WorldWideScience

Sample records for sun river irrigation

  1. Irrigation-based livelihood trends in river basins: theory and policy implications for irrigation development

    Science.gov (United States)

    Lankford, Bruce

    This paper examines irrigation development and policy in Tanzania utilising a livelihoods and river basin perspective. On the basis of observations, the author argues that river basins theoretically exhibit a sigmoid curve of irrigation development in three stages; proto-irrigation, irrigation-momentum and river basin management. This model arises from two governing factors. Firstly, irrigation is a complex livelihood activity that, although has benefits, also has costs, risks and alternatives that integrate across many systems; farmers implicitly understand this and enter into or keep out of irrigation accordingly. In the proto-irrigation stage, irrigators are less common, and irrigation is felt to be a relatively unattractive livelihood. In the irrigation-momentum stage, irrigators are drawn very much to irrigation in providing livelihood needs. Hence, given both of these circumstances, governments should be cautious about policies that call for the need to ‘provide irrigation’ (when farmers may not wish to irrigate) or to further increase it (when farmers already have the means and will to do so). Second, irrigation consumes water, generating externalities. Thus if irrigation momentum proceeds to the point when water consumption directly impacts on other sectors and livelihoods, (e.g. pastoralists, downstream irrigation, the environment) decision-makers should focus not necessarily on irrigation expansion, but on water management, allocation and conflict mediation. This three-stage theoretical model reminds us to take a balanced ‘livelihoods river-basin’ approach that addresses real problems in each given stage of river basin development and to develop policy accordingly. The paper contains a discussion on livelihood factors that affect entry into irrigation. It ends with a series of recommendations on policy; covering for example new large-scale systems; problems solving; and the use of an irrigation-river basin livelihoods approach. The recommendations

  2. The relationship between irrigation water demand and drought in the Yellow River basin

    Science.gov (United States)

    Wang, Yu; Wang, Weihao; Peng, Shaoming; Jiang, Guiqin; Wu, Jian

    2016-10-01

    In order to organize water for drought resistance reasonably, we need to study the relationship between irrigation water demand and meteorological drought in quantitative way. We chose five typical irrigation districts including the Qingtongxia irrigation district, Yellow River irrigation districts of Inner Mongolia in the upper reaches of the Yellow River, the Fen river irrigation district and the Wei river irrigation district in the middle reaches of the Yellow River and the irrigation districts in the lower reaches of the Yellow River as research area. Based on the hydrology, meteorology, groundwater and crop parameters materials from 1956 to 2010 in the Yellow River basin, we selected reconnaissance drought index (RDI) to analyze occurrence and evolution regularity of drought in the five typical irrigation districts, and calculated the corresponding irrigation water demand by using crop water balance equation. The relationship of drought and irrigation water demand in each typical irrigation district was studied by using grey correlation analysis and relevant analysis method, and the quantitative relationship between irrigation water demand and RDI was established in each typical irrigation district. The results showed that the RDI can be applied to evaluate the meteorological drought in the typical irrigation districts of the Yellow River basin. There is significant correlation between the irrigation water demand and RDI, and the grey correlation degree and correlation coefficient increased with increasing crops available effective rainfall. The irrigation water demand of irrigation districts in the upstream, middle and downstream of the Yellow River basin presented different response degrees to drought. The irrigation water demand increased 105 million m3 with the drought increasing one grade (RDI decreasing 0.5) in the Qingtongxia irrigation district and Yellow River irrigation districts of Inner Mongolia. The irrigation water demand increased 219 million m3

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-01-01

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

  4. 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.

  5. 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

  6. An assessment of global net irrigation water requirements from various water supply sources to sustain irrigation: rivers and reservoirs (1960–2000 and 2050

    Directory of Open Access Journals (Sweden)

    A. Khajuria

    2013-01-01

    Full Text Available Water supply sources for irrigation, such as rivers, reservoirs, and groundwater, are critically important for agricultural productivity. The current rapid increase in irrigation water use threatens sustainable food production. In this study, we estimated the time-varying dependency of the supply of irrigation water from rivers, large reservoirs with a greater than 1.0 km3 storage capacity, medium-size reservoirs with storage capacities ranging from 1.0 km3 to 3.0 Mm3, and non-local non-renewable blue water (NNBW, particularly taking into account variations in irrigation area during the period 1960–2000. We also estimated the future irrigation water requirements from water supply sources in addition to these four sources, using an irrigation area scenario. The net irrigation water requirements from various supply sources were assessed using the global H08 water resources model. The H08 model simulates water requirements on a daily basis at a resolution of 1.0° × 1.0°. We obtained net irrigation water from rivers and medium-size reservoirs, and determined that the NNBW increased continuously from 1960 to 1985, but the net irrigation water from large reservoirs increased only marginally. After 1985, the net irrigation water from rivers approached a critical limit with the continued expansion of the irrigation area. The irrigation water requirements from medium-size reservoirs and NNBW increased significantly following the expansion of the irrigation area and the increased storage capacity of medium-size reservoirs. Under the irrigation area scenario without climate change, global net irrigation water requirements from additional water supply sources will account for 26% of the total requirements in the year 2050. We found that expansion of irrigation areas due to population growth will generate an enormous demand for irrigation water from additional resources.

  7. An assessment of global net irrigation water requirements from various water supply sources to sustain irrigation: rivers and reservoirs (1960-2000 and 2050)

    Science.gov (United States)

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

    2013-01-01

    Water supply sources for irrigation, such as rivers, reservoirs, and groundwater, are critically important for agricultural productivity. The current rapid increase in irrigation water use threatens sustainable food production. In this study, we estimated the time-varying dependency of the supply of irrigation water from rivers, large reservoirs with a greater than 1.0 km3 storage capacity, medium-size reservoirs with storage capacities ranging from 1.0 km3 to 3.0 Mm3, and non-local non-renewable blue water (NNBW), particularly taking into account variations in irrigation area during the period 1960-2000. We also estimated the future irrigation water requirements from water supply sources in addition to these four sources, using an irrigation area scenario. The net irrigation water requirements from various supply sources were assessed using the global H08 water resources model. The H08 model simulates water requirements on a daily basis at a resolution of 1.0° × 1.0°. We obtained net irrigation water from rivers and medium-size reservoirs, and determined that the NNBW increased continuously from 1960 to 1985, but the net irrigation water from large reservoirs increased only marginally. After 1985, the net irrigation water from rivers approached a critical limit with the continued expansion of the irrigation area. The irrigation water requirements from medium-size reservoirs and NNBW increased significantly following the expansion of the irrigation area and the increased storage capacity of medium-size reservoirs. Under the irrigation area scenario without climate change, global net irrigation water requirements from additional water supply sources will account for 26% of the total requirements in the year 2050. We found that expansion of irrigation areas due to population growth will generate an enormous demand for irrigation water from additional resources.

  8. Long-term measurements of agronomic crop irrigation in the Mississippi Delta portion of the Lower Mississippi River Valley

    Science.gov (United States)

    With over 4 million ha irrigated cropland, the Lower Mississippi River Valley (LMRV) is a highly productive agricultural region where irrigation practices are similar and the Mississippi River Valley alluvial aquifer (MRVA) is a primary source of on-demand irrigation. Owing to agricultural exports, ...

  9. Impact of reservoirs on river discharge and irrigation water supply during the 20th century

    NARCIS (Netherlands)

    Biemans, H.; Haddeland, I.; Kabat, P.; Ludwig, F.; Hutjes, R.W.A.

    2011-01-01

    This paper presents a quantitative estimation of the impact of reservoirs on discharge and irrigation water supply during the 20th century at global, continental, and river basin scale. Compared to a natural situation the combined effect of reservoir operation and irrigation extractions decreased me

  10. Sun

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Sun Microsystems, Inc. is committed to open standards,a standardization system, and sharing within the information tech nology field, focusing not only on technical innovation, but also on new ideas, practices and future development.

  11. Removing sun glint from optical remote sensing images of shallow rivers

    Science.gov (United States)

    Overstreet, Brandon T.; Legleiter, Carl

    2017-01-01

    Sun glint is the specular reflection of light from the water surface, which often causes unusually bright pixel values that can dominate fluvial remote sensing imagery and obscure the water-leaving radiance signal of interest for mapping bathymetry, bottom type, or water column optical characteristics. Although sun glint is ubiquitous in fluvial remote sensing imagery, river-specific methods for removing sun glint are not yet available. We show that existing sun glint-removal methods developed for multispectral images of marine shallow water environments over-correct shallow portions of fluvial remote sensing imagery resulting in regions of unreliable data along channel margins. We build on existing marine glint-removal methods to develop a river-specific technique that removes sun glint from shallow areas of the channel without overcorrection by accounting for non-negligible water-leaving near-infrared radiance. This new sun glint-removal method can improve the accuracy of spectrally-based depth retrieval in cases where sun glint dominates the at-sensor radiance. For an example image of the gravel-bed Snake River, Wyoming, USA, observed-vs.-predicted R2 values for depth retrieval improved from 0.66 to 0.76 following sun glint removal. The methodology presented here is straightforward to implement and could be incorporated into image processing workflows for multispectral images that include a near-infrared band.

  12. Effect of irrigation management on soil salinization in Manas River Valley,Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The irrigated area of Manas River Valley in Northwest China is an example of the successful reclamation of massive land affected by shallow ground water levels and salinization.To determine the effect of irrigation management practices on soil salinization,soil profiles representing various soil types were sampled.The historical records on the characteristics of irrigation management practices,groundwater level and soil salts accumulation in this region at four key periods,namely:flood irrigation without drainage;flood irrigation with drainage but of low efficiency;irrigation in combination with lined irrigation canals and exploitation of groundwater;and irrigation with the application of water-saving irrigation techniques,were analyzed emphatically.In addition,the salinization status of cultivated land in 2010 and 2020 was also predicted by using analogism according to the relationship between soil salinization and irrigation practices.The results revealed that the application of the traditional irrigation methods,such as flood irrigation and ridge irrigation,resulted in a rapid rising of groundwater level and salts accumulation in soil surface layers.However,with the way of well irrigation and well drainage,the groundwater level and the desalinization in soil layers apparently lowered,leading to a substantial increase of crop yield.Currently,the application of drip irrigation under mulch decreased the salts concentration in soil layers and increased the crop yield.With the continuous application of drip irrigation,the average soil desalinization efficiency in soil layers may increase.It is predicted that the percentage of salinized land would be reduced to 35%-40% when irrigation water is utilized reasonably in 2010.With the high efficient utilization of irrigation water after 2020,the salinized land would remain below 30%.It is concluded that with the improvement of irrigation management,an obvious desalinization would appear in the soil surface layers and the

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

    Science.gov (United States)

    Etteieb, Selma; Cherif, Semia; Tarhouni, Jamila

    2017-03-01

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

  14. Herbicide and nutrient transport from an irrigation district into the South Saskatchewan River.

    Science.gov (United States)

    Cessna, A J; Elliott, J A; Tollefson, L; Nicholaichuk, W

    2001-01-01

    Pesticides and nutrients can be transported from treated agricultural land in irrigation runoff and thus can affect the quality of receiving waters. A 3-yr study was carried out to assess possible detrimental effects on the downstream water quality of the South Saskatchewan River due to herbicide and plant nutrient inputs via drainage water from an irrigation district. Automated water samplers and flow monitors were used to intensively sample the drainage water and to monitor daily flows in two major drainage ditches, which drained approximately 40% of the flood-irrigated land within the irrigation district. Over three years, there were no detectable inputs of ethalfluralin into the river and those of trifluralin were less than 0.002% of the amount applied to flood-irrigated fields. Inputs of MCPA, bromoxynil, dicamba and mecoprop were 0.06% or less of the amounts applied, whereas that for clopyralid was 0.31%. The relatively higher input (1.4%) of 2,4-D to the river was probably due its presence in the irrigation water. Corresponding inputs of P (as total P) and N (as nitrate plus ammonia) were 2.2 and 1.9% of applied fertilizer, respectively. Due to dilution of the drainage water in the river, maximum daily herbicide (with the exception of 2,4-D) and nutrient loadings to the river would not have resulted in significant concentration increases in the river water. There was no consistent remedial effect on herbicides entering the river due to passage of the drainage water through a natural wetland. In contrast, a considerable portion of the nutrients entering the river originated from the wetland.

  15. Supplemental irrigation potential and impact on downstream flow of Karkheh River basin in Iran

    Science.gov (United States)

    Hessari, Behzad; Bruggeman, Adriana; Akhoond-Ali, Ali Mohammad; Oweis, Theib; Abbasi, Fariborz

    2016-05-01

    Supplemental irrigation of rainfed winter crops improves and stabilises crop yield and water productivity. Although yield increases by supplemental irrigation are well established at the field level, its potential extent and impact on water resources at the basin level are less researched. This work presents a Geographic Information Systems (GIS)-based methodology for identifying areas that are potentially suitable for supplemental irrigation and a computer routine for allocating streamflow for supplemental irrigation in different sub-basins. A case study is presented for the 42 908 km2 upper Karkheh River basin (KRB) in Iran, which has 15 840 km2 of rainfed crop areas. Rainfed crop areas within 1 km from the streams, with slope classes 0-5, 0-8, 0-12, and 0-20 %, were assumed to be suitable for supplemental irrigation. Four streamflow conditions (normal, normal with environmental flow requirements, drought and drought with environmental flow) were considered for the allocation of water resources. Thirty-seven percent (5801 km2) of the rainfed croplands had slopes less than 5 %; 61 % (3559 km2) of this land was suitable for supplemental irrigation, but only 22 % (1278 km2) could be served with irrigation in both autumn (75 mm) and spring (100 mm), under normal flow conditions. If irrigation would be allocated to all suitable land with slopes up to 20 %, 2057 km2 could be irrigated. This would reduce the average annual outflow of the upper KRB by 9 %. If environmental flow requirements are considered, a maximum (0-20 % slopes) of 1444 km2 could receive supplemental irrigation. Under drought conditions a maximum of 1013 km2 could be irrigated, while the outflow would again be reduced by 9 %. Thus, the withdrawal of streamflow for supplemental irrigation has relatively little effect on the outflow of the upper KRB. However, if the main policy goal would be to improve rainfed areas throughout the upper KRB, options for storing surface water need to be developed.

  16. 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

  17. Closing the irrigation deficit in Cambodia: Implications for transboundary impacts on groundwater and Mekong River flow

    Science.gov (United States)

    Erban, Laura E.; Gorelick, Steven M.

    2016-04-01

    Rice production in Cambodia, essential to food security and exports, is largely limited to the wet season. The vast majority (96%) of land planted with rice during the wet season remains fallow during the dry season. This is in large part due to lack of irrigation capacity, increases in which would entail significant consequences for Cambodia and Vietnam, located downstream on the Mekong River. Here we quantify the extent of the dry season "deficit" area in the Cambodian Mekong River catchment, using a recent agricultural survey and our analysis of MODIS satellite data. Irrigation of this land for rice production would require a volume of water up to 31% of dry season Mekong River flow to Vietnam. However, the two countries share an aquifer system in the Mekong Delta, where irrigation demand is increasingly met by groundwater. We estimate expansion rates of groundwater-irrigated land to be >10% per year in the Cambodian Delta using LANDSAT satellite data and simulate the effects of future expansion on groundwater levels over a 25-year period. If groundwater irrigation continues to expand at current rates, the water table will drop below the lift limit of suction pump wells, used for domestic supply by >1.5 million people, throughout much of the area within 15 years. Extensive groundwater irrigation jeopardizes access for shallow domestic water supply wells, raises the costs of pumping for all groundwater users, and may exacerbate arsenic contamination and land subsidence that are already widespread hazards in the region.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-11-01

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

  19. Impact of irrigation based sugarcane cultivation on the Chiredzi and Runde Rivers quality, Zimbabwe.

    Science.gov (United States)

    Nhiwatiwa, Tamuka; Dalu, Tatenda; Brendonck, Luc

    2017-06-01

    Agriculture is vital in sustaining human livelihoods. However, agriculture as it is currently practiced, is contributing to the degradation of freshwater ecosystems globally. We investigated impacts of irrigation return flows from sugarcane farming on water quality and health status of the Chiredzi and Runde Rivers, a biodiversity hotspot region in south-eastern Lowveld of Zimbabwe. The water quality at inlets from the crop field into the wetland system; wetland outlets into the river systems; and river sites upstream and downstream of wetland outlets were monitored during the dry and wet seasons. The wetland system formed naturally from excessive drainage from the cane fields but its purifying capacity was unknown to date. An assessment of the water physical-chemical variables (at all sites) and macroinvertebrate communities (at river sites only) was carried out. Results showed that the wetland was deficient in its purifying capacity as it was already saturated by salts and nutrients from high irrigation return flow loads. A significant seasonal variation was observed for conductivity, reactive phosphorus (RP), pH and total phosphorus (TP) concentrations among the inlets to the wetland whereas among the river sites significant seasonal differences were observed for ammonium, dissolved oxygen, nitrate, RP, pH, TP and turbidity concentrations during the dry season. From the macroinvertebrate community data the impact of the irrigation return flows on the river system was apparent, as the good water quality sites were characterised by a high diversity of pollution sensitive macroinvertebrate taxa, while the irrigation impacted sites were characterised and dominated by pollution tolerant taxa. High ion concentration (conductivity and salinity) and pH were found to be important in structuring macroinvertebrate communities as determined using multivariate analysis in the river system. In conclusion, the river water quality was significantly impacted by irrigation return

  20. Feasibility of Natore Rubber Dam on Mahanonda River in Bangladesh and its Performance on Irrigation

    Directory of Open Access Journals (Sweden)

    Md. Sazadul Hasan

    2016-07-01

    Full Text Available Low rainfall in winter causes a great problem on irrigation. Bangladesh Agricultural Research Council (BARC started research on this problem from 1974. In 1994-95, Rubber Dam projects have been taken by BIC (Beijing IWHR Corporation in Bangladesh as it is very convenience and effective in both irrigation and cultivation of crops in winter. After installing, it is very important and challenging task to study the suitability and effect of Rubber Dam on agriculture. In this research work, the analysis of Rubber Dam in Natore, Bangladesh and its suitability on Mahanonda River has been analyzed and also studied its performance on irrigation. Also Bakkhali and Idgaon Rubber Dam were analyzed for the performance evaluation of Rubber Dam projects in Bangladesh for irrigation development. Then, feasibility of Natore Rubber Dam was studied and briefly discussed about its probable effect and benefit on agriculture. Reservoir capacity was also determined on the basis of a theoretical concept known as flow mass curve. Results of performance evaluation in irrigation were expressed in three groups: hydraulic, agricultural and socio-economic. Results of the analyses of hydraulic indicators showed that water supply is available. Agricultural performance, evaluated in terms of irrigated area was satisfactory. Analyses of socio-economic indicators showed that the Rubber Dam projects were financially viable in terms of profitability of farmers. Finally results were found that, it has a great probable effect on national economic and thus an alteration method of irrigation instead of uses of ground water. Thus, a comparative capital and operation and management cost analyses of different irrigation technologies has been carried out to ascertain the viability of Rubber Dam technology in irrigation development.

  1. 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).

  2. Nitrogen and salt loads in the irrigation return flows of the Ebro River Basin (Spain)

    Science.gov (United States)

    Isidoro, Daniel; Balcells, Maria; Clavería, Ignacio; Dechmi, Farida; Quílez, Dolores; Aragüés, Ramón

    2013-04-01

    The conservation of the quality of surface waters demanded by the European Water Framework Directive requires, among others, an assessment of the irrigation-induced pollution. The contribution of the irrigation return flows (IRF) to the pollution of the receiving water bodies is given by its pollutant load, since this load determines the quality status or pollutant concentration in these water bodies. The aim of this work was to quantify the annual nitrogen and salt loads in the IRF of four irrigated catchments within the Ebro River Basin: Violada (2006-10), Alcanadre (2008-10), Valcuerna (2010), and Clamor Amarga (2010). The daily flow (Q), salt (EC) and nitrate concentration (NO3) were measured in the drainage outlets of each basin. The net irrigation-induced salt and nitrogen loads were obtained from these measurements after discounting the salt and nitrogen inputs from outside the catchments and the non-irrigated areas. The N-fertilizer applications were obtained from farmer surveys and animal farming statistical sources. Irrigation water salinity was very low in all catchments (EC corn-dominated Valcuerna in 2010 to 63 kg/ha in 2008 in Violada, when farmers barely applied fertilizers due to the irrigation modernization works in progress that year. The highest N applications derived from pig slurry applications by farmers that used their lands as disposal sites for their farm residues. The highest NO3 concentrations (mean of 113 mg/L) and annual N loads (mean of 38 kg/ha) were found in Valcuerna, the most intense corn sprinkler-irrigated catchment. The lowest NO3 concentrations (21 mg/L; 5 times lower than Valcuerna) were measured in the Alcanadre flood-irrigated catchment. In contrast, Alcanadre N loads (21 kg/ha) were only about two times lower than in Valcuerna, due to the higher IRF volumes in Alcanadre (353 mm versus 132 mm in Valcuerna). Irrigation modernization in Violada decreased N loads from 20 to 5 kg N/ha (four times lower) due to the sharp

  3. Does the Limpopo River Basin have sufficient water for massive irrigation development in the plains of Mozambique?

    NARCIS (Netherlands)

    Zaag, van der P.; Juizo, D.; Vilanculos, A.; Bolding, J.A.; Post Uiterweer, N.C.

    2010-01-01

    This paper verifies whether the water resources of the transboundary Limpopo River Basin are sufficient for the planned massive irrigation developments in the Mozambique part of this basin, namely 73,000 ha, in addition to existing irrigation (estimated at 9400 ha), and natural growth of common use

  4. Agricultural irrigated land-use inventory for the counties in the Suwannee River Water Management District in Florida, 2015

    Science.gov (United States)

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

    2016-07-28

    A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to accurately estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage during the 2015 growing season was developed for 13 of the 15 counties that compose the Suwannee River Water Management District. The irrigated areas were delineated using land-use data, orthoimagery, and information obtained from the water management district consumptive water-use permits that were then field verified between May and November of 2015. Selected attribute data were collected for the irrigated areas, including crop type, primary water source, and type of irrigation system. Results indicate that an estimated 113,134 acres were either irrigated or had potential for irrigation in all or part of the 13 counties within the Suwannee River Water Management District during 2015. This estimate includes 108,870 acres of field-verified, irrigated crops and 4,264 acres of irrigated land observed as (1) idle (with an irrigation system visible but no crop present at the time of the field-verification visit), (2) acres that could not be verified during field visits, or (3) acres that were located on publicly owned research lands.

  5. Impact of Potentially Contaminated River Water on Agricultural Irrigated Soils in an Equatorial Climate

    Directory of Open Access Journals (Sweden)

    Juan M. Trujillo-González

    2017-06-01

    Full Text Available Globally, it is estimated that 20 million hectares of arable land are irrigated with water that contains residual contributions from domestic liquids. This potentially poses risks to public health and ecosystems, especially due to heavy metals, which are considered dangerous because of their potential toxicity and persistence in the environment. The Villavicencio region (Colombia is an equatorial area where rainfall (near 3000 mm/year and temperature (average 25.6 °C are high. Soil processes in tropical conditions are fast and react quickly to changing conditions. Soil properties from agricultural fields irrigated with river water polluted by a variety of sources were analysed and compared to non-irrigated control soils. In this study, no physico-chemical alterations were found that gave evidence of a change due to the constant use of river water that contained wastes. This fact may be associated with the climatic factors (temperature and precipitation, which contribute to fast degradation of organic matter and nutrient and contaminants (such as heavy metals leaching, or to dilution of wastes by the river.

  6. The traditional symbolism of the Sun Dance Lodge among the Wind River Shoshoni

    Directory of Open Access Journals (Sweden)

    Åke Hultkrantz

    1979-01-01

    Full Text Available Of all the North American Indian religious ceremonies no one is as spectacular and as well-known as the Sun Dance of the Plains Indians. The information collected on the subject since the turn of the century is quite extensive. However, while there is a mass of materials on the outer features of the Dance, on behavioural and ritual aspects, there is very little information on its religious aspects, in particular the meaning of the ritual.The following account is an attempt to view the religious symbolism of the Wind River Shoshoni Sun Dance lodge in a "meaningful" perspective. Attention is paid not only to the ideology of the Dance as such but also and foremost to the concrete elements of the Sun Dance structure which together throw further light on this ideology. A particular place in the analysis will be devoted to a new scholarly interpretation according to which the Shoshoni Sun Dance serves as a revitalization cult.

  7. Secondary salinization and evapotranspiration under mulched drip irrigation condition in Tarim River basin of northwestern China

    Science.gov (United States)

    Tian, Fuqiang; Hu, Hongchang; Zhang, Zhi; Hu, Heping

    2013-04-01

    The secondary salinization induced by irrigation has been presented as a crucial threat to agriculture all over the world, especially in semi-arid and arid regions. Mulched drip irrigation (MDI), as a new micro-irrigation approach incorporating surface drip irrigation method and film mulching technique, has been widely applied in water scarce regions including Tarim River basin of northwestern China. However, salts are likely to build up in the surface soil due to the deficient leaching water in such an irrigation condition. To explore this new kind of secondary salinization issue, the oasis eco-hydrology experimental research station were established in 2008 in a cotton field of Xinjiang, northwestern China. More than 40,000 soil samples were collected to monitor soil moisture and salinity condition within the 1.5 meter depth. The patterns of soil salinity distribution under MDI along the horizontal direction as well as vertical direction have been explored. The results did show that secondary salinization tends to occur in the experimental field under mulched drip irrigation, and winter flush could leach most soil salt in the root zone into groundwater and keep salt balance to mitigate the soil salinization. Meanwhile, soil salt always migrates with the soil water flux such as irrigation and groundwater recharge. Therefore the understanding of water balance is of great importance for estimating soil salinity accumulation, of which evapotranspiration (ET) is the key process, especially in the semi-arid and arid area. In our study, in order to quantify the relation between salinity balance and water balance, ET were derived from a range of measurement systems including eddy covariance, soil water budget (gravimetric methods, Hydra probe, TDT probe and groundwater table sensor, et al.), sap flow and portable photosynthetic system during cotton growing period. Our study is unique in its focus on ET scale issue ranging from leaf and plant scale to field. The up

  8. Risk Assessment of Regional Irrigation Water Demand and Supply in an Arid Inland River Basin of Northwestern China

    Directory of Open Access Journals (Sweden)

    Bin Guo

    2015-09-01

    Full Text Available Irrigation water demand accounts for more than 95% of the total water use in the Kaidu-kongqi River Basin. Determination of the spatial and temporal trends in irrigation water demand is important for making sustainable and wise water management strategies in this highly water deficit region. In this study, the spatial and temporal trends in irrigation water demand as well as net crop irrigation water requirements for nine major crops during 1985–2009 were analyzed by combining the Penman-Monteith equation recommended by Food and Agriculture Organization (FAO and GIS technology. The regional water stress was also evaluated based on the total irrigation water demand and river discharge at the annual and monthly scales. The results indicated that the annual irrigation water demand in this arid region showed a significant increasing trend during the past 25 years. Total irrigation water demand increased from 14.68 × 108 m3 in 1985 to 34.15 × 108 m3 in 2009. The spatial pattern of total irrigation water demand was significantly affected by the changes in cotton growing area. Due to differences in crop planting structure, the monthly average irrigation water demands in Korla City and Yuli County amounted to the peak in July, while those in other regions reached the maximum in June. Although the annual river runoff was much larger than the irrigation water demand, there was serious water deficit during the critical water use period in May and June in some dry years. The presented study provides important information for managers and planners on sustainable use of water resources in this arid region.

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

    Science.gov (United States)

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

    2014-10-01

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

  10. Optimal dynamic water allocation: Irrigation extractions and environmental tradeoffs in the Murray River, Australia

    Science.gov (United States)

    Grafton, R. Quentin; Chu, Hoang Long; Stewardson, Michael; Kompas, Tom

    2011-12-01

    A key challenge in managing semiarid basins, such as in the Murray-Darling in Australia, is to balance the trade-offs between the net benefits of allocating water for irrigated agriculture, and other uses, versus the costs of reduced surface flows for the environment. Typically, water planners do not have the tools to optimally and dynamically allocate water among competing uses. We address this problem by developing a general stochastic, dynamic programming model with four state variables (the drought status, the current weather, weather correlation, and current storage) and two controls (environmental release and irrigation allocation) to optimally allocate water between extractions and in situ uses. The model is calibrated to Australia's Murray River that generates: (1) a robust qualitative result that "pulse" or artificial flood events are an optimal way to deliver environmental flows over and above conveyance of base flows; (2) from 2001 to 2009 a water reallocation that would have given less to irrigated agriculture and more to environmental flows would have generated between half a billion and over 3 billion U.S. dollars in overall economic benefits; and (3) water markets increase optimal environmental releases by reducing the losses associated with reduced water diversions.

  11. Biophysical indicators based on satellite images in an irrigated area at the São Francisco River Basin, Brazil

    Science.gov (United States)

    Leivas, Janice F.; Teixeira, Antônio Heriberto C.; Bayma-Silva, Gustavo; Ronquim, Carlos Cesar; Ribeiro da Silva Reis, João. Batista

    2016-10-01

    The Jaíba Irrigated Perimeter is a large irrigated agriculture area, located in the region Forest Jaíba between the São Francisco and Verde Grande rivers, in the Brazilian semi-arid region. In 2014, irrigators this the region face losses in the interruption of new plantings in irrigated areas due to water scarcity. The objective of this study is combine the model to estimate the Monteith BIO with the SAFER algorithm in the case of obtaining ET, to analyze the dynamics of natural vegetation and irrigated crops in water scarcity period. For application of the model are necessary data from meteorological stations and satellite images. Were used 23 satellite images of MODIS with spatial resolution of 250m and temporal 16 days, of 2014 year. For analyze the results, we used central pivots irrigation mask of Minas Gerais state, Brazil. In areas with irrigated agriculture with central pivot, the mean values of BIO over the year 2014 were 88.96 kg.ha-1.d-1. The highest values occurred between April 23 and May 8, with BIO 139 kg.ha-1.d-1. For areas with natural vegetation, the average BIO was 88.34 kg.ha-1.d-1 with lower values in September. Estimates of ET varied with the lowest values of ET observed in natural vegetation 1.91+/-1.22 mm.d-1 and the highest values in irrigated area is observed 3.51+/-0.97 mm.d-1. Results of this study can assist in monitoring of river basins, contributing to the management irrigated agriculture, with the trend of scarcity of water resources and increasing conflicts for the water use.

  12. A metagenomic assessment of viral contamination on fresh parsley plants irrigated with fecally tainted river water.

    Science.gov (United States)

    Fernandez-Cassi, X; Timoneda, N; Gonzales-Gustavson, E; Abril, J F; Bofill-Mas, S; Girones, R

    2017-09-18

    Microbial food-borne diseases are still frequently reported despite the implementation of microbial quality legislation to improve food safety. Among all the microbial agents, viruses are the most important causative agents of food-borne outbreaks. The development and application of a new generation of sequencing techniques to test for viral contaminants in fresh produce is an unexplored field that allows for the study of the viral populations that might be transmitted by the fecal-oral route through the consumption of contaminated food. To advance this promising field, parsley was planted and grown under controlled conditions and irrigated using contaminated river water. Viruses polluting the irrigation water and the parsley leaves were studied by using metagenomics. To address possible contamination due to sample manipulation, library preparation, and other sources, parsley plants irrigated with nutritive solution were used as a negative control. In parallel, viruses present in the river water used for plant irrigation were analyzed using the same methodology. It was possible to assign viral taxons from 2.4 to 74.88% of the total reads sequenced depending on the sample. Most of the viral reads detected in the river water were related to the plant viral families Tymoviridae (66.13%) and Virgaviridae (14.45%) and the phage viral families Myoviridae (5.70%), Siphoviridae (5.06%), and Microviridae (2.89%). Less than 1% of the viral reads were related to viral families that infect humans, including members of the Adenoviridae, Reoviridae, Picornaviridae and Astroviridae families. On the surface of the parsley plants, most of the viral reads that were detected were assigned to the Dicistroviridae family (41.52%). Sequences related to important viral pathogens, such as the hepatitis E virus, several picornaviruses from species A and B as well as human sapoviruses and GIV noroviruses were detected. The high diversity of viral sequences found in the parsley plants

  13. Karez (qanat) irrigation in the Helmand River Basin, Afghanistan: a vanishing indigenous legacy

    Science.gov (United States)

    Goes, B. J. M.; Parajuli, U. N.; Haq, Mohammad; Wardlaw, R. B.

    2017-03-01

    A karez is a gently sloping tunnel into a hillside with a series of vertical shafts. At the upstream end, the karez depresses the water table such that groundwater enters the tunnel. Farmers all over Afghanistan have built and managed karezes for centuries using indigenous knowledge. This report focuses on karezes in the Helmand River Basin in southern Afghanistan, and describes the location of karezes in relation to geology, technological and managerial aspects of karez irrigation, and their current status. Karez irrigation has declined in recent decades due to the following: a prolonged reduction in precipitation, increase in number of boreholes that lower the water table below the karez tunnel, breakdown in community-based management, and reduced maintenance. Systematic field measurements are a challenge in the Helmand Basin due to security constraints. The current condition and management of the karezes have been assessed through short field visits and structured focus-group discussions with karez farmers and staff from provincial departments. The surveys indicate that over half of the karezes in the Helmand Basin have gone dry. Furthermore, the flow in karezes that are still operational has also declined significantly. The report demonstrates the value of using data from the US National Centres for Environmental Prediction (NCEP) Reanalysis 1 project, to estimate historic precipitation for various karez zones in this data-poor basin. Strategies for rehabilitating karezes are discussed. Rehabilitation is financially expensive in comparison to drilling new boreholes, but karezes are part of the national heritage of Afghanistan and can facilitate social cohesion.

  14. Karez (qanat) irrigation in the Helmand River Basin, Afghanistan: a vanishing indigenous legacy

    Science.gov (United States)

    Goes, B. J. M.; Parajuli, U. N.; Haq, Mohammad; Wardlaw, R. B.

    2016-12-01

    A karez is a gently sloping tunnel into a hillside with a series of vertical shafts. At the upstream end, the karez depresses the water table such that groundwater enters the tunnel. Farmers all over Afghanistan have built and managed karezes for centuries using indigenous knowledge. This report focuses on karezes in the Helmand River Basin in southern Afghanistan, and describes the location of karezes in relation to geology, technological and managerial aspects of karez irrigation, and their current status. Karez irrigation has declined in recent decades due to the following: a prolonged reduction in precipitation, increase in number of boreholes that lower the water table below the karez tunnel, breakdown in community-based management, and reduced maintenance. Systematic field measurements are a challenge in the Helmand Basin due to security constraints. The current condition and management of the karezes have been assessed through short field visits and structured focus-group discussions with karez farmers and staff from provincial departments. The surveys indicate that over half of the karezes in the Helmand Basin have gone dry. Furthermore, the flow in karezes that are still operational has also declined significantly. The report demonstrates the value of using data from the US National Centres for Environmental Prediction (NCEP) Reanalysis 1 project, to estimate historic precipitation for various karez zones in this data-poor basin. Strategies for rehabilitating karezes are discussed. Rehabilitation is financially expensive in comparison to drilling new boreholes, but karezes are part of the national heritage of Afghanistan and can facilitate social cohesion.

  15. Effect of irrigation pumpage during drought on karst aquifer systems in highly agricultural watersheds: example of the Apalachicola-Chattahoochee-Flint river basin, southeastern USA

    Science.gov (United States)

    Mitra, Subhasis; Srivastava, Puneet; Singh, Sarmistha

    2016-09-01

    In the Apalachicola-Chattahoochee-Flint (ACF) river basin in Alabama, Georgia, and Florida (USA), population growth in the city of Atlanta and increased groundwater withdrawal for irrigation in southwest Georgia are greatly affecting the supply of freshwater to downstream regions. This study was conducted to understand and quantify the effect of irrigation pumpage on the karst Upper Floridan Aquifer and river-aquifer interactions in the lower ACF river basin in southwest Georgia. The groundwater MODular Finite-Element model (MODFE) was used for this study. The effect of two drought years, a moderate and a severe drought year, were simulated. Comparison of the results of the irrigated and non-irrigated scenarios showed that groundwater discharge to streams is a major outflow from the aquifer, and irrigation can cause as much as 10 % change in river-aquifer flux. The results also show that during months with high irrigation (e.g., June 2011), storage loss (34 %), the recharge and discharge from the upper semi-confining unit (30 %), and the river-aquifer flux (31 %) are the major water components contributing towards the impact of irrigation pumpage in the study area. A similar scenario plays out in many river basins throughout the world, especially in basins in which underlying karst aquifers are directly connected to a nearby stream. The study suggests that improved groundwater withdrawal strategies using climate forecasts needs to be developed in such a way that excessive withdrawals during droughts can be reduced to protect streams and river flows.

  16. Estimates of deep percolation beneath native vegetation, irrigated fields, and the Amargosa-River Channel, Amargosa Desert, Nye County, Nevada

    Science.gov (United States)

    Stonestrom, David A.; Prudic, David E.; Laczniak, Randell J.; Akstin, Katherine C.; Boyd, Robert A.; Henkelman, Katherine K.

    2003-01-01

    The presence and approximate rates of deep percolation beneath areas of native vegetation, irrigated fields, and the Amargosa-River channel in the Amargosa Desert of southern Nevada were evaluated using the chloride mass-balance method and inferred downward velocities of chloride and nitrate peaks. Estimates of deep-percolation rates in the Amargosa Desert are needed for the analysis of regional ground-water flow and transport. An understanding of regional flow patterns is important because ground water originating on the Nevada Test Site may pass through the area before discharging from springs at lower elevations in the Amargosa Desert and in Death Valley. Nine boreholes 10 to 16 meters deep were cored nearly continuously using a hollow-stem auger designed for gravelly sediments. Two boreholes were drilled in each of three irrigated fields in the Amargosa-Farms area, two in the Amargosa-River channel, and one in an undisturbed area of native vegetation. Data from previously cored boreholes beneath undisturbed, native vegetation were compared with the new data to further assess deep percolation under current climatic conditions and provide information on spatial variability. The profiles beneath native vegetation were characterized by large amounts of accumulated chloride just below the root zone with almost no further accumulation at greater depths. This pattern is typical of profiles beneath interfluvial areas in arid alluvial basins of the southwestern United States, where salts have been accumulating since the end of the Pleistocene. The profiles beneath irrigated fields and the Amargosa-River channel contained more than twice the volume of water compared to profiles beneath native vegetation, consistent with active deep percolation beneath these sites. Chloride profiles beneath two older fields (cultivated since the 1960?s) as well as the upstream Amargosa-River site were indicative of long-term, quasi-steady deep percolation. Chloride profiles beneath the

  17. Monitoring and assessment of treated river, rain, gully pot and grey waters for irrigation of Capsicum annuum.

    Science.gov (United States)

    Al-Isawi, Rawaa H K; Almuktar, Suhad A A A N; Scholz, Miklas

    2016-05-01

    This study examines the benefits and risks associated with various types of wastewater recycled for vegetable garden irrigation and proposes the best water source in terms of its water quality impact on crop yields. The aim was to evaluate the usability of river, rain, gully pot, real grey and artificial grey waters to water crops. The objectives were to evaluate variables and boundary conditions influencing the growth of chillies (De Cayenne; Capsicum annuum (Linnaeus) Longum Group 'De Cayenne') both in the laboratory and in the greenhouse. A few irrigated chilli plants suffered from excess of some nutrients, which led to a relatively poor harvest. High levels of trace minerals and heavy metals were detected in river water, gully pot effluent and greywater. However, no significant differences in plant yields were observed, if compared with standards and other yields worldwide. The highest yields were associated with river water both in the laboratory and in the greenhouse. Plant productivity was unaffected by water quality due to the high manganese, potassium, cadmium and copper levels of the greywater. These results indicate the potential of river water and gully pot effluent as viable alternatives to potable water for irrigation in agriculture.

  18. Areas permitted for irrigation, storage, evaporation, and disposal of treated sewage effluent in the upper Carson River Basin, Nevada and California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of areas permitted for irrigation, storage, evaporation, and disposal of treated sewage effluent in the Upper Carson River Basin, California...

  19. Hydrologic Simulation of a Winter Wheat–Summer Maize Cropping System in an Irrigation District of the Lower Yellow River Basin, China

    Directory of Open Access Journals (Sweden)

    Lei Liu

    2017-01-01

    Full Text Available Conflicts between water supply and water demand are intensifying in irrigation districts along the Lower Yellow River due to climate change and human activities. To ensure both adequate food supply and water resource sustainability in China, the Soil and Water Assessment Tool (SWAT model was used to simulate the water balance and water use of agro-ecosystems in an irrigation district of the lower Yellow River Basin, China. Simulated average annual irrigation requirements decreased from 1969 to 2010. Irrigation requirements during the winter wheat season decreased owing to reduced reference evapotranspiration and increased precipitation. Annual evapotranspiration (ET increased with increasing irrigation volume, and differences among irrigation scenarios were mainly due to ET of winter wheat. Water deficit typically occurred during winter wheat seasons with less precipitation. Field seepage and surface runoff tended to occur in years with high precipitation, particularly during the summer maize season under full irrigation and scheduled irrigation scenarios. Frequent and heavy irrigation did not always lead to high water use efficiency. To cope with limited water resources in this region, it is necessary to properly irrigate crops based on soil water content and take full advantage of precipitation and surface runoff during the summer maize season.

  20. An agricultural drought index to incorporate the irrigation process and reservoir operations: A case study in the Tarim River Basin

    Science.gov (United States)

    Li, Zehua; Hao, Zhenchun; Shi, Xiaogang; Déry, Stephen J.; Li, Jieyou; Chen, Sichun; Li, Yongkun

    2016-08-01

    To help the decision making process and reduce climate change impacts, hydrologically-based drought indices have been used to determine drought severity in the Tarim River Basin (TRB) over the past decades. As the major components of the surface water balance, however, the irrigation process and reservoir operations have not been incorporated into drought indices in previous studies. Therefore, efforts are needed to develop a new agricultural drought index, which is based on the Variable Infiltration Capacity (VIC) model coupled with an irrigation scheme and a reservoir module. The new drought index was derived from the simulated soil moisture data from a retrospective VIC simulation from 1961 to 2007 over the irrigated area in the TRB. The physical processes in the coupled VIC model allow the new agricultural drought index to take into account a wide range of hydrologic processes including the irrigation process and reservoir operations. Notably, the irrigation process was found to dominate the surface water balance and drought evolution in the TRB. Furthermore, the drought conditions identified by the new agricultural drought index presented a good agreement with the historical drought events that occurred in 1993-94, 2004, and 2006-07, respectively. Moreover, the spatial distribution of coupled VIC model outputs using the new drought index provided detailed information about where and to what extent droughts occurred.

  1. Irrigation system and land use effect on surface water quality in river, at lake Dianchi, Yunnan, China

    Institute of Scientific and Technical Information of China (English)

    Takashi Tanaka; Takahiro Sato; Kazuo Watanabe; Ying Wang; Dan Yang; Hiromo Inoue; Kunzhi Li

    2013-01-01

    The surface water samples were collected in river Dahe and its tributaries,which flow into severely eutrophic lake Dianchi,Yunnan Province,China,in order to elucidate factors controlling water quality fluctuations.The temporal and spatial distribution of water quality tendency was observed.The water quality of each river is dependent on the hydrology effect such water gate and circulating irrigation system.We must consider the hydrology effect to accurately understand water quality variations of river in this study field.In river without highly circulating irrigation system or water gate effect,the downstream nitrate nitrogen (NO3-N) concentration increase occurred in area dominated by open field cultivation,whereas the NO3-N concentration was constant or decreased in area dominated by greenhouse land use.This result suggests that greenhouse covers the soil from precipitation,and nitrate load of greenhouse could be less than that of open field cultivation while the rainfall event.In the upper reaches of river,where is dominated by open field cultivation,there were no sharp increase dissolved molybdate reactive phosphorus and total phosphorus concentration,but P load was accumulated in the lower reaches of river,whose predominant land use is greenhouse.Although the P sources is unclear in this study,greenhouse area may have potential of P loads due to its high P content in greenhouse soil.Considering hydrology effect is necessary to determine what the major factor is influencing the water quality variation,especially in area with highly complicated irrigation system in this studying site.

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

    Science.gov (United States)

    Senzanje, A.; van der Zaag, P.

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

  3. Physical, chemical, and biological data for detailed study of irrigation drainage in the San Juan River area, New Mexico, 1993-94, with supplemental data, 1991-95

    Science.gov (United States)

    Thomas, C.L.; Lusk, J.D.; Bristol, R.S.; Wilson, R.M.; Shineman, A.R.

    1997-01-01

    In response to increasing concern about the quality of irrigation drainage and its potential effects on fish, wildlife, and human health, the U.S. Department of the Interior formed an interbureau task group to prepare a plan for investigating water- quality problems on irrigation projects sponsored by the Department of the Interior. The San Juan River area in northwestern New Mexico was one of the areas designated for study. Investigators collected water, bottom-sediment, soil, and biological samples at more than 50 sites in the San Juan River area during 1993-94. Sample sites included (1) sites located within Department of the Interior irrigation project service areas, or areas that receive drainage from irrigation projects; (2) reference sites for comparison with irrigation project sites; and (3) sites located within the reach of the San Juan River from Navajo Dam to 10 miles downstream from the dam. The types of habitat sampled included the main stem of the San Juan River, backwater areas adjacent to the San Juan River, tributaries to the San Juan River, ponds, seeps, irrigation-delivery canals, irrigation-drainage canals, a stock tank, and shallow ground water. The types of media sampled included water, bottom sediment, soil, aquatic plants, aquatic invertebrates, amphibians, and fish. Semipermeable-membrane devices were used as a surrogate medium to sample both air and water in some instances. Sample measurements included concentrations of major ions, trace elements, organochlorine pesticides, polychlorinated biphenyls, polycyclic-aromatic-hydrocarbon compounds, and stable isotopes of hydrogen and oxygen. This report presents tables of physical, chemical, and biological data collected for the U.S. Department of the Interior National Irrigation Water-Quality Program. Additionally, supplemental physical, chemical, and biological data collected in association with the Navajo Indian Irrigation Project are presented.

  4. Sustainability Assessment of Large Irrigation Dams in Senegal: A Cost-Benefit Analysis for the Senegal River Valley

    Directory of Open Access Journals (Sweden)

    Stanislaw eManikowski

    2016-03-01

    Full Text Available Starting in the 1970s, the Senegalese Government invested in the development of irrigated schemes in the Senegalese part of the Senegal River Valley (S-SRV. From that time to 2012, the irrigated schemes increased from 10,000 ha to more than 110,000 ha. In the meantime, the economic viability of these schemes started to be questioned. It also appeared that the environmental health and social costs might outweigh the benefits of irrigation. Using a life cycle assessment approach and project cost-benefits modelling, this study (i quantified the costs and benefits of the S-SRV irrigated rice production, (ii evaluated the costs and benefits of its externalities and (iii discussed the irrigated rice support policy. The net financial revenues from the irrigated schemes were positive, but their economic equivalences. The economic return rate (EER was below the expected 12% and the net present value (NPV over 20 years of the project represented a loss of about US$-19.6 million. However, if we also include the project’s negative externalities, such as the reduced productivity of the valley ecosystems, protection cost of human health, environmental degradation and social impacts, then the NPV would be much worse, approximately US$-572.1 million. Therefore, the results show that to stop the economic loss and alleviate the human suffering, the S-SRV development policy should be revised using an integrated approach and the exploitation technology should aim at environmental sustainability. This paper may offer useful insights for reviewing the current Senegalese policies for the valley, as well as for assessing other similar cases or future projects worldwide, particularly in critical zones of developing countries.

  5. Climate change impacts on irrigated rice and wheat production in Gomti River basin of India: a case study.

    Science.gov (United States)

    Abeysingha, N S; Singh, Man; Islam, Adlul; Sehgal, V K

    2016-01-01

    Potential future impacts of climate change on irrigated rice and wheat production and their evapotranspiration and irrigation requirements in the Gomti River basin were assessed by integrating a widely used hydrological model "Soil and Water Assessment Tool (SWAT)" and climate change scenario generated from MIROC (HiRes) global climate model. SWAT model was calibrated and validated using monthly streamflow data of four spatially distributed gauging stations and district wise wheat and rice yields data for the districts located within the basin. Simulation results showed an increase in mean annual rice yield in the range of 5.5-6.7, 16.6-20.2 and 26-33.4 % during 2020s, 2050s and 2080s, respectively. Similarly, mean annual wheat yield is also likely to increase by 13.9-15.4, 23.6-25.6 and 25.2-27.9 % for the same future time periods. Evapotranspiration for both wheat and rice is projected to increase in the range of 3-9.6 and 7.8-16.3 %, respectively. With increase in rainfall during rice growing season, irrigation water allocation for rice is likely to decrease (<5 %) in future periods, but irrigation water allocation for wheat is likely to increase by 17.0-45.3 % in future periods.

  6. Energy Balance of Irrigated Intercropping Field in the Middle Reaches of Heihe River Basin

    Institute of Scientific and Technical Information of China (English)

    WU Jinkui; DING Yongjian; WANG Genxu; SHEN Yongping; Yusuke YAMAZAKI; Jumpei KUBOTA

    2006-01-01

    Based on the experiments conducted in an irrigated intercropping field in Zhangye Oasis in the middle reaches of Heihe River basin in 2004, the characteristics of radiation budget are analyzed. Furthermore, energy balance is calculated by using Bowen-Ratio Energy Balance (BREB) method. The results show that the ratio of the absorbed radiation to the incoming short radiation in intercropping crop canopy-soil system is increasing with growing stages, from 0.81 in the initial growing stage (IGS) to 0.86 in the late growing stage (LGS). The net radiation, which is smaller in IGS, increases rapidly in the first period of the middle growing stage (MGS) and reaches the maximum value in the second period of MGS. It then somewhat decreases in LGS. The ratio of net radiation to total radiation has a similar trend with the net radiation. In the whole growing stages, latent heat flux, which takes up 70% or so of the net radiation, is the dominant item in energy balance. Sensible heat flux shares 20% of the net radiation and soil heat flux has a percentage of 10%. The characteristics of heat balance vary distinctly in different growing stages. In IGS, the ratios of latent heat flux,sensible heat flux and soil heat flux to net radiation are 44.5%, 23.8% and 31.7% respectively. In MGS, with the increasing of latent heat flux and the decreasing of sensible heat flux and soil heat flux, the ratios turn into 84.4%, 6.3% and 9.3%. In LGS, the soil heat flux maintains 0W/m2 or so, and latent heat flux and sensible heat flux take up 61.4% and 38.6% respectively. The energy balance also shows an obvious daily variation characteristic.

  7. EFFECTS OF THE CONSTRUCTION OF IRRIGATION RESERVOIRS ON THE DISTRIBUTION OF POLLUTANTS IN ESTUARINE ZONES OF SMALL MEDITERRANEAN RIVERS. THE CASE OF SPERCHIOS RIVER, GREECE

    Directory of Open Access Journals (Sweden)

    Manos Dassenakis

    2009-07-01

    Full Text Available Sperchios is a small river in central Greece and although its estuary has been characterised as an Important Bird Area and is included in the European network “NATURA 2000”, it is very poorly managed from an environmental point of view. The Sperchios basin is one of the most important agricultural regions in Greece but it is influenced also by industrial and urban pollution. An earthen dyke is erected b every summer about 2km upstream from the river mouth in order to collect the river water for irrigation purposes. The change in the site of the intermixing zone due to this fact affects the salinity of the water and the amount of suspended matter as well as the chemical behaviour and partitioning of both heavy metals and nutrients. The suspended matter was found to be the major carrier for most metals e.g. lead, zinc, copper whereas phosphorus was the limiting factor for the phytoplankton growth.

  8. Ground-water use, locations of production wells, and areas irrigated using ground water in 1998, middle Humboldt River basin, north-central Nevada

    Science.gov (United States)

    Plume, Russell W.

    2003-01-01

    In 1998, ground water was being pumped from about 420 production wells in the middle Humboldt River Basin for a variety of uses. Principal uses were for agriculture, industry, mining, municipal, and power plant purposes. This report presents a compilation of the number and types of production wells, areas irrigated by ground water, and ground-water use in 14 hydrographic areas of the middle Humboldt River Basin in 1998. Annual pumping records for production wells usually are reported to the Nevada Division of Water Resources. However, operators of irrigation wells are not consistently required to report annual pumpage. Daily power-consumption and pump-discharge rates measured at 20 wells during the 1998 irrigation season and total power use at each well were used to estimate the amount of water, in feet of depth, applied to 20 alfalfa fields. These fields include about 10 percent of the total area, 36,700 acres, irrigated with ground water in the middle Humboldt River Basin. In 1998 an average of 2.0 feet of water was applied to 14 fields irrigated using center-pivot sprinkler systems, and an average of 2.6 feet of water was applied to 6 fields irrigated using wheel-line sprinkler systems. A similar approach was used to estimate the amount of water pumped at three wells using pumps powered by diesel engines. The two fields served by these three wells received 3.9 feet of water by flood irrigation during the 1998 irrigation season. The amount of water applied to the fields irrigated by center-pivot and wheel-line irrigation systems during the 1998 irrigation season was less than what would have been applied during a typical irrigation season because late winter and spring precipitation exceeded long-term monthly averages by as much as four times. As a result, the health of crops was affected by over-saturated soils, and most irrigation wells were only used sporadically in the first part of the irrigation season. Power consumption at 19 of the 20 wells in the 1994

  9. Distribution of antibiotics in wastewater-irrigated soils and their accumulation in vegetable crops in the Pearl River Delta, southern China.

    Science.gov (United States)

    Pan, Min; Wong, Chris K C; Chu, L M

    2014-11-19

    Wastewater is increasingly being used to irrigate agricultural land in many countries around the world. However, limited research has examined the occurrence of antibiotics in soil irrigated with wastewater and their accumulation in plants. This study aimed to determine the distribution of various types of antibiotics in different environmental matrices in the Pearl River Delta (PRD) region and to evaluate their accumulation and translocation in edible crops. Samples were collected from six sites in the PRD where either domestic wastewater or fishpond water was used for irrigation. Results showed that fishpond water irrigated soils had higher concentrations of antibiotics than wastewater-irrigated soils. Different trends were observed in the accumulation of antibiotics in the different edible parts of various crops. Despite the low human annual exposure to antibiotics through the consumption of edible crops (1.10 to 7950 μg/y), the potential adverse effects of antibiotics along the food chain should not be neglected.

  10. Long term continuous field survey to assess nutrient emission impact from irrigated paddy field into river catchment

    Science.gov (United States)

    Kogure, Kanami; Aichi, Masaatsu; Zessner, Matthias

    2017-04-01

    In order to achieve good river environment, it is very important to understand and to control nutrient behavior such as Nitrogen and Phosphorus. As we could reduce impact from urban and industrial activities by wastewater treatment, pollution from point sources are likely to be controlled. Besides them, nutrient emission from agricultural activity is dominant pollution source into the river system. In many countries in Asia and Africa, rice is widely cultivated and paddy field covers large areas. In Japan 54% of its arable land is occupied with irrigated paddy field. While paddy field can deteriorate river water quality due to fertilization, it is also suggested that paddy field can purify water. We carried out field survey in middle reach of the Tone River Basin with focus on a paddy field IM. The objectives of the research are 1) understanding of water and nutrient balance in paddy field, 2) data collection for assessing nutrient emission. Field survey was conducted from June 2015 to October 2016 covering two flooding seasons in summer. In our measurement, all input and output were measured regarding water, N and P to quantify water and nutrient balance in the paddy field. By measuring water quality and flow rate of inflow, outflow, infiltrating water, ground water and flooding water, we tried to quantitatively understand water, N and P cycle in a paddy field including seasonal trends, and changes accompanied with rainy events and agricultural activities like fertilization. Concerning water balance, infiltration rate was estimated by following equation. Infiltration=Irrigation water + Precipitation - Evapotranspiration -Outflow We estimated mean daily water balance during flooding season. Infiltration is 11.9mm/day in our estimation for summer in 2015. Daily water reduction depth (WRD) is sum of Evapotranspiration and Infiltration. WRD is 21.5mm/day in IM and agrees with average value in previous research. Regarding nutrient balance, we estimated an annual N and

  11. 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.

  12. 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.

  13. 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. PMID:24171160

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-04-01

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

  15. Groundwater interaction with surface drains in the Ord River Irrigation Area, northern Australia: investigation by multiple methods

    Science.gov (United States)

    Smith, Anthony J.; Pollock, Daniel W.; Palmer, Duncan

    2010-08-01

    Following 35 years of persistent groundwater rise beneath northern Ivanhoe Plain in the Ord River Irrigation Area, northern Australia, the water table appears to have stabilized near the base of the irrigation surface-drain network. Hydrometric evidence indicates that intersection of the deepest surface drains by the rising water table simultaneously reduced aquifer recharge from surface-water infiltration and increased aquifer discharge by groundwater exfiltration. Water-table analysis supports the working hypothesis that the largest irrigation drain D4 on north Ivanhoe Plain has been receiving a significant amount of groundwater discharge since the mid-1990s. The rate of groundwater discharge to surface drains on north Ivanhoe Plain was estimated to be around 15-20 million (M)L/day based on groundwater-flow modelling. Groundwater tracing using radon and electrical conductivity indicated that groundwater discharge to drain D4 was ˜6-12 ML/day in August 2007. The rate of groundwater discharge was significantly larger where the drain traverses a very-permeable sand and gravel palaeochannel. Relatively modest exfiltration rates of order of magnitude tens to hundreds of mm/day into the drain were estimated to mitigate 0.5 m/year groundwater accretion for a land area of order of magnitude hundreds to thousands of ha.

  16. Future Water Resources Assessment for West African River Basins Under Climate Change, Population Growth and Irrigation Development

    Science.gov (United States)

    Wisser, D.; Ibrahim, B.; Proussevitch, A. A.

    2014-12-01

    West Africa economies rely on rain-fed agriculture and are extremely vulnerable to changes in precipitation. Results from the most recent generation of regional climate models suggest increases in rainy season rainfall variability (delayed rainy season onset, increased probability of dry spells, shorter rainy season duration) despite a moderate increase in rainy season total precipitation. These changes could potentially have detrimental effects on crop yield and food security. Additional pressures on water resources come from increased demand as a result of high population growth rates (~3% per year). Increased water storage and irrigation can help improve crop yields but future assessments of water resources are needed to prioritize irrigation development as an adaptation option. Increased water abstraction, in turn can impact water availability in downstream regions so that an integrated assessment of future water availability and demand is needed. We use a set of 15 RCM outputs from the CORDEX data archive to drive WBMplus, a hydrological model and simulate water availability under climate change. Based on estimated water constraints, we develop scenarios to expand irrigated areas (from the current 1% of all croplands) and calculate the effects on water scarcity, taking into account increased demand for domestic consumption and livestock water demand, at a spatial resolution of 10 km. Results around the 2050's indicate large potential to develop irrigated areas on ground and surface water and increase local water storage without increasing water scarcity downstream for many river basins in the region that could help alleviate pressures on the cropping systems and thereby increase food security.

  17. Heavy metal pollution in farmland irrigated with river water near a steel plant - detection by magnetic and geochemical methods

    Science.gov (United States)

    Zhang, C. X.

    2012-04-01

    The presence of heavy metals in the environment has become an increasing problem during the last several decades. It is a key scientific issue to disclose the source, degree and extent of pollution in farmland near to heavy industries. In this study the efficiency of magnetic methods for such a purpose is tested at a Chinese city (Loudi, Hunan Province) with fast developing steel industry. Lianshui River flows through the city and passes a large steel plant at the entrance of the urban area. Previous results revealed higher heavy metal contents in the vicinity of the Fe-smelting plant and in the city region[1]. Nearby farmland usually is irrigated with water from this river. We collected vertical soil profiles to about 60 cm depth within farmland nearby Lianshui River with sampling sites distributed from the upstream (before entering the city) to the downstream region (after leaving the city area). These samples were comprehensively investigated by integrating both magnetic and chemical analyses. Heavy metals (Pb, Zn, Cd etc) pollution in farmland soils in the downstream region is clearly higher than in the upstream region. Magnetic susceptibility and SIRM is correlating with heavy metals contents. The SIRM background in the upstream section of unpolluted farmland soils and river sediments is low (< 7-10-3Am2kg-1), whereas the polluted soils at the surrounding of the steel plant reveal higher SIRM intensities (30 to 40-10-3Am2kg-1) within the topmost 20 cm. SIRM in river sediments also correlates with heavy metals contents; it is strongly enhanced (80 to 200-10-3Am2kg-1) at the same sites, from surface to 40 cm deep depth. Magnetic enhancement is found to be related to the presence of spherical magnetite particles with a diameter of 10~30 μm. These findings demonstrate that magnetic methods have a convenient practical application for detecting and mapping heavy metal pollution in farmland soils irrigated by river water from nearby industrial areas. Reference 1

  18. Is irrigation water price an effective leverage for water management? An empirical study in the middle reaches of the Heihe River basin

    Science.gov (United States)

    Zhou, Qing; Wu, Feng; Zhang, Qian

    Serious water scarcity, low water-use efficiency, and over-exploitation of underground water have hindered socio-economic development and led to environmental degradation in the Heihe River basin, northwestern China. Price leveraging is an important tool in water demand management, and it is considered to be effective in promoting water conservation and improving water use efficiency on the premise that water demand is elastic. In the present study, we examine whether price is an effective and applicable instrument for restraining the increasing demand for agricultural irrigation water in the middle reaches of the Heihe River basin and how will it affect farmers' decisions on irrigation and crop structure. Specifically, the price elasticity of agricultural water demand was estimated based on the irrigation water demand function. The results show that the agricultural irrigation water price is statistically significant, but its elasticity is very low under current low water price. Price leverage cannot play a significant role in the context of the current pricing regime and farmers' response to price increase is intrinsically weak. To create incentives for conserving water and improving irrigation efficiency, price mechanism should be accompanied with clearly defined and legally enforceable water rights, restricted water quota measures, and reform of water authorities and water-user associations. Furthermore, increases of surface irrigation water price may lead to the over-withdrawal of groundwater, consequently, effective groundwater licensing and levying must take place to limit the total volume of groundwater withdrawal. In all, improving irrigation efficiency through better management and the adoption of water-saving technologies is the ultimate way to deal with the challenges facing irrigated agriculture in the middle reaches of the Heihe River basin.

  19. Heavy metal pollution in farmland irrigated with river water near a steel plant—magnetic and geochemical signature

    Science.gov (United States)

    Zhang, Chunxia; Appel, Erwin; Qiao, Qingqing

    2013-03-01

    The presence of heavy metals (HMs) in the environment is a major threat for humans. Magnetic proxies provide a rapid method for assessing the degree of HM pollution in environment. We have studied farmland soil irrigated with polluted river water in the vicinity of a steel plant in Loudi city (Hunan Province, China) to test the efficiency of magnetic methods for detecting the degree of HM pollution. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these farmland soils. Enhanced magnetic concentration values were found in the upper arable soil horizon (0-20 cm), which is related to the presence of spherical ˜10 to 30 μm sized magnetite particles. The spatial distribution of magnetic concentration and HM contents in the farmland soils matches with the spatial pattern of these parameters in river sediments. These findings provide evidence that HM pollution of the farmland soil is mainly caused by irrigation with wastewater. HMs Zn, Pb, Cu, Cd, Co, Ni, V are well correlate with magnetic susceptibility (χ). The pollution load index (PLI) of all nine anthropogenic HMs (including also Cr and Mo) and log10(χ) are significantly correlated. Using the resulting linear PLI-log10(χ) function, values of χ can serve as a convenient tool for semi-quantifying the degree of HM pollution in the uppermost ˜20 cm of the studied farmland soils. These findings suggest that magnetic methods can generally serve as a convenient tool for detecting and mapping HM pollution in farmland soil irrigated with wastewater from sites nearby heavy industrial activities.

  20. Beneficial uses of geothermal energy description and preliminary results for phase 1 of the Raft River irrigation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, R.C.; Spencer, S.G.

    1977-01-01

    The first phase of an experiment using geothermal water for irrigation is described and preliminary results are discussed. The water was from a moderate temperature well, having salinity of about 2000 ppM, and is considered characteristic of the types of geothermal fluids that will be obtained from the young volcanic/young sediment formations of the northern intermountain west. The activity was completed at a location adjacent to ERDA's Raft River Geothermal Project in southern Idaho. About 12.5 acres, of which part had no previous cultivation, were subdivided by crops and irrigation practices for investigation with the geothermal water and a control comparison water from the relatively pure Raft River. Flood and sprinkler application techniques were used and wheat, barley, oats, grasses, alfalfa, potatoes, and garden vegetables were successfully grown. An accompanying experiment evaluated the behavior of an established alfalfa crop located nearby, when most of the irrigation water was geothermal. The experiment addressed heavy metal uptake in plants, plant fluoride retention and damage, plant tolerances to salts, soil alterations and other behavior as a result of the geothermal fluids, all of which were largely believed to eliminate geothermal water from contention for crop growing utilization. Not all analyses and results are complete in this reporting, but first results indicate no apparent difference between the geothermal watered crops and those obtained using the fresh water control. Extensive chemical analyses, neutron activation analyses, and other evaluations of crop samples are discussed, and some of the findings are presented. Although evaluation of crop yields was not an objective, extrapolations from samples indicate that yield results were comparable to those commonly found in the area, and the yield varied little between water sources. (JGB)

  1. Modeling of basin-wide water management for dry-season paddy irrigation with large reservoirs in the Mekong River Basin

    Science.gov (United States)

    Kudo, R.; Masumoto, T.; Horikawa, N.; Yoshida, T.

    2012-12-01

    Northeast Thailand, one of the regions in the Mekong River Basin, has less rainfall than adjacent countries and its rainfall is heavily concentrated in rainy seasons (almost 90% of annual rainfall). Therefore, this area is characterized as semi-arid region especially during dry seasons. In this region, rain-fed paddies account for about 90% and this leads to unstable rice production. Against these backgrounds, a number of large irrigation projects have been carried out since the 1970s to increase agricultural productivity. In these projects, a lot of irrigation facilities such as large/medium reservoirs, diversion weirs and irrigation canals were constructed for stable water supply in dry seasons. These projects enable farmers to pursue double rice cropping as rainy- and dry-season cropping in this region. Paddy field irrigation, however, exerts a great influence on water circulation of river basins in Monsoon Asia and modeling of these processes is crucial to understand the hydrological cycle especially in areas where irrigated agriculture is dominant. In this study, to quantify the hydrological cycle in irrigation-dominant basins, we applied a distributed hydrological model incorporating paddy irrigation schemes to the Mun River Basin, one of the tributaries of the Mekong River, in Northeast Thailand, and analyzed water circulation considering complex water use by agricultural activities. The model used in this study consists of four sub-models, such as referential evapotranspiration, cropping pattern/area, agricultural water use, and runoff model in order to estimate various information on agricultural water use. Additionally, water allocation and reservoir operation models were integrated into the hydrological model to account for the water circulation in large irrigation areas. For the analysis, the basin is divided into 10km-mesh and each mesh contains the ratio of 5 land-use category as forest, rain-fed paddy, irrigated paddy, upland field and water area

  2. Glacial Lake Outburst Flood Risk in the Poiqu/Bhote Koshi/Sun Koshi River Basin in the Central Himalayas

    Directory of Open Access Journals (Sweden)

    Narendra Raj Khanal

    2015-11-01

    Full Text Available The Himalayas have experienced several glacial lake outburst floods (GLOFs, and the risk of GLOFs is now increasing in the context of global warming. Poiqu watershed in the Tibet Autonomous Region, China, also known as the Bhote Koshi and Sun Koshi downstream in Nepal, has been identified as highly prone to GLOFs. This study explored the distribution of and changes in glacial lakes, past GLOFs and the resulting losses, risk from potential future GLOFs, and risk reduction initiatives within the watershed. A relationship was established between lake area and volume of lake water based on data from 33 lakes surveyed within the Hindu Kush Himalayan region, and the maximum possible discharge was estimated using this and other previously developed empirical equations. We recommend different strategies to reduce GLOF risk and highlight the need for a glacial lake monitoring and early-warning system. We also recommend strong regional cooperation, especially on issues related to transboundary rivers.

  3. Assessing options to increase water productivity in irrigated river basins using remote sensing and modelling tools

    NARCIS (Netherlands)

    Dam, van J.C.; Singh, R.; Bessembinder, J.J.E.; Leffelaar, P.A.; Bastiaanssen, W.G.M.; Jhorar, R.K.; Kroes, J.G.; Droogers, P.

    2006-01-01

    In regions where water is more scarce than land, the water productivity concept (e.g. crop yield per unit of water utilized) provides a useful framework to analyse crop production increase or water savings in irrigated agriculture. Generic crop and soil models were applied at field and regional

  4. Assessing options to increase water productivity in irrigated river basins using remote sensing and modelling tools

    NARCIS (Netherlands)

    Dam, van J.C.; Singh, R.; Bessembinder, J.J.E.; Leffelaar, P.A.; Bastiaanssen, W.G.M.; Jhorar, R.K.; Kroes, J.G.; Droogers, P.

    2006-01-01

    In regions where water is more scarce than land, the water productivity concept (e.g. crop yield per unit of water utilized) provides a useful framework to analyse crop production increase or water savings in irrigated agriculture. Generic crop and soil models were applied at field and regional scal

  5. Quantifying seepage using heat as a tracer in selected irrigation canals, Walker River Basin, Nevada, 2012 and 2013

    Science.gov (United States)

    Naranjo, Ramon C.; Smith, David W.

    2016-11-16

    The Walker River is an important source of water for western Nevada. The river provides water for agriculture and recharge to local aquifers used by several communities. Farmers began diverting water from the Walker River in the 1860s to support growing agricultural development. Over time, the reduced inflows into Walker Lake from upstream reservoirs and diversions have resulted in 170 feet of lake level decline and increased dissolved-solids concentrations to levels that threaten aquatic ecosystems, including survival of Lahonton cutthroat trout, a native species listed in the Endangered Species Act. Investigations of the water-budget components in the Walker River Basin have revealed uncertainty in the recharge to aquifers from irrigation canals. To address this need, the U.S. Geological Survey conducted an extensive field study from March 2012 through October 2013 to quantify seepage losses in selected canals in the Smith Valley, Mason Valley, and Walker Lake Valley irrigation areas.The seepage rates estimated for the 2012 and 2013 irrigation seasons in the Smith Valley transect sites (Saroni and Plymouth canals) ranged between 0.01 to 2.5 feet per day (ft/d) (0.01 to 0.68 cubic feet per second per mile [ft3/s-mi]). From 2012 to 2013, the average number of days the canals had flowing water decreased from 190 to 125 due to drier climate and lack of water available for diversion from the Walker River. The nearly 50-percent reductions in volumetric loss rates between 2012 and 2013 were associated with less than average diversions into canals from the Walker River and reductions in infiltration rates following routine canal maintenance.Models developed for the Saroni canal in 2012 were recalibrated in 2013 to evaluate changes in seepage as a result of siltation. Just prior to the 2012 irrigation season, nearly the entire length of the canal was cleared of vegetation and debris to improve flow conveyance. In 2013, following the first year of maintenance, a 90-percent

  6. Turkish Children's Drawing of Nature in a Certain Way: Range of Mountains in the Back, the Sun, Couple of Clouds, a River Rising from the Mountains

    Science.gov (United States)

    Ulker, Riza

    2012-01-01

    This study reveals that Turkish kindergarten through 8th Grade (K-8) students draw nature pictures in a certain way; range of mountains in the background, a sun, a couple of clouds, a river rising from the mountains. There are similarities in the K-8 students' nature drawings in the way these nature items are organized on a drawing paper. We…

  7. Relationships Among Drip Irrigation Amount, Irrigation Interval and Deep Percolation:A Case Study on Manas River Oasis, Xinjiang%干旱区滴灌棉田灌水量与灌溉周期关系

    Institute of Scientific and Technical Information of China (English)

    孙林; 罗毅; 杨传杰; 张艳; 来剑斌; 吉力力·阿不都外力

    2012-01-01

    Drip irrigation has been developing rapidly in Xinjiang in the last two decades because of its high water use efficiency. However, salinity accumulation caused by drip irrigation is an important issue to be considered in irrigation management. The amount of proper irrigation water (Q), irrigation interval (T), and deep percolation (L) are fundamentals of efficient drip irrigation management and soil salinity control. Revelation of the complicated relationships among them through field experiment is both time consuming and costly. In this paper, a Q-T-L relationship was derived through combining numerical simulations of drip irrigation with HYDRUS-2D model and field experiments in the Manas River oasis of Xinjiang. And the relationship can be used as a guide for irrigation practice. During the simulation, uncertainty of predicting crop evapotranspiration was simulated by the Markov chain approach.The Q-T-L curves present general, non-linear relationships among irrigation water amount, irrigation interval and deep percolation. The irrigation interval increases with Q in each irrigation application, and percolation increases with irrigation water amount. Three important threshold points on the curve should be noted: deep percolation occurs when the amount of irrigation water exceeds 35 mm in depth in 5 days intervals; when the amount of water exceeds 65 mm per irrigation, the irrigation interval increase slows down while deep percolation speeds up; Irrigation intervals are not supposed to exceed 12 days because of the amount water being irrigated and the significant percolation. From these threshold points, we can conclude the guideline of irrigation methods. With water use efficiency as the first priority, irrigation water amount should be no more than 35 mm with an irrigation interval of less than 5 days. With a longer irrigation interval as a priority, irrigation water amount should be no more than 120 mm and the irrigation interval should be less

  8. 宁夏引黄灌区智能节水灌溉模式与技术研究%Research on Intelligent Saving Irrigation Mode and Technology for Yellow River Irrigation Area in Ningxia

    Institute of Scientific and Technical Information of China (English)

    赵伶俐; 王福平

    2015-01-01

    To solve the shortcoming of serious water resources waste because of using the long and heavy traditional irrigation mode in Yellow River irrigation area in Ningxia,this paper proposes and designs a scheme that uses networking,sensor and wireless data communication technology.The intelligent water saving irrigation system realizes sensing soil moisture with wireless sensor,real-time collecting water level parameters,monitoring flow velocity parameters and calculating the water quantity,transmitting the data through the wireless network to control irrigation system valve open or close.It can timely and moderately irrigate to realize the ac-curate saving irrigation mode of remote-controlled irrigation system.%针对宁夏引黄灌区传统大灌大排的灌溉模式,提出根据土壤湿度适时、适量合理的灌溉原则,设计利用传感器、无线通信技术、自动监控、物联网等技术的精准节水灌溉系统.通过传感器感应土壤水分,实时采集用水量、水位参数,无线通信网络传输数据,程序阈值设置土壤含水率、空气湿度等参数策略,控制灌溉系统的水泵自动开启与关闭,实现一种远程监控用水量的智能节水灌溉模型.

  9. 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.

  10. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Artificial Drainage (1992) and Irrigation (1997)

    Science.gov (United States)

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated area of artifical drainage for the year 1992 and irrigation types for the year 1997 compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data sets were derived from tabular National Resource Inventory (NRI) data sets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 2000). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, U.S. Geological Survey, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others, 2007). The MRB_E2RF1 catchments are based on a modified

  11. More Water Resources but Less for Irrigation: Adaptation Strategy of the Yellow River in a Changing Environment

    Science.gov (United States)

    Tang, Q.; Yin, Y. Y.

    2015-12-01

    The Yellow River is the primary source of freshwater to the northern China. Increasing population and socio-economic development have put great pressure on water resources of the river basin. The anticipated climate and socio-economic changes may further increase water stress. Development of adaptation strategies would have significant implications for water and food security of this region. In this study, the outputs of multiple hydrological models forced with the bias-corrected climatic variables from multiple global climate models were used to assess the change in renewable water resources of the river basin in the 21st century. The outputs of multiple crop models were used to assess the change in agricultural water demand. The domestic and industrial water demands were estimated based on the future socio-economic conditions under the Shared Socio-economic Pathways (SSPs). Besides basic ecosystem needs for water which must be met, the water use in domestic and industrial sectors is considered to have a higher priority than the agricultural water use when water is insufficient. The results show that the renewable water resources of the basin would increase as global mean temperature increases while the water demand would grow much more rapidly, largely due to water demand increase in domestic and industrial sectors. In most of the sub-basins of the Yellow River basin, the available water resources can not sustain all the water use sectors starting from the next a few decades. As more water resources would be appropriated by domestic and industrial sectors, a part of irrigated area had to be converted to rainfed agriculture which led to a large reduction in food production. This study highlights the linked water and food security in a changing environment and suggests that the trade-off should be considered when developing regional adaptation strategies.

  12. Diverse Land Use and the Impact on (Irrigation Water Quality and Need for Measures — A Case Study of a Norwegian River

    Directory of Open Access Journals (Sweden)

    Gro S. Johannessen

    2015-06-01

    Full Text Available Surface water is used for irrigation of food plants all over the World. Such water can be of variable hygienic quality, and can be contaminated from many different sources. The association of contaminated irrigation water with contamination of fresh produce is well established, and many outbreaks of foodborne disease associated with fresh produce consumption have been reported. The objective of the present study was to summarize the data on fecal indicators and selected bacterial pathogens to assess the level of fecal contamination of a Norwegian river used for irrigation in an area which has a high production level of various types of food commodities. Sources for fecal pollution of the river were identified. Measures implemented to reduce discharges from the wastewater sector and agriculture, and potential measures identified for future implementation are presented and discussed in relation to potential benefits and costs. It is important that the users of the water, independent of intended use, are aware of the hygienic quality and the potential interventions that may be applied. Our results suggest that contamination of surface water is a complex web of many factors and that several measures and interventions on different levels are needed to achieve a sound river and safe irrigation.

  13. Groundwater Dynamics under Water Saving Irrigation and Implications for Sustainable Water Management in an Oasis: Tarim River Basin of Western China

    Science.gov (United States)

    Zhang, Z.; Hu, H.; Tian, F.; Yao, X.; Sivapalan, M.

    2014-02-01

    Water is essential for life. Specifically in the oases of inland arid basins, water is a critically limited resource, essential for the development of socio-economy and sustainability of eco-environmental systems. Due to the unique hydrological regime present in arid oases, a moderate groundwater table is the goal of sustainable water management. A shallow water table induces serious secondary salinization and collapse of agriculture, while a deep water table causes deterioration of natural vegetation. From the hydrological perspective, the exchange flux between unsaturated vadose zone and groundwater reservoir is a critical link to understand regional water table dynamics. This flux is substantially influenced by anthropogenic activities. In Tarim River Basin of western China, where agriculture consumes over 90% of available water resources, the exchange flux is influenced strongly by irrigation. Recently, mulched drip irrigation, a very advanced water-saving irrigation method, has been widely applied in the Tarim River Basin, which greatly impacted the exchange flux and thus the regional groundwater dynamics. Capitalizing on recent progress in evaporation measurement techniques, we can now close the water balance and directly quantify the exchange flux at the field scale, thus gain a better understanding of regional groundwater dynamics. In this study, comprehensive observations of water balance components in an irrigated cropland were implemented in 2011 and 2012 in a typical oasis within Tarim River Basin. The water balance analysis showed that the exchange flux and groundwater dynamics were significantly altered by the application of water-saving irrigation. The exchange flux is mostly downward (310.5 mm yr-1), especially during drip irrigation period and spring flush period, while the upward flux is trivial (-16.1 mm yr-1) due to the moderate groundwater table depth (annual average depth 2.9 m). Traditional secondary salinization caused by intense phreatic

  14. Groundwater dynamics under water-saving irrigation and implications for sustainable water management in an oasis: Tarim River basin of western China

    Science.gov (United States)

    Zhang, Z.; Hu, H.; Tian, F.; Yao, X.; Sivapalan, M.

    2014-10-01

    Water is essential for life. Specifically in the oases of inland arid basins, water is a critically limited resource, essential for the development of the socio-economy and the sustainability of eco-environmental systems. Due to the unique hydrological regime present in arid oases, a moderate groundwater table is the goal of sustainable water management. A shallow water table induces serious secondary salinization and collapse of agriculture, while a deep water table causes deterioration of natural vegetation. From the hydrological perspective, the exchange flux between the unsaturated vadose zone and groundwater reservoir is a critical link to understanding regional water table dynamics. This flux is substantially influenced by anthropogenic activities. In the Tarim River basin of western China, where agriculture consumes over 90% of available water resources, the exchange flux between the unsaturated vadose zone and groundwater reservoir is influenced strongly by irrigation. Recently, mulched drip irrigation, a sophisticated water-saving irrigation method, was widely applied in the Tarim River basin, which greatly impacted the exchange flux and thus the regional groundwater dynamics. Capitalizing on recent progress in evaporation measurement techniques, we can now close the water balance and directly quantify the exchange flux at the field scale, thus gaining a better understanding of regional groundwater dynamics. In this study, comprehensive observations of water balance components in an irrigated cropland were implemented in 2012 and 2013 in a typical oasis within the Tarim River basin. The water balance analysis showed that the exchange flux and groundwater dynamics were significantly altered by the application of water-saving irrigation. The exchange flux at the groundwater table is mostly downward (310.5 mm year-1), especially during drip irrigation period and spring flush period, while the upward flux is trivial (16.1 mm year-1) due to the moderate

  15. "Preliminary Evaluation of Climate Change impact in the Codegua's River Irrigation Improvement Project"

    Science.gov (United States)

    Ricchetti, Franco; Vargas, Ximena

    2017-04-01

    The aim of this study is to quantify the impact of Climate Change in one of the projected dams for farming activities in Codegua's catchment, near to Santiago, Chile. This reservoir is one of the twenty that will be built by the Hydraulics Infrastructure Management Department of Chile in the next years. The design is based on the concept of "Irrigation Security", defined as the quotient between the number of years where is possible to deliver the crop demand and the total of years. It must be greater than 85% to approve the project. The evaluation of Climate Change is based in two scenarios: RCP 4.5 and RCP 8.5. The forecast hydroclimatology is based in General Circulation Model MPI-ESM, from Max Planck Institute, Germany. The evaluation considers two future periods: a near future (2020-2055) and a further future (2065-2100). First, statistical downscaling of precipitation and temperature time series are made and then the yearly inflow to the dam is estimated by a simple rainfall-runoff relation, the future evapotranspiration is estimated by Penman-Monteith method and with an empirical mathematical relation, based in Blaney and Criddle method. For this reason, the analysis included additional scenarios to incorporate the uncertainty in the evapotranspiration estimation as well as on tributary volumes from the basin to the dam, for each Climate Change scenarios. Climate Change in the zone of study indicates that precipitations will be lower than the present and the temperature will increase. For example, the results predict that precipitation in the best scenario, for near future, will go down 15% and temperature will increase in 0.6 (°C). For the further future in the worst scenarios, model predicts that precipitation will go down around 30% and temperature will increase 2.5 (°C). This coupled effects modify in a great way the water supply and demand in the zone of study. With the new hydrology forecast for the future, the "Irrigation Security" is recalculated in

  16. Influence of groundwater on the degradation of irrigated soils in a semi-arid region, the inner delta of the Niger River, Mali

    Science.gov (United States)

    Valenza, A.; Grillot, J. C.; Dazy, J.

    2000-08-01

    The problem of soil degradation through alkalinization/salinization in an irrigated area with a semi-arid climate was examined in the inner delta of the Niger River, Mali, by the study of groundwater hydraulics and hydrochemistry in an area recharged by irrigation water. On the basis of data analysis on various scales, it is concluded that the current extent of the surface saline soils is due to a combination of three factors: (1) the existence of ancient saline soils (solonchaks) resulting from the creation of a broad sabkha west of the former course of the Niger River, now called the Fala of Molodo. These saline crusts were gradually deposited during the eastward tilting of the tectonic block that supports the Niger River; (2) the irrigation processes during the recent reflooding of the Fala of Molodo (river diversion in 1950). These used very poorly mineralized surface water but reintroduced into the alluvial groundwater system - generally of a low permeability (K=10-6 m s-1) - salts derived from the ancient solonchaks; and (3) the redeposition of the dissolved salts on the surface due to the intense evapotranspiration linked to the present Sahelian climate. In this context, only efficient artificial draining of subsurface alluvial groundwater can eliminate most of the highly mineralized flow and thus reduce the current saline deposits.

  17. 黄河冲积平原灌溉入渗研究%Research on the Irrigation Infiltration in the Yellow River Alluvial Plain

    Institute of Scientific and Technical Information of China (English)

    谭菊萍

    2013-01-01

    黄河冲积平原面积广大,农田灌溉频繁,灌水量大,在地下水资源评价时对灌溉入渗系数取值困难。本文在现场灌溉入渗试验的基础上,分析包气带岩性及结构、水位埋深、灌溉水量对灌溉入渗系数的影响,总结提出了多种条件下灌溉入渗系数的取值范围。在单位灌水量40~60 m3/亩和水位埋深小于4 m、4~8 m、大于8 m的井灌区中,当包气带岩性为粉土、粉砂时,灌溉入渗系数可分别取值0.21~0.10、0.10~0.05、0.05~0;当包气带岩性夹有粉质粘土层时,灌溉入渗系数可分别取值0.15~0.09、0.09~0.05、0.05~0。在单位灌水量较大的渠灌区,灌溉入渗系数可按单位灌水量的增大倍数而增加,由此为黄河冲积平原区地下水补给量计算中灌溉入渗系数的确定提供了依据。%The Yellow River alluvial plain is a large area, whose farmland irrigation is very frequency that wasted a large amount of water. It is hard to obtain irrigation infiltration coefficient values when the groundwater resourc-es are evaluated. In this paper, on the basis of the field irrigation infiltration test, the lithology, structure, water lev-el, and irrigation water in the vadose zone impacting on the irrigation infiltration coefficient was summarized, and the range of irrigation infiltration coefficient on various conditions is proposed. In the well irrigated area, the unit of irrigation water is 240~360 m3 per acre and the groundwater level range is8 m. If there is floury soil and silt in the vadose zone, the value rang of irrigation coefficient infiltration is 0.21~0.10、0.10~0.05、0.05~0, respectively;If it mixed with silty clay layer in the vadose zone, the value rang of irrigation coeffi-cient infiltration is 0.15~0.09、0.09~0.05、0.05~0, respectively. In the canal irrigation district where the unit of irrigation is big, irrigation coefficient infiltration is increased with the multiple

  18. Risk of Illness with Salmonella due to Consumption of Raw Unwashed Vegetables Irrigated with Water from the Bogotá River.

    Science.gov (United States)

    Henao-Herreño, Laura X; López-Tamayo, Ana M; Ramos-Bonilla, Juan P; Haas, Charles N; Husserl, Johana

    2016-06-27

    The Bogotá River receives untreated wastewater from the city of Bogotá and many other towns. Downstream from Bogotá, water from the river is used for irrigation of crops. Concentrations of indicator organisms in the river are high, which is consistent with fecal contamination. To investigate the probability of illness due to exposure to enteric pathogens from the river, specifically Salmonella, we took water samples from the Bogotá River at six sampling locations in an area where untreated water from the river is used for irrigation of lettuce, broccoli, and cabbage. Salmonella concentrations were quantified by direct isolation and qPCR. Concentrations differed, depending on the quantification technique used, ranging between 10(7.7) and 10(9.9) number of copies of gene invA per L and 10(5.3) and 10(8.4) CFU/L, for qPCR and direct isolation, respectively. A quantitative microbial risk assessment model that estimates the daily risk of illness with Salmonella resulting from consuming raw unwashed vegetables irrigated with water from the Bogotá River was constructed using the Salmonella concentration data. The daily probability of illness from eating raw unwashed vegetables ranged between 0.62 and 0.85, 0.64 and 0.86, and 0.64 and 0.85 based on concentrations estimated by qPCR (0.47-0.85, 0.47-0.86, and 0.41-0.85 based on concentrations estimated by direct isolation) for lettuce, cabbage, and broccoli, respectively, which are all above the commonly propounded benchmark of 10(-4) per year. Results obtained in this study highlight the necessity for appropriate wastewater treatment in the region, and emphasize the importance of postharvest practices, such as washing, disinfecting, and cooking.

  19. Has irrigated water from Mahaweli River contributed to the kidney disease of uncertain etiology in the dry zone of Sri Lanka?

    Science.gov (United States)

    Diyabalanage, Saranga; Abekoon, Sumith; Watanabe, Izumi; Watai, Chie; Ono, Yuko; Wijesekara, Saman; Guruge, Keerthi S; Chandrajith, Rohana

    2016-06-01

    The Mahaweli is the largest river basin in Sri Lanka that provides water to the dry zone region through multipurpose irrigation schemes . Selenium, arsenic, cadmium, and other bioimportant trace elements in surface waters of the upper Mahaweli River were measured using ICP-MS. Trace element levels were then compared with water from two other rivers (Maha Oya, Kalu Ganga) and from six dry zone irrigation reservoirs. Results showed that the trace metal concentrations in the Mahaweli upper catchment were detected in the order of Fe > Cu > Zn > Se > Cr > Mn > As > Ni > Co > Mo. Remarkably high levels of Ca, Cr, Co, Ni, Cu, As, and Se were observed in the Mahaweli Basin compared to other study rivers. Considerably high levels of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, and Se were found in upstream tributaries of the Mahaweli River. Such metals possibly originated from phosphate and organic fertilizers that are heavily applied for tea and vegetable cultivations within the drainage basin. Cadmium that is often attributed to the etiology of unknown chronic kidney diseases in certain parts of the dry zone is much lower than previously reported levels. Decrease in these metals in the lower part of the Mahaweli River could be due to adsorption of trace metals onto sediment and consequent deposition in reservoirs.

  20. A Simple Scheme for Modeling Irrigation Water Requirements at the Regional Scale Applied to an Alpine River Catchment

    Directory of Open Access Journals (Sweden)

    Pascalle C. Smith

    2012-11-01

    Full Text Available This paper presents a simple approach for estimating the spatial and temporal variability of seasonal net irrigation water requirement (IWR at the catchment scale, based on gridded land use, soil and daily weather data at 500 × 500 m resolution. In this approach, IWR is expressed as a bounded, linear function of the atmospheric water budget, whereby the latter is defined as the difference between seasonal precipitation and reference evapotranspiration. To account for the effects of soil and crop properties on the soil water balance, the coefficients of the linear relation are expressed as a function of the soil water holding capacity and the so-called crop coefficient. The 12 parameters defining the relation were estimated with good coefficients of determination from a systematic analysis of simulations performed at daily time step with a FAO-type point-scale model for five climatically contrasted sites around the River Rhone and for combinations of six crop and ten soil types. The simple scheme was found to reproduce well results obtained with the daily model at six additional verification sites. We applied the simple scheme to the assessment of irrigation requirements in the whole Swiss Rhone catchment. The results suggest seasonal requirements of 32 × 106 m3 per year on average over 1981–2009, half of which at altitudes above 1500 m. They also disclose a positive trend in the intensity of extreme events over the study period, with an estimated total IWR of 55 × 106 m3 in 2009, and indicate a 45% increase in water demand of grasslands during the 2003 European heat wave in the driest area of the studied catchment. In view of its simplicity, the approach can be extended to other applications, including assessments of the impacts of climate and land-use change.

  1. Evaluation and comparison of methods to estimate irrigation withdrawal for the National Water Census Focus Area Study of the Apalachicola-Chattahoochee-Flint River Basin in southwestern Georgia

    Science.gov (United States)

    Painter, Jaime A.; Torak, Lynn J.; Jones, John W.

    2015-09-30

    Methods to estimate irrigation withdrawal using nationally available datasets and techniques that are transferable to other agricultural regions were evaluated by the U.S. Geological Survey as part of the Apalachicola-Chattahoochee-Flint (ACF) River Basin focus area study of the National Water Census (ACF–FAS). These methods investigated the spatial, temporal, and quantitative distributions of water withdrawal for irrigation in the southwestern Georgia region of the ACF–FAS, filling a vital need to inform science-based decisions regarding resource management and conservation. The crop– demand method assumed that only enough water is pumped onto a crop to satisfy the deficit between evapotranspiration and precipitation. A second method applied a geostatistical regimen of variography and conditional simulation to monthly metered irrigation withdrawal to estimate irrigation withdrawal where data do not exist. A third method analyzed Landsat satellite imagery using an automated approach to generate monthly estimates of irrigated lands. These methods were evaluated independently and compared collectively with measured water withdrawal information available in the Georgia part of the ACF–FAS, principally in the Chattahoochee-Flint River Basin. An assessment of each method’s contribution to the National Water Census program was also made to identify transfer value of the methods to the national program and other water census studies. None of the three methods evaluated represent a turnkey process to estimate irrigation withdrawal on any spatial (local or regional) or temporal (monthly or annual) extent. Each method requires additional information on agricultural practices during the growing season to complete the withdrawal estimation process. Spatial and temporal limitations inherent in identifying irrigated acres during the growing season, and in designing spatially and temporally representative monitor (meter) networks, can belie the ability of the methods to

  2. 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.

  3. Carbon Dioxide Emissions as Affected by Alternative Long-Term Irrigation and Tillage Management Practices in the Lower Mississippi River Valley

    Directory of Open Access Journals (Sweden)

    S. F. Smith

    2014-01-01

    Full Text Available Ensuring the sustainability of cultivated soils is an ever-increasing priority for producers in the Lower Mississippi River Valley (LMRV. As groundwater sources become depleted and environmental regulations become more strict, producers will look to alternative management practices that will ensure the sustainability and cost-effectiveness of their production systems. This study was conducted to assess the long-term (>7 years effects of irrigation (i.e., irrigated and dryland production and tillage (conventional and no-tillage on estimated carbon dioxide (CO2 emissions from soil respiration during two soybean (Glycine max L. growing seasons from a wheat- (Triticum aestivum L.- soybean, double-cropped production system in the LMRV region of eastern Arkansas. Soil surface CO2 fluxes were measured approximately every two weeks during two soybean growing seasons. Estimated season-long CO2 emissions were unaffected by irrigation in 2011 (P>0.05; however, during the unusually dry 2012 growing season, season-long CO2 emissions were 87.6% greater (P=0.044 under irrigated (21.9 Mg CO2 ha−1 than under dryland management (11.7 Mg CO2 ha−1. Contrary to what was expected, there was no interactive effect of irrigation and tillage on estimated season-long CO2 emissions. Understanding how long-term agricultural management practices affect soil respiration can help improve policies for soil and environmental sustainability.

  4. Effects of Irrigation and Rainfall on the Population Dynamics of Rift Valley Fever and Other Arbovirus Mosquito Vectors in the Epidemic-Prone Tana River County, Kenya.

    Science.gov (United States)

    Sang, R; Lutomiah, J; Said, M; Makio, A; Koka, H; Koskei, E; Nyunja, A; Owaka, S; Matoke-Muhia, D; Bukachi, S; Lindahl, J; Grace, D; Bett, B

    2017-03-01

    Rift Valley fever (RVF) is a mosquito-borne viral zoonosis that is found in most regions of sub-Saharan Africa, and it affects humans, livestock, and some wild ungulates. Outbreaks are precipitated by an abundance of mosquito vectors associated with heavy persistent rainfall with flooding. We determined the impact of flood-irrigation farming and the effect of environmental parameters on the ecology and densities of primary and secondary vectors of the RVF virus (RVFV) in an RVF-epidemic hotspot in the Tana River Basin, Kenya. Mosquito sampling was conducted in farms and villages (settlements) in an irrigated and a neighboring nonirrigated site (Murukani). Overall, a significantly higher number of mosquitoes were collected in farms in the irrigation scheme compared with villages in the same area (P mosquito densities, particularly the primary vectors. Adult floodwater mosquitoes and Mansonia spp. were collected indoors; immatures of Ae. mcintoshi and secondary vectors were collected in the irrigation drainage canals, whereas those of Ae. ochraceous and Aedes sudanensis Theobald were missing from these water bodies. In conclusion, irrigation in RVF endemic areas provides conducive resting and breeding conditions for vectors of RVFV and other endemic arboviruses. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

  5. Towards Quantifying The Economic Effects Of Poor And Fluctuating Water Quality On Irrigation Agriculture: A Case Study Of The Lower Vaal And Riet Rivers

    OpenAIRE

    Armour, R.J.; Viljoen, Machiel F.

    2000-01-01

    Irrigation farmers in the lower reaches of the Vaal and Riet Rivers are experiencing substantial yield reductions in certain crops and more profitable crops have been withdrawn from production, hypothesised, as a result of generally poor but especially fluctuating water quality. In this paper secondary data is used in a linear programming model to test this hypothesis by calculating the potential loss in farm level optimal returns. The model is static with a time frame of two production seaso...

  6. Processes at Water Intake from Mountain Rivers into Hydropower and Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Vatin Nikolai

    2016-01-01

    Full Text Available In paper, researches of riverbed and hydraulic processes at the water intake from mountain rivers are observed. Classification of designs of the mountain water intake structures, based on continuity signs is offered. Perfecting of base designs of water intake structures of a mountain-foothill zone and means of their hydraulic automation is carried out. The technological, theoretical and experimental substantiation of parameters of basic elements of these designs with a glance of hydromorphometric characteristics of the mountain rivers is given. Complex hydraulic researches of kinematic characteristics and carrying ability of a two-phase stream on water intake structures are executed. Bases of a technique of engineering calculation of the offered designs of water intake structures and the recommendation of their designing and maintenance in various hydrological regimes are developed.

  7. Processes at Water Intake from Mountain Rivers into Hydropower and Irrigation Systems

    OpenAIRE

    Vatin Nikolai; Lavrov Nikolai; Loginov Gennadi

    2016-01-01

    In paper, researches of riverbed and hydraulic processes at the water intake from mountain rivers are observed. Classification of designs of the mountain water intake structures, based on continuity signs is offered. Perfecting of base designs of water intake structures of a mountain-foothill zone and means of their hydraulic automation is carried out. The technological, theoretical and experimental substantiation of parameters of basic elements of these designs with a glance of hydromorphome...

  8. Applying SDDP to very large hydro-economic models with a simplified formulation for irrigation: the case of the Tigris-Euphrates river basin.

    Science.gov (United States)

    Rougé, Charles; Tilmant, Amaury

    2015-04-01

    extended to any type of consumptive use of water beyond irrigation, e.g., municipal, industrial, etc This slightly different version of SDDP is applied to a large portion of the Tigris-Euphrates river basin. It comprises 24 state variables representing storage in reservoirs, 28 hydrologic state variables, and 51 demand nodes. It is the largest yet to simultaneously consider hydropower and irrigation within the same river system, and the proposed formulation almost halves the number of state variables to be considered.

  9. 波涌流灌在山东引黄灌区冬小麦机井灌中的应用%Experimental Research on Surge Irrigation Applied to Well Irrigation of Winter Wheat in Yellow River Irrigation Area of Shandong Province

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    This test used the original pumped well irrigation facilities to irrigate the border check of general specification (3 m × 95 m) with surge irrigation system in Yellow River irrigation area of Shandong Province .And we compared the surge irrigation water flow propulsion ,change of soil water content and water use efficiency of winter wheat with continuous irrigation .Under the test condi‐tion ,the results showed that the second period of surge irrigation which had two periods and whose water-saving rate was 10% was 1 .85~1 .88 times the average speed of continuous irrigation .And the second period's water propulsion length after watering was 1 .50~1 .71 times that of continuous irrigation .These proved that surge irrigation finished the irrigation task with high quality .At the same time ,the water use efficiency of winter wheat increased by 10 .41% .%试验利用山东引黄灌区内原有机井灌溉设施,在灌区生产较普遍规格(3m×95m)畦田内进行波涌流灌溉,并在水流推进、土壤含水率变化、冬小麦水分利用效率方面与连续灌溉进行了对比。试验条件下研究结果表明,周期数为2,节水率为10%的波涌流灌第二周期平均水流推进速度为连续灌溉的1.85~1.88倍,波涌流灌第二周期停水后的冲长为连续灌停水后的1.50~1.71倍,可以高质量完成灌溉任务,并且冬小麦水分利用效率提高10.41%。

  10. Human exposure risk to heavy metals through groundwater used for drinking in an intensively irrigated river delta

    Science.gov (United States)

    Vetrimurugan, E.; Brindha, K.; Elango, L.; Ndwandwe, Osman Muzi

    2016-09-01

    Drinking water containing heavy metals above the maximum permissible limits cause potential risk to human health. The aim of this study was to determine the groundwater suitability for drinking use based on heavy metal concentration and the associated human exposure risk in an intensively irrigated part of the Cauvery river basin, Tamil Nadu, India. Sixteen heavy metals analysed were in the order of dominance of chromium water quality, and silver, lead and nickel were above limits in all the groundwater samples. In less than 50 % of the groundwater samples, aluminium, boron, cadmium, copper, iron and manganese exceeded their individual permissible limits. Heavy metal pollution index based on 11 heavy metals indicated that groundwater quality of this area is poor-to-unsuitable. Non-carcinogenic risk for humans due to ingestion of groundwater through drinking water pathway was very high for infants, children and adults. Silver, lead, nickel, cadmium and manganese largely contributed to the health hazard. Sources of heavy metals were identified to be geological and from human activities, i.e., application of fertilizers in agricultural fields, seawater intrusion due to intensive pumping for agriculture and wastewater from industries. Groundwater and surface water in this area pose large threat due to high levels of heavy metals, and it is necessary to avoid this water for drinking due to potential risk of health hazard. This study also demonstrated the application of HPI and human exposure hazard index to study the groundwater quality based on heavy metals' concentration.

  11. Tracking solutes and water from subsurface drip irrigation application of coalbed methane–produced waters, Powder River Basin, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Engle, Mark A. [U.S. Geological Survey. Reston, VA (United States); Bern, Carleton R. [U.S. Geological Survey. Denver, CO (United States); Healy, Richard W. [U.S. Geological Survey. Denver, CO (United States); Sams, James I. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Zupancic, John W. [BeneTerra LLC. Sheridan, WY (United States); Schroeder, Karl T. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)

    2011-09-01

    One method to beneficially use water produced from coalbed methane (CBM) extraction is subsurface drip irrigation (SDI) of croplands. In SDI systems, treated CBM water (injectate) is supplied to the soil at depth, with the purpose of preventing the buildup of detrimental salts near the surface. The technology is expanding within the Powder River Basin, but little research has been published on its environmental impacts. This article reports on initial results from tracking water and solutes from the injected CBM-produced waters at an SDI system in Johnson County, Wyoming. In the first year of SDI operation, soil moisture significantly increased in the SDI areas, but well water levels increased only modestly, suggesting that most of the water added was stored in the vadose zone or lost to evapotranspiration. The injectate has lower concentrations of most inorganic constituents relative to ambient groundwater at the site but exhibits a high sodium adsorption ratio. Changes in groundwater chemistry during the same period of SDI operation were small; the increase in groundwater-specific conductance relative to pre-SDI conditions was observed in a single well. Conversely, groundwater samples collected beneath another SDI field showed decreased concentrations of several constituents since the SDI operation. Groundwater-specific conductance at the 12 other wells showed no significant changes. Major controls on and compositional variability of groundwater, surface water, and soil water chemistry are discussed in detail. Findings from this research provide an understanding of water and salt dynamics associated with SDI systems using CBM-produced water.

  12. Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

  13. Integrating MODFLOW and GIS technologies for assess-ing impacts of irrigation management and groundwater use in the Hetao Irrigation District, Yellow River basin

    Institute of Scientific and Technical Information of China (English)

    XU Xu; HUANG GuanHua; QU ZhongYi

    2009-01-01

    Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district.Application of water-saving practices (WSPs) is required for the sustainable agricultural development.The human activities including WSPs and increase of groundwater abstrac-tion can lower down the groundwater table, which is helpful to the salinity control.Meanwhile, an ex-cessively large groundwater table depth may result in negative impact on crop growth and fragile eco-logical environment.In this paper, the Jiefangzha irrigation system in Hetao irrigation district was se-lected as a typical area, a groundwater flow model based on Arclnfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area.The pre-and post-processing of model data was performed efficiently by using the available GIS tools.The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA).The model was calibrated and validated with in-dependent data sets.Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

  14. Assessment of the Environmental Impacts of Coalbed Methane Development in the Powder River Basin - Use of Coalbead Methane Produced Water for Cropland Irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Morris

    2009-01-30

    Water quality is a major concern with regard to development of coalbed methane (CBM) in the Powder River Basin, Wyoming. Large quantities of water are being produced and discharged as a by-product in the process of releasing natural gas from coal. Current practices of discharging large volumes of water into drainage channels or using it to irrigate cropland areas has the potential to elevate salinity and sodicity in soils. Elevated salinity affects the ability of plants to uptake water to facilitate biochemical processes such as photosynthesis and plant growth. Elevated sodicity in irrigation water adversely affects soil structure necessary for water infiltration, nutrient supply, and aeration. Salinity and sodicity concentrations are important in that a sodic soil can maintain its structure if the salinity level is maintained above the threshold electrolyte concentration. In this study, cropland soil and CBM water were treated with gypsum and sulfur. Changes in soil chemistry among different treatments were monitored using a split plot experiment. The CBM water used for irrigation had an EC of 1380 {micro}S cm{sup -1} and SAR of 24.3 mmol{sup 1/2} L{sup -1/2}. Baseline and post treatment soil samples were collected to a depth of 60 cm within each study plot, analyzed, and characterized for chemical parameters. Comparisons between Spring 2004 and Fall 2004 soil chemistry data after one irrigation season (using the equivalent of 1 month of irrigation water or {approx}12 inches) indicated that irrigating with Piney Creek water or a 50:50 blend of Piney Creek water and CBM water did not cause SAR values to increase. A combination of using a gypsum amendment to the soil along with a gypsum injection and sulfur burner treatment to the irrigation water resulted in the lowest SAR value in the first soil horizon among treatments irrigated solely with CBM produced water. The SAR value resulting from this combination treatment was 53% lower than using CBM water with no

  15. 76 FR 58249 - Notice of Availability of Proposed Low Effect Habitat Conservation Plan for Tumalo Irrigation...

    Science.gov (United States)

    2011-09-20

    ... Effect Habitat Conservation Plan for Tumalo Irrigation District's Tumalo Conservation Project AGENCY... Tumalo Irrigation District's (TID) application for an incidental take permit, pursuant to the Endangered... Columbia River Steelhead in the Deschutes River basin that may occur from irrigation activities...

  16. The Characteristics of Soil N Accumulation and Movement in Different Farmlands in the Yellow River Irrigation Region of Ningxia, China

    Directory of Open Access Journals (Sweden)

    KE Ying

    2014-02-01

    Full Text Available The greenhouse fields(n=4and open fields with rotation of paddy-upland crops(n=4were chosen in the Yellow River Irrigation Region of Ningxia. A method of multiple-points field sampling investigation and laboratory analysis was conducted to study the charac-teristics of soil N accumulation and distribution in different soil profiles and its movement effect on N content in the shallow groundwater from two different farmlands. The results indicated that total soluble N(TSN, NO3--N and soluble organic N(SONcontents in 0~150 cm soil in greenhouse fields were significantly higher than that in open fields, and the average contents in the former fields were 1.5~5.6, 1.5~3.4, 1.6~9.8 times as that in the latter fields, respectively. Different forms of N were mainly accumulated in 0~5 cm and 5~20 cm soil depth in green-house fields, and which were accumulated in 40~100 cm soil depth in open fields. Soil TSN accounted for TN by 5.4%~11.5% and 2.2%~4.9% in the greenhouse and open fields, respectively, and the former had a higher risk of soil N leaching losses. Different forms of dissolved N accumulation amount were SON>NO3--N>NH4+-N in 0~150 cm soil in greenhouse fields, and with the order of NO3--N>SON>NH4+-N in open fields. The TSN, NO3--N and SON contents in the shallow groundwater in greenhouse fields were also significantly higher than that in open fields, the former were 9.5, 13.8, 7.0 times as that in the latter, respectively. Therefore, both NO3--N and SON could be important soil N accumulation forms in these two different farmlands, and that may pollute the shallow groundwater in these two different fields.

  17. Tracking solutes and water from subsurface drip irrigation application of coalbed methane-produced waters, Powder River Basin, Wyoming

    Science.gov (United States)

    Engle, M.A.; Bern, C.R.; Healy, R.W.; Sams, J.I.; Zupancic, J.W.; Schroeder, K.T.

    2011-01-01

    One method to beneficially use water produced from coalbed methane (CBM) extraction is subsurface drip irrigation (SDI) of croplands. In SDI systems, treated CBMwater (injectate) is supplied to the soil at depth, with the purpose of preventing the buildup of detrimental salts near the surface. The technology is expanding within the Powder River Basin, but little research has been published on its environmental impacts. This article reports on initial results from tracking water and solutes from the injected CBM-produced waters at an SDI system in Johnson County, Wyoming. In the first year of SDI operation, soil moisture significantly increased in the SDI areas, but well water levels increased only modestly, suggesting that most of the water added was stored in the vadose zone or lost to evapotranspiration. The injectate has lower concentrations of most inorganic constituents relative to ambient groundwater at the site but exhibits a high sodium adsorption ratio. Changes in groundwater chemistry during the same period of SDI operation were small; the increase in groundwater-specific conductance relative to pre-SDI conditions was observed in a single well. Conversely, groundwater samples collected beneath another SDI field showed decreased concentrations of several constituents since the SDI operation.Groundwater-specific conductance at the 12 other wells showed no significant changes. Major controls on and compositional variability of groundwater, surface water, and soil water chemistry are discussed in detail. Findings from this research provide an understanding of water and salt dynamics associated with SDI systems using CBM-produced water. Copyright ??2011. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

  18. Field screening of water, soil, bottom sediment, and biota associated with irrigation drainage in the Dolores Project and the Macos River basin, southwestern Colorado, 1994

    Science.gov (United States)

    Butler, D.L.; Osmundson, B.C.; Krueger, R.P.

    1997-01-01

    A reconnaissance investigation for the National Irrigation Water Quality Program in 1990 indicated elevated selenium concentrations in some water and biota samples collected in the Dolores Project in southwestern Colorado. High selenium concentrations also were indicated in bird samples collected in the Mancos Project in 1989. In 1994, field screenings were done in parts of the Dolores Project and Mancos River Basin to collect additional selenium data associated with irrigation inthose areas. Selenium is mobilized from soils in newly irrigated areas of the Dolores Project called the Dove Creek area, which includes newly (since 1987) irrigated land north of Cortez and south of Dove Creek.Selenium was detected in 18 of 20stream samples, and the maximum concentration was 12micrograms per liter. The Dove Creek area is unique compared to other study areas of the National Irrigation Water Quality Program becauseselenium concentrations probably are indicative of initial leaching conditions in a newly irrigated area.Selenium concentrations in nine shallow soil samples from the Dove Creek area ranged from 0.13 to 0.20 micrograms per gram. Selenium concentrations in bottom sediment from six ponds were less than the level of concern for fish and wildlife of 4 micrograms per gram. Many biota samples collected in the Dove Creek area had elevated selenium concentrations when compared to various guidelines and effect levels,although selenium concentrations in water, soil, and bottom sediment were relatively low. Selenium concentrations in 12 of 14 aquatic-invertebratesamples from ponds exceeded 3 micrograms per gram dry weight, a dietary guideline for protection of fish and wildlife. The mean seleniumconcentration of 10.3 micrograms per gram dry weight in aquatic bird eggs exceeded the guideline for reduced hatchability of 8 micrograms per gramdry weight. Two ponds in the Dove Creek area had a high selenium hazard rating based on a new protocol for assessing selenium hazard in

  19. Improving potato cultivation using siphons for partial root-zone drying irrigation: A case study in the Blue Nile river basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    Yactayo Wendy

    2017-02-01

    Full Text Available Partial root-zone drying (PRD is an irrigation technique which consists of alternating the water supply from one furrow to another, and keeping the other one dry during the weekly alternation period. Studies assessing PRD in potato have reported a 30-50% of water savings with no tuber yield reductions and an increase of antioxidant concentrations and marketable tubers. In this study, we adapted the PRD technique to rural Ethiopian conditions and compared it against the customary (C irrigation practiced by local farmers. Two PRD alternatives were evaluated; with (PRDs and without (PRDw locally made flexible-hose siphons. Only PRDs showed no significant differences in total (35.8±1.6 t ha-1 and marketable (34.2±1.6 t ha-1 tuber yield when compared with customary irrigation (39.4±1.3 and 37.6±1.2 t ha-1 corresponding to total and marketable yield, respectively. The PRDw was more water restricted, showing significantly lower total (29.7±1.1 t ha-1 and marketable (27.6±1.2 t ha-1 yields. PRDs had the benefit of a better control of applied water allowing a saving of 50% of the irrigation water without negatively affecting yield. The use of the siphons PRD technique provides options for saving scarce water and reaching out to many smallholder farmers who are in serious need of irrigation water in the Blue Nile river basin.

  20. Perspective: Towards environmentally acceptable criteria for downstream fish passage through mini hydro and irrigation infrastructure in the Lower Mekong River Basin

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, Lee J.; Daniel Deng, Z.; Thorncraft, Garry; Boys, Craig A.; Brown, Richard S.; Singhanouvong, Douangkham; Phonekhampeng, Oudom

    2014-01-01

    Tropical rivers have high annual discharges optimal for hydropower and irrigation development. The Mekong River is one of the largest tropical river systems, supporting a unique mega-diverse fish community. Fish are an important commodity in the Mekong, contributing a large proportion of calcium, protein, and essential nutrients to the diet of the local people and providing a critical source of income for rural households. Many of these fish migrate not only upstream and downstream within main-channel habitats but also laterally into highly productive floodplain habitat to both feed and spawn. Most work to date has focused on providing for upstream fish passage, but downstream movement is an equally important process to protect. Expansion of hydropower and irrigation weirs can disrupt downstream migrations and it is important to ensure that passage through regulators or mini hydro systems is not harmful or fatal. Many new infrastructure projects (<6 m head) are proposed for the thousands of tributary streams throughout the Lower Mekong Basin and it is important that designs incorporate the best available science to protect downstream migrants. Recent advances in technology have provided new techniques which could be applied to Mekong fish species to obtain design criteria that can facilitate safe downstream passage. Obtaining and applying this knowledge to new infrastructure projects is essential in order to produce outcomes that are more favorable to local ecosystems and fisheries.

  1. Water Productivity Mapping (WPM) Using Landsat ETM+ Data for the Irrigated Croplands of the Syrdarya River Basin in Central Asia.

    Science.gov (United States)

    Platonov, Alexander; Thenkabail, Prasad S; Biradar, Chandrashekhar M; Cai, Xueliang; Gumma, Muralikrishna; Dheeravath, Venkateswarlu; Cohen, Yafit; Alchanatis, Victor; Goldshlager, Naftali; Ben-Dor, Eyal; Vithanage, Jagath; Manthrithilake, Herath; Kendjabaev, Shavkat; Isaev, Sabirjan

    2008-12-10

    The overarching goal of this paper was to espouse methods and protocols for water productivity mapping (WPM) using high spatial resolution Landsat remote sensing data. In a world where land and water for agriculture are becoming increasingly scarce, growing "more crop per drop" (increasing water productivity) becomes crucial for food security of future generations. The study used time-series Landsat ETM+ data to produce WPMs of irrigated crops, with emphasis on cotton in the Galaba study area in the Syrdarya river basin of Central Asia. The WPM methods and protocols using remote sensing data consisted of: (1) crop productivity (ton/ha) maps (CPMs) involvingcrop type classification, crop yield and biophysical modeling, and extrapolating yield models to larger areas using remotely sensed data; (2) crop water use (m³/ha) maps (WUMs) (or actual seasonal evapotranspiration or actual ET) developed through Simplified Surface Energy Balance (SSEB) model; and (3) water productivity (kg/m³) maps (WPMs) produced by dividing raster layers of CPMs by WUMs. The SSEB model calculated WUMs (actual ET) by multiplying the ET fractionby reference ET. The ETfraction was determined using Landsat thermal imagery by selecting the "hot" pixels (zero ET) and "cold" pixels (maximum ET). The grass reference ET was calculated by FAO Penman-Monteith method using meteorological data. The WPMs for the Galaba study area demonstrated a wide variations (0-0.54 kg/m³) in water productivity of cotton fields with overwhelming proportion (87%) of the area having WP less than 0.30 kg/m³, 11% of the area having WP in range of 0.30-0.36 kg/m³, and only 2% of the area with WP greater than 0.36 kg/m³. These results clearly imply that there are opportunities for significant WP increases in overwhelming proportion of the existing croplands. The areas of low WP are spatially pin-pointed and can be used as focus for WP improvements through better land and water management practices.

  2. Water Productivity Mapping (WPM Using Landsat ETM+ Data for the Irrigated Croplands of the Syrdarya River Basin in Central Asia

    Directory of Open Access Journals (Sweden)

    Sabirjan Isaev

    2008-12-01

    Full Text Available The overarching goal of this paper was to espouse methods and protocols for water productivity mapping (WPM using high spatial resolution Landsat remote sensing data. In a world where land and water for agriculture are becoming increasingly scarce, growing “more crop per drop” (increasing water productivity becomes crucial for food security of future generations. The study used time-series Landsat ETM+ data to produce WPMs of irrigated crops, with emphasis on cotton in the Galaba study area in the Syrdarya river basin of Central Asia. The WPM methods and protocols using remote sensing data consisted of: (1 crop productivity (ton/ha maps (CPMs involvingcrop type classification, crop yield and biophysical modeling, and extrapolating yield models to larger areas using remotely sensed data; (2 crop water use (m3/ha maps (WUMs (or actual seasonal evapotranspiration or actual ET developed through Simplified Surface Energy Balance (SSEB model; and (3 water productivity (kg/m3 maps (WPMs produced by dividing raster layers of CPMs by WUMs. The SSEB model calculated WUMs (actual ET by multiplying the ET fractionby reference ET. The ETfraction was determined using Landsat thermal imagery by selecting the “hot” pixels (zero ET and “cold” pixels (maximum ET. The grass reference ET was calculated by FAO Penman-Monteith method using meteorological data. The WPMs for the Galaba study area demonstrated a wide variations (0-0.54 kg/m3 in water productivity of cotton fields with overwhelming proportion (87% of the area having WP less than 0.30 kg/m3, 11% of the area having WP in range of 0.30-0.36 kg/m3, and only 2% of the area with WP greater than 0.36 kg/m3. These results clearly imply that there are opportunities for significant WP increases in overwhelming proportion of the existing croplands. The areas of low WP are spatially pin-pointed and can be used as focus for WP improvements

  3. Sun Allergy

    Science.gov (United States)

    ... if you have unusual, bothersome skin reactions after exposure to sunlight. For severe or persistent symptoms, you may need ... m. when the sun is brightest. Avoid sudden exposure to lots of sunlight. Many people have sun allergy symptoms when they ...

  4. 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.

  5. 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

  6. 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.

  7. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the middle Green River basin, Utah, 1986-87

    Science.gov (United States)

    Stephens, D.W.; Waddell, Bruce; Miller, J.B.

    1988-01-01

    Reconnaissance of wildlife areas in the middle Green River basin of Utah was conducted during 1986 and 1987 to determine whether irrigation drainage has caused, or has the potential to cause significant harmful effects on human health, fish, and wildlife, or may adversely affect the suitability of water for beneficial uses. Studies at Stewart Lake Waterfowl Management Area and Ouray National Wildlife Refuge indicated that concentrations of boron, selenium, and zinc in water, bottom sediment, and biological tissue were sufficiently large to be harmful to fish and wildlife, and to adversely affect beneficial uses of water. Selenium is the principal element of concern in both areas. Concentrations of dissolved selenium in irrigation drain water entering Stewart Lake Waterfowl Management Area ranged from 14-140 micrograms/L (ug/L) and consistently exceeded Utah standards for wildlife protection in water in two of the four drains. Concentrations of boron and zinc exceeded Utah standards only occasionally in the drain waters. Concentrations of total selenium in sediments collected where the drains discharge into the lake were 10-85 ug/gm. Liver tissue collected from American coots at Stewart Lake Waterfowl Management Area contained concentrations of selenium from 4.9-26 ug/gm (dry weight), and whole body samples of carp contained as much as 31 ug/gm (dry weight). Concentrations of selenium in Potamogeton and blue-green algae ranged from 2.1-27 ug/gm. Concentrations of boron, selenium, and zinc were also measured in water from Ouray National Wildlife Refuge. Liver tissue of American coots from the North Roadside Pond, which receives irrigation tailwater, contained a geometric-mean concentration of selenium of 32 ug/gm (dry weight). Five water-bird eggs collected from the North and South Roadside Ponds contained selenium concentrations of 63-120 ug/gm (dry weight). (Lantz-PTT)

  8. Influence of approach velocity and mesh size on the entrainment and contact of a lowland river fish assemblage at a screened irrigation pump.

    Directory of Open Access Journals (Sweden)

    Craig A Boys

    Full Text Available Fish screens can help prevent the entrainment or injury of fish at irrigation diversions, but only when designed appropriately. Design criteria cannot simply be transferred between sites or pump systems and need to be developed using an evidence-based approach with the needs of local species in mind. Laboratory testing is typically used to quantify fish responses at intake screens, but often limits the number of species that can studied and creates artificial conditions not directly applicable to screens in the wild. In this study a field-based approach was used to assess the appropriateness of different screen design attributes for the protection of a lowland river fish assemblage at an experimental irrigation pump. Direct netting of entrained fish was used along with sonar technology to quantify the probability of screen contact for a Murray-Darling Basin (Australia fish species. Two approach velocities (0.1 and 0.5 m.sec(-1 and different sizes of woven mesh (5, 10 and 20 mm were evaluated. Smaller fish (<150 mm in the assemblage were significantly more susceptible to entrainment and screen contact, especially at higher approach velocities. Mesh size appeared to have little impact on screen contact and entrainment, suggesting that approach velocity rather than mesh size is likely to be the primary consideration when developing screens. Until the effects of screen contacts on injury and survival of these species are better understood, it is recommended that approach velocities not exceed 0.1 m.sec(-1 when the desire is to protect the largest range of species and size classes for lowland river fish assemblages in the Murray-Darling Basin. The field method tested proved to be a useful approach that could compliment laboratory studies to refine fish screen design and facilitate field validation.

  9. Evaluation of groundwater suitability for domestic, irrigational, and industrial purposes: a case study from Thirumanimuttar river basin, Tamilnadu, India.

    Science.gov (United States)

    Vasanthavigar, M; Srinivasamoorthy, K; Prasanna, M V

    2012-01-01

    The Thirumanimuttar sub-basin forms an important groundwater province in south India, facing serious deficiency in both quality and quantity of groundwater due to increased demand associated with rapid population explosion, agricultural growth and industrial activities. A total of 194 groundwater samples were collected and 15 water quality parameters were analyzed using standard procedures. Na( + ), Cl( - ), Ca(2 + ), HCO(-)(3), Mg(2 + ) and SO(2-)(4) concentration ions are more dominant in both seasons. The total dissolved solids and electrical conductivity was observed good correlation with Na( + ), Cl( - ), HCO(-)(3), Ca(2 + ), Mg(2 + ), Cl( - ), PO(3-)(4) and NO(-)(3) ions indicating dominance of plagioclase feldspar weathering, anthropogenic input and over drafting of groundwater irrespective of seasons. The Hill-Piper diagram indicates alkaline earths exceed the alkalis, an increase of weak acids was noted during both the seasons. For assessing the groundwater for irrigation suitability parameters like total hardness, sodium adsorption ratio, residual sodium carbonate (RSC), permeability index, and sodium percentage are also calculated. Permanent hardness was noted in higher during both the seasons due to discharge of untreated effluents and ion exchange process. The RSC indicates 56% of the samples are not suitable for irrigation purposes in both seasons, if continuously used will affect the crop yield. From the results, nearly 72% of the samples are not suitable for irrigation.

  10. 水量平衡原理在测算南方河网灌区灌溉水利用系数中的应用%Application of Water Balance Principle in Irrigation Water Utilization Coefficient Calculation of South River Irrigation District

    Institute of Scientific and Technical Information of China (English)

    赵鹏涛; 陈春兰

    2015-01-01

    Irrigation water utilization coefficient is an important index to reflect the agricultural water use efficiency .In this paper , according to the actual situation of south River irrigation area ,the water balance principle is proposed to analyze the water use coeffi‐cient calculation method for south irrigation area .The detailed process is using the statistics data of existing water conservancy facili‐ties and pond to calculate the water use coefficient of the irrigation canal system on the basis of the determination of crop irrigation quota ,and then determining the irrigation water use coefficient .The result can be used as a reference or verification for water coeffi‐cient calculation of south river irrigation area .%灌溉水利用系数是反映农业用水效率的重要指标。根据南方河网灌区的实际,提出应用水量平衡原理,分析确定南方灌区的灌溉水利用系数的方法。是通过采用灌区已建水利工程和塘坝等水利设施供水统计资料,在确定作物灌溉定额的基础上,反推得出灌区的渠系水利用系数,最后分析确定灌区灌溉水利用系数,为南方灌区灌溉水利用系数测算分析提供借鉴或验证。

  11. Application of near-surface geophysics as part of a hydrologic study of a subsurface drip irrigation system along the Powder River floodplain near Arvada, Wyoming

    Science.gov (United States)

    Sams, James I.; Veloski, Garret; Smith, Bruce D.; Minsley, Burke J.; Engle, Mark A.; Lipinski, Brian A.; Hammack, Richard W.; Zupancic, John W.

    2014-01-01

    Rapid development of coalbed natural gas (CBNG) production in the Powder River Basin (PRB) of Wyoming has occurred since 1997. National attention related to CBNG development has focused on produced water management, which is the single largest cost for on-shore domestic producers. Low-cost treatment technologies allow operators to reduce their disposal costs, provide treated water for beneficial use, and stimulate oil and gas production by small operators. Subsurface drip irrigation (SDI) systems are one potential treatment option that allows for increased CBNG production by providing a beneficial use for the produced water in farmland irrigation.Water management practices in the development of CBNG in Wyoming have been aided by integrated geophysical, geochemical, and hydrologic studies of both the disposal and utilization of water. The U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) and the U.S. Geological Survey (USGS) have utilized multi-frequency airborne, ground, and borehole electromagnetic (EM) and ground resistivity methods to characterize the near-surface hydrogeology in areas of produced water disposal. These surveys provide near-surface EM data that can be compared with results of previous surveys to monitor changes in soils and local hydrology over time as the produced water is discharged through SDI.The focus of this investigation is the Headgate Draw SDI site, situated adjacent to the Powder River near the confluence of a major tributary, Crazy Woman Creek, in Johnson County, Wyoming. The SDI system was installed during the summer of 2008 and began operation in October of 2008. Ground, borehole, and helicopter electromagnetic (HEM) conductivity surveys were conducted at the site prior to the installation of the SDI system. After the installation of the subsurface drip irrigation system, ground EM surveys have been performed quarterly (weather permitting). The geophysical surveys map the heterogeneity of the near

  12. Aztec Suns

    Science.gov (United States)

    Petersen, Hugh

    2010-01-01

    The Aztec Sun Stone is a revered Mexican artifact. It is said to be perhaps the most famous symbol of Mexico, besides its flag. It primarily depicts the four great disasters that led to the migration of the Mexica people to modern-day Mexico City. The Aztec Sun Stone also contains pictographs depicting the way the Mexica measured time, and was…

  13. Aztec Suns

    Science.gov (United States)

    Petersen, Hugh

    2010-01-01

    The Aztec Sun Stone is a revered Mexican artifact. It is said to be perhaps the most famous symbol of Mexico, besides its flag. It primarily depicts the four great disasters that led to the migration of the Mexica people to modern-day Mexico City. The Aztec Sun Stone also contains pictographs depicting the way the Mexica measured time, and was…

  14. 渭干河平原绿洲灌区合理灌排比探讨%Rational Ratio of Irrigation to Drainage in Weigan River Irrigat ion District

    Institute of Scientific and Technical Information of China (English)

    胡顺军; 艾尼瓦尔·吾买尔; 田长彦; 周宏飞; 宋郁东; 王永平; 蒋庆华; 艾则孜; 黄文山; 吐尔逊

    2001-01-01

    根据灌区盐量平衡原理,采用实际监测资料,对渭干河及其所属的库车、沙雅、新和县平原绿洲灌区进行盐均衡分析,深入探讨了临界灌排比的影响因素及其确定方法。研究结果表明:(1)灌排比的概念简捷明了,体现了干旱区水利建设、灌溉农业的特点,可作为衡量干旱区绿洲灌区水盐运动状况的一个指标,同时亦是进行灌排管理、规划设计的科学依据。(2)临界灌排比与灌溉引水量、排水量、河水含盐浓度、排水含盐浓度等因素有关。渭干河、库车、沙雅、新和灌区临界灌排比分别为10.80,6.55,20.09,21.48。若没有特殊的地形地貌,干旱区绿洲灌区临界灌排比为21左右。(3)在干旱区进行水量平衡计算,制定灌溉制度以及进行灌溉排水管理时,应保证有一定量的深层渗漏,便于淋洗盐分,同时应完善排水系统,使灌区在小于临界灌排比下运行。%Based on the principle of salt equilibrium in irrigationdistricts, the salt e qu ilibrium of Weigan river irrigation district is analyzed by using measured data. The factors of affecting critical ratio of irrigation to drainage and the metho d of determining critical ratio of irrigation to drainage are also discussed pro foundly. The results show that: (1) The conception of the ratio of irrigation to drainage is brief, embodies the characteristics of water conservation construct ion and irrigation agriculture, which can be used as the criterion of estimating the dynamics of moisture-salt movement in plain oasis irrigation distract in arid area,and can also used as the scientific basis of management of irrigatio n and drainage ,planning and designing.(2)Critical ratio of irrigation to drainage is related to the irrigation water volume, drainage water volume ,salt content of irrigation water and drainage water and so on. The critical ratio of irrigati o n to drainage for Weigan

  15. Effect of Agricultural Practices on Hydrology and Water Chemistry in a Small Irrigated Catchment, Yakima River Basin, Washington

    Science.gov (United States)

    McCarthy, Kathleen A.; Johnson, Henry M.

    2009-01-01

    The role of irrigation and artificial drainage in the hydrologic cycle and the transport of solutes in a small agricultural catchment in central Washington's Yakima Valley were explored using hydrologic, chemical, isotopic, age-dating, and mineralogical data from several environmental compartments, including stream water, ground water, overland flow, and streambed pore water. A conceptual understanding of catchment hydrology and solute transport was developed and an inverse end-member mixing analysis was used to further explore the effects of agriculture in this small catchment. The median concentrations of major solutes and nitrates were similar for the single field site and for the catchment outflow site, indicating that the net effects of transport processes for these constituents were similar at both scales. However, concentrations of nutrients were different at the two sites, suggesting that field-scale variations in agricultural practices as well as nearstream and instream biochemical processes are important components of agricultural chemical transformation and transport in this catchment. This work indicates that irrigation coupled with artificial drainage networks may exacerbate the ecological effects of agricultural runoff by increasing direct connectivity between fields and streams and minimizing potentially mitigating effects (denitrification and dilution, for example) of longer subsurface pathways.

  16. Pollution of River Mahaweli and farmlands under irrigation by cadmium from agricultural inputs leading to a chronic renal failure epidemic among farmers in NCP, Sri Lanka.

    Science.gov (United States)

    Bandara, J M R S; Wijewardena, H V P; Bandara, Y M A Y; Jayasooriya, R G P T; Rajapaksha, H

    2011-10-01

    Chronic renal failure (CRF) associated with elevated dietary cadmium (Cd) among farming communities in the irrigated agricultural area under the River Mahaweli diversion scheme has reached a significantly higher level of 9,000 patients. Cadmium, derived from contaminated phosphate fertilizer, in irrigation water finds its way into reservoirs, and finally to food, causing chronic renal failure among consumers. Water samples of River Mahaweli and its tributaries in the upper catchment were analyzed to assess the total cadmium contamination of river water and the possible source of cadmium. Except a single tributary (Ulapane Stream, 3.9 μg Cd/l), all other tested tributaries carried more than 5 μg Cd/l, the maximum concentration level accepted to be safe in drinking water. Seven medium-sized streams carrying surface runoff from tea estates had 5.1-10 μg Cd/l. Twenty larger tributaries (Oya), where the catchment is under vegetable and home garden cultivation, carried 10.1-15 μg Cd/l. Nine other major tributaries had extremely high levels of Cd, reaching 20 μg Cd/l. Using geographic information system (GIS), the area in the catchment of each tributary was studied. The specific cropping system in each watershed was determined. The total cadmium loading from each crop area was estimated using the rates and types of phosphate fertilizer used by the respective farmers and the amount of cadmium contained in each type of fertilizer used. Eppawala rock phosphate (ERP), which is mostly used in tea estates, caused least pollution. The amount of cadmium in tributaries had a significant positive correlation with the cadmium loading of the cropping system. Dimbula Tea Estate Stream had the lowest Cd loading (495.9 g/ha/year), compared with vegetable-growing areas in Uma Oya catchment with 50,852.5 g Cd/ha/year. Kendall's τ rank correlation value of total Cd loading from the catchment by phosphate fertilizer used in all crops in the catchment to the Cd content in

  17. Observations on the quality of desalinated water in the Segura river basin. Irrigation and supply; Observaciones sobre la calidad del agua desalada en la Cuenca del Seguro. Riego y abastecimiento

    Energy Technology Data Exchange (ETDEWEB)

    Latorre Carrion, M.; Camara Zapata, J. M.

    2004-07-01

    Desalination of seawater by reverse osmosis (RO) is an unconventional water resource that could help to maintain irrigation crops in the Segura river basin. Its suitability for irrigation purposes needs to be studied to prevent the soil from being harmed and the quality and yield of the crops from falling. This article describes a simulation of the functioning of a RO desalination plant based on actual seawater data (Mazarron). The results show that desalinated water has an ionic balance giving rise to a high specific absorption rate of Na+ and low electrical conductivity, which means that its quality for agricultural purposes is deficient. The article sets out the requirements for irrigation water and the problems they pose for desalination plants. The suitability of desalinated water for agricultural purposes is ecaminaed, corrective measures proposed and the cost involved quantified. (Author) 5 refs.

  18. Determining Regional Actual Evapotranspiration of Irrigated Crops and Natural Vegetation in the São Francisco River Basin (Brazil Using Remote Sensing and Penman-Monteith Equation

    Directory of Open Access Journals (Sweden)

    Antônio H. de C. Teixeira

    2010-05-01

    Full Text Available To achieve sustainable development and to ensure water availability in hydrological basins, water managers need tools to determine the actual evapotranspiration (ET on a large scale. Field energy balances from irrigated and natural ecosystems together with a net of agro-meteorological stations were used to develop two models for ET quantification at basin scale, based on the Penman-Monteith equation. The first model (PM1 uses the resistances to the latent heat fluxes estimated from satellite measurements, while the second one (PM2 is based on the ratio of ET to the reference evapotranspiration (ET0 and its relation to remote sensing parameters. The models were applied in the Low-Middle São Francisco river basin in Brazil and, after comparison against field results, showed good agreements with PM1 and PM2 explaining, respectively, 79% and 89% of the variances and mean square errors (RMSE of 0.44 and 0.34 mm d−1. Even though the PM1 model was not chosen for ET calculations, the equation for surface resistance (rs was applied to infer the soil moisture conditions in a simplified vegetation classification. The maximum values of rs were for natural vegetation—caatinga (average of 1,937 s m−1. Wine grape and mango orchard presented similar values around 130 s m−1, while table grape presented the lowest ones, averaging 74 s m−1. Petrolina and Juazeiro, in Pernambuco (PE and Bahia (BA states, respectively, were highlighted with the biggest irrigated areas. The highest increments are for vineyards and mango orchards. For the first crop the maximum increment was verified between 2003 and 2004 in Petrolina-PE, when the cultivated area increased 151%. In the case of mango orchards the most significant period was from 2005 to 2006 in Juazeiro-BA (129%. As the best performance was for PM2, it was selected and used to analyse the regional ET at daily and annual scales, making use of Landsat images and a geographic information system for different

  19. Estimating spatiotemporal variability and sustainability of shallow groundwater in a well-irrigated plain of the Haihe River basin using SWAT model

    Science.gov (United States)

    Zhang, Xueliang; Ren, Li; Kong, Xiangbin

    2016-10-01

    Quantitatively estimating the spatiotemporal variability and sustainability of shallow groundwater with a distributed hydrological model could provide an important basis for proper groundwater management, especially in well-irrigated areas. In this study, the Soil and Water Assessment Tool (SWAT) model was modified and applied to a well-irrigated plain of the Haihe River basin. First, appropriate initial values of the parameters in the groundwater module were determined based on abundant hydrogeological investigations and assessment. Then, the model was satisfactorily calibrated and validated using shallow groundwater table data from 16 national wells monitored monthly from 1993 to 2010 and 148 wells investigated yearly from 2006 to 2012. To further demonstrate the model's rationality, the multi-objective validation was conducted by comparing the simulated groundwater balance components, actual evapotranspiration, and crop yields to multiple sources data. Finally, the established SWAT was used to estimate both shallow groundwater table fluctuation and shallow aquifer water storage change in time and space. Results showed that the average shallow groundwater table declined at a rate of 0.69-1.56 m a-1, which depleted almost 350 × 108 m3 of shallow aquifer water storage in the cropland during the period of 1993-2012. Because of the heterogeneity of the underlying surface and precipitation, these variations were spatiotemporally different. Generally, the shallow groundwater table declined 1.43-1.88 m during the winter wheat (Triticum aestivum L.) growing season, while it recovered 0.28-0.57 m during the summer maize (Zea mays L.) growing season except when precipitation was exceptionally scarce. According to the simulated depletion rate, the shallow aquifer in the study area may face a depletion crisis within the next 80 years. This study identified the regions where prohibitions or restrictions on shallow groundwater exploitation should be urgently carried out.

  20. Controls on selenium distribution and mobilization in an irrigated shallow groundwater system underlain by Mancos Shale, Uncompahgre River Basin, Colorado, USA

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Taylor J.; Mast, M. Alisa; Thomas, Judith; Keith, Gabrielle

    2016-10-01

    Elevated selenium (Se) concentrations in surface water and groundwater have become a concern in areas of the Western United States due to the deleterious effects of Se on aquatic ecosystems. Elevated Se concentrations are most prevalent in irrigated alluvial valleys underlain by Se-bearing marine shales where Se can be leached from geologic materials into the shallow groundwater and surface water systems. This study presents groundwater chemistry and solid-phase geochemical data from the Uncompahgre River Basin in Western Colorado, an irrigated alluvial landscape underlain by Se-rich Cretaceous marine shale. We analyzed Se species, major and trace elements, and stable nitrogen and oxygen isotopes of nitrate in groundwater and aquifer sediments to examine processes governing selenium release and transport in the shallow groundwater system. Groundwater Se concentrations ranged from below detection limit (< 0.5 μg L{sup −1}) to 4070 μg L{sup −1}, and primarily are controlled by high groundwater nitrate concentrations that maintain oxidizing conditions in the aquifer despite low dissolved oxygen concentrations. High nitrate concentrations in non-irrigated soils and nitrate isotopes indicate nitrate is largely derived from natural sources in the Mancos Shale and alluvial material. Thus, in contrast to areas that receive substantial NO{sub 3} inputs through inorganic fertilizer application, Se mitigation efforts that involve limiting NO{sub 3} application might have little impact on groundwater Se concentrations in the study area. Soluble salts are the primary source of Se to the groundwater system in the study area at-present, but they constitute a small percentage of the total Se content of core material. Sequential extraction results indicate insoluble Se is likely composed of reduced Se in recalcitrant organic matter or discrete selenide phases. Oxidation of reduced Se species that constitute the majority of the Se pool in the study area could be a potential

  1. Sustainable use of land and water under rainfed and deficit irrigation conditions in Ogun-Osun River Basin, Nigeria

    NARCIS (Netherlands)

    Adeboye, O.B.

    2015-01-01

    Summary

    Human population is increasing faster than ever in the history. There is an urgent need to scale up food production in order to meet up with food demands, especially in Sub-Saharan Africa. In Ogun-Osun River Basin, Nigeria, more than 95% of the crop production is

  2. Sustainable use of land and water under rainfed and deficit irrigation conditions in Ogun-Osun River Basin, Nigeria

    NARCIS (Netherlands)

    Adeboye, O.B.

    2015-01-01

    Summary

    Human population is increasing faster than ever in the history. There is an urgent need to scale up food production in order to meet up with food demands, especially in Sub-Saharan Africa. In Ogun-Osun River Basin, Nigeria, more than 95% of the crop production is do

  3. Sustainable use of land and water under rainfed and deficit irrigation conditions in Ogun-Osun River Basin, Nigeria

    NARCIS (Netherlands)

    Adeboye, O.B.

    2015-01-01

    Summary

    Human population is increasing faster than ever in the history. There is an urgent need to scale up food production in order to meet up with food demands, especially in Sub-Saharan Africa. In Ogun-Osun River Basin, Nigeria, more than 95% of the crop production is do

  4. Sun meter

    Science.gov (United States)

    Younskevicius, Robert E.

    1978-01-01

    A simple, inexpensive device for measuring the radiation energy of the sun impinging on the device. The measurement of the energy over an extended period of time is accomplished without moving parts or tracking mechanisms.

  5. The Sun

    CERN Document Server

    Golub, Leon

    2017-01-01

    Essential for life on earth and a major influence on our environment, the Sun is also the most fascinating object in the daytime sky. Every day we feel the effect of its coming and going – literally the difference between day and night. But figuring out what the Sun is, what it’s made of, why it glows so brightly, how old it is, how long it will last – all of these take thought and observation. Leon Golub and Jay M. Pasachoff offer an engaging and informative account of what scientists know about the Sun, and the history of these discoveries. Solar astronomers have studied the Sun over the centuries both for its intrinsic interest and in order to use it as a laboratory to reveal the secrets of other stars. The authors discuss the surface of the Sun, including sunspots and their eleven-year cycle, as well as the magnetism that causes them; the Sun’s insides, as studied mainly from seismic waves that astronomers record on its surface; the outer layers of the Sun that we see from Earth only at eclipses ...

  6. Midnight sun

    Energy Technology Data Exchange (ETDEWEB)

    Brunger, A.P.; Lambert, S.B.; Gagnon, M.P.

    1990-09-01

    Midnight Sun, the University of Waterloo's solar-electric car, was designed and built by about 30 engineering, kinesiology and physics students for the GM Sunrayce USA held in July 1990. The car measures 2 m by 4.2 m, weighs 224 kg, can collect about 1000 W of solar electricity in full sun, and had a top speed of 79 km/h. The race took 11 days to cover the 1644 miles from the Epcot Center in Lake Buena Vista, Florida to the GM Technical Center in Warren, Michigan. Thirty-two cars, powered only by solar energy, competed in this race. Midnight Sun showed its potential during the race qualifying runs by completing the required qualifying course with the 12th fastest time of 52.83 seconds, and the 6th fastest trap speed of 63 km/h. During the Sunrayce, Midnight Sun came in second on day 1 of the race, tenth on day 6, and eighth on day 7, and was one of only 17 solar cars that were able to make it up the toughest hill in the race on day 8. The most serious problems encountered by the car were a weak rear suspension, power losses, and failure of bypass diodes in the photovoltaic array. Midnight Sun was in 17th place overall at the end of day 9. At about 11:00 am on day 10 in Ohio, the Waterloo car was moving at 60 km/h when it was bumped off the road by an out of control pickup truck. The solar car driver was not hurt. Despite the difficulties, the next day Midnight Sun was repaired and driven across the finish line at the ceremonial finish. After receiving time penalties for not completing the last day and a half of the race, Midnight Sun was awarded 24th place with an official cumulative time of 114 h 37 min 15 s. 4 figs., 4 tabs.

  7. 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.

  8. Potential health hazards of the water resources development: a health survey in the Phitsanulok Irrigation Project, Nan River Basin, Northern Thailand.

    Science.gov (United States)

    Bunnag, T; Sornmani, S; Impand, P; Harinasuta, C

    1980-12-01

    A health survey was carried out among residents of 33 villages under the Phitsanulok Irrigation Project Area, Nan River Basin, Northern Thailand, whereby general health conditions were examined including intradermal tests for schistosomiasis japonica, stools for intestinal parasites and sera tested by circumoval precipitin test for antibodies to S. japonicum and by agglutination test for leptospiral infection. Health investigations revealed that 913 (60.9%) of 1,499 people examined had experienced gastro-intestinal disorders, 254 (17%) had poor oral hygiene and a few had mild anemia. 799 (62%) of 1,298 examined had intestinal parasites. Hookworm (45%) was most common, followed by Opisthorchis viverrini (20%), Entamoeba coli (10%), Ascaris lumbricoides (6%), intestinal flukes (2%), Enterobius vermicularis (1%) and Giardia lamblia (1%). 149 (10%) of 1,422 people gave positive skin reaction to crude S. japonicum antigen. Circumoval precipitin test was strongly positive in 7 (1.6%) persons out of 449 tested for schistosome infection and 6 (4.0%) out of 1,358 people were positive for leptospiral infection. The significant endemic diseases as potential health problems in this water resources development are discussed.

  9. Agricultural Irrigation Water Use in a Closed Basin  and the Impacts on Water Productivity: The Case of  the Guadalquivir River Basin (Southern Spain

    Directory of Open Access Journals (Sweden)

    Alfonso Expósito

    2017-02-01

    Full Text Available This paper analyses the agricultural irrigation water use in a closed basin and the impacts on water productivity, and examines how they have affected the ‘closure’ process of the Guadalquivir river basin observed in recent decades. Following a period of expansion in irrigation, an administrative moratorium was declared on new irrigated areas in 2005. Since then, the main policy measure has been aimed at the modernisation of irrigated agriculture and the implementation of water conservation technologies. The analysis carried out in this paper shows a significant increase in mean irrigation water productivity in the pre‐moratorium period (1989–2005, driven by the creation of new irrigated areas devoted to high value crops and with a dominant use of deficit irrigation strategies, while a second phase (2005–2012 is characterised by slower growth in terms of the mean productivity of irrigation water, primarily as a result of a significant reduction in water use per area. Findings show that productivity gains seem to have reached a ceiling in this river basin, since technological innovations (such as new crops, deficit irrigation, and water‐saving and conservation technologies have reached the limits of their capacity to create new value.

  10. Little Sun

    DEFF Research Database (Denmark)

    Ebbesen, Toke Riis

    2017-01-01

    the ideas of Alfred Gell’s anthropology of art and the indicative framework derived from Argentinian semiotician Juan Pablo Bonta and Jørn Guldberg. The toy-like solar lamp Little Sun by Olafur Eliasson and Frederik Ottesen is used as case that blends the registers of social design and art......, and as an example of how designers attempt to determine meaning potentials through design in a complex interplay of different strategies. In the final analysis, what characterise objects like Little Sun is seldom that they communicate their meanings in themselves, but instead rely on forceful mediations to gain...

  11. Little sun

    DEFF Research Database (Denmark)

    Ebbesen, Toke Riis

    2017-01-01

    the ideas of Alfred Gell’s anthropology of art and the indicative framework derived from Argentinian semiotician Juan Pablo Bonta and Jørn Guldberg. The toy-like solar lamp Little Sun by Olafur Eliasson and Frederik Ottesen is used as case that blends the registers of social design and art......, and as an example of how designers attempt to determine meaning potentials through design in a complex interplay of different strategies. In the final analysis, what characterise objects like Little Sun is seldom that they communicate their meanings in themselves, but instead rely on forceful mediations to gain...

  12. 宁夏引黄灌区农业水价改革现状分析及思考%Analysis and Thoughts to Currently Agricultural Water Price Reform in Ningxia Yellow River Irrigation

    Institute of Scientific and Technical Information of China (English)

    刘思妤; 倪红珍; 张春玲; 陈根发

    2016-01-01

    In recent years,according to the requirements of the Ministry of water resources and the construction of water saving soci-ety in Ningxia Hui Autonomous Region,the irrigation area of Ningxia has achieved certain results by fully implementation of the ag-ricultural water price reform.In combination with the practical situation of irrigation area,this paper introduces in detail the irriga-tion water price reform,irrigation water supply cost and management income situation,analyzed the main problems existing in water price reform,put forward and set up scientific points irrigation,crop ladder water price standard and perfect the relevant supporting policies,organization and management,the concrete Suggestions of infrastructure construction,so as to provide reference for further implementing the reform of water price in Ningxia Yellow River irrigation.%近年来,按照国家水利部和宁夏回族自治区建设节水型社会的要求,宁夏引黄灌区全面推行了农业水价改革,取得了一定成效。结合灌区实际情况,详细介绍了灌区水价改革、灌区供水成本及管理处收益现状,分析水价改革中存在的主要问题,并提出建立分灌区、分作物的阶梯水价标准及完善相关配套政策、组织管理、基础建设的具体建议,旨在为宁夏引黄灌区进一步落实水价改革提供参考依据。

  13. Sun Proof

    Centers for Disease Control (CDC) Podcasts

    2012-10-23

    In this podcast for kids, the Kidtastics talk about the harmful effects of the sun and how to protect yourself from it.  Created: 10/23/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 10/23/2012.

  14. Simulation of Brackish Water Irrigation Management for Winter Wheat in the Yellow River Delta%黄河三角洲地区冬小麦微咸水灌溉制度模拟

    Institute of Scientific and Technical Information of China (English)

    庞桂斌; 徐征和; 刘培成; 郝爱鑫

    2016-01-01

    The rational development of shallow underground brackish water for agricultural irrigation,not only can solve the problem of water shortage,but also can descend underground water level to reduce the soil secondary salinization hazards,meanwhile,soil and water environment for crop growth will be improved. This paper selected the Yellow River delta as the study area,where freshwater is in short supply,groundwater is shallow and the soil water and salt movement is active. In order to investigate the most applicable irrigation schedule with slight saline water (2-5 g/L ) for winter wheat in the Yellow River delta,the validated finite element subsurface FLOW system (FEFLOW)model was used to evaluate the effect of various irrigation schedule on water and salt balance in soil,crop growth and groundwater table. The simulated results indicate that the optimal irrigation schedule of winter wheat is a)key time of irrigation is needed with enough slight saline water;b)two times of irrigation are needed with slight saline water mixed with fresh water and;c)three or four times of irrigation are needed with alternate of slight saline water and freshwater.%合理开发浅埋区地下微咸水用于灌溉不仅可以解决水资源短缺的问题,而且可以通过降低地下水位减轻土壤次生盐碱化,改善作物生长的水土环境。选择淡水资源紧缺、地下水埋深浅、土壤水盐运动剧烈的黄河三角洲地区,基于FEFLOW软件建立了引黄灌区的水流与溶质运移数值模拟模型,并应用率定和验证后的模型对多种微咸水(矿化度为2~5 g/L)灌溉方案进行模拟,综合考虑地下水位临界深度和冬小麦生育期耐盐极限,确立了较优的微咸水灌溉制度,包括一次性灌足关键微咸水、微咸水与淡水混合灌溉、微咸水与淡水轮流灌溉三种灌溉方式。

  15. Sustainable irrigation Agriculture in the Tarim River Basin of Western Xinjiang Province--A proposal for the extablishment of a Salinity Laboratory of P. R. China%中国新疆塔里木河流域的可持续灌溉农业--关于建立中国国家盐渍化研究实验室的建议

    Institute of Scientific and Technical Information of China (English)

    约瑟夫·沙赫维特; 周政一; 徐曼

    2000-01-01

    Based on the background information and the personal impression obtained during a short visit to Tarim River basin, a few problems may be defined and a proposal is presented for establishing a salinity laboratiory in the Tarim river basin of Xinjiang. The problems encountered in the Tarim river basin can be grouped into four categories: (1) Salt reclamation through leaching and resalinization following irrigation; (2) Sodicity (alkalinity) problems; (3) Impermeable subsoil layers; (4) Irrigation water salinity. In order to ensure a sustainable irrigation agriculture in Xinjiang, the water utilization efficiency for both irngation and leaching will have to be improved. The solution for the existing problems and the prevention of future problems for sustainable production requires good quantitative information. It is considered that to establish a salinity laboratory in the Tarim River basin will be not only immediately applicable to Xinjiang' s salinity problems, but its results will be valuable also for other arid regions suffering from the similar problems in China.

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

    Science.gov (United States)

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

    2009-04-01

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

  17. A land suitability system for spate irrigation schemes in Eritrea

    NARCIS (Netherlands)

    Tesfai, M.H.

    2002-01-01

    Spate irrigation is a system used for wetting land prior to planting. Use is made of seasonal rivers (wadis) producing flash floods in the uplands, which are directed by structures to irrigate fields in the lowlands. A land suitability system for spate irrigation schemes in Eritrea was studied in th

  18. Effects of Boron foliar-fertilization on irrigated soybean (Glycine max L. Merr.) in the Mississippi River Valley Delta of the midsouth, USA

    Science.gov (United States)

    Irrigated soybeans in the Mississippi Delta have been reported to with increased seed yields when fertilized with a boron (B). Furrow irrigated soybean cultivars were foliar fertilized with a B solution at growth stages R3 and/or R5. No consistent trends in yield or seed weight were noted. No phy...

  19. 渭干河灌区地下水埋深与矿化度时空分布动态%Spatial and Temporal Dynamic Distribution of Groundwater Depth and Mineralization in Weigan River Irrigation District

    Institute of Scientific and Technical Information of China (English)

    吐尔逊·艾山; 塔西甫拉提·特依拜; 买买提·阿扎提; 买买提依明·买买提

    2011-01-01

    以新疆渭干河灌区为例,利用渭干河灌区38眼监测井的1997~2007年期间地下水埋深和地下水矿化度数据,对渭干河灌区地下水位及地下水矿化度的年际变化、季节变化动态及空间分布特征及其变化原因进行初步的分析。结果表明:11 a期间,研究区春季地下水位最高,研究区地下水位从灌区上部往下部或边缘有明显的上升特征。地下水矿化度的整体趋势为灌区上游的矿化度值较低,灌区下游和边缘地区的矿化度较高。灌区年均地下水位和地下水矿化度总体上有下降趋势。%Taking Xinjiang Weigan River irrigation district as an example,38 observation wells’ data from 1997 to 2007 of groundwater depth and groundwater mineralization were used in the paper to analyze annual change of groundwater depth and the groundwater mineralization of Weigan River irrigation district,and their seasonal dynamics and spatial distribution.The results showed that in the 11 years period,the highest groundwater level appeared in spring.The groundwater level rose significantly from the top of irrigation district to the periphery of the oasis.The overall trend of groundwater mineralization is that groundwater mineralization is relatively low in the upper reaches of the irrigation district,and relatively high in the lower edge and downstream of the irrigation district.The annual groundwater depth and groundwater mineralization generally decreased in the irrigation district.

  20. CONFLICT AMONG PARTIES IN MODERNIZATION OF ECOSYSTEMS AT SUBAKS LOCATED IN BULELENG AND TABANAN REGENCIES OF BALI AT IRRIGATED BY SHABA RIVER

    Directory of Open Access Journals (Sweden)

    I Nyoman Arthanegara

    2012-11-01

    Full Text Available Conflict among parties of subak ecosystem is a conflict of interests resulting from themodernization made by political community with regard to the subculture ofpelemahan of ecosystem. The political and economic communities forcemodernization on the subak ecosystem leading to an ideological conflict betweenmodernism and the philosophy of Trihita Karana. Modernism has been responsiblefor the conflict among the parties of ecosystem in palemahan, pawongan andparhyangan of the subaks irrigated by Sabha River.Participation in group discussion, semi structured interview and transek were themethods employed in collecting the data. The triangulation including at least threerelevant theories was employed for analyzing the data.Political communities interfere with the development by applying the theoryof hegemony. The political community in collaboration with the economic communitydominates modernization which is sectoral in nature and the planning andimplementation of the development. Partial development approach, which contrastswith the theory of ecosystem (Pollunin, 1996, causes the farming community lifeprocess and the cultural values existing in the ecosystem of the subak to degrade. Theinterference of the political community in collaboration with the economiccommunity with the subak ecosystem is more dominant in the subculture ofpalemahan which is materialistic in nature so that advantages can be obtained byscience and technology. Consequently, the philosophical values of trihita karana arebroken. Such a conflict takes place due to the different interests in the subakecosystem , which is full of cultural values for the farming community. Alteration tothe land status, the imbalance between the cost spent and the yields produced and theviolation of the growing pattern are responsible for the conflict.The institution of subak, which constitutes the realization of subculture of thesubak ecosystem, is swept aside by the political and economic communities

  1. Irrigation System

    Science.gov (United States)

    1984-01-01

    Under contract with Marshall Space Flight Center, Midwest Research Institute compiled a Lubrication Handbook intended as a reference source for designers and manufacturers of aerospace hardware and crews responsible for maintenance of such equipment. Engineers of Lindsay Manufacturing Company learned of this handbook through NASA Tech Briefs and used it for supplemental information in redesigning gear boxes for their center pivot agricultural irrigation system.

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

    Science.gov (United States)

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

  3. Summary of residue analysis of biota collected for the Department of the Interior: Reconnaissance investigation of irrigation drainage in the San Juan River area, northwestern New Mexico

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — There were three primary objectives of this reconnaissance study. These objectives were: (1) to determine if DOI-sponsored irrigation projects contribute to...

  4. Assessing water salinity along River Limón and Caño San Miguel irrigation paleochannel (Maracaibo, Venezuela) as affected by the balance of soluble salts in alluvium soils

    Science.gov (United States)

    Rodriguez, Raquel; Moreno, Juan; Hermosilla, Daphne; Gascó, Antonio

    2013-04-01

    The saline degradation of soils that are irrigated with brackish water is worrisome increasing worldwide, and it may further affect the salinity of fresh water in those streams flowing across. The problem that is caused by an increasing concentration of salts that are more soluble than gypsum depends on the quality of irrigation water, climatic aridity, and drainage limitations. All these conditions meet in the alluvium soils of River Limón basin that are crossed by Caño San Miguel irrigation paleochannel. River Limón's regulation by closing Manuelote and Tulé artificial reservoirs has diminished the input of water and sediments from flooding events, which exerted dilutive effects in the past. In addition, the balance of soluble salts in these soils has also registered further net accumulation during those extremely dry years happened before 2006, because the great dilution contribution of ombrogenic dammed water coming from rain has not been enough to compensate salts concentration generated by water evapotranspiration in those irrigated soils of the middle basin, particularly in the absence of superficial runoff and deep drainage. Considering those semi-arid climate conditions prevailing in the area (annual precipitation = 710 mm; potential evapotransporation = 2361 mm), it resulted that water analyses in River Limón showed a ten-fold increased maximum annual salinity concentration (March) along the stream; that is, an electric conductivity (Ce) of 0.37 dS•m-1 (at 25 °C) at Puente Carrasquero pumping station, where water for crop irrigation is subtracted, turns to 34.60 dS•m-1 (at 25 °C) at its base level in Puerto Mara, where it discharges to Lake Maracaibo. In addition, the quality of irrigation water from Caño San Miguel, which aggregates to those coming from River Limón at the pumping station located in Carrasquero just before running through the alluvium of this water stream, resulted pretty irregular. In short, it spanned form C1 to C4 soil

  5. 干旱引黄灌区地下水位变化特征分析%Changing Characteristics of Groundwater Level of the Yellow River Irrigation Area in Arid Region

    Institute of Scientific and Technical Information of China (English)

    徐存东; 王荣荣; 丁廉营; 温钦钰; 连海东

    2016-01-01

    In order to study the changing characteristics of groundwater level of different groundwater movement zones in the arid Yellow River irrigation area, the stage I project of Jingtaichuan electrical lifting irrigation area in Gansu Province ( hereinafter called as"JID") was selected as the typical representative and the basic data was the real⁃time monitoring data of groundwater level in this area from 1982 to 2011. The inter⁃annual variation trend of groundwater level was analyzed based on Mann⁃Kendall test and the intra⁃annual variation was analyzed through the comparison of groundwater level monthly average curve of every 15 years. The results show that account for the seasonal irrigation, regional terrain and artificial exploitation, the inter⁃annual and intra⁃annual variation of different groundwater movement zones in the irrigation area has obvious difference;exploiting groundwater in groundwater accumulation zone for irrigation can effectively control the local salinization of the irrigation area.%为研究干旱引黄灌区不同地下水运动带的地下水位变化特征,以甘肃省景电一期灌区为例,利用其1982—2011年实测地下水位数据,采用Mann-Kendall趋势检验法分析了地下水位的年际变化趋势,并根据每15 a逐月的地下水位均值曲线,对地下水位的年内变化特征进行了研究。结果表明:受季节性灌溉、区域地势、人为开采等因素的影响,不同地下水运动带地下水位年际、年内变化趋势存在较大差异;在灌区汇水区域适当发展井灌,有利于土地盐渍化的控制。

  6. Water accounting for conjunctive groundwater and surface water irrigation sources:A case study in the middle Heihe River Basin of arid northwestern China

    Institute of Scientific and Technical Information of China (English)

    XueXiang Chang; Bing Liu; Hu Liu; ShouBo Li

    2015-01-01

    Oases in arid northwestern China play a significant role in the region's economic stability and development. Overex-ploitation of the region's water resources has led to serious environmental consequences. In oases, irrigated agriculture is the primary consumer of water, but water shortages resulting from dramatically growing human needs have become a bottleneck for regional sustainable development, making effective management of the limited available water critical. Effective strategies must be formulated to increase agricultural productivity while reducing its environmental impacts. To support the development of such strategies, water use patterns were analyzed during the 2007 and 2008 growing seasons, from May to early October, to identify opportunities for improving water management using the Mold-en-Sakthivadivel water-accounting method, which combines groundwater and surface water into a single domain and can provide a good estimate of the uses, depletion, and productivity of water in a water basin context. The study area lies in Linze County, Gansu Province, China. In the study area, the inflow water resources consist of irrigation, precipita-tion, and soil water, which accounted for 89.3%, 8.9%, and 1.8% of the total in 2007, and 89.3%, 4.8%, and 5.9% in 2008, respectively. The irrigation depends heavily on groundwater, which accounted for 82.1% and 83.6% of the total irrigation water in 2007 and 2008, respectively. In 2007 and 2008, deep percolation accounted for 50.1% and 47.9% of the water outflow, respectively, with corresponding depleted fractions of 0.51 and 0.55, respectively. For the irrigation district as a whole, the water productivity was only 1.37 CNY/m3. To significantly increase crop water productivity and prevent depletion of the region's groundwater aquifer, it will be necessary to reduce the amount of water used for ir-rigation. Several water-saving agricultural practices are discussed and recommended.

  7. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Artificial Drainage (1992) and Irrigation (1997)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the estimated area of artifical drainage for the year 1992 and irrigation types for the year 1997 compiled for every MRB_E2RF1...

  8. Estimation of net groundwater use in irrigated river basins using geo-information techniques : a case study in Rechna Doab, Pakistan

    NARCIS (Netherlands)

    Ahmad, M.D.

    2002-01-01

    Keywords: remote sensing, GIS, water balance, groundwater, net groundwater use, recharge, water management, Rechna Doab, Pakistan.

    Over-exploitation of groundwater resources threatens the future of irrigated agriculture, especially in the arid and semi-arid regions of the world. In

  9. Estimation of net groundwater use in irrigated river basins using geo-information techniques. A case study in Rechna Doab, Pakistan

    NARCIS (Netherlands)

    Mobin-ud-Din Ahmad,

    2002-01-01

    Keywords: remote sensing, GIS, water balance, groundwater, net groundwater use, recharge, water management, Rechna Doab, Pakistan.Over-exploitation of groundwater resources threatens the future of irrigated agriculture, especially in the arid and semi-arid regions of the world. In order to reverse t

  10. 黑河中游灌区水化学空间变异特征%Hydrochemical characteristics of the irrigation area in the middle reaches of the Heihe River Basin

    Institute of Scientific and Technical Information of China (English)

    郜银梁; 陈军锋; 张成才; 闫云霞

    2011-01-01

    Located in the central part of the Hexi Corridor(37°45 ' ~42°40'N,97°42' ~ 102°04'E) ,the Heihe River watershed is the second largest one in land river watershed in the arid area of northwest China. The exchange of surface water and groundwater takes place two or three times in this area. It is essential to analyze the interaction between groundwater and surface water, so as to use water resources effectively and predict the change in the water environment. Hydrochemical and isotopic methods of water is one of the important ways, so it is necessary to carry out in-depth analysis and research on chemical characteristics of groundwater and surface water for the study area. Spatial variations of hydrochemical types and the hydrochemical characteristics for both surface water and groundwater were explored in the irrigation area of the middle reaches of the Heihe River Basin. Water of the main profile a-long the Heihe River and its main tributaries liyuan River and Shandan River was analyzed for pH, TDS and the major ions in the middle reaches from the Yingluo Gorge to the Zhengyi Gorge, and the similarities and differences of water chemistry between the river and its tributaries were set up. Thirty-nine shallow groundwater samples (confined water samples and unconfined water samples) were collected from agricultural irrigation wells and domestic wells for chemical measurement all over the irrigation area of the basin. Some chemical indicators such as pH, TDS, conductivity (EC) and temperature were measured in the field, and main anions and cations were measured in the laboratory of Institute of Geographic Sciences and Natural Resources Research, CAS. As a management and decision tool, the method of geostatistics has been widely applied to study the spatial changes of groundwater geo-chemical characteristics. So the TDS and pH of the groundwater samples were analyzed using Ordinary Kriging interpolation. Types of hydrochemical features of surface water and

  11. DEVELOPMENT OF WATER CIRCULATION MODEL INCLUDING IRRIGATION

    Science.gov (United States)

    Kotsuki, Shunji; Tanaka, Kenji; Kojiri, Toshiharu; Hamaguchi, Toshio

    It is well known that since agricultural water withdrawal has much affect on water circulation system, accurate analysis of river discharge or water balance are difficult with less regard for it. In this study, water circulation model composed of land surface model and distributed runoff model is proposed at 10km 10km resolution. In this model, irrigation water, which is estimated with land surface model, is introduced to river discharge analysis. The model is applied to the Chao Phraya River in Thailand, and reproduced seasonal water balance. Additionally, the discharge on dry season simulated with the model is improved as a result of including irrigation. Since the model, which is basically developed from global data sets, simulated seasonal change of river discharge, it can be suggested that our model has university to other river basins.

  12. Characteristics of lead geochemistry and the mobility of Pb isotopes in the system of pedogenic rock-pedosphere-irrigated riverwater-cereal-atmosphere from the Yangtze River delta region, China.

    Science.gov (United States)

    Wang, Cheng; Wang, Jianhua; Yang, Zhongfang; Mao, Changping; Ji, Junfeng

    2013-11-01

    Knowledge of the characteristics of Pb and its isotopic transfer in different compartments is scant, especially for the mobility of Pb isotopes in the geochemical cycle. The present study characterizes differential Pb transport mechanism and the mobility of Pb isotopes in the pedogenic parent rock-pedosphere-irrigated riverwater-cereal-atmosphere system in the Yangtze River delta region, by determining Pb concentration and Pb isotopic ratios of pedogenic parent rocks, fluvial suspended particle matter, tillage soils, soil profiles, irrigated riverwater, fertilizer, Pb ore, cereal roots and grains. The results show that Pb isotopes in the geochemical cycle generally follow the equation of (208)Pb/(206)Pb=-1.157×(206)Pb/(207)Pb+3.46 (r(2)=0.941). However, Pb isotopes have different mobility in different environmental matrixes. Whereas in the pedosphere, the heavier Pb ((208)Pb) usually shows stronger mobility relative to the lighter Pb, and is more likely to transfer into soil exchangeable Pb fraction and carbonates phase. The lighter Pb shows stronger transfer ability from soil to cereal grain via root compared to the heavier Pb. However, the cereal grains have lower (206)Pb/(207)Pb and higher (208)Pb/(206)Pb ratios than root and tillage soil, similar to the airborne Pb and anthropogenic Pb, implying that a considerable amount of Pb in cereal grains comes from the atmosphere. The estimate model shows that 16.7-52.6% (average: 33.5%) of Pb in rice grain is the airborne Pb.

  13. 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...

  14. 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...

  15. small scale irrigation management practices: a study of fadama

    African Journals Online (AJOL)

    The irrigation management practices of the fadama farmers along the Asa river in Ilorin was investigated in this study. ... consideration as an integral part of strategy aimed at increasing productivity. .... of simple farm tools like hoe, and cutlass.

  16. Bioaccumulation and associated dietary risks of Pb, Cd, and Zn in amaranth (Amaranthus cruentus) and jute mallow (Corchorus olitorius) grown on soil irrigated using polluted water from Asa River, Nigeria.

    Science.gov (United States)

    Ogunkunle, Clement Oluseye; Ziyath, Abdul M; Adewumi, Faderera Esther; Fatoba, Paul Ojo

    2015-05-01

    Dietary uptake of heavy metals through the consumption of vegetables grown on polluted soil can have serious human health implications. Thus, the study presented in this paper investigated the bioaccumulation and associated dietary risks of Pb, Zn, and Cd present in vegetables widely consumed in Nigeria, namely amaranth and jute mallow, grown on soil irrigated with polluted water from Asa River. The study found that the soil was polluted with Zn, Pb, and Cd with Pb and Cd being contributed by polluted river, while Zn was from geogenic sources. The metal concentration in amaranth and jute mallow varied in the order of Zn > Pb > Cd and Zn > Pb ≈ Cd, respectively. Jute mallow acts as an excluder plant for Pb, Cd, and Zn. Consequently, the metal concentrations in jute mallow were below the toxic threshold levels. Furthermore, non-cancer human health risk of consuming jute mallow from the study site was not significant. In contrast, the concentrations of Pb and Cd in amaranth were found to be above the recommended safe levels and to be posing human health risks. Therefore, further investigation was undertaken to identify the pathways of heavy metals to amaranth. The study found that the primary uptake pathway of Pb and Cd by amaranth is foliar route, while root uptake is the predominant pathway of Zn in amaranth.

  17. Sun and Sun Worship in Different Cultures

    Science.gov (United States)

    Farmanyan, S. V.; Mickaelian, A. M.

    2014-10-01

    The Sun symbol is found in many cultures throughout history, it has played an important role in shaping our life on Earth since the dawn of time. Since the beginning of human existence, civilisations have established religious beliefs that involved the Sun's significance to some extent. As new civilisations and religions developed, many spiritual beliefs were based on those from the past so that there has been an evolution of the Sun's significance throughout cultural development. For comparing and finding the origin of the Sun we made a table of 66 languages and compared the roots of the words. For finding out from where these roots came from, we also made a table of 21 Sun Gods and Goddesses and proved the direct crossing of language and mythology.

  18. Sun's rap song

    Science.gov (United States)

    Hogan, M.; Lee, W.

    1995-07-01

    We present a rap song composed for the Sun, our star. This Sun's Rap Song can be utilized in classroom teaching to spark the students' interest and facilitate the students' learning of the relevant subjects.

  19. MedSun Reports

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medical Product Safety Network (MedSun) is an adverse event reporting program launched in 2002. The primary goal for MedSun is to work collaboratively with the...

  20. MedSun Reports

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medical Product Safety Network (MedSun) is an adverse event reporting program launched in 2002. The primary goal for MedSun is to work collaboratively with the...

  1. Research on real-time monitoring of water diverting quantity in inner mongolia loop area of Yellow River irrigation district%内蒙古河套灌区引黄水量实时监测研究

    Institute of Scientific and Technical Information of China (English)

    蒋秀华; 钱云平; 蒋昕晖; 何炜; 周建波

    2001-01-01

    The contradiction of water resources scarcity is extremely prominent in Yellow River drainage basin at present. For the purpose of achieve sustainable development stratagem and develop social economy of Yellow River drainage basin, it is pre-requisite that settle the problem of water resources. The reasonable collocation and optimized scheduling of water resources have already been the important problem that needed impending to study and to solve. In order to carry through efficient the water resources real-time scheduling, it is necessary to study the feasibility of real-time monitoring of water diverting quantity. The varying and characteristic of observed runoff and water quantity in Inner Mongolia loop area of Yellow River irrigation district are analyzed, preliminary research of water quantity real-time monitoring is implemented, and the existent problem is discussed.%黄河流域水资源紧缺矛盾非常突出,为实现黄河流域可持续发展战略,发展沿黄地区社会经济,必须解决水资源问题。水资源合理配置、优化调度,已成为急需研究和解决的重要问题。为能有效地进行水资源实时调度,有必要对引黄水量实时监测可行性进行研究。本文在对内蒙古河套灌区实测径流量、引黄水量的变化和特点研究分析的基础上,对引黄水量实时监测进行了初步研究,并就存在问题作了讨论。

  2. Seasons by the Sun

    Science.gov (United States)

    Stark, Meri-Lyn

    2005-01-01

    Understanding the Sun has challenged people since ancient times. Mythology from the Greek, Inuit, and Inca cultures attempted to explain the daily appearance and nightly disappearance of the Sun by relating it to a chariot being chased across the sky. While people no longer believe the Sun is a chariot racing across the sky, teachers are still…

  3. Personal, Seasonal Suns

    Science.gov (United States)

    Sutley, Jane

    2010-01-01

    This article presents an art project designed for upper-elementary students to (1) imagine visual differences in the sun's appearance during the four seasons; (2) develop ideas for visually translating their personal experiences regarding the seasons to their sun drawings; (3) create four distinctive seasonal suns using colors and imagery to…

  4. Nile River Irrigation Project and State Governance in Ancient Egypt:Also on the Formation and Social Form of Ancient Egyptian Civilization%尼罗河灌溉工程与古埃及的国家治理--兼论古埃及文明的形成与社会形态

    Institute of Scientific and Technical Information of China (English)

    李怡净

    2016-01-01

    古埃及是一个典型的以河流为中心的国家,水利灌溉在其农业发展中起着重要的作用。主要河流尼罗河的定期泛滥不仅对周边耕地进行了“自然灌溉”,同时还给河流周边带来大量肥沃的土壤,为古埃及农业发展提供了得天独厚的条件。文章基于尼罗河自然灌溉和水利灌溉的思考,探究水利灌溉工程对古埃及经济社会所产生的一系列重大影响以及在农业生活中不可替代的作用。%Ancient Egypt is a typical state focused on river because irrigation plays a very important role in the agricultural development of this country. Periodic flooding of its major river Nile irrigates the cultivated lands close to it and brings a lot of fertile soil there, which creates exceptionally good conditions for agricultural development in Ancient Egypt. This paper studies the natural irrigation and water conservancy irrigation along the Nile River,investigates the important influences of water conservancy irrigation on economy and society and its irreplaceable role in agricultural life.

  5. 宁夏黄河灌区农业非点源污染损失估算%Economic loss caused by non-point source pollution ——A case study of Ningxia Yellow River Water Irrigation District

    Institute of Scientific and Technical Information of China (English)

    杨引禄; 冯永忠; 杨世琦; 曹艳春; 刘强; 杨改河

    2011-01-01

    Non-point source pollution have become more and more serious and brought enormous danger to water environment in Ningxia Yellow River Water Irrigation District, so it has important significance for ecological security to esti-mate the economic value of losses of pollution load in this area. In this paper, according to the JOHNES export coefficient method, calculation is made of non-point source pollution load in'Ningxia Yellow River Water Irrigation District, and the methoddology of enxironmental economics is used to reckon quantitatively economic loss caused by agricultural non-point source pollution. The results showed that the livestock breeding pollution contributed 41.27% to the pollution load of the area, and 37.25 % to the TN and 4.03 % to the TP pollution load of the area. The planting was the second and the rural domestic waste was the lowest proportion in non-point source pollution load, which was 34.54% and 24.2% to the pollution load of the area. The economic loss caused by the regional non-point source pollution was calculated at about 548.741 million RMB in total, of which about 40.97% was coutributed by livestock breeding pollution, while the planting and the rural areaa domestic waste respectively 35.6% and 23.4% to the all economic loss. This results illuminate that only the control of livestock breeding pollution can reduce economic loss caused by agricultural ono-point source pollution in Ningxia Yellow River Water Irrigation District.%以宁夏黄河灌区为研究区,在充分利用JOHNES输出系数法计算灌区非点源污染负荷的基础上,应用环境经济学中的恢复防护费用法对灌区农业非点源污染产生的负荷转化为经济损失进行估算.结果表明:宁夏黄河灌区禽畜养殖产生的污染负荷最高,占灌区污染负荷的41.27%,其中全氮排放占整个区域污染负荷的37.25%,全磷排放占整个区域污染负荷的4.03%,种植业产生的氮磷污染负荷次之,居民生活

  6. Crop water parameters of irrigated wine and table grapes to support water productivity analysis in the Sao Francisco river basin, Brazil

    NARCIS (Netherlands)

    Castro Teixeira, de A.H.; Bastiaanssen, W.G.M.; Bassoi, L.H.

    2007-01-01

    Energy and water balance parameters were measured in two commercial vineyards in the semiarid region of the São Francisco river basin, Brazil. Actual evapotranspiration (ET) was acquired with the Bowen ratio surface energy balance method. The ratio of the latent heat flux to the available energy, or

  7. Ghana - Agriculture - Irrigation

    Data.gov (United States)

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

  8. WATER REQUIREMENT OF IRRIGATED GARLIC

    Science.gov (United States)

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

  9. Water Requirements Of Irrigated Garlic

    Science.gov (United States)

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

  10. 甘肃引黄灌区典型天然群落分布特征%Distribution of Typical Natural Communities in the Yellow River Irrigation Area in Gansu Province

    Institute of Scientific and Technical Information of China (English)

    李亚; 王辉; 魏怀东; 纪永福; 周兰萍; 胡小柯; 肖斌

    2013-01-01

    Through investigation on typical natural vegetation communities in Yellow River Irrigation Area in Gansu Province ,the distribution characteristics of the main population were studied .Result shows that :(1) the typical population of main natural populations in Yellow River Irrigation Area are Oxytropis aciphylla ,Nitraria tanguto-rum & A rtemisia ordosica;(2) site conditions & soil characteristics of three different populations are significantly different ,A rtemisia ordosica being fixed dunes ,Oxytropis aciphylla being fixed & semi-fixed sand dunes ,popula-tion of Nitraria tangutorum being semi-fixed sand dunes ;its pH value & total salt from high to low is as follows :Nitraria tangutorum ,Oxytropis aciphylla ,A rtemisia ordosica;(3) there are 29 plant species in the study area ,be-longing to 10 families and 26 genera ,of which five kinds of shrubs or small shrubs ,accounting for 17 .24% of plant species ;(4) the vegetation in study area shows characteristics of simple structure ,single & fewer species in shrub layer ,larger number of species & relative abundance in herbaceous layer .%通过对甘肃引黄灌区典型天然植被群落调查,研究了主要种群的分布特征。结果表明:(1)甘肃引黄灌区主要天然群落内典型的种群有猫头刺、白刺和油蒿;(2)3个不同种群立地条件和土壤特征差异显著,油蒿种群为固定沙丘,猫头刺种群为固定、半固定沙丘,白刺种群为半固定沙丘,其pH值和全盐量从高至低依次为:白刺、猫头刺、油蒿;(3)研究区共有植物种29种,隶属10个科26个属,其中灌木或小灌木5种,占植物种数的17.24%;(4)研究区植被整体表现出了结构简单,灌木层物种相对单一且数量较少,草本层物种相对丰富且数量较大的特征。

  11. A Real-time Irrigation Forecasting System in Jiefangzha Irrigation District, China

    Science.gov (United States)

    Cong, Z.

    2015-12-01

    In order to improve the irrigation efficiency, we need to know when and how much to irrigate in real time. If we know the soil moisture content at this time, we can forecast the soil moisture content in the next days based on the rainfall forecasting and the crop evapotranspiration forecasting. Then the irrigation should be considered when the forecasting soil moisture content reaches to a threshold. Jiefangzha Irrigation District, a part of Hetao Irrigation District, is located in Inner Mongolia, China. The irrigated area of this irrigation district is about 140,000 ha mainly planting wheat, maize and sunflower. The annual precipitation is below 200mm, so the irrigation is necessary and the irrigation water comes from the Yellow river. We set up 10 sites with 4 TDR sensors at each site (20cm, 40cm, 60cm and 80cm depth) to monitor the soil moisture content. The weather forecasting data are downloaded from the website of European Centre for Medium-Range Weather Forecasts (ECMWF). The reference evapotranspiration is estimated based on FAO-Blaney-Criddle equation with only the air temperature from ECMWF. Then the crop water requirement is forecasted by the crop coefficient multiplying the reference evapotranspiration. Finally, the soil moisture content is forecasted based on soil water balance with the initial condition is set as the monitoring soil moisture content. When the soil moisture content reaches to a threshold, the irrigation warning will be announced. The irrigation mount can be estimated through three ways: (1) making the soil moisture content be equal to the field capacity; (2) making the soil moisture saturated; or (3) according to the irrigation quota. The forecasting period is 10 days. The system is developed according to B2C model with Java language. All the databases and the data analysis are carried out in the server. The customers can log in the website with their own username and password then get the information about the irrigation forecasting

  12. Haw River PFCs Data Set

    Data.gov (United States)

    U.S. Environmental Protection Agency — PFAS concentrations in river and drinking water in and around the Haw River in North Carolina. This dataset is associated with the following publication: Sun, M., E....

  13. Study on main techniques of water and sediment resources allocation in irrigation system of the Lower Yellow River%引黄灌区水沙资源配置技术的研究

    Institute of Scientific and Technical Information of China (English)

    卢红伟; 王延贵; 史红玲

    2012-01-01

    The main techniques of water and sediment resources allocation in irrigation system of the Lower Yellow River were summarized, which includes the sediment reduction and sediment sinking technique, water and sediment transport technique, water and sediment diversion teehniqueetc. The sediment reduction and harmful sediment control are stated based on the harmful sediment concept in the irrigation system, of which the former will be realized on controlling diversion sediment concentration or water diversion reduction, and the latter will become true based on the harmful sediment interception and settlement. The structural and non-structural measures for enhancing the sediment transport capacity of the canal are summed through analysis, of which the former includes the slope increase, canal liner, improvement of the flow block bridges and optical cross-section, and the latter consists mainly of water and sediment controlling techniques. The water and sediment diversion characteristics of the gravity irrigation and pumping irrigation were analyzed in theory. When the diversion sediment concentration by gravity in branch canal is less than that in trunk canal, the trunk canal will be in status of deposition increase. When the pumping station and its inlet are arranged suitably, it is good at deposition decrease in the trunk canal.%引黄灌区水沙资源配置关键技术包括灌区减沙沉沙技术、引水分沙技术、渠道输水输沙技术等。通过引黄灌区引沙和沉沙资料的分析,总结了灌区减沙技术和有害泥沙拦沉技术,减沙主要是通过控制引水含沙量或减少引水量来实现,有害泥沙的拦沉主要是利用渠道拦沙设施和沉沙池拦截和沉积有害的粗颗粒泥沙。结合渠道输水输沙能力,分析了提高灌渠输沙能力的工程措施和非工程措施,工程措施包括加大渠道比降、渠道衬砌、改造阻水建筑物、优化断面等,非工程措施主要是指水沙调

  14. [Distribution of soil heavy metal and pollution evaluation on the different sampling scales in farmland on Yellow River irrigation area of Ningxia: a case study in Xingqing County of Yinchuan City].

    Science.gov (United States)

    Wang, You-Qi; Bai, Yi-Ru; Wang, Jian-Yu

    2014-07-01

    Determining spatial distributions and analyses contamination condition of soil heavy metals play an important role in evaluation of the quality of agricultural ecological environment and the protection of food safety and human health. Topsoil samples (0-20 cm) from 223 sites in farmland were collected at two scales of sampling grid (1 m x 1 m, 10 m x 10 m) in the Yellow River irrigation area of Ningxia. The objectives of this study were to investigate the spatial variability of total copper (Cu), total zinc (Zn), total chrome (Cr), total cadmium (Cd) and total lead (Pb) on the two sampling scales by the classical and geostatistical analyses. The single pollution index (P(i)) and the Nemerow pollution index (P) were used to evaluate the soil heavy metal pollution. The classical statistical analyses showed that all soil heavy metals demonstrated moderate variability, the coefficient of variation (CV) changed in the following sequence: Cd > Pb > Cr > Zn > Cu. Geostatistical analyses showed that the nugget coefficient of Cd on the 10 m x 10 m scale and Pb on the 1 m x 1 m scale were 100% with pure nugget variograms, which showed weak variability affected by random factors. The nugget coefficient of the other indexes was less than 25%, which showed a strong variability affected by structural factors. The results combined with P(i) and P indicated that most soil heavy metals have slight pollution except total copper, and in general there were the trend of heavy metal accumulation in the study area.

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

    Science.gov (United States)

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

    2014-05-01

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

  16. Sun为eCommerce提供高可用性平台--记电子商务外包资源领先提供商Digital River对Sun平台的选用%Provision of Highly Applicable Platform by Sun for E-Commerce:Selection of Sun Platform by Digital River, the Leading Supplier of E-Commerce Resources

    Institute of Scientific and Technical Information of China (English)

    SUN公司北京分公司

    2004-01-01

    @@ Digital River公司是全球领先的电子商务外包资源提供商,在Sun StorEdge 9960磁盘阵列、Sun Fire 6800服务器,以及Sun 420R/280R架装式服务器等系统的采用,成功地提高了网络系统的性能,并扩展了客户服务项目.

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

    Science.gov (United States)

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

    2015-04-01

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

  18. Root canal irrigants.

    Science.gov (United States)

    Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

    2010-10-01

    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 discussed. We performed a Medline search for English-language papers published untill July 2010. The keywords used were 'root canal irrigants' and 'endodontic irrigants.' The reference lists of each article were manually checked for additional articles of relevance.

  19. [Effects of different fertilization measures on N2O emission in oil sunflower field in irrigation area of upper Yellow River].

    Science.gov (United States)

    Chen, Zhe; Chen, Yuan-yuan; Gao, Ji; Liu, Ru-liang; Yang, Zheng-li; Zhang, Ai-ping

    2015-01-01

    Agricultural soil has become the largest anthropogenic source of atmospheric nitrous oxide (N20). To estimate the impacts of long-term combined application of organic and inorganic fertilizers on N20 emission in a typical winter wheat-oil sunflower cropping system in the Ningxia irrigation area, we measured N20 fluxes using the static opaque chamber-gas chromatograph method and monitored the seasonal dynamics of related factors. Our results showed that nitrogen addition in the previous crop field significantly stimulated N2O emissions during the following oil-sunflower cultivation, and the mean fluxes of N300-OM, N240-OM1/2, N300 and N240 were (34.16 ± 9.72), (39.69 ±10.70), (27.75 ±9.57) and (26.30 ± 8.52) µg . m-2 . h-1, respectively, which were 4.09, 4.75, 3.32 and 3.15 times of the control groups. The total cumulative N2O emissions of fertilizer treatments in growing season was as high as 796.7 to 1242.5 g . hm-2, which was 2.99 to 4.67 times of the control groups. During the growing season, the rates of N2O emission in each month organic and inorganic fertlizers combined treatments were similar at high levels. N2O emission in chemical fertilizer treatments gradually decreased, and the main period of N2O emission occurred at the beginning of growing season. Taking July for example, N2O emission accounted for 41.3% to 41. 8% of total cumulative amount. The amounts of N20 emission under organic and inorganic fertilizers combined treatments were significantly higher than under chemical fertilizer treatments. The N2O emissions were not significantly different between conventional and optimized applications of nitrogen fertilizer under the same fertilizing method, either between N300-OM and N240-OM1/2, or between N300 and N240. On account of the drought, N2O emission in each treatment was mainly affected by soil moisture. N2O emission had a significant positive correlation with soil ammonium nitrogen content under combined applications of organic and inorganic

  20. River

    Directory of Open Access Journals (Sweden)

    Morel Mathieu

    2016-01-01

    Full Text Available The OECD report “Boosting Resilience through Innovative Risk Governance” examines the efforts of OECD countries to prevent or reduce future disaster impacts, and highlights several key areas where improvements can be made. International collaboration is insufficiently utilised to address shocks that have increasingly global consequences. Institutional design plays a significant role in facilitating or hampering the engagement and investments of governmental and non-governmental stakeholders in disaster risk prevention and mitigation. To inform the design of “better” institutions, the OECD proposes the application of a diagnostic framework that helps governments identify institutional shortcomings and take actions to improve them. The goal of the case study on the Rhone River is to conduct an analysis of the progress, achievements and existing challenges in designing and implementing disaster risk reduction strategies through the Rhone Plan from a comparative perspective across a set of selected countries of this study, like Austria and Switzerland, will inform how to improve institutional frameworks governing risk prevention and mitigation. The case study will be used to identify examples of successful practice taking into account their specific country contexts, and analyse their potential for policy transfer.

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

    Science.gov (United States)

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

    2016-04-01

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

  2. Armenia - Irrigation Infrastructure

    Data.gov (United States)

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

  3. Demanda de irrigação da cultura da uva na Bacia do Rio São Francisco Irrigation demand for grape crop in San Francisco River Basin

    Directory of Open Access Journals (Sweden)

    Wallisson da S. Freitas

    2006-09-01

    Full Text Available Visando subsidiar o planejamento de projetos agrícolas para o dimensionamento de projetos de irrigação e a gestão de recursos hídricos, estimou-se e se espacializou a demanda de irrigação da videira (Vitis vinifera L., cv. Itália, na bacia do Rio São Francisco. Utilizaram-se séries históricas de dados de 81 estações climáticas distribuídas na bacia. Para cada estação calculou-se os valores, máximos diários e o total anual, da evapotranspiração de referência (ETo, da evapotranspiração da cultura (ETc, da demanda suplementar da cultura e da demanda suplementar de irrigação (este com eficiência de 70%. Com base nos resultados obtidos, concluiu-se que: (a a ETc máxima diária variou, em grande parte da bacia, de 4,5 a 5,7 mm d-1, tendo média anual de 943 mm; (b em média, a demanda anual suplementar da cultura foi 839,5 mm, equivalente a 103,5 mm inferior à ETc; (c o fato do sistema funcionar com 70% de eficiência, em vez de 90%, implica em acréscimo estimado de 18.808.755 m³ de água por ano, somente nas microrregiões de Juazeiro, BA e Petrolina, PE.The irrigation water demand of the grapevine (Vitis vinifera L. cv. Italy was estimated and spatialized in San Francisco River Basin, in order to subsidize the agricultural project planning and water resource management. Historical data series relative to 81 climatic stations distributed throughout the basin were used. The maximum daily values and the annual total values of the reference evapotranspiration (ETo, crop evapotranspiration (ETc, supplementary demand of the crop and the supplementary irrigation demand (70% efficiency were calculated for each station. According to the results, the following conclusions were drawn: (a in a large area of the basin, the maximum daily ETc varied from 4.5 to 5.7 mm d-1, with an annual mean of 943 mm; (b the supplementary annual demand of the crop averaged 839.5 mm, corresponding to 103.5 mm less than ETc; and (c the irrigation

  4. Sun-Earth Days

    Science.gov (United States)

    Thieman, J.; Ng, C.; Lewis, E.; Cline, T.

    2010-08-01

    Sun-Earth Day is a well-coordinated series of programs, resources and events under a unique yearly theme highlighting the fundamentals of heliophysics research and missions. A menu of activities, conducted throughout the year, inspire and educate participants. Sun-Earth Day itself can vary in date, but usually is identified by a celebration on or near the spring equinox. Through the Sun-Earth Day framework we have been able to offer a series of coordinated events that promote and highlight the Sun, its connection to Earth and the other planets. Sun-Earth Day events are hosted by educators, museums, amateur astronomers and scientists and occur at schools, community groups, parks, planetaria and science centers around the globe. Sun-Earth Day raises the awareness and knowledge of formal and informal education audiences concerning space weather and heliophysics. By building on the success of Sun-Earth Day yearly celebrations, we seek to affect people of all backgrounds and ages with the wonders of heliophysics science, discovery, and exploration in ways that are both tangible and meaningful to their lives.

  5. Irrigation water quality assessments

    Science.gov (United States)

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

  6. Irrigation Systems. Student's Guide.

    Science.gov (United States)

    Amarillo Coll., TX.

    This guide is intended for use by individuals preparing for a career in commercial and residential irrigation. The materials included are geared toward students who have had some experience in the irrigation business; they are intended to be presented in 10 six-hour sessions. The first two sections deal with using this guide and preparing for the…

  7. Irrigation Systems. Instructor's Guide.

    Science.gov (United States)

    Amarillo Coll., TX.

    This guide is intended for use by licensed irrigators who wish to teach others how to design and install residential and commercial irrigation systems. The materials included in the guide have been developed under the assumption that the instructors who use it have little or no formal training as teachers. The first section presents detailed…

  8. Irrigation Without Waste

    Science.gov (United States)

    Shea, Kevin P.

    1975-01-01

    A new means of irrigation, called the drip or trickle system, has been proven more efficient and less wasteful than the current system of flood irrigation. As a result of this drip system, fertilizer-use efficiency is improved and crop yield, though never decreased, is sometimes increased in some crops. (MA)

  9. Sun and Sjogren's Syndrome

    Science.gov (United States)

    Patient Education Sheet The Sun and Sjögren’s Syndrome The SSF thanks Mona Z. Mofid, MD, FAAD, Diplomate, American Board of Dermatology, and Medical Director, American Melanoma Foundation, San Diego, California, ...

  10. Why Study the Sun?

    Indian Academy of Sciences (India)

    Arvind Bhatnagar

    2006-06-01

    In this presentation we briefly describe the Sun through large number of illustrations and pictures of the Sun taken from early times to the present day space missions. The importance of the study of the Sun is emphasized as it is the nearest star which presents unparallelled views of surface details and numerous phenomena. Our Sun offers a unique celestial laboratory where a large variety of phenomena take place, ranging in temporal domain from a few milliseconds to several decades, in spatial domain from a few hundred kilometers to thousands of kilometers, and in the temperature domain from a few thousand degrees to several million degrees. Its mass motion ranges from thousandths to thousands of kilometers per second. Such an object provides us with a unique laboratory to study the state of matter in the Universe. The existing solar ground-based and space missions have already revealed several mysteries of the outer environment of our Sun and much more is going to come in the near future from planned new sophisticated ground-based solar telescopes and Space missions. The new technique of helioseismology has unravelled many secrets of the solar interior and has put the Standard Solar Model (SSM) on firm footing. The long-standing problem of solar neutrinos has been recently sorted out, and even the ‘back side’ view of the Sun can be seen using the technique of holographic helioseismology.

  11. The Sun and Earth

    Science.gov (United States)

    Gopalswamy, Natchimuthuk

    2012-01-01

    Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

  12. Impact of urban contamination of the La Paz River basin on thermotolerant coliform density and occurrence of multiple antibiotic resistant enteric pathogens in river water, irrigated soil and fresh vegetables.

    Science.gov (United States)

    Poma, Violeta; Mamani, Nataniel; Iñiguez, Volga

    2016-01-01

    La Paz River in Andean highlands is heavily polluted with urban run-off and further contaminates agricultural lowlands and downstream waters at the Amazon watershed. Agricultural produce at this region is the main source of vegetables for the major Andean cities of La Paz and El Alto. We conducted a 1 year study, to evaluate microbial quality parameters and occurrence of multiple enteropathogenic bacteria (Enterohemorrhagic E. coli-EHEC, Enteroinvasive E. coli or Shigella-EIEC/Shigella, Enteroaggregative E. coli-EAEC, Enteropathogenic E. coli-EPEC Enterotoxigenic E. coli-ETEC and Salmonella) and its resistance to 11 antibiotics. Four sampling locations were selected: a fresh mountain water reservoir (un-impacted, site 1) and downstream sites receiving wastewater discharges (impacted, sites 2-4). River water (sites 1-4, N = 48), and soil and vegetable samples (site 3, N = 24) were collected during dry (April-September) and rainy seasons (October-March). Throughout the study, thermotolerant coliform density values at impacted sites greatly exceeded the guidelines for recreational and agricultural water uses. Seasonal differences were found for thermotolerant coliform density during dry season in water samples nearby a populated and hospital compound area. In contrast to the un-impacted site, where none of the tested enteropathogens were found, 100 % of surface water, 83 % of soil and 67 % of vegetable samples at impacted sites, were contaminated with at least one enteropathogen, being ETEC and Salmonella the most frequently found. ETEC isolates displayed different patterns of toxin genes among sites. The occurrence of enteropathogens was associated with the thermotolerant coliform density. At impacted sites, multiple enteropathogens were frequently found during rainy season. Among isolated enteropathogens, 50 % were resistant to at least two antibiotics, with resistance to ampicillin, nalidixic acid, trimethoprim-sulfamethoxazole and tetracycline commonly

  13. Storage and Spatial Distribution of Soils Carbon in Lower Reaches of the Yellow River Irrigation District%黄河下游灌区土壤碳储量及碳密度分布

    Institute of Scientific and Technical Information of China (English)

    赵广帅; 李运生; 高静; 李发东

    2014-01-01

    Soil carbon, particularly the organic form (SOC), exerts an important role in crop production and the mitigation of greenhouse gas emissions. So a better understanding of SOC storage and the variability in SOC distribution will contribute a lot to sustainable development of regional ecological environments and agriculture. As an important grain and cotton production base, the Yellow River irrigated district has irrigation history of more than 50 years, and there is no doubt that long-term irrigation has changed in regional soil C storage and distribution. Previous study on soil C estimates are more conducted in larger scale, and the results often appear quite different due to the amount of sampling and the complexity of the regional variation in environmental factors, moreover there are less studies concerning to long-term influence of large-scale irrigation on soil C distribution, particularly in the lower Yellow River irrigated district. In this study, we collected relevant statistical data, soil and hydrological data and so on, taken samples from 7 layers of soil with a depth of 1 m (0~5 cm、5~10 cm、10~20 cm、20~40 cm、40~60 cm、60~80 cm、80~100 cm), using GIS spatial interpolation and spatial statistical methods, aimed at generalizing C storage and soil carbon density (CD) distribution characteristics in different depth or under different land uses and different soil types, so as to providing the basis for the development of ecological agriculture under long-term irrigation conditions in the study area. The study results are as follows:total carbon storage (TC) to 1 m soil depth was 1 045.13 Tg, and soil organic carbon storage (SOC) amounted to 815.76 Tg, with proportions of 23.44%, 20.06%, 18.95%, 18.83%, and18.72%held at soil depths of 0~20 cm, 20~40 cm, 40~60 cm, 60~80 cm, and 80~100 cm respectively. Estimated SOC in cultivated and uncultivated lands were approximately 610 Tg and 18.99 Tg respectively, while grassland and forested land held just 25

  14. Irrigation in endodontics.

    Science.gov (United States)

    Haapasalo, M; Shen, Y; Wang, Z; Gao, Y

    2014-03-01

    Irrigation is a key part of successful root canal treatment. It has several important functions, which may vary according to the irrigant used: it reduces friction between the instrument and dentine, improves the cutting effectiveness of the files, dissolves tissue, cools the file and tooth, and furthermore, it has a washing effect and an antimicrobial/antibiofilm effect. Irrigation is also the only way to impact those areas of the root canal wall not touched by mechanical instrumentation. Sodium hypochlorite is the main irrigating solution used to dissolve organic matter and kill microbes effectively. High concentration sodium hypochlorite (NaOCl) has a better effect than 1 and 2% solutions. Ethylenediaminetetraacetic acid (EDTA) is needed as a final rinse to remove the smear layer. Sterile water or saline may be used between these two main irrigants, however, they must not be the only solutions used. The apical root canal imposes a special challenge to irrigation as the balance between safety and effectiveness is particularly important in this area. Different means of delivery are used for root canal irrigation, from traditional syringe-needle delivery to various machine-driven systems, including automatic pumps and sonic or ultrasonic energy.

  15. Lessons from the Sun

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2011-07-01

    Full Text Available In this brief note, the implications of a condensed Sun will be examined. A celestial body composed of liquid metallic hydrogen brings great promise to astronomy, relative to understanding thermal emission and solar structure. At the same time, as an incom- pressible liquid, a condensed Sun calls into question virtually everything which is cur- rently believed with respect to the evolution and nature of the stars. Should the Sun be condensed, then neutron stars and white dwarfs will fail to reach the enormous densities they are currently believed to possess. Much of cosmology also falls into question, as the incompressibility of matter curtails any thought that a primordial atom once existed. Aging stars can no longer collapse and black holes will know no formative mechanism. A condensed Sun also hints that great strides must still be made in understanding the nature of liquids. The Sun has revealed that liquids possess a much greater potential for lattice order than previously believed. In addition, lessons may be gained with regards to the synthesis of liquid metallic hydrogen and the use of condensed matter as the basis for initiating fusion on Earth.

  16. Irrigation water quality as indicator of sustainable rural development

    Directory of Open Access Journals (Sweden)

    Trajković Slaviša

    2004-01-01

    Full Text Available The sustainable rural development more and more depends on the efficient usage of water resources. Most often, at least in one part of the year, the rain is not sufficient for plant growth and rain plant production significantly depends on the yearly precipitation variation. The increase and stability of the agricultural production is possible in the irrigation conditions. The most part (around 70% of the global water resources is used for food production. Irrigation water quality indicator is used to show if the available water resources have the required quality for application in agriculture. Irrigation is characterised by the complex water-plant-soil relationship, and in that eco-system the man as the end user of the irrigated fields occupies a very important place. That explains the difficulties in producing one universal classification of irrigation water quality. The paper analyses numerous water quality classifications from the aspect of the applicability on the quantifying of this indicator. The adopted classification should possess understandable, qualified and internationally comparable indicator. Thus, local classifications (Neigebauer, Miljkovic cannot be used for this indicator. United Nation Food and Agricultural Organization (FAO and US Salinity Laboratory (USSL classifications are used for the evaluation of the irrigation water quality throughout the world. FAO classification gives the complex picture of the usability of the irrigation water from the point of its influence on the soil and the plants. However, the scope of the analyses is not often suited to the needs of that classification, which makes it difficult to apply. The conclusion is that the USSL (US Salinity Laboratory classification is best suited to this range of chemical water analyses. The evaluation of the irrigation water quality indicator in the Juzna Morava river basin, upstream from the Toplica river estuary is given in this paper. Based on the obtained

  17. A non-iterative cascaded predictive control approach for control of irrigation canals

    NARCIS (Netherlands)

    Negenborn, R.R.; Sahin, A.; Lukszo, Z.; De Schutter, B.; Morari, M.

    2009-01-01

    Irrigation canals transport water from water sources (such as large rivers and lakes) to water users (such as farmers). Irrigation canals are typically very large in nature, covering vast geographical areas, and involving a significant number of control actuators, such as pumps, gates, and locks. Th

  18. Magnetohydrodynamics of the sun

    CERN Document Server

    Priest, Eric

    2014-01-01

    Magnetohydrodynamics of the Sun is a completely new up-to-date rewrite from scratch of the 1982 book Solar Magnetohydrodynamics, taking account of enormous advances in understanding since that date. It describes the subtle and complex interaction between the Sun's plasma atmosphere and its magnetic field, which is responsible for many fascinating dynamic phenomena. Chapters cover the generation of the Sun's magnetic field by dynamo action, magnetoconvection and the nature of photospheric flux tubes such as sunspots, the heating of the outer atmosphere by waves or reconnection, the structure of prominences, the nature of eruptive instability and magnetic reconnection in solar flares and coronal mass ejections, and the acceleration of the solar wind by reconnection or wave-turbulence. It is essential reading for graduate students and researchers in solar physics and related fields of astronomy, plasma physics and fluid dynamics. Problem sets and other resources are available at www.cambridge.org/9780521854719.

  19. The Sun's Supergranulation

    CERN Document Server

    Rieutord, Michel

    2010-01-01

    The Sun's supergranulation refers to a physical pattern covering the surface of the quiet Sun with a typical horizontal scale of approximately 30000km. Its most noticeable observable signature is as a fluctuating velocity field whose components are mostly horizontal. Supergranulation was discovered more than fifty years ago, however explaining why and how it originates still represents one of the main challenges of modern solar physics. A lot of work has been devoted to the subject over the years, but observational constraints, conceptual difficulties and numerical limitations have all concurred to prevent a detailed understanding of the supergranulation phenomenon so far. With the advent of 21st century supercomputing resources and the availability of unprecedented high-resolution observations of the Sun, the solar community has now reached a stage at which key progress can be made on this question. A unifying strategy between observations and modeling is more than ever required for this to be possible. The ...

  20. Vision of irrigation

    Directory of Open Access Journals (Sweden)

    Fernando Braz-Tangerino

    2014-08-01

    Full Text Available Irrigation not only has been a key factor for the development and maintenance of human societies but it still plays this role now and it is foreseen that in the future as well. Its evolution has been constrained to the advance in knowledge on matters regarding Agronomy and Water Engineering and in technology however, many challenges deserve further research. It is worth to note that Brazil has strongly promoted irrigation in the last decade. Within the limited extension of this article, some current topics in irrigation, some of them are innovative such us the research line studying water flow in soil-plant in Mediterranean plants and its consequences on water use,. and future challenges are presented with the purpose of stimulate publication of Irrigation papers in the journal “Ingeniería del Agua” among Portuguese and Spanish language communities.

  1. Sun, Earth and Sky

    Science.gov (United States)

    Lang, Kenneth R.

    1995-01-01

    The Sun is enveloped by a hot, tenuous million-degree corona that expands to create a continuous solar wind that sweeps past all the planets and fills the heliosphere. The solar wind is modulated by strong gusts that are initiated by powerful explosions on the Sun, including solar flares and coronal mass ejections. This dynamic, invisible outer atmosphere of the Sun is currently under observation with the soft X-ray telescope aboard the Yohkoh spacecraft, whose results are presented. We also show observations from the Ulysses spacecraft that is now passing over the solar pole, sampling the solar wind in this region for the first time. Two other spacecraft, Voyager 1 and 2, have recently detected the outer edge of the invisible heliosphere, roughly halfway to the nearest star. Magnetic solar activity, the total radiative output from the Sun, and the Earth's mean global surface temperature all vary with the 11-year sunspot cycle in which the total number of sunspots varies from a maximum to a minimum and back to a maximum again in about 11 years. The terrestrial magnetic field hollows out a protective magnetic cavity, called the magnetosphere, within the solar wind. This protection is incomplete, however, so the Sun feeds an unseen world of high-speed particles and magnetic fields that encircle the Earth in space. These particles endanger spacecraft and astronauts, and also produce terrestrial aurorae. An international flotilla of spacecraft is now sampling the weak points in this magnetic defense. Similar spacecraft have also discovered a new radiation belt, in addition to the familiar Van Allen belts, except fed by interstellar ions instead of electrons and protons from the Sun.

  2. Piece of the sun

    CERN Document Server

    Wayne, Teddy

    2015-01-01

    Our rapidly industrialising world has an insatiable hunger for energy, and conventional sources are struggling to meet demand. Oil is running out, coal is damaging our climate, many nations are abandoning nuclear, yet solar, wind and water will never be a complete replacement. The solution, says Daniel Clery in this deeply researched and revelatory book, is to be found in the original energy source: the Sun itself. There, at its centre, the fusion of 630 million tonnes of hydrogen every second generates an unfathomable amount of energy. By replicating even a tiny piece of the Sun's power

  3. Near-Sun asteroids

    Science.gov (United States)

    Emel'yanenko, V. V.

    2017-01-01

    As follows from dynamical studies, in the course of evolution, most near-Earth objects reach orbits with small perihelion distances. Changes of the asteroids in the vicinity of the Sun should play a key role in forming the physical properties, size distribution, and dynamical features of the near-Earth objects. Only seven of the discovered asteroids are currently moving along orbits with perihelion distances q orbits farther from the Sun. In this study, we found asteroids that have been recently orbiting with perihelion distances q orbits for hundreds to tens of thousands of years. To carry out astrophysical observations of such objects is a high priority.

  4. The SUN S TRAVELS

    Institute of Scientific and Technical Information of China (English)

    Robert; Louis; Stevenson

    2005-01-01

    The sun is not a-bed, when I At night upon my pillow lie; Stilt round the earth his Way he takes, And morning after morning makes. White here at home, in shining day, We round the sunny garden play, Each tittle Indian sleepy - head Is being kissed and put to bed. And When at eve I rise from tea, Day dawns beyond the Atlantic Sea; And all the children in the West Are getting up and being dressed.The SUN'S TRAVELS@Robert Louis Stevenson

  5. Application of the Viterbi Algorithm in Hidden Markov Models for Exploring Irrigation Decision Series

    Science.gov (United States)

    Andriyas, S.; McKee, M.

    2014-12-01

    Anticipating farmers' irrigation decisions can provide the possibility of improving the efficiency of canal operations in on-demand irrigation systems. Although multiple factors are considered during irrigation decision making, for any given farmer there might be one factor playing a major role. Identification of that biophysical factor which led to a farmer deciding to irrigate is difficult because of high variability of those factors during the growing season. Analysis of the irrigation decisions of a group of farmers for a single crop can help to simplify the problem. We developed a hidden Markov model (HMM) to analyze irrigation decisions and explore the factor and level at which the majority of farmers decide to irrigate. The model requires observed variables as inputs and the hidden states. The chosen model inputs were relatively easily measured, or estimated, biophysical data, including such factors (i.e., those variables which are believed to affect irrigation decision-making) as cumulative evapotranspiration, soil moisture depletion, soil stress coefficient, and canal flows. Irrigation decision series were the hidden states for the model. The data for the work comes from the Canal B region of the Lower Sevier River Basin, near Delta, Utah. The main crops of the region are alfalfa, barley, and corn. A portion of the data was used to build and test the model capability to explore that factor and the level at which the farmer takes the decision to irrigate for future irrigation events. Both group and individual level behavior can be studied using HMMs. The study showed that the farmers cannot be classified into certain classes based on their irrigation decisions, but vary in their behavior from irrigation-to-irrigation across all years and crops. HMMs can be used to analyze what factor and, subsequently, what level of that factor on which the farmer most likely based the irrigation decision. The study shows that the HMM is a capable tool to study a process

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

    Science.gov (United States)

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

    2016-01-15

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

  7. Advances in Irrigation

    Science.gov (United States)

    Gardner, W. R.

    This is the first volume of Advances in Irrigation, a new serial publication by the publishers of Advances in Agronomy and Advances in Hydroscience and designed to follow the same format. The editor is a well-known researcher and writer on irrigation and related subjects and has assembled a collection of highly regarded and respected authors for the initial volume. The readership for this volume will probably be mainly specialists and students interested in irrigation and an occasional design engineer.The seven contributions in this volume fall roughly into two classes: research and practice. Three papers (“Conjunctive Use of Rainfall and Irrigation in Semi-arid Regions,” by Stewart and Musik, “Irrigation Scheduling Using Soil Moisture Measurements: Theory and Practice,” by G. S. and M. D. Campbell, and “Use of Solute Transport Models to Estimate Salt Balance Below Irrigated Cropland,” by Jury) cover topics that have been the subject of a number of reviews. The contributions here provide brief, well-written, and authoritative summaries of the chosen topics and serve as good introductions or reviews. They should lend themselves well to classroom use in various ways. They also should be helpful to the nonspecialist interested in getting a sense of the subject without going into great detail.

  8. Economic risk assessment of drought impacts on irrigated agriculture

    Science.gov (United States)

    Lopez-Nicolas, A.; Pulido-Velazquez, M.; Macian-Sorribes, H.

    2017-07-01

    In this paper we present an innovative framework for an economic risk analysis of drought impacts on irrigated agriculture. It consists on the integration of three components: stochastic time series modelling for prediction of inflows and future reservoir storages at the beginning of the irrigation season; statistical regression for the evaluation of water deliveries based on projected inflows and storages; and econometric modelling for economic assessment of the production value of agriculture based on irrigation water deliveries and crop prices. Therefore, the effect of the price volatility can be isolated from the losses due to water scarcity in the assessment of the drought impacts. Monte Carlo simulations are applied to generate probability functions of inflows, which are translated into probabilities of storages, deliveries, and finally, production value of agriculture. The framework also allows the assessment of the value of mitigation measures as reduction of economic losses during droughts. The approach was applied to the Jucar river basin, a complex system affected by multiannual severe droughts, with irrigated agriculture as the main consumptive demand. Probability distributions of deliveries and production value were obtained for each irrigation season. In the majority of the irrigation districts, drought causes a significant economic impact. The increase of crop prices can partially offset the losses from the reduction of production due to water scarcity in some districts. Emergency wells contribute to mitigating the droughts' impacts on the Jucar river system.

  9. Maximising the sun

    CSIR Research Space (South Africa)

    Conradie, Dirk CU

    2010-08-01

    Full Text Available South Africa is blessed with some of the best quality solar radiation in the world. In the light of this many exciting opportunities exist to utilize the sun to its full potential in the design of energy efficient buildings. Passive solar buildings...

  10. Sun Ultra 5

    CERN Multimedia

    1998-01-01

    The Sun Ultra 5 is a 64-bit personal computer based on the UltraSPARC microprocessor line at a low price. The Ultra 5 has been declined in several variants: thus, some models have a processor with less cache memory to further decrease the price of the computer.

  11. The Toboggan Sun

    NARCIS (Netherlands)

    Davidson, WPS; van der Werf, SY

    2005-01-01

    Special variants of the Novaya Zemlya effect may arise from localized temperature inversions that follow the height profile of hills or mountains. Rather than following its natural path, the rising or setting Sun may, under such circumstances, appear to slide along a distant mountain slope. We found

  12. Go Sun Smart

    Science.gov (United States)

    Scott, Michael D.; Buller, David B.; Walkosz, Barbara J.; Andersen, Peter A.; Cutter, Gary R.; Dignan, Mark B.

    2008-01-01

    This is the story of Go Sun Smart, a worksite wellness program endorsed by the North American Ski Area Association and funded by the National Cancer Institute. Between 2000 and 2002 we designed and implemented a large-scale worksite intervention at over 300 ski resorts in North America with the objective of reducing ski area employees and guests…

  13. Sun, Earth and Sky

    CERN Document Server

    Lang, Kenneth R

    2006-01-01

    This Second Edition of Sun, Earth and Sky updates the popular text by providing comprehensive accounts of the most recent discoveries made by five modern solar spacecraft during the past decade. Their instruments have used sound waves to peer deep into the Sun’s inner regions and measure the temperature of its central nuclear reactor, and extended our gaze far from the visible Sun to record energetic outbursts that threaten Earth. Breakthrough observations with the underground Sudbury Neutrino Observatory are also included, which explain the new physics of ghostly neutrinos and solve the problematic mismatch between the predicted and observed amounts of solar neutrinos. This new edition of Sun, Earth and Sky also describes our recent understanding of how the Sun’s outer atmosphere is heated to a million degrees, and just where the Sun’s continuous winds come from. As humans we are more intimately linked with our life-sustaining Sun than with any other astronomical object, and the new edition therefore p...

  14. Our Explosive Sun

    Science.gov (United States)

    Brown, D. S.

    2009-01-01

    The Sun's atmosphere is a highly structured but dynamic place, dominated by the solar magnetic field. Hot charged gas (plasma) is trapped on lines of magnetic force that can snap like an elastic band, propelling giant clouds of material out into space. A range of ground-based and space-based solar telescopes observe these eruptions, particularly…

  15. 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.

  16. Non-sustainable groundwater sustaining irrigation - a global assessment

    Science.gov (United States)

    Wada, Y.; van Beek, L. P. H.; Bierkens, M. F. P.

    2012-04-01

    Irrigated crops play a vital role in securing global food production. It is estimated that 17% of agricultural lands are irrigated, yet they account for 40% of the global food production, sustaining the livelihood of billions of people (Abdullah, 2006). At the same time, water used by irrigated crops (i.e., crop water demand) and irrigation water demand are responsible for about 70% of the global water withdrawal and account for about 90% of the global water consumption, i.e. water withdrawal minus return flow respectively. Water demand for irrigated crops can be met by three different sources: 1) green water, being water from local precipitation that is temporarily stored in the soil, 2) blue water, being surface freshwater available in rivers, lakes, reservoirs and wetlands, and renewable groundwater, and 3) non-renewable or non-sustainable groundwater and non-local water resources. Here, we quantify globally the amount of non-renewable groundwater abstraction to sustain current irrigation practice. We use the global hydrological model PCR-GLOBWB to simulate gross crop water demand for irrigated crops and available blue and green water to meet this demand. We downscale country statistics of groundwater abstraction by considering the part of net total water demand that cannot be met by surface freshwater. We subsequently confront these with simulated groundwater recharge including return flow from irrigation to estimate non-renewable groundwater abstraction. Results show that non-renewable groundwater abstraction contributes approximately 20% to the global gross irrigation water demand for the year 2000. The contribution of non-renewable groundwater abstraction to irrigation is largest in India (68 km3 yr-1) followed by Pakistan (35 km3/yr), USA (30 km3/yr), Iran (20 km3/yr), China (20 km3/yr), Mexico (10 km3/yr) and Saudi Arabia (10 km3/yr). Results also show that globally this contribution more than tripled from 75 to 234 km3/yr over the period 1960-2000. These

  17. Participatory rural appraisal of spate irrigation systems in eastern Eritrea

    NARCIS (Netherlands)

    Tesfai, M.; Graaff, de J.

    2000-01-01

    In the Sheeb area in eastern Eritrea a Participatory Rural Appraisal (PRA) was carried out in two villages, one upstream and one downstream of the ephemeral rivers Laba and Mai-ule. The objectives of the study were to obtain a better understanding of farmer-managed spate irrigation systems and to

  18. Participatory rural appraisal of spate irrigation systems in eastern Eritrea

    NARCIS (Netherlands)

    Tesfai, M.; Graaff, de J.

    2000-01-01

    In the Sheeb area in eastern Eritrea a Participatory Rural Appraisal (PRA) was carried out in two villages, one upstream and one downstream of the ephemeral rivers Laba and Mai-ule. The objectives of the study were to obtain a better understanding of farmer-managed spate irrigation systems and to en

  19. Stars resembling the Sun

    Science.gov (United States)

    Cayrel de Strobel, G.

    This review is primarily directed to the question whether photometric solar analogues remain such when subjected to detailed spectroscopic analyses and interpreted with the help of internal stucture models. In other words, whether the physical parameters: mass, chemical composition, age (determining effective temperature and luminosity), chromospheric activity, equatorial rotation, lithium abundance, velocity fields etc., we derive from the spectral analysis of a photometric solar analogue, are really close to those of the Sun. We start from 109 photometric solar analogues extracted from different authors. The stars selected had to satisfy three conditions: i) their colour index (B-V) must be contained in the interval: Δ (B-V) = 0.59-0.69, ii) they must possess a trigonometric parallax, iii) they must have undergone a high resolution detailed spectroscopic analysis. First, this review presents photometric and spectrophotometric researches on solar analogues and recalls the pionneering work on these stars by the late Johannes Hardorp. After a brief discussion on low and high resolution spectroscopic researches, a comparison is made between effective temperatures as obtained, directly, from detailed spectral analyses and those obtained, indirectly, from different photometric relations. An interesting point in this review is the discussion on the tantalilizing value of the (B-V)solar of the Sun, and the presentation of a new reliable value of this index. A short restatement of the kinematic properties of the sample of solar analogues is also made. And, finally, the observational ( T eff, M bol) diagram, obtained with 99 of the initially presented 109 analogues, is compared to a theoretical ( T eff, M bol) diagram. This latter has been constructed with a grid of internal structure models for which, (very important for this investigation), the Sun was used as gauge. In analysing the position, with respect to the Sun, of each star we hoped to find a certain number of

  20. A global dataset of the extent of irrigated land from 1900 to 2005

    Directory of Open Access Journals (Sweden)

    S. Siebert

    2014-12-01

    Full Text Available Irrigation intensifies land use by increasing crop yield but also impacts water resources. It affects water and energy balances and consequently the microclimate in irrigated regions. Therefore, knowledge of the extent of irrigated land is important for hydrological and crop modelling, global change research, and assessments of resource use and management. Information on the historical evolution of irrigated lands is limited. The new global Historical Irrigation Dataset (HID provides estimates of the temporal development of the area equipped for irrigation (AEI between 1900 and 2005 at 5 arc-minute resolution. We collected subnational irrigation statistics from various sources and found that the global extent of AEI increased from 63 million ha (Mha in 1900 to 112 Mha in 1950 and 306 Mha in 2005. We developed eight gridded versions of time series of AEI by combining subnational irrigation statistics with different data sets on the historical extent of cropland and pasture. Different rules were applied to maximize consistency of the gridded products to subnational irrigation statistics or to historical cropland and pasture data sets. The HID reflects very well the spatial patterns of irrigated land in the western United States as shown on historical maps. Mean aridity on irrigated land increased and river discharge decreased from 1900–1950 whereas aridity decreased from 1950–2005. The dataset and its documentation are made available in an open data repository at https://mygeohub.org/publications/8 (doi:10.13019/M2MW2G.

  1. Production Technical Rule of Alfalfa under Sprinkler Irrigation on the Thin and Arenaceous Soil at Ili River Basin in Xinjiang%新疆伊犁河流域砂质薄土层苜蓿喷灌生产技术规程

    Institute of Scientific and Technical Information of China (English)

    丁峰; 秦巧; 蒲胜海; 冯广平; 杨培林; 段生莲; 马雪琴

    2012-01-01

    为了规范新疆伊犁河流域砂质薄土层苜蓿的生产,针对伊犁河流域水土开发区域面临砂质薄土层的灌溉问题和苜蓿生产中存在的问题,依据国家及行业标准,对新疆伊犁河流域砂质薄土层新垦耕地的喷灌苜蓿种植的灌溉生产管理等提出了具体要求.针对新疆伊犁河流域砂质薄土层新垦耕地特殊的地理气候条件,对其苜蓿生产中的品种选择、培肥地力、平整土地、灌溉管理和配套栽培措施等进行了具体规定.该生产技术规程的实施对新疆伊犁河流域砂质薄土层新垦耕地苜蓿喷灌生产具有重要的现实指导意义,将显著提高饲草产量,增加农民收入,促进新疆伊犁州畜牧业的可持续发展和农村经济的快速发展.%In order to regulate the production of alfalfa on thin and arenaceous soil which was newly cultivated at Ili River basin in Xinjiang, a technical rule was presented based on national and industry standard, and the problems in irrigation question and alfalfa production on thin and arenaceous soil at Hi River basin. The technical rule was against the specific geological and climate conditions of the newly cultivated land on thin and arenaceous soil at Ili River basin in Xinjiang. It concluded variety selection, fertilization ability, land levelling, irrigation management and relevant cultivation measures. This production technical rule could be a reference to alfalfa production with sprinkler irrigation on the thin and arenaceous soil at Hi River basin in Xinjiang. With its implementation the yield of forage grass and fanner's income might be largely increased and it might promote sustainable development of animal husbandry and rural economy in Xinjiang.

  2. Phosphorus losses in furrow irrigation runoff.

    Science.gov (United States)

    Westermann, D T; Bjorneberg, D L; Aase, J K; Robbins, C W

    2001-01-01

    Phosphorus (P) often limits the eutrophication of streams, rivers, and lakes receiving surface runoff. We evaluated the relationships among selected soil P availability indices and runoff P fractions where manure, whey, or commercial fertilizer applications had previously established a range of soil P availabilities on a Portneuf silt loam (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) surface-irrigated with Snake River water. Water-soluble P, Olsen P (inorganic and organic P), and iron-oxide impregnated paper-extractable P (FeO-Ps) were determined on a 0.03-m soil sample taken from the bottom of each furrow before each irrigation in fall 1998 and spring 1999. Dissolved reactive phosphorus (DRP) in a 0.45-microm filtered runoff sample, and iron-oxide impregnated paper-extractable P (FeO-Pw), total P, and sediment in an unfiltered runoff sample were determined at selected intervals during a 4-h irrigation on 18.3-m field plots. The 1998 and 1999 data sets were combined because there were no significant differences. Flow-weighted average runoff DRP and FeO-Pw concentrations increased linearly as all three soil P test concentrations increased. The average runoff total P concentration was not related to any soil P test but was linearly related to sediment concentration. Stepwise regression selected the independent variables of sediment, soil lime concentration, and soil organic P extracted by the Olsen method as related to average runoff total P concentration. The average runoff total P concentration was 1.08 mg L(-1) at a soil Olsen P concentration of 10 mg kg(-1). Soil erosion control will be necessary to reduce P losses in surface irrigation runoff.

  3. [Waterborne iron migration by groundwater irrigation pumping in a typical irrigation district of Sanjiang Plain].

    Science.gov (United States)

    Zou, Yuan-Chun; Yu, Xiao-Fei; Huo, Li-Li; Lü, Xian-Guo; Jiang, Ming

    2012-04-01

    The iron concentration in groundwater, iron's seasonal migration from groundwater to sun-basked pools, paddy fields and drainage canals, and its distribution in the sediments/soils were observed in the Jiansanjiang Branch Bureau, Heilongjiang Agricultural Cultivation Bureau. The results suggested that the total iron mass concentration of the studied area was (1.73 +/- 0.41) mg x L(-1), ranging from 0.01 to 11.4 mg x L(-1), with the variation coefficient of 1.29%. The annual iron input mass from groundwater to paddy fields and other surface water bodies was 4 976.40 t in 2010, according to the rice planting area and rating irrigation volume. Dissolved Fe2+, Fe3+ and iron, as well as the total iron (dissolved and particle) had seasonal variation, with greater values presented in June and July. These waterborne irons in paddy field waters were greater than those in sun-basked pools and drainage canals. Obvious enrichment effect was observed in sun-basked pools and paddy fields, with their total iron mass concentrations were 6.17 and 21.65 times greater than that in groundwater. Either the total iron or iron oxides in sun-baked pool sediments were greater than that in paddy field soils, field canal and main canal sediments. The differences of the total iron and iron oxides in paddy field soils, field canal and main canal sediments were not significantly different. Considerable irons were precipitated within sun-basked pools and paddy fields during the transfer from groundwater to surface water, with a part of irons exporting into canals through drainage and then precipitated there. Not only the change of total iron mass, but the transformation of iron chemical speciation was observed during the transfer, which was affected by paddy irrigation management directly. The long-term irrigation pumping could cause the substantial enrichment of iron in paddy soils and canal sediments, resulting in the increase of potential pollution risk.

  4. SCIENCE OF SUN PHOTOMETRY

    Directory of Open Access Journals (Sweden)

    Alexandru Dan Toma

    2013-07-01

    Full Text Available Typically, the total amount of gases and particles in a column of atmosphere cannot be determined from measurements just at Earth's surface, by a single measurement essentially at the bottom of the atmosphere column. Balloons, airplanes, and rockets are all used to perform direct measurements in the atmosphere at altitudes up to and beyond the stratosphere. Satellite-based instruments provide global views, but it is difficult to infer surface and column distributions from space-based measurements, so such measurements must still be supplemented by ground-based measurements. Sun photometry is an important way of probing the atmosphere from the ground to measure the effects of the atmosphere on Sun radiation crossing through the atmosphere to Earth's surface. These indirect technique provide information about the entire atmosphere above the observer, not just the atmosphere that can be sampled directly close to Earth's surface.

  5. How hot is the sun

    Institute of Scientific and Technical Information of China (English)

    刘超

    2001-01-01

    Do you know how hot thesun is? There are no solidsor liquids on the sun. Why not? The temperature onoutside the sun is more than 10, 000℃, and that at the centre is about 20, 000, 000℃.The sun is so hot that all thesolids and all the liquids havebeen turned into gases.

  6. The sun, our star

    Science.gov (United States)

    Noyes, R. W.

    Observational data, analytical models, and instrumentation used to study the sun and its evolution are detailed, and attention is given to techniques for converting solar energy to useful power on earth. The star ignited when the mutual gravitational attractions of dust and vapor in a primordial cloud in the Galaxy caused an in-rush of accelerating particles which eventually became dense enough to ignite. The heat grew until inward rushing matter was balanced by outward moving radiative forces. The planets formed from similar debris, and solar radiation is suggested to have triggered the chemical reactions giving rise to life on earth. Visual, spectroscopic, coronagraphic, and UV observations of the sun from the ground and from spacecraft, particularly Skylab, are described, together with features of the solar surface, magnetic field, sunspots, and coronal loops. Models for the processes that occur in the solar interior are explored, as are the causes of solar flares. Attention is given to solar cells, heliostat arrays, wind turbines, and water turbines as means to convert, either directly or indirectly, the earth-bound solar energy to electrical and thermal power. Finally, the life cycle of the sun, about 9 billion yr in duration, is summarized, noting the current status of midlife.

  7. SEDIMENT CONTROL FOR IRRIGATION INTAKES

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The analysis of the sediment problems in irrigation engineeringwas carried out, and the layout, the method as well as the effect of sediment control for irrigation intake structures in China were briefly introduced.

  8. The Wichita Valley irrigation project: Joseph Kemp, boosterism, and conservation in northwest Texas, 1886-1939.

    Science.gov (United States)

    Anderson, Jahue

    2011-01-01

    This is the story of failure: in this case, an irrigation project that never met its boosters' expectations. Between 1880 and 1930, Wichita Falls entrepreneur Joseph Kemp dreamed of an agrarian Eden on the Texas rolling plains. Kemp promoted reclamation and conservation and envisioned the Big Wichita River Valley as the "Irrigated Valley." But the process of bringing dams and irrigation ditches to the Big Wichita River ignored knowledge of the river and local environment, which ultimately was key to making these complex systems work. The boosters faced serious ecological limitations and political obstacles in their efforts to conquer water, accomplishing only parts of the grandiose vision. Ultimately, salty waters and poor drainage doomed the project. While the livestock industry survived and the oil business thrived in the subsequent decades, the dream of idyllic irrigated farmsteads slowly disappeared.

  9. Planning for an Irrigation System.

    Science.gov (United States)

    Turner, J. Howard; Anderson, Carl L.

    The publication, with the aid of tables and colored illustrations and diagrams, presents information to help the farmer who is considering the installation of an irrigation system determine whether or not to irrigate, the type of system to use, and the irrigation cost and return on investment. Information is presented on the increase in yield to…

  10. Planning for an Irrigation System.

    Science.gov (United States)

    Turner, J. Howard; Anderson, Carl L.

    The publication, with the aid of tables and colored illustrations and diagrams, presents information to help the farmer who is considering the installation of an irrigation system determine whether or not to irrigate, the type of system to use, and the irrigation cost and return on investment. Information is presented on the increase in yield to…

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

    Directory of Open Access Journals (Sweden)

    Hussein M. Al-Ghobari

    2016-12-01

    Full Text Available 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.

  12. Review on Trickle Irrigation Application in Groundwater Irrigation Schemes

    Directory of Open Access Journals (Sweden)

    Prastowo

    2006-04-01

    Full Text Available The Government of Indonesia has developed groundwater irrigation schemes in some province e.g. East Java, Central Java, Yogyakarta, Wast Java, Bali, West Nusa Tenggara and East Nusa Tenggara. However, not all regions were able to optimally utilize it. The irrigation effeciency of groundwater irrigation scheme was about 59%, while the wells-pumping efficiencies were varied from 28 to 98 %. In thefuture, the irrigation effieciency should be increased to anticipate water deficit during dry season. The application of trickle irrigation in indonesia has not been widely developed. Although trickle system has been used, however, it is still limited for few commercial agribusinesses. Trickle irrigation systems have a prospect to be developed in some regions having limited water resources. For preliminary stage, the systems could be applied in groundwater irrigation schemes that have been developed either by farmers or government.

  13. Root canal irrigation

    NARCIS (Netherlands)

    L. van der Sluis; C. Boutsioukis; L.M. Jiang; R. Macedo; B. Verhaagen; M. Versluis

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  14. Studies of mineralization in South African rivers

    CSIR Research Space (South Africa)

    Hall, GC

    1978-03-01

    Full Text Available Several South African rivers are polluted by mineral salts of diffuse source. This pollution can be related to geological phenomena and to irrigation practices. Mineralization is problematic in that it can render surface waters unsuitable...

  15. Climatic effects of irrigation over the Huang-Huai-Hai Plain in China simulated by the weather research and forecasting model: Simulated Irrigation Effects in China

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ben [CMA-NJU Joint Laboratory for Climate Prediction Studies, Institute for Climate and Global Change Research, School of Atmospheric Sciences, Nanjing China; Collaborative Innovation Center of Climate Change, Jiangsu Province China; Zhang, Yaocun [CMA-NJU Joint Laboratory for Climate Prediction Studies, Institute for Climate and Global Change Research, School of Atmospheric Sciences, Nanjing China; Collaborative Innovation Center of Climate Change, Jiangsu Province China; Qian, Yun [Pacific Northwest National Laboratory, Richland Washington USA; Tang, Jian [China Meteorological Administration, Beijing China; Liu, Dongqing [Nanjing Meteorological Bureau, Nanjing China

    2016-03-14

    In this study, we apply the Weather Research and Forecasting model coupled with an operational-like irrigation scheme to investigate the climatic effects of irrigation over the Huang-Huai-Hai plain (3HP) in China. Multiple numerical experiments with irrigation off/on during spring, summer and both spring and summer are conducted, respectively. Our results show that the warm bias in surface temperature and dry bias in soil moisture are reduced over the 3HP region during growing seasons when irrigation is turned on in the model. Air temperature during non-growing seasons is also affected by irrigation due to the persistent effects of soil moisture on land-air energy exchanges and ground heat storage. Irrigation can induce a cooler planetary boundary layer (PBL) during growing seasons, causing a wetter PBL with more low-level clouds during spring but relatively dryer PBL in summer. Further analyses indicate that the dryer summer is highly related to the changes in the East Asian summer monsoon (EASM) circulation that is modified by irrigation effect. Spring irrigation may induce a decreased land-ocean thermal contrast, leading to a possible weaker EASM. Summer irrigation, however, evidently cools the atmosphere column and forces a southward shift of the upper-level jet, which results in more precipitation in Yangtze River basin but less over southern and northern China during summer.

  16. Environmental flow deficit at global scale - implication on irrigated agriculture

    Science.gov (United States)

    Pastor, Amandine; Ludwig, Fulco; Biemans, Hester; Kabat, Pavel

    2016-04-01

    Freshwater species belong to the most degraded ecosystem on earth. At the beginning of the 21st century, scientists have developed the concept of environmental flow requirements (Brisbane declaration 2003) with the aim of protecting freshwater species in the long term. However, the ecological state of rivers is different across the world depending on their fragmentation, on the presence of dams and reservoirs and on the degree of pollution. To implement new regulations on river flow, it is necessary to evaluate the degree of alteration of rivers which we called "environmental flow deficit". The European water framework directive is still working on evaluating the ecological states of river across Europe. In this study, we calculated monthly environmental flow deficit with the global vegetation dynamic and hydrological model LPJml. Environmental flow requirements were first calculated with the Variable Monthly Flow method (Pastor et al., 2014). Then, we checked in each river basin where and when the actual flow (flow minus abstraction for irrigation) does not satisfy environmental flow requirements. We finally show examples of different river basins such as the Nile and the Amazon to show how climate and irrigation can impact river flow and harm freshwater ecosystems.

  17. Review - The Sun Rises

    Directory of Open Access Journals (Sweden)

    Mark Bender

    2012-12-01

    Full Text Available Review of: Blackburn, Stuart H. 2010. The Sun Rises: A Shaman's Chant, Ritual Exchange and Fertility in the Apatani Valley. Leiden: Brill. xvii+401. Color and black and white photographs, maps. ISBN: 9789-0041-7578-5 (hardcover, 97USD. The Sun Rises is a model study contextualizing an oral narrative tradition in the social and ritual fabric of a remote community in northeast India. In many ways a companion volume to Himalayan Tribal Tales (Blackburn 2008, the text presents the first substantial translation of a key ritual text of the Apantani Valley dwellers in Arunachal Pradesh, located on the contested border between China (Tibet and India. The Apatani speak a Tibeto-Burman language, practice intensive rice agriculture in carefully terraced fields, and number about 35,000. Their clans populate several centuries-old villages. Until recently, they were separated from the lowlands of Assam and surrounded only by peoples practicing various forms of shifting agriculture. The valley dwellers have increasingly encountered modernization over the last few decades, including Indian and global popular culture, and Christianity. The heart of this book is a chant of nineteen segments.

  18. 气候变化下长江中下游水稻灌溉需水量时空变化特征%Spatiotemporal variations of rice irrigation water requirements in the mid-lower reaches of Yangtze River under changing climate

    Institute of Scientific and Technical Information of China (English)

    王卫光; 彭世彰; 孙风朝; 邢万秋; 罗玉峰; 徐俊增

    2012-01-01

    选择长江中下游单季中稻为研究对象,结合45个气象站1961~2010年逐日气象资料,基于统计降尺度模型(SDSM),生成HadCM3气候模式A2和B2两种情景下各站点参考作物腾发量和降水数据.基于联合国粮食及农业组织(FAO)推荐的作物系数法,并考虑有效性降雨和不同地区深层渗漏量,分析历史和未来的水稻灌溉需水时空变化特征.结果表明:过去50年,除了太湖流域以外的长江中下游大部分区域的参考作物腾发量和水稻需水量都呈显著下降趋势,而显著下降的水稻灌溉需水量主要位于鄱阳湖流域;未来两种情景下,参考作物腾发量、水稻需水量和水稻灌溉需水量均值都呈下降趋势,但水稻灌溉需水量降幅最小;水稻需水量和水稻灌溉需水量在长江中下游地区的变化趋势具有明显的空间异质性,水稻需水量大幅减少的区域由太湖流域向汉江和洞庭湖流域扩展.未来水稻灌溉需水量减少的区域主要分布在太湖流域、汉江流域东部和洞庭湖流域北部,并随时间推移呈扩大趋势.%Projections of rice irrigation water requirements under future climate conditions can be beneficial in developing adaptation strategies for reducing the negative impact of climate change on rice productions and to ensuring the food security from the perspective of the sustainable use of water resources. Using a statistical downscaling model (SDSM) , the projected daily reference evapotranspiration and precipitation of HadCM3 under A2 and B2 scenarios were downscaled to 45 local meteorological stations in the Mid-Lower Reaches of Yangtze River. Spatiotemporal variations of irrigation water requirements during the middle-season rice growing period for the past five decades (1961 -2010) and future dates (2011 -2099) were analyzed. The FAO (Food and Agricultural Organization) crop coefficient method and a water balance model considering the effective precipitation and

  19. Diagnóstico de la fertilidad de los suelos y estimativos sobre las necesidades de fertilizantes para el distrito de riego del Río Zulia (Norte de Santander Fertility diagnosis and fertilizer estimates for the soils of the Zulia River Irrigation District (Norte de Santander

    Directory of Open Access Journals (Sweden)

    Sánchez Ortega Gloria Patricia

    1996-12-01

    Full Text Available Entre los semestres 1994 B y 1995 A, se realizó un diagnóstico de las principales características químicas de los suelos arroceros del Distrito de Riego del Río Zulia (Norte de Santander, con el fin de identificar las principales limitantes nutricionales y definir parámetros sobre el manejo adecuado de fertilizantes y correctivos. EI uso de levantamiento de suelos preexistente, al igual que los análisis mineralógicos, foliares y de calidad de aguas para riego, en asocio con la encuesta realizada a los agricultores, permitieron una mayor precisión en el muestreo, la interpretación de los resultados y las recomendaciones finales.A diagnosis of the main chemical characteristics of the rice-growing soils of the Zulia river irrigation district (Norte de Santander was made between the semesters 19948 and 1995A, aimed at identifying the main nutritional constraints, and defining some parameters on the adequate managements of fertilizers and amendments. The use of the pre-existing soil mapping, as well as mineralogical, leaf and irrigation-water quality analyses, associated with a poll carried out among the farmers, allowed for a greater sample-precision, better interpretation of the results, and more accurate final recomendations.

  20. Eruptions from the Sun

    Science.gov (United States)

    Kohler, Susanna

    2015-11-01

    The Sun often exhibits outbursts, launching material from its surface in powerful releases of energy. Recent analysis of such an outburst captured on video by several Sun-monitoring spacecraft may help us understand the mechanisms that launch these eruptions.Many OutburstsSolar jets are elongated, transient structures that are thought to regularly release magnetic energy from the Sun, contributing to coronal heating and solar wind acceleration. Coronal mass ejections (CMEs), on the other hand, are enormous blob-like explosions, violently ejecting energy and mass from the Sun at incredible speeds.But could these two types of events actually be related? According to a team of scientists at the University of Science and Technology of China, they may well be. The team, led by Jiajia Liu, has analyzed observations of a coronal jet that they believe prompted the launch of a powerful CME.Observing an ExplosionGif of a movie of the CME, taken by the Solar Dynamics Observatorys Atmospheric Imaging Assembly at a wavelength of 304. The original movie can be found in the article. [Liu et al.]An army of spacecraft was on hand to witness the event on 15 Jan 2013 including the Solar Dynamics Observatory (SDO), the Solar and Heliospheric Observatory (SOHO), and the Solar Terrestrial Relations Observatory (STEREO). The instruments on board these observatories captured the drama on the northern limb of the Sun as, at 19:32 UT, a coronal jet formed. Just eight minutes later, a powerful CME was released from the same active region.The fact that the jet and CME occurred in the same place at roughly the same time suggests theyre related. But did the initial motions of the CME blob trigger the jet? Or did the jet trigger the CME?Tying It All TogetherIn a recently published study, Liu and collaborators analyzed the multi-wavelength observations of this event to find the heights and positions of the jet and CME. From this analysis, they determined that the coronal jet triggered the release

  1. Simulation of Irrigation Water Loss Based on VSMB Model

    Institute of Scientific and Technical Information of China (English)

    Hongwen ZHOU; Luxin ZHAI; Wenxing LU; Dongxu LIU

    2016-01-01

    The low degree of development and utilization as well as the contradiction between supply and demand of water resources in Huangshui River basin are the main restricting factors of the local agricultural development. The study on the simulation of irrigation water loss based on the VSMB model has very important significance to strengthening regional water management and improving water resource utilization efficiency. Five groundwater wells were set up to carry out the farmland irrigation water infiltration and the experimental study on groundwater dynamic effect. Two soil moisture monitoring sites were set up in two typical plots of Daxia and Guanting irrigation area at the same time and TDR300 was used to monitor four kinds of deep soil moisture( 10 cm,30 cm,50 cm and 70 cm). On this basis,the VSMB model was used to study the irrigation water loss in the irrigation area of Yellow River valley of Qinghai Province,including soil moisture content,the actual evapotranspiration,infiltration,runoff,groundwater buried depth and so on. The results showed that the water consumption caused by soil evaporation and crop transpiration accounted for 46. 4% and 24. 1% of the total precipitation plus irrigation,respectively,and the leakage accounted for 30. 3% and 60. 6% of the total precipitation plus irrigation,respectively,from March 1,2013 to April 30,and from August 1 to September 30. The actual evaporation of the GT- TR1 and GT- TR2 sites in the whole year of 2013 was 632. 6 mm and 646. 9 mm,respectively,and the leakage accounted for 2. 6% and 1. 2% of the total precipitation plus irrigation,respectively. RMSE of the simulation results of the groundwater depth in Daxia irrigation area during the two periods was 92. 3 mm and 27. 7 mm,respectively. And RMSE of the simulation results of the water content of soil profile in the two monitoring sites of Guanting irrigation area was 2. 04% and 5. 81%,respectively,indicating that the simulation results were reliable.

  2. A comparison of malaria prevalence, control and management strategies in irrigated and non-irrigated areas in eastern Kenya.

    Science.gov (United States)

    Muriuki, John Muthii; Kitala, Philip; Muchemi, Gerald; Njeru, Ian; Karanja, Joan; Bett, Bernard

    2016-08-11

    This study was conducted in Bura irrigation scheme in Tana River County and the pastoral area in Ijara, Garissa County in the eastern Kenya to establish the knowledge, attitude and practices on malaria transmission, control and management, and determine malaria prevalence and the associated risk factors. A cross sectional survey design that involved 493 randomly selected people from 334 households was used between November and December 2013. All the randomly selected people were screened for malaria parasites using rapid diagnostic test (RDT)-Carestart™ malaria HRP2 (pf) kit. A questionnaire was administered to determine potential risk factors and perceptions on malaria exposure within a period of 2 months prior to the survey. Two logistic regression models were fitted to the data; one used the RDT results while the other used data from the questionnaire survey. Using RDT, the prevalence of malaria was 4.68 % (95 % CI: 1.48-7.88 %) and 0.31 % (-0.30 to 0.92 %) in irrigated and non-irrigated areas, respectively. From the questionnaires, 14.62 % (9.27-19.97 %) and 23.91 % (19.23-28.60 %) of the participants perceived to have had malaria in the irrigated and pastoral areas, respectively. The main malaria control measure was the use of bed nets: average of three nets per household in Bura irrigation scheme and one in Ijara. Artemether-lumefantrine was the main drug of choice mainly in the irrigated area while sulfadoxine-pyrimethamine was likely to be used in the non-irrigated area. Households located >5 km from the nearest health facility had higher prevalence of Plasmodium infection than those located ≤5 km. The residents of Bura irrigation scheme were more likely to be infected compared to those living in the non-irrigated area of Ijara. However, those in the non-irrigated area were more likely to be treated or use over-the-counter medication for perceived malaria illnesses compared to those in the irrigated area. There is a need, therefore, to

  3. The Dynamic Change and Trend of Groundwater Level in Jinan Yellow River Irrigation Region More Than Twenty Years%济南引黄灌区近20年地下水位动态变化及趋势分析

    Institute of Scientific and Technical Information of China (English)

    徐淑波; 徐立荣; 梅泽本

    2016-01-01

    利用多年观测资料,对济南引黄灌区地下水位动态变化特征及趋势进行了分析,结果表明:①近二十年济南引黄灌区地下水位年际变化趋势主要受引黄灌溉水量的影响,2002-2013年来地下水位波动下降明显;多年月均地下水位变化出现两个峰值,主峰值主要受汛期降水的影响,次峰值主要受春季引黄灌溉的影响。②对地下水位多年序列和季节序列进行M -K趋势和参数特征分析表明,灌区2000年以后地下水位呈下降趋势,且在2012年以后下降趋势较显著;春季和夏季地下水位总体上无明显趋势,而秋季和冬季分别在2003年和2006年以后呈现较明显的下降趋势。③由于秋季灌区引黄供水远远不能满足实际需水量,为缓解地下水位下降,应适当增加秋季引黄量。%Based on the observational data of many years ,the Mann-Kendall trend test method was adopted to analyze the dynamic change and trend of groundwater level in Jinan Yellow River Irrigation Region .The results indicate that :The trend of annual varia‐tion of groundwater level was mainly affected by irrigation water in irrigation area of Jinan in recent twenty years ,the fluctuation of groundwater level decreased significantly from 2002 to 2013 ;monthly groundwater level has two peaks ,the primary peak mainly af‐fected by the precipitation of flood season and the secondary peak by water supply from the Yellow River in spring .Mann-Kendall trend test of annual and seasonal groundwater level showed that groundwater level declined from 2000 to 2013 ,significantly after 2012 .The rising trend of groundwater level both in spring and summer is not significant ,while significant declining trend of ground‐water level in autumn and in winter can be found after 2003 and 2006 respectively .In autumn drawing groundwater leads to falling of water table as a result of inadequate water supply from the Yellow River for

  4. EVALUATION OF PHYSICO-CHEMICAL PARAMETERS OF AGRICULTURAL SOILS IRRIGATED BY THE WATERS OF THE HYDROLIC BASIN OF SEBOU RIVER AND THEIR INFLUENCES ON THE TRANSFER OF TRACE ELEMENTS INTO SUGAR CROPS (THE CASE OF SUGAR CANE

    Directory of Open Access Journals (Sweden)

    N. Benlkhoubi

    2016-05-01

    Full Text Available This research was conducted in Kenitra (northwestern Morocco to determine the physicochemical parameters and metallic concentrations at three levels: surface water of Sebou and Beht intended for irrigation, agricultural soils and sugarcane. The spectrometric analysis of source plasma emission (ICP has identified eight trace elements contained in the materials taken from zone 1 (As, Cd, Co, Zn, Ni, Pb, Cu and Cr.The obtained results showed that the interaction between the different physicochemical parameters of agricultural soils decides the transfer of the metal elements to the plants. Indeed, for the soil which is used in this agriculture (for sugar cane, its irrigation water, and the contents of Cr, Cd and As exceeds the accepted standards.The principal component analysis of the levels of trace metal supports in area 1, allowed to distinguish between the items with a high tolerance for bagasse (Zn, Cu, Ni, Cd and Pb, compared to Cr, Co, and As.

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

    Science.gov (United States)

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

    1959-01-01

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

  6. Spectrophotometric determination of irrigant extrusion using passive ultrasonic irrigation, EndoActivator, or syringe irrigation.

    Science.gov (United States)

    Rodríguez-Figueroa, Carolina; McClanahan, Scott B; Bowles, Walter R

    2014-10-01

    Sodium hypochlorite (NaOCl) irrigation is critical to endodontic success, and several new methods have been developed to improve irrigation efficacy (eg, passive ultrasonic irrigation [PUI] and EndoActivator [EA]). Using a novel spectrophotometric method, this study evaluated NaOCl irrigant extrusion during canal irrigation. One hundred fourteen single-rooted extracted teeth were decoronated to leave 15 mm of the root length for each tooth. Cleaning and shaping of the teeth were completed using standardized hand and rotary instrumentation to an apical file size #40/0.04 taper. Roots were sealed (not apex), and 54 straight roots (n = 18/group) and 60 curved roots (>20° curvature, n = 20/group) were included. Teeth were irrigated with 5.25% NaOCl by 1 of 3 methods: passive irrigation with needle, PUI, or EA irrigation. Extrusion of NaOCl was evaluated using a pH indicator and a spectrophotometer. Standard curves were prepared with known amounts of irrigant to quantify amounts in unknown samples. Irrigant extrusion was minimal with all methods, with most teeth showing no NaOCl extrusion in straight or curved roots. Minor NaOCl extrusion (1-3 μL) in straight roots or curved roots occurred in 10%-11% of teeth in all 3 irrigant methods. Two teeth in both the syringe irrigation and the EA group extruded 3-10 μL of NaOCl. The spectrophotometric method used in this study proved to be very sensitive while providing quantification of the irrigant levels extruded. Using the PUI or EA tip to within 1 mm of the working length appears to be fairly safe, but apical anatomy can vary in teeth to allow extrusion of irrigant. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Irrigation mitigates against heat extremes

    Science.gov (United States)

    Thiery, Wim; Fischer, Erich; Visser, Auke; Hirsch, Annette L.; Davin, Edouard L.; Lawrence, Dave; Hauser, Mathias; Seneviratne, Sonia I.

    2017-04-01

    Irrigation is an essential practice for sustaining global food production and many regional economies. Emerging scientific evidence indicates that irrigation substantially affects mean climate conditions in different regions of the world. Yet how this practice influences climate extremes is currently unknown. Here we use gridded observations and ensemble simulations with the Community Earth System Model to assess the impacts of irrigation on climate extremes. While the influence of irrigation on annual mean temperatures is limited, we find a large impact on temperature extremes, with a particularly strong cooling during the hottest day of the year (-0.78 K averaged over irrigated land). The strong influence on hot extremes stems from the timing of irrigation and its influence on land-atmosphere coupling strength. Together these effects result in asymmetric temperature responses, with a more pronounced cooling during hot and/or dry periods. The influence of irrigation is even more pronounced when considering subgrid-scale model output, suggesting that local effects of land management are far more important than previously thought. Finally we find that present-day irrigation is partly masking GHG-induced warming of extreme temperatures, with particularly strong effects in South Asia. Our results overall underline that irrigation substantially reduces our exposure to hot temperature extremes and highlight the need to account for irrigation in future climate projections.

  8. Asian irrigation, African rain: Remote impacts of irrigation

    Science.gov (United States)

    Vrese, Philipp; Hagemann, Stefan; Claussen, Martin

    2016-04-01

    Irrigation is not only vital for global food security but also constitutes an anthropogenic land use change, known to have strong effects on local hydrological and energy cycles. Using the Max Planck Institute for Meteorology's Earth System Model, we show that related impacts are not confined regionally but that possibly as much as 40% of the present-day precipitation in some of the arid regions in Eastern Africa are related to irrigation-based agriculture in Asia. Irrigation in South Asia also substantially influences the climate throughout Southeast Asia and China via the advection of water vapor and by altering the Asian monsoon. The simulated impact of irrigation on remote regions is sensitive to the magnitude of the irrigation-induced moisture flux. Therefore, it is likely that a future extension or decline of irrigated areas due to increasing food demand or declining fresh water resources will also affect precipitation and temperatures in remote regions.

  9. Seasonal effects of irrigation on land-atmosphere latent heat, sensible heat, and carbon fluxes in semiarid basin

    Science.gov (United States)

    Zeng, Yujin; Xie, Zhenghui; Liu, Shuang

    2017-02-01

    Irrigation, which constitutes ˜ 70 % of the total amount of freshwater consumed by the human population, is significantly impacting land-atmosphere fluxes. In this study, using the improved Community Land Model version 4.5 (CLM4.5) with an active crop model, two high-resolution (˜ 1 km) simulations investigating the effects of irrigation on latent heat (LH), sensible heat (SH), and carbon fluxes (or net ecosystem exchange, NEE) from land to atmosphere in the Heihe River basin in northwestern China were conducted using a high-quality irrigation dataset compiled from 1981 to 2013. The model output and measurements from remote sensing demonstrated the capacity of the developed models to reproduce ecological and hydrological processes. The results revealed that the effects of irrigation on LH and SH are strongest during summer, with a LH increase of ˜ 100 W m-2 and a SH decrease of ˜ 60 W m-2 over intensely irrigated areas. However, the reactions are much weaker during spring and autumn when there is much less irrigation. When the irrigation rate is below 5 mm day-1, the LH generally increases, whereas the SH decreases with growing irrigation rates. However, when the irrigation threshold is in excess of 5 mm day-1, there is no accrued effect of irrigation on the LH and SH. Irrigation produces opposite effects to the NEE during spring and summer. During the spring, irrigation yields more discharged carbon from the land to the atmosphere, increasing the NEE value by 0.4-0.8 gC m-2 day-1, while the summer irrigation favors crop fixing of carbon from atmospheric CO2, decreasing the NEE value by ˜ 0.8 gC m-2 day-1. The repercussions of irrigation on land-atmosphere fluxes are not solely linked to the irrigation amount, and other parameters (especially the temperature) also control the effects of irrigation on LH, SH, and NEE.

  10. 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.

  11. Expansion of an Existing Water Management Model for the Analysis of Opportunities and Impacts of Agricultural Irrigation under Climate Change Conditions

    Directory of Open Access Journals (Sweden)

    Jörg Steidl

    2015-11-01

    Full Text Available The impact of climate change and increased irrigation area on future hydrologic and agro-economic conditions was analysed for a representative basin in northeastern Germany using an expanded version of the WBalMO (water balance model for water management. The model expansion represents various temporally and spatially differentiated irrigation water use processes, including agricultural irrigation, as part of a river basin’s water management. We show that climate changes lead to increased irrigation water demands in the future, which will not always be able to be met. The resulting water deficits were shown for different crops depending on their irrigation priority and the water available. With an increased irrigation area, water deficits will rise. This may limit the profitability of agricultural irrigation. The impacts of climate change on low-flow conditions in the river are much higher than those of the increase in irrigated area alone. Therefore, any additional increases of irrigation will require careful monitoring of water availability to avoid critical impacts on river flows. The expanded model was able to replicate the processes of agricultural irrigation water use and can thus be used to test the impact of policies such as the certification of new irrigation permits.

  12. The validated sun exposure questionnaire

    DEFF Research Database (Denmark)

    Køster, B; Søndergaard, J; Nielsen, J B

    2017-01-01

    Few questionnaires used in monitoring sun-related behavior have been tested for validity. We established criteria validity of a developed questionnaire for monitoring population sun-related behavior. During May-August 2013, 664 Danes wore a personal electronic UV-dosimeter for one week...... that measured the outdoor time and dose of erythemal UVR exposure. In the following week, they answered a questionnaire on their sun-related behavior in the measurement week. Outdoor time measured by dosimetry correlated strongly with both outdoor time and the developed exposure scale measured....... The weekly sunburn fraction correlated strongly with the number of ambient sun hours (r=0.73, p

  13. The Sun, Mercury, and Venus

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    The Messenger mission to Mercury opened a new window into the inner solar system. In 2008, this mission began a number of years of flybys, culminating in an orbital insertion around Mercury and producing unparalleled observations about this mysterious innermost planet. Mercury orbits so close to the Sun, from the point of view of Earth, that seeing it from the Earth against the Sun's glare is a great challenge. At the same time, the huge gravitational force of the Sun makes it a challenge to put a mission on Mercury without losing it into the Sun. Now, with heightened understanding of Mercury,

  14. The Rapidly Rotating Sun

    Science.gov (United States)

    Hanasoge, Shravan M.; Duvall, Thomas L., Jr.; Sreenivasan, Katepalli R.

    2012-01-01

    Convection in the solar interior is thought to comprise structures at a continuum of scales, from large to small. This conclusion emerges from phenomenological studies and numerical simulations though neither covers the proper range of dynamical parameters of solar convection. In the present work, imaging techniques of time-distance helioseismology applied to observational data reveal no long-range order in the convective motion. We conservatively bound the associated velocity magnitudes, as a function of depth and the spherical-harmonic degree l to be 20-100 times weaker than prevailing estimates within the wavenumber band l ux of a solar luminosity outwards? The Sun is seemingly a much faster rotator than previously thought, with advection dominated by Coriolis forces at scales l < 60.

  15. Sun light European Project

    Science.gov (United States)

    Soubielle, Marie-Laure

    2015-04-01

    2015 has been declared the year of light. Sunlight plays a major role in the world. From the sunbeams that heat our planet and feed our plants to the optical analysis of the sun or the modern use of sun particles in technologies, sunlight is everywhere and it is vital. This project aims to understand better the light of the Sun in a variety of fields. The experiments are carried out by students aged 15 to 20 in order to share their discoveries with Italian students from primary and secondary schools. The experiments will also be presented to a group of Danish students visiting our school in January. All experiments are carried out in English and involve teams of teachers. This project is 3 folds: part 1: Biological project = what are the mechanisms of photosynthesis? part 2: Optical project= what are the components of sunlight and how to use it? part 3: Technical project= how to use the energy of sunlight for modern devices? Photosynthesis project Biology and English Context:Photosynthesis is a process used by plants and other organisms to convert light energy, normally from the Sun, into chemical energy that can later fuel the organisms' activities. This chemical energy is stored in molecules which are synthesized from carbon dioxide and water. In most cases, oxygen is released as a waste product. Most plants perform photosynthesis. Photosynthesis maintains atmospheric oxygen levels and supplies all of the organic compounds and most of the energy necessary for life on Earth. Outcome: Our project consists in understanding the various steps of photosynthesis. Students will shoot a DVD of the experiments presenting the equipments required, the steps of the experiments and the results they have obtained for a better understanding of photosynthesis Digital pen project Electricity, Optics and English Context: Sunlight is a complex source of light based on white light that can be decomposed to explain light radiations or colours. This light is a precious source to create

  16. Physics of the sun

    CERN Document Server

    Holzer, Thomas; Mihalas, Dimitri; Ulrich, Roger

    1986-01-01

    This volume, together with its two companion volumes, originated in a study commis­ sioned by the United States National Academy of Sciences on behalf of the National Aeronautics and Space Administration. A committee composed of Tom Holzer, Dimitri Mihalas, Roger Ulrich and myself was asked to prepare a comprehensive review of current knowledge concerning the physics of the sun. We were fortunate in being able to persuade many distinguished scientists to gather their forces for the preparation of 21 separate chapters covering not only solar physics but also relevant areas of astrophysics and solar-terrestrial relations. It proved necessary to divide the chapters into three separate volumes that cover three different aspects of solar physics. Volumes 1 and 2 are concerned with 'The Solar Interior' and with 'The Solar Atmosphere'. This volume, devoted to 'Astrophysics and Solar-Terrestrial Relations', focuses on problems of solar physics from these two different but complementary perspectives. The emphasis thr...

  17. Effect of low‐cost irrigation methods on microbial contamination of lettuce irrigated with untreated wastewater

    National Research Council Canada - National Science Library

    Keraita, Bernard; Konradsen, Flemming; Drechsel, Pay; Abaidoo, Robert C

    2007-01-01

    Objective  To assess the effectiveness of simple irrigation methods such as drip irrigation kits, furrow irrigation and use of watering cans in reducing contamination of lettuce irrigated with polluted water...

  18. 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

  19. Why the sun sucks - Architects versus the sun

    NARCIS (Netherlands)

    De Lange, N.; Niesten, J.; Taminiau, P.

    2014-01-01

    This "designers' manual" is made during the TIDO-course AR0531 Innovation and Sustainability This manual will show how not to design with the Sun. By showing examples how buildings have failed that have not taken the Sun and its effects in consideration, one should get a clearer picture of how you

  20. Why the sun sucks - Architects versus the sun

    NARCIS (Netherlands)

    De Lange, N.; Niesten, J.; Taminiau, P.

    2014-01-01

    This "designers' manual" is made during the TIDO-course AR0531 Innovation and Sustainability This manual will show how not to design with the Sun. By showing examples how buildings have failed that have not taken the Sun and its effects in consideration, one should get a clearer picture of how you

  1. Sediment transport in irrigation canals

    OpenAIRE

    Méndez V., N.J.

    1998-01-01

    The world population is rapidly increasing and is expected to double to about 10 billion by the year 2050. To support an increasing population in terms of food sufficiency, more and more water will be required. Irrigation is the most critical component of the modern package of inputs to effect high crop production. Irrigation has been the largest recipient of public agricultural investment in the developing world. Hence, continued investment in irrigation along with reforms in institutional a...

  2. Características químicas de solos da região de Janaúba, MG, irrigados com água de poços tubulares e do rio Gorutuba Chemical characteristics of soils irrigated with deep-well or Gorutuba river water in Janauba region, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Walder Antonio Gomes de Albuquerque Nunes

    2008-02-01

    Full Text Available Na região de Janaúba, norte de Minas Gerais, não obstante as altas produtividades alcançadas pela bananicultura da região no contexto de uma agricultura altamente tecnificada, com uso intenso de fertilizantes e controle sistemático de doenças e pragas, são comuns os relatos de produtores expressando preocupação com a queda de produtividade, particularmente quando se irriga com água de poços tubulares. Em razão disso, estudou-se o efeito de águas de irrigação provenientes de poços e do rio Gorutuba sobre propriedades químicas de solos sob bananais, onde foram coletadas amostras até 100 cm de profundidade em áreas adjacentes de sequeiro e irrigadas. Observou-se que o uso de águas de poços, de qualidade marginal, causou elevação do pH e dos teores de Ca2+ e Na+ dos solos, elevando as relações Ca/Mg e Ca/K, que se distanciaram da faixa ideal para a cultura da banana. Nos solos irrigados com água de poços houve aumento dos teores de P extraído com H2SO4, resultante da precipitação do P com o Ca veiculado com a água. Os valores de pH do extrato de saturação do solo foram mais elevados que aqueles registrados na análise de rotina, e a concentração de sais solúveis na solução do solo ocorreu em camadas intermediárias do perfil devido à lixiviação, com destaque para a camada de 30-40 cm dos solos irrigados com água de poços.In the region of Janaúba, northern Minas Gerais State, Brazil, banana yields are high due to the highly technical agriculture of the region, with intensive use of fertilizers and systematic plant disease and pest control. However, farmers frequently report a decline in banana yields, particularly when water from deep wells is used for irrigation. We therefore studied the effect of irrigation water from wells and from the Gorutuba River on soil chemical characteristics of areas with banana cultivation. Soil samples were collected to a depth of 100 cm in adjacent areas with and without

  3. Smart, passive sun facing surfaces

    Science.gov (United States)

    Hively, Lee M.

    1996-01-01

    An article adapted for selectively utilizing solar radiation comprises an absorptive surface and a reflective surface, the absorptive surface and the reflective surface oriented to absorb solar radiation when the sun is in a relatively low position, and to reflect solar radiation when the sun is in a relatively high position.

  4. Global Seismology of the Sun

    CERN Document Server

    Basu, Sarbani

    2016-01-01

    The seismic study of the Sun and other stars offers a unique window into the interior of these stars. Thanks to helioseismology, we know the structure of the Sun to admirable precision. In fact, our knowledge is good enough to use the Sun as a laboratory. We have also been able to study the dynamics of the Sun in great detail. Helioseismic data also allow us to probe the changes that take place in the Sun as solar activity waxes and wanes. The seismic study of stars other than the Sun is a fairly new endeavour, but we are making great strides in this field. In this review I discuss some of the techniques used in helioseismic analyses and the results obtained using those techniques. In this review I focus on results obtained with global helioseismology, i.e., the study of the Sun using its normal modes of oscillation. I also briefly touch upon asteroseismology, the seismic study of stars other than the Sun, and discuss how seismic data of others stars are interpreted.

  5. A Comment and an Analysis of the Management System of the Irrigating--water in the Arid Northwest Inland--river Area of the Early Modern Times: A Case Study of Hexi Gansu%近代西北干旱内陆河区灌溉水管理制度评析——以甘肃省河西地区为例

    Institute of Scientific and Technical Information of China (English)

    吴晓军

    2012-01-01

    In the early modern times, the social communities were founded along the river valleys and irrigating dykes in the arid northwest inland--river area. In order to solve the conflicts caused by the using water, and to manage efficiently the allocation of the water resources, the regulations of allocating water were established by the counties between the upper and the lower reaches, the management institution of the irrigating--water was set up by each county, the irrigating regulations were universally made to stipu- late the usage of the irrigating--water, and to make clear the users' rights and responsibilities. The fact not only reflects the general vicissitudes of the rural villages in the arid northwest inland--river area, but also show us that the management of the irrigating water exerts tremendous influence on the rural commu- nities in the area of fragile environment. Examining the problem from a historical perspective, the signifi- cances of it are: the key spirit of the management of the irrigating--water is fairness and impartiality, and the basic responsibility of the local government is to defend the masses' rights and interests of using wa- ter; the only way out of the conflicts caused by water supply is to provide more water and develop water resources; the development and management of irrigating--water can expand the living space of human-- being, and become the fundamental social bonds; the right to manage the irrigating-- water was monopo- lized by the gentry class combined with religious authority show clearly the limitation of the times.%近代西北干旱内陆河区形成了以流域和灌溉渠系为纽带的社会群落,为了解决用水纠纷,做好水资源的管理分配,河流上下游各县之间制定了分水制度,各县建立灌溉用水的管理机构,灌区内普遍制定了水规,规定灌溉水的使用方法,明确用户的权利与责任。其不但反映了西北干旱内陆河区农村村社变迁的

  6. Irrigation trends in Kansas, 1991–2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This fact sheet examines trends in total reported irrigation water use and acres irrigated as well as irrigation water use by crop type and system type in Kansas for...

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

    Science.gov (United States)

    Essaid, Hedeff I.; Caldwell, Rodney R.

    2017-01-01

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

  8. Reconnection on the Sun

    Science.gov (United States)

    Kohler, Susanna

    2016-05-01

    Because the Sun is so close, it makes an excellent laboratory to study processes we cant examinein distant stars. One openquestion is that of how solar magnetic fields rearrange themselves, producing the tremendous releases of energy we observe as solar flares and coronal mass ejections (CMEs).What is Magnetic Reconnection?Magnetic reconnection occurs when a magnetic field rearranges itself to move to a lower-energy state. As field lines of opposite polarity reconnect, magnetic energy is suddenly converted into thermal and kinetic energy.This processis believed to be behind the sudden releases of energy from the solar surface in the form of solar flares and CMEs. But there are many different models for how magnetic reconnection could occur in the magnetic field at the Suns surface, and we arent sure which one of these reconnection types is responsible for the events we see.Recently, however, several studies have been published presenting some of the first observational support of specific reconnection models. Taken together, these observations suggest that there are likely several different types of reconnection happening on the solar surface. Heres a closer look at two of these recent publications:A pre-eruption SDO image of a flaring region (b) looks remarkably similar to a 3D cartoon for typical breakout configuration (a). Click for a closer look! [Adapted from Chen et al. 2016]Study 1:Magnetic BreakoutLed by Yao Chen (Shandong University in China), a team of scientists has presented observations made by the Solar Dynamics Observatory (SDO) of a flare and CME event that appears to have been caused by magnetic breakout.In the magnetic breakout model, a series of loops in the Suns lower corona are confined by a surrounding larger loop structure called an arcade higher in the corona. As the lower loops push upward, reconnection occurs in the upper corona, removing the overlying, confining arcade. Without that extra confinement, the lower coronal loops expand upward

  9. Identifying regions vulnerable to habitat degradation under future irrigation scenarios

    Science.gov (United States)

    Terrado, Marta; Sabater, Sergi; Acuña, Vicenç

    2016-11-01

    The loss and degradation of natural habitats is a primary cause of biodiversity decline. The increasing impacts of climate and land use change affect water availability, ultimately decreasing agricultural production. Areas devoted to irrigation have been increased to compensate this reduction, causing habitat and biodiversity losses, especially in regions undergoing severe water stress. These effects might intensify under global change, probably contributing to a decrease in habitat quality. We selected four European river basins across a gradient of water scarcity and irrigation agriculture. The habitat quality in the basins was assessed as a function of habitat suitability and threats under current and future global change scenarios of irrigation. Results revealed that the most threatened regions under future scenarios of global change were among those suffering of water scarcity and with bigger areas devoted to irrigation. Loss of habitat quality reached 10% in terrestrial and 25% in aquatic ecosystems under climate change scenarios involving drier conditions. The aquatic habitats were the most degraded in all scenarios, since they were affected by threats from both the terrestrial and the aquatic parts of the basin. By identifying in advance the regions most vulnerable to habitat and biodiversity loss, our approach can assist decision makers in deciding the conservation actions to be prioritized for mitigation and adaptation to the effects of climate change, particularly front the development of irrigation plans.

  10. Soil Water Distribution and Irrigation Uniformity Under Alternative Furrow Irrigation

    Institute of Scientific and Technical Information of China (English)

    PAN Ying-hua; KANG Shao-zhong; DU Tai-sheng; YANG Xiu-ying

    2003-01-01

    Field experiments were conducted to investigate the spatial-temporal distribution and the uni-formity of soil water under alternative furrow irrigation in spring maize field in Gansu Province. Resultsshowed that during the crop growing season, alternative drying and wetting furrows could incur crops to en-dure a water stress, thus the adsorptive ability of root system could be enhanced. As there was no zero fluxplane between irrigated furrows and non-irrigated furrows under alternative furrow irrigation, lateral infiltra-tion of water was obviously increased, thus decreasing the deep percolation. Compared with the conventionalirrigation, although the water consumption in alternative furrow irrigation was reduced, the uniformity of soilwater was not obviously affected.

  11. Cases Studies of Irrigated Soil Degradation and Progradation

    Science.gov (United States)

    Zeyliger, Anatoly; Kust, German; Rozov, Sergey; Stoma, Galina

    2013-04-01

    Waterlogging and salination, along with interaction with other degradation processes, have not only caused the collapse of irrigation-based societies in the past, but are indeed threatening the viability of irrigation at present. The problem is global in scope. Decimation of natural ecosystems, deterioration of soil productivity depletion and pollution of water resources, and conflicts over dwindling supplies have become international problems closely linked with extension of irrigation development to large scale and associated impact to soil fertility and surrounding environment. Practical experience and scientific research done in the frame of FP6 DESIRE project provided an affirmative answer to the question - can irrigated agriculture be sustained for long time. In present contribution two case studies will be discussed and analysed in scope to compare different irrigation practises used for about 35 years and their impact to soil fertility. Investigated areas of both case studies are situated in the same Saratov Region of Russia at the left bank of middle part of Volga River with distance between about 100 km. First case study was developed during 2009-2010 by field trials at irrigated and surrounded areas of agricultural farms situated at Privolghskaya Irrigation System (Marksovsky District). Second case study was developed during summer of 2011 by field trial at experimental farm of research institute called VolgNIIGiM (Enghelsky District). During fields trail soil maps of both case studies were developed and compared with soil maps of the same areas done at 1970th before irrigation projects at both areas were started. Results of soil map comparison are showing that in the territory of first case study considerable soil degradation is taken place, but in the territory of the second case study a substantial soil progradation is taken place. Thus is supported by the time series of ground water monitoring at both irrigated areas. Obtained results will be

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

    Science.gov (United States)

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

    2014-12-01

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

  13. Totality eclipses of the Sun

    CERN Document Server

    Littmann, Mark; Willcox, Ken

    2008-01-01

    A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. - ;A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. Totality: Eclipses of the Sun is the best guide and reference book on solar eclipses ever written. It explains: how to observe them; how to photograph and videotape them; why they occur; their history and mythology; and future eclipses - when and where to see them. Totality also tells the remarkable story of how eclipses shocked scientists, revealed the workings of the Sun, and made Einstein famous. And the book shares the experiences and advice of many veteran eclipse observers. Totality: Eclipses of the Sun is profusely ill...

  14. Irrigation management in organic greenhouse

    NARCIS (Netherlands)

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

    2017-01-01

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

  15. CROP UNDER DEFICIT IRRIGATION SCHEDULING

    African Journals Online (AJOL)

    This study presents crop coefficient (Kc) values of TMV 1 -ST maize variety ... given time from planting to the time it is harvested. ... real time irrigation scheduling for high frequent and non-fiequent water .... 10 m, and the average soil bulk density was 1420 kg/m'. ...... Performance Evaluation of Fadama Irrigation Practice.

  16. Sun, UV Radiation and Your Eyes

    Science.gov (United States)

    ... Patient Stories Español Eye Health / Tips & Prevention Your Eyes and the Sun Sections The Sun, UV Radiation ... Safety Infographic The Sun, UV Radiation and Your Eyes Written by: David Turbert Aug. 28, 2014 Keep ...

  17. Clustering of Sun Exposure Measurements

    DEFF Research Database (Denmark)

    Have, Anna Szynkowiak; Larsen, Jan; Hansen, Lars Kai

    2002-01-01

    In a medically motivated Sun-exposure study, questionnaires concerning Sun-habits were collected from a number of subjects together with UV radiation measurements. This paper focuses on identifying clusters in the heterogeneous set of data for the purpose of understanding possible relations between...... Sun-habits exposure and eventually assessing the risk of skin cancer. A general probabilistic framework originally developed for text and Web mining is demonstrated to be useful for clustering of behavioral data. The framework combines principal component subspace projection with probabilistic...

  18. Prototype of sun projector device

    Science.gov (United States)

    Ihsan; Dermawan, B.

    2016-11-01

    One way to introduce astronomy to public, including students, can be handled by solar observation. The widely held device for this purpose is coelostat and heliostat. Besides using filter attached to a device such as telescope, it is safest to use indirect way for observing the Sun. The main principle of the indirect way is deflecting the sun light and projecting image of the sun on a screen. We design and build a simple and low-cost astronomical device, serving as a supplement to increase public service, especially for solar observation. Without using any digital and intricate supporting equipment, people can watch and relish image of the Sun in comfortable condition, i.e. in a sheltered or shady place. Here we describe a design and features of our prototype of the device, which still, of course, has some limitations. In the future, this prototype can be improved for more efficient and useful applications.

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

    Science.gov (United States)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2016-04-01

    results of analyzing water stress during growing season of 2012 and yielded biomass of crops three types of crops alfalfa, corn and soya irrigated by sprinkling machines at left bank of Volga River at Saratov Region of Russia are presented and analyzed. For that a combination of data received from satellite, local meteorological station and farmers as well as SWAP model was used. Analyze of data sets of monitored water deficit of each crop averaged for irrigation period was done by linear regression with yielded biomass values. Following analyze of effectiveness of irrigation water application was done by SWAP agrohydrological model.

  20. Qualidade da água subterrânea para irrigação na bacia hidrográfica do Rio Piauí, em Sergipe Groundwater quality for irrigation purposes in Piauí River Basin in the State of Sergipe, Brazil

    Directory of Open Access Journals (Sweden)

    Julio R. A. de Amorim

    2010-01-01

    . Physicochemical data of water from 278 deep wells located in Piauí River Basin, in the State of Sergipe, Brazil, were used considering the FAO restriction criteria for irrigation purposes. Maps of spatial distribution of groundwater quality indicators in the watershed were prepared by ordinary kriging procedures. Groundwaters showed good quality for irrigation use, mainly in the center-downstream portion of the river basin. There was a trend in increasing the salt concentration in water from the coast to inland in the Piauí River Basin area.

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

    Science.gov (United States)

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

    2014-03-01

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

  2. 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.

  3. Soil management and conservation: Irrigation: Methods

    Science.gov (United States)

    Irrigation applies water to soil to improve crop production. The three main methods of irrigation are surface, sprinkler and micro. Surface irrigation is used on 85% of the irrigated land in the world. It generally requires lower capital investment because the soil conveys water within the field, ra...

  4. Wireless sensor networks for irrigation management

    Science.gov (United States)

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

  5. The effect of naturally acidified irrigation water on agricultural volcanic soils. The case of Asembagus, Java, Indonesia

    NARCIS (Netherlands)

    Los, A.M.D.; Vriend, S.P.; Bergen, M.J.; Gaans, R.F.M.

    2008-01-01

    Acid water from the Banyuputih river (pH similar to 3.5) is used for the irrigation of agricultural land in the Asembagus coastal area (East Java, Indonesia), with harmful consequences for rice yields. The river water has an unusual composition which is caused by seepage from the acidic Kawah Ijen

  6. The effect of naturally acidified irrigation water on agricultural volcanic soils. The case of Asembagus, Java, Indonesia

    NARCIS (Netherlands)

    Los, A.M.D.; Vriend, S.P.; Bergen, M.J.; Gaans, R.F.M.

    2008-01-01

    Acid water from the Banyuputih river (pH similar to 3.5) is used for the irrigation of agricultural land in the Asembagus coastal area (East Java, Indonesia), with harmful consequences for rice yields. The river water has an unusual composition which is caused by seepage from the acidic Kawah Ijen c

  7. 76 FR 20971 - Turlock Irrigation District and Modesto Irrigation District; Notice of Intent To File License...

    Science.gov (United States)

    2011-04-14

    ... Energy Regulatory Commission Turlock Irrigation District and Modesto Irrigation District; Notice of..., 2011. d. Submitted By: Turlock Irrigation District and Modesto Irrigation District. e. Name of Project... Regulatory Affairs, Turlock Irrigation District, P.O. Box 949, Turlock, California 95381, 209-883-8241...

  8. Mapping Irrigated Areas of Ghana Using Fusion of 30 m and 250 m Resolution Remote-Sensing Data

    Directory of Open Access Journals (Sweden)

    Arnel Rala

    2011-04-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  10. NEW SUNS IN THE COSMOS?

    Energy Technology Data Exchange (ETDEWEB)

    De Freitas, D. B.; Leao, I. C.; Lopes, C. E. Ferreira; Paz-Chinchon, F.; Canto Martins, B. L.; Alves, S.; De Medeiros, J. R. [Departamento de Fisica, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil); Catelan, M. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, 782-0436 Macul, Santiago (Chile)

    2013-08-20

    The present work reports on the discovery of three stars that we have identified to be rotating Sun-like stars, based on rotational modulation signatures inferred from light curves from the CoRoT mission's Public Archives. In our analysis, we performed an initial selection based on the rotation period and position in the period-T{sub eff} diagram. This revealed that the stars CoRoT IDs 100746852, 102709980, and 105693572 provide potentially good matches to the Sun with a similar rotation period. To refine our analysis, we applied a novel procedure, taking into account the fluctuations of the features associated with photometric modulation at different time intervals and the fractality traces that are present in the light curves of the Sun and of these ''New Sun'' candidates alike. In this sense, we computed the so-called Hurst exponent for the referred stars, for a sample of 14 CoRoT stars with sub- and super-solar rotational periods, and for the Sun itself in its active and quiet phases. We found that the Hurst exponent can provide a strong discriminant of Sun-like behavior, going beyond what can be achieved with solely the rotation period itself. In particular, we find that CoRoT ID 105693572 is the star that most closely matches the solar rotation properties as far as the latter's imprints on light curve behavior are concerned. The stars CoRoT IDs 100746852 and 102709980 have significant smaller Hurst exponents than the Sun, notwithstanding their similarity in rotation periods.

  11. Lemhi River Habitat Improvement Study, 1985 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Dorratcaque, Dennis E.

    1986-02-01

    The objective was to develop methods for improving anadromous fish passage in the Lemhi River in east central Idaho. Alternatives assessed include flow concentration, fish screen improvement, groundwater augmentation, groundwater irrigation, water withdrawal reduction, return flow improvement, sprinkler irrigation, storage, and trap and haul. (ACR)

  12. SunShot Initiative Portfolio Book 2014

    Energy Technology Data Exchange (ETDEWEB)

    Solar Energy Technologies Office

    2014-05-01

    The 2014 SunShot Initiative Portfolio Book outlines the progress towards the goals outlined in the SunShot Vision Study. Contents include overviews of each of SunShot’s five subprogram areas, as well as a description of every active project in the SunShot’s project portfolio as of May 2014.

  13. Stakeholder Views, Financing and Policy Implications for Reuse of Wastewater for Irrigation: A Case from Hyderabad, India

    Directory of Open Access Journals (Sweden)

    Markus Starkl

    2015-01-01

    Full Text Available When flowing through Hyderabad, the capital of Telangana, India, the Musi River picks up (partially treated and untreated sewage from the city. Downstream of the city, farmers use this water for the irrigation of rice and vegetables. Treatment of the river water before it is used for irrigation would address the resulting risks for health and the environment. To keep the costs and operational efforts low for the farmers, the use of constructed wetlands is viewed as a suitable option. Towards this end, the paper investigates the interests and perceptions of government stakeholders and famers on the treatment of wastewater for irrigation and further explores the consumer willingness to pay a higher price for cleaner produced vegetables. Full cost recovery from farmers and consumers cannot be expected, if mass scale treatment of irrigation water is implemented. Instead, both consumers and farmers would expect that the government supports treatment of irrigation water. Most stakeholders associated with the government weigh health and environment so high, that these criteria outweigh cost concerns. They also support the banning of irrigation with polluted water. However, fining farmers for using untreated river water would penalize them for pollution caused by others. Therefore public funding of irrigation water treatment is recommended.

  14. Generic E. coli levels in surface and nontraditional irrigation water in the mid Atlantic in relation to FSMA water quality standards: A CONSERVE study

    Science.gov (United States)

    Introduction: The use of surface (pond and river) and nontraditional (reclaimed wastewater, produce wash water) irrigation water (SNIW) could reduce stress on ground water resources. However, it is essential to understand how these irrigation sources may influence the microbiological safety of fresh...

  15. Irrigation Controllers Specification and Certification

    Science.gov (United States)

    WaterSense labeled irrigation controllers, which act like a thermostat for your sprinkler system telling it when to turn on and off, use local weather and landscape conditions to tailor watering schedules to actual conditions on the site.

  16. Irrigation Sprinklers Notice of Intent

    Science.gov (United States)

    High-efficiency irrigation sprinklers aim to deliver water more evenly to the landscape than traditional sprinklers and/or regulate outlet pressure to ensure a constant flow rate over a range of supply pressures.

  17. Swing Set Irrigation System

    Directory of Open Access Journals (Sweden)

    Ambe Verma

    2015-05-01

    Full Text Available ABSTRACT India is a vast country based on agriculture and irrigation is the most important factor for agriculture. In India there are many sources provide for irrigation. Every day new technologies are emerged in the world which brings a revolutionary change in the nature of this world. day by day the energy resources used by the large population of this world are coming on the last stage This project give the idea that how the other different form of energy can be used and implemented efficiently to overcome from this problem The aim of this project is to achieve the objective of energy lasting problem which is likely to be faced over in coming decades. Energy lasting is a big problem in India. This is faced by every people who live in the country. Swing energy is the form of energy. In this paper we have represented the methodology of swing energy using for rural area of application. This paper is all about Swing Set Water Pump in which the water pump will execute with the help of a swing set of canopy type. As we need a motor to operate the water pump but in this project we use the swing in the place of motor and we use oscillatory motion of swing in the place of rotating motion of a motor. Everybody has needed the energy at an increasing rate ever since he came on the Earth. Because of this lot of energy has been exhausted and wasted. All the member are dedicated the amount of their important time to participate in multiple meetings read and research for making the content to the report. We would especially like to thanks for the efficient condition of the entire Advisory member and their experiences. This study was initial and performed within the BUDDHA INSTITUTE OF TECHNOLOGY GIDA Gorakhpur the final report represents the labour and interest of the entire member working for this project. Finally we would like to thanks to all the member of our college workshop who helped us in manufacturing of this project model.

  18. Effect of the Irrigation Canal Network on Surface and Groundwater Interactions in the Lower Valley of the Cachapoal River, Chile Efecto de la Red de Canales de Riego en las Interacciones de Agua Superficial y Subterránea en la Parte Baja del Valle Del Río Cachapoal, Chile

    Directory of Open Access Journals (Sweden)

    José Luis Arumí

    2009-03-01

    Full Text Available Agricultural production of high value crops in Chile's Central Valley is highly dependent on surface and groundwater resources. They are connected and together form an integrated hydrological system, the individual components of which have to be studied. This research is addressed to answering two questions: 1 to what extent do irrigation and canal seepage contribute to groundwater recharge and 2 what is the influence of the interactions between the Cachapoal River and ground water. The study was carried out from 2003 to 2007 in Peumo Valley (34.3° S, 71.3° W. In winter, the irrigation canal network intercepts and diverts surface runoff, which flows to flat areas and recharges groundwater. In summer, infiltration from the canals recharges the aquifer directly and partially compensates for water uptake from plants and evaporation. The effects of both interactions keep groundwater at a relatively constant level over the whole year. The water balance of the valley is strongly affected by agricultural practices, groundwater recharge mainly originating from irrigation loss (22% and canal seepage (52%. It is important to know how management decisions, such as change in irrigation practices or canal lining, can affect the hydrological system and agricultural production within the valley.La producción agrícola de exportación en la Zona Central de Chile es altamente dependiente de los recursos hídricos superficiales y subterráneos, los que a su vez están conectados formando un solo sistema hidrológico a través de procesos que no están bien estudiados. Esta investigación apunta a responder dos preguntas de trabajo: 1 Entender el efecto de las filtraciones de los canales de riego en la recarga de los sistemas de aguas subterráneas; y 2 Identificar los patrones de interacción entre las aguas subterráneas y superficiales en el valle de Peumo. Este estudio se ejecutó entre los años 2003 y 2007 en el valle de Peumo, localizado en a Tercera

  19. Research on the Effect of the Future Adjustment of Agricultural Water Pricing Based on the Resource and Environment Water Price on the Quantity of Irrigation Water in Tarim River Basin%基于资源环境水价的塔里木河流域农业水价的节水效应

    Institute of Scientific and Technical Information of China (English)

    孙建光; 韩桂兰

    2012-01-01

    According to the models of water fees and environment water prices and relevant data, on the basis of the cost price of water supply, this paper further calculates the future agricultural water price based on water resources fee and environment water prices. Then the paper establishes the model of the effect of agricultural water price on the quantity of irrigation water in Tarim River Basin by using the data of agricultural water prices and the amount of irrigation water use in the basin, and it is used to analyze the effect of the future adjustment of agricultural water prices based on different agricultural saving water prices two elastic parameters of de- mand of water prices(adjusted and unadjusted) ~ the results indicate that the effect of the adjustment of the future agricultural water on the quantity of irrigational water is very high, but the function of the environmental water price is to carry out the economical compensation of the environmental water use to protect the ecological environment in Tarim River Basin. It is the key approach to improving the effects of the future agricultural water prices by the cooperation of the adjustment of water prices with the high effec- tive water-saving techniques. Especially the research of the effect of saving water of the future agricultural water price is related to the safety of food production and the issue of the farmer's carrying capacity of water prices, is the key contents for the future adjustment of agricultural water priees to discuss, so that the research can be used to guide the future a~ricultural wztor nri~qncr%在塔里木河流域农业供水成本水价基础上,基于已有研究的流域水资源费和环境水价模型与相关资料,首先构建了流域基于资源环境水价的未来农业水价;然后,利用流域农业水价和灌水量资料构建了流域农业水价的需求效应模型,分析了未来塔河流域基于资源环境水价的未来农业水价的节水效应

  20. 78 FR 3892 - Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status

    Science.gov (United States)

    2013-01-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status On January 9, 2013, the Modesto Irrigation District (Modesto) filed a motion...

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

    Science.gov (United States)

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

    2013-05-01

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

  2. 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.

  3. Earth's Heat Source - The Sun

    CERN Document Server

    Manuel, Oliver K

    2009-01-01

    The Sun encompasses planet Earth, supplies the heat that warms it, and even shakes it. The United Nation Intergovernmental Panel on Climate Change (IPCC) assumed that solar influence on our climate is limited to changes in solar irradiance and adopted the consensus opinion of a Hydrogen-filled Sun, the Standard Solar Model (SSM). They did not consider the alternative solar model and instead adopted another consensus opinion: Anthropogenic greenhouse gases play a dominant role in climate change. The SSM fails to explain the solar wind, solar cycles, and the empirical link of solar surface activity with Earth changing climate. The alternative solar model, that was molded from an embarrassingly large number of unexpected observations revealed by space-age measurements since 1959, explains not only these puzzles but also how closely linked interactions between the Sun and its planets and other celestial bodies induce turbulent cycles of secondary solar characteristics that significantly affect Earth climate.

  4. Parameter Estimation for Groundwater Models under Uncertain Irrigation Data.

    Science.gov (United States)

    Demissie, Yonas; Valocchi, Albert; Cai, Ximing; Brozovic, Nicholas; Senay, Gabriel; Gebremichael, Mekonnen

    2015-01-01

    The success of modeling groundwater is strongly influenced by the accuracy of the model parameters that are used to characterize the subsurface system. However, the presence of uncertainty and possibly bias in groundwater model source/sink terms may lead to biased estimates of model parameters and model predictions when the standard regression-based inverse modeling techniques are used. This study first quantifies the levels of bias in groundwater model parameters and predictions due to the presence of errors in irrigation data. Then, a new inverse modeling technique called input uncertainty weighted least-squares (IUWLS) is presented for unbiased estimation of the parameters when pumping and other source/sink data are uncertain. The approach uses the concept of generalized least-squares method with the weight of the objective function depending on the level of pumping uncertainty and iteratively adjusted during the parameter optimization process. We have conducted both analytical and numerical experiments, using irrigation pumping data from the Republican River Basin in Nebraska, to evaluate the performance of ordinary least-squares (OLS) and IUWLS calibration methods under different levels of uncertainty of irrigation data and calibration conditions. The result from the OLS method shows the presence of statistically significant (p irrigation pumping uncertainties during the calibration procedures, the proposed IUWLS is able to minimize the bias effectively without adding significant computational burden to the calibration processes.

  5. Irrigation infrastructure and water appropriation rules for food security

    Science.gov (United States)

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

    2015-01-01

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

  6. Parameter estimation for groundwater models under uncertain irrigation data

    Science.gov (United States)

    Demissie, Yonas; Valocchi, Albert J.; Cai, Ximing; Brozovic, Nicholas; Senay, Gabriel; Gebremichael, Mekonnen

    2015-01-01

    The success of modeling groundwater is strongly influenced by the accuracy of the model parameters that are used to characterize the subsurface system. However, the presence of uncertainty and possibly bias in groundwater model source/sink terms may lead to biased estimates of model parameters and model predictions when the standard regression-based inverse modeling techniques are used. This study first quantifies the levels of bias in groundwater model parameters and predictions due to the presence of errors in irrigation data. Then, a new inverse modeling technique called input uncertainty weighted least-squares (IUWLS) is presented for unbiased estimation of the parameters when pumping and other source/sink data are uncertain. The approach uses the concept of generalized least-squares method with the weight of the objective function depending on the level of pumping uncertainty and iteratively adjusted during the parameter optimization process. We have conducted both analytical and numerical experiments, using irrigation pumping data from the Republican River Basin in Nebraska, to evaluate the performance of ordinary least-squares (OLS) and IUWLS calibration methods under different levels of uncertainty of irrigation data and calibration conditions. The result from the OLS method shows the presence of statistically significant (p irrigation pumping uncertainties during the calibration procedures, the proposed IUWLS is able to minimize the bias effectively without adding significant computational burden to the calibration processes.

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

    Science.gov (United States)

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

    2015-02-01

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

  8. Significant impacts of irrigation water sources and methods on modeling irrigation effects in the ACME Land Model

    Energy Technology Data Exchange (ETDEWEB)

    Leng, Guoyong; Leung, Lai-Yung; Huang, Maoyi

    2017-07-01

    An irrigation module that considers both irrigation water sources and irrigation methods has been incorporated into the ACME Land Model (ALM). Global numerical experiments were conducted to evaluate the impacts of irrigation water sources and irrigation methods on the simulated irrigation effects. All simulations shared the same irrigation soil moisture target constrained by a global census dataset of irrigation amounts. Irrigation has large impacts on terrestrial water balances especially in regions with extensive irrigation. Such effects depend on the irrigation water sources: surface-water-fed irrigation leads to decreases in runoff and water table depth, while groundwater-fed irrigation increases water table depth, with positive or negative effects on runoff depending on the pumping intensity. Irrigation effects also depend significantly on the irrigation methods. Flood irrigation applies water in large volumes within short durations, resulting in much larger impacts on runoff and water table depth than drip and sprinkler irrigations. Differentiating the irrigation water sources and methods is important not only for representing the distinct pathways of how irrigation influences the terrestrial water balances, but also for estimating irrigation water use efficiency. Specifically, groundwater pumping has lower irrigation water use efficiency due to enhanced recharge rates. Different irrigation methods also affect water use efficiency, with drip irrigation the most efficient followed by sprinkler and flood irrigation. Our results highlight the importance of explicitly accounting for irrigation sources and irrigation methods, which are the least understood and constrained aspects in modeling irrigation water demand, water scarcity and irrigation effects in Earth System Models.

  9. The use and re-use of unsustainable groundwater for irrigation: a global budget

    Science.gov (United States)

    Grogan, Danielle S.; Wisser, Dominik; Prusevich, Alex; Lammers, Richard B.; Frolking, Steve

    2017-03-01

    Depletion of groundwater aquifers across the globe has become a significant concern, as groundwater is an important and often unsustainable source of irrigation water. Simultaneously, the field of water resource management has seen a lively debate over the concepts and metrics used to assess the downstream re-use of agricultural runoff, with most studies focusing on surface water balances. Here, we bring these two lines of research together, recognizing that depletion of aquifers leads to large amounts of groundwater entering surface water storages and flows by way of agricultural runoff. While it is clear that groundwater users will be impacted by reductions in groundwater availability, there is a major gap in our understanding of potential impacts downstream of groundwater pumping locations. We find that the volume of unsustainable groundwater that is re-used for irrigation following runoff from agricultural systems is nearly as large as the volume initially extracted from reservoirs for irrigation. Basins in which the volume of irrigation water re-used is equal to or greater than the volume of water initially used (which is possible due to multiple re-use of the same water) contain 33 million hectares of irrigated land and are home to 1.3 billion people. Some studies have called for increasing irrigation efficiency as a solution to water shortages. We find that with 100% irrigation efficiency, global demand for unsustainable groundwater is reduced by 52%, but not eliminated. In many basins, increased irrigation efficiency leads to significantly decreased river low flows; increasing irrigation efficiency to 70% globally decreases total surface water supplies by ∽600 km3 yr-1. These findings illustrate that estimates of aquifer depletion alone underestimate the importance of unsustainable groundwater to sustaining surface water systems and irrigated agriculture.

  10. The Sun: Our Nearest Star

    Science.gov (United States)

    Adams, M. L.; Six, N. Frank (Technical Monitor)

    2002-01-01

    We have in our celestial backyard, a prime example of a variable star. The Sun, long thought to be "perfect" and unvarying, began to reveal its cycles in the early 1600s as Galileo Galilei and Christoph Scheiner used a telescope to study sunspots. For the past four hundred years, scientists have accumulated data, showing a magnetic cycle that repeats, on average, every eleven (or twenty-two) years. In addition, modern satellites have shown that the energy output at radio and x-ray wavelengths also varies with this cycle. This talk will showcase the Sun as a star and discuss how solar studies may be used to understand other stars.

  11. Effects of irrigation water supply variations on limited resource farming in Conejos County, Colorado

    Science.gov (United States)

    Eckert, Jerry B.; Wang, Erda

    1993-02-01

    Farms in NE Conejos County, Colorado, are characterized by limited resources, uncertain surface flow irrigation systems, and mixed crop-livestock enterprise combinations which are dependent on public grazing resources. To model decision making on these farms, a linear program is developed stressing enterprise choices under conditions of multiple resource constraints. Differential access to grazing resources and irrigation water is emphasized in this research. Regarding the water resource, the model reflects farms situated alternatively on high-, medium-, and low-priority irrigation ditches within the Alamosa-La Jara river system, each with and without supplemental pumping. Differences are found in optimum enterprise mixes, net returns, choice of cropping technology, level of marketings, and other characteristics in response to variations in the availability of irrigation water. Implications are presented for alternative improvement strategies.

  12. Selection of Low Pollution Planting Model in Yellow River Irrigation Areas of Ningxia%宁夏引黄灌区低污染种植模式筛选

    Institute of Scientific and Technical Information of China (English)

    刘根红; 许强; 康建宏; 吴宏亮; 赵亚慧

    2012-01-01

    In order to reduce the nitrogen and phosphorus loss of farmland and give consideration to both the economic and social benefits, twelve traditional and assembled planting patterns were comprehensively evaluated with AHP by comparing with the planting pattern of spring wheat intercropped with corn. The planting model beneficial to reducing the nitrogen and phosphorus contens of farmland in the irrigation areas was selected. Results showed that it was very important for reducing soil nitrogen and phosphorus contents through prolonging soil covered time with crop. Taking into consideration both the yield and economic benefits, four low pollution planting models of rice after winter wheat, silage after winter wheat, oil sunflower after winter wheat and Chinese cabbage after winter wheat were selected.%在对宁夏引黄灌区现有主要种植模式的选择及组装基础上,运用层次分析法,以春小麦/玉米(套作)为对照,以降低农田氮磷流失量为主要目标,兼顾经济效益及社会效益,对选择和新组装的12种种植模式进行综合评价,选择出利于灌区农田氮磷残留量相对较低的种植模式.结果表明,作物生长期间,相对增加田面的覆盖时间,对降低土壤及退水氮磷残留具有重要意义,同时,兼顾产量和经济效益,选择出冬小麦-水稻(同年复种)、冬小麦-青贮、冬小麦-油葵、冬小麦-大白菜4种较为理想的低污染种植模式.

  13. Development of Solar Powered Irrigation System

    Science.gov (United States)

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

    2013-12-01

    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.

  14. 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.

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

    Science.gov (United States)

    Nkhoma, Bryson; Kayira, Gift

    2016-04-01

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

  16. Day the sun went out

    CERN Multimedia

    2007-01-01

    "A new british sci-fi movie envisages the death of the sun not in billions of years, but in decades. And, amazingly, the film's scientific adviser says this may not be so far from the truth..." (1/2 page)

  17. Effects of Early Sun Exposure

    Science.gov (United States)

    ... can be harmful. It can lead to:Skin changes. Some skin cells with melanin can form a clump. This creates freckles and moles. Over time, these can develop cancer.Early aging. Time spent in the sun makes your skin age faster than normal. Signs of this are wrinkled, tight, or leathery ...

  18. Tracking Planets around the Sun

    Science.gov (United States)

    Riddle, Bob

    2008-01-01

    In earlier columns, the celestial coordinate system of hour circles of right ascension and degrees of declination was introduced along with the use of an equatorial star chart (see SFA Star Charts in Resources). This system shows the planets' motion relative to the ecliptic, the apparent path the Sun follows during the year. An alternate system,…

  19. How Bright Is the Sun?

    Science.gov (United States)

    Berr, Stephen

    1991-01-01

    Presents a sequence of activities designed to allow eighth grade students to deal with one of the fundamental relationships that govern energy distribution. Activities guide students to measure light bulb brightness, discover the inverse square law, compare light bulb light to candle light, and measure sun brightness. (two references) (MCO)

  20. Tracking Planets around the Sun

    Science.gov (United States)

    Riddle, Bob

    2008-01-01

    In earlier columns, the celestial coordinate system of hour circles of right ascension and degrees of declination was introduced along with the use of an equatorial star chart (see SFA Star Charts in Resources). This system shows the planets' motion relative to the ecliptic, the apparent path the Sun follows during the year. An alternate system,…

  1. Teaching transanal irrigation for functional bowel disorders.

    Science.gov (United States)

    Coggrave, Maureen; Norton, Christine

    Transanal irrigation of the bowel in the management of functional bowel disorders is currently receiving increased attention following the recent introduction of the Peristeen irrigation kit (Coloplast Ltd) in April 2007. Irrigation provides a welcome additional choice in the limited range of available interventions for the management of these patients. However, evidence to support clinical practice around irrigation is limited and nursing knowledge and experience of irrigation is only just developing. This paper reports a series of master classes conducted to support and develop the use of irrigation in the UK, and demonstrates the value of the master class as an educational tool when introducing a novel therapy.

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

    Science.gov (United States)

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

    2009-01-01

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

  3. D-Area Drip Irrigation/Phytoremediation Project: SRTC Report on Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W.

    2001-09-11

    The overall objective of this project is to evaluate a novel drip irrigation-phytoremediation process for remediating volatile organic contaminants (VOCs), primarily trichloroethylene (TCE), from groundwater in D-Area at the Savannah River Site (SRS). The process is expected to be less expensive and more beneficial to the environment than alternative TCE remediation technologies.

  4. Assessment of indicator bacteria and Aeromonas spp. in surface and nontraditional irrigation water: a conserve study

    Science.gov (United States)

    Introduction: The use of surface and nontraditional irrigation water (SNIW) (pond, tidal and non-tidal river water, reclaimed wastewater) is one way to conserve groundwater. However, SNIW may serve as reservoirs and vehicles for under-recognized enteric pathogens, spreading localized contamination d...

  5. 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

  6. Estimating actual irrigation application by remotely sensed evapotranspiration observations

    NARCIS (Netherlands)

    Droogers, P.; Immerzeel, W.W.; Lorite, I.J.; SWAP, PEST

    2010-01-01

    Water managers and policy makers need accurate estimates of real (actual) irrigation applications for effective monitoring of irrigation and efficient irrigation management. However, this information is not readily available at field level for larger irrigation areas. An innovative inverse modeling

  7. The Sun Radio Imaging Space Experiment (SunRISE) Mission

    Science.gov (United States)

    Lazio, Joseph; Kasper, Justin; Maksimovic, Milan; Alibay, Farah; Amiri, Nikta; Bastian, Tim; Cohen, Christina; Landi, Enrico; Manchester, Ward; Reinard, Alysha; Schwadron, Nathan; Cecconi, Baptiste; Hallinan, Gregg; Hegedus, Alex; Krupar, Vratislav; Zaslavsky, Arnaud

    2017-04-01

    Radio emission from coronal mass ejections (CMEs) is a direct tracer of particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Energized electrons excite Langmuir waves, which then convert into intense radio emission at the local plasma frequency, with the most intense acceleration thought to occur within 20 RS. The radio emission from CMEs is quite strong such that only a relatively small number of antennas is required to detect and map it, but many aspects of this particle acceleration and transport remain poorly constrained. Ground-based arrays would be quite capable of tracking the radio emission associated with CMEs, but absorption by the Earth's ionosphere limits the frequency coverage of ground-based arrays (ν ≳ 15 MHz), which in turn limits the range of solar distances over which they can track the radio emission (≲ 3RS). The state-of-the-art for tracking such emission from space is defined by single antennas (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by assuming a frequency-to-density mapping; there has been some success in triangulating the emission between the spacecraft, but considerable uncertainties remain. We describe the Sun Radio Imaging Space Experiment (SunRISE) mission concept: A constellation of small spacecraft in a geostationary graveyard orbit designed to localize and track radio emissions in the inner heliosphere. Each spacecraft would carry a receiving system for observations below 25 MHz, and SunRISE would produce the first images of CMEs more than a few solar radii from the Sun. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

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

    Science.gov (United States)

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

    2015-12-01

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

  9. Sustainable irrigation in fruit trees

    Directory of Open Access Journals (Sweden)

    Cristos Xiloyannis

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

  10. Effluent polishing via pasture irrigation in Harare, Zimbabwe.

    Science.gov (United States)

    Nhapi, I; Mawere, M; Veenstra, S; Gijzen, H J

    2002-01-01

    Harare, the capital city of Zimbabwe, is experiencing eutrophication-related problems in its downstream potable water supply source of Lake Chivero. This is due mainly to poorly treated sewage effluent encroachment into upstream rivers, especially Marimba River. Crowborough Pasture Irrigation farm is in the Marimba sub-catchment area and has 305 hectares of irrigated pastures. Studies started from July 2000 to August 2001 focusing on the pasture's management of nutrients (nitrogen and phosphorus) and their impact on Marimba River. Water and nutrient balances were developed. Reduction efficiencies for this pasture were found to be 84% for TN and 54% for TP. Both the Crowborough sewage treatment works and the pastures are overloaded. It was therefore concluded that the current system is no longer sustainable economically and environmentally. From the results of our study we recommend that additional treatment units be constructed at Crowborough sewage treatment works to meet current flows. Moreover, pasture management needs substantial improvement. Nutrient recovery should be enhanced by regular harvesting of pasture grass and converting cow dung into an economic commodity as manure for neighbouring residents. Maize cultivation is also recommended to replace pasture grass as it is a local staple crop and has high nutrient uptake rates.

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

    Science.gov (United States)

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

    2015-12-01

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

  12. Scale transformation of utilization coefficient of irrigation water in riverine irrigation district%河网区灌溉水利用系数的尺度转换

    Institute of Scientific and Technical Information of China (English)

    俞双恩; 于智恒; 郭杰; 顾京; 李彧玮; 佘冬立

    2015-01-01

    irrigation districts in riverine area is that there is no unified water diversion, and several small irrigation districts usually merge into a larger one. The area is a typical self-similar system. The existence and reusing of the agricultural returning water have induced much debates about the real water-saving potential of the irrigation districts in riverine area, and also the scale effect of utilization coefficient of irrigation water. The paper selected the rice irrigation districts of Yancheng City in Lixiahe riverine region as the experimental object. The study area is flat, where the river and ditch network are densely distributed. Totally, 4 large-scale irrigation districts, 11 medium-scale and 32 small-scale irrigation districts were selected to measure and calculate the utilization coefficient of irrigation water by inclusive method. The utilization coefficients of irrigation water in sampling irrigation districts with different scales were measured in 9 counties in 2012-2013. Fractal characteristics of these riverine irrigation districts were analyzed based on fractal theory. In addition, box dimensions of the Yancheng riverine area and the irrigation districts with different scales were respectively calculated by box-counting method. The box dimension ranged from 1.703 to 1.966, and increased with the increasing of irrigation district area scale. The scale transformation model of utilization coefficient of irrigation water was established based on the relationships among utilization coefficient of irrigation water, irrigation area and box dimension. The calibration results verified that the scale transformation model could predict the utilization coefficient of irrigation water in the riverine irrigation district with high prediction accuracy. With the developed model, the scale transformation of utilization coefficient of irrigation water was performed successfully. This study provides a new way to analyze the utilization coefficients of irrigation water and

  13. Tanel Padar & The Sun veab õhukitarri

    Index Scriptorium Estoniae

    2008-01-01

    Õhukitarri Eesti meistrivõistlustest 19. apr. Tallinnas Rock Cafés (võistluste eestvedajaks on ansambel Tanel Padar & The Sun, kes samas esitleb oma esimest ingliskeelset albumit "Here Comes The Sun")

  14. Tanel Padar & The Sun veab õhukitarri

    Index Scriptorium Estoniae

    2008-01-01

    Õhukitarri Eesti meistrivõistlustest 19. apr. Tallinnas Rock Cafés (võistluste eestvedajaks on ansambel Tanel Padar & The Sun, kes samas esitleb oma esimest ingliskeelset albumit "Here Comes The Sun")

  15. 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.

  16. Impact of Irrigated Agroecosystems on Groundwater Resources in the US High Plains and North China Plain

    Science.gov (United States)

    Scanlon, B. R.; Longuevergne, L.; Cao, G.; Shen, Y.; Gates, J. B.; Reedy, R. W.; Zheng, C.

    2010-12-01

    the monitoring well network are attributed to regional overestimation of groundwater level declines from monitoring wells in urban regions. Many strategies are being evaluated to move towards more sustainable water resource management. Transfer of water from the Yangste River to the NCP should relieve some of the water stress in the region. Other proposed approaches include more efficient irrigation, deficit irrigation, mulching, crop rotation, and no irrigation. Future system management needs to consider tradeoffs between water consumption, crop yield, and lifespan of these aquifers.

  17. 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.

  18. 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 locat

  19. 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 locat

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

    NARCIS (Netherlands)

    Urrutia Cobo, N.

    2006-01-01

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

  1. 75 FR 43958 - Turlock Irrigation District and Modesto Irrigation District; Notice of Application for Amendment...

    Science.gov (United States)

    2010-07-27

    ... Energy Regulatory Commission Turlock Irrigation District and Modesto Irrigation District; Notice of...: May 24, 2010. d. Applicant: Turlock Irrigation District and Modesto Irrigation District. e. Name of.... g. Filed Pursuant to: Federal Power Act, 16 USC 791a-825r. h. Applicant Contact: Turlock...

  2. Cotton irrigation timing with variable seasonal irrigation capacities in the Texas south plains.

    Science.gov (United States)

    Within the Ogallala Aquifer Region of Texas, the irrigation capacity (IC) for a given field often changes within a growing season due to seasonal depletion of the aquifer, in season changes in crop irrigation needs in dry years, or consequences of irrigation volume limits imposed by irrigation distr...

  3. 75 FR 35778 - Modesto Irrigation District and Turlock Irrigation District; Notice of Preliminary Permit...

    Science.gov (United States)

    2010-06-23

    ... Energy Regulatory Commission Modesto Irrigation District and Turlock Irrigation District; Notice of... Competing Applications June 16, 2010. On February 1, 2010, Modesto Irrigation District and Turlock Irrigation District filed an application for a preliminary permit, pursuant to section 4(f) of the...

  4. SURDEV: surface irrigation software; design, operation, and evaluation of basin, border, and furrow irrigation

    NARCIS (Netherlands)

    Jurriëns, M.; Zerihun, D.; Boonstra, J.; Feyen, J.

    2001-01-01

    SURDEV is a computer package for the design, operation, and evaluation of surface irrigation. SURDEV combines three sub-programs: BASDEV (for basin irrigation), FURDEV (for furrow irrigation), and BORDEV for (border irrigation). This combination enables the user to simulate many of the problems invo

  5. SURDEV: surface irrigation software; design, operation, and evaluation of basin, border, and furrow irrigation

    NARCIS (Netherlands)

    Jurriëns, M.; Zerihun, D.; Boonstra, J.; Feyen, J.

    2001-01-01

    SURDEV is a computer package for the design, operation, and evaluation of surface irrigation. SURDEV combines three sub-programs: BASDEV (for basin irrigation), FURDEV (for furrow irrigation), and BORDEV for (border irrigation). This combination enables the user to simulate many of the problems

  6. 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 locat

  7. Measuring Transpiration to Regulate Winter Irrigation Rates

    Energy Technology Data Exchange (ETDEWEB)

    Samuelson, Lisa [Auburn University

    2006-11-08

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

  8. Caddo Sun Accounts across Time and Place

    Science.gov (United States)

    Gerona, Carla

    2012-01-01

    Billy Day, a Tunica/Biloxi, recently described the significance of the sun for Caddoan people. Day quoted an "old Caddo relative" of his who said: "I used to go outside and hold my hands up and bless myself with the sun--'a'hat.' Well, I can't do that anymore because they say we are sun worshipers. We didn't worship the sun. We worshiped what was…

  9. Global Warming Blame the Sun

    CERN Document Server

    Calder, N

    1997-01-01

    Concern about climate change reaches a political peak at a UN conference in Kyoto, 1-10 December, but behind the scenes the science is in turmoil. A challenge to the hypothesis that greenhouse gases are responsible for global warming comes from the discovery that cosmic rays from the Galaxy are involved in making clouds (Svensmark and Friis-Christensen, 1997). During the 20th Century the wind from the Sun has grown stronger and the count of cosmic rays has diminished. With fewer clouds, the EarthÕs surface has warmed up. This surprising mechanism explains the link between the Sun and climate change that astronomers and geophysicists have suspected for 200 years.

  10. Total eclipses of the sun.

    Science.gov (United States)

    Zirker, J B

    1980-12-19

    Total eclipses of the sun offer research opportunities in a variety of sciences. Some of the advances in solar physics resulting from eclipse observations are discussed. Experiments at the total eclipse of 16 February 1980 in India are also described. These included a test of general relativity, studies in coronal physics, investigations of solar prominences, diameter measurements, a search for interplanetary dust, a study of the gravity waves in the earth's atmosphere, and experiments on the biological effects on animals and humans.

  11. Revisiting SU(N) integrals

    CERN Document Server

    Zuber, Jean-Bernard

    2016-01-01

    In this note, I revisit integrals over $\\SU(N)$ of the form $ \\int DU\\, U_{i_1j_1}\\cdots U_{i_pj_p}\\Ud_{k_1l_1}\\cdots \\Ud_{k_nl_n}$. While the case $p=n$ is well known, it seems that explicit expressions for $p=n+N$ had not appeared in the literature. Similarities and differences, in particular in the large $N$ limit, between the two cases are discussed

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

    Science.gov (United States)

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

    2015-07-01

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

  13. Coherent States with SU(N) Charges

    CERN Document Server

    Mathur, M; Mathur, Manu; Paul, Samir K.

    2003-01-01

    We define coherent states carrying SU(N) charges by exploiting generalized Schwinger boson representation of SU(N) Lie algebra. These coherent states are defined on $2 (2^{N - 1} - 1)$ complex planes. They satisfy continuity property and provide resolution of identity. We also exploit this technique to construct the corresponding non-linear SU(N) coherent states.

  14. The Sun Rises on the Solar Sector

    OpenAIRE

    Ahmad, Reyaz A.

    2009-01-01

    Energy from the sun is abundant and free. Solar energy is in essence electromagnetic radiation emitted from the sun. Earth's climate, hydrologic systems, and ecosystems all derive from the sun. Other forms of renewable power such as wind, wave, biomass, and hydro are an indirect function of solar radiation.

  15. The Sun A User's Manual

    CERN Document Server

    Vita-Finzi, Claudio

    2008-01-01

    The Sun is an account of the many ways in which our nearest star affects our planet, how its influence has changed over the last few centuries and millennia, and the extent to which we can predict its future impact. The Sun's rays foster the formation of Vitamin D by our bodies, but it can also promote skin cancer, cataracts, and mutations in our DNA. Besides providing the warmth and light essential to most animal and plant life, solar energy contributes substantially to global warming. Although the charged particles of the solar wind shield us from harmful cosmic rays, solar storms may damage artificial satellites and cripple communication systems and computer networks. The Sun is the ideal renewable energy source, but its exploitation is still bedevilled by the problems of storage and distribution. Our nearest star, in short, is a complex machine which needs to be treated with caution, and this book will equip every reader with the knowledge that is required to understand the benefits and dangers it can bri...

  16. The faint young Sun problem

    CERN Document Server

    Feulner, Georg

    2012-01-01

    For more than four decades, scientists have been trying to find an answer to one of the most fundamental questions in paleoclimatology, the `faint young Sun problem'. For the early Earth, models of stellar evolution predict a solar energy input to the climate system which is about 25% lower than today. This would result in a completely frozen world over the first two billion years in the history of our planet, if all other parameters controlling Earth's climate had been the same. Yet there is ample evidence for the presence of liquid surface water and even life in the Archean (3.8 to 2.5 billion years before present), so some effect (or effects) must have been compensating for the faint young Sun. A wide range of possible solutions have been suggested and explored during the last four decades, with most studies focusing on higher concentrations of atmospheric greenhouse gases like carbon dioxide, methane or ammonia. All of these solutions present considerable difficulties, however, so the faint young Sun prob...

  17. Climate Change and Increased Irrigation Demands: What Is Left for Hydropower Generation? Results from Two Semi-Arid Basins

    Directory of Open Access Journals (Sweden)

    Tor Haakon Bakken

    2016-03-01

    Full Text Available In this study, we have modelled the effect of climate change and increased irrigation withdrawals on the available water for hydropower production in two semi-arid river basins, i.e., Kizilirmak (Turkey and Devoll (Albania, and the role of the reservoirs. The combined effect of climate change and extended irrigation withdrawals will overall lead to reduced runoff in the rivers, according to our simulations. The changes will be most dramatic at Kizilirmak, reducing the water available for hydropower production. The presence of the reservoirs will lead to extended water use/losses due to the provision of regulated flow, enabling larger irrigation withdrawals and increasing the evaporative losses from the reservoir surfaces. Comparing the water consumption losses at Kizilirmak, the irrigation losses are in the range of 2–4 times larger than the gross evaporation losses from reservoir surfaces. The reservoirs at Devoll will improve water availability for hydropower production during low flow periods, and the upstream irrigation represents presently a low risk to the downstream power producers. As the results are sensitive to specific river basin characteristics and the assumptions made, the results cannot be generalized to other river basins without taking these specifics into consideration.

  18. Water reuse for urban landscape irrigation: aspersion and health related regulations.

    Science.gov (United States)

    Brissaud, F; Blin, E; Hemous, S; Garrelly, L

    2008-01-01

    The Mediterranean seaside resort of Le Grau du Roi includes 40 hectares of landscaped areas spray irrigated with river water supplied through a separate network. Wastewater collected from several municipalities is treated in an activated sludge wastewater treatment plant (WWTP) and polished in waste stabilization ponds (WSPs). Planned substitution of treated wastewater for river water is hindered by spray irrigation prohibition within a 100 m distance from houses and recreational areas. WWTP and WSP effluents were monitored for pathogens with a particular attention to Legionella in Spring and Summer 2006. Helminth eggs, salmonellae and enteroviruses were never detected neither in WWTP effluent nor in the ponds. Legionella spp content was slightly higher or of the order of magnitude of river water contents. Regarding Legionella pneumophila contents, WSP effluent did not significantly differ from the river water. E.coli and enterococci contents in WSP effluents complied with the "excellent quality" criteria of the European Directive for coastal bathing waters. Therefore, substituting WSP effluents to river water is unlikely to alter health risks related to spray irrigation and, in this case, the buffer zone required by the French water reuse guidelines appears being short of support.

  19. Sun Savvy Students: Free Teaching Resources from EPA's SunWise Program

    Science.gov (United States)

    Hall-Jordan, Luke

    2008-01-01

    With summer in full swing and the sun is naturally on our minds, what better time to take advantage of a host of free materials provided by the U.S. Environmental Protection Agency's Sun Wise program. Sun Wise aims to teach students and teachers about the stratospheric ozone layer, ultraviolet (UV) radiation, and how to be safe while in the Sun.…

  20. Seasonal effects of irrigation on land-atmosphere latent heat, sensible heat and carbon fluxes in semi-arid basin

    Science.gov (United States)

    Xie, Zhenghui; Zeng, Yujin

    2017-04-01

    Irrigation, which constitutes 70% of the total amount of fresh water consumed by the human population, is significantly impacting the land-atmosphere fluxes. In this study, using the improved Community Land Model version 4.5 (CLM 4.5) with an active crop model, two high resolution ( 1 km) simulations investigating the effects of irrigation on Latent Heat (LH), Sensible Heat (SH) and Carbon Fluxes (or net ecosystem exchange, NEE) from land to atmosphere on the Heihe River Basin in northwestern China were conducted using a high-quality irrigation dataset compiled from 1981 to 2013. The model output and measurements from remote sensing demonstrated the capacity and viability of the developed models to reproduce ecological and hydrological processes. The results revealed the effects of irrigation on LH and SH are strongest during summer with a LH increase of 100 W/m2 and a SH decrease of 60 W/m2 over intensely irrigated areas. However, the reactions are much weaker during spring and autumn when there is much less irrigation. When the irrigation rate below 5 mm/day, the LH generally increases, whereas the SH decreases with growing irrigation rates. However, when the irrigation threshold is in excess of 5 mm/day, there is no accrued effect of irrigation on the LH and SH. Irrigation produces opposite effects to the NEE during spring and summer. During the spring, irrigation yields more discharged carbon from the land to the atmosphere, increasing the NEE value by 0.4-0.8 gC/m2/day, while the summer irrigation favors crop fixing of carbon from atmospheric CO2, decreasing the NEE value by 0.8 gC/m2/day. The repercussions of irrigation on land-atmosphere fluxes are not solely linked to the irrigation amount, and other parameters (especially the temperature) also control the effects of irrigation on LH, SH and NEE. The study indicates that how a land surface model with high spatial resolution can represent crop growing and its effects over basin scale.

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

    Science.gov (United States)

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

    2011-01-01

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

  2. Application of Landsat to Evaluate Effects of Irrigation Forbearance

    Directory of Open Access Journals (Sweden)

    Yutaka Hagimoto

    2013-08-01

    Full Text Available Thirty-meter resolution Landsat data were used to evaluate the effects of irrigation management in the Wood River Valley, Upper Klamath Basin, Oregon. In an effort to reduce water use and leave more of the water resource in-stream, 4,674 ha of previously flood irrigated pasture was managed as dryland pasture. Ground-based measurements over one irrigated and one unirrigated pasture site were used to monitor the difference in evapotranspiration (ET using the Bowen ratio-energy balance method. These data sets represent point measurements of the response to irrigation, but do not allow for the spatial integration of effects of irrigated versus unirrigated land treatment. Four Landsat scenes of the Wood River Valley during the 2004 growing season were evaluated using reconstructed METRIC algorithms. Comparisons of ET algorithm output with ground-based data for all components of the energy balance, including net radiation, soil heat flux, sensible heat flux and evapotranspiration, were made for the four scenes. The excellent net radiation estimates, along with reasonable estimates of the other components, are demonstrated along with the capability to integrate results to the basin scale.

  3. Quality of Irrigation Water and Soil Characteristics of Watari Irrigation Project

    Directory of Open Access Journals (Sweden)

    Adamu G.K

    2013-01-01

    Full Text Available This research was carried out in Watari River Irrigation Project, located on the slopes of Watari River valley in Bagwai local government of Kano state with aim of assessing soil properties and quality of irrigation water. A total of 32 representative soil samples were randomly collected from the eight sectors. Seven water samples were also collected from the sectors and the dam. The samples were treated and analyzed for physical, chemical and fertility related indices. Typically, the quality of irrigation water is assessed based on the salt and salt inducing contents, the presence and abundance of micro and macro nutrients, trace elements, alkalinity, acidity, hardness and the amount of suspended solids. The results are grouped into general quality parameters which included salinity and salt inducing cations and anions and pollutants. The Findings indicated that the mean pH ranged from 7.10 to 7.50, while the mean EC values across the sectors ranged from 50 to 60µS/m. The mean metal cations in the water ranged from 15.00 to 20.07; 5.41 to 16.22; 3.29 to 6.57; 14.83 to 15.00cmol/l for Na, Ca, Mg and K respectively. The SAR ranged from 6.87 to 10.17, while the range of TDS values was from 31.00 to 36.00mg/l. The mean carbonates concentration detected in the irrigation water was from 4.00 to 12.00cmol/l, while the mean bicarbonate content ranged from 22.00 to 55.00cmol/l. The ranges for chloride and nitrate were 9.87 to 31.58 and 1.00 to 1.65mg/kg respectively. The residual sodium carbonate (RSC ranged from 8.00 to 30.69.There was no detectable NH4 in the irrigation water. The results have shown that all the eight sectors had sand dominated texture. The mean pH in the soil ranged from 5.50 to 5.95. The EC ranged between 0.49 to 1.30cmol/kg, the Clranged between 0.29 to 1.07cmol/kg and SAR ranged between 0.13to 0.72. The mean soil organic carbon across the sectors ranged between 0.62 to 1.49%. The total nitrogen ranged between 0.0043 to 0

  4. Sediment transport in irrigation canals.

    NARCIS (Netherlands)

    Mendez V., N.J.

    1998-01-01

    The world population is rapidly increasing and is expected to double to about 10 billion by the year 2050. To support an increasing population in terms of food sufficiency, more and more water will be required. Irrigation is the most critical component of the modern package of inputs to effect high

  5. Sediment transport in irrigation canals

    NARCIS (Netherlands)

    Mendez V., N.J.

    1998-01-01

    The world population is rapidly increasing and is expected to double to about 10 billion by the year 2050. To support an increasing population in terms of food sufficiency, more and more water will be required. Irrigation is the most critical component of the modern package of inputs to

  6. Position paper : Whole bowel irrigation

    NARCIS (Netherlands)

    2004-01-01

    Whole bowel irrigation (WBI) should not be used routinely in the management of the poisoned patient. Although some volunteer studies have shown substantial decreases in the bioavailability of ingested drugs, no controlled clinical trials have been performed and there is no conclusive evidence that W

  7. Surface Water and Groundwater Interactions in Traditionally Irrigated Fields in Northern New Mexico, U.S.A.

    Directory of Open Access Journals (Sweden)

    Karina Y. Gutiérrez-Jurado

    2017-02-01

    Full Text Available Better understanding of surface water (SW and groundwater (GW interactions and water balances has become indispensable for water management decisions. This study sought to characterize SW-GW interactions in three crop fields located in three different irrigated valleys in northern New Mexico by (1 estimating deep percolation (DP below the root zone in flood-irrigated crop fields; and (2 characterizing shallow aquifer response to inputs from DP associated with irrigation. Detailed measurements of irrigation water application, soil water content fluctuations, crop field runoff, and weather data were used in the water budget calculations for each field. Shallow wells were used to monitor groundwater level response to DP inputs. The amount of DP was positively and significantly related to the total amount of irrigation water applied for the Rio Hondo and Alcalde sites, but not for the El Rito site. The average irrigation event DP using data for the complete irrigation season at each of the three sites was 77.0 mm at El Rito, 54.5 mm at Alcalde and 53.1 mm at Rio Hondo. Groundwater level rise compared to pre-irrigation event water levels ranged from 3 to 1870 mm, and was influenced by differences in irrigation practices between sites. Crop evapotranspiration estimates averaged across irrigation events were highest in Rio Hondo (22.9 mm, followed by El Rito (14.4 mm and Alcalde (10.4 mm. Results from this study indicate there are strong surface water-groundwater connections in traditionally irrigated systems of northern New Mexico, connections that may be employed to better manage groundwater recharge and river flow.

  8. Effects of climate change on water abstraction restrictions for irrigation during droughts - The UK case

    Science.gov (United States)

    Rey Vicario, D.; Holman, I.

    2016-12-01

    The use of water for irrigation and on-farm reservoir filling is globally important for agricultural production. In humid climates, like the UK, supplemental irrigation can be critical to buffer the effects of rainfall variability and to achieve high quality crops. Given regulatory efforts to secure sufficient environmental river flows and meet rising water demands due to population growth and climate change, increasing water scarcity is likely to compound the drought challenges faced by irrigated agriculture in this region. Currently, water abstraction from surface waters for agricultural irrigation can be restricted by the Environment Agency during droughts under Section 57 of the Water Resources Act (1991), based on abnormally low river flow levels and rainfall forecast, causing significant economic impacts on irrigated agricultural production. The aim of this study is to assess the impact that climate change may have on agricultural abstraction in the UK within the context of the abstraction restriction triggers currently in place. These triggers have been applied to the `Future Flows hydrology' database to assess the likelihood of increasing restrictions on agricultural abstraction in the future by comparing the probability of voluntary and compulsory restrictions in the baseline (1961-1990) and future period (2071-2098) for 282 catchments throughout the whole of the UK. The results of this study show a general increase in the probability of future agricultural irrigation abstraction restrictions in the UK in the summer, particularly in the South West, although there is significant variability between the 11 ensemble members. The results also indicate that UK winters are likely to become wetter in the future, although in some catchments the probability of abstraction restriction in the reservoir refilling winter months (November-February) could increase slightly. An increasing frequency of drought events due to climate change is therefore likely to lead to

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

    Directory of Open Access Journals (Sweden)

    Irit Eguavoen

    2012-10-01

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

  10. A Fuzzy Control Irrigation System For Cottonfield

    Science.gov (United States)

    Zhang, Jun; Zhao, Yandong; Wang, Yiming; Li, Jinping

    A fuzzy control irrigation system for cotton field is presented in this paper. The system is composed of host computer, slave computer controller, communication module, soil water sensors, valve controllers, and system software. A fuzzy control model is constructed to control the irrigation time and irrigation quantity for cotton filed. According to the water-required rules of different cotton growing periods, different irrigation strategies can be carried out automatically. This system had been used for precision irrigation of the cotton field in Langfang experimental farm of Soil and Fertilizer Institute, Chinese Academy of Agricultural Sciences in 2006. The results show that the fuzzy control irrigation system can improve cotton yield and save much water quantity than the irrigation system based on simple on-off control algorithm.

  11. Saline Ground Water and Irrigation Water on Root Zone Salinity

    Directory of Open Access Journals (Sweden)

    T. Subramani

    2014-06-01

    Full Text Available Salinisation of land and rivers is a problem of national importance in India. Appropriate land management options to alleviate salinisation should be chosen with knowledge of the effects of land management on stream flow, stream salinity, stream salt load and land productivity. The Management of Catchment Salinisation (MCS modelling approach has been described in earlier work. It links a one-dimensional soil water model with a groundwater model to investigate the effects of management options in study areas of approximately 50 km2. The one dimensional model is used to characterize the annual soil water balance as a function of underlying aquifer Vpotential for all required combinations of soil, vegetation and groundwater salinity. It includes the effect of salt accumulation on plant water use. A groundwater model is then used to estimate the depth to water table across the study area that reflects the topography, hydrogeology and the distribution of vegetation. The MCS model is used to investigate the potential effects of future land use scenarios on catchment salt and water balance. Land use scenarios that have been considered include: forest plantations, revegetation with native trees and shrubs, and development of small areas of crops (10 to 20 ha irrigated with groundwater. This project focuses on the development of small crop areas irrigated with groundwater and investigates the sustainability of these schemes. It also compares the reduction of catchment salt load export under irrigation development with the reduction under afforestation

  12. Conversion to drip irrigated agriculture may offset historic anthropogenic and wildfire contributions to sediment production.

    Science.gov (United States)

    Gray, A B; Pasternack, G B; Watson, E B; Goñi, M A; Hatten, J A; Warrick, J A

    2016-06-15

    This study is an investigation into the roles of wildfire and changing agricultural practices in controlling the inter-decadal scale trends of suspended sediment production from semi-arid mountainous rivers. In the test case, a decreasing trend in suspended sediment concentrations was found in the lower Salinas River, California between 1967 and 2011. Event to decadal scale patterns in sediment production in the Salinas River have been found to be largely controlled by antecedent hydrologic conditions. Decreasing suspended sediment concentrations over the last 15years of the record departed from those expected from climatic/hydrologic forcing. Sediment production from the mountainous headwaters of the central California Coast Ranges is known to be dominated by the interaction of wildfire and large rainfall/runoff events, including the Arroyo Seco, an ~700km(2) subbasin of the Salinas River. However, the decreasing trend in Salinas River suspended sediment concentrations run contrary to increases in the watershed's effective burn area over time. The sediment source area of the Salinas River is an order of magnitude larger than that of the Arroyo Seco, and includes a more complicated mosaic of land cover and land use. The departure from hydrologic forcings on suspended sediment concentration patterns was found to coincide with a rapid conversion of irrigation practices from sprinkler and furrow to subsurface drip irrigation. Changes in agricultural operations appear to have decreased sediment supply to the Salinas River over the late 20th to early 21st centuries, obscuring the influence of wildfire on suspended sediment production.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-08

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

  14. Micro technology based sun sensor

    DEFF Research Database (Denmark)

    Hales, Jan Harry; Pedersen, Martin; Fléron, René

    2003-01-01

    There is increasing interest among universities in the scientific and educational possibilities of picosatellites base on the CubeSat 5 concept. Due to sever mass and dimension constraints place on this type of satellites, new approaches and ideas regarding different systems arises to accommodate...... DTUsat sun sensors are needed along with a magnetometer to obtain unambiguous attitude determination for the ACDS and the payloads - an electrodynamic tether and a camera. The accuracy needed was not obtainable by employing conventional attitude sensors. Hence a linear slit sensor was designed...

  15. CHEMICAL COMPOSITION FROM THE DNIESTER RIVER TRIBUTARIES

    Directory of Open Access Journals (Sweden)

    V. Gladchi

    2013-06-01

    Full Text Available This article presents the results obtained in the framework of the project 09.832.08.06A. The role of the tributaries on formation of the Dniester river water and the study of the waters quality of sources / fountains in the catchment area of the Dniester river as sources of water supply and for irrigation in the State Program, Scientific Researches and of the management of waters quality.

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

    Science.gov (United States)

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

    2013-01-01

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

  17. Adaptability of Irrigation to a Changing Monsoon in India: How far can we go?

    Science.gov (United States)

    Zaveri, E.; Grogan, D. S.; Fisher-Vanden, K.; Frolking, S. E.; Wrenn, D. H.; Nicholas, R.

    2014-12-01

    Agriculture and the monsoon are inextricably linked in India. A large part of the steady rise in agricultural production since the onset of the Green Revolution in the 1960's has been attributed to irrigation. Irrigation is used to supplement and buffer crops against precipitation shocks, but water availability for such use is itself sensitive to the erratic, seasonal and spatially heterogeneous nature of the monsoon. We provide new evidence on the relationship between monsoon changes, irrigation variability and water availability by linking a process based hydrology model with an econometric model for one of the world's most water stressed countries. India uses more groundwater for irrigation than any other country, and there is substantial evidence that this has led to depletion of groundwater aquifers. First, we build an econometric model of historical irrigation decisions using detailed agriculture and weather data spanning 35 years. Multivariate regression models reveal that for crops grown in the wet season, irrigation is sensitive to distribution and total monsoon rainfall but not to ground or surface water availability. For crops grown in the dry season, total monsoon rainfall matters most, and its effect is sensitive to groundwater availability. The historical estimates from the econometric model are used to calculate future irrigated areas under three different climate model predictions of monsoon climate for the years 2010 - 2050. These projections are then used as input to a physical hydrology model, which quantifies supply of irrigation water from sustainable sources such as rechargeable shallow groundwater, rivers and reservoirs, to unsustainable sources such as non- rechargeable groundwater. We find that the significant variation in monsoon projections lead to very different results. Crops grown in the dry season show particularly divergent trends between model projections, leading to very different groundwater resource requirements.

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

    Science.gov (United States)

    Essaid, Hedeff I; Caldwell, Rodney R

    2017-12-01

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

  19. Jaɨeni Jitoma iaɨyinoɨ ikakɨ = Story of the Orphans of the Sun

    Directory of Open Access Journals (Sweden)

    Hipólito Candre

    2015-10-01

    Full Text Available This text is the Uitoto, Mɨnɨka dialect (with Spanish translation of the story of the Orphans of the Sun, Jitoma and Kechatoma, children of Monairue Jitoma (Sun of the Dawn, from the Uitoto mythology, narrated by Hipólito Candre, Ocaina-Uitoto elder from the Igaraparaná River, in the Colombian Amazon. To listen the original audio recording, see Article Tools / Supplementary files in the sidebar.

  20. Solar flare leaves sun quaking

    Science.gov (United States)

    1998-05-01

    Dr. Alexander G. Kosovichev, a senior research scientist from Stanford University, and Dr. Valentina V. Zharkova from Glasgow (United Kingdom) University found the tell-tale seismic signature in data on the Sun's surface collected by the Michelson Doppler Imager onboard the Solar and Heliospheric Observatory (SOHO) spacecraft immediately following a moderate-sized flare on July 9, 1996. "Although the flare was a moderate one, it still released an immense amount of energy," said Dr. Craig Deforest, a researcher with the SOHO project. "The energy released is equal to completely covering the Earth's continents with a yard of dynamite and detonating it all at once." SOHO is a joint project of the European Space Agency and NASA. The finding is reported in the May 28 issue of the journal Nature, and is the subject of a press conference at the spring meeting of the American Geophysical Union in Boston, Mass., May 27. The solar quake that the science team recorded looks much like ripples spreading from a rock dropped into a pool of water. But over the course of an hour, the solar waves traveled for a distance equal to 10 Earth diameters before fading into the fiery background of the Sun's photosphere. Unlike water ripples that travel outward at a constant velocity, the solar waves accelerated from an initial speed of 22,000 miles per hour to a maximum of 250,000 miles per hour before disappearing. "People have looked for evidence of seismic waves from flares before, but they didn't have a theory so they didn't know where to look," says Kosovichev. Several years ago Kosovichev and Zharkova developed a theory that can explain how a flare, which explodes in space above the Sun's surface, can generate a major seismic wave in the Sun's interior. According to the currently accepted model of solar flares, the primary explosion creates high-energy electrons (electrically charged subatomic particles). These are funneled down into a magnetic flux tube, an invisible tube of magnetic

  1. Seismology of the Wounded Sun

    CERN Document Server

    Cally, Paul S

    2013-01-01

    Active regions are open wounds in the Sun's surface. Seismic oscillations from the interior pass through them into the atmosphere, changing their nature in the process to fast and slow magneto-acoustic waves. The fast waves then partially reflect and partially mode convert to upgoing and downgoing Alfv\\'en waves. The reflected fast and downgoing Alfv\\'en waves then re-enter the interior through the active regions that spawned them, infecting the surface seismology with signatures of the atmosphere. Using numerical simulations of waves in uniform magnetic fields, we calculate the upward acoustic and Alfv\\'enic losses in the atmosphere as functions of field inclination and wave orientation as well as the Time-Distance `travel time' perturbations, and show that they are related. Travel time perturbations relative to quiet Sun can exceed 40 seconds in 1 kG magnetic field. It is concluded that active region seismology is indeed significantly infected by waves leaving and re-entering the interior through magnetic w...

  2. The Sun's New Exotic Neighbour

    Science.gov (United States)

    2006-03-01

    Using ESO's Very Large Telescope in Chile, an international team of researchers [1] discovered a brown dwarf belonging to the 24th closest stellar system to the Sun. Brown dwarfs are intermediate objects that are neither stars nor planets. This object is the third closest brown dwarf to the Earth yet discovered, and one of the coolest, having a temperature of about 750 degrees Celsius. It orbits a very small star at about 4.5 times the mean distance between the Earth and the Sun. Its mass is estimated to be somewhere between 9 and 65 times the mass of Jupiter. At a time when astronomers are peering into the most distant Universe, looking at objects as far as 13 billion light-years away, one may think that our close neighbourhood would be very well known. Not so. Astronomers still find new star-like objects in our immediate vicinity. Using ESO's VLT, they just discovered a brown dwarf companion to the red star SCR 1845-6357, the 36th closest star to the Sun. ESO PR Photo 11/06 ESO PR Photo 11a/06 New Brown Dwarf in the Solar Neighbourhood (Artist's Impression) "This newly found brown dwarf is a valuable object because its distance is well known, allowing us to determine with precision its intrinsic brightness", said team member Markus Kasper (ESO). "Moreover, from its orbital motion, we should be able in a few years to estimate its mass. These properties are vital for understanding the nature of brown dwarfs." To discover this brown dwarf, the team used the high-contrast adaptive optics NACO Simultaneous Differential Imager (SDI [2]) on ESO's Very Large Telescope, an instrument specifically developed to search for extrasolar planets. The SDI camera enhances the ability of the VLT and its adaptive optics system to detect faint companions that would normally be lost in the glare of the primary star. In particular, the SDI camera provides additional, often very useful spectral information which can be used to determine a rough temperature for the object without follow

  3. Present-day irrigation mitigates heat extremes

    Science.gov (United States)

    Thiery, Wim; Davin, Edouard L.; Lawrence, David M.; Hirsch, Annette L.; Hauser, Mathias; Seneviratne, Sonia I.

    2017-02-01

    Irrigation is an essential practice for sustaining global food production and many regional economies. Emerging scientific evidence indicates that irrigation substantially affects mean climate conditions in different regions of the world. Yet how this practice influences climate extremes is currently unknown. Here we use ensemble simulations with the Community Earth System Model to assess the impacts of irrigation on climate extremes. An evaluation of the model performance reveals that irrigation has a small yet overall beneficial effect on the representation of present-day near-surface climate. While the influence of irrigation on annual mean temperatures is limited, we find a large impact on temperature extremes, with a particularly strong cooling during the hottest day of the year (-0.78 K averaged over irrigated land). The strong influence on extremes stems from the timing of irrigation and its influence on land-atmosphere coupling strength. Together these effects result in asymmetric temperature responses, with a more pronounced cooling during hot and/or dry periods. The influence of irrigation is even more pronounced when considering subgrid-scale model output, suggesting that local effects of land management are far more important than previously thought. Our results underline that irrigation has substantially reduced our exposure to hot temperature extremes in the past and highlight the need to account for irrigation in future climate projections.

  4. Landscape Planning of Forest Amelioration on Irrigated Soils

    Directory of Open Access Journals (Sweden)

    Ruleva Olga Vasilyevna

    2015-09-01

    Full Text Available The authors study the landscape program which supposes the formation of land use system aimed at connection of protective shelterbelts to geo-morphological watershed elements, relief, unsimilarity of agricultural territories, adapted to the dynamically balanced state of substance and energy within a landscape. Such approach favors the development of agricultural lands estimation system by means of forest amelioration. It happens due to transformation (reorganization of qualitative and quantitative characteristics of energy mass transfer. Consequently, the radiation, heat, soil, hydrophysical and hydrodynamical processes change as well. So, the area adjoining the protective forest belt is the area of determined processes, while further from the forest belt the space is open for changes of all the characteristics. While estimating lands geoecology, the agroforest landscape was considered as a modification of agricultural landscape forming and functioning under the influence of protective shelterbelts. The landscape unsimilarity of the territory should be taken into account during the optimum organization of irrigated farming. It was made by means of desiphering space photos. According to bioclimatical zonal indications, the dry steppe and desert steppe agrolandscape types have been determined. The irrigated soils of the Volgograd region are located mainly in dry steppe agroforest landscapes on dark-chestnut and chestnut soils within natural ameliorative areas of Privolzhskaya and Ergeninskaya Hills and partly in Zavolzhskaya river delta plain; in semi-desert agroforest landscapes on light-chestnut soils within Zavolzhskaya river delta plain and Sarpinskaya lowlands. The favourable hydrogeological ameliorative situation on the territory of southern Privolzhskaya Hill gives the opportunity to revive the irrigation in the Volgograd region and therefore to increase the productivity and sustainability of agricultural production on a higher scientific

  5. Here comes the sun...; Here comes the sun...

    Energy Technology Data Exchange (ETDEWEB)

    Best, Robert [Centro de Investigacion en Energia (CIE) de la UNAM, Temixco, Morelos (Mexico)

    2010-07-01

    It sounds a bit strange that you can use solar energy to maintain or refrigerate products or spaces below the ambient temperature, because we know that something that makes the sun is heating; but yes indeed, the sun can produce cold, and in addition without polluting, and without consuming conventional energy. In this document are mentioned the various research projects on solar cooling that have been made in the Energy Research Center at the Universidad Nacional Autonoma de Mexico such as the thermo-chemical intermittent refrigerator, the geothermal cooling demonstration system in Mexicali, B.C., the GAX system for air conditioning, the ice producer intermittent solar refrigerator, the continuous solar refrigerator, the refrigeration by ejection-compression. It also mentions the functioning of heat pumps and the process of solar drying applications in agricultural products. [Spanish] Suena un poco extrano que se pueda utilizar la energia solar para mantener o refrigerar productos o espacios por debajo de la temperatura ambiente, ya que sabemos que algo que hace el sol es calentar; pero si, el sol puede producir frio, y ademas sin contaminar y sin consumir energia convencional. En este documento se mencionan las diferentes investigaciones sobre refrigeracion solar que se han realizado en el Centro de Investigacion en Energia de la Universidad Nacional Autonoma de Mexico como el refrigerador termoquimico intermitente, el sistema demostrativo de refrigeracion geotermico en Mexicali, B.C., el sistema GAX para aire acondicionado, el refrigerador solar intermitente productor de hielo, el refrigerador continuo solar, la refrigeracion por eyecto-compresion. Tambien se menciona el funcionamiento de las bombas de calor y el proceso de secado solar de aplicacion en productos agropecuarios.

  6. IRRIGATION OF ORNAMENTAL PLANT NURSERY

    Directory of Open Access Journals (Sweden)

    Eduardo de Aguiar do Couto

    2013-01-01

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

  7. TRIGONOMETRIC SU(N) GAUDIN MODEL

    Institute of Scientific and Technical Information of China (English)

    曹俊鹏; 侯伯宇; 岳瑞宏

    2001-01-01

    In this paper, we obtain the eigenstates and the eigenvalues of the Hamiltonians of the trigonometric SU(N) Gaudin model based on the quasi-classical limit of the trigonometric SU(N) chain with the periodic boundary condition.By using the quantum inverse scattering method, we also obtain the eigenvalues of the generating function of the trigonometric SU(N) Gaudin model.

  8. The summer sun shone round me

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The summer sun shone round me, The folded valley lay In a stream of sun and odour, That sultry summer day. The tall trees stood in the sunlight As still as still could be, But the deep grass sighed and rustled And bowed and beckoned me. The deep grass moved and whispered And bowed and brushed my face. It whis pered in the sunshine: The winter comes apdce.”The summer sun shone round me

  9. Sun awareness in Maltese secondary school students.

    Science.gov (United States)

    Aquilina, S; Gauci, A Amato; Ellul, M; Scerri, L

    2004-11-01

    Studies indicate that reducing exposure to ultraviolet light during childhood and adolescence decreases the risk of skin cancer. From a young age, children need to be educated about the sun's harmful effects on the skin and how best to protect themselves. To help in the design of school-based interventions to raise sun awareness, a school survey was carried out to identify students' stereotypes and misconceptions. A total of 965 students attending Maltese secondary schools in forms 1, 2 and 3 were surveyed in May 2002, using a structured questionnaire designed to examine students' sun-related attitudes and knowledge. A high level of sun awareness among students was demonstrated, with high scores on knowledge of the effects of the sun on the skin, knowledge of skin cancer and knowledge of sun protection. Girls were clearly more knowledgeable than boys. However, of all the students surveyed, 55% thought that a suntan made them look better and 70% thought that their friends would desire a tan. These views were commoner among the older students. Skin type and hair or eye colour had no bearing on attitudes towards tanning or sun-related knowledge. The commonest misconceptions were that 'the sun is bad for your skin only when you get sunburnt' and that 'you cannot get too much sun on a cloudy day'. Deliberate suntanning was more frequently reported by girls than by boys and by students in the higher forms. Attitude change lags behind knowledge. Future school sun awareness interventions need to take into account gender and age differences in students' attitudes and perspectives. They should aim at motivating attitude change and preventive behaviour through consistent and repeated sun-education messages that are supported by a sun-conscious school environment.

  10. Geospatial Dataset of Agricultural Lands in the Upper Colorado River Basin, 2007 - 10

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset represents the extent and spatial distribution of irrigated agricultural lands in the Upper Colorado River Basin for 2007-10. The boundaries in this...

  11. Sun Jingxia Devotes Herself to Nursing Work

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    "I really didn’t expect that at my advanced age, I would be awarded the highest honor in international nursing circles," said Mme. Sun Jingxia, 81, who had just returned from Beijing where she received the Nightingale Medal. Wearing a light yellow suit, with a collar bordered in red, Sun is inhigh spirits, reminding people of the beauty of the setting sun. It is clear that Sun Jingxia has deep feelings as she looks at the medal which shows a relief of Florence Nightingale’s head. She spoke in her usual soft voice but with some excitement, "President Jiang

  12. Groundwater Abstraction for Irrigation and Its Impacts on Low Flows in a Watershed in Northwest Germany

    Directory of Open Access Journals (Sweden)

    Hartmut Wittenberg

    2015-07-01

    Full Text Available Low flows of the Ilmenau River (1434 km2 in northwest Germany have decreased by about 25% over the last 50 years. In the same period, moderate climate changes have taken place and annual groundwater abstractions for sprinkler irrigation have increased by up to 50 hm3 (million m3, with a strong variation due to the respective prevailing weather conditions. Time-series analyses with multiple regression analysis allow detecting and quantifying different influences on low flows. It is also shown that farmers allocate irrigation water volumes carefully according to seasonal precipitation and temperatures. Decline of groundwater levels in summer and the low flow situation are aggravated by the cumulative effect of higher irrigation in drier years. Groundwater recharge and recovery of the water table have been observed subsequently during the winter season.

  13. Effects of Irrigation in India on the Atmospheric Water Budget

    NARCIS (Netherlands)

    Tuinenburg, O.A.; Hutjes, R.W.A.; Stacke, T.; Wiltshire, A.; Lucas-Picher, P.

    2014-01-01

    The effect of large-scale irrigation in India on the moisture budget of the atmosphere was investigated using three regional climate models and one global climate model, all of which performed an irrigated run and a natural run without irrigation. Using a common irrigation map, year-round irrigation

  14. 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

  15. Salinization of the Upper Colorado River - Fingerprinting Geologic Salt Sources

    Science.gov (United States)

    Tuttle, Michele L.W.; Grauch, Richard I.

    2009-01-01

    Salt in the upper Colorado River is of concern for a number of political and socioeconomic reasons. Salinity limits in the 1974 U.S. agreement with Mexico require the United States to deliver Colorado River water of a particular quality to the border. Irrigation of crops, protection of wildlife habitat, and treatment for municipal water along the course of the river also place restrictions on the river's salt content. Most of the salt in the upper Colorado River at Cisco, Utah, comes from interactions of water with rock formations, their derived soil, and alluvium. Half of the salt comes from the Mancos Shale and the Eagle Valley Evaporite. Anthropogenic activities in the river basin (for example, mining, farming, petroleum exploration, and urban development) can greatly accelerate the release of constituents from these geologic materials, thus increasing the salt load of nearby streams and rivers. Evaporative concentration further concentrates these salts in several watersheds where agricultural land is extensively irrigated. Sulfur and oxygen isotopes of sulfate show the greatest promise for fingerprinting the geologic sources of salts to the upper Colorado River and its major tributaries and estimating the relative contribution from each geologic formation. Knowing the salt source, its contribution, and whether the salt is released during natural weathering or during anthropogenic activities, such as irrigation and urban development, will facilitate efforts to lower the salt content of the upper Colorado River.

  16. Occurrence of Escherichia coli in Brassica rapa L. chinensis irrigated with low quality water in urban areas of Morogoro, Tanzania

    DEFF Research Database (Denmark)

    Mhongole, Ofred J.; Mdegela, Robinson H.; Kusiluka, Lughano J. M.

    2016-01-01

    Low quality water has become valuable resource with restricted or unrestricted use in food production depending on its quality. This study has quantified the occurrence of Escherichia coli in Brassica rapa L. chinensis (Chinese cabbage) vegetables and low quality irrigation water. A total of 106...... samples including Chinese cabbage (69) and water (37) were collected. The E. coli were cultured in petri film selective E. coli plates at 44°C. The Chinese cabbage irrigated with river water at Fungafunga area indicated significantly (P... than those irrigated with treated wastewater at Mazimbu 10% (n=48, 0.00-1.36 log cfu/g). The mean counts of E. coli in untreated wastewater ranged from 4.59 to 5.56 log cfu/mL, while in treated wastewater was from 0.54 to 1.05 log cfu/mL and in river water it was 2.40 log cfu/mL. Treated wastewater...

  17. Senegal - Irrigation and Water Resource Management

    Data.gov (United States)

    Millennium Challenge Corporation — IMPAQ: This evaluation report presents findings from the baseline data collected for the Irrigation and Water Resources Management (IWRM) project, which serves as...

  18. 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...

  19. 78 FR 37538 - Idaho Irrigation District; New Sweden Irrigation District; Notice of Preliminary Permit...

    Science.gov (United States)

    2013-06-21

    ... Energy Regulatory Commission Idaho Irrigation District; New Sweden Irrigation District; Notice of... Competing Applications On April 19, 2013, the Idaho and New Sweden Irrigation Districts, filed a joint... Street, Idaho Falls, Idaho 83404; phone: (208) 522-2356. Mr. Louis Thiel, Chairman, New Sweden...

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

    NARCIS (Netherlands)

    Paudel, K.

    2010-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  2. The simulation of cropping pattern to improve the performance of irrigation network in Cau irrigation area

    Science.gov (United States)

    Wahyuningsih, Retno; Rintis Hadiani, RR; Sobriyah

    2017-01-01

    Cau irrigation area located in Madiun district, East Java Province, irrigates 1.232 Ha of land which covers Cau primary channel irrigation network, Wungu Secondary channel irrigation network, and Grape secondary channel irrigation network. The problems in Cau irrigation area are limited availability of water especially during the dry season (planting season II and III) and non-compliance to cropping patterns. The evaluation of irrigation system performance of Cau irrigation area needs to be done in order to know how far the irrigation system performance is, especially based on planting productivity aspect. The improvement of irrigation network performance through cropping pattern optimization is based on the increase of water necessity fulfillment (k factor), the realization of planting area and rice productivity. The research method of irrigation system performance is by analyzing the secondary data based on the Regulation of Ministry of Public Work and State Minister for Public Housing Number: 12/PRT/M/2015. The analysis of water necessity fulfillment (k factor) uses Public Work Plan Criteria Method. The performance level of planting productivity aspect in existing condition is 87.10%, alternative 1 is 93.90% dan alternative 2 is 96.90%. It means that the performance of the irrigation network from productivity aspect increases 6.80% for alternative 1 and 9.80% for alternative 2.

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

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    NARCIS (Netherlands)

    Paudel, K.

    2010-01-01

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

  5. 77 FR 16828 - Turlock Irrigation District, & Modesto Irrigation District; Notice of Dispute Resolution Process...

    Science.gov (United States)

    2012-03-22

    ... Energy Regulatory Commission Turlock Irrigation District, & Modesto Irrigation District; Notice of... and the Modesto Irrigation District (collectively, the Districts), are co-licensees for the Don Pedro... Steelhead Full Life-Cycle Population Models; and Request 9--Effects of the Project and Related Facilities on...

  6. Microbial Water Pollution of Drin River in Scutary Area, Albania

    Directory of Open Access Journals (Sweden)

    LINDITA BUSHATI

    2014-06-01

    Full Text Available Black Drin River joining White Drin and some other small rivers form the longest river of Albania, Drin River, 335 Km long. Drin has two distributaries, one of which empties directly into Adriatic Sea and the other one into Buna river, in Scutary (Shkoder. The Drin area is beautiful and very important for the Albanian economy, for the electricity and has a large agriculture activity as well. Unfortunately mismanagement of agricultural practices and the discharge of industrial and urban wastes into the river are causing a high pollution. River conservation is threatened by pollution. Drin river water is used by people for fishing, swimming and irrigation of plants and the pollution of this river is a problematic issue in environment and human health. We monitored microbial and chemical water pollution of Scutary area of Drin, where Drin goes into Bojana, during 2012-2013 and a high water pollution level was recorded.

  7. Hydrological, ecological, land use, economic, and sociocultural evidence for resilience of traditional irrigation communities in New Mexico, USA

    Science.gov (United States)

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

    2014-02-01

    Southwestern US irrigated landscapes are facing upheaval due to climate change-induced water scarcity and economic change-induced land use conversion. Clues to community longevity are found in the traditionally irrigated valleys of northern New Mexico. Human systems have interacted with hydrologic processes over the last 400 yr in river fed irrigated valleys to create linked systems. In this study, we asked if concurrent data from multiple disciplines show that human adapted hydrologic and socioeconomic systems have created conditions for resilience. We identify and describe several areas of resilience: hydrological, ecological, land use, economic, and sociocultural. We found that there are multiple hydrologic benefits of the water seepage from the traditional irrigation systems; it recharges groundwater that recharges rivers, supports threatened biodiversity by maintaining riparian vegetation, and ameliorates impacts of climate change by prolonging streamflow hydrographs. In terms of land use and economics, place-based adaptability manifests itself in transformations of irrigation infrastructure and specific animal and crop systems; as grazing has diminished over time on public land watersheds, it has increased on irrigated valley pastures while outside income allows irrigators to retain their land. Sociocultural evidence shows that traditional local knowledge about the hydrosocial cycle of acequia operations is a key factor in acequia resilience. When irrigators are confronted with unexpected disturbances or changing climate that affect water supply, they adapt specific practices while maintaining community cohesion. Our ongoing work will quantify the multiple disciplinary components of these systems, translate them into a common language of causal loop diagrams, and model future scenarios to identify thresholds and tipping points of sustainability. Early indications are that these systems are not immune to upheaval, but have astonishing resilience.

  8. 灌溉水矿化度对玛纳斯流域棉花生长影响的试验研究%Experimental Study on the Impacts of the Irrigation Water Salinity on Cotton Growth in Manas River Oasis, Xinjiang

    Institute of Scientific and Technical Information of China (English)

    杨传杰; 罗毅; 孙林; 甘容; 吴娜; 张艳; 阿布都外力·吉力力

    2012-01-01

    合理利用咸水资源对缓解干旱区绿洲农业用水矛盾有重要意义。本文于2010年和2011年在石河子大学节水灌溉试验站研究了矿化度为0.87、2、3、4、6、8g/L的咸水对土壤水盐动态和棉花生长及产量的影响。结果表明,咸水灌溉导致土壤剖面持续积盐,棉花叶面积指数减小,干物质积累减少、产量下降;灌溉水矿化度每提高1g/L,产量降低约391kg/hm2;土壤根系层(0~60cm)可溶性盐浓度每升高1g/L,产量降低约861kg/hm2。在灌溉水矿化度2g/L情况下,100cm土层盐分最大累积率2010年为113%,2011年为26%,呈下降趋势,棉花生长、干物质积累及产量受影响较小,可作为该区咸水利用调控参考阈值,指导农业生产。%Oasis agriculture in northwest China has long been confronted with water resources shortage. Groundwater is abundant but it is usually saline water with salinity ranging from 1g/L to 5g/L or more. However, saline water is an important potential water source for oasis irrigation so the reasonable use of that salty water may play a vital role in easing the contradiction of oasis agricultural water in arid region. Field tests have been carried out to investigate the potential impacts of saline water with salinity levels of 0.87g/L, 2g/L, 3g/L, 4g/L, 6g/L, and 8g/L respectively on the trends of salt in soil water and cotton growth and its yield in the Manas River oasis in 2010 and 2011 growth seasons. Besides, soil salinity, cotton stems, leaves and balls were sampled in situ and then measured in the laboratory at weekly intervals. The results indicate that: 1) Salt accumulation increases with the salinity of irrigation water, and only a minor accumulation is found in case of water salinity of 2g/L or less; 2) The saline water has impacts on the growth and biomass accumulation of the cotton plants’stem, leaf, and especially the ball, and as a result, reduces the yield; 3)The higher the water salinity is, the

  9. Regina vs Hubbs: Determining the Sun's Position

    CERN Document Server

    Samra, Raminder Singh

    2012-01-01

    Here I determined the Sun's position as an expert witness for crown counsel. From my calculations I found the Sun's location in the sky was such that it could not impede the driver's vision, as a result it could not have been the reason for the accused to be involved in a motor vehicle accident.

  10. 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

  11. Irrigation as an historical climate forcing

    Science.gov (United States)

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

    2015-03-01

    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

  12. Assessing Potential Land Suitability for Surface Irrigation using Groundwater in Ethiopia

    Science.gov (United States)

    Worqlul, A. W.; Jeong, J.; Osorio, J.; Gerik, T.; Yihun, D.; Srinivan, R.; Clark, N.

    2016-12-01

    Although Ethiopia has large land areas that can potentially be developed for surface irrigation, only a fraction of the potential available land has been utilized. This paper presents evaluation of the potential lands in Ethiopia that are suitable for irrigation using groundwater. The suitable land was identified using GIS-based Multi-Criteria Evaluation (MCE) techniques applying a GIS model. The factors used were identified from literature and from experts in the region. Factors considered includes physical land features (land use, soil and slope), climate characteristics (rainfall and evapotranspiration), and market access (proximity to roads and access to market). Factors were weighted using a pair-wise comparison matrix, reclassified, and overlaid to identify the suitable areas for groundwater irrigation at 1 km grid. Groundwater data from the British Geological Survey were used to estimate potential groundwater availability and analyze the irrigation potential for dominant crops. Simulated output from SWAT could be used in areas where data is not available. Result indicates that approximately 6.0 million ha of land in Ethiopia is suitable for surface irrigation. A large portion of this suitable land is located in the Abbay, Rift Valley, Omo Ghibe, and Awash River basins, which all also have shallow groundwater access (< 20 m from the surface). The comparison between available groundwater and total crop water requirements indicated that current groundwater resources in the basins are not capable of irrigating all suitable land independently, but groundwater resources are a good option for supplementing current surface water resources in many regions. The study indicated that only 8 % of the suitable land could be irrigated with the groundwater within the grid.

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

    Directory of Open Access Journals (Sweden)

    H. Biemans

    2015-08-01

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

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

    Science.gov (United States)

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

    2016-05-01

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

  15. Impact of agricultural practices on groundwater quality in intensive irrigated area of Chtouka-Massa, Morocco.

    Science.gov (United States)

    Malki, Mouna; Bouchaou, Lhoussaine; Hirich, Abdelaziz; Ait Brahim, Yassine; Choukr-Allah, Redouane

    2017-01-01

    The Plio-Quaternary aquifer of Chtouka is located in Southwestern of Morocco. The intensive agricultural activity in Chtouka basin requires the mobilization of 94% of fresh water resources for irrigation. This overexploitation, along with the succession of drought years, sea water intrusion and various sources of pollution, affected the quality and availability of groundwater resources. Several sampling campaigns were carried out in different sites of the study area in order to investigate the spatial variation of groundwater quality. The temporal evolution of groundwater level shows that the water table was subjected to a gradual decline during the last decade, indicating an intensive exploitation mainly in irrigated areas. In the Southern part around Belfaa and the irrigated area along Massa River, nitrate concentrations exceed 50mg/L, which is the threshold set by the World Health Organization, while in the northern part around Biougra and Ait Amira, the nitrate concentration is mostly below 50mg/L indicating a relative good groundwater quality. This finding can be explained by the improvement of agricultural practices, particularly the conversion of flood and sprinkler irrigation to drip irrigation (80% of the total irrigated area) in most of the developed farms in this part of the study area. Moreover, the exploitation of groundwater from the deep aquifer, due to the increasing water demand in the region, can also explain the low chemical concentrations since the deep aquifer is not affected by anthropogenic pollutants or marine intrusion. Stable isotopes ((18)O and (2)H) highlight the different origins of groundwater, indicating the complexity of the aquifer system path flows, which is attributable to the intensive exploitation and irrigation water return. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2015-08-01

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

  17. Influence of mid-latitude circulation on upper Indus basin precipitation: the explicit role of irrigation

    Science.gov (United States)

    Saeed, Fahad; Hagemann, Stefan; Saeed, Sajjad; Jacob, Daniela

    2013-01-01

    Since much of the flow of the Indus River originates in the Himalayas, Karakoram and Hindu Kush Mountains, an understanding of weather characteristics leading to precipitation over the region is essential for water resources management. This study examines the influence of upper level mid-latitude circulation on the summer precipitation over upper Indus basin (UIB). Using reanalysis data, a geopotential height index (GH) is defined at 200 hPa over central Asia, which has a significant correlation with the precipitation over UIB. GH has also shown significant correlation with the heat low (over Iran and Afghanistan and adjoining Pakistan), easterly shear of zonal winds (associated with central Asian high) and evapotranspiration (over UIB). It is argued that the geopotential height index has the potential to serve as a precursor for the precipitation over UIB. In order to assess the influence of irrigation on precipitation over UIB, a simplified irrigation scheme has been developed and applied to the regional climate model REMO. It has been shown that both versions of REMO (with and without irrigation) show significant correlations of GH with easterly wind shear and heat low. However contrary to reanalysis and the REMO version with irrigation, the REMO version without irrigation does not show any correlation between GH index and evapotranspiration as well as between geopotential height and precipitation over UIB, which is further confirmed by the quantitative analysis of extreme precipitation events over UIB. It is concluded that although atmospheric moisture over coastal Arabian sea region, triggered by wind shear and advected northward due to heat low, also contribute to the UIB precipitation. However for the availability of necessary moisture for precipitation over UIB, the major role is played by the evapotranspiration of water from irrigation. From the results it may also be inferred that the representation of irrigated water in climate models is unavoidable for

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

    Institute of Scientific and Technical Information of China (English)

    Lina SUN; Xiao-e YANG; Wen-qing WANG; Li MA; Su CHEN

    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 con- tamination 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.

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

    Science.gov (United States)

    Fadlillah, Lintang N; Widyastuti, M

    2016-08-01

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

  20. Mitigation of climate change impacts by hydrologic and cultural components of traditional acequia irrigation systems

    Science.gov (United States)

    Fernald, A.

    2009-12-01

    In northern New Mexico and other physiographically similar semi-arid settings worldwide, traditional irrigation systems divert snowmelt runoff from streams for distribution to valley croplands. This field hydrology and culture study is taking place in three New Mexico watersheds. Ongoing measurements show that seepage to groundwater and subsequent stream recharge from subsurface return flows effectively reduce spring runoff peaks and augment summer baseflow. This retransmission function of traditional acequia irrigated valleys is important for downstream users, particularly in the face of changing climate with projected earlier snowmelt and increased rain. Preliminary evaluations of the community irrigation management structure show high adaptability to climate variation. Water is partitioned to individual users based on water availability, with more water for all in wet years and less for all in dry years. Irrigation water seepage has additional benefits: water quality improvement, wildlife habitat creation, riparian vegetation support, and aesthetic enhancement. Community cohesion and longevity are supported by hydrologic and cultural aspects of the irrigation systems. Lessons learned from these systems promise a window into techniques for sustainable management of linked watersheds and river valleys under future climate change scenarios.

  1. Study on Intermittent Irrigation for Paddy Rice:I.Water Use Efficiency

    Institute of Scientific and Technical Information of China (English)

    LUJUN; T.HIRASAWA

    2001-01-01

    A field experiment was conducted in a well-puddled paddy field developed on the Tama River alluvial soil in the Farm of Tokyo University of Agriculture and Technology,Japan,to study the effect of intermittent irrigation on water use efficiency of paddy rice,Four treatments were arranged with 2 replicates:continuous flooding irrigation treatments(CFI),and three intermittent irrigation treatments Ⅱ-0,Ⅱ-1 and Ⅱ-2,in which plants were re-irrigated when the soil water potential.fell below 0,-10,and -20 kPa,respectively,at soil depth of about 5 cm,Water consumption wa lower in treatment Ⅱ-0 than in treatment CFI because the percolation rate was reduced by the reduction in the hydraulic head of ponded water .Intermittent irrigation led to soil repeated shrinking and swelling in Ⅱ-1 and Ⅱ-2 plots and ,therefore,soil cracks developed rapidly.Since they became the major routes of water percolation,the soil cracks increased waer consumption in treatments Ⅱ-1 and Ⅱ-2.there were no significant differenes in dry matter production and grain yields between treatment Ⅱ-0 and treatment CFI,but the dry matter production and grain yields in treatments Ⅱ-0 and CFI were significantly higher than those in treatments Ⅱ-1 and Ⅱ-2,Therefore,the eater use efficiency in the treatments was in the order of Ⅱ-0>CFI>Ⅱ-2>Ⅱ-1.

  2. Mitochondrial DNA deletion percentage in sun exposed and non sun exposed skin.

    Science.gov (United States)

    Powers, Julia M; Murphy, Gillian; Ralph, Nikki; O'Gorman, Susan M; Murphy, James E J

    2016-12-01

    The percentages of mitochondrial genomes carrying the mtDNA(3895) and the mtDNA(4977) (common) deletion were quantified in sun exposed and non sun exposed skin biopsies, for five cohorts of patients varying either in sun exposure profile, age or skin cancer status. Non-melanoma skin cancer diagnoses are rising in Ireland and worldwide [12] but most risk prediction is based on subjective visual estimations of sun exposure history. A quantitative objective test for pre-neoplastic markers may result in better adherence to sun protective behaviours. Mitochondrial DNA (mtDNA) is known to be subject to the loss of a significant proportion of specific sections of genetic code due to exposure to ultraviolet light in sunlight. Although one such deletion has been deemed more sensitive, another, called the mtDNA(4977) or common deletion, has proved to be a more useful indicator of possible risk in this study. Quantitative molecular analysis was carried out to determine the percentage of genomes carrying the deletion using non sun exposed and sun exposed skin biopsies in cohorts of patients with high or low sun exposure profiles and two high exposure groups undergoing treatment for NMSC. Results indicate that mtDNA deletions correlate to sun exposure; in groups with high sun exposure habits a significant increase in deletion number in exposed over non sun exposed skin occurred. An increase in deletion percentage was also seen in older cohorts compared to the younger group. The mtDNA(3895) deletion was detected in small amounts in exposed skin of many patients, the mtDNA(4977) common deletion, although present to some extent in non sun exposed skin, is suggested to be the more reliable and easily detected marker. In all cohorts except the younger group with relatively lower sun exposure, the mtDNA(4977) deletion was more frequent in sun exposed skin samples compared to non-sun exposed skin.

  3. Gravitational Lensing Characteristics of the Transparent Sun

    CERN Document Server

    Patla, Bijunath

    2007-01-01

    The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent Standard Solar Model (SSM) data. The Sun's minimum focal length is computed to a refined accuracy of 23.5 +/- 0.1 AU, just beyond the orbit of Uranus. The Sun creates a single image of a distant point source visible to observers inside this minimum focal length and to observers sufficiently removed from the line connecting the source through the Sun's center. Regions of space are mapped where three images of a distant point source are created, along with their associated magnifications. Solar caustics, critical curves, and Einstein rings are computed and discussed. Extremely high gravitational lens magnifications exist for observers situated so that an angularly small, unlensed source appears near a three-image caustic. Types of radiations that might undergo significant solar lens magnifications as they can traverse the core of the Sun, including neutrinos and gravitational radiation, are discusse...

  4. Vibration Based Sun Gear Damage Detection

    Science.gov (United States)

    Hood, Adrian; LaBerge, Kelsen; Lewicki, David; Pines, Darryll

    2013-01-01

    Seeded fault experiments were conducted on the planetary stage of an OH-58C helicopter transmission. Two vibration based methods are discussed that isolate the dynamics of the sun gear from that of the planet gears, bearings, input spiral bevel stage, and other components in and around the gearbox. Three damaged sun gears: two spalled and one cracked, serve as the focus of this current work. A non-sequential vibration separation algorithm was developed and the resulting signals analyzed. The second method uses only the time synchronously averaged data but takes advantage of the signal/source mapping required for vibration separation. Both algorithms were successful in identifying the spall damage. Sun gear damage was confirmed by the presence of sun mesh groups. The sun tooth crack condition was inconclusive.

  5. Sun Safe Mode Controller Design for LADEE

    Science.gov (United States)

    Fusco, Jesse C.; Swei, Sean S. M.; Nakamura, Robert H.

    2015-01-01

    This paper presents the development of sun safe controllers which are designed to keep the spacecraft power positive and thermally balanced in the event an anomaly is detected. Employed by NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE), the controllers utilize the measured sun vector and the spacecraft body rates for feedback control. To improve the accuracy of sun vector estimation, the least square minimization approach is applied to process the sensor data, which is proven to be effective and accurate. To validate the controllers, the LADEE spacecraft model engaging the sun safe mode was first simulated and then compared with the actual LADEE orbital fight data. The results demonstrated the applicability of the proposed sun safe controllers.

  6. Social and ecological aspects of the water resources management of the transboundary rivers of Central Asia

    Science.gov (United States)

    Normatov, P.

    2014-09-01

    The Zeravshan River is a transboundary river whose water is mainly used for irrigation of agricultural lands of the Republic of Uzbekistan. Sufficiently rich hydropower resources in upstream of the Zeravshan River characterize the Republic of Tajikistan. Continuous monitoring of water resources condition is necessary for planning the development of this area taking into account hydropower production and irrigation needs. Water quality of Zeravshan River is currently one of the main problems in the relationship between the Republics of Uzbekistan and Tajikistan, and it frequently triggers conflict situations between the two countries. In most cases, the problem of water quality of the Zeravshan River is related to river pollution by wastewater of the Anzob Mountain-concentrating Industrial Complex (AMCC) in Tajikistan. In this paper results of research of chemical and bacteriological composition of the Zeravshan River waters are presented. The minimum impact of AMCC on quality of water of the river was experimentally established.

  7. Study of Microbial Diversity and the Soil Enzyme Activity in Different Salinized Soil in Ningxia Yellow River Irrigation Region%宁夏引黄灌区不同盐化程度土壤酶活性及微生物多样性研究

    Institute of Scientific and Technical Information of China (English)

    李凤霞; 王学琴; 郭永忠; 许兴

    2013-01-01

    In order to know the effects of different degradation degree of salinized soil on microbial diversity and soil enzyme activity in Ningxia irrigation area of Yellow River, soil microbial diversity and soil enzyme activity were studied in different degree of salinized using biolog microbial identification system, colorimetry and titration in Ningxia Yellow River Irrigation. The results showed that soil microbial community diversity decreased with the saline degree in ecreased. Soil catalase, invertase, alkaline phosphatase and urease activity tend to decrease with the increase of salt degree. The seasonal variation of soil enzyme activity was not exactly the same, and fluctuateed in different layers of soil. Converting enzyme and alkaline phosphatase activities in 0-20 cm soil performanced in the order of September>August>June, catalase and alkaline phosphatase activities in 20-40 cm soil presented as the sequence of June>August>September. There was a significant positive correlation (P<0.05) between different salinization degree soil and converting enzyme, alkaline phosphatase activity, there was a very significant positive correlation (P<0.01) between soil microbial diversity and converting enzyme, alkaline phosphatase, catalase activity, and was a significant positive correlation (P<0.05) between soil microbial diversity and different soil salinization degree, soil urease activity. These results suggested that the relationships between soil enzyme activity and soil salinization degree were closely related, and the soil converting enzyme, alkaline phosphatase and microbial diversity can be used as biological indicators for the evaluation of saline-alkali soil degradation degree and soil fertility.%为了掌握宁夏引黄灌区盐碱地盐化土壤退化程度对微生物多样性及土壤酶活性的影响及其变化规律,采用Biolog微生物鉴定系统、比色法及滴定法对宁夏引黄灌区不同程度盐化土壤微生物多样性和土壤酶活性进

  8. Transforming River Basin Management In South Africa: Lessons from the Lower Komati River

    NARCIS (Netherlands)

    Waalewijn, P.; Wester, P.; Straaten, van K.

    2005-01-01

    This paper analyzes the transformation of river basin management in South Africa by focusing on the political processes involved in the creation of new water management bodies and irrigation infrastructure in the Lower Komati sub-basin. Institutional reform is described and analyzed in terms of the

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

    Directory of Open Access Journals (Sweden)

    A. D. Chukalla

    2015-07-01

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

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

    Science.gov (United States)

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

    2015-12-01

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

  11. Identifying the potential for irrigation development in Mozambique: Capitalizing on the drivers behind farmer-led irrigation expansion

    NARCIS (Netherlands)

    Beekman, P.W.; Veldwisch, G.J.A.; Bolding, J.A.

    2014-01-01

    Smallholder irrigation in Central Mozambique predominantly takes place in an informal setting. This renders these smallholders and their activities invisible for policy purposes. Identification efforts of smallholder irrigation as well as the potential for new irrigation development are often the

  12. 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

  13. A scintigraphic study of colostomy irrigation

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-09-01

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

  14. Syringe irrigation: blending endodontics and fluid dynamics

    NARCIS (Netherlands)

    C. Boutsioukis; L.W.M. van der Sluis

    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

  15. 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

  16. Using Automation to Improve Surface Irrigation Management

    Science.gov (United States)

    In the Lower Mississippi Water Resource Area (WRA 08), also called the Mid-South, 2 million ha of cropland (80% of the irrigated farmland) employ surface irrigation, almost equally divided between furrow (52%) and controlled flooding (48%). Because Mid-South farmers experience less-than-optimal surf...

  17. Soil Enzyme Activities with Greenhouse Subsurface Irrigation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-Long; WANG Yao-Sheng

    2006-01-01

    Various environmental conditions determine soil enzyme activities, which are important indicators for changes of soil microbial activity, soil fertility, and land quality. The effect of subsurface irrigation scheduling on activities of three soil enzymes (phosphatase, urease, and catalase) was studied at five depths (0-10, 10-20, 20-30, 30-40, and 40-60 cm) of a tomato greenhouse soil. Irrigation was scheduled when soil water condition reached the maximum allowable depletion(MAD) designed for different treatments (-10, -16, -25, -40, and -63 kPa). Results showed that soil enzyme activities had significant responses to the irrigation scheduling during the period of subsurface irrigation. The neutral phosphatase activity and the catalase activity were found to generally increase with more frequent irrigation (MAD of -10 and -16kPa). This suggested that a higher level of water content favored an increase in activity of these two enzymes. In contrast,the urease activity decreased under irrigation, with less effect for MAD of -40 and -63 kPa. This implied that relatively wet soil conditions were conducive to retention of urea N, but relatively dry soil conditions could result in increasing loss of urea N. Further, this study revealed that soil enzyme activities could be alternative natural bio-sensors for the effect of irrigation on soil biochemical reactions and could help optimize irrigation management of greenhouse crop production.

  18. CROP DENSITY AND IRRIGATION WITH SALINE WATER

    OpenAIRE

    Feinerman, Eli

    1983-01-01

    The economic implications of plant density for irrigation water use under saline conditions are investigated, utilizing the involved physical and biological relationships. The analysis considers a single crop and is applied to cotton data. The results suggest that treating plant density as an endogenous control variable has substantial impact on profits and the optimal quantities and qualities of the applied irrigation water.

  19. Tomato Root Response to Subsurface Drip Irrigation

    Institute of Scientific and Technical Information of China (English)

    ZHUGE Yu-Ping; ZHANG Xu-Dong; ZHANG Yu-Long; LI Jun; YANG Li-Juan; HUANG Yi; LIU Ming-Da

    2004-01-01

    Four depth treatments of subsurface drip irrigation pipes were designated as 1) at 20,2) 30 and 3) 40 cm depths all with a drip-proof flumes underneath,and 4) at 30 cm without a drip-proof flume to investigate the responses of a tomato root system to different technical parameters of subsurface drip irrigation in a glass greenhouse,to evaluate tomato growth as affected by subsurface drip irrigation,and to develop an integrated subsurface drip irrigation method for optimal tomato yield and water use in a glass greenhouse. Tomato seedlings were planted above the subsurface drip irrigation pipe. Most of the tomato roots in treatment 1 were found in the top 0-20 cm soil depth with weak root activity but with yield and water use efficiency (WUE) significantly less (P ---- 0.05) than treatment 2; root activity and tomato yield were significantly higher (P = 0.05) with treatment 3 compared to treatment 1; and with treatment 2 the tomato roots and shoots grew harmoniously with root activity,nutrient uptake,tomato yield and WUE significantly higher (P= 0.05) or as high as the other treatments. These findings suggested that subsurface drip irrigation with pipes at 30 cm depth with a drip-proof flume placed underneath was best for tomato production in greenhouses. In addition,the irrigation interval should be about 7-8 days and the irrigation rate should be set to 225 m3 ha-1 per event.

  20. Water Resources Impacts on Tribal Irrigation Projects

    Science.gov (United States)

    Minihane, M.

    2015-12-01

    The Bureau of Indian Affairs (BIA) Branch of Irrigation and Power provides oversight and technical support to select irrigation projects and systems on tribal lands. The BIA provides operations and maintenance support for 16 irrigation systems. To make the best use of limited resources, the BIA must incorporate climate change impacts on hydrology and water management for these irrigation systems in the coming decades. The 16 irrigation projects discussed here are divided into three climatological regions: the Pacific Northwest Region, the Greater Rocky Mountain Region, and the Western, Southwest, & Navajo Region. Significant climate projections that impact irrigation systems in one or more of these regions include increased temperatures and evaporative demand, earlier snowmelt and runoff, an increase in floods, an increase in heavy precipitation events, an increase in the frequency and intensity of droughts, and declining water supplies. Some irrigation projects are particularly vulnerable to these climate impacts because they are in already water-stressed areas or areas in which water resources are over-allocated. Other irrigation projects will have to adjust their storage and water management strategies to accommodate changes in the timing of streamflow. Overall, though, the BIA will be better able to assist tribal nations by incorporating expected climate impacts into their water resources management practices.

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    without caps from a height >1 m. CONCLUSION: Simple, cheap and easily adoptable irrigation methods have great potential to reduce crop contamination in low-income areas. When used in combination with other on-farm and post-harvest risk reduction measures, these will help to comprehensively reduce public......OBJECTIVE: To assess the effectiveness of simple irrigation methods such as drip irrigation kits, furrow irrigation and use of watering cans in reducing contamination of lettuce irrigated with polluted water in urban farming in Ghana. METHODS: Trials on drip kits, furrow irrigation and watering...... cans were conducted with urban vegetable farmers. Trials were arranged in a completely randomised block design with each plot having all three irrigation methods tested. This was conducted in both dry and wet seasons. Three hundred and ninety-six lettuce, 72 soil, 15 poultry manure and 32 water samples...

  2. Reclaimed Water for Turfgrass Irrigation

    Directory of Open Access Journals (Sweden)

    Xunzhong Zhang

    2010-09-01

    Full Text Available Sustainable irrigation of turfgrass grown on coarse-textured soils with reclaimed water must avoid detrimental effects of soluble salts on plant growth and soil quality and groundwater enrichment of nitrogen (N and phosphorus (P. The purpose of this study was (1 to investigate the effects of irrigating with municipal reclaimed water containing higher concentrations of soluble salts than potable water on turfgrass growth and quality and (2 to compare the effects of reclaimed and potable water on turfgrass assimilation and leaching of N and P. A sand-based medium plumbed to supply potable and reclaimed water and instrumented with lysimeters to collect leachate was planted with hybrid bermudagrass (Cynodon dactylon x Cynodon transvaalensis var. Tifsport and creeping bentgrass (Agrostis stolonifera var. L-93. Both species produced high quality turfgrass with the reclaimed water. Although both grasses are moderately or highly salt tolerant when fully established, the bermudagrass growth and quality were reduced by the reclaimed water upon breaking dormancy, and its N use during this period was reduced. Continuous use of reclaimed water of the quality used in the study poses a potential soil Na accumulation problem. Both turfgrasses assimilated high amounts of N and P with minimal potential losses to groundwater.

  3. Integrated assessment of the effects of dams on irrigation sustainability in a data scarce watershed

    Science.gov (United States)

    Yoshida, T.; Masumoto, T.; Kudo, R.

    2014-12-01

    Several development projects are currently under way in developing countries to meet growing demand for water and energy. However, due to the lack of the hydro-meteorological data, some projects were conducted without rigorous check of water balance and the potential changes in the flow regime likely to be induced by reservoirs, and their implications for irrigation projects and ecosystems. To cope with this issues, we carried out analysis by using a hydrological model and quasi-observed rainfall data. A distributed water circulation model was introduced as a tool to implement the analysis. Given daily meteorological data, the model calculates spatial distribution of surface runoff, evapotranspiration, river flow and water demand. In addition, it represents operation of water use facilities, and return flow from irrigated areas. We performed a case study in the Pursat River Basin in Cambodia, where multiple projects are ongoing. We first calculated river discharge with observed rain data and calibrated it. Next, we performed a water balance analysis of the basin using the compiled model with 7 years of rainfall data. Because 20-30 years of data is generally required for water resources planning, we thus prepared 25 years of data by using a climate model with a statistically corrected bias. We determined a reference year for irrigation planning from the long-term data such that annual precipitation of 5-year return period. We selected a scenario for irrigated areas from the Water Balance Study Report (JICA, 2013) to project the future water demand, and checked the water balance under no-dam conditions. The results revealed that water supply was more than adequate to meet water demand in the reference year. We finally incorporated the future dam operations into the calculations and evaluated the impact of the dams on river flows and irrigation projects. Even under the changed flow regimes, the water balance was satisfied in the reference year. However, river flows

  4. Irrigation and Instream Management under Drought Conditions using Probabilistic Constraints

    Science.gov (United States)

    Oviedo-Salcedo, D. M.; Cai, X.; Valocchi, A. J.

    2009-12-01

    It is well-known that river-aquifer flux exchange may be an important control on low flow condition in a stream. Moreover, the connections between streams and underlying formations can be spatially variable due to geological heterogeneity and landscape topography. For example, during drought seasons, farming activities may induce critical peak pumping rates to supply irrigation water needs for crops, and this leads to increased concerns about reductions in baseflow and adverse impacts upon riverine ecosystems. Quantitative management of the subsurface water resources is a required key component in this particular human-nature interaction system to evaluate the tradeoffs between irrigation for agriculture and the ecosystems low flow requirements. This work presents an optimization scheme developed upon the systems reliability-based design optimization -SRBDO- analysis, which accounts for prescribed probabilistic constraint evaluation. This approach can provide optimal solutions in the presence of uncertainty with a higher level of confidence. In addition, the proposed methodology quantifies and controls the risk of failure. SRBDO have been developed in the aerospace industry and extensively applied in the field of structural engineering, but has only seen limited application in the field of hydrology. SRBDO uses probability theory to model uncertainty and to determine the probability of failure by solving a mathematical nonlinear programming problem. Furthermore, the reliability-based design optimization provides a complete and detailed insight of the relative importance of each random variable involved in the application, in this case the surface -groundwater coupled system. Importance measures and sensitivity analyses of both, random variables and probability distribution function parameters are integral components of the system reliability analysis. Therefore, with this methodology it is possible to assess the contribution of each uncertain variable on the total

  5. [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.

  6. Historical influence of irrigation on climate extremes

    Science.gov (United States)

    Thiery, Wim; Davin, Edouard L.; Lawrence, Dave; Hauser, Mathias; Seneviratne, Sonia I.

    2016-04-01

    Land irrigation is an essential practice sustaining global food production and many regional economies. During the last decades, irrigation amounts have been growing rapidly. Emerging scientific evidence indicates that land irrigation substantially affects mean climate conditions in different regions of the world. However, a thorough understanding of the impact of irrigation on extreme climatic conditions, such as heat waves, droughts or intense precipitation, is currently still lacking. In this context, we aim to assess the historical influence of irrigation on the occurrence of climate extremes. To this end, two simulations are conducted over the period 1910-2010 with a state-of-the-art global climate model (the Community Earth System Model, CESM): a control simulation including all major anthropogenic and natural external forcings except for irrigation and a second experiment with transient irrigation enabled. The two simulations are evaluated for their ability to represent (i) hot, dry and wet extremes using the HadEX2 and ERA-Interim datasets as a reference, and (ii) latent heat fluxes using LandFlux-EVAL. Assuming a linear combination of climatic responses to different forcings, the difference between both experiments approximates the influence of irrigation. We will analyse the impact of irrigation on a number of climate indices reflecting the intensity and duration of heat waves. Thereby, particular attention is given to the role of soil moisture changes in modulating climate extremes. Furthermore, the contribution of individual biogeophysical processes to the total impact of irrigation on hot extremes is quantified by application of a surface energy balance decomposition technique to the 90th and 99th percentile surface temperature changes.

  7. The Sun and How to Observe It

    CERN Document Server

    Jenkins, Jamey L

    2009-01-01

    Without the Sun, all life on Earth would perish. But what exactly do we know about this star that lights, heats, and powers Earth? Actually, we know quite a lot, thanks mainly to a host of eager solar observers. Looking directly at the Sun is EXTREMELY hazardous. But many astronomers, both professional and amateur, have found ways to view the Sun safely to learn about it. You, too, can view the Sun in all of its glorious detail. Some of the newest, most exciting telescopes on the market are affordable to amateur astronomers or even just curious sky watchers, and with this guide to what the Sun has to offer, including sunspots, prominences, and flares, plus reviews of the latest instruments for seeing and capturing images of the Sun, you can contribute to humankind’s knowledge of this immense ball of glowing gases that gives us all life. For a complete guide to Sun viewing, see also Total Solar Eclipses and How to Observe Them (2007) by Martin Mobberley in this same series.

  8. Sun-synchronous satellite orbit determination

    Science.gov (United States)

    Ma, Der-Ming; Zhai, Shen-You

    2004-02-01

    The linearized dynamic equations used for on-board orbit determination of Sun-synchronous satellite are derived. Sun-synchronous orbits are orbits with the secular rate of the right ascension of the ascending node equal to the right ascension rate of the mean sun. Therefore the orbit is no more a closed circle but a tight helix about the Earth. In the paper, instead of treating the orbit as a closed circle, the actual helix orbit is taken as nominal trajectory. The details of the linearized equations of motion for the satellite in the Sun-synchronous orbit are derived. The linearized equations are obtained by perturbing the Keplerian motion with the J2 correction and the effect of sun's attraction being neglected. Combined with the GPS navigation equations, the Kalman filter formulation is given. The particular application considered is the circular Sun-synchronous orbit with the altitude of 800 km and inclination of 98.6°. The numerical example simulated by MATLAB® shows that only the pseudo-range data used in the algorithm still gives acceptable results. Based on the simulation results, we can use the on-board GPS receivers' signal only as an alternative to determine the orbit of Sun-Synchronous satellite and therefore circumvents the need for extensive ground support.

  9. SunPy—Python for solar physics

    Science.gov (United States)

    SunPy Community; Mumford, Stuart J.; Christe, Steven; Pérez-Suárez, David; Ireland, Jack; Shih, Albert Y.; Inglis, Andrew R.; Liedtke, Simon; Hewett, Russell J.; Mayer, Florian; Hughitt, Keith; Freij, Nabil; Meszaros, Tomas; Bennett, Samuel M.; Malocha, Michael; Evans, John; Agrawal, Ankit; Leonard, Andrew J.; Robitaille, Thomas P.; Mampaey, Benjamin; Campos-Rozo, Jose Iván; Kirk, Michael S.

    2015-01-01

    This paper presents SunPy (version 0.5), a community-developed Python package for solar physics. Python, a free, cross-platform, general-purpose, high-level programming language, has seen widespread adoption among the scientific community, resulting in the availability of a large number of software packages, from numerical computation (NumPy, SciPy) and machine learning (scikit-learn) to visualization and plotting (matplotlib). SunPy is a data-analysis environment specializing in providing the software necessary to analyse solar and heliospheric data in Python. SunPy is open-source software (BSD licence) and has an open and transparent development workflow that anyone can contribute to. SunPy provides access to solar data through integration with the Virtual Solar Observatory (VSO), the Heliophysics Event Knowledgebase (HEK), and the HELiophysics Integrated Observatory (HELIO) webservices. It currently supports image data from major solar missions (e.g., SDO, SOHO, STEREO, and IRIS), time-series data from missions such as GOES, SDO/EVE, and PROBA2/LYRA, and radio spectra from e-Callisto and STEREO/SWAVES. We describe SunPy's functionality, provide examples of solar data analysis in SunPy, and show how Python-based solar data-analysis can leverage the many existing tools already available in Python. We discuss the future goals of the project and encourage interested users to become involved in the planning and development of SunPy.

  10. Determination of Water Use Effectiveness in Hayrabolu Irrigation Scheme

    Directory of Open Access Journals (Sweden)

    A.N.Yuksel

    2005-05-01

    Full Text Available This study was conducted to determine the effectiveness of irrigation water use in HayraboluIrrigation Scheme, established in 1987 and transferred to irrigation cooperative. The study was completed intwo years in order to minimize the meteorological and environmental effects on evapotranspiration andirrigation water requirement. Irrigation application efficiency and sufficiency of farmer irrigation applicationwere investigated at 20 different farmers’ fields.Pressurized irrigation was prevailed (51 % and irrigation efficiency for sprinkler and surfaceirrigation methods were 61 and 62 %, respectively. Irrigation water losses on the scheme basis was 11,91 %.It was further determined that farmers irrigated their crops according to the phonological observation, did nottake the permissible consumption level of water content and applied insufficient water to satisfy the fieldcapacity. Among the predominantly grown crops, wheat and sunflower were not irrigated assuming that theprecipitation was sufficient to meet their demand while onion and corn were under-supplied. Generally, aneffective irrigation programme was not realised.

  11. Anisotropic microstructure near the sun

    Science.gov (United States)

    Coles, W. A.; Grall, R. R.; Spangler, S. R.; Sakurai, T.; Harmon, J. K.

    1996-07-01

    Radio scattering observations provide a means of measuring a two-dimensional projection of the three-dimensional spatial spectrum of electron density, i.e., in the plane perpendicular to the line of sight. Earlier observations have shown that the microstructure at scales of the order of 10 km becomes highly field-aligned inside of 10 Rsolar [Armstrong et al., 1990]. Earlier work has also shown that density fluctuations at scales larger than 1000 km have a Kolmogorov spectrum, whereas the smaller scale structure has a flatter spectrum and is considerably enhanced above the Kolmogorov ``background'' [Coles et al., 1991]. Here we present new observations made during 1990 and 1992. These confirm the earlier work, which was restricted to one source on a few days, but they suggest that the anisotropy changes abruptly near 6 Rsolar which was not clear in the earlier data. The axial ratio measurements are shown on Figure 1 below. The new observations were made with a more uniform sampling of the spatial plane. They show that contours of constant correlation are elliptical. This is apparently inconsistent with the spatial correlation of the ISEE-3 magnetic field which shows a ``Maltese Cross'' shape [Matthaeus et al., 1990]. However this inconsistency may be only apparent: the magnetic field and density correlations need not have the same shape; the scale of the magnetic field correlations is at least 4 orders of magnitude larger; they are much further from the sun; and they are point measurements whereas ours are path-integrated. We also made two simultaneous measurements, at 10 Rsolar, of the anisotropy on scales of 200 to 4000 km. Significant anisotropy was seen on the smaller scales, but the larger scale structure was essentially isotropic. This suggests that the process responsible for the anisotropic microstructure is independent of the larger scale isotropic turbulence. It is then tempting to speculate that the damping of this anisotropic process inside of 6 Rsolar

  12. The Sun's dusty interstellar environment

    Science.gov (United States)

    Sterken, Veerle

    2016-07-01

    The Sun's dusty interstellar environment Interstellar dust from our immediate interstellar neighborhood travels through the solar system at speeds of ca. 26 km/s: the relative speed of the solar system with respect to the local interstellar cloud. On its way, its trajectories are altered by several forces like the solar radiation pressure force and Lorentz force. The latter is due to the charged dust particles that fly through the interplanetary magnetic field. These trajectories differ per particle type and size and lead to varying fluxes and directions of the flow inside of the solar system that depend on location but also on phase in the solar cycle. Hence, these fluxes and directions depend strongly on the configuration of the inner regions and outer regions of the heliosphere. Several missions have measured this dust in the solar system directly. The Ulysses dust detector data encompasses 16 years of intestellar dust fluxes and approximate directions, Stardust captured returned to Earth a few of these particles sucessfully, and finally the Cassini dust detector allowed for compositional information to be obtained from the impacts on the instrument. In this talk, we give an overview of the current status of interstellar dust research through the measurements made inside of the solar system, and we put them in perspective to the knowledge obtained from more classical astronomical means. In special, we focus on the interaction of the dust with the interplanetary magnetic field, and on what we learn about the dust (and the fields) by comparing the available dust data to computer simulations of dust trajectories. Finally, we synthesize the different methods of observation, their results, and give a preview on new research opportunities in the coming year(s).

  13. Perspectives on the Interior of the Sun

    Indian Academy of Sciences (India)

    S. Μ. Chitre

    2000-09-01

    The interior of the Sun is not directly accessible to observations. Nonetheless, it is possible to infer the physical conditions inside the Sun with the help of structure equations governing its equilibrium and with the powerful observational tools provided by the neutrino fluxes and oscillation frequencies. The helioseismic data show that the internal constitution of the Sun can be adequately represented by a standard solar model. It turns out that a cooler solar core is not a viable solution for the measured deficit of neutrino fluxes, and the resolution of the solar neutrino puzzle should be sought in the realm of particle physics.

  14. The Jovian period in the Sun?

    Science.gov (United States)

    Kotov, V. A.

    2015-09-01

    The 41-year measurements of the Doppler effect of the photosphere performed at the Crimean Astrophysical Observatory, discovered two periods of global oscillations of the Sun: 9600.606(12) s and 9597.929(15) s. Their beat period, 398.4(2.9) d, well agrees with a synodic orbital period of Jupiter, PJ = 398.9 d, raising a new problem for solar physics, cosmogony and cosmology. A hypothesis is advanced that the PJ beating of the Sun is induced by gravitation of Jupiter, revolving in a privileged reference system "the Sun - the Earth".

  15. Semiautomatic sun shots with the WIDIF DIflux

    Science.gov (United States)

    Rasson, Jean L.; Hendrickx, Olivier; Marin, Jean-Luc

    2017-07-01

    The determination of magnetic declination angle entails finding two directions: geographic north and magnetic north. This paper deals with the former. The known way to do it by using the sun's calculable orientation in the sky is improved by using a device based on a WIDIF DIflux theodolite and split photocells positioned on its telescope ocular. Given the WIDIF accurate timing and location provided by the onboard GPS receiver, an astronomical computation can be effected to accurately and quickly determine the sun's azimuth and an auxiliary mark's azimuth. The precise sun's crossing of the split photocell, amplified by the telescope's magnification, allows azimuth accuracies of a few seconds of arc.

  16. Salinity trends in the Ebro River (Spain)

    Science.gov (United States)

    Lorenzo-Gonzalez, M.° Angeles; Isidoro, Daniel; Quilez, Dolores

    2016-04-01

    In the Ebro River Basin (Spain), the increase in water diversion for irrigation (following the increase in irrigated area) and the recovery of natural vegetation in the upper reaches, along with climate change have induced changes in the river flow and its associated salt loads. This study was supported by the Ebro River Basin Administration (CHE) and aimed to establish the trends in the salt concentrations and loads of the Ebro River at Tortosa (no 027, the extreme downstream gauging station). The CHE databases from 1972-73 to 2011-12, including mean monthly flows (Q) and concentration readings (electrical conductivity converted to total dissolved solids -TDS- by regression) from monthly grab samples, have been used. The trends were established by (i) harmonic regression analysis; (ii) linear regression by month; and (iii) the non-parametric Mann-Kendall method. Additionally, (iv) the regressions of TDS on Q in the current and previous months were established, allowing for analyzing separately the trends in TDS linked to- (TDSq) and independent of- (TDSaj) the observed changes in flow. In all cases, the trends were analyzed for different periods within the full span 1973-2012 (1973 to 2012, 1981 to 2012, 1990-2012 and 2001-2012), trying to account for periods with sensibly similar patterns of land use change. An increase in TDS was found for all the periods analyzed that was lower as shorter periods were used, suggesting that lower salinity changes might be taking place in the last years, possibly due to the reduction in the rate of irrigation development and to the on-going irrigation modernization process. The higher seasonal TDS increases were found in autumn and winter months and the increase in TDS was linked both to intrinsic changes in salinity (TDSaj) and to the observed decrease in flow (TDSq). On the other hand, the salt loads decreased, especially in autumn, as a result of the observed flow decrease. These results are based on the observed evolution of

  17. River engineering

    NARCIS (Netherlands)

    De Vries, M.

    1993-01-01

    One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.

  18. The Sustainability of Irrigation Schemes Under Climate Change

    Science.gov (United States)

    Naabil, E.; Lamptey, B. L.; Arnault, J.; Ayorinde, O. A.; Kunstmann, H.

    2015-12-01

    Irrigation is considered to be one of the best practices in agriculture to ensure food security. However water resources that are used for Irrigation activities are increasingly coming under stress, either due to extraction or climate variability and change. To adequately plan and manage water resources so as to ensure their sustainability requires a long term investigations of streamflow and climate. Streamflow analysis and forecasting gives signal of the occurrence of floods and drought situations. However the ability to maximise these early warning signal, especially for small watersheds, require the use of rainfall predictions approaches (Yucel et al., 2015). One approach to extend the predictions of these early warning signals is the coupling of mesoscale numerical weather prediction (NWP) model precipitation estimates with a spatial resolution hydrological model into streamflow estimates (Jasper et al. 2002;Wardah et al. 2008; Yucel et al. 2015). The study explored (1) the potential of the NWP model (WRF) in reproducing observed precipitation over the Tono basin in West Africa, and (2) the potential of a coupled version of WRF with a physics-based hydrological model (WRF-Hydro) in estimating river streamflow. In order to cope with the lack of discharge observation in the Tono basin, the WRF-Hydro performances are evaluated with a water balance approach and dam level observation. The WRF-Hydro predicted dam level is relatively close to the observation (dam level) from January to August (R2=0.93). After this period the deviation from observation increases (R2=0.62). This could be attributed to surface runoff due to peak rainfall (in August) resulting in soil saturation (soil reaching infiltration capacity) into the dam which has not been accounted for in the water balance model. WRF-Hydro has shown to give good estimation of streamflow especially for ungauged stations. Further works requires using WRF-Hydro modeling system for climate projection, and assess the

  19. Irrigation Effects on Hydro-Climatic Change: Basin-Wise Water Balance-Constrained Quantification and Cross-Regional Comparison

    Science.gov (United States)

    Asokan, Shilpa M.; Destouni, Georgia

    2014-05-01

    Hydro-climatic changes driven by human land and water use, including water use for irrigation, may be difficult to distinguish from the effects of global, natural and anthropogenic climate change. This paper quantifies and compares the hydro-climatic change effects of irrigation using a data-driven, basin-wise quantification approach in two different irrigated world regions: the Aral Sea drainage basin in Central Asia and the Indian Mahanadi River Basin draining into the Bay of Bengal. Results show that irrigation-driven changes in evapotranspiration and latent heat fluxes and associated temperature changes at the land surface may be greater in regions with small relative irrigation impacts on water availability in the landscape (here represented by the Mahanadi River Basin) than in regions with severe such impacts (here represented by the Aral region). Different perspectives on the continental part of Earth's hydrological cycle may thus imply different importance assessments of various drivers and impacts of hydro-climatic change. Regardless of perspective, however, actual basin-wise water balance constraints should be accounted to realistically understand and accurately quantify continental water change.

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

    Science.gov (United States)

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

    2016-03-01

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

  1. "A not completely satisfactory attempt": peak discharges and rainfall-runoff relations for Javanese rivers between 1880 and 1940

    NARCIS (Netherlands)

    Ertsen, M.W.

    2011-01-01

    In the early 19th century, the Dutch colonial power started to build irrigation works. A main problem for Dutch irrigation engineers on Java was how to ensure that the structures they built remained intact. The peak discharge regime of a river was an issue closely related to dam safety. Modifying th

  2. Debris and irrigant extrusion potential of 2 rotary systems and irrigation needles.

    Science.gov (United States)

    Altundasar, Emre; Nagas, Emre; Uyanik, Ozgur; Serper, Ahmet

    2011-10-01

    The purpose of this study was to compare the amount of apically extruded irrigant using 2 Ni-Ti rotary systems. Forty mandibular premolars with single canals were randomly assigned into 4 groups. Flower arrangement foam cubes were weighed with a precision balance before being attached to the apical portions of all teeth. In group 1, preparation was completed with ProTaper files. In group 2 canals were prepared with RaCe files. In groups 1 and 2, the irrigant was delivered with a 30-gauge conventional dental needle. In groups 3 and 4, teeth were prepared as in groups 1 and 2 with the exception that the irrigant was delivered with a side-vented irrigation needle. The weight of the extruded material (irrigant and debris) for each group was calculated by comparing the pre- and postinstrumentation weights of the foams used for periapical modeling. Obtained data were analyzed by Kruskal-Wallis and Mann-Whitney U tests, with P equals .05 as the level for statistical significance. ProTaper files used with regular needle irrigation had the highest fluid extrusion. The lowest irrigant extrusion was observed with the RaCe system combined with a side-vented irrigation needle. Within the limitations of this study, it can be concluded that irrigation needle and rotary instruments have an effect on the amount of extruded root canal irrigant.

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

    Science.gov (United States)

    Mozo, Sandra; Llena, Carmen; Forner, Leopoldo

    2012-05-01

    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. The purpose of this review article was to summarize and discuss the available information concerning ultrasonic irrigation in endodontics. 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. 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 layers 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.

  4. Biological degradation of chernozems under irrigation

    Directory of Open Access Journals (Sweden)

    Oksana Naydyonova

    2014-12-01

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

  5. Irrigation Water Management in Latin America

    Directory of Open Access Journals (Sweden)

    Aureo S de Oliveira

    2009-12-01

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

  6. Input Digital Datasets for the Soil-Water Balance Groundwater Recharge Model of the Upper Colorado River Basin

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5...

  7. Finding the lost siblings of the Sun

    Science.gov (United States)

    Liu, Cheng; Feltzing, Sofia; Ruchti, Gregory

    2014-01-01

    We have performed a spectral analysis on 18 stars solar sibling candidate. We found that only one one of the candidateshas solar metallicity and at the same time might have an age comparable to that of the Sun.

  8. Sun and Other Types of Radiation

    Science.gov (United States)

    ... What Causes Cancer? Sun and Other Types of Radiation Learn about the different types of radiation and ... other diseases. Learn more here. Other Types of Radiation Exposure Not all types of radiation have been ...

  9. Sun behaviour after cutaneous malignant melanoma

    DEFF Research Database (Denmark)

    Idorn, L W; Datta, P; Heydenreich, J

    2013-01-01

    Background  It has been reported that patients with cutaneous malignant melanoma (CMM) can lower their risk of a second primary melanoma by limiting recreational sun exposure. Previous studies based on questionnaires and objective surrogate measurements indicate that before their diagnosis......, patients with CMM are exposed to higher ultraviolet radiation (UVR) doses than controls, followed by a reduction after diagnosis. Objectives  In a prospective, observational case-control study, we aimed to assess sun exposure after diagnosis of CMM by objective measurements to substantiate advice about sun...... months and 6 years before the start of the study. During a summer season participants filled in sun exposure diaries daily and wore personal electronic UVR dosimeters in a wristwatch that continuously measured time-stamped UVR doses in standard erythema dose. Results  The UVR dose of recently diagnosed...

  10. UV Photography Shows Hidden Sun Damage

    Science.gov (United States)

    ... mcat1=de12", ]; for (var c = 0; c UV photography shows hidden sun damage A UV photograph gives ... developing skin cancer and prematurely aged skin. Normal photography UV photography 18 months of age: This boy's ...

  11. Nilaja Sun's "No Child...": Reflections on Success

    Science.gov (United States)

    Sun, Nilaja; Alexander, Phillip; Huldeen, Branden; Russell, Ron; Friedman, Melissa

    2007-01-01

    This article describes Nilaja Sun's groundbreaking one-woman show about a TA, her students, and her school, and includes interviews with the author/performer, an excerpt of the work, and a discussion of the organization behind it.

  12. 黄河下游引黄灌区地下水重金属分布及健康风险评估%Distribution and Health Risk Assessment of Heavy Metals of Groundwaters in the Irrigation District of the Lower Reaches of Yellow River

    Institute of Scientific and Technical Information of China (English)

    张妍; 李发东; 欧阳竹; 赵广帅; 李静; 柳强

    2013-01-01

    In order to investigate the contamination levels of groundwater in the irrigation districts of the lower reaches of Yellow River, fifty-nine groundwater samples collected from the irrigation districts of Henan and Shandong provinces, were analyzed. Health risks associated with eleven metals (Ba, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn) were assessed using water pollution index and USEPA health risk assessment model. The average concentrations of Fe with 0.496 mg·L-1 and Zn with 0.445 mg·L-1 were higher than the concentrations of other heavy metals. Concentrations of Fe, Mn, Se and Zn exceeded the relevant standards and the over-standard rates by 27. 12% , 27. 12% , 15. 25% and 5. 09% , respectively. Inverse distance weighted method was applied to estimate the unobserved points and their distribution maps were obtained, which indicated that areas of over-standard heavy metals were Wucheng country, Fan country, Dong'e country, Yucheng city and Guan country. Health risks of ingestion of water for all non-carcinogenic metals are higher than those of dermal absorption, while health risks of ingestion of water for carcinogenic metals is lower than those of dermal absorption. Among the health risks caused by the carcinogenic metals in drinking water and dermal absorption, the highest risks associated with Cr, are seven times and twenty-eight times as that of Cd, respectively, but both were significantly lower than the maximum allowance levels recommended by ICRP (5 × 10 -5 a-1 ). The non-carcinogenic metal risks( Ba, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn) , ranging from 1. 73 × 10 -13 to 3. 46 ×10 -10 a-1 in dermal absorption and from 1. 13× 10-1 to 6. 06 ×10-8 a-1 in drinking water, were much lower than the maximum allowance levels.%为了解黄河下游引黄灌区地下水重金属污染水平,在引黄灌区豫、鲁两省采集59个地下水样品,定量分析了11种重金属元素(Ba、Cd、Cr、Cu、Fe、Mn、Mo、Ni、Pb、Se和Zn)的含

  13. Using a Smart-phone for Collecting Discharge Data in Irrigation Furrows in Tanzania.

    Science.gov (United States)

    Pena-Haro, S.; Lüthi, B.; Philippe, T.; Naudascher, R.; Siegfried, T.

    2015-12-01

    When managed effectively and sustainably crop yield in irrigated agriculture can be up to three times than in rainfed agriculture. Unsurprisingly, irrigation agriculture is globally gaining in importance. This is especially true in Africa where the share of irrigated to rainfed agriculture in terms of area cultivated is below global averages. A large-scale expansion of irrigation, nonetheless has the potential to alter the natural hydrological cycle at local up to basin scales. In all cases, a good understanding of the water balance is needed. However, and especially in the developing context, data are scarce and knowledge about the available resources is most often not present. Some of the key reasons are: a) traditional monitoring approaches do not scale in terms of costs, b) repair is difficult and c) vandalism. There is a clear need of cheaper and easy-to-use methods for gathering information on water use and water availability.We have developed a mobile device application for measuring discharge in rivers and irrigation furrows. The discharge is computed by analysing a few seconds of a movie recorded using the built-in camera. The great advantage is that the only requirement is that the field of view contains two reference markers with known scale and with known position relative to the channel geometry, a priori knowledge on the channel geometry and its roughness. The other great advantage is that the data collected (water level, surface velocity and discharge) can be sent via SMS or web-service to a central database.The app is being currently used in a formerly ungauged catchment, the Themi River, which is part of the Pangani Basin in Tanzania. Furrow leaders and community members measure furrow discharges on-farm and monitor water levels in rivers off-farm. These community members were given a smartphone and received thorough training. Additionally, off-grid members have received a mobile recharging solution. Operational Expenses of the community members

  14. The Sun murrab Baltimaadesse ja Soome

    Index Scriptorium Estoniae

    2008-01-01

    Aprillis andis ansambel Tanel Padar & The Sun Soomes, Lätis, Leedus ja Eestis üksteist kontserti. Heliplaadi "Here Gomes The Sun" lugu "Hopelessness You" on Soome raadiote tipp 300s neljakümnendal kohal, lugu "Learn the game" on Leedu FM99 raadios 33 enim mängitava loo seas, laul "One of those days" saavutas Läti raadio SWH rokkmuusika edetabelis teise koha.

  15. Optimal control of sun tracking solar concentrators

    Science.gov (United States)

    Hughes, R. O.

    1979-01-01

    Application of the modern control theory to derive an optimal sun tracking control for a point focusing solar concentrator is presented. A standard tracking problem converted to regulator problem using a sun rate input achieves an almost zero steady state tracking error with the optimal control formulation. However, these control techniques are costly because optimal type algorithms require large computing systems, thus they will be used mainly as comparison standards for other types of control algorithms and help in their development.

  16. The Sun murrab Baltimaadesse ja Soome

    Index Scriptorium Estoniae

    2008-01-01

    Aprillis andis ansambel Tanel Padar & The Sun Soomes, Lätis, Leedus ja Eestis üksteist kontserti. Heliplaadi "Here Gomes The Sun" lugu "Hopelessness You" on Soome raadiote tipp 300s neljakümnendal kohal, lugu "Learn the game" on Leedu FM99 raadios 33 enim mängitava loo seas, laul "One of those days" saavutas Läti raadio SWH rokkmuusika edetabelis teise koha.

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

    Science.gov (United States)

    Ermolaeva, Olga; Zeyliger, Anatoly

    2017-04-01

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

  18. Impact of Soil Resistance to Penetration in the Irrigation Interval of Supplementary Irrigation Systems at the Humid Pampa, Argentina

    Science.gov (United States)

    Hernández J., P.; Befani M., R.; Boschetti N., G.; Quintero C., E.; Díaz E., L.; Lado, M.; Paz-González, A.

    2015-04-01

    The Avellaneda District, located in northeastern of Santa Fe Province, Argentina, has an average annual rainfall of 1250 mm per year, but with a high variability in their seasonal distribution. Generally, the occurrence of precipitation in winter is low, while summer droughts are frequent. The yearly hydrological cycle shows a water deficit, given that the annual potential evapotranspiration is estimated at 1330 mm. Field crops such as soybean, corn, sunflower and cotton, which are affected by water stress during their critical growth periods, are dominant in this area. Therefore, a supplemental irrigation project has been developed in order to identify workable solutions. This project pumps water from Paraná River to provide a water supply to the target area under irrigation. A pressurized irrigation system operating on demand provides water to a network of channels, which in turn deliver water to farms. The scheduled surface of irrigation is 8800 hectares. The maximum flow rate was designed to be 8.25 m3/second. The soils have been classified as Aquic Argiudolls in areas of very gentle slopes, and Vertic Argiudolls in flat and concave reliefs; neither salinity nor excess sodium affect the soils of the study are. The objective of this study was to provide a quantitative data set to manage the irrigation project, through the determination of available water (AW), easily available water (EAw) and optimal water range (or interval) of the soil horizons. The study has been conducted in a text area of 1500 hectares in surface. Five soil profiles were sampled to determine physical properties (structure stability, effective root depth, infiltration, bulk density, penetration resistance and water holding capacity), chemical properties (pH, cation exchange capacity, base saturation, salinity, and sodium content ) and morphological characteristics of the successive horizons. Also several environmental characteristics were evaluated, including: climate, topographic

  19. Irrigation of treated wastewater in Braunschweig, Germany

    DEFF Research Database (Denmark)

    Ternes, T.A.; Bonerz, M.; Herrmann, N.

    2007-01-01

    In this study the fate of pharmaceuticals and personal care products which are irrigated on arable land with treated municipal waste-water was investigated. In Braunschweig, Germany, wastewater has been irrigated continuously for more than 45 years. In the winter time only the effluent...... of digested sludge, because many polar compounds do not sorb to sludge and lipophilic compounds are not mobile in the soil-aquifer. Most of the selected PPCPs were never detected in any of the lysimeter or groundwater samples, although they were present in the treated wastewater irrigated onto the fields...

  20. Irrigation water use in Kansas, 2013

    Science.gov (United States)

    Lanning-Rush, Jennifer L.

    2016-03-22

    This report, prepared by the U.S. Geological Survey in cooperation with the Kansas Department of Agriculture, Division of Water Resources, presents derivative statistics of 2013 irrigation water use in Kansas. The published regional and county-level statistics from the previous 4 years (2009–12) are shown with the 2013 statistics and are used to calculate a 5-year average. An overall Kansas average and regional averages also are calculated and presented. Total reported irrigation water use in 2013 was 3.3 million acre-feet of water applied to 3.0 million irrigated acres.

  1. How to Observe the Sun Safely

    CERN Document Server

    Macdonald, Lee

    2012-01-01

    How to Observe the Sun Safely, Second Edition gives all the basic information and advice the amateur astronomer needs to get started in observing our own ever-fascinating star. Unlike many other astronomical objects, you do not need a large telescope or expensive equipment to observe the Sun. And it is possible to take excellent pictures of the Sun with today's low-cost digital cameras! This book surveys what is visible on the Sun and then describes how to record solar features and measure solar activity levels. There is also an account of how to use H-alpha and Calcium-K filters to observe and record prominences and other features of the solar chromosphere, the Sun's inner atmosphere. Because we are just entering a period of high activity on the Sun, following a long, quiet period, this is a great time to get involved with solar observing. Still emphasizing safety first, this Second Edition reflects recent and exciting advances in solar observing equipment. Chapters 6 through 8 have been completely revised ...

  2. Orientation in birds. The sun compass.

    Science.gov (United States)

    Schmidt-Koenig, K; Ganzhorn, J U; Ranvaud, R

    1991-01-01

    The sun compass was discovered by G. Kramer in caged birds showing migratory restlessness. Subsequent experiments with caged birds employing directional training and clock shifts, carried out by Hoffman and Schmidt-Koenig, showed that the sun azimuth is used, and the sun altitude ignored. In the laboratory, McDonald found the accuracy to be +/- 3 degrees(-)+/- 5 degrees. According to Hoffmann and Schmidt-Koenig, caged birds trained at medium northern latitudes were able to allow for the sun's apparent movement north of the arctic circle, but not in equatorial and trans-equatorial latitudes. In homing experiments, and employing clock shifts, Schmidt-Koenig demonstrated that the sun compass is used by homing pigeons during initial orientation. This finding is the principal evidence for the existence of a map-and-compass navigational system. Pigeons living in equatorial latitudes utilize the sun compass even under the extreme solar conditions of equinox, achieving angular resolution of about 3 degrees in homing experiments. According to preliminary analyses, the homing pigeons' ephemerides are retarded by several weeks (Ranvaud, Schmidt-Koenig, Ganzhorn et al.).

  3. SunPy: Solar Physics in Python

    Science.gov (United States)

    Ryan, Daniel; Christe, Steven; Mumford, Stuart; Perez Suarez, David; Ireland, Jack; Shih, Albert Y.; Inglis, Andrew; Liedtke, Simon; Hewett, Russel

    2015-04-01

    SunPy is a community-developed open-source software library for solar physics. It is written in Python, a free, cross-platform, general-purpose, high-level programming language which is being increasingly adopted throughout the scientific community as well as further afield. This has resulted in a wide array of software packages useful for scientific computing, from numerical computation (NumPy, SciPy, etc.), to machine learning (scifitlearn), to visualization and plotting (matplotlib). SunPy aims to provide required specialised software for analysing solar and heliospheric datasets in Python. The current version is 0.5 with 0.6 expected to be released later this year. SunPy provides solar data access through integration with the Virtual Solar Observatory (VSO), the Heliophysics Event Knowledgebase (HEK), and the HELiophysics Integrated Observatory (HELIO) webservices. It supports common data types from major solar missions such as images (SDO/AIA, STEREO, PROBA2/SWAP etc.), time series (GOES/XRS, SDO/EVE, PROBA2/LYRA), and radio spectra (e-Callisto, STEREO/WAVES). SunPy’s code base is publicly available through github.com and can be contributed to by anyone. In this poster we demonstrate SunPy’s functionality and future goals of the project. We also encourage interested users to become involved in further developing SunPy.

  4. Reform in Indian canal irrigation: does technology matter?

    NARCIS (Netherlands)

    Narain, V.

    2008-01-01

    This paper examines the implications of technology - the design of canal irrigation for irrigation management reform. With reference to two different design systems in Indian irrigation - shejpali and warabandi - it shows that the potential for reform varies with the design of canal irrigation. Thre

  5. Reform in Indian canal irrigation: does technology matter?

    NARCIS (Netherlands)

    Narain, V.

    2008-01-01

    This paper examines the implications of technology - the design of canal irrigation for irrigation management reform. With reference to two different design systems in Indian irrigation - shejpali and warabandi - it shows that the potential for reform varies with the design of canal irrigation.

  6. Long-term trends in field level irrigation water demand in Mahanadi delta districts - a hydrological modeling approach for coping with climate change

    Science.gov (United States)

    Raju Pokkuluri, Venkat; Rao, Diwakar Parsi Guru; Hazra, Sugata; Srikant Kulkarni, Sunil

    2017-04-01

    India uses its 85 percent of available water resources for irrigation making it the country with largest net irrigated area in the world. With one of the largest delta plains, sustaining the needs of irrigation supplies is critical for food security and coping with challenges of climate change. The extensive development of upstream river basins/catchments is posing serious challenge and constrains to the water availability to delta regions, which depend on the controlled/regulated flows from the upstream catchments. The irrigation water demands vary due to changes in agricultural practices, cropping pattern and changing climate conditions. Estimation of realistic irrigation water demand and its trend over time is critical for meeting the supplementary water needs of productive agricultural lands in delta plains and there by coping the challenges of extensive upstream river basin development and climate change. The present study carried out in delta districts of Mahanadi river in Odisha State of India, wherein the long-term trends in field level irrigation water requirements were estimated, both on spatial & temporal scales, using hydrological modeling framework. This study attempts to estimate field level irrigation water requirements through simulation of soil water balance during the crop growing season through process based hydrological modeling framework. The soil water balance computations were carried out using FAO-56 framework, by modifying the crop coefficient (Kc) proportional to the water stress coefficient (Ks), which is a function of root zone depletion of water. Daily meteorological data, spatial cropping pattern, terrain are incorporated in the soil water balance simulation in the model. The irrigation water demand is derived considering the exclusion of soil water stress for each model time step. The field level irrigation water requirement at 8 day interval had been estimated for the each Rabi season (post-monsoon) spanning over 1986 to 2015. The

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

    Science.gov (United States)

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

    2013-01-01

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

  8. Microbiological water quality in a large irrigation system: El Valle del Yaqui, Sonora México.

    Science.gov (United States)

    Gortáres-Moroyoqui, Pablo; Castro-Espinoza, L; Naranjo, Jaime E; Karpiscak, Martin M; Freitas, Robert J; Gerba, Charles P

    2011-01-01

    The primary objective of this study was to determine the microbial water quality of a large irrigation system and how this quality varies with respect to canal size, impact of near-by communities, and the travel distance from the source in the El Valle del Yaqui, Sonora, México. In this arid region, 220,000 hectares are irrigated with 80% of the irrigation water being supplied from an extensive irrigation system including three dams on the Yaqui River watershed. The stored water flows to the irrigated fields through two main canal systems (severing the upper and lower Yaqui Valley) and then through smaller lateral canals that deliver the water to the fields. A total of 146 irrigation water samples were collected from 52 sample sites during three sampling events. Not all sites could be accessed on each occasion. All of the samples contained coliform bacteria ranging from 1,140 to 68,670 MPN/100 mL with an arithmetic mean of 11,416. Ninety-eight percent of the samples contained less than 1,000 MPN/100 mL Escherichia coli, with an arithmetic mean of 291 MPN/100 mL. Coliphage were detected in less than 30% of the samples with an arithmetic average equal to 141 PFU/100 mL. Enteroviruses, Cryptosporidium oocysts, and Giardia cysts were also detected in the canal systems. No significant difference was found in the water quality due to canal system (upper or lower Yaqui Valley), canal-size (main vs. lateral), distance from source, and the vicinity of human habitation (presence of various villages and towns along the length of the canals). There was a significant decrease in coliforms (p < 0.011) and E. coli (< 0.022) concentrations as travel distance increased from the City of Obregón.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-02-01

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

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

    OpenAIRE

    Paudel, K.

    2010-01-01

    Sediment transport in irrigation canals The sediment transport aspect is a major factor in irrigation development as it determines to a large extent the sustainability of an irrigation scheme, particularly in case of unlined canals in alluvial soils. Investigations in this respect started since Kennedy published his channel-forming discharge theory in 1895. Subsequently different theories have been developed and are used around the world. All of them assume uniform and steady flow conditions ...

  11. Transpirative Deficit Index (TDI) for the management of water scarcity in irrigated areas: development and application in northern Italy

    Science.gov (United States)

    Borghi, Anna; Facchi, Arianna; Rienzner, Michele; Gandolfi, Claudio

    2016-04-01

    In Europe, the monitoring and assessment of drought is entrusted to the European Drought Observatory (EDO). EDO indicators are calculated considering rainfed agriculture and delivered on a 5 km grid. However, in southern Europe, irrigation may compensate for potentially severe agricultural droughts and specific water scarcity indicators that explicitly consider irrigation are needed. In the Po River Plain, irrigated crops cover more than 70% of the agricultural land, massive amounts of water are diverted from rivers for irrigation, and surface irrigation methods are largely applied. Nowadays, the region is not a water scarce basin, but irrigation water shortages have occurred with increased frequency during the last two decades. Moreover, a recent EU report shows that the Po River Plain is included among areas in Europe that by 2030 shall be affected by water scarcity. In this context, a study was started to select and develop indicators for the management and prevention of Water Scarcity and Drought (WS&D) based on the synergic use of hydrological modelling and Earth Observation data applied at a spatial scale of interest for end-users (250m grid). These indicators shall be better suited for the assessment of WS&D in Italy as well as in other southern European countries. This work presents the development and the application of the TDI (Transpirative Deficit Index) to a study area, within the Po River Plain. TDI is an agricultural drought index based on the transpiration deficit (TDx, calculated as the difference between potential and actual transpiration), computed by the spatially distributed hydrological model IDRAGRA and cumulated over a period of x days. TDx for each day of a specific year is compared to the long-term TDx probability distribution (e.g., over 20-30 years), which is transformed into a standardized normal distribution. The non-exceedance probability of TDx is finally expressed in terms of unit of standard deviation (TDI), following the approach

  12. Effects of irrigation efficiency on chemical transport processes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Irrigation practices greatly affect sustainable agriculture development. In this study, we investigated the effects of irrigation efficiency on water flow and chemical transport in soils, which had significant impact on the environment. Field dye staining experiments were conducted at different soils with various irrigation amount. Image analysis was conducted to study the heterogeneous flow patterns and their relationships with the irrigation efficiency. Irrigation efficiency and its environmental effects were evaluated using various indictors, including application efficiency, deep percolation ratio, storage efficiency, and uniformity. Under the same irrigation condition, soil chemical distributions were more heterogeneous than soil water distributions. The distributions were mainly affected by soil texture, initial soil water content, and irrigation amount. Storage efficiency, irrigation uniformity, and deep percolation ratio increased with irrigation amount. Since the chemical distribution uniformity was lower than the water uniformity, the amount of chemical leaching increased sharply with decrease of irrigation uniformity, which resulted in high environmental risks of groundwater pollution.

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

    Directory of Open Access Journals (Sweden)

    AR Sanda

    2014-09-01

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

  14. Farmers’ Willingness to Pay for Irrigation Water: A Case of Tank Irrigation Systems in South India

    Directory of Open Access Journals (Sweden)

    Karthikeyan Chandrasekaran

    2009-08-01

    Full Text Available The economic value of tank irrigation water was determined through Contingency Valuation Method by analyzing farmers’ willingness to pay for irrigation water under improved water supply conditions during wet and dry seasons of paddy cultivation. Quadratic production function was also used to determine the value of irrigation water. The comparison of the economic value of water estimated using different methods strongly suggests that the present water use pattern will not lead to sustainable use of the resource in the tank command areas. Policy options for sustainable use of irrigation water and management of tanks in India were suggested.

  15. The future of the reservoirs in the Siret River Basin considering the sediment transport of rivers (ROMANIA)

    OpenAIRE

    Petru OLARIU; Gianina Maria COJOC; Alina TIRNOVAN; Obreja, Florin

    2015-01-01

    The Siret River Basin is characterized by an important use of hydro potential, resulted in the number of reservoirs constructed and operational. The cascade power stage of the reservoirs on Bistrita and Siret rivers indicate the anthropic interventions with different purposes (hydro energy, water supply, irrigation etc.) in the Siret River Basin. In terms of the capacity in the Siret River Basin there is a dominance of the small capacity reservoirs, which is given by the less than 20 mil m³ v...

  16. Strategic irrigation against apple scab (Venturia inaequalis)

    DEFF Research Database (Denmark)

    Korsgaard, Maren

    2012-01-01

    In Denmark there are several organic orchards, that do not spray at all, and they seek non-spraying methods to prevent apple scab. In this pilot trial, irrigation with water at strategic moments was tested to prevent scab-infection. In April-June 2011 in five organic orchards we irrigated...... the orchard floor, to force the ascospores to be released. We irrigated with at least 0.2 mm of water in dry periods, at least 12 hours before rain forecast. The idea was to empty the stock of ascospores during dry spells, so they would dry out without infecting the leaves. To find the best strategic times...... for irrigation, we used the local weather forecast and the scab-warning programme Rimpro based on data from climate stations located in the orchards. In this first year of trial we experienced difficulties in spreading the water evenly. A water wagon turned out to work better than sprinklers. We found...

  17. Estimated Irrigated Agricultural Water Use In 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a 100-meter cell resolution raster dataset of estimated use of irrigated agricultural water use data for the southwestern U.S. The dataset was...

  18. Proceedings of the solar irrigation workshop

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-06-01

    The ERDA Solar Irrigation Workshop was structured to be a major vehicle for information dissemination and technology transfer. It covered a wide range of subject matter related to crop irrigation including current hardware, economics, experiments, and international requirements. Speakers represented manufacturers, ranchers, governmental entities, universities and research firms. The proceedings consist of one page abstracts for each presentation, a brief biographical sketch of each speaker and sources for further information on each subject.

  19. Smart Water Conservation System for Irrigated Landscape

    Science.gov (United States)

    2016-05-01

    by the Energy Independence and Security Act (EISA). Reducing potable water demand for landscape irrigation correlates to lower energy costs necessary...irrigation is necessary. Typically, timer-based systems are adjusted higher than needed to account for consecutive hot days that stress turf beyond the...implementation at sports field, parade grounds, and/or landscape near buildings. Appendix C details the life cycle cost for the smart water

  20. Irrigation enhances precipitation at the mountains downwind

    Directory of Open Access Journals (Sweden)

    J. Jódar

    2010-05-01

    Full Text Available Atmospheric circulation models predict an irrigation-rainfall feedback. However, actual field evidences are very weak. We present strong field evidence about an increase in rainfall at the mountains located downwind of irrigated zones. We chose two regions, located in semiarid southern Spain, where irrigation started at a well defined date, and we analyzed rainfall statistics before and after the beginning of irrigation. Analyzed statistics include the variation of (1 mean rainfall Δ P, (2 ratio of monthly precipitation to annual precipitation Δ r, and (3 number of months with minimum rainfall episodes Δ Pmin after a transition period from unirrigated to irrigated conditions. All of them show statistically significant increases. Δ P and Δ r show larger and more statistically significant variations in June and July. Their variation is proportional to the mean annual water volume applied in the neighboring upwind irrigation lands. Variations in Δ Pmin are statistically significant in the whole summer. That is, the number of months with some rain displays a relevant increase after irrigation. However, increase in rainfall while statistically significant is distributed over a broad region, so that it is of little relevance from a water resources perspective. The joint increment in Δ P and Δ Pmin after the irrigation transition period denotes a net increase in the number of months having a minimum cumulated precipitation in summer.