III osteomylelitis who were treated with radical debridement, irrigation, vancomycin-impregnated custom-made beads and culture-specific systemic antibiotics. Those patients with metaphyseal involvement were treated with deroofing of the cortex and debridement by means of a “trough” (16 patients); those with diaphyseal involvement were treated with both intramedullary reaming and debridement from a trough (ten patients). Antibiotic cement rods were used as an additional therapy in five patients with diaphyseal involvement. Recurrence developed in three patients and was attributed to inadequate debridement; all three patients were treated again in the same manner with success. The mean follow-up is currently 3.6 years (range: 2–6 years). All of the patients have normal clinical, radiographic and laboratory parameters, and all are ambulatory and have returned to their pretreatment level of activity or better. We conclude that C-M Type III chronic osteomyelitis can be safely treated with this protocol. PMID:17375299

  6. Analysis of Barriers against Wheat Farmers' Participation in the Formation of Water Users Association: the Case of Dez Irrigation System

    Directory of Open Access Journals (Sweden)

    ali pazhuhan

    2016-11-01

    The present study was aimed at analyzing the barriers against wheat farmers' participation in the formation of water users association within the framework of a descriptive survey. The sample of this study included 375 wheat farmers in Dez irrigation system who were selected through random cluster sampling and were studied through a questionnaire. The reliability index of this questionnaire was estimated to be 0.89. The content validity of the questionnaire was confirmed by the experts and scholars in the field. After the participants filled the questionnaires and the data were collected, the SPSS software package was used to analyze the data. In addition, the results of factor analysis related to the items of barriers led to the extraction of four barriers. These barriers, in order of importance, include the lack of proper infrastructures and economic facilities, social barriers, inadequate structural characteristics and lack of risk-taking, local organizations and lack of attention to extension activities that explain 60.78 percent of the variance of all the barriers.

  7. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    Science.gov (United States)

    Zaib Jadoon, Khan; Umer Altaf, Muhammad; McCabe, Matthew Francis; Hoteit, Ibrahim; Muhammad, Nisar; Moghadas, Davood; Weihermüller, Lutz

    2017-10-01

    A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  8. Technical- and environmental-efficiency analysis of irrigated cotton-cropping systems in Punjab, Pakistan using data envelopment analysis.

    Science.gov (United States)

    Ullah, Asmat; Perret, Sylvain R

    2014-08-01

    Cotton cropping in Pakistan uses substantial quantities of resources and adversely affects the environment with pollutants from the inputs, particularly pesticides. A question remains regarding to what extent the reduction of such environmental impact is possible without compromising the farmers' income. This paper investigates the environmental, technical, and economic performances of selected irrigated cotton-cropping systems in Punjab to quantify the sustainability of cotton farming and reveal options for improvement. Using mostly primary data, our study quantifies the technical, cost, and environmental efficiencies of different farm sizes. A set of indicators has been computed to reflect these three domains of efficiency using the data envelopment analysis technique. The results indicate that farmers are broadly environmentally inefficient; which primarily results from poor technical inefficiency. Based on an improved input mix, the average potential environmental impact reduction for small, medium, and large farms is 9, 13, and 11 %, respectively, without compromising the economic return. Moreover, the differences in technical, cost, and environmental efficiencies between small and medium and small and large farm sizes were statistically significant. The second-stage regression analysis identifies that the entire farm size significantly affects the efficiencies, whereas exposure to extension and training has positive effects, and the sowing methods significantly affect the technical and environmental efficiencies. Paradoxically, the formal education level is determined to affect the efficiencies negatively. This paper discusses policy interventions that can improve the technical efficiency to ultimately increase the environmental efficiency and reduce the farmers' operating costs.

  9. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    Directory of Open Access Journals (Sweden)

    K. Z. Jadoon

    2017-10-01

    Full Text Available A substantial interpretation of electromagnetic induction (EMI measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  10. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    KAUST Repository

    Jadoon, Khan Zaib

    2017-10-26

    A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes\\' rule. The electromagnetic forward model based on the full solution of Maxwell\\'s equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

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

    Science.gov (United States)

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

    2011-01-01

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

  12. Heavy metal input to agricultural soils from irrigation with treated wastewater: Insight from Pb isotopes

    Science.gov (United States)

    Kloppmann, Wolfram; Cary, Lise; Psarras, Georgios; Surdyk, Nicolas; Chartzoulakis, Kostas; Pettenati, Marie; Maton, Laure

    2010-05-01

    A major objective of the EU FP6 project SAFIR was to overcome certain drawbacks of wastewater reuse through the development of a new irrigation technology combining small-scale modular water treatment plants on farm level and improved irrigation hardware, in the aim to lower the risks related to low quality water and to increase water use efficiency. This innovative technology was tested in several hydro-climatic contexts (Crete, Italy, Serbia, China) on experimental irrigated tomato and potato fields. Here we present the heavy metal variations in soil after medium-term (3 irrigation seasons from 2006-2008) use of treated municipal wastewater with a special focus on lead and lead isotope signatures. The experimental site is located in Chania, Crete. A matrix of plots were irrigated, combining different water qualities (secondary, primary treated wastewater, tap water, partially spiked with heavy metals, going through newly developed tertiary treatment systems) with different irrigation strategies (surface and subsurface drip irrigation combined with full irrigation and partial root drying). In order to assess small scale heavy metal distribution around a drip emitter, Pb isotope tracing was used, combined with selective extraction. The sampling for Pb isotope fingerprinting was performed after the 3rd season of ww-irrigation on a lateral profile from a drip irrigator (half distance between drip lines, i.e. 50cm) and three depth intervals (0-10, 10-20, 20-40 cm). These samples were lixiviated through a 3 step selective extraction procedure giving rise to the bio-accessible, mobile and residual fraction: CaCl2/NaNO3 (bio-accessible fraction), DPTA (mobile fraction), total acid attack (residual fraction). Those samples were analysed for trace elements (including heavy metals) and major inorganic compounds by ICP-MS. The extracted fractions were then analysed by Thermal Ionisation Mass Spectrometry (TIMS) for their lead isotope fingerprints (204Pb, 206Pb, 207Pb, 208Pb

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

    Science.gov (United States)

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

  14. Limited irrigation research and infrared thermometry for detecting water stress

    Science.gov (United States)

    The USDA-ARS Limited Irrigation Research Farm, located outside of Greeley Colorado, is an experiment evaluating management perspectives of limited irrigation water. An overview of the farm systems is shown, including drip irrigation systems, water budgeting, and experimental design, as well as preli...

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

    African Journals Online (AJOL)

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

  16. Ghana - Agriculture - Irrigation

    Data.gov (United States)

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

  17. Solar and wind systems utilization in water pumping for irrigation; Utilizacao de sistemas solar e eolico no bombeamento de agua para uso na irrigacao

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Cicero Urbanetto

    2009-07-01

    In this work, it was made an applied research in two stations, the first one located at Canabarro locality and the second one at Polytechnic School at UFSM, in Santa Maria city, RS, with wind and photovoltaic equipment for pumping water. These ones are used for fruit trees irrigation in irrigation systems of low pressure. The research work was developed from September 2007 to August 2009, when the results showed the viability of wind and photovoltaic equipment for utilization in the complementary irrigation in fruit cultures such as guava, fig and grape trees. In the fruit culture sector, are installed: one multivane fans wind indicator one savonius wind indicator and respective pumps as well as pump set and a photovoltaic board. With the photovoltaic system, the pumped volume was about 5000 m{sup 3}/ha and, with the wind system, the pumped volume was approximately 6m{sup 3}/ha. The wind groups demonstrated low efficiency, if compared to photovoltaic systems, which showed more efficient. (author)

  18. On a State-Sponsored Sport System in China.

    Science.gov (United States)

    Cao, Jie; Zhiwei, Pan

    The gold medal success of China in recent Olympic Games can be traced to the advancement of the state-sponsored sport system (SSSS). While the program was developed initially through socialist ideals, it is more than a centralized government system to monopolize resources for glorified sport performance. Participation in competition is an inherent part of the human condition. Success in athletics is associated with national identity and has economic, social, and cultural implications. Because of this, it is essential that the SSSS adjust and improve to keep pace with other facets of China's quickly changing national reform. In association with emerging economic reform, some sports now receive equal or more funds from private investments compared to government allocation. The state-sponsored sport system must continue to adapt to maintain the Chinese tradition of excellence in competition.

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

    Science.gov (United States)

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

    2014-05-01

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

  20. Introduction of filtration systems in container nurseries for nonchemical elimination of Phytophthora spp. from irrigation water

    Science.gov (United States)

    Thorsten Ufer; Heinrich Beltz; Thomas Brand; Katrin Kaminski; Ralf Lüttmann; Martin Posner; Stefan Wagner; Sabine Werres; Hans-Peter Wessels

    2006-01-01

    In a 3-year project the elimination of Phytophthora spp. from the recirculation water with different kinds of filtration systems will be tested under commercial conditions in container nurseries. First results indicate that the filtration systems eliminate Phytophthora spp. from the water.

  1. Root canal irrigants

    OpenAIRE

    Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

    2010-01-01

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

  2. Evaluation of conventional, protaper hand and protaper rotary instrumentation system for apical extrusion of debris, irrigants and bacteria- An in vitro randomized trial

    OpenAIRE

    Kalra, Pinky; Rao, Arathi; Suman, Ethel; Shenoy, Ramya; Suprabha, Baranya-Shrikrishna

    2017-01-01

    Background Endodontic instrumentation carries the risk of over extrusion of debris and bacteria. The technique used and the type of instrumentation influences this risk. Aim The purpose of this study was to evaluate and compare the K-file, ProTaper hand and ProTaper rotary instrumentation systems for the amount of apically extruded debris, irrigant solution and intracanal bacteria. Design Experimental single blinded randomized type of in vitro study with sample of 30 single rooted teeth. Endo...

  3. Challenges in legislation, recycling system and technical system of waste electrical and electronic equipment in China.

    Science.gov (United States)

    Zhang, Shengen; Ding, Yunji; Liu, Bo; Pan, De'an; Chang, Chein-chi; Volinsky, Alex A

    2015-11-01

    Waste electrical and electronic equipment (WEEE) has been one of the fastest growing waste streams worldwide. Effective and efficient management and treatment of WEEE has become a global problem. As one of the world's largest electronic products manufacturing and consumption countries, China plays a key role in the material life cycle of electrical and electronic equipment. Over the past 20 years, China has made a great effort to improve WEEE recycling. Centered on the legal, recycling and technical systems, this paper reviews the progresses of WEEE recycling in China. An integrated recycling system is proposed to realize WEEE high recycling rate for future WEEE recycling. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Evaluation of hazardous metal pollution in irrigation and drinking water systems in the vicinity of a coal mine area of northwestern Bangladesh.

    Science.gov (United States)

    Bhuiyan, Mohammad A H; Islam, M A; Dampare, Samuel B; Parvez, Lutfar; Suzuki, Shigeyuki

    2010-07-15

    An integrated approach of pollution evaluation indices, principal component analysis (PCA) and cluster analysis (CA) was employed to evaluate the intensity and sources of pollution in irrigation and drinking water systems of northwestern Bangladesh. Temperature, BOD, chemical oxygen demand (COD), Mn, Fe, Co, Ni, Cu and Pb levels in most of the water samples exceed the Bangladesh and international standards. The heavy metal pollution index (HPI) and degree of contamination (C(d)) yield different results despite significant correlations between them. The heavy metal evaluation index (HEI) shows strong correlations with HPI and C(d), and gives a better assessment of pollution levels. Modifications to the existing HPI and C(d) schemes show comparable results with HEI, and indicate that about 55% of the mine drainage/irrigation waters and 50% of the groundwaters are moderately to highly contaminated. The CA, PCA and pollution indices suggest that the mine drainage water (DW) is contaminated by anthropogenic (mining operation and agrogenic) sources, and the proximal parts are more contaminated than the distal part. The groundwater system in the vicinity of the coal mine site is also heavily polluted by anthropogenic sources. The pollution status of irrigation and drinking water systems in the study area are of great environmental and health concerns. 2010 Elsevier B.V. All rights reserved.

  5. Comparing national infectious disease surveillance systems: China and the Netherlands.

    Science.gov (United States)

    Vlieg, Willemijn L; Fanoy, Ewout B; van Asten, Liselotte; Liu, Xiaobo; Yang, Jun; Pilot, Eva; Bijkerk, Paul; van der Hoek, Wim; Krafft, Thomas; van der Sande, Marianne A; Liu, Qi-Yong

    2017-05-08

    Risk assessment and early warning (RAEW) are essential components of any infectious disease surveillance system. In light of the International Health Regulations (IHR)(2005), this study compares the organisation of RAEW in China and the Netherlands. The respective approaches towards surveillance of arboviral disease and unexplained pneumonia were analysed to gain a better understanding of the RAEW mode of operation. This study may be used to explore options for further strengthening of global collaboration and timely detection and surveillance of infectious disease outbreaks. A qualitative study design was used, combining data retrieved from the literature and from semi-structured interviews with Chinese (5 national-level and 6 provincial-level) and Dutch (5 national-level) experts. The results show that some differences exist such as in the use of automated electronic components of the early warning system in China ('CIDARS'), compared to a more limited automated component in the Netherlands ('barometer'). Moreover, RAEW units in the Netherlands focus exclusively on infectious diseases, while China has a broader 'all hazard' approach (including for example chemical incidents). In the Netherlands, veterinary specialists take part at the RAEW meetings, to enable a structured exchange/assessment of zoonotic signals. Despite these differences, the main conclusion is that for the two infections studied, the early warning system in China and the Netherlands are remarkably similar considering their large differences in infectious disease history, population size and geographical setting. Our main recommendations are continued emphasis on international corporation that requires insight into national infectious disease surveillance systems, the usage of a One Health approach in infectious disease surveillance, and further exploration/strengthening of a combined syndromic and laboratory surveillance system.

  6. Syringe irrigation: blending endodontics and fluid dynamics

    NARCIS (Netherlands)

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

    2015-01-01

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

  7. Current trauma care system and trauma care training in China

    Directory of Open Access Journals (Sweden)

    Lian-Yang Zhang

    2018-04-01

    Full Text Available Trauma is a life-threatening “modern disease”. The outcomes could only be optimized by cost-efficient and prompt trauma care, which embarks on the improvement of essential capacities and conceptual revolution in addition to the disruptive innovation of the trauma care system. According to experiences from the developed countries, systematic trauma care training is the cornerstone of the generalization and the improvement on the trauma care, such as the Advance Trauma Life Support (ATLS. Currently, the pre-hospital emergency medical services (EMS has been one of the essential elements of infrastructure of health services in China, which is also fundamental to the trauma care system. Hereby, the China Trauma Care Training (CTCT with independent intellectual property rights has been initiated and launched by the Chinese Trauma Surgeon Association to extend the up-to-date concepts and techniques in the field of trauma care as well to reinforce the generally well-accepted standardized protocols in the practices. This article reviews the current status of the trauma care system as well as the trauma care training. Keywords: Trauma care system, Trauma care training, China

  8. Use of 15N methodology to assess urea use efficiency under different nitrogen levels in fertigation system and comparison with furrow irrigation on tomato

    International Nuclear Information System (INIS)

    Mousavi Shalmani, M. A.; Sagheb, N.; Hobbi, M.S.; Teimoori, S.; Khorasani, A.; Piervali, N.

    2003-01-01

    In order to determine a suitable level of nitrogen fertilizer for simultaneous increasing the nitrogen fertilizer use efficiency and the yield production under the trickle fertigation system in comparison with the furrow irrigation, an experimental design was conducted in a randomized complete block with five treatments and four replications in plots of 35 square meters area. The treatments of N 0 , N 1 , N 2 and N 3 received 0, 100, 150 and 200 mg N/lit, respectively under the trickle fertigation, and for the treatment of Ns the amount of fertilizer were equal to N 2 but under the furrow irrigation system. Fertilization and irrigation were performed by means of two fertigator pumps (one for urea and the other for ammonium phosphate and potassium sulfate) . In order to determine the nitrogen fertilizer use efficiency, six plants in the middle of each plot received 15 N labeled urea (isotopic form of 14 N) through plastic containers. Irrigation schedule and soil moisture monitoring were performed by means of a neutron gauge. The results showed that in spite of increasing the nitrogen levels in the fertigation system, the nitrogen fertilizer use efficiency decreases. In this respect, the treatment of N 1 could absorb %54 of nitrogen fertilizer which indicated that the highest fertilizer use efficiency under the current design condition and the final nitrogen fertilizer use efficiency for N 2 and N 3 treatments are %39 and %31, respectively. In addition, the traditional treatment (Ns), with %83 losses of nitrogen had the lowest rate of fertilizer use efficiency

  9. Problems of Participation and Issues of Sustainability in the Public Irrigation System in the Context of Management Transfer: Some Sociological Observations from Eastern Terai, Nepal

    Directory of Open Access Journals (Sweden)

    Laya Prasad Uprety

    2011-04-01

    Full Text Available It has been ascertained that participatory processes did not involve learning component from both agency and water users’ association for institutional and technical sustainability. The overall process of participation was superficial. There was a need of participation that underscored the empowerment of WUA with accountability. As Vermillion (2005 shares that empowerment with partnership is an emergent institutional paradigm for the irrigation sector development that places water users in the role of irrigation system governance, and government in the roles of regulator and provider of support services. There is a need to re-train the irrigation staff on the emergent institutional paradigm to empower the water users. For the empowerment with accountability, water users are to be provided enough institutional strengthening. There is the need to promote user-agency relationship positively and develop faith and confidence of the users and agency in the regime of transparency. Social scientists point out potential benefits of building successful local organizations. These benefits, for the local people, are in aspects such as empowerment, confidence-building, forming social capital, and reduction of dependency. Given the fact that participation is a process, it cannot be achieved in a short span of time with little institutional inputs. Sustainability of the management transferred irrigation systems/sub-systems definitely hinges on the broad-based and inclusive participatory processes. Keywords: participation; sustainability; management transfer; social capital and empowerment DOI: 10.3126/dsaj.v4i0.4512 Dhaulagiri Journal of Sociology and Anthropology Vol.4 2010 pp.41-64

  10. An Integrated Modeling System for Water Resource Management Under Climate Change, Socio-Economic Development and Irrigation Management

    Science.gov (United States)

    SU, Q.; Karthikeyan, R.; Lin, Y.

    2017-12-01

    Water resources across the world have been increasingly stressed in the past few decades due to the population and economic growth and climate change. Consequently, the competing use of water among agricultural, domestic and industrial sectors is expected to be increasing. In this study, the water stresses under various climate change, socio-economic development and irrigation management scenarios are predicted over the period of 2015-2050 using an integrated model, in which the changes in water supply and demand induced by climate change, socio-economic development and irrigation management are dynamically parameterized. Simulations on the case of Texas, Southwest U.S. were performed using the newly developed integrated model, showing that the water stress is projected to be elevated in 2050 over most areas of Texas, particularly at Northern and Southern Plain and metropolitan areas. Climate change represents the most pronounce factor affecting the water supply and irrigation water demand in Texas. The water supply over East Texas is largely reduced in future because of the less precipitation and higher temperature under the climate change scenario, resulting in an elevated irrigation water demand and thus a higher water stress in this region. In contrast, the severity of water shortage in West Texas would be alleviated in future because of climate change. The water shortage index over metropolitan areas would increase by 50-90% under 1.0% migration scenario, suggesting that the population growth in future could also greatly stress the water supply, especially megacities like Dallas, Houston, Austin and San Antonio. The projected increase in manufacturing water demand shows little effects on the water stress. Increasing irrigation rate exacerbates the water stress over irrigated agricultural areas of Texas.

  11. Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds

    Science.gov (United States)

    A long-term systems trial was established to evaluate management practices for organic production of northern highbush blueberry (Vaccinium corymbosum L.). The factorial experiment included two planting bed treatments (flat and raised beds), source and rate of fertilizer (feather meal and fish emuls...

  12. Endogenous enforcement and effectiveness of China's pollution levy system

    OpenAIRE

    Hua Wang; Wheeler, David

    2000-01-01

    The authors investigate two aspects of China's pollution levy system, which was first implemented about 20 years ago. First, they analyze what determines differences in enforcement of the pollution levy in various urban areas. They find that collection of the otherwise uniform pollution levy is sensitive to differences in economic development and environmental quality. Air and water pollution levies are higher in areas that are heavily polluted. Second, they analyze the impact of pollution ch...

  13. China

    International Nuclear Information System (INIS)

    Segal, G.

    1991-01-01

    This paper reports on the reason for China's future nuclear policy. First, assuming a continued decline in superpower influence, China's focus will be on regional issues. The policies of Japan, the NICs and other Chinese neighbors will be more relevant than those of the superpowers. Second, Chinese domestic politics will have to resume the road to reform. A more unstable and suspicious Chinese leadership will perceive a more hostile and unstable world. Even when China was on the path to reform, its foreign relations were not always peaceful. However, it would be wrong to suggest that even a more xenophobic and unstable Chinese leadership would necessarily expand China's nuclear capability or lead China into a major war. Even at the height of the Cultural Revolution, Chinese foreign policy was careful, nuclear proliferation was avoided and crises were well-managed. Still China's basic domestic and foreign policy needs will likely remain unfulfilled for the foreseeable future. Furthermore, although the East Asian balance of power may not appear to be particularly dangerous at present, there is enough uncertainty to ensure that China remains a nuclear power and a maverick one at that at least in the near term

  14. Effects of adjusting cropping systems on utilization efficiency of climatic resources in Northeast China under future climate scenarios

    Science.gov (United States)

    Guo, Jianping; Zhao, Junfang; Xu, Yanhong; Chu, Zheng; Mu, Jia; Zhao, Qian

    Quantitatively evaluating the effects of adjusting cropping systems on the utilization efficiency of climatic resources under climate change is an important task for assessing food security in China. To understand these effects, we used daily climate variables obtained from the regional climate model RegCM3 from 1981 to 2100 under the A1B scenario and crop observations from 53 agro-meteorological experimental stations from 1981 to 2010 in Northeast China. Three one-grade zones of cropping systems were divided by heat, water, topography and crop-type, including the semi-arid areas of the northeast and northwest (III), the one crop area of warm-cool plants in semi-humid plain or hilly regions of the northeast (IV), and the two crop area in irrigated farmland in the Huanghuaihai Plain (VI). An agro-ecological zone model was used to calculate climatic potential productivities. The effects of adjusting cropping systems on climate resource utilization in Northeast China under the A1B scenario were assessed. The results indicated that from 1981 to 2100 in the III, IV and VI areas, the planting boundaries of different cropping systems in Northeast China obviously shifted toward the north and the east based on comprehensively considering the heat and precipitation resources. However, due to high temperature stress, the climatic potential productivity of spring maize was reduced in the future. Therefore, adjusting the cropping system is an effective way to improve the climatic potential productivity and climate resource utilization. Replacing the one crop in one year model (spring maize) by the two crops in one year model (winter wheat and summer maize) significantly increased the total climatic potential productivity and average utilization efficiencies. During the periods of 2011-2040, 2041-2070 and 2071-2100, the average total climatic potential productivities of winter wheat and summer maize increased by 9.36%, 11.88% and 12.13% compared to that of spring maize

  15. Improved decision-making on irrigation farming in arid zones using a system dynamics model

    Directory of Open Access Journals (Sweden)

    Martin de Wit

    2013-11-01

    Full Text Available The Sandveld region in the Western Cape is a low rainfall area dominated by agricultural production using groundwater resources. The rise in agricultural production in the Sandveld has led to questions regarding the region's ecological sustainability. We developed a system dynamics model for the Sandveld system which captures land-use change, agricultural production, and groundwater abstraction and recharge. Using this model, we find little evidence that pressures on livelihoods result, either currently or in the immediate future, from ecological feedback effects. The model does indicate that the highest risks are associated with the financial viability of agriculture, in its present form, in the region. With lower margins, a drive towards economies of scale in agricultural production is more likely in the future. This process has had severe implications in some sectors already, with a 39% decrease in the number of potato producers in the Sandveld region between 2003 and 2009. These results highlight that an integrated approach to agricultural, economic and environmental management and planning is needed to capture the economic and ecological complexity and dynamics of the Sandveld system.

  16. Standardization of Social Credit System Initiated in China

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Introduction The current government advances that the order of market economy should be standardized and the social credit system of market economy in modern times should be established and completed. The social credit system should be formed on the basis of property right, supported by moral and high consciousness of social credit. Therefore, the basic framework and operation mechanism of the standards system for social credit will be established in 5 years in China in order to make standards play an important role in a regular market and the aspect of credit management, to improve administration's compliance with the regulation, and to facilitate the market economic order.

  17. Increase globe artichoke cropping sustainability using sub-surface drip-irrigation systems in a Mediterranean coastal area for reducing groundwater withdrawal

    Science.gov (United States)

    Mantino, Alberto; Marchina, Chiara; Bonari, Enrico; Fabbrizzi, Alessandro; Rossetto, Rudy

    2017-04-01

    During the last decades in coastal areas of the Mediterranean basin, human growth posed severe stresses on freshwater resources due to increasing demand by agricultural, industrial and civil activities, in particular on groundwater. This in turn led to worsening of water quality, loss/reduction of wetlands, up to soil salinization and abandonment of agricultural areas. Within the EU LIFE REWAT project a number of demonstration measures will take place in the lower Cornia valley (Livorno, Italy), both structural (pilot) and non-structural (education, dissemination and capacity building), aiming at achieving sustainable and participated water management. In particular, the five demonstration actions are related to: (1) set up of a managed aquifer recharge facility, (2) restoration of a Cornia river reach, (3) water saving in the civil water supply sector, (4) water saving in agriculture, (5) reuse of treated wastewater for irrigation purposes. Thus, the REWAT project general objective is to develop a new model of governance for sustainable development of the lower Cornia valley based on the water asset at its core. As per water use in agriculture, the lower Cornia valley is well known for the horticultural production. In this regard, globe artichoke (Cynara cardunculus L. var. scolymus L. (Fiori)) crops, a perennial cool-season vegetable, cover a surface of about 600 ha. In order to increase stability and productivity of the crop, about 2000 - 4000 m3 ha-1 yr-1 of irrigation water is required. Recent studies demonstrated that yield of different crops increases using Sub-surface Drip-Irrigation (SDI) system under high frequency irrigation management enhancing water use efficiency. In the SDI systems, the irrigation water is delivered to the plant root zone, below the soil surface by buried plastic tubes containing embedded emitters located at regular spacing. Within the LIFE REWAT, the specific objectives of the pilot on irrigation efficiency is to (i) demonstrate the

  18. [Continent colostomy and colon irrigation].

    Science.gov (United States)

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

    2000-01-01

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

  19. [Irrigants and intracanal medicaments in endodontics].

    Science.gov (United States)

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

    2003-01-01

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

  20. AGROCLIMATIC DETERMINANTS OF IRRIGATION NEEDS

    Directory of Open Access Journals (Sweden)

    Leszek Łabędzki

    2016-05-01

    Full Text Available The paper is a review of the so far used in Poland methods and criteria for assessing the needs of irrigation for planning purposes, the assessment because of the agroclimatic conditions and taking into account the soil water retention. Irrigation needs of the most are determined taking into account crop water deficits. This is the factor that is characterized by a shortage of precipitation in relation to the water requirements of crops. Some methods use only the meteorological parameters that determine the state of the atmosphere-soil-plant system, and some also take into account soil water retention and its availability for plants.

  1. Combining Multi-Agent Systems and Wireless Sensor Networks for Monitoring Crop Irrigation

    Directory of Open Access Journals (Sweden)

    Gabriel Villarrubia

    2017-08-01

    Full Text Available Monitoring mechanisms that ensure efficient crop growth are essential on many farms, especially in certain areas of the planet where water is scarce. Most farmers must assume the high cost of the required equipment in order to be able to streamline natural resources on their farms. Considering that many farmers cannot afford to install this equipment, it is necessary to look for more effective solutions that would be cheaper to implement. The objective of this study is to build virtual organizations of agents that can communicate between each other while monitoring crops. A low cost sensor architecture allows farmers to monitor and optimize the growth of their crops by streamlining the amount of resources the crops need at every moment. Since the hardware has limited processing and communication capabilities, our approach uses the PANGEA architecture to overcome this limitation. Specifically, we will design a system that is capable of collecting heterogeneous information from its environment, using sensors for temperature, solar radiation, humidity, pH, moisture and wind. A major outcome of our approach is that our solution is able to merge heterogeneous data from sensors and produce a response adapted to the context. In order to validate the proposed system, we present a case study in which farmers are provided with a tool that allows us to monitor the condition of crops on a TV screen using a low cost device.

  2. Irrigation in dose assessments models

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-05-01

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

  3. Irrigation in dose assessments models

    International Nuclear Information System (INIS)

    Bergstroem, Ulla; Barkefors, Catarina

    2004-05-01

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

  4. Effects of seven different irrigation techniques on debris and the ...

    African Journals Online (AJOL)

    Aim: Conventional manual irrigation with a syringe and needle remains widely accepted technique in the irrigation procedures. However, its flushing action has some limitations. Currently, several techniques and systems are available and reported to improve the i