WorldWideScience

Sample records for prepared water-table maps

  1. Mapping water table depth using geophysical and environmental variables.

    Science.gov (United States)

    Buchanan, S; Triantafilis, J

    2009-01-01

    Despite its importance, accurate representation of the spatial distribution of water table depth remains one of the greatest deficiencies in many hydrological investigations. Historically, both inverse distance weighting (IDW) and ordinary kriging (OK) have been used to interpolate depths. These methods, however, have major limitations: namely they require large numbers of measurements to represent the spatial variability of water table depth and they do not represent the variation between measurement points. We address this issue by assessing the benefits of using stepwise multiple linear regression (MLR) with three different ancillary data sets to predict the water table depth at 100-m intervals. The ancillary data sets used are Electromagnetic (EM34 and EM38), gamma radiometric: potassium (K), uranium (eU), thorium (eTh), total count (TC), and morphometric data. Results show that MLR offers significant precision and accuracy benefits over OK and IDW. Inclusion of the morphometric data set yielded the greatest (16%) improvement in prediction accuracy compared with IDW, followed by the electromagnetic data set (5%). Use of the gamma radiometric data set showed no improvement. The greatest improvement, however, resulted when all data sets were combined (37% increase in prediction accuracy over IDW). Significantly, however, the use of MLR also allows for prediction in variations in water table depth between measurement points, which is crucial for land management.

  2. Geostatistical investigations for suitable mapping of the water table: the Bordeaux case (France)

    Science.gov (United States)

    Guekie simo, Aubin Thibaut; Marache, Antoine; Lastennet, Roland; Breysse, Denys

    2016-02-01

    Methodologies have been developed to establish realistic water-table maps using geostatistical methods: ordinary kriging (OK), cokriging (CoK), collocated cokriging (CoCoK), and kriging with external drift (KED). In fact, in a hilly terrain, when piezometric data are sparsely distributed over large areas, the water-table maps obtained by these methods provide exact water levels at monitoring wells but fail to represent the groundwater flow system, manifested through an interpolated water table above the topography. A methodology is developed in order to rebuild water-table maps for urban areas at the city scale. The interpolation methodology is presented and applied in a case study where water levels are monitored at a set of 47 points for a part urban domain covering 25.6 km2 close to Bordeaux city, France. To select the best method, a geographic information system was used to visualize surfaces reconstructed with each method. A cross-validation was carried out to evaluate the predictive performances of each kriging method. KED proves to be the most accurate and yields a better description of the local fluctuations induced by the topography (natural occurrence of ridges and valleys).

  3. Preparation of testate amoebae samples affects water table depth reconstructions in peatland palaeoecological studies

    Directory of Open Access Journals (Sweden)

    Eve Avel

    2013-05-01

    Full Text Available In peatland palaeoecological studies, the preparation of peat samples for testate amoebae (TA analysis involves boiling of samples and microsieving them through a 15-μm sieve. We studied the effect of these preparation stages on the estimation of TA assemblages and on the reconstruction of water table depths (WTD. Our results indicate that the TA assemblages of boiled and unboiled samples are not significantly different, while microsieving reduces the concentration of small TA taxa and results in significantly different TA assemblages. The differences between microsieved and unsieved TA assemblages were reflected also in predicted values of WTD, which indicated drier conditions in case of unsieved samples than in microsieved samples. We conclude that the boiling of samples might be omitted if TA are extracted from the fresh peat samples. Microsieving may lead to erroneous palaeoecological WTD reconstructions and should be avoided if small TA taxa are present in samples.

  4. The feasibility of thermal inertia mapping for detection of perched water tables in semi-arid irrigated lands

    Science.gov (United States)

    Ezra, C. E.; Estes, J. E.; Bonn, F.

    1982-01-01

    The thermal inertia mapping remote sensing technique is evaluated as a potential method for delineating areas of shallow perched water tables and related salinization problems on a regional basis. This method for detecting shallow water tables is based on the existence of significant differences in soil thermal properties between wet and dry soil profiles. Ground observations were conducted at two different test sites in California along the flight line, with one site located in a perched water table area and the other site in a well drained area. Measurements were taken hourly during a four day period (two days before and two days after the flight) for variables such as radiometric, meteorologic, soil moisture and temperature profiles, and surface characteristics. Results indicate that it is not feasible using present apparent thermal inertia remote sensing techniques to reliably delineate regional patterns of very shallow water tables due to the complex environmental system. However, some features within specific fields which may be directly related to the local presence of shallow water tables, such as differences in evaporative cooling due to soil moisture effects between and within fields, can be detected using the thermal inertia technique.

  5. State-wide space-time water table mapping: cautionary tales, tribulations and resolution

    Science.gov (United States)

    Peterson, T. J.; Cheng, X.; Carrara, E.; Western, A. W.; Costelloe, J. F.; Frost, A. J.; McAuley, C. V.

    2015-12-01

    Historically, insufficient quantitative value has been derived from state groundwater monitoring networks. Water level data are occasionally used for calibrating local scale groundwater models and for graphical analysis, but very rarely are they used to identify regional groundwater processes and quantify changes in groundwater dynamics over time. Potentiometric maps have occasionally been derived to assist understanding of regional processes but generally they are derived for one point in time, often simply using an average water level over a year or season. Consequently, dynamics of regional groundwater over time has been compromised. Kriging with external drift (KED) has been a widely adopted approach for regional scale potentiometric mapping in recent years. However, it has a number of unacknowledged fundamental weaknesses - specifically, excessive noise in the head, sensitivity to observation errors and questionable estimation in upland regions and in coastal regions dominated by radial flow. These weaknesses are illustrated and then a multivariate localised colocated cokriging approach is proposed that locally reduces the excessive noise from KED and incorporates the coast line and streams into the estimation. Combined with the temporal interpolation of groundwater head (Peterson & Western, 2014), the approach allows regional scale mapping for a single point in time. To illustrate the approach, the monthly water table level was mapped across Victoria, Australia, from 1985 to 2014. Using the maps, the location and the nature/magnitude of major changes in groundwater dynamics were identified and the surface-groundwater connectivity of major rivers was estimated over time. While geological knowledge can be incorporated, this approach allows data-driven insights to be derived from groundwater monitoring networks without the usual assumptions required for numerical groundwater modeling. Peterson, T. J., and A. W. Western (2014), Nonlinear time-series modeling of

  6. Evaluating the value of ENVISAT ASAR Data for the mapping and monitoring of peatland water table depths

    Science.gov (United States)

    Bechtold, Michel; Schlaffer, Stefan

    2015-04-01

    The Advanced Synthetic Aperture Radar (ASAR) onboard ENVISAT collected C-Band microwave backscatter data from 2005 to 2012. Backscatter in the C-Band depends to a large degree on the roughness and the moisture status of vegetation and soil surface with a penetration depth of ca. 3 cm. In wetlands with stable high water levels, the annual soil surface moisture dynamics are very distinct compared to the surrounding areas, which allows the monitoring of such environments with ASAR data (Reschke et al. 2012). Also in drained peatlands, moisture status of vegetation and soil surface strongly depends on water table depth due to high hydraulic conductivities of many peat soils in the low suction range (Dettmann et al. 2014). We hypothesize that this allows the characterization of water table depths with ASAR data. Here we analyze whether ASAR data can be used for the spatial and temporal estimation of water table depths in different peatlands (natural, near-natural, agriculturally-used and rewetted). Mapping and monitoring of water table depths is of crucial importance, e.g. for upscaling greenhouse gas emissions and evaluating the success of peatland rewetting projects. Here, ASAR data is analyzed with a new map of water table depths for the organic soils in Germany (Bechtold et al. 2014) as well as with a comprehensive data set of monitored peatland water levels from 1100 dip wells and 54 peatlands. ASAR time series from the years 2005-2012 with irregular temporal sampling intervals of 3-14 days were processed. Areas covered by snow were masked. Primary results about the accuracy of spatial estimates show significant correlations between long-term backscatter statistics and spatially-averaged water table depths extracted from the map at the resolution of the ASAR data. Backscatter also correlates with long-term averages of point-scale water table depth data of the monitoring wells. For the latter, correlation is highest between the dry reference backscatter values and

  7. Inferring the heterogeneity, transmissivity and hydraulic conductivity of crystalline aquifers from a detailed water-table map

    Science.gov (United States)

    Dewandel, Benoît; Jeanpert, Julie; Ladouche, Bernard; Join, Jean-Lambert; Maréchal, Jean-Christophe

    2017-07-01

    Estimating the transmissivity or hydraulic conductivity field to characterize the heterogeneity of a crystalline aquifer is particularly difficult because of the wide variations of the parameters. We developed a new approach based on the analysis of a dense network of water-table data. It is based on the concept that large-scale variations in hydraulic head may give information on large-scale aquifer parameters. The method assumes that flux into the aquifer is mainly sub-horizontal and that the water table is mostly controlled by topography, rather than recharge. It is based on an empirical statistical relationship between field data on transmissivity and the inverse slope values of a topography-reduced water-table map. This relationship is used to compute a transmissivity map that must be validated with field measurements. The proposed approach can provide a general pattern of transmissivity, or hydraulic conductivity, but cannot correctly reproduce strong variations at very local scale (less than10 m), and will face of some uncertainties where vertical flows cannot be neglected. The method was tested on a peridotite (ultramafic rock) aquifer of 3.5 km2 in area located in New Caledonia. The resulting map shows transmissivity variations over about 5 orders of magnitude (average LogT: -5.2 ± 0.7). Comparison with a map based on measured water-level data (n = 475) shows that the comparison between LogT-computed values and LogT data deduced from 28 hydraulic tests is estimated with an error less than 20% in 71% of cases (LogT ± 0.4), and with an error less than 10% (LogT ± 0.2 on average) in 39% of cases. From this map a hydraulic-conductivity map has been computed showing values ranging over 8 orders of magnitude. The repeatability of the approach was tested on a second data set of hydraulic-head measurements (n = 543); the mean deviation between both LogT maps is about 11%. These encouraging results show that the method can give valuable parameter estimates, and

  8. Sand and Water Table Play

    Science.gov (United States)

    Wallace, Ann H.; White, Mary J.; Stone, Ryan

    2010-01-01

    The authors observed preschoolers engaged at the sand and water table to determine if math could be found within their play. Wanting to understand how children interact with provided materials and what kinds of math ideas they explore during these interactions, the authors offer practical examples of how such play can promote mathematical…

  9. Sand and Water Table Play

    Science.gov (United States)

    Wallace, Ann H.; White, Mary J.; Stone, Ryan

    2010-01-01

    The authors observed preschoolers engaged at the sand and water table to determine if math could be found within their play. Wanting to understand how children interact with provided materials and what kinds of math ideas they explore during these interactions, the authors offer practical examples of how such play can promote mathematical…

  10. Water-table contours of Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of water-table contours for Nevada. These data were created as part of an effort to provide statewide information on water table and depth to...

  11. Water-Table Levels and Gradients, Nevada, 1947-2004

    Science.gov (United States)

    Lopes, Thomas J.; Buto, Susan G.; Smith, J. LaRue; Welborn, Toby L.

    2006-01-01

    In 1999, the U.S. Environmental Protection Agency began a program to protect the quality of ground water in areas other than ground-water protection areas. These other sensitive ground water areas (OSGWA) are areas that are not currently, but could eventually be, used as a source of drinking water. The OSGWA program specifically addresses existing wells that are used for underground injection of motor-vehicle waste. To help determine whether a well is in an OSGWA, the Nevada Division of Environmental Protection needs statewide information on depth to water and the water table, which partly control the susceptibility of ground water to contamination and contaminant transport. This report describes a study that used available maps and data to create statewide maps of water-table and depth-to-water contours and surfaces, assessed temporal changes in water-table levels, and characterized water-table gradients in selected areas of Nevada. A literature search of published water-table and depth-to-water contours produced maps of varying detail and scope in 104 reports published from 1948 to 2004. Where multiple maps covered the same area, criteria were used to select the most recent, detailed maps that covered the largest area and had plotted control points. These selection criteria resulted in water-table and depth-to-water contours that are based on data collected from 1947 to 2004 being selected from 39 reports. If not already available digitally, contours and control points were digitized from selected maps, entered into a geographic information system, and combined to make a statewide map of water-table contours. Water-table surfaces were made by using inverse distance weighting to estimate the water table between contours and then gridding the estimates. Depth-to-water surfaces were made by subtracting the water-table altitude from the land-surface altitude. Water-table and depth-to-water surfaces were made for only 21 percent of Nevada because of a lack of

  12. Efficient water table evolution discretization using domain transformation

    DEFF Research Database (Denmark)

    Boon, W. M.; Balbarini, Nicola; Binning, Philip John

    2017-01-01

    Domain transformation methods are useful techniques for solving problems on non-stationary domains. In this work, we consider the evolution of the water table in an unconfined aquifer. This nonlinear, time-dependent problem is greatly simplified by using a mapping from the physical domain to a re...... to a reference domain and is then further reduced to a single, (nonlinear) partial differential equation. We show well-posedness of the approach and propose a stable and convergent discretization scheme. Numerical results are presented supporting the theory.......Domain transformation methods are useful techniques for solving problems on non-stationary domains. In this work, we consider the evolution of the water table in an unconfined aquifer. This nonlinear, time-dependent problem is greatly simplified by using a mapping from the physical domain...

  13. Water table fluctuation and its effects on vegetation in a semiarid environment

    Directory of Open Access Journals (Sweden)

    L. Duan

    2011-04-01

    Full Text Available A good understanding of water table fluctuation effects on vegetation is crucial for sustaining fragile hydrology and ecology of semiarid areas such as the Horqin Sandy Land (HSL in northern China, but such understanding is not well documented in literature. The objectives of this study were to examine spatio-temporal variations of water table and their effects on vegetation in a semiarid environment. A 9.71 km2 area within the HSL was chosen and well-instrumented to continuously measure hydrometeorologic parameters (e.g., water table. The area comprises of meadow lands and sandy dunes as well as transitional zones in between. In addition to those measured data, this study also used Landsat TM and MODIS imageries and meteorological data at a station near the study area. The spatio-temporal variations were examined using visual plots and contour maps, while the effects on vegetation were determined by overlaying a water table depth map with a vegetation index map derived from the MODIS imageries. The results indicated that water table was mainly dependent on local topography, localized geological settings, and human activities (e.g., reclamation. At annual and monthly scales, water table was mainly a function of precipitation and potential evapotranspiration. A region within the study area where depth to water table was smaller tended to have better (i.e., more dense and productive vegetation cover. Further, the results revealed that water table fluctuation was more sensitive for vegetations in the meadow lands than in the transitional zones, but it was least sensitive for vegetations in the sandy dunes.

  14. Water table fluctuation and its effects on vegetation in a semiarid environment

    Science.gov (United States)

    Duan, L.; Liu, T.; Wang, X.; Luo, Y.; Wang, W.; Liu, X.

    2011-04-01

    A good understanding of water table fluctuation effects on vegetation is crucial for sustaining fragile hydrology and ecology of semiarid areas such as the Horqin Sandy Land (HSL) in northern China, but such understanding is not well documented in literature. The objectives of this study were to examine spatio-temporal variations of water table and their effects on vegetation in a semiarid environment. A 9.71 km2 area within the HSL was chosen and well-instrumented to continuously measure hydrometeorologic parameters (e.g., water table). The area comprises of meadow lands and sandy dunes as well as transitional zones in between. In addition to those measured data, this study also used Landsat TM and MODIS imageries and meteorological data at a station near the study area. The spatio-temporal variations were examined using visual plots and contour maps, while the effects on vegetation were determined by overlaying a water table depth map with a vegetation index map derived from the MODIS imageries. The results indicated that water table was mainly dependent on local topography, localized geological settings, and human activities (e.g., reclamation). At annual and monthly scales, water table was mainly a function of precipitation and potential evapotranspiration. A region within the study area where depth to water table was smaller tended to have better (i.e., more dense and productive) vegetation cover. Further, the results revealed that water table fluctuation was more sensitive for vegetations in the meadow lands than in the transitional zones, but it was least sensitive for vegetations in the sandy dunes.

  15. Water-table altitude of Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This is a raster-based, depth to ground-water data set for the State of Nevada. The source of this data set is a statewide water-table contour data set constructed...

  16. Revised water table elevations and depths for 1978 and 1979, Closed Basin Division, San Luis Vallet Project, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Memorandum with revised contour map overlays for the highest and lowest elevations and deepest and shallowest depths of the water table in 1978 and 1979 for the...

  17. Malheur NWR: Initial Survey Instructions for Water Table Depth Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Water table wells assist in filling a critical information gap related to fluctuating water table depth and its influence on habitat expression within wet meadow...

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

    Directory of Open Access Journals (Sweden)

    S. W. Lyon

    2006-01-01

    Full Text Available Shallow water tables near-streams often lead to saturated, overland flow generating areas in catchments in humid climates. While these saturated areas are assumed to be principal biogeochemical hot-spots and important for issues such as non-point pollution sources, the spatial and temporal behavior of shallow water tables, and associated saturated areas, is not completely understood. This study demonstrates how geostatistical methods can be used to characterize the spatial and temporal variation of the shallow water table for the near-stream region. Event-based and seasonal changes in the spatial structure of the shallow water table, which influences the spatial pattern of surface saturation and related runoff generation, can be identified and used in conjunction to characterize the hydrology of an area. This is accomplished through semivariogram analysis and indicator kriging to produce maps combining soft data (i.e., proxy information to the variable of interest representing general shallow water table patterns with hard data (i.e., actual measurements that represent variation in the spatial structure of the shallow water table per rainfall event. The area used was a hillslope in the Catskill Mountains region of New York State. The shallow water table was monitored for a 120 m×180 m near-stream region at 44 sampling locations on 15-min intervals. Outflow of the area was measured at the same time interval. These data were analyzed at a short time interval (15 min and at a long time interval (months to characterize the changes in the hydrologic behavior of the hillslope. Indicator semivariograms based on binary-transformed ground water table data (i.e., 1 if exceeding the time-variable median depth to water table and 0 if not were created for both short and long time intervals. For the short time interval, the indicator semivariograms showed a high degree of spatial structure in the shallow water table for the spring, with increased range

  19. Regional water table (2014) in the Mojave River and Morongo Groundwater Basins, southwestern Mojave Desert, California

    Science.gov (United States)

    Teague, Nick F.; Stamos, Christina L.; House, Sally F.; Clark, Dennis A.

    2016-06-28

    2014 Water TableData for static water levels measured in about 610 wells during March–April 2014 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct this regional water-table map. This map shows the elevation of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater basins. Water levels recorded by the USGS and MWA staff were measured and compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). Water-level data submitted by cooperating local water districts were collected by using procedures established by the corresponding agency and were compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). All data were compared to historical data for qualityassurance purposes. Water-level contours from the 2012 water-level map (Teague and others, 2014) were used as a guide to interpret and shape the 2014 water-level contours in areas where 2014 water-level data were not available; these contours are shown as dashed (approximate) on this water-table map. Water-level data and contours are shown for the Warren subbasin in the Morongo groundwater basin in greater detail on inset A.The water table is the surface at which the fluid pressure in the pores of a porous medium is exactly atmospheric (Freeze and Cherry, 1979). The water table is defined by the level of the water surface in wells that just penetrate the top of the water body (Lohman, 1972). The water-level measurements used for the water-level contour maps are from wells that have more than one perforated interval in the saturated zone of the groundwater basins. Although these wells can have different perforated zones, the measured water levels from the zones were within about 10 feet (ft) and, therefore

  20. Estimated Depth to Ground Water and Configuration of the Water Table in the Portland, Oregon Area

    Science.gov (United States)

    Snyder, Daniel T.

    2008-01-01

    Reliable information on the configuration of the water table in the Portland metropolitan area is needed to address concerns about various water-resource issues, especially with regard to potential effects from stormwater injection systems such as UIC (underground injection control) systems that are either existing or planned. To help address these concerns, this report presents the estimated depth-to-water and water-table elevation maps for the Portland area, along with estimates of the relative uncertainty of the maps and seasonal water-table fluctuations. The method of analysis used to determine the water-table configuration in the Portland area relied on water-level data from shallow wells and surface-water features that are representative of the water table. However, the largest source of available well data is water-level measurements in reports filed by well constructors at the time of new well installation, but these data frequently were not representative of static water-level conditions. Depth-to-water measurements reported in well-construction records generally were shallower than measurements by the U.S. Geological Survey (USGS) in the same or nearby wells, although many depth-to-water measurements were substantially deeper than USGS measurements. Magnitudes of differences in depth-to-water measurements reported in well records and those measured by the USGS in the same or nearby wells ranged from -119 to 156 feet with a mean of the absolute value of the differences of 36 feet. One possible cause for the differences is that water levels in many wells reported in well records were not at equilibrium at the time of measurement. As a result, the analysis of the water-table configuration relied on water levels measured during the current study or used in previous USGS investigations in the Portland area. Because of the scarcity of well data in some areas, the locations of select surface-water features including major rivers, streams, lakes, wetlands, and

  1. Water Table Dynamics of a Rocky Mountain Riparian Area

    Science.gov (United States)

    Westbrook, C. J.

    2009-05-01

    Riparian areas in mountain valleys serve as collection points for local precipitation, hillslope runoff, deeper groundwater, and channel water. Little is known about how complex hydrological interactions among these water sources govern riparian water table dynamics, particularly on an event basis partly owing to a lack of high frequency spatial and temporal data. Herein I describe the magnitude and rate of change of groundwater storage in a 1.3 km2 Canadian Rocky Mountain peat riparian area. Weekly manual measurement of hydraulic heads in a network of 51 water table wells during the summers of 2006 and 2007 showed large temporal and spatial variations in well response. A near constant increase in the spatial heterogeneity of the water table was observed as the riparian area dried. Cluster analysis and principle components analysis were performed on these weekly data to objectively classify the riparian area into spatial response units. Results were classification of the standpipes into five distinct water table regimes. One well representing each water table regime was outfitted with a sensor in 2008 that measured hourly head, which was used to characterize temporal dynamics of water table response. In spring, snowmelt runoff combined with an ice lens 20-30 cm below the ground surface led to consistently high water tables throughout the riparian area. In summer, the water table fell throughout the riparian in response to declining hillslope inputs and increased evaporative demand, but rates of decline were highly variable among the water table regimes. Chloride concentrations suggest variability reflects differences in the degree to which the water table regimes are influenced by stream stage, hillslope inputs, and proximity to beaver dams. Water table regime responses to rain events were flashy, with dramatic rises and falls (up to 20 cm) in short periods of time (export and plant community composition.

  2. Decreased summer water table depth affects peatland vegetation

    NARCIS (Netherlands)

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

    2009-01-01

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

  3. Decreased summer water table depth affects peatland vegetation

    NARCIS (Netherlands)

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

    2009-01-01

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

  4. Significance testing testate amoeba water table reconstructions

    Science.gov (United States)

    Payne, Richard J.; Babeshko, Kirill V.; van Bellen, Simon; Blackford, Jeffrey J.; Booth, Robert K.; Charman, Dan J.; Ellershaw, Megan R.; Gilbert, Daniel; Hughes, Paul D. M.; Jassey, Vincent E. J.; Lamentowicz, Łukasz; Lamentowicz, Mariusz; Malysheva, Elena A.; Mauquoy, Dmitri; Mazei, Yuri; Mitchell, Edward A. D.; Swindles, Graeme T.; Tsyganov, Andrey N.; Turner, T. Edward; Telford, Richard J.

    2016-04-01

    Transfer functions are valuable tools in palaeoecology, but their output may not always be meaningful. A recently-developed statistical test ('randomTF') offers the potential to distinguish among reconstructions which are more likely to be useful, and those less so. We applied this test to a large number of reconstructions of peatland water table depth based on testate amoebae. Contrary to our expectations, a substantial majority (25 of 30) of these reconstructions gave non-significant results (P > 0.05). The underlying reasons for this outcome are unclear. We found no significant correlation between randomTF P-value and transfer function performance, the properties of the training set and reconstruction, or measures of transfer function fit. These results give cause for concern but we believe it would be extremely premature to discount the results of non-significant reconstructions. We stress the need for more critical assessment of transfer function output, replication of results and ecologically-informed interpretation of palaeoecological data.

  5. sir-06-5129_alt_water_table_con

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set consists of potentiometric contours that show lines of equal altitude of the generalized, long-term, regional water table in the...

  6. sir-06-5129_depth_water_table_con

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set consists of potentiometric contours that show lines of equal altitude of the generalized, long-term, regional water table in the...

  7. Upscaling of annual mean and dynamics of water table depth in German organic soils

    Science.gov (United States)

    Bechtold, Michel; Tiemeyer, Bärbel; Belting, Susanne; Laggner, Andreas; Leppelt, Thomas; Frahm, Enrico; Freibauer, Annette

    2013-04-01

    Water table depth is the key parameter controlling the fluxes of CO2, CH4 and N2O from organic soils (peatlands and other organic soils). Therefore, a good estimation of the spatial distribution of water table depth is crucial in any upscaling approach for these greenhouse gases (GHGs). It is further the prerequisite to assess the effects of re-wetting measures. There are attempts to obtain maps of water table depth at large scales (e.g. national or continental) by using process-based hydrological model concepts. However, major problem of the process-based approach is the representation of the water management (ditches, tile drains, pumping and weir management), which is at the best known spatially just for the ditch patterns. Thus, this approach is hardly applicable to the diversely-drained and -used organic soils in central Europe. Here, we present an alternative, data-driven approach for upscaling annual mean and dynamics of water table depth in organic soils. Groundwater level data of a unique dataset from about 60 peatlands, 1100 dipwells and around 8000 annual data sets, is the basis of this approach. Time series were used to calculate long-term annual means, average annual amplitudes and ponding durations. In case of continuous observations, shape parameters of the annual frequency distribution of water table depths were calculated. For each well, numerous site characteristics were collected as possible explanatory variables. This collection was restricted to nationally-available data. For each dipwell, land use is taken from official land use maps (German database ATKIS), and the soil type from the national geological map (1:200.000). In case of reliable site information, maps were corrected accordingly. Additionally, from these maps, topological indicators such as the ditch distance and density, the distance to the edge of the peatland and the peatland area within different buffers were calculated. Meteorological data (precipitation, potential

  8. ESTIMATION OF WATER TABLE ELEVATION BY UNIVERSAL COKRIGING

    Institute of Scientific and Technical Information of China (English)

    CHEN Jia-jun; TIAN Kai-ming; GUO Qiao-yu

    2005-01-01

    When water resource or quality problems associated with phreatic water in geological settings are studied, information about water table elevations is often crucial.In those cases where the water table is a subdued replica of the ground surface, universal cokriging can be used to estimate water table elevations at un-sampled locations on the basis of water table and ground surface elevation measurements obtained at well locations.In this paper, universal cokriging, with ground surface elevation considered as a co-variate, was used to estimate water table elevations.Universal cokriging equations were derived, an iterative method for obtaining experimental variograms was established, and a case study of an initial groundwater flow simulation in the Xiuwu County, Henan Province, China, was presented.In the case study, the initial groundwater flow regime was represented both by universal cokriging with the ground surface elevation serving as a covariate and by universal kriging without the inclusion of ground surface elevation as a covariate.A comparison of the results from these two approaches shows that groundwater levels of phreatic water at locations without measurements in regions with unconsolidated porous media can be estimated more accurately by universal cokriging.

  9. Model for a dune field with exposed water table

    CERN Document Server

    Luna, Marco Cesar M de M; Herrmann, Hans J

    2011-01-01

    Aeolian transport in coastal areas can be significantly affected by the presence of an exposed water table. In some dune fields, such as in Len\\c{c}\\'ois Maranhenses, northeastern Brazil, the water table oscillates in response to seasonal changes of rainfall and rates of evapotranspiration, rising above the ground during the wet season and sinking below in the dry period. A quantitative understanding of dune mobility in an environment with varying groundwater level is essential for coastal management as well as for the study of long-term evolution of many dune fields. Here we apply a model for aeolian dunes to study the genesis of coastal dune fields in presence of an oscillating water table. We find that the morphology of the field depends on the time cycle, $T_{\\mathrm{w}}$, of the water table and the maximum height, $H_{\\mathrm{w}}$, of its oscillation. Our calculations show that long chains of barchanoids alternating with interdune ponds such as found at Len\\c{c}\\'ois Maranhenses arise when $T_{\\mathrm{w}...

  10. Determination of vulnerability areas to pollution: case of alluvial water table of Tebessa (East Algeria)

    Energy Technology Data Exchange (ETDEWEB)

    Djabri, L.; Hani, A.; Assassi, F.; Djprfi, S.

    2009-07-01

    This work related to the alluvial water table of Tebessa, which is characterised by a semi-dry climate and a very heterogeneous geology. To examine the pollution problem who seems exists, we have used two methods: the DRASTICS method who combines the information given by the seven parameters leading to the map of vulnerability to pollution and a second method that is based on hydrochemistry and take into account the results of the ratio Sr{sup 2}/Ca{sup 2}+. (Author)

  11. Exploring Soil Layers and Water Tables with Ground-Penetrating Radar

    Institute of Scientific and Technical Information of China (English)

    K. ROTH; U. WOLLSCHLAGER; CHENG Zhu-Hua; ZHANG Jia-Bao

    2004-01-01

    Ground-penetrating radar (GPR) has been used predominantly for environments with low electrical conductivity like freshwater aquifers, glaciers, or dry sandy soils. The objective of the present study was to explore its application for mapping in subsurface agricultural soils to a depth of several meters. For a loamy sand and a clayey site on the North China Plain, clay inclusions in the sand were detected; the thickness, inclination, and continuity of the confining clay and silt layers was assessed; and a local water table was mapped. Direct sampling (soil coring and profiling) in the top meter and independent measurement of the water table were utilized to confirm the findings. Also, effective estimates of the dielectric number for the site with the dielectric number of moist clayey soils depending strongly on frequency were obtained. Thus, important properties of soils, like the arrangement and type of layers and in particular their continuity and inclination, could be explored with moderate efforts for rather large areas to help find optimal locations for the time-consuming and expensive measurements which would be necessary to detail a model of the subsurface.

  12. Enhanced migratory waterfowl distribution modeling by inclusion of depth to water table data.

    Directory of Open Access Journals (Sweden)

    Betty J Kreakie

    Full Text Available In addition to being used as a tool for ecological understanding, management and conservation of migratory waterfowl rely heavily on distribution models; yet these models have poor accuracy when compared to models of other bird groups. The goal of this study is to offer methods to enhance our ability to accurately model the spatial distributions of six migratory waterfowl species. This goal is accomplished by creating models based on species-specific annual cycles and introducing a depth to water table (DWT data set. The DWT data set, a wetland proxy, is a simulated long-term measure of the point either at or below the surface where climate and geological/topographic water fluxes balance. For species occurrences, the USGS' banding bird data for six relatively common species was used. Distribution models are constructed using Random Forest and MaxEnt. Random Forest classification of habitat and non-habitat provided a measure of DWT variable importance, which indicated that DWT is as important, and often more important, to model accuracy as temperature, precipitation, elevation, and an alternative wetland measure. MaxEnt models that included DWT in addition to traditional predictor variables had a considerable increase in classification accuracy. Also, MaxEnt models created with DWT often had higher accuracy when compared with models created with an alternative measure of wetland habitat. By comparing maps of predicted probability of occurrence and response curves, it is possible to explore how different species respond to water table depth and how a species responds in different seasons. The results of this analysis also illustrate that, as expected, all waterfowl species are tightly affiliated with shallow water table habitat. However, this study illustrates that the intensity of affiliation is not constant between seasons for a species, nor is it consistent between species.

  13. Water-Table and Potentiometric-Surface Altitudes in the Upper Glacial, Magothy, and Lloyd Aquifers beneath Long Island, New York, March-April 2006

    Science.gov (United States)

    Monti, Jack; Busciolano, Ronald J.

    2009-01-01

    The U.S. Geological Survey (USGS), in cooperation with State and local agencies, systematically collects ground-water data at varying measurement frequencies to monitor the hydrologic situation on Long Island, New York. Each year during March and April, the USGS conducts a synoptic survey of hydrologic conditions to define the spatial distribution of the water table and potentiometric surfaces within the three main water-bearing units underlying Long Island - the upper glacial, Magothy, and Lloyd aquifers. These data and the maps constructed from them are commonly used in studies of Long Island's hydrology, and by water managers and suppliers for aquifer management and planning purposes. Water-level measurements made in 502 wells across Long Island during March-April 2006, were used to prepare the maps in this report. Measurements were made by the wetted-tape method to the nearest hundredth of a foot. Water-table and potentiometric-surface altitudes in these aquifers were contoured using these measurements. The water-table contours were interpreted using water-level data collected from 341 wells screened in the upper glacial aquifer and (or) shallow Magothy aquifer; the Magothy aquifer's potentiometric-surface contours were interpreted from measurements at 102 wells screened in the middle to deep Magothy aquifer and (or) contiguous and hydraulically connected Jameco aquifer; and the Lloyd aquifer's potentiometric-surface contours were interpreted from measurements at 59 wells screened in the Lloyd aquifer or contiguous and hydraulically connected North Shore aquifer. Many of the supply wells are in continuous operation and, therefore, were turned off for a minimum of 24 hours before measurements were made so that the water levels in the wells could recover to the level of the potentiometric head in the surrounding aquifer. Full recovery time at some of these supply wells can exceed 24 hours; therefore, water levels measured at these wells are assumed to be less

  14. Geomorphological control of water tables in a blanket peat landscape: implications for carbon cycling

    Science.gov (United States)

    Allott, Tim; Evans, Martin; Lindsay, John; Agnew, Clive; Freer, Jim

    2010-05-01

    Water tables are an important control on carbon cycling and rates of carbon sequestration in peatland systems, and water table depth is therefore a key parameter in carbon models for blanket peat systems. Although there is a wide literature on blanket peat hydrology, including studies which specifically evaluate water table conditions, detailed data on water table behaviour and variability at the landscape scale are sparse. In particular, many British blanket peats are affected by gully erosion and this has been generally assumed to influence water table conditions. However, there has been limited evaluation of this geomomorphological control on peatland water tables. This paper presents results from a project which evaluated water table conditions in the blanket peatlands of the Peak District National Park, UK. A key aim was to quantify the impact of gully erosion on peatland water tables. A detailed programme of water table monitoring was undertaken during 2008/09, involving regular measurements of water table depth in over 530 dipwells at 19 sites across the 47 km2 peatland landscape of the Kinder Scout / Bleaklow area. This included a campaign of regular, simultaneous water table measurements from clusters of dipwells at the main sites, supplemented by continuous (hourly) water table monitoring in selected dipwells. It also included studies to evaluate within-site variation in water table conditions and local water table drawdown effects associated with gully erosion. Results indicate that gully erosion causes water table drawdown through two distinct processes. The first is local water table drawdown immediately adjacent to erosion gullies. This effect is restricted to a zone within 2 m of gully edges, and water tables within the gully edge drawdown zone are approximately 200 mm lower than in the adjacent peatland. The second effect is a more general water table lowering at eroded sites, with median water table depths at heavily eroded sites up to 300 mm lower

  15. WATER TABLE AND REDOX CONDITIONS IN DEEP TROPICAL PEAT

    Institute of Scientific and Technical Information of China (English)

    Hajah Dulima Jali

    2007-01-01

    Redox potential in the well developed tropical peat swamp in Brunei was studied for a year. Generally the redox potential measurements showed a large variation, ranging from -234 mV to 727 mV. The expected rise in redox values did not take place following the drop of water table during the dry months of June to September. The redox value at 100 cm depth indicated that the soil remained reduced throughout the year in spite of the lowering of water table below 150 cm in all sites during dry period. Similarly the redox values did not decrease rapidly following flooding when the water table rose to the surface. This phenomenon could be attributed to the topography of the peat dome which facilitated the fast lateral movement of water and thus promoted oxygen supply down the peat profile, though not great enough to reach the 100 cm depth. The rapid lateral flow of water in the outer Alan batu site facilitated aeration, but in the inner sites remained which was reduced because of the slower water movement. The slower initiation of the reducing condition was likely due to the presence of nitrate which has accumulated as a result of ammonium oxidation during the relatively long aerobic period. Differences in the distribution of redox potential with depth are possibly explained by the different permeability of peat affecting flow patterns and residence time of water. The nature and compactibility of the peat might have slowed the diffusion rates of O2 into the lower layer. Though the bulk density of the peat was low, the composition of the peat might influence the peat permeability and hydraulic conductivity. The tree trunks are not decomposed or large branches must have lowered permeability compared to the other peat material.

  16. EFFECTS OF WATER TABLE AND NITROGEN ADDITION ON CO2 EMISSION FROM WETLAND SOIL

    Institute of Scientific and Technical Information of China (English)

    YANG Ji-song; LIU Jing-shuang; YU Jun-bao; WANG Jin-da; QIN Sheng-jin; LI Xin-hua

    2005-01-01

    Soil respiration is a main dynamic process of carbon cycle in wetland. It is important to contribute to global climate changes. Water table and nutritious availability are significant impact factors to influence responses of CO2 emission from wetland soil to climate changes. Twenty-four wetland soil monoliths at 4 water-table positions and in 3 nitrogen status have been incubated to measure rates of CO2 emission from wetland soils in this study.Three static water-table controls and a fluctuant water-table control, with 3 nitrogen additions in every water-table control,were carried out. In no nitrogen addition treatment, high CO2 emissions were found at a static low water table ( Ⅰ )and a fluctuant water table (Ⅳ),averaging 306.7mg/(m2·h) and 307.89mg/(m2·h), respectively, which were 51%-57% higher than that at static high water table ( Ⅱ and Ⅲ). After nitrogen addition, however, highest CO2 emission was found at Ⅱ and lowest emission at Ⅲ. The results suggested that nutritious availability of wetland soil might be important to influence the effect of water table on the CO2 emission from the wetland soil. Nitrogen addition led to enhancing CO2 emissions from wetland soil, while the highest emission was found in 1N treatments other than in 2N treatments. In 3 nutritious treatments,low CO2 emissions at high water tables and high CO2 emissions at low water tables were also observed when water table fluctuated. Our results suggested that both water table changes and nutritious imports would effect the CO2 emission from wetland.

  17. Preface: The Environmental Mapping and Analysis Program (EnMAP Mission: Preparing for Its Scientific Exploitation

    Directory of Open Access Journals (Sweden)

    Saskia Foerster

    2016-11-01

    Full Text Available The imaging spectroscopy mission EnMAP aims to assess the state and evolution of terrestrial and aquatic ecosystems, examine the multifaceted impacts of human activities, and support a sustainable use of natural resources. Once in operation (scheduled to launch in 2019, EnMAP will provide high-quality observations in the visible to near-infrared and shortwave-infrared spectral range. The scientific preparation of the mission comprises an extensive science program. This special issue presents a collection of research articles, demonstrating the potential of EnMAP for various applications along with overview articles on the mission and software tools developed within its scientific preparation.

  18. Potential for water-table excursions induced by seismic events at Yucca Mountain, Nevada

    Science.gov (United States)

    Carrigan, Charles R.; King, Geoffrey C. P.; Barr, George E.; Bixler, Nathan E.

    1991-12-01

    The possibility that 100-200 m changes in water-table elevation can be mechanically induced by earthquakes is a consideration in site studies of a potential high-level nuclear waste repository at Yucca Mountain, Nevada. However, numerical simulations of tectonohydrologic coupling involving earthquakes typical of the Basin and Range province produce 2-3 m excursions of a water table that is 500 m below the land surface. Even displacements corresponding to extraordinary seismic events drive water-table excursions of less than 20 m. Flow resulting from earthquake-induced pore-pressure fields below the water table tends to be mainly horizontal; vertical flows that cause changes of the level of the water table are secondary. Strongly anisotropic permeability, intended to enhance vertical flow within fault zones, only doubles water-table rise in the models considered. These simulations of water-table rise compare well with observations following large earthquakes in the Basin and Range. Our models suggest that exceptional hydrologic and/or tectonic conditions would be required to produce substantially larger water-table rises.

  19. Model-based Acceleration of Parameter mapping (MAP) for saturation prepared radially acquired data.

    Science.gov (United States)

    Tran-Gia, Johannes; Stäb, Daniel; Wech, Tobias; Hahn, Dietbert; Köstler, Herbert

    2013-12-01

    A reconstruction technique called Model-based Acceleration of Parameter mapping (MAP) is presented allowing for quantification of longitudinal relaxation time and proton density from radial single-shot measurements after saturation recovery magnetization preparation. Using a mono-exponential model in image space, an iterative fitting algorithm is used to reconstruct one well resolved and consistent image for each of the projections acquired during the saturation recovery relaxation process. The functionality of the algorithm is examined in numerical simulations, phantom experiments, and in-vivo studies. MAP reconstructions of single-shot acquisitions feature the same image quality and resolution as fully sampled reference images in phantom and in-vivo studies. The longitudinal relaxation times obtained from the MAP reconstructions are in very good agreement with the reference values in numerical simulations as well as phantom and in-vivo measurements. Compared to available contrast manipulation techniques, no averaging of projections acquired at different time points of the relaxation process is required in MAP imaging. The proposed technique offers new ways of extracting quantitative information from single-shot measurements acquired after magnetization preparation. The reconstruction simultaneously yields images with high spatiotemporal resolution fully consistent with the acquired data as well as maps of the effective longitudinal relaxation parameter and the relative proton density. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  20. Water-table and Potentiometric-surface altitudes in the Upper Glacial, Magothy, and Lloyd aquifers beneath Long Island, New York, April-May 2010

    Science.gov (United States)

    Monti, Jack; Como, Michael D.; Busciolano, Ronald

    2013-01-01

    The U.S. Geological Survey (USGS), in cooperation with State and local agencies, systematically collects groundwater data at varying measurement frequencies to monitor the hydrologic conditions on Long Island, New York. Each year during April and May, the USGS conducts a synoptic survey of water levels to define the spatial distribution of the water table and potentiometric surfaces within the three main water-bearing units underlying Long Island—the upper glacial, Magothy, and Lloyd aquifers (Smolensky and others, 1989)—and the hydraulically connected Jameco (Soren, 1971) and North Shore aquifers (Stumm, 2001). These data and the maps constructed from them are commonly used in studies of Long Island’s hydrology and are used by water managers and suppliers for aquifer management and planning purposes. Water-level measurements made in 503 monitoring wells, a network of observation and supply wells, and 16 streamgage locations across Long Island during April–May 2010 were used to prepare the maps in this report. Measurements were made by the wetted-tape method to the nearest hundredth of a foot. Water-table and potentiometric-surface altitudes in these aquifers were contoured by using these measurements. The water-table contours were interpreted by using water-level data collected from 16 streamgages, 349 observation wells, and 1 supply well screened in the upper glacial aquifer and (or) shallow Magothy aquifer; the Magothy aquifer’s potentiometric-surface contours were interpreted from measurements at 67 observation wells and 27 supply wells screened in the middle to deep Magothy aquifer and (or) the contiguous and hydraulically connected Jameco aquifer. The Lloyd aquifer’s potentiometric-surface contours were interpreted from measurements at 55 observation wells and 4 supply wells screened in the Lloyd aquifer or the contiguous and hydraulically connected North Shore aquifer. Many of the supply wells are in continuous operation and, therefore, were

  1. Unraveling uncertainties of water table slope assessment with DGPS in lowland floodplain wetlands.

    Science.gov (United States)

    Mirosław-Świątek, Dorota; Michałowski, Robert; Szporak-Wasilewska, Sylwia; Ignar, Stefan; Grygoruk, Mateusz

    2016-11-01

    In our study, we analyzed the combined standard uncertainty of water table slope assessment done using differential global positioning system (DGPS)-based measurements of water table elevation and distances between measurement locations. We compared and discussed uncertainties in water table slope assessments done in various hypothetical environments of lowland floodplains (water table slopes typically ranged from 1.25 · 10(-4) to 1 · 10(-3)). Our analyses referred to elevation measurements done with the static GPS and DGPS real-time kinematic (RTK) approaches, which are currently among the most frequently used elevation measurement techniques worldwide. Calculations of the combined standard uncertainty of water table slope allowed us to conclude that the DGPS-RTK approach used in water table slope assessment can result in assessment errors as high as 50 % at short (<200 m) distances. Acceptable water table slope measurement errors (lower than 5 %) occur at distances longer than 11,320 m in the case of DGPS-RTK measurements, while, in the case of static GPS measurements, acceptable measurement errors at the same level occur at distances as low as 1350 m. Errors in water table slope assessment as high as 50 % occur at distances of 1130 m and 140 m for DGPS-RTK and static GPS measurements, respectively. We conclude that, although the DGPS-RTK methodology-due to its ease of use and time-saving capabilities is very often applied to water level measurements in lowland riparian wetlands, the application of the DGPS-RTK methodology for water table slope assessment at distances shorter than a few couples of meters results in very low accuracy (errors greater than 50 %) and should not be used for calculating local slopes in low slope areas such as lowland riparian zones.

  2. Effects of Mind Map Supported Cognitive Preparation on Expository Writing

    Directory of Open Access Journals (Sweden)

    H. Ömer BEYDOĞAN

    2011-12-01

    Full Text Available Written expression, due to the uncertainties and difficulties is a problem for an individual. The individual is expected to conduct cognitive preparation to overcome this problem. In present study written expression skill differentiations in students who are, prior to written expression performance, assisted cognitively via activities like brain storming, clustering and mind map have been analyzed. To that end randomly selected 64 freshmen students from Faculty of Education have composed the research sampling. In this research pre-test and post-test model centered experiment and control groups have been utilized. Data have been obtained from “Written Expression Evaluation Scale” developed by the researcher. In data analysis arithmetical means, standard deviation, Manova and t test technique have been used. It has been determined that experiment group students who, prior to written expression performance, conducted cognitive preparations via activities such as free writing, brain storming, clustering and mind map have created, in certain dimensions of the scale, better explanatory writing texts than the students in control group. Within the framework of obtained data, certain suggestions on mental preparation prior to written expression have been presented.

  3. Altitude of water table, surficial aquifer, Palm Beach County, Florida, April 24-26, 1984

    Science.gov (United States)

    Miller, Wesley L.

    1985-01-01

    Water levels in Palm Beach County, Florida, were measured in April 1984 to determine the altitude of the water table in the surficial aquifer. A total of 104 wells and 50 surface-water measurement sites were used to contour the altitude of the water table at 2 and 4-foot intervals. The water-level measurements made in April represent low-water levels near the end of south Florida 's dry season. Contours of the water table at this time ranged from 22 feet above sea level in the north-central part of the county to 2 feet near the coast. (USGS)

  4. Water Tables, Flooding, and Water Use by Riparian Phreatophyte Communities

    Science.gov (United States)

    Thibault, J. R.; Cleverly, J. R.; Dahm, C.

    2010-12-01

    Phreatophytic riparian vegetation relies heavily on ground water transported from upstream sources. In the American southwest, the phenology of native phreatophytes, e.g., Rio Grande cottonwood, (Populus deltoides) is also dependent on seasonal flooding, which has been greatly diminished by hydrologic alterations and competing allocations. In this semi-arid, water-scarce region, a long history of agriculture and a rapidly expanding population impose limits on water available for ecological purposes, such as managed, restorative flooding. At native and non-native (e.g., saltcedar, (Tamarix spp.)) sites along the Rio Grande floodplain of central New Mexico, eddy covariance flux towers and monitoring wells are deployed to quantify evapotranspiration (ET) and investigate relationships between ET, water table (WT) depth, and flooding. Season-long measurements have been completed over several years in flooding and non-flooding sites under climatic conditions fluctuating from wet to extreme drought. Total growing season ET declines with deeper WTs across sites, with robust correlations where strong hydrologic connections exist between the river and ground water. As such, wet years with elevated WTs result in greater annual ET. However, ET responds less clearly to floods within the growing season. Longer duration floods lasting several weeks are more typical earlier in the growing season, associated with sufficient snowmelt runoff. Extensive spring flooding in two recent years coincided with significantly higher ET at a young, mixed stand, but had no effect on ET at a mature saltcedar forest. Summer monsoons and drier springs typically bring more transitory flood pulses with rapid WT ascent and decline measured in days. Elevated ET occurred during only one of several shorter flood pulses, at a saltcedar site during an otherwise dry spring. ET was not affected by monsoon flood pulses. Recruitment of native vegetation requires spring floods with favorable timing, magnitude

  5. Spring 1961 water table of California's Central Valley (from Williamson and others, 1989)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset defines the spring 1961 water-table altitude for the California's Central Valley. It was used to initiate the water-level altitudes for the...

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

    DEFF Research Database (Denmark)

    Grathwohl, Peter; Haberer, Cristina; Ye, Yu;

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

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

    Science.gov (United States)

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

    2014-02-01

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

  8. Testing peatland water-table depth transfer functions using high-resolution hydrological monitoring data

    Science.gov (United States)

    Swindles, Graeme T.; Holden, Joseph; Raby, Cassandra L.; Turner, T. Edward; Blundell, Antony; Charman, Dan J.; Menberu, Meseret Walle; Kløve, Bjørn

    2015-07-01

    Transfer functions are now commonly used to reconstruct past environmental variability from palaeoecological data. However, such approaches need to be critically appraised. Testate amoeba-based transfer functions are an established method for the quantitative reconstruction of past water-table variations in peatlands, and have been applied to research questions in palaeoclimatology, peatland ecohydrology and archaeology. We analysed automatically-logged peatland water-table data from dipwells located in England, Wales and Finland and a suite of three year, one year and summer water-table statistics were calculated from each location. Surface moss samples were extracted from beside each dipwell and the testate amoebae community composition was determined. Two published transfer functions were applied to the testate-amoeba data for prediction of water-table depth (England and Europe). Our results show that estimated water-table depths based on the testate amoeba community reflect directional changes, but that they are poor representations of the real mean or median water-table magnitudes for the study sites. We suggest that although testate amoeba-based reconstructions can be used to identify past shifts in peat hydrology, they cannot currently be used to establish precise hydrological baselines such as those needed to inform management and restoration of peatlands. One approach to avoid confusion with contemporary water-table determinations is to use residuals or standardised values for peatland water-table reconstructions. We contend that our test of transfer functions against independent instrumental data sets may be more powerful than relying on statistical testing alone.

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

    Science.gov (United States)

    Meitner, P. L.

    1974-01-01

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

  10. Spatial relationship of groundwater arsenic distribution with regional topography and water-table fluctuations in the shallow aquifers in Bangladesh

    Science.gov (United States)

    Shamsudduha, M.; Marzen, L. J.; Uddin, A.; Lee, M.-K.; Saunders, J. A.

    2009-06-01

    The present study has examined the relationship of groundwater arsenic (As) levels in alluvial aquifers with topographic elevation, slope, and groundwater level on a large basinal-scale using high-resolution (90 m × 90 m) Shuttle Radar Topography Mission (SRTM) digital elevation model and water-table data in Bangladesh. Results show that high As (>50 μg/l) tubewells are located in low-lying areas, where mean surface elevation is approximately 10 m. Similarly, high As concentrations are found within extremely low slopes (Bangladesh Water Development Board) was mapped using water-table data from 950 shallow (depth Works Datum (PWD) level. Extremely low groundwater gradients (0.01-0.001 m/km) within the GBM delta complex hinder groundwater flow and cause slow flushing of aquifers. Low elevation and gentle slope favor accumulation of finer sediments, As-carrying iron-oxyhydroxide minerals, and abundant organic matter within floodplains and alluvial deposits. At low horizontal hydraulic gradients and under reducing conditions, As is released in groundwater by microbial activity, causing widespread contamination in the low-lying deltaic and floodplain areas, where As is being recycled with time due to complex biogeochemical processes.

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

    Science.gov (United States)

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

    2013-01-01

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

  12. Modeling water table fluctuations by means of a stochastic differential equation

    Science.gov (United States)

    Bierkens, Marc F. P.

    1998-10-01

    The combined system of soil-water and shallow groundwater is modeled with simple mass balance equations assuming equilibrium soil moisture conditions. This results in an ordinary but nonlinear differential equation of water table depth at a single location. If errors in model inputs, errors due to model assumptions and parameter uncertainty are lumped and modeled as a wide band noise process, a stochastic differential equation (SDE) results. A solution for the stationary probability density function is given through use of the Fokker-Planck equation. For the nonstationary case, where the model inputs are given as daily time series, sample functions of water table depth, soil saturation, and drainage discharge can be simulated by numerically solving the SDE. These sample functions can be used for designing drainage systems and to perform risk analyses. The parameters and noise statistics of the SDE are calibrated on time series of water table depths by embedding the SDE in a Kaiman filter algorithm and using the filter innovations in a filter-type maximum likelihood criterion. The stochastic model is calibrated and validated at two locations: a peat soil with a very shallow water table and a loamy sand soil with a moderately shallow water table. It is shown in both cases that sample functions simulated with the SDE are able to reproduce a wide range of statistics of water table depth. Despite its unrealistic assumption of constant inputs, the stationary solution derived from the Fokker-Planck equation gives good results for the peat soil, most likely because the characteristic response time of the water table is very small.

  13. The complex relationships between methane emissions and water table at an ombrotrophic bog

    Science.gov (United States)

    Humphreys, Elyn; Roulet, Nigel; Moore, Tim

    2017-04-01

    Broad spatial and temporal variations in methane emissions from peatlands have been related to many variables including water table position, temperature and vegetation characteristics and functioning. In general, wetter peatlands tend to have greater methane emissions. However, over shorter periods of time and space, the relationship between water table and methane emissions can reverse, show hysteresis or be absent entirely. These relationships are investigated at the Mer Bleue Bog, a temperate ombrotrophic bog near Ottawa, Canada. Six years of concurrent growing season eddy covariance and automated chamber fluxes reveal the expected broad patterns. During the wettest growing season, the water table remained within 40 cm of the bog's hummock surfaces. Methane emissions were upwards of 20 to 45 mg C m-2 d-1 and exceeded the emission rates from two drier growing seasons which saw periods where the water table dropped to nearly 80 cm below the hummock surface. In those periods, methane emission rates declined to about 5 mg C m-2 d-1 or less. Lawn plots with aerenchymatous Eriophorum vegetation and high water tables had greatest emissions (exceeding 200 mg C m-2 d-1) compared to hummock plots vegetated by ericaceous shrubs, which had emissions rates similar to those measured by eddy covariance. However, within a growing season, hysteresis and inverse relationships between water table and methane emissions were observed at both ecosystem and chamber plot scales. These included periods between rainfall events where methane emissions increased while the water table deepened. The potential roles of methane production, consumption, storage and transport processes on these patterns will be discussed.

  14. A diagnosis of sub-surface water table dynamics in low hydraulic conductivity soils in the sugar cane fields of Pongola, South Africa

    Science.gov (United States)

    Malota, Mphatso; Senzanje, Aidan

    2016-04-01

    Water and land are the two natural resources restraining crop production in South Africa. With the increasing demand for food, emphasis has shifted from the sole reliance on rain fed crop production, to irrigation. The deterioration in irrigation water quality from surface water sources is, however, posing a big challenge to the sustainability of irrigated crop production. This is because more water is required for leaching, resulting in shallow water tables in agricultural lands. The installation of well designed subsurface drainage systems alone is not enough; the provision of timely maintenance is also necessary. In this study, the extent and severity of problems as a consequence of shallow water tables and their possible causes were investigated at three sugarcane fields in Pongola, South Africa, having low hydraulic conductivity soils. Also investigated were soil salinity levels and the temporal variation in the salinity of the irrigation water. A water table map of a 32 ha sugarcane field was generated, using observed water table depth (WTD) data from 36 piezometers monitored from September 2011 to February 2012. Out of the total 32 ha under cultivation, 12% was found to be affected by shallow WTDs of less than the 1.0 m design WTD. The inability of natural drainage to cope with subsurface drainage needs and the poor maintenance of subsurface drainage systems contributed to the shallow water tables in the area. Furthermore, the currently adopted drainage design criteria also proved unsatisfactory with mean observed water table depth and drainage discharge (DD) of 20% and 50%, respectively, less than their respective design levels. The salinity of the irrigation water was, on average, 32% higher than threshold tolerance level of sugarcane. The root zone soil salinity levels at the three study sites were greater than the 1.7 dS m-1 threshold for sugar cane. The subsurface drainage design criteria adopted at the site needs to be revisited by ensuring that the

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

    DEFF Research Database (Denmark)

    Tiiva, Päivi; Faubert, Patrick; Räty, Sanna;

    2009-01-01

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

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

    Science.gov (United States)

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

    2008-01-01

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

  17. Effects of long-term water table drawdown on evapotranspiration and vegetation in an arid region phreatophyte community

    Science.gov (United States)

    Cooper, David J.; Sanderson, John S.; Stannard, David I.; Groeneveld, David P.

    2006-06-01

    Evapotranspiration rates and the ground water component of evapotranspiration at a site in Colorado's San Luis Valley that is dominated by shrubby phreatophytes (greasewood and rabbitbrush) were compared before and after a water table drawdown. Evapotranspiration (ET) rates at the site were first measured in 1985-1987 (pre-drawdown) when the mean water table depth was 0.92 m. Regional ground water pumping has since lowered the water table by 1.58 m, to a mean of 2.50 m. We measured ET at the same site in 1999-2003 (post-drawdown), and assessed physical and biological factors affecting the response of ET to water table drawdown. Vegetation changed markedly from the pre-drawdown to the post-drawdown period as phreatophytic shrubs invaded former wetland areas, and wetland grasses and grass-like species decreased. Lowering the water table reduced estimated total annual ET from a mean of 409.0 to 278.0 mm, a decrease of 32%, and the ground water component of ET (ET g), from a mean of 226.6 to 86.5 mm, a decrease of 62%. Two water table depth/ET models that have been used in the San Luis Valley overestimated the reduction in ET g due to lowering the water table by as much as 253%. While our results corroborate the generally observed negative correlation between ET rates and water table depth, they demonstrate that specific models to estimate ET as a function of water table depth, if not verified, may be prone to large errors. Both the water table drawdown and the vegetation change are continuing 20 years after the drawdown began, and it is unclear how site ET rates and processes will differ after the water table has stabilized and vegetation has adjusted to the new site hydrologic conditions.

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

    Science.gov (United States)

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

    2014-09-01

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

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

    Directory of Open Access Journals (Sweden)

    M. Bechtold

    2014-04-01

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

  20. Coupling WRF with LEAFHYDRO: introducing groundwater and a fully dynamic water table in regional climate simulations

    Science.gov (United States)

    Martínez de La Torre, A.; Rios Entenza, A.; Gestal Souto, L.; Miguez Macho, G.

    2010-09-01

    Here we present a soil-vegetation-hydrology model, LEAFHYDRO coupled with the WRF model. LEAFHYDRO includes a groundwater parameterization with a dynamic water table and river routing and it can be run at a finer resolution than the atmosphere within WRF. Offline multiyear simulations over the Iberian Peninsula at 2.5 km resolution with the LEAFHYDRO model with and without groundwater indicate that introducing the water table parameterization has a significant impact on soil moisture amounts, soil moisture persistence and evapotranspiration fluxes. This is particularly true over the semiarid flat plateaus of the Iberian interior, where the atmospheric source of precipitation is scarce and the water table is naturally shallow due to slow drainage and lateral flow convergence from the surrounding mountains. Climatic simulations with the coupled WRF-HYDRO system suggest that the memory induced in the soil by the water table significantly impact the simulated precipitation, especially in the spring, when the land-surface atmospheric coupling is strong and rainfall amounts have their annual peak inland Iberia.

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

    Science.gov (United States)

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

    2013-01-01

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

  2. Effects of site characteristics on cumulative frequency distribution of water table depth in peatlands

    Science.gov (United States)

    Bechtold, Michel; Tiemeyer, Bärbel; Frahm, Enrico; Roßkopf, Niko

    2013-04-01

    Previous studies demonstrated strong dependency of vegetation development and GHG emissions from peatlands on annual mean water table depth. It is also proposed that the duration of ponding and low water level periods are important indicators for CH4 emissions and the presence of specific plant species. Better understanding of the annual water table dynamics and the influence of site characteristics helps to explain variability of vegetation and emissions at the plot scale. It also provides essential information for a nation-wide upscaling of local gas flux measurements and for estimating the impact of regional adaption strategies. In this study, we analyze the influence of site characteristics on the cumulative frequency distribution of water table depth in a peatland. On the basis of data from about 100 sites we evaluate how distribution functions, e.g. the beta distribution function, are a tool for the systematic analysis of the site-specific frequency distribution of water table depth. Our analysis shows that it is possible to differentiate different shape types of frequency distributions, in particular left-skewed (bias towards the water table minimum), right-skewed (bias towards the water table maximum), and 'S'-shaped distributions (bias towards the mid of min and max). The shape is primarily dependent on the annual mean water table depth, but also shows dependencies on land use, peatland type, catchment size and soil properties. Forest soils are for example all characterized by a 'S'-shaped distribution. Preliminary results indicate that data sets that do not show a beta distribution are mostly from observation wells that are located close to drainage courses and/or are from sites characterized by strong water management (e.g. abruptly changing weir levels). The beta distribution might thus be a tool to identify sites with a 'non-natural' frequency distribution or erroneous data sets. Because the parameters of the beta distribution show a dependency on site

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

    Energy Technology Data Exchange (ETDEWEB)

    Asrari, E.; Masoudi, M.

    2009-07-01

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

  4. Effects of a fluctuating water table : Column study on redox dynamics and fate of some organic pollutants

    NARCIS (Netherlands)

    Sinke, A.J.C.; Dury, O.; Zobrist, J.

    1998-01-01

    The development of the redox conditions has been studied in an initially aerobic column filled with quartz sand coated with ferrihydrite and subjected to a fluctuating water table. The purpose of this study was to evaluate the effect of water table fluctuations on the redox dynamics and the fate of

  5. Large water-table response to rainfall in a shallow bedrock aquifer having minimal overburden cover

    Science.gov (United States)

    Miles, Owen W.; Novakowski, Kent S.

    2016-10-01

    Rapid recharge events manifested as significant increases in hydraulic head have been observed in many fractured bedrock aquifers around the world. Often the response in hydraulic head exceeds what would be observed in an equivalent porous media by more than an order of magnitude. As the mechanisms that cause these events are poorly understood particularly under highly-transient conditions, a detailed investigation was conducted at a well-characterized field site in eastern Canada. During the spring and summer of 2012, frequent measurements of hydraulic head were obtained in gneissic terrain covered by a thin veneer of drift materials using 21 multi-level monitoring wells installed in the bedrock. Each of the wells was hydraulically tested from the water table to total depth using a straddle-packer system and fractures intersecting the wells were identified using a borehole camera prior to the construction of the multi-level piezometers. Rainfall and weather data were also collected over the same time period. A piezometer located on a bedrock outcrop which responded rapidly to rainfall was identified and used as a focus for numerical simulations. To determine the properties of the drift materials in the vicinity of the outcrop, a ground penetrating radar (GPR) survey was conducted over a 40 × 40 m area to map depth to bedrock and five in-situ permeameter tests were performed to estimate the hydraulic conductivity. Three-dimensional numerical simulations were conducted to reproduce the response in the piezometer for both short (24 h) and long (one month) timescales. The numerical simulations were used to determine what parameters have the greatest impact on controlling rapid recharge. Based on this study it was concluded that the large magnitude head rises recorded in this piezometer are a result of recharge to steeply inclined fractures exposed on or immediately adjacent to the outcrop. The hydraulic head responds rapidly because of the low specific yield of the

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

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2012-11-01

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

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

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2012-05-01

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

  8. Remediation of NAPL below the water table by steam-induced heat conduction

    Science.gov (United States)

    Gudbjerg, J.; Sonnenborg, T. O.; Jensen, K. H.

    2004-08-01

    Previous experimental studies have shown that NAPL will be removed when it is contacted by steam. However, in full-scale operations, steam may not contact the NAPL directly and this is the situation addressed in this study. A two-dimensional intermediate scale sand box experiment was performed where an organic contaminant was emplaced below the water table at the interface between a coarse and a fine sand layer. Steam was injected above the water table and after an initial heating period the contaminant was recovered at the outlet. The experiment was successfully modeled using the numerical code T2VOC and the dominant removal mechanism was identified to be heat conduction induced boiling of the separate phase contaminant. Subsequent numerical modeling showed that this mechanism was insensitive to the porous medium properties and that it could be evaluated by considering only one-dimensional heat conduction.

  9. Disposal of high-level nuclear waste above the water table in arid regions

    Energy Technology Data Exchange (ETDEWEB)

    Roseboom, E.H. Jr.

    1983-12-31

    Locating a repository in the unsaturated zone of arid regions eliminates or simplifies many of the technological problems involved in designing a repository for operation below the water table and predicting its performance. It also offers possible accessibility and ease of monitoring throughout the operational period and possible retrieval of waste long after. The risks inherent in such a repository appear to be no greater than in one located in the saturated zone; in fact, many aspects of such a repository`s performance will be much easier to predict and the uncertainties will be reduced correspondingly. A major new concern would be whether future climatic changes could produce significant consequences due to possible rise of the water table or increased flux of water through the repository. If spent fuel were used as a waste form, a second new concern would be the rates of escape of gaseous {sup 129}I and {sup 14}C to the atmosphere.

  10. Mitigation of greenhouse gas fluxes from cultivated organic soils by raised water table

    OpenAIRE

    Regina, Kristiina

    2010-01-01

    Cultivated organic soils are a remarkable source of greenhouse gases (GHG) in some countries and raised ground water table has been suggested as a mitigation measure on these soils. Drainage of the peat increases mineralization of the organic matter and causes high emissions of carbon dioxide (CO2) and nitrous oxide (N2O) while emissions of methane (CH4) are lowered compared to pristine peatlands. In countries with a large area of organic soils these GHG emissions can be remarkable. In ...

  11. Automated lab-scale visualization of the influence of water table transients on LNAPL source zone dynamics

    Science.gov (United States)

    SUN, S.; Herbert, A. W.; Rivett, M. O.

    2015-12-01

    For buoyant LNAPLs (Light Non-Aqueous Phase Liquids), fluctuating water table conditions significantly influence capillary-held mass above and below the water table and the quantity of mobile free product floating on the water table. Risks posed by such a dynamic LNAPL source zone vary over time as water tables oscillate from say tidal influences, seasonality or other anthropogenic influences. Whist LNAPL dynamics are evident at field scale, measurements of say LNAPL thickness variation in a well are not very revealing of the actual source zone dynamic nature and point to the importance of lab visualization and modelling studies. We report on the recently completed lab phase of our study in which 2-D sand tanks have been used to visualize hydrocarbon LNAPL redistribution under transient water table conditions, particularly cyclic oscillations. We have developed a fully automated system to: i) Program cyclic water table fluctuations via Raspberry PiTM based electronics; ii) Dynamically monitor the saturation distributions of all fluids (red-dyed-LNAPL, blue-dyed-water and air phase by difference) using high temporal frequency and spatial resolution multi-spectral photography; and iii) Efficiently interpret the imaged data produced via multi-spectral image analysis. Such automated data acquisition and processing has permitted the LNAPL release and its redistribution under oscillating water table conditions to be shown in vivid short video formats of original images and contoured fluid saturations. We present a series of these videos secured under a variety of sand-tank scenarios that aim to understand the controlling influences of fluctuation amplitude and frequency, the influence of lower permeability heterogeneities, and the significance of LNAPL release timing relative to water table position. Our preliminary interpretations of these data will be presented alongside our discussion of the implications for characterization and remediation of LNAPL contaminated sites

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

    Science.gov (United States)

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

    2016-01-01

    Detailed monitoring of the groundwater table can provide important data about both short- and long-term aquifer processes, including information useful for estimating recharge and facilitating groundwater modeling and remediation efforts. In this paper, we presents results of 4 years (2002 to 2005) of monitoring groundwater water levels in the Rio Claro Aquifer using observation wells drilled at the Rio Claro campus of São Paulo State University in Brazil. The data were used to follow natural periodic fluctuations in the water table, specifically those resulting from earth tides and seasonal recharge cycles. Statistical analyses included methods of time-series analysis using Fourier analysis, cross-correlation, and R/S analysis. Relationships could be established between rainfall and well recovery, as well as the persistence and degree of autocorrelation of the water table variations. We further used numerical solutions of the Richards equation to obtain estimates of the recharge rate and seasonable groundwater fluctuations. Seasonable soil moisture transit times through the vadose zone obtained with the numerical solution were very close to those obtained with the cross-correlation analysis. We also employed a little-used deep drainage boundary condition to obtain estimates of seasonable water table fluctuations, which were found to be consistent with observed transient groundwater levels during the period of study.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-06-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Alphonce Chenjerayi GUZHA; Thomas Byron HARDY

    2010-01-01

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

  15. Numerical understanding of regional scale water table behavior in the Guadalupe Valley aquifer, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    J. R. Campos-Gaytan

    2006-05-01

    Full Text Available A regional groundwater flow model was developed, in order to evaluate the water table behavior in the region of the Guadalupe Valley, in Baja California, Mexico. The State of Baja California has been subject to an increment of the agricultural, urban and industrials activities, implicating a growing water-demand. However, the State is characterized by its semi-arid climate with low surface water availability; resulting in an extensive use of groundwater in local aquifer. Based on historic piezometric information of the last two decades, however, a negative evolution could be observed, resulting a negative storage volume. So far, there is not an integral hydrogeological evaluation that determine the real condition of the groundwater resource, and that permit to planning a management of the Guadalupe Valley Aquifer. A steady-state calibration model was carried out in order to obtain the best possible match to measured levels at the Guadalupe Valley Aquifer. The contours of calculated water table elevations for January 1983 were reproduced. Generally, the comparison of the observed and calculated water table configurations have a good qualitative and quantitatively adjustment. Nowadays, it is count with a hydrogeological model that can be used for simulates the groundwater flow in the region of the Guadalupe Valley.

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

    Directory of Open Access Journals (Sweden)

    M. H. Ali

    2013-11-01

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

  17. Sulfuric acid speleogenesis (SAS) close to the water table: Examples from southern France, Austria, and Sicily

    Science.gov (United States)

    De Waele, Jo; Audra, Philippe; Madonia, Giuliana; Vattano, Marco; Plan, Lukas; D'Angeli, Ilenia M.; Bigot, Jean-Yves; Anoux, Catherine; Nobécourt, Jean-Claude

    2016-01-01

    Caves formed by rising sulfuric waters have been described from all over the world in a wide variety of climate settings, from arid regions to mid-latitude and alpine areas. H2S is generally formed at depth by reduction of sulfates in the presence of hydrocarbons and is transported in solution through the deep aquifers. In tectonically disturbed areas major fractures eventually allow these H2S-bearing fluids to rise to the surface where oxidation processes can become active producing sulfuric acid. This extremely strong acid reacts with the carbonate bedrock creating caves, some of which are among the largest and most spectacular in the world. Production of sulfuric acid mostly occurs at or close to the water table but also in subaerial conditions in moisture films and droplets in the cave environment. These caves are generated at or immediately above the water table, where condensation-corrosion processes are dominant, creating a set of characteristic meso- and micromorphologies. Due to their close connection to the base level, these caves can also precisely record past hydrological and geomorphological settings. Certain authigenic cave minerals, produced during the sulfuric acid speleogenesis (SAS) phase, allow determination of the exact timing of speleogenesis. This paper deals with the morphological, geochemical and mineralogical description of four very typical sulfuric acid water table caves in Europe: the Grotte du Chat in the southern French Alps, the Acqua Fitusa Cave in Sicily (Italy), and the Bad Deutsch Altenburg and Kraushöhle caves in Austria.

  18. Water table effects on measured and simulated fluxes in weighing lysimeters for differently-textured soils

    Directory of Open Access Journals (Sweden)

    Wegehenkel Martin

    2015-03-01

    Full Text Available Weighing lysimeters can be used for studying the soil water balance and to analyse evapotranspiration (ET. However, not clear was the impact of the bottom boundary condition on lysimeter results and soil water movement. The objective was to analyse bottom boundary effects on the soil water balance. This analysis was carried out for lysimeters filled with fine- and coarse-textured soil monoliths by comparing simulated and measured data for lysimeters with a higher and a lower water table. The eight weighable lysimeters had a 1 m2 grass-covered surface and a depth of 1.5 m. The lysimeters contained four intact monoliths extracted from a sandy soil and four from a soil with a silty-clay texture. For two lysimeters of each soil, constant water tables were imposed at 135 cm and 210 cm depths. Evapotranspiration, change in soil water storage, and groundwater recharge were simulated for a 3-year period (1996 to 1998 using the Hydrus-1D software. Input data consisted of measured weather data and crop model-based simulated evaporation and transpiration. Snow cover and heat transport were simulated based on measured soil temperatures. Soil hydraulic parameter sets were estimated (i from soil core data and (ii based on texture data using ROSETTA pedotransfer approach. Simulated and measured outflow rates from the sandy soil matched for both parameter sets. For the sand lysimeters with the higher water table, only fast peak flow events observed on May 4, 1996 were not simulated adequately mainly because of differences between simulated and measured soil water storage caused by ET-induced soil water storage depletion. For the silty-clay soil, the simulations using the soil hydraulic parameters from retention data (i were matching the lysimeter data except for the observed peak flows on May, 4, 1996, which here probably resulted from preferential flow. The higher water table at the lysimeter bottom resulted in higher drainage in comparison with the lysimeters

  19. Map Plant Communities & Influence of Annual Water Table Fluctuations on Successional Expression: Malheur NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The 2012 Malheur NWR CCP identified the development of an ecological succession model (State-and-Transition Model, or STM) as a high priority for understanding how...

  20. Groundwater-soil moisture-climate interactions: lessons from idealized model experiments with forced water table depth

    Science.gov (United States)

    Ducharne, Agnès; Lo, Min-Hui; Decharme, Bertrand; Wang, Fuxing; Cheruy, Frédérique; Ghattas, Josefine; Chien, Rong-You; lan, Chia-Wei; Colin, Jeanne; Tyteca, Sophie

    2016-04-01

    Groundwater (GW) constitutes by far the largest volume of liquid freshwater on Earth. The most active part is soil moisture (SM), recognized as a key variable of land/atmosphere interactions, especially in so-called transition zones, where/when SM varies between wet and dry values. But GW can also be stored in deeper reservoirs than soils, in particular unconfined aquifer systems, in which the saturated part is called the water table (WT). The latter is characterized by slow and mostly horizontal water flows towards the river network, with well-known buffering effects on streamflow variability. Where/when the WT is shallow enough, it can also sustain SM by means of capillary rise, thus increase evapotranspiration (ET), with potential impact on the climate system (including temperatures and precipitation). The large residence time of GW may also increase the Earth system's memory, with consequences on the persistence of extreme events, hydro-climatic predictability, and anthropogenic climate change, particularly the magnitude of regional warming. Here, our main goal is to explore the potential impacts of the water table depth (WTD) on historical climate through idealized model analyses. To this end, we force three state-of-the art land surface models (LSMs), namely CLM, ORCHIDEE, and SURFEX, with prescribed WTDs ranging from 0.5 to 10 m. The LSMs are run either off-line or coupled to their parent climate model, following LMIP/AMIP-like protocols for intercomparability. Within this framework, we want to assess the sensitivity of ET and the simulated climate to the WTD in a systematic way. In particular, we will identify and compare the patterns of the critical WTD, defined as the deepest one to achieve a significant change in ET. To this end, we estimate derivatives of ET with respect to WTD, which tell how the sensitivity of ET to a unit change in WTD evolves with WTD. In each grid-point, these derivatives can be used to define the critical WTD, given a threshold ET

  1. Linking Water Table Dynamics to Carbon Cycling in Artificial Soil Column Incubations

    Science.gov (United States)

    Geertje, Pronk; Adrian, Mellage; Tatjana, Milojevic; Fereidoun, Rezanezhad; Cappellen Philippe, Van

    2016-04-01

    The biogeochemistry of wetlands soils is closely tied to their hydrology. Water table fluctuations that cause flooding and drying of these systems may lead to enhanced degradation of organic matter and release of greenhouse gasses (e.g. CO2, CH4) to the atmosphere. However, predicting the influence of water table fluctuations on the biogeochemical functioning of soils requires an understanding of the interactions of soil hydrology with biogeochemical and microbial processes. To determine the effects of water table dynamics on carbon cycling, we are carrying out state-of-the-art automated soil column experiments with fully integrated monitoring of hydro-bio-geophysical process variables under both constant and oscillating water table conditions. An artificial, homogeneous mixture consisting of minerals and organic matter is used to provide a well-defined starting material. The artificial soils are composed of quartz sand, montmorillonite, goethite and humus from a forested riparian zone, from which we also extracted the microbial inoculum added to the soil mixture. The artificial soils are packed into 60 cm high, 7.5 cm wide columns. In the currently ongoing experiment, three replicate columns are incubated while keeping the water table constant water at mid-depth, while another three columns alternate between drained and saturated conditions. Micro-sensors installed at different depths below the soil surface record time-series redox potentials (Eh) varying between oxidizing (~+700 mV) and reducing (~-200 mV) conditions. Continuous O2 levels throughout the soil columns are monitored using high-resolution, luminescence-based, Multi Fiber Optode (MuFO) microsensors. Pore waters are collected periodically with MicroRhizon samplers from different depths, and analyzed for pH, EC, dissolved inorganic and organic carbon and ion/cation compositions. These measurements allow us to track the changes in pore water geochemistry and relate them to differences in carbon cycling

  2. Methodologies of preparing erosion features map by using RS and GIS

    Institute of Scientific and Technical Information of China (English)

    Mohammadi Torkashvand Ali; Nikkami,Davood

    2008-01-01

    The erosion features map is one of the basic maps in erosion and sediment studies and watershed management programs.Some methodologies of preparing erosion features map by using RS and GIS were compared in research which took place in the Jajrood sub-basin in north-east Tehran,Iran.In the first phase,four working units' maps were prepared by integration a) plant cover,geology and slope b)land use,geology and slope c) land use,rocks sensitivity to erosion and slope and d) land use,rocks sensitivity to erosion and land units' layers.In addition to these four working units' maps,three more maps were also evaluated in separating erosion features including e) land units f) sensitivity of rocks to erosion and g) image photomorphic units.The efficiency of these seven working units' maps was evaluated by 314 control points.For this purpose,by using erosion features of control points regarding field views,surface,rill,gully and channel erosion maps were prepared and compared by crossing them with working units' maps.Results showed that method "d" was better than "a","b" and "c" in providing soil erosion features regarding economic and executive considerations.The accuracy of methods "e"and "f" was 53.0 and 42.9% and their Root Mean Squared Error was more than method "g" and methods "a" to "d".The coefficient of variation was highest for methods "e" and "f" and the least for method "e" and the greatest precision was related to image interpretation.

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

    Science.gov (United States)

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

    2014-12-01

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

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

    Directory of Open Access Journals (Sweden)

    AC. Silva

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

  5. Potential of Ground Penetrating Radar for the characterization of the shallow water table in the Mnasra region in Morocco

    Directory of Open Access Journals (Sweden)

    Imane SEBARI

    2016-03-01

    Full Text Available Morocco is a water-scarce country confronted with a severe dependence on rain-fed agriculture and dwindling groundwater reserves. Since 1995, new water regulation laws and management strategies have been promulgated providing a comprehensive framework for an integrated management. Moreover, water managers should have precise data on the current state of water tables depth in strategic aquifers. Unfortunately, the main source of these data are sporadic wells with no automated monitoring systems making the assessment of water table dynamics, costly, time consuming and out-phased with decision maker needs. In this respect, this paper focuses on the capability of Ground Penetrating Radar to determine the depth of shallow water table in Mnasra region, located in the Gharb region of Morocco as a pilot study to generalize its use in the future for groundwater dynamic monitoring purposes in Morocco. The experiment was undertaken using Mala 800 MHz shielded antennas and was able to probe the depth of the upper fresh water table at 3.75 m deep in the Mnasra aquifer in semi-arid conditions. Data collected by GPR can be used as substitute for well logs to enhance the monitoring of water tables in stressed areas during droughts and excessive recharges during rainy season.

  6. Non-Markovian memory in quantum process tomography and a preparation independent map

    CERN Document Server

    Modi, Kavan

    2010-01-01

    Recently it has been pointed out how differences in preparation procedures for quantum experiments can lead to non-trivial differences in the results of the experiment. The difference arise from the initial correlations between the system and environment. Therefore, any quantum experiment that is prone to the influences from the environment must be prepared carefully. In this paper, we study a quantum process tomography procedure that yields a result independent of the preparation procedure. We investigate the properties of this map and find an approach to distinguish the role of initial correlation in the dynamics of the system.

  7. Water-table and potentiometric-surface altitudes in the Upper Glacial, Magothy, and Lloyd aquifers of Long Island, New York, April-May 2013

    Science.gov (United States)

    Como, Michael D.; Noll, Michael L.; Finkelstein, Jason S.; Monti, Jack; Busciolano, Ronald

    2015-01-01

    The U.S. Geological Survey (USGS), in cooperation with State and local agencies, systematically collects groundwater data at varying measurement frequencies to monitor the hydrologic conditions on Long Island, New York. Each year during April and May, the USGS conducts a synoptic survey of water levels to define the spatial distribution of the water table and potentiometric surfaces within the three main water-bearing units underlying Long Island—the upper glacial, Magothy, and Lloyd aquifers (Smolensky and others, 1989)—and the hydraulically connected Jameco (Soren, 1971) and North Shore aquifers (Stumm, 2001). These data and the maps constructed from them are commonly used in studies of Long Island's hydrology and are utilized by water managers and suppliers for aquifer management and planning purposes.

  8. Remediation of an Organic Fluid Present Below the Water Table by Steam Injection Above

    Science.gov (United States)

    Gudbjerg, J.; Jensen, K. H.; Sonnenborg, T. O.

    2001-12-01

    Injection of steam in the subsurface has been utilized to remediate contaminated sites where nonaqeuous phase liquid (NAPL) was present both above and below the water table. Steam injection is efficient because the vapor pressure of contaminants increase dramatically with temperature. Futhermore, since two immiscible liquids will boil when the sum of their vapor pressures is equal to the surrounding pressure all NAPLs will start to boil below the boiling point of water. This may be a dominant mechanism for the mass transfer of NAPL into the steam zone. In many cases a steady-state steam zone will be present above a saturated zone containing NAPL, which then will be heated by conduction. At a certain temperature boiling will occur and due to bouyancy gas will be transported from the saturated zone into the steam zone. This mass transfer mechanism is orders of magnitude faster than diffusionevaporation. Two-dimensional experiments in a sand box with the interior dimensions 122 \\times 58 \\times 8.5 cm were carried out to investigate this mechanism. The sand box was packed with a low permeable bottom layer and a high permeable top layer. TCE was injected at the top of the low permeable layer, which prevented it from further downward migration. The water table was located in the high permeable layer above the contaminant. Steam was injected in the left hand side of the sand box and effluent gasses were extracted at the right hand side. A steady-state steam zone formed in the top of the high permeable layer and the saturated zone below was only heated by conduction. When the temperature in the contaminated area reached approximately 74 oC boiling of TCE and water occured and the vapors were transported up in the unsaturated steam zone. This could be registered from the outflow of steam where separate phase TCE appeared in the condenser. The experiment was modeled using the numerical code T2VOC, which simulates multidimensional, non-isothermal, multiphase flow and

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

    DEFF Research Database (Denmark)

    Faubert, P; Tiiva, P; Nakam, TA

    2011-01-01

    BVOC groups. Only isoprene emission was significantly increased by warming, parallel to the increased leaf number of the dominant sedge Eriophorum vaginatum. BVOC emissions from peat soil were higher under the control and warming treatments than water table drawdown, suggesting an increased activity...... assessed the combined effect of warming and water table drawdown on the BVOC emissions from boreal peatland microcosms. We also assessed the treatment effects on the BVOC emissions from the peat soil after the 7-week long experiment. Emissions of isoprene, monoterpenes, sesquiterpenes, other reactive VOCs...... and other VOCs were sampled using a conventional chamber technique, collected on adsorbent and analyzed by GC–MS. Carbon emitted as BVOCs was less than 1% of the CO2 uptake and up to 3% of CH4 emission. Water table drawdown surpassed the direct warming effect and significantly decreased the emissions of all...

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    in water content, a controlled experiment was set up in 30 m by 20 m basin. The water table was lowered 0.69 m within 1½ hours and the corresponding gravity signal measured using two different approaches: a time series measurements at one location and a gravity network measurement including four points....... Both where in agreement with the calculated maximum theoretical gravity change of 27*10^-8 m/s^2. Uncertainties on the change in gravity in the network measurements where 4*10^-8 m/s^2 (one standard deviation). This corresponds to an infinite horizontal slab of water with a thickness of 0.1 m. The time...

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    Gravity changes linearly with the change in soil water content. With the GRACE satellite mission the interest for ground-based gravity methods in hydrology has gained new attention. Time-lapse gravity data have the potential to constrain hydrological model parameters in a calibration scheme...... in water content, a controlled experiment was set up in 30 m by 20 m basin. The water table was lowered 0.69 m within 1½ hours and the corresponding gravity signal measured using two different approaches: a time series measurements at one location and a gravity network measurement including four points....... Both where in agreement with the calculated maximum theoretical gravity change of 27*10^-8 m/s^2. Uncertainties on the change in gravity in the network measurements where 4*10^-8 m/s^2 (one standard deviation). This corresponds to an infinite horizontal slab of water with a thickness of 0.1 m. The time...

  12. Geophysical Contribution in the Characterization of Deep Water Tables Geometry (Sidi Bouzid, Central Tunisia

    Directory of Open Access Journals (Sweden)

    D. Khazri

    2015-01-01

    Full Text Available Geophysical data combined with geological and hydrogeological data were analyzed to characterize the geometry of Oued El Hajel and Ouled Asker deep water tables (Sidi Bouzid. The obtained results allowed refining the geostructural schema by highlighting the individualization of the NE-SW underground convexity of Ouled Asker and the anticline of axis Es Souda-Hmaeima and Ezaouia on either sides of two hydrogeological thresholds. The geometrical analysis determined the spatial extension of Ouled Asker and Oued El Hajel subbasins. The seismic cartography of semideep and deep reservoirs (Oligo-Miocene; Eocene and upper Cretaceous associated with the main subbasins contributed to proposing hydrogeological prospect zones for a rationalized groundwater exploitation.

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

    Science.gov (United States)

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

    2017-06-01

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

  14. DEVELOPMENT OF SORGHUM PLANTS SUBMITTED UNDER DIFFERENT WATER TABLE LEVELS IN GLASSHOUSE

    Directory of Open Access Journals (Sweden)

    Adriana Aki Tanaka

    2014-03-01

    Full Text Available DESENVOLVIMENTO DE PLANTAS DE SORGO SUBMETIDAS A DIFERENTES NÍVEIS DE LENÇOL FREÁTICO EM CASA DE VEGETAÇÃO O objetivo deste trabalho foi avaliar o desenvolvimento das plantas de sorgo (Sorghum bicolor L. Moench submetidas a diferentes níveis de lençol freático. O projeto foi realizado em casa de vegetação de vidro, sobre bandejas com reservatórios de água que permitiam a subirrigação e vasos constituídos de tubos de PVC (15 cm de diâmetro com diferentes alturas simulando diferentes níveis de lençol freático com cinco profundidades (0,17 m; 0,31 m; 0,45 m; 0,59 m; 0,73 m, tratamentos T1; T2; T3; T4; T5 e T6 respectivamente, em delineamento inteiramente casualizado. Os parâmetros analisados foram: massa da matéria fresca e seca, altura e diâmetro do colmo das plantas; massa da matéria fresca e seca e comprimento das panículas; massa da matéria seca das raízes total; área foliar; número de folhas; evapotranspiração da cultura (ETc; coeficiente da cultura (Kc. T3 e T4 foram os melhores, apresentando os maiores valores para ambas as massas, fresca e seca. Para as panículas, os maiores valores para as massas de matéria fresca e seca e comprimento foram apresentados por T4 e T5. Para o diâmetro do colmo não houve significância estatística entre T3, T4 e T5. Plantas cultivadas em níveis freáticos mais próximos da superfície induziram a produção de colmos mais grossos. Palavras-chave: características agronômicas, evapotranspiração, coeficiente da cultura. ABSTRACT This study aimed to evaluate the sorghum plants development (Sorghum bicolor L. Moench submitted to different water table levels. The experiment was carried out in a glasshouse on trays with water reservoirs that allowed sub irrigation, and PVC tubes (15 cm diameter with different heights simulating five water table levels (17 cm; 31 cm; 45 cm; 59 cm; 73 cm, treatments T1; T2; T3; T4; T5 respectively, in an entirely random design. The analyzed

  15. CO2 phase mutation by fluctuating water table in the vadose zone over a CCS site

    Science.gov (United States)

    Joun, W.; Ha, S. W.; Kim, H. H.; Kim, T. W.; Lee, S. S.; Lee, K. K.

    2015-12-01

    Geological sequestration of carbon dioxide (CO2) is one of the feasible plans to control greenhouse gas emissions. In order to be more perfect, the plan has to prove that the injected CO2 gas will not be leaking. Even if CO2 leaking happens, we should possess a technique which provides information on specific aquifer system before critical effect to ground and subsurface environments. Many parameters have been utilized for early detection before risk to environments by sensing CO2 gas concentration, electric conductivity, pH, and ion analysis. However, these are not enough to all CCS sites for leakage detection. For example, the importance of gas leaking path is emphasized because finding the dominant gas flow path can reduce risk and provide a quick estimation. Herein, we investigate dissolved solute degassing and vertical flow from saturated zone to unsaturated zone in shallow depth aquifer. Especially we focused on the water table fluctuation effect. Based on field data and basic parameters, we perform a pilot scale gas injection test and calculate gas flow saturation with STOMP simulator. The CO2 gas concentrations at different depth levels according to amount of injected CO2 infused water, CO2 gas saturation in vadose zone have different concentration values. If we estimate this phenomenon in vadose zone by using CO2 gas detection method, we could presume that the CO2 dissolved in shallow groundwater is degassing and flow upward into vadose zone. However, the concentration level and change patterns are not same and will be changed according to the pattern of water table fluctuation. This study could be usefully applied to strategic CCS environmental monitoring of CO2 leakage.Acknowledgement: Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003).

  16. Numerical analysis of a three-phase system with a fluctuating water table

    Energy Technology Data Exchange (ETDEWEB)

    White, M.D.; Lenhard, R.J.

    1993-03-01

    Numerical simulations are presented of a one-dimensional, multiphase flow system that involves the redistribution of aqueous-phase liquids and nonaqueous-phase liquids (NAPLs) by a fluctuating water table. The numerical analyses were completed using an integrated-volume, finite-difference-based solution scheme of the governing multiphase conservation equations and constitutive theory. Conservation equations were solved for two components water and oil, with the assumption of a passive gas-phase. Nonlinearities introduced into the governing conservation equations through the constitutive theory were handled with a multivariable Newton-Raphson iterative scheme. The functional relationships between the phase relative permeability, the phase saturation, and phase pressures in porous media were described with a general theoretical model that includes the effects of air and oil occlusion during imbibition. Parameters required for the theoretical model were defined for two-phase systems (e.g., air- water, air-oil, and oil-water). The theoretical model assumes that wettability decreases in the following order: water, oil, air. Results from the numerical simulations are compared against measurements taken from a previous multiphase flow experiment. The experiment involved subjecting an initially water-drained, three-phase system (i.e., air-oil-water), to a fluctuating water table. The experimental objective was to quantify the entrapment of air and NAPL by phases of greater wettability under dynamic conditions. Comparison of numerical and experimental results were made for two ratios of imbibition to drainage characteristic, curve-shape parameters and two models for relative permeability in two-phase systems. A description of the numerical methods used to solve the governing conservation and constitutive equations for multiphase hysteretic conditions is given.

  17. Rotating water table for the determination of non-steady forces in a turbine stage through modified hydraulic analogy

    Science.gov (United States)

    Rao, J. S.; Raghavacharyulu, E.; Seshadri, V.; Rao, V. V. R.

    1983-10-01

    Determination of non-steady forces in a real turbine stage is difficult due to the local flow conditions, for example high pressures, high temperatures and in-accessibility to the region etc. Experimentation in a real turbine is also prohibitive due to the costs involved. An alternate method of arriving at these non-steady forces through the use of modified hydraulic analogy is discussed. A rotating water table facility, developed and fabricated based on the principles of modified hydraulic analogy is described. A flat plate stage is simulated on the rotating water table, and the results obtained are presented.

  18. Rotating Water Table for the Determination of Non-Steady Forces in a Turbine Stage Through Modified Hydraulic Analogy

    Directory of Open Access Journals (Sweden)

    J. S. Rao

    1983-10-01

    Full Text Available Determination of non-steady forces in a real turbine stage is difficult due to the local flow conditions, for example high pressures, high temperatures and in-accessibility to the region etc. Experimentation in a real turbine is also prohibitive due to the costs involved. An alternate method of arriving at these non-steady forces through the use of modified hydraulic analogy is discussed. A rotating water table facility, developed and fabricated based on the principles of modified hydraulic analogy ia described. A flat plate stage is simulated on the rotating water table, and the results obtalned are presented.

  19. Participatory three dimensional mapping for the preparation of landslide disaster risk reduction program

    Science.gov (United States)

    Kusratmoko, Eko; Wibowo, Adi; Cholid, Sofyan; Pin, Tjiong Giok

    2017-07-01

    This paper presents the results of applications of participatory three dimensional mapping (P3DM) method for fqcilitating the people of Cibanteng' village to compile a landslide disaster risk reduction program. Physical factors, as high rainfall, topography, geology and land use, and coupled with the condition of demographic and social-economic factors, make up the Cibanteng region highly susceptible to landslides. During the years 2013-2014 has happened 2 times landslides which caused economic losses, as a result of damage to homes and farmland. Participatory mapping is one part of the activities of community-based disaster risk reduction (CBDRR)), because of the involvement of local communities is a prerequisite for sustainable disaster risk reduction. In this activity, participatory mapping method are done in two ways, namely participatory two-dimensional mapping (P2DM) with a focus on mapping of disaster areas and participatory three-dimensional mapping (P3DM) with a focus on the entire territory of the village. Based on the results P3DM, the ability of the communities in understanding the village environment spatially well-tested and honed, so as to facilitate the preparation of the CBDRR programs. Furthermore, the P3DM method can be applied to another disaster areas, due to it becomes a medium of effective dialogue between all levels of involved communities.

  20. Application Of Water Table Fluctuation Method To Quantify Spatial Groundwater Recharge Witidn The Southern Slope Of Merapi Volcano, Indonesia

    Directory of Open Access Journals (Sweden)

    Tjahyo Nugroho Adji

    2013-07-01

    that results in groundwater recharge characteristic. The volcanic slope unit (above 600 m as! has the lowest water table fluctuation indicates the resistant comportment to the annual rainfall. Ihis unit is characterized by the relatively high magnitude of recharge of approximately 4270 mm/year.

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

    Science.gov (United States)

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

    2017-01-01

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

  2. Space-time modeling of water table depth using a regionalized time series model and the Kalman filter

    NARCIS (Netherlands)

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

    2001-01-01

    Water authorities in the Netherlands are not only responsible for managing surface water, but also for managing the groundwater reserves. Particularly the water table depth is an important variable, determining agricultural production and the potential for nature development. Knowledge of the spatio

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

    Directory of Open Access Journals (Sweden)

    C. Gascuel-Odoux

    2009-11-01

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

  4. Method of teaching reading of map of orientation-sportsmen's on the stage of initial preparation

    Directory of Open Access Journals (Sweden)

    Furman Yu.N.

    2010-04-01

    Full Text Available Directions of development and perfection of major skill are rotined in the system of technical preparation of sportsman - to reading of map. Basic exercises are resulted on teaching of beginnings sportsmen. Exercises are directed on development of memory, attention, operative thought of young sportsmen. Tasks are presented on locality and in a class. Basic tasks are selected creatively going of trainer near the work. Experience trainers and system of the individual going is grounded near teaching of sportsman.

  5. Preparation of magnetic anomaly profile and contour maps from DOE-NURE aerial survey data. Volume 1: Processing procedures

    Science.gov (United States)

    Tennel, E. P.; Hinze, W. J.

    1981-09-01

    Total intensity magnetic anomaly data acquired as a supplement to radiometric data in preparing regional profile and contour maps are discussed. Survey contractor supplied magnetic anomaly data are subjected to a multiprocess, computer based procedure. This procedure is used to produce the following machine plotted maps: (1) profile map of contractor supplied magnetic anomaly data; (2) profile map of high cut filtered data with contour levels of each profile marked and annotated on the associated flight track; (3) profile map of critical point data with contour levels indicated; and (4) contour map of filtered and selected data.

  6. Water-table height and microtopography control biogeochemical cycling in an Arctic coastal tundra ecosystem

    Science.gov (United States)

    Lipson, D. A.; Zona, D.; Raab, T. K.; Bozzolo, F.; Mauritz, M.; Oechel, W. C.

    2012-01-01

    Drained thaw lake basins (DTLB's) are the dominant land form of the Arctic Coastal Plain in northern Alaska. The presence of continuous permafrost prevents drainage and so water tables generally remain close to the soil surface, creating saturated, suboxic soil conditions. However, ice wedge polygons produce microtopographic variation in these landscapes, with raised areas such as polygon rims creating more oxic microenvironments. The peat soils in this ecosystem store large amounts of organic carbon which is vulnerable to loss as arctic regions continue to rapidly warm, and so there is great motivation to understand the controls over microbial activity in these complex landscapes. Here we report the effects of experimental flooding, along with seasonal and spatial variation in soil chemistry and microbial activity in a DTLB. The flooding treatment generally mirrored the effects of natural landscape variation in water-table height due to microtopography. The flooded portion of the basin had lower dissolved oxygen, lower oxidation-reduction potential (ORP) and higher pH, as did lower elevation areas throughout the entire basin. Similarly, soil pore water concentrations of organic carbon and aromatic compounds were higher in flooded and low elevation areas. Dissolved ferric iron (Fe(III)) concentrations were higher in low elevation areas and responded to the flooding treatment in low areas, only. The high concentrations of soluble Fe(III) in soil pore water were explained by the presence of siderophores, which were much more concentrated in low elevation areas. All the aforementioned variables were correlated, showing that Fe(III) is solubilized in response to anoxic conditions. Dissolved carbon dioxide (CO2) and methane (CH4) concentrations were higher in low elevation areas, but showed only subtle and/or seasonally dependent effects of flooding. In anaerobic laboratory incubations, more CH4 was produced by soils from low and flooded areas, whereas anaerobic CO2

  7. Possibility of Preparing Thematic Maps Through Developing of the Geographic Information System (GIS

    Directory of Open Access Journals (Sweden)

    Stjepan Husnjak

    2013-04-01

    Full Text Available It is a well known fact that nowadays planning of sustainable development and land use requires a lot of reliable and good quality information, which serves as the basis for timely and adequate decision-making. One of the most important forms of information is presented in various maps. Until recently, preparing of such data was, no doubt, a rather complex and time-consuming task. However, at present, thanks to, first of all, the GIS technology it is possible to develop corresponding geographic information systems with databases which then allow comparatively simple and quick preparing of necessary thematic maps. The paper first presents the method of developing the Geographic and Land Information System (GLIS of the Karlovac County which, although developed for the purpose of agricultural development, may also be used in the development of forestry, environment protection, physical planning, water management and for soil conservation and regulation. Several examples illustrate the possibilities of preparing of specialised maps based on this GLIS. The basic data for developing of the geographic and land information system were the data of the Basic Soil Maps and topographic maps of the Republic of Croatia at the scale of 1:50 000 or 1:25 000, and the data from other studies made for the purpose of agricultural development in the area. These data, together with the results of processing and analysing of this data, by digitalisation, generalisation and interpolation, were incorporated into an integrated database of the geographic and land information system by using Microstation, AutoCad, ArcInfo, ArcWiew and Access software and the corresponding hardware. GLIS database consists of two parts. The first part includes the data referring to polygons - pedological contours, and the other part the data on pedological profiles. The base is organised in a way that enable the preparation of different thematic maps, but it can be also used in digital form

  8. A novel automated fluctuating water table column system to study redox oscillations in saturated and unsaturated media

    Science.gov (United States)

    Rezanezhad, F.; Couture, R.-M.; Kovac, R.; Van Cappellen, P.

    2012-04-01

    An automated, computer-controlled soil column experimental setup was developed to simulate in detail the effects of water table dynamics on the biogeochemical transformations of nutrients and other redox-sensitive chemical species at the interface between groundwater and surface waters. The experiments were conducted using two parallel soil columns, one under stable and the other under fluctuating water table conditions. The water table in the soil columns was controlled by an automated multi-channel pump connected to two equilibrium and storage columns. In the stable column, the water table was maintained at -20 cm below the soil surface while it fluctuated between the soil surface and -45 cm in the fluctuating column at a rate of 4.8 cm/d. Redox potential (Eh), pH profiles were measured continuously using high temporal resolution microsensors (10 μm glass tip) installed into the columns at different depths. The results show striking geochemical contrasts between the fluctuating and the stable columns, demonstrating that the setup is able to impose redox potential oscillations ranging from oxidizing (~+700 mv) to reducing (~-200 mv) conditions. CO2 fluxes were monitored in the headspace above the soil surface using a LICOR LI-8100 automated soil CO2 flux system. The mean CO2 emission in the stable water table column was ~20 ppm/min. In the fluctuating soil column, the CO2 flux varied between 4 and 110 ppm/min and the lowest were measured at the highest water level. Water samples obtained from micro-Rhizon samplers installed into the columns at various depths. Additionally, the physical, chemical and microbial characteristics of the media were characterized by centimetre scale slicing of the soil columns at the end of the experiment. The impacting of these oscillations on the distribution of chemical species will be discussed in term of the interactions between soils, solutes, microbial activity, and hydrology.

  9. Overriding control of methane flux temporal variability by water table dynamics in a Southern Hemisphere, raised bog

    Science.gov (United States)

    Goodrich, J. P.; Campbell, D. I.; Roulet, N. T.; Clearwater, M. J.; Schipper, L. A.

    2015-05-01

    There are still large uncertainties in peatland methane flux dynamics and insufficient understanding of how biogeochemical processes scale to ecosystems. New Zealand bogs differ from Northern Hemisphere ombrotrophic systems in climatic setting, hydrology, and dominant vegetation, offering an opportunity to evaluate our knowledge of peatland methane biogeochemistry gained primarily from northern bogs and fens. We report eddy covariance methane fluxes from a raised bog in New Zealand over 2.5 years. Annual total methane flux in 2012 was 29.1 g CH4 m-2 yr-1, whereas during a year with a severe drought (2013) it was 20.6 g CH4 m-2 yr-1, both high compared to Northern Hemisphere bogs and fens. Drier conditions led to a decrease in fluxes from ~100 mg CH4 m-2 d-1 to ~20 mg CH4 m-2 d-1, and subsequent slow recovery of flux after postdrought water table rise. Water table depth regulated the temperature sensitivity of methane fluxes, and this sensitivity was greatest when the water table was within 100 mm of the surface, corresponding to the shallow rooting zone of the dominant vegetation. A correlation between daytime CO2 uptake and methane fluxes emerged during times with shallow water tables, suggesting that controls on methane production were critical in determining fluxes, more so than oxidation. Water table recession through this shallow zone led to increasing methane fluxes, whereas changes in temperature during these periods were not correlated. Models of methane fluxes should consider drought-induced lags in seasonal flux recovery that depend on drought characteristics and location of the critical zone for methane production.

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

    Science.gov (United States)

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

    2005-05-01

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

  11. The role of sustained water table drawdown and wildfire on C emissions in boreal peatlands

    Science.gov (United States)

    Kotowska, A.; Turetsky, M. R.; Benscoter, B.

    2011-12-01

    Northern peatlands store up to 370 Pg C, or ~80% of boreal soil carbon (C). In general, peat accumulates where water table (WT) levels at or near the soil surface lead to high primary productivity and low rates of decomposition. However, increased evapotranspiration under warmer, drier conditions predicted for boreal peatlands under future climate change are expected to decrease seasonal WT levels and increase the potential for deep peat fires. The effects of long-term changes in hydrology on northern peatland vegetation and C cycling are not well understood, nor are the effects of wildfire on interactions between C cycling and peatland hydrology. The objective of this study was to examine the net effects of fire and long-term water table drawdown on CO2 and CH4 fluxes. We utilized a rich fen impacted by road construction in the early 1990's and a bog that experienced a severe fire 4 years prior to study initiation to examine drought and fire disturbances, respectively. We found that 20 years of sustained WT drawdown had no effect on understory net ecosystem exchange (NEE) of CO2. However, WT drawdown did increase ecosystem respiration (ER) and gross primary productivity (GPP) relative to pristine plots. WT drawdown also altered the response of GPP to light availability and WT position, as well as the temperature sensitivity (Q10) of ER. Surprisingly, mean CH4 emissions did not change as a result of WT drawdown, though fewer ebullition events were observed in the drought plot. Four years post-fire, NEE was higher (net C sink) in the burned plot compared to the unburned (75 years since fire) plot. As expected, we found a negative relationship between ER and WT in the unburned plot, but this pattern was reversed in the burned plot, where ER was highest under relatively wet conditions. Despite lower plant cover in the burned plot, there were no differences in GPP between the sites, indicating high photosynthetic capacity in surviving and newly-colonizing vegetation

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

    Directory of Open Access Journals (Sweden)

    Xilin Lu

    2014-01-01

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

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

    Science.gov (United States)

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

    2011-08-01

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

  14. Slug tests in wells screened across the water table: some additional considerations.

    Science.gov (United States)

    Butler, J J

    2014-01-01

    The majority of slug tests done at sites of shallow groundwater contamination are performed in wells screened across the water table and are affected by mechanisms beyond those considered in the standard slug-test models. These additional mechanisms give rise to a number of practical issues that are yet to be fully resolved; four of these are addressed here. The wells in which slug tests are performed were rarely installed for that purpose, so the well design can result in problematic (small signal to noise ratio) test data. The suitability of a particular well design should thus always be assessed prior to field testing. In slug tests of short duration, it can be difficult to identify which portion of the test represents filter-pack drainage and which represents formation response; application of a mass balance can help confirm that test phases have been correctly identified. A key parameter required for all slug test models is the casing radius. However, in this setting, the effective casing radius (borehole radius corrected for filter-pack porosity), not the nominal well radius, is required; this effective radius is best estimated directly from test data. Finally, although conventional slug-test models do not consider filter-pack drainage, these models will yield reasonable hydraulic conductivity estimates when applied to the formation-response phase of a test from an appropriately developed well.

  15. Temperature Responses to Infrared-Loading and Water Table Manipulations in Peatland Mesocosms

    Institute of Scientific and Technical Information of China (English)

    Jiquan Chen; Scott Bridgham; Jason Keller; John Pastor; Asko Noormets1and; F. Weltzin

    2008-01-01

    We initiated a multi-factor global change experiment to explore the effects of infrared heat loading (HT) and water table level (WL) treatment on soil temperature (T) in bog and fen peatland mesocosms. We found that the temperature varied highly by year, month, peatland type, soil depth, HT and WL manipulations. The highest effect of HT on the temperature at 25 cm depth was found in June for the bog mesocosms (3.34-4.27℃) but in May for the fen mesocosms (2.32-4.33℃) over the 2-year study period. The effects of WL in the bog mesocosms were only found between August and January, with the wet mesocosms warmer than the dry mesocosms by 0.48-2.03 ℃ over the 2-year study period. In contrast, wetter fen mesocoams were generally cooler by 0.16-3.87℃. Seasonal changes of temperatures elevated by the HT also varied by depth and ecosystem type, with temperature differences at 5 cm and 10 cm depth showing smaller seasonal fluctuations than those at 25 cm and 40 cm in the bog mesocosrns. However, increased HT did not always lead to warmer soil, especially in the fen mesocosms. Both HT and WL manipulations have also changed the length of the non-frozen season.

  16. Coupling water table fluctuation to mercury speciation and transport in wetland ecosystems

    Science.gov (United States)

    Branfireun, B. A.; Mitchell, C. P.

    2008-12-01

    Hydrological processes exert a first-order control over both the conditions required for mercury methylation to occur, and the transport of methylmercury from sites of production. In the recent literature, evidence has been presented that a relationship exists between water level fluctuation and mercury levels in aquatic organisms. These observations have led to the conclusion that this fluctuation is stimulating mercury methylation in littoral sediments and wetland ecosystems through the creation of favourable biogeochemical conditions. Using data from a range of wetland ecosystems, and several experiments that subjected wetland soils to fluctuating water levels, a relationship between water table fluctuation frequency and methylmercury production will be presented. Experimental data show that longer frequency wetting and drying periods result in greater methylmercury production relative to a static or high frequency fluctuation. It was also found that mercury methylation processes in wetland soils are able to sustain elevated pore water concentrations over repeated wetting and draining events. These data suggest that methylmercury export from wetlands is likely limited by the degree of hydrological connectivity rather than biogeochemical processes, highlighting the need to better understand the nature of hydrological linkages among wetlands and adjacent ecosystems.

  17. Effect of Perched Water Tables on Aluminosilicate Stability and Soil Genesis

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (> 10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the Inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability.

  18. Sea level and ground water table depth (WTD): A biogeochemical pacemaker for glacial-interglacial cycling

    Science.gov (United States)

    Cowling, S. A.

    2016-11-01

    The role that changes in sea level have on potential carbon-climate feedbacks are discussed as a potential contributing mechanism for terminating glacial periods. Focus will be on coastal wetlands because these systems can be substantially altered by changing sea level and ground water table depth (WTD); in addition to being important moderators of the exchange of nutrients and energy between terrestrial and marine ecosystems. A hypothesis is outlined that describes how the release of carbon from formerly anaerobic wetland soils and sediments can influence climate when sea levels begin to decline. As ground WTD deepens and eventually recedes from the surface, coastal wetland basins may become isolated from their belowground source of water. With their primary source of base flow removed, coastal wetlands likely dried up, promoting decomposition of the carbon compounds buried in their sediments. Depending on the timing of basin isolation and the timing of decomposition, glacial sea level lows could have triggered a relatively large positive carbon feedback on climate warming, just at the time when a new interglacial period is about to begin.

  19. Quantification of aerobic biodegradation and volatilization rates of gasoline hydrocarbons near the water table under natural attenuation conditions

    Science.gov (United States)

    Lahvis, M.A.; Baehr, A.L.; Baker, R.J.

    1999-01-01

    Aerobic biodegradation and volatilization near the water table constitute a coupled pathway that contributes significantly to the natural attenuation of hydrocarbons at gasoline spill sites. Rates of hydrocarbon biodegradation and volatilization were quantified by analyzing vapor transport in the unsaturated zone at a gasoline spill site in Beaufort, South Carolina. Aerobic biodegradation rates decreased with distance above the water table, ranging from 0.20 to 1.5g m-3 d-1 for toluene, from 0.24 to 0.38 g m-3 d-1 for xylene, from 0.09 to 0.24 g m-3 d-1 for cyclohexene, from 0.05 to 0.22 g m-3 d-1 for ethylbenzene, and from 0.02 to 0.08 g m-3 d-1 for benzene. Rates were highest in the capillary zone, where 68% of the total hydrocarbon mass that volatilized from the water table was estimated to have been biodegraded. Hydrocarbons were nearly completely degraded within 1 m above the water table. This large loss underscores the importance of aerobic biodegradation in limiting the transport of hydrocarbon vapors in the unsaturated zone and implies that vapor-plume migration to basements and other points of contact may only be significant if a source of free product is present. Furthermore, because transport of the hydrocarbon in the unsaturated zone can be limited relative to that of oxygen and carbon dioxide, soil, gas surveys conducted at hydrocarbon-spill sites would benefit by the inclusion of oxygen- and carbon-dioxide-gas concentration measurements. Aerobic degradation kinetics in the unsaturated zone were approximately first-order. First-order rate constants near the water table were highest for cyctohexene (0.21-0.65 d-1) and nearly equivalent for ethylbenzene (0.11-20.31 d-1), xylenes (0.10-0.31 d-1), toluene (0.09-0.30 d-1), and benzene (0.07,0.31 d-1). Hydrocarbon mass loss rates at the water table resulting from the coupled aerobic biodegradation and volatilization process were determined by extrapolating gas transport rates through the capillary zone. Mass

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

    Science.gov (United States)

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

    2012-12-01

    In many groundwater systems, the height of the water table must be above certain thresholds for some types of surface flow to exist. Examples of flows that depend on water table elevation include groundwater baseflow to river systems, groundwater flow to wetland systems, and flow to springs. Meeting many of the goals of sustainable water resource management requires maintaining these flows at certain rates. Water resource management decisions invariably involve weighing tradeoffs between different possible usage regimes and the economic consequences of potential management choices are an important factor in these tradeoffs. Policies based on sustainability may have a social cost from forgoing present income. This loss of income may be worth bearing, but should be well understood and carefully considered. Traditionally, the economic theory of groundwater exploitation has relied on the assumption of a single-cell or "bathtub" aquifer model, which offers a simple means to examine complex interactions between water user and hydrologic system behavior. However, such a model assumes a closed system and does not allow for the simulation of groundwater outflows that depend on water table elevation (e.g. baseflow, springs, wetlands), even though those outflows have value. We modify the traditional single-cell aquifer model by allowing for outflows when the water table is above certain threshold elevations. These thresholds behave similarly to holes in a bathtub, where the outflow is a positive function of the height of the water table above the threshold and the outflow is lost when the water table drops below the threshold. We find important economic consequences to this representation of the groundwater system. The economic value of services provided by threshold-dependent outflows (including non-market value), such as ecosystem services, can be incorporated. The value of services provided by these flows may warrant maintaining the water table at higher levels than would

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

    Directory of Open Access Journals (Sweden)

    Merjo P. P. Laine

    2013-01-01

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

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

    Science.gov (United States)

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

    2005-01-01

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

  3. Vertical radar profiles for the calibration of unsaturated flow models under dynamic water table conditions

    Science.gov (United States)

    Cassiani, G.; Gallotti, L.; Ventura, V.; Andreotti, G.

    2003-04-01

    The identification of flow and transport characteristics in the vadose zone is a fundamental step towards understanding the dynamics of contaminated sites and the resulting risk of groundwater pollution. Borehole radar has gained popularity for the monitoring of moisture content changes, thanks to its apparent simplicity and its high resolution characteristics. However, cross-hole radar requires closely spaced (a few meters), plastic-cased boreholes, that are rarely available as a standard feature in sites of practical interest. Unlike cross-hole applications, Vertical Radar Profiles (VRP) require only one borehole, with practical and financial benefits. High-resolution, time-lapse VRPs have been acquired at a crude oil contaminated site in Trecate, Northern Italy, on a few existing boreholes originally developed for remediation via bioventing. The dynamic water table conditions, with yearly oscillations of roughly 5 m from 6 to 11 m bgl, offers a good opportunity to observe via VRP a field scale drainage-imbibition process. Arrival time inversion has been carried out using a regularized tomographic algorithm, in order to overcome the noise introduced by first arrival picking. Interpretation of the vertical profiles in terms of moisture content has been based on standard models (Topp et al., 1980; Roth et al., 1990). The sedimentary sequence manifests itself as a cyclic pattern in moisture content over most of the profiles. We performed preliminary Richards' equation simulations with time varying later table boundary conditions, in order to estimate the unsaturated flow parameters, and the results have been compared with laboratory evidence from cores.

  4. Key to GHG fluxes from organic soils: site characteristics, agricultural practices or water table management?

    Science.gov (United States)

    Tiemeyer, Bärbel

    2015-04-01

    Drained peatlands are hotspots of greenhouse gas (GHG) emissions. Agriculture is the major land use type for peatlands in Germany and other European countries, but strongly varies in its intensity regarding the groundwater level and the agricultural management. Although the mean annual water table depth is sometimes proposed as an overall predictor for GHG emissions, there is a strong variability of its effects on different peatlands. Furthermore, re-wetting measures generally decrease carbon dioxide emissions, but may strongly increase methane emissions. We synthesized 250 annual GHG budgets for 120 different sites in 13 German peatlands. Carbon dioxide (net ecosystem exchange and ecosystem respiration), nitrous oxide and methane fluxes were measured with transparent and opaque manual chambers. Land management ranged from very intensive use with arable land or grassland with up to five cuts per year to partially or completely re-wetted peatlands. Besides the GHG fluxes, biomass yield, fertilisation, groundwater level, climatic data, vegetation composition and soil properties were measured. Overall, we found a large variability of the total GHG budget ranging from small uptakes to extremely high emissions (> 70 t CO2-equivalents/(ha yr)). At nearly all sites, carbon dioxide was the major component of the GHG budget. Site conditions, especially the nitrogen content of the unsaturated zone and the intra-annual water level distribution, controlled the GHG emissions of the agricultural sites. Although these factors are influenced by natural conditions (peat type, regional hydrology), they could be modified by an improved water management. Agricultural management such as the number of cuts had only a minor influence on the GHG budgets. At the level of individual peatlands, higher water levels always decreased carbon dioxide emissions. In nearly all cases, the trade-off between reduced carbon dioxide and increased methane emissions turned out in favour of the re

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Science.gov (United States)

    Migration_USER, IPDS; Wiley, Michael J.; Wilcox, Douglas A.

    2016-01-01

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

  7. Effects of experimental water table and temperature manipulations on ecosystem CO2 fluxes in an Alaskan rich fen

    Science.gov (United States)

    Chivers, M.R.; Turetsky, M.R.; Waddington, J.M.; Harden, J.W.; McGuire, A.D.

    2009-01-01

    Peatlands store 30% of the world's terrestrial soil carbon (C) and those located at northern latitudes are expected to experience rapid climate warming. We monitored growing season carbon dioxide (CO2) fluxes across a factorial design of in situ water table (control, drought, and flooded plots) and soil warming (control vs. warming via open top chambers) treatments for 2 years in a rich fen located just outside the Bonanza Creek Experimental Forest in interior Alaska. The drought (lowered water table position) treatment was a weak sink or small source of atmospheric CO2 compared to the moderate atmospheric CO2 sink at our control. This change in net ecosystem exchange was due to lower gross primary production and light-saturated photosynthesis rather than increased ecosystem respiration. The flooded (raised water table position) treatment was a greater CO2 sink in 2006 due largely to increased early season gross primary production and higher light-saturated photosynthesis. Although flooding did not have substantial effects on rates of ecosystem respiration, this water table treatment had lower maximum respiration rates and a higher temperature sensitivity of ecosystem respiration than the control plot. Surface soil warming increased both ecosystem respiration and gross primary production by approximately 16% compared to control (ambient temperature) plots, with no net effect on net ecosystem exchange. Results from this rich fen manipulation suggest that fast responses to drought will include reduced ecosystem C storage driven by plant stress, whereas inundation will increase ecosystem C storage by stimulating plant growth. ?? 2009 Springer Science+Business Media, LLC.

  8. Rotating Water Table for the Determination of Non-Steady Forces in a Turbine Stage Through Modified Hydraulic Analogy

    OpenAIRE

    J. S. Rao; E. Raghavacharyulu; Seshadri, V.; V.V.R. Rao

    1983-01-01

    Determination of non-steady forces in a real turbine stage is difficult due to the local flow conditions, for example high pressures, high temperatures and in-accessibility to the region etc. Experimentation in a real turbine is also prohibitive due to the costs involved. An alternate method of arriving at these non-steady forces through the use of modified hydraulic analogy is discussed. A rotating water table facility, developed and fabricated based on the principles of modified hydraulic a...

  9. Distinguishing Between the Partial-Mapping Preparation Hypothesis and the Failure-to-Engage Hypothesis of Residual Switch Costs

    NARCIS (Netherlands)

    Lindsen, Job P.; de Jong, Ritske

    2010-01-01

    Lien, Ruthruff, Remington, & Johnston (2005) reported residual switch cost differences between stimulus response (S-R) pairs and proposed the partial-mapping preparation (PMP) hypothesis, which states that advance preparation will typically be limited to a subset of S-R pairs because of structural c

  10. Distinguishing between the Partial-Mapping Preparation Hypothesis and the Failure-to-Engage Hypothesis of Residual Switch Costs

    Science.gov (United States)

    Lindsen, Job P.; de Jong, Ritske

    2010-01-01

    Lien, Ruthruff, Remington, & Johnston (2005) reported residual switch cost differences between stimulus-response (S-R) pairs and proposed the partial-mapping preparation (PMP) hypothesis, which states that advance preparation will typically be limited to a subset of S-R pairs because of structural capacity limitations, to account for these…

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

    Directory of Open Access Journals (Sweden)

    Krzysztof Micun

    2016-05-01

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

  12. "How low can it go?" - Scenarios for the future of water tables and groundwater irrigated agriculture in India

    Science.gov (United States)

    Modi, V.; Fishman, R.

    2010-12-01

    Groundwater irrigation, while critical for food production and rural livelihood in many developing countries, is often unsustainable. India, the world’s largest consumer of groundwater, mostly for irrigation, is a prime example: data suggests water tables are falling in the most of its productive regions. Because of the long-term consequences for the viability and efficiency of agriculture, it is important to know how far water tables might fall and what will eventually stabilize them: will it be a reduction in water use and increases in water use efficiency (a sustainable path) or more pessimistically, an energy ‘crunch’ or the hydrological ‘bottom’. Using national-level data, we document an alarming trend of non-decreasing water withdrawals supported by increasing energy use and little, if any, improvement in efficiency. We also study in detail a particular hot spot of advanced depletion that presents a grave warning signal of how far things can go if allowed to proceed on their present course. In our study area, water tables have been falling rapidly for three decades now and reach as much as 200m, with the astounding consequence that energy use for pumping, subsidized by the state, is now worth more than the income farmers generate from its use. Despite this, the large potential for water savings in agriculture there is still unexploited. We discuss policy measures that can prevent other parts of the country from following the same disastrous trajectory.

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

    Directory of Open Access Journals (Sweden)

    Christine Stumpp

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

  14. Multi-decadal water-table manipulation alters peatland hydraulic structure and moisture retention.

    Science.gov (United States)

    Moore, Paul; Morris, Paul; Waddington, James

    2015-04-01

    Peatlands are a globally important store of freshwater and soil carbon. However, there is a concern that these water and carbon stores may be at risk due to climate change as vapour pressure deficits, evapotranspiration and summer moisture deficits are expected to increase, leading to greater water table (WT) drawdown in northern continental regions where peatlands are prevalent. We argue that in order to evaluate the hydrological response (i.e. changes in WT level, storage, surface moisture availability, and moss evaporation) of peatlands under future climate change scenarios, the hydrophysical properties of peat and disparities between microforms must be well understood. A peatland complex disturbed by berm construction in the 1950's was used to examine the long-term impact of WT manipulation on peatland hydraulic properties and moisture retention at three adjacent sites with increasing average depth to WT (WET, INTermediate reference, and DRY). All three sites exhibited a strong depth dependence for hydraulic conductivity, specific yield, and bulk density. Moreover, the effect of microform on near-surface peat properties tended to be greater than the site effect. Bulk density was found to explain a high amount of variance (r2 > 0.69) in moisture retention across a range of pore water pressures (-15 to -500 cm H2O), where bulk density tended to be higher in hollows. The estimated residual water content for surface Sphagnum samples, while on average lower in hummocks (0.082 m3 m-3) versus hollows (0.087 m3 m-3), increased from WET (0.058 m3 m-3) to INT (0.088 m3 m-3) to DRY (0.108 m3 m-3) which has important implications for moisture stress under conditions of persistent WT drawdown. While we did not observe significant differences between sites, we did observe a greater proportional coverage and greater relative height of hummocks at the drier sites. Given the potential importance of microtopographic succession for altering peatland hydraulic structure, our

  15. Modeling relationships between water table depth and peat soil carbon loss in Southeast Asian plantations

    Science.gov (United States)

    Carlson, Kimberly M.; Goodman, Lael K.; May-Tobin, Calen C.

    2015-07-01

    Plantation-associated drainage of Southeast Asian peatlands has accelerated in recent years. Draining exposes the upper peat layer to oxygen, leading to elevated decomposition rates and net soil carbon losses. Empirical studies indicate positive relationships between long-term water table (WT) depth and soil carbon loss rate in peatlands. These correlations potentially enable using WT depth as a proxy for soil carbon losses from peatland plantations. Here, we compile data from published research assessing WT depth and carbon balance in tropical plantations on peat. We model net carbon loss from subsidence studies, as well as soil respiration (heterotrophic and total) from closed chamber studies, as a function of WT depth. WT depth across all 12 studies and 59 sites is 67 ± 20 cm (mean ± standard deviation). Mean WT depth is positively related to net carbon loss, as well as soil respiration rate. Our models explain 45% of net carbon loss variation and 45-63% of soil respiration variation. At a 70 cm WT depth, the subsidence model suggests net carbon loss of 20 tC ha-1 yr-1 (95% confidence interval (CI) 18-22 tC ha-1 yr-1) for plantations drained for >2 yr. Closed chamber-measured total soil respiration at this depth is 20 tC-CO2 ha-1 yr-1 (CI 17-24 tC-CO2 ha-1 yr-1) while heterotrophic respiration is 17 tC-CO2 ha-1 yr-1 (CI 14-20 tC-CO2 ha-1 yr-1), ˜82% of total respiration. While land use is not a significant predictor of soil respiration, WT depths are greater at acacia (75 ± 16 cm) than oil palm (59 ± 15 cm) sample sites. Improved spatio-temporal sampling of the full suite of peat soil carbon fluxes—including fluvial carbon export and organic fertilizer inputs—will clarify multiple mechanisms leading to carbon loss and gain, supporting refined assessments of the global warming potential of peatland drainage.

  16. Hillslope and stream connections to water tables in montane meadows of the southern Sierra Nevada, California

    Science.gov (United States)

    Conklin, M. H.; Lucas, R. G.

    2011-12-01

    Montane meadows are often areas of groundwater discharge. In this study we characterized the groundwater - surface water interactions of two meadow systems and their connectivity to the surrounding catchment . We analyzed groundwater elevation data in 24 wells in two meadows located in the southern Sierra Nevada. Well transects extended from the meadow centers near the stream, to the meadow edged, and into the adjacent forest-where wells were drilled into the weathered granite saprock layer. Water samples were collected from the monitoring wells and from streams associated with the meadow systems and analyzed for major ions and stable water isotopes. Ground water elevations in the monitoring wells were used to calculate daily evapotranspiration (ET) values. These values show that locations on the meadow slopes and near the meadow edges are losing water to the atmosphere at near potential evapotranspiration rates during the height of the growing season. ET signals from wells near the meadow streams are muted, likely due to the vegetation utilizing the available surface water at these locations. Wells installed in the saprock layer, outside of the meadow boundaries, show diurnal fluctuations in sync with fluctuations observed at the meadow edge. This trend persists after the meadow vegetation senesces, indicating that groundwater elevations in the meadow, especially near the meadow edge, are significantly influenced by the adjacent hillslope saprock layer and forest ET. Geochemical sampling results indicate that the meadow streams are predominantly fed by snowmelt in the spring and early summer, moving toward more influence from base flow in the late summer and early fall. Results from the geochemical analysis established the connections of the hillslope to the meadow water tables and of the meadow subsurface waters to the down-gradient streams. Our results indicate that the these meadows are directly connected to the shallow sub-surface processes in the up gradient

  17. The impact of changes in the water table and soil moisture on structural stability of buildings and foundation systems : systematic review CEE10-005 (SR90).

    OpenAIRE

    2012-01-01

    This Systematic Review aims to consider the impact of changes in the ground water table and soil moisture regime on structural stability of buildings and foundation systems. The possible changes in the water table levels and soil moisture conditions are expected as a result of environmental change. Building and infrastructure damage occurs where differential movements exceed the thresholds that the buildings or infrastructure can sustain. At locations where uniform vertical settlement domi...

  18. Responses of CO2 emission and pore water DOC concentration to soil warming and water table drawdown in Zoige Peatlands

    Science.gov (United States)

    Yang, Gang; Wang, Mei; Chen, Huai; Liu, Liangfeng; Wu, Ning; Zhu, Dan; Tian, Jianqing; Peng, Changhui; Zhu, Qiuan; He, Yixin

    2017-03-01

    Peatlands in Zoige Plateau contains more than half of peatland carbon stock in China. This part of carbon is losing with climate change through dissolved organic carbon (DOC) export and carbon dioxide (CO2) emissions, both of which are vulnerable to the environmental changes, especially on the Zoige Plateau with a pace of twice the observed rate of global climate warming. This research aimed to understand how climate change including soil warming, rainfall reduction and water table change affect CO2 emissions and whether the trends of changes in CO2 emission are consistent with those of pore water DOC concentration. A mesocosm experiment was designed to investigate the CO2 emission and pore water DOC during the growing seasons of 2009-2010 under scenarios of passive soil warming, 20% rainfall reduction and changes to the water table levels. The results showed a positive relationship between CO2 emission and DOC concentration. For single factor effect, we found no significant relationship between water table and CO2 emission or DOC concentration. However, temperature at 5 cm depth was found to have positive linear relationship with CO2 emission and DOC concentration. The combined effect of soil warming and rainfall reduction increased CO2 emission by 96.8%. It suggested that the drying and warming could stimulate potential emission of CO2. Extending this result to the entire peatland area in Zoige Plateau translates into 0.45 Tg CO2 emission per year over a growing season. These results suggested that the dryer and warmer Zoige Plateau will increase CO2 emission. We also found the contribution rate of DOC concentration to CO2 emission was increased by 12.1% in the surface layer and decreased by 13.8% in the subsurface layer with combined treatment of soil warming and rainfall reduction, which indicated that the warmer and dryer environmental conditions stimulate surface peat decomposition process.

  19. Annual safe groundwater yield in a semiarid basin using combination of water balance equation and water table fluctuation

    Science.gov (United States)

    Rezaei, Abolfazl; Mohammadi, Zargham

    2017-10-01

    The safe groundwater yield plays a major role in the appropriate management of groundwater systems, particularly in (semi-)arid areas like Iran. This study incorporates both the water balance equation and the water table fluctuation to estimate the annual safe yield of the unconfined aquifer in the eastern part of the Kaftar Lake, an Iranian semiarid region. Firstly, the water balance year 2002-03, owing same water table elevation at the beginning and year-end, was chosen from the monthly representative groundwater hydrograph of the aquifer to be taken into account as a basic water year for determining the safe yield. Then the ratio of the total groundwater pumping to the annual groundwater recharge in the selected water balance year together with the quantity of total recharge occurred in the wet period (October to May) of the year of interest were applied to evaluate the annual safe yield at the initiation of the dry period (June to September) of the year of interest. Knowing the annual safe groundwater withdrawal rate at the initiation of each dry period could be helpful to decision makers in managing groundwater resources conservation. Analysis results indicate that to develop a safe management strategy in the aquifer; the ratio of the annual groundwater withdrawal to the annually recharged volume should not exceed 0.69. In the water year 2003-04 where the ratio is equal to 0.52, the water table raised up (about 0.48 m) while the groundwater level significantly declined (about 1.54 m) over the water year 2007-08 where the ratio of the annual groundwater withdrawal to the annually recharged volume (i.e., 2.76) is larger than 0.69.

  20. Subsidence and soil CO2 efflux in tropical peatland in southern Thailand under various water table and management conditions

    Directory of Open Access Journals (Sweden)

    T. Nagano

    2013-12-01

    Full Text Available At the Bacho peatland in southern Thailand, peat subsidence was measured at four locations on abandoned agricultural land (degraded peat swamp forest and at one location in a conservation zone, at monthly intervals over a period of more than 20 years. Average peat subsidence rates during the observation period were 3.1–5.2 cm y−1 on the degraded peatland, reducing to 1.8–2.6 cm y−1 when peat loss due to field fires was discounted, and 1.0 cm y−1 reducing to 0.7 cm y-1 in the conservation zone. Due to martial law restrictions on access to the Bacho site, measurements of the peat soil respiration rate under various water table conditions were made mostly at other sites in Thailand with similar climate. During these measurements the position of the water table ranged from 0.92 m above the peat surface to more than one metre below it, and daily mean respiration rates ranged from 0.57 to 8.20 μmol CO2 m−2 s−1. The CO2 efflux attributed to peat respiration was 13.7–18.9 Mg ha−1 y−1 on the degraded peatland but only 7.5 Mg ha−1 y−1 in the conservation zone. To simulate the CO2 efflux resulting from soil respiration at Bacho on the basis of data collected elsewhere, we developed an empirical three-stage model (NAIS Peat Model that treats the position of the water table as a proxy variable. The observed values of peat subsidence were in good agreement with simulated values of CO2 efflux in two tests. The implications for peatland management are considered.

  1. Experimental response of Salix cuttings to sudden water table changing dynamics

    Science.gov (United States)

    Gorla, L.; Signarbieux, C.; Turberg, P.; Buttler, A.; Perona, P.

    2013-12-01

    Hydropower production, agriculture and other human activities change the natural flow regime of rivers, in turn impacting the riparian environment. Inadequate flow rules (e.g., minimal or residual flows) reflecting our limited understanding of eco-hydrological processes have thus been applied since decades. The main challenge for an eco-sustainable water management is to quantify the effects of flow regulation on channel morphodynamics and biological processes. We present a controlled laboratory experiment to investigate riparian vegetation (Salix Viminalis) response to forced water table changing dynamics, from one water regime to another, in a temperate region (Switzerland). Three synthetic flow regimes have been simulated and applied to three batteries of Salix cuttings (60 in total) growing outdoor within plastic pots, each about 1 meter tall. After an initial period where all pots undergone the same oscillations in order to uniform the plants initial conditions, the experiment started, and the water dynamic was changed for two out of three batteries. In particular, one treatment simulated a minimal flow policy, which drastically impacts the low and the medium-low components of the hydrograph, but not the extremes. The other treatment reproduced only the low frequencies corresponding to the seasonal trend of the natural flow regime, still applied on the third battery. Cuttings transitory response dynamics has been quantified by continuous sap flow and water potential measurements, and by regularly collecting growth parameters, as well as leaves photosynthesis, fluorescence, and pictures of each plant. At the end of the experiment, all cuttings were carefully removed and the both above and below ground biomass analyzed in detail. Particularly, the 3D root structure was obtained by High Resolution Computer Tomography. Our analyses reveal a clear dependence between roots distribution and water regime reflecting the need for adaptation, which are also in agreement

  2. Effect of water-table fluctuations on the degradation of Sphagnum phenols in surficial peats

    Science.gov (United States)

    Abbott, Geoffrey D.; Swain, Eleanor Y.; Muhammad, Aminu B.; Allton, Kathryn; Belyea, Lisa R.; Laing, Christopher G.; Cowie, Greg L.

    2013-04-01

    A much improved understanding of how water-table fluctuations near the surface affect decomposition and preservation of peat-forming plant litter and surficial peats is needed in order to predict possible feedbacks between the peatland carbon cycle and the global climate system. In this study peatland plants (bryophytes and vascular plants), their litter and peat cores were collected from the Ryggmossen peatland in the boreonemoral zone of central Sweden. The extracted insoluble residues from whole plant tissues were depolymerized using thermally assisted hydrolysis and methylation (THM) in the presence of both unlabelled and 13C-labelled tetramethylammonium hydroxide (TMAH) which yielded both vascular plant- and Sphagnum-derived phenols. Methylated 4-isopropenylphenol (IUPAC: 1-methoxy-4-(prop-1-en-2-yl)benzene), methylated cis- and trans-3-(4'-hydroxyphen-1-yl)but-2-enoic acid (IUPAC: (E/Z)-methyl 3-(4-methoxyphenyl)but-2-enoate), and methylated 3-(4'-hydroxyphen-1-yl)but-3-enoic acid (IUPAC: methyl 3-(4-methoxyphenyl)but-3-enoate) (van der Heijden et al., 1997) are confirmed as TMAH thermochemolysis products of "bound" sphagnum acid and also as being specific to Sphagnum mosses. These putative biomarkers were also significant components in the unlabelled TMAH thermochemolysis products from the depolymerization of ultrasonically extracted samples from eight peat cores, one from a hummock and one from a hollow at each of the four stages along the bog plateau-to-swamp forest gradient. We have proposed and measured two parameters namely (i) σ which is defined as the total amount of these four molecules normalised to 100 mg of OC; and (ii) an index (SR%) which is the ratio of σ to the Λ parameter giving a measure of the relative amounts of "bound" sphagnum acid to the "bound" vascular plant phenols in peat moss and the surficial peat layers. Changes in σ and SR% down the bog plateau (BP), bog margin (BM) and fen lagg (FL) cores in the Ryggmossen mire indicates

  3. TOPMODEL simulations of streamflow and depth to water table in Fishing Brook Watershed, New York, 2007-09

    Science.gov (United States)

    Nystrom, Elizabeth A.; Burns, Douglas A.

    2011-01-01

    TOPMODEL, a physically based, variable-source area rainfall-runoff model, was used to simulate streamflow and depth to water table for the period January 2007-September 2009 in the 65.6 square kilometers of Fishing Brook Watershed in northern New York. The Fishing Brook Watershed is located in the headwaters of the Hudson River and is predominantly forested with a humid, cool continental climate. The motivation for applying this model at Fishing Brook was to provide a simulation that would be effective later at this site in modeling the interaction of hydrologic processes with mercury dynamics.

  4. Testing of NAPL simulator to predict migration of a light nonaqueous phase liquid (LNAPL) under water table fluctuation in a sandy medium

    Institute of Scientific and Technical Information of China (English)

    周劲风; 李雁; 徐军

    2014-01-01

    Nanoqueous phase liquid (NAPL) simulator is a powerful and popular mathematical model for modeling the flow and transport of non-aqueous phase liquids in subsurface, but the testing of its feasibility under water table fluctuation has received insufficient attention. The feature in a column test was tested through two cycles of water table fluctuation. The sandy medium in the column was initially saturated, and each cycle of water table fluctuation consisted of one water table falling and one rising, resulting in a drainage and an imbibition of the medium, respectively. It was found that the difference between the simulated and measured results in the first drainage of the column test was minor. However, with the propagation of the water table fluctuations, the simulation errors increased, and the simulation accuracy was not acceptable except for the first drainage in the two fluctuation cycles. The main reason was proved to be the estimation method of residual saturation used in this simulator. Also, based on the column tests, it was assumed that the resulting residual saturation from an incomplete imbibition process was a constant, with a value equal to that of the residual value resulting from the main imbibition process. The results obtained after modifying NAPL simulator with this assumption were found to be more accurate in the first cycle of water table fluctuation, but this accuracy decreased rapidly in the second one. It is concluded that NAPL simulator is not adequate in the case of LNAPL migration under water table fluctuation in sandy medium, unless a feasible assumption to estimate residual saturation is put forward.

  5. Spatially variable water table recharge and the hillslope hydrologic response: Analytical solutions to the linearized hillslope Boussinesq equation

    Science.gov (United States)

    Dralle, David N.; Boisramé, Gabrielle F. S.; Thompson, Sally E.

    2014-11-01

    The linearized hillslope Boussinesq equation, introduced by Brutsaert (1994), describes the dynamics of saturated, subsurface flow from hillslopes with shallow, unconfined aquifers. In this paper, we use a new analytical technique to solve the linearized hillslope Boussinesq equation to predict water table dynamics and hillslope discharge to channels. The new solutions extend previous analytical treatments of the linearized hillslope Boussinesq equation to account for the impact of spatiotemporal heterogeneity in water table recharge. The results indicate that the spatial character of recharge may significantly alter both steady state subsurface storage characteristics and the transient hillslope hydrologic response, depending strongly on similarity measures of controls on the subsurface flow dynamics. Additionally, we derive new analytical solutions for the linearized hillslope-storage Boussinesq equation and explore the interaction effects of recharge structure and hillslope morphology on water storage and base flow recession characteristics. A theoretical recession analysis, for example, demonstrates that decreasing the relative amount of downslope recharge has a similar effect as increasing hillslope convergence. In general, the theory suggests that recharge heterogeneity can serve to diminish or enhance the hydrologic impacts of hillslope morphology.

  6. Flood regime and water table determines tree distribution in a forest-savanna gradient in the Brazilian Pantanal.

    Science.gov (United States)

    Ferreira-Júnior, Walnir G; Schaefer, Carlos E G R; Cunha, Cátia N; Duarte, Temilze G; Chieregatto, Luiz C; Carmo, Flávia M S

    2016-01-01

    This study aimed to recognized the preferential location of species of the tree sinusiae in response to a moisture gradient in Pantanal Matogrossense, Brazil. We established sampling plots of arboreal sinusiae along a soil moisture and flood gradient. Piezometers were installed, allowing monthly measurements of water table depth and flood height during one year. Detrended Correspondence Analysis, Gradient Direct Analysis, Multi-response Permutation Procedures and Indicator Species Analysis were performed to evaluate the effect of moisture gradient on tree distribution. The annual variation of water table is shallower and similar in Seasonally Flooded Forest and Termite Savanna, with increasing depths in Open Savanna, Savanna Forest and Dry Forest. Circa 64% of the species were characterized as having a preferential location in "terrestrial habitats normally not subjected to inundation", while 8% preferentially occur in "wet habitats". Lowest tree richness in flood-affected vegetation types is related to both present-day high climatic seasonality and Late Pleistocene dry paleoclimates in the Pantanal wetland. The tree distribution across different formations in the Pantanal shows a direct relationship with soil moisture gradient.

  7. Estimating groundwater evapotranspiration by a subtropical pine plantation using diurnal water table fluctuations: Implications from night-time water use

    Science.gov (United States)

    Fan, Junliang; Ostergaard, Kasper T.; Guyot, Adrien; Fujiwara, Stephen; Lockington, David A.

    2016-11-01

    Exotic pine plantations have replaced large areas of the native forests for timber production in the subtropical coastal Australia. To evaluate potential impacts of changes in vegetation on local groundwater discharge, we estimated groundwater evapotranspiration (ETg) by the pine plantation using diurnal water table fluctuations for the dry season of 2012 from August 1st to December 31st. The modified White method was used to estimate the ETg, considering the night-time water use by pine trees (Tn). Depth-dependent specific yields were also determined both experimentally and numerically for estimation of ETg. Night-time water use by pine trees was comprehensively investigated using a combination of groundwater level, sap flow, tree growth, specific yield, soil matric potential and climatic variables measurements. Results reveal a constant average transpiration flux of 0.02 mm h-1 at the plot scale from 23:00 to 05:00 during the study period, which verified the presence of night-time water use. The total ETg for the period investigated was 259.0 mm with an accumulated Tn of 64.5 mm, resulting in an error of 25% on accumulated evapotranspiration from the groundwater if night-time water use was neglected. The results indicate that the development of commercial pine plantations may result in groundwater losses in these areas. It is also recommended that any future application of diurnal water table fluctuation based methods investigate the validity of the zero night-time water use assumption prior to use.

  8. Effects of a raised water table on greenhouse gas emissions and celery yield from agricultural peat under climate warming conditions

    Science.gov (United States)

    Matysek, Magdalena; Zona, Donatella; Leake, Jonathan; Banwart, Steven

    2017-04-01

    Peatlands are globally important areas for carbon preservation: covering only 3% of world's land, they store 30% of total soil carbon. At the same time, peat soils are widely utilised in agriculture: in Europe 14% of peatland area is under cultivation, 40% of UK peatlands have been drained for agricultural use and 24% of deep peat area in England is being farmed. One of the most important regions for crop production on lowland peats in the UK are the East Anglian Fenlands (the Fens): an area of drained peatlands in East England. 88% of the Fenland area is cultivated, sustaining around 4000 farms and supplying 37% of total vegetable production in England. The soils of the area are fertile (89% of agricultural land being classified as grade 1 or 2) and so crops with high nutritional demands tend to dominate. It is estimated that Fenland peats store 41 Tg of Carbon, which is lost from the ecosystem at a rate of 0.4 Tg C/yr. The Fens are at risk due to continued drainage-induced volume loss of the peat layer via shrinkage, compaction and oxidation, which are estimated to result in wastage rate of 2.1 cm/yr. Cultivation of peat soil requires drainage as most crops are intolerant of root-zone anoxia: this leads to creation of oxic conditions in which organic matter becomes vulnerable to mineralisation by aerobic microorganisms. It is, therefore, crucial to find a water table level which would minimise peat loss and at the same time allow for economically viable crop growth. Despite the importance of preservation of agricultural peats, there is a lack of studies which attempt to find water table level that strikes a balance between crop yield and greenhouse gas production. The future of the Fens is overshadowed by another uncertainty: increases in temperature brought by the climate change. It is estimated that average global temperature increase expected by the end of this century (relative to 1986-2005) would be within the range of 0.3-4.8°C, depending on the scenario

  9. Water table response to an experimental alley farming trial: dissecting the spatial and temporal structure of the data.

    Science.gov (United States)

    Noorduijn, S L; Ghadouani, A; Vogwill, R; Smettem, K R J; Legendre, P

    2010-09-01

    Clearing vegetation for traditional agriculture diminishes native habitat and reduces plant transpiration, leading to increased groundwater recharge and onset of dryland salinization due to rising groundwater and mobilization of salt stores in the soil profile. This change in hydrology and salinity can also negatively affect biodiversity in many semiarid regions. Alternating native perennial tree belts with mono-species agriculture within the tree belt alleys is one possible system that can provide recharge control and recover some of the ecosystem services of degraded agricultural landscapes. To assess the effect of this agroforestry technique on groundwater levels, an alley farming trial was established in 1995, incorporating different combinations of belt width, alley width, and revegetation density. Transects of piezometers within each design have been monitored from October 1995 to January 2008. The data set consisted of 70 piezometers monitored on 39 dates. Two trends were observed within the raw data: An increase in water table depth with time and an increase in the range of depths monitored at the site were clearly discernible. However, simple hydrograph analysis of the data has proved unsuccessful at distinguishing the effect of the tree belts on the water table morphology. The statistical techniques employed in this paper to show the effect of the experiment on the water table were variation partitioning, principal coordinates of neighbor matrices (PCNM), and canonical redundancy analysis (RDA). The environmental variables (alley farming design, distance of piezometer from the tree belt, and percentage vegetation cover including edge effect) explained 20-30% of the variation of the transformed and detrended data for the entire site. The spatial PCNM variables explained a further 20-30% of the variation. Partitioning of the site into a northern and southern block increased the proportion of explained variation for the plots in the northern block. The

  10. Relative impacts of key drivers on the response of the water table to a major alley farming experiment

    Directory of Open Access Journals (Sweden)

    A. Ghadouani

    2009-11-01

    Full Text Available Widespread clearing of native vegetation in Southwest Western Australia has led to land degradation associated with rising groundwater, secondary salinisation and waterlogging. Re-establishing deep-rooted perennial vegetation across parts of the landscape is one technique for managing land degradation. Alley farming is an agroforestry practice where multiple perennial tree belts are planted in alternation with traditional agricultural crops. To identify the best configuration (belt width versus alley width for controlling rising groundwater levels and providing viable economic returns, a large scale experiment was established in 1995. The experiment contains seven different alley farming designs, each with transects of piezometers running across tree belts into adjacent alleys to monitor changes in the groundwater level. Two control piezometers were also installed in an adjacent paddock. Groundwater at the site is shallow (<3 m and of poor quality (pH 3–5, Ec 2.1–45.9 mS cm−1 so root water uptake from the saturated zone is limited.

    Simple hydrograph analysis could not separate treatment effects on the water table response. Subsequent statistical analysis revealed that 20–30% of the variability in the water table data over the 12 year study period was attributable to the alley farming experiment. To futher investigate the effect of the experiment on groundwater response, additional hydrograph analysis was conducted to compare the trends in the control piezometers in relation to those located within the belts. A difference of 0.9 m was observed between the mean groundwater levels in the control piezometers and the mean levels in the perennial belt piezometers. For a mean specific yield of 0.03 m3 m−3 (standard deviation of 0.03 m3 m−3 this equates to an additional average annual water use of 27 mm yr−1 (standard deviation of 33 mm yr−1 by the

  11. Effect of taxonomic resolution on ecological and palaeoecological inference - a test using testate amoeba water table depth transfer functions

    Science.gov (United States)

    Mitchell, Edward A. D.; Lamentowicz, Mariusz; Payne, Richard J.; Mazei, Yuri

    2014-05-01

    Sound taxonomy is a major requirement for quantitative environmental reconstruction using biological data. Transfer function performance should theoretically be expected to decrease with reduced taxonomic resolution. However for many groups of organisms taxonomy is imperfect and species level identification not always possible. We conducted numerical experiments on five testate amoeba water table (DWT) transfer function data sets. We sequentially reduced the number of taxonomic groups by successively merging morphologically similar species and removing inconspicuous species. We then assessed how these changes affected model performance and palaeoenvironmental reconstruction using two fossil data sets. Model performance decreased with decreasing taxonomic resolution, but this had only limited effects on patterns of inferred DWT, at least to detect major dry/wet shifts. Higher-resolution taxonomy may however still be useful to detect more subtle changes, or for reconstructed shifts to be significant.

  12. Relative impacts of key drivers on the response of the water table to a major alley farming experiment

    Science.gov (United States)

    Noorduijn, S. L.; Smettem, K. R. J.; Vogwill, R.; Ghadouani, A.

    2009-11-01

    Widespread clearing of native vegetation in Southwest Western Australia has led to land degradation associated with rising groundwater, secondary salinisation and waterlogging. Re-establishing deep-rooted perennial vegetation across parts of the landscape is one technique for managing land degradation. Alley farming is an agroforestry practice where multiple perennial tree belts are planted in alternation with traditional agricultural crops. To identify the best configuration (belt width versus alley width) for controlling rising groundwater levels and providing viable economic returns, a large scale experiment was established in 1995. The experiment contains seven different alley farming designs, each with transects of piezometers running across tree belts into adjacent alleys to monitor changes in the groundwater level. Two control piezometers were also installed in an adjacent paddock. Groundwater at the site is shallow (agroforestry system. It is concluded that declining annual rainfall is the principal control on hydrograph response at the site, whilst perennial biomass development has a lesser impact on water table depth.

  13. Soil CO2 efflux in a degraded raised bog is regulated by water table depth rather than recent plant assimilate

    Directory of Open Access Journals (Sweden)

    U.H. Kritzler

    2016-02-01

    Full Text Available Understanding the climatic and biological factors that regulate soil carbon dioxide (CO2 efflux is crucial in peatlands because they contain a large proportion of terrestrial carbon (C. We predicted that rainfall reduction would increase soil CO2 efflux, and that cessation of below-ground allocation of recent plant assimilate would reduce soil CO2 efflux. These predictions were tested in the field using rainfall shelters that allowed a maximum of 40 % of rainfall onto 2 × 2 m plots by diverting rainwater from the shelter roofs with guttering, and by girdling stems of the dominant plant, Calluna vulgaris, for two years. We also used 13CO2-pulse labelling of intact monoliths at ambient CO2 concentrations to trace recent assimilate from plant shoots to roots, bulk soil, leachate, dissolved organic carbon (DOC and soil CO2 efflux . Soil CO2 efflux in the sheltered plots increased in Year 1 but not in Year 2, and we found a positive relationship between soil CO2 efflux and water table depth. Our data indicate that lowering the water table below a critical threshold (15–20 cm affects soil CO2 efflux. Girdling of C. vulgaris shoots resulted in no measurable reduction in soil CO2 efflux, while only ~3 % of 13C fixed by shoots was recovered in soil CO2 efflux and DOC in the 20 days after labelling. Our findings show that below-ground allocation of recent assimilate from C. vulgaris plants > 6 years old has little impact on soil CO2 efflux.

  14. RELATIONSHIP AMONG EVAPORATION FLUX OF GROUNDWATER, DEPTH OF WATER TABLE AND NEGATIVE PRESSURE HEAD IN BARE SOIL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Evaporation of ground water is a part of moisture circulation in the field.And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water.According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure.By theoretical analysis of the experimental results, the main conclusions are drawn as follows.There are two abrupt points in every Q-H curve.The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section.When the depth of ground water table H is small, the evaporation flux of ground water is large.While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small.The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought.These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources.In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

  15. Modelling the effects of porous media deformation on the propagation of water-table waves in a sandy unconfined aquifer

    Science.gov (United States)

    Jazayeri Shoushtari, Seyed Mohammad Hossein; Cartwright, Nick

    2016-11-01

    This paper examines the influence of porous media deformation on water-table wave dispersion in an unconfined aquifer using a numerical model which couples Richards' equation to the poro-elastic model. The study was motivated by the findings of Shoushtari et al. (J Hydrol 533:412-440, 2016) who were unable to reproduce the observed wave dispersion in their sand flume data with either numerical Richards' equation models (assuming rigid porous media) or existing analytic solutions. The water-table wave dispersion is quantified via the complex wave number extracted from the predicted amplitude and phase profiles. A sensitivity analysis was performed to establish the influence of the main parameters in the poro-elastic model, namely Young's modulus (E) and Poisson's ratio (ν). For a short oscillation period (T = 16.4 s), the phase lag increase rate (k i) is sensitive to the chosen values of E and ν, demonstrating an inverse relationship with both parameters. Changes in the amplitude decay rate (k r), however, were negligible. For a longer oscillation period (T = 908.6 s), variations in the values of E and ν resulted in only small changes in both k r and k i. In both the short and long period cases, the poro-elastic model is unable to reproduce the observed wave dispersion in the existing laboratory data. Hence porous media deformation cannot explain the additional energy dissipation in the laboratory data. Shoushtari SMH, Cartwright N, Perrochet P, Nielsen P (2016) The effects of oscillation period on groundwater wave dispersion in a sandy unconfined aquifer: sand flume experiments and modelling. J Hydrol 533:412-440.

  16. Modelling the effects of porous media deformation on the propagation of water-table waves in a sandy unconfined aquifer

    Science.gov (United States)

    Jazayeri Shoushtari, Seyed Mohammad Hossein; Cartwright, Nick

    2017-03-01

    This paper examines the influence of porous media deformation on water-table wave dispersion in an unconfined aquifer using a numerical model which couples Richards' equation to the poro-elastic model. The study was motivated by the findings of Shoushtari et al. (J Hydrol 533:412-440, 2016) who were unable to reproduce the observed wave dispersion in their sand flume data with either numerical Richards' equation models (assuming rigid porous media) or existing analytic solutions. The water-table wave dispersion is quantified via the complex wave number extracted from the predicted amplitude and phase profiles. A sensitivity analysis was performed to establish the influence of the main parameters in the poro-elastic model, namely Young's modulus ( E) and Poisson's ratio ( ν). For a short oscillation period ( T = 16.4 s), the phase lag increase rate ( k i) is sensitive to the chosen values of E and ν, demonstrating an inverse relationship with both parameters. Changes in the amplitude decay rate ( k r), however, were negligible. For a longer oscillation period ( T = 908.6 s), variations in the values of E and ν resulted in only small changes in both k r and k i. In both the short and long period cases, the poro-elastic model is unable to reproduce the observed wave dispersion in the existing laboratory data. Hence porous media deformation cannot explain the additional energy dissipation in the laboratory data. Shoushtari SMH, Cartwright N, Perrochet P, Nielsen P (2016) The effects of oscillation period on groundwater wave dispersion in a sandy unconfined aquifer: sand flume experiments and modelling. J Hydrol 533:412-440.

  17. Real-time 4D ERT monitoring of river water intrusion into a former nuclear disposal site using a transient warping-mesh water table boundary (Invited)

    Science.gov (United States)

    Johnson, T.; Hammond, G. E.; Versteeg, R. J.; Zachara, J. M.

    2013-12-01

    The Hanford 300 Area, located adjacent to the Columbia River in south-central Washington, USA, is the site of former research and uranium fuel rod fabrication facilities. Waste disposal practices at site included discharging between 33 and 59 metric tons of uranium over a 40 year period into shallow infiltration galleries, resulting in persistent uranium contamination within the vadose and saturated zones. Uranium transport from the vadose zone to the saturated zone is intimately linked with water table fluctuations and river water intrusion driven by upstream dam operations. As river stage increases, the water table rises into the vadose zone and mobilizes contaminated pore water. At the same time, river water moves inland into the aquifer, and river water chemistry facilitates further mobilization by enabling uranium desorption from contaminated sediments. As river stage decreases, flow moves toward the river, ultimately discharging contaminated water at the river bed. River water specific conductance at the 300 Area varies around 0.018 S/m whereas groundwater specific conductance varies around 0.043 S/m. This contrast provides the opportunity to monitor groundwater/river water interaction by imaging changes in bulk conductivity within the saturated zone using time-lapse electrical resistivity tomography. Previous efforts have demonstrated this capability, but have also shown that disconnecting regularization constraints at the water table is critical for obtaining meaningful time-lapse images. Because the water table moves with time, the regularization constraints must also be transient to accommodate the water table boundary. This was previously accomplished with 2D time-lapse ERT imaging by using a finely discretized computational mesh within the water table interval, enabling a relatively smooth water table to be defined without modifying the mesh. However, in 3D this approach requires a computational mesh with an untenable number of elements. In order to

  18. Cartographic sign as a core of multimedia map prepared by non-cartographers in free map services

    Directory of Open Access Journals (Sweden)

    Medyńska-Gulij Beata

    2014-06-01

    Full Text Available Fundamentalne znaczenie znaków kartograficznych na tradycyjnej mapie nie budzi wątpliwości, jednak w przypadku multimedialnej mapy ich kluczowa funkcja nie jest już tak oczywista. W tych badaniach podjęto problem znaczenia znaku kartograficznego jako spoiwa mapy multimedialnej opracowanej przez nie-kartografa w darmowych serwisach mapowych. Zadaniem dla projektujących mapy stało się opracowanie mapy multimedialnej według ustalonych wstępnie zasad, w której kluczową rolę odgrywały znaki kartograficzne oraz przyzwyczajenia użytkowników Internetu. Porównanie wypełnionych arkuszy zadań przez uczestników badań skłania do wyciągnięcia generalnego wniosku, że znak kartograficzny powinien determinować projektowanie multimedialnej mapy w serwisach mapowych on-line. Pomimo opracowania pięciu różnych tematów map, można wymienić ogólne charakterystyki map, w których znak kartograficzny jest spoiwem.

  19. A guide to commonly used map projections prepared for use in HyperCard, 1988

    Science.gov (United States)

    Alpha, Tau Rho; Vigil, Joe F.; Buchholz, Lauren

    1988-01-01

    This guide briefly describes and illustrates the characteristics of 17 map projections commonly used to present thematic data. By means of simple sketches of the basic grid system of longitude and latitude known as the Earth's graticule, the guide shows examples of the following categories of map projections: planes (azimuthal), cones, cylinders, and miscellaneous. The text gives examples of thematic maps published by the U.S. Geological Survey that use various projections. The guide was created as a HyperCard "stack" for use only on the Macintosh family of computers. The guide consists of descriptive material only and does not contain a program for creating map projections.

  20. Preparation of earthquake-triggered landslide inventory maps using remote sensing and GIS technologies:Principles and case studies

    Institute of Scientific and Technical Information of China (English)

    Chong Xu

    2015-01-01

    Inventory maps of earthquake-triggered landslides can be constructed using several methods, which are often subject to obvious differences due to lack of commonly accepted criteria or principles. To solve this problem, the author describes the principles for preparing inventory maps of earthquake-triggered landslides, focusing on varied methods and their criteria. The principles include the following key points: all landslides should be mapped as long as they can be recognized from images; both the boundary and source area position of landslides should be mapped; spatial distribution pattern of earthquake-triggered landslides should be continuous; complex landslides should be divided into distinct groups;three types of errors such as precision of the location and boundary of landslides, false positive errors, and false negative errors of earthquake-triggered landslide inventories should be controlled and reduced; and inventories of co-seismic landslides should be constructed by the visual interpretation method rather than automatic extraction of satellite images or/and aerial photographs. In addition, selection of remote sensing images and creation of landslides attribute database are also dis-cussed in this paper. Then the author applies these principles to produce inventory maps of four events:the 12 May 2008 Wenchuan, China Mw 7.9, 14 April 2010 Yushu, China Mw 6.9, 12 January 2010 Haiti Mw 7.0, and 2007 Aysén Fjord, Chile Mw 6.2. The results show obvious differences in comparison with pre-vious studies by other researchers, which again attest to the necessity of establishment of unified principles for preparation of inventory maps of earthquake-triggered landslides.

  1. A Different Approach to Preparing Novakian Concept Maps: The Indexing Method

    Science.gov (United States)

    Turan Oluk, Nurcan; Ekmekci, Güler

    2016-01-01

    People who claim that applying Novakian concept maps in Turkish is problematic base their arguments largely upon the structural differences between the English and Turkish languages. This study aims to introduce the indexing method to eliminate problems encountered in Turkish applications of Novakian maps and to share the preliminary results of…

  2. T2 mapping with magnetization-prepared 3D TSE based on a modified BIR-4 T2 preparation.

    Science.gov (United States)

    Weidlich, Dominik; Schlaeger, Sarah; Kooijman, Hendrik; Börnert, Peter; Kirschke, Jan S; Rummeny, Ernst J; Haase, Axel; Karampinos, Dimitrios C

    2017-08-04

    The purpose of this work was to investigate the performance of the modified BIR-4 T2 preparation for T2 mapping and propose a method to remove T2 quantification errors in the presence of large B1 and B0 offsets. The theoretical investigation of the magnetization evolution during the T2 preparation in the presence of B1 and B0 offsets showed deviations from a mono-exponential T2 decay (two parameter fit). A three parameter fit was used to improve T2 accuracy. Furthermore, a two parameter fit with an additional saturation preparation scan was proposed to improve T2 accuracy and precision. These three fitting methods were compared based on simulations, phantom measurements and an in vivo healthy volunteer study of the neck musculature using a 3D TSE readout. The results based upon the pure two parameter fit overestimated T2 in regions with high B0 offsets (up to 40% in phantoms). The three parameter fit T2 values were robust to B0 offsets but with higher standard deviation (up to 40% in simulations). The two parameter fit with the saturation preparation yielded high robustness towards B0 offsets with a noise performance comparable to that of the two parameter fit. In the volunteer study the T2 values obtained by the pure two parameter fit showed a dependence on the field inhomogeneities, whereas the T2 values from the proposed fitting approach were shown to be insensitive to B0 offsets. The proposed method enabled accurate and precise T2 mapping in the presence of large B1 and B0 offsets. Copyright © 2017 John Wiley & Sons, Ltd.

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

    Directory of Open Access Journals (Sweden)

    C. Gascuel-Odoux

    2010-07-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

  5. Integrating Techniques to Understand the Biological Controls on Redox Conditions at Water Table Interfaces in the Subsurface

    Science.gov (United States)

    Voytek, M. A.; Cozzarelli, I. M.; Kirshtein, J. D.; Bohlke, J.

    2006-05-01

    The Norman Oklahoma Landfill is a closed, unlined municipal landfill in the alluvium of the Canadian River with a leachate plume that extends at least 225m downgradient. The fate and transport of chemical species in the subsurface of this system is largely controlled by changes in the reduction-oxidation (redox) potential which are driven by hydrology, chemistry and microbiology. In this study, we focused on the microbiological and geochemical factors that control redox conditions at the mixing interface of recharge water and aquifer/plume water at two sites (a background site where the contaminant plume rarely reaches the water table and a contaminated site where the plume routinely mixes with recharge water). We examined denitrification, nitrification, iron reduction, sulfate reduction, and methanogenesis using standard microbiological, molecular and geochemical approaches to quantify these processes. Multilevel wells were sampled for geochemistry and core material was collected at the same locations for microbial analyses. The distribution and abundance of specific microbial guilds were determined using Most Probable Number (MPN) analysis and quantitative PCR (qPCR). In general, we see evidence of enhanced microbial activity (i.e. microbially mediated chemical transformations) and microbial abundance at the interfaces due to the increase in oxidized electron acceptors as well as dissolved organic carbon availability from the landfill leachate. For example, water ammonia concentrations decrease near the water table possibly due to nitrification, when ammonium rich leachate water comes into contact with oxygenated recharge. The oxidation of ammonium by nitrification to nitrate is supported by the observation of an increase in nitrogen isotope fractionation resulting in increasing delta-15N values which also correspond to an increase in the abundance of nitrifying bacteria. Based on profiles of the geochemistry and abundance and distribution of specific microbial

  6. Method for the Preparation of Hazard Map in Urban Area Using Soil Depth and Groundwater Level

    Science.gov (United States)

    Kim, Sung-Wook; Choi, Eun-Kyeong; Cho, Jin Woo; Lee, Ju-Hyoung

    2017-04-01

    The hazard maps for predicting collapse on natural slopes consists of a combination of topographic, hydrological, and geological factors. Topographic factors are extracted from DEM, including aspect, slope, curvature, and topographic index. Hydrological factors, such as distance to drainage, drainage density, stream-power index, and wetness index are most important factors for slope instability. However, most of the urban areas are located on the plains and it is difficult to apply the hazard map using the topography and hydrological factors. In order to evaluate the risk of collapse of flat and low slope areas, soil depth and groundwater level data were collected and used as a factor for interpretation. In addition, the reliability of the hazard map was compared with the disaster history of the study area (Gangnam-gu and Yeouido district). In the disaster map of the disaster prevention agency, the urban area was mostly classified as the stable area and did not reflect the collapse history. Soil depth, drainage conditions and groundwater level obtained from boreholes were added as input data of hazard map, and disaster vulnerability increased at the location where the actual collapse points. In the study area where damage occurred, the moderate and low grades of the vulnerability of previous hazard map were 12% and 88%, respectively. While, the improved map showed 2% high grade, moderate grade 29%, low grade 66% and very low grade 2%. These results were similar to actual damage. Keywords: hazard map, urban area, soil depth, ground water level Acknowledgement This research was supported by a Grant from a Strategic Research Project (Horizontal Drilling and Stabilization Technologies for Urban Search and Rescue (US&R) Operation) funded by the Korea Institute of Civil Engineering and Building Technology.

  7. B1-insensitive T2 mapping of healthy thigh muscles using a T2-prepared 3D TSE sequence.

    Science.gov (United States)

    Klupp, Elisabeth; Weidlich, Dominik; Schlaeger, Sarah; Baum, Thomas; Cervantes, Barbara; Deschauer, Marcus; Kooijman, Hendrik; Rummeny, Ernst J; Zimmer, Claus; Kirschke, Jan S; Karampinos, Dimitrios C

    2017-01-01

    To propose a T2-prepared 3D turbo spin echo (T2prep 3D TSE) sequence for B1-insensitive skeletal muscle T2 mapping and compare its performance with 2D and 3D multi-echo spin echo (MESE) for T2 mapping in thigh muscles of healthy subjects. The performance of 2D MESE, 3D MESE and the proposed T2prep 3D TSE in the presence of transmit B1 and B0 inhomogeneities was first simulated. The thigh muscles of ten young and healthy subjects were then scanned on a 3 T system and T2 mapping was performed using the three sequences. Transmit B1-maps and proton density fat fraction (PDFF) maps were also acquired. The subjects were scanned three times to assess reproducibility. T2 values were compared among sequences and their sensitivity to B1 inhomogeneities was compared to simulation results. Correlations were also determined between T2 values, PDFF and B1. The left rectus femoris muscle showed the largest B1 deviations from the nominal value (from 54.2% to 92.9%). Significant negative correlations between T2 values and B1 values were found in the left rectus femoris muscle for 3D MESE (r = -0.72, pvariation (RMSCVs) were equal to 3.5% in T2prep 3D TSE, 2.6% in 3D MESE and 2.4% in 2D MESE. Significant differences between T2 values of 3D sequences (T2prep 3D TSE and 3D MESE) and 2D MESE were found in all muscles with the highest values for 2D MESE (pmuscle T2 mapping.

  8. Water Tables, Evapotranspiration, and Climate Variability: A Decade of Observations From a Semi-Arid Riparian Ecosystem

    Science.gov (United States)

    Thibault, J. R.; Cleverly, J. R.; Dahm, C.

    2009-12-01

    Native (Rio Grande cottonwood) riparian ecosystems in the semi-arid Rio Grande floodplain of central New Mexico are threatened by hydrologic alterations and highly competitive invasive vegetation (saltcedar, Russian olive). Climate change is expected to alter surface runoff in the southwestern United States and exacerbate water scarcity. Depletions are likely to increase in this agricultural riverine corridor downstream of the rapidly growing Albuquerque metropolitan area. Long-term monitoring of shallow alluvial water tables (WTs) and evapotranspiration (ET) in native, non-native, and mixed communities along the river has provided critical information to help understand how water availability affects these ecosystems during a decade of extreme climate variability. Here, we present several observations, with implications for restoration. WTs ranged from several meters depth to flood stage and from relatively stable to highly dynamic, which can influence recruitment of native vegetation and ecosystem functioning. Annual ET declined with deeper WTs across sites, with robust correlations where WTs were dynamic. Riparian communities responded differently to drought cycles and to restorative flooding during peak runoff at the onset of the growing season. Annual ET in a native-dominated system was reduced following removal of non-native understory vegetation, but returned to previous levels when regrowth was left unmanaged. Long-term data are valuable assets that can help optimize efforts to sustain and restore native ecosystems amid the challenges of a changing climate.

  9. The interplay between rainfall infiltration depth, rooting depth and water table depth in regulating Amazon evapotranspiration (ET)

    Science.gov (United States)

    Miguez-Macho, Gonzalo; Fan, Ying; Dominguez, Francina

    2017-04-01

    Plants link the subsurface to the atmosphere via water and carbon fluxes and are therefore a key player in climate. The Amazon, one of Earth's largest ecosystems, is an important climate regulator. As a large source of evapotranspiration, it has significant influence on regional and remote precipitation dynamics. For its equatorial position, it impacts significantly the global climate engine. The Amazon receives abundant annual rainfall but parts of it experience a multi-month dry season. Here we elucidate the interplay among three hydrological depths: precipitation infiltration depth, root water uptake-depth, and the water table depth in regulating dry-season ET, using inverse modeling based on observed productivity, ERA Interim reanalysis atmosphere, and a novel integrated soil-surface-groundwater model with dynamic root uptake to meet the transpiration demand. We perform high-resolution ( 1km) multi-year simulations over the region, with shallow soil, deep soil, with and without groundwater, with and without dynamic rooting depth; attempting to tease out these components. The results demonstrate the strong interactions among the three depths and what each factor does in regulating dry season ET, shedding light on how future global change may preferentially impact Amazon ecosystem functioning.

  10. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

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

    Science.gov (United States)

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

    2012-04-01

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

  12. How to prepare a road map for the management of plastic waste

    DEFF Research Database (Denmark)

    Dorland, Jens; Jørgensen, Michael Søgaard; Skovgaard, Mette

    This paper presents the results of Plastic Zero with the hope to inspire further action to enhance plastic resource-efficiency. It is meant as a source of inspiration on how to make a road map in a similar project. The process has given us various experiences and this guideline on how to make...

  13. How to prepare a road map for the management of plastic waste

    DEFF Research Database (Denmark)

    Dorland, Jens; Jørgensen, Michael Søgaard; Skovgaard, Mette

    This paper presents the results of Plastic Zero with the hope to inspire further action to enhance plastic resource-efficiency. It is meant as a source of inspiration on how to make a road map in a similar project. The process has given us various experiences and this guideline on how to make...

  14. Analysis of spatial-temporal patterns of water table change as a tool for conjunctive water management in the Upper Central Plain of the Chao Phraya River Basin, Thailand

    Science.gov (United States)

    Vasconcelos, Vitor Vieira; Koontanakulvong, Sucharit; Suthidhummajit, Chokchai; Junior, Paulo Pereira Martins; Hadad, Renato Moreira

    2014-11-01

    A sustainable strategy for conjunctive water management must include information on the temporal and spatial availability of this natural resource. Because of water shortages in the dry seasons, farmers on the Upper Plain of the Chao Phraya River basin, Thailand, are increasingly using groundwater to meet their irrigation needs. To evaluate the possibilities of conjunctive water management in the area, the spatial-temporal changes in the water table of the Younger Terrace Aquifer were investigated. First, a regional geomorphological map based on field surveys, remote sensing and previous environmental studies was developed. Then, the well data were analyzed in relation to rainfall, streamflow, yield and pumpage, and the data were interpolated using geostatistical techniques. The results were analyzed via integrated zoning based on color theory as applied to multivariate visualization. The analysis results indicate areas that would be more suitable for groundwater extraction in a conjunctive management framework with regard to the natural hydrogeological processes and the effects of human interaction. The kriging results were compared with the geomorphological map, and the geomorphological areas exhibit distinct hydrogeological patterns. The western fans exhibit the best potential for the expansion of conjunctive use, whereas the borders of the northern fans exhibit the lowest potential.

  15. Analysis of spatial-temporal patterns of water table change as a tool for conjunctive water management in the Upper Central Plain of the Chao Phraya River Basin, Thailand

    Science.gov (United States)

    Vasconcelos, Vitor Vieira; Koontanakulvong, Sucharit; Suthidhummajit, Chokchai; Junior, Paulo Pereira Martins; Hadad, Renato Moreira

    2017-03-01

    A sustainable strategy for conjunctive water management must include information on the temporal and spatial availability of this natural resource. Because of water shortages in the dry seasons, farmers on the Upper Plain of the Chao Phraya River basin, Thailand, are increasingly using groundwater to meet their irrigation needs. To evaluate the possibilities of conjunctive water management in the area, the spatial-temporal changes in the water table of the Younger Terrace Aquifer were investigated. First, a regional geomorphological map based on field surveys, remote sensing and previous environmental studies was developed. Then, the well data were analyzed in relation to rainfall, streamflow, yield and pumpage, and the data were interpolated using geostatistical techniques. The results were analyzed via integrated zoning based on color theory as applied to multivariate visualization. The analysis results indicate areas that would be more suitable for groundwater extraction in a conjunctive management framework with regard to the natural hydrogeological processes and the effects of human interaction. The kriging results were compared with the geomorphological map, and the geomorphological areas exhibit distinct hydrogeological patterns. The western fans exhibit the best potential for the expansion of conjunctive use, whereas the borders of the northern fans exhibit the lowest potential.

  16. Incision history of Glenwood Canyon, Colorado, USA, from the uranium-series analyses of water-table speleothems

    Directory of Open Access Journals (Sweden)

    Victor J. Polyak

    2013-09-01

    Full Text Available Uranium-series analyses of water-table-type speleothems from Glenwood Cavern and “cavelets” near the town of Glenwood Springs, Colorado, USA, yield incision rates of the Colorado River in Glenwood Canyon for the last ~1.4 My. The incision rates, calculated from dating cave mammillary and cave folia calcite situated 65 and 90 m above the Colorado River, are 174 ± 30 m/My for the last 0.46 My and 144 ± 30 m/My for the last 0.62 My, respectively. These are consistent with incision rates determined from nearby volcanic deposits. In contrast, δ234U model ages (1.39 ± 0.25 My; 1.36 ± 0.25 My; and 1.72 ± 0.25 My from three different samples of mammillary-like subaqueous crust collected from Glenwood Cavern, 375 m above the Colorado River, yield incision rates of 271 +58/-41 m/My, 277 +61/-42 m/ My, and 218 +36/-27 m/My. These data suggest a relatively fast incision rate between roughly 3 and 1 Ma. The onset of Pleistocene glaciation may have influenced this rate by increasing precipitation on the Colorado Plateau starting at 2.5 Ma. Slowing of incision just before 0.6 Ma could be related to the change in frequency of glacial cycles from 40 to 100 kyr in the middle Pleistocene. This interpretation would suggest that the cutting power of the Colorado River prior to 3 Ma was smaller. An alternative interpretation involving tectonic activity would invoke an episode of fast uplift in the Glenwood Canyon region from 3 to 1 Ma.

  17. Modeling impacts of changes in temperature and water table on C gas fluxes in an Alaskan peatland

    Science.gov (United States)

    Deng, Jia; Li, Changsheng; Frolking, Steve

    2015-07-01

    Northern peatlands have accumulated a large amount of organic carbon (C) in their thick peat profile. Climate change and associated variations in soil environments are expected to have significant impacts on the C balance of these ecosystems, but the magnitude is still highly uncertain. Verifying and understanding the influences of changes in environmental factors on C gas fluxes in biogeochemical models are essential for forecasting feedbacks between C gas fluxes and climate change. In this study, we applied a biogeochemical model, DeNitrification-DeComposition (DNDC), to assess impacts of air temperature (TA) and water table (WT) on C gas fluxes in an Alaskan peatland. DNDC was validated against field measurements of net ecosystem exchange of CO2 (NEE) and CH4 fluxes under manipulated surface soil temperature and WT conditions in a moderate rich fen. The validation demonstrates that DNDC was able to capture the observed impacts of the manipulations in soil environments on C gas fluxes. To investigate responses of C gas fluxes to changes in TA and soil water condition, we conducted a series of simulations with varying TA and WT. The results demonstrate that (1) uptake rates of CO2 at the site were reduced by either too colder or warmer temperatures and generally increased with increasing soil moisture; (2) CH4 emissions showed an increasing trend as TA increased or WT rose toward the peat surface; and (3) the site could shift from a net greenhouse gas (GHG) sink into a net GHG source under some warm and/or dry conditions. A sensitivity analysis evaluated the relative importance of TA and WT to C gas fluxes. The results indicate that both TA and WT played important roles in regulating NEE and CH4 emissions and that within the investigated ranges of the variations in TA and WT, changes in WT showed a greater impact than changes in TA on NEE, CH4 fluxes, and net C gas fluxes at the study fen.

  18. Modelling effects of seasonal variation in water table depth on net ecosystem CO2 exchange of a tropical peatland

    Directory of Open Access Journals (Sweden)

    M. Mezbahuddin

    2013-08-01

    Full Text Available Seasonal variation in water table depth (WTD determines the balance between aggradation and degradation of tropical peatlands. Longer dry seasons together with human interventions (e.g. drainage can cause WTD drawdowns making tropical peatland C storage highly vulnerable. Better predictive capacity for effects of WTD on net CO2 exchange is thus essential to guide conservation of tropical peat deposits. Mathematical modelling of basic eco-hydrological processes under site-specific conditions can provide such predictive capacity. We hereby deploy a mathematical model ecosys to study effects of seasonal variation in WTD on net ecosystem productivity (NEP of an Indonesian peatland. We simulated lower NEPs (~ –2 g C m–2 d–1 during rainy seasons with shallow WTD, higher NEPs (~ +1 g C m–2 d–1 during early dry seasons with intermediate WTD and again lower NEPs (~ –4 g C mm–2 d–1 during late dry seasons with deep WTD during 2002–2005. These values were corroborated by regressions (P 2 fluxes which yielded R2 > 0.8, intercepts approaching 0 and slopes approaching 1. We also simulated a gradual increase in annual NEPs from 2002 (−609 g C m–2 to 2005 (−373 g C m–2 with decreasing WTD which was corroborated by EC-gap filled annual NEP estimates. These WTD effects on NEP were modelled from basic eco-hydrological processes including microbial and root oxidation-reduction reactions driven by soil and root O2 transport and uptake which in turn drove soil and plant C, N and P transformations within a soil-plant-atmosphere water transfer scheme driven by water potential gradients. This modelling should therefore provide a predictive capacity for WTD management programs to reduce tropical peat degradation.

  19. Modelling Effects of Water Table Depth Variations on Net Ecosystem CO2 Exchange of a Western Canadian Peatland

    Science.gov (United States)

    Mezbahuddin, S.; Grant, R. F.; Flanagan, L. B.

    2014-12-01

    Water table depth (WTD) is one of the key drivers affecting aggradation and degradation of peatlands. Variations in WTD can alter the balance between gross primary productivity (GPP) and ecosystem respiration (Re) and so cause a peatland to change between a sink and a source of carbon. Process based mathematical modelling can provide insights on WTD-net ecosystem productivity (NEP) interactions over peatlands. We deployed a process-based ecosystem model ecosys to examine the WTD effects on variations in NEP of a fen peatland in Alberta, Canada. Our modelled results showed that a growing season (May-August) WTD drawdown of ~0.3m from 2004-2007 caused more rapid decomposition in deeper peat layers so that Re increased by ~180 g C m-2 growing season -1. However, similar increase in GPP (~ 170 g C m-2 growing season -1) under deeper WTD condition due to more rapid microbial and root growth, and hence more rapid mineralization and nutrient uptake, left no net effect of WTD drawdown on NEP. The modelled ecosystem was overall a large sink of C (~ 100 g C m-2 yr-1) over the study period of 2004-2009. However, gradually diminishing GPP by ~ 70 g C m-2 growing season -1 with progressively deeper WTD during 2008-2009 indicated that further drawdown of WTD could alter the source sink status of these peatlands. These modelled results were corroborated against hourly eddy covariance (EC) net CO2 fluxes, latent heat and sensible heat fluxes (R2~0.75, a→0, b→1); and annual estimates of EC-gap filled NEP and partitioned GPP and Re over the site from 2004-2009. Our findings indicated the needs for coupling of soil-plant-atmosphere schemes for gases, water, energy, carbon and nutrients in models to adequately simulate WTD effects on peatland C stocks.

  20. Comparative Education on the Map of Teacher Preparation Programme in Kuwait

    Science.gov (United States)

    Hamad, Al Rashid

    2013-01-01

    Comparative education represents one of the main topics included in teacher preparation programmes in most countries. This subject is critical for future teachers because it represents a window through which learners can look at other educational systems and see how they are managed and what sort of policies and educational philosophies are used.…

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

    Science.gov (United States)

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

    2017-02-01

    Climate change is likely to significantly affect the hydrology, ecology, and ecosystem function of peatlands, with potentially important but unclear impacts on mercury mobility within and transport from peatlands. Using a full-factorial mesocosm approach, we investigated the potential impacts on mercury mobility of water table regime changes (high and low) and vegetation community shifts (sedge-dominated, Ericaceae-dominated, or unmanipulated control) in peat monoliths at the PEATcosm mesocosm facility in Houghton, Michigan. Lower and more variable water table regimes and the loss of Ericaceae shrubs act significantly and independently to increase both total Hg and methylmercury concentrations in peat pore water and in spring snowmelt runoff. These differences are related to enhanced peat decomposition and internal regeneration of electron acceptors which are more strongly related to water table regime than to plant community changes. Loss of Ericaceae shrubs and an increase in sedge cover may also affect Hg concentrations and mobility via oxygen shuttling and/or the provision of labile root exudates. Altered hydrological regimes and shifting vegetation communities, as a result of global climate change, are likely to enhance Hg transport from peatlands to downstream aquatic ecosystems.

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

    Science.gov (United States)

    Jorgensen, D.G.; Signor, D.C.; Imes, J.L.

    1989-01-01

    One method of modeling multiple sources and sinks is to determine the net recharge per cell. For example, for a model cell containing both a sink and recharge through the water table, the amount of recharge should be reduced by the ratio of the area of influence of the sink within the cell to the area of the cell. The reduction is the intercepted portion of the recharge. In a multilayer model this amount is further reduced by a proportion factor, which is a function of the depth of the flow lines from the water table boundary to the internal sink. A gaining section of a stream is a typical sink. The aquifer contribution to a gaining stream can be conceptualized as having two parts; the first part is the intercepted lateral flow from the water table and the second is the flow across the streambed due to differences in head between the water level in the stream and the aquifer below. The amount intercepted is a function of the geometry of the cell, but the amount due to difference in head across the stream bed is largely independent of cell geometry. -from Authors

  3. Reducing nitrogen leaching losses from paddy field under water-saving irrigation by water table control%控制地下水位减少节水灌溉稻田氮素淋失

    Institute of Scientific and Technical Information of China (English)

    和玉璞; 张展羽; 徐俊增; 杨士红; 洪大林

    2014-01-01

    Effects of controlled drainage (CD) on nitrogen leaching losses from paddy field under controlled irrigation (CI) were investigated. Water table control levels were managing with the use of a lysimeter equipped with an automatic water table control system. Three drainage treatments were implemented, namely, controlled water table 1, controlled water table 2, and controlled water table 3. For controlled water table 1, the water table control levels were adjusted daily based on the actual water table depths that were measured by using a water table observation well. Water table control levels in controlled water table 2 were controlled based on the rice root zone depths in different stages according to the water table management that was tested in the humid regions of Eastern Canada and Midwestern United States. For controlled water table 3, the water table control levels in different stages were selected based on previous studies in paddy field of Southeast China. The water table control levels in the later tillering stage and milk stage were also adjusted depending on the characteristics of rice growth and cultivation needs. Experiments were conducted in nine drainage type lysimeters with a mobile shelter and gallery. Each lysimeter had an area of 2.5 m × 2 m and a depth of 1.3 m. Influence of rainfall was avoided using the mobile shelter to strictly regulate the soil moisture in CI. Each lysimeter was individually irrigated and drained using a pipe installed with a water meter and a tube (40 mm in inner diameter) installed at 1.2 m below the soil surface, respectively. Subsurface drainage was conducted based on the water table control levels by using an automatic water table control system, which was installed on each drain tube in the gallery. Subsurface drainage water were collected twice at 2d intervals after each fertilizer application followed by 4d intervals. A 7d sampling interval was used during the rest time. NH4+–N and NO3−–N concentrations in the

  4. Synchronic Coronal Hole Mapping Using Multi-instrument EUV Images: Data Preparation and Detection Method

    Science.gov (United States)

    Caplan, R. M.; Downs, C.; Linker, J. A.

    2016-05-01

    We describe a method for the automatic mapping of coronal holes (CHs) using simultaneous multi-instrument EUV imaging data. Synchronized EUV images from STEREO/EUVI A and B 195 Å and SDO/AIA 193 Å are preprocessed, including point-spread function deconvolution and the application of data-derived intensity corrections which account for center-to-limb variations (limb brightening) and inter-instrument intensity normalization. We systematically derive a robust limb-brightening correction that takes advantage of unbiased long-term averages of data and respects the physical nature of the problem. The new preprocessing greatly assists in CH detection, allowing for the use of a simplified variable-connectivity, two-threshold region-growing image segmentation algorithm to obtain consistent detection results. We generate synchronic EUV and CH maps, and show a preliminary analysis of CH evolution. Several data and code products are made available to the community (www.predsci.com/chd): for the period of this study (2010 June 10 to 2014 August 18), we provide synchronic EUV and CH map data at 6 hr cadence, data-derived limb-brightening corrections for STEREO/EUVI A and B 195 Å and SDO/AIA 193 Å, and inter-instrument correction factors to equate their intensities. We also provide the CH image segmentation code module (ezseg) implemented in both FORTRAN-OpenMP and GPU-accelerated C-CUDA. A complete implementation of our CH detection pipeline in the form of a ready-to-use MATLAB driver script euv2chm utilizing ezseg is also made available.

  5. Synchronic coronal hole mapping using multi-instrument EUV images: Data preparation and detection method

    CERN Document Server

    Caplan, R M; Linker, J L

    2015-01-01

    A method for the automatic mapping of coronal holes (CH) using simultaneous multi-instrument EUV imaging data is described. Synchronized EUV images from STEREO/EUVI A\\&B 195\\AA\\ and SDO/AIA 193\\AA\\ undergo preprocessing steps that include PSF-deconvolution and the application of data-derived intensity corrections that account for center-to-limb variations (limb-brightening) and inter-instrument intensity normalization. A systematic approach is taken to derive a robust limb-brightening correction technique that takes advantage of unbiased long-term averages of data and respects the physical nature of the problem. The new preprocessing greatly assists in CH detection, allowing for the use of a simplified variable-connectivity two-threshold region growing image segmentation algorithm to obtain consistent detection results. Some examples of the generated synchronic EUV and CH maps are shown, as well as preliminary analysis of CH evolutions. Several data and code products are made available to the community ({...

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

    Science.gov (United States)

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

    2017-02-01

    Rapid climate change and intensified human activities have resulted in water table lowering (WTL) and enhanced nitrogen (N) deposition in Tibetan alpine wetlands. These changes may alter the magnitude and direction of greenhouse gas (GHG) emissions, affecting the climate impact of these fragile ecosystems. We conducted a mesocosm experiment combined with a metagenomics approach (GeoChip 5.0) to elucidate the effects of WTL (-20 cm relative to control) and N deposition (30 kg N ha(-1)  yr(-1) ) on carbon dioxide (CO2 ), methane (CH4 ) and nitrous oxide (N2 O) fluxes as well as the underlying mechanisms. Our results showed that WTL reduced CH4 emissions by 57.4% averaged over three growing seasons compared with no-WTL plots, but had no significant effect on net CO2 uptake or N2 O flux. N deposition increased net CO2 uptake by 25.2% in comparison with no-N deposition plots and turned the mesocosms from N2 O sinks to N2 O sources, but had little influence on CH4 emissions. The interactions between WTL and N deposition were not detected in all GHG emissions. As a result, WTL and N deposition both reduced the global warming potential (GWP) of growing season GHG budgets on a 100-year time horizon, but via different mechanisms. WTL reduced GWP from 337.3 to -480.1 g CO2 -eq m(-2) mostly because of decreased CH4 emissions, while N deposition reduced GWP from 21.0 to -163.8 g CO2 -eq m(-2) , mainly owing to increased net CO2 uptake. GeoChip analysis revealed that decreased CH4 production potential, rather than increased CH4 oxidation potential, may lead to the reduction in net CH4 emissions, and decreased nitrification potential and increased denitrification potential affected N2 O fluxes under WTL conditions. Our study highlights the importance of microbial mechanisms in regulating ecosystem-scale GHG responses to environmental changes.

  7. Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

    Directory of Open Access Journals (Sweden)

    J. Järveoja

    2015-10-01

    Full Text Available Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C and greenhouse gas (GHG exchanges is still limited. The aim of this study was to investigate the impact of contrasting water table levels (WTL on the annual C and GHG balances of restoration treatments with high (Res-H and low (Res-L WTL relative to an unrestored bare peat (BP site. Measurements of carbon dioxide (CO2, methane (CH4 and nitrous oxide (N2O fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in Res-H relative to Res-L. Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in Res-L compared to Res-H. However, the means of the measured net ecosystem CO2 exchanges (NEE were not significantly different between Res-H and Res-L. Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges in Res-H and Res-L, respectively. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, Res-H, Res-L and BP were C sources of 111, 103 and 268 g C m−2 yr−1 and had positive GHG balances of 4.1, 3.8 and 10.2 t CO2 eq ha−1 yr−1, respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments three years following restoration. However, the C and GHG balances in Res-H and Res-L were considerably lower than in BP owing to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative

  8. Carbon dioxide flux and net primary production of a boreal treed bog: responses to warming and water table manipulations

    Science.gov (United States)

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

    2014-09-01

    Mid-latitude treed bogs are significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites; control, recent (1-3 years; experimental) and older drained (10-13 years; drained) with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and tree root respiration (Rr) (across hummock-hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011-2013. The carbon (C) balance was calculated by adding net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to driest and warmest 2013, The control site was a~C sink of 92, 70 and 76 g m-2, experimental site was a C source of 14, 57 and 135 g m-2, and drained site was a progressively smaller source of 26, 23 and 13 g m-2, respectively. Although all microforms at the experimental site had large net CO2 emissions, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) at the hummocks and lichens at the hollows leading to the highest CO2 uptake at drained hummocks and significant losses at hollows. The tree NPP was highest at the drained site. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ∼1 °C and differential air warming of ∼6 °C (at mid-day full sun) across the study years. Warming significantly enhanced the shrub growth and CO2 sink function of the drained hummocks (exceeding the cumulative respiration losses at hollows induced by the lowered water level × warming). There was an interaction of water level with warming across hummocks that resulted in largest net CO2 uptake at warmed drained hummocks. Thus in 2013, the warming treatment enhanced the

  9. Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

    Science.gov (United States)

    Järveoja, Järvi; Peichl, Matthias; Maddison, Martin; Soosaar, Kaido; Vellak, Kai; Karofeld, Edgar; Teemusk, Alar; Mander, Ülo

    2016-05-01

    Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C) and greenhouse gas (GHG) exchanges is still limited. The aim of this study was to investigate the impact of contrasting mean water table levels (WTLs) on the annual C and GHG balances of restoration treatments with high (ResH) and low (ResL) WTL relative to an unrestored bare peat (BP) site. Measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in ResH relative to ResL. Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in ResL compared to ResH. However, the means of the measured net ecosystem CO2 exchanges (NEE) were not significantly different between ResH and ResL. Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, ResH, ResL and BP were C sources of 111, 103 and 268 g C m-2 yr-1 and had positive GHG balances of 4.1, 3.8 and 10.2 t CO2 eq ha-1 yr-1, respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments 3 years following restoration. However, the C and GHG balances in ResH and ResL were considerably lower than in BP due to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative climate impacts of abandoned peat extraction areas.

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

    Directory of Open Access Journals (Sweden)

    Craig F. Drury

    2001-01-01

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

  11. Permeability mapping in porous media by magnetization prepared centric-scan SPRITE

    Science.gov (United States)

    Romanenko, Konstantin V.; Balcom, Bruce J.

    2011-02-01

    The ability of porous media to transmit fluids is commonly referred to as permeability. The concept of permeability is central for hydrocarbon recovery from petroleum reservoirs and for studies of groundwater flow in aquifers. Spatially resolved measurements of permeability are of great significance for fluid dynamics studies. A convenient concept of local Darcy's law is suggested for parallel flow systems. The product of porosity and mean velocity images in the plane across the average flow direction is directly proportional to permeability. Single Point Ramped Imaging with T 1 Enhancement (SPRITE) permits reliable quantification of local fluid content and flow in porous media. It is particularly advantageous for reservoir rocks characterized by fast magnetic relaxation of a saturating fluid. Velocity encoding using the Cotts pulsed field gradient scheme improves the accuracy of measured flow parameters. The method is illustrated through measurements of 2D permeability maps in a capillary bundle, glass bead packs and composite sandstone samples.

  12. Preparation and analysis of spermatocyte meiotic pachytene bivalents of pigs for gene mapping

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Well-spread meiotic pachytene bivalents were obtained by using the prolonged hypotonic treatment com-bined with high chloroform Carnory's fixative solution from cells of the testes of domestic pigs. Comparisonin the division index and length of pachytenc bivalents with metaphase chromosomes showed that those ofthe former are 5 times higher and 3.42(1.87-5.98) times longer than those of the latter. Comparative studieson chromomere maps of bivalents and mitotic chromosomal G-bands were conducted by using the chromo-some 12 as a example. Sex vesicle and various shapes of synaptic sex chromosomes have been observed.Two-color PRimed IN Situ (PRINS) labeling has been conducted successfully on pachytene bivalents of pigs.

  13. Liquefaction Hazard Maps for Three Earthquake Scenarios for the Communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos, Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale, Northern Santa Clara County, California

    Science.gov (United States)

    Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.

    2008-01-01

    Maps showing the probability of surface manifestations of liquefaction in the northern Santa Clara Valley were prepared with liquefaction probability curves. The area includes the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale. The probability curves were based on complementary cumulative frequency distributions of the liquefaction potential index (LPI) for surficial geologic units in the study area. LPI values were computed with extensive cone penetration test soundings. Maps were developed for three earthquake scenarios, an M7.8 on the San Andreas Fault comparable to the 1906 event, an M6.7 on the Hayward Fault comparable to the 1868 event, and an M6.9 on the Calaveras Fault. Ground motions were estimated with the Boore and Atkinson (2008) attenuation relation. Liquefaction is predicted for all three events in young Holocene levee deposits along the major creeks. Liquefaction probabilities are highest for the M7.8 earthquake, ranging from 0.33 to 0.37 if a 1.5-m deep water table is assumed, and 0.10 to 0.14 if a 5-m deep water table is assumed. Liquefaction probabilities of the other surficial geologic units are less than 0.05. Probabilities for the scenario earthquakes are generally consistent with observations during historical earthquakes.

  14. Preparation of Residual Gravity Maps for the Southern Cascade Mountains, Washington Using Fourier Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dishberger, Debra McLean

    1983-04-01

    This report represents a continuation of gravity work in the Cascade Mountains of Washington supported by the Division of Geology and Earth Resources since 1974. The purpose of this research has been collection of baseline gravity data for use in geothermal resource evaluation. Results of the Division's gravity studies to date are given in Danes and Phillips (1983a, 1983b). One of the problems encountered when analyzing gravity data is distinguishing between those parts of the data that represent geologic structures of interest, and those that do not. In many cases, the features of interest are relatively small, near-surface features, such as those sought in mineral, petroleum, or geothermal exploration. Gravity anomalies caused by such structures may be distorted or masked by anomalies caused by larger, deeper geologic structures. Gravity anomalies caused by relatively shallow, small geologic structures are termed residual anomalies. Those due to broad, deep-seated features can be described as regional anomalies. The purpose of this report is to describe a Fourier analysis method for separating residual and regional gravity anomalies from a complete Bouguer gravity anomaly field. The technique has been applied to gravity data from the Southern Cascade Mountains, Washington. Residual gravity anomaly maps at a scale of 1:250,000 are presented for various regional wavelength filters, and a power spectrum of the frequency components in the South Cascade gravity data is displayed. No attempt is made to interpret the results of this study in terms of geologic structures.

  15. Microbial and metabolic profiling reveal strong influence of water table and land-use patterns on classification of degraded tropical peatlands

    Science.gov (United States)

    Mishra, S.; Lee, W. A.; Hooijer, A.; Reuben, S.; Sudiana, I. M.; Idris, A.; Swarup, S.

    2014-04-01

    Tropical peatlands from southeast Asia are undergoing extensive drainage, deforestation and degradation for agriculture and human settlement purposes. This is resulting in biomass loss and subsidence of peat from its oxidation. Molecular profiling approaches were used to understand the relative influences of different land-use patterns, hydrological and physicochemical parameters on the state of degraded tropical peatlands. As microbial communities play a critical role in biogeochemical cascades in the functioning of peatlands, we used microbial and metabolic profiles as surrogates of community structure and functions, respectively. Profiles were generated from 230 bacterial 16 S rDNA fragments and 145 metabolic markers of 46 samples from 10 sites, including those from above and below water table in a contiguous area of 48 km2 covering five land-use types. These were degraded forest, degraded land, oil palm plantation, mixed crop plantation and settlements. Bacterial profiles were most influenced by variations in water table and land-use patterns, followed by age of drainage and peat thickness in that order. Bacterial profiling revealed differences in sites, based on the duration and frequency of water table fluctuations and on oxygen availability. Mixed crop plantations had the most diverse bacterial and metabolic profiles. Metabolic profiling, being closely associated with biogeochemical functions, could distinguish communities not only based on land-use types but also their geographic locations, thus providing a finer resolution than bacterial profiles. Agricultural inputs, such as nitrates, were highly associated with bacterial community structure of oil palm plantations, whereas phosphates and dissolved organic carbon influenced those from mixed crop plantations and settlements. Our results provide a basis for adopting molecular marker-based approaches to classify peatlands and determine relative importance of factors that influence peat functioning. Our

  16. Contrasting responses of growing season ecosystem CO2 exchange to variation in temperature and water table depth in two peatlands in northern Alberta, Canada

    Science.gov (United States)

    Adkinson, Angela C.; Syed, Kamran H.; Flanagan, Lawrence B.

    2011-03-01

    The large belowground carbon stocks in northern peatland ecosystems are potentially susceptible to release because of the expected differential responses of photosynthesis and respiration to climate change. This study compared net ecosystem CO2 exchange (NEE) measured using the eddy covariance technique at two peatland sites in northern Alberta, Canada, over three growing seasons (May-October). We observed distinct differences between the poor fen (Sphagnum moss dominated) and extreme-rich fen (Carex sedge dominated) sites for their responses of NEE to interannual variation in temperature and water table depth. The rates of growing season cumulative NEE at the poor fen were very similar among the three study years with an average (± standard deviation) of -110.1 ± 0.5 g C m-2 period-1. By contrast, the growing season cumulative NEE at the extreme-rich fen varied substantially among years (-34.5, -153.5, and -41.8 g C m-2 period-1 in 2004, 2005, and 2006, respectively), and net uptake of CO2 was lower (on average) than at the poor fen. Consistent with the eddy covariance measurements, analysis of 210Pb-dated peat cores also showed higher recent net rates of carbon accumulation in the poor fen than in the rich fen. Warm spring temperatures and sufficient water availability during the growing season resulted in the highest-magnitude ecosystem photosynthesis and NEE at the extreme-rich fen in 2005. Cool spring temperatures limited photosynthesis at the extreme-rich fen in 2004, while reduced water availability (lower water table) in 2006 constrained photosynthetic capacity relative to 2005, despite the warmer spring and summer temperatures in 2006. The combination of contrasting plant functional types and different peat water table features at our two study sites meant that the poor fen showed a reduced response of ecosystem CO2 exchange to environmental variation compared to the extreme-rich fen.

  17. Greenhouse gas emissions of drained fen peatlands in Belarus are controlled by water table, land use, and annual weather conditions

    Science.gov (United States)

    Burlo, Andrei; Minke, Merten; Chuvashova, Hanna; Augustin, Jürgen; Hoffmann, Mathias; Narkevitch, Ivan

    2014-05-01

    Drainage of peatlands causes strong emission of the greenhouse gases (GHG) CO2 and N2O, sometimes combined with a weak CH4 uptake. In Belarus drained peatlands occupy about 1505000 ha or more than 7.2 % of the country area. Joosten (2009) estimates CO2 emission from degraded peatlands in Belarus as 41.3 Mt yr-1 what equals to 47 % of total anthropogenic greenhouse gases (GHGs) emission of country in 2011. However, it could not be checked if these numbers are correct since there are no GHG measurements on these sites up to now. Therefore we studied the GHG emissions with the closed chamber approach in four peatlands situated in central and southern Belarus over a period from August 2010 to August 2012. The measurements comprised eight site types representing different water level conditions, and ranging from grassland and arable land over abandoned fields and peat cuts to near-natural sedge fens. Fluxes of CH4 and N2O were determined using the close-chamber approach every second week in snow free periods and every fourth week during winter time. The annual emissions were calculated based on linear interpolation. Carbon dioxide exchange was measured with transparent and opaque chambers every 3-4 weeks and the annual net ecosystem exchange (NEE) was modeled according to Drösler (2005). Most of the drained sites were sources of CO2 in both years. NEE increased with lower mean annual water table level. The highest NEE value (1263.5 g CO2-C m-1yr-1) was observed at the driest site of the study; an abandoned fen formerly used for agriculture. In contrast, a former peat extraction site with moist peat and small Pinus sylvestris tress were sinks of CO2 with uptake to 389.6 g CO2-C m-1yr-1. The highest N2O emissions were recorded at a drained agricultural fen with mean annual rates of up to 2347 mg N2O-N m-2 yr-1. Significant fluxes of CH4 (15 g CH4C m-2 h-1) were observed only at the near-natural site in the first year of investigation when precipitation and the mean water

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

    Directory of Open Access Journals (Sweden)

    P. Straková

    2011-09-01

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

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

  19. Social dataset analysis and mapping tools for Risk Perception: resilience, people preparation and communication tools

    Science.gov (United States)

    Peters-Guarin, Graciela; Garcia, Carolina; Frigerio, Simone

    2010-05-01

    Perception has been identified as resource and part of the resilience of a community to disasters. Risk perception, if present, may determine the potential damage a household or community experience. Different levels of risk perception and preparedness can influence directly people's susceptibility and the way they might react in case of an emergency caused by natural hazards. In spite of the profuse literature about risk perception, works to spatially portray this feature are really scarce. The spatial relationship to danger or hazard is being recognised as an important factor of the risk equation; it can be used as a powerful tool either for better knowledge or for operational reasons (e.g. management of preventive information). Risk perception and people's awareness when displayed in a spatial format can be useful for several actors in the risk management arena. Local authorities and civil protection can better address educational activities to increase the preparation of particularly vulnerable groups of clusters of households within a community. It can also be useful for the emergency personal in order to optimally direct the actions in case of an emergency. In the framework of the Marie Curie Research Project, a Community Based Early Warning System (CBEWS) it's been developed in the Mountain Community Valtellina of Tirano, northern Italy. This community has been continuously exposed to different mass movements and floods, in particular, a large event in 1987 which affected a large portion of the valley and left 58 dead. The actual emergency plan for the study area is composed by a real time, highly detailed, decision support system. This emergency plan contains detailed instructions for the rapid deployment of civil protection and other emergency personal in case of emergency, for risk scenarios previously defined. Especially in case of a large event, where timely reaction is crucial for reducing casualties, it is important for those in charge of emergency

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

    Science.gov (United States)

    Garrido, Marco; Silva, Paola; Acevedo, Edmundo

    2016-01-01

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

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

    Science.gov (United States)

    Garrido, Marco; Silva, Paola; Acevedo, Edmundo

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Marco eGarrido

    2016-03-01

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

  3. WTAQ version 2-A computer program for analysis of aquifer tests in confined and water-table aquifers with alternative representations of drainage from the unsaturated zone

    Science.gov (United States)

    Barlow, Paul M.; Moench, Allen F.

    2011-01-01

    The computer program WTAQ simulates axial-symmetric flow to a well pumping from a confined or unconfined (water-table) aquifer. WTAQ calculates dimensionless or dimensional drawdowns that can be used with measured drawdown data from aquifer tests to estimate aquifer hydraulic properties. Version 2 of the program, which is described in this report, provides an alternative analytical representation of drainage to water-table aquifers from the unsaturated zone than that which was available in the initial versions of the code. The revised drainage model explicitly accounts for hydraulic characteristics of the unsaturated zone, specifically, the moisture retention and relative hydraulic conductivity of the soil. The revised program also retains the original conceptualizations of drainage from the unsaturated zone that were available with version 1 of the program to provide alternative approaches to simulate the drainage process. Version 2 of the program includes all other simulation capabilities of the first versions, including partial penetration of the pumped well and of observation wells and piezometers, well-bore storage and skin effects at the pumped well, and delayed drawdown response of observation wells and piezometers.

  4. Microbial and metabolic profiling reveal strong influence of water table and land-use patterns on classification of degraded tropical peatlands

    Directory of Open Access Journals (Sweden)

    S. Mishra

    2013-08-01

    Full Text Available Tropical peatlands from Southeast Asia are undergoing extensive drainage, deforestation and degradation for agriculture and human settlement purposes. This is resulting in biomass loss and subsidence of peat from its oxidation. Molecular profiling approaches were used to understand the relative influences of different land-use patterns, hydrological and physiochemical parameters on the state of degraded tropical peatlands. As microbial communities play a critical role in biogeochemical cascades in the functioning of peatlands, we used microbial and metabolic profiles as surrogates of community structure and functions, respectively. Profiles were generated from 230 bacterial 16S rDNA fragments and 145 metabolic markers of 46 samples from ten sites, including those from above and below water table in a contiguous area of 48 km2 covering five land-use types. These were degraded forest, degraded land, oil palm plantation, mixed crop plantation and settlements. Bacterial profiles were most influenced by variations in water table and land-use patterns, followed by age of drainage and peat thickness in that order. Bacterial profiling revealed differences in sites, based on the duration and frequency of water table fluctuations and on oxygen availability. Bacterial and metabolic profiles of degraded forest and mixed crop plantations were most diverse compared to other land-use types. Metabolic profiling, being closely associated with biogeochemical functions could distinguish communities not only based on land-use types but also their geographic locations, thus providing a finer resolution than bacterial profiles. Agricultural inputs, such as nitrates were highly associated with bacterial community structure of oil palm plantations, whereas phosphates and dissolved organic carbon influenced those from mixed crop plantations and settlements. Our results provide a basis for adopting molecular marker-based approaches to classify peatlands and determine

  5. An investigation of growing season fluctuations of water table in a forestry-drained Scots pine peatland using weather data and spatial information

    Science.gov (United States)

    Hökkä, Hannu; Haahti, Kersti; Sarkkola, Sakari; Nieminen, Mika; Koivusalo, Harri

    2013-04-01

    Soil water table depth (WTD) is one of the most important factors controlling the net primary production such as tree growth on peatlands. The growing season WTD is known to be dependent on the weather conditions, stand evapotranspiration capacity and drainage structures on drained peatlands. In this study we used modeling approach to investigate how meteorological and spatial variables contribute to variation of the growing season WTD in a drained boreal peatland forest. The study data were collected from a Scots pine (Pinus sylvestris L.) dominated experimental peatland stand drained for forestry purposes 70 years ago in Rovaniemi, northern Finland. Double ditching was used to form ca. 0.5 ha artificial catchment in spring 2006. The spacing between 0.9 m deep ditches was 23 m and peat depth varied from 0.6 m to more than 2 m within the area. For monitoring the WTD, 50 perforated plastic tubes were inserted into the peat and spaced in a regular grid to evenly cover the whole catchment area. WTD was manually monitored from each tube at one or two week intervals during the frost free period (early June - end of October) in 2006 - 2009. To account for the hierarchical structure of the data, the linear mixed model technique was applied to construct a prediction model for the logarithm of the WTD in a tube. Meteorological variables were derived from observations of a weather station located 50 km away. The used meteorological variables were the cumulative precipitation, the precipitation of previous 28 days, cumulative evapotranspiration, and the evapotranspiration of previous 30 days. The spatial parameters were the local stand basal area (sum of tree basal areas within 2 m radius around the tube), the distance of a tube to the nearest ditch, and topography (elevation). The meteorological parameters were most important predictors in the model. The distance to a ditch and the elevation were most important spatial parameters. The relationship between the local stand

  6. Magnetic susceptibility as a proxy for the hydrobiogeochemical cycling of iron within the water table fluctuation zone at hydrocarbon contaminated sites

    Science.gov (United States)

    Atekwana, E. A.; Enright, A.; Atekwana, E. A.; Beaver, C. L.; Rossbach, S.; Slater, L. D.; Ntarlagiannis, D.

    2016-12-01

    Sharp redox gradients are indicative of enhanced biogeochemical activity and occur at or near the water table. Hydrologic forcing drives changes in redox state and oxygen levels, enhancing the elemental cycling of metals, and coupling different biogeochemical cycles. These coupled hydrobiogeochemical cycles are often difficult to study in the field using geochemical and microbial proxies because of direct sampling limitations, the costs associated with these techniques, and because the dynamic nature of these processes complicates the interpretation of single time point measurements, which may not give accurate representations of prevailing conditions. Geophysical techniques can provide both the spatial and temporal resolution needed to elucidate these processes. Here we investigated the use of magnetic susceptibility (c) as a viable proxy for understanding the biogeochemical cycling of iron at several hydrocarbon contaminated sites where active intrinsic bioremediation is occurring. We performed borehole c logging using a Bartington c probe in the field as well as made c measurements on core samples retrieved from the field sites. Our results show the following: (1) in both sulfate-rich and sulfate-poor aquifers, excursions in c are coincident with zones of free product contamination and are limited to the water table fluctuation (smear) zone; (2) c values within the free product plume and contamination source zones are higher compared to values within the dissolved product plume; (3) high c coincides with zones of elevated Fe (II) and Fe (III) concentrations extracted from aquifer solids; and (4) the mixed valence magnetite and greigite were the dominant magnetic minerals. The c excursions are limited to the water table fluctuation zones because fluctuating water level conditions are hot beds for microbial activity due to the steep hydrocarbon and nutrients and consequently redox gradients. High water levels during periods of recharge favor anaerobic conditions

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

    Science.gov (United States)

    Boutt, D. F.

    2011-12-01

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

  8. Effect of ground-water recharge on configuration of the water table beneath sand dunes and on seepage in lakes in the sandhills of Nebraska, U.S.A.

    Science.gov (United States)

    Winter, T.C.

    1986-01-01

    Analysis of water-level fluctuations in about 30 observation wells and 5 lakes in the Crescent Lake National Wildlife Refuge in the sandhills of Nebraska indicates water-table configuration beneath sand dunes in this area varies considerably, depending on the configuration of the topography of the dunes. If the topography of an interlake dunal area is hummocky, ground-water recharge is focused at topographic lows causing formation of water-table mounds. These mounds prevent ground-water movement from topographically high lakes to adjacent lower lakes. If a dune ridge is sharp, the opportunity for focused recharge does not exist, resulting in water-table troughs between lakes. Lakes aligned in descending altitudes, parallel to the principal direction of regional ground-water movement, generally have seepage from higher lakes toward lower lakes. ?? 1986.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-01-01

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

  10. Reading the Water Table: The Interaction between Literacy Practices and Groundwater Management Training in Preparing Farmers for Climate Change in South India

    Science.gov (United States)

    Chavva, Konda Reddy; Smith, Cristine A.

    2012-01-01

    This article focuses on farmers' use of literacy for individual decision-making on crop-water management and crop choices and investigates how farmer participants perceive the usefulness of Farmer Water School (FWS) training. It draws upon a study conducted with farmers of Kurnool district of Andhra Pradesh, India. This study has demonstrated that…

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

    NARCIS (Netherlands)

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

    2000-01-01

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

  12. Benthic Habitat Type Maps of the Oahu Island 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twenty-four habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for...

  13. Benthic Habitat Type Maps of Hawaii Island 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twenty-one Habitat and Zome Maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for...

  14. Benthic Habitat Type Maps of Kauai Island 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Eleven habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal...

  15. Benthic Habitat Type Maps of Molakai 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nine habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal...

  16. Benthic Habitat Type Maps of the Niihau Island 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Four habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal...

  17. Benthic Habitat Type Maps of Lanai 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — FIve habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal...

  18. Benthic Habitat Type Maps of the Maui Island 2000 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Thirteen habitat and zone maps. This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for...

  19. 蒸渗仪地下水位自动平衡系统设计%An automatic balancing system design to ground water table of lysimeter

    Institute of Scientific and Technical Information of China (English)

    郭相平; 陆红飞; 陈盛

    2014-01-01

    为准确保持大田水位与蒸渗仪水位的实时相平,并测定地下水补给量和深层渗漏量,提出了一种蒸渗仪水位自动平衡系统的设计方法。该系统基于连通器原理,并利用水、汞的导电性差异而设计,由3部分组成:淤水位监测装置,包括蒸渗仪和大田的地下水位观测井及连接管;于水位感应和控制装置,由内盛液态汞的U形管以及控制电路组成,能比较大田和蒸渗仪的水位差,并通过电磁继电器打开/关闭供排水电磁阀;盂供(排)水与量测装置,由供水装置、排水装置及其电磁阀和量测装置组成。该系统结构简单,造价低廉,易于维护和管理;初步测试表明,该系统具有较好的控制精度,适于地下水位变化较大的地区使用。%In order to synchronize the water table of a lysimeter with that of farmland, and measure the amount of recharge of groundwater and deep percolation, a design method for an automatic balancing system of the water table of a lysimeter is put forward. Based on the principle of a communicating vessel, and designed according to the electrical conductivity differences between water and mercury, the system consists of three parts:(1) water level detecting equipment, consisting of two observation wells and connecting pipes, (2) a water level sensor and controlling equipment, composed of a U-shape glass filled with mercury and control circuits, which can compare the difference of groundwater level between farmland and a lysimeter, and can switch on/off solenoid valves for water supply and drainage through electromagnetic relays; and (3) various equipment, including water supply and drainage equipment, solenoid valves, and measurement devices. The system is simple in construction, cheap, and easy to maintain and manage. The initial testing results indicate that the system has good accuracy, and is appropriate for application in areas where the water table varies

  20. Water-table contours, directions of ground-water movement, and measurements of inflow to American Falls Reservoir, Southeastern Idaho, April 1984

    Science.gov (United States)

    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

  1. Nutrient load can lead to enhanced CH4 fluxes through changes in vegetation, peat surface elevation and water table depth in ombrotrophic bog

    Science.gov (United States)

    Juutinen, Sari; Bubier, Jill; Larmola, Tuula; Humphreys, Elyn; Arnkil, Sini; Roy, Cameron; Moore, Tim

    2016-04-01

    Atmospheric nitrogen (N) deposition has led to nutrient enrichment in wetlands, particularly in temperate areas, affecting plant community composition, carbon (C) cycling, and microbial dynamics. It is vital to understand the temporal scales and mechanisms of the changes, because peatlands are long-term sinks of C, but sources of methane (CH4), an important greenhouse gas. Rainwater fed (ombrotrophic) bogs are considered to be vulnerable to nutrient loading due to their natural nutrient poor status. We fertilized Mer Bleue Bog, a Sphagnum moss and evergreen shrub-dominated ombrotrophic bog near Ottawa, Ontario, now for 11-16 years with N (NO3 NH4) at 0.6, 3.2, and 6.4 g N m-2 y-1 (~5, 10 and 20 times ambient N deposition during summer months) with and without phosphorus (P) and potassium (K). Treatments were applied to triplicate plots (3 x 3 m) from May - August 2000-2015 and control plots received distilled water. We measured CH4 fluxes with static chambers weekly from May to September 2015 and peat samples were incubated in laboratory to measure CH4 production and consumption potentials. Methane fluxes at the site were generally low, but after 16 years, mean CH4 emissions have increased and more than doubled in high nitrogen addition treatments if P and K input was also increased (3.2 and 6.4 g N m-2yr-1 with PK), owing to drastic changes in vegetation and soil moisture. Vegetation changes include a loss of Sphagnum moss and introduction of new species, typical to minerogenic mires, which together with increased decomposition have led to decreased surface elevation and to higher water table level relative to the surface. The trajectories indicate that the N only treatments may result in similar responses, but only over longer time scales. Elevated atmospheric deposition of nutrients to peatlands may increase loss of C not only due to changes in CO2 exchange but also due to enhanced CH4 emissions in peatlands through a complex suite of feedbacks and interactions

  2. Human Mind Maps

    Science.gov (United States)

    Glass, Tom

    2016-01-01

    When students generate mind maps, or concept maps, the maps are usually on paper, computer screens, or a blackboard. Human Mind Maps require few resources and little preparation. The main requirements are space where students can move around and a little creativity and imagination. Mind maps can be used for a variety of purposes, and Human Mind…

  3. Identification of nitrate long term trends in Loire-Brittany river district (France) in connection with hydrogeological contexts, agricultural practices and water table level variations

    Science.gov (United States)

    Lopez, B.; Baran, N.; Bourgine, B.; Ratheau, D.

    2009-04-01

    The European Union (EU) has adopted directives requiring that Member States take measures to reach a "good" chemical status of water resources by the year 2015 (Water Framework Directive: WFD). Alongside, the Nitrates Directives (91/676/EEC) aims at controlling nitrogen pollution and requires Member States to identify groundwaters that contain more than 50 mg NO3 L-1 or could exceed this limit if preventive measures are not taken. In order to achieve these environmental objectives in the Loire-Brittany river basin, or to justify the non achievement of these objectives, a large dataset of nitrate concentrations (117.056 raw data distributed on 7.341 time-series) and water table level time-series (1.371.655 data distributed on 511 piezometers) is analysed from 1945 to 2007. The 156.700 sq km Loire-Brittany river basin shows various hydrogeological contexts, ranging from sedimentary aquifers to basement ones, with a few volcanic-rock aquifers. The knowledge of the evolution of agricultural practices is important in such a study and, even if this information is not locally available, agricultural practices have globally changed since the 1991 Nitrates Directives. The detailed dataset available for the Loire-Brittany basin aquifers is used to evaluate tools and to propose efficient methodologies for identifying and quantifying past and current trends in nitrate concentrations. Therefore, the challenge of this study is to propose a global and integrated approach which allows nitrate trend identifications for the whole Loire-Brittany river basin. The temporal piezometric behaviour of each aquifer is defined using geostatistical analyse of water table level time-series. This method requires the calculation of an experimental temporal variogram that can be fitted with a theoretical model valid for a large time range. Identification of contrasted behaviours (short term, annual or pluriannual water table fluctuations) allows a systematic classification of the Loire

  4. Groundwater compartmentalisation: a water table height and geochemical analysis of the structural controls on the subdivision of a major aquifer, the Sherwood Sandstone, Merseyside, UK

    Directory of Open Access Journals (Sweden)

    E. A. Mohamed

    2006-01-01

    Full Text Available Compartmentalisation, the subdivision of an aquifer into discrete and relatively isolated units, may be of critical importance for the protection of groundwater although it has been largely ignored in the groundwater literature. The Lower Triassic Sherwood Sandstone, in north west of England, UK, may be a good example of an aquifer that has been compartmentalised by numerous high angle faults with displacements of up to 300 m. The study was initiated to assess the local groundwater flow, the extent of seawater invasion and the controls on recharge in the aquifer and to try to understand whether the aquifer is broken into discrete compartments. Maps and schematic cross-sections of groundwater heads for the years 1993, and 2002 were prepared to trace any structural controls on the groundwater heads across the area. Studying the contour maps and cross sections revealed that: 1 there are substantial differences in groundwater head across some of the NNW-SSE trending faults implying that groundwater flow is strongly limited by faults, 2 an anticline in the east of the area acts as a groundwater divide and 3 the groundwater head seems to follow the topography in some places, although steep changes in groundwater head occur across faults showing that they locally control the groundwater head. The aquifer was thus provisionally subdivided into several hydrogeological sub-basins based on groundwater head patterns and the occurrence of major structural features (faults and a fold. Using groundwater geochemistry data, contour maps of chloride and sulphate concentration largely support the structural sub-division of the area into hydrogeological sub-basins. Scrutiny of groundwater geochemical data, averaged for each sub-basin, confirmed the degree of compartmentalisation and the occurrence of sealed faults. The variation of the geochemical composition of the groundwater not only relates to the different, localised geochemical processes and seawater

  5. An automated on-line multidimensional HPLC system for protein and peptide mapping with integrated sample preparation

    NARCIS (Netherlands)

    Wagner, K.; Miliotis, T.; Marko-Varga, G; Bischoff, Rainer; Unger, K.K.

    2002-01-01

    A comprehensive on-line two-dimensional 2D-HPLC system with integrated sample preparation was developed for the analysis of proteins and peptides with a molecular weight below 20 kDa. The system setup provided fast separations and high resolving power and is considered to be a complementary techniqu

  6. Concentrations of selected trace inorganic constituents and synthetic organic compounds in the water-table aquifers in the Memphis area, Tennessee

    Science.gov (United States)

    McMaster, B.W.; Parks, William Scott

    1988-01-01

    Water quality samples for analysis of selected trace inorganic constituents and synthetic organic compounds were collected from 29 private or observation wells in alluvium and fluvial deposits of Quaternary and Tertiary Age. The alluvium and fluvial deposits are the water table aquifers in the Memphis area. In addition, nine wells were installed in Memphis Light, Gas and Water Division well fields so that samples could be collected and analyzed to characterize the quality of water in the fluvial deposits at these well fields. Samples from seven of these wells (two were dry) were analyzed for major constituents and properties of water as well as for selected trace inorganic constituents and synthetic organic compounds. Analyses of the water from most of the 36 wells sampled indicated ranges in concentration values for the trace inorganic constituents that agreed with those previously known, although some new maximum values were established. The analysis of water from four wells indicated that the water is or may be contaminated. Concentrations of barium (1,400 micrograms/L -- ug/L), strontium (1,100 ug/L), and arsenic (15 ug/L), along with specific conductance (1,420 microsiemens/centimeter--us/cm) were in water from one well in the alluvium. Low concentrations (0.02 to 0.04 ug/L) of the pesticides aldrin, DDT, endosulfan, and perthane were present in water from two wells in the fluvial deposits. Water from one of these wells also contained 1,1,1 trichloroethane (4.4 ug/L). Analysis of water from another well in the fluvial deposits indicated values for specific conductance (1,100 uS/cm), alkalinity (508 milligrams per liter -- mg/L -- as CaCO3), hardness (550 mg/L as CaCO3), chloride (65 mg/L), and barium (240 ug/L) that are high for water from the fluvial deposits. (USGS)

  7. A GRACE-Streamflow Land Surface Model Calibration Approach for Improved Baseflow and Water Table Simulations over the Highly Managed Upper-Nile Basin of East Africa

    Science.gov (United States)

    Nanteza, J.; Lo, M. H.; Wu, R. J.; Thomas, B. F.; Famiglietti, J. S.

    2015-12-01

    Land surface models (LSMs) are useful tools for understanding behaviors of land hydrologic variables at different time and spatial scales. LSM outputs, however, are marked with great uncertainties resulting from the simplified assumptions on the parameterization and processes of the land surface and a poor representation of both the natural and anthropogenic controls on the system. The Upper-Nile basin, over Uganda, Kenya and Tanzania, is one region that is characteristic of significant human controls on streamflow, including Lake Victoria releases. The river Nile flow from Lake Victoria follows apriori rating curves that are not simulated by LSMs. Apart from management practices; the huge storage volume of Lake Victoria also modifies the seasonal characteristics of the Upper-Nile discharge, creating small seasonal variations in stream flow. In this study we calibrate several critical parameters in the Community Land Model (CLM.v4) in a multiobjective framework using total water storage anomalies (∆TWS) from GRACE, observed total runoff (Q) and estimated baseflow (BF) over the Upper-Nile basin. The goal is to improve the CLM parameters so that the model simulates the agreed curve (apriori) streamflow and baseflow with a better accuracy. We demonstrate the significance of improved parametrization by comparing model results of ∆TWS, Q and BF with a combination of insitu and estimated observations. Preliminary results based on RMSE statistics show that with calibration, simulations of ∆TWS, Q and BF achieve higher performance. Further, an improvement in the model's capacity to simulate the water table depth is also evident with the calibration. Such results provide a basis for using CLM for other hydrologic experiments that could guide water resources management in this highly managed basin.

  8. Preparation of an antitumor and antivirus agent: chemical modification of α-MMC and MAP30 from Momordica Charantia L. with covalent conjugation of polyethyelene glycol.

    Science.gov (United States)

    Meng, Yao; Liu, Shuangfeng; Li, Juan; Meng, Yanfa; Zhao, Xiaojun

    2012-01-01

    Alpha-momorcharin (α-MMC) and momordica anti-HIV protein (MAP30) derived from Momordica charantia L. have been confirmed to possess antitumor and antivirus activities due to their RNA-N-glycosidase activity. However, strong immunogenicity and short plasma half-life limit their clinical application. To solve this problem, the two proteins were modified with (mPEG)(2)-Lys-NHS (20 kDa). In this article, a novel purification strategy for the two main type I ribosome-inactivating proteins (RIPs), α-MMC and MAP30, was successfully developed for laboratory-scale preparation. Using this dramatic method, 200 mg of α-MMC and about 120 mg of MAP30 was obtained in only one purification process from 200 g of Momordica charantia seeds. The homogeneity and some other properties of the two proteins were assessed by gradient SDS-PAGE, electrospray ionization quadruple mass spectrometry, and N-terminal sequence analysis as well as Western blot. Two polyethylene glycol (PEG)ylated proteins were synthesized and purified. Homogeneous mono-, di-, or tri-PEGylated proteins were characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The analysis of antitumor and antivirus activities indicated that the serial PEGylated RIPs preserved moderate activities on JAR choriocarcinoma cells and herpes simplex virus-1. Furthermore, both PEGylated proteins showed about 60%-70% antitumor and antivirus activities, and at the same time decreased 50%-70% immunogenicity when compared with their unmodified counterparts. α-MMC and MAP30 obtained from this novel purification strategy can meet the requirement of a large amount of samples for research. Their chemical modification can solve the problem of strong immunogenicity and meanwhile preserve moderate activities. All these findings suggest the potential application of PEGylated α-MMC and PEGylated MAP30 as antitumor and antivirus agents. According to these results, PEGylated RIPs can be constructed with

  9. 基于人工神经网络模型的地下水水位动态变化模拟%Dynamic Variation Simulation of Ground Water Table Based on Artificial Neural Network Model

    Institute of Scientific and Technical Information of China (English)

    魏光辉

    2015-01-01

    Predication of the ground water table plays an important role in planning management of catchement surface and ground water resources.In this study, the artificial neural network model is applied in predication of the ground water table around the Xinier reser-voir.By application of data from 6 monitoring wells in the study area and of the artificial neural network model, the ground water table af-ter one week is predicated by simulation.The factors input the model include evaporation, reservoir level, escape canal level, water pumped volume and ground water table of the monitoring wells in last week.Therefore, the model is with 15 input points and 6 output points.Three different neural network methods of GDX, LM and BR methods are applied for the predication of the ground water table. The study shows that all three methods perform well in the predication.Generally, BR performance is better than these of GDX and LM. The artificial neural network model trained by BR method is applied for the predication of the ground water table in future 2nd, 3rd and 4th weeks in the study area.The simulation results are still better although the accuracy of the predication of the ground water table slight-ly decreases with time increment.%地下水水位的预测在流域地表水和地下水资源的综合规划管理中起着非常重要的作用。在该研究中,人工神经网络模型被应用于希尼尔水库周边地下水水位的预测中。采用研究区6口地下水观测井资料,用人工神经网络模型进行模拟预测1周后的地下水水位。模型输入因子包括此前1周蒸发量、水库水位、排渠水位、抽水量和观测井地下水位,因此模型有15个输入节点和6个输出节点。将3种不同的神经网络训练算法,即自适应学习速率动量梯度下降反向传播算法( GDX)、LM算法和贝叶斯正则化算法( BR)用于地下水水位预测,并对模拟结果进行了评估。结果表明:3种神经

  10. Assessment of Irrigation Land Suitability and Development of Map for the Fogera Catchment Using GIS, South Gondar

    Directory of Open Access Journals (Sweden)

    Dagnenet Sultan

    2013-01-01

    Full Text Available Irrigation land suitability assessment and mapping play an imperative role for sustainable utilization of scarce physical land resources. The objectives of this study were to prepare spatial data base of physical land resources for irrigated agriculture and to assess land suitability for irrigation and developing suitable area map for the study area. The study was conducted at Fogera catchment, South Gondar. Soil and water sampling spots were selected based on free and grid survey techniques and their locations were taken using Global Positioning System (GPS. Geographical Information System (GIS techniques were used to develop irrigation land suitability map of the study area. Attributes of parameters were collected and used for suitability assessment. Attributes used as criteria for irrigation suitability analysis were ECe, ESP, soil depth, texture, pH, top and sub soil stoniness, water table depth, flood hazard, ground water quality (SAR and EC and slope. Point data with their attribute were arranged and proximity analysis of Arc-GIS was made this resulted into twelve mapping units. The final irrigation suitability map of the project area was derived after overlay analysis. On the basis of stoniness, soil salinity, soil alkalinity, soil depth and groundwater quality it was concluded that 72 percent of the study area is potentially suitable for irrigation and 28 percent was classified as unsuitable (N due to drainage limitation, flood hazard, texture and slope factors. Of the potentially suitable land, 1 percent was highly suitable (S1, 28 percent was moderately suitable (S2, and 43 percent is marginally suitable (S3.

  11. Learning from concurrent Lightning Imaging Sensor and Lightning Mapping Array observations in preparation for the MTG-LI mission

    Science.gov (United States)

    Defer, Eric; Bovalo, Christophe; Coquillat, Sylvain; Pinty, Jean-Pierre; Farges, Thomas; Krehbiel, Paul; Rison, William

    2016-04-01

    The upcoming decade will see the deployment and the operation of French, European and American space-based missions dedicated to the detection and the characterization of the lightning activity on Earth. For instance the Tool for the Analysis of Radiation from lightNIng and Sprites (TARANIS) mission, with an expected launch in 2018, is a CNES mission dedicated to the study of impulsive energy transfers between the atmosphere of the Earth and the space environment. It will carry a package of Micro Cameras and Photometers (MCP) to detect and locate lightning flashes and triggered Transient Luminous Events (TLEs). At the European level, the Meteosat Third Generation Imager (MTG-I) satellites will carry in 2019 the Lightning Imager (LI) aimed at detecting and locating the lightning activity over almost the full disk of Earth as usually observed with Meteosat geostationary infrared/visible imagers. The American community plans to operate a similar instrument on the GOES-R mission for an effective operation in early 2016. In addition NASA will install in 2016 on the International Space Station the spare version of the Lightning Imaging Sensor (LIS) that has proved its capability to optically detect the tropical lightning activity from the Tropical Rainfall Measuring Mission (TRMM) spacecraft. We will present concurrent observations recorded by the optical space-borne Lightning Imaging Sensor (LIS) and the ground-based Very High Frequency (VHF) Lightning Mapping Array (LMA) for different types of lightning flashes. The properties of the cloud environment will also be considered in the analysis thanks to coincident observations of the different TRMM cloud sensors. The characteristics of the optical signal will be discussed according to the nature of the parent flash components and the cloud properties. This study should provide some insights not only on the expected optical signal that will be recorded by LI, but also on the definition of the validation strategy of LI, and

  12. Evaluation of a computer model to simulate water table response to subirrigation Avaliação de um modelo computacional para simular a resposta do lençol freático à subirrigação

    Directory of Open Access Journals (Sweden)

    Jadir Aparecido Rosa

    2002-12-01

    Full Text Available The objective of this work was to evaluate the water flow computer model, WATABLE, using experimental field observations on water table management plots from a site located near Hastings, FL, USA. The experimental field had scale drainage systems with provisions for subirrigation with buried microirrigation and conventional seepage irrigation systems. Potato (Solanum tuberosum L. growing seasons from years 1996 and 1997 were used to simulate the hydrology of the area. Water table levels, precipitation, irrigation and runoff volumes were continuously monitored. The model simulated the water movement from a buried microirrigation line source and the response of the water table to irrigation, precipitation, evapotranspiration, and deep percolation. The model was calibrated and verified by comparing simulated results with experimental field observations. The model performed very well in simulating seasonal runoff, irrigation volumes, and water table levels during crop growth. The two-dimensional model can be used to investigate different irrigation strategies involving water table management control. Applications of the model include optimization of the water table depth for each growth stage, and duration, frequency, and rate of irrigation.O objetivo deste trabalho foi avaliar o modelo computacional WATABLE usando-se dados de campo obtidos em uma área experimental em manejo de lençol freático, localizada em Hastings, FL, EUA. Na área experimental, estavam instalados um sistema de drenagem e sistemas de irrigação por subsuperfície com irrigação localizada e por canais. Ciclos de cultivo de batata (Solanum tuberosum L., nos anos de 1996 e 1997, foram usados para a simulação da hidrologia da área. Profundidades do lençol freático, chuvas, irrigação e escorrimento superficial foram monitorados constantemente. O modelo simulou o movimento da água a partir de uma linha de irrigação localizada enterrada, e a resposta do nível do len

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

    Science.gov (United States)

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

    2015-02-01

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

  14. Preparation of an antitumor and antivirus agent: chemical modification of α-MMC and MAP30 from Momordica Charantia L. with covalent conjugation of polyethyelene glycol

    Directory of Open Access Journals (Sweden)

    Meng Y

    2012-06-01

    Full Text Available Yao Meng,1,2 Shuangfeng Liu,1 Juan Li,3 Yanfa Meng,3 Xiaojun Zhao2,41School of Medical Laboratory Science, Chengdu Medical College, Chengdu, China; 2West China Hospital Laboratory of Nanomedicine and Institute for Nanobiomedical Technology and Membrane Biology, Sichuan University, Chengdu, China; 3Key Laboratory of Bio-resources and Eco-environment Ministry of Education/Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, China; 4Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USABackground: Alpha-momorcharin (α-MMC and momordica anti-HIV protein (MAP30 derived from Momordica charantia L. have been confirmed to possess antitumor and antivirus activities due to their RNA-N-glycosidase activity. However, strong immunogenicity and short plasma half-life limit their clinical application. To solve this problem, the two proteins were modified with (mPEG2-Lys-NHS (20 kDa.Methodology/principal findings: In this article, a novel purification strategy for the two main type I ribosome-inactivating proteins (RIPs, α-MMC and MAP30, was successfully developed for laboratory-scale preparation. Using this dramatic method, 200 mg of α-MMC and about 120 mg of MAP30 was obtained in only one purification process from 200 g of Momordica charantia seeds. The homogeneity and some other properties of the two proteins were assessed by gradient SDS-PAGE, electrospray ionization quadruple mass spectrometry, and N-terminal sequence analysis as well as Western blot. Two polyethylene glycol (PEGylated proteins were synthesized and purified. Homogeneous mono-, di-, or tri-PEGylated proteins were characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The analysis of antitumor and antivirus activities indicated that the serial PEGylated RIPs preserved moderate activities on JAR choriocarcinoma cells and herpes simplex

  15. Geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples, and its possible relationship with the prevalence of enamel fluorosis in children in four municipalities of the department of Huila (Colombia).

    Science.gov (United States)

    Martignon, Stefania; Opazo-Gutiérrez, Mario Omar; Velásquez-Riaño, Möritz; Orjuela-Osorio, Iván Rodrigo; Avila, Viviana; Martinez-Mier, Esperanza Angeles; González-Carrera, María Clara; Ruiz-Carrizosa, Jaime Alberto; Silva-Hermida, Blanca Cecilia

    2017-06-01

    Fluoride is an element that affects teeth and bone formation in animals and humans. Though the use of systemic fluoride is an evidence-based caries preventive measure, excessive ingestion can impair tooth development, mainly the mineralization of tooth enamel, leading to a condition known as enamel fluorosis. In this study, we investigated the geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples in four endemic enamel fluorosis sentinel municipalities of the department of Huila, Colombia (Pitalito, Altamira, El Agrado and Rivera), and its possible relationship with the prevalence of enamel fluorosis in children. The concentration of fluoride in drinking water, table salt, active sediment, rock, and soil was evaluated by means of an ion selective electrode and the geochemical analyses were performed using X-ray fluorescence. Geochemical analysis revealed fluoride concentrations under 15 mg/kg in active sediment, rock and soil samples, not indicative of a significant delivery to the watersheds studied. The concentration of fluoride in table salt was found to be under the inferior limit (less than 180 μg/g) established by the Colombian regulations. Likewise, exposure doses for fluoride water intake did not exceed the recommended total dose for all ages from 6 months. Although the evidence does not point out at rocks, soils, fluoride-bearing minerals, fluoridated salt and water, the hypothesis of these elements as responsible of the current prevalence of enamel fluorosis cannot be discarded since, aqueducts might have undergone significant changes overtime.

  16. Preparation of Cold Strain Maps

    Science.gov (United States)

    1957-08-01

    Trousers, field, wool, OD Trousers, field, cotton, OD Pootwear Boot, raukluk (with appropriate sodtgear) Headwear 19# Upper Body Clothing...cotton, OD Handwear Mittens, Arctic, trigger finger, w/inserts Footwear Boot, raukluk (with appropriate sock- gear) Headwear ’ Accenslon

  17. 氮沉降和水位下降对湿地生态系统的影响%The Effect of Nitrogen Deposition and Water Table Lowing-down on Wetland Ecosystem

    Institute of Scientific and Technical Information of China (English)

    李里; 刘伟

    2011-01-01

    The general situation of nitrogen deposition and water table Iowing-down were described, and the effects of nitrogen deposition and water table lowing-down on wetland ecosystem in the context of climate change were reviewed. Nitrogen deposition can increase plant productivity to a certain extent, specifically above ground biomass, net primary productivity and plant height. It also affects vegetation composition, facilitating the transition from lower plants such as moss to higher plant such as vascular plant. In addition, nitrogen deposition accelerates decomposition by microorganisms in two ways, removing constraining factors of microbial metabolism and changing the quality of substitutes being decomposed. Moreover, nitrogen deposition affects the flux of greenhouse gas (such as carbon dioxide,methane, nitrous oxide). Water table lowing-down reduces the rate of vegetation photosynthesis, leading to reduction of plant growth. It affects microbial community such as fungi and actinomycete community, promoting decomposition by microorganisms. It also impacts greenhouse gas emissions, increases the flux of carbon dioxide and nitrous oxide, and decreases the flux of methane.%介绍了湿地生态系统及其氮沉降和水位下降的概况,综述了全球变化背景下的氮沉降和水位下降对湿地生态系统的具体影响.氮沉降能够征一定范围内提高生产力,具体表现在植物的地上生物量、净初级生产力,植株高度等方面,氮沉降还影响植被组成,使苔藓类植物向维管植物过渡;氮沉降通过两种方式促进微生物分解,一是解除微生物代谢的限制因素,二是改变微生物分解底物的质量;此外,氮沉降还影响温室气体(甲烷、二氧化碳、氧化亚氮)的通量.水位下降后,植被的光合速率降低,生长降低,促进微生物的分解,使温室气体二氧化碳、氧化亚氮的通量增加,使甲烷通量降低.

  18. 时变补给条件下河渠间潜水的一维非稳定运动%Water Table Fluctuation Between Two Parallel Ditches Induced by Time-varying Recharge

    Institute of Scientific and Technical Information of China (English)

    夏强; 许模; 邓英尔; 李晓

    2015-01-01

    Taking account of exponentially and periodically time-varying recharge,water table fluctuation be-tween two parallel ditches was studied.The analytical solution was derived based on the first linearization method of Boussinesq equation,and Duhamel principle.This paper analyzed the characteristics of phreatic water move-ment by using three kinds of recharge rate functions including exponent-increase,exponent-decay,and sine func-tion.In the first case,water table rises monotonously with the increasing recharge rate;and watershed between the two ditches moves from the higher level side towards the other sides,but will never cross the middle line of the aquifer.In the exponent-decay case,water table goes up at the beginning,then falls after reaching a peak value;watershed firstly moves towards the middle of the aquifer,then turns back to the higher level side due to the decli-ning recharge rate.In the last case,water table periodically fluctuates corresponding to the sine function recharge;and there is a significant time lag between the stimulator and the respond;watershed sways back and forth between the higher level ditch and the middle of the aquifer.The results can be a clue to study the response of groundwater system to climate change,in addition to the transition rule between surface and ground water.%针对河渠间潜水的一维非稳定运动,考虑了补给强度的时变性,根据Boussinesq方程的第一线性化方法,应用Duhamel原理得到了方程的解析解,进一步得出补给强度为指数函数和三角函数的潜水位计算公式。通过算例分析补给强度指数增加、指数衰减和正弦函数变化条件下潜水面的变化特征,指数增加条件下潜水位单调增加,分水岭从高水位一侧向河间地块中部移动;指数衰减条件下潜水位先增大,后减小,具有一个峰值,分水岭先从高水位一侧向河间地块中部移动,之后随补给强度减弱返回到高水位河渠;

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

    Directory of Open Access Journals (Sweden)

    Rafael Mingoti

    2006-03-01

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

  20. Improved methods for chronic light-based motor mapping in mice: automated movement tracking with accelerometers, and chronic EEG recording in a bilateral thin-skull preparation.

    Directory of Open Access Journals (Sweden)

    Gergely eSilasi

    2013-07-01

    Full Text Available Optogenetic stimulation of the mouse cortex can be used to generate motor maps that are similar to maps derived from electrode-based stimulation. Here we present a refined set of procedures for repeated light-based motor mapping in ChR2-expressing mice implanted with a bilateral thinned-skull chronic window and a chronically implanted EEG electrode. Light stimulation is delivered sequentially to over 400 points across the cortex, and evoked movements are quantified on-line with a 3-axis accelerometer attached to each forelimb. Bilateral maps of forelimb movement amplitude and movement direction were generated at weekly intervals after recovery from cranial window implantation. We found that light pulses of ~2 mW produced well-defined maps that were centered approximately 0.7 mm anterior and 1.6 mm lateral from bregma. Map borders were defined by sites where light stimulation evoked EEG deflections, but not movements. Motor maps were similar in size and location between mice, and maps were stable over weeks in terms of the number of responsive sites, and the direction of evoked movements. We suggest that our method may be used to chronically assess evoked motor output in mice, and may be combined with other imaging tools to assess cortical reorganization or sensory-motor integration.

  1. Impact of water table depth and shallow groundwater use on salt leaching cycle in irrigated areas%灌区地下水控制埋深与利用量对洗盐周期的影响

    Institute of Scientific and Technical Information of China (English)

    李山; 罗纨; 贾忠华; 潘延鑫; 武迪

    2014-01-01

    灌区地下水位调控可增加作物对浅层地下水的利用量,但当地下水含盐量较高时,作物对其利用会加快盐分在根区的累积速度,进而影响灌溉淋洗制度。本文根据农田水盐平衡的基本原理,考虑不同埋深的浅层地下水利用条件下根区土壤盐分的累积过程,建立了土壤盐分淋洗周期的理论模型,并根据两组试验数据进行了应用分析。计算结果显示,位于半干旱区的研究区,地下水含盐量4.43 g/L,埋深维持在1 m和1.5 m时,多年平均降雨条件下,棉花生长期内需要排水洗盐的周期分别为100 d 和140 d;埋深大于2 m 时,淋洗周期超过了生长期。另一研究区位于干旱区,滴灌棉田地下水埋深为1.5 m时,用含盐量为2.81 g/L的微咸水进行滴灌,棉花生长期内需要排水淋洗的时间为78 d左右。因此,即使在灌区水位调控抬高地下水位后,在一个生长周期内,根区土壤盐分的增长过程仍然相对缓慢,为灌区制定淋洗制度提供了时间窗口。%Water table management in irrigated areas may increase shallow groundwater use by crops. But the high salt content of groundwater results in faster buildup of salinity in crop root zone,which in turn af-fects leaching schedule of the irrigation districts. Based on general salt and water balance in crop fields in irrigated areas, a simplified model was proposed in this paper to calculate leaching cycle for crops that use shallow groundwater at different water table depth, considering the salt accumulation process in root zone of crops. Subsequently, leaching cycles were calculated for two study sites with soil salinity measure-ments. For the case study in a semi-arid irrigation area,under the current irrigation scheduling and the av-erage rainfall condition, the calculated leaching cycle for cotton fields is 100 days for water table depth at 1 m and 140 days for water table depth at 1.5 m with the

  2. Preparation of mesoporous SiO2@azobenzene-COOH chemoselective nanoprobes for comprehensive mapping of amino metabolites in human serum.

    Science.gov (United States)

    Li, Hua; Qin, Qian; Qiao, Lizhen; Shi, Xianzhe; Xu, Guowang

    2015-06-30

    A novel type of mesoporous SiO2@H4/D4 tagged azobenzene-COOH chemoselective nanoprobe was developed for comprehensive mapping of amino metabolites in complex biological samples with high specificity and sensitivity.

  3. Benthic Habitat and Zone Maps of Puerto Rico 1999 - Prepared by Visual Interpretation from Remote Sensing Imagery Collected by NOAA, 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — There are 208 habitat and zone maps of Puerto Rico and is major islands. This project is a cooperative effort between the National Ocean Service, National Centers...

  4. Mapping a Pristine Glaciofluvial Aquifer on the Canadian Shield Using Ground-Penetrating Radar and Electrical Resistivity Tomography

    Science.gov (United States)

    Graves, L. W.; Shirokova, V.; Bank, C.

    2013-12-01

    Our study aims to construct a 3D structural model of an unconfined pristine aquifer in Laurentian Hills, Ontario, Canada. The stratigraphy of the study site, which covers about 5400 square meters, features reworked glaciofluvial sands and glacial till on top of Canadian Shield bedrock. A network of 25 existing piezometers provides ground-truth. We used two types of geophysical surveys to map the water table and the aquifer basin. Ground-penetrating radar (GPR) collected 40 profiles over distances up to 140 meters using 200MHz and 400MHz antennas with a survey wheel. The collected radargrams show a distinct reflective layer, which can be mapped to outcrops of glacial till within the area. This impermeable interface forms the aquitard. Depths of the subsurface features were calculated using hyperbolic fits on the radargrams in Matlab by determining wave velocity then converting measured two-way-time to depth. Electrical resistivity was used to determine the water table elevations because the unconfined water table did not reflect the radar waves. 20 resistivity profiles were collected in the same area using Wenner-Alpha and dipole-dipole arrays with both 24 and 48 electrodes and for 0.5, 0.75, 1.0 and 2.0 meter spacing. The inverted resistivity models show low resistivity values (resistivity values (2000-6000 Ohm.m) above 1 to 2 meter depths. These contrasting resistivity values correspond to saturated and wet sand (lower resistivity) to dry sand (higher resistivity); a correlation we could verify with several bore-hole logs. The water table is marked on the resistivity profiles as a steep resistivity gradient, and the depth can be added to the comprehensive 3D model. This model also incorporates hydrogeological characteristics and geochemical anomalies found within the aquifer. Ongoing seasonal and annual monitoring of the aquifer using geophysical methods will bring a fourth dimension to our understanding of this dynamic system. GPR Profile with Glacial Till

  5. Irrigation salinity hazard assessment and risk mapping in the lower Macintyre Valley, Australia.

    Science.gov (United States)

    Huang, Jingyi; Prochazka, Melissa J; Triantafilis, John

    2016-05-01

    In the Murray-Darling Basin of Australia, secondary soil salinization occurs due to excessive deep drainage and the presence of shallow saline water tables. In order to understand the cause and best management, soil and vadose zone information is necessary. This type of information has been generated in the Toobeah district but owing to the state border an inconsistent methodology was used. This has led to much confusion from stakeholders who are unable to understand the ambiguity of the results in terms of final overall risk of salinization. In this research, a digital soil mapping method that employs various ancillary data is presented. Firstly, an electromagnetic induction survey using a Geonics EM34 and EM38 was used to characterise soil and vadose zone stratigraphy. From the apparent electrical conductivity (ECa) collected, soil sampling locations were selected and with laboratory analysis carried out to determine average (2-12m) clay and EC of a saturated soil-paste extract (ECe). EM34 ECa, land surface parameters derived from a digital elevation model and measured soil data were used to establish multiple linear regression models, which allowed for mapping of various hazard factors, including clay and ECe. EM38 ECa data were calibrated to deep drainage obtained from Salt and Leaching Fraction (SaLF) modelling of soil data. Expert knowledge and indicator kriging were used to determine critical values where the salinity hazard factors were likely to contribute to a shallow saline water table (i.e., clay ≤35%; ECe>2.5dS/m, and deep drainage >100mm/year). This information was combined to produce an overall salinity risk map for the Toobeah district using indicator kriging. The risk map shows potential salinization areas and where detailed information is required and where targeted research can be conducted to monitor soil conditions and water table heights and determine best management strategies.

  6. 花管与潜水面相交下的冲击试验模型研究%STUDY OF MODEL OF SLUG TESTS PERFORMED IN WELLS WHEN WELLS SCREENED ACROSS WATER TABLE

    Institute of Scientific and Technical Information of China (English)

    高彬; 陈建生; 陈亮; 季纯波

    2013-01-01

    For the slug tests performed in wells screened across the water table in phreatic aquifer,the water injects into the wells through the upper and lower parts of the water table. By calculating the amount of the water flowed away from the lower part of the water table using the technique of tracer test with the concentration of solute,a new model of slug test in phreatic aquifer is built up;and the analytical solution of the new model is given. It′s different from the traditional ways to solve this problem,which usually do it by changing some coefficients to correct the radius of the wells. To demonstrate the correctness of this theory,a series of slug tests are conducfed in a fully penetrating well in the Jiangxiong Reservoir in Tibet. And then the hydraulic conductivity of the formation is calculated using the method. By comparing the result of this value to the calculating results of Bouwer-Rice slug,the results show that the proposed model can truly reflect the permeability characteristics of the formation. By analyzing the standard recovery curve of the slug test,it shows that curve can truly reflect the permeability characteristics of the aquifer when the curve decreases in a slower rate.%针对潜水井中的冲击试验,在花管与潜水面相交的情况下,由于注入井中的水分潜水面上、下两个部分流入含水层中,造成模型由线性变成非线性的问题,建立新的潜水井中的冲击试验计算模型,给出模型的解析解,并运用溶质浓度示踪技术,算出从潜水面以下部分流走的的水量,最终得到含水层渗透系数。而这与传统研究中,仅通过对测井的有效半径进行修正,来解决这一问题的方法不同。以西藏江雄水库库区一潜水完整井为例,进行现场试验,运用建立的模型,计算出含水层的渗透系数,并将其与Bouwer-Rice潜水井冲击试验模型的计算结果、以及抽水试验的结果进行对比,试验结果表

  7. Analyzing and Improving the Water-Table Fluctuation Method of Estimating Groundwater Recharge: Field Considerations Patros, T.B. and Parkin, G.W., School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada

    Science.gov (United States)

    Patros, T.; Parkin, G. W.

    2012-12-01

    The focus of the project is on measuring and quantifying groundwater recharge (GWR) using the water-table fluctuation (WTF) method. This method requires measuring the change in water-table (WT) height (Δh) during recharge (R) events and volumetric soil specific yield water content (θsy), (&/or) perhaps more correctly volumetric soil fillable water content (θf). The rise in WT can also result from other non-precipitation-related WTF causes (e.g., Lisse effect, temperature variations, barometric, lateral flow, Reverse Wieringermeer effect, encapsulated air, pumping), which must be counted for. The measurement of the storativity (S) terms (θsy) and/or θf) is, indeed, not clear-cut and often they are taken as being constant with depth, time, WT movement (Drying-Wetting & Freezing-Thawing) history and heterogeneity. In fact, these two terms (θsy & θf) are controversial in their definition, thus in their use, in the literature and may either overestimate the R, when using θsy, or underestimate it, when using θf. To resolve some of these questions, a novel-automated method is under development, at the University of Guelph's Elora Research Station (ERS) and Arboretum, along with a novel multi-event time series model. The long-term expected outcomes and significance of this study are; 1. Establishing accuracy in defining and evaluating the θsy and θf and using them accordingly in estimating GWR with the WTF method in order to overcome some of the existing substantial gaps in our knowledge of groundwater (GW) storage variation. 2. Obtaining GWR measurements at the local scale on a year-round basis, which are currently scarce or even completely lacking for many regions of Ontario and thus would provide a valuable database for guiding development of any policy requiring GWR. 3. Using this database to calibrate and test estimates of the spatial and temporal variability in regional-scale (watershed scale) GWR from approximate statistical techniques or deterministic

  8. Characterization of Anthropogenic Land Subsidence, its Relation to Fault System Geometry, and Their Consequences for Water Table Position in the El Paso, Texas Area Using InSAR and Gravity

    Science.gov (United States)

    Schiek, C. G.; Leuro, E.; Buckley, S.; Hurtado, J. M.

    2006-12-01

    The Hueco and Mesilla basins, located in the westernmost part of Texas and the southernmost part of New Mexico, are part of the Rio Grande Aquifer system. This aquifer system is the major water source for New Mexico, west Texas, and Mexico, including the cities of El Paso and Ciudad Juarez. The aquifer system lies within the Rio Grande Rift system, which spans the eastern edge of the Basin and Range province. Normal faults defining the Rio Grande Rift put structural and stratigraphic controls on aquifer systems such as those in the Mesilla and Hueco basins. These faults define stratigraphic controls on the aquifer by placing compacted rock next to unconsolidated and unsorted sediments, and act as conduits for water flow from the surface to the subsurface. We combine InSAR and gravity measurements to determine the location and geometry of subsurface faults within the basins. These faults can determine the shape and extent of observed land subsidence, which is a consequence of increased water pumping since the early 20th century. In addition, hydrologic information about the Rio Grande aquifer system, such as aquifer flow, compaction, and basin stratigraphy are compared with the InSAR results in order to determine how the subsidence is affecting the water table. Finally, subsidence patterns can indicate the presence and geometry of subsurface faults that may pose seismic hazards.

  9. Représentativité de l'échantillonnage géochimique et hydrodynamique en nappe libre du milieu semi-aride (Reliability of geochemical and hydrodynamic sample in a semi-arid water table)

    Science.gov (United States)

    Favreau, G.; Leduc, C.; Marlin, C.

    2000-11-01

    This paper evaluates the reliability of the geochemical and hydrodynamic sampling in a phreatic aquifer of semi-arid Africa. These remarks are based on a dense network and on detailed data collected for about ten years in the Continental Terminal water table near Niamey, Niger. The natural potentiometric fluctuations are seasonal (up to 6 m during the rainy season) and interannual (up to 10 m since the 1960s). Hydrodynamic measurements can be disturbed by artificial flooding into the wells (20% of the network) and by domestic drawings (up to 2 m of lowering). Geochemical characteristics can vary seasonally: isotopic modifications and salinity increase near recharge areas, with more stability further away. They can also vary artificially in wells because of their large opening towards the open air. Artifical increases of salinity of one order of magnitude and contaminations of 14C activities of up to 20 pmC occur in some wells by atmospheric dust inputs or organic matter which was has fallen into the well. In conclusion, some recommendations are given for a representative sampling in semi-arid phreatic aquifers.

  10. Monitoring of Landslide Areas with the Use of Contemporary Methods of Measuring and Mapping

    Science.gov (United States)

    Skrzypczak, Izabela; Kogut, Janusz; Kokoszka, Wanda; Zientek, Dawid

    2017-03-01

    In recent years, there is an increase of landslide risk observed, which is associated with intensive anthropogenic activities and extreme weather conditions. Appropriate monitoring and proper development of measurements resulting as maps of areas at risk of landslides enables us to estimate the risk in the social and economic aspect. Landslide monitoring in the framework of SOPO project is performed by several methods of measurements: monitoring of surface (GNSS measurement and laser scanning), monitoring in-deepth (inclinometer measurements) and monitoring of the hydrological changes and precipitation (measuring changes in water-table and rainfall).

  11. Monitoring of Landslide Areas with the Use of Contemporary Methods of Measuring and Mapping

    Directory of Open Access Journals (Sweden)

    Skrzypczak Izabela

    2017-03-01

    Full Text Available In recent years, there is an increase of landslide risk observed, which is associated with intensive anthropogenic activities and extreme weather conditions. Appropriate monitoring and proper development of measurements resulting as maps of areas at risk of landslides enables us to estimate the risk in the social and economic aspect. Landslide monitoring in the framework of SOPO project is performed by several methods of measurements: monitoring of surface (GNSS measurement and laser scanning, monitoring in-deepth (inclinometer measurements and monitoring of the hydrological changes and precipitation (measuring changes in water-table and rainfall.

  12. Pygmy squids and giant brains: mapping the complex cephalopod CNS by phalloidin staining of vibratome sections and whole-mount preparations

    DEFF Research Database (Denmark)

    Wollesen, T; Loesel, R; Wanninger, A

    2009-01-01

    Among bilaterian invertebrates, cephalopod molluscs (e.g., squids, cuttlefish and octopuses) have a central nervous system (CNS) that rivals in complexity that of the phylogenetically distant vertebrates (e.g., mouse and human). However, this prime example of convergent evolution has rarely been...... the subject of recent developmental and evolutionary studies, which may partly be due to the lack of suitable neural markers and the large size of cephalopod brains. Here, we demonstrate the usefulness of fluorescence-coupled phalloidin to characterize the CNS of cephalopods using histochemistry combined...... with confocal laser scanning microscopy. Whole-mount preparations of developmental stages as well as vibratome sections of embryonic and adult brains were analyzed and the benefits of this technique are illustrated. Compared to classical neuroanatomical and antibody-based studies, phalloidin labeling...

  13. The First Field Geologic Maps on Another Planet

    Science.gov (United States)

    Crumpler, L. S.

    2016-06-01

    Field geologic maps have been prepared from in situ ("field") observations during the traverse of Mars Exploration Rovers Spirit and Opportunity. These maps are the first tests of field geologic mapping methods at the human scale on another planet.

  14. GROUNDWATER QUALITY AND CONTAMINATION INDEX MAPPING IN CHANGCHUN CITY, CHINA

    Institute of Scientific and Technical Information of China (English)

    Hamadoun BOKAR; TANG Jie; LIN Nian-feng

    2004-01-01

    Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities.Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3- - Ca2+ and HCO3-of groundwater quality due to the increase of TDS, NO3- + NO2 (as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl- and NO3- ions and weak negative correlations between the depth of water table and Ca2+, 8O42-. C1- and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2 and Mn2+ ions.

  15. Pygmy squids and giant brains: mapping the complex cephalopod CNS by phalloidin staining of vibratome sections and whole-mount preparations.

    Science.gov (United States)

    Wollesen, T; Loesel, R; Wanninger, A

    2009-04-30

    Among bilaterian invertebrates, cephalopod molluscs (e.g., squids, cuttlefish and octopuses) have a central nervous system (CNS) that rivals in complexity that of the phylogenetically distant vertebrates (e.g., mouse and human). However, this prime example of convergent evolution has rarely been the subject of recent developmental and evolutionary studies, which may partly be due to the lack of suitable neural markers and the large size of cephalopod brains. Here, we demonstrate the usefulness of fluorescence-coupled phalloidin to characterize the CNS of cephalopods using histochemistry combined with confocal laser scanning microscopy. Whole-mount preparations of developmental stages as well as vibratome sections of embryonic and adult brains were analyzed and the benefits of this technique are illustrated. Compared to classical neuroanatomical and antibody-based studies, phalloidin labeling experiments are less time-consuming and allow a high throughput of samples. Besides other advantages summarized here, phalloidin reliably labels the entire neuropil of the CNS of all squids, cuttlefish and octopuses investigated. This facilitates high-resolution in toto reconstructions of the CNS and contributes to a better understanding of the organization of neural networks. Amenable for multi-labeling experiments employing antibodies against neurotransmitters, proteins and enzymes, phalloidin constitutes an excellent neuropil marker for the complex cephalopod CNS.

  16. Genetic Mapping

    Science.gov (United States)

    ... Fact Sheets Fact Sheets En Español: Mapeo Genético Genetic Mapping What is genetic mapping? How do researchers create ... genetic map? What are genetic markers? What is genetic mapping? Among the main goals of the Human Genome ...

  17. Calculation of Tsunami Damage and preparation of Inundation Maps by 2D and 3D numerical modeling in Göcek, Turkey

    Science.gov (United States)

    Ozer Sozdinler, C.; Arikawa, T.; Necmioglu, O.; Ozel, N. M.

    2016-12-01

    The Aegean and its surroundings form the most active part of the Africa-Eurasia collision zone responsible for the high level of seismicity in this region. It constitutes more than 60% of the expected seismicity in Europe up to Mw=8.2 (Moratto et al., 2007; Papazachos, 1990). Shaw and Jackson (2010) argued that the existing system of Hellenic Arc subduction-zone is capable of allowing very large but rare earthquakes on splay faults, such as the one occurred in 365, together with the contribution of small earthquakes. Based on an extensive earthquake generated tsunami scenario database, Necmioğlu and Özel (2015) showed that maximum wave heights in the Eastern Mediterranean for shallow earthquakes defined is >3 m in locations in, around and orthogonal to the Hellenic Arc. Considering the seismicity and the tsunami potential in Eastern Mediterranean, the investigation and monitoring of earthquake and tsunami hazard, and the preparation of mitigation strategies and national resilience plans would become inevitable in Turkey. Gocek town, as one of the Tsunami Forecast Points having a unique geography with many small bays and islands and a very popular touristic destination especially for yachtsmen, is selected in this study for the tsunami modeling by using high resolution bathymetric and topographic data with less than 4m grid size. The tsunami analyses are performed by the numerical codes NAMIDANCE (NAMIDANCE,2011) for 2D modeling and STOC-CADMAS (Arikawa,2014) for 3D modeling for the calculations of tsunami hydrodynamic parameters. Froude numbers, as one of the most important indicators for tsunami damage (Ozer, 2012) and the directions of current velocities inside marinas are solved by NAMIDANCE while STOC-CADMAS determines the tsunami pressure and force exerted onto the sea and land structures with 3D and non-hydrostatic approaches. The results are then used to determine the tsunami inundation and structural resilience and establish the tsunami preparedness and

  18. Impacto da lixiviação de nitrato e cloreto no lençol freático sob condições de cultivo irrigado Nitrogen and chloride impact on water table under irrigated condition

    Directory of Open Access Journals (Sweden)

    Eunice Maia de Andrade

    2009-02-01

    to groundwater. The aim of this research was to identify the irrigation management and the rainfall depth influence over nitrate and chloride concentration in the soil profiles, as well as the risk of water table pollution in the Irrigated District of Baixo Acaraú (DIBAU, Ceará, Brazil. Soil samples were taken each 50cm deep soil profiles until to saturated zone (7m in two different types of land use: irrigated area (S1 and native area (S2. Samples occurred during irrigation activities (Nov/06 and rainfall season (May/07. The water table was measured, monthly, from Dec/2003 to Nov/2005, Nov/2006, Mar and April/2007 in four shallow wells, two located in irrigated fields and the others in native. The greatest chloride concentration in the soil profiles was registered during rainfall season, suggesting the effect of sea-salt aerosols influence on chloride soil content. The greatest nitrate concentration occurred under irrigation period. Also, the results show that irrigation caused the groundwater concentration of NO3-N to increase from 1.52 to 19.3mgL-1, thereby, exceeding the standards on Regulation MS number 518/2004 and 357/2005 Resolution.

  19. Concept Maps

    OpenAIRE

    Schwendimann, Beat Adrian

    2014-01-01

    A concept map is a node-link diagram showing the semantic relationships among concepts. The technique for constructing concept maps is called "concept mapping". A concept map consists of nodes, arrows as linking lines, and linking phrases that describe the relationship between nodes. Two nodes connected with a labeled arrow are called a proposition. Concept maps are versatile graphic organizers that can represent many different forms of relationships between concepts. The relationship between...

  20. 应用GIS制作Coringa红树林物种分布图%Application of GIS in the Preparation of Species Distributional Maps for Coringa Mangroves Based on Ground Truth Data

    Institute of Scientific and Technical Information of China (English)

    B.Satyanarayana; A.V.Raman; 张秀英; 冯学智; F.Dehairs

    2004-01-01

    Coringa野生保护区是印度东海岸第二大红树林保护区.采用PCQM(Point Centered Quarter Meth-od)方法获取了该区红树林树木底面积数据Arcinfo 8.1制作物种密度分布图,结果显示,该区红树林植物有15种,分属8个科10个属,动物则包括7个门(Arthropda,Mollusca,Pisces,Amphibia,Reptiles,Aves andMammals).在15种红树林植物中,Avicennia marina,A.officinalis和Excoecaria agallocha是保护区中分布最广泛的种类,他们的分布密度随盐度的变化而变化,Rhizophora apiculata和R.mucronata则被限制在该区沿海边缘地带.%Coringa wildlife sanctuary is the second largest mangrove formation on the east coast of India with its rich floral and faunal biodiversity.The total number of floral species is composed of 15(8 families and 10 genera)conile fauna represented by 7 diverse groups such as Arthropoda,Mollusca,Pisces,Amphibia,Reptiles,Aves and Mammals.Out of 15 mangrove plant species,Avicennia marina ,A.o fficinalis and Excoecaria agallocha are the most widely distributed species within the sanctuary representing their wide tolerance capacity towards varying salinity ranges.Rhizophora apiculata and R.mucronata are mostly confined to the seaward fringes in this region.During present study,an attempt was made to prepare the species level distributional maps for the above said plant communities with the help of Arc Map 8.1 based on basal area(m2 per 0.1 hm2)estimations derived from PCQM(Point Cen-tered Quarter Method).

  1. 生鲜猪肉气调包装保鲜调理工艺优化%Optimization of Marinade Composition of Prepared Fresh Pork Packaged under Modified Atmosphere (MAP)

    Institute of Scientific and Technical Information of China (English)

    唐静; 张迎阳; 吴海舟; 黎良浩; 章建浩

    2014-01-01

    以鲜猪肉为原料,以料酒、复合香辛料、食盐的添加为试验因素,采用响应曲面试验优化冷鲜猪肉气调包装调理工艺。结果表明:在冷鲜猪肉的调理过程中,不同香辛料及食盐能有效的调理产品的理化品质,并能有效的抑制产品的微生物增长;料酒、复合香辛料、食盐的添加对调理猪肉气调包装后的菌落总数、色差等理化品质有显著作用(P<0.05);通过响应曲面优化法优化调理工艺中,盐分的添加分别与料酒和复合香辛料的添加对产品微生物总量有显著交互作用(P<0.05);优化得到调理猪肉最优工艺为料酒添加量6.70%、复合香辛料添加量1.20%、食盐添加量1.29%。在此条件下得到产品菌落总数为4.312 lg(CFU/g),可用于低温生鲜猪肉的调理生产。%A marinade composed mainly of cooking wine, complex spices and salt was developed for prepared fresh pork packaged under modified atmosphere (MAP). The three ingredients were optimized by response surface methodology. The results showed that both spices and salt were able to improve the physical and chemical qualities of products and effectively inhibit microbial growth. Each of these three ingredients had a significant effect on total bacterial count, color and other properties of MAP prepared pork (P<0.05). The response surface analysis indicated that the interactions of salts with cooking wine and with complex spices had a significant effect on the total number of colonies (P<0.05). The optimal marinade consisted of 6.70%cooking wine, 1.20%complex spices and 1.29%salt. The total number of colonies was 4.312 lg(CFU/g) using this marinade, suggesting its applicability for the production of low-temperature prepared pork.

  2. Map Projection

    CERN Document Server

    Ghaderpour, Ebrahim

    2014-01-01

    In this paper, we introduce some known map projections from a model of the Earth to a flat sheet of paper or map and derive the plotting equations for these projections. The first fundamental form and the Gaussian fundamental quantities are defined and applied to obtain the plotting equations and distortions in length, shape and size for some of these map projections.

  3. Text Maps: Helping Students Navigate Informational Texts.

    Science.gov (United States)

    Spencer, Brenda H.

    2003-01-01

    Notes that a text map is an instructional approach designed to help students gain fluency in reading content area materials. Discusses how the goal is to teach students about the important features of the material and how the maps can be used to build new understandings. Presents the procedures for preparing and using a text map. (SG)

  4. Topographic mapping

    Science.gov (United States)

    ,

    2008-01-01

    The U.S. Geological Survey (USGS) produced its first topographic map in 1879, the same year it was established. Today, more than 100 years and millions of map copies later, topographic mapping is still a central activity for the USGS. The topographic map remains an indispensable tool for government, science, industry, and leisure. Much has changed since early topographers traveled the unsettled West and carefully plotted the first USGS maps by hand. Advances in survey techniques, instrumentation, and design and printing technologies, as well as the use of aerial photography and satellite data, have dramatically improved mapping coverage, accuracy, and efficiency. Yet cartography, the art and science of mapping, may never before have undergone change more profound than today.

  5. Groundwater vulnerability to pollution mapping of Ranchi district using GIS.

    Science.gov (United States)

    Krishna, R; Iqbal, J; Gorai, A K; Pathak, G; Tuluri, F; Tchounwou, P B

    2015-12-01

    Groundwater pollution due to anthropogenic activities is one of the major environmental problems in urban and industrial areas. The present study demonstrates the integrated approach with GIS and DRASTIC model to derive a groundwater vulnerability to pollution map. The model considers the seven hydrogeological factors [Depth to water table (D), net recharge (R), aquifer media (A), soil media (S), topography or slope (T), impact of vadose zone (I) and hydraulic Conductivity(C)] for generating the groundwater vulnerability to pollution map. The model was applied for assessing the groundwater vulnerability to pollution in Ranchi district, Jharkhand, India. The model was validated by comparing the model output (vulnerability indices) with the observed nitrate concentrations in groundwater in the study area. The reason behind the selection of nitrate is that the major sources of nitrate in groundwater are anthropogenic in nature. Groundwater samples were collected from 30 wells/tube wells distributed in the study area. The samples were analyzed in the laboratory for measuring the nitrate concentrations in groundwater. A sensitivity analysis of the integrated model was performed to evaluate the influence of single parameters on groundwater vulnerability index. New weights were computed for each input parameters to understand the influence of individual hydrogeological factors in vulnerability indices in the study area. Aquifer vulnerability maps generated in this study can be used for environmental planning and groundwater management.

  6. Mapping Deeply

    OpenAIRE

    Denis Wood

    2015-01-01

    This is a description of an avant la lettre deep mapping project carried out by a geographer and a number of landscape architecture students in the early 1980s. Although humanists seem to take the “mapping” in deep mapping more metaphorically than cartographically, in this neighborhood mapping project, the mapmaking was taken literally, with the goal of producing an atlas of the neighborhood. In this, the neighborhood was construed as a transformer, turning the stuff of the world (gas, wate...

  7. Polynomial mappings

    CERN Document Server

    Narkiewicz, Wŀadysŀaw

    1995-01-01

    The book deals with certain algebraic and arithmetical questions concerning polynomial mappings in one or several variables. Algebraic properties of the ring Int(R) of polynomials mapping a given ring R into itself are presented in the first part, starting with classical results of Polya, Ostrowski and Skolem. The second part deals with fully invariant sets of polynomial mappings F in one or several variables, i.e. sets X satisfying F(X)=X . This includes in particular a study of cyclic points of such mappings in the case of rings of algebrai integers. The text contains several exercises and a list of open problems.

  8. Participatory Maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    2016-01-01

    practice. In particular, mapping environmental damage, endangered species, and human-made disasters has become one focal point for environmental knowledge production. This type of digital map has been highlighted as a processual turn in critical cartography, whereas in related computational journalism...... of a geo-visualization within information mapping that enhances embodiment in the experience of the information. InfoAmazonia is defined as a digitally created map-space within which journalistic practice can be seen as dynamic, performative interactions between journalists, ecosystems, space, and species...

  9. A coupled groundwater-flow-modelling and vulnerability-mapping methodology for karstic terrain management

    Science.gov (United States)

    Kavouri, Konstantina P.; Karatzas, George P.; Plagnes, Valérie

    2017-02-01

    A coupled groundwater-flow-modelling and vulnerability-mapping methodology for the management of karst aquifers with spatial variability is developed. The methodology takes into consideration the duality of flow and recharge in karst and introduces a simple method to integrate the effect of temporal storage in the unsaturated zone. In order to investigate the applicability of the developed methodology, simulation results are validated against available field measurement data. The criteria maps from the PaPRIKa vulnerability-mapping method are used to document the groundwater flow model. The FEFLOW model is employed for the simulation of the saturated zone of Palaikastro-Chochlakies karst aquifer, in the island of Crete, Greece, for the hydrological years 2010-2012. The simulated water table reproduces typical karst characteristics, such as steep slopes and preferred drain axes, and is in good agreement with field observations. Selected calculated error indicators—Nash-Sutcliffe efficiency (NSE), root mean squared error (RMSE) and model efficiency (E')—are within acceptable value ranges. Results indicate that different storage processes take place in different parts of the aquifer. The north-central part seems to be more sensitive to diffuse recharge, while the southern part is affected primarily by precipitation events. Sensitivity analysis is performed on the parameters of hydraulic conductivity and specific yield. The methodology is used to estimate the feasibility of artificial aquifer recharge (AAR) at the study area. Based on the developed methodology, guidelines were provided for the selection of the appropriate AAR scenario that has positive impact on the water table.

  10. A coupled groundwater-flow-modelling and vulnerability-mapping methodology for karstic terrain management

    Science.gov (United States)

    Kavouri, Konstantina P.; Karatzas, George P.; Plagnes, Valérie

    2017-08-01

    A coupled groundwater-flow-modelling and vulnerability-mapping methodology for the management of karst aquifers with spatial variability is developed. The methodology takes into consideration the duality of flow and recharge in karst and introduces a simple method to integrate the effect of temporal storage in the unsaturated zone. In order to investigate the applicability of the developed methodology, simulation results are validated against available field measurement data. The criteria maps from the PaPRIKa vulnerability-mapping method are used to document the groundwater flow model. The FEFLOW model is employed for the simulation of the saturated zone of Palaikastro-Chochlakies karst aquifer, in the island of Crete, Greece, for the hydrological years 2010-2012. The simulated water table reproduces typical karst characteristics, such as steep slopes and preferred drain axes, and is in good agreement with field observations. Selected calculated error indicators—Nash-Sutcliffe efficiency (NSE), root mean squared error (RMSE) and model efficiency (E')—are within acceptable value ranges. Results indicate that different storage processes take place in different parts of the aquifer. The north-central part seems to be more sensitive to diffuse recharge, while the southern part is affected primarily by precipitation events. Sensitivity analysis is performed on the parameters of hydraulic conductivity and specific yield. The methodology is used to estimate the feasibility of artificial aquifer recharge (AAR) at the study area. Based on the developed methodology, guidelines were provided for the selection of the appropriate AAR scenario that has positive impact on the water table.

  11. Geo-spatial approach for soil salinity mapping in Sego Irrigation Farm, South Ethiopia

    Directory of Open Access Journals (Sweden)

    Shegena Zewdu

    2017-01-01

    Full Text Available Soil salinization is a major problem affecting productivity of irrigated lands in arid and semi-arid areas. Managing salinity to minimize environmental impact is a prerequisite for sustainable irrigated agriculture. The objective of this study was to assess the level of salinity in Sego irrigated farm, Ethiopia and to map temporal and spatial distribution of salt affected soils to support management programmes. The study employed normal image classification, and developing models from ECe vs NDSI and thematic layers to map soil salinity, using geospatial tools. Multi-temporal Landsat TM images of 1984, 1995 and 2010 were used to detect salinity affected areas in the study area. Results of the study revealed that around 6 ha of the area gets moderately to strongly salinized per year. Empirical model developed from ECe vs NDSI of 2010 image using regression analysis revealed the coefficient of relation as 66%. The model was extended for the whole area, and revealed that 2.0% of the study area was strongly saline and 54.7% of the area was non-saline. Overlay model developed from water table, land form, land management type and land-cover has revealed that 11.2% of the study area was non-saline, whereas 47.2% and 3.0% was moderately and strongly saline, respectively. Validation of the models was made to test their predication capability and the overlay model has revealed better correlation coefficient of 67.3% to the measured ECe. Most of the salt affected areas were on shallow water table. Cambisols and fluvisols were greatly affected by salinity. The results indicate that long-term irrigation activities would affect agricultural potentiality of the area in the future, and geospatial tools are efficient and feasible for detecting salt affected areas from satellite images and thematic maps.

  12. One map policy (OMP) implementation strategy to accelerate mapping of regional spatial planing (RTRW) in Indonesia

    Science.gov (United States)

    Hasyim, Fuad; Subagio, Habib; Darmawan, Mulyanto

    2016-06-01

    A preparation of spatial planning documents require basic geospatial information and thematic accuracies. Recently these issues become important because spatial planning maps are impartial attachment of the regional act draft on spatial planning (PERDA). The needs of geospatial information in the preparation of spatial planning maps preparation can be divided into two major groups: (i). basic geospatial information (IGD), consist of of Indonesia Topographic maps (RBI), coastal and marine environmental maps (LPI), and geodetic control network and (ii). Thematic Geospatial Information (IGT). Currently, mostly local goverment in Indonesia have not finished their regulation draft on spatial planning due to some constrain including technical aspect. Some constrain in mapping of spatial planning are as follows: the availability of large scale ofbasic geospatial information, the availability of mapping guidelines, and human resources. Ideal conditions to be achieved for spatial planning maps are: (i) the availability of updated geospatial information in accordance with the scale needed for spatial planning maps, (ii) the guideline of mapping for spatial planning to support local government in completion their PERDA, and (iii) capacity building of local goverment human resources to completed spatial planning maps. The OMP strategies formulated to achieve these conditions are: (i) accelerating of IGD at scale of 1:50,000, 1: 25,000 and 1: 5,000, (ii) to accelerate mapping and integration of Thematic Geospatial Information (IGT) through stocktaking availability and mapping guidelines, (iii) the development of mapping guidelines and dissemination of spatial utilization and (iv) training of human resource on mapping technology.

  13. Planetary Geologic Mapping Handbook - 2009

    Science.gov (United States)

    Tanaka, K. L.; Skinner, J. A.; Hare, T. M.

    2009-01-01

    Geologic maps present, in an historical context, fundamental syntheses of interpretations of the materials, landforms, structures, and processes that characterize planetary surfaces and shallow subsurfaces (e.g., Varnes, 1974). Such maps also provide a contextual framework for summarizing and evaluating thematic research for a given region or body. In planetary exploration, for example, geologic maps are used for specialized investigations such as targeting regions of interest for data collection and for characterizing sites for landed missions. Whereas most modern terrestrial geologic maps are constructed from regional views provided by remote sensing data and supplemented in detail by field-based observations and measurements, planetary maps have been largely based on analyses of orbital photography. For planetary bodies in particular, geologic maps commonly represent a snapshot of a surface, because they are based on available information at a time when new data are still being acquired. Thus the field of planetary geologic mapping has been evolving rapidly to embrace the use of new data and modern technology and to accommodate the growing needs of planetary exploration. Planetary geologic maps have been published by the U.S. Geological Survey (USGS) since 1962 (Hackman, 1962). Over this time, numerous maps of several planetary bodies have been prepared at a variety of scales and projections using the best available image and topographic bases. Early geologic map bases commonly consisted of hand-mosaicked photographs or airbrushed shaded-relief views and geologic linework was manually drafted using mylar bases and ink drafting pens. Map publishing required a tedious process of scribing, color peel-coat preparation, typesetting, and photo-laboratory work. Beginning in the 1990s, inexpensive computing, display capability and user-friendly illustration software allowed maps to be drawn using digital tools rather than pen and ink, and mylar bases became obsolete

  14. Collection Mapping.

    Science.gov (United States)

    Harbour, Denise

    2002-01-01

    Explains collection mapping for library media collections. Discusses purposes for creating collection maps, including helping with selection and weeding decisions, showing how the collection supports the curriculum, and making budget decisions; and methods of data collection, including evaluating a collaboratively taught unit with the classroom…

  15. Causal mapping

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2006-01-01

    The lecture note explains how to use the causal mapping method as well as the theoretical framework aoosciated to the method......The lecture note explains how to use the causal mapping method as well as the theoretical framework aoosciated to the method...

  16. Affective Maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    of environmental knowledge production. It uses InfoAmazonia, the databased platform on Amazon rainforests, as an example of affective geo-visualization within information mapping that enhances embodiment in the experience of the information. Amazonia is defined as a digitally created affective (map)space within...

  17. Aquifer Vulnerability maps and climate change

    Science.gov (United States)

    Ducci, Daniela; Sellerino, Mariangela

    2017-04-01

    The aquifer vulnerability maps to contamination are used worldwide by environmental agencies and water-resource managers with the aim of preserving the water resources and of evaluating the most suitable areas where to locate new settlements. In the parametric methods, more used to assess the groundwater contamination vulnerability, e.g. the DRASTIC and the AVI methods, an important role is played by the protective capacity of cover layers to the introduction and transport of contaminants into the aquifer. Therefore, these methods point out the importance of the "Depth to water" parameter, which represents, where the aquifer is unconfined, the depth of the piezometric level and, where the aquifer is confined, the top of the aquifer. This parameter is rarely variable in confined aquifers and in deep unconfined aquifers, as karst aquifers, where the piezometric oscillations are low, compared with the depth of the water table. On the contrary, in shallow aquifers of flat areas, where in addition a large number of human activities are practiced and the contamination risk is high, the piezometric level varies suddenly with the rainfall, and it is very sensitive to drought periods and climatic changes. This affects noticeably the "Depth to water" parameter and consequently the vulnerability maps (e.g. 3 m of piezometric lowering can produce a change in the DRASTIC index from 10 to 7…). To validate this hypothesis, the DRASTC and AVI methods have been applied on a shallow aquifer located in a flat area in Campania (Italy,) considering data corresponding to an average rainfall period and to a drought period.

  18. Efeito do manejo do lençol freático na adaptação fisiomorfológica de duas espécies de trigo ao encharcamento Effect of the water table management in the morpho-physiological adaptation of two wheat species to waterlogging

    Directory of Open Access Journals (Sweden)

    Rinaldo de O. Calheiros

    2000-01-01

    Full Text Available Estudou-se o efeito de três manejos do lençol freático na indução de adaptações fisiomorfológicas dos trigos Triticum aestivum L. e Triticum durum L. à hipoxia, caracterizando e inferindo a influência relativa dos principais fatores físicos e biológicos interferentes. O experimento foi conduzido na ESALQ/USP, Piracicaba, SP, simulando-se ao máximo um meio físico/condição natural de uma várzea. Após a indução na fase vegetativa, através de períodos hipóxicos com duração progressiva, o grau de adaptação foi avaliado através de inundação permanente, incluindo o florescimento/formação de grãos. Observou-se: resposta diferenciada de exigência e/ou capacidade de extração de nutrientes entre as duas espécies; que a adubação foliar foi ineficiente para suprir as deficiências nutricionais da planta; que os manejos com curtos períodos de hipoxia induziram o trigo a adaptações fisiomorfológicas, porém não na intensidade ou eficiência de que resultassem parâmetros de produção em níveis adequados; enfim, que o manejo com o lençol freático mantido a 15 cm de profundidade durante todo o ciclo cultural foi o que propiciou melhor desempenho do trigo em cultivo sob encharcamento.The effect of three different water table managements in the morpho-physiological adaptation to waterlogging of Triticum aestivum, L. and Triticum durum, L., and the relative influence of the main physical and biological interferance factors were studied. The trial was conducted at ESALQ/USP, Piracicaba, SP, under simulated conditions of a natural low land. After introduction of stress adaptation during the vegetative growth stage, while applying progressive times of hipoxics periods, there were observed different requirements and/or extraction capacities of nutrients between the two species; the fertilization on leaves was not enough to avoid nutritional deficiencies in wheat under hipoxia. The water table management used resulted in

  19. CALS Mapping

    DEFF Research Database (Denmark)

    Collin, Ib; Nielsen, Povl Holm; Larsen, Michael Holm

    1998-01-01

    To enhance the industrial applications of CALS, CALS Center Danmark has developed a cost efficient and transparent assessment, CALS Mapping, to uncover the potential of CALS - primarily dedicated to small and medium sized enterprises. The idea behind CALS Mapping is that the CALS State...... enterprise is, when applied in a given organisation modified with respect to the industry regarded, hence irrelevant measure parameters are eliminated to avoid redundancy. This assessment of CALS Mapping, quantify the CALS potential of an organisation with the purpose of providing decision support to the top...

  20. Mapping VADEMECUM

    OpenAIRE

    1992-01-01

    The work plan for the implementation of the Convention on Long-Range Transboundary Air Pollution under the UN Economic Commission for Europe (UN ECE) includes the production of maps of critical loads, critical levels, and exceedances as a basis for developing potential abatement strategies for sulphur and nitrogen. This Vademecum is designed to provide guidance to those responsible for calculating and mapping critical loads, critical levels, and exceedances on a national or regional scale. Th...

  1. Comment on "Column-scale unsaturated hydraulic conductivity estimates in coarse-textured homogeneous and layered soils derived under steady-state evaporation from a water table" by M. Sadeghi, M. Tuller, M.R. Gohardoust and S.B. Jones

    Science.gov (United States)

    Lehmann, Peter; Assouline, Shmuel; Or, Dani

    2015-10-01

    The authors presented a new solution for steady-state evaporation during stage II from coarse-textured porous media (under isothermal conditions) that enables to (i) compute the maximum distance Dmax between the water table and the vaporization plane (where water phase change from liquid to vapor occurs) for a certain evaporation rate e and (ii) estimate the unsaturated hydraulic conductivity K(h) as a function of capillary head h by measuring e(Dmax). The mathematical procedure presented is correct and interesting, however, the study makes various unsubstantiated claims regarding potential generalization of the results that deserve some scrutiny considering the wealth of experimental and other physically-based theoretical studies of this important phenomenon. The general outcome is that we consider the conclusion as presented in the abstract ;The presented approach offers an alternative method for determination of unsaturated hydraulic conductivity of homogeneous coarse-textured soils and a new solution for prediction of the effective unsaturated hydraulic conductivity of layered coarse-textured soils; unfounded. In the comment below we address (i) the confusion between different definitions of hydraulic continuity of the liquid phase, (ii) the limited application of the method to a small range of evaporative fluxes, (iii) the plausibility of interpretations assuming hydraulic continuity across 10's of meters, (iv) the correctness of the estimations of maximum hydraulic continuity length Dmax from water table depth D for the coarse textured media considered in the study, and (v) a questionable application of the method for layered profiles. We first comment on some of the key derivations and their relations to soil properties and boundary conditions, and then discuss the physical validity of some of the generalization claims.

  2. Comparison of saturated areas mapping methods in the Jizera Mountains, Czech Republic

    Directory of Open Access Journals (Sweden)

    Kulasova Alena

    2014-06-01

    Full Text Available Understanding and modelling the processes of flood runoff generation is still a challenge in catchment hydrology. In particular, there are issues about how best to represent the effects of the antecedent state of saturation of a catchment on runoff formation and flood hydrographs. This paper reports on the experience of mapping saturated areas using measured water table by piezometers and more qualitative assessments of the state of the moisture at soil surface or immediately under it to provide information that can usefully condition model predictions. Vegetation patterns can also provide useful indicators of runoff source areas, but integrated over much longer periods of time. In this way, it might be more likely that models will get the right predictions for the right reasons.

  3. Regional sinkhole susceptibility maps: The Latium Region case (central Italy)

    Science.gov (United States)

    La Vigna, F.; Teoli, P.; Mazza, R.; Leoni, G.; Capelli, G.

    2012-04-01

    Several and frequent studies were internationally presented about landslide susceptibility, meanwhile in literature is missing a broad diffusion of studies regarding sinkhole susceptibility. That's why sinkhole recurrence depends on several geological conditions related to specific geological and hydrogeological context (sinkhole prone area) that vary case by case. Notwithstanding this regionalization problem of sinkhole recurrence, in the central Appenine sedimentary basins (Italy) a certain number of geological, geomorphologic and hydrogeological conditions (sinkhole predisposing issues) can be considered in common between the surveyed sinkholes. Eventually this could be compared with similar geological conditions and sinkhole occurrence in the rest of Italy or in other countries. In this case study is presented a probabilistic approach regarding the Latium Region deriving from the comparison between the regional sinkhole inventory realized during a precedent project and the dataset of the new Hydrogeological Map of Latium Region (scale 1:100.000). Indexed elements, chosen because associated to the majority of sinkhole phenomena, are: outcropping lithologies, water table depth, main faults (even if buried), hydrothermal springs, land use and the epicentres of recent earthquakes. These indexed elements were weighted and combined in a matrix which preliminary result is the sinkhole susceptibility map of Latium Region. When definitively validated, this approach could be suitable for local authorities to planning more targeted studies in major hazard areas.

  4. Tamarisk (Salt Cedar) Infestations in Northwestern Nevada Mapped Using Landsat TM Imagery and GIS Layers

    Science.gov (United States)

    Sengupta, D.; Geraci, C.; Kolkowitz, S.

    2004-12-01

    Tamarisk, also known as salt cedar (Tamarix sp.) is a prevalent invasive species that has infested many riparian areas in the southwestern United States. Mature salt cedar plants are resistant to high stress environments and fare well in drought conditions, mainly due to their extensive root systems that derive much of their sustenance from the water table rather than surface water and precipitation. The salt cedar root systems have altered hydrological patterns by tapping into underlying aquifers. This has decreased water available for recreational use, regional ecology and plant diversity. Many states have implemented salt cedar monitoring programs at the local level, but the problem of large-scale mapping of this invasive species has continued to be a challenge to land management agencies. Furthermore, inaccessible and unexplored areas continue to be absent in the mapping process. In August 2004, using field data consisting of large areas as training sets for classification of Landsat TM imagery, the DEVELOP student research team at NASA Ames Research Center generated a preliminary map of areas that that were susceptible to salt cedar growth for a region in northwestern Nevada. In addition to the remote sensing-based classification of satellite imagery, the team used the variables of elevation and estimated distance to the water table in conjunction with collected field data and knowledge of salt cedar growth habits to further refine the map. The team has further extended the mapping of key environmental factors of water availability for salt cedar, soil types and species distribution in regions infested by salt cedar. The investigation was carried out by 1) improving an existing GIS layer for water access using a suitable interpolation method, 2) including a GIS layer for soils associated with salt cedar growth and 3) completing field work to evaluate species distribution and regions of presence or absence of salt cedar. The outcome of this project served to

  5. The Chasm Green Machine: A Rapid Data Acquisition and Mapping System For Direct Observation of Shallow Hydrological Processes.

    Science.gov (United States)

    Quinn, P.; Merrett, S.

    CHASM (Catchment Hydrology and Sustainable Management) is a major UK funded project investigating all aspects of hydrological observation from point to basin scale. The project includes a mobile instrumentation component, which is now referred to as the 'Green Machine'. This research facility includes an All Terrain Vehicle, an on board high resolution GPS mapping and navigation system, an EM31, an EM38 and a Seistronix seismic kit. The goal of the project is to observe and map unsaturated and saturated zone hydrological processes within soils and drift through repeated map- ping campaigns. The hydrogeophysics kit will be validated against a dense series of ground based observations of soil moisture deficit, suction and peizometric logging instruments. The Green Machine also includes a portable drilling and coring kit that can reach 10m in depth. Thus, the EM31 will attempt to map macroscale fluxes in the water table position, the EM38 will attempt to map the soil moisture deficit, and the seismic profile will show the depth of soil and drift. This 'go anywhere', rapid mapping facility will attempt to map hydrological processes in 4 dimensions in a non- intrusive and extensive manner. Whilst this paper will reflect only the experimental design and some early results, it is hoped that the Green Machine will play an active role in the future of hydrogeophysical research.

  6. Cosmic Microwave Background Mapping

    Science.gov (United States)

    Verkhodanov, O. V.; Doroshkevich, A. G.

    2012-03-01

    The last decade of research in cosmology was connected with the ambitious experiments including space and ground base observations. Among the most impressive results of these investigations are the measurements of the cosmic microwave background (CMB) radiation like WMAP* and Planck. Exactly from the CMB studies, we have started the epoch of the precision cosmology when generally the values of cosmological parameters have been known and present research is devoted to improvement of the precision. These achievements are connected with both the creation of the new facilities in millimeter and submillimeter astronomy (e.g., satellites, receivers, antennas, computers) and development of the methods for the CMB data analysis. Actually, the process of data analysis contains several technical stages including 1. Registration of time-ordered data (TOD) 2. Pixelization of the CMB data - map preparation 3. Component separation 4. Map statistics analysis 5. Map - spherical harmonics transformation 6. C(l)-spectrum calculation and spectrum statistics analysis 7. Cosmological parameters estimation Starting from the cosmic background explorer (COBE) experiment using the so-called Quadrilateralized Sky Cube Projection (see [1-3]), the problem of the whole sky CMB pixelization has attracted great interest and many such schemes were developed. Let us note however that accurate pixelization of the CMB data on the sphere is very important but not the final step of analysis. Usually, the next step implies the determination of the coefficients of the spherical harmonic decomposition of the CMB signal for both anisotropy and polarization. This means that some of the pixelization schemes provide a very accurate map but are inconvenient for further decomposition. This also means that the choice of suitable pixelization schemes depends upon the general goals of the investigation. In this review, we consider several of the most popular sky map pixelization schemes and link them with the

  7. Mapping Deeply

    Directory of Open Access Journals (Sweden)

    Denis Wood

    2015-08-01

    Full Text Available This is a description of an avant la lettre deep mapping project carried out by a geographer and a number of landscape architecture students in the early 1980s. Although humanists seem to take the “mapping” in deep mapping more metaphorically than cartographically, in this neighborhood mapping project, the mapmaking was taken literally, with the goal of producing an atlas of the neighborhood. In this, the neighborhood was construed as a transformer, turning the stuff of the world (gas, water, electricity into the stuff of individual lives (sidewalk graffiti, wind chimes, barking dogs, and vice versa. Maps in the central transformer section of the atlas were to have charted this process in action, as in one showing the route of an individual newspaper into the neighborhood, then through the neighborhood to a home, and finally, as trash, out of the neighborhood in a garbage truck; though few of these had been completed when the project concluded in 1986. Resurrected in 1998 in an episode on Ira Glass’ This American Life, the atlas was finally published, as Everything Sings: Maps for a Narrative Atlas, in 2010 (and an expanded edition in 2013.

  8. Cognitive maps

    DEFF Research Database (Denmark)

    Minder, Bettina; Laursen, Linda Nhu; Lassen, Astrid Heidemann

    2014-01-01

    . Conceptual clustering is used to analyse and order information according to concepts or variables from within the data. The cognitive maps identified are validated through the comments of some of the same experts. The study presents three cognitive maps and respective world-views explaining how the design...... and innovation field are related and under which dimensions they differ. The paper draws preliminary conclusions on the implications of the different world- views on the innovation process. With the growing importance of the design approach in innovation e.g. design thinking, a clear conception...

  9. Cognitive maps

    DEFF Research Database (Denmark)

    Minder, Bettina; Laursen, Linda Nhu; Lassen, Astrid Heidemann

    2014-01-01

    . Conceptual clustering is used to analyse and order information according to concepts or variables from within the data. The cognitive maps identified are validated through the comments of some of the same experts. The study presents three cognitive maps and respective world-views explaining how the design...... and innovation field are related and under which dimensions they differ. The paper draws preliminary conclusions on the implications of the different world- views on the innovation process. With the growing importance of the design approach in innovation e.g. design thinking, a clear conception...

  10. Electrophoretic High Molecular Weight DNA Purification Enables Optical Mapping

    OpenAIRE

    Maydan, Jason; THOMAS, Matthew; Tabanfar, Leyla; Mai, Laura; Poon, Hau-Ling; Pe, Joel; HAHN, KRISTEN; Goji, Noriko; Amoako, Kingsley; Marziali, Andre; Hanson, Dan

    2013-01-01

    Optical mapping generates an ordered restriction map from single, long DNA molecules. By overlapping restriction maps from multiple molecules, a physical map of entire chromosomes and genomes is constructed, greatly facilitating genome assembly in next generation sequencing projects, comparative genomics and strain typing. However, optical mapping relies on a method of preparing high quality DNA >250 kb in length, which can be challenging from some organisms and sample types. Here we demonstr...

  11. Landslide susceptibility map: from research to application

    Science.gov (United States)

    Fiorucci, Federica; Reichenbach, Paola; Ardizzone, Francesca; Rossi, Mauro; Felicioni, Giulia; Antonini, Guendalina

    2014-05-01

    Susceptibility map is an important and essential tool in environmental planning, to evaluate landslide hazard and risk and for a correct and responsible management of the territory. Landslide susceptibility is the likelihood of a landslide occurring in an area on the basis of local terrain conditions. Can be expressed as the probability that any given region will be affected by landslides, i.e. an estimate of "where" landslides are likely to occur. In this work we present two examples of landslide susceptibility map prepared for the Umbria Region and for the Perugia Municipality. These two maps were realized following official request from the Regional and Municipal government to the Research Institute for the Hydrogeological Protection (CNR-IRPI). The susceptibility map prepared for the Umbria Region represents the development of previous agreements focused to prepare: i) a landslide inventory map that was included in the Urban Territorial Planning (PUT) and ii) a series of maps for the Regional Plan for Multi-risk Prevention. The activities carried out for the Umbria Region were focused to define and apply methods and techniques for landslide susceptibility zonation. Susceptibility maps were prepared exploiting a multivariate statistical model (linear discriminant analysis) for the five Civil Protection Alert Zones defined in the regional territory. The five resulting maps were tested and validated using the spatial distribution of recent landslide events that occurred in the region. The susceptibility map for the Perugia Municipality was prepared to be integrated as one of the cartographic product in the Municipal development plan (PRG - Piano Regolatore Generale) as required by the existing legislation. At strategic level, one of the main objectives of the PRG, is to establish a framework of knowledge and legal aspects for the management of geo-hydrological risk. At national level most of the susceptibility maps prepared for the PRG, were and still are obtained

  12. Projective mapping

    DEFF Research Database (Denmark)

    Dehlholm, Christian; Brockhoff, Per B.; Bredie, Wender Laurentius Petrus

    2012-01-01

    Projective Mapping (Risvik et.al., 1994) and its Napping (Pagès, 2003) variations have become increasingly popular in the sensory field for rapid collection of spontaneous product perceptions. It has been applied in variations which sometimes are caused by the purpose of the analysis and sometime...

  13. Mole Mapping.

    Science.gov (United States)

    Crippen, Kent J.; Curtright, Robert D.; Brooks, David W.

    2000-01-01

    The abstract nature of the mole and its applications to problem solving make learning the concept difficult for students, and teaching the concept challenging for teachers. Presents activities that use concept maps and graphing calculators as tools for solving mole problems. (ASK)

  14. Participatory maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    looks at computer-assisted cartography as part of environmental knowledge production. It uses InfoAmazonia, the databased platform on Amazon rainforests, as an example of affective geo-visualization within information mapping that enhances embodiment in the experience of the information. Amazonia...

  15. Caracterização da vegetação de restinga da RPPN de Maracaípe, PE, Brasil, com base na fisionomia, flora, nutrientes do solo e lençol freático Characterization of restinga vegetation at Maracaípe, Pernambuco State, Brazil, based on physiognomy, flora, soil nutrients, and water-table level

    Directory of Open Access Journals (Sweden)

    Eduardo Bezerra de Almeida Jr.

    2009-03-01

    Full Text Available O objetivo deste estudo foi realizar o levantamento florístico e descrever as fisionomias, relacionando-as com as formas de vida, fertilidade do solo e variações do lençol freático encontradas na restinga de Maracaípe. A área possui 76,2 ha de vegetação de restinga, sob as coordenadas 08º31'48"S e 35º01'05"W. Possui clima do tipo As' e solo classificado como Neossolo Quartzarênico. Foram feitas caminhadas aleatórias nas três fisionomias existentes - floresta, campo não inundável e campo inundável, durante o período de julho/2003 a julho/2005, para coleta de material botânico. A lista florística foi comparada a outras listas de restinga da região Nordeste. Foram inventariadas 187 espécies, 148 gêneros, distribuídas em 71 famílias. Entre as famílias mais representativas, destacam-se: Poaceae (13 espécies, Cyperaceae (12, Myrtaceae (10, Orchidaceae (9, Rubiaceae (8, Bromeliaceae e Fabaceae (7. A forma de vida "fanerófito" foi elevada na fisionomia florestal e as formas "caméfito", "terófito" e "criptófito", nas fisionomias campo inundável e não inundável. Os solos das fisionomias diferiram quanto à composição química e só ocorreu afloramento do lençol freático na fisionomia campo inundável. Este estudo permitiu concluir que a proporção de formas de vida, variação no nível do lençol freático, matéria orgânica e teor de alumínio no solo foram determinantes na separação das fisionomias da restinga de Maracaípe.We undertook a floristic survey to describe the phytophysiognomies of a restinga at Maracaípe, and related these to life form, soil fertility, and variation in the local water-table level. The study area is located at 08º31'48"S and 35º01'05"W, and has 76.2 ha of restinga vegetation. The regional climate is classified as As' and local soils are sandy Neosols. Random walks to collect botanical material were made in the three different vegetation physiognomies found in the area - forest

  16. Solution preparation

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.G.

    1982-01-01

    Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results.

  17. Geologic map of the Oasis Valley basin and vicinity, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Fridrich, C.J.; Minor, S.A.; Ryder, P.L.; Slate, J.L.

    2000-01-13

    This map and accompanying cross sections present an updated synthesis of the geologic framework of the Oasis Valley area, a major groundwater discharge site located about 15 km west of the Nevada Test Site. Most of the data presented in this compilation is new geologic map data, as discussed below. In addition, the cross sections incorporate new geophysical data that have become available in the last three years (Grauch and others, 1997; written comm., 1999; Hildenbrand and others, 1999; Mankinen and others, 1999). Geophysical data are used to estimate the thickness of the Tertiary volcanic and sedimentary rocks on the cross sections, and to identify major concealed structures. Large contiguous parts of the map area are covered either by alluvium or by volcanic units deposited after development of the major structures present at the depth of the water table and below. Hence, geophysical data provide critical constraints on our geologic interpretations. A companion paper by Fridrich and others (1999) and the above-cited reports by Hildenbrand and others (1999) and Mankinen and others (1999) provide explanations of the interpretations that are presented graphically on this map. This map covers nine 7.5-minute quadrangles in Nye County, Nevada, centered on the Thirsty Canyon SW quadrangle, and is a compilation of one published quadrangle map (O'Connor and others, 1966) and eight new quadrangle maps, two of which have been previously released (Minor and others, 1997; 1998). The cross sections that accompany this map were drawn to a depth of about 5 km below land surface at the request of hydrologists who are modeling the Death Valley groundwater system.

  18. The History Of Genome Mapping In Fragaria Spp.

    Directory of Open Access Journals (Sweden)

    Mohamed Abdel-Rahman Moustafa Abdel-Wahab

    2014-12-01

    Full Text Available This overview summarizes the research programs devoted to mapping the genomes within Fragaria genus. A few genetic linkage maps of diploid and octoploid Fragaria species as well as impressive physical map of F. vesca were developed in the last decade and resulted in the collection of data useful for further fundamental and applied studies. The information concerning the rules for proper preparation of mapping population, the choice of markers useful for generating linkage map, the saturation of existing maps with new markers linked to economically important traits, as well as problems faced during mapping process are presented in this paper.

  19. Some examples of tactical crime mapping in South Africa

    CSIR Research Space (South Africa)

    Cooper, Antony K

    2002-01-01

    Full Text Available , and the principle objective of this work was to prepare maps for use in court, to facilitate the understanding by the whole of the court of the proceedings of complex cases. In addition, the mapping process often enhanced the quality of the preparation of the case...

  20. Some examples of tactical crime mapping in South Africa.

    CSIR Research Space (South Africa)

    Cooper, Anthony K

    2002-01-01

    Full Text Available , and the principle objective of this work was to prepare maps for use in court, to facilitate the understanding by the whole of the court of the proceedings of complex cases. In addition, the mapping process often enhanced the quality of the preparation of the case...

  1. MAPPING INNOVATION

    DEFF Research Database (Denmark)

    Thuesen, Christian Langhoff; Koch, Christian

    2011-01-01

    By adopting a theoretical framework from strategic niche management research (SNM) this paper presents an analysis of the innovation system of the Danish Construction industry. The analysis shows a multifaceted landscape of innovation around an existing regime, built around existing ways of working...... and developed over generations. The regime is challenged from various niches and the socio-technical landscape through trends as globalization. Three niches (Lean Construction, BIM and System Deliveries) are subject to a detailed analysis showing partly incompatible rationales and various degrees of innovation...... potential. The paper further discusses how existing policymaking operates in a number of tensions one being between government and governance. Based on the concepts from SNM the paper introduces an innovation map in order to support the development of meta-governance policymaking. By mapping some...

  2. Mapping filmmaking

    DEFF Research Database (Denmark)

    Gilje, Øystein; Frølunde, Lisbeth; Lindstrand, Fredrik

    2010-01-01

    This chapter concerns mapping patterns in regards to how young filmmakers (age 15 – 20) in the Scandinavian countries learn about filmmaking. To uncover the patterns, we present portraits of four young filmmakers who participated in the Scandinavian research project Making a filmmaker. The focus ...... is on their learning practices and how they create ‘learning paths’ in relation to resources in diverse learning contexts, whether formal, non-formal and informal contexts.......This chapter concerns mapping patterns in regards to how young filmmakers (age 15 – 20) in the Scandinavian countries learn about filmmaking. To uncover the patterns, we present portraits of four young filmmakers who participated in the Scandinavian research project Making a filmmaker. The focus...

  3. Self-Mapping in Treating Suicide Ideation: A Case Study

    Science.gov (United States)

    Robertson, Lloyd Hawkeye

    2011-01-01

    This case study traces the development and use of a self-mapping exercise in the treatment of a youth who had been at risk for re-attempting suicide. A life skills exercise was modified to identify units of culture called "memes" from which a map of the youth's self was prepared. A successful treatment plan followed the mapping exercise. The…

  4. 44 CFR 64.3 - Flood Insurance Maps.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Insurance Maps. 64.3... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program COMMUNITIES ELIGIBLE FOR THE SALE OF INSURANCE § 64.3 Flood Insurance Maps. (a) The following maps may be prepared by...

  5. Concept Maps for Evaluating Learning of Sustainable Development

    Science.gov (United States)

    Shallcross, David C.

    2016-01-01

    Concept maps are used to assess student and cohort learning of sustainable development. The concept maps of 732 first-year engineering students were individually analyzed to detect patterns of learning and areas that were not well understood. Students were given 20 minutes each to prepare a concept map of at least 20 concepts using paper and pen.…

  6. Self-Mapping in Treating Suicide Ideation: A Case Study

    Science.gov (United States)

    Robertson, Lloyd Hawkeye

    2011-01-01

    This case study traces the development and use of a self-mapping exercise in the treatment of a youth who had been at risk for re-attempting suicide. A life skills exercise was modified to identify units of culture called "memes" from which a map of the youth's self was prepared. A successful treatment plan followed the mapping exercise. The…

  7. Concept Maps for Evaluating Learning of Sustainable Development

    Science.gov (United States)

    Shallcross, David C.

    2016-01-01

    Concept maps are used to assess student and cohort learning of sustainable development. The concept maps of 732 first-year engineering students were individually analyzed to detect patterns of learning and areas that were not well understood. Students were given 20 minutes each to prepare a concept map of at least 20 concepts using paper and pen.…

  8. Inception horizon concept as a basis for sinkhole hazard mapping

    Science.gov (United States)

    Vouillamoz, J.; Jeannin, P.-Y.; Kopp, L.; Chantry, R.

    2012-04-01

    The office for natural hazards of the Vaud canton (Switzerland) is interested for a pragmatic approach to map sinkhole hazard in karst areas. A team was created by merging resources from a geoengineering company (CSD) and a karst specialist (SISKA). Large areas in Vaud territory are limestone karst in which the collapse hazard is essentially related to the collapse of soft-rocks covering underground cavities, rather than the collapse of limestone roofs or underground chambers. This statement is probably not valid for cases in gypsum and salt. Thus, for limestone areas, zones of highest danger are voids covered by a thin layer of soft-sediments. The spatial distributions of void and cover-thickness should therefore be used for the hazard assessment. VOID ASSESSMENT Inception features (IF) are millimetre to decimetre thick planes (mainly bedding but also fractures) showing a mineralogical, a granulometrical or a physical contrast with the surrounding formation that make them especially susceptible to karst development (FILIPPONI ET AL., 2009). The analysis of more than 1500 km of cave passage showed that karst conduits are mainly developed along such discrete layers within a limestone series. The so-called Karst-ALEA method (FILIPPONI ET AL., 2011) is based on this concept and aims at assessing the probability of karst conduit occurrences in the drilling of a tunnel. This approach requires as entries the identification of inception features (IF), the recognition of paleo-water-table (PWT), and their respective spatial distribution in a 3D geological model. We suggest the Karst-ALEA method to be adjusted in order to assess the void distribution in subsurface as a basis for sinkhole hazard mapping. Inception features (horizons or fractures) and paleo-water-tables (PWT) have to be first identified using visible caves and dolines. These features should then be introduced into a 3D geological model. Intersections of HI and PWT located close to landsurface are areas with a

  9. Mapping of

    Directory of Open Access Journals (Sweden)

    Sayed M. Arafat

    2014-06-01

    Full Text Available Land cover map of North Sinai was produced based on the FAO-Land Cover Classification System (LCCS of 2004. The standard FAO classification scheme provides a standardized system of classification that can be used to analyze spatial and temporal land cover variability in the study area. This approach also has the advantage of facilitating the integration of Sinai land cover mapping products to be included with the regional and global land cover datasets. The total study area is covering a total area of 20,310.4 km2 (203,104 hectare. The landscape classification was based on SPOT4 data acquired in 2011 using combined multispectral bands of 20 m spatial resolution. Geographic Information System (GIS was used to manipulate the attributed layers of classification in order to reach the maximum possible accuracy. GIS was also used to include all necessary information. The identified vegetative land cover classes of the study area are irrigated herbaceous crops, irrigated tree crops and rain fed tree crops. The non-vegetated land covers in the study area include bare rock, bare soils (stony, very stony and salt crusts, loose and shifting sands and sand dunes. The water bodies were classified as artificial perennial water bodies (fish ponds and irrigated canals and natural perennial water bodies as lakes (standing. The artificial surfaces include linear and non-linear features.

  10. An Integrated Map of Soybean Physical Map and Genetic Map

    Institute of Scientific and Technical Information of China (English)

    QI Zhaoming; LI Hui; WU Qiong; SUN Yanan; LIU Chunyan; HU Guohua; CHEN Qingshan

    2009-01-01

    Soybean is a major crop in the world, and it is a main source of plant proteins and oil. A lot of soybean genetic maps and physical maps have been constructed, but there are no integrated map between soybean physical map and genetic map. In this study, soybean genome sequence data, released by JGI (US Department of Energy's Joint Genome Institute), had been downloaded. With the software Blast 2.2.16, a total of 161 super sequences were mapped on the soybean public genetic map to construct an integrated map. The length of these super sequences accounted for 73.08% of all the genome sequence. This integrated map could be used for gene cloning, gene mining, and comparative genome of legume.

  11. Difluoromethane preparation

    NARCIS (Netherlands)

    Wiersma, A.; Sandt, E.J.A.; Van Bekkum, H.; Makkee, M.; Moulijn, J.A.

    1996-01-01

    Abstract of NL 9401574 (A) The invention relates to a method for preparing difluoromethane, wherein dichlorodifluoromethane or monochlorodifluoromethane is brought into contact with hydrogen in the presence of palladium on activated carbon, wherein the loading of the palladium on the activated c

  12. Unit 02 - Maps and Map Analysis

    OpenAIRE

    Unit 55, CC in GIS; Rhind, David

    1990-01-01

    This unit explores the map analysis roots of GIS. It discusses cartography and its relationship to GIS, including topics such as map types and characteristics, the concept of scale, map projections, applications of maps, computer-assisted cartography and geographic data display and analysis.

  13. Mapping Resilience

    DEFF Research Database (Denmark)

    Carruth, Susan

    2015-01-01

    Resilience theory is a growing discipline with great relevance for the discipline of planning, particularly in fields like energy planning that face great uncertainty and rapidly transforming contexts. Building on the work of the Stockholm Resilience Centre, this paper begins by outlining...... the relationship between resilience and energy planning, suggesting that planning in, and with, time is a core necessity in this domain. It then reviews four examples of graphically mapping with time, highlighting some of the key challenges, before tentatively proposing a graphical language to be employed...... by planners when aiming to construct resilient energy plans. It concludes that a graphical language has the potential to be a significant tool, flexibly facilitating cross-disciplinary communication and decision-making, while emphasising that its role is to support imaginative, resilient planning rather than...

  14. Mapping Resilience

    DEFF Research Database (Denmark)

    Carruth, Susan

    2015-01-01

    Resilience theory is a growing discipline with great relevance for the discipline of planning, particularly in fields like energy planning that face great uncertainty and rapidly transforming contexts. Building on the work of the Stockholm Resilience Centre, this paper begins by outlining...... the relationship between resilience and energy planning, suggesting that planning in, and with, time is a core necessity in this domain. It then reviews four examples of graphically mapping with time, highlighting some of the key challenges, before tentatively proposing a graphical language to be employed...... by planners when aiming to construct resilient energy plans. It concludes that a graphical language has the potential to be a significant tool, flexibly facilitating cross-disciplinary communication and decision-making, while emphasising that its role is to support imaginative, resilient planning rather than...

  15. Geologic Map and Map Database of Eastern Sonoma and Western Napa Counties, California

    Science.gov (United States)

    Graymer, R.W.; Brabb, E.E.; Jones, D.L.; Barnes, J.; Nicholson, R.S.; Stamski, R.E.

    2007-01-01

    Introduction This report contains a new 1:100,000-scale geologic map, derived from a set of geologic map databases (Arc-Info coverages) containing information at 1:62,500-scale resolution, and a new description of the geologic map units and structural relations in the map area. Prepared as part of the San Francisco Bay Region Mapping Project, the study area includes the north-central part of the San Francisco Bay region, and forms the final piece of the effort to generate new, digital geologic maps and map databases for an area which includes Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Santa Cruz, Solano, and Sonoma Counties. Geologic mapping in Lake County in the north-central part of the map extent was not within the scope of the Project. The map and map database integrates both previously published reports and new geologic mapping and field checking by the authors (see Sources of Data index map on the map sheet or the Arc-Info coverage eswn-so and the textfile eswn-so.txt). This report contains new ideas about the geologic structures in the map area, including the active San Andreas Fault system, as well as the geologic units and their relations. Together, the map (or map database) and the unit descriptions in this report describe the composition, distribution, and orientation of geologic materials and structures within the study area at regional scale. Regional geologic information is important for analysis of earthquake shaking, liquifaction susceptibility, landslide susceptibility, engineering materials properties, mineral resources and hazards, as well as groundwater resources and hazards. These data also assist in answering questions about the geologic history and development of the California Coast Ranges.

  16. Planetary Geologic Mapping Handbook - 2010. Appendix

    Science.gov (United States)

    Tanaka, K. L.; Skinner, J. A., Jr.; Hare, T. M.

    2010-01-01

    Geologic maps present, in an historical context, fundamental syntheses of interpretations of the materials, landforms, structures, and processes that characterize planetary surfaces and shallow subsurfaces. Such maps also provide a contextual framework for summarizing and evaluating thematic research for a given region or body. In planetary exploration, for example, geologic maps are used for specialized investigations such as targeting regions of interest for data collection and for characterizing sites for landed missions. Whereas most modern terrestrial geologic maps are constructed from regional views provided by remote sensing data and supplemented in detail by field-based observations and measurements, planetary maps have been largely based on analyses of orbital photography. For planetary bodies in particular, geologic maps commonly represent a snapshot of a surface, because they are based on available information at a time when new data are still being acquired. Thus the field of planetary geologic mapping has been evolving rapidly to embrace the use of new data and modern technology and to accommodate the growing needs of planetary exploration. Planetary geologic maps have been published by the U.S. Geological Survey (USGS) since 1962. Over this time, numerous maps of several planetary bodies have been prepared at a variety of scales and projections using the best available image and topographic bases. Early geologic map bases commonly consisted of hand-mosaicked photographs or airbrushed shaded-relief views and geologic linework was manually drafted using mylar bases and ink drafting pens. Map publishing required a tedious process of scribing, color peel-coat preparation, typesetting, and photo-laboratory work. Beginning in the 1990s, inexpensive computing, display capability and user-friendly illustration software allowed maps to be drawn using digital tools rather than pen and ink, and mylar bases became obsolete. Terrestrial geologic maps published by

  17. California State Waters Map Series Data Catalog

    Science.gov (United States)

    Golden, Nadine E.

    2013-01-01

    In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California's State Waters. The CSMP approach is to create highly detailed seafloor maps and associated data layers through the collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. CSMP has divided coastal California into 110 map blocks (fig. 1), each to be published individually as USGS Scientific Investigations Maps (SIMs) at a scale of 1:24,000. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. This CSMP data catalog contains much of the data used to prepare the SIMs in the California State Waters Map Series. Other data that were used to prepare the maps were compiled from previously published sources (for example, onshore geology) and, thus, are not included herein.

  18. How Prepared is Prepared Enough?

    Science.gov (United States)

    Porter-Levy; Macleod; Rickert

    1996-10-01

    A 17-year-old female was in the final stage in treatment of right unilateral cleft lip and palate. She had undergone a number of previous surgeries. Hearing and speech were good on evaluation, and her social and family situation were deemed excellent. After preparatory orthodontics she underwent a Lefort I maxillary advancement. Surgery was successful and she was admitted into postoperative recovery. However, the lack of adequate preoperative preparation caused traumatic reaction from the patient and her parents: anxiety over appearance, crying, refusal of oral fluids and oral care, refusal of analgesia, and refusal to mobilize. The patience and persistence of hospital staff slowly overcame all adversities and the patient moved on to full and successful recovery, but this case prompted changes in preoperative procedures and involvement of patients and their families in postoperative meal selection, planing, and preparation.

  19. Stochastic description of water table fluctuations in wetlands

    National Research Council Canada - National Science Library

    Stefania Tamea; Rachata Muneepeerakul; Francesco Laio; Luca Ridolfi; Ignacio Rodriguez-Iturbe

    2010-01-01

    ... environment. Despite such importance, quantitative approaches to many aspects of wetlands are far from being adequate, above all the interaction between rainfall, vegetation, soil moisture and groundwater depth...

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

    African Journals Online (AJOL)

    2015-04-03

    Apr 3, 2015 ... addition, the time requirements for this method make it unsuit- able for agricultural .... auger smeared the surface of the auger-hole during the drilling process. ... which water level readings were taken every 10 s, using a Laser.

  1. OpenStreetMap over WMS

    Directory of Open Access Journals (Sweden)

    Přemysl Vohnout

    2010-02-01

    Full Text Available This paper discuss the issues which we faced, while preparing WMS server with OpenStreetMap data of whole Europe. This article is divided into three sections. First is about mandatory applications which are required for working WMS service with OpenStreetMap data. Second is focused on tuning up PostgreSQL. Third is focused on rendering time improvement of layers.

  2. Similaridade da composição hidroquímica das águas freáticas do perímetro irrigado do Baixo Acaraú, Ceará, Brasil. = The hydrochemical similarity of water table at Baixo Acaraú irrigated district, Ceará, Brazil.

    Directory of Open Access Journals (Sweden)

    Eunice Maia de Andrade

    2010-06-01

    Full Text Available Devido ao constante risco de contaminação das águas freáticas pela lixiviação de sais e substâncias tóxicas como resíduos de fertilizantes e pesticidas, torna-se necessário o conhecimento da dinâmica na qualidade das águas, e assim elaborar um planejamento de uso sustentável desse recurso. Tendo-se por base esta premissa elaborou-se uma investigação das águas freáticas do Perímetro Irrigado do Baixo Acaraú (DIBAU com o objetivo de classificar a qualidade das águas quanto à sua composição hidroquímica bem como identificar os elementos determinantes da qualidade das mesmas. As coletas de água foram realizadas mensalmente por um período de 27 meses (dez/2003 a nov/2005; nov/2006 e março e abr/2007 em 10 poços rasos distribuídos aleatoriamente sobre o DIBAU. Neste estudo foram considerados os cátions (Ca2+, Mg2+, Na+e K+ e os ânions (Cl-, HCO3-e SO4-2. A composição hidroquímica foi definida pelo do Diagrama de Piper, e a similaridade da qualidade das águas foi efetuada pela análise multivariada (análise de agrupamento. As águas dos poços investigados se agruparam sem apresentar continuidade geográfica,sendo o sódio e o cloreto os elementos determinantes dos quatro grupos formados. A similaridade das águas dos poços que formaramo Grupo 4, permitem uma redução no número de poços amostrados, o que minimiza os custos de monitoramento. Embora tenha ocorrido a formação de quatro grupos, pelo Diagrama de Piper, todas as águas foram classificadas como cloretadas sódicas. A análise de agrupamento identificou os elementos determinantes de cada grupo, enquanto o Diagrama de Piper classificou as águas semidentificar a maior ou menor contribuição de um determinado elemento. = It is constant the risk of contamination in the water table by leachining of salts and toxic waste, such as fertilizer andpesticides. Therefore, it is necessary to understand the dynamics of the quality of waters and devise a plan of

  3. Effects of Partial Rootzone Drying on Sap Flow and Water Balance of Pear Trees Under a Shallow Ground Water Table Condition%地下水位较高条件下不同根区湿润方式对 梨树根与茎液流及其水分平衡的影响

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The experiments were conducted to test sap flow and water balance of pear trees response to partial rootzone drying under a shallow water table condition. Three treatments, i.e. conventional flood irrigation (CFI), fixed 1/2 partial rootzone drying and the other 1/2 part irrigated (PRD), and alternate 1/2 partial rootzone drying and irrigating (ARDI), were designed. The EnviroSCAN probes and heat pulse sensors were used to monitor soil water dynamics and sap flow respectively. The results shown that the root sap flow of wet side was much larger than that of dry side in PRD and ARDI, also larger than that of the same side in CFI. The root sap flow of dry side in ARDI was restored and improved more quickly than in PRD after rewetting. The trunk sap flow in PRD was smaller than in CFI when one side was drying, and it was larger than in CFI after the dry side rewetting. The trunk sap flow in ARDI was smaller than in CFI, but larger than in PRD during one side drying. The daily water consumption in ARDI and PRD was smaller than that in CFI during the period of only one side irrigated. The compensatory effect for water uptake existed in the roots of wet side for ARDI and PRD, and the ability of root water uptake was enhanced when the dry side rewetting, and it related the duration of root drying. Daily root sap flow was significantly related to reference evapotranspiration, but these relations were markedly different for different surface wetting patterns and different sides. The daily trunk sap flow was also related to reference evapotranspiration, and the ratio of trunk sap flow and reference evapotranspiration was not same for the same soil water content under different surface wetting patterns. Irrigation water use was approximately reduced 1/2 in ARDI and in the drying periods of PRD compared with CFI, but water consumption of trees and trunk sap flow were not reduced the same percentage. The effects of partial rootzone drying on water balance and sap flow were

  4. GIS Based Spatial Data Analysis for Landslide Susceptibility Mapping

    Institute of Scientific and Technical Information of China (English)

    S.Sarkar; D.P.Kanungo; A.K.Patra; Pushpendra Kumar

    2008-01-01

    Landslide susceptibility map delineates the potential zones for landslides occurrence.The paper presents a statistical approach through spatial data analysis in GIS for landslide susceptibility mapping in parts of Sikkim Himalaya.Six important causative factors for landslide occurrences were selected and corresponding thematic data layers were prepared in GIS.Topographic maps,satellite image,field data and published maps constitute the input data for thematic layer preparation.Numerical weights for different categories of these factors were determined based on a statistical approach and the weighted thematic layers were integrated in GIS environment to generate the landslide susceptibility map of the area.The landslide susceptibility map classifies the area into five different landslide susceptible zones i.e.,very high,high,moderate,low and very low.This map was validated using the existing landslide distribution in the area.

  5. Direct targeted glycation of the free sulfhydryl group of cysteine residue (Cys-34) of BSA. Mapping of the glycation sites of the anti-tumor Thomsen-Friedenreich neoglycoconjugate vaccine prepared by Michael addition reaction.

    Science.gov (United States)

    Demian, Wael L L; Kottari, Naresh; Shiao, Tze Chieh; Randell, Edward; Roy, René; Banoub, Joseph H

    2014-12-01

    We present in this manuscript the characterization of the exact glycation sites of the Thomsen-Friedenreich antigen-BSA vaccine (TF antigen:BSA) prepared using a Michael addition reaction between the saccharide antigen as an electrophilic acceptor and the nucleophilic thiol and L-Lysine ε-amino groups of BSA using different ligation conditions. Matrix laser desorption ionization time-of-flight mass spectrometry of the neoglycoconjugates prepared with TF antigen:protein ratios of 2:1 and 8:1, allowed to observe, respectively, the protonated molecules for each neoglycoconjugates: [M + H](+) at m/z 67,599 and 70,905. The measurements of these molecular weights allowed us to confirm exactly the carbohydrate:protein ratios of these two synthetic vaccines. These were found to be closely formed by a TF antigen:BSA ratios of 2:1 and 8:1, respectively. Trypsin digestion and liquid chromatography coupled with electrospray ionization mass spectrometry allowed us to identify the series of released glycopeptide and peptide fragments. De novo sequencing affected by low-energy collision dissociation tandem mass spectrometry was then employed to unravel the precise glycation sites of these neoglycoconjugate vaccines. Finally, we identified, respectively, three diagnostic and characteristic glycated peptides for the synthetic glycoconjugate possessing a TF antigen:BSA ratio 2:1, whereas we have identified for the synthetic glycoconjugate having a TF:BSA ratio 8:1 a series of 14 glycated peptides. The net increase in the occupancy sites of these neoglycoconjugates was caused by the large number of glycoforms produced during the chemical ligation of the synthetic carbohydrate antigen onto the protein carrier. Copyright © 2014 John Wiley & Sons, Ltd.

  6. Landslide Hazard Zonation Mapping and Comparative Analysis of Hazard Zonation Maps

    Institute of Scientific and Technical Information of China (English)

    S. Sarkar; R. Anbalagan

    2008-01-01

    Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the landslide hazards. The main objective of the present work was to carry out macro landslide hazard zonation mapping on 1:50,000 scale in an area where regional level zonation mapping was conducted earlier. In the previous work the regional landslide hazard zonation maps of Srinagar-Rudraprayag area of Garhwal Himalaya in the state of Uttarakhand were prepared using subjective and objective approaches. In the present work the landslide hazard zonation mapping at macro level was carded out in a small area using a Landslide Hazard Evaluation Factor rating scheme. The hazard zonation map produced by using this technique classifies the area into relative hazard classes in which the high hazard zones well correspond with high frequency of landslides. The results of this map when compared with the regional zonation maps prepared earlier show that application of the present technique identified more details of the hazard zones, which are broadly shown in the earlier zonation maps.

  7. ShakeMap

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground...

  8. Mapping: A Course.

    Science.gov (United States)

    Whitmore, Paul M.

    1988-01-01

    Reviews the history of cartography. Describes the contributions of Strabo and Ptolemy in early maps. Identifies the work of Gerhard Mercator as the most important advancement in mapping. Discusses present mapping standards from history. (CW)

  9. Lunar Map Catalog

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Map Catalog includes various maps of the moon's surface, including Apollo landing sites; earthside, farside, and polar charts; photography index maps; zone...

  10. Investigation of remote sensing to detect near-surface groundwater on irrigated lands

    Science.gov (United States)

    Ryland, D. W.; Schmer, F. A.; Moore, D. G.

    1975-01-01

    The application of remote sensing techniques was studied for detecting areas with high water tables in irrigated agricultural lands. Aerial data were collected by the LANDSAT-1 satellite and aircraft over the Kansas/Bostwick Irrigation District in Republic and Jewell Counties, Kansas. LANDSAT-1 data for May 12 and August 10, 1973, and aircraft flights (midday and predawn) on August 10 and 11, 1973, and June 25 and 26, 1974, were obtained. Surface and water table contour maps and active observation well hydrographs were obtained from the Bureau of Reclamation for use in the analysis. Results of the study reveal that LANDSAT-1 data (May MSS band 6 and August MSS band 7) correlate significantly (0.01 level) with water table depth for 144 active observation wells located throughout the Kansas/Bostwick Irrigation District. However, a map of water table depths of less than 1.83 meters prepared from the LANDSAT-1 data did not compare favorably with a map of seeped lands of less than 1.22 m (4 feet) to the water table. Field evaluation of the map is necessary for a complete analysis. Analysis of three fields on a within or single-field basis for the 1973 LANDSAT-1 data also showed significant correlation results.

  11. Mapping with the Masses: Google Map Maker

    Science.gov (United States)

    Pfund, J.

    2008-12-01

    After some 15,000 years of map making, which saw the innovations of cardinal directions, map projections for a spherical earth, and GIS analysis, many parts of the world still appear as the "Dark Continent" on modern maps. Google Map Maker intends to shine a light on these areas by tapping into the power of the GeoWeb. Google Map Maker is a website which allows you to collaborate with others on one unified map to add, edit, locate, describe, and moderate map features, such as roads, cities, businesses, parks, schools and more, for certain regions of the world using Google Maps imagery. In this session, we will show some examples of how people are mapping with this powerful tool as well as what they are doing with the data. With Google Map Maker, you can become a citizen cartographer and join the global network of users helping to improve the quality of maps and local information in your region of interest. You are invited to map the world with us!

  12. Mapping Hurricane Rita inland storm tide

    Science.gov (United States)

    Berenbrock, Charles; Mason, Jr., Robert R.; Blanchard, Stephen F.; Simonovic, Slobodan P.

    2009-01-01

    Flood-inundation data are most useful for decision makers when presented in the context of maps of effected communities and (or) areas. But because the data are scarce and rarely cover the full extent of the flooding, interpolation and extrapolation of the information are needed. Many geographic information systems (GIS) provide various interpolation tools, but these tools often ignore the effects of the topographic and hydraulic features that influence flooding. A barrier mapping method was developed to improve maps of storm tide produced by Hurricane Rita. Maps were developed for the maximum storm tide and at 3-hour intervals from midnight (0000 hour) through noon (1200 hour) on September 24, 2005. The improved maps depict storm-tide elevations and the extent of flooding. The extent of storm-tide inundation from the improved maximum storm-tide map was compared to the extent of flood-inundation from a map prepared by the Federal Emergency Management Agency (FEMA). The boundaries from these two maps generally compared quite well especially along the Calcasieu River. Also a cross-section profile that parallels the Louisiana coast was developed from the maximum storm-tide map and included FEMA high-water marks.

  13. Effectiveness of basin morphometry, remote sensing, and applied geosciences on groundwater recharge potential mapping: a comparative study within a small watershed

    Science.gov (United States)

    Roy, Suvendu; Sahu, Abhay Sankar

    2016-06-01

    A multidisciplinary approach using the integrated field of geosciences (e.g., geomorphology, geotectonics, geophysics, and hydrology) is established to conduct groundwater recharge potential mapping of the Kunur River Basin, India. The relative mean error (RME) calculation of the results of three applied techniques and water table data from twenty-four observation wells in the basin over the 2000-2010 period are presented. Nine subbasins were identified and ranked for the RME calculation, where the observation wells-based ranking was taken as standard order for comparison. A linear model has been developed using six factors (drainage density, surface slope, ruggedness index, lineament density, Bouguer gravity anomaly, and potential maximum water retention capacity) and a grid-wise weighted index. In a separate comparative approach, the sub-basin and grid-wise analyses have been conducted to identify the suitable spatial unit for watershed level hydrological modeling.

  14. Mapping flood prone areas in southern Brazil: a combination of frequency analysis, HAND algorithm and remote sensing methods

    Science.gov (United States)

    Fabris Goerl, Roberto; Borges Chaffe, Pedro Luiz; Marcel Pellerin, Joel Robert; Altamirano Flores, Juan Antonio; Josina Abreu, Janete; Speckhann, Gustavo Andrei; Mattos Sanchez, Gerly

    2015-04-01

    Floods disaster damages several people around the world. There is a worldwide increasing trend of natural disasters frequency and their negative impacts related to the population growth and high urbanization in natural hazards zones. In Santa Catarina state, such as almost all southern Brazilian territory, floods are a frequent hydrological disaster. In this context, flood prone areas map is a important tool to avoid the construction of new settlements in non-urbanizations areas. The present work aimed to map flood prone areas in Palhoça City, Southern Brazil combining high resolution digital elevations data, remote sensing information, frequency analysis and High Above Nearest Drainage (HAND) algorithm. We used 17 years of daily discharge and stage data to calculate flood probability and return period. Remote Sensing (RS) with CBERS HRC image with 2,7m resolution was used. This image was taken one day after one flood occurrence and a band difference was used to extract the flood extent. HAND using DEM to calculate the altimetric difference between channel pixel and adjacent terrain values. All morphometric attributes used in HAND were extracted directly from the high resolution DEM (1m). Through CBERS image areas where flood level was higher than 0.5m were mapped. There is some kind of uncertain in establish HAND classes, since only distance to the channel was take in account. Thus, using other hydrological or spatial information can reduce this uncertain. To elaborate the final flood prone map, all this methods were combined. This map was classified in three main classes based on return period. It was notices that there is a strong spatial correlation between high susceptibility flood areas and geomorphological features like floodplains and Holocene beach ridges, places where water table emerges frequently. The final map was classified using three different colors (red, yellow and green) related to high, medium an law susceptibility flood areas. This mapping

  15. USGS National Seismic Hazard Maps

    Science.gov (United States)

    Frankel, A.D.; Mueller, C.S.; Barnhard, T.P.; Leyendecker, E.V.; Wesson, R.L.; Harmsen, S.C.; Klein, F.W.; Perkins, D.M.; Dickman, N.C.; Hanson, S.L.; Hopper, M.G.

    2000-01-01

    The U.S. Geological Survey (USGS) recently completed new probabilistic seismic hazard maps for the United States, including Alaska and Hawaii. These hazard maps form the basis of the probabilistic component of the design maps used in the 1997 edition of the NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, prepared by the Building Seismic Safety Council arid published by FEMA. The hazard maps depict peak horizontal ground acceleration and spectral response at 0.2, 0.3, and 1.0 sec periods, with 10%, 5%, and 2% probabilities of exceedance in 50 years, corresponding to return times of about 500, 1000, and 2500 years, respectively. In this paper we outline the methodology used to construct the hazard maps. There are three basic components to the maps. First, we use spatially smoothed historic seismicity as one portion of the hazard calculation. In this model, we apply the general observation that moderate and large earthquakes tend to occur near areas of previous small or moderate events, with some notable exceptions. Second, we consider large background source zones based on broad geologic criteria to quantify hazard in areas with little or no historic seismicity, but with the potential for generating large events. Third, we include the hazard from specific fault sources. We use about 450 faults in the western United States (WUS) and derive recurrence times from either geologic slip rates or the dating of pre-historic earthquakes from trenching of faults or other paleoseismic methods. Recurrence estimates for large earthquakes in New Madrid and Charleston, South Carolina, were taken from recent paleoliquefaction studies. We used logic trees to incorporate different seismicity models, fault recurrence models, Cascadia great earthquake scenarios, and ground-motion attenuation relations. We present disaggregation plots showing the contribution to hazard at four cities from potential earthquakes with various magnitudes and

  16. Mapping the Heart

    Science.gov (United States)

    Hulse, Grace

    2012-01-01

    In this article, the author describes how her fourth graders made ceramic heart maps. The impetus for this project came from reading "My Map Book" by Sara Fanelli. This book is a collection of quirky, hand-drawn and collaged maps that diagram a child's world. There are maps of her stomach, her day, her family, and her heart, among others. The…

  17. Mapping the Heart

    Science.gov (United States)

    Hulse, Grace

    2012-01-01

    In this article, the author describes how her fourth graders made ceramic heart maps. The impetus for this project came from reading "My Map Book" by Sara Fanelli. This book is a collection of quirky, hand-drawn and collaged maps that diagram a child's world. There are maps of her stomach, her day, her family, and her heart, among others. The…

  18. USGS Map Indices Overlay Map Service from The National Map

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS Map Indices service from The National Map (TNM) consists of 1x1 Degree, 30x60 Minute (100K), 15 Minute (63K), 7.5 Minute (24K), and 3.75 Minute grid...

  19. VEGETATION MAPPING IN WETLANDS

    Directory of Open Access Journals (Sweden)

    F. PEDROTTI

    2004-01-01

    Full Text Available The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of vegetation series.

  20. -Deformed nonlinear maps

    Indian Academy of Sciences (India)

    Ramaswamy Jaganathan; Sudeshna Sinha

    2005-03-01

    Motivated by studies on -deformed physical systems related to quantum group structures, and by the elements of Tsallis statistical mechanics, the concept of -deformed nonlinear maps is introduced. As a specific example, a -deformation procedure is applied to the logistic map. Compared to the canonical logistic map, the resulting family of -logistic maps is shown to have a wider spectrum of interesting behaviours, including the co-existence of attractors – a phenomenon rare in one-dimensional maps.

  1. Google Maps: You Are Here

    Science.gov (United States)

    Jacobsen, Mikael

    2008-01-01

    Librarians use online mapping services such as Google Maps, MapQuest, Yahoo Maps, and others to check traffic conditions, find local businesses, and provide directions. However, few libraries are using one of Google Maps most outstanding applications, My Maps, for the creation of enhanced and interactive multimedia maps. My Maps is a simple and…

  2. Web Mapping Using Logo on Map

    Directory of Open Access Journals (Sweden)

    Ximing Hou

    2012-12-01

    Full Text Available The newly proposed Logo on Map (LoM system consists of three modules: picture extraction module (PEM, logo matching module (LMM and web mapping module (WMM. Since the first two modules were covered in our previous paper, the third module WMM is described here to present a complete LoM system. Current research is focused on geo-location distribution of brands on Google Maps. Pictures taken by ordinary people are extracted using Picture Extraction Module (PEM. The pictures containing relevant logos are obtained via Logo Matching Module (LMM. Brand distributions are overlaid on Google Maps. In this paper, GPS and brands are briefly described, and the implementation of Web Mapping Module (WMM based on Google Maps API is detailed. Then several experiments are carried out on the selected top brands. Finally the LMM-pictures are mapped on the Google Maps and the geographical distributions of the brands are visualised. Brand uniqueness is discussed and conclusion is drawn that with unique brand names web mapping can visually reflect the real economic activities of a company in the world.

  3. Albedo and color maps of the Saturnian satellites

    Science.gov (United States)

    Buratti, Bonnie J.; Mosher, Joel A.; Johnson, Torrence V.

    1990-01-01

    The paper discusses the production of maps of the albedos and colors of Mimas, Enceladus, Tethys, Dione, and Rhea over the full range of their imaged surfaces. Voyager images were used to prepare maps of the normal reflectances and color ratios (0.58/0.41 micron) of these satelites.

  4. Albedo and color maps of the Saturnian satellites

    Energy Technology Data Exchange (ETDEWEB)

    Buratti, B.J.; Mosher, J.A.; Johnson, T.V. (JPL, Pasadena, CA (USA))

    1990-10-01

    The paper discusses the production of maps of the albedos and colors of Mimas, Enceladus, Tethys, Dione, and Rhea over the full range of their imaged surfaces. Voyager images were used to prepare maps of the normal reflectances and color ratios (0.58/0.41 micron) of these satelites. 67 refs.

  5. Modelling and mapping of critical thresholds in Europe

    NARCIS (Netherlands)

    Posch M; de Smet PAM; Hettelingh JP; Downing RJ; MNV

    2001-01-01

    This report is the sixth in a bi-annual series prepared by the Coordination Center for Effects (CCE) to document the progress made in calculating and mapping critical loads in Europe. The CCE, as part of the Mapping Programme under the UN/ECE Working Group on Effects (WGE), develops methodologies a

  6. Monitoring Of Water Logged Areas in Krishana Canal Command Using Gis Techniques

    Directory of Open Access Journals (Sweden)

    Dr. Santosh Bhailume

    2016-09-01

    Full Text Available Degradation of land due to waterlogging in sugarcane track of western Maharashtra is a serious problem. Here researchers had understood the problem of the waterlogged areas by preparing an inventory using GIS and GPS techniques. Krishna Canal Command area is lies in Satara and Sangli districts. Total length of canal is 86 km, out of which 21 km length is comes under study area. The command area is divided in 4 segments, out of which, the present study deals with Segment IV. Water table map was prepared using water depth data at 231 well locations. The entire analysis was carried out in ArcGIS software. GIS – Spatial Analysis tool, point data was rasterised, and surfaces for water table were generated. Risk zonation maps were prepared using the critical limits given by IRD, Pune. Water table surface was intersected with village boundary layers. Risk zonation map of water table suggests that the two villages namely Nagral and Burli situated close to canal are most vulnerable due to high water table. Almost 36 % of the total study area of land covering partially the villages Nagral, Burli, Shirasgaon, Amnapur, Palus, and Yelavi were found under critical water table condition. In segment IV total area of 792 ha in villages Nagral, Burli, Amnapur, Yelavi, and Bhilawadi fall under the P1 category affected most badly by the waterlogging condition. Prioritization of villages based on AWI suggests that out of the total eight villages, five villages namely Amnapur, Burli, Bhilawadi, Nagral and Yelavi are falling under P1 priority category, need immediate attention for remedial measures

  7. Mapping with Drupal

    CERN Document Server

    Palazzolo, Alan

    2011-01-01

    Build beautiful interactive maps on your Drupal website, and tell engaging visual stories with your data. This concise guide shows you how to create custom geographical maps from top to bottom, using Drupal 7 tools and out-of-the-box modules. You'll learn how mapping works in Drupal, with examples on how to use intuitive interfaces to map local events, businesses, groups, and other custom data. Although building maps with Drupal can be tricky, this book helps you navigate the system's complexities for creating sophisticated maps that match your site design. Get the knowledge and tools you ne

  8. Coded MapReduce

    OpenAIRE

    Li, Songze; Maddah-Ali, Mohammad Ali; Avestimehr, A. Salman

    2015-01-01

    MapReduce is a commonly used framework for executing data-intensive jobs on distributed server clusters. We introduce a variant implementation of MapReduce, namely "Coded MapReduce", to substantially reduce the inter-server communication load for the shuffling phase of MapReduce, and thus accelerating its execution. The proposed Coded MapReduce exploits the repetitive mapping of data blocks at different servers to create coding opportunities in the shuffling phase to exchange (key,value) pair...

  9. Some Semi - Equivelar Maps

    CERN Document Server

    Upadhyay, Ashish K; Maity, Dipendu

    2011-01-01

    Semi-Equivelar maps are generalizations of Archimedean Solids (as are equivelar maps of the Platonic solids) to the surfaces other than $2-$Sphere. We classify some semi equivelar maps on surface of Euler characteristic -1 and show that none of these are vertex transitive. We establish existence of 12-covered triangulations for this surface. We further construct double cover of these maps to show existence of semi-equivelar maps on the surface of double torus. We also construct several semi-equivelar maps on the surfaces of Euler characteristics -8 and -10 and on non-orientable surface of Euler characteristics -2.

  10. Mapping in the cloud

    CERN Document Server

    Peterson, Michael P

    2014-01-01

    This engaging text provides a solid introduction to mapmaking in the era of cloud computing. It takes students through both the concepts and technology of modern cartography, geographic information systems (GIS), and Web-based mapping. Conceptual chapters delve into the meaning of maps and how they are developed, covering such topics as map layers, GIS tools, mobile mapping, and map animation. Methods chapters take a learn-by-doing approach to help students master application programming interfaces and build other technical skills for creating maps and making them available on the Internet. Th

  11. Parabolic-like maps

    CERN Document Server

    Lomonaco, Luciana Luna Anna

    2011-01-01

    In this paper we introduce the notion of parabolic-like mapping, which is an object similar to a polynomial-like mapping, but with a parabolic external class, i.e. an external map with a parabolic fixed point. We prove a straightening theorem for parabolic-like maps, which states that any parabolic-like map of degree 2 is hybrid conjugate to a member of the family Per_1(1), and this member is unique (up to holomorphic conjugacy) if the filled Julia set of the parabolic-like map is connected.

  12. Meso(topoclimatic maps and mapping

    Directory of Open Access Journals (Sweden)

    Ladislav Plánka

    2007-06-01

    Full Text Available The atmospheric characteristics can be studied from many points of view, most often we talk about time and spatial standpoint. Application of time standpoint leads either to different kinds of the synoptic and prognostic maps production, which presents actual state of atmosphere in short time section in the past or in the near future or to the climatic maps production which presents longterm weather regime. Spatial standpoint then differs map works according to natural phenomenon proportions, whereas the scale of their graphic presentation can be different. It depends on production purpose of each work.In the paper there are analysed methods of mapping and climatic maps production, which display longterm regime of chosen atmospheric features. These athmosphere features are formed in interaction with land surface and also have direct influence on people and their activities throughout the country. At the same time they’re influenced by anthropogenic intervention to the landscape.

  13. Geologic Maps and Cross Sections of the Tuba City Open Dump Site and Vicinity, With Implications for the Occurrence and Flow of Ground Water

    Science.gov (United States)

    Otton, James K.; Johnson, Ray H.; Horton, Robert J.

    2008-01-01

    This report is designed to make available to interested parties geologic and limited hydrologic and geochemical information about the Tuba City Open Dump (TCOD) site. This information has been gathered during studies of the site from January to September 2008. Mapping by the authors and construction of cross sections show that a section of gently northeast-dipping Jurassic sedimentary rocks underlies the TCOD and vicinity. Low mesas in the area are capped by variably cemented gravels and siliceous limestones. Surficial sediments are composed of eolian sand and fluvially reworked eolian sand that overlie bedrock underneath the TCOD. Nearby Pasture Canyon is underlain by fluvial and floodplain sediment consisting of sand and silt. Shallow ground water of the water-table aquifer at the TCOD moves westward through the surficial sediment and the underlying weathered bedrock to Pasture Canyon then southward along the canyon. A fracture zone extends up the wash that passes just to the north of the TCOD and brings deeper ground water of the N-aquifer to the water-table aquifer. Bedrock consists of the Jurassic Navajo Sandstone composed of thick sections of eolian crossbedded sandstone with lesser laterally discontinuous layers of silty sandstone, siltstone, and limestone. Below the Navajo Sandstone is a section informally known as the Kayenta Formation-Navajo Sandstone transition zone. It is composed of calcareous sandstone, silty sandstone, siltstone, and limestone beds that intertongue with crossbedded sandstone. The finer grained rocks in both major bedrock units form aquitards that limit downward movement of ground water. The water-table aquifer is perched on these aquitards, which locally occurs beneath the two open dumps that form the TCOD site. A monocline occupies the position of Pasture Canyon west of the TCOD. Fractures likely related to the monocline are exposed in several localities. Deep ground waters consist of dilute calcium-bicarbonate waters low in all

  14. Recovery Action Mapping Tool

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Recovery Action Mapping Tool is a web map that allows users to visually interact with and query actions that were developed to recover species listed under the...

  15. Mapping Medicare Disparities Tool

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CMS Office of Minority Health has designed an interactive map, the Mapping Medicare Disparities Tool, to identify areas of disparities between subgroups of...

  16. NAIP Status Maps Gallery

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — NAIP Status Maps Gallery. These maps illustrate what aerial imagery collection is planned, whats been collected, when it is available and how it is available. These...

  17. NGS Survey Control Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Survey Control Map provides a map of the US which allows you to find and display geodetic survey control points stored in the database of the National...

  18. Letter of Map Revision

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  19. Improving wetland mapping techniques

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Mapping wetland extent, structure and invasives using radar imagery. Acquiring optical, thermal, LIDAR, and RADAR images and analysis for improved wetland mapping,...

  20. MapBook

    Data.gov (United States)

    National Aeronautics and Space Administration — Beginning with the systematic mapping of the lunar surface more than three decades ago, this database contains over 1600 maps of the planets and satellites of the...

  1. Invariants for Parallel Mapping

    Institute of Scientific and Technical Information of China (English)

    YIN Yajun; WU Jiye; FAN Qinshan; HUANG Kezhi

    2009-01-01

    This paper analyzes the geometric quantities that remain unchanged during parallel mapping (i.e., mapping from a reference curved surface to a parallel surface with identical normal direction). The second gradient operator, the second class of integral theorems, the Gauss-curvature-based integral theorems, and the core property of parallel mapping are used to derive a series of parallel mapping invadants or geometri-cally conserved quantities. These include not only local mapping invadants but also global mapping invari-ants found to exist both in a curved surface and along curves on the curved surface. The parallel mapping invadants are used to identify important transformations between the reference surface and parallel surfaces. These mapping invadants and transformations have potential applications in geometry, physics, biome-chanics, and mechanics in which various dynamic processes occur along or between parallel surfaces.

  2. Mapping Mutations on Phylogenies

    DEFF Research Database (Denmark)

    Nielsen, Rasmus

    2005-01-01

    This chapter provides a short review of recent methodologies developed for mapping mutations on phylogenies. Mapping of mutations, or character changes in general, using the maximum parsimony principle has been one of the most powerful tools in phylogenetics, and it has been used in a variety...... of different applications, for example, in the detection of correlated evolution and to identify selection acting on DNA sequences. However, many uses of parsimony mappings have been criticized because they focus on only one of many possible mappings and/or because they do not incorporate statistical...... uncertainty in the mapping. Recently developed probabilistic methods can incorporate statistical uncertainty in the character mappings. In these methods, focus is on a probability distribution of mutational mappings instead of a single estimate of the mutational mapping....

  3. Active Fire Mapping Program

    Science.gov (United States)

    Active Fire Mapping Program Current Large Incidents (Home) New Large Incidents Fire Detection Maps MODIS Satellite Imagery VIIRS Satellite Imagery Fire Detection GIS Data Fire Data in Google Earth ...

  4. Lying with Maps

    OpenAIRE

    Monmonier, Mark

    2005-01-01

    Darrell Huff’s How to Lie with Statistics was the inspiration for How to Lie with Maps, in which the author showed that geometric distortion and graphic generalization of data are unavoidable elements of cartographic representation. New examples of how ill-conceived or deliberately contrived statistical maps can greatly distort geographic reality demonstrate that lying with maps is a special case of lying with statistics. Issues addressed include the effects of map scale on geometry and featu...

  5. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Olsen, Ole Fogh; Sporring, Jon

    2006-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......, while eliminating noise. We call our method diffusion based photon mapping....

  6. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Fogh Olsen, Ole; Sporring, Jon

    2007-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......, while eliminating noise. We call our method diffusion based photon mapping....

  7. Reading Angles in Maps

    Science.gov (United States)

    Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.

    2014-01-01

    Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…

  8. Curriculum Mapping. Focus On

    Science.gov (United States)

    Molineaux, Rebecca

    2008-01-01

    This "Focus On" discusses curriculum mapping, a process that allows educators to align the curriculum both within and across grades and to ensure that the curriculum is in line with school, local, and state standards. It outlines the steps of the curriculum mapping process from planning the mapping initiative to creating and editing curriculum…

  9. Mapping a Changing World.

    Science.gov (United States)

    Stoltman, Joseph P.

    1992-01-01

    Addresses the importance of maps for instruction in both history and geography. Suggests that maps have gotten recent attention because of the rapid political changes occurring in Europe and the quincentenary of Columbus' voyage. Discusses different map projections and the importance of media and satellite display of real pictures of the world.…

  10. Branched polynomial covering maps

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    1999-01-01

    A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

  11. Branched polynomial covering maps

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    2002-01-01

    A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

  12. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  13. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  14. Research on irrigation schedule of cotton drip irrigation under plastic film based on the different ground water table in arid areas%干旱区不同地下水埋深膜下滴灌灌溉制度模拟研究

    Institute of Scientific and Technical Information of China (English)

    杨鹏年; 吴彬; 王水献; 董新光; 刘磊

    2014-01-01

    Through the irrigation schedule experiment of drip irrigation cotton under plastic film in Korla Irrigation Experiment Station ,Xinjiang ,has obtained the suitable local conventional drip irrigation schedule .In order to further study the compensation effect of shallow groundwater to the irrigation ,we use the Hydrus software to simulate the water consumption in growing stage of drip irrigation cotton under plastic film with different groundwater table .Through dwaw-ing into the concept of key point soil water content ,put forward the criterion of cotton water stress by the drip irrigation under plastic film .The results showed that :The ground water has a certain compensating function for the cotton water consumption ,the shallower groundwater table ,the smaller irrigation quota required .When the groundwater table was less than 1 .5 m ,the drip irrigation quota was 3300 m3·hm-2 .When the groundwater table was 2 .0 m ,the drip irrigation quota was 4500 m3·hm-2 .When the groundwater table was so biger and no any compensation ,the cotton growth totally rely on the drip irrigation ,the drip irrigation quota was 5550 m3·hm-2 .Consided the high evaporation potential in the arid area ,it will cause the soil salinity to damage crop growth ,the ground water table of 1 .5 m to 3 .0 m was the desired depth .This conclusion is not only the complementary and improvement to the conventional cotton irrigation schedule ,but also this proposed method will have the guide and reference role for management and establishing the crop consumption quota of drip irrigation under plastic film in arid area .%通过在新疆巴州灌溉试验站进行的膜下滴灌棉花灌溉制度试验,得出了适合当地的常规滴灌制度。为进一步研究浅层地下水对灌溉的补偿效应,利用Hydrus软件对不同地下水埋深下膜下滴灌棉花生育期耗水量进行了模拟。通过引入关键点土壤含水率的概念,提出了膜下滴灌棉花受水分胁迫的标

  15. Transmittance spectroscopy and transmitted multispectral imaging to map covered paints

    Directory of Open Access Journals (Sweden)

    Antonino Cosentino

    2016-01-01

    Full Text Available Transmitted spectroscopy and transmitted multispectral imaging in the 400-900 nm range have been applied for the mapping and tentative identification of paints covered by a white preparation as in the case of a ground laid for reusing a canvas for another painting. These methods can be applied to polychrome works of art, as long as their support and new preparation are sufficiently translucent. This work presents the transmittance spectra acquired from a test board consisting of a prepared canvas with swatches of 54 pigments covered with titanium white and the multispectral images realized with transmitted light to map covered paints on a mock-up painting. It was observed that 18 out of 54 historical pigments provide characteristic transmittance spectra even underneath a titanium white preparation layer and that transmitted light multispectral imaging can map hidden paint layers.

  16. Flood Hazard Mapping by Using Geographic Information System and Hydraulic Model: Mert River, Samsun, Turkey

    Directory of Open Access Journals (Sweden)

    Vahdettin Demir

    2016-01-01

    Full Text Available In this study, flood hazard maps were prepared for the Mert River Basin, Samsun, Turkey, by using GIS and Hydrologic Engineering Centers River Analysis System (HEC-RAS. In this river basin, human life losses and a significant amount of property damages were experienced in 2012 flood. The preparation of flood risk maps employed in the study includes the following steps: (1 digitization of topographical data and preparation of digital elevation model using ArcGIS, (2 simulation of flood lows of different return periods using a hydraulic model (HEC-RAS, and (3 preparation of flood risk maps by integrating the results of (1 and (2.

  17. Spatiotemporal brain mapping during preparation, perception, and action.

    Science.gov (United States)

    Di Russo, Francesco; Lucci, Giuliana; Sulpizio, Valentina; Berchicci, Marika; Spinelli, Donatella; Pitzalis, Sabrina; Galati, Gaspare

    2016-02-01

    Deciding whether to act or not to act is a fundamental cognitive function. To avoid incorrect responses, both reactive and proactive modes of control have been postulated. Little is known, however, regarding the brain implementation of proactive mechanisms, which are deployed prior to an actual need to inhibit a response. Via a combination of electrophysiological and neuroimaging measures (recorded in 21 and 16 participants, respectively), we describe the brain localization and timing of neural activity that underlies the anticipatory proactive mechanism. From these results, we conclude that proactive control originates in the inferior Frontal gyrus, is established well before stimulus perception, and is released concomitantly with stimulus appearance. Stimulus perception triggers early activity in the anterior insula and intraparietal cortex contralateral to the responding hand; these areas likely mediate the transition from perception to action. The neural activities leading to the decision to act or not to act are described in the framework of a three-stage model that includes perception, action, and anticipatory functions taking place well before stimulus onset.

  18. Cosmopolitan linkage disequilibrium maps

    Directory of Open Access Journals (Sweden)

    Gibson Jane

    2005-03-01

    Full Text Available Abstract Linkage maps have been invaluable for the positional cloning of many genes involved in severe human diseases. Standard genetic linkage maps have been constructed for this purpose from the Centre d'Etude du Polymorphisme Humain and other panels, and have been widely used. Now that attention has shifted towards identifying genes predisposing to common disorders using linkage disequilibrium (LD and maps of single nucleotide polymorphisms (SNPs, it is of interest to consider a standard LD map which is somewhat analogous to the corresponding map for linkage. We have constructed and evaluated a cosmopolitan LD map by combining samples from a small number of populations using published data from a 10-megabase region on chromosome 20. In support of a pilot study, which examined a number of small genomic regions with a lower density of markers, we have found that a cosmopolitan map, which serves all populations when appropriately scaled, recovers 91 to 95 per cent of the information within population-specific maps. Recombination hot spots appear to have a dominant role in shaping patterns of LD. The success of the cosmopolitan map might be attributed to the co-localisation of hot spots in all populations. Although there must be finer scale differences between populations due to other processes (mutation, drift, selection, the results suggest that a whole-genome standard LD map would indeed be a useful resource for disease gene mapping.

  19. Angola Seismicity MAP

    Science.gov (United States)

    Neto, F. A. P.; Franca, G.

    2014-12-01

    The purpose of this job was to study and document the Angola natural seismicity, establishment of the first database seismic data to facilitate consultation and search for information on seismic activity in the country. The study was conducted based on query reports produced by National Institute of Meteorology and Geophysics (INAMET) 1968 to 2014 with emphasis to the work presented by Moreira (1968), that defined six seismogenic zones from macro seismic data, with highlighting is Zone of Sá da Bandeira (Lubango)-Chibemba-Oncócua-Iona. This is the most important of Angola seismic zone, covering the epicentral Quihita and Iona regions, geologically characterized by transcontinental structure tectono-magmatic activation of the Mesozoic with the installation of a wide variety of intrusive rocks of ultrabasic-alkaline composition, basic and alkaline, kimberlites and carbonatites, strongly marked by intense tectonism, presenting with several faults and fractures (locally called corredor de Lucapa). The earthquake of May 9, 1948 reached intensity VI on the Mercalli-Sieberg scale (MCS) in the locality of Quihita, and seismic active of Iona January 15, 1964, the main shock hit the grade VI-VII. Although not having significant seismicity rate can not be neglected, the other five zone are: Cassongue-Ganda-Massano de Amorim; Lola-Quilengues-Caluquembe; Gago Coutinho-zone; Cuima-Cachingues-Cambândua; The Upper Zambezi zone. We also analyzed technical reports on the seismicity of the middle Kwanza produced by Hidroproekt (GAMEK) region as well as international seismic bulletins of the International Seismological Centre (ISC), United States Geological Survey (USGS), and these data served for instrumental location of the epicenters. All compiled information made possible the creation of the First datbase of seismic data for Angola, preparing the map of seismicity with the reconfirmation of the main seismic zones defined by Moreira (1968) and the identification of a new seismic

  20. Thematic Working Map in GIS Environment

    Directory of Open Access Journals (Sweden)

    Stjepan Husnjak

    2003-03-01

    Full Text Available Planning of sustainable development and land use requires a lot of reliable and good quality information, which serves as the basis for timely and adequate decision-making. One of the most important forms of information are various maps. Until recently, preparing of such data was, no doubt, a rather complex. At present thanks to first of all, the GIS technology it is possible to develop corresponding geographic information systems with databases which then allow comparatively simple preparing of necessary thematic maps.The paper first presents the method of developing the Geographic and Land Information System(GIZIS of the Karlovacka County which, although developed for the purpose of agricultural development, may also be used in ecology, environment protection, physical planning, water management and for soil conservation and regulation. Several examples illustrate the possibilities of preparing of specialized maps. The basic data for developing of the geographic and land information system were the data of the Basic Soil Maps and topographic maps of the Republic ofCroatia at the scale of 1:50 000 or 1:25 000, and the data from other studies made for the purpose of agricultural development in the area. These data, together with the results of processing and analysis this data, by digitalization, generalization and interpolation, were incorporated into an integrated database of the geographic and land information system by using Microstation, AutoCad, ArcInfo, ArcWiew and Access software and the corresponding hardware. GIZIS database consists of two parts. The first part includes the data referring to polygons - pedological contours, and the other part the data on pedological profiles. The base is organized in a way that enable prepare different thematic maps, but it can be also used in digital form allowing simple and easy access by the ArcWiew program package to all information, either by the base search or by putting questions. The data

  1. On palaeogeographic map

    Directory of Open Access Journals (Sweden)

    Zeng-Zhao Feng

    2016-01-01

    Full Text Available The palaeogeographic map is a graphic representation of physical geographical characteristics in geological history periods and human history periods. It is the most important result of palaeogeographic study. The author, as the Editor-in-Chief of Journal of Palaeogeography, Chinese Edition and English Edition, aimed at the problems of the articles submitted to and published in the Journal of Palaeogeography in recent years and the relevant papers and books of others, and integrated with his practice of palaeogeographic study and mapping, wrote this paper. The content mainly includes the data of palaeogeographic mapping, the problems of palaeogeographic mapping method, the “Single factor analysis and multifactor comprehensive mapping method —— Methodology of quantitative lithofacies palaeogeography”, i.e., the “4 steps mapping method”, the nomenclature of each palaeogeographic unit in palaeogeographic map, the explanation of each palaeogeographic unit in palaeogeographic map, the explanation of significance of palaeogeographic map and palaeogeographic article, the evaluative standards of palaeogeographic map and palaeogeographic article, and the self-evaluation. Criticisms and corrections are welcome.

  2. Mapping Weak, Altered Zones and Perched Water With Aerogeophysical Measurements at Mount Adams, Washington: Implications for Volcanic Instability

    Science.gov (United States)

    Finn, C. A.; Deszcz-Pan, M.; Anderson, E. D.; Horton, R.

    2006-12-01

    Hydrothermally altered rocks, particularly if water saturated, can weaken stratovolcanoes. This increases the potential for catastrophic sector collapses that can lead to destructive debris flows. Evaluating the hazards associated with such alteration is difficult, because alteration has been mapped on few active volcanoes and the distribution and intensity of subsurface alteration and location of perched water tables are largely unknown on any active volcano. At Mount Adams, some Holocene debris flows contain abundant hydrothermal minerals derived from collapse of an altered edifice. Intense hydrothermal alteration can significantly reduce the resistivity (from hundreds to tens ohm-m) and magnetization of volcanic rocks. These changes can be identified with helicopter electromagnetic and magnetic measurements and visualized in 3D. 100 m is the greatest depth that the lowest frequency electromagnetic data could penetrate into the low resistivity, altered zones; outside the altered zones, the depth of penetration was up to 300 m. Total-field magnetic data can detect magnetization variations to several thousand meters depth. Electromagnetic and magnetic data, combined with geological mapping and rock property measurements, indicate the presence of appreciable thicknesses of hydrothermally altered rock in the central core of Mount Adams north of the summit. We identify steep cliffs at the western edge of this zone as the likely source for future large debris flows. Water, and perhaps melted ice, is needed as a lubricant to transform debris avalanches into lahars. Therefore, knowing the distribution of both is important for hazard assessments. Over the low resistivity summit, the electromagnetic data detected ice with a thickness of 0 to about 80 m and an estimated volume of up to 0.1 km3. Over resistive ridges ice thicknesses could not be determined. The electromagnetic data also identified perched water tables in the brecciated core of the upper 300 m of the volcano

  3. Interactive map of refugee movement in Europe

    Directory of Open Access Journals (Sweden)

    Calka Beata

    2016-12-01

    Full Text Available Considering the recent mass movement of people fleeing war and oppression, an analysis of changes in migration, in particular an analysis of the final destination refugees choose, seems to be of utmost importance. Many international organisations like UNHCR (the United Nations High Commissioner for Refugees or EuroStat gather and provide information on the number of refugees and the routes they follow. What is also needed to study the state of affairs closely is a visual form presenting the rapidly changing situation. An analysis of the problem together with up-to-date statistical data presented in the visual form of a map is essential. This article describes methods of preparing such interactive maps displaying movement of refugees in European Union countries. Those maps would show changes taking place throughout recent years but also the dynamics of the development of the refugee crisis in Europe. The ArcGIS software was applied to make the map accessible on the Internet. Additionally, online sources and newspaper articles were used to present the movement of migrants. The interactive map makes it possible to watch spatial data with an opportunity to navigate within the map window. Because of that it is a clear and convenient tool to visualise such processes as refugee migration in Europe.

  4. Interactive map of refugee movement in Europe

    Science.gov (United States)

    Calka, Beata; Cahan, Bruce

    2016-12-01

    Considering the recent mass movement of people fleeing war and oppression, an analysis of changes in migration, in particular an analysis of the final destination refugees choose, seems to be of utmost importance. Many international organisations like UNHCR (the United Nations High Commissioner for Refugees) or EuroStat gather and provide information on the number of refugees and the routes they follow. What is also needed to study the state of affairs closely is a visual form presenting the rapidly changing situation. An analysis of the problem together with up-to-date statistical data presented in the visual form of a map is essential. This article describes methods of preparing such interactive maps displaying movement of refugees in European Union countries. Those maps would show changes taking place throughout recent years but also the dynamics of the development of the refugee crisis in Europe. The ArcGIS software was applied to make the map accessible on the Internet. Additionally, online sources and newspaper articles were used to present the movement of migrants. The interactive map makes it possible to watch spatial data with an opportunity to navigate within the map window. Because of that it is a clear and convenient tool to visualise such processes as refugee migration in Europe.

  5. Absorption mapping for characterization of glass surfaces.

    Science.gov (United States)

    Commandré, M; Roche, P; Borgogno, J P; Albrand, G

    1995-05-01

    The surface quality of bare substrates and preparation procedures take on an important role in optical coating performances. The most commonly used techniques of characterization generally give information about roughness and local defects. A photothermal deflection technique is used for mapping surface absorption of fused-silica and glass substrates. We show that absorption mapping gives specific information on surface contamination of bare substrates. We present experimental results concerning substrates prepared by different cleaning and polishing techniques. We show that highly polished surfaces lead to the lowest values of residual surface absorption. Moreover the cleaning behavior of surfaces of multicomponent glasses and their optical performance in terms of absorption are proved to be different from those of fused silica.

  6. Map Projection Transitions

    Directory of Open Access Journals (Sweden)

    Nedjeljko Frančula

    2013-06-01

    Full Text Available Map Projection Transitions is a very successful web application about map projections. The web page (http://www.jasondavies.com/maps/transition pre­sents a world map with graticule and country borders in the oblique Aitoff projection, with the South Pole. The map is not static, but animated. The South Pole moves toward the bottom and Earth rotates around its poles. The animation lasts five seconds, after which the projection changes and movement continues for five seconds, after which the projection changes again. Names of projections appear in a separate window. There are a total of 56 projections. The South Pole eventually becomes invisible and the North Pole appears at the top. Various parts of Earth appear in the center of the map by rotating around the poles.

  7. Multi-moment maps

    DEFF Research Database (Denmark)

    Swann, Andrew Francis; Madsen, Thomas Bruun

    2012-01-01

    We introduce a notion of moment map adapted to actions of Lie groups that preserve a closed three-form. We show existence of our multi-moment maps in many circumstances, including mild topological assumptions on the underlying manifold. Such maps are also shown to exist for all groups whose secon......-torus symmetry in terms of tri-symplectic geometry of four-manifolds. (C) 2012 Elsevier Inc. All rights reserved....

  8. Classification of Lipschitz mappings

    CERN Document Server

    Piasecki, Lukasz

    2013-01-01

    The Lipschitz Condition Nonlinear spectral radius Uniformly lipschitzian mappings Basic Facts on Banach Spaces Convexity The operator norm Dual spaces, reexivity, the weak, and weak* topologiesMean Lipschitz Condition Nonexpansive and mean nonexpansive mappings in Banach spaces General case On the Lipschitz Constants for Iterates of Mean Lipschitzian Mappings A bound for Lipschitz constants of iterates A bound for the constant k∞(T)Moving averages in Bana

  9. On probabilistic Mandelbrot maps

    Energy Technology Data Exchange (ETDEWEB)

    Andreadis, Ioannis [International School of The Hague, Wijndaelerduin 1, 2554 BX The Hague (Netherlands)], E-mail: i.andreadis@ish-rijnlandslyceum.nl; Karakasidis, Theodoros E. [Department of Civil Engineering, University of Thessaly, GR-38334 Volos (Greece)], E-mail: thkarak@uth.gr

    2009-11-15

    In this work, we propose a definition for a probabilistic Mandelbrot map in order to extend and support the study initiated by Argyris et al. [Argyris J, Andreadis I, Karakasidis Th. On perturbations of the Mandelbrot map. Chaos, Solitons and Fractals 2000;11:1131-1136.] with regard to the numerical stability of the Mandelbrot and Julia set of the Mandelbrot map when subjected to noise.

  10. Similarity transformations of MAPs

    Directory of Open Access Journals (Sweden)

    Andersen Allan T.

    1999-01-01

    Full Text Available We introduce the notion of similar Markovian Arrival Processes (MAPs and show that the event stationary point processes related to two similar MAPs are stochastically equivalent. This holds true for the time stationary point processes too. We show that several well known stochastical equivalences as e.g. that between the H 2 renewal process and the Interrupted Poisson Process (IPP can be expressed by the similarity transformations of MAPs. In the appendix the valid region of similarity transformations for two-state MAPs is characterized.

  11. Obesity Prevalence Maps

    Science.gov (United States)

    ... Breastfeeding Micronutrient Malnutrition State and Local Programs Adult Obesity Prevalence Maps Recommend on Facebook Tweet Share Compartir Obesity Prevalence in 2016 by Education and Age Obesity ...

  12. Supporting Worth Mapping with Sentence Completion

    Science.gov (United States)

    Cockton, Gilbert; Kujala, Sari; Nurkka, Piia; Hölttä, Taneli

    Expectations for design and evaluation approaches are set by the development practices within which they are used. Worth-Centred Development (WCD) seeks to both shape and fit such practices. We report a study that combined two WCD approaches. Sentence completion gathered credible quantitative data on user values, which were used to identify relevant values and aversions of two player groups for an on-line gambling site. These values provided human value elements for a complementary WCD approach of worth mapping. Initial worth maps were extended in three workshops, which focused on outcomes and user experiences that could be better addressed in the current product and associated marketing materials. We describe how worth maps were prepared for, and presented in, workshops, and how product owners and associated business roles evaluated the combination of WCD approaches. Based on our experiences, we offer practical advice on this combinination.

  13. Application of RgMap system on digital regional geological survey

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Digital geological mapping fundamentally broke through the traditional working pattern, successfully carried out the geological mapping digitalization. By using the RGMAP system to field digital geological mapping, the authors summarized the method of work and the work flow of the RGMAPGIS during the field geological survey. First, we prepared material, set up the PRB gallery, then put the geographic base map under the background maplayer and organizing the field hand map, forming the field factual datum map. At last, the geological space database is formed.

  14. Challenges in making a seismic hazard map for Alaska and the Aleutians

    Science.gov (United States)

    Wesson, R.L.; Boyd, O.S.; Mueller, C.S.; Frankel, A.D.; Freymueller, J.T.

    2008-01-01

    We present a summary of the data and analyses leading to the revision of the time-independent probabilistic seismic hazard maps of Alaska and the Aleutians. These maps represent a revision of existing maps based on newly obtained data, and reflect best current judgments about methodology and approach. They have been prepared following the procedures and assumptions made in the preparation of the 2002 National Seismic Hazard Maps for the lower 48 States, and will be proposed for adoption in future revisions to the International Building Code. We present example maps for peak ground acceleration, 0.2 s spectral amplitude (SA), and 1.0 s SA at a probability level of 2% in 50 years (annual probability of 0.000404). In this summary, we emphasize issues encountered in preparation of the maps that motivate or require future investigation and research.

  15. Occupancy Grid Map Merging Using Feature Maps

    Science.gov (United States)

    2010-11-01

    Gonzalez, “Toward a unified bayesian approach to hybrid metric-topological SLAM,” IEEE Transactions on Robotics , 24(2), April 2008, 259-270. [14] G...Risetti, C. Stachniss, and W. Burgard, “Improved Techniques for grid mapping with Rao-Blackwellized Particle Filter,” IEEE Transactions on Robotics , 23

  16. On circle map coupled map lattice

    CERN Document Server

    Ahmed, E

    2002-01-01

    Circle map in one and two dimensions is studied. Both its stability, synchronization using bounded control and persistence is discussed. This work is expected to be applicable in ecology where spatial effects are known to be important. Also it will be relevant to systems where delay effects are not negligible.

  17. A digital procedure for ground water recharge and discharge pattern recognition and rate estimation.

    Science.gov (United States)

    Lin, Yu-Feng; Anderson, Mary P

    2003-01-01

    A digital procedure to estimate recharge/discharge rates that requires relatively short preparation time and uses readily available data was applied to a setting in central Wisconsin. The method requires only measurements of the water table, fluxes such as stream baseflows, bottom of the system, and hydraulic conductivity to delineate approximate recharge/discharge zones and to estimate rates. The method uses interpolation of the water table surface, recharge/discharge mapping, pattern recognition, and a parameter estimation model. The surface interpolator used is based on the theory of radial basis functions with thin-plate splines. The recharge/discharge mapping is based on a mass-balance calculation performed using MODFLOW. The results of the recharge/discharge mapping are critically dependent on the accuracy of the water table interpolation and the accuracy and number of water table measurements. The recharge pattern recognition is performed with the help of a graphical user interface (GUI) program based on several algorithms used in image processing. Pattern recognition is needed to identify the recharge/discharge zonations and zone the results of the mapping method. The parameter estimation program UCODE calculates the parameter values that provide a best fit between simulated heads and flows and calibration head-and-flow targets. A model of the Buena Vista Ground Water Basin in the Central Sand Plains of Wisconsin is used to demonstrate the procedure.

  18. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Sporring, Jon; Fogh Olsen, Ole

    2008-01-01

    . To address this problem, we introduce a photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way, we preserve important illumination features, while...

  19. The Modern Geomorphological Map

    NARCIS (Netherlands)

    Seijmonsbergen, A.C.; Switzer, A.; Kennedy, D.M.

    2013-01-01

    Classical geomorphological maps are representations of the spatial distribution of landforms, materials and of the processes responsible for their formation, in a single paper map. They contain a wealth of information that is generally documented with the aid of symbol and color legends. Uniformity

  20. Android Mapping Application

    Directory of Open Access Journals (Sweden)

    Abdalwhab Bakheet

    2014-04-01

    Full Text Available Location-aware and mapping applications have gone f rom a desirable feature to an essential part of any smart phone. Whether a user is checking into a social network, looking for a pharmacy in the middle of the night, or located in somewhere and needs help, the key is always the same: location. In this project, an Android mapping application is developed. The application is able to display the map of the whole world while online or, display a pre-downloaded map while offline, track the user’s location, display a compass to determine north, send the user’s location to others in case of emergency using SMS, receive and interpret received location from the message, display it on the map, and notify the user by the reception of the location. The application was developed using agile methodol ogy. It, met its objectives and successfully passed 91% of the final system test, recording that some limitations were discovered, the application needs further testing and can be implem ented for particular company or university using their own maps or editing the maps in OSM (op en street maps.

  1. Map-A-Planet

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Map-A-Planet website allows users to create and download custom image maps of planets and satellites from a variety of missions in an easy to use web interface

  2. Simplifying Massive Contour Maps

    DEFF Research Database (Denmark)

    Arge, Lars; Deleuran, Lasse Kosetski; Mølhave, Thomas;

    2012-01-01

    We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours.......We present a simple, efficient and practical algorithm for constructing and subsequently simplifying contour maps from massive high-resolution DEMs, under some practically realistic assumptions on the DEM and contours....

  3. BenMAP Downloads

    Science.gov (United States)

    Download the current and legacy versions of the BenMAP program. Download configuration and aggregation/pooling/valuation files to estimate benefits. BenMAP-CE is free and open source software, and the source code is available upon request.

  4. Acoustic mapping velocimetry

    Science.gov (United States)

    Muste, M.; Baranya, S.; Tsubaki, R.; Kim, D.; Ho, H.; Tsai, H.; Law, D.

    2016-05-01

    Knowledge of sediment dynamics in rivers is of great importance for various practical purposes. Despite its high relevance in riverine environment processes, the monitoring of sediment rates remains a major and challenging task for both suspended and bed load estimation. While the measurement of suspended load is currently an active area of testing with nonintrusive technologies (optical and acoustic), bed load measurement does not mark a similar progress. This paper describes an innovative combination of measurement techniques and analysis protocols that establishes the proof-of-concept for a promising technique, labeled herein Acoustic Mapping Velocimetry (AMV). The technique estimates bed load rates in rivers developing bed forms using a nonintrusive measurements approach. The raw information for AMV is collected with acoustic multibeam technology that in turn provides maps of the bathymetry over longitudinal swaths. As long as the acoustic maps can be acquired relatively quickly and the repetition rate for the mapping is commensurate with the movement of the bed forms, successive acoustic maps capture the progression of the bed form movement. Two-dimensional velocity maps associated with the bed form migration are obtained by implementing algorithms typically used in particle image velocimetry to acoustic maps converted in gray-level images. Furthermore, use of the obtained acoustic and velocity maps in conjunction with analytical formulations (e.g., Exner equation) enables estimation of multidirectional bed load rates over the whole imaged area. This paper presents a validation study of the AMV technique using a set of laboratory experiments.

  5. Quaternionic versus complex maps

    Energy Technology Data Exchange (ETDEWEB)

    Asorey, M [Departamento de Fisica Teorica, Universidad de Zaragoza 50009 Zaragoza (Spain); Scolarici, G [Dipartimento di Fisica dell' Universita del Salento and INFN, Sezione di Lecce, I-73100 Lecce (Italy); Solombrino, L [Dipartimento di Fisica dell' Universita del Salento and INFN, Sezione di Lecce, I-73100 Lecce (Italy)

    2007-11-15

    We discuss the relation between completely positive quaternionic maps and the corresponding complex maps obtained via projection operation. In order to illustrate this formalism, we reobtain the (complex) qubit subdynamics of maximally entangled Bell states, as complex projection of unitary dynamics between quaternionic pure states.

  6. Statistical air quality mapping

    NARCIS (Netherlands)

    Kassteele, van de J.

    2006-01-01

    This thesis handles statistical mapping of air quality data. Policy makers require more and more detailed air quality information to take measures to improve air quality. Besides, researchers need detailed air quality information to assess health effects. Accurate and spatially highly resolved maps

  7. Pore size distribution mapping

    OpenAIRE

    Strange, John H.; J. Beau W. WEBBER; Schmidt, S.D.

    1996-01-01

    Pore size distribution mapping has been demonstrated using NMR cryoporometry\\ud in the presence of a magnetic field gradient, This novel method is extendable to 2D and 3D mapping. It offers a unique nondestructive method of obtaining full pore-size distributions in the range 3 to 100 nm at any point within a bulk sample. \\ud

  8. MUTYH Associated Polyposis (MAP)

    DEFF Research Database (Denmark)

    Poulsen, Marie Louise Mølgaard; Bisgaard, M L

    2008-01-01

    MUTYH Associated Polyposis (MAP), a Polyposis predisposition caused by biallelic mutations in the Base Excision Repair (BER) gene MUTYH, confers a marked risk of colorectal cancer (CRC). The MAP phenotype is difficult to distinguish from other hereditary CRC syndromes. Especially from Familial...

  9. Building Better Volcanic Hazard Maps Through Scientific and Stakeholder Collaboration

    Science.gov (United States)

    Thompson, M. A.; Lindsay, J. M.; Calder, E.

    2015-12-01

    All across the world information about natural hazards such as volcanic eruptions, earthquakes and tsunami is shared and communicated using maps that show which locations are potentially exposed to hazards of varying intensities. Unlike earthquakes and tsunami, which typically produce one dominant hazardous phenomenon (ground shaking and inundation, respectively) volcanic eruptions can produce a wide variety of phenomena that range from near-vent (e.g. pyroclastic flows, ground shaking) to distal (e.g. volcanic ash, inundation via tsunami), and that vary in intensity depending on the type and location of the volcano. This complexity poses challenges in depicting volcanic hazard on a map, and to date there has been no consistent approach, with a wide range of hazard maps produced and little evaluation of their relative efficacy. Moreover, in traditional hazard mapping practice, scientists analyse data about a hazard, and then display the results on a map that is then presented to stakeholders. This one-way, top-down approach to hazard communication does not necessarily translate into effective hazard education, or, as tragically demonstrated by Nevado del Ruiz, Columbia in 1985, its use in risk mitigation by civil authorities. Furthermore, messages taken away from a hazard map can be strongly influenced by its visual design. Thus, hazard maps are more likely to be useful, usable and used if relevant stakeholders are engaged during the hazard map process to ensure a) the map is designed in a relevant way and b) the map takes into account how users interpret and read different map features and designs. The IAVCEI Commission on Volcanic Hazards and Risk has recently launched a Hazard Mapping Working Group to collate some of these experiences in graphically depicting volcanic hazard from around the world, including Latin America and the Caribbean, with the aim of preparing some Considerations for Producing Volcanic Hazard Maps that may help map makers in the future.

  10. Map visualization of groundwater withdrawals at the sub-basin scale

    Science.gov (United States)

    Goode, Daniel J.

    2016-01-01

    A simple method is proposed to visualize the magnitude of groundwater withdrawals from wells relative to user-defined water-resource metrics. The map is solely an illustration of the withdrawal magnitudes, spatially centered on wells—it is not capture zones or source areas contributing recharge to wells. Common practice is to scale the size (area) of withdrawal well symbols proportional to pumping rate. Symbols are drawn large enough to be visible, but not so large that they overlap excessively. In contrast to such graphics-based symbol sizes, the proposed method uses a depth-rate index (length per time) to visualize the well withdrawal rates by volumetrically consistent areas, called “footprints”. The area of each individual well’s footprint is the withdrawal rate divided by the depth-rate index. For example, the groundwater recharge rate could be used as a depth-rate index to show how large withdrawals are relative to that recharge. To account for the interference of nearby wells, composite footprints are computed by iterative nearest-neighbor distribution of excess withdrawals on a computational and display grid having uniform square cells. The map shows circular footprints at individual isolated wells and merged footprint areas where wells’ individual footprints overlap. Examples are presented for depth-rate indexes corresponding to recharge, to spatially variable stream baseflow (normalized by basin area), and to the average rate of water-table decline (scaled by specific yield). These depth-rate indexes are water-resource metrics, and the footprints visualize the magnitude of withdrawals relative to these metrics.

  11. Mapping Prosopis spp. within the Tarach water basin, Turkana, Kenya using Sentinel-2 imagery

    Science.gov (United States)

    Ng, Wai-Tim; Immitzer, Markus; Floriansitz, Matthias; Vuolo, Francesco; Luminari, Luigi; Adede, Chrisgone; Wahome, Raphael; Atzberger, Clement

    2016-10-01

    Prosopis spp. are a fast growing invasive tree originating from the American dry zones, introduced to Kenya in the 1970s for the restoration of degraded pastoral lands after prolonged droughts and overgrazing. Its deep rooting system is capable of tapping into the ground water table reducing its dependency on rain water and increasing its drought tolerance. It is believed that the Prosopis invasion was eased by a hybridization process, described as the Prosopis Juliflora - Prosopis Pallida complex, suggesting that introduced Prosopis spp. evolved into a hybrid, specifically adapted to the environmental conditions, rendering it a superior and aggressive competitor to endemic species. In many dry lands in Kenya Prosopis has expanded rapidly and has become challenging to control. On the other hand, in some cases, an economic use seems possible. In both cases, detailed and accurate maps are necessary to support stakeholders and design management strategies. The aim of this study is to map the distribution of Prosopis spp. in a selected area in north-west Turkana (Kenya), covering a section of the Tarach water basin. The study is funded by the European Union through the National Drought Management Authority (NDMA) in Kenya, and the main purpose is to assess the potential production of Prosopis pods, which can be used to manufacture emergency livestock feeds to support animals during drought events. The classification was performed using novel Sentinel-2 data through a non-parametric Random Forest classifier. A selection of reference sites was visited in the field and used to train the classifier. Very high classification accuracies were obtained.

  12. Iconicity as structure mapping.

    Science.gov (United States)

    Emmorey, Karen

    2014-09-19

    Linguistic and psycholinguistic evidence is presented to support the use of structure-mapping theory as a framework for understanding effects of iconicity on sign language grammar and processing. The existence of structured mappings between phonological form and semantic mental representations has been shown to explain the nature of metaphor and pronominal anaphora in sign languages. With respect to processing, it is argued that psycholinguistic effects of iconicity may only be observed when the task specifically taps into such structured mappings. In addition, language acquisition effects may only be observed when the relevant cognitive abilities are in place (e.g. the ability to make structural comparisons) and when the relevant conceptual knowledge has been acquired (i.e. information key to processing the iconic mapping). Finally, it is suggested that iconicity is better understood as a structured mapping between two mental representations than as a link between linguistic form and human experience.

  13. Bodily maps of emotions.

    Science.gov (United States)

    Nummenmaa, Lauri; Glerean, Enrico; Hari, Riitta; Hietanen, Jari K

    2014-01-14

    Emotions are often felt in the body, and somatosensory feedback has been proposed to trigger conscious emotional experiences. Here we reveal maps of bodily sensations associated with different emotions using a unique topographical self-report method. In five experiments, participants (n = 701) were shown two silhouettes of bodies alongside emotional words, stories, movies, or facial expressions. They were asked to color the bodily regions whose activity they felt increasing or decreasing while viewing each stimulus. Different emotions were consistently associated with statistically separable bodily sensation maps across experiments. These maps were concordant across West European and East Asian samples. Statistical classifiers distinguished emotion-specific activation maps accurately, confirming independence of topographies across emotions. We propose that emotions are represented in the somatosensory system as culturally universal categorical somatotopic maps. Perception of these emotion-triggered bodily changes may play a key role in generating consciously felt emotions.

  14. The projective heat map

    CERN Document Server

    Schwartz, Richard Evan

    2017-01-01

    This book introduces a simple dynamical model for a planar heat map that is invariant under projective transformations. The map is defined by iterating a polygon map, where one starts with a finite planar N-gon and produces a new N-gon by a prescribed geometric construction. One of the appeals of the topic of this book is the simplicity of the construction that yet leads to deep and far reaching mathematics. To construct the projective heat map, the author modifies the classical affine invariant midpoint map, which takes a polygon to a new polygon whose vertices are the midpoints of the original. The author provides useful background which makes this book accessible to a beginning graduate student or advanced undergraduate as well as researchers approaching this subject from other fields of specialty. The book includes many illustrations, and there is also a companion computer program.

  15. Geologic map of Mars

    Science.gov (United States)

    Tanaka, Kenneth L.; Skinner, James A.; Dohm, James M.; Irwin, Rossman P.; Kolb, Eric J.; Fortezzo, Corey M.; Platz, Thomas; Michael, Gregory G.; Hare, Trent M.

    2014-01-01

    This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and interpretation in support of geologic mapping. In particular, the precise topographic mapping now available has enabled consistent morphologic portrayal of the surface for global mapping (whereas previously used visual-range image bases were less effective, because they combined morphologic and albedo information and, locally, atmospheric haze). Also, thermal infrared image bases used for this map tended to be less affected by atmospheric haze and thus are reliable for analysis of surface morphology and texture at even higher resolution than the topographic products.

  16. Geoconservation mapping using digital geomorphological maps in Vorarlberg, Austria

    Science.gov (United States)

    Seijmonsbergen, A. C.; De Jong, M. G. G.; de Graaff, L. W. S.; Anders, N. S.

    2012-04-01

    Geomorphological inventories are being made in the State of Vorarlberg (Austria) since the mid-1950s by the University of Amsterdam. Starting as an academic training fieldwork for undergraduate geomorphology students, PhD students and staff members soon recognized the research potential of the unique alpine landscape. In particular, landforms and deposits of the ice-marginal environment and pollen records preserved in peat provide valuable proxies for climate reconstruction and give detailed insight in the former growth and decay of the Rhine glacier network and of local glaciers, and assist in reconstructing landscape development in general. A project was started in 2007 to prepare community wide inventory maps of potential geoconservation areas, based on digital geomorphological mapping in a Geographical Information System (GIS). A stepwise protocol was designed for the identification of potential geoconservation areas in the landscape, comprising: 1. Preparing digital geomorphological maps, using a morphogenetic classification scheme 2. Assigning values for selected geoconservation assessment criteria to types of geomorphological features 3. Ranking the criteria assessment values into three categories of potential geoconservation value, and 4. Storing, visualizing and describing the geoconservation data. Four major traits are used in the weighting and ranking protocol (steps 2 and 3): scientific relevance, frequency of occurrence, disturbance, and environmental vulnerability. The process of assigning values and of ranking the landforms and deposits has been automated in GIS. For the evaluation of disturbance we use digital infrastructure layers in GIS which can be intersected with the potential geoconservation areas to determine the level of disturbance. The proposed method is demonstrated for the municipality of Lech, a well-known winter skiing resort. To illustrate the loss of high-rank potential geoconservation areas due to human influence over the last 50

  17. Seismic-hazard maps for the conterminous United States, 2014

    Science.gov (United States)

    Petersen, Mark D.; Moschetti, Morgan P.; Powers, Peter M.; Mueller, Charles S.; Haller, Kathleen M.; Frankel, Arthur D.; Zeng, Yuehua; Rezaeian, Sanaz; Harmsen, Stephen C.; Boyd, Oliver S.; Field, Edward H.; Chen, Rui; Luco, Nicolas; Wheeler, Russell L.; Williams, Robert A.; Olsen, Anna H.; Rukstales, Kenneth S.

    2015-01-01

    The maps presented here provide an update to the 2008 data contained in U.S Geological Survey Scientific Investigations Map 3195 (http://pubs.usgs.gov/sim/3195/).Probabilistic seismic-hazard maps were prepared for the conterminous United States for 2014 portraying peak horizontal acceleration and horizontal spectral response acceleration for 0.2- and 1.0-second periods with probabilities of exceedance of 10 percent in 50 years and 2 percent in 50 years. All of the maps were prepared by combining the hazard derived from spatially smoothed historical seismicity with the hazard from fault-specific sources. The acceleration values contoured are the random horizontal component. The reference site condition is firm rock, defined as having an average shear-wave velocity of 760 m/s in the top 30 meters corresponding to the boundary between NEHRP (National Earthquake Hazards Reduction program) site classes B and C.

  18. Groundwater vulnerability mapping in Guadalajara aquifers system (Western Mexico)

    Science.gov (United States)

    Rizo-Decelis, L. David; Marín, Ana I.; Andreo, Bartolomé

    2016-04-01

    Groundwater vulnerability mapping is a practical tool to implement strategies for land-use planning and sustainable socioeconomic development coherent with groundwater protection. The objective of vulnerability mapping is to identify the most vulnerable zones of catchment areas and to provide criteria for protecting the groundwater used for drinking water supply. The delineation of protection zones in fractured aquifers is a challenging task due to the heterogeneity and anisotropy of hydraulic conductivities, which makes difficult prediction of groundwater flow organization and flow velocities. Different methods of intrinsic groundwater vulnerability mapping were applied in the Atemajac-Toluquilla groundwater body, an aquifers system that covers around 1300 km2. The aquifer supplies the 30% of urban water resources of the metropolitan area of Guadalajara (Mexico), where over 4.6 million people reside. Study area is located in a complex neotectonic active volcanic region in the Santiago River Basin (Western Mexico), which influences the aquifer system underneath the city. Previous works have defined the flow dynamics and identified the origin of recharge. In addition, the mixture of fresh groundwater with hydrothermal and polluted waters have been estimated. Two main aquifers compose the multilayer system. The upper aquifer is unconfined and consists of sediments and pyroclastic materials. Recharge of this aquifer comes from rainwater and ascending vertical fluids from the lower aquifer. The lower aquifer consists of fractured basalts of Pliocene age. Formerly, the main water source has been the upper unit, which is a porous and unconsolidated unit, which acts as a semi-isotropic aquifer. Intense groundwater usage has resulted in lowering the water table in the upper aquifer. Therefore, the current groundwater extraction is carried out from the deeper aquifer and underlying bedrock units, where fracture flow predominates. Pollution indicators have been reported in

  19. Preparing for Multiple Births

    Science.gov (United States)

    ... Video Games, and the Internet Preparing for Multiple Births KidsHealth > For Parents > Preparing for Multiple Births Print ... a combination of both. The Risks of Multiple Births The most common risk involved with multiple births ...

  20. Mental Mapping: A Classroom Strategy

    Science.gov (United States)

    Solomon, Les

    1978-01-01

    Examines potential uses of mental maps in the classroom by reviewing research efforts, providing an example of the differences between mental maps of two student groups, and suggesting how to use mental maps in the geography curriculum. Mental mapping (or cognitive mapping) refers to individuals' processes of collecting, storing, and retrieving…

  1. Thesis Preparation Manual

    OpenAIRE

    1999-01-01

    "This Thesis Preparation Manual has been written to provide you with format and procedure guidance for preparing and processing your thesis at the Naval Postgraduate School. It covers both unclassified and classified theses. All theses and thesis technical reports must be prepared in accordance with these guidelines. Please note that this manual is not written in the thesis format." form the Foreword

  2. nowCOAST's Map Service for Transportation Map Overlays

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Map Information: This nowCOAST map service provides maps depicting the locations of major world airport runways, major U.S. seaports, and latitude/longitude grid...

  3. nowCOAST's Map Service for Political Map Overlays

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Map Information: This nowCOAST map service provides map overlays depicting the boundaries of U.S. states, territories, counties and townships/county subdivisions,...

  4. Volcanic Hazard Maps; the results and progress made by the IAVCEI Hazard Map working group

    Science.gov (United States)

    Calder, Eliza; Lindsay, Jan; Wright, Heather

    2017-04-01

    The IAVCEI Commission on Volcanic Hazards and Risk set up a working group on Hazard Maps in 2014. Since then, the group has led or co-organised three major workshops, and organized two thematic conference sessions. In particular we have initiated a series of workshops, named the "State of the Hazard Map" which we plan to continue (the first was held at COV8 (State of the Hazard Map 1) and second at COV9 (State of the Hazard Map 2) and the third will be held at IAVCEI General Assembly in Portland. The broad aim of these activities is to work towards an IAVCEI-endorsed considerations or guidelines document for volcanic hazard map generation. The workshops have brought together people from around the world working on volcanic hazard maps, and have had four primary objectives: 1) to review (and collect further data on) the diverse variety of methods and rationales currently used to develop maps; 2) to openly discuss approaches and experiences regarding how hazard maps are interpreted and used by different groups; 3) to discuss and prepare the IAVCEI Guidelines document; and lastly, 4) Discuss options for finalizing, publishing and disseminating the Guidelines document (e.g. wiki, report, open-source publication). This presentation will provide an update of the results and outcomes of those initiatives. This includes brief outcomes of the reviews undertaken, a survey that has been constructed in order to gather additional data, the planned structure for the guidelines documents and a summary of the key findings to date. The majority of the participants of these activities so far have come from volcano observatories or geological surveys, as these institutions commonly have primary responsibility for making operational hazard map. It is important however that others in the scientific community that work on quantification of volcanic hazard contribute to these guidelines. We therefore invite interested parties to become involved.

  5. Preliminary heat flow map of Europe. Explanatory text

    Energy Technology Data Exchange (ETDEWEB)

    Cermak, V.; Hurtig, E.

    1977-08-08

    A preliminary heat flow map of Europe was prepared, based on data contained in 401 references. The map was prepared on a scale of 1:5,000,000 and shows broad-scale geological structure (e.g., platforms, shields, foredeeps) and specialized rock suites (ophiolites, volcanites). Primary faults and thrust faults are indicated, and contours showing the depth of crystalline basement are given. Heat flow is plotted using 10.0 mW/m/sup 2/ isotherms. The accompanying explanatory text describes data acquisition and techniques of correction, and discusses some implications of the results.

  6. Fractional standard map

    Energy Technology Data Exchange (ETDEWEB)

    Edelman, Mark, E-mail: edelman@cims.nyu.ed [Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 (United States)] [Department of Physics, Stern College at Yeshiva University, 245 Lexington Avenue, New York, NY 10016 (United States); Tarasov, Vasily E. [Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 (United States)] [Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow 119991 (Russian Federation)

    2009-12-28

    Properties of the phase space of the standard map with memory are investigated. This map was obtained from a kicked fractional differential equation. Depending on the value of the map parameter and the fractional order of the derivative in the original differential equation, this nonlinear dynamical system demonstrates attractors (fixed points, stable periodic trajectories, slow converging and slow diverging trajectories, ballistic trajectories, and fractal-like structures) and/or chaotic trajectories. At least one type of fractal-like sticky attractors in the chaotic sea was observed.

  7. Map: Geospatial paradigm

    Directory of Open Access Journals (Sweden)

    Ikonović Vesna

    2006-01-01

    Full Text Available There are different definitions of map. There is no one which is accepted in whole world or at least from the most cartographers. In the paper it will be given several definitions which are, at the best way, (according to the author’s opinion reflecting essence of map as a model of reality. Map as a universal meaning of researching can’t serve only for representing particular geospace (spatial system or some its element, or to give only clear view about geographical dispersion of objects, phenomena and processes, but have to make possible studying the patterns of that dispersion, as well as their mutual connections and conditions.

  8. The Problem of Map Illiteracy.

    Science.gov (United States)

    Ryan, James D.

    1985-01-01

    Describes an approach to eliminating "map illiteracy" in college students. Map illiteracy is defined as the inability to read and draw meaning from simple maps used in history texts and teaching. (JDH)

  9. Tools for mapping ecosystem services

    Science.gov (United States)

    Palomo, Ignacio; Adamescu, Mihai; Bagstad, Kenneth J.; Cazacu, Constantin; Klug, Hermann; Nedkov, Stoyan; Burkhard, Benjamin; Maes, Joachim

    2017-01-01

    Mapping tools have evolved impressively in recent decades. From early computerised mapping techniques to current cloud-based mapping approaches, we have witnessed a technological evolution that has facilitated the democratisation of Geographic Information

  10. Northern Hemisphere Synoptic Weather Maps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily Series of Synoptic Weather Maps. Part I consists of plotted and analyzed daily maps of sea-level and 500-mb maps for 0300, 0400, 1200, 1230, 1300, and 1500...

  11. International perspectives on coal preparation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The report consists of the vugraphs from the presentations which covered the following topics: Summaries of the US Department of Energy`s coal preparation research programs; Preparation trends in Russia; South African coal preparation developments; Trends in hard coal preparation in Germany; Application of coal preparation technology to oil sands extraction; Developments in coal preparation in China; and Coal preparation in Australia.

  12. The CHUVA Lightning Mapping Campaign

    Science.gov (United States)

    Goodman, Steven J.; Blakeslee, Richard J.; Bailey, Jeffrey C.; Carey, Lawrence D.; Hoeller, Hartmut; Albrecht, Rachel I.; Morales, Carlos; Pinto, Osmar; Saba, Marcelo M.; Naccarato, Kleber; Hembury, Nikki; Nag, Amitabh; Heckman, Stan; Holzworth, Robert H.; Rudlosky, Scott D.; Betz, Hans-Dieter; Said, Ryan; Rauenzahn, Kim

    2011-01-01

    The primary science objective for the CHUVA lightning mapping campaign is to combine measurements of total lightning activity, lightning channel mapping, and detailed information on the locations of cloud charge regions of thunderstorms with the planned observations of the CHUVA (Cloud processes of tHe main precipitation systems in Brazil: A contribUtion to cloud resolVing modeling and to the GPM (GlobAl Precipitation Measurement) field campaign. The lightning campaign takes place during the CHUVA intensive observation period October-December 2011 in the vicinity of S o Luiz do Paraitinga with Brazilian, US, and European government, university and industry participants. Total lightning measurements that can be provided by ground-based regional 2-D and 3-D total lightning mapping networks coincident with overpasses of the Tropical Rainfall Measuring Mission Lightning Imaging Sensor (LIS) and the SEVIRI (Spinning Enhanced Visible and Infrared Imager) on the Meteosat Second Generation satellite in geostationary earth orbit will be used to generate proxy data sets for the next generation US and European geostationary satellites. Proxy data, which play an important role in the pre-launch mission development and in user readiness preparation, are used to develop and validate algorithms so that they will be ready for operational use quickly following the planned launch of the GOES-R Geostationary Lightning Mapper (GLM) in 2015 and the Meteosat Third Generation Lightning Imager (LI) in 2017. To date there is no well-characterized total lightning data set coincident with the imagers. Therefore, to take the greatest advantage of this opportunity to collect detailed and comprehensive total lightning data sets, test and validate multi-sensor nowcasting applications for the monitoring, tracking, warning, and prediction of severe and high impact weather, and to advance our knowledge of thunderstorm physics, extensive measurements from lightning mapping networks will be collected

  13. Mapping of Nature Risks and Disasters for Educational Purposes

    Directory of Open Access Journals (Sweden)

    Temenoujka Bandrova

    2006-12-01

    Full Text Available The paper presents definitions of nature risks and disasters. Mapping of risk processes is discussed in the direction of educational purposes. International organizations publish information brochures about how to teach children correct behaviour and preparation for natural disasters. Questions such as "What do you do in case of an emergency" are discussed. Standards and technologies related to emergency management are considered. Some examples of maps and methods of mapping for young and older students are presented, and a proposal for the National Strategy in the field of education is created on the basis of them.Ključne riječi 

  14. Construction of Genetic Linkage Map of Bread Wheat (Triticum aestivum L.) Using an Intervarietal Cross and QTL Map for Spike Related Traits

    Institute of Scientific and Technical Information of China (English)

    E. Nalini; S.G. Bhagwat; N. Jawali

    2007-01-01

    @@ Most often a genetic linkage map is prepared using populations obtained from two highly diverse genotypes.However, the markers from such a map may not be useful in a breeding program as these markers may not be polymorphie among the varieties used in breeding.

  15. Mapping posthumanism: an exchange

    OpenAIRE

    2004-01-01

    Introduction: posthumanism in question Noel Castree, Catherine Nash Mapping posthumanism Neil Badmington Modalities of posthumanism Bruce Braun Humanising posthumanism Jonathan Murdoch Humanism's excess: some thoughts on the 'post-human/ist' agenda Sarah Whatmore Organisors: Noel Castree, Catherine Nash

  16. FLOODPLAIN MAPPING, Bandera, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  17. PDS Planetary Maps API

    Data.gov (United States)

    National Aeronautics and Space Administration — We are developing a set of NASA Extensions to the Google Maps API—and soon to other frameworks such as OpenLayers as well—that will make these platforms more useful...

  18. Haz-Map

    Data.gov (United States)

    U.S. Department of Health & Human Services — Haz-Map is an occupational health database designed for health and safety professionals and for consumers seeking information about the adverse effects of workplace...

  19. MAPPING IN MICRONESIA.

    Science.gov (United States)

    Olsen, Randle W.; Swinnerton, J.R.

    1984-01-01

    The U. S. Geological Survey has recently completed a series of new topographic maps of Micronesia in cooperation with the Trust Territory of the Pacific Islands, the Federal agency administering the islands. Monocolor 1:10,000-scale manuscripts were compiled, from which 1:25,000-scale metric quadrangles were derived with symbology consistent with USGS quadrangle mapping. The publication of these new maps coincides with the impending political changes resulting from self-determination referendums held in Micronesia. Local sources have helped considerably with field logistics and resolution of geographic name controversies. Technical aspects of this project included development of tropical feature symbology, location of cadastral subdivisions and associated boundaries and mapping of many outlying coral reefs.

  20. Public Waters Inventory Maps

    Data.gov (United States)

    Minnesota Department of Natural Resources — This theme is a scanned and rectified version of the Minnesota DNR - Division of Waters "Public Waters Inventory" (PWI) maps. DNR Waters utilizes a small scale...

  1. Map of physics

    Science.gov (United States)

    2008-10-01

    Based on bibliometric data from information-services provider Thomson Reuters, this map reveals "core areas" of physics, shown as coloured circular nodes, and the relationship between these subdisciplines, shown as lines.

  2. Mapping the EEZ

    Digital Repository Service at National Institute of Oceanography (India)

    De, S.; Shashikumar, K.

    Mariana. Countries like Australia, Brazil, Chile, China, Ireland, New Zealand, Pakistan, Sweden and Venezuela are all actively running programs on EEZ surveys. Mapping the Oceans Assessment of EEZ resources requires comprehensive, accurate, and up...

  3. National Coastal Mapping Program

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — The U. S. Army Corps of Engineers (USACE) National Coastal Mapping Program (NCMP) is designed to provide high-resolution elevation and imagery data along U.S....

  4. The CPD Maps System

    Data.gov (United States)

    Department of Housing and Urban Development — CPD Maps includes data on the locations of existing CDBG, HOME, public housing and other HUD-funded community assets, so that users can view past investments...

  5. Daily Weather Maps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Several different government offices have published the Daily weather maps over its history. The publication has also gone by different names over time. The U.S....

  6. Formal genetic maps

    African Journals Online (AJOL)

    Mohammad Saad Zaghloul Salem

    2014-12-24

    Dec 24, 2014 ... Abstract Formal genetic maps are databases, represented as text or graphic figures, that can be ..... cantly, to our current vague and scanty knowledge of many, ...... similar to reverse engineering techniques, might be worthy of.

  7. TOXMAP®: Environmental Health Maps

    Data.gov (United States)

    U.S. Department of Health & Human Services — TOXMAP® is a Geographic Information System (GIS) that uses maps of the United States and Canada to help users visually explore data primarily from the EPA's Toxics...

  8. Minidoka - Invasive Species Mapping

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Locate and map, via the use of GPS, Rush skeletonweed on the refuge. Located areas then entered into GIS to allow refuge staff to pin point locations and treat this...

  9. Programming with Hierarchical Maps

    DEFF Research Database (Denmark)

    Ørbæk, Peter

    This report desribes the hierarchical maps used as a central data structure in the Corundum framework. We describe its most prominent features, ague for its usefulness and briefly describe some of the software prototypes implemented using the technology....

  10. NOS Bathymetric Maps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection of bathymetric contour maps which represent the seafloor topography includes over 400 individual titles and covers US offshore areas including Hawaii...

  11. Marketplace Enrollment Maps

    Data.gov (United States)

    U.S. Department of Health & Human Services — The maps show the distribution of consumers in a state who enrolled in marketplace plans through federally facilitated, partnership, and supported state-based...

  12. FLOODPLAIN MAPPING, Atascosa, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  13. Coupled analytic maps

    CERN Document Server

    Bricmont, J; Bricmont J; Kupiainen A

    1994-01-01

    We consider a lattice of weakly coupled expanding circle maps. We construct, via a cluster expansion of the Perron-Frobenius operator, an invariant measure for these infinite dimensional dynamical systems which exhibits space-time-chaos.

  14. USGS map quadrangles

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — USGS map quandrangle boundaries with names and unique identifiers for the 1:24,000 (7.5 minute) quadrangles. Additional attributes provide unique identifiers and...

  15. BaseMap

    Data.gov (United States)

    California Department of Resources — The goal of this project is to provide a convenient base map that can be used as a starting point for CA projects. It's simple, but designed to work at a number of...

  16. Mapping Unknown Knowns

    DEFF Research Database (Denmark)

    Diogo de Andrade Silva, Elisa; Lanng, Ditte Bendix; Wind, Simon

    representative dimensions of travellers’ embodied ‘dwelling-in-motion’ (Urry, 2007) and experiences. The paper foregrounds a ‘Mapping-in-Motion’ graphic example, an experimental urban design student assignment aiming to map some of the less representative dimensions of journeys between A and B in Berlin......Mapping is often known as the entangled method of recognizing, representing and examining the existing physical conditions of a design site. Therefore, it becomes an evocative requirement to urban designers’ work in order to develop design proposals (Corner 1999). In this paper, we focus on mapping...... in relation to analysis, representation, exploration and design of everyday travelling in the city. Such ‘mobilities design’ (Jensen and Lanng 2017) concerns routes, sites and artefacts of mobilities, e.g., road networks, train stations, and bike parking facilities. Some dimensions of these structures...

  17. MetaMap

    Data.gov (United States)

    U.S. Department of Health & Human Services — MetaMap is a highly configurable application developed by the Lister Hill National Center for Biomedical Communications at the National Library of Medicine (NLM) to...

  18. Minimal measurements of the gate fidelity of a qudit map

    CERN Document Server

    Bagán, E; Muñoz-Tàpia, R

    2003-01-01

    We obtain a simple formula for the average gate fidelity of a linear map acting on qudits. It is given in terms of minimal sets of pure state preparations alone, which may be interesting from the experimental point of view. These preparations can be seen as the outcomes of certain minimal positive operator valued measures. The connection of our results with these generalized measurements is briefly discussed.

  19. Complete Quasiconvex Mappings in Polydisc

    Institute of Scientific and Technical Information of China (English)

    LIU Tai-shun; ZHANG Wen-jun

    2006-01-01

    In this paper,a class of biholomorphic mappings called complete quasiconvex mappings is introduced and studied in bounded convex Reinhardt domains of Cn.Through a detailed analysis of the analytic characterization for this class of mappings,it is shown that this class of mappings contains the convex mappings and is also a subset of the class of starlike mappings.In the special case of the polydisc,a decomposition theorem is established for the complete quasiconvex mappings,which in turn is used to derive an improved sufficient condition for the convex mappings.

  20. Correlation of physical and genetic maps of human chromosome 16

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, G.R.

    1991-01-01

    This project aimed to divide chromosome 16 into approximately 50 intervals of {approximately}2Mb in size by constructing a series of mouse/human somatic cell hybrids each containing a rearranged chromosome 16. Using these hybrids, DNA probes would be regionally mapped by Southern blot or PCR analysis. Preference would be given to mapping probes which demonstrated polymorphisms for which the CEPH panel of families had been typed. This would allow a correlation of the physical and linkage maps of this chromosome. The aims have been substantially achieved. 49 somatic cell hybrids have been constructed which have allowed definition of 46, and potentially 57, different physical intervals on the chromosome. 164 loci have been fully mapped into these intervals. A correlation of the physical and genetic maps of the chromosome is in an advanced stage of preparation. The somatic cell hybrids constructed have been widely distributed to groups working on chromosome 16 and other genome projects.

  1. A process-based 222Rn flux map for Europe and its comparison to long-term observations

    Directory of Open Access Journals (Sweden)

    U. Karstens

    2015-06-01

    Full Text Available Detailed 222Rn flux maps are an essential prerequisite for the use of radon in atmospheric transport studies. Here we present a high-resolution222Rn flux map for Europe, based on a parameterization of 222Rn production and transport in the soil. The 222Rn exhalation rate was parameterized based on soil properties, uranium content, and modelled soil moisture from two different land-surface reanalysis data sets. Spatial variations in exhalation rates are primarily determined by the uranium content of the soil, but also influenced by local water table depth and soil texture. Temporal variations are related to soil moisture variations as the molecular diffusion in the unsaturated soil zone depends on available air-filled pore space. The implemented diffusion parameterization was tested against campaign-based 222Rn profile measurements. Monthly 222Rn exhalation rates from European soils were calculated with a nominal spatial resolution of 0.083° × 0.083° and compared to long-term direct measurements of 222Rn exhalation rates in different areas of Europe. The two realizations of the 222Rn flux map, based on the different soil moisture data sets, both realistically reproduce the observed seasonality in the fluxes but yield considerable differences for absolute flux values. The average 222Rn flux from soils in Europe is estimated to be 10 or 15 mBq m-2 s-1, depending on the soil moisture data set, and the seasonal variations in the two realisations range from 7.1 mBq m-2 s-1 in February to 13.9 mBq m-2 s-1 in August and from 10.8 mBq m-2 s-1 in March to 19.7 mBq m-2 s-1 in July, respectively. This systematic difference highlights the importance of realistic soil moisture data for a reliable estimation of 222Rn exhalation rates.

  2. Electrophoretic High Molecular Weight DNA Purification Enables Optical Mapping

    Science.gov (United States)

    Maydan, Jason; Thomas, Matthew; Tabanfar, Leyla; Mai, Laura; Poon, Hau-Ling; Pe, Joel; Hahn, Kristen; Goji, Noriko; Amoako, Kingsley; Marziali, Andre; Hanson, Dan

    2013-01-01

    Optical mapping generates an ordered restriction map from single, long DNA molecules. By overlapping restriction maps from multiple molecules, a physical map of entire chromosomes and genomes is constructed, greatly facilitating genome assembly in next generation sequencing projects, comparative genomics and strain typing. However, optical mapping relies on a method of preparing high quality DNA >250 kb in length, which can be challenging from some organisms and sample types. Here we demonstrate the ability of Boreal Genomics' Aurora instrument to provide pure, high molecular weight (HMW) DNA 250-1,100 kb in length, ideally suited for optical mapping. The Aurora performs electrophoretic DNA purification within an agarose gel in reusable cartridges, protecting long DNA molecules from shearing forces associated with liquid handling steps common to other purification methods. DNA can be purified directly from intact cells embedded and lysed within an agarose gel, preserving the highest molecular weight DNA possible while achieving exceptional levels of purity. The Aurora delivers DNA in a buffer solution, where DNA can be condensed and protected from shearing during recovery with a pipette. DNA is then returned to its regular coiled state by simple dilution prior to optical mapping. Here we present images showing HMW DNA purification taking place in the Aurora and subsequent images of single DNA molecules on OpGen's Argus® Optical Mapping System. Future work will focus on further optimizing Aurora HMW DNA purification to bias DNA recovery in favor of only the longest molecules in a sample, maximizing the benefits of optical mapping.

  3. Olympic Maps Available

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Beijing is publishing a set of Olympic maps covering everything from the location of sporting venues to the city’s history As soon as Zhou Liyi hopped off the train from Shanghai to Beijing, he hurried to Wangfujing Xinhua Book Store,one of the largest of its kind in Beijing,to buy an Olympic map. Zhou is a Shanghai resident who came to Beijing on business and plans to return as a

  4. Maps and (no) Simulations

    Science.gov (United States)

    Forest, Etienne

    As the title suggests, I examine the role of maps in accelerator theory, conveniently leaving simulation out of the picture for lack of time and space. This is really a primer on the map-based "Courant Snyder" theory as independently proposed by Dragt's group (author included) and Turchetti's group at Bologna. Quite obviously it is viewed here from the author's own perspective and prejudices.

  5. Wind Resource Maps (Postcard)

    Energy Technology Data Exchange (ETDEWEB)

    2011-07-01

    The U.S. Department of Energy's Wind Powering America initiative provides high-resolution wind maps and estimates of the wind resource potential that would be possible from development of the available windy land areas after excluding areas unlikely to be developed. This postcard is a marketing piece that stakeholders can provide to interested parties; it will guide them to Wind Powering America's online wind energy resource maps.

  6. Irreversible quantum baker map.

    Science.gov (United States)

    Łoziński, Artur; Pakoński, Prot; Zyczkowski, Karol

    2002-12-01

    We propose a generalization of the model of classical baker map on the torus, in which the images of two parts of the phase space do overlap. This transformation is irreversible and cannot be quantized by means of a unitary Floquet operator. A corresponding quantum system is constructed as a completely positive map acting in the space of density matrices. We investigate spectral properties of this superoperator and their link with the increase of the entropy of initially pure states.

  7. Irreversible Quantum Baker Map

    CERN Document Server

    Lozinski, A; Zyczkowski, K; Lozinski, Artur; Pakonski, Prot; Zyczkowski, Karol

    2002-01-01

    We propose a generalization of the model of classical baker map on the torus, in which the images of two parts of the phase space do overlap. This transformation is irreversible and cannot be quantized by means of a unitary Floquet operator. A corresponding quantum system is constructed as a completely positive map acting in the space of density matrices. We investigate spectral properties of this super-operator and their link with the increase of the entropy of initially pure states.

  8. Creating Heliophysics Concept Maps

    Science.gov (United States)

    Ali, N. A.; Peticolas, L. M.; Paglierani, R.; Mendez, B. J.

    2011-12-01

    The Center for Science Education at University of California Berkeley's Space Sciences Laboratory is creating concept maps for Heliophysics and would like to get input from scientists. The purpose of this effort is to identify key concepts related to Heliophysics and map their progression to show how students' understanding of Heliophysics might develop from Kindergarten through higher education. These maps are meant to tie into the AAAS Project 2061 Benchmarks for Scientific Literacy and National Science Education Standards. It is hoped that the results of this effort will be useful for curriculum designers developing Heliophysics-related curriculum materials and classroom teachers using Heliophysics materials. The need for concept maps was identified as a result of product analysis undertaken by the NASA Heliophysics Forum Team. The NASA Science Education and Public Outreach Forums have as two of their goals to improve the characterization of the contents of the Science Mission Directorate and Public Outreach (SMD E/PO) portfolio (Objective 2.1) and assist SMD in addressing gaps in the portfolio of SMD E/PO products and project activities (Objective 2.2). An important part of this effort is receiving feedback from solar scientists regarding the inclusion of key concepts and their progression in the maps. This session will introduce the draft concept maps and elicit feedback from scientists.

  9. Mars synthetic topographic mapping

    Science.gov (United States)

    Wu, S.S.C.

    1978-01-01

    Topographic contour maps of Mars are compiled by the synthesis of data acquired from various scientific experiments of the Mariner 9 mission, including S-band radio-occulation, the ultraviolet spectrometer (UVS), the infrared radiometer (IRR), the infrared interferometer spectrometer (IRIS) and television imagery, as well as Earth-based radar information collected at Goldstone, Haystack, and Arecibo Observatories. The entire planet is mapped at scales of 1:25,000,000 and 1:25,000,000 using Mercator, Lambert, and polar stereographic map projections. For the computation of map projections, a biaxial spheroid figure is adopted. The semimajor and semiminor axes are 3393.4 and 3375.7 km, respectively, with a polar flattening of 0.0052. For the computation of elevations, a topographic datum is defined by a gravity field described in terms of spherical harmonics of fourth order and fourth degree combined with a 6.1-mbar occulation pressure surface. This areoid can be approximated by a triaxial ellipsoid with semimajor axes of A = 3394.6 km and B = 3393.3 km and a semiminor axis of C = 3376.3 km. The semimajor axis A intersects the Martian surface at longitude 105??W. The dynamic flattening of Mars is 0.00525. The contour intercal of the maps is 1 km. For some prominent features where overlapping pictures from Mariner 9 are available, local contour maps at relatively larger scales were also compiled by photogrammetric methods on stereo plotters. ?? 1978.

  10. Landslide inventory maps: New tools for an old problem

    Science.gov (United States)

    Guzzetti, Fausto; Mondini, Alessandro Cesare; Cardinali, Mauro; Fiorucci, Federica; Santangelo, Michele; Chang, Kang-Tsung

    2012-04-01

    Landslides are present in all continents, and play an important role in the evolution of landscapes. They also represent a serious hazard in many areas of the world. Despite their importance, we estimate that landslide maps cover less than 1% of the slopes in the landmasses, and systematic information on the type, abundance, and distribution of landslides is lacking. Preparing landslide maps is important to document the extent of landslide phenomena in a region, to investigate the distribution, types, pattern, recurrence and statistics of slope failures, to determine landslide susceptibility, hazard, vulnerability and risk, and to study the evolution of landscapes dominated by mass-wasting processes. Conventional methods for the production of landslide maps rely chiefly on the visual interpretation of stereoscopic aerial photography, aided by field surveys. These methods are time consuming and resource intensive. New and emerging techniques based on satellite, airborne, and terrestrial remote sensing technologies, promise to facilitate the production of landslide maps, reducing the time and resources required for their compilation and systematic update. In this work, we first outline the principles for landslide mapping, and we review the conventional methods for the preparation of landslide maps, including geomorphological, event, seasonal, and multi-temporal inventories. Next, we examine recent and new technologies for landslide mapping, considering (i) the exploitation of very-high resolution digital elevation models to analyze surface morphology, (ii) the visual interpretation and semi-automatic analysis of different types of satellite images, including panchromatic, multispectral, and synthetic aperture radar images, and (iii) tools that facilitate landslide field mapping. Next, we discuss the advantages and the limitations of the new remote sensing data and technology for the production of geomorphological, event, seasonal, and multi-temporal inventory maps

  11. The NASA/USGS Planetary Geologic Mapping Program

    Science.gov (United States)

    Tanaka, K.

    NASA's Planetary Geologic Mapping Program (PGM) publishes geologic maps of the planets based on released, geodetically controlled spacecraft data. The general objectives of PGM include (1) production of geologic maps that will greatly increase our knowledge of the materials and processes that have contributed to the evolution of Solar System bodies, and (2) geologic surveys of areas of special interest that may be investigated by future missions. Although most map authors are from U.S. institutions, some European investigators have also served as authors. PGM is sponsored by NASA's Planetary Geology and Geophysics Program (PGG) and has been supported by personnel of the Astrogeology Team of the U.S. Geological Survey (USGS) for more than 40 years. PGG also supports the Astrogeology Team to prepare and distribute controlled data products necessary for the production of geologic maps. USGS coordination and outreach activities for PGM include developing new planetary geologic map series, managing existing map series, generating geologic mapping databases and packages for individual mapping investigators, providing oversight and expertise in meeting the requirements of USGS map standards, providing editorial support in map reviews and revisions, supporting map pre-press production, and maintaining an informative planetary geologic mapping web page (http://astrogeology.usgs.gov/Projects/PlanetaryMapping/). The Astrogeology Team also provides a Geographic Information Systems (GIS) web site (Planetary Interactive GIS on the Web Analyzable Database, or PIGWAD) to facilitate distribution and analysis of spatially registered, planetary geologic data primarily in vector form. USGS now publishes planetary geologic map data in GIS format. Geologic maps of planetary bodies published by USGS through 2005 include 80 of the Moon from 1:10K to 1:5M scale, 93 of Mars from 1:500K to 1:15M scale, 18 of Venus at 1:5M and 1:15M scales, 9 of Mercury at 1:5M scale, and 16 of the Galilean

  12. Development of base maps' role in soil mapping

    Science.gov (United States)

    Miller, Brad; Brevik, Eric

    2014-05-01

    One of the ultimate goals of soil science is the production of accurate soil maps, but historically these thematic maps have relied upon base maps for positional reference and later for parameters that help predict soil properties. This presentation reviews the history of base maps and the dependence of soil mapping on them. The availability of geographic technology for producing these base maps has constrained and directed the geographic study of soil. A lack of accurate methods for determining location limited early geographic description of soils to narratives. The availability of accurate topographic maps in the late 18th century, fueled by governments' interests in documenting national boundaries and popular interest in world atlases, provided the first base maps for soil geographers. These soil maps primarily used the topographic maps as a spatial reference onto which the thematic details were drawn. Due to the late start of a systematic topographic survey in the United States, early Soil Survey maps depended upon plat maps for spatial reference. The adoption of aerial photographs in the process of soil mapping increased the role of base maps as predictive parameters. In the current geospatial revolution, global positioning systems and geographic information systems have nearly replaced the need for base maps to provide spatial reference. Today, base maps are more likely to be used as parameters in landscape models for predicting the spatial distribution of soil properties and classes. As model parameters for digital soil maps, base maps constitute the library of predictive variables and constrain the supported resolution of the soil map. This change in the relationship between base maps and the soil map is a paradigm shift that affects fundamental definitions of geography, such as scale, resolution, and detectable features. These concepts are the essential tools used to study the spatial characteristics of Earth Systems.

  13. Conformal mappings and CR mappings on the Engel group

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    We show that conformal mappings between the Engel groups are CR or anti-CR mappings. This reduces the determination of conformal mappings to a problem in the theory of several complex analysis.The result about the group of CR automorphisms is used to determine the identity component of the group of conformal mappings on the Engel group.

  14. Conformal mappings and CR mappings on the Engel group

    Institute of Scientific and Technical Information of China (English)

    WU QingYan; WANG Wei

    2009-01-01

    We show that conformal mappings between the Engel groups are CR or anti-CR mappings.This reduces the determination of conformal mappings to a problem in the theory of several complex analysis. The result about the group of CR automorphisms is used to determine the identity component of the group of conformal mappings on the Engel group.

  15. Geologic Mapping of Vesta

    Science.gov (United States)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-01-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High- Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were

  16. Geologic mapping of Vesta

    Science.gov (United States)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-11-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High-Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were

  17. Geologic Map of the Thaumasia Region, Mars

    Science.gov (United States)

    Dohm, Janes M.; Tanaka, Kenneth L.; Hare, Trent M.

    2001-01-01

    ). The medium-resolution Viking images used for mapping and base preparation also formed the basis of the 1:2,000,000 scale subquadrangle series. Earlier geologic maps of all or parts of the region include: (1) maps of the Phoenicis Lacus, Coprates, Thaumasia, and Argyre quadrangles at 1:5,000,000 scale based mainly on Mariner 9 images (respectively, Masursky and others, 1978; McCauley, 1978; McGill, 1978; and Hodges, 1980), (2) the global map of Mars at 1:25,000,000 (Scott and Carr, 1978) compiled largely from the 1:5,000,000 scale geologic maps, (3) maps showing lava flows in the Tharsis region at 1:2,000,000 scale compiled from Viking and Mariner 9 images (Scott, 1981; Scott and Tanaka, 1981a, b; Scott and others, 1981), (4) the map of the western equatorial region of Mars at 1:15,000,000 scale based on Viking images (Scott and Tanaka, 1986), and (5) the map of the Valles Marineris region at 1:2,000,000 scale compiled from Viking images (Witbeck and others, 1991). The previous maps have described the overall geology and geomorphology of the region but have not unraveled the detailed stratigraphy and complex evolution of this unique and geologically diverse martian province. The main purpose of this comprehensive mapping project is to reconstruct the stratigraphic, structural, and erosional histories of the Thaumasia region. The region is the last major province of the Tharsis region to undergo detailed structural mapping using Viking images; its history is essential to documenting the overall tectonic history of Tharsis. Other provinces of Tharsis that have been structurally mapped include Syria Planum (Tanaka and Davis, 1988), Tempe Terra and Ulysses Patera (Scott and Dohm, 1990b), and Alba Patera (Tanaka, 1990). Another primary mapping objective is to determine the region's volcanic history and assess the relations among fault systems and volcanoes (Wise and others, 1979; Scott and Tanaka, 1980; Whitford-Stark, 1982; Scott and Dohm, 1990a). A secondary mapping

  18. [Aesthetic surgery, psychic preparation].

    Science.gov (United States)

    Feiss, R

    2003-10-01

    The aesthetic surgery impacts the psychological picture of the body. The candidate must be prepared to this change in appearance. If not, the surgeon must suggest the psychological preparation, evaluating the risk of dissatisfaction, in order to allow the surgical and narcissistic success of his operation. The author, a psychiatric, beneficiary in a strong experience of a surgical assistance, develops the interest of such a preparation upon a period of about 15 years (1988-2002).

  19. An approach to reduce mapping errors in the production of landslide inventory maps

    Directory of Open Access Journals (Sweden)

    M. Santangelo

    2015-07-01

    Full Text Available Landslide inventory maps (LIMs show where landslides have occurred in an area, and provide information useful to different types of landslide studies, including susceptibility and hazard modelling and validation, risk assessment, erosion analyses, and to evaluate relationships between landslides and geological settings. Despite recent technological advancements, visual interpretation of aerial photographs (API remains the most common method to prepare LIMs. In this work, we present a new semi-automatic procedure that exploits GIS technology for the digitalization of landslide data obtained through API. To test the procedure, and to compare it to a consolidated landslide mapping method, we prepared two LIMs starting from the same set of landslide API data, which were digitalized (a manually adopting a consolidated visual transfer method, and (b adopting our new semi-automatic procedure. Results indicate that the new semi-automatic procedure is more efficient and results in a more accurate LIM. With the new procedure, the landslide positional error decreases with increasing landslide size following a power-law. We expect that our work will help adopt standards for transferring landslide information from the aerial photographs to a digital landslide map, contributing to the production of accurate landslide maps.

  20. Materials Preparation Center

    Data.gov (United States)

    Federal Laboratory Consortium — MPC is recognized throughout the worldwide research community for its unique capabilities in purification, preparation, and characterization of: rare earth metals,...

  1. Materials Preparation Center

    Data.gov (United States)

    Federal Laboratory Consortium — MPC is recognized throughout the worldwide research community for its unique capabilities in purification, preparation, and characterization of: rare earth metals,...

  2. FLUORESCENCE OVERLAY ANTIGEN MAPPING OF THE EPIDERMAL BASEMENT-MEMBRANE ZONE .2. COLOR FIDELITY

    NARCIS (Netherlands)

    BRUINS, S; DEJONG, MCJM; HEERES, K; WILKINSON, MHF; JONKMAN, MF; VANDERMEER, JB

    In this second report on the fluorescence overlay antigen mapping (FOAM) technique, we highlight some of the errors that may influence faithful color rendition of slide preparations using triple antigen immunofluorescence staining. Reliable interpretation of multicolor fluorescence images requires

  3. Landsat-facilitated vegetation map and vegetation reconnaissance of Tetlin National Wildlife Refuge, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A Landsat assisted vegetation map was prepared for Tetlin National Wildlife Refuge (925,000 acres). The refuge lies within the northern boreal subzone of eastern...

  4. Detailed geomorphological map sheet Bela Palanka at scale 1:100,000

    Directory of Open Access Journals (Sweden)

    Menković Ljubomir

    2011-01-01

    Full Text Available The Geomorphological Map Sheet Bela Palanka is a graphical representation of landforms in the area covered by the Topographical Map Sheet Bela Palanka at scale 1:100,000. The map is published in 2008 by the Serbian Academy of Sciences and Arts (SASA and the SASA Geodynamics Board. It is the first detailed geomorphological map edited in Serbia. This paper presents the methods used in preparing the geomorphological map, the contents and the mode of data presentation, geologic structure, genetic types of landforms and the subtypes, and the geomorphological history since the Neogene.

  5. Islands Iž and Rava on Old Maps

    Directory of Open Access Journals (Sweden)

    Josip Faričić

    2014-06-01

    Full Text Available Exhibition Pax Anamarija, G&V Line Jadera, Zadar – Iž – Rava, 16–26 May 2014 The National Museum Zadar (Cultural-historical collection of the Island of Iž and the University of Zadar prepared the exhibition Islands Iž and Rava on Old Maps on the occasion of the International Museum Day. The exhibition was set on a passenger ship Anamarija owned by company G &V Line Jadera which connects islands Iž and Rava with Zadar. Visitors, mostly passengers on that route and on the Zadar – Sali – Zadar route with the same ship could see the exhibition from May 16 to 26, 2014. Considering that 200 small catalogues were printed containing an introduction and a list of exhibits and that more catalogues had to be printed, it can be assumed that the exhibition of old maps was very interesting to inhabitants of Iž and Rava, as well as other people who wanted to see how those islands were represented on maps in the past. Vladimir Alavanja provided the idea for the exhibition, and its form and location were arranged with Josip Faričić from the Department of Geography of the University of Zagreb. Two passenger saloons aboard Anamarija were chosen as the location of the exhibition in order to present the exhibits to the inhabitants and frequent travellers from Iž to Rava in the way that the maps were contextualized in the space they represent. The exhibits were placed as sections of high-quality prints of 30 selected maps and charts. Sections of old maps were printed on a high-quality paper, framed and hanged in place of curtains on ships windows. Art historian Koraljka Alavanja conceived such an artistic arrangement.

  6. Mapping strategies: Chromosome 16 workshop

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The following topics from a workshop on chromosome 16 are briefly discussed: genetic map of chromosome 16; chromosome breakpoint map of chromosome 16; integrated physical/genetic map of chromosome 16; pulsed field map of the 16p13.2--p13.3 region (3 sheets); and a report of the HGM10 chromosome 16 committee.

  7. Understanding Bowel Preparation

    Science.gov (United States)

    ... EURP) Excellence in GI Practice Operations Recognition Program (PRP) Tools to Educate Patients Polyp Information Sheets Foundation ... at ASGE Site Map Learn More ARIA Industry Training Newsroom Find a Doc Transmission of CRE bacteria ...

  8. Web Interactive Campus Map

    Directory of Open Access Journals (Sweden)

    Marylene S. Eder

    2015-03-01

    Full Text Available Abstract Interactive campus map is a web based application that can be accessed through a web browser. With the Google Map Application Programming Interface availability of the overlay function has been taken advantage to create custom map functionalities. Collection of building points were gathered for routing and to create polygons which serves as a representation of each building. The previous campus map provides a static visual representation of the campus. It uses legends building name and its corresponding building number in providing information. Due to its limited capabilities it became a realization to the researchers to create an interactive campus map.Storing data about the building room and staff information and university events and campus guide are among the primary features that this study has to offer. Interactive Web-based Campus Information System is intended in providing a Campus Information System.It is open to constant updates user-friendly for both trained and untrained users and capable of responding to all needs of users and carrying out analyses. Based on the data gathered through questionnaires researchers analyzed the results of the test survey and proved that the system is user friendly deliver information to users and the important features that the students expect.

  9. Introduction to "Mapping Vietnameseness"

    Directory of Open Access Journals (Sweden)

    Hue-Tam Ho Tai

    2016-09-01

    Full Text Available Vietnam and China are currently engaged in a map war, with each country using ancient maps to buttress its claims to territorial sovereignty over some uninhabited islands in the South China Sea (in Chinese terminology, also known as the Eastern Sea (in Vietnamese. But what do maps in fact represent? What is meant by “territory”? How are territorial limits conceived? These questions were raised in a May 2015 workshop inspired by Thongchai Winichakul’s Siam Mapped: A History of the Geo-Body of a Nation (1994, a groundbreaking book that traces the transformation of Thai geographical consciousness as a result of Siam’s encounter with Western powers in the nineteenth century. While many of Thongchai’s insights apply to the Vietnamese case, as the first of the three articles included in this special issue of Cross-Currents shows, some of the 2015 workshop participants’ conclusions departed from his, especially regarding the formation of a Vietnamese geographical consciousness before the colonial period.[i] This is true of the other two papers, which focus specifically on the construction of borders and the associated production of maps in the nineteenth century before French colonial conquest... Notes 1 Thanks are due to the Max Planck Institute for the Study of Religious and Ethnic Change in Gottingen, Germany, for its gracious hosting and generous funding of the conference, together with the Asia Center of Harvard University.

  10. Maps, immersions and permutations

    CERN Document Server

    Coquereaux, Robert

    2015-01-01

    We consider the problem of counting and of listing topologically inequivalent "planar" {4-valent} maps with a single component and a given number n of vertices. This enables us to count and to tabulate immersions of a circle in a sphere (spherical curves), extending results by Arnold and followers. Different options where the circle and/or the sphere are/is oriented are considered in turn, following Arnold's classification of the different types of symmetries. We also consider the case of bicolourable and bicoloured maps or immersions, where faces are bicoloured. Our method extends to immersions of a circle in a higher genus Riemann surface. There the bicolourability is no longer automatic and has to be assumed. We thus have two separate countings in non zero genus, that of bicolourable maps and that of general maps. We use a classical method of encoding maps in terms of permutations, on which the constraints of "one-componentness" and of a given genus may be applied. Depending on the orientation issue and on...

  11. GIS and Remote Sensing for Malaria Risk Mapping, Ethiopia

    Science.gov (United States)

    Ahmed, A.

    2014-11-01

    Integrating malaria data into a decision support system (DSS) using Geographic Information System (GIS) and remote sensing tool can provide timely information and decision makers get prepared to make better and faster decisions which can reduce the damage and minimize the loss caused. This paper attempted to asses and produce maps of malaria prone areas including the most important natural factors. The input data were based on the geospatial factors including climatic, social and Topographic aspects from secondary data. The objective of study is to prepare malaria hazard, Vulnerability, and element at risk map which give the final output, malaria risk map. The malaria hazard analyses were computed using multi criteria evaluation (MCE) using environmental factors such as topographic factors (elevation, slope and flow distance to stream), land use/ land cover and Breeding site were developed and weighted, then weighted overlay technique were computed in ArcGIS software to generate malaria hazard map. The resulting malaria hazard map depicts that 19.2 %, 30.8 %, 25.1 %, 16.6 % and 8.3 % of the District were subjected to very high, high, moderate, low and very low malaria hazard areas respectively. For vulnerability analysis, health station location and speed constant in Spatial Analyst module were used to generate factor maps. For element at risk, land use land cover map were used to generate element at risk map. Finally malaria risk map of the District was generated. Land use land cover map which is the element at risk in the District, the vulnerability map and the hazard map were overlaid. The final output based on this approach is a malaria risk map, which is classified into 5 classes which is Very High-risk area, High-risk area, Moderate risk area, Low risk area and Very low risk area. The risk map produced from the overlay analysis showed that 20.5 %, 11.6 %, 23.8 %, 34.1 % and 26.4 % of the District were subjected to very high, high, moderate, low and very low

  12. Using Concept Maps to Engage Adult Learners in Critical Analysis

    Science.gov (United States)

    Yelich Biniecki, Susan M.; Conceição, Simone C. O.

    2016-01-01

    An understanding of learning theories can help adult educators become more effective practitioners and meet the needs of the learners they serve. Adult educators who understand how individuals learn can be better prepared to use effective strategies during the learning process. This article addresses the use of concept maps as a strategy to engage…

  13. Computer Map Typing - Optimizing the Correlation Coefficient Threshold,

    Science.gov (United States)

    the procedures which would be employed in the preparation of each catalog. This paper addresses only one of these questions; ’What correlation ... coefficient threshold provides the best of map types.’ The choice of an appropriate threshold value is, at best, a compromise. This paper shows that a

  14. Cognitions of Expert Supervisors in Academe: A Concept Mapping Approach

    Science.gov (United States)

    Kemer, Gülsah; Borders, L. DiAnne; Willse, John

    2014-01-01

    Eighteen expert supervisors reported their thoughts while preparing for, conducting, and evaluating their supervision sessions. Concept mapping (Kane & Trochim, [Kane, M., 2007]) yielded 195 cognitions classified into 25 cognitive categories organized into 5 supervision areas: conceptualization of supervision, supervisee assessment,…

  15. Ergodicity of polygonal slap maps

    Science.gov (United States)

    Del Magno, Gianluigi; Lopes Dias, João; Duarte, Pedro; Gaivão, José Pedro

    2014-08-01

    Polygonal slap maps are piecewise affine expanding maps of the interval obtained by projecting the sides of a polygon along their normals onto the perimeter of the polygon. These maps arise in the study of polygonal billiards with non-specular reflection laws. We study the absolutely continuous invariant probabilities (acips) of the slap maps for several polygons, including regular polygons and triangles. We also present a general method for constructing polygons with slap maps with more than one ergodic acip.

  16. The World Stress Map

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Knowledge of the stress field in the Earth's crust is a key issue for the understanding of geodynamic processes,seismic hazard assessment, and stability of underground openings such as waste disposals, tunnels, mines or wells, and reservoir management. The World Stress Map project is a collaborative project of academia,industry and governmental organizations that aims to understand the states and sources of tectonic stresses in the Earth's crust. We present the Worm Stress Map at 1:46,000,000 scale as a result of more than two decades of international collaboration. The map reveals that the first-order pattern of stress is of plate-wide scale, indicating that plate boundary forces are the major control of the stress orientations and the tectonic regime.

  17. Geologic map of Great Sand Dunes National Park, Colorado

    Science.gov (United States)

    Madole, Richard F.; VanSistine, D. Paco; Romig, Joseph H.

    2016-10-20

    Geologic mapping was begun after a range fire swept the area of what is now the Great Sand Dunes National Park in April 2000. The park spans an area of 437 square kilometers (or about 169 square miles), of which 98 percent is blanketed by sediment of Quaternary age, the Holocene and Pleistocene Epochs; hence, this geologic map of the Great Sand Dunes National Park is essentially a surficial geologic map. These surficial deposits are diverse and include sediment of eolian (windblown), alluvial (stream and sheetwash), palustrine (wetlands and marshes), lacustrine (lake), and mass-wasting (landslides) origin. Sediment of middle and late Holocene age, from about 8,000 years ago to the present, covers about 80 percent of the park.Fluctuations in groundwater level during Holocene time caused wetlands on the nearby lowland that bounds the park on the west to alternately expand and contract. These fluctuations controlled the stability or instability of eolian sand deposits on the downwind (eastern) side of the lowland. When groundwater level rose, playas became lakes, and wet or marshy areas formed in many places. When the water table rose, spring-fed streams filled their channels and valley floors with sediment. Conversely, when groundwater level fell, spring-fed streams incised their valley floors, and lakes, ponds, and marshes dried up and became sources of windblown sand.Discharge in streams draining the west flank of the Sangre de Cristo Range is controlled primarily by snowmelt and flow is perennial until it reaches the mountain front, beyond which streams begin losing water at a high rate as the water soaks into the creek beds. Even streams originating in the larger drainage basins, such as Sand and Medano Creeks, generally do not extend much more than 4 km (about 2.5 miles) beyond where they exit the mountains.The Great Sand Dunes contain the tallest dunes (maximum height about 750 feet, or 230 m) in North America. These dunes cover an area of 72 square kilometers

  18. Mapping your competitive position.

    Science.gov (United States)

    D'Aveni, Richard A

    2007-11-01

    A price-benefit positioning map helps you see, through your customers' eyes, how your product compares with all its competitors in a market. You can draw such a map quickly and objectively, without having to resort to costly, time-consuming consumer surveys or subjective estimates of the excellence of your product and the shortcomings of all the others. Creating a positioning map involves three steps: First, define your market to include everything your customers might consider to be your product's competitors or substitutes. Second, track the price your customers actually pay (wholesale or retail? bundled or unbundled?) and identify what your customers see as your offering's primary benefit. This is done through regression analysis, determining which of the product's attributes (as described objectively by rating services, government agencies, R&D departments, and the like) explains most of the variance in its price. Third, draw the map by plotting on a graph the position of every product in the market you've selected according to its price and its level of primary benefit, and draw a line that runs through the middle of the points. What you get is a picture of the competitive landscape of your market, where all the products above the line command a price premium owing to some secondary benefit customers value, and all those below the line are positioned to earn market share through lower prices and reduced secondary benefits. Using examples as varied as Harley-Davidson motorcycles, Motorola cell phones, and the New York restaurant market, Tuck professor D'Aveni demonstrates some of the many ways the maps can be used: to locate unoccupied or less-crowded spaces in highly competitive markets, for instance, or to identify opportunities created through changes in the relationship between the primary benefit and prices. The maps even allow companies to anticipate--and counter-- rivals' strategies. R eprint RO711G

  19. Neighborhood Mapping Tool

    Data.gov (United States)

    Department of Housing and Urban Development — This tool assists the public and Choice Neighborhoods applicants to prepare data to submit with their grant application by allowing applicants to draw the exact...

  20. Learning Bing maps API

    CERN Document Server

    Sinani, Artan

    2013-01-01

    This is a practical, hands-on guide with illustrative examples, which will help you explore the vast universe of Bing maps.If you are a developer who wants to learn how to exploit the numerous features of Bing Maps then this book is ideal for you. It can also be useful for more experienced developers who wish to explore other areas of the APIs. It is assumed that you have some knowledge of JavaScript, HTML, and CSS. For some chapters a working knowledge of .Net and Visual Studio is also needed.