WorldWideScience

Sample records for lowered water table

  1. Water table lowering to improve excavation performance and to reduce acid mine drainage

    International Nuclear Information System (INIS)

    Koppe, J.C.; Costa, J.F.; Laurent, O. Jr.

    1995-01-01

    This paper analyses the water table level fluctuations using wells located adjacent to the stripping cuts at the Butia-Leste coal mine, southernmost of Brazil. Piezometers monitored the water table fluctuations. Geological mapping provided additional information aiding the interpretation of the results. A contouring software was also used as tool to aid the interpretation of the data and the results visualisation. The parameters necessary in selecting the location of the wells and pumping volumes were calculated from the data obtained in the water table lowering tests. The results were used to minimise two main problems: the generation of acid mine drainage and the reduction of the excavation performance of the fleet used in overburden removal. 7 refs., 5 figs., 3 tabs

  2. Manipulative lowering of the water table during summer does not affect CO2 emissions and uptake in a fen in Germany.

    Science.gov (United States)

    Muhr, Jan; Höhle, Juliane; Otieno, Dennis O; Borken, Werner

    2011-03-01

    We simulated the effect of prolonged dry summer periods by lowering the water table on three manipulation plots (D(1-3)) in a minerotrophic fen in southeastern Germany in three years (2006-2008). The water table at this site was lowered by drainage and by excluding precipitation; three nonmanipulated control plots (C(1-3)) served as a reference. We found no significant differences in soil respiration (R(Soil)), gross primary production (GPP), or aboveground respiration (R(AG)) between the C(1-3) and D(1-3) plots in any of the measurement years. The water table on the control plots was naturally low, with a median water table (2006-2008) of 8 cm below the surface, and even lower during summer when respiratory activity was highest, with median values (C(1-3)) between 11 and 19 cm below the surface. If it is assumed that oxygen availability in the uppermost 10 cm was not limited by the location of the water table, manipulative lowering of the water table most likely increased oxygen availability only in deeper peat layers where we expect R(Soil) to be limited by poor substrate quality rather than anoxia. This could explain the lack of a manipulation effect. In a second approach, we estimated the influence of the water table on R(Soil) irrespective of treatment. The results showed a significant correlation between R(Soil) and water table, but with R(Soil) decreasing at lower water tables rather than increasing. We thus conclude that decomposition in the litter layer is not limited by waterlogging in summer, and deeper peat layers bear no significant decomposition potential due to poor substrate quality. Consequently, we do not expect enhanced C losses from this site due to increasing frequency of dry summers. Assimilation and respiration of aboveground vegetation were not affected by water table fluctuations between 10 and >60 cm depth, indicating the lack of stress resulting from either anoxia (high water table) or drought (low water table).

  3. Molecular mechanisms of water table lowering and nitrogen deposition in affecting greenhouse gas emissions from a Tibetan alpine wetland.

    Science.gov (United States)

    Wang, Hao; Yu, Lingfei; Zhang, Zhenhua; Liu, Wei; Chen, Litong; Cao, Guangmin; Yue, Haowei; Zhou, Jizhong; Yang, Yunfeng; Tang, Yanhong; He, Jin-Sheng

    2017-02-01

    Rapid climate change and intensified human activities have resulted in water table lowering (WTL) and enhanced nitrogen (N) deposition in Tibetan alpine wetlands. These changes may alter the magnitude and direction of greenhouse gas (GHG) emissions, affecting the climate impact of these fragile ecosystems. We conducted a mesocosm experiment combined with a metagenomics approach (GeoChip 5.0) to elucidate the effects of WTL (-20 cm relative to control) and N deposition (30 kg N ha -1  yr -1 ) on carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) fluxes as well as the underlying mechanisms. Our results showed that WTL reduced CH 4 emissions by 57.4% averaged over three growing seasons compared with no-WTL plots, but had no significant effect on net CO 2 uptake or N 2 O flux. N deposition increased net CO 2 uptake by 25.2% in comparison with no-N deposition plots and turned the mesocosms from N 2 O sinks to N 2 O sources, but had little influence on CH 4 emissions. The interactions between WTL and N deposition were not detected in all GHG emissions. As a result, WTL and N deposition both reduced the global warming potential (GWP) of growing season GHG budgets on a 100-year time horizon, but via different mechanisms. WTL reduced GWP from 337.3 to -480.1 g CO 2 -eq m -2 mostly because of decreased CH 4 emissions, while N deposition reduced GWP from 21.0 to -163.8 g CO 2 -eq m -2 , mainly owing to increased net CO 2 uptake. GeoChip analysis revealed that decreased CH 4 production potential, rather than increased CH 4 oxidation potential, may lead to the reduction in net CH 4 emissions, and decreased nitrification potential and increased denitrification potential affected N 2 O fluxes under WTL conditions. Our study highlights the importance of microbial mechanisms in regulating ecosystem-scale GHG responses to environmental changes. © 2016 John Wiley & Sons Ltd.

  4. Hydrogeologic characteristics and geospatial analysis of water-table changes in the alluvium of the lower Arkansas River Valley, southeastern Colorado, 2002, 2008, and 2015

    Science.gov (United States)

    Holmberg, Michael J.

    2017-05-15

    The U.S. Geological Survey in cooperation with the Lower Arkansas Valley Water Conservancy District measures groundwater levels periodically in about 100 wells completed in the alluvial material of the Arkansas River Valley in Pueblo, Crowley, Otero, Bent, and Prowers Counties in southeastern Colorado, of which 95 are used for the analysis in this report. The purpose of this report is to provide information to water-resource administrators, managers, planners, and users about groundwater characteristics in the alluvium of the lower Arkansas Valley extending roughly 150 miles between Pueblo Reservoir and the Colorado-Kansas State line. This report includes three map sheets showing (1) bedrock altitude at the base of the alluvium of the lower Arkansas Valley; (2) estimated spring-to-spring and fall-to-fall changes in water-table altitude between 2002, 2008, and 2015; and (3) estimated saturated thickness in the alluvium during spring and fall of 2002, 2008, and 2015, and thickness of the alluvium in the lower Arkansas Valley. Water-level changes were analyzed by geospatial interpolation methods.Available data included all water-level measurements made between January 1, 2001, and December 31, 2015; however, only data from fall and spring of 2002, 2008, and 2015 are mapped in this report. To account for the effect of John Martin Reservoir in Bent County, Colorado, lake levels at the reservoir were assigned to points along the approximate shoreline and were included in the water-level dataset. After combining the water-level measurements and lake levels, inverse distance weighting was used to interpolate between points and calculate the altitude of the water table for fall and spring of each year for comparisons. Saturated thickness was calculated by subtracting the bedrock surface from the water-table surface. Thickness of the alluvium was calculated by subtracting the bedrock surface from land surface using a digital elevation model.In order to analyze the response

  5. Carbon dioxide flux and net primary production of a boreal treed bog: Responses to warming and water-table-lowering simulations of climate change

    Science.gov (United States)

    Munir, T. M.; Perkins, M.; Kaing, E.; Strack, M.

    2015-02-01

    Midlatitude treed bogs represent significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites: control, recent (1-3 years; experimental) and older drained (10-13 years), with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and estimated tree root respiration (Rr; across hummock-hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011-2013. The CO2-C balance was calculated by adding the net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to the driest and the warmest 2013, the control site was a CO2-C sink of 92, 70 and 76 g m-2, the experimental site was a CO2-C source of 14, 57 and 135 g m-2, and the drained site was a progressively smaller source of 26, 23 and 13 g CO2-C m-2. The short-term drainage at the experimental site resulted in small changes in vegetation coverage and large net CO2 emissions at the microforms. In contrast, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) on the hummocks and lichen in the hollows leading to the highest CO2 uptake at the drained hummocks and significant losses in the hollows. The tree NPP (including above- and below-ground growth and litter fall) in 2011 and 2012 was significantly higher at the drained site (92 and 83 g C m-2) than at the experimental (58 and 55 g C m-2) and control (52 and 46 g C m-2) sites. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ~ 1 °C and differential air warming of ~ 6 °C at midday full sun over the study years. Warming significantly enhanced shrub growth and the CO2 sink function of the drained

  6. Response of anaerobic carbon cycling to water table manipulation in an Alaskan rich fen

    Science.gov (United States)

    E.S. Kane; M.R. Chivers; M.S. Turetsky; C.C. Treat; D.G. Petersen; M. Waldrop; J.W. Harden; A.D. McGuire

    2013-01-01

    To test the effects of altered hydrology on organic soil decomposition, we investigated CO2 and CH4 production potential of rich-fen peat (mean surface pH = 6.3) collected from a field water table manipulation experiment including control, raised and lowered water table treatments. Mean anaerobic CO2...

  7. Woody riparian vegetation response to different alluvial water table regimes

    Science.gov (United States)

    Shafroth, P.B.; Stromberg, J.C.; Patten, D.T.

    2000-01-01

    Woody riparian vegetation in western North American riparian ecosystems is commonly dependent on alluvial groundwater. Various natural and anthropogenic mechanisms can cause groundwater declines that stress riparian vegetation, but little quantitative information exists on the nature of plant response to different magnitudes, rates, and durations of groundwater decline. We observed groundwater dynamics and the response of Populus fremontii, Salix gooddingii, and Tamarix ramosissima saplings at 3 sites between 1995 and 1997 along the Bill Williams River, Arizona. At a site where the lowest observed groundwater level in 1996 (-1.97 m) was 1.11 m lower than that in 1995 (-0.86 m), 92-100% of Populus and Salix saplings died, whereas 0-13% of Tamarix stems died. A site with greater absolute water table depths in 1996 (-2.55 m), but less change from the 1995 condition (0.55 m), showed less Populus and Salix mortality and increased basal area. Excavations of sapling roots suggest that root distribution is related to groundwater history. Therefore, a decline in water table relative to the condition under which roots developed may strand plant roots where they cannot obtain sufficient moisture. Plant response is likely mediated by other factors such as soil texture and stratigraphy, availability of precipitation-derived soil moisture, physiological and morphological adaptations to water stress, and tree age. An understanding of the relationships between water table declines and plant response may enable land and water managers to avoid activities that are likely to stress desirable riparian vegetation.

  8. Cokriging model for estimation of water table elevation

    International Nuclear Information System (INIS)

    Hoeksema, R.J.; Clapp, R.B.; Thomas, A.L.; Hunley, A.E.; Farrow, N.D.; Dearstone, K.C.

    1989-01-01

    In geological settings where the water table is a subdued replica of the ground surface, cokriging can be used to estimate the water table elevation at unsampled locations on the basis of values of water table elevation and ground surface elevation measured at wells and at points along flowing streams. The ground surface elevation at the estimation point must also be determined. In the proposed method, separate models are generated for the spatial variability of the water table and ground surface elevation and for the dependence between these variables. After the models have been validated, cokriging or minimum variance unbiased estimation is used to obtain the estimated water table elevations and their estimation variances. For the Pits and Trenches area (formerly a liquid radioactive waste disposal facility) near Oak Ridge National Laboratory, water table estimation along a linear section, both with and without the inclusion of ground surface elevation as a statistical predictor, illustrate the advantages of the cokriging model

  9. Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed

    Science.gov (United States)

    Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S.

    2013-01-01

    Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been proposed, but in general remain entirely hypothetical. For mineralized watersheds, a favored hypothesis is that falling water tables caused by declining recharge rates allow an increasing volume of sulfide-bearing rock to become exposed to air, thus oxygen. Here, we test the hypothesis that falling water tables are the primary cause of an increase in metals and SO4 (100-400%) observed since 1980 in the Upper Snake River (USR), Colorado. The USR drains an alpine watershed geologically and climatologically representative of many others in mineralized areas of the western U.S. Hydrologic and chemical data collected from 2005 to 2011 in a deep monitoring well (WP1) at the top of the USR watershed are utilized. During this period, both water table depths and groundwater SO4 concentrations have generally increased in the well. A numerical model was constructed using TOUGHREACT that simulates pyrite oxidation near WP1, including groundwater flow and oxygen transport in both saturated and unsaturated zones. The modeling suggests that a falling water table could produce an increase in metals and SO4 of a magnitude similar to that observed in the USR (up to 300%). Future water table declines may produce limited increases in sulfide weathering high in the watershed because of the water table dropping below the depth of oxygen penetration, but may continue to enhance sulfide weathering lower in the watershed where water tables are shallower. Advective air (oxygen) transport in the unsaturated zone caused by seasonally variable recharge and associated water table fluctuations was found to have little influence on pyrite

  10. Decreased summer water table depth affects peatland vegetation

    NARCIS (Netherlands)

    Breeuwer, A.J.G.; Robroek, B.J.M.; Limpens, J.; Heijmans, M.M.P.D.; Schouten, M.G.C.; Berendse, F.

    2009-01-01

    Climate change can be expected to increase the frequency of summer droughts and associated low water tables in ombrotrophic peatlands. We studied the effects of periodic water table drawdown in a mesocosm experiment. Mesocosms were collected in Southern Sweden, and subsequently brought to an

  11. Developing Automatic Water Table Control System for Reducing Greenhouse Gas Emissions from Paddy Fields

    Science.gov (United States)

    Arif, C.; Fauzan, M. I.; Satyanto, K. S.; Budi, I. S.; Masaru, M.

    2018-05-01

    Water table in rice fields play important role to mitigate greenhouse gas (GHG) emissions from paddy fields. Continuous flooding by maintenance water table 2-5 cm above soil surface is not effective and release more GHG emissions. System of Rice Intensification (SRI) as alternative rice farming apply intermittent irrigation by maintaining lower water table is proven can reduce GHG emissions reducing productivity significantly. The objectives of this study were to develop automatic water table control system for SRI application and then evaluate the performances. The control system was developed based on fuzzy logic algorithms using the mini PC of Raspberry Pi. Based on laboratory and field tests, the developed system was working well as indicated by lower MAPE (mean absolute percentage error) values. MAPE values for simulation and field tests were 16.88% and 15.80%, respectively. This system can save irrigation water up to 42.54% without reducing productivity significantly when compared to manual irrigation systems.

  12. Free product recovery at spill sites with fluctuating water tables

    International Nuclear Information System (INIS)

    Parker, J.C.; Katyal, A.K.; Zhu, J.L.; Kremesec, V.J.; Hockman, E.L.

    1992-01-01

    Spills and leaks of hydrocarbons from underground storage tanks, pipelines and other facilities pose a serious potential for groundwater contamination which can be very costly to remediate. The severity of the impacts and the cost of remediation can be reduced by various means. Lateral spreading of free phase hydrocarbons on the groundwater table can be prevented by pumping water to control the hydraulic gradient. Recovery of floating product may be performed by skimming hydrocarbons from wells, usually in combination with water pumping to increase the gradient. The environmental variables (water table gradient, water table fluctuations due to regional recovery wells, rates of water pumping)

  13. Beaver Mediated Water Table Dynamics in Mountain Peatlands

    Science.gov (United States)

    Karran, D. J.; Westbrook, C.; Bedard-Haughn, A.

    2016-12-01

    Water table dynamics play an important role in the ecological and biogeochemical processes that regulate carbon and water storage in peatlands. Beaver are common in these habitats and the dams they build have been shown to raise water tables in other environments. However, the impact of beaver dams in peatlands, where water tables rest close to the surface, has yet to be determined. We monitored a network of 50 shallow wells in a Canadian Rocky Mountain peatland for 6 years. During this period, a beaver colony was maintaining a number of beaver ponds for four years until a flood event removed the colony from the area and breached some of the dams. Two more years of data were collected after the flood event to assess whether the dams enhanced groundwater storage. Beaver dams raised water tables just as they do in other environments. Furthermore, water tables within 100 meters of beaver dams were more stable than those further away and water table stability overall was greater before the flood event. Our results suggest the presence/absence of beaver in peatlands has implications for groundwater water storage and overall system function.

  14. Numerical tables. Physical and chemical analyses of Rhine water 1984

    International Nuclear Information System (INIS)

    1984-01-01

    Tables present the methods of analysis and the data obtained on inorganic, organic, and radioactive impurities in Rhine water. The measuring stations were located in Switzerland, France, West Germany, and the Netherlands. (HP) [de

  15. Pumping Drainage Well Layout and Optimum Capacity Design to Lower Groundwater Table in Urban Areas

    Directory of Open Access Journals (Sweden)

    Mojtaba Shourian

    2017-11-01

    Full Text Available High groundwater levels in urban areas pose major problems in construction and mining projects. A typical and effective solution in these situations is to dig drainage wells to lower the water table to the desired level through an appropriate pumping strategy. Although the method is efficient, the operating costs are relatively high and it is, therefore, of great importance to optimize the groundwater pumping system to save costs. In this paper, a simulation-based optimization approach is exploited to minimize the total costs through optimizing the layout and capacity of pumping wells. For this purpose, MODFLOW, the groundwater simulation software, is used to investigate aquifer behavior under pumping wells and the well-known Firefly Optimization Algorithm is exploited to find the optimal well layout and capacity. The proposed FOA-MODFLOW model is tested on the small urban ancient Grand Mosque region in Kerman City, southeast of Iran, to minimize the cost of the draining project. Experimental results indicate that the proposed cost-effective design noticeably outperforms the one proposed by the consulting engineers in terms of both the number of drilled wells and the associated pumping costs. The optimal strategy observes the constraints and demands by constructing only two wells with a total pumping rate of 5503 m3/day and a water table drawdown of more than 1.5 m provided the ground subsidence is within the allowable limit of less than 80 mm. Additionally, examination of the values obtained for the various design parameters shows that the proposed strategy is the best and its sensitivity to maximum permissible water level and pumping rates is highest as compared with other similar designs.

  16. Mechanism for migration of light nonaqueous phase liquids beneath the water table

    International Nuclear Information System (INIS)

    Krueger, J.P.; Portman, M.E.

    1991-01-01

    This paper reports on an interesting transport mechanism may account for the presence of light nonaqueous phase liquid (LNAPL) found beneath the water table in fine-grained aquifers. During the course of two separate site investigations related to suspected releases from underground petroleum storage tanks, LNAPL was found 7 to 10 feet below the regional water table. In both cases, the petroleum was present within a sand seam which was encompassed within a deposit of finer-grained sediments. The presence of LNAPL below the water table is uncommon; typically, LNAPL is found floating on the water table or on the capillary fringe. The occurrence of LNAPL below the water table could have resulted from fluctuating regional water levels which allowed the petroleum to enter the sand when the water table was a lower stage or, alternately, could have occurred as a result of the petroleum depressing the water table beneath the level of the sand. In fine-grained soils where the lateral migration rate is low, the infiltrating LNAPL may depress the water table to significant depth. The LNAPL may float on the phreatic surface with the bulk of its volume beneath the phreatic surface. Once present in the sand and surrounded by water-saturated fine-grained sediments, capillary forces prevent the free movement of the petroleum back across the boundary from the coarse-grained sediments to the fine-grained sediments. Tapping these deposits with a coarser grained filter packed monitoring well releases the LNAPL, which may accumulate to considerable thickness in the monitoring well

  17. Tables of the velocity of sound in sea water

    CERN Document Server

    Bark, L S; Meister, N A

    1964-01-01

    Tables of the Velocity of Sound in Sea Water contains tables of the velocity of sound in sea water computed on a ""Strela-3"" high-speed electronic computer and a T-5 tabulator at the Computational Center of the Academy of Sciences. Knowledge of the precise velocity of sound in sea water is of great importance when investigating sound propagations in the ocean and when solving practical problems involving the use of hydro-acoustic devices. This book demonstrates the computations made for the velocity of sound in sea water, which can be found in two ways: by direct measurement with the aid of s

  18. Risk evaluation of ground water table decline as a type of desertification. A case study are: Southern Iran

    Energy Technology Data Exchange (ETDEWEB)

    Asrari, E.; Masoudi, M.

    2009-07-01

    This paper presents a model to assess risk of ground water table decline. Taking into consideration eleven indicators of lowering of ground water table the model identifies areas with Potential Risk (risky zones) and areas of Actual risk as well as projects the probability of the worse degradation in future. (Author) 7 refs.

  19. Risk evaluation of ground water table decline as a type of desertification. A case study are: Southern Iran

    International Nuclear Information System (INIS)

    Asrari, E.; Masoudi, M.

    2009-01-01

    This paper presents a model to assess risk of ground water table decline. Taking into consideration eleven indicators of lowering of ground water table the model identifies areas with Potential Risk (risky zones) and areas of Actual risk as well as projects the probability of the worse degradation in future. (Author) 7 refs.

  20. Empirical method for simulation of water tables by digital computers

    International Nuclear Information System (INIS)

    Carnahan, C.L.; Fenske, P.R.

    1975-09-01

    An empirical method is described for computing a matrix of water-table elevations from a matrix of topographic elevations and a set of observed water-elevation control points which may be distributed randomly over the area of interest. The method is applicable to regions, such as the Great Basin, where the water table can be assumed to conform to a subdued image of overlying topography. A first approximation to the water table is computed by smoothing a matrix of topographic elevations and adjusting each node of the smoothed matrix according to a linear regression between observed water elevations and smoothed topographic elevations. Each observed control point is assumed to exert a radially decreasing influence on the first approximation surface. The first approximation is then adjusted further to conform to observed water-table elevations near control points. Outside the domain of control, the first approximation is assumed to represent the most probable configuration of the water table. The method has been applied to the Nevada Test Site and the Hot Creek Valley areas in Nevada

  1. Water table fluctuations and soil biogeochemistry: An experimental approach using an automated soil column system

    Science.gov (United States)

    Rezanezhad, F.; Couture, R.-M.; Kovac, R.; O'Connell, D.; Van Cappellen, P.

    2014-02-01

    Water table fluctuations significantly affect the biological and geochemical functioning of soils. Here, we introduce an automated soil column system in which the water table regime is imposed using a computer-controlled, multi-channel pump connected to a hydrostatic equilibrium reservoir and a water storage reservoir. The potential of this new system is illustrated by comparing results from two columns filled with 45 cm of the same homogenized riparian soil. In one soil column the water table remained constant at -20 cm below the soil surface, while in the other the water table oscillated between the soil surface and the bottom of the column, at a rate of 4.8 cm d-1. The experiment ran for 75 days at room temperature (25 ± 2 °C). Micro-sensors installed at -10 and -30 cm below the soil surface in the stable water table column recorded constant redox potentials on the order of 600 and -200 mV, respectively. In the fluctuating water table column, redox potentials at the same depths oscillated between oxidizing (∼700 mV) and reducing (∼-100 mV) conditions. Pore waters collected periodically and solid-phase analyses on core material obtained at the end of the experiment highlighted striking geochemical differences between the two columns, especially in the time series and depth distributions of Fe, Mn, K, P and S. Soil CO2 emissions derived from headspace gas analysis exhibited periodic variations in the fluctuating water table column, with peak values during water table drawdown. Transient redox conditions caused by the water table fluctuations enhanced microbial oxidation of soil organic matter, resulting in a pronounced depletion of particulate organic carbon in the midsection of the fluctuating water table column. Denaturing Gradient Gel Electrophoresis (DGGE) revealed the onset of differentiation of the bacterial communities in the upper (oxidizing) and lower (reducing) soil sections, although no systematic differences in microbial community structure

  2. Relationships between water table and model simulated ET

    Science.gov (United States)

    Prem B. Parajuli; Gretchen F. Sassenrath; Ying Ouyang

    2013-01-01

    This research was conducted to develop relationships among evapotranspiration (ET), percolation (PERC), groundwater discharge to the stream (GWQ), and water table fluctuations through a modeling approach. The Soil and Water Assessment Tool (SWAT) hydrologic and crop models were applied in the Big Sunflower River watershed (BSRW; 7660 km2) within the Yazoo River Basin...

  3. Nitrogen Uptake in Soils under Different Water Table Depths ...

    African Journals Online (AJOL)

    A mathematical model was used to examine the interactions of NH4 + transport to rice roots, as well as to calculate root length densities required to relate N uptake to concentrations of NH4 + in solution around the rooting medium for three water treatments: water table 30 cm below the surface, 15 cm below the surface and ...

  4. Effect of water table dynamics on land surface hydrologic memory

    Science.gov (United States)

    Lo, Min-Hui; Famiglietti, James S.

    2010-11-01

    The representation of groundwater dynamics in land surface models has received considerable attention in recent years. Most studies have found that soil moisture increases after adding a groundwater component because of the additional supply of water to the root zone. However, the effect of groundwater on land surface hydrologic memory (persistence) has not been explored thoroughly. In this study we investigate the effect of water table dynamics on National Center for Atmospheric Research Community Land Model hydrologic simulations in terms of land surface hydrologic memory. Unlike soil water or evapotranspiration, results show that land surface hydrologic memory does not always increase after adding a groundwater component. In regions where the water table level is intermediate, land surface hydrologic memory can even decrease, which occurs when soil moisture and capillary rise from groundwater are not in phase with each other. Further, we explore the hypothesis that in addition to atmospheric forcing, groundwater variations may also play an important role in affecting land surface hydrologic memory. Analyses show that feedbacks of groundwater on land surface hydrologic memory can be positive, negative, or neutral, depending on water table dynamics. In regions where the water table is shallow, the damping process of soil moisture variations by groundwater is not significant, and soil moisture variations are mostly controlled by random noise from atmospheric forcing. In contrast, in regions where the water table is very deep, capillary fluxes from groundwater are small, having limited potential to affect soil moisture variations. Therefore, a positive feedback of groundwater to land surface hydrologic memory is observed in a transition zone between deep and shallow water tables, where capillary fluxes act as a buffer by reducing high-frequency soil moisture variations resulting in longer land surface hydrologic memory.

  5. Geostatistical investigation into the temporal evolution of spatial structure in a shallow water table

    Directory of Open Access Journals (Sweden)

    S. W. Lyon

    2006-01-01

    during many rain events. During the summer, when evaporation exceeds precipitation, the ranges of the indicator semivariograms decreased during rainfall events due to isolated responses in the water table. For the longer, monthly time interval, semivariograms exhibited higher sills and shorter ranges during spring and lower sills and longer ranges during the summer. For this long time interval, there was a good correlation between probability of exceeding the time-variable median water table and the soil topographical wetness index during the spring. Indicator kriging incorporating both the short and long time interval structure of the shallow water table (hard and soft data, respectively provided more realistic maps that agreed better with actual observations than the hard data alone. This technique to represent both event-based and seasonal trends incorporates the hillslope-scale hydrological processes to capture significant patterns in the shallow water table. Geostatistical analysis of the spatial and temporal evolution of the shallow water table gives information about the formation of saturated areas important in the understanding hydrological processes working at this and other hillslopes.

  6. Microtropography and water table fluctuation in a sphagnum mire

    Science.gov (United States)

    E.S. Verry

    1984-01-01

    A detailed organic soil profile description, 22 years of continuous water table records, and a hummock-hollow level survey were examined at a small Minnesota mire (a bog with remnants of poor fen vegetation). Variation in the level survey suggests that hollows be used to minimize variation when detailed topographic information is needed and to match profile...

  7. Modelling mid-span water table depth and drainage discharge ...

    African Journals Online (AJOL)

    2015-04-03

    Apr 3, 2015 ... were monitored in 1.7 m deep piezometers installed mid-way between two drains by using an electronic .... logical components in soils with shallow water tables. ..... dency of neither under-estimating nor over-estimating DDs,.

  8. Distribution Channel Intensity among Table Water Producers in Nigeria

    Directory of Open Access Journals (Sweden)

    Joseph Edewor Agbadudu

    2017-09-01

    Full Text Available Planning for and making reasonable decisions regarding reaching the target market with an organization’s product is a critical task on the part of management, which involves a careful evaluation and selection of its channel structure and intensity.This study therefore examines distribution channel intensity among table water producers in Edo State, Nigeria. The focus of the study is to ascertain the variables that significantly predict distribution intensity among the firms in the table water industry in Edo State. The study seeks to proffer answer to fundamental question of why brands within a single category of a given consumer good differ significantly in their distribution intensity. Using a survey research design, the data used for this study were obtained by taking a sample of 110 table water firms within the three senatorial districts in the State. The data obtained were presented and analyzed using different statistical tools such as mean and multiple regression through Statistical Packages for Social Sciences (SPSS version 22 software. Findings revealed that manufacturers’ target focus, manufacturers’ support program, brand quality and level of firm’s technological advancement were significant predictors of distribution channel intensity among the industrial players in table water industry in the State. Based on the findings, the study recommended that table water firms within the State can secure a competitive edge over their fellow counterpart in the industry by designing an optimal distribution intensity that will meet up their marketing objectives. It is also recommended that the adoption of modern technology in form of online sales is an efficient way of sales and distribution which could be used to enhance their distribution techniques if there is a need to cut down on middle men due to increased cost. The study concluded that optimal distribution intensity could be achieved not by mere imitation of competitors but through

  9. Digital subtraction angiography of lower limb arteries using and automatic table translation. Feasibility. Preliminary results

    International Nuclear Information System (INIS)

    Seka, R.; Amiel, M.; Boller, A.; Chapelon, C.; Clermont, A.; Revel, D.; Pinet, F.

    1988-01-01

    Digital subtraction angiography (DSA) as a method of evaluating lower limb arteries required examination of one limb at a time up to now. Moreover repeated injections of contrast material were necessary. This problem was mainly due to the relative small image intensifier field available and to the difficulty of repositionning the patient between mask and image acquisition. The preliminary results obtained with 24 patients studied on angiographic unit equipped with: a DSA system (DG 300-CGR) using 512x512 matrix size, an angiographic table (Angix M 200) allowing an automatic sequantial translation, a removable image intensifier using a 16 inch field below the table, are reported. Thus, all those characteristics allow DSA of lower limb arteries. Only one injection of contrast material (Ioxaglate: 80 ml at 8-10 ml/second) was used per procedure. This, usually, allows good quality examination of lower limb arteries [fr

  10. Water tables constrain height recovery of willow on Yellowstone's northern range.

    Science.gov (United States)

    Bilyeu, Danielle M; Cooper, David J; Hobbs, N Thompson

    2008-01-01

    Excessive levels of herbivory may disturb ecosystems in ways that persist even when herbivory is moderated. These persistent changes may complicate efforts to restore ecosystems affected by herbivores. Willow (Salix spp.) communities within the northern range in Yellowstone National Park have been eliminated or degraded in many riparian areas by excessive elk (Cervus elaphus L.) browsing. Elk browsing of riparian willows appears to have diminished following the reintroduction of wolves (Canis lupis L.), but it remains uncertain whether reduced herbivory will restore willow communities. The direct effects of elk browsing on willows have been accompanied by indirect effects from the loss of beaver (Castor canadensis Kuhl) activity, including incision of stream channels, erosion of fine sediments, and lower water tables near streams historically dammed by beaver. In areas where these changes have occurred, lowered water tables may suppress willow height even in the absence of elk browsing. We conducted a factorial field experiment to understand willow responses to browsing and to height of water tables. After four years of protection from elk browsing, willows with ambient water tables averaged only 106 cm in height, with negligible height gain in two of three study species during the last year of the experiment. Willows that were protected from browsing and had artificially elevated water tables averaged 147 cm in height and gained 19 cm in the last year of the experiment. In browsed plots, elevated water tables doubled height gain during a period of slightly reduced browsing pressure. We conclude that water availability mediates the rate of willow height gain and may determine whether willows grow tall enough to escape the browse zone of elk and gain resistance to future elk browsing. Consequently, in areas where long-term beaver absence has resulted in incised stream channels and low water tables, a reduction in elk browsing alone may not be sufficient for recovery

  11. Future water table rise at Yucca Mountain: A regulatory perspective

    International Nuclear Information System (INIS)

    Coleman, N.M.

    1995-01-01

    The U.S. Nuclear Regulatory Commission staff has developed a program of Systematic Regulatory Analysis (SRA). The purpose of this program is to ensure that important technical issues related to compliance with 10 CFR Part 60 will be identified before receipt of a license application. A plan is being developed to review the U.S. Department of Energy's (DOE's) demonstration of compliance in the license application for each part of the regulation. Under the siting criteria of NRC's Part 60, one of the potentially adverse conditions is the possibility that the water table may rise high enough to saturate a repository in the unsaturated zone. DOE must evaluate this and other conditions in a license application for a geologic repository site. DOE's evaluation must show compliance with the requirements of Part 60 with reasonable assurance. This paper describes the NRC staff's preliminary plans to review DOE's demonstration of compliance, including assumptions about a future rise of the water table

  12. Stochastic estimation of plant-available soil water under fluctuating water table depths

    Science.gov (United States)

    Or, Dani; Groeneveld, David P.

    1994-12-01

    Preservation of native valley-floor phreatophytes while pumping groundwater for export from Owens Valley, California, requires reliable predictions of plant water use. These predictions are compared with stored soil water within well field regions and serve as a basis for managing groundwater resources. Soil water measurement errors, variable recharge, unpredictable climatic conditions affecting plant water use, and modeling errors make soil water predictions uncertain and error-prone. We developed and tested a scheme based on soil water balance coupled with implementation of Kalman filtering (KF) for (1) providing physically based soil water storage predictions with prediction errors projected from the statistics of the various inputs, and (2) reducing the overall uncertainty in both estimates and predictions. The proposed KF-based scheme was tested using experimental data collected at a location on the Owens Valley floor where the water table was artificially lowered by groundwater pumping and later allowed to recover. Vegetation composition and per cent cover, climatic data, and soil water information were collected and used for developing a soil water balance. Predictions and updates of soil water storage under different types of vegetation were obtained for a period of 5 years. The main results show that: (1) the proposed predictive model provides reliable and resilient soil water estimates under a wide range of external conditions; (2) the predicted soil water storage and the error bounds provided by the model offer a realistic and rational basis for decisions such as when to curtail well field operation to ensure plant survival. The predictive model offers a practical means for accommodating simple aspects of spatial variability by considering the additional source of uncertainty as part of modeling or measurement uncertainty.

  13. Estimating drain flow from measured water table depth in layered soils under free and controlled drainage

    Science.gov (United States)

    Saadat, Samaneh; Bowling, Laura; Frankenberger, Jane; Kladivko, Eileen

    2018-01-01

    Long records of continuous drain flow are important for quantifying annual and seasonal changes in the subsurface drainage flow from drained agricultural land. Missing data due to equipment malfunction and other challenges have limited conclusions that can be made about annual flow and thus nutrient loads from field studies, including assessments of the effect of controlled drainage. Water table depth data may be available during gaps in flow data, providing a basis for filling missing drain flow data; therefore, the overall goal of this study was to examine the potential to estimate drain flow using water table observations. The objectives were to evaluate how the shape of the relationship between drain flow and water table height above drain varies depending on the soil hydraulic conductivity profile, to quantify how well the Hooghoudt equation represented the water table-drain flow relationship in five years of measured data at the Davis Purdue Agricultural Center (DPAC), and to determine the impact of controlled drainage on drain flow using the filled dataset. The shape of the drain flow-water table height relationship was found to depend on the selected hydraulic conductivity profile. Estimated drain flow using the Hooghoudt equation with measured water table height for both free draining and controlled periods compared well to observed flow with Nash-Sutcliffe Efficiency values above 0.7 and 0.8 for calibration and validation periods, respectively. Using this method, together with linear regression for the remaining gaps, a long-term drain flow record for a controlled drainage experiment at the DPAC was used to evaluate the impacts of controlled drainage on drain flow. In the controlled drainage sites, annual flow was 14-49% lower than free drainage.

  14. Influence of water table decline on growth allocation and endogenous gibberellins in black cottonwood

    Energy Technology Data Exchange (ETDEWEB)

    Rood, S.B.; Zanewich, K.; Stefura, C. [Lethbridge Univ., Lethbridge, AB (Canada). Dept. of Biological Sciences; Mahoney, J.M. [Alberta Environmental Protection, Lethbridge, AB (Canada)

    2000-06-01

    Cottonwoods have shown an adaptation to the riparian zone by coordinating root elongation to maintain contact with the water table, whose depth varies with the elevation of the adjacent river. The rate of water decline on growth allocation and concentrations of endogenous gibberellins (GAs) in black cottonwood saplings were studied at the University of Lethbridge, Alberta. Water declines were achieved by using rhizopods, and root elongation approximately doubled in response whereas leaf area was reduced. At some point, a greater water decline rate led to water stress resulting in reduced growth, increased leaf diffusive resistance, decreased water potential, and leaf senescence and abscission. After extraction of endogenous GAs, they were purified and analysed by gas chromatography-selected ion monitoring with internal ({sup 2}H{sub 2})GA standards. The results showed that GAs were higher in shoot tips and sequentially lower in basal stems, root tips, leaves and upper roots. Noticeable relationships did not appear between GA concentration and growth allocation across the water decline treatments. Only GA{sub 8} showed a consistent reduction in plants experiencing water table decline. This research did not permit the authors to conclude whether endogenous GAs play a primary role in the regulation of root elongation in response to water table decline. 7 figs., 25 refs.

  15. Water table monitoring in a mined riparian zone

    Directory of Open Access Journals (Sweden)

    Thomaz Marques Cordeiro Andrade

    2010-04-01

    Full Text Available The objective of this study was to test an easily fabricated tool that assist in the manual installation of piezometers, as well as water table monitor in the research site, located at the Gualaxo do Norte River Watershed, state of Minas Gerais, Brazil. The tool is made of iron pipes and is a low-cost alternative for shallow groundwater observation wells. The measurements were done in a riparian zone after being gold mined, when vegetation and upper soil layers were removed. The wells were installed in three areas following a transect from the river bank. The method was viable for digging up to its maximum depth of 3 meters in a low resistance soil and can be improved to achieve a better resistance over impact and its maximum depth of perforation. Water table levels varied distinctly according to its depth in each point. It varies most in the more shallow wells in different areas, while it was more stable in the deeper ones. The water table profile reflected the probably profile f the terrain and can be a reference for its leveling in reconstitution of degraded banks where upper layers of the soil were removed. Groundwater monitoring can be also an indicator of the suitability of the substrate for soil reconstitution in terms of the maintenance of an infiltration capacity similar to the original material.

  16. Stochastic analysis of unsaturated steady flows above the water table

    Science.gov (United States)

    Severino, Gerardo; Scarfato, Maddalena; Comegna, Alessandro

    2017-08-01

    Steady flow takes place into a three-dimensional partially saturated porous medium where, due to their spatial variability, the saturated conductivity Ks, and the relative conductivity Kr are modeled as random space functions (RSF)s. As a consequence, the flow variables (FVs), i.e., pressure-head and specific flux, are also RSFs. The focus of the present paper consists into quantifying the uncertainty of the FVs above the water table. The simple expressions (most of which in closed form) of the second-order moments pertaining to the FVs allow one to follow the transitional behavior from the zone close to the water table (where the FVs are nonstationary), till to their far-field limit (where the FVs become stationary RSFs). In particular, it is shown how the stationary limits (and the distance from the water table at which stationarity is attained) depend upon the statistical structure of the RSFs Ks, Kr, and the infiltrating rate. The mean pressure head >> has been also computed, and it is expressed as =Ψ0>(1+ψ>), being ψ a characteristic heterogeneity function which modifies the zero-order approximation Ψ0 of the pressure head (valid for a vadose zone of uniform soil properties) to account for the spatial variability of Ks and Kr. Two asymptotic limits, i.e., close (near field) and away (far field) from the water table, are derived into a very general manner, whereas the transitional behavior of ψ between the near/far field can be determined after specifying the shape of the various input soil properties. Besides the theoretical interest, results of the present paper are useful for practical purposes, as well. Indeed, the model is tested against to real data, and in particular it is shown how it is possible for the specific case study to grasp the behavior of the FVs within an environment (i.e., the vadose zone close to the water table) which is generally very difficult to access by direct inspection.

  17. Changes in vegetative communities and water table dynamics following timber harvesting in small headwater streams

    Science.gov (United States)

    B. Choi; J.C. Dewey; J. A. Hatten; A.W. Ezell; Z. Fan

    2012-01-01

    In order to better understand the relationship between vegetation communities and water table in the uppermost portions (ephemeral–intermittent streams) of headwater systems, seasonal plot-based field characterizations of vegetation were used in conjunction with monthly water table measurements. Vegetation, soils, and water table data were examined to determine...

  18. Response of anaerobic carbon cycling to water table manipulation in an Alaskan rich fen

    Science.gov (United States)

    Kane, E.S.; Chivers, M.R.; Turetsky, M.R.; Treat, C.C.; Petersen, D.G.; Waldrop, M.; Harden, J.W.; McGuire, A.D.

    2013-01-01

    To test the effects of altered hydrology on organic soil decomposition, we investigated CO2 and CH4 production potential of rich-fen peat (mean surface pH = 6.3) collected from a field water table manipulation experiment including control, raised and lowered water table treatments. Mean anaerobic CO2 production potential at 10 cm depth (14.1 ± 0.9 μmol C g−1 d−1) was as high as aerobic CO2 production potential (10.6 ± 1.5 μmol C g−1 d−1), while CH4 production was low (mean of 7.8 ± 1.5 nmol C g−1 d−1). Denitrification enzyme activity indicated a very high denitrification potential (197 ± 23 μg N g−1 d−1), but net NO-3 reduction suggested this was a relatively minor pathway for anaerobic CO2 production. Abundances of denitrifier genes (nirK and nosZ) did not change across water table treatments. SO2-4 reduction also did not appear to be an important pathway for anaerobic CO2 production. The net accumulation of acetate and formate as decomposition end products in the raised water table treatment suggested that fermentation was a significant pathway for carbon mineralization, even in the presence of NO-3. Dissolved organic carbon (DOC) concentrations were the strongest predictors of potential anaerobic and aerobic CO2 production. Across all water table treatments, the CO2:CH4 ratio increased with initial DOC leachate concentrations. While the field water table treatment did not have a significant effect on mean CO2 or CH4 production potential, the CO2:CH4 ratio was highest in shallow peat incubations from the drained treatment. These data suggest that with continued drying or with a more variable water table, anaerobic CO2 production may be favored over CH4 production in this rich fen. Future research examining the potential for dissolved organic substances to facilitate anaerobic respiration, or alternative redox processes that limit the effectiveness of organic acids as substrates in anaerobic metabolism, would help explain additional

  19. Water table and overbank flow frequency changes due to suburbanization-induced channel incision, Virginia Coastal Plain, USA

    Science.gov (United States)

    Hancock, G.; Mattell, N.; Christianson, E.; Wacksman, J.

    2004-12-01

    Channel incision is a widely observed response to increased flow in urbanized watersheds, but the effects of channel lowering on riparian water tables is not well documented. In a rapidly incising suburban stream in the Virginia Coastal Plain, we hypothesize that incision has lowered floodplain water tables and decreased the overbank flow frequency, and suggest these changes impact vegetation distribution in a diverse, protected riparian habitat. The monitored stream is a tributary to the James River draining 1.3 km2, of which 15% is impervious cover. Incision has occurred largely through upstream migration of a one m high knickpoint at a rate of 1-2 m/yr, primarily during high flow events. We installed 33 wells in six floodplain transects to assess water table elevations beneath the floodplain adjacent to the incising stream. To document the impacts of incision, two transects are located 30 and 50 m upstream of the knickpoint in unincised floodplain, and the remainder are 5, 30, 70, and 100 m downstream of the knickpoint in incised floodplain. In one transect above and two below, pressure transducers attached to dataloggers provide a high-resolution record of water table response to storm events. Significant differences have been observed in the water table above and below the knickpoint. Above the knickpoint, the water table is relatively flat and is 0.2-0.4 m below the floodplain surface. Water table response to precipitation events is nearly immediate, with the water table rising to the floodplain surface in significant rainfall events. In the transect immediately downstream of the knickpoint, the water table possesses a steep gradient, rising from ~1 m below the floodplain at the stream to 0.3 m below the surface within 20 m. In the most downstream transects, the water table is relatively flat, but is one m below the floodplain surface, equivalent to the depth of incision generated by knickpoint passage. Upstream of the knickpoint, overbank flooding occurs

  20. African Mahogany transpiration with Granier method and water table lysimeter

    Directory of Open Access Journals (Sweden)

    Ana C. O. Sérvulo

    Full Text Available ABSTRACT The thermal dissipation probe (Granier method is useful in the water deficit monitoring and irrigation management of African Mahogany, but its model needs proper adjustment. This paper aimed to adjust and validate the Granier sap flux model to estimate African Mahogany transpiration, measure transpiration using lysimeter and relate it to atmospheric water demand. Weather conditions, transpiration and sap flux were monitored in three units of 2.5-year-old African Mahogany trees in constant water table lysimeter, in Goiânia, GO. Sapwood area (SA, leaf area (LA, transpiration measured by lysimeter (TLYS and estimated by sap flux (TSF were evaluated. The SA comprised 55.24% of the trunk’s transversal section. The LA varied from 11.95 to 10.66 m2. TLYS and TSF varied from 2.94 to 29.31 and from 0.94 to 15.45 L d-1, respectively. The original model underestimated transpiration by 44.4%, being the adjusted equation F = 268.25 . k1.231. SA was significant (F < 0.05. Due the root confinement, the transpiration showed low correlation, but positive, with the atmospheric water demand.

  1. Optimization of irrigation water in stone fruit and table grapes

    Science.gov (United States)

    de la Rosa, Jose Mª; Castillo, Cristina; Temnani, Abdel; Pérez-Pastor, Alejandro

    2017-04-01

    In water scarcity areas, it must be highlighted that the maximum productions of the crops do not necessarily imply maximum profitability. Therefore, during the last years a special interest in the development of deficit irrigation strategies based on significant reductions of the seasonal ET without affecting production or quality has been observed. The strategies of regulated deficit irrigation (RDI) are based on the reduction of water supply during non critical periods, the covering of water needs during critical periods and maximizing, at the same time, the production by unit of applied water. The main objective of this experiment was to implement, demonstrate and disseminate a sustainable irrigation strategy based on deficit irrigation to promote its large scale acceptance and use in woody crops in Mediterranean agroecosystems, characterized by water scarcity, without affecting the quality standards demanded by exportation markets. Five demonstration plots were established in representative crops of the irrigating community of Campotejar (Murcia, Spain): i) Peach trees, cv. catherina in the "Periquitos" farm; ii) Apricot trees, cv. "Red Carlet" in "La Hoya del Fenazar" farm; iii) Nectarine trees, cv. Viowhite in "Agrícola Don Fernando" farm; iv) Table grape, cv "Crimson Seedless" in "La Hornera" farm; and v) Paraguayan cv. carioca in "The Hornera" farm. In each demonstration plot, at least two irrigation treatments were established: i) Control (CTL), irrigated to ensure non-limiting water conditions (120% of crop evapotranspiration) and ii) Regulated deficit irrigation (RDI) irrigated as CTL during critical periods and decreasing irrigation in non-critical periods. The plant water status indicators evaluated were midday stem water potential and Trunk Diameter Fluctuation derived indices: maximum daily shrinkage (MDS) and trunk daily growth rate (TGR); vegetative growth of the different crops from trunk diameter and pruning dry weight, fruit growth and fruit

  2. Modelling contrasting responses of wetland productivity to changes in water table depth

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2012-11-01

    Full Text Available Responses of wetland productivity to changes in water table depth (WTD are controlled by complex interactions among several soil and plant processes, and hence are site-specific rather than general in nature. Hydrological controls on wetland productivity were studied by representing these interactions in connected hummock and hollow sites in the ecosystem model ecosys, and by testing CO2 and energy fluxes from the model with those measured by eddy covariance (EC during years with contrasting WTD in a shrub fen at Lost Creek, WI. Modelled interactions among coupled processes for O2 transfer, O2 uptake, C oxidation, N mineralization, N uptake and C fixation by diverse microbial, root and mycorrhizal populations enabled the model to simulate complex responses of CO2 exchange to changes in WTD that depended on the WTD at which change was occurring. At the site scale, greater WTD caused the model to simulate greater CO2 influxes and effluxes over hummocks vs. hollows, as has been found at field sites. At the landscape scale, greater WTD caused the model to simulate greater diurnal CO2 influxes and effluxes under cooler weather when water tables were shallow, but also smaller diurnal CO2 influxes and effluxes under warmer weather when water tables were deeper, as was also apparent in the EC flux measurements. At an annual time scale, these diurnal responses to WTD in the model caused lower net primary productivity (NPP and heterotrophic respiration (Rh, but higher net ecosystem productivity (NEP = NPP − Rh, to be simulated in a cooler year with a shallower water table than in a warmer year with a deeper one. This difference in NEP was consistent with those estimated from gap-filled EC fluxes in years with different water tables at Lost Creek and at similar boreal fens elsewhere. In sensitivity tests of the model, annual NEP

  3. A time series approach to inferring groundwater recharge using the water table fluctuation method

    Science.gov (United States)

    Crosbie, Russell S.; Binning, Philip; Kalma, Jetse D.

    2005-01-01

    The water table fluctuation method for determining recharge from precipitation and water table measurements was originally developed on an event basis. Here a new multievent time series approach is presented for inferring groundwater recharge from long-term water table and precipitation records. Additional new features are the incorporation of a variable specific yield based upon the soil moisture retention curve, proper accounting for the Lisse effect on the water table, and the incorporation of aquifer drainage so that recharge can be detected even if the water table does not rise. A methodology for filtering noise and non-rainfall-related water table fluctuations is also presented. The model has been applied to 2 years of field data collected in the Tomago sand beds near Newcastle, Australia. It is shown that gross recharge estimates are very sensitive to time step size and specific yield. Properly accounting for the Lisse effect is also important to determining recharge.

  4. Water-table fluctuations in the Amargosa Desert, Nye County, Nevada

    International Nuclear Information System (INIS)

    Paces, James B.; Whelan, Joseph

    2001-01-01

    Pleistocene ground-water discharge deposits approximately 20 km southwest of Yucca Mountain were previously thought to represent pluvial water-table rises of 80 to 120 m. Data from new boreholes at two of the three discharge sites indicate that the modern water-table is at depths of only 17 to 30 m and that this shallow water is part of the regional ground-water flow system rather than being perched. Calcite in equilibrium with this modern ground water would have isotopic compositions similar to those in Pleistocene calcite associated with the discharge deposits. Carbon and uranium isotopes in both ground water and discharge deposits imply that past discharge consisted of a mixture of both shallow and deep ground water. These data limit Pleistocene water-table fluctuations at the specified Amargosa Desert discharge sites to between 17 and 30 m and eliminate the need to invoke large water-table rises

  5. The impact of water table drawdown and drying on subterranean aquatic fauna in in-vitro experiments.

    Directory of Open Access Journals (Sweden)

    Christine Stumpp

    Full Text Available The abstraction of groundwater is a global phenomenon that directly threatens groundwater ecosystems. Despite the global significance of this issue, the impact of groundwater abstraction and the lowering of groundwater tables on biota is poorly known. The aim of this study is to determine the impacts of groundwater drawdown in unconfined aquifers on the distribution of fauna close to the water table, and the tolerance of groundwater fauna to sediment drying once water levels have declined. A series of column experiments were conducted to investigate the depth distribution of different stygofauna (Syncarida and Copepoda under saturated conditions and after fast and slow water table declines. Further, the survival of stygofauna under conditions of reduced sediment water content was tested. The distribution and response of stygofauna to water drawdown was taxon specific, but with the common response of some fauna being stranded by water level decline. So too, the survival of stygofauna under different levels of sediment saturation was variable. Syncarida were better able to tolerate drying conditions than the Copepoda, but mortality of all groups increased with decreasing sediment water content. The results of this work provide new understanding of the response of fauna to water table drawdown. Such improved understanding is necessary for sustainable use of groundwater, and allows for targeted strategies to better manage groundwater abstraction and maintain groundwater biodiversity.

  6. Light water reactor lower head failure analysis

    International Nuclear Information System (INIS)

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L.

    1993-10-01

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response

  7. Light water reactor lower head failure analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)] [and others

    1993-10-01

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response.

  8. Numerical tables on physical and chemical analyses of Rhine water

    International Nuclear Information System (INIS)

    1982-01-01

    Tables on the places of measurement, the sampling methods and the methods of analysis used. The numerical tables of the measurement results are broken down in general parameters, organic, entrophicating and anorganic substances, orgnic micro-pollutants and radioactivity. (GG) [de

  9. Measuring the Change in Water Table with Gravity Methods - a Controlled Experiment

    DEFF Research Database (Denmark)

    Lund, S; Christiansen, Lars; Andersen, O. B.

    2009-01-01

    Gravity changes linearly with the change in soil water content. With the GRACE satellite mission the interest for ground-based gravity methods in hydrology has gained new attention. Time-lapse gravity data have the potential to constrain hydrological model parameters in a calibration scheme....... The greatest potential is seen for specific yield. The gravity signal from hydrology is small (10^-8 m/s^2 level) and the application of ground-based methods is mainly limited by the sensitivity of available instruments. In order to demonstrate the ability of the Scintrex CG-5 gravity meter to detect a change...... in water content, a controlled experiment was set up in 30 m by 20 m basin. The water table was lowered 0.69 m within 1½ hours and the corresponding gravity signal measured using two different approaches: a time series measurements at one location and a gravity network measurement including four points...

  10. Ground Water Recharge Estimation Using Water Table Fluctuation Method And By GIS Applications

    Science.gov (United States)

    Vajja, V.; Bekkam, V.; Nune, R.; M. v. S, R.

    2007-05-01

    Quite often it has become a debating point that how much recharge is occurring to the groundwater table through rainfall on one hand and through recharge structures such as percolation ponds and checkdams on the other. In the present investigations Musi basin of Andhra Pradesh, India is selected for study during the period 2005-06. Pre-monsoon and Post-monsoon groundwater levels are collected through out the Musi basin at 89 locations covering an area11, 291.69 km2. Geology of the study area and rainfall data during the study period has been collected. The contour maps of rainfall and the change in groundwater level between Pre-monsoon and Post- monsoon have been prepared. First the change in groundwater storage is estimated for each successive strips of areas enclosed between two contours of groundwater level fluctuations. In this calculation Specific yield (Sy) values are adopted based on the local Geology. Areas between the contours are estimated through Arc GIS software package. All such storages are added to compute the total storage for the entire basin. In order to find out the percent of rainfall converted into groundwater storage as well as to find out the ground water recharge due to storageponds, a contour map of rainfall for the study area is prepared and areas between successive contours have been calculated. Based on the Geology map, Infiltration values are adopted for each successive strip of the contour area. Then the amount of water infiltrated into the ground is calculated by adjusting the infiltration values for each strip, so that the total infiltrated water for the entire basin is matched with change in Ground water storage, which is 1314.37 MCM for the upper Musi basin while it is 2827.29 MCM for entire Musi basin. With this procedure on an average 29.68 and 30.66 percent of Rainfall is converted into Groundwater recharge for Upper Musi and for entire Musi basin respectively. In the total recharge, the contribution of rainfall directly to

  11. [Effects of water table manipulation on leaf photosynthesis, morphology and growth of Phragmites australis and Imperata cylindrica in the reclaimed tidal wetland at Dongtan of Chongming Island, China].

    Science.gov (United States)

    Zhong, Qi-Cheng; Wang, Jiang-Tao; Zhou, Jian-Hong; Ou, Qiang; Wang, Kai-Yun

    2014-02-01

    During the growing season of 2011, the leaf photosynthesis, morphological and growth traits of Phragmites australis and Imperata cylindrica were investigated along a gradient of water table (low, medium and high) in the reclaimed tidal wetland at the Dongtan of Chongming Island in the Yangtze Estuary of China. A series of soil factors, i. e., soil temperature, moisture, salinity and inorganic nitrogen content, were also measured. During the peak growing season, leaf photosynthetic capacity of P. australis in the wetland with high water table was significantly lower than those in the wetland with low and medium water tables, and no difference was observed in leaf photosynthetic capacity of I. cylindrica at the three water tables. During the entire growing season, at the shoot level, the morphological and growth traits of P. australis got the optimum in the wetland with medium water table, but most of the morphological and growth traits of I. cylindrica had no significant differences at the three water tables. At the population level, the shoot density, leaf area index and aboveground biomass per unit area were the highest in the wetland with high water table for P. australis, but all of the three traits were the highest in the wetland with low water table for I. cylindrica. At the early growing season, the rhizome biomass of P. australis in the 0-20 cm soil layer had no difference at the three water tables, and the rhizome biomass of I. cylindrica in the 0-20 cm soil layer in the wetland with high water table was significantly lower than those in the wetland with low and medium water table. As a native hygrophyte before the reclamation, the variations of performances of P. australis at the three water tables were probably attributed to the differences in the soil factors as well as the intensity of competition from I. cylindrica. To appropriately manipulate water table in the reclaimed tidal wetland may restrict the growth and propagation of the mesophyte I

  12. Changes in water table elevation at Yucca Mountain in response to seismic events

    International Nuclear Information System (INIS)

    Arnold, B.W.

    1996-01-01

    Investigation of mechanisms which could significantly alter the elevation of the water table at Yucca Mountain are motivated by the potential impacts such an occurrence would have on the performance of a high-level radioactive waste repository. In particular, we would like to evaluate the possibility of flooding a repository by water-table excursions. Changes in the water table could occur as relatively transient phenomena in response to seismic events by the seismic pumping mechanism. Quantitative evaluation of possible fluctuations of groundwater following earthquakes was undertaken in support of performance assessment calculations including seismicity

  13. Numerical tables on physical and chemical analyses of Rhine water 1983

    International Nuclear Information System (INIS)

    1984-01-01

    The numerical tables contain the measuring results of the physical-chemical studies on the Rhine water for the year 1983. The tables are arranged by general parameters, organic matter, eutrophicating substances, anorganic matter, metals, organic micropollution as well as by radioactivity (total alpha- or beta- and T-activity). (MM) [de

  14. The effect of changing water table on methane fluxes at two Finnish mire sites

    International Nuclear Information System (INIS)

    Martikainen, P.J.; Nykaenen, H.; Crill, P.; Silvola, J.

    1992-01-01

    Methane fluxes were measured using static chamber technique on a minerotrophic fen and an ombrotrophic peat bog site located in the Lakkasuo mire complex in central Finland. Both sites consisted of a virgin area and an area drained in 1961 by ditching. The measurements in 1991 were made biweekly from spring thaw to winter freezing. During this period, the mean CH4 emission from the virgin minerotrophic site and virgin ombrotrophic site was 98 mg/m -2 d -1 and 40 mg/m -2 d -1 , respectively. The mean emission of CH 4 from the drained ombrotrophic site was 18 mg/m -2 d -1 . The drained minerotrophic site consumed methane during most of the measuring period, the average uptake was 0.13 mg/m2d. Draining had lowered the average water table by 4 cm at the ombrotrophic site and by 20 cm at minerotrophic site. The possible reasons for the different development of the water table and methane fluxes at ombrotrophic and minerotrophic sites after drainer are discussed

  15. Lower internals for pressurized water reactor

    International Nuclear Information System (INIS)

    Chevereau, G.; Babin, M.

    1989-01-01

    The lower internals for PWR has a separating plate mounted beneath its lower core plate and defining a distribution chamber with it, peripheral mechanical connectors joining the plates separated by coolant passage and apertures in the separation plate connected to a coolant pipe [fr

  16. Effect of water table fluctuations on phreatophytic root distribution.

    Science.gov (United States)

    Tron, Stefania; Laio, Francesco; Ridolfi, Luca

    2014-11-07

    The vertical root distribution of riparian vegetation plays a relevant role in soil water balance, in the partition of water fluxes into evaporation and transpiration, in the biogeochemistry of hyporheic corridors, in river morphodynamics evolution, and in bioengineering applications. The aim of this work is to assess the effect of the stochastic variability of the river level on the root distribution of phreatophytic plants. A function describing the vertical root profile has been analytically obtained by coupling a white shot noise representation of the river level variability to a description of the dynamics of root growth and decay. The root profile depends on easily determined parameters, linked to stream dynamics, vegetation and soil characteristics. The riparian vegetation of a river characterized by a high variability turns out to have a rooting system spread over larger depths, but with shallower mean root depths. In contrast, a lower river variability determines root profiles with higher mean root depths. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Contribution of vegetation and water table on isoprene emission from boreal peatland microcosms

    DEFF Research Database (Denmark)

    Tiiva, Päivi; Faubert, Patrick; Räty, Sanna

    2009-01-01

    emission in these naturally wet ecosystems, although water table is predicted to decline due to climate warming. We studied the relative contribution of mosses vs. vascular plants to isoprene emission in boreal peatland microcosms in growth chambers by removing either vascular vegetation or both vascular...... hollows with intact vegetation, 45 ± 6 µg m-2 h-1, was decreased by 25% under water table drawdown. However, water table drawdown reduced net ecosystem carbon dioxide (CO2) exchange more dramatically than isoprene emission. Isoprene emission strongly correlated with both CO2 exchange and methane emission......Boreal peatlands are substantial sources of isoprene, a reactive hydrocarbon. However, it is not known how much mosses, vascular plants and peat each contribute to isoprene emission from peatlands. Furthermore, there is no information on the effects of declining water table depth on isoprene...

  18. Diffusive-dispersive mass transfer in the capillary fringe: Impact of water table fluctuations and heterogeneities

    DEFF Research Database (Denmark)

    Grathwohl, Peter; Haberer, Cristina; Ye, Yu

    Diffusive–dispersive mass transfer in the capillary fringe is important for many groundwater quality issues such as transfer of volatile compounds into (and out of) the groundwater, the supply of oxygen for aerobic degradation of hydrocarbons as well as for precipitation of minerals (e.g. iron...... hydroxides). 2D-laboratory scale experiments were used to investigate the transfer of oxygen into groundwater under non-reactive and reactive conditions, at steady state and with water table fluctuations. Results show that transfer of oxygen is limited by transverse dispersion in the capillary fringe...... and the dispersion coefficients are the same as below the water table. Water table fluctuations cause temporarily increased fluxes of oxygen into groundwater during draining conditions and entrapped air after water table rise. High-permeability inclusions in the capillary fringe enhance mass transfer of oxygen...

  19. Water property lookup table (sanwat) for use with the two-phase computational code shaft

    International Nuclear Information System (INIS)

    Sherman, M.P.; Eaton, R.R.

    1980-10-01

    A lookup table for water thermodynamic and transport properties (SANWAT) has been constructed for use with the two-phase computational code, SHAFT. The table, which uses density and specific internal energy as independent variables, covers the liquid, two-phase, and vapor regions. The liquid properties of water are contained in a separate subtable in order to obtain high accuracy for this nearly incompressible region that is frequently encountered in studies of the characteristics of nuclear-waste repositories

  20. Water table tests of proposed heat transfer tunnels for small turbine vanes

    Science.gov (United States)

    Meitner, P. L.

    1974-01-01

    Water-table flow tests were conducted for proposed heat-transfer tunnels which were designed to provide uniform flow into their respective test sections of a single core engine turbine vane and a full annular ring of helicopter turbine vanes. Water-table tests were also performed for the single-vane test section of the core engine tunnel. The flow in the heat-transfer tunnels was shown to be acceptable.

  1. Enhancing Groundwater Cost Estimation with the Interpolation of Water Tables across the United States

    Science.gov (United States)

    Rosli, A. U. M.; Lall, U.; Josset, L.; Rising, J. A.; Russo, T. A.; Eisenhart, T.

    2017-12-01

    Analyzing the trends in water use and supply across the United States is fundamental to efforts in ensuring water sustainability. As part of this, estimating the costs of producing or obtaining water (water extraction) and the correlation with water use is an important aspect in understanding the underlying trends. This study estimates groundwater costs by interpolating the depth to water level across the US in each county. We use Ordinary and Universal Kriging, accounting for the differences between aquifers. Kriging generates a best linear unbiased estimate at each location and has been widely used to map ground-water surfaces (Alley, 1993).The spatial covariates included in the universal Kriging were land-surface elevation as well as aquifer information. The average water table is computed for each county using block kriging to obtain a national map of groundwater cost, which we compare with survey estimates of depth to the water table performed by the USDA. Groundwater extraction costs were then assumed to be proportional to water table depth. Beyond estimating the water cost, the approach can provide an indication of groundwater-stress by exploring the historical evolution of depth to the water table using time series information between 1960 and 2015. Despite data limitations, we hope to enable a more compelling and meaningful national-level analysis through the quantification of cost and stress for more economically efficient water management.

  2. Estimating steady-state evaporation rates from bare soils under conditions of high water table

    Science.gov (United States)

    Ripple, C.D.; Rubin, J.; Van Hylckama, T. E. A.

    1970-01-01

    A procedure that combines meteorological and soil equations of water transfer makes it possible to estimate approximately the steady-state evaporation from bare soils under conditions of high water table. Field data required include soil-water retention curves, water table depth and a record of air temperature, air humidity and wind velocity at one elevation. The procedure takes into account the relevant atmospheric factors and the soil's capability to conduct 'water in liquid and vapor forms. It neglects the effects of thermal transfer (except in the vapor case) and of salt accumulation. Homogeneous as well as layered soils can be treated. Results obtained with the method demonstrate how the soil evaporation rates·depend on potential evaporation, water table depth, vapor transfer and certain soil parameters.

  3. The impact of long-term changes in water table height on carbon cycling in sub-boreal peatlands

    Science.gov (United States)

    Pypker, T. G.; Moore, P. A.; Waddington, J. M.; Hribljan, J. A.; Ballantyne, D.; Chimner, R. A.

    2011-12-01

    Peatlands are a critical component in the global carbon (C) cycle because they have been slowly sequestering atmospheric greenhouse gases as peat since the last glaciation. Today, soil C stocks in peatlands are estimated to represent 224 to 455 Pg, equal to 12-30% of the global soil C pool. At present, peatlands are estimated to sequester 76 Tg C yr-1. The flux of C to and from peatlands is likely to respond to climate change, thereby influencing atmospheric C concentrations. Peatland C budgets are tightly linked to their hydrology, hence, it is critical we understand how changes in hydrology will affect the C budgets of peatlands. The main objective of the project was to determine how long-term changes in water table height affect CO2 and CH4 fluxes from three adjacent peatlands. This study took place in the Seney National Wildlife Refuge (SNWR) in the Upper Peninsula of Michigan. SNWR is home to the largest wetland drainage project in Michigan. In 1912, ditches and dikes were created in an effort to convert approximately 20,000 ha of peatland to agriculture. The ditches and dikes were unsuccessful in creating agricultural land, but they are still in place. The manipulation of water table heights provides an opportunity to research how long-term peat drying or wetting alters C cycling in peatlands. From May to November in 2009, 2010 and 2011, we monitored CO2 fluxes using eddy covariance and chamber techniques in three adjacent peatlands with lowered, relatively unaltered ("control") and raised water table heights. In 2011, we installed CH4 analyzers to continuously monitor CH4 fluxes at the sites with high and relatively unaltered water table heights. The results are compared across sites to determine how changes in water table height might affect C fluxes sub-boreal peatlands.

  4. Influence of the tension-saturated zone on contaminant migration in shallow water-table regimes

    International Nuclear Information System (INIS)

    Gillham, R.W.

    1982-01-01

    Groundwater discharge represents a major pathway for the return to the biosphere of contaminants that are released to the subsurface environment. An understanding of the transport processes in groundwater discharge zones is therefore an important consideration in pathway analyses associated with the environmental assessment of proposed waste-management facilities. Shallow water tables are a common characteristic of groundwater discharge zones, particularly in humid climatic regions. In this paper, the results of field tests, laboratory tests and numerical simulations are used to show that under shallow water-table conditions, the zone of tension saturation can result in a rapid and highly disproportionate water-table response to precipitation. It is further shown that this response can result in complex migration patterns that would not be predicted by the classical approaches to solute transport modelling and that the response could result in large and highly transient inputs to surface water

  5. Holes in the Bathtub: Water Table Dependent Services and Threshold Behavior in an Economic Model of Groundwater Extraction

    Science.gov (United States)

    Kirk-lawlor, N. E.; Edwards, E. C.

    2012-12-01

    be the case if only the benefits and costs of groundwater extraction were considered. This hole-in-the-bathtub model can motivate managers to consider the costs of the loss of such flows, which may be very costly (in terms of loss of environmental services, loss of access to surface water, etc.). Alternatively, the decision to maintain the water table at an elevation that sustains a threshold-dependent outflow may cause income loss from the imposition of lower groundwater extraction rates. Weighing the benefits of maintaining threshold-dependent flows (including non-market benefits) with the net benefits of increased extraction is an important step in a prudent water management framework. To illustrate the usefulness of the modified model in a joint economic-hydrologic context, we provide a short case study of the Ojos de San Pedro area of the Rio Loa Basin in northern Chile. Evidence indicates that a wetland and lacustrine environment and a village dependent on that environment disappeared due to water extraction for industrial use. We demonstrate how the key features of the model provide important insight in understanding the tradeoffs that were made in this case.

  6. Rapid response of hydrological loss of DOC to water table drawdown and warming in Zoige peatland: results from a mesocosm experiment.

    Science.gov (United States)

    Lou, Xue-Dong; Zhai, Sheng-Qiang; Kang, Bing; Hu, Ya-Lin; Hu, Li-Le

    2014-01-01

    A large portion of the global carbon pool is stored in peatlands, which are sensitive to a changing environment conditions. The hydrological loss of dissolved organic carbon (DOC) is believed to play a key role in determining the carbon balance in peatlands. Zoige peatland, the largest peat store in China, is experiencing climatic warming and drying as well as experiencing severe artificial drainage. Using a fully crossed factorial design, we experimentally manipulated temperature and controlled the water tables in large mesocosms containing intact peat monoliths. Specifically, we determined the impact of warming and water table position on the hydrological loss of DOC, the exported amounts, concentrations and qualities of DOC, and the discharge volume in Zoige peatland. Our results revealed that of the water table position had a greater impact on DOC export than the warming treatment, which showed no interactive effects with the water table treatment. Both DOC concentration and discharge volume were significantly increased when water table drawdown, while only the DOC concentration was significantly promoted by warming treatment. Annual DOC export was increased by 69% and 102% when the water table, controlled at 0 cm, was experimentally lowered by -10 cm and -20 cm. Increases in colored and aromatic constituents of DOC (measured by Abs(254 nm), SUVA(254 nm), Abs(400 nm), and SUVA(400 nm)) were observed under the lower water tables and at the higher peat temperature. Our results provide an indication of the potential impacts of climatic change and anthropogenic drainage on the carbon cycle and/or water storage in a peatland and simultaneously imply the likelihood of potential damage to downstream ecosystems. Furthermore, our results highlight the need for local protection and sustainable development, as well as suggest that more research is required to better understand the impacts of climatic change and artificial disturbances on peatland degradation.

  7. Rapid response of hydrological loss of DOC to water table drawdown and warming in Zoige peatland: results from a mesocosm experiment.

    Directory of Open Access Journals (Sweden)

    Xue-Dong Lou

    Full Text Available A large portion of the global carbon pool is stored in peatlands, which are sensitive to a changing environment conditions. The hydrological loss of dissolved organic carbon (DOC is believed to play a key role in determining the carbon balance in peatlands. Zoige peatland, the largest peat store in China, is experiencing climatic warming and drying as well as experiencing severe artificial drainage. Using a fully crossed factorial design, we experimentally manipulated temperature and controlled the water tables in large mesocosms containing intact peat monoliths. Specifically, we determined the impact of warming and water table position on the hydrological loss of DOC, the exported amounts, concentrations and qualities of DOC, and the discharge volume in Zoige peatland. Our results revealed that of the water table position had a greater impact on DOC export than the warming treatment, which showed no interactive effects with the water table treatment. Both DOC concentration and discharge volume were significantly increased when water table drawdown, while only the DOC concentration was significantly promoted by warming treatment. Annual DOC export was increased by 69% and 102% when the water table, controlled at 0 cm, was experimentally lowered by -10 cm and -20 cm. Increases in colored and aromatic constituents of DOC (measured by Abs(254 nm, SUVA(254 nm, Abs(400 nm, and SUVA(400 nm were observed under the lower water tables and at the higher peat temperature. Our results provide an indication of the potential impacts of climatic change and anthropogenic drainage on the carbon cycle and/or water storage in a peatland and simultaneously imply the likelihood of potential damage to downstream ecosystems. Furthermore, our results highlight the need for local protection and sustainable development, as well as suggest that more research is required to better understand the impacts of climatic change and artificial disturbances on peatland degradation.

  8. Water laws in eleven midwestern states: summary tables

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, T.L.; Torpy, M.F.

    1979-06-01

    Basic information about the water laws of Arkansas, Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Ohio, and West Virginia is summarized. References to state laws and court decisions that may be useful in assessing the legal availability of water for energy development are provided. (MCW)

  9. Energy balance concept in the evaluation of water table management effects on corn growth: experimental investigation

    International Nuclear Information System (INIS)

    Kalita, P.K.; Kanwar, R.S.

    1992-01-01

    The effects of water table management practices (WTMP) on corn growth in 1989 and 1990 at two field sites, Ames and Ankeny, Iowa, were evaluated by calculating crop water stress index (CWSI) and monitoring plant physiological parameters during the growing seasons. Experiments were conducted on field lysimeters at the Ames site by maintaining water tables at 0.3-, 0.6-, and 0.9-m depths and in a subirrigation field at the Ankeny site with 0.2-, 0.3-, 0.6-, 0.9-, and 1.1-m water table depths, and periodically measuring leaf and air temperature, transpiration rate, stomatal conductance, and photosynthetically active radiation (PAR) using leaf chamber techniques. Net radiation of canopy was estimated using the leaf energy balance equation and leaf chamber measurements and then correlated with PAR. Analysis of data revealed that net radiation, leaf air temperature differential, transpiration rate, stomatal conductance, and CWSI were strongly related to WTMP during vegetative and flowering stages of corn growth. Excess water in the root zone with a water table depth of 0.2 m caused the maximum crop water stress and ceased crop growth. Both water and oxygen could be adequately maintained for favorable crop growth by adopting the best WTMP. Results indicate that plant physiological parameters and CWSI could be used to evaluate the effectiveness of WTMP and develop the best WTMP for corn growth in the humid region

  10. Model evaluation of seepage from uranium tailings disposal above and below the water table

    International Nuclear Information System (INIS)

    Nelson, R.W.; Meyer, P.R.; Oberlander, P.L.; Sneider, S.C.; Mayer, D.W.; Reisenauer, A.E.

    1983-03-01

    Model simulations identify the rate and amount of leachate released to the environment if disposed uranium mill tailings come into contact with ground water or if seepage from tailings reaches ground water. In this study, simulations of disposal above and below the water table, with various methods of leachate control, were compared. Three leachate control methods were used in the comparisons: clay bottom liners; stub-sidewall clay liners; and tailings drains with sumps, with the effluent pumped back from the sumps. The best leachate control for both above and below the water table is a combination of the three methods. The combined methods intercept up to 80% of the leachate volume in pits above the water table and intercept essentially all of the leachate in pits below the water table. Effluent pumping, however, requires continuous energy costs and an alternative method of disposal for the leachate that cannot be reused as makeup water in the mill process. Without the drains or effluent pumping, the clay bottom liners have little advantage in terms of the total volume of leachate lost. The clay liners do reduce the rate of leachate flow to the ground water, but the flow continues for a longer time. The buffering, sorption, and chemical reactions of the leachate passing directly through the liner are also advantages of the liner

  11. Preliminary Water-Table Map and Water-Quality Data for Part of the Matanuska-Susitna Valley, Alaska, 2005

    Science.gov (United States)

    Moran, Edward H.; Solin, Gary L.

    2006-01-01

    The Matanuska-Susitna Valley is in the northeastern part of the Cook Inlet Basin, Alaska, an area experiencing rapid population growth and development proximal to many lakes. Here water commonly flows between lakes and ground water, indicating interrelation between water quantity and quality. Thus concerns exist that poorer quality ground water may degrade local lake ecosystems. This concern has led to water-quality sampling in cooperation with the Alaska Department of Environmental Conservation and the Matanuska-Susitna Borough. A map showing the estimated altitude of the water table illustrates potential ground-water flow directions and areas where ground- and surface-water exchanges and interactions might occur. Water quality measured in selected wells and lakes indicates some differences between ground water and surface water. 'The temporal and spatial scarcity of ground-water-level and water-quality data limits the analysis of flow direction and water quality. Regionally, the water-table map indicates that ground water in the eastern and southern parts of the study area flows southerly. In the northcentral area, ground water flows predominately westerly then southerly. Although ground and surface water in most areas of the Matanuska-Susitna Valley are interconnected, they are chemically different. Analyses of the few water-quality samples collected in the area indicate that dissolved nitrite plus nitrate and orthophosphorus concentrations are higher in ground water than in surface water.'

  12. Combined uses of water-table fluctuation (WTF), chloride mass ...

    African Journals Online (AJOL)

    Agadaga

    isotopes methods to investigate groundwater recharge ... and isotopic characterization of groundwater, rainfall and the unsaturated zone were also carried out using a ..... Chloride concentrations in soil water extracted by lixiviation from.

  13. Environmental isotope profiles and evaporation in shallow water table soils

    International Nuclear Information System (INIS)

    Hussein, M.F.; Froehlich, K.; Nada, A.

    2001-01-01

    Environmental isotope methods have been employed to evaluate the processes of evaporation and soil salinisation in the Nile Delta. Stable isotope profiles (δ 18 O and δ 2 H) from three sites were analysed using a published isothermal model that analyses the steady-state isotopic profile in the unsaturated zone and provides an estimate of the evaporation rate. Evaporation rates estimated by this method at the three sites range between 60 and 98 mm y -1 which translates to an estimate of net water loss of one billion cubic meters per year from fallow soils on the Nile delta. Capillary rise of water through the root zone during the crop growing season is estimated to be three times greater than evaporation rate estimate and a modified water management strategy could be adopted in order to optimize water use and its management on the regional scale. (author)

  14. Radar sounding of bedrock and water table at Chalk River

    International Nuclear Information System (INIS)

    Annan, A.P.; Davis, J.L.

    1979-01-01

    When a spill of radioactive waste occurs, one of the main concerns is the flow pattern of ground water in the area of the spill. Ground probing radar is a relatively new geophysical technique which can provide high resolution data on the surficial geology and water distribution. The results of some preliminary radar experiments conducted at Chalk River Nuclear Laboratories (CRNL) of the Atomic Energy of Canada Limited (AECL), Chalk River, Ontario are presented. (auth)

  15. Water relations and foliar isotopic composition of Prosopis tamarugo Phil. an endemic tree of the Atacama Desert growing under three levels of water table depth.

    Directory of Open Access Journals (Sweden)

    Marco eGarrido

    2016-03-01

    Full Text Available Prosopis tamarugo Phil. is a strict phreatophyte tree species endemic to the Pampa del Tamarugal, Atacama Desert. The extraction of water for various uses has increased the depth of the water table in the Pampa aquifers threatening its conservation. This study aimed to determine the effect of the groundwater table depth on the water relations of P. tamarugo and to present thresholds of groundwater depth (GWD that can be used in the groundwater management of the P. tamarugo ecosystem. Three levels of GWD, 11.2 ± 0.3 m, 10.3 ± 0.3 m and 7.1 ± 0.1 m, (the last GWD being our reference were selected and groups of 4 individuals per GWD were studied in the months of January and July of the years 2011 through 2014. When the water table depth exceeded 10 m, P. tamarugo had lower pre-dawn and midday water potential but no differences were observed in minimum leaf stomatal resistance when compared to the condition of 7.1 m GWD; the leaf tissue increased its δ13C and δ18O composition. Furthermore, a smaller green canopy fraction of the trees and increased foliage loss in winter with increasing water table depth was observed. The differences observed in the physiological behavior of P. tamarugo trees, attributable to the ground water depth; show that increasing the depth of the water table from 7 to 11 m significantly affects the water status of P. tamarugo. The results indicate that P. tamarugo has an anisohydric stomatal behaviour and that given a reduction in water supply it regulates the water demand via foliage loss. The growth and leaf physiological activities are highly sensitive to GWD. The foliage loss appears to prevent the trees from reaching water potentials leading to complete loss of hydraulic functionality by cavitation. The balance achieved between water supply and demand was reflected in the low variation of the water potential and of the variables related to gas exchange over time for a given GWD. This acclimation capacity of P

  16. Water Relations and Foliar Isotopic Composition of Prosopis tamarugo Phil., an Endemic Tree of the Atacama Desert Growing at Three Levels of Water Table Depth.

    Science.gov (United States)

    Garrido, Marco; Silva, Paola; Acevedo, Edmundo

    2016-01-01

    Prosopis tamarugo Phil. is a strict phreatophyte tree species endemic to the "Pampa del Tamarugal", Atacama Desert. The extraction of water for various uses has increased the depth of the water table in the Pampa aquifers threatening its conservation. This study aimed to determine the effect of the groundwater table depth on the water relations of P. tamarugo and to present thresholds of groundwater depth (GWD) that can be used in the groundwater management of the P. tamarugo ecosystem. Three levels of GWD, 11.2 ± 0.3 m, 10.3 ± 0.3 m, and 7.1 ± 0.1 m, (the last GWD being our reference) were selected and groups of four individuals per GWD were studied in the months of January and July of the years 2011 through 2014. When the water table depth exceeded 10 m, P. tamarugo had lower pre-dawn and mid-day water potential but no differences were observed in minimum leaf stomatal resistance when compared to the condition of 7.1 m GWD; the leaf tissue increased its δ(13)C and δ(18)O composition. Furthermore, a smaller green canopy fraction of the trees and increased foliage loss in winter with increasing water table depth was observed. The differences observed in the physiological behavior of P. tamarugo trees, attributable to the ground water depth; show that increasing the depth of the water table from 7 to 11 m significantly affects the water status of P. tamarugo. The results indicate that P. tamarugo has an anisohydric stomatal behavior and that given a reduction in water supply it regulates the water demand via foliage loss. The growth and leaf physiological activities are highly sensitive to GWD. The foliage loss appears to prevent the trees from reaching water potentials leading to complete loss of hydraulic functionality by cavitation. The balance achieved between water supply and demand was reflected in the low variation of the water potential and of the variables related to gas exchange over time for a given GWD. This acclimation capacity of P. tamarugo after

  17. Suppression device for the reactor water level lowering

    International Nuclear Information System (INIS)

    Kasuga, Hajime; Kasuga, Hiroshi.

    1984-01-01

    Purpose: To suppress the lowering in the reactor water level so as to avoid unnecessary actuation of ECCS upon generation of transient changes which forecasts the lowering of the reactor water level in a BWR type reactor. Constitution: There are provided a water level suppression signal generator for generating a water level suppression signal upon generation of a transient change signal which forecasts the water level lowering in a nuclear reactor and a recycling flow rate controller that applies a recycling flow rate control signal to a recycling pump drive motor by the water level lowering suppression signal. The velocity of the recycling pump is controlled by a reactor scram signal by way of the water level lowering suppresion signal generator and a recycling flow rate controller. Then, the recycling reactor core flow rate is decreased and the void amount in the reactor is transiently increased where the water level tends to increase. Accordingly, the water level lowering by the scram is moderated by the increasing tendency of the water level. (Ikeda, J.)

  18. Effect of vegetation removal and water table drawdown on the non-methane biogenic volatile organic compound emissions in boreal peatland microcosms

    Science.gov (United States)

    Faubert, Patrick; Tiiva, Päivi; Rinnan, Åsmund; Räty, Sanna; Holopainen, Jarmo K.; Holopainen, Toini; Rinnan, Riikka

    2010-11-01

    Biogenic volatile organic compound (BVOC) emissions are important in the global atmospheric chemistry and their feedbacks to global warming are uncertain. Global warming is expected to trigger vegetation changes and water table drawdown in boreal peatlands, such changes have only been investigated on isoprene emission but never on other BVOCs. We aimed at distinguishing the BVOCs released from vascular plants, mosses and peat in hummocks (dry microsites) and hollows (wet microsites) of boreal peatland microcosms maintained in growth chambers. We also assessed the effect of water table drawdown (-20 cm) on the BVOC emissions in hollow microcosms. BVOC emissions were measured from peat samples underneath the moss surface after the 7-week-long experiment to investigate whether the potential effects of vegetation and water table drawdown were shown. BVOCs were sampled using a conventional chamber method, collected on adsorbent and analyzed with GC-MS. In hummock microcosms, vascular plants increased the monoterpene emissions compared with the treatment where all above-ground vegetation was removed while no effect was detected on the sesquiterpenes, other reactive VOCs (ORVOCs) and other VOCs. Peat layer from underneath the surface with intact vegetation had the highest sesquiterpene emissions. In hollow microcosms, intact vegetation had the highest sesquiterpene emissions. Water table drawdown decreased monoterpene and other VOC emissions. Specific compounds could be closely associated to the natural/lowered water tables. Peat layer from underneath the surface of hollows with intact vegetation had the highest emissions of monoterpenes, sesquiterpenes and ORVOCs whereas water table drawdown decreased those emissions. The results suggest that global warming would change the BVOC emission mixtures from boreal peatlands following changes in vegetation composition and water table drawdown.

  19. Water table in Long Island, New York, March 1971

    Science.gov (United States)

    Koszalka, Edward J.; Koch, Ellis

    1971-01-01

    The geologic framework and the hydrologic situation in Long Island are periodically reviewed by the U.S. Geological Survey as new knowledge is obtained from current investigations. This work is done through cooperative programs with Nassau and Suffolk County agencies and the New York State Department of Environmental Conservation. A unique opportunity to update many of the hydrogeologic maps occurred when the Geological Survey's Mineola, N.Y., office participated in the New England River Basins Commission's "Long Island Sound Study." This map, one of a series of open-file maps showing the updated information, was compiled from data obtained from G. E. Kimmel (written commun., July 1972) and Jensen and Soren (in press). Comparison of the March 1971 data with similar data for March 1970 (Kimmel, 1970) shows virtually no change in water levels on Long Island during the 12 month period, except for a slight decline in levels in central Suffolk County.

  20. Methane transport and emissions from soil as affected by water table and vascular plants.

    Science.gov (United States)

    Bhullar, Gurbir S; Iravani, Majid; Edwards, Peter J; Olde Venterink, Harry

    2013-09-08

    The important greenhouse gas (GHG) methane is produced naturally in anaerobic wetland soils. By affecting the production, oxidation and transport of methane to the atmosphere, plants have a major influence upon the quantities emitted by wetlands. Different species and functional plant groups have been shown to affect these processes differently, but our knowledge about how these effects are influenced by abiotic factors such as water regime and temperature remains limited. Here we present a mesocosm experiment comparing eight plant species for their effects on internal transport and overall emissions of methane under contrasting hydrological conditions. To quantify how much methane was transported internally through plants (the chimney effect), we blocked diffusion from the soil surface with an agar seal. We found that graminoids caused higher methane emissions than forbs, although the emissions from mesocosms with different species were either lower than or comparable to those from control mesocosms with no plant (i.e. bare soil). Species with a relatively greater root volume and a larger biomass exhibited a larger chimney effect, though overall methane emissions were negatively related to plant biomass. Emissions were also reduced by lowering the water table. We conclude that plant species (and functional groups) vary in the degree to which they transport methane to the atmosphere. However, a plant with a high capacity to transport methane does not necessarily emit more methane, as it may also cause more rhizosphere oxidation of methane. A shift in plant species composition from graminoids to forbs and/or from low to high productive species may lead to reduction of methane emissions.

  1. Agricultural water conservation programs in the lower Colorado River Authority

    International Nuclear Information System (INIS)

    Kabir, J.

    1993-01-01

    Rice irrigation is the largest user of water within the area served by the Lower Colorado River Authority (LCRA), accounting for approximately 75 percent of total annual surface and ground water demands. In an average year, about 30 percent of surface water supplied to rice irrigation is satisfied with water released from the storage in the Highland Lakes located at the upstream reaches of the Lower Colorado River and its tributaries. During a severe drought, the demand for stored water could be as much as 70 percent of annual rice irrigation demand. LCRA owns and operates two irrigation canal systems which together supply water to irrigate 60,000 acres of rice each year. These irrigation systems are the Lakeside and Gulf Coast Irrigation Divisions. The Lakeside system is located in Colorado and Wharton Counties and the Gulf Coast system is located in Wharton and Matagorda Counties. In the 1987 and 1989, the Lower Colorado River Authority Board of Directors authorized implementation and funding for Canal Rehabilitation Project and Irrigation Water Measurement Project respectively. These two projects are key initiatives to agricultural water conservation goals established in the LCRA Water Management Plan and Water Conservation Policy. In addition LCRA participated actively in agricultural water conservation research projects and technology transfer activities

  2. Measurement of the 226Ra-concentration in bottled Austrian mineral waters and table beverages

    International Nuclear Information System (INIS)

    Friedmann, H.; Hernegger, F.

    1978-01-01

    226 Ra being regarded nowadays as a toxic trace element, a systementic examination of bottled Austrian mineral waters and table beverages has been carried out. Only in one case was the maximum allowable concentration of 3.3 pCi/l, a value set up by the WHO, clearly exceeded. (orig.) [de

  3. Accuracy of spatio-temporal RARX model predictions of water table depths

    NARCIS (Netherlands)

    Knotters, M.; Bierkens, M.F.P.

    2002-01-01

    Time series of water table depths (Ht) are predicted in space using a regionalised autoregressive exogenous variable (RARX) model with precipitation surplus (Pt) as input variable. Because of their physical basis, RARX model parameters can be guessed from auxiliary information such as a digital

  4. Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

    Science.gov (United States)

    Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

    2014-03-01

    Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Regional water table (2016) in the Mojave River and Morongo groundwater basins, southwestern Mojave Desert, California

    Science.gov (United States)

    Dick, Meghan; Kjos, Adam

    2017-12-07

    From January to April 2016, the U.S. Geological Survey (USGS), the Mojave Water Agency, and other local water districts made approximately 1,200 water-level measurements in about 645 wells located within 15 separate groundwater basins, collectively referred to as the Mojave River and Morongo groundwater basins. These data document recent conditions and, when compared with older data, changes in groundwater levels. A water-level contour map was drawn using data measured in 2016 that shows the elevation of the water table and general direction of groundwater movement for most of the groundwater basins. Historical water-level data stored in the USGS National Water Information System (https://waterdata.usgs.gov/nwis/) database were used in conjunction with data collected for this study to construct 37 hydrographs to show long-term (1930–2016) and short-term (1990–2016) water-level changes in the study area.

  6. Sensitivity of stream flow and water table depth to potential climatic variability in a coastal forested watershed

    Science.gov (United States)

    Zhaohua Dai; Carl Trettin; Changsheng Li; Devendra M. Amatya; Ge Sun; Harbin Li

    2010-01-01

    A physically based distributed hydrological model, MIKE SHE, was used to evaluate the effects of altered temperature and precipitation regimes on the streamflow and water table in a forested watershed on the southeastern Atlantic coastal plain. The model calibration and validation against both streamflow and water table depth showed that the MIKE SHE was applicable for...

  7. Controlled laboratory experiments and modeling of vegetative filter strips with shallow water tables

    Science.gov (United States)

    Fox, Garey A.; Muñoz-Carpena, Rafael; Purvis, Rebecca A.

    2018-01-01

    Natural or planted vegetation at the edge of fields or adjacent to streams, also known as vegetative filter strips (VFS), are commonly used as an environmental mitigation practice for runoff pollution and agrochemical spray drift. The VFS position in lowlands near water bodies often implies the presence of a seasonal shallow water table (WT). In spite of its potential importance, there is limited experimental work that systematically studies the effect of shallow WTs on VFS efficacy. Previous research recently coupled a new physically based algorithm describing infiltration into soils bounded by a water table into the VFS numerical overland flow and transport model, VFSMOD, to simulate VFS dynamics under shallow WT conditions. In this study, we tested the performance of the model against laboratory mesoscale data under controlled conditions. A laboratory soil box (1.0 m wide, 2.0 m long, and 0.7 m deep) was used to simulate a VFS and quantify the influence of shallow WTs on runoff. Experiments included planted Bermuda grass on repacked silt loam and sandy loam soils. A series of experiments were performed including a free drainage case (no WT) and a static shallow water table (0.3-0.4 m below ground surface). For each soil type, this research first calibrated VFSMOD to the observed outflow hydrograph for the free drainage experiments to parameterize the soil hydraulic and vegetation parameters, and then evaluated the model based on outflow hydrographs for the shallow WT experiments. This research used several statistical metrics and a new approach based on hypothesis testing of the Nash-Sutcliffe model efficiency coefficient (NSE) to evaluate model performance. The new VFSMOD routines successfully simulated the outflow hydrographs under both free drainage and shallow WT conditions. Statistical metrics considered the model performance valid with greater than 99.5% probability across all scenarios. This research also simulated the shallow water table experiments with

  8. Simulation of upward flux from shallow water-table using UPFLOW model

    Directory of Open Access Journals (Sweden)

    M. H. Ali

    2013-11-01

    Full Text Available The upward movement of water by capillary rise from shallow water-table to the root zone is an important incoming flux. For determining exact amount of irrigation requirement, estimation of capillary flux or upward flux is essential. Simulation model can provide a reliable estimate of upward flux under variable soil and climatic conditions. In this study, the performance of model UPFLOW to estimate upward flux was evaluated. Evaluation of model performance was performed with both graphical display and statistical criteria. In distribution of simulated capillary rise values against observed field data, maximum data points lie around the 1:1 line, which means that the model output is reliable and reasonable. The coefficient of determination between observed and simulated values was 0.806 (r = 0.93, which indicates a good inter-relation between observed and simulated values. The relative error, model efficiency, and index of agreement were found as 27.91%, 85.93% and 0.96, respectively. Considering the graphical display of observed and simulated upward flux and statistical indicators, it can be concluded that the overall performance of the UPFLOW model in simulating actual upward flux from a crop field under variable water-table condition is satisfactory. Thus, the model can be used to estimate capillary rise from shallow water-table for proper estimation of irrigation requirement, which would save valuable water from over-irrigation.

  9. The effect of urbanization in an arid region: Formation of a perched water table that causes environmental damages

    Science.gov (United States)

    Karnieli, A.; Issar, A.; Wolf, M.

    1984-03-01

    Construction in a new neighborhood in the israeli town of Dimona, situated in an arid region in the south of the country (150 mm average annual rainfall), resulted in a rise in groundwater levels during the subsequent rainy seasons This caused flooding of shelter basements, soil sliding, and sagging which permanently damaged walls and buildings The neighborhood had been built on continental sands and marls blanketed by loess, on a valley slope near a rocky anticlinal dip-slope Subsurface studies, using piezometer holes and groundwater analyses, revealed the presence of sand lenses alternating with plastic marls, which act as seasonal aquifers with perched water tables Groundwaters obtain high SO{4/-2} and Cl- corrosivity through contact with these nonflushed marls of the Neogene valley fill (Hazeva Formation) The reasons for the rising of groundwater were found to be (a) artificial interference with the natural (pre-construction) drainage system—interception of the hillside runoff by building plots, roads, etc, (b) partial denudation of the loess blanket, increasing the local infiltration and the build-up of local, perched water tables, and (c) corrosion of concrete and steel pipelines, as well as foundations, by prolonged contact with corrosive groundwater, resulting in haphazard but massive leakage Guidelines are proposed for an environmental improvement plan, which would include terracing and planting of the watershed above town to increase evapotranspiration, lowering of the water table by pumping, and diverting the water to suburban parks (groves of saltresistant trees), and replacement of steel and cement pipes by a non-corrodable plastic pipe system

  10. Increasing the utility of regional water table maps: a new method for estimating groundwater recharge

    Science.gov (United States)

    Gilmore, T. E.; Zlotnik, V. A.; Johnson, M.

    2017-12-01

    Groundwater table elevations are one of the most fundamental measurements used to characterize unconfined aquifers, groundwater flow patterns, and aquifer sustainability over time. In this study, we developed an analytical model that relies on analysis of groundwater elevation contour (equipotential) shape, aquifer transmissivity, and streambed gradient between two parallel, perennial streams. Using two existing regional water table maps, created at different times using different methods, our analysis of groundwater elevation contours, transmissivity and streambed gradient produced groundwater recharge rates (42-218 mm yr-1) that were consistent with previous independent recharge estimates from different methods. The three regions we investigated overly the High Plains Aquifer in Nebraska and included some areas where groundwater is used for irrigation. The three regions ranged from 1,500 to 3,300 km2, with either Sand Hills surficial geology, or Sand Hills transitioning to loess. Based on our results, the approach may be used to increase the value of existing water table maps, and may be useful as a diagnostic tool to evaluate the quality of groundwater table maps, identify areas in need of detailed aquifer characterization and expansion of groundwater monitoring networks, and/or as a first approximation before investing in more complex approaches to groundwater recharge estimation.

  11. Lower limb joint moment during walking in water.

    Science.gov (United States)

    Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami

    2003-11-04

    Walking in water is a widely used rehabilitation method for patients with orthopedic disorders or arthritis, based on the belief that the reduction of weight in water makes it a safer medium and prevents secondary injuries of the lower-limb joints. To our knowledge, however, no experimental data on lower-limb joint moment during walking in water is available. The aim of this study was to quantify the joint moments of the ankle, knee, and hip during walking in water in comparison with those on land. Eight healthy volunteers walked on land and in water at a speed comfortable for them. A video-motion analysis system and waterproof force platform were used to obtain kinematic data and to calculate the joint moments. The hip joint moment was shown to be an extension moment almost throughout the stance phase during walking in water, while it changed from an extension- to flexion-direction during walking on land. The knee joint moment had two extension peaks during walking on land, whereas it had only one extension peak, a late one, during walking in water. The ankle joint moment during walking in water was considerably reduced but in the same direction, plantarflexion, as that during walking on land. The joint moments of the hip, knee, and ankle were not merely reduced during walking in water; rather, inter-joint coordination was totally changed.

  12. Simulation of the water-table altitude in the Biscayne Aquifer, southern Dade County, Florida, water years 1945-89

    Science.gov (United States)

    Merritt, M.L.

    1995-01-01

    A digital model of the flow system in the highly permeable surficial aquifer of southern Dade County, Florida, was constructed for the purposes of better understanding processes that influence the flow system and of supporting the construction of a subregional model of the transport of brackish water from a flowing artesian well. Problems that needed resolution in this endeavor included the development of methods to represent the influence of flowing surface water in seasonally inundated wetlands and the influence of a network of controlled canals developed in stages during the simulation time period (water years 1945-89). An additional problem was the general lack of natural aquifer boundaries near the boundaries of the study area. The model construction was based on a conceptual description of the Biscayne aquifer developed from the results of previous U.S. Geological Survey investigations. Modifications were made to an existing three- dimensional finite-difference simulator of ground- water flow to enable an upper layer of the grid to represent seasonally occurring overland sheetflow in a series of transient simulations of water levels from 1945 to 1989. A rewetting procedure was developed for the simulator that permitted resaturation of cells in this layer when the wet season recurred. An "equivalent hydraulic conductivity" coefficient was assigned to the overland flow layer that was analogous, subject to various approximations, to the use of the Manning equation. The surficial semiconfining peat and marl layers, levees, canals, and control structures were also represented as part of the model grid with the appropriate choices of hydraulic coefficient values. For most of the Biscayne aquifer grid cells, the value assigned to hydraulic conductivity for model calibration was 30,000 feet per day and the value assigned to porosity was 20 percent. Boundary conditions were specified near data sites having long-term records of surface-water stages or water-table

  13. Water loss in table grapes: model development and validation under dynamic storage conditions

    Directory of Open Access Journals (Sweden)

    Ericsem PEREIRA

    2017-09-01

    Full Text Available Abstract Water loss is a critical problem affecting the quality of table grapes. Temperature and relative humidity (RH are essential in this process. Although mathematical modelling can be applied to measure constant temperature and RH impacts, it is proved that variations in storage conditions are normally encountered in the cold chain. This study proposed a methodology to develop a weight loss model for table grapes and validate its predictions in non-constant conditions of a domestic refrigerator. Grapes were maintained under controlled conditions and the weight loss was measured to calibrate the model. The model described the water loss process adequately and the validation tests confirmed its predictive ability. Delayed cooling tests showed that estimated transpiration rates in subsequent continuous temperature treatment was not significantly influenced by prior exposure conditions, suggesting that this model may be useful to estimate the weight loss consequences of interruptions in the cold chain.

  14. Simulating streamflow and water table depth with a coupled hydrological model

    Directory of Open Access Journals (Sweden)

    Alphonce Chenjerayi Guzha

    2010-09-01

    Full Text Available A coupled model integrating MODFLOW and TOPNET with the models interacting through the exchange of recharge and baseflow and river-aquifer interactions was developed and applied to the Big Darby Watershed in Ohio, USA. Calibration and validation results show that there is generally good agreement between measured streamflow and simulated results from the coupled model. At two gauging stations, average goodness of fit (R2, percent bias (PB, and Nash Sutcliffe efficiency (ENS values of 0.83, 11.15%, and 0.83, respectively, were obtained for simulation of streamflow during calibration, and values of 0.84, 8.75%, and 0.85, respectively, were obtained for validation. The simulated water table depths yielded average R2 values of 0.77 and 0.76 for calibration and validation, respectively. The good match between measured and simulated streamflows and water table depths demonstrates that the model is capable of adequately simulating streamflows and water table depths in the watershed and also capturing the influence of spatial and temporal variation in recharge.

  15. Tempered Water Lower Port Connector Structural Analysis Verification

    International Nuclear Information System (INIS)

    CREA, B.A.

    2000-01-01

    Structural analysis of the lower port connection of the Tempered Water System of the Cold Vacuum Drying Facility was performed. Subsequent detailed design changes to enhance operability resulted in the need to re-evaluate the bases of the original analysis to verify its continued validity. This evaluation is contained in Appendix A of this report. The original evaluation is contained in Appendix B

  16. Hanford site water table changes 1950-1980: data observations and evaluation

    International Nuclear Information System (INIS)

    Zimmerman, D.A.; Reisenauer, A.E.; Black, G.D.; Young, M.A.

    1986-04-01

    The basalt formations underlying the Hanford site are being considered for characterization and evaluation as a deep geologic repository for defense and commercial radioactive wastes. To understand the hydrology of the Hanford area, we need to know if the ground-water system is in steady state and what impact a change in surface stress from artificial recharge may have on the underlying basalt aquifers. Researchers at Pacific Northwest Laboratory are supporting efforts to understand these issues by illustrating how changes in wastewater disposal activities at the Hanford site have altered the configuration of the water table surface with time. The objective of this work was to determine the magnitude and direction of changes in the elevation of the water table across the Hanford site from 1950 to 1980. Plots of the magnitudes of water-level changes occurring over 5-year intervals from 1950 through 1980 are presented. The water-level changes that occurred during each 5-year interval are related to water discharges from nuclear fuel reprocessing facilities or other discharge sources. The plots of water-level changes show large water-level increases in the vicinity of the Separations Area (200 East and 200 West) from 1950 to 1960; the rate of increase of water-level changes grows more slowly from 1960 to 1970, while the areal extent of the mounding continues to expand. Only small changes occur from 1970 to 1980; during this time period, the unconfined system appears to be in approximate equilibrium with the sources. Based on previous experience, it is believed that an increase in ground-water mounding will begin to appear near the 200 East Area B Pond as a result of the increased discharges from the restart of PUREX in 1983

  17. Quality of surface waters in the lower Columbia River Basin

    Science.gov (United States)

    Santos, John F.

    1965-01-01

    This report, made during 1959-60, provides reconnaissance data on the quality of waters in the lower Columbia River basin ; information on present and future water problems in the basin; and data that can be employed both in water-use studies and in planning future industrial, municipal, and agricultural expansion within this area. The lower Columbia River basin consists of approximately 46,000 square miles downstream from the confluence of the Snake and Columbia Rivers The region can be divided into three geographic areas. The first is the heavily forested, sparsely populated mountain regions in which quality of water in general is related to geologic and climatological factors. The second is a semiarid plateau east of the Cascade Mountains; there differences in geology and precipitation, together with more intensive use of available water for irrigation, bring about marked differences in water quality. The third is the Willamette-Puget trough area in which are concentrated most of the industry and population and in which water quality is influenced by sewage and industrial waste disposal. The majority of the streams in the lower Columbia River basin are calcium magnesium bicarbonate waters. In general, the rivers rising in the. Coast Range and on the west slope of the Cascade Range contain less than 100 parts per million of dissolved solids, and hardness of the water is less than 50 parts per million. Headwater reaches of the streams on the east slope of the Cascade Range are similar to those on the west slope; but, downstream, irrigation return flows cause the dissolved-solids content and hardness to increase. Most of the waters, however, remain calcium magnesium bicarbonate in type. The highest observed dissolved-solids concentrations and also some changes in chemical composition occur in the streams draining the more arid parts of the area. In these parts, irrigation is chiefly responsible for increasing the dissolved-solids concentration and altering the

  18. "Periodic-table-style" paper device for monitoring heavy metals in water.

    Science.gov (United States)

    Li, Miaosi; Cao, Rong; Nilghaz, Azadeh; Guan, Liyun; Zhang, Xiwang; Shen, Wei

    2015-03-03

    If a paper-based analytical device (μ-PAD) could be made by printing indicators for detection of heavy metals in chemical symbols of the metals in a style of the periodic table of elements, it could be possible for such μ-PAD to report the presence and the safety level of heavy metal ions in water simultaneously and by text message. This device would be able to provide easy solutions to field-based monitoring of heavy metals in industrial wastewater discharges and in irrigating and drinking water. Text-reporting could promptly inform even nonprofessional users of the water quality. This work presents a proof of concept study of this idea. Cu(II), Ni(II), and Cr(VI) were chosen to demonstrate the feasibility, specificity, and reliability of paper-based text-reporting devices for monitoring heavy metals in water.

  19. Effects of Permanently Raised Water Tables on Forest Overstory Vegetation in the Vicinity of the Tennessee-Tombigbee Waterway.

    Science.gov (United States)

    1982-08-01

    Mississippi Valley* Common Name Scientific Name Very Tolerant** Water hickory Carya aquatica Pecan C. illinoensis Buttonbush Cephalanthus occidentalis...Table I (Concluded) Common Name Scientific Name Intolerant* Ironwood Carpinus caroliniana Bitternut hickory Carya cordiformis Shellbark

  20. Lower Charles River Bathymetry: 108 Years of Fresh Water

    Science.gov (United States)

    Yoder, M.; Sacarny, M.

    2017-12-01

    The Lower Charles River is a heavily utilized urban river that runs between Cambridge and Boston in Massachusetts. The recreational usage of the river is dependent on adequate water depths, but there have been no definitive prior studies on the sedimentation rate of the Lower Charles River. The river transitioned from tidal to a freshwater basin in 1908 due to the construction of the (old) Charles River Dam. Water surface height on the Lower Charles River is maintained within ±1 foot through controlled discharge at the new Charles River Dam. The current study area for historical comparisons is from the old Charles River Dam to the Boston University Bridge. This study conducted a bathymetric survey of the Lower Charles River, digitized three prior surveys in the study area, calculated volumes and depth distributions for each survey, and estimated sedimentation rates from fits to the volumes over time. The oldest chart digitized was produced in 1902 during dam construction deliberations. The average sedimentation rate is estimated as 5-10 mm/year, which implies 1.8-3.5 feet sedimentation since 1908. Sedimentation rates and distributions are necessary to develop comprehensive management plans for the river and there is evidence to suggest that sedimentation rates in the shallow upstream areas are higher than the inferred rates in the study area.

  1. High-Resolution Assimilation of GRACE Terrestrial Water Storage Observations to Represent Local-Scale Water Table Depths

    Science.gov (United States)

    Stampoulis, D.; Reager, J. T., II; David, C. H.; Famiglietti, J. S.; Andreadis, K.

    2017-12-01

    Despite the numerous advances in hydrologic modeling and improvements in Land Surface Models, an accurate representation of the water table depth (WTD) still does not exist. Data assimilation of observations of the joint NASA and DLR mission, Gravity Recovery and Climate Experiment (GRACE) leads to statistically significant improvements in the accuracy of hydrologic models, ultimately resulting in more reliable estimates of water storage. However, the usually shallow groundwater compartment of the models presents a problem with GRACE assimilation techniques, as these satellite observations account for much deeper aquifers. To improve the accuracy of groundwater estimates and allow the representation of the WTD at fine spatial scales we implemented a novel approach that enables a large-scale data integration system to assimilate GRACE data. This was achieved by augmenting the Variable Infiltration Capacity (VIC) hydrologic model, which is the core component of the Regional Hydrologic Extremes Assessment System (RHEAS), a high-resolution modeling framework developed at the Jet Propulsion Laboratory (JPL) for hydrologic modeling and data assimilation. The model has insufficient subsurface characterization and therefore, to reproduce groundwater variability not only in shallow depths but also in deep aquifers, as well as to allow GRACE assimilation, a fourth soil layer of varying depth ( 1000 meters) was added in VIC as the bottom layer. To initialize a water table in the model we used gridded global WTD data at 1 km resolution which were spatially aggregated to match the model's resolution. Simulations were then performed to test the augmented model's ability to capture seasonal and inter-annual trends of groundwater. The 4-layer version of VIC was run with and without assimilating GRACE Total Water Storage anomalies (TWSA) over the Central Valley in California. This is the first-ever assimilation of GRACE TWSA for the determination of realistic water table depths, at

  2. Environmental impact assessment of quarries under water table: state of the art

    International Nuclear Information System (INIS)

    Menatti, M.; Vismara, R.

    2009-01-01

    After an overview of environmental problems concerning pits under water table, data and results showed in a few examples of literature and in some Environmental Impact Study are summarized. A close examination about sector normative instruments, in the field of E.I.A. (Environmental Impact Assessment) and S.E.A. (Strategic Environmental Assessment) is showed, through some key elements obtained from a few guidelines expressed by control and authorization governmental authority.In addition, the paper deals with a specific problem about wash water management and, in particular, silt material management; the possible impacts derived from the directly wash water introduction in the pit lake and from the use of settling lagoon are analyzed. [it

  3. A study on the influence of tides on the water table conditions of the shallow coastal aquifers

    Science.gov (United States)

    Singaraja, C.; Chidambaram, S.; Jacob, Noble

    2018-03-01

    Tidal variation and water level in aquifer is an important function in the coastal environment, this study attempts to find the relationship between water table fluctuation and tides in the shallow coastal aquifers. The study was conducted by selecting three coastal sites and by monitoring the water level for every 2-h interval in 24 h of observation. The study was done during two periods of full moon and new moon along the Cuddalore coastal region of southern part of Tamil Nadu, India. The study shows the relationship between tidal variation, water table fluctuations, dissolved oxygen, and electrical conductivity. An attempt has also been made in this study to approximate the rate of flow of water. Anyhow, the differences are site specific and the angle of inclination of the water table shows a significant relation to the mean sea level, with respect to the distance of the point of observation from the sea and elevation above mean sea level.

  4. Secondary mineral evidence of large-scale water table fluctuations at Yucca Mountain, Nye County, Nevada

    International Nuclear Information System (INIS)

    Whelan, J.F.; Moscati, R.J.; Marshall, B.D

    1997-12-01

    At Yucca Mountain, currently under consideration as a potential permanent underground repository for high-level radioactive wastes, the present-day water table is 500 to 700 m deep. This thick unsaturated zone (UZ) is part of the natural barrier system and is regarded as a positive attribute of the potential site. The USGS has studied the stable isotopes and petrography of secondary calcite and silica minerals that coat open spaces in the UZ and form irregular veins and masses in the saturated zone (SZ). This paper reviews the findings from the several studies undertaken at Yucca Mountain on its mineralogy

  5. Seasonal variations of water vapor in the tropical lower statosphere

    Science.gov (United States)

    Mote, Philip W.; Rosenlof, Karen H.; Holton, James R.; Harwood, Robert S.; Waters, Joe W.

    1995-01-01

    Measurments of stratospheric water vapor by the Microwave Limb Sounder (MLS) aboard the Upper Atmosphere Research Satellite (UARS) show that in the tropical lower statosphere, low-frequency variations are closely related to the annual cycle in tropical tropopause temperatures. Tropical stratospheric air appears to retain information about the tropopause conditions it enconters for over a year as it rises through the stratosphere. A two-dimensional Lagrangian model is used to relate MLS measurements to the temperature that tropical air parcels encounter when crossing the 100 hPa surface.

  6. Effectiveness of table top water pitcher filters to remove arsenic from drinking water.

    Science.gov (United States)

    Barnaby, Roxanna; Liefeld, Amanda; Jackson, Brian P; Hampton, Thomas H; Stanton, Bruce A

    2017-10-01

    Arsenic contamination of drinking water is a serious threat to the health of hundreds of millions of people worldwide. In the United States ~3 million individuals drink well water that contains arsenic levels above the Environmental Protection Agency (EPA) maximum contaminant level (MCL) of 10μg/L. Several technologies are available to remove arsenic from well water including anion exchange, adsorptive media and reverse osmosis. In addition, bottled water is an alternative to drinking well water contaminated with arsenic. However, there are several drawbacks associated with these approaches including relatively high cost and, in the case of bottled water, the generation of plastic waste. In this study, we tested the ability of five tabletop water pitcher filters to remove arsenic from drinking water. We report that only one tabletop water pitcher filter tested, ZeroWater®, reduced the arsenic concentration, both As 3+ and As 5+ , from 1000μg/L to water and its use reduces plastic waste associated with bottled water. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Understanding and quantifying focused, indirect groundwater recharge from ephemeral streams using water table fluctuations

    Science.gov (United States)

    Cuthbert, M. O.; Acworth, R. I.; Andersen, M. S.; Larsen, J. R.; McCallum, A. M.; Rau, G. C.; Tellam, J. H.

    2016-02-01

    Understanding and managing groundwater resources in drylands is a challenging task, but one that is globally important. The dominant process for dryland groundwater recharge is thought to be as focused, indirect recharge from ephemeral stream losses. However, there is a global paucity of data for understanding and quantifying this process and transferable techniques for quantifying groundwater recharge in such contexts are lacking. Here we develop a generalized conceptual model for understanding water table and groundwater head fluctuations due to recharge from episodic events within ephemeral streams. By accounting for the recession characteristics of a groundwater hydrograph, we present a simple but powerful new water table fluctuation approach to quantify focused, indirect recharge over both long term and event time scales. The technique is demonstrated using a new, and globally unparalleled, set of groundwater observations from an ephemeral stream catchment located in NSW, Australia. We find that, following episodic streamflow events down a predominantly dry channel system, groundwater head fluctuations are controlled by pressure redistribution operating at three time scales from vertical flow (days to weeks), transverse flow perpendicular to the stream (weeks to months), and longitudinal flow parallel to the stream (years to decades). In relative terms, indirect recharge decreases almost linearly away from the mountain front, both in discrete monitored events as well as in the long-term average. In absolute terms, the estimated indirect recharge varies from 80 to 30 mm/a with the main uncertainty in these values stemming from uncertainty in the catchment-scale hydraulic properties.

  8. Peatland pines as a proxy for water table fluctuations: disentangling tree growth, hydrology and possible human influence.

    Science.gov (United States)

    Smiljanić, Marko; Seo, Jeong-Wook; Läänelaid, Alar; van der Maaten-Theunissen, Marieke; Stajić, Branko; Wilmking, Martin

    2014-12-01

    Dendrochronological investigations of Scots pine (Pinus sylvestris L.) growing on Männikjärve peatland in central Estonia showed that annual tree growth of peatland pines can be used as a proxy for past variations of water table levels. Reconstruction of past water table levels can help us to better understand the dynamics of various ecological processes in peatlands, e.g. the formation of vegetation patterns or carbon and nitrogen cycling. Männikjärve bog has one of the longest water table records in the boreal zone, continuously monitored since 1956. Common uncertainties encountered while working with peatland trees (e.g. narrow, missing and wedging rings) were in our case exacerbated with difficulties related to the instability of the relationship between tree growth and peatland environment. We hypothesized that the instable relationship was mainly due to a significant change of the limiting factor, i.e. the rise of the water table level due to human activity. To test our hypothesis we had to use several novel methods of tree-ring chronology analysis as well as to test explicitly whether undetected missing rings biased our results. Since the hypothesis that the instable relationship between tree growth and environment was caused by a change in limiting factor could not be rejected, we proceeded to find possible significant changes of past water table levels using structural analysis of the tree-ring chronologies. Our main conclusions were that peatland pines can be proxies to water table levels and that there were several shifting periods of high and low water table levels in the past 200 years. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil.

    Science.gov (United States)

    Silva, A C; Higuchi, P; van den Berg, E

    2010-08-01

    In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh), total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

  10. Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil

    Directory of Open Access Journals (Sweden)

    AC. Silva

    Full Text Available In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh, total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

  11. Climate change and water table fluctuation: Implications for raised bog surface variability

    Science.gov (United States)

    Taminskas, Julius; Linkevičienė, Rita; Šimanauskienė, Rasa; Jukna, Laurynas; Kibirkštis, Gintautas; Tamkevičiūtė, Marija

    2018-03-01

    Cyclic peatland surface variability is influenced by hydrological conditions that highly depend on climate and/or anthropogenic activities. A low water level leads to a decrease of peatland surface and an increase of C emissions into the atmosphere, whereas a high water level leads to an increase of peatland surface and carbon sequestration in peatlands. The main aim of this article is to evaluate the influence of hydrometeorological conditions toward the peatland surface and its feedback toward the water regime. A regional survey of the raised bog water table fluctuation and surface variability was made in one of the largest peatlands in Lithuania. Two appropriate indicators for different peatland surface variability periods (increase and decrease) were detected. The first one is an 200 mm y- 1 average net rainfall over a three-year range. The second one is an average annual water depth of 25-30 cm. The application of these indicators enabled the reconstruction of Čepkeliai peatland surface variability during a 100 year period. Processes of peatland surface variability differ in time and in separate parts of peatland. Therefore, internal subbasins in peatland are formed. Subbasins involve autogenic processes that can later affect their internal hydrology, nutrient status, and vegetation succession. Internal hydrological conditions, surface fluctuation, and vegetation succession in peatland subbasins should be taken into account during evaluation of their state, nature management projects, and other peatland research works.

  12. Development of Historical Water Table Maps of the 200 West Area of the Hanford Site (1950-1970)

    International Nuclear Information System (INIS)

    Kinney, Teena M.; McDonald, John P.

    2006-01-01

    A series of detailed historical water-table maps for the 200-West Area of the Hanford Site was made to aid interpretation of contaminant distribution in the upper aquifer. The contaminants are the result of disposal of large volumes of waste to the ground during Hanford Site operations, which began in 1944 and continued into the mid-1990s. Examination of the contaminant plumes that currently exist on site shows that the groundwater beneath the 200-West Area has deviated from its pre-Hanford west-to-east flow direction during the past 50 years. By using historical water-level measurements from wells around the 200-West Area, it was possible to create water-table contour maps that show probable historic flow directions. These maps are more detailed than previously published water-table maps that encompass the entire Hanford Site.

  13. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips - Part 1: nonuniform infiltration and soil water redistribution

    OpenAIRE

    Munoz Carpena, R.; Lauvernet, C.; Carluer, N.

    2018-01-01

    Vegetation buffers like vegetative filter strips (VFSs) are often used to protect water bodies from surface runoff pollution from disturbed areas. Their typical placement in floodplains often results in the presence of a seasonal shallow water table (WT) that can decrease soil infiltration and increase surface pollutant transport during a rainfall-runoff event. Simple and robust components of hydrological models are needed to analyze the impacts of WT in the landscape. To si...

  14. CORRELATION BETWEEN RAINFALL PATTERNS AND THE WATER TABLE IN THE GENERAL SEPARATIONS AREA OF THE SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    Smith, C.

    2009-01-01

    The objective of the study was to evaluate rainfall and water table elevation data in search of a correlation that could be used to understand and predict water elevation changes. This information will be useful in placing screen zones for future monitoring wells and operations of groundwater treatment units. Fifteen wells in the General Separations Area (GSA) at Savannah River Site were evaluated from 1986 through 2001. The study revealed that the water table does respond to rainfall with minimal delay. (Water level information was available monthly, which restricted the ability to evaluate a shorter delay period.) Water elevations were found to be related to the cumulative sum (Q-Delta Sum) of the difference between the average rainfall for a specific month and the actual rainfall for that month, calculated from an arbitrary starting point. Water table elevations could also be correlated between wells, but using the right well for correlation was very important. The strongest correlation utilized a quadratic equation that takes into account the rainfall in a specific area and the rainfall from an adjacent area that contributes through a horizontal flow. Specific values vary from well to well as a result of geometry and underground variations. R2's for the best models ranged up to 0.96. The data in the report references only GSA wells but other wells (including confined water tables) on the site have been observed to return similar water level fluctuation patterns

  15. Study of energy transfer in table-top X-pinch driven by a water line

    International Nuclear Information System (INIS)

    Beg, F N; Zhang, T; Fedin, D; Beagen, B; Chua, E; Lee, J Y; Rawat, R S; Lee, P

    2007-01-01

    The current passing through X-pinches and the energy transferring from the pulse forming line to the load are modelled using a simple LCR circuit. A comparison of the electrical properties of two table-top X-pinch devices is made. It was found that up to 25% of the stored energy is transferred from the water transmission line to the load in the University of California,San Diego (UCSD) table-top X-pinch before x-ray emission starts. The highest energy transmitted (75%) is found after the current peak. In comparison, only 3% of the energy is transferred to the load in the National Institute of Education (NIE) X-pinch device just after the maximum current peak. The highest energy (25%) transmitted to the plasma occurs long after the current peak. The plasma in both devices is visually and qualitatively similar. However, the UCSD device emits intense x-rays with no x-rays observed in the NIE device. This observation is consistent with the electrical circuit analysis

  16. Precipitation patterns and moisture fluxes in a sandy, tropical environment with a shallow water table

    Science.gov (United States)

    Minihane, M. R.; Freyberg, D. L.

    2011-08-01

    Identifying the dominant mechanisms controlling recharge in shallow sandy soils in tropical climates has received relatively little attention. Given the expansion of coastal fill using marine sands and the growth of coastal populations throughout the tropics, there is a need to better understand the nature of water balances in these settings. We use time series of field observations at a coastal landfill in Singapore coupled with numerical modeling using the Richards' equation to examine the impact of precipitation patterns on soil moisture dynamics, including percolation past the root zone and recharge, in such an environment. A threshold in total precipitation event depth, much more so than peak precipitation intensity, is the strongest event control on recharge. However, shallow antecedent moisture, and therefore the timing between events along with the seasonal depth to water table, also play significant roles in determining recharge amounts. For example, at our field site, precipitation events of less than 3 mm per event yield little to no direct recharge, but for larger events, moisture content changes below the root zone are linearly correlated to the product of the average antecedent moisture content and the total event precipitation. Therefore, water resources planners need to consider identifying threshold precipitation volumes, along with the multiple time scales that capture variability in event antecedent conditions and storm frequency in assessing the role of recharge in coastal water balances in tropical settings.

  17. Global lower mesospheric water vapor revealed by LIMS observations

    Science.gov (United States)

    Gordley, L. L.; Russell, J. M., III; Remsberg, E. E.

    1985-01-01

    The Limb Infrared Monitor of the Stratospheric water vapor channel data analysis has been extended from the 1. mb level (about 48 km) to the .3 mb level (about 60 km) through a radiance averaging procedure and better understanding of systematic errors. The data show H2O mixing ratio peaks near the .5 mb level varying from 4 to 7 ppmv with latitude and season. Above this level the mixing ratio drops off quickly with altitude, but, due to experimental uncertainties, at an uncertain rate. The stratospheric results are virtually the same as determined from the archived LIMS results with a tropical hygropause and enhanced H2O concentration in the lower levels at high winter latitudes.

  18. Moderate drop in water table increases peatland vulnerability to post-fire regime shift.

    Science.gov (United States)

    Kettridge, N; Turetsky, M R; Sherwood, J H; Thompson, D K; Miller, C A; Benscoter, B W; Flannigan, M D; Wotton, B M; Waddington, J M

    2015-01-27

    Northern and tropical peatlands represent a globally significant carbon reserve accumulated over thousands of years of waterlogged conditions. It is unclear whether moderate drying predicted for northern peatlands will stimulate burning and carbon losses as has occurred in their smaller tropical counterparts where the carbon legacy has been destabilized due to severe drainage and deep peat fires. Capitalizing on a unique long-term experiment, we quantify the post-wildfire recovery of a northern peatland subjected to decadal drainage. We show that the moderate drop in water table position predicted for most northern regions triggers a shift in vegetation composition previously observed within only severely disturbed tropical peatlands. The combined impact of moderate drainage followed by wildfire converted the low productivity, moss-dominated peatland to a non-carbon accumulating shrub-grass ecosystem. This new ecosystem is likely to experience a low intensity, high frequency wildfire regime, which will further deplete the legacy of stored peat carbon.

  19. Iron-mediated soil carbon response to water-table decline in an alpine wetland

    Science.gov (United States)

    Wang, Yiyun; Wang, Hao; He, Jin-Sheng; Feng, Xiaojuan

    2017-06-01

    The tremendous reservoir of soil organic carbon (SOC) in wetlands is being threatened by water-table decline (WTD) globally. However, the SOC response to WTD remains highly uncertain. Here we examine the under-investigated role of iron (Fe) in mediating soil enzyme activity and lignin stabilization in a mesocosm WTD experiment in an alpine wetland. In contrast to the classic `enzyme latch' theory, phenol oxidative activity is mainly controlled by ferrous iron [Fe(II)] and declines with WTD, leading to an accumulation of dissolvable aromatics and a reduced activity of hydrolytic enzyme. Furthermore, using dithionite to remove Fe oxides, we observe a significant increase of Fe-protected lignin phenols in the air-exposed soils. Fe oxidation hence acts as an `iron gate' against the `enzyme latch' in regulating wetland SOC dynamics under oxygen exposure. This newly recognized mechanism may be key to predicting wetland soil carbon storage with intensified WTD in a changing climate.

  20. Electrical Resistivity Imaging of Tidal Fluctuations in the Water Table at Inwood Hill Park, Manhattan

    Science.gov (United States)

    Kenyon, P. M.; Kassem, D.; Olin, A.; Nunez, J.; Smalling, A.

    2005-05-01

    Inwood Hill Park is located on the northern tip of Manhattan and has been extensively modified over the years by human activities. In its current form, it has a backbone of exposed or lightly covered bedrock along the Hudson River, adjacent to a flat area with two tidal inlets along the northern shore of Manhattan. The tidal motions in the inlets are expected to drive corresponding fluctuations in the water table along the borders of the inlets. In the Fall of 2002, a group of students from the Department of Earth and Atmospheric Sciences at the City College of New York studied these fluctuations. Electrical resistivity cross sections were obtained with a Syscal Kid Switch 24 resistivity meter during the course of a tidal cycle at three locations surrounding the westernmost inlet in the park. No change was seen over a tidal cycle at Site 1, possibly due to the effect of concrete erosion barriers which were located between the land and the water surrounding this site. Measurements at Site 2 revealed a small, regular change in the water table elevation of approximately 5 cm over the course of a tidal cycle. This site is inferred to rest on alluvial sediments deposited by a small creek. The cross sections taken at different times during a tidal cycle at Site 3 were the most interesting. They show a very heterogeneous subsurface, with water spurting between blocks of high resistivity materials during the rising portion of the cycle. A small sinkhole was observed on the surface of the ground directly above an obvious plume of water in the cross section. Park personnel confirmed that this sinkhole, like others scattered around this site, is natural and not due to recent construction activity. They also indicated that debris from the construction of the New York City subways may have been dumped in the area in the past. Our conclusion is that the tidal fluctuations at Site 3 are being channeled by solid blocks in the construction debris, and that the sinkholes currently

  1. Bathymetric maps and water-quality profiles of Table Rock and North Saluda Reservoirs, Greenville County, South Carolina

    Science.gov (United States)

    Clark, Jimmy M.; Journey, Celeste A.; Nagle, Doug D.; Lanier, Timothy H.

    2014-01-01

    Lakes and reservoirs are the water-supply source for many communities. As such, water-resource managers that oversee these water supplies require monitoring of the quantity and quality of the resource. Monitoring information can be used to assess the basic conditions within the reservoir and to establish a reliable estimate of storage capacity. In April and May 2013, a global navigation satellite system receiver and fathometer were used to collect bathymetric data, and an autonomous underwater vehicle was used to collect water-quality and bathymetric data at Table Rock Reservoir and North Saluda Reservoir in Greenville County, South Carolina. These bathymetric data were used to create a bathymetric contour map and stage-area and stage-volume relation tables for each reservoir. Additionally, statistical summaries of the water-quality data were used to provide a general description of water-quality conditions in the reservoirs.

  2. Culture of microalgae biomass for valorization of table olive processing water

    International Nuclear Information System (INIS)

    Contreras, C.G.; Serrano, A.; Ruiz-Filippi, G.; Borja, R.; Fermoso, F.G.

    2016-01-01

    Table olive processing water (TOPW) contains many complex substances, such as phenols, which could be valorized as a substrate for microalgae biomass culture. The aim of this study was to assess the capability of Nannochloropsis gaditana to grow in TOPW at different concentrations (10- 80%) in order to valorize this processing water. Within this range, the highest increment of biomass was determined at percentage of 40% of TOPW, reaching an increment of 0.36 ± 0.05 mg volatile suspended solids (VSS)/L. Components of algal biomass were similar for the experiments at 10-40% of TOPW, where proteins were the major compounds (56-74%). Total phenols were retained in the microalgae biomass (0.020 ± 0.002 g of total phenols/g VSS). Experiments for 80% of TOPW resulted in a low production of microalgae biomass. High organic matter, nitrogen, phosphorus and phenol removal were achieved in all TOPW concentrations. Although high-value products, such as proteins, were obtained and high removal efficiencies of nutrients were determined, microalgae biomass culture should be enhanced to become a suitable integral processing water treatment. [es

  3. A Modified Water-Table Fluctuation Method to Characterize Regional Groundwater Discharge

    Directory of Open Access Journals (Sweden)

    Lihong Yang

    2018-04-01

    Full Text Available A modified Water-Table Fluctuation (WTF method is developed to quantitatively characterize the regional groundwater discharge patterns in stressed aquifers caused by intensive agricultural pumping. Two new parameters are defined to express the secondary information in the observed data. One is infiltration efficiency and the other is discharge modulus (recurring head loss due to aquifer discharge. An optimization procedure is involved to estimate these parameters, based on continuous groundwater head measurements and precipitation records. Using the defined parameters and precipitation time series, water level changes are calculated for individual wells with fidelity. The estimated parameters are then used to further address the characterization of infiltration and to better quantify the discharge at the regional scale. The advantage of this method is that it considers recharge and discharge simultaneously, whereas the general WTF methods mostly focus on recharge. In the case study, the infiltration efficiency reveals that the infiltration is regionally controlled by the intrinsic characteristics of the aquifer, and locally distorted by engineered hydraulic structures that alter surface water-groundwater interactions. The seasonality of groundwater discharge is characterized by the monthly discharge modulus. These results from individual wells are clustered into groups that are consistent with the local land use pattern and cropping structures.

  4. Effects of high-rate wastewater spray disposal on the water-table aquifer, Hilton Head Island, South Carolina

    Science.gov (United States)

    Speiran, G.K.

    1985-01-01

    A study by the U.S. Geological Survey from April 1982 through December 1983 evaluated the effects of high-rate disposal of treated wastewater on the water table aquifer, Hilton Head Island, South Carolina. Flooding of topographically low areas resulted from the application of 10.8 inches of wastewater in 10 days in January 1983. The water table remained 2-1/2 to 5-1/2 feet below land surface when wastewater was applied at rates of 5 inches per week in August and December 1983. (USGS)

  5. Ground-water sampling of the NNWSI (Nevada Nuclear Waste Storage Investigation) water table test wells surrounding Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Matuska, N.A.

    1988-12-01

    The US Geological Survey (USGS), as part of the Nevada Nuclear Waste Storage Investigation (NNWSI) study of the water table in the vicinity of Yucca Mountain, completed 16 test holes on the Nevada Test Site and Bureau of Land Management-administered lands surrounding Yucca Mountain. These 16 wells are monitored by the USGS for water-level data; however, they had not been sampled for ground-water chemistry or isotropic composition. As part of the review of the proposed Yucca Mountain high-level nuclear waste repository, the Desert Research Institute (DRI) sampled six of these wells. The goal of this sampling program was to measure field-dependent parameters of the water such as electrical conductivity, pH, temperature and dissolved oxygen, and to collect samples for major and minor element chemistry and isotopic analysis. This information will be used as part of a program to geochemically model the flow direction between the volcanic tuff aquifers and the underlying regional carbonate aquifer

  6. Large-scale regionalization of water table depth in peatlands optimized for greenhouse gas emission upscaling

    Science.gov (United States)

    Bechtold, M.; Tiemeyer, B.; Laggner, A.; Leppelt, T.; Frahm, E.; Belting, S.

    2014-09-01

    Fluxes of the three main greenhouse gases (GHG) CO2, CH4 and N2O from peat and other soils with high organic carbon contents are strongly controlled by water table depth. Information about the spatial distribution of water level is thus a crucial input parameter when upscaling GHG emissions to large scales. Here, we investigate the potential of statistical modeling for the regionalization of water levels in organic soils when data covers only a small fraction of the peatlands of the final map. Our study area is Germany. Phreatic water level data from 53 peatlands in Germany were compiled in a new data set comprising 1094 dip wells and 7155 years of data. For each dip well, numerous possible predictor variables were determined using nationally available data sources, which included information about land cover, ditch network, protected areas, topography, peatland characteristics and climatic boundary conditions. We applied boosted regression trees to identify dependencies between predictor variables and dip-well-specific long-term annual mean water level (WL) as well as a transformed form (WLt). The latter was obtained by assuming a hypothetical GHG transfer function and is linearly related to GHG emissions. Our results demonstrate that model calibration on WLt is superior. It increases the explained variance of the water level in the sensitive range for GHG emissions and avoids model bias in subsequent GHG upscaling. The final model explained 45% of WLt variance and was built on nine predictor variables that are based on information about land cover, peatland characteristics, drainage network, topography and climatic boundary conditions. Their individual effects on WLt and the observed parameter interactions provide insight into natural and anthropogenic boundary conditions that control water levels in organic soils. Our study also demonstrates that a large fraction of the observed WLt variance cannot be explained by nationally available predictor variables and

  7. Luminescence imaging of water during irradiation of X-ray photons lower energy than Cerenkov- light threshold

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi; Koyama, Shuji; Komori, Masataka [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Toshito, Toshiyuki [Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya City West Medical Center (Japan)

    2016-10-01

    Luminescence imaging of water using X-ray photon irradiation at energy lower than maximum energy of ~200 keV is thought to be impossible because the secondary electrons produced in this energy range do not emit Cerenkov- light. Contrary to this consensus assumption, we show that the luminescence imaging of water can be achieved by X-ray irradiation at energy lower than 120 keV. We placed water phantoms on a table with a conventional X-ray imaging system, and luminescence images of these phantoms were measured with a high-sensitivity, cooled charge coupled device (CCD) camera during X-ray photon irradiation at energy below 120 keV. We also carried out such imaging of an acrylic block and plastic scintillator. The luminescence images of water phantoms taken during X-ray photon irradiation clearly showed X-ray photon distribution. The intensity of the X-ray photon images of the phantom increased almost proportionally to the number of X-ray irradiations. Lower-energy X-ray photon irradiation showed lower-intensity luminescence at the deeper parts of the phantom due to the higher X-ray absorption in the water phantom. Furthermore, lower-intensity luminescence also appeared at the deeper parts of the acrylic phantom due to its higher density than water. The intensity of the luminescence for water was 0.005% of that for plastic scintillator. Luminescence imaging of water during X-ray photon irradiation at energy lower than 120 keV was possible. This luminescence imaging method is promising for dose estimation in X-ray imaging systems.

  8. Luminescence imaging of water during irradiation of X-ray photons lower energy than Cerenkov- light threshold

    Science.gov (United States)

    Yamamoto, Seiichi; Koyama, Shuji; Komori, Masataka; Toshito, Toshiyuki

    2016-10-01

    Luminescence imaging of water using X-ray photon irradiation at energy lower than maximum energy of 200 keV is thought to be impossible because the secondary electrons produced in this energy range do not emit Cerenkov- light. Contrary to this consensus assumption, we show that the luminescence imaging of water can be achieved by X-ray irradiation at energy lower than 120 keV. We placed water phantoms on a table with a conventional X-ray imaging system, and luminescence images of these phantoms were measured with a high-sensitivity, cooled charge coupled device (CCD) camera during X-ray photon irradiation at energy below 120 keV. We also carried out such imaging of an acrylic block and plastic scintillator. The luminescence images of water phantoms taken during X-ray photon irradiation clearly showed X-ray photon distribution. The intensity of the X-ray photon images of the phantom increased almost proportionally to the number of X-ray irradiations. Lower-energy X-ray photon irradiation showed lower-intensity luminescence at the deeper parts of the phantom due to the higher X-ray absorption in the water phantom. Furthermore, lower-intensity luminescence also appeared at the deeper parts of the acrylic phantom due to its higher density than water. The intensity of the luminescence for water was 0.005% of that for plastic scintillator. Luminescence imaging of water during X-ray photon irradiation at energy lower than 120 keV was possible. This luminescence imaging method is promising for dose estimation in X-ray imaging systems.

  9. Upper Bound Solution for the Face Stability of Shield Tunnel below the Water Table

    Directory of Open Access Journals (Sweden)

    Xilin Lu

    2014-01-01

    Full Text Available By FE simulation with Mohr-Coulomb perfect elastoplasticity model, the relationship between the support pressure and displacement of the shield tunnel face was obtained. According to the plastic strain distribution at collapse state, an appropriate failure mechanism was proposed for upper bound limit analysis, and the formula to calculate the limit support pressure was deduced. The limit support pressure was rearranged to be the summation of soil cohesion c, surcharge load q, and soil gravity γ multiplied by their corresponding coefficients Nc, Nq, and Nγ, and parametric studies were carried out on these coefficients. In order to consider the influence of seepage on the face stability, the pore water pressure distribution and the seepage force on the tunnel face were obtained by FE simulation. After adding the power of seepage force into the equation of the upper bound limit analysis, the total limit support pressure for stabilizing the tunnel face under seepage condition was obtained. The total limit support pressure was shown to increase almost linearly with the water table.

  10. Non-methane biogenic volatile organic compound emissions from boreal peatland microcosms under warming and water table drawdown

    DEFF Research Database (Denmark)

    Faubert, P; Tiiva, P; Nakam, TA

    2011-01-01

    assessed the combined effect of warming and water table drawdown on the BVOC emissions from boreal peatland microcosms. We also assessed the treatment effects on the BVOC emissions from the peat soil after the 7-week long experiment. Emissions of isoprene, monoterpenes, sesquiterpenes, other reactive VOCs...

  11. The leaching of radioactivity from highly radioactive glass blocks buried below the water table: fifteen years of results

    International Nuclear Information System (INIS)

    Merritt, W.F.

    1976-03-01

    The results from two test burials of high-level fission products incorporated into nepheline syenite glass indicate that the nuclear wastes from fuel processing for a 30,000 MWe nuclear power industry could be incorporated into such glass and stored beneath the water table in the waste management area of Chalk River Nuclear Laboratories (CRNL) without harm to the environment. (author)

  12. Water table response to harvesting and simulated emerald ash borer mortality in black ash wetlands in Minnesota, USA

    Science.gov (United States)

    Robert A. Slesak; Christian F. Lenhart; Kenneth N. Brooks; Anthony W. D' Amato; Brian J. Palik

    2014-01-01

    Black ash wetlands are seriously threatened because of the invasive emerald ash borer (EAB). Wetland hydrology is likely to be modified following ash mortality, but the magnitude of hydrological impact following loss via EAB and alternative mitigation harvests is not clear. Our objective was to assess the water table response to simulated EAB and harvesting to...

  13. Spectral detection of near-surface moisture content and water-table position in northern peatland ecosystems

    Science.gov (United States)

    Karl M. Meingast; Michael J. Falkowski; Evan S. Kane; Lynette R. Potvin; Brian W. Benscoter; Alistair M.S. Smith; Laura L. Bourgeau-Chavez; Mary Ellen. Miller

    2014-01-01

    Wildland fire occurrence has been increasing in peatland ecosystems during recent decades. As such, there is a need for broadly applicable tools to detect and monitor controls on combustion such as surface peat moisture and water-table position. A field portable spectroradiometer was used to measure surface reflectance of two Sphagnum moss-dominated...

  14. Ecosystem respiration in a heterogeneous temperate peatland and its sensitivity to peat temperature and water table depth

    Czech Academy of Sciences Publication Activity Database

    Juszczak, R.; Humphreys, E.; Acosta, Manuel; Michalak-Galczewska, M.; Kayzer, D.; Olejnik, Janusz

    2013-01-01

    Roč. 366, 1-2 (2013), s. 505-520 ISSN 0032-079X Institutional support: RVO:67179843 Keywords : Ecosystem respiration * Geogenous peatland * Chamber measurements * CO2 fluxes * Water table depth Subject RIV: EH - Ecology, Behaviour Impact factor: 3.235, year: 2013

  15. Interactive plant functional group and water table effects on decomposition and extracellular enzyme activity in Sphagnum peatlands

    Science.gov (United States)

    Magdalena M. Wiedermann; Evan S. Kane; Lynette R. Potvin; Erik A. Lilleskov

    2017-01-01

    Peatland decomposition may be altered by hydrology and plant functional groups (PFGs), but exactly how the latter influences decomposition is unclear, as are potential interactions of these factors.We used a factorial mesocosm experiment with intact 1 m3 peat monoliths to explore how PFGs (sedges vs Ericaceae) and water table level individually...

  16. LITHOLOGIC CONDITIONS OF THE WATER TABLE LOGGING IN THE AREA OF HAĆKI VILLAGE IN THE BIELSKA PLAIN

    Directory of Open Access Journals (Sweden)

    Krzysztof Micun

    2016-05-01

    Full Text Available The aim of the study was to examine lithological conditions of the water table in the area of Haćki village located in the Bielska Plain. The study involved the measurements of water level in dug wells, hand drill probing to a depth of 5 m, acquiring the samples of water-bearing deposits and analysing their granulation. The results of analyses allowed to calculate the permeability coefficient. The geological structure of the area is dominated by dusty deposits of various origins. Such deposits’ formation directly affects the conditions of filtration and depth of the water table. Groundwater logging near Haćki village in the Bielska Plain appears at a depth of several tens of centimeters to 2 meters in the depressions field and up a little over 5 meters in the case of higher ground surfaces. The presence of perched water was revealed on the hills, periodic leachates at the foot of the hills and scarps and one periodic spring. Water-bearing deposits are medium sands, fine sands and loamy fine sands or fine sands with silt. Consequently, the permeability coefficient is low or even very low. Its values range from 0,001 m·d-1 to 3,8 m·d-1 (d – 24 hours. The widespread presence of dusty deposits in the area affects the limited efficiency of the water table.

  17. Basic prerequisites and the practice of using deep water tables for burying liquid radioactive wastes

    International Nuclear Information System (INIS)

    Spitsyn, V.I.; Pimenov, M.K.; Balukova, V.D.; Leontichuk, A.S.; Kokorin, I.N.; Yudin, F.P.; Rakov, N.A.

    In the USSR, creating reservoirs for liquid radioactive wastes is one of the promising methods of safely disposing of them in deep water tables, in zones with a standing regime or a slow rate of subterranean water exchange. The results of investigations and the practice of burying (the wastes) indicate the reliability and effectiveness of such a method of final waste disposal when the basic requirements of environmental protection are observed. Geological formations and collector strata that guarantee the localization of the liquid radioactive wastes placed in them for many tens and even hundreds of thousands of years can be studied and chosen in different regions. The basic requirements and criteria to which the geological structures and collector strata must correspond for ensuring the safe burial of wastes have been formulated. Wastes are buried only after a comprehensive, scientifically based evaluation of the sanitary-radiation safety for this generation and future ones, taking into account the burial regime and the physico-chemical processes that accompany combining wastes with rocks and stratal waters, as well as the time of holding wastes to maximum permissible concentrations. Positive and negative factors that characterize the method are analyzed. Possible emergency situations with subterranean burial are evaluated. The composition and methods of the geological survey, hydrodynamic, geophysical, physico-chemical and sanitary-radiation investigations; methods of calculating and predicting the movement of wastes underground;methods of preparing wastes for burial and chemical methods of restoring the suitability of wells; design characteristics and conditions of preparing wells for use; methods of estimating heating and processes of radiolysis for a medium containing highly radioactive wastes; methods of operational and remote control of the burial process and the condition of the ambient medium, etc. are briefly examined

  18. Isotopic fractionation of soil water during the evaporation process in the presence of a phreatic water table

    International Nuclear Information System (INIS)

    Leopoldo, P.R.; Stolf, R.

    1979-01-01

    This experiment was conducted with columns of soil, constitued by alluvion sediment keeping a phreatic watertable at a depth of 40 cm and constant water supply, and its objective was to check the water behaviour as to its deuterium and oxigen content when moving from the lower layers to the upper layers, and consequent loss to the atmosphere through evaporation. It was noted that the existing D and 18 O content in the water forming the phreativ watertable practivally does not vary with this process. In addition to the observations on soil columns, soil water from the Brasilian northeastern region was collected and analysed. The phreatic watertable at the collecting site lay at a depth of about 40-50 cm. Preliminarily, it was noted that these results apparently indicate an excess evaporation, and are also consistent with those obtained by other investigators, who proposed the use of stable isotopes to study problems related to salinization of water in this region. (Author) [pt

  19. Water resources inventory of Connecticut Part 3: lower Thames and southeastern coastal river basins

    Science.gov (United States)

    Thomas, Chester E.; Cervione, Michael A.; Grossman, I.G.

    1968-01-01

    The lower Thames and southeastern coastal river basins have a relatively abundant supply of water of generally good quality which is derived from streams entering the area and precipitation that has fallen on the area. Annual precipitation has ranged from about 32 inches to 65 inches and has averaged about 48 inches over a 30-year period. Approximately 22 inches of water are returned to the atmosphere each year by evaporation and transpiration; the remainder of the annual precipitation either flows overland to streams or percolates downward to the water table and ultimately flows out of the report area through estuaries and coastal streams or as underflow through the deposits beneath. During the autumn and winter months precipitation normally is sufficient to cause a substantial increase in the amount of water stored underground and in surface reservoirs within the report area, whereas in the summer most of the precipitation is lost through evaporation and transpiration, resulting in sharply reduced stream-flow and lowered ground-water levels. The mean monthly storage of water on an average is about 3.8 inches higher in November than it is in June. The amount of water that flows through and out of the report area represents the total amount of water potentially available for use by man. For the 30-year period 1931 through 1960, the annual runoff from the report area has averaged nearly 26 inches (200 billion gallons), from the entire Thames River basin above Norwich about 24 inches (530 billion gallons), and from the Pawcatuck River basin about 26 inches (130 billion gallons). A total average annual runoff of 860 billion gallons is therefore available. Although runoff indicates the total amount of water potentially available, it is usually not economically feasible for man to use all of it. On the other hand, with increased development, it is possible that some water will be reused several times. The water available may be tapped as it flows through the area or is

  20. Effects of water table position and plant functional group on plant community, aboveground production, and peat properties in a peatland mesocosm experiment (PEATcosm)

    Science.gov (United States)

    Lynette R. Potvin; Evan S. Kane; Rodney A. Chimner; Randall K. Kolka; Erik A. Lilleskov

    2015-01-01

    Aims Our objective was to assess the impacts of water table position and plant functional type on peat structure, plant community composition and aboveground plant production. Methods We initiated a full factorial experiment with 2 water table (WT) treatments (high and low) and 3 plant functional groups (PFG: sedge, Ericaceae,...

  1. Estimating evapotranspiration and groundwater flow from water-table fluctuations for a general wetland scenario

    Science.gov (United States)

    Weber, Lisa C.; Wiley, Michael J.; Wilcox, Douglas A.

    2016-01-01

    The use of diurnal water-table fluctuation methods to calculate evapotranspiration (ET) and groundwater flow is of increasing interest in ecohydrological studies. Most studies of this type, however, have been located in riparian wetlands of semi-arid regions where groundwater levels are consistently below topographic surface elevations and precipitation events are infrequent. Current methodologies preclude application to a wider variety of wetland systems. In this study, we extended a method for estimating sub-daily ET and groundwater flow rates from water-level fluctuations to fit highly dynamic, non-riparian wetland scenarios. Modifications included (1) varying the specific yield to account for periodic flooded conditions and (2) relating empirically derived ET to estimated potential ET for days when precipitation events masked the diurnal signal. To demonstrate the utility of this method, we estimated ET and groundwater fluxes over two growing seasons (2006–2007) in 15 wetlands within a ridge-and-swale wetland complex of the Laurentian Great Lakes under flooded and non-flooded conditions. Mean daily ET rates for the sites ranged from 4.0 mm d−1 to 6.6 mm d−1. Shallow groundwater discharge rates resulting from evaporative demand ranged from 2.5 mm d−1 to 4.3 mm d−1. This study helps to expand our understanding of the evapotranspirative demand of plants under various hydrologic and climate conditions. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  2. [The marketing evaluation of the consumers' preference as regards the use of medicinal and medicinal table mineral waters].

    Science.gov (United States)

    Babaskin, D V; Babaskina, L I; Pavlova, A V

    2017-12-28

    The development of modern technologies in physiotherapy with the use of mineral waters, the expansion of the assortment of the medicinal and medicinal table waters as well as increasing the competitive advantages of domestic products require the more extensive marketing survey of the consumers' preferences in the market of mineral waters. The objective of the present study was the marketing evaluation of the consumers' preference in the segment of medicinal and medicinal table mineral waters in the city of Moscow. The survey involved 697 consumers of medicinal and medicinal table mineral waters. The sampling was carried out by the deterministic quota method. The field research was conducted by means of personal verbal interviews (32%) and the CATI to Web method (phone recruiting and on-line questioning) (68%) with the use of the structured questionnaire. Positioning was carried out making use of the two-dimensional schematic map and scoring assessment on an individual basis with calculation of integrated indicators. The marketing evaluation has demonstrated that the principal motive for purchasing mineral waters in more than 40% of respondents was the treatment and prevention of various diseases including disturbances in the urogenital system as well as digestive and respiratory disorders that appear to be the most frequent reasons for the consumption of mineral waters. The main factors that form the preferences of the consumers as regards the use of a concrete variety of mineral waters were elucidated. Of crucial importance for approximately 40% of the consumers (p<0.01) proved to be their health condition, the medical indications, and the available information about the therapeutic effectiveness of one or another type of mineral waters. Other factors were the quality of mineral water, its cost, the manufacturer and/or place of production, the attractiveness of the packaging, etc. The evaluation of the positioning of the mineral water consumers' preferences made

  3. Occurrence and parameters of frequency of Legionella in warm water systems of hospitals and hotels in Lower Saxony.

    Science.gov (United States)

    Habicht, W; Müller, H E

    1988-03-01

    A total of 1241 water samples was investigated from 103 hospitals and 62 hotels in Lower Saxony 1985-87. 331 of 949 samples from hospitals and 26 of 292 samples from hotels were Legionella positive. All together 70% of the hospitals and 18% of the hotels investigated were Legionella positive, and 836 strains of Legionella were isolated (Table 1). As they could be diagnosed they belong to L. pneumophila SG1 306 strains, SG2 36 strains, SG3 127 strains, SG4 45 strain, SG5 29 strain, SG6 106 strains, SG9 13 strains and SG10 13 strains. Further 134 strains belonging to L. pneumophila but not to SG1-SG12 show cross reactions with serogroups 5, 8, and 10. Finally, 16 strains belong to L. dumoffii and 1 strain to L. anisa (Table 2). The following parameters of water samples were studied, too: temperature, pH value, conductivity, concentration of iron, of organic matter, of other bacteria, occurrence of amoebas, and the materials of water plumbing systems. Most samples contained concentrations of Legionella in the range of 10(1)-10(3) CFU/ml, highest concentrations were 10(5) CFU/ml (Fig. 1). Most frequently, Legionella were isolated within the range of temperature of 35-45 degrees C. However, a few of the water samples were positive for Legionella even up to 66 degrees C (Fig. 3). The conductivity has no and the pH value (Fig. 2) has only little influence on the occurrence of Legionella. There is a positive correlation between concentration of iron and frequency of Legionella (Fig. 4). Also organic matter (Fig. 6) and amoebas (Table 3) seem to enhance the occurrence of Legionella. Plumbing systems consisting of copper showed an inhibitory effect on Legionella during the first five years, whereas no effect could be detected in older systems (Fig. 5).

  4. Water Table Depth Reconstruction in Ombrotrophic Peatlands Using Biomarker Abundance Ratios and Compound-Specific Hydrogen Isotope Composition

    Science.gov (United States)

    Nichols, J. E.; Jackson, S. T.; Booth, R. K.; Pendall, E. G.; Huang, Y.

    2005-12-01

    Sediment cores from ombrotrophic peat bogs provide sensitive records of changes in precipitation/evaporation (P/E) balance. Various proxies have been developed to reconstruct surface moisture conditions in peat bogs, including testate amoebae, plant macrofossils, and peat humification. Studying species composition of testate amoeba assemblages is time consuming and requires specialized training. Humification index can be influenced by environmental factors other than moisture balance. The plant macrofossil proxy is less quantitative and cannot be performed on highly decomposed samples. We demonstrate that the ratio of C23 alkane to C29 alkane abundance may provide a simple alternative or complementary means of tracking peatland water-table depth. Data for this proxy can be collected quickly using a small sample (100 mg dry). Water-table depth decreases during drought, and abundance of Sphagnum, the dominant peat-forming genus, decreases as vascular plants increase. Sphagnum moss produces mainly medium chain-length alkanes (C21-C25) while vascular plants (grasses and shrubs) produce primarily longer chain-length alkanes (C27-C31). Therefore, C23:C29 n-alkane ratios quantitatively track the water table depth fluctuations in peat bogs. We compared C23:C29 n-alkane ratios in a core from Minden Bog (southeastern Michigan) with water table depth reconstructions based on testate-amoeba assemblages and humification. The 184-cm core spans the past ~3kyr of continuous peat deposition in the bog. Our results indicate that the alkane ratios closely track the water table depth variations, with C29 most abundant during droughts. We also explored the use of D/H ratios in Sphagnum biomarkers as a water-table depth proxy. Compound-specific hydrogen isotope ratio analyses were performed on Sphagnum biomarkers: C23 and C25 alkane and C24 acid. Dry periods are represented in these records by an enrichment of deuterium in these Sphagnum-specific compounds. These events also correlate

  5. Water Transport in Lower Hillsborough Bay, Florida, 1995-96

    National Research Council Canada - National Science Library

    Levesque, Victor A; Hammett, K. M

    1997-01-01

    .... Beginning in December 1994, a series of reconnaissance measurements were made to define the probable maximum extent of the area where it could be possible to discern water transport associated...

  6. Water requirements of sorghum in lower Euphrates basin

    International Nuclear Information System (INIS)

    Khalifa, Kh.

    1993-01-01

    Field experiments were conducted for two years during July 1987 and 1988 at the Research Station of ACSAD near Deir-Ezzor. The objectives of this study were to determine water requirements and consumptive use of sorghum (Var-IZRA'A3). The treatments were three levels of soil moisture content at 30-45 cm soil layer at which irrigation was implemented I 1 , I 2 , I 3 , representing 80%, 70% and 60% of field capacity respectively. The moisture content in the different layers of soil was measured by neutron probe except the 0-15 cm layer, which was determined gravimetrically. Some chemical and physical characteristics of soil, moisture content in the soil before irrigation, consumptive use, coefficient of consumptive use, productivity of sorghum, efficiencies of irrigation, water, K-coefficient, rate of irrigation, amount of total water added to each treatment during growth season, were studied. The results indicate that treatment I 1 has higher grain and biomass (fresh weight) yield than I 2 and I 3 . The yields were 3.142, 2.678, 2.242 ton grain/ha and 40.1, 38.2, 25,1 ton biomass/ha for I 1 , I 2 , I 3 respectively as the mean for two seasons. The mean water requirements (total water added) and consumptive use during the two years 1987 and 1988 were: 6520.0, 4922.0 m 3 /ha and 6022.5, 4836.0, 4001.0 m 3 /ha for treatments I 1 , I 2 , and I 3 respectively. Water use efficiencies were 0.52, 0.56, 0.56 Kg grain/m 3 water, water application efficiencies were 0.92, 0.86, 0.80 and coefficient of consumptive use was 1.9, 1.80, 1.79 m 3 water/Kg grain for the first, second and third treatments respectively. Generally, the final results indicate that treatment I 1 , gives the highest yield among the others, the yield of grain was 3075.0 and 3210.2 Kg/ha for first and second year respectively. Therefore, we may suggest the use of I 1 for sorghum irrigation in Deir-Ezzor area. The proper percentage of soil moisture content at 30-45 cm depth to start irrigation is 80% of field

  7. Nitrogen Release in Pristine and Drained Peat Profiles in Response to Water Table Fluctuations: A Mesocosm Experiment

    Directory of Open Access Journals (Sweden)

    Merjo P. P. Laine

    2013-01-01

    Full Text Available In the northern hemisphere, variability in hydrological conditions was suggested to increase as a consequence of climate warming, which may result in longer droughts than the area has experienced before. Due to their predominately anoxic conditions, peatlands are expected to respond to changes in hydrological conditions, such as successive drying and rewetting periods. As peatlands are rich in organic matter, any major changes in water table may influence the decomposition of it. The hydrological conditions may also influence release of nutrients from peat profiles as well as affect their transport to downstream ecosystems. In our mesocosm experiment, artificial water table fluctuations in pristine peat profiles caused an increase in dissolved organic nitrogen (DON and ammonium (NH4+-N concentrations, while no response was found in drained peat profiles, although originating from the same peatland complex.

  8. Water resources inventory of Connecticut Part 10: Lower Connecticut River basin

    Science.gov (United States)

    Weiss, Lawrence A.; Bingham, James W.; Thomas, Mendall P.

    1982-01-01

    The lower Connecticut River basin study area in south-central Connecticut includes 639 square miles and is drained principally by the Connecticut River and by seven smaller streams that flow directly to Long Island Sound between the West River on the west and the Connecticut River on the east. The population in 1979 was estimated to be 210,380. Much of the industrial development and population centers are in the Mattabesset River basin in the northwestern part, and the largest water use is also in the Mattabesset River basin. Precipitation averages 47 inches per year and provides an abundant supply of water. About 20 inches returns to the atmosphere as evapotranspiration, and the remainder either flows directly to streams or percolates to the water table, eventually discharging to Long Island Sound. Small quantities of water are exported from the basin by the New Haven and Meridan Water Departments, and small quantities are imported by the New Britain Water Department and Metropolitan Direct Commission. Precipitation during 1931-60 resulted in an average annual runoff of 302 billion gallons. In inflow from the Connecticut River is added to the average annual runoff, the 4,370 billion gallon s per year is potentially available for water ue. The domestic, institutional, commercial, and industrial (other than cooling water) water use for 1970 was 7 billion gallons, which is only 3 percent of the total water used, whereas 97 percent of the total is cooling water for power plants. Approximately 60 percent of the 7 billion gallons is treated before being discharged back to the streams. The total amount of fresh water used during 1970 was estimated to be 256,000 million gallons (Mgal), of which 247,000 Mgal was used for cooling water at stream electric-generating plants. The quantity for domestic, commercial, industrial, and agricultural used was 9,000 Mgal, which was approximately 120 gallons a day per person. Public water systems providing 70 percent of these

  9. An analytical study on nested flow systems in a Tóthian basin with a periodically changing water table

    Science.gov (United States)

    Zhao, Ke-Yu; Jiang, Xiao-Wei; Wang, Xu-Sheng; Wan, Li; Wang, Jun-Zhi; Wang, Heng; Li, Hailong

    2018-01-01

    Classical understanding on basin-scale groundwater flow patterns is based on Tóth's findings of a single flow system in a unit basin (Tóth, 1962) and nested flow systems in a complex basin (Tóth, 1963), both of which were based on steady state models. Vandenberg (1980) extended Tóth (1962) by deriving a transient solution under a periodically changing water table in a unit basin and examined the flow field distortion under different dimensionless response time, τ∗. Following Vandenberg's (1980) approach, we extended Tóth (1963) by deriving the transient solution under a periodically changing water table in a complex basin and examined the transient behavior of nested flow systems. Due to the effect of specific storage, the flow field is asymmetric with respect to the midline, and the trajectory of internal stagnation points constitutes a non-enclosed loop, whose width decreases when τ∗ decreases. The distribution of the relative magnitude of hydraulic head fluctuation, Δh∗ , is dependent on the horizontal distance away from a divide and the depth below the land surface. In the shallow part, Δh∗ decreases from 1 at the divide to 0 at its neighboring valley under all τ∗, while in the deep part, Δh∗ reaches a threshold, whose value decreases when τ∗ increases. The zones with flowing wells are also found to change periodically. As water table falls, there is a general trend of shrinkage in the area of zones with flowing wells, which has a lag to the declining water table under a large τ∗. Although fluxes have not been assigned in our model, the recharge/discharge flux across the top boundary can be obtained. This study is critical to understand a series of periodically changing hydrogeological phenomena in large-scale basins.

  10. Assessment of denitrification gaseous end-products in the soil profile under two water table management practices using repeated measures analysis.

    Science.gov (United States)

    Elmi, Abdirashid A; Astatkie, Tess; Madramootoo, Chandra; Gordon, Robert; Burton, David

    2005-01-01

    The denitrification process and nitrous oxide (N2O) production in the soil profile are poorly documented because most research into denitrification has concentrated on the upper soil layer (0-0.15 m). This study, undertaken during the 1999 and 2000 growing seasons, was designed to examine the effects of water table management (WTM), nitrogen (N) application rate, and depth (0.15, 0.30, and 0.45 m) on soil denitrification end-products (N2O and N2) from a corn (Zea mays L.) field. Water table management treatments were free drainage (FD) with open drains and subirrigation (SI) with a target water table depth of 0.6 m. Fertility treatments (ammonium nitrate) were 120 kg N ha(-1) (N120) and 200 kg N ha(-1) (N200). During both growing seasons greater denitrification rates were measured in SI than in FD, particularly in the surface soil (0-0.15 m) and at the intermediate (0.15-0.30 m) soil depths under N200 treatment. Greater denitrification rates under the SI treatment, however, were not accompanied with greater N2O production. The decrease in N2O production under SI was probably caused by a more complete reduction of N2O to N2, which resulted in lower N2O to (N2O + N2) ratios. Denitrification rate, N2O production and N2O to (N2O + N2) ratios were only minimally affected by N treatments, irrespective of sampling date and soil depth. Overall, half of the denitrification occurred at the 0.15- to 0.30- and 0.30- to 0.45-m soil layers, and under SI, regardless of fertility treatment level. Consequently, sampling of the 0- to 0.15-m soil layer alone may not give an accurate estimation of denitrification losses under SI practice.

  11. Discoloration of polyvinyl chloride (PVC) tape as a proxy for water-table depth in peatlands: validation and assessment of seasonal variability

    Science.gov (United States)

    Booth, Robert K.; Hotchkiss, Sara C.; Wilcox, Douglas A.

    2005-01-01

    Summary: 1. Discoloration of polyvinyl chloride (PVC) tape has been used in peatland ecological and hydrological studies as an inexpensive way to monitor changes in water-table depth and reducing conditions. 2. We investigated the relationship between depth of PVC tape discoloration and measured water-table depth at monthly time steps during the growing season within nine kettle peatlands of northern Wisconsin. Our specific objectives were to: (1) determine if PVC discoloration is an accurate method of inferring water-table depth in Sphagnum-dominated kettle peatlands of the region; (2) assess seasonal variability in the accuracy of the method; and (3) determine if systematic differences in accuracy occurred among microhabitats, PVC tape colour and peatlands. 3. Our results indicated that PVC tape discoloration can be used to describe gradients of water-table depth in kettle peatlands. However, accuracy differed among the peatlands studied, and was systematically biased in early spring and late summer/autumn. Regardless of the month when the tape was installed, the highest elevations of PVC tape discoloration showed the strongest correlation with midsummer (around July) water-table depth and average water-table depth during the growing season. 4. The PVC tape discoloration method should be used cautiously when precise estimates are needed of seasonal changes in the water-table.

  12. Quality evaluation of commercially sold table water samples in Michael Okpara University of Agriculture, Umudike, Nigeria and surrounding environments

    Directory of Open Access Journals (Sweden)

    D.O. Okorie

    2015-01-01

    Full Text Available In Michael Okpara University of Agriculture, Umudike, Nigeria (MOUAU and surrounding environments, table water of different brands is commercially hawked by vendors. To the best of our knowledge, there is no scientific documentation on the quality of these water samples. Hence this study which evaluated the quality of different brands of water samples commercially sold in MOUAU and surrounding environments. The physicochemical properties (pH, total dissolved solids (TDS, biochemical oxygen demand (BOD, total hardness, dissolved oxygen, Cl, NO3, ammonium nitrogen (NH3N, turbidity, total suspended solids (TSS, Ca, Mg, Na and K of the water samples as indices of their quality were carried out using standard techniques. Results obtained from this study indicated that most of the chemical constituents of these table water samples commercially sold in Umudike environment conformed to the standards given by the Nigerian Industrial Standard (NIS, World Health Organization (WHO and American Public Health Association (APHA, respectively, while values obtained for ammonium nitrogen in these water samples calls for serious checks on methods of their production and delivery to the end users.

  13. Culture of microalgae biomass for valorization of table olive processing water

    Directory of Open Access Journals (Sweden)

    Contreras, C. G.

    2016-09-01

    Full Text Available Table olive processing water (TOPW contains many complex substances, such as phenols, which could be valorized as a substrate for microalgae biomass culture. The aim of this study was to assess the capability of Nannochloropsis gaditana to grow in TOPW at different concentrations (10- 80% in order to valorize this processing water. Within this range, the highest increment of biomass was determined at percentage of 40% of TOPW, reaching an increment of 0.36 ± 0.05 mg volatile suspended solids (VSS/L. Components of algal biomass were similar for the experiments at 10-40% of TOPW, where proteins were the major compounds (56-74%. Total phenols were retained in the microalgae biomass (0.020 ± 0.002 g of total phenols/g VSS. Experiments for 80% of TOPW resulted in a low production of microalgae biomass. High organic matter, nitrogen, phosphorus and phenol removal were achieved in all TOPW concentrations. Although high-value products, such as proteins, were obtained and high removal efficiencies of nutrients were determined, microalgae biomass culture should be enhanced to become a suitable integral processing water treatment.El agua resultante del proceso de elaboración de la aceituna de mesa (TOPW presenta un elevado contenido en sustancias complejas, como fenoles, que podría permitir su uso como sustrato para el cultivo de microalgas. El objetivo de este estudio se centra en evaluar la capacidad de crecimiento de Nannochloropsis gaditana en TOPW a distintas concentraciones (10-80% con vistas a la valorización de estas aguas. El mayor incremento de biomasa se obtuvo para un porcentaje del 40% de TOPW, alcanzando un aumento de 0.36 ± 0.50 mg sólidos en suspensión volátiles (SSV/L. Los componentes presentes en la biomasa han sido similares para los experimentos con 10-40% de TOPW, siendo las proteínas los compuestos mayoritarios en todos los casos (56-74%. Los fenoles totales quedaron retenidos en las microalgas, alcanzando una concentraci

  14. Depth dependent microbial carbon use efficiency in the capillary fringe as affected by water table fluctuations in a column incubation experiment

    Science.gov (United States)

    Pronk, G. J.; Mellage, A.; Milojevic, T.; Smeaton, C. M.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Microbial growth and turnover of soil organic carbon (SOC) depend on the availability of electron donors and acceptors. The steep geochemical gradients in the capillary fringe between the saturated and unsaturated zones provide hotspots of soil microbial activity. Water table fluctuations and the associated drying and wetting cycles within these zones have been observed to lead to enhanced turnover of SOC and adaptation of the local microbial communities. To improve our understanding of SOC degradation under changing moisture conditions, we carried out an automated soil column experiment with integrated of hydro-bio-geophysical monitoring under both constant and oscillating water table conditions. An artificial soil mixture composed of quartz sand, montmorillonite, goethite and humus was used to provide a well-defined system. This material was inoculated with a microbial community extracted from a forested riparian zone. The soils were packed into 6 columns (60 cm length and 7.5 cm inner diameter) to a height of 45 cm; and three replicate columns were incubated under constant water table while another three were saturated and drained monthly. The initial soil development, carbon cycling and microbial community development were then characterized during 10 months of incubation. This system provides an ideal artificial gradient from the saturated to the unsaturated zone to study soil development from initially homogeneous materials and the same microbial community composition under controlled conditions. Depth profiles of SOC and microbial biomass after 329 days of incubation showed a depletion of carbon in the transition drying and wetting zone that was not associated with higher accumulation of microbial biomass, indicating a lower carbon use efficiency of the microbial community established within the water table fluctuation zone. This was supported by a higher ATP to microbial biomass carbon ratio within the same zone. The findings from this study highlight the

  15. Tables of homogeneous equilibrium critical flow parameters for water in SI units

    International Nuclear Information System (INIS)

    Hall, D.G.; Czapary, L.S.

    1980-09-01

    This reference document presents tables and charts containing data calculated using the homogeneous equilibrium critical flow model (HEM). The ranges of stagnation state properties for which data are presented include: pressures from 2 to 22 120kPa, temperatures from 290 to 640 K, and thermodynamic qualities from 0 to 1

  16. A Mathematical View of Water Table Fluctuations in a Shallow Aquifer in Brazil

    NARCIS (Netherlands)

    Neto, Dagmar C.; Chang, Hung K.; van Genuchten, Martinus Th

    Detailed monitoring of the groundwater table can provide important data about both short- and long-term aquifer processes, including information useful for estimating recharge and facilitating groundwater modeling and remediation efforts. In this paper, we presents results of 4years (2002 to 2005)

  17. Water-table and potentiometric-surface altitudes in the upper glacial, Magothy, and Lloyd aquifers of Long Island, New York, April–May 2016

    Science.gov (United States)

    Como, Michael D.; Finkelstein, Jason S.; Rivera, Simonette L.; Monti, Jack; Busciolano, Ronald J.

    2018-06-06

    The U.S. Geological Survey, in cooperation with State and local agencies, systematically collects groundwater data at varying measurement frequencies to monitor the hydrologic conditions on Long Island, New York. Each year during April and May, the U.S. Geological Survey completes a synoptic survey of water levels to define the spatial distribution of the water table and potentiometric surfaces within the three main water-bearing units underlying Long Island—the upper glacial, Magothy, and Lloyd aquifers—and the hydraulically connected Jameco and North Shore aquifers. These data and the maps constructed from them are commonly used in studies of the hydrology of Long Island and are used by water managers and suppliers for aquifer management and planning purposes.Water-level measurements made in 424 monitoring wells (observation and supply wells), 13 streamgages, and 2 lake gages across Long Island during April–May 2016 were used to prepare the maps in this report. Groundwater measurements were made by the wetted-tape or electric-tape method to the nearest hundredth of a foot. Contours of water-table and potentiometric-surface altitudes were created using the groundwater measurements. The water-table contours were interpreted using water-level data collected from 275 observation wells and 1 supply well screened in the upper glacial aquifer and the shallow Magothy aquifer and 13 streamgages and 2 lake gages. The potentiometric-surface contours of the Magothy aquifer were interpreted from measurements at 88 wells (61 observation wells and 27 supply wells) screened in the middle to deep Magothy aquifer and the contiguous and hydraulically connected Jameco aquifer. The potentiometric-surface contours of the Lloyd aquifer were interpreted from measurements at 60 wells (55 observation wells and 5 supply wells) screened in the Lloyd aquifer and the contiguous and hydraulically connected North Shore aquifer. Many of the supply wells are in continuous operation and

  18. Use of well points to determine the thickness and extent of floating product atop the water table

    International Nuclear Information System (INIS)

    Liikala, T.L.; Lewis, R.; Gilmore, T.; Hoffmann, H.

    1994-01-01

    The release of petroleum products to the ground water is a widespread problem. Conventional plume tracking techniques are to drill wells and measure product thickness and extent. In this study, well points were installed to rapidly and inexpensively determine the thickness and extent of floating product atop the water table. Spills and leaks of JP-4 have produced a discrete full layer atop the water table at one site at Eielson Air Force Base near Fairbanks, Alaska. The 0.2- to 1.3-foot-thick layer was identified in two ground water monitoring wells at a depth of approximately 10 feet. The layer is contained within unconsolidated glaciofluvial sands and gravels. A comprehensive assessment of the product thickness and extent was necessary for the site remedial investigation/feasibility study. The emplacement of additional monitoring wells was discouraged because of time and budget constraints. The fuel layer was delineated with 18 screened well points. The points consist of 2-inch-diameter galvanized steel pipe. The points were driven into the floating products with a hollow-stem auger rig sampling hammer. The product thickness was measured with an interface probe. The presence of floating product could be measured immediately after emplacement; the product thickness measurements typically stabilized within three days. The product thickness compared favorably with those measured in adjacent monitoring wells

  19. Developing a Long Short-Term Memory (LSTM) based model for predicting water table depth in agricultural areas

    Science.gov (United States)

    Zhang, Jianfeng; Zhu, Yan; Zhang, Xiaoping; Ye, Ming; Yang, Jinzhong

    2018-06-01

    Predicting water table depth over the long-term in agricultural areas presents great challenges because these areas have complex and heterogeneous hydrogeological characteristics, boundary conditions, and human activities; also, nonlinear interactions occur among these factors. Therefore, a new time series model based on Long Short-Term Memory (LSTM), was developed in this study as an alternative to computationally expensive physical models. The proposed model is composed of an LSTM layer with another fully connected layer on top of it, with a dropout method applied in the first LSTM layer. In this study, the proposed model was applied and evaluated in five sub-areas of Hetao Irrigation District in arid northwestern China using data of 14 years (2000-2013). The proposed model uses monthly water diversion, evaporation, precipitation, temperature, and time as input data to predict water table depth. A simple but effective standardization method was employed to pre-process data to ensure data on the same scale. 14 years of data are separated into two sets: training set (2000-2011) and validation set (2012-2013) in the experiment. As expected, the proposed model achieves higher R2 scores (0.789-0.952) in water table depth prediction, when compared with the results of traditional feed-forward neural network (FFNN), which only reaches relatively low R2 scores (0.004-0.495), proving that the proposed model can preserve and learn previous information well. Furthermore, the validity of the dropout method and the proposed model's architecture are discussed. Through experimentation, the results show that the dropout method can prevent overfitting significantly. In addition, comparisons between the R2 scores of the proposed model and Double-LSTM model (R2 scores range from 0.170 to 0.864), further prove that the proposed model's architecture is reasonable and can contribute to a strong learning ability on time series data. Thus, one can conclude that the proposed model can

  20. Impacts of soil conditioners and water table management on phosphorus loss in tile drainage from a clay loam soil.

    Science.gov (United States)

    Zhang, T Q; Tan, C S; Zheng, Z M; Welacky, T W; Reynolds, W D

    2015-03-01

    Adoption of waste-derived soil conditioners and refined water management can improve soil physical quality and crop productivity of fine-textured soils. However, the impacts of these practices on water quality must be assessed to ensure environmental sustainability. We conducted a study to determine phosphorus (P) loss in tile drainage as affected by two types of soil conditioners (yard waste compost and swine manure compost) and water table management (free drainage and controlled drainage with subirrigation) in a clay loam soil under corn-soybean rotation in a 4-yr period from 1999 to 2003. Tile drainage flows were monitored and sampled on a year-round continuous basis using on-site auto-sampling systems. Water samples were analyzed for dissolved reactive P (DRP), particulate P (PP), and total P (TP). Substantially greater concentrations and losses of DRP, PP, and TP occurred with swine manure compost than with control and yard waste compost regardless of water table management. Compared with free drainage, controlled drainage with subirrigation was an effective way to reduce annual and cumulative losses of DRP, PP, and TP in tile drainage through reductions in flow volume and P concentration with control and yard waste compost but not with swine manure compost. Both DRP and TP concentrations in tile drainage were well above the water quality guideline for P, affirming that subsurface loss of P from fine-textured soils can be one critical source for freshwater eutrophication. Swine manure compost applied as a soil conditioner must be optimized by taking water quality impacts into consideration. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Estimation of groundwater consumption by phreatophytes using diurnal water table fluctuations: A saturated‐unsaturated flow assessment

    Science.gov (United States)

    Loheide, Steven P.; Butler, James J.; Gorelick, Steven M.

    2005-01-01

    Groundwater consumption by phreatophytes is a difficult‐to‐measure but important component of the water budget in many arid and semiarid environments. Over the past 70 years the consumptive use of groundwater by phreatophytes has been estimated using a method that analyzes diurnal trends in hydrographs from wells that are screened across the water table (White, 1932). The reliability of estimates obtained with this approach has never been rigorously evaluated using saturated‐unsaturated flow simulation. We present such an evaluation for common flow geometries and a range of hydraulic properties. Results indicate that the major source of error in the White method is the uncertainty in the estimate of specific yield. Evapotranspirative consumption of groundwater will often be significantly overpredicted with the White method if the effects of drainage time and the depth to the water table on specific yield are ignored. We utilize the concept of readily available specific yield as the basis for estimation of the specific yield value appropriate for use with the White method. Guidelines are defined for estimating readily available specific yield based on sediment texture. Use of these guidelines with the White method should enable the evapotranspirative consumption of groundwater to be more accurately quantified.

  2. Preliminary phenomena identification and ranking tables for simplified boiling water reactor Loss-of-Coolant Accident scenarios

    International Nuclear Information System (INIS)

    Kroeger, P.G.; Rohatgi, U.S.; Jo, J.H.; Slovik, G.C.

    1998-04-01

    For three potential Loss-of-Coolant Accident (LOCA) scenarios in the General Electric Simplified Boiling Water Reactors (SBWR) a set of Phenomena Identification and Ranking Tables (PIRT) is presented. The selected LOCA scenarios are typical for the class of small and large breaks generally considered in Safety Analysis Reports. The method used to develop the PIRTs is described. Following is a discussion of the transient scenarios, the PIRTs are presented and discussed in detailed and in summarized form. A procedure for future validation of the PIRTs, to enhance their value, is outlined. 26 refs., 25 figs., 44 tabs

  3. Estimating the water table under the Radioactive Waste Management Site in Area 5 of the Nevada Test Site: The Dupuit-Forcheimer approximation

    International Nuclear Information System (INIS)

    Lindstrom, F.T.; Barker, L.E.; Cawlfield, D.E.; Daffern, D.D.; Dozier, B.L.; Emer, D.F.; Strong, W.R.

    1992-01-01

    To adequately manage the low level nuclear waste (LLW) repository in Area 5 of the Nevada Test Site (NTS), a knowledge of the water table under the site is paramount. The estimated thickness of the arid intermountain basin alluvium is roughly 900 feet. Very little reliable water table data for Area 5 currently exists. The Special Projects Section of the Reynolds Electrical ampersand Engineering Co., Inc. Waste Management Department is currently formulating a long-range drilling and sampling plan in support of a Resource Conservation Recovery Act (RCRA) Part B permit waiver for groundwater monitoring and liner systems. An estimate of the water table under the LLW repository, called the Radioactive Waste Management Site (RWMS) in Area 5, is needed for the drilling and sampling plan. Very old water table elevation estimates at about a dozen widely scattered test drill holes, as well as water wells, are available from declassified US Geological Survey, Lawrence Livermore National Laboratory, and Los Alamos National Laboratory drilling logs. A three-dimensional steady-state water-flow equation for estimating the water table elevation under a thick, very dry vadose zone is developed using the Dupuit assumption. A prescribed positive vertical downward infiltration/evaporation condition is assumed at the atmosphere/soil interface. An approximation to the square of the elevation head, based upon multivariate cubic interpolation methods, is introduced. The approximate is forced to satisfy the governing elliptic (Poisson) partial differential equation over the domain of definition. The remaining coefficients are determined by interpolating the water table at eight ''boundary point.'' Several realistic scenarios approximating the water table under the RWMS in Area 5 of the NTS are discussed

  4. A technique to circumvent lower density water trapping by tide-wells

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.; VijayKumar, K.; Desa, E.S.; Desa, E.; Peshwe, V.B.

    A 3-year study of water density differences inside and outside of a conventional tide-well indicated that the average water density within the well is consistently lower than the external ambient waters. The tide-well at Goa is situated at the mouth...

  5. Paleohydrology of the southern Great Basin, with special reference to water table fluctuations beneath the Nevada Test Site during the late(?) Pleistocene

    Science.gov (United States)

    Winograd, Isaac Judah; Doty, Gene C.

    1980-01-01

    Knowledge of the magnitude of water-table rise during Pleistocene pluvial climates, and of the resultant shortening of groundwater flow path and reduction in unsaturated zone thickness, is mandatory for a technical evaluation of the Nevada Test Site (NTS) or other arid zone sites as repositories for high-level or transuranic radioactive wastes. The distribution of calcitic veins filling fractures in alluvium, and of tufa deposits between the Ash Meadows spring discharge area and the Nevada Test Site indicates that discharge from the regional Paleozoic carbonate aquifer during the Late( ) Pleistocene pluvial periods may have occurred at an altitude about 50 meters higher than at present and 14 kilometers northeast of Ash Meadows. Use of the underflow equation (relating discharge to transmissivity, aquifer width, and hydraulic gradient), and various assumptions regarding pluvial recharge, transmissivity, and altitude of groundwater base level, suggest possible rises in potentiometric level in the carbonate aquifer of about -90 meters beneath central Frenchman Flat. During Wisconsin time the rise probably did not exceed 30 meters. Water-level rises beneath Frenchman Flat during future pluvials are unlikely to exceed 30 meters and might even be 10 meters lower than modern levels. Neither the cited rise in potentiometric level in the regional carbonate aquifer, nor the shortened flow path during the Late( ) Pleistocene preclude utilization of the NTS as a repository for high-level or transuranic-element radioactive wastes provided other requisite conditions are met as this site. Deep water tables, attendant thick (up to several hundred meter) unsaturated zones, and long groundwater flow paths characterized the region during the Wisconsin Stage and probably throughout the Pleistocene Epoch and are likely to so characterize it during future glacial periods. (USGS)

  6. Groundwater in the Boreal Plains: How Climate and Geology Interact to Control Water Table Configurations in a Sub-Humid, Low-Relief Region

    Science.gov (United States)

    Hokanson, K. J.; Devito, K.; Mendoza, C. A.

    2017-12-01

    The Boreal Plain (BP) region of Canada, a landscape characterized by low-relief, a sub-humid climate and heterogeneous glacial landforms, is experiencing unprecedented anthropogenic and natural disturbance, including climate change and oil & gas operations. Understanding the controls on and the natural variability of water table position, and subsequently predicting changes in water table position under varying physical and climatic scenarios will become important as water security becomes increasingly threatened. The BP is composed of a mosaic of forestland, wetland, and aquatic land covers that contrast in dominant vegetation cover, evapotranspiration, and soil storage that, in turn, influence water table configurations. Additionally, these land-covers overlie heterogeneous glacial landforms with large contrasts in storage and hydraulic properties which, when coupled with wet-dry climate cycles, result in complex water table distributions in time and space. Several forestland-wetland-pond complexes were selected at the Utikuma Research Study Area (URSA) over three distinct surficial geologic materials (glacial fluvial outwash, stagnant ice moraine, lacustrine clay plain) to explore the roles of climate (cumulative departure from the long term yearly mean precipitation), geology, topographic position, and land cover on water table configurations over 15 years (2002 - 2016). In the absence of large groundwater flow systems, local relief and shallow low conductivity substrates promote the formation of near-surface water tables that are less susceptible to climate variation, regardless of topography. Furthermore, in areas of increased storage, wet and dry climate conditions can result in appreciably different water table configurations over time, ranging from mounds to hydraulic depressions, depending on the arrangement of land-covers, dominant surficial geology, and substrate layering.

  7. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips - Part 1: nonuniform infiltration and soil water redistribution

    Science.gov (United States)

    Muñoz-Carpena, Rafael; Lauvernet, Claire; Carluer, Nadia

    2018-01-01

    Vegetation buffers like vegetative filter strips (VFSs) are often used to protect water bodies from surface runoff pollution from disturbed areas. Their typical placement in floodplains often results in the presence of a seasonal shallow water table (WT) that can decrease soil infiltration and increase surface pollutant transport during a rainfall-runoff event. Simple and robust components of hydrological models are needed to analyze the impacts of WT in the landscape. To simulate VFS infiltration under realistic rainfall conditions with WT, we propose a generic infiltration solution (Shallow Water table INfiltration algorithm: SWINGO) based on a combination of approaches by Salvucci and Entekhabi (1995) and Chu (1997) with new integral formulae to calculate singular times (time of ponding, shift time, and time to soil profile saturation). The algorithm was tested successfully on five distinct soils, both against Richards's numerical solution and experimental data in terms of infiltration and soil moisture redistribution predictions, and applied to study the combined effects of varying WT depth, soil type, and rainfall intensity and duration. The results show the robustness of the algorithm and its ability to handle various soil hydraulic functions and initial nonponding conditions under unsteady rainfall. The effect of a WT on infiltration under ponded conditions was found to be effectively decoupled from surface infiltration and excess runoff processes for depths larger than 1.2 to 2 m, being shallower for fine soils and shorter events. For nonponded initial conditions, the influence of WT depth also varies with rainfall intensity. Also, we observed that soils with a marked air entry (bubbling pressure) exhibit a distinct behavior with WT near the surface. The good performance, robustness, and flexibility of SWINGO supports its broader use to study WT effects on surface runoff, infiltration, flooding, transport, ecological, and land use processes. SWINGO is

  8. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 1: nonuniform infiltration and soil water redistribution

    Directory of Open Access Journals (Sweden)

    R. Muñoz-Carpena

    2018-01-01

    Full Text Available Vegetation buffers like vegetative filter strips (VFSs are often used to protect water bodies from surface runoff pollution from disturbed areas. Their typical placement in floodplains often results in the presence of a seasonal shallow water table (WT that can decrease soil infiltration and increase surface pollutant transport during a rainfall-runoff event. Simple and robust components of hydrological models are needed to analyze the impacts of WT in the landscape. To simulate VFS infiltration under realistic rainfall conditions with WT, we propose a generic infiltration solution (Shallow Water table INfiltration algorithm: SWINGO based on a combination of approaches by Salvucci and Entekhabi (1995 and Chu (1997 with new integral formulae to calculate singular times (time of ponding, shift time, and time to soil profile saturation. The algorithm was tested successfully on five distinct soils, both against Richards's numerical solution and experimental data in terms of infiltration and soil moisture redistribution predictions, and applied to study the combined effects of varying WT depth, soil type, and rainfall intensity and duration. The results show the robustness of the algorithm and its ability to handle various soil hydraulic functions and initial nonponding conditions under unsteady rainfall. The effect of a WT on infiltration under ponded conditions was found to be effectively decoupled from surface infiltration and excess runoff processes for depths larger than 1.2 to 2 m, being shallower for fine soils and shorter events. For nonponded initial conditions, the influence of WT depth also varies with rainfall intensity. Also, we observed that soils with a marked air entry (bubbling pressure exhibit a distinct behavior with WT near the surface. The good performance, robustness, and flexibility of SWINGO supports its broader use to study WT effects on surface runoff, infiltration, flooding, transport, ecological, and land use processes

  9. Spatial variation of nitrogen pollution of the water table at Oued M'Zab (Northern Algerian Sahara)

    Science.gov (United States)

    Benhedid, H.; Bouhoun, M. Daddi

    2018-05-01

    The aim of our work is the study of spatial variations of the water table pollution of Oued M'Zab, in order to determine their abilities of use and the posed problems of degradation. The methodological approach we adopted is to make a spatial study of the variability of nitrogen pollution, as well as to classify water quality according to international standards. The main results obtained in this research show that NH4+ range from 0 to 0,143 mg.l-1 with an average of 0,048 ± 0,039 mg.l-1, the NO2- from 0 to 0,209 mg.l-1 give an average of 0,007 ± 0,033 mg.l-1, and the NO3- vary between 14,264 and 143,465 mg.l-1, with a mean value 54,594 ± 30,503 mg.l-1. According to W.H.O. standards, the majority of these waters are classified as polluted and not drinkable. Our research shows a degradation of the underground water resources in M'Zab Valley. It resulted that it is essential to regulate the use of water and set out other adjustments in order to safeguard the underground water resources so as to promote sustainable development in the valley of M'Zab.

  10. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips - Part 2: model coupling, application, factor importance, and uncertainty

    Science.gov (United States)

    Lauvernet, Claire; Muñoz-Carpena, Rafael

    2018-01-01

    Vegetative filter strips are often used for protecting surface waters from pollution transferred by surface runoff in agricultural watersheds. In Europe, they are often prescribed along the stream banks, where a seasonal shallow water table (WT) could decrease the buffer zone efficiency. In spite of this potentially important effect, there are no systematic experimental or theoretical studies on the effect of this soil boundary condition on the VFS efficiency. In the companion paper (Muñoz-Carpena et al., 2018), we developed a physically based numerical algorithm (SWINGO) that allows the representation of soil infiltration with a shallow water table. Here we present the dynamic coupling of SWINGO with VFSMOD, an overland flow and transport mathematical model to study the WT influence on VFS efficiency in terms of reductions of overland flow, sediment, and pesticide transport. This new version of VFSMOD was applied to two contrasted benchmark field studies in France (sandy-loam soil in a Mediterranean semicontinental climate, and silty clay in a temperate oceanic climate), where limited testing of the model with field data on one of the sites showed promising results. The application showed that for the conditions of the studies, VFS efficiency decreases markedly when the water table is 0 to 1.5 m from the surface. In order to evaluate the relative importance of WT among other input factors controlling VFS efficiency, global sensitivity and uncertainty analysis (GSA) was applied on the benchmark studies. The most important factors found for VFS overland flow reduction were saturated hydraulic conductivity and WT depth, added to sediment characteristics and VFS dimensions for sediment and pesticide reductions. The relative importance of WT varied as a function of soil type (most important at the silty-clay soil) and hydraulic loading (rainfall + incoming runoff) at each site. The presence of WT introduced more complex responses dominated by strong interactions in

  11. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips – Part 2: model coupling, application, factor importance, and uncertainty

    Directory of Open Access Journals (Sweden)

    C. Lauvernet

    2018-01-01

    Full Text Available Vegetative filter strips are often used for protecting surface waters from pollution transferred by surface runoff in agricultural watersheds. In Europe, they are often prescribed along the stream banks, where a seasonal shallow water table (WT could decrease the buffer zone efficiency. In spite of this potentially important effect, there are no systematic experimental or theoretical studies on the effect of this soil boundary condition on the VFS efficiency. In the companion paper (Muñoz-Carpena et al., 2018, we developed a physically based numerical algorithm (SWINGO that allows the representation of soil infiltration with a shallow water table. Here we present the dynamic coupling of SWINGO with VFSMOD, an overland flow and transport mathematical model to study the WT influence on VFS efficiency in terms of reductions of overland flow, sediment, and pesticide transport. This new version of VFSMOD was applied to two contrasted benchmark field studies in France (sandy-loam soil in a Mediterranean semicontinental climate, and silty clay in a temperate oceanic climate, where limited testing of the model with field data on one of the sites showed promising results. The application showed that for the conditions of the studies, VFS efficiency decreases markedly when the water table is 0 to 1.5 m from the surface. In order to evaluate the relative importance of WT among other input factors controlling VFS efficiency, global sensitivity and uncertainty analysis (GSA was applied on the benchmark studies. The most important factors found for VFS overland flow reduction were saturated hydraulic conductivity and WT depth, added to sediment characteristics and VFS dimensions for sediment and pesticide reductions. The relative importance of WT varied as a function of soil type (most important at the silty-clay soil and hydraulic loading (rainfall + incoming runoff at each site. The presence of WT introduced more complex responses dominated by strong

  12. Distribution of fallout plutonium in the waters of the lower Great Lakes

    International Nuclear Information System (INIS)

    Alberts, J.J.; Wahlgren, M.A.; Nelson, D.M.

    1976-01-01

    The concentrations of fallout 239 240 Pu in the surface waters from all the Great Lakes were slightly lower in 1976 samples than in those from 1973. The same trend of higher concentrations in the surface waters of the upper lakes as in the surface waters of the lower lakes was observed for both years. In addition, the 239 240 Pu concentration in samples of deep water collected during the summer of 1976 was higher than in the surface waters but was similar to the surface water values of the 1973 spring samples. This observation is significant in that it suggests that the surface waters of all the Great Lakes undergo a seasonal decrease in plutonium concentration similar to that already observed in Lake Michigan

  13. Relation between Nitrates in Water Wells and Potential Sources in the Lower Yakima Valley, Washington State

    Science.gov (United States)

    Results of a study EPA conducted to investigate the contribution of various sources to the high nitrate levels in groundwater and residential drinking water wells in the Lower Yakima Valley of Washington State.

  14. Estimating the water table under the Radioactive Waste Management Site in Area 5 of the Nevada Test Site the Dupuit-Forcheimer approximation

    International Nuclear Information System (INIS)

    Lindstrom, T.F.; Barker, L.E.; Cawlfield, D.E.; Daffern, D.D.; Dozier, B.L.; Emer, D.F.; Strong, W.R.

    1992-01-01

    A two-dimensional steady-state water-flow equation for estimating the water table elevation under a thick, very dry vadose zone is developed and discussed. The Dupuit assumption is made. A prescribed downward vertical infiltration/evaporation condition is assumed at the atmosphere-soil interface. An approximation to the square of the elevation head, based upon multivariate cubic interpolation methods, is introduced. The approximation is forced to satisfy the governing elliptic (Poisson) partial differential equation over the domain of definition. The remaining coefficients are determined by interpolating the water table at eight ''boundary points.'' Several realistic scenarios approximating the water table under the Radioactive Waste Management Site (RWMS) in Area 5 of the Nevada Test Site (NTS) are discussed

  15. Estimation of bare soil evaporation for different depths of water table in the wind-blown sand area of the Ordos Basin, China

    Science.gov (United States)

    Chen, Li; Wang, Wenke; Zhang, Zaiyong; Wang, Zhoufeng; Wang, Qiangmin; Zhao, Ming; Gong, Chengcheng

    2018-04-01

    Soil surface evaporation is a significant component of the hydrological cycle, occurring at the interface between the atmosphere and vadose zone, but it is affected by factors such as groundwater level, soil properties, solar radiation and others. In order to understand the soil evaporation characteristics in arid regions, a field experiment was conducted in the Ordos Basin, central China, and high accuracy sensors of soil moisture, moisture potential and temperature were installed in three field soil profiles with water-table depths (WTDs) of about 0.4, 1.4 and 2.2 m. Soil-surface-evaporation values were estimated by observed data combined with Darcy's law. Results showed that: (1) soil-surface-evaporation rate is linked to moisture content and it is also affected by air temperature. When there is sufficient moisture in the soil profile, soil evaporation increases with rising air temperature. For a WTD larger than the height of capillary rise, the soil evaporation is related to soil moisture content, and when air temperature is above 25 °C, the soil moisture content reduces quickly and the evaporation rate lowers; (2) phreatic water contributes to soil surface evaporation under conditions in which the WTD is within the capillary fringe. This indicates that phreatic water would not participate in soil evaporation for a WTD larger than the height of capillary rise. This finding developed further the understanding of phreatic evaporation, and this study provides valuable information on recognized soil evaporation processes in the arid environment.

  16. Impacts of reforestation upon sediment load and water outflow in the Lower Yazoo River Watershed, Mississippi

    Science.gov (United States)

    Ying Ouyang; Theodor D. Leininger; Matt Moran

    2013-01-01

    Among the world’s largest coastal and river basins, the Lower Mississippi River Alluvial Valley (LMRAV)is one of the most disturbed by human activities. This study ascertained the impacts of reforestation on water outflow attenuation (i.e., water flow out of the watershed outlet) and sediment load reduction in the Lower Yazoo River Watershed (LYRW) within the LMRAV...

  17. Three-dimensional hydrogeological modeling to assess the elevated-water-table technique for controlling acid generation from an abandoned tailings site in Quebec, Canada

    Science.gov (United States)

    Ethier, Marie-Pier; Bussière, Bruno; Broda, Stefan; Aubertin, Michel

    2018-01-01

    The Manitou Mine sulphidic-tailings storage facility No. 2, near Val D'Or, Canada, was reclaimed in 2009 by elevating the water table and applying a monolayer cover made of tailings from nearby Goldex Mine. Previous studies showed that production of acid mine drainage can be controlled by lowering the oxygen flux through Manitou tailings with a water table maintained at the interface between the cover and reactive tailings. Simulations of different scenarios were performed using numerical hydrogeological modeling to evaluate the capacity of the reclamation works to maintain the phreatic surface at this interface. A large-scale numerical model was constructed and calibrated using 3 years of field measurements. This model reproduced the field measurements, including the existence of a western zone on the site where the phreatic level targeted is not always met during the summer. A sensitivity analysis was performed to assess the response of the model to varying saturated hydraulic conductivities, porosities, and grain-size distributions. Higher variations of the hydraulic heads, with respect to the calibrated scenario results, were observed when simulating a looser or coarser cover material. Long-term responses were simulated using: the normal climatic data, data for a normal climate with a 2-month dry spell, and a simplified climate-change case. Environmental quality targets were reached less frequently during summer for the dry spell simulation as well as for the simplified climate-change scenario. This study illustrates how numerical simulations can be used as a key tool to assess the eventual performance of various mine-site reclamation scenarios.

  18. Analysis of Tide and Offshore Storm-Induced Water Table Fluctuations for Structural Characterization of a Coastal Island Aquifer

    Science.gov (United States)

    Trglavcnik, Victoria; Morrow, Dean; Weber, Kela P.; Li, Ling; Robinson, Clare E.

    2018-04-01

    Analysis of water table fluctuations can provide important insight into the hydraulic properties and structure of a coastal aquifer system including the connectivity between the aquifer and ocean. This study presents an improved approach for characterizing a permeable heterogeneous coastal aquifer system through analysis of the propagation of the tidal signal, as well as offshore storm pulse signals through a coastal aquifer. Offshore storms produce high wave activity, but are not necessarily linked to significant onshore precipitation. In this study, we focused on offshore storm events during which no onshore precipitation occurred. Extensive groundwater level data collected on a sand barrier island (Sable Island, NS, Canada) show nonuniform discontinuous propagation of the tide and offshore storm pulse signals through the aquifer with isolated inland areas showing enhanced response to both oceanic forcing signals. Propagation analysis suggests that isolated inland water table fluctuations may be caused by localized leakage from a confined aquifer that is connected to the ocean offshore but within the wave setup zone. Two-dimensional groundwater flow simulations were conducted to test the leaky confined-unconfined aquifer conceptualization and to identify the effect of key parameters on tidal signal propagation in leaky confined-unconfined coastal aquifers. This study illustrates that analysis of offshore storm signal propagation, in addition to tidal signal propagation, provides a valuable and low resource approach for large-scale characterization of permeable heterogeneous coastal aquifers. Such an approach is needed for the effective management of coastal environments where water resources are threatened by human activities and the changing climate.

  19. Evaporation from bare ground with different water-table depths based on an in-situ experiment in Ordos Plateau, China

    Science.gov (United States)

    Zhang, Zaiyong; Wang, Wenke; Wang, Zhoufeng; Chen, Li; Gong, Chengcheng

    2018-03-01

    The dynamic processes of ground evaporation are complex and are related to a multitude of factors such as meteorological influences, water-table depth, and materials in the unsaturated zone. To investigate ground evaporation from a homogeneous unsaturated zone, an in-situ experiment was conducted in Ordos Plateau of China. Two water-table depths were chosen to explore the water movement in the unsaturated zone and ground evaporation. Based on the experimental and calculated results, it was revealed that (1) bare ground evaporation is an atmospheric-limited stage for the case of water-table depth being close to the capillary height; (2) the bare ground evaporation is a water-storage-limited stage for the case of water-table depth being beyond the capillary height; (3) groundwater has little effect on ground-surface evaporation when the water depth is larger than the capillary height; and (4) ground evaporation is greater at nighttime than that during the daytime; and (5) a liquid-vapor interaction zone at nearly 20 cm depth is found, in which there exists a downward vapor flux on sunny days, leading to an increasing trend of soil moisture between 09:00 to 17:00; the maximum value is reached at midday. The results of this investigation are useful to further understand the dynamic processes of ground evaporation in arid areas.

  20. Functional roles of lower-limb joint moments while walking in water.

    Science.gov (United States)

    Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami

    2005-02-01

    To clarify the functional roles of lower-limb joint moments and their contribution to support and propulsion tasks while walking in water compared with that on land. Sixteen healthy, young subjects walked on land and in water at several different speeds with and without additional loads. Walking in water is a major rehabilitation therapy for patients with orthopedic disorders. However, the functional role of lower-limb joint moments while walking in water is still unclear. Kinematics, electromyographic activities in biceps femoris and gluteus maximums, and ground reaction forces were measured under the following conditions: walking on land and in water at a self-determined pace, slow walking on land, and fast walking in water with or without additional loads (8 kg). The hip, knee, and ankle joint moments were calculated by inverse dynamics. The contribution of the walking speed increased the hip extension moment, and the additional weight increased the ankle plantar flexion and knee extension moment. The major functional role was different in each lower-limb joint muscle. That of the muscle group in the ankle is to support the body against gravity, and that of the muscle group involved in hip extension is to contribute to propulsion. In addition, walking in water not only reduced the joint moments but also completely changed the inter-joint coordination. It is of value for clinicians to be aware that the greater the viscosity of water produces a greater load on the hip joint when fast walking in water.

  1. CARACTERISTICS OF THE LOWER DANUBE WATER BODIES BETWEEN PORTILE DE FIER

    Directory of Open Access Journals (Sweden)

    Elena ŢUCHIU

    2010-12-01

    Full Text Available The main goal of the Water Framework Directive (2000/60/EC Directive is the achievement of the “good status” of the water bodies, environmental objective which can be reached through elaboration and implementation of the River Basin Management Plan. According to the legal requirements, at the 22nd of December 2009, Romania has elaborated the first National Management Plan – synthesis of the River Basin Management Plans. This process assumes the types identification and water bodies delineation on the basis of some abiotic and biotic parameters, such: water category, abiotic and biotic typology, physical features, water status, pressures and their impacts, as well as protected areas. Therefore, for the lower Danube sector between Bazias and Isaccea 4 water bodies have been delineated: 2 reservoirs (Portile de Fier/Iron Gates and Ostrov and 2 river sectors (Ostrov – Chiciu, Chiciu – Isaccea. The procedure for assessment of the environmental objectives risk failing (on the basis of pressures and impacts has shown that all 4 water bodies have been identified at risk from the point of view of organic substances, nutrients, hazardous substances and hydro-morphological alterations. The Water Framework Directive defines the surface water status through: the ecological status - 5 classes (based on biological, hydro-morphological and physic-chemical elements and chemical status – 2 classes (based on priority substances. In present, the 4 water bodies identified on the lower Danube sector do not reach the good status, being designated as heavily modified water bodies.

  2. Effect of agroforestry system on yield attributes of wheat (Triticum Aestivum l.) under shallow water table conditions

    International Nuclear Information System (INIS)

    Kiran, R.; Agnihotri, A.K.

    2001-01-01

    Fifteen tree rows of Eucalyptus tereticornis were planted at G.B.Pant University of Agriculture and Technology, Pant Nagar, located in tarai region of Uttaranchal in a Nelder fan design in March 1989 at the angle of 24øN' from each other starting from north in anticlockwise direction. Area per tree was 30 m 2 . Wheat was intercropped with Eucalyptus tereticornis of 21st November, 1996. Each row of trees was one treatment. There were 15 treatments with control as sole crop. Various yield attributes, net radiation and water table depth were measured below trees and in control, simultaneously. In treatments 7, 8, 9, 10 and 12 early vegetative growth was observed below trees. Higher yield attributing characters were also observed in some of the treatments below trees. In general, treatment 9 (192-216ø) gave better yield attributes than that of control

  3. Creation of Soil Water and Physical data base and its inclusion in a new version of GIS of Soil Resources Attributive Table

    International Nuclear Information System (INIS)

    Kolev, Boyko

    2013-01-01

    For better using of GIS of Soil Resources a new version of the attributive table formation was created. This makes possible soil, physical, and water properties to be included into the table. The simulation procedure for soil hydro-physical properties determination was realized by using the soil particle size distribution data only. This develops a calculation algorithm for soil water content dynamic monitoring, which was realized for some of Bulgarian soils. The main aims of the study are: To demonstrate the usefulness of the new version of the attributive table formation. To show how the simulation model can be applied for environment conditions monitoring and agricultural production management. Keywords: environment conditions, simulation model, soil moisture at field capacity, wilting point, effective soil water content, particle size distribution

  4. A decade of boreal rich fen greenhouse gas fluxes in response to natural and experimental water table variability

    Science.gov (United States)

    Olefeldt, David; Euskirchen, Eugénie S.; Harden, Jennifer W.; Kane, Evan S.; McGuire, A. David; Waldrop, Mark P.; Turetsky, Merritt R.

    2017-01-01

    Rich fens are common boreal ecosystems with distinct hydrology, biogeochemistry and ecology that influence their carbon (C) balance. We present growing season soil chamber methane emission (FCH4), ecosystem respiration (ER), net ecosystem exchange (NEE) and gross primary production (GPP) fluxes from a 9-years water table manipulation experiment in an Alaskan rich fen. The study included major flood and drought years, where wetting and drying treatments further modified the severity of droughts. Results support previous findings from peatlands that drought causes reduced magnitude of growing season FCH4, GPP and NEE, thus reducing or reversing their C sink function. Experimentally exacerbated droughts further reduced the capacity for the fen to act as a C sink by causing shifts in vegetation and thus reducing magnitude of maximum growing season GPP in subsequent flood years by ~15% compared to control plots. Conversely, water table position had only a weak influence on ER, but dominant contribution to ER switched from autotrophic respiration in wet years to heterotrophic in dry years. Droughts did not cause inter-annual lag effects on ER in this rich fen, as has been observed in several nutrient-poor peatlands. While ER was dependent on soil temperatures at 2 cm depth, FCH4 was linked to soil temperatures at 25 cm. Inter-annual variability of deep soil temperatures was in turn dependent on wetness rather than air temperature, and higher FCH4 in flooded years was thus equally due to increased methane production at depth and decreased methane oxidation near the surface. Short-term fluctuations in wetness caused significant lag effects on FCH4, but droughts caused no inter-annual lag effects on FCH4. Our results show that frequency and severity of droughts and floods can have characteristic effects on the exchange of greenhouse gases, and emphasize the need to project future hydrological regimes in rich fens.

  5. Gas exchange patterns and water loss rates in the Table Mountain cockroach, Aptera fusca (Blattodea: Blaberidae).

    Science.gov (United States)

    Groenewald, Berlizé; Bazelet, Corinna S; Potter, C Paige; Terblanche, John S

    2013-10-15

    The importance of metabolic rate and/or spiracle modulation for saving respiratory water is contentious. One major explanation for gas exchange pattern variation in terrestrial insects is to effect a respiratory water loss (RWL) saving. To test this, we measured the rates of CO2 and H2O release ( and , respectively) in a previously unstudied, mesic cockroach, Aptera fusca, and compared gas exchange and water loss parameters among the major gas exchange patterns (continuous, cyclic, discontinuous gas exchange) at a range of temperatures. Mean , and per unit did not differ among the gas exchange patterns at all temperatures (P>0.09). There was no significant association between temperature and gas exchange pattern type (P=0.63). Percentage of RWL (relative to total water loss) was typically low (9.79±1.84%) and did not differ significantly among gas exchange patterns at 15°C (P=0.26). The method of estimation had a large impact on the percentage of RWL, and of the three techniques investigated (traditional, regression and hyperoxic switch), the traditional method generally performed best. In many respects, A. fusca has typical gas exchange for what might be expected from other insects studied to date (e.g. , , RWL and cuticular water loss). However, we found for A. fusca that expressed as a function of metabolic rate was significantly higher than the expected consensus relationship for insects, suggesting it is under considerable pressure to save water. Despite this, we found no consistent evidence supporting the conclusion that transitions in pattern type yield reductions in RWL in this mesic cockroach.

  6. Methane transport and emissions from soil as affected by water table and vascular plants

    OpenAIRE

    Bhullar, Gurbir S; Iravani, Majid; Edwards, Peter J; Olde Venterink, Harry

    2013-01-01

    Background: The important greenhouse gas (GHG) methane is produced naturally in anaerobic wetland soils. By affecting the production, oxidation and transport of methane to the atmosphere, plants have a major influence upon the quantities emitted by wetlands. Different species and functional plant groups have been shown to affect these processes differently, but our knowledge about how these effects are influenced by abiotic factors such as water regime and temperature remains limited. Here...

  7. SIMULATION OF THE BEHAVIOR OF THE WATER TABLE IN A COASTAL AQUIFER SYSTEM FINITE ELEMENT

    Directory of Open Access Journals (Sweden)

    Luis Lara Romero

    2016-06-01

    Full Text Available This paper presents the application of Galerkin method to discretize the model equation of groundwater ow in a conned aquifer semipermeable with tidal boundary conditions on one of its borders, the other borders remain constant. For the simulations was generated a numerical program, Ground Water Finite Element Method, which implements the method of nite elements with triangular elements with three nodes and a degree of freedom per node.

  8. Surface water-quality assessment of the lower Kansas River basin, Kansas and Nebraska; project description

    Science.gov (United States)

    Stamer, J.K.; Jordan, P.R.; Engberg, R.A.; Dugan, J.T.

    1987-01-01

    In 1986 the U.S. Geological Survey began a National Water-Quality Assessment Program to: (1) provide nationally consistent descriptions of the current status of water quality for a large, diverse, and geographically distributed part of the Nation 's surface water resources; (2) where possible, define trends in water quality; and (3) identify and describe the relation between water quality and natural and land use factors. This report describes the pilot study of the lower Kansas River basin, which is one of four surface water pilot studies that will be used to test, and modify as necessary, assessment concepts and approaches in preparation for future full implementation of the national program. Water quality issues in the lower Kansas River basin are dominated by possible nonpoint sources of contamination from agricultural land, with issues including: (1) large sediment discharge in the streams and sediment deposition in the reservoirs caused by intensive cultivation of row crops and subsequent erosion; (2) occurrence of pesticides in streams and reservoirs that could impair the suitability of water for aquatic life and has the potential for impairing the water 's suitability for public supply; (3) bacterial contamination caused by runoff from pastureland and feedlot operations and municipal wastewater discharges; and (4) nutrient enrichment of reservoirs. Data from fixed stations will be used to determine frequency distributions of constituent concentrations and mass balances of constituents between stations. Subbasin or river reach studies will provide a better understanding of the origin, movement, and fate of potential contaminants. (Lantz-PTT)

  9. Environmental Monitoring, Water Quality - MO 2009 Water Quality Standards - Table G Lake Classifications and Use Designations (SHP)

    Data.gov (United States)

    NSGIC State | GIS Inventory — This data set contains Missouri Water Quality Standards (WQS) lake classifications and use designations described in the Missouri Code of State Regulations (CSR), 10...

  10. Effect of the spatial distribution of physical aquifer properties on modelled water table depth and stream discharge in a headwater catchment

    Directory of Open Access Journals (Sweden)

    C. Gascuel-Odoux

    2010-07-01

    Full Text Available Water table depth and its dynamics on hillslopes are often poorly predicted despite they control both water transit time within the catchment and solute fluxes at the catchment outlet. This paper analyses how relaxing the assumption of lateral homogeneity of physical properties can improve simulations of water table depth and dynamics. Four different spatial models relating hydraulic conductivity to topography have been tested: a simple linear relationship, a linear relationship with two different topographic indexes, two Ks domains with a transitional area. The Hill-Vi model has been modified to test these hypotheses. The studied catchment (Kervidy-Naizin, Western France is underlain by schist crystalline bedrock. A shallow and perennial groundwater highly reactive to rainfall events mainly develops in the weathered saprolite layer. The results indicate that (1 discharge and the water table in the riparian zone are similarly predicted by the four models, (2 distinguishing two Ks domains constitutes the best model and slightly improves prediction of the water table upslope, and (3 including spatial variations in the other parameters such as porosity or rate of hydraulic conductivity decrease with depth does not improve the results. These results underline the necessity of better investigations of upslope areas in hillslope hydrology.

  11. Water Table Management Reduces Tile Nitrate Loss in Continuous Corn and in a Soybean-Corn Rotation

    Directory of Open Access Journals (Sweden)

    Craig F. Drury

    2001-01-01

    Full Text Available Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR system was compared over 8 years (1991 to 1999 to a controlled tile drainage/subirrigation (CDS system on a low-slope (0.05 to 0.1% Brookston clay loam soil (Typic Argiaquoll in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994, continuous corn (Zea mays, L. was grown with annual nitrogen (N fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999, a soybean (Glycine max L., Merr.-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l–1 under DR (11.4 mg N l–1, but not under CDS (7.0 mg N l–1. In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l–1 and CDS (4.0 mg N l–1. During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge

  12. Dynamic behaviour of bubbles of water vapour at a temperature lower than the boiling temperature

    International Nuclear Information System (INIS)

    Jansen, Franz

    1966-01-01

    This research thesis reports the study of the theoretical movement of the wall of vapour water bubbles in a sub-saturated boiling regime, i.e. with an average water temperature lower than the boiling temperature. While assuming that bubbles have an initial translational speed at the beginning of their condensation, the author shows that their shrinkage should result in an accelerated displacement in a direction normal to the wall and inward the liquid. Layers of hot water initially close to the wall would therefore be quickly transported towards cold water areas. Experiments allowed, in some cases, the acceleration of bubbles during their condensation to be noticed: for low sub-saturations in still water and for high sub-saturations in water in forced convection, even though, in this last case, the determination of accelerations is more delicate [fr

  13. Fractal water quality fluctuations spanning the periodic table in an intensively farmed watershed.

    Science.gov (United States)

    Aubert, Alice H; Kirchner, James W; Gascuel-Odoux, Chantal; Faucheux, Mikael; Gruau, Gérard; Mérot, Philippe

    2014-01-21

    Recently developed measurement technologies can monitor surface water quality almost continuously, creating high-frequency multiparameter time series and raising the question of how best to extract insights from such rich data sets. Here we use spectral analysis to characterize the variability of water quality at the AgrHys observatory (Western France) over time scales ranging from 20 min to 12 years. Three years of daily sampling at the intensively farmed Kervidy-Naizin watershed reveal universal 1/f scaling for all 36 solutes, yielding spectral slopes of 1.05 ± 0.11 (mean ± standard deviation). These 36 solute concentrations show varying degrees of annual cycling, suggesting different controls on watershed export processes. Twelve years of daily samples of SO4, NO3, and dissolved organic carbon (DOC) show that 1/f scaling does not continue at frequencies below 1/year in those constituents, whereas a 12-year daily record of Cl shows a general 1/f trend down to the lowest measurable frequencies. Conversely, approximately 12 months of 20 min NO3 and DOC measurements show that at frequencies higher than 1/day, the spectra of these solutes steepen to slopes of roughly 3, and at time scales shorter than 2-3 h, the spectra flatten to slopes near zero, reflecting analytical noise. These results confirm and extend the recent discovery of universal fractal 1/f scaling in water quality at the relatively pristine Plynlimon watershed in Wales, further demonstrating the importance of advective-dispersive transport mixing in catchments. However, the steeper scaling at subdaily time scales suggests additional short-term damping of solute concentrations, potentially due to in-stream or riparian processes.

  14. BOREAS TGB-1/TGB-3 Water Table and Peat Temperature Data over the NSA

    Science.gov (United States)

    Bubier, Jill L.; Comer, Neil; Moore, Tim R.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-1 and TGB-3 teams collected several data sets that contributed to understanding the measured trace gas fluxes over sites in the NSA. This data set contains continuous and manual measurements of water level and air and soil temperatures at the four subsites within the NSA Tower Fen site complex. The measurements were taken to understand the thermal and hydrological gradients associated with each plant community present in the fen. Measurements were taken from May to September 1994 and May to October 1996. The data are provided in tabular ASCII files.

  15. Effect of infiltrated water on rheology of plagioclase feldspar under lower crustal condition

    Science.gov (United States)

    Kido, M.; Muto, J.; Koizumi, S.; Nagahama, H.

    2016-12-01

    Fluids in the deep crust have an important role in deformation of lithosphere and seismicity. In this study, we performed deformation experiments to reveal rheological properties of plagioclase feldspars as a main constituent of crustal materials with infilitrated water. Axial compression tests on synthetic polycrystalline anorthite (An) were performed in a Griggs-type deformation apparatus at temparature of 900 °C, strain rates of roughly about 10-5 s-1 and various confining pressures of 0.8-1.4 GPa. Distilled water was added on samples before tests. Times for infiltration of water into samples were changed to investigate the variation of strength associated with diffusion of water. Strengths of wet An tended to decrease with infiltration time or strain magnitude. If other conditions such as temperature, time and strain being the same, strengths increase with confining pressures. Recovered samples show that deformation was concentrated in the lower part of samples. Differential stresses were significantly lower than predicted values by a previous flow law for wet An obtained by low pressure gas apparatus ( 0.4 GPa, Rybacki et al., 2006). This implies that the effect of water on mechanical behavior in higher pressure might be larger than those predicted by lower pressure experiments. Ideal water concentration and strength profile of internal of samples were estimated by one-dimensional model of grain boundary diffusion. Estimated strength of internal part of samples was significant higher than measured stresses. There is possibility that cataclastic flow partially occurred in samples. In addition, deformation-enhanced fluid flow probably occurred. In conclusion, strength of wet An depends on water infiltration time, strain magnitude and confining pressure. The results suggest that the strength of fluid-rich regions in the lower crust becomes lower than that predicted by previous studies.

  16. Performance of methods for estimation of table beet water requirement in Alagoas

    Directory of Open Access Journals (Sweden)

    Daniella P. dos Santos

    Full Text Available ABSTRACT Optimization of water use in agriculture is fundamental, particularly in regions where water scarcity is intense, requiring the adoption of technologies that promote increased irrigation efficiency. The objective of this study was to evaluate evapotranspiration models and to estimate the crop coefficients of beet grown in a drainage lysimeter in the Agreste region of Alagoas. The experiment was conducted at the Campus of the Federal University of Alagoas - UFAL, in the municipality of Arapiraca, AL, between March and April 2014. Crop evapotranspiration (ETc was estimated in drainage lysimeters and reference evapotranspiration (ETo by Penman-Monteith-FAO 56 and Hargreaves-Samani methods. The Hargreaves-Samani method presented a good performance index for ETo estimation compared with the Penman-Monteith-FAO method, indicating that it is adequate for the study area. Beet ETc showed a cumulative demand of 202.11 mm for a cumulative reference evapotranspiration of 152.00 mm. Kc values determined using the Penman-Monteith-FAO 56 and Hargreaves-Samani methods were overestimated, in comparison to the Kc values of the FAO-56 standard method. With the obtained results, it is possible to correct the equations of the methods for the region, allowing for adequate irrigation management.

  17. Long-term Water Table Monitoring of Rio Grande Riparian Ecosystems for Restoration Potential Amid Hydroclimatic Challenges

    Science.gov (United States)

    Thibault, James R.; Cleverly, James R.; Dahm, Clifford N.

    2017-12-01

    Hydrological processes drive the ecological functioning and sustainability of cottonwood-dominated riparian ecosystems in the arid southwestern USA. Snowmelt runoff elevates groundwater levels and inundates floodplains, which promotes cottonwood germination. Once established, these phreatophytes rely on accessible water tables (WTs). In New Mexico's Middle Rio Grande corridor diminished flooding and deepening WTs threaten native riparian communities. We monitored surface flows and riparian WTs for up to 14 years, which revealed that WTs and surface flows, including peak snowmelt discharge, respond to basin climate conditions and resource management. WT hydrographs influence the composition of riparian communities and can be used to assess if potential restoration sites meet native vegetation tolerances for WT depths, rates of recession, and variability throughout their life stages. WTs were highly variable in some sites, which can preclude native vegetation less adapted to deep drawdowns during extended droughts. Rates of WT recession varied between sites and should be assessed in regard to recruitment potential. Locations with relatively shallow WTs and limited variability are likely to be more viable for successful restoration. Suitable sites have diminished greatly as the once meandering Rio Grande has been constrained and depleted. Increasing demands on water and the presence of invasive vegetation better adapted to the altered hydrologic regime further impact native riparian communities. Long-term monitoring over a range of sites and hydroclimatic extremes reveals attributes that can be evaluated for restoration potential.

  18. Streamflow, water quality, and contaminant loads in the lower Charles River Watershed, Massachusetts, 1999-2000

    Science.gov (United States)

    Breault, Robert F.; Sorenson, Jason R.; Weiskel, Peter K.

    2002-01-01

    Streamflow data and dry-weather and stormwater water-quality samples were collected from the main stem of the Charles River upstream of the lower Charles River (or the Basin) and from four partially culverted urban streams that drain tributary subbasins in the lower Charles River Watershed. Samples were collected between June 1999 and September 2000 and analyzed for a number of potential contaminants including nitrate (plus nitrite), ammonia, total Kjeldahl nitrogen, phosphorus, cadmium, chromium, copper, lead, and zinc; and water-quality properties including specific conductance, turbidity, biochemical oxygen demand, fecal coliform bacteria, Entero-coccus bacteria, total dissolved solids, and total suspended sediment. These data were used to identify the major pathways and to determine the magnitudes of contaminants loads that contribute to the poor water quality of the lower Charles River. Water-quality and streamflow data, for one small urban stream and two storm drains that drain subbasins with uniform (greater than 73 percent) land use (including single-family residential, multifamily residential, and commercial), also were collected. These data were used to elucidate relations among streamflow, water quality, and subbasin characteristics. Streamflow in the lower Charles River Watershed can be characterized as being unsettled and flashy. These characteristics result from the impervious character of the land and the complex infrastructure of pipes, pumps, diversionary canals, and detention ponds throughout the watershed. The water quality of the lower Charles River can be considered good?meeting water-quality standards and guidelines?during dry weather. After rainstorms, however, the water quality of the river becomes impaired, as in other urban areas. The poor quality of stormwater and its large quantity, delivered over short periods (hours and days), together with illicit sanitary cross connections, and combined sewer overflows, results in large contaminant

  19. Hydrogeology and water-quality characteristics of the Lower Floridan aquifer in east-central Florida

    Science.gov (United States)

    O'Reilly, Andrew M.; Spechler, Rick M.; McGurk, Brian E.

    2002-01-01

    The hydrogeology and water-quality characteristics of the Lower Floridan aquifer and the relation of the Lower Floridan aquifer to the framework of the Floridan aquifer system were evaluated during a 6-year (1995-2001) study. The study area, a 7,500 square-mile area of east-central Florida, is underlain by three principal hydrogeologic units: the surficial aquifer system, the intermediate confining unit, and the Floridan aquifer system. The Floridan aquifer system, a carbonate-rock aquifer system composed of the Upper Floridan aquifer, a middle semiconfining unit, a middle confining unit, and the Lower Floridan aquifer, is the major source of water supply to east-central Florida. The Upper Floridan aquifer provides much of the water required to meet the current (2002) demand; however, the Lower Floridan aquifer is being used increasingly as a source of freshwater, particularly for municipal needs. For this reason, a better understanding of the aquifer is needed. The Lower Floridan aquifer is present throughout east-central Florida. The aquifer is composed of alternating beds of limestone and dolomite, and is characterized by abundant fractured dolomite zones and solution cavities. The altitude of the top of the Lower Floridan aquifer ranges from less than 600 feet below sea level in the northern part of the study area to more than 1,600 feet below sea level in the southwestern part. Thickness of the unit ranges from about 910 to 1,180 feet. The top of the Lower Floridan aquifer generally is marked by an increase in formation resistivity and by an increase in the occurrence of fractures and solution cavities within the carbonates. Also, a noticeable increase in borehole flow often marks the top of the unit. The bottom of the Lower Floridan aquifer is based on the first occurrence of evaporites. Ground-water in the Lower Floridan aquifer generally moves in a southwest-to-northeast direction across the study area. In September 1998, the altitude of the potentiometric

  20. Soil chemistry and ground-water quality of the water-table zone of the surficial aquifer, Naval Submarine Base Kings Bay, Camden County, Georgia, 1998 and 1999

    Science.gov (United States)

    Leeth, David C.

    2002-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the U.S. Department of the Navy, began an investigation to determine background ground-water quality of the water-table zone of the surficial aquifer and soil chemistry at Naval Submarine Base Kings Bay, Camden County, Georgia, and to compare these data to two abandoned solid- waste disposal areas (referred to by the U.S. Navy as Sites 5 and 16). The quality of water in the water-table zone generally is within the U.S. Environmental Protection Agency (USEPA) drinking-water regulation. The pH of ground water in the study area ranged from 4.0 to 7.6 standard units, with a median value of 5.4. Water from 29 wells is above the pH range and 3 wells are within the range of the USEPA secondary drinking-water regulation (formerly known as the Secondary Maximum Contaminant Level or SMCL) of 6.5 to 8.5 standard units. Also, water from one well at Site 5 had a chloride concentration of 570 milligrams per liter (mg/L,), which is above the USEPA secondary drinking-water regulation of 250 mg/L. Sulfate concentrations in water from two wells at Site 5 are above the USEPA secondary drinking-water regulation of 250 mg/L. Of 22 soil-sampling locations for this study, 4 locations had concentrations above the detection limit for either volatile organic compounds (VOCs), base-neutral acids (BNAs), or pesticides. VOCs detected in the study area include toluene in one background sample; and acetone in one background sample and one sample from Site 16--however, detection of these two compounds may be a laboratory artifact. Pesticides detected in soil at the Submarine Base include two degradates of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT): 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (4,4'-DDD) in one background sample, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (4,4'-DDE) in one background sample and one sample from Site 16; and dibenzofuran in one sample from Site 16. BNAs were detected in one background sample and in two

  1. Polder effects on sediment-to-soil conversion: water table, residual available water capacity, and salt stress interdependence.

    Science.gov (United States)

    Radimy, Raymond Tojo; Dudoignon, Patrick; Hillaireau, Jean Michel; Deboute, Elise

    2013-01-01

    The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields.

  2. Polder Effects on Sediment-to-Soil Conversion: Water Table, Residual Available Water Capacity, and Salt Stress Interdependence

    Directory of Open Access Journals (Sweden)

    Raymond Tojo Radimy

    2013-01-01

    Full Text Available The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields.

  3. Changes in soluble metal concentrations induced by variable water table levels as response to liming and Phragmites australis growth in metal-polluted wetland soils: Management effectiveness

    NARCIS (Netherlands)

    Gonzalez Alcaraz, M.N.; van Gestel, C.A.M.

    2016-01-01

    This study aimed to assess the effectiveness of liming and Phragmites australis growth for the management of metal-polluted wetland soils under fluctuating water table levels. Soil columns (20 cm in diameter and 60 cm high) were constructed with two soil types (pH ~ 6.4 and pH ~ 3.1) and four

  4. Mobility and transport of mercury and methylmercury in peat as a function of changes in water table regime and plant functional groups

    Science.gov (United States)

    Kristine M. Haynes; Evan S. Kane; Lynette Potvin; Erik A. Lilleskov; Randy Kolka; Carl P. J. Mitchell

    2017-01-01

    Climate change is likely to significantly affect the hydrology, ecology, and ecosystem function of peatlands, with potentially important but unclear impacts on mercury mobility within and transport from peatlands. Using a full-factorial mesocosm approach, we investigated the potential impacts on mercury mobility of water table regime changes (high and low) and...

  5. Distortion of calculated whole-body hematocrit during lower-body immersion in water.

    Science.gov (United States)

    Knight, D R; Santoro, T; Bondi, K R

    1986-11-01

    We found a difference between the venous hematocrits of immersed and nonimmersed arms during immersion of the lower body in cold water but not during a comparable exposure to warm water. Fourteen healthy men were exposed to three different experimental conditions: arm immersion, body immersion, and control. The men always sat upright while both upper extremities hung vertically at their sides. During arm immersion, one forearm was completely immersed for 30 min in either cold water (28 degrees C, n = 7) or warm water (38 degrees C, n = 7). This cold-warm water protocol was repeated on separate days for exposure to the remaining conditions of body immersion (immersion of 1 forearm and all tissues below the xiphoid process) and control (no immersion). Blood samples were simultaneously drawn from cannulated veins in both antecubital fossae. Hematocrit difference (Hct diff) was measured by subtracting the nonimmersed forearm's hematocrit (Hct dry) from the immersed forearm's hematocrit (Hct wet). Hct diff was approximately zero when the men were exposed to the control condition and body immersion in warm water. In the remaining conditions, Hct wet dropped below Hct dry (P less than 0.01, 3-way analysis of variance). The decrements of Hct diff showed there were differences between venous hematocrits in immersed and nonimmersed regions of the body, indicating that changes of the whole-body hematocrit cannot be calculated from a large-vessel hematocrit soon after immersing the lower body in cold water.

  6. Spatial risk modelling for water shortage and nitrate pollution in the lower Jordan valley

    International Nuclear Information System (INIS)

    Loibl, W.; Orthofer, R.

    2002-02-01

    This report summarizes the results of the spatial risk modeling activities (work package WP-4.4, 'GIS Risk Modeling') of the INCO-DC project 'Developing Sustainable Water Management in the Jordan Valley'. The project was funded by European Commission's INCO-DC research program. The main objective of the project was to develop the scientific basis for an integral management plan of water resources and their use in the Lower Jordan Valley. The outputs of the project were expected to allow a better understanding of the water management situation, and to provide a sound basis for a better future water management - not only separately in the three countries, but in the overall valley region. The risk modeling was done by the ARCS Seibersdorf research (ARCS), based on information and data provided by the regional partners from Israel (Hebrew University, Jerusalem, HUJ), Palestine (Applied Research Institute, Jerusalem, Bethlehem, ARIJ) and Jordan (EnviroConsult Office, Amman, ECO). The land use classification has been established through a cooperation between ARCS and the Yale University Center for Earth Observation (YUCEO). As a result of the work, the spatial patterns of agricultural and domestic water demand in the Lower Jordan Valley were established, and the spatial dimension of driving forces for water usage and water supply was analyzed. Furthermore, a conceptual model for nitrate leakage (established by HUJ) was translated into a GIS system, and the risks for nitrate pollution of groundwater were quantified. (author)

  7. Storm water control plan for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This document provides the Environmental Restoration Program with information about the erosion and sediment control, storm water management, maintenance, and reporting and record keeping practices to be employed during Phase II of the remediation project for the Lower East Fork Poplar Creek (LEFPC) Operable Unit

  8. Water table and species identity outweigh carbon and nitrogen availability in a softwater plant community

    Science.gov (United States)

    Vanderhaeghe, Floris; Smolders, Alfons J. P.; Roelofs, Jan G. M.; Hoffmann, Maurice

    2013-02-01

    Performance of aquatic macrophytes is driven by many environmental factors, and a major challenge is to understand how aquatic macrophyte communities are structured in various environments. In softwater lakes in Western Europe, hydrological state (submersed/emersed), carbon dioxide and ammonium levels and species interactions are considered as driving forces in structuring amphibious plant communities. In this study we aimed at evaluating the relative importance of these factors for four species in a competitive neighbourhood. Softwater lake habitat was simulated during one growing season in laboratory conditions, mimicking water level fluctuation, photoperiod and temperature. Artificial communities consisted of small populations of four softwater macrophyte species: Luronium natans, Baldellia ranunculoides ssp. repens, Eleocharis multicaulis and Hydrocotyle vulgaris. These communities were subjected to two levels of carbon dioxide and ammonium. Additionally, monocultures of Baldellia and Eleocharis were grown at a higher nutrient level combination in order to measure their competitive response in a community. Time (hydrological state) and species identity turned out to be the only consistently significant factors determining community composition. Plant performance was clearly species-dependent, while carbon dioxide and ammonium did not have major effects. The competitive response was significant in both Eleocharis and Baldellia. Competition intensity was highest in the emersed state. Carbon dioxide had a supplementary effect on the within-species performance in Luronium, Baldellia and Eleocharis, with high carbon dioxide level mainly resulting in more flowers and more stolons. Community outcomes and competitive responses in aquatic macrophytes appear difficult to predict, because of mixed life strategies and morphological and functional plasticity. We conclude that hydrological state was the only important environmental factor. The identity of the species that

  9. Water-table and discharge changes associated with the 2016-2017 seismic sequence in central Italy: hydrogeological data and a conceptual model for fractured carbonate aquifers

    Science.gov (United States)

    Petitta, Marco; Mastrorillo, Lucia; Preziosi, Elisabetta; Banzato, Francesca; Barberio, Marino Domenico; Billi, Andrea; Cambi, Costanza; De Luca, Gaetano; Di Carlo, Giuseppe; Di Curzio, Diego; Di Salvo, Cristina; Nanni, Torquato; Palpacelli, Stefano; Rusi, Sergio; Saroli, Michele; Tallini, Marco; Tazioli, Alberto; Valigi, Daniela; Vivalda, Paola; Doglioni, Carlo

    2018-01-01

    A seismic sequence in central Italy from August 2016 to January 2017 affected groundwater dynamics in fractured carbonate aquifers. Changes in spring discharge, water-table position, and streamflow were recorded for several months following nine Mw 5.0-6.5 seismic events. Data from 22 measurement sites, located within 100 km of the epicentral zones, were analyzed. The intensity of the induced changes were correlated with seismic magnitude and distance to epicenters. The additional post-seismic discharge from rivers and springs was found to be higher than 9 m3/s, totaling more than 0.1 km3 of groundwater release over 6 months. This huge and unexpected contribution increased streamflow in narrow mountainous valleys to previously unmeasured peak values. Analogously to the L'Aquila 2009 post-earthquake phenomenon, these hydrogeological changes might reflect an increase of bulk hydraulic conductivity at the aquifer scale, which would increase hydraulic heads in the discharge zones and lower them in some recharge areas. The observed changes may also be partly due to other mechanisms, such as shaking and/or squeezing effects related to intense subsidence in the core of the affected area, where effects had maximum extent, or breaching of hydraulic barriers.

  10. Impact of canal water shortages on groundwater in the Lower Bari Doab Canal system in Pakistan

    International Nuclear Information System (INIS)

    Shakir, A.S.; Rehman, H.U.; Khan, N.M.; Qazi, A.U.

    2011-01-01

    This paper presents rigorous analysis of shortage of canal water supplies, crop water requirements, and groundwater use and its quality in the command of Lower Bari Doab Canal, Pakistan. The annual canal water supplies are 36% less than the crop water requirements. This shortage further increases to 56% if actual canal supplies (averaged over last ten years) are compared with the crop water requirement. The groundwater levels are depleting at the rate of 30 to 40 cm per year in most parts of the LBDC command and this tendency of lowering may increase in future due to further increase in crop water requirements. The analysis of data for the last seven years indicate that quality of groundwater in most parts of LBDC command is generally good (64% of the area) or marginally acceptable (28%) for irrigation use. However, declining trends in groundwater quality are visible and can create long term sustain ability problems if proper remedial actions are not taken well in time. (author)

  11. Relationship between changes in the upper and lower tropospheric water vapor: A revisit

    Science.gov (United States)

    Yang, M.; Sun, D. Z.; Zhang, G. J.

    2017-12-01

    Upper tropospheric water vapor response to enhanced greenhouse gas forcing is as important as the lower tropospheric water vapor response in determining climate sensitivity. Early studies using older versions of climate models have suggested that the upper- and lower-troposphere water vapor changes are more strongly coupled in the climate models than in the observations. Here we reexamine this issue using a state-of-the-art climate model—the NCAR community model CAM5. Specifically, we have calculated the correlations between interannual variations of specific humidity in all levels of the troposphere with that at the surface in CAM5 and in the observations (as represented by the updated ERA-Interim and NCEP reanalysis). It is found that the previously noted biases in how strongly upper tropospheric water vapor and lower troposphere water vapor are linked still exist in CAM5—the change in the tropical averaged upper tropospheric water vapor is more strongly correlated with the change in the surface. However, this bias disappears in the averaged correlation obtained by averaging the point-by-point correlations over the tropics. The spatial pattern of the point-by-point correlations reveals that the better agreement between the model and the observations is related to the opposite model biases in different regions: the correlation is weaker in the model in the western Pacific, but stronger in the central and eastern Pacific. Further analysis of precipitation fields suggests that the weaker (stronger) coupling between tropospheric water vapor and surface moisture over western (central-eastern) Pacific in model is related to weaker (stronger) simulated convective activities in these regions. More specifically, during El Nino, the model has excessive deep convection in the central Pacific, but too littler deep convection in western Pacific. Implications of the results are discussed in the context of climate change as well as in the context of how to improve the model

  12. Evaluation of a mechanistic algorithm to calculate the influence of a shallow water table on hydrology sediment and pesticide transport through vegetative filter strips

    Science.gov (United States)

    Lauvernet, C.; Munoz-Carpena, R.; Carluer, N.

    2012-04-01

    Natural or introduced areas of vegetation, also known as vegetative filter strips (VFS), are a common environmental control practice to protect surface water bodies from human influence. In Europe, VFS are placed along the water network to protect from agrochemical drift during applications, in addition to runoff control. Their bottomland placement next to the streams often implies the presence of a seasonal shallow water table which can have a profound impact on the efficiency of the buffer zone (Lacas et al. 2005). A physically-based algorithm describing ponded infiltration into soils bounded by a water table, proposed by Salvucci and Enthekabi (1995), was further developed to simulate VFS dynamics by making it explicit in time, account for unsteady rainfall conditions, and by coupling to a numerical overland flow and transport model (VFSMOD) (Munoz-Carpena et al., submitted). In this study, we evaluate the importance of the presence of a shallow water table on filter efficiency (reductions in runoff, sediment and pesticide mass), in the context of all other input factors used to describe the system. Global sensitivity analysis (GSA) was used to rank the important input factors and the presence of interactions, as well as the contribution of the important factors to the output variance. GSA of VSFMOD modified for shallow water table was implemented on 2 sites selected in France because they represent different agro-pedo-climatic conditions for which we can compare the role of the factors influencing the performance of grassed buffer strips for surface runoff, sediment and pesticide removal. The first site at Morcille watershed in the Beaujolais wineyard (Rhône-Alpes) contains a very permeable sandy-clay with water table depth varying with the season (very deep in summer and shallow in winter), with a high slope (20 to 30%), and subject to strong seasonal storms (semi-continental, Mediterranean climate). The second site at La Jailliere (Loire-Atlantique, ARVALIS

  13. Water table depth fluctuations during ENSO phenomenon on different tropical peat swamp forest land covers in Katingan, Indonesia

    Science.gov (United States)

    Rossita, A.; Witono, A.; Darusman, T.; Lestari, D. P.; Risdiyanto, I.

    2018-03-01

    As it is the main role to maintain hydrological function, peatland has been a limelight since drainage construction for agriculture evolved. Drainage construction will decrease water table depth (WTD) and result in CO2 emission release to the atmosphere. Regardless of human intervention, WTD fluctuations can be affected by seasonal climate and climate variability, foremost El Niño Southern Oscillation (ENSO). This study aims to determine the correlation between rainfall in Katingan and ENSO index, analyze the pattern of WTD fluctuation of open area and forest area in 2015 (during very strong El Niño) and 2016 (during weak La Niña), calculate the WTD trendline slope during the dry season, and rainfall and WTD correlation. The result showed that open area has a sharper slope of decreasing or increasing WTD when entering the dry, compared to the forest area. Also, it is found that very strong El Niño in 2015 generated a pattern of more extreme decreasing WTD during the dry season than weak La Niña in 2016.

  14. The reconstruction of late Holocene depth-to-water-table based on testate amoebae in an eastern Australian mire

    Science.gov (United States)

    Zheng, X.; Money, S.; Hope, G.

    2017-12-01

    There are relatively few quantitative palaeo-hydrological records available in eastern Australia, and those that are available, for example from dendroclimatology and the reconstruction of lake level, are often relatively short or have a relatively coarse temporal resolution (e.g. Wilkins et al. 2013; Palmer et al. 2015). Testate amoebae, a widely used hydrological proxy in the Northern Hemisphere, were used here to reconstruct depth to water table (DWT) at Snowy Flat, which is a Sphagnum-Richea-Empodismahigh altitude (1618 m asl) shrub bog in the Australian Capital Territory, Australia. Testate amoebae were quantified in a Snowy Flat core representing 4,200 cal Y BP and the community composition was used to reconstruct DWT based on our recently established transfer functions. Results from three different types of transfer functions (Fig. 1) consistently show there was a decreasing DWT (wetter) period centred on about 3350 cal Y BP, a trend towards increased dryness from about 3300 to 2200 cal Y BP and a distinctly drier period 850 to 700 cal Y BP which was immediately followed by a wetter period from 700 to 500 cal Y BP. We discuss these episodes and trends in relation to the drivers of climatic variability in this region and in particular, by comparing our results with other south-eastern Australia records, comment on the history of the southern annular mode.

  15. The lower body muscle activation of intermediate to experienced kayakers when navigating white water.

    Science.gov (United States)

    Murtagh, Misha; Brooks, Darrell; Sinclair, Jonathan; Atkins, Stephen

    2016-11-01

    In white-water kayaking, the legs play a vital part in turning, stabilising and bracing actions. To date, there has been no reported information on neuromuscular activation of the legs in an authentic white-water environment. The aim of the current study was to identify lower body muscle activation, using 'in-boat' electromyography (EMG), whilst navigating a white-water run. Ten experienced male kayakers (age 31.5 ± 12.5 yr, intermediate to advanced experience) completed three successful runs of an international standard white-water course (grade 3 rapids), targeting right and left sides of the course, in a zigzag formation. Surface EMG (sEMG) outputs were generated, bilaterally, for the rectus femoris (RF), vastus lateralis, biceps femoris and gastrocnemius, expressed as a percentage of a dynamic maximal voluntary contraction (dMVC). Only RF showed significantly higher activation than any muscle on the left side of the body, and only on the left side of the course (P = .004; ETA(2) = 0.56). Other results showed no significant difference between muscle activation in the right and left legs during each run, nor when assessed at either the right or left side of the course (P > .05). These findings indicate that contralateral symmetry in lower limb muscle activation is evident during white-water kayaking. This symmetry may provide a stable base to allow more asymmetrical upper body and trunk movements to be fully optimised. Lower body symmetry development should be considered useful in targeted training programmes for white-water kayakers.

  16. Use of geospatial technology for delineating groundwater potential zones with an emphasis on water-table analysis in Dwarka River basin, Birbhum, India

    Science.gov (United States)

    Thapa, Raju; Gupta, Srimanta; Gupta, Arindam; Reddy, D. V.; Kaur, Harjeet

    2018-05-01

    Dwarka River basin in Birbhum, West Bengal (India), is an agriculture-dominated area where groundwater plays a crucial role. The basin experiences seasonal water stress conditions with a scarcity of surface water. In the presented study, delineation of groundwater potential zones (GWPZs) is carried out using a geospatial multi-influencing factor technique. Geology, geomorphology, soil type, land use/land cover, rainfall, lineament and fault density, drainage density, slope, and elevation of the study area were considered for the delineation of GWPZs in the study area. About 9.3, 71.9 and 18.8% of the study area falls within good, moderate and poor groundwater potential zones, respectively. The potential groundwater yield data corroborate the outcome of the model, with maximum yield in the older floodplain and minimum yield in the hard-rock terrains in the western and south-western regions. Validation of the GWPZs using the yield of 148 wells shows very high accuracy of the model prediction, i.e., 89.1% on superimposition and 85.1 and 81.3% on success and prediction rates, respectively. Measurement of the seasonal water-table fluctuation with a multiplicative model of time series for predicting the short-term trend of the water table, followed by chi-square analysis between the predicted and observed water-table depth, indicates a trend of falling groundwater levels, with a 5% level of significance and a p-value of 0.233. The rainfall pattern for the last 3 years of the study shows a moderately positive correlation ( R 2 = 0.308) with the average water-table depth in the study area.

  17. Lower Snake River Little Goose and Lower Granite Locks and Dams: Adult Fishway Systems Emergency Auxiliary Water Supply

    National Research Council Canada - National Science Library

    Wielick, Rolf

    2000-01-01

    The National Marine Fisheries Service (NMFS), Endangered Species Act, Biological Opinion issued March 2, 1995, require the US Army Corps of Engineers to develop an emergency auxiliary water supply (EAWS...

  18. The Effect of Cirrus Clouds on Water Vapor Transport in the Upper Troposphere and Lower Stratosphere

    Science.gov (United States)

    Lei, L.; McCormick, M. P.; Anderson, J.

    2017-12-01

    Water vapor plays an important role in the Earth's radiation budget and stratospheric chemistry. It is widely accepted that a large percentage of water vapor entering the stratosphere travels through the tropical tropopause and is dehydrated by the cold tropopause temperature. The vertical transport of water vapor is also affected by the radiative effects of cirrus clouds in the tropical tropopause layer. This latter effect of cirrus clouds was investigated in this research. The work focuses on the tropical and mid-latitude region (50N-50S). Water vapor data from the Microwave Limb Sounder (MLS) and cirrus cloud data from the Cloud-Aerosol Lidar and Infrared pathfinder Satellite Observation (CALIPSO) instruments were used to investigate the relationship between the water vapor and the occurrence of cirrus cloud. A 10-degree in longitude by 10-degree in latitude resolution was chosen to bin the MLS and CALIPSO data. The result shows that the maximum water vapor in the upper troposphere (below 146 hPa) is matched very well with the highest frequency of cirrus cloud occurrences. Maximum water vapor in the lower stratosphere (100 hPa) is partly matched with the maximum cirrus cloud occurrence in the summer time. The National Oceanic and Atmospheric Administration Interpolated Outgoing Longwave Radiation data and NCEP-DOE Reanalysis 2 wind data were used also to investigate the relationship between the water vapor entering the stratosphere, deep convection, and wind. Results show that maximum water vapor at 100 hPa coincides with the northern hemisphere summer-time anticyclone. The effects from both single-layer cirrus clouds and cirrus clouds above the anvil top on the water vapor entering the stratosphere were also studied and will be presented.

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

    International Nuclear Information System (INIS)

    Rashid, M.U.

    2015-01-01

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

  20. DETERMINATION OF WATER RESOURCES IN RIVERS IN THE BULGARIAN BASINS OF THE LOWER DANUBE

    Directory of Open Access Journals (Sweden)

    Plamen Iliev Ninov

    2017-04-01

    Full Text Available Object of the study is surface water bodies from category “rivers” according to Water Framework Directive 2000/60/ЕС. Surface water assessment is important for number of activities such as: water management in the country, making reports to international agencies, determining the change of the resources in the light of upcoming climate changes. The determination of water resources is based on information of hydrometric stations from the monitoring network system in the National Institute of Meteorology and Hydrology — Bulgarian Academy of Sciences (NIMH-BAS in which real ongoing and available water flows that are subject of management are registered. In the study a technology for surface water bodies in the Bulgarian basins of the lower Danube is applied which has been developed in the frame of cooperative project together with the Ministry of Environment and Water. This is absolutely true for the Bulgarian section of the Danube River basin which is expressed in big number and variety of hydrological homogeneous sections. The river flow is characterized with annual and inter-annual variability determined by climatic factors and anthropogenic influences. The main obtained results of the present hydrologic studies are the usage of transferred information from gauged to ungauged watersheds and the estimation of the surface water bodies’ resources using original regression relationships based on multiannual hydrological information from the NIMH-BAS monitoring network. The relationships delineate the hydrological homogeneous areas with similar conditions of flow formation. The estimated resources have significant usefulness for all State institutions managing the water in the Danube basin and have already been introduced in the operative and management practice.

  1. Hands-on repair of component with a lowered pool water level

    International Nuclear Information System (INIS)

    Perfect, J.F.

    1984-01-01

    The repair of a broken positioner mechanism on a TRIGA Reactor neutron collimator, with a lowered pool water level, presented a unique challenge. Radiation dose measurements were made which indicated the repair could be done safely with only 3 feet of water providing shielding over the reactor core. The entire repair project went quite well, due in large part to extensive preplanning. Repair was done safely and radiation exposures were kept well below allowable levels. Savings were significant using this method of repair compared to the alternative of dismantling the facility. (author)

  2. Hands-on repair of component with a lowered pool water level

    International Nuclear Information System (INIS)

    Perfect, J.F.

    1984-01-01

    The repair of a broken positioner mechanism on a TRIGA Reactor neutron collimator, with a lowered pool water level, presented a unique challenge. Radiation dose measurements were made which indicated the repair could be done safetly with only 3 feet of water providing shielding over the reactor core. The entire repair project went quite well, due in large part to extensive preplanning. Repair was done safely and radiation exposures were kept well below allowable levels. Savings were significant using this method of repair compared to the alternative of dismantling the facility

  3. The Effect of Water Table Fluctuation and its Salinity on Fe Crystal and Noncrystal in some Khuzestan Soils

    Directory of Open Access Journals (Sweden)

    mostafa Pajohannia

    2017-01-01

    Full Text Available Introduction: Iron is found in different forms in the soil. In the primary minerals, iron is found as Fe3+ or Fe2+ which converted to Fe2+ and released in unsuitable reduction conditions. Minerals such as sulfide or chlorine and bicarbonate can affect and change the different forms soil Fe. FeAs these elements are abundance in groundwater or soil, they are capable to react chemically with Fe and change different Fe forms and also may deposit or even leach them by increasing its solubility in the soil. Water table fluctuation is a regular phenomenon in Khuzestan that Fe forms change under these situations. The study of Fe oxide forms and its changes can be applied for evaluation of soil development. Therefore, the aim of this study is the water table fluctuation and its quality effects, and some physio-chemical properties on Fe oxides forms in non-saline and saline soils in Khuzestan. Materials and Methods: Soil samples were collected from two regions: saline (Abdolkhan and non-saline (South Susa regions. soil samples were collected from all horizons of 12 soil field studied profiles . The samples were analyzed for soil texture, pH, EC (soil: water ratio 1:5, organic carbon and aggregate stability (Kemper and Rosenau method. Fe forms also were extracted by two methods in all samples: di-tyonite sodium and ammonium oxalate extraction. Fe oxalate extracted was related to Feo (non crystal Fe and Fed-Feo was related to Fec (crystalline Fe. The Fe content were determined by atomic absorbtion spectrophotometer (AAS. Data were analysis in SAS and Excel software and results were presented. Results and Discussion: The results showed that texture were loamy sand to silty clay loam, OM was very poor (0.1-0.7%. The soil salinity was also 2.8-16.8 dS/m. Calcium carbonate equivalent was 38-40%. All pedons were classified in Entisols and Inceptisols according to Keys to soil taxonomy (2010. The results showed that the proportion of Fe with oxalate to di

  4. Optimization of ground-water withdrawal in the lower Fox River communities, Wisconsin

    Science.gov (United States)

    Walker, J.F.; Saad, D.A.; Krohelski, J.T.

    1998-01-01

    Pumping from closely spaced wells in the Central Brown County area and the Fox Cities area near the north shore of Lake Winnebago has resulted in the formation of deep cones of depression in the vicinity of the two pumping centers. Water-level measurements indicate there has been a steady decline in water levels in the vicinity of these two pumping centers for the past 50 years. This report describes the use of ground-water optimization modeling to efficiently allocate the ground-water resources in the Lower Fox River Valley. A 3-dimensional ground-water flow model was used along with optimization techniques to determine the optimal withdrawal rates for a variety of management alternatives. The simulations were conducted separately for the Central Brown County area and the Fox Cities area. For all simulations, the objective of the optimization was to maximize total ground-water withdrawals. The results indicate that ground water can supply nearly all of the projected 2030 demand for Central Brown County municipalities if all of the wells are managed (including the city of Green Bay), 8 new wells are installed, and the water-levels are allowed to decline to 100 ft below the bottom of the confining unit. Ground water can supply nearly all of the projected 2030 demand for the Fox Cities if the municipalities in Central Brown County convert to surface water; if Central Brown County municipalities follow the optimized strategy described above, there will be a considerable shortfall of available ground water for the Fox Cities communities. Relaxing the water-level constraint in a few wells, however, would likely result in increased availability of water. In all cases examined, optimization alternatives result in a rebound of the steady-state water levels due to projected 2030 withdrawal rates to levels at or near the bottom of the confining unit, resulting in increased well capacity. Because the simulations are steady-state, if all of the conditions of the model remain

  5. Geohydrology and water quality of stratified-drift aquifers in the lower Merrimack and coastal river basins, southeastern New Hampshire

    Science.gov (United States)

    Stekl, Peter J.; Flanagan, Sarah M.

    1992-01-01

    Communities in the lower Merrimack River basin and coastal river basins of southeastern New Hampshire are experiencing increased demands for water because of a rapid increase in population. The population in 1987 was 225,495 and is expected to increase by 30 percent during the next decade. As of 1987, five towns used the stratified-drift aquifers for municipal supply and withdrew an estimated 6 million gallons per day. Four towns used the bedrock aquifer for municipal supply and withdrew an average of 1 .6 million gallons per day. Stratified-drift deposits cover 78 of the 327 square miles of the study area. These deposits are generally less than 10 square miles in areal extent, and their saturated thickness ranges front less than 20 feet to as much as 100 feet . Transinissivity exceeds 4,000 square feet per day in several locations. Stratified-drift aquifers in the eastern part are predominantly small ice-contact deposits surrounded by marine sediments or till of low hydraulic conductivity. Stratified-drift aquifers in the western part consist of ice-contact and proglacial deposits that are large in areal extent and are commonly in contact with surface-water bodies. Five stratified-drift aquifers, in the towns of Derry, Windham, Kingston, North Hampton, and Greenland, have the greatest potential to supply additional amounts of water. Potential yields and contributing areas of hypothetical supply wells were estimated for an aquifer in Windham near Cobbetts Pond and for an aquifer in Kingston along the Powwow River by use of a method analogous to superposition in conjunction with a numerical ground-waterflow model. The potential yield is estimated to be 0 .6 million gallons per day for the Windham-Cobbetts Pond aquifer and 4 .0 million gallons per day for the Kingston-Powwow River aquifer. Contributing recharge area for supply wells is estimated to be 1.6 square miles in the Windham-Cobbetts Pond aquifer and 4.9 square miles in the Kingston-Powwow River aquifer

  6. Comparison of groundwater transit velocity estimates from flux theory and water table recession based approaches for solute transport.

    Science.gov (United States)

    Rasiah, Velu; Armour, John David

    2013-02-15

    Reliable information in transit time (TT) derived from transit velocity (TV) for rain or irrigation water to mix with groundwater (GW) and the subsequent discharge to surface water bodies (SWB) is essential to address the issues associated with the transport of nutrients, particularly nitrate, from GW to SWB. The objectives of this study are to (i) compare the TV estimates obtained using flux theory-based (FT) approach with the water table rise/recession (WT) rate approach and (ii) explore the impact of the differences on solute transport from GW to SWB. The results from a study conducted during two rainy seasons in the northeast humid tropics of Queensland, Australia, showed the TV varied in space and over time and the variations depended on the estimation procedures. The lateral TV computed using the WT approach ranged from 1.00 × 10(-3) to 2.82 × 10(-1) m/d with a mean of 6.18 × 10(-2) m/d compared with 2.90 × 10(-4) to 5.15 × 10(-2) m/d for FT with a mean of 2.63 × 10(-2) m/d. The vertical TV ranged from 2.00 × 10(-3) to 6.02 × 10(-1) m/d with a mean of 1.28 × 10(-1) m/d for the WT compared with 6.76 × 10(-3)-1.78 m/d for the FT with a mean of 2.73 × 10(-1) m/d. These differences are attributed to the role played by different flow pathways. The bypass flow pathway played a role only in WT but not in FT. Approximately 86-95% of the variability in lateral solute transport was accounted for by the lateral TV and the total recession between two consecutive major rainfall events. A comparison of TT from FT and WT approaches indicated the laterally transported nitrate from the GW to the nearby creek was relatively 'new', implying the opportunity for accumulation and to undergo biochemical reactions in GW was low. The results indicated the WT approach produced more reliable TT estimates than FT in the presence of bypass flow pathways. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Water-quality assessment of the lower Illinois River Basin; environmental setting

    Science.gov (United States)

    Warner, Kelly L.

    1998-01-01

    The lower Illinois River Basin (LIRB) encompasses 18,000 square miles of central and western Illinois. Historical and recent information from Federal, State, and local agencies describing the physiography, population, land use, soils, climate, geology, streamflow, habitat, ground water, water use, and aquatic biology is summarized to describe the environmental setting of the LIRB. The LIRB is in the Till Plains Section of the Central Lowland physiographic province. The basin is characterized by flat topography, which is dissected by the Illinois River. The drainage pattern of the LIRB has been shaped by many bedrock and glacial geologic processes. Erosion prior to and during Pleistocene time created wide and deep bedrock valleys. The thickest deposits and most major aquifers are in buried bedrock valleys. The Wisconsinan glaciation, which bisects the northern half of the LIRB, affects the distribution and characteristics of glacial deposits in the basin. Agriculture is the largest land use and forested land is the second largest land use in the LIRB. The major urban areas are near Peoria, Springfield, Decatur, and Bloomington-Normal. Soil type and distribution affect the amount of soil erosion, which results in sedimentation of lakes and reservoirs in the basin. Rates of soil erosion of up to 2 percent per year of farmland soil have been measured. Many of the 300 reservoirs, lakes, and wetlands are disappearing because of sedimentation resulting from agriculture activities, levee building, and urbanization. Sedimentation and the destruction of habitat appreciably affect the ecosystem. The Illinois River is a large river-floodplain ecosystem where biological productivity is enhanced by annual flood pulses that advance and retreat over the flood plain and temporarily expand backwater and flood-plain lakes. Ground-water discharge to streams affects the flow and water quality of the streams. The water budget of several subbasins show variability in ground-water

  8. The Water Level and Transport Regimes of the Lower Columbia River

    Science.gov (United States)

    Jay, D. A.

    2011-12-01

    Tidal rivers are vital, spatially extensive conduits of material from land to sea. Yet the tidal-fluvial regime remains poorly understood relative to the bordering fluvial and estuarine/coastal regimes with which it interacts. The 235km-long Lower Columbia River (LCR) consists of five zones defined by topographic constrictions: a 5km-long ocean-entrance, the lower estuary (15km), an energy-minimum (67km), the tidal river (142km), and a landslide zone (5km). Buoyant plume lift-off occurs within the entrance zone, which is dominated by tidal and wave energy. The lower estuary is strongly tidally, amplifies the semidiurnal tide, and has highly variable salinity intrusion. Tidal and fluvial influences are balanced in the wide energy-minimum, into which salinity intrudes during low-flow periods. It has a turbidity maximum and a dissipation minimum at its lower end, but a water-level variance minimum at its landward end. The tidal river shows a large increase in the ratio of fluvial-to-tidal energy in the landward direction and strong seasonal variations in tidal properties. Because tidal monthly water level variations are large, low waters are higher on spring than neap tides. The steep landslide zone has only weak tides and is the site of the most seaward hydropower dam. Like many dammed systems, the LCR has pseudo-tides: daily and weakly hydropower peaking waves that propagate seaward. Tidal constituent ratios vary in the alongchannel direction due to frictional non-linearities, the changing balance of dissipation vs. propagation, and power peaking. Long-term changes to the system have occurred due to climate change and direct human manipulation. Flood control, hydropower regulation, and diversion have reduced peak flows, total load and sand transport by ~45, 50 and 80%, respectively, causing a blue-shift in the flow and water level power spectra. Overbank flows have been largely eliminated through a redundant combination of diking and flow regulation. Export of sand

  9. Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon

    Science.gov (United States)

    Torgersen, Christian E.; Hockman-Wert, David P.; Bateman, Douglas S.; Leer, David W.; Gresswell, Robert E.

    2007-01-01

    The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National Wild and Scenic Rivers Act (16 U.S.C. 1271-1287) for its outstandingly remarkable scenic, recreational, geologic, hydrologic, wildlife, and botanical values (ORVs), and significant fishery and cultural values. Groundwater springs flow directly out of the canyon walls into the Lower Crooked River and create a unique hydrologic setting for native coldwater fish, such as inland Columbia Basin redband trout (Oncorhynchus mykiss gairdneri). To protect and enhance the ORVs that are the basis for the wild and scenic designation, the Bureau of Land Management (BLM) has identified the need to evaluate, among other conditions, fish presence and habitat use of the Lower Crooked River. The results of this and other studies will provide a scientific basis for communication and cooperation between the BLM, Oregon Water Resources Department, Oregon Department of Fish and Wildlife (ODFW) and all water users within the basin. These biological studies initiated by the BLM in the region reflect a growing national awareness of the impacts of agricultural and municipal water use on the integrity of freshwater ecosystems.

  10. Nonlinear response of tropical lower-stratospheric temperature and water vapor to ENSO

    Directory of Open Access Journals (Sweden)

    C. I. Garfinkel

    2018-04-01

    Full Text Available A series of simulations using the NASA Goddard Earth Observing System Chemistry–Climate Model are analyzed in order to aid in the interpretation of observed interannual and sub-decadal variability in the tropical lower stratosphere over the past 35 years. The impact of El Niño–Southern Oscillation on temperature and water vapor in this region is nonlinear in boreal spring. While moderate El Niño events lead to cooling in this region, strong El Niño events lead to warming, even as the response of the large-scale Brewer–Dobson circulation appears to scale nearly linearly with El Niño. This nonlinearity is shown to arise from the response in the Indo-West Pacific to El Niño: strong El Niño events lead to tropospheric warming extending into the tropical tropopause layer and up to the cold point in this region, where it allows for more water vapor to enter the stratosphere. The net effect is that both strong La Niña and strong El Niño events lead to enhanced entry water vapor and stratospheric moistening in boreal spring and early summer. These results lead to the following interpretation of the contribution of sea surface temperatures to the decline in water vapor in the early 2000s: the very strong El Niño event in 1997/1998, followed by more than 2 consecutive years of La Niña, led to enhanced lower-stratospheric water vapor. As this period ended in early 2001, entry water vapor concentrations declined. This effect accounts for approximately one-quarter of the observed drop.

  11. Nonlinear response of tropical lower-stratospheric temperature and water vapor to ENSO

    Science.gov (United States)

    Garfinkel, Chaim I.; Gordon, Amit; Oman, Luke D.; Li, Feng; Davis, Sean; Pawson, Steven

    2018-04-01

    A series of simulations using the NASA Goddard Earth Observing System Chemistry-Climate Model are analyzed in order to aid in the interpretation of observed interannual and sub-decadal variability in the tropical lower stratosphere over the past 35 years. The impact of El Niño-Southern Oscillation on temperature and water vapor in this region is nonlinear in boreal spring. While moderate El Niño events lead to cooling in this region, strong El Niño events lead to warming, even as the response of the large-scale Brewer-Dobson circulation appears to scale nearly linearly with El Niño. This nonlinearity is shown to arise from the response in the Indo-West Pacific to El Niño: strong El Niño events lead to tropospheric warming extending into the tropical tropopause layer and up to the cold point in this region, where it allows for more water vapor to enter the stratosphere. The net effect is that both strong La Niña and strong El Niño events lead to enhanced entry water vapor and stratospheric moistening in boreal spring and early summer. These results lead to the following interpretation of the contribution of sea surface temperatures to the decline in water vapor in the early 2000s: the very strong El Niño event in 1997/1998, followed by more than 2 consecutive years of La Niña, led to enhanced lower-stratospheric water vapor. As this period ended in early 2001, entry water vapor concentrations declined. This effect accounts for approximately one-quarter of the observed drop.

  12. Availability of ground water in the lower Pawcatuck River basin, Rhode Island

    Science.gov (United States)

    Gonthier, Joseph B.; Johnston, Herbert E.; Malmberg, Glenn T.

    1974-01-01

    The lower Pawcatuck River basin in southwestern Rhode Island is an area of about 169 square miles underlain by crystalline bedrock over which lies a relatively thin mantle of glacial till and stratified drift. Stratified drift, consisting dominantly of sand and gravel, occurs in irregularly shaped linear deposits that are generally less than a mile wide and less than 125 feet thick; these deposits are found along the Pawcatuck River, its tributaries, and abandoned preglacial channels. Deposits of stratified sand and gravel constitute the principal aquifer in the lower Pawcatuck basin and the only one capable of sustaining yields of 100 gallons per minute or more to individual wells. Water available for development in this aquifer consists of water in storage--potential ground-water runoff to streams--plus infiltration that can be induced from streams. Minimum annual ground-water runoff from the sand and gravel aquifer is calculated to be at least 1.17 cubic feet per second per square mile, or 0.76 million gallons per day per square mile. Potential recharge by induced infiltration is estimated to range from about 250 to 600 gallons per day per linear foot of streambed for the principal streams. In most areas, induced infiltration from streams constitutes the major source of water potentially available for development by wells. Because subsurface hydraulic connection in the sand and gravel aquifer is poor in several places, the deposits are conveniently divisible into several ground-water reservoirs. The potential yield from five of the most promising ground-water reservoirs is evaluated by means of mathematical models. Results indicate that continuous withdrawals ranging from 1.3 to 10.3 million gallons per day, and totaling 31 million gallons per day, are obtainable from these reservoirs. Larger yields may be recovered by different well placement, spacing, construction and development, pumping practice, and so forth. Withdrawals at the rates indicated will reduce

  13. Ground-Penetrating-Radar Profiles of Interior Alaska Highways: Interpretation of Stratified Fill, Frost Depths, Water Table, and Thaw Settlement over Ice-Rich Permafrost

    Science.gov (United States)

    2016-08-01

    along either massive ice surfaces or within sections of segregated ice. The uninsulated ice surface at Tok in Figure 17B is irregular. All of the...ER D C/ CR RE L TR -1 6- 14 ERDC’s Center-Directed Research Program Ground -Penetrating-Radar Profiles of Interior Alaska Highways...August 2016 Ground -Penetrating-Radar Profiles of Interior Alaska Highways Interpretation of Stratified Fill, Frost Depths, Water Table, and Thaw

  14. Ecologization of water-land property matters on the territory of the Tom lower course

    Science.gov (United States)

    Popov, V. K.; Kozina, M. V.; Levak, Yu Yu; Shvagrukova, E. V.

    2016-03-01

    In the present paper the water-land property complex is considered as a strategic resource of the city development. The formulated question is expounded through the example of water-land property complex usage on the territory of the Tom lower course for land-use planning and developing the systems of water recourses management and land tenure. Consequences of liquid radioactive waste (LRW) landfilling are investigated in terms of arable farming. Also, forming a water budget of the soils spread on the area of the Tomsk underground water supply cone of depression and its role in the development of agricultural industry are studied. The main aspect of the analysis is the incorporation of social, economic, and ecological requirements for the system of life-supporting branches of municipal economy and social services. As far as the system of land tax payments plays an important role in land property complex management, the common issues and tendencies are specified in the paper. These problems are concerned with the inadequate incorporation of an ecological constituent in the methods of cadastral valuation of lands, as well as the situation of the narrow area of its results usage in the Russian Federation. Natural factors (hydrological, territorial, geological (geomorphologic) territory conditions) are combined by the authors into a special group. These factors should be reflected in the results of cadastral valuation. Also, in order to protect the interests of water consumers, it is offered to establish the Water Consumers Association based on the international experience of such countries as Spain and Uzbekistan.

  15. Accounting for intracell flow in models with emphasis on water table recharge and stream-aquifer interaction: 1. Problems and concepts

    Science.gov (United States)

    Jorgensen, Donald G.; Signor, Donald C.; Imes, Jeffrey L.

    1989-01-01

    Intracell flow is important in modeling cells that contain both sources and sinks. Special attention is needed if recharge through the water table is a source. One method of modeling multiple sources and sinks is to determine the net recharge per cell. For example, for a model cell containing both a sink and recharge through the water table, the amount of recharge should be reduced by the ratio of the area of influence of the sink within the cell to the area of the cell. The reduction is the intercepted portion of the recharge. In a multilayer model this amount is further reduced by a proportion factor, which is a function of the depth of the flow lines from the water table boundary to the internal sink. A gaining section of a stream is a typical sink. The aquifer contribution to a gaining stream can be conceptualized as having two parts; the first part is the intercepted lateral flow from the water table and the second is the flow across the streambed due to differences in head between the water level in the stream and the aquifer below. The amount intercepted is a function of the geometry of the cell, but the amount due to difference in head across the stream bed is largely independent of cell geometry. A discharging well can intercept recharge through the water table within a model cell. The net recharge to the cell would be reduced in proportion to the area of influence of the well within the cell. The area of influence generally changes with time. Thus the amount of intercepted recharge and net recharge may not be constant with time. During periods when the well is not discharging there will be no intercepted recharge even though the area of influence from previous pumping may still exist. The reduction of net recharge per cell due to internal interception of flow will result in a model-calculated mass balance less than the prototype. Additionally the “effective transmissivity” along the intercell flow paths may be altered when flow paths are occupied by

  16. Irrigation solutions in open fractures of the lower extremities: evaluation of isotonic saline and distilled water.

    Science.gov (United States)

    Olufemi, Olukemi Temiloluwa; Adeyeye, Adeolu Ikechukwu

    2017-01-01

    Open fractures are widely considered as orthopaedic emergencies requiring immediate intervention. The initial management of these injuries usually affects the ultimate outcome because open fractures may be associated with significant morbidity. Wound irrigation forms one of the pivotal principles in the treatment of open fractures. The choice of irrigation fluid has since been a source of debate. This study aimed to evaluate and compare the effects of isotonic saline and distilled water as irrigation solutions in the management of open fractures of the lower extremities. Wound infection and wound healing rates using both solutions were evaluated. This was a prospective hospital-based study of 109 patients who presented to the Accident and Emergency department with open lower limb fractures. Approval was sought and obtained from the Ethics Committee of the Hospital. Patients were randomized into either the isotonic saline (NS) or the distilled water (DW) group using a simple ballot technique. Twelve patients were lost to follow-up, while 97 patients were available until conclusion of the study. There were 50 patients in the isotonic saline group and 47 patients in the distilled water group. Forty-one (42.3%) of the patients were in the young and economically productive strata of the population. There was a male preponderance with a 1.7:1 male-to-female ratio. The wound infection rate was 34% in the distilled water group and 44% in the isotonic saline group (p = 0.315). The mean time ± SD to wound healing was 2.7 ± 1.5 weeks in the distilled water group and 3.1 ± 1.8 weeks in the isotonic saline group (p = 0.389). It was concluded from this study that the use of distilled water compares favourably with isotonic saline as an irrigation solution in open fractures of the lower extremities. © The Authors, published by EDP Sciences, 2017.

  17. Irrigation solutions in open fractures of the lower extremities: evaluation of isotonic saline and distilled water

    Directory of Open Access Journals (Sweden)

    Olufemi Olukemi Temiloluwa

    2017-01-01

    Full Text Available Introduction: Open fractures are widely considered as orthopaedic emergencies requiring immediate intervention. The initial management of these injuries usually affects the ultimate outcome because open fractures may be associated with significant morbidity. Wound irrigation forms one of the pivotal principles in the treatment of open fractures. The choice of irrigation fluid has since been a source of debate. This study aimed to evaluate and compare the effects of isotonic saline and distilled water as irrigation solutions in the management of open fractures of the lower extremities. Wound infection and wound healing rates using both solutions were evaluated. Methods: This was a prospective hospital-based study of 109 patients who presented to the Accident and Emergency department with open lower limb fractures. Approval was sought and obtained from the Ethics Committee of the Hospital. Patients were randomized into either the isotonic saline (NS or the distilled water (DW group using a simple ballot technique. Twelve patients were lost to follow-up, while 97 patients were available until conclusion of the study. There were 50 patients in the isotonic saline group and 47 patients in the distilled water group. Results: Forty-one (42.3% of the patients were in the young and economically productive strata of the population. There was a male preponderance with a 1.7:1 male-to-female ratio. The wound infection rate was 34% in the distilled water group and 44% in the isotonic saline group (p = 0.315. The mean time ± SD to wound healing was 2.7 ± 1.5 weeks in the distilled water group and 3.1 ± 1.8 weeks in the isotonic saline group (p = 0.389. Conclusions: It was concluded from this study that the use of distilled water compares favourably with isotonic saline as an irrigation solution in open fractures of the lower extremities.

  18. Environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks, New Jersey Coastal Plain, USA: migration to the water table.

    Science.gov (United States)

    Szabo, Zoltan; Jacobsen, Eric; Kraemer, Thomas F; Parsa, Bahman

    2010-01-01

    Fate of radium (Ra) in liquid regeneration brine wastes from water softeners disposed to septic tanks in the New Jersey Coastal Plain was studied. Before treatment, combined Ra ((226)Ra plus (228)Ra) concentrations (maximum, 1.54 Bq L(-1)) exceeded the 0.185 Bq L(-1) Maximum Contaminant Level in 4 of 10 studied domestic-well waters (median pH, 4.90). At the water table downgradient from leachfields, combined Ra concentrations were low (commonly 5.3, indicating sequestration; when pH was septic-tank effluents (maximum, 0.243 Bq L(-1))), indicating Ra mobilization from leachfield sediments. Confidence in quantification of Ra mass balance was reduced by study design limitations, including synoptic sampling of effluents and ground waters, and large uncertainties associated with analytical methods. The trend of Ra mobilization in acidic environments does match observations from regional water-quality assessments.

  19. Airborne Observations of Water Vapor Deuterium Excess in the Mid-Latitude Lower Troposphere

    Science.gov (United States)

    Salmon, O. E.; Welp, L.; Shepson, P. B.; Stirm, B. H.

    2017-12-01

    Water vapor is responsible for over half of the natural atmospheric greenhouse effect. As global temperatures increase due to fossil fuel combustion, atmospheric water vapor concentrations are also expected to increase in positive feedback. Additionally, studies have shown that urban areas can influence humidity levels, and the frequency and intensity of precipitation events. It is thus important to understand anthropogenic modification of the hydrological cycle, particularly around urban areas, where over half of the world's population resides. Airborne measurements of water vapor isotopologues containing 2H and 18O were conducted to better understand processes influencing atmospheric moisture levels around urban areas. Airborne measurements were conducted around the Indianapolis and Washington, D.C.-Baltimore areas during afternoon hours in February and March 2016, using a Los Gatos Research Water Vapor Isotope Analyzer installed in Purdue University's experimental aircraft, the Airborne Laboratory for Atmospheric Research. The measurements of 2H and 18O allow for the calculation of deuterium excess (= δ2H - 8*δ18O), which provides information about non-equilibrium processes, such as kinetic effects, air parcel mixing, and transpiration. There are few studies that have reported observations of deuterium excess above the surface level ( 100 m). During the measurement campaign, vertical profiles were frequently conducted from 300 m above the ground to an altitude of approximately 1.5 km, effectively characterizing water vapor isotope profiles spanning the boundary layer and lower free troposphere. Measurements probed the transition from planetary boundary layer air to free troposphere air to provide high resolution deuterium excess information across this interface. Processes such as Rayleigh distillation, atmospheric mixing, and surface fluxes potentially impacting water vapor deuterium excess through the boundary layer and free troposphere with be discussed.

  20. Cold water immersion of the ankle decreases neuromuscular response of lower limb after inversion movement

    Directory of Open Access Journals (Sweden)

    Christiane S. G. Macedo

    2014-03-01

    Full Text Available BACKGROUND: Cryotherapy has been associated with a significant decrease in nerve conduction velocity and muscle contraction with possible effects on exercise and physical training. OBJECTIVES: To quantify the electromyographic response of the lateral gastrocnemius, tibialis anterior, fibularis longus, rectus femoris and gluteus medius to ankle inversion following cold water immersion. METHOD: The peak values of the root mean square (RMS were obtained from 35 healthy and active university subjects after the use of a tilt platform to force the ankle into 30° of inversion before, immediately after, and 10, 20, and 30 minutes after water immersion at 4±2°C, for 20 minutes. The Shapiro-Wilk test, repeated measures analysis, Bonferroni's post-hoc, and linear regression analysis provided the results. RESULTS: Peak RMS was significantly lower at all times after cold water immersion, with residual effect of up to 30 minutes, when compared to pre-immersion for all muscles, except for immediate post-immersion for the gluteus medius. CONCLUSIONS: After cold water immersion of the ankle, special care should be taken in activities that require greater neuromuscular control.

  1. Cold water immersion of the ankle decreases neuromuscular response of lower limb after inversion movement.

    Science.gov (United States)

    Macedo, Christiane S G; Alonso, Carolina S; Liporaci, Rogério F; Vieira, Fernando; Guirro, Rinaldo R J

    2014-01-01

    Cryotherapy has been associated with a significant decrease in nerve conduction velocity and muscle contraction with possible effects on exercise and physical training. To quantify the electromyographic response of the lateral gastrocnemius, tibialis anterior, fibularis longus, rectus femoris and gluteus medius to ankle inversion following cold water immersion. The peak values of the root mean square (RMS) were obtained from 35 healthy and active university subjects after the use of a tilt platform to force the ankle into 30° of inversion before, immediately after, and 10, 20, and 30 minutes after water immersion at 4±2°C, for 20 minutes. The Shapiro-Wilk test, repeated measures analysis, Bonferroni's post-hoc, and linear regression analysis provided the results. Peak RMS was significantly lower at all times after cold water immersion, with residual effect of up to 30 minutes, when compared to pre-immersion for all muscles, except for immediate post-immersion for the gluteus medius. After cold water immersion of the ankle, special care should be taken in activities that require greater neuromuscular control.

  2. Impacts of hydropower operation on water supply from lower Colorado River in Texas

    International Nuclear Information System (INIS)

    Martin, Q.W.

    1993-01-01

    The Lower Colorado River Authority (LCRA) of Texas is both a water and energy supplier to a large area of Central Texas. LCRA generates approximately 10 percent of its power from hydroelectric power plants on the six dams in the Highland Lakes system of reservoirs. To improve power production, LCRA has investigated alternative operating procedures to increase the winter scheduling of hydroelectric power generation in the upper reservoirs of the Highland Lakes system without adversely impacting available water supplies. A methodology using both optimization and simulation techniques was developed to evaluate the ability of the hydroelectric facilities to meet weather-related winter peaking requirements. A linear programming procedure determined the hourly power generation schedule, over a 24 hour period, that maximized the total amount of power generated over the six hours of peak power demand. The full installed capacity was found to be available during the peak hours without violating system operating constraints including water storage limits at the individual lakes. Based on statistical simulation of daily winter inflows and releases using a LOTUS 1-2-3 spreadsheet, it was found that the full generating capacity could be supplied to meet the weather-related peak winter power demand with no significant impact on water availability

  3. Analytical models for lower and upper bounds of the condensation-induced water hammer in long horizontal pipes

    International Nuclear Information System (INIS)

    Chun, Moon Hyun; Park, Joo Wan; Nam, Ho Yun

    1992-01-01

    Improved analytical models have been proposed that can predict the lower and upper limits of the water hammer region for given flow conditions by incorporation of recent advances made in the understanding of phenomena associated with the condensation-induced water hammer into existing methods. Present models are applicable for steam-water counterflow in a long horizontal pipe geometry. Both lower and upper bounds of the water hammer region are expressed in terms of the 'critical inlet water flow rate' as a function of axial position. Water hammer region boundaries predicted by present and typical existing models are compared for particular flow conditions of the water hammer event occurred at San Onofre Unit 1 to assess the applicability of the models examined. The result shows that present models for lower and upper bounds of the water hammer region compare favorably with the best performing existing models

  4. Direct hydrodeoxygenation of cellulose and xylan to lower alkanes on ruthenium catalysts in subcritical water

    International Nuclear Information System (INIS)

    Osaka, Yuriko; Ikeda, Yoichi; Hashizume, Daisuke; Iwamoto, Masakazu

    2013-01-01

    Nano particles of Ru, Rh, Pd, Ir, Pt, and Au, protected by polyvinyl pyrrolidone (PVP), were applied to the hydrodeoxygenation of cellulose and xylan in water and 5 MPa H 2 at 543 K. The distributions of products generated from cellulose and xylan were roughly similar to each other under the present reaction conditions, and therefore, the former was intensively studied. The Ru-PVP catalyst afforded mainly methane and lower alkanes, rather than producing water soluble organic compounds, such as diols and alcohols, that were formed with the use of the other catalysts. The changes in the product distributions with reaction temperature and time indicated that the reaction consisted of two consecutive reactions: cellulose or xylan → water soluble compounds → hydrogenolysis. The first transformation was promoted in subcritical water, and the second step was catalyzed by the Ru catalyst. The Ru catalyst that was supported on CeO 2 , γ-Al 2 O 3 , or activated carbon yielded a similar product distribution to that on Ru-PVP; however, the loading of Ru on TiO 2 , ZrO 2 , SiO 2 –Al 2 O 3 , or SiO 2 resulted in the increment of diols. After the reaction a small portion of the CeO 2 and most of the SiO 2 –Al 2 O 3 and SiO 2 were dissolved in water, and a portion of the Al 2 O 3 was transformed to boehmite AlO(OH) from the γ-alumina. Little change in the catalytic activity however was observed upon the reuse of Ru/Al 2 O 3 in the second run. Highlights: •One-path hydrodeoxygenation of cellulose and xylan to methane and lower alkanes was studied. •Ru-PVP catalysts gave the best yields among Ru-, Rh-, Pd-, Ir-, Pt-, and Au-PVP. •The reaction pathways were cellulose → water soluble compounds → hydrogenolysis. •The catalytic activity of Ru was greatly dependent on the supports

  5. Scanning table

    CERN Multimedia

    1960-01-01

    Before the invention of wire chambers, particles tracks were analysed on scanning tables like this one. Today, the process is electronic and much faster. Bubble chamber film - currently available - (links can be found below) was used for this analysis of the particle tracks.

  6. Economic feasibility of promoting species of lower water requirements to improve water condition of lake Urmia using of PES schemes

    International Nuclear Information System (INIS)

    Daneshi, A.; Panahi, M.; Vafakhah, M.

    2016-01-01

    Since agricultural sector is considered as the biggest user of freshwater resources in Iran, one of the major factors of Urmia lake drying might be attributed to unsustainable development of agricultural activities. Therefore, it would be of interest to focus the lake restoration measures on water usage management in agricultural sector. It seems that a program to change cropping pattern based on the use of species with lower water requirements instead of higher water need ones is an effective policy. In this study, we attempted firstly, to propose to farmers change in cropping pattern by replacing the sugar beet, alfalfa, corn and tomato with wheat and barley as a solution. Then, results of the survey have been assessed in economic terms. Area in which the survey has been undertaken is Simineh Rud basin. To collect data, a combined techniques of interview and questionnaires have been used. The results of this study showed that this program has sufficient acceptability to the farmers (in 2014) and in case of having financial support by government, it will have successful implementation. Meanwhile, from technical and economic point of view, implementation of such a program has benefit-cost ratio of 2.12 for wheat and 2.06 for barley. Therefore, based on feasibility of such proposal, allocating required budgets, implementing the proposed plan in all other sub-basins of Urmia lake and paying income deficit caused by change in cropping pattern to farmers may suggested.

  7. Long-term rise of the Water Table in the Northeast US: Climate Variability, Land-Use Change, or Angry Beavers?

    Science.gov (United States)

    Boutt, D. F.

    2011-12-01

    The scientific evidence that humans are directly influencing the Earth's natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research suggests that the Northeast region of the U.S. is experiencing significant changes to its' natural climate and hydrologic systems. Previous analysis of a long-term regional compilation of the water table response to the last 60 years of climate variability in New England documented a wide range of variability. The investigation evaluated the physical mechanisms, natural variability and response of aquifers in New England using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations. Groundwater trends were calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Interestingly, a trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most (80 out of 100) well sites. In this contribution we investigate the causal mechanisms behind the observed ground water level trends using site-by-site land-use change assessments, cluster analysis, and spatial analysis of beaver populations (a possible proxy for beaver activity). Regionally, average annual precipitation has been slightly increasing since 1900, with 95% of the stations having statistically significant positive trends. Despite this, no correlation is observed between the magnitude of the annual precipitation trends and the magnitude of the groundwater level changes. Land-use change throughout the region has primarily taken

  8. Impact of Gold mining activities on the water quality of the lower pra river

    International Nuclear Information System (INIS)

    Dwamena, Offei Samuel K.

    2013-07-01

    This study was conducted to assess the extent of Mercury (THg) contamination at four locations within the Shama-Mporhor Wassa catchment area of the Lower Pra River. Water, fish and sediment samples were taken twice with the longitudinal transect method at Daboase, Beposo, Bokorkope and Shama during the minor rainy season in October and at the apex of the dry season in March. Careful investigation of the Shama-Mporhor Wassa catchment area revealed that two of the locations Daboase and Beposo had been continuously impacted by the activities of Artisanal Gold miners (AGM). From the study, Total Mercury (THg) levels were found to have persisted in River water several kilometers downstream the second Artisanal Gold mining (AGM) location at Shama estuary for both seasons. Ten trace elements Mercury (Hg), Selenium (Se), Copper (Cu), Chromium (Cr), Lead (Pb), Iron (Fe), Manganese (Mn), Nickel (Ni), Zinc (Zn) and Cadmium (Cd) were determined in water, fish and sediment samples using the Atomic Absorption Spectroscopy (AAS) equipped with both Hydride Generation (HGAAS) for Selenium (Se) and Cold Vapour (CVAAS) for Total Mercury (THg). The levels of Total Mercury (THg) were largely above the WHO and USEPA guidelines for drinking water (1μg/L) and sediments (200 μg/Kg) respectively for the four locations investigated. Total Mercury (THg) exceeded the WHO, 2011 guideline value of 0.5 mg/Kg for fish species Clarias submarginatus but was below the guideline value for Xenomystus nigri. Mean concentration of Cd and Fe exceeded the WHO, 2011 guideline values for drinking water for the wet season. The other trace elements Zn, Ni, Cu, Cr, Se, Mn, and Pb had their mean concentration below the WHO, 2011 guideline values for drinking water. Apart from the mean concentration of Cd that exceeded the Canadian Interim Sediment Quality (ISQG) guideline value of 0.6 mg/Kg for the wet season, Cr, Cu, Zn, Ni and Pb were below their respective guideline values for both seasons. Statistical

  9. Explosive lower limb extension mechanics: An on-land vs. in-water exploratory comparison.

    Science.gov (United States)

    Guignard, Brice; Lauer, Jessy; Samozino, Pierre; Mourão, Luis; Vilas-Boas, João Paulo; Rouard, Annie Hélène

    2017-12-08

    During a horizontal underwater push-off, performance is strongly limited by the presence of water, inducing resistances due to its dense and viscous nature. At the same time, aquatic environments offer a support to the swimmer with the hydrostatic buoyancy counteracting the effects of gravity. Squat jump is a vertical terrestrial push-off with a maximal lower limb extension limited by the gravity force, which attracts the body to the ground. Following this observation, we characterized the effects of environment (water vs. air) on the mechanical characteristics of the leg push-off. Underwater horizontal wall push-off and vertical on-land squat jumps of two local swimmers were evaluated with force plates, synchronized with a lateral camera. To better understand the resistances of the aquatic movement, a quasi-steady Computational Fluid Dynamics (CFD) analysis was performed. The force-, velocity- and power-time curves presented similarities in both environments corresponding to a proximo-distal joints organization. In water, swimmers developed a three-step explosive rise of force, which the first one mainly related to the initiation of body movement. Drag increase, which was observed from the beginning to the end of the push-off, related to the continuous increase of body velocity with high values of drag coefficient (C D ) and frontal areas before take-off. Specifically, with velocity, frontal area was the main drag component to explain inter-individual differences, suggesting that the streamlined position of the lower limbs is decisive to perform an efficient push-off. This study motivates future CFD simulations under more ecological, unsteady conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Total dissolved gas, barometric pressure, and water temperature data, lower Columbia River, Oregon and Washington, 1996

    Science.gov (United States)

    Tanner, Dwight Q.; Harrison, Howard E.; McKenzie, Stuart W.

    1996-01-01

    Increased levels of total dissolved gas pressure can cause gas-bubble trauma in fish downstream from dams on the Columbia River. In cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey collected data on total dissolved gas pressure, barometric pressure, water temperature, and dissolved oxygen pressure at 11 stations on the lower Columbia River from the John Day forebay (river mile 215.6) to Wauna Mill (river mile 41.9) from March to September 1996. Methods of data collection, review, and processing are described in this report. Summaries of daily minimum, maximum, and mean hourly values are presented for total dissolved gas pressure, barometric pressure, and water temperature. Hourly values for these parameters are presented graphically. Dissolved oxygen data are not presented in this report because the quality-control data show that the data have poor precision and high bias. Suggested changes to monitoring procedures for future studies include (1) improved calibration procedures for total dissolved gas and dissolved oxygen to better define accuracy at elevated levels of supersaturation and (2) equipping dissolved oxygen sensors with stirrers because river velocities at the shoreline monitoring stations probably cannot maintain an adequate flow of water across the membrane surface of the dissolved oxygen sensor.

  11. Assessment of Shallow-Water Habitat Availability in Modified Dike Structures, Lower Missouri River, 2004

    Science.gov (United States)

    Jacobson, Robert B.; Elliott, Caroline M.; Johnson, Harold E.

    2004-01-01

    This study documented the effects of wing-dike notching on the availabilit of shallow water habitat in the Lower Missouri River. Five wing dikes were surveyed in late May 2004 after they were notched in early May as part of shallow-water habitat (SWH) rehabilitation activities undertaken by the U.S. Army Corps of Engineers. Surveys included high-resolution hydroacoustic depth, velocity, and substrate mapping. Relations of bottom elevations within the wing dike fields to index discharges and water-surface elevations indicate that little habitat meeting the SWH definition was created immediately following notching. This result is not unexpected, as significant geomorphic adjustment may require large flow events. Depth, velocity, and substrate measurements in the post-rehabilitation time period provide baseline data for monitoring ongoing changes. Differences in elevation and substrate were noted at all sites. Most dike fields showed substantial aggradation and replacement of mud substrate with sandier sediment, although the changes did not result in increased availability of SWH at the index discharge. It is not known how much of the elevation and substrate changes can be attributed directly to notching and how much would result from normal sediment transport variation.

  12. Stochastic simulation of time-series models combined with geostatistics to predict water-table scenarios in a Guarani Aquifer System outcrop area, Brazil

    Science.gov (United States)

    Manzione, Rodrigo L.; Wendland, Edson; Tanikawa, Diego H.

    2012-11-01

    Stochastic methods based on time-series modeling combined with geostatistics can be useful tools to describe the variability of water-table levels in time and space and to account for uncertainty. Monitoring water-level networks can give information about the dynamic of the aquifer domain in both dimensions. Time-series modeling is an elegant way to treat monitoring data without the complexity of physical mechanistic models. Time-series model predictions can be interpolated spatially, with the spatial differences in water-table dynamics determined by the spatial variation in the system properties and the temporal variation driven by the dynamics of the inputs into the system. An integration of stochastic methods is presented, based on time-series modeling and geostatistics as a framework to predict water levels for decision making in groundwater management and land-use planning. The methodology is applied in a case study in a Guarani Aquifer System (GAS) outcrop area located in the southeastern part of Brazil. Communication of results in a clear and understandable form, via simulated scenarios, is discussed as an alternative, when translating scientific knowledge into applications of stochastic hydrogeology in large aquifers with limited monitoring network coverage like the GAS.

  13. Effects of leaf area index on the coupling between water table, land surface energy fluxes, and planetary boundary layer at the regional scale

    Science.gov (United States)

    Lu, Y.; Rihani, J.; Langensiepen, M.; Simmer, C.

    2013-12-01

    Vegetation plays an important role in the exchange of moisture and energy at the land surface. Previous studies indicate that vegetation increases the complexity of the feedbacks between the atmosphere and subsurface through processes such as interception, root water uptake, leaf surface evaporation, and transpiration. Vegetation cover can affect not only the interaction between water table depth and energy fluxes, but also the development of the planetary boundary layer. Leaf Area Index (LAI) is shown to be a major factor influencing these interactions. In this work, we investigate the sensitivity of water table, surface energy fluxes, and atmospheric boundary layer interactions to LAI as a model input. We particularly focus on the role LAI plays on the location and extent of transition zones of strongest coupling and how this role changes over seasonal timescales for a real catchment. The Terrestrial System Modelling Platform (TerrSysMP), developed within the Transregional Collaborative Research Centre 32 (TR32), is used in this study. TerrSysMP consists of the variably saturated groundwater model ParFlow, the land surface model Community Land Model (CLM), and the regional climate and weather forecast model COSMO (COnsortium for Small-scale Modeling). The sensitivity analysis is performed over a range of LAI values for different vegetation types as extracted from the Moderate Resolution Imaging Spectroradiometer (MODIS) dataset for the Rur catchment in Germany. In the first part of this work, effects of vegetation structure on land surface energy fluxes and their connection to water table dynamics are studied using the stand-alone CLM and the coupled subsurface-surface components of TerrSysMP (ParFlow-CLM), respectively. The interconnection between LAI and transition zones of strongest coupling are investigated and analyzed through a subsequent set of subsurface-surface-atmosphere coupled simulations implementing the full TerrSysMP model system.

  14. A Country-Specific Water Consumption Inventory Considering International Trade in Asian Countries Using a Multi-Regional Input-Output Table

    Directory of Open Access Journals (Sweden)

    Yuya Ono

    2017-08-01

    Full Text Available Interest in the impacts of water use in the life cycle of products and services are increasing among various stakeholders. The water footprint is a tool to identify critical and effective points for reducing the impact of water use through the entire life cycle of products, services, and organizations. The purpose of this study was to develop a water consumption inventory database that focused on identifying of Asian water consumption using an input-output (IO framework. An Asia International Input-Output table (AIIO was applied in this study. The amount of water consumption required for agricultural products was estimated by modeling; for other sectors it was estimated from statistical reports. The intensities of direct water consumption in each sector were calculated by dividing the amount of water consumption by the domestic production. Based on the IO analysis using Leontief’s inverse matrix, the intensities of water consumption from cradle to gate were estimated for all goods and services. There was high intensity of water consumption in the primary industry sectors, together with a high dependency on rainwater as an input water source. The water consumption intensities generally showed a larger reduction in secondary sectors, in comparison with the tertiary sectors, due to the use of recycled water. There were differences between this study and previous studies due to the use of site-specific production data and the temporal resolution of crop production. By considering site-specific conditions, it is expected that the dataset developed here can be used for estimating the water footprint of products, services, and organizations in nine countries (Japan, South Korea, China, Taiwan, Thailand, the Philippines, Malaysia, Singapore, Indonesia, and USA.

  15. The disappearing Environmental Kuznets Curve: a study of water quality in the Lower Mekong Basin (LMB).

    Science.gov (United States)

    Wong, Yoon Loong Andrew; Lewis, Lynne

    2013-12-15

    The literature is flush with articles focused on estimating the Environmental Kuznets Curve (EKC) for various pollutants and various locations. Most studies have utilized air pollution variables; far fewer have utilized water quality variables, all with mixed results. We suspect that mixed evidence of the EKC stems from model and error specification. We analyze annual data for four water quality indicators, three of them previously unstudied - total phosphorus (TOTP), dissolved oxygen (DO), ammonium (NH4) and nitrites (NO2) - from the Lower Mekong Basin region to determine whether an Environmental Kuznets Curve (EKC) is evident for a transboundary river in a developing country and whether that curve is dependent on model specification and/or pollutant. We build upon previous studies by correcting for the problems of heteroskedasticity, serial correlation and cross-sectional dependence. Unlike multi-country EKC studies, we mitigate for potential distortion from pooling data across geographically heterogeneous locations by analyzing data drawn from proximate locations within a specific international river basin in Southeast Asia. We also attempt to identify vital socioeconomic determinants of water pollution by including a broad list of explanatory variables alongside the income term. Finally, we attempt to shed light on the pollution-income relationship as it pertains to trans-boundary water pollution by examining data from an international river system. We do not find consistent evidence of an EKC for any of the 4 pollutant indicators in this study, but find the results are entirely dependent on model and error specification as well as pollutant. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Litter type affects the activity of aerobic decomposers in a boreal peatland more than site nutrient and water table regimes

    Directory of Open Access Journals (Sweden)

    P. Straková

    2011-09-01

    Full Text Available Peatlands are carbon (C storage ecosystems sustained by a high water table (WT. High WT creates anoxic conditions that suppress the activity of aerobic decomposers and provide conditions for peat accumulation. Peatland function can be dramatically affected by WT drawdown caused by climate and/or land-use change. Aerobic decomposers are directly affected by WT drawdown through environmental factors such as increased oxygenation and nutrient availability. Additionally, they are indirectly affected via changes in plant community composition and litter quality. We studied the relative importance of direct and indirect effects of WT drawdown on aerobic decomposer activity in plant litter at two stages of decomposition (incubated in the field for 1 or 2 years. We did this by profiling 11 extracellular enzymes involved in the mineralization of organic C, nitrogen (N, phosphorus (P and sulphur. Our study sites represented a three-stage chronosequence from pristine to short-term (years and long-term (decades WT drawdown conditions under two nutrient regimes (bog and fen. The litter types included reflected the prevalent vegetation: Sphagnum mosses, graminoids, shrubs and trees.

    Litter type was the main factor shaping microbial activity patterns and explained about 30 % of the variation in enzyme activities and activity allocation. Overall, enzyme activities were higher in vascular plant litters compared to Sphagnum litters, and the allocation of enzyme activities towards C or nutrient acquisition was related to the initial litter quality (chemical composition. Direct effects of WT regime, site nutrient regime and litter decomposition stage (length of incubation period summed to only about 40 % of the litter type effect. WT regime alone explained about 5 % of the variation in enzyme activities and activity allocation. Generally, enzyme activity increased following the long-term WT drawdown and the activity allocation turned from P

  17. Litter type affects the activity of aerobic decomposers in a boreal peatland more than site nutrient and water table regimes

    Science.gov (United States)

    Straková, P.; Niemi, R. M.; Freeman, C.; Peltoniemi, K.; Toberman, H.; Heiskanen, I.; Fritze, H.; Laiho, R.

    2011-09-01

    Peatlands are carbon (C) storage ecosystems sustained by a high water table (WT). High WT creates anoxic conditions that suppress the activity of aerobic decomposers and provide conditions for peat accumulation. Peatland function can be dramatically affected by WT drawdown caused by climate and/or land-use change. Aerobic decomposers are directly affected by WT drawdown through environmental factors such as increased oxygenation and nutrient availability. Additionally, they are indirectly affected via changes in plant community composition and litter quality. We studied the relative importance of direct and indirect effects of WT drawdown on aerobic decomposer activity in plant litter at two stages of decomposition (incubated in the field for 1 or 2 years). We did this by profiling 11 extracellular enzymes involved in the mineralization of organic C, nitrogen (N), phosphorus (P) and sulphur. Our study sites represented a three-stage chronosequence from pristine to short-term (years) and long-term (decades) WT drawdown conditions under two nutrient regimes (bog and fen). The litter types included reflected the prevalent vegetation: Sphagnum mosses, graminoids, shrubs and trees. Litter type was the main factor shaping microbial activity patterns and explained about 30 % of the variation in enzyme activities and activity allocation. Overall, enzyme activities were higher in vascular plant litters compared to Sphagnum litters, and the allocation of enzyme activities towards C or nutrient acquisition was related to the initial litter quality (chemical composition). Direct effects of WT regime, site nutrient regime and litter decomposition stage (length of incubation period) summed to only about 40 % of the litter type effect. WT regime alone explained about 5 % of the variation in enzyme activities and activity allocation. Generally, enzyme activity increased following the long-term WT drawdown and the activity allocation turned from P and N acquisition towards C

  18. Hydrographs Showing Ground-Water Level Changes for Selected Wells in the Lower Skagit River Basin, Washington

    Science.gov (United States)

    Fasser, E.T.; Julich, R.J.

    2009-01-01

    Hydrographs for selected wells in the Lower Skagit River basin, Washington, are presented in an interactive web-based map to illustrate monthly and seasonal changes in ground-water levels in the study area. Ground-water level data and well information were collected by the U.S. Geological Survey using standard techniques and were stored in the USGS National Water Information System (NWIS), Ground-Water Site-Inventory (GWSI) System.

  19. Metabolic rates are significantly lower in abyssal Holothuroidea than in shallow-water Holothuroidea

    Science.gov (United States)

    van Oevelen, Dick

    2018-01-01

    Recent analyses of metabolic rates in fishes, echinoderms, crustaceans and cephalopods have concluded that bathymetric declines in temperature- and mass-normalized metabolic rate do not result from resource-limitation (e.g. oxygen or food/chemical energy), decreasing temperature or increasing hydrostatic pressure. Instead, based on contrasting bathymetric patterns reported in the metabolic rates of visual and non-visual taxa, declining metabolic rate with depth is proposed to result from relaxation of selection for high locomotory capacity in visual predators as light diminishes. Here, we present metabolic rates of Holothuroidea, a non-visual benthic and benthopelagic echinoderm class, determined in situ at abyssal depths (greater than 4000 m depth). Mean temperature- and mass-normalized metabolic rate did not differ significantly between shallow-water (less than 200 m depth) and bathyal (200–4000 m depth) holothurians, but was significantly lower in abyssal (greater than 4000 m depth) holothurians than in shallow-water holothurians. These results support the dominance of the visual interactions hypothesis at bathyal depths, but indicate that ecological or evolutionary pressures other than biotic visual interactions contribute to bathymetric variation in holothurian metabolic rates. Multiple nonlinear regression assuming power or exponential models indicates that in situ hydrostatic pressure and/or food/chemical energy availability are responsible for variation in holothurian metabolic rates. Consequently, these results have implications for modelling deep-sea energetics and processes. PMID:29892403

  20. Food nanotechnology: water is the key to lowering the energy density of processed foods.

    Science.gov (United States)

    Robson, A A

    2011-01-01

    It is crucial that emergent technologies create foods that help prevent the causal mechanisms of the diet induced disease epidemic. Food nanotechnology could create modem convenience foods that mimic and improve on the nutritional value of the most nutritious cooked wild foods for humans. Structuring a solid processed food similar to a celery stalk using self-assembled, water-filled, edible nanocells or nanotubes would substantially lower its energy density (Food technologists could harness the natural turgor force to produce a firm chocolate bar, biscuit or breakfast cereal with a good bite, without altering the appearance or taste of the product. Water carries flavour with few calories, and taste sensation per mouthful could be improved by processing food on the nanoscale to increase the surface area that is in contact with taste and smell receptors. The bioavailable nutrient content (including cofactors) of processed foods could be increased by existing bioactive nanoencapsulation. This would allow people to continue to consume modern convenience food on a mass scale, while simultaneously and significantly increasing nutrient intake and reducing energy intake per day. Thus, helping to reduce mental ill health, obesity and other postprandial insults.

  1. Biochars made from agro-industrial by-products remove chlorine and lower water toxicity

    Science.gov (United States)

    Tzachristas, Andreas; Xirou, Maria; Manariotis, Ioannis D.; Dailianis, Stefanos; Karapanagioti, Hrissi K.

    2016-04-01

    .5 mg/g. For the two commercial activated carbons, removal efficiencies were 11.4 ± 0.2 mg/g. The column experiment also showed positive results; no breakthrough has been observed after 1L of chlorine solution has passed through a column packed with 4 g of biochar made from the pyrolysis of grape seeds. Toxicity tests were also performed with the chlorine solution before and after passing through this column. The toxicity of the solution decreased after passing through the column packed with biochar suggesting that no toxic compounds are formed during the removal of chlorine by the biochar. The overall idea of this study is the sustainable use of the solid by-products of a food industry or producer to treat water or treated wastewater in order to enhance its quality and lower its toxicity. American Water Works Association (AWWA) 1990 Water quality and treatment, a handbook of community water supplies, Fourth edition.

  2. Seasonal use of shallow water habitat in the Lower Snake River reservoirs by juvenile fall Chinook salmon

    Science.gov (United States)

    Tiffan, Kenneth F.; Connor, William P.

    2012-01-01

    The U.S. Army Corps of Engineers (COE) is preparing a long term management plan for sediments that affect the authorized project purposes of the Lower Granite, Little Goose, Lower Monumental, and Ice Harbor reservoirs (hereafter, the lower Snake River reservoirs), and the area from the mouth of the Snake River to Ice Harbor Dam. We conducted a study from spring 2010 through winter 2011 to describe the habitat use by juvenile Chinook salmon within a selected group of shallow water habitat complexes (spoils to create shallow water habitat, (2) provide evidence for shallow water habitat use by natural subyearlings, (3) provide evidence against large-scale use of shallow water habitat by reservoir-type juveniles, (4) suggest that the depth criterion for defining shallow water habitat (i.e., food web, and intra-specific competition would help to better inform the long-term management plan.

  3. SURFACE WATER POLLUTION WITH HEAVY METALS IN THE LOWER CATCHMENT OF JIU RIVER BASIN, ACCORDING TO THE WATER FRAMEWORK DIRECTIVE (2000/60/EC

    Directory of Open Access Journals (Sweden)

    ADINA SANDA ŞERBAN

    2011-03-01

    Full Text Available Surface water pollution with heavy metals in the lower catchment of Jiu river basin, according to the Water Framework Directive (2000/60/EC. The Water Framework Directive establishes a single transparent, effective and coherent water policy by defining a strategy to combat pollution by requiring specific action programs.Chemical pollution of surface water presents a threat to the aquatic environment with acute and chronic toxicity to aquatic organisms, accumulation in the ecosystem and losses of habitats and biodiversity, as well as a threat to human health (art.1 from Directive 2008/105/EC regarding the environmental quality standards for water policy.The purpose of this study is to evaluate the chemical status for surface water bodies in the lower catchment of Jiu river basin. The assessment was made taking into account the water impact of four heavy metals: cadmium (Cd, nickel (Ni, mercury (Hg and lead (Pb.

  4. Dynamics of Soil Water Evaporation during Soil Drying in the Presence of a Shallow Water Table: Laboratory Experiment and Numerical Analysis

    Science.gov (United States)

    Han, J.; Lin, J.; Liu, P.; Li, W.

    2017-12-01

    Evaporation from a porous medium plays a key role in hydrological, agricultural, environmental, and engineering applications. Laboratory and numerical experiments were conducted to investigate the evolution of soil water evaporation during a continuous drying event. Simulated soil water contents and temperatures by the calibrated model well reproduced measured values at different depths. Results show that the evaporative drying process could be divided into three stages, beginning with a relatively high evaporation rate during stage 1, followed by a lower rate during transient stage and stage 2, and finally maintaining a very low and constant rate during stage 3. The condensation zone was located immediately below the evaporation zone in the profile. Both peaks of evaporation and condensation rate increased rapidly during stage 1 and transition stage, decreased during stage 2, and maintained constant during stage 3. The width of evaporation zone kept a continuous increase during stages 1 and 2 and maintained a nearly constant value of 0.68 cm during stage 3. When the evaporation zone totally moved into the subsurface, a dry surface layer (DSL) formed above the evaporation zone at the end of stage 2. The width of DSL also presented a continuous increase during stage 2 and kept a constant value of 0.71 cm during stage 3. Although the magnitude of condensation zone was much smaller than that for the evaporation zone, the importance of the contribution of condensation zone to soil water dynamics should not be underestimated. Results from our experiment and numerical simulation show that this condensation process resulted in an unexpected and apparent water content increase in the middle of vadose zone profile.

  5. Water assessment for the Lower Colorado River region-emerging energy technology development

    Science.gov (United States)

    1981-08-01

    Water supply availability for two hypothetical levels of emerging energy technology development are assessed. The water and related land resources implications of such hypothetical developments are evaluated. Water requirement, the effects on water quality, costs of water supplies, costs of disposal of wastewaters, and the environmental, economic and social impacts are determined, providing information for the development of non-nuclear energy research.

  6. Spatial Pattern of Populus euphratica Forest Change as Affected by Water Conveyance in the Lower Tarim River

    Directory of Open Access Journals (Sweden)

    Shuhong Peng

    2014-01-01

    Full Text Available To restore declining species, including Populus euphratica and other riparian communities, in the river ecosystem of the lower Tarim River, the ecological water conveyance project (EWCP, as a part of an integrated water resource management plan, was implemented in 2000. The EWCP aims to schedule and manage the water resources in the upper reaches and transfer water to the lower reaches by a series of intermittent water deliveries. The delivered water flows along a modified river channel and nourishes riparian communities by river overflow flooding. Since it began, it has caused a fierce debate over the response of riparian vegetation to the water conveyance scheme. This study focuses on the lower Tarim River, where Populus euphratica forests have undergone watering, due to the EWCP. Twelve Landsat sensor images and one IKONOS satellite imagery acquired between 1999 and 2009 were used to monitor the change in Populus euphratica forests. Bi-temporal change detection and temporal trajectory analysis were employed to represent the spatial pattern of the forest change. Field investigations were used to analyze the driving forces behind forest change from the perspectives of anthropogenic activities and natural forces. The results showed that Populus euphratica forest have been declining in area, which implies that ecological risks have been increased during the watering process. However, forests areas have increased in the regions where the water supply is abundant, and vice versa.

  7. Lower Colorado River GRP Drinking Water Wells, Arizona, 2012, Arizona Department of Environmental Quality

    Data.gov (United States)

    U.S. Environmental Protection Agency — The term public water system refers to any water system that has 15 or more service connections (hook-ups) or serves 25 or more people. Water systems that serve less...

  8. Physico-chemical characteristics of the ground water table after monsoon: a case study at central Travancore in Kerala

    Directory of Open Access Journals (Sweden)

    Sankar S Vishnu

    2014-05-01

    Full Text Available Water quality plays an important role in maintaining plant and animal life. Lack of good quality drinking water and water for sanitation cause health problems. Water quality characteristics arise from a group of physical, chemical and biological factors. The dynamic balance of the aquatic system can be destroyed by human activities resulting in water pollution.Well water has traditionally considered as a safe resource of water for consumption without treatment and extensively used for individual water supply in rural and many urban areas.In this paper a preliminary analysis is done to explore the water quality of selected wells in order to correlate the effect of pollution on water quality at these locations. Water samples are collected from different regions of Vazhappally area located on central travancore of Kerala. These sites are important because people depend only on well water for drinking purpose. The samples are collected from ten locations and analyzed for chemical parameters such as pH, conductivity, salinity, turbidity, acidity, alkainity, hardness, total phosphates, dissolved oxygen, biological oxygen demand, total dissolved solids and Iron content. Samples are also analysed for coliform bacteria which cause pathogenic diseases. Remarkable differences are observed mainly in biological oxygen demand, acidity and hardness. Finally, an attempt has been done to correlate the observed chemical parameters and the waterquality standards. DOI: http://dx.doi.org/10.3126/ije.v3i2.10501 International Journal of the Environment Vol.3(2 2014: 20-27

  9. Acute lower extremity ischaemia

    African Journals Online (AJOL)

    Acute lower extremity ischaemia. Acute lower limb ischaemia is a surgical emergency. ... is ~1.5 cases per 10 000 persons per year. Acute ischaemia ... Table 2. Clinical features discriminating embolic from thrombotic ALEXI. Clinical features.

  10. Characterization of Surface Water and Groundwater Quality in the Lower Tano River Basin Using Statistical and Isotopic Approach.

    Science.gov (United States)

    Edjah, Adwoba; Stenni, Barbara; Cozzi, Giulio; Turetta, Clara; Dreossi, Giuliano; Tetteh Akiti, Thomas; Yidana, Sandow

    2017-04-01

    Adwoba Kua- Manza Edjaha, Barbara Stennib,c,Giuliano Dreossib, Giulio Cozzic, Clara Turetta c,T.T Akitid ,Sandow Yidanae a,eDepartment of Earth Science, University of Ghana Legon, Ghana West Africa bDepartment of Enviromental Sciences, Informatics and Statistics, Ca Foscari University of Venice, Italy cInstitute for the Dynamics of Environmental Processes, CNR, Venice, Italy dDepartment of Nuclear Application and Techniques, Graduate School of Nuclear and Allied Sciences University of Ghana Legon This research is part of a PhD research work "Hydrogeological Assessment of the Lower Tano river basin for sustainable economic usage, Ghana, West - Africa". In this study, the researcher investigated surface water and groundwater quality in the Lower Tano river basin. This assessment was based on some selected sampling sites associated with mining activities, and the development of oil and gas. Statistical approach was applied to characterize the quality of surface water and groundwater. Also, water stable isotopes, which is a natural tracer of the hydrological cycle was used to investigate the origin of groundwater recharge in the basin. The study revealed that Pb and Ni values of the surface water and groundwater samples exceeded the WHO standards for drinking water. In addition, water quality index (WQI), based on physicochemical parameters(EC, TDS, pH) and major ions(Ca2+, Na+, Mg2+, HCO3-,NO3-, CL-, SO42-, K+) exhibited good quality water for 60% of the sampled surface water and groundwater. Other statistical techniques, such as Heavy metal pollution index (HPI), degree of contamination (Cd), and heavy metal evaluation index (HEI), based on trace element parameters in the water samples, reveal that 90% of the surface water and groundwater samples belong to high level of pollution. Principal component analysis (PCA) also suggests that the water quality in the basin is likely affected by rock - water interaction and anthropogenic activities (sea water intrusion). This

  11. Investigation of the coolability of a continuous mass of relocated debris to a water-filled lower plenum. Technical report

    International Nuclear Information System (INIS)

    Rempe, J.L.; Wolf, J.R.; Chavez, S.A.; Condie, K.G.; Hagrman, D.L.; Carmack, W.J.

    1994-09-01

    This report documents work performed to support the development of an analytical and experimental program to investigate the coolability of a continuous mass of debris that relocates to a water-filled lower plenum. The objective of this program is to provide an adequate data base for developing and validating a model to predict the coolability of a continuous mass of debris relocating to a water-filled lower plenum. The model must address higher pressure scenarios, such as the TMI-2 accident, and lower pressure scenarios, which recent calculations indicate are more likely for most operating LWR plants. The model must also address a range of possible debris compositions

  12. [Spatiotemporal variation of Populus euphratica's radial increment at lower reaches of Tarim River after ecological water transfer].

    Science.gov (United States)

    An, Hong-Yan; Xu, Hai-Liang; Ye, Mao; Yu, Pu-Ji; Gong, Jun-Jun

    2011-01-01

    Taking the Populus euphratica at lower reaches of Tarim River as test object, and by the methods of tree dendrohydrology, this paper studied the spatiotemporal variation of P. euphratic' s branch radial increment after ecological water transfer. There was a significant difference in the mean radial increment before and after ecological water transfer. The radial increment after the eco-water transfer was increased by 125%, compared with that before the water transfer. During the period of ecological water transfer, the radial increment was increased with increasing water transfer quantity, and there was a positive correlation between the annual radial increment and the total water transfer quantity (R2 = 0.394), suggesting that the radial increment of P. euphratica could be taken as the performance indicator of ecological water transfer. After the ecological water transfer, the radial increment changed greatly with the distance to the River, i.e. , decreased significantly along with the increasing distance to the River (P = 0.007). The P. euphratic' s branch radial increment also differed with stream segment (P = 0.017 ), i.e. , the closer to the head-water point (Daxihaizi Reservoir), the greater the branch radial increment. It was considered that the limited effect of the current ecological water transfer could scarcely change the continually deteriorating situation of the lower reaches of Tarim River.

  13. On the formation of sulfuric acid-water particles via homogeneous nucleation in the lower troposphere

    Energy Technology Data Exchange (ETDEWEB)

    Kerminen, V.M.

    1995-12-31

    Production of new sulfur derived particles via homogeneous nucleation between sulfuric acid and water vapors, and other related aerosol processes taking place in a variety of tropospheric environments, were studied using theoretical and model approaches. For nucleation to occur in the lower troposphere, cool and humid conditions combined with relatively strong solar radiation were usually required. Regardless of the system concerned, production of nuclei was found to be favored also by high SO{sub 2}(g) to fine particulate matter ratios. Urban post-fog situations, which are encountered commonly during severe air pollution episodes, were shown to favor new particle production considerably above the corresponding `background` conditions. A simple procedure for evaluating post-fog nucleation probabilities from routinely obtained data was developed and applied to real aerosol systems. Nucleation in the remote marine environment, which is an essential phenomenon in linking natural sulfur emissions to global climate change, was studied from a dynamic point of view. It was demonstrated that new particle production occurs more often in association with relative humidity transitions typical for many boundary layer processes than under averaged or steady conditions of the kind assumed explicitly in most earlier model studies. Power plant plumes were shown to be a particularly significant source of atmospheric nuclei, due primarily to their frequently high SO{sub 2}-to-particulate matter ratios. Factors affecting the probability of nucleation during plume dispersion were examined in detail, and finally, strategies for the control of in-plume particle production were analyzed. (author)

  14. Modeling the potential impacts of climate change on the water table level of selected forested wetlands in the southeastern United States

    Directory of Open Access Journals (Sweden)

    J. Zhu

    2017-12-01

    Full Text Available The southeastern United States hosts extensive forested wetlands, providing ecosystem services including carbon sequestration, water quality improvement, groundwater recharge, and wildlife habitat. However, these wetland ecosystems are dependent on local climate and hydrology, and are therefore at risk due to climate and land use change. This study develops site-specific empirical hydrologic models for five forested wetlands with different characteristics by analyzing long-term observed meteorological and hydrological data. These wetlands represent typical cypress ponds/swamps, Carolina bays, pine flatwoods, drained pocosins, and natural bottomland hardwood ecosystems. The validated empirical models are then applied at each wetland to predict future water table changes using climate projections from 20 general circulation models (GCMs participating in Coupled Model Inter-comparison Project 5 (CMIP5 under the Representative Concentration Pathways (RCPs 4.5 and 8.5 scenarios. We show that combined future changes in precipitation and potential evapotranspiration would significantly alter wetland hydrology including groundwater dynamics by the end of the 21st century. Compared to the historical period, all five wetlands are predicted to become drier over time. The mean water table depth is predicted to drop by 4 to 22 cm in response to the decrease in water availability (i.e., precipitation minus potential evapotranspiration by the year 2100. Among the five examined wetlands, the depressional wetland in hot and humid Florida appears to be most vulnerable to future climate change. This study provides quantitative information on the potential magnitude of wetland hydrological response to future climate change in typical forested wetlands in the southeastern US.

  15. Modeling the potential impacts of climate change on the water table level of selected forested wetlands in the southeastern United States

    Science.gov (United States)

    Zhu, Jie; Sun, Ge; Li, Wenhong; Zhang, Yu; Miao, Guofang; Noormets, Asko; McNulty, Steve G.; King, John S.; Kumar, Mukesh; Wang, Xuan

    2017-12-01

    The southeastern United States hosts extensive forested wetlands, providing ecosystem services including carbon sequestration, water quality improvement, groundwater recharge, and wildlife habitat. However, these wetland ecosystems are dependent on local climate and hydrology, and are therefore at risk due to climate and land use change. This study develops site-specific empirical hydrologic models for five forested wetlands with different characteristics by analyzing long-term observed meteorological and hydrological data. These wetlands represent typical cypress ponds/swamps, Carolina bays, pine flatwoods, drained pocosins, and natural bottomland hardwood ecosystems. The validated empirical models are then applied at each wetland to predict future water table changes using climate projections from 20 general circulation models (GCMs) participating in Coupled Model Inter-comparison Project 5 (CMIP5) under the Representative Concentration Pathways (RCPs) 4.5 and 8.5 scenarios. We show that combined future changes in precipitation and potential evapotranspiration would significantly alter wetland hydrology including groundwater dynamics by the end of the 21st century. Compared to the historical period, all five wetlands are predicted to become drier over time. The mean water table depth is predicted to drop by 4 to 22 cm in response to the decrease in water availability (i.e., precipitation minus potential evapotranspiration) by the year 2100. Among the five examined wetlands, the depressional wetland in hot and humid Florida appears to be most vulnerable to future climate change. This study provides quantitative information on the potential magnitude of wetland hydrological response to future climate change in typical forested wetlands in the southeastern US.

  16. Geology, Water, and Wind in the Lower Helmand Basin, Southern Afghanistan

    Science.gov (United States)

    Whitney, John W.

    2006-01-01

    earth' by 19th century visitors. During dry years, large plumes of dust originating from Sistan are recorded by weather satellites. The Helmand River drains about 40 percent of Afghanistan and receives most of its moisture from melting snow and spring storms. Similar to many desert streams, the Helmand and its main tributary, the Arghandab River, are characterized by large fluctuations in monthly and annual discharges. Water from the Helmand accumulates in several hamuns (shallow lakes) in the Sistan depression. The wetlands surrounding these hamuns are the largest in western Asia and are directly affected by droughts and floods on the Helmand. Average annual discharge on the Helmand is about 6.12 million megaliters (million cubic meters), and the annual discharge varies by a factor of five. In 2005, the region was just beginning to recover from the longest drought (1998-2005) of record back to 1830. Annual peak discharges range from less than 80 cubic meters per second in 1971 to nearly 19,000 cubic meters per second in 1885. Large floods fill each hamun to overflowing to create one large lake that overflows into the normally dry Gaud-i Zirreh basin. The interaction of flooding, active subsidence, and wind erosion causes frequent channel changes on the Helmand delta. A major development effort on the Helmand River was initiated after World War II with substantial aid from the United States. Two dams and several major canals were completed in the 1950s; however, poor drainage conditions on the newly prepared agricultural fields caused extensive waterlogging and salinization. New drains were installed and improved agricultural methods were implemented in the 1970s, and some lands became more productive. Since 1980, Afghanistan has endured almost constant war and civil and political strife. In 2005, the country was on a path to rebuild much of its technical infrastructure. Revitalization of agricultural lands in the lower Helmand Basin and improved managem

  17. Development of water quality objectives and management systems for the lower Athabasca River in the oil sands area

    International Nuclear Information System (INIS)

    Noton, L.; McEachern, P.

    2004-01-01

    This paper addressed environmental concerns related to the increased oil sands activity along the lower Athabasca River in northeastern Alberta. The concerns include potential effects on water quality of the river even though wastewaters do not currently reach the Athabasca River, nor do they have any significant effects. However, as the industry expands, there is concern that releases of wastewater may increase significantly. A multi-stakeholder group called the Cumulative Environmental Management Association (CEMA) has addressed some of these environmental management issues in the Athabasca area by establishing a water quality task group that examines water quality protection and management activities. The task group intends to develop and recommend water quality objectives and management options on the lower Athabasca River. Their 4 part process includes: (1) defining the problem, (2) setting goals, (3) measuring performance, and (4) managing and adapting to potential impacts. The group has identified and defined about 35 water quality variables of potential concern. It has also identified the uses of water it wants to protect and intends to prevent the degradation of water quality. A plan for developing site specific water quality objectives has been established following a review of water quality guidelines. Performance will be measured using water quality models that simulate full development scenarios. The modelling work will be instrumental in designing management schemes for any potential impacts

  18. Coupled thermo-mechanical creep analysis for boiling water reactor pressure vessel lower head

    International Nuclear Information System (INIS)

    Villanueva, Walter; Tran, Chi-Thanh; Kudinov, Pavel

    2012-01-01

    Highlights: ► We consider a severe accident in a BWR with melt pool formation in the lower head. ► We study the influence of pool depth on vessel failure mode with creep analysis. ► There are two modes of failure; ballooning of vessel bottom and a localized creep. ► External vessel cooling can suppress creep and subsequently prevent vessel failure. - Abstract: In this paper we consider a hypothetical severe accident in a Nordic-type boiling water reactor (BWR) at the stage of relocation of molten core materials to the lower head and subsequent debris bed and then melt pool formation. Nordic BWRs rely on reactor cavity flooding as a means for ex-vessel melt coolability and ultimate termination of the accident progression. However, different modes of vessel failure may result in different regimes of melt release from the vessel, which determine initial conditions for melt coolant interaction and eventually coolability of the debris bed. The goal of this study is to define if retention of decay-heated melt inside the reactor pressure vessel is possible and investigate modes of the vessel wall failure otherwise. The mode of failure is contingent upon the ultimate mechanical strength of the vessel structures under given mechanical and thermal loads and applied cooling measures. The influence of pool depth and respective transient thermal loads on the reactor vessel failure mode is studied with coupled thermo-mechanical creep analysis. Efficacy of control rod guide tube (CRGT) cooling and external vessel wall cooling as potential severe accident management measures is investigated. First, only CRGT cooling is considered in simulations revealing two different modes of vessel failure: (i) a ‘ballooning’ of the vessel bottom and (ii) a ‘localized creep’ concentrated within the vicinity of the top surface of the melt pool. Second, possibility of in-vessel retention with CRGT and external vessel cooling is investigated. We found that the external vessel

  19. Lower Colorado River GRP Public Water System Intakes, Nevada, 2012, Nevada Division of Environmental Protection Bureau of Safe Drinking Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Public Water System wells, springs an intake locations are collected and maintained by NDEP Bureau of Safe Drinking Water (BSDW). The data is kept in the Safe...

  20. Lower Colorado River GRP Public Water System Springs, Nevada, 2012, Nevada Division of Environmental Protection Bureau of Safe Drinking Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Public Water System wells, springs an intake locations are collected and maintained by NDEP Bureau of Safe Drinking Water (BSDW). The data is kept in the Safe...

  1. Lower Colorado River GRP Public Water System Wells, Nevada, 2012, Nevada Division of Environmental Protection Bureau of Safe Drinking Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Public Water System wells, springs an intake locations are collected and maintained by NDEP Bureau of Safe Drinking Water (BSDW). The data is kept in the Safe...

  2. Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix C: Water Quality

    National Research Council Canada - National Science Library

    2002-01-01

    ... (collectively called the Lower-Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

  3. Efeito de velocidades de rebaixamento do nível freático em diferentes períodos de desenvolvimento da cultura da alface Effect of water table drawdown velocities in different stages of lettuce crop

    Directory of Open Access Journals (Sweden)

    Rafael Mingoti

    2006-03-01

    Full Text Available Através deste trabalho objetivou-se determinar os efeitos do encharcamento do solo nas variáveis fenológicas e na produtividade da cultura da alface, identificar o estádio fenológico em que ocorre a maior diminuição da produtividade e obter uma relação entre a produtividade relativa da cultura e o índice diário de estresse. O delineamento experimental adotado foi inteiramente casualizado, arranjado em esquema fatorial [(3x4+1], com 3 repetições. Os tratamentos consistiram do período de inundação (12, 22 e 32 DAT, de velocidades de rebaixamento do nível freático (30 cm em 24, 48, 72 e 96 horas e uma testemunha, na qual não foi aplicado estresse por elevação do lençol freático. A alface apresentou-se como cultura sensível ao encharcamento; entretanto, não foi possível se definir um valor para o coeficiente de drenagem pois, mesmo com a maior velocidade de rebaixamento testada, ocorreu decréscimo de cerca de 50% da produção. Dentre os três períodos nos quais o estresse causado pela elevação do nível freático foi aplicado, o primeiro foi o que ocasionou maiores perdas. A produtividade das plantas de alface apresentou correlação linear negativa com o índice diário de estresse (IDS.The work had the objectives of determining the effect of water table drawdown velocities on the growth and yield of lettuce crop in a flooded soil, identifying the stage of the crop cycle with the highest reduction in the productivity and obtaining a relation between the crop relative productivity and the daily stress index. The statistical experimental design was completely randomized in factorial scheme [(3 x 4 + 1], with three replications. The water table was lowered at 3 stages of the crop cycle (12, 22 and 32 days after the transplanting, four drawdown velocities (30 cm during 24, 48, 72 and 96 h and a 13 treatment in which stress was not applied with the elevation of the water table. The lettuce presented as a sensible crop to

  4. Towards lower carbon footprint patterns of consumption: The case of drinking water in Italy

    International Nuclear Information System (INIS)

    Botto, S.; Niccolucci, V.; Rugani, B.; Nicolardi, V.; Bastianoni, S.; Gaggi, C.

    2011-01-01

    The effects that individual consumption behaviours have on climate change are explored, focusing on products that satisfy the same need but with different carbon footprints. Two types of drinking water, produced, distributed and consumed in Italy, were compared as a case study: tap water and PET-bottled natural mineral water. The first is the one supplied to the municipality of Siena, while the second is a set of 6 different Italian bottled water brands. The results showed that drinking 1.5 L of tap water instead of PET-bottled water saves 0.34 kg CO 2 eq. Thus, a PET-bottled water consumer (2 L per day) who changes to tap water may prevent 163.50 kg CO 2 eq of greenhouse gas emissions per year. In monetary terms, this translates into a tradable annual verified emission reduction (VER) between US$ 0.20 and 7.67 per drinker. Analysing a mature bottled water market, such as the Italian one, may provide insights into the growing global bottled-water market and its effects on climate change. The environmental and economic benefits of changing drinking water habits are also discussed.

  5. Water-table altitude of the unconfined aquifer, Wood River Valley aquifer system, south-central Idaho, October 2012.

    Data.gov (United States)

    Department of the Interior — Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established...

  6. ANALYSIS OF CHANGES IN WATER CONSUMPTION IN SELECTED CITIES OF LOWER SILESIAN VOIVODSHIP IN 2005-2010

    Directory of Open Access Journals (Sweden)

    Beata Malczewska

    2016-12-01

    Full Text Available The subject of the work is the analysis of changes in water consumption for the years 2005-2010. Analysis have been subjected to the town of Oborniki Śląskie, Bystrzyca Kłodzka and Klodzko. All towns are located at the lower Silesian Voivodeship. They differ by its populations and the development of various economy branches. In this paper we are presenting the changes in the water uptake by user group and the total amount of water pumped into the network. The information about the quantity of water sold by water plants and the size of the losses resulting from leaks and accidents on the water-supply networks are also included.

  7. Retrieval of water vapor vertical distributions in the upper troposphere and the lower stratosphere from SCIAMACHY limb measurements

    OpenAIRE

    Rozanov, A.; Weigel, K.; Bovensmann, H.; Dhomse, S.; Eichmann, K.-U.; Kivi, R.; Rozanov, V.; Vömel, H.; Weber, M.; Burrows, J. P.

    2011-01-01

    This study describes the retrieval of water vapor vertical distributions in the upper troposphere and lower stratosphere (UTLS) altitude range from space-borne observations of the scattered solar light made in limb viewing geometry. First results using measurements from SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY) aboard ENVISAT (Environmental Satellite) are presented here. In previous publications, the retrieval of water vapor vertical ...

  8. SMART - IWRM : Integrated Water Resources Management in the Lower Jordan Rift Valley; Project Report Phase I (KIT Scientific Reports ; 7597)

    OpenAIRE

    Wolf, Leif; Hötzl, Heinz [Hrsg.

    2011-01-01

    This book provides an overview of the large scale Integrated Water Resources Management (IWRM) research program SMART at the Lower Jordan River Basin which aims at local implementation, knowledge & capacity building. The focus of the first phase is placed on decentralised wastewater treatment and reuse, water quality including emerging pollutants, management and modelling of groundwater systems, artificial recharge, socio-economic frameworks, a transboundary database and decision support tools.

  9. Scots pine (Pinus sylvestris L.) based reconstruction of 130 years of water table fluctuations in a peatland and its relevance for moisture variability assessments

    Science.gov (United States)

    Tamkevičiūtė, Marija; Edvardsson, Johannes; Pukienė, Rūtilė; Taminskas, Julius; Stoffel, Markus; Corona, Christophe; Kibirkštis, Gintautas

    2018-03-01

    Continuous water-table (WT) measurements from peatlands are scarce and - if existing at all -very short. Consequently, proxy indicators are critically needed to simulate hydrological changes in peatlands over longer time periods. In this study, we demonstrate that tree-ring width (TRW) records of Scots pine (Pinus sylvestris L.) growing in the Čepkeliai peatland (southern Lithuania) can be used as a proxy to reconstruct hydrological variability in a raised bog environment. A two-step modelling procedure was applied to extend existing measurements and to develop a new and longer peatland WT time series. To this end, we used instrumental WT measurements extending back to 2002, meteorological records, a P-PET (difference between precipitation and potential evapotranspiration) series covering the period 1935-2014, so as to construct a tree-ring based time series of WT fluctuations at the site for the period 1870-2014. Strongest correlations were obtained between average annual WT measured at the bog margin and total P-PET over 7 years (r = 0.923, p runoff since CE 1812 (r = 0.39, p < 0.00001, 1870-2014). We conclude that peatlands can act both as sinks and sources of greenhouse gases in case that hydrological conditions change, but that hydrological lags and complex feedbacks still hamper our understanding of several processes affecting the hydrology and carbon budget in peatlands. We therefore call for the development of further proxy records of water-table variability in peatlands to improve our understanding of peatland responses to climatic changes.

  10. Guided design of heating and cooling mains for lower water and energy consumption and increased efficiency

    CSIR Research Space (South Africa)

    Gololo, V

    2011-01-01

    Full Text Available Water cooling and water heating is an important source of energy consumption, accounting for more than 20% of all energy consumption in manufacturing industry. It is clear that the development of heat recycling schemes and better structural design...

  11. Economic Impact of Water Allocation on Agriculture in the Lower Chattahoochee River Basin

    Science.gov (United States)

    Limaye, Ashutosh S.; Paudel, Krishna P.; Musleh, Fuad; Cruise, James F.; Hatch, L. Upton

    2004-01-01

    The relative value of irrigation water was assessed for three important crops (corn, cotton, and peanuts) grown in the southeastern United States. A decision tool was developed with the objective of allocating limited available water among competing crops in a manner that would maximize the economic returns to the producers. The methodology was developed and tested for a hypothetical farm located in Henry County, Alabama in the Chattahoochee river basin. Crop yield - soil moisture response functions were developed using Monte Carlo simulated data for cotton, corn, and peanuts. A hydrologic model was employed to simulate runoff over the period of observed rainfall the county to provide inflows to storage facilities that could be used as constraints for the optimal allocation of the available water in the face of the uncertainty of future rainfall and runoff. Irrigation decisions were made on a weekly basis during the critical water deficit period in the region. An economic optimization model was employed with the crop responses, and soil moisture functions to determine the optimum amount of water place on each crop subject to the amount of irrigation water availability and climatic uncertainty. The results indicated even small amounts of irrigation could significantly benefit farmers in the region if applied judiciously. A weekly irrigation sequence was developed that maintained the available water on the crops that exhibited the most significant combination of water sensitivity and cash value.

  12. Physiological and morphological effects of high water tables on early growth of giant reed (Arundo donax), elephant grass (Pennisetum purpureum), energycane and sugarcane (Saccharum spp.)

    Energy Technology Data Exchange (ETDEWEB)

    Jennewein, Stephen Peter [Univ. of Florida, Gainesville, FL (United States)

    2013-01-01

    Here, an increasing demand for renewable energy sources has spurred interest in high-biomass crops used for energy production. Species potentially well-suited for biofuel production in the seasonally wet organic Everglades Agricultural Area (EAA) of Florida include giant reed (Arundo donax), elephant grass (Pennisetum Purpureum), energycane (Saccharum spp.), and sugarcane (Saccharum spp.). The objectives in this study were to evaluate the role of fluctuating water tables on the morphology, physiology, and early season growth of these four genotypes. The candidate genotypes were grown in a greenhouse under three water table depths, defined by distance of the water table from the soil surface: two constant water tables (-16 cm and -40 cm) along with a flood cycle (2 weeks of flood to the soil level followed by 2 weeks at -40 cm from the soil level). The genotypes included CP 89-2143 (sugarcane), L 79-1002 (energycane), Merkeron (elephant grass), and wild type (giant reed). The experiment was repeated for plant cane, first ratoon, and successive plant cane crop cycles. Reductions in dry matter yield were observed among genotypes subjected to the -40 cm drained, periodically flooded (40F) water table relative to the -40 cm constant (40C) or -16 cm constant (16C). Plant cane dry weights were reduced by 37% in giant reed, 52% in elephant grass, 42% in energycane, and 34% in sugarcane in the 40F compared to 40C water table treatments. Similarly, in the first ratoon crop dry weights were reduced by 29% in giant reed, 42% in elephant grass, 27% in energycane, and 62% in sugarcane. In plant cane and successive plant cane, average total dry weight was greatest for elephant grass whereas ratoon total dry weight was greatest for energycane. Genotype had more pronounced effects on physiological attributes than water table including the highest stomatal conductance and SPAD values in giant reed, and the highest stalk populations in elephant grass and

  13. Table 1

    African Journals Online (AJOL)

    Schalk Cloete

    Data include 777 birth and 605 weaning records of lambs and 562 ... injudiciously, resulting in wool contamination and the loss of genetic material needed .... stubble lands until green feed became available after autumn and early winter rains. .... Lambs born in 2001 had lower (P < 0.05) weaning weights than those born in ...

  14. Improved flooding tolerance and carbohydrate status of flood-tolerant plant Arundinella anomala at lower water temperature.

    Directory of Open Access Journals (Sweden)

    Xiao Qi Ye

    Full Text Available Operation of the Three Gorges Reservoir (TGR, China imposes a new water fluctuation regime, including a prolonged winter submergence in contrast to the natural short summer flooding of the rivers. The contrasting water temperature regimes may remarkably affect the survival of submerged plants in the TGR. Plant survival in such prolonged flooding might depend on the carbohydrate status of the plants. Therefore, we investigated the effects of water temperature on survival and carbohydrate status in a flood-tolerant plant species and predicted that both survival and carbohydrate status would be improved by lower water temperatures.A growth chamber experiment with controlled water temperature were performed with the flood-tolerant species Arundinella anomala from the TGR region. The plants were submerged (80 cm deep water above soil surface with a constant water temperature at 30°C, 20°C or 10°C. The water temperature effects on survival, plant biomass and carbohydrate content (glucose, fructose and sucrose and starch in the viable and dead tissues were investigated.The results showed that the survival percentage of A.anomala plants was greatly dependent on water temperature. The two-month submergence survival percentage was 100% at 10°C, 40% at 20°C and 0% at 30°C. Decreasing the water temperature led to both later leaf death and slower biomass loss. Temperature decrease also induced less reduction in glucose, fructose and sucrose in the roots and leaves (before decay, p 0.05. Different water temperatures did not alter the carbon pool size in the stems, leaves and whole plants (p > 0.05, but a clear difference was found in the roots (p < 0.05, with a larger pool size at a lower temperature.We concluded that (1 A. anomala is characterized by high flooding tolerance and sustained capability to mobilize carbohydrate pool. (2 The survival percentage and carbohydrate status of submerged A. anomala plants were remarkably improved by lower water

  15. Experimental study on water transport observations of desert riparian forests in the lower reaches of the Tarim River in China.

    Science.gov (United States)

    Chen, Yaning; Li, Weihong; Zhou, Honghua; Chen, Yapeng; XinmingHao; Fu, Aihong; Ma, Jianxin

    2017-06-01

    Studying the water use processes of desert riparian vegetation in arid regions and analyzing the response and adaptation strategies of plants to drought stress are of great significance for developing ecological restoration measures. Based on field monitoring and test analyses of physiological ecological indicators of dominant species (Populus euphratica and Tamarix chinensis) in the desert riparian forest in the lower reaches of the Tarim River, the water relations of P. euphratica and T. chinensis under drought stress are discussed and some water use strategies put forward. The results show that (1) concerning plant water uptake, desert riparian forests depend mainly on groundwater to survive under long-term water stress. (2) Concerning plant water distribution, the survival of P. euphratica and nearby shallow root plants is mainly due to the hydraulic lift and water redistribution of P. euphratica under drought stress. (3) Concerning plant water transport, P. euphratica sustains the survival of competitive and advantageous branches by improving their ability to acquire water while restraining the growth of inferior branches. (4) Concerning plant transpiration, the sap flow curves of daily variations of P. euphratica and T. chinensis were wide-peak sin and narrower-peak respectively. T. chinensis has better environmental adaptability.

  16. Drivers and Effects of Groundwater-Surface Water Interaction in the Karstic Lower Flint River Basin, Southwestern Georgia, USA

    Science.gov (United States)

    Rugel, K.; Golladay, S. W.; Jackson, C. R.; Rasmussen, T. C.; Dowd, J. F.; Mcdowell, R. J.

    2017-12-01

    Groundwater provides the majority of global water resources for domestic and agricultural usage while contributing vital surface water baseflows which support healthy aquatic ecosystems. Understanding the extent and magnitude of hydrologic connectivity between groundwater and surface water components in karst watersheds is essential to the prudent management of these hydraulically-interactive systems. We examined groundwater and surface water connectivity between the Upper Floridan Aquifer (UFA) and streams in the Lower Flint River Basin (LFRB) in southwestern Georgia where development of agricultural irrigation intensified over the past 30 years. An analysis of USGS streamflow data for the pre- and post-irrigation period showed summer baseflows in some Lower Flint River tributaries were reduced by an order of magnitude in the post-irrigation period, reiterating the strong hydraulic connection between these streams and the underlying aquifer. Large and fine-scale monitoring of calcium, nitrate, specific conductance and stable isotopes (δ18O and δD) on 50 km of Ichawaynochaway Creek, a major tributary of the Lower Flint, detected discrete groundwater-surface water flow paths which accounted for 42% of total groundwater contributions in the 50 km study reach. This presentation will highlight a new analysis using the metadata EPA Reach File (1) and comparing stream reach and instream bedrock joint azimuths with stream geochemical results from previous field study. Our findings suggested that reaches with NNW bearing may be more likely to display enhanced groundwater-surface water connectivity. Our results show that local heterogeneity can significantly affect water budgets and quality within these watersheds, making the use of geomorphological stream attributes a valuable tool to water resource management for the prediction and protection of vulnerable regions of hydrologic connectivity in karst catchments.

  17. Fluctuating water table affects gross ecosystem production and gross radiation use efficiency in a sedge-grass marsh

    Czech Academy of Sciences Publication Activity Database

    Dušek, Jiří; Čížková, Hana; Stellner, Stanislav; Czerný, Radek; Květ, Jan

    2012-01-01

    Roč. 692, č. 1 (2012), s. 57-66 ISSN 0018-8158 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŽP(CZ) SP/2D1/93/07; GA MŠk OC08021 Institutional research plan: CEZ:AV0Z60870520 Keywords : Wetland * fen * carbon * water level * Carex acuta L. * Eddy covariance Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.985, year: 2012

  18. Lower Colorado River GRP Dams and Water Retention Structures, Arizona, 2012, Arizona Department of Environmental Quality

    Data.gov (United States)

    U.S. Environmental Protection Agency — Location of dams and water retention structures as compiled from multiple sources by the Arizona Department of Environmental Quality (ADEQ). The data are "sensitive"...

  19. Water

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available Water scarcity is without a doubt on of the greatest threats to the human species and has all the potential to destabilise world peace. Falling water tables are a new phenomenon. Up until the development of steam and electric motors, deep groudwater...

  20. Efecto del agua aplicada en las relaciones hídricas y productividad de la vid 'Crimson Seedless' Effect of applied water on water relations and productivity of 'Crimson Seedless' table grapes

    Directory of Open Access Journals (Sweden)

    Raúl Ferreyra

    2006-07-01

    Full Text Available Este estudio fue dirigido para evaluar la relación agua-rendimiento en vid de mesa cv. Crimson y establecer valores críticos para las mediciones del estado hídrico de las plantas. Los estudios de campo se desarrollaron durante tres años, en el Valle de Aconcagua, Chile, a 32º47'S y 70º42'O, en un suelo de textura franco arcillosa. Se proporcionaron a las plantas diferentes cantidades de agua de riego entre 40 y 100% de la evapotranspiración del cultivo (Etc. El potencial hídrico xilemático medido a mediodía (psixmin y la conductancia estomática estuvieron estrechamente relacionados con el déficit de agua impuesto y el rendimiento obtenido. Los rendimientos de la vid disminuyeron respecto al agua aplicada en el rango de los tratamientos estudiados. Sesenta por ciento de restricción de la Etc redujo 22% del rendimiento. Cuando la planta mantuvo psixmin mayor que -0,75 MPa entre cuaja y pinta, la producción y los calibres fueron mayores.This study aimed to evaluate the relationship between water and production in 'Crimson Seedless' table grapes, and to establish threshold values for plants water status. Field experiments were carried out, during a three-year period, in the Aconcagua Valley, Chile, at 32º47'S and 70º42'W, in a clay-loamy textured soil. Different irrigation water amounts were applied, between 40 and 100% crop evapotranspiration (Etc. Stem water potential measured at midday (psixmin and stomatal conductance were closely related to water shortage and yield obtained. Table grape yields decreased in comparison with applied water within the range of studied treatments. Sixty per cent Etc restriction decreased yields in 22%. When plants maintained psixmin greater than -0.75 MPa, between berry set and veraison, yield and berry size were high.

  1. Delineating groundwater/surface water interaction in a karst watershed: Lower Flint River Basin, southwestern Georgia, USA

    Directory of Open Access Journals (Sweden)

    Kathleen Rugel

    2016-03-01

    Full Text Available Study region: Karst watershed in Lower Flint River Basin (LFRB, southwestern Georgia, USA. Study focus: Baseflow discharges in the LFRB have declined for three decades as regional irrigation has increased; yet, the location and nature of connectivity between groundwater and surface water in this karstic region are poorly understood. Because growing water demands will likely be met by further development of regional aquifers, an important management concern is the nature of interactions between groundwater and surface water components under natural and anthropogenic perturbations. We conducted coarse and fine-scale stream sampling on a major tributary of the Lower Flint River (Ichawaynochaway Creek in southwestern Georgia, USA, to identify locations and patterns of enhanced hydrologic connectivity between this stream and the Upper Floridan Aquifer. New hydrological insights for the region: Prior water resource studies in the LFRB were based on regional modeling that neglected local heterogeneities in groundwater/surface water connectivity. Our results demonstrated groundwater inputs were concentrated around five of fifty sampled reaches, evidenced by increases in multiple groundwater indicators at these sites. These five reaches contributed up to 42% of the groundwater detected along the entire 50-km sampling section, with ∼24% entering through one groundwater-dominated tributary, Chickasawhatchee Creek. Intermittent flows occurred in two of these upstream reaches during extreme drought and heavy groundwater pumping, suggesting reach-scale behaviors should be considered in resource management and policy. Keywords: Karst hydrogeology, Hydrologic connectivity, Groundwater/surface water interaction, Upper Floridan Aquifer, Groundwater Irrigation

  2. Pulse radiolysis of liquid water using picosecond electron pulses produced by a table-top terawatt laser system

    International Nuclear Information System (INIS)

    Saleh, Ned; Flippo, Kirk; Nemoto, Koshichi; Umstadter, Donald; Crowell, Robert A.; Jonah, Charles D.; Trifunac, Alexander D.

    2000-01-01

    A laser based electron generator is shown, for the first time, to produce sufficient charge to conduct time resolved investigations of radiation induced chemical events. Electron pulses generated by focussing terawatt laser pulses into a supersonic helium gas jet are used to ionize liquid water. The decay of the hydrated electrons produced by the ionizing electron pulses is monitored with 0.3 μs time resolution. Hydrated electron concentrations as high as 22 μM were generated. The results show that terawatt lasers offer both an alternative to linear accelerators and a means to achieve subpicosecond time resolution for pulse radiolysis studies. (c) 2000 American Institute of Physics

  3. Influence of intermittent water releases on groundwater chemistry at the lower reaches of the Tarim River, China.

    Science.gov (United States)

    Chen, Yong-jin; Chen, Ya-ning; Liu, Jia-zhen; Zhang, Er-xun

    2009-11-01

    Based on the data of the depths and the chemical properties of groundwater, salinity in the soil profile, and the basic information on each delivery of water collected from the years 2000 to 2006, the varied character of groundwater chemistry and related factors were studied. The results confirmed the three stages of the variations in groundwater chemistry influenced by the intermittent water deliveries. The factors that had close relations to the variations in groundwater chemistry were the distances of monitoring wells from the water channel, the depths of the groundwater, water flux in watercourse, and the salinities in soils. The relations between chemical variation and groundwater depths indicated that the water quality was the best with the groundwater varying from 5 to 6 m. In addition, the constructive species in the study area can survive well with the depth of groundwater varying from 5 to 6 m, so the rational depth of groundwater in the lower reaches of the Tarim River should be 5 m or so. The redistribution of salts in the soil profile and its relations to the chemical properties and depths of groundwater revealed the linear water delivery at present combining with surface water supply in proper sections would promote water quality optimized and speed up the pace of ecological restoration in the study area.

  4. Radiation heat transfer in a pressurized water reactor lower head filled with molten corium

    International Nuclear Information System (INIS)

    Šadek, Siniša; Grgić, Davor; Debrecin, Nenad

    2013-01-01

    Highlights: ► We develop radiation heat exchange model for a reactor pressure vessel lower head. ► Model is used during a late in-vessel phase of severe accidents. ► View factors are calculated automatically for a time-dependent enclosure. ► Model is included in the RELAP5/SCDAPSIM computer code. ► Inclusion of heat radiation causes faster heat-up rate of RPV lower head structures. - Abstract: Following a core melt, molten material may slump to the lower head of a reactor pressure vessel (RPV). In that case, some structures like lower parts of fuel elements and a core support plate would remain intact. Since the melt is at high temperature and there are no obstacles between the melt and the supporting plate, the plate is exposed to an intense radiation heating. The radiation heat exchange model of the lower head was developed and applied to a finite element code COUPLE which is a part of the detailed mechanistic code RELAP5/SCDAPSIM. The radiation enclosure consisted of three surfaces: the upper surface of the relocated material, the inner surface of the RPV wall above the relocated material and the lower surface of the core support plate. View factors were calculated for the enclosure geometry that is changing in time because of intermittent accumulation of molten material. The enclosure surfaces were covered by mesh of polygonal areas and view factors were calculated, for each pair of the element areas, by solving the definite integrals using the algorithms for adaptive integrations by means of Gaussian quadrature. Algebraic equations for radiosity and irradiation vectors were solved by LU decomposition and the radiation model was explicitly coupled with the heat conduction model. The results show that there is a possibility of the core support plate failure after being heated up due to radiation heat exchange with the melt.

  5. Relations of water-quality constituent concentrations to surrogate measurements in the lower Platte River corridor, Nebraska, 2007 through 2011

    Science.gov (United States)

    Schaepe, Nathaniel J.; Soenksen, Philip J.; Rus, David L.

    2014-01-01

    The lower Platte River, Nebraska, provides drinking water, irrigation water, and in-stream flows for recreation, wildlife habitat, and vital habitats for several threatened and endangered species. The U.S. Geological Survey (USGS), in cooperation with the Lower Platte River Corridor Alliance (LPRCA) developed site-specific regression models for water-quality constituents at four sites (Shell Creek near Columbus, Nebraska [USGS site 06795500]; Elkhorn River at Waterloo, Nebr. [USGS site 06800500]; Salt Creek near Ashland, Nebr. [USGS site 06805000]; and Platte River at Louisville, Nebr. [USGS site 06805500]) in the lower Platte River corridor. The models were developed by relating continuously monitored water-quality properties (surrogate measurements) to discrete water-quality samples. These models enable existing web-based software to provide near-real-time estimates of stream-specific constituent concentrations to support natural resources management decisions. Since 2007, USGS, in cooperation with the LPRCA, has continuously monitored four water-quality properties seasonally within the lower Platte River corridor: specific conductance, water temperature, dissolved oxygen, and turbidity. During 2007 through 2011, the USGS and the Nebraska Department of Environmental Quality collected and analyzed discrete water-quality samples for nutrients, major ions, pesticides, suspended sediment, and bacteria. These datasets were used to develop the regression models. This report documents the collection of these various water-quality datasets and the development of the site-specific regression models. Regression models were developed for all four monitored sites. Constituent models for Shell Creek included nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, acetochlor, suspended sediment, and Escherichia coli (E. coli) bacteria. Regression models that were developed for the Elkhorn River included nitrate plus nitrite, total Kjeldahl nitrogen, total phosphorus

  6. Mortality Following Nursing Home-Acquired Lower Respiratory Infection: LRI Severity, Antibiotic Treatment, and Water Intake

    NARCIS (Netherlands)

    Szafara, K.L.; Kruse, R.; Mehr, D.; Ribbe, M.W.; van der Steen, J.T.

    2012-01-01

    Objective: In some nursing home populations, antibiotic treatment may not reduce mortality following lower respiratory infection (LRI). To better inform treatment decisions, we determined influences on mortality following LRI among antibiotic-treated and non-antibiotic-treated residents in 2

  7. [Severe burns of lower limb due to association of hot water and citrullus colocynthis].

    Science.gov (United States)

    Fejjal, N; Gharib, N E; El Mazouz, S; Abbassi, A; Belmahi, A

    2011-06-30

    The case is reported of a patient suffering from severe burns through having used Citrullus colocynthis as a medicinal plant together with hot water. This led to carbonization of the foot and to its amputation. A description of the plant and its toxicity is given.

  8. Cosurfactants lower surface tension of the diglyceride/water interface : A molecular dynamics study

    NARCIS (Netherlands)

    vanBuuren, AR; Tieleman, DP; deVlieg, J; Berendsen, HJC

    1996-01-01

    We performed molecular dynamics (MD) simulations of bulk 1,2-dilauroyl-sn-glycerol (DLG) systems in contact with a water layer. In the DLG oil phase cosurfactants were placed with increasing concentration: 1-monolauroyl-sn-glycerol (1MG), 2-monolauroylglycerol (2MG), and dodecanoic acid (FA, fatty

  9. Effects of flood control and other reservoir operations on the water quality of the lower Roanoke River, North Carolina

    Science.gov (United States)

    Garcia, Ana Maria

    2012-01-01

    The Roanoke River is an important natural resource for North Carolina, Virginia, and the Nation. Flood plains of the lower Roanoke River, which extend from Roanoke Rapids Dam to Batchelor Bay near Albemarle Sound, support a large and diverse population of nesting birds, waterfowl, freshwater and anadromous fish, and other wildlife, including threatened and endangered species. The flow regime of the lower Roanoke River is affected by a number of factors, including flood-management operations at the upstream John H. Kerr Dam and Reservoir. A three-dimensional, numerical water-quality model was developed to explore links between upstream flows and downstream water quality, specifically in-stream dissolved-oxygen dynamics. Calibration of the hydrodynamics and dissolved-oxygen concentrations emphasized the effect that flood-plain drainage has on water and oxygen levels, especially at locations more than 40 kilometers away from the Roanoke Rapids Dam. Model hydrodynamics were calibrated at three locations on the lower Roanoke River, yielding coefficients of determination between 0.5 and 0.9. Dissolved-oxygen concentrations were calibrated at the same sites, and coefficients of determination ranged between 0.6 and 0.8. The model has been used to quantify relations among river flow, flood-plain water level, and in-stream dissolved-oxygen concentrations in support of management of operations of the John H. Kerr Dam, which affects overall flows in the lower Roanoke River. Scenarios have been developed to mitigate the negative effects that timing, duration, and extent of flood-plain inundation may have on vegetation, wildlife, and fisheries in the lower Roanoke River corridor. Under specific scenarios, the model predicted that mean dissolved-oxygen concentrations could be increased by 15 percent by flow-release schedules that minimize the drainage of anoxic flood-plain waters. The model provides a tool for water-quality managers that can help identify options that improve

  10. VIDENTE: a graphical user interface and decision support system for stochastic modelling of water table fluctuations at a single location; includes documentation of the programs KALMAX, KALTFN, SSD and EMERALD and introductions to stochastic modellin

    NARCIS (Netherlands)

    Bierkens, M.F.P.; Bron, W.A.

    2000-01-01

    The VIDENTE program contains a decision support system (DSS) to choose between different models for stochastic modelling of water-table depths, and a graphical user interface to facilitate operating and running four implemented models: KALMAX, KALTFN,SSDS and EMERALD. In self-contained parts each of

  11. Sampling and analysis plan for treatment water and creek water for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-04-01

    This document provides the Environmental Restoration Program with information about the methodology, organizational structure, quality assurance and health and safety practices to be employed during the water sampling and analysis activities associated with the remediation of the Lower East Fork Poplar Creek Operable Unit during remediation of the National Oceanic and Atmospheric Administration and Bruner sites

  12. Sampling and analysis plan for treatment water and creek water for the Lower East Fork Poplar Creek Operable Unit, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This document provides the Environmental Restoration Program with information about the methodology, organizational structure, quality assurance and health and safety practices to be employed during the water sampling and analysis activities associated with the remediation of the Lower East Fork Poplar Creek Operable Unit during remediation of the National Oceanic and Atmospheric Administration and Bruner sites.

  13. Ground-water resources in the tri-state region adjacent to the Lower Delaware River

    Science.gov (United States)

    Barksdale, Henry C.; Greenman, David W.; Lang, Solomon Max; Hilton, George Stockbridge; Outlaw, Donald E.

    1958-01-01

    The purpose of this report is to appraise and evaluate the groundwater resources of a tri-state region adjacent to the lower Delaware River that is centered around Philadelphia, Pa., and Camden, N. J., and includes Wilmington, Del., and Trenton, N.J. Specifically, the region includes New Castle County, Del.; Burlington, Camden, Gloucester, Mercer, and Salem Counties in New Jersey; and Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties in Pennsylvania.

  14. Cold water immersion of the ankle decreases neuromuscular response of lower limb after inversion movement

    OpenAIRE

    Macedo, Christiane S. G.; Alonso, Carolina S.; Liporaci, Rogério F.; Vieira, Fernando; Guirro, Rinaldo R. J.

    2014-01-01

    BACKGROUND: Cryotherapy has been associated with a significant decrease in nerve conduction velocity and muscle contraction with possible effects on exercise and physical training. OBJECTIVES: To quantify the electromyographic response of the lateral gastrocnemius, tibialis anterior, fibularis longus, rectus femoris and gluteus medius to ankle inversion following cold water immersion. METHOD: The peak values of the root mean square (RMS) were obtained from 35 healthy and active univ...

  15. Monthly tables of measurements. October 2000

    International Nuclear Information System (INIS)

    2000-10-01

    This report of the O.P.R.I. (Office of Protection against Ionizing Radiations) exposes the principal results concerning the routine monitoring of environmental radioactivity in France: atmospheric dusts, rainwater, surface water, underground water, sewage water, drinking water, food chain (milk, vegetables, fishes), sea water around nuclear sites and other sites. The activities of various radioisotopes are presented in tables. (N.C.)

  16. Water

    International Nuclear Information System (INIS)

    Chovanec, A.; Grath, J.; Kralik, M.; Vogel, W.

    2002-01-01

    An up-date overview of the situation of the Austrian waters is given by analyzing the status of the water quality (groundwater, surface waters) and water protection measures. Maps containing information of nitrate and atrazine in groundwaters (analyses at monitoring stations), nitrate contents and biological water quality of running waters are included. Finally, pollutants (nitrate, orthophosphate, ammonium, nitrite, atrazine etc.) trends in annual mean values and median values for the whole country for the years 1992-1999 are presented in tables. Figs. 5. (nevyjel)

  17. Evaluating Capability of Devils Lake Emergency Outlets in Lowering Lake Water Levels While Controlling flooding Damage to Downstream

    Science.gov (United States)

    Shabani, A.; Zhang, X.

    2017-12-01

    Devils Lake is an endorheic lake locate in the Red River of the North Basin with a natural outlet at a level of 444.7 meters above the sea level flowing into the Sheyenne River. Historical accumulation of salts has dramatically increased the concentration of salts in the lake, particularly of the sulfates, that are much greater than the surrounding water bodies. Since 1993, the lake water level has risen by nearly 10 meters and caused extensive flooding in the surrounding area, and greatly increased the chance of natural spillage to the Sheyenne River. To mitigate Devils Lake flooding and to prevent its natural spillage, two outlets were constructed at the west and east sides of the lake to drain the water to the Sheyenne River in a controlled fashion. However, pumping water from Devils Lake has degraded water quality of the Sheyenne River. In an earlier study, we coupled Soil and Water Assessment Tools (SWAT) and CE-QUAL-W2 models to investigate the changes of sulfate distribution as the lake water level rises. We found that, while operating the two outlets has lowered Devils Lake water level by 0.7 meter, it has also significantly impaired the Sheyenne River water quality, increasing the Sheyenne River average sulfate concentration from 105 to 585 mg l-1 from 2012 to 2014 In this study, we investigate the impact of the outlets on the Sheyenne River floodplain by coupling SWAT and HEC-RAS model. The SWAT model performed well in simulating daily streamflow in the Sheyenne River with R2>0.56 and ENS > 0.52. The simulated water depths and floodplain by HEC-RAS model for the Sheyenne River agreed well with observations. Operating the outlets from April to October can draw down the Devil Lake water level by 0.45 m, but the drained water would almost double the extension of the Sheyenne River floodplain and elevate the sulfate concentration in the Sheyenne River above the 450 mg l-1 North Dakota sulfate concentration standard for stream class I. Operating the outlets is

  18. A study on uranium metallogenetic prospects of ground water oxidation zone type in the lower cretaceous, north Shanganning basin

    International Nuclear Information System (INIS)

    Wang Jinping

    2000-01-01

    Lower Cretaceous is developed well in the north part of Shanganning basin. The area was widely uplifting vertically after their deposited. Based on the features of lithology, lithophase and Neotectonic forms, two main periods of oxidation-erosion of K2-E1 and N1-present can be distinguished. During these two periods, large scale horizontal oxidation were occurred. It is significant that the ground water oxidation related to the uranium mineralization and has been proved by the field investigation and the data of γ-logging in drill hole for oil. Meanwhile, according to the hydrodynamic features of present Shanganning plateau type artesian basin, it seems that uranium mineralization main related to the ground water oxidation the upper parts of the Lower Cretaceous

  19. Coupled eco-hydrology and biogeochemistry algorithms enable the simulation of water table depth effects on boreal peatland net CO2 exchange

    Science.gov (United States)

    Mezbahuddin, Mohammad; Grant, Robert F.; Flanagan, Lawrence B.

    2017-12-01

    Water table depth (WTD) effects on net ecosystem CO2 exchange of boreal peatlands are largely mediated by hydrological effects on peat biogeochemistry and the ecophysiology of peatland vegetation. The lack of representation of these effects in carbon models currently limits our predictive capacity for changes in boreal peatland carbon deposits under potential future drier and warmer climates. We examined whether a process-level coupling of a prognostic WTD with (1) oxygen transport, which controls energy yields from microbial and root oxidation-reduction reactions, and (2) vascular and nonvascular plant water relations could explain mechanisms that control variations in net CO2 exchange of a boreal fen under contrasting WTD conditions, i.e., shallow vs. deep WTD. Such coupling of eco-hydrology and biogeochemistry algorithms in a process-based ecosystem model, ecosys, was tested against net ecosystem CO2 exchange measurements in a western Canadian boreal fen peatland over a period of drier-weather-driven gradual WTD drawdown. A May-October WTD drawdown of ˜ 0.25 m from 2004 to 2009 hastened oxygen transport to microbial and root surfaces, enabling greater microbial and root energy yields and peat and litter decomposition, which raised modeled ecosystem respiration (Re) by 0.26 µmol CO2 m-2 s-1 per 0.1 m of WTD drawdown. It also augmented nutrient mineralization, and hence root nutrient availability and uptake, which resulted in improved leaf nutrient (nitrogen) status that facilitated carboxylation and raised modeled vascular gross primary productivity (GPP) and plant growth. The increase in modeled vascular GPP exceeded declines in modeled nonvascular (moss) GPP due to greater shading from increased vascular plant growth and moss drying from near-surface peat desiccation, thereby causing a net increase in modeled growing season GPP by 0.39 µmol CO2 m-2 s-1 per 0.1 m of WTD drawdown. Similar increases in GPP and Re caused no significant WTD effects on modeled

  20. Coupled eco-hydrology and biogeochemistry algorithms enable the simulation of water table depth effects on boreal peatland net CO2 exchange

    Directory of Open Access Journals (Sweden)

    M. Mezbahuddin

    2017-12-01

    Full Text Available Water table depth (WTD effects on net ecosystem CO2 exchange of boreal peatlands are largely mediated by hydrological effects on peat biogeochemistry and the ecophysiology of peatland vegetation. The lack of representation of these effects in carbon models currently limits our predictive capacity for changes in boreal peatland carbon deposits under potential future drier and warmer climates. We examined whether a process-level coupling of a prognostic WTD with (1 oxygen transport, which controls energy yields from microbial and root oxidation–reduction reactions, and (2 vascular and nonvascular plant water relations could explain mechanisms that control variations in net CO2 exchange of a boreal fen under contrasting WTD conditions, i.e., shallow vs. deep WTD. Such coupling of eco-hydrology and biogeochemistry algorithms in a process-based ecosystem model, ecosys, was tested against net ecosystem CO2 exchange measurements in a western Canadian boreal fen peatland over a period of drier-weather-driven gradual WTD drawdown. A May–October WTD drawdown of  ∼  0.25 m from 2004 to 2009 hastened oxygen transport to microbial and root surfaces, enabling greater microbial and root energy yields and peat and litter decomposition, which raised modeled ecosystem respiration (Re by 0.26 µmol CO2 m−2 s−1 per 0.1 m of WTD drawdown. It also augmented nutrient mineralization, and hence root nutrient availability and uptake, which resulted in improved leaf nutrient (nitrogen status that facilitated carboxylation and raised modeled vascular gross primary productivity (GPP and plant growth. The increase in modeled vascular GPP exceeded declines in modeled nonvascular (moss GPP due to greater shading from increased vascular plant growth and moss drying from near-surface peat desiccation, thereby causing a net increase in modeled growing season GPP by 0.39 µmol CO2 m−2 s−1 per 0.1 m of WTD drawdown. Similar increases in

  1. A phenomenological analysis of melt progression in the lower head of a pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, J.M., E-mail: jean-marie.seiler@cea.fr [CEA, DEN, DTN, F-38054 Grenoble (France); Tourniaire, B. [EDF/Septen, Lyon (France)

    2014-03-15

    Highlights: • We propose a phenomenological description of melt progression into the lower head. • We examine changes in heat loads on the vessel. • Heat loads are more severe than emphasized by the bounding situation assumption. • Both primary circuit and ex-vessel reflooding are necessary for in-vessel retention. • Vessel failure conditions are examined. - Abstract: The analysis of in-vessel corium cooling (IVC) and retention (IVR) involves the description of very complex and transient physical phenomena. To get round this difficulty, “bounding” situations are often emphasized for the demonstration of corium coolability, by vessel flooding and/or by reactor pit flooding. This approach however comes up against its own limitations. More realistic melt progression scenarios are required to provide plausible corium configurations and vessel failure conditions. Work to develop more realistic melt progression scenarios has been done at CEA, in collaboration with EDF. Development has concentrated on the French 1300 MWe PWR, considering both dry scenarios and the possibility of flooding of the RPC (reactor primary circuit) and/or the reactor pit. The models used for this approach have been derived from the analysis of the TMI2 accident and take benefit from the lessons derived from several programs related to pool thermal hydraulics (BALI, COPO, ACOPO, etc.), material interactions (RASPLAV, MASCA), critical heat flux (CHF) on the external surface of the vessel (KAIST, SULTAN, ULPU), etc. Important conclusions of this work are as follows: (a)After the start of corium melting and onset of melt formation in the core at low pressure (∼1 to 5 bars), it seems questionable that RPV (reactor pressure vessel) reflooding alone would be sufficient to achieve corium retention in the vessel; (b)If the vessel is not cooled externally, it may fail due to local heat-up before the whole core fuel inventory is relocated in the lower head; (c)Even if the vessel is

  2. Process for selectivity lowering the water permeability of a crude oil deposit

    Energy Technology Data Exchange (ETDEWEB)

    Katser, M F

    1966-10-20

    In this process for selectively reducing the water permeability of oil-bearing formations, especially during waterflooding, an aqueous solution is injected into the producing well. This solution contains a hydrolyzed acryl amide polymer, polyacrylamide or a copolymer, the greater part of which is acrylamide and the smaller part a polymerizable monomer, e.g., vinyl alcohol, vinyl chloride, acrylonitrile, methacrylonitrile or vinyl acryl ether. About 0.5-67.0% of the carboxy amide groups of the acrylamide polymer are hydrolyzed to carboxilic groups. The concentration of the hydrolyzed acrylamide polymer in the solution is about 0.01-1.0%. (3 claims)

  3. Retrieval of water vapor vertical distributions in the upper troposphere and the lower stratosphere from SCIAMACHY limb measurements

    Directory of Open Access Journals (Sweden)

    A. Rozanov

    2011-05-01

    Full Text Available This study describes the retrieval of water vapor vertical distributions in the upper troposphere and lower stratosphere (UTLS altitude range from space-borne observations of the scattered solar light made in limb viewing geometry. First results using measurements from SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY aboard ENVISAT (Environmental Satellite are presented here. In previous publications, the retrieval of water vapor vertical distributions has been achieved exploiting either the emitted radiance leaving the atmosphere or the transmitted solar radiation. In this study, the scattered solar radiation is used as a new source of information on the water vapor content in the UTLS region. A recently developed retrieval algorithm utilizes the differential absorption structure of the water vapor in 1353–1410 nm spectral range and yields the water vapor content in the 11–25 km altitude range. In this study, the retrieval algorithm is successfully applied to SCIAMACHY limb measurements and the resulting water vapor profiles are compared to in situ balloon-borne observations. The results from both satellite and balloon-borne instruments are found to agree typically within 10 %.

  4. Water vapor increase in the northern hemispheric lower stratosphere by the Asian monsoon anticyclone observed during TACTS campaign in 2012

    Science.gov (United States)

    Rolf, Christian; Vogel, Bärbel; Hoor, Peter; Günther, Gebhard; Krämer, Martina; Müller, Rolf; Müller, Stephan; Riese, Martin

    2017-04-01

    Water vapor plays a key role in determining the radiative balance in the upper troposphere and lower stratosphere (UTLS) and thus the climate of the Earth (Forster and Shine, 2002; Riese et al., 2012). Therefore a detailed knowledge about transport pathways and exchange processes between troposphere and stratosphere is required to understand the variability of water vapor in this region. The Asian monsoon anticyclone caused by deep convection over and India and east Asia is able to transport air masses from the troposphere into the nothern extra-tropical stratosphere (Müller et al. 2016, Vogel et al. 2016). These air masses contain pollution but also higher amounts of water vapor. An increase in water vapor of about 0.5 ppmv in the extra-tropical stratosphere above a potential temperature of 380 K was detected between August and September 2012 by in-situ instrumentation above the European northern hemisphere during the HALO aircraft mission TACTS. Here, we investigated the origin of this water vapor increase with the help of the 3D Lagrangian chemistry transport model CLaMS (McKenna et al., 2002). We can assign an origin of the moist air masses in the Asian region (North and South India and East China) with the help of model origin tracers. Additionally, back trajectories of these air masses with enriched water vapor are used to differentiate between transport from the Asia monsoon anticyclone and the upwelling of moister air in the tropics particularly from the Pacific and Southeast Asia.

  5. Sodium removal from CSRDM lower part by water vapour - CO2 process

    International Nuclear Information System (INIS)

    Sundar Raj, S.I.; Sreedhar, B.K.; Gurumoorthy, K.; Rajan, K.K.; Kalyanasundaram, P.; Rajan, M.; Vaidyanathan, G.

    2006-01-01

    Sodium is the primary and secondary coolant in fast reactors. Primary and secondary circuits components like Control and Safety Rod Drive Mechanism (CSRDM), pumps, heat exchangers etc. handle liquid sodium. Sodium has good affinity to oxygen and reacts vigorously with water. Hence sodium cleaning is the first and important activity in the maintenance of the components. In reactor components this cleaning process also helps in removing a major part of radioactive contaminants after which they are subjected to chemical decontamination. There are several methods available for removing sodium from components. Out of these, the water vapour-CO 2 process is selected for large components such as pumps, heat exchangers etc. while steam cleaning is used for the core sub assemblies. The cleaning processes are to be closely monitored to ensure safety because the release of hydrogen is to be kept below 4 % during the process. This paper discusses the in house facility and the experience in the successful use of the process in the cleaning of CSRDM. (author)

  6. Epipelic Diatoms as Indicators of Water Quality in the Lower Part of River Melet (Ordu, Türkiye

    Directory of Open Access Journals (Sweden)

    Beyhan Taş

    2015-07-01

    Full Text Available Phytobenthos includes bioindicator species and is widely used in water ecology studies. Diatoms constitute one of the most important groups of phytobenthos in streams. In particular, these organisms are good indicators in investigations related with determining of water quality in medium and long time. In this study, the epipelic diatom flora of the lower part of River Melet were investigated, the most important source of drinking water in Ordu city. The examination was performed periodically in March-November 2012 and total of 56 taxa were identified. Cymbellales (14 taxa and Naviculales (16 taxa ordo constituted 54% of diatom diversity. These were followed by Fragilariales (16%, 9 taxa Bacillariales (14%, 8 taxa Surirellales (9%, 5 taxa Achnanthales (3%, 2 taxa Eunotiales (2%, 1 taxa and Melosirales (2%, 1 taxa, respectively. Diatome vulgaris, Melosira varians, Navicula gregaria, N. tripunctata and Nitzschia sigmoidea species were recorded as widespread and intense in the epipelic communities. These species are usually tolerant to organic pollution and are found in β-α- mesosaprobic conditions. According to the obtained results, the lower part of the Melet River has character from pollution towards moderate pollution. In other words, it has II-III. class water quality.

  7. Satial and seasonal variations o heavy metals in water and sediment samles collected rom the Lower Danube River

    Directory of Open Access Journals (Sweden)

    IONESCU Petra

    2016-12-01

    Full Text Available Surface water pollution with heavy metals represents one of the most relevant environmental issues, with severe outcomes on every other environmental compartment, affecting therefore the human health because of their toxicity, persistence and bioaccumulation tendency. The Danube, one of the most important rivers of Europe considering its course, crossing the continent from west to east, represents the main collector of all pollutants emitted by the ten countries it passes through, prior to discharging into the Black Sea. Given all this, and because of the possible unwanted effects that may occur as a result of recent constructions taking place in the area to improve the navigation conditions, the aim of this study is to evaluate the variation of the global concentration of heavy metals in both water and sediments by calculating the Metal Pollution Index (MPI on the sector between Calarasi - Braila (km 370 - km 170. Water and sediment samples from Lower Danube were collected between January 2012 and December 2013, from ten different sites. The following heavy metals have been determined: chromium (Cr, copper (Cu, zinc (Zn, lead (Pb and nickel (Ni. Metal Pollution Index values were used for a seasonal and spatial comparison of the total metal content from the established sites. For a more detailed interpretation of results, Cluster Analysis was performed. Frequent monitoring of the heavy metal content of Lower Danube has a significant impact on water quality, keeping a low pollution risk and having a long term positive impact on environmental protection of the Black Sea Basin.

  8. Chemical concentrations in water and suspended sediment, Green River to Lower Duwamish Waterway near Seattle, Washington, 2016–17

    Science.gov (United States)

    Conn, Kathleen E.; Black, Robert W.; Peterson, Norman T.; Senter, Craig A.; Chapman, Elena A.

    2018-01-05

    From August 2016 to March 2017, the U.S. Geological Survey (USGS) collected representative samples of filtered and unfiltered water and suspended sediment (including the colloidal fraction) at USGS streamgage 12113390 (Duwamish River at Golf Course, at Tukwila, Washington) during 13 periods of differing flow conditions. Samples were analyzed by Washington-State-accredited laboratories for a large suite of compounds, including metals, dioxins/furans, semivolatile compounds including polycyclic aromatic hydrocarbons, butyltins, the 209 polychlorinated biphenyl (PCB) congeners, and total and dissolved organic carbon. Concurrent with the chemistry sampling, water-quality field parameters were measured, and representative water samples were collected and analyzed for river suspended-sediment concentration and particle-size distribution. The results provide new data that can be used to estimate sediment and chemical loads transported by the Green River to the Lower Duwamish Waterway.

  9. investigating water absorption and thickness swelling tendencies

    African Journals Online (AJOL)

    HOD

    In addition, G30E (30% reinforced glass fibre in the epoxy composite) was more resilient to moisture ... determine its suitability as per its water absorption and thickness ... lower thermal conductivity and low density as outlined in the Tables.

  10. Stability analysis of roadway embankments supported by stone columns with the presence of water table under short-term and long-term conditions

    Directory of Open Access Journals (Sweden)

    Kadhim Shaymaa Tareq

    2018-01-01

    Full Text Available Use of stone column technique to improve soft foundation soils under roadway embankments has proven to increase the bearing capacity and reduce the potential settlement. The potential contribution of stone columns to the stability of roadway embankments against general (i.e. deep-seated failure needs to be thoroughly investigated. Therefore, a two-dimensional finite difference model implemented by FLAC/SLOPE 7.0 software, was employed in this study to assess the stability of a roadway embankment fill built on a soft soil deposit improved by stone column technique. The stability factor of safety was obtained numerically under both short-term and long-term conditions with the presence of water table. Two methods were adopted to convert the three-dimensional model into plane strain condition: column wall and equivalent improved ground methods. The effect of various parameters was studied to evaluate their influence on the factor of safety against embankment instability. For instance, the column diameter, columns’ spacing, soft soil properties for short-term and long-term conditions, and the height and friction angle of the embankment fill. The results of this study are developed in several design charts.

  11. The economic value of detailed soil survey in a drinking water collection area in the Netherlands

    NARCIS (Netherlands)

    Knotters, M.; Vroon, H.R.J.

    2015-01-01

    In large parts of the Netherlands crop growth depends on the water table. If groundwater is withdrawn the water table is lowered and agricultural crop production may be reduced. Farmers in drinking water collection areas are legally compensated for these crop yield reductions. Soil maps are used to

  12. Do Reductions in Dry Season Transpiration Allow Shallow Soil Water Uptake to Persist in a Tropical Lower Montane Cloud Forest?

    Science.gov (United States)

    Munoz Villers, L. E.; Holwerda, F.; Alvarado-Barrientos, M. S.; Goldsmith, G. R.; Geissert Kientz, D. R.; González Martínez, T. M.; Dawson, T. E.

    2016-12-01

    Tropical montane cloud forests (TMCF) are ecosystems particularly sensitive to climate change; however, the effects of warmer and drier conditions on TMCF water cycling remain poorly understood. To investigate the plant functional response to reduced water availability, we conducted a study during the mid to late dry season (2014) in the lower limit (1,325 m asl) of the TMCF belt (1200-2500 m asl) in central Veracruz, Mexico. The temporal variation of transpiration rates of dominant upper canopy and mid-story tree species, depth of water uptake, as well as tree water sources were examined using micrometeorological, sapflow and soil moisture measurements, in combination with data on stable isotope (δ18O and δ2H) composition of rain, tree xylem, soil (bulk and low suction-lysimeter) and stream water. The sapflow data suggest that crown conductances decreased as temperature and vapor pressure deficit increased, and soil moisture decreased from the mid to late dry season. Across all samplings (January 21, April 12 and 26), upper canopy species (Quercus spp.) showed more depleted (negative) isotope values compared to mid-story trees (Carpinus tropicalis). Overall, we found that the evaporated soil water pool was the main source for the trees. Furthermore, our MixSIAR Bayesian mixing model results showed that the depth of tree water uptake changed over the course of the dry season. Unexpectedly, a shift in water uptake from deeper (60-120 cm depth) to shallower soil water (0-30 cm) sources was observed, coinciding with the decreases in transpiration rates towards the end of the dry season. A larger reduction in deep soil water contributions was observed for upper canopy trees (from 70±14 to 22±15%) than for mid-story species (from 10±13 to 7±10%). The use of shallow soil water by trees during the dry season seems consistent with the greater root biomass and higher macronutrient concentrations found in the first 10 cm of the soil profiles. These findings are an

  13. Distribution of acidic and neutral drugs in surface waters near sewage treatment plants in the lower Great Lakes, Canada.

    Science.gov (United States)

    Metcalfe, Chris D; Miao, Xiu-Sheng; Koenig, Brenda G; Struger, John

    2003-12-01

    Prescription and nonprescription drugs have been detected in rivers and streams in Europe and the United States. Sewage treatment plants (STPs) are an important source of these contaminants, but few data exist on the spatial distribution of drugs in surface waters near STPs. Samples of surface water were collected in the summer and fall of 2000 at open-water sites in the lower Great Lakes (Lake Ontario and Lake Erie), at sites near the two STPs for the city of Windsor (ON, Canada), and at sites in Hamilton Harbour (ON, Canada), an embayment of western Lake Ontario that receives discharges from several STPs. In a follow-up study in the summer of 2002, samples of surface water and final effluent from adjacent STPs were collected from sites in Hamilton Harbour and Windsor. In addition, surface water and STP effluent samples were collected in Peterborough (ON, Canada). All samples of surface water and STP effluents were analyzed for selected acidic and neutral drugs. In the survey of Hamilton Harbour and Windsor conducted in 2000, acidic drugs and the antiepileptic drug carbamazepine were detected at ng/L concentrations at sites that were up to 500 m away from the STP, but the hydrological conditions of the receiving waters strongly influenced the spatial distribution of these compounds. Drugs were not detected at open-water locations in western Lake Erie or in the Niagara River near the municipality of Niagara-on-the-Lake (ON, Canada). However, clofibric acid, ketoprofen, fenoprofen, and carbamazepine were detected in samples collected in the summer of 2000 at sites in Lake Ontario and at a site in the Niagara River (Fort Erie, ON, Canada) that were relatively remote from STP discharges. Follow-up studies in the summer of 2002 indicated that concentrations of acidic and neutral drugs in surface waters near the point of sewage discharge into the Little River (ON, Canada) STP were approximately equal to the concentrations in the final effluent from the STP. Caffeine and

  14. Scoping Assessment for Developing a Water Quality Monitoring Plan to Support Application of the CE-QUAL-W2 Hydrodynamic and Water Quality Model to the Lower Missouri River downstream of Gavins Point Dam

    Science.gov (United States)

    2010-04-01

    setting up input geometry for the Missouri River : 1) channel geometry will be obtained from previous HEC - RAS modeling of the lower Missouri River , and 2...stage-discharge rating curves developed for USGS and USACE gaging stations on the Missouri River . HEC - RAS (Hydrologic Engineering Center- River ...adjusted to better match the “project” table. For the lower Missouri River , initial cell widths will be derived from past HEC - RAS modeling

  15. 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

  16. Surface water quality and isotopic study at a section of the Lower Volta River (Akuse to Sogakope area), Ghana

    International Nuclear Information System (INIS)

    Gampson, E. K.

    2012-01-01

    The water quality examination at a section of the Lower Volta River (Akuse to the Sogakope area), Ghana, was conducted by determining the physicochemical parameters at 38 sampling sites in September (2011) during the wet season and February (2012) during the dry season. Isotope analysis was also conducted during the same period. The ranges of physicochemical parameters analysed in the surface water were 6.45 to 7.26 for pH, -053 to -010 mV for Eh, 23.6 to 27 degrees celsius for temperature, 61.7 to 83.6 μS/cm for EC, 0% 0 for salinity, 29.7-39.4 mg/L for TDS, 0.63 to 2.28 mg/L for DO, 0 to 4 NTU for turbidity, 0 to 8mg/L for TSS, 36 to 108mg/L for total hardness, 0.8 to 5mg/L for BOD 5 , 23.16 to 46.33mg/L for HCO 3 - , 2.92 to 23.33mg/L for Mg 2+ , 7.8 to 11.0mg/L for Na + , 4.0 to 5.9mg/L for K + , 1.99 to 13.99mg/L for CI - , 3.2 to 14.4MG/L for Ca 2+ , 1.0 to 24.889mg/L for NO 3 - , 6.556 to 28.111mg/L for SO 4 2- and 1.333 to 11.667mg/L for PO 4 3- . While the results for dissolved metals (μg/L) were 32 to 348 for Fe, 12 to 278 for Mn, 16 to 84 for Cu, 4 to 38 for Pb, 20 to 162 for Ni, 12 to 32 for Cd and 12μg/L to 98 for Cd, Hg, Se, V and Zn were below detection limit. The river water will support agricultural activities. Except Cu which was low, about 37%, 89%, 29%, 33%, 8% and 29% of the sampled sites had Pb, Ni, Cd, Cr, Fe and Mn values respectively above the WHO (2004) standard for drinking water. Therefore, water quality monitoring and control of release of untreated anthropogenic wastes into the river is strongly needed. Stable isotope data of water (δ 2 H and δ 18 O) obtained showed stream waters are depleted and possibly recharge by rain and waters from the Akwapim Mountains than the isotopically heavy evaporated waters found within the Lower Volta River. (au)

  17. Proposed upgrade of the lower tier water moderators for the LANSE 1L MARK-III upgrade

    International Nuclear Information System (INIS)

    Muhrer, G.; Pitcher, E.J.; Russell, G.J.

    2005-01-01

    We will show in this article the proposed upgrade for the lower tier water moderators for the LANSCE 1L Mark-III design. This proposal will include the introduction of pre-moderators for the high intensity moderators and a change of the decoupler from Cadmium to Gadolinium on all lower tier water moderators. We will present the influence of these changes on the integrated thermal flux and the time distribution of these moderators. As part of the upgrade of the Manual Lujan Jr. Neutron Scattering Center target (1L target) the goal was to increase the integrated thermal flux of the lower high intensity and the high resolution moderator by 20%. We will show in this paper that this goal can be achieved by introducing a pre-moderator concept on the high resolution moderators and by changing the decoupling scheme on all three moderators. Furthermore we will show that this goal can be achieved without jeopardizing the time of flight resolution of these moderators. For the all these calculations we used the radiation transport code MCNPX, which is most commonly used for this type of calculations.

  18. Geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples, and its possible relationship with the prevalence of enamel fluorosis in children in four municipalities of the department of Huila (Colombia).

    Science.gov (United States)

    Martignon, Stefania; Opazo-Gutiérrez, Mario Omar; Velásquez-Riaño, Möritz; Orjuela-Osorio, Iván Rodrigo; Avila, Viviana; Martinez-Mier, Esperanza Angeles; González-Carrera, María Clara; Ruiz-Carrizosa, Jaime Alberto; Silva-Hermida, Blanca Cecilia

    2017-06-01

    Fluoride is an element that affects teeth and bone formation in animals and humans. Though the use of systemic fluoride is an evidence-based caries preventive measure, excessive ingestion can impair tooth development, mainly the mineralization of tooth enamel, leading to a condition known as enamel fluorosis. In this study, we investigated the geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples in four endemic enamel fluorosis sentinel municipalities of the department of Huila, Colombia (Pitalito, Altamira, El Agrado and Rivera), and its possible relationship with the prevalence of enamel fluorosis in children. The concentration of fluoride in drinking water, table salt, active sediment, rock, and soil was evaluated by means of an ion selective electrode and the geochemical analyses were performed using X-ray fluorescence. Geochemical analysis revealed fluoride concentrations under 15 mg/kg in active sediment, rock and soil samples, not indicative of a significant delivery to the watersheds studied. The concentration of fluoride in table salt was found to be under the inferior limit (less than 180 μg/g) established by the Colombian regulations. Likewise, exposure doses for fluoride water intake did not exceed the recommended total dose for all ages from 6 months. Although the evidence does not point out at rocks, soils, fluoride-bearing minerals, fluoridated salt and water, the hypothesis of these elements as responsible of the current prevalence of enamel fluorosis cannot be discarded since, aqueducts might have undergone significant changes overtime.

  19. NNDSS - Table III. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table III. Tuberculosis - 2018.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  20. Pension Insurance Data Tables

    Data.gov (United States)

    Pension Benefit Guaranty Corporation — Find out about retirement trends in PBGC's data tables. The tables include statistics on the people and pensions that PBGC protects, including how many Americans are...

  1. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2016.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  2. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2014.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  3. NNDSS - Table II. Vibriosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Vibriosis - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year), and selected...

  4. NNDSS - Table III. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table III. Tuberculosis - 2017.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  5. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2015.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  6. NNDSS - Table II. Vibriosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Vibriosis - 2018. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year), and selected...

  7. Tabled Execution in Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Willcock, J J; Lumsdaine, A; Quinlan, D J

    2008-08-19

    Tabled execution is a generalization of memorization developed by the logic programming community. It not only saves results from tabled predicates, but also stores the set of currently active calls to them; tabled execution can thus provide meaningful semantics for programs that seemingly contain infinite recursions with the same arguments. In logic programming, tabled execution is used for many purposes, both for improving the efficiency of programs, and making tasks simpler and more direct to express than with normal logic programs. However, tabled execution is only infrequently applied in mainstream functional languages such as Scheme. We demonstrate an elegant implementation of tabled execution in Scheme, using a mix of continuation-passing style and mutable data. We also show the use of tabled execution in Scheme for a problem in formal language and automata theory, demonstrating that tabled execution can be a valuable tool for Scheme users.

  8. Filling the gap: using non-invasive geophysical methods to monitor the processes leading to enhanced carbon turnover induced by periodic water table fluctuations

    Science.gov (United States)

    Mellage, A.; Pronk, G.; Atekwana, E. A.; Furman, A.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Subsurface transition environments such as the capillary fringe are characterized by steep gradients in redox conditions. Spatial and temporal variations in electron acceptor and donor availability - driven by hydrological changes - may enhance carbon turnover, in some cases resulting in pulses of CO2-respiration. Filling the mechanistic knowledge gap between the hydrological driver and its biogeochemical effects hinges on our ability to monitor microbial activity and key geochemical markers at a high spatial and temporal resolution. However, direct access to subsurface biogeochemical processes is logistically difficult, invasive and usually expensive. In-line, non-invasive geophysical techniques - Spectral Induced Polarization (SIP) and Electrodic Potential (EP), specifically - offer a comparatively inexpensive alternative and can provide data with high spatial and temporal resolution. The challenge lies in linking electrical responses to specific changes in biogeochemical processes. We conducted SIP and EP measurements on a soil column experiment where an artificial soil mixture was subjected to monthly drainage and imbibition cycles. SIP responses showed a clear dependence on redox zonation and microbial abundance. Temporally variable responses exhibited no direct moisture dependence suggesting that the measured responses recorded changes in microbial activity and coincided with the depth interval over which enhanced carbon turnover was observed. EP measurements detected the onset of sulfate mineralization and mapped its depth zonation. SIP and EP signals thus detected enhanced microbial activity within the water table fluctuation zone as well as the timing of the development of specific reactive processes. These findings can be used to relate measured electrical signals to specific reaction pathways and help inform reactive transport models, increasing their predictive capabilities.

  9. Water-quality and biological conditions in selected tributaries of the Lower Boise River, southwestern Idaho, water years 2009-12

    Science.gov (United States)

    Etheridge, Alexandra B.; MacCoy, Dorene E.; Weakland, Rhonda J.

    2014-01-01

    Water-quality conditions were studied in selected tributaries of the lower Boise River during water years 2009–12, including Fivemile and Tenmile Creeks in 2009, Indian Creek in 2010, and Mason Creek in 2011 and 2012. Biological samples, including periphyton biomass and chlorophyll-a, benthic macroinvertebrates, and fish were collected in Mason Creek in October 2011. Synoptic water-quality sampling events were timed to coincide with the beginning and middle of the irrigation season as well as the non-irrigation season, and showed that land uses and irrigation practices affect water quality in the selected tributaries. Large increases in nutrient and sediment concentrations and loads occurred over relatively short stream reaches and affected nutrient and sediment concentrations downstream of those reaches. Escherichia coli (E. coli) values increased in study reaches adjacent to pastured lands or wastewater treatment plants, but increased E. coli values at upstream locations did not necessarily affect E. coli values at downstream locations. A spatial loading analysis identified source areas for nutrients, sediment, and E. coli, and might be useful in selecting locations for water-quality improvement projects. Effluent from wastewater treatment plants increased nutrient loads in specific reaches in Fivemile and Indian Creeks. Increased suspended-sediment loads were associated with increased discharge from irrigation returns in each of the studied tributaries. Samples collected during or shortly after storms showed that surface runoff, particularly during the winter, may be an important source of nutrients in tributary watersheds with substantial agricultural land use. Concentrations of total phosphorus, suspended sediment, and E. coli exceeded regulatory water-quality targets or trigger levels at one or more monitoring sites in each tributary studied, and exceedences occurred during irrigation season more often than during non-irrigation season. As with water

  10. AcuTable

    DEFF Research Database (Denmark)

    Dibbern, Simon; Rasmussen, Kasper Vestergaard; Ortiz-Arroyo, Daniel

    2017-01-01

    In this paper we describe AcuTable, a new tangible user interface. AcuTable is a shapeable surface that employs capacitive touch sensors. The goal of AcuTable was to enable the exploration of the capabilities of such haptic interface and its applications. We describe its design and implementation...

  11. Table Tennis Club

    CERN Multimedia

    Table Tennis Club

    2013-01-01

    Apparently table tennis plays an important role in physics, not so much because physicists are interested in the theory of table tennis ball scattering, but probably because it provides useful breaks from their deep intellectual occupation. It seems that many of the greatest physicists took table tennis very seriously. For instance, Heisenberg could not even bear to lose a game of table tennis, Otto Frisch played a lot of table tennis, and had a table set up in his library, and Niels Bohr apparently beat everybody at table tennis. Therefore, as the CERN Table Tennis Club advertises on a poster for the next CERN Table Tennis Tournament: “if you want to be a great physicist, perhaps you should play table tennis”. Outdoor table at restaurant n° 1 For this reason, and also as part of the campaign launched by the CERN medical service “Move! & Eat better”, to encourage everyone at CERN to take regular exercise, the CERN Table Tennis Club, with the supp...

  12. Periodic Table of Students.

    Science.gov (United States)

    Johnson, Mike

    1998-01-01

    Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

  13. Substantive hemodynamic and thermal strain upon completing lower-limb hot-water immersion; comparisons with treadmill running.

    Science.gov (United States)

    Thomas, Kate N; van Rij, André M; Lucas, Samuel J E; Gray, Andrew R; Cotter, James D

    2016-01-01

    Exercise induces arterial flow patterns that promote functional and structural adaptations, improving functional capacity and reducing cardiovascular risk. While heat is produced by exercise, local and whole-body passive heating have recently been shown to generate favorable flow profiles and associated vascular adaptations in the upper limb. Flow responses to acute heating in the lower limbs have not yet been assessed, or directly compared to exercise, and other cardiovascular effects of lower-limb heating have not been fully characterized. Lower-limb heating by hot-water immersion (30 min at 42°C, to the waist) was compared to matched-duration treadmill running (65-75% age-predicted heart rate maximum) in 10 healthy, young adult volunteers. Superficial femoral artery shear rate assessed immediately upon completion was increased to a greater extent following immersion (mean ± SD: immersion +252 ± 137% vs. exercise +155 ± 69%, interaction: p = 0.032), while superficial femoral artery flow-mediated dilation was unchanged in either intervention. Immersion increased heart rate to a lower peak than during exercise (immersion +38 ± 3 beats·min -1 vs. exercise +87 ± 3 beats·min -1 , interaction: p immersion reduced mean arterial pressure after exposure (-8 ± 3 mmHg, p = 0.012). Core temperature increased twice as much during immersion as exercise (+1.3 ± 0.4°C vs. +0.6 ± 0.4°C, p immersion has potential to induce favorable shear stress patterns and cardiovascular responses within vessels prone to atherosclerosis. Whether repetition of lower-limb heating has long-term beneficial effects in such vasculature remains unexplored.

  14. Determination of total arsenic and arsenic species in drinking water, surface water, wastewater, and snow from Wielkopolska, Kujawy-Pomerania, and Lower Silesia provinces, Poland.

    Science.gov (United States)

    Komorowicz, Izabela; Barałkiewicz, Danuta

    2016-09-01

    Arsenic is a ubiquitous element which may be found in surface water, groundwater, and drinking water. In higher concentrations, this element is considered genotoxic and carcinogenic; thus, its level must be strictly controlled. We investigated the concentration of total arsenic and arsenic species: As(III), As(V), MMA, DMA, and AsB in drinking water, surface water, wastewater, and snow collected from the provinces of Wielkopolska, Kujawy-Pomerania, and Lower Silesia (Poland). The total arsenic was analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and arsenic species were analyzed with use of high-performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Obtained results revealed that maximum total arsenic concentration determined in drinking water samples was equal to 1.01 μg L(-1). The highest concentration of total arsenic in surface water, equal to 3778 μg L(-1) was determined in Trująca Stream situated in the area affected by geogenic arsenic contamination. Total arsenic concentration in wastewater samples was comparable to those determined in drinking water samples. However, significantly higher arsenic concentration, equal to 83.1 ± 5.9 μg L(-1), was found in a snow sample collected in Legnica. As(V) was present in all of the investigated samples, and in most of them, it was the sole species observed. However, in snow sample collected in Legnica, more than 97 % of the determined concentration, amounting to 81 ± 11 μg L(-1), was in the form of As(III), the most toxic arsenic species.

  15. Seasonal study of concentration of heavy metals in waters from lower São Francisco River basin, Brazil

    Directory of Open Access Journals (Sweden)

    A. M. Souza

    Full Text Available Abstract In this study we determined the concentration of metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water lower São Francisco River basin, to evaluate the influence of urbanization and industrialization on environmental changes in the water resource. All samples were analyzed using the IUPAC adapted method and processed in an atomic absorption spectrophotometer. The sampling stations located near the industrial areas were influenced by industrialization because they presented higher concentrations of Cd, Cr, Ni and Cu. The other sampled locations showed changes with regard the trace elements probably originating in the soil, like Fe, Zn and Pb. There was a gradual increase in the concentrations of metals, in general, in the period of highest rainfall of the hydrographic network. Overall, except for Zn and Mn, the trace elements exceeded the maximum allowed value established by national legislation (CONAMA. Lower São Francisco River basin has suffered interference from urbanization and industrialization, so awareness programs should be developed so as to control and lessen future problems.

  16. The Seasonal cycle of the Tropical Lower Stratospheric Water Vapor in Chemistry-Climate Models in Comparison with Observations

    Science.gov (United States)

    Wang, X.; Dessler, A. E.

    2017-12-01

    The seasonal cycle is one of the key features of the tropical lower stratospheric water vapor, so it is important that the climate models reproduce it. In this analysis, we evaluate how well the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM) and the Whole Atmosphere Community Climate Model (WACCM) reproduce the seasonal cycle of tropical lower stratospheric water vapor. We do this by comparing the models to observations from the Microwave Limb Sounder (MLS) and the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim (ERAi). We also evaluate if the chemistry-climate models (CCMs) reproduce the key transport and dehydration processes that regulate the seasonal cycle using a forward, domain filling, diabatic trajectory model. Finally, we explore the changes of the seasonal cycle during the 21st century in the two CCMs. Our results show general agreement in the seasonal cycles from the MLS, the ERAi, and the CCMs. Despite this agreement, there are some clear disagreements between the models and the observations on the details of transport and dehydration in the TTL. Finally, both the CCMs predict a moister seasonal cycle by the end of the 21st century. But they disagree on the changes of the seasonal amplitude, which is predicted to increase in the GEOSCCM and decrease in the WACCM.

  17. Relationships between lower tropospheric stability, low cloud cover, and water vapor isotopic composition in the subtropical Pacific

    Science.gov (United States)

    Galewsky, J.

    2017-12-01

    Understanding the processes that govern the relationships between lower tropospheric stability and low-cloud cover is crucial for improved constraints on low-cloud feedbacks and for improving the parameterizations of low-cloud cover used in climate models. The stable isotopic composition of atmospheric water vapor is a sensitive recorder of the balance of moistening and drying processes that set the humidity of the lower troposphere and may thus provide a useful framework for improving our understanding low-cloud processes. In-situ measurements of water vapor isotopic composition collected at the NOAA Mauna Loa Observatory in Hawaii, along with twice-daily soundings from Hilo and remote sensing of cloud cover, show a clear inverse relationship between the estimated inversion strength (EIS) and the mixing ratios and water vapor δ -values, and a positive relationship between EIS, deuterium excess, and Δ δ D, defined as the difference between an observation and a reference Rayleigh distillation curve. These relationships are consistent with reduced moistening and an enhanced upper-tropospheric contribution above the trade inversion under high EIS conditions and stronger moistening under weaker EIS conditions. The cloud fraction, cloud liquid water path, and cloud-top pressure were all found to be higher under low EIS conditions. Inverse modeling of the isotopic data for the highest and lowest terciles of EIS conditions provide quantitative constraints on the cold-point temperatures and mixing fractions that govern the humidity above the trade inversion. The modeling shows the moistening fraction between moist boundary layer air and dry middle tropospheric air 24±1.5% under low EIS conditions is and 6±1.5% under high EIS conditions. A cold-point (last-saturation) temperature of -30C can match the observations for both low and high EIS conditions. The isotopic composition of the moistening source as derived from the inversion (-114±10‰ ) requires moderate

  18. Definition of Greater Gulf Basin Lower Cretaceous and Upper Cretaceous Lower Cenomanian Shale Gas Assessment Unit, United States Gulf of Mexico Basin Onshore and State Waters

    Science.gov (United States)

    Dennen, Kristin O.; Hackley, Paul C.

    2012-01-01

    An assessment unit (AU) for undiscovered continuous “shale” gas in Lower Cretaceous (Aptian and Albian) and basal Upper Cretaceous (lower Cenomanian) rocks in the USA onshore Gulf of Mexico coastal plain recently was defined by the U.S. Geological Survey (USGS). The AU is part of the Upper Jurassic-Cretaceous-Tertiary Composite Total Petroleum System (TPS) of the Gulf of Mexico Basin. Definition of the AU was conducted as part of the 2010 USGS assessment of undiscovered hydrocarbon resources in Gulf Coast Mesozoic stratigraphic intervals. The purpose of defining the Greater Gulf Basin Lower Cretaceous Shale Gas AU was to propose a hypothetical AU in the Cretaceous part of the Gulf Coast TPS in which there might be continuous “shale” gas, but the AU was not quantitatively assessed by the USGS in 2010.

  19. Water-quality conditions during low flow in the lower Youghiogheny River basin, Pennsylvania, October 5-7, 1998

    Science.gov (United States)

    Sams, James I.; Schroeder, Karl T.; Ackman, Terry E.; Crawford, J.K.; Otto, Kim L.

    2001-01-01

    In October 1998, a chemical synoptic survey was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, National Energy Technology Laboratory, in the Lower Youghiogheny River Basin in Pennsylvania to give a snapshot of present (1998) water quality during low-flow conditions. Water samples from 38 sites—12 mainstem sites, 22 tributaries, and 4 mine discharges that discharge directly to the Youghiogheny River—were used to identify sources of contaminants from mining operations. Specific conductance, water temperature, pH, and dissolved oxygen were measured in the field at each site and concentrations of major ions and trace elements were measured in the laboratory.zUnaccounted for gains and losses in streamflow were measured during the study. Unaccounted for losses in streamflow might be attributed to water loss through streambed fractures. Extensive mine tunnels are present in the basin and loss of water to these tunnels seems likely. Unaccounted for gains in streamflow may be from unmeasured tributaries or surface seeps, but most of the gains are suspected to come from artesian flow through fractures in the streambed from underground mine pools. Influent flows of rust-colored water were noted in some river sections.The pH values for all the samples collected during this survey were above 5.8, and most (33 of 38 samples) were above 7.0. Samples from the four mine-discharge sites also had pH values between 6.3 and 6.7. The lowest pH (5.8) was in a tributary, Galley Run. All 38 sampling sites had net alkalinity.The alkalinity load in the Youghiogheny River increased between Connellsville and McKeesport from 35 to 79 tons per day. Above Smithton, the measured alkalinity load in the Lower Youghiogheny River agreed well with the estimated alkalinity load. Below Smithton, measured alkalinity loads in the Lower Youghiogheny River are greater than calculated loads, resulting in unaccounted for gains in alkalinity. These gains are

  20. WATER-QUALITY CONDITIONS DURING LOW FLOW IN THE LOWER YOUGHIOGHENY RIVER BASIN, PENNSYLVANIA, OCTOBER 5-7, 1998; FINAL

    International Nuclear Information System (INIS)

    James I. Sams, III, Karl T. Schroeder; Terry E. Ackman; J. Kent Crawford; Kim L. Otto

    2001-01-01

    In October 1998, a chemical synoptic survey was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, National Energy Technology Laboratory, in the Lower Youghiogheny River Basin in Pennsylvania to give a snap-shot of present (1998) water quality during low-flow conditions. Water samples from 38 sites-12 mainstem sites, 22 tributaries, and 4 mine discharges that discharge directly to the Youghiogheny River-were used to identify sources of contaminants from mining operations. Specific conductance, water temperature, pH, and dissolved oxygen were measured in the field at each site and concentrations of major ions and trace elements were measured in the laboratory. Unaccounted for gains and losses in streamflow were measured during the study. Unaccounted for losses in streamflow might be attributed to water loss through streambed fractures. Extensive mine tunnels are present in the basin and loss of water to these tunnels seems likely. Unaccounted for gains in streamflow may be from unmeasured tributaries or surface seeps, but most of the gains are suspected to come from artesian flow through fractures in the streambed from underground mine pools. Influent flows of rust-colored water were noted in some river sections. The pH values for all the samples collected during this survey were above 5.8, and most (33 of 38 samples) were above 7.0. Samples from the four mine-discharge sites also had pH values between 6.3 and 6.7. The lowest pH (5.8) was in a tributary, Galley Run. All 38 sampling sites had net alkalinity. The alkalinity load in the Youghiogheny River increased between Connellsville and McKeesport from 35 to 79 tons per day. Above Smithton, the measured alkalinity load in the Lower Youghiogheny River agreed well with the estimated alkalinity load. Below Smithton, measured alkalinity loads in the Lower Youghiogheny River are greater than calculated loads, resulting in unaccounted for gains in alkalinity. These gains are

  1. Water Use Efficiency of Cotton and Wheat Crops at Various Management Allowed Depletion in Lower Indus Basin

    Directory of Open Access Journals (Sweden)

    KHALIFA QASIML AGHARI

    2010-10-01

    Full Text Available This paper deals with contemporary irrigation water management of major crops in Lower Indus Basin of Pakistan. Field experiments were conducted to estimate the optimum WUE (Water Use Efficiency for various MAD (Management Allowed Depletion levels including 55, 65 and 75% for cotton crop, and 45, 55 and 65% for wheat crop. The daily actual crop Etca (Evapotranspiration was observed through gypsum blocks and a drainage Lysimeter. The observed seasonal cotton crops ETca in the experiments were 486, 413, and 397 mm for 55, 65, and 75% MAD levels, respectively. Similarly, wheat crops ETca observed were 363, 359, and 332mm for 45, 55, and 65% MAD levels, respectively. The WUE determined in terms of seed-cotton yield per unit of seasonal water use were 6.0, 6.5, and 5.8kg (ha mm-1 The corresponding values of WUE for wheat were 14.1, 15.0 and 13.4kg (ha mm-1. Hence; the highest WUE was achieved with MAD at 65% for cotton and at 55% for wheat.

  2. [Spatial distribution of Tamarix ramosissima aboveground biomass and water consumption in the lower reaches of Heihe River, Northwest China].

    Science.gov (United States)

    Peng, Shou-Zhang; Zhao, Chuan-Yan; Peng, Huan-Hua; Zheng, Xiang-Lin; Xu, Zhong-Lin

    2010-08-01

    Based on the field observation on the Tamarix ramosissima populations in the lower reaches of Heihe River, the relationship models between the aboveground biomass of T. ramosissima and its morphological features (basal diameter, height, and canopy perimeter) were built. In the mean time, the land use/cover of the study area was classified by the decision tree classification with high resolution image (QuickBird), the distribution of T. ramosissima was extracted from classification map, and the morphological feature (canopy perimeter) of T. ramosissima was calculated with ArcGIS 9.2. On the bases of these, the spatial distribution of T. ramosissima aboveground biomass in the study area was estimated. Finally, the spatial distribution of the water consumption of T. ramosissima in the study area was calculated by the transpiration coefficient (300) and the aboveground biomass. The results showed that the aboveground biomass of T. ramosissima was 69644.7 t, and the biomass per unit area was 0.78 kg x m(-2). Spatially, the habitats along the banks of Heihe River were suitable for T. ramosissima, and thus, this tree species had a high biomass. The total amount of water consumption of T. ramosissima in the study area was 2.1 x 10(7) m3, and the annual mean water consumption of T. ramosissima ranged from 30 mm to 386 mm.

  3. Mortality table construction

    Science.gov (United States)

    Sutawanir

    2015-12-01

    Mortality tables play important role in actuarial studies such as life annuities, premium determination, premium reserve, valuation pension plan, pension funding. Some known mortality tables are CSO mortality table, Indonesian Mortality Table, Bowers mortality table, Japan Mortality table. For actuary applications some tables are constructed with different environment such as single decrement, double decrement, and multiple decrement. There exist two approaches in mortality table construction : mathematics approach and statistical approach. Distribution model and estimation theory are the statistical concepts that are used in mortality table construction. This article aims to discuss the statistical approach in mortality table construction. The distributional assumptions are uniform death distribution (UDD) and constant force (exponential). Moment estimation and maximum likelihood are used to estimate the mortality parameter. Moment estimation methods are easier to manipulate compared to maximum likelihood estimation (mle). However, the complete mortality data are not used in moment estimation method. Maximum likelihood exploited all available information in mortality estimation. Some mle equations are complicated and solved using numerical methods. The article focus on single decrement estimation using moment and maximum likelihood estimation. Some extension to double decrement will introduced. Simple dataset will be used to illustrated the mortality estimation, and mortality table.

  4. CERN Table Tennis Club

    CERN Multimedia

    CERN Table Tennis Club

    2014-01-01

    CERN Table Tennis Club Announcing CERN 60th Anniversary Table Tennis Tournament to take place at CERN, from July 1 to July 15, 2014   The CERN Table Tennis Club, reborn in 2008, is encouraging people at CERN to take more regular exercise. This is why the Club, thanks to the strong support of the CERN Staff Association, installed last season a first outdoor table on the terrace of restaurant # 1, and will install another one this season on the terrace of Restaurant # 2. Table tennis provides both physical exercise and friendly social interactions. The CERN Table Tennis club is happy to use the unique opportunity of the 60th CERN anniversary to promote table tennis at CERN, as it is a game that everybody can easily play, regardless of level. Table tennis is particularly well suited for CERN, as many great physicists play table tennis, as you might already know: “Heisenberg could not even bear to lose a game of table tennis”; “Otto Frisch played a lot of table tennis;...

  5. Regional analysis of groundwater phosphate concentrations under acidic sandy soils: Edaphic factors and water table strongly mediate the soil P-groundwater P relation.

    Science.gov (United States)

    Mabilde, Lisa; De Neve, Stefaan; Sleutel, Steven

    2017-12-01

    Historic long-term P application to sandy soils in NW-Europe has resulted in abundant sorption, saturation and eventually leaching of P from soil to the groundwater. Although many studies recognize the control of site-specific factors like soil texture and phosphate saturation degree (PSD), the regional-scaled relevance of effects exerted by single factors controlling P leaching is unclear. Very large observational datasets of soil and groundwater P content are furthermore required to reveal indirect controls of soil traits through mediating soil variables. We explored co-variation of phreatic groundwater orthophosphate (o-P) concentration and soil factors in sandy soils in Flanders, Belgium. Correlation analyses were complemented with an exploratory model derived using 'path analysis'. Data of oxalate-extractable Al, Fe, P and pH KCl , phosphate sorption capacity (PSC) and PSD in three depth layers (0-30, 30-60, 60-90 cm), topsoil SOC, % clay and groundwater depth (fluctuation) were interpolated to predict soil properties on exact locations of a very extensive net of groundwater monitoring wells. The mean PSD was only poorly correlated to groundwater o-P concentration, indicating the overriding control of other factors in the transport of P to the groundwater. A significant (P soil pH and groundwater table depth than by PSD indicates the likely oversimplification of the latter index to measure the long-term potential risk of P leaching. Accounting for controls on leaching not included in PSD via an alternative index, however, seems problematic as in Flanders for example groundwater o-P turned out to be higher in finer textured soils or soils with higher pedogenic Fe content, probably because of their lower pedogenic Al content and higher soil pH. Path analysis of extensive soil and groundwater datasets seems a viable way to identify prime local determinants of soil P leaching and could be further on used for 'ground-truthing' more complex P-migration simulation

  6. Pros and Cons of Adopting Water-Wise Approaches in the Lower Reaches of the Amu Darya: A Socio-Economic View

    OpenAIRE

    Bekchanov; Lamers; Martius

    2010-01-01

    The increased frequency of water shortages parallel to growing demands for agricultural commodities in the lower reaches of the Amu Darya River, Central Asia, calls for improving the system-level water use efficiency, by using interventions at the field level. Despite the existence of various best practices of effective water use (defined here as “water-wise options”), they are not widely adopted by farmers owing to high initial costs of investment and lack of the necessary knowledge and skil...

  7. TABLE TENNIS CLUB

    CERN Document Server

    TABLE TENNIS CLUB

    2010-01-01

    2010 CERN Table Tennis Tournament The CERN Table Tennis Club organizes its traditional CERN Table Tennis Tournament, at the Meyrin club, 2 rue de livron, in Meyrin, Saturday August 21st, in the afternoon. The tournament is open to all CERN staff, users, visitors and families, including of course summer students. See below for details. In order to register, simply send an E-mail to Jean-Pierre Revol (jean-pierre.revol@cern.ch). You can also download the registration form from the Club Web page (http://www.cern.ch/tabletennis), and send it via internal mail. Photo taken on August 22, 2009 showing some of the participants in the 2nd CERN Table Tennis tournament. INFORMATION ON CERN TABLE TENNIS CLUB CERN used to have a tradition of table tennis activities at CERN. For some reason, at the beginning of the 1980’s, the CERN Table Tennis club merged with the Meyrin Table Tennis club, a member of the Association Genevoise de Tennis de Table (AGTT). Therefore, if you want to practice table tennis, you...

  8. Monitoring and modeling the fate of commonly used pesticides in surface water of the Lower Mekong Delta

    Science.gov (United States)

    van Toan, Pham; Sebesvari, Zita; Loan, Vo Phuong Hong; Renaud, Fabrice

    2010-05-01

    Introduction: The Lower Mekong Delta, one of the largest agricultural areas in Southeast Asia, has been reported to be increasingly polluted by agrochemicals since the beginning of the transformation processes in Vietnamese economy and specifically in the agricultural sector in 1986 (MRCS, 2007; Dasgupta et al., 2005; Dung, 2003; Phuong, 2003). Although pesticides have contributed significantly to enhancing agricultural productivity, these agrochemicals also have created risks to human health and environment (Margni, 2001; Phuong, 2003; Dasgupta et al., 2005) and lead to value loss of water resources (Phuong, 2003). While prohibited persistent organic pollutants such as HCHs and DDTs, were monitored and still detected in the Lower Mekong Delta in recent studies (Minh et al., 2007, Carvalho et al., 2008) little data exist on water pollution by recently used pesticides in the Delta. Aiming to fill this information gap, a study comprising three components was set up at two study sites of the Delta. Pesticide use and management was investigated through surveys and participatory rural appraisals with farmers; pesticide residue concentrations were determined in field outflows, connected irrigation canals and in drinking water and finally pesticide fate was predicted by using a coupled MIKE 11/ MIKE SHE model. This abstract focuses on the work done in the field of pesticide monitoring. The western study site (An Long Commune, Dong Thap province) represented an agricultural pattern with two intensive paddy rice crops per year and was heavily affected by flood in the rainy season. The second site located in the central part of the Delta (Ba Lang ward, Can Tho City) was characterized by a mix of paddy rice, vegetables and fruit trees. Fifteen pesticide compounds (buprofezin, butachlor, cypermethrin, difenozonazol, α-endosulfan, β-endosulfan, endosulfan-sulfate, fenobucarb, fipronil, hexaconazol, isoprothiolane, pretilachlor, profenofos, propanil, and propiconazol) were

  9. Randomised controlled trial of the cost-effectiveness of water-based therapy for lower limb osteoarthritis.

    Science.gov (United States)

    Cochrane, T; Davey, R C; Matthes Edwards, S M

    2005-08-01

    To determine the efficacy of community water-based therapy for the management of lower limb osteoarthritis (OA) in older patients. A pre-experimental matched-control study was used to estimate efficacy of water-based exercise treatment, to check design assumptions and delivery processes. The main study was a randomised controlled trial of the effectiveness of water-based exercise (treatment) compared with usual care (control) in older patients with hip and/or knee OA. The latter was accompanied by an economic evaluation comparing societal costs and consequences of the two treatments. Water exercise was delivered in public swimming pools in the UK. Physical function assessments were carried out in established laboratory settings. 106 patients (93 women, 13 men) over the age of 60 years with confirmed hip and/or knee OA took part in the preliminary study. A similar, but larger, group of 312 patients (196 women, 116 men) took part in the main study, randomised into control (159) and water exercise (153) groups. Control group patients received usual care with quarterly semi-structured telephone interview follow-up only. The intervention in the main study lasted for 1 year, with a further follow-up period of 6 months. Pain score on the Western Ontario and McMaster Universities OA index (WOMAC). Additional outcome measures were included to evaluate effects on quality of life, cost-effectiveness and physical function measurements. Short-term efficacy of water exercise in the management of lower limb OA was confirmed, with effect sizes ranging from 0.44 [95% confidence interval (CI) 0.03 to 0.85] on WOMAC pain to 0.76 (95% CI 0.33 to 1.17) on WOMAC physical function. Of 153 patients randomised to treatment, 82 (53.5%) were estimated to have complied satisfactorily with their treatment at the 1-year point. This had declined to 28 (18%) by the end of the 6-month follow-up period, during which support for the intervention had been removed and those wishing to continue

  10. Hydrophobic-modified nano-cellulose fiber/PLA biodegradable composites for lowering water vapor transmission rate (WVTR) of paper.

    Science.gov (United States)

    Song, Zhaoping; Xiao, Huining; Zhao, Yi

    2014-10-13

    New biodegradable nanocomposites have been successfully prepared by incorporating modified nano-cellulose fibers (NCF) in a biodegradable polylactic acid (PLA) matrix in this work. The hydrophobic-modified NCF was obtained by grafting hydrophobic monomers on NCF to improve the compatibility between NCF and PLA during blending. The resulting NCF/PLA composites were then applied on paper surface via a cast-coating process in an attempt to reduce the water vapor transmission rate (WVTR) of paper. The WVTR tests, conducted under various testing conditions and with different coating weights, demonstrated that the modified NCF/PLA composites coating played a critical role in lowering WVTR of paper. The lowest WVTR value was 34 g/m(2)/d, which was obtained with an addition of 1% of modified NCF to PLA and the composites coating weight at 40 g/m(2) and substantially lower than the control value at 1315 g/m(2)/d. The paper coated with the modified biodegradable composite is promising as green-based packaging materials. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Spatiotemporal Variation and Risk Assessment of Pesticides in Water of the Lower Catchment Basin of Acheloos River, Western Greece

    Science.gov (United States)

    Stamatis, Nikolaos; Hela, Dimitra; Triantafyllidis, Vassilios; Konstantinou, Ioannis

    2013-01-01

    A three-year monitoring survey (March 2005–February 2008) was conducted to investigate, on monthly basis, the presence of thirty pesticides belonging to various categories and metabolites, in Acheloos River (Western Greece), one of the most important water resources in Greece. Six sampling stations along the river were established. Water analyses were performed using solid-phase extraction combined with gas chromatography with flame thermionic detector and mass spectrometry. Statistical analysis using one-way ANOVA and Duncan's multiple range test (P < 0.05) was used to compare annual mean concentrations of pesticides, seasonal and spatial distribution. In general, the highest mean concentrations of the pesticides were recorded at the three stations downstream. The greatest average concentrations were determined during spring and summer in agreement with the pesticide application period. The observed lower concentrations after 2006 reflect the land-use change because of the elimination of tobacco, the main cultivation of the area for many decades. The compounds most frequently detected were diazinon (78.6%), DEA (69.3%), and fenthion (52.6%). Environmental risk assessment using risk quotient (RQ) approach showed high risk for six insecticides in 2005 and one in 2007. A compliance with the European Environmental Quality Standards (EQS) was observed for the priority pesticides. PMID:24453814

  12. Concentrations of nitrate in drinking water in the lower Yakima River Basin, Groundwater Management Area, Yakima County, Washington, 2017

    Science.gov (United States)

    Huffman, Raegan L.

    2018-05-29

    The U.S. Geological Survey, in cooperation with the lower Yakima River Basin Groundwater Management Area (GWMA) group, conducted an intensive groundwater sampling collection effort of collecting nitrate concentration data in drinking water to provide a baseline for future nitrate assessments within the GWMA. About every 6 weeks from April through December 2017, a total of 1,059 samples were collected from 156 wells and 24 surface-water drains. The domestic wells were selected based on known location, completion depth, ability to collect a sample prior to treatment on filtration, and distribution across the GWMA. The drains were pre-selected by the GWMA group, and further assessed based on ability to access sites and obtain a representative sample. More than 20 percent of samples from the domestic wells and 12.8 percent of drain samples had nitrate concentrations that exceeded the maximum contaminant level (MCL) of 10 milligrams per liter established by the U.S. Environmental Protection Agency. At least one nitrate concentration above the MCL was detected in 26 percent of wells and 33 percent of drains sampled. Nitrate was not detected in 13 percent of all samples collected.

  13. Dynamic behaviour of natural oil droplets through the water column in deep-water environment: the case of the Lower Congo Basin

    Science.gov (United States)

    Jatiault, R.; Dhont, D.; Loncke, L.; Durrieu De Madron, X.; Dubucq, D.; Channelliere, C.; Bourrin, F.

    2017-12-01

    Key words: Hydrocarbon seepage, Oil Slick, Lower Congo Basin, Underwater deflection, Deep-water Pockmark, Ascent speedThe space-borne imagery provides a significant means to locate active oil seeps and to estimate the expelled volume in the marine environment. The analysis of numerous overlapping satellite images revealed an abundant volume of 4400 m3 of oil naturally reaching the sea surface per year, expelled from more than a hundred seep sites through the Lower Congo Basin. The active seepage area is located in the distal compressional province of the basin where salt napes and squeezed diapirs. The integration of current data was used to link accurately sea surface manifestations of natural oil leakages with active fluid flow features on the seafloor. A mooring with ADCPs (Acoustic Doppler Current Profilers) distributed throughout the water column provided an efficient calibration tool to evaluate the horizontal deflection of oil droplets. Using a Eulerian propagation model that considered a range of probable ascent speeds, we estimated the oil migration pathways through the water column using two different approaches. The first approach consisted in simulating the backwards trajectory of oil droplets using sea surface oil slicks locations and concomitant current measurements. The second method analyzed the spatial spreading of the surfacing signatures of natural oil slicks based on 21 years of satellite observations. The location of the surfacing points of oil droplets at the sea surface is restricted to a circle of 2.5 km radius around the release point at the seafloor. Both approaches provided a range of ascent speeds of oil droplets between 3 to 8 cm.s-1. The low deflection values validate the near-vertical links between the average surfacing area of oil slicks at the sea surface with specific seafloor disturbances (i.e. pockmarks or mounds) known to expel fluids.

  14. A Probabilistic Assessment of Threats to Surface Water Resources in Watersheds of the Lower Colorado River Basin

    Science.gov (United States)

    Murphy, K. W.; Ellis, A. W.

    2012-12-01

    The Salt and Verde River watersheds in the Lower Colorado River Basin are a very important surface water resource in the Southwest United States. Their runoff is captured by a downstream reservoir system serving approximately 40% of the water demand and providing hydroelectric power to the Phoenix, Arizona area. Concerns have been expressed over the risks associated with their highly variable climate dependencies under the realization that the short, historical stream flow record was but one of many possible temporal and volumetric outcome sequences. A characterization of the possible range of flow deficits arising from natural variability beyond those evident in the instrumental record can facilitate sustainability planning as well as adaptation to future climate change scenarios. Methods were developed for this study to generate very long seasonal time series of net reservoir inflows by Monte Carlo simulations of the Salt and Verde watersheds which can be analyzed for detailed probabilistic insights. Other efforts to generate stochastic flow representations for impact assessments have been limited by normality distribution assumptions, inability to represent the covariance of flow contributions from multiple watersheds, complexities of different seasonal origins of precipitation and runoff dependencies, and constraints from spectral properties of the observational record. These difficulties were overcome in this study through stationarity assessments and development of joint probability distributions with highly skewed discrete density functions characteristic of the different watershed-season behaviors derived from a 123 year record. As well, methods of introducing season-to-season correlations owing to antecedent precipitation runoff efficiency enhancements have been incorporated. Representative 10,000 year time series have been stochastically generated which reflect a full range of temporal variability in flow volume distributions. Extreme value statistical

  15. Standard Reference Tables -

    Data.gov (United States)

    Department of Transportation — The Standard Reference Tables (SRT) provide consistent reference data for the various applications that support Flight Standards Service (AFS) business processes and...

  16. Evaluation of a computer model to simulate water table response to subirrigation Avaliação de um modelo computacional para simular a resposta do lençol freático à subirrigação

    Directory of Open Access Journals (Sweden)

    Jadir Aparecido Rosa

    2002-12-01

    Full Text Available The objective of this work was to evaluate the water flow computer model, WATABLE, using experimental field observations on water table management plots from a site located near Hastings, FL, USA. The experimental field had scale drainage systems with provisions for subirrigation with buried microirrigation and conventional seepage irrigation systems. Potato (Solanum tuberosum L. growing seasons from years 1996 and 1997 were used to simulate the hydrology of the area. Water table levels, precipitation, irrigation and runoff volumes were continuously monitored. The model simulated the water movement from a buried microirrigation line source and the response of the water table to irrigation, precipitation, evapotranspiration, and deep percolation. The model was calibrated and verified by comparing simulated results with experimental field observations. The model performed very well in simulating seasonal runoff, irrigation volumes, and water table levels during crop growth. The two-dimensional model can be used to investigate different irrigation strategies involving water table management control. Applications of the model include optimization of the water table depth for each growth stage, and duration, frequency, and rate of irrigation.O objetivo deste trabalho foi avaliar o modelo computacional WATABLE usando-se dados de campo obtidos em uma área experimental em manejo de lençol freático, localizada em Hastings, FL, EUA. Na área experimental, estavam instalados um sistema de drenagem e sistemas de irrigação por subsuperfície com irrigação localizada e por canais. Ciclos de cultivo de batata (Solanum tuberosum L., nos anos de 1996 e 1997, foram usados para a simulação da hidrologia da área. Profundidades do lençol freático, chuvas, irrigação e escorrimento superficial foram monitorados constantemente. O modelo simulou o movimento da água a partir de uma linha de irrigação localizada enterrada, e a resposta do nível do len

  17. Surface-water-quality assessment of the lower Kansas River basin, Kansas and Nebraska; results of investigations, 1987-90

    Science.gov (United States)

    Helgesen, J.O.

    1995-01-01

    Surface-water-quality conditions and trends were assessed in the lower Kansas River Basin, which drains about 15,300 square miles of mainly agricultural land in southeast Nebraska and northeast Kansas. On the basis of established water-quality criteria, most streams in the basin were suitable for uses such as public-water supply, irrigation, and maintenance of aquatic life. However, most concerns identified from a previous analysis of available data through 1986 are substantiated by analysis of data for May 1987 through April 1990. Less-than-normal precipitation and runoff during 1987-90 affected surface-water quality and are important factors in the interpretation of results.Dissolved-solids concentrations in the main stem Kansas River during May 1987 through April 1990 commonly exceeded 500 milligrams per liter, which may be of concern for public-water supplies and for the irrigation of sensitive crops. Large concentrations of chloride in the Kansas River are derived from ground water discharging in the Smoky Hill River Basin west of the study unit. Trends of increasing concentrations of some dissolved major ions were statistically significant in the northwestern part of the study unit, which could reflect substantial increases in irrigated acreage.The largest concentrations of suspended sediment in streams during May 1987 through April 1990 were associated with high-density cropland in areas of little local relief and medium-density irrigated cropland in more dissected areas. The smallest concentrations were measured downstream from large reservoirs and in streams draining areas having little or no row-crop cultivation. Mean annual suspended-sediment transport rates in the main stem Kansas River increased substantially in the downstream direction. No conclusions could be reached concerning the relations of suspended-sediment transport, yields, or trends to natural and human factors.The largest sources of nitrogen and phosphorus in the study unit were fertilizer

  18. High temporal resolution modeling of the impact of rain, tides, and sea level rise on water table flooding in the Arch Creek basin, Miami-Dade County Florida USA.

    Science.gov (United States)

    Sukop, Michael C; Rogers, Martina; Guannel, Greg; Infanti, Johnna M; Hagemann, Katherine

    2018-03-01

    Modeling of groundwater levels in a portion of the low-lying coastal Arch Creek basin in northern Miami-Dade County in Southeast Florida USA, which is subject to repetitive flooding, reveals that rain-induced short-term water table rises can be viewed as a primary driver of flooding events under current conditions. Areas below 0.9m North American Vertical Datum (NAVD) elevation are particularly vulnerable and areas below 1.5m NAVD are vulnerable to exceptionally large rainfall events. Long-term water table rise is evident in the groundwater data, and the rate appears to be consistent with local rates of sea level rise. Linear extrapolation of long-term observed groundwater levels to 2060 suggest roughly a doubling of the number of days when groundwater levels exceed 0.9m NAVD and a threefold increase in the number of days when levels exceed 1.5m NAVD. Projected sea level rise of 0.61m by 2060 together with increased rainfall lead to a model prediction of frequent groundwater-related flooding in areas1.5m NAVD and widespread flooding of the area in the past. Tidal fluctuations in the water table are predicted to be more pronounced within 600m of a tidally influenced water control structure that is hydrodynamically connected to Biscayne Bay. The inland influence of tidal fluctuations appears to increase with increased sea level, but the principal driver of high groundwater levels under the 2060 scenario conditions remains groundwater recharge due to rainfall events. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. A nonpolar, nonamphiphilic molecule can accelerate adsorption of phospholipids and lower their surface tension at the air/water interface.

    Science.gov (United States)

    Nguyen, Phuc Nghia; Trinh Dang, Thuan Thao; Waton, Gilles; Vandamme, Thierry; Krafft, Marie Pierre

    2011-10-04

    The adsorption dynamics of a series of phospholipids (PLs) at the interface between an aqueous solution or dispersion of the PL and a gas phase containing the nonpolar, nonamphiphilic linear perfluorocarbon perfluorohexane (PFH) was studied by bubble profile analysis tensiometry. The PLs investigated were dioctanoylphosphatidylcholine (DiC(8)-PC), dilaurylphosphatidylcholine, dimyristoylphosphatidylcholine, and dipalmitoylphosphatidylcholine. The gas phase consisted of air or air saturated with PFH. The perfluorocarbon gas was found to have an unexpected, strong effect on both the adsorption rate and the equilibrium interfacial tension (γ(eq)) of the PLs. First, for all of the PLs, and at all concentrations investigated, the γ(eq) values were significantly lower (by up to 10 mN m(-1)) when PFH was present in the gas phase. The efficacy of PFH in decreasing γ(eq) depends on the ability of PLs to form micelles or vesicles in water. For vesicles, it also depends on the gel or fluid state of the membranes. Second, the adsorption rates of all the PLs at the interface (as assessed by the time required for the initial interfacial tension to be reduced by 30%) are significantly accelerated (by up to fivefold) by the presence of PFH for the lower PL concentrations. Both the surface-tension reducing effect and the adsorption rate increasing effect establish that PFH has a strong interaction with the PL monolayer and acts as a cosurfactant at the interface, despite the absence of any amphiphilic character. Fitting the adsorption profiles of DiC(8)-PC at the PFH-saturated air/aqueous solution interface with the modified Frumkin model indicated that the PFH molecule lay horizontally at the interface. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Rapid movement of wastewater from on-site disposal systems into surface waters in the lower Florida Keys

    Science.gov (United States)

    Paul, John H.; McLaughlin, Molly R.; Griffin, Dale W.; Lipp, Erin K.; Stokes, Rodger; Rose, Joan B.

    2000-01-01

    Viral tracer studies have been used previously to study the potential for wastewater contamination of surface marine waters in the Upper and Middle Florida Keys. Two bacteriophages, the marine bacteriophage φHSIC and the Salmonella phage PRD1, were used as tracers in injection well and septic tank studies in Saddlebunch Keys of the Lower Florida Keys and in septic tank studies in Boot Key Harbor, Marathon, of the Middle Keys. In Boot Key Harbor, both phages were detected in a canal adjacent to the seeded septic tank within 3 h 15 min of the end of the seed period. The tracer was then detected at all sampling sites in Boot Key Harbor, including one on the opposite side of U. S. Highway 1 in Florida Bay, and at an Atlantic Ocean beach outside Boot Key Harbor. Rates of migration based on first appearance of the phage ranged from 1.7 to 57.5 m h-1. In Saddlebunch Keys, φHSIC and PRD1 were used to seed a residential septic tank and a commercial injection well. The septic tank tracer was not found in any surface water samples. The injection well tracer was first detected at a site most distant from the seed site, a channel that connected Sugarloaf Sound with the Atlantic Ocean. The rate of tracer migration from the injection well to this channel ranged from 66.8 to 141 m h-1. Both tracer studies showed a rapid movement of wastewater from on-site sewage treatment and disposal systems in a southeasterly direction toward the reef tract and Atlantic Ocean, with preferential movement through tidal channels. These studies indicate that wastewater disposal systems currently in widespread use in the Florida Keys can rapidly contaminate the marine environment.

  1. Disponibilidade de água em pomar de citros submetido a poda e subsolagem em latossolo amarelo dos tabuleiros costeiros Water availability in citros orchard, under prunning and subsoiling, on yellow latosol of coastal table land

    Directory of Open Access Journals (Sweden)

    Laercio Duarte Souza

    2004-04-01

    Full Text Available Um pomar de laranja 'Baianinha' enxertada sobre limão 'Cravo' com 10 anos de idade, recebeu, neste período, práticas culturais de roçadeira no inverno e grade no verão, com três capinas manuais na linha por ano. Instalado em Latossolo Amarelo, nos Tabuleiros Costeiros, apresentava problemas de fitossanidade e produtividade, oriundos do impedimento ao desenvolvimento de raízes e exploração do solo e da água, ocasionados pelas camadas coesas características destes solos. Com o objetivo de aumentar a disponibilidade de água no solo para as plantas, aplicaram-se tratamentos de subsolagem, em interação com diferentes sistemas de poda da parte aérea. Realizaram-se uma amostragem de parâmetros físicos e químicos do solo, e um monitoramento da água nas profundidades de 0,30; 0,50; 0,70; 0,90; 1,10; 1,30 e 1,50 m com sonda de nêutrons, no período de dois anos ( 1º março/96 a 1º março/98, com duas repetições, em leituras semanais. As melhores respostas foram obtidas com os tratamentos subsolados sem poda e com poda leve. O tratamento subsolado com poda brusca apresentou as maiores deficiências de água disponível no solo, superando, inclusive, a testemunha.A ten years old orchard of orange 'Baianinha' grafted on lemon 'Cravo' was submitted, to cultural practices of mower in the winter and grating in the summer, with three hand weedings, within crop line, a year. The work was carried out in a Yellow Latosol in the Coastal Table Land ecosystem. The orchard presented phytopathological and production problems, which were attributed to the impediment of the development of roots and storage of water, caused by the cohesive layers, characteristics of these soils. This study was to increase the water availability to the plants by treatments with subsoiling combined with different pruning systems. Physical and chemical parameters of the soil were evaluated and the behavior of the water, in the depths of 0,30; 0,50; 0,70; 0,90; 1,10; 1

  2. The Living Periodic Table

    Science.gov (United States)

    Nahlik, Mary Schrodt

    2005-01-01

    To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

  3. Qualification of the calculational methods of the fluence in the pressurised water reactors. Improvement of the cross sections treatment by the probability table method

    International Nuclear Information System (INIS)

    Zheng, S.H.

    1994-01-01

    It is indispensable to know the fluence on the nuclear reactor pressure vessel. The cross sections and their treatment have an important rule to this problem. In this study, two ''benchmarks'' have been interpreted by the Monte Carlo transport program TRIPOLI to qualify the calculational method and the cross sections used in the calculations. For the treatment of the cross sections, the multigroup method is usually used but it exists some problems such as the difficulty to choose the weighting function and the necessity of a great number of energy to represent well the cross section's fluctuation. In this thesis, we propose a new method called ''Probability Table Method'' to treat the neutron cross sections. For the qualification, a program of the simulation of neutron transport by the Monte Carlo method in one dimension has been written; the comparison of multigroup's results and probability table's results shows the advantages of this new method. The probability table has also been introduced in the TRIPOLI program; the calculational results of the iron deep penetration benchmark has been improved by comparing with the experimental results. So it is interest to use this new method in the shielding and neutronic calculation. (author). 42 refs., 109 figs., 36 tabs

  4. Effect of the walking speed to the lower limb joint angular displacements, joint moments and ground reaction forces during walking in water.

    Science.gov (United States)

    Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-ichiro; Nakazawa, Kimitaka; Akai, Masami

    2004-06-17

    The purpose of this study was to compare the changes in ground reaction forces (GRF), joint angular displacements (JAD), joint moments (JM) and electromyographic (EMG) activities that occur during walking at various speeds in water and on land. Fifteen healthy adults participated in this study. In the water experiments, the water depth was adjusted so that body weight was reduced by 80%. A video-motion analysis system and waterproof force platform was used to obtain kinematics and kinetics data and to calculate the JMs. Results revealed that (1) the anterior-posterior GRF patterns differed between walking in water and walking on land, whereas the medio-lateral GRF patterns were similar, (2) the JAD patterns of the hip and ankle were similar between water- and land-walking, whereas the range of motion at the knee joint was lower in water than on land, (3) the JMs in all three joints were lower in water than on land throughout the stance phase, and (4) the hip joint extension moment and hip extensor muscle EMG activity were increased as walking speed increase during walking in water. Rehabilitative water-walking exercise could be designed to incorporate large-muscle activities, especially of the lower-limb extensor muscles, through full joint range of motion and minimization of joint moments.

  5. Evaluation of juvenile salmonid bypass facilities and passage at water diversions on the lower Umatilla River. Final report

    International Nuclear Information System (INIS)

    Cameron, W.A.; Knapp, S.M.; Carmichael, R.W.

    1997-07-01

    Outdated juvenile and adult fish passage facilities were recently reconstructed at the five major irrigation dams on the lower Umatilla River, Oregon to meet National marine Fisheries Service (NMFS) design standards. Changes in design at juvenile fish bypass facilities included reduced mesh size on the rotating drum screens, larger screening area, a more oblique orientation of the drum screens to canal flow, improved screen seals, replacement of bypass portals with vertical slot bypass channels, and increased bypass pipe diameters. Weir-and-pool adult fish ladders and jump pools were replaced with vertical-slot ladders. From 1991--1995, they investigated injury and travel rate of juvenile fish moving through the facilities, and efficiency of screens in preventing fish entry into the canals. Water velocities in front of canal screens, at bypass channel entrances, and at ladder diffusers were measured to assess adherence to NMFS criteria and identify hydraulic patterns. Biological evaluations were conducted by releasing and recapturing marked yearling summer steelhead (Oncorhynchus mykiss), yearling spring chinook salmon (O. tshawytscha), and subyearling fall chinook salmon (O. tshawytscha) in varying locations within the fish passage facilities

  6. Massive Lumbar Disk Herniation Following "Therapeutic" Water Boiling of the Lower Extremities: Case Report and Literature Review.

    Science.gov (United States)

    Spallone, Aldo; Çelniku, Megi

    2017-01-01

    Legs burning for treating lumbar radicular pain are still in use nowadays in low socioeconomical environments. They are dangerous as the case we report shows clearly. A 49-year-old man came to our attention with severe flaccid paraparesis occurred 10 days before, almost immediately after he had immersed his legs in boiling water to treat his severe left lumbocrural pain. This was known to be due to a right L3/4 herniated disk diagnosed by magnetic resonance imaging. At the examination he showed severe motor paresis and absent reflexes of his lower limbs, while crural pain was mild and sensation and urinary function were unaffected. The results of his neurologic examination led us to suspect an acute motor axon degeneration related to thermal shock. Lumbar magnetic resonance imaging, performed before the planned electromyogram as an exception to the established routine, showed instead a giant 5- × 5.5-cm, herniated disk compressing the dural sac at L3. Prompt surgical decompression led to rapid improvement. We discuss here the pathophysiology of this unusual case and point out how medieval practices for treating sciatica-like pain are not only unjustified from a medical viewpoint but also potentially dangerous. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. The Effectiveness of Enterprises of the Lower Volga Water Transport on the Eve of World War II

    Directory of Open Access Journals (Sweden)

    SIDOROV S.G.

    2014-06-01

    Full Text Available From the navigation of 1940 the rate of traffic on Volga as well as throughout the country was slowing down. Transportations in the 1930s were carried out in hard conditions. While freight and passenger traffic increased annually, propelled fleet declined. Fleet replenishment, as well as its decline mainly occurred due to redistribution of old vessels between shipping companies but not due to the building of new ships. Besides, during the pre-war period the USSR had the acute problem of providing the river transport with professionals. The main difficulty lies in the inability to supply fleet, routes and coastal enterprises with qualified personnel that during the 1930s was not numerous. The situation with unskilled labor force was no better. It was complicated by the huge turnover and disproportionate distribution of workers between shipping companies and within them. The importance of training qualified specialists for working in ports and marines was underestimated. Low rate of technical reconstruction due to insufficient investments reduced the efficiency of water transport enterprises. The Lower Volga river fleet and the shore facilities were not sufficiently developed. All these difficulties had influence on the rate of cargo and passenger transportation.

  8. Working with Decision Makers to Improve Energy-Water System Resiliency in the Lower Hudson River Basin

    Science.gov (United States)

    Fellows, J. D.; Schoonen, M. A.; Pullen, J.; González, J. E.; Saleh, F.; Bhatt, V.

    2017-12-01

    Nearly half of the 180 million people living in the eastern U.S. reside in coastal watershed or shoreline counties. The population density of these areas continues to increase, driving an increase in energy-water (EW) system demand and expansion of critical infrastructure. Along with population, these areas are also being stressed by environmental and technology stresses, including climate change. We have been working with decision makers in the Lower Hudson River Basin (LHRB) to develop the tools and data needed to better understand and improve the resiliency of LHRB EW systems facing these kinds of stresses. The LHRB represents: 1) a coastal environment subject to sea level rise that is among the fastest in the East; 2) one of the steepest gradients in population density in the US, with Manhattan the most densely populated coastal county in the nation; 3) a EWN infrastructure serving the largest metropolitan area in the US and the financial center of the world; 4) a history of environmental impacts, ranging from heatwaves, hurricanes to localized storms, that can be used to hindcast; and 5) a wealth of historic and real-time data, extensive monitoring facilities and existing specific sector models that can be leveraged. This presentation will focus on the lessons learned working with the LHRB decision makers.

  9. Water-quality characteristics of quaternary unconsolidated-deposit aquifers and lower tertiary aquifers of the Bighorn Basin, Wyoming and Montana, 1999-2001

    Science.gov (United States)

    Bartos, Timothy T.; Eddy-Miller, Cheryl A.; Norris, Jody R.; Gamper, Merry E.; Hallberg, Laura L.

    2004-01-01

    As part of the Yellowstone River Basin National Water Quality Assessment study, ground-water samples were collected from Quaternary unconsolidated-deposit and lower Tertiary aquifers in the Bighorn Basin of Wyoming and Montana from 1999 to 2001. Samples from 54 wells were analyzed for physical characteristics, major ions, trace elements, nutrients, dissolved organic carbon, radionuclides, pesticide compounds, and volatile organic compounds (VOCs) to evaluate current water-quality conditions in both aquifers. Water-quality samples indicated that waters generally were suitable for most uses, and that natural conditions, rather than the effects of human activities, were more likely to limit uses of the waters. Waters in both types of aquifers generally were highly mineralized, and total dissolved-solids concentrations frequently exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) of 500 milligrams per liter (mg/L). Because of generally high mineralization, waters from nearly one-half of the samples from Quaternary aquifers and more than one-half of the samples from lower Tertiary aquifers were not classified as fresh (dissolved-solids concentration were not less than 1,000 mg/L). The anions sulfate, fluoride, and chloride were measured in some ground-water samples at concentrations greater than SMCLs. Most waters from the Quaternary aquifers were classified as very hard (hardness greater than 180 mg/L), but hardness varied much more in waters from the lower Tertiary aquifers and ranged from soft (less than 60 mg/L) to very hard (greater than 180 mg/L). Major-ion chemistry varied with dissolved-solids concentrations. In both types of aquifers, the predominant anion changes from bicarbonate to sulfate with increasing dissolved-solids concentrations. Samples from Quaternary aquifers with fresh waters generally were calcium-bicarbonate, calcium-sodium-bicarbonate, and calcium-sodium-sulfate-bicarbonate type waters, whereas

  10. Development of a higher capacity, lower pressure drop steam/water separator with reduced primary-to-secondary spacing

    International Nuclear Information System (INIS)

    Pruster, W.P.; Kidwell, J.H.; Eaton, A.M.; Wall, J.R.

    1985-01-01

    The goal of this development effort was to double the steam flow capacity of an existing module steam/water separator design without significantly increasing the pressure drop while simultaneously minimizing the vertical distance (spacing) between the primary and secondary separation stages. The development work included extensive air/water and steam/water testing. The steam/water tests were performed at a common pressure of 300 psia (2.1 MPa) with comparable water and steam flows

  11. Underground mining of the lower 163 zone through groundwater drainage at the Eagle Point Mine

    International Nuclear Information System (INIS)

    Robson, D.M.; Bashir, R.; Thomson, J.; Klemmer, S.; Rigden, A.

    2010-01-01

    The Eagle Point Mine is part of the Cameco Rabbit Lake Operation. The mine produces uranium ore using the long-hole, vertical and horizontal retreat mining method. The majority of the mine workings are under Wollaston Lake and cementitious grouting is used as one of the water control measures. Historical groundwater table in the mining area was close to ground surface. The Lower 163 Zone encompasses an estimated 4.2 million pounds U_3O_8 geological resource that was not considered feasible to mine due to the expected groundwater flows in the area. Cross-hole testing was conducted to better understand the groundwater flow through various geologic units. A local depressurization test was conducted to assess the potential for lowering the water table. Following testing an active depressurization was conducted to lower the groundwater table below the planned mining areas. This resulted in safe and drier mining conditions and allowed for the successful extraction of the ore body. (author)

  12. Elementary Statistics Tables

    CERN Document Server

    Neave, Henry R

    2012-01-01

    This book, designed for students taking a basic introductory course in statistical analysis, is far more than just a book of tables. Each table is accompanied by a careful but concise explanation and useful worked examples. Requiring little mathematical background, Elementary Statistics Tables is thus not just a reference book but a positive and user-friendly teaching and learning aid. The new edition contains a new and comprehensive "teach-yourself" section on a simple but powerful approach, now well-known in parts of industry but less so in academia, to analysing and interpreting process dat

  13. Validity and interobserver agreement of lower extremity local tissue water measurements in healthy women using tissue dielectric constant

    DEFF Research Database (Denmark)

    Jensen, Mads R; Birkballe, Susanne; Nørregaard, Susan

    2012-01-01

    Tissue dielectric constant (TDC) measurement may become an important tool in the clinical evaluation of chronic lower extremity swelling in women; however, several factors are known to influence TDC measurements, and comparative data on healthy lower extremities are few.......Tissue dielectric constant (TDC) measurement may become an important tool in the clinical evaluation of chronic lower extremity swelling in women; however, several factors are known to influence TDC measurements, and comparative data on healthy lower extremities are few....

  14. Utilizing NASA Earth Observations to Enhance Flood Impact Products and Mitigation in the Lower Mekong Water Basin

    Science.gov (United States)

    Doyle, C.; Gao, M.; Spruce, J.; Bolten, J. D.; Weber, S.

    2014-12-01

    This presentation discusses results of a project to develop a near real time flood monitoring capability for the Lower Mekong Water Basin (LMB), the largest river basin in Southeast Asia and home to more than sixty million people. The region has seen rapid population growth and socio-economic development, fueling unsustainable deforestation, agricultural expansion, and stream-flow regulation. The basin supports substantial rice farming and other agrarian activities, which heavily depend upon seasonal flooding. But, floods due to typhoons and other severe weather events can result in disasters that cost millions of dollars and cause hardships to millions of people. This study uses near real time and historical Aqua and Terra MODIS 250-m resolution Normalized Difference Vegetation Index (NDVI) products to map flood and drought impact within the LMB. In doing so, NDVI change products are derived by comparing from NDVI during the wet season to a baseline NDVI from the dry season. The method records flood events, which cause drastic decreases in NDVI compared to non-flooded conditions. NDVI change product computation was automated for updating a near real-time system, as part of the Committee on Earth Observing Satellites Disaster Risk Management Observation Strategy. The system is a web-based 'Flood Dashboard that will showcase MODIS flood monitoring products, along with other flood mapping and weather data products. This flood dashboard enables end-users to view and assess a variety of geospatial data to monitor floods and flood impacts in near real-time, as well provides a platform for further data aggregation for flood prediction modeling and post-event assessment.

  15. Water-quality assessment of the Lower Grand River Basin, Missouri and Iowa, USA, in support of integrated conservation practices

    Science.gov (United States)

    Wilkison, Donald H.; Armstrong, Daniel J.

    2016-01-01

    The effectiveness of agricultural conservation programmes to adequately reduce nutrient exports to receiving streams and to help limit downstream hypoxia issues remains a concern. Quantifying programme success can be difficult given that short-term basin changes may be masked by long-term water-quality shifts. We evaluated nutrient export at stream sites in the 44 months that followed a period of increased, integrated conservation implementation within the Lower Grand River Basin. These short-term responses were then compared with export that occurred in the main stem and adjacent rivers in northern Missouri over a 22-year period to better contextualize any recent changes. Results indicate that short-term (October 2010 through May 2014) total nitrogen (TN) concentrations in the Grand River were 20% less than the long-term average, and total phosphorus (TP) concentrations were 23% less. Nutrient reductions in the short term were primarily the result of the less-than-average precipitation and, consequently, streamflow that was 36% below normal. Therefore, nutrient concentrations measured in tributary streams were likely less than normal during the implementation period. Northern Missouri streamflow-normalized TN concentrations remained relatively flat or declined over the period 1991 through 2013 likely because available sources of nitrogen, determined as the sum of commercial fertilizers, available animal manures and atmospheric inputs, were typically less than crop requirement for much of that time frame. Conversely, flow-normalized stream TP concentrations increased over the past 22 years in northern Missouri streams, likely in response to many years of phosphorus inputs in excess of crop requirements. Stream nutrient changes were most pronounced during periods that coincided with the major tillage, planting and growth phases of row crops and increased streamflow. Nutrient reduction strategies targeted at the period February through June would likely have the

  16. Variations in selected water quality variables and metal concentrations in the sediment of the lower Olifants and Selati rivers, South Africa

    Directory of Open Access Journals (Sweden)

    T. Seymore

    1994-08-01

    Full Text Available A survey of the water and sediment quality of the lower Olifants River and lower Selati River was carried out. Metal concentrations (Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn in the water and sediment, as well as the physical and chemical characteristics of the water were determined over a two-year period (April 1990 - February 1992. The water quality of the lower Selati River, which flows through the Phalaborwa area, was found to be influenced by the mining and industrial activities in the area. It was also the case with the lower Olifants River after the Selati-Olifants confluence, although the concentrations of most variables did decrease from the western side of the Kruger National Park to the eastern side due to dilution of the water by tributaries of the Olifants River. Variables of special concern were sodium, fluoride. chloride, sulphate, potassium, the total dissolved salts and the metal concentrations (except strontium. The water quality of the Selati River in the study area is a great cause of concern and a further degradation thereof cannot be afforded.

  17. Empirical yield tables for Michigan.

    Science.gov (United States)

    Jerold T. Hahn; Joan M. Stelman

    1984-01-01

    Describes the tables derived from the 1980 Forest Survey of Michigan and presents ways the tables can be used. These tables are broken down according to Michigan's four Forest Survey Units, 14 forest types, and 5 site-index classes.

  18. Empirical yield tables for Wisconsin.

    Science.gov (United States)

    Jerold T. Hahn; Joan M. Stelman

    1989-01-01

    Describes the tables derived from the 1983 Forest Survey of Wisconsin and presents ways the tables can be used. These tables are broken down according to Wisconsin`s five Forest Survey Units and 14 forest types.

  19. Permit.LOA table

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This table includes the effective dates by vessel and permit number for each issued letter of authorization (LOA) by the Permit Office (APSD)

  20. VMS forms Output Tables

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These output tables contain parsed and format validated data from the various VMS forms that are sent from any given vessel, while at sea, from the VMS devices on...

  1. The Periodic Table CD.

    Science.gov (United States)

    Banks, Alton J.; Holmes, Jon L.

    1995-01-01

    Describes the characteristics of the digitized version of The Periodic Table Videodisc. Provides details about the organization of information and access to the data via Macintosh and Windows computers. (DDR)

  2. Setting the Periodic Table.

    Science.gov (United States)

    Saturnelli, Annette

    1985-01-01

    Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

  3. Body Mass Index Table

    Science.gov (United States)

    ... Families ( We Can! ) Health Professional Resources Body Mass Index Table 1 for BMI greater than 35, go ... Health Information Email Alerts Jobs and Careers Site Index About NHLBI National Institute of Health Department of ...

  4. Decision table languages and systems

    CERN Document Server

    Metzner, John R

    1977-01-01

    ACM Monograph Series: Decision Table Languages and Systems focuses on linguistic examination of decision tables and survey of the features of existing decision table languages and systems. The book first offers information on semiotics, programming language features, and generalization. Discussions focus on semantic broadening, outer language enrichments, generalization of syntax, limitations, implementation improvements, syntactic and semantic features, decision table syntax, semantics of decision table languages, and decision table programming languages. The text then elaborates on design im

  5. 27 CFR 30.66 - Table 6, showing respective volumes of alcohol and water and the specific gravity in both air and...

    Science.gov (United States)

    2010-04-01

    ... respective volumes of alcohol and water and the specific gravity in both air and vacuum of spirituous liquor... volumes of alcohol and water and the specific gravity in both air and vacuum of spirituous liquor. This... gallon of water in air by the specific gravity in air of the spirits—8.32823 by 0.88862—the product (7...

  6. Influence of water vapour on the height distribution of positive ions, effective recombination coefficient and ionisation balance in the quiet lower ionosphere

    Directory of Open Access Journals (Sweden)

    V. Barabash

    2014-03-01

    Full Text Available Mesospheric water vapour concentration effects on the ion composition and electron density in the lower ionosphere under quiet geophysical conditions were examined. Water vapour is an important compound in the mesosphere and the lower thermosphere that affects ion composition due to hydrogen radical production and consequently modifies the electron number density. Recent lower-ionosphere investigations have primarily concentrated on the geomagnetic disturbance periods. Meanwhile, studies on the electron density under quiet conditions are quite rare. The goal of this study is to contribute to a better understanding of the ionospheric parameter responses to water vapour variability in the quiet lower ionosphere. By applying a numerical D region ion chemistry model, we evaluated efficiencies for the channels forming hydrated cluster ions from the NO+ and O2+ primary ions (i.e. NO+.H2O and O2+.H2O, respectively, and the channel forming H+(H2On proton hydrates from water clusters at different altitudes using profiles with low and high water vapour concentrations. Profiles for positive ions, effective recombination coefficients and electrons were modelled for three particular cases using electron density measurements obtained during rocket campaigns. It was found that the water vapour concentration variations in the mesosphere affect the position of both the Cl2+ proton hydrate layer upper border, comprising the NO+(H2On and O2+(H2On hydrated cluster ions, and the Cl1+ hydrate cluster layer lower border, comprising the H+(H2On pure proton hydrates, as well as the numerical cluster densities. The water variations caused large changes in the effective recombination coefficient and electron density between altitudes of 75 and 87 km. However, the effective recombination coefficient, αeff, and electron number density did not respond even to large water vapour concentration variations occurring at other altitudes in the mesosphere. We determined the water

  7. Ground-survey and water-quality data for selected wetlands on or near the Lower Brule Indian Reservation in South Dakota, 2012-13

    Science.gov (United States)

    Neitzert, Kathleen M.; Thompson, Ryan F.

    2015-08-20

    Numerous lakes, ponds, and wetlands are located within the Lower Brule Indian Reservation. Wetlands are an important resource providing aquatic habitat for plants and animals, and acting as a natural water filtration system. Several of the wetlands on or near the reservation are of particular interest, but information on the physical and biological integrity of these wetlands was needed to provide a base-line reference when planning for future water management needs. A reconnaissance-level study of selected wetlands on and near the Lower Brule Indian Reservation was completed in 2012–13 by the U.S. Geological Survey in cooperation with the Lower Brule Sioux Tribe using ground surveys and water-quality analyses. Ground surveys of six wetland areas (Dorman Slough, Little Bend Wetlands, Miller Pond, Potter Slough, an unnamed slough, and West Brule Community wetlands) were completed to map land, water, vegetation, and man-made features of the selected wetland areas using real-time kinematic global navigation satellite systems equipment. Water samples were collected from four of the selected wetlands. Two separate waterbodies were sampled at one of the wetlands for a total of five sampling locations. Water samples were analyzed for physical properties, selected inorganics, metals, nutrients, and suspended sediment. Concentrations of calcium, sodium, and sulfate were greater at the two wetland sites fed by ground water, compared to the wetland sites fed by surface runoff.

  8. The 2005 CHF look-up table

    International Nuclear Information System (INIS)

    Groeneveld, D.C.; Vasic, A.Z.; Leung, L.K.H.; Durmayaz, A.; Shan, J.Q.; Yang, J.; Cheng, S.C.

    2005-01-01

    Full text of publication follows: CHF Look-up tables have been used widely for the prediction of the Critical Heat Flux (CHF) The CHF look-up table is basically a normalized data bank. The first CHF look-up table was constructed by Doroshchuk et al. (1975), using a limited database of 5 000 data points. This table, and all subsequent tables, contain normalized CHF values for a vertical 8 mm water-cooled tube for various pressures, mass fluxes and qualities. The CHF table development work has since been in progress at various institutions (e.g. CENG-Grenoble, University of Ottawa (UO), Ottawa, IPPE, Obninsk, and AECL, Chalk River) using an ever increasing data base. The 1995 CHF look-up table employs a data base containing about 30 000 CHF points and provides CHF values for an 8 mm ID, water-cooled tube, for 19 pressures, 20 mass fluxes, and 23 qualities. covering the full range of conditions of practical interest. The 2005 CHF LUT is an update to the 1995 LUT and addresses several concerns raised in the literature. The major improvements made are: - enhancement of the quality of the data base of the CHF look-up table (identify outliers, improve screening procedures); - increase in the data base by adding recently obtained data; - employment of greater subdivision of the look-up table by using smaller intervals in the independent parameters (pressure, mass flux and quality) at conditions where the variation in CHF is significant; - improvement of the smoothness of the CHF look-up table. This was done by the use of logarithmic functions for CHF, using optimum Spline functions etc. A discussion of the impact of these changes on the prediction accuracy and table smoothness is presented. It will be shown that the 2005 CHF look-up table is characterized by a significant improvement in accuracy and smoothness. [1] D. Groeneveld is the corresponding author. He is an Adjunct Professor at the University of Ottawa. (authors)

  9. Isotopic Investigation of the Origin of Ammonia and Nitrate in the Mineral Spring Waters of Scuol (Lower Engadine, South Eastern Switzerland)

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, J.; Leuenberger, F.; Balderer, W. [Eidgenoessische Technische Hochschule Zuerich, Geological Institute, Engineering Geology, Zuerich (Switzerland); Eichinger, L. [Hydroisotop GmbH, Schweitenkirchen (Germany)

    2013-07-15

    The mineral springs of scuol-Tarasp are located in the lower Engadine Valley, Graubuenden, south eastern Switzerland. In the last century, they have been investigated with respect to their basic chemical parameters. These springs yield a highly mineralized carbon dioxide water, with large quantities of free CO{sub 2}. Some of the springs also contain high amounts of ammonia. In order to better understand the origin of the water of the different springs, 13 were investigated, focusing this study on the ammonia content and the isotopic composition of the ammonia in the waters. It results from the study that 7 of the 13 springs contain ammonia. Based on the isotope and chemical results we suggest an origin of that ammonia by natural processes as water-rock interaction within the sedimentary and mantle rocks along the water flow path resulting in the enrichment of ammonia as seen in the investigated spring waters. (author)

  10. Selenium and hazardous elements distribution in plant-soil-water system and human health risk assessment of Lower Cambrian, Southern Shaanxi, China.

    Science.gov (United States)

    Du, Yajun; Luo, Kunli; Ni, Runxiang; Hussain, Rahib

    2018-03-01

    The natural selenium poisoning due to toxic Se levels in food chain had been observed in humans and animals in Lower Cambrian outcrop areas in Southern Shaanxi, China. To find out the distribution pattern of selenium and other hazardous elements in the plant, soil and water of Lower Cambrian in Southern Shaanxi, China, and their possible potential health risk, a total of 30 elements were analyzed and the health risk assessment of 18 elements was calculated. Results showed that the soil, plant and natural water of Lower Cambrian all had relatively high Se levels. In Lower Cambrian, the soil was enriched with Se, As, Ba, Cu, Mo, Ni, Zn, Ga, Cd and Cr (1.68 food intake was the major pathway. For minimizing potential health risk, the local inhabitants should use the mix-imported food with local growing foods.

  11. Biological and associated water-quality data for lower Olmos Creek and upper San Antonio River, San Antonio, Texas, March-October 1990

    Science.gov (United States)

    Taylor, R. Lynn

    1995-01-01

    Biological and associated water-quality data were collected from lower Olmos Creek and upper San Antonio River in San Antonio, Texas, during March-October 1990, the second year of a multiyear data-collection program. The data will be used to document water-quality conditions prior to implementation of a proposal to reuse treated wastewater to irrigate city properties in Olmos Basin and Brackenridge Parks and to augment flows in the Olmos Creek/San Antonio River system.

  12. Lower Colorado River GRP Drinking Water Protection Area Buffers for Non-Transient Wells, Nevada, 2012, Nevada Division of Environmental Protection Bureau of Water Pollution Control

    Data.gov (United States)

    U.S. Environmental Protection Agency — Public Water System wells are collected and maintained by NDEP Bureau of Safe Drinking Water (BSDW). Buffers include community wells and non-transient non-community...

  13. Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA

    Science.gov (United States)

    Crandall, C.A.; Katz, B.G.; Hirten, J.J.

    1999-01-01

    Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88 m above mean sea level in April 1996 and discharge peaked at 360 m3/s. During these high-flow conditions, water from the Suwannee River migrated directly into the karstic Upper Floridan aquifer, the main source of water supply for the area. Changes in the chemical composition of groundwater were quantified using naturally occurring geochemical tracers and mass-balance modeling techniques. Mixing of river water with groundwater was indicated by a decrease in the concentrations of calcium, silica, and 222Rn; and by an increase in dissolved organic carbon (DOC), tannic acid, and chloride, compared to low-flow conditions in water from a nearby monitoring well, Wingate Sink, and Little River Springs. The proportion (fraction) of river water in groundwater ranged from 0.13 to 0.65 at Wingate Sink and from 0.5 to 0.99 at well W-17258, based on binary mixing models using various tracers. The effectiveness of a natural tracer in quantifying mixing of river water and groundwater was related to differences in tracer concentration of the two end members and how conservatively the tracer reacted in the mixed water. Solutes with similar concentrations in the two end-member waters (Na, Mg, K, Cl, SO4, SiO2) were not as effective tracers for quantifying mixing of river water and groundwater as those with larger differences in end-member concentrations (Ca, tannic acid, DOC, 222Rn, HCO3). ?? Springer-Verlag.

  14. Reading the Water Table: The Interaction between Literacy Practices and Groundwater Management Training in Preparing Farmers for Climate Change in South India

    Science.gov (United States)

    Chavva, Konda Reddy; Smith, Cristine A.

    2012-01-01

    This article focuses on farmers' use of literacy for individual decision-making on crop-water management and crop choices and investigates how farmer participants perceive the usefulness of Farmer Water School (FWS) training. It draws upon a study conducted with farmers of Kurnool district of Andhra Pradesh, India. This study has demonstrated that…

  15. Empirical yield tables for Minnesota.

    Science.gov (United States)

    Jerold T. Hahn; Gerhard K. Raile

    1982-01-01

    Describes the tables derived from the 1977 Forest Survey of Minnesota and presents examples of how the tables can be used. These tables are broken down according to Minnesota's four Forest Survey Units, 14 forest types, and 5 site index classes. Presents 210 of the 350 possible tables that contained sufficient data to justify publication.

  16. X-ray table

    International Nuclear Information System (INIS)

    Craig, J.R.; Otto, G.W.

    1980-01-01

    An X-ray radiographic or fluoroscopic table is described which includes a film holder with a frame attached to a cable running over end pulleys for positioning the holder longitudinally as desired under the table top. The holder has a front opening to receive a cassette-supporting tray which can be slid out on tracks to change the cassette. A reed switch on the frame is opened by a permanent magnet on the tray only when the tray is half-way out. When the switch is closed, an electromagnet locks the pulley and the holder in place. The holder is thus automatically locked in place not only during exposure (tray in) but when the tray is out for changing the cassette. To re-position the holder, the operator pulls the tray half-out and, using the tray itself, pushes the holder along the table, the holder being counterbalanced by a weight. (author)

  17. Table Tennis Club

    CERN Multimedia

    Table Tennis Club

    2012-01-01

    The CERN Table Tennis club and the Meyrin CTT are organizing two Table Tennis workshops from 2 to 6 July and from 20 to 24 August 2012 inclusive in Meyrin. A professional would be with your children from 14.00 pm to 18.00 pm: an instructor J + S category A. Training courses with specific themes, individual courses would be given depending on the level of the child’s game, “discoveries –table tennis games” courses and games with the robot. Other activities (stretching, relaxation). Afternoons (from 18 to 20 children): 40 CHF per workshop and per child. Evenings (from 18 to 20 adults): 60 CHF per workshop and per adult. For further information, please contact Mr. Monteil : Mobile: (+33) 06 61 31 70 47 E-mail: wilfried.monteil@free.fr.

  18. Periodic table of elements

    International Nuclear Information System (INIS)

    Fluck, E.; Heumann, K.G.

    1985-01-01

    Following a recommendation by the International Union for Pure and Applied Chemistry (IUPAC), the groups of the periodic table shall be numbered from 1 to 18, instead of I to VIII as before. The recommendations has been approved of by the Committee on Nomenclature of the American Chemical Society. The new system abandons the distinction between main groups (a) and auxiliary groups (b), which in the past frequently has been the reason for misunderstandings between European and American chemists, due to different handling. The publishing house VCH Verlagsgesellschaft recently produced a new periodic table that shows the old and the new numbering system together at a glance, so that chemists will have time to get familiar with the new system. In addition the new periodic table represents an extensive data compilation arranged by elements. The front page lists the chemical properties of elements, the back page their physical properties. (orig./EF) [de

  19. Pros and Cons of Adopting Water-Wise Approaches in the Lower Reaches of the Amu Darya: A Socio-Economic View

    Directory of Open Access Journals (Sweden)

    Maksud Bekchanov

    2010-05-01

    Full Text Available The increased frequency of water shortages parallel to growing demands for agricultural commodities in the lower reaches of the Amu Darya River, Central Asia, calls for improving the system-level water use efficiency, by using interventions at the field level. Despite the existence of various best practices of effective water use (defined here as “water-wise options”, they are not widely adopted by farmers owing to high initial costs of investment and lack of the necessary knowledge and skills of a new generation of farmers after the Soviet era. For assessing the potential of several water-wise techniques, key indicators such as water use reduction rate (WURR, economic efficiency (EE, and financial viability (FV were combined with expert surveys. A SWOT procedure was used to analyze the (disadvantages, opportunities and constraints of adopting the selected water-wise methods. Results show that the examined options have substantial potential for increasing water use efficiency under promising EE. The various recommendations aim at improving the sustainability of irrigation water use.

  20. Dosimetric Effects Of Different Treatment Tables During Radiotherapy

    International Nuclear Information System (INIS)

    Murkovic, M.; Grego, T.; Bibic, J.

    2015-01-01

    The aim of our study was to measure the effect of mega-voltage photon beam attenuation when treating patients through carbon fibre treatment table with and without the carbon laminate base plate on it. We also examined the ability of XiO treatment planning system in modelling this effect. Direct attenuation measurements were made for two treatment tables, Siemens TxT 550 treatment table with TT-A table top and Elekta Precise table with iBEAM evo table top. On both treatment tables we used Orfit Base Plate (32301). Measurements were taken for two photon energies (6 MV and 18 MV), at two different field sizes (5 x 5 cm 2 and 10 x 10 cm 2 ) and different gantry angles in 50 intervals using stationary water phantom and Farmer type ionization chamber. These values were compared to values calculated in XiO. In order to account for the effect of table and base plate during treatment planning in XiO, customized table and base plate templates were develop in Focal planning system. To construct these customized templates, table and base plate contours as well as respective relative electron density's to water were obtained on CT scanner. The largest attenuation effect was seen for oblique treatment angles using low energy and small field sizes, 6.6 percent for the Elekta table top and 8.4 percent for Siemens table top. In this paper we show that customized table and base plate templates introduced in the patient treatment plan can accurately model the attenuation due to their presence to within 0.3 percent. Since dose modifications due to such carbon fiber accessories can be significant, it can be concluded that introduction of customized table and base plate templates into TPS brings an important improvement to patient treatment planning, and should be included in dose calculations whenever possible. (author).

  1. Lower-energy neutron sources for increasing the sensitivity of nuclear gages for measuring the water content of bulk materials

    International Nuclear Information System (INIS)

    Bailey, S.M.

    1977-01-01

    The sensitivity of a gage using a nuclear source for measuring the water content of bulk materials, such as plastic concrete, is increased by use of a lithium or fluorine neutron nuclear source. 3 figures

  2. Application of the new IAPWS Guideline on the fast and accurate calculation of steam and water properties with the Spline-Based Table Look-Up Method (SBTL) in RELAP-7

    Energy Technology Data Exchange (ETDEWEB)

    Kunick, Matthias; Kretzschmar, Hans-Joachim [Zittau/Goerlitz Univ. of Applied Sciences, Zittau (Germany). Dept. of Technical Thermodynamics; Berry, Ray A.; Martineau, Richard C. [Idaho National Laboratory, Idaho Falls, ID (United States). Nuclear Science and Technology; Gampe, Uwe [Dresden Univ. of Technology (Germany). Chair of Thermal Power Machinery and Plants

    2017-07-15

    The numerical simulation of thermalhydraulic processes in nuclear power plants requires very accurate and extremely fast algorithms for calculating the thermophysical properties of water and steam. In order to provide such algorithms, the International Association for the Properties of Water and Steam (IAPWS) has adopted the new ''IAPWS Guideline on the Fast Calculation of Steam and Water Properties with the Spline-Based Table Look-Up Method (SBTL)''. In this article, the SBTL method is applied to property functions of specific volume and specific internal energy (v,e) based on the scientific formulation IAPWS-95 and the latest IAPWS formulations for transport properties. From the newly generated SBTL functions, thermodynamic and transport properties as well as their derivatives and inverse functions are calculable in the fluid range of state for pressures up to 100 MPa and for temperatures up to 1273 K, including the metastable liquid and the metastable vapor regions. The SBTL functions reproduce the underlying formulations with an accuracy of 10-100 ppm and significantly reduced computing times. The SBTL method has been implemented into the nuclear reactor system safety analysis code RELAP-7 [2] to consider the real fluid behavior of water and steam in a novel 7-equation two-phase flow model.

  3. Code for the steam tables for pure water in visual basic 6.0.; Un codigo para las tablas de vapor para agua pura en visual basic 6.0

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Mahendra P. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2002-07-01

    The thermodynamic data of the water are of extreme importance in all of the branches of science and technology; the facilitate the understanding of the natural Earth processes. Nevertheless, for the electrical industry the water plays a very important role during the generation of electrical energy process. Different heat sources such as coal, oil, natural gas, nuclear fuel or the geothermal heat boil the water that forms the steam used to move the turbines. Consequently, the steam tables (the thermodynamic water data) are vital to model thermal and mass transference and physical-chemical processes during the generation of electrical energy. [Spanish] Los datos termodinamicos del agua son de suma importancia en todas las ramas de la ciencia y tecnologia, ellos facilitan el entendimiento de los procesos naturales de la Tierra. Sin embargo, para la industria electrica el agua juega un papel muy importante durante el proceso de generacion de energia electrica. Diferentes fuentes de calor tales como carbon, aceite, gas natural, combustible nuclear o el calor geotermico calientan el agua que forma el vapor utilizado para mover las turbinas. Luego entonces, las tablas de vapor (los datos termodinamicos de agua) son vitales para modelar transferencia termica y de masa y procesos fisico-quimico durante la generacion energia electrica.

  4. Changes in the water-table altitude of the unconfined aquifer, Wood River Valley aquifer system, south-central Idaho, October 2006 to October 2012.

    Data.gov (United States)

    Department of the Interior — Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established...

  5. Lower-limb hot-water immersion acutely induces beneficial hemodynamic and cardiovascular responses in peripheral arterial disease and healthy, elderly controls.

    Science.gov (United States)

    Thomas, Kate N; van Rij, André M; Lucas, Samuel J E; Cotter, James D

    2017-03-01

    Passive heat induces beneficial perfusion profiles, provides substantive cardiovascular strain, and reduces blood pressure, thereby holding potential for healthy and cardiovascular disease populations. The aim of this study was to assess acute responses to passive heat via lower-limb, hot-water immersion in patients with peripheral arterial disease (PAD) and healthy, elderly controls. Eleven patients with PAD (age 71 ± 6 yr, 7 male, 4 female) and 10 controls (age 72 ± 7 yr, 8 male, 2 female) underwent hot-water immersion (30-min waist-level immersion in 42.1 ± 0.6°C water). Before, during, and following immersion, brachial and popliteal artery diameter, blood flow, and shear stress were assessed using duplex ultrasound. Lower-limb perfusion was measured also using venous occlusion plethysmography and near-infrared spectroscopy. During immersion, shear rate increased ( P Lower-limb blood flow increased significantly in both groups, as measured from duplex ultrasound (>200%), plethysmography (>100%), and spectroscopy, while central and peripheral pulse-wave velocity decreased in both groups. Mean arterial blood pressure was reduced by 22 ± 9 mmHg (main effect P lower 3 h afterward. In PAD, popliteal shear profiles and claudication both compared favorably with those measured immediately following symptom-limited walking. A 30-min hot-water immersion is a practical means of delivering heat therapy to PAD patients and healthy, elderly individuals to induce appreciable systemic (chronotropic and blood pressure lowering) and hemodynamic (upper and lower-limb perfusion and shear rate increases) responses. Copyright © 2017 the American Physiological Society.

  6. Managing the impact of gold panning activities within the context of integrated water resources management planning in the Lower Manyame Sub-Catchment, Zambezi Basin, Zimbabwe

    Science.gov (United States)

    Zwane, Nonhlanhla; Love, David; Hoko, Zvikomborero; Shoko, Dennis

    Riverbed alluvial gold panning activities are a cause for degradation of river channels and banks as well as water resources, particularly through accelerated erosion and siltation, in many areas of Zimbabwe. The lower Manyame sub-catchment located in the Northern part of the country is one such area. This study analysed the implications of cross-sectoral coordination of the management of panning and its impacts. This is within the context of conflicts of interests and responsibilities. A situational analysis of different stakeholders from sectors that included mining, environment, water, local government and water users who were located next to identified panning sites, as well as panners was carried out. Selected sites along the Dande River were observed to assess the environmental effects. The study determined that all stakeholder groups perceived siltation and river bank degradation as the most severe effect of panning on water resources, yet there were divergent views with regards to coordination of panning management. The Water Act of 1998 does not give enough power to management institutions including the Lower Manyame Sub-catchment Council to protect water resources from the impacts of panning, despite the fact that the activities affect the water resource base. The Mines and Minerals Act of 1996 remains the most powerful legislation, while mining sector activities adversely affect environmental resources. Furthermore, complexities were caused by differences in the definition of water resources management boundaries as compared to the overall environmental resources management boundaries according to the Environmental Management Act (EMA) of 2000, and by separate yet parallel water and environmental planning processes. Environmental sector institutions according to the EMA are well linked to local government functions and resource management is administrative, enhancing efficient coordination.

  7. Data collection for cooperative water resources modeling in the Lower Rio Grande Basin, Fort Quitman to the Gulf of Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Passell, Howard David; Pallachula, Kiran (GRAM, Inc., Albuquerque, NM); Tidwell, Vincent Carroll; Villalobos, Joshua (Texas A& M University); Piccinni, Giovanni (Texas A& M University); Brainard, James Robert; Gerik, Thomas (Texas A& M University); Morrison, Wendy (Texas A& M University); Serrat-Capdevila, Aleix (University of Arizona); Valdes, Juan (University of Arizona); Sheng, Zhuping (Texas A& M University); Lovato, Rene (Instituto Mexicano de Tecnologia del Agua); Guitron, Alberto (Instituto Mexicano de Tecnologia del Agua); Ennis, Martha Lee; Aparicio, Javier (Instituto Mexicano de Tecnologia del Agua); Newman, Gretchen Carr (GRAM, Inc., Albuquerque, NM); Michelsen, Ari M. (Texas A& M University)

    2004-10-01

    Water resource scarcity around the world is driving the need for the development of simulation models that can assist in water resources management. Transboundary water resources are receiving special attention because of the potential for conflict over scarce shared water resources. The Rio Grande/Rio Bravo along the U.S./Mexican border is an example of a scarce, transboundary water resource over which conflict has already begun. The data collection and modeling effort described in this report aims at developing methods for international collaboration, data collection, data integration and modeling for simulating geographically large and diverse international watersheds, with a special focus on the Rio Grande/Rio Bravo. This report describes the basin, and the data collected. This data collection effort was spatially aggregated across five reaches consisting of Fort Quitman to Presidio, the Rio Conchos, Presidio to Amistad Dam, Amistad Dam to Falcon Dam, and Falcon Dam to the Gulf of Mexico. This report represents a nine-month effort made in FY04, during which time the model was not completed.

  8. Geology and ground-water resources of the lower Little Bighorn River Valley, Big Horn County, Montana, with special reference to the drainage of waterlogged lands, with a section on chemical quality of the water

    Science.gov (United States)

    Moulder, E.A.; Klug, M.F.; Morris, D.A.; Swenson, F.A.; Krieger, R.A.

    1960-01-01

    The lower Little Bighorn River valley, Montana, is in the unglaciated part of the Missouri Plateau section of the Great Plains physiographic province. The river and its principal tributaries rise in the Bighorn Mountains, and the confluence of this northward-flowing stream with the Bighorn River is near the east edge of Hardin, Mont. The normal annual precipitation ranges from about 12 inches in the northern part of the area to 15 inches in the southern part. The economy of the area is founded principally on farming, much of the low-lying land adjacent to the river being irrigated. The irrigated land is within the Crow Indian Reservation, although a part is privately owned. The bedrock formations exposed in the area are of Cretaceous age and include the Parkman sandstone, Claggett shale, Eagle sandstone, Telegraph Creek shale, and Cody shale. The Cloverly formation, Tensleep sandstone, and Madison limestone, which underlie but are not exposed in the area, and the Parkman sandstone in the southern half of the area appear to be the principal bedrock aquifers. All except the Parkman lie at depths ranging from a few feet to several thousand feet, and all appear to be capable of yielding water in commercial quantities. Some of the other formations arc capable of yielding enough water for domestic and stock needs. The river alluvium of Recent age and the Pleistocene terrace deposits are the principal unconsolidated formations in the area with respect to water supply and drainage. Wells yielding as much as 100 gallons per minute may be developed in favorable areas. Pumping tests reveal that the transmissibility of the coarser unconsolidated materials probably ranges from about 15,000 to 30,000 gallons per day per foot. Two tests of the Parkman sandstone showed transmissibilities of 6,000 and 20,000 gallons per day per foot. Although a test of the Cloverly formation showed a transmissibility of only 3,000 gallons per day per foot, the high artesian pressure--80 pounds per

  9. Climate change : transportation table

    International Nuclear Information System (INIS)

    Ogilvie, K.

    1999-01-01

    The Kyoto Protocol sets greenhouse gas (GHG) reduction targets for the post-2000 period. If ratified, Canada will be committed to reduce emissions of GHGs by 6 per cent below 1990 levels during the period 2008-2012. A recommended national strategy is to establish 'issue tables' that will advise the Ministers of Energy and Environment on preferred options to reach the Kyoto target and to identify early actions that can be taken. The 'Transportation Table' which is the focus of this paper, is one of the 15 sectoral tables. The Transportation Table will identify by July 1999, specific measures to mitigate GHG emissions from Canada's transportation sector. Currently, GHG emissions from the transportation sector are predicted to be 27 per cent above 1990 levels by 2010. Fuel taxes, emissions trading, and research into improved vehicle technologies and automotive fuels are some of the recommended options which can help reduce emissions trading from the transportation sector. Studies are underway to deal with emissions from transport in two sub-groups, freight and passenger. 1 fig

  10. Statistical tables 2003

    International Nuclear Information System (INIS)

    2003-01-01

    The energy statistical table is a selection of statistical data for energies and countries from 1997 to 2002. It concerns the petroleum, the natural gas, the coal, the electric power, the production, the external market, the consumption per sector, the energy accounting 2002 and graphs on the long-dated forecasting. (A.L.B.)

  11. A Modern Periodic Table.

    Science.gov (United States)

    Herrenden-Harker, B. D.

    1997-01-01

    Presents a modern Periodic Table based on the electron distribution in the outermost shell and the order of filling of the sublevels within the shells. Enables a student to read off directly the electronic configuration of the element and the order in which filling occurs. (JRH)

  12. Conversion tables. Appendix I

    International Nuclear Information System (INIS)

    McKerrell, H.

    1975-01-01

    Tables are presented for the conversion of standard (5568 year half-life) C-14 dates to calendar years. The major part of the data converts C-14 dates to tree-ring years: additional data are given, based on the Egyptian historical curve. (U.K.)

  13. Plant water use characteristics of five dominant shrub species of the Lower Rio Grande Valley, Texas, USA: implications for shrubland restoration and conservation.

    Science.gov (United States)

    Adhikari, Arjun; White, Joseph D

    2014-01-01

    The biogeographic distribution of plant species is inherently associated with the plasticity of physiological adaptations to environmental variation. For semi-arid shrublands with a legacy of saline soils, characterization of soil water-tolerant shrub species is necessary for habitat restoration given future projection of increased drought magnitude and persistence in these ecosystems. Five dominant native shrub species commonly found in the Lower Rio Grande Valley, TX, USA, were studied, namely Acacia farnesiana, Celtis ehrenbergiana, Forestiera angustifolia, Parkinsonia aculeata and Prosopis glandulosa. To simulate drought conditions, we suspended watering of healthy, greenhouse-grown plants for 4 weeks. Effects of soil salinity were also studied by dosing plants with 10% NaCl solution with suspended watering. For soil water deficit treatment, the soil water potential of P. glandulosa was the highest (-1.20 MPa), followed by A. farnesiana (-4.69 MPa), P. aculeata (-5.39 MPa), F. angustifolia (-6.20 MPa) and C. ehrenbergiana (-10.02 MPa). For the soil salinity treatment, P. glandulosa also had the highest soil water potential value (-1.60 MPa), followed by C. ehrenbergiana (-1.70 MPa), A. farnesiana (-1.84 MPa), P. aculeata (-2.04 MPa) and F. angustifolia (-6.99 MPa). Within the species, only C. ehrenbergiana and F. angustifolia for soil water deficit treatment and A. farnesiana for the salinity treatment had significantly lower soil water potential after 4 weeks of treatment (P < 0.05). We found that soil water potential, stomatal conductance and net photosynthesis of the species significantly reduced over time for both treatments (P < 0.05). We conclude that while all species exhibited capacities to withstand current water availability, some species demonstrated limited tolerance for extreme water stress that may be important for management of future shrub diversity in Lower Rio Grande Valley.

  14. Comparison of immittance spectroscopy analyses of ultra-pure and “pure” water in the lower frequency regime

    International Nuclear Information System (INIS)

    Macdonald, J. Ross

    2014-01-01

    Two different analyses of impedance data obtained from ultra-pure water allowed to equilibrate with the atmosphere have recently appeared. They both thus show much smaller low-frequency resistances than does ultra-pure water. Different fitting models were used in these analyses and led to appreciably different parameter estimates from their data fits. Their two “pure” water experimental data sets are here analyzed with a Poisson-Nernst-Planck model that incorporates the possibility of dissociation of a neutral species to positive and negative charges of arbitrary mobilities, anomalous diffusion in the interface region, and reaction of mobile ions at the electrodes. Complex-nonlinear-least-squares fitting of these data sets with either charges of a single sign mobile or with those of both signs mobile showed that the one-mobile choice was far superior to the two-mobile one. These results were compared both with newly calculated theoretical ultra-pure water immittance ones and with the results obtained in the earlier two papers, where different Poisson-Nernst-Planck-related fitting models were employed. Both involved the restrictive assumptions of full dissociation and two-mobile behavior with equal mobilities of the positive and negative charges. The dominant mobile charge species present in the equilibrated “pure” water data sets (protons for the ultra-pure water), involved mobile impurity ions, possibly oxygen ones. The Poisson-Nernst-Planck model used here is simpler than the other models, and it led to better fits of the data sets and to more physically significant parameter estimates than did the earlier fits

  15. Analyzing and Improving the Water-Table Fluctuation Method of Estimating Groundwater Recharge: Field Considerations Patros, T.B. and Parkin, G.W., School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada

    Science.gov (United States)

    Patros, T.; Parkin, G. W.

    2012-12-01

    The focus of the project is on measuring and quantifying groundwater recharge (GWR) using the water-table fluctuation (WTF) method. This method requires measuring the change in water-table (WT) height (Δh) during recharge (R) events and volumetric soil specific yield water content (θsy), (&/or) perhaps more correctly volumetric soil fillable water content (θf). The rise in WT can also result from other non-precipitation-related WTF causes (e.g., Lisse effect, temperature variations, barometric, lateral flow, Reverse Wieringermeer effect, encapsulated air, pumping), which must be counted for. The measurement of the storativity (S) terms (θsy) and/or θf) is, indeed, not clear-cut and often they are taken as being constant with depth, time, WT movement (Drying-Wetting & Freezing-Thawing) history and heterogeneity. In fact, these two terms (θsy & θf) are controversial in their definition, thus in their use, in the literature and may either overestimate the R, when using θsy, or underestimate it, when using θf. To resolve some of these questions, a novel-automated method is under development, at the University of Guelph's Elora Research Station (ERS) and Arboretum, along with a novel multi-event time series model. The long-term expected outcomes and significance of this study are; 1. Establishing accuracy in defining and evaluating the θsy and θf and using them accordingly in estimating GWR with the WTF method in order to overcome some of the existing substantial gaps in our knowledge of groundwater (GW) storage variation. 2. Obtaining GWR measurements at the local scale on a year-round basis, which are currently scarce or even completely lacking for many regions of Ontario and thus would provide a valuable database for guiding development of any policy requiring GWR. 3. Using this database to calibrate and test estimates of the spatial and temporal variability in regional-scale (watershed scale) GWR from approximate statistical techniques or deterministic

  16. Stable isotope and noble gas constraints on the source and residence time of spring water from the Table Mountain Group Aquifer, Paarl, South Africa and implications for large scale abstraction

    Science.gov (United States)

    Miller, J. A.; Dunford, A. J.; Swana, K. A.; Palcsu, L.; Butler, M.; Clarke, C. E.

    2017-08-01

    Large scale groundwater abstraction is increasingly being used to support large urban centres especially in areas of low rainfall but presents particular challenges in the management and sustainability of the groundwater system. The Table Mountain Group (TMG) Aquifer is one of the largest and most important aquifer systems in South Africa and is currently being considered as an alternative source of potable water for the City of Cape Town, a metropolis of over four million people. The TMG aquifer is a fractured rock aquifer hosted primarily in super mature sandstones, quartzites and quartz arenites. The groundwater naturally emanates from numerous springs throughout the cape region. One set of springs were examined to assess the source and residence time of the spring water. Oxygen and hydrogen isotopes indicate that the spring water has not been subject to evaporation and in combination with Na/Cl ratios implies that recharge to the spring systems is via coastal precipitation. Although rainfall in the Cape is usually modelled on orographic rainfall, δ18O and δ2H values of some rainfall samples are strongly positive indicating a stratiform component as well. Comparing the spring water δ18O and δ2H values with that of local rainfall, indicates that the springs are likely derived from continuous bulk recharge over the immediate hinterland to the springs and not through large and/or heavy downpours. Noble gas concentrations, combined with tritium and radiocarbon activities indicate that the residence time of the TMG groundwater in this area is decadal in age with a probable maximum upper limit of ∼40 years. This residence time is probably a reflection of the slow flow rate through the fractured rock aquifer and hence indicates that the interconnectedness of the fractures is the most important factor controlling groundwater flow. The short residence time of the groundwater suggest that recharge to the springs and the Table Mountain Group Aquifer as a whole is

  17. The brackish-water bivalve Waagenoperna from the Lower Jurassic Badaowan Formation of the Junggar Basin and its palaeoenvironmental and palaeogeographic significance

    Directory of Open Access Journals (Sweden)

    Yanhong Pan

    2013-01-01

    Full Text Available The brackish-water bivalve Waagenoperna Tokuyama, 1959 is reported from the Lower Jurassic Badaowan Formation at four localities, along the southern margin and western margin of the Junggar Basin. Taphonomic features recorded in the field indicate that it occurs in autochthonous or parautochthonous assemblages. The autecology of Waagenoperna therefore yields information on the palaeoenvironment of the area. The restriction of Waagenoperna to marine and brackish-water settings suggests that the sea water once reached these areas during the Sinemurian. This paper discusses the palaeogeographic implications and suggests an ingression of the sea water from the west to the western and southern part of the Junggar Basin. Additionally, the two Waagenoperna species collected from the Haojiagou section in the Junggar Basin are taxonomically documented.

  18. Isotopic Investigation of the Origin of Nitrate of Waters Outflowing from a Waste Deposit Site Near Scuol (Lower Engadine, South Eastern Switzerland)

    Energy Technology Data Exchange (ETDEWEB)

    Gschwend, M.; Leuenberger, F.; Eichinger, L. [Eidgenoessische Technische Hochschule Zuerich, Geological Institute, Engineering Geology, Zuerich (Switzerland); Balderer, W. [Hydroisotop GmbH, Schweitenkirchen, Germany (Germany)

    2013-07-15

    Near the village of Scuol in the Lower Engadine Valley (South Eastern Switzerland) Sot Ruinas, a waste disposal site for domestic and construction refuse, has been in use since the 1960s. It is situated in the vicinity of the Inn River. Over the last years enhanced concentrations of ammonia were found in the outflow of this waste site. But the observed elevated ammonia concentrations could also be a result of natural origin, by inflows of mineral water as observed in the mineral springs of the area. These springs could have acquired their high ammonia content by water-rock interaction with adjacent ultramafic rocks. The isotope analyses were oriented towards the hydrogen, nitrogen and oxygen isotopes on the ammonia, nitrate and nitrogen molecules. The effect of the waste on the outflowing water downstream could be proved by isotope ratios based on chemical processes of the nitrogen cycle and an influence of natural spring water was excluded. (author)

  19. The Lower Sevier River Basin Crop Monitor and Forecast Decision Support System: Exploiting Landsat Imagery to Provide Continuous Information to Farmers and Water Managers

    Science.gov (United States)

    Torres-Rua, A. F.; Walker, W. R.; McKee, M.

    2013-12-01

    The last century has seen a large number of innovations in agriculture such as better policies for water control and management, upgraded water conveyance, irrigation, distribution, and monitoring systems, and better weather forecasting products. In spite of this, irrigation management and irrigation water deliveries by farmers/water managers is still based on factors like water share amounts, tradition, and past experience on irrigation. These factors are not necessarily related to the actual crop water use; they are followed because of the absence of related information provided in a timely manner at an affordable cost. Thus, it is necessary to develop means to deliver continuous and personalized information about crop water requirements to water users/managers at the field and irrigation system levels so managers at these levels can better quantify the required versus available water for irrigation during the irrigation season. This study presents a new decision support system (DSS) platform that addresses the absence of information on actual crop water requirements and crop performance by providing continuous updated farm-based crop water use along with other farm performance indicators such as crop yield and farm management to irrigators and water managers. This DSS exploits the periodicity of the Landsat Satellite Mission (8 to 16 days, depending on the period of interest) to provide remote monitoring at the individual field and irrigation system levels. The Landsat satellite images are converted into information about crop water use, yield performance and field management through application of state-of-the-art semi-physical and statistical algorithms that provide this information at a pixel basis that are ultimately aggregated to field and irrigation system levels. A version of the DSS has been implemented for the agricultural lands in the Lower Sevier River, Utah, and has been operational since the beginning of the 2013 irrigation season. The main goal of

  20. Chemical Characterization of “Alcaparras” Stoned Table Olives from Northeast Portugal

    Directory of Open Access Journals (Sweden)

    Ricardo Malheiro

    2011-10-01

    Full Text Available Commercial stoned table olives named “alcaparras” from Trás-os-Montes (Portugal were chemically characterized. During three consecutive years (2004–2006 30 samples (10 per year were examined for their nutritional value (moisture, crude protein, total fat, ash, carbohydrates, and energy, with a detailed report of the fatty acids and tocopherols composition. Water was the major constituent (72.5 ± 5.5%, followed by fat (14.6 ± 5.1%. The average amount of protein and ash were 1.1% and 3.4%, respectively, reporting unusual ash values for table olives, related to the technological process. One hundred grams of fresh stoned table olives presented an average energetic value of 156 kcal, lower than most table olives. The lipids are rich in oleic acid (average of 77.7 ± 2.0%, followed by palmitic acid and linoleic acid. Samples showed an average of total tocopherols of 1.2 mg/100 g of fresh weight, being α-tocopherol the most abundant. Table olives are important sources of MUFA, as olive oil, recognized as a preventive factor in diseases in which free radicals are implicated, complemented by the amounts of vitamin E, with both antioxidant and vitamin action.

  1. Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection.

    Science.gov (United States)

    Zoll, Joffrey; Bouitbir, Jamal; Sirvent, Pascal; Klein, Alexis; Charton, Antoine; Jimenez, Liliana; Péronnet, François R; Geny, Bernard; Richard, Ruddy

    2015-01-01

    It has been suggested that oxygen (O2) diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates), which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients. Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1) at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg), with glutamate-malate or N, N, N', N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD)-ascorbate (with antimycin A) as substrates; and 2) at increasing adenosine diphosphate (ADP) concentration with glutamate-malate as substrate. As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate-malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD-ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was significantly lower with both electron donors in water enriched in O2 by electrolysis. This was not associated with any increase in the sensitivity of mitochondria to ADP; no significant difference was observed for the Km ADP between the two waters. In this experiment, a higher affinity of the mitochondria for O2 was observed in water enriched in O2 by electrolysis than by injection. This observation is consistent with the hypothesis that O2 diffusion can be facilitated in water enriched in O2 by the electrolytic process.

  2. Water Quality Management Studies, Middle Black Warrior and Lower Tombigbee Rivers, Warrior and Demopolis Lakes, July 1978-October 1979.

    Science.gov (United States)

    1983-04-01

    Environmental Samples, ~ Health Effects Research Laboratory, U. S. Environmental Protection Agency, Research Triangle Park, North Carolina, December, 1976. 7...Family Sapindaceae Genus cardiosperrum halicacabwn Family Malvaceae Genus Hibiscus moecheutos 0 H. militaris Family Hypericaceae Genus Hypericwn waiteri...Algal metabolites 4 can produce taste, coloration and even health problems whicn might limit water use. Orthophosphates and inorganic nitrogen (TIN) are

  3. Net Zero Fort Carson: Integrating Energy, Water, and Waste Strategies to Lower the Environmental Impact of a Military Base

    Science.gov (United States)

    Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net z...

  4. Community structure of age-0 fishes in paired mainstem and created shallow-water habitats in the Lower Missouri River

    Science.gov (United States)

    Starks, Trevor A.; Long, James M.; Dzialowski, Andrew R.

    2016-01-01

    Anthropogenic alterations to aquatic ecosystems have greatly reduced and homogenized riverine habitat, especially those used by larval and juvenile fishes. Creation of shallow-water habitats is used as a restoration technique in response to altered conditions in several studies globally, but only recently in the USA. In the summer of 2012, the U.S. Army Corps of Engineers sampled larval and juvenile fishes at six paired sites (mainstem and constructed chute shallow-water habitats) along a section of the Missouri River between Rulo, NE and St. Louis, MO, USA. From those samples, we enumerated and identified a total of 7622 fishes representing 12 families. Community responses of fishes to created shallow-water habitats were assessed by comparisons of species richness and diversity measures between paired sites and among sampling events. Shannon entropy measures were transformed, and gamma diversity (total diversity) was partitioned into two components, alpha (within community) and beta (between community) diversity using a multiplicative decomposition method. Mantel test results suggest site location, time of sampling event and habitat type were drivers of larval and juvenile community structure. Paired t-test results indicated little to no differences in beta diversity between habitat types; however, chute habitats had significantly higher alpha and gamma diversity as well as increased abundances of Asian carp larvae when compared with mainstem shallow-water habitat. Our results not only show the importance of created shallow-water habitat in promoting stream fish diversity but also highlight the role space and time may play in future restoration and management efforts. 

  5. Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones

    Energy Technology Data Exchange (ETDEWEB)

    Jay, David A.; Borde, Amy B.; Diefenderfer, Heida L.

    2016-04-26

    Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland hydrologic regimes at different locations on the river floodplain. A new predictive tool is introduced and validated, the potential SEV (pSEV), which can reduce the need for extensive new data collection in wetland restoration planning. Models of water levels and inundation frequency distinguish four zones encompassing eight reaches. The system zones are the wave- and current-dominated Entrance to river kilometer (rkm) 5; the Estuary (rkm-5 to 87), comprised of a lower reach with salinity, the energy minimum (where the turbidity maximum normally occurs), and an upper estuary reach without salinity; the Tidal River (rkm-87 to 229), with lower, middle, and upper reaches in which river flow becomes increasingly dominant over tides in determining water levels; and the steep and weakly tidal Cascade (rkm-229 to 234) immediately downstream from Bonneville Dam. The same zonation is seen in the water levels of floodplain stations, with considerable modification of tidal properties. The system zones and reaches defined here reflect geological features and their boundaries are congruent with five wetland vegetation zones

  6. Infiltration of pesticides in surface water into nearby drinking water supply wells

    DEFF Research Database (Denmark)

    Malaguerra, Flavio; Albrechtsen, Hans-Jørgen; Binning, Philip John

    Drinking water wells are often placed near streams because streams often overly permeable sediments and the water table is near the surface in valleys, and so pumping costs are reduced. The lowering of the water table by pumping wells can reverse the natural flow from the groundwater to the stream......, inducing infiltration of surface water to groundwater and consequently to the drinking water well. Many attenuation processes can take place in the riparian zone, mainly due to mixing, biodegradation and sorption. However, if the water travel time from the surface water to the pumping well is too short......, or if the compounds are poorly degradable, contaminants can reach the drinking water well at high concentrations, jeopardizing drinking water quality. Here we developed a reactive transport model to evaluate the risk of contamination of drinking water wells by surface water pollution. The model was validated using...

  7. Mathematics of Periodic Tables for Benzenoid Hydrocarbons.

    Science.gov (United States)

    Dias, Jerry Ray

    2007-01-01

    The upper and lower bounds for invariants of polyhex systems based on the Harary and Harborth inequalities are studied. It is shown that these invariants are uniquely correlated by the Periodic Table for Benzenoid Hydrocarbons. A modified periodic table for total resonant sextet (TRS) benzenoids based on the invariants of Ds and r(empty) is presented; Ds is the number of disconnections among the empty rings for fused TRS benzenoid hydrocarbons. This work represents a contribution toward deciphering the topological information content of benzenoid formulas.

  8. Contamination of rice (Oryza sativa L) with Cadmium and Arsenic by irrigation with the Bogota River water in rice soils of the Lower Basin

    International Nuclear Information System (INIS)

    Montenegro, Omar; Mejia L

    2001-01-01

    In this study, field and greenhouse experiments were simultaneously carried out with rice (oryza sativa l., variedad oryzica-1) in soils of the Bogota River lower basin (Los Manueles Series, a member of the clayed, mixed, isohipertermic family of the Fluventic Vertic Haplustepts) to evaluate the effect of Cd and As content of the irrigation waters (of the Bogota River and greenhouse) on soils and: 1) rice growth physiological parameters; 2) Cd and As accumulated in different parts of rice plants; 3) yields and other aspects and properties of rice crop. The results lead to the following conclusions: 1) The Cd and As content of the Bogota River water, increased during the driest months and was minimum in those with the highest precipitation; Cd and As concentrations in both seasons surpassed the maximum permissible limits. 2) Rice height was highest when irrigation water does have neither Cd nor As. Effects of both elements showed an inverse lineal tendency. 3) The gradual increase of Cd in irrigation water reduced in 12.5% the number of grains per panicle; the increase of As induced a 10% reduction. 4) The highest concentration of Cd and As in irrigation waters significantly reduced yields; maximum yields l were obtained when Cd and As were absent from irrigation waters. 5) For any concentration of As in irrigation water the highest concentration of Cd was accumulated in rice leafs when concentration of Cd 2 was 2mg/l; above this value Cd accumulation in leafs el decreased with the gradual increase of As concentration. 6) Cd and As accumulated in rice grains increased with the gradual increment of both elements in the irrigation waters; Cd and As accumulated were respectively 50 and 15 times higher than the maximum critical levels proposed for rice grains. 7) Cd and As accumulated progressively on soils with gradual increase of both elements in irrigation waters 8) Cd and As concentration in irrigation waters apparently does not affect the rice mill behavior

  9. A table-top LHC

    CERN Multimedia

    Barbara Warmbein

    2011-01-01

    Many years ago, when ATLAS was no more than a huge empty underground cavern and Russian artillery shell casings were being melted down to become part of the CMS calorimetry system, science photographer Peter Ginter started documenting the LHC’s progress. He was there when special convoys of equipment crossed the Jura at night, when cranes were lowering down detector slices and magnet coils were being wound in workshops. Some 18 years of LHC history have been documented by Ginter, and the result has just come out as a massive coffee table book full of double-page spreads of Ginter’s impressive images.   The new coffee table book, LHC: the Large Hadron Collider. Published by the Austrian publisher Edition Lammerhuber in cooperation with CERN and UNESCO Publishing, LHC: the Large Hadron Collider is an unusual piece in the company’s portfolio. As the publisher’s first science book, LHC: the Large Hadron Collider weighs close to five kilos and comes in a s...

  10. Substantive hemodynamic and thermal strain upon completing lower-limb hot-water immersion; comparisons with treadmill running

    OpenAIRE

    Thomas, Kate N.; van Rij, Andr? M.; Lucas, Samuel J.E.; Gray, Andrew R.; Cotter, James D.

    2016-01-01

    ABSTRACT Exercise induces arterial flow patterns that promote functional and structural adaptations, improving functional capacity and reducing cardiovascular risk. While heat is produced by exercise, local and whole-body passive heating have recently been shown to generate favorable flow profiles and associated vascular adaptations in the upper limb. Flow responses to acute heating in the lower limbs have not yet been assessed, or directly compared to exercise, and other cardiovascular effec...

  11. Estimates of Shear Stress and Measurements of Water Levels in the Lower Fox River near Green Bay, Wisconsin

    Science.gov (United States)

    Westenbroek, Stephen M.

    2006-01-01

    Turbulent shear stress in the boundary layer of a natural river system largely controls the deposition and resuspension of sediment, as well as the longevity and effectiveness of granular-material caps used to cover and isolate contaminated sediments. This report documents measurements and calculations made in order to estimate shear stress and shear velocity on the Lower Fox River, Wisconsin. Velocity profiles were generated using an acoustic Doppler current profiler (ADCP) mounted on a moored vessel. This method of data collection yielded 158 velocity profiles on the Lower Fox River between June 2003 and November 2004. Of these profiles, 109 were classified as valid and were used to estimate the bottom shear stress and velocity using log-profile and turbulent kinetic energy methods. Estimated shear stress ranged from 0.09 to 10.8 dynes per centimeter squared. Estimated coefficients of friction ranged from 0.001 to 0.025. This report describes both the field and data-analysis methods used to estimate shear-stress parameters for the Lower Fox River. Summaries of the estimated values for bottom shear stress, shear velocity, and coefficient of friction are presented. Confidence intervals about the shear-stress estimates are provided.

  12. Satial and seasonal variations o heavy metals in water and sediment samles collected rom the Lower Danube River

    OpenAIRE

    IONESCU Petra; RADU Violeta Monica; DEAK Gyorgy

    2016-01-01

    Surface water pollution with heavy metals represents one of the most relevant environmental issues, with severe outcomes on every other environmental compartment, affecting therefore the human health because of their toxicity, persistence and bioaccumulation tendency. The Danube, one of the most important rivers of Europe considering its course, crossing the continent from west to east, represents the main collector of all pollutants emitted by the ten countries it passes through, prior to di...

  13. Energy and water balance of two contrasting loblolly pine plantations on the lower coastal plain of North Carolina, USA

    Science.gov (United States)

    G. Sun; A. Noormets; M.J. Gavazzi; S.G. McNulty; J. Chen; J.-C. King Domec; D.M. Amatya; R.W. Skaggs

    2010-01-01

    During 2005–2007, we used the eddy covariance and associated hydrometric methods to construct energy and water budgets along a chronosequence of loblolly pine (Pinus taeda) plantations that included a mid-rotation stand (LP) (i.e., 13–15 years old) and a recently established stand on a clearcut site (CC) (i.e., 4–6 years old) in Eastern...

  14. Modeling the potential impacts of climate change on the water table level of selected forested wetlands in the southeastern United States

    OpenAIRE

    Zhu, Jie; Sun, Ge; Li, Wenhong; Zhang, Yu; Miao, Guofang; Noormets, Asko; McNulty, Steve G.; King, John S.; Kumar, Mukesh; Wang, Xuan

    2017-01-01

    The southeastern United States hosts extensive forested wetlands, providing ecosystem services including carbon sequestration, water quality improvement, groundwater recharge, and wildlife habitat. However, these wetland ecosystems are dependent on local climate and hydrology, and are therefore at risk due to climate and land use change. This study develops site-specific empirical hydrologic models for five forested wetlands with different characteristics by analyzing long-t...

  15. Tomographic examination table

    International Nuclear Information System (INIS)

    Redington, R.W.; Henkes, J.L.

    1979-01-01

    Equipment is described for positioning and supporting patients during tomographic mammography using X-rays. The equipment consists of a table and fabric slings which permit the examination of a downward, pendant breast of a prone patient by allowing the breast to pass through a aperture in the table into a fluid filled container. The fluid has an X-ray absorption coefficient similar to that of soft human tissue allowing high density resolution radiography and permitting accurate detection of breast tumours. The shape of the equipment and the positioning of the patient allow the detector and X-ray source to rotate 360 0 about a vertical axis through the breast. This permits the use of relatively simple image reconstruction algorithms and a divergent X-ray geometry. (UK)

  16. Seasonal to Decadal Variations of Water Vapor in the Tropical Lower Stratosphere Observed with Balloon-Borne Cryogenic Frost Point Hygrometers

    Science.gov (United States)

    Fujiwara, M.; Voemel, H.; Hasebe, F.; Shiotani, M.; Ogino, S.-Y.; Iwasaki, S.; Nishi, N.; Shibata, T.; Shimizu, K.; Nishimoto, E.; hide

    2010-01-01

    We investigated water vapor variations in the tropical lower stratosphere on seasonal, quasi-biennial oscillation (QBO), and decadal time scales using balloon-borne cryogenic frost point hygrometer data taken between 1993 and 2009 during various campaigns including the Central Equatorial Pacific Experiment (March 1993), campaigns once or twice annually during the Soundings of Ozone and Water in the Equatorial Region (SOWER) project in the eastern Pacific (1998-2003) and in the western Pacific and Southeast Asia (2001-2009), and the Ticosonde campaigns and regular sounding at Costa Rica (2005-2009). Quasi-regular sounding data taken at Costa Rica clearly show the tape recorder signal. The observed ascent rates agree well with the ones from the Halogen Occultation Experiment (HALOE) satellite sensor. Average profiles from the recent five SOWER campaigns in the equatorial western, Pacific in northern winter and from the three Ticosonde campaigns at Costa Rica (10degN) in northern summer clearly show two effects of the QBO. One is the vertical displacement of water vapor profiles associated with the QBO meridional circulation anomalies, and the other is the concentration variations associated with the QBO tropopause temperature variations. Time series of cryogenic frost point hygrometer data averaged in a lower stratospheric layer together with HALOE and Aura Microwave Limb Sounder data show the existence of decadal variations: The mixing ratios were higher and increasing in the 1990s, lower in the early 2000s, and probably slightly higher again or recovering after 2004. Thus linear trend analysis is not appropriate to investigate the behavior of the tropical lower stratospheric water vapor.

  17. 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...

  18. Seashore marine table quiz

    OpenAIRE

    Institute, Marine

    2013-01-01

    Develop an increasing awareness of plants and animals that live in local marine environments including the seashore, seas and oceans of Ireland. After learning all about the seashore and other marine related lessons, this quiz can be used to evaluate the student’s knowledge of the marine related living things and natural environments. The table quiz can be used as a guide, highlighting facts about the marine environment and some of the animals that live there.

  19. Table Tennis Club

    CERN Document Server

    Table Tennis Club

    2012-01-01

    2012 CERN Table Tennis Tournament As the campaign launched by the CERN medical service “Move! & Eat better” is designed in particular to encourage people at CERN to take more regular exercise, the CERN Table Tennis Club, with its traditional CERN Table Tennis Tournament is providing an excellent opportunity to practice moving. The tournament will take place at the Meyrin CTT, 2 rue de Livron, Saturday August 25, 2012, in the afternoon (starting at 13:30). It is open to all CERN staff, users, visitors and families, including of course summer students, who are strongly encouraged to participate. In order to register, simply send an E-mail to Jean-Pierre Revol (jean-pierre.revol@cern.ch). You may also find useful information on the Club Web page http://www.cern.ch/tabletennis CERN 2011 champion Savitha Flaecher, between the finalist Bertrand Mouches on her left, the winner of the consolation draw on her right (Sudarshan Paramesvaran), and far left, Denis Moriaud (semi-finalist a...

  20. SRTC - Gap Analysis Table

    International Nuclear Information System (INIS)

    M.L. Johnson

    2005-01-01

    The purpose of this document is to review the existing SRTC design against the ''Nuclear Safety Design Bases for License Application'' (NSDB) [Ref. 10] requirements and to identify codes and standards and supplemental requirements to meet these requirements. If these codes and standards and supplemental requirements can not fully meet these safety requirements then a ''gap'' is identified. These gaps will be identified here and addressed using the ''Site Rail Transfer Cart (SRTC) Design Development Plan'' [Ref. 14]. The codes and standards, supplemental requirements, and design development requirements are provided in the SRTC and associated rails gap analysis table in Appendix A. Because SRTCs are credited with performing functions important to safety (ITS) in the NSDB [Ref. 10], design basis requirements are applicable to ensure equipment is available and performs required safety functions when needed. The gap analysis table is used to identify design objectives and provide a means to satisfy safety requirements. To ensure that the SRTC and rail design perform required safety Functions and meet performance criteria, this portion of the gap analysis table supplies codes and standards sections and the supplemental requirements and identifies design development requirements, if needed

  1. Global Reference Tables Services Architecture

    Data.gov (United States)

    Social Security Administration — This database stores the reference and transactional data used to provide a data-driven service access method to certain Global Reference Table (GRT) service tables.

  2. Aggregation Algorithms in Heterogeneous Tables

    Directory of Open Access Journals (Sweden)

    Titus Felix FURTUNA

    2006-01-01

    Full Text Available The heterogeneous tables are most used in the problem of aggregation. A solution for this problem is to standardize these tables of figures. In this paper, we proposed some methods of aggregation based on the hierarchical algorithms.

  3. Electrical conductivity of the plagioclase-NaCl-water system and its implication for the high conductivity anomalies in the mid-lower crust of Tibet Plateau

    Science.gov (United States)

    Li, Ping; Guo, Xinzhuan; Chen, Sibo; Wang, Chao; Yang, Junlong; Zhou, Xingfan

    2018-02-01

    In order to investigate the origin of the high conductivity anomalies geophysically observed in the mid-lower crust of Tibet Plateau, the electrical conductivity of plagioclase-NaCl-water system was measured at 1.2 GPa and 400-900 K. The relationship between electrical conductivity and temperature follows the Arrhenius law. The bulk conductivity increases with the fluid fraction and salinity, but is almost independent of temperature (activation enthalpy less than 0.1 eV). The conductivity of plagioclase-NaCl-water system is much lower than that of albite-NaCl-water system with similar fluid fraction and salinity, indicating a strong effect of the major mineral phase on the bulk conductivity of the brine-bearing system. The high conductivity anomalies of 10-1 and 100 S/m observed in the mid-lower crust of Tibet Plateau can be explained by the aqueous fluid with a volume fraction of 1 and 9%, respectively, if the fluid salinity is 25%. The anomaly value of 10-1 S/m can be explained by the aqueous fluid with a volume fraction of 6% if the salinity is 10%. In case of Southern Tibet where the heat flow is high, the model of a thin layer of brine-bearing aqueous fluid with a high salinity overlying a thick layer of partial melt is most likely to prevail.

  4. A study for a guide chart of lower and upper boundary regions to avoid the condensation-induced water hammer in a long horizontal pipe

    International Nuclear Information System (INIS)

    Lee, Byung Jin

    1995-02-01

    Effects of the key system parameters such as the pipe length, the pipe diameter, the feedwater temperature and the system pressure on the critical flow rates of both the upper and the lower boundaries have been examined for long horizontal pipes. The upper and lower critical flow rates are sensitive to the pipe diameter, the pipe length and the system pressure, but not to the feedwater temperature over the practical operating ranges. Guide charts of the CIWH region boundary have been developed to be used in the system design and operation to predict the operating conditions vulnerable to the CIWH. The charts illustrate a series of the operating ranges bounded by the lower and the upper limiting curves where the water hammer is very likely to occur. A design and operational procedure has also been provided to help the designer and the operator to avoid the CIWH

  5. Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment Budget Along the Dam-Regulated Lower Roanoke River, North Carolina

    Science.gov (United States)

    Schenk, Edward R.; Hupp, Cliff R.; Richter, Jean M.; Kroes, Daniel E.

    2010-01-01

    Dam construction and its impact on downstream fluvial processes may substantially alter ambient bank stability, floodplain inundation patterns, and channel morphology. Most of the world's largest rivers have been dammed, which has prompted management efforts to mitigate dam effects. Three high dams (completed between 1953 and 1963) occur along the Piedmont portion of the Roanoke River, North Carolina; just downstream, the lower part of the river flows across largely unconsolidated Coastal Plain deposits. To document bank erosion rates along the lower Roanoke River, more than 700 bank erosion pins were installed along 124 bank transects. Additionally, discrete measurements of channel bathymetry, water clarity, and presence or absence of mass wasting were documented along the entire 153-kilometer-long study reach. Amounts of bank erosion in combination with prior estimates of floodplain deposition were used to develop a bank erosion and floodplain deposition sediment budget for the lower river. Present bank erosion rates are relatively high [mean 42 milimeters per year (mm/yr)] and are greatest along the middle reaches (mean 60 mm/yr) and on lower parts of the bank on all reaches. Erosion rates were likely higher along upstream reaches than present erosion rates such that erosion rate maxima have migrated downstream. Mass wasting and water clarity also peak along the middle reaches.

  6. TABLE OF CONTENTS TABLE OF CONTENTS

    African Journals Online (AJOL)

    eobe

    Effects of Variability in the Pozzolanic Properties of Rice Husk. Ash on the ... on Semi-Infinite Elastic Soils using Fourier Transform Method. H. N. Onah, N. N. ... Al – Si – Mg Alloy in Simulated Sea Water Environment. S. M. Adams, S. A. Yaro,.

  7. Uranium in mining water of kaolin open pit in Zarów (Lower Silesia); methodology of determination and genetic remarks.

    Science.gov (United States)

    Chau, N D; Wyszomirski, P; Chruściel, E; Ochoński, A

    1999-11-01

    In this paper, a method of determination of uranium 238 and 234 in mining waters of Andrzej kaolin open pit in Zarów (Lower Silesia) is presented. The method is based on independent measurements of alpha and beta radiation intensities by means of a liquid scintillation spectrometer alpha/beta. The initial volume of water sample was 3 dm3, then it was diminished by chemical preparation to 6 cm3, and then 12 cm3 of scintillator was added. The lower limit of detection (for the measurement time of 8 h) for both 234U and 238U amounted to 0.02 Bq/dm3. For determination of the uranium content in ferruginous sediments precipitating from mining waters of the above-mentioned open pit, gamma ray spectrometry was used. The obtained results may be viewed as a contribution to studies on anomalous uranium concentration within this kaolin deposit. The elevated uranium content, in comparison with its average concentration in the Earth crust, is characteristic for parent rocks of Andrzej kaolin deposit, which are granitoids of Strzegom-Sobótka massif. In connection with it, the high uranium content can be observed not only in kaolin and weakly kaolinised granitoids from the deposit in question, but also in mining waters genetically related with them.

  8. Radioecological studies of 137Cs in limnological ecosystems. 137Cs concentrations in water, sediment and biota at the lower region of the famous river in Saitama Prefecture

    International Nuclear Information System (INIS)

    Miyake, Sadaaki; Motegi, Misako; Oosawa, Takashi; Nakazawa, Kiyoaki; Ogata, Hiromitsu; Izumo, Yoshiro; Nakamura, Fumio.

    1996-01-01

    The concentrations of 137 Cs in water, sediment and biota at the lower region of the famous river in Saitama prefecture were determined in order to elucidate the radioecology of 137 Cs in limnological ecosystems. 137 Cs concentration in water was 0.10 mBq/l. 137 Cs concentrations in sediment, shellfish, Sinotaia quadratus historica (mean for 2 detectable samples), and fish, Carassius auratus cuvieri (mean for 2 detectable samples), were about 6200, 840 and 320 times higher than the concentration of the water, respectively. But 137 Cs radioactivity in the crustacea, Procambarus clarki, was significantly not detected. So, 137 Cs transfer mechanism in the limnological ecosystems was indicated in part. (author)

  9. Elasticity of superhydrous phase B at the mantle temperature and pressure: Implications for 800-km discontinuity and water flow into lower mantle

    Science.gov (United States)

    Yang, D.; Wang, W.; Wu, Z.

    2017-12-01

    Plate subduction can transport the water to the Earth's interior by forming hydrous phases and water can exert important effects on global dynamics and many processes within the deep Earth. Superhydrous phase B (ShyB), as an important candidate for transporting water into the mantle transition zone and lower mantle, is stable up to 31 GPa and will decompose into bridgmanite, periclase and water at a depth of 800 km [Komabayashi and Omori, 2006]. The decomposition of ShyB may be related to the seismic discontinuity at the depth of 800 km in Western-Pacific Subduction Zones [Liu et al., 2016; Porritt and Yoshioka, 2016]. The detail discussions on this topic require the elasticity of ShyB at the P-T conditions of the transition zone and lower mantle. In this contribution, we obtained the thermal elasticity of ShyB using first-principles calculations. ShyB shows a very low velocity and density compared to the bridgmanite and periclase, the major minerals in the lower mantle. The accumulation of ShyB will generate the low-velocity anomaly in the uppermost lower mantle. The dehydration of ShyB will cause the Vp, Vs, and density increase by 7.5%, 15.0% and 12%, respectively. It means that a slab with 10% ShyB could cause an impedance contrast of 2.7% at a depth of 800 km for shear wave. Furthermore, the released waters by the dehydration of ShyB probably migrate upward and promote the partial melt to reduce the sound velocity at shallower depth, which can further explain the low-velocity zones just above 800-km discontinuity in Western-Pacific Subduction Zones [Liu et al., 2016]. Komabayashi, T., and S. Omori (2006), Internally consistent thermodynamic data set for dense hydrous magnesium silicates up to 35GPa, 1600°C: Implications for water circulation in the Earth's deep mantle, Physics of the Earth and Planetary Interiors, 156(1-2), 89-107. Liu, Z., J. Park, and S. I. Karato (2016), Seismological detection of low-velocity anomalies surrounding the mantle transition

  10. Simulated Effects of Seasonal Ground-Water Pumpage for Irrigation on Hydrologic Conditions in the Lower Apalachicola-Chattahoochee-Flint River Basin, Southwestern Georgia and Parts of Alabama and Florida, 1999-2002

    Science.gov (United States)

    Jones, L. Elliott; Torak, Lynn J.

    2006-01-01

    To determine the effects of seasonal ground-water pumpage for irrigation, a finite-element ground-water flow model was developed for the Upper Floridan aquifer in the lower Flint River Basin area, including adjacent parts of the Chattahoochee and Apalachicola River Basins. The model simulates withdrawal from the aquifer at 3,280 irrigation, municipal, and industrial wells; stream-aquifer flow between the aquifer and 36 area streams; leakage to and from the overlying upper semiconfining unit; regional ground-water flow at the lateral boundaries of the model; and water-table recharge in areas where the aquifer is at or near land surface. Steady-state calibration to drought conditions of October 1999 indicated that the model could adequately simulate measured groundwater levels at 275 well locations and streamflow gains and losses along 53 reaches of area streams. A transient simulation having 12 monthly stress periods from March 2001 to February 2002 incorporated time-varying stress from irrigation pumpage, stream and lake stage, head in the overlying upper semiconfining unit, and infiltration rates. Analysis of simulated water budgets of the Upper Floridan aquifer provides estimates of the source of water pumped for irrigation. During October 1999, an estimated 127 million gallons per day (Mgal/d) of irrigation pumpage from the Upper Floridan aquifer in the model area were simulated to be derived from changes in: stream-aquifer flux (about 56 Mgal/d, or 44 percent); leakage to or from the upper semiconfining unit (about 49 Mgal/d, or 39 percent); regional flow (about 18 Mgal/d, or 14 percent); leakage to or from Lakes Seminole and Blackshear (about 2.7 Mgal/d, or 2 percent); and flux at the Upper Floridan aquifer updip boundary (about 1.8 Mgal/d, or 1 percent). During the 2001 growing season (May-August), estimated irrigation pumpage ranged from about 310 to 830 Mgal/ d, about 79 percent of the 12-month total. During the growing season, irrigation pumpage was

  11. 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

  12. Effect of mercury and arsenic from industrial effluents on the drinking water and comparison of the water quality of polluted and non-polluted areas: a case study of Peshawar and Lower Dir.

    Science.gov (United States)

    Ishaq, M; Jan, F Akbar; Khan, Murad Ali; Ihsanullah, I; Ahmad, I; Shakirullah, M; Roohullah

    2013-02-01

    The purpose of the present study was to find out the sources of mercury and arsenic pollution of water in the industrial area of Peshawar, the capital of Khyber Pakhtunkhwa, Pakistan. Samples of effluents, mud, and water were collected from the target area (industrial area of Peshawar), the area of water supply source, and from the less polluted area, the Lower Dir district, as the control. Hg was determined by the cold vapor generation technique, while arsenic was determined using the electrothermal atomic absorption technique. Data of the water from the industrial area were compared with that of the source area, control area, as well as with the WHO and some international drinking water quality standards. The results show that some parameters, i.e., TDS, DO, pH, and hardness, were more than the permissible limits. Textile and glass industries were found to be the major sources of Hg and As pollution. Downstream dilution of these contaminants was also observed.

  13. Effect of Nordic Walking and Water Aerobics Training on Body Composition and the Blood Flow in Lower Extremities in Elderly Women

    Directory of Open Access Journals (Sweden)

    Jasiński Ryszard

    2015-03-01

    Full Text Available Nordic walking and water aerobics are very popular forms of physical activity in the elderly population. The aim of the study was to evaluate the influence of regular health training on the venous blood flow in lower extremities and body composition in women over 50 years old. Twenty-four women of mean age 57.9 (± 3.43 years, randomly divided into three groups (Nordic walking, water aerobics, and non-training, participated in the study. The training lasted 8 weeks, with one-hour sessions twice a week. Dietary habits were not changed. Before and after training vein refilling time and the function of the venous pump of the lower extremities were measured by photoplethysmography. Body composition was determined by bioelectrical impedance. Eight weeks of Nordic walking training improved the venous blood flow in lower extremities and normalized body composition in the direction of reducing chronic venous disorder risk factors. The average values of the refilling time variable (p = 0.04, p = 0.02, respectively decreased in both the right and the left leg. After training a statistically significant increase in the venous pump function index was found only in the right leg (p = 0.04. A significant increase in fat-free mass, body cell mass and total body water was observed (p = 0.01, whereas body mass, the body mass index, and body fat decreased (p < 0.03. With regard to water aerobic training, no similar changes in the functions of the venous system or body composition were observed.

  14. Impacts of the dam-orientated water-sediment regulation scheme on the lower reaches and delta of the Yellow River (Huanghe): A review

    Science.gov (United States)

    Wang, Houjie; Wu, Xiao; Bi, Naishuang; Li, Song; Yuan, Ping; Wang, Aimei; Syvitski, James P. M.; Saito, Yoshiki; Yang, Zuosheng; Liu, Sumei; Nittrouer, Jeffrey

    2017-10-01

    The water-sediment regulation scheme (WSRS), beginning in 2002, is an unprecedented engineering effort to manage the Yellow River with the aims to mitigate the siltation both in the lower river channel and within the Xiaolangdi Reservoir utilizing the dam-regulated flood water. Ten years after its initial implementation, multi-disciplinary indicators allow us to offer a comprehensive review of this human intervention on a river-coastal system. The WSRS generally achieved its objective, including bed erosion in the lower reaches with increasing capacity for flood discharge and the mitigation of reservoir siltation. However, the WSRS presented unexpected disturbances on the delta and coastal system. Increasing grain size of suspended sediment and decreasing suspended sediment concentration at the river mouth resulted in a regime shift of sediment transport patterns that enhanced the disequilibrium of the delta. The WSRS induced an impulse delivery of nutrients and pollutants within a short period ( 20 days), which together with the altered hydrological cycle, impacted the estuarine and coastal ecosystem. We expect that the sediment yield from the loess region in the future will decrease due to soil-conservation practices, and the lower channel erosion will also decrease as the riverbed armors with coarser sediment. These, in combination with uncertain water discharge concomitant with climate change, increasing water demands and delta subsidence, will put the delta and coastal ocean at high environmental risks. In the context of global change, this work depicts a scenario of human impacts in the river basin that were transferred along the hydrological pathway to the coastal system and remotely transformed the different components of coastal environment. The synthesis review of the WSRS indicates that an integrated management of the river-coast continuum is crucially important for the sustainability of the entire river-delta system. The lessons learned from the WSRS in

  15. Spatial Heterodyne Observations of Water (SHOW) vapour in the upper troposphere and lower stratosphere from a high altitude aircraft: Modelling and sensitivity analysis

    Science.gov (United States)

    Langille, J. A.; Letros, D.; Zawada, D.; Bourassa, A.; Degenstein, D.; Solheim, B.

    2018-04-01

    A spatial heterodyne spectrometer (SHS) has been developed to measure the vertical distribution of water vapour in the upper troposphere and the lower stratosphere with a high vertical resolution (∼500 m). The Spatial Heterodyne Observations of Water (SHOW) instrument combines an imaging system with a monolithic field-widened SHS to observe limb scattered sunlight in a vibrational band of water (1363 nm-1366 nm). The instrument has been optimized for observations from NASA's ER-2 aircraft as a proof-of-concept for a future low earth orbit satellite deployment. A robust model has been developed to simulate SHOW ER-2 limb measurements and retrievals. This paper presents the simulation of the SHOW ER-2 limb measurements along a hypothetical flight track and examines the sensitivity of the measurement and retrieval approach. Water vapour fields from an Environment and Climate Change Canada forecast model are used to represent realistic spatial variability along the flight path. High spectral resolution limb scattered radiances are simulated using the SASKTRAN radiative transfer model. It is shown that the SHOW instrument onboard the ER-2 is capable of resolving the water vapour variability in the UTLS from approximately 12 km - 18 km with ±1 ppm accuracy. Vertical resolutions between 500 m and 1 km are feasible. The along track sampling capability of the instrument is also discussed.

  16. On-line micro-volume introduction system developed for lower density than water extraction solvent and dispersive liquid–liquid microextraction coupled with flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Anthemidis, Aristidis N.; Mitani, Constantina; Balkatzopoulou, Paschalia; Tzanavaras, Paraskevas D.

    2012-01-01

    Highlights: ► A dispersive liquid–liquid micro extraction method for lead and copper determination. ► A micro-volume transportation system for extractant solvent lighter than water. ► Analysis of natural water samples. - Abstract: A simple and fast preconcentration/separation dispersive liquid–liquid micro extraction (DLLME) method for metal determination based on the use of extraction solvent with lower density than water has been developed. For this purpose a novel micro-volume introduction system was developed enabling the on-line injection of the organic solvent into flame atomic absorption spectrometry (FAAS). The effectiveness and efficiency of the proposed system were demonstrated for lead and copper preconcentration in environmental water samples using di-isobutyl ketone (DBIK) as extraction solvent. Under the optimum conditions the enhancement factor for lead and copper was 187 and 310 respectively. For a sample volume of 10 mL, the detection limit (3 s) and the relative standard deviation were 1.2 μg L −1 and 3.3% for lead and 0.12 μg L −1 and 2.9% for copper respectively. The developed method was evaluated by analyzing certified reference material and it was applied successfully to the analysis of environmental water samples.

  17. VIDENTE 1.1: a graphical user interface and decision support system for stochastic modelling of water table fluctuations at a single location; includes documentation of the programs KALMAX, KALTFN, SSD and EMERALD and introductions to stochastic modelling; 2nd rev. ed

    NARCIS (Netherlands)

    Bierkens, M.F.P.; Bron, W.A.; Knotters, M.

    2002-01-01

    A description is given of the program VIDENTE. VIDENTE contains a decision support system to choose between different models for stochastic modelling of water-table depths and a graphical user interface to facilitate operating and running four implemented models: KALMAX, KALTFN, SSD and EMERALD. In

  18. Ground-based eye-safe networkable micro-pulse differential absorption and high spectral resolution lidar for water vapor and aerosol profiling in the lower troposphere

    Science.gov (United States)

    Repasky, K. S.; Spuler, S.; Hayman, M. M.; Bunn, C. E.

    2017-12-01

    Atmospheric water vapor is a greenhouse gas that is known to be a significant driver of weather and climate. Several National Research Council (NRC) reports have highlighted the need for improved water vapor measurements that can capture its spatial and temporal variability as a means to improve weather predictions. Researchers at Montana State University (MSU) and the National Center for Atmospheric Research (NCAR) have developed an eye-safe diode laser based micro-pulse differential absorption lidar (MP-DIAL) for water vapor profiling in the lower troposphere. The MP-DIAL is capable of long term unattended operation and is capable of monitoring water vapor in the lower troposphere in most weather conditions. Two MP-DIAL instruments are currently operational and have been deployed at the Front Range Air Pollution and Photochemistry Experiment (FRAPPE), the Plains elevated Convection at Night (PECAN) experiment, the Perdigão experiment, and the Land Atmosphere Feedback Experiment (LAFE). For each of these field experiments, the MP-DIAL was run unattended and provided near-continuous water vapor profiles, including periods of bright daytime clouds, from 300 m above the ground level to 4 km (or the cloud base) with 150 m vertical resolution and 5 minute temporal resolution. Three additional MP-DIAL instruments are currently under construction and will result in a network of five eye-safe MP-DIAL instruments for ground based weather and climate research experiments. Taking advantage of the broad spectral coverage and modularity or the diode based architecture, a high spectral resolution lidar (HSRL) measurement capabilities was added to the second MP-DIAL instrument. The HSRL capabilities will be operational during the deployment at the LAFE field experiment. The instrument architecture will be presented along with examples of data collected during recent field experiments.

  19. Artificial recharge of the water-table aquifer in the latian volcano in Rome province; Ricarica artificiale dalla falda acquifera presente nel vulcano laziale in Provincia di Roma

    Energy Technology Data Exchange (ETDEWEB)

    Bersani, P.; Piotti, A. [Ambito Territoriale Ottimale, Lazio Centrale, Rome (Italy)

    2001-06-01

    The zone of the Latian Volcano extends in an area of about 1.500 km{sup 2} in the south-est of Rome. This area is thickly peopled, owing to the presence of many towns (Velletri, Frascati, Albano, etc.) in the central share of the volcanic edifice. Actually the volcanic edifice of Alban Hills shows in the central and higher area, a large caldera (Tuscolana-Artemisia). This caldera has a sub-circular form wide 10 km in diameter and 75 km{sup 2} in area. The excessive groundwater drawing by wells caused the depauperation of underground resources so to produce a real crisis since 1984. To restore of water balance of the aquifer of the Latian Volcano, an important contribution could be given by the artificial recharge of the higher aquifer. This recharge could be done by allowing to meteoric water to inflitrate as much as possible in the underground by realization of an artificial lake; otherwise by making a series of little infiltration-basins together with infiltration-wells. Besides the realization of the artificial lake could give back to the landscape a characteristic component present in the past centuries until very recent times. [Italian] L'area del Vulcano Laziale si estende su una superficie di circa 1500 km{sup 2} a sud-est di Roma in un'area densamente popolata per la presenza di numerosi centri urbani (Velletri, Frascati, Albano, ecc.), ubicati nella parte centrale dell'ufficio vulcanico. Attualmente l'edificio vulcanico dei Colli Albani presenta in posizione centrale un'ampia caldera sommitale con forma subcircolare, con diametro medio di circa 10 km ed estensione di circa 75 km{sup 2}. Gli eccessivi prelievi di acqua sotterranea hanno condotto ad un impoverimento della risorsa idrica fino a determinare una vera e propria crisi manifestatasi a partire dal 1984. Per riequilibrare il bilancio idrico dell'acquifero del Vulcano Laziale, un contributo significativo potrebbe provenire dalla ricarica artificiale dell

  20. Repeatability of chemical-shift-encoded water-fat MRI and diffusion-tensor imaging in lower extremity muscles in children.

    Science.gov (United States)

    Ponrartana, Skorn; Andrade, Kristine E; Wren, Tishya A L; Ramos-Platt, Leigh; Hu, Houchun H; Bluml, Stefan; Gilsanz, Vicente

    2014-06-01

    The purpose of this study was to assess the repeatability of water-fat MRI and diffusion-tensor imaging (DTI) as quantitative biomarkers of pediatric lower extremity skeletal muscle. MRI at 3 T of a randomly selected thigh and lower leg of seven healthy children was studied using water-fat separation and DTI techniques. Muscle-fat fraction, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) values were calculated. Test-retest and interrater repeatability were assessed by calculating the Pearson correlation coefficient, intraclass correlation coefficient, and Bland-Altman analysis. Bland-Altman plots show that the mean difference between test-retest and interrater measurements of muscle-fat fraction, ADC, and FA was near 0. The correlation coefficients and intraclass correlation coefficients were all between 0.88 and 0.99 (p DTI measurements in lower extremity skeletal muscles are objective repeatable biomarkers in children. This knowledge should aid in the understanding of the number of participants needed in clinical trials when using these determinations as an outcome measure to noninvasively monitor neuromuscular disease.

  1. Using Stable Isotopes in Water Vapor to Diagnose Relationships Between Lower-Tropospheric Stability, Mixing, and Low-Cloud Cover Near the Island of Hawaii

    Science.gov (United States)

    Galewsky, Joseph

    2018-01-01

    In situ measurements of water vapor isotopic composition from Mauna Loa, Hawaii, are merged with soundings from Hilo to show an inverse relationship between the estimated inversion strength (EIS) and isotopically derived measures of lower-tropospheric mixing. Remote sensing estimates of cloud fraction, cloud liquid water path, and cloud top pressure were all found to be higher (lower) under low (high) EIS. Inverse modeling of the isotopic data corresponding to terciles of EIS conditions provide quantitative constraints on the last-saturation temperatures and mixing fractions that govern the humidity above the trade inversion. The mixing fraction of water vapor transported from the boundary layer to Mauna Loa decreases with respect to EIS at a rate of about 3% K-1, corresponding to a mixing ratio decrease of 0.6 g kg-1 K-1. A last-saturation temperature of 240 K can match all observations. This approach can be applied in other settings and may be used to test models of low-cloud climate feedbacks.

  2. Stream water quality in coal mined areas of the lower Cheat River Basin, West Virginia and Pennsylvania, during low-flow conditions, July 1997

    Science.gov (United States)

    Williams, Donald R.; Clark, Mary E.; Brown, Juliane B.

    1999-01-01

    IntroductionThe Cheat River Basin is in the Allegheny Plateau and Allegheny Mountain Sections of the Appalachian Plateau Physiographic Province (Fenneman, 1946) and is almost entirely within the state of West Virginia. The Cheat River drains an area of 1,422 square miles in Randolph, Tucker, Preston, and Monongalia Counties in West Virginia and Fayette County in Pennsylvania. From its headwaters in Randolph County, W.Va., the Cheat River flows 157 miles north to the Pennsylvania state line, where it enters the Monongahela River. The Cheat River drainage comprises approximately 19 percent of the total Monongahela River Basin. The Cheat River and streams within the Cheat River Basin are characterized by steep gradients, rock channels, and high flow velocities that have created a thrivi