Science.gov

Sample records for fresh water inflow

  1. Fresh Water Inflow and Oyster Productivity in Apalachicola Bay, FL (USA)

    EPA Science Inventory

    Apalachicola Bay lies at the mouth of the Apalachicola River, where seasonally variable freshwater inflows and shifting winds support an unusually productive and commercially important oyster fishery. While there is concern that upstream water withdrawals may impact the fishery,...

  2. Fresh Water Inflow and Oyster Productivity in Apalachicola Bay, FL (USA)

    EPA Science Inventory

    Apalachicola Bay lies at the mouth of the Apalachicola River, where seasonally variable freshwater inflows and shifting winds support an unusually productive and commercially important oyster fishery. While there is concern that upstream water withdrawals may impact the fishery,...

  3. Fresh oxygen for the Baltic Sea — An exceptional saline inflow after a decade of stagnation

    NASA Astrophysics Data System (ADS)

    Mohrholz, V.; Naumann, M.; Nausch, G.; Krüger, S.; Gräwe, U.

    2015-08-01

    The ecological state of the Baltic Sea depends crucially on sufficiently frequent, strong deep water renewal on the periodic deep water renewal events by inflow of oxygen rich saline water from the North Sea. Due to the strong density stratification these inflows are the only source for deep water ventilation. Since the early eighties of the last century the frequency of inflow events has dropped drastically from 5 to 7 major inflows per decade to only one inflow per decade. Wide spread anoxic conditions became the usual state in the central Baltic. The rare major Baltic inflow (MBI) events in 1993 and 2003 could interrupt the anoxic bottom conditions only temporarily. After more than 10 years without a major Baltic inflow events, in December 2014 a strong MBI brought large amounts of saline and well oxygenated water into the Baltic Sea. Based on observations and numerical modeling, the inflow was classified as one of the rare very strong events. The inflow volume and the amount of salt transported into the Baltic were estimated to be with 198 km3 and 4 Gt, respectively. The strength of the MBI exceeded considerably the previous 2003 event. In the list of the MBIs since 1880, the 2014 inflow is the third strongest event together with the MBI in 1913. This inflow event will most probably turn the entire Baltic deep water from anoxic to oxic conditions, with substantial spread consequences for marine life and biogeochemical cycles.

  4. Fresh Water Life.

    ERIC Educational Resources Information Center

    Kestler, Carol Susan

    1991-01-01

    Describes methodology for a fresh water life study with elementary through college age students with suggestions for proper equipment, useful guides, and other materials. Proposes an activity for the collection and study of plankton. Includes background information.(MCO)

  5. Fresh Water Life.

    ERIC Educational Resources Information Center

    Kestler, Carol Susan

    1991-01-01

    Describes methodology for a fresh water life study with elementary through college age students with suggestions for proper equipment, useful guides, and other materials. Proposes an activity for the collection and study of plankton. Includes background information.(MCO)

  6. Water Quality Assessment Dale Hollow Lake and Its Inflows,

    DTIC Science & Technology

    1986-03-01

    NATIONAL BUREAU Of STANDARDS-1963-A I B US Army Corps of Engineers Nashville District Water Quality Assessment Dale Hollow Lake and Its Inflows March...PERIOD COVERED Water Quality Assessment Final Report Dale Hollow Lake and Its Inflows 6. PERFORMING ORO. REPORT NUMBER 7. AUTHOR(a) 6. CONTRACT OR... Water Resources Center, Tennessee Tech. Univ. Box 5082 Cookeville, TN 38505 11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE U.S. Army Engineer

  7. Impact of inflow transport approximation on light water reactor analysis

    NASA Astrophysics Data System (ADS)

    Choi, Sooyoung; Smith, Kord; Lee, Hyun Chul; Lee, Deokjung

    2015-10-01

    The impact of the inflow transport approximation on light water reactor analysis is investigated, and it is verified that the inflow transport approximation significantly improves the accuracy of the transport and transport/diffusion solutions. A methodology for an inflow transport approximation is implemented in order to generate an accurate transport cross section. The inflow transport approximation is compared to the conventional methods, which are the consistent-PN and the outflow transport approximations. The three transport approximations are implemented in the lattice physics code STREAM, and verification is performed for various verification problems in order to investigate their effects and accuracy. From the verification, it is noted that the consistent-PN and the outflow transport approximations cause significant error in calculating the eigenvalue and the power distribution. The inflow transport approximation shows very accurate and precise results for the verification problems. The inflow transport approximation shows significant improvements not only for the high leakage problem but also for practical large core problem analyses.

  8. Water-quality reconnaissance of surface inflow to Utah Lake

    USGS Publications Warehouse

    Mundorff, J.C.

    1974-01-01

    This report on the quality of the major surface-water inflow to Utah Lake was prepared by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights. The purpose of the reconnaissance on which the report is based was to obtain information about (1) the general inorganic chemical characteristics of surface water throughout the drainage basins of the major streams that contribute to Utah Lake, (2) the effects of the natural environment and of present water use on the chemical characteristics, and (3) general characteristics of the sediment discharge of selected streams in the basin. This information will be useful in the operation of present water systems and in planning future water development and use.The reconnaissance of inflow to Utah Lake was limited in scope; it did not include intensive study of the effects of municipal sewage, irrigation, industry, or mining on water quality. The principal objective of the study was a general definition of water-quality characteristics throughout the major drainage areas tributary to Utah Lake. A secondary objective was the definition of specific problem areas or stream reaches in which deterioration in water quality was evident.

  9. Fresh Water Content Variability in the Arctic Ocean

    NASA Technical Reports Server (NTRS)

    Hakkinen, Sirpa; Proshutinsky, Andrey

    2003-01-01

    Arctic Ocean model simulations have revealed that the Arctic Ocean has a basin wide oscillation with cyclonic and anticyclonic circulation anomalies (Arctic Ocean Oscillation; AOO) which has a prominent decadal variability. This study explores how the simulated AOO affects the Arctic Ocean stratification and its relationship to the sea ice cover variations. The simulation uses the Princeton Ocean Model coupled to sea ice. The surface forcing is based on NCEP-NCAR Reanalysis and its climatology, of which the latter is used to force the model spin-up phase. Our focus is to investigate the competition between ocean dynamics and ice formation/melt on the Arctic basin-wide fresh water balance. We find that changes in the Atlantic water inflow can explain almost all of the simulated fresh water anomalies in the main Arctic basin. The Atlantic water inflow anomalies are an essential part of AOO, which is the wind driven barotropic response to the Arctic Oscillation (AO). The baroclinic response to AO, such as Ekman pumping in the Beaufort Gyre, and ice meldfreeze anomalies in response to AO are less significant considering the whole Arctic fresh water balance.

  10. Effects of the 2014 Major Baltic Inflow on methane dynamics in the water column of the Central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Myllykangas, Jukka-Pekka; Jilbert, Tom; Jakobs, Gunnar; Rehder, Gregor; Hietanen, Susanna

    2017-04-01

    The Baltic Sea is a brackish water body which exhibits strong salinity stratification between its almost fresh surface and the comparatively high salinity deep waters. Due to this stratification, the sub-halocline deep waters are insulated from the surface and are typically anoxic and contain large amounts of methane. Deep water renewal occurs predominantly by irregular inflow phenomena, during which specific meteorological conditions cause large amounts of oxic and highly saline North Sea water to enter the Baltic via the Danish straits. In late 2014, the third largest inflow ever recorded entered the Baltic Sea and caused considerable changes in the southern and central Baltic water column oxygen conditions and consequently also in the deep-water methane pool. We studied these changes during 2015 on six cruises spanning between March and December. Following the inflow, methane that had previously accumulated in the stagnant deep waters was largely removed over a period of several months. Based on methane oxidation rate measurements, stable isotope data and comparisons to changes in corresponding phosphate inventories, we show strong evidence that most of the methane removal observed was due microbial oxidation. The intruding water masses interacted with the old stagnant water masses, creating complex redox environments, which seemed ideal for microbial oxidation of methane. However, a considerable amount of methane was also removed by physical displacement to other parts of the Baltic Sea, the relative importance of these two process changing over time. By the end of 2015, the deep waters were turning anoxic again and methane started accumulating, indicating that the ability of the inflow to ventilate the Baltic Sea was relatively short-lived.

  11. DISPERSIBILITY OF CRUDE OIL IN FRESH WATER

    EPA Science Inventory

    The effects of surfactant composition on the ability of chemical dispersants to disperse crude oil in fresh water were investigated. The objective of this research was to determine whether effective fresh water dispersants can be designed in case this technology is ever consider...

  12. Dissolved-mineral inflow to Great Salt Lake and chemical characteristics of the salt lake brine: Summary for water years 1960, 1961, and 1964

    USGS Publications Warehouse

    Hahl, D.C.

    1968-01-01

    The investigation of dissolved-mineral inflow to Great Salt Lake during the water years 1960, 1961, and 1964 was conducted during conditions of streamflow that were representative of the lowest and the average recorded during the water years 1934-64. The study conducted during the 1960 and 1961 water years was limited to defining surface-water inflow at sites close to the lakeshore, as well as at sites used in the 1960-6 study. From these comparative data, estimates of inflow at the lakeshore were made for the 1960 and 1961 water years. During the 1964 water year, when inflow to the lake was probably representative of the 31-year period, about 800,000 acre-feet of water containing 2,200,000 tons of dissolved solids entered the lake.During the years of average streamflow, about 500,000 acre-feet of water which might be developed for culinary use, passes the lowest sampling sites on the Bear and Weber Rivers. Also, more than 90 percent of the flow near the mouths of the Bear, Weber, and Jordan Rivers would be suitable for irrigation.Sources of inflow could be selected to provide a water supply for a fresh-water lake east of Antelope Island. The supply would range from 300,000 acre-feet of water containing 800 ppm (parts per million) of dissolved solids during periods of low streamflow to 1 million acre-feet containing 500 ppm during periods of average streamflow.

  13. The MEDESS-GIB database: tracking the Atlantic water inflow

    NASA Astrophysics Data System (ADS)

    García Sotillo, Marcos; Garcia-Ladona, Emilio; Orfila, Alejandro; Rodríguez-Rubio, Pablo; Cristobal Maraver, José; Conti, Daniel; Padorno, Elena; Jiménez, José Antonio; Capó, Este; Pérez, Fernando; Sayol, Juan Manuel; de los Santos, Francisco Javier; Amo, Arancha; Rietz, Ana; Troupin, Charles; Tintore, Joaquín; Álvarez-Fanjul, Enrique

    2016-03-01

    On 9 September 2014, an intensive drifter deployment was carried out in the Strait of Gibraltar. In the frame of the MEDESS-4MS Project (EU MED Program), the MEDESS-GIB experiment consisted of the deployment of 35 satellite tracked drifters, mostly of CODE-type, equipped with temperature sensor sampling at a rate of 30 min. Drifters were distributed along and on both sides of the Strait of Gibraltar. The MEDESS-GIB deployment plan was designed as to ensure quasi-synoptic spatial coverage. To this end, four boats covering an area of about 680 NM2 in 6 h were coordinated. As far as these authors know, this experiment is the most important exercise in the area in terms of number of drifters released. Collected satellite-tracked data along drifter trajectories have been quality controlled and processed to build the presented MEDESS-GIB database. This paper reports the MEDESS-GIB data set that comprises drifter trajectories, derived surface currents and in situ SST measurements collected along the buoys tracks. This series of data is available through the PANGAEA (Data Publisher for Earth and Environmental Science) repository, with the following doi:10.1594/PANGAEA.853701. Likewise, the MEDESS-GIB data will be incorporated as part of the Copernicus Marine historical products. The MEDESS-GIB data set provides a complete Lagrangian view of the surface inflow of Atlantic waters through the Strait of Gibraltar and thus, very useful data for further studies on the surface circulation patterns in the Alboran Sea, and their links with one of the most energetic Mediterranean Sea flows: the Algerian Current.

  14. The MEDESS-GIB database: tracking the Atlantic water inflow

    NASA Astrophysics Data System (ADS)

    Sotillo, M. G.; Garcia-Ladona, E.; Orfila, A.; Rodríguez-Rubio, P.; Maraver, J. C.; Conti, D.; Padorno, E.; Jiménez, J. A.; Capó, E.; Pérez, F.; Sayol, J. M.; de los Santos, F. J.; Amo, A.; Rietz, A.; Troupin, C.; Tintore, J.; Álvarez-Fanjul, E.

    2015-11-01

    On 9 September 2014, an intensive drifter deployment was carried out in the Strait of Gibraltar. In the frame of the EU MED Program MEDESS-4MS, the MEDESS-GIB experiment consisted of the deployment of 35 satellite tracked drifters, mostly of CODE-type, equipped with temperature sensor sampling at a rate of 30 min. Drifters were distributed along and on both sides of the Strait of Gibraltar. The MEDESS-GIB deployment plan was designed as to ensure quasi-synoptic spatial coverage. To this end, 4 boats covering an area of about 680 NM2 in 6 h were coordinated. As far as authors know, this experiment is the most important exercise in the area in terms of number of drifters released. Collected satellite-tracked data along drifter trajectories have been quality controlled and processed to build the here presented MEDESS-GIB database. This paper reports the MEDESS-GIB dataset that comprises drifter trajectories, derived surface currents and in situ SST measurements collected along the buoys tracks. This series of data is available through the PANGAEA (Data Publisher for Earth and Environmental Science) repository, with the following doi:10.1594/PANGAEA.853701. Likewise, the MEDESS-GIB data will be incorporated as part of the Copernicus Marine historical products. The MEDESS-GIB dataset provides a complete Lagrangian view of the surface inflow of Atlantic waters through the Strait of Gibraltar and thus, very useful data for further studies on the surface circulation patterns in the Alboran Sea, and their links with one of the most energetic Mediterranean Sea flows: the Algerian Current.

  15. Dispersibility of crude oil in fresh water.

    PubMed

    Wrenn, B A; Virkus, A; Mukherjee, B; Venosa, A D

    2009-06-01

    The effects of surfactant composition on the ability of chemical dispersants to disperse crude oil in fresh water were investigated. The objective of this research was to determine whether effective fresh water dispersants can be designed in case this technology is ever considered for use in fresh water environments. Previous studies on the chemical dispersion of crude oil in fresh water neither identified the dispersants that were investigated nor described the chemistry of the surfactants used. This information is necessary for developing a more fundamental understanding of chemical dispersion of crude oil at low salinity. Therefore, we evaluated the relationship between surfactant chemistry and dispersion effectiveness. We found that dispersants can be designed to drive an oil slick into the freshwater column with the same efficiency as in salt water as long as the hydrophilic-lipophilic balance is optimum.

  16. Assessment of long time series of atmospheric circulation patterns forcing inflows of saline water to the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Post, Piia; Lehmann, Andreas

    2017-04-01

    Sporadic inflows of saline waters are very important to maintain the salt balance and favorable conditions for life in the entire Baltic Sea. At other times the Baltic Sea water exchange with the North Sea through two narrow and shallow straits is highly restricted and due to the high fresh water runoff from the catchment area, outflow conditions are generally dominating. Inflow events, which carry enough saline water into the Baltic to reach the bottom of the central basins, are called major Baltic inflows (MBI). During the last 4 decades, the number of MBI-s per decade has gone down from 4-5 to only one, what has generated hypoxia in large volumes of the Baltic deeps. There are no significant changes in the time-series of the general number of inflows, the decrease is only in MBI-s. The trigger of a Baltic inflows lies in the atmosphere and the direct atmospheric forcing consists of two phases: at first high pressure with easterly winds lasts over the Baltic Sea region, what is followed by strong westerlies. The intensity of the event depends on the persistence and strength of both phases and how closely these come after each other. There are also some anomalies in the atmospheric circulation during the whole season with the event compared to mean situation, but these results are not so distinct. At the same time for prediction of MBI-s longer term factors that favor the MBI-s are very important. The other source of predictability lies in the upper atmospheric levels as the signal of transformation in the atmospheric circulation starts from up. That means that if we want to detect or even predict MBI-s from atmospheric forcing side we should be flexible and capable to describe atmospheric circulation in the whole atmospheric column with varying resolution in time and space. This sounds as a classical synoptic climatological task. Availability of more than century-long reanalysed time series gives us opportunity to study the variability of atmospheric forcing of

  17. Establishing the Global Fresh Water Sensor Web

    NASA Technical Reports Server (NTRS)

    Hildebrand, Peter H.

    2005-01-01

    This paper presents an approach to measuring the major components of the water cycle from space using the concept of a sensor-web of satellites that are linked to a data assimilation system. This topic is of increasing importance, due to the need for fresh water to support the growing human population, coupled with climate variability and change. The net effect is that water is an increasingly valuable commodity. The distribution of fresh water is highly uneven over the Earth, with both strong latitudinal distributions due to the atmospheric general circulation, and even larger variability due to landforms and the interaction of land with global weather systems. The annual global fresh water budget is largely a balance between evaporation, atmospheric transport, precipitation and runoff. Although the available volume of fresh water on land is small, the short residence time of water in these fresh water reservoirs causes the flux of fresh water - through evaporation, atmospheric transport, precipitation and runoff - to be large. With a total atmospheric water store of approx. 13 x 10(exp 12)cu m, and an annual flux of approx. 460 x 10(exp 12)cu m/y, the mean atmospheric residence time of water is approx. 10 days. River residence times are similar, biological are approx. 1 week, soil moisture is approx. 2 months, and lakes and aquifers are highly variable, extending from weeks to years. The hypothesized potential for redistribution and acceleration of the global hydrological cycle is therefore of concern. This hypothesized speed-up - thought to be associated with global warming - adds to the pressure placed upon water resources by the burgeoning human population, the variability of weather and climate, and concerns about anthropogenic impacts on global fresh water availability.

  18. Searching for storm water inflows in foul sewers using fibre-optic distributed temperature sensing.

    PubMed

    Schilperoort, Rémy; Hoppe, Holger; de Haan, Cornelis; Langeveld, Jeroen

    2013-01-01

    A major drawback of separate sewer systems is the occurrence of illicit connections: unintended sewer cross-connections that connect foul water outlets from residential or industrial premises to the storm water system and/or storm water outlets to the foul sewer system. The amount of unwanted storm water in foul sewer systems can be significant, resulting in a number of detrimental effects on the performance of the wastewater system. Efficient removal of storm water inflows into foul sewers requires knowledge of the exact locations of the inflows. This paper presents the use of distributed temperature sensing (DTS) monitoring data to localize illicit storm water inflows into foul sewer systems. Data results from two monitoring campaigns in foul sewer systems in the Netherlands and Germany are presented. For both areas a number of storm water inflow locations can be derived from the data. Storm water inflow can only be detected as long as the temperature of this inflow differs from the in-sewer temperatures prior to the event. Also, the in-sewer propagation of storm and wastewater can be monitored, enabling a detailed view on advection.

  19. Model simulation of inflow water to the Baltic Sea based on ¹²⁹I.

    PubMed

    Yi, P; Chen, X G; Bao, D X; Qian, R Z; Aldahan, A; Tian, F Y; Possnert, G; Bryhn, A C; Gu, T F; Hou, X L; He, P; Yu, Z B; Wang, B

    2013-12-01

    The semi-enclosed Baltic Sea represents a vital economic and recreational resource for more than 90 million people inhabiting its coasts. Extensive contamination of this sea by a variety of anthropogenic pollutants has raised the concern of the people in the region. Quantifying seawater inflow is crucial for estimating potential environmental risks as well as to find the best remedial strategy. We present here a model to estimate water inflow from the North Sea to the Baltic Sea by utilizing ¹²⁹I as a tracer. The results predicted inflow range of 230-450 km³/y with best fit value around 330 km³/y from the North Sea to the Baltic Sea during 1980-1999. Despite limited time series data on ¹²⁹I, the model presented here demonstrates a new management tool for the Baltic Sea to calculate inflow water compared to conventional methods (such as salinity, temperature and hydrographic models).

  20. Influence of Ramjets' water inflow on supercavity shape and cavitator drag characteristic

    NASA Astrophysics Data System (ADS)

    Huang, Chuang; Dang, Jianjun; Luo, Kai; Li, Daijin; Wang, Zhiqiang

    2017-06-01

    Water ramjets using outer water as an oxidizer have been demonstrated as a potential propulsion mode for underwater High Speed Supercavitating Vehicles (HSSVs) because of their higher energy density, power density, and specific impulse, but water flux changes the shapes of supercavity. To uncover the cavitator drag characteristics and the supercavity shape of HSSVs with water inflow for ramjets, supercavitation flows around a disk cavitator with inlet hole are studied using the homogenous model. By changing the water inflow in the range of 0-10 L/s through cavitators having different water inlet areas, a series of numerical simulations of supercavitation flows was performed. The water inflow flux of ramjets significantly influences the drag features of disk cavitators and the supercavity shape, but it has little influence on the slender ratio of supercavitaty. Furthermore, as the water inlet area increases, the drag coefficient of the cavitators' front face decreases, but this increase does not influence the diameter of the supercavity's maximum cross section and the drag coefficient of the entire cavitator significantly. In addition, with increasing water flux of the ramjet, both the drag coefficient of cavitators and the maximum diameter of supercavities decrease stably. This research will be helpful for layout optimization and supercavitaty scheme design of HSSVs with water inflow for ramjets.

  1. Estimating ground-water inflow to lakes in central Florida using the isotope mass-balance approach

    USGS Publications Warehouse

    Sacks, Laura A.

    2002-01-01

    The isotope mass-balance approach was used to estimate ground-water inflow to 81 lakes in the central highlands and coastal lowlands of central Florida. The study area is characterized by a subtropical climate and numerous lakes in a mantled karst terrain. Ground-water inflow was computed using both steady-state and transient formulations of the isotope mass-balance equation. More detailed data were collected from two study lakes, including climatic, hydrologic, and isotopic (hydrogen and oxygen isotope ratio) data. For one of these lakes (Lake Starr), ground-water inflow was independently computed from a water-budget study. Climatic and isotopic data collected from the two lakes were similar even though they were in different physiographic settings about 60 miles apart. Isotopic data from all of the study lakes plotted on an evaporation trend line, which had a very similar slope to the theoretical slope computed for Lake Starr. These similarities suggest that data collected from the detailed study lakes can be extrapolated to the rest of the study area. Ground-water inflow computed using the isotope mass-balance approach ranged from 0 to more than 260 inches per year (or 0 to more than 80 percent of total inflows). Steady-state and transient estimates of ground-water inflow were very similar. Computed ground-water inflow was most sensitive to uncertainty in variables used to calculate the isotopic composition of lake evaporate (isotopic compositions of lake water and atmospheric moisture and climatic variables). Transient results were particularly sensitive to changes in the isotopic composition of lake water. Uncertainty in ground-water inflow results is considerably less for lakes with higher ground-water inflow than for lakes with lower ground-water inflow. Because of these uncertainties, the isotope mass-balance approach is better used to distinguish whether ground-water inflow quantities fall within certain ranges of values, rather than for precise

  2. Improving estimates of riverine fresh water into the Mediterranean sea

    NASA Astrophysics Data System (ADS)

    Wang, Fuxing; Polcher, Jan

    2017-04-01

    Estimating the freshwater input from the continents into the Mediterranean sea is a difficult endeavor due to the uncertainties from un-gauged rivers, human activities, and measurement of water flow at river outlet. One approach to estimate the freshwater inflow into the Mediterranean sea is based on the observed flux (about 63% available) and a simple annual water balance for rivers without observations (ignoring human usage and other processes). This method is the basis of most water balance studies of the Mediterranean sea and oceanic modelling activities, but it only provides annual mean values with a very strong assumption. Another approach is done by forcing a state of the art land surface model (LSM) with bias corrected atmospheric conditions. This method can estimate total fresh water flowing into the Mediterranean at daily scale but with all the caveats associated to models. We use data assimilation techniques by merging data between the model output (ORCHIDEE LSM developed at Institut Pierre Simon Laplace) and the observed river discharge from Global Runoff Data Center (GRDC) to correct the modelled fluxes with observations over the entire basin. Over each sub watershed, the GRDC data (if available) are applied to correct model simulated river discharge. This will allow to compensate for systematic errors of model or missing processes and provide estimates of the riverine input into the sea at high temporal and spatial resolution. We will analyze the freshwater inflow into the Mediterranean obtained here with different approaches reported in previous paper. The new estimates will serve for ocean modelling and water balance studies of the region.

  3. Methods for Chemical Analysis of Fresh Waters.

    ERIC Educational Resources Information Center

    Golterman, H. L.

    This manual, one of a series prepared for the guidance of research workers conducting studies as part of the International Biological Programme, contains recommended methods for the analysis of fresh water. The techniques are grouped in the following major sections: Sample Taking and Storage; Conductivity, pH, Oxidation-Reduction Potential,…

  4. Methods for Chemical Analysis of Fresh Waters.

    ERIC Educational Resources Information Center

    Golterman, H. L.

    This manual, one of a series prepared for the guidance of research workers conducting studies as part of the International Biological Programme, contains recommended methods for the analysis of fresh water. The techniques are grouped in the following major sections: Sample Taking and Storage; Conductivity, pH, Oxidation-Reduction Potential,…

  5. Hot water, fresh beer, and salt

    NASA Astrophysics Data System (ADS)

    Crawford, Frank S.

    1990-11-01

    In the ``hot chocolate effect'' the best musical scales (those with the finest tone quality, largest range, and best tempo) are obtained by adding salt to a glass of hot water supersaturated with air. Good scales can also be obtained by adding salt to a glass of freshly opened beer (supersaturated with CO2) provided you first (a) get rid of much of the excess CO2 so as to produce smaller, hence slower, rising bubbles, and (b) get rid of the head of foam, which damps the standing wave and ruins the tone quality. Finally the old question, ``Do ionizing particles produce bubbles in fresh beer?'' is answered experimentally.

  6. The Iceland-Faroe inflow of Atlantic water to the Nordic Seas [review article

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Østerhus, S.; Hátún, H.; Kristiansen, R.; Larsen, K. M. H.

    2003-12-01

    The flow of Atlantic water between Iceland and the Faroe Islands is one of three current branches flowing from the Atlantic Ocean into the Nordic Seas across the Greenland-Scotland Ridge. By the heat that it carries along, it keeps the subarctic regions abnormally warm and by its import of salt, it helps maintain a high salinity and hence density in the surface waters as a precondition for thermohaline ventilation. From 1997 to 2001, a number of ADCPs have been moored on a section going north from the Faroes, crossing the inflow. Combining these measurements with decade-long CTD observations from research vessel cruises along this section, we compute the fluxes of water (volume), heat, and salt. For the period June 1997-June 2001, we found the average volume flux of Atlantic water to be 3.5±0.5 Sv (1 Sv=10 6 m 3·s -1). When compared to recent estimates of the other branches, this implies that the Iceland-Faroe inflow is the strongest branch in terms of volume flux, transporting 47% of the total Atlantic inflow to the Arctic Mediterranean (Nordic Seas and Arctic Ocean with shelf areas). If all of the Atlantic inflow were assumed to be cooled to 0 °C, before returning to the Atlantic, the Iceland-Faroe inflow carries a heat flux of 124±15 TW (1 TW=10 12 W), which is about the same as the heat carried by the inflow through the Faroe-Shetland Channel. The Iceland-Faroe Atlantic water volume flux was found to have a negligible seasonal variation and to be remarkably stable with no reversals, even on daily time scales. Out of a total of 1348 daily flux estimates, not one was directed westwards towards the Atlantic.

  7. Groundwater infiltration, surface water inflow and sewerage exfiltration considering hydrodynamic conditions in sewer systems.

    PubMed

    Karpf, Christian; Hoeft, Stefan; Scheffer, Claudia; Fuchs, Lothar; Krebs, Peter

    2011-01-01

    Sewer systems are closely interlinked with groundwater and surface water. Due to leaks and regular openings in the sewer system (e.g. combined sewer overflow structures with sometimes reverse pressure conditions), groundwater infiltration and surface water inflow as well as exfiltration of sewage take place and cannot be avoided. In the paper a new hydrodynamic sewer network modelling approach will be presented, which includes--besides precipitation--hydrographs of groundwater and surface water as essential boundary conditions. The concept of the modelling approach and the models to describe the infiltration, inflow and exfiltration fluxes are described. The model application to the sewerage system of the City of Dresden during a flood event with complex conditions shows that the processes of infiltration, exfiltration and surface water inflows can be described with a higher reliability and accuracy, showing that surface water inflow causes a pronounced system reaction. Further, according to the simulation results, a high sensitivity of exfiltration rates on the in-sewer water levels and a relatively low influence of the dynamic conditions on the infiltration rates were found.

  8. Spiniferites cruciformis: a fresh water dinoflagellate cyst?

    PubMed

    Kouli, K; Brinkhuis, H; Dale, B

    2001-04-01

    Palynological studies of cored lacustrine sediments from the late Quaternary of Lake Kastoria, northern Greece, revealed a Late Glacial interval with abundant dinoflagellate cysts. Cyst assemblages include two identifiable species, Spiniferites cruciformis and Gonyaulax apiculata. The presence of the fresh water species G. apiculata is consistent with the lacustrine setting of these deposits, but that of S. cruciformis is anomalous. Previously, this species has only been recorded in abundance from presumed brackish marine sediments from the Black Sea and Marmara Sea sediments where geochemical data clearly record brackish salinities. Therefore, it has been regarded as a low salinity cyst type with a wide range of morphological variation that some workers have suggested to reflect salinity fluctuations. Specimens from Greece display only part of the range of morphological variability previously described from these (brackish) marine settings. Encountered morphological variation includes ellipsoidal/pentameral and cruciform endocyst shapes with rare intermediate shapes, and highly variable septa development. Specimens characterized by extremely reduced ornamentation known from (brackish) marine environments have not been recorded. Our records of S. cruciformis indicate that: (1) it could thrive in fresh water conditions; and (2) that apparently most of the strong morphological variations of the cysts are an intrinsic phenomenon for this taxon, and may only partly be linked to salinity variations as suggested earlier. We suggest that S. cruciformis essentially is a fresh water taxon, and that its records in (brackish) marine environments, with the exception of specimens with strongly reduced ornamentation, may be due to transportation, to short-lived fresh water surface conditions in such environments, or to tolerance of the species to brackish conditions.

  9. View from southwest to northeast of PAR site fresh water ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from southwest to northeast of PAR site fresh water pump house - Stanley R. Mickelsen Safeguard Complex, Fresh Water Pump House, In Limited Access Area, on Patrol Road next to Open Storage Reservoir No. 736, Nekoma, Cavalier County, ND

  10. Global modeling of fresh surface water temperature

    NASA Astrophysics Data System (ADS)

    Bierkens, M. F.; Eikelboom, T.; van Vliet, M. T.; Van Beek, L. P.

    2011-12-01

    Temperature determines a range of water physical properties, the solubility of oxygen and other gases and acts as a strong control on fresh water biogeochemistry, influencing chemical reaction rates, phytoplankton and zooplankton composition and the presence or absence of pathogens. Thus, in freshwater ecosystems the thermal regime affects the geographical distribution of aquatic species through their growth and metabolism, tolerance to parasites, diseases and pollution and life history. Compared to statistical approaches, physically-based models of surface water temperature have the advantage that they are robust in light of changes in flow regime, river morphology, radiation balance and upstream hydrology. Such models are therefore better suited for projecting the effects of global change on water temperature. Till now, physically-based models have only been applied to well-defined fresh water bodies of limited size (e.g., lakes or stream segments), where the numerous parameters can be measured or otherwise established, whereas attempts to model water temperature over larger scales has thus far been limited to regression type of models. Here, we present a first attempt to apply a physically-based model of global fresh surface water temperature. The model adds a surface water energy balance to river discharge modelled by the global hydrological model PCR-GLOBWB. In addition to advection of energy from direct precipitation, runoff and lateral exchange along the drainage network, energy is exchanged between the water body and the atmosphere by short and long-wave radiation and sensible and latent heat fluxes. Also included are ice-formation and its effect on heat storage and river hydraulics. We used the coupled surface water and energy balance model to simulate global fresh surface water temperature at daily time steps on a 0.5x0.5 degree grid for the period 1970-2000. Meteorological forcing was obtained from the CRU data set, downscaled to daily values with ECMWF

  11. [Relationship Between Agricultural Land and Water Quality of Inflow River in Erhai Lake Basin].

    PubMed

    Pang, Yan; Xiang, Song; Chu, Zhao-sheng; Xue, Li-qiang; Ye, Bi-bi

    2015-11-01

    We studied the relationship between agricultural land and water quality of inflow river in Erhai Lake Basin, by means of spatial and statistical analysis, from the perspective of comprehensive agricultural land and the area percentage of different types of agricultural land. The obtained results indicated that inflow water quality showed a significant spatial difference, the inflow TP pollution in the western inflow rivers of Erhai Basin was serious. The major pollution indicators in the northern and southern inflow rivers (except for D3) were organic matter and nitrogen. The area percentage of agricultural land had a significantly indicative effect on the water quality of inflow river. The area percentage of comprehensive agricultural land negatively correlated with permanganate index, NH4(+) -N, TN and TP contents in wet season, the correlation coefficients were - 0.859, - 0.565, - 0.693, - 0.181. It negatively correlated with permanganate index and NH4(+) -N content in dry season, the correlation coefficients were - 0.384, - 0.328. It had positive relationships with and TN, TP content in dry season, the correlation coefficients were 0.221 and 0.146. The area percentage of different types of agricultural land had an obviously indicative effect on the inflow water quality. Farmland positively correlated with TN and TP contents both in wet and dry seasons. The correlation coefficients between farmland and TN, TP were 0.252, 0.581 in rainy season and were 0.149, 0.511 in dry season. It had positive and negative relationships with permanganate index, NH4(+) -N content in wet season and dry season, respectively. The correlation coefficients between farmland and permanganate index, NH4(+) -N were 0.388, 0.053 in rainy season and were -0.137, -0.147 in dry season. Forest land exhibited an opposite performance to that of farmland. The correlation coefficients between forest land and TN, TP, permanganate index, NH4(+) -N were - 0.526, - 0.275, - 0.469, -0.155 in rainy

  12. Environmental and Water Quality Operational Studies. Fluorometric Techniques for Tracing Reservoir Inflows.

    DTIC Science & Technology

    1984-04-01

    environments such as rivers, lakes , and cooling ponds as well, providing one considers the assumptions upon which the methods were based. 4 PART II: FLUORESCENT...waters and a plunging inflow to Lake Mead. c. Kennedy, Gunkel, and Carlile (1983)--A study of the chem- ical and physical changes that occurred in a...parcel of water as it moved through and mixed within West Point Lake , Georgia. d. Sutron Corporation (1980)--An investigation of mixing of the

  13. Hot water, fresh beer, and salt

    SciTech Connect

    Crawford, F.S. Physics Department, University of California, Berkeley, CA )

    1990-11-01

    In the hot chocolate effect'' the best musical scales (those with the finest tone quality, largest range, and best tempo) are obtained by adding salt to a glass of hot water supersaturated with air. Good scales can also be obtained by adding salt to a glass of freshly opened beer (supersaturated with CO{sub 2}) provided you first (a) get rid of much of the excess CO{sub 2} so as to produce smaller, hence slower, rising bubbles, and (b) get rid of the head of foam, which damps the standing wave and ruins the tone quality. Finally the old question, Do ionizing particles produce bubbles in fresh beer '' is answered experimentally.

  14. Power, fresh water, and food from cold, deep sea water.

    PubMed

    Othmer, D F; Roels, O A

    1973-10-12

    Many times more solar heat energy accumulates in the vast volume of warm tropic seas than that produced by all of our power plants. The looming energy crisis causes a renewal of interest in utilizing this stored solar heat to give, in addition to electric power, vast quantities of fresh water. Warm surface water, when evaporated, generates steam, to power a turbine, then fresh water when the steam is condensed by the cold water. A great increase in revenues over that from power and fresh water is shown by a substantial mariculture pilot plant. Deep sea water contains large quantities of nutrients. These feed algae which feed shellfish, ultimately shrimps and lobsters, in shallow ponds. Wastes grow seaweed of value; and combined revenues from desalination, power generation, and mariculture will give substantial profit.

  15. Water flow in fractured rock masses: numerical modeling for tunnel inflow assessment

    NASA Astrophysics Data System (ADS)

    Gattinoni, P.; Scesi, L.; Terrana, S.

    2009-04-01

    Water circulation in rocks represents a very important element to solve many problems linked with civil, environmental and mining engineering. In particular, the interaction of tunnelling with groundwater has become a very relevant problem not only due to the need to safeguard water resources from impoverishment and from the pollution risk, but also to guarantee the safety of workers and to assure the efficiency of the tunnel drainage systems. The evaluation of the hydrogeological risk linked to the underground excavation is very complex, either for the large number of variables involved or for the lack of data available during the planning stage. The study is aimed to quantify the influence of some geo-structural parameters (i.e. discontinuities dip and dip direction) on the tunnel drainage process, comparing the traditional analytical method to the modeling approach, with specific reference to the case of anisotropic rock masses. To forecast the tunnel inflows, a few Authors suggest analytic formulations (Goodman et al., 1965; Knutsson et al., 1996; Ribacchi et al., 2002; Park et al., 2008; Perrochet et al., 2007; Cesano et al., 2003; Hwang et al., 2007), valid for infinite, homogeneous and isotropic aquifer, in which the permeability value is given as a modulus of equivalent hydraulic conductivity Keq. On the contrary, in discontinuous rock masses the water flow is strongly controlled by joints orientation, by their hydraulic characteristics and by rocks fracturing conditions. The analytic equations found in the technical literature could be very useful, but often they don't reflect the real phenomena of the tunnel inflow in rock masses. Actually, these equations are based on the hypothesis of homogeneous aquifer, and then they don't give good agreement for an heterogeneous fractured medium. In this latter case, the numerical modelling could provide the best results, but only with a detailed conceptual model of the water circulation, high costs and long

  16. [Microbial indicators and fresh water quality assessment].

    PubMed

    Briancesco, Rossella

    2005-01-01

    Traditionally, the microbiological quality of waters has been measured by the analysis of indicator microorganisms. The article reviews the sanitary significance of traditional indicators of faecal contamination (total coliforms, faecal coliforms and faecal streptococci) and points out their limits. For some characteristics Escherichia coli may be considered a more useful indicator then faecal coliforms and recently it has been included in all recent laws regarding fresh, marine and drinking water. A clearer taxonomic definition of faecal streptococci evidenced the difficulty into defining a specific standard methodology of enumeration and suggested the more suitable role of enterococci as indicator microorganisms. Several current laws require the detection of enterococci. The resistance of Clostridium perfringens spores may mean that they would serve as a useful indicator of the sanitary quality of sea sediments.

  17. Using density difference to store fresh water in saline subsurface

    NASA Astrophysics Data System (ADS)

    van Ginkel, M.; Olsthoorn, Th. N.; des Tombe, B.

    2012-04-01

    The storage of fresh water in the subsurface for later recovery and use (Aquifer Storage and Recovery) is becoming more and more important in the coming decades for seasonal or emergency storage, especially in the light of climate change and increasing population. However, fresh water storage in a saline subsurface poses a challenge: the initially vertical interface between injected fresh and native salt water is unstable and tends to rotate. The injected fresh water tends to float upward on top of native salt water, where it becomes hard or impossible to recover at a later stage. A wide body of literature exists about this buoyancy effect that is caused by the density difference between fresh and salt water. Yet, very few papers focus on solutions to this problem. In this paper we propose a storage principle to overcome this buoyancy problem by actually using the density difference to keep the fresh water in place, by combining salt water extraction and impermeable barriers. This technique seems promising and could solve many local fresh water storage problems. It is especially applicable in shallow water table aquifers for the storage of fresh water below parks and arable land or for seasonal storage of desalinated water. We performed laboratory-scale experiments and numerical modelling to study the dynamic behaviour of a fresh water bubble stored in saline subsurface using the technique of salt water extraction and impermeable barriers; including effects of operation dynamics, groundwater flow, and diffusion, dispersion and density differences.

  18. Variability of river discharge and Atlantic-water inflow at the Laptev Sea continental margin during the past 15,000 years: implications from maceral and biomarker records

    NASA Astrophysics Data System (ADS)

    Boucsein, B.; Fahl, K.; Stein, R.

    2000-08-01

    In order to reconstruct the depositional environment from the Laptev Sea continental slope and shelf during the past 15,000 years BP maceral analysis was carried out on two sediment cores (PS2458-4, PS2725-5) and compared with organic-geochemical parameters. During the transition from the Last Glacial to the Holocene the environment of the Laptev Sea shelf was controlled by the post-glacial sea level rise, variations in river discharge, surface-water productivity, and Atlantic-water inflow along the Eurasian continental margin. Based on our results, we identify the following significant changes of the environment: (a) at approximately 13,500 years BP the first step of deglaciation (Termination 1a) is documented by the deposition of marine and fresh-water organic matter; (b) at approximately 10,400 years BP the first post-glacial influence of Atlantic-water inflow along the Eastern Laptev Sea continental margin is indicated by an increase in marine organic matter; (c) at the beginning of the Holocene an increased fluvial supply is documented by an increase in fresh-water alginite; and (d) since 9500-8000 years BP modern marine conditions are established at the Laptev Sea continental margin as documented in increased amounts of marine macerals, biomarkers (dinosterol, brassicasterol, short-chain fatty acids), and dinoflagellate cysts.

  19. On the spatial coherence of the Atlantic Water inflow across the Nordic Seas

    NASA Astrophysics Data System (ADS)

    Herbaut, Christophe; Houssais, Marie-Noëlle; Close, Sally; Blaizot, Anne-Cécile

    2017-05-01

    The covariability of the Atlantic Water (AW) branches in the Nordic Seas is investigated over the period 1979-2012 using an eddy permitting model. A noticeable circulation change is found in the mid-1990s. Prior to the mid-1990s, the leading mode of variability defines a large-scale pattern, with concomitant variations in the Atlantic Water (AW) inflow in the Faroe-Shetland Channel (FSC), the Norwegian Atlantic Slope Current (NwASC), the AW inflow to the Barents Sea, and the West Spitsbergen Current (WSC). After the mid-1990s, the covariability between the NwASC and the AW inflow in both the FSC and the WSC is lost. Consequently, the northern Barents Sea circulation anomaly pattern, which is present throughout the full period, becomes the leading mode of circulation in the northern Nordic Seas after the mid-1990s. The circulation change of the mid-1990s appears to be linked to a weakening of the southwesterly wind anomalies in Norwegian Sea, as the northern center of action of the first mode of sea level pressure weakens. Passive tracer experiments suggest that this circulation change may be accompanied by increased heat transfer from the AW current to the interior Nordic Seas. This in turn may have limited the influence of the recently observed AW warming in the Iceland-Scotland Passage on the NwASC downstream.

  20. Evapotranspiration and water balance of an anthropogenic coastal desert wetland: responses to fire, inflows and salinities

    USGS Publications Warehouse

    Glenn, Edward P.; Mexicano, Lourdes; Garcia-Hernandez, Jaqueline; Nagler, Pamela L.; Gomez-Sapiens, Martha M.; Tang, Dawei; Lomeli, Marcelo A.; Ramírez-Hernández, Jorge; Zamora-Arroyo, Francisco

    2013-01-01

    Evapotranspiration (ET) and other water balance components were estimated for Cienega de Santa Clara, an anthropogenic brackish wetland in the delta of the Colorado River in Mexico. The marsh is in the Biosphere Reserve of the Upper Gulf of California and Delta of the Colorado River, and supports a high abundance and diversity of wildlife. Over 95% of its water supply originates as agricultural drain water from the USA, sent for disposal in Mexico. This study was conducted from 2009 to 2011, before, during and after a trial run of the Yuma Desalting Plant in the USA, which will divert water from the wetland and replace it with brine from the desalting operation. The goal was to estimate the main components in the water budget to be used in creating management scenarios for this marsh. We used a remote sensing algorithm to estimate ET from meteorological data and Enhanced Vegetation Index values from the Moderate Resolution Imaging Spectrometer (MODIS) sensors on the Terra satellite. ET estimates from the MODIS method were then compared to results from a mass balance of water and salt inflows and outflows over the study period. By both methods, mean annual ET estimates ranged from 2.6 to 3.0 mm d−1, or 50 to 60% of reference ET (ETo). Water entered at a mean salinity of 2.6 g L−1 TDS and mean salinity in the wetland was 3.73 g L−1 TDS over the 33 month study period. Over an annual cycle, 54% of inflows supported ET while the rest exited the marsh as outflows; however, in winter when ET was low, up to 90% of the inflows exited the marsh. An analysis of ET estimates over the years 2000–2011 showed that annual ET was proportional to the volume of inflows, but was also markedly stimulated by fires. Spring fires in 2006 and 2011 burned off accumulated thatch, resulting in vigorous growth of new leaves and a 30% increase in peak summer ET compared to non-fire years. Following fires, peak summer ET estimates were equal to ETo, while in non-fire years peak ET was

  1. Water quality trends at inflows to Everglades National Park, 1977-2005.

    PubMed

    Hanlon, E A; Fan, X H; Gu, B; Migliaccio, K W; Li, Y C; Dreschel, T W

    2010-01-01

    Restoration of the Florida Everglades is important for the health of the natural system, including both the "River of Grass" and its downstream estuaries. Water quality improvement is one indicator of successful restoration in this complex ecosystem. Using the period of record of 1977 through 2005, we evaluated data from seven inflow sites to the Everglades National Park (ENP) for temporal trends of various forms of phosphorus (P) and nitrogen (N) and analyzed them using principal component analysis and factor analysis without flow adjustments. Locally estimated scatter plot smoothing (LOESS) trend lines identified two inflection points (three time periods) of changing trend in total P (TP) concentration at the seven sites. Results indicated that overall water quality in ENP inflow improved from 1977 to 2005, with significant downward trends in TP concentration. The overall trend ofTP is probably mediated by hydrology, which is evident by a negative relationship between flow and annual average TP concentration at the majority of stations within the available data, although additional changes in vegetation due to hydroperiod may have some effects. Total N (TN), total Kjeldahl N, and total organic N concentrations also generally decreased at inflow sites. Water quality standards for TP, TN, and NH4+ -N were exceeded at selected sites during the study period. Principle component analysis and factor analysis detected a grouping of sampling sites related to the water delivery system that could be used as indicators to better manage monitoring resources. Study results suggest that water quality data analyses could provide additional insight into the success of a restoration management plan and on how monitoring may be modified for more efficient use ofresources.

  2. Fresh water balance of the Gulf Stream system in a regional model study

    NASA Astrophysics Data System (ADS)

    Gerdes, R.; Biastoch, A.; Redler, R.

    We investigate the dependence of surface fresh water fluxes in the Gulf Stream and North Atlantic Current (NAC) area on the position of the stream axis which is not well represented in most ocean models. To correct this shortcoming, strong unrealistic surface fresh water fluxes have to be applied that lead to an incorrect salt balance of the current system. The unrealistic surface fluxes required by the oceanic component may force flux adjustments and may cause fictitious long-term variability in coupled climate models. To identify the important points in the correct representation of the salt balance of the Gulf Stream a regional model of the northwestern part of the subtropical gyre has been set up. Sensitivity studies are made where the westward flow north of the Gulf Stream and its properties are varied. Increasing westward volume transport leads to a southward migration of the Gulf Stream separation point along the American coast. The salinity of the inflow is essential for realistic surface fresh water fluxes and the water mass distribution. The subpolar-subtropical connection is important in two ways: The deep dense flow from the deep water mass formation areas sets up the cyclonic circulation cell north of the Gulf Stream. The surface and mid depth flow of fresh water collected at high northern latitudes is mixed into the Gulf Stream and compensates for the net evaporation at the surface.

  3. Downstream changes of water quality in a lowland river due to groundwater inflows.

    NASA Astrophysics Data System (ADS)

    Zieba, Damian; Bar-Michalczyk, Dominika; Kania, Jarosław; Malina, Grzegorz; Michalczyk, Tomasz; Rozanski, Kazimierz; Witczak, Stanislaw; Wachniew, Przemyslaw; Zurek, Anna J.

    2016-04-01

    The Kocinka catchment (ca. 250 km2) in southern Poland receives substantial inflows of groundwater from a major fissured-carbonate aquifer polluted with nitrates originating from agriculture and domestic sewage. The 40 km long Kocinka river reveals large spatial variations in physical and chemical water properties with large downstream changes of nitrate concentrations. Detailed longitudinal surveys of such water characteristics as nitrate concentration, water temperature, pH, electric conductivity, stable isotopic composition, tritium concentration were performed in order to identify and quantify groundwater inflows. The river gains groundwater down to the 25 km from the source and a looses water further downstream. The subsequent increase and decrease of nitrate concentration in the upper and middle reaches of the river are caused by inflows of the, respectively, polluted and non-polluted groundwaters. The range of such changes can be even five-fold while the drop of nitrate concentration along the semi natural, 18 km long, lower reach where the river is well connected to its riparian and hyporheic zones nitrate loss is of the order of 10%. More significant nitrate losses were observed in the dammed reaches and in a small reservoir in the upper part of the river. Results of the study have implications for identification of measures that can be undertaken to reduce nitrate export from the catchment. Because of the role of groundwater in river runoff reduction of nitrate loads to the aquifer should be primary objective. Acknowledgements. The work was carried out as part of the BONUS Soils2Sea project on groundwater system (http:/www.soils2sea.eu) financed by the European Commission 7 FP contract 226536 and the statutory funds of the AGH University of Science and Technology (project No.11.11.140.026 and 11.11.220.01).

  4. Reuse of fresh water sludge in cement making.

    PubMed

    Pan, R; Huang, C; Lin, S

    2004-01-01

    With the increasing demand for high quality water, a large quantity of chemical agent must be added in the water purification process, which in turn generates enormous amount of fresh water sludge. Of all the options for sludge disposal, sludge reuse has been considered most economical and environmentally sound. This study evaluated the possibility of incorporating fresh water sludge in the making of Portland cement through the sintering process. The goal was to search for the optimal condition to maximize the replacement of clay with the fresh water sludge. Characteristics of fresh water sludge were collected and analyzed. The analysis showed that water source and water treatment process dominate th characteristics, particularly the chemical composition of the fresh water sludge. The fresh water sludge was mixed with the cement clay in various percentages, from 0% to 100%, as raw material for cement-making. The effects of its addition on the sintering condition and the quality of cement were evaluated. The analysis of the clinkers showed that the addition of the fresh water sludge did not change the phase form and the f-CaO content of the cement. The compressive strength of the masonry increased with the increasing addition of fresh water sludge. All cement products made from various replacement ratios met the Chinese National Standard of first degree Portland cement.

  5. Modelling of water inflow to the Kolyma reservoir in historical and future climates

    NASA Astrophysics Data System (ADS)

    Lebedeva, Liudmila; Makarieva, Olga; Ushakov, Mikhail

    2017-04-01

    Kolyma hydropower plant is the most important electricity producer in the Magadan region, North of Russian Far East. North-Eastern Russia has sparse hydrometeorological network. The density is one hydrological gauge per 10 250 km2. Assessment of water inflow to the Kolyma reservoir is complicated by mountainous relief with altitudes more than 2000 m a.s.l., continuous permafrost and sparse data. The study aimed at application of process-based hydrological model to simulate water inflow to the Kolyma reservoir in historical time period and according to projections of future climate. Watershed area of the Kolyma reservoir is 61 500 km2. Dominant landscapes are mountainous tundra and larch forest. The Hydrograph model used in the study explicitly simulates heat and water dynamics in the soil profile thus is able to reflect ground thawing/freezing and change of soil storage capacity through the summer in permafrost environments. The key model parameters are vegetation and soil properties that relate to land surface classes. They are assessed based on field observations and literature data, don't need calibration and could be transferred to other basins with similar landscapes. Model time step is daily, meteorological input are air temperature, precipitation and air moisture. Parameter set that was firstly developed in the small research basins of the Kolyma water-balance station was transferred to middle and large river basins in the region. Precipitation dependences on altitude and air temperature inversions are accounted for in the modelling routine. Successful model application to six river basins with areas from 65 to 42600 km2 within the watershed of the Kolyma reservoir suggests that simulation results for the water inflow to the reservoir are satisfactory. Modelling according to projections of future climate change showed that air temperature increase will likely lead to earlier snowmelt and lower freshet peaks but doesn't change total inflow volume. The study

  6. Stability and forcing of the Iceland-Faroe inflow of water, heat, and salt to the Arctic

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Hátún, H.; Kristiansen, R.; Olsen, S. M.; Østerhus, S.

    2010-07-01

    The flow of Atlantic water across the Greenland-Scotland Ridge (Atlantic inflow) is critical for conditions in the Nordic Seas and Arctic Ocean by importing heat and salt. Here, we present a decade-long series of measurements from the Iceland-Faroe inflow branch (IF-inflow), which carries almost half the total Atlantic inflow. The observations show no significant trend in volume transport of Atlantic water, but temperature and salinity increased during the observational period. On shorter time scales, the observations show considerable variations but no statistically significant seasonal variation is observed and even weekly averaged transport values were consistently uni-directional from the Atlantic into the Nordic Seas. Combining transport time-series with sea level height from satellite altimetry and wind stress reveals that the force driving the IF-inflow across the topographic barrier of the Ridge is mainly generated by a pressure gradient that is due to a continuously maintained low sea level in the Southern Nordic Seas. This links the IF-inflow to the estuarine and thermohaline processes that generate outflow from the Nordic Seas and lower its sea level. The IF-inflow is an important component of the system coupling the Arctic region to the North Atlantic through the thermohaline circulation, which has been predicted to weaken in the 21st century. Our observations show no indication of weakening, as yet.

  7. Stability and forcing of the Iceland-Faroe inflow of water, heat, and salt to the Arctic

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Hátún, H.; Kristiansen, R.; Olsen, S. M.; Østerhus, S.

    2010-12-01

    The flow of Atlantic water across the Greenland-Scotland Ridge (Atlantic inflow) is critical for conditions in the Nordic Seas and Arctic Ocean by importing heat and salt. Here, we present a decade-long series of measurements from the Iceland-Faroe inflow branch (IF-inflow), which carries almost half the total Atlantic inflow. The observations show no significant trend in volume transport of Atlantic water, but temperature and salinity increased during the observational period. On shorter time scales, the observations show considerable variations but no statistically significant seasonal variation is observed and even weekly averaged transport values were consistently uni-directional from the Atlantic into the Nordic Seas. Combining transport time-series with sea level height from satellite altimetry and wind stress reveals that the force driving the IF-inflow across the topographic barrier of the Ridge is mainly generated by a pressure gradient that is due to a continuously maintained low sea level in the Southern Nordic Seas. This implies that the relative stability of the IF-inflow derives from the processes that lower the sea level by generating outflow from the Nordic Seas, especially the thermohaline processes that generate overflow. The IF-inflow is an important component of the system coupling the Arctic region to the North Atlantic through the thermohaline circulation, which has been predicted to weaken in the 21st century. Our observations show no indication of weakening.

  8. Water-quality characteristics of inflow to and outflow from Falls Lake, North Carolina, 1982-87

    USGS Publications Warehouse

    Garrett, R.G.

    1990-01-01

    Falls Lake, an 11,300-acre reservoir in the north-central Piedmont of North Carolina, was completed in December 1983. Hydrologic data were collected at seven inflow sites and one outflow site between 1982 and 1987 to define water-quality characteristics. Data include streamflow data and 56 physical and chemical characteristics of streamwater. Concentrations of some constituents at inflow sites were as much as 10-to 110-times greater than background concentrations in streams relatively unaffected by man. At the outflow site, these constituents generally were 2-to 3-times greater than background values. The minimum dissolved-oxygen concentration measured at an inflow site was 0.6 mg/L, whereas the minimum concentration measured at the outflow site was 6.7 milligrams per liter. Significant differences in other physical characteristics between inflow and outflow sites include a reduction in maximum concentration of suspended sediment from 1,850 milligrams per liter in an inflow sample to 100 milligrams per liter in an outflow sample, and a reduction of maximum specific-conductance values from more than 1,200 microsiemens/centimeter in an inflow sample to 140 microsiemens per centimeter in the outflow. The maximum concentration of total nitrogen at inflow sites was 33 milligrams per liter compared with 4.5 milligrams per liter at the outflow site. Similarly, the maximum total phosphorus concentration at inflow sites was 20 milligrams per liter, but 0.22 milligrams per liter at the outflow site. Average annual loads of nitrogen and phosphorus in the outflow were as much as 66 percent and 21 percent of inflow loads, respectively. Although maximum inflow yields were 13 tons per square mile for nitrogen and 2.8 tons per square mile for phosphorus, yields of these constituents at the outflow site were about 1.1 and 0.05 tons per square mile, respectively.

  9. Water-quality characteristics of inflow to and outflow from B Everett Jordan Lake, North Carolina, 1982-86

    USGS Publications Warehouse

    Garrett, R.G.

    1990-01-01

    B. Everett Jordan Lake, a 13,900-acre reservoir in the north-central Piedmont of North Carolina, was completed in February 1982. Hydrologic data were collected at four inflow sites and one outflow site to define water-quality characteristics. Data include streamflow data and 56 physical and chemical characteristics of streamwater. Concentrations of some constituents at inflow sites were as much as 83-times greater than background concentrations in streams relatively unaffected by man. At the outflow site, however, some of these constituents were only as much as 6-times greater. The minimum dissolved-oxygen concentration measured at an inflow site was 1.0 mg/L, whereas the minimum concentration measured at the outflow site was 4.9 mg/L. Significant differences in other physical characteristics between inflow and outflow sites include a reduction in maximum concentration of suspended sediment from 2,360 mg/L in an inflow sample to 130 mg/L at the outflow site and a reduction of maximum specific conductance values from more than 1,100 microsiemens/centimeter in an inflow sample to 301 microsiemens/centimeter in outflow. The maximum concentration of total nitrogen at inflow sites was 27.0 mg/L compared with 3.2 mg/L at the outflow site. The maximum total phosphorus concentration at inflow sites was 13.0 mg/L compared with 0.6 mg/L at the outflow site. Average annual loads of total nitrogen and total phosphorus in the outflow were as much as 67% and 40% of inflow loads, respectively. Maximum yields at an inflow site were 5.8 t/sq mi (tons per square mile) for nitrogen and 1.4 t/sq mi for phosphorus. Yields of these constituents at the outflow site were 1.5 and 0.2 t/mi, respectively.

  10. Benthic Foraminiferal Distribution in the Baltic Sea as Indicator of the North Atlantic Water Inflow

    NASA Astrophysics Data System (ADS)

    Ponomarenko, Ekaterina; Krechik, Viktor

    2017-04-01

    The Baltic Sea is a brackish water land-locked sea, with a strongly stratified water column and restricted exchange of bottom water. The hydrological regime of deep waters is strongly influenced by irregular inflows of high-saline Atlantic water through the Danish straits. For the present study 22 surface sediment samples were collected in the Russian sector of the Baltic Sea with sediment grab OCEAN during the 131st cruise of the R/V Professor Shtokman (March-April 2016). Water salinity was measured by Sea&Sun CTD 90M. Benthic foraminifera were counted and identified in the >63 μm size fraction. A total of 25 species were identified. Agglutinated species are the most abundant in the assemblages. They are represented by 18 species which belong to Saccammina sphaerica, Crithionina and Thurammina taxa. Genera of calcareous species Cribroelphidium and Melonis are extremely rare in the study area, except for the station showing the highest salinity value (Gdansk Basin) where these species are relatively abundant in the association. Single tests of planktonic foraminifera were also found at some stations. Distribution of benthic foraminifera demonstrates a clear correlation with salinity of the bottom waters and the topography of the region. Maximum foraminifera concentrations as well as increase in faunal diversity correspond to the deeper parts of the study region where saline North Atlantic water flowing via Stolpe Furrow is accumulated. In the Gdansk Basin, it is even possible to trace the direction of the saline water inflow by simultaneous decrease in salinity, as well as foraminiferal tests and species concentrations with increasing distance from the Stolpe Furrow.

  11. Temporal variability of the Circumpolar Deep Water inflow onto the Ross Sea continental shelf

    NASA Astrophysics Data System (ADS)

    Castagno, Pasquale; Falco, Pierpaolo; Dinniman, Michael S.; Spezie, Giancarlo; Budillon, Giorgio

    2017-02-01

    The intrusion of Circumpolar Deep Water (CDW) is the primary source of heat, salt and nutrients onto Antarctica's continental shelves and plays a major role in the shelf physical and biological processes. Different studies have analyzed the processes responsible for the transport of CDW across the Ross Sea shelf break, but until now, there are no continuous observations that investigate the timing of the intrusions. Also, few works have focused on the effect of the tides that control these intrusions. In the Ross Sea, the CDW intrudes onto the shelf in several locations, but mostly along the troughs. We use hydrographic observations and a mooring placed on the outer shelf in the middle of the Drygalski Trough in order to characterize the spatial and temporal variability of CDW inflow onto the shelf. Our data span from 2004 to the beginning of 2014. In the Drygalski Trough, the CDW enters as a 150 m thick layer between 250 and 400 m, and moves upward towards the south. At the mooring location, about 50 km from the shelf break, two main CDW cores can be observed: one on the east side of the trough spreading along the west slope of Mawson Bank from about 200 m to the bottom and the other one in the central-west side from 200 m to about 350 m depth. A signature of this lighter and relatively warm water is detected by the instruments on the mooring at bottom of the Drygalski Trough. High frequency periodic CDW intrusion at the bottom of the trough is related to the diurnal and spring/neap tidal cycles. At lower frequency, a seasonal variability of the CDW intrusion is noticed. A strong inflow of CDW is observed every year at the end of December, while the CDW inflow is at its seasonal minimum during the beginning of the austral fall. In addition an interannual variability is also evident. A change of the CDW intrusion before and after 2010 is observed.

  12. Estimating the glacial melt water contribution to the fresh water budget from salinity and δ18O measurements in Godthåbsfjord

    NASA Astrophysics Data System (ADS)

    Fitzner, Antje; van As, Dirk; Bendtsen, Jorgen; Dahl-Jensen, Dorthe; Fettweis, Xavier; Mortensen, John; Rysgaard, Soren

    2013-04-01

    The mass loss of the Greenland ice sheet increases due to changes in the surface mass balance and accelerated ice discharge through numerous outlet glaciers at the margins. The melt has global and local consequences. Globally the sea level rises and locally the increased fresh water inflow affects fishery and transportation. In this study we focus on the fjord system near Nuuk in West Greenland, Godthåbsfjord. Godthåbsfjord is a unique fjord with its length of about 300 km and a shallow sill at the fjord entrance that protects the fjord system. There are several tidewater glaciers terminating into the fjord and two land-terminating glaciers along the fjord contributing to the fresh water content in the fjord. The largest tidewater glacier is Kangiata Nunåta Sermia. The freshwater originates primarily from three processes: surface melt, ice berg calving and basal melt. Observations and climate models can give estimates for calving and surface melt. Basal melt, however, cannot be observed directly. Even though mass loss by basal melting is neglected on the global scale, it plays an important role in the small regional environment like fjords and the glaciers itself. Warmer ocean temperatures increase basal melt, and resulting lubrication accelerates tidewater glaciers. Overall, the freshwater content in the fjord increases. Salinity measurements taken in the fjord between 2007 and 2011 show a seasonal variability originating from the variation in fresh water inflow. Based on salinity records only, it is not possible to distinguish between the different fresh water sources like precipitation and melt. Hence, δ18O measurements are used in addition to salinity records to determine the origin of the fresh water because of the different δ18O signatures of run-off and glacial melt water. The resulting fresh water inflow and the glacial melt contribution are compared to independent estimates and regional climate model output.

  13. Real-time short-term forecast of water inflow into Bureyskaya reservoir

    NASA Astrophysics Data System (ADS)

    Motovilov, Yury

    2017-04-01

    During several recent years, a methodology for operational optimization in hydrosystems including forecasts of the hydrological situation has been developed on example of Burea reservoir. The forecasts accuracy improvement of the water inflow into the reservoir during planning of water and energy regime was one of the main goals for implemented research. Burea river is the second left largest Amur tributary after Zeya river with its 70.7 thousand square kilometers watershed and 723 km-long river course. A variety of natural conditions - from plains in the southern part to northern mountainous areas determine a significant spatio-temporal variability in runoff generation patterns and river regime. Bureyskaya hydropower plant (HPP) with watershed area 65.2 thousand square kilometers is a key station in the Russian Far Eastern energy system providing its reliable operation. With a spacious reservoir, Bureyskaya HPP makes a significant contribution to the protection of the Amur region from catastrophic floods. A physically-based distributed model of runoff generation based on the ECOMAG (ECOlogical Model for Applied Geophysics) hydrological modeling platform has been developed for the Burea River basin. The model describes processes of interception of rainfall/snowfall by the canopy, snow accumulation and melt, soil freezing and thawing, water infiltration into unfrozen and frozen soil, evapotranspiration, thermal and water regime of soil, overland, subsurface, ground and river flow. The governing model's equations are derived from integration of the basic hydro- and thermodynamics equations of water and heat vertical transfer in snowpack, frozen/unfrozen soil, horizontal water flow under and over catchment slopes, etc. The model setup for Bureya river basin included watershed and river network schematization with GIS module by DEM analysis, meteorological time-series preparation, model calibration and validation against historical observations. The results showed good

  14. Inflow, outflow, and water levels in Lake Michigan during the last part of the Wisconsin glaciation

    SciTech Connect

    Clayton, L.; Attig, J.W. ); Mickelson, D.M. . Dept. of Geology and Geophysics)

    1992-01-01

    Between about 14,000 and 10,000 B.P., water flowed to and from Lake Michigan through several channels connected with adjacent glacial lakes and the Mississippi basin. Inflow and outflow depend on lake-level fluctuations, but no known lake-level chronology for the Lake Michigan basin explains all the supposed facts. Several kinds of information can be use to construct such a chronology: elevations of beaches, elevations and locations of outlets, ice-margin positions, till stratigraphy, and glacial history relative to outlets and lake-sediment distribution. If the crustal rebound predicted by J.A. Clark (bracketed by glacial Lake Wisconsin and Door Peninsula water planes) is used as the basis for a lake-level chronology, lake elevations would have been much higher than previously recognized, beaches previously thought to be late glacial must be middle Holocene, and the predicted sequence of spillways from glacial Lake Oshkosh, in the Green Bay basin, to Lake Michigan seems incompatible with the till stratigraphy of the region. On the other hand, a hinge line model such as proposed by J.W. Goldthwait allows far less rebound than is required by their knowledge of present-day rebound and by the rebound interpreted from shore features of glacial Lake Wisconsin. Therefore major flaws exist in their understanding of the glacial chronology and stratigraphy, of the glacial lake deposits, or of the crustal rebound; the reconstructed of inflow and outflow will remain uncertain until these conflicts are resolved.

  15. The Iceland-Faroe inflow of Atlantic water to the Nordic Seas

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Osterhus, S.; Hatun, H.

    2003-04-01

    The flow of Atlantic water between Iceland and the Faroe Islands is one of three current branches flowing from the Atlantic into the Nordic Seas across the Greenland-Scotland Ridge. By the heat that it carries along, it keeps the subarctic regions abnormally warm and by its import of salt, it helps maintain a high salinity and hence density in the surface waters as a precondition for thermohaline ventilation. From 1997 to 2001, a number of ADCPs have been moored on a section going north from the Faroes, crossing the inflow. Combining these measurements with decade-long CTD observations from research vessel cruises along this section, we compute the fluxes of water (volume), heat, and salt. For the period June 1997 to June 2001, we found the average volume flux of Atlantic water to be 3.5 ± 0.5 Sv (1 Sv = 10^6 m^3 x s-1), which makes this the branch with the largest volume flux according to recent estimates. This water was found to carry a heat flux of 125 ± 15 TW (1 TW = 1012 W), referenced to 0oC and a salt flux of 125 ± 15 kilotonnes per second. The Iceland-Faroe Atlantic water volume flux was found to have a negligible seasonal variation. Budget estimates and simple models indicate that thermohaline ventilation in the Arctic Mediterranean can drive most of the Atlantic inflow to the Nordic Seas and for the Iceland-Faroe branch, at least, the stability of the observed flux verifies that this is indeed the dominant forcing mechanism.

  16. Estimated water and nutrient inflows and outflows, Lake Cochituate, eastern Massachusetts, 1977-79

    USGS Publications Warehouse

    Gay, F.B.

    1984-01-01

    Streamflow was the major source of water and nutrients (nitrogen and phosphorus) to Lake Cochituate, followed by ground water, and then precipitation during April 1978 through March 1979. Compared to all sources during that period, streams contributed 7,217 million gallons (a little over 82 percent) of water, 63 ,000 pounds (between 50 and 60 percent) of nitrogen, and 3,000 pounds (94 percent) of phosphorus. A little over 60 percent of all the water that entered Lake Cochituate flowed from Fisk Pond. This single source transported about 38,000 pounds of nitrogen and 2,000 pounds of phosphorus. Ground-water inflow to Lake Cochituate occurs along its shoreline except at the north end of Lake Cochituate 's North Pond where natural seepage from the lake is occurring and at locations on the lake 's Middle and South Ponds where municipal wells induce infiltration of lake water amounting to 1,228 million gallons for that period. Discharge of ground water to the lake was estimated to range from 462 to 816 million gallons and transported from 31,000 to 55,000 pounds of nitrogen and from 46 to 82 pounds of phosphorus. Bulk precipitation was estimated to contribute about the same volume of water to the lake as ground water but double its phosphorus load. However, the load of nitrogen, 8000 pounds, from bulk precipitation was the smallest of any source. (USGS)

  17. Simulation of salt water-fresh water interface motion

    SciTech Connect

    Ferrer Polo, J.; Ramos, F.J.

    1983-02-01

    A mathematic model is presented which describes the salt water-fresh water motion with a sharp interface, assuming the validity of the Dupuit approximation. This model is used as a base to derive a numeric-model (finite difference method) which is unconditionally convergent and stable. A method for solving the equations is selected together with a convergence accelerating procedure. The treatment of the boundary conditions in the interface is discussed, and a general and automatic solution for that problem is presented. Several tests with analytic solutions have been performed with good results. 13 references.

  18. Temporal variability of the Circumpolar Deep Water inflow onto the Ross Sea continental shelf

    NASA Astrophysics Data System (ADS)

    Falco, P.; Castagno, P.; Budillon, G.; Spezie, G.

    2016-02-01

    The Circumpolar Deep Water (CDW) intrusion on the Antarctic continental shelves is the primary source of heat, salt and nutrients playing a major role on the shelf physical and biological processes. Different studies have analyzed the processes responsible for the transport of CDW across the Ross Sea shelf break, but until now, there are no continuous observations that investigate the time of the intrusions. Besides, few works focused on the effect of the tide that controls the intrusion itself. In the Ross Sea, the CDW intrudes onto the shelf in several locations mostly along the troughs, such as the Glomar Challenger, the Joides and the Drygalski. We use hydrographic observations and three moorings placed (one) on the outer shelf in the middle of the Drygalski Trough and (two) on the upper slope at the mouth of the Glomar Challenger basin, in order to characterize the spatial and temporal variability of the CDW inflow onto the shelf. Our data span from 2004 to 2014. In the Drygalski Trough the CDW enters as a thick layer of about 150 m between 250 - 400 m moving upward toward south. At the mooring location, about 50 Km from the shelf break, two main CDW cores can be observed: one on east side of the trough spreading along the west slope of Mawson Bank from about 200 m to the bottom and the other one in the central-west side from 200 m to about 350 m. A signature of this lighter and relatively warm water is detected by the instruments on the mooring at bottom of the Drygalski Trough. The CDW intrusion at the bottom of the trough is strictly related to the diurnal and spring/neap tidal cycles, but a strong seasonal variability of the CDW is clear. A strong inflow of CDW is observed every year at the end of December (after few months that the salinity minimum is registered), while the CDW inflow is at its seasonal minimum during the end of the austral summer in correspondence of the salinity maximum associated with the High Salinity Shelf Water (HSSW). Indeed, the

  19. Melting icebergs to produce fresh water and mechanical energy

    SciTech Connect

    Camirand, W.M.; Hautala, E.; Randall, J.M.

    1981-10-20

    Fresh water and mechanical energy are obtained from melting of icebergs. Warm surface seawater is contacted with a fluid, which is vaporized. The resulting vapor is used to generate mechanical energy and then is condensed by contacting it with cold melt water from the iceberg. The fluid is regenerated with a concomitant elevation in the temperature of the melt water. The warmer melt water is cycled to the body of the iceberg to facilitate its melting and produce additional cold melt water, which is apportioned as fresh water and water cycled to condense the aforesaid vapor. In an alternate embodiment of the invention warm seawater is evaporated at reduced pressure. Mechanical energy is generated from the vapor, which is then condensed by direct and intimate contact with cold melt water from the iceberg. The resultant fresh water is a mixture of condensed vapor and melt water from the iceberg and has a temperature greater than the cold melt water. This fresh water mixture is contacted with the body of the iceberg to further melt it; part of the cold melt water is separated as fresh water and the remainder is cycled for use in condensing the vapor from the warm surface seawater.

  20. Natural recharge and localization of fresh ground water in Kuwait

    USGS Publications Warehouse

    Bergstrom, R.E.; Aten, R.E.

    1965-01-01

    Fresh ground water (200 parts per million total dissolved solids and upwards) occurs in portions of Pleistocene sandstone aquifers beneath basins and wadis in north Kuwait where the mean rainfall is about five inches per year. The fresh water is surrounded and underlain by brackish water (> 4000 ppm TDS). Drilling and testing show that fresh water saturation is restricted to wadis and basin areas; in Rawdatain basin it attains a maximum thickness of about 110 feet and a lateral extent of about seven miles. The fresh ground water represents recharge localized, during infrequent, torrential rain storms, in areas of concentrated runoff where sediments in the vadose zone are moderately permeable and depth to the water table is generally less than a hundred feet. Concentration of runoff appears to be the primary control in the localization of recharge. The fresh water percolates downward to the ground-water reservoir following rare storms, then flows in the direction of hydraulic gradient and gradually becomes brackish. Theoretical delineation of the recharge area and ground-water flow pattern in Rawdatain was confirmed by tritium and C14 dating of the water. Brackish ground-water conditions prevail from water table downward in areas where rainfall infiltrates essentially where it falls, permeability of sediments in the vadose zone is low, or the water table is several hundred feet below land surface. In these areas, rainfall is retained and lost within the soil zone or becomes mineralized during deep percolation. ?? 1964.

  1. Toward an Improved Understanding of the Global Fresh Water Budget

    NASA Technical Reports Server (NTRS)

    Hildebrand, Peter H.

    2005-01-01

    The major components of the global fresh water cycle include the evaporation from the land and ocean surfaces, precipitation onto the Ocean and land surfaces, the net atmospheric transport of water from oceanic areas over land, and the return flow of water from the land back into the ocean. The additional components of oceanic water transport are few, principally, the mixing of fresh water through the oceanic boundary layer, transport by ocean currents, and sea ice processes. On land the situation is considerably more complex, and includes the deposition of rain and snow on land; water flow in runoff; infiltration of water into the soil and groundwater; storage of water in soil, lakes and streams, and groundwater; polar and glacial ice; and use of water in vegetation and human activities. Knowledge of the key terms in the fresh water flux budget is poor. Some components of the budget, e.g. precipitation, runoff, storage, are measured with variable accuracy across the globe. We are just now obtaining precise measurements of the major components of global fresh water storage in global ice and ground water. The easily accessible fresh water sources in rivers, lakes and snow runoff are only adequately measured in the more affluent portions of the world. presents proposals are suggesting methods of making global measurements of these quantities from space. At the same time, knowledge of the global fresh water resources under the effects of climate change is of increasing importance and the human population grows. This paper provides an overview of the state of knowledge of the global fresh water budget, evaluating the accuracy of various global water budget measuring and modeling techniques. We review the measurement capabilities of satellite instruments as compared with field validation studies and modeling approaches. Based on these analyses, and on the goal of improved knowledge of the global fresh water budget under the effects of climate change, we suggest

  2. Investigation of potential water inflow into a ventilated tunnel of the proposed low/intermediate-level waste repository in Switzerland

    SciTech Connect

    Eugster, S.M.; Senger, R.K.

    1995-03-01

    Design calculations of two-phase flow phenomena associated with the construction and ventilation of a tunnel were investigated to estimate the potential water inflow through discrete water-conducting features (WCFs) into the tunnel. The physical processes that were considered in numerical simulations include the transient propagation of the pressure decline into the formation (Valanginian Marl, initially fully saturated, no dissolved gas) as a result of the tunnel construction. Ventilation of the tunnel results in a reduction in relative humidity of the tunnel air which, in turn, causes evaporation of water at the tunnel wall and the potential development of an unsaturated zone into the formation. The objective of this study is to investigate under what conditions the tunnel wall appears wet or dry, i.e. whether WCFs can be identified in a ventilated tunnel by mapping water inflow patterns. The simulation results indicate that inflow to the tunnel decreases with time approaching steady state flow rates under single-phase flow conditions, which is lower than the evaporation rate. The water inflow rate decreased more rapidly for a first model scenario (WCF parallel to the tunnel axis), caused by linear flow through the WCF, than for a second model scenario (WCF perpendicular to the tunnel axis), characterized by radial flow toward the tunnel. Similarly, the desaturation zone extends farther into the WCF under linear flow than under radial flow.

  3. Robustness Analysis of Regional Water Supply Portfolios using Synthetic Inflow Scenarios with Variable Drought Frequency

    NASA Astrophysics Data System (ADS)

    Herman, J. D.; Zeff, H. B.; Lamontagne, J. R.; Reed, P. M.; Characklis, G. W.

    2015-12-01

    Robustness analyses of water supply systems have moved toward exploratory simulation to discover scenarios in which existing or planned policies may fail to meet stakeholder objectives. Such assessments rely heavily on the choice of plausible future scenarios, which, in the case of drought management, requires sampling or generating a broad ensemble of reservoir inflows which do not necessarily reflect the historical record. Here we adapt a widely used synthetic streamflow generation method to adjust the frequency of low-flow periods, which can be related to impactful historical events from the perspective of decision makers. Specifically, the modified generation procedure allows the user to specify parameters n, p such that events with observed weekly non-exceedance frequency p appear in the synthetic scenario with approximate frequency np (i.e., the pth percentile flow occurs n times more frequently). Additionally, the generator preserves the historical autocorrelation of streamflow and its seasonality, as well as approximate multi-site correlation. Using model simulations from recent work in multi-objective urban drought portfolio planning in North Carolina, a region whose water supply faces both climate and population pressures, we illustrate the decision-relevant consequences caused by raising the frequency of low flows associated with the 2007-2008 drought. This method explores system performance under extreme events of increasing frequency prior to reconciling these findings with climate model projections, and thus can be used to support bottom-up robustness methods in water systems planning.

  4. Land use, water use, streamflow characteristics, and water-quality characteristics of the Charlotte Harbor inflow area, Florida

    USGS Publications Warehouse

    Hammett, K.M.

    1990-01-01

    Charlotte Harbor is a 270-square-mile estuarine system in west-central Florida. It is being subjected to increasing environmental stress by rapid population growth and development. By 2020, population in the inflow area may double, which will result in increased demands for freshwater and increased waste loads. The Charlotte Harbor inflow area includes about 4,685 square miles. The Myakka, the Peace, and the Caloosahatchee are the major rivers emptying into the harbor. About 70 percent of the land in these three river basins is used for agriculture and range. In the coastal basin around Charlotte Harbor, about 50 percent of the total land area is devoted to commercial or residential uses. Water use in the inflow area is about 565 million gallons per day, of which 59 percent is used for irrigation, 26 percent for industry, 11 percent for public supply, and 4 percent for rural supply. Total freshwater inflow from the three major rivers, the coastal area, and rainfall directly into Charlotte Harbor averages between 5,700 and 6,100 cubic feet per second, which is more than 3,500 million gallons per day. A trend analysis of about 50 years of streamflow data shows a statistically significant decreasing trend for the Peace River stations at Bartow, Zolfo Springs, and Arcadia. No significant trend has been observed in the Myakka or the Caloosahatchee River data. In the Peace River, the decrease in flow may be related to a long-term decline in the potentiometric surface of the underlying Floridan aquifer system, which resulted from ground-water withdrawals. It is not possible to determine whether the trend will continue. However, if it does continue at the same rate, then, except for brief periods of storm runoff, the Peace River at Zolfo Springs could be dry year-round in about 100 years. Of the 114 facilities permitted to discharge domestic or industrial effluent to waters tributary to Charlotte Harbor, 88 are in the Peace River basin. Phosphate ore and citrus processing

  5. A High-Resolution Record of Warm Water Inflow and Iceberg Calving in Upernavik Isfjord During the Past 150 Years.

    NASA Astrophysics Data System (ADS)

    Vermassen, F.; Andresen, C. S.; Sabine, S.; Holtvoeth, J.; Cordua, A. E.; Wangner, D. J.; Dyke, L. M.; Kjaer, K. H.; Kokfelt, U.; Haubner, K.

    2016-12-01

    There is a growing body of evidence demonstrating that changes in warm water inflow to Greenlandic fjords are linked to the rapid retreat of marine-terminating outlet glaciers. This process is thought to be responsible for a substantial component of the increased mass loss from the Greenland Ice Sheet over the last two decades. Sediment cores from glaciated fjords provide high-resolution sedimentological and biological proxy records which can be used to evaluate the interplay of warm water inflow and glacier calving over recent time scales. In this study, multiple short cores ( 2 m) from Upernavik Isfjord, West Greenland, were analysed to establish a multi-proxy record of glacier behaviour and oceanographic conditions that spans the past 150 years. The down-core variation in the amount of ice-rafted debris reveals periods of increased glacier calving, and biomarker proxies are used to reconstruct variability in the inflow of warm, Atlantic-sourced water to the fjord. Measurements of the sortable silt grain size are used to reconstruct bottom-current strength; periods of vigorous current flow are assumed to be due to enhanced warm water inflow. Finally, a record of glacier terminus position changes, derived from historical observations and satellite imagery, allows comparison of our new proxy records with the retreat of the ice margin from 1849 onwards. We use these data to assess the relative importance of mechanisms controlling the (rapid) retreat of marine-terminating glaciers in Upernavik Isfjord.

  6. High terrestrial carbon load via groundwater to a boreal lake dominated by surface water inflow

    NASA Astrophysics Data System (ADS)

    Einarsdottir, Karolina; Wallin, Marcus B.; Sobek, Sebastian

    2017-01-01

    The input of dissolved organic and inorganic carbon (DOC and DIC) via direct groundwater seepage to boreal lakes is often assumed to be small in noncarbonaceous areas. However, measurements are rare. We estimated the terrestrial load of DOC, DIC, and methane (CH4) to a small boreal lake for the open water period, on the basis of measured concentrations of carbon species in near-shore groundwater wells and inlet streams, and measured area-specific discharge. The subcatchment directly draining into the lake via groundwater seepage contributed 18% to the total water input during the open water season. Compared to stream and lake water, near-shore groundwater concentrations of DOC were slightly elevated, and groundwater DIC and CH4 concentrations were highly elevated. Consequently, direct groundwater seepage contributed 27% to the total DOC load, 64% to the total DIC load, and 96% to the total CH4 load from the catchment to the lake. Groundwater DIC import corresponded only to 5-8% of lake carbon dioxide (CO2) emission. In incubation experiments, we observed higher photochemical DOC loss rates in stream and groundwater samples (18-55% DOC loss upon 72 h UV-A exposure) than in lake water (15% DOC loss) and detected significant DOC flocculation in groundwater samples in both light and dark incubations (2-24% DOC loss). We conclude that even in regions where lake hydrology is dominated by surface water inflow via inlet streams, direct groundwater seepage can represent an important carbon source to boreal lakes, and groundwater DOC may be susceptible to in-lake removal via degradation and flocculation.

  7. Accumulation of enteric bacteriophage in fresh water sediments.

    PubMed

    Skraber, Sylvain; Schijven, Jack; Italiaander, Ronald; de Roda Husman, Ana Maria

    2009-09-01

    Our study aimed to assess the accumulation of bacteriophages in sandy and clayey fresh water sediments. All of the 24 natural fresh water sediments were positive for somatic and F-specific phages, though their concentrations in the overlying water were undetectable in 1 and 11 samples, respectively, out of 24, corresponding to 4 and 46% for somatic and F-specific phages, respectively. Based on the sediment-to-water ratios, F-specific phages accumulate over 100 times more than the somatic coliphages in clayey sediments. Inactivation of bacteriophages in clayey and sandy sediments over a 1-month period at 15 degrees C was negligible. Our data suggest that persistence of deposited viruses in fresh water sediments leads to accumulation and the findings call for additional investigations on the fate of entrapped pathogenic viruses.

  8. Lateral inflows, stream-groundwater exchange, and network geometry influence stream water composition

    NASA Astrophysics Data System (ADS)

    Mallard, John; McGlynn, Brian; Covino, Tim

    2014-06-01

    The role of stream networks and their hydrologic interaction with hillslopes and shallow groundwater in modifying and transporting watershed signals is an area of active research. One of the primary ways that stream networks can modify watershed signals is through spatially variable stream gains and losses, described herein as hydrologic turnover. We measured hydrologic gain and loss at the reach scale using tracer experiments throughout the Bull Trout watershed in the Sawtooth Mountains of Idaho. We extended the results of reach scale experiments to the stream network using empirical relationships between (1) watershed area and stream discharge and (2) stream discharge and percent stream water loss to the groundwater system. We thus incorporate linkages between (1) hillslopes and stream networks via lateral inflows and (2) stream networks and shallow groundwater via hydrologic exchange. We implemented these relationships within a concise analytical framework to simulate hydrologic turnover across stream networks and estimate the variable influence exerted by upstream reaches and streamflow source locations on stream water composition across stream networks. Application to six natural Sawtooth watersheds and seven synthetic watersheds with varying topographic structure and stream network geometry indicated that contributions to discharge from any upstream source depend on the magnitude of the initial input, but also on the distribution of hydrologic turnover occurring along the stream network. The evolution of stream water source compositions along stream networks was unique in each watershed due to the combination of watershed structure and stream network geometry. Our results suggest that a distributed representation of hydrologic turnover at the stream network scale can improve understanding of how the stream network can modify source water compositions along the stream.

  9. Saline solutions: the quest for fresh water.

    PubMed Central

    Reuther, C G

    2000-01-01

    Despite steady advances in the technology, desalination remains one of the most expensive ways to produce potable water. But as water scarcity forces communities to find new sources of drinking water, scientists are developing innovations that may soon make desalination a reasonable option for many more communities. The newest approach to desalination is membrane systems, which include reverse osmosis and electrodialysis systems. Current research seeks to make these systems more effective and less likely to produce environmentally hazardous by-products. Many facilities use traditional distillation to desalinate water, and efforts are being made to combine membranes and distillation for more efficient systems. PMID:10656867

  10. Saline solutions: the quest for fresh water.

    PubMed

    Reuther, C G

    2000-02-01

    Despite steady advances in the technology, desalination remains one of the most expensive ways to produce potable water. But as water scarcity forces communities to find new sources of drinking water, scientists are developing innovations that may soon make desalination a reasonable option for many more communities. The newest approach to desalination is membrane systems, which include reverse osmosis and electrodialysis systems. Current research seeks to make these systems more effective and less likely to produce environmentally hazardous by-products. Many facilities use traditional distillation to desalinate water, and efforts are being made to combine membranes and distillation for more efficient systems.

  11. Human alterations of Earth's fresh water

    Treesearch

    Sandra Postel

    2000-01-01

    One of the biggest challenges society faces in this new century is figuring out how to satisfy the water demands of 8 billion people while at the same time protecting the aquatic ecosystems and ecological services that humans and all species depend upon. Since 1950, water demands worldwide have more than tripled, while the scale of our dams and reservoirs, river...

  12. A combined heat and water budget approach to quantify the groundwater inflow to a meromictic lake

    NASA Astrophysics Data System (ADS)

    Kettle, A.; Back, R.

    2012-04-01

    Groundwater exchange may have an important role in the mixing dynamics of certain lakes, in addition to the recognized effect of seasonally varying surface heat fluxes. However, the heat and mass fluxes associated with groundwater input to a lake are often difficult to measure and are poorly constrained. Permanent bottom anoxia in meromictic lakes is sometimes associated with significant inputs of surface water, which create a permanent upwelling system for phytoplankton blooms. In this contribution, we report the results of a 17 month experimental investigation of the heat and water budget of a meromictic lake in upstate New York. Fayetteville Green Lake is a good model system to conduct a combined heat and water budget analysis, with one outflow stream and a single inflow stream. The lake is contained in a relatively deep (~50m) flat-bottomed basin with a groundwater injection depth at ~20m at the base of the mixolimnion. The heat budget was formulated from data from regional meteorological stations and a vertical array of temperature sensors on a subsurface mooring. The mass budget was created from continuous measurements of lake stage and precipitation data. The results highlight that groundwater input has an important effect on the overall heat budget of the lake, with a critical role on the timing of the overturning of the mixolimnion in the spring and late autumn. Although lake heat budget studies have formerly been conducted to constrain the poorly-constrained evaporative term (latent heat) in the heat budget, our results suggest that groundwater exchange may dominate the surface latent heat flux of certain lakes.

  13. A combined heat and water budget approach to quantify the groundwater inflow to a meromictic lake

    NASA Astrophysics Data System (ADS)

    Kettle, Anthony; Back, Richard

    2013-04-01

    Groundwater exchange may have an important role in the mixing dynamics of certain lakes, and this may be comparable with near-surface mixing due to conventionally-defined surface radiation and turbulent heat fluxes. However, the heat and mass fluxes associated with groundwater input to a lake are often difficult to measure and are poorly constrained. Permanent bottom anoxia in meromictic lakes is sometimes associated with significant inputs of subsurface water, which creates a permanent upwelling system for phytoplankton blooms. This contribution presents the results of a 17 month experimental investigation of the heat and water budget of a meromictic lake in upstate New York. Fayetteville Green Lake is a good model system to conduct a combined heat and water budget analysis. It is a comparatively simple mass exchange system with one outflow stream and one significant inflow stream in addition to an important subsurface groundwater source. The lake is contained in a relatively deep (~50m) flat-bottomed basin with a groundwater injection depth at ~20m at the base of the mixolimnion. The heat budget was formulated from data from regional meteorological stations and a vertical array of temperature sensors on a subsurface mooring. The mass budget was created from continuous measurements of lake stage and precipitation data. The results highlight that groundwater input has an important effect on the overall heat budget of the lake, with an important role on the timing of the overturning of the mixolimnion in the spring and late autumn. Although lake heat budget studies have formerly been conducted to constrain the poorly-constrained evaporative term (latent heat) in the surface heat budget, the results of this study suggest that groundwater exchange may more important than the surface latent heat flux of certain lakes.

  14. Recovering fresh water stored in saline limestone aquifers.

    USGS Publications Warehouse

    Merritt, M.L.

    1986-01-01

    Numerical modeling techniques are used to examine the hydrogeologic, design, and management factors governing the recovery efficiency of subsurface fresh-water storage. The modeling approach permitted many combinations of conditions to be studied. A sensitivity analysis was used that consisted of varying certain parameters while keeping constant as many other parameters or processes as possible. The results show that a loss of recovery efficiency resulted from: 1) processes causing mixing of injected fresh water with native saline water (hydrodynamic dispersion); 2) processes or conditions causing the irreversible displacement of the injected fresh water with respect to the well (buoyancy stratification and background hydraulic gradients); or 3) processes or procedures causing injection and withdrawal flow patterns to be dissimilar (dissimilar injection and withdrawal schedules in multiple-well systems). Other results indicated that recovery efficiency improved considerably during the first several successive cycles, provided that each recovery phase ended whgen the chloride concentration of withdrawn water exceeded established criteria for potability (usually 250 milligrams per liter). Other findings were that fresh water injected into highly permeable or highly saline aquifers would buoy rapidly with a deleterious effect on recovery efficiency. -Author

  15. Fog as a fresh-water resource: overview and perspectives.

    PubMed

    Klemm, Otto; Schemenauer, Robert S; Lummerich, Anne; Cereceda, Pilar; Marzol, Victoria; Corell, David; van Heerden, Johan; Reinhard, Dirk; Gherezghiher, Tseggai; Olivier, Jana; Osses, Pablo; Sarsour, Jamal; Frost, Ernst; Estrela, María J; Valiente, José A; Fessehaye, Gebregiorgis Mussie

    2012-05-01

    The collection of fog water is a simple and sustainable technology to obtain fresh water for afforestation, gardening, and as a drinking water source for human and animal consumption. In regions where fresh water is sparse and fog frequently occurs, it is feasible to set up a passive mesh system for fog water collection. The mesh is directly exposed to the atmosphere, and the foggy air is pushed through the mesh by the wind. Fog droplets are deposited on the mesh, combine to form larger droplets, and run down passing into a storage tank. Fog water collection rates vary dramatically from site to site but yearly averages from 3 to 10 l m(-2) of mesh per day are typical of operational projects. The scope of this article is to review fog collection projects worldwide, to analyze factors of success, and to evaluate the prospects of this technology.

  16. Fresh water and power from the sea

    NASA Astrophysics Data System (ADS)

    Thomas, Anthony; Hillis, David L.

    An experiment--the Heat and Mass Transfer Scoping Test Apparatus--was built to obtain design data for a larger test that will assess the technical feasibility of the open-cycle OTEC process. (This closed-cycle concept was successfully demonstrated in 1979.) The project is a joint effort between Argonne National Laboratory (ANL) and the Solar Energy Research Institute (SERI). The apparatus was erected at the Natural Energy Laboratory of Hawaii and became operational in the summer of 1987. It is used by both ANL and SERI to conduct open-cycle OTEC experiments. After initial debugging, it produced 350 gallons per hour of potable water having a salinity of 86 ppM, one-fifth that of local tap water available at the test site.

  17. Innovative Fresh Water Production Process for Fossil Fuel Plants

    SciTech Connect

    James F. Klausner; Renwei Mei; Yi Li; Jessica Knight; Venugopal Jogi

    2005-09-01

    This project concerns a diffusion driven desalination (DDD) process where warm water is evaporated into a low humidity air stream, and the vapor is condensed out to produce distilled water. Although the process has a low fresh water to feed water conversion efficiency, it has been demonstrated that this process can potentially produce low cost distilled water when driven by low grade waste heat. This report describes the annual progress made in the development and analysis of a Diffusion Driven Desalination (DDD) system. A dynamic analysis of heat and mass transfer demonstrates that the DDD process can yield a fresh water production of 1.03 million gallon/day by utilizing waste heat from a 100 MW steam power plant based on a condensing steam pressure of only 3 Hg. The optimum operating condition for the DDD process with a high temperature of 50 C and sink temperature of 25 C has an air mass flux of 1.5 kg/m{sup 2}-s, air to feed water mass flow ratio of 1 in the diffusion tower, and a fresh water to air mass flow ratio of 2 in the condenser. Operating at these conditions yields a fresh water production efficiency (m{sub fW}/m{sub L}) of 0.031 and electric energy consumption rate of 0.0023 kW-hr/kg{sub fW}. Throughout the past year, the main focus of the desalination process has been on the direct contact condenser. Detailed heat and mass transfer analyses required to size and analyze these heat and mass transfer devices are described. The analyses agree quite well with the current data. Recently, it has been recognized that the fresh water production efficiency can be significantly enhanced with air heating. This type of configuration is well suited for power plants utilizing air-cooled condensers. The experimental DDD facility has been modified with an air heating section, and temperature and humidity data have been collected over a range of flow and thermal conditions. It has been experimentally observed that the fresh water production rate is enhanced when air

  18. Low toxic corrosion inhibitors for aluminum in fresh water

    NASA Technical Reports Server (NTRS)

    Humphries, T. S.

    1978-01-01

    Combinations of chemical compounds that reportedly reduce the corrosion of aluminum in fresh water were evaluated. These included combinations of borates, nitrates, nitrites, phosphates, silicates, and mercaptobenzothiazole. Eight of fifty inhibitor combinations evaluated gave excellent corrosion protection and compared favorably with sodium chromate, which has generally been considered standard for many years.

  19. Stable isotope estimates of evaporation: inflow and water residence time for lakes across the United States as a tool for national lake water quality assessments

    EPA Science Inventory

    Stable isotope ratios of water (delta18O and delta2H) can be very useful in large-scale monitoring programs because water samples are easy to collect and isotope ratios integrate information about basic hydrologic processes such as evaporation as a percentage of inflow (E/I) and ...

  20. Stable isotope estimates of evaporation: inflow and water residence time for lakes across the United States as a tool for national lake water quality assessments

    EPA Science Inventory

    Stable isotope ratios of water (delta18O and delta2H) can be very useful in large-scale monitoring programs because water samples are easy to collect and isotope ratios integrate information about basic hydrologic processes such as evaporation as a percentage of inflow (E/I) and ...

  1. [Fresh water macroinvertebrates of Costa Rica I].

    PubMed

    Springer, Monika; Ramirez, Alonso; Hanson, Paul

    2010-12-01

    This is the first in a series of three volumes on the freshwater macroinvertebrates of Costa Rica. The present volume includes an introductory chapter summarizing the major types of freshwater environments, the biology of freshwater macroinvertebrates (habitats, food, respiration, osmoregulation, etc.), ecological and economic importance, conservation and a synopis of the major groups, followed by a simplified key. The next two chapters discuss collecting methods and biomonitoring. These are followed by chapters on mayflies (Ephemeroptera: 10 families), dragonflies (Odonata: 13 families), stoneflies (Plecoptera: 1 family) and caddisflies (Trichoptera: 15 families). Both in this volume and in those to follow, the chapters treating individual taxa include a summary of the natural history, importance, taxonomy, collecting methods, morphology and an illustrated key to the families; each family is discussed separately and an illustrated key to genera is provided; each chapter ends with a bibliography and a table listing all the genera with information on number of species, distribution, habitat and tolerance to water pollution. While the emphasis is on families and genera known from Costa Rica, additional taxa occurring elsewhere in Central America are mentioned. The present volume also includes numerous color plates of aquatic macroinvertebrates.

  2. Increased salinization of fresh water in the northeastern United States

    PubMed Central

    Kaushal, Sujay S.; Groffman, Peter M.; Likens, Gene E.; Belt, Kenneth T.; Stack, William P.; Kelly, Victoria R.; Band, Lawrence E.; Fisher, Gary T.

    2005-01-01

    Chloride concentrations are increasing at a rate that threatens the availability of fresh water in the northeastern United States. Increases in roadways and deicer use are now salinizing fresh waters, degrading habitat for aquatic organisms, and impacting large supplies of drinking water for humans throughout the region. We observed chloride concentrations of up to 25% of the concentration of seawater in streams of Maryland, New York, and New Hampshire during winters, and chloride concentrations remaining up to 100 times greater than unimpacted forest streams during summers. Mean annual chloride concentration increased as a function of impervious surface and exceeded tolerance for freshwater life in suburban and urban watersheds. Our analysis shows that if salinity were to continue to increase at its present rate due to changes in impervious surface coverage and current management practices, many surface waters in the northeastern United States would not be potable for human consumption and would become toxic to freshwater life within the next century. PMID:16157871

  3. Increased salinization of fresh water in the northeastern United States.

    PubMed

    Kaushal, Sujay S; Groffman, Peter M; Likens, Gene E; Belt, Kenneth T; Stack, William P; Kelly, Victoria R; Band, Lawrence E; Fisher, Gary T

    2005-09-20

    Chloride concentrations are increasing at a rate that threatens the availability of fresh water in the northeastern United States. Increases in roadways and deicer use are now salinizing fresh waters, degrading habitat for aquatic organisms, and impacting large supplies of drinking water for humans throughout the region. We observed chloride concentrations of up to 25% of the concentration of seawater in streams of Maryland, New York, and New Hampshire during winters, and chloride concentrations remaining up to 100 times greater than unimpacted forest streams during summers. Mean annual chloride concentration increased as a function of impervious surface and exceeded tolerance for freshwater life in suburban and urban watersheds. Our analysis shows that if salinity were to continue to increase at its present rate due to changes in impervious surface coverage and current management practices, many surface waters in the northeastern United States would not be potable for human consumption and would become toxic to freshwater life within the next century.

  4. INNOVATIVE FRESH WATER PRODUCTION PROCESS FOR FOSSIL FUEL PLANTS

    SciTech Connect

    James F. Klausner; Renwei Mei; Yi Li; Mohamed Darwish; Diego Acevedo; Jessica Knight

    2003-09-01

    This report describes the annual progress made in the development and analysis of a Diffusion Driven Desalination (DDD) system, which is powered by the waste heat from low pressure condensing steam in power plants. The desalination is driven by water vapor saturating dry air flowing through a diffusion tower. Liquid water is condensed out of the air/vapor mixture in a direct contact condenser. A thermodynamic analysis demonstrates that the DDD process can yield a fresh water production efficiency of 4.5% based on a feed water inlet temperature of only 50 C. An example is discussed in which the DDD process utilizes waste heat from a 100 MW steam power plant to produce 1.51 million gallons of fresh water per day. The main focus of the initial development of the desalination process has been on the diffusion tower. A detailed mathematical model for the diffusion tower has been described, and its numerical implementation has been used to characterize its performance and provide guidance for design. The analysis has been used to design a laboratory scale diffusion tower, which has been thoroughly instrumented to allow detailed measurements of heat and mass transfer coefficient, as well as fresh water production efficiency. The experimental facility has been described in detail.

  5. INNOVATIVE FRESH WATER PRODUCTION PROCESS FOR FOSSIL FUEL PLANTS

    SciTech Connect

    James F. Klausner; Renwei Mei; Yi Li; Jessica Knight

    2004-09-01

    An innovative Diffusion Driven Desalination (DDD) process was recently described where evaporation of mineralized water is driven by diffusion within a packed bed. The energy source to drive the process is derived from low pressure condensing steam within the main condenser of a steam power generating plant. Since waste heat is used to drive the process, the main cost of fresh water production is attributed to the energy cost of pumping air and water through the packed bed. This report describes the annual progress made in the development and analysis of a Diffusion Driven Desalination (DDD) system. A combined thermodynamic and dynamic analysis demonstrates that the DDD process can yield a fresh water production of 1.03 million gallon/day by utilizing waste heat from a 100 MW steam power plant based on a condensing steam pressure of only 3'' Hg. Throughout the past year, the main focus of the desalination process has been on the diffusion tower and direct contact condenser. Detailed heat and mass transfer analyses required to size and analyze these heat and mass transfer devices are described. An experimental DDD facility has been fabricated, and temperature and humidity data have been collected over a range of flow and thermal conditions. The analyses agree quite well with the current data and the information available in the literature. Direct contact condensers with and without packing have been investigated. It has been experimentally observed that the fresh water production rate is significantly enhanced when packing is added to the direct contact condensers.

  6. Modeling the Influence of Variable Tributary Inflow on Circulation and Contaminant Transport in a Water Supply Reservoir

    NASA Astrophysics Data System (ADS)

    Nguyen, L. H.; Wildman, R.

    2012-12-01

    This study characterizes quantitatively the flow and mixing regimes of a water supply reservoir, while also conducting numerical tracer experiments on different operation scenarios. We investigate the effects of weather events on water quality via storm water inflows. Our study site the Kensico Reservoir, New York, the penultimate reservoir of New York City's water supply, is never filtered and thus dependent on stringent watershed protection. This reservoir must meet federal drinking water standards under changing conditions such as increased suburban, commercial, and highway developments that are much higher than the rest of the watershed. Impacts from these sources on water quality are magnified by minor tributary flows subject to contaminants from development projects as other tributaries providing >99% of water to this reservoir are exceedingly clean due to management practices upstream. These threats, coupled with possible changes in the frequency/intensity of weather events due to climate change, increase the potential for contaminants to enter the reservoir and drinking water intakes. This situation provides us with the unique ability to study the effects of weather events on water quality via insignificant storm water inflows, without influence from the major tributaries due to their pristine water quality characteristics. The concentration of contaminants at the drinking water intake depends partially on transport from their point of entry in the reservoir. Thus, it is crucial to understand water circulation in this reservoir and to estimate residence times and water ages at different locations and under different hydrologic scenarios. We described water age, residence time, thermal structure, and flow dynamics of tributary plumes in Kensico Reservoir during a 22-year simulation period using a two-dimensional hydrodynamic and water quality model (CE-QUAL-W2). Our estimates of water age can reach a maximum of ~300 days in deep-reservoir-cells, with

  7. Copper toxicity to the fresh water snail, Lymnaea luteola

    SciTech Connect

    Reddy, N.M.; Rao, P.V.

    1987-07-01

    Haemocyanins are found in arthropoda and mollusca and show a copper content characteristic for each phylum. Heavy metal accumulation by mollusks is widely reported. Approximately one third of the enzymes either required addition of a metal ion as a cofactor in order to exhibit maximum activity or contained a slightly bound metal ion which appeared to be involved in the catalytic process. Copper is the only metal which has been detected in significant amounts in amino oxidase. The present study is designed to evaluate the influence of such copper, which is of such common occurrence in biological material, on some of the lipolytic enzymes of fresh water pulmonate snail, Lymnaea luteola when added to ambient medium. The present study also highlights the possible detoxification mechanism prevailing in this fresh water mollusk.

  8. Identification of Corrosion Products Due to Seawater and Fresh Water

    NASA Astrophysics Data System (ADS)

    Gismelseed, A.; Elzain, M.; Yousif, A.; Al Rawas, A.; Al-Omari, I. A.; Widatallah, H.; Rais, A.

    2004-12-01

    Mössbauer and X-ray diffraction (XRD) measurements were performed on corrosion products extracted from the inner surface of two different metal tubes used in a desalination plant in Oman. One of the tubes corroded due to the seawater while the second was corroded due to fresh water. The corrosion products thus resulted due to seawater were scrapped off in to two layers, the easily removable rust from the top is termed outer surface corrosion product and the strongly adhered rust as internal corrosion product. The Mössbauer spectra together with the XRD pattern of the outer surface showed the presence of magnetite (Fe3O4), akaganeite (β-FeOOH), lepidocrocite (γ-FeOOH), goethite (α-FeOOH) and hematite (Fe2O3). The inner surface however showed the presence of akaganite, goethite, and magnetite. On the other hand, the corrosion products due to the fresh water showed only the presence of goethite and magnetite. The mechanism of the corrosion process will be discussed based on the significant differences between the formation of the iron components of the corrosion products due to seawater and the fresh water.

  9. Innovative Fresh Water Production Process for Fossil Fuel Plants

    SciTech Connect

    James F. Klausner; Renwei Mei; Yi Li; Jessica Knight

    2006-09-29

    This project concerns a diffusion driven desalination (DDD) process where warm water is evaporated into a low humidity air stream, and the vapor is condensed out to produce distilled water. Although the process has a low fresh water to feed water conversion efficiency, it has been demonstrated that this process can potentially produce low cost distilled water when driven by low grade waste heat. This report summarizes the progress made in the development and analysis of a Diffusion Driven Desalination (DDD) system. Detailed heat and mass transfer analyses required to size and analyze the diffusion tower using a heated water input are described. The analyses agree quite well with the current data and the information available in the literature. The direct contact condenser has also been thoroughly analyzed and the system performance at optimal operating conditions has been considered using a heated water/ambient air input to the diffusion tower. The diffusion tower has also been analyzed using a heated air input. The DDD laboratory facility has successfully been modified to include an air heating section. Experiments have been conducted over a range of parameters for two different cases: heated air/heated water and heated air/ambient water. A theoretical heat and mass transfer model has been examined for both of these cases and agreement between the experimental and theoretical data is good. A parametric study reveals that for every liquid mass flux there is an air mass flux value where the diffusion tower energy consumption is minimal and an air mass flux where the fresh water production flux is maximized. A study was also performed to compare the DDD process with different inlet operating conditions as well as different packing. It is shown that the heated air/heated water case is more capable of greater fresh water production with the same energy consumption than the ambient air/heated water process at high liquid mass flux. It is also shown that there can be

  10. A simple method for locating the fresh water-salt water interface using pressure data.

    PubMed

    Kim, Kue-Young; Chon, Chul-Min; Park, Ki-Hwa

    2007-01-01

    Salt water intrusion is a key issue in dealing with exploitation, restoration, and management of fresh ground water in coastal aquifers. Constant monitoring of the fresh water-salt water interface is necessary for proper management of ground water resources. This study presents a simple method to estimate the depth of the fresh water-salt water interface in coastal aquifers using two sets of pressure data obtained from the fresh and saline zones within a single borehole. This method uses the density difference between fresh water and saline water and can practically be used at coastal aquifers that have a relatively sharp fresh water-salt water interface with a thin transition zone. The proposed method was applied to data collected from a coastal aquifer on Jeju Island, Korea, to estimate the variations in the depth of the interface. The interface varied with daily tidal fluctuations and heavy rainfall in the rainy season. The estimated depth of the interface showed a good agreement with the measured electrical conductivity profile.

  11. Caldecott 4th bore tunnel project: influence of ground water flows and inflows triggered by tectonic fault zones?

    NASA Astrophysics Data System (ADS)

    Neuhuber, G.; G. Neuhuber1, W. Klary1, A. Nitschke1, B. Thapa2, Chris Risden3, T. Crampton4, D. Zerga5

    2011-12-01

    nearly perpendicular, separating different geological units were expected along the 4th Bore alignment. This paper will describe encountered ground conditions adjacent to the fault contact where rock conditions are influenced to an extent of 5ft to 85ft from the contact. This paper will also compare the anticipated inflow of 55gpm within 100ft of the top heading excavation and fault zones inflow rates up to 110gpm to the actual measured maximum inflow into the tunnel of150gpm away from fault zones to a maximum inflow between 60gpm and 100gpm near fault zones. In presence of fault zones the water inflow is significant lower than expected and in absence of fault zones higher inflow rates as expected were measured. This paper will discuss the influence of fault zones on the water inflow - or are rock properties and lithology more significant?

  12. Effects of the 2014 major Baltic inflow on methane and nitrous oxide dynamics in the water column of the central Baltic Sea

    NASA Astrophysics Data System (ADS)

    Myllykangas, Jukka-Pekka; Jilbert, Tom; Jakobs, Gunnar; Rehder, Gregor; Werner, Jan; Hietanen, Susanna

    2017-09-01

    In late 2014, a large, oxygen-rich salt water inflow entered the Baltic Sea and caused considerable changes in deep water oxygen concentrations. We studied the effects of the inflow on the concentration patterns of two greenhouse gases, methane and nitrous oxide, during the following year (2015) in the water column of the Gotland Basin. In the eastern basin, methane which had previously accumulated in the deep waters was largely removed during the year. Here, volume-weighted mean concentration below 70 m decreased from 108 nM in March to 16.3 nM over a period of 141 days (0.65 nM d-1), predominantly due to oxidation (up to 79 %) following turbulent mixing with the oxygen-rich inflow. In contrast nitrous oxide, which was previously absent from deep waters, accumulated in deep waters due to enhanced nitrification following the inflow. Volume-weighted mean concentration of nitrous oxide below 70 m increased from 11.8 nM in March to 24.4 nM in 141 days (0.09 nM d-1). A transient extreme accumulation of nitrous oxide (877 nM) was observed in the deep waters of the Eastern Gotland Basin towards the end of 2015, when deep waters turned anoxic again, sedimentary denitrification was induced and methane was reintroduced to the bottom waters. The Western Gotland Basin gas biogeochemistry was not affected by the inflow.

  13. A method for simultaneous estimation of groundwater evapotranspiration and inflow rates in the discharge area using seasonal water table fluctuations

    NASA Astrophysics Data System (ADS)

    Jiang, Xiao-Wei; Sun, Zhi-Chao; Zhao, Ke-Yu; Shi, Fu-Sheng; Wan, Li; Wang, Xu-Sheng; Shi, Zhe-Ming

    2017-05-01

    As an indispensable component of groundwater circulation, groundwater evapotranspiration rate (ETG) estimation using water table fluctuations is a hot research topic in the past decades. However, most existing methods for estimating ETG using either diurnal or seasonal water table fluctuations are based on the assumptions that groundwater recharge equals 0 in the whole period and ETG equals 0 in a specific duration of time. The aim of the current study is to develop a method to estimate ETG when both assumptions do not apply. In the discharge area of a semi-arid catchment in the Ordos Plateau, NW China, it is found out that the water table fluctuations are influenced greatly by recharge, ETG and the vertical inflow rate (qin) in the seasonal scale but are controlled by atmospheric pressure instead of evapotranspiration in the diurnal scale, which implies that the existing methods are not applicable. Therefore, we propose a method to estimate ETG and qin using the seasonal water table fluctuations based on the assumptions that qin is stable throughout the year and ETG has a linear relationship to the reference evapotranspiration (ET0). It is found out that qin is around 1.12 mm/d, and the ratio of ETG to ET0 is around 0.4. ETG in April through July with the highest ET0 of the year is found to be around 3 mm/d, which is much larger than qin, thus leads to significant decline in water table. ETG in November with the lowest ET0 of the unfrozen period is found to be 1.0 mm/d, which is slightly smaller than qin, thus results in a weak increase in water table. The vertical component of regional groundwater inflow is found to exceed precipitation recharge, indicating that regional groundwater inflow plays the major role on maintaining the shallow water table in the discharge area. Groundwater evapotranspiration is also found to exceed precipitation recharge in most time of the unfrozen period, indicating a specified-flux upper boundary with water loss in the discharge area

  14. A survey on Tetracapsuloides bryosalmonae infections in Slovene fresh waters.

    PubMed

    Jenčič, V; Zajc, U; Kušar, D; Ocepek, M; Pate, M

    2014-08-01

    Slovenia has no history of health problems related to proliferative kidney disease (PKD) either in farmed or in wild fish. However, due to the past molecular evidence for the presence of Tetracapsuloides bryosalmonae DNA in tissues of some fish from open waters, a survey was conducted on wild salmonids that were primarily sampled for other purposes. In winter 2010-2011, specimens from a total of 244 rainbow trout, Oncorhynchus mykiss (Walbaum), and brown trout, Salmo trutta L., from 30 bodies of fresh water were examined for T. bryosalmonae using a PCR method. The sampled fish showed no clinical signs or gross pathological lesions characteristic of PKD. Nineteen (7.8%) fish from seven (23.3%) fresh waters were positive for T. bryosalmonae. The identity of PCR amplicons was confirmed by sequencing. With one exception, all the positive fish were found in waters from the regions where the average yearly temperatures and the environmental pollution are higher. This preliminary countrywide survey provided the first insight into the situation regarding T. bryosalmonae infection of wild salmonids in Slovenia. © 2013 John Wiley & Sons Ltd.

  15. Increased salinization of fresh water in the Northeastern United States

    USGS Publications Warehouse

    Kaushal, S.S.; Groffman, P.M.; Likens, G.E.; Belt, K.T.; Stack, W.P.; Kelly, V.R.; Band, L.E.; Fisher, G.T.

    2005-01-01

    Chloride concentrations are increasing at a rate that threatens the availability of fresh water in the northeastern United States. Increases in roadways and deicer use are now salinizing fresh waters, degrading habitat for aquatic organisms, and impacting large supplies of drinking water for humans throughout the region. We observed chloride concentrations of up to 25% of the concentration of seawater in streams of Maryland, New York, and New Hampshire during winters, and chloride concentrations remaining up to 100 times greater than unimpacted forest streams during summers. Mean annual chloride concentration increased as a function of impervious surface and exceeded tolerance for freshwater life in suburban and urban watersheds. Our analysis shows that if salinity were to continue to increase at its present rate due to changes in impervious surface coverage and current management practices, many surface waters in the northeastern United States would not be potable for human consumption and would become toxic to freshwater life within the next century. ?? 2005 by The National Academy of Sciences of the USA.

  16. The partitioning of 7beryllium in fresh water

    NASA Astrophysics Data System (ADS)

    Hawley, N.; Robbins, J. A.; Eadie, B. J.

    1986-06-01

    Field observations and experimental measurements of the partitioning coefficient ( Kd) of 7Be in fresh water show that it varies inversely with the solids concentration at typical environmental values (up to 30 mg/1). This behavior is similar to that of many other metals and organic pollutants, which means that 7Be may be useful as a tracer of the movement of these substances in the water column. However, the wide range in the percentage of 7Be adsorbed by solids over this range of concentrations (over 50%) means that in order to use 7Be either to measure total sedimentation rates or to trace lateral sediment movement it will be necessary to monitor changes in sediment concentration over the area and time period of interest. The wide scatter in our data at both high and low solids concentrations suggests that other factors also affect Kd. Until these factors are identified, application of our results to other systems will be risky. At high (greater than 100 mg/1) solids concentrations over 90% of 7Be is associated with the solid phase, so it may be a useful tracer of reworking rates in bottom sediments. 7Be has a slightly greater affinity for the solid phase in fresh water than in seawater.

  17. Striped bass: environmental risks in fresh and salt water

    SciTech Connect

    Coutant, C.C.

    1985-01-01

    At the 112th Annual meeting of the American Fisheries Society (AFS) at Hilton Head Island, South Carolina, the society held a 1-day symposium Striped Bass: Environmental Risks in Fresh and Salt Water. This issue of the Transactions contains some of the papers from that symposium. This symposium explored several hypotheses about sources of environmental risks that could cause problems for striped bass populations: (1) habitat squeeze on adults stemming from their thermal and dissolved oxygen requirements; (2) stress from toxic materials; and (3) meteorological controls of living space and food. A nonenvironmental factor, fishing pressure, also was raised as an alternative hypothesis.

  18. Fresh Water Generation from Aquifer-Pressured Carbon Storage

    SciTech Connect

    Aines, R D; Wolery, T J; Bourcier, W L; Wolfe, T; Haussmann, C

    2010-02-19

    Can we use the pressure associated with sequestration to make brine into fresh water? This project is establishing the potential for using brine pressurized by Carbon Capture and Storage (CCS) operations in saline formations as the feedstock for desalination and water treatment technologies including reverse osmosis (RO) and nanofiltration (NF). Possible products are: Drinking water, Cooling water, and Extra aquifer space for CO{sub 2} storage. The conclusions are: (1) Many saline formation waters appear to be amenable to largely conventional RO treatment; (2) Thermodynamic modeling indicates that osmotic pressure is more limiting on water recovery than mineral scaling; (3) The use of thermodynamic modeling with Pitzer's equations (or Extended UNIQUAC) allows accurate estimation of osmotic pressure limits; (4) A general categorization of treatment feasibility is based on TDS has been proposed, in which brines with 10,000-85,000 mg/L are the most attractive targets; (5) Brines in this TDS range appear to be abundant (geographically and with depth) and could be targeted in planning future CCS operations (including site selection and choice of injection formation); and (6) The estimated cost of treating waters in the 10,000-85,000 mg/L TDS range is about half that for conventional seawater desalination, due to the anticipated pressure recovery.

  19. Occurrence of human enteric viruses at freshwater beaches during swimming season and its link to water inflow.

    PubMed

    Lee, Chang Soo; Lee, Cheonghoon; Marion, Jason; Wang, Qiuhong; Saif, Linda; Lee, Jiyoung

    2014-02-15

    Human enteric viruses are significant etiological agents for many recreational waterborne illnesses. The occurrence and density of human enteric viruses such as human adenovirus (HAdV), human enterovirus (HEnV), and human norovirus genogroups I/II (HNoV GI/GII) were investigated using quantitative real-time PCR (qPCR) at freshwater beaches along with monitoring fecal indicators and environmental parameters. During the 2009 swimming season, water samples were collected from three inland freshwater beaches in Ohio, USA. Of the total samples, 40% (26/65) and 17% (11/65) were positive for HAdV and HEnV respectively, but HNoV GI/GII were not detected. There was no significant association among the detected human enteric viruses (HAdV and HEnV) and fecal bacteria indicators (Escherichia coli and Bacteroides) by Spearman correlation and principal component analyses. Logistic regression analysis also revealed that the odds of finding HAdV or HEnV was not influenced by levels of fecal bacteria indicators. However, there was a 14-fold increase in the odds of HEnV detection for each 1-log increase in daily water inflow (m(3)/s) into freshwater beach reservoirs (adjusted odds ratio=14.2; 95% confidence interval=1.19-171). In summary, the viral occurrence at the freshwater beaches was not readily explained by the levels of fecal bacteria indicators, but appeared to be more related to water reservoir inflows. These results suggest that hydrological data must be considered in future epidemiology efforts aimed at characterizing beach water safety. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. WATER, ENERGY AND LIFE: FRESH VIEWS FROM THE WATER'S EDGE.

    PubMed

    Pollack, G H

    2010-12-03

    Recent observations have shown an unexpected feature of water adjacent to hydrophilic surfaces: the presence of wide interfacial zone that excludes solutes. The exclusion zone is charged, while the water beyond is oppositely charged, yielding a battery-like feature. The battery is powered by absorbed radiant energy. Implications of this energetic feature are discussed. It appears that the presence of this 'exclusion zone' may play an important role in the behavior of aqueous systems.

  1. Status of fresh water mussel research in Virginia

    SciTech Connect

    Neves, R.J.

    1983-10-01

    In addition to the previously described mussel research projects in Virginia, the Tennessee Valley Authority (TVA) has undertaken a wide-ranging Cumberlandian Mollusc Conservation Program to (a) accumulate information on the present distribution, life histories, and ecological requirements of the Cumberlandian mussel fauna and (b) conserve or increase populations of these species in the Tennessee River drainage. This TVA program has contributed greatly toward a better understanding of species status, water quality problems, and research needs for this unique faunal group. The attention currently being given to fresh water mussels in the upper Tennessee River system is unprecedented, and participating State and Federal agencies are to be commended for supporting conservation activities far beyond what is legally required. The success of a mollusk conservation effort will depend on public awareness, not of mussels in and for themselves but as indicators of riverine degradation and its effect on environmental health and recreational opportunities for man.

  2. [Water and suspended matter sampling in fresh water networks].

    PubMed

    Galas, Chiara; Stellato, Luisa; Barbizzi, Sabrina; Belli, Maria; Sansone, Umberto

    2005-01-01

    Metals and radionuclides in water systems can be easily adsorbed on suspended matter and, finally, they could eventually accumulate in the aquatic environment. The assessment of the health of a water body needs also sampling of the suspended matter fraction. In this paper sampling systems to characterise contaminants associated with the suspended matter fraction are described, with a particular attention to the collection and preservation of samples. Sampling must be representative, to obtain reliable conclusions. In this context it is stressed the importance of the evaluation of the sampling uncertainty, which contributes to a large extent to the total uncertainty.

  3. Water-Quality Data Collected from Vallecito Reservoir, Its Inflows and Outflow, Southwestern Colorado, 1999-2002

    USGS Publications Warehouse

    Ranalli, Anthony J.

    2008-01-01

    The Pine River Watershed Stakeholders Group was created in December 1997 to allow local participation in addressing water-quality issues in Los Pi?os River watershed, including Vallecito Reservoir in southwestern Colorado. One water-quality issue identified by the stakeholder group is to increase the understanding of the current water quality of Vallecito Reservoir, its two major inflows, and its outflow. The U.S. Geological Survey (USGS), in cooperation with volunteers from the Pine River Watershed Stakeholders Group and the U.S. Environmental Protection Agency (USEPA), U.S. Bureau of Reclamation (BOR), Colorado Department of Public Health and Environment (CDPHE), Pine River Irrigation District, Southern Ute Tribe, San Juan Basin Health Department, and San Juan Resource Conservation and Development, collected water-quality samples from Vallecito Reservoir, its two major inflows, and its outflow between August 1999 and November 2002 at about monthly intervals from April through November. The water-quality samples were analyzed for total and dissolved metals (aluminum, arsenic, cadmium, copper, chromium, iron, lead, manganese, mercury, nickel, silver, and zinc), dissolved major ions (calcium, magnesium, sodium, potassium, chloride, bicarbonate, and sulfate), dissolved silica, dissolved organic carbon (DOC), ultraviolet (UV) absorbance at 254 and 280 nanometers, nutrients (total organic nitrogen, dissolved organic nitrogen, dissolved ammonia, dissolved nitrate, total phosphorus, dissolved phosphorus, and orthophosphate), chlorophyll-a (reservoir only), and suspended sediment (inlets to the reservoir only). Measurements of field properties (pH, specific conductance, water temperature, and dissolved oxygen) were also made at each sampling site each time a water-quality sample was collected. This report documents (1) sampling sites and times of sample collection, (2) sample-collection methods, (3) laboratory analytical methods, and (4) responsibilities of each agency

  4. Water age, exposure time, and local flushing time in semi-enclosed, tidal basins with negligible freshwater inflow

    NASA Astrophysics Data System (ADS)

    Viero, Daniele Pietro; Defina, Andrea

    2016-04-01

    Within the framework of tidally flushed, semi-enclosed basins with negligible freshwater inflow, and under steady periodic flow conditions, three frequently used local transport time scales to quantify the efficiency of water renewal, namely water age, exposure time, and local flushing time are studied and compared to each other. In these environments, water renewal is strongly controlled by diffusion, and it is significantly affected by the return flow (i.e., the fraction of effluent water that returns into the basin on each flood tide). The definition of water age is here modified to account for the return flow, in analogy with exposure time and local flushing time. We consider approximate time scales, whose accuracy is analyzed, in order to overcome problems related to the size of the computational domain and to reduce the computational effort. A new approximate procedure is introduced to estimate water age, which is based on the water aging rate. Also, the concept of local flushing time as a relevant time scale is introduced. Under steady periodic conditions, we demonstrate that the local flushing time quantitatively corresponds to water age, and well approximates exposure time when the flow is dominated by diffusion. Since the effort required to compute water age and exposure time is greater than that required to compute the local flushing time, the present results can also have a practical interest in the assessment of water renewal efficiency of semi-enclosed water basins. The results of a modeling study, in which the lagoon of Venice is used as a benchmark, confirm the substantial quantitative equivalence between these three transport time scales in highly diffusive environments.

  5. The Baltic Inflow Event 2014 and its Biogeochemical Response in the Anoxic Central Baltic Basins

    NASA Astrophysics Data System (ADS)

    Schulz-Bull, D. E.; Naumann, M.; Mohrholz, V.; Nausch, G.; Prien, R. D.

    2016-02-01

    The brackish Baltic Sea and the deeper anoxic basins in the central parts are occasionally ventilated by the intrusion of high saline and oxygen rich water from the North Atlantic entering the Baltic Sea. With a volume of 198 km3 containing 4 Gt salt, the inflow event in 2014 was the third largest ever observed. As a result the redox conditions in the anoxic parts of the Baltic Sea changed. In the Bornholm Basin and the Gotland Deep area the biogeochemical conditions for many elements and redox sensitive substances changed crucial by the inflow water. Oxidation of the hydrogen sulfide and consequent changes in the pH and the carbonate system were observed. Other chemicals such as the nitrogen nutrients, phosphate, trace metals and the dissolved organic matter react with the fresh inflow water ingredients. The chronological sequence of the biogeochemical reactions following the inflow event where monitored by autonomous stations and several ship expeditions in high spatial and temporal resolution.

  6. Water dynamics in fresh and frozen yeasted dough.

    PubMed

    Loveday, Simon M; Huang, Victor T; Reid, David S; Winger, Ray J

    2012-01-01

    Water is an integral part of wheat flour dough-the amount, physical state, and location of water are crucial to the formation of a dough that will hold gas and produce an open, aerated crumb structure in the final product. This has been understood for centuries by craft bakers, who were highly attuned to the "feel" of dough in their hands. In the 20th century, empirical instruments were invented that simulated part of the breadmaking process, and their limited predictive capacity made them valuable quality control tools. During the latter decades of the 20th century the cost and availability of advanced instrumental methods for characterizing foods improved dramatically, and facilitated a "fundamental science" approach to food research. The physicochemical mechanisms by which water exerts such a strong influence on the character of dough are now better understood. This review contrasts the empirical and fundamental view points, and summarizes recent knowledge about the roles of water in the manufacture of fresh and frozen yeasted dough.

  7. Biosorption of Lead from Wastewater Using Fresh Water Algae Chlorella.

    PubMed

    Kanchana, S; Jeyanthi, J

    2014-04-01

    The potential use of fresh water algae Chlorella to sorb lead ions from wastewater was evaluated in this study. Fourier transform infra-red analysis of algal species revealed the presence of amino, carboxylic, hydroxyl and carbonyl groups, which were responsible for biosorption of lead ions. Batch sorption experiments were performed to determine the effects of contact time, biosorbent dosage and pH on the adsorption of Pb2+ ions. The optimum conditions of biosorbent dosage, pH and contact time were found to be l0 g/L, 5 and 100 min respectively. The applicability of the Langmuir and Freundlich isotherms for representation of the experimental data was investigated. The adsorption of lead ions on the algae Chlorella fitted well with Freundlich isotherm with a very high correlation coefficient.

  8. Moisture Advection and Fresh Water Flux over Oceans

    NASA Technical Reports Server (NTRS)

    Tang, Wenqing; Liu, W. Timothy

    2002-01-01

    Moisture transport in the atmosphere is one of the most significant components in the hydrological cycle. Under stationary condition, ocean surface fresh water flux, which is the difference between precipitation (P) and evaporation (E), is balanced by the divergence of column-integrated moisture transport (IMT) in the atmosphere. Characterizing accurately a global picture of IMT from observation is a difficult task. It requires measurements of vertical profiles for wind vector and humidity. More specifically, IMT can be defined as the integration in pressure coordinates the product of specific humidity q and wind vector u, where g is the gravitational acceleration, and p, is the atmospheric pressure at ocean surface.In this study, a statistical relationship is derived between u, and u(sub)s using data from numerical weather prediction model. The relationship is then validated using surface and vertical profile from radiosonde data, before applied to spacebased measurements.

  9. Flood risk assessment of fresh water supply systems

    NASA Astrophysics Data System (ADS)

    Arrighi, Chiara; Tarani, Fabio; Vicario, Enrico; Castelli, Fabio

    2017-04-01

    Flooding is a common hazard causing damages to people, buildings and infrastructures. Often located in low-lying areas or nearby rivers, water utilities are particularly vulnerable to flooding. Water and debris can inundate the facility, thereby damaging equipment and causing power outages. Such impacts can lead to costly repairs, disruptions of service, hazardous situations for personnel and public health advisories. While flood damage evaluation to buildings and their contents is becoming increasingly available, the quantification of impact on critical infrastructures is less common. In this work, we present the flood risk assessment of a fresh water supply system considering the hazard of a riverine flooding and exposure and vulnerability of the system components (i.e. pipes, junctions, lifting stations etc.). The evaluation of flood impact on the aqueduct network is carried out for flood scenarios with assigned recurrence intervals. Vulnerable elements exposed to the flood are identified and analysed in order to determine their residual functionality. Above a selected threshold, the affected elements are considered as failed. The water distribution piping system is modelled through a model based on EPANET designed so as to implement Pressure-Driven Demand (PDD), which is more appropriate when modelling water distribution networks with a high number of offline nodes. Results of piping system model affected by the flood are then compared in a QGIS environment with flood depth to identify the location of service outages and potential risk of contamination. The application to the water supply system of the city of Florence (Italy), serving approximately 385000 inhabitants through 900 km of piping is presented and discussed.

  10. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi)

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Patterson, R. M.; Wade, C. E.; Byers, F. M.

    2000-01-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  11. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi).

    PubMed

    Ortiz, R M; Patterson, R M; Wade, C E; Byers, F M

    2000-09-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  12. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi)

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Patterson, R. M.; Wade, C. E.; Byers, F. M.

    2000-01-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  13. Investigating the influence of Atlantic water inflow on primary production in a regional model for the Fram Strait

    NASA Astrophysics Data System (ADS)

    Samuelsen, Annette

    2016-04-01

    A regional model for the Fram Strait with resolution 3.5 km has been set up as a coupled physical-biogeochemical model, HYCOM-NORWECOM, nested into a 15-km basin-scale model for the North Atlantic and Arctic. Both the basin scale and regional model has been compared to the same in-situ dataset covering mostly the eastern part of the Fram Strait. In the Fram Strait flow of Atlantic water on one side of the strait and Arctic water on the other side of the strait influences, temperature, salinity and nutrient availability which in turn influencing the primary production in the strait. In particular the ratio of silicate to nitrate differs across he strait and it is hypothesized that this difference causes in addition to the physical environment influences the relative abundance of diatoms and flagellates across the strait. Using the model we investigate how the inflow of Atlantic water in the model affect the ecosystem in the Fram Strait and which factors controlling the primary production and phytoplankton composition.

  14. Investigating the influence of Atlantic water inflow on primary production in a regional model for the Fram strait

    NASA Astrophysics Data System (ADS)

    Samuelsen, A.

    2016-02-01

    A regional model for the Fram Strait with resolution 3.5 km has been set up as a coupled physical-biogeochemical model, HYCOM-NORWECOM, nested into a 15-km basin-scale model for the North Atlantic. Both the basin scale and regional model has been compared to the same in-situ dataset covering mostly the eastern part of the Fram Strait. In the Fram Strait flow of Atlantic water on one side of the strait and Arctic water on the other side of the strait influences, temperature, salinity and nutrient availability which in turn influencing the primary production in the strait. In particular the ratio of silicate to nitrate differs across he strait and it is hypothesized that this difference causes in addition to the physical environment influences the relative abundance of diatoms and flagellates across the strait. Using the model we investigate how the inflow of Atlantic water in the model affect the lower trophic levels of the ecosystem in the Fram Strait and which factors control the primary production and phytoplankton composition.

  15. Biological Status Monitoring of European Fresh Water with Sentinel-2

    NASA Astrophysics Data System (ADS)

    Serra, Romain; Mangin, Antoine; Fanton d'Andon, Odile Hembise; Lauters, Francois; Thomasset, Franck; Martin-Lauzer, Francois-Regis

    2016-08-01

    Thanks to a widening range of sensors available, the observation of continental water quality for lakes and reservoirs is gaining more and more consistency and accuracy.Consistency because back in 2012, the only free sensor with a sufficient resolution (30m) was Landsat-7 which has truncated data since 2003 and a 16-day revisit time. But today, Landsat-8 and Sentinel-2A are now operating so depending on the latitude of interest, the combined revisit time dropped to 2 to 4 days which is more appropriate for such a monitoring (especially considering the cloud cover).Accuracy because Landsat-7 has a poor contrast over water whereas Landsat-8 and Sentinel-2A have a better radiometric sensitivity (more bit) and moreover Sentinel-2 offers additional spectral bands in the visible which are helpful for Chlorophyll-A concentration assessment. To sum up, with Sentinel-2, continental water quality monitoring capabilities are making a giant leap and it is important to exploit this potential the sooner. ACRI-HE has already built a strong basis to prepare Sentinel-2 by using Landsat data.Indeed, more than 600 lakes are already constantly monitored using Landsat data and their biological statuses are available on EyeOnWater (see eyeonwater.eu). Chlorophyll-A retrieval from (fresh) water leaving reflectances is the result of research activities conducted by ACRI-HE in parallel with EDF (Electricité de France) to respond to an emerging very demanding environmental monitoring through European regulations (typically the Water Framework Directive). Two parallel and complementary algorithms have thus been derived for Chlorophyll-a retrieval.Upstream of Eyeonwater, there is a complex and complete system automatically collecting images, extracting areas of interest around lakes, applying atmospheric correction (very sensitive part as atmosphere can contribute to 90% of the signal at sensor level) and then algorithms to retrieve water transparency (Secchi disk), turbidity and Chlorophyll

  16. Material Excavated by a Fresh Impact and Identified as Water Ice

    NASA Image and Video Library

    2009-09-24

    The Compact Reconnaissance Imaging Spectrometer for Mars, an instrument on NASA Mars Reconnaissance Orbiter, obtained information confirming material excavated by a fresh impact and Identified as water ice.

  17. Increasing water stress negatively affects pear fruit growth by reducing first its xylem and then its phloem inflow.

    PubMed

    Morandi, Brunella; Losciale, Pasquale; Manfrini, Luigi; Zibordi, Marco; Anconelli, Stefano; Galli, Fabio; Pierpaoli, Emanuele; Corelli Grappadelli, Luca

    2014-10-15

    Drought stress negatively affects many physiological parameters and determines lower yields and fruit size. This paper investigates on the effects of prolonged water restriction on leaf gas exchanges, water relations and fruit growth on a 24-h time-scale in order to understand how different physiological processes interact to each other to face increasing drought stress and affect pear productive performances during the season. The diurnal patterns of tree water relations, leaf gas exchanges, fruit growth, fruit vascular and transpiration flows were monitored at about 50, 95 and 145 days after full bloom (DAFB) on pear trees of the cv. Abbé Fétel, subjected to two irrigation regimes, corresponding to a water restitution of 100% and 25% of the estimated Etc, respectively. Drought stress progressively increased during the season due to lower soil tensions and higher daily vapour pressure deficits (VPDs). Stem water potential was the first parameter to be negatively affected by stress and determined the simultaneous reduction of fruit xylem flow, which at 95 DAFB was reflected by a decrease in fruit daily growth. Leaf photosynthesis was reduced only from 95 DAFB on, but was not immediately reflected by a decrease in fruit phloem flow, which instead was reduced only at 145 DAFB. This work shows how water stress negatively affects pear fruit growth by reducing first its xylem and then its phloem inflow. This determines a progressive increase in the phloem relative contribution to growth, which lead to the typical higher dry matter percentages of stressed fruit. Copyright © 2014. Published by Elsevier GmbH.

  18. Example calculations of possible ground-water inflow to mine pits at the West Decker, East Decker, and proposed North Decker mines, southeastern Montana

    USGS Publications Warehouse

    Davis, R.E.

    1984-01-01

    Proposed plans to raise the spillway of the Tongue River Dam, Montana, 14 feet would result in an increase in the reservoir stage, which will affect the amount of ground-water inflow from the reservoir to existing and proposed surface coal mine pits near Tongue River Reservoir. Example calculations are based on flow from the reservoir to the mine pits through areas approximately perpendicular to the long axis of the reservoir. The planned increase in the stage of the reservoir will result in an increase of inflow to the mine pits in most areas. The increases will be greatest where the mine pits are near the reservoir and separated from the reservoir solely by aquifer zones of relatively large hydraulic conductivity. However, the inflow determined from the calculations is subject to a large degree of error, owing to the simplified method of calculation and the assumptions used. (USGS)

  19. Inflow rate-driven changes in the composition and dynamics of chromophoric dissolved organic matter in a large drinking water lake.

    PubMed

    Zhou, Yongqiang; Zhang, Yunlin; Jeppesen, Erik; Murphy, Kathleen R; Shi, Kun; Liu, Mingliang; Liu, Xiaohan; Zhu, Guangwei

    2016-09-01

    Drinking water lakes are threatened globally and therefore in need of protection. To date, few studies have been carried out to investigate how the composition and dynamics of chromophoric dissolved organic matter (CDOM) in drinking water lakes are influenced by inflow rate. Such CDOM can lead to unpleasant taste and odor of the water and produce undesirable disinfection byproducts during drinking water treatment. We studied the drinking water Lake Qiandao, China, and found that the concentrations of suspended particulate matter (SPM) in the lake increased significantly with inflow rate (p < 0.001). Similarly, close relationships between inflow rate and the CDOM absorption coefficient at 350 nm a(350) and with terrestrial humic-like fluorescence C3 and a negative relationship between inflow rate and the first principal component (PC1) scores, which, in turn, were negatively related to the concentrations and relative molecular size of CDOM (p < 0.001), i.e. the concentration and molecular size of CDOM entering the lake increased proportionately with inflow rate. Furthermore, stable isotopes (δD and δ(18)O) were depleted in the upstream river mouth relative to downstream remaining lake regions, substantiating that riverine CDOM entering the lake was probably driven by inflow rate. This was further underpinned by remarkably higher mean chlorophyll-a and in situ measured terrestrial CDOM fluorescence (365/480 nm) and apparent oxygen utilization (AOU), and notably lower mean PC1 and CDOM spectral slope (S275-295) recorded in the upstream river mouth than in the downstream main lake area. Strong negative correlations between inflow rate and a(250):a(365), S275-295, and the spectral slope ratio (SR) implied that CDOM input to the lake in rainy period was dominated by larger organic molecules with a more humic-like character. Rainy period, especially rainstorm events, therefore poses a risk to drinking water safety and requires higher removal efficiency of CDOM

  20. Effects of warm water inflows on the dispersion of pollutants in small reservoirs.

    PubMed

    Palancar, María C; Aragón, José M; Sánchez, Fernando; Gil, Roberto

    2006-11-01

    The effects of the warm water discharged by a nuclear power plant (NPP) into a small reservoir are studied. A case study is presented (José Cabrera NPP-Zorita Hidráulica Reservoir) with experimental data of the reservoir stratification and predicted data of the dispersion of radioactive pollutants from operative or accidental releases. The vertical and longitudinal temperature profiles, electrical conductivity and transparency of the reservoir water were measured for an annual cycle. The results indicate that the continuous warm water discharge from the NPP causes permanent and artificial reservoir stratification. The stratification is significant within 1500 m upstream and 1000 m downstream from the warm water outfall. The pollutant dispersion has been predicted by using a flow model based on N(T) perfect-mixing compartments in series with feedback. The model parameter, N(T), is calculated from the longitudinal diffusion coefficient. The prediction of pollutant dispersion by means of this model shows that the stratification slows down the vertical mixing in the whole water body, and reduces the reservoir volume that is effective for the dilution and dispersion of pollutants. This means that, in the case of a radioactive pollutant release, the reservoir radioactivity level could increase significantly.

  1. Incorporating Seasonal Forecast of Inflow into Existing Water Resource Management at Ubolratana Dam, Thailand

    NASA Astrophysics Data System (ADS)

    Chatikavanij, V.; Block, P. J.; Lall, U.

    2011-12-01

    Seasonal forecast of streamflow, coupled with dynamic reservoir operation policy, has been shown to improve water allocation and flood control. By considering current and expected future reservoir level, water managers can make more adaptive and informed judgments about reservoir operation and allocation policy. While seasonal forecast application has shown substantial positive results, its adoption is still lagging due to the difficulties in integrating forecast into the current reservoir management system. This project offers a simple framework for incorporating seasonal streamflow forecasts into existing operation to optimize reservoir management decisions at the Ubolratana Dam in the Northeastern region of Thailand. The framework allows for the retention of existing reservoir policy while altering the application of the upper rule curve based on forecast information. Our objective is to maximize water release for hydropower generation, minimize spill and shortages while meeting demands for irrigation and water quality control during the peak summer monsoon season. Climate variables, including sea-surface temperature and sea-level pressure in March-May, are used to develop streamflow forecast ensembles for September-November. We use a dynamically linked system of forecast and reservoir management models to specify operating rules for end of the month storage levels at the Ubolratana Reservoir. Benefits and reliability based on the forecast ensembles are compared with historical operations and a climatological-based approach. Forecast ensembles are also divided into terciles to evaluate performance during dry and wet years, of particular interest to water managers. Results demonstrate that the dynamic operations contingent on forecasts may increase water releases for hydropower, decrease spill and deficit, and improve reliability compared with the status quo.

  2. Characteristic of pollution with groundwater inflow (90)Sr natural waters and terrestrial ecosystems near a radioactive waste storage.

    PubMed

    Lavrentyeva, G V

    2014-09-01

    The studies were conducted in the territory contaminated by (90)Sr with groundwater inflow as a result of leakage from the near-surface trench-type radioactive waste storage. The vertical soil (90)Sr distribution up to the depth of 2-3 m is analyzed. The area of radioactive contamination to be calculated with a value which exceeds the minimum significant activity 1 kBq/kg for the tested soil layers: the contaminated area for the 0-5 cm soil layer amounted to 1800 ± 85 m(2), for the 5-10 cm soil layer amounted to 300 ± 12 m(2), for the 10-15 cm soil layer amounted to 180 ± 10 m(2). It is found that (90)Sr accumulation proceeds in a natural sorption geochemical barrier of the marshy terrace near flood plain. The exposure doses for terrestrial mollusks Bradybaena fruticum are presented. The excess (90)Sr interference level was registered both in the ground and surface water during winter and summer low-water periods and autumn heavy rains. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Fresh Waters and Fish Diversity: Distribution, Protection and Disturbance in Tropical Australia

    PubMed Central

    Januchowski-Hartley, Stephanie R.; Pearson, Richard G.; Puschendorf, Robert; Rayner, Thomas

    2011-01-01

    Background Given the globally poor protection of fresh waters for their intrinsic ecological values, assessments are needed to determine how well fresh waters and supported fish species are incidentally protected within existing terrestrial protected-area networks, and to identify their vulnerability to human-induced disturbances. To date, gaps in data have severely constrained any attempt to explore the representation of fresh waters in tropical regions. Methodology and Results We determined the distribution of fresh waters and fish diversity in the Wet Tropics of Queensland, Australia. We then used distribution data of fresh waters, fish species, human-induced disturbances, and the terrestrial protected-area network to assess the effectiveness of terrestrial protected areas for fresh waters and fish species. We also identified human-induced disturbances likely to influence the effectiveness of freshwater protection and evaluated the vulnerability of fresh waters to these disturbances within and outside protected areas. The representation of fresh waters and fish species in the protected areas of the Wet Tropics is poor: 83% of stream types defined by order, 75% of wetland types, and 89% of fish species have less than 20% of their total Wet Tropics length, area or distribution completely within IUCN category II protected areas. Numerous disturbances affect fresh waters both within and outside of protected areas despite the high level of protection afforded to terrestrial areas in the Wet Tropics (>60% of the region). High-order streams and associated wetlands are influenced by the greatest number of human-induced disturbances and are also the least protected. Thirty-two percent of stream length upstream of protected areas has at least one human-induced disturbance present. Conclusions/Significance We demonstrate the need for greater consideration of explicit protection and off-reserve management for fresh waters and supported biodiversity by showing that, even in

  4. Wet Worlds: Explore the World of Water. Marine and Fresh Water Activities for the Elementary Classroom.

    ERIC Educational Resources Information Center

    Solomon, Gerard; And Others

    Complete with student worksheets, field trip ideas, illustrations, vocabulary lists, suggested materials, and step-by-step procedures, the document presents a compilation of ideas for teaching elementary school (K-6) students about marine and fresh water. In the first unit students build miniature monuments and observe the deterioration of…

  5. Arenimonas maotaiensis sp. nov., isolated from fresh water.

    PubMed

    Yuan, Xin; Nogi, Yuichi; Tan, Xu; Zhang, Ren-Gang; Lv, Jie

    2014-12-01

    A translucent, white, Gram-reaction-negative, facultatively anaerobic, non-flagellated, slightly curved or curved bacterial strain, designated YT8(T), was isolated from the fresh water of the Maotai section of Chishui River, China. Cells were catalase-positive and oxidase-positive. Phylogenetic analyses of 16S rRNA gene sequences revealed that strain YT8(T) is a member of the genus Arenimonas with similarity to other members of this genus ranging from 93.7 to 95.0 %. The major isoprenoid quinone was ubiquinone 8 (Q-8), major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, two unidentified phospholipids and two unidentified polar lipids, while major fatty acids were iso-C15 : 0, iso-C14 : 0 and anteiso-C15 : 0. The DNA G+C content of strain YT8(T) was 66.6 mol%. On the basis of phenotypic, phylogenetic and genotypic features studied, strain YT8(T) is suggested to represent a novel species of the genus Arenimonas, for which the name Arenimonas maotaiensis sp. nov. is proposed. The type strain is YT8(T) ( = CGMCC 1.12726(T) = JCM 19710(T)).

  6. Mucilaginibacter aquaedulcis sp. nov., isolated from fresh water.

    PubMed

    Joung, Yochan; Kang, Heeyoung; Lee, Beom-Il; Kim, Haneul; Joh, Kiseong; Kim, Kyu-Joong

    2015-02-01

    An aerobic, Gram-stain-negative, rod-shaped bacterium, designated strain PGW1-R01(T), was isolated from fresh water from the Yeongju in the Republic of Korea. The strain grew optimally at 30 °C and at pH 6-8 on R2A agar. The major cellular fatty acids were summed feature 3 [comprising C16 : 1ω7c and/or C16 : 1ω6c (50.2 %) and iso-C15 : 0 (24.8 %)]. The major respiratory quinone was MK-7. The G+C contents were 39.4 mol% and the predominant respiratory quinone was MK-7. Based on 16S rRNA gene phylogeny, the strain belongs to the genus Mucilaginibacter. The strain PGW1-R01(T) was closely related to 'Mucilaginibacter ginsenosidivorax' (96.6 % sequence similarity), Mucilaginibacter lappiensis (96.4 %) and Mucilaginibacter flavus (96.4 %). On the basis of the evidence presented in this study, strain PGW1-R01(T) represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter http://dx.doi.org/10.1601/nm.11437aquaedulcis sp. nov., is proposed. The type strain is PGW1-R01(T)( = KCTC 23942(T) = CECT 8102(T)).

  7. The Subpolar Gyre - a regulator for the inflow of Atlantic water to the Nordic Seas

    NASA Astrophysics Data System (ADS)

    Hatun, H.; Sandoe, A.; Drange, H.; Bentsen, M.

    2004-12-01

    As shown by Hakkinen & Rhines (2004), the sea level within the Subpolar Gyre, as determined by altimetry, has been increasing throughout the nineties and in the beginning of 21st century. This has resulted in a weakened baroclinic rim-current around the Gyre during this period. Here we show that the prominent increase in temperature and salinity in the Northeastern North Atlantic during the last decade is linked to the weakened Gyre conditions. In order to further explore the nature of the decadal scale variations of hydrography and volume transports of the pole-ward flowing Atlantic water crossing the Iceland-Scotland Ridge a numerical model is invoked. A 53 years hind-cast simulation with a regional version of the Nansen Center version of the Miami Isopycnic Coordinate Ocean Model (MICOM) indicates large variations in volume transport of Atlantic water through the Iceland-Faroe (IF) Gap. The mid 60s, the late 70s to the early 80s showed very weak transports while the periods 1971-1975 and 1989-1994 were characterized by abnormally strong transports. Strong/weak transport periods through IF Gap are concurrent with strong/weak deep convection periods in the Labrador Sea and an expanded/contracted Subpolar Gyre. The simulated transport through the IF Gap follows the temporal evolution of the sea level within the Subpolar Gyre.

  8. Evaluation of white water reuse in the bleaching process for reducing fresh water consumption.

    PubMed

    Andrade, A A; Glória, P M; d'Angelo, J V H; Perissotto, D O; Lima, R A

    2007-01-01

    The main objective of this work is to study the technical viability of using the effluent generated in paper machines (white water) in the wash presses of the bleaching stage, reducing fresh water consumption. As a case study, the industrial process of Ripasa S.A. Celulose e Papel was evaluated. White water rate is about 700 m3/h and it is not possible to reuse all this volume in the bleaching stage without causing operational problems (fouling in tubes and clogging in the screens). A mass balance of the bleaching unit was developed in an electronic spreadsheet in order to evaluate the possibility of reducing fresh water consumption, using only a fraction of the available white water in the wash presses. To achieve this objective some physical-chemistry properties of the white water stream and of other streams of the process were determined. The maximum concentration of some non-process elements (Si, Ca, Mn and Fe), which could accumulate in the process, were determined in order to establish some parameters to allow process integration of the streams involved, considering operational constraints. The results obtained have shown that it is possible to reduce approximately by 13% the consumption of fresh water and this methodology has been satisfactory.

  9. Fresh water, marine and terrestrial cyanobacteria display distinct allergen characteristics.

    PubMed

    Lang-Yona, Naama; Kunert, Anna Theresa; Vogel, Lothar; Kampf, Christopher Johannes; Bellinghausen, Iris; Saloga, Joachim; Schink, Anne; Ziegler, Kira; Lucas, Kurt; Schuppan, Detlef; Pöschl, Ulrich; Weber, Bettina; Fröhlich-Nowoisky, Janine

    2017-08-31

    During the last decades, global cyanobacteria biomass increased due to climate change as well as industrial usage for production of biofuels and food supplements. Thus, there is a need for thorough characterization of their potential health risks, including allergenicity. We therefore aimed to identify and characterize similarities in allergenic potential of cyanobacteria originating from the major ecological environments. Different cyanobacterial taxa were tested for immunoreactivity with IgE from allergic donors and non-allergic controls using immunoblot and ELISA. Moreover, mediator release from human FcεR1-transfected rat basophilic leukemia (RBL) cells was measured, allowing in situ examination of the allergenic reaction. Phycocyanin content and IgE-binding potential were determined and inhibition assays performed to evaluate similarities in IgE-binding epitopes. Mass spectrometry analysis identified IgE-reactive bands ranging between 10 and 160kDa as phycobiliprotein compounds. Levels of cyanobacterial antigen-specific IgE in plasma of allergic donors and mediator release from sensitized RBL cells were significantly higher compared to non-allergic controls (p<0.01). Inhibition studies indicated cross-reactivity between IgE-binding proteins from fresh water cyanobacteria and phycocyanin standard. We further addressed IgE-binding characteristics of marine water and soil-originated cyanobacteria. Altogether, our data suggest that the intensive use and the strong increase in cyanobacterial abundance due to climate change call for increasing awareness and further monitoring of their potential health hazards. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Effect of Atlantic water inflow on timing of the phytoplankton spring bloom in a high Arctic fjord (Kongsfjorden, Svalbard)

    NASA Astrophysics Data System (ADS)

    Hegseth, Else Nøst; Tverberg, Vigdis

    2013-03-01

    The spring bloom in Kongsfjorden, Svalbard was followed during the years 2006-2008 to study the bloom dynamics in relation to environmental factors. Usual timing of the bloom in this normally ice-filled fjord has been May with few exceptions. But in 2006 the bloom occurred in April. This was the first of 3 consecutive spring seasons with no ice in the fjord. But even so the bloom was delayed until May both in 2007 and 2008. The 2006 bloom was characterized by high phytoplankton biomass and a mix of diatoms and Phaeocystis pouchetii. The 2007 and 2008 spring blooms were delayed until mid/late May, and the biomass and biodiversity were significantly reduced, with a more pronounced dominance of Phaeocystis relative to diatoms. The different bloom developments are discussed in relation to Atlantic water inflow, which varied between the years in question and seemed to be the main controlling factor of the spring blooms. Possible future bloom scenarios are also discussed.

  11. Fresh water leaching of alkaline bauxite residue after sea water neutralization.

    PubMed

    Menzies, Neal W; Fulton, Ian M; Kopittke, Rosemary A; Kopittke, Peter M

    2009-01-01

    Processing of bauxite to extract alumina produces a strongly alkaline waste, bauxite refining residue, which is commonly stored in engineered structures. Once full, these waste dumps must be revegetated. In many alumina refineries, the waste is separated into fine-textured red mud and coarse-textured residue sand (RS). The sand component has physical characteristics that make it a suitable plant growth medium, provided the adverse chemical characteristics can be addressed. Neutralization of the highly saline-sodic RS with sea water lowers pH, reduces Na saturation, and adds plant nutrients. However, sea water-neutralized RS remains saline sodic and needs fresh water leaching before use as a plant growth medium. Columns containing sea water-neutralized RS were leached with 30 m depth-equivalent of fresh water to evaluate the effects of rainfall on the RS and its leachate. Entrained cations were rapidly displaced by the fresh water, lowering salinity to non-plant-limiting levels (< or =0.3 dS m(-1)). The percentage of the effective cation exchange capacity (ECEC) saturated by Na decreased from 71 to 62% due to a reduction in soil solution ionic strength (causing a decrease in the ECEC) and the preferential displacement of Na(+) (and K(+)) from the exchange. Fresh water leaching increased pH (leachate pH increased from 8.0 to 10.1). This pH increase is attributed to the slow dissolution of the Na-containing mineral sodalite. Under the current experimental conditions, the application of 30 m depth-equivalent of leaching reduced the total RS sodalite content by <10%.

  12. Roseomonas sediminicola sp. nov., isolated from fresh water.

    PubMed

    He, Dan; Kim, Jin-Kwang; Jiang, Xiao-Ye; Park, Hye-Yoon; Sun, Changkai; Yu, Hong-San; Yoon, Min-Ho; Kim, Sun-Chang; Jin, Feng Xie; Im, Wan-Taek

    2014-01-01

    A Gram-stain negative, strictly aerobic, non-motile, non-spore-forming, and rod-shaped bacterial strain designated FW-3(T) was isolated from fresh water and its taxonomic position was investigated by using a polyphasic approach. Strain FW-3(T) was found to grow at 10-37 °C and at pH 7.0 in the absence of NaCl on nutrient agar. On the basis of 16S rRNA gene sequence similarity, strain FW-3(T) was shown to belong to the family Acetobacteraceae and to be related to Roseomonas lacus TH-G33(T) (97.2 % sequence similarity) and Roseomonas terrae DS-48(T) (96.4 %). The G+C content of the genomic DNA was determined to be 68.0 %. The major menaquinone was determined to be Q-10 and the major fatty acids were identified as summed feature 7 (comprising C18:1 ω9c/ω12t/ω7c as defined by the MIDI system; 55.4 %), and C18:1 2OH (29.8 %). DNA and chemotaxonomic data supported the affiliation of strain FW-3(T) to the genus Roseomonas. Strain FW-3(T) could be differentiated genotypically and phenotypically from the recognized species of the genus Roseomonas. The novel isolate therefore represents a novel species, for which the name Roseomonas sediminicola sp. nov. is proposed, with the type strain FW-3(T) (=KACC 16616(T) = JCM 18210(T)).

  13. Bacillus rigui sp. nov., isolated from wetland fresh water.

    PubMed

    Baik, Keun Sik; Lim, Chae Hong; Park, Seong Chan; Kim, Eun Mi; Rhee, Moon Soo; Seong, Chi Nam

    2010-09-01

    Two Gram-stain-positive strains, WPCB074(T) and WPCB165, were isolated from fresh water collected from the Woopo wetland (Republic of Korea). Both strains were strictly aerobic, motile, endospore-forming rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains WPCB074(T) and WPCB165 belonged to the genus Bacillus and that strain WPCB074(T) was most closely related to Bacillus solisalsi YC1(T) (98.4 % sequence similarity), B. barbaricus V2-BIII-A2(T) (97.7 %), B. macauensis ZFHKF-1(T) (96.9 %), B. arsenicus Con a/3(T) (96.4 %) and B. gelatini LMG 21880(T) (95.1 %). The 16S rRNA gene sequences of strains WPCB074(T) and WPCB165 differed at one position (99.9 % similarity), suggesting that these two strains constitute a single species. DNA-DNA relatedness between strain WPCB074(T) and the type strains of B. solisalsi, B. barbaricus, B. macauensis, B. arsenicus and B. gelatini were 26, 17, 20, 14 and 7 %, respectively. Strain WPCB074(T) was characterized by having cell-wall peptidoglycan based on meso-diaminopimelic acid, MK-7 as the predominant menaquinone and iso-C(15 : 0) and anteiso-C(15 : 0) as the major fatty acids. The DNA G+C content of strain WPCB074(T) was 41.9 mol%. On the basis of phenotypic properties, phylogeny and genomic distinctiveness, strain WPCB074(T) represents a novel species of the genus Bacillus for which the name Bacillus rigui sp. nov. is proposed. The type strain is WPCB074(T) (=KCTC 13278(T) =JCM 16348(T)).

  14. Investigation and incorporation of water inflow uncertainties through stochastic modelling in a combined optimisation methodology for water allocation in Alfeios River (Greece)

    NASA Astrophysics Data System (ADS)

    Bekri, Eleni; Yannopoulos, Panayotis; Disse, Markus

    2014-05-01

    The Alfeios River plays a vital role for Western Peloponnisos in Greece from natural, ecological, social and economic aspect. The main river and its six tributaries, forming the longest watercourse and the highest streamflow rate of Peloponnisose, represent a significant source of water supply for the region, aiming at delivering and satisfying the expected demands from a variety of water users, including irrigation, drinking water supply, hydropower production and recreation. In the previous EGU General Assembly, a fuzzy-boundary-interval linear programming methodology, based on Li et al. (2010) and Bekri et al. (2012), has been presented for optimal water allocation under uncertain and vague system conditions in the Alfeios River Basin. Uncertainties associated with the benefit and cost coefficient in the objective function of the main water uses (hydropower production and irrigation) were expressed as probability distributions and fuzzy boundary intervals derived by associated α-cut levels. The uncertainty of the monthly water inflows was not incorporated in the previous initial application and the analysis of all other sources of uncertainty has been applied to two extreme hydrologic years represented by a selected wet and dry year. To manage and operate the river system, decision makers should be able to analyze and evaluate the impact of various hydrologic scenarios. In the present work, the critical uncertain parameter of water inflows is analyzed and its incorporation as an additional type of uncertainty in the suggested methodology is investigated, in order to enable the assessment of optimal water allocation for hydrologic and socio-economic scenarios based both on historical data and projected climate change conditions. For this purpose, stochastic simulation analysis for a part of the Alfeios river system is undertaken, testing various stochastic models from simple stationary ones (AR and ARMA), Thomas-Fiering, ARIMA as well as more sophisticated and

  15. Regression study of environmental quality objectives for soil, fresh water, and marine water, derived independently.

    PubMed

    Vega, M M; Urzelai, A; Angulo, E

    1997-12-01

    A regression study among environmental quality objectives on soil, marine and fresh water is studied, considering toxicity data on ecological representative species of invertebrates. The study was carried out by comparing VIE-C values, as defined by E. Angulo and A. Urzelai (1994, in Plan Director para la Protección del Suelo. Calidad del Suelo. Valores Indicativos de Evaluacion, pp. 121-184. IHOBE, Bilbao). To derive these VIE-C values, no-observed-effect concentrations from chronic single-species assays that consider relevant parameters in population dynamics are used. The calculations follow the method of N. M. van Straalen and C.A.J. Denneman (1989, Ecotoxicol. Environ. Saf. 18, 241-251). Equations relating long-term toxicity data of fresh/marine waters, soil/marine water, and soil/fresh water for five metals (Cd, Cu, Hg, Pb, and Zn) are calculated, indicating good correlation between environments: 0.85, 0.78, and 0.89, respectively. On the basis of these results this approach may be useful to obtain soil quality criteria values from other environmental compartments, when soil data are not available.

  16. Modeling fresh water lens damage and recovery on atolls after storm-wave washover.

    PubMed

    Chui, Ting Fong May; Terry, James P

    2012-01-01

    The principal natural source of fresh water on scattered coral atolls throughout the tropical Pacific Ocean is thin unconfined groundwater lenses within islet substrates. Although there are many threats to the viability of atoll fresh water lenses, salinization caused by large storm waves washing over individual atoll islets is poorly understood. In this study, a mathematical modeling approach is used to examine the immediate responses, longer-term behavior, and subsequent (partial) recovery of a Pacific atoll fresh water lens after saline damage caused by cyclone-generated wave washover under different scenarios. Important findings include: (1) the saline plume formed by a washover event mostly migrates downward first through the top coral sand and gravel substrate, but then exits the aquifer to the ocean laterally through the more permeable basement limestone; (2) a lower water table position before the washover event, rather than a longer duration of storm washover, causes more severe damage to the fresh water lens; (3) relatively fresher water can possibly be found as a preserved horizon in the deeper part of an aquifer after disturbance, especially if the fresh water lens extends into the limestone under normal conditions; (4) post-cyclone accumulation of sea water in the central depression (swamp) of an atoll islet prolongs the later stage of fresh water lens recovery.

  17. Mortality of experimentally descaled smolts of coho salmon (Oncorhynchus kisutch) in fresh and salt water

    USGS Publications Warehouse

    Bouck, Gerald R.; Smith, Stanley D.

    1979-01-01

    Removal of slime from 25% of the body caused no deaths among smolts of coho salmon in fresh water or in seawater (28‰). Removal of slime and scales from the same percentage of body area caused no deaths in fresh water, but 75% mortality within 10 days in seawater. The 10-day median tolerance limit was 10% scale removal immediately before the smolts entered seawater. Mortality was highest when the scales were removed from the area of the rib cage. Recovery of smolts in fresh water from a loss of scales that would be lethal in seawater occurred rapidly; 90% of the fish regained tolerance to seawater within 1 day.

  18. Biased monitoring of fresh water-salt water mixing zone in coastal aquifers.

    PubMed

    Shalev, Eyal; Lazar, Ariel; Wollman, Stuart; Kington, Shushanna; Yechieli, Yoseph; Gvirtzman, Haim

    2009-01-01

    In coastal aquifers, significant vertical hydraulic gradients are formed where fresh water and underlying salt water discharge together upward to the seafloor. Monitoring boreholes may act as "short circuits" along these vertical gradients, connecting between the higher and the lower hydraulic head zones. When a sea tide is introduced, the fluctuations of both the water table and the depth of the mixing zone are also biased due to this effect. This problem is intensified in places of long-screen monitoring boreholes, which are common in many places in the world. For example, all approximately 500 boreholes of the fresh water-salt water mixing zone in the coastal aquifer of Israel are installed with 10 to 50 m long screens. We present field measurements of these fluctuations, along with a three-dimensional numerical model. We find that the in-well fluctuation magnitude of the mixing zone is an order of magnitude larger than that in the porous media of the actual aquifer. The primary parameters that affect the magnitude of this bias are the anisotropy of the aquifer conductivity and the borehole hydraulic parameters. With no sea tide, borehole interference is higher for the anisotropic case because the vertical hydraulic gradients are high. When tides are introduced, the amplitude of the mixing zone fluctuation is higher for the isotropic case because the overall effective hydraulic conductivity is greater than the conductivity in the anisotropic case. In the aquifer, the fresh water-salt water mixing zone fluctuations are dampened, and tens of meters inland from the shoreline, the fluctuations are on the order of few centimeters.

  19. Evolutionary bottlenecks in brackish water habitats drive the colonization of fresh water by stingrays.

    PubMed

    Kirchhoff, K N; Hauffe, T; Stelbrink, B; Albrecht, C; Wilke, T

    2017-08-01

    Species richness in freshwater bony fishes depends on two main processes: the transition into and the diversification within freshwater habitats. In contrast to bony fishes, only few cartilaginous fishes, mostly stingrays (Myliobatoidei), were able to colonize fresh water. Respective transition processes have been mainly assessed from a physiological and morphological perspective, indicating that the freshwater lifestyle is strongly limited by the ability to perform osmoregulatory adaptations. However, the transition history and the effect of physiological constraints on the diversification in stingrays remain poorly understood. Herein, we estimated the geographic pathways of freshwater colonization and inferred the mode of habitat transitions. Further, we assessed habitat-related speciation rates in a time-calibrated phylogenetic framework to understand factors driving the transition of stingrays into and the diversification within fresh water. Using South American and Southeast Asian freshwater taxa as model organisms, we found one independent freshwater colonization event by stingrays in South America and at least three in Southeast Asia. We revealed that vicariant processes most likely caused freshwater transition during the time of major marine incursions. The habitat transition rates indicate that brackish water species switch preferably back into marine than forth into freshwater habitats. Moreover, our results showed significantly lower diversification rates in brackish water lineages, whereas freshwater and marine lineages exhibit similar rates. Thus, brackish water habitats may have functioned as evolutionary bottlenecks for the colonization of fresh water by stingrays, probably because of the higher variability of environmental conditions in brackish water. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  20. Clear salt water above sediment-laden fresh water: Interfacial instabilities

    NASA Astrophysics Data System (ADS)

    Schulte, B.; Konopliv, N.; Meiburg, E.

    2016-05-01

    The stability of an interface separating less dense, clear salt water above from more dense, sediment-laden fresh water below is explored via direct numerical simulations. We find that the destabilizing effects of double diffusion and particle settling amplify each other above the diffusive interface, whereas they tend to cancel each other below. For moderate settling velocities, plumes form both above and below the interface, whereas for large settling velocities plume formation below the interface is suppressed. We identify the dimensionless parameter that determines in which regime a given flow takes place, along with the critical value at which the transition between the regimes takes place.

  1. Clear salt water above sediment-laden fresh water: Interfacial instabilities

    NASA Astrophysics Data System (ADS)

    Konopliv, Nathan; Schulte, Bartho; Meiburg, Eckart

    2016-11-01

    The stability of an interface separating less dense, clear salt water above from more dense, sediment-laden fresh water below is explored via direct numerical simulations. We find that the destabilizing effects of double-diffusion and particle settling amplify each other above the diffusive interface, whereas they tend to cancel each other below. For moderate settling velocities, plumes form both above and below the interface, whereas for large settling velocities plume formation below the interface is suppressed. We identify the dimensionless parameter that determines in which regime a given flow takes place, along with the critical value at which the transition between the regimes takes place.

  2. Electromyogram as a measure of heavy metal toxicity in fresh water and salt water mussels

    SciTech Connect

    Kidder, G.W. III |; McCoy, A.A. |

    1996-02-01

    The response of bivalves to heavy metals and other toxins has usually been determined by observing valve position. Since mussels close their valves to avoid noxious stimuli, experimental delivery of chemicals ins uncertain. To obtain constant results plastic spacers can be employed to hold the valves apart. This obviates valve position as an index of response and some other method is required. Electromyography of intact mussels is one such index, giving a simple, effective, and quantitative measurement of activity. Experiments are reported in this article on the effects of added mercury on salt water and fresh water species.

  3. May 1984-April 1985 water budget of Reelfoot Lake with estimates of sediment inflow and concentrations of pesticides in bottom material in tributary streams; basic data report

    USGS Publications Warehouse

    Robbins, C.H.; Garrett, J.W.; Mulderink, D.M.

    1985-01-01

    This report contains hydrologic data collected at Reelfoot Lake, Tennessee from May 1, 1984, through April 30, 1985. Continuous streamflow data were collected at four sites on the three major tributaries to Reelfoot Lake and at one site on the lake outflow channel. Daily rainfall and lake-stage were each collected at two sites on the lake shore. Additionally, suspended-sediment samples were collected by automatic samplers and also manually during equipment maintenance visits at three of the four tributary inflow sites. At these three inflow sites, samples of stream-bottom material were collected at low flow once during the study period and were analyzed to determine the concentration of various pesticides. Periodic observations of ground-water levels were made at 30 wells in the Reelfoot Lake basin. Monitoring sites and types of data collected at each site are listed. (USGS)

  4. Real-time Control of sewer pumps by using ControlNEXT to smooth inflow at Waste Water Treatment Plant Garmerwolde

    NASA Astrophysics Data System (ADS)

    van Heeringen, Klaas-Jan; van Nooijen, Ronald; Kooij, Kees; Postma, Bokke

    2016-04-01

    The Garmerwolde waste water treatment plant (WWTP) in the Groningen area of the Netherlands, receives waste water from a large area. That waste water is collected from many sewer systems and transported to the WWTP through pressurized pipes. The supply of waste water to the WWTP is relatively low and very irregular during dry-weather conditions, resulting in a random pattern of flows. This irregularity is the effect of the local control of the pumps, where the pumps are individually operated as an on/off control based on the water levels in the connected sewer system. The influent may change from zero to high values in a few minutes. The treatment processes at the WWTP are negatively influenced by this irregularity, which ends in high costs for energy and use of chemicals. The ControlNEXT central control system is used to control the 5 largest pump stations, such that the total inflow at the WWTP becomes much smoother. This results in a reduction of operational costs of about 10%. The control algorithm determines whether the actual condition is dry or wet, based on real-time radar precipitation images and the rainfall forecast product HiRLAM. All actual data is also collected and validated, like water levels, pump operations and pump availability. This data management is done using Delft-FEWS. If the situation is identified as "wet", the sewer systems are emptied as far as possible to create maximum storage. If the situation is "dry" (and of course there is a dead band between dry and wet), the pumps are operated such that the total inflow into the WWTP is smoothed. This is done with a Greedy algorithm, developed by Delft University of Technology. The algorithm makes a plan for the next 24 hours (as the daily inflow has a typical daily pattern) and generally stores some water volume in the sewer systems during the day to be able to continue operations during the night. The pumps are controlled with a time step of 5 minutes, where ControlNEXT manages the

  5. Experimental drowning lung images on postmortem CT - Difference between sea water and fresh water.

    PubMed

    Hyodoh, Hideki; Terashima, Ryuji; Rokukawa, Masumi; Shimizu, Junya; Okazaki, Shunichiro; Mizuo, Keisuke; Watanabe, Satoshi

    2016-03-01

    Experimental drowning models were prepared to investigate the time-related course of lung changes using postmortem CT. This study was approved by our institutional animal ethics committee. Fifteen NZW rabbits (female fifteen, 2.6-4.3 (mean 3.3)kg) were divided into 3 groups: fresh water drowning (FRESH), sea water drowning (SEA), and sea water drowning with anterior chest compression (ACC). All individuals were examined by CT (Aquilion CX, Toshiba, Japan) on postmortem time course. The rabbit's head was submerged in a water bath for a total of 10 min. In ACC, cardiopulmonary resuscitation was performed for 2 min, additionally. The percentage of aerated lung volumes (%ALV=100 (aerated lung volume/total lung volume)) were statistically evaluated and the lung CT image patterns and pleural fluid appearance time were investigated. All lungs had decreased their %ALV within 24h, and there were no statistical differences in and among the 3 groups. After 36 h, %ALV tended to increase in all groups, and only ACC presented a statistical difference between 1h and 36 h (p<0.005). On postmortem lung CT, all lungs presented ground-glass opacity with interstitial thickening spread pattern (100%) and no pattern change during the follow-up period. After presenting pleural space fluid collection, the %ALV tended to increase. There were no differences among FRESH, SEA, and ACC in %ALV within 24h. Only ground-glass opacity could be detected on postmortem lung CT, experimentally. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Impact of eustatic sea level changes on the salt-water fresh-water interface in coastal ground waters

    NASA Astrophysics Data System (ADS)

    Riedel, Thomas; Lettmann, Karsten; Brumsack, Hans-Jürgen

    2010-05-01

    During the Holocene sea level rise has been inundating former glacial to inter-glacial deposits at the North German coast some of which are in use for municipal drinking water abstraction. Sea water intrusion into these sediments represents a serious threat to the coastal freshwater resources. To date, mechanisms and timing of salt water intrusion have not been explored. Interstitial waters from two drilling cores recovered about 3 km offshore the coastline of Northern Germany now offer the possibility of investigating the origin and possible age of the sea water intrusion. The chloride inventory shows that the sea-water fresh-water interface in the subsurface is currently not in equilibrium with the position of todaýs coastline. Furthermore, the shape of the chloride depth profile suggests that at least one regression must have intermitted the Holocene transgression. Based on these findings we conducted a transient numerical simulation to elucidate the impact of eustatic sea level changes on the salt-water fresh-water distribution within the subsurface of coastal regions. We applied a modified Henry model with an inclined surface and forced by a dynamic sea level. The results show that salt fronts in the subsurface follow the coastline during transgressions and promote a fast salinization of the model aquifer. A regression immediately leads to the freshening of surface sediments via the replacement of saline and brackish waters with meteoric waters, while flushing of deeper parts of the model aquifer with fresh-water was significantly slower. Although the coastline has moved seaward saline ground waters remained at depth because ground water velocities are slower and density-driven recirculation of sea water constantly resupplies salt water. The results indicate that the shape of the salt-water fresh-water interface in coastal aquifers may strongly be affected by eustatic sea level changes. They also provide evidence that man-made fixation of the coast line by

  7. Estimation of water turnover rates of captive West Indian manatees (Trichechus manatus) held in fresh and salt water

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Worthy, G. A.; Byers, F. M.

    1999-01-01

    The ability of West Indian manatees (Trichechus manatus) to move between fresh and salt water raises the question of whether manatees drink salt water. Water turnover rates were estimated in captive West Indian manatees using the deuterium oxide dilution technique. Rates were quantified in animals using four experimental treatments: (1) held in fresh water and fed lettuce (N=4), (2) held in salt water and fed lettuce (N=2), (3) acutely exposed to salt water and fed lettuce (N=4), and (4) chronically exposed to salt water with limited access to fresh water and fed sea grass (N=5). Animals held in fresh water had the highest turnover rates (145+/-12 ml kg-1 day-1) (mean +/- s.e.m.). Animals acutely exposed to salt water decreased their turnover rate significantly when moved into salt water (from 124+/-15 to 65+/-15 ml kg-1 day-1) and subsequently increased their turnover rate upon re-entry to fresh water (146+/-19 ml kg-1 day-1). Manatees chronically exposed to salt water had significantly lower turnover rates (21+/-3 ml kg-1 day-1) compared with animals held in salt water and fed lettuce (45+/-3 ml kg-1 day-1). Manatees chronically exposed to salt water and fed sea grass had very low turnover rates compared with manatees held in salt water and fed lettuce, which is consistent with a lack of mariposia. Manatees in fresh water drank large volumes of water, which may make them susceptible to hyponatremia if access to a source of Na+ is not provided.

  8. Estimation of water turnover rates of captive West Indian manatees (Trichechus manatus) held in fresh and salt water

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Worthy, G. A.; Byers, F. M.

    1999-01-01

    The ability of West Indian manatees (Trichechus manatus) to move between fresh and salt water raises the question of whether manatees drink salt water. Water turnover rates were estimated in captive West Indian manatees using the deuterium oxide dilution technique. Rates were quantified in animals using four experimental treatments: (1) held in fresh water and fed lettuce (N=4), (2) held in salt water and fed lettuce (N=2), (3) acutely exposed to salt water and fed lettuce (N=4), and (4) chronically exposed to salt water with limited access to fresh water and fed sea grass (N=5). Animals held in fresh water had the highest turnover rates (145+/-12 ml kg-1 day-1) (mean +/- s.e.m.). Animals acutely exposed to salt water decreased their turnover rate significantly when moved into salt water (from 124+/-15 to 65+/-15 ml kg-1 day-1) and subsequently increased their turnover rate upon re-entry to fresh water (146+/-19 ml kg-1 day-1). Manatees chronically exposed to salt water had significantly lower turnover rates (21+/-3 ml kg-1 day-1) compared with animals held in salt water and fed lettuce (45+/-3 ml kg-1 day-1). Manatees chronically exposed to salt water and fed sea grass had very low turnover rates compared with manatees held in salt water and fed lettuce, which is consistent with a lack of mariposia. Manatees in fresh water drank large volumes of water, which may make them susceptible to hyponatremia if access to a source of Na+ is not provided.

  9. Estimation of water turnover rates of captive West Indian manatees (Trichechus manatus) held in fresh and salt water.

    PubMed

    Ortiz, R M; Worthy, G A; Byers, F M

    1999-01-01

    The ability of West Indian manatees (Trichechus manatus) to move between fresh and salt water raises the question of whether manatees drink salt water. Water turnover rates were estimated in captive West Indian manatees using the deuterium oxide dilution technique. Rates were quantified in animals using four experimental treatments: (1) held in fresh water and fed lettuce (N=4), (2) held in salt water and fed lettuce (N=2), (3) acutely exposed to salt water and fed lettuce (N=4), and (4) chronically exposed to salt water with limited access to fresh water and fed sea grass (N=5). Animals held in fresh water had the highest turnover rates (145+/-12 ml kg-1 day-1) (mean +/- s.e.m.). Animals acutely exposed to salt water decreased their turnover rate significantly when moved into salt water (from 124+/-15 to 65+/-15 ml kg-1 day-1) and subsequently increased their turnover rate upon re-entry to fresh water (146+/-19 ml kg-1 day-1). Manatees chronically exposed to salt water had significantly lower turnover rates (21+/-3 ml kg-1 day-1) compared with animals held in salt water and fed lettuce (45+/-3 ml kg-1 day-1). Manatees chronically exposed to salt water and fed sea grass had very low turnover rates compared with manatees held in salt water and fed lettuce, which is consistent with a lack of mariposia. Manatees in fresh water drank large volumes of water, which may make them susceptible to hyponatremia if access to a source of Na+ is not provided.

  10. Groundwater flow cycling between a submarine spring and an inland fresh water spring.

    PubMed

    Davis, J Hal; Verdi, Richard

    2014-01-01

    Spring Creek Springs and Wakulla Springs are large first magnitude springs that derive water from the Upper Floridan Aquifer. The submarine Spring Creek Springs are located in a marine estuary and Wakulla Springs are located 18 km inland. Wakulla Springs has had a consistent increase in flow from the 1930s to the present. This increase is probably due to the rising sea level, which puts additional pressure head on the submarine Spring Creek Springs, reducing its fresh water flow and increasing flows in Wakulla Springs. To improve understanding of the complex relations between these springs, flow and salinity data were collected from June 25, 2007 to June 30, 2010. The flow in Spring Creek Springs was most sensitive to rainfall and salt water intrusion, and the flow in Wakulla Springs was most sensitive to rainfall and the flow in Spring Creek Springs. Flows from the springs were found to be connected, and composed of three repeating phases in a karst spring flow cycle: Phase 1 occurred during low rainfall periods and was characterized by salt water backflow into the Spring Creek Springs caves. The higher density salt water blocked fresh water flow and resulted in a higher equivalent fresh water head in Spring Creek Springs than in Wakulla Springs. The blocked fresh water was diverted to Wakulla Springs, approximately doubling its flow. Phase 2 occurred when heavy rainfall resulted in temporarily high creek flows to nearby sinkholes that purged the salt water from the Spring Creek Springs caves. Phase 3 occurred after streams returned to base flow. The Spring Creek Springs caves retained a lower equivalent fresh water head than Wakulla Springs, causing them to flow large amounts of fresh water while Wakulla Springs flow was reduced by about half. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  11. Groundwater flow cycling between a submarine spring and an inland fresh water spring

    USGS Publications Warehouse

    Davis, J. Hal; Verdi, Richard

    2014-01-01

    Spring Creek Springs and Wakulla Springs are large first magnitude springs that derive water from the Upper Floridan Aquifer. The submarine Spring Creek Springs are located in a marine estuary and Wakulla Springs are located 18 km inland. Wakulla Springs has had a consistent increase in flow from the 1930s to the present. This increase is probably due to the rising sea level, which puts additional pressure head on the submarine Spring Creek Springs, reducing its fresh water flow and increasing flows in Wakulla Springs. To improve understanding of the complex relations between these springs, flow and salinity data were collected from June 25, 2007 to June 30, 2010. The flow in Spring Creek Springs was most sensitive to rainfall and salt water intrusion, and the flow in Wakulla Springs was most sensitive to rainfall and the flow in Spring Creek Springs. Flows from the springs were found to be connected, and composed of three repeating phases in a karst spring flow cycle: Phase 1 occurred during low rainfall periods and was characterized by salt water backflow into the Spring Creek Springs caves. The higher density salt water blocked fresh water flow and resulted in a higher equivalent fresh water head in Spring Creek Springs than in Wakulla Springs. The blocked fresh water was diverted to Wakulla Springs, approximately doubling its flow. Phase 2 occurred when heavy rainfall resulted in temporarily high creek flows to nearby sinkholes that purged the salt water from the Spring Creek Springs caves. Phase 3 occurred after streams returned to base flow. The Spring Creek Springs caves retained a lower equivalent fresh water head than Wakulla Springs, causing them to flow large amounts of fresh water while Wakulla Springs flow was reduced by about half.

  12. Methicillin-resistant Staphylococcus aureus from Northwest Marine and Fresh Water Recreational Beaches

    PubMed Central

    Levin-Edens, Emily; Soge, Olusegun O.; No, David; Stiffarm, Amy; Meschke, J. Scott; Roberts, Marilyn C.

    2011-01-01

    The aim of the study was to determine the spatial distribution of methicillin-resistant Staphylococcus aureus [MRSA] at two marine and one fresh water recreational beaches in the Seattle area. Fifty-six marine water, 144 fresh water, and 96 sand samples were collected from June through August 2010. Isolates were biochemically verified as MRSA. Staphylococcal cassette chromosome mec (SCCmec) typing, multilocus sequence typing [MLST], pulse field gel electrophoresis [PFGE] and the presence of other antibiotic resistance genes were determined. Twenty-two fresh water [15.3%; n = 144], one dry sand [1.9%; n = 53], six wet sand [14%; n = 43], and 2 marine water samples [3.6%; n = 56] were MRSA positive. Of the 27 fresh water stream sites sampled multiple times, 37% of the sites were positive for MRSA and/or S. aureus ≥ 2 times. Twenty-one (67.7%) of 31 MRSA were SCCmec type IV, fifteen (48.4%) of the isolates had MLST types not previously associated with humans, and 29 (93.5%) of the isolates carried other antibiotic resistance genes. This study is the first to report and characterize repeated MRSA positive samples from fresh water drainages and creeks surrounding popular recreational beaches. PMID:22092827

  13. Fresh-water cementation of a 1,000-year-old oolite

    USGS Publications Warehouse

    Halley, R. B.; Harris, P. M.

    1979-01-01

    Calcite cementation of aragonite ooid sand is producing oolite on Joulters Cays, Bahamas. During the last 1,000 years, calcite cement has formed at an average rate of between 27 and 55 cm3 /m3 /yr and is derived from dissolution of ooid aragonite in fresh water. The dissolution-reprecipitation of carbonate minerals in the aquifer results in ground waters of unusually high Sr content. Sea water and mixtures of fresh and sea water appear to inhibit cementation. A pronounced cement fabric change occurs across the water table and has produced an obvious petrographic record of fresh-water diagenesis. Above the water table, cement is typically near grain contact positions, where water is held by capillarity; below the water table, cement is more randomly distributed around grains. At the water table a transition zone, 1 meter thick, marks the boundary between cement textures. No porosity reduction is associated with cementation; calcite cement precipitation is apparently compensated by an equal or greater amount of aragonite dissolution in the interval undergoing cementation. Permeability is more variable above the water table than below it, reflecting early channelling of flow patterns in the vadose zone. Effective permeability below the water table is one to two orders of magnitude higher than above the water table because of entrained gas in the vadose zone. This permeability difference promotes preservation of unstable minerals above the water table and continued diagenetic alteration below the water table.

  14. Water stress and crop load effects on fruit fresh and dry weights in peach (Prunus persica).

    PubMed

    Berman, M E; DeJong, T M

    1996-10-01

    Effects of water stress on fruit fresh and dry weights were investigated in peach trees, Prunus persica (L.) Batsch., with varying crop loads: light, moderate and heavy. In well-watered controls, tree water status was independent of crop load. In trees receiving reduced irrigation, the degree of water stress increased with increasing crop load. Water stress induced fruit fresh weight reductions at all crop loads. Fruit dry weight was not reduced by water stress in trees having light to moderate crop loads, indicating that the degree of water stress imposed did not affect the dry weight sink strength of fruit. Water-stressed trees with heavy crop loads had significantly reduced fruit dry weights, which were likely due to carbohydrate source limitations resulting from large crop carbon demands and water stress limitations on photosynthesis.

  15. Heat and fresh water transport by eddies into the Gulf of Alaska

    NASA Astrophysics Data System (ADS)

    Crawford, William R.

    2005-04-01

    Anticyclonic mesoscale eddies form in winter along the continental margin of Canada and Southeast Alaska between the latitudes of 51N and 60N and drift westward into the Gulf of Alaska, carrying warmer, fresher water away from the continental margin. Detailed measurements of temperature and salinity between 1995 and 2001 were examined to determine the amount of heat and fresh water transported seaward by several eddies that formed west of the Queen Charlotte Islands. Eddies formed in a typical winter carry about 30×10 18 J of heat into the gulf, which is about 35% to 60% of the heat transported northward each winter along the continental margin toward this region. The observed range of eddy heat transport is 10 19 to 10 20 J. Largest observed eddy heat transport coincided with increased northward heat flow along the continental margin during the El Niño winter of 1997/1998. Fresh-water volume was determined by evaluating the amount of fresh water required to reduce the salinity from a reference level to that observed in eddies. This volume varied from 0 to 70 km 3, and was largest during the 1997/1998 El Niño winter. Eddies formed in a typical winter transport 50 km 3 of fresh water seaward, which is about 15% of the estimated fresh-water input to the continental margin in winter between the Columbia River and 54N attributed to local runoff, plus direct rainfall and flow in major rivers.

  16. Infections Acquired via Fresh Water: From Lakes to Hot Tubs.

    PubMed

    Ayi, Bertha

    2015-12-01

    This chapter is unique in its focus on infections that are acquired in water. For those who like to swim and spend time in water parks and pools, the exposure to water and therefore the risk of infection is higher. Recreational water illnesses are illnesses related to recreation in water. Of these recreational water illnesses, infections are the most common because water laden with microorganisms or contaminated by human activity gains access to healthy tissue through the skin and body orifices. Infection occurs by inhalation, ingestion, or direct invasion of the respiratory and gastrointestinal tract. Gastrointestinal infections are the most common. This chapter discusses skin and soft tissue infections, ocular infections, urinary tract infections, pulmonary infections, central nervous system infections, and disseminated infections that can occur as people come into contact with natural nonmarine water bodies as well as manmade aquatic environments. Most of these infections are mild but can occasionally be life threatening. There is a focus on the latest methods to treat these infections. Pseudomonas aeruginosa is a very common pathogen in water. The chapter discusses P. aeruginosa dermatitis at length and also looks at keratitis and pneumonia caused by this organism. The chapter also discusses the latest treatments for primary amoebic meningoencephalitis, a severe life-threatening illness with a high mortality, caused by Naegleria fowleri. Finally, there is an in-depth discussion of the notorious gastrointestinal illnesses such as norovirus and Cryptosporidium parvum that can affect large numbers of people at a time.

  17. Simulation and evaluation of pollution load reduction scenarios for water environmental management: a case study of inflow river of Taihu Lake, China.

    PubMed

    Zhang, Ruibin; Qian, Xin; Zhu, Wenting; Gao, Hailong; Hu, Wei; Wang, Jinhua

    2014-09-09

    In the beginning of the 21st century, the deterioration of water quality in Taihu Lake, China, has caused widespread concern. The primary source of pollution in Taihu Lake is river inflows. Effective pollution load reduction scenarios need to be implemented in these rivers in order to improve the water quality of Taihu Lake. It is important to select appropriate pollution load reduction scenarios for achieving particular goals. The aim of this study was to facilitate the selection of appropriate scenarios. The QUAL2K model for river water quality was used to simulate the effects of a range of pollution load reduction scenarios in the Wujin River, which is one of the major inflow rivers of Taihu Lake. The model was calibrated for the year 2010 and validated for the year 2011. Various pollution load reduction scenarios were assessed using an analytic hierarchy process, and increasing rates of evaluation indicators were predicted using the Delphi method. The results showed that control of pollution from the source is the optimal method for pollution prevention and control, and the method of "Treatment after Pollution" has bad environmental, social and ecological effects. The method applied in this study can assist for environmental managers to select suitable pollution load reduction scenarios for achieving various objectives.

  18. Simulation and Evaluation of Pollution Load Reduction Scenarios for Water Environmental Management: A Case Study of Inflow River of Taihu Lake, China

    PubMed Central

    Zhang, Ruibin; Qian, Xin; Zhu, Wenting; Gao, Hailong; Hu, Wei; Wang, Jinhua

    2014-01-01

    In the beginning of the 21st century, the deterioration of water quality in Taihu Lake, China, has caused widespread concern. The primary source of pollution in Taihu Lake is river inflows. Effective pollution load reduction scenarios need to be implemented in these rivers in order to improve the water quality of Taihu Lake. It is important to select appropriate pollution load reduction scenarios for achieving particular goals. The aim of this study was to facilitate the selection of appropriate scenarios. The QUAL2K model for river water quality was used to simulate the effects of a range of pollution load reduction scenarios in the Wujin River, which is one of the major inflow rivers of Taihu Lake. The model was calibrated for the year 2010 and validated for the year 2011. Various pollution load reduction scenarios were assessed using an analytic hierarchy process, and increasing rates of evaluation indicators were predicted using the Delphi method. The results showed that control of pollution from the source is the optimal method for pollution prevention and control, and the method of “Treatment after Pollution” has bad environmental, social and ecological effects. The method applied in this study can assist for environmental managers to select suitable pollution load reduction scenarios for achieving various objectives. PMID:25207492

  19. Acid precipitation: Effects on fresh water ecosystems. (Latest citations from the Life Sciences Collection database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the effects of acidification on fresh water ecosystems. Algae and diatom distribution, survival and reproduction rates of specific fish species under acid lake conditions, and tolerance to stress caused by acidic conditions in fresh water ecosystems are studied. Effects of water pH on trace metal toxicity to fresh water organisms are briefly considered. Control and reduction of acidification are excluded from this bibliography. (Contains 250 citations and includes a subject term index and title list.)

  20. Evaluation of the impact of hot water treatment on the sensory quality of fresh tomatoes

    USDA-ARS?s Scientific Manuscript database

    Minimizing the effects of chilling injury during shelf-life is important for maintaining the sensory quality of fresh tomato fruit. Postharvest hot water treatments within certain limits of exposure time and water temperature have been shown to increase the resistance of tomatoes to chilling injury....

  1. Assessment and speciation of chlorine demand in fresh-cut produce wash water

    USDA-ARS?s Scientific Manuscript database

    Production of high quality, fresh-cut produce is a key driver for the produce industry. A critical area of concern is the chlorinated wash water used during post-harvest processing in large industrial processing facilities. Predominantly using a batch process, wash water is recycled over 8hr shift...

  2. COSOLVENT EFFECTS ON PHENANTHRENE SORPTION-DESORPTION ON A FRESH-WATER SEDIMENT

    EPA Science Inventory

    This study evaluated the effects of the water-miscible cosolvent methanol on the sorption-desorption of phenanthrene by the natural organic matter (NOM) of a fresh-water sediment. A biphasic pattern was observed in the relationship between the log of the carbon-normalized sorpti...

  3. Competency-Based Curriculum for Prevocational Exploration. Marine/Fresh Water.

    ERIC Educational Resources Information Center

    Reese, Clara C.

    This competency-based curriculum is intended to help teachers of prevocational career exploration courses in West Virginia to present information about marine/fresh water occupations. The document is organized into five units: fisheries, life sciences, marine life cultivation, research, and water vehicle operation. Each unit consists of five to 15…

  4. Competency-Based Curriculum for Prevocational Exploration. Marine/Fresh Water.

    ERIC Educational Resources Information Center

    Reese, Clara C.

    This competency-based curriculum is intended to help teachers of prevocational career exploration courses in West Virginia to present information about marine/fresh water occupations. The document is organized into five units: fisheries, life sciences, marine life cultivation, research, and water vehicle operation. Each unit consists of five to 15…

  5. The effect of atrazine on Atlantic salmon (Salmo salar) smolts in fresh water and after sea water transfer.

    PubMed

    Waring, Colin P; Moore, Andrew

    2004-01-07

    Groups of Atlantic salmon smolts were exposed to low levels of the pesticide atrazine (2-chloro-4-ethylamino-6-isopropylamino-S-triazine) (0-22.7microgl(-1)) in fresh water and the physiological effects of exposure were measured. Further experiments exposed salmon smolts to similar levels of atrazine in fresh water, and then exposed them to full strength sea water. Atrazine in fresh water resulted in a significant reduction in gill Na(+)K(+)ATPase activity at concentrations of 2.0, 5.0 and 10.0microgl(-1). There were few other physiological changes in the smolts except for slightly elevated plasma cortisol concentrations and monovalent ion concentrations at and above 5.0microgl(-1). However, a sea water challenge caused mortalities in smolts that had been pre-exposed to atrazine in fresh water at concentrations of 1.0, 2.0, 5.0, 10.0 and 22.7microgl(-1). Moreover, surviving fish showed signs of major physiological stress: elevated plasma cortisol, thyroxine, osmolality, and monovalent ion concentrations. However, atrazine exposure had no effect on muscle or plasma water contents. The data suggests that exposure of salmon smolts to atrazine in fresh water may compromise their physiological capabilities to survive in saline conditions.

  6. Corrosion of stainless steel piping in high manganese fresh water

    SciTech Connect

    Avery, R.E.; Lutey, R.W.; Musick, J.; Pinnow, K.E.; Tuthill, A.H.

    1996-09-01

    A potable water treatment plant, designed to reduce manganese and iron in well water, experienced leaks in the 16 in. (406 mm) raw water headers about nine months after startup. The material, type 304 (UNS 30403) stainless steel, was purchased to American Society of Testing Materials specification A 778, with additional stipulations governing internal finish, the use of filler metal, and pickling for scale removal. Laboratory screenings of deposits for bacteria revealed some potentially additive corrosive effects from microbial action. However, the correlation of corrosion with the presence or absence of heat tint in the heat-affected zone of the circumferential welds prevailed as a primary cause of the corrosion observed beneath an adherent manganese-iron deposit in a low chloride, high manganese, raw water.

  7. Microbial extracellular polymeric substances (EPS) in fresh water sediments.

    PubMed

    Gerbersdorf, Sabine Ulrike; Westrich, Bernhard; Paterson, David M

    2009-08-01

    Microbially produced extracellular polymeric substances (EPS) have been linked with many important ecological functions in natural sediments; yet, most information has been derived from marine systems. The present paper is the first comprehensive study on EPS (i.e., carbohydrates and proteins) dynamics in riverine sediments addressing spatial (six reservoirs and four groyne fields across three European rivers), temporal (all seasons in 2003-2005), and vertical (over a 50-cm sediment depth transect) pattern. The variation in hydrodynamic regime found in the reservoirs and groyne fields was reflected in the biomass and composition of the benthic microorganisms that produce EPS. The microphytobenthic communities consisted mainly of diatoms and a higher algal biomass (up to 248 microg g(-1) dry weight, DW) seemed to be indicative for higher amounts of secreted colloidal carbohydrates. Consequently, the model proposed by Underwood and Smith (1998) for the relation chlorophyll-colloidal carbohydrates was also applicable for upper riverine sediment layers. The close relation between algal biomass and bacterial cell counts (10(8)-10(9) cells g(-1) DW) supports the idea of bacterial use of the secreted EPS. However, the data also suggest a contribution to the EPS pool through bacterial secretion of proteins/extracellular enzymes and possibly carbohydrates. Over depth, the relationships between microorganisms and EPS became increasingly decoupled along with increasing ratios of bound (refractory) to colloidal (labile) EPS. These data suggest fresh production of polymeric substances in upper sediment layers and mainly accumulation of refractory, biodegraded material in deeper layers. The high contents of EPS colloidal and bound carbohydrates (0.1-1.8 and 1.3-6.7 mg g(-1) DW, respectively) and EPS proteins (0.4-12.9 mg g(-1) DW) at the freshwater study sites might indicate an important role in sediment ecology.

  8. Full STR profile of a 67-year-old bone found in a fresh water lake.

    PubMed

    Courts, Cornelius; Madea, Burkhard

    2011-01-01

    DNA extraction from and DNA typing of fresh water-exposed aged bone specimens poses a challenging task and is not very well examined. This study presents a new method to extract typable DNA from such problematic bone specimens. The procedure comprises low-heat drilling and cryogrinding, mild lysis conditions, and silica-column-based DNA cleaning. DNA quantity is assessed by quantitative PCR prior to short tandem repeat (STR) amplification. The procedure was employed with a 67-year-old tibia bone fragment recovered from a fresh water lake and succeeded to produce a full STR profile using the MPX-SP1 and MPX-SP2 mini-STR kits and a partial profile with 12 successfully amplified STRs using the Identifiler STR kit. The new method for the extraction of DNA from aged fresh water-exposed bone specimens presented herein was successfully applied to prepare DNA of sufficient quality and quantity to generate a full STR profile.

  9. Perspectives on Temperature in the Pacific Northwest's Fresh Waters

    SciTech Connect

    Coutant, C.C.

    1999-06-01

    This report provides a perspective on environmental water temperatures in the Pacific Northwest as they relate to the establishment of water temperature standards by the state and their review by the US Environmental Protection Agency. It is a companion to other detailed reviews of the literature on thermal effects on organisms important to the region. Many factors, both natural and anthropogenic, affect water temperatures in the region. Different environmental zones have characteristic temperatures and mechanisms that affect them. There are specific biotic adaptations to environmental temperatures. Life-cycle strategies of salmonids, in particular, are attuned to annual temperature patterns. Physiological and behavioral requirements on key species form the basis of present water temperature criteria, but may need to be augmented with more concern for environmental settings. There are many issues in the setting of standards, and these are discussed. There are also issues in compliance. Alternative temperature-regulating mechanisms are discussed, as are examples of actions to control water temperatures in the environment. Standards-setting is a social process for which this report should provide background and outline options, alternatives, limitations, and other points for discussion by those in the region.

  10. Cultivation of macroscopic marine algae and fresh water aquatic weeds

    SciTech Connect

    Ryther, J.H.

    1982-02-01

    The ORCA clone of the red seaweed Gracilaria tikvahiae has been in culture continuously for over two years. Yield for the past year has averaged 12 g ash-free dry wt/m/sup 2/ .day (17.5 t/a.y) in suspended 2600-1 aluminum tank cultures with four exchanges of enriched seawater per day and continuous aeration. Yields from nonintensive pond-bottom culture, similar to commercial Gracilaria culture methods in Taiwan, averaged 3 g afdw/m/sup 2/.day in preliminary experiments. Rope and spray cultures were not successful. Yields of water hyacinths from March 1978 to March 1979 averaged 25 g afdw/m/sup 2/.day (37 t/a.y). Season, nutrient availability (form and quantity) and stand density were found to affect the relative proportions of structural and nonstructural tissue in water hyacinths and thereby significantly affect digestibility of and methane production by the plants. Pennywort (Hydrocotyle) grew poorly in winter and its annual yield averaged only one-third that of water hyacinth. Water lettuce (Pistia) appears more comparable to hyacinths in preliminary studies and its yields will be monitored throughout a complete year. Stable, continuous anaerobic digestion of both water hyacinths and Gracilaria has been maintained with an average gas production from both species of 0.4 1/g volatile solids at 60% methane.

  11. Formation of trichloromethane in chlorinated water and fresh-cut produce and as a result of reacting with citric acid

    USDA-ARS?s Scientific Manuscript database

    Chlorine (sodium hypochlorite) is commonly used by the fresh produce industry to sanitize wash water, fresh and fresh-cut fruits and vegetables. However, possible formation of harmful chlorine by-products is a concern. The objectives of this study were to compare chlorine and chlorine dioxide in t...

  12. Survival of Candida albicans in tropical marine and fresh waters.

    PubMed Central

    Valdes-Collazo, L; Schultz, A J; Hazen, T C

    1987-01-01

    A survey of Candida albicans indicated that the organism was present at all sites sampled in a rain forest stream and in near-shore coastal waters of Puerto Rico. In the rain forest watershed no relationship existed between densities of fecal coliforms and densities of C. albicans. At two pristine sites in the rain forest watershed both C. albicans and Escherichia coli survived in diffusion chambers for extended periods of time. In near-shore coastal waters C. albicans and E. coli survival times in diffusion chambers were enhanced by effluent from a rum distillery. The rum distillery effluent had a greater effect on E. coli than on C. albicans survival in the diffusion chambers. These studies show that neither E. coli nor C. albicans organisms are good indicators of recent fecal contamination in tropical waters. It further demonstrates that pristine freshwater environments and marine waters receiving organic loading in the tropics can support densities of C. albicans which may be a health hazard. Images PMID:3310885

  13. A Primer on Fresh Water: The Environmental Citizenship Series.

    ERIC Educational Resources Information Center

    Environment Canada, Ottawa (Ontario).

    Water is the lifeblood of the environment as no organisms can survive without it. This reference booklet is designed to help people make environmentally responsible decisions. The primer is targeted at the general public (grade 8 to post-secondary) to be used by educators, communities and organizations as well as individuals, as part of a learning…

  14. Development of methods to measure virus inactivation in fresh waters.

    PubMed Central

    Ward, R L; Winston, P E

    1985-01-01

    This study concerns the identification and correction of deficiencies in methods used to measure inactivation rates of enteric viruses seeded into environmental waters. It was found that viable microorganisms in an environmental water sample increased greatly after addition of small amounts of nutrients normally present in the unpurified seed virus preparation. This burst of microbial growth was not observed after seeding the water with purified virus. The use of radioactively labeled poliovirus revealed that high percentages of virus particles, sometimes greater than 99%, were lost through adherence to containers, especially in less turbid waters. This effect was partially overcome by the use of polypropylene containers and by the absence of movement during incubation. Adherence to containers clearly demonstrated the need for labeled viruses to monitor losses in this type of study. Loss of viral infectivity in samples found to occur during freezing was avoided by addition of broth. Finally, microbial contamination of the cell cultures during infectivity assays was overcome by the use of gentamicin and increased concentrations of penicillin, streptomycin, and amphotericin B. PMID:3004328

  15. [Contamination of protozoa by enteroviruses in fresh water and sewages].

    PubMed

    Skachkov, M V; Al'misheva, A Sh; Plotnikov, A O; Nemtseva, N V; Skvortsov, V O

    2009-01-01

    To determine rate of infection of protozoa by enteroviruses to assess the potential role of protozoa as a natural reservoir of enteroviruses. The samples were collected from flowing and stagnant water reservoirs in Orenburg region in summer and autumn. The samples of sewages were taken in all stages of their treatment. Cultures of protozoa were isolated with micromanipulator equipped with micropipette, incubated on Pratt's medium at 25 degrees C and fed with Pseudomonas fluorescens culture. RNA of enteroviruses was detected by reverse transcription polymerase chain reaction (RT-PCR). Seventy-two protozoan species were found in Ural river, whereas 15 and 38 species were found in lakes and sewages respectively. Enteroviruses were detected by RT-PCR in 61.8% cultures of protozoa belonging to 23 species of flagellates, amoebae and ciliates isolated from natural water bodies undergoing anthropogenic impact as well as from sewages in all stages of their treatment. Predominant localization of enteroviruses in dominant taxons of protozoa (Paraphysomonas sp., Spumella sp., Petalomonas poosilla, Amoeba sp.) was noted. Obtained data confirm presence of enteroviruses in protozoa living both in flowing and stagnant recreation natural water bodies as well as in sewages and confirm the hypothesis of persistence of enteroviruses in protozoa and the reservoir role of the latter. Contingency of life cycles of viruses and protozoa allows to explain the seasonality of aseptic meningitis incidence caused by enteroviruses, which peaks in summer and autumn when protozoa massively multiply in water bodies.

  16. Developing the greatest Blue Economy: Water productivity, fresh water depletion, and virtual water trade in the Great Lakes basin

    NASA Astrophysics Data System (ADS)

    Mayer, A. S.; Ruddell, B. L.; Mubako, S. T.

    2016-12-01

    The Great Lakes basin hosts the world's most abundant surface fresh water reserve. Historically an industrial and natural resource powerhouse, the region has suffered economic stagnation in recent decades. Meanwhile, growing water resource scarcity around the world is creating pressure on water-intensive human activities. This situation creates the potential for the Great Lakes region to sustainably utilize its relative water wealth for economic benefit. We combine economic production and trade datasets with water consumption data and models of surface water depletion in the region. We find that, on average, the current economy does not create significant impacts on surface waters, but there is some risk that unregulated large water uses can create environmental flow impacts if they are developed in the wrong locations. Water uses drawing on deep groundwater or the Great Lakes themselves are unlikely to create a significant depletion, and discharge of groundwater withdrawals to surface waters offsets most surface water depletion. This relative abundance of surface water means that science-based management of large water uses to avoid accidentally creating "hotspots" is likely to be successful in avoiding future impacts, even if water use is significantly increased. Commercial water uses are the most productive, with thermoelectric, mining, and agricultural water uses in the lowest tier of water productivity. Surprisingly for such a water-abundant economy, the region is a net importer of water-derived goods and services. This, combined with the abundance of surface water, suggests that the region's water-based economy has room to grow in the 21st century.

  17. Developing the greatest Blue Economy: Water productivity, fresh water depletion, and virtual water trade in the Great Lakes basin

    NASA Astrophysics Data System (ADS)

    Mayer, Alex; Mubako, Stanley; Ruddell, Benjamin L.

    2016-06-01

    The Great Lakes basin hosts the world's most abundant surface fresh water reserve. Historically an industrial and natural resource powerhouse, the region has suffered economic stagnation in recent decades. Meanwhile, growing water resource scarcity around the world is creating pressure on water-intensive human activities. This situation creates the potential for the Great Lakes region to sustainably utilize its relative water wealth for economic benefit. We combine economic production and trade datasets with water consumption data and models of surface water depletion in the region. We find that, on average, the current economy does not create significant impacts on surface waters, but there is some risk that unregulated large water uses can create environmental flow impacts if they are developed in the wrong locations. Water uses drawing on deep groundwater or the Great Lakes themselves are unlikely to create a significant depletion, and discharge of groundwater withdrawals to surface waters offsets most surface water depletion. This relative abundance of surface water means that science-based management of large water uses to avoid accidentally creating "hotspots" is likely to be successful in avoiding future impacts, even if water use is significantly increased. Commercial water uses are the most productive, with thermoelectric, mining, and agricultural water uses in the lowest tier of water productivity. Surprisingly for such a water-abundant economy, the region is a net importer of water-derived goods and services. This, combined with the abundance of surface water, suggests that the region's water-based economy has room to grow in the 21st century.

  18. Preliminary observations on infection of brackish and fresh water fish by heterophyid encysted metacercariae in Egypt.

    PubMed

    Elsheikha, Hany M; Elshazly, Attef M

    2008-09-01

    The infection status with heterophyids in the second intermediate host fish obtained from brackish and fresh water resources in Dakahlia governorate, northern Egypt was investigated. Encysted metacercariae (EMC) in the fish species Mugil cephalus, Mugil capito, Mugil auratus, Tilapia nilotica, and Tilapia zilli from brackish water and T. nilotica and T. zilli from fresh water were isolated by artificial digestion method and identified by microscopic examination. Morphometric analysis of EMC isolated from these fishes identified seven phenotypically distinct groups. No significant morphologic differences were detected between EMC of the same group obtained from different fish species. The adult flukes recovered from seven groups of puppies separately infected with distinct EMC groups were compatible with seven species belong to six genera of Heterophyidae namely Heterophyes heterophyes, Heterophyes aequalis, Pygidiopsis genata, Haplorchis yokogawi, Prohemostomum vivax, Phagicola ascolonga, and Stictodora tridactyla. EMC of these seven heterophyid species were detected in all examined brackish water fishes. On the other hand, only EMC of P. genata, H. yokogawi, and P. ascolonga were detected in fresh water fishes, T. nilotica and T. zilli. These results indicate that heterophyid infections occur in brackish and fresh water fishes in northern Egypt, where the parasites are indigenous.

  19. Consumptive water use associated with food waste: case study of fresh mango in Australia

    NASA Astrophysics Data System (ADS)

    Ridoutt, B. G.; Juliano, P.; Sanguansri, P.; Sellahewa, J.

    2009-07-01

    In many parts of the world, freshwater is already a scarce and overexploited natural resource, raising concerns about global food security and damage to freshwater ecosystems. This situation is expected to intensify with the FAO estimating that world food production must double by 2050. Food chains must therefore become much more efficient in terms of consumptive water use. For the small and geographically well-defined Australian mango industry, having an average annual production of 44 692 t of marketable fresh fruit, the average virtual water content (sum of green, blue and gray water) at orchard gate was 2298 l kg-1. However, due to wastage in the distribution and consumption stages of the product life cycle, the average virtual water content of one kg of Australian-grown fresh mango consumed by an Australian household was 5218 l. This latter figure compares to an Australian-equivalent water footprint of 217 l kg-1, which is the volume of direct water use by an Australian household having an equivalent potential to contribute to water scarcity. Nationally, distribution and consumption waste in the food chain of Australian-grown fresh mango to Australian households represented an annual waste of 26.7 Gl of green water and 16.6 Gl of blue water. These findings suggest that interventions to reduce food chain waste will likely have as great or even greater impact on freshwater resource availability as other water use efficiency measures in agriculture and food production.

  20. Background nitrogen concentrations in fresh waters in Denmark

    NASA Astrophysics Data System (ADS)

    Windolf, Jørgen; Bøgestrand, Jens; Blicher-Mathiesen, Gitte; Kronvang, Brian

    2013-04-01

    Quantitative information on the background loading of nitrogen is important when establishing the pressure-impact pathway for Danish springs, streams, lakes and estuaries The background nitrogen loading thus determines present day lowest nitrogen loadings without influence from point sources and agriculture but includes present day atmospheric deposition of nitrogen compounds. We have mapped the background concentration of nitrogen in Danish soil water, springs and streams based on monitoring in one soil water station (1990-2010), 11 springs, 7 small streams draining undisturbed catchments (1990-2010) and 19 streams draining small undisturbed catchments (2004-11). The concentration of ammonium-N (NH4+) and organic N was found to be nearly constant within six major landscape types in Denmark, respectively, 0.05 mg ± 0.06 mg N L-1 and 0.53 mg ± 0.29 mg N L-1. On contrary, the concentration of nitrate-nitrite-N (NO3- + NO2-) was found to vary between 0.06-0.83 mg N L-1 within the six landscape types. We have also time series of background total nitrogen concentrations from 7 small undisturbed catchments covering the period 1990-2010. No significant trends have been observed for total nitrogen concentrations from these streams during the period 1990-2010. The measured average nitrate-N concentrations in streams has been modelled against dominant landscape geology and a 5x5 km grid map of Denmark showing background concentrations of nitrate-N and total N has been produced. This map has been used during the implementation of the EU Water Framework Directive as a baseline for estimating background nitrogen losses to surface waters in Denmark. Thus, the average annual background loss of total nitrogen amounts to 13,000 tonnes N or 20% of the total loading of nitrogen from the Danish land to sea during the period 2005-2009.

  1. Exploring the limits of the terrestrial fresh water cycle

    NASA Astrophysics Data System (ADS)

    van der Ent, Ruud; Wang-Erlandsson, Lan; Keys, Patrick; Savenije, Hubert

    2014-05-01

    Precipitation is the ultimate source of life on this planet: it makes our crops grow, provides drinking water, feeds rivers and replenishes groundwater aquifers. Climate modelling studies estimate changes in precipitation due to increased greenhouse gas emissions and climate impact studies use those estimates as input to their (hydrological) models to predict future water availability and societal impact. However, humans also significantly alter the land surface by, for example, deforestation and irrigation, which is not frequently taken into account in our climate studies. Here, we present an overview of several papers in the field of moisture recycling, published by our group, that show the extent to which terrestrial evaporation influences terrestrial precipitation. It is found that 38% of the terrestrial precipitation originates from terrestrial evaporation and that 58% of all terrestrial evaporation recycles, and return again as terrestrial precipitation. Knowing this, it is clear that evaporation is not necessary a loss to the hydrological cycle. We show that in some cases even transpiration during the dry season can act as a moisture source for a distant region. To assess the vulnerability of a region to local and remote land use changes we propose the concept of the precipitationshed, which maps out a region's precipitation sources. Our results are useful in mapping out possible land use change threats, but also opportunities to safeguard our water resources in the Anthropocene.

  2. Hygienic importance of increased barium content in some fresh waters.

    PubMed

    Havlík, B; Hanusová, J; Rálková, J

    1980-01-01

    In surface waters of the mining and processing areas of uranium ore there is an increased content of free and bound barium ions due to the use of barium salts for the treatment of waste and mine waters containing radium. In model experiments with the algae Ankistrodesmus falcatus, Chlorella kessleri and Scenedesmus obliquus, we studied the effect of Ba2+ on the accumulation of 226Ra. It was found that the accumulation of radium by algae is negatively influenced with barium concentrations higher than 1 mg.l-1. The accumulation of barium of organisms of primary production was studied using 133BaCl2. At a barium content in the medium of 4.0, 0.46 and 0.04 mu. l-1, the algae accumulated 30-60% of the added amount of barium during an exposure of 15 days. Biochemical analyses showed that barium is bound to the cellular membrane and to other components of the algal cell that cannot be extracted with water or alcohol.

  3. Production of Algal-based Biofuel from Non-fresh Water Sources

    NASA Astrophysics Data System (ADS)

    Sun, A. C.; Reno, M. D.

    2008-12-01

    A system dynamics model is developed to assess the availability and feasibility of non-traditional water sources from dairy wastewater, produced water from crude oil production and from coal-bed methane gas extraction for the production of algal-based biofuel. The conceptual framework is based on two locales within New Mexico, the San Juan basin in the northwest and the Permian basin in the southeast, where oil and gas drilling have increased considerably in the last ten years. The simulation framework contains an algal growth module, a dairy module, an oil production module, and a gas production module. Our preliminary investigation indicates a cyclical demand for non-fresh water due to the cyclical nature of algal biomass production and crop evapotranspiration. The wastewater from the dairy industry is not a feasible non-fresh water source because the agricultural water demand for cow's dry feed far exceeds the amount generated at the dairy. The uncertainty associated with the water demand for cow's dry matter intake is the greatest in this model. The oil and gas produced water, ignoring the quality, provides ample supply for water demand in algal biomass production. There remains work to address technical challenges associated with coupling the appropriate non-fresh water source to the local demand.

  4. Quantifying the Global Fresh Water Budget: Capabilities from Current and Future Satellite Sensors

    NASA Technical Reports Server (NTRS)

    Hildebrand, Peter; Zaitchik, Benjamin

    2007-01-01

    The global water cycle is complex and its components are difficult to measure, particularly at the global scales and with the precision needed for assessing climate impacts. Recent advances in satellite observational capabilities, however, are greatly improving our knowledge of the key terms in the fresh water flux budget. Many components of the of the global water budget, e.g. precipitation, atmospheric moisture profiles, soil moisture, snow cover, sea ice are now routinely measured globally using instruments on satellites such as TRMM, AQUA, TERRA, GRACE, and ICESat, as well as on operational satellites. New techniques, many using data assimilation approaches, are providing pathways toward measuring snow water equivalent, evapotranspiration, ground water, ice mass, as well as improving the measurement quality for other components of the global water budget. This paper evaluates these current and developing satellite capabilities to observe the global fresh water budget, then looks forward to evaluate the potential for improvements that may result from future space missions as detailed by the US Decadal Survey, and operational plans. Based on these analyses, and on the goal of improved knowledge of the global fresh water budget under the effects of climate change, we suggest some priorities for the future, based on new approaches that may provide the improved measurements and the analyses needed to understand and observe the potential speed-up of the global water cycle under the effects of climate change.

  5. Quantifying the Global Fresh Water Budget: Capabilities from Current and Future Satellite Sensors

    NASA Technical Reports Server (NTRS)

    Hildebrand, Peter; Zaitchik, Benjamin

    2007-01-01

    The global water cycle is complex and its components are difficult to measure, particularly at the global scales and with the precision needed for assessing climate impacts. Recent advances in satellite observational capabilities, however, are greatly improving our knowledge of the key terms in the fresh water flux budget. Many components of the of the global water budget, e.g. precipitation, atmospheric moisture profiles, soil moisture, snow cover, sea ice are now routinely measured globally using instruments on satellites such as TRMM, AQUA, TERRA, GRACE, and ICESat, as well as on operational satellites. New techniques, many using data assimilation approaches, are providing pathways toward measuring snow water equivalent, evapotranspiration, ground water, ice mass, as well as improving the measurement quality for other components of the global water budget. This paper evaluates these current and developing satellite capabilities to observe the global fresh water budget, then looks forward to evaluate the potential for improvements that may result from future space missions as detailed by the US Decadal Survey, and operational plans. Based on these analyses, and on the goal of improved knowledge of the global fresh water budget under the effects of climate change, we suggest some priorities for the future, based on new approaches that may provide the improved measurements and the analyses needed to understand and observe the potential speed-up of the global water cycle under the effects of climate change.

  6. The effects of river inflow and retention time on the spatial heterogeneity of chlorophyll and water-air CO2 fluxes in a tropical hydropower reservoir

    NASA Astrophysics Data System (ADS)

    Pacheco, F. S.; Soares, M. C. S.; Assireu, A. T.; Curtarelli, M. P.; Abril, G.; Stech, J. L.; Alvalá, P. C.; Ometto, J. P.

    2015-01-01

    Abundant research has been devoted to understanding the complexity of the biogeochemical and physical processes that are responsible for greenhouse gas (GHG) emissions from hydropower reservoirs. These systems may have spatially complex and heterogeneous GHG emissions due to flooded biomass, river inflows, primary production and dam operation. In this study, we investigated the relationships between the water-air CO2 fluxes and the phytoplanktonic biomass in the Funil Reservoir, which is an old, stratified tropical reservoir that exhibits intense phytoplankton blooms and a low partial pressure of CO2 (pCO2). Our results indicated that the seasonal and spatial variability of chlorophyll concentrations (Chl) and pCO2 in the Funil Reservoir are related more to changes in the river inflow over the year than to environmental factors such as air temperature and solar radiation. Field data and hydro-dynamic simulations revealed that river inflow contributes to increased heterogeneity during the dry season due to variations in the reservoir retention time and river temperature. Contradictory conclusions could be drawn if only temporal data collected near the dam were considered without spatial data to represent CO2 fluxes throughout the reservoir. During periods of high retention, the average CO2 fluxes were 10.3 mmol m-2 d-1 based on temporal data near the dam versus -7.2 mmol m-2 d-1 with spatial data from along the reservoir surface. In this case, the use of solely temporal data to calculate CO2 fluxes results in the reservoir acting as a CO2 source rather than a sink. This finding suggests that the lack of spatial data in reservoir C budget calculations can affect regional and global estimates. Our results support the idea that the Funil Reservoir is a dynamic system where the hydrodynamics represented by changes in the river inflow and retention time are potentially a more important force driving both the Chl and pCO2 spatial variability than the in-system ecological

  7. Energy from fresh and brackish water aquatic plants

    SciTech Connect

    Benemann, J.R.

    1981-01-01

    Aquatic plants can achieve relatively high biomass productivities when compared to terrestrial plants because they need not be water-stressed and can be optimally supplied with nutrients. Based on literature reports, productivities in southern US regions of about 40 to 60 t/ha-yr (dry weight basis) can be predicted for green algae or marsh plants and about 80 t/ha-yr for water hyacinth. Higher productivities may be possible in exceptionally favorable locations by assuming development of advanced cultivation technologies and genetic selection of improved strains. The lack of established cultivation systems and low-cost harvesting processes imposes great uncertainties on the cost of biomass production by aquatic plants. Three potentially practical aquatic biomass energy systems are chemicals production from microalgae, alcohol production from marsh plants, and methane production from water hyacinths. At present, aquatic plants are not being used commercially as a fuel source any place in the world. Nevertheless, it is clear that aquatic plants have potentially high biomass productivities and, specifically for the case of microalgae, could produce a high-quality, high-value biomass suitable for conversion to fuels and extraction of other products. A list of the relative advantages and disadvantages of aquatic plant energy systems in comparison with the concepts of terrestrial tree or herbaceous plant energy farming is given. Three favorable aspects of aquatic plant biomass systems should be stressed - the relative short-term research and development effort that will be required to determine the practical feasibility of such systems, the continuous production nature of such systems, and the relative independence of aquatic biomass systems from soil characteristics and weather fluctuations. The fast generation times of most aquatic plants allow rapid data acquisition, as compared to even short-rotation trees.

  8. Classroom measurements of sound speed in fresh/saline water.

    PubMed

    Carman, Jessie C

    2012-03-01

    A tabletop apparatus permitting demonstrations and hands-on student exercises in the measurement of sound speed in water as a function of both temperature and salinity, at atmospheric pressure, is described. By measuring sound speed using a differential technique with a precisely measured path length difference Δx, errors due to uncertainty in original path length are minimized. The apparatus can be used to measure sound speed in freshwater baths of varying temperature and room temperature baths of varying salinities to provide the student a clear picture of sound speed variation along two axes. © 2012 Acoustical Society of America

  9. Dangerous waters: outbreak of eye lesions caused by fresh water sponge spicules

    PubMed Central

    Cruz, A A V; Alencar, V M; Medina, N H; Volkmer-Ribeiro, C; Gattás, V L; Luna, E

    2013-01-01

    Purpose To describe an extremely uncommon outbreak of eye lesions in a specific area of the Brazilian Amazonia. Methods Prospective noncomparative case series. Fifty-nine patients who developed eye lesions after swimming in the Araguaia river of Tocantins state in Brazil were examined. A team of ophthalmologists equipped with a slit-lamp, gonioscopic lenses, and indirect ophthalmoscopy performed full eye examination. Analysis of the flora and fauna of the river water was undertaken by a group of experts. Results and Conclusions Eighty-three eyes were affected. The most common lesions were corneal opacities seen in 34 eyes and conjunctival nodules diagnosed in 12 eyes. Severe visual acuity loss was detected in seven children with unilateral anterior chamber lesions. Spicules of the sponge species Drulia uruguayensis and Drulia ctenosclera were found inside three blind eyes that have been enucleated for diagnostic purposes. All eye lesions could be attributed to an outbreak of foreign bodies from fresh water sponges. Organic enrichment of the water resulting from the absence of sanitation probably was the key factor, which initiated a cycle of ecological imbalance that provoked human disease. PMID:23306731

  10. Transfer of Acanthamoeba spp. to fresh produce from water and environmental surfaces.

    PubMed

    Hsueh, T-Y; Gibson, K E

    2015-08-01

    Human noroviruses (HuNoV) are the primary cause of food-borne disease outbreaks in the United States. The most frequent commodities implicated in HuNoV outbreaks are leafy greens where contamination may occur during production and harvesting practices. With respect to the transmission of HuNoV to fresh produce, one hypothesis is that free-living amoebae that are ubiquitous in the environment (soil, sediments and water) can serve as vehicles of contamination through interaction with viruses. Here, we investigated the transfer of Acanthamoeba spp. both alone and associated with murine norovirus (MNV-1)-a surrogate for HuNoV-from water and food contact surfaces to fresh produce to understand the transfer of amoebae and the effect of virus association with amoeba on transferability, if any. In water containing a low concentration of amoebae (3 log10  cell ml(-1) ), 3·85 log10 amoebae transferred to 5 g of leafy greens, and for 5 cherry tomatoes, 3·4 to 3·5 log10 amoebae were transferred. Similarly, for high concentrations of amoeba (5 log10  cell ml(-1) ) in water, 6·14 and 5·81 log10 amoebae were transferred to 5 g leafy greens and five cherry tomatoes respectively. However, the transfer of amoebae from food contact surfaces to fresh produce was very limited. In addition, amoebae association with MNV-1 did not impact transferability. The results of this study provide a better understanding of physical parameters (e.g. surface area and texture of fresh produce, transfer medium-water vs surface) potentially associated with transfer of free-living amoeba to fresh produce as well as the role that contaminated water (irrigation or wash water) may play in the transmission of enteric viruses associated with amoeba. © 2015 The Society for Applied Microbiology.

  11. Episodic fresh surface waters in the Eocene Arctic Ocean.

    PubMed

    Brinkhuis, Henk; Schouten, Stefan; Collinson, Margaret E; Sluijs, Appy; Sinninghe Damsté, Jaap S; Dickens, Gerald R; Huber, Matthew; Cronin, Thomas M; Onodera, Jonaotaro; Takahashi, Kozo; Bujak, Jonathan P; Stein, Ruediger; van der Burgh, Johan; Eldrett, James S; Harding, Ian C; Lotter, André F; Sangiorgi, Francesca; van Konijnenburg-van Cittert, Han; de Leeuw, Jan W; Matthiessen, Jens; Backman, Jan; Moran, Kathryn

    2006-06-01

    It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain oceanic conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic Ocean by the onset of the middle Eocene epoch (approximately 50 Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface waters during an approximately 800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic Ocean that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from approximately 10 degrees C to 13 degrees C, pointing to simultaneous increases in salt and heat supply owing to the influx of waters from adjacent oceans. We suggest that onset and termination of the Azolla phase depended on the degree of oceanic exchange between Arctic Ocean and adjacent seas.

  12. Episodic fresh surface waters in the Eocene Arctic Ocean

    USGS Publications Warehouse

    Brinkhuis, H.; Schouten, S.; Collinson, M.E.; Sluijs, A.; Damste, J.S.S.; Dickens, G.R.; Huber, M.; Cronin, T. M.; Onodera, J.; Takahashi, K.; Bujak, J.P.; Stein, R.; Van Der Burgh, J.; Eldrett, J.S.; Harding, I.C.; Lotter, A.F.; Sangiorgi, F.; Cittert, H.V.K.V.; De Leeuw, J. W.; Matthiessen, J.; Backman, J.; Moran, K.

    2006-01-01

    It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain oceanic conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic Ocean by the onset of the middle Eocene epoch (???50 Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface waters during an ???800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic Ocean that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from ???10??C to 13??C, pointing to simultaneous increases in salt and heat supply owing to the influx of waters from adjacent oceans. We suggest that onset and termination of the Azolla phase depended on the degree of oceanic exchange between Arctic Ocean and adjacent seas. ?? 2006 Nature Publishing Group.

  13. Fresh water supply to oil producing countries by means of crude oil tankers

    SciTech Connect

    Akiyama, Y.

    1980-12-01

    Oil producing area and oil consuming area in the world sometimes coincide with water deficient area and water surplus area, like as Arabian Gulf area and Japan. Ocean transportation of oil over these areas is being made by oil tankers, but return voyage of tankers has so far not been put to productive use. By boost of international regulation to prevent marine pollution caused by discharging sea water ballast, such half used bridge will provide with practical measures of fresh water transportation to oil producing arid area. This is to report the proposed scheme to transport and supply fresh water to Arabian Gulf area by means of return voyages of crude oil tankers voyaging between Arabian Gulf area and Japan with it technical and economical aspects as well as its effect and additional advantages to be expected by the scheme.

  14. Water pollution effects of metals on fresh water fish. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-06-01

    The bibliography contains citations concerning laboratory and field studies regarding effects of metals on fresh water fish. Topics include toxicity effects on fish species, bioaccumulation, fish physiology, acidification and detoxification, aquatic ecosystems, and water quality management. Environmental monitoring systems and pollution effects on food chains are examined. (Contains 50-250 citations and includes a subject term index and title list.)

  15. Fluctuations of fresh-saline water interface and of water table induced by sea tides in unconfined aquifers

    NASA Astrophysics Data System (ADS)

    Levanon, Elad; Shalev, Eyal; Yechieli, Yoseph; Gvirtzman, Haim

    2016-10-01

    This study examines effects of tides on fluctuations of the fresh-saline water interface and the groundwater level in unconfined coastal aquifers using a two-dimensional numerical model. The time-lags of the simulated hydraulic heads and salinities fluctuations compared to sea level fluctuations are analyzed using cross-correlation analysis. The results show that both the fresh-saline water interface and the groundwater level are affected harmonically by sea tide fluctuations. However, significantly different time-lags are obtained between the hydraulic head in the deeper and upper parts of the aquifer, and between head and salinity in the fresh-saline water interface. The hydraulic head in the deeper part of the aquifer responses much faster to sea level fluctuations than in the upper part. Surprisingly, a similar difference is detected between the time-lag of the hydraulic head in the fresh-saline water interface and the time-lag of the salinity at the same location. Furthermore, the time-lag of the salinity in the fresh-saline water interface is similar to the time-lag of the water table. We suggest a comprehensive mechanism for tidal influence on the coastal groundwater system, in which two main processes act simultaneously. First, sea tide causes a pressure head wave which propagates into the saturated zone of the aquifer, governed by the diffusivity of the aquifer (Ks/Ss). Second, this pressure head wave is attenuated at the water table due to the unsaturated flow within the capillary fringe which occurs during groundwater level oscillations. Because the tidal forcing acts on the sea-floor boundary and the attenuation of the groundwater level due to capillary effect acts on the groundwater table, two dimensional distributions of time-lag and hydraulic head amplitude are created. The capillary effect in the unsaturated zone plays a key role not only in the water table fluctuations as shown previously, but also on the salinity fluctuations in the fresh

  16. Risk of otitis externa after swimming in recreational fresh water lakes containing Pseudomonas aeruginosa.

    PubMed Central

    van Asperen, I. A.; de Rover, C. M.; Schijven, J. F.; Oetomo, S. B.; Schellekens, J. F.; van Leeuwen, N. J.; Collé, C.; Havelaar, A. H.; Kromhout, D.; Sprenger, M. W.

    1995-01-01

    OBJECTIVE--To determine whether an outbreak of otitis externa was due to bathing in recreational fresh water lakes and to establish whether the outbreak was caused by Pseudomonas aeruginosa in the water. DESIGN--Matched case-control study. SETTING--The Achterhoek area, the Netherlands. SUBJECTS--98 cases with otitis externa and 149 controls matched for age, sex, and place of residence. MAIN OUTCOME MEASURES--Odds ratios for type of swimming water and frequency of swimming; presence of P aeruginosa in ear swabs and fresh water lakes. RESULTS--Otitis externa was strongly associated with swimming in recreational fresh water lakes in the previous two weeks (odds ratio 15.5 (95% confidence interval) 4.9 to 49.2) compared with non-swimming). The risk increased with the number of days of swimming, and subjects with recurrent ear disease had a greatly increased risk. The lakes met the Dutch bathing water standards and those set by the European Commission for faecal pollution in the summer of 1994, but P aeruginosa was isolated from all of them, as well as from the ear swabs of 78 (83%) of the cases and 3 (4%) of the controls. CONCLUSIONS--Even when current bathing water standards are met, swimming can be associated with a substantial risk of otitis externa because of exposure to P aeruginosa. People with recurrent ear disease should take special care when swimming in waters containing P aeruginosa. PMID:8520277

  17. The widespread threat of calcium decline in fresh waters.

    PubMed

    Jeziorski, Adam; Yan, Norman D; Paterson, Andrew M; Desellas, Anna M; Turner, Michael A; Jeffries, Dean S; Keller, Bill; Weeber, Russ C; McNicol, Don K; Palmer, Michelle E; McIver, Kyle; Arseneau, Kristina; Ginn, Brian K; Cumming, Brian F; Smol, John P

    2008-11-28

    Calcium concentrations are now commonly declining in softwater boreal lakes. Although the mechanisms leading to these declines are generally well known, the consequences for the aquatic biota have not yet been reported. By examining crustacean zooplankton remains preserved in lake sediment cores, we document near extirpations of calcium-rich Daphnia species, which are keystone herbivores in pelagic food webs, concurrent with declining lake-water calcium. A large proportion (62%, 47 to 81% by region) of the Canadian Shield lakes we examined has a calcium concentration approaching or below the threshold at which laboratory Daphnia populations suffer reduced survival and fecundity. The ecological impacts of environmental calcium loss are likely to be both widespread and pronounced.

  18. Benthic plastic debris in marine and fresh water environments.

    PubMed

    Corcoran, Patricia L

    2015-08-01

    This review provides a discussion of the published literature concerning benthic plastic debris in ocean, sea, lake, estuary and river bottoms throughout the world. Although numerous investigations of shoreline, surface and near-surface plastic debris provide important information on plastic types, distribution, accumulation, and degradation, studies of submerged plastic debris have been sporadic in the past and have become more prominent only recently. The distribution of benthic debris is controlled mainly by combinations of urban proximity and its association with fishing-related activities, geomorphology, hydrological conditions, and river input. High density plastics, biofouled products, polymers with mineral fillers or adsorbed minerals, and plastic-metal composites all have the potential to sink. Once deposited on the bottoms of water basins and channels, plastics are shielded from UV light, thus slowing the degradation process significantly. Investigations of the interactions between benthic plastic debris and bottom-dwelling organisms will help shed light on the potential dangers of submerged plastic litter.

  19. Fate of toxic metals during estuarine mixing of fresh water with saline water.

    PubMed

    Farajnejad, Hamed; Karbassi, Abdolreza; Heidari, Mehdi

    2017-10-04

    Metals are among the most common environmental pollutants, and their presence in high concentration in waters and biota have devastating effects on flora, fauna, and human health. Flocculation process of metals during estuarine mixing can reduce the environmental hazards of metals and also can provide micronutrients to the aquatic system. The present investigation provides a thorough study of eliminating colloidal elements of copper, manganese, nickel, lead, and zinc during estuarine mixing of Shalmanrood River water with Caspian Sea water in Iran. The processes of flocculation were carried out in six different salinity regimes (0.45-2.4 ppt). The obtained result is indicative of non-conservative behavior of the studied metals. Higher flocculation resulted in a lower salinity regime. The obtained results indicated that most of the metals were eliminated during the initial mixing of fresh water with sea water at 0.45-0.9 ppt salinity interval. The trend of flocculation rates of elements is as follows: Zn (59.3%) > Pb (47.6%) > Mn (37.5%) > Cu (29.2%) > Ni (27%).The annual average load of copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) from Shalmanrood River to Caspian Sea decreases as a result of flocculation process from 9.9, 7.7, 8.9, 5.1, and 23.2 tons per year to 7, 4.8, 6.5, 2.7, and 9.4 tons per year, respectively. According to the cluster analysis, parameters such as temperature, pH, and Eh do not have any impact on flocculation of elements expect for Pb. The only parameter that influences the flocculation of Mn is the salinity. Metal speciation studies that are carried out by Eh-pH software show that the studied metals are present as oxides (Zn, Cu, and Ni) and hydroxides (Mn and Pb).

  20. Fresh and saline ground-water zones in the Punjab region, West Pakistan

    USGS Publications Warehouse

    Swarzenski, W.V.

    1968-01-01

    An extensive program of test drilling and water sampling, undertaken by the Water and Soils Investigation Division (WASID) of the West Pakistan Water and Power Development Authority (WAPDA) to evaluate hydrologic problems related to waterlogging and soil salinity, has furnished data for the delineation of fresh and saline ground-water zones in the Punjab region of West Pakistan. Fresh ground water containing generally less than 500 ppm (parts per million) of total dissolved solids is found in wide belts paralleling the major rivers and in other areas of ground-water recharge. The fresh groundwater zone of upper (northeastern) Rechna Doab, where annual precipitation in places exceeds 30 inches, is the most extensive of the Punjab region and attains a depth of 1,700 feet or more below land surface near Gujranwala. Fresh ground water adjacent to the Indus River extends locally to depths of about l,500 feet. Saline ground water occurs downgradient from sources of recharge, particularly in the central parts of the interfluvial areas. Also, available data indicate a gradual increase in mineralization with depth and distance from sources of fresh-water recharge. Thus, even extensive fresh-water zones appear to be underlain, at variable depths, by saline ground water in most of the Punjab region. The saline ground waters of the Punjab region do not constitute, however, a distinct salt-water body that can be defined in terms of stratigraphic position, sea-level datum, particular lithology, or by chemical character. The ground waters of the Punjab region are characterized by a gradation from calcium magnesium bicarbonate types, near the sources of recharge, to waters containing a dominant proportion of sodium. Water containing from 500 to 1,000 ppm is commonly of the sodium bicarbonate type, or it may be of the mixed type, having about equal proportions of the common anions (bicarbonate, chloride, and sulfate). With increasing mineralization from about 1,000 to 3,000 ppm

  1. Evaluation of the impact of hot water treatment on the sensory quality of fresh tomatoes

    USDA-ARS?s Scientific Manuscript database

    Minimizing the effects of chilling injury during shelf-life is important for maintaining the sensory quality of fresh tomato fruit. Postharvest hot water treatments within certain limits of exposure time and temperature have been shown to increase resistance of tomatoes to chilling injury. Mature-gr...

  2. [Underwater dive in fresh water complicated by a cardiorespiratory arrest on obstructive shock].

    PubMed

    Bourmanne, E; Jacobs, D; Caldow, M; El Kaissi, M

    2015-01-01

    We present the case of a french patient who dived in fresh water in Lac de l'Eau d'Heure on 8 December 2014. The 35 meters deep diving was complicated by an obstructive shock resulting from lung overpressure and decompression illness.

  3. Bridging the Rubicon: phylogenetic analysis reveals repeated colonizations of marine and fresh waters by thalassiosiroid diatoms.

    PubMed

    Alverson, Andrew J; Jansen, Robert K; Theriot, Edward C

    2007-10-01

    Salinity imposes a significant barrier to the distribution of many organisms, including diatoms. Diatoms are ancestrally marine, and the number of times they have independently colonized fresh waters and the physiological adaptations that facilitated these transitions remain outstanding questions in diatom evolution. The colonization of fresh waters by diatoms has been compared to "crossing the Rubicon," implying that successful colonization events are rare, irreversible, and lead to substantial species diversification. To test these hypotheses, we reconstructed the phylogeny of Thalassiosirales, a diatom lineage with high diversity in both marine and fresh waters. We collected approximately 5.3kb of DNA sequence data from the nuclear (SSU and partial LSU rDNA) and chloroplast genomes (psbC and rbcL) and reconstructed the phylogeny using parsimony and Bayesian methods. Alternative topology tests strongly reject all previous colonization hypotheses, including monophyly of the predominantly freshwater Stephanodiscaceae. Results showed at least three independent colonizations of fresh waters, and whereas previous accounts of freshwater-to-marine transitions have been discounted, these results provide compelling evidence for as many as three independent re-colonizations of the marine habitat, two of which led to speciation events. This study adds valuable phylogenetic context to previous debate about the nature of the salinity barrier in diatoms and provides compelling evidence that, at least for Thalassiosirales, the salinity barrier might be less formidable than previously thought.

  4. Estimating dry matter content of fresh leaves from residuals between leaf and water reflectance

    USDA-ARS?s Scientific Manuscript database

    At 1722 nm wavelength, there is an absorption feature of leaf dry matter based on a C—H stretch overtone, which is difficult to detect in fresh green leaves due to the absorption spectrum of liquid water. We applied a method originally proposed by B. -C. Gao and A. F. H. Goetz (1994, Remote Sensing ...

  5. Decapod crustaceans in fresh waters of southeastern Bahia, Brazil.

    PubMed

    de Almeida, Alexandre Oliveira; Coelho, Petrônio Alves; Luz, Joaldo Rocha; dos Santos, José Tiago Almeida; Ferraz, Neyva Ribeiro

    2008-09-01

    A total of 117 species of freshwater decapod crustaceans are known from Brazil. Knowledge regarding the fauna of Decapoda from inland waters in the state of Bahia, northeast Brazil, is incipient. In spite of its wide territory and rich hydrographic net, only 13 species of limnetic decapods have been reported from that state. The objective of this contribution was to survey decapod crustaceans of some hydrographic basins in southeastern Bahia. The material described herein was obtained in samplings conducted between 1997 and 2005. Voucher specimens were deposited in the carcinological collections of the Museu de Zoologia, Universidade Estadual de Santa Cruz, Ilhéus, Brazil, and Departamento de Oceanografia, Universidade Federal de Pernambuco, Recife, Brazil. A total of 13 species was collected. The carideans were represented by the atyids Atya scabra (Leach, 1815) and Potimirim potimirim (Müller, 1881) and the palaemonids Macrobrachium acanthurus (Wiegmann, 1836), M. amazonicum (Heller, 1862), M. carcinus (Linnaeus, 1758), M. heterochirus (Wiegmann, 1836), M. jelskii (Miers, 1877), M. olfersi (Wiegmann, 1836), and Palaemon (Palaemon) pandaliformis (Stimpson, 1871). The brachyurans were represented by the portunids Callinectes bocourti A. Milne-Edwards, 1879 and C. sapidus Rathbun, 1895, the trichodactylid Trichodactylus fluviatilis Latreille, 1828 and the panopeid Panopeus rugosus A. Milne-Edwards, 1881. Macrobrachium heterochirus represents a new record from Bahia, and M. amazonicum is reported for the first time in southeast Bahia. The occurrence of two extreme different forms of T. fluviatilis was observed. Form A is characterized by the frontal margin of carapace bordered by conspicuous granules, the anterolateral margin provided with developed teeth plus granules, and the posterolateral margin provided with granulation similar to that found on the front. In form B the frontal margin is smooth or has an inconspicuous granulation; the anterolateral margin is

  6. Release of reduced inorganic selenium species into waters by the green fresh water algae Chlorella vulgaris.

    PubMed

    Simmons, Denina Bobbie Dawn; Wallschläger, Dirk

    2011-03-15

    The common green fresh water algae Chlorella vulgaris was exposed to starting concentrations of 10 μg/L selenium in the form of selenate, selenite, or selenocyanate (SeCN(-)) for nine days in 10% Bold's basal medium. Uptake of selenate was more pronounced than that of selenite, and there was very little uptake of selenocyanate. Upon uptake of selenate, significant quantities of selenite and selenocyanate were produced by the algae and released back into the growth medium; no selenocyanate was released after selenite uptake. Release of the reduced metabolites after selenate exposure appeared to coincide with increasing esterase activity in solution, indicating that cell death (lysis) was the primary emission pathway. This is the first observation of biotic formation of selenocyanate and its release into waters from a nonindustrial source. The potential environmental implications of this laboratory observation are discussed with respect to the fate of selenium in impacted aquatic systems, the ecotoxicology of selenium bioaccumulation, and the interpretation of environmental selenium speciation data generated, using methods incapable of positively identifying reduced inorganic selenium species, such as selenocyanate.

  7. Production of algal-based biofuel using non-fresh water sources.

    SciTech Connect

    Sun, Amy Cha-Tien; Reno, Marissa Devan

    2007-09-01

    The goal of this LDRD involves development of a system dynamics model to understand the interdependencies between water resource availability and water needs for production of biofuels. Specifically, this model focuses on availability and feasibility of non-traditional water sources from dairy wastewater, produced water from crude oil production and from coal-bed methane gas extraction for the production of algal-based biofuel. The conceptual simulation framework and historical data are based on two locales within New Mexico, the San Juan basin in the northwest and the Permian basin in the southeast, where oil and gas drilling have increased considerably in the last ten years. The overall water balance ignores both transportation options and water chemistry and is broken down by county level. The resulting model contains an algal growth module, a dairy module, an oil production module, and a gas production module. A user interface is also created for controlling the adjustable parameters in the model. Our preliminary investigation indicates a cyclical demand for non-fresh water due to the cyclical nature of algal biomass production and crop evapotranspiration. The wastewater from the dairy industry is not a feasible non-fresh water source because the agricultural water demand for cow's dry feed far exceeds the amount generated at the dairy. The uncertainty associated with the water demand for cow's dry matter intake is the greatest in this model. The oil- and gas-produced water, ignoring the quality, provides ample supply for water demand in algal biomass production. There remains work to address technical challenges associated with coupling the appropriate non-fresh water source to the local demand.

  8. Developing reservoir monthly inflow forecasts using artificial intelligence and climate phenomenon information

    NASA Astrophysics Data System (ADS)

    Yang, Tiantian; Asanjan, Ata Akbari; Welles, Edwin; Gao, Xiaogang; Sorooshian, Soroosh; Liu, Xiaomang

    2017-04-01

    Reservoirs are fundamental human-built infrastructures that collect, store, and deliver fresh surface water in a timely manner for many purposes. Efficient reservoir operation requires policy makers and operators to understand how reservoir inflows are changing under different hydrological and climatic conditions to enable forecast-informed operations. Over the last decade, the uses of Artificial Intelligence and Data Mining [AI & DM] techniques in assisting reservoir streamflow subseasonal to seasonal forecasts have been increasing. In this study, Random Forest [RF), Artificial Neural Network (ANN), and Support Vector Regression (SVR) are employed and compared with respect to their capabilities for predicting 1 month-ahead reservoir inflows for two headwater reservoirs in USA and China. Both current and lagged hydrological information and 17 known climate phenomenon indices, i.e., PDO and ENSO, etc., are selected as predictors for simulating reservoir inflows. Results show (1) three methods are capable of providing monthly reservoir inflows with satisfactory statistics; (2) the results obtained by Random Forest have the best statistical performances compared with the other two methods; (3) another advantage of Random Forest algorithm is its capability of interpreting raw model inputs; (4) climate phenomenon indices are useful in assisting monthly or seasonal forecasts of reservoir inflow; and (5) different climate conditions are autocorrelated with up to several months, and the climatic information and their lags are cross correlated with local hydrological conditions in our case studies.

  9. Pesticides, fresh water fish, liver flukes and nitrosamines: A story of cholangiocarcinoma development in Thailand.

    PubMed

    Wiwanitkit, Viroj

    2009-01-01

    Cholangiocarcinoma is a common hepatobiliary carcinoma in Thailand. It is believed that both chronic exposure to liver fluke infestation and nitrosamine exposure are the two main underlying factors leading to the carcinogenesis. Here, the author further extrapolates and proposes a new hypothesis based on the environmental ecological data that the stimulation of fresh water fish by contaminated pesticide in water reservoirs might be a possible background of the high prevalence of cholangiocarcinoma in Thailand.

  10. Renal effects of fresh water-induced hypo-osmolality in a marine adapted seal

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Wade, C. E.; Costa, D. P.; Ortiz, C. L.

    2002-01-01

    With few exceptions, marine mammals are not exposed to fresh water; however quantifying the endocrine and renal responses of a marine-adapted mammal to the infusion of fresh water could provide insight on the evolutionary adaptation of kidney function and on the renal capabilities of these mammals. Therefore, renal function and hormonal changes associated with fresh water-induced diuresis were examined in four, fasting northern elephant seal ( Mirounga angustirostris) (NES) pups. A series of plasma samples and 24-h urine voids were collected prior to (control) and after the infusion of water. Water infusion resulted in an osmotic diuresis associated with an increase in glomerular filtration rate (GFR), but not an increase in free water clearance. The increase in excreted urea accounted for 96% of the increase in osmotic excretion. Following infusion of fresh water, plasma osmolality and renin activity decreased, while plasma aldosterone increased. Although primary regulators of aldosterone release (Na(+), K(+) and angiotensin II) were not significantly altered in the appropriate directions to individually stimulate aldosterone secretion, increased aldosterone may have resulted from multiple, non-significant changes acting in concert. Aldosterone release may also be hypersensitive to slight reductions in plasma Na(+), which may be an adaptive mechanism in a species not known to drink seawater. Excreted aldosterone and urea were correlated suggesting aldosterone may regulate urea excretion during hypo-osmotic conditions in NES pups. Urea excretion appears to be a significant mechanism by which NES pups sustain electrolyte resorption during conditions that can negatively affect ionic homeostasis such as prolonged fasting.

  11. Heterogeneous photocatalytic disinfection of wash waters from the fresh-cut vegetable industry.

    PubMed

    Selma, María Victoria; Allende, Ana; López-Gálvez, Francisco; Conesa, María Angeles; Gil, María Isabel

    2008-02-01

    The effectiveness of photocatalytic disinfection for control of natural and potentially pathogenic microflora in wash waters used for fresh-cut vegetables was evaluated. Wash waters for lettuce, escarole, chicory, carrot, onion, and spinach from a fresh-cut vegetable processing plant were treated with a titanium dioxide (TiO2) photocatalytic system. The vegetable wash waters were impelled out with a pump at a flow rate of 1,000 liters/h and conducted through a stainless steel circuit to the filtration system to reach the TiO2 photocatalyst fiber, which was illuminated with a 40-W UV-C lamp. The microbial and physicochemical qualities of the wash water were analyzed. Heterogeneous photocatalysis was an effective disinfection method, reducing counts of bacteria, molds, and yeasts. Most of the treated wash waters had total bacteria reductions of 4.1 +/- 1.3 to 4.8 +/- 0.4 log CFU/ml after 10 min of treatment when compared with untreated water. Higher decontamination efficacy was observed in carrot wash water (6.2 +/- 0.1-log reductions), where turbidity and organic matter were lower than those in the wash waters for other vegetables. The tested heterogeneous photocatalytic system also was effective for reducing water turbidity, although chemical oxygen demand was unaffected after the treatments. The efficacy of the photocatalytic system for reducing microbial load depended on the physicochemical characteristics of the wash water, which depended on the vegetable being washed. The conclusions derived from this study illustrate that implementation of a heterogeneous photocatalytic system in the fresh-cut vegetable washing processes could allow the reuse of wash water.

  12. Water quality of the Boca Raton canal system and effects of the Hillsboro Canal inflow, southeastern Florida, 1990-91

    USGS Publications Warehouse

    McKenzie, D.J.

    1995-01-01

    The City of Boca Raton in southeastern Palm Beach County, Florida, is an urban residential area that has sustained a constant population growth with subsequent increase in water use. The Boca Raton network of canals is controlled to provide for drainage of excess water, to maintain proper coastal ground-water levels to prevent saltwater intrusion, and to recharge the surficial aquifer system from which the city withdraws potable water. Most of the water supplied to the Boca Raton canal system and the surficial aquifer system, other than rainfall and runoff, is pumped from the Hillsboro Canal. The Biscayne aquifer, principal hydrogeologic unit of the surficial aquifer system, is highly permeable and there is a close relation between water levels in the canals and the aquifer. The amount of water supplied by seepage from the conservation areas is unknown. Because the Hillsboro Canal flows from Lake Okeechobee and Water Conservation Areas 1 and 2, which are places of more highly mineralized ground water and surface water, the canal is a possible source of contamination. Water samples were collected at 10 canal sites during wet and dry seasons and analyzed for major inorganic ions and related characteristics, nutrients, and trace elements. All concentrations were generally within or less than the drinking-water standards established by the Florida Department of Environmental Protection. The high concentrations of sodium and chloride that were detected in samples from the Boca Raton canal system are probably from the more mineralized water of the Hillsboro Canal. Other water-quality data, gathered from various sources from 1982 through 1991, did not indicate any significant changes nor trends. The effects of the Hillsboro Canal on the water quality of the Boca Raton canal system are indicated by increased concentrations of sodium, chloride, dissolved solids, and total organic carbon. Concentrations of the constituents in the canal water generally decrease with distance

  13. Closed-form approximations for two-dimensional groundwater age patterns in a fresh water lens.

    PubMed

    Greskowiak, Janek; Röper, Tania; Post, Vincent E A

    2013-01-01

    Simple closed-form approximations are presented for calculating the steady-state groundwater age distribution in two-dimensional vertical cross sections of idealized fresh water lenses overlying salt water, for aquifers that are vertically semi-infinite and of finite thickness. The approximations are developed on the basis of existing one-dimensional analytical solutions for travel-time calculation in fresh water lenses and approximate streamline formulations. The two-dimensional age distributions based on the closed-form solutions match convincingly with numerical simulations. As expected, notable deviations from the numerical solution are encountered at the groundwater flow divide and when submarine groundwater discharge occurs. Ratios of recharge over hydraulic conductivities are varied to explore how the magnitude of the deviations changes, and it is found that the approximate closed-form solutions perform well over a range of conditions found in natural systems.

  14. Effects of temperature on electrolyte balance and osmoregulation of the alewife (Alosa pseudoharengus) in fresh and sea water

    USGS Publications Warehouse

    Stanley, Jon G.; Colby, Peter J.

    1971-01-01

    In the laboratory, alewife mortalities caused by increasing or decreasing temperatures were about equal in fresh water and sea water. These findings suggest that salinity does not modify the capacity of alewives to tolerate acute temperature stress.

  15. Behavioural salinity preferences of juvenile green sturgeon Acipenser medirostris acclimated to fresh water and full-strength salt water.

    PubMed

    Poletto, J B; Cocherell, D E; Klimley, A P; Cech, J J; Fangue, N A

    2013-02-01

    To quantify the salinity preference of juvenile green sturgeon Acipenser medirostris, two groups of A. medirostris [140 days post hatch (dph); total length (L(T) ) 38.0-52.5 cm] were acclimated to either near fresh water (mean ± s.e. salinity = 3.2 ± 0.6) or full-strength salt water (34.1 ± 1.2) over 8 weeks. Following acclimation, the two groups were divided into experimental and control groups, where experimental A. medirostris from both freshwater and saltwater acclimations were individually introduced (200-220 dph) into a rectangular salinity-preference flume (maximum salinity gradient: 5-33). Control A. medirostris were presented with only their acclimation water (fresh water or salt water) on both sides of the flume. It was demonstrated that A. medirostris acclimated to both salt water and fresh water spent a significantly greater amount of time on the side of the testing area with the highest salinity concentration (P < 0.05 and P < 0.001, respectively) while control A. medirostris spent an equal amount of time on each side of the flume. These findings indicate that juvenile A. medirostris are not only capable of detecting salt water within the first year of their lives but perhaps are actively seeking out saline environments as they move through a watershed. Establishing A. medirostris salinity preferences provides a better understanding of the early life history of this threatened species, shedding light on possible outmigration timing.

  16. Effects of small-scale vertical variations in well-screen inflow rates and concentrations of organic compounds on the collection of representative ground-water-quality samples

    USGS Publications Warehouse

    Gibs, Jacob; Brown, G. Allan; Turner, Kenneth S.; MacLeod, Cecilia L.; Jelinski, James; Koehnlein, Susan A.

    1993-01-01

    Because a water sample collected from a well is an integration of water from different depths along the well screen, measured concentrations can be biased if analyte concentrations are not uniform along the length of the well screen. The resulting concentration in the sample, therefore, is a function of variations in well-screen inflow rate and analyte concentration with depth. A multiport sampler with seven short screened intervals was designed and used to investigate small-scale vertical variations in water chemistry and aquifer hydraulic conductivity in ground water contaminated by leaded gasoline at Galloway Township, Atlantic County, New Jersey. The multiport samplers were used to collect independent samples from seven intervals within the screened zone that were flow-rate weighted and integrated to simulate a 5-foot-long, 2.375-inch- outside-diameter conventional wire-wound screen. The integration of the results of analyses of samples collected from two multiport samplers showed that a conventional 5-foot-long well screen would integrate contaminant concentrations over its length and resulted in an apparent contaminant concentration that was a little as 28 percent of the maximum concentration observed in the multiport sampler.

  17. Of all the planet's renewable resources, fresh water may be the most unforgiving.

    PubMed

    1994-01-01

    Access to water is essential to social and economic development and the stability of cultures and civilizations throughout the world historically. The UN Commission on Sustainable Development in mid-1993 emphasized the importance of transfer of technology to poor countries for improvement in water quality. Less attention has been given to the issue of water availability. The amount of fresh water is finite. The capacity for storage of water has increased over time, but commodity expansion has not improved. Salinization processes have proven to be too costly in dollars, pollution, and nonrenewable fossil fuels. As population grows, the average amount of fresh water available declines. Improvements can only be made in efficiency of usage or conservation. Per capita use of water doubled to 800 cubic meters per person per year. But global use of water increased by 4 times in 50 years. Only 2.5% of the world's 1.4 billion cubic kilometers of water is fit for drinking, crops, or most industrial uses. In Africa and the Middle East water resources are declining in availability and quality. An important feature of water resources is the extent of replenishment in the hydrologic cycle. Water availability from rain and snow amounts to about 113,000 cubic kilometers yearly, of which 72,000 evaporates. Aquifers, rivers, and oceans are renewed with the remaining 41,000 cu km. About 50% returns to oceans and 1/8 is too far from human habitation for use. Estimates of renewable freshwater average 9-14,000 cu km yearly, and a substantial amount is needed to sustain ecosystems in rivers, wetlands, and coastal waters. Internal resources within each country may amount to only about 20% of potential water resources, due to water storage suitability of the land and the extent and condition of infrastructure.

  18. Salinization of a fresh palaeo-ground water resource by enhanced recharge.

    PubMed

    Leaney, F W; Herczeg, A L; Walker, G R

    2003-01-01

    Deterioration of fresh ground water resources caused by salinization is a growing issue in many arid and semi-arid parts of the world. We discuss here the incipient salinization of a 10(4) km2 area of fresh ground water (<3,000 mg/L) in the semiarid Murray Basin of Australia caused by widespread changes in land use. Ground water 14C concentrations and unsaturated zone Cl soil water inventories indicate that the low salinity ground water originated mainly from palaeo-recharge during wet climatic periods more than 20,000 years ago. However, much of the soil water in the 20 to 60 m thick unsaturated zone throughout the area is generally saline (>15,000 mg/L) because of relatively high evapotranspiration during the predominantly semiarid climate of the last 20,000 years. Widespread clearing of native vegetation over the last 100 years and replacement with crops and pastures leads to enhancement of recharge rates that progressively displace the saline soil-water from the unsaturated zone into the ground water. To quantify the impact of this new hydrologic regime, a one-dimensional model that simulates projected ground water salinities as a function of depth to ground water, recharge rates, and soil water salt inventory was developed. Results from the model suggest that, in some areas, the ground water salinity within the top 10 m of the water table is likely to increase by a factor of 2 to 6 during the next 100 years. Ground water quality will therefore potentially degrade beyond the point of usefulness well before extraction of the ground water exhausts the resource.

  19. Soil Moisture and Excavation Behaviour in the Chaco Leaf-Cutting Ant (Atta vollenweideri): Digging Performance and Prevention of Water Inflow into the Nest

    PubMed Central

    Pielström, Steffen; Roces, Flavio

    2014-01-01

    The Chaco leaf-cutting ant Atta vollenweideri is native to the clay-heavy soils of the Gran Chaco region in South America. Because of seasonal floods, colonies are regularly exposed to varying moisture across the soil profile, a factor that not only strongly influences workers' digging performance during nest building, but also determines the suitability of the soil for the rearing of the colony's symbiotic fungus. In this study, we investigated the effects of varying soil moisture on behaviours associated with underground nest building in A. vollenweideri. This was done in a series of laboratory experiments using standardised, plastic clay-water mixtures with gravimetric water contents ranging from relatively brittle material to mixtures close to the liquid limit. Our experiments showed that preference and group-level digging rate increased with increasing water content, but then dropped considerably for extremely moist materials. The production of vibrational recruitment signals during digging showed, on the contrary, a slightly negative linear correlation with soil moisture. Workers formed and carried clay pellets at higher rates in moist clay, even at the highest water content tested. Hence, their weak preference and low group-level excavation rate observed for that mixture cannot be explained by any inability to work with the material. More likely, extremely high moistures may indicate locations unsuitable for nest building. To test this hypothesis, we simulated a situation in which workers excavated an upward tunnel below accumulated surface water. The ants stopped digging about 12 mm below the interface soil/water, a behaviour representing a possible adaptation to the threat of water inflow field colonies are exposed to while digging under seasonally flooded soils. Possible roles of soil water in the temporal and spatial pattern of nest growth are discussed. PMID:24748382

  20. Vegetation dynamics in response to water inflow rates and fire in a brackish Typha domingensis Pers. marsh in the delta of the Colorado River, Mexico

    USGS Publications Warehouse

    Mexicano, Lourdes; Nagler, Pamela L.; Zamora-Arroyo, Francisco; Glenn, Edward P.

    2012-01-01

    The Cienega de Santa Clara is a 5600 ha, anthropogenic wetland in the delta of the Colorado River in Mexico. It is the inadvertent creation of the disposal of brackish agricultural waste water from the U.S. into the intertidal zone of the river delta in Mexico, but has become an internationally important wetland for resident and migratory water birds. We used high resolution Quickbird and WorldView-2 images to produce seasonal vegetation maps of the Cienega before, during and after a test run of the Yuma Desalting Plant, which will remove water from the inflow stream and replace it with brine. We also used moderate resolution, 16-day composite NDVI imagery from the Moderate Resolution Imaging Spectrometer (MODIS) sensors on the Terra satellite to determine the main factors controlling green vegetation density over the years 2000–2011. The marsh is dominated by Typha domingensis Pers. with Phragmites australis (Cav.) Trin. Ex Steud. as a sub-dominant species in shallower marsh areas. The most important factor controlling vegetation density was fire. Spring fires in 2006 and 2011 were followed by much more rapid green-up of T. domingensis in late spring and 30% higher peak summer NDVI values compared to non-fire years (P < 0.001). Fires removed thatch and returned nutrients to the water, resulting in more vigorous vegetation growth compared to non-fire years. The second significant (P < 0.01) factor controlling NDVI was flow rate of agricultural drain water from the U.S. into the marsh. Reduced summer flows in 2001 due to canal repairs, and in 2010 during the YDP test run, produced the two lowest NDVI values of the time series from 2000 to 2011 (P < 0.05). Salinity is a further determinant of vegetation dynamics as determined by greenhouse experiments, but was nearly constant over the period 2000–2011, so it was not a significant variable in regression analyses. It is concluded that any reduction in inflow volumes will result in a linear decrease in green foliage

  1. Artificial Injection of Fresh Water into a Confined Saline Aquifer: A Case Study at the Nakdong River Delta Area, Korea

    NASA Astrophysics Data System (ADS)

    Chung, S. Y.; Senapathi, V.; Rajendran, R.; Khakimov, E.

    2015-12-01

    Injection test in a confined saline aquifer was performed to assess the potential of artificial recharge as a means of replacing saline water with fresh water, thereby securing fresh groundwater resources for the Nakdong Delta area of Busan City, Korea. The study area comprises a confined aquifer, in which a 10~21m thick clay layer overlies 31.5~36.5 m thick of sand and a 2.8~11m thick layer of gravel. EC logging of five monitoring wells yielded a value of 7~44 mS/cm, with the transition between saline and fresh water occurring at a depth of 15-38 m. Above 5 m depth, water temperature was 10~15.5°C, whereas between 5 and 50 m depth, the temperature was 15.5~17℃ and pH was 7.15~7.49. The quality of injected fresh water was 388 μS/cm with the temperature of 6.2℃, and pH was 7.70. Approximately 950 m3 of fresh water was injected into the OW-5 injection well at a rate of 370 m3/day for 62 hours, after which the fresh water zone was detected by a CTD Diver installed at a depth of 40 m. The persistence of the fresh water zone was determined via EC and temperature logging at 1 day, 21 days, 62days and 95 days after injection. The contact between fresh and saline water in the injection well was represented by a sharp boundary rather than a transitional boundary. It was concluded that the injected fresh water occupied a specific space and served to maintain the original water quality throughout the observation period. Moreover, we suggest that artificial recharge via long-term injection could help secure a new alternative water resource in this saline coastal aquifer.

  2. Modelling the growth of Listeria monocytogenes in fresh green coconut (Cocos nucifera L.) water.

    PubMed

    Walter, Eduardo H M; Kabuki, Dirce Y; Esper, Luciana M R; Sant'Ana, Anderson S; Kuaye, Arnaldo Y

    2009-09-01

    The behaviour of Listeria monocytogenes in the fresh coconut water stored at 4 degrees C, 10 degrees C and 35 degrees C was studied. The coconut water was aseptically extracted from green coconuts (Cocos nucifera L.) and samples were inoculated in triplicate with a mixture of 5 strains of L. monocytogenes with a mean population of approximately 3 log(10) CFU/mL. The kinetic parameters of the bacteria were estimated from the Baranyi model, and compared with predictions of the Pathogen Modelling Program so as to predict its behaviour in the beverage. The results demonstrated that fresh green coconut water was a beverage propitious for the survival and growth of L. monocytogenes and that refrigeration at 10 degrees C or 4 degrees C retarded, but did not inhibit, growth of this bacterium. Temperature abuse at 35 degrees C considerably reduced the lagtimes. The study shows that L. monocytogenes growth in fresh green coconut water is controlled for several days by storage at low temperature, mainly at 4 degrees C. Thus, for risk population this product should only be drunk directly from the coconut or despite the sensorial alterations should be consumed pasteurized.

  3. Variations of natremia in sea kraits (Laticauda spp.) kept in seawater and fresh water.

    PubMed

    Brischoux, François; Briand, Marine J; Billy, Gopal; Bonnet, Xavier

    2013-10-01

    Marine tetrapods evolved specific excretory structures (e.g. salt glands) that maintain salt concentrations within a narrow range of variation. However, recent investigations showed that in some lineages (sea snakes), individuals dehydrate in seawater and cannot equilibrate their hydromineral balance without access to fresh water. How these marine species cope with salt gain is therefore puzzling. We sampled two species of amphibious sea kraits (Laticauda saintgironsi and L. laticaudata) in the field. We also experimentally investigated patterns of salt regulation, specifically variations in natremia (plasma sodium) and body mass (net water flow), in individuals transferred first to fresh water and then to seawater. Our results show that free-ranging sea kraits display hypernatremia (up to 205mmol·l(-1)). Experimental data showed that natremia markedly decreased in snakes exposed to fresh water and increased when they were transferred to saltwater, thereby demonstrating a marked flexibility in their relation to environmental conditions. A literature survey indicated that all free-ranging marine snake species usually display hypernatremia despite having functional salt glands. Overall, sea snakes exhibit a marked tolerance to salt load compared to other marine tetrapods and apparently trigger substantial salt excretion only once natremia exceeds a high threshold. We hypothesise that this high tolerance significantly decreases energetic costs linked to salt gland functioning.

  4. Relative Recovery of Thermal Energy and Fresh Water in Aquifer Storage and Recovery Systems.

    PubMed

    Miotliński, K; Dillon, P J

    2015-01-01

    This paper explores the relationship between thermal energy and fresh water recoveries from an aquifer storage recovery (ASR) well in a brackish confined aquifer. It reveals the spatial and temporal distributions of temperature and conservative solutes between injected and recovered water. The evaluation is based on a review of processes affecting heat and solute transport in a homogeneous aquifer. In this simplified analysis, it is assumed that the aquifer is sufficiently anisotropic to inhibit density-affected flow, flow is axisymmetric, and the analysis is limited to a single ASR cycle. Results show that the radial extent of fresh water at the end of injection is greater than that of the temperature change due to the heating or cooling of the geological matrix as well as the interstitial water. While solutes progress only marginally into low permeability aquitards by diffusion, conduction of heat into aquitards above and below is more substantial. Consequently, the heat recovery is less than the solute recovery when the volume of the recovered water is lower than the injection volume. When the full volume of injected water is recovered the temperature mixing ratio divided by the solute mixing ratio for recovered water ranges from 0.95 to 0.6 for ratios of maximum plume radius to aquifer thickness of 0.6 to 4.6. This work is intended to assist conceptual design for dual use of ASR for conjunctive storage of water and thermal energy to maximize the potential benefits.

  5. Effects of land use on fresh waters: Agriculture, forestry, mineral exploitation, urbanisation

    SciTech Connect

    Solbe, J.F.

    1986-01-01

    This book offers a broad consideration of the effects of land use on fresh waters above and below ground. Experts address a wide range of issues in relation to the four major uses of land. Taken from an international conference held at the University of Stirling in 1985, coverage includes sewerage and waste-water treatment, long-term contamination of aquifers below cities, mineral exploitation, use of water in food production, wood production and more. Remedies and areas requiring further study are outlined.

  6. Fresh-cut product sanitation and wash water disinfection: problems and solutions.

    PubMed

    Gil, Maria I; Selma, Maria V; López-Gálvez, Francisco; Allende, Ana

    2009-08-31

    It is well known that fresh-cut processors usually rely on wash water sanitizers to reduce microbial counts in order to maintain quality and extend shelf-life of the end product. Water is a useful tool for reducing potential contamination but it can also transfer pathogenic microorganisms. Washing with sanitizers is important in fresh-cut produce hygiene, particularly removing soil and debris, but especially in water disinfection to avoid cross-contamination between clean and contaminated product. Most of the sanitizing solutions induce higher microbial reduction after washing when compared to water washing, but after storage, epiphytic microorganisms grow rapidly, reaching similar levels. In fact, despite the general idea that sanitizers are used to reduce the microbial population on the produce, their main effect is maintaining the microbial quality of the water. The use of potable water instead of water containing chemical disinfection agents for washing fresh-cut vegetables is being advocated in some European countries. However, the problems of using an inadequate sanitizer or even none are considered in this manuscript. The need for a standardized approach to evaluate and compare the efficiency of sanitizing agents is also presented. Most new alternative techniques accentuate the problems with chlorine suggesting that the industry should move away from this traditional disinfection agent. However, the use of chlorine based sanitizers are presented as belonging to the most effective and efficient sanitizers when adequate doses are used. In this review improvements in water disinfection and sanitation strategies, including a shower pre-washing step and a final rinse of the produce, are suggested.

  7. Purification and partial characterization of haloperoxidase from fresh water algae Cladophora glomerata.

    PubMed

    Verdel, E F; Kline, P C; Wani, S; Woods, A E

    2000-02-01

    Many haloperoxidases have been purified from diverse organisms, including lichen, fungi, bacteria, and marine algae. In this study a haloperoxidase was purified from the fresh water algae, Cladophora glomerata, by homogenization and centrifugation, ammonium sulfate fractionation, ion-exchange and gel filtration chromatography. Molecular weight was determined by SDS-PAGE and by size exclusion HPLC and found to be approximately 43 kDa. The isoelectric point was determined to be approximately 8.1 by isoelectric focusing. The UV spectrum of the peroxidase showed a strong absorbance in the Soret band indicating a heme protein, unlike vanadium-dependent haloperoxidases from marine algae. Fresh water algal haloperoxidase catalyzed the iodination of tyrosine at a pH of 3.1. This haloperoxidase also catalyzes the oxidation of guaiacol and oxidation of iodide as well as catalyzing a peroxide-dependent reaction in both the presence and absence of chloride and bromide ions.

  8. Fresh water swimming as a risk factor for otitis externa: a case-control study.

    PubMed

    Springer, G L; Shapiro, E D

    1985-01-01

    A case-control study was conducted in which the amount and sites (fresh-water lakes and rivers, chlorinated pools, or the ocean) of recent swimming by 105 patients with otitis externa were compared with that of 239 controls. Swimming during the week prior to the visit was strongly associated with otitis externa. When the 80 cases and 127 controls with a history of recent swimming were compared, otitis externa was positively associated with the amount of swimming during the preceding week. Otitis externa was also positively associated with swimming in fresh water compared with ocean or pool swimming with the magnitude of this association being more pronounced at higher levels of exposure.

  9. Using Airborne Snow Observatory distributed snow water equivalent to predict seasonal inflow volumes and inform management decisions at the Hetch Hetchy Reservoir

    NASA Astrophysics Data System (ADS)

    Graham, C. B.; Painter, T. H.; Mazurkiewicz, A.

    2015-12-01

    Traditionally, estimates of seasonal streamflow volumes have been determined using statistical relationships to precipitation and snow depth measurements taken at widely spaced while geographically clustered gauges. While strong statistical relationships have been identified in some locations, these relationships are susceptible to breaking down during extreme conditions such as droughts or extremely wet years. The Airborne Snow Observatory (ASO) is a program where airplane mounted lidar is used to create snow-on and snow-off DEMs, yielding distributed estimates of snow water equivalent at the catchment scale. These estimates allow us, for the first time, to compare basin wide snow water equivalent to seasonal streamflow volumes. At the Tuolumne River basin in Yosemite National Park, Sierra Nevada Mountains, California, the ASO estimates of basin wide SWE are shown to be tightly correlated to seasonal streamflow volumes. These estimates are further improved when combined with precipitation measurements. These estimates appear to be more robust than traditional statistical methods, and have been used to improve predictions of inflows at the Hetch Hetchy Reservoir, the primary water source for the City and County of San Francisco and surrounding areas.

  10. Evaluation of Seven Sealer Systems for Metallized Zinc and Aluminum Coatings in Fresh and Salt Waters

    DTIC Science & Technology

    1992-09-01

    endorsement or approval of the use of such commercial products . The findings of this report are not to be construed as an official Department of the...immersion. The viscosity of this material may be easily reduced with a suitable thinner. The product applied in this study meets all current VOC restrictions...material for a variety of applicatiors including atmospheric weathering and fresh water immersion for steel and concrete substrates. The product is

  11. Detection of amount and activity of living algae in fresh water by dehydrogenase activity (DHA).

    PubMed

    Xie, Jun; Hu, Wenrong; Pei, Haiyan; Dun, Mina; Qi, Feng

    2008-11-01

    A study was performed to determine the amount and activity of living algae in fresh water by measuring the dehydrogenase activity (DHA) of algae in order to provide a method to assess the effect of algicide treatment. The conditions of measurement were researched with respect to incubating temperature and duration, and selection of extractants. The comparison between this method and an alternative method, chlorophyll a, shows that this method is simple and easy to practice, and can determine the effect of algicide treatment.

  12. Environmental Levels Of 129I Present In Bovine Thyroid And Fresh Water In Argentina

    SciTech Connect

    Negri, A. E.; Arazi, A.; Carnellia, P. F. F.; Barbara, E. de; Figueira, J. M.; Fimiani, L.; Heimanna, D. M.; Zalazara, L.; Fernandez Niello, J.; La Gamma, A. M.; Wallner, A.

    2010-08-04

    Concentrations of {sup 129}I in bovine thyroid and fresh water samples coming from all over Argentina were analyzed by Accelerator Mass Spectrometry (AMS) and total iodine present in samples by Gas Chromatography (GC) and Inductive Coupled Plasma Mass Spectrometry (ICP-MS), respectively. Once we complete this study, it will be the first set of data of this kind from an extended region of the south American subcontinent.

  13. Global Gray Water Footprint and Water Pollution Levels Related to Anthropogenic Nitrogen Loads to Fresh Water.

    PubMed

    Mekonnen, Mesfin M; Hoekstra, Arjen Y

    2015-11-03

    This is the first global assessment of nitrogen-related water pollution in river basins with a specification of the pollution by economic sector, and by crop for the agricultural sector. At a spatial resolution of 5 by 5 arc minute, we estimate anthropogenic nitrogen (N) loads to freshwater, calculate the resultant gray water footprints (GWFs), and relate the GWFs per river basin to runoff to calculate the N-related water pollution level (WPL) per catchment. The accumulated global GWF related to anthropogenic N loads in the period 2002-2010 was 13×10(12) m3/y. China contributed about 45% to the global total. Three quarters of the GWF related to N loads came from diffuse sources (agriculture), 23% from domestic point sources and 2% from industrial point sources. Among the crops, production of cereals had the largest contribution to the N-related GWF (18%), followed by vegetables (15%) and oil crops (11%). The river basins with WPL>1 (where the N load exceeds the basin's assimilation capacity), cover about 17% of the global land area, contribute about 9% of the global river discharge, and provide residence to 48% of the global population.

  14. Fresh Water Generation from Aquifer-Pressured Carbon Storage: Annual Report FY09

    SciTech Connect

    Wolery, T; Aines, R; Hao, Y; Bourcier, W; Wolfe, T; Haussman, C

    2009-11-25

    This project is establishing the potential for using brine pressurized by Carbon Capture and Storage (CCS) operations in saline formations as the feedstock for desalination and water treatment technologies including reverse osmosis (RO) and nanofiltration (NF). The aquifer pressure resulting from the energy required to inject the carbon dioxide provides all or part of the inlet pressure for the desalination system. Residual brine is reinjected into the formation at net volume reduction, such that the volume of fresh water extracted balances the volume of CO{sub 2} injected into the formation. This process provides additional CO{sub 2} storage capacity in the aquifer, reduces operational risks (cap-rock fracturing, contamination of neighboring fresh water aquifers, and seismicity) by relieving overpressure in the formation, and provides a source of low-cost fresh water to offset costs or operational water needs. This multi-faceted project combines elements of geochemistry, reservoir engineering, and water treatment engineering. The range of saline formation waters is being identified and analyzed. Computer modeling and laboratory-scale experimentation are being used to examine mineral scaling and osmotic pressure limitations. Computer modeling is being used to evaluate processes in the storage aquifer, including the evolution of the pressure field. Water treatment costs are being evaluated by comparing the necessary process facilities to those in common use for seawater RO. There are presently limited brine composition data available for actual CCS sites by the site operators including in the U.S. the seven regional Carbon Sequestration Partnerships (CSPs). To work around this, we are building a 'catalog' of compositions representative of 'produced' waters (waters produced in the course of seeking or producing oil and gas), to which we are adding data from actual CCS sites as they become available. Produced waters comprise the most common examples of saline

  15. Collagen scaffolds derived from fresh water fish origin and their biocompatibility.

    PubMed

    Pati, Falguni; Datta, Pallab; Adhikari, Basudam; Dhara, Santanu; Ghosh, Kuntal; Das Mohapatra, Pradeep Kumar

    2012-04-01

    Collagen, a major component of native extracellular matrix, has diverse biomedical applications. However, its application is limited due to lack of cost-effective production and risk of disease transmission from bovine sources currently utilized. This study describes fabrication and characterization of nano/micro fibrous scaffolds utilizing collagen extracted from fresh water fish origin. This is the first time collagen extracted from fresh water fish origin was studied for their biocompatibility and immunogenicity. The nano/micro fibrous collagen scaffolds were fabricated through self-assembly owing to its amphiphilic nature and were subsequently cross-linked. In vitro degradation study revealed higher stability of the cross-linked scaffolds with only ~50% reduction of mass in 30 days, while the uncross-linked one degraded completely in 4 days. Further, minimal inflammatory response was observed when collagen solution was injected in mice with or without adjuvant, without significant dilution of sera. The fish collagen scaffolds exhibited considerable cell viability and were comparable with that of bovine collagen. SEM and fluorescence microscopic analysis revealed significant proliferation rate of cells on the scaffolds and within 5 days the cells were fully confluent. These findings indicated that fish collagen scaffolds derived from fresh water origin were highly biocompatible in nature.

  16. [Accelerated senescence of fresh-cut Chinese water chestnut tissues in relation to hydrogen peroxide accumulation].

    PubMed

    Peng, Li-Tao; Jiang, Yue-Ming; Yang, Shu-Zhen; Pan, Si-Yi

    2005-10-01

    Accelerated senescence of fresh-cut Chinese water chestnut (CWC) tissues in relation to active oxygen species (AOS) metabolism was investigated. Fresh-cut CWC (2 mm thick) and intact CWC were stored at 4 degrees C in trays wrapped with plastic films. Changes in superoxide anion production rate, activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) were monitored, while contents of hydrogen peroxide, ascorbic acid, MDA as well as electrolyte leakage were measured. Fresh-cutting of CWC induced activities of SOD, CAT and APX to a certain extent (Fig. 2B and Fig. 3), but simultaneously stimulated superoxide anion production markedly (Fig. 2A), enhanced hydrogen peroxide accumulation and accelerated loss in ascorbic acid (Figs. 4 and 5), which resulted in increased lipid peroxidation indicated by malondialdehyde (MDA) content and electrolyte leakage (Fig. 1). Statistics analysis indicated that there was a significantly positive correlation among hydrogen peroxide accumulation, MDA content and electrolyte leakage (Table 1). Histochemical detection with 3, 3'-diaminobenzidine further demonstrated that hydrogen peroxide accumulation increased in fresh-cut CWC during storage (Fig. 5). AOS production rate and activities of SOD, CAT and APX changed little while no obvious hydrogen peroxide accumulation was observed, in intact CWC during storage.

  17. INFLUENCE OF FRESHWATER INFLOW AND WATER MANAGEMENT ON OYSTER-REEF RESIDENT ORGANISMS: IMPLICATIONS FOR ECOSYSTEM RESTORATION.

    EPA Science Inventory

    Two sources of seasonal programming are at work in southwest Florida estuaries: variation in temperature and variation in rainfall and water release resulting in downstream variations in salinity. Since more significant correlations were detected between salinity and metrics than...

  18. INFLUENCE OF FRESHWATER INFLOW AND WATER MANAGEMENT ON OYSTER-REEF RESIDENT ORGANISMS: IMPLICATIONS FOR ECOSYSTEM RESTORATION.

    EPA Science Inventory

    Two sources of seasonal programming are at work in southwest Florida estuaries: variation in temperature and variation in rainfall and water release resulting in downstream variations in salinity. Since more significant correlations were detected between salinity and metrics than...

  19. Decadal to millennial-scale variability in sea ice, primary productivity, and Pacific-Water inflow in the Chukchi/East Siberian Sea area (Arctic Ocean)

    NASA Astrophysics Data System (ADS)

    Stein, Ruediger; Fahl, Kirsten; Matthiessen, Jens; Méheust, Marie; Nam, Seung-il; Niessen, Frank; Schade, Inka; Schreck, Michael; Wassmuth, Saskia; Xiao, Xiaotong

    2014-05-01

    Sea-ice is an essential component of the global climate system and, especially, the Polar Oceans. An alarming decrease in term of sea-ice concentration, thickness and duration, has been observed in the Arctic Ocean and its marginal seas over the last 30 years. Thus, understanding the processes controlling modern sea-ice variability and reconstructing paleo-sea-ice extent and variability in polar regions have become of great interest for the international scientific community during the last years. Here, we present new proxy records determined in sediment cores from the East Siberian Sea (RV Polarstern Expedition ARK-XXIII/3 in 2008; Core PS72/350) and from the Chukchi Sea (RV Araon Expedition ARA2B in 2011; Core ARA2B-1A, -1B). These records, including organic-geochemical bulk parameters, specific biomarkers (IP25 and sterols; PIP25; for recent reviews see Stein et al., 2012; Belt and Müller, 2013), biogenic opal, mineralogical data as well as high-resolution XRF scanning data, give new insight into the short-term (decadal-, centennial- to millennial-scale) variability in sea-ice, primary productivity and Pacific-Water inflow during Holocene times. Maximum concentrations of phytoplankton biomarkers and biogenic opal were determined between 8.5 and 4 kyrs. BP, suggesting enhanced primary productivity triggered by increased inflow of nutrient-rich Pacific Water (and/or an increased nutrient input due to an ice-edge position). Short-lived peak values in productivity might be related to strong pulses of Pacific-Water input during this time period (cf., Ortiz et al., 2009). A seasonal sea-ice cover was present in the Chukchi Sea throughout the last 10 kyrs. During the last 3-4 kyrs. BP, the sea-ice cover significantly extended. References Belt, S.T. and Müller, J., 2013. The Arctic sea ice biomarker IP25: a review of current understanding, recommendations for future research and applications in palaeo sea ice reconstructions. Quaternary Science Review 73, 9-25. Ortiz

  20. Availability of fresh ground water, Montauk Point area, Suffolk County, Long Island, New York

    USGS Publications Warehouse

    Perlmutter, Nathaniel Matthew; DeLuca, Frank A.

    1963-01-01

    Ground water is the only source of supply at the Montauk Air Force Station n eastern Suffolk County. The water is contained in the upper 200 feet of deposits of late Pleistocene age, which are broadly divided into an upper unit of undifferentiated till and stratified drift and a lower unit of stratified drift. Fresh water in the principal aquifer, which is in the lower unit, is a lens-shaped body, which lies above salty water containing as much as 11,300 ppm of chloride. The fresh water is under artesian pressure and has a head ranging from about sea level to 3.5 feet above sea level. Pumping rates of 50 to 100 gpm cause salty water to move toward the. supply wells from below. The optimum pumping rate of most wells is about 30 gpm. New wells should be drilled as remote as possible from existing wells, and the well screens should be set as high above the zone of diffusion as the deposits permit.

  1. Hydrochemical reactions and origin of offshore relatively fresh pore water from core samples in Hong Kong

    NASA Astrophysics Data System (ADS)

    Kwong, Hiu Tung; Jiao, Jiu Jimmy

    2016-06-01

    The existence of relatively fresh pore water offshore has been well recognised over the globe but studies on the chemistry of the pore water from offshore geological formations are extremely limited. This study aims to characterize the hydrochemistry of the submarine groundwater body in Hong Kong. It looks into the major ion concentrations and the stable isotopic compositions of pore water extracted from core samples from an offshore 42.30-m vibrocore in the southwestern Hong Kong waters. A minimum Cl- level of about one-third of that in typical seawater was noted in the terrestrial sediments, suggesting the presence of offshore relatively fresh water. Unexpectedly high NH4+ levels are attributed to organic matter decomposition in the terrestrial sediments. The leaching of shells due to exposure of marine sediments at sea-level low stands raises the Mg2+ and Ca2+ concentrations. Base Exchange Indices show weak cation exchange reactions in which Na+ and K+ are released while Mg2+ and Ca2+ are adsorbed. Isotopic compositions of pore water reveal that the low-salinity water is probably the relic water sequestered in fluvial systems during relative sea-level low stands. Cores properly stored in a freezer for a long time has been used to study the pore water chemistry. For the first time, this study introduces an approach to correct the measured data by considering the possible evaporation effect during the transportation and storage of the samples. Corrections for evaporation were applied to the major ion concentrations and the stable isotopic compositions of pore water measured. It is found that the corrections determined by the Cl- mass balance approach are more reliable. The corrected measurements give more reasonable observations and hence allow sensible conclusions on the hydrochemical reactions and the origin of pore water.

  2. Prediction in Ungauged Basins (PUB) for estimating water availability during water scarcity conditions: rainfall-runoff modelling of the ungauged diversion inflows to the Ridracoli water supply reservoir

    NASA Astrophysics Data System (ADS)

    Toth, Elena

    2013-04-01

    The Ridracoli reservoir is the main drinking water supply reservoir serving the whole Romagna region, in Northern Italy. Such water supply system has a crucial role in an area where the different characteristics of the communities to be served, their size, the mass tourism and the presence of food industries highlight strong differences in drinking water needs. Its operation allows high quality drinking water supply to a million resident customers, plus a few millions of tourists during the summer of people and it reduces the need for water pumping from underground sources, and this is particularly important since the coastal area is subject also to subsidence and saline ingression into aquifers. The system experienced water shortage conditions thrice in the last decade, in 2002, in 2007 and in autumn-winter 2011-2012, when the reservoir water storage fell below the attention and the pre-emergency thresholds, thus prompting the implementation of a set of mitigation measures, including limitations to the population's water consumption. The reservoir receives water not only from the headwater catchment, closed at the dam, but also from four diversion watersheds, linked to the reservoir through an underground water channel. Such withdrawals are currently undersized, abstracting only a part of the streamflow exceeding the established minimum flows, due to the design of the water intake structures; it is therefore crucial understanding how the reservoir water availability might be increased through a fuller exploitation of the existing diversion catchment area. Since one of the four diversion catchment is currently ungauged (at least at the fine temporal scale needed for keeping into account the minimum flow requirements downstream of the intakes), the study first presents the set up and parameterisation of a continuous rainfall-runoff model at hourly time-step for the three gauged diversion watersheds and for the headwater catchment: a regional parameterisation

  3. Water budget and estimated suspended-sediment inflow for Reelfoot Lake, Obion and Lake Counties, Northwestern Tennessee, May 1984-April 1985

    USGS Publications Warehouse

    Robbins, Clarence H.

    1985-01-01

    Reelfoot Lake in northwestern Tennessee, with a surface area of 15,500 acres at normal pool elevation, is the largest natural lake in Tennessee. Over the years, the lake has become an important economic, environmental, and recreational resource to the people in the area, and to the State of Tennessee. The natural eutrophic succession rate of the lake has apparently been accelerated by land use practices within the Reelfoot Lake drainage basin during the past several decades. The potential loss of Reelfoot Lake has prompted the State to make management and restoration of the lake and its resources a priority objective. The U.S. Geological Survey entered into a cooperative study in May 1984 with the Tennessee Wildlife Resources Agency and the Tennessee Department of Health and Environment, Division of Water Management, to collect and analyze hydrologic data and prepare an annual water budget for Reelfoot Lake. The purpose of the water budget is to provide an analysis of the surface-groundwater-lake-atmospheric water relation at Reelfoot Lake. Results of the analysis can be used by lake managers to evaluate the potential effects of proposed lake management strategies upon the lake and surrounding hydrologic system. The water budget for the 12-month study period (May 1, 1984 through April 30, 1985) is presented in this report. In addition, estimates of suspended-sediment discharge from tributary streams in the Reelfoot Lake basin and an analysis of concentrations of constituents in stream-bottom material at three inflow sites are also presented. (Lantz-PTT)

  4. Resistance to fresh and salt water in intertidal mites (Acari: Oribatida): implications for ecology and hydrochorous dispersal.

    PubMed

    Pfingstl, Tobias

    2013-09-01

    The resistance to fresh water and seawater in three intertidal oribatid mite species from Bermuda, Alismobates inexpectatus, Fortuynia atlantica and Carinozetes bermudensis, was tested in laboratory experiments. Larvae are more sensitive to fresh and salt water, nymphs and adults showed equal tolerances. Fortuynia atlantica and A. inexpectatus were more resistant to salt water whereas C. bermudensis survived longer in fresh water. Differences in the resistance to fresh and salt water among the three species may be related to their different vertical occurrences in the eulittoral zone but also to the ability of single species to dwell in periodically brackish waters. In all three species half of the specimens survived at least 10 days in fresh water and more than 18 days in salt water. Maximal submersion time in fresh and salt water ranged from 40 to 143 days. Based on median lethal times it could be estimated that each species would be able to survive transport in seawater along the Gulf Stream over a distance of 3,000 km, from Central America to Bermuda. Thus hydrochorous dispersal should be assumed as the most likely mode of dispersal in intertidal fortuyniid and selenoribatid mites.

  5. Underwater Depth and Temperature Sensing Based on Fiber Optic Technology for Marine and Fresh Water Applications

    PubMed Central

    Duraibabu, Dinesh Babu; Leen, Gabriel; Toal, Daniel; Newe, Thomas; Lewis, Elfed; Dooly, Gerard

    2017-01-01

    Oceanic conditions play an important role in determining the effects of climate change and these effects can be monitored through the changes in the physical properties of sea water. In fact, Oceanographers use various probes for measuring the properties within the water column. CTDs (Conductivity, Temperature and Depth) provide profiles of physical and chemical parameters of the water column. A CTD device consists of Conductivity (C), Temperature (T) and Depth (D) probes to monitor the water column changes with respect to relative depth. An optical fibre-based point sensor used as a combined pressure (depth) and temperature sensor and the sensor system are described. Measurements accruing from underwater trials of a miniature sensor for pressure (depth) and temperature in the ocean and in fresh water are reported. The sensor exhibits excellent stability and its performance is shown to be comparable with the Sea-Bird Scientific commercial sensor: SBE9Plus. PMID:28555006

  6. Underwater Depth and Temperature Sensing Based on Fiber Optic Technology for Marine and Fresh Water Applications.

    PubMed

    Duraibabu, Dinesh Babu; Leen, Gabriel; Toal, Daniel; Newe, Thomas; Lewis, Elfed; Dooly, Gerard

    2017-05-27

    Oceanic conditions play an important role in determining the effects of climate change and these effects can be monitored through the changes in the physical properties of sea water. In fact, Oceanographers use various probes for measuring the properties within the water column. CTDs (Conductivity, Temperature and Depth) provide profiles of physical and chemical parameters of the water column. A CTD device consists of Conductivity (C), Temperature (T) and Depth (D) probes to monitor the water column changes with respect to relative depth. An optical fibre-based point sensor used as a combined pressure (depth) and temperature sensor and the sensor system are described. Measurements accruing from underwater trials of a miniature sensor for pressure (depth) and temperature in the ocean and in fresh water are reported. The sensor exhibits excellent stability and its performance is shown to be comparable with the Sea-Bird Scientific commercial sensor: SBE9Plus.

  7. Remote sensing of chlorophyll and temperature in marine and fresh waters.

    NASA Technical Reports Server (NTRS)

    Arvesen, J. C.; Millard, J. P.; Weaver, E. C.

    1973-01-01

    An airborne differential radiometer was demonstrated to be a sensitive, real-time detector of surface chlorophyll content in water bodies. The instrument continuously measures the difference in radiance between two wavelength bands, one centered near the maximum of the blue chlorophyll a absorption region and the other at a reference wavelength outside this region. Flights were made over fresh water lakes, marine waters, and an estuary, and the results were compared with 'ground truth' measurements of chlorophyll concentration. A correlation between output signal of the differential radiometer and the chlorophyll concentration was obtained. Examples of flight data are illustrated. Simultaneous airborne measurements of chlorophyll content and water temperature revealed that variations in chlorophyll are often associated with changes in temperature. Thus, simultaneous sensing of chlorophyll and temperature provides useful information for studies of marine food production, water pollution, and physical processes such as upwelling.

  8. Remote sensing of chlorophyll and temperature in marine and fresh waters.

    NASA Technical Reports Server (NTRS)

    Arvesen, J. C.; Millard, J. P.; Weaver, E. C.

    1973-01-01

    An airborne differential radiometer was demonstrated to be a sensitive, real-time detector of surface chlorophyll content in water bodies. The instrument continuously measures the difference in radiance between two wavelength bands, one centered near the maximum of the blue chlorophyll a absorption region and the other at a reference wavelength outside this region. Flights were made over fresh water lakes, marine waters, and an estuary, and the results were compared with 'ground truth' measurements of chlorophyll concentration. A correlation between output signal of the differential radiometer and the chlorophyll concentration was obtained. Examples of flight data are illustrated. Simultaneous airborne measurements of chlorophyll content and water temperature revealed that variations in chlorophyll are often associated with changes in temperature. Thus, simultaneous sensing of chlorophyll and temperature provides useful information for studies of marine food production, water pollution, and physical processes such as upwelling.

  9. Development of latent fingerprints on non-porous surfaces recovered from fresh and sea water.

    PubMed

    Madkour, Somaya; Abeer Sheta; El Dine, Fatma Badr; Elwakeel, Yasser; AbdAllah, Nermine

    2017-01-01

    Criminal offenders have a fundamental goal not to leave any traces at the crime scene. Some may suppose that items recovered underwater will have no forensic value, therefore, they try to destroy the traces by throwing items in water. These traces are subjected to the destructive environmental effects. This can represent a challenge for forensic experts investigating fingerprints. The present study was conducted to determine the optimal method for latent fingerprints development on dry non-porous surfaces submerged in aquatic environments at different time interval. The quality of the developed fingerprints depending on the used method was assessed. In addition, two factors were analyzed in this study; the effects of the nature of aquatic environment and the length of submerged time. Therefore, latent fingerprints were deposited on metallic, plastic and glass objects and submerged in fresh and sea water for 1, 2, and 10 days. After recovery, the items were processed by black powder, small particle reagent and cyanoacrylate fuming and the prints were examined. Each print was evaluated according to fingerprint quality assessment scale. Cyanoacrylate developed latent prints found to have the highest mean visibility score after submersion in fresh and sea water for 1, 2 and 10 days. Mean visibility score of prints developed showed significant decline after 10 days of submersion. Prints submerged in fresh water showed significantly higher mean visibility score than those submerged in sea water using various methods of development and in all time intervals. The study demonstrated that it is possible to recover latent prints submerged in water on different studied dry non porous surfaces with the best visualization method using cyanoacrylate either in fresh or sea water. The duration of submersion affects the quality of fingerprints developed; the longer the duration, the worse the quality is. In addition, this study has revealed that the exposure to high salinity i

  10. Delineating the physico-chemical, structural, and water characteristic changes during the deterioration of fresh noodles: Understanding the deterioration mechanisms of fresh noodles.

    PubMed

    Li, Man; Ma, Meng; Zhu, Ke-Xue; Guo, Xiao-Na; Zhou, Hui-Ming

    2017-02-01

    In this study, changes in fresh noodles during storage were evaluated at the physico-chemical, structural, and molecular levels. An increase in TPC and decrease in L(∗) value mostly occurred during the first 24h; the pH value significantly decreased (P<0.05) and proteins were partially depolymerized with the deterioration of fresh noodles, as evidenced by free amino acid determination and SDS-PAGE. Changes were also detected in the pasting and viscosity properties of the starch component. Moreover, the water sorption isotherm of fresh noodles decreased during storage, and the NMR transverse relaxation peak shifted right with an increased peak area between 10 and 100ms. MRI images showed that with increased storage time, the original structure was damaged and water distribution became non-uniform and migrated to the surface. TPC, pH, and L(∗) value were selected as the visualized parameters to characterize the fresh noodle deterioration, based on the correlation and factor analyses.

  11. Transcriptomic imprints of adaptation to fresh water: parallel evolution of osmoregulatory gene expression in the Alewife

    USGS Publications Warehouse

    Velotta, Jonathan P.; Wegrzyn, Jill L.; Ginzburg, Samuel; Kang, Lin; Czesny, Sergiusz J.; O'Neill, Rachel J.; McCormick, Stephen; Michalak, Pawel; Schultz, Eric T.

    2017-01-01

    Comparative approaches in physiological genomics offer an opportunity to understand the functional importance of genes involved in niche exploitation. We used populations of Alewife (Alosa pseudoharengus) to explore the transcriptional mechanisms that underlie adaptation to fresh water. Ancestrally anadromous Alewives have recently formed multiple, independently derived, landlocked populations, which exhibit reduced tolerance of saltwater and enhanced tolerance of fresh water. Using RNA-seq, we compared transcriptional responses of an anadromous Alewife population to two landlocked populations after acclimation to fresh (0 ppt) and saltwater (35 ppt). Our results suggest that the gill transcriptome has evolved in primarily discordant ways between independent landlocked populations and their anadromous ancestor. By contrast, evolved shifts in the transcription of a small suite of well-characterized osmoregulatory genes exhibited a strong degree of parallelism. In particular, transcription of genes that regulate gill ion exchange has diverged in accordance with functional predictions: freshwater ion-uptake genes (most notably, the ‘freshwater paralog’ of Na+/K+-ATPase α-subunit) were more highly expressed in landlocked forms, whereas genes that regulate saltwater ion secretion (e.g. the ‘saltwater paralog’ of NKAα) exhibited a blunted response to saltwater. Parallel divergence of ion transport gene expression is associated with shifts in salinity tolerance limits among landlocked forms, suggesting that changes to the gill's transcriptional response to salinity facilitate freshwater adaptation.

  12. Transcriptomic imprints of adaptation to fresh water: parallel evolution of osmoregulatory gene expression in the Alewife.

    PubMed

    Velotta, Jonathan P; Wegrzyn, Jill L; Ginzburg, Samuel; Kang, Lin; Czesny, Sergiusz; O'Neill, Rachel J; McCormick, Stephen D; Michalak, Pawel; Schultz, Eric T

    2017-02-01

    Comparative approaches in physiological genomics offer an opportunity to understand the functional importance of genes involved in niche exploitation. We used populations of Alewife (Alosa pseudoharengus) to explore the transcriptional mechanisms that underlie adaptation to fresh water. Ancestrally anadromous Alewives have recently formed multiple, independently derived, landlocked populations, which exhibit reduced tolerance of saltwater and enhanced tolerance of fresh water. Using RNA-seq, we compared transcriptional responses of an anadromous Alewife population to two landlocked populations after acclimation to fresh (0 ppt) and saltwater (35 ppt). Our results suggest that the gill transcriptome has evolved in primarily discordant ways between independent landlocked populations and their anadromous ancestor. By contrast, evolved shifts in the transcription of a small suite of well-characterized osmoregulatory genes exhibited a strong degree of parallelism. In particular, transcription of genes that regulate gill ion exchange has diverged in accordance with functional predictions: freshwater ion-uptake genes (most notably, the 'freshwater paralog' of Na(+) /K(+) -ATPase α-subunit) were more highly expressed in landlocked forms, whereas genes that regulate saltwater ion secretion (e.g. the 'saltwater paralog' of NKAα) exhibited a blunted response to saltwater. Parallel divergence of ion transport gene expression is associated with shifts in salinity tolerance limits among landlocked forms, suggesting that changes to the gill's transcriptional response to salinity facilitate freshwater adaptation.

  13. Surface-water and suspended-sediment inflow and outflow for Nutria Reservoir No 3, Zuni Indian Reservation, New Mexico, March 1994 to September 1995

    USGS Publications Warehouse

    Gellis, A.C.

    1998-01-01

    Surface-water and suspended-sediment inflow to and outflow from Nutria Reservoir No. 3 on the Zuni Indian Reservation, western New Mexico, were calculated. The period of study was March 3, 1994, to September 30, 1995. Total runoff into Nutria Reservoir No. 3 during the study period was 6,812 acre-feet. During the study period, 24,310 tons of suspended sediment was transported into Nutria Reservoir No. 3, and 259 tons of suspended sediment was transported out of Nutria Reservoir No. 3. Runoff during the study period, recorded at an upstream gage with 25 years of record, was 137 percent higher than that for a 19-month period similar to the study period. This may indicate that suspended-sediment loads transported into Nutria Reservoir No. 3 also were larger than average. Based on the difference between inflow and outflow of suspended sediment, 24,050 tons of suspended sediment was deposited in Nutria Reservoir No. 3. From March 1994 to May 1994 the spillway elevation of Nutria Reservoir No. 3 was raised to allow water to be diverted into an adjacent reservoir, Nutria Reservoir No. 4. This flow and sediment transported into Nutria Reservoir No. 4 were not recorded. If the elevation of the spillway had not been raised, suspended- sediment loads recorded downstream from Nutria Reservoir No. 3 would have been larger and the calculated amount of sediment deposited in Nutria Reservoir would have been smaller. Of the total suspended-sediment load entering Nutria Reservoir No. 3 during the study period, 94 percent was transported by an arroyo, Garcia Draw. Garcia Draw drains only 15 percent of the total drainage area of Nutria Reservoir No. 3 and contributed less than 5 percent of the total surface runoff to the reservoir. The average annual amount of sediment deposited in Nutria Reservoir No. 3 during the study was 15,355 tons. By using a dry-weight density of 99.4 pounds per cubic foot for the deposited sediment, the annual volume of sediment deposited in Nutria Reservoir

  14. Enhancing microbiological safety of fresh orange juice by fruit immersion in hot water and chemical sanitizers.

    PubMed

    Pao, S; Davis, C L

    1999-07-01

    Trials were conducted with hot water and chemicals to sanitize Valencia oranges contaminated by natural microflora or inoculated with Escherichia coli. Microbial loads and sensory quality of fresh juice extracted from surface-heated fruit were also evaluated. E. coli on fruit surfaces was reduced by either hot water or chemical treatments. An estimated 5-log reduction of E. coli was attained by immersing inoculated fruit in hot water at 80 degrees C for 1 min or 70 degrees C for 2 min. Immersing inoculated fruit in various chemical solutions at about 30 degrees C for 8 min only reduced E. coli by about 1.8- to 3.1-log cycles on nonstem-scar surfaces of the fruit. In general, both hot water and chemical treatments were less effective at removing microflora from the stem-scar area. Rapid hot-water immersions at 80 degrees C for 1 min and 70 degrees C for 2 min reduced both fruit-surface and initial juice microbial loads without altering original sensory quality of fresh juice.

  15. Advanced Membrane Filtration Technology for Cost Effective Recovery of Fresh Water from Oil & Gas Produced Brine

    SciTech Connect

    David B. Burnett

    2004-09-29

    Produced water is a major waste generated at the oil and natural gas wells in the state of Texas. This water could be a possible source of new fresh water to meet the growing demands of the state after treatment and purification. Treatment of brine generated in oil fields or produced water with an ultrafiltration membranes were the subject of this thesis. The characterization of ultrafiltration membranes for oil and suspended solids removal of produced water, coupled with the reverse osmosis (RO) desalination of brine were studied on lab size membrane testing equipment and a field size testing unit to test whether a viable membrane system could be used to treat produced water. Oil and suspended solids were evaluated using turbidity and oil in water measurements taken periodically. The research considered the effect of pressure and flow rate on membrane performance of produced water treatment of three commercially available membranes for oily water. The study also analyzed the flux through the membrane and any effect it had on membrane performance. The research showed that an ultrafiltration membrane provided turbidity removal of over 99% and oil removal of 78% for the produced water samples. The results indicated that the ultrafiltration membranes would be asset as one of the first steps in purifying the water. Further results on selected RO membranes showed that salt rejection of greater than 97% could be achieved with satisfactory flux and at reasonable operating cost.

  16. Observed vulnerability of Filchner-Ronne Ice Shelf to wind-driven inflow of warm deep water

    NASA Astrophysics Data System (ADS)

    Darelius, E.; Fer, I.; Nicholls, K. W.

    2016-08-01

    The average rate of melting at the base of the large Filchner-Ronne Ice Shelf in the southern Weddell Sea is currently low, but projected to increase dramatically within the next century. In a model study, melt rates increase as changing ice conditions cause a redirection of a coastal current, bringing warm water of open ocean origin through the Filchner Depression and into the Filchner Ice Shelf cavity. Here we present observations from near Filchner Ice Shelf and from the Filchner Depression, which show that pulses of warm water already arrive as far south as the ice front. This southward heat transport follows the eastern flank of the Filchner Depression and is found to be directly linked to the strength of a wind-driven coastal current. Our observations emphasize the potential sensitivity of Filchner-Ronne Ice Shelf melt rates to changes in wind forcing.

  17. Observed vulnerability of Filchner-Ronne Ice Shelf to wind-driven inflow of warm deep water

    PubMed Central

    Darelius, E.; Fer, I.; Nicholls, K. W.

    2016-01-01

    The average rate of melting at the base of the large Filchner-Ronne Ice Shelf in the southern Weddell Sea is currently low, but projected to increase dramatically within the next century. In a model study, melt rates increase as changing ice conditions cause a redirection of a coastal current, bringing warm water of open ocean origin through the Filchner Depression and into the Filchner Ice Shelf cavity. Here we present observations from near Filchner Ice Shelf and from the Filchner Depression, which show that pulses of warm water already arrive as far south as the ice front. This southward heat transport follows the eastern flank of the Filchner Depression and is found to be directly linked to the strength of a wind-driven coastal current. Our observations emphasize the potential sensitivity of Filchner-Ronne Ice Shelf melt rates to changes in wind forcing. PMID:27481659

  18. THE EFFECT OF FRESHWATER INFLOW ON NET ECOSYSTEM METABOLISM IN LAVACA BAY, TEXAS

    EPA Science Inventory

    Estuaries and other coastal ecosystems depend on freshwater inflow to maintain the gradients in environmental characteristics that define these transitional water bodies. Freshwater inflow (FWI) rates in many estuaries are changing due to changing land use patterns, water divers...

  19. THE EFFECT OF FRESHWATER INFLOW ON NET ECOSYSTEM METABOLISM IN LAVACA BAY, TEXAS

    EPA Science Inventory

    Estuaries and other coastal ecosystems depend on freshwater inflow to maintain the gradients in environmental characteristics that define these transitional water bodies. Freshwater inflow (FWI) rates in many estuaries are changing due to changing land use patterns, water divers...

  20. Water-pollution effects of metals on fresh-water fish. January 1980-October 1991 (Citations from the NTIS Data Base). Rept. for Jan 80-Oct 91

    SciTech Connect

    Not Available

    1991-10-01

    The bibliography contains citations concerning laboratory and field studies regarding effects of metals on fresh water fish. Topics include toxicity studies of specific species, bioaccumulation, and the distribution and fate of metals in fresh water bodies. Copper, chromium, cadmium, mercury, and zinc are among the metals considered. (Contains 175 citations with title list and subject index.)

  1. Assessing climate change impacts on fresh water resources of the Athabasca River Basin, Canada.

    PubMed

    Shrestha, Narayan Kumar; Du, Xinzhong; Wang, Junye

    2017-12-01

    Proper management of blue and green water resources is important for the sustainability of ecosystems and for the socio-economic development of river basins such as the Athabasca River Basin (ARB) in Canada. For this reason, quantifying climate change impacts on these water resources at a finer temporal and spatial scale is often necessary. In this study, we used a Soil and Water Assessment Tool (SWAT) to assess climate change impacts on fresh water resources, focusing explicitly on the impacts to both blue and green water. We used future climate data generated by the Canadian Center for Climate Modelling and Analysis Regional Climate Model (CanRCM4) with a spatial resolution of 0.22°×0.22° (~25km) for two emission scenarios (RCP 4.5 and 8.5). Results projected the climate of the ARB to be wetter by 21-34% and warmer by 2-5.4°C on an annual time scale. Consequently, the annual average blue and green water flow was projected to increase by 16-54% and 11-34%, respectively, depending on the region, future period, and emission scenario. Furthermore, the annual average green water storage at the boreal region was expected to increase by 30%, while the storage was projected to remain fairly stable or decrease in other regions, especially during the summer season. On average, the fresh water resources in the ARB are likely to increase in the future. However, evidence of temporal and spatial heterogeneity could pose many future challenges to water resource planners and managers. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  2. Finite-difference model to simulate the areal flow of saltwater and fresh water separated by an interface

    USGS Publications Warehouse

    Mercer, James W.; Larson, S.P.; Faust, Charles R.

    1980-01-01

    Model documentation is presented for a two-dimensional (areal) model capable of simulating ground-water flow of salt water and fresh water separated by an interface. The partial differential equations are integrated over the thicknesses of fresh water and salt water resulting in two equations describing the flow characteristics in the areal domain. These equations are approximated using finite-difference techniques and the resulting algebraic equations are solved for the dependent variables, fresh water head and salt water head. An iterative solution method was found to be most appropriate. The program is designed to simulate time-dependent problems such as those associated with the development of coastal aquifers, and can treat water-table conditions or confined conditions with steady-state leakage of fresh water. The program will generally be most applicable to the analysis of regional aquifer problems in which the zone between salt water and fresh water can be considered a surface (sharp interface). Example problems and a listing of the computer code are included. (USGS).

  3. Inflow Turbulence Generation Methods

    NASA Astrophysics Data System (ADS)

    Wu, Xiaohua

    2017-01-01

    Research activities on inflow turbulence generation methods have been vigorous over the past quarter century, accompanying advances in eddy-resolving computations of spatially developing turbulent flows with direct numerical simulation, large-eddy simulation (LES), and hybrid Reynolds-averaged Navier-Stokes-LES. The weak recycling method, rooted in scaling arguments on the canonical incompressible boundary layer, has been applied to supersonic boundary layer, rough surface boundary layer, and microscale urban canopy LES coupled with mesoscale numerical weather forecasting. Synthetic methods, originating from analytical approximation to homogeneous isotropic turbulence, have branched out into several robust methods, including the synthetic random Fourier method, synthetic digital filtering method, synthetic coherent eddy method, and synthetic volume forcing method. This article reviews major progress in inflow turbulence generation methods with an emphasis on fundamental ideas, key milestones, representative applications, and critical issues. Directions for future research in the field are also highlighted.

  4. Preliminary observation of complex salt-fresh water mixing in a beach aquifer.

    PubMed

    Thorn, Paul; Urish, Daniel

    2013-01-01

    Continuous observations of beach groundwater salinity over a 35-d period from a monitoring well established in the intertidal zone of a coastal harbor provided intriguing data on the interaction in the intertidal zone between the salt and fresh groundwater. During the monitoring period of the study, both semidiurnal variations and longer temporal trends in groundwater salinity were observed. The semidiurnal salinity variations were observed to occur nearly synchronously, but inconsistently with the tides. However, the salinity relationship with the tides was more complex, switching back and forth from being in-sync (higher salinities at high tide) to out-of-sync (higher salinities at low tide) a total of four times during the 35-d test period. The longer temporal trends showed chloride concentration (representing salinity) varying from as low as 50 mg/L to as high as 3600 mg/L over a period of between 9 to 12 d. The observations from the monitoring well reveal a complex pattern likely resulting from a combination of tidal pumping, density-induced convection, and changes in the terrestrial hydraulic gradient. However, these observations are based upon data from only one monitoring well, and are speculative at this point. A more thorough study of the complex fresh water-saline water relationship in the intertidal zone seems to have merit. © 2012, The Author(s). Ground Water © 2012, National Ground Water Association.

  5. A comparison of the coupled fresh water-salt water flow and the Ghyben-Herzberg sharp interface approaches to modeling of transient behavior in coastal aquifer systems

    USGS Publications Warehouse

    Essaid, H.I.

    1986-01-01

    A quasi-three dimensional finite difference model which simulates coupled, fresh water and salt water flow, separated by a sharp interface, is used to investigate the effects of storage characteristics, transmissivity, boundary conditions and anisotropy on the transient responses of such flow systems. The magnitude and duration of the departure of aquifer response from the behavior predicted using the Ghyben-Herzberg, one-fluid approach is a function of the ease with which flow can be induced in the salt water region. In many common hydrogeologic settings short-term fresh water head responses, and transitional responses between short-term and long-term, can only be realistically reproduced by including the effects of salt water flow on the dynamics of coastal flow systems. The coupled fresh water-salt water flow modeling approach is able to reproduce the observed annual fresh water head response of the Waialae aquifer of southeastern Oahu, Hawaii. ?? 1986.

  6. Reduction of pesticide residues on fresh vegetables with electrolyzed water treatment.

    PubMed

    Hao, Jianxiong; Wuyundalai; Liu, Haijie; Chen, Tianpeng; Zhou, Yanxin; Su, Yi-Cheng; Li, Lite

    2011-05-01

    Degradation of the 3 pesticides (acephate, omethoate, and dimethyl dichloroviny phosphate [DDVP]) by electrolyzed water was investigated. These pesticides were commonly used as broad-spectrum insecticides in pest control and high-residual levels had been detected in vegetables. Our research showed that the electrolyzed oxidizing (EO) water (pH 2.3, available chlorine concentration:70 ppm, oxidation-reduction potential [ORP]: 1170 mV) and the electrolyzed reducing (ER) water (pH 11.6, ORP: -860 mV) can reduce the pesticide residues effectively. Pesticide residues on fresh spinach after 30 min of immersion in electrolyzed water reduced acephate by 74% (EO) and 86% (ER), omethoate by 62% (EO) and 75% (ER), DDVP by 59% (EO) and 46% (ER), respectively. The efficacy of using EO water or ER water was found to be better than that of using tap water or detergent (both were reduced by more than 25%). Besides spinach, the cabbage and leek polluted by DDVP were also investigated and the degradation efficacies were similar to the spinach. Moreover, we found that the residual level of pesticide residue decreased with prolonged immersion time. Using EO or ER water to wash the vegetables did not affect the contents of Vitamin C, which inferred that the applications of EO or ER water to wash the vegetables would not result in loss of nutrition.

  7. [The Wormicidal Substances Of Fresh Water Fishes On Clonorchis Sinensis: II. Preliminary Research On The Wormicidal Substances From Mucous Substances Of Various Fresh Water Fishes

    PubMed

    Rhee, Jae Ku; Baek, Byeong Kirl; Ahn, Byung Zun; Park, Young Jun

    1980-06-01

    The present work which was investigated in July 1979, was to observe the wormicidal effects of the external mucous substances of 9 species of fresh water fishes (Cyprinus carpio, Parasilurus asotus, Anguilla japonica, Ophicephalus argus, Carassius carassius; golden crusian carp, Misgurnus anguillicaudatus, Zacco platypus, Pseudorasbora parva and Carassius carassius; crusian carp) on cercaria, liberated metacercaria and adult of Clonorchis sinensis. The mucous substances extracted by ether from the above 9 species of fishes were separated into many spots on the silica gel thin layer chromatography, and divided into many fractions in the silica gel column chromatography which used petroleum ether (30%) and chloroform (70%) as a solvent. 1. On the silica gel thin layer chromatography of ether extracts from 9 species of fresh water fishes, each of the Rf. values which had wormicidal effect on the cercaria of C. sinensis were different from others; Rf. value of C. carassius (crusian carp) was 0.937, 0.709 in O. argus, 0.612 in A. japonica, 0.576 in P. asotus, 0.451 in C. carpio, 0.701 in Z. platypus, 0.385 in C. carassius(golden crusian carp) and 0.15 in P. parva. Time for wormicide was different from each other, too. It took 14 min. in a case of C. carassius(crusian carp), 25 min. in Z. platypus, 26 min. in C. carassius(golden crusian carp), 28 min. in C. carpio, 30 min. in P. asotus, 35 min. in O. argus, 40 min. P. parva and 180 min. in A. japonica. But any of the spots of M. anguillicaudatus did not show wormicidal effect on the cercaria within 10 hours. 2. In the silica gel column chromatography of ether extracts from 9 species of fresh water fishes, the fractions which had wormicidal effect on the metacercaria of C. sienesis were different from each other; in a case of C. carassius(crusian carp), the first fraction only had wormicidal effect, the 2nd in P. asotus, the 3rd in O. argus, the 4th in C. carassius(golden crusian carp), the 2nd in C. carpio and the 4th in

  8. Decadal predictability of extreme fresh water export events from the Arctic Ocean into the Nordic Seas and subpolar North Atlantic

    NASA Astrophysics Data System (ADS)

    Schmith, Torben; Olsen, Steffen M.; Ringgaard, Ida M.; May, Wilhelm

    2016-04-01

    Abrupt fresh water releases originating in the Arctic Ocean have been documented to affect ocean circulation and climate in the North Atlantic area. Therefore, in this study, we investigate prospects for predicting such events up to one decade ahead. This is done in a perfect model setup by a combination of analyzing a 500 year control experiment and dedicated ensemble experiment aimed at predicting selected 10 year long segments of the control experiment. The selected segments are characterized by a large positive or negative trend in the total fresh water content in the Arctic Ocean. The analysis of the components (liquid fresh water and sea ice) reveals that they develop in a near random walk manner. From this we conclude that the main mechanism is integration of fresh water in the Beaufort Gyre through Ekman pumping from the randomly varying atmosphere. Therefore, the predictions from the ensemble experiments are on average not better than a damped persistence predictions. By running two different families of ensemble predictions, one starting from the 'observed' ocean globally, and one starting from climatology in the Arctic Ocean and from the observed ocean elsewhere, we conclude that the former outperforms the latter for the first few years as regards liquid fresh water and for the first year as regards sea ice. Analysis of the model experiments in terms of the fresh water export from the Arctic Ocean into Nordic seas and the subpolar North Atlantic reveals a very modest potential for predictability.

  9. Effect of hot water surface pasteurization of whole fruit on shelf life and quality of fresh-cut cantaloupe.

    PubMed

    Fan, X; Annous, B A; Beaulieu, J C; Sites, J E

    2008-04-01

    Cantaloupes are associated with recent outbreaks of foodborne illnesses and recalls. Therefore, new approaches are needed for sanitization of whole and cut fruit. In the present study, whole cantaloupes were submerged into water in the following 3 conditions: 10 degrees C water for 20 min (control), 20 ppm chlorine at 10 degrees C for 20 min, and 76 degrees C water for 3 min. Populations of microflora were measured on the rinds of the whole cantaloupes. Quality and microbial populations of fresh-cut cantaloupes prepared from whole fruit were analyzed after 1, 6, 8, 10, 13, 16, and 20 d of storage at 4 degrees C. The hot water significantly reduced both total plate count (TPC) and yeast and mold count on rind of whole fruits while chlorine or cold water wash did not result in a significant reduction of microbial population. Fresh-cut pieces prepared from hot water-treated cantaloupes had lower TPC than the other 2 treatments in the later storage periods (days 13 to 20) in 2 of 3 trials. The hot water treatment of whole fruits was inconsistent in reducing yeast and mold count of fresh-cut pieces. Soluble solids content, ascorbic acid content, fluid loss, and aroma and appearance scores were not consistently affected by either hot water or chlorine treatment. Our results suggested that hot water pasteurization of whole cantaloupes frequently resulted in lower TPCs of fresh-cut fruit during storage and did not negatively affect quality of fresh-cut cantaloupes.

  10. The effect of microwave power and heating time pretreatment on biogas production from fresh and dried water hyacinth (Eichhornia crassipes)

    NASA Astrophysics Data System (ADS)

    Sumardiono, Siswo; Budiyono, Mardiani, Dini Tri

    2015-12-01

    The objective of this research was to study the effect of microwave pretreatment of fresh and dried water hyacinth on biogas production. The variations of microwave power levels are 240; 400; 560 and 800 W. The variations of microwave heating time are 5; 7 and 9 min. The unpretreated fresh and dried water hyacinth are used as control. The result of research showed that almost all pretreated water hyacinth produced biogas were higher compare tounpretreated water hyacinth. The maximum of biogas production from fresh and dried water hyacinthwere obtained at 560 W for 7 min and 400 W for 7 min of microwave pretreatment. In this condition, pretreated fresh and dried water hyacinth resulted biogas production of 75,12 and 53,06 mL/g TS, respectively. The unpretreated fresh and dried water hyacinth produced biogas of 37,56 and 33,56 mL/g TS, respectively. The microwave pretreatment of water hyacinth improved biogas production. Microwave pretreatment had a positive impact on anaerobic biodegradability of water hyacinth.

  11. Optimization of hot water treatment for removing microbial colonies on fresh blueberry surface.

    PubMed

    Kim, Tae Jo; Corbitt, Melody P; Silva, Juan L; Wang, Dja Shin; Jung, Yean-Sung; Spencer, Barbara

    2011-08-01

    Blueberries for the frozen market are washed but this process sometimes is not effective or further contaminates the berries. This study was designed to optimize conditions for hot water treatment (temperature, time, and antimicrobial concentration) to remove biofilm and decrease microbial load on blueberries. Scanning electron microscopy (SEM) image showed a well-developed microbial biofilm on blueberries dipped in room temperature water. The biofilm consisted of yeast and bacterial cells attached to the berry surface in the form of microcolonies, which produced exopolymer substances between or upon the cells. Berry exposure to 75 and 90 °C showed little to no microorganisms on the blueberry surface; however, the sensory quality (wax/bloom) of berries at those temperatures was unacceptable. Response surface plots showed that increasing temperature was a significant factor on reduction of aerobic plate counts (APCs) and yeast/mold counts (YMCs) while adding Boxyl® did not have significant effect on APC. Overlaid contour plots showed that treatments of 65 to 70 °C for 10 to 15 s showed maximum reductions of 1.5 and 2.0 log CFU/g on APCs and YMCs, respectively; with acceptable level of bloom/wax score on fresh blueberries. This study showed that SEM, response surface, and overlaid contour plots proved successful in arriving at optima to reduce microbial counts while maintaining bloom/wax on the surface of the blueberries. Since chemical sanitizing treatments such as chlorine showed ineffectiveness to reduce microorganisms loaded on berry surface (Beuchat and others 2001, Sapers 2001), hot water treatment on fresh blueberries could maximize microbial reduction with acceptable quality of fresh blueberries. © 2011 Institute of Food Technologists®

  12. Fusion of Radarsat SAR and ETM+ imagery for identification of fresh water wetland

    NASA Astrophysics Data System (ADS)

    Ruan, Renzong; Feng, Xuezhi; She, Yuanjian

    2007-06-01

    The main aim of this paper was to identify inland fresh water wetland by using RADARSAT SAR data in combination with optical remote sensing data ETM+. The test area is a part of Hongze Lake, the fourth biggest fresh water lake in China, one of important wetlands for migratory birds in China. In this paper, two scenes of RADARSAT SAR data were acquired, one was obtained (incidence angle 39.1°) on July 9, 2003, another scene of SAR acquired on July 13, 2003(incidence angle 29.8 °). Optical remotely sensed data was Landsat ETM+ acquired on August 21, 2002. In order to explore the potential of Radarsat SAR data in the differentiation of different wetland types and wetland and upland types, two schemes were designed: one scheme was that Landsat ETM+ data and its derived data such as textural metrics were used to the classification of the study area; the other is that the Landsat ETM+ data, derived ancillary data and SAR data were used. CART algorithm was selected for the generation of decision rules, and the rules were applied to the classification of landuse/cover in the whole study area. The results showed that the combination of the SAR data and the optical remotely sensed data have achieved the highest classification accuracy (92.3% of total classification accuracy). The results also confirmed the value of classification tree in the identification of fresh water wetland. It was illustrated that radar data was a good data source for the identification of wetland.

  13. Five new species of yeasts from fresh water and marine habitats in the Florida Everglades.

    PubMed

    Fell, Jack W; Statzell-Tallman, Adele; Scorzetti, Gloria; Gutiérrez, Marcelo H

    2011-03-01

    Yeast populations in the Shark River Slough of the Florida Everglades, USA, were examined during a 3-year period (2002-2005) at six locations ranging from fresh water marshes to marine mangroves. Seventy-four described species (33 ascomycetes and 41 basidiomycetes) and an approximately equal number of undescribed species were isolated during the course of the investigation. Serious human pathogens, such as Candida tropicalis, were not observed, which indicates that their presence in coastal waters is due to sources of pollution. Some of the observed species were widespread throughout the fresh water and marine habitats, whereas others appeared to be habitat restricted. Species occurrence ranged from prevalent to rare. Five representative unknown species were selected for formal description. The five species comprise two ascomycetes: Candida sharkiensis sp. nov. (CBS 11368(T)) and Candida rhizophoriensis sp. nov. (CBS 11402(T)) (Saccharomycetales, Metschnikowiaceae), and three basidiomycetes: Rhodotorula cladiensis sp. nov. (CBS 10878(T)) in the Sakaguchia clade (Cystobasidiomycetes), Rhodotorula evergladiensis sp. nov. (CBS 10880(T)) in the Rhodosporidium toruloides clade (Microbotryomycetes, Sporidiobolales) and Cryptococcus mangaliensis sp. nov. (CBS 10870(T)) in the Bulleromyces clade (Agaricomycotina, Tremellales).

  14. Criteria for assessing the ecological risk of nonylphenol for aquatic life in Chinese surface fresh water.

    PubMed

    Zhang, Liangmao; Wei, Caidi; Zhang, Hui; Song, Mingwei

    2017-10-01

    The typical environmental endocrine disruptor nonylphenol is becoming an increasingly common pollutant in both fresh and salt water; it compromises the growth and development of many aquatic organisms. As yet, water quality criteria with respect to nonylphenol pollution have not been established in China. Here, the predicted "no effect concentration" of nonylphenol was derived from an analysis of species sensitivity distribution covering a range of species mainly native to China, as a means of quantifying the ecological risk of nonylphenol in surface fresh water. The resulting model, based on the log-logistic distribution, proved to be robust; the minimum sample sizes required for generating a stable estimate of HC5 were 12 for acute toxicity and 13 for chronic toxicity. The criteria maximum concentration and criteria continuous concentration were, respectively 18.49 μg L(-1) and 1.85 μg L(-1). Among the 24 sites surveyed, two were associated with a high ecological risk (risk quotient >1) and 12 with a moderate ecological risk (risk quotient >0.1). The potentially affected fraction ranged from 0.008% to 24.600%. The analysis provides a theoretical basis for both short- and long-term risk assessments with respect to nonylphenol, and also a means to quantify the risk to aquatic ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Methodology for modeling the migration of EOR chemicals in fresh water aquifers

    SciTech Connect

    Royce, B.; Garrell, M.; Kahn, A.; Kaplan, E.

    1983-11-01

    The objective of this study is to develop a method for modeling the transport of EOR chemicals accidentally released to fresh water aquifers. Six examples involving hypothetical releases of EOR chemicals at surrogate aquifer sites are used to illustrate the application of this method. Typical injection rates and concentrations of EOR chemicals used at current or proposed projects were obtained from the literature and used as the basis for the hypothetical accidents. Four surrogate aquifer sites were selected from States where chemical flooding methods are employed. Each site is based on real hydrological data but presented in such a way to avoid identification with existing EOR fields. A significant amount of data is required to model ground water systems. The hypothetical examples help to indicate the type of data needed. The computer results illustrate that high levels of contamination are possible for many years. In addition, due to these high levels of contamination, it is possible for contaminants to migrate offsite of the EOR field. There are a variety of pathways through which EOR chemicals could be accidentally released to fresh water aquifers during normal EOR operations. There is insufficient EOR experience to date, however, to forecast risks accurately. 119 references, 10 figures, 9 tables.

  16. Power Satellites, Carbon Dioxide, Synthetic Fuel, Sequestering Carbon as Synthetic Oil and Fresh Water from Seawater

    NASA Astrophysics Data System (ADS)

    Keith Henson, H.

    2010-05-01

    A small number of people have been working for the past year on ways to reduce the cost of power from space to the point that it could entirely displace fossil fuels and even put carbon dioxide back in empty oil fields as synthetic oil. The challenging part is reducing the cost of transport to GEO by a factor of ˜200 discussed in another paper in this volume. Given low cost power, synthetic fuels, carbon sequestration, and fresh water from seawater become economical.

  17. Circulation and transformation of Atlantic water in the Eurasian Basin and the contribution of the Fram Strait inflow branch to the Arctic Ocean heat budget

    NASA Astrophysics Data System (ADS)

    Rudels, Bert; Korhonen, Meri; Schauer, Ursula; Pisarev, Sergey; Rabe, Benjamin; Wisotzki, Andreas

    2015-03-01

    The inflows of Atlantic water from the Nordic Seas to the Arctic Ocean through Fram Strait and over the Barents Sea are examined and their pathways and transformations in the Eurasian Basin are described based primarily on hydrographic observations from two cruises with RV Polarstern in 2007 and 2011. The contrast between the high salinity Atlantic water core in the Nansen Basin and the lower Atlantic water salinity in the Amundsen Basin, combined with a salinity minimum below the Atlantic layer, suggest that the Fram Strait branch mainly remains in the Nansen Basin, while the Barents Sea branch continues along the continental slope, enters the Amundsen Basin and provides most of the Atlantic water in the Makarov and Canada basins. To examine the consequences of such a circulation pattern recently published estimates of the in- and outflows of volume and liquid freshwater through the Barents Sea, Bering Strait and the Canadian Arctic Archipelago as well as river runoff, net precipitation and ice export are reviewed and added together. To achieve volume and freshwater balances net outflows through Fram Strait of 2.3 Sv and 100 mSv respectively are required. This is reasonably close to the recently reported Fram Strait transport estimates. The net outflows are separated into two parts, upper layer transports, less dense than the entering Atlantic water, and lower layer transports, as dense as or denser than the Atlantic water. The largest net volume outflow occurs in the lower layer, 1.65 Sv, while the liquid freshwater is almost exclusively exported in the 0.64 Sv net outflow in upper layer, leading to unrealistically low salinities in the upper layer compared with observations. Atlantic water is north of Svalbard transformed into less saline surface water through melting of sea ice, which can supply the necessary higher salinity (halocline) water to the upper layer. 1.23 Sv of halocline water of salinity 34.2 must be added to obtain a more realistic salinity of 33

  18. Recovery of Fresh Water Resources from Desalination of Brine Produced During Oil and Gas Production Operations

    SciTech Connect

    David B. Burnett; Mustafa Siddiqui

    2006-12-29

    removal of hydrocarbons from produced water. The results of these experiments show that hydrocarbons from produced water can be reduced from 200 ppm to below 29 ppm level. Experiments were also done to remove the dissolved solids (salts) from the pretreated produced water using desalination membranes. Produced water with up to 45,000 ppm total dissolved solids (TDS) can be treated to agricultural water quality water standards having less than 500 ppm TDS. The Report also discusses the results of field testing of various process trains to measure performance of the desalination process. Economic analysis based on field testing, including capital and operational costs, was done to predict the water treatment costs. Cost of treating produced water containing 15,000 ppm total dissolved solids and 200 ppm hydrocarbons to obtain agricultural water quality with less than 200 ppm TDS and 2 ppm hydrocarbons range between $0.5-1.5 /bbl. The contribution of fresh water resource from produced water will contribute enormously to the sustainable development of the communities where oil and gas is produced and fresh water is a scarce resource. This water can be used for many beneficial purposes such as agriculture, horticulture, rangeland and ecological restorations, and other environmental and industrial application.

  19. Influence of water allocation and freshwater inflow on oyster production: a hydrodynamic-oyster population model for Galveston Bay, Texas, USA.

    PubMed

    Powell, Eric N; Klinck, John M; Hofmann, Eileen E; McManus, Margaret A

    2003-01-01

    A hydrodynamic-oyster population model was developed to assess the effect of changes in freshwater inflow on oyster populations in Galveston Bay, Texas, USA. The population model includes the effects of environmental conditions, predators, and the oyster parasite, Perkinsus marinus, on oyster populations. The hydrodynamic model includes the effects of wind stress, river runoff, tides, and oceanic exchange on the circulation of the bay. Simulations were run for low, mean, and high freshwater inflow conditions under the present (1993) hydrology and predicted hydrologies for 2024 and 2049 that include both changes in total freshwater inflow and diversions of freshwater from one primary drainage basin to another. Freshwater diversion to supply the Houston metropolitan area is predicted to negatively impact oyster production in Galveston Bay. Fecundity and larval survivorship both decline. Mortality from Perkinsus marinus increases, but to a lesser extent. A larger negative impact in 2049 relative to 2024 originates from the larger drop in fecundity under that hydrology. Changes in recruitment and mortality, resulting in lowered oyster abundance, occur because the bay volume available for mixing freshwater input from the San Jacinto and Buffalo Bayou drainage basins that drain metropolitan Houston is small in comparison to the volume of Trinity Bay that presently receives the bulk of the bay's freshwater inflow. A smaller volume for mixing results in salinities that decline more rapidly and to a greater extent under conditions of high freshwater discharge.Thus, the decline in oyster abundance results from a disequilibrium between geography and salinity brought about by freshwater diversion. Although the bay hydrology shifts, available hard substrate does not. The simulations stress the fact that it is not just the well-appreciated reduction in freshwater inflow that can result in decreased oyster production. Changing the location of freshwater inflow can also

  20. Comparison of formation mechanism of fresh-water and salt-water lacustrine organic-rich shale

    NASA Astrophysics Data System (ADS)

    Lin, Senhu

    2017-04-01

    Based on the core and thin section observation, major, trace and rare earth elements test, carbon and oxygen isotopes content analysis and other geochemical methods, a detailed study was performed on formation mechanism of lacustrine organic-rich shale by taking the middle Permian salt-water shale in Zhungaer Basin and upper Triassic fresh-water shale in Ordos Basin as the research target. The results show that, the middle Permian salt-water shale was overall deposited in hot and dry climate. Long-term reductive environment and high biological abundance due to elevated temperature provides favorable conditions for formation and preservation of organic-rich shale. Within certain limits, the hotter climate, the organic-richer shale formed. These organic-rich shale was typically distributed in the area where palaeosalinity is relatively high. However, during the upper Triassic at Ordos Basin, organic-rich shale was formed in warm and moist environment. What's more, if the temperature, salinity or water depth rises, the TOC in shale decreases. In other words, relatively low temperature and salinity, stable lake level and strong reducing conditions benefits organic-rich shale deposits in fresh water. In this sense, looking for high-TOC shale in lacustrine basin needs to follow different rules depends on the palaeoclimate and palaeoenvironment during sedimentary period. There is reason to believe that the some other factors can also have significant impact on formation mechanism of organic-rich shale, which increases the complexity of shale oil and gas prediction.

  1. Decarb/Desal: Separation of Carbon Dioxide from Flue Gas with Simultaneous Fresh Water Production

    SciTech Connect

    Aines, R; Bourcier, W

    2009-10-21

    If fossil fuels continue to be a major part of the world's energy supply, effective means must be developed to deal with the carbon emissions. Geologic sequestration of supercritical CO{sub 2} is expected to play a major role in mitigating this problem. Separating carbon dioxide from other gases is the most costly aspect of schemes for geologic sequestration. That cost is driven by the complexity and energy intensity of current chemical-stripping methods for separating carbon dioxide. Our experience in water treatment technology indicated that an entirely new approach could be developed, taking advantage of water's propensity to separate gases that ionize in water (like CO{sub 2}) from those that do not (like N{sub 2}). Even though water-based systems might not have the extreme selectivity of chemicals like substituted amines used in industrial systems today, they have the potential to tolerate NO{sub x}, SO{sub x}, and particulates while also producing clean drinking water as a valuable byproduct. Lower capital cost, broader range of applicability, environmental friendliness, and revenue from a second product stream give this approach the potential to significantly expand the worldwide application of carbon separation for geologic sequestration. Here we report results for separation of CO{sub 2} from flue gas by two methods that simultaneously separate carbon dioxide and fresh water: ionic pumping of carbonate ions dissolved in water, and thermal distillation. The ion pumping method dramatically increases dissolved carbonate ion in solution and hence the overlying vapor pressure of CO{sub 2} gas, allowing its removal as a pure gas. We have used two common water treatment methods to drive the ion pumping approach, reverse osmosis and electrodialysis to produce pure CO{sub 2}. This novel approach to increasing the concentration of the extracted gas permits new approaches to treating flue gas, because the slightly basic water used as the extraction medium is

  2. Waterborne Leptospirosis: Survival and Preservation of the Virulence of Pathogenic Leptospira spp. in Fresh Water.

    PubMed

    Andre-Fontaine, Genevieve; Aviat, Florence; Thorin, Chantal

    2015-07-01

    Many studies have implicated fresh water as a source of leptospirosis outbreaks. To estimate the survival and the preservation of the virulence of pathogenic Leptospira spp. maintained in water, we selected five still waters with various pH and mineral profiles. The water samples were artificially inoculated with a culture of a pathogenic strain belonging to serovar Icterohaemorrhagiae. Samples were stored for 20 months at 4, 20 or 30 °C. The survival and preservation of virulence of this pathogenic strain was estimated by subculturing these stored samples. After 14 and 20 months of storage, the strain Icterohaemorrhagiae was re-isolated, and its virulence was determined using an animal model. In these waters, the mean survival was 130 days for storage at 4 °C, 263 days at 20 °C, and 316 days at 30 °C. Unexpectedly, the mean survival was 344 days for a final pH < 7 and 129 days for pH ≥ 7. Moreover, the pathogenic strain remained fully virulent and was able to induce a lethal disease in gerbils even when the pH of the contaminated waters decreased to <6. These data showed that despite unfavourable storage conditions such as cold, nutrient-poor acidic waters, the survival and virulence of pathogenic Leptospira spp. was fully preserved over at least 20 months.

  3. Geochemistry of trace metals in a fresh water sediment: field results and diagenetic modeling.

    PubMed

    Canavan, R W; Van Cappellen, P; Zwolsman, J J G; van den Berg, G A; Slomp, C P

    2007-08-01

    Concentrations of Fe, Mn, Cd, Co, Ni, Pb, and Zn were determined in pore water and sediment of a coastal fresh water lake (Haringvliet Lake, The Netherlands). Elevated sediment trace metal concentrations reflect anthropogenic inputs from the Rhine and Meuse Rivers. Pore water and sediment analyses, together with thermodynamic calculations, indicate a shift in trace metal speciation from oxide-bound to sulfide-bound over the upper 20 cm of the sediment. Concentrations of reducible Fe and Mn decline with increasing depth, but do not reach zero values at 20 cm depth. The reducible phases are relatively more important for the binding of Co, Ni, and Zn than for Pb and Cd. Pore waters exhibit supersaturation with respect to Zn, Pb, Co, and Cd monosulfides, while significant fractions of Ni and Co are bound to pyrite. A multi-component, diagenetic model developed for organic matter degradation was expanded to include Zn and Ni dynamics. Pore water transport of trace metals is primarily diffusive, with a lesser contribution of bioirrigation. Reactions affecting trace metal mobility near the sediment-water interface, especially sulfide oxidation and sorption to newly formed oxides, strongly influence the modeled estimates of the diffusive effluxes to the overlying water. Model results imply less efficient sediment retention of Ni than Zn. Sensitivity analyses show that increased bioturbation and sulfate availability, which are expected upon restoration of estuarine conditions in the lake, should increase the sulfide bound fractions of Zn and Ni in the sediments.

  4. Laboratory Study on Water Uptake by Freshly Emitted Peat Smoke Particles in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Chen, J.; Kuwata, M.; Itoh, M.

    2015-12-01

    Tropical peatland burning activities in Southeast Asia, which can keep smouldering for a long time, have been becoming rather frequent during the last few decades. These combustions have released huge amounts of greenhouse gases and aerosol particles into the atmosphere, contributing large uncertainties to the global radiative forcing estimation. In addition, the gas and aerosol particles emitted from the peat-fire have caused environmental and human health issues. These regional and global impacts are closely tied to water uptake properties of aerosol particles, which alter their physical and chemical characteristics. However, hygroscopic property of peat burning aerosol particles has rarely been investigated. Here, we utilized a self-built Humidified Tandem Differential Mobility Analyzer (HTDMA) to measure diameter growth factors of fresh peat burning particles, which were generated during laboratory peat combustion experiments under controlled conditions. Particle number size distribution and chemical composition were also measured using a Scanning Mobility Particle Sizer (SMPS) and the Time of Flight - Aerosol Chemical Speciation Monitor (ToF-ACSM). Number size distribution demonstrated a bimodal pattern, with the mode diameters in the size ranges of 50-80 nm and 300-500 nm, respectively. The corresponding normalized volume size distribution was unimodal distributed with mode diameter at around 400-600nm. Water uptake of freshly emitted peat smoke aerosol particles was less hygroscopic, probably because fresh peat burning aerosol particles were predominantly composed of organic compounds and sulfates were negligible. The obtained information can be further applied into the studies on the influence of peat burning aerosol particles on regional and global climate.

  5. Reduction of organic trace compounds and fresh water consumption by recovery of advanced oxidation processes treated industrial wastewater.

    PubMed

    Bierbaum, S; Öller, H-J; Kersten, A; Klemenčič, A Krivograd

    2014-01-01

    Ozone (O(3)) has been used successfully in advanced wastewater treatment in paper mills, other sectors and municipalities. To solve the water problems of regions lacking fresh water, wastewater treated by advanced oxidation processes (AOPs) can substitute fresh water in highly water-consuming industries. Results of this study have shown that paper strength properties are not impaired and whiteness is slightly impaired only when reusing paper mill wastewater. Furthermore, organic trace compounds are becoming an issue in the German paper industry. The results of this study have shown that AOPs are capable of improving wastewater quality by reducing organic load, colour and organic trace compounds.

  6. The behavior of heavy metals in tidal flat sediments during fresh water leaching.

    PubMed

    Li, QuSheng; Liu, YaNan; Du, YeFeng; Cui, ZhiHong; Shi, Lei; Wang, LiLi; Li, HongJie

    2011-02-01

    Many of the coastal tidal flats in China that were polluted with heavy metals are now being reclaimed for arable land. The safety of these soils for agriculture is of great concern. The present study investigated the sediment chemical properties, concentrations, and speciation of heavy metals at different levels of desalination during a controlled leaching experiment. After leaching with fresh water, the average reductions in the heavy metal species examined in 0-65 cm depth sediment were 32.1% for Pb, 26.2% for Cd, 14.0% for Zn, 13.8% for Cu, and 11.0% for Cr, while the Ni concentration in sediment did not change significantly. The amounts of Cd, Pb, Cr, Cu, and Zn bound to the reducible fraction, the amounts of Cd, Pb, and Zn bound to the exchangeable fraction, the amounts of Pb, Cr, Cu, and Zn associated with the carbonate fraction, and the Cu associated with the oxidizable fraction all decreased significantly. Complexation with salt anions, ion exchange between the cations and the metal ions, removal of SO4(2-), dissolution of carbonate, and the redox potential variations all contributed to the decreases in Pb, Cd, Zn, Cu, and Cr. These results suggest that leaching with fresh water can also remove a fraction of the heavy metal contamination when it diminishes sediment salinity.

  7. [Sediment heavy metals quality criteria for fresh waters based on biological effect database approach].

    PubMed

    Zhang, Ting; Zhong, Wen-Jue; Zeng, Yi; Zhu, Ling-Yan

    2012-09-01

    Heavy metals are the important pollutants in sediments, which can cause serious damage to benthonic organisms and aquatic ecology, while biological effect database approach (BEDA) is a widely used method for assessing sediment quality in developed countries or regions. This paper introduced the concrete steps of this approach, and built the sediment quality criteria of five heavy metals (Cu, Zn, Cd, Pb, and Ni) for fresh waters. The comparability, reliability, and predictability of the criteria were also tested. It was shown that the threshold effect level (TEL) of the Cd, Ni, Pb, Zn, and Cu was 3.0, 31.4, 47.3, 74.9, and 45.5 mg x kg(-1) dry mass, and the probable effect level (PEL) of the Cd, Ni, Pb, Zn, and Cu was 19, 76.9, 204.1, 403.6, and 181.1 mg x kg(-1) dry mass basis, respectively. Except for Zn, the TEL and PEL for the Cu, Cd, Pb, and Ni were consistent with the definitional biological effect of the heavy metals, being accor-dance with the demands of sediment quality criteria for protecting benthic organisms and having high reliability, and thus, could be used as the proposed sediment quality criteria for fresh waters in China.

  8. Control of spoiler Pseudomonas spp. on fresh cut vegetables by neutral electrolyzed water.

    PubMed

    Pinto, Loris; Ippolito, Antonio; Baruzzi, Federico

    2015-09-01

    In the present study, we evaluated the antimicrobial activity of neutral electrolyzed water (NEW) against 14 strains of spoilage Pseudomonas of fresh cut vegetables under cold storage. The NEW, produced from solutions of potassium and sodium chloride, and sodium bicarbonate developed up to 4000 mg/L of free chlorine, depending on the salt and relative concentration used. The antimicrobial effect of the NEW was evaluated against different bacterial strains at 10(5) cells/ml, with different combinations of free chlorine concentration/contact time; all concentrations above 100 mg/L, regardless of the salt used, were found to be bactericidal already after 2 min. When catalogna chicory and lettuce leaves were dipped for 5 min in diluted NEW, microbial loads of mesophilic bacteria and Enterobacteriaceae were reduced on average of 1.7 log cfu/g. In addition, when lettuce leaves were dipped in a cellular suspension of the spoiler Pseudomonas chicorii I3C strain, diluted NEW was able to reduce Pseudomonas population of about 1.0 log cfu/g. Thanks to its high antimicrobial activity against spoilage microorganisms, and low cost of operation, the application of cycles of electrolysis to the washing water looks as an effective tool in controlling fresh cut vegetable microbial spoilage contamination occurring during washing steps. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Assessing Pesticide Contamination to Fresh Water in Some Agricultural Sites, Close to Oaxaca City, Mexico

    NASA Astrophysics Data System (ADS)

    Tomas, G.

    2002-12-01

    This study presents the results of a survey on pesticides in fresh water in shallow aquifers, rivers and dams in Zaachila, Tlacolula and Etla and agricultural valleys close to Oaxaca City, SW of Mexico. In the study zones, there are generalized uses of pesticides and the impact on the water resources by inadequate use of agricultural activities. Water is used for irrigation and drinking. Surveying criteria was to sample the aquifer (production wells), its water table (dig wells) and a regional water collector (Plan Benito Juarez Yuayapan dam). A total of 14 samples were analyzed for the identification and quantification of organochlorine and organophosphorous pesticides. Method was 508-EPA. Gas chromatographer was a 5890 series II Hewlett Packard, calibrated with several patterns. Results: 10 samples are contaminated with some pesticide of the used patterns; Dieldrin, Chlordano, Malathion, Mirex were not found; Traces of organophosphorus compounds were found in 8 samples, mainly Merphos, Parathion Ethylic and Disulfoton ; There was detected traces of world-forbidden insecticides as Metoxychlor, Parathion Ethylic and Disulfoton; and In one sample (Cuilapam well #1) DDT exceeds, the Mexican maximum limit for potable water (1 mg/l),

  10. DNA adducts in marine mussel and fresh water fishes living in polluted and unpolluted environments

    SciTech Connect

    Kurelec, B.; Checko, M.; Krca, S.; Garg, A.; Gupta, R.C. Baylor College of Medicine, Houston, TX )

    1988-09-01

    {sup 32}P-postlabeling analysis of DNA adducts in the digestive gland of marine mussel Mytilus galloprovincialis from polluted and unpolluted sites near Rovinj, Northern Adriatic, revealed that majority of adducts are caused by natural environmental factors rather than by man-made chemicals. The only pollutant-specific adducts were observed in a mussel exposed to seawater experimentally polluted with aminofluorene, and in a population of mussel living at a site heavily polluted with a waste waters of an oil refinery. Fresh water fish species Leuciscus cephalus, Barbus barbus, Abramis brama and Rutilus pigus virgo living in a polluted Sava River, Yugoslavia, or in its unpolluted tributary Korana River, have induced in their livers qualitatively identical and quantitatively similar DNA adducts. These DNA adducts had a species-specific patterns and their appearance was seasonally-dependent.

  11. Influence of fresh water, nutrients and DOC in two submarine-groundwater-fed estuaries on the west of Ireland.

    PubMed

    Smith, Aisling M; Cave, Rachel R

    2012-11-01

    Coastal fresh water sources, which discharge to the sea are expected to be directly influenced by climate change (e.g. increased frequency of extreme weather events). Sea-level rise and changes in rainfall patterns, changes in demand for drinking water and contamination caused by population and land use change, will also have an impact. Coastal waters with submarine groundwater discharge are of particular interest as this fresh water source is very poorly quantified. Two adjacent bays which host shellfish aquaculture sites along the coast of Co. Galway in the west of Ireland have been studied to establish the influence of fresh water inputs on nutrients and dissolved organic carbon (DOC) in each bay. Neither bay has riverine input and both are underlain by the karst limestone of the Burren and are susceptible to submarine groundwater discharge. Water and suspended matter samples were collected half hourly over 13 h tidal cycles over several seasons. Water samples were analysed for nutrients and DOC, while suspended matter was analysed for organic/inorganic content. Temperature and salinity measurements were recorded during each tidal station by SBE 37 MicroCAT conductivity/temperature sensors. Long-term mooring data were used to track freshwater input for Kinvara and Aughinish Bays and compare it with rainfall data. Results show that Kinvara Bay is much more heavily influenced by fresh water input than Aughinish Bay, and this is a strong source of fixed nitrogen to Kinvara Bay. Only during flood events is there a significant input of inorganic nitrogen from fresh water to Aughinish Bay, such as in late November 2009. Fresh water input does not appear to be a significant source of dissolved inorganic phosphate (DIP) to either bay, but is a source of DOC to both bays. C:N ratios of DOC/DON show a clear distinction between marine and terrestrially derived dissolved organic material.

  12. Mapping the Fresh-Salt Water Interaction in the Coastal Zone Using High Resolution Airborne Electromagnetics

    NASA Astrophysics Data System (ADS)

    Auken, E.; Pedersen, J. B. B.; Christiansen, A. V.; Foged, N.; Schaars, F.; Rolf, H.

    2016-12-01

    During the last decade airborne electromagnetics (AEM) and the accompanying data processing and inversion algorithms have undergone huge developments in terms of technology, costs, and reliability. This has expanded the scope of AEM from mainly mineral exploration to geotechnical applications and groundwater resource mapping. In this abstract we present a case with generally applicable results where AEM is used to map saltwater intrusion as well as outflow of fresh water to the sea. The survey took place on the Dutch coast in 2011 and is composed of a detailed inland coastal mapping as well as lines extending kilometres into the North Sea. It adds further complications that the area has a dense infrastructure and rapid varying dune topography causing the need for cautious data processing. We use the high resolution AEM system SkyTEM and data processing and inversion in the Aarhus Workbench. On the inland side, the results show a high resolution image of the fresh water interface and the interaction with clay layers acting as barriers. On the sea side they show a picture of freshwater plumes being pushed several hundred meters under the sea. The last mentioned information was actually the main purpose of the survey as this information could hardly be obtained by other methods and it is decisive for the total water balance of the system. The case shows an example of an AEM survey resulting in a high resolution image of the entire coastal zone. The technology is applicable in all coastal zones in the world and if applied it would lead to much improved management of the water resources in these landscapes.

  13. Numerical modelling and hydrochemical characterisation of a fresh-water lens in the Belgian coastal plain

    NASA Astrophysics Data System (ADS)

    Vandenbohede, A.; Lebbe, L.

    2002-05-01

    The distribution of fresh and salt water in coastal aquifers is influenced by many processes. The influence of aquifer heterogeneity and human interference such as land reclamation is illustrated in the Belgian coastal plain where, around A.D. 1200, the reclamation of a tidally influenced environment was completed. The aquifer, which was filled with salt water, was thereafter freshened. The areal distribution of peat, clay, silt and sand influences the general flow and distribution of fresh and salt water along with the drainage pattern and results in the development of fresh-water lenses. The water quality in and around the fresh-water lenses below an inverted tidal channel ridge is surveyed. The hydrochemical evolution of the fresh water lens is reconstructed, pointing to cation exchange, solution of calcite and the oxidation of organic material as the major chemical reactions. The formation and evolution of the fresh water lens is modelled using a two-dimensional density-dependent solute transport model and the sensitivity of drainage and conductivities are studied. Drainage level mainly influences the depth of the fresh-water lens, whereas the time of formation is mainly influenced by conductivity. Résumé. La répartition de l'eau douce et de l'eau salée dans les aquifères littoraux est influencée par de nombreux mécanismes. L'influence de l'hétérogénéité de l'aquifère et des interférences anthropiques telles que la mise en valeur des terres est illustrée par la plaine côtière belge où, depuis l'an 1200, on a mis en valeur un environnement soumis aux marées. L'aquifère, qui contenait de l'eau salée, contient maintenant de l'eau douce. La distribution spatiale de tourbe, d'argile, de silt et de sable joue un rôle dans l'écoulement général et dans la répartition de l'eau douce et de l'eau salée le long du réseau de drainage et produit des lentilles d'eau douce. La qualité de l'eau dans et autour des lentilles d'eau douce sous une lev

  14. Salt water and its relation to fresh ground water in Harris County, Texas

    USGS Publications Warehouse

    Winslow, Allen G.; Doyel, William Watson; Wood, L.A.

    1957-01-01

    Other less probable potential sources of salt-water contamination which are discussed include upward movement of salt water from below, vertical movement around salt domes or along faults, downward seepage from surface sources, and contamination through leaking wells.

  15. Effects of water extract of propolis on fresh shibuta (Barbus grypus) fillets during chilled storage.

    PubMed

    Duman, Muhsine; Özpolat, Emine

    2015-12-15

    The present study examined the effects of water extract of propolis on the chemical, microbiological and sensory quality in vacuum-packed fresh shibuta (Barbus grypus) fillets during storage at 2°C. Treatments in the study included the following: control (P0) without extract of propolis, 0.1 (P1), 0.3 (P3) and 0.5 (P5) % (v/w) the water extract of propolis, respectively. After 24 days of storage, the total volatile basic nitrogen (TVB-N) values were 57.76, 44.66, 42.23 and 36.5mg/100g, and total viable counts (TVC) were 8.9, 8.3, 7.96 and 6.95logcfu/g, for water extract of propolis additions of 0.1 (P1), 0.3 (P3), 0.5 (P5) and 0 (control; P0) % (v/w), respectively. The highest acceptable TVB-N value was adopted as 30 mg/100g, corresponding to shelf lives of 9, 15, 18 and 21 days for P0, P1, P3 and P5, respectively. Addition of 0.1% water extract of propolis extended the product's shelf-life by approximately 6 days, whereas the 0.5% water extract of propolis resulted in a significant shelf-life extension of the shibuta fillets, i.e. by approximately 12 days, according to sensory data, as compared to the control sample.

  16. Method validation for norovirus detection in naturally contaminated irrigation water and fresh produce.

    PubMed

    El-Senousy, Waled Morsy; Costafreda, M Isabel; Pintó, Rosa M; Bosch, Albert

    2013-10-01

    Human enteric viruses are shed in extremely high numbers in the feces of infected individuals, becoming environmental contaminants and eventually leading to contamination of a variety of foodstuffs at the pre-harvest stage. Among these foods at risk is fresh produce and irrigation water is a major vehicle for crop contamination. In the present study, a standardized molecular method for quantitative virus assay has been evaluated in different types of fresh produce and in irrigation water for human norovirus (NoV) detection. Two different virus concentration procedures, polyethylene-glycol precipitation (PEG) and organic flocculation (OF), were employed. The procedures were initially assayed in spiked samples and later validated on naturally contaminated samples from the Nile Delta in Egypt. Overall, PEG provided significantly (p<0.05) better virus recoveries than OF for both irrigation water and salad vegetable virus analysis. NoV GI and GII recoveries in spiked irrigation water ranged from 22.0% to 43.3% and from 12.6% to 16.4% with the PEG and OF methods, respectively. In experimentally contaminated salad vegetables, virus recoveries ranged from 28.0% to 48.0% and from 14.0% to 18.8% by PEG precipitation and OF, respectively. Using PEG precipitation, NoV was found in 31.9% of naturally contaminated irrigation water samples. Both NoV GI and GII were detected in these samples with genome copy numbers of around 10(2) per liter. Virus analyses performed in naturally contaminated fresh produce that included green onion, watercress, radish, leek, and lettuce show that NoV GI was present in 20.8%-34.0% of the samples with genome copy numbers of around 10(2) per gram. When OF was employed, NoV was found in 25.0% of the irrigation water samples. Both genogroups could be found in these samples with genome copy numbers of around 10 per liter. In fresh produce, GI was present in 16.0%-25.7% of the samples with genome copy numbers per gram of around 10. Surprisingly, NoV GII

  17. County fresh-water withdrawal water use allocated to relevant land uses in the United States: 1985 to 2010

    USGS Publications Warehouse

    Falcone, James

    2016-01-01

    This product is a series of six national 1-kilometer (km) raster datasets, for five year intervals between 1985 and 2010, representing USGS Water Use "Total Fresh Water Withdrawals", allocated to areas of land use representing anthropogenic use. Pixels representing anthropogenic uses (urban, agriculture, and mining land uses) are derived from the NAWQA Wall-to-wall Anthropogenic Land-use Trends (NWALT) product (Falcone, 2015), a series of decadal national raster datasets for the period 1974-2012. The raster datasets created here are intended as a source of information for estimating water use for watersheds, at the scale of HUC12 watersheds and coarser. Units are millions of gallons per day (mgd) per square km.

  18. Interaction between Fresh and Sea Water in Tidal Influenced Navigation Channel

    NASA Astrophysics Data System (ADS)

    Hwang, J. H. H.; Nam-Hoon, K.

    2016-02-01

    Nam-Hoon, Kim 1, Jin-Hwan, Hwang 2, Hyeyun-Ku 31,2,3 Department of Civil and Environmental Engineering, Seoul National University, Republic of Korea; 1nhkim0426@snu.ac.kr; 2jinhwang@snu.ac.kr; 3hyeyun.ku@gmail.com; We have conducted field observations after freshwater discharges of sea dike during ebb tide in Geum River Estuary, Korea to understand the interaction between fresh and sea water. To measure spatial variability of the stratified flow, an Acoustic Doppler Current Profiler (ADCP) and a portable free-fall tow-yo instrument, Yoing Ocean Data Acquisition Profiler (YODA profiler) which can continuously measures three-dimensional velocity profiles and vertical profiles of the fine-scale features, respectively, within water column were used in a vessel moving at a speed of 1-2 m/s. The flow observations show the strong stratification and dispersion occurred near field region because of the ebb tide advection (Fig. 1). As moving toward the far field region, the stratification and dispersion was getting thin and weak but still remaining. The presence of mixing process between fresh and sea water was represented by the gradient Richardson Number. The mixing occurred throughout the near field region and potentially mixed in the far field region. This study have been conducted to serve as a basic research of understanding the Region Of Freshwater Influence (ROFI) in the tidal influenced navigation channel. We are going to perform a few more observations in the future. Key words: Richardson number, stratification, mixing, ROFI, ADCP, CTDFigure 1. High-resolution observation data of salinity (psu) from YODA Profiler Acknowledgement: This research was supported by grants from the Korean Ministry of Oceans and Fisheries entitled as "Developing total management system for the Keum river estuary and coast" and "Integrated management of marine environment and ecosystems around Saemangeum". We also thank to the administrative supports of Integrated Research Institute of

  19. The deglaciation over Laurentian Fan: History of diatoms, IRD, ice and fresh water

    NASA Astrophysics Data System (ADS)

    Gil, Isabelle M.; Keigwin, Lloyd D.; Abrantes, Fatima

    2015-12-01

    A high-resolution diatom census coupled with other proxy data from Laurentian Fan (LF) provides a detailed description of the last deglaciation, bringing new insight to that period by revealing directly the timing of sea-ice formation and melting. Cold events Heinrich Event 1 (H1) and the Younger Dryas (YD) were multiphase events. H1 (∼16.8-15.7 cal kyr BP) was defined by a two-pulse release of icebergs promoting sea-ice formation. Melting of sea-ice after H1 corresponds to a cold and fresh anomaly that may have kept the Bølling colder than the Allerød. At ∼13.6 cal kyr BP, a cooling trend culminated with sea-ice formation, marking the YD onset (∼12.8 cal kyr BP). The decrease in sea-ice (∼12.2 cal kyr BP) led to a YD second phase characterized by very cold winters. However, the contribution of warm water diatoms tends to increase at the same time and the YD gradual end (∼11.6 cal kyr BP) contrasts with its abrupt end in Greenland ice cores. The YD cannot be regarded as an event triggered by a fresh water input through the Laurentian Channel since only one weak brief input nearly 1000 yrs after its onset is recorded. Very cold and cool conditions without ice mark the following Preboreal. A northward heat flux between 10.8 and 10.2 cal kyr BP was interrupted by the increased influence of coastal waters likely fed by inland melting. There was no further development of sea-ice or ice-drift then.

  20. Water from land - fresh water outflow from glaciated and non-glaciated catchments into the Hornsund fjord, Svalbard

    NASA Astrophysics Data System (ADS)

    Nawrot, Adam; Wawrzyniak, Tomasz; Walczowski, Waldemar; Osuch, Marzena

    2016-04-01

    Freshwater processes in South Spitsbergen catchments are facing climate related alterations and issues, such as prolongation of the ablation seasons, water level changes and droughts. Snow accumulation and duration of snow cover in high latitude areas largely determine hydrological and periglacial processes, influencing flora, fauna and their ecology. Hydrological data from this part of the Arctic so far were sparse and major gaps remained in our understanding of freshwater distribution, regime, status and threats. From 2013 to 2015 as part of multidisciplinary and complex investigations within the framework of "AWAKE2 - Arctic Climate System Study of Ocean, Sea Ice and Glaciers Interactions in Svalbard Area" project, field measurements were conducted around Hornsund, the southernmost fjord of Spitsbergen. This was the first study of the fresh water and snow cover in such scale in this area and included spatial distribution of snow, together with water balance measurements in non-glaciated and glaciated catchments. During the fieldwork in Hornsund Fjord area, snow thickness and snow density have been measured in 350 and 50 points, respectively. Precipitation was measured in 6 points. Runoff was measured on 7 rivers in different glaciated (Ariedalen, Sofiedalen, Lorchbreen, Bautabreen, Gashamna) and non-glaciated (Fuglebekken, Lisbetdalen) catchments. Meteorological observations were conducted at the Hornsund Polish Polar Station and in the in the surroundings of Hornsund fjord. The results of this investigation show response of the freshwater hydrological processes to observed seasonal climatic variations in this area. Approximated water balance and known volume of fresh water outflow to the sea are the key components of understanding Arctic fjord ecosystem mechanisms. This is the first comprehensive investigation of the water balance in this region. Project AWAKE2 is funded by Norway Grants.

  1. Acid precipitation: effects on fresh-water ecosystems. January 1978-September 1988 (Citations from the Life Sciences Collection data base). Report for January 1978-September 1988

    SciTech Connect

    Not Available

    1988-10-01

    This bibliography contains citations concerning the effects of acidification of fresh-water ecosystems. Algae and diatom distribution, survival, and reproduction rates of specific fish species under acid-lake conditions, and tolerance to stress caused by acidic conditions in fresh water ecosystems are studied. Effects of water ph on trace metal toxicity to fresh water organisms is briefly considered. Control and reduction of acidification is excluded from this bibliography. (Contains 290 citations fully indexed and including a title list.)

  2. Radial Inflow Turboexpander Redesign

    SciTech Connect

    William G. Price

    2001-09-24

    Steamboat Envirosystems, LLC (SELC) was awarded a grant in accordance with the DOE Enhanced Geothermal Systems Project Development. Atlas-Copco Rotoflow (ACR), a radial expansion turbine manufacturer, was responsible for the manufacturing of the turbine and the creation of the new computer program. SB Geo, Inc. (SBG), the facility operator, monitored and assisted ACR's activities as well as provided installation and startup assistance. The primary scope of the project is the redesign of an axial flow turbine to a radial inflow turboexpander to provide increased efficiency and reliability at an existing facility. In addition to the increased efficiency and reliability, the redesign includes an improved reduction gear design, and improved shaft seal design, and upgraded control system and a greater flexibility of application

  3. Biological differences between brackish and fresh water-derived Aedes aegypti from two locations in the Jaffna peninsula of Sri Lanka and the implications for arboviral disease transmission.

    PubMed

    Ramasamy, Ranjan; Jude, Pavilupillai J; Veluppillai, Thabothiny; Eswaramohan, Thampoe; Surendran, Sinnathamby N

    2014-01-01

    The mainly fresh water arboviral vector Aedes aegypti L. (Diptera: Culicidae) can also undergo pre-imaginal development in brackish water of up to 15 ppt (parts per thousand) salt in coastal areas. We investigated differences in salinity tolerance, egg laying preference, egg hatching and larval development times and resistance to common insecticides in Ae. aegypti collected from brackish and fresh water habitats in Jaffna, Sri Lanka. Brackish water-derived Ae. aegypti were more tolerant of salinity than fresh water-derived Ae. aegypti and this difference was only partly reduced after their transfer to fresh water for up to five generations. Brackish water-derived Ae. aegypti did not significantly discriminate between 10 ppt salt brackish water and fresh water for oviposition, while fresh water-derived Ae. aegypti preferred fresh water. The hatching of eggs from both brackish and fresh water-derived Ae. aegypti was less efficient and the time taken for larvae to develop into pupae was prolonged in 10 ppt salt brackish water. Ae. aegypti isolated from coastal brackish water were less resistant to the organophosphate insecticide malathion than inland fresh water Ae. aegypti. Brackish and fresh water-derived Ae. aegypti however were able to mate and produce viable offspring in the laboratory. The results suggest that development in brackish water is characterised by pertinent biological changes, and that there is restricted genetic exchange between coastal brackish and inland fresh water Ae. aegypti isolates from sites 5 km apart. The findings highlight the need for monitoring Ae. aegypti developing in coastal brackish waters and extending vector control measures to their habitats.

  4. Biological Differences between Brackish and Fresh Water-Derived Aedes aegypti from Two Locations in the Jaffna Peninsula of Sri Lanka and the Implications for Arboviral Disease Transmission

    PubMed Central

    Ramasamy, Ranjan; Jude, Pavilupillai J.; Veluppillai, Thabothiny; Eswaramohan, Thampoe; Surendran, Sinnathamby N.

    2014-01-01

    The mainly fresh water arboviral vector Aedes aegypti L. (Diptera: Culicidae) can also undergo pre-imaginal development in brackish water of up to 15 ppt (parts per thousand) salt in coastal areas. We investigated differences in salinity tolerance, egg laying preference, egg hatching and larval development times and resistance to common insecticides in Ae. aegypti collected from brackish and fresh water habitats in Jaffna, Sri Lanka. Brackish water-derived Ae. aegypti were more tolerant of salinity than fresh water-derived Ae. aegypti and this difference was only partly reduced after their transfer to fresh water for up to five generations. Brackish water-derived Ae. aegypti did not significantly discriminate between 10 ppt salt brackish water and fresh water for oviposition, while fresh water-derived Ae. aegypti preferred fresh water. The hatching of eggs from both brackish and fresh water-derived Ae. aegypti was less efficient and the time taken for larvae to develop into pupae was prolonged in 10 ppt salt brackish water. Ae. aegypti isolated from coastal brackish water were less resistant to the organophosphate insecticide malathion than inland fresh water Ae. aegypti. Brackish and fresh water-derived Ae. aegypti however were able to mate and produce viable offspring in the laboratory. The results suggest that development in brackish water is characterised by pertinent biological changes, and that there is restricted genetic exchange between coastal brackish and inland fresh water Ae. aegypti isolates from sites 5 km apart. The findings highlight the need for monitoring Ae. aegypti developing in coastal brackish waters and extending vector control measures to their habitats. PMID:25170879

  5. Advanced Membrane Filtration Technology for Cost Effective Recovery of Fresh Water from Oil & Gas Produced Brine

    SciTech Connect

    David B. Burnett

    2005-09-29

    This study is developing a comprehensive study of what is involved in the desalination of oil field produced brine and the technical developments and regulatory changes needed to make the concept a commercial reality. It was originally based on ''conventional'' produced water treatment and reviewed (1) the basics of produced water management, (2) the potential for desalination of produced brine in order to make the resource more useful and available in areas of limited fresh water availability, and (3) the potential beneficial uses of produced water for other than oil production operations. Since we have begun however, a new area of interest has appeared that of brine water treatment at the well site. Details are discussed in this technical progress report. One way to reduce the impact of O&G operations is to treat produced brine by desalination. The main body of the report contains information showing where oil field brine is produced, its composition, and the volume available for treatment and desalination. This collection of information all relates to what the oil and gas industry refers to as ''produced water management''. It is a critical issue for the industry as produced water accounts for more than 80% of all the byproducts produced in oil and gas exploration and production. The expense of handling unwanted waste fluids draws scarce capital away for the development of new petroleum resources, decreases the economic lifetimes of existing oil and gas reservoirs, and makes environmental compliance more expensive to achieve. More than 200 million barrels of produced water are generated worldwide each day; this adds up to more than 75 billion barrels per year. For the United States, the American Petroleum Institute estimated about 18 billion barrels per year were generated from onshore wells in 1995, and similar volumes are generated today. Offshore wells in the United States generate several hundred million barrels of produced water per year. Internationally

  6. Evaluations of global land-to-oceans fresh water discharge and evapotranspiration

    NASA Astrophysics Data System (ADS)

    Seo, K.; Waliser, D. E.; Tian, B.; Famiglietti, J.; Syed, T.

    2007-12-01

    We estimate global fresh water discharge from land to oceans (R) and evapotranspiration (ET) on monthly time scales using a number of complimentary hydrologic data sets. This estimate is possible due to the new capability of measuring oceanic and land water mass changes (dSo/dt,dSl/dt) from GRACE as well as the space-based measurements of oceanic and land precipitation (Po,Pl) and oceanic evaporation (Eo). R can be estimated through the water balance equation over oceans, R=Eo-Po-dSo/dt, and then ET is estimated based on water mass balance over land, ET=Pl-R-dSl/dt. Monthly time series of R show peaks in July and December, and those of ET shows peaks in March and August. In general, our estimates of R and ET are correlated with Pl well indicating qualitatively that our estimates capture temporal patterns of R and ET reasonably. We compare our estimation for R and ET to 20th century simulations from the WCRP CMIP3 multi-model archive that are assessed in the IPCC 4th Assessment Report. R and ET from AOGCMs mainly show annual cycles, but those estimated in this study exhibit additional semi-annual changes. The estimates of R and ET examined in this study are potentially useful to constraint current AOGCMs models.

  7. The Renewal of Fresh Water Through Treatment Wetlands: A Global Model

    NASA Astrophysics Data System (ADS)

    Bradford, M.; Fraser, L.; Steer, D.

    2001-05-01

    We present a global model that incorporates population growth, freshwater supply, dam construction, and, most importantly, an estimate of the returns of freshwater by the treatment of wastewater through wetlands. By including treatment wetlands within the global hydrological cycle, we estimate that humans can reduce the annual appropriation of freshwater in 2025 to 52%, even with the assumption that per capita rate of water use is increasing. The diminishing world supply and availability of freshwater is forcing a general re-assessment of freshwater use and the treatment of wastewater. Even with an increase in the construction of dams, the rate of population growth and the projected amount of future water use far surpasses the rate of supply. An earlier global model estimated that humans appropriated 52% of the annual accessible freshwater in 1990, and would appropriate at least 72% in 2025. This alarming figure is actually a very conservative estimate considering that the per capita rate of increase of water use is increasing. If per capita rate of increase was accounted for in the model, 99% of accessible freshwater will be appropriated in 2025. The use of constructed and natural wetlands for the treatment of wastewater may be an effective worldwide tool to help address the problem of fresh water availability.

  8. Interaction of a fresh water lake and a karstic spring via a syncline fold.

    PubMed

    Rezaei, Abolfazl; Zare, Mohammad; Raeisi, Ezzatollah; Ghanbari, Reza Namdar

    2013-03-01

    Kaftar Lake is a high-altitude fresh water lake located in High Zagros, south of Iran. Despite the high annual evaporation to precipitation ratio in the area, lake water electrical conductivity is usually lower than 1000 µS/cm, this may be due to high seepage from the floor of the lake. Therefore, the hypothesis of possible underground connections between Namdan Basin, where the lake is located, and the surrounding basins with lower elevation (Aspas and Dehbid Basins) was investigated. Hydrogeology, hydrochemistry, and stable isotopes data of the lake and surrounding basins along with the lake water balance study were applied to test the hypothesis. Results indicate that Kaftar Lake has no connection with Aspas Basin in south, but it is hydraulically connected to Dehbid Basin. In Dehbid Basin, "Ghasr_e_Yaghoob spring" (average discharge ≅1200 L/s) emerges from a small outcrop (about 0.8 km(2) ) of Daryan limestone Formation, where this outcrop is much smaller than the required recharge area for such average discharge rate. The study shows that this spring is recharged by Kaftar Lake and Namdan Basin aquifer, through Daryan Formation of Gandboee Syncline located to the northern part of the lake. © 2012, The Author(s). Groundwater © 2012, National Ground Water Association.

  9. Comment on "The deglaciation over the Laurentide Fan: History of diatoms, IRD, ice and fresh water"

    NASA Astrophysics Data System (ADS)

    Carlson, Anders E.; Clark, Peter U.; Leydet, David J.; Rayburn, John A.

    2016-05-01

    Gil et al. (2015) present new and existing data in core OCE326 GGC14 from the Laurentian Fan off of the Laurentian Channel. In their study, they criticize data published from the same core by Obbink et al. (2010) and from a nearby core by Carlson et al. (2007). One major conclusion of Gil et al. (2015) is that "The YD [Younger Dryas cold event; 12.9-11.7 ka; Rasmussen et al., 2006] cannot be regarded as an event triggered by a fresh water input through the Laurentian Channel since only a weak brief input nearly 1000 yrs after its onset is recorded." Here we show that their study misrepresents existing data, and ignores their own data and its uncertainty, which leads to different conclusions than in Gil et al. (2015).

  10. Molecular identification of the occurrence of magnetotactic bacteria in fresh water sediments (Czech Republic)

    PubMed Central

    Rulík, Martin; Chaudhary, Prem Prashant

    2014-01-01

    Magnetotactic bacteria (MTB) are of considerable interest because of their importance in the manufacture of various bioinspired materials. In order to find out the status of magnetotactic bacteria at three different sediment in Czech Republic, samples collected from both standing and running freshwaters were subjected to molecular diversity analysis by using 16S rRNA gene approach. Total community DNA from sediment sample was isolated and used for PCR, cloning and sequence analysis. Of the 24 analyzed sequences, six clones are closely related to Magnetobacterium sp. affiliated with the Nitrospira phylum which showed the dominance of Magnetobacterium phylotypes in the sample. This study will provide useful insight about the community structure of MTB in this particular geographical region. However more detailed and specific studies are warranted in order to properly assess the community structure of MTB’s in fresh water sediments. PMID:25763029

  11. Energetics of Anaerobic Sodium Transport by the Fresh Water Turtle Bladder

    PubMed Central

    Klahr, Saulo; Bricker, Neal S.

    1965-01-01

    Certain of the metabolic events associated with anaerobic sodium transport by the isolated bladder of the fresh water turtle have been investigated. The data suggest that energy for this transport arises from glycolysis and that endogenous glycogen was the major and perhaps the sole source of substrate. The rate of anaerobic glycolysis, as determined by lactate formation, correlates well with the rate as determined by glycogen utilization. Using lactate formation as the index of anaerobic glycolysis, a linear relationship was observed between glycolysis and net anaerobic sodium transport. In the absence of sodium transport, glycolysis decreased by approximately 45 per cent. Tissue ATP concentrations were maintained at about the same level under anaerobic as under aerobic conditions. Finally if it is assumed that in the conversion of glycogen to lactate anaerobically, 3 moles of ATP are generated per mole of glucose residue, an average of over 15 equivalents of sodium were transported for every mole of ATP generated. PMID:14324976

  12. Molecular identification of the occurrence of magnetotactic bacteria in fresh water sediments (Czech Republic).

    PubMed

    Rulík, Martin; Chaudhary, Prem Prashant

    2014-01-01

    Magnetotactic bacteria (MTB) are of considerable interest because of their importance in the manufacture of various bioinspired materials. In order to find out the status of magnetotactic bacteria at three different sediment in Czech Republic, samples collected from both standing and running freshwaters were subjected to molecular diversity analysis by using 16S rRNA gene approach. Total community DNA from sediment sample was isolated and used for PCR, cloning and sequence analysis. Of the 24 analyzed sequences, six clones are closely related to Magnetobacterium sp. affiliated with the Nitrospira phylum which showed the dominance of Magnetobacterium phylotypes in the sample. This study will provide useful insight about the community structure of MTB in this particular geographical region. However more detailed and specific studies are warranted in order to properly assess the community structure of MTB's in fresh water sediments.

  13. Susceptibility of Iraqi fresh water snails to infection with Schistosoma haematobium and Schistosoma mansoni Egyptian strains.

    PubMed

    Wajdi, N A; Hussain, W I; El-Hawary, M F

    1979-01-01

    A great number of Egyptian workers and farmers are seeking settlement in Iraq and some of them proved to have either Schistosoma Haematobium (S.h.) or Schistosoma mansoni (S.m) or even mixed infection. Besides, there is the possibility that some of the Iraqi fresh water snails may prove to be susceptible to infection by one or both of the Schistosoma Egyptian strains. The present study deals with investigations on the susceptibility of Iraqi B. truncatus, Gyranaulus ehrenbergi, Physa c.f. fontinalis, Lymnea lagetis, Melanoides tuberculata and Melanopsis nodes by these parasites. Egyptian S. haematobium but not Egyptian S. mansoni infect Iraqi B. truncatus and both proved to be unable to infect any of the other snails included in the study. Yet, the number of cercariae shedded by B. truncatus snails infected with the Egyptian S. haematobium strain, was much less that the number of cercariae shedded by these snails when infected with the Iraqi S. Haematobium strain.

  14. [Biogeographic zonation of the Eurasian fresh waters based on the macrobenthic faunas].

    PubMed

    Chertoprud, M V

    2010-01-01

    Spatial differentiation of the Eurasian freshwater faunas is analyzed based on the original and published data on the aquatic insects, crustaceans, and mollusks (about 8800 species in total). The Hacker-Dice similarity index is employed as a principal criterion of differentiation. The schemes of biogeographic zonation are constructed for the nine large macrobenthic taxa, namely, Odonata, Ephemeroptera, Plecoptera, Hemiptera, Coleoptera, Trichoptera, Malacostraca, Gastropoda, and Bivalvia. Discussed are principal discordances in distribution of three different ecological-systematic groups of the macrobenthos, namely, limnophylic insects, rheophylic insects, and crustaceans with mollusks. A generalized zonation system of the Eurasian fresh waters is elaborated, which is fundamentally divided into Palaearctic and Oriental Regions. The former is further divided into five subregions: Euro-Ob, Near East, Central Asia, Eastern Siberia, and Japan. The latter is divided into three subregions: Indo-Himalaya, China, and Malay. Preliminary classification of the provinces is also provided. Disagreements between the biogeographic systems of different authors are discussed.

  15. Applicability of ERTS to Antarctic iceberg resources. [harvesting sea ice for fresh water

    NASA Technical Reports Server (NTRS)

    Hult, J. L. (Principal Investigator); Ostrander, N. C.

    1973-01-01

    The author has identified the following significant results. This investigation explorers the applicability of ERTS to (1) determine the Antarctic sea ice and environmental behavior that may influence the harvesting of icebergs, and (2) monitor iceberg locations, characteristics, and evolution. Imagery has shown that the potential applicability of ERTS to the research, planning, and harvesting operations can contribute importantly to the glowing promise derived from broader scope studies for the use of Antarctic icebergs to relieve a growing global thirst for fresh water. Several years of comprehensive monitoring will be necessary to characterize sea ice and environmental behavior and iceberg evolution. Live ERTS services will assist harvesting control and claiming operations and offer a means of harmonizing entitlements of iceberg resources. The valuable ERTS services will be more cost effective than other means will be easily justified and borne by the iceberg harvesting operations.

  16. Isolation, purification and identification of etiolation substrate from fresh-cut Chinese water-chestnut (Eleocharis tuberosa).

    PubMed

    Pan, Yong-Gui; Li, Yi-Xiao; Yuan, Meng-Qi

    2015-11-01

    Fresh cut Chinese water-chestnut is a popular ready-to-eat fresh-cut fruit in China. However, it is prone to etiolation and the chemicals responsible for this process are not known yet. To address this problem, we extracted phytochemicals from etiolated Chinese water-chestnut and separated them using MPLC and column chromatography. Four compounds were obtained and their structures were determined by interpretation of UV, TLC, HPLC and NMR spectral data and by comparison with reported data. We identified these compounds as eriodictyol, naringenin, sucrose and ethyl D-glucoside. Among those, eriodictyol and naringenin were both isolated for the first time in fresh-cut Chinese water-chestnut and are responsible for the yellowing of this fruit cutting.

  17. [Identification of organic solvents in the water of a freshly coated drinking-water reservoir].

    PubMed

    Karrenbrock, F; Haberer, K

    1982-01-01

    Chloro-caoutschouc coatings on reservoirs made of concrete can release organic solvents to the drinking water for several month after applying. These solvents can be identified directly in the water by highly sensitive analytical methods (GC/MS). The concentrations verified distinctly exceed the maximum permissible concentration of 10 micrograms/l as suggested by the EEG for the parameter: "dissolved or emulsified hydrocarbons (after extraction by petroleum ether); mineral oils" (2). Protective chloro-caoutchouc coatings should therefore be tested for the release of organic substances to water according to the KTW-Recommendations of the German Federal Health Bureau (1). In future drinking water reservoirs should not be coated unless compelling reasons exist, such as to protect concrete against aggressive water.

  18. Microbial and chemical characterization of underwater fresh water springs in the Dead Sea.

    PubMed

    Ionescu, Danny; Siebert, Christian; Polerecky, Lubos; Munwes, Yaniv Y; Lott, Christian; Häusler, Stefan; Bižić-Ionescu, Mina; Quast, Christian; Peplies, Jörg; Glöckner, Frank Oliver; Ramette, Alban; Rödiger, Tino; Dittmar, Thorsten; Oren, Aharon; Geyer, Stefan; Stärk, Hans-Joachim; Sauter, Martin; Licha, Tobias; Laronne, Jonathan B; de Beer, Dirk

    2012-01-01

    Due to its extreme salinity and high Mg concentration the Dead Sea is characterized by a very low density of cells most of which are Archaea. We discovered several underwater fresh to brackish water springs in the Dead Sea harboring dense microbial communities. We provide the first characterization of these communities, discuss their possible origin, hydrochemical environment, energetic resources and the putative biogeochemical pathways they are mediating. Pyrosequencing of the 16S rRNA gene and community fingerprinting methods showed that the spring community originates from the Dead Sea sediments and not from the aquifer. Furthermore, it suggested that there is a dense Archaeal community in the shoreline pore water of the lake. Sequences of bacterial sulfate reducers, nitrifiers iron oxidizers and iron reducers were identified as well. Analysis of white and green biofilms suggested that sulfide oxidation through chemolitotrophy and phototrophy is highly significant. Hyperspectral analysis showed a tight association between abundant green sulfur bacteria and cyanobacteria in the green biofilms. Together, our findings show that the Dead Sea floor harbors diverse microbial communities, part of which is not known from other hypersaline environments. Analysis of the water's chemistry shows evidence of microbial activity along the path and suggests that the springs supply nitrogen, phosphorus and organic matter to the microbial communities in the Dead Sea. The underwater springs are a newly recognized water source for the Dead Sea. Their input of microorganisms and nutrients needs to be considered in the assessment of possible impact of dilution events of the lake surface waters, such as those that will occur in the future due to the intended establishment of the Red Sea-Dead Sea water conduit.

  19. An Italian study on Cryptosporidium and Giardia in wastewater, fresh water and treated water.

    PubMed

    Briancesco, Rossella; Bonadonna, Lucia

    2005-05-01

    Cryptosporidium oocysts and Giardia cysts has been isolated from waters worldwide. In Italy, studies on these parasites in the environment are still limited due to absence of epidemiological evidence and difficulty of adequate methodologies of sampling and analysis. The new Drinking Water Directive 98/83/CE states that Cryptosporidium has to be determined in water intended for human consumption if Clostridium perfringens is detected. This investigation contributes to the knowledge of both Cryptosporidium and Giardia occurrences in Italian aquatic environments through a two-year monitoring program. In addition, indicator bacteria and Clostridium perfringens were monitored in sewage, surface waters, drinking water, and swimming pools and possible correlations were calculated among all the selected parameters. Cysts and oocysts were detected in sewage and surface water and Giardia numbers always prevailed over Cryptosporidium. The parasites were not detected in drinking water, while a positive sample was obtained from the analysis of swimming pools. Pearson's correlation coefficients evidenced a reciprocal correlation between both the protozoa and the Enterococci counts.

  20. Experimental evaluation of four infiltration models for calcareous soil irrigated with treated untreated grey water and fresh water

    NASA Astrophysics Data System (ADS)

    Gharaibeh, M. A.; Eltaif, N. I.; Alrababah, M. A.; Alhamad, M. N.

    2009-04-01

    Infiltration is vital for both irrigated and rainfed agriculture. The knowledge of infiltration characteristics of a soil is the basic information required for designing an efficient irrigation system. The objective of the present study was to model soil infiltration using four models: Green and Ampt, Horton, Kostaikov and modified Kostiakov. Infiltration tests were conducted on field plot irrigated with treated, untreated greywater and fresh water. The field water infiltration data used in these models were based on double ring infiltrometer tests conducted for 4 h. The algebraic parameters of the infiltration models and nonlinear least squares regression were fitted using measured infiltration time [I (t)] data. Among process-based infiltration models, the Horton model performed best and matched the measured I (t) data with lower sum of squares (SS).

  1. Effects of wattle extract on Microcystic aeruginosa growth and the simulated mini fresh water ecosystem.

    PubMed

    Lirong, Zhou; Linglong, Hou; Yunyan, Hu; Jingguo, Song; Wenqing, Chen

    2010-11-01

    In recent years, there has been an apparent increase in the occurrence of harmful algalblooms in fresh waters. The value of applying the novel wattle extract (Acacia mimosa) to inhibitalgal growth was assessed. Our results showed that the growth of Microcystis aeruginosa was successfully repressed by the plant extract and resulted in decreased extracellular microcystin-LR production. In the experiments, it showed a very effective inhibition in the stage of exponential growth (the largest decrease in level is 47.3% of the control) especially in nonsterile conditions, and the extract can reduce 14.5-24.7% cell density of the control in the stationary stage. In outdoor experiments, the extract reduced dissolved oxygen and pH, and selectively cut down cyanobacterial cell density to one-third of the control after 36 d of treatment. Accordingly due to competitive inhibition in interspecies, other nanoalgae and small-sized aquatic animals declined, while macrozooplankton increased. Finally more large algae were eliminated and thereby the water treated was clarified and the recovery of the freshwater ecosystem was promoted. Hence, the present study suggested a new and more effective and very low ecological risk approach to reduce nuisance blooms cyanobacteria in eutrophic water

  2. Determination of (99)Tc in fresh water using TRU resin by ICP-MS.

    PubMed

    Guérin, Nicolas; Riopel, Remi; Kramer-Tremblay, Sheila; de Silva, Nimal; Cornett, Jack; Dai, Xiongxin

    2017-10-02

    Technetium-99 ((99)Tc) determination at trace level by inductively coupled plasma mass spectrometry (ICP-MS) is challenging because there is no readily available appropriate Tc isotopic tracer. A new method using Re as a recovery tracer to determine (99)Tc in fresh water samples, which does not require any evaporation step, was developed. Tc(VII) and Re(VII) were pre-concentrated on a small anion exchange resin (AER) cartridge from one litre of water sample. They were then efficiently eluted from the AER using a potassium permanganate (KMnO4) solution. After the reduction of KMnO4 in 2 M sulfuric acid solution, the sample was passed through a small TRU resin cartridge. Tc(VII) and Re(VII) retained on the TRU resin were eluted using near boiling water, which can be directly used for the ICP-MS measurement. The results for method optimisation, validation and application were reported. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  3. High resolution Raman lidar measurements for the characterization of the water vapour inflow in the frame of the Hydrological Cycle in the Mediterranean Experiment

    NASA Astrophysics Data System (ADS)

    Di Girolamo, Paolo; Cacciani, Marco; Stelitano, Dario; Summa, Donato

    2013-04-01

    The University of BASILicata Raman Lidar system (BASIL) was deployed in Candillargues (Southern France, Lat: 43°37' N, Long: 4° 4' E) in the frame of the Hydrological Cycle in the Mediterranean Experiment - HyMeX. Within this experiment a major field campaign (Special Observation Period 1-SOP1, September to November 2012) took place over the Northwestern Mediterranean Sea and its surrounding coastal regions in France, Italy and Spain, with a specific focus on the study of heavy precipitation and flash-flood events. During HyMeX-SOP1, BASIL operated between 5 September and 5 November 2012, collecting more than 600 hours of measurements, distributed over 51 measurement days and 19 intensive observation periods (IOPs). The major feature of BASIL is represented by its capability to perform high-resolution and accurate measurements of atmospheric temperature and water vapour, both in daytime and night-time, based on the application of the rotational and vibrational Raman lidar techniques in the UV (Di Girolamo et al., 2004, 2006, 2009). This makes it an ideal tool for the characterization of the water vapour inflow in Southern France, which is important piece of information to improve the comprehension and forecasting capabilities of heavy precipitations in the Northwestern Mediterranean basin. Preliminary measurements from this field deployment will be illustrated and discussed at the Conference. These measurements allow to monitor and characterize the marine atmospheric flow that transport moist and conditionaly unstable air towards the coasts, which is feeding into the HPE events in Southern France. Measurements from BASIL can also be used to better characterize Planetary Boundary Layer moisture transport mechanisms from the surface to deep-convection systems. Besides temperature and water vapour, BASIL also provides measurements of the particle (aerosol/cloud) backscattering coefficient at 355, 532 and 1064 nm, of the particle extinction coefficient at 355 and 532

  4. Contaminant Loading in Drainage and Fresh Water Used for Wetland Management at Stillwater National Wildlife Refuge

    PubMed

    Kilbride; Paveglio; Altstatt; Henry; Janik

    1998-08-01

    Throughout the western United States, studies have identified various detrimental effects of contaminants to aquatic biota from the use of agricultural drainage water for management of arid wetlands. However, little is known about the relative contributions of contaminant loading from pollutants dissolved in water compared with those carried by drifting material (e.g., detritus) associated with drainage water. Consequently, we determined loading rates for contaminants dissolved in water and those incorporated by drifting material for drainage (Diagonal Drain) as well as fresh (S-Line Canal) water used for wetland management at Stillwater National Wildlife Refuge (SNWR), Nevada during the early, middle, and late periods of the irrigation season (June through mid-November) in 1993. We found loading rates for trace elements throughout the irrigation season were almost entirely (> 98%) associated with contaminants dissolved in the water rather than incorporated by drift. Although drift contributed little to the total loading for trace elements to SNWR wetlands, contaminant concentrations were much greater in drift compared with those dissolved in water. Loading rates for dissolved As, B, Hg, and total dissolved solids (TDS) differed among periods for the Diagonal Drain. Along the Diagonal Drain, loading rates for dissolved As, B, Hg, Mo, unionized ammonia (NH3-N), TDS, and Zn differed among its three sampling sites. B was the only trace element with differences in loading rates for drift among periods from the Diagonal Drain. In contrast, loading rates for As, B, Cr, Cu, Hg, Se, and Zn in drift differed among periods for the S-Line Canal. Along Diagonal Drain, loading rates in drift for B (middle and late periods), Cr, Cu, and Zn differed among sites. Hg (x- >/= 12.0 ng/L) and NH3-N (x- >/= 0.985 mg/L) dissolved in water as well as B (x- >/= 97.4 µg/g DW) and Hg (x- >/= 0.461 µg/g DW) in drift from the Diagonal Drain and S-Line Canal exceeded screening levels (SLs

  5. The effect on slurry water as a fresh water replacement in concrete properties

    NASA Astrophysics Data System (ADS)

    Kadir, Aeslina Abdul; Shahidan, Shahiron; Hai Yee, Lau; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    Concrete is the most widely used engineering material in the world and one of the largest water consuming industries. Consequently, the concrete manufacturer, ready mixed concrete plant is increased dramatically due to high demand from urban development project. At the same time, slurry water was generated and leading to environmental problems. Thus, this paper is to investigate the effect of using slurry water on concrete properties in term of mechanical properties. The basic wastewater characterization was investigated according to USEPA (Method 150.1 & 300.0) while the mechanical property of concrete with slurry water was compared according to ASTM C1602 and BS EN 1008 standards. In this research, the compressive strength, modulus of elasticity and tensile strength were studied. The percentage of wastewater replaced in concrete mixing was ranging from 0% up to 50%. In addition, the resulted also suggested that the concrete with 20% replacement of slurry water was achieved the highest compressive strength and modulus of elasticity compared to other percentages. Moreover, the results also recommended that concrete with slurry water mix have better compressive strength compared to control mix concrete.

  6. Ecological impact of a fresh-water ``reef kill'' in Kaneohe Bay, Oahu, Hawaii

    NASA Astrophysics Data System (ADS)

    Jokiel, P. L.; Hunter, C. L.; Taguchi, S.; Watarai, L.

    1993-11-01

    Storm floods on the night of December 31, 1987 reduced salinity to 15‰ in the surface waters of Kaneohe Bay, resulting in massive mortality of coral reef organisms in shallow water. A spectacular phytoplankton bloom occurred in the following weeks. Phytoplankton growth was stimulated by high concentrations of plant nutrients derived partially from dissolved material transported into the bay by flood runoff and partially by decomposition of marine organisms killed by the flood. Within two weeks of the storm, chlorophyll a concentrations reached 40 mg m-3, one of the highest values ever reported. The extremely rapid growth rate of phytoplankton depleted dissolved plant nutrients, leading to a dramatic decline or “crash” of the phytoplankton population. Water quality parameters returned to values approaching the long-term average within 2 to 3 months. Corals, echinoderms, crustaceans and other creatures suffered extremely high rates of mortality in shallow water. Virtually all coral was killed to depths of 1 2m in the western and southern portions of the bay. Elimination of coral species intolerant to lowered salinity during these rare flood events leads to dominance by the coral Porites compressa. After a reef kill, this species can eventually regenerate new colonies from undifferentiated tissues within the “dead” perforate skeleton. Catastrophic flood disturbances in Kaneohe Bay are infrequent, probably occurring once every 20 to 50 years, but play an important role in determination of coral community structure. The last major fresh water reef kill occurred in 1965 when sewage was being discharged into Kaneohe Bay. Coral communities did not recover until after sewage abatement in 1979. Comparison between recovery rate after the two flood events suggests that coral reefs can recover quickly from natural disturbances, but not under polluted conditions.

  7. Microbial and Chemical Characterization of Underwater Fresh Water Springs in the Dead Sea

    PubMed Central

    Ionescu, Danny; Siebert, Christian; Polerecky, Lubos; Munwes, Yaniv Y.; Lott, Christian; Häusler, Stefan; Bižić-Ionescu, Mina; Quast, Christian; Peplies, Jörg; Glöckner, Frank Oliver; Ramette, Alban; Rödiger, Tino; Dittmar, Thorsten; Oren, Aharon; Geyer, Stefan; Stärk, Hans-Joachim; Sauter, Martin; Licha, Tobias; Laronne, Jonathan B.; de Beer, Dirk

    2012-01-01

    Due to its extreme salinity and high Mg concentration the Dead Sea is characterized by a very low density of cells most of which are Archaea. We discovered several underwater fresh to brackish water springs in the Dead Sea harboring dense microbial communities. We provide the first characterization of these communities, discuss their possible origin, hydrochemical environment, energetic resources and the putative biogeochemical pathways they are mediating. Pyrosequencing of the 16S rRNA gene and community fingerprinting methods showed that the spring community originates from the Dead Sea sediments and not from the aquifer. Furthermore, it suggested that there is a dense Archaeal community in the shoreline pore water of the lake. Sequences of bacterial sulfate reducers, nitrifiers iron oxidizers and iron reducers were identified as well. Analysis of white and green biofilms suggested that sulfide oxidation through chemolitotrophy and phototrophy is highly significant. Hyperspectral analysis showed a tight association between abundant green sulfur bacteria and cyanobacteria in the green biofilms. Together, our findings show that the Dead Sea floor harbors diverse microbial communities, part of which is not known from other hypersaline environments. Analysis of the water’s chemistry shows evidence of microbial activity along the path and suggests that the springs supply nitrogen, phosphorus and organic matter to the microbial communities in the Dead Sea. The underwater springs are a newly recognized water source for the Dead Sea. Their input of microorganisms and nutrients needs to be considered in the assessment of possible impact of dilution events of the lake surface waters, such as those that will occur in the future due to the intended establishment of the Red Sea−Dead Sea water conduit. PMID:22679498

  8. Water Follies: Groundwater Pumping and the Fate of America's Fresh Waters

    NASA Astrophysics Data System (ADS)

    Glennon, R.

    2002-12-01

    The next time you open a bottle of spring water, consider that it may have come from a well that is drying up a blue-ribbon trout stream. The next time you super-size a meal at McDonald's, note that the fries are all the same length. That's because the potato farmers irrigate their fields with groundwater from wells, some adjacent to nearby rivers. The next time you purchase gold jewelry, consider that it may have come from a mine that has pumped so much groundwater to de-water the gold-bearing rock that 60 to100 years will pass before the water table recovers. The next time you water your suburban lawn, pause to reflect on what that's doing to the nearby wetland. And the next time you visit Las Vegas and flip on the light in your hotel room, consider that the electricity may have been generated by a coal-fired power plant supplied by a slurry pipeline that uses groundwater critical to springs sacred to the Hopi people. These and countless other seemingly innocuous activities reflect our individual and societal dependence on groundwater that is hydrologically connected to surface water. Hydrologists understand that ground and surface water are interconnected, but frequently the legal rules governing water distinguish between ground and surface water. This has led to groundwater pumping that has dried up many rivers, particularly in the arid West. In Arizona, many once verdant streams have become desiccated sandboxes as city, mines, and farms pumped groundwater to such an extent that surface flows were totally depleted. The problem of the impact of groundwater pumping on the environment, however, is not confined to the arid West. It is an enormous national, indeed international problem. This presentation will focus on the United States and illustrate with examples from around the country the array of environmental problems caused by excessive groundwater pumping. The locations of these case studies range from Maine to California, from Minnesota to Florida, and from

  9. Carbon cycle. Sunlight controls water column processing of carbon in arctic fresh waters.

    PubMed

    Cory, Rose M; Ward, Collin P; Crump, Byron C; Kling, George W

    2014-08-22

    Carbon in thawing permafrost soils may have global impacts on climate change; however, the factors that control its processing and fate are poorly understood. The dominant fate of dissolved organic carbon (DOC) released from soils to inland waters is either complete oxidation to CO2 or partial oxidation and river export to oceans. Although both processes are most often attributed to bacterial respiration, we found that photochemical oxidation exceeds rates of respiration and accounts for 70 to 95% of total DOC processed in the water column of arctic lakes and rivers. At the basin scale, photochemical processing of DOC is about one-third of the total CO2 released from surface waters and is thus an important component of the arctic carbon budget.

  10. Does salt water intrusion constitute a mercury contamination risk for coastal fresh water aquifers?

    PubMed

    Protano, G; Riccobono, F; Sabatini, G

    2000-12-01

    Four different sampling surveys were carried out in 1998 to evaluate the possible causes of severe mercury contamination involving many wells spread over a vast territory along the coast of southern Tuscany (Italy). Several samples of groundwater and coastal sea water were collected to determine the Hg, Cl, Ar, He and N contents. Anthropogenic or deep-seated sources of the Hg involved in the contamination event can be excluded. The observed coupling of Hg pollution with progressive salt water intrusion along the coastal aquifer indicates a close causal relation between these two phenomena.

  11. Compensation for hypercapnia by a euryhaline elasmobranch: effect of salinity and roles of gills and kidneys in fresh water.

    PubMed

    Choe, Keith Patrick; Evans, David H

    2003-05-01

    Specimens of the euryhaline elasmobranch, Dasyatis sabina were acclimated to seawater and fresh water, and exposed to normocapnic (air) and hypercapnic (1% CO2 in air) environmental water. Blood pH, PCO2, and [HCO3-], as well as whole-animal net-acid excretion, were measured for up to 24 h of hypercapnia. In a separate experimental series, urine was collected from freshwater acclimated stingrays during 8 h of normocapnia and hypercapnia. Stingrays in both salinities at least partially compensated for the respiratory acidosis by accumulating HCO3- in their extracellular spaces. The degree of compensation for blood pH was 88.5% in seawater, but only 31.0% in fresh water after 24 h of hypercapnia. Whole-animal net-acid excretion was also greater in seawater than in fresh water, as was the increase in extracellular fluid [HCO3-]. Mean urinary net-acid excretion rates were slightly negative, and never increased above normocapnic control rates during hypercapnia. Since whole-animal net-acid excretion rates increased with blood [HCO3-], and urinary excretion was always negative, the gills were probably the primary organ responsible for compensation from environmental hypercapnia. The faster, and more complete, compensation for hypercapnia in seawater than in fresh water for this euryhaline elasmobranch is consistent with data for euryhaline teleosts, and probably reflects Na+-dependent mechanisms of branchial acid excretion.

  12. Insight into the prevalence and distribution of microbial contamination to evaluate water management in the fresh produce processing industry.

    PubMed

    Holvoet, Kevin; Jacxsens, Liesbeth; Sampers, Imca; Uyttendaele, Mieke

    2012-04-01

    This study provided insight into the degree of microbial contamination in the processing chain of prepacked (bagged) lettuce in two Belgian fresh-cut produce processing companies. The pathogens Salmonella and Listeria monocytogenes were not detected. Total psychrotrophic aerobic bacterial counts (TPACs) in water samples, fresh produce, and environmental samples suggested that the TPAC is not a good indicator of overall quality and best manufacturing practices during production and processing. Because of the high TPACs in the harvested lettuce crops, the process water becomes quickly contaminated, and subsequent TPACs do not change much throughout the production process of a batch. The hygiene indicator Escherichia coli was used to assess the water management practices in these two companies in relation to food safety. Practices such as insufficient cleaning and disinfection of washing baths, irregular refilling of the produce wash baths with water of good microbial quality, and the use of high product/water ratios resulted in a rapid increase in E. coli in the processing water, with potential transfer to the end product (fresh-cut lettuce). The washing step in the production of fresh-cut lettuce was identified as a potential pathway for dispersion of microorganisms and introduction of E. coli to the end product via cross-contamination. An intervention step to reduce microbial contamination is needed, particularly when no sanitizers are used as is the case in some European Union countries. Thus, from a food safety point of view proper water management (and its validation) is a critical point in the fresh-cut produce processing industry.

  13. Determination of low-level Radium isotope activities in fresh waters by gamma spectrometry.

    PubMed

    Molina Porras, Arnold; Condomines, Michel; Seidel, Jean Luc

    2017-02-01

    A new portable sampling system was developed to extract Radium isotopes from large volumes (up to 300L) of fresh surface- and ground-waters of low Ra-activities (<5mBq/L). Ra is quantitatively adsorbed on a small amount (6.5g) of MnO2-coated acrylic fibers, which are then dried and burned at 600°C in the laboratory. The resulting Mn-oxide powder (about 2cm(3) when compacted) is then analyzed through gamma-ray spectrometry which allows measurement of the whole Ra quartet ((226)Ra, (228)Ra, (224)Ra and (223)Ra) in a single counting of a few days. The usual relative standard combined uncertainties (1σ) are 2-3% for (226)Ra, (228)Ra and (224)Ra; and less than 10% for (223)Ra. This method was applied to the analysis of Ra in karstic waters of the Lez aquifer, and surface- and ground-waters of the upper and middle Vidourle watershed (South of France). The analyzed waters have relatively low (226)Ra activities (1-4mBq/L) in both cases, regardless of the contrasted geology (Mesozoic limestone vs crystalline Variscan basement), but clearly distinct ((228)Ra/(226)Ra) ratios in agreement with the differences in Th/U ratios of the two drained areas. Short-lived Ra isotopes ((224)Ra and (223)Ra) appear to be mainly influenced by near-surface desorption/recoil processes for most of the sampling sites. Copyright © 2016. Published by Elsevier Ltd.

  14. Toxic effects of the herbicide Roundup in the guppy Poecilia vivipara acclimated to fresh water.

    PubMed

    Harayashiki, Cyntia Ayumi Yokota; Varela, Antonio Sergio; Machado, Anderson Abel de Souza; Cabrera, Liziara da Costa; Primel, Ednei Gilberto; Bianchini, Adalto; Corcini, Carine Dahl

    2013-10-15

    Although it is believed that glyphosate-based herbicides are relatively nontoxic to humans, its broad use in agriculture and consequent contamination of aquatic systems is a concern. In the present study, reproductive (sperm quality) and biochemical parameters (acetylcholinesterase and glutathione S-transferase activity, lipoperoxidation, and antioxidant capacity against peroxyl radicals) were evaluated in adult guppies (Poecilia vivipara) acclimated to fresh water and exposed (96 h) to environmentally realistic concentrations of glyphosate (130 and 700 μg L(-1)) as the commercial formulation Roundup. Male guppies exposed to Roundup showed a poorer sperm quality, measured as reduced plasmatic membrane integrity, mitochondrial functionality, DNA integrity, motility, motility period and concentration of spermatic cells, than those kept under control condition (no Roundup addition to the water). Most of the spermatic parameters analyzed showed strong association to each other, which may help to understand the mechanisms underlying the observed reduction in sperm quality. Exposure to Roundup did not alter the biochemical parameters analyzed, though differences between genders were observed and deserve further investigations. Findings from the present study suggest that exposure to environmentally relevant concentrations of Roundup may negatively affect at long-term the reproduction of P. vivipara, with consequent changes in fish populations inhabiting environments contaminated with the herbicide.

  15. Adsorption and desorption kinetics of (60)Co and (137)Cs in fresh water rivers.

    PubMed

    Fiengo Pérez, Fabricio; Sweeck, Lieve; Bauwens, Willy; Van Hees, May; Elskens, Marc

    2015-11-01

    Radionuclides released in water systems--as well as heavy metals and organic toxicants--sorb to both the suspended solid particles and the bed sediments. Sorption is usually represented mathematically by the distribution coefficient. This approach implies equilibrium between phases and instantaneous fixation (release) of the pollutant onto (from) the surface of the soil particle. However, empirical evidence suggests that for some radionuclides the fixation is not achieved instantaneously and that the reversibility of the process can be slow. Here the adsorption/desorption kinetics of (60)Co and (137)Cs in fresh water environments were simulated experimentally and later on modelled mathematically, while the influence of the most relevant factors affecting the sorption were taken into account. The experimental results suggest that for adsorption and the desorption more than 24 h are needed to reach equilibrium, moreover, It was observed that the desorption rate constants for (60)Co and (137)Cs lie within ranges which are of two to three orders of magnitude lower than the adsorption rate constants.

  16. Chemical characterization of high molecular weight dissolved organic matter in fresh and marine waters

    NASA Astrophysics Data System (ADS)

    Repeta, Daniel J.; Quan, Tracy M.; Aluwihare, Lihini I.; Accardi, AmyMarie

    2002-03-01

    The high molecular weight fraction of dissolved organic matter in a suite of lakes, rivers, seawater, and marine sediment interstitial water samples was collected by ultrafiltration and characterized by molecular level and spectroscopic techniques. Proton nuclear magnetic resonance spectra of all samples show a high degree of similarity, with major contributions from carbohydrates, bound acetate, and lipids. Molecular level analyses of neutral sugars show seven monosaccharides, rhamnose, fucose, arabinose, xylose, mannose, glucose, and galactose, to be abundant, and to occur in comparable relative amounts in each sample. Previous studies have emphasized the distinctive composition of dissolved humic substances in fresh and marine waters, and have attributed these differences to sources and transformations of organic matter unique to each environment. In contrast we find a large fraction of freshwater high molecular weight dissolved organic matter (HMWDOM; > 1kD) to be indistinguishable from marine HMWDOM in bulk and molecular-level chemical properties. Aquatic HMWDOM is similar in chemical composition to biologically derived acylated heteropolysaccharides isolated from marine algal cultures, suggesting a biological source for some fraction of persistent HMWDOM. High molecular weight DOC contributes 51 ± 26% of the total DOC, and monosaccharides 18 ± 8% of the total HMWDOC in our freshwater samples. These contributions are on average higher and more variable, but not significantly different than for surface seawater (30% and 16% respectively). Biogeochemical processes that produce, accumulate, and recycle DOM may therefore share important similarities and be broadly comparable across a range of environmental settings.

  17. Risk assessment of cryptosporidium and giardia in water irrigating fresh produce in Mexico.

    PubMed

    Mota, Alain; Mena, Kristina D; Soto-Beltran, Marcela; Tarwater, Patrick M; Cháidez, Cristóbal

    2009-10-01

    A rise in foodborne outbreaks in the United States associated with fresh produce has resulted in increased concerns with the importation of fruits and vegetables. Mexico is a major exporter of produce to the United States, particularly tomatoes and bell peppers. A quantitative microbial risk assessment (QMRA) was conducted to evaluate the public health impact of protozoan-laden water irrigating produce in Culiacan, Sinaloa, Mexico. Specifically, a QMRA was conducted to address the human health impact associated with consumption of tomatoes, bell peppers, cucumbers, and lettuce irrigated with water contaminated with Cryptosporidium and Giardia. Yearly infection risks were estimated and assumed a 120-day exposure in a given year. Annual risks range from 9 x 10(-6) for Cryptosporidium at the lowest concentration associated with bell peppers to almost 2 x 10(-1) for exposure to Giardia on lettuce at the highest detected concentration. With the relatively high number of illnesses resulting from produce-related outbreaks, addressing pre- and postharvest points of contamination for fruits and vegetables consumed raw should be a food industry priority. This research shows how QMRA can be used to interpret microbial contamination data for public health significance and subsequently provide the foundation for guideline development.

  18. Water-table contours, directions of ground-water movement, and measurements of inflow to American Falls Reservoir, Southeastern Idaho, April 1984

    USGS Publications Warehouse

    Young, H.W.

    1984-01-01

    In 1978 the U.S. Geological Survey began a 5-year study of the High Plains regional aquifer system to provide hydrologic information for evaluating the effects of long-term development of the aquifer and to develop a capability for predicting aquifer response to alternative changes in ground-water management. By use of a digital model, this report presents a quantitative description of the High Plains aquifer in Oklahoma. The High Plains aquifer consists predominantly of the Tertiary Ogallala Formation and overlying Quaternary alluvium and terrace deposits which are hydraulically connected to the High Plains aquifer. Much of the aquifer is underlain by formations of Permian through Cretaceous age, which generally have very small hydraulic conductivities. In some areas parts of underlying Triassic, Jurassic, or Cretaceous rocks are hydraulically connected with the aquifer. The High Plains aquifer is a water-table aquifer in which water moves generally to the east-southeast. Before the beginning of extensive irrigation of the 1960's, the aquifer was essentially in dynamic equilibrium with recharge from precipitation balanced by natural discharge from the aquifer. Ground-water discharge appeared in streams leaving the area or was returned to the atmosphere through evapotranspiration. Accurate records of irrigation pumpage are not available from the High Plains. In order to estimate irrigation pumpage, published records of crop distribution were used and a consumptive use was assigned to each principal irrigated crop. This method gave an estimated irrigation demand. Pumpage was taken as a percentage of the total irrigation demand. Irrigation has decreased ground-water discharge from the High Plains aquifer. Ground-water discharge was estimated as approximately 118 cubic feet per second in 1980. A finite-difference digital model was used to simulate flow in the High Plains aquifer. The recharge was adjusted so that 1980 ground-water discharge was 118 cubic feet per

  19. Phosphorus dynamics in soils irrigated with reclaimed waste water or fresh water - A study using oxygen isotopic composition of phosphate

    USGS Publications Warehouse

    Zohar, I.; Shaviv, A.; Young, M.; Kendall, C.; Silva, S.; Paytan, A.

    2010-01-01

    Transformations of phosphate (Pi) in different soil fractions were tracked using the stable isotopic composition of oxygen in phosphate (??18Op) and Pi concentrations. Clay soil from Israel was treated with either reclaimed waste water (secondary, low grade) or with fresh water amended with a chemical fertilizer of a known isotopic signature. Changes of ??18Op and Pi within different soil fractions, during a month of incubation, elucidate biogeochemical processes in the soil, revealing the biological and the chemical transformation impacting the various P pools. P in the soil solution is affected primarily by enzymatic activity that yields isotopic equilibrium with the water molecules in the soil solution. The dissolved P interacts rapidly with the loosely bound P (extracted by bicarbonate). The oxides and mineral P fractions (extracted by NaOH and HCl, respectively), which are considered as relatively stable pools of P, also exhibited isotopic alterations in the first two weeks after P application, likely related to the activity of microbial populations associated with soil surfaces. Specifically, isotopic depletion which could result from organic P mineralization was followed by isotopic enrichment which could result from preferential biological uptake of depleted P from the mineralized pool. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with reclaimed waste water compared to the fertilizer treated soil. ?? 2010 Elsevier B.V.

  20. Fresh water production from municipal waste water with RO membrane technology and its application for agriculture and industry in arid area

    NASA Astrophysics Data System (ADS)

    Yokoyama, F.

    2015-04-01

    One of the biggest problems of the 21st century is the global water shortage. Therefore it is difficult to increase the quantity of conventional water resources such as surface water and groundwater for agriculture and industry in arid area. Technical advancement in water treatment membrane technology including RO membrane has been remarkable especially in recent years. As the pore size of RO membrane is less than one nanometer, it is possible to produce the fresh water, which satisfies the drinking water quality standards, with utilizing RO membrane. In this report a new fresh water resource from municipal waste water is studied to apply to the plant factory which is the water saving type agriculture and industry in arid area.

  1. Comparative analysis of a CFo ATP synthase subunit II homologue derived from marine and fresh-water algae.

    PubMed

    Suda, Yoshito; Yoshikawa, Tomoaki; Okuda, Yuko; Tsunemoto, Mei; Matsuda, Yuri; Tanaka, Satoshi; Ikeda, Kazunori; Miyasaka, Hitoshi; Harada, Kazuo; Bamba, Takeshi; Hirata, Kazumasa

    2009-11-01

    Comparative analysis was performed with a CFo ATP synthase subunit II homologue (CFo-II) derived from marine or fresh-water algae. The marine algae-derived CFo-II-transformed Escherichia coli grew and accumulated ATP more vigorously in NaCl or Cadmium containing medium, suggesting that this gene was useful for the development of stress-tolerant plant.

  2. Discovery of a Balkan fresh-water fauna in the Idaho formation of Snake River Valley, Idaho

    USGS Publications Warehouse

    Dall, W.H.

    1925-01-01

    In 1866 Gabb described Melania taylori and Lithasia antiqua "from a fresh-water deposit on Snake River, Idaho Territory, on the road from Fort Boise to the Owyhee mining country. Collected by A. Taylor." He states that a small bivalve, perhaps a Sphaerium, was associated with them.

  3. Application of Artificial Neuro-Fuzzy Logic Inference System for Predicting the Microbiological Pollution in Fresh Water

    NASA Astrophysics Data System (ADS)

    Bouharati, S.; Benmahammed, K.; Harzallah, D.; El-Assaf, Y. M.

    The classical methods for detecting the micro biological pollution in water are based on the detection of the coliform bacteria which indicators of contamination. But to check each water supply for these contaminants would be a time-consuming job and a qualify operators. In this study, we propose a novel intelligent system which provides a detection of microbiological pollution in fresh water. The proposed system is a hierarchical integration of an Artificial Neuro-Fuzzy Inference System (ANFIS). This method is based on the variations of the physical and chemical parameters occurred during bacteria growth. The instantaneous result obtained by the measurements of the variations of the physical and chemical parameters occurred during bacteria growth-temperature, pH, electrical potential and electrical conductivity of many varieties of water (surface water, well water, drinking water and used water) on the number Escherichia coli in water. The instantaneous result obtained by measurements of the inputs parameters of water from sensors.

  4. Interspecific Aggressive Behaviour of Invasive Pumpkinseed Lepomis gibbosus in Iberian Fresh Waters

    PubMed Central

    Almeida, David; Merino-Aguirre, Raquel; Vilizzi, Lorenzo; Copp, Gordon H.

    2014-01-01

    Pumpkinseed Lepomis gibbosus (L.) are successful invaders in Europe, where this species exerts multiple ecological effects, mainly through trophic interactions. Behavioural interference represents a potential impact for native fauna and this is of particular conservation concern in the Iberian Peninsula because of the highly valuable endemic fauna inhabiting streams of this region. However, aggressive interactions have not previously been examined under natural conditions in Iberian fresh waters. To address this gap in knowledge, the aim of the present study was to assess the effect of pumpkinseed aggression on endemic fauna of an Iberian stream, the River Bullaque (central Spain). In September 2009, we analysed the aggression and environmental contexts of these behavioural interactions by snorkelling: aggressor size, aggression type, shoal size, previous activity to aggression, recipient species, response to aggression, microhabitat structure and prey availability. Small pumpkinseed displayed more threat and fewer pursuit behaviours relative to medium and large individuals, reflecting an ontogenetic behavioural shift from low to high aggression intensity. Small aggressors came from large shoals, with bottom feeding being the most frequently observed activity prior to an aggressive interaction; whereas large pumpkinseed were less gregarious and they were mostly ambulating within the water column prior to aggression. Recipient species of aggression included non-native crayfish and fishes, and more importantly, endemic fishes and frogs. Retreat was the most common response to aggression, irrespective of aggressor size. Small pumpkinseed displayed aggressive behaviours over coarse substrata containing elevated macrobenthos biomass; whereas aggression by large individuals was observed in deeper waters. These findings suggest that small and large pumpkinseed exert a high impact on other stream residents through aggression in competition for food and territory defence

  5. Interspecific aggressive behaviour of invasive pumpkinseed Lepomis gibbosus in Iberian fresh waters.

    PubMed

    Almeida, David; Merino-Aguirre, Raquel; Vilizzi, Lorenzo; Copp, Gordon H

    2014-01-01

    Pumpkinseed Lepomis gibbosus (L.) are successful invaders in Europe, where this species exerts multiple ecological effects, mainly through trophic interactions. Behavioural interference represents a potential impact for native fauna and this is of particular conservation concern in the Iberian Peninsula because of the highly valuable endemic fauna inhabiting streams of this region. However, aggressive interactions have not previously been examined under natural conditions in Iberian fresh waters. To address this gap in knowledge, the aim of the present study was to assess the effect of pumpkinseed aggression on endemic fauna of an Iberian stream, the River Bullaque (central Spain). In September 2009, we analysed the aggression and environmental contexts of these behavioural interactions by snorkelling: aggressor size, aggression type, shoal size, previous activity to aggression, recipient species, response to aggression, microhabitat structure and prey availability. Small pumpkinseed displayed more threat and fewer pursuit behaviours relative to medium and large individuals, reflecting an ontogenetic behavioural shift from low to high aggression intensity. Small aggressors came from large shoals, with bottom feeding being the most frequently observed activity prior to an aggressive interaction; whereas large pumpkinseed were less gregarious and they were mostly ambulating within the water column prior to aggression. Recipient species of aggression included non-native crayfish and fishes, and more importantly, endemic fishes and frogs. Retreat was the most common response to aggression, irrespective of aggressor size. Small pumpkinseed displayed aggressive behaviours over coarse substrata containing elevated macrobenthos biomass; whereas aggression by large individuals was observed in deeper waters. These findings suggest that small and large pumpkinseed exert a high impact on other stream residents through aggression in competition for food and territory defence

  6. Improved method for measuring transparent exopolymer particles (TEP) and their precursors in fresh and saline water.

    PubMed

    Villacorte, Loreen O; Ekowati, Yuli; Calix-Ponce, Helga N; Schippers, Jan C; Amy, Gary L; Kennedy, Maria D

    2015-03-01

    Transparent exopolymer particles (TEP) and their precursors produced by phyto-/bacterio-planktons in fresh and marine aquatic environments are increasingly considered as a major contributor to organic/particulate and biological fouling in micro-/ultra-filtration and reverse osmosis membrane (RO) systems. However, currently established methods which are based on Alcian blue (AB) staining and spectrophotometric techniques do not measure TEP-precursors and have the tendency to overestimate concentration in brackish/saline water samples due to interference of salinity on AB staining. Here we propose a new semi-quantitative method which allows measurement of both TEP and their colloidal precursors without the interference of salinity. TEP and their precursors are first retained on 10 kDa membrane, rinsed with ultra-pure water, and re-suspended in ultra-pure water by sonication and stained with AB, followed by exclusion of TEP-AB precipitates by filtration and absorbance measurement of residual AB. The concentration is then determined based on the reduction of AB absorbance due to reaction with acidic polysaccharides, blank correction and calibration with Xanthan gum standard. The extraction procedure allows concentration of TEP and their pre-cursors which makes it possible to analyse samples with a wide range of concentrations (down to <0.1 mg Xeq/L). This was demonstrated through application of the method for monitoring these compounds in algal cultures and a full-scale RO plant. The monitoring also revealed that concentrations of the colloidal precursors were substantially higher than the concentration of TEP themselves. In the RO plant, complete TEP removal was observed over the pre-treatment processes (coagulation-sedimentation-filtration and ultrafiltration) but the TEP precursors were not completely removed, emphasising the importance of measuring this colloidal component to better understand the role of TEP and acidic polysaccharides in RO membrane fouling.

  7. Nationwide monitoring of mercury in wild and farmed fish from fresh and coastal waters of Korea.

    PubMed

    Kim, Chan-Kook; Lee, Tae-Woo; Lee, Kyu-Tae; Lee, Jong-Hyeon; Lee, Chang-Bok

    2012-11-01

    Mercury (Hg) concentrations were monitored in wild and cultured fish collected from fresh and coastal waters in the Korean peninsula from April 2006 to August 2008 nationwide. Total Hg concentrations were reported for 5043 fish samples, including 78 species from 133 locations. Significant interspecies variation was noted in the Hg levels. The average Hg concentration in each fish species ranged from 6.31 μg kg(-1) for mullet (Mugil cephalus) to 200 μg kg(-1) for mandarin fish (Siniperca scherzeri). Among the species collected, the maximum concentration of Hg, 1720 μg kg(-1), was measured in an Amur catfish (Silurus asotus). Only wild freshwater fish exceeded the WHO ingestion standard. Wild freshwater piscivorous fish samples from a large artificial upstream lake contained the highest Hg levels. Hg concentrations were compared between fish groups categorized as wild and farmed fish from freshwater and coastal waters. Although the wild freshwater fish had similar size ranges, their Hg concentrations were higher than those of the other groups. Compared to the feed of farmed marine and freshwater fishes, the prey of wild freshwater fish had a higher Hg concentration, and the total Hg concentrations in freshwater and associated sediment samples were higher than those in coastal water and associated sediment samples. In the freshwater environment, piscivorous fish bioaccumulated two times more Hg than carnivorous and omnivorous fish and four times more than planktivorous fish. The difference in Hg concentrations among trophic groups might have been due to differences in the size of fish, in addition to the variations among different trophic groups. These data will be useful for developing the fish consumption advisory as a management measure to reduce Hg exposure.

  8. Strains of toxic and harmful microalgae, from waste water, marine, brackish and fresh water.

    PubMed

    Rodríguez-Palacio, M C; Crisóstomo-Vázquez, L; Alvarez-Hernández, S; Lozano-Ramírez, C

    2012-01-01

    Some microalgae are economically important in Mexico and the world because they can be potentially toxic. Algal explosive population growths are named harmful algal blooms and are frequently recorded in Mexico. The authors set up potentially toxic microalgae cultures from the Gulf of Mexico (Garrapatas tideland, Barberena river, Carpintero lagoon in Tamaulipas State; Chalchoapan and Catemaco lakes in Veracruz State), from the Mexican Pacific Ocean, Guerrero, Colima and Michoacán States, and from interior water bodies such as Vicente Aguirre dam, Chapultepec lake and several waste water treatment plants. This research is about the diversity and abundance of phytoplankton in relation a specific site because of harmful algal bloom events. Microalgae cultures are useful in order to solve taxonomic problems, to know life cycles, molecular studies, for the study of toxic species, and the isolation of useful metabolites. The cultures for this research are clonal, non-axenic, semi-continuous, 12:12 light/dark photoperiod, 20 ± 1 °C temperature and 90.5 µmol m(-2)s(-1) illumination. Four different culture media were used. This collection is open to the worldwide scientific community as a source of organisms in controlled conditions that can be used as a useful tool for microalgae research work.

  9. In-Situ Ion Analysis of Fresh Waters via an ISE Multiprobe and Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Mueller, A. V.; Hemond, H.

    2010-12-01

    The ecological and geochemical sciences stand to substantially gain from capability for comprehensive, real-time, in-situ characterization of the chemical constituents of natural waters, e.g. by facilitating rapid high-resolution adaptive sampling campaigns and avoiding the potential errors and high costs related to traditional grab sample collection, transportation and in-lab analysis. In-situ chemical instrumentation also promotes the goals of large-scale monitoring networks, such as CUASHI and WATERS, by reducing the financial and human resources overhead required for traditional sampling at this scale. Problems of environmental remediation and monitoring of industrial waste waters would additionally benefit from such instrumental capacity. We have pursued in-situ measurement of all major ions contributing to the charge makeup (>99%) of oxic natural fresh waters via an instrument combining an array of ion-selective electrode (ISE) hardware with an appropriate multivariate signal processing architecture. Commercially available electrochemical sensors promote low cost and a fast development schedule, as well as easy maintenance and reproduction. Data processing techniques are adapted from artificial intelligence and chemometrics to extract accurate information from the corresponding in-situ data matrix. This architecture takes into account temperature, conductivity, and non-linearity effects, as well as taking advantage of sensor cross-selectivities traditionally considered as interferences. Chemical and mathematical constraints, e.g. charge balance and total ionic strength, provide further system-level information. Maximizing data recovery from the sensor array allows use of the instrument without the standard additions or ionic strength adjustment traditionally-required with use of ISEs. Initial work demonstrates the effectiveness of this methodology at predicting inorganic cations (sodium, potassium, calcium, and ammonium ) and hydrogen ion in a simplified

  10. Infrequent transitions between saline and fresh waters in one of the most abundant microbial lineages (SAR11).

    PubMed

    Logares, Ramiro; Bråte, Jon; Heinrich, Friederike; Shalchian-Tabrizi, Kamran; Bertilsson, Stefan

    2010-02-01

    The aquatic bacterial group SAR11 is one of the most abundant organisms on Earth, with an estimated global population size of 2.4 x 10(28) cells in the oceans. Members of SAR11 have also been detected in brackish and fresh waters, but the evolutionary relationships between the species present in the different environments have been ambiguous. In particular, it was not clear how frequently this lineage has crossed the saline-freshwater boundary during its evolutionary diversification. Due to the huge population size of SAR11 and the potential of microbes for long-distance dispersal, we hypothesized that environmental transitions could have occurred repeatedly during the evolutionary diversification of this group. Here, we have constructed extensive 16S rDNA-based molecular phylogenies and undertaken metagenomic data analyses to assess the frequency of saline-freshwater transitions in SAR11 and to investigate the evolutionary implications of this process. Our analyses indicated that very few saline-freshwater transitions occurred during the evolutionary diversification of SAR11, generating genetically distinct saline and freshwater lineages that do not appear to exchange genes extensively via horizontal gene transfer. In contrast to lineages from saline environments, extant freshwater taxa from diverse, and sometimes distant, geographic locations were very closely related. This points to a rapid diversification and dispersal in fresh waters or to slower evolutionary rates in fresh water SAR11 when compared with marine counterparts. In addition, the colonization of both saline and fresh waters appears to have occurred early in the evolution of SAR11. We conclude that the different biogeochemical conditions that prevail in saline and fresh waters have likely prevented the environmental transitions in SAR11, promoting the evolution of clearly distinct lineages in each environment.

  11. [Water matrices samples: pre-concentration problems and methodologies for ecotoxicological assessment of fresh waters].

    PubMed

    Galassi, Silvana

    2005-01-01

    Biological monitoring and ecotoxicological investigation are research methods for water quality assessment included in the Italian regulation in force (DL.vo 152/99). Biological monitoring must be applied in every case while ecotoxicological investigation is not mandatory. While extended biotic index application methodologies are standardized, pre-concentration sample procedures applied for ecotoxicological investigation are not, because they are applied as research only. Pre-concentration for organic micro-pollutants can be carried out both by means of organic solvents and through SPE (solid phase extraction), being the latter more advantageous than the former. In any case, an intercalibration exercise should be undertaken to assess the applicability of the proposed procedure to all the national territory.

  12. Content of some metals in mean tissue of salt-water and fresh-water fish and in their products.

    PubMed

    Krełowska-Kułas, M

    1995-01-01

    The main goal of this work was to determine the concentration of some metals in meat tissue of salt-water and fresh-water fish and in their products. These studies refer to 13 species of fish most often eaten in Poland, caught in 1992. Fish (samples) for testing and examination were taken from each species once every month during the term of 6 months. The lead content in tested fish and their products did not exceed the set limits (0.6 mg Pb/kg), which were exceeded only in preserve from oyster. The average content of cadmium in flounder, Alaska pollack, Baltic herring, pickled herring pieces and in preserves with shrimp, crab and oyster exceeded the set limits (0.05 mg Cd/kg). The copper and zinc content in tested fish and their products is also within the set domestic limits (10.0 mg Cu/kg and 50.0 mg Zn/kg). The iron (3.6-24.2 mg/kg), magnesium (170-380 mg/kg) and manganese (0.12-0.31 mg/kg) contents in muscle tissue of the tested fish and their products seem to be typical. The presence of absolutely toxic metals (lead and cadmium) in some species of fish and their products points to extreme contamination of water environment by those metals.

  13. Using helicopter TEM to delineate fresh water and salt water zones in the aquifer beneath the Okavango Delta, Botswana

    NASA Astrophysics Data System (ADS)

    Podgorski, Joel E.; Kinzelbach, Wolfgang K. H.; Kgotlhang, Lesego

    2017-09-01

    The Okavango Delta is a vast wetland wilderness in the middle of the Kalahari Desert of Botswana. It is a largely closed hydrological system with most water leaving the delta by evapotranspiration. In spite of this, the channels and swamps of the delta remain surprisingly low in salinity. To help understand the hydrological processes at work, we reanalyzed a previous inversion of data collected from a helicopter transient electromagnetic (HTEM) survey of the entire delta and performed an inversion of a high resolution dataset recorded during the same survey. Our results show widespread infiltration of fresh water to as much as ∼200 m depth into the regional saline aquifer. Beneath the western delta, freshwater infiltration extends to only about 80 m depth. Hydrological modeling with SEAWAT confirms that this may be due to rebound of the regional saltwater-freshwater interface following the cessation of surface flooding over this part of the delta in the 1880s. Our resistivity models also provide evidence for active and inactive saltwater fingers to as much as ∼100 m beneath islands. These results demonstrate the great extent of freshwater infiltration across the delta and also show that all vegetated areas along the delta's channels and swamps are potential locations for transferring solutes from surface water to an aquifer at depth.

  14. Using Snow Fences to Augument Fresh Water Supplies in Shallow Arctic Lakes

    SciTech Connect

    Stuefer, Svetlana

    2013-03-31

    This project was funded by the U.S. Department of Energy, National Energy Technology Laboratory (NETL) to address environmental research questions specifically related to Alaska's oil and gas natural resources development. The focus of this project was on the environmental issues associated with allocation of water resources for construction of ice roads and ice pads. Earlier NETL projects showed that oil and gas exploration activities in the U.S. Arctic require large amounts of water for ice road and ice pad construction. Traditionally, lakes have been the source of freshwater for this purpose. The distinctive hydrological regime of northern lakes, caused by the presence of ice cover and permafrost, exerts influence on lake water availability in winter. Lakes are covered with ice from October to June, and there is often no water recharge of lakes until snowmelt in early June. After snowmelt, water volumes in the lakes decrease throughout the summer, when water loss due to evaporation is considerably greater than water gained from rainfall. This balance switches in August, when air temperature drops, evaporation decreases, and rain (or snow) is more likely to occur. Some of the summer surface storage deficit in the active layer and surface water bodies (lakes, ponds, wetlands) is recharged during this time. However, if the surface storage deficit is not replenished (for example, precipitation in the fall is low and near‐surface soils are dry), lake recharge is directly affected, and water availability for the following winter is reduced. In this study, we used snow fences to augment fresh water supplies in shallow arctic lakes despite unfavorable natural conditions. We implemented snow‐control practices to enhance snowdrift accumulation (greater snow water equivalent), which led to increased meltwater production and an extended melting season that resulted in lake recharge despite low precipitation during the years of the experiment. For three years (2009, 2010

  15. NEURAL RECONNECTION IN THE TRANSECTED SPINAL CORD OF THE FRESH-WATER TURTLE Trachemys dorbignyi

    PubMed Central

    Rehermann, María Inés; Marichal, Nicolás; Russo, Raúl E.; Trujillo-Cenóz, Omar

    2009-01-01

    This paper provides the first evidence that fresh water turtles are able to reconnect their completely transected spinal cord leading to some degree of recovery of the motor functions lost after injury. Videographic analysis showed that some turtles (5 out of 11) surviving more than 20 days after injury were able to initiate stepping locomotion. However the stepping movements were slower than those of normal animals and swimming patterns were not restored. Even though just 45% of the injured turtles recovered their stepping patterns, all showed axonal sprouting beyond the lesion site. Immunocytochemical and electron microscope images revealed the occurrence of regrowing axons crossing the severed region. A major contingent of the axons reconnecting the cord originated from sensory neurons lying in dorsal ganglia adjacent to the lesion site. The axons bridging the damaged region traveled on a cellular scaffold consisting of BLBP and GFAP positive cells and processes. Serotonergic varicose nerve fibers and endings were found at early stages of the healing process at the epicenter of the lesion. Interestingly, the glial scar commonly found in the damaged central nervous system of mammals was absent. In contrast GFAP and BLBP positive processes were found running parallel to the main axis of the cord accompanying the crossing axons. PMID:19418545

  16. Multiwall carbon nanotubes increase the microbial community in crude oil contaminated fresh water sediments.

    PubMed

    Abbasian, Firouz; Lockington, Robin; Palanisami, Thavamani; Megharaj, Mallavarapu; Naidu, Ravi

    2016-01-01

    Since crude oil contamination is one of the biggest environmental concerns, its removal from contaminated sites is of interest for both researchers and industries. In situ bioremediation is a promising technique for decreasing or even eliminating crude oil and hydrocarbon contamination. However, since these compounds are potentially toxic for many microorganisms, high loads of contamination can inhibit the microbial community and therefore reduce the removal rate. Therefore, any strategy with the ability to increase the microbial population in such circumstances can be of promise in improving the remediation process. In this study, multiwall carbon nanotubes were employed to support microbial growth in sediments contaminated with crude oil. Following spiking of fresh water sediments with different concentrations of crude oil alone and in a mixture with carbon nanotubes for 30days, the microbial profiles in these sediments were obtained using FLX-pyrosequencing. Next, the ratios of each member of the microbial population in these sediments were compared with those values in the untreated control sediment. This study showed that combination of crude oil and carbon nanotubes can increase the diversity of the total microbial population. Furthermore, these treatments could increase the ratios of several microorganisms that are known to be effective in the degradation of hydrocarbons. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Structural and optical characterization of fresh water diatoms (Cyclotella sp.): nature's nanoporous silica manufacturing plant

    NASA Astrophysics Data System (ADS)

    Mazumder, Nirmal; Gogoi, Ankur; Buragohain, Alak K.; Ahmed, Gazi A.; Choudhury, Amarjyoti

    2014-02-01

    Siliceous frustules were extracted from a representative fresh water diatom species (Cyclotella sp.) by treating with aqueous hydrochloric (HCl) acid. The structural characterizations of cleaned frustules were examined by scanning electron microscope (SEM). The microscopy images showed that the diatoms have a regular circular shape and are of almost equal size (average length is 9μm and average width is 3 μm). From energy dispersive X -ray spectroscopy (SEM-EDS) spot analysis it was confirmed that the frustules isolated from diatoms are composed mainly of silicon in the form of amorphous silica (SiO2). The bond information of chemical substances of diatom frustules was carried out at ambient temperature by means of Fourier Transform Infrared (FTIR) Spectroscopy. FTIR spectrum as recorded in transmittance mode showed the characteristic peaks for diatom biosilica, including for Si-O-Si stretching vibration at 1057 and 776 cm-1. Photoluminescence (PL) measurements of diatom frustules were performed at room temperature and it was observed that they emitted strong blue PL centered at 440nm when excited with ultraviolet (UV) radiation.

  18. Phytoavailability of heavy metals in tidal flat soils after fresh water leaching.

    PubMed

    Li, QuSheng; Chen, XiaoJiao; Luo, Xuan; Cui, ZhiHong; Shi, Lei; Wang, LiLi; Liu, YaNan

    2012-05-01

    The phytoavailability of Cd, Pb, Cr, Zn, Cu, and Ni, retained in tidal flat soil after fresh water leaching during reclamation was investigated. Two salt-tolerant varieties of tomato (Lycopersicon esculentum) and edible amaranth (Amaranthus mangostanus L.) were planted in soils having eight different desalination levels (from 6.7 to 1.4 g kg(-1) salinity) using pot experiments. Soil leaching significantly decreased the uptake of all metals by crop roots except for Ni. The reduction of soil salinity and exchangeable fraction content of Cd and Pb after leaching contributed to the decrease of uptake of metals by roots. All heavy metal concentrations in the edible parts of both crops in the two lowest salinity level treatments were lower than their maximum allowable levels in food. Results suggest that reclamation of tidal flats can reduce the phytoavailability of the heavy metals retained in soil. But the soil heavy metals may still pose health risks in the cultivation of root food crops. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Effects of nanoplastics and microplastics on toxicity, bioaccumulation, and environmental fate of phenanthrene in fresh water.

    PubMed

    Ma, Yini; Huang, Anna; Cao, Siqi; Sun, Feifei; Wang, Lianhong; Guo, Hongyan; Ji, Rong

    2016-12-01

    Contamination of fine plastic particles (FPs), including micrometer to millimeter plastics (MPs) and nanometer plastics (NPs), in the environment has caught great concerns. FPs are strong adsorbents for hydrophobic toxic pollutants and may affect their fate and toxicity in the environment; however, such information is still rare. We studied joint toxicity of FPs with phenanthrene to Daphnia magna and effects of FPs on the environmental fate and bioaccumulation of (14)C-phenanthrene in fresh water. Within the five sizes particles we tested (from 50 nm to 10 μm), 50-nm NPs showed significant toxicity and physical damage to D. magna. The joint toxicity of 50-nm NPs and phenanthrene to D. magna showed an additive effect. During a 14-days incubation, the presence of NPs significantly enhanced bioaccumulation of phenanthrene-derived residues in daphnid body and inhibited the dissipation and transformation of phenanthrene in the medium, while 10-μm MPs did not show significant effects on the bioaccumulation, dissipation, and transformation of phenanthrene. The differences may be attributed to higher adsorption of phenanthrene on 50-nm NPs than 10-μm MPs. Our findings underlined the high potential ecological risks of FPs, and suggested that NPs should be given more concerns, in terms of their interaction with hydrophobic pollutants in the environment.

  20. Fresh water green microalga Scenedesmus abundans: A potential feedstock for high quality biodiesel production.

    PubMed

    Mandotra, S K; Kumar, Pankaj; Suseela, M R; Ramteke, P W

    2014-03-01

    Present investigation studied the potential of fresh water green microalga Scenedesmus abundans as a feedstock for biodiesel production. To study the biomass and lipid yield, the culture was grown in BBM, Modified CHU-13 and BG-11 medium. Among the tested nitrogen concentration using Modified CHU-13 medium, the highest biomass and lipid yield of 1.113±0.05g/L and 489±23mg/L respectively was found in the culture medium with 0.32g/L of nitrogen (KNO3). Different lipid extraction as well as transesterification methods were also tested. Fatty acid profile of alga grown in large scale indigenous made photobioreactor has shown abundance of fatty acids with carbon chain length of C16 and C18. Various biodiesel properties such as cetane number, iodine value and saponification value were found to be in accordance with Brazilian National Petroleum Agency (ANP255) and European biodiesel standard EN14214 which makes S. abundans as a potential feedstock for biodiesel production.

  1. Emticicia aquatica sp. nov., a species of the family Cytophagaceae isolated from fresh water.

    PubMed

    Joung, Yochan; Seo, Mi-Ae; Kang, Heeyoung; Kim, Haneul; Ahn, Tae-Seok; Cho, Jang-Cheon; Joh, Kiseong

    2015-12-01

    A Gram-staining-negative, non-gliding, orange-pigmented bacterial strain, designated HMF2925T, was isolated from fresh water in Korea. The phylogenetic tree based on 16S rRNA gene sequences showed that strain HMF2925T formed a distinct lineage within the genus Emticicia. Strain HMF2925T was closely related to Emticicia oligotrophica DSM 17448T (95.5 %) and Emticicia ginsengisoli Gsoil 085T (94.1 %). The major fatty acids of strain HMF2925T were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), iso-C15 : 0, C16 : 1ω5c and C16 : 0.The major polar lipids of strain HMF2925T were phosphatidylethanolamine, phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid, two unidentified amino lipids and three unidentified polar lipids. The DNA G+C content of strain HMF2925T was 36.5 mol%. On the basis of the evidence presented in this study, strain HMF2925T represents a novel species of the genus Emticicia, for which the name Emticicia aquatica sp. nov. is proposed. The type strain is HMF2925T ( = KCTC 42574T = CECT 8858T).

  2. Diurnal patterns of the bi-directional reflectance of fresh-water ice

    NASA Technical Reports Server (NTRS)

    Leshkevich, George A.; Deering, Donald W.; Eck, Thomas F.; Ahmad, Suraiya P.

    1990-01-01

    To improve the interpretation of surface cryospheric albedo from satellite sensor data, diurnal measurements of the spectral bidirectional reflectance of a commonly found fresh water ice type were made, from which hemispherical reflectance can be derived. The purpose of this study is to document its clear-sky, bidirectional reflectance characteristics in the visible (650-670 nm) and near-infrared (810-840 nm) region, assess the diurnal nature of the reflectance, and quantify the surface anisotropy. Bidirectional reflectances of the refrozen slush ice measured show a spectral dependence and change significantly with solar zenith angle. Considerable variation occurs at each view angle and among view angles throughout the day. Although diurnal reflectance patterns were similar in both bands, magnitudes varied greatly, being highest in the visible and lowest in the near-infrared region. With the exception of peak saturated (specular) values in the forward scatter direction, bidirectional reflectance was generally highest in the morning when the surface and the illumination were most diffuse in character.

  3. Elimination of free-living amoebae in fresh water with pulsed electric fields.

    PubMed

    Vernhes, M C; Benichou, A; Pernin, P; Cabanes, P A; Teissié, J

    2002-08-01

    This study investigates the effects of pulsed electric fields on the inactivation of trophozoite form of Naegleria lovaniensis Ar9M-1 in batch and flow processes, systematically examining the lethal effect of field strength, pulse duration, number of pulses, and pulse frequency. Our results show that amoebae eradication is modulated by pulse parameters, composition of the pulsing medium, and physiological state of the cells. Cell survival is not related to the energy delivered to the cell suspension during the electrical treatment. For a given energy a strong field applied for a short cumulative pulse duration affects viability more than a weak field with a long cumulative pulsation. We also determine the optimal electrical conditions to obtain an inactivation rate higher than 95% while using the least energy. Flow processes allow to treat large-scale volumes. Our results show that the most efficient flow process for amoeba eradication requires a field parallel to the flow. Pulsed electric fields are a new and attractive method for inactivating amoebae in large volumes of fresh water.

  4. Bopyrid isopods parasitizing on the cultured fresh water prawn, Macrobrachiummalcolmsonii in South India.

    PubMed

    Gopalakrishnan, A; Raja, K; Trilles, J P; Rajkumar, M; Rahman, M M; Saravanakumar, A

    2017-03-01

    The bopyrid isopods are common in wild Macrobrachium spp. but not common in aquaculture condition. This is the first study that reports the parasitizing of bopyrid isopods on the cultured M. malcolmsonii. Bopyrid isopod (Probopyrus buitendijki) was identified in the branchial cavities of the fresh water prawn, M. malcolmsonii from grow-out culture pond at Kuriyamangalam, India. Macrobrachium malcolmsonii is a new host for P. buitendijki. A total of 1323 M. malcolmsonii were checked for this study. The overall prevalence of the parasitic infestation was reached 46.2 %. The parasitic infection was higher in female (83 %) than in male (3.4 %). Highest prevalence of infestation was found in the median size group (7-8 cm) (58.7 %). Infected females were not berried unlike uninfected prawns. The parasites cause infertility and does not found any organ deformities due to the infestation. The parasite was inversely attached in the gill chamber with no lesion on the gill but the infected branchial chamber became bulged.

  5. First record of myxozoan parasites from fresh water fishes of Jammu and Kashmir and their pathogenecity.

    PubMed

    Dar, Shoaib Ali; Kaur, Harpreet; Chishti, M Z

    2017-02-20

    The present study was aimed to isolate myxozoan parasites infecting the native carp Schizothorax esocinus (Heckel) and pond reared carp Labeo rohita (Ham.) collected from fresh water ecosystems of Jammu and Kashmir from July 2013 to June 2014. Various organs such as eyes, gills, scales, fins, intestines, visceral organs and pericardial cavity of as many as 100 live specimens were examined. Results revealed that 14% of the examined L. rohita were infected with Myxobolus rocatlae (Ham.) and 6% of S. esocinus (Heckel) were infected with M. kashmirensis sp. nov. Clinical signs revealed mucous laden gills while the parasitological observation under stereozoom binocular microscope revealed multiple minute plasmodia on the gills. On rupturing these plasmodia with sharp needle 100-500 myxospores were liberated. The identification to species level was done on the basis of morphological and morphometric attributes of the myxospores. This is the first record of myxozoan parasites in fishes from the state of Jammu and Kashmir, India. Histological observations of infected gills revealed plasmodia of two types (LV4 intralamellar vascular type) in M. rocatlae and (LV3 intralamellar vascular type) in M. kasmirensis causing necrosis, hyperplasia, hypertrophy and vacuolization of the epithelial and vascular endothelium.

  6. Non-thermal plasma-activated water inactivation of food-borne pathogen on fresh produce.

    PubMed

    Ma, Ruonan; Wang, Guomin; Tian, Ying; Wang, Kaile; Zhang, Jue; Fang, Jing

    2015-12-30

    Non-thermal plasma has been widely considered to be an effective method for decontamination of foods. Recently, numerous studies report that plasma-activated water (PAW) also has outstanding antibacterial ability. This study presents the first report on the potential of PAW for the inactivation of Staphylococcus aureus (S. aureus) inoculated on strawberries. PAW treatments achieved a reduction of S. aureus ranging from 1.6 to 2.3 log at day-0 storage, while 1.7 to 3.4 log at day-4 storage. The inactivation efficiency depended on the plasma-activated time for PAW generation and PAW-treated time of strawberries inoculated with S. aureus. LIVE/DEAD staining and scanning electron microscopy results confirm that PAW could damage the bacterial cell wall. Moreover, optical emission spectra and oxidation reduction potential results demonstrate the inactivation is mainly attributed to oxidative stress induced by reactive oxygen species in PAW. In addition, no significant change was found in color, firmness and pH of the PAW treated strawberries. Thus, PAW can be a promising alternative to traditional sanitizers applied in the fresh produce industry.

  7. Carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds.

    PubMed

    Anikuttan, K K; Adhikari, S; Kavitha, M; Jayasankar, P

    2016-07-01

    The contribution of aquaculture and allied activities to the emission of green house gases and consequently to global warming is an emerging concern among environmentalists in the recent past. However, there exists ample scope for aquaculture activities to sequester carbon and thus compensate for the carbon emissions linked to aquaculture. This article attempts to elucidate the carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds. The percent organic carbon in the pond sediments ranged from 0.39 to 1.31 with an average value of 0.912 ± 0.321 whereas the carbon sequestration capacity ranged from 0.442 to 1.882 MgC/ha (1 Mg = 10(6) g) with an average value of 1.018 ± 0.447 MgC/ha. In the case of zooplankton and algae from pond, the percent organic carbon was 7.688 ± 0.196 and 2.354 ± 0.047, respectively, whereas the total estimated carbon burial rate was 0.009 ± 0.005 and 0.150 ± 0.003 MgC/ha, respectively. These findings are discussed with the previous reports available at present and are found to be in comparable ranges.

  8. A study on biological control of six fresh water snails of medical and veterinary importance.

    PubMed

    Abd-Allah, Karim F; Negm-Eldin, Mohsen M; Saleh, Mohamed H; El-Hamshary, Azza M S; El-Gozamy, Bothina M R; Aly, Nagwa S M

    2009-04-01

    This study evaluated the molluscicidal effect of Commiphora mnolmol oil extract (Myrrh), on control of six fresh water snails (Lymnaea natalensis, Bulinus truncatus, Biomphalaria alexandrina, Physa acuta, Melania tuberculata and Cleopatra bulimoides). Also, the extract effect on the egg masses of L. natalensis, B. truncatus, B. alexandrina and Ph. acuta was evaluated. Snails and egg masses were exposed at 16-20 degrees C to various concentrations (conc.). LD50 after 24 hours expo-sure were 264/132, 283/195, 230/252, 200/224, 241/246 & 241/246 ppm for young/adult of L. natalensis, B. truncatus, B. alexandrina, Ph. acuta, M. tuberculata and C. bulimnoides respectively. LDtoo after 24 hours exposure were 400/400 for L. natalensis, B. truncatus, B. alexandrina, M. tuberculata and C. bulimoides, and 300/300 for Ph. acuta. Also, complete mortality (100%) was achieved for the egg masses of L. natalensis, B. truncatus, B. alexandrina and Ph. acuta at concentrations of 300, 200, 300 & 400 ppm respectively. Lower concentrations gave the same results after longer exposure. LD100 of C. molmol oil extract (Myrrh) had a rapid lethal effect on the six snail species and their egg masses in high conc. of 300 & 400 ppm. Commiphora molmol is a promising plant to be included with the candidate plant molluscicides. The oil extract of this plant showed a remarkable molluscicidal activity against used snail species.

  9. Ionoregulatory responses of the crayfish Orconectes immunis to selenium in fresh water

    SciTech Connect

    Short, T.M.

    1983-01-01

    The purpose of this study was to investigate the effects of chronic exposure to sublethal concentrations of selenium on fluid and tissue electrolyte balance of the crayfish Orconcectes immunis. An ionic profile of O. immunis was obtained from measurements of hemolymph sodium, potassium, calcium, magnesium, and copper in several populations of crayfish in eastern Colorado. The bioassay portion of the study consisted of groups of crayfish maintained in reconstituted fresh water while exposed for 30 days to concentrations of 0.01 mg/liter, 0.10 mg/liter, or 1.00 mg/liter selenium as sodium selenite. Exposure to selenium resulted in various branchial histopathologies to include hypertrophy, necrosis, and sloughing of the cuticular membrane. Hemolymph potassium and copper, however, were significantly reduced in crayfish exposed for 10 days to 1.00 mg/liter selenium and 30 days to 0.10 mg/liter selenium. Copper appeared to be the more responsive to selenium toxicity with reductions of 47.4%-53.7% in hemolymph levels after exposure for 30 days to 1.00 mg/liter selenium. Selenium-induced changes in tissue ionic content (abdominal muscle and carapace) were most evident with respect to muscle levels of potassium and calcium. It is suggested that the observed alterations in fluid and tissue ionic content are largely in response to changes in concentration or electrochemical potential gradients brought about by selenium-induced disturbance of membrance permeability and ionic transport characteristics.

  10. Chemical and histological studies of wild and hatchery salmon in fresh water

    USGS Publications Warehouse

    Wood, E.M.; Yasutake, W.T.; Halver, J.E.; Woodall, A.N.

    1960-01-01

    In a study of coho salmon (Oncorhynchus kisutch), the gross chemical and histological changes occurring over a 14-month period spent in fresh water were determined. The determinations were made at 3-month intervals on: 1) hatchery-reared fish, 2) fish hatchery-reared for 3, 6, 9, and 12 months and then planted in a controlled stream for the remainder of the period; and 3) an indigenous group of wild fish in this stream. Wild fish showed high incidence of tissue damage from spinose hairs of the moth larva, Halisidota argentata. Hatchery fish were similarly affected with the severity and incidence of lesions varying directly with the time of exposure of the larvae in the wild environment. Both groups of fish were heavily parasitized by sporozoan organisms in the kidney and spinal cord. Kidney disease appeared in both wild and planted hatchery fish. The gross chemical composition of hatchery fish transformed rapidly after planting to that of the wild fish. Although the initial rate of fat loss is essentially constant for all hatchery groups after planting, fish that were hatchery reared for 9 to 12 months did not complete the transformation to the wild-type body composition by the time of downstream migration at 14 months.

  11. Scanning electron microscopic investigations of fresh mortars: Well-defined water-filled layers adjacent to sand grains

    SciTech Connect

    Diamond, S. Kjellsen, K.O.

    2008-04-15

    SEM examinations are reported of freshly-mixed and early age mortar specimens prepared by fast freezing in liquid nitrogen followed by epoxy impregnation, and of companion specimens of early aged mortars prepared conventionally. Freshly-mixed mortars reveal complex features that appear to influence subsequent development of the hardened state microstructure. In particular, layers of entirely water-filled space a few micrometers thick are found adjacent to many of the sand grain surfaces. After a few hours sparse deposits of calcium hydroxide crystals (and later C-S-H) are found within these layers, but the layers persist as recognizable features for at least 12 h. The layers are identically recognizable in both fast-frozen and conventionally-prepared specimens. Another feature found in freshly-mixed mortars is the existence of patchy local areas of sparsely-packed and other areas of densely-packed cement particles.

  12. Prediction of Performance of a Cavitating Propeller in Oblique Inflow

    NASA Astrophysics Data System (ADS)

    Tian, Ye; Kinnas, Spyros A.

    2015-12-01

    A cavitating propeller subject to an oblique inflow in a cavitating tunnel is simulated using potential flow methods coupled with a Reynolds-averaged Navier-Stokes (RANS) solver. The propeller is mainly modelled using a panel method, while the inflow to the propeller is evaluated by coupling a Vortex-Lattice Method (VLM) with the RANS solver. The effects of the tunnel wall are incorporated into the calculated effective inflow to the propeller. The predicted propeller forces and cavity pattern are correlated with experiment. The fully wetted open water characteristics of the propeller predicted by the panel method are presented as well.

  13. Fresh Water Generation from Aquifer-Pressured Carbon Storage: Interim Progress Report

    SciTech Connect

    Aines, R D; Wolery, T J; Hao, Y; Bourcier, W L

    2009-07-22

    This project is establishing the potential for using brine pressurized by Carbon Capture and Storage (CCS) operations in saline formations as the feedstock for desalination and water treatment technologies including nanofiltration (NF) and reverse osmosis (RO). The aquifer pressure resulting from the energy required to inject the carbon dioxide provides all or part of the inlet pressure for the desalination system. Residual brine would be reinjected into the formation at net volume reduction. This process provides additional storage space (capacity) in the aquifer, reduces operational risks by relieving overpressure in the aquifer, and provides a source of low-cost fresh water to offset costs or operational water needs. Computer modeling and laboratory-scale experimentation are being used to examine mineral scaling and osmotic pressure limitations for brines typical of CCS sites. Computer modeling is being used to evaluate processes in the aquifer, including the evolution of the pressure field. This progress report deals mainly with our geochemical modeling of high-salinity brines and covers the first six months of project execution (September, 2008 to March, 2009). Costs and implementation results will be presented in the annual report. The brines typical of sequestration sites can be several times more concentrated than seawater, requiring specialized modeling codes typical of those developed for nuclear waste disposal calculations. The osmotic pressure developed as the brines are concentrated is of particular concern, as are precipitates that can cause fouling of reverse osmosis membranes and other types of membranes (e.g., NF). We have now completed the development associated with tasks (1) and (2) of the work plan. We now have a contract with Perlorica, Inc., to provide support to the cost analysis and nanofiltration evaluation. We have also conducted several preliminary analyses of the pressure effect in the reservoir in order to confirm that reservoir

  14. Effect of a Phenolic Extract from Olive Vegetation Water on Fresh Salmon Steak Quality during Storage.

    PubMed

    Miraglia, Dino; Esposto, Sonia; Branciari, Raffaella; Urbani, Stefania; Servili, Maurizio; Perucci, Simona; Ranucci, David

    2016-09-20

    This study aimed to evaluate the antioxidant and antimicrobial effects of a phenolic extract from olive vegetation water on fresh salmon steaks stored at 4°C under modified atmosphere. Twenty-four salmon steaks were respectively immersed in solutions of the diluted phenolic extract at 1.5 g/L (A), 3 g/L (B), and water only as a control (CTR), packaged within a protective atmosphere (70% carbon dioxide, 25% nitrogen and 5% oxygen) and then stored at 4°C. After 2 h, and 3 and 6 days of storage, the fish samples were analysed for the total viable count, Enterobacteriaceae count, pH, colour (CIE L*a*b* colour system), phenolic composition, atocopherol content, antioxidant activity by 2,2- diphenyl- 1-picrylhydrazyl (DPPH˙) assay, and thiobarbituric reactive substances (TBARS). A 3 g/L phenolic extract contributed positively to the hygienic quality of the salmon by reducing the microbial growth during storage. The treated samples were slightly yellower than the CTR but only at the beginning of storage. The flesh contained 6.2% of the total polyphenols present in the initial solutions, with various percentages of the single fractions. After 6 days storage, the α- tocopherol content in the CTR and A samples was statistically lower than the B group that also showed the lowest DPPH˙ and TBARS values. In conclusion, the phenolic extract increased the microbiological quality and antioxidant concentration and decreased the lipid oxidation of salmon steaks during storage at 4°C under modified atmosphere.

  15. Impacts of different salinities on bacterial biofilm communities in fresh water.

    PubMed

    Zhang, Lei; Gao, Guang; Tang, Xiangming; Shao, Keqiang

    2014-05-01

    Natural and anthropogenic salinization continuously impacts inland aquatic ecosystems. Associated bacterial biofilms respond rapidly to environmental conditions and are potential bioindicators for changes in water quality. This study evaluates the effects of different salinity concentrations (0.3‰-10‰) on bacterial biofilms communities grown in fresh water from Lake Bosten. Bacterial communities associated with biofilms were analyzed using terminal restriction fragment length polymorphism and clone library analyses of 16S rRNA genes. Results indicated that the attached bacterial community composition (ABCC) changed over several weeks of biofilm growth, but all followed similar bacterial successional trends in the different salinity groups. Detailed analysis showed the following. (i) ABCC did not differ (P > 0.05) in the low-salinity groups (0.3‰-3.5‰), which may be related to the lower osmotic pressure and the shorter time scale (weeks) of their present habitats. (ii) There were significant differences between the oligosaline (3.5‰) and saline (10‰) groups (P < 0.05). In particular, genus Flavobacterium became dominant in attached bacterial communities in the saline groups. The higher abundance of genus Flavobacterium was possibly due to the biological and metabolic characteristics of the bacteria. (iii) Some bacterial taxa can maintain the higher abundance within attached bacteria in the entire process of biofilms growth, such as the genera Hydrogenophaga and Methyloversatilis in Betaproteobacteria and the family Sphingomonadaceae in Alphaproteobacteria. These data suggested that the bacterial successional trends within biofilms seem almost unaffected by salinity (0.3‰-10‰), but ABCC in saline groups (10‰) are notably changed.

  16. Effect of a Phenolic Extract from Olive Vegetation Water on Fresh Salmon Steak Quality during Storage

    PubMed Central

    Miraglia, Dino; Esposto, Sonia; Branciari, Raffaella; Urbani, Stefania; Servili, Maurizio; Perucci, Simona; Ranucci, David

    2016-01-01

    This study aimed to evaluate the antioxidant and antimicrobial effects of a phenolic extract from olive vegetation water on fresh salmon steaks stored at 4°C under modified atmosphere. Twenty-four salmon steaks were respectively immersed in solutions of the diluted phenolic extract at 1.5 g/L (A), 3 g/L (B), and water only as a control (CTR), packaged within a protective atmosphere (70% carbon dioxide, 25% nitrogen and 5% oxygen) and then stored at 4°C. After 2 h, and 3 and 6 days of storage, the fish samples were analysed for the total viable count, Enterobacteriaceae count, pH, colour (CIE L*a*b* colour system), phenolic composition, atocopherol content, antioxidant activity by 2,2- diphenyl- 1-picrylhydrazyl (DPPH˙) assay, and thiobarbituric reactive substances (TBARS). A 3 g/L phenolic extract contributed positively to the hygienic quality of the salmon by reducing the microbial growth during storage. The treated samples were slightly yellower than the CTR but only at the beginning of storage. The flesh contained 6.2% of the total polyphenols present in the initial solutions, with various percentages of the single fractions. After 6 days storage, the α- tocopherol content in the CTR and A samples was statistically lower than the B group that also showed the lowest DPPH˙ and TBARS values. In conclusion, the phenolic extract increased the microbiological quality and antioxidant concentration and decreased the lipid oxidation of salmon steaks during storage at 4°C under modified atmosphere. PMID:28058250

  17. Slightly acidic electrolyzed water combined with chemical and physical treatments to decontaminate bacteria on fresh fruits.

    PubMed

    Tango, Charles Nkufi; Khan, Imran; Ngnitcho Kounkeu, Paul-François; Momna, Rubab; Hussain, Mohammad Shakhawat; Oh, Deog-Hwan

    2017-10-01

    Effect of sequential combination of slightly acidic electrolyzed water (SAEW) with chemical and physical treatments on bacterial decontamination on fruits was investigated in this study. Effect of treatments on microbial and sensory quality was also analyzed after subsequent storage at 4 °C and room temperature (RT, 23 ± 0.15 °C). Whole apple and tomato fruits were inoculated with cocktail strains of Escherichia coli O157:H7 and Listeria monocytogenes. Uninoculated and inoculated fruits were washed first with distilled water (DW), calcium oxide (CaO), fumaric acid (FA), and SAEW at RT for 3 min. Combinations were performed by adding treatment one at a time to SAEW as following FA + SAEW, CaO + FA + SAEW, and CaO + FA + SAEW + ultrasonication (US) or microbubbles (MB). All the sanitizer treatments resulted in significant (p < 0.05) bacterial reduction compared to DW used as control. Increasing the treatments in combination from FA + SAEW to CaO + FA + SAEW + US resulted in an increased bacterial decontamination. The cavitation induced by ultrasonication in FA + SAEW solution resulted in a higher additive effect in decontamination of Escherichia coli O157:H7 and Listeria monocytogenes compare to the agitation generated by microbubble generator in FA + SAEW solution. CaO + FA + SAEW and CaO + FA + SAEW + US were effective in improving the microbial safety and quality of apple fruits. However, additional treatment of US impacted on the quality of tomato fruits during storage at RT. Therefore, a combination of SAEW with sanitizers (CaO and FA) and mechanical force (Ultrasonication) has the potential to be used in postharvest sanitation processing in the fresh fruit industry. Published by Elsevier Ltd.

  18. Fresh-water lenses and practical limitations of their three-dimensional simulation

    NASA Astrophysics Data System (ADS)

    Ghassemi, F.; Alam, K.; Howard, K. W. F.

    2000-10-01

    Fresh-water lenses are the major sources of water supply in many atoll islands in the Pacific and Indian Oceans, particularly in dry seasons. Several two- and three-dimensional models are currently available for the simulation of atoll-island aquifers; however, 2D models cannot include 3D spatial variability of material properties, they must simplify the boundary conditions, and they cannot correctly simulate pumping wells. In an attempt to overcome these difficulties, a 3D model, SALTFLOW, was adopted for the simulation of Home Island in the Indian Ocean. This exercise required a discretisation on the order of a few metres and time steps of a few hours requiring significantly high CPU times. High CPU demand proved to be a difficult challenge but cannot be considered a serious practical limitation with today's advanced computers. The exhaustive data demands of the model (e.g., 3D distributions of hydraulic conductivity, porosity, dispersivities, and spatial and temporal variations of recharge and extraction rates) proved to be more problematical. Although the Home Island data set is unusually comprehensive by any standards, nonetheless the quality and quantity of the available data proved inadequate to meet the calibration needs of a highly karstic aquifer system. The Home Island modeling demonstrates the practical limitations of 3D models. It raises the concern that our ability to develop computer codes capable of simulating complex systems now exceeds our ability to supply the input data necessary for reliable calibration. Finally, the paper demonstrates the importance of the transient calibration in reliable simulation of various management options and emphasises that transient calibration should be considered as an integral part of any similar 2D or 3D modeling.

  19. Groundwater inflow measurements in wetland systems

    USGS Publications Warehouse

    Hunt, R.J.; Krabbenhoft, D.P.; Anderson, M.P.

    1996-01-01

    Our current understanding of wetlands is insufficient to assess the effects of past and future wetland loss. While knowledge of wetland hydrology is crucial, groundwater flows are often neglected or uncertain. In this paper, groundwater inflows were estimated in wetlands in southwestern Wisconsin using traditional Darcy's law calculations and three independent methods that included (1) stable isotope mass balances, (2) temperature profile modeling, and (3) numerical water balance modeling techniques. Inflows calculated using Darcy's law were lower than inflows estimated using the other approaches and ranged from 0.02 to (0.3 cm/d. Estimates obtained using the other methods generally were higher (0.1 to 1.1 cm/d) and showed similar spatial trends. An areal map of groundwater flux generated by the water balance model demonstrated that areas of both recharge and discharge exist in what is considered a regional discharge area. While each method has strengths and weaknesses, the use of more than one method can reduce uncertainty in the estimates.

  20. The effect of soil water repellency on water and chemicals distribution in the soil profile for effluent and fresh water irrigation

    NASA Astrophysics Data System (ADS)

    Wallach, Rony; Rahav, Matan; Brindt, Naaran; Furman, Alex

    2015-04-01

    Water repellency (WR) has been reported for many vegetation types and soils and for effluent irrigation. Citrus trees have been found in a previous and in the current study to render sandy soils hydrophobic. The presented study focuses on the synergistic effect of the uneven wetting patterns and preferential flow pathways, known to occur in WR soils, and irrigation water quality on the spatial distribution of salinity and nutrients in the citrus trees' root zone. The study was performed in a commercial grapefruit orchard that is located at the coastal plain of Israel. The soil is sandy (80 % sand, 9 % silt and 11% clay). An experimental orchard area of 1500 m2 was divided into ten plots - five are irrigated with fresh water and five with secondary treated sewage water (effluent) using a drip irrigation system. Each plot contains 12 trees with spacing of 2x6 m. Soil texture, water repellency persistence (WDPT), and OM were measured for all 10 plots. The spatial and temporal water content distribution in the trees' root zone during and between subsequent irrigation events was measured undisturbedly by the electrical resistivity tomography (ERT) method. Soil water content within the root zone was indeed found highly heterogeneous in space and in time. Using ERT scans, two sites with relatively wet soil underneath and two with relatively dry soil underneath were chosen in each plot for further investigation. Disturbed soil samples from two depths, 0-20 and 20-40 cm, were taken from each site and tested in the laboratory for weight-based saturation, current water content, pH, EC, Cl, Na, Mg, NO3, P, K, and OM. The overall finding was that the uneven distribution of water content in the water repellent soil has a substantial effect on the salinity and nutrients distribution in the soil profile. Higher salinity and nutrients concentrations were found in the effluent irrigated plots compared to the fresh water plots. In particular, salinity was higher in the dry spots and

  1. Detection of fresh ground water and a contaminant plume beneath Red Brook Harbor, Cape Cod, Massachusetts, 2000

    USGS Publications Warehouse

    McCobb, Timothy D.; LeBlanc, Denis R.

    2002-01-01

    Trichloroethene and tetrachloroethene were detected in ground water in a vertical interval from about 68 to 176 feet below sea level beneath the shoreline where the contaminant plume emanating from a capped landfill on the Massachusetts Military Reservation intersects Red Brook Harbor. The highest concentrations at the shoreline, about 15 micrograms per liter of trichloroethene and 1 microgram per liter of tetrachloroethene, were measured in samples from one well at about 176 feet below sea level. The concentrations of nutrients, such as nitrate and ammonium, and trace metals, such as iron and manganese, in these same samples are typical of uncontaminated ground water on Cape Cod. Fresh ground water (bulk electrical conductance less than 100 millisiemens per meter) is present beneath the harbor at 40 of 48 locations investigated within about 250 feet of the shoreline. Fresh ground water also was detected at one location approximately 450 feet from shore. The harbor bottom consists of soft sediments that range in thickness from 0 to greater than 20 feet and overlie sandy aquifer materials. Trichloroethene was detected at several locations in fresh ground water from the sandy aquifer materials beneath the harbor. The highest trichloroethene concentration, about 4.5 micrograms per liter, was measured about 450 feet from shore.

  2. EFFICIENT RECOVERY OF ENTEROCOCCI FROM MARINE AND FRESH WATER BEACHES BY A 30,000 MOLECULAR WEIGHT CUTOFF HOLLOW FIBER ULTRAFILTER

    EPA Science Inventory

    Ultrafiltration systems have been used to concentrate pathogens from various types of fresh water samples. However, less work has been done with marine waters for the concentration of pathogens or indicator bacteria. An ultrafiltration approach to concentrate indicator bacteria...

  3. EFFICIENT RECOVERY OF ENTEROCOCCI FROM MARINE AND FRESH WATER BEACHES BY A 30,000 MOLECULAR WEIGHT CUTOFF HOLLOW FIBER ULTRAFILTER

    EPA Science Inventory

    Ultrafiltration systems have been used to concentrate pathogens from various types of fresh water samples. However, less work has been done with marine waters for the concentration of pathogens or indicator bacteria. An ultrafiltration approach to concentrate indicator bacteria...

  4. Disinfection potential of ozone, ultraviolet-C and their combination in wash water for the fresh-cut vegetable industry.

    PubMed

    Selma, María V; Allende, Ana; López-Gálvez, Francisco; Conesa, María A; Gil, María I

    2008-09-01

    The purpose of this research was to investigate the disinfection efficacy of ozone (O(3)) and UV-C illumination (UV), and their combination (O(3)-UV) for reducing microbial flora of fresh-cut onion, escarole, carrot, and spinach wash waters collected from the industry. Furthermore, the influence of water physicochemical parameters on the decontamination efficacy and the effect of these technologies on physicochemical quality of wash water were analyzed. O(3), UV, and O(3)-UV were effective disinfection treatments on vegetable wash water, with a maximum microbial reduction of 6.6 log CFU mL(-1) after 60 min treatment with O(3)-UV. However, maximum total microbial reductions achieved by UV and O(3) treatments after 60 min were 4.0 and 5.9 log CFU mL(-1), lower than by O(3)-UV treatment. Furthermore, turbidity of wash water was reduced significantly by O(3) and O(3)-UV treatments, while UV treatment did not affect the physicochemical quality of the water. Conclusions derived from this study illustrate that O(3) and O(3)-UV are alternatives to other sanitizers used in the fresh-cut washing processes. The use of these technologies would allow less frequent changing of spent water and the use of much lower sanitizer doses. Nevertheless, in specific applications such as carrot wash water, where levels of undesirable microbial and chemical constituents are lower than other vegetable wash water, UV treatment could be an appropriate treatment considering cost-effectiveness criteria.

  5. Comparison of metal lability in air-dried and fresh dewatered drinking water treatment residuals.

    PubMed

    Wang, Changhui; Pei, Yuansheng; Zhao, Yaqian

    2015-01-01

    In this work, the labilities of Al, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr, V and Zn in air-dried (for 60 days) and fresh dewatered WTRs were compared using the Toxicity Characteristic Leaching Procedure (TCLP), fractionation, in vitro digestion and a plant enrichment test. The results showed that the air-dried and fresh dewatered WTRs had different properties, e.g., organic matter composition and available nutrients. The air-dried and fresh dewatered WTRs were non-haf zardous according to the TCLP assessment method used in the United States; however, the metals in the two types of WTRs had different lability. Compared with the metals in the fresh dewatered WTRs, those in the air-dried WTRs tended to be in more stable fractions and also exhibited lower bioaccessibility and bioavailability. Therefore, air-drying can decrease the metal lability and thereby reduce the potential metal pollution risk of WTRs.

  6. Arctic Fresh Water Export and its Impact on Climate in the 20th and 21st Century

    NASA Astrophysics Data System (ADS)

    Koenigk, T.; Mikolajewicz, U.; Haak, H.; Jungclaus, J.

    2005-12-01

    Coupled IPCC experiments with the Max-Planck-Institute climate model ECHAM5/MPI-OM are used to analyse the changes in the fresh water export out of the Arctic. Furthermore, the impacts of these changes on climate are investigated. In the 20th century, 57 % of the simulated Arctic fresh water export (reference salinity is 34.8) into the North Atlantic Ocean takes place through Fram Strait, 32 % through the Canadian Archipelago and 11 % over the Barents Shelf. The variability is mainly governed by the ice export through Fram Strait and is highly affected by the atmospheric circulation. Large ice exports provoke a dramatic reduction in Labrador Sea surface salinity in the following years. Oceanic convection is decreased and ice cover is increased. As a consequence, the heat flux from ocean to atmosphere is below normal, which leads to significant negative temperature anomalies in the Labrador Sea. In the 21st century, our model results show a reduction of sea ice volume and an increase of precipitation and Arctic rivers runoff. Most of this additional fresh water is stored in the Arctic Ocean. The total Arctic fresh water export is only slightly changing until year 2100. However, a redistribution of the export occurs: The solid part becomes much smaller with time and plays no significant role anymore at the end of the 21st century. At the same time the fluid part increases. The export through the Canadian Archipelago rises by 0.025 Sverdrup, while the export over the Barents Shelf is reduced by 0.02 Sverdrup. The amount of fresh water exported through Fram Strait stays constant but the interannual variability is decreased by 25 %. The impact of the export through Fram Strait on Labrador Sea climate is thus strongly reduced. In contrast, the export through the Canadian Archipelago gains importance. The convection is reduced by about 40 % in the Greenland Sea and 60 % in the Labrador Sea. The reduction in the Labrador Sea can be explained by increased fresh water export

  7. Is the fresh water fish consumption a significant determinant of the internal exposure to perfluoroalkylated substances (PFAS)?

    PubMed

    Denys, Sébastien; Fraize-Frontier, Sandrine; Moussa, Oumar; Le Bizec, Bruno; Veyrand, Bruno; Volatier, Jean-Luc

    2014-12-01

    PFAS are man-made compounds that are highly spread in the environment. Human dietary exposure to such contaminants is of high concern as they may accumulate in the food chain. Different studies already demonstrated the importance of the fish consumption in the dietary exposure of these molecules and the potential increase of internal doses of PFAS following the consumption of PFAS. However, so far few study aimed to study the link between the consumption of fresh water fishes and the internal exposure to PFAS. Objectives of this study were (i) to estimate the internal exposure of populations that are potentially high consumers of fresh water fishes and (ii) to determine whether the consumption of fish caught from fresh water is a significant determinant of the internal exposure of PFAS. In this work, a large sample of adult freshwater anglers from the French metropolitan population (478 individuals) was constituted randomly from participants lists of anglers associations. Questionnaires provided social and demographic information and diet information for each subject. In addition, analyses of blood serum samples provided the internal concentration of 14 PFAS. The survey design allowed to extrapolate the data obtained on the 478 individuals to the freshwater angler population. Descriptive data regarding internal levels of PFAS were discussed at the population level, whereas identification of the determinants were done at the 478 individuals level as sufficient contrast was required in terms of fresh water fish consumption. Only molecules for which the detection frequency were above 80% in blood were considered, i.e., PFOS, PFOA, PFHxS, PFNA, PFHpS, and PFDA. Distribution profiles showed log-normal distribution and PFOS and PFOA were the main contributors of the PFAS sum. For PFOS, the results obtained on the 478 individuals showed that upper percentiles were higher as compared to upper percentiles obtained on occidental general population. This confirmed an over

  8. Water in barnacle muscle. III. NMR studies of fresh fibers and membrane-damaged fibers equilibrated with selected solutes.

    PubMed Central

    Burnell, E E; Clark, M E; Hinke, J A; Chapman, N R

    1981-01-01

    Water in barnacle muscle has been studied using NMR techniques. Fresh fibers are compared with membrane-damaged fibers treated with solutes that greatly alter fixed charge and total water content. Both water (97%) and solute (3%) protons are visible in continuous wave spectra of oriented fresh fibers. No local field inhomogeneities were detected, nor are cell solutes significantly bound. In pulse experiments, all cell water is visible and exhibits a single exponential decay. In fresh fibers, T2 approximately or equal to 40 ms; faster decaying signals are assigned to immobile and mobile protons on macromolecules. T1 and T1p are frequency dependent. Using equations derived for a two-compartment model with fast exchange, we calculate the following: tau b, the correlation time for anisotropic rotational motion of bound water; Sb, its order parameter; tau ex, the correlation time for exchange between bound and free fractions; f, the fraction of water bound; and Hr, the grams of water bound per gram of macromolecule. Whereas f varies inversely with total water content, the other parameters are virtually constant, with values: tau b approximately or equal to 1.3 X 10(-8) S; tau ex approximately or equal to 8 X 10(-6) s; Sb approximately or equal to 0.06; and Hr approximately or equal to 0.1g H2O/g macromolecule. Thus, the NMR relaxation detectable properties of water bound to macromolecules are unaffected by solutes that greatly alter the macromolecular surface charge. PMID:7272435

  9. Assessment of the fresh-and brackish-water resources underlying Dunedin and adjacent areas on northern Pinellas County, Florida

    USGS Publications Warehouse

    Knochenmus, L.A.; Swenson, E.S.

    1996-01-01

    The city of Dunedin is enhancing their potable ground-water resources through desalination of brackish ground water. An assessment of the fresh- and brackish-water resources in the Upper Floridan aquifer was needed to estimate the changes that may result from brackish-water development. The complex hydrogeologic framework underlying Dunedin and adjacent areas of northern Pinellas County is conceptualized as a multilayered sequence of permeable zones and confining and semiconfining units. The permeable zones contain vertically spaced, discrete, water-producing zones with differing water quality. Water levels, water-level responses, and water quality are highly variable among the different permeable zones. The Upper Floridan aquifer is best characterized as a local flow system in most of northern Pinellas County. Pumping from the Dunedin well field is probably not influencing water levels in the aquifer outside Dunedin, but has resulted in localized depressions in the potentiometric surface surrounding production-well clusters. The complex geologic layering combined with the effects of production-well distribution probably contribute to the spatial and temporal variability in chloride concentrations in the Dunedin well field. Chloride concentrations in ground water underlying the Dunedin well field vary both vertically and laterally. In general, water-quality rapidly changes below depths of 400 feet below sea level. Additionally, randomly distributed water-producing zones with higher chloride concentrations may occur at shallow, discrete intervals above 400 feet. A relation between chloride concentration and distance from St. Joseph Sound is not apparent; however, a possible relation exists between chloride concentration and production-well density. Chloride-concentration data from production wells show a consistently increasing pattern that has accelerated since the late 1980's. Chloride-concentration data from 15 observation wells show increasing trends for 6 wells

  10. Influence of conjunctive use of coffee effluent and fresh water on performance of robusta coffee and soil properties.

    PubMed

    Salakinkop, S R; Shivaprasad, P

    2012-01-01

    A field experiment was conducted to study the influence of treated coffee effluent irrigation on performance of established robusta coffee, nutrient contribution and microbial activities in the soil. The results revealed that the field irrigated with coffee effluent from aerobic tank having COD of 1009 ppm, did not affect the yield of clean coffee (1309 kg/ha) and it was statistically similar (on par) with the plots irrigated with fresh water (1310 kg/ha) with respect to clean coffee yield. Effluent irrigation increased significantly the population bacteria, yeast, fungi, actinomycetes and PSB (122, 52, 12, 34 and 6 x 104/g respectively)) in the soil compared to the soil irrigated with fresh water (87, 22, 5, 24 and 2 x 10(4)/g respectively). The organic carbon (2.60%), available nutrients in the soil like P (57.2 kg/ha), K (401.6 kg/ha, Ca (695.3 ppm), S (5.3 ppm),Cu (4.09 ppm) and Zn(4.78 ppm) were also increased due to effluent irrigation compared to fresh water irrigation. Thus analysis of coffee effluent for major and minor plant nutrients content revealed its potential as source of nutrients and water for plant growth.

  11. Adaptive patterns of osmotic and ionic regulation, and the invasion of fresh water by the palaemonid shrimps.

    PubMed

    Freire, Carolina A; Cavassin, Fabiola; Rodrigues, Ellen N; Torres, Antonio H; McNamara, John C

    2003-11-01

    To evaluate trends in the osmoregulatory behavior of neotropical, palaemonid shrimps, we investigated osmotic and ionic regulatory patterns in five species of Palaemon or Macrobrachium. The species' life histories depend on saline water to differing degrees, their habitats ranging from the marine/intertidal (P. northropi), through estuaries (P. pandaliformis) to coastal, freshwater streams (M. olfersii, M. potiuna) and inland, continental river systems (M. brasiliense). Hemolymph osmolality, chloride, sodium and magnesium concentrations were measured in shrimps exposed to experimental media ranging from fresh water (<0.5 per thousand ) to concentrated seawater (42 per thousand ) for up to 10 days. The marine and estuarine Palaemon species exhibit well-developed hyper/hypo-osmotic, sodium and chloride regulatory capabilities in mid-range salinities, tending to hyperconform in low salinities. The freshwater Macrobrachium species show variable hyperosmotic, sodium and chloride regulatory capacities, tending to hypoconform or unable to survive at higher salinities. All species hyper-regulate magnesium in fresh water, but hyporegulate strongly in saline media. Palaemonids from the saline habitats show the strongest osmoregulatory capabilities, and fresh water may have been gradually invaded by ancestral species with similar regulatory capacity. However, this regulatory plasticity has been lost to varying degrees in extant freshwater species.

  12. Production of Potent Antimicrobial Compounds from Streptomyces cyaneofuscatus Associated with Fresh Water Sediment

    PubMed Central

    Zothanpuia; Passari, Ajit K.; Chandra, Preeti; Leo, Vincent V.; Mishra, Vineet K.; Kumar, Brijesh; Singh, Bhim P.

    2017-01-01

    The genus Streptomyces under phylum actinobacteria has been recognized as a prolific source for the production of bioactive secondary metabolites. An actinobacterial strain designated as DST103 isolated from a wetland fresh water sediment of Tamdil Lake, Mizoram, Northeast, India was identified as Streptomyces cyaneofuscatus (KY287599) using 16SrRNA gene sequencing which shares 99.87% sequence similarity with Streptomyces cyaneofuscatus NRRL B-2570T. The strain showed broad spectrum antimicrobial activities against Gram negative bacteria (Escherichia coli MTCC 739 and Pseudomonas aeruginosa MTCC 2453), Gram positive bacteria (Micrococcus luteus NCIM 2170 and Staphylococcus aureus MTCC 96) and yeast pathogen Candida albicans MTCC 3017). The methanolic extract of the strain DST103 exhibited highest antimicrobial activity against E. coli (IC50 = 2.10 μg/mL) and minimum activity against S. aureus (IC50 = 43.63 μg/mL). Five antibiotics [trimethoprim (18 μg/g), fluconazole (6 μg/g), ketoconazole (18 μg/g), nalidixic acid (135 μg/g), and rifampicin (56 μg/g)] were detected and quantified using ultra-performance liquid chromatography (UPLC-ESI-MS/MS). Further, biosynthetic potential genes [polyketide synthases type II, non-ribosomal peptide synthetases, and aminodeoxyisochorismate synthase (phzE)] were also detected in strain DST103 which may possibly be responsible for the production of antimicrobial compounds. Additionally, gas chromatography-mass spectrometry analysis showed the presence of four volatile compounds which might be responsible for their diverse biological activity. The present study revealed the presence of bioactive compounds in strain DST103, which may be a promising resource for the discovery of novel bioactive metabolites against wide range of pathogens. PMID:28179900

  13. Fresh water acclimation elicits a decrease in plasma corticosteroids in the euryhaline Atlantic stingray, Dasyatis sabina.

    PubMed

    Evans, Andrew N; Nunez, B Scott

    2015-10-01

    It is thought that the elasmobranch corticosteroid hormone 1α-hydroxycorticosterone (1α-B) functions as both a glucocorticoid (GC) and mineralocorticoid (MC). Classical antinatriuretic MC activities would run counter to the osmoregulatory strategy of euryhaline elasmobranchs acclimating to fresh water (FW). Therefore we hypothesize that FW acclimation will be accompanied by a decrease in plasma corticosteroids in these animals. However, events that activate the "fight-or-flight" response could mask changes associated with acclimation to lower salinities. To better define the MC role of corticosteroids in elasmobranchs, we designed a transfer system that allows the acclimation of Atlantic stingrays (Dasyatis sabina) from seawater (SW) to FW over 12h while minimizing other extraneous stressors. Blood and interrenal glands were sampled from one group of stingrays 24h after FW transfer, while another group was sampled two weeks after FW transfer. Two other groups served as mock-transfer controls in that they were treated and sampled in the same way, but remained in SW for the entire period. Plasma corticosteroids, osmolality, chloride, and urea were significantly lower in FW-acclimated stingrays (compared to mock-transfer stingrays) 24h after FW transfer. This pattern remained after two weeks in FW, with the exception that plasma corticosteroids returned to pre-acclimation levels. There were no significant differences between experimental groups in interrenal levels of mRNAs encoding key steroidogenic proteins (steroidogenic acute regulatory protein and cholesterol side chain cleavage enzyme). Temporally decreased corticosteroid levels during FW acclimation are consistent with the unique strategy of euryhaline elasmobranchs, whereby lower plasma osmolality is maintained in FW vs. SW environments to reduce hydromineral gradients. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Flavobacterium anatoliense sp. nov., isolated from fresh water, and emended description of Flavobacterium ceti.

    PubMed

    Kacagan, Murat; Inan, Kadriye; Belduz, Ali Osman; Canakci, Sabriye

    2013-06-01

    A Gram-staining-negative, catalase- and oxidase-positive, strictly aerobic, rod-shaped bacterial strain isolated from fresh water in Trabzon, Turkey and designated MK3(T) was characterized by phenotypic and molecular methods in order to determine its phylogenetic position. On the basis of 16S rRNA gene sequence similarity, strain MK3(T) was shown to belong to the genus Flavobacterium, being most closely related to Flavobacterium ceti CECT 7184(T) (93.6%). Sequence similarity with other species of the genus Flavobacterium with validly published names was less than 91.6%. Phenotypic and chemotaxonomic data supported the affiliation of strain MK3(T) to the genus Flavobacterium. The only menaquinone was MK-6; the major fatty acids were iso-C15:0 (45.2%), summed feature 9 (C16:0 10-methyl and/or iso-C17:1ω9c; 20.4%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c; 13.3%) and the major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid and two unidentified phospholipids. The G+C content of the genomic DNA was 38.6 mol%. The results of physiological and biochemical tests allowed strain MK3(T) to be distinguished phenotypically from Flavobacterium ceti CECT 7184(T). Strain MK3(T), therefore, represents a novel species of the genus Flavobacterium, for which the name Flavobacterium anatoliense sp. nov. is proposed. The type strain is MK3(T) (=LMG 26441(T)=NCCB 100384(T)). An emended description of Flavobacterium ceti is also proposed.

  15. Polychlorinated dibenzodioxins, dibenzofurans, and biphenyls in fresh water fish from Campania Region, southern Italy.

    PubMed

    Pacini, N; Abate, V; Brambilla, G; De Felip, E; De Filippis, S P; De Luca, S; di Domenico, A; D'Orsi, A; Forte, T; Fulgenzi, A R; Iacovella, N; Luiselli, L; Miniero, R; Iamiceli, A L

    2013-01-01

    Twenty-eight fish muscle specimens from the main water bodies of the Campania Region were analyzed in our laboratory. On average, results showed a low contamination by PCDDs+PCDFs and a relatively more important presence of DL-PCBs. All specimens were compliant with EU regulatory maximum levels. Cumulative PCDD+PCDF+DL-PCB concentrations (TEQ(TOT)) were comprised in the range 0.223-11.4 pgWHO(97)-TEQ g(-1) fresh weight (fw). DL-PCB contribution to TEQ(TOT) was on average greater than 86% (range, 50.2-97.1%). The cumulative concentrations of 30 non-dioxin-like PCB congeners (Σ(30)(NDL-PCBs)) and of the six indicators (Σ(6)(NDL-PCBs)) were respectively in the ranges 3.30-515 and 1.30-195 ng g(-1) fw. The hybrid clustering approach adopted to analyze the sample-specific congener profiles indentified the main analytical patterns present in the database and, in particular, two main diverse exposure macro-areas that seem to exist north and south of the city of Naples. The distribution of PCDD and PCDF congeners among different species showed significant variations from chub (Leuciscus cephalus), characterized by a higher proportion of low-chlorinated congeners (e.g. 2,3,7,8-T(4)CDD), to eel (Anguilla anguilla), whose contamination consisted mainly of highly chlorinated congeners (e.g. O(8)CDD). To have a more complete perspective in relation to the contaminants present in the environment, the study suggestion is to use benthic as well as pelagic species to obtain an integrated characterization of fish tissue contamination.

  16. Determination of trace vanadium (V) in seawater and fresh water by the catalytic kinetic spectrophotometric method

    NASA Astrophysics Data System (ADS)

    Ji, Hongwei; Sha, Yuanyuan; Xin, Huizhen; Li, Shuang

    2010-12-01

    A new kinetic spectrophotometric method has been developed for the determination of vanadium (V). The method is based on the catalytic effect of vanadium (V) on the oxidation of weak acid brilliant blue dye (RAWL) by KBrO3 using the citric acid as activation reagent. The obtained optimum conditions are: c (RAWL) = 1×10-4 molL-1, c (KBrO3) = 3×10-2 molL-1, c (citric acid) = 9×10-3 molL-1, pH = 2.50, the reaction time being 7.0 min and the temperature being 25.0°C. Under the optimum conditions, the proposed method allows the determination of vanadium (V) in the range of 0-70.0 ng mL-1 and the detection limit is down to 0.407 ng mL-1. For standard vanadium (V) solution determination, the recovery efficiency is in the range of 98.5%-102% and the RSD ranges from 0.76%-1.25%. Moreover, it is demonstrated that most cations and anions do not interfere with the determination of vanadium (V) under the analytical condition. The new method was successfully applied in the determination of vanadium (V) in fresh water and seawater samples with satisfactory results. Vanadium (V) in the seawater samples from Qingdao offshore was determined using the method and the distribution of vanadium (V) was mapped. Compared with other instrumental analytical methods, the proposed method shows good selectivity, sensitivity, simplicity, lower cost and rapidity. It can be employed on shipboard easily.

  17. Biochemical composition of some small indigenous fresh water fishes from the River Mouri, Khulna, Bangladesh.

    PubMed

    Kamal, D; Khan, A N; Rahman, M A; Ahamed, F

    2007-05-01

    Biochemical composition of seven small indigenous fresh water fishes namely Magur (Clarias batrachus), Shingi (Heteropneustes fossilis), Koi (Anabas testudineus), Foli (Notopterus notopterus), Royna (Nandas nandas), Taki (Channa punctatus) and Tangra (Mystus vittatus) from the Mouri river Khulna, Bangladesh was studied in order to evaluate their nutritional values. The mean value of protein, fat, moisture and ash content was found as 14.87 +/- 0.63, 7.90 +/- 1.91, 73.49 +/- 0.69 and 3.74 +/- 0.46% in C. batrachus; 17.34 +/- 0.51, 3.45 +/- 0.92, 76.06 +/- 2.24 and 3.15 +/- 0.25% in H. fossilis; 19.63 +/- 0.5, 7.79 +/- 2.73, 69.27 +/- 1.04 and 3.31 +/- 0.83% in A. testudineus; 18.30 +/- 0.79, 4.98 +/- 1.71, 72.68 +/- 1.08 and 5.82 +/- 0.82% in N. notopterus; 16.09 +/- 2.66, 7.34 +/- 0.49, 75.75 +/- 0.78 and 5.19 +/- .029% in N. nandas; 19.13 +/- 2.40, 4.55 +/- 1.18, 70.55 +/- 1.89 and 6.81 +/- 0.94% in C. punctatus and 15.62 +/- 0.32, 7.53 +/- 1.10, 73.99 +/- 3.13 and 6.50 +/- 0.63% in M. vittatus. Considering the result of the present study, it can be concluded that all the species are rich in food value.

  18. Bacterial concentration and diversity in fresh tropical shrimps (Penaeus notialis) and the surrounding brackish waters and sediment.

    PubMed

    Dabadé, D Sylvain; Wolkers-Rooijackers, Judith C M; Azokpota, Paulin; Hounhouigan, D Joseph; Zwietering, Marcel H; Nout, M J Rob; den Besten, Heidy M W

    2016-02-02

    This study aimed at determining bacterial concentration and diversity in fresh tropical shrimps (Penaeus notialis) and their surrounding brackish waters and sediment. Freshly caught shrimp, water and sediment samples were collected in Lakes Nokoue and Aheme in Benin (West Africa) during two periods with different water salinity and temperature. We used complementary culture-dependent and culture-independent methods for microbiota analysis. During both sampling periods, total mesophilic aerobic counts in shrimp samples ranged between 4.4 and 5.9 log CFU/g and were significantly higher than in water or sediment samples. In contrast, bacterial diversity was higher in sediment or water than in shrimps. The dominant phyla were Firmicutes and Proteobacteria in shrimps, Firmicutes, Proteobacteria, and Actinobacteria in water, and Proteobacteria and Chloroflexi in sediment. At species level, distinct bacterial communities were associated with sediment, water and shrimps sampled at the same site the same day. The study suggests that the bacterial community of tropical brackish water shrimps cannot be predicted from the microbiota of their aquatic environment. Thus, monitoring of microbiological quality of aquatic environments might not reflect shrimp microbiological quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Acid precipitation: Effects on fresh-water ecosystems. April 1978-January 1990 (A Bibliography from the Life Sciences Collection data base). Report for April 1978-January 1990

    SciTech Connect

    Not Available

    1990-06-01

    This bibliography contains citations concerning the effects of acidification on fresh water ecosystems. Algae and diatom distribution, survival and reproduction rates of specific fish species under acid lake conditions, and tolerance to stress caused by acidic conditions in fresh water ecosystems are studied. Effects of water pH on trace metal toxicity to fresh water organisms are briefly considered. Control and reduction of acidification are excluded from this bibliography. (This updated bibliography contains 331 citations, 41 of which are new entries to the previous edition.)

  20. SEQUESTERING AGENTS FOR METAL IMMOBILIZATION APPLICATION TO THE DEVELOPMENT OF ACTIVE CAPS IN FRESH AND SALT WATER SEDIMENTS

    SciTech Connect

    Knox, A; Michael Paller, M

    2006-11-17

    This research evaluated the removal of inorganic contaminants by a variety of amendments and mixtures of amendments in fresh and salt water. A series of removal and retention batch experiments was conducted to identify the best treatment for metal removal. Metal removal by the amendments was evaluated by calculating the partition coefficient and percent removal. Retention of metals by the amendments was evaluated in retention (desorption) studies in which residue from the removal studies was extracted with 1 M MgCl{sub 2} solution. The results indicated that phosphate amendments, some organoclays (e.g., OCB-750), and the biopolymer, chitosan, are very effective in removal and retention of metals in both fresh and salt water. These amendments are being evaluated further as components in the development of active caps for sediment remediation.

  1. Harvesting fresh water and marine algae by magnetic separation: screening of separation parameters and high gradient magnetic filtration.

    PubMed

    Cerff, Martin; Morweiser, Michael; Dillschneider, Robert; Michel, Aymeé; Menzel, Katharina; Posten, Clemens

    2012-08-01

    In this study, the focus is on magnetic separation of fresh water algae Chlamydomonas reinhardtii and Chlorella vulgaris as well as marine algae Phaeodactylum tricornutum and Nannochloropsis salina by means of silica-coated magnetic particles. Due to their small size and low biomass concentrations, harvesting algae by conventional methods is often inefficient and cost-consuming. Magnetic separation is a powerful tool to capture algae by adsorption to submicron-sized magnetic particles. Hereby, separation efficiency depends on parameters such as particle concentration, pH and medium composition. Separation efficiencies of >95% were obtained for all algae while maximum particle loads of 30 and 77 g/g were measured for C. reinhardtii and P. tricornutum at pH 8 and 12, respectively. This study highlights the potential of silica-coated magnetic particles for the removal of fresh water and marine algae by high gradient magnetic filtration and provides critical discussion on future improvements.

  2. Design of a proteus lattice representative of a burnt and fresh fuel interface at power conditions in light water reactors

    SciTech Connect

    Hursin, M.; Perret, G.

    2012-07-01

    The research program LIFE (Large-scale Irradiated Fuel Experiment) between PSI and Swissnuclear has been started in 2006 to study the interaction between large sets of burnt and fresh fuel pins in conditions representative of power light water reactors. Reactor physics parameters such as flux ratios and reaction rate distributions ({sup 235}U and {sup 238}U fissions and {sup 238}U capture) are calculated to estimate an appropriate arrangement of burnt and fresh fuel pins within the central element of the test zone of the zero-power research reactor PROTEUS. The arrangement should minimize the number of burnt fuel pins to ease fuel handling and reduce costs, whilst guaranteeing that the neutron spectrum in both burnt and fresh fuel regions and at their interface is representative of a large uniform array of burnt and fresh pins in the same moderation conditions. First results are encouraging, showing that the burnt/fresh fuel interface is well represented with a 6 x 6 bundle of burnt pins. The second part of the project involves the use of TSUNAMI, CASMO-4E and DAKOTA to perform parametric and optimization studies on the PROTEUS lattice by varying its pitch (P) and fraction of D{sub 2}O in moderator (F{sub D2O}) to be as representative as possible of a power light water reactor core at hot full power conditions at beginning of cycle (BOC). The parameters P and F{sub D2O} that best represent a PWR at BOC are 1.36 cm and 5% respectively. (authors)

  3. STIMULATION OF FUNDULUS BY HYDROCHLORIC AND FATTY ACIDS IN FRESH WATER, AND BY FATTY ACIDS, MINERAL ACIDS, AND THE SODIUM SALTS OF MINERAL ACIDS IN SEA WATER

    PubMed Central

    Allison, J. B.; Cole, William H.

    1934-01-01

    1. Fundulus heteroclitus was found to be a reliable experimental animal for studies on chemical stimulation in either fresh or sea water. 2. The response of Fundulus to hydrochloric, acetic, propionic, butyric, valeric, and caproic acids was determined in fresh water, while the same acids plus sulfuric and nitric, as well as the sodium salts of the mineral acids, were tested in sea water. 3. Stimulation of Fundulus by hydrochloric acid in fresh water is correlated with the effective hydrogen ion concentration. Stimulation by the n-aliphatic acids in the same environment is correlated with two factors, the effective hydrogen ion concentration and the potential of the non-polar group in the molecule. However, as the number of CH2 groups increases the stimulating effect increases by smaller and smaller amounts, approaching a maximum value. 4. Stimulation of Fundulus by hydrochloric, sulfuric, and nitric acids in sea water is correlated with the forces of primary valence which in turn are correlated with the change in hydrogen ion concentration of the sea water. The n-aliphatic acids increase in stimulating efficiency in sea water as the length of the carbon chain increases, but a limiting value is not reached as soon as in fresh water. 5. Only a slight difference in stimulation by hydrochloric acid is found in sea water and in fresh water. However, there is a significant difference in stimulation by the fatty acids in fresh and in sea water, which is partly explained by the different buffering capacities of the two media. It is to be noted that in the same environment two different fish, Fundulus and Eupomotis, give different results, while the same fish (Fundulus) in two different environments responds similarly to mineral acids but differently to fatty acids. These results illustrate that stimulation is a function of the interaction between environment and receptors, and that each is important in determining the response. 6. Stimulation by sodium chloride, nitrate

  4. Acidic Electrolyzed Water as a Novel Transmitting Medium for High Hydrostatic Pressure Reduction of Bacterial Loads on Shelled Fresh Shrimp

    PubMed Central

    Du, Suping; Zhang, Zhaohuan; Xiao, Lili; Lou, Yang; Pan, Yingjie; Zhao, Yong

    2016-01-01

    Acidic electrolyzed water (AEW), a novel non-thermal sterilization technology, is widely used in the food industry. In this study, we firstly investigated the effect of AEW as a new pressure transmitting medium for high hydrostatic pressure (AEW-HHP) processing on microorganisms inactivation on shelled fresh shrimp. The optimal conditions of AEW-HHP for Vibrio parahaemolyticus inactivation on sterile shelled fresh shrimp were obtained using response surface methodology: NaCl concentration to electrolysis 1.5 g/L, treatment pressure 400 MPa, treatment time 10 min. Under the optimal conditions mentioned above, AEW dramatically enhanced the efficiency of HHP for inactivating V. parahaemolyticus and Listeria monocytogenes on artificially contaminated shelled fresh shrimp, and the log reductions were up to 6.08 and 5.71 log10 CFU/g respectively, while the common HHP could only inactivate the two pathogens up to 4.74 and 4.31 log10 CFU/g respectively. Meanwhile, scanning electron microscopy (SEM) showed the same phenomenon. For the naturally contaminated shelled fresh shrimp, AEW-HHP could also significantly reduce the micro flora when examined using plate count and PCR-DGGE. There were also no significant changes, histologically, in the muscle tissues of shrimps undergoing the AEW-HHP treatment. In summary, using AEW as a new transmitting medium for HHP processing is an innovative non thermal technology for improving the food safety of shrimp and other aquatic products. PMID:27014228

  5. Pathway Analysis and Metabolites Identification by Metabolomics of Etiolation Substrate from Fresh-Cut Chinese Water Chestnut (Eleocharis tuberosa).

    PubMed

    Li, Yi-Xiao; Pan, Yong-Gui; He, Feng-Ping; Yuan, Meng-Qi; Li, Shang-Bin

    2016-12-01

    Fresh-cut Chinese water chestnuts (CWC) turn yellow after being peeled, reducing their shelf life and commercial value. Metabolomics, the systematic study of the full complement of small molecular metabolites, was useful for clarifying the mechanism of fresh-cut CWC etiolation and developing methods to inhibit yellowing. In this study, metabolic alterations associated with etiolation at different growth stages (0 day, 2 days, 3 days, 4 days, 5 days) from fresh-cut CWC were investigated using LC-MS and analyzed by pattern recognition methods (principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and orthogonal projection to latent structures-discriminant analysis (OPLS-DA)). The metabolic pathways of the etiolation molecules were elucidated. The main metabolic pathway appears to be the conversion of phenylalanine to p-coumaroyl-CoA, followed by conversion to naringenin chalcone, to naringenin, and naringenin then following different pathways. Firstly, it can transform into apigenin and its derivatives; secondly, it can produce eriodictyol and its derivatives; and thirdly it can produce dihydrokaempferol, quercetin, and myricetin. The eriodictyol can be further transformed to luteolin, cyanidin, dihydroquercetin, dihydrotricetin, and others. This is the first reported use of metabolomics to study the metabolic pathways of the etiolation of fresh-cut CWC.

  6. Acidic Electrolyzed Water as a Novel Transmitting Medium for High Hydrostatic Pressure Reduction of Bacterial Loads on Shelled Fresh Shrimp.

    PubMed

    Du, Suping; Zhang, Zhaohuan; Xiao, Lili; Lou, Yang; Pan, Yingjie; Zhao, Yong

    2016-01-01

    Acidic electrolyzed water (AEW), a novel non-thermal sterilization technology, is widely used in the food industry. In this study, we firstly investigated the effect of AEW as a new pressure transmitting medium for high hydrostatic pressure (AEW-HHP) processing on microorganisms inactivation on shelled fresh shrimp. The optimal conditions of AEW-HHP for Vibrio parahaemolyticus inactivation on sterile shelled fresh shrimp were obtained using response surface methodology: NaCl concentration to electrolysis 1.5 g/L, treatment pressure 400 MPa, treatment time 10 min. Under the optimal conditions mentioned above, AEW dramatically enhanced the efficiency of HHP for inactivating V. parahaemolyticus and Listeria monocytogenes on artificially contaminated shelled fresh shrimp, and the log reductions were up to 6.08 and 5.71 log10 CFU/g respectively, while the common HHP could only inactivate the two pathogens up to 4.74 and 4.31 log10 CFU/g respectively. Meanwhile, scanning electron microscopy (SEM) showed the same phenomenon. For the naturally contaminated shelled fresh shrimp, AEW-HHP could also significantly reduce the micro flora when examined using plate count and PCR-DGGE. There were also no significant changes, histologically, in the muscle tissues of shrimps undergoing the AEW-HHP treatment. In summary, using AEW as a new transmitting medium for HHP processing is an innovative non thermal technology for improving the food safety of shrimp and other aquatic products.

  7. Quality of fresh-cut 'Kent' mango slices prepared from hot-water or non-hot water-treated fruit

    USDA-ARS?s Scientific Manuscript database

    This study addressed the effects of hot water (HW) quarantine treatment as mandated by the USDA-APHIS, for all mangoes imported to the United States, on the visual and compositional quality factors, aroma volatile production, respiration rate, and electrolyte leakage of fresh-cut 'Kent' mango slices...

  8. Spatial and overwinter changes in clam populations of San Pablo Bay, a semiarid estuary with highly variable freshwater inflow

    USGS Publications Warehouse

    Poulton, V.K.; Lovvorn, J.R.; Takekawa, John Y.

    2004-01-01

    In many estuaries worldwide, climate trends together with human diversion of fresh water have dramatically impacted the benthos. Such impacts have sometimes been complicated by exotic species, whose invasion and persistence can be mediated by wide variations in freshwater inflow. Monitoring such changes usually involves periodic samples at a few sites; but sampling that does not recognize variation at a range of spatial and seasonal scales may not reveal important benthic trends. San Pablo Bay, in northern San Francisco Bay, has extreme fluctuations in freshwater inflow. This bay also experienced a major benthic change with introduction of the Asian clam (Potamocorbula amurensis) in 1986. This species initially displaced the former community, but later appeared to vary in abundance depending on site and freshwater inflow. To investigate such patterns and provide guidelines for research and monitoring, we took 1746 core samples at six sites around San Pablo Bay from 19 October to 17 December 1999 and from 6 March to 19 April 2000. Most biomass consisted of the clams P. amurensis,Macoma balthica and Mya arenaria. Potamocorbula amurensis dominated the benthos at most sites in the fall and recruited a new cohort during winter, while there was weak recruitment in M. balthica and none in M. arenaria. At most but not all sites, densities of P. amurensis and M. arenaria declined dramatically over winter while M. balthica declined only slightly. The dominant clams had patch diameters >5 m at most but not all sites, and some showed inconsistent patch structure at scales of 100–1400 m. In this semiarid estuary with highly variable freshwater inflow, samples for research and monitoring should include multiple sites and seasons, and samples within sites should be ≥5 m apart to account for between-patch variation. Species abundance in winter 1999–2000 appeared to be affected by high freshwater inflows in 1997–1999, while spatial patterns were probably most affected by

  9. The effects of calcitonin on plasma calcium levels and bone metabolism in the fresh water teleost Channa punctatus.

    PubMed

    Mukherjee, Dola; Sen, Utpal; Bhattacharyya, S P; Mukherjee, Dilip

    2004-08-01

    Administration of salmon calcitonin (sCT) caused significant reduction in total and ultrafiltrable plasma calcium content in the plasma of a fresh water female teleost Channa punctatus. A time-bound analysis on the effect of sCT showed a highly significant short duration reduction in total and ultrafiltrable plasma calcium content in fish kept in normal tap water and low-calcium water and a moderate hypocalcemia in fish kept in high-calcium water. Sexually immature adult fish showed a greater response than the sexually mature ones. Using tartrate-resistant acid phosphatase (TRACP) and alkaline phosphatase (ALP) activities in plasma and hydroxyproline (HYP) excretion in urine, the effect of sCT on the inhibition of bone calcium resorption were examined. In both sexually mature and immature adult fish, kept in normal tap water, sCT significantly suppressed TRACP and ALP activities in plasma and excretion of HYP in urine within 2-6 h with a maximum at 4 h after injection. Salmon CT treatment to sexually immature adult fish caused significant increase in skeletal bone calcium concentration. Taken together, all this information indicates that CT in a fresh water female teleost is an effective regulator of plasma calcium levels, and its action, at least in part, operates through inhibition of bone calcium resorption.

  10. Bis(4-chlorophenyl) sulfone (BCPS) in Swedish marine and fresh water wildlife-a screening study.

    PubMed

    Norström, Karin; Olsson, Anders; Olsson, Mats; Bergman, Ake

    2004-07-01

    Bis(4-chlorophenyl) sulfone (BCPS) is a high production volume chemical (HPVC) applied in thermostable polymers. BCPS has been detected as an environmental contaminant both in Europe and in North America but it is still not a commonly studied pollutant. In this study, three Baltic Sea fish species; herring (Clupea harengus), salmon (Salmo salar) and perch (Perca fluviatilis) from the Swedish coast, and one inland fish species, arctic char (Salvelinus alpinus), were analysed to screen for the occurrence and distribution of BCPS. Salmon and arctic char, were sampled in the early 1970s as well as the late 1990s. Fish eating grey seal (Halichoerus gryphus) and guillemot (Uria aalge) from the Baltic Sea were included to screen for whether BCPS biomagnify or not. The representativeness of the analysed samples for studying bioaccumulation of environmental pollutants was compared through analysis of two well known persistent and bioaccumulating compounds, 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), and 4,4'-DDE. Pooled muscle and blubber samples based on 4-10 individuals were used for analysis, as well as individual samples of grey seal blubber. 2,4,4'-Trichlorodiphenyl sulfone, was synthesised and applied as an internal standard. BCPS was detected in all marine samples but in only one of the fresh water fish samples. The highest BCPS concentrations detected, 1600 and 1900 ng/g lipid weighet (l.w.), were found in muscle from Baltic guillemot. The results indicate that BCPS is bioaccumulated in both grey seal and guillemot, and that the guillemot has higher concentrations of BCPS than the grey seal (50-500 ng/g l.w.). The concentrations found in different species of fish from the Baltic Sea ranged between 15-37 ng/g l.w. and lower concentrations were found in freshwater species (n.d.-1.8 ng/g l.w.). The present study shows that BCPS is found in all investigated species of wildlife but, in most species, still at low concentrations. However, the guillemot has levels in the

  11. The Australian fresh water isopod (Phreatoicidea: Isopoda) allows insights into the early mitogenomic evolution of isopods.

    PubMed

    Kilpert, Fabian; Podsiadlowski, Lars

    2010-03-01

    The complete mitochondrial (mt) genome sequence of the Australian fresh water isopod Eophreatoicus sp.-14 has been determined. The new species is a member of the taxon Phreatoicidea, a clade of particular interest, as it is often regarded as the sister group to all other Isopoda. Although the overall genome organization of Eophreatoicus sp.-14 conforms to the typical state of Metazoa--it is a circular ring of DNA hosting the usual 37 genes and one major non-coding region--it bears a number of derived characters that fall within the scope of "genome morphology". Earlier studies have indicated that the isopod mitochondrial gene order is not as conserved as that of other crustaceans. Indeed, the mt genome of Eophreatoicus sp.-14 shows an inversion of seven genes (including cox1), which is as far as we know unique. Even more interesting is the derived arrangement of nad1, trnL(CUN), rrnS, control region, cob, trnT, nad5 and trnF that is shared by nearly all available isopod mt genomes. A striking feature is the close proximity of the rearranged genes to the mt control region. Inferable gene translocation events are, however, more suitable to trace the evolution of mt genomes. Genes like nad1/trnL(CUN) and nad5/trnF, which retained their adjacent position after being rearranged, were most likely translocated together. A very good example for the need to understand the mechanisms of translocations is the remolding of trnL(UUR) to trnL(CUN). Both tRNA genes are adjacent and have a high sequence similarity, probably the result of a gene duplication and subsequent anticodon mutation. Modified secondary structures were found in three tRNAs of Eophreatoicus sp.-14, which are all characterized by the loss of the DHU-arm. This is common to crustaceans for tRNA Serine(AGY), while the arm-loss in tRNA Cysteine within Malacostraca is only shared by other isopods. Modification of the third tRNA, Isoleucine, is not known from any other related species. Nucleotide frequencies of

  12. Management of fresh water weeds (macrophytes) by vermicomposting using Eisenia fetida.

    PubMed

    Najar, Ishtiyaq Ahmed; Khan, Anisa B

    2013-09-01

    In the present study, potential of Eisenia fetida to recycle the different types of fresh water weeds (macrophytes) used as substrate in different reactors (Azolla pinnata reactor, Trapa natans reactor, Ceratophyllum demersum reactor, free-floating macrophytes mixture reactor, and submerged macrophytes mixture reactor) during 2 months experiment is investigated. E. fetida showed significant variation in number and weight among the reactors and during the different fortnights (P <0.05) with maximum in A. pinnata reactor (number 343.3 ± 10.23 %; weight 98.62 ± 4.23 % ) and minimum in submerged macrophytes mixture reactor (number 105 ± 5.77 %; weight 41.07 ± 3.97 % ). ANOVA showed significant variation in cocoon production (F4 = 15.67, P <0.05) and mean body weight (F4 = 13.49, P <0.05) among different reactors whereas growth rate (F3 = 23.62, P <0.05) and relative growth rate (F3 = 4.91, P <0.05) exhibited significant variation during different fortnights. Reactors showed significant variation (P <0.05) in pH, Electrical conductivity (EC), Organic carbon (OC), Organic nitrogen (ON), and C/N ratio during different fortnights with increase in pH, EC, N, and K whereas decrease in OC and C/N ratio. Hierarchical cluster analysis grouped five substrates (weeds) into three clusters-poor vermicompost substrates, moderate vermicompost substrate, and excellent vermicompost substrate. Two principal components (PCs) have been identified by factor analysis with a cumulative variance of 90.43 %. PC1 accounts for 47.17 % of the total variance represents "reproduction factor" and PC2 explaining 43.26 % variance representing "growth factor." Thus, the nature of macrophyte affects the growth and reproduction pattern of E. fetida among the different reactors, further the addition of A. pinnata in other macrophytes reactors can improve their recycling by E. fetida.

  13. Contrasting patterns in genetic diversity following multiple invasions of fresh and brackish waters.

    PubMed

    Kelly, David W; Muirhead, James R; Heath, Daniel D; Macisaac, Hugh J

    2006-10-01

    of the two invading clades were found principally at recently invaded fresh and brackish water sites in Eastern Europe, and were characterized by higher genetic diversity than putative source populations. Further studies are required to determine if these represent novel genotypes. Our results confirm that biological invasions need not result in diminished genetic diversity, particularly if multiple source populations, each with distinctive genetic composition, contribute to the founding populations.

  14. Effect of Water Stress and Storage Time on Anthocyanins and Other Phenolics of Different Genotypes of Fresh Sweet Basil.

    PubMed

    Luna, María C; Bekhradi, Farzaneh; Ferreres, Federico; Jordán, María J; Delshad, Mojtaba; Gil, María I

    2015-10-28

    This study describes the effect of water stress and storage time on the content of anthocyanins and other phenolics in different genotypes of fresh sweet basil (Ocimum basilicum L.). Purple and green Iranian cultivars and a Genovese variety were exposed to a control (100% of the field capacity, FC) and to water stress of mild and severe deficit irrigation treatments (25 and 50 DI corresponding to 75 and 50% FC, respectively). The individual characterization by HPLC-DAD-ESI/MS(n) and the MS fragmentation pathway of anthocyanins are described. A 50% increase in the anthocyanin content was observed in 50 DI after storage. Water stress markedly enhanced the content of phenolic acids after storage in the three genotypes. Water stress can be an efficient way to help the sustainability of water resources, enriching the content of phenolic compounds that may be beneficial to human health.

  15. Lead uptake and lead loss in the fresh water field crab, Barytelphusa guerini, on exposure to organic and inorganic lead

    SciTech Connect

    Tulasi, S.J.; Yasmeen, R.; Reddy, C.P.; Rao, J.V.R.

    1987-07-01

    Lead is a heavy metal which is widely used in paint industry, pigments, dyes, electrical components and electronics, plastic chemicals and in various other things. Since some of the lead salts are soluble in water, lead presents a potential threat to aquatic organisms. Studies dealing with invertebrates include those on mortality, growth and lead uptake in Lymnaea palustris and bioaccumulation of heavy metals in oysters and mussels. Little information exists regarding the effect of lead on the fresh water crustaceans. Hence the present investigation has been undertaken to study the uptake and loss of lead on exposure to subtoxic levels or organic and inorganic lead.

  16. Determination of naturally-occurring actinides and their progeny in fresh water using ICP-MS and batch separation

    SciTech Connect

    Crain, J.S.; Alvarado, J.A.; Kiely, J.T.

    1995-12-01

    The determination of naturally-occurring actinides (including progeny such as {sup 230}Th) in fresh water is of significance in limnology, hydrology, and environmental monitoring. In many instances, these determinations require multiple analyses and a combination of radiometric and elemental measurement techniques (e.g., alpha spectrometry and thermal ionization mass spectrometry). In this work, we will describe the use of a single technique, inductively coupled plasma-mass spectrometry (ICP-MS), for these determinations. We will also describe the batch separation chemistry used to facilitate these determinations in ground and surface water, where natural analyte concentrations run between 1 {mu}g/L and 1 {mu}g/L.

  17. Hot and cold water infusion aroma profiles of Hibiscus sabdariffa: fresh compared with dried.

    PubMed

    Ramírez-Rodrigues, M M; Balaban, M O; Marshall, M R; Rouseff, R L

    2011-03-01

    Calyxes from the Roselle plant (Hibiscus sabdariffa L.) were used to prepare cold (22 °C for 4 h) and hot (98 °C for 16 min) infusions/teas from both fresh and dried forms. Aroma volatiles were extracted using static headspace SPME and analyzed using GC-MS and GC-O with 2 different columns (DB-5 and DB-Wax). Totals of 28, 25, 17, and 16 volatiles were identified using GC-MS in the dried hot extract (DHE), dried cold extract (DCE), fresh hot extract (FHE), and fresh cold extract (FCE) samples, respectively. In terms of total GC-MS peak areas DHE ≫ DCE > FHE ≫ FCE. Nonanal, decanal, octanal, and 1-octen-3-ol were among the major volatiles in all 4 beverage types. Thirteen volatiles were common to all 4 teas. Furfural and 5-methyl furfural were detected only in dried hibiscus beverages whereas linalool and 2-ethyl-1-hexanol were detected only in beverages from fresh hibiscus. In terms of aroma active volatiles, 17, 16, 13, and 10 aroma active volatiles were detected for DHE, DCE, FHE, and FCE samples, respectively. The most intense aroma volatiles were 1-octen-3-one and nonanal with a group of 4 aldehydes and 3 ketones common to all samples. Dried samples contained dramatically higher levels of lipid oxidation products such as hexanal, nonanal, and decanal. In fresh hibiscus extracts, linalool (floral, citrus) and octanal (lemon, citrus) were among the highest intensity aroma compounds but linalool was not detected in any of the dried hibiscus extracts. Hibiscus teas/infusions are one of the highest volume specialty botanical products in international commerce. The beverage is consumed for both sensory pleasure and health attributes and is prepared a number of ways throughout the world. Although color and taste attributes have been examined, little information is known about its aroma volatiles and no other study has compared extractions from both fresh and dried as well as extraction temperature differences. This is also, apparently, the first study to identify

  18. The distribution of submersed aquatic vegetation and water lettuce in the fresh and oligohaline tidal Potomac River, 2007

    USGS Publications Warehouse

    Campbell, Sarah Hunter; Rybicki, Nancy B.; Schenk, Edward R.

    2015-01-01

    Surveys documenting the composition of species of submersed aquatic vegetation (SAV) have been conducted in the Potomac River for decades. These surveys can help managers assess the proportion of native and exotic plants in the river or can be used to determine relationships between native and exotic plants, environmental conditions, and wildlife. SAV coverage increased from 2005 to 2007 throughout the fresh and oligohaline study area. The 2007 survey documented here determined that eleven species of SAV were present. The abundance of the exotic species Hydrilla verticillata (hydrilla) was relatively low, and species diversity was relatively high compared to previous years. The survey also revealed a new population of the invasive, floating aquatic plant Pistia stratiotes (water lettuce). In 2007, water lettuce, the latest exotic aquatic plant to be found in the fresh to oligohaline portion of the Potomac River, was most abundant in Mattawoman Creek, Charles County, Maryland. However, it was not observed in the fresh to oligohaline portion of the Potomac River in the summer of 2008. An understanding of the distribution of SAV species and factors governing the abundance of native and invasive aquatic species is enhanced by long-term surveys.

  19. Prediction of microbial growth in fresh-cut vegetables treated with acidic electrolyzed water during storage under various temperature conditions.

    PubMed

    Koseki, S; Itoh, K

    2001-12-01

    Effects of storage temperature (1, 5, and 10 degrees C) on growth of microbial populations (total aerobic bacteria, coliform bacteria, Bacillus cereus, and psychrotrophic bacteria) on acidic electrolyzed water (AcEW)-treated fresh-cut lettuce and cabbage were determined. A modified Gompertz function was used to describe the kinetics of microbial growth. Growth data were analyzed using regression analysis to generate "best-fit" modified Gompertz equations, which were subsequently used to calculate lag time, exponential growth rate, and generation time. The data indicated that the growth kinetics of each bacterium were dependent on storage temperature, except at 1 degrees C storage. At 1 degrees C storage, no increases were observed in bacterial populations. Treatment of vegetables with AcEW produced a decrease in initial microbial populations. However, subsequent growth rates were higher than on nontreated vegetables. The recovery time required by the reduced microbial population to reach the initial (treated with tap water [TW]) population was also determined in this study, with the recovery time of the microbial population at 10 degrees C being <3 days. The benefits of reducing the initial microbial populations on fresh-cut vegetables were greatly affected by storage temperature. Results from this study could be used to predict microbial quality of fresh-cut lettuce and cabbage throughout their distribution.

  20. Microbial biomass at land water interface and its role in regulating ecosystem properties of a fresh water dry tropical woodland lake.

    PubMed

    Pandey, J

    2008-05-01

    This study was aimed at determining microbial biomass at land water interface and the role it plays in regulating ecosystem properties of a fresh water dry tropical woodland lake. Four microbial variables namely biomass-C (Cmic), fumigated CO2-C, substrate induced respiration (SIR) and basal respiration (BR) were measured in humus samples collected from land water interface over a period of one year Microbial biomass (Cmic) was maximum during February (718 micorg CO2-C g(-1)). Similar was the case of fumigated CO2-C (560 microg CO2-C g(-1) 10 d(-1)), SIR (2900 microg CO2-C g(-1)) and BR (480 microg CO2-C g(-1)). Humus-N appeared maximum (1.60%) during November and phenolics (204 microg g(-1)) during December Gross primary productivity (GPP) was found maximum (3.30 g Cm(-2)d(-1)) during March. Almost similar trend appeared for chlorophyll and phytoplankton density. Variation in microbial biomass at land water interface can be explained by seasonality and the quality of substrate material. Asynchrony in the peaks of microbial variables with phytoplankton pulsation and GPP suggested that the microbial biomass through nutrient mineralization regulates ecosystem functioning of a fresh water woodland lake. This has relevance for evaluating the nature of anthropogenic perturbations and for maintenance of fresh water lakes void of human disturbances.

  1. Variation in Lateral Plate Quality in Threespine Stickleback from Fresh, Brackish and Marine Water: A Micro-Computed Tomography Study

    PubMed Central

    Reseland, Janne E.; Østbye, Kjartan; Haugen, Håvard J.; Vøllestad, Leif A.

    2016-01-01

    Introduction It is important to understand the drivers leading to adaptive phenotypic diversity within and among species. The threespine stickleback (Gasterosteus aculeatus) has become a model system for investigating the genetic and phenotypic responses during repeated colonization of fresh waters from the original marine habitat. During the freshwater colonization process there has been a recurrent and parallel reduction in the number of lateral bone plates, making it a suitable system for studying adaptability and parallel evolution. Objective The aim of this study was to investigate an alternative evolutionary path of lateral plate reduction, where lateral plates are reduced in size rather than number. Materials and Methods A total of 72 threespine stickleback individuals from freshwater (n = 54), brackish water (n = 27) and marine water (n = 9) were analysed using microcomputed tomography (μCT) to determine variation in size, thickness and structure of the lateral plates. Furthermore, whole-body bone volume, and bone volume, bone surface and porosity of lateral plate number 4 were quantified in all specimens from each environment. Results The results showed a significant difference in plate size (area and volume) among populations, where threespine stickleback from polymorphic freshwater and brackish water populations displayed lateral plates reduced in size (area and volume) compared to marine stickleback Conclusions Reduction of lateral plates in threespine stickleback in fresh and brackish water occurs by both plate loss and reduction in plate size (area and volume). PMID:27764140

  2. Leptospira exposure in the human environment in France: A survey in feral rodents and in fresh water.

    PubMed

    Aviat, F; Blanchard, B; Michel, V; Blanchet, B; Branger, C; Hars, J; Mansotte, F; Brasme, L; De Champs, C; Bolut, P; Mondot, P; Faliu, J; Rochereau, S; Kodjo, A; Andre-Fontaine, G

    2009-11-01

    This paper confirms the important role of rodents to be maintenance hosts of leptospires. Their role is related to renal carriage and shedding of leptospires into urine, thus contaminating fresh water. Serological and carriage of feral rodents trapped in France were determined by MAT and hap1PCR specific for pathogenic leptospires. In same areas, fresh water samples were analyzed by hap1PCR. The overall seroprevalence was 44% in 649 rodents and was similar regardless of the species. Seroprevalence for leptospirosis is about 20-53% according to species. hap1PCR (516 kidneys) showed that renal carriage was higher in brown rats (34.7%) and muskrats (15.8%) than in coypus (3.3%). hap1PCR demonstrates a significative difference (P-value > 10(-12)) for the renal carriage between the different species: muskrats and rats are more efficient maintenance hosts than coypu but all infect water. Moreover 5/38 water samples associated with human cases were hap1PCR positive and 1/113 in controlled waters.

  3. Evidence of the particle concentration effect for lead and other metals in fresh waters based on ultraclean technique analyses

    NASA Astrophysics Data System (ADS)

    Benoit, Gaboury

    1995-07-01

    Ultraclean methods were used to produce reliable concentration data for the trace metals Pb, Ag, and Cd in fresh waters and for Ph, Ag, Cu, and Zn in estuarine waters. Partitioning of metals between filter-retained and filtrate fractions exhibited a dependence on total suspended solids (TSS) concentration. This phenomenon, the particle concentration effect (PCE), has been previously documented almost exclusively in marine and estuarine systems and lab simulations, and mainly for radionuclides. The partition coefficient, Kd, was independent of major ion chemistry and pH, supporting the hypothesis that the PCE is caused by metals associated with colloidal particles but counted with the filtrate ("dissolved") fraction. Partition coefficients of the measured metals in fresh waters are predictable across the full range of TSS measured, spanning more than two orders of magnitude. The inferred true partition coefficient for Pb (between solution and particles of all size classes) is greater than 107.4, suggesting that truly dissolved Pb concentrations are extraordinarily low. Previously published data are reinterpreted to show that naturally occurring 210Pb also exhibits the PCE. Freshly precipitated Fe oxyhydroxides partition metals exactly like organic detritus and clays in spite of the great difference in their surface chemistry. The same data rule out the possibility that the PCE could be caused by a decrease in surface area (and surface complexation sites) due to resuspension of larger particles under high TSS conditions. A surprising result is that, while the slope of a log (Kd) - log (TSS) plot for 210Pb is the same as for stable lead, absolute Kd values for 210Pb are uniformly lower by a factor of 4. This suggests that 210Pb and stable lead behave differently from each other in the surface waters studied. One possible explanation is that this dissimilarity may be attributable to differences in speciation that are persistent on a time scale of months, corresponding

  4. Global Anthropogenic Phosphorus Loads to Fresh Water, Grey Water Footprint and Water Pollution Levels: A High-Resolution Global Study

    NASA Astrophysics Data System (ADS)

    Mekonnen, M. M.; Hoekstra, A. Y. Y.

    2014-12-01

    We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.

  5. Precipitation and Runoff Simulations of the Carson Range and Pine Nut Mountains, and Updated Estimates of Ground-Water Inflow and the Ground-Water Budgets for Basin-Fill Aquifers of Carson Valley, Douglas County, Nevada, and Alpine County, California

    USGS Publications Warehouse

    Jeton, Anne E.; Maurer, Douglas K.

    2007-01-01

    Recent estimates of ground-water inflow to the basin-fill aquifers of Carson Valley, Nevada, and California, from the adjacent Carson Range and Pine Nut Mountains ranged from 22,000 to 40,000 acre-feet per year using water-yield and chloride-balance methods. In this study, watershed models were developed for watersheds with perennial streams and for watersheds with ephemeral streams in the Carson Range and Pine Nut Mountains to provide an independent estimate of ground-water inflow. This report documents the development and calibration of the watershed models, presents model results, compares the results with recent estimates of ground-water inflow to the basin-fill aquifers of Carson Valley, and presents updated estimates of the ground-water budget for basin-fill aquifers of Carson Valley. The model used for the study was the Precipitation-Runoff Modeling System, a physically based, distributed-parameter model designed to simulate precipitation and snowmelt runoff as well as snowpack accumulation and snowmelt processes. Geographic Information System software was used to manage spatial data, characterize model drainages, and to develop Hydrologic Response Units. Models were developed for * Two watersheds with gaged perennial streams in the Carson Range and two watersheds with gaged perennial streams in the Pine Nut Mountains using measured daily mean runoff, * Ten watersheds with ungaged perennial streams using estimated daily mean runoff, * Ten watershed with ungaged ephemeral streams in the Carson Range, and * A large area of ephemeral runoff near the Pine Nut Mountains. Models developed for the gaged watersheds were used as index models to guide the calibration of models for ungaged watersheds. Model calibration was constrained by daily mean runoff for 4 gaged watersheds and for 10 ungaged watersheds in the Carson Range estimated in a previous study. The models were further constrained by annual precipitation volumes estimated in a previous study to provide

  6. Taphonomy of deciduous leaves and changes in the d13C signal after deposition in fresh water settings

    NASA Astrophysics Data System (ADS)

    Reimann, Simon; Roth-Nebelsick, Anita; Nebelsick, James; Grein, Michaela

    2016-04-01

    Carbon isotopic signals from fossil plant material are an important source of information for palaeoecology and palaeoclimatology. Usually, the 13C isotope is depleted in plant material, compared to the atmospheric 13C content, because 13C is discriminated against 12C during the process of photosynthesis. The degree of 13C discrimination depends on the photosynthetic pathway (C3, C4 and CAM) and is substantially affected by environmental factors (for example, water stress). Various plant material components, however, differ also with respect to their 13C content. It is generally assumed that the d13C signal found in fossil plants reflects that of the living plant to a sufficient degree. Obtaining information on possible alterations during the taphonomic process is, however, desirable. In this study, changes in d13C of deciduous leaves are monitored, from the living leaf still attached to the tree to leaves deposited in fresh water setting for one or more years, thus focusing on early stages of taphonomy. The considered taxa are species from Quercus (oak) and Fagus (beech). Deposited leaves from three fresh water environments in Southwestern Germany were studied: active stream in a forest, still water pond in a forest, and a waterlogged moor environment. Additionally to the isotope measurements, the degree of leaf tissue degradation and colonization with degrading organisms were observed with Scanning Electron Microscopy.

  7. Monitoring water quality in Toronto's urban stormwater ponds: Assessing participation rates and data quality of water sampling by citizen scientists in the FreshWater Watch.

    PubMed

    Scott, Andrew B; Frost, Paul C

    2017-08-15

    From 2013 to 2015, citizen scientist volunteers in Toronto, Canada were trained to collect and analyze water quality in urban stormwater ponds. This volunteer sampling was part of the research program, FreshWater Watch (FWW), which aimed to standardize urban water sampling efforts from around the globe. We held training sessions for new volunteers twice yearly and trained a total of 111 volunteers. Over the course of project, ~30% of volunteers participated by collecting water quality data after the training session with 124 individual sampling events at 29 unique locations in Toronto, Canada. A few highly engaged volunteers were most active, with 50% of the samples collected by 5% of trainees. Stormwater ponds generally have poor water quality demonstrated by elevated phosphate concentrations (~30μg/L), nitrate (~427μg/L), and turbidity relative to Canadian water quality standards. Compared to other urban waterbodies in the global program, nutrient concentrations in Toronto's urban stormwater ponds were lower, while turbidity was not markedly different. Toronto FWW (FWW-TO) data was comparable to that measured by standard lab analyses and matched results from previous studies of stormwater ponds in Toronto. Combining observational and chemical data acquired by citizen scientists, macrophyte dominated ponds had lower phosphate concentrations while phytoplankton dominated ponds had lower nitrate concentrations, which indicates a potentially important and unstudied role of internal biogeochemical processes on pond nutrient dynamics. This experience in the FWW demonstrates the capabilities and constraints of citizen science when applied to water quality sampling. While analytical limits on in-field analyses produce higher uncertainty in water quality measurements of individual sites, rapid data collection is possible but depends on the motivation and engagement of the group of volunteers. Ongoing efforts in citizen science will thus need to address sampling effort

  8. The Mysidae (Crustacea: Peracarida: Mysida) in fresh and oligohaline waters of the Mediterranean. Taxonomy, biogeography, and bioinvasion.

    PubMed

    Wittmann, Karl J; Ariani, Antonio P; Daneliya, Mikhail

    2016-07-25

    A census of Mysidae yielded a total of twelve species plus two non-nominotypical subspecies found so far in fresh and oligohaline waters of the Mediterranean, all belonging to the subfamily Mysinae. Among the nine species in fresh-waters, three are stenoendemics, namely of a single lake (Diamysis lacustris), of two neighbouring river systems (Paramysis kosswigi) or of karstic cave waters (Troglomysis vjetrenicensis). Four species-T. vjetrenicensis, D. lacustris, D. fluviatilis, and Paramysis adriatica sp. nov. described in this paper-are confined to freshwater tributaries of the Adriatic Sea (NE-Mediterranean). This strengthens previous findings about the outstanding role of the Adriatic basin for the endemic diversity of freshwater Mysidae within the Mediterranean. This is possibly related to alternating marine and freshwater-terrestrial phases during the Pliocene-Pleistocene in this semi-enclosed basin. Based on current knowledge, freshwater populations of D. mesohalobia heterandra are also confined to the Adriatic basin; this taxon, however, shows many more populations in brackish waters of the E-Mediterranean and Marmora basins. Two freshwater species (Limnomysis benedeni, Hemimysis anomala) are wide-range invaders of Ponto-Caspian origin, with recent expansion into fresh and brackish waters of the NW-Mediterranean. A further immigrant to this part of the Mediterranean, Neomysis integer, is of NE-Atlantic origin and occurs only marginally in fresh-water.        Five among the nine species found at least once in fresh-water were also reported in oligohaline conditions, mostly also at even higher salinities. A total of eight species plus two subspecies were recorded in oligohaline waters (S = 0.5-5). Among these, only one oligohalobious stenoendemic, Diamysis hebraica, inhabits streams at the Levantine coast.        In the historical biogeographical context, the current distribution of only one out of nine indigenous species in an- to oligohaline

  9. Prevalence and antimicrobial susceptibility of Arcobacter species in cow milk, water buffalo milk and fresh village cheese.

    PubMed

    Yesilmen, Simten; Vural, Aydin; Erkan, Mehmet Emin; Yildirim, Ibrahim Halil

    2014-10-01

    In this study, the presence of Arcobacter spp. was examined in cow milk (n=50), water buffalo (WB) milk (n=50) and fresh village cheese (n=50) samples. The 16S rDNA-RFLP method was used for the identification of Arcobacter spp. The disc diffusion method was used to investigate the susceptibility of all strains identified to 18 different antimicrobial substances. The most commonly isolated Arcobacter species were found to be Arcobacter butzleri (38.89%), Arcobacter cryaerophilus (22.23%) and Arcobacter skirrowii (11.12%) in cow milk; A. cryaerophilus (33.33%), Arcobacter cibarius (20.83%) and A. butzleri (12.50%) in WB milk; and A. skirrowii (28.57%), A. butzleri (21.43%) and A. cryaerophilus (14.29%) in fresh village cheese. This is the first study to identify the presence of Arcobacter nitrofigilis, Arcobacter cloacae, Arcobacter halophilus, Arcobacter bivalviorum and A. cibarius species in analyzed samples. It was found that all of the A. cryaerophilus (n:16) isolates were resistant to cefoperazone, cloxacillin and penicillin G; all of the A. skirrowii (n:12) and A. butzleri (n:10) isolates were resistant to cefoperazone, tetracycline, ampicillin, erythromycin, cloxacillin and penicillin G. It was concluded that cow milk, WB milk and fresh village cheese samples are an important source of Arcobacter species and pose a risk to public health.

  10. Fresh Kids: the efficacy of a Health Promoting Schools approach to increasing consumption of fruit and water in Australia.

    PubMed

    Laurence, S; Peterken, R; Burns, C

    2007-09-01

    The Fresh Kids programme utilized the Health Promoting Schools (HPSs) framework to design a whole-of-school, multifaceted intervention targeting specific behaviours to promote healthy eating and reduce the risk factors associated with childhood obesity. The aim of the programme was to evaluate the effectiveness of the HPS framework to increase fruit and water consumption among primary school-aged children over a 2-year period. The study design was an interrupted time series. Four primary schools in the inner west of Melbourne, Australia, participated in the programme intervention. Baseline data were collected using a lunch box audit to assess the frequency of children with fresh fruit, water and sweet drinks, either brought from home or selected from canteen lunch orders. The lunch box audit was repeated periodically for up to 2 years following programme implementation to assess the sustainability of dietary changes. Across all participating schools, significant increases between 25 and 50% were observed in the proportion of children bringing fresh fruit. Similarly, all schools recorded increases between 15 and 60% in the proportion of students bringing filled water bottles to school and reductions between 8 and 38% in the proportion of children bringing sweet drinks. These significant changes in dietary patterns were sustained for up to 2 years following programme implementation. Targeting key nutrition behaviours and using the HPS framework is an effective and simple approach which could be readily implemented in similar childhood settings. Effective strategies include facilitating organizational change within the school; integrating curriculum activities; formalizing school policy and establishing project partnerships with local community nutrition and dietetic services.

  11. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, W. J.

    2014-05-01

    Wim J. de Lange, Geert F. Prinsen, Jacco H. Hoogewoud, Ab A Veldhuizen, Joachim Hunink, Erik F.W. Ruijgh, Timo Kroon Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses

  12. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, Wim; Prinsen, Geert.; Hoogewoud, Jacco; Veldhuizen, Ab; Ruijgh, Erik; Kroon, Timo

    2013-04-01

    Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with? by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses. Regional expertise is welcomed in the calibration phase of NHI. It aims to reduce uncertainties by improving the

  13. Efficacy of sanitizers to inactivate Escherichia coli O157:H7 on fresh-cut carrot shreds under simulated process water conditions.

    PubMed

    Gonzalez, Rolando J; Luo, Yaguang; Ruiz-Cruz, Saul; McEvoy, James L

    2004-11-01

    Chlorine is widely used as a sanitizer to maintain the microbial quality and safety of fresh-cut produce; however, chlorine treatment lacks efficacy on pathogen reduction, especially when the fresh-cut processing water contains heavy organic loads. A more efficacious sanitizer that can tolerate the commercial processing conditions is needed to maintain microbial safety of fresh-cut produce. This study evaluated the efficacy of Escherichia coli O157:H7 reduction on fresh-cut carrots using new and traditional sanitizers with tap water and fresh-cut processing water scenarios. Fresh-cut carrot shreds inoculated with E. coli O157:H7 were washed in sanitizer solutions including 200 ppm chlorine, citric acid-based sanitizer (Pro-San), 80 ppm peroxyacetic acid-based sanitizer (Tsunami 100), and 1,000 ppm acidified sodium chlorite (SANOVA) prepared in fresh tap water or simulated processing water with a chemical oxygen demand level of approximately 3,500 mg/liter. Samples were packaged and stored at 5 degrees C. Microbial analyses performed at days 0, 7, and 14 indicate that the organic load in the process water significantly affected the efficacy of chlorine on pathogen removal and was especially evident on samples tested during storage. Acidified sodium chlorite provided a strong pathogen reduction even under process water conditions with up to a 5.25-log reduction when compared with the no-wash control. E. coli O157:H7 was not recovered on acidified sodium chlorite-treated samples during the entire 14 days of storage, even following an enrichment step. These results suggest that acidified sodium chlorite holds considerable promise as an alternative sanitizer of fresh-cut produce.

  14. Characterization and pharmacological potential of Lactobacillus sakei 1I1 isolated from fresh water fish Zacco koreanus.

    PubMed

    Bajpai, Vivek K; Han, Jeong-Ho; Nam, Gyeong-Jun; Majumder, Rajib; Park, Chanseo; Lim, Jeongheui; Paek, Woon Kee; Rather, Irfan A; Park, Yong-Ha

    2016-03-15

    There are still a large variety of microorganisms among aquatic animals which have not been explored for their pharmacological potential. Hence, present study was aimed to isolate and characterize a potent lactic acid bacterium from fresh water fish sample Zacco koreanus, and to confirm its pharmacological potential. Isolation of lactic acid bacteria (LAB) from fresh water fish samples was done using serial dilution method. Biochemical identification and molecular characterization of selected LAB isolate 1I1, based on its potent antimicrobial efficacy, was accomplished using API kit and 16S rRNA gene sequencing analysis. Further, 1I1 was assessed for α-glucosidase and tyrosinase inhibitory potential as well as antiviral efficacy against highly pathogenic human influenza virus H1N1 using MDCK cell line in terms of its pharmacological potential. Here, we first time report isolation as well as biochemical and molecular characterization of a lactic acid bacterium Lactobacillus sakei 1I1 isolated from the intestine of a fresh water fish Z. koreanus. As a result, L. sakei 1I1 exhibited potent antimicrobial effect in vitro, and diameter of zones of inhibition of 1I1 against the tested pathogens was found in the range of 13.32 ± 0.51 to 23.16 ± 0.32 mm. Also L. sakei 1I1 at 100 mg/ml exhibited significant (p < 0.05) α-glucosidase and tyrosinase inhibitory activities by 60.69 and 72.59%, in terms of its anti-diabetic and anti-melanogenic potential, respectively. Moreover, L. sakei 1I1 displayed profound anti-cytopathic effect on MDCK cell line when treated with its ethanol extract (100 mg/ml), confirming its potent anti-viral efficacy against H1N1 influenza virus. These findings reinforce the suggestions that L. sakei 1I1 isolated from the intestine of fresh water fish Z. koreanus might be a candidate of choice for using in pharmacological preparations as an effective drug.

  15. Collection of fission and activation product elements from fresh and ocean waters: a comparison of traditional and novel sorbents

    SciTech Connect

    Johnson, Bryce E.; Santschi, Peter H.; Addleman, Raymond S.; Douglas, Matthew; Davidson, Joseph D.; Fryxell, Glen E.; Schwantes, Jon M.

    2010-04-01

    Monitoring natural waters for the inadvertent release of radioactive fission products produced as a result of nuclear power generation downstream from these facilities is essential for maintaining water quality. To this end, we evaluated sorbents for simultaneous in-situ large volume extraction of radionuclides with both soft (e.g., Ag) and hard metal (e.g., Co, Zr, Nb, Ba, and Cs) or anionic (e.g., Ru, Te, Sb) character. In this study, we evaluated a number of conventional and novel nanoporous sorbents in both fresh and salt waters. In most cases, the nanoporous sorbents demonstrated enhanced retention of analytes. Salinity had significant effects upon sorbent performance and was most significant for hard cations, specifically Cs and Ba. The presence of natural organic matter had little effect on the ability of chemisorbents to extract target elements.

  16. Suspended-sediment and fresh-water discharges in the Ob and Yenisey rivers, 1960-1988

    USGS Publications Warehouse

    Meade, R.H.; Bobrovitskaya, N.N.; Babkin, V.I.

    2000-01-01

    Of the world's great rivers, the Ob and Yenisey rank among the largest suppliers of fresh water and among the smallest suppliers of suspended sediment to the coastal ocean. Sediment in the middle reaches of the rivers is mobilized from bordering terraces and exchanged between channels and flood plains. Sediment in the lower reaches of these great rivers is deposited and stored (permanently, on a millennial time scale) in flood plains. Sediment discharges, already small under natural conditions, are diminished further by large manmade reservoirs that trap significant proportions of the moving solids. The long winter freeze and sudden spring breakup impose a peakedness in seasonal water runoff and sediment discharge that contrasts markedly with that in rivers of the tropics and more temperate climates. Very little sediment from the Ob and Yenisey rivers is being transported to the open waters of the Arctic Ocean under present conditions.

  17. Influence of water stress and storage time on preservation of the fresh volatile profile of three basil genotypes.

    PubMed

    Jordán, María J; Quílez, María; Luna, María C; Bekhradi, Farzaneh; Sotomayor, José A; Sánchez-Gómez, Pedro; Gil, María I

    2017-04-15

    The main goal of the present study was to describe the volatile profile of three different basil genotypes (Genovese and Green and Purple Iranian), and the impact that water stress (75% and 50% field capacity) and storage time (up to 7days) have under mild refrigerated conditions. The chromatographic profile pointed to three different chemotypes: linalool/eugenol, neral/geranial, and estragol, for Genovese, Green, and Purple genotypes, respectively. Water stress depleted the volatile profile of these three landraces, due to a reduction in the absolute concentrations of some of the components related to fresh aroma (linalool, nerol, geraniol and eugenol). The stability of the basil volatile profile during storage varied depending on the water stress that had been applied. Concentration reductions of close to 50% were quantified for most of the components identified in the Purple genotype.

  18. Collection of fission and activation product elements from fresh and ocean waters: a comparison of traditional and novel sorbents.

    PubMed

    Johnson, Bryce E; Santschi, Peter H; Addleman, Raymond Shane; Douglas, Matt; Davidson, Joseph D; Fryxell, Glen E; Schwantes, Jon M

    2011-01-01

    Monitoring natural waters for the inadvertent release of radioactive fission products produced as a result of nuclear power generation downstream from these facilities is essential for maintaining water quality. To this end, we evaluated sorbents for simultaneous in-situ large volume extraction of radionuclides with both soft (e.g., Ag) and hard metal (e.g., Co, Zr, Nb, Ba, and Cs) or anionic (e.g., Ru, Te, Sb) character. In this study, we evaluated a number of conventional and novel nanoporous sorbents in both fresh and salt waters. In most cases, the nanoporous sorbents demonstrated enhanced retention of analytes. Salinity had significant effects upon sorbent performance and was most significant for hard cations, specifically Cs and Ba. The presence of natural organic matter had little effect on the ability of chemisorbents to extract target elements. Copyright © 2010. Published by Elsevier Ltd.

  19. Cold-land Processes Pathfinder Mission (CLPP): Advanced Space-based Observation of Fresh Water Stored in Snow

    NASA Astrophysics Data System (ADS)

    Cline, D.; Davis, R. E.; Yueh, S.

    2005-12-01

    Fresh water stored in snow is an important component of the global water cycle. Across more than half of the Earth's land area, seasonal snowpacks function as dynamic fresh-water reservoirs by storing precipitation and delaying runoff. In many regions snowpacks are the dominant source of runoff, filling rivers and recharging aquifers that over a billion people depend on for their water resources. The importance of snow extends across many facets of science and society. Snow properties influence surface water and energy fluxes and other processes important to weather and climate. Snowpacks influence biogeochemical fluxes, permafrost and frozen soil characteristics, ecosystem dynamics, flooding, and even certain solid-earth hazards and dynamics such as landslides. The economic importance of snow water storage is very large, affecting many sectors of health and commerce. Accelerating shrinkage of seasonal snow packs due to our warming climate threatens water supplies, especially in semi-arid and arid regions where snow is the dominant source of runoff and fresh-water resources are already limited. Moreover, snow is strongly implicated in long-term climate-change hypotheses, which project widespread reduction of snow water storage in the future, affecting freshwater flows with severe adverse effects on biodiversity, regional food security and human health. It is a high priority to determine and understand the extent and causes of changes and variability in snow water storage in order to improve prediction. Advanced snow observations are needed to assess changes in snow water storage and to rigorously test models used to predict future changes. Our conventional ground and airborne snow observing-systems meet many specific local needs, but lack the consistency and coverage necessary for this larger purpose. Current and planned satellites do not have the necessary combination of frequencies and resolutions to measure snow water storage consistently across different

  20. The influence of wellbore inflow on electromagnetic borehole flowmeter measurements

    USGS Publications Warehouse

    Clemo, T.; Barrash, W.; Reboulet, E.C.; Johnson, T.C.; Leven, C.

    2009-01-01

    This paper describes a combined field, laboratory, and numerical study of electromagnetic borehole flowmeter measurements acquired without the use of a packer or skirt to block bypass flow around the flowmeter. The most significant finding is that inflow through the wellbore screen changes the ratio of flow through the flowmeter to wellbore flow. Experiments reveal up to a factor of two differences in this ratio for conditions with and without inflow through the wellbore screen. Standard practice is to assume the ratio is constant. A numerical model has been developed to simulate the effect of inflow on the flowmeter. The model is formulated using momentum conservation within the borehole and around the flowmeter. The model is embedded in the MODFLOW-2000 ground water flow code. ?? 2009 National Ground Water Association.

  1. Application of microbial risk assessment to the development of standards for enteric pathogens in water used to irrigate fresh produce.

    PubMed

    Stine, Scott W; Song, Inhong; Choi, Christopher Y; Gerba, Charles P

    2005-05-01

    Microbial contamination of the surfaces of cantaloupe, iceberg lettuce, and bell peppers via contact with irrigation water was investigated to aid in the development of irrigation water quality standards for enteric bacteria and viruses. Furrow and subsurface drip irrigation methods were evaluated with the use of nonpathogenic surrogates, coliphage PRD1, and Escherichia coli ATCC 25922. The concentrations of hepatitis A virus (HAV) and Salmonella in irrigation water necessary to achieve a 1:10,000 annual risk of infection, the acceptable level of risk used for drinking water by the U.S. Environmental Protection Agency, were calculated with a quantitative microbial risk assessment approach. These calculations were based on the transfer of the selected nonpathogenic surrogates to fresh produce via irrigation water, as well as previously determined preharvest inactivation rates of pathogenic microorganisms on the surfaces of fresh produce. The risk of infection was found to be variable depending on type of crop, irrigation method, and days between last irrigation event and harvest. The worst-case scenario, in which produce is harvested and consumed the day after the last irrigation event and maximum exposure is assumed, indicated that concentrations of 2.5 CFU/100 ml of Salmonella and 2.5 x 10(-5) most probable number per 100 ml of HAV in irrigation water would result in an annual risk of 1:10,000 when the crop was consumed. If 14 days elapsed before harvest, allowing for die-off of the pathogens, the concentrations were increased to 5.7 x 10(3) Salmonella per 100 ml and 9.9 x 10(-3) HAV per 100 ml.

  2. Monitoring dibutyltin and triphenyltin in fresh waters and fish in the United States using micro-liquid chromatography-electrospray/ion trap mass spectrometry.

    PubMed

    Jones-Lepp, T L; Varner, K E; Heggem, D

    2004-01-01

    There is a growing body of evidence that toxic organotins are making their way into terrestrial and aquatic mammals including humans. In the United States, one possible route of environmental exposure to organotins (specifically dibutyltin and triphenyltin) is via fresh surface waters and fish taken from those waters. A unique methodology was used for quantitative and speciation of the organotins. This green-chemistry method combines two extraction techniques (solid-phase extraction for waters; hexane/tropolone extraction for fish) with micro-liquid chromatography-electrospray/ion trap mass spectrometry (micro-LC-ES/ITMS) as the detection method. A small survey looking for organotins in fresh surface waters across the United States, and fish from those waters, was conducted. Various concentrations of dibutyltin and triphenyltin were detected in fresh water, ranging from nondetect to 2 ppb, and nondetect to 6 ppb, respectively. In fish dibutyltin and triphenyltin were detected from nondetect to 200 ppb, and nondetect to 400 ppb, respectively.

  3. DNA-based real-time detection and quantification of aeromonads from fresh water beaches on Lake Ontario.

    PubMed

    Khan, Izhar U H; Loughborough, Alyssa; Edge, Thomas A

    2009-06-01

    The present study was designed to develop a novel, rapid, direct DNA-based protocol to enumerate aeromonads in recreational waters. An Aeromonas genus-specific real-time quantitative polymerase chain reaction (Q-PCR) protocol was developed and optimized using newly designed genus-specific oligonucleotide primers derived from the gyrase B subunit (GyrB) gene. A standard curve was developed based on the PCR protocol with a minimum quantification limit of 10 cell equivalents ml(-1) achieved using an autoclaved water sample from recreational water spiked with known quantities of an Aeromonas ATCC strain. The Q-PCR protocol was validated and applied to detect and quantify the total number of aeromonads in water samples collected from two fresh water beaches on Lake Ontario. The Q-PCR protocol revealed significantly higher numbers of aeromonads in all water samples than a culture-based assay at both beaches. Foreshore sand was found to serve as a reservoir of high concentrations of Aeromonas similar to this phenomenon noted for enteric bacteria like Eschershia coli. The new real-time Q-PCR protocol facilitated the rapid quantification of total numbers of Aeromonas cells present in recreational water samples in <3 hours without culturing.

  4. Replacement of fresh water use by final effluent recovery in a highly optimized 100% recovered paper mill.

    PubMed

    Ordóñez, R; Hermosilla, D; San Pío, I; Blanco, A

    2010-01-01

    A further closure of the water circuit in paper mills with a relative high optimization of their water network is limited by the increase of contamination in the water and runnability problems of the paper machine. Therefore, new strategies for saving water must be focussed on the treatment of final effluents of the paper mill, aiming to obtain high quality water that may replace fresh water use in some applications. An appropriate treatment train performed at pilot scale, consisting on a previous clarification stage followed by anaerobic and aerobic treatments, ultrafiltration, and reverse osmosis, made possible producing the highest water quality from the final effluent of the mill. Anaerobic pre-treatment showed very good performance assisting the aerobic stage on removing organics and sulphates, besides it produced enough biogas for being considered as cost-effective. Permeate recovery depended on the silica content of the paper mill effluent, and it was limited to a 50-60%. The reject of the membranes fully met the legislation requirements imposed to effluents arriving to municipal wastewater treatment plants.

  5. Changes in sperm motility in response to osmolality/Ca2+ in three Indonesian fresh water teleosts: goby (Oxyeleotris marmorata), Java carp (Puntius javanicus), and catfish (Clarias batrachus).

    PubMed

    Morita, Masaya; Okuno, Makoto; Susilo, Endang Sri; Setyo, Bambang Pramono; Martarini, Diptarina; Harnadi, Lilik; Takemura, Akihiro

    2006-03-01

    Sperm of most fresh water teleosts become motile when released into the hypotonic fresh water environment, but the role of osmolality and Ca2+ on sperm motility is not clear. Osmotic pressure and Ca2+ concentrations increase from fresh water to brackish water. Java carp Puntius javanicus and catfish Clarias batrachus live and reproduce only in fresh water. On the other hand, goby Oxyeleotris marmorata can acclimate and reproduce from fresh water to brackish water. In the present study, sperm motility and trajectory were compared among these three Indonesian endemic species. Sperm of Java carp, goby, and catfish begun to move in the hypotonic condition (< 200 mOsm/kg). However, the response to Ca2+ was different among these teleosts. In the presence of Ca2+, Java carp sperm swam in circular paths and immediately become quiescent, suggesting that Java carp sperm motility is activated in hypotonic aquatic environment without Ca2+. Goby sperm swam straightforward in the presence or absence of Ca2+. Percentages of motile sperm increased in 100-200 mOsm/kg but suppressed by removal of Ca2+. Regarding sperm motility and trajectory, no response was found in catfish sperm. These results suggest that a response to Ca2+ is different among sperm of the three species and suited to their habitat.

  6. Ceriodaphnia dubia as a Potential Bio-Indicator for Assessing Acute Aluminum Oxide Nanoparticle Toxicity in Fresh Water Environment

    PubMed Central

    Pakrashi, Sunandan; Dalai, Swayamprava; Humayun, Ahmed; Chakravarty, Sujay; Chandrasekaran, Natarajan; Mukherjee, Amitava

    2013-01-01

    Growing nanomaterials based consumer applications have raised concerns about their potential release into the aquatic ecosystems and the consequent toxicological impacts. So environmental monitoring of the nanomaterials in aqueous systems becomes imperative. The current study reveals the potential of Ceriodaphnia dubia (C. dubia) as a bio-indicator for aluminum oxide nanoparticles in a fresh water aquatic ecosystem where it occupies an important ecological niche as a primary consumer. This study aims to investigate the aluminium oxide nanoparticle induced acute toxicity on Ceriodaphnia dubia in a freshwater system. The bioavailability of the aluminum oxide nanoparticles has been studied with respect to their aggregation behavior in the system and correlated with the toxicity endpoints. The oxidative stress generated by the particles contributed greatly toward their toxicity. The crucial role of leached aluminium ion mediated toxicity in the later phases (48 h and 72 h) in conjunction with the effects from the nano-sized particles in the initial phases (24 h) puts forth the dynamics of nanotoxicity in the test system. The internalization of nanoparticles (both gross and systemic uptake) as substantiated through the transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectral (ICP-OES) analysis was another major contributor toward acute toxicity. Concluding the present study, Ceriodaphnia dubia can be a promising candidate for bio-monitoring the aluminium oxide nanoparticles in a fresh water system. PMID:24040143

  7. Impact of fresh and saline water flooding on leaf gas exchange in two Italian provenances of Tamarix africana Poiret.

    PubMed

    Abou Jaoudé, R; de Dato, G; Palmegiani, M; De Angelis, P

    2013-01-01

    In Mediterranean coastal areas, changes in precipitation patterns and seawater levels are leading to increased frequency of flooding and to salinization of estuaries and freshwater systems. Tamarix spp. are often the only woody species growing in such environments. These species are known for their tolerance to moderate salinity; however, contrasting information exists regarding their tolerance to flooding, and the combination of the two stresses has never been studied in Tamarix spp. Here, we analyse the photosynthetic responses of T. africana Poiret to temporary flooding (45 days) with fresh or saline water (200 mm) in two Italian provenances (Simeto and Baratz). The measurements were conducted before and after the onset of flooding, to test the possible cumulative effects of the treatments and effects on twig aging, and to analyse the responses of twigs formed during the experimental period. Full tolerance was evident in T. africana with respect to flooding with fresh water, which did not affect photosynthetic performances in either provenance. Saline flooding was differently tolerated by the two provenances. Moreover, salinity tolerance differently affected the two twig generations. In particular, a reduction in net assimilation rate (-48.8%) was only observed in Baratz twigs formed during the experimental period, compared to pre-existing twigs. This reduction was a consequence of non-stomatal limitations (maximum carboxylation rate and electron transport), probably as a result of higher Na transport to the twigs, coupled with reduced Na storage in the roots.

  8. Ceriodaphnia dubia as a potential bio-indicator for assessing acute aluminum oxide nanoparticle toxicity in fresh water environment.

    PubMed

    Pakrashi, Sunandan; Dalai, Swayamprava; Humayun, Ahmed; Chakravarty, Sujay; Chandrasekaran, Natarajan; Mukherjee, Amitava

    2013-01-01

    Growing nanomaterials based consumer applications have raised concerns about their potential release into the aquatic ecosystems and the consequent toxicological impacts. So environmental monitoring of the nanomaterials in aqueous systems becomes imperative. The current study reveals the potential of Ceriodaphnia dubia (C. dubia) as a bio-indicator for aluminum oxide nanoparticles in a fresh water aquatic ecosystem where it occupies an important ecological niche as a primary consumer. This study aims to investigate the aluminium oxide nanoparticle induced acute toxicity on Ceriodaphnia dubia in a freshwater system. The bioavailability of the aluminum oxide nanoparticles has been studied with respect to their aggregation behavior in the system and correlated with the toxicity endpoints. The oxidative stress generated by the particles contributed greatly toward their toxicity. The crucial role of leached aluminium ion mediated toxicity in the later phases (48 h and 72 h) in conjunction with the effects from the nano-sized particles in the initial phases (24 h) puts forth the dynamics of nanotoxicity in the test system. The internalization of nanoparticles (both gross and systemic uptake) as substantiated through the transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectral (ICP-OES) analysis was another major contributor toward acute toxicity. Concluding the present study, Ceriodaphnia dubia can be a promising candidate for bio-monitoring the aluminium oxide nanoparticles in a fresh water system.

  9. A comparative study on biologically and chemically synthesized silver nanoparticles induced Heat Shock Proteins on fresh water fish Oreochromis niloticus.

    PubMed

    Girilal, M; Krishnakumar, V; Poornima, Paramasivan; Mohammed Fayaz, A; Kalaichelvan, P T

    2015-11-01

    The wide applicability of silver nanoparticles in medicine and pharmaceutical industries leads to its over exploitation and thus contaminating our environment. Majority of these nanoscale dimension particles finally accumulates in fresh water and marine ecosystem. As the nanoparticles behave entirely different from its corresponding bulk material, a better understanding of their environmental impacts in aquatic ecosystems is inevitable. The study was focused on a comparative stress physiology analysis of chemically synthesized silver nanoparticles and biogenic silver nanoparticles. Half maximal inhibitory concentration of biologically synthesized and chemically synthesized nanoparticles was found out (30μg/mL and 20μg/mL respectively). The Heat Shock Protein (HSP70) secretion was analysed in the fresh water fish Oreochromis niloticus after exposing to different concentrations of biologically and chemically synthesized silver nanoparticles along with the silver in its ionic form. The intense immune-histochemical staining of fish tissues (muscle, kidney and liver) analyzed proportionately reflected the stress created. The colour intensity was directly proportional to the stress created or the stress protein released. High level of HSP70 expression was observed in all of the fish tissues exposed to silver ions and chemically synthesized silver nanoparticles, when compared to that of biologically synthesized. The results revealed the significance of comparatively safe and less toxic biogenic nanoparticles compared to the chemically synthesized. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Effect of calcium chloride, zinc chloride, and water infusion on metmyoglobin reducing activity and fresh lamb color.

    PubMed

    Bekhit, A E D; Ilian, M A; Morton, J D; Vanhanan, L; Sedcole, J R; Bickerstaffe, R

    2005-09-01

    Calcium chloride (CaCl2), zinc chloride (ZnCl2), or water infusions were used to investigate the biochemical factors that affect fresh lamb color, and to examine the role of metmyoglobin-reducing activity in regulating this important quality attribute. Immediately after exsanguination, lamb carcasses (n = 6 per treatment) were infused (10% of BW) with 0.3 M CaCl2, 0.05 M ZnCl2, or water via a catheter inserted into the left carotid artery. The right LM was excised at 24-h postmortem and divided into two halves. The caudal portion was cut into 2.5-cm-thick chops and displayed for 6 d under 1,076 lx of white fluorescent lighting at 2 degrees C, whereas the cranial half was vacuum-packaged and stored at 2 degrees C for 3 wk before retail display. Objective color measurements and samples for biochemical analysis were taken at 0, 1, 3, and 6 d of display. In infused carcasses, pH decline was more rapid (P < 0.05) than in untreated controls, and it was greatest for CaCl2-infused carcasses. Calcium chloride-infused carcasses had lower (P < 0.01) NAD and higher (P < 0.001) NADPH concentrations than water- and ZnCl2-infused or untreated control carcasses. The negative effects of calcium infusion on fresh lamb color, higher (P < 0.01) metmyoglobin accumulation rate, and lower (P < 0.01) L*, a*, and b* color measurements could be explained by the lower amounts of unbound water (P < 0.01), shorter sarcomere length (P < 0.01), lower NAD concentrations (P < 0.01), and higher lipid peroxidation (P < 0.01). Zinc and water-infusions produced less (P < 0.01) lipid oxidation and improved the color and color stability of fresh lamb (P < 0.001). Rate of lipid oxidation in LM chops was greater (P < 0.01) after 3 wk of vacuum-packaged storage than 24-h postmortem. Metmyoglobin-reducing activities (sarcoplasmic and myofibrillar) were decreased in response to infusion treatments (P < 0.001), and ZnCl2 infusion resulted in the lowest metmyoglobin-reducing activities (P < 0.001). A

  11. Uptake of uranium by aquatic plants growing in fresh water ecosystem around uranium mill tailings pond at Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K

    2016-01-01

    Concentration of uranium was determined in aquatic plants and substrate (sediment or water) of fresh water ecosystem on and around uranium mill tailings pond at Jaduguda, India. Aquatic plant/substrate concentration ratios (CRs) of uranium were estimated for different sites on and around the uranium mill tailings disposal area. These sites include upstream and downstream side of surface water sources carrying the treated tailings effluent, a small pond inside tailings disposal area and residual water of this area. Three types of plant groups were investigated namely algae (filamentous and non-filamentous), other free floating & water submerged and sediment rooted plants. Wide variability in concentration ratio was observed for different groups of plants studied. The filamentous algae uranium concentration was significantly correlated with that of water (r=0.86, p<0.003). For sediment rooted plants significant correlation was found between uranium concentration in plant and the substrate (r=0.88, p<0.001). Both for other free floating species and sediment rooted plants, uranium concentration was significantly correlated with Mn, Fe, and Ni concentration of plants (p<0.01). Filamentous algae, Jussiaea and Pistia owing to their high bioproductivity, biomass, uranium accumulation and concentration ratio can be useful for prospecting phytoremediation of stream carrying treated or untreated uranium mill tailings effluent. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Surface and textural heterogeneity of fresh hydrous ferric oxides in water and in the dry state

    SciTech Connect

    Bottero, J.Y.; Arnaud, M.; Villieras, F.; Michot, L.J.; Donato, P.; Francois, M. . Groupe de Recherche sur l'Eau et les Solides Divises)

    1993-08-01

    Fresh hydrous ferric oxides (HFO) are formed by precipitation of Fe[sup 3+] solution or ferric polycations initially formed at very acidic pH at different neutralization ratios n = 2 and 2.5 at pH 6.5 the precipitates are particles with a positive surface charge. The IEP and the surface charge measured in NaCl electrolyte vary with n. But in all cases IEP or ZPSE are lower than 8.3. The adsorption of sodium dodecane sulfonate molecules at 20 C allows us to compare the different samples formed by precipitation from n = 0, n = 2, and n = 2.5 solutions and named' n = 0, n = 2, and n = 2.5. Using the two-dimensional adsorption on heterogeneous surfaces theory of Case's group, it is possible to compare the different solids relatively to the affinity of surfactants for the surfaces.

  13. Losses in radial inflow turbines

    NASA Technical Reports Server (NTRS)

    Khalil, I. M.; Tabakoff, W.; Hamed, A.

    1976-01-01

    A study was conducted to determine experimentally and theoretically the losses in radial inflow turbine nozzles. Extensive experimental data was obtained to investigate the flow behavior in a full-scale radial turbine stator annulus. A theoretical model to predict the losses in both the vaned and vaneless regions of the nozzle was developed. In this analysis, the interaction effects between the stator and the rotor are not considered. It was found that the losses incurred due to the end wall boundary layers can be significant, especially if they are characterized by a strong crossflow. The losses estimated using the analytical study are compared with the experimentally determined values.

  14. Variations of DOM quality in inflows of a drinking water reservoir: linking of van Krevelen diagrams with EEMF spectra by rank correlation.

    PubMed

    Herzsprung, Peter; von Tümpling, Wolf; Hertkorn, Norbert; Harir, Mourad; Büttner, Olaf; Bravidor, Jenny; Friese, Kurt; Schmitt-Kopplin, Philippe

    2012-05-15

    Elevated concentrations of dissolved organic matter (DOM) such as humic substances in raw water pose significant challenges during the processing of the commercial drinking water supplies. This is a relevant issue in Saxony, Central East Germany, and many other regions worldwide, where drinking water is produced from raw waters with noticeable presence of chromophoric DOM (CDOM), which is assumed to originate from forested watersheds in spring regions of the catchment area. For improved comprehension of DOM molecular composition, the seasonal and spatial variations of humic-like fluorescence and elemental formulas in the catchment area of the Muldenberg reservoir were recorded by excitation emission matrix fluorescence (EEMF) and ultrahigh-resolution mass spectrometry (FT-ICR-MS). The Spearman rank correlation was applied to link the EEMF intensities with exact molecular formulas and their corresponding relative mass peak abundances. Thereby, humic-like fluorescence could be allocated to the pool of oxygen-rich and relatively unsaturated components with stoichiometries similar to those of tannic acids, which are suspected to have a comparatively high disinfection byproduct formation potential associated with the chlorination