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Sample records for suwannee river natural

  1. 2011 Suwannee River Water Management District Lidar: Upper Suwannee (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River project area in Florida. The entire survey area encompasses 1,151 square miles. The...

  2. Characterisation of Fe-oxide nanoparticles coated with humic acid and Suwannee River natural organic matter.

    Science.gov (United States)

    Chekli, Laura; Phuntsho, Sherub; Roy, Maitreyee; Shon, Ho Kyong

    2013-09-01

    Iron oxide nanoparticles are becoming increasingly popular for various applications including the treatment of contaminated soil and groundwater; however, their mobility and reactivity in the subsurface environment are significantly affected by their tendency to aggregate. One solution to overcome this issue is to coat the nanoparticles with dissolved organic matter (DOM). The advantages of DOM over conventional surface modifiers are that DOM is naturally abundant in the environment, inexpensive, non-toxic and readily adsorbed onto the surface of metal oxide nanoparticles. In this study, humic acid (HA) and Suwannee River natural organic matter (SRNOM) were tested and compared as surface modifiers for Fe2O3 nanoparticles (NPs). The DOM-coated Fe2O3 NPs were characterised by various analytical methods including: flow field-flow fractionation (FlFFF), high performance size exclusion chromatography (HPSEC) and Fourier transform infrared spectroscopy (FTIR). The stability of the coated NPs was then evaluated by assessing their aggregation and disaggregation behaviour over time. Results showed that both HA and SRNOM were rapidly and readily adsorbed on the surface of Fe2O3 NPs, providing electrosteric stabilisation over a wide range of pH. HPSEC results showed that the higher molecular weight components of DOM were preferentially adsorbed onto the surface of Fe2O3. As SRNOM consists of macromolecules with a higher molecular weight than HA, the measured size of the SRNOM-coated Fe2O3 NPs was 30% larger than the HA-coated Fe2O3 NPs. FTIR results indicated the occurrence of hydrogen bonding arising from electrostatic interaction between the DOM and Fe2O3 NPs. Finally, a stability study showed that after 14 days, small agglomerates and aggregates were formed. The HA-coated Fe2O3 NPs formed agglomerates which were easily disaggregated using a vortex mixer, with the coated NPs returning to their initial size. However, SRNOM-coated Fe2O3 NPs were only partially disaggregated

  3. 2008 Florida Division of Emergency Management Lidar: Middle Suwannee River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LiDAR Survey for the Suwannee River Water Management District (SRWMD), Florida. The LiDAR aerial acquisition was conducted in January of 2008, and the breaklines and...

  4. 2012 Suwannee River Water Management District (SRWMD) Lidar: Bradford (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS - Suwannee River Water Management District Contract No.G10PC00093, Task Order No.G12PD00242 Prime Contractor: Digital Aerial Solutions (DAS) Sub-Contractor:...

  5. Progress Report: Chemical contaminants study of the Withlacoochee/Upper Suwannee River Systems reconnaissance field evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Withlacoochee/Upper Suwannee River component of the Suwannee River Basin contains valuable habitat utilized by important trust resources, as well as species of...

  6. 2013 Suwannee River Water Management District Lidar: Obrien (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of Suwannee River G13PD00141 1.0 Meter LiDAR Survey Area 1, Classified Point Cloud, in north-central...

  7. 2013 Suwannee River Water Management District Lidar: Ocean Pond (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of Suwannee River G13PD00141 1.0 Meter LiDAR Survey Area 3, Classified Point Cloud, in north-central...

  8. Suwannee River Water Management District Lidar: Falmouth (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G12PD00242 1.0 Meter LiDAR Survey area 5 in north-central Florida and encompasses...

  9. 2011 USGS Topographic LiDAR: Suwannee River Expansion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Task Order No. G10PD00236 USGS Contract No. G10PC00093 The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River Expansion in...

  10. 2013 Suwannee River Water Management District Lidar: Greenville (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of Suwannee River G12PD00242 1.0 Meter LiDAR Survey Area 3, Classified Point Cloud, in north-central...

  11. 2013 Suwannee River Water Management District (SRWMD) Lidar: Ichetucknee (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G12PD00242 1.0 Meter LiDAR Survey area 2 in north-central Florida and encompasses...

  12. 2014 Suwannee River Water Management District Lidar: Cooks Hammock (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G14PD00206 0.7 Meter LiDAR Survey in central Florida and encompasses 571 square...

  13. 2013 Suwannee River Water Management District Lidar: Lee (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of Suwannee River G13PD00141 1.0 Meter LiDAR Survey Area 2, Classified Point Cloud, in north-central...

  14. 2013 Suwannee River Water Management District Lidar: Bell (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of Suwannee River G13PD00141 1.0 Meter LiDAR Survey Area 4, Classified Point Cloud, in north-central...

  15. Suwannee river basin and estuary integrated science workshop: September 22-24, 2004 Cedar Key, Florida

    Science.gov (United States)

    Katz, Brian; Raabe, Ellen

    2004-01-01

    In response to the growing number of environmental concerns in the mostly pristine Suwannee River Basin and the Suwannee River Estuary system, the States of Florida and Georgia, the Federal government, and other local organizations have identified the Suwannee River as an ecosystem in need of protection because of its unique biota and important water resources. Organizations with vested interests in the region formed a coalition, the Suwannee Basin Interagency Alliance (SBIA), whose goals are to promote coordination in the identification, management, and scientific knowledge of the natural resources in the basin and estuary. To date, an integrated assessment of the physical, biological, and water resources has not been completed. A holistic, multi-disciplinary approach is being pursued to address the research needs in the basin and estuary and to provide supportive data for meeting management objectives of the entire ecosystem. The USGS is well situated to focus on the larger concerns of the basin and estuary by addressing specific research questions linking water supply and quality to ecosystem function and health across county and state boundaries. A strategic plan is being prepared in cooperation with Federal, State, and local agencies to identify and implement studies to address the most compelling research issues and management questions, and to conduct fundamental environmental monitoring studies. The USGS, Suwannee River Water Management District and the Florida Marine Research Institute are co-sponsoring this scientific workshop on the Suwannee River Basin and Estuary to: Discuss current and past research findings, Identify information gaps and research priorities, and Develop an action plan for coordinated and relevant research activities in the future. This workshop builds on the highly successful basin-wide conference sponsored by the Suwannee Basin Interagency Alliance that was held three years ago in Live Oak, Florida. This years workshop will focus on

  16. Role of Temperature and Suwannee River Natural Organic Matter on Inactivation Kinetics of Rotavirus and Bacteriophage MS2 by Solar Irradiation

    KAUST Repository

    Romero, Ofelia C.

    2011-12-15

    Although the sunlight-mediated inactivation of viruses has been recognized as an important process that controls surface water quality, the mechanisms of virus inactivation by sunlight are not yet clearly understood. We investigated the synergistic role of temperature and Suwannee River natural organic matter (SRNOM), an exogenous sensitizer, for sunlight-mediated inactivation of porcine rotavirus and MS2 bacteriophage. Upon irradiation by a full spectrum of simulated sunlight in the absence of SRNOM and in the temperature range of 14-42 °C, high inactivation rate constants, kobs, of MS2 (k obs ≤ 3.8 h-1 or 1-log10 over 0.6 h) and rotavirus (kobs ≤ 11.8 h-1 or ∼1-log10 over 0.2 h) were measured. A weak temperature (14-42 °C) dependence of kobs values was observed for both viruses irradiated by the full sunlight spectrum. Under the same irradiation condition, the presence of SRNOM reduced the inactivation of both viruses due to attenuation of lower wavelengths of the simulated sunlight. For rotavirus and MS2 solutions irradiated by only UVA and visible light in the absence of SRNOM, inactivation kinetics were slow (kobs < 0.3 h-1 or <1-log10 unit reduction over 7 h) and temperature-independent for the range considered. Conversely, under UVA and visible light irradiation and in the presence of SRNOM, temperature-dependent inactivation of MS2 was observed. For rotavirus, the SRNOM-mediated exogenous inactivation was only important at temperatures >33 °C, with low rotavirus kobs values (kobs ≈ 0.2 h-1; 1-log10 unit reduction over 12 h) for the temperature range of 14-33 °C. These kobs values increased to 0.5 h-1 at 43 °C and 1.5 h-1 (1-log10 reduction over 1.6 h) at 50 °C. While SRNOM-mediated exogenous inactivation of MS2 was triggered by singlet oxygen, the presence of hydrogen peroxide was important for rotavirus inactivation in the 40-50 °C range. © 2011 American Chemical Society.

  17. Suwannee River flow variability 1550-2005 CE reconstructed from a multispecies tree-ring network

    Science.gov (United States)

    Harley, Grant L.; Maxwell, Justin T.; Larson, Evan; Grissino-Mayer, Henri D.; Henderson, Joseph; Huffman, Jean

    2017-01-01

    Understanding the long-term natural flow regime of rivers enables resource managers to more accurately model water level variability. Models for managing water resources are important in Florida where population increase is escalating demand on water resources and infrastructure. The Suwannee River is the second largest river system in Florida and the least impacted by anthropogenic disturbance. We used new and existing tree-ring chronologies from multiple species to reconstruct mean March-October discharge for the Suwannee River during the period 1550-2005 CE and place the short period of instrumental flows (since 1927 CE) into historical context. We used a nested principal components regression method to maximize the use of chronologies with varying time coverage in the network. Modeled streamflow estimates indicated that instrumental period flow conditions do not adequately capture the full range of Suwannee River flow variability beyond the observational period. Although extreme dry and wet events occurred in the gage record, pluvials and droughts that eclipse the intensity and duration of instrumental events occurred during the 16-19th centuries. The most prolonged and severe dry conditions during the past 450 years occurred during the 1560s CE. In this prolonged drought period mean flow was estimated at 17% of the mean instrumental period flow. Significant peaks in spectral density at 2-7, 10, 45, and 85-year periodicities indicated the important influence of coupled oceanic-atmospheric processes on Suwannee River streamflow over the past four centuries, though the strength of these periodicities varied over time. Future water planning based on current flow expectations could prove devastating to natural and human systems if a prolonged and severe drought mirroring the 16th and 18th century events occurred. Future work in the region will focus on updating existing tree-ring chronologies and developing new collections from moisture-sensitive sites to improve

  18. The effects of monovalent and divalent cations on the stability of silver nanoparticles formed from direct reduction of silver ions by Suwannee River humic acid/natural organic matter

    Energy Technology Data Exchange (ETDEWEB)

    Akaighe, Nelson [Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States); Depner, Sean W.; Banerjee, Sarbajit [Department of Chemistry, 410 Natural Sciences Complex, University at Buffalo, The State University of New York, Buffalo, NY 14260-3000 (United States); Sharma, Virender K. [Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States); Sohn, Mary, E-mail: msohn@fit.edu [Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States)

    2012-12-15

    The formation and characterization of AgNPs (silver nanoparticles) formed from the reduction of Ag{sup +} by SRNOM (Suwannee River natural organic matter) is reported. The images of SRNOM-formed AgNPs and the selected area electron diffraction (SAED) were captured by high resolution transmission electron microscopy (HRTEM). The colloidal and chemical stability of SRNOM- and SRHA (Suwannee River humic acid)-formed AgNPs in different ionic strength solutions of NaCl, KCl, CaCl{sub 2} and MgCl{sub 2} was investigated in an effort to evaluate the key fate and transport processes of these nanoparticles in natural aqueous environments. The aggregation state, stability and sedimentation rate of the AgNPs were monitored by Dynamic Light Scattering (DLS), zeta potential, and UV-vis measurements. The results indicate that both types of AgNPs are very unstable in high ionic strength solutions. Interestingly, the nanoparticles appeared more unstable in divalent cation solutions than in monovalent cation solutions at similar concentrations. Furthermore, the presence of SRNOM and SRHA contributed to the nanoparticle instability at high ionic strength in divalent metallic cation solutions, most likely due to intermolecular bridging with the organic matter. The results clearly suggest that changes in solution chemistry greatly affect nanoparticle long term stability and transport in natural aqueous environments. Highlights: Black-Right-Pointing-Pointer Formation of SRNOM-AgNPs under environmentally relevant conditions Black-Right-Pointing-Pointer Influence of monovalent versus divalent cations on SRHA- and SRNOM-AgNP stability Black-Right-Pointing-Pointer Effect of AgNPs on organic matter removal from water columns.

  19. Magnitude and frequency of floods in the Suwannee River Water Management District, Florida

    Science.gov (United States)

    Giese, G.L.; Franklin, Marvin A.

    1996-01-01

    Flood-frequency statistics for 2-, 5-, 10-, 25-, 50-. 100-, 200-, and 500-year recurrence intervals, based on three methods of analysis, are presented for 25 continuous-record and seven peak flow partial-record gaging stations in the Suwannee River Water Management District. The first method, for gaged stations, utilizes station records; the second method, for ungaged sites, utilizes regional regression analysis; and the third method uses a weighted combination of the station and regional values. Because the weighted values utilize two more or less independent estimates of the peak flow statistic, they are considered more accurate than the station estimates or the regression estimates alone. Also, the use of another weighting scheme to improve estimates of flood frequency statistics at ungaged sites is demonstrated. The karstic nature of much of the Suwannee River Water Management District significantly attenuates flood peaks in some streams by providing substantial subsurface storage when river stages are high. At such times, springs discharging into rivers may reverse flow temporarily and become sinks.

  20. MODFLOW datasets for simulations of groundwater flow with downscaled global climate model data for the Suwannee River Basin, Florida

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A previously-developed groundwater model of the Suwannee River Basin was modified and calibrated to represent transient conditions. A simulation of recent conditions...

  1. Photochemical behavior of carbon nanotubes in natural waters: reactive oxygen species production and effects on •OH generation by Suwannee River fulvic acid, nitrate, and Fe (III).

    Science.gov (United States)

    Zhou, Lei; Zhang, Ya; Wang, Qi; Ferronato, Corinne; Yang, Xi; Chovelon, Jean-Marc

    2016-10-01

    The photochemical activities of three kinds of carbon nanotubes (CNTs) were investigated in the present study. Efficient procedures of dispersing the three kinds of carbon nanotubes in water were established, and the quantitative analysis methods were also developed by TOC-absorbance method. High pH value or low ionic strength of the colloidal solutions facilitated the dispersion of CNTs. The suspensions of three kinds of CNTs could generate singlet oxygen ((1)O2) and hydroxyl radical (•OH) under irradiation of simulated sunlight, while superoxide radical (O2 (•-)) was not detected. The steady-state concentrations of (1)O2 and •OH generated by these CNTs were also determined. The presence of CNTs in natural waters can affect the photochemical behavior of water constituents, such as nitrate, dissolved organic matter, and Fe(3+). Specifically, in nitrate solution, the presence of CNTs could inhibit the generation of •OH by nitrate through light screening effect, while the quenching effect of hydroxyl radicals by CNTs was not observed. Besides light screening effect, the three kinds of CNTs used in the experiments also have a strong inhibiting effect on the ability of DOM to produce •OH by binding to the active sites. Moreover, the adsorption of Fe(3+) on MWCNT-OH and MWCNT-COOH could lead to its inactivation of formation of •OH in acidic conditions. However, the presence of the three kinds of CNTs did not affect the ligand-to-metal charge transfer (LMCT) reaction of DOM-Fe (III) complex.

  2. Models of metal binding structures in fulvic acid from the Suwannee River, Georgia

    Energy Technology Data Exchange (ETDEWEB)

    Leenheer, J.A.; Brown, G.K.; Cabaniss, S.E. [Geological Survey, Denver, CO (United States); MacCarthy, P. [Colorado School of Mines, Golden, CO (United States). Dept. of Chemistry

    1998-08-15

    Fulvic acid, isolated from the Suwannee River, Georgia, was assessed for its ability to bind Ca{sup 2+}, Cd{sup 2+}, Cu{sup 2+}, Ni{sup 2+}, and Zn{sup 2+} ions at pH 6 before and after extensive fractionation that was designed to reveal the nature of metal binding functional groups. The binding constant for Ca{sup 2+} ion had the greatest increase of all the ions in a metal binding fraction that was selected for intensive characterization for the purpose of building quantitative average model structures. The metal binding fraction was characterized by quantitative {sup 13}C NMR, {sup 1}H NMR, and FT-IR spectrometry and elemental, titrimetric, and molecular weight determinations. The characterization data revealed that carboxyl groups were clustered in short-chain aliphatic dibasic acid structures. The Ca{sup 2+} binding data suggested that ether-substituted oxysuccinic acid structures are good models for the metal binding sites at pH 6. Structural models were derived based upon oxidation and photolytic rearrangements of cutin, lignin, and tannin precursors. These structural models rich in substituted dibasic acid structures revealed polydentate binding sites with the potential for both inner-sphere and outer-sphere type binding. The majority of the fulvic acid molecule was involved with metal binding rather than a small substructural unit.

  3. Interactions between Rotavirus and Suwannee River Organic Matter: Aggregation, Deposition, and Adhesion Force Measurement

    KAUST Repository

    Gutierrez, Leonardo

    2012-08-21

    Interactions between rotavirus and Suwannee River natural organic matter (NOM) were studied by time-resolved dynamic light scattering, quartz crystal microbalance, and atomic force microscopy. In NOM-containing NaCl solutions of up to 600 mM, rotavirus suspension remained stable for over 4 h. Atomic force microscopy (AFM) measurement for interaction force decay length at different ionic strengths showed that nonelectrostatic repulsive forces were mainly responsible for eliminating aggregation in NaCl solutions. Aggregation rates of rotavirus in solutions containing 20 mg C/L increased with divalent cation concentration until reaching a critical coagulation concentration of 30 mM CaCl2 or 70 mM MgCl2. Deposition kinetics of rotavirus on NOM-coated silica surface was studied using quartz crystal microbalance. Experimental attachment efficiencies for rotavirus adsorption to NOM-coated surface in MgCl2 solution were lower than in CaCl2 solution at a given divalent cation concentration. Stronger adhesion force was measured for virus-virus and virus-NOM interactions in CaCl2 solution compared to those in MgCl2 or NaCl solutions at the same ionic strength. This study suggested that divalent cation complexation with carboxylate groups in NOM and on virus surface was an important mechanism in the deposition and aggregation kinetics of rotavirus. © 2012 American Chemical Society.

  4. The Gulf Sturgeon in the Suwannee River - Questions and Answers

    Science.gov (United States)

    Sulak, Kenneth J.; Randall, Michael T.

    2009-01-01

    Sturgeons and paddlefishes are modern descendants of an ancient group of freshwater fishes, the Chondrostei (a group of bony fishes with mostly cartilaginous skeletons). Sturgeons evolved during the Age of the Dinosaurs, and have prospered in the large rivers and lakes of North America, Europe and Asia for 200 million years. Together with alligators and crocodiles, they survived the mass extinction at the end of the Mesozoic Era, when the dinosaurs and many other groups of animals disappeared forever. They originated prior to the creation of the Atlantic Ocean, when the Northern Hemisphere supercontinent Pangea broke into North America and Eurasia. Most sturgeons are highly specialized to feed in the sediment on small invertebrate prey, a radical evolutionary departure from most of their fish-eating ancestors.

  5. Molecular Signature of Organic Carbon Along a Salinity Gradient in Suwannee River Plume

    Science.gov (United States)

    Liu, Y.; Bianchi, T. S.; Ward, N. D.; Arellano, A. R.; Paša-Tolić, L.; Tolic, N.; Kuo, L. J.

    2016-12-01

    Humic and fulvic acid isolates from Suwannee River dissolved organic matter (DOM) have served as reference standards for the International Humic Substances Society (IHSS) for many decades. The large database on Suwannee DOM provides an excellent framework to further expand the application of Fourier transform ion cyclotron mass spectrometry (FT-ICR-MS) in characterizing the chemical composition of aquatic DOM. In this study, we examined the DOM signature of the lower Suwannee River and plume region at 5 stations along a salinity gradient (0 to 28) using FT-ICR-MS. The chemical characteristics of DOM show distinct differences across this steep salinity gradient. In general, samples collected from the coastal station have lower carbon number and are less aromatic. Molecular level analysis reveals that the magnitude weighted proportion of lipids increased as salinity increased. Interestingly, a similar trend was observed for lignin-like compounds. Target quantification of lignin-phenols showed that while the concentrations of these compounds were lower at the coastal station, the DOC-normalized concentrations were not significantly different between the river and coastal stations. In addition to traditional DOM moieties, we identified for the first time, halogenated organic compounds (HOC). We observed more chlorinated compounds in DOM and increased Cl/C as salinity increased. A relatively high proportion of halogenated lipids (compared to non-halogenated) were observed in the total pool of HOC across all stations. Although not significant in relative proportion, halogenated lignin-like compounds were the most abundant HOC moieties in our samples. CO2 concentrations decreased and became more 13C-enriched along the salinity gradient, ranging from 3,990 ppm (13CO2 = -17.3‰) at salinity 0 to 520 ppm (13CO2 = -7.5‰) at salinity 28, indicating high levels of DOM degradation in the river and a shift to primary production in the marine receiving waters, which is

  6. Discovery of South American suckermouth armored catfishes (Loricariidae, Pterygoplichthys spp.) in the Santa Fe River drainage, Suwannee River basin, USA

    Science.gov (United States)

    Nico, Leo G.; Butt, Peter L.; Johnston, Gerald R.; Jelks, Howard L.; Kail, Matthew; Walsh, Stephen J.

    2012-01-01

    We report on the occurrence of South American suckermouth armored catfishes (Loricariidae) in the Suwannee River basin, southeastern USA. Over the past few years (2009-2012), loricariid catfishes have been observed at various sites in the Santa Fe River drainage, a major tributary of the Suwannee in the state of Florida. Similar to other introduced populations of Pterygoplichthys, there is high likelihood of hybridization. To date, we have captured nine specimens (270-585 mm, standard length) in the Santa Fe River drainage. One specimen taken from Poe Spring best agrees with Pterygoplichthys gibbiceps (Kner, 1854) or may be a hybrid with either P. pardalis or P. disjunctivus. The other specimens were taken from several sites in the drainage and include seven that best agree with Pterygoplichthys disjunctivus (Weber, 1991); and one a possible P. disjunctivus x P. pardalis hybrid. We observed additional individuals, either these or similar appearing loricariids, in Hornsby and Poe springs and at various sites upstream and downstream of the long (> 4 km) subterranean portion of the Santa Fe River. These specimens represent the first confirmed records of Pterygoplichthys in the Suwannee River basin. The P. gibbiceps specimen represents the first documented record of an adult or near adult of this species in open waters of North America. Pterygoplichthys disjunctivus or its hybrids (perhaps hybrid swarms) are already abundant and widespread in other parts of peninsular Florida, but the Santa Fe River represents a northern extension of the catfish in the state. Pterygoplichthys are still relatively uncommon in the Santa Fe drainage and successful reproduction not yet documented. However, in May 2012 we captured five adult catfish (two mature or maturing males and three gravid females) from a single riverine swallet pool. One male was stationed at a nest burrow (no eggs present). To survive the occasional harsh Florida winters, these South American catfish apparently use

  7. Copper binding by dissolved organic matter. I. Suwannee River fulvic acid equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Cabaniss, S.E.; Shuman, M.S.

    1988-01-01

    A cupric ion-selective electrode measured free Cu in solutions of Suwannee River fulvic acid (FA) in a series of 30 titrations carried out both at variable and at constant (5.14, 7.00, 8.44) pH. Total Cu varied 0.1-100 ..mu..m, dissolved organic carbon (DOC) 1-10 mg C/l, Ca and Mg 0-10 mM, and ionic strength 0.005-0.1. Copper complexation by FA is first order in DOC for 1-10 mg C/liter, and variable-order in pH. Increasing Ca/sup + +/ or Mg/sup + +/ from 0 to 10 mM slightly increases Cu/sup + +/ activity, while increasing ionic strength from 0.005 to 0.1 significantly increases Cu/sup + +/ activity. An empirical N-site model was calibrated using a pooled set of six titrations with varying pH and DOC. Five binding components of varying proton dependence predict Cu binding by FA over a range of pH, DOC and total Cu in two verification tests of the model parameters. Parameters in this and other models tested are only empirical constructs.

  8. Environmental Nitrogen Losses from Commercial Crop Production Systems in the Suwannee River Basin of Florida.

    Science.gov (United States)

    Prasad, Rishi; Hochmuth, George J

    2016-01-01

    The springs and the Suwannee river of northern Florida in Middle Suwanee River Basin (MSRB) are among several examples in this planet that have shown a temporal trend of increasing nitrate concentration primarily due to the impacts of non-point sources such as agriculture. The rate of nitrate increase in the river as documented by Ham and Hatzell (1996) was 0.02 mg N L-1 y-1. Best management practices (BMPs) for nutrients were adopted by the commercial farms in the MSRB region to reduce the amounts of pollutants entering the water bodies, however the effectiveness of BMPs remains a topic of interest and discussion among the researchers, environmental administrators and policy makers about the loads of nitrogen entering into groundwater and river systems. Through this study, an initiative was taken to estimate nitrogen losses into the environment from commercial production systems of row and vegetable crops that had adopted BMPs and were under a presumption of compliance with state water quality standards. Nitrogen mass budget was constructed by quantifying the N sources and sinks for three crops (potato (Solanum tuberosum L.), sweet corn (Zea mays L.) and silage corn (Zea mays L.)) over a four year period (2010-2013) on a large representative commercial farm in northern Florida. Fertilizer N was found to be the primary N input and represented 98.0 ± 1.4, 91.0 ± 13.9, 78.0 ± 17.3% of the total N input for potato, sweet corn, and silage corn, respectively. Average crop N uptake represented 55.5%, 60.5%, and 65.2% of the mean total input N whereas average mineral N left in top 0.3 m soil layer at harvest represented 9.1%, 4.5%, and 2.6% of the mean total input N. Mean environmental N losses represented 35.3%, 34.3%, and 32.7% of the mean total input N for potato, sweet corn, and silage corn, respectively. Nitrogen losses showed a linear trend with increase in N inputs. Although, there is no quick fix for controlling N losses from crop production in MSRB, the

  9. Concentrations and distributions of metals associated with dissolved organic matter from the Suwannee River (GA, USA)

    Science.gov (United States)

    Kuhn, M. Keshia; Neubauer, Elisabeth; Hofmann, Thilo; von der Kammer, Frank; Aiken, George R.; Maurice, Patricia A.

    2015-01-01

    Concentrations and distributions of metals in Suwannee River (SR) raw filtered surface water (RFSW) and dissolved organic matter (DOM) processed by reverse osmosis (RO), XAD-8 resin (for humic and fulvic acids [FA]), and XAD-4 resin (for “transphilic” acids) were analyzed by asymmetrical flow field-flow fractionation (AsFlFFF). SR samples were compared with DOM samples from Nelson's Creek (NLC), a wetland-draining stream in northern Michigan; previous International Humic Substances Society (IHSS) FA and RO samples from the SR; and an XAD-8 sample from Lake Fryxell (LF), Antarctica. Despite application of cation exchange during sample processing, all XAD and RO samples contained substantial metal concentrations. AsFlFFF fractograms allowed metal distributions to be characterized as a function of DOM component molecular weight (MW). In SR RFSW, Fe, Al, and Cu were primarily associated with intermediate to higher than average MW DOM components. SR RO, XAD-8, and XAD-4 samples from May 2012 showed similar MW trends for Fe and Al but Cu tended to associate more with lower MW DOM. LF DOM had abundant Cu and Zn, perhaps due to amine groups that should be present due to its primarily algal origins. None of the fractograms showed obvious evidence for mineral nanoparticles, although some very small mineral nanoparticles might have been present at trace concentrations. This research suggests that AsFlFFF is important for understanding how metals are distributed in different DOM samples (including IHSS samples), which may be key to metal reactivity and bioavailability.

  10. TiO2 nanoparticles aggregation and disaggregation in presence of alginate and Suwannee River humic acids. pH and concentration effects on nanoparticle stability.

    Science.gov (United States)

    Loosli, Frédéric; Le Coustumer, Philippe; Stoll, Serge

    2013-10-15

    The behavior of manufactured TiO2 nanoparticles is studied in a systematic way in presence of alginate and Suwannee River humic acids at variable concentrations. TiO2 nanoparticles aggregation, disaggregation and stabilization are investigated using dynamic light scattering and electrophoretic experiments allowing the measurement of z-average hydrodynamic diameters and zeta potential values. Stability of the TiO2 nanoparticles is discussed by considering three pH-dependent electrostatic scenarios. In the first scenario, when pH is below the TiO2 nanoparticle point of zero charge, nanoparticles exhibit a positively charged surface whereas alginate and Suwannee River humic acids are negatively charged. Fast adsorption at the TiO2 nanoparticles occurs, promotes surface charge neutralization and aggregation. By increasing further alginate and Suwannee River humic acids concentrations charge inversion and stabilization of TiO2 nanoparticles are obtained. In the second electrostatic scenario, at the surface charge neutralization pH, TiO2 nanoparticles are rapidly forming aggregates. Adsorption of alginate and Suwannee River humic acids on aggregates leads to their partial fragmentation. In the third electrostatic scenario, when nanoparticles, alginate and Suwannee River humic acids are negatively charged, only a small amount of Suwannee River humic acids is adsorbed on TiO2 nanoparticles surface. It is found that the fate and behavior of individual and aggregated TiO2 nanoparticles in presence of environmental compounds are mainly driven by the complex interplay between electrostatic attractive and repulsive interactions, steric and van der Waals interactions, as well as concentration ratio. Results also suggest that environmental aquatic concentration ranges of humic acids and biopolymers largely modify the stability of aggregated or dispersed TiO2 nanoparticles. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. MODFLOW datasets for simulations of groundwater flow with downscaled global climate model data for the Suwannee River Basin, Florida

    Science.gov (United States)

    Swain, Eric D.; Davis, J. Hal

    2016-01-01

    A previously-developed groundwater model of the Suwannee River Basin was modified and calibrated to represent transient conditions. A simulation of recent conditions was developed for the 372-month period 1970-2000, and was compared with a simulation of future conditions for a similar-length period 2039-2069, which uses downscaled GCM (Global Climate Model) data. The MODFLOW groundwater-simulation code was used in both of these simulations, and two different MODFLOW boundary condition “packages” (River and Streamflow Routing Packages) were used to represent interactions between surface-water and groundwater features. The parameters for the simulation of future conditions were developed from dynamically downscaled precipitation and evapotranspiration data generated by the Community Climate System Model. The model was developed to examine the effect of downscaled climate model data on the predictions of future hydrology in the Suwannee River Basin. The development of the model input and output files included in this data release are documented in a journal article for the American Journal of Climate Change. Support is provided for correcting errors in the data release and clarification of the modeling conducted by the U.S. Geological Survey. Users are encouraged to review the model documentation report to understand the purpose, construction, and limitations of this model.

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

    Science.gov (United States)

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

    2016-07-28

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

  13. Competition from Cu(II), Zn(II) and Cd(II) in Pb(II) binding to Suwannee River Fulvic Acid

    NARCIS (Netherlands)

    Chakraborty, P.; Chakrabarti, C.L.

    2008-01-01

    This is a study of trace metal competition in the complexation of Pb(II) by well-characterized humic substances, namely Suwannee River Fulvic Acid (SRFA) in model solutions. It was found that Cu(II) seems to compete with Pb(II) for strong binding sites of SRFA when present at the same concentration

  14. Strong-acid, carboxyl-group structures in fulvic acid from the Suwannee River, Georgia. 1. Minor structures

    Science.gov (United States)

    Leenheer, J.A.; Wershaw, R. L.; Reddy, M.M.

    1995-01-01

    An investigation of the strong-acid characteristics (pKa 3.0 or less) of fulvic acid from the Suwannee River, Georgia, was conducted. Quantitative determinations were made for amino acid and sulfur-containing acid structures, oxalate half-ester structures, malonic acid structures, keto acid structures, and aromatic carboxyl-group structures. These determinations were made by using a variety of spectrometric (13C-nuclear magnetic resonance, infrared, and ultraviolet spectrometry) and titrimetric characterizations on fulvic acid or fulvic acid samples that were chemically derivatized to indicate certain functional groups. Only keto acid and aromatic carboxyl-group structures contributed significantly to the strong-acid characteristics of the fulvic acid; these structures accounted for 43% of the strong-acid acidity. The remaining 57% of the strong acids are aliphatic carboxyl groups in unusual and/or complex configurations for which limited model compound data are available.

  15. Examination of Cadmium(II) Complexation by the Suwannee River Fulvic Acid Using 113Cd NMR Relaxation Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Otto, William; Burton, Sarah D.; Carper, W. R.; Larive, Cynthia K.

    2001-12-15

    Aquatic and terrestrial fulvic acids are environmentally important because they affect the bioavailability and transport of metal ions. Prior studies demonstrated that Cd(II) binds to the oxygen containing functional groups of fulvic acids. The complexation of Cd(II) is further investigated in this study using 113Cd NMR relaxation measurements. Spin-lattice (T1), and spin- spin (Tz) relaxation times are measured over a range of Cd(II):FA ratios. The results clearly indicate two types of Cd(II) binding sites for the Suwannee River FA (SRFA). A series of model ligands were also examined to gain further understanding of the two types of binding motifs present in the fulvic acid. The results for a model compound containing four carboxylate functionalities in near proximity, correspond very closely to the results obtained for the strong binding sites of the Cd(II)-SRF A complexes.

  16. Strong-acid, carboxyl-group structures in fulvic acid from the Suwannee River, Georgia. 2. Major structures

    Science.gov (United States)

    Leenheer, J.A.; Wershaw, R. L.; Reddy, M.M.

    1995-01-01

    Polycarboxylic acid structures that account for the strong-acid characteristics (pKa1 near 2.0) were examined for fulvic acid from the Suwannee River. Studies of model compounds demonstrated that pKa values near 2.0 occur only if the ??-ether or ??-ester groups were in cyclic structures with two to three additional electronegative functional groups (carboxyl, ester, ketone, aromatic groups) at adjacent positions on the ring. Ester linkage removal by alkaline hydrolysis and destruction of ether linkages through cleavage and reduction with hydriodic acid confirmed that the strong carboxyl acidity in fulvic acid was associated with polycarboxylic ??-ether and ??-ester structures. Studies of hypothetical structural models of fulvic acid indicated possible relation of these polycarboxylic structures with the amphiphilic and metal-binding properties of fulvic acid.

  17. Survival of hatchery Gulf sturgeon (Acipenser oxyrinchus desotoi Mitchill, 1815) in the Suwannee River, Florida: a 19-year evaluation

    Science.gov (United States)

    Sulak, Kenneth J.; Randall, Michael T.; Clugston, J.P.

    2014-01-01

    An experimental release of 1192 hatchery-reared, individually PIT tagged, 220 days old (296–337 mm TL) Gulf sturgeon, Acipenser oxyrinchus desotoi, was undertaken in 1992 in the Suwannee River, Florida. The original objectives of the 1992 release experiment were to: (1) evaluate survival rate of cultured Gulf sturgeon in the wild vs survival rate of their wild 1992 cohort counterparts, (2) determine the differential effect of release site within the river upon long-term survival, and (3) evaluate comparative growth rates of recaptured hatchery vs captured wild 1992 cohort Gulf sturgeon. The present investigation addressed those original objectives, plus an additional fourth objective: (4) evaluation of hatchery fish recapture rate change over the 19-year experiment. The primary objective was to determine efficacy of potential conservation aquaculture for this species in terms of long-term survival in the wild. Follow-up 1993–2011 gill net sampling in freshwater reaches (rkm 4–237) and the estuarine river mouth (rkm −6 to 4) yielded recaptures representing 13.0% of the total released. Mean annual hatchery fish mortality (including emigration) rate estimated for the 19-year period (1993–2011) was more than twice that for same cohort wild fish. Mark-recapture survival probability (phi) for hatchery fish, 1993–2011, was substantially lower (0.733) than for their wild counterparts (0.888). Mean annual hatchery fish recapture rate, as a percentage of all 1992 cohort fish recaptures, declined significantly after age-7, coinciding with age of onset of migration into the open Gulf of Mexico. Hypothesized causal factors may be differentially lower fitness in the marine habitat or permanent outmigration due to natal river imprinting failure. Hatchery fish recapture rates varied significantly for fish from the ten release sites, being highest near the river mouth, and lowest for the furthest upriver sites in the Suwannee River and its Santa Fe River tributary

  18. Experimental evidence for ternary colloid-facilitated transport of Th(IV) with hematite (α-Fe2O3) colloids and Suwannee River fulvic acid.

    Science.gov (United States)

    Emerson, Hilary P; Hickok, Katherine A; Powell, Brian A

    2016-12-01

    Previous field experiments have suggested colloid-facilitated transport via inorganic and organic colloids as the primary mechanism of enhanced actinide transport in the subsurface at former nuclear weapons facilities. In this work, research was guided by the hypothesis that humic substances can enhance tetravalent actinide (An(IV)) migration by coating and mobilizing natural colloids in environmental systems and increasing An(IV) sorption to colloids. This mechanism is expected to occur under relatively acidic conditions where organic matter can sorb and coat colloid surfaces and facilitate formation of ternary colloid-ligand-actinide complexes. The objective of this work was to examine Th transport through packed columns in the presence of hematite colloids and/or Suwannee River fulvic acid (SRFA). In the presence of SRFA, with or without hematite colloids, significant transport (>60% recovery within the effluent) of thorium occurred through quartz columns. It is notable that the SRFA contributed to increased transport of both Th and hematite colloids, while insignificant transport occurred in the absence of fulvic acid. Further, in the presence of a natural sandy sediment (as opposed to pure quartz), transport is negligible in the presence of SRFA due to interactions with natural, clay-sized sediment coatings. Moreover, this data shows that the transport of Th through quartz columns is enhanced in ternary Th-colloid-SRFA and binary Th-SRFA systems as compared to a system containing only Th. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. TiO2 nanoparticles aggregation and disaggregation in presence of alginate and Suwannee River humic acids. pH and concentration effects on nanoparticle stability

    OpenAIRE

    Loosli Frédéric LeCoustumer Philippe Stoll Serge

    2013-01-01

    The behavior of manufactured TiO2 nanoparticles is studied in a systematic way in presence of alginate and Suwannee River humic acids at variable concentrations. TiO2 nanoparticles aggregation disaggregation and stabilization are investigated using dynamic light scattering and electrophoretic experiments allowing the measurement of z average hydrodynamic diameters and zeta potential values. Stability of the TiO2 nanoparticles is discussed by considering three pH dependent electrostatic scenar...

  20. Characterization of Nanoparticles and Colloids in Aquatic Systems 1. Small Angle Neutron Scattering Investigations of Suwannee River Fulvic Acid Aggregates in Aqueous Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Diallo, Mamadou S. [California Institute of Technology, Materials and Process Simulation Center, Beckman Institute 139-74 (United States)], E-mail: diallo@wag.caltech.edu; Glinka, Charles J. [National Institute of Standards and Technology, Center for Neutron Research (United States); Goddard, William A. [California Institute of Technology, Materials and Process Simulation Center, Beckman Institute 139-74 (United States); Johnson, James H. [Howard University, Department of Civil Engineering (United States)

    2005-10-15

    Fulvic acids (FA) and humic acids (HA) constitute 30-50% of dissolved organic matter in natural aquatic systems. In aqueous solutions, a commonly accepted view is that FA and HA exist as soluble macroligands at low concentration and as supramolecular aggregates at higher concentration. The size, shape and structure of these aggregates are still the subject of ongoing debate in the environmental chemistry literature. In this article, we use small angle neutron scattering (SANS) to assess the effects of solute concentration, solution pH and background electrolyte (NaCl) concentration on the structures of Suwannee River FA (SRFA) aggregates in D{sub 2}O. The qualitative features of the SANS curves and data analysis are not consistent with the view point that SRFA forms micelle-like aggregates as its concentration in aqueous solution increases. We find that SRFA forms fractal aggregates in D{sub 2}0 with size greater than 242 nm. The SRFA aggregates undergo a significant degree of restructuring in compactness as solution pH, solute concentration and NaCl concentration increase.

  1. Aggregation and disaggregation of ZnO nanoparticles: influence of pH and adsorption of Suwannee River humic acid.

    Science.gov (United States)

    Mohd Omar, Fatehah; Abdul Aziz, Hamidi; Stoll, Serge

    2014-01-15

    The surface charge and average size of manufactured ZnO nanoparticles (NPs) were studied as a function of pH to understand the aggregation behavior and importance of the electrostatic interactions in solution. The interactions between ZnO and Suwannee River humic acid (SRHA) were then investigated under a range of environmentally relevant conditions with the ZnO nanoparticles pHPZC as the point of reference. The anionic charges carried by aquatic humic substances were found to play a major role in the aggregation and disaggregation of ZnO nanoparticles. At low concentrations of SRHA (<0.05 mg/L) and below the pHPZC, anionic SRHA was rapidly adsorbed onto the positively charged ZnO NPs hence promoting aggregation. With similar SHRA concentrations, at pHPZC, SRHA was able to control the suspension behavior of the ZnO and promote partial disaggregation in small volumes. This was more distinguishable when the pH was greater than pHPZC as SRHA formed a surface coating on the ZnO nanoparticles and enhanced stability via electrostatic and steric interactions. In most cases, the NP coating by SRHA induced disaggregation behavior in the ZnO nanoparticles and decreased the aggregate size in parallel to increasing SRHA concentrations. Results also suggest that environmental aquatic concentration ranges of humic acids largely modify the stability of aggregated or dispersed ZnO nanoparticles. © 2013.

  2. Fractionation of Suwannee River Fulvic Acid and Aldrich Humic Acid on α-Al2O3: Spectroscopic Evidence

    Energy Technology Data Exchange (ETDEWEB)

    Claret, F.; Schäfer, T; Brevet, J; Reiller, P

    2008-01-01

    Sorptive fractionation of Suwannee River Fulvic Acid (SRFA) and Purified Aldrich Humic Acid (PAHA) on a-Al2O3 at pH 6 was probed in the supernatant using different spectroscopic techniques. Comparison of dissolved organic carbon (DOC) analysis with UV/vis spectrophotometric measurements at 254 nm, including specific UV absorbance (SUVA) calculation, revealed a decrease in chromophoric compounds for the nonsorbed extracts after a 24 h contact time. This fractionation, only observable below a certain ratio between initial number of sites of humic substances and of a-Al2O3, seems to indicate a higher fractionation for PAHA. C(1s) near-edge X-ray absorption fine structure spectroscopy (NEXAFS) confirmed this trend and points to a decrease in phenolic moieties in the supernatant and to an eventual increase in phenolic moieties on the surface. Time-resolved luminescence spectroscopy (TRLS) of Eu(III) as luminescent probe showed a decrease in the ratio between the 5D0?7F2 and 5D0?7F1 transitions for the fractionated organic matter (OM) that is thought to be associated with a lower energy transfer from the OM to Eu(III) due to the loss of polar aromatics. These modifications in the supernatant are a hint for the modification of sorbed humic extracts on the surface.

  3. Hydrology, vegetation, and soils of riverine and tidal floodplain forests of the lower Suwannee River, Florida, and potential impacts of flow reductions

    Science.gov (United States)

    Light, Helen M.; Darst, Melanie R.; Lewis, Lori J.; Howell, David A.

    2002-01-01

    A study relating hydrologic conditions, soils, and vegetation of floodplain forests to river flow was conducted in the lower Suwannee River, Florida, from 1996 to 2000. The study was done by the U.S. Geological Survey in cooperation with the Suwannee River Water Management District to help determine the minimum flows and levels required for wetlands protection. The study area included forests within the 10-year floodplain of the Suwannee River from its confluence with the Santa Fe River to the tree line (lower limit of forests) near the Gulf of Mexico, and covered 18,600 hectares (ha) of forests, 75 percent of which were wetlands and 25 percent uplands. The floodplain was divided into three reaches, riverine, upper tidal, and lower tidal, based on changes in hydrology, vegetation, and soils with proximity to the coast. The Suwannee River is the second largest river in Florida in terms of average discharge. Median flow at the confluence of the Suwannee and Santa Fe Rivers is approximately 181 cubic meters per second (m3/s) or 6,480 cubic feet per second (ft3/s) (1933-99). At the upper end of the riverine reach, river stages are unaffected by tides and have a typical annual range of 4.1 meters (m). Tides affect river stages at low and medium flows in the upper tidal reach, and at all flows in the lower tidal reach. Median tidal range at the mouth of the Suwannee River is about 1 m. Salinity of river water in the lower tidal reach increases with decreasing flow and proximity to the Gulf of Mexico. Vertically averaged salinity in the river near the tree line is typically about 5 parts per thousand at medium flow. Land-surface elevation and topographic relief in the floodplain decrease with proximity to the coast. Elevations range from 4.1 to 7.3 m above sea level at the most upstream riverine transect and from 0.3 to 1.3 m above sea level on lower tidal transects. Surface soils in the riverine reach are predominantly mineral and dry soon after floods recede except in

  4. Simultaneous determination of speciation parameters of Cu, Pb, Cd and Zn in model solutions of Suwannee River fulvic acid by pseudopolarography

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Parthasarathi; Fasfous, Ismail I.; Chakrabarti, Chuni L. [Carleton University, Ottawa-Carleton Chemistry Institute, Department of Chemistry, Ottawa, ON (Canada); Murimboh, John [Acadia University, Department of Chemistry, Wolfville, NS (Canada)

    2007-05-15

    There is a growing awareness of the importance of quantitative determinations of speciation parameters of the trace metals Cu, Zn, Cd and Pb in aqueous samples containing chemically heterogeneous humic substances, especially when they are present together, interacting with one another and competing for specific binding sites of the humic substances. Such determinations require fundamental knowledge and understanding of these complex interactions, gained through basic laboratory-based studies of well-characterized humic substances in model solutions. Since the chemical heterogeneity of humic substances plays an important role in the thermodynamics (stability) and kinetics (lability) of trace metal competition for humic substances, a metal speciation technique such as pseudopolarography that can reveal the special, distinctive nature of metal complexation is required, and it was therefore used in this study. A comparison of the heterogeneity parameters ({gamma}) for Zn(II), Cd(II), Pb(II) and Cu(II) complexes in model solutions of Suwannee River fulvic acid (SRFA) shows that {gamma}{sub Cd}>{gamma}{sub Zn}>{gamma}{sub Pb}>{gamma}{sub Cu}, suggesting that SRFA behaves as a relatively homogeneous complexant for Zn(II) and Cd(II), whereas it behaves as a relatively heterogeneous complexant for Pb(II) and an even more heterogeneous complexant for Cu(II) under the experimental conditions used. The order of values of logK{sup *} (from the differential equilibrium function, DEF) for the trace metals at pH 5.0 follow the sequence: logK{sup *}{sub Cu}>logK{sup *}{sub Pb}>logK{sup *}{sub Zn}>logK{sup *}{sub Cd} These results are in good agreement with the literature values. The results of this work suggest the possibility of simultaneously determining several metals in a sample in a single experiment, and hence in a shorter time than required for multiple experiments. (orig.)

  5. A Centennial Tribute, 1906-2006: History of U.S. Geological Survey Streamgaging Activities for the Suwannee River at White Springs, Florida

    Science.gov (United States)

    Verdi, Richard Jay; Tomlinson, Stewart A.

    2009-01-01

    For centuries, the banks of the Suwannee River at White Springs were considered a sacred ground where people sought refuge in its 'healing waters'. Many believed that the mineral-enriched waters cured illnesses. The U.S. Geological Survey began continuous streamgaging activities at White Springs, Florida, in 1906 after an increase in congressional appropriations and rapid town development due to growing tourism and residential population. In 1906, streamgage data was a once-per-day gage reading that were handwritten in a water-level booklet by a local observer with discharge measurements taken every 6 to 8 weeks by a hydrographer. In 2006, real-time data were recorded at 1-hour increments and transmitted to U.S. Geological Survey computer networks using the Geostationary Operational Environmental Satellite, thus enabling the general public to access readings within minutes of the actual measurement. Additional data and measurements are taken and made available for high or low flows that occur during significant floods and droughts. The gage at White Springs has recorded several historic hydrologic events that affected the Suwannee River and surrounding areas. Major droughts include those during 1931-35, 1949-57, and 1998-2002. Severe floods occurred in 1948, 1973, and 2004. On April 10, 1973, the discharge was 38,100 cubic feet per second, which is the highest recorded discharge for the period of record. A flood of this magnitude is expected at a recurrence interval of about once every 200 to 500 years.

  6. Alternating current anodic stripping voltammetry in the study of cadmium complexation by a reference Suwannee river fulvic acid: a model case with strong electrode adsorption and weak binding

    Energy Technology Data Exchange (ETDEWEB)

    Garrigosa, Anna M.; Arino, Cristina; Diaz-Cruz, Jose M.; Esteban, Miquel [Universitat de Barcelona, Departament de Quimica Analitica, Barcelona (Spain)

    2008-01-15

    The possibilities of anodic stripping voltammetry (ASV) using an alternating current (AC) scan in the stripping step have been checked through the study of the complexation of cadmium by Suwannee river fulvic acid (SRFA), a reference fulvic acid from the International Humic Substances Society. Because of the strong electrode adsorption of SRFA, AC mode appears to be a good approach to the study when proper selection of the phase angle is made. The goodness of AC mode in ASV has been demonstrated, and the complexation constant of 3.71 {+-} 0.04 determined is in good agreement with the value of the constant obtained by the reference technique of reverse pulse polarography. Some particularities of SRFA have been observed, among them its homofunctional and strongly heterogeneous behaviour in cadmium complexation and the impossibility of avoiding electrode adsorption problems in ASV measurements at very low metal concentrations. (orig.)

  7. Alternating current anodic stripping voltammetry in the study of cadmium complexation by a reference Suwannee river fulvic acid: a model case with strong electrode adsorption and weak binding.

    Science.gov (United States)

    Garrigosa, Anna Maria; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

    2008-01-01

    The possibilities of anodic stripping voltammetry (ASV) using an alternating current (AC) scan in the stripping step have been checked through the study of the complexation of cadmium by Suwannee river fulvic acid (SRFA), a reference fulvic acid from the International Humic Substances Society. Because of the strong electrode adsorption of SRFA, AC mode appears to be a good approach to the study when proper selection of the phase angle is made. The goodness of AC mode in ASV has been demonstrated, and the complexation constant of 3.71 +/- 0.04 determined is in good agreement with the value of the constant obtained by the reference technique of reverse pulse polarography. Some particularities of SRFA have been observed, among them its homofunctional and strongly heterogeneous behaviour in cadmium complexation and the impossibility of avoiding electrode adsorption problems in ASV measurements at very low metal concentrations. Figure DP anodic stripping and AC anodic stripping voltammograms at -12 degrees and -65 degrees during the titration of a 10(-7) mol L(-1) Cd(II) solution with SRFA at pH 7.5 in 0.05 L(-1) Tris.

  8. Preparative free-flow electrophoretic offline ESI-Fourier transform ion cyclotron resonance/MS analysis of Suwannee River fulvic acid.

    Science.gov (United States)

    Gaspar, Andras; Harir, Mourad; Hertkorn, Norbert; Schmitt-Kopplin, Philippe

    2010-06-01

    Free-flow electrophoresis (FFE), a preparative free zone electrophoretic method, was used offline in conjunction with ultrahigh-resolution FT/ion cyclotron resonance -MS to resolve the complexity of Suwannee River fulvic acid (SRFA). Before MS, the FFE separation conditions and the compatibility with ESI were optimized. The constituents in SRFA were effectively separated based on their charge states and sizes. The obtained mass spectra were compared by means of van Krevelen diagrams and the calculated aromaticity indices of the individual constituents were used to describe the distribution of aromatic/unsaturated structures across the FFE-fractionated samples. The consolidated number of ions observed within the individual SRFA fractions were much higher than those of the bulk samples alone, demonstrating extensive ion suppression effects in bulk SRFA likely also operating in the analysis of complex biogeochemical mixtures in flow injection mode. The FFE approach allows for producing sizable amounts of sample from dilute solutions, which can be easily fractionated into dozens of individual samples with the possibility of further in-depth characterization.

  9. Fractionation of Suwannee River fulvic acid and Aldrich humic acid on {alpha}-Al{sub 2}O{sub 3}: spectroscopic evidence

    Energy Technology Data Exchange (ETDEWEB)

    Claret, F.; Reiller, P.E. [CEA Saclay, DEN/DANS/DPC/SECR, Lab Speciat Radionucleides et Mol, F-91191 Gif Sur Yvette, (France); Claret, F. [BRGM, Environm and Process Div, F-45060 Orleans, (France); Schaefer, T. [Forschungszentrum Karlsruhe, Inst Nukl Entsorgung INE, D-76021 Karlsruhe, (Germany); Brevet, J. [Univ Evry Val Essonne, Lab Analyse et Environm Biol et Environm, CNRS, UMR 8587, F-91025 Evry, (France)

    2008-07-01

    Sorptive fractionation of Suwannee River Fulvic Acid (SRFA) and Purified Aldrich Humic Acid (PAHA) on {alpha}-Al{sub 2}O{sub 3} at pH 6 was probed in the supernatant using different spectroscopic techniques. Comparison of dissolved organic carbon (DOC) analysis with UV/vis spectrophotometric measurements at 254 nm, including specific UV absorbance (SUVA) calculation, revealed a decrease in chromophoric compounds for the non-sorbed extracts after a 24 h contact time. This fractionation, only observable below a certain ratio between initial number of sites of humic substances and of {alpha}-Al{sub 2}O{sub 3}, seems to indicate a higher fractionation for PAHA. C(1s) near-edge X-ray absorption fine structure spectroscopy (NEXAFS) confirmed this trend and points to a decrease in phenolic moieties in the supernatant and to an eventual increase in phenolic moieties on the surface. Time-resolved luminescence spectroscopy (TRLS) of Eu(III) as luminescent probe showed a decrease in the ratio between the {sup 5}D{sub 0}{yields}{sup 7}F{sub 2} and {sup 5}D{sub 0}{yields}{sup 7}F{sub 1} transitions for the fractionated organic matter (OM) that is thought to be associated with a lower energy transfer from the OM to Eu(III) due to the loss of polar aromatics. These modifications in the supernatant are a hint for the modification of sorbed humic extracts on the surface. (authors)

  10. The influence of natural organic matter and aging on suspension stability in guideline toxicity testing of silver, zinc oxide, and titanium dioxide nanoparticles with Daphnia magna

    DEFF Research Database (Denmark)

    Cupi, Denisa; Hartmann, Nanna Isabella Bloch; Baun, Anders

    2015-01-01

    not decrease toxicity significantly. Conversely, the presence of Suwannee River natural organic matter (NOM; 20mgL-1) completely alleviated Ag ENP toxicity in all testing scenarios and did not aid in stabilizing suspensions. In contrast, addition of Suwannee River NOM stabilized ZnO ENP suspensions and did...... not decrease toxicity. Aging for 48h generated monotonous concentration-response curves in the presence and absence of Suwannee River NOM. At concentrations up to 100mgL-1 TiO2 ENPs did not cause immobilization of D. magna under any of the tested conditions. Presence of Suwannee River NOM caused agglomeration...... in stock suspensions. The authors' results suggest that aging and presence of Suwannee River NOM are important parameters in standard toxicity testing of ENPs, which in some cases may aid in gaining better control over the exposure conditions but in other cases might contribute to agglomeration...

  11. Calcite growth-rate inhibition by fulvic acids isolated from Big Soda Lake, Nevada, USA, The Suwannee River, Georgia, USA and by polycarboxylic acids

    Science.gov (United States)

    Reddy, Michael M.; Leenheer, Jerry

    2011-01-01

    Calcite crystallization rates are characterized using a constant solution composition at 25°C, pH=8.5, and calcite supersaturation (Ω) of 4.5 in the absence and presence of fulvic acids isolated from Big Soda Lake, Nevada (BSLFA), and a fulvic acid from the Suwannee River, Georgia (SRFA). Rates are also measured in the presence and absence of low-molar mass, aliphatic-alicyclic polycarboxylic acids (PCA). BSLFA inhibits calcite crystal-growth rates with increasing BSLFA concentration, suggesting that BSLFA adsorbs at growth sites on the calcite crystal surface. Calcite growth morphology in the presence of BSLFA differed from growth in its absence, supporting an adsorption mechanism of calcite-growth inhibition by BSLFA. Calcite growth-rate inhibition by BSLFA is consistent with a model indicating that polycarboxylic acid molecules present in BSLFA adsorb at growth sites on the calcite crystal surface. In contrast to published results for an unfractionated SRFA, there is dramatic calcite growth inhibition (at a concentration of 1 mg/L) by a SRFA fraction eluted by pH 5 solution from XAD-8 resin, indicating that calcite growth-rate inhibition is related to specific SRFA component fractions. A cyclic PCA, 1, 2, 3, 4, 5, 6-cyclohexane hexacarboxylic acid (CHXHCA) is a strong calcite growth-rate inhibitor at concentrations less than 0.1 mg/L. Two other cyclic PCAs, 1, 1 cyclopentanedicarboxylic acid (CPDCA) and 1, 1 cyclobutanedicarboxylic acid (CBDCA) with the carboxylic acid groups attached to the same ring carbon atom, have no effect on calcite growth rates up to concentrations of 10 mg/L. Organic matter ad-sorbed from the air onto the seed crystals has no effect on the measured calcite crystal-growth rates.

  12. Factors affecting the occurrence of Escherichia coli O157 contamination in irrigation ponds on produce farms in the Suwannee River Watershed.

    Science.gov (United States)

    Gu, Ganyu; Luo, Zhiyao; Cevallos-Cevallos, Juan M; Adams, Paige; Vellidis, George; Wright, Anita; van Bruggen, Ariena H C

    2013-03-01

    Outbreaks of enteritis caused by Escherichia coli O157 associated with fresh produce have resulted in questions about the safety of irrigation water; however, associated risks have not been systematically evaluated. In this study, the occurrence and distribution of the human pathogen E. coli O157 from vegetable irrigation ponds within the Suwannee River Watershed in Georgia were investigated, and the relationship to environmental factors was analyzed. Surface and subsurface water samples were collected monthly from 10 vegetable irrigation ponds from March 2011 to February 2012. Escherichia coli O157 was isolated from enriched filtrates on CHROMagar and sorbitol MacConkey agar media and confirmed by an agglutination test. Presence of virulence genes stx1, stx2 , and eae was tested by polymerase chain reaction. In addition, 27 environmental variables of the sampled ponds were measured. Denaturing gradient gel electrophoresis was conducted for the analysis of bacterial communities in the water samples. Biserial correlation coefficients were calculated to evaluate the log10 colony-forming unit per millilitre correlations between the environmental factors and the occurrence of E. coli O157. Stepwise and canonical discriminant analyses were used to determine the factors that were associated with the presence and absence of E. coli O157 in water samples. All 10 ponds were positive for E. coli O157 some of the time, mainly in summer and fall of 2011. The temporal distribution of this bacterium differed among the 10 ponds. Temperature, rainfall, populations of fecal coliform, and culturable bacteria were positively correlated with the occurrence of E. coli O157 (P pond margins) in periods with relatively high temperatures, suggesting that prevention of runoff may be important to minimize the risk of enteric pathogens in irrigation ponds.

  13. Advanced oxidation treatment and photochemical fate of selected antidepressant pharmaceuticals in solutions of Suwannee River humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Santoke, Hanoz, E-mail: hsantoke@uci.edu [Urban Water Research Center, Department of Civil and Environmental Engineering, University of California, Irvine, Irvine, CA 92697-2175 (United States); Song, Weihua, E-mail: wsong@uci.edu [Urban Water Research Center, Department of Civil and Environmental Engineering, University of California, Irvine, Irvine, CA 92697-2175 (United States); Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433 (China); Cooper, William J., E-mail: wcooper@uci.edu [Urban Water Research Center, Department of Civil and Environmental Engineering, University of California, Irvine, Irvine, CA 92697-2175 (United States); Peake, Barrie M., E-mail: bpeake@chemistry.otago.ac.nz [Chemistry Department, University of Otago, P.O. Box 56, Dunedin 9054 (New Zealand)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer We elucidate the photochemical degradation of three antidepressant pharmaceuticals. Black-Right-Pointing-Pointer Hydroxyl radical is the most significant contributor to the degradation. Black-Right-Pointing-Pointer Excited state dissolved organic matter also plays a significant role for duloxetine. Black-Right-Pointing-Pointer Tentative reaction byproducts are identified. - Abstract: Antidepressant pharmaceuticals have recently been detected at low concentrations in wastewater and surface water. This work reports studies of the direct and indirect photochemical fate and treatment by advanced oxidation of three antidepressant compounds (duloxetine, venlafaxine and bupropion) in solutions of humic acid in order to elucidate their behavior in the natural environment prior to reaching a water treatment facility and potentially entering a potable water supply. Humic acid solution was prepared by adding to distilled water a known amount of organic matter as a photosensitizer. All three antidepressants react very rapidly with hydroxyl radicals ({center_dot}OH) and hydrated electrons (e{sup -}{sub aq}) with rate constants of {approx}10{sup 8} to 10{sup 10} M{sup -1} s{sup -1}, but significantly slower with singlet oxygen ({sup 1}{Delta}O{sub 2}) ({approx}10{sup 3} to 10{sup 5} M{sup -1} s{sup -1}). The steady-state concentrations of {center_dot}OH and {sup 1}{Delta}O{sub 2}, in a sample of humic acid solution were measured and used with the second order rate constants to show that the hydroxyl radical was an order of magnitude more effective than the singlet oxygen in the solar-induced photochemical degradation of the antidepressants. Excited state dissolved organic matter also accounted for a substantial portion of degradation of duloxetine, decreasing its half-life by 27% under solar irradiation. Several reaction pathways and by-products arising from the photodegradation were identified using gamma-irradiation followed by LC

  14. Rivers: Nature's Wondrous Waterways.

    Science.gov (United States)

    Harrison, David L.

    Rivers play a vital role in the life of the planet. They provide water for wildlife, plant life, and people, and they help to fertilize fields where corn and other crops grow. But how were these rivers made? This children's book takes readers/students on a journey down a river from its source at the top of a mountain to its mouth where it meets…

  15. Natural transformation in river epilithon.

    OpenAIRE

    Williams, H. G.; Day, M.J.; Fry, J. C.; Stewart, G. J.

    1996-01-01

    Natural transformation was demonstrated in unenclosed experiments incubated in river epilithon. Strains of Acinetobacter calcoaceticus were transformed to prototrophy by either free DNA (lysates) or live donor cells. The sources of transforming DNA and recipient culture were immobilized on filters, secured to stones, and incubated midstream in the river. The transfer frequency generally increased with temperature. No transfer was detected in the river Taff below 10 degrees C. The age of the r...

  16. Study of iron and aluminum binding to Suwannee River fulvic acid using absorbance and fluorescence spectroscopy: comparison of data interpretation based on NICA-Donnan and Stockholm humic models.

    Science.gov (United States)

    Yan, Mingquan; Benedetti, Marc F; Korshin, Gregory V

    2013-09-15

    This study examined the evolution of absorbance and fluorescence spectra of standard Suwannee River fulvic acid (SRFA) induced by its interactions with iron and aluminum. The results show that changes of SRFA absorbance are associated with a consistent response of the carboxylic and phenolic functional groups to iron and aluminum forming bonds with these groups, and their deprotonation induced by such binding. The observed changes of SRFA absorbance were quantified via the use of DSlope325-375 parameter that determines the behavior of the slope of logarithms of SRFA absorbance in the range of wavelengths 325-375 nm in the presence of varying concentrations of iron or aluminum. DSlope325-375 values were correlated linearly with the concentration of SRFA-bound iron and aluminum determined using either NICA-Donnan or Stockholm Humic Model (SHM) but the correlation was stronger for the former model (R(2) > 0.98). The slopes of these correlations were similar for both iron and aluminum concentrations <10.0 μM and at a wide pH range. Fluorescence of SRFA was responsive to metal binding but it changed less consistently in the presence of the examined metals, especially in the case of aluminum. The combination of these techniques can help explore in more detail manifestations of DOM site specificity at realistically low concentrations of DOM and metal ions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Fluorescence characterization of the interaction Suwannee river fulvic acid with the herbicide dichlorprop (2-(2,4-dichlorophenoxy)propionic acid) in the absence and presence of aluminum or erbium.

    Science.gov (United States)

    Elkins, Kelly M; Dickerson, Matthew A; Traudt, Elizabeth M

    2011-11-01

    This study uses fluorescence spectroscopy to better understand the role of environmental metal ions in the interaction of charged herbicides with biochemical degradation product Suwannee River fulvic acid (SRFA). The interactions between the widely-used herbicide dichlorprop (2-(2,4-dichlorophenoxy)propionic acid) (DCPPA) with Al(3+) and the comparative metal Er(3+) were probed at pH 4.0. Fluorescence experiments on binary solutions at pH 4.0 clearly indicated that Al(3+) and Er(3+) strongly interact with both SRFA and DCPPA alone in solution as demonstrated by fluorescence quenching with DCPPA and enhancement with SRFA by Al(3+) and fluorescence quenching of both SRFA and DCPPA fluorescence by Er(3+). Titrating Al(3+) or Er(3+) to SRFA-DCPPA quenched SRFA fluorescence as compared to the SRFA-metal ion binary complexes. Formation constants were determined using the Ryan-Weber model for the titration data. The DCPPA fluorescence results strongly support the formation of DCPPA-Al(3+) and DCPPA-Er(3+) complexes at pH values above the pK(a) (3.0) of DCPPA. Excitation and emission data obtained on ternary solutions of SRFA-Al(3+)-DCPPA and SRFA-Er(3+)-DCPPA complexes at pH 4.0 suggest that at this pH where the predominant DCPPA species is negatively-charged, Al(3+) and Er(3+) metal ions may function to "bridge" negatively-charged fulvic acids to negatively-charged pesticides. Fluorescence data collected on UV-irradiated ternary complexes indicate that both metals can also bridge DCPPA interactions with SRFA under those conditions. The results of our studies suggest that creation of a herbicide-free boundary corridor is recommended near mines and runoff areas with metal ions in surface waters to control possible complexation among fulvic acids, DCPPA and metal ions that maintains these molecules in a bioavailable state to plants and animals. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. A Profile of Suwannee County, Florida.

    Science.gov (United States)

    Beaulieu, Lionel J.

    Agriculture and the railroad were significant forces in the development of Suwannee County, Florida, formally created in 1858 but explored and settled beginning some 300 years earlier. Lumber and cotton caused an early 20th century boom in the county which soon saw the negative effects of both industries. The introduction of tobacco in the late…

  19. Landscape Evolution Modelling of naturally dammed rivers

    NARCIS (Netherlands)

    van Gorp, Wouter; Temme, Arnaud J. A. M.; Baartman, Jantiene E. M.; Schoorl, Jeroen M.

    2014-01-01

    Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and

  20. Defining winter trophic habitat of juvenile Gulf Sturgeon in the Suwannee and Apalachicola rivermouth estuaries, acoustic telemetry investigations

    Science.gov (United States)

    Sulak, K.J.; Randall, M.T.; Edwards, R.E.; Summers, T.M.; Luke, K.E.; Smith, W.T.; Norem, A.D.; Harden, William M.; Lukens, R.H.; Parauka, F.; Bolden, S.; Lehnert, R.

    2009-01-01

    Three automated listening post-telemetry studies were undertaken in the Suwannee and Apalachicola estuaries to gain knowledge of habitats use by juvenile Gulf Sturgeons (Acipenser oxyrinchus desotoi) on winter feeding grounds. A simple and reliable method for external attachment of small acoustic tags to the dorsal fin base was developed using shrink-tubing. Suspending receivers on masts below anchored buoys improved reception and facilitated downloading; a detection range of 500–2500 m was realized. In the Apalachicola estuary, juvenile GS stayed in shallow water (McKenzie et al., 2001; Singer and Ballantyne, 2002) for short periods in deep offshore waters seems adaptively advantageous relative to the risk of cold-event mortality in shallow inshore waters of lower salinity. Thus, while juveniles can tolerate high salinities for days to weeks to escape cold events, they appear to make only infrequent use of open polyhaline waters. Throughout the winter foraging period, juvenile GS stayed primarily within the core area of Suwannee River mouth influence, extending about 12 km north and south of the river mouth, and somewhat seaward of Suwannee Reef (< 5 km offshore). None were detected departing the core area past either of the northern or southern acoustic gates, located 66 and 52 km distant from the river mouth, respectively.

  1. River pollution caused by natural stone industry

    Science.gov (United States)

    Oktriani, Ani; Darmajanti, Linda; Soesilo, Tri Edhi Budhi

    2017-03-01

    The natural stone industry is classified as small industry. Current wastewater treatment still causes pollution in the river. This thesis aims to analyze the performance of wastewater treatment in natural stones industry. The data was collected from water quality test (parameters: temperature, pH, DO, and TSS). The wastewater treatment performance was in a slightly higher position compared to the 2nd class quality standards of Government Regulation No. 82/2001. The parameter that exceeded quality standards was the concentration of TSS, which was up to 240.8 mg/l. The high concentration of TSS was affected by the absence of sludge management schedule, which resulted in non-optimal precipitation. Besides that, the design of sedimentation basin was still not adapted with wastewater debit. Referring to the results, this study suggests the government of Cirebon District to provide wastewater treatment development through the village staff. Furthermore, the government also needs to give strict punishment to business owner who does not treat waste correctly and does not have a business license. Moreover, the sale value of sludge as byproduct of wastewater treatment needs to be increased.

  2. Natural Setting and Vegetation of the Florida Panhandle. An Account of the Environments and Plant Communities of Northern Florida, West of the Suwannee River.

    Science.gov (United States)

    1986-01-01

    which prohibited grazing on open range. Thereafter pastures were fenced and improved by the planting of bahia grass and other exotics. Many forested...Man certainly includes peoples of other continents who immigrated to North America, beginning with the Spanish in the 1500’s. Some authors consider...populations are augmented beyond the carrying capacity of the habitat because of immigrations from surrounding regions. 226 - . Referencespp Delcourt, H. R

  3. Probabilities of Natural Events Occurring at Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J.C.

    2001-07-17

    This report documents the comprehensive evaluation of probability models of natural events which are applicable to Savannah River Plant. The probability curves selected for these natural events are recommended to be used by all SRP/SRL safety analysts. This will ensure a consistency in analysis methodology for postulated SAR incidents involving natural phenomena.

  4. Evidence of natural reproduction by Muskellunge in middle Tennessee rivers

    Science.gov (United States)

    Warren, Lila H.; Bettoli, Phillip William

    2014-01-01

    Native Esox masquinongy (Muskellunge) in the Cumberland River drainage, TN, were nearly extirpated in the 1970s due to decades of over-fishing and habitat degradation from coal mining, logging, and other land-use practices. In an effort to preserve the species in that drainage, a stocking program began in 1976 in the upper Caney Fork River system in middle Tennessee where Muskellunge were not native. A trophy Muskellunge fishery eventually developed, but it was unknown whether Muskellunge were reproducing in the upper Caney Fork River system or whether the fishery was wholly dependent on the stocking program. To establish evidence of natural reproduction, we used seines, backpack electrofishing, and boat electrofishing gear in 2012 to find age-0 Muskellunge in the upper Caney Fork River system. Natural reproduction of Muskellunge was documented in the mainstem Caney Fork River above Great Falls Dam and in 3 of its 4 major tributaries. Seventeen age-0 Muskellunge were collected and one other was observed, but not handled. Age-0 Muskellunge grew rapidly (1.80–2.34 mm/day), and the largest fish collected during the study reached a total length of 399 mm by 9 October 2012. A cessation of stocking for several years coupled with routine monitoring could reveal whether natural recruitment is sufficient to sustain the fishery.

  5. Transport distance of invertebrate environmental DNA in a natural river.

    Directory of Open Access Journals (Sweden)

    Kristy Deiner

    Full Text Available Environmental DNA (eDNA monitoring is a novel molecular technique to detect species in natural habitats. Many eDNA studies in aquatic systems have focused on lake or ponds, and/or on large vertebrate species, but applications to invertebrates in river systems are emerging. A challenge in applying eDNA monitoring in flowing waters is that a species' DNA can be transported downstream. Whether and how far eDNA can be detected due to downstream transport remains largely unknown. In this study we tested for downstream detection of eDNA for two invertebrate species, Daphnia longispina and Unio tumidus, which are lake dwelling species in our study area. The goal was to determine how far away from the source population in a lake their eDNA could be detected in an outflowing river. We sampled water from eleven river sites in regular intervals up to 12.3 km downstream of the lake, developed new eDNA probes for both species, and used a standard PCR and Sanger sequencing detection method to confirm presence of each species' eDNA in the river. We detected D. longispina at all locations and across two time points (July and October; whereas with U. tumidus, we observed a decreased detection rate and did not detect its eDNA after 9.1 km. We also observed a difference in detection for this species at different times of year. The observed movement of eDNA from the source amounting to nearly 10 km for these species indicates that the resolution of an eDNA sample can be large in river systems. Our results indicate that there may be species' specific transport distances for eDNA and demonstrate for the first time that invertebrate eDNA can persist over relatively large distances in a natural river system.

  6. Transport distance of invertebrate environmental DNA in a natural river.

    Science.gov (United States)

    Deiner, Kristy; Altermatt, Florian

    2014-01-01

    Environmental DNA (eDNA) monitoring is a novel molecular technique to detect species in natural habitats. Many eDNA studies in aquatic systems have focused on lake or ponds, and/or on large vertebrate species, but applications to invertebrates in river systems are emerging. A challenge in applying eDNA monitoring in flowing waters is that a species' DNA can be transported downstream. Whether and how far eDNA can be detected due to downstream transport remains largely unknown. In this study we tested for downstream detection of eDNA for two invertebrate species, Daphnia longispina and Unio tumidus, which are lake dwelling species in our study area. The goal was to determine how far away from the source population in a lake their eDNA could be detected in an outflowing river. We sampled water from eleven river sites in regular intervals up to 12.3 km downstream of the lake, developed new eDNA probes for both species, and used a standard PCR and Sanger sequencing detection method to confirm presence of each species' eDNA in the river. We detected D. longispina at all locations and across two time points (July and October); whereas with U. tumidus, we observed a decreased detection rate and did not detect its eDNA after 9.1 km. We also observed a difference in detection for this species at different times of year. The observed movement of eDNA from the source amounting to nearly 10 km for these species indicates that the resolution of an eDNA sample can be large in river systems. Our results indicate that there may be species' specific transport distances for eDNA and demonstrate for the first time that invertebrate eDNA can persist over relatively large distances in a natural river system.

  7. Natural radioactivity in stream sediments of Oltet River, Romania

    Science.gov (United States)

    Ion, Adriana

    2017-04-01

    The concentration of naturally occurring radionuclides (U-238, Th-232 and K-40) in stream sediments of the Oltet River was measured in order to establish the primary sources of radionuclides, the transport pathways and the geochemical factors favouring their mobilisation and concentration in the existing geological context. The Oltet River has a length of 185 Km and crosses the southern central part of the country, being the right tributary of the Olt River. The range in elevation of the watercourse varies between 1963 m in the springs area (Parîng Mountains) and 200 m at the confluence with the Olt River, whereas the relief of the Oltet Basin has a varied character, manifested by the presence of diverse forms of relief, starting with major mountainous heights and ending with low-lying plains regions. In cross section from North to South, the Olteț River cuts metamorphic rocks (schist, gneisses, quartzite, marble, mica-schist's), magmatic rocks (granite and granitoid massifs - intruded by veins of microgranite, aplite, pegmatite and lamprophyre) and limestone, followed by deposits composed of clays, marls, sands and gravels, that are characterized by the presence of lignite seams. 44 stream sediment samples were collected in summer of 2016 from sampling points distributed along the river with an equidistance of about 4 - 5 km. The activity concentrations of the U-238, Th-232 and K-40 were measured by gamma ray spectrometry using HPGe detector (ORTEC) with 26% relative efficiency in multilayer shielding. The reference materials used were IAEA - RGK-1 and IAEA - 314. Analysis was performed on the geochemical process the amounts of thorium and potassium released are modest, leaching of uranium being the dominant feature (uranyl ion). The downstream lignite seams are the secondary geochemical barriers in accumulation of uranium; the radiometric data obtained for stream sediments emphasize this enrichment.

  8. Sex in the Suwannee, the secretive love life of Gulf Sturgeons

    Science.gov (United States)

    Sulak, Kenneth J.

    2014-01-01

    Mid-February in the Gulf of Mexico and a timeless ritual is about to repeat itself for perhaps the millionth time. Some mysterious signal, possibly increasing day length, flips an internal switch, feeding stops, and the homeward migration begins for the Gulf Sturgeon (Acipenser oxyrinchus desotoi). From far flung places along the Gulf Coast, Gulf Sturgeons start heading back to their natal rivers – they know the way instinctively. Maybe they seek out the special chemical taste of their home river, imprinted at hatching. Or perhaps the ultrasensitive electric organs decorating the underside of the snout can follow the map of the earth’s magnetic field. Either way, time to make a beeline for the welcoming waters of the Suwannee River, or maybe the Apalachicola, Choctawhatchee, or one of four other spawning rivers. Some of the adults are on a special mission – time to spawn, time to perpetuate the species. Mature males form the first wave in this homebound marathon, eager to get to the spawning grounds, eager to be the first to greet ready females with a series of sharp clicking sounds. Only spawning once each three years, females laden with large black eggs demure, taking their time, arriving in mid to late March, a month behind the early males. But most sturgeons, juveniles and immature adults not ready to spawn, are simply heading home. Not prompted by the spawning urge, they are just following the ancient annual cycle of intense winter feeding in the Gulf, followed by several months of fasting and R&R in the river.

  9. Water Resource Inventory and Assessment: Lower Suwannee National Wildlife Refuge Dixie and Levy Counties, Florida

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Water Resource Inventory and Assessment (WRIA) report for Lower Suwannee National Wildlife Refuge describes current hydrologic information relevant to the...

  10. Adsorption of zinc on natural sediment of Tafna River (Algeria)

    Energy Technology Data Exchange (ETDEWEB)

    Dali-youcef, N. [Universite des Sciences et Technologies de Lille, Laboratoire de Chimie Analytique et Marine, UMR CNRS 8110 PBDS and FR 1818, Bat. C8 2eme etage, 59655 Villeneuve d' Ascq Cedex (France)]. E-mail: nacera.dali@caramail.com; Ouddane, B. [Universite des Sciences et Technologies de Lille, Laboratoire de Chimie Analytique et Marine, UMR CNRS 8110 PBDS and FR 1818, Bat. C8 2eme etage, 59655 Villeneuve d' Ascq Cedex (France); Derriche, Z. [Universite des Sciences et Technologies de d' Oran, Laboratoire de Physico-chimie des Materiaux, El M' Naouar, BP 1505, 31000 Oran (Algeria)

    2006-10-11

    The environmental impact of metal additions to sediment depends on its sorption ability. The paper presents a study of zinc adsorption using the experiment data on natural sediment of Tafna River in northwest of Algeria. The effect of various operating variables, namely initial concentration, mass of sediment, and contact time, have been studied. The optimum contact time needed to reach equilibrium is of the order of 30 min and is independent of initial concentration and mass of zinc ions. The extent of adsorption increases with increase of concentration, and with decrease of adsorbent mass. The content of carbonate in sediment increases the adsorption indicating the active support material towards zinc ions. A batch sorption model, which assumes the pseudo-second-order mechanism, is developed to predict the rate constant of the sorption, the equilibrium sorption capacity and the initial sorption rate with the effect of initial zinc ion concentration and sediment dose. Various thermodynamic parameters, such as {delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o}, have been calculated. The thermodynamics of zinc ion/sediment system indicates spontaneous, endothermic and randomness nature of the process.

  11. Forest types of the "Argentino River Valley" Natural Reserve

    Directory of Open Access Journals (Sweden)

    Bagnato S

    2008-09-01

    Full Text Available Forest classification is a fundamental target for understanding forest stand dynamics and for sustainable management strategy applications. In this paper the methodological approach of forest types, already used in other Italians region, was applied for the classification of the RNO "Argentino River Valley" (southern Apennine, Italy. This study has been organized in 4 steps: 1 bibliographic analysis and collection of the acquired knowledge; 2 preliminary verification of forest types in the field; 3 description of the different units; 4 final validation of typological units. Using this approach we have characterized 9 categories and 12 forest types units. The description of each units has been filed as cards, where information of different nature is summarized and related to the organization of the typological units, to its location, to the description of the qualitative indicators (disturbances, cohort, mortality, natural dynamic tendencies, SDT, CWD etc. and quantitative indicators (dbh, average height, current annual increment, etc., to the functioning and the current management. For a better understanding of types functioning, "sylvology models" based on the "Spatial Pattern of Relative Collective Interaction" (PSICR and on the principal characteristics influencing and characterizing forest stand dynamics (availability of resources, type and frequency of disturbances, stand development, etc. have been singled out and proposed. The "forest types map" and other maps useful for the management of forest resources have been obtained. Moreover, data collected did allow to formulate several hypotheses on sustainable management.

  12. The Integrated System of Phytodepuration of Sile River Natural Park.

    Science.gov (United States)

    Petroselli, Andrea; Giannotti, Maurizio; Arcangeletti, Ettore; Palomba, Francesca; Marras, Tatiana

    2015-01-01

    The water conservation topic is likely to become increasingly important and alternative water resources employment should be considered as one possible response to the challenges of fresh water demand and environmental protection; among alternative water sources, municipal wastewaters represent one of the most profitable source but in order to reuse them they need adequate and advanced depuration techniques, such as the use of Integrated System of Phytodepuration (ISP). Across a 3-year sampling period, the performances of an ISP within the Natural Park of the Sile River in the Northern Italy were evaluated, analyzing raw wastewater and final effluent characteristics according to the recommendations of European and Italian legislation. The investigated ISP represents one of the first attempts designed in Italy to improve the efficiency of an existing wastewater treatment plant, able to serve 8000 equivalent inhabitants. The results obtained during the 3 years of analysis show that the designed ISP is characterized by a general efficiency value higher than 87% for TSS removal, 79% for TN, 91% for BOD5 and 86% for COD; moreover the ISP final effluent is characterized by a quality not only suited for release into surface waters but also for irrigation.

  13. Small is beautiful: Upscaling from microscale laminar to natural turbulent rivers

    OpenAIRE

    Malverti, L.; Lajeunesse, E.; Métivier, F.

    2008-01-01

    International audience; [1] The use of microscale experimental rivers (with flow depths of the order of a few millimeters) to investigate natural processes such as alluvial fans dynamics, knickpoints migration, and channel morphologies, such as meandering and braiding has become increasingly popular in recent years. This raises the need to address the issue of how to extrapolate results from the experimental microscale at which flow is laminar to the scale of natural turbulent rivers. We addr...

  14. Genetic characterization of naturally spawned Snake River fall-run Chinook salmon

    Science.gov (United States)

    Marshall, A.R.; Blankenship, H.L.; Connor, W.P.

    1999-01-01

    We sampled juvenile Snake River chinook salmon Oncorhynchus tshawytscha to genetically characterize the endangered Snake River fall-run population. Juveniles from fall and spring–summer lineages coexisted in our sampling areas but were differentiated by large allozyme allele frequency differences. We sorted juveniles by multilocus genotypes into putative fall and spring lineage subsamples and determined lineage composition using maximum likelihood estimation methods. Paired sMEP-1* and PGK-2* genotypes—encoding malic enzyme (NADP+) and phosphoglycerate kinase, respectively—were very effective for sorting juveniles by lineage, and subsamples estimated to be 100% fall lineage were obtained in four annual samples. We examined genetic relationships of these fall lineage juveniles with adjacent populations from the Columbia River and from Lyons Ferry Hatchery, which was established to perpetuate the Snake River fall-run population. Our samples of naturally produced Snake River fall lineage juveniles were most closely aligned with Lyons Ferry Hatchery samples. Although fall-run strays of Columbia River hatchery origin found on spawning grounds threaten the genetic integrity of the Snake River population, juvenile samples (a) showed distinctive patterns of allelic diversity, (b) were differentiated from Columbia River populations, and (c) substantiate earlier conclusions that this population is an important genetic resource. This first characterization of naturally produced Snake River fall chinook salmon provides a baseline for monitoring and recovery planning.

  15. Reconstruction natural flow in a regulated system, the Murrumbidgee River, Australia, using time series analysis

    Science.gov (United States)

    Wen, Li

    2009-01-01

    SummaryIn the area of floodplain restoration, river managers and ecologists emphasise the need to partially or fully restore a range of natural variations to flow regimes. The most common approach to investigate the natural flow has been the use of hydrological models. This study illustrates that multivariate time series analysis is a valid alternative. Thirty years of pre-regulation time series of monthly discharge, rainfall, and maximum temperature in Murrumbidgee Catchment are used to build the regressive models which represent the natural state of catchment hydrology. The models successfully arrest the dynamic behaviour of river discharges for both upstream and downstream stations; and demonstrate the lagged correlations between climatic variables and river discharges. Furthermore, the models also indicate there are strong autocorrelation in river discharge time series. The correlations between lagged climatic variables and river discharge and autocorrelations can be used to better understand the hydrologic response to climatic forcings. To demonstrate the application of this new approach, the fitted models are using to forecast the monthly river discharges from 1921 to 2007 at Balranald, Hay, and Wagga Wagga. The results indicate that river flows were increased significantly upstream (Wagga Wagga) on an annual base although the winter/spring flows were reduced. In addition, the peak flows are shifted from winter to summer, especially during drought periods. Conversely, for the downstream stations (Hay and Balranald), the river discharges are significantly reduced for all months; and the flow seasonality is close to the natural pattern. The results are generally consistent with the integrated quality and quantity model (IQQM) approach. The method to reconstruct river flow time series illustrated in the study can be adopted to evaluate the effects of river management plans and policies.

  16. Hydrological classification of natural flow regimes to support environmental flow assessments in intensively regulated Mediterranean rivers, Segura River Basin (Spain).

    Science.gov (United States)

    Belmar, Oscar; Velasco, Josefa; Martinez-Capel, Francisco

    2011-05-01

    Hydrological classification constitutes the first step of a new holistic framework for developing regional environmental flow criteria: the "Ecological Limits of Hydrologic Alteration (ELOHA)". The aim of this study was to develop a classification for 390 stream sections of the Segura River Basin based on 73 hydrological indices that characterize their natural flow regimes. The hydrological indices were calculated with 25 years of natural monthly flows (1980/81-2005/06) derived from a rainfall-runoff model developed by the Spanish Ministry of Environment and Public Works. These indices included, at a monthly or annual basis, measures of duration of droughts and central tendency and dispersion of flow magnitude (average, low and high flow conditions). Principal Component Analysis (PCA) indicated high redundancy among most hydrological indices, as well as two gradients: flow magnitude for mainstream rivers and temporal variability for tributary streams. A classification with eight flow-regime classes was chosen as the most easily interpretable in the Segura River Basin, which was supported by ANOSIM analyses. These classes can be simplified in 4 broader groups, with different seasonal discharge pattern: large rivers, perennial stable streams, perennial seasonal streams and intermittent and ephemeral streams. They showed a high degree of spatial cohesion, following a gradient associated with climatic aridity from NW to SE, and were well defined in terms of the fundamental variables in Mediterranean streams: magnitude and temporal variability of flows. Therefore, this classification is a fundamental tool to support water management and planning in the Segura River Basin. Future research will allow us to study the flow alteration-ecological response relationship for each river type, and set the basis to design scientifically credible environmental flows following the ELOHA framework.

  17. Europium (III) and Uranium (VI) complexation by natural organic matter (NOM): Effect of source.

    Science.gov (United States)

    Kautenburger, Ralf; Sander, Jonas M; Hein, Christina

    2017-03-01

    For the safe long-term storage of high-level radioactive waste (HLW), detailed information about geo-chemical behavior of radioactive and toxic metal ions under environmental conditions is important. Natural organic matter (NOM) can play a crucial role in the immobilization or mobilization of these metal ions due to its complexation and colloid formation tendency. In this study, the complexation of europium (as chemical homologue of trivalent actinides such as americium) and uranium (as main component of HLW) by ten humic acids (HA) from different sources and Suwannee NOM river extract has been analyzed. Capillary electrophoresis in combination with inductively coupled plasma mass spectrometry has been used for the evaluation of complex stability constants log β. In order to determine the complex stability constants a conservative single site model was used in this study. In dependence of their source and thus of NOM structure the log β values for the analyzed humic acids are in the range of 6.1-7.0 for Eu(III) and 5.2-6.4 for U(VI) (UO 2 2+ ), respectively. In contrast to the results for HA the used Suwannee river NOM reveals log β values in the range of nearly two orders of magnitude lower (4.6 for Eu 3+ and 4.5 for UO 2 2+ ) under the geochemical conditions applied in this study. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Emergy evaluation of the natural value of water resources in Chinese rivers.

    Science.gov (United States)

    Chen, Dan; Chen, Jing; Luo, Zhaohui; Lv, Zhuwu

    2009-08-01

    Emergy theory and method were used to evaluate the economy of China and the contributions of water resources in Chinese rivers to the real wealth of the Chinese economy. The water cycle and energy conversion were reviewed, and an emergy method for evaluating the natural value of water resources in a river watershed was developed. The indices for China calculated from the emergy evaluation were close to those of developing countries. Despite a small surplus in its balance of payments, China had a net emergy loss from its trade in 2002. The efficiency of Chinese natural resource use was still not high and did not match its economic growth rate. Furthermore, the Chinese economy placed a stress on its ecological environment and natural resources. Several indices of Chinese rivers from the emergy evaluation were close to those of average global river water. The main average indices of Chinese rivers were transformity (4.17 x 10(4) sej/J), emergy per volume (2.05 x 10(11) sej/m(3)), and emdollar per volume (0.06 $/m(3)). The total value of all the rivers' water made up 13.0% of the GDP of China in 2002, and that of water consumption accounted for 2.1%. The value of the water resources in the Haiheluanhe River (11.39 x 10(4) sej/J) was the highest, followed by the Yellow River (10.27 x 10(4) sej/J), while the rivers in Southwest China had the lowest values (2.92 x 10(4) sej/J).

  19. Two Rivers: The Politics of Wild Salmon, Indigenous Rights and Natural Resource Management

    Directory of Open Access Journals (Sweden)

    Benedict J. Colombi

    2013-01-01

    Full Text Available This paper compares two rivers, Tana River in Northern Norway and Columbia River on the northwest coast of the United States of America. Both rivers host indigenous populations, the Sámi and the Nez Perce, whose cultural and material existence depends upon salmon. Because these people live indigenously within highly industrial, postcolonial societies, their lives have been part of larger economic, political and legal structures for substantial periods of time. In these rivers, peoples have been, and are currently dealing with the possibility of salmon extinction. This article is concerned with how such a crisis has been interpreted and acted upon within two nation’s natural-resource management regimes. We observe how the threat of extinction has initiated commotion where nature, economies, legal instruments, politics and science have come into play, in ways that reveal differences in the Norwegian and American constellations of interests and powers, manifested as differences in natural resource management regimes’ hierarchies of positions. The outcome is the protection of different entities, which could be labeled cultural and biological sustainability. In the Columbia River, cultural sustainability was promoted while in the Tana, biological sustainability became prioritized. By way of our comparison we ask if the protection of one kind of sustainability has to be to the detriment of the other.

  20. Preliminary natural resource survey : Carson River Mercury Site, Nevada

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The survey in this report was conducted to determine if natural resources under the trusteeship of Interior have been affected by the release of hazardous substances...

  1. Determination of the Speciation and Bioavailability of Sm to Chlamydomonas reinhardtii in the Presence of Natural Organic Matter.

    Science.gov (United States)

    Rowell, Justine-Anne; Fillion, Marc-Alexandre; Smith, Scott; Wilkinson, Kevin J

    2018-02-03

    As technological interest and environmental emissions of the rare earth elements (REE) increase, it is becoming more important to assess their potential environmental impact. Samarium (Sm) is a lanthanide of intermediate molar mass that is used in numerous high technology applications including wind turbines, solar panels and electric vehicles. The present study relates the speciation of samarium (Sm) determined in the presence of natural organic matter (NOM) to its bioavailability to the unicellular green alga, Chlamydomonas reinhardtii. The free ion concentration was determined using a cation exchange resin (IET) in dynamic mode and compared to thermodynamic modelling. Short-term biouptake experiments were performed in the presence of 4 types of NOM: Suwannee River fulvic acids, Pahokee Peat fulvic acids, Suwannee River humic acids and a Luther Marsh dissolved organic matter isolate (90-95% humic acids). The results clearly showed that even a small amount of NOM (0.5 mg C L-1 ) resulted in a significant decrease (10x) in the Sm internalization fluxes. Furthermore, complexation with humic acids (and the corresponding reduction in Sm bioavailability) was stronger than for the fulvic acids. The results showed that the experimentally measured (free) Sm was a better predictor of Sm internalization than either the total concentrations or the free ion concentrations obtained using thermodynamic modelling. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  2. Uranium and thorium series nuclides in river sediments and river water

    Energy Technology Data Exchange (ETDEWEB)

    Scott, M. R.; Salter, P. F

    1980-01-01

    Large volume suspended sediment samples were taken from Rio Grande, Mississippi and Suwannee Rivers. These rivers drain arid, moderate and subtropical regions, respectively. The samples were taken to provide enough material to use for chemical fractionation leaching studies of the relationship between Pu and other nuclides with various components of the sediment. This work is still in progress and is described in detail in a separate section of the progress report.

  3. Nature and the river: a natural resources report of the Chicago and Calumet waterways.

    Science.gov (United States)

    Barbara J Moore; John D. Rogner; Drew Ullberg

    1998-01-01

    In 1992, the National Park Service initiated a project to galvanize local interest in the conservation and use of the Chicago Waterway System. The purpose of this project was to promote local stewardship of the waterway system through the integration of economic development, recreation, and environmental conservation. As a result, the ChicagoRivers Demonstration...

  4. Natural resource management activities at the Savannah River Site. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    This environmental assessment (EA) reviews the environmental consequences of ongoing natural resource management activities on the Savannah River Site (SRS). Appendix A contains the Natural Resources Management Plant (NRMP). While several SRS organizations have primary responsibilities for different elements of the plan, the United States Department of Agriculture (USDA), Forest Service, Savannah River Forest Station (SRFS) is responsible for most elements. Of the river scenarios defined in 1985, the High-Intensity Management alternative established the upper bound of environmental consequences; it represents a more intense level of resource management than that being performed under current resource management activities. This alternative established compliance mechanisms for several natural resource-related requirements and maximum practical timber harvesting. Similarly, the Low-Intensity Management alternative established the lower bound of environmental consequences and represents a less intense level of resource management than that being performed under current resource management activities. This alternative also established compliance mechanisms, but defined a passively managed natural area. The Proposed Action of this EA describes the current level of multiple-natural resource management. This EA reviews the proposed action, and the high and low intensity alternative scenarios.

  5. A prospective monitoring of natural and anthropical fish populations in the basin of the Trotus river

    Directory of Open Access Journals (Sweden)

    URECHE Dorel

    2006-09-01

    Full Text Available As a major part of the Siret river hidrography, though less known ichthyologically, the Trotus has a series of tributaries worth mentioning for their natural sources of water pollution (the Slanic River for sodium chloride, the Tazlau River for potassium chloride and the Tazlaul Sarat for petroleum derivatives as well as for the chemical pollution from the plants in Darmanesti and Onesti. All these in mind the impact of the pollution over the fish fauna of the above mentioned area was determined. The basinal analysis of the ichthyocenosis was performed in three locations the selection of which was based on the particulars of the habitat: upper Trotus free of chemical and urban waste, the Tazlau and middle and downstream Trotus – an area affected by chemical and urban waste upstream Comanesti. A total number of sampling stations was chosen so as to cover all particular fish breeding associations and changes in spreading of the species.

  6. Floodplain of the Orlice River (Eastern Bohemia, Czech Republic: The Natural Centre of Biodiversity

    Directory of Open Access Journals (Sweden)

    Vávra Michal

    2015-12-01

    Full Text Available The article presents the main results of a field research carried out between 2012 and 2014. It is a comparison case study of vegetation diversity of pools and dead-end branches of the Orlice River in Eastern Bohemia, Czech Republic. The actual state of wetland vegetation is being compared to data from literature that is several decades old. Botanical survey was conducted in the study area located between the town of Hradec Králové and parishes of Malšovice, Malšova Lhota a Svinary. The research confirmed that dead-end river branches and oxbow lakes form potential refugia of biodiversity of vascular plants in the landscape context of the river area despite the fact that the River Orlice was fully regulated in the urban area of Hradec Králové and the surrounding parishes in the past. Nevertheless, the river area is of a natural character there and belongs to the Nature Park of Orlice since 1996. The local ecosystems are also a part of the important locality of the River Orlice and Elbe. The total of 449 taxons of vascular plants (on the level of species and sub-species and species rich associations of aquatic and wetland plants were recorded in the study area. Conservation of the water regime in the fluvial landscape and suitable regulation interventions against some spreading invasive species are crucial for the continuing existence of the precious species composition. For this reason the article also includes some management steps.

  7. Assessment of the natural flow regime in a Mediterranean river impacted from irrigated agriculture.

    Science.gov (United States)

    Stefanidis, Konstantinos; Panagopoulos, Yiannis; Psomas, Alexandros; Mimikou, Maria

    2016-12-15

    Over the last few decades, the natural flow regime of most rivers has been significantly altered influencing the ecological integrity and functioning of river ecosystems. Especially in the Mediterranean region, irrigated agriculture is considered one of the most important drivers of hydro-morphological modifications in river systems. In this study we employ the Indicators of Hydrologic Alteration (IHA) methodology for the Pinios River and its tributaries, located in a Mediterranean catchment in central Greece, with the purpose to assess the natural flow regime under a simulated no-agriculture scenario and compare with the current situation. The work is based on the use of the SWAT (Soil Water Assessment Tool) model for the simulation of long time series of daily stream flows, which were analyzed under the actual conditions (baseline), and the hypothetical scenario. The key characteristics of the flow regime projected under each model run were assessed through the implementation of the IHA methodology that utilizes a number of indicators to characterize the intra- and inter-annual variability in the hydrologic conditions. The results of this study revealed that without agricultural activities in the catchment, annual and monthly flows would increase, with significant alterations in the flow characteristics of the winter months, and much smaller in summer. However, the analysis showed that the frequency of droughts and low flow summer events would be smaller. The article provides a comprehensive and easy-to-implement methodology that can facilitate the impact assessment of agricultural human activities on river flow variability under the typical Mediterranean conditions, allowing experimentation on setting river flow thresholds required for a good ecological status within the context of the European Water Framework Directive. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. NATURAL AND ARTIFICIAL RADIOACTIVITY IN BULGARIAN SOILS ALONG THE DANUBE RIVER

    Directory of Open Access Journals (Sweden)

    I YORDANOVA

    2005-07-01

    Full Text Available Data from gamma-spectrometry analyses of soils and sediments samples taken along the Danube river is presented in the paper. Results about the content of natural and artifi cial radionuclides like Sr-90 and Cs-137 are discussed. The region around the Kozloduj NPP including its exclusion zone is investigated in more details. Data from the last years is compared with such from former investigations of similar samples from the region. The soil is a natural depot and initial reservoir for spreading of all man-made radionuclides and natural radioactivity. The man-made isotopes with the longest half-life time, like Sr-90 and Cs-137 are mainly investigated. Because of their feature to be bioelements, that is to include themselves in human’s metabolism, they are especially dangerous when their concentrations in the nutritious chain increase. That is why the investigation of these nuclides together with the natural once like uranium, thorium and radium started in 1978 with annual determination of their concentrations in soils collected from the region of “Kozloduj” NPP and some places along the Danube river potentially exposed to radioactive contamination. The aim was to make a picture of the radioecological status of the soils along the Danube river. The period after 1986 is concerned as the accident in Chernobyl’s NPP changed basically the radioactive situation in the country.

  9. NATURAL RADIOACTIVITY IN SEDIMENTS AND RIVER BANK SOIL OF KALLADA RIVER OF KERALA, SOUTH INDIA AND ASSOCIATED RADIOLOGICAL RISK.

    Science.gov (United States)

    Venunathan, N; Kaliprasad, C S; Narayana, Y

    2016-10-01

    The paper presents the activity concentrations of 232Th, 226Ra and 40K in the sediments and river bank soil samples collected from the Kallada river environs of coastal Kerala. The radiological risks associated with these radionuclides were calculated. The samples were processed following standard procedure, and activity was counted using a high-efficiency 5″ × 5″ NaI (Tl) detector coupled to GSPEC gamma spectroscopy system. The mean values of measured activities of 232Th, 226Ra and 40K in soil samples were found to be 98.1 ± 0.4, 60.3 ± 1.1 and 343.4 ± 1.8 Bq kg-1, respectively, which results in an average absorbed dose rate of 103 nGy h-1 The corresponding values for sediment samples were found to be 88.0 ± 0.4, 48.6 ± 0.9 and 423.2 ± 2.0 Bq kg-1, respectively, with a resulting absorbed dose rate of 95 nGy h-1 Radium equivalent activity, annual effective dose equivalent, the external and internal hazard indices were determined and compared with recommended limits. The results of the work provide background data on natural radioactive isotopes, which are useful in the assessment of human radiation exposure from natural environment. The accumulation of information on natural radiation is of great value for radiation protection. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Population growth and natural-resources pressures in the Mekong River Basin.

    Science.gov (United States)

    Pech, Sokhem; Sunada, Kengo

    2008-05-01

    The Mekong River Basin possesses the region's largest potential water source and related resources, which support ongoing economic development and basin community livelihoods. It is currently witnessing a major demographic transition that is creating both opportunities and challenges. An analysis of the complex relationship between demographic changes and impacts on the natural-resource base confirms that resource exploitation is occurring not only to meet growing domestic needs but also for other vested interests. Population, together with other major drivers, such as institutions, markets, and technology, will have a very strong bearing on the way in which the rich resources of the Mekong River Basin are developed and distributed in the present and future. The Mekong River Basin's rich resources, and the benefits derived from them, are unevenly distributed both in time and geographically. Moreover, since the causes and impacts do not respect political boundaries, the Mekong countries need to jointly develop alternative management strategies to meet projected demands within the sustainable capacity of the Mekong River Basin natural-resource base.

  11. Optimization of the scheme for natural ecology planning of urban rivers based on ANP (analytic network process) model.

    Science.gov (United States)

    Zhang, Yichuan; Wang, Jiangping

    2015-07-01

    Rivers serve as a highly valued component in ecosystem and urban infrastructures. River planning should follow basic principles of maintaining or reconstructing the natural landscape and ecological functions of rivers. Optimization of planning scheme is a prerequisite for successful construction of urban rivers. Therefore, relevant studies on optimization of scheme for natural ecology planning of rivers is crucial. In the present study, four planning schemes for Zhaodingpal River in Xinxiang City, Henan Province were included as the objects for optimization. Fourteen factors that influenced the natural ecology planning of urban rivers were selected from five aspects so as to establish the ANP model. The data processing was done using Super Decisions software. The results showed that important degree of scheme 3 was highest. A scientific, reasonable and accurate evaluation of schemes could be made by ANP method on natural ecology planning of urban rivers. This method could be used to provide references for sustainable development and construction of urban rivers. ANP method is also suitable for optimization of schemes for urban green space planning and design.

  12. Restoring natural geomorphic process to river environments influenced by practical design constraints

    Science.gov (United States)

    Moir, H. J.

    2015-12-01

    The process restoration philosophy promotes the reinstatement of natural process (particularly the continuum of sediment transport processes) at the catchment scale. Associated with this approach is the concept that river biological communities, having evolved under natural/ un-impacted conditions, will respond positively to the reinstatement of natural physical function. The application of this 'let-the-river-do-the-work' approach is regarded as providing a sustainable alternative to traditional more 'hard engineering' approaches. However, often the reality is that full restoration of the controlling physical processes at the catchment scale is not feasible due to a variety of constraints (e.g. altered geomorphic regime, agriculture, infrastructure/ services, urban development, costs, etc.) and less ambitious objectives have to be set. Thus, under these typical constrained circumstances, can process restoration still be applied and, given the fundamental assumption of biophysical linkage, can ecology still be expected to respond positively? To elucidate these issues, we present four case studies from Scotland which represent the spectrum of process restoration application relating to almost no design constraints to very significant limitations (culvert daylighting within a housing development). We highlight that, despite significant constraints, physical river processes can (and should) always be considered in restoration design. The case studies demonstrate that natural physical processes (evidenced through indicators of sediment transport) quickly reinstate following construction; this was despite significant local constraints but reliant on physical/ geomorphic process being explicitly incorporated into to the design approach. Furthermore, evidence of associated improvements to the ecological/ habitat/ biotic condition of the restored sections of river were observed.

  13. Willow diversity in the fresh water tidal area of the river Schelde : natural, spontaneous, anthropogenic ?

    OpenAIRE

    Vanallemeersch, R; Zwaenepoel, A; Hoffmann, Maurice; Meire, Patrick

    1998-01-01

    The fresh water tidal area of the Schelde-estuary is characterised by a large willow diversity and a prominent presence of willow-dominated vegetation. Marsh vegetation consists for over 60 % of willow scrub and willow forest. These are natural vegetation types on fresh water tidal marshes, and are considered most important climax vegetation under fresh water tidal circumstances. Along the Schelde-estuary (as well as in other parts of the river valley) several willow species were planted thou...

  14. [Changes of wetland landscape pattern in Eastern Yellow River Delta Nature Reserve from 1995 to 1999].

    Science.gov (United States)

    Liu, Yan-fen; Zhang, Jie; Ma, Yi; Shan, Kai; Jin, Xiao-hua; Wang, Jin-he

    2010-11-01

    Based on the 1995-1999 Landsat TM images and geographic information systems, this paper analyzed the change characteristics of wetland landscape pattern in the Eastern Yellow River Delta Nature Reserve (an inlet of current flow path emptying into the sea), and related driving factors during the past few years pre and post the Yellow River diverting into Qing 8 anabranches in 1996. In 1995-1999, natural wetland was still the matrix of the wetlands in the Reserve, while constructed wetland only had a very small proportion. A substantial increase was observed in the area of non-wetlands, and a decline was found in the area of natural and constructed wetlands, among which, bare muddy tidal flats and marshes shrank significantly. Though the landscape types in the reserve had no homogeneity in the changes of shape and structure, and their aggregation degree in spatial distribution varied, the overall landscape structure became more complicated and fragmented, and the distribution of inner landscape types converted from continuously large blocks to discretely small patches. River diversion, flow break, and human activities were the main three driving factors leading to the changes of the wetland landscape pattern in the reserve.

  15. Effects of lateral confinement in natural and leveed reaches of a gravel-bed river: Snake River, Wyoming, USA

    Science.gov (United States)

    Leonard, Christina M.; Legleiter, Carl; Overstreet, Brandon T.

    2017-01-01

    This study examined the effects of natural and anthropogenic changes in confining margin width by applying remote sensing techniques – fusing LiDAR topography with image-derived bathymetry – over a large spatial extent: 58 km of the Snake River, Wyoming, USA. Fused digital elevation models from 2007 and 2012 were differenced to quantify changes in the volume of stored sediment, develop morphological sediment budgets, and infer spatial gradients in bed material transport. Our study spanned two similar reaches that were subject to different controls on confining margin width: natural terraces versus artificial levees. Channel planform in reaches with similar slope and confining margin width differed depending on whether the margins were natural or anthropogenic. The effects of tributaries also differed between the two reaches. Generally, the natural reach featured greater confining margin widths and was depositional, whereas artificial lateral constriction in the leveed reach produced a sediment budget that was closer to balanced. Although our remote sensing methods provided topographic data over a large area, net volumetric changes were not statistically significant due to the uncertainty associated with bed elevation estimates. We therefore focused on along-channel spatial differences in bed material transport rather than absolute volumes of sediment. To complement indirect estimates of sediment transport derived by morphological sediment budgeting, we collected field data on bed mobility through a tracer study. Surface and subsurface grain size measurements were combined with bed mobility observations to calculate armoring and dimensionless sediment transport ratios, which indicated that sediment supply exceeded transport capacity in the natural reach and vice versa in the leveed reach. We hypothesize that constriction by levees induced an initial phase of incision and bed armoring. Because levees prevented bank erosion, the channel excavated sediment by

  16. Research of Distribution of Elements in Natural Waters of the Selenga River Pool

    CERN Document Server

    Ganbold, G; Gerbish, S; Dalhsuren, B; Bayarmaa, Z; Maslov, O D; Sevastiyanov, D V

    2001-01-01

    The distribution of heavy metals in natural waters of the Selenga river pool was investigated. The contents of elements were determined using X-ray analysis with complete external reflection (XRACER). The zones with excess of the average contents of elements in comparison with reference samples were found out, that specifies their pollution by metals. It is offered in these zones to organize the regular water quality monitoring for supervision over the condition of the water ecosystems and to carry out actions on decrease of anthropogenous load and pollution of natural waters.

  17. Evaluating natural gas development impacts on stream ecosystems in an Upper Colorado River watershed

    Science.gov (United States)

    Holloway, J. M.; Bern, C.; Schmidt, T. S.; McDougal, R. R.; Clark, M. L.; Stricker, C. A.; Wolf, R. E.

    2011-12-01

    Oil and gas development in the western United States is increasingly placing at odds the management of two critical natural resources: fossil fuels and water. Muddy Creek, part of the Upper Colorado River watershed, is a semi-arid catchment in a sagebrush steppe ecosystem. Muddy Creek flows throughout the year and includes both perennial and ephemeral tributaries. Primary land use includes livestock grazing, oil and gas development, and recreational activities. A multi-discipline study has been initiated to determine potential impacts of the projected increase of coal bed natural gas development. Hundreds of permits for drilling co-produced waters have been issued, but low energy prices have slowed development. A watershed assessment was conducted in 2010 to determine areas within the watershed that are more susceptible to mobilization of trace elements that occur in soils forming on marine shales. Soil, stream sediment, and water samples were collected and analyzed for major elements and a suite of trace elements, with arsenic and selenium identified as potential elements of concern. A study of benthic and riparian invertebrates is being conducted to evaluate the uptake of these elements into the food web at targeted locations in the Muddy Creek watershed. Continued work will address sources of salinity to Muddy Creek, and ultimately to the Upper Colorado River. Impacts from energy development can include mobilization of naturally occurring sulfate salts through soil disturbance. Formation waters currently discharged to the surface from two failed wells within the watershed will be evaluated for their contribution to salinity, as well as dissolved organic carbon, nitrogen species, and trace elements, to the Upper Colorado River. Upon completion, this study will provide a baseline that can assist in land-use management decisions as oil and gas extraction expands in the Upper Colorado River watershed.

  18. Fishfauna from the lowland Mures River (Romania and the floodplain natural park area (Western Romania

    Directory of Open Access Journals (Sweden)

    Diana CUPSA

    2009-05-01

    Full Text Available The lowland Mures river has approximately 120 km in length, thereof more than 80 kilometers are comprised on the Mures Floodplain Natural Park that was established since the year 2007. This river stretch has different biotopes with lotic or lentic semblances with very characteristic and diverse fish fauna. Along the lowland main stream a system of canals, marshes and pools are connected. The results of repeated ichtiological surveys carried out during the years 1998 – 2001 and 2004 reveals that 48 fish species live in this river sector and other 2 species has uncertain presence. Most of the species from the river mainstream has maintain their former abundance (24 species while other 16 fish species has increased their abundance. The burbot Lota lota and Zingel zingel becomes frequent in the lowland Mures, probably as consequence of their population renewal. The number of fish species that having undergone regression is less (4 species and the exotic species present here are limited to 8 species. The major threatening factors in the lowland Mures represents the mineral aggregate extractions directly from the riverbed and the waste waters spill. Subsequent, the meanders and backwaters shortening or cutting down has a negative impact on the fish populations.

  19. Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix D: Natural River Drawdown Engineering

    National Research Council Canada - National Science Library

    2002-01-01

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

  20. FUNCTIONAL GROUP ANALYSIS OF SUWANNEE RIVER FULVIC ACID WITH REACTIVE FLUORESCENT PROBES (R822832)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  1. Metal concentrations in aquatic environments of Puebla River basin, Mexico: natural and industrial influences.

    Science.gov (United States)

    Morales-García, S S; Rodríguez-Espinosa, P F; Shruti, V C; Jonathan, M P; Martínez-Tavera, E

    2017-01-01

    The rapid urban expansion and presence of volcanoes in the premises of Puebla River basin in central Mexico exert significant influences over its aquatic environments. Twenty surface sediment samples from Puebla River basin consisting of R. Alseseca, R. Atoyac, and Valsequillo dam were collected during September 2009 and analyzed for major (Al, Fe, Mg, Ba, Ca, and K) and trace elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, V, and Zn) in order to identify the metal concentrations and their enrichment. R. Atoyac sediments presented higher concentrations of Ba (1193.8 μg g -1 ) and Pb (27.1 μg g -1 ) in comparison with the local reference sample values. All the metal concentrations except Sr for R. Alseseca sediments were within the range of local reference sample values indicating no significant external influence, whereas Valsequillo dam sediments had elevated concentrations of all the metals suggesting both natural and external influences in the study region. The magnitude of metal contamination was assessed using several indices such as geoaccumulation index (I geo ), enrichment factor (EF), degree of contamination (C d ), and pollution load index (PLI). The results suggest that As, Pb, and Zn were predominantly enriched in the Puebla River basin sediments. Comparing with sediment quality guidelines and ecotoxicological values, it is revealed that Cd, Cr, Cu, and Ni have possible harmful effects on the biological community. The present study provides an outlook of metal enrichment in Puebla River basin sediments, highlighting the necessity to conserve this river ecosystem for the near future.

  2. Natural flow regimes, nonnative fishes, and native fish persistence in arid-land river systems.

    Science.gov (United States)

    Propst, David L; Gido, Keith B; Stefferud, Jerome A

    2008-07-01

    Escalating demands for water have led to substantial modifications of river systems in arid regions, which coupled with the widespread invasion of nonnative organisms, have increased the vulnerability of native aquatic species to extirpation. Whereas a number of studies have evaluated the role of modified flow regimes and nonnative species on native aquatic assemblages, few have been conducted where the compounding effects of modified flow regimes and established nonnatives do not confound interpretations, particularly at spatial and temporal scales that are relevant to conservation of species at a range-wide level. By evaluating a 19-year data set across six sites in the relatively unaltered upper Gila River basin, New Mexico, USA, we tested how natural flow regimes and presence of nonnative species affected long-term stability of native fish assemblages. Overall, we found that native fish density was greatest during a wet period at the beginning of our study and declined during a dry period near the end of the study. Nonnative fishes, particularly predators, generally responded in opposite directions to these climatic cycles. Our data suggested that chronic presence of nonnative fishes, coupled with naturally low flows reduced abundance of individual species and compromised persistence of native fish assemblages. We also found that a natural flow regime alone was unlikely to ensure persistence of native fish assemblages. Rather, active management that maintains natural flow regimes while concurrently suppressing or excluding nonnative fishes from remaining native fish strongholds is critical to conservation of native fish assemblages in a system, such as the upper Gila River drainage, with comparatively little anthropogenic modification.

  3. Cytogenetics and biogeography: considerations about the natural origin of Hoplias malabaricus (Characiformes, Erythrinidae on the Iguaçu river

    Directory of Open Access Journals (Sweden)

    Vicari Marcelo Ricardo

    2006-01-01

    Full Text Available Hoplias malabaricus (trahyra is a widespread fish species over the Neotropical region with diversified inter-populational karyotypes (cytotypes, which may correspond to a species complex. Despite the wide distribution in the South American basins, some authors have questioned its natural origin in the Iguaçu river, an important Brazilian river basin which is characterized by several endemic fish species. We have analyzed the karyotype of H. malabaricus from different collection sites of this river, by conventional and banding methods. Our results, in addition to our previous data concerning geographic distribution of the cytotypes, contribute to better understand the origin of H. malabaricus on the Iguaçu river, reinforcing the proposition that it is a natural fish species in this river basin.

  4. Comparison of three different streamflow naturalization methods: an application for the Seine river basin

    Science.gov (United States)

    Terrier, Morgane; Perrin, Charles; De Lavenne, Alban; Andréassian, Vazken

    2017-04-01

    Observed streamflow time series are influenced by climate variations and human-induced perturbations. Nowadays, estimating the natural river flows appears essential in different fields, such as in water resources management, the legislation context or climate change studies. In the last two decades, several naturalization methods have been developed to estimate a naturalized streamflow series from an influenced one. However, they have been designed for specific applications and there is a lack of estimation of the associated uncertainties. Our study analyzes the respective strengths and weaknesses of three identified groups of methods. The first one, namely the neighborhood method, is based on a regionalization from geographically close catchments. The second one, namely the extension and reconstitution method, implement a hydrological model on the studied basin to estimate its naturalized streamflow time serie. Finally the third one is derived from a water balance analysis. These methods were compared on the case study of the Seine River Basin by considering the influence of the four large artificial reservoirs and focusing on a few flow gauging stations downstream. Since hydrological models are essential for the application of some naturalization methods, we used the GR5J model(implemented in the airGR R package*), and a modified version including a dam module. Results show that the different methods converge to similar impact assessments of reservoirs. However, significant differences appear between the natural low-flow estimates. Uncertainty estimates were also quantified and compared. *Coron L., C. Perrin, O. Delaigue, G. Thirel and V. Andréassian (in prep.) - airGR: A suite of lumped hydrological models in an R-package. Environmental Modelling and software.

  5. Analysis of dynamic wave model for flood routing in natural rivers

    Directory of Open Access Journals (Sweden)

    Reza BARATI

    2012-09-01

    Full Text Available Flooding is a common natural disaster that causes enormous economic, social, and human losses. Of various flood routing methods, the dynamic wave model is one of the best approaches for the prediction of the characteristics of floods during their propagations in natural rivers because all of the terms of the momentum equation are considered in the model. However, no significant research has been conducted on how the model sensitivity affects the accuracy of the downstream hydrograph. In this study, a comprehensive analysis of the input parameters of the dynamic wave model was performed through field applications in natural rivers and routing experiments in artificial channels using the graphical multi-parametric sensitivity analysis (GMPSA. The results indicate that the effects of input parameter errors on the output results are more significant in special situations, such as lower values of Manning’s roughness coefficient and/or a steeper bed slope on the characteristics of a design hydrograph, larger values of the skewness factor and/or time to peak on the channel characteristics, larger values of Manning’s roughness coefficient and/or the bed slope on the space step, and lower values of Manning’s roughness coefficient and/or a steeper bed slope on the time step and weighting factor.

  6. Carbon Transport, Transformation and Retention in Tropical Systems: The Lower Tana River Corridor as a Natural Laboratory

    Science.gov (United States)

    Govers, G.; Omengo, F.; Geeraert, N.; Bouillon, S.; Neyens, G.

    2016-12-01

    The lower Tana river in Kenya is an active river carrying high sediment and carbon loads, while lateral influxes from tributaries are very limited. We used this river as a natural laboratory to study the dynamics of carbon in the river-floodplain system. We measured carbon fluxes in the river as well as rates of carbon processing. Furthermore, we assessed carbon deposition in the floodplain and carbon mobilisation by river migration. We show that both within-river carbon dynamics as well as river-floodplain interaction can only be understood by accounting for autogenic river processes: the amounts of sediment (5-6 Mt yr-1) and particulate organic carbon (120-180 Mg yr-1) that are re-mobilised within the river reach (300 km) are similar to the amounts the reach receives from upstream. Carbon and sediment mobilisation are compensated for by deposition, both in the floodplain and within the river (point bars). This intensive exchange explains why the suspended sediment in the Tana river becomes finer (and more enriched in carbon) in the downstream direction, despite the deposition of fine, carbon-rich sediments in the floodplain. Contrary to what is found in temperate floodplains, overall carbon burial appears not to be very effective: most buried carbon is mineralised within decades after burial. However, burial efficiency is much higher for allochthonous organic carbon (deposited by the river) than for autochthonous organic carbon (sourced from local primary production). The Tana river does not only exchange carbon with its floodplain through deposition and remobilisation of POC. When floods occur, the floodplain acts as an important source of dissolved organic and inorganic carbon which is not only produced by organic carbon decomposition but also by weathering. Finally, there is significant CO2 outgassing from the Tana river, releasing 3-5 Mg C yr-1 to the atmosphere. Our study highlights the role of tropical river corridors as highly dynamic environments, which

  7. Identifying environmental controls on the shoreline of a natural river delta

    Science.gov (United States)

    Geleynse, N.; Hiatt, M.; Sangireddy, H.; Passalacqua, P.

    2015-05-01

    River deltas form where sediment-laden water debouches into a basin. The spatial delineation of a delta is nontrivial and yet is fundamental to systematically evaluating fluxes across its surface. Here we study shoreline dynamics of the Wax Lake Delta (WLD), a naturally developing delta, downstream of the Atchafalaya River, USA. We demonstrate the ability to extract hydrodynamic and morphodynamic shorelines from time series of satellite imagery and topography data, respectively. The hydrodynamic shoreline corresponds to the traditional dry-wet interface, whereas we introduce the concept of a morphodynamic shoreline demarcating the topset-foreset transition of a delta to quantitatively express the degree of inundation of a delta plain. These shorelines enable us to assess environmental controls on inundation of the WLD delta plain, noting the abundance of satellite imagery, whereas time series of bathymetric data from delta plains are scarce. From the analysis of NOAA and U.S. Geological Survey environmental data, we identify the effects of river discharge, tides, wind, and vegetation on shoreline position. In particular, using Delft3D simulations and a simplified momentum balance, we highlight the nonuniform and nonlinear effect of wind on delta plain inundation. Our analyses reveal that wind, riverine discharge, and tides significantly contribute to inundation of the WLD, and hence, incorporating their interaction is essential to the accurate modeling of hydrodynamics and ecodynamics of the WLD delta plain, as well as to the dynamic shape of delta plains in general.

  8. Real-time Monitoring Network to Characterize Anthropogenic and Natural Events Affecting the Hudson River, NY

    Science.gov (United States)

    Islam, M. S.; Bonner, J. S.; Fuller, C.; Kirkey, W.; Ojo, T.

    2011-12-01

    The Hudson River watershed spans 34,700 km2 predominantly in New York State, including agricultural, wilderness, and urban areas. The Hudson River supports many activities including shipping, supplies water for municipal, commercial, and agricultural uses, and is an important recreational resource. As the population increases within this watershed, so does the anthropogenic impact on this natural system. To address the impacts of anthropogenic and natural activities on this ecosystem, the River and Estuary Observatory Network (REON) is being developed through a joint venture between the Beacon Institute, Clarkson University, General Electric Inc. and IBM Inc. to monitor New York's Hudson and Mohawk Rivers in real-time. REON uses four sensor platform types with multiple nodes within the network to capture environmentally relevant episodic events. Sensor platform types include: 1) fixed robotic vertical profiler (FRVP); 2) mobile robotic undulating platform (MRUP); 3) fixed acoustic Doppler current profiler (FADCP) and 4) Autonomous Underwater Vehicle (AUV). The FRVP periodically generates a vertical profile with respect to water temperature, salinity, dissolved oxygen, particle concentration and size distribution, and fluorescence. The MRUP utilizes an undulating tow-body tethered behind a research vessel to measure the same set of water parameters as the FRVP, but does so 'synchronically' over a highly-resolved spatial regime. The fixed ADCP provides continuous water current profiles. The AUV maps four-dimensional (time, latitude, longitude, depth) variation of water quality, water currents and bathymetry along a pre-determined transect route. REON data can be used to identify episodic events, both anthropogenic and natural, that impact the Hudson River. For example, a strong heat signature associated with cooling water discharge from the Indian Point nuclear power plant was detected with the MRUP. The FRVP monitoring platform at Beacon, NY, located in the

  9. Determination of natural radioactivity levels in sediments: Caravelas river, BA, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, R.F.; Trindade Filho, O.L.; Delgado, J.U.; Peixoto, J.G. P., E-mail: rfcarmo@bolsista.ird.gov.br, E-mail: octavio@ird.gov.br, E-mail: delgado@ird.gov.br, E-mail: guilherm@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Evangelista, H., E-mail: evangelista.uerj@gmail.com [Lab. de Radioecologia e Mudancas Globais (LARAMG/UERJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    Due to intensive human activity in the region and disorderly occupation, the Caravelas River estuary has not yet evaluated the contribution of natural radioactivity. In order to determine the natural radioactivity levels in sediments, the activities of {sup 238}U, {sup 232}Th and {sup 40}K, were calculated using a gamma spectrometry system for measuring the concentration of radiation in samples. Results for {sup 238}U, {sup 232}Th and {sup 40}K ranged from (18.03 to 191.51), (28.57 to 118.25) and (134.06 to 186.80) Bq.kg{sup -1}, respectively, within of detection limits. The estimated uncertainty levels were less than 10% (k = 1). (author)

  10. Considerations Regarding Alpine Rivers And Their Ligneous Vegetation With Myricaria germanica In The Maramureş Mountains Nature Park (Romania)

    OpenAIRE

    Danci Oana

    2014-01-01

    The habitat 3230 Mountain rivers and their ligneous vegetation with Myricaria germanica was not listed in the standard form based on which the Natura 2000 site ROSCI0124 Maramureș Mountains was declared. The aim of this study is to offer some new information regarding the structure, distribution and ecology of the Natura 2000 habitat 3230 Mountain rivers and their ligneous vegetation with Myricaria germanica in Maramureș Mountains Nature Park. The ecological importance of habitat 3230 results...

  11. Small karstic Dobra River (Croatia) suggested as natural laboratory for impactite research

    Science.gov (United States)

    Frančišković-Bilinski, Stanislav; Bilinski, Halka; Sikder, Arif M.

    2016-04-01

    An unexpected anomaly of magnetic susceptibility (MS) was observed in stream sediments of the upper course of the karstic Dobra River (Croatia). Preliminary results pointed to a possible impactite, formed by a shock event caused by a meteorite impact or by volcanic processes [1]. In addition to geophysical experiments, petrological and geochemical studies are reported [2, 3]. The multidisciplinary work for identification and confirmation of impact structure is still in progress. Results will be presented and the difficulties due to weathering and transport processes will be discussed and compared with recent literature [4, 5]. In reported results numerous evidences exist, which are in support of impact origin, such as vesicular glass with quench texture, ballen textures in the lechatelierite, presence of Troilite, etc. We suggest that the Dobra River from its source to the abyss in Ogulin (Upper Dobra) is a possible natural laboratory for studying processes of mixing between impactite material and fluvial sediments within a small area, including spherules exposed to water and in the overbank sediments. Especially the introduction of isotope studies in this research and enlargement of multinational team of experts are suggested. Literature: [1] Franči\\vsković-Bilinski, S., Bilinski, H., Scholger, R., Tomašić, N., Maldini, K. (2014): Magnetic spherules in sediments of the sinking karstic Dobra River (Croatia). Journal of soils and sediments 14(3), 600-614. [2] Franči\\vsković-Bilinski, S., Sikder, A.M., Bilinski, H., Castano, C.E., Garman, G.C. (2015): Traces of meteorite impact in the sediments of karstic Dobra River (Croatia). 15th International multidisciplinary scientific geoconference SGEM 2015 Conference proceedings, Vol. 1, 507-514. [3] Sikder, A.M., Franči\\vsković-Bilinski, S., Bilinski, H., Castano, C.E., Clifford, D.M., Turner, J.B., Garman, G.C. (2015): Petrographic analysis of the magnetic spherules from the sediments of karastic Dobra River

  12. Natural Post-Tsunami Recovery of the Mataquito River Mouth, after the 2010 Chilean Tsunami

    Science.gov (United States)

    Villagran, M. F.; Cienfuegos, R.; Almar, R.; Catalan, P. A.; Camaño, A.

    2011-12-01

    The ensuing tsunami from the Mw=8.8 2010 Chilean earthquake was one of the most destructive events on Chilean history (Fritz et al. 2011). It caused not only major damage and loss of infrastructure on several locations, but also drastic morphological changes on coastal environments (Cienfuegos et al., 2010). The large scale and magnitude of the change could be considered effectively as system resets. This situation presented a unique opportunity to witness the natural recovery of some coastal landforms such as sand spits. The Mataquito River mouth, located just in front of the rupture area where most of the earthquake energy was released (Lay et al. 2010), is an example of a natural coastal system heavily affected by the 2010 tsunami: its 8 km-long sand spit almost completely disappeared under the combined action of tsunami waves and the relatively large land subsidence (Vargas et al. 2011). After the earthquake and tsunami, we have monitored the coastal evolution of the river mouth using different techniques such as site surveys, airborne and satellite images, to characterize qualitatively and identify the main processes driving the formation and recovery of the sand spit by waves and wind. This was complemented with forcing information like wind, waves and river discharge in order to better understand the system dynamics. Our observations evidenced a massive accretion and a surprisingly fast coastal recovery . In fact, most of the original configuration of the spit was reformed in less than 18 months. On the contrary, Duao beach, located 15 km north of Mataquito, experienced a dramatic erosion probably by land subsidence and consequent beach response to incoming wave climate. In this work we discuss on the role of waves, longshore currents, river hydrology and land subsidence in determining the rapid coastal evolution experienced in the Mataquito area. Moreover, this ongoing research will adress whether morphological changes are definitive or not. References

  13. Towards the Application of a River Management Approach Encompassing most Natural Process Drivers : Lessons Learned from Freedom Space for Rivers in Quebec (Canada)

    Science.gov (United States)

    Biron, P.; Buffin-Belanger, T. K.; Massé, S.

    2015-12-01

    The consensus around the need for a shift in river management approaches to include more natural processes is steadily growing amongst scientists, practitioners and governmental agencies. Not only is this a sound way to increase resilience of fluvial systems and adapt to climate change, but it will likely result in improved water quality and better aquatic habitat. This paper presents the freedom space for rivers approach which we have developed recently in Quebec (Canada) to combine natural processes related to mobility, flooding and riparian wetland connectivity into a single index. The approach was applied to 3 contrasted rivers (de la Roche, Yamaska Sud-Est and Matane) to produce two main levels of freedom space, operating at two time scales: "short" (in geomorphic terms, i.e. management approach, but also strong inertia and resistance to change, particularly in agricultural watersheds. Our observations reveal that for such a shift in paradigm to operate, hydrogeomorphogical concepts must be better understood by those in charge of managing rivers, which is currently not the case in Quebec. The role of integrating scientific knowledge in the implementation of a freedom space for rivers management scheme will be discussed based on case studies in 3 watersheds: rivière du Nord, Coaticook and Mitis/Neigette. The original approach was applied only to the main branches, however the second phase of the project is also aiming to determine whether the impact of leaving more space for natural rivers to operate would be more beneficial in headwater tributaries than in higher-order reaches.

  14. Transforming river basins: Post-livelihood transition agricultural landscapes and implications for natural resource governance.

    Science.gov (United States)

    Sreeja, K G; Madhusoodhanan, C G; Eldho, T I

    2015-08-15

    The agricultural and livelihood transitions post globalization are redefining resource relations and redrawing landscapes in the Global South and have major implications for nascent natural resource governance regimes such as Integrated River Basin Management (IRBM). A mosaic of divergent reciprocations in resource relations were noticed due to livelihood transitions in the rural areas where previous resource uses and relations had been primarily within agriculture. The reconstitution of rural spaces and the attendant changes in the resource equations are observed to be creating new sites of conformity, contestation and conflicts that often move beyond local spaces. This paper critically reviews studies across the Global South to explore the nature and extent of changes in resource relations and agricultural landscapes post livelihood diversification and the implication and challenges of these changes for natural resource governance. Though there is drastic reduction in agricultural livelihoods throughout the Global South, changes in agricultural area are found to be inconsistent and heterogeneous in the region. Agriculture continues in the countrysides but in widely differentiated capacities and redefined value systems. The transformed agrarian spaces are characterized by a mosaic of scenarios from persistence and sustainable subsistence to differentiation and exploitative commercial practices to abandonment and speculation. The reconfigured resource relations, emergent multiple and multi-scalar interest groups, institutional and policy changes and altered power differentials in these diversified landscapes are yet to be incorporated into natural resource governance frameworks such as IRBM. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Large-river delta-front estuaries as natural “recorders” of global environmental change

    Science.gov (United States)

    Bianchi, Thomas S.; Allison, Mead A.

    2009-01-01

    Large-river delta-front estuaries (LDE) are important interfaces between continents and the oceans for material fluxes that have a global impact on marine biogeochemistry. In this article, we propose that more emphasis should be placed on LDE in future global climate change research. We will use some of the most anthropogenically altered LDE systems in the world, the Mississippi/Atchafalaya River and the Chinese rivers that enter the Yellow Sea (e.g., Huanghe and Changjiang) as case-studies, to posit that these systems are both “drivers” and “recorders” of natural and anthropogenic environmental change. Specifically, the processes in the LDE can influence (“drive”) the flux of particulate and dissolved materials from the continents to the global ocean that can have profound impact on issues such as coastal eutrophication and the development of hypoxic zones. LDE also record in their rapidly accumulating subaerial and subaqueous deltaic sediment deposits environmental changes such as continental-scale trends in climate and land-use in watersheds, frequency and magnitude of cyclonic storms, and sea-level change. The processes that control the transport and transformation of carbon in the active LDE and in the deltaic sediment deposit are also essential to our understanding of carbon sequestration and exchange with the world ocean—an important objective in global change research. U.S. efforts in global change science including the vital role of deltaic systems are emphasized in the North American Carbon Plan (www.carboncyclescience.gov). PMID:19435849

  16. Influence of mineralogical and heavy metal composition on natural radionuclide concentrations in the river sediments.

    Science.gov (United States)

    Suresh, G; Ramasamy, V; Meenakshisundaram, V; Venkatachalapathy, R; Ponnusamy, V

    2011-10-01

    The natural radiation level has been determined for the sediment samples of the Ponnaiyar River with an aim of evaluating the radiation hazard. The mineralogical characterizations of the sediments have been carried out using the Fourier Transform Infrared (FTIR) spectroscopic technique. The relative distribution of major minerals is determined by calculating extinction coefficient. The concentration and spatial distribution of heavy metals (Pb, Cr, Cu, Zn and Ni) have been studied to understand the heavy metal contamination and its level of toxicity. To evaluate the potential toxicity, heavy metal concentrations are compared with different toxicological and geological reference values. The comparison results suggest that the present metals create an adverse effect on the aquatic ecosystems associated with this river. To assess the sediment contamination due to the studied heavy metals, the Pollution Load Index (PLI) is calculated. Multivariate Statistical analyses (Pearson Correlation, Cluster and Factor analysis) were carried out between the parameters obtained from radioactivity, mineralogical and geochemical analysis to know the existing relations. Obtained results showed that the effect of mineralogy on level of radioactivity should be significant. However, mineralogy effect on heavy metal composition in the sediments should be limited, indicating that other factors such as vicinity of the pollution sources are more important. Also, the influence of mineralogical characterization on level of radioactivity is significant, whereas the influence of the heavy metal composition on level of radioactivity should be limited. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Natural Risks at the Bottom Side of Ameca River, in the State Limits of Jalisco and Nayarit, Mexico

    Science.gov (United States)

    Pinedo, K. G.; Maciel, R.; Pena, L. E.; García García, E. X.; Ramos Chavez, C.

    2016-12-01

    At world-wide level, the population centers are exposed to natural risks and more those that are located to borders of the rivers, where hydrometeorological and geologic phenomenon are conjugated, and even increased by the action of the man. From 1911 to 2015, the disasters registered in the world due to flood by river overflowing were 2 701, with 2 545 affected 224 110, of which 60 229 747 lost their homes and 4 449 031 deads, causing therefore an economic loss of approximately $549 052 761 dollars. The case of study is the low part of the Ameca River, the one of the main rivers of the states of Jalisco and Nayarit in the west zone of Mexico. It is interesting, since it have its mouth near the tourist area (with considerable affluence at national level), with infrastructure (airport and bridges) and towns of both referred states; as well because at the pass of the years, this river have had overflows affecting municipalities, bridges and loss of mangrove swamp. In order to determine the feasible impacts to happen with the overflow of the Ameca River, the aerial photographs of area of study and satellite images were analyzed (historical and present), likewise information of the river basin physical environment generated by INEGI with special emphasis in the low part of the river basin and a campaign of work field, to delimit the zones that have shown some affectation. The objective of this investigation is to contribute to the risk analysis of the adjacent localities to the river, with the purpose of diminishing the impact in the population. As preliminary results appear maps with boundaries of paleo-channels, which mark the zone of influence during overflows of the Ameca River, the towns which can be affected and the population exposed.

  18. The Dnieper River Aquatic System Radioactive Contamination; Long-tern Natural Attenuation And Remediation History

    Science.gov (United States)

    Voitsekhovych, Oleg; Laptev, Genadiy; Kanivets, Vladimir; Konoplev, Alexey

    2013-04-01

    Near 27 year passed after the Chernobyl Accident, and the experience gained to study radionuclide behavior in the aquatic systems and to mitigate water contamination are still pose of interest for scientists, society and regulatory austerities. There are different aspects of radionuclide transport in the environment were studied since the Chernobyl fallout in 1986 covered the river catchments, wetlands, river, lakes/reservoirs and reached the Black Sea. The monitoring time series data set and also data on the radionuclides behavior studies in the water bodies (river, lakes and the Black Sea) are available now in Ukraine and other affected countries. Its causation analyses, considering the main geochemical, physical and chemical and hydrological process, governing by radionuclide mobility and transport on the way from the initially contaminated catchments, through the river-reservoir hydrological system to the Black Sea can help in better understanding of the main factors governing be the radionuclide behavior in the environment. Radionuclide washout and its hydrological transport are determined speciation of radionuclides as well as soil types and hydrological mode and also geochemistry and landscape conditions at the affected areas. Mobility and bioavailability of radionuclides are determined by ratio of radionuclide chemical forms in fallout and site-specific environmental characteristics determining rates of leaching, fixation/remobilization as well as sorption-desorption of mobile fraction (its solid-liquid distribution). In many cases the natural attenuation processes governing by the above mentioned processes supported by water flow transportation and sedimentation played the key role in self-rehabilitation of the aquatic ecosystems. The models developed during post-Chernobyl decade and process parameters studies can help in monitoring and remediation programs planed for Fukusima Daichi affected watersheds areas as well. Some most important monitoring data

  19. Analyzing the Natural Spatial Organization of Morphological Unit Landforms in the Lower Yuba River, CA

    Science.gov (United States)

    Wyrick, J. R.; Pasternack, G. B.; Bratovich, P.; Johnson, T.; Massa, D.

    2011-12-01

    A common practice in geomorphology involves delineating channel features at a specific scale and then characterizing their attributes, including hydraulics. Morphological units (MU) represent distinct local form-process associations at ~1-10 W scale that, once identified, are independent of the flow regime and can be used as the basic unit for stratifying other hydrodynamic and ecohydraulic characteristics of the river. However, most definitions of riverine landform patterns at the MU scale are subjective by nature, because no framework for objective delineation of landforms based purely on topography exists yet. They also do not account for lateral variability in MUs across the channel. This research addressed two questions: (1) can 2D (depth-averaged) hydrodynamic model results be used for identifying and classifying spatially distributed MUs at the sub-width spatial scale and (2) can such identified MUs have statistically significant spatial associations amongst themselves at the river and reach scales. A high-resolution digital elevation model of the ~25-mi Lower Yuba River, CA (LYR) was used along with hydrological observations to perform 3-ft resolution 2D modeling using SRH-2D. Depth and velocity outputs for different flows were then converted to rasters and used to characterize and classify MUs below the perennial minimum flow stage, between that and the bankfull stage, and above bankfull. At this scale of MU mapping, the in-channel units (riffle, glide, pool, run, chute, riffle transition, slackwater), bankfull bar units (lateral bar, medial bar, point bar, swale, hillside/bedrock), and off-channel units (floodplain, terrace, pond, tributary, cutbank) were identified across seven distinct reaches of the river segment. Statistical testing confirmed that the delineated MUs are spatially organized in a coherent, non-random pattern. Pools dominate in the confined reaches, while glides and riffles dominate in the wider, meandering reaches. Longitudinally, pools

  20. Fish invasions in the world's river systems: when natural processes are blurred by human activities.

    Directory of Open Access Journals (Sweden)

    Fabien Leprieur

    2008-02-01

    Full Text Available Because species invasions are a principal driver of the human-induced biodiversity crisis, the identification of the major determinants of global invasions is a prerequisite for adopting sound conservation policies. Three major hypotheses, which are not necessarily mutually exclusive, have been proposed to explain the establishment of non-native species: the "human activity" hypothesis, which argues that human activities facilitate the establishment of non-native species by disturbing natural landscapes and by increasing propagule pressure; the "biotic resistance" hypothesis, predicting that species-rich communities will readily impede the establishment of non-native species; and the "biotic acceptance" hypothesis, predicting that environmentally suitable habitats for native species are also suitable for non-native species. We tested these hypotheses and report here a global map of fish invasions (i.e., the number of non-native fish species established per river basin using an original worldwide dataset of freshwater fish occurrences, environmental variables, and human activity indicators for 1,055 river basins covering more than 80% of Earth's surface. First, we identified six major invasion hotspots where non-native species represent more than a quarter of the total number of species. According to the World Conservation Union, these areas are also characterised by the highest proportion of threatened fish species. Second, we show that the human activity indicators account for most of the global variation in non-native species richness, which is highly consistent with the "human activity" hypothesis. In contrast, our results do not provide support for either the "biotic acceptance" or the "biotic resistance" hypothesis. We show that the biogeography of fish invasions matches the geography of human impact at the global scale, which means that natural processes are blurred by human activities in driving fish invasions in the world's river systems

  1. Imbalance of Nature due to Contaminant Loads in the Culiacan River Watershed, Sinaloa, México

    Science.gov (United States)

    García Páez, F.; Ley-Aispuro, E.

    2013-05-01

    The Culiacan River discharges runoff from a large agricultural watershed into the wetlands at Ensenada de Pabellones ranked as a priority marine region of Mexico due to its high biodiversity and the economic importance of its fishing resources. This research estimated potential contaminant loads for BOD5, TSS, N and P from stormwater runoff and associated land use in the watershed. Previous studies had demonstrated the imbalance of nature due to land use change causing contamination by heavy metals, pesticides, sediment, phosphorus and eutrophication (Lopez and Osuna, 2002; Green and Paez, 2004, Gonzalez et al., 2006; Osuna et al., 2007). The methodology included: Characterizing the watershed according to land use, soil, vegetation, annual runoff and population density by sub-watershed; estimating the potential contaminant load and annual average concentrations of contaminants using the PLOAD program, comparing the result with monitored contaminant concentrations; and identifying the impact of pollutant loads in the watershed and coastal ecosystems and proposing management strategies to reduce or reverse the imbalance of nature caused by contamination in the Culiacan River watershed. Calculated contaminant loads in tonne/year were 13,682.4 of BOD5; 503,621.8 of TSS; 5,975.7 of N and 1,789.1 of P. The Tamazula and Humaya rivers watersheds provide 72% of the total load of BOD5, 68.5% of TSS, 77.6% of N and 62.7% of P discharged to the wetlands. Monitored results include: 89% of temperature observations were above 21°C, which is stressful to aquatic life due to a subsequent decrease in dissolved oxygen; 100% of the observations of P exceeded the ecological criteria for water quality; 71.5% of the observations for DO from 2001 to 2011, were above the ecological criteria for protection of aquatic life and 91.5% met the criteria for use in drinking water; 100% of the observations for BOD5 values remained in the range of Excellent to Good; 22% of the observations for the

  2. Deposition of Cryptosporidium parvum oocysts on natural organic matter surfaces: microscopic evidence for secondary minimum deposition in a radial stagnation point flow cell.

    Science.gov (United States)

    Liu, Yuanyuan; Janjaroen, Dao; Kuhlenschmidt, Mark S; Kuhlenschmidt, Theresa B; Nguyen, Thanh H

    2009-02-03

    A radial stagnation point flow (RSPF) system combined with a microscope was used to determine the deposition kinetics of Cryptosporidium parvum oocysts on quartz surfaces and silica surfaces coated with Suwannee River natural organic matter (SRNOM) in solutions with different ionic strengths. Microscopic evidence of C. parvum oocysts entrapped in the secondary minimum energy well was presented to show that among the entrapped C. parvum oocysts some were washed away by the radial flow and some were able to transfer to deep primary minima and become irreversibly deposited. Experimental data were compared with simulation results obtained by the convective-diffusion equation and Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The experimental results suggested that surface charge heterogeneity led to a higher attachment efficiency at low ionic strength. In addition, the maximum attachment efficiency was less than 1 at high ionic strength due to steric interaction.

  3. Cahaba River National Wildlife Refuge Natural Community and Rare Plant Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Cahaba River National Wildlife Refuge (CRNWR) administers approximately 3,414 acres alongthe Cahaba River in Bibb County, Alabama. The Refuge was established in 2002...

  4. Assessment of natural radioactivity in soil samples of Dez river sides – Khouzestan province

    Directory of Open Access Journals (Sweden)

    Nasri Nasrabadi

    2015-01-01

    Full Text Available Geographical features of each region of the world affect the activity concentration of natural radionuclides such as uranium, thorium and potassium. In this study, 26 soil samples were randomly collected from sides of the Dez River and transferred to the Laboratory for preparation. Activity concentration of natural radioactive materials was measured using p-type HPGe detector with a 38% relative efficiency. The results indicated that radioactivity concentration of 226Ra, 232Th and 40K in soil samples varied over a range of 15.97 - 32.87Bqkg-1, 8.04 - 33. 85 Bqkg-1 and 106.82 - 471.35 Bqkg-1, respectively while their mean values were 25.21, 19.71 and 289.57Bqkg-1 in that order. Statistical results at 5% internal error showed that the mean values of radionuclides' activity concentrations were lower than their defined ones--the average values of the world and Iran. The results of radiological parameters predicted no radioactivity danger in the region.

  5. Anthropogenic dissolved and colloid/nanoparticle-bound samarium, lanthanum and gadolinium in the Rhine River and the impending destruction of the natural rare earth element distribution in rivers

    Science.gov (United States)

    Kulaksız, Serkan; Bau, Michael

    2013-01-01

    The strong increase in the consumption of rare earth elements (REE) in high-tech products and processes is accompanied by increasing amounts of REE released into the environment. Following the first report of Gd contamination of the hydrosphere in 1996, anthropogenic Gd originating from contrast agents has now been reported worldwide from river and estuarine waters, coastal seawater, groundwater and tap water. Recently, microcontamination with La, that is derived from a point source where catalysts for petroleum refining are produced, has been detected in the Rhine River in Germany and the Netherlands. Here we report the occurrence of yet another REE microcontamination of river water: in addition to anthropogenic Gd and La, the Rhine River now also shows significant amounts of anthropogenic Sm. The anthropogenic Sm, which enters the Rhine River north of Worms, Germany, with the same industrial wastewater that carries the anthropogenic La, can be traced through the Middle and Lower Rhine to the Netherlands. At Leverkusen, Germany, some 250 km downstream from the point source at Worms, anthropogenic Sm still contributes up to 87% of the total dissolved Sm concentration of the Rhine River. Results from ultrafiltration suggest that while the anthropogenic Gd is not particle-reactive and hence exclusively present in the truly dissolved REE pool (Worms get close to and well-above, respectively, the levels at which ecotoxicological effects have been documented. Because of the increasing use of REE and other formerly "exotic" trace elements in high-tech applications, these critical metals have now become emerging contaminants that should be monitored, and it appears that studies of their biogeochemical behavior in natural freshwaters might soon no longer be possible.

  6. Using epiphytic lichens to monitor nitrogen deposition near natural gas drilling operations in the Wind River Range, WY, USA

    Science.gov (United States)

    Jill A. McMurray; Dave W. Roberts; Mark E. Fenn; Linda H. Geiser; Sarah Jovan

    2013-01-01

    Rapid expansion of natural gas drilling in Sublette County, WY (1999-present), has raised concerns about the potential ecological effects of enhanced atmospheric nitrogen (N) deposition to the Wind River Range (WRR) including the Class I BridgerWilderness. We sampled annual throughfall (TF) N deposition and lichen thalli N concentrations under forest canopies in four...

  7. Preplanting Treatments and Natural Invasion of Tree Species Onto Former Agricultural Fields at the Tensas River National Wildlife Refuge, Louisiana

    Science.gov (United States)

    John W. McCoy; Bobby D. Keeland; Brian Roy Lockhart; Thomas Dean

    2002-01-01

    As part of a study of oak planting techniques for bottomland hardwood afforestation we examined the natural invasion of woody species onto former agricultural fields at Tensas River National Wildlife Refuge. Three replications of 14 treatments were established as 0.4 hectare (1 acre) plots in a complete randomized block design. Combinations of these treatments were...

  8. The role of natural organic matter in nitrite formation by LP-UV/H2O2 treatment of nitrate-rich water.

    Science.gov (United States)

    Semitsoglou-Tsiapou, Sofia; Mous, Astrid; Templeton, Michael R; Graham, Nigel J D; Hernández Leal, Lucía; Kruithof, Joop C

    2016-12-01

    The role of natural organic matter (NOM) on nitrite formation from nitrate photolysis by low pressure ultraviolet lamp (LP-UV) photolysis and LP-UV/H2O2 treatment was investigated. Nitrate levels up to the WHO guideline maximum of 50 mg NO3-/L were used in tests. The presence of 4 mg/L Suwannee River natural organic matter (NOM) led to increased nitrite yields compared to NOM-free controls. This was caused partly by NOM scavenging of OH radicals, preserving the produced NO2- as well as the ONOO- that leads to NO2- formation, but also via the production of radical species (1O2, O2- and OH) by the photolysis of NOM. In addition, solvated electrons formed by NOM photolysis may reduce nitrate directly to nitrite. For comparison, Nordic Lake NOM, representative of aquatic NOM, as well as Pony Lake NOM, which had a greater nitrogen content (6.51% w/w) than the other two types of NOM, were investigated, yielding similar nitrite levels as Suwannee River NOM. The results suggest that neither the type nor the nitrogen content of the NOM have an effect on the nitrite yields obtained over the range of UV/H2O2 doses applied (UV fluences of 500-2100 mJ/cm2 and hydrogen peroxide doses of 10, 25, and 50 mg/L). The findings indicate that for UV fluences above 1500 mJ/cm2 the resulting nitrite concentration can exceed the 0.1 mg/L EU regulatory limit for nitrite, suggesting that nitrite formation by LP-UV advanced oxidation of nitrate-rich waters is important to consider. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Catchment structure that supports organic matter providing a natural control on rising river nutrient concentrations

    Science.gov (United States)

    Stutter, Marc; Ibiyemi, Adekunle; Wang, Chen

    2017-04-01

    The connectivity of sources of pollution in catchments has been well studied and brings concepts such as pollution hotspots and critical source areas. However, consideration of the placement of other structures combating rising pollution impacts has been less considered. One such area that is receiving developing focus is the layout of riparian management and buffer strips. However, there are wider aspects of connectivity and landscape structure that can bring benefits to delivery and in-stream processing of pollution. These include wetlands, forests and the distribution of soils of differing connectivity of organic matter varying in bioavailability. Organic matter is a great modulator of catchment processes from controlling the potential of land use (e.g. constraints of soil organic matter and wetness on agricultural use), to the amount and form of nutrients leached from soils, to controls of dissolved organic matter on in-stream biology that responds to nutrient concentrations. As the fundamental control of ecosystem energy available for many heterotrophic processes it mediates uptake, recycling and speciation of N, P at many stages of the catchment from soils to waters; as such DOM can be considered as a nature-based solution exerting a background level of control on inorganic nutrients. This poster explores the role of different structural aspects of catchments that provide beneficial organic matter inputs to rivers. At the fine scale the lability of riparian soil and leaf litter DOC are considered. At a riparian management scale the local changes in buffer strip soil C and DOC relative to field soils are considered. At the largest scale spatial data are explored for riparian structure, forests, wetlands and soils differing in delivery and forms of C across major Scottish rivers and used as co-variates to explain differences in in-stream processing of nutrients.

  10. Leaf Morphology Variation of Populus nigra L. in Natural Populations along the Rivers in Croatia and Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Davorin Kajba

    2015-06-01

    Full Text Available Background and Purpose: The aim was to determine the morphological differences between the hairy type of European black poplar (Populus nigra subsp. caudina and the typical type from the riparian forests populations as well as between the river systems. Hairy black poplar spreads in a mosaic pattern across the Submediterranean climatic type along the River Neretva and the typical European black poplar is growing on alluvial soils along large rivers in the territory of Croatia and Bosnia and Herzegovina. Material and Methods: Samples for leaf morphometric analysis were collected in 17 natural populations of European black poplar along six rivers in Croatia and Bosnia and Herzegovina. Results: Discriminant analyses have determined that in the differentiation of population groups largely contribute some characters such as the distance between the leaf widest part and the leaf base (DBW and the petiole length (PL. The differences between populations and analysed groups, as well as the differences between populations belonging to a particular river system, were confirmed for all studied characteristics. Conclusions: Significant differences have been determined between the typical and the hairy type of European black poplar in the studied morphological traits and these dissimilarities are in accordance with the climatic differences in respective habitats of continental riparian forests and the Submediterranean type of climate. Populations sampled in the lower course of the River Neretva, which correspond to the hairy type of the European black poplar, have smaller leaves and a greater angle between the first lower lateral vein and the midrib.

  11. Morphometric Analysis to Extrapolate Geoecological Potential of the Rivers in the “Iron Gates” Natural Park (Banat, Romania

    Directory of Open Access Journals (Sweden)

    Tetelea Cristian

    2014-12-01

    Full Text Available The present study is based on morphometric analysis of watersheds from the “Iron Gates” Natural Park. Morphometric parameters of a river basin are influenced by a series of biotic and abiotic factors. This aspect makes the morphometric analysis very useful in describing the river systems and offers an image of all the interactions and processes that define the geoecological potential of running waters ecosystems. The parameters used in morphometric analysis are a good alternative for understanding the underlying geoecological factors at watershed scale, and especially where the necessary data on soil, lithology, geomorphology, vegetation and other are scarce.

  12. The Problems and Prospects of Sustainable Recreational Nature Management in the Small Bend of the Don River on the Example of the Basin of the Bolshaya Golubaya River

    Directory of Open Access Journals (Sweden)

    Vishnyakov Nikolay Vladimirovich

    2015-09-01

    Full Text Available The article is devoted to the opportunities of tourist-recreational events organization in the basin of the Bolshaya Golubaya river located in the small bend of the Don river. This area is characterized by rich natural, cultural, historical and recreational potential. The article contains the data on the expeditions to the studied areas during the field seasons of 2013-2014. The author also cites the data of statistical research performed using the method of expert assessment with the assistance of specialists in sports tourism and recreation – directors and employees of touristic companies of the city of Volgograd, who are tour operators for domestic tourism, and professional tourists. Using these data the author made numerous maps of the recreational activities forms, which are possible to implement on this territory. The generalized map of the recreational use of nature in the basin of Bolshaya Golubaya river was created on the basis of these materials. There are also hydrological and road networks of the region on this map. The studied area is suitable for organizing and conducting different recreational events: sports and health tourism, horse riding, cycling tourism, agrotourism, ethnographic tourism. Managers of tourism enterprises, sports and tour groups can use the results of this research at the stage of creation, organization and conduction of recreational events on this territory.

  13. Spatial and temporal analysis of natural resources degradation in the Likodra River watershed

    Directory of Open Access Journals (Sweden)

    Polovina Siniša

    2016-01-01

    Full Text Available Soil is an important natural resource whose proper use requires a good knowledge of all endogenous and exogenous factors that cause different types of degradation. Erosion is one of the forms of soil degradation. Erosion processes are characterized by a distinctive complexity and the factors affecting them are dynamics and change in space and time. A complex system degradation requires a multidisciplinary approach to the use of modern methods and techniques. Today, a large number of models are available for the assessment of soil loss through erosion as well as the levels of risk from erosion, today. Most of these are based on the logics of GIS thanks to its ability to sublimate heterogeneous information. In this paper, the analysis of spatial and temporal degradation of natural resources is carried out in the Likodra River watershed. The Likodra River is located in the northwestern part of the Republic of Serbia, and is positioned in the municipality of Krupanj. The main stream in the immediate vicinity of the town of Krupanj formed from four small streams that have expressed torrential character (the Bogoštica with the Kržava and the Čađavica with the Brštica. In May 2014, the urban area and rural parts of the municipality Krupanj were affected by catastrophic flash floods that resulted in the loss of human lives and enormous material damage. Soil degradation in the study area was analyzed using the Erosion Potential Method (EPM. The method is characterized by a high degree of reliability for determining the intensity of erosion, calculation of sediment yield and transport. The advantage of this method compared to other methods its lower complexity in terms of quantity of input parameters, simplicity and the possibility of application in GIS. In addition, the method has the advantage of choice, because it was developed in this area. The method is based on the analytical processing of data on factors affecting erosion. As the erosion

  14. Reed wetland extraction in the Yellow River Delta Nature Reserve based on knowledge inference technology

    Science.gov (United States)

    Fu, Xiaomin; Wang, Hong; Li, Ling

    2009-06-01

    With the reduction of sediments into the sea, the area of reed wetland, which is the key habitat of red-crowned crane, has been shrinking in the Yellow River Delta Nature Reserve, China. With Landsat Thematic Mapper (TM) images and field observations, we mapped the reed wetland using the knowledge inference technology. Six wetland types were extracted using a supervised classification method. To resolve the confusions between reeds and other wetland types, a set of rules were established. Firstly, reed wetland was separated from mudflat wetland, rearing and shrimp pond and water body by using the normalized digital vegetation index (NDVI). Secondly, reed wetland was distinguished from paddy field by using image texture information. Thirdly, the reed wetland was separated from the Chinese tamarisk by using the principal transformation. All these rules were built by using ERDAS Imagine's knowledge engineer. Reed wetland classification was conducted by using the neighbor analysis technology. The accuracy assessment shows that the knowledge-based classification obtained an overall accuracy of 89.02% and kappa coefficient of 0.89, which was better than the traditional supervised classification.

  15. Risk Assessment of Drought in the Yangtze River Delta Based on Natural Disaster Risk Theory

    Directory of Open Access Journals (Sweden)

    Gaofeng Fan

    2017-01-01

    Full Text Available The risk of drought in the Yangtze River Delta Region (YRDR was assessed using the method of natural disaster risk assessment. Based on the index of disaster risk, the assessment results of risk elements such as drought hazard and vulnerability were calculated in the YRDR. The division of relative drought risk levels in the YRDR was produced at the scale of county (city, district and township. The results indicated that the areas of highest hazard of drought are located in the northern area of the YRDR. Areas with the greatest vulnerability of drought included Shanghai, Jiaxing, Wuxi, and Hangzhou. The highest risks of drought were mainly distributed in the north of the YRDR; the proportion of slightly high and extremely high risk areas in Shanghai, Nantong, Zhenjiang, Yangzhou, and Taizhou (Jiangsu province is over 95%. The lowest-risk areas included the southeast coastal area of the YRDR, especially in Hangzhou, and Taizhou (Zhejiang province, where the proportion of slightly high and extremely high risk areas is below 5%. Based on this drought risk assessment, it is critical to establish a drought assessment system including both guarding against and addressing drought.

  16. Revealing the relationship between microbial community structure in natural biofilms and the pollution level in urban rivers: a case study in the Qinhuai River basin, Yangtze River Delta.

    Science.gov (United States)

    Cai, Wei; Li, Yi; Wang, Peifang; Niu, Lihua; Zhang, Wenlong; Wang, Chao

    River pollution is one of the most challenging environmental issues, but the effect of river pollution levels on the biofilm communities has not been well-studied. Spatial and temporal distribution characteristics of environmental parameters and the biofilm communities were investigated in the Qinhuai River basin, Nanjing, China. Water samples were grouped into three clusters reflecting their varying pollution levels of relatively slight pollution, moderated pollution, and high pollution by hierarchical cluster analysis. In different clusters, the biofilm communities mainly differed in the proportion of Actinobacteria, Firmicutes, and Proteobacteria. As the dominant classes of Proteobacteria, Alpha-, Beta- and Gammaproteobacteria seemed to show an upward trend followed by a small fluctuation in the abundance with the escalation of water pollution level. Results of redundancy analysis demonstrated that temperature, total nitrogen to total phosphorus ratios (TN/TP) and concentrations of ammonia nitrogen (NH3-N) and TN were mainly responsible for the variation in bacterial community structure. The occurrences of Alpha-, Beta- and Gammaproteobacteria were closely associated with higher temperature, higher concentrations of NH3-N and TN and a lower TN/TP ratio. This study may provide a theoretical basis for the water pollution control and ecological restoration in urban rivers under different pollution levels.

  17. Transformation products formation of ciprofloxacin in UVA/LED and UVA/LED/TiO2 systems: Impact of natural organic matter characteristics.

    Science.gov (United States)

    Li, Si; Hu, Jiangyong

    2018-04-01

    The role of natural organic matter (NOM) in contaminants removal by photolysis and photocatalysis has aroused increasing interest. However, evaluation of the influence of NOM characteristics on the transformation products (TPs) formation and transformation pathways of contaminants has rarely been performed. This study investigated the decomposition kinetics, mineralization, TPs formation and transformation pathways of antibiotic ciprofloxacin (CIP) during photolysis and photocatalysis in the presence of three commercial NOM isolates (Sigma-Aldrich humic acid (SAHA), Suwannee River humic acid (SRHA) and Suwannee River NOM (SRNOM)) by using UVA light emitting diode (UVA/LED) as an alternative light source. NOM isolates insignificantly affected CIP photolysis but strongly inhibited CIP photocatalysis due to competitive radical quenching. The inhibitory effect followed the order of SAHA (49.6%) > SRHA (29.9%) > SRNOM (21.2%), consistent with their •OH quenching abilities, SUVA254 values and orders of aromaticity. Mineralization rates as revealed by F- release were negatively affected by NOM during CIP photocatalysis. TPs arising from hydroxylation and defluorination were generally suppressed by NOM isolates in UVA/LED and UVA/LED/TiO2 systems. In contrast, dealkylation and oxidation of piperazine ring were promoted by NOM. The enhancement in the apparent formation kinetics (kapp) of TP245, TP291, TP334a, TP334b and TP362 followed the order of SRNOM > SRHA > SAHA. kapp values were positively correlated with O/C ratio, carboxyl content, E2/E3 and fluorescence index (FI) of NOM and negatively related with SUVA254 values. The observed correlations indicate that NOM properties are important in determining the fate and transformation of organic contaminants during photolysis and photocatalysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Considerations Regarding Alpine Rivers And Their Ligneous Vegetation With Myricaria germanica In The Maramureş Mountains Nature Park (Romania

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    Danci Oana

    2014-10-01

    Full Text Available The habitat 3230 Mountain rivers and their ligneous vegetation with Myricaria germanica was not listed in the standard form based on which the Natura 2000 site ROSCI0124 Maramureș Mountains was declared. The aim of this study is to offer some new information regarding the structure, distribution and ecology of the Natura 2000 habitat 3230 Mountain rivers and their ligneous vegetation with Myricaria germanica in Maramureș Mountains Nature Park. The ecological importance of habitat 3230 results from the capacity of Myricaria germanica to colonize new deposits of gravels and set up new biocoenoses, this ability being possible only in the case of natural morphodynamics of the mountain streams, not influenced by human activities.

  19. Influence of natural and anthropogenic factors on the distribution of xerothermic plants in the lower San river valley (SE Poland

    Directory of Open Access Journals (Sweden)

    Rafał Krawczyk

    2012-12-01

    Full Text Available The aim of the present study was to describe the distribution of xerothermic species of vascular plants in the lower San River valley and the relationship between their density and the intensity of selected environmental (natural and anthropogenic factors. Xerothermic species occurred more frequently in the present valley floor compared to the glacial terrace. Within the present valley, the highest density was observed in the floodplain. The examined species also occurred more often on steep slopes of the valley, at the margins of the present valley terraces, and in the area of occurrence of aeolian sands. Moreover, a positive correlation has been found between the number of xerothermic species and the area of polyhemeroby ecosystems. The distribution of xero- and thermophilous species is determined by natural edaphic and geomorphological factors as well as anthropogenic ones (land use, lowering of the groundwater level as a result of river regulation.

  20. PROTECTED AREAS IN REGIONS OF INTENSIVE ECONOMICAL ACTIVITY: CONFLICT OF NATURE PROTECTION AND NATURE USE (CASE STUDY OF DOVINĖ RIVER CATCHMENT

    Directory of Open Access Journals (Sweden)

    RITA LINKEVICIEN

    2007-12-01

    Full Text Available Nature protection and economical activity clash of interests is analysed on the example of Dovin River catchment, situated in the south western part of Lithuania. It is a unique wetland complex consisting from Žuvintas Lake and the surrounding bogs (Fig. 1. Žuvintas Lake became the first protected area in Lithuania in 1937. However, the lake is situated in one of the most fertile region ofLithuania, where the methods of intensive farming activity is being employed for a long time. Eutrophication processes and overgrowth of this shallow lake has been very active during the several decadesand the lake has lost its ecological value. Therefore the main goal of this article is to analyse the anthropogenic influence towards the water bodies and protected natural values situated in the territoryof intensive economical activity. Cartographical material of different periods is being used for the evaluation of the hydrographical network transformations in Dovin River catchment. Hydrochemical parameters of the periods 1953–1954, 1960–1961, 1980–1982; 1993–2003; 2004–2005 of the water bodies in Dovin River catchment are being analysed. The field works in order to investigate the water quality in Dovin River and it‘s tributaries were made in spring of 2005. Water samples wereanalysed in laboratory of the Institute of Geology and Geography according water quality analysis methods approved by Lithuanian Ministry of Environment (Table 2. Water quality was evaluatedaccording maximum residue limits (MRL in surface waters (Table 3. The results of the study showed that although Žuvintas Lake is being protected for 70 years, the farming activity intensified constantly in its catchment. Canalised river beds and sluice–regulated hydrological regime of the lakes diminished the natural self–cleaning abilities of the water system. The average annual decrease of the lake specular surface was about 1,1 ha in the period of 1961–2003. The average annual

  1. Tracing the origin of suspended sediment in a large Mediterranean river by combining continuous river monitoring and measurement of artificial and natural radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Zebracki, Mathilde, E-mail: zebracki@free.fr [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Eyrolle-Boyer, Frédérique [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Evrard, Olivier [Laboratoire des Sciences du Climat et de l' Environnement (LSCE/IPSL), Unité Mixte de Recherche 8212 (CEA/CNRS/UVSQ), Gif-sur-Yvette (France); Claval, David [Laboratoire d' Etudes Radioécologiques en milieu Continental et Marin (LERCM), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Saint-Paul-lez-Durance (France); Mourier, Brice [Université Lyon 1, UMR 5023 Ecologie des Hydrosystèmes Naturels et Anthropisés, ENTPE, CNRS, 3, Rue Maurice Audin, F-69518 Vaulx-en-Velin (France); Université de Limoges, GRESE, EA 4330, 123 avenue Albert Thomas, 87060 Limoges (France); Gairoard, Stéphanie [Centre de Recherche et d' Enseignement de Géosciences de l' Environnement (CEREGE), Unité Mixte 34 (AMU/CNRS/IRD), Aix-en-Provence (France); and others

    2015-01-01

    Delivery of suspended sediment from large rivers to marine environments has important environmental impacts on coastal zones. In France, the Rhone River (catchment area of 98,000 km{sup 2}) is by far the main supplier of sediment to the Mediterranean Sea and its annual solid discharge is largely controlled by flood events. This study investigates the relevance of alternative and original fingerprinting techniques based on the relative abundances of a series of radionuclides measured routinely at the Rhone River outlet to quantify the relative contribution of sediment supplied by the main tributaries during floods. Floods were classified according to the relative contribution of the main subcatchments (i.e., Oceanic, Cevenol, extensive Mediterranean and generalised). Between 2000 and 2012, 221 samples of suspended sediment were collected at the outlet and were shown to be representative of all flood types that occurred during the last decade. Three geogenic radionuclides (i.e., {sup 238}U, {sup 232}Th and {sup 40}K) were used as fingerprints in a multivariate mixing model in order to estimate the relative contribution of the main subcatchment sources—characterised by different lithologies—in sediment samples collected at the outlet. Results showed that total sediment supply originating from Pre-Alpine, Upstream, and Cevenol sources amounted to 10, 7 and 2.10{sup 6} tons, respectively. These results highlight the role of Pre-Alpine tributaries as the main sediment supplier (53%) to the Rhone River during floods. Other fingerprinting approaches based on artificial radionuclide activity ratios (i.e., {sup 137}Cs/{sup 239+240}Pu and {sup 238}Pu/{sup 239+240}Pu) were tested and provided a way to quantify sediment remobilisation or the relative contributions of the southern tributaries. In the future, fingerprinting methods based on natural radionuclides should be further applied to catchments with heterogeneous lithologies. Methods based on artificial radionuclides

  2. Effects of cross-sectional geometry, vegetation and ice on flow resistance and conveyance of natural rivers

    OpenAIRE

    Helmiö, Terhi

    2004-01-01

    The accurate estimation of local hydraulics, i.e. local flow velocities and water depths, is necessary for the restoration and protection of biodiversity. The aim of the thesis was to develop methods and models for designing and evaluating the hydraulic aspects of restoration, rehabilitation and environmental flood management in running waters. Methods for the estimation of flow resistance in natural complex rivers and channels that have composite flow resistance and/or a compound channel...

  3. Natural vs Anthropocene Streams in Europe: History, Ecology and Implications for Sustainable River Restoration

    Science.gov (United States)

    Brown, T. G.; Lespez, L.; Sear, D. A.; Houben, P.; Klimek, K.

    2016-12-01

    In Europe as in North America the prevailing model of `natural' lowland streams is incised-meandering channels with silt-clay floodplains, and this model is the template for stream restoration. This papers tests this proposition using geological and historical data from across Europe and examines the implications for carbon sequestration and channel-floodplain restoration. Floodplain chronostratigraphy shows that early Holocene, pre-impact, European streams were predominantly multi-channel (anabranching) systems, and often choked with vegetation. In most cases floodplains were either non-existent or limited to adjacent organic-filled palaeochannels, spring/valley mires, flushes and hydromorphic soils. During the mid-Holocene and particularly 2-4 k BP, overbank silt-clay deposition transformed floodplains covering former wetlands and silting up secondary channels. This was followed by direct intervention in the Medieval period to a mill-based technological system. The final transformation was the `industrialiation of channels' through hard-engineering especially after the great acceleration of the Anthropocene. The primary factor in this sequence was accelerated soil erosion caused by deforestation and arable farming but with sediment delivery reflecting climatic fluctuations. Unlike North America where channel-floodplain transformation was rapid the transformation of European streams occurred over a much longer time-period in three phases; catchment driven sedimentation, Medieval management and finally industrialisation. Due to a combination of catchment controls, ecological change and the cultural value of this legacy it is both impractical, if not impossible, to restore European rivers to their pre-transformation state. However, attempts to restore them to intermediate historical (pre-industrial) states with some areas of anabranching, would have both ecological and carbon offset benefits. Sustainable restoration designed to maximise ecosystem services must be

  4. Importance of Natural and Anthropogenic Environmental Factors to Fish Communities of the Fox River in Illinois.

    Science.gov (United States)

    Schnier, Spencer; Cai, Ximing; Cao, Yong

    2016-02-01

    The dominant environmental determinants of aquatic communities have been a persistent topic for many years. Interactions between natural and anthropogenic characteristics within the aquatic environment influence fish communities in complex ways that make the effect of a single characteristic difficult to ascertain. Researchers are faced with the question of how to deal with a large number of variables and complex interrelationships. This study utilized multiple approaches to identify key environmental variables to fish communities of the Fox River Basin in Illinois: Pearson and Spearman correlations, an algorithm based on information theory called mutual information, and a measure of variable importance built into the machine learning algorithm Random Forest. The results are based on a dataset developed for this study, which uses a fish index of biological integrity (IBI) and its ten component metrics as response variables and a range of environmental variables describing geomorphology, stream flow statistics, climate, and both reach-scale and watershed-scale land use as independent variables. Agricultural land use and the magnitude and duration of low flow events were ranked by the algorithms as key factors for the study area. Reach-scale characteristics were dominant for native sunfish, and stream flow metrics were rated highly for native suckers. Regression tree analyses of environmental variables on fish IBI identified breakpoints in percent agricultural land in the watershed (~64%), duration of low flow pulses (~12 days), and 90-day minimum flow (~0.13 cms). The findings should be useful for building predictive models and design of more effective monitoring systems and restoration plans.

  5. Comparing large number of metaheuristics for artificial neural networks training to predict water temperature in a natural river

    Science.gov (United States)

    Piotrowski, Adam P.; Osuch, Marzena; Napiorkowski, Maciej J.; Rowinski, Pawel M.; Napiorkowski, Jaroslaw J.

    2014-03-01

    Nature-inspired metaheuristics found various applications in different fields of science, including the problem of artificial neural networks (ANN) training. However, very versatile opinions regarding the performance of metaheuristics applied to ANN training may be found in the literature. Both nature-inspired metaheuristics and ANNs are widely applied to various geophysical and environmental problems. Among them the water temperature forecasting in a natural river, especially in colder climate zones where the seasonality plays important role, is of great importance, as water temperature has strong impact on aquatic life and chemistry. As the impact of possible future climate change on water temperature is not trivial, models are needed to allow projection of streamwater temperature based on simple hydro-meteorological variables. In this paper the detailed comparison of the performance of nature-inspired optimization methods and Levenberg-Marquardt (LM) algorithm in ANNs training is performed, based on the case study of water temperature forecasting in a natural stream, namely Biala Tarnowska river in southern Poland. Over 50 variants of 22 various metaheuristics, including a large number of Differential Evolution, as well as some Particle Swarm Optimization, Evolution Strategies, multialgorithms and Direct Search methods are compared with LM algorithm on ANN training for the described case study. The impact of population size and some control parameters of particular metaheuristics on the ANN training performance are verified. It is found that despite widely claimed large improvement in nature-inspired methods during last years, the vast majority of them are still outperformed by LM algorithm on the selected problem. The only methods that, based on this case study, seem competitive to LM algorithm in terms of the final performance (but not speed) are Differential Evolution algorithms that benefit from the concept of Global and Local neighborhood-based mutation

  6. Hydrography - RIVERS_OUTSTANDING_NRC_IN: Outstanding Rivers in Indiana Listed by the Natural Resource Commission (Bernardin-Lochmueller and Associates, 1:100,000, Line Shapefile)

    Data.gov (United States)

    NSGIC State | GIS Inventory — RIVERS_OUTSTANDING_NRC_IN represents river and stream segments on the NRC’s Outstanding Rivers list for Indiana. The source data was last updated in October 1997....

  7. Proteocephalidean larvae (Cestoda in naturally infected cyclopid copepods of the upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Dina Lúcia Morais Falavigna

    2003-01-01

    Full Text Available The occurrence, prevalence and infection intensity of proteocephalidean larvae in naturally infected intermediate hosts of the Upper Paraná River floodplain are reported. A total of 5,206 zooplanktonic and benthic organisms were analyzed, namely cyclopid (2,621 and calanoid (1,479 copepods, cladocerans (704, rotifers (307, chironomid larvae (41 and ostracods (54. Eight cyclopid copepods - two copepodids, one male and five females - comprising 0.3% of the cyclopid copepods examined, were naturally infected. The male infected belonged to a species of Paracyclops, and the females to Paracyclops sp., Thermocyclops minutus and Mesocyclops longisetus.

  8. A Natural Heritage Inventory of the Rappahannock River Valley National Wildlife Refuge Potential Acquisition Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report documents the results of a project undertaken through this cooperative agreement to inventory the Rappahannock River Valley National Wildlife Refuge...

  9. Copper isotope fractionation during equilibration with natural and synthetic ligands.

    Science.gov (United States)

    Ryan, Brooke M; Kirby, Jason K; Degryse, Fien; Scheiderich, Kathleen; McLaughlin, Mike J

    2014-01-01

    As copper (Cu) stable isotopes emerge as a tool for tracing Cu biogeochemical cycling, an understanding of how Cu isotopes fractionate during complexation with soluble organic ligands in natural waters and soil solutions is required. A Donnan dialysis technique was employed to assess the isotopic fractionation of Cu during complexation with the soluble synthetic ligands ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), iminodiacetic acid (IDA) and desferrioxamine B (DFOB), as well as with Suwannee River fulvic acid (SRFA). The results indicated enrichment of the heavy isotope ((65)Cu) in the complexes, with Δ(65)Cu complex-free values ranging from +0.14 to +0.84‰. A strong linear correlation was found between the logarithms of the stability constants of the Cu complexes and the magnitudes of isotopic fractionation. These results show that complexation of Cu by organic ligands can affect the isotopic signature of the free Cu ion. This free Cu is considered the most bioavailable species, and hence, our results highlight the importance of understanding fractionation processes in the uptake medium when using Cu isotopes to study the uptake mechanisms of organisms. These data contribute a vital piece to the emerging picture of Cu isotope cycling in the natural environment, as organic complexation plays a key role in the Cu cycle.

  10. Post-Release Performance of Natural and Hatchery Subyearling Fall Chinook Salmon in the Snake and Clearwater Rivers.

    Energy Technology Data Exchange (ETDEWEB)

    Connor, William P.

    2008-04-01

    In 2006, we continued a multi-year study to compare smolt-to-adult return rate (SAR) ratios between two groups of Snake River Basin fall Chinook salmon Oncorhynchus tshawytscha that reached the sea through a combination of either (1) transportation and inriver migration or (2) bypass and inriver migration. We captured natural subyearlings rearing along the Snake and Clearwater rivers and implanted them with passive integrated transponder (PIT) tags, but knew in advance that sample sizes of natural fish would not be large enough for precise comparisons of SAR ratios. To increase sample sizes, we also cultured Lyons Ferry Hatchery subyearlings under a surrogate rearing strategy, implanted them with PIT tags, and released them into the Snake and Clearwater rivers to migrate seaward. The surrogate rearing strategy involved slowing growth at Dworshak National Fish Hatchery to match natural subyearlings in size at release as closely as possible, while insuring that all of the surrogate subyearlings were large enough for tagging (i.e., 60-mm fork length). Surrogate subyearlings were released from late May to early July 2006 to coincide with the historical period of peak beach seine catch of natural parr in the Snake and Clearwater rivers. We also PIT tagged a large representative sample of hatchery subyearlings reared under a production rearing strategy and released them into the Snake and Clearwater rivers in 2006 as part of new research on dam passage experiences (i.e., transported from a dam, dam passage via bypass, dam passage via turbine intakes or spillways). The production rearing strategy involved accelerating growth at Lyons Ferry Hatchery, sometimes followed by a few weeks of acclimation at sites along the Snake and Clearwater rivers before release from May to June. Releasing production subyearlings has been suggested as a possible alternative for making inferences on the natural population if surrogate fish were not available. Smoltto-adult return rates are not

  11. River

    Directory of Open Access Journals (Sweden)

    Morel Mathieu

    2016-01-01

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

  12. Emigration of Natural and Hatchery Chinook Salmon and Steelhead Smolts from the Imnaha River, Oregon, Progress Report 2000-2002.

    Energy Technology Data Exchange (ETDEWEB)

    Cleary, Peter; Kucera, Paul; Blenden, Michael

    2003-12-01

    This report summarizes the emigration studies of the Nez Perce Tribe in the Imnaha River subbasin during the 2001 and 2002 migration years. A migration year for the Imnaha River is defined here as beginning July 31 of the previous year and ending July 30 the following year. The conclusion of the studies at the end of migration year 2002 marked the 11th year of the Nez Perce Tribe's Lower Snake River Emigration Studies. The Nez Perce Tribe has participated in the Fish Passage Center's Smolt Monitoring Program for nine of the 11 years. These studies collect and tag juvenile chinook salmon and steelhead at two locations in the fall, rkm 74 and rkm 7, and at rkm 7 during the spring. Data from captured and tagged fish provide an evaluation of hatchery production and releases strategies, post release survival of hatchery chinook salmon, abundance of natural chinook salmon, and downstream survival and arrival timing of natural and hatchery chinook salmon and steelhead. The hydrologic conditions that migrating fish encountered in 2001 were characterized as a drought and conditions in 2002 were characterized as below average. Hatchery chinook salmon had a mean fork length that was 34 mm greater in 2001 and 35 mm greater in 2002 than the mean fork length of natural chinook smolts. Hatchery steelhead smolt mean fork lengths were 39 mm greater than natural steelhead smolts in 2001 and 44 mm greater than natural steelhead smolt fork lengths in 2002. A significant difference (p < 0.05) between hatchery and natural chinook salmon and steelhead fork lengths has been documented by these emigration studies from 1997 to 2002. Hatchery chinook salmon were volitionally released in 2001 and 2002 and the 90% arrivals for 2001 and 2002 at the lower rkm 7 trap were within the range of past observations of 22 to 38 days observed in 1999 and 2000. We estimated that 93.9% of the 123,014 hatchery chinook salmon released in 2001 survived to the lower trap and 90.2% of the 303

  13. Sulfur Isotope Analysis of Minerals and Fluids in a Natural CO2 Reservoir, Green River, Utah

    Science.gov (United States)

    Chen, F.; Kampman, N.; Bickle, M. J.; Busch, A.; Turchyn, A. V.

    2013-12-01

    Predicting the security of geological CO2 storage sites requires an understanding of the geochemical behavior of the stored CO2, especially of fluid-rock reactions in reservoirs, caprocks and fault zones. Factors that may influence geochemical behavior include co-injection of sulfur gases along with the CO2, either in acid-gas disposal or as contaminants in CO2 storage sites, and microbial activity, such as bacterial sulfate reduction. The latter may play an important role in buffering the redox chemistry of subsurface fluids, which could affect toxic trace metal mobilization and transport in acidic CO2-rich fluids. These processes involving sulfur are poorly understood. Natural CO2-reservoirs provide natural laboratories, where the flow and reactions of the CO2-charged fluids and the activity of microbial communities are integrated over sufficient time-scales to aid prediction of long-term CO2 storage. This study reports on sulfur isotope analyses of sulfate and sulfide minerals in rock core and in CO2-charged fluids collected from a stacked sequence of natural CO2 reservoirs at Green River, Utah. Scientific drilling adjacent to a CO2-degassing normal fault to a depth of 325m retrieved core and fluid samples from two CO2 reservoirs in the Entrada and Navajo Sandstones and from the intervening Carmel Formation caprock. Fluid samples were collected from CO2-charged springs that discharge through the faults. Sulfur exists as sulfate in the fluids, as sedimentary gypsum beds in the Carmel Formation, as remobilized gypsum veins within a fault damage zone in the Carmel Fm. and in the Entrada Sandstone, and as disseminated pyrite and pyrite-mineralized open fractures throughout the cored interval. We use the stable sulfur (δ34S) and oxygen (δ18OSO4) isotopes of the sulfate, gypsum, and pyrite to understand the source of sulfur in the reservoir as well as the timing of gypsum vein and pyrite formation. The hydration water of the gypsum is also reported to explore the

  14. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every MRB_E2RF1catchment of selected Major River Basins...

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

    Science.gov (United States)

    Ulker, Riza

    2012-01-01

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

  16. Impact of Natural and Man-Made Factors on Mineral Composition of the Ardon River Water and Hydrophytes

    Science.gov (United States)

    Vadim, Ermakov; Elena, Korobova; Alexander, Degtyarev; Nina, Petrunina; Sergey, Tyutikov

    2013-04-01

    The Unal basin located in mountain region of Northern Ossetia (the Caucasus) belongs to Pb-Zn natural province with anthropogenic and natural transformation of the environment leading to risks of ecological damage. Activity of the Misursk Mining Combine and its Arkhon-Khosta tailings caused a significant local increase of Pb, Cd, Cu, Zn content in soils, water and biotic components relative to background values [1-5]. A catastrophic mud flow of 2002 and the later construction of a gas pipeline and a dam for hydroelectric power station changed local landscapes and biota (plants, algae, and amphibia). Biogeochemical studies performed in the area in 2001, 2003 and 2008 showed that in some cases the specified factors might change the structure of landscapes due to enhanced mass migration and the erosion of outcropping rocks which could be followed by corresponding transformation of the chemical composition of draining waters and flood plain soils, and could also change the character of species' invasion. Algae were proved to adapt and to indicate both natural and man-made transformation of the environment [3, 4]. A distinct relation between the particle size of the suspended matter in the Ardon river waters and water mineralization was discovered. However, heavy metals' concentration level in waters of the Ardon river appeared in general to be within the acceptable hygienic standards and therefore ecologically not critical. References 1. Degtyarev V.P., Ermakov V.V. Ecological and geochemical evaluation of the the Ardon river basin (Northern Ossetia). Geokhimiya, 1998, 1, 88-94. 2. Karpova E.A., Krechetova E.V., Degtyarev V.P. Parameters of heavy metal migration in soils of biogeochemical anomalies of the Northern Ossetia. Modern problems of soil contamination, Moscow State University, V. 1, 2007, 106-110. 3. Petrunina N.S., Ermakov V.V., Tuytikov S.F., Karpova E.A., Levkina L.M., Gololobova M.A. Biogeochemical identification of natural and technogenic polymetallic

  17. The harmony between the natural and anthropogenic environments within the natural parks. Case study- The Viseu river basin

    Directory of Open Access Journals (Sweden)

    Andrei SIMA

    2011-07-01

    Full Text Available By definition a natural park is a protected area designed to protect and conserve the natural environment in which the interaction between human activities and nature createda unique area, of significant environmental and cultural value and with great biodiversity.The main purpose of these natural parks is to maintain the harmony between humans and nature by protecting the biological diversity of the habitats and the environment. In recent years both the natural and anthropic areas of the Vişeu Basin have been greatly damaged by extreme hydric phenomenon caused by the chaotic deforestation of the area, increased precipitation, high pluvio-nival regime and the accentuated asymmetry of the basin itself. By developing certain hydrographical installations and conserving the protected areas a balance can be reached between the natural harmony and the strict necessities of the anthropic habitats. The first priority of this developing is theenvironmental legislation and biodiversity protection.

  18. Fire helps restore natural disturbance regime to benefit rare and endangered marsh birds endemic to the Colorado River

    Science.gov (United States)

    Conway, C.J.; Nadeau, C.P.; Piest, L.

    2010-01-01

    Large flood events were part of the historical disturbance regime within the lower basin of most large river systems around the world. Large flood events are now rare in the lower basins of most large river systems due to flood control structures. Endemic organisms that are adapted to this historical disturbance regime have become less abundant due to these dramatic changes in the hydrology and the resultant changes in vegetation structure. The Yuma Clapper Rail is a federally endangered bird that breeds in emergent marshes within the lower Colorado River basin in the southwestern United States and northwestern Mexico. We evaluated whether prescribed fire could be used as a surrogate disturbance event to help restore historical conditions for the benefit of Yuma Clapper Rails and four sympatric marsh-dependent birds. We conducted call-broadcast surveys for marsh birds within burned and unburned (control) plots both pre-and post-burn. Fire increased the numbers of Yuma Clapper Rails and Virginia Rails, and did not affect the numbers of Black Rails, Soras, and Least Bitterns. We found no evidence that detection probability of any of the five species differed between burn and control plots. Our results suggest that prescribed fire can be used to set back succession of emergent marshlands and help mimic the natural disturbance regime in the lower Colorado River basin. Hence, prescribed fire can be used to help increase Yuma Clapper Rail populations without adversely affecting sympatric species. Implementing a coordinated long-term fire management plan within marshes of the lower Colorado River may allow regulatory agencies to remove the Yuma Clapper Rail from the endangered species list. ?? 2010 by the Ecological Society of America.

  19. Epilithic algae distribution along a chemical gradient in a naturally acidic river, Río Agrio (Patagonia, Argentina).

    Science.gov (United States)

    Baffico, Gustavo D

    2010-04-01

    The epilithic algae distribution along a pH gradient and the relationship between the chemical gradient and biomass development were studied in Río Agrio, a naturally acidic river located in Patagonia (Argentina). The epilithic community was monitored during the summer of three consecutive years in sites located above and below the entrance of tributaries. The epilithic community showed differences between sites based on the chemical composition of the water and the precipitates that appear on the streambed of the river. The lowest biomass, diversity, and number of species were found at the most extreme part of the river in terms of pH (ca. 2) and element concentrations. Euglena mutabilis was the dominant species in this section of the river. As pH increased (ca. 3), the community changed to be dominated by filamentous green algae (Ulothrix spp., Mougeotia sp., Klebsormidium sp.) showing luxuriant growths in terms of biomass. With the inflow of a neutral tributary, the pH of Río Agrio increased above 3, and the precipitates of orange-red iron hydroxides appeared. The algal community was not affected by these precipitates or the low P concentrations, along the next 30 km of river downstream from this site. The apparent physical stress that the precipitates impose on algae is in fact a dynamic reservoir of P because diel cycle of Fe could be promoting precipitation and redissolution processes that binds and releases P from these precipitates. Where the pH increased above 6, precipitates of aluminum hydroxides appeared. At this site, the epilithic biomass and density decreased, some algae species changed, but the diversity and the number of species in general remained consistent with the upstream values. The physical stress of the Al precipitates on the algae is added to the chemical stress that represents the sequestering of P in these precipitates that are not redissolved, resulting P a limiting nutrient for algae growth.

  20. Assessment of heavy metal contamination in the sediments from the Yellow River Wetland National Nature Reserve (the Sanmenxia section), China.

    Science.gov (United States)

    Cheng, Qingli; Wang, Ruiling; Huang, Wenhai; Wang, Wenlin; Li, Xudong

    2015-06-01

    The Yellow River Wetland National Nature Reserve (the Sanmenxia section) is an important area of the Yellow River for two important hydrologic gauging stations: the Sanmenxia reservoir and the Xiaolangdi reservoir. Seven sites along the section were selected: Jiziling, Dinghuwan, Houdi, Canglonghu, Shangcun, Wangguan, and Nancun. After the microwave digestion with aqua regia, concentrations of Cu, Pb, Cd, Cr, Zn, and Mn in the sediments were analyzed by flame atomic absorption spectrometry with air-acetylene flame. The results showed that all the concentrations of Cr detected were from the lithogenic source, and 63 % Mn, 48 % Pb, 41 % Cu, 20 % Cd, and 12 % Zn were from the anthropogenic source. The values of the index of geo-accumulation pointed out that there was moderate contamination of Mn at the Dinghuwan (1.04) and Houdi (1.00) sites (class 2), while the modified degree of contamination denoted that the contamination at the Houdi site (2.02) was moderate, nil to very low at the Nancun and Shangcun sites and low at the other sites, consisting with the tendency of pollution load index. For metal toxicity, the sediment pollution index indicated that the sediments of the Canglonghu site were low polluted, that of the Houdi site is nearly slightly contaminated, and those of others were natural and uncontaminated. It was vital to evaluate the degree of contamination with individual and overall elements and even with the metal toxicity. Cu, Pb, and Mn contaminations were aggravated in the Sanmenxia section, and there maybe was one of the main anthropogenic sources of these metals along the Yellow River. The findings were expected to update the current status of the heavy metal pollution in the Sanmenxia section as well as to create awareness concerning the sound condition of the whole reaches of the Yellow River.

  1. Natural and anthropogenic hydrocarbons in sediments from the Chubut River (Patagonia, Argentina).

    Science.gov (United States)

    Commendatore, M G; Esteves, J L

    2004-05-01

    In March of 2001 a study was carried out to evaluate hydrocarbon levels in the lower course of the Chubut River. The study included 12 sample stations along the river from San Cristóbal Bridge to the confluence with the sea, in a 25 km straight-line extension in a urbanized area. In the first 11 stations, resolved aliphatic (RAli) hydrocarbons presented low values, between 0.07 and 0.96 microg/g dry weight (dw); the unresolved complex mixture (UCM) between 0.42 and 2.72 microg/g dw, and the total aliphatic (TAli) hydrocarbons between 0.55 and 3.07 microg/g dw. In the last station, at the mouth of Chubut river, these values increased to 460, 284, and 741 microg/g dw for RAli, UCM and TAli, respectively. The n-alkanes distribution indices and the compositional parameters suggested a predominantly biogenic origin in eleven stations, and a predominantly anthropogenic origin in the last station, with the highest hydrocarbon values. It is possible to conclude that the stations with low hydrocarbon values and biogenic origin predominance would constitute the baseline of aliphatic hydrocarbons for river sediments at this zone. The station with the highest hydrocarbon concentration and predominantly anthropic origin was related to the presence of Rawson city's port, where its activities (harbor and fishing vessels) generate hydrocarbon wastes unrelated to the river base profile in the study zone. Offshore, but within the river influence, there is an important fishing area of Argentine Red and Patagonian shrimps (Pleoticus muelleri and Artemesia longinaris, respectively).

  2. On-site treatment of turbid river water using chitosan, a natural organic polymer coagulant.

    Science.gov (United States)

    Sekine, M; Takeshita, A; Oda, N; Ukita, M; Imai, T; Higuchi, T

    2006-01-01

    Chitosan, acetylate of chitin, is a biodegradable cationic polymer. The objective of this study is to assess the applicability of chitosan as an on-site treatment agent of turbid water caused by river construction works and other diffused pollutions. The results of jar-tests indicate that floc of chitosan is much larger than that of aluminium sulfate, and turbidity treated by chitosan under moving water conditions is much lower than that of aluminium sulfate. Chitosan is applied to Imou River in Yamaguchi prefecture, where river construction work is going on. St.1 is located just below the construction work, St.2 is located about 250 m downstream from St.1, and St.3 is located about 350 m downstream from St.2. Initial turbidity of each station is 1,100, 937 and 313 NTU, respectively. By applying chitosan at St.1, turbidity of each station is drastically reduced to 1,100, 12 and 0 NTU. Chitosan could be helpful to reduce problems caused by turbidity in rivers.

  3. The Narew River Basin: A model for the sustainable management of agriculture, nature and water supply

    NARCIS (Netherlands)

    Gielczewski, Marek

    2003-01-01

    This thesis is a search for a method of environmental management that may lead to sustainable development in North-eastern Poland and the Warsaw region. The methods studied in this thesis provide the components of a decision support system for managing the water quality of the Narew River

  4. Natural cavity characteristics and cavity bird abundance on West Virginia forested islands of the Ohio River

    Science.gov (United States)

    James T. Anderson; Karen A. Riesz

    2013-01-01

    Wildlife habitats connected with forested islands and their back channels (areas where commercial traffic is prohibited) on the Ohio River are valuable to diverse species. However, quantitative data on the importance of these areas to cavity-nesting birds are lacking. We compared cavity-nesting bird use and habitat between back and navigational channel sides of islands...

  5. Morphological identification of Populus nigra × P. laurifolia natural hybrids in the flood-plain of Tom’ river

    Directory of Open Access Journals (Sweden)

    A. V. Klimov

    2016-10-01

    Full Text Available A comparative analysis of variability of morphological characteristics of Populus nigra L., Populus laurifolia Ledeb. (Salicaceae and their natural hybrids in the flood-plain of Tom’ river (Kemerovo Oblast revealed traits for identification of the natural hybrids. The most important of them are: the ribbing of the long shoots, types of short shoots of crown, location generative buds on the shoots, the number of bud’s glumes of the generative buds, and the shape of the leaf blade. The morphometric characteristics of leaves should be used to clarify the nature of the hybrid individuals. In female hybrids, the reliable diagnostic feature is the number of box cusps. Qualitative and quantitative characteristics of hybrids for the most part are of intermediate character, but the differentiation of shoots crown and location generative buds hybrids closer to the Populus laurifolia. Values morphometric attributes of leaves at hybrids in most cases authentically differ from ones P. nigra and P. laurifolia, and combinations of these differences in each hybrid model are individual. Hybrids don’t form separate populations, grow by single trees or form small clones in a flood-plain of Tom’ river. Occurrence of hybrids depends on stage of their development and increases in areas with significant anthropogenic pressure.

  6. QSAR models for the removal of organic micropollutants in four different river water matrices

    KAUST Repository

    Sudhakaran, Sairam

    2012-04-01

    Ozonation is an advanced water treatment process used to remove organic micropollutants (OMPs) such as pharmaceuticals and personal care products (PPCPs). In this study, Quantitative Structure Activity Relationship (QSAR) models, for ozonation and advanced oxidation process (AOP), were developed with percent-removal of OMPs by ozonation as the criterion variable. The models focused on PPCPs and pesticides elimination in bench-scale studies done within natural water matrices: Colorado River, Passaic River, Ohio River and Suwannee synthetic water. The OMPs removal for the different water matrices varied depending on the water quality conditions such as pH, DOC, alkalinity. The molecular descriptors used to define the OMPs physico-chemical properties range from one-dimensional (atom counts) to three-dimensional (quantum-chemical). Based on a statistical modeling approach using more than 40 molecular descriptors as predictors, descriptors influencing ozonation/AOP were chosen for inclusion in the QSAR models. The modeling approach was based on multiple linear regression (MLR). Also, a global model based on neural networks was created, compiling OMPs from all the four river water matrices. The chemically relevant molecular descriptors involved in the QSAR models were: energy difference between lowest unoccupied and highest occupied molecular orbital (E LUMO-E HOMO), electron-affinity (EA), number of halogen atoms (#X), number of ring atoms (#ring atoms), weakly polar component of the solvent accessible surface area (WPSA) and oxygen to carbon ratio (O/C). All the QSAR models resulted in a goodness-of-fit, R 2, greater than 0.8. Internal and external validations were performed on the models. © 2011 Elsevier Ltd.

  7. Comprehensive isolation of natural organic matter from water for spectral characterizations and reactivity testing

    Science.gov (United States)

    Leenheer, J.A.; Croue, J.-P.; Benjamin, M.; Korshin, G.V.; Hwang, C.J.; Bruchet, A.; Aiken, G.R.

    2000-01-01

    A variety of approaches were tested to comprehensively isolate natural organic matter (NOM) from water. For waters with high NOM concentrations such as the Suwannee River, Georgia, approaches that used combinations of membrane concentrations, evaporative concentrations, and adsorption on nonionic XAD resins, ion exchange resins and iron oxide coated sand isolated over 90% of the NOM. However, for waters with low NOM concentrations, losses of half of the NOM were common and desalting of NOM isolates was a problem. A new comprehensive approach was devised and tested on the Seine River, France in which 100 L of filtered water was sodium softened by ion exchange and vacuum evaporated to 100 mL. Colloids (32% of the NOM) were isolated using a 3,500 Dalton membrane by dialysis against 0.1 M HCl and 0.2 M HF to remove salts and silica. On the membrane permeate, hydrophobic NOM (42%) was isolated using XAD-8 resin and hydrophilic NOM (26%) was isolated using a variety of selective desalting precipitations. The colloid fraction was characterized by IR and NMR spectroscopy as N-acetylamino sugars. ?? 2000 American Chemical Society.

  8. Investigation of the heavy metal contamination of the sediments from the yellow river wetland nature reserve of zhengzhou, china.

    Science.gov (United States)

    Cheng, Q; Wang, W; Wang, H; Wang; Zhao, Z

    2012-01-01

    Heavy metal pollution in the sediment of the Yellow River draws wide attention in the recent years. The Yellow River Wetland Nature Reserve of Zhengzhou is one of the major wetlands of the river and located at the beginning of the lower reach. In this article, we aimed to investigate the degree and the sources of the metal pollution in the reserve. Metals as Cu, Pb, Cr, Cd and Mn in the sediment were monitored using flame atomic absorption spectrometry. The index of geo-accumulation (I(geo)) and the modified degree of contamination (mC(d)) were developed to evaluate individual metal pollution and overall enrichment impact of the elements. Compared with sediment quality guidelines, the effect of Cr and Pb are more serious than others. I(geo) values show Pb pollution are moderate at the Xinzhai, Langchenggang and Nansutan sites, and mC(d) analysis indicate the whole contamination at the Wantan, Langchenggang and Nansutan sites was low. Principal component analysis indicated that the first factor was Cu, Mn and Cd, mainly from soil erosion and the irrational use of phosphate fertilizers; the second Pb from fossil fuel burning; and the third Cr from weathering process. We conclude that Pb contamination is serious in the reserve, and the main sources of the metal are crude oil consumption and coal combustion of the brick kilns around. We also draw a conclusion that it is vital to evaluate contamination degree with both individual elements and overall average.

  9. Investigation of the Heavy Metal Contamination of the Sediments from the Yellow River Wetland Nature Reserve of Zhengzhou, China

    Science.gov (United States)

    Cheng, Q; Wang, W; Wang, H; Wang; Zhao, Z

    2012-01-01

    Background Heavy metal pollution in the sediment of the Yellow River draws wide attention in the recent years. The Yellow River Wetland Nature Reserve of Zhengzhou is one of the major wetlands of the river and located at the beginning of the lower reach. In this article, we aimed to investigate the degree and the sources of the metal pollution in the reserve. Methods: Metals as Cu, Pb, Cr, Cd and Mn in the sediment were monitored using flame atomic absorption spectrometry. The index of geo-accumulation (Igeo) and the modified degree of contamination (mCd) were developed to evaluate individual metal pollution and overall enrichment impact of the elements. Results: Compared with sediment quality guidelines, the effect of Cr and Pb are more serious than others. Igeo values show Pb pollution are moderate at the Xinzhai, Langchenggang and Nansutan sites, and mCd analysis indicate the whole contamination at the Wantan, Langchenggang and Nansutan sites was low. Principal component analysis indicated that the first factor was Cu, Mn and Cd, mainly from soil erosion and the irrational use of phosphate fertilizers; the second Pb from fossil fuel burning; and the third Cr from weathering process. Conclusion: We conclude that Pb contamination is serious in the reserve, and the main sources of the metal are crude oil consumption and coal combustion of the brick kilns around. We also draw a conclusion that it is vital to evaluate contamination degree with both individual elements and overall average. PMID:23113147

  10. Study on Law of Groundwater Evolution under Natural and Artificial Forcing with Case study of Haihe River Basin

    Science.gov (United States)

    You, Jinjun; Gan, Hong; Wang, Lin; Bi, Xue; Du, Sisi

    2010-05-01

    The evolution of groundwater is one of the key problems of water cycle study. It is a result of joint effect of natural condition and human activities, but until now the driving forces of groundwater system evolution were not fully understood due to the complexity of groundwater system structures and the uncertainty of affecting factors. Geology, precipitation and human activity are the main factors affecting the groundwater system evolution and interact each other, but the influence of such three factors on groundwater system are not clarified clearly on a macroscopic scale. The precipitation changes the volume of water recharge and the groundwater pumping effect the discharge of groundwater. Another important factor influencing balance of groundwater storage is the underlaying that affects the renewablility of groundwater. The underlaying is decided mainly by geological attributes but also influenced by human activited. The macroscopic environment of groundwater evolves under the natural and anthropic factors. This paper study the general law of groundwater evolution among the factors based on the case study in Haihe River Basin, a typical area with dramatic groundwater change under natural precipitation attenuation and gradually increase of water suuply. Haihe River Basin is located in north-China, covers an area of 320,041 km2 with over 40% plain areas. The plain area of Haihe Basin is densely populated with many large and medium-sized cities, including metropolis of Beijing and Tianjin, and concentrated irrigated areas, playing important roles in China's economy and food production. It is the unique basin where groundwater occupies majority of total water supply in China. Long-term groundwater over-exploitation causes a series of ecological and environmental problems that threats the sustainable development. In this paper, the historical process of groundwater balance in Haihe Basin is divided into three phases by decrease of rainfall and increase of water

  11. Natural and mining-related sources of dissolved minerals during low flow in the Upper Animas River Basin, southwestern Colorado

    Science.gov (United States)

    Wright, Winfield G.

    1997-01-01

    As part of the Clean Water Act of 1972 (Public Law 92-500), all States are required to establish water-quality standards for every river basin in the State. During 1994, the Colorado Department of Public Health and Environment proposed to the Colorado Water Quality Control Commission (CWQCC) an aquatic-life standard of 225 µg/L (micrograms per liter) for the dissolved-zinc concentration in the Animas River downstream from Silverton (fig.1). The CWQCC delayed implementation of this water-quality standard until further information was collected and a plan for the cleanup of abandoned mines was developed. Dissolved-zinc concentrations in this section of the river ranged from about 270 µg/L during high flow, when rainfall and snowmelt runoff dilute the dissolved minerals in the river (U.S. Geological Survey, 1996, p. 431), to 960 µg/L (Colorado Department of Public Health and Environment, written commun., 1996) during low flow (such as late summer and middle winter when natural springs and drainage from mines are the main sources for the streams). Mining sites in the basin were developed between about 1872 and the 1940's, with only a few mines operated until the early 1990's. For local governments, mining sites represent part of the Nation's heritage, tourists are attracted to the historic mining sites, and governments are obligated to protect the historic mining sites according to the National Historic Preservation Act (Public Law 89-665). In the context of this fact sheet, the term "natural sources of dissolved minerals" refers to springs and streams where no effect from mining were determined. "Mining-related sources of dissolved minerals" are assumed to be: (1 ) Water draining from mines , and (2) water seeping from mine-waste dump pile where the waste piles were saturated by water draining from mines. Although rainfall and snowmelt runoff from mine-waste piles might affect water quality in streams, work described in this fact sheet was done during low

  12. Preliminary flood-duration frequency estimates using naturalized streamflow records for the Willamette River Basin, Oregon

    Science.gov (United States)

    Lind, Greg D.; Stonewall, Adam J.

    2018-02-13

    In this study, “naturalized” daily streamflow records, created by the U.S. Army Corps of Engineers and the Bureau of Reclamation, were used to compute 1-, 3-, 7-, 10-, 15-, 30-, and 60-day annual maximum streamflow durations, which are running averages of daily streamflow for the number of days in each duration. Once the annual maximum durations were computed, the floodduration frequencies could be estimated. The estimated flood-duration frequencies correspond to the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent probabilities of their occurring or being exceeded each year. For this report, the focus was on the Willamette River Basin in Oregon, which is a subbasin of the Columbia River Basin. This study is part of a larger one encompassing the entire Columbia Basin.

  13. From natural to degraded rivers and back again. A test of restoration ecology theory and practice

    DEFF Research Database (Denmark)

    Feld, C.; Birk, S.; Hering, D.

    2011-01-01

    Extensive degradation of ecosystems, combined with the increasing demands placed on the goods and services they provide, is a major driver of biodiversity loss on a global scale. In particular, the severe degradation of large rivers, their catchments, floodplains and lower estuarine reaches has...... and elsewhere, mainly North America. Here, we focus on restoration of the physical properties (e.g. substrate composition, bank and bed structure) of river ecosystems to ascertain what has, and what has not, been learned over the last 20 years. First, we focus on three common types of restoration measures...... commonly used restoration measures, but the potential positive effects of such local habitat enhancement schemes were often likely to be swamped by larger-scale geomorphological and physico-chemical effects. Studies demonstrating long-term biological recovery due to habitat enhancement were notable...

  14. The importance of nature's invisible fabric: food web structure mediates modeled responses to river restoration

    Science.gov (United States)

    Bellmore, R.; Benjamin, J.; Newsom, M.; Bountry, J.; Dombroski, D.

    2016-12-01

    Restoration is frequently aimed at the recovery of target species, but also influences the larger food web in which these species participate. Effects of restoration on this broader network of organisms can influence target species both directly and indirectly via changes in energy flow through food webs. To help incorporate these complexities into river restoration planning we constructed a food web model that links river food web dynamics to in-stream physical habitat and riparian vegetation conditions. We present an application of this model to the Methow River, Washington (USA), a location of on-going restoration aimed at recovering salmon. Three restoration strategies were simulated: riparian vegetation restoration, nutrient augmentation via salmon carcass addition, and floodplain reconnection. To explore how food web structure mediates responses to these actions, we modified the food web by adding populations of invasive aquatic snails and nonnative fish. Simulations suggest that floodplain reconnection may be a better strategy than carcass addition and vegetation planting for improving conditions for salmon in this river segment. However, modeled responses were strongly sensitive to changes in the structure of the food web. The addition of invasive snails and nonnative fishes modified pathways of energy through the food web, which negated restoration improvements. This finding illustrates that forecasting responses to restoration may require accounting for the structure of food webs, and that changes in this structure—as might be expected with the spread of invasive species—could compromise restoration outcomes. By elucidating the direct and indirect pathways by which restoration affects target species, dynamic food web models can improve restoration planning by fostering a deeper understanding of system connectedness and dynamics.

  15. Natural and anthropogenic influences on a red-crowned crane habitat in the Yellow River Delta Natural Reserve, 1992-2008.

    Science.gov (United States)

    Wang, Hong; Gao, Jay; Pu, Ruiliang; Ren, Liliang; Kong, Yan; Li, He; Li, Ling

    2014-07-01

    This study aims to assess the relative importance of natural and anthropogenic variables on the change of the red-crowned crane habitat in the Yellow River Nature Reserve, East China using multitempopral remote sensing and geographic information system. Satellite images were used to detect the change in potential crane habitat, from which suitable crane habitat was determined by excluding fragmented habitat. In this study, a principal component analysis (PCA) with seven variables (channel flow, rainfall, temperature, sediment discharge, number of oil wells, total length of roads, and area of settlements) and linear regression analyses of potential and suitable habitat against the retained principal components were applied to explore the influences of natural and anthropogenic factors on the change of the red-crowned crane habitat. The experimental results indicate that suitable habitat decreased by 5,935 ha despite an increase of 1,409 ha in potential habitat from 1992 to 2008. The area of crane habitat changed caused by natural drivers such as progressive succession, retrogressive succession, and physical fragmentation is almost the same as that caused by anthropogenic forces such as land use change and behavioral fragmentation. The PCA and regression analyses revealed that natural factors (e.g., channel flow, rainfall, temperature, and sediment discharge) play an important role in the crane potential habitat change and human disturbances (e.g., oil wells, roads, and settlements) jointly explain 51.8 % of the variations in suitable habitat area, higher than 48.2 % contributed by natural factors. Thus, it is vital to reduce anthropogenic influences within the reserve in order to reverse the decline in the suitable crane habitat.

  16. Effects of recreational flow releases on natural resources of the Indian and Hudson Rivers in the Central Adirondack Mountains, New York, 2004-06

    Science.gov (United States)

    Baldigo, Barry P.; Mulvihill, C.I.; Ernst, A.G.; Boisvert, B.A.

    2011-01-01

    The U.S. Geological Survey (USGS), the New York State Department of Environmental Conservation (NYSDEC), and Cornell University carried out a cooperative 2-year study from the fall of 2004 through the fall of 2006 to characterize the potential effects of recreational-flow releases from Lake Abanakee on natural resources in the Indian and Hudson Rivers. Researchers gathered baseline information on hydrology, temperature, habitat, nearshore wetlands, and macroinvertebrate and fish communities and assessed the behavior and thermoregulation of stocked brown trout in study reaches from both rivers and from a control river. The effects of recreational-flow releases (releases) were assessed by comparing data from affected reaches with data from the same reaches during nonrelease days, control reaches in a nearby run-of-the-river system (the Cedar River), and one reach in the Hudson River upstream from the confluence with the Indian River. A streamgage downstream from Lake Abanakee transmitted data by satellite from November 2004 to November 2006; these data were used as the basis for developing a rating curve that was used to estimate discharges for the study period. River habitat at most study reaches was delineated by using Global Positioning System and ArcMap software on a handheld computer, and wetlands were mapped by ground-based measurements of length, width, and areal density. River temperature in the Indian and Hudson Rivers was monitored continuously at eight sites during June through September of 2005 and 2006; temperature was mapped in 2005 by remote imaging made possible through collaboration with the Rochester Institute of Technology. Fish communities at all study reaches were surveyed and characterized through quantitative, nearshore electrofishing surveys. Macroinvertebrate communities in all study reaches were sampled using the traveling-kick method and characterized using standard indices. Radio telemetry was used to track the movement and persistence of

  17. Phytosociology of planted and natural mangrove forests in the estuary of the Ostras River, Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Elaine Bernini

    2014-03-01

    Full Text Available The phytosociology of planted and natural mangrove forests were compared in the estuary of the Ostras River, Rio de Janeiro State, Brazil. Vegetation sampling was performed by the plot method, and the diameter at breast height (DBH and height of individuals > 1 m tall were recorded. The results indicated that the planted forest had lower average DBH and basal area and higher density of trunks in relation to natural forest. The distribution of individuals by height class and the distribution of stems per diameter class showed that the planted forest was younger. Laguncularia racemosa and Rhizophora mangle occurred in both forests, while Avicennia schaueriana was found only in the planted forest. Laguncularia racemosa showed greater dominance and relative density at all sites analyzed, probably because it is characteristic of sites with less marine influence and the fact that the estuary had been altered by human disturbance.

  18. Inhibition of hydroxyl radical reaction with aromatics by dissolved natural organic matter

    Science.gov (United States)

    Lindsey, M.E.; Tarr, M.A.

    2000-01-01

    Reaction of aromatic compounds with hydroxyl radical is inhibited by dissolved natural organic matter (NOM). The degree of inhibition is significantly greater than that expected based on a simple model in which aromatic compound molecules bound to NOM are considered to be unreactive. In this study, hydroxyl radical was produced at steady-state concentrations using Fenton chemistry (H2O2 + Fe2+ ??? Fe3+ + HO- + HO??). Suwannee River fulvic acid and humic acid were used as NOM. The most likely mechanism for the observed inhibition is that hydroxyl radical formation occurs in microenvironmental sites remote from the aromatic compounds. In addition to changes in kinetics, pyrene hydroxyl radical reaction also exhibited a mechanistic change in the presence of fulvic acid. The mechanism changed from a reaction that was apparently firstorder in pyrene to one that was apparently secondorder in pyrene, indicating that pyrene self-reaction may have become the dominant mechanism in the presence of fulvic acid. Dissolved NOM causes significant changes in the rate and mechanism of hydroxyl radical degradation of aromatic compounds. Consequently, literature rate constants measured in pure water will not be useful for predicting the degradation of pollutants in environmental systems. The kinetic and mechanistic information in this study will be useful for developing improved degradation methods involving Fenton chemistry.Reaction of aromatic compounds with hydroxyl radical is inhibited by dissolved natural organic matter (NOM). The degree of inhibition is significantly greater than that expected based on a simple model in which aromatic compounds molecules bounds to NOM are considered to be unreactive. In this study, hydroxyl radical was produced at steady-state concentrations using Fenton chemistry (H2O2 + Fe2+ ??? Fe3+ + HO- + HO??). Suwannee River fulvic acid and humic acid were used as NOM. The most likely mechanisms for the observed inhibition is that hydroxyl radical

  19. Scienti fi c Approaches and Methods in the Investigation of the Formation and Stability of Hydromorphic Natural Complexes of the Irtysh River Valley System (The Kazakhstan Part

    Directory of Open Access Journals (Sweden)

    A. G. Tsaregorodtseva

    2006-12-01

    Full Text Available The current geo-environmental situation of the Irtysh River valley system is connected with the high degree of control of the river drainage, which affects the functioning of its entire ecosystem and determines some morphological features of its channel. In the present work, the methodological approaches in the study of formation of the valley’s hydromorphic natural complexes are discussed, and the results of studies on the channel processes in the middle course of the Irtysh River are given.

  20. Small is beautiful: Upscaling from microscale laminar to natural turbulent rivers

    National Research Council Canada - National Science Library

    L. Malverti; E. Lajeunesse; F. Métivier

    2008-01-01

    ...) to investigate natural processes such as alluvial fans dynamics, knickpoints migration, and channel morphologies, such as meandering and braiding has become increasingly popular in recent years...

  1. Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

    Science.gov (United States)

    Yang, S. L.; Xu, K. H.; Milliman, J. D.; Yang, H. F.; Wu, C. S.

    2015-07-01

    The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003-2012) was 67 km3/yr (7%) lower than that of the previous 50 years (1950-2002), and 126 km3/yr less compared to the relatively wet period of pre-TGD decade (1993-2002). Most (60-70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950-1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors.

  2. Preliminary inventory and classification of indigenous afromontane forests on the Blyde River Canyon Nature Reserve, Mpumalanga, South Africa

    Directory of Open Access Journals (Sweden)

    Beck Hans T

    2004-08-01

    Full Text Available Abstract Background Mixed evergreen forests form the smallest, most widely distributed and fragmented biome in southern Africa. Within South Africa, 44% of this vegetation type has been transformed. Afromontane forest only covers 0.56 % of South Africa, yet it contains 5.35% of South Africa's plant species. Prior to this investigation of the indigenous forests on the Blyde River Canyon Nature Reserve (BRCNR, very little was known about the size, floristic composition and conservation status of the forest biome conserved within the reserve. We report here an inventory of the forest size, fragmentation, species composition and the basic floristic communities along environmental gradients. Results A total of 2111 ha of forest occurs on Blyde River Canyon Nature Reserve. The forest is fragmented, with a total of 60 forest patches recorded, varying from 0.21 ha to 567 ha in size. On average, patch size was 23 ha. Two forest communities – high altitude moist afromontane forest and low altitude dry afromontane forest – are identified. Sub-communities are recognized based on canopy development and slope, respectively. An altitudinal gradient accounts for most of the variation within the forest communities. Conclusion BRCNR has a fragmented network of small forest patches that together make up 7.3% of the reserve's surface area. These forest patches host a variety of forest-dependent trees, including some species considered rare, insufficiently known, or listed under the Red Data List of South African Plants. The fragmented nature of the relatively small forest patches accentuates the need for careful fire management and stringent alien plant control.

  3. Monitoring the Reproductive Success of Naturally Spawning Hatchery and Natural Spring Chinook Salmon in the Wenatchee River, 2008-2009 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Michael J.; Williamson, Kevin S. [Northwest Fisheries Science Center

    2009-05-28

    male fitness. For both sexes, run time had a smaller but still significant effect on fitness, with earlier returning fish favored. Spawning location within the river had a significant effect on fitness for both males and females, and for females explained most of the reduced fitness observed for hatchery fish in this population. While differences have been reported in the relative reproductive success of hatchery and naturally produced salmonids Oncorhynchus spp., factors explaining the differences are often confounded. We examined the spawning site habitat and redd structure variables of hatchery and naturally produced spring Chinook salmon O. tshawytscha of known size that spawned in two tributaries of the Wenatchee River. We controlled for variability in spawning habitat by limiting our analysis to redds found within four selected reaches. No difference in the instantaneous spawner density or location of the redd in the stream channel was detected between reaches. Within each reach, no difference in the fork length or weight of hatchery and naturally produced fish was detected. While most variables differed between reaches, we found no difference in redd characteristics within a reach between hatchery and naturally produced females. Correlation analysis of fish size and redd characteristics found several weak but significant relationships suggesting larger fish contract larger redds in deeper water. Spawner density was inversely related to several redd structure variables suggesting redd size may decrease as spawner density increases. Results should be considered preliminary until samples size and statistical power goals are reached in future years. Trends in relative reproductive success of hatchery and naturally produced spring Chinook salmon Oncorhynchus tshawytscha in the Wenatchee Basins suggest females that spawn in the upper reaches of the tributaries produced a great number of offspring compared to females that spawn in the lower reaches of the tributaries

  4. Reproductive indices in natural nests of giant Amazon river turtles Podocnemis expansa (Schweigger, 1812 (Testudines, Podocnemididae in the Environmental Protection Area Meanders of the Araguaia river

    Directory of Open Access Journals (Sweden)

    JRF Alves-Júnior

    Full Text Available A count was made of unhatched eggs and hatchling live and dead Podocnemis expansa turtles in 327 natural nests located on the beaches of the Environmental Protection Area (EPA Meanders of the Araguaia River, to determine the percentage of hatching (94.63%, non-hatching (5.37%, survival (94.24% and hatchling mortality (5.76%, and the average percentage of dead hatchlings during the 15 days in the nursery (0.97%. The mean number of hatchlings per nest was determined from the sum of the number of live and dead hatchlings divided by the total number of nests, while the mean number of eggs per nest was determined from the sum of live and dead hatchlings and unhatched eggs divided by the number of nests. These calculations yielded the following mean values: live hatchlings (88.98 ± 23.94, dead hatchlings (0.37 ± 0.93, unhatched eggs (5.07 ± 9.57, and total number of eggs (94.42 ± 21.30. The reproductive efficiency of the wild population of P. expansa can be affected by many environmental factors such as temperature, humidity and rainfall. In addition, man-made factors like the presence of chemicals in the water and the potential for infectious disease also have significant impact. The reproductive indices data obtained from this study are indispensable for future investigations of hatching anomalies.

  5. Forced migration, natural resource use and environmental change: the case of the Senegal River Valley.

    Science.gov (United States)

    Black, R; Sessay, M

    1998-03-01

    This study examined the environmental consequences of forced migration in the Matam and Podor regions of the Middle Senegal River Valley, Senegal. The analysis was based on a framework offered by Black (1994) and Leach (1992). This framework posits that: 1) refugees in a zone increase population/resource ratios and that resource accounting must consider the extent of renewable resources, the use of stocks of fixed capital, the extent to which resource use generates technological or socioeconomic changes which influence the ratios, and geographic area; 2) refugees tend to be "exceptional resource degraders"; and 3) refugees may ignore or be excluded from sustainable resource use regulations. The study area in the Senegal River Valley had Mauritanian refugees in 1989. The number of refugees was an estimated 67,800 in 1995, of which 47,000 were in the study area. The study region had experienced severe drought during the 1970s and early 1980s, had experienced acute pressure on the land and forest resources, and was experiencing conflicts between farmers and pastoralists. The Mauritanian migrants were not exceptional, but were a third wave of movements in the Middle Valley. The negative environmental impacts of forced migration were minimized by the scattered sites of settlement and the long history of contact between the two sides of the border. Refugees did not use resources in a more destructive or wasteful way than local populations and were not exceptional resource degraders. Environmental degradation is attributed to prior drought, actions by governmental and nongovernmental agencies, and actions by strangers from the south.

  6. Natural and anthropogenic emissions of N and P to the Parnaíba River Delta in NE Brazil

    Science.gov (United States)

    de Paula Filho, Francisco José; Marins, Rozane Valente; de Lacerda, Luiz Drude

    2015-12-01

    The Parnaiba River Delta is the largest open sea delta in the Americas, having a unique ecological importance for the conservation of wildlife and fisheries resources. However, little is known about the biogeochemistry of this ecosystem. This study estimates N and P emissions to the delta using emissions factors, calibrated with field samples and N and P concentrations in different compartments of the delta. The estimated loads totaled 14.517 t N year-1 and 8.748 t P year-1, indicating that anthropogenic N and P emissions outweigh natural emissions by approximately 5 and 10 times, respectively. The activities that contribute the most to this result are livestock farming, agriculture and the release of untreated domestic sewage. The flows of N and P from the estimated loads corresponded to 339 kg N km-2 year-1 and 204 kg P km-2 year-1, so the region can be classified as "meso-active" and "eury-active" with regard to the transfer of nutrients. These results are consistent with the coastal megabasin design (COSCATs) proposed by Meyback et al. (2006). This article presents a first approach to the calculation of an estimated annual emissions inventory of N and P for the lower basin of the Parnaíba River and its coastal region, representing an approach that has been satisfactorily used in assessing the sensitivity of estuarine systems in northeastern Brazil.

  7. Phenolics occurrence in surface water of the Dniester river basin (West Ukraine): natural background and industrial pollution

    Science.gov (United States)

    Sprynskyy, M.; Lebedynets, M.; Namieśnik, J.; Buszewski, B.

    2007-09-01

    Phenolics’ occurrence in surface water of the Dniester river basin (West Ukraine) with the definition of the natural background is studied. The main attention is given to the Upper Dniester basin and its tributary Stryj as the parts of the Sub-Carpathian oil- and gas province with the numerous objects of oil industry. The total amount of phenolics in water is studied. Phenolics’ concentrations from the first micrograms to the first milligrams per litre have been found in the surface water of the region. The natural background is defined as 0.012 mg l-1 for the areas out of the industrial influence. The anthropogenic part of phenolics is caused mainly by oil industry. The oil-producing objects provide the main phenolics’ releases in the region, due to the low protection level of mechanical facilities as well as to breach of technological norms on the oil-extracting objects. A man-made pollution of the basin water has a regional character and the natural self-purification processes seem to be insufficient for its neutralisation on the plains in particular.

  8. The regional nature of PM2.5 episodes in the upper Ohio River Valley.

    Science.gov (United States)

    Anderson, Richard R; Martello, Donald V; White, Curt M; Crist, Kevin C; John, Kuruvilla; Modey, William K; Eatough, Delbert J

    2004-08-01

    From October 1999 through September 2000, particulate matter (PM) with aerodynamic diameter > or =2.5 microm (PM2.5) mass and composition were measured at the National Energy Technology Laboratory Pittsburgh site, with a particle concentrator Brigham Young University-organic sampling system and a tapered element oscillating microbalance (TEOM) monitor. PM2.5 measurements had also been obtained with TEOM monitors located in the Pittsburgh, PA, area, and at sites in Ohio, including Steubenville, Columbus, and Athens. The PM data from all these sites were analyzed on high PM days; PM2.5 TEOM particulate mass at all sites was generally associated with transitions from locally high barometric pressure to lower pressure. Elevated concentrations occurred with transport of PM from outside the local region in advance of frontal passages as the local pressure decreased. During high-pressure periods, concentrations at the study sites were generally low throughout the study region. Further details related to this transport were obtained from surface weather maps and estimated back-trajectories using the hybrid single-particle Lagrangian integrated trajectory model associated with these time periods. These analyses indicated that transport of pollutants to the Pittsburgh site was generally from the west to the southwest. These results suggest that the Ohio River Valley and possible regions beyond act as a significant source of PM and its precursors in the Pittsburgh area and at the other regional sites included in this study.

  9. Natural streamflow simulation for two largest river basins in Poland: a baseline for identification of flow alterations

    Directory of Open Access Journals (Sweden)

    M. Piniewski

    2016-05-01

    Full Text Available The objective of this study was to apply a previously developed large-scale and high-resolution SWAT model of the Vistula and the Odra basins, calibrated with the focus of natural flow simulation, in order to assess the impact of three different dam reservoirs on streamflow using the Indicators of Hydrologic Alteration (IHA. A tailored spatial calibration approach was designed, in which calibration was focused on a large set of relatively small non-nested sub-catchments with semi-natural flow regime. These were classified into calibration clusters based on the flow statistics similarity. After performing calibration and validation that gave overall positive results, the calibrated parameter values were transferred to the remaining part of the basins using an approach based on hydrological similarity of donor and target catchments. The calibrated model was applied in three case studies with the purpose of assessing the effect of dam reservoirs (Włocławek, Siemianówka and Czorsztyn Reservoirs on streamflow alteration. Both the assessment based on gauged streamflow (Before-After design and the one based on simulated natural streamflow showed large alterations in selected flow statistics related to magnitude, duration, high and low flow pulses and rate of change. Some benefits of using a large-scale and high-resolution hydrological model for the assessment of streamflow alteration include: (1 providing an alternative or complementary approach to the classical Before-After designs, (2 isolating the climate variability effect from the dam (or any other source of alteration effect, (3 providing a practical tool that can be applied at a range of spatial scales over large area such as a country, in a uniform way. Thus, presented approach can be applied for designing more natural flow regimes, which is crucial for river and floodplain ecosystem restoration in the context of the European Union's policy on environmental flows.

  10. Natural streamflow simulation for two largest river basins in Poland: a baseline for identification of flow alterations

    Science.gov (United States)

    Piniewski, Mikołaj

    2016-05-01

    The objective of this study was to apply a previously developed large-scale and high-resolution SWAT model of the Vistula and the Odra basins, calibrated with the focus of natural flow simulation, in order to assess the impact of three different dam reservoirs on streamflow using the Indicators of Hydrologic Alteration (IHA). A tailored spatial calibration approach was designed, in which calibration was focused on a large set of relatively small non-nested sub-catchments with semi-natural flow regime. These were classified into calibration clusters based on the flow statistics similarity. After performing calibration and validation that gave overall positive results, the calibrated parameter values were transferred to the remaining part of the basins using an approach based on hydrological similarity of donor and target catchments. The calibrated model was applied in three case studies with the purpose of assessing the effect of dam reservoirs (Włocławek, Siemianówka and Czorsztyn Reservoirs) on streamflow alteration. Both the assessment based on gauged streamflow (Before-After design) and the one based on simulated natural streamflow showed large alterations in selected flow statistics related to magnitude, duration, high and low flow pulses and rate of change. Some benefits of using a large-scale and high-resolution hydrological model for the assessment of streamflow alteration include: (1) providing an alternative or complementary approach to the classical Before-After designs, (2) isolating the climate variability effect from the dam (or any other source of alteration) effect, (3) providing a practical tool that can be applied at a range of spatial scales over large area such as a country, in a uniform way. Thus, presented approach can be applied for designing more natural flow regimes, which is crucial for river and floodplain ecosystem restoration in the context of the European Union's policy on environmental flows.

  11. The nature of the bed load transport in the mouth of the river to the non-tidal sea (the Vistula River, Poland)

    Science.gov (United States)

    Lisimenka, Aliaksandr; Zwoliński, Zbigniew; Rudowski, Stanisław

    2015-04-01

    The Vistula, Poland's primary river, is the second largest river of the Baltic Sea Basin considering the average river flow and drainage area and one of the least regulated amongst large rivers in Europe. The main Vistula river mouth is a cross-cut artificial channel of about 3000 m length, 400 m width and up to 10 m depth. Results of three measurements campaigns which were carried out in the main Vistula river mouth in October 2013, March and June 2014 are presented. The area of interest was mapped using boat mounted high-resolution Reson Seabat 7101 multibeam echosounder system (MBES). River flow field information was obtained with Rio Grande 1200 kHz Acoustic Doppler Current Profiler (ADCP) along the designated 14 cross-section profiles at an interval of 250 m. Seismoacoustic measurements were carried out using Innomar SES-2000 parametric sub-bottom profiler along the longitudinal profiles at an interval of 30 m. At the end of each measurement campaign, 20-30 grab samples were collected in places chosen on the basis of current bathymetric map and were analyzed by sieving method. The obtained results have revealed comprehensive riverbed morphology of the river channel which is characterized by presence of multiple generations of small to large sandy dunes of various orientations, whose asymmetries indicate a general seaward migration. On the basis of newly developed method for quantitative analysis of subaqueous straight-crested rippled bottom roughness with using of the 2D Discrete Fourier Transform (2D DFT) algorithm which involved a calculation of low-order spectral moments, primary parameters of the observed bedforms such as crest-line spatial alignment, wavelength and height are determined. Depth-averaged flow velocities indicate spatial variability with increased flow velocities achieve up to 0.75 m/s in the mainstream. Analysis of the seismoacoustic data confirms seaward migration of the observed sand dunes and shows that, in general, dynamic sediment

  12. Natural radioactivity levels and associated health hazards from the terrestrial ecosystem in Rosetta branch of the River Nile, Egypt.

    Science.gov (United States)

    Abdellah, W M; Diab, H M; El-Kameesy, S U; Salama, E; El-Framawy, S

    2017-08-01

    Twenty soil and 25 sediment samples were collected from the banks and bottom of the River Nile in the surroundings of biggest cities located close to it. Natural radioactivity concentrations of (226)Ra, (232)Th and (40)K have been evaluated for all samples by means of γ spectrometric analysis. The radioactivity levels of soil and sediment samples fall within the internationally recommended values. Nevertheless, high natural background radiation zones are detected in the Kafr El-Zayat region due to the presence of a fertilizer factory, and in the Rosetta region due to the presence of black sand deposits. The absorbed dose rate, the γ index and excess life time cancer risk are calculated. High values for some of the radiation health parameters are detected in the Kafr El-Zayat and Rosetta regions representing a serious problem to public health because the soil and sediment are used as constructing material for buildings. Furthermore, the isotope analysis of uranium for representative collected sediment samples via α spectrometry showed average specific activities of 18.7 ± 3.6, 0.087 ± 0.0038 and 18.6 ± 3.8 Bq kg(-1) for (234)U, (235)U and (238)U, respectively. In general, these values confirm the balance in the isotopic abundance of U isotopes.

  13. Identification of humic acid-like and fulvic acid-like natural organic matter in river water using fluorescence spectroscopy.

    Science.gov (United States)

    Peiris, R H; Budman, H; Moresoli, C; Legge, R L

    2011-01-01

    Identifying the extent of humic acid (HA)-like and fulvic acid (FA)-like natural organic matter (NOM) present in natural water is important to assess disinfection by-product formation and fouling potential during drinking water treatment applications. However, the unique fluorescence properties related to HA-like NOM is masked by the fluorescence signals of the more abundant FA-like NOM. For this reason, it is not possible to accurately characterize HA-like and FA-like NOM components in a single water sample using direct fluorescence EEM analysis. A relatively simple approach is described here that demonstrates the feasibility of using a fluorescence excitation-emission matrix (EEM) approach for identifying HA-like and FA-like NOM fractions in water when used in combination with a series of pH adjustments and filtration steps. It is demonstrated that the fluorescence EEMS of HA-like and FA-like NOM fractions from the river water sample possessed different spectral properties. Fractionation of HA-like and FA-like NOM prior to fluorescence analysis is therefore proposed as a more reasonable approach.

  14. Impact of the Three Gorges Dam on the spawning stock and natural reproduction of Chinese sturgeon in Changjiang River, China

    Science.gov (United States)

    Gao, Xin; Lin, Pengcheng; Li, Mingzheng; Duan, Zhonghua; Liu, Huanzhang

    2016-09-01

    Chinese sturgeon ( Acipenser sinensis) is the flagship species of the Changjiang River. The migration route of this species is blocked by the first dam, the Gezhou Dam, and its reproduction is affected by the Three Gorges Dam (TGD), one of the largest dams in the world. We studied the impact of the impoundment of the Three Gorges Reservoir (TGR) since 2003 on the spawning stock and the natural reproduction of the Chinese sturgeon by using our monitoring data from 1997 to 2013. Results indicate that TGR impoundment has delayed the first spawning dates of the fish from middle-late October to late November, decreased the amount of spawning activities from twice to only once each year, and significantly reduced egg production. In particular, the fish did not demonstrate any spawning activities in 2013. Therefore, TGR impoundment significantly affects the natural reproduction of the fish downstream of the TGD. The spawning stock size of the fish is also predicted to further decrease in the future, which will lead to a risk of population extinction. Ecological regulations must be imposed on decreasing the water temperature to 20°C before mid-October and increasing water discharge downstream of the TGD in October to induce spawning of the Chinese sturgeon.

  15. DETECTING AND QUANTIFYING REDUCTIVE DECHLORINATION DURING MONITORED NATURAL ATTENUATION AT THE SAVANNAH RIVER CBRP SITE

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; JACK D. ISTOK, J; JENNIFER A. FIELD, J; ERIC RAES, E; Margaret Millings, M; AARON D. PEACOCK, A; Brian02 Looney, B

    2007-01-02

    Various attenuation mechanisms control the destruction, stabilization, and/or removal of contaminants from contaminated subsurface systems. Measuring the rates of the controlling attenuation mechanisms is a key to employing mass balance as a means to evaluate and monitor the expansion, stability and subsequent shrinkage of a contaminant plume. A team of researchers investigated the use of push-pull tests for measuring reductive dechlorination rates in situ at sites with low chlorinated solvent concentrations (<1 ppm). The field research also examined the synergistic use of a suite of geochemical and microbial assays. Previous push-pull tests applied to environmental remediation objectives focused on general hydrological characterization or on designing bioremediation systems by examining the response of the subsurface to stimulation. In this research, the push-pull technique was tested to determine its ''low-range'' sensitivity and uncertainty. Can these tests quantify relatively low attenuation rates representative of natural attenuation? The results of this research indicate that push-pull testing will be useful for measurement of in situ reductive dechlorination rates for chlorinated solvents at ''Monitored Natural Attenuation'' (MNA) sites. Further, using principal component analysis and other techniques, the research confirmed the usefulness of multiple lines of evidence in site characterization and in upscaling measurements made in individual wells--especially for sites where there is a geochemical gradient or varying geochemical regimes within the contaminant plume.

  16. Effects of natural and anthropogenic environmental changes on riverine fish assemblages: a framework for ecological assessment of rivers

    Directory of Open Access Journals (Sweden)

    Francisco Leonardo Tejerina-Garro

    2005-01-01

    Full Text Available Freshwater is a basic need for the mankind. Effective biological tools (ecologically based, efficient, rapid and consistently applicable to different ecological regions are needed to measure the "health" of rivers. Adapting such tools over a broad geographic area requires a detailed understanding of both the patterns of organisms assemblage composition and distribution within and among water bodies under natural conditions, and the nature of the major environmental gradients that cause or explain these patterns. A comprehensive review of the available litterature dealing with the identification of environmental factors structuring riverine fish assemblages under natural conditions permits to identify the most consistent ones.A água dos rios constituem um recurso básico para a humanidade. Instrumentos biológicos eficaces (com fundamento ecológico, eficientes, rápidos e aplicáveis à regiões ecologicamente diferentes são necessários para medir a "saúde" destes. Adaptar tais instrumentos a uma grande área geográfica requer uma compreensão detalhada dos padrões da composição da assembléia de organismos e da sua distribuição dentro e entre os corpos da água em condições naturais, e da natureza dos principais gradientes ambientais que causam ou explicam estes padrões. Uma revisão da literatura disponível pode ajudar a identificar os fatores ambientais mais consistentes que estruturam a assembléia de peixes de ambientes lóticos em condições naturais.

  17. Effects of natural organic matter properties on the dissolution kinetics of zinc oxide nanoparticles

    Science.gov (United States)

    Jiang, Chuanjia; Aiken, George R.; Hsu-Kim, Heileen

    2015-01-01

    The dissolution of zinc oxide (ZnO) nanoparticles (NPs) is a key step of controlling their environmental fate, bioavailability, and toxicity. Rates of dissolution often depend upon factors such as interactions of NPs with natural organic matter (NOM). We examined the effects of 16 different NOM isolates on the dissolution kinetics of ZnO NPs in buffered potassium chloride solution using anodic stripping voltammetry to directly measure dissolved zinc concentrations. The observed dissolution rate constants (kobs) and dissolved zinc concentrations at equilibrium increased linearly with NOM concentration (from 0 to 40 mg C L–1) for Suwannee River humic and fulvic acids and Pony Lake fulvic acid. When dissolution rates were compared for the 16 NOM isolates, kobs was positively correlated with certain properties of NOM, including specific ultraviolet absorbance (SUVA), aromatic and carbonyl carbon contents, and molecular weight. Dissolution rate constants were negatively correlated to hydrogen/carbon ratio and aliphatic carbon content. The observed correlations indicate that aromatic carbon content is a key factor in determining the rate of NOM-promoted dissolution of ZnO NPs. The findings of this study facilitate a better understanding of the fate of ZnO NPs in organic-rich aquatic environments and highlight SUVA as a facile and useful indicator of NOM interactions with metal-based nanoparticles.

  18. Dissolved organic matter reduces CuO nanoparticle toxicity to duckweed in simulated natural systems.

    Science.gov (United States)

    Rippner, Devin A; Green, Peter G; Young, Thomas M; Parikh, Sanjai J

    2017-12-11

    With increasing demand for recycled wastewater for irrigation purposes, there is a need to evaluate the potential for manufactured nanomaterials in waste water to impact crop production and agroecosystems. Copper oxide nanoparticles (CuO NPs) have previously been shown to negatively impact the growth of duckweed (Landoltia punctata) a model aquatic plant consumed by water fowl and widely found in agricultural runoff ditches in temperate climates. However, prior studies involving CuO NP toxicity to duckweed have focused on systems without the presence of dissolved organic matter (DOM). In the current study, duckweed growth inhibition was shown to be a function of aqueous Cu2+ concentration. Growth inhibition was greatest from aqueous CuCl2 and, for particles, increased with decreasing CuO particle size. The dissolution of CuO NPs in ½ Hoagland's solution was measured to increase with decreasing particle size and in the presence of Suwannee river humic and fulvic acids (HA; FA). However, the current results suggest that HA, and to a lesser extent, FA, decrease the toxicity of both CuO NPs and free ionized Cu to duckweed, likely by inhibiting Cu availability through Cu-DOM complex formation. Such results are consistent with changes to Cu speciation as predicted by speciation modeling software and suggest that DOM changes Cu speciation and therefore toxicity in natural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Changes in groundwater levels and the response of natural vegetation to transfer of water to the lower reaches of the Tarim River.

    Science.gov (United States)

    Xu, Hai-liang; Ye, Mao; Li, Ji-mei

    2007-01-01

    Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tarim River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiring higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in arid or semi-arid ecosystems.

  20. Natural versus anthropogenic dispersion of metals to the environment in the Wulik River area, western Brooks Range, northern Alaska

    Science.gov (United States)

    Kelley, K.D.; Hudson, T.

    2007-01-01

    Zinc-lead-silver mineral deposits in the Wulik River region, Alaska, contain an enormous accumulation of Zn. In addition to the giant deposits at Red Dog, at least nine other deposits are known. Natural weathering of these deposits has dispersed metals over a wide region over a long period of time (c. 10 000 years) through transport by stream and groundwater, stream sediments, formation of soils, and perhaps wind-blown atmospheric deposition from weathering of naturally enriched Pb-Zn surface deposits. Anthropogenic input also contributes metals to the environment. Mining of the Red Dog deposit, which began in 1989, produces fine-grained galena and sphalerite concentrates that are transported from the mine site by truck to a storage port facility. Wind-blown dispersion of concentrate dust along the road and around the port facility has been a source of local metal-rich surficial materials. Geochemical and mineralogical characteristics provide a means of distinguishing the natural versus anthropogenic metal sources. Soils over deposits have patterns of increasing metal contents with depth and proximity to the metal-bearing source, whereas ore concentrate dust is localized at the surface. The acidity produced by weathering of the sulphide deposits creates an environment in which elements such as Se and Mo are stable whereas Ca is not. Consequently, high Mo (up to 29 ppm) and Se (up to 17 ppm) and low Ca (<0.4%) concentrations characterize surficial materials near natural deposits. Acidic conditions also yield high Pb-Zn ratios (up to 70) because sphalerite is preferentially dissolved and Zn is mobilized during chemical weathering. In natural materials, secondary jarosite and anglesite are developed, and minor galena is etched and rounded due to a history of chemical and mechanical weathering. In contrast, dust-bearing samples have Pb/Zn ratios that are 0.4 or less, Ca contents are higher (0.2 to 3.6%), and Mo (<10 ppm) and Se (not detected) concentrations are low

  1. Influence of surface slope and roughness on the shape of river basins: a comparison between nature and numerical experiments

    Science.gov (United States)

    Yamato, Philippe; Castelltort, Sébastien; Willett, Sean

    2010-05-01

    The last two decades have been marked by a large amount of studies on the relative influences of climate and tectonics on landscape evolution. Coevally, considerable advances have been achieved in numerical modelling of landscape evolution. These have been particularly useful in testing hypotheses and scenarios of the potential controls and feedbacks between climate, tectonics and landscape evolution. However, our current knowledge of the physical processes of erosion in nature remains incomplete. Indeed, although the predictions of landscape evolution models are often insightful, they are also sometimes overlooked due to their lack of physical basis. In parallel with current field and experimental investigations on erosion processes, one way to tackle this problem is to compare simulated and natural landscapes. Then, this allows us to know how can one assess whether a simulated landscape is realistic in a long-standing problem in geomorphology. The scaling between stream length and upstream drainage area, a relation known as Hack's law (Hack, 1957) provides a constrain on the geometry of natural landscapes. It is however notoriously difficult to use this law to assess the goodness of a landscape evolution model since it must be regarded over a logarithmic range of scales (stream orders), which is usually not possible in landscape evolution models because of their resolution. The convergence angle, a measure of a basin's elongation (Castelltort et al., 2009) is a similar metrics of drainage basin shape. It is controlled by the slope and roughness of the undissected surface on which a new basin develops. This relation arises from analytical predictions of water flow over simple topography and is supported by data on median to large-scale natural networks. In the present study we investigate the influence of slope and surface roughness on the shape of river basins using the CASCADE code (Braun and Sambridge, 1997). Results show that the rules used to route water in

  2. Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Joan B. (Washington Department of Fish and Wildlife, Olympia, WA)

    2005-05-01

    In the spring of 2004 naturally produced smolts outmigrating from the Yakima River Basin were collected for the sixth year of pathogen screening. This component of the evaluation is to monitor whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Since 1999 the Cle Elum Hatchery has been releasing spring chinook salmon smolts into the upper Yakima River to increase natural production. In 1998 and 2000 through 2004 naturally produced smolts were collected for monitoring at the Chandler smolt collection facility on the lower Yakima River. Smolts were collected from mid to late outmigration, with a target of 200 fish each year. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia virus, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. Of these pathogens, only R. salmoninarum was detected in very low levels in the naturally produced smolts outmigrating in 2004. To date, only bacterial pathogens have been detected and prevalences have been low. There have been small variations each year and these changes are attributed to normal fluctuations in prevalence. All of the pathogens detected are widely distributed in Washington State.

  3. Revealing the natural complexity of fluvial morphology through 2D hydrodynamic delineation of river landforms

    Science.gov (United States)

    Wyrick, J. R.; Senter, A. E.; Pasternack, G. B.

    2014-04-01

    Fluvial landforms at the morphological-unit scale (~ 1-10 channel widths) are typically delineated and mapped either by breaking up the one-dimensional longitudinal profile with no accounting of lateral variations or by manually classifying surface water patterns and two-dimensional areal extents in situ or with aerial imagery. Mapping errors arise from user subjectivity, varying surface water patterns when the same area is observed at different discharges and viewpoints, and difficulty in creating a complete map with no gaps or overlaps in delineated polygons. This study presents a new theory for delineating and mapping channel landforms at the morphological-unit scale that eliminates in-field subjective decision making, adds full transparency for map users, and enables future systemic alterations without having to remap in the field. Delineation is accomplished through a few basic steps. First, near-census topographic and bathymetric data are used in a two-dimensional hydrodynamic model to create meter-scale depth and velocity rasters for a representative base flow. Second, expert judgment and local knowledge determine the number and nomenclature of landform types as well as the range of base flow depth and velocity over each type. This step does require subjectivity, but it is transparent and adjustable at any time. Third, the hydraulic landform classification is applied to hydraulic rasters to quickly, completely, and objectively map the planform pattern of laterally explicit landforms. Application of this theory will reveal the true natural complexity, yet systematic organization, of channel morphology.

  4. Trace Elements (Pb, Zn, Cu in Blood of Mute Swan (Cygnus olor from the Isonzo River Nature Reserve (Italy

    Directory of Open Access Journals (Sweden)

    G Isani*, M Cipone, G Andreani, E Carpenè, E Ferlizza, K Kravos1 and F Perco1

    2013-11-01

    Full Text Available Lead concentrations in blood of 45 specimens of mute swan from the molting area of the Isonzo River Mouth Nature Reserve (Italy were determined in two consecutive years (2006-2007, some birds were neck ringed to identify their homing behavior. The second sampling included whole body X-ray radiography and Cu and Zn plasma analyses to investigate the health impact of putative Pb exposure. X-ray images of all investigated specimens did not show any radiopacity due to the ingestion of metal bodies. Lead levels (0.08-0.44 g/ml were in the range of those reported for swans living in unpolluted or slightly polluted environments and excluded acute intoxication, as confirmed by clinical investigation. Zinc concentrations ranged between 2.93 and 7.59 g/ml and were one order of magnitude higher than Cu concentrations (0.21-0.42 g/ml. The negative correlation between Pb and Zn concentrations could be indicative of adverse health effects caused by chronic lead exposure. To our knowledge this is the first study reporting Pb, Zn and Cu blood levels, X-ray radiographies and data on the origin of swan populations.

  5. Effect of nutrients on the biodegradation of tributyltin (TBT) by alginate immobilized microalga, Chlorella vulgaris, in natural river water

    Energy Technology Data Exchange (ETDEWEB)

    Jin Jing [MOE Key Laboratory of Aquatic Product Safety, School of Marine Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong); Yang Lihua [MOE Key Laboratory of Aquatic Product Safety, School of Marine Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Chan, Sidney M.N. [Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong); Luan Tiangang, E-mail: cesltg@mail.sysu.edu.cn [MOE Key Laboratory of Aquatic Product Safety, School of Marine Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong); Li Yan [MOE Key Laboratory of Aquatic Product Safety, School of Marine Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Tam, Nora F.Y., E-mail: bhntam@cityu.edu.hk [Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong)

    2011-01-30

    The removal and degradation of tributyltin (TBT) by alginate immobilized Chlorella vulgaris has been evidenced in our previously published work. The present study was further to investigate the effect of spiked nutrient concentrations on the TBT removal capacity and degradation in the same alginate immobilized C. vulgaris. During the 14-d experiment, compared to the control (natural river water), the spiked nutrient groups (50% or 100% nutrients of the commercial Bristol medium as the reference, marked as 1/2N or 1N) showed more rapid cell proliferation of microalgae and higher TBT removal rate. Moreover, significantly more TBT was adsorbed onto the alginate matrix, but less TBT was taken up by the algal cells of the nutrient groups than that of the control. Mass balance data showed that TBT was lost as inorganic tin in the highest degree in 1N group, followed by 1/2N group and the least was in the control, but the relative abundance of the intermediate products of debutylation (dibutyltin and monobutyltin) were comparable among three groups. In conclusion, the addition of nutrients in contaminated water stimulated the growth and physiological activity of C. vulgaris immobilized in alginate beads and improved its TBT degradation efficiency.

  6. Infiltration from an impoundment for coal-bed natural gas, Powder River Basin, Wyoming: Evolution of water and sediment chemistry

    Science.gov (United States)

    Healy, R.W.; Rice, C.A.; Bartos, T.T.; McKinley, M.P.

    2008-01-01

    Development of coal-bed natural gas (CBNG) in the Powder River Basin, Wyoming, has increased substantially in recent years. Among environmental concerns associated with this development is the fate of groundwater removed with the gas. A preferred water-management option is storage in surface impoundments. As of January 2007, permits for more than 4000 impoundments had been issued within Wyoming. A study was conducted on changes in water and sediment chemistry as water from an impoundment infiltrated the subsurface. Sediment cores were collected prior to operation of the impoundment and after its closure and reclamation. Suction lysimeters were used to collect water samples from beneath the impoundment. Large amounts of chloride (12,300 kg) and nitrate (13,500 kg as N), most of which accumulated naturally in the sediments over thousands of years, were released into groundwater by infiltrating water. Nitrate was more readily flushed from the sediments than chloride. If sediments at other impoundment locations contain similar amounts of chloride and nitrate, impoundments already permitted could release over 48 x 106 kg of chloride and 52 x 106 kg of nitrate into groundwater in the basin. A solute plume with total dissolved solid (TDS) concentrations at times exceeding 100,000 mg/L was created in the subsurface. TDS concentrations in the plume were substantially greater than those in the CBNG water (about 2300 mg/L) and in the ambient shallow groundwater (about 8000 mg/L). Sulfate, sodium, and magnesium are the dominant ions in the plume. The elevated concentrations are attributed to cation-exchange-enhanced gypsum dissolution. As gypsum dissolves, calcium goes into solution and is exchanged for sodium and magnesium on clays. Removal of calcium from solution allows further gypsum dissolution.

  7. Water and Gender in Recreating Family Life with Maa Ganga: The Confluence of Nature and Culture in a North Indian River Pilgrimage

    Directory of Open Access Journals (Sweden)

    Catrien Notermans

    2016-11-01

    Full Text Available This article studies the meaning of water and gender in the North Indian pilgrimage to the sacred river Ganges. It joins the recent criticism in anthropology concerning the nature/culture divide and aims to transcend that divide by focusing on water, not apart from but as part of social life. Assuming that water’s sociality is gendered, the authors look at how both the river water—itself as a landscape material—and the pilgrims’ engagements with that water are gendered. Starting from the central question: How do men’s and women’s ritual engagements with the sacred female river water (mutually construct social life? The article investigates men’s and women’s ritual use of water at different sites. It focuses on more than the central pilgrimage shrine and links the sacred river site to people’s homes to know how the moving river water, collected by pilgrims at the shrine, is used in water rituals back home. Trying to counterbalance the male and scriptural bias which is prominent in the literature on Ganges’ pilgrimage sites, the pilgrimage is studied from the perspective of lived religion that takes people’s embodied practices and sensory experiences of nature into account as well as people’s everyday life. By showing how men’s and women’s rituals differ and complement each other, it argues that men’s rituals at the pilgrimage site and women’s rituals at home serve the recreation of the family in a paired way. The argument is built on longitudinal and multi-sited ethnographic fieldwork at the Ganges river shrine in Haridwar (Uttarakhand and pilgrims’ residence in Udaipur (Rajasthan.

  8. Natural, anthropogenic and fossil organic matter in river sediments and suspended particulate matter: a multi-molecular marker approach.

    Science.gov (United States)

    Micić, V; Kruge, M A; Köster, J; Hofmann, T

    2011-02-01

    Different classes of organic matter (OM) have been systematically investigated in sediments and suspended particulate matter (SPM) along the Danube River in order to understand causes of compositional changes. Analytical pyrolysis revealed the dominance of natural organic matter (NOM) in most of the samples. The predominance of aquatic biomass is evident mainly from the abundance of organonitrogen compounds and phenol distributions. As the river enters a forested gorge, the terrestrial component of the NOM in sediments is more significant. This is reflected in abundant methoxyphenols and a very high carbon preference index. SPM sample from a tributary shows a unique geochemical signature. It contains abundant carboxylic acids, amines, isoprenoids in the pyrolyzate, and is dominated by phytol and 24-methyl-cholesta-5,24(28)-dien-3β-ol in the extract, produced by a diatom bloom. Wax esters with a relatively high proportion of short, methyl-branched alkyl-chains appear together with abundant phytadienes and n-C(17) alkane in some samples, suggesting a microbial origin. Anthropogenic OM from runoff and atmospheric deposition was evident from a minor input of polycyclic aromatic hydrocarbons (PAHs) originating from mixed combustion sources. Multivariate analysis using PAH data led us to define simple molecular ratios to distinguish the PAH composition in sand and silty sediments. The newly defined ratios are the alkylated phenanthrenes and anthracenes ratio (APA; C(1)-C(3)/C(0)-C(3) phenanthrenes and anthracenes) and the PAH ring number ratio (RN; 5-6 ring parent PAHs/all parent PAHs). This demonstrates that alkylated, as well as 5-6 ring PAHs are better preserved in the finer than in coarser grained sediments. A ubiquitous, but minor input of petroleum-related contamination with a uniform composition was evident in all samples as revealed by the analysis of petroleum biomarkers. This study demonstrates that the investigation of different classes of riverine OM

  9. Efficiency of a nature-like bypass channel for restoring longitudinal connectivity for a river-resident population of brown trout.

    Science.gov (United States)

    Dodd, Jamie R; Cowx, Ian G; Bolland, Jonathan D

    2017-12-15

    Man-made, physical barriers have disrupted longitudinal connectivity for migratory fish in many river systems throughout the world for centuries. These barriers are considered to be a key reason for the decline of many fish species in river systems. To date, most research to ease movement of anadromous salmonids past such barriers to help dwindling populations has focused on the use of technical fishways. More recently emphasis has been placed on nature-like fishways to enable a wider range of fish species to bypass these barriers, but few studies have examined their efficacy. In this study, Passive Integrated Transponder (PIT) telemetry was used to assess the upstream-directed movements of 111 river-resident brown trout (length, 151-510-mm) into and through a 150-m long, nature-like bypass on the River Aire, England. Attraction (51%), entrance (86%), passage (78%) and exit (97%) efficiencies were high, and trout of a wide range of sizes entered and exited (197-510 mm) the pass across a wide range of flows (entrance = 3.55-67.44 m3s-1 and exit = 3.89-35.5 m3s-1). There was evidence that two trout inhabited the pass during the day, entering at sunrise and exiting at sunset. This information is important to improve understanding of fish pass performance, thus informing future best practice guidance of fish passage designs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Unconventional natural gas development did not result in detectable changes in water chemistry (within the South Fork Little Red River).

    Science.gov (United States)

    Austin, Bradley J; Scott, Erin; Massey, Leslie; Evans-White, Michelle A; Entrekin, Sally; Haggard, Brian E

    2017-05-01

    The Fayetteville Shale within north central Arkansas is an area of extensive unconventional natural gas (UNG) production. Recently, the Scott Henderson Gulf Mountain Wildlife Management Area (GMWMA) was leased from the state of Arkansas for NG exploration, raising concerns about potential impacts on water resources. From November 2010 through November 2014, we monitored four reaches of the South Fork Little Red River (SFLRR), within the GMWMA, establishing baseline physico-chemical characteristics prior to UNG development and assessing trends in parameters during and after UNG development. Water samples were collected monthly during baseflow conditions and analyzed for conductivity, turbidity, ions, total organic carbon (TOC), and metals. All parameters were flow-adjusted and evaluated for monotonic changes over time. The concentrations of all constituents measured in the SFLRR were generally low (e.g., nitrate ranged from <0.005 to 0.268 mg/l across all sites and sample periods), suggesting the SFLRR is of high water quality. Flow-adjusted conductivity measurements and sodium concentrations increased at site 1, while magnesium decreased across all four sites, TOC decreased at sites 1 and 3, and iron decreased at site 1 over the duration of the study. With the exception of conductivity and sodium, the physico-chemical parameters either decreased or did not change over the 4-year duration, indicating that UNG activities within the GMWMA have had minimal or no detectable impact on water quality within the SFLRR. Our study provides essential baseline information that can be used to evaluate water quality within the SFLRR in the future should UNG activity within the GMWMA expand.

  11. Distributions of air pollutants associated with oil and natural gas development measured in the Upper Green River Basin of Wyoming

    Directory of Open Access Journals (Sweden)

    R.A. Field

    2015-10-01

    Full Text Available Abstract Diffusive sampler monitoring techniques were employed during wintertime studies from 2009 to 2012 to assess the spatial distribution of air pollutants associated with the Pinedale Anticline and Jonah Field oil and natural gas (O&NG developments in the Upper Green River Basin, Wyoming. Diffusive sampling identified both the extent of wintertime ozone (O3 episodes and the distributions of oxides of nitrogen (NOx, and a suite of 13 C5+ volatile organic compounds (VOC, including BTEX (benzene, toluene, ethylbenzene and xylene isomers, allowing the influence of different O&NG emission sources to be determined. Concentration isopleth mapping of both diffusive sampler and continuous O3 measurements show the importance of localized production and advective transport. As for O3, BTEX and NOx mixing ratios within O&NG development areas were elevated compared to background levels, with localized hotspots also evident. One BTEX hotspot was related to an area with intensive production activities, while a second was located in an area influenced by emissions from a water treatment and recycling facility. Contrastingly, NOx hotspots were at major road intersections with relatively high traffic flows, indicating influence from vehicular emissions. Comparisons of observed selected VOC species ratios at a roadside site in the town of Pinedale with those measured in O&NG development areas show that traffic emissions contribute minimally to VOCs in these latter areas. The spatial distributions of pollutant concentrations identified by diffusive sampling techniques have potential utility for validation of emission inventories that are combined with air quality modeling.

  12. Application of unsupervised semivariogram textural classification of RADARSAT-1 data for the detection of natural oil seeps offshore the Amazon River mouth

    Energy Technology Data Exchange (ETDEWEB)

    de Miranda, F. P.; Bentz, C.M. [PETROBRAS, CENPES, CEGEQ (Brazil); Beisl, C.H. [Gorceix Foundation (Brazil); Lorenzetti, J.A.; de Araujo, C.E.S.; da Silva, C.L. [Oceansat (Brazil)

    1998-12-31

    The use of RADARSAT-1 imagery to identify oil slicks on the sea surface has proven to be one of the most cost-effective means of locating natural oil seeps which provide invaluable information to exploration geologists. CEGEQ has developed a satellite imagery processing technology to enhance the detection of oil seeps. A one year pilot project has been conducted in the deepwater mouth of the Amazon River in Brazil in which a fully operational image processing procedure was used to identify potential natural oil seeps based on sea-surface textures.

  13. Post-Release Attributes and Survival of Hatchery and Natural Fall Chinook Salmon in the Snake River, Annual Report 1998.

    Energy Technology Data Exchange (ETDEWEB)

    Tiffan, Kenneth F.; Rondorf, Dennis W.; Connor, William P.; Burge, Howard L.

    1999-12-01

    This report summarizes results of research activities conducted primarily in 1997 and 1998. This report communicates significant findings that will aid in the management and recovery of fall chinook salmon in the Columbia River Basin.

  14. River channel sensitivity to change in the context of human activities and natural factors: an 80-year record of channel morphodynamics on the lower Santa Clara River, Ventura County, California

    Science.gov (United States)

    Downs, P. W.; Dusterhoff, S. R.; Sears, W. A.

    2010-12-01

    River channel adjustments arise from the application of numerous catchment-based stressors operating at different space and time scales. Natural stressors include the impact of climatic phenomena and their inheritance; human stressors include both direct and indirect factors whose impacts have grown in magnitude and intensity during the Anthropocene, especially since about 1945. Consequently, the sensitivity of river channel morphodynamics is likely to have changed also, with implications for landform understanding and river management. Reconstructing channel morphodynamics during the Anthropocene requires interpreting multiple historical and secondary data sources to document changes at sufficient (i.e., reach-scale) resolution: for the 60-km lower Santa Clara River (LSCR), Ventura County, California, we used flow, sediment and precipitation records, repeat aerial photographs, LiDAR data, repeat topographic surveys, in-channel vegetation data, field observations, numerical modeling of high flow events, and narrative accounts. The catchment historical context since European-American settlement includes periods dominated by ranching and colonization (ca.1820-1890), irrigations and diversions (ca.1890-1955), dams and river modifications (1955-1990), and urban population growth (1990-present). Natural stressors were investigated based on the correlation of instantaneous flood peaks with annual rainfall records in this semi-arid setting. Successful prediction of the majority of gauged floods since about 1950 allows a flood sequence to be reconstructed back to 1873. Floods are clustered and of considerably greater magnitude in El Nino years of the El Nino-Southern Oscillation. The great majority of sediment transport thus occurs in El Nino years so that the dominant discharge is the largest discharge on record, in contrast to humid-region alluvial rivers. Responding to these stressors, the average width of the active channel bed has become narrower by almost 50% (1938

  15. Application of a multi-method approach in characterization of natural aquatic colloids from different sources along Huangpu River in Shanghai, China

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Caixia [School of Geography and Environment, Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, 99 Ziyang Road, Nanchang 330022 (China); Center for Environmental Nanoscience and Risk, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia 29208 (United States); State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China); Nie, Minghua [School of Geography and Environment, Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, 99 Ziyang Road, Nanchang 330022 (China); Lead, Jamie R. [Center for Environmental Nanoscience and Risk, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia 29208 (United States); Yang, Yi [State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China); Key Laboratory of Geographic Information Science of the Ministry of Education, Department of Geosciences, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062 (China); Zhou, Junliang [State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China); Merrifield, Ruth [Center for Environmental Nanoscience and Risk, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia 29208 (United States); Baalousha, Mohammed, E-mail: MBAALOUS@mailbox.sc.edu [Center for Environmental Nanoscience and Risk, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia 29208 (United States)

    2016-06-01

    Natural colloid properties and the impact of human activities on these properties are important considerations for studies seeking to understand the fate and transport of pollutants. In this study, the relationship between size and fluorescence properties of natural colloids from 4 different sources were quantified using a multi-method analytical approach including UV–visible and fluorescence spectroscopy, flow field flow fractionation (FlFFF) coupled online to fluorescence spectrometer, and atomic force microscopy (AFM). Results indicate that colloids from pristine natural river water have higher aromaticity and humification, higher fluorescent intensity, and smaller size compared to those from the rivers impacted by livestock. The majority of colloids are smaller than 10 nm in size as measured by AFM and FlFFF. Colloid size measured by FlFFF coupled to fluorescence spectroscopy increases in the order peak C (Ex/Em at 300–340/400–460 nm) < peak D (Ex/Em at 210–230/340–360 nm) < peak T (Ex/Em at 270–280/330–370 nm) < peak A (Ex/Em at 210–250/400–460 nm), revealing that optical properties such as fluorescence are correlated with size. This trend is confirmed by the principal component analysis, which demonstrates that the first principal component (PC1) reflecting colloid optical properties decrease with the increase in PC3 which is correlated to the colloid size. - Highlights: • Natural aquatic colloids from different sources were isolated using cross flow ultrafiltration. • Multi-method approach is applied for colloidal characterization. • Colloids in pristine natural river water showed higher aromaticity, humification, fluorescent intensity, and smaller sizes. • Optical properties of colloids are size-dependent.

  16. Is soil natural organic matter a sink or source for mobile radioiodine ( 129 I) at the Savannah River Site?

    Science.gov (United States)

    Xu, Chen; Zhang, Saijin; Ho, Yi-Fang; Miller, Eric J.; Roberts, Kimberly A.; Li, Hsiu-Ping; Schwehr, Kathleen A.; Otosaka, Shigeyoshi; Kaplan, Daniel I.; Brinkmeyer, Robin; Yeager, Chris M.; Santschi, Peter H.

    2011-10-01

    . These differences in iodination are due to different SOM molecular sizes, compositions, and availability of preferred iodination sites. 129I in the soil downstream from the contaminated site and near a wetland abruptly dropped below our detection limit (0.5 pCi- 129I/g-soil), which suggests that the high SOM in the plume soil around the 129I-contaminated F-Area might be a natural barrier to scavenge radioiodine released from the nuclear waste repository by forming organo-iodine compounds. Soil resuspension experiments showed that mobile 129I was mostly associated with a low average molecular weight amphiphilic organic carrier (13.5-15 kDa). SOM clearly behaves as a sink for iodine at the Savannah River Site F-Area. However, this work demonstrates that a small fraction of the SOM can also behave as a source, namely that a small fraction that may be readily dispersible under some environmental conditions and presumably release iodine in the organic-colloidal form. This radioiodinated organo-colloid likely can get into the groundwater through infiltration or surface runoff where it might migrate further into the wetlands. Results from this study provide the geochemical basis for future 129I migration controls, remediation, and/or land-groundwater management strategies.

  17. Floodplain development in engineered and natural settings determined with novel, high resolution 210-Pb geochronology: Insights from sedimentation studies along the lower Sacramento River, California

    Science.gov (United States)

    Aalto, R.; Singer, M. B.

    2008-12-01

    This presentation summarizes results from studies of floodplain sedimentation along the middle and lower Sacramento River that investigate processes using a new, high resolution methodology for 210Pb geochronology of 1-5 m floodplain cores. This approach accounts both for grain-size effects and radon ventilation and can resolve both deposition and erosional events. Therefore, it was possible to assess sedimentation over the past century within a wide array of sedimentary environments throughout the Sacramento Valley, where other techniques are limited. In particular, the Sacramento Valley has naturally low 210Pb activity due to its proximity to the Pacific Ocean, high rates of radon ventilation due to dry, porous floodplain sediment, and deposition of widely varying grain sizes - challenges that we have addressed with our enhanced methodology. The analytical approach affords a new ability to assess and directly compare dates and rates of sedimentation and erosion in disparate sedimentary environments throughout this complex fluvial dispersal system. We compare and contrast sediment deposition in engineered floodplains called bypasses, levied ancestral floodplains which serve as floodways during high flow, with sedimentation occurring in some remaining natural floodplains adjacent to the Sacramento River. We find that bypasses tend to accumulate sand and silt at their entrances, but that rates and textures decline rapidly with distance away from the channel. Essentially, a quasi-natural physical process of levee construction by advective overbank transport and deposition of sediment is operating (Singer and Aalto, ESPL, in press). These engineered floodways tend to siphon sediment out of the active channel, such that relatively low sedimentation rates prevail in floodplains and oxbow lakes within the active meander corridor that is bypassed. However, we document significant accumulation of fine-grained material in sedimentary sinks throughout floodplains upstream

  18. Summer co-existence of small-sized cyprinid and percid individuals in natural and impounded stretches of a lowland river: food niche partitioning among fishes.

    Science.gov (United States)

    Lik, J; Dukowska, M; Grzybkowska, M; Leszczyńska, J

    2017-04-01

    Due to changes of discharge regime downstream of a dam reservoir, an alluvial natural stretch of the Warta River changed to a macrophyte-dominated ecosystem. Large patches of submersed, aquatic macrophytes appeared in summer and their effect is analysed in this study. These patches contained enriched macroinvertebrate assemblages (epiphyton and benthos) and they were refuge for both zooplankton and young fishes released from the reservoir. Despite these altered conditions in this stretch, roach Rutilus rutilus, perch Perca fluviatilis and ruffe Gymnocephalus cernua dominated, as they did in the natural backwater. Fishes were sampled every 2 weeks from June to August, together with their food resources to assess the partitioning of the diet among small individuals of the three species in both stretches (the natural and affected ones). The aim of the analysis was to answer how animal food associated with water plants was partitioned between the species. In both stretches, G. cernua were primarily benthivorous, but epiphytic fauna, zooplankton and large-sized benthic chironomid larvae replaced lack of many large, benthic insects in the tailwater. Levins' food breath index decreased from 0·36 in the backwater to 0·29 in the tailwater. An opposite trend was observed for P. fluviatilis occurring among macrophytes. Perca fluviatilis were competitors of R. rutilus and took food not only in or on the river bed, but also in the water column. They ate zooplankton and epiphytic fauna and Levins' index increased from 0·32 to 0·44 in the tailwater. Rutilus rutilus fed on adult insects, algae and plant fragments in the natural stretch. In the tailwater, these food types were chiefly complemented by zooplankton. Despite this, the niche breadth of R. rutilus was similar at the two sites. Abundance of food associated with the macrophytes appeared to facilitate cohabitation in the abundant fish populations, but P. fluviatilis appeared to benefit the most in the altered river

  19. Ultraviolet irradiation effects incorporation of nitrate and nitrite nitrogen into aquatic natural organic matter

    Science.gov (United States)

    Thorn, Kevin A.; Cox, Larry G.

    2012-01-01

    One of the concerns regarding the safety and efficacy of ultraviolet radiation for treatment of drinking water and wastewater is the fate of nitrate, particularly its photolysis to nitrite. In this study, 15N NMR was used to establish for the first time that UV irradiation effects the incorporation of nitrate and nitrite nitrogen into aquatic natural organic matter (NOM). Irradiation of 15N-labeled nitrate in aqueous solution with an unfiltered medium pressure mercury lamp resulted in the incorporation of nitrogen into Suwannee River NOM (SRNOM) via nitrosation and other reactions over a range of pH from approximately 3.2 to 8.0, both in the presence and absence of bicarbonate, confirming photonitrosation of the NOM. The major forms of the incorporated label include nitrosophenol, oxime/nitro, pyridine, nitrile, and amide nitrogens. Natural organic matter also catalyzed the reduction of nitrate to ammonia on irradiation. The nitrosophenol and oxime/nitro nitrogens were found to be susceptible to photodegradation on further irradiation when nitrate was removed from the system. At pH 7.5, unfiltered irradiation resulted in the incorporation of 15N-labeled nitrite into SRNOM in the form of amide, nitrile, and pyridine nitrogen. In the presence of bicarbonate at pH 7.4, Pyrex filtered (cutoff below 290–300 nm) irradiation also effected incorporation of nitrite into SRNOM as amide nitrogen. We speculate that nitrosation of NOM from the UV irradiation of nitrate also leads to production of nitrogen gas and nitrous oxide, a process that may be termed photo-chemodenitrification. Irradiation of SRNOM alone resulted in transformation or loss of naturally abundant heterocyclic nitrogens.

  20. Role of natural organic matter in the mobility of aluminium ions in rivers in the Limousin region (France)

    OpenAIRE

    Guibaud, Gilles; Gauthier, Cécile; Ayele, Josiane

    2000-01-01

    International audience; In order to investigate, in the Limousin (France), the role of organic matter in aluminium mobility in soil towards rivers and its chemistry in water, three different A1 horizons of an acidic brown-earth soil planted with three different types of trees (chestnuts (Castanea sativa) over 100 years old, young Douglas fir (Pseudotsuga menzesii), and old Douglas fir) were selected, as well as five points on major rivers (Vienne, Vézère, Gartempe, Grande Creuse) in the area....

  1. Natural and anthropogenic factors affecting the structure of the benthic macroinvertebrate community in an effluent-dominated reach of the Santa Cruz River, AZ

    Science.gov (United States)

    Boyle, T.P.; Fraleigh, H.D.

    2003-01-01

    This study provides an assessment of the ecological conditions of a 46-km effluent-dominated stream section of the Santa Cruz River in the vicinity of the International Waste Water Treatment Plant, Nogales, AZ. We associated changes in the structure of the macroinvertebrate community to natural and anthropogenic chemical and physical variables using multivariate analysis. The analysis shows that biological criteria for effluent-dominated streams can be established using macroinvertebrate community attributes only with an understanding of the contribution of three classes of variables on the community structure: (1) low flow hydrological discharge as affected by groundwater withdrawals, treatment plant discharge, and subsurface geomorphology; (2) chemical composition of the treatment plant discharge and natural dilution; and (3) naturally produced floods resulting from seasonality of precipitation. ?? 2003 Elsevier Science Ltd. All rights reserved.

  2. Transport of oxidized multi-walled carbon nanotubes through silica based porous media: influences of aquatic chemistry, surface chemistry, and natural organic matter.

    Science.gov (United States)

    Yang, Jin; Bitter, Julie L; Smith, Billy A; Fairbrother, D Howard; Ball, William P

    2013-12-17

    This paper provides results from studies of the transport of oxidized multi-walled carbon nanotubes (O-MWCNTs) of varying surface oxygen concentrations under a range of aquatic conditions and through uniform silica glass bead media. In the presence of Na(+), the required ionic strength (IS) for maximum particle attachment efficiency (i.e., the critical deposition concentration, or CDC) increased as the surface oxygen concentration of the O-MWCNTs or pH increased, following qualitative tenets of theories based on electrostatic interactions. In the presence of Ca(2+), CDC values were lower than those with Na(+) present, but were no longer sensitive to surface oxygen content, suggesting that Ca(2+) impacts the interactions between O-MWCNTs and glass beads by mechanisms other than electrostatic alone. The presence of Suwannee River natural organic matter (SRNOM) decreased the attachment efficiency of O-MWCNTs in the presence of either Na(+) or Ca(2+), but with more pronounced effects when Na(+) was present. Nevertheless, low concentrations of SRNOM (organic carbon) were sufficient to mobilize all O-MWCNTs studied at CaCl2 concentrations as high as 10 mM. Overall, this study reveals that NOM content, pH, and cation type show more importance than surface chemistry in affecting O-MWCNTs deposition during transport through silica-based porous media.

  3. Deposition kinetics of bacteriophage MS2 on a silica surface coated with natural organic matter in a radial stagnation point flow cell.

    Science.gov (United States)

    Yuan, Baoling; Pham, Mai; Nguyen, Thanh H

    2008-10-15

    A quartz crystal microbalance (QCM) coupled with a radial stagnation point flow (RSPF) cell was used to study deposition kinetics of bacteriophage MS2 on silica surface coated with Suwannee River natural organic matter (SRNOM). Three stocks of MS2 stored in 1 mM NaHCO3, deionized (DI) water or phosphate buffer saline (PBS) solution were studied. MS2 stored in PBS solution were found to aggregate at all studied ionic strengths from 3 mM to 200 mM, while MS2 stored in DI water and bicarbonate solutions remained monodispersed. Isoelectric points of MS2 storedin PBS solution were lower than for those stored in DI water and 1 mM NaHCO3 solution. Nonrepulsive deposition rates of MS2 on silica surface coated with poly-L-lysine (PLL) were independent of ionic strength. In contrast MS2 deposition rates on bare silica surface or silica surface coated with SRNOM increased gradually and stabilized at an ionic strength of 60 mM. MS2 deposition rates on bare silica surface were higher than those on silica surface coated with SRNOM at low ionic strengths. Deposition rates on these two surfaces were similar at high ionic strengths. Experimental data suggest that electrostatic and steric interactions were the two main deposition mechanisms of MS2 on either bare silica or silica surface coated with SRNOM.

  4. Effects of source and seasonal variations of natural organic matters on the fate and transport of CeO2 nanoparticles in the environment.

    Science.gov (United States)

    Li, Zhen; Sahle-Demessie, Endalkachew; Aly Hassan, Ashraf; Pressman, Jonathan G; Sorial, George A; Han, Changseok

    2017-12-31

    Natural organic matter (NOM) affects the stability and transport of nanoparticles (NPs) in natural waters by modifying their physiochemical properties. Source location, and seasonal variations, influence their molecular, physical and electrical charge properties. To understand the variations of NOM on the mobilization of NPs, large volumes of water were collected from the Ohio River (OR) over winter and summer seasons and dissolved NOMs were concentrated. The chemical and structural differences of these NOMs were compared with the Suwannee River humic acid (SRHA) SRHA using 1H and 13C nuclear magnetic resonance spectroscopy, and Fourier transforms infrared (FTIR) spectroscopy. Thermal analysis and FTIR confirmed that differences in composition, structure, and functional groups are a result of SRHA fractionation compared to whole molecule OR-NOM. The influence of OR-NOMs on the surface charge of CeO2 NPs and the effects on the transport and retention in a three-phase (deposition-rinse-re-entrainment) sand-packed columns were investigated at CeO2 NPs initial concertation of 10ppm, pH6.8, increasing ionic strength (3, 5, and 10mM), retention time of 1min, and increasing NOM concentration (1, 5, and 10ppm). The summer OR-NOM showed higher stabilization and mobilization effect on the CeO2 than the winter NOM; while their effect was very different form the SRHA. The stabilization of NPs is attributed to both electrostatic and steric effects. The differences in the chemical structure of the complex and heterogeneous NOMs showed disparate reactivity and direct impact on CeO2-NPs stability. Using SRHA to study the effect of NOM for drinking water related assessment does not sufficiently represent the natural conditions of the environment. Published by Elsevier B.V.

  5. Chapter Three - From Natural to Degraded Rivers and Back Again: A Test of Restoration Ecology Theory and Practice

    NARCIS (Netherlands)

    Feld, C.K.; Birk, S.; Bradley, D.C.; Hering, D.; Kail, J.; Marzin, A.; Melcher, A.; Nemitz, D.; Pedersen, M.L.; Pletterbauer, F.; Pont, D.; Verdonschot, P.F.M.; Friberg, N.

    2011-01-01

    Extensive degradation of ecosystems, combined with the increasing demands placed on the goods and services they provide, is a major driver of biodiversity loss on a global scale. In particular, the severe degradation of large rivers, their catchments, floodplains and lower estuarine reaches has been

  6. Relative importance of natural and anthropogenic influences on the fresh surface water chemistry of the Hawkesbury-Nepean River, south-eastern Australia.

    Science.gov (United States)

    Markich, S J; Brown, P L

    1998-07-03

    Fresh surface waters from the Hawkesbury-Nepean River, the major river supplying water to the Sydney region in south-eastern Australia, were sampled monthly during 1991 and analysed for major ions (Na, K, Ca, Mg, Cl, SO4 and HCO3), nutrients (NO3 and PO4), organic carbon and trace metals (Al, Fe, Cu, Zn, Pb, Cd, Ni, Co and Mn). The chemical composition of the river during 1991 was consistent with other studies of the river from 1977 to 1996. The major ion composition in the river is predominantly influenced by sea-salt aerosols in rainwater (headwaters) and connate sea-salt in groundwater (mid-lower reaches), with a cationic dominance order of Na > Mg > Ca > K (equivalents) and an anionic order of Cl > HCO3 > SO4. This is typical of the headwaters of other permanent coastal rivers (freshwater) in south-eastern Australia with a similar catchment lithology. These results differ markedly from the most common natural major ion assemblages established for world rivers (i.e. Ca > Mg > Na > K and HCO3 > SO4 > Cl), which tend to be predominantly influenced by chemical weathering of rocks and minerals. The mean concentrations of major ions, nutrients, organic carbon and trace metals in the freshwater reaches of the Hawkesbury-Nepean River increased by factors of 2.5-4.4, 14-18, 2.2 and 1.6-11, respectively, with increasing distance from the headwaters. Increases in major ion concentrations are attributed mainly to the increasing influence of saline groundwater inflows from regions of Wianamatta shale. Conversely, concentrations of nutrients, organic carbon and trace metals (except Fe and Al) increased as a consequence of anthropogenic inputs, particularly point discharges from sewage treatment plants (i.e. showing distinct, but variable, concentration peaks), as well as diffuse urban and/or agricultural runoff during storm events. The temporal variability of the mean concentrations of all measured parameters in this study was related to variability in water discharge. The

  7. Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation Report 6 of 7, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Joan B. (Washington Department of Fish and Wildlife, Olympia, WA)

    2004-05-01

    In 1999 the Cle Elum Hatchery began releasing spring chinook salmon smolts into the upper Yakima River to increase natural production. Part of the evaluation of this program is to monitor whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. In 1998 and 2000 through 2003 naturally produced smolts were collected for monitoring at the Chandler smolt collection facility on the lower Yakima River. Smolts were collected from mid to late outmigration, with a target of 200 fish each year. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia virus, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. To date, only the bacterial pathogens have been detected and prevalences have been low. Prevalences have varied each year and these changes are attributed to normal fluctuation of prevalence. All of the pathogens detected are widely distributed in Washington State.

  8. Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Pearsons, Todd N.; Thomas, Joan B. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-01-01

    The change in pathogens prevalence to wild fish is probably the least studied ecological interaction associated with hatchery operations. In 1999, the Cle Elum Hatchery began releasing spring chinook smolts into the upper Yakima River to increase natural production. Part of the evaluation of this program is to evaluate whether introduction of hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Approximately 200 smolts were collected at the Chandler smolt collection facility on the lower Yakima River during 1998, 2000 and 2001 and monitored for specific pathogens. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. In addition, the fish were tested for Ceratomyxa shasta spores in 2001. Not all testing has been completed for every year, but to date, there have only been minimal changes in levels of the bacterial pathogens in the naturally produced smolts. At this point, due to the limited testing so far, these changes are attributed to normal fluctuation of prevalence.

  9. Simulating bank erosion over an extended natural sinuous river reach using a universal slope stability algorithm coupled with a morphodynamic model

    Science.gov (United States)

    Rousseau, Yannick Y.; Van de Wiel, Marco J.; Biron, Pascale M.

    2017-10-01

    Meandering river channels are often associated with cohesive banks. Yet only a few river modelling packages include geotechnical and plant effects. Existing packages are solely compatible with single-threaded channels, require a specific mesh structure, derive lateral migration rates from hydraulic properties, determine stability based on friction angle, rely on nonphysical assumptions to describe cutoffs, or exclude floodplain processes and vegetation. In this paper, we evaluate the accuracy of a new geotechnical module that was developed and coupled with Telemac-Mascaret to address these limitations. Innovatively, the newly developed module relies on a fully configurable, universal genetic algorithm with tournament selection that permits it (1) to assess geotechnical stability along potentially unstable slope profiles intersecting liquid-solid boundaries, and (2) to predict the shape and extent of slump blocks while considering mechanical plant effects, bank hydrology, and the hydrostatic pressure caused by flow. The profiles of unstable banks are altered while ensuring mass conservation. Importantly, the new stability module is independent of mesh structure and can operate efficiently along multithreaded channels, cutoffs, and islands. Data collected along a 1.5-km-long reach of the semialluvial Medway Creek, Canada, over a period of 3.5 years are used to evaluate the capacity of the coupled model to accurately predict bank retreat in meandering river channels and to evaluate the extent to which the new model can be applied to a natural river reach located in a complex environment. Our results indicate that key geotechnical parameters can indeed be adjusted to fit observations, even with a minimal calibration effort, and that the model correctly identifies the location of the most severely eroded bank regions. The combined use of genetic and spatial analysis algorithms, in particular for the evaluation of geotechnical stability independently of the hydrodynamic

  10. natural

    Directory of Open Access Journals (Sweden)

    Elías Gómez Macías

    2006-01-01

    Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.

  11. Effects of a natural dam-break flood on geomorphology and vegetation on the Elwha River, Washington, U.S.A.

    Science.gov (United States)

    Acker, S.A.; Beechie, T.J.; Shafroth, P.B.

    2008-01-01

    Ephemeral dams caused by landslides have been observed around the world, yet little is known about the effects of their failure on landforms and vegetation. In 1967, a landslide-dam-break flood in a pristine reach of the Elwha River valley filled the former channel and diverted the river. The reach is a reference site for restoration following the planned removal of dams on the river. We identified five surfaces on the 25 ha debris fan deposited by the flood. Based on tree ages and historic air photos, three of the surfaces formed in 1967, while two formed later. The surfaces varied in substrate (silt and sand, to boulders), and height above the river channel. Tree mortality resulted from tree removal and burial by sediment, the latter leaving snags and some surviving trees. Tree species composition was generally consistent within each surface. Dominant species included red alder (Alnus rubra) and Sitka willow (Salix sitchensis), alone or in combination, a combination of Douglas-fir (Pseudotsuga menziesii) and black cottonwood (Populus balsamifera ssp. trichocarpa), or a combination of alder and Cottonwood. There were significant differences between surfaces in stem density, basal area, and rate of basal area growth. The large degree of heterogeneity in forest structure, composition, and productivity within a relatively small floodplain feature is in part due to spatial variability in the intensity of a single disturbance event, and in part due to the occurrence of subsequent, smaller events. To recreate natural diversity of riparian forests may require mimicking the variety of physical and biotic habitats that a single, complex disturbance event may create.

  12. Natural born indicators: Great cormorant Phalacrocorax carbo (Aves: Phalacrocoracidae) as monitors of river discharge influence on estuarine ichthyofauna

    Science.gov (United States)

    Dias, Ester; Morais, Pedro; Leopold, Mardik; Campos, Joana; Antunes, Carlos

    2012-10-01

    The ecological traits of piscivorous marine birds have been acknowledged to reflect ecosystem changes. We used the great cormorant as our indicator species in the Minho estuary (NW-Iberian Peninsula, Europe) to assess the temporal variation of their diet and the factors that could influence that variation. Pellets were collected in a night roost, located centrally in the estuary, during two consecutive wintering periods (2005-2006 and 2006-2007). The great cormorant population showed a high degree of feeding plasticity and most of the variation in cormorants' diet was attributed to river discharge fluctuations. Overall, during periods of increased river discharge, marine and marine opportunistic species disappeared from diet, whereas freshwater species increased. The cormorants in this study were using a roost in the middle of the estuary, so they were facing a changing food base over time, in accordance to variation in river discharges. The birds did not keep their diet constant but rather took what became locally available, notwithstanding their broad foraging range. Therefore, we suggest that great cormorants may be considered good samplers of local ichthyofauna and thus, temporal variation in the local prey can be followed by analyzing cormorants' diet.

  13. Pathogen Screening of Naturally Produced Yakima River Spring Chinook Smolts; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Joan B. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-05-01

    In 1999 the Cle Elem Hatchery began releasing spring chinook smolts into the upper Yakima River for restoration and supplementation. This project was designed to evaluate whether introduction of intensively reared hatchery produced smolts would impact the prevalence of specific pathogens in the naturally produced spring chinook smolts. Increases in prevalence of any of these pathogens could negatively impact the survival of these fish. Approximately 200 smolts were collected at the Chandler smolt collection facility on the lower Yakima River during 1998, 2000 and 2001 and 130 smolts were collected in 2002 for monitoring for specific pathogens. The pathogens monitored were infectious hematopoeitic necrosis virus, infectious pancreatic necrosis virus, viral hemorrhagic septicemia, Flavobacterium psychrophilum, Flavobacterium columnare, Aeromonas salmonicida, Yersinia ruckeri, Edwardsiella ictaluri, Renibacterium salmoninarum and Myxobolus cerebralis. In addition the fish were tested for Ceratomyxa shasta spores in 2000 and 2001 (a correction from the 2001 report). To date, the only changes have been in the levels the bacterial pathogens in the naturally produced smolts and they have been minimal. These changes are attributed to normal fluctuation of prevalence.

  14. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

    Science.gov (United States)

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every MRB_E2RF1catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set is Estimated Mean Annual Natural Ground-Water Recharge in the Conterminous United States (Wolock, 2003). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  15. A long-term comparison of carbon sequestration rates in impounded and naturally tidal freshwater marshes along the lower Waccamaw River, South Carolina

    Science.gov (United States)

    Drexler, Judith Z.; Krauss, Ken W.; Sasser, M. Craig; Fuller, Christopher C.; Swarzenski, Christopher M.; Powell, Amber; Swanson, Kathleen M.; Orlando, James L.

    2013-01-01

    Carbon storage was compared between impounded and naturally tidal freshwater marshes along the Lower Waccamaw River in South Carolina, USA. Soil cores were collected in (1) naturally tidal, (2) moist soil (impounded, seasonally drained since ~1970), and (3) deeply flooded “treatments” (impounded, flooded to ~90 cm since ~2002). Cores were analyzed for % organic carbon, % total carbon, bulk density, and 210Pb and 137Cs for dating purposes. Carbon sequestration rates ranged from 25 to 200 g C m−2 yr−1 (moist soil), 80–435 g C m−2 yr−1 (naturally tidal), and 100–250 g C m−2 yr−1 (deeply flooded). The moist soil and naturally tidal treatments were compared over a period of 40 years. The naturally tidal treatment had significantly higher carbon storage (mean = 219 g C m−2 yr−1 vs. mean = 91 g C m−2 yr−1) and four times the vertical accretion rate (mean = 0.84 cm yr−1 vs. mean = 0.21 cm yr−1) of the moist soil treatment. The results strongly suggest that the long drainage period in moist soil management limits carbon storage over time. Managers across the National Wildlife Refuge system have an opportunity to increase carbon storage by minimizing drainage in impoundments as much as practicable.

  16. Identifying a breeding habitat of a critically endangered fish, Acheilognathus typus, in a natural river in Japan

    Science.gov (United States)

    Sakata, Masayuki K.; Maki, Nobutaka; Sugiyama, Hideki; Minamoto, Toshifumi

    2017-12-01

    Freshwater biodiversity has been severely threatened in recent years, and to conserve endangered species, their distribution and breeding habitats need to be clarified. However, identifying breeding sites in a large area is generally difficult. Here, by combining the emerging environmental DNA (eDNA) analysis with subsequent traditional collection surveys, we successfully identified a breeding habitat for the critically endangered freshwater fish Acheilognathus typus in the mainstream of Omono River in Akita Prefecture, Japan, which is one of the original habitats of this species. Based on DNA cytochrome B sequences of A. typus and closely related species, we developed species-specific primers and a probe that were used in real-time PCR for detecting A. typus eDNA. After verifying the specificity and applicability of the primers and probe on water samples from known artificial habitats, eDNA analysis was applied to water samples collected at 99 sites along Omono River. Two of the samples were positive for A. typus eDNA, and thus, small fixed nets and bottle traps were set out to capture adult fish and verify egg deposition in bivalves (the preferred breeding substrate for A. typus) in the corresponding regions. Mature female and male individuals and bivalves containing laid eggs were collected at one of the eDNA-positive sites. This was the first record of adult A. typus in Omono River in 11 years. This study highlights the value of eDNA analysis to guide conventional monitoring surveys and shows that combining both methods can provide important information on breeding sites that is essential for species' conservation.

  17. Post-Release Attributes and Survival of Hatchery and Natural Fall Chinook Salmon in the Snake River : Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Tiffan, Kenneth F.; Rondorf, Dennis W.

    2001-01-01

    This report summarizes results of research activities conducted in 1999 and years previous. In an effort to provide this information to a wider audience, the individual chapters in this report have been submitted as manuscripts to peer-reviewed journals. These chapters communicate significant findings that will aid in the management and recovery of fall chinook salmon in the Columbia River Basin. Abundance and timing of seaward migration of Snake River fall chinook salmon was indexed using passage data collected at Lower Granite Dam for five years. We used genetic analyses to determine the lineage of fish recaptured at Lower Granite Dam that had been previously PIT tagged. We then used discriminant analysis to determine run membership of PIT-tagged smolts that were not recaptured to enable us to calculate annual run composition and to compared early life history attributes of wild subyearling fall and spring chinook salmon. Because spring chinook salmon made up from 15.1 to 44.4% of the tagged subyearling smolts that were detected passing Lower Granite Dam, subyearling passage data at Lower Granite Dam can only be used to index fall chinook salmon smolt abundance and passage timing if genetic samples are taken to identify run membership of smolts. Otherwise, fall chinook salmon smolt abundance would be overestimated and timing of fall chinook salmon smolt passage would appear to be earlier and more protracted than is the case.

  18. Survival of natural populations of Austropotamobius pallipes in rivers in Bizkaia, Basque Country (North of Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    GARCÍA-ARBERAS L.

    2000-01-01

    Full Text Available Some relict populations of the native crayfish Austropotamobius pallipes have been located in rivers in Bizkaia, (Basque Country, Spain, and its population numbers and dynamics, and habitat conditions have been studied for three years. The first descriptive results are given in this paper. The native crayfish populations must be considered residual because of the disrupted area distribution and highly fluctuating demography of the species. Up to now, the species has been located in more than thirty fluvial areas of relatively high slope and shallow and good quality water. Population characteristics (sex ratio, length and weight relations and length frequency classes are studied in nineteen cases. Maximal relative population numbers are about 100 captures per hour ; these values are correlated to variables of conductivity, hardness, and concentrations of nitrates, nitrites, magnesium, potassium and ammonium. The degree of mineralization must reach a minimum level and, within the values found in the studied rivers, its increase favours the population of crayfish. Management measures to conserve native crayfish must include the protection and improvement of their habitat, prevention of access to it and to the commencement of a genetic study to palliate the phenomenon of endemism. It would also be highly recommendable to begin experimental restocking of riverbeds now without crayfish fauna and with apparently optimum conditions for the establishment of populations of autochthonous crayfish.

  19. Consequences of least tern (Sternula antillarum) microhabitat nest-site selection on natural and mechanically constructed sandbars in the Missouri River

    Science.gov (United States)

    Stucker, Jennifer H.; Buhl, Deborah A.; Sherfy, Mark H.

    2013-01-01

    Nest-habitat selection in colonial species has rarely been assessed at multiple spatial scales to evaluate its fitness consequences. Management for the federally endangered U.S. Interior population of Least Terns (Sternula antillarum) has focused on maintenance of breeding habitats, including mechanical construction of sandbars from dredged material. Least Terns are attracted to large areas of unvegetated substrate, yet small-scale habitat features are thought to trigger selection for nesting. We evaluated nest-scale habitat selection to determine (1) whether selection differs between constructed and natural sandbars and (2) the subsequent consequences of habitat selection on nest success. During 2006–2008, we examined 869 Least Tern nest sites on constructed and natural sandbars in the Missouri River for evidence of microhabitat selection at the nest in relation to habitat within the surrounding 3-m area. Least Tern nest sites had coarser and larger substrate materials at the nest, more debris, and less vegetation than the surrounding area. Nests in constructed habitats had a greater percentage of coarse substrates and less vegetation or debris than nests in naturally created habitats. Apparent nest success was 1.8× greater on constructed than on natural sandbars. Nest success was best predicted by models with two spatial scales of predictors, including substrates (nest) and vegetation and debris (nest or surrounding area). Our results indicate that Least Terns select nest microhabitat characteristics that are associated with wind- and water-scoured habitats, and that nest success increases when these habitats are selected.

  20. PLURALIZING NATURE

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    not necessary mean planning for a one common nature. As exemplified by the River Aire Re-naturalization Project (2002-2015), landscape architecture might provide an alternative approach to nature restoration that is more site specific and allows for multiple interpretations to coexist. In the presentation...

  1. Seasonal variation in the nature of DOM in a river and drinking water reservoir of a closed catchment.

    Science.gov (United States)

    Awad, John; van Leeuwen, John; Chow, Christopher W K; Smernik, Ronald J; Anderson, Sharolyn J; Cox, Jim W

    2017-01-01

    Dissolved organic matter (DOM) in surface waters used for drinking purposes can vary markedly in character depending on its source within catchments and the timing and intensity of rainfall events. Here we report the findings of a study on the character and concentration of DOM in waters collected during different seasons from Myponga River and Reservoir, South Australia. The character of DOM was assessed in terms of its treatability by enhanced coagulation and potential for disinfection by-product i.e. trihalomethane (THM) formation. During the wet seasons (winter and spring), water samples from the river had higher DOC concentrations (X¯: 21 mg/L) and DOM of higher average molecular weight (AMW: 1526 Da) than waters collected during the dry seasons (summer and autumn: DOC: 13 mg/L; AMW: 1385 Da). Even though these features led to an increase in the percentage removal of organics by coagulation with alum (64% for wet compared with 53% for dry season samples) and a lower alum dose rate (10 versus 15 mg alum/mg DOC removal), there was a higher THM formation potential (THMFP) from wet season waters (treated waters: 217 μg/L vs 172 μg/L). For reservoir waters, samples collected during the wet seasons had an average DOC concentration (X¯: 15 mg/L), percentage removal of organics by alum (54%), alum dose rates (13 mg/mg DOC) and THMFP (treated waters: 207 μg/L) that were similar to samples collected during the dry seasons (mean DOC: 15 mg/L; removal of organics: 52%; alum dose rate: 13 mg/mg DOC; THMFP: 212 μg/L for treated waters). These results show that DOM present in river waters and treatability by alum are highly impacted by seasonal environmental variations. However these in reservoir waters exhibit less seasonal variability. Storage of large volumes of water in the reservoir enables mixing of influent waters and stabilization of water quality. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  2. Contested Rivers

    DEFF Research Database (Denmark)

    Gorm Hansen, Louise Lyngfeldt

    explores translocal connections through ethnographic fieldwork at a global water conference and preliminary fieldwork at chosen locations on China's Nu River. The Nu River is one of the last undammed rivers in Asia and runs through China close to the Chinese-Burmese border, then flows into the Andaman Sea...... policy making, decision drivers and framing of large hydropower projects in China. Hydropower is a complex and interesting field to explore as the consequences go beyond the immediate locality and interacts with local as well as the global contexts. Inspired by Tsing (2003) and Zhan (2008) the paper...... and natural scientists and Chinese hydropower companies (to name a few). The paper maps different actors’ framing of the issue to gain a deeper understanding of the complexities of hydropower policymaking in China, as well as map the local consequences of global policymaking about large hydropower...

  3. Distribution of naturally occurring radioactive materials in sediments from the Ebro river reservoir in Flix (Southern Catalonia, Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Mola, M.; Palomo, M.; Penalver, A.; Aguilar, C. [Departament de Quimica Analitica i Quimica Organica, Universitat Rovira i Virgili, Marcelli Domingo s/n, 43007 Tarragona (Spain); Unitat de Radioquimica Ambiental i Sanitaria (URAIS), Consorci d' Aiguees de Tarragona (CAT), Ctra Nacional 340, km 1094, 43895 L' Ampolla (Spain); Borrull, F., E-mail: francesc.borrull@urv.cat [Departament de Quimica Analitica i Quimica Organica, Universitat Rovira i Virgili, Marcelli Domingo s/n, 43007 Tarragona (Spain); Unitat de Radioquimica Ambiental i Sanitaria (URAIS), Consorci d' Aiguees de Tarragona (CAT), Ctra Nacional 340, km 1094, 43895 L' Ampolla (Spain)

    2011-12-30

    Industrial waste containing radioactive isotopes (from U-decay series) was released into Ebro river basin due to the activity of a dicalcium phosphate (DCP) plant for a period of more than two decades. Gross alpha, gross beta, {sup 40}K, {sup 226}Ra and {sup 210}Pb activities were determined in several sludge samples taken at different depths from different points in the area of influence of the DCP plant located in Flix. Samples were collected from two different zones: one in front of the DCP plant and the second in front of a wastewater treatment plant installed several years after the DCP plant. The data obtained verify the influence of industrial DCP production on radioactivity levels present in the area.

  4. Determination of naturally occurring estrogenic hormones in cow's and river buffalo's meat by HPLC-FLD method

    Directory of Open Access Journals (Sweden)

    Yasser Shahbazi

    2016-07-01

    Full Text Available This study was performed to measure and compare the levels of steroid hormones [estrone (E1, 17β-estradiol (E2, and estriol (E3] and their conjugated metabolites in cow's and river buffalo's meat in two distinct follicular and luteal phases. Moreover, the possible effect of a heating process on steroid hormone concentration was also investigated. The collected meat (biceps femoris muscle samples were subjected to liquid extraction, enzymatical deconjugation, and C18 solid-phase extraction. Estrogens were analyzed using high performance liquid chromatography equipped with a fluorescence detector. In the follicular phase the levels of steroid hormones (E1 and E2 in either tested species were higher than the luteal phase. Moreover, in the present study, E1 concentration (free and deconjugated value, 16.2 ± 1.1 ng/L was found to be the highest phenolic estrogen in beef, while the dominant estrogen in muscle of river buffalo was E2 (free and deconjucated value, 23.3 ± 1.3 ng/L. The study revealed that animal species influenced the concentration of hormones (E1 and E2 in the samples. The heating process did not significantly change (p > 0.05 the levels of estrogens. The further findings of the present study showed that E3 (deconjugated form was only detected in the buffalo's meat (15.8 ± 1.9 ng/L. These data suggest that although meat is one of the valuable nutrient sources for humans, there are, however, increasing concerns about the safety of meat due to the excessive presence of steroid hormones.

  5. A historical case in the Bolivia-Brazil natural gas pipeline: slope on the Curriola River; Caso historico no Gasoduto Bolivia-Brasil: encosta no Rio Curriola

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Hudson Regis; Vasconcellos, Carlos Renato Aragonez de [Transportadora Brasileira Gasoduto Bolivia-Brasil, S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    The Bolivia-Brazil Natural Gas Pipeline has 2.593 kilometers since Rio Grande City in Bolivia until Canoas City, in south Brazil. The pipeline crosses a lot of types of geological fields and difficult topography. The south spread of the gas pipeline is the most interesting because of its hard topography combined with the variety of geological materials, such as, colluvium deposits and debris flow areas. Curriola River is located at the kilometer 408, north part of Parana State. In this area, the pipeline crosses slopes of 45 degrees of inclination. The down part of Curriola's slope is composed by a non-resistance material (clay and little rock blocks) with a high porosity. Every year, during the rainy seasons, tension cracks are observed evidencing the earth movement. The slope stability is above the minimum expected for pipeline operation. The aim of this paper is to present the site characterization of the Curriola River Slope, together with all the investigation made in order to supply the studies with condensed information for the slope stabilization. (author)

  6. Ground Beetles (Coleoptera: Carabidae and Some Other Invertebrates from the Managed Nature Reserves "Dolna Topchiya" and "Balabana" (Lower Valley of the River of Tundzha, Bulgaria

    Directory of Open Access Journals (Sweden)

    Teodora M. Teofilova

    2017-06-01

    Full Text Available The invertebrate fauna of the "Balabana" and "Dolna Topchiya" managed nature reserves is studied, with particular consideration to the ground beetles. The area of study is interesting from a biological point of view, as the Tundzha River constitutes a corridor of penetration of southern and thermophilic elements. On the other hand, the specifics of the territory predetermine the presence of many typically forest and some mountain species, as well as a lot of inhabitants of open biotopes, in particular – steppe forms. During the study, altogether 2041 specimens of carabid beetles belonging to 88 species are captured, as well as 76 other invertebrate species, some of which are with a conservation significance – new, endemic, rare, protected or endangered. Forty-six carabid species are reported for the first time for the Sakar-Tundzha region. Ground beetles are characterized and classified according to their zoogeographical belonging and the life forms they refer to.

  7. Coupled effects of natural and anthropogenic controls on seasonal and spatial variations of river water quality during baseflow in a coastal watershed of Southeast China.

    Directory of Open Access Journals (Sweden)

    Jinliang Huang

    Full Text Available Surface water samples of baseflow were collected from 20 headwater sub-watersheds which were classified into three types of watersheds (natural, urban and agricultural in the flood, dry and transition seasons during three consecutive years (2010-2012 within a coastal watershed of Southeast China. Integrating spatial statistics with multivariate statistical techniques, river water quality variations and their interactions with natural and anthropogenic controls were examined to identify the causal factors and underlying mechanisms governing spatiotemporal patterns of water quality. Anthropogenic input related to industrial effluents and domestic wastewater, agricultural activities associated with the precipitation-induced surface runoff, and natural weathering process were identified as the potential important factors to drive the seasonal variations in stream water quality for the transition, flood and dry seasons, respectively. All water quality indicators except SRP had the highest mean concentrations in the dry and transition seasons. Anthropogenic activities and watershed characteristics led to the spatial variations in stream water quality in three types of watersheds. Concentrations of NH(4(+-N, SRP, K(+, COD(Mn, and Cl- were generally highest in urban watersheds. NO3(-N Concentration was generally highest in agricultural watersheds. Mg(2+ concentration in natural watersheds was significantly higher than that in agricultural watersheds. Spatial autocorrelations analysis showed similar levels of water pollution between the neighboring sub-watersheds exhibited in the dry and transition seasons while non-point source pollution contributed to the significant variations in water quality between neighboring sub-watersheds. Spatial regression analysis showed anthropogenic controls played critical roles in variations of water quality in the JRW. Management implications were further discussed for water resource management. This research

  8. Emigration of Natural and Hatchery Naco x (Chinook salmon; Oncorhynchus tshawytscha) and Heeyey (Steelhead; Oncorhynchus mykiss) Smolts from the Imnaha River, Oregon from 5 October 2006 to 21 June 2007, Annual Report 2007.

    Energy Technology Data Exchange (ETDEWEB)

    Michaels, Brian; Espinosa, Neal (Nez Perce Tribe)

    2009-02-18

    This report summarizes the Nez Perce Tribe (NPT) Department of Fisheries Resources Management (DFRM) results for the Lower Snake River Compensation Plan (LSRCP) Hatchery Evaluation studies and the Imnaha River Smolt Monitoring Program (SMP) for the 2007 smolt migration from the Imnaha River, Oregon. These studies are closely coordinated and provide information about juvenile natural and hatchery spring/summer Naco x (Chinook Salmon; Oncorhynchus tshawytscha) and Heeyey (steelhead; O. mykiss) biological characteristics, emigrant timing, survival, arrival timing and travel time to the Snake River dams and McNary Dam (MCD) on the Columbia River. These studies provide information on listed Naco x (Chinook salmon) and Heeyey (steelhead) for the Federal Columbia River Power System (FCRPS) Biological Opinion (NMFS 2000). The Lower Snake River Compensation Plan program's goal is to maintain a hatchery production program of 490,000 Naco x (Chinook salmon) and 330,000 Heeyey (steelhead) for annual release in the Imnaha River (Carmichael et al. 1998, Whitesel et al. 1998). These hatchery releases occur to compensate for fish losses due to the construction and operation of the four lower Snake River hydroelectric facilities. One of the aspects of the LSRCP hatchery evaluation studies in the Imnaha River is to determine natural and hatchery Naco x (Chinook salmon) and Heeyey (steelhead) smolt performance, emigration characteristics and survival (Kucera and Blenden 1998). A long term monitoring effort was established to document smolt emigrant timing and post release survival within the Imnaha River, estimate smolt survival downstream to McNary Dam, compare natural and hatchery smolt performance, and collect smolt-to-adult return information. This project collects information for, and is part of, a larger effort entitled Smolt Monitoring by Federal and Non-Federal Agencies (BPA Project No. 198712700). This larger project provides data on movement of smolts out of major

  9. POSTCLOSURE GROUNDWATER REMEDIATION AND MONITORING AT THE SANITARY LANDFILL, SAVANNAH RIVER SITE TRANSITIONING TO MONITORED NATURAL ATTENUATION

    Energy Technology Data Exchange (ETDEWEB)

    Ross, J; Walt Kubilius, W; Thomas Kmetz, T; D Noffsinger, D; Karen M Adams, K

    2006-11-17

    Resource Conservation and Recovery Act (RCRA) requirements for hazardous waste facilities include 30 years of post-closure monitoring. The use of an objective-based monitoring strategy allows for a significant reduction in the amount of groundwater monitoring required, as the groundwater remediation transitions from an active biosparging system to monitored natural attenuation. The lifecycle of groundwater activities at the landfill has progressed from detection monitoring and plume characterization, to active groundwater remediation, and now to monitored natural attenuation and postclosure monitoring. Thus, the objectives of the groundwater monitoring have changed accordingly. Characterization monitoring evaluated what biogeochemical natural attenuation processes were occurring and determined that elevated levels of radium were naturally occurring. Process monitoring of the biosparging system required comprehensive sampling network up- and down-gradient of the horizontal wells to verify its effectiveness. Currently, the scope of monitoring and reporting can be significantly reduced as the objective is to demonstrate that the alternate concentration limits (ACL) are being met at the point of compliance wells and the maximum contaminant level (MCL) is being met at the surface water point of exposure. The proposed reduction is estimated to save about $2M over the course of the remaining 25 years of postclosure monitoring.

  10. The consequences of trampling disturbance in two vegetation types at the Wyoming Nature Conservancy's Sweetwater River project area

    Science.gov (United States)

    Christopher A. Monz; Tami Pokorny; Jerry Freilich; Sharon Kehoe; Dayna Ayers-Baumeister

    2000-01-01

    The consequences of human trampling disturbance on two codominant vegetation types at the Wyoming Nature Conservancy’s Sweetwater Preserve were examined. Small trampling lanes (1.5m x 0.5m) were established in both vegetation types and trampling treatments ranging from 0 to 800 passes were applied. Artemisia (Sagebrush) vegetation type was more...

  11. EPA Settles with Natural Gas Company for Oil Spill in Ohio River Tributary in Marshall Co., W. Va.

    Science.gov (United States)

    PHILADELPHIA (March 23, 2016) - The U.S. Environmental Protection Agency announced today that Williams Ohio Valley Midstream, the owner and operator of a natural gas pipe line in Moundsville, W. Va. has paid a $14,440 penalty to settle an all

  12. Mechanisms of goethite dissolution in the presence of desferrioxamine B and Suwannee River fulvic acid at pH 6.5

    Science.gov (United States)

    Stewart, Angela G.; Hudson-Edwards, Karen A.; Dubbin, William E.

    2013-08-01

    Siderophores are Fe3+ specific low MW chelating ligands secreted by micro-organisms in response to Fe stress. Low MW organic acids such as oxalate have been shown to enhance siderophore mediated dissolution of Fe3+ oxides. However, the effect of fulvic acid presence on siderophore function remains unknown. We used batch dissolution experiments to investigate Fe release from goethite in the goethite-fulvic acid-desferrioxamine B (goethite-SRFA-DFOB) ternary system. Experiments were conducted at pH 6.5 while varying reagent addition sequence. FTIR and UV-Vis spectroscopy were employed to characterise the Fe-DFOB, Fe-SRFA and DFOB-SRFA complexes. Iron released from goethite in the presence of SRFA alone was below detection limit. In the presence of both SRFA and DFOB, dissolved Fe increased with reaction time, presence of the DFOB-SRFA complex, and where SRFA was introduced prior to DFOB. FTIR data show that in the ternary system, Fe3+ is complexed primarily to oxygen of the DFOB hydroxamate group, whilst the carboxylate Cdbnd O of SRFA forms an electrostatic association with the terminal NH3+ of DFOB. We propose that SRFA sorbed to goethite lowers the net positive charge of the oxide surface, thus facilitating adsorption of cationic DFOB and subsequent Fe3+ chelation and release. Furthermore, the sorbed SRFA weakens Fe-O bonds at the goethite surface, increasing the population of kinetically labile Fe. This work demonstrates the positive, though indirect role of SRFA in increasing the bioavailability of Fe3+.

  13. Natural Propagation and Habitat Improvement, Volume I, Oregon, Supplement C, White River Habitat Inventory, 1983 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Heller, David

    1984-04-01

    More than 130 miles of stream fish habitat was inventoried and evaluated on the Mt. Hood National Forest during the first year of this multi-year project. First year tasks included field inventory and evaluation of habitat conditions on the White River and tributary streams thought to have the highest potential for supporting anadromous fish populations. All streams inventoried were located on the Mt. Hood National Forest. The surveyed area appears to contain most of the high quality anadromous fish habitat in the drainage. Habitat conditions appear suitable for steelhead, coho, and chinook salmon, and possibly sockeye. One hundred and twenty-four miles of potential anadromous fish habitat were identifed in the survey. Currently, 32 miles of this habitat would be readily accessible to anadromous fish. An additional 72 miles of habitat could be accessed with only minor passage improvement work. About 20 miles of habitat, however, will require major investment to provide fish passage. Three large lakes (Boulder, 14 acres; Badger, 45 acres; Clear, 550 acres) appear to be well-suited for rearing anadromous fish, although passage enhancement would be needed before self-sustaining runs could be established in any of the lakes.

  14. Synthesis, characterization, and application of modified silica in the removal and preconcentration of lead ions from natural river water

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Guilherme; Padilha, Pedro Magalhaes; Castro, Gustavo Rocha [Univ. Estadual Paulista, Departamento de Quimica e Bioquimica, IB/UNESP, Botucatu, SP (Brazil); Caetano, Laercio [Univ. Estadual Paulista, Departamento de Fisica e Quimica, FEIS/UNESP, Ilha Solteira, SP (Brazil); Castro, Renata S.D. [Univ. Estadual Paulista, Departamento de Fitotecnia, Tecnologia de Alimentos e Socio Economia, FEIS/UNESP, Ilha Solteira, SP (Brazil)

    2011-04-15

    This paper describes the synthesis, modification, and application of modified silica for the removal of lead ions from aqueous medium. The modification reaction provided a reduction in surface are from 737 to 399 m{sup 2} g{sup -1}, which was attributed to the 4-amine-2-mercaptopyrimidine molecule attachment onto its surface. The characterization through FTIR spectra demonstrated bands at 3347 cm{sup -1} assigned to N-H stretching vibrations and the absence of thiol bands at 2600 e 2547 cm{sup -1} at Si-mod spectrum is an indicative that the attachment occurred via SH groups. The linearization of adsorption isotherm data through the modified Langmuir equation resulted in a maximum adsorption capacity of 2.9 {mu}mol g{sup -1}. The material was applied in a continuous flow system in the preconcentration of water samples from Parana River and the results were in agreement with metal concentration determined directly through atomic absorption spectrometry with graphite furnace. The method validation was performed through analysis of water standard reference material (1643e), which also presented a 7.2-fold enrichment factor. (orig.)

  15. Potencial for natural forest regeneration from seed bank in an upper Paraná river floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Campos João Batista

    2003-01-01

    Full Text Available The historical process of deforestation was analyzed to evaluate the regeneration potential of forests from soil seed bank of Porto Rico island (53° 15'W and 22° 45'S in the upper Paraná river floodplain. Remnant forest fragments were identified and measured and the structure of arboreous vegetation and the composition of the seed bank of the forests and grassland of the island were evaluated. Results showed a fast process of deforestation with critical levels of forest: the remaining twice fragments represented only 5.98% of the total surface of the island. Disturbance by cattle raised on the island continuously degraded the fragments (backward succession, while expansion of areas with pasture favored severe impoverishment of the seed banks flora. The latter factor, soil compaction, and characteristics of seeds of existing arboreous species in the bank suggested that the immediate reestablishment of vegetation was more conditioned to introduction processes of seeds (by rain and ''flood seed'' than by stock of seeds in the bank.

  16. Natural-color and color-infrared image mosaics of the Colorado River corridor in Arizona derived from the May 2009 airborne image collection

    Science.gov (United States)

    Davis, Philip A.

    2013-01-01

    The Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey (USGS) periodically collects airborne image data for the Colorado River corridor within Arizona (fig. 1) to allow scientists to study the impacts of Glen Canyon Dam water release on the corridor’s natural and cultural resources. These data are collected from just above Glen Canyon Dam (in Lake Powell) down to the entrance of Lake Mead, for a total distance of 450 kilometers (km) and within a 500-meter (m) swath centered on the river’s mainstem and its seven main tributaries (fig. 1). The most recent airborne data collection in 2009 acquired image data in four wavelength bands (blue, green, red, and near infrared) at a spatial resolution of 20 centimeters (cm). The image collection used the latest model of the Leica ADS40 airborne digital sensor (the SH52), which uses a single optic for all four bands and collects and stores band radiance in 12-bits. Davis (2012) reported on the performance of the SH52 sensor and on the processing steps required to produce the nearly flawless four-band image mosaic (sectioned into map tiles) for the river corridor. The final image mosaic has a total of only 3 km of surface defects in addition to some areas of cloud shadow because of persistent inclement weather during data collection. The 2009 four-band image mosaic is perhaps the best image dataset that exists for the entire Arizona part of the Colorado River. Some analyses of these image mosaics do not require the full 12-bit dynamic range or all four bands of the calibrated image database, in which atmospheric scattering (or haze) had not been removed from the four bands. To provide scientists and the general public with image products that are more useful for visual interpretation, the 12-bit image data were converted to 8-bit natural-color and color-infrared images, which also removed atmospheric scattering within each wavelength-band image. The conversion required an evaluation of the

  17. Assessing climate-change risks to cultural and natural resources in the Yakima River Basin, Washington, USA

    Science.gov (United States)

    Hatten, James R.; Waste, Stephen M.; Maule, Alec G.

    2014-01-01

    We provide an overview of an interdisciplinary special issue that examines the influence of climate change on people and fish in the Yakima River Basin, USA. Jenni et al. (2013) addresses stakeholder-relevant climate change issues, such as water availability and uncertainty, with decision analysis tools. Montag et al. (2014) explores Yakama Tribal cultural values and well-being and their incorporation into the decision-making process. Graves and Maule (2012) simulates effects of climate change on stream temperatures under baseline conditions (1981–2005) and two future climate scenarios (increased air temperature of 1 °C and 2 °C). Hardiman and Mesa (2013) looks at the effects of increased stream temperatures on juvenile steelhead growth with a bioenergetics model. Finally, Hatten et al. (2013) examines how changes in stream flow will affect salmonids with a rule-based fish habitat model. Our simulations indicate that future summer will be a very challenging season for salmonids when low flows and high water temperatures can restrict movement, inhibit or alter growth, and decrease habitat. While some of our simulations indicate salmonids may benefit from warmer water temperatures and increased winter flows, the majority of simulations produced less habitat. The floodplain and tributary habitats we sampled are representative of the larger landscape, so it is likely that climate change will reduce salmonid habitat potential throughout particular areas of the basin. Management strategies are needed to minimize potential salmonid habitat bottlenecks that may result from climate change, such as keeping streams cool through riparian protection, stream restoration, and the reduction of water diversions. An investment in decision analysis and support technologies can help managers understand tradeoffs under different climate scenarios and possibly improve water and fish conservation over the next century.

  18. SPATIAL VARIABILITY OF SOILS ELECTRICAL CONDUCTIVITY WITHIN ARENA OF THE RIVER DNEPR VALLEY (TERRITORY OF THE NATURAL RESERVE "DNIPROVSKO-ORILSKY"

    Directory of Open Access Journals (Sweden)

    O. V. Zhukov

    2016-06-01

    Full Text Available Within experimental range on arena of the river Dnepr in natural reserve "Dneprovsko-Orelsky" in 241 points electric conductivity of soil has been measured by two ways: in a condition of natural humidity and in a condition of a full moisture capacity. It is established that on the average electrical conductivity makes 0.068±0.002 and 0.267±0.014 dSm/m accordingly. As a result of the carried out research by us the established procedure which allows to transform point objects which contain the information on electric conductivity of soil in continual (raster layer on the basis of established regression dependences of an investigated indicator from predictors which are received on the basis of data of remote sensing of a surface of the Earth. Canonical axes received as a result of the mixed correspondence analysis have been used as regression predictors. Continual data (digital elevation model and its derivative, vegetative and other Landsat indexes, relief and vegetative cover diversity indexes and discrete data (results of Earth surface classification on elementary relief units and types of a vegetative cover have been calculated by mixed correspondence analysis. The important result is dependence of electric conductivity of soil on indicators of a relief and a vegetative cover diversity.

  19. Spatial genetic structure in natural populations of Phragmites australis in a mosaic of saline habitats in the Yellow River Delta, China.

    Directory of Open Access Journals (Sweden)

    Lexuan Gao

    Full Text Available Determination of spatial genetic structure (SGS in natural populations is important for both theoretical aspects of evolutionary genetics and their application in species conservation and ecological restoration. In this study, we examined genetic diversity within and among the natural populations of a cosmopolitan grass Phragmites australis (common reed in the Yellow River Delta (YRD, China, where a mosaic of habitat patches varying in soil salinity was detected. We demonstrated that, despite their close geographic proximity, the common reed populations in the YRD significantly diverged at six microsatellite loci, exhibiting a strong association of genetic variation with habitat heterogeneity. Genetic distances among populations were best explained as a function of environmental difference, rather than geographical distance. Although the level of genetic divergence among populations was relatively low (F'(ST =0.073, weak but significant genetic differentiation, as well as the concordance between ecological and genetic landscapes, suggests spatial structuring of genotypes in relation to patchy habitats. These findings not only provided insights into the population dynamics of common reed in changing environments, but also demonstrated the feasibility of using habitat patches in a mosaic landscape as test systems to identify appropriate genetic sources for ecological restoration.

  20. On the bibliography of a late eighteenth-century German work on natural history and an early record of Leuciscus meidingeri Heckel, 1852 (Pisces, Cyprinidae) in the river system of the Upper Danube on 6th APRIL 1786

    NARCIS (Netherlands)

    Groot, de S.J.

    1972-01-01

    The bibliography of a hitherto inaccurately described anonymous eighteenth-century popular German work on natural history is given, dealing with mammals, birds, fishes, amphibians and reptiles. As an addendum to this work the publisher has given an engraving of an unknown fish from the river Lech,

  1. Estimating peak-flow frequency statistics for selected gaged and ungaged sites in naturally flowing streams and rivers in Idaho

    Science.gov (United States)

    Wood, Molly S.; Fosness, Ryan L.; Skinner, Kenneth D.; Veilleux, Andrea G.

    2016-06-27

    -central Idaho (average standard error of prediction=46.4 percent; pseudo-R2>92 percent) and region 5 in central Idaho (average standard error of prediction=30.3 percent; pseudo-R2>95 percent). Regression model fit was poor for region 7 in southern Idaho (average standard error of prediction=103 percent; pseudo-R2natural peak-flow conditions.The updated, regional peak-flow regression equations will be integrated in the U.S. Geological Survey StreamStats program to allow users to estimate basin and climatic characteristics and peak-flow statistics at ungaged locations of interest. StreamStats estimates peak-flow statistics with quantifiable certainty only when used at sites with basin and climatic characteristics within the range of input variables used to develop the regional regression equations. Both the regional regression equations and StreamStats should be used to estimate peak-flow statistics only in naturally flowing, relatively unregulated streams without substantial local influences to flow, such as large seeps, springs, or other groundwater-surface water interactions that are not widespread or characteristic of the respective region.

  2. Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

    Energy Technology Data Exchange (ETDEWEB)

    Jorgetto, A.O.; Silva, R.I.V.; Saeki, M.J.; Barbosa, R.C. [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil); Martines, M.A.U. [UFMS – Dept. Química, 79074-460 Campo Grande, MS (Brazil); Jorge, S.M.A.; Silva, A.C.P. [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil); Schneider, J.F. [USP – Instituto de Física de São Carlos, 13566-590 São Carlos, SP (Brazil); Castro, G.R., E-mail: castrogr@ibb.unesp.br [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil)

    2014-01-01

    Through a series of simple processes, cassava root husks were turned into a fine powder of controlled particle size (63–75 μm). FTIR spectrum demonstrated the existence of alcohol, amine and carboxylic groups; and elemental analysis confirmed the presence of elements of interest such as sulphur, nitrogen and oxygen. Cross-polarized {"1H}-{sup 13}C NMR technique indicated the existence of methionine and thiamine through the signals observed at 55 ppm and 54 ppm, respectively, and the point of zero charge (pH{sub pzc}) was achieved at pH 5.2. The material was applied in solid-phase extraction of Cu(II) via batch experiments. Optimum adsorption pH was found to be in range of 3–6 and in the kinetic experiment the equilibrium was attained in 1 min. The highest adsorption capacity was 0.14 mmol g{sup −1}. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, N{sub s}, was determined to be ∼0.14 mmol g{sup −1}, which is an indicative that the main adsorption mechanism is through chemisorption. Under optimized conditions, the material was utilized in preconcentration experiments, which culminated in an enrichment factor of 41.3-fold. With the aid of the enrichment factor, experiments were carried out to determine the Cu(II) content in tap water and natural water. Preconcentration method was also applied to a certified reference material (1643e) and the concentration found was 23.03 ± 0.79 μg L{sup −1}, whereas the specified Cu(II) concentration was 22.7 ± 0.31 μg L{sup −1}.

  3. Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water

    KAUST Repository

    Huang, Guocheng

    2011-04-15

    In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy and liquid chromatography with online organic carbon detector (LC-OCD) were used to investigate the fate of NOM fractions in the BAF+UF process. Results showed that the BAF process could effectively remove particles and parts of dissolved organic matter, which led to a lower NOM loading in the UF system, but different NOM fractions showed different biodegradation potentials. Further biodegradation batch experiments confirmed this observation and identified that polysaccharides and proteins (quantified using photometric methods) contained a large proportion of readily biodegradable matter while humic substances were mainly composed of inert organic substances. According to EEM measurements, it is evident that protein-like substances were more readily eliminated by microorganisms than humic-like substances. LC-OCD data also supported the phenomena that the polysaccharides and large-size proteins were more degradable than humic substances. © 2011 Springer-Verlag.

  4. Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water.

    Science.gov (United States)

    Huang, Guocheng; Meng, Fangang; Zheng, Xing; Wang, Yuan; Wang, Zhigang; Liu, Huijun; Jekel, Martin

    2011-06-01

    In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy and liquid chromatography with online organic carbon detector (LC-OCD) were used to investigate the fate of NOM fractions in the BAF + UF process. Results showed that the BAF process could effectively remove particles and parts of dissolved organic matter, which led to a lower NOM loading in the UF system, but different NOM fractions showed different biodegradation potentials. Further biodegradation batch experiments confirmed this observation and identified that polysaccharides and proteins (quantified using photometric methods) contained a large proportion of readily biodegradable matter while humic substances were mainly composed of inert organic substances. According to EEM measurements, it is evident that protein-like substances were more readily eliminated by microorganisms than humic-like substances. LC-OCD data also supported the phenomena that the polysaccharides and large-size proteins were more degradable than humic substances.

  5. A Multi-Scale Approach to Investigating the Red-Crowned Crane-Habitat Relationship in the Yellow River Delta Nature Reserve, China: Implications for Conservation.

    Science.gov (United States)

    Cao, Mingchang; Xu, Haigen; Le, Zhifang; Zhu, Mingchang; Cao, Yun

    2015-01-01

    The red-crowned crane (Grus japonensis (Statius Müller, 1776)) is a rare and endangered species that lives in wetlands. In this study, we used variance partitioning and hierarchical partitioning methods to explore the red-crowned crane-habitat relationship at multiple scales in the Yellow River Delta Nature Reserve (YRDNR). In addition, we used habitat modeling to identify the cranes' habitat distribution pattern and protection gaps in the YRDNR. The variance partitioning results showed that habitat variables accounted for a substantially larger total and pure variation in crane occupancy than the variation accounted for by spatial variables at the first level. Landscape factors had the largest total (45.13%) and independent effects (17.42%) at the second level. The hierarchical partitioning results showed that the percentage of seepweed tidal flats were the main limiting factor at the landscape scale. Vegetation coverage contributed the greatest independent explanatory power at the plot scale, and patch area was the predominant factor at the patch scale. Our habitat modeling results showed that crane suitable habitat covered more than 26% of the reserve area and that there remained a large protection gap with an area of 20,455 ha, which accounted for 69.51% of the total suitable habitat of cranes. Our study indicates that landscape and plot factors make a relatively large contribution to crane occupancy and that the focus of conservation effects should be directed toward landscape- and plot-level factors by enhancing the protection of seepweed tidal flats, tamarisk-seepweed tidal flats, reed marshes and other natural wetlands. We propose that efforts should be made to strengthen wetland restoration, adjust functional zoning maps, and improve the management of human disturbance in the YRDNR.

  6. Simulation of the spatial stresses due to territorial land development on Yellow River Delta Nature Reserve using a GIS-based assessment model.

    Science.gov (United States)

    Zhang, Baolei; Zhang, Qiaoyun; Feng, Qingyu; Cui, Bohao; Zhang, Shumin

    2017-07-01

    This study aimed at assessing the stresses from land development in or around Yellow River Delta Nature Reserve (YRDNR) and identifying the impacted areas. Major land development types (reservoirs, pond, aquafarm, salt pan, road, residential land, industry land, farming land, and fishing land) in or around the YRDNR from 1995 to 2014 were identified using spatial data sets derived from remote sensing imageries. The spatial stresses were simulated by considering disturbance due to land development activities and accessibility of disturbance using a geographic information system based model. The stresses were then used to identify the impacted area by land development (IALD). The results indicated that main increasing land development types in the study area from 1995 to 2014 were salt pan and construction land. The 98.2% of expanded land development area and 93.7% of increased pump number showed a good control of reserve function zone on land development spread. The spatial stress values and percentages of IALD increased from 1995 to 2014, and IALD percentage exceeded 50% for both parts of YRDNR in 2014. The results of this study also provided the information that detailed planning of the YRDNR (2014-2020) could decrease the spatial stress and IALD percentage of the whole YRDNR on the condition that the area of land development activities increased by 24.4 km 2 from 2014 to 2020. Effective measures should be taken to protect such areas from being further disturbed in order to achieve the goal of a more effective conservation of the YRDNR, and attention should be paid to the disordered land development activities in or around the natural reserves.

  7. Natural versus anthropogenic sources in the surface- and groundwater dissolved load of the Dommel river (Meuse basin): Constraints by boron and strontium isotopes and gadolinium anomaly

    Science.gov (United States)

    Petelet-Giraud, Emmanuelle; Klaver, Gerard; Negrel, Philippe

    2009-05-01

    SummaryThe river Dommel, a tributary of the Meuse River, drains an area of intensive agriculture (livestock farming, maize and grassland over 50% of the basin), and a dense population of about 600,000 people representing 20% of the total area. The combined human activities in the Dommel catchment lead to a large amount of dissolved elements and compounds released in surface- and groundwaters. The aim of this study was to discriminate the natural (including infiltration of Meuse water) versus anthropogenic sources of the dissolved load, and to identify the various pollution sources such as agriculture, industrial activity, and wastewater treatment plants, using geochemical tools including major- and trace elements, Sr and B isotopes, and rare earth elements (REE). For that purpose, a same-day geochemical "Snapshot" picture of the entire basin was combined with monthly monitoring in strategic points. The major- and trace elements analyses allowed discriminating the main pollution sources affecting the basin, i.e. point versus diffuse sources. Strontium isotopes helped to identify each tributary and to calculate mixing proportions. Combining these calculations with the Sr-isotopic data obtained from the "Snapshot" sampling campaign during a low-flow period, shows that Meuse water infiltration represents 25% of the total Dommel discharge. Boron isotopes used for assessing the amount of water affected by anthropogenic input cannot discriminate between the two main anthropogenic inputs, i.e. urban wastewater and the zinc-smelter effluent, as they have similar δ11B values. Finally, the REE, and especially the use of Gd anomalies (Gd ∗), demonstrated the generalized impact of urban wastewater on the streams of the Dommel Basin. The coupled use of different geochemical tracers (Sr and B isotopes together with Gd ∗) in addition to the standard major-element analyses, led to discriminating the various anthropogenic components influencing the Dommel Basin water quality

  8. Mass-selective Detection of Persistent Organic Pollutants by GC/MS Isolation, Concentration, Identification and Determination of Isomeric Spesific Composition of PCB in Natural and Drinking Waters of Dnieper River Basin in Kiev Region

    OpenAIRE

    Milyukin, Mikhail V.

    2002-01-01

    In concentrates of natural and drinking waters of Dnieper river basin in Kiev region with enrichment factor of 2,0⋅105–4,0⋅105 PCB (PCB524, PCB664, PCB1015, PCB1185, PCB1055, PCB1536, PCB1386, PCB1807, PCB2008) have been identified and their isomeric-specific composition (tetrachloro- – heptachloroisomers) has been determined at MDL level as low as 10–400 pg/L

  9. Skjern River Restoration Counterfactual

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    of Dissonance in Nature Restoration’, Journal of Landscape Architecture 2/2014: 58-67. Danish Nature Agency (2005), Skjern Å: Ådalens historie. De store projekter. Det nye landskab og naturen. På tur i ådalen [The Skjern River: The History of the River Delta. The Big Projects. The New Landscape and Nature......In 2003 the Skjern River Restoration Project in Denmark was awarded the prestigious Europa Nostra Prize for ‘conserving the European cultural heritage’ (Danish Nature Agency 2005). In this case, however, it seems that the conservation of one cultural heritage came at the expense of another cultural...... history and more openness towards constant change. In this approach the idea of palimpsest as metaphor for the cultural landscape plays an important role. Rather than being an obstacle for the restoration of nature, the historical layer following the comprehensive cultivation project from the 1960s...

  10. The source of natural and anthropogenic heavy metals in the sediments of the Minjiang River Estuary (SE China): implications for historical pollution.

    Science.gov (United States)

    Xu, Yonghang; Sun, Qinqin; Yi, Liang; Yin, Xijie; Wang, Aijun; Li, Yunhai; Chen, Jian

    2014-09-15

    Two sedimentary cores in the Minjiang River estuary (SE China) are documented for grain size, clay minerals, heavy metals, magnetic parameters and Pb isotopes to investigate the source and historical variation of heavy metals. The MJK9 core was collected outside of the Minjiang River estuary, and the core is composed of mixed sediments, of which ~70% from the Yangtze River and 30% from the Minjiang River. It is thus difficult to be used for tracing the human activity along the Minjiang River. In contrast, the sediments of MJK16 core which was collected in a nearshore area are primarily from the Minjiang River. The enrichment factors of the sediments were pollution. The results indicate that the sediments of the MJK16 core have Cu and Pb concentrations increasing since 1980, associated with the increase of magnetic mineral concentration and (206)Pb/(207)Pb and (206)Pb/(208)Pb of the sediments. We compared the Pb isotopic compositions between our results and those for the deposit mining in the Minjiang River basin, and aerosols and coal dust in south China, and considered that Pb in the sediments of the MJK16 core was derived primarily from weathered rocks as well as industrial emission (e.g. coal combustion). The sediments have anthropogenic Pb concentrations ranging from 6% in 1950 to 23.7% in 2010, consistent with the impact of rapid urban and industrial development in China. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Missouri River, Natural Resources Bibliography.

    Science.gov (United States)

    1997-07-01

    Fish Dept., Proj. No. W- report 4. 067-R-12. 120 p. 456. EMERSON DG, WALD JD. 1983. Inventory and 464. ERDEI JF. 1963. Control of taste and odor in...369- the American Philosophical Society 12:1-218. 75. 690. HAYDEN FV. 1866. On the extensive chalk 680. HATCHER MP, NEEL JK, ERDEI JF, HARTUNG deposit...1453 Dashputre, M.S. 161 Dowling, J.D. 4 Erdei , J.F. 464, 680 Davey, J.C. 381 Drain, M.A. 415 Erdmann, A.L. 290 Davidson, M. 736 Drake, E.T. 1430

  12. Contamination assessment of arsenic and heavy metals in a typical abandoned estuary wetland--a case study of the Yellow River Delta Natural Reserve.

    Science.gov (United States)

    Xie, Zhenglei; Sun, Zhigao; Zhang, Hua; Zhai, Jun

    2014-11-01

    Coastal and estuarine areas are often polluted by heavy metals that result from industrial production and agricultural activities. In this study, we investigated the concentration trait and vertical pattern of trace elements, such as As, Cd, Ni, Zn, Pb, Cu, and Cr, and the relationship between those trace elements and the soil properties in coastal wetlands using 28 profiles that were surveyed across the Diaokouhe Nature Reserve (DKHNR). The goal of this study is to investigate profile distribution characteristics of heavy metals in different wetland types and their variations with the soil depth to assess heavy metal pollution using pollution indices and to identify the pollution sources using multivariate analysis and sediment quality guidelines. Principal component analysis, cluster analysis, and pollution level indices were applied to evaluate the contamination conditions due to wetland degradation. The findings indicated that the concentration of trace elements decreased with the soil depth, while Cd increases with soil depth. The As concentrations in reed swamps and Suaeda heteroptera surface layers were slightly higher than those in other land use types. All six heavy metals, i.e., Ni, Cu, As, Zn, Cr, and Pb, were strongly associated with PC1 (positive loading) and could reflect the contribution of natural geological sources of metals into the coastal sediments. PC2 is highly associated with Cd and could represent anthropogenic sources of metal pollution. Most of the heavy metals exhibited significant positive correlations with total concentrations; however, no significant correlations were observed between them and the soil salt and soil organic carbon. Soil organic carbon exhibited a positive linear relationship with Cu, Pb, and Zn in the first soil layer (0-20 cm); As, Cr, Cu, Ni, Pb, and Zn in the second layer (20-40 cm); and As, Cr, Cu, Ni, Pb, and Zn in the third layer (40-60 cm). Soil organic carbon exhibited only a negative correlation with Cd (P

  13. Hydroquinone-Mediated Redox Cycling of Iron and Concomitant Oxidation of Hydroquinone in Oxic Waters under Acidic Conditions: Comparison with Iron-Natural Organic Matter Interactions.

    Science.gov (United States)

    Jiang, Chao; Garg, Shikha; Waite, T David

    2015-12-15

    Interactions of 1,4-hydroquinone with soluble iron species over a pH range of 3-5 in the air-saturated and partially deoxygenated solution are examined here. Our results show that 1,4-hydroquinone reduces Fe(III) in acidic conditions, generating semiquinone radicals (Q(•-)) that can oxidize Fe(II) back to Fe(III). The oxidation rate of Fe(II) by Q(•-)increases with increase in pH due to the speciation change of Q(•-) with its deprotonated form (Q(•-)) oxidizing Fe(II) more rapidly than the protonated form (HQ(•)). Although the oxygenation of Fe(II) is negligible at pH iron redox transformation by rapidly oxidizing Q(•-) to form benzoquinone (Q). A kinetic model is developed to describe the transformation of quinone and iron under all experimental conditions. The results obtained here are compared with those obtained in our previous studies of iron-Suwannee River fulvic acid (SRFA) interactions in acidic solutions and support the hypothesis that hydroquinone moieties can reduce Fe(III) in natural waters. However, the semiquinone radicals generated in pure hydroquinone solution are rapidly oxidized by dioxygen, while the semiquinone radicals generated in SRFA solution are resistant to oxidation by dioxygen, with the result that steady-state semiquinone concentrations in SRFA solutions are 2-3 orders of magnitude greater than in solutions of 1,4-hydroquinone. As a result, semiquinone moieties in SRFA play a much more important role in iron redox transformations than is the case in solutions of simple quinones such as 1,4-hydroquinone. This difference in the steady-state concentration of semiquinone species has a dramatic effect on the cycling of iron between the +II and +III oxidation states, with iron turnover frequencies in solutions containing SRFA being 10-20 times higher than those observed in solutions of 1,4-hydroquinone.

  14. Dissonant Nature

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2013-01-01

    Nature restoration is far from being a neural undertaking. Just like any other type of heritage production it can be the source of dissonance – ‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particular sensitive to site-specificity. As exempl...... and allows for multiple interpretations to coexist. Evidence can be found in the Re-naturalization of River Aire (2002-2015), a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  15. River classification is important for reporting ecological status and ...

    African Journals Online (AJOL)

    River classification is important for reporting ecological status and for the general ecological management of river systems by partitioning natural variability. A priori river classification by abiotic variables and validation of classifications obtained.

  16. THE RESULTS OF THE MONITORING OF NATURAL AND TECHNOGENIC POLLUTION OF THE RIVERS OF GORNY ALTAI WITH THE HELP OF SATELLITE IMAGES LANDSAT 8

    Directory of Open Access Journals (Sweden)

    A. V. Shitov

    2015-01-01

    Full Text Available 2014 we were monitored pollution incidents in tributaries of the river Lebed in Turochaksky rayon of the Altai Republic. It was also made the identification of sources of pollution through satellite imagery and GIS technologies.

  17. Hydrophysical conditions and periphyton in natural rivers. Analysis and predictive modelling of periphyton by changed regulations; Hydrofysiske forhold og begroing i naturlige elver. Analyse og prediktiv modellering av begroing ved reguleringsendringer

    Energy Technology Data Exchange (ETDEWEB)

    Stokseth, S.

    1994-10-01

    The objective of this thesis has been to examine the interaction between hydrodynamical and physical factors and the temporal and spatial dynamics of periphyton in natural steep rivers. The study strategy has been to work with quantitative system variables to be able to evaluate the potential usability of a predictive model for periphyton changes as a response to river regulations. The thesis is constituted by a theoretical and an empirical study. The theoretical study is aimed at presenting a conceptual model of the relevant factors based on an analysis of published studies. Effort has been made to evaluate and present the background material in a structured way. To concurrently handle the spatial and temporal dynamics of periphyton a new method for data collection has been developed. A procedure for quantifying the photo registrations has been developed. The simple hydrodynamical parameters were estimated from a set of standard formulas whereas the complex parameters were estimated from a three dimensional simulation model called SSIIM. The main conclusion from the analysis is that flood events are the major controlling factors wrt. periphyton biomass and that water temperature is of major importance for the periphyton resistance. Low temperature clearly increases the periphyton erosion resistance. Thus, to model or control the temporal dynamics the river periphyton, the water temperature and the frequency and size of floods should be regarded the most significant controlling factors. The data in this study has been collected from a river with a stable water quality and frequent floods. 109 refs., 41 figs., 34 tabs.

  18. Minnesota Wild and Scenic River Districts

    Data.gov (United States)

    Minnesota Department of Natural Resources — District boundaries for wild, scenic, and recreational rivers designated under the Minnesota State Wild and Scenic Rivers Act. Includes portions of the Minnesota...

  19. Human-induced river runoff overlapping natural climate variability over the last 150 years: Palynological evidence (Bay of Brest, NW France)

    Science.gov (United States)

    Lambert, Clément; Penaud, Aurélie; Vidal, Muriel; Klouch, Khadidja; Gregoire, Gwendoline; Ehrhold, Axel; Eynaud, Frédérique; Schmidt, Sabine; Ragueneau, Olivier; Siano, Raffaele

    2018-01-01

    For the first time a very high resolution palynological study (mean resolution of 1 to 5 years) was carried out over the last 150 years in a French estuarine environment (Bay of Brest; NW France), allowing direct comparison between the evolution of landscapes, surface water, and human practices on Bay of Brest watersheds, through continental (especially pollen grains) and marine (phytoplanktonic microalgae: cysts of dinoflagellates or dinocysts) microfossils. Thanks to the small size of the watersheds and the close proximity of the depositional environment to the mainland, the Bay of Brest represents an ideal case study for palynological investigations. Palynological data were then compared to published palaeo-genetic analyses conducted on the same core and to various available instrumental data, allowing us to better characterize past environmental variability since the second half of the 19th century in Western Brittany. We provide evidence of some clues of recent eutrophication and/or pollution that affected phytoplankton communities and which appears linked with increased runoff (higher precipitations, higher percentages of riparian forest pollen, decline of salt marsh-type indicators, and higher values of the XRF Ti/Ca signal), mainly explained by the evolution of agricultural practices since 1945 superimposed on the warming climate trend. We assume that the significant relay observed between dinocyst taxa: Lingulodinium machaerophorum and Spiniferites bentorii around 1965 then followed by Spiniferites membranaceus after 1985, attests to a strong and recent eutrophication of Bay of Brest surface waters induced by high river runoff combined with abnormally elevated air temperatures, especially obvious in the data from 1990. The structure of the dinocyst community has thus been deeply altered, accompanied by an unprecedented increase of Alexandrium minutum toxic form at the same period, as confirmed by the genetic quantification. Despite this recent major

  20. A comparison of the wild food plant use knowledge of ethnic minorities in Naban River Watershed National Nature Reserve, Yunnan, SW China

    Directory of Open Access Journals (Sweden)

    Ghorbani Abdolbaset

    2012-05-01

    Full Text Available Abstract Background Wild food plants (WFPs contribute to the nutrition, economy and even cultural identity of people in many parts of the world. Different factors determine the preference and use of WFPs such as abundance, availability, cultural preference, economic conditions, shortage periods or unsecure food production systems. Understanding these factors and knowing the patterns of selection, use and cultural significance and value of wild food plants for local communities is helpful in setting priorities for conservation and/or domestication of these plants. Thus in this study knowledge of wild food plant use among four groups namely Dai, Lahu, Hani and Mountain Han in Naban River Watershed National Nature Reserve ((NRWNNR, Xishuangbanna were documented and analyzed to find the similarity and difference among their plant use. Methods Data on wild food plant use was collected through freelisting and semi-structured interviews and participatory field collection and direct observation. Botanical plant sample specimens were collected, prepared, dried and identified. Results A total of 173 species and subspecies from 64 families and one species of lichen (Ramalina sp. are used as WFP. There were differences on the saliency of wild food plant species among four ethnic groups. Consensus analysis revealed that knowledge of wild food plant use for each ethnic group differs from others with some variation in each group. Among informant attributes only age was related with the knowledge of wild food plant use, whereas no significant relationship was found between gender and age*gender and informants knowledge of wild food plant use. Conclusion Wild food plants are still used extensively by local people in the NRWNNR, some of them on a daily base. This diversity of wild food plants provide important source of nutrients for the local communities which much of their caloric intake comes from one or few crops. The results also show the role of ethnicity

  1. Combining U speciation and U isotope fractionation to evaluate the importance of naturally reduced sediments in controlling the mobility of uranium in the upper Colorado River Basin

    Science.gov (United States)

    Noel, V.; Lefebvre, P.; Boye, K.; Bargar, J.; Maher, K.; Lezama-Pacheco, J.; Cardarelli, E.; Bone, S.; Dam, W. L.; Johnson, R. H.

    2015-12-01

    Long-term persistence of uranium (U) in groundwater at legacy ore-processing sites in the upper Colorado River Basin (CRB) is a major concern for DOE, stakeholders, and local property owners. In the past year, we have investigated U distributions in contaminated floodplains at Grand Junction, Naturita, and Rifle (CO), Riverton (WY), and Shiprock (NM). We find that U is retained at all locations in fine-grained, organic-rich sulfidic sediments, referred to as naturally reduced zones (NRZs). The retention mechanisms (e.g., complexation, precipitation or adsorption) and the processes responsible for U accumulation in NRZs will directly determine the capacity of the sediments to prevent U mobilization. However, these processes remain poorly understood at local and regional scales yet they are critical to management and remediation of these sites. We have used U LIII/II-edge XANES to systematically characterize U oxidation states, and EXAFS and bicarbonate extractions to characterize U local structure and reactivity in order to distinguish the forms of U. We are measuring U isotopic signatures (δ238/235U) to better understand uranium sources and processes of accumulation in NRZs. We have found that high U concentrations correspond to reduced and relatively insoluble U forms, mainly non-crystalline U(IV), and co-occur with ferrous iron and sulfides. This suggests that reduction processes, fueled by the high organic matter content and constrained to the diffusion-limited environment in the fine-grained NRZs, are important for the retention of U in these sediments. We also observe a strong correlation between the U concentrations in the NRZs and the extent of isotopic fractionation, with up to +1.8 ‰ difference between uranium-enriched and low concentration zones. In some locations the δ238/235U values are within the range of values typical of the mine tailings, whereas at other sites the more positive δ238/235U values suggest that redox cycling and/or partial

  2. A comparison of the wild food plant use knowledge of ethnic minorities in Naban River Watershed National Nature Reserve, Yunnan, SW China.

    Science.gov (United States)

    Ghorbani, Abdolbaset; Langenberger, Gerhard; Sauerborn, Joachim

    2012-05-05

    Wild food plants (WFPs) contribute to the nutrition, economy and even cultural identity of people in many parts of the world. Different factors determine the preference and use of WFPs such as abundance, availability, cultural preference, economic conditions, shortage periods or unsecure food production systems. Understanding these factors and knowing the patterns of selection, use and cultural significance and value of wild food plants for local communities is helpful in setting priorities for conservation and/or domestication of these plants. Thus in this study knowledge of wild food plant use among four groups namely Dai, Lahu, Hani and Mountain Han in Naban River Watershed National Nature Reserve ((NRWNNR), Xishuangbanna were documented and analyzed to find the similarity and difference among their plant use. Data on wild food plant use was collected through freelisting and semi-structured interviews and participatory field collection and direct observation. Botanical plant sample specimens were collected, prepared, dried and identified. A total of 173 species and subspecies from 64 families and one species of lichen (Ramalina sp.) are used as WFP. There were differences on the saliency of wild food plant species among four ethnic groups. Consensus analysis revealed that knowledge of wild food plant use for each ethnic group differs from others with some variation in each group. Among informant attributes only age was related with the knowledge of wild food plant use, whereas no significant relationship was found between gender and age*gender and informants knowledge of wild food plant use. Wild food plants are still used extensively by local people in the NRWNNR, some of them on a daily base. This diversity of wild food plants provide important source of nutrients for the local communities which much of their caloric intake comes from one or few crops. The results also show the role of ethnicity on the preference and use of wild food plants. There is a big

  3. Different Approaches to investigate the interfacial interactions between Natural Organic Matter and Metal Oxide

    KAUST Repository

    Zaouri, Noor A.

    2017-12-01

    A variety of approaches were conducted to obtain a comprehensive understanding of the adsorption of Natural Organic Matter (NOM) isolates on metal oxides (MeO). Adsorption experiments with a series of small molecular weight (MW), oxygenated, aromatic organic acids were performed with Aluminum oxide (Al2O3), Titanium oxide (TiO2), and Zirconium oxide (ZrO2) surface. The experiments were conducted in batch mode at pH 4.2 and 7.6. The adsorption of simple organic acids was described by Langmuir model, and exhibited strong dependence on the relative abundance of carboxyl group, aliphaticity/aromaticity, length of alkyl chain, and the presence of hydroxyl group. The adsorption of the model compounds was high at low pH and decreased with increasing the pH. Isolated NOM fraction of strong humic character, i.e., hydrophobic (HPO) (high in MW, aromaticity, and acidity), i.e., Suwannee River fulvic acid (SRW HPO), showed strong adsorption on all MeO. However, fractions with similar acidic character, and lower MW exerted weak adsorption. NOM fraction that incorporated polysaccharides and proteins like structures (i.e., biopolymers) was not significantly adsorbed compared to HPO fractions. Interestingly, biopolymer adsorption on Heated Aluminum oxide particles (HAOP) was higher than that on Al2O3, TiO2, and ZrO2. These different adsorption profiles were related to their physicochemical characteristics of NOM and MeO, and thus, showed different interacting mechanisms and were studied by Atomic Force Microscopy (AFM). Hydrogen bonding was suggested as the main mechanism between NOM of strong hydrophilic character (i.e., biopolymers) and Al2O3, TiO2 and ZrO2 coated wafers. The strength of the hydrogen bonding was influenced by the hydrophilicity degree of MeO surface, ionic strength, and cation type. NOM fractions with strong humic character showed repulsive forces that are electrostatic in nature with MeO of high negative charge density. Hydrogen bonding and ligand exchange

  4. Investigations into the Early Life-history of Naturally Produced Spring Chinook Salmon and Summer Steelhead in the Grande Ronde River Basin, Annual Report 2001.

    Energy Technology Data Exchange (ETDEWEB)

    Reischauer, Alyssa; Monzyk, Frederick; Van Dyke, Erick

    2003-06-01

    We determined migration timing and abundance of juvenile spring chinook salmon Oncorhynchus tshawytscha and juvenile steelhead/rainbow trout Oncorhynchus mykiss using rotary screw traps on four streams in the Grande Ronde River basin during the 2001 migratory year (MY 2001) from 1 July 2000 through 30 June 2001. Based on migration timing and abundance, two distinct life-history strategies of juvenile spring chinook and O. mykiss could be distinguished. An 'early' migrant group left upper rearing areas from 1 July 2000 through 29 January 2001 with a peak in the fall. A 'late' migrant group descended from upper rearing areas from 30 January 2001 through 30 June 2001 with a peak in the spring. The migrant population of juvenile spring chinook salmon in the upper Grande Ronde River in MY 2001 was very low in comparison to previous migratory years. We estimated 51 juvenile spring chinook migrated out of upper rearing areas with approximately 12% of the migrant population leaving as early migrants to overwinter downstream. In the same migratory year, we estimated 16,067 O. mykiss migrants left upper rearing areas with approximately 4% of these fish descending the upper Grande Ronde River as early migrants. At the Catherine Creek trap, we estimated 21,937 juvenile spring chinook migrants in MY 2001. Of these migrants, 87% left upper rearing areas early to overwinter downstream. We also estimated 20,586 O. mykiss migrants in Catherine Creek with 44% leaving upper rearing areas early to overwinter downstream. At the Lostine River trap, we estimated 13,610 juvenile spring chinook migrated out of upper rearing areas with approximately 77% migrating early. We estimated 16,690 O. mykiss migrated out of the Lostine River with approximately 46% descending the river as early migrants. At the Minam River trap, we estimated 28,209 juvenile spring chinook migrated out of the river with 36% migrating early. During the same period, we estimated 28,113 O. mykiss with

  5. Effect of spatial heterogeneity of runoff generation mechanisms on the scaling behavior of event runoff responses in a natural river basin

    NARCIS (Netherlands)

    Li, H.; Sivapalan, M.

    2011-01-01

    This paper presents a theoretical investigation of the effects of spatial heterogeneity of runoff generation on the scaling behavior of runoff timing responses. A previous modeling study on the Illinois River Basin in Oklahoma had revealed a systematic spatial trend in the relative dominance of

  6. 87Sr/86Sr and 143Nd/144Nd for disentangling anthropogenic and natural REE contributions in river water during flood events.

    Science.gov (United States)

    Hissler, Christophe; Stille, Peter; Pfister, Laurent

    2017-04-01

    The sustainable management of water resources is one of the greatest challenges of the 21st century. Water is a vital resource that is increasingly put under pressure from multiple perspectives. While the global population is on the rise, socio-economic development makes equally rapid progress - eventually compromising access to clean water bodies. Multiple pollution sources constitute an immediate threat to aquatic ecosystems and are likely to cause long lasting contaminations of water bodies that are critical for drinking and/or irrigation water production. There is a pressing need for an adequate quantification of anthropogenic impacts on the critical zone of river basins and the identification of the temporal dynamics of these impacts. As an example, despite the work done to assess the environmental impact of REE pollutions in larger river systems, we are still lacking information on the dynamics of these anthropogenic compounds in relation to rapid hydrological changes. Filling these knowledge gaps is a pre-requisite for the design and implementation of sustainable water resources management strategies. In order to better constrain the relative contributions of both anthropogenic and geogenic trace element sources we propose using a multitracer approach combining elemental and 87Sr/86Sr, 143Nd/144Nd, and 206Pb/207Pb isotopic ratios. The use of these three separate isotopic systems together with REE concentrations is new in the field of anthropogenic source identification in river systems. We observed enrichments in Anthropogenic Rare Earth Elements (AREE) for dissolved Gd and suspended Nd loads of river water. With increasing discharge, AREE anomalies progressively disappeared and gave way to the geogenic chemical signature of the basin in both dissolved and suspended loads. The isotopic data confirm these observations and shed new light on the trace elements sources. On the one hand, dissolved loads have peculiar isotopic characteristics and carry mainly

  7. Effects of water temperature and discharge on natural reproduction time of the Chinese sturgeon, Acipenser sinensis, in the Yangtze River, China and impacts of the impoundment of the Three Gorges Reservoir.

    Science.gov (United States)

    Gao, Xin; Lin, Pengcheng; Li, Mingzheng; Duan, Zhonghua; Liu, Huanzhang

    2014-05-01

    Chinese sturgeon, Acipenser sinensis, is a critically endangered anadromous fish species spawning in the Yangtze River of China during October and November. In this study, we analyzed the effects of hydrological factors, such as water temperature and discharge, on the natural reproduction time of the Chinese sturgeon and evaluated the impact of the impoundment of the Three Gorges Reservoir (TGR) based on our survey data from 1998 to 2011. The results showed that the first spawning dates were significantly (P Three Gorges Dam (TGD), to enhance water discharge downstream in October, and to complete impoundment before October.

  8. Co-creating Understanding in Water Use & Agricultural Resilience in a Multi-scale Natural-human System: Sacramento River Valley--California's Water Heartland in Transition

    Science.gov (United States)

    Fairbanks, D. H.; Brimlowe, J.; Chaudry, A.; Gray, K.; Greene, T.; Guzley, R.; Hatfield, C.; Houk, E.; Le Page, C.

    2012-12-01

    The Sacramento River Valley (SRV), valued for its $2.5 billion agricultural production and its biodiversity, is the main supplier of California's water, servicing 25 million people. . Despite rapid changes to the region, little is known about the collective motivations and consequences of land and water use decisions, or the social and environmental vulnerability and resilience of the SRV. The overarching research goal is to examine whether the SRV can continue to supply clean water for California and accommodate agricultural production and biodiversity while coping with climate change and population growth. Without understanding these issues, the resources of the SRV face an uncertain future. The defining goal is to construct a framework that integrates cross-disciplinary and diverse stakeholder perspectives in order to develop a comprehensive understanding of how SRV stakeholders make land and water use decisions. Traditional approaches for modeling have failed to take into consideration multi-scale stakeholder input. Currently there is no effective method to facilitate producers and government agencies in developing a shared representation to address the issues that face the region. To address this gap, researchers and stakeholders are working together to collect and consolidate disconnected knowledge held by stakeholder groups (agencies, irrigation districts, and producers) into a holistic conceptual model of how stakeholders view and make decisions with land and water use under various management systems. Our approach integrates a top-down approach (agency stakeholders) for larger scale management decisions with a conceptual co-creation and data gathering bottom-up approach with local agricultural producer stakeholders for input water and landuse decisions. Land use change models that combine a top-down approach with a bottom-up stakeholder approach are rare and yet essential to understanding how the social process of land use change and ecosystem function are

  9. Influence of organic matter from urban effluents on trace metal speciation and bioavailability in river under strong urban pressure

    Directory of Open Access Journals (Sweden)

    Matar Z.

    2013-04-01

    Full Text Available In aquatic systems, dissolved organic matter (DOM constitutes a key component of the carbon cycle controlling the transport, speciation, bioavailability and toxicity of trace metals. In this work, we study the spatio-temporal variability of the MO in terms of both quality and quantity from upstream to downstream the Parisian conurbation. Urban discharges which are the main source of allochthonous organic matter into the Seine at low water periods were also investigated. The DOM collected was fractionated according to polarity criteria into five fractions: hydrophobic, transphilic, hydrophilic acid, hydrophilic basic and hydrophilic neutral. Due to urban discharges a strong enrichment in the hydrophilic (HPI fraction was observed for downstream sites. This hydrophilic fraction presented stronger binding capacities for copper than hydrophobic fraction from less urbanized site (upstream from Paris and than Suwannee river fulvic acid (SRFA. Furthermore, biotests highlighted a significant copper bioavailability decrease in presence of hydrophilic DOM.

  10. Longitudinal dispersion in natural channels: 2. The roles of shear flow dispersion and dead zones in the River Severn, U.K.

    Directory of Open Access Journals (Sweden)

    P. M. Davis

    2000-01-01

    Full Text Available The classical one-dimensional advection-diffusion equation (ADE gives an inadequate description of tracer cloud evolution in the River Severn, U.K. A solute transport model incorporating the effects of tracer storage in dead zones is presented in which the channel is conceived as being divided into two parallel regions. The bulk flow region occurs in the central part. Its longitudinal dispersive properties are described by the ADE. Adjacent to this, an additional cross-sectional area is defined in which tracer can be stored temporarily in regions of slowly moving water called dead zones. Exchange between the two regions follows a first order rate equation. Applying the model to the River Severn shows that a dispersing cloud’s evolution occurs in two distinct stages with a rapid transitional phase. Initially, shear-dispersion is dominant while the tracer particles mix fully over the bulk flow. Once this has occurred, dead zone storage accounts well for the non-Fickian evolution of the cloud. After the transitional phase the dead zone storage mechanism clearly dominates over shear-dispersion. Overall, the combined shear flow dispersion – dead zone model (D-DZM provides a much better, physically consistent description of the tracer cloud’s evolution than the simple classical ADE approach can do alone. Keywords: Channels; dispersion; dead zones; tracers; River Severn

  11. Connecticut River Hydrologic Observatory

    Science.gov (United States)

    Ballestero, T. P.

    2004-12-01

    The Connecticut River basin possesses some characteristics that make it unique for studying hydrologic issues that transcend scale. The watershed was first dramatically altered through natural processes (glaciation) and then heavily impacted by human stresses (dams, deforestation, acid precipitation/deposition), only to exhibit recent decades of return to a more natural state (reforestation, land conservation, stream restoration, pollution abatement, and dam removal). The watershed is sufficiently north to be classified as a cold region. More specifically to hydrology, the watershed exhibits the spectrum of flooding problems: ice dams, convective storms, hurricanes, rain on melting snow, and low pressure systems. The 28,000 square kilometer Connecticut River Watershed covers one third of the states of New Hampshire, Vermont, Massachusetts, and Connecticut. The >640-km long rivers' headwaters start on the Canadian border at the Fourth Connecticut Lake, and flows southward to discharge in Long Island sound. The lower 100 km of river are tidally influenced. The Connecticut River is responsible for 70 % of the freshwater inflow to Long Island Sound. The Connecticut River is a sixth order stream that exhibits a dendritic pattern in an elongated scheme. This setting therefore affords many first and second order streams in almost parallel fashion, flowing west or east towards the central Connecticut River spine. There are 38 major tributaries to the mainstem Connecticut River, and 26 of these tributaries drain greater than 250 square kilometers. There is in excess of 30,000 km of perennially flowing stream length in the watershed. For more information, see: http://www.unh.edu/erg/connho/

  12. Surface-enhanced Raman spectroscopy (SERS) to detect natural organic coatings on silver nanoparticles

    Science.gov (United States)

    Kühn, Melanie; Ivleva, Natalia P.; Klitzke, Sondra; von der Kammer, Frank; Niessner, Reinhard; Baumann, Thomas

    2015-04-01

    Applications for engineered inorganic nanoparticles (EINP) are rising and causing a higher risk for EINP to be released into the environment. Their stability and transport behaviour under environmental conditions is strongly depending on their surface properties which on the other hand depend on the presence or absence of a surface coating. We assume that EINP get coated soon after their release into the environment e.g. by humic substances like humic or fulvic acids and NOM. Often EINP are stabilized by a coating agent like citrate or polyvinylpyrrolidone. Therefore, the replacement of the initial coating material or a multilayer coating has to be considered. Characterization of natural coatings on EINP is crucial to predict their environmental behaviour, but analytical methods to investigate organic coatings are scarce. To investigate humic- and fulvic acid coatings on silver nanoparticles (Ag NP) Raman micro-spectroscopy (RM) was used. RM is limited in its sensitivity, but silver nanoparticles cause an enhancement of the Raman signal of adsorbed substances by a factor of 103-106, so called surface-enhanced Raman spectroscopy (SERS). The Raman spectrum of humic acids is dominated by the carbonaceous parts of the humic acids which are known from carbon analysis and referred to as defect (D) and graphite (G) peak of carbon. Humic acids of different origin (humic acid from a lignite, suwannee river humic acid) showed differences in the D and G ratios indicating a difference in the structure of the contained carbon. With SERS humic and fulvic acid coatings on Ag NP were analysed: 1-100 mg/L humic acid stock solution were mixed with citrate and hydroxylammoniumchloride stabilized Ag NP, centrifuged and resuspended in deionized water (washing) to remove all coating material not associated with Ag NP. This washing step was repeated up to four times. SERS prooved that the coating was still present after the fourth washing step. As SERS is only sensitive for substances in

  13. Natural gas sources, migration and accumulation in the shallow water area of the Panyu lower uplift: An insight into the deep water prospects of the Pearl River Mouth Basin, South China Sea

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.H.; Chen, C.M.; Pang, X.; Jiahao, W.H.; Shi, W.Z. [China University of Geoscience, Wuhan (China)

    2006-04-15

    Although no drilling has been carried out in the deep water area of the Baiyun sag in the Pearl River Mouth Basin, South China Sea, the successful exploration for natural gas in the shallow water area of the Panyu lower uplift allows an insight into the prospectivity of the adjacent deep water fan system of the Baiyun sag. The Paleogene gas kitchen in the Baiyun sag provided both oil-derived gas and coal-derived gas. Fluid inclusion measurements and 2D numeric modelling of formation pressure indicate four episodes of hydrocarbon charge since the third release of the overpressure system. Seismic wipeout zones manifest several types of gas chimney which could play a role in vertical migration conduits to feed the natural gases into the deep water fan system. There would be, therefore, a low risk for hydrocarbon exploration in the deep water fan system.

  14. Developing Rivers

    Directory of Open Access Journals (Sweden)

    Abhik Chakraborty

    2013-10-01

    Full Text Available This article explores the reasons behind the continuation of contentious dam projects in Japanese river basins. Though the River Law of the country was reformed in 1997, and subsequent sociopolitical developments raised hopes that river governance would progress toward a more environment-oriented and bottom-up model, basin governance in Japan remains primarily based on a utilitarian vision that sees rivers as waterways. This article reviews the Achilles heel of the 1997 River Law by examining some most contentious river valley projects, and concludes that a myth of vulnerability to flooding, short-sightedness of river engineers, and bureaucratic inertia combine to place basin governance in a time warp: as projects planned during postwar reconstruction and economic growth continue to be top priorities in policymaking circles while concerns over environment remain largely unaddressed.

  15. River-corridor habitat dynamics, Lower Missouri River

    Science.gov (United States)

    Jacobson, Robert B.

    2010-01-01

    Intensive management of the Missouri River for navigation, flood control, and power generation has resulted in substantial physical changes to the river corridor. Historically, the Missouri River was characterized by a shifting, multithread channel and abundant unvegetated sandbars. The shifting channel provided a wide variety of hydraulic environments and large areas of connected and unconnected off-channel water bodies.Beginning in the early 1800s and continuing to the present, the channel of the Lower Missouri River (downstream from Sioux City, Iowa) has been trained into a fast, deep, single-thread channel to stabilize banks and maintain commercial navigation. Wing dikes now concentrate the flow, and revetments and levees keep the channel in place and disconnect it from the flood plain. In addition, reservoir regulation of the Missouri River upstream of Yankton, South Dakota, has substantially changed the annual hydrograph, sediment loads, temperature regime, and nutrient budgets.While changes to the Missouri River have resulted in broad social and economic benefits, they have also been associated with loss of river-corridor habitats and diminished populations of native fish and wildlife species. Today, Missouri River stakeholders are seeking ways to restore some natural ecosystem benefits of the Lower Missouri River without compromising traditional economic uses of the river and flood plain.

  16. Pluralising Nature

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2017-01-01

    Denmark is recognised for its democratic approach to planning, and for the idea of planning for the common good. This interest in the common good and in common values also seems to be reflected in the way that the restoration of nature is planned and managed, suggesting that there is one common...... “nature” that everyone can agree on. But nature restoration is far from being an unproblematic undertaking. As with any other type of heritage production, it can be the source of dissonance. As exemplified by the Skjern River Restoration Project, one perception of a landscape and its value as “nature” can...... suppress other valid perceptions, in conflict with the need for different groups of people to be able to identify with the same territory. However, planning for the common good, in the case of nature restoration, does not necessarily mean planning for one common nature. Understanding and working...

  17. Discover the Nile River

    Science.gov (United States)

    Project WET Foundation, 2009

    2009-01-01

    Bordering on the Fantastic. As the longest river on earth, the Nile passes through 10 countries. Presented through a wide range of activities and a winning array of games, it's also unsurpassed at taking young minds into exploring the world of water, as well as natural and man made wonders.

  18. Coupled effects of natural and anthropogenic controls on seasonal and spatial variations of river water quality during baseflow in a coastal watershed of Southeast China

    National Research Council Canada - National Science Library

    Huang, Jinliang; Huang, Yaling; Zhang, Zhenyu

    2014-01-01

    .... Anthropogenic input related to industrial effluents and domestic wastewater, agricultural activities associated with the precipitation-induced surface runoff, and natural weathering process were...

  19. Effect of the pollution level on the functional bacterial groups aiming at degrading bisphenol A and nonylphenol in natural biofilms of an urban river.

    Science.gov (United States)

    Cai, Wei; Li, Yi; Wang, Peifang; Niu, Lihua; Zhang, Wenlong; Wang, Chao

    2016-08-01

    Bisphenol A (BPA) and 4-nonylphenol (NP) are ubiquitous pollutants with estrogenic activity in aquatic environment and have attracted global concern due to their disruption of endocrine systems. This study investigated the spatial distribution characteristics of the bacterial groups involved in the degradation of BPA and NP within biofilms in an urban river using terminal restriction fragment length polymorphism based on 16S rRNA gene sequences. The effects of the pollution level and water parameters on these groups were also assessed. Hierarchical cluster analysis grouped the sampling sites into three clusters reflecting their varying nutrient pollution levels of relatively slight pollution (SP), moderate pollution (MP), and high pollution (HP) based on water quality data and Environmental Quality Standard for Surface Water of China (GB3838-2002). The BPA and NP concentration in river water ranged from 0.8 to 77.5 and 10.2 to 162.9 ng L(-1), respectively. Comamonadaceae, Pseudomonadaceae, Alcaligenaceae, Bacillaceae, Sphingomonadacea, Burkholderiaceae, and Rhizobiaceae were the dominant bacterial taxa involved in BPA and NP degradation, comprising an average of 9.8, 8.1, 7.6, 6.7, 6.2, 4.1, and 2.8 % of total sequences, respectively. The total abundance of these groups showed a slight upward trend and subsequently rapidly decreased with increasing pollution levels. The average proportion of Comamonadaceae in MP river sections was almost 1.5-2 times than that in SP or HP one. The distribution of functional groups was found related to environmental variables, especially pH, conductivity, ammonium nitrogen (NH3-N), and BPA. The abundance of Comamonadaceae and Rhizobiaceae was both closely related to higher values of pH and conductivity as well as lower concentrations of NP and BPA. Alcaligenaceae and Pseudomonadaceae were associated with higher concentrations of TP and CODMn and inversely correlated with DO concentration. This study might provide effective data on

  20. Re-Os geochronology and Os isotope fingerprinting of petroleum sourced from a Type I lacustrine kerogen: insights from the natural Green River petroleum system in the Uinta Basin and hydrous pyrolysis experiments

    Science.gov (United States)

    Cumming, Vivien M.; Selby, David; Lillis, Paul G.; Lewan, Michael D.

    2014-01-01

    Rhenium–osmium (Re–Os) geochronology of marine petroleum systems has allowed the determination of the depositional age of source rocks as well as the timing of petroleum generation. In addition, Os isotopes have been applied as a fingerprinting tool to correlate oil to its source unit. To date, only classic marine petroleum systems have been studied. Here we present Re–Os geochronology and Os isotope fingerprinting of different petroleum phases (oils, tar sands and gilsonite) derived from the lacustrine Green River petroleum system in the Uinta Basin, USA. In addition we use an experimental approach, hydrous pyrolysis experiments, to compare to the Re–Os data of naturally generated petroleum in order to further understand the mechanisms of Re and Os transfer to petroleum. The Re–Os geochronology of petroleum from the lacustrine Green River petroleum system (19 ± 14 Ma – all petroleum phases) broadly agrees with previous petroleum generation basin models (∼25 Ma) suggesting that Re–Os geochronology of variable petroleum phases derived from lacustrine Type I kerogen has similar systematics to Type II kerogen (e.g., Selby and Creaser, 2005a, Selby and Creaser, 2005b and Finlay et al., 2010). However, the large uncertainties (over 100% in some cases) produced for the petroleum Re–Os geochronology are a result of multiple generation events occurring through a ∼3000-m thick source unit that creates a mixture of initial Os isotope compositions in the produced petroleum phases. The 187Os/188Os values for the petroleum and source rocks at the time of oil generation vary from 1.4 to 1.9, with the mode at ∼1.6. Oil-to-source correlation using Os isotopes is consistent with previous correlation studies in the Green River petroleum system, and illustrates the potential utility of Os isotopes to characterize the spatial variations within a petroleum system. Hydrous pyrolysis experiments on the Green River Formation source rocks show that Re and Os transfer

  1. Post-Release Attributes and Survival of Hatchery and Natural Fall Chinook Salmon in the Snake River; 2000-2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Connor, William P. (US Fish and Wildlife Service, Idaho Fishery Resource Office, Ahsahka, ID)

    2003-02-01

    This report summarizes results of research activities conducted in 2000, 2001, and years previous to aid in the management and recovery of fall chinook salmon in the Columbia River basin. The report is divided into sections and self-standing chapters. For detailed summaries, we refer the reader to the abstracts given on the second page of each chapter. The Annual Reporting section includes information provided to fishery managers in-season and post-season, and it contains a detailed summary of life history and survival statistics on wild Snake River fall chinook salmon juveniles for the years 1992-2001. The Journal Manuscripts section includes complete copies of papers submitted or published during 2000 and 2001 that were not included in previous annual reports. Publication is a high priority for this project because it provides our results to a wide audience, it ensures that our work meets high scientific standards, and we believe that it is a necessary obligation of a research project. The Bibliography of Published Journal Articles section provides citations for peer-reviewed papers co-authored by personnel of project 199102900 that were published from 1998 to 2001.

  2. Anthropogenic impacts on global organic river pollution

    NARCIS (Netherlands)

    Wen, Y.

    2017-01-01

    Organic pollution of rivers by wastewater discharge from human activities negatively impacts people and ecosystems. Without treatment, pollution control relies on a combination of natural degradation and dilution by natural runoff to reduce downstream effects. To implement integrated water

  3. River nomads

    DEFF Research Database (Denmark)

    2016-01-01

    River nomads is a movie about people on the move. The documentary film explores the lifestyle of a group of nomadic fishermen whose mobility has been the recipe of success and troubles. Engaged in trade and travel, twice a year the river nomads form impressive convoys of majestic pirogues and set...... and liberated lifestyle and the breath-taking landscapes and vistas offered by the Niger River. River Nomads is also a personal account of the Kebbawa’s way of life and their current struggles as nomadic folk living in a world divided by borders and ruled by bureaucrats....

  4. A comparison of the survival and migratory behavior of hatchery-reared and naturally reared steelhead smolts in the Alsea river and estuary, Oregon, using acoustic telemetry

    Science.gov (United States)

    We tracked three groups of steelhead Oncorhynchus mykiss smolts implanted with acoustic transmitters to determine whether the degree of hatchery domestication or the juvenile rearing environment (hatchery raceway versus natural stream) influenced migration timing and survival in ...

  5. Geographical Distribution of Disasters Caused by Natural Hazards in Data-scarce Areas : Methodological exploration on the Samala River catchment, Guatemala

    OpenAIRE

    Soto Gómez, Agnes Jane

    2015-01-01

    An increasing trend in both the number of disasters and affected people has been observed, especially during the second half of the 20th century. The physical, economic and social impact that natural hazards have had on a global scale has prompted an increasing interest of governments, international institutions and the academia. This has immensely contributed to improve the knowledge on the subject and has helped multiply the number of initiatives to reduce the negative consequences of natur...

  6. Implementing Integrated River Basin Management in China

    NARCIS (Netherlands)

    Boekhorst, D.G.J. te; Smits, A.J.M.; Yu, X.; Lifeng, L.; Lei, G.; Zhang, C.

    2010-01-01

    This paper examines the role of the World Wildlife Fund for Nature China as policy entrepreneur in China. It illustrates the ways in which the World Wildlife Fund for Nature is active in promoting integrated river basin management in the Yangtze River basin and how the efforts at basin level are

  7. Geomorphology and River Management

    Directory of Open Access Journals (Sweden)

    GARY BRIERLEY

    2008-01-01

    Full Text Available Engineering-dominated practices, visible in a "command and control" outlook on natural systems, have induced enormous damage to the environment. Biodiversity losses and declining provision of ecosystem services are testimony to the non-sustainable outcomes brought about by such practices. More environmentally friendly approaches that promote a harmonious relationship between human activities and nature are required. Moves towards an "ecosystem approach" to environmental management require coherent (integrative scientific guidance. Geomorphology, the study of the form of the earth, provides a landscape template with which to ground this process. This way of thinking respects the inherent diversity and complexity of natural systems. Examples of the transition toward such views in environmental practice are demonstrated by the use of science to guide river management, emphasising applications of the River Styles framework.

  8. Development of a sensitive and robust online dual column liquid chromatography-tandem mass spectrometry method for the analysis of natural and synthetic estrogens and their conjugates in river water and wastewater.

    Science.gov (United States)

    Čelić, Mira; Insa, Sara; Škrbić, Biljana; Petrović, Mira

    2017-09-01

    An online ultra-high-performance-liquid chromatography-triple quadrupole tandem mass spectrometry (UHPLC-MS/MS) method for detection and quantification of natural and synthetic estrogens and their conjugates in aqueous matrices was developed. Target compounds include the natural estrogen estradiol (E2) and its main metabolites estrone (E1) and estriol (E3), the synthetic estrogens ethinylestradiol (EE2) and diethylstilbestrol (DES) and their conjugates estrone 3-sulfate (E1-3S), estriol 3-sulfate (E3-3S), estradiol 17-glucuronide (E2-17G), estrone 3-glucuronide (E1-3G), and estriol 16-glucuronide (E3-16G). After pH adjustment, sample filtration and addition of internal standards (IS), water samples (5 mL) were preconcentrated on a Hypersil GOLD aQ column after which chromatographic separation was achieved on a Kinetex C18 column using methanol and water as a mobile phase. The experimental parameters, such as sample loading flow rate, elution time, the percentage of organic solvent in the aqueous-organic eluent mixture, pH, and volume of analyzed samples, were optimized in detail. The benefits of the method compared to previously published methods include minimum sample manipulation, lower detection limits, reduced total analysis time, and overall increased method accuracy and precision. Method detection limits (MDLs) are in subnanogram per liter, complying with the requirements of the EC Decision 2015/495 (Watch list) for hormones listed therein. Applicability of the developed method was confirmed by analysis of river and raw wastewater samples taken directly from urban sewerage systems before being discharged into the river. Graphical abstract Sheme of online SPE-UHPLC-MS/MS system.

  9. Modeling and assessing the function and sustainability of natural patches in salt-affected agro-ecosystems: Application to tamarisk (Tamarix chinensis Lour.) in Hetao, upper Yellow River basin

    Science.gov (United States)

    Ren, Dongyang; Xu, Xu; Ramos, Tiago B.; Huang, Quanzhong; Huo, Zailin; Huang, Guanhua

    2017-09-01

    Relatively low-lying zones of natural vegetation within irrigated areas are not only carriers of biodiversity but also dry drainage areas of excess water and salts applied to nearby croplands. It is thus useful to have a correct understanding of the soil water-salt dynamics and plant water use for keeping the sustainability of those natural areas. The HYDRUS-dualKc model that couples the HYDRUS-1D model with the FAO-56 dualKc approach was extended to simulate the eco-hydrological processes in natural patches of Hetao Irrigation District (Hetao), upper Yellow River basin. Field experiments were conducted in a tamarisk (Tamarix chinensis Lour.) dominated area during the growing seasons of 2012 and 2013. The model was calibrated and validated using the two-year experimental data, and applied to analyze the water and salt dynamics and the tamarisk water consumption for the present situation. Then, various groundwater depth (i.e. the depth from groundwater surface to water table, GWD) scenarios were simulated while considering the fluctuating and constant regimes of GWD changes, as well as variations of the rooting depth. Results indicated that this natural land functioned efficiently as a drainage area for subsurface flow and excess salt from surrounding croplands. However, the present GWDs were too shallow leading to high soil evaporation and severe salt stress. The soil evaporation accounted for 50% of the total evapotranspiration (ETa) while root zone salt storage increased about 50% during growing seasons. On the basis of scenario analysis, an optimum groundwater depth of 140-200 cm with smaller fluctuation was suggested for the growing seasons of natural patches. In addition, tamarisk growth could be largely improved if the roots can grow deeper with water table decline in the future. We demonstrated that monitoring and modeling could be used to support the development of water management strategies in Hetao aimed at conserving water while sustaining local

  10. River Piracy

    Indian Academy of Sciences (India)

    . Asiatic Soc. o/Bengal., 55:322-343.1886. C F Oldham. The Saraswati and the lost river of the Indian desertJ. R. Asiatic. Soc., 34:49-76. 1893. S C Sharma. The description of rivers in the Rigveda, The Geographical. Observer, 10:79-85. 1974.

  11. Ocorrência de infecção natural de Fasciola hepatica Linnaeus, 1758 em Lymnaea columella Say, 1817 no Vale do Paraíba, SP, Brasil Natural infection by Fasciola hepatica in Lymnaea columella in the Paraíba river valley, S. Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Marlene Tiduko Ueta

    1980-06-01

    Full Text Available Foram registradas em Piquete, no vale do rio Paraíba do Sul (SP, Brasil, taxas de 1,22% e 0,14% de infecção natural em Lymnaea columella, por Fasciola hepatica. Em um único exemplar de Lymnaea columella dentre os 1.052 examinados, foram observadas rédias com xifidiocercárias, rédias com cercárias de Fasciola hepatica e metacercárias de Echinostomatidae.Infection rates of 1.22% and 0.14% were obtained in Lymnaea columella snails naturally infected by Fasciola hepatica. Samples of the snails were collected in Piquete, a municipality of Paraíba do Sul, a river valley area in the State of S. Paulo. Also observed was one of the 1052 specimen of the Lymnaea columella rediae which had xiphidiocercariae and rediae with Fasciola hepatica cercariae and metacercariae of Echinostomatidae.

  12. Rehabilitating China's largest inland river.

    Science.gov (United States)

    Li, Yiqing; Chen, Yaning; Zhang, Yaoqi; Xia, Yang

    2009-06-01

    Wetlands are particularly important for conserving China's biodiversity but riparian wetlands in the Tarim River basin in western China have been reduced by 46% during the last 3 decades. The world's largest habitat for Populus euphratica, which is in the Tarim River basin, significantly shrank. To protect and restore the deteriorated ecosystems along the Tarim River and its associated wetlands, China's government initiated a multimillion dollar river restoration project to release water from upper dams to the dried-up lower reaches of the Tarim River starting in 2000. We monitored the responses of groundwater and vegetation to water recharge in the lower reaches of the river from 2000 to 2006 by establishing nine 1000-m-long transects perpendicular to the river at intervals of 20-45 km along the 320-km river course below the Daxihaizi Reservoir, the source of water conveyance, to Lake Taitema, the terminus of the Tarim River. Water recharges from the Daxihaizi Reservoir to the lower reaches of the Tarim River significantly increased groundwater levels and vegetation coverage at all monitoring sites along the river. The mean canopy size of the endangered plant species P. euphratica doubled after 6 years of water recharge. Some rare migrating birds returned to rest on the restored wetlands in summer along the lower reaches of the Tarim River. The biggest challenge facing decision makers, however, is to balance water allocation and water rights between agricultural and natural ecosystems in a sustainable way. A large number of inhabitants in the Tarim Basin depend on these limited water resources for a living. At the same time, the endangered ecosystems need to be protected. Given the ecological, socioeconomic, and sociopolitical realities in the Tarim Basin, adaptive water policies and strategies are needed for water allocation in these areas of limited water resources. ©2009 Society for Conservation Biology.

  13. Flooding in river mouths: human caused or natural events? Five centuries of flooding events in the SW Netherlands, 1500-2000

    NARCIS (Netherlands)

    de Kraker, A.M.J.

    2015-01-01

    This paper looks into flood events of the past 500 years in the SW Netherlands, addressing the issue of what kind of flooding events have occurred and which ones have mainly natural causes and which ones are predominantly human induced. The flood events are classified into two major categories: (a)

  14. The reactive surface of Castor leaf [Ricinus communis L.] powder as a green adsorbent for the removal of heavy metals from natural river water

    Science.gov (United States)

    Martins, Amanda E.; Pereira, Milene S.; Jorgetto, Alexandre O.; Martines, Marco A. U.; Silva, Rafael I. V.; Saeki, Margarida J.; Castro, Gustavo R.

    2013-07-01

    In this study, a green adsorbent was successfully applied to remove toxic metals from aqueous solutions. Dried minced castor leaves were fractionated into 63-μm particles to perform characterization and extraction experiments. Absorption bands in FTIR (Fourier Transform Infrared Spectroscopy) spectra at 1544, 1232 and 1350 cm-1 were assigned to nitrogen-containing groups. Elemental analysis showed high nitrogen and sulfur content: 5.76 and 1.93%, respectively. The adsorption kinetics for Cd(II) and Pb(II) followed a pseudo-second-order model, and no difference between the experimental and calculated Nf values (0.094 and 0.05 mmol g-1 for Cd(II) and Pb(II), respectively) was observed. The Ns values calculated using the modified Langmuir equation, 0.340 and 0.327 mmol g-1 for Cd(II) and Pb(II), respectively, were superior to the results obtained for several materials in the literature. The method proposed in this study was applied to pre-concentrate (45-fold enrichment factor) and used to measure Cd(II) and Pb(II) in freshwater samples from the Paraná River. The method was validated through a comparative analysis with a standard reference material (1643e).

  15. Assessing wildlife benefits and carbon storage from restored and natural coastal marshes in the Nisqually River Delta: Determining marsh net ecosystem carbon balance

    Science.gov (United States)

    Anderson, Frank; Bergamaschi, Brian; Windham-Myers, Lisamarie; Woo, Isa; De La Cruz, Susan; Drexler, Judith; Byrd, Kristin; Thorne, Karen M.

    2016-06-24

    Working in partnership since 1996, the U.S. Fish and Wildlife Service and the Nisqually Indian Tribe have restored 902 acres of tidally influenced coastal marsh in the Nisqually River Delta (NRD), making it the largest estuary-restoration project in the Pacific Northwest to date. Marsh restoration increases the capacity of the estuary to support a diversity of wildlife species. Restoration also increases carbon (C) production of marsh plant communities that support food webs for wildlife and can help mitigate climate change through long-term C storage in marsh soils.In 2015, an interdisciplinary team of U.S. Geological Survey (USGS) researchers began to study the benefits of carbon for wetland wildlife and storage in the NRD. Our primary goals are (1) to identify the relative importance of the different carbon sources that support juvenile chinook (Oncorhynchus tshawytscha) food webs and contribute to current and historic peat formation, (2) to determine the net ecosystem carbon balance (NECB) in a reference marsh and a restoration marsh site, and (3) to model the sustainability of the reference and restoration marshes under projected sea-level rise conditions along with historical vegetation change. In this fact sheet, we focus on the main C sources and exchanges to determine NECB, including carbon dioxide (CO2) uptake through plant photosynthesis, the loss of CO2 through plant and soil respiration, emissions of methane (CH4), and the lateral movement or leaching loss of C in tidal waters.

  16. Structure and Composition of Vegetation on Longleaf Plantation Sites Compared to Natural Stands Occurring Along an Environmental Gradient at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.P.

    2000-10-01

    The diversity and abundance of native grasses and herbaceous species characteristic of the longleaf savanna were compared between remnant stands that were not previously under agriculture and recent old-fields.The objective of the study was to establish a baseline for future restoration objectives and to compare the degree of degradation associated with agriculture. In most cases even the natural stands have suffered degradation as a result of fire exclusion and as such are not representative of pristine conditions. Community classification and ordination procedures were implemented to array the communities. Three distinct sub-units were identified and associated with xeric, sub-xeric, and medic types associated with texture and soil moisture. Between plantations and natural stands, the xeric group demonstrated the most similarity. The presence of a B horizon was the most important discriminate variable in both groups.

  17. RESOURCE CHARACTERIZATION AND QUANTIFICATION OF NATURAL GAS-HYDRATE AND ASSOCIATED FREE-GAS ACCUMULATIONS IN THE PRUDHOE BAY - KUPARUK RIVER AREA ON THE NORTH SLOPE OF ALASKA

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hunter; Shirish Patil; Robert Casavant; Tim Collett

    2003-06-02

    Interim results are presented from the project designed to characterize, quantify, and determine the commercial feasibility of Alaska North Slope (ANS) gas-hydrate and associated free-gas resources in the Prudhoe Bay Unit (PBU), Kuparuk River Unit (KRU), and Milne Point Unit (MPU) areas. This collaborative research will provide practical input to reservoir and economic models, determine the technical feasibility of gas hydrate production, and influence future exploration and field extension of this potential ANS resource. The large magnitude of unconventional in-place gas (40-100 TCF) and conventional ANS gas commercialization evaluation creates industry-DOE alignment to assess this potential resource. This region uniquely combines known gas hydrate presence and existing production infrastructure. Many technical, economical, environmental, and safety issues require resolution before enabling gas hydrate commercial production. Gas hydrate energy resource potential has been studied for nearly three decades. However, this knowledge has not been applied to practical ANS gas hydrate resource development. ANS gas hydrate and associated free gas reservoirs are being studied to determine reservoir extent, stratigraphy, structure, continuity, quality, variability, and geophysical and petrophysical property distribution. Phase 1 will characterize reservoirs, lead to recoverable reserve and commercial potential estimates, and define procedures for gas hydrate drilling, data acquisition, completion, and production. Phases 2 and 3 will integrate well, core, log, and long-term production test data from additional wells, if justified by results from prior phases. The project could lead to future ANS gas hydrate pilot development. This project will help solve technical and economic issues to enable government and industry to make informed decisions regarding future commercialization of unconventional gas-hydrate resources.

  18. The Columbia River System Inside Story

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-04-01

    The Columbia River is one of the greatest natural resources in the western United States. The river and its tributaries touch the lives of nearly every resident of the Pacific Northwest—from fostering world-famous Pacific salmon to supplying clean natural fuel for 50 to 65 percent of the region’s electrical generation. Since early in the 20th century, public and private agencies have labored to capture the benefits of this dynamic river. Today, dozens of major water resource projects throughout the region are fed by the waters of the Columbia Basin river system.

  19. Genetic differences between hatchery and wild steelhead for survival, growth, dispersal, and male maturation in a natural stream (Study site: Twenty-Mile Creek; Stocks: Dworshak hatchery and Selway River wild; Year classes: 1994 and 1995): Chapter 3

    Science.gov (United States)

    Rubin, Stephen P.; Reisenbichler, Reginald R.; Hensleigh, Jay E.; Wetzel, Lisa A.; Baker, Bruce M.; Leonetti,; Stenberg, Karl D.; Slatton, Stacey L.; Rubin, Stephen P.; Reisenbichler, Reginald R.; Wetzel, Lisa A.; Hayes, Michael C.

    2012-01-01

    This study was initiated in the early 1990s to provide managers with data comparing genetic fitness for natural rearing, as measured by survival of juveniles in freshwater, between steelhead Oncorhynchus mykiss from Dworshak National Fish Hatchery and wild steelhead from the Clearwater River, Idaho. We artificially spawned hatchery steelhead and wild steelhead from the Selway River, a Clearwater River tributary, released the resulting genetically marked (at the PEPA allozyme locus) progeny (HxH, HxW from hatchery females and wild males, and WxW) as unfed fry in a second order tributary of the South Fork Clearwater River, and monitored fish residing in the stream or emigrating from it for five years. Barrier falls prevented access to the stream by naturally produced steelhead. Over 90% of the emigrants were one or two years of age and too small to be smolts (mean fork length at age-2 = 103 mm). Per fry released, the HxH cross produced 0.64-0.83 times as many emigrants as the WxW cross (P<0.05). The HxH cross produced 0.63 times as many age-4 residuals as the WxW cross for one year-class (P=0.051) and 0.68 times as many for the other (ns). Survival from age-1 to age-4 was lower for HxH than for WxW residuals of one year-class (P<0.05) and survival from age-2 to age-4 may have been lower for HxH than for WxW residuals of the other (P=0.062). Collectively, these results indicate lower survival for HxH than for WxW fish. Size was often greater for HxH than for WxW fish indicating faster growth for the former, and condition factor was also usually greater for HxH than for WxW fish. Dispersal of fry from release sites and emigration of one- and two-year olds from the study stream were greater for WxW than for HxH fish, and apparently neither was from competitive displacement of small by larger fish. Incidence of flowing milt was higher for HxH than for WxW fish at age-2. Peak incidence of flowing milt for older residuals was similar among crosses (about 50%), but the peak

  20. Natural Arsenic in the Miocene Hawthorn Group, Florida: Wide Ranging Implications for ASR, Phosphate Mining, Private Well

    Science.gov (United States)

    Lazareva, O. V.; Pichler, T.

    2004-12-01

    organic material, clays, and iron oxides contain lower As concentrations contrasted to pyrite; (5) Pyrite occurs in framboidal and euhedral forms. Because phosphorous, arsenic and sulfur are chemically closely related, they often occur together in nature, thus posing a potential problem for the phosphate industry. There have been several occurrences of swine fatalities due to arsenic poisoning as a result of phosphate feed supplements. Information about the concentration, distribution and mineralogical association of naturally occurring As is important, because this is a first step to forecast its behavior during anthropogenic induced physico-chemical changes in the aquifer. Recently, aquifer storage and recovery (ASR) facilities in central Florida reported As concentrations in excess of 100 μ g/L in recovered water. The ASR storage zone is the Suwannee Limestone, which directly underlies the Hawthorn sediments. It is crucial to the future of ASR in this area to understand the source and distribution of arsenic in the overlying Hawthorn Group and the cycling of arsenic in the Florida platform.

  1. Health evaluation indicator system for urban landscape rivers, case study of the Bailianjing River in Shanghai

    Science.gov (United States)

    Wang, Juan; Wang, Yue; Yang, Haizhen; Lu, Zhibo; Xu, Xiaotian

    2010-11-01

    The River Bailianjing is an iconic landscape feature known to all residents in Pudong area and running through the Shanghai Expo 2010 Park. The river and its basin was a complex living ecosystem which supports a unique variety of flora and fauna several decades ago. However, as a result of unsuccessful pollution source control, sewage and first flow of the storm water is directly coming into the river in some catchment. The water quality of the river is seriously organically polluted now. The typical organic pollutants are COD, NH3-N, TN and TP, which cause the extinction of the water plants and aquatic. Furthermore, the artificial hard river banks isolate the river course and the land, which damaged the whole ecological system totally. The nature of the River Bailianjing and its history has resulted in many government departments and authorities and non government organizations having jurisdiction and/or an interest in the river's management. As a new tool to improve river management, the river health assessment has become the major focus of ecological and environmental science. Consequently, research on river health evaluation and its development on river management are of great theoretical and practical significance. In order to evaluate the healthy status of the River Bailianjing and prepare comprehensive scientific background data for the integrated river ecological rehabilitation planning, the health evaluation indicator system for River Bailianjing is brought forward. The indicator system has three levels: the first is target layer; the second is criteria layer, including five fields: water quality characteristics, hydrology characteristics, river morphology, biological characteristics and river scenic beauty; the third is an index layer, a total of 15 specific indicators included. Fuzzy AHP method is used to evaluate the target river's health status, and five grades are set up to describe it: healthy, sub health, marginal, unhealthy and pathological. The

  2. The river research programme

    CSIR Research Space (South Africa)

    Ferrar, AA

    1988-01-01

    Full Text Available reference to the ecological needs of aquatic ecosystems. No acknowledgement of any social or economic cost for the degradation of aquatic ecosystems as a result of water abstraction is made in the Commission's report except for certain nature reserves... for water means that all our substantial river systems will be subject to water regulation and abstraction and to the introduction of pollutants. Conservation management therefore becomes an exercise in mitigation. The principal tools are, legislation...

  3. Sustainable agriculture and nitrogen reduction: an open field experiment using natural zeolitites in silty-clay reclaimed soil at Codigoro (Po River Delta, Ferrara, Italy)

    Science.gov (United States)

    Faccini, Barbara; Di Giuseppe, Dario; Mastrocicco, Micòl; Coltorti, Massimo; Colombani, Nicolò; Ferretti, Giacomo

    2014-05-01

    Following the guidelines of Nitrate and Water Framework Directives (91/676/CEE, 200/60/CE) an innovative integrated zeolitite cycle is being tested on a reclaimed clayey-silt soil in the Po Delta area (Ferrara Province, Italy), in the framework of the EU-funded ZeoLIFE project (LIFE+10 ENV/IT/000321). Natural zeolitites are pyroclastic rocks containing more than 50% of zeolites, a kind of hydrous minerals with peculiar physical and chemical properties, like high and selective cation exchange capacity (CEC), molecular adsorption and reversible dehydration. Zeolitites can trap NH4+ from solutions and release it gradually to the plant roots once they have been mixed in agricultural soils, allowing both fertilization and irrigation reduction and improvement of the yield. The fertilization reduction can result in a decrease of the nitrate content in groundwater and surface waters, ultimately leading to a mitigation of nutrient excess in the environment. Similarly, reduction of irrigation water means a minor exploitation of the water resource. The selected material used in the project is a chabazite zeolitite coming from a quarry near Sorano in Central Italy (Bolsena volcanic district). The open-field experimentation foresees two year of cultivation. A surface of about 6 ha has been divided into six parcels: three control parcels are cultivated and irrigated in traditional way; two parcels have been added with coarse-grained (ø = 3- 6 mm) natural zeolitite at different zeolitite/soil ratios (5 kg/m2 and 15 kg/m2) and one has been mixed with fine-grained (ø irrigation system installed in the field. An automated meteorological station has been also installed in order to quantify rainfalls and sun irradiation for water balance calculation. During the first year, a no-food variety of sorghum has been cultivated. In the parcels treated with natural zeolitite and in that bearing NH4+-charged zeolitite, the fertilization has been reduced by 30% and 50% with respect to the

  4. River meander modeling of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois

    Science.gov (United States)

    Lant, Jeremiah G.; Boldt, Justin A.

    2018-01-16

    Natural river channels continually evolve and change shape over time. As a result, channel evolution or migration can cause problems for bridge structures that are fixed in the flood plain. A once-stable bridge structure that was uninfluenced by a river’s shape could be encroached upon by a migrating river channel. The potential effect of the actively meandering Wabash River on the Interstate 64 Bridge at the border with Indiana near Grayville, Illinois, was studied using a river migration model called RVR Meander. RVR Meander is a toolbox that can be used to model river channel meander migration with physically based bank erosion methods. This study assesses the Wabash River meandering processes through predictive modeling of natural meandering over the next 100 years, climate change effects through increased river flows, and bank protection measures near the Interstate 64 Bridge.

  5. Productivity and phenological responses of natural vegetation to present and future inter-annual climate variability across semi-arid river basins in Chile.

    Science.gov (United States)

    Glade, Francisco E; Miranda, Marcelo D; Meza, Francisco J; van Leeuwen, Willem J D

    2016-12-01

    Time series of vegetation indices and remotely sensed phenological data offer insights about the patterns in vegetation dynamics. Both are useful sources of information for analyzing and monitoring ecosystem responses to environmental variations caused by natural and anthropogenic drivers. In the semi-arid region of Chile, climate variability and recent severe droughts in addition to land-use changes pose threats to the stability of local ecosystems. Normalized difference vegetation index time series (2000-2013) data from the moderate resolution imaging spectroradiometer (MODIS) was processed to monitor the trends and patterns of vegetation productivity and phenology observed over the last decade. An analysis of the relationship between (i) vegetation productivity and (ii) precipitation and temperature data for representative natural land-use cover classes was made. Using these data and ground measurements, productivity estimates were projected for two climate change scenarios (RCP2.6 and RCP8.5) at two altitudinal levels. Results showed negative trends of vegetation productivity below 2000 m a.s.l. and positive trends for higher elevations. Phenology analysis suggested that mountainous ecosystems were starting their growing period earlier in the season, coinciding with a decreased productivity peak during the growing season. The coastal shrubland/grassland land cover class had a significant positive relation with rainfall and a significant negative relation with temperature, suggesting that these ecosystems are vulnerable to climate change. Future productivity projections indicate that under an RCP8.5 climate change scenario, productivity could decline by 12% in the period of 2060-2100, leading to a severe vegetation degradation at lower altitudes and in drier areas.

  6. Resource Characterization and Quantification of Natural Gas-Hydrate and Associated Free-Gas Accumulations in the Prudhoe Bay - Kuparuk River Area on the North Slope of Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Shirish Patil; Abhijit Dandekar

    2008-12-31

    Natural gas hydrates have long been considered a nuisance by the petroleum industry. Hydrates have been hazards to drilling crews, with blowouts a common occurrence if not properly accounted for in drilling plans. In gas pipelines, hydrates have formed plugs if gas was not properly dehydrated. Removing these plugs has been an expensive and time-consuming process. Recently, however, due to the geologic evidence indicating that in situ hydrates could potentially be a vast energy resource of the future, research efforts have been undertaken to explore how natural gas from hydrates might be produced. This study investigates the relative permeability of methane and brine in hydrate-bearing Alaska North Slope core samples. In February 2007, core samples were taken from the Mt. Elbert site situated between the Prudhoe Bay and Kuparuk oil fields on the Alaska North Slope. Core plugs from those core samples have been used as a platform to form hydrates and perform unsteady-steady-state displacement relative permeability experiments. The absolute permeability of Mt. Elbert core samples determined by Omni Labs was also validated as part of this study. Data taken with experimental apparatuses at the University of Alaska Fairbanks, ConocoPhillips laboratories at the Bartlesville Technology Center, and at the Arctic Slope Regional Corporation's facilities in Anchorage, Alaska, provided the basis for this study. This study finds that many difficulties inhibit the ability to obtain relative permeability data in porous media-containing hydrates. Difficulties include handling unconsolidated cores during initial core preparation work, forming hydrates in the core in such a way that promotes flow of both brine and methane, and obtaining simultaneous two-phase flow of brine and methane necessary to quantify relative permeability using unsteady-steady-state displacement methods.

  7. In situ measurements of microbially-catalyzed nitrification and nitrate reduction rates in an ephemeral drainage channel receiving water from coalbed natural gas discharge, Powder River Basin, Wyoming, USA

    Science.gov (United States)

    Harris, S.H.; Smith, R.L.

    2009-01-01

    Nitrification and nitrate reduction were examined in an ephemeral drainage channel receiving discharge from coalbed natural gas (CBNG) production wells in the Powder River Basin, Wyoming. CBNG co-produced water typically contains dissolved inorganic nitrogen (DIN), primarily as ammonium. In this study, a substantial portion of discharged ammonium was oxidized within 50??m of downstream transport, but speciation was markedly influenced by diel fluctuations in dissolved oxygen (> 300????M). After 300??m of transport, 60% of the initial DIN load had been removed. The effect of benthic nitrogen-cycling processes on stream water chemistry was assessed at 2 locations within the stream channel using acrylic chambers to conduct short-term (2-6??h), in-stream incubations. The highest ambient DIN removal rates (2103????mol N m- 2 h- 1) were found at a location where ammonium concentrations > 350????M. This occurred during light incubations when oxygen concentrations were highest. Nitrification was occurring at the site, however, net accumulation of nitrate and nitrite accounted for nitrification was not a factor and changes in DIN removal rates were controlled by nitrate reduction, diel fluctuations in oxygen concentration, and availability of electron donor. This study indicates that short-term adaptation of stream channel processes can be effective for removing CBNG DIN loads given sufficient travel distances, but the long-term potential for nitrogen remobilization and nitrogen saturation remain to be determined.

  8. Experiments on sediment pulses in mountain rivers

    Science.gov (United States)

    Y. Cui; T. E. Lisle; J. E. Pizzuto; G. Parker

    1998-01-01

    Pulses of sediment can be introduced into mountain rivers from such mechanisms as debris flows, landslides and fans at tributary confluences. These processes can be natural or associated with the activities of humans, as in the case of a pulse created by sediment derived from timber harvest or the removal of a dam. How does the river digest these pulses?

  9. Towards a classification of Tanzanian rivers: a bioassessment and ...

    African Journals Online (AJOL)

    River classification is important for reporting ecological status and for the general ecological management of river systems by partitioning natural variability. A priori river classification by abiotic variables and validation of classifications obtained using aquatic macroinvertebrates from reference sites for selected Tanzanian ...

  10. RIVERS AND PORTS IN TRANSPORT HISTORY OF CAMEROON ...

    African Journals Online (AJOL)

    Dean SPGS NAU

    Abstract. In direct contrast to Europe, Asia and North America, Africa has very few navigable rivers. This paper focuses on the preponderant role played by water transport in the form of rivers and ports during the colonial period. Although not blessed with much navigable rivers and natural deep ports, the Colonial ...

  11. River Piracy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 5. River Piracy Saraswati that Disappeared. K S Valdiya. General Article Volume 1 Issue 5 May 1996 pp 19-28. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/05/0019-0028. Author Affiliations.

  12. PCBs in the Harlem River

    Science.gov (United States)

    Wang, J.

    2012-12-01

    Polychlorinated biphenyls (PCBs) are persistent, toxic and bioaccumulated contaminants of great environmental concern. PCB is a tracer of wastewater, stormwater and CSOs inputs; PCBs contamination of fish is a main environmental concern for the Harlem River. PCBs in the Harlem River are from combined sewer overflows (CSOs), stormwater runoff, wastewater, as well as upper Hudson GE (General Electric at Fort Edward)'s release. PCBs affect human health mostly from contaminated fish consumption. Many research focused on PCBs in the Hudson River and New York/New Jersey Harbor. However, PCBs source, transport and environmental impact in the Harlem River-a natural straight that connects the Hudson River and the East River, had not been well studied. In this research, water sample were collected from the Harlem River and analyzed PCBs by HR GC/MS (High resolution gas chromatography mass spectrophotometer). Preliminary results showed that certain PCBs congeners in the water column. Results also indicated that nutrients (phosphorus and ammonia) as well as bacteria levels exceeded EPA standards: Total phosphorus-10μg/L, total nitrogen-0.38mg/L; E.Coli-126 MPN/100ml, Enterococcus- 104MPN/100ml, Fecal Coliform-200 MPN/100ml. This research is under process, and more results could give further detail in near future. This research will help improve water quality of the Harlem River, improve environmental health and raise environmental awareness.SO tank Nutrient and bacterial levels of selected sites in the Harlem RiverCSO: Combined Sewer OverflowWWTP: Waste Water Treatment Plant

  13. DNR 100K Lakes and Rivers

    Data.gov (United States)

    Minnesota Department of Natural Resources — Polygons representing hydrographic features (lakes, ponds, some rivers, and open water areas) originating from the USGS 1:100,000 (100K)DLG (Digital Line Graph)...

  14. Anthropogenic Influence on the Dynamics of the River Lamprey Lampetra fluviatilis Landings in the River Daugava Basin

    Science.gov (United States)

    Birzaks, Janis; Abersons, Kaspars

    2011-01-01

    The construction of the Daugava hydro power station (HPS) cascade has significantly transformed Latvia's largest river the Daugava, reducing its importance in the natural reproduction of anadromous fish species. Currently in Latvia, as well as in other Baltic Sea countries, the river lamprey catch is decreasing, whereas the landings in the river Daugava have tended to increase. The dynamics of the river lamprey landings show the possible redistribution of lamprey stocks between the rivers Gauja and the Daugava. Possibly, this is a result of anthropogenic influence and changes in the river lamprey resource management may be necessary in the future.

  15. Investigating Photosensitized Properties of Natural Organic Matter and Effluent Organic Matter

    KAUST Repository

    Niu, Xi-Zhi

    2013-05-01

    The photosensitized processes significantly enhance photolysis of various chemicals in the aqueous system with dissolved organic matter (DOM) as sensitizer. The excitation of chromophores on the DOM molecule further generates reactive species as triplet states DOM, singlet oxygen, hydroxyl radical, carbonate radical etc. We investigated the photosensitization properties of Beaufort Fulvic Acid, Suwannee River Fulvic Acid, South Platte River Fulvic Acid, and Jeddah wastewater treatment plant effluent organic matter with a sunlight simulator. DOM photochemical properties were characterized by observing their performances in 3DOM*, singlet oxygen, hydroxyl radical production with indirect probing protocols. Sensitized degradation of 0.1 μM and 0.02 μM 2, 4, 6- Trimethylphenol exhibited higher pseudo-first-order rate constant than that of 10 μM. Pre-irradiated DOMs were found to be depressed in photochemical properties. Photolysis of 5 different contaminants: ibuprofen, bisphenol A, acetaminophen, cimetidine, and caffeine were found to be enhanced in the presence of sensitizers. The possible reaction pathways were revealed. Long time irradiance induced change in contaminants degradation kinetics in some DOM solutions, which was proposed to be due to the irradiation initiated indirect transformation of DOMs. Key Words: Photolysis Dissolved Organic Matter, Triplet State DOM, Singlet Oxygen, Hydroxyl Radical, Contaminants Degradation.

  16. Environmental flow for Monsoon Rivers in India: The Yamuna River as a case study

    CERN Document Server

    Soni, Vikram; Singh, Diwan

    2013-01-01

    We consider the flows of Monsoon Rivers in India that will permit the river to perform all its natural functions. About 80% of the total flow for Indian rivers is during the monsoon and the remaining 20% is during the non monsoon period. By carrying out a case study of the river Yamuna in Delhi we find that at least 50% of the virgin monsoon (July to September) flow is required for the transport of the full spectrum of soil particles in the river sediment. A similar flow is needed for adequate recharge of the floodplain aquifers along river. For the non monsoon period (October to June) about 60% of the virgin flow is necessary to avoid the growth of still water algae and to support river biodiversity.

  17. Antecedent Rivers

    Indian Academy of Sciences (India)

    far north of the high NandaDevi (7,817 m) - Api Nampa. (7,132 m) range of the Himadri. The Sindhu flows northwestwards, the Satluj goes west, the Karnali takes the southerly course and the Tsangpo flows east. These rivers flow through their pristine channels, carved out at the very outset about 50 to 55 m.y (million years) ...

  18. Natural organic matter differently modulates growth of two closely related coccal green algal species.

    Science.gov (United States)

    Karasyova, Tatyana A; Klose, Edgar O; Menzel, Ralph; Steinberg, Christian E W

    2007-03-01

    Humic substances (HS) comprise the majority of dead and living organic carbon, including organisms. In the environment, they are considered to be chemically inert or at least refractory. Recent papers, however, show that HS (including natural organic matter-NOM, isolated by reverse osmosis) are natural chemicals which interact with aquatic organisms. They are taken up and cause a variety of stress defense reactions which are well known from man-made chemicals. These reactions include chaperon activation, induction and modulation of biotrans-formation enzymes, or induction of antioxidant defense enzymes. One specific reaction with freshwater plants is the reduction of photosynthetic oxygen release. In this contribution, we compare the susceptibilities (cell yield) of two closely related coccal green algae, Monoraphidium convolutum and M. minutum, towards various NOM isolates. Cultures of M. convolutum and M. minutum were obtained from the algal collection of the Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, and from the Culture Collection of Algae, Göttingen, and maintained in a common medium. The cultures were non-axenic. The algae were exposed to 5 mg L(-1) DOC of each humic material, an environmentally realistic concentration. Cell numbers were counted microscopically in Neugebauer cuvettes in 5 replicates on days 1, 4, 7, 10, 14, and 21. Almost all NOM isolates modulated the growth of the algae. Only the NOM of a Norwegian raised peat bog lake did not reveal any significant effect with M. convolutuim. In general, the results with two algal species are by no means uniform. For instance, Suwannee River NOM causes a decrease in cell density with M. minutum, but temporarily stimulates the growth of M. convolutum. The opposite applies to Aurevann NOM: Growth increase in M. minutum, but a bi-phasic response in M. convolutum. Different responses of both Monoraphidium species must be attributed to intrinsic factors of the algae rather than only

  19. Assessment of water quality of a river-dominated estuary with hydrochemical parameters: A statistical approach.

    Digital Repository Service at National Institute of Oceanography (India)

    Padma, P.; Sheela, V.S.; Suryakumari, S.; Jayalakshmy, K.V.; Nair, S.M.; Kumar, N.C.

    in developmental and urbanization activ- ities, demands on our natural resources also shoot up and hence protection of rivers and estuaries for all their natural, economic and aesthetic values is very important (Song et al. 2011; USEPA 2012). When a river... or estuary is altered in its natural functions, it becomes polluted and can harm living beings. The rivers play a pivotal role in carrying industrial and urban wastes and this makes rivers more susceptible to environmental problems like pollution. Hence...

  20. Effect of the barrage and embankments on flooding and channel avulsion case study Koshi River, Nepal

    NARCIS (Netherlands)

    Devkota, L.; Crosato, A.; Giri, S.

    2012-01-01

    Humans have utilized water resources for millennia by modifying natural river courses and such interventions have greatly influenced not only river flows and sediment fluxes, but also the overall river morphology. Situated in the Nepal's eastern Ganges region, the braided Koshi River is unique among

  1. Implementing Integrated River Basin Management in China

    Directory of Open Access Journals (Sweden)

    Dorri G. J. te Boekhorst

    2010-06-01

    Full Text Available This paper examines the role of the World Wildlife Fund for Nature China as policy entrepreneur in China. It illustrates the ways in which the World Wildlife Fund for Nature is active in promoting integrated river basin management in the Yangtze River basin and how the efforts at basin level are matched with the advice of the China Council for International Cooperation on Environment and Development task force on integrated river basin management to the national government of China. This article demonstrates that the World Wildlife Fund for Nature uses various strategies of different types to support a transition process towards integrated river basin management. Successful deployment of these strategies for change in environmental policy requires special skills, actions, and attitudes on the part of the policy entrepreneur, especially in China, where the government has a dominant role regarding water management and the position of policy entrepeneurs is delicate.

  2. River otter component of the oiled mussel-bed study. Restoration study number 103-3. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    Energy Technology Data Exchange (ETDEWEB)

    Faro, J.B.; Bowyer, R.T.; Testa, J.W.; Duffy, L.K.

    1994-01-01

    The authors` objective was to determine if physiological and morphological differences previously detected in river otters from oiled and nonoiled areas could be affected by mussel beds, and whether these differences would persist or subside with time. Differences in levels of blood haptoglobin and Interleukin-6 ir, which previously were elevated in river otters (Lutra canadensis) inhabiting oiled when compared to nonoiled areas of Prince William Sound, Alaska, were not observed in summer 1992. River otters from oiled areas continued to regain body size from levels noted in 1990; adjusted mean body mass of otters from oiled and nonoiled areas were nearly identical by summer 1992. Consequently, no adverse effects in 1992 could be attributed to oiled mussel beds from areas where river otters were captured. Likewise, oiled mussel beds may not have been a factor contributing to documented differences in these variables in 1990 and 1991.

  3. Compromised Rivers: Understanding Historical Human Impacts on Rivers in the Context of Restoration

    Directory of Open Access Journals (Sweden)

    Ellen Wohl

    2005-12-01

    Full Text Available A river that preserves a simplified and attractive form may nevertheless have lost function. Loss of function in these rivers can occur because hydrologic and geomorphic processes no longer create and maintain the habitat and natural disturbance regimes necessary for ecosystem integrity. Recognition of compromised river function is particularly important in the context of river restoration, in which the public perception of a river's condition often drives the decision to undertake restoration as well as the decision about what type of restoration should be attempted. Determining the degree to which a river has been altered from its reference condition requires a knowledge of historical land use and the associated effects on rivers. Rivers of the Front Range of the Colorado Rocky Mountains in the United States are used to illustrate how historical land uses such as beaver trapping, placer mining, tie drives, flow regulation, and the construction of transportation corridors continue to affect contemporary river characteristics. Ignorance of regional land use and river history can lead to restoration that sets unrealistic goals because it is based on incorrect assumptions about a river's reference condition or about the influence of persistent land-use effects.

  4. River Corridor Easements

    Data.gov (United States)

    Vermont Center for Geographic Information — A River Corridor Easement (RCE) is an area of conserved land adjacent to a river or stream that was conserved to permanently protect the lateral area the river needs...

  5. Investigations into the Early Life History of Naturally Spring Chinook Salmon in the Grande Ronde River Basin : Fish Research Project Oregon : Annual Progress Report Project Period 1 September 1997 to 31 August 1998.

    Energy Technology Data Exchange (ETDEWEB)

    Keefe, MaryLouise; Tranquilli, J. Vincent

    1998-01-01

    We determined migration timing and abundance of juvenile spring chinook salmon from three populations in the Grande Ronde River basin. We estimated 6,716 juvenile chinook salmon left upper rearing areas of the Grande Ronde River from July 1997 to June 1998; approximately 6% of the migrants left in summer, 29% in fall, 2% in winter, and 63% in spring. We estimated 8,763 juvenile chinook salmon left upper rearing areas of Catherine Creek from July 1997 to June 1998; approximately 12% of the migrants left in summer, 37% in fall, 21% in winter, and 29% in spring. We estimated 8,859 juvenile chinook salmon left the Grande Ronde Valley, located below the upper rearing areas in Catherine Creek and the Grande Ronde River, from October 1997 to June 1998; approximately 99% of the migrants left in spring. We estimated 15,738 juvenile chinook salmon left upper rearing areas of the Lostine River from July 1997 to April 1998; approximately 3% of the migrants left in summer, 61% in fall, 2% in winter, and 34% in spring. We estimated 22,754 juvenile spring chinook salmon left the Wallowa Valley, located below the mouth of the Lostine River, from September 1997 to April 1998; approximately 55% of the migrants left in fall, 5% in winter, and 40% in spring. Juvenile chinook salmon PIT-tagged on the upper Grande Ronde River were detected at Lower Granite Dam from 4 April to 26 June 1998, with a median passage date of 1 May. PIT-tagged salmon from Catherine Creek were detected at Lower Granite Dam from 3 April to 26 June 1998, with a median passage date of 8 May. PIT-tagged salmon from the Lostine River were detected at Lower Granite Dam from 31 March through 26 May 1998, with a median passage date of 28 April. Juveniles tagged as they left the upper rearing areas of the Grande Ronde and Lostine rivers in fall and that overwintered in areas downstream were detected in the hydrosystem at a higher rate than fish tagged during winter in the upper rearing areas, indicating a higher

  6. Structural patterns in nature

    DEFF Research Database (Denmark)

    Wester, Ture

    2003-01-01

    It seemens that some very basic randomly produced geometric/topological patterns are commonly found in Nature and have often very distinctive structural qualities. In Nature we find the same pattern in all scales from the universe to molecules, from solar systems to packing of cells, from glaciers...... to sea shells, from river systems to trees etc. Sometimes this seeming archetypical morphology involve structrual action and sometimes not-but the fact that it often posses efficient structural action opens a tool for evaluation and analysis of structures in nature and at the same time might...

  7. CONTRIBUTIONS TO THE STUDY OF THE AVIFAUNA FROM THE SITE NATURE 2000 ROSPA0062 – “THE RESERVOIRS ON THE ARGEŞ RIVER” - THE WINTERING QUARTERS FROM THE MIDDLE BASIN OF THE ARGEŞ RIVER. THE HIEMAL SEASON.

    Directory of Open Access Journals (Sweden)

    Maria Denisa Conete

    2014-11-01

    Full Text Available In the present paper we present the results of our ecological research on the avifauna of some reservoirs (a site of the Nature 2000 Network from the middle basin of the Argeş River, during the hiemal season in the period 2003 – 2010. The hibernal/hiemal season is the poorest in species of the six seasons (118 species belonging to 14 orders, 32 families and 68 genera, of which 49 species are dependent on wetlands, but the richest in the number of individuals (448,064. We also perform an analysis of the avifauna according to ecological indices (IR, constancy, dominancy, the Dzuba index of ecological significance, etc.. The Anseriformes were overdominant. It is the only season in which the order Passeriformes is complementary. Great agglomerations of Anseriformes are constantly present during the hiemal season; the specific composition and the number of individuals of the different species vary continuously on each of the reservoirs in relation to the weather conditions, the accessibility of food, etc. The highest number of Anseriformes species was observed on the Budeasa Reservoir (19 species and the lowest on the Bascov Reservoir (12 species. The correlation between temperature and the total number of individuals of the bird species is negative. As the temperature increases, the number of individuals decreases and vice versa. The most important wintering quarter is, during our research, the Goleşti Reservoir, with impressive concentrations of waterbirds. Mention should be made of five characteristic species (eudominant and dominant present in the area of the reservoirs in the hiemal season: Anas platyrhynchos, Aythya ferina, Fulica atra, Aythya fuligula and Larus ridibundus. The high number of subrecedent species (102 emphasizes the great fluctuation of bird species in the area as a result of the fact that these reservoirs are on the course of some European migration routes and ensure favourable conditions (halting, sheltering and feeding

  8. Valley evolution by meandering rivers

    Science.gov (United States)

    Limaye, Ajay Brian Sanjay

    Fluvial systems form landscapes and sedimentary deposits with a rich hierarchy of structures that extend from grain- to valley scale. Large-scale pattern formation in fluvial systems is commonly attributed to forcing by external factors, including climate change, tectonic uplift, and sea-level change. Yet over geologic timescales, rivers may also develop large-scale erosional and depositional patterns that do not bear on environmental history. This dissertation uses a combination of numerical modeling and topographic analysis to identify and quantify patterns in river valleys that form as a consequence of river meandering alone, under constant external forcing. Chapter 2 identifies a numerical artifact in existing, grid-based models that represent the co-evolution of river channel migration and bank strength over geologic timescales. A new, vector-based technique for bank-material tracking is shown to improve predictions for the evolution of meander belts, floodplains, sedimentary deposits formed by aggrading channels, and bedrock river valleys, particularly when spatial contrasts in bank strength are strong. Chapters 3 and 4 apply this numerical technique to establishing valley topography formed by a vertically incising, meandering river subject to constant external forcing---which should serve as the null hypothesis for valley evolution. In Chapter 3, this scenario is shown to explain a variety of common bedrock river valley types and smaller-scale features within them---including entrenched channels, long-wavelength, arcuate scars in valley walls, and bedrock-cored river terraces. Chapter 4 describes the age and geometric statistics of river terraces formed by meandering with constant external forcing, and compares them to terraces in natural river valleys. The frequency of intrinsic terrace formation by meandering is shown to reflect a characteristic relief-generation timescale, and terrace length is identified as a key criterion for distinguishing these

  9. River-tide dynamics: Exploration of nonstationary and nonlinear tidal behavior in the Yangtze River estuary

    Science.gov (United States)

    Guo, Leicheng; van der Wegen, Mick; Jay, David A.; Matte, Pascal; Wang, Zheng Bing; Roelvink, Dano; He, Qing

    2015-05-01

    River-tide dynamics remain poorly understood, in part because conventional harmonic analysis (HA) does not cope effectively with nonstationary signals. To explore nonstationary behavior of river tides and the modulation effects of river discharge, this work analyzes tidal signals in the Yangtze River estuary using both HA in a nonstationary mode and continuous wavelet transforms (CWT). The Yangtze is an excellent natural laboratory to analyze river tides because of its high and variable flow, its length, and the fact that there are do dams or reflecting barriers within the tidal part of the system. Analysis of tidal frequencies by CWT and analysis of subtidal water level and tidal ranges reveal a broad range of subtidal variations over fortnightly, monthly, semiannual, and annual frequencies driven by subtidal variations in friction and by variable river discharges. We employ HA in a nonstationary mode (NSHA) by segregating data within defined flow ranges into separate analyses. NSHA quantifies the decay of the principal tides and the modulation of M4 tide with increasing river discharges. M4 amplitudes decrease far upriver (landward portion of the estuary) and conversely increase close to the ocean as river discharge increases. The fortnightly frequencies reach an amplitude maximum upriver of that for over tide frequencies, due to the longer wavelength of the fortnightly constituents. These methods and findings should be applicable to large tidal rivers globally and have broad implications regarding management of navigation channels and ecosystems in tidal rivers.

  10. Trace Elements in River Waters

    Science.gov (United States)

    Gaillardet, J.; Viers, J.; Dupré, B.

    2003-12-01

    Trace elements are characterized by concentrations lower than 1 mg L-1 in natural waters. This means that trace elements are not considered when "total dissolved solids" are calculated in rivers, lakes, or groundwaters, because their combined mass is not significant compared to the sum of Na+, K+, Ca2+, Mg2+, H4SiO4, HCO3-, CO32-, SO42-, Cl-, and NO3-. Therefore, most of the elements, except about ten of them, occur at trace levels in natural waters. Being trace elements in natural waters does not necessarily qualify them as trace elements in rocks. For example, aluminum, iron, and titanium are major elements in rocks, but they occur as trace elements in waters, due to their low mobility at the Earth's surface. Conversely, trace elements in rocks such as chlorine and carbon are major elements in waters.The geochemistry of trace elements in river waters, like that of groundwater and seawater, is receiving increasing attention. This growing interest is clearly triggered by the technical advances made in the determination of concentrations at lower levels in water. In particular, the development of inductively coupled plasma mass spectrometry (ICP-MS) has considerably improved our knowledge of trace-element levels in waters since the early 1990s. ICP-MS provides the capability of determining trace elements having isotopes of interest for geochemical dating or tracing, even where their dissolved concentrations are extremely low.The determination of trace elements in natural waters is motivated by a number of issues. Although rare, trace elements in natural systems can play a major role in hydrosystems. This is particularly evident for toxic elements such as aluminum, whose concentrations are related to the abundance of fish in rivers. Many trace elements have been exploited from natural accumulation sites and used over thousands of years by human activities. Trace elements are therefore highly sensitive indexes of human impact from local to global scale. Pollution

  11. Development of Conceptual Designs for the Prevention of Ice Formation in the Proposed Maple River Aqueduct

    Science.gov (United States)

    2014-09-18

    34 5 HEC - RAS Model...chart ....................................................... 35 20. HEC - RAS geometry at the Maple River Aqueduct...Geographic Information Systems HEC - RAS Hydrologic Engineering Center River Analysis System IDNR Illinois Department of Natural Resources NAVD88 North

  12. Radon in water of Shu river valley

    Directory of Open Access Journals (Sweden)

    Yelena Kuyanova

    2012-03-01

    Full Text Available The values of radon and its daughter products in water of Shu River valley have been received, using liquid scintillation spectrometry. The radon concentration naturally increases in investigated water samples downstream the Shu River, reaching the maximum value in the Tashutkolsky basin. The radon and its daughter products in a human body of 15 % are in soft tissues have been calculated by a mathematical modeling method. The annual dose from radon and its daughter products calculated by a mathematical modeling method received by the residents living in Shu river valley is 0,03 mSv/year.

  13. 33 CFR 162.90 - White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false White River, Arkansas Post Canal... White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River, Ark... apply to: (1) Waterways. White River between Mississippi River and Arkansas Post Canal, Ark.; Arkansas...

  14. Advances in understanding river-groundwater interactions

    Science.gov (United States)

    Brunner, Philip; Therrien, René; Renard, Philippe; Simmons, Craig T.; Franssen, Harrie-Jan Hendricks

    2017-09-01

    River-groundwater interactions are at the core of a wide range of major contemporary challenges, including the provision of high-quality drinking water in sufficient quantities, the loss of biodiversity in river ecosystems, or the management of environmental flow regimes. This paper reviews state of the art approaches in characterizing and modeling river and groundwater interactions. Our review covers a wide range of approaches, including remote sensing to characterize the streambed, emerging methods to measure exchange fluxes between rivers and groundwater, and developments in several disciplines relevant to the river-groundwater interface. We discuss approaches for automated calibration, and real-time modeling, which improve the simulation and understanding of river-groundwater interactions. Although the integration of these various approaches and disciplines is advancing, major research gaps remain to be filled to allow more complete and quantitative integration across disciplines. New possibilities for generating realistic distributions of streambed properties, in combination with more data and novel data types, have great potential to improve our understanding and predictive capabilities for river-groundwater systems, especially in combination with the integrated simulation of the river and groundwater flow as well as calibration methods. Understanding the implications of different data types and resolution, the development of highly instrumented field sites, ongoing model development, and the ultimate integration of models and data are important future research areas. These developments are required to expand our current understanding to do justice to the complexity of natural systems.

  15. River Ehen and tributaries SSSI

    OpenAIRE

    1998-01-01

    This is the River Ehen and Tributaries SSSI consultation Protocol for the Environment Agency with English Nature, produced in 1998. The Protocol is intended to provide for consistency of approach, to clarify responsibilities and help to streamline the statutory consultation and consenting procedures in which both organisations are involved. It provides guiding principles on the approach to management issues. Based on the operations likely to damage the special interest (OLDSI) which forms par...

  16. Investigations into the Early Life History of Naturally Produced Spring Chinook Salmon in the Grande Ronde River Basin : Fish Research Project Oregon : Annual Progress Report Project Period 1 September 1998 to 31 August 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Jonasson, Brian C.

    2000-01-01

    We determined migration timing and abundance of juvenile spring chinook salmon from three populations in the Grande Ronde River basin. We estimated 13,180 juvenile chinook salmon left upper rearing areas of the Grande Ronde River from July 1998 to June 1999; approximately 0.2% of the migrants left in summer, 18% in fall and 82% in spring. We estimated 15,949 juvenile chinook salmon left upper rearing areas of Catherine Creek from July 1998 to June 1999; approximately 0.2% of the migrants left in summer, 57% in fall, 2% in winter, and 41% in spring. We estimated 14,537 juvenile chinook salmon left the Grande Ronde Valley, located below the upper rearing areas in Catherine Creek and the Grande Ronde River, from October 1998 to June 1999; approximately 99% of the migrants left in spring. We estimated 31,113 juvenile chinook salmon left upper rearing areas of the Lostine River from July 1998 to June 1999; approximately 4% of the migrants left in summer, 57% in fall, 3% in winter, and 36% in spring. We estimated 42,705 juvenile spring chinook salmon left the Wallowa Valley, located below the mouth of the Lostine River, from August 1998 to June 1999; approximately 46% of the migrants left in fall, 6% in winter, and 47% in spring. Juvenile chinook salmon PIT-tagged on the upper Grande Ronde River were detected at Lower Granite Dam from 31 March to 20 June 1999, with a median passage date of 5 May. PIT-tagged salmon from Catherine Creek were detected at Lower Granite Dam from 19 April to 9 July 1999, with a median passage date of 24 May. PIT-tagged salmon from the Lostine River were detected at Lower Granite Dam from 31 March through 8 July 1999, with a median passage date of 4 May. Juveniles tagged as they left the upper rearing areas of the Grande Ronde River in fall and that overwintered in areas downstream were detected in the hydrosystem at a higher rate than fish tagged during winter in the upper rearing areas, indicating a higher overwinter survival in the

  17. The Ryan/Harley site: Sedimentology of an inundated Paleoindian site in north Florida

    Science.gov (United States)

    Balsillie, J.H.; Means, G.H.; Dunbar, J.S.

    2006-01-01

    The Ryan/Harley site (Florida Master Site File Number: 8Je-1004) is a Middle Paleoindian habitation site containing Suwannee points. Based on stratigraphic correlation and diagnostic artifact seriation, Suwannee-age sites have been relatively dated from ??? 10,900 14C yr B.P to ??? 10,500 14C yr B.P. Clovis-like traits on the Suwannee points and other stone tools from the Ryan/Harley site suggest it dates to the earlier end of the Suwannee timeframe. The currently inundated site is partially buried beneath a sediment column located in a swamp forest and partially exposed in a side channel section of the Wacissa River, Jefferson County, Florida. Research done prior to this analysis determined that the artifact assemblage appeared to be unsorted and was contained in a midden-like unit. Our purpose here is to assess the issue of site integrity further. Unconsolidated sediment samples collected from the artifact-bearing horizon and from horizons immediately above and below the artifact horizon were analyzed using granulometric techniques. Arithmetic probability plots of the grain-size distributions show that the sediments were transported and deposited by fluvial processes. Thus, the Suwannee points and associated artifacts, and faunal remains appear to have accumulated during a time of subaerial exposure perhaps after a regional water-table decline, and have remained largely or essentially intact, with little or no postdepositional reworking. The artifacts and faunal remains recovered from the artifact-bearing horizon at Ryan/Harley are distributed randomly, showing no sign of sorting. In the fossil suite, two articulated white-tailed deer (Odocoileus virginianus) vertebra were recovered in situ. The unsorted nature of artifacts and articulated faunal remains that are contained within the fluvially deposited sediments suggests the Suwannee point level of the Ryan/Harley site has remained undisturbed since original deposition. ?? 2006 Wiley Periodicals, Inc.

  18. Photochemical production of superoxide and hydrogen peroxide from natural organic matter

    Science.gov (United States)

    Garg, Shikha; Rose, Andrew L.; Waite, T. David

    2011-08-01

    Irradiation of Suwannee River fulvic acid (SRFA) at pH 8.1 with simulated sunlight resulted in production of nanomolar concentrations of superoxide and hydrogen peroxide. SRFA contains a redox-active chromophore which reduced oxygen to yield superoxide upon photoexcitation. Hydrogen peroxide was generated exclusively via uncatalysed disproportionation of superoxide produced in this way. Superoxide decayed through both uncatalysed disproportionation and an oxidative pathway that did not result in hydrogen peroxide production, whereas hydrogen peroxide did not undergo further reaction to any discernible extent over the one-hour duration of irradiation. Singlet oxygen did not contribute substantially to production of superoxide or hydrogen peroxide but was found to play a critical role in controlling the mechanism and associated rate of superoxide decay in the irradiated solution. A kinetic model based on these observations is presented which provides an excellent description of the experimental results and is also consistent with observations from a wide range of other studies in which various aspects of SRFA redox chemistry and photochemistry have been investigated.

  19. Geochemical characteristics of Heavy metals of river sediment from the main rivers at Texas, USA.

    Science.gov (United States)

    Matsumoto, I.; Hoffman, D.; MacAlister, J.; Ishiga, H.

    2008-12-01

    Trinity River is one of the biggest rivers which flows through Dallas and Fort Worth two big cities of USA and are highly populated. Trinity river drains into the Gulf of Mexico. Sediment samples collected from various points along the upper and lower streams were subjected to content analysis and elution analysis (using liquate (flow) out test) on the heavy metals like Cd, CN, Pb, Cr, As, Hg, Ni, Zn and Cu from the river sediment for the purpose of environment assessment. A total of 22 sample points were identified from upper stream to lower stream and samples were collected such that almost the whole stream length of Trinity River is covered. Results show that heavy metal content through out the river stream is below the recommended limits posing no immediate environmental threat. However, the experimental results show clear impact of human population in bigger cities on heavy metal concentrations in the river sediments as compared to smaller cities with low human population. It could be seen from the analysis that all the heavy metals show relatively high content and high elution value in Dallas and Fort Worth. As we move away from the big cities, the value of content and elution of sediment decreased by natural dilution effect by the river. And we also present the data of the Colorado and San Antonio rivers.

  20. Using Radon-222 as a Naturally Occurring Tracer to investigate the streamflow-groundwater interactions in a typical Mediterranean fluvial-karst landscape: the interdisciplinary case study of the Bussento river (Campania region, Southern Italy).

    Science.gov (United States)

    Cuomo, Albina; Guida, Michele; Guida, Domenico; Villani, Paolo; Guadagnuolo, Davide; Longobardi, Antonia; Siervo, Vincenzo

    2010-05-01

    Karst aquifers provide 25% of the overall drinking water resources to the world's population and sustain aquatic life in most fluvial systems, providing several ecological services to human beings, although, because of their complex links between surface and groundwater, turn out to be very vulnerable to contamination and pollution. This paper describes the preliminary findings from Radon-222 activity concentration measurement data collected in streamflow and instream springs during monthly field campaigns, performed from September 2007 to December 2008, in a typical Mediterranean karst river: the Bussento river (Campania region, Southern Italy). The general aim is to investigate the complex interactions and exchanges between streamflow and groundwater, at scales that are imperceptible to standard hydrological and hydraulic analyses. In fact, the study area is located inside the Cilento and Vallo di Diano National Park and, therefore, the management of its relevant water resources requires not only groundwater protection for domestic drinking use, but also riverine wildlife preservation and coastal water quality maintenance. As a support for hydro-geomorphological and hydrological modelling for planning tasks, in application of the European Water Framework Directive (EWFD), a Bussento River Monitoring System (BRMS) has been built, at basin, segment and reach scale. Experimental data about 222Rn concentrations, in addition to physical-chemical and streamflow rate, have been acquired and managed from BRMS selected stations, sampling the streamflow and inflow spring waters by means of the Radon-in-Air analyzer, RAD7, together with the Radon-in-water accessories, Radon Water Probe and RAD7H2O (DURRIDGE Co. Inc.), for continuous and batch sampling measurements, respectively. During preliminary surveys, appropriate sampling procedures and measurement protocols have been tested, taking into account the different local hydrogeological and hydrological situations occurring

  1. Laboratory rivers: Lacey's law, threshold theory, and channel stability

    OpenAIRE

    Métivier, F.; Lajeunesse, E.; Devauchelle, O.

    2017-01-01

    International audience; More than a century of experiments have demonstrated that many features of natural rivers can be reproduced in the laboratory. Here, we revisit some of these experiments to cast their results into the framework of the threshold-channel theory developed by Glover and Florey (1951). In all the experiments we analyze, the typical size of the channel conforms to this theory, regardless of the river's planform (single-thread or braiding). In that respect, laboratory rivers ...

  2. Investigations into the Early Life History of Naturally Produced Spring Chinook Salmon and Summer Steelhead in the Grande Ronde River Subbasin, Annual Report 2008 : Project Period 1 February 2008 to 31 January 2009.

    Energy Technology Data Exchange (ETDEWEB)

    Yanke, Jeffrey A.; Alfonse, Brian M.; Bratcher, Kyle W. [Oregon Department of Fish and Wildlife

    2009-07-31

    This study was designed to document and describe the status and life history strategies of spring Chinook salmon and summer steelhead in the Grande Ronde River Subbasin. We determined migration timing, abundance, and life-stage survival rates for juvenile spring Chinook salmon Oncorhynchus tshawytscha and summer steelhead O. mykiss in four streams during migratory year 2008 from 1 July 2007 through 30 June 2008. As observed in previous years of this study, spring Chinook salmon and steelhead exhibited fall and spring movements out of natal rearing areas, but did not begin their smolt migration through the Snake and lower Columbia River hydrosystem until spring. In this report we provide estimates of migrant abundance and migration timing for each study stream, and their survival and timing to Lower Granite Dam. We also document aquatic habitat conditions using water temperature and stream flow in four study streams in the subbasin.

  3. The Columbia River System : the Inside Story.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1991-09-01

    The Columbia Ricer is one of the greatest natural resources in the western United States. The river and its tributaries touch the lives of nearly every resident of the Northwest-from providing the world-famous Pacific salmon to supplying the clean natural fuel for over 75 percent of the region's electrical generation. Since early in the century, public and private agencies have labored to capture the benefits of this dynamic river. Today, dozens of major water resource projects throughout the region are fed by the waters of the Columbia Basin river system. And through cooperative efforts, the floods that periodically threaten developments near the river can be controlled. This publication presents a detailed explanation of the planning and operation of the multiple-use dams and reservoirs of the Columbia River system. It describes the river system, those who operate and use it, the agreements and policies that guide system operation, and annual planning for multiple-use operation.

  4. River pollution control

    National Research Council Canada - National Science Library

    Stiff, M.J

    1980-01-01

    Readers will gain an insight into the problems of other countries, particularly those with trans-frontier rivers, the measures adopted to improve river quality, and how the World Health Organization...

  5. Allegheny County Major Rivers

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  6. Illinois River NWFR HMP

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Illinois River National Wildlife and Fish Refuges Complex stretches along 124 miles of the Illinois River in west central Illinois. The Complex includes three...

  7. Iowa's Sovereign Meandered Rivers

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This data set depicts Iowa's Meandered Rivers. These rivers are deemed sovereign land & therefore require any person wishing to conduct construction activities...

  8. Suitability Evaluation on River Bank Filtration of the Second Songhua River, China

    Science.gov (United States)

    Wang, Lixue; Ye, Xueyan; Du, Xinqiang

    2016-04-01

    The Second Songhua River is the biggest river with the most economic value in Jilin Province, China. In recent years, with the rapid development of economy, water resources and water environment problem is getting prominent, including surface water pollution and over exploitation of groundwater resources, etc. By means of bank filtration, the Second Songhua River basin might realize the combined utilization of regional groundwater and surface water, and thus has important significance for the guarantee of water demand for industrial and agricultural production planning in the basin. The following steps were adopted to evaluate the suitability of bank filtration nearby the Scond Songhua River : Firstly, in order to focus on the most possible area, the evaluation area was divided based on the aspects of natural geographical conditions and hydraulic connection extent between river water and groundwater. Second, the main suitability indexes including water quantity, water quality, interaction intensity between surface water and groundwater, and the exploitation condition of groundwater resource, and nine sub-indexes including hydraulic conductivity, aquifer thickness, river runoff, the status of groundwater quality, the status of surface water quality, groundwater hydraulic gradient, possible influence zone width of surface water under the condition of groundwater exploitation, permeability of riverbed layer and groundwater depth were proposed to establish an evaluation index system for the suitability of river bank filtration. Thirdly, Combined with the natural geography, geology and hydrogeology conditions of the Second Songhua River basin, the ArcGIS technology is used to complete the evaluation of the various indicators. According to the weighted sum of each index, the suitability of river bank filtration in the study area is divided into five grades. The evaluation index system and evaluation method established in this article are applicable to the Second Songhua

  9. Natural Childbirth

    Science.gov (United States)

    ... cold, ice Cold, Ice, and Snow Safety Natural Childbirth KidsHealth > For Parents > Natural Childbirth Print A A ... the pain, extremely empowering and rewarding. About Natural Childbirth Natural childbirth is a "low-tech" way of ...

  10. local government headquarters and spatial interaction within rivers

    African Journals Online (AJOL)

    user

    Department of Geography and Environmental Studies,. Rivers State University Of Education, Port Harcourt. Email nalubagoddy@yahoo.com. ABSTRACT. This paper examines local the nature of the relationship between the local government headquarters and rural hinterland settlements in Rivers South East Senatorial ...

  11. Measuring River Pollution

    Science.gov (United States)

    Ayyavoo, Gabriel

    2004-01-01

    The Don River watershed is located within Canada's most highly urbanized area--metropolitan Toronto. Many residential and commercial uses, including alterations to the river's course with bridges, have had a significant impact on the Don's fauna and flora. Pollutants have degraded the river's water quality, a situation exacerbated by the…

  12. RIVER-RAD: A computer code for simulating the transport of radionuclides in rivers

    Energy Technology Data Exchange (ETDEWEB)

    Hetrick, D.M.; McDowell-Boyer, L.M.; Sjoreen, A.L.; Thorne, D.J.; Patterson, M.R.

    1992-11-01

    A screening-level model, RIVER-RAD, has been developed to assess the potential fate of radionuclides released to rivers. The model is simplified in nature and is intended to provide guidance in determining the potential importance of the surface water pathway, relevant transport mechanisms, and key radionuclides in estimating radiological dose to man. The purpose of this report is to provide a description of the model and a user's manual for the FORTRAN computer code.

  13. 78 FR 17752 - Tongue River Railroad Company, Inc.-Rail Construction and Operation-In Custer, Powder River and...

    Science.gov (United States)

    2013-03-22

    ... Custer, Powder River and Rosebud Counties, Mont. AGENCY: Lead: Surface Transportation Board; Cooperating..., Montana Department of Natural Resources and Conservation (acting as lead agency for other Montana State... coal from proposed mine sites in Rosebud and Powder River Counties, Montana. Because the construction...

  14. Rivers and ports in transport history of Cameroon, 1916-1961 | Nkwi ...

    African Journals Online (AJOL)

    In direct contrast to Europe, Asia and North America, Africa has very few navigable rivers. This paper focuses on the preponderant role played by water transport in the form of rivers and ports during the colonial period. Although not blessed with much navigable rivers and natural deep ports, the Colonial administration as ...

  15. Groundwater flow modelling in the upper Anga'a river watershed ...

    African Journals Online (AJOL)

    ISHIOMA

    Lateral inflows and outflows were simulated with constant head. The Anga'a river heads and the Lake levels were simulated using a river package. Natural recharge due to rainfall formed the main input to the aquifer system and the output was made of abstraction from pumping wells, base flow to Anga'a River, lake, springs ...

  16. Investigations into the Early Life History of Naturally Produced Spring Chinook Salmon and Summer Steelhead in the Grande Ronde River Basin : Annual Report 2000 : Project Period 1 October 1999 to 30 November 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Monzyk, Fred R.

    2002-06-01

    The authors determined migration timing and abundance of juvenile spring chinook salmon Oncorhynchus tshawytscha and juvenile steelhead/rainbow trout O. mykiss from three populations in the Grande Ronde River basin. Based on migration timing and abundance, two distinct life-history strategies of juvenile spring chinook and O.mykiss could be distinguished. An early migrant group left upper rearing areas from July through January with a peak in the fall. A late migrant group descended from upper rearing areas from February through June with a peak in the spring.

  17. River basin administration

    Science.gov (United States)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  18. Hydraulic Geometry Analysis of the Lower Mississippi River

    National Research Council Canada - National Science Library

    Soar, Philip J; Thorne, Colin R; Harmar, Oliver P

    2005-01-01

    The hydraulic geometry of the Lower Mississippi River is primarily the product of the action of natural flows acting on the floodplain materials over centuries and millennia to form an alluvial forming a channel...

  19. Assessing the Global Extent of Rivers Observable by SWOT

    Science.gov (United States)

    Pavelsky, T.; Durand, M. T.; Andreadis, K.; Beighley, E.; Allen, G. H.; Miller, Z.

    2013-12-01

    would be measured. The improved observation capacity available if 50 m wide rivers are measured is important because natural and human processes often impact streamflow at scales smaller than 50,000 km2. Regardless, though, SWOT could likely match (in well-gauged areas at 100 m) or exceed (in less gauged areas) the spatial extent of the GRDC gauge network for basins larger than ~10,000 km2.

  20. Application of stable isotopes (δ³⁴S-SO₄, δ¹⁸O-SO₄, δ¹⁵N-NO ₃, δ¹⁸O-NO ₃) to determine natural background and contamination sources in the Guadalhorce River Basin (southern Spain).

    Science.gov (United States)

    Urresti-Estala, Begoña; Vadillo-Pérez, Iñaki; Jiménez-Gavilán, Pablo; Soler, Albert; Sánchez-García, Damián; Carrasco-Cantos, Francisco

    2015-02-15

    The integrated use of isotopes (δ(34)S-SO4, δ(18)O-SO4, δ(15)N-NO3, δ(18)O-NO3), taking into account existing hydrogeological knowledge of the study area (mainly hydrochemical), was applied in the Guadalhorce River Basin (southern Spain) to characterise SO4(2-) and NO3(-) sources, and to quantify natural background levels (NBLs) in groundwater bodies. According to Water Framework Directive 2000/60/EC and, more recently, Groundwater Directive 2006/118/EC, it is important to determine NBLs, as their correct assessment is the first, essential step to characterising groundwater bodies, establishing threshold values, assessing chemical status and identifying trends in pollutant concentrations. In many cases, NBLs are high for some parameters and types of groundwater, making it difficult to distinguish clearly between factors of natural or human origin. The main advantages of using stable isotopes in a complex area like the Guadalhorce River Basin that exhibits widely varying hydrogeological and hydrochemical conditions and longstanding anthropogenic influences (mainly agriculture, but also many others) is accurate determination of pollution sources and precise quantification of NBLs. Since chemical analyses only provides the concentration of pollutants in water and not the source, three isotopic sampling campaigns for sulphates (δ(34)S-SO4, δ(18)O-SO4) were carried out, in 2006, 2007 and 2012, and another one was conducted for nitrates (δ(15)N-NO3, δ(18)O-NO3), in 2009, in groundwater bodies in order to trace the origins of each pollutant. The present study identified different pollution sources of dissolved NO3(-) in groundwater using an isotopic composition and quantified the percentage of natural (lithology, chemical and biological processes) and anthropogenic (fertilisers, manure and sewage) SO4(2-) and matched a concentration associated with the percentage in order to determine the NBLs in the basin. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Polimorfismo molecular em Lonchocarpus cultratus (Fabaceae de áreas ripárias de reflorestamento natural no alto rio Paraná, Brasil - DOI: 10.4025/actascibiolsci.v26i3.1596 Molecular polymorphism in Lonchocarpus cultratus (Fabaceae from riparian areas of natural reforesting in Upper Paraná River, Brazil - DOI: 10.4025/actascibiolsci.v26i3.1596

    Directory of Open Access Journals (Sweden)

    Léia Carolina Lucio

    2004-04-01

    Full Text Available No Sul e Sudeste do Brasil, Lonchocarpus cultratus (Vell. A.M.G. Azevedo e H.C. Lima é uma espécie arbórea importante para o reflorestamento natural, incluindo áreas ripárias. Em florestas regeneradas, diferentemente de florestas não perturbadas, esta espécie tem sido observada como agregados de plantas semelhantes entre si, ao ponto de ter sido formulada a hipótese de serem clones. Em um estudo prévio, brotamento de raízes foi observado em L. cultratus, em uma floresta afetada pelo fogo. No presente estudo, análises de polimorfismo de RAPD revelaram alta diversidade genética entre as plantas de agregados de L. cultratus, em uma floresta ripária afetada pelo fogo, no alto rio Paraná. Os dados permitem sugerir que reprodução sexual tem sido a usual estratégia reprodutiva de colonização de L. cultratus, nesta área de reflorestamento naturalLonchocarpus cultratus (Vell. A.M.G. Azevedo and H.C. Lima is an important plant species in areas of natural reforesting in South and Southeastern Brazil, including riparian areas. This arboreous species seems to reproduce by seeds in undisturbed forests. In regenerating forests, however, L. cultratus has been observed mostly as patches of aggregates, consisting of highly similar plants, resembling clones. Sprouting from root buds had been previously observed in L. cultratus in a forest affected by fire. In the present study, RAPD polymorphism revealed high genetic diversity among plants from L. cultratus aggregates in a natural restoring riparian forest affected by fires, in the Upper Paraná River, Brazil. These data allow the suggestion that sexual reproduction has been the L. cultratus usual reproductive strategy to colonize the reforesting riparian area

  2. Savannah River Technology Center. Monthly report

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This document contains information about the research programs being conducted at the Savannah River Plant. Topics of discussion include: thermal cycling absorption process, development of new alloys, ion exchange, oxalate precipitation, calcination, environmental research, remedial action, ecological risk assessments, chemical analysis of salt cakes, natural phenomena hazards assessment, and sampling of soils and groundwater.

  3. Tidal controls on river delta morphology

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Wang, Z. B.; Vermeulen, B.; Huismans, Y.; Kästner, K.

    2017-01-01

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world's largest deltas intensifies. Harbour development, construction of flood defences, sand mining and

  4. Towards Biological Restoration of Tehran Megalopolis River Valleys- Case Study: Farahzad River

    Science.gov (United States)

    Samadi, Nafishe; Oveis Torabi, Seyed; Akhani, Hossein

    2017-04-01

    Towards biological restoration of Tehran megalopolis river-valleys: case study Farahzad river 1Nafiseh Samadi, 2OveisTorabi, 3Hossein Akhani 1Mahsab Shargh Company, Tehran ,Iran, nafiseh19@gmail.com 2 Mahsab Shargh Company, Tehran ,Iran, weg@tna-co.com 3Department of Plant Sciences, Halophytes and C4 Research Laboratory, School of Biology, College of Sciences, University of Tehran, PO Box 14155-6455, Tehran, Iran, akhani@khayam.ut.ac.ir Tehran is located in northcentral parts of Iran on the alluvium of southern Alborz Mountains. Seven rivers originated from the highlands of N Tehran run inside and around the city. Many of these river valleys have been deformed by a variety of urban utilizations such as garden, building, canal, park, autobahn etc. Tehran with more than eight million populations suffered from adverse environmental conditions such as pollution and scarcity of natural habitats for recreational activities. Ecological restoration of altered river valleys of Tehran is one of the priorities of Tehran municipality started as a pilot project in Farahzad river. Intensive disturbance, conversion into various urban utilization, illegal building construction, waste water release into the river, garbage accumulation, artificial park constructions and domination of invasive species have largely altered the river. Parts of the river located in Pardisan Nature Park was studied before its complete deformation into a modern park. The riparian vegetation consisted of Tamarix ramosissima and Salix acmophylla shrubs with large number of aquatic and palustric plants. The norther parts of the river still contain semi-natural vegetation which change into patchy and intensive degraded habitats towards its southern parts. In northern parts of valley there are old gardens of Morus alba and Juglans regia, and planted trees such as Plataneus oreientalis and Acer negundo. Salix acmophylla, Fraxinus excelsior and Celtis caucasica are native species growing on river margin or

  5. Tucannon River Temperature Study, Prepared for : Watershed Resource Inventory Area (WRIA) 35.

    Energy Technology Data Exchange (ETDEWEB)

    HDR Engineering.

    2006-06-30

    This report presents the results of a temperature analysis of the Tucannon River completed for the WRIA 35 Planning Unit. The Tucannon River is located in southeastern Washington and flows approximately 100 kilometers (km) (62 miles) from the Blue Mountains to the Snake River. High water temperature in the Tucannon River has been identified as a limiting factor for salmonid fish habitat (Columbia Conservation District, 2004). Several segments of the Tucannon River are included on Washington State Department of Ecology (Ecology) 303(d) list of impaired waterbodies due to temperature. Ecology is currently conducting scoping for a temperature Total Maximum Daily Load (TMDL) study of the Tucannon River. The WRIA 35 Planning Unit retained HDR Engineering to evaluate water temperature in the Tucannon River. The project objectives are: (1) Review recent and historic data and studies to characterize temperature conditions in the river; (2) Perform field studies and analyses to identify and quantify heating and cooling processes in the river; (3) Develop and calibrate a computer temperature model to determine the sources of heat to the Tucannon River and to predict the temperature of the river that would occur with increased natural riparian shading assuming the current river morphology; (4) Evaluate differences in river temperatures between current and improved riparian shading during the 'critical' period - low river flows and high temperatures; and (5) Determine the potential benefits of riparian shading as a mechanism to decrease river temperature.

  6. Influence of natural organic matter on transport and retention of polymer coated silver nanoparticles in porous media.

    Science.gov (United States)

    Yang, Xinyao; Lin, Shihong; Wiesner, Mark R

    2014-01-15

    Interactions between organic matter (OM) and engineered polymer coatings as they affect the retention of polyvinylpyrrolidone (PVP) polymer-coated silver nanoparticles (AgNPs) were studied. Two distinct types of OM-cysteine representing low molecular weight multivalent functional groups, and Suwannee River Humic Acid (HA) representing high molecular weight polymers, were investigated with respect to their effects on particle stability in aggregation and deposition. Aggregation of the PVP coated AgNPs (PVP-AgNPs) was enhanced by cysteine addition at high ionic strengths, which was attributed to cysteine binding to the AgNPs and replacing the otherwise steric stabilizing agent PVP. In contrast the addition of HA did not increase aggregation rates and decreased PVP-AgNP deposition to the silica porous medium, consistent with enhanced electrosteric stabilization by the HA. Although cysteine also reduced deposition in the porous medium, the mechanisms of reduced deposition appear to be enhanced electric double layer (EDL) interaction at low ionic strengths. At higher ionic strengths, aggregation was favored leading to lower deposition due to smaller diffusion coefficients and single collector efficiencies despite the reduced EDL interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Synthesis of carboxylated styrene polymer for internal calibration of Fourier transform ion cyclotron resonance mass-spectrometry of humic substances.

    Science.gov (United States)

    Zherebker, Alexander; Turkova, Alexandra V; Kostyukevich, Yury; Kononikhin, Alexey; Zaitsev, Kirill V; Popov, Igor A; Nikolaev, Eugene; Perminova, Irina V

    2017-08-01

    We report synthesis and application of the novel carboxylated styrene for internal calibration of Fourier transform ion cyclotron resonance mass-spectra of humic substances. The calibrant was synthesized in five steps from acetylsalicylic acid (aspirin) followed by spontaneous polymerization of vinyl salicylic acid. Aromatic nature of the prepared polymer enabled its simultaneous analysis in the presence of the Suwannee River fulvic acid without using dual-spray approach. The major advantage of the calibrant proposed in this study is a lack of suppression of humic substances signals and maintenance of peak intensity distribution. The appropriate calibration resulted in an increased number of unambiguous identification in Suwannee River fulvic acid. Thanks to the higher mass accuracy, it was also possible to refine attribution of the CHOS species to hydrolysable tannins as opposed to the erroneous previous assignment to the condensed tannins.

  8. Assessment of injury to river otters in Prince William Sound, Alaska, following the Exxon Valdez oil spill. Terrestrial mammal study number 3. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    Energy Technology Data Exchange (ETDEWEB)

    Faro, J.B.; Bowyer, R.T.; Testa, J.W.; Duffy, L.K.

    1994-03-01

    River otters (Lutra canadensis) were killed by direct effects of the Exxon Valdez oil spill, but the magnitude of that loss is unknown due to lack of pre-spill data. A time lag in spill effects is reflected by the reduction in species richness and diversity in the summer diets of otters in oiled areas between 1989 and 1990. Otters from oiled areas had higher haptoglobin levels in both 1990 and 1991. Male otters captured in oiled areas in 1990 had significantly lower body mass than otters from nonoiled areas. Otters from oiled areas had home ranges that were twice as large as those from a non-spill area. Differences in rates of fecal deposition between oiled and nonoiled latrine sites in 1989 suggest otters used heavily oiled areas less often. Otters avoided shorelines with shallow slopes on the oiled area, whereas they strongly preferred these slopes on nonoiled sites, suggesting that otters lost habitat as a result of the spill.

  9. Migration of radionuclides through a river system

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    Migration behavior of several atmospherically-derived radionuclides in a river watershed was studied. A main interest was in their relocation from the ground soil of the watershed to a downstream region through a river. Studied radionuclides are: {sup 137}Cs generated by weapon tests in the atmosphere; {sup 210}Pb and {sup 7}Be of naturally occurring radionuclides; {sup 137}Cs, {sup 90}Sr, {sup 239,240}Pu and {sup 241}Am released by the Chernobyl nuclear power plant accident. Dominance of the form in suspended solid in river water (particulate form) was qualified for the radionuclides in the Kuji river watershed. An importance of discharge in flooding was also confirmed. A historical budget analysis for weapon test derived {sup 137}Cs was presented for the Hi-i river watershed and its accompanied lake sediment (Lake Shinji). The work afforded a scheme of a fate of {sup 137}Cs after falling on the ground soil and on the lake surface. Several controlling factors, which can influence on the chemical form of radionuclides discharged to a river, were also investigated in the vicinity of the Chernobyl nuclear power plant. A special attention was paid on the association of the radionuclides with dissolved species in water. Preferential association of Pu and Am isotopes to a large molecular size of dissolved matrices, probably of humic substances, was suggested. (author)

  10. The Mechanics of River Avulsions on Deltas

    Science.gov (United States)

    Ganti, Vamsi; Chadwick, Austin; Hassenruck-Gudipati, Hima; Lamb, Michael

    2017-04-01

    River deltas are highly dynamic, often fan-shaped depositional systems that form when rivers drain into a standing body of water. They host over a half billion people worldwide and are currently under threat of drowning and destruction by relative sea-level rise, subsidence, and anthropogenic interference. Many river deltas develop planform fan shapes through avulsions, whereby major river channel shifts occur via "channel jumping" about a persistent spatial node, thus determining their fundamental length scale. Emerging theories suggest that the size of deltas is set by backwater hydrodynamics; however, these ideas are difficult to test on natural deltas, which evolve on centennial to millennial timescales. Here, using physical experiments coupled with observations of the dynamics of modern deltaic evolution, we show that deltas grow through successive deposition of lobes that maintain a constant size that scales with backwater hydrodynamics. The preferential avulsion node in our experiments is a consequence of multiple river floods and Froude-subcritical flows that produce persistent nonuniform flows and a peak in net channel deposition within the backwater zone of the coastal river. Moreover, because the backwater hydrodynamics are controlled by the downstream boundary condition of constant sea level, the backwater-mediated avulsion sites translate seaward in step with shoreline progradation. In contrast, experimental deltas without multiple floods produce flows with uniform velocities and delta lobes that lack a characteristic size. Results have broad applications to sustainable management of deltas and for decoding their stratigraphic record on Earth and Mars.

  11. Fish diseases in coastal rivers

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, H.

    1984-10-01

    Fish diseases have been used as pollution indicators in surface water for about 15 years. The complex interdependences between pathogens, fish, and a multitude of environmental parameters make data evaluation difficult and may lead to misinterpretations. The effects of the natural environment are found to be more important than pollutant effects. To give an example: In a number of fish species, disease rates were highest not in the strongly polluted stretch of river near Hamburg but in the estuarine region where pollutant concentrations are comparatively low but salt content fluctuations are high.

  12. Nitrosation and Nitration of Fulvic Acid, Peat and Coal with Nitric Acid

    National Research Council Canada - National Science Library

    Thorn, Kevin A; Cox, Larry G

    2016-01-01

    ...) in general, in the context of a variety of environmental and biogeochemical processes. Suwannee River NOM, Suwannee River fulvic acid, and Pahokee Peat fulvic acid were treated with 15N-labeled nitric acid at concentrations ranging from 15% to 22...

  13. Development and preliminary application of a method to assess river ecological status in the Hai River Basin, north China.

    Science.gov (United States)

    Shan, Baoqing; Ding, Yuekui; Zhao, Yu

    2016-01-01

    The river ecosystem in the Hai River Basin (HRB), an important economic region in China, is seriously degraded. With the aim of river restoration in the HRB, we developed a method to assess the river's ecological status and conducted a preliminary application of the method. The established method was a predictive model, which used macroinvertebrates as indicator organisms. The river's ecological status was determined by calculating the ratio of observed to expected values (O/E). The method included ecoregionalization according to natural factors, and the selection of reference sites based on combinations of habitat quality and macroinvertebrate community. Macroinvertebrate taxa included Insecta, Crustacea, Gastropoda, and Oligochaeta, with 39 families and 95 genera identified in the HRB. The HRB communities were dominated by pollution tolerant taxa, such as Lymnaeidae, Chironomus, Limnodrilus, Glyptotendipes, and Tubifex. The average Shannon-Wiener index was 1.40±0.5, indicating a low biodiversity. In the river length of 3.31×10(4) km, 55% of the sites were designated poor, with a bad ecological status. Among nine secondary river systems, Luan and Zi-ya had the best and worst river conditions, respectively. Only 17 reference site groups were selected for river management in the 41 ecoregions examined. This study lays the foundation for river restoration and related research in the HRB, and we anticipate further developments of this novel method. Copyright © 2015. Published by Elsevier B.V.

  14. Multi-tracer investigation of river and groundwater interactions: a case study in Nalenggele River basin, northwest China

    Science.gov (United States)

    Xu, Wei; Su, Xiaosi; Dai, Zhenxue; Yang, Fengtian; Zhu, Pucheng; Huang, Yong

    2017-11-01

    Environmental tracers (such as major ions, stable and radiogenic isotopes, and heat) monitored in natural waters provide valuable information for understanding the processes of river-groundwater interactions in arid areas. An integrated framework is presented for interpreting multi-tracer data (major ions, stable isotopes (2H, 18O), the radioactive isotope 222Rn, and heat) for delineating the river-groundwater interactions in Nalenggele River basin, northwest China. Qualitative and quantitative analyses were undertaken to estimate the bidirectional water exchange associated with small-scale interactions between groundwater and surface water. Along the river stretch, groundwater and river water exchange readily. From the high mountain zone to the alluvial fan, groundwater discharge to the river is detected by tracer methods and end-member mixing models, but the river has also been identified as a losing river using discharge measurements, i.e. discharge is bidirectional. On the delta-front of the alluvial fan and in the alluvial plain, in the downstream area, the characteristics of total dissolved solids values, 222Rn concentrations and δ18O values in the surface water, and patterns derived from a heat-tracing method, indicate that groundwater discharges into the river. With the environmental tracers, the processes of river-groundwater interaction have been identified in detail for better understanding of overall hydrogeological processes and of the impacts on water allocation policies.

  15. Application of stable isotopes (δ{sup 34}S-SO{sub 4}, δ{sup 18}O-SO{sub 4,} δ{sup 15}N-NO{sub 3}, δ{sup 18}O-NO{sub 3}) to determine natural background and contamination sources in the Guadalhorce River Basin (southern Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Urresti-Estala, Begoña, E-mail: b.urresti@uma.es [Universidad de Málaga, Facultad de Ciencias, Grupo de Geodinámica Externa, Campus de Teatinos s/n, 29071 Málaga (Spain); Vadillo-Pérez, Iñaki; Jiménez-Gavilán, Pablo [Universidad de Málaga, Facultad de Ciencias, Grupo de Geodinámica Externa, Campus de Teatinos s/n, 29071 Málaga (Spain); Soler, Albert [Grup de Mineralogia Aplicada i Medi Ambient, Fac. Geologia, Universitat de Barcelona, Barcelona (Spain); Sánchez-García, Damián; Carrasco-Cantos, Francisco [Universidad de Málaga, Facultad de Ciencias, Grupo de Geodinámica Externa, Campus de Teatinos s/n, 29071 Málaga (Spain)

    2015-02-15

    The integrated use of isotopes (δ{sup 34}S-SO{sub 4}, δ{sup 18}O-SO{sub 4,} δ{sup 15}N-NO{sub 3}, δ{sup 18}O-NO{sub 3}), taking into account existing hydrogeological knowledge of the study area (mainly hydrochemical), was applied in the Guadalhorce River Basin (southern Spain) to characterise SO{sub 4}{sup 2−} and NO{sub 3}{sup −} sources, and to quantify natural background levels (NBLs) in groundwater bodies. According to Water Framework Directive 2000/60/EC and, more recently, Groundwater Directive 2006/118/EC, it is important to determine NBLs, as their correct assessment is the first, essential step to characterising groundwater bodies, establishing threshold values, assessing chemical status and identifying trends in pollutant concentrations. In many cases, NBLs are high for some parameters and types of groundwater, making it difficult to distinguish clearly between factors of natural or human origin. The main advantages of using stable isotopes in a complex area like the Guadalhorce River Basin that exhibits widely varying hydrogeological and hydrochemical conditions and longstanding anthropogenic influences (mainly agriculture, but also many others) is accurate determination of pollution sources and precise quantification of NBLs. Since chemical analyses only provides the concentration of pollutants in water and not the source, three isotopic sampling campaigns for sulphates (δ{sup 34}S-SO{sub 4}, δ{sup 18}O-SO{sub 4}) were carried out, in 2006, 2007 and 2012, and another one was conducted for nitrates (δ{sup 15}N-NO{sub 3}, δ{sup 18}O-NO{sub 3}), in 2009, in groundwater bodies in order to trace the origins of each pollutant. The present study identified different pollution sources of dissolved NO{sub 3}{sup −} in groundwater using an isotopic composition and quantified the percentage of natural (lithology, chemical and biological processes) and anthropogenic (fertilisers, manure and sewage) SO{sub 4}{sup 2−} and matched a concentration

  16. Mathematics in Nature Modeling Patterns in the Natural World

    CERN Document Server

    Adam, John A

    2011-01-01

    From rainbows, river meanders, and shadows to spider webs, honeycombs, and the markings on animal coats, the visible world is full of patterns that can be described mathematically. Examining such readily observable phenomena, this book introduces readers to the beauty of nature as revealed by mathematics and the beauty of mathematics as revealed in nature.Generously illustrated, written in an informal style, and replete with examples from everyday life, Mathematics in Nature is an excellent and undaunting introduction to the ideas and methods of mathematical modeling. It illustrates how mathem

  17. Evolution of river dolphins.

    OpenAIRE

    Hamilton, H.; Caballero, S.; Collins, A. G.; Brownell, R. L.

    2001-01-01

    The world's river dolphins (Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeog...

  18. Down to the River

    DEFF Research Database (Denmark)

    Wessels, Josepha Ivanka

    2015-01-01

    Currently there is no coherent or sustainable water cooperation among the five states—Israel, Jordan, Lebanon, Palestinian territories and Syria—that share the Jordan River. Why do people not cooperate on sustainable river basin management, even if it seems the most rational course from...... to illustrate hydropolitics in praxis, because the political future of this particular area in many respects affects the sustainable future of the Jordan River Basin and the entire Levant....

  19. Hydrochemical regime and water quality of rivers and reservoirs of basins of Shu, Esyl, Tobol, Sirdariya rivers for long-term cycle

    Directory of Open Access Journals (Sweden)

    Sofya Romanova

    2012-12-01

    Full Text Available The analysis of the literature and materials of own research into the regime of the main polluting components and the chemical composition of water in rivers and lakes of Shu, Esil, Tobol, the Syr Darya basins in the long-term cycle. The background of hydrochemical regime of the rivers at the modern period has been investigated. The water of the rivers is contaminated with mineral and organic origin substances (mostly with the compounds of manganese, fluoride, phosphate, nitrate and nitrogen nitrite have shown which is entering to the river due to natural and anthropogenic factors. The total mineralization of river water downstream in the majority of cases is increased.

  20. Floquet theory of river ecomorphodynamics

    Science.gov (United States)

    Bertagni, Matteo; Perona, Paolo; Camporeale, Carlo

    2017-04-01

    Most of world population lives close and depends on freshwaters and related ecosystems. As dramatic consequence, 48% of all rivers worldwide are hydrologically altered. Although mankind lives by and controls river systems since millennia, a complete physically-based understanding of the links among the various processes involved still remains elusive. Three fundamental aspects control the physical state of natural rivers: flow stochasticity, sediment transport and vegetation dynamics. The present work tries to shed light on the bonds among these processes, following a temporal flow for the river dynamics. During a particularly extreme flood event any previous ecomorphological pattern is erased by the flow. However, sediment transport triggers the formation of migrating bedforms, called free bars. Through a nonlinear analysis, with center manifold projection, a long analytical expression is obtained for the bars amplitude, thus completely defining bars geometry in the parameters space. Once the formative event is extinguished, the flow rate decreases and the recently formed bars can partially emerge from water. At this point vegetation develops over the bare bars depending on flow stochasticity. As a realistic model for the flow stochasticity the compound Poisson process is considered. However, in order to make the computation analytically feasible, the stochastic time series for the discharge is replaced with an equivalent periodic one, obtained as a sequence of a typical average event of the stochastic series. In this manner, the new periodic streamflow signal, preserves the same statistical properties of its stochastic correspondent. The periodic equation for the vegetation dynamics can thus be spatially solved through Floquet theory, gaining which portion of the bar is asymptotically colonised by vegetation. In conclusion, this is the first theoretical work linking the trend of the vegetated area with the flow parameters, and confirming that high flow

  1. Communicating River Level Data and Information to Stakeholders with Different Interests

    Science.gov (United States)

    Macleod, K.; Sripada, S.; Ioris, A.; Arts, K.; van der Wal, R.

    2012-12-01

    There is a need to increase the effectiveness of how river level data are communicated to a range of stakeholders with an interest in river level information to increase the use of data collected by regulatory agencies. Currently, river level data is provided to members of the public through a web site without any formal engagement with river users having taken place. In our research project called wikiRivers, we are working with the suppliers of river level data as well as the users of this data to explore and improve from the user perspective how river level data and information is made available online. We are focusing on the application of natural language generation technology to create textual summaries of river level data tailored for specific interest groups. These tailored textual summaries will be presented among other modes of information presentation (e.g. maps and visualizations) with the aim to increase communication effectiveness. Natural language generation involves developing computational models that use non-linguistic input data to produce natural language as their output. Acquiring accurate correct system knowledge for natural language generation is a key step in developing such an effective computer software system. In this paper we set out the needs for this project based on discussions with the stakeholder who supplies the river level data and current cyberinfrastructure and report on what we have learned from those individuals and groups who use river level data. Stages in the wikiRivers stakeholder identification, engagement and cyberinfrastructure development. S1- interviews with collectors and suppliers of river level data. S2- river level data stakeholder analysis, including analysis of their interests in individual river networks in Scotland and what they require from the cyberinfrastructure. S3-5 Iterative development and testing of cyberinfrastructure and modelling of river level data with domain and stakeholder knowledge.

  2. INEEL Subregional Conceptual Model Report; Volume 1 - Summary of Existing Knowledge of Natural and Anthropogenic Influences Governing Subsurface Contaminant Transport in the INEEL Subregion of the Eastern Snake River Plain

    Energy Technology Data Exchange (ETDEWEB)

    Wichlacz, Paul Louis; Orr, Brennan

    2002-08-01

    The National Research Council has defined a conceptual model as ''an evolving hypothesis identifying the important features, processes, and events controlling fluid flow and contaminant transport of consequence at a specific field site in the context of a recognized problem''. Presently, several subregional conceptual models are under development at the Idaho National Engineering and Environmental Laboratory (INEEL). Additionally, facility-specific conceptual models have been described as part of INEEL environmental restoration activities. Compilation of these models is required to develop a comprehensive conceptual model that can be used to strategically plan for future groundwater research activities at the INEEL. Conceptual models of groundwater flow and contaminant transport at the INEEL include the description of the geologic framework, matrix hydraulic properties, and inflows and outflows. They also include definitions of the contaminant source term and contaminant transport mechanisms. The geologic framework of the INEEL subregion is described by the geometry of the system, stratigraphic units within the system, and structural features that affect groundwater flow and contaminant transport. These elements define geohydrologic units that make up the Snake River Plain Aquifer (SRPA). The United States Geological Survey (USGS) conceptual model encompasses approximately 1,920 mi2 of the eastern Snake River Plain. The Waste Area Group (WAG)-10 model includes the USGS area and additional areas to the northeast and southeast. Both conceptual models are bounded to the northwest by the Pioneer Mountains, Lost River Range, and Lemhi Mountains. They are bounded to the southeast by groundwater flow paths determined from aquifer water-level contours. The upgradient extent of the USGS model is a water-level contour that includes the northeastern boundary of the INEEL. The WAG-10 model includes more of the Mud Lake area to utilize previous estimates of

  3. Assessing river health in Europe and Switzerland

    Science.gov (United States)

    Milano, Marianne; Chèvre, Nathalie; Reynard, Emmanuel

    2017-04-01

    River conditions and welfare of aquatic ecosystems are threatened by anthropogenic and climatic changes. The release of personal-care products, pharmaceuticals and crop protection products is increasing and climate change is likely to cause significant changes in hydrological regimes affecting water resources' capacity to dissolve pollutants. Assessing river health, i.e. the ability of a river to support and maintain a balanced ecosystem close to the natural habitat, is thus of major concern to ensure the development of ecosystems and to provide enough clean useable water to users. Such studies involve physical, chemical and biological processes and characteristics. In Europe and Switzerland, standardized procedures have been developed to assess the hydromorphological, ecological and toxicological status of rivers. The European Water Framework Directive sets ecological requirements and chemical guidelines while the Swiss Modular Stepwise Procedure suggests methods to apprehend ecological deficits and promote water management plans. In this study, both procedures were applied and compared in order (i) to address their capacity to follow-up the spatial and temporal variability of the river's water quality and (ii) to identify challenges that still need to be addressed to assess river's health. Applied on the Boiron River (canton of Vaud, Switzerland) for a 11-year period (2005-2015), both frameworks highlight that no section of the river currently meets a good environmental state. This river flows through a diversified agricultural area causing a progressive deterioration of its chemical and biological quality. The two methods also identify two periods of time with significant changes of the river's water quality. The 2009-2011 period is characterized by a significant deterioration of the river's ecological and toxicological state due to severe low flows and an increased use of pesticides. However, since 2013, an improvement in water quality is identified in

  4. Greenhouse gases emission from the sewage draining rivers.

    Science.gov (United States)

    Hu, Beibei; Wang, Dongqi; Zhou, Jun; Meng, Weiqing; Li, Chongwei; Sun, Zongbin; Guo, Xin; Wang, Zhongliang

    2018-01-15

    Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) concentration, saturation and fluxes in rivers (Beitang drainage river, Dagu drainage rive, Duliujianhe river, Yongdingxinhe river and Nanyunhe river) of Tianjin city (Haihe watershed) were investigated during July and October in 2014, and January and April in 2015 by static headspace gas chromatography method and the two-layer model of diffusive gas exchange. The influence of environmental variables on greenhouse gases (GHGs) concentration under the disturbance of anthropogenic activities was discussed by Spearman correlative analysis and multiple stepwise regression analysis. The results showed that the concentration and fluxes of CO2, CH4 and N2O were seasonally variable with >winter>fall>summer, spring>summer>winter>fall and summer>spring>winter>fall for concentrations and spring>summer>fall>winter, spring>summer>winter>fall and summer>spring>fall>winter for fluxes respectively. The GHGs concentration and saturation were higher in comprehensively polluted river sites and lower in lightly polluted river sites. The three GHGs emission fluxes in two sewage draining rivers of Tianjin were clearly higher than those of other rivers (natural rivers) and the spatial variation of CH4 was more obvious than the others. CO2 and N2O air-water interface emission fluxes of the sewage draining rivers in four seasons were about 1.20-2.41 times and 1.13-3.12 times of those in the natural rivers. The CH4 emission fluxes of the sewage draining rivers were 3.09 times in fall to 10.87 times in spring of those in the natural rivers in different season. The wind speed, water temperature and air temperature were related to GHGs concentrations. Nitrate and nitrite (NO3-+NO2--N) and ammonia (NH4+-N) were positively correlated with CO2 concentration and CH4 concentration; and dissolved oxygen (DO) concentration was negatively correlated with CH4 concentration and N2O concentration. The effect of human activities on carbon and

  5. River Corridors (Jan 2, 2015)

    Data.gov (United States)

    Vermont Center for Geographic Information — River corridors are delineated to provide for the least erosive meandering and floodplain geometry toward which a river will evolve over time. River corridor maps...

  6. Sustainable management of river oases along the Tarim River (SuMaRiO) in Northwest China under conditions of climate change

    OpenAIRE

    Rumbaur, C.;Thevs, N.;Disse, M.;Ahlheim, M.;Brieden, A.;Cyffka, B.;Duethmann, D.;Feike, T.;Frör, O.;Gärtner, P.;Halik, Ü.;Hill, J.;Hinnenthal, M.;Keilholz, P.;Kleinschmit, B.;Krysanova, V.;Kuba, M.;Mader, S.;Menz, C.;Othmanli, H.;Pelz, S.;Schroeder, M.;Siew, T. F.;Stender, V.;Stahr, K.;Thomas, F. M.;Welp, M.;Wortmann, M.;Zhao, X.;Chen, X.;Jiang, T.;Luo, J.;Yimit, H.;Yu, R.;Zhang, X.;Zhao, C.

    2017-01-01

    The Tarim River basin, located in Xinjiang, NW China, is the largest endorheic river basin in China and one of the largest in all of Central Asia. Due to the extremely arid climate, with an annual precipitation of less than 100 mm, the water supply along the Aksu and Tarim rivers solely depends on river water. This is linked to anthropogenic activities (e.g., agriculture) and natural and semi-natural ecosystems as both compete for water. The ongoing increase in water consumptio...

  7. How Does the Niagara Whirlpool Get Involved in Niagara River Self-Purification?

    OpenAIRE

    Fisenko, Anatoliy I.

    2013-01-01

    The Niagara River self-purification through the natural formation of froth at a site of the Niagara Whirlpool basin has been investigated. It is shown that the naturally formed froth on the water surface of the Niagara Whirlpool contains a greater concentration of nutrients, trace metals and phenol in comparison to subsurface water. The natural pollutants removal process is explained in detail. As a result, the Niagara River at the Niagara Whirlpool basin possesses its own natural capacity to...

  8. Origin of the onset of meandering of a straight river

    Science.gov (United States)

    Dey, Subhasish; Ali, Sk Zeeshan

    2017-08-01

    In this paper, to explore the origin of the onset of meandering of a straight river, we, first, analyse the linear stability of a straight river. We discover that the natural perturbation modes of a straight river maintain an equilibrium state by confining themselves to an onset wavenumber band that is dependent on the flow regimes, aspect ratio, relative roughness number and Shields number. Then, we put forward a phenomenological description of the onset of meandering of a straight river. Its mechanism is governed by turbulent flow, with counter-rotation of neighbouring large-scale or macro-turbulent eddies in succession to generate the processes of alternating erosion and deposition of sediment grains of the riverbed. This concept is explained by a theorem (universal scaling law) stemming from the phenomenology of a turbulent energy cascade to provide a quantitative insight into the criterion for the onset of meandering of a straight river. It is revealed from this universal scaling law that, at the onset of meandering of a river, the longitudinal riverbed slope is a unique function of the river width, flow discharge and sediment grain size. This unique functional relationship is corroborated by the data obtained from the measurements in natural and model rivers.

  9. Diazotrophy in alluvial meadows of subarctic river systems.

    Science.gov (United States)

    DeLuca, Thomas H; Zackrisson, Olle; Bergman, Ingela; Díez, Beatriz; Bergman, Birgitta

    2013-01-01

    There is currently limited understanding of the contribution of biological N2 fixation (diazotrophy) to the N budget of large river systems. This natural source of N in boreal river systems may partially explain the sustained productivity of river floodplains in Northern Europe where winter fodder was harvested for centuries without fertilizer amendments. In much of the world, anthropogenic pollution and river regulation have nearly eliminated opportunities to study natural processes that shaped early nutrient dynamics of large river systems; however, pristine conditions in northern Fennoscandia allow for the retrospective evaluation of key biochemical processes of historical significance. We investigated biological N2 fixation (diazotrophy) as a potential source of nitrogen fertility at 71 independent floodplain sites along 10 rivers and conducted seasonal and intensive analyses at a subset of these sites. Biological N2 fixation occurred in all floodplains, averaged 24.5 kg N ha(-1) yr(-1) and was down regulated from over 60 kg N ha(-1) yr(-1) to 0 kg N ha(-1) yr(-1) by river N pollution. A diversity of N2-fixing cyanobacteria was found to colonize surface detritus in the floodplains. The data provide evidence for N2 fixation to be a fundamental source of new N that may have sustained fertility at alluvial sites along subarctic rivers. Such data may have implications for the interpretation of ancient agricultural development and the design of contemporary low-input agroecosystems.

  10. Diazotrophy in alluvial meadows of subarctic river systems.

    Directory of Open Access Journals (Sweden)

    Thomas H DeLuca

    Full Text Available There is currently limited understanding of the contribution of biological N2 fixation (diazotrophy to the N budget of large river systems. This natural source of N in boreal river systems may partially explain the sustained productivity of river floodplains in Northern Europe where winter fodder was harvested for centuries without fertilizer amendments. In much of the world, anthropogenic pollution and river regulation have nearly eliminated opportunities to study natural processes that shaped early nutrient dynamics of large river systems; however, pristine conditions in northern Fennoscandia allow for the retrospective evaluation of key biochemical processes of historical significance. We investigated biological N2 fixation (diazotrophy as a potential source of nitrogen fertility at 71 independent floodplain sites along 10 rivers and conducted seasonal and intensive analyses at a subset of these sites. Biological N2 fixation occurred in all floodplains, averaged 24.5 kg N ha(-1 yr(-1 and was down regulated from over 60 kg N ha(-1 yr(-1 to 0 kg N ha(-1 yr(-1 by river N pollution. A diversity of N2-fixing cyanobacteria was found to colonize surface detritus in the floodplains. The data provide evidence for N2 fixation to be a fundamental source of new N that may have sustained fertility at alluvial sites along subarctic rivers. Such data may have implications for the interpretation of ancient agricultural development and the design of contemporary low-input agroecosystems.

  11. Removal of river embankments and the modelled effects on river-floodplain hydrodynamics

    Science.gov (United States)

    Clilverd, Hannah; Thompson, Julian; Heppell, Kate; Sayer, Carl; Axmacher, Jan

    2015-04-01

    the restored river reach (~400 m), and improved free drainage back to the river. Our results suggest that embankment removal can increase river-floodplain hydrological connectivity to form a more natural wetland ecotone driven by frequent flood disturbance. This has important implications for the planning and management of river restoration projects which aim to enhance floodwater storage, river water quality and floodplain species composition.

  12. Chemical and stable isotopic composition of water and gas in the Fort Union Formation of the Powder River Basin, Wyoming and Montana: Evidence for water/rock interaction and the biogenic origin of coalbed natural gas

    Science.gov (United States)

    Rice, Cynthia A.; Flores, Romeo M.; Stricker, Gary D.; Ellis, Margaret S.

    2008-01-01

    Significant amounts (> 36 million m3/day) of coalbed methane (CBM) are currently being extracted from coal beds in the Paleocene Fort Union Formation of the Powder River Basin of Wyoming and Montana. Information on processes that generate methane in these coalbed reservoirs is important for developing methods that will stimulate additional production. The chemical and isotopic compositions of gas and ground water from CBM wells throughout the basin reflect generation processes as well as those that affect water/rock interaction. Our study included analyses of water samples collected from 228 CBM wells. Major cations and anions were measured for all samples, δDH2O and δ18OH2O were measured for 199 of the samples, and δDCH4 of gas co-produced with water was measured for 100 of the samples. Results show that (1) water from Fort Union Formation coal beds is exclusively Na–HCO3-type water with low dissolved SO4 content (median water/rock interactions, such as cation exchange on clay minerals and precipitation/dissolution of CaCO3 and SO4 minerals, account for the accumulation of dissolved Na and depletion of Ca and Mg; (3) bacterially-mediated oxidation–reduction reactions account for high HCO3 (270–3310 mg/L) and low SO4 (median water line, indicating that the original meteoric water has been influenced by methanogenesis and by being mixed with surface and shallow groundwater.

  13. Don't fight the site: three geomorphic considerations in catchment-scale river rehabilitation planning.

    Science.gov (United States)

    Brierley, Gary; Fryirs, Kirstie

    2009-06-01

    Three geomorphic considerations that underpin the design and implementation of realistic and strategic river conservation and rehabilitation programs that work with the nature are outlined. First, the importance of appreciating the inherent diversity of river forms and processes is discussed. Second, river dynamics are appraised, framing the contemporary behavioral regime of a reach in relation to system evolution to explain changes to river character and behavior over time. Third, the trajectory of a reach is framed in relation to downstream patterns of river types, analyzing landscape connectivity at the catchment scale to interpret geomorphic river recovery potential. The application of these principles is demonstrated using extensive catchment-scale analyses of geomorphic river responses to human disturbance in the Bega and Upper Hunter catchments in southeastern Australia. Differing implications for reach- and catchment-scale rehabilitation planning prompt the imperative that management practices work with nature rather than strive to 'fight the site.'

  14. Modelling river dune development

    NARCIS (Netherlands)

    Paarlberg, Andries; Weerts, H.J.T.; Dohmen-Janssen, Catarine M.; Ritsema, I.L; Hulscher, Suzanne J.M.H.; van Os, A.G.; Termes, A.P.P.

    2005-01-01

    Since river dunes influence flow resistance, predictions of dune dimensions are required to make accurate water level predictions. A model approach to simulate developing river dunes is presented. The model is set-up to be appropriate, i.e. as simple as possible, but with sufficient accuracy for

  15. Evolution of river dolphins.

    Science.gov (United States)

    Hamilton, H; Caballero, S; Collins, A G; Brownell, R L

    2001-03-07

    The world's river dolphins (Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeographical and evolutionary implications raised by the important, although limited, fossil record of river dolphins. We present a hypothesis of river dolphin relationships based on phylogenetic analysis of three mitochondrial genes for 29 cetacean species, concluding that the four genera represent three separate, ancient branches in odontocete evolution. Our molecular phylogeny corresponds well with the first fossil appearances of the primary lineages of modern odontocetes. Integrating relevant events in Tertiary palaeoceanography, we develop a scenario for river dolphin evolution during the globally high sea levels of the Middle Miocene. We suggest that ancestors of the four extant river dolphin lineages colonized the shallow epicontintental seas that inundated the Amazon, Paraná, Yangtze and Indo-Gangetic river basins, subsequently remaining in these extensive waterways during their transition to freshwater with the Late Neogene trend of sea-level lowering.

  16. Nipigon River landslide, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishna, H.S.; Lau, K.C.

    1992-11-24

    On April 23, 1990, a landslide occurred on the east bank of the Nipigon River in Ontario, 8 km downstream from the Alexander Generating Station. A study was initiated to assess the impact of river level fluctuations caused by the hydropower plant operation on the downstream banks of the river. A detailed geotechnical investigation and field study of river drawdown effects on the riverbank slopes were performed. A final analysis of the failure is presented which shows that the high groundwater conditions and soft soils present in the area led to the massive landslide. The impact of the river level fluctuations on the slope stability was found to be minor compared to that of the high groundwater conditions that were produced by the rapid thaw of snow and infiltration in the recharge area. 15 refs., 16 figs., 6 tabs.

  17. Biological surveys on the Savannah River in the vicinity of the Savannah River Plant (1951-1976)

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, R. A.

    1982-04-01

    In 1951, the Academy of Natural Sciences of Philadelphia was contracted by the Savannah River Plant to initiate a long-term monitoring program in the Savannah River. The purpose of this program was to determine the effect of the Savannah River Plant on the Savannah River aquatic ecosystem. The data from this monitoring program have been computerized by the Savannah River Laboratory, and are summarized in this report. During the period from 1951-1976, 16 major surveys were conducted by the Academy in the Savannah River. Water chemistry analyses were made, and all major biological communities were sampled qualitatively during the spring and fall of each survey year. In addition, quantitative diatom data have been collected quarterly since 1953. Major changes in the Savannah River basin, in the Savannah River Plant's activities, and in the Academy sampling patterns are discussed to provide a historical overview of the biomonitoring program. Appendices include a complete taxonomic listing of species collected from the Savannah River, and summaries of the entire biological and physicochemical data base.

  18. Effect of incubation temperature on post-embryonic survival and growth of steelhead in a natural stream and a hatchery (Study sites: Dworshak Hatchery and North Fork Palouse River; Stocks: Dworshak hatchery; Year classes: 1994 and 1995): Chapter 5

    Science.gov (United States)

    Rubin, Stephen P.; Reisenbichler, Reginald R.; Wetzel, Lisa A.; Stenberg, Karl D.; Baker, Bruce M.; Rubin, Stephen P.; Reisenbichler, Reginald R.; Wetzel, Lisa A.; Hayes, Michael C.

    2012-01-01

    We tested whether varying incubation temperatures to match development between embryos from different spawning dates affected survival and growth of unfed steelhead Oncorhynchus mykiss fry released in a stream and in hatchery ponds. Hatchery steelhead returning to the Clearwater River, Idaho were artificially spawned on two dates separated by a four week interval. Progeny from the early date (ExE, from early males and early females) were incubated in chilled (7°C) water and those from the late date (LxL) in ambient (12°C) water until developmental stage matched. A third group, created by fertilizing eggs from late females with cryopreserved milt from early males (ExL), was included to control for any genetic differences between early and late returning adults. Survival in the stream to 3 and 15 months after release was similar among crosses. Survival in the hatchery to near the end of the standard one year rearing period was similar among crosses for one of two year - classes but different for the other; however, it was difficult to ascribe the differences (ExL>ExE; LxL intermediate but closer to ExE) to incubation temperature differences. We conclude that there was little if any effect of incubation temperature on survival. Length of juveniles of one year - class differed among crosses in the stream and in the hatchery. Length of the other year - class differed among crosses in one pond at the hatchery but not in the other pond or in the stream. When length differed the pattern was always the same: ExE>LxL; ExL intermediate but closer to LxL. We speculate that incubation temperature may have affected growth of juveniles, and in particular that a longer period of incubation in chilled water may have caused fast juvenile growth relative to a shorter incubation period in ambient water.

  19. Measurement of tritium in the Sava and Danube Rivers.

    Science.gov (United States)

    Grahek, Željko; Breznik, Borut; Stojković, Ivana; Coha, Ivana; Nikolov, Jovana; Todorović, Nataša

    2016-10-01

    Two nuclear power plants (NPP), the KrškoNPP (Slovenia) on the Sava River and the Paks NPP (Hungary) on the Danube River, are located in the immediate vicinity of Croatia and Serbia. Some of the radioactivity monitoring around the NPPs involves measuring tritium activity in the waters of rivers and wells. The authors present the tritium measurement results taken over several years from the Sava and Danube Rivers, and groundwater. The measurements were carried out in two laboratories including an impact assessment of the tritium released into the rivers and groundwater. The routine methods for determining tritium (with/without electrolytic enrichment) were tested in two laboratories using two different instruments, a Tri-Carb 3180 and Quantulus 1220. Detection limits for routine measurements were calculated in compliance with ISO 11929 and Currie relations, and subsequently the results were compared with those determined experimentally. This has shown that tritium can be reliably determined within a reasonable period of time when its activity is close to the calculated detection limit. The Krško NPP discharged 62 TBq of tritium into the River Sava over a period of 6 years (23% of permitted activity, 45 TBq per year). The natural level of tritium in the Sava River and groundwater is 0.3-1 Bq/l and increases when discharges exceed 1 TBq per month. Usually, the average monthly activity in the Sava River and groundwater is maintained at a natural level. The maximum measured activity was 16 Bq/l in the Sava River and 9.5 Bq/l in groundwater directly linked to the river. In the majority of water samples from the Danube River, measured tritium activity ranged between 1 and 2 Bq/l. The increased tritium levels in the Danube River are more evident than in the Sava River because tritium activity above 1.5 Bq/l appears more frequently on the Danube River. All measured values were far below the allowed tritium limit in drinking water. Dose assessment has shown that

  20. Managing the wetlands. People and rivers: Africa.

    Science.gov (United States)

    Dugan, P

    1993-01-01

    At the current population growth rate in Africa, the population will reach 1 billion by 2010. Water is needed to sustain these people, yet rainfall in Africa is erratic. Africans are already confronting a shortage of freshwater. Agriculture supports 66% of the population of sub-Saharan Africa. Sound agricultural development is needed to curb rural-urban migration, but a constant supply of freshwater is essential. Major rivers (the Limpopo in southern Africa and the Save/Sabi in Zimbabwe and Mozambique) now flow only seasonally. The flows of the Chari-Logona, the Nile, and the Zambezi are falling. Continual mismanagement of Africa's river basins coupled with current projections of global climate change will expand desiccation. All but the White Nile and the Zaire rivers flood seasonally every year, thereby expanding Africa's wetlands. Wetlands have been targeted for development projects (e.g., hydroelectric projects and large dams), largely to meet urban-industrial demands. Development planners tend to ignore the economic value of the wetlands. For example, the Niger Inland Delta sustains 550,000 people, 1 million cattle, and 1 million sheep. Wetlands replenish ground water and serve as natural irrigation. River basin planning often results in environmentally disastrous schemes which do not understand local management practices. Hydrologists, engineers, geologists, and economics design these schemes, but sociologists, anthropologists, and development experts should be included. The unfinished Jonglei Canal in southern Sudan would have adversely affected 400,000 pastoralists. The Volta River Authority's Akosombo Dam displaced 84,000 people and flooded the most productive agricultural land in Ghana. A sustainable future in Africa depends on understanding the interactions of human uses and the ways in which they relate to the natural variations in river flow. The IUCN Wetlands Programme, based on the principles of the World Conservation Strategy, is working with

  1. Using array seismology to quantify river physics

    Science.gov (United States)

    Gimbert, F.

    2016-12-01

    Seismic ground motion measurements nearby rivers are sensitive to bedload sediment transport and turbulent fluid flow operating at river beds, both of which are major control on fluvial erosion but yet remain poorly known due to lacking observations. Seismic observations thus provide a valuable opportunity to improve our understanding of fluvial dynamics and its control on crustal erosion. However, although recently proposed theoretical frameworks provided solid grounds to link fluvial processes with seismic signal properties, a better understanding of river physics from seismic signals needs investigating turbulent flow and bedload seismic source functions from direct field observations. Here we use seismic array processing to invert river seismic source force functions and discuss the various river mechanisms that control properties of the seismic wave field. We report new seismic measurements conducted under various flow conditions at two mountain rivers with drastically different geometries: the narrow (1 m), steep ( 5 to 15%) and shallow flows ( 10 to 40 cm deep) of the Les Bossons River (Chamonix, French Alps), and the much wider ( 50 m), gentler ( 1 to 2%) and deeper flows ( 2 to 4 m deep) of the Kali Gandaki River (Lete, Nepal Himalayas). At these sites, we invert for ground velocity structure and river seismic source characteristics from the analysis of both impulsive arrivals and the continuous noise field. We report distinct spectral and directional properties between the sediment transport and the turbulent flow sources. We relate source force characteristics to physical components of sediment transport and turbulent flow dynamics such as mainly the directionality of grain impacts and the associated grain transport modes (saltation, rolling, sliding), as well as the directionality of fluid forces applied on river bed grains and the respective drag, lift and cross stream forces. To our knowledge, this is the first time that such physics of bedload

  2. Numerical modelling of river processes: flow and river bed deformation

    NARCIS (Netherlands)

    Tassi, P.A.

    2007-01-01

    The morphology of alluvial river channels is a consequence of complex interaction among a number of constituent physical processes, such as flow, sediment transport and river bed deformation. This is, an alluvial river channel is formed from its own sediment. From time to time, alluvial river

  3. Tidal controls on river delta morphology

    Science.gov (United States)

    Hoitink, A. J. F.; Wang, Z. B.; Vermeulen, B.; Huismans, Y.; Kästner, K.

    2017-09-01

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world’s largest deltas intensifies. Harbour development, construction of flood defences, sand mining and land reclamation emerge as key contemporary factors that exert an impact on delta morphology. Tides interacting with river discharge can play a crucial role in the morphodynamic development of deltas under pressure. Emerging insights into tidal controls on river delta morphology suggest that--despite the active morphodynamics in tidal channels and mouth bar regions--tidal motion acts to stabilize delta morphology at the landscape scale under the condition that sediment import during low flows largely balances sediment export during high flows. Distributary channels subject to tides show lower migration rates and are less easily flooded by the river because of opposing non-linear interactions between river discharge and the tide. These interactions lead to flow changes within channels, and a more uniform distribution of discharge across channels. Sediment depletion and rigorous human interventions in deltas, including storm surge defence works, disrupt the dynamic morphological equilibrium and can lead to erosion and severe scour at the channel bed, even decades after an intervention.

  4. Draft algorithm for Danube River Revitalization

    Directory of Open Access Journals (Sweden)

    MIERLĂ MARIAN

    2012-09-01

    Full Text Available Nowadays more and more scientific communities, decisional factors and the most of the inhabitants had realised that there is no future without revering the nature by its all component. The most important component of the Planet Earth is water, in all its conditions and locations. The fresh water is one of the main forms of the water thathas high value for the entire humanity. Most of the fresh waters are stoked into lakes which are permanently or temporary supplied by permanent and respective temporary rivers. In the past, people did not consider water as important as it is in present days and did not take care of its quality and quantity. Therefore, there were built a lot of industrial pollutant plants on immediate proximity, hydro-technical works that changed its shapes and courses, maleficent water consumption entities (e.g. for irrigations, for residential purpose, industrial etc.. All these works did serious changes in the natural (equilibrate water bodies status in order to alter its natural functions. To win back these natural functions the affected water bodies should be restored. This paper presents an attempt to draw a set of rules to be followed in solving the problem of rivers revitalization, as a study case is about the Danube River. These rules involve scientific specialists, decisional factors and social communities. The beneficiary of the results by applying this set of rules is the entire socio-ecologic system.

  5. 77 FR 49775 - Beaverhead-Deerlodge National Forest, Wisdom and Wise River Ranger Districts; Montana; North and...

    Science.gov (United States)

    2012-08-17

    ... Forest Service Beaverhead-Deerlodge National Forest, Wisdom and Wise River Ranger Districts; Montana..., Wisdom/Wise River District Ranger at (406) 689-3243 or via email at [email protected] . Individuals who... Official The Wisdom/Wise River District Ranger will be the responsible official. Nature of Decision To Be...

  6. Degradation and recovery of the freshwater fauna in the lower sections of the rivers Rhine and Meuse

    NARCIS (Netherlands)

    Vaate, bij de A.

    2003-01-01

    Exponential increase of anthropogenic stress in European rivers, like Rhine and Meuse, started several centuries ago when inhabitants of floodplains used them for an increasing number of purposes. Step by step, the river basins lost their naturalness and ecological integrity. Usually, river

  7. Yakima River Spring Chinook Enhancement Study, 1985 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Fast, David E.

    1986-02-01

    The purpose was to evaluate enhancement methodologies that can be used to rebuild runs of spring chinook salmon in the Yakima River basin. The objectives were to: (1) determine the abundance, distribution and survival of naturally produced fry and smolts in the Yakima River; (2) evaluate different methods of fry and smolt supplementation into the natural rearing environment while maintaining as much as possible the gentic integrity of naturally produced stocks; (3) locate and define areas in the watershed which may be used for the rearing of spring chinook; (4) define strategies for enhancing natural production of spring chinook in the Yakima River; and (5) determine physical and biological limitations for production within the system.

  8. Hydrology of the Po River: looking for changing patterns in river discharge

    Directory of Open Access Journals (Sweden)

    A. Montanari

    2012-10-01

    Full Text Available Scientists and public administrators are devoting increasing attention to the Po River, in Italy, in view of concerns related to the impact of increasing urbanisation and exploitation of water resources. A better understanding of the hydrological regime of the river is necessary to improve water resources management and flood protection. In particular, the analysis of the effects of hydrological and climatic change is crucial for planning sustainable development and economic growth. An extremely interesting issue is to inspect to what extent river flows can be naturally affected by the occurrence of long periods of water abundance or scarcity, which can be erroneously interpreted as irreversible changes due to human impact. In fact, drought and flood periods alternatively occurred in the recent past in the form of long-term fluctuations. This paper presents advanced graphical and analytical methods to gain a better understanding of the temporal distribution of the Po River discharge. In particular, we present an analysis of river flow variability and persistence properties, to gain a better understanding of natural patterns, and in particular long-term changes, which may affect the future flood risk and availability of water resources.

  9. Population Dynamics and Natural Resources in the Volta in the ...

    African Journals Online (AJOL)

    Also, population growth is causing shortfalls in agricultural land, deforestation and high demand on water resources in some of the sub-basins of the Volta River Keywords: Population, Natural resources, Volta River Basin, Human Settlement Land Use/Coverage Change Ghana Journal of Development Studies Vol.

  10. Transport and Retention of Nitrogen, Phosphorus and Carbon in North America’s Largest River Swamp Basin, the Atchafalaya River Basin

    OpenAIRE

    Y. Jun Xu

    2013-01-01

    Floodplains and river corridor wetlands may be effectively managed for reducing nutrients and carbon. However, our understanding is limited to the reduction potential of these natural riverine systems. This study utilized the long-term (1978–2004) river discharge and water quality records from an upriver and a downriver location of the Atchafalaya River to quantify the inflow, outflow, and inflow–outflow mass balance of total Kjeldahl nitrogen (TKN = organic nitrogen + ammonia nitrogen), nitr...

  11. Mixing in a river

    Energy Technology Data Exchange (ETDEWEB)

    Bernath, L.; Menegus, R.L.; Ring, H.F.

    1956-05-09

    Many rivers are burdened with tributary streams of warm water and/or liquid wastes containing dissolved or suspended matter. The warm water and waste matter mix thoroughly with the river water some distance downstream from the point of entry of the tributary, but near the point of entry there may be high local temperatures or concentrations of waste. It is often necessary to know the local temperatures or concentrations of waste. The authors have used a formula for computing the turbulent mixing that takes place in such a situation; this formula fits quite well in the case of one Southern river.

  12. Environmental flow assessment for river Trebizat, BiH

    Science.gov (United States)

    Smolar-Zvanut, N.; Kupusovic, E.; Vucijak, B.; Mijatovic, A.; Grizelj, Z.; Antonelli, F.

    2009-04-01

    The alteration of the water flow downstream of dams is one of the most stressful factors influencing the aquatic and riverine ecosystem. The environmental flow assessment is a tool for finding the balance between water use by humans and nature and ensuring a long-term and good quality water supply both for human purposes and for ecosystems. In 2007/08 WWF has implemented a project in the Neretva basin (Bosnia and Herzegovina) with a focus on environmental flow evaluation for the river Trebizat, located in the western region of Herzegovina. The water regime of the Trebizat river is affected by the abstraction of its water for hydropower plants, irrigation and fish farming not to mention pollution problems. The Trebizat river flows through an area of remarkable ecological value hosting also protected areas (the travertine-formation around Kravice waterfall). The main aim of this paper is to present the results of the application of a methodology for environmental flow assessment, namely the GEP methodology (guaranteed ecological flow). It belongs to the category of hydrological environmental flow assessment methods and the test was done to assess the environmental flow in the river Trebizat. Using existing hydrological data as well as samples specifically collected on the field, the environmental flow was assessed applying the GEP methodology. Additionally, instream ecological values and critical parameters for environmental flow assessment were evaluated. The area was assessed in terms of its geography, climate conditions, historic heritage of the river, demography, geology of the river and its tributaries, river hydrology and morphology, ecological characteristics, river pollution, river use and river management. At five selected sampling sites along the Trebizat river, additional data on macrophytes, phytobenthos and physico-chemical parameters were collected and analysed. Although there have been many negative impacts in recent years on the Trebizat river, the

  13. Sustainable management of river oases along the Tarim River in North-Western China under conditions of climate change

    Science.gov (United States)

    Rumbaur, C.; Thevs, N.; Disse, M.; Ahlheim, M.; Brieden, A.; Cyffka, B.; Doluschitz, R.; Duethmann, D.; Feike, T.; Frör, O.; Gärtner, P.; Halik, Ü.; Hill, J.; Hinnenthal, M.; Keilholz, P.; Kleinschmit, B.; Krysanova, V.; Kuba, M.; Mader, S.; Menz, C.; Othmanli, H.; Pelz, S.; Schroeder, M.; Siew, T. F.; Stender, V.; Stahr, K.; Thomas, F. M.; Welp, M.; Wortmann, M.; Zhao, X.; Chen, X.; Jiang, T.; Zhao, C.; Zhang, X.; Luo, J.; Yimit, H.; Yu, R.

    2014-10-01

    The Tarim River Basin, located in Xinjiang, NW China, is the largest endorheic river basin of China and one of the largest in whole Central Asia. Due to the extremely arid climate with an annual precipitation of less than 100 mm, the water supply along the Aksu and Tarim River solely depends on river water. This applies for anthropogenic activities (e.g. agriculture) as well as for the natural ecosystems so that both compete for water. The on-going increase of water consumption by agriculture and other human activities in this region has been enhancing the competition for water between human needs and nature. Against this background, 11 German and 6 Chinese universities and research institutes formed the consortium SuMaRiO (www.sumario.de), which aims at gaining a holistic picture of the availability of water resources in the Tarim River Basin and the impacts on anthropogenic activities and natural ecosystems caused by the water distribution within the Tarim River Basin. The discharge of the Aksu River, which is the major tributary to the Tarim, has been increasing over the past 6 decades due to enhanced glacier melt. Alone from 1989 to 2011, the area under agriculture more than doubled. Thereby, cotton became the major crop and there was a shift from small-scale farming to large-scale intensive farming. The major natural ecosystems along the Aksu and Tarim River are riparian ecosystems: Riparian (Tugai) forests, shrub vegetation, reed beds, and other grassland. Within the SuMaRiO Cluster the focus was laid on the Tugai forests, with Populus euphratica as dominant tree, because the most productive and species-rich natural ecosystems can be found among those forests. On sites with groundwater distance of less than 7.5 m the annual increments correlated with river runoffs of the previous year. But, the further downstream along the Tarim River, the more the natural river dynamics ceased, which impacts on the recruitment of Populus euphratica. Household surveys

  14. River and river-related drainage area parameters for site investigation program

    Energy Technology Data Exchange (ETDEWEB)

    Blomqvist, P.; Brunberg, A.K. [Uppsala Univ. (Sweden). Dept. of Limnology; Brydsten, L. [Umeaa Univ. (Sweden). Dept. of Ecology and Environmental Science

    2001-05-01

    In this paper, a number of parameters of importance to a determination of the function of running waters as transport channels for material from the continents to the sea are presented. We have assumed that retention mechanisms of material in the river and in the riparian zone will be covered by special investigations but tried to create a platform for such investigations by quantification of the extension of different main habitats. The choice of parameters has been made so that also the nature conservation value of the river can be preliminary established, and includes a general description of the river type and the inherent ecosystem. The material links directly to that presented in a previous report concerning site investigation programmes for lakes. The parameters have been divided into five groups: 1) The location of the object relative important gradients in the surrounding nature; 2) The river catchment area and its major constituents; 3) The river morphometry; 4) The river ecosystem; 5) Human-induced damages to the river ecosystem. The first two groups, principally based on the climate, hydrology, geology and vegetation of the catchment area, represent parameters that can be used to establish the rarity and representativity of the system, and will in the context of site investigation program be used as a basis for generalisation of the results. The third group, the river morphometry parameters, are standard parameters for the outline of sampling programmes and for calculations of the physical extension of key habitats in the system. The fourth group, the ecosystem of the river, includes physical, chemical and biological parameters required for determination of the influence from the terrestrial ecosystem of the catchment area, nutrient status, distribution of different habitats, and presence of fish in the system. In the context of site investigation program, the parameters in these two groups will be used for budget calculations of the flow of energy and

  15. River archaeology - a new tool for historical hydrology

    Energy Technology Data Exchange (ETDEWEB)

    Toth, Attila J [National Office of Cultural Heritage, Budapest (Hungary)], E-mail: attila.toth@koh.hu

    2008-11-01

    River archaeology consists of underwater research on the rivers themselves. It is also concerned with the archaeology of the valleys/floodplains with special attention to human-environmental interactions (reconstructing landscape, the environment, economy and society from material culture and traces of human impact on their surroundings). As historical hydrology is concerned with similar questions, from the hydrologist's point of view, the combination of different approaches offers the possibilities for fruitful cooperation for both disciplines. The intent of this paper is to present the type, nature and limitations of this part of the archaeological record through recent work in the Drava River basin.

  16. Uranium waste disposal at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.R.; McDonell, W.R.; Wilhite, E.L.

    1990-01-01

    The Savannah River Site generates waste containing depleted, natural, and enriched uranium residue. The past and current practice for disposal of this waste at the Savannah River Site have been assessed using radionuclide pathway analysis to estimate environmental impact of closure alternatives for existing disposal sites, and to assist in the development of improved disposal facilities in the near future. This paper outlines the status of uranium waste management technology as currently practiced to maintain the environmental impact within an acceptable limit at the Savannah River Site, and indicates those steps being taken to improve future operations.

  17. Uranium waste disposal at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.R.; McDonell, W.R.; Wilhite, E.L.

    1990-12-31

    The Savannah River Site generates waste containing depleted, natural, and enriched uranium residue. The past and current practice for disposal of this waste at the Savannah River Site have been assessed using radionuclide pathway analysis to estimate environmental impact of closure alternatives for existing disposal sites, and to assist in the development of improved disposal facilities in the near future. This paper outlines the status of uranium waste management technology as currently practiced to maintain the environmental impact within an acceptable limit at the Savannah River Site, and indicates those steps being taken to improve future operations.

  18. How Does the Niagara Whirlpool Get Involved in Niagara River Self-Purification?

    CERN Document Server

    Fisenko, Anatoliy I

    2013-01-01

    The Niagara River self-purification through the natural formation of froth at a site of the Niagara Whirlpool basin has been investigated. It is shown that the naturally formed froth on the water surface of the Niagara Whirlpool contains a greater concentration of nutrients, trace metals and phenol in comparison to subsurface water. The natural pollutants removal process is explained in detail. As a result, the Niagara River at the Niagara Whirlpool basin possesses its own natural capacity to self-purify through the natural formation of froth. We can conclude that the Niagara Whirlpool is a natural source of Niagara River self-purification. The necessity for the long-term research on the sites of Niagara River for developing the remediation strategies is pointed out.

  19. Exchange between a river and groundwater, assessed with hydrochemical data

    Directory of Open Access Journals (Sweden)

    E. Hoehn

    2011-03-01

    Full Text Available We describe the chemical composition of groundwater from an alluvial granular aquifer in a valley fill flood plain (River Thur Valley. The river flows along this valley and is mostly downwelling on its way, indirectly through an unsaturated zone in the upstream part, and directly through the water-saturated bed in the downstream part. River Thur has been channelized with barriers for more than a century. In 1992, the authorities started to restore a section of River Thur with riverbed enlargements. The land use in the flood plain and the seasonal and climatic conditions (e.g., hot dry summer 2003 result in alterations of the natural geochemical composition of the river water. This groundwater is partly to mainly recharged by bank filtration. Several wells exist near the river that draw groundwater for drinking. In some of these wells, the groundwater has a very short residence time in the subsurface of days to weeks. Bed enlargements and other operations for an enhancement of the exchange of water between the river and groundwater increase the contamination risk of the nearby wells. During bank filtration, the groundwater changes gradually its composition, with increasing distance from the river and with depth in the aquifer. From today's changes of the water quality during riverbank filtration, we tried to extrapolate to the groundwater quality that may arise from future river restorations. Today the groundwater body consists of a mixture of groundwater from the seepage of precipitation and from riverbank filtration. The main difference between river water and groundwater results from the microbial activity in riverbed and bank materials. This activity leads to a consumption of O2 and to a higher partial pressure of CO2 in the groundwater. Criteria for the distinction of different groundwater compositions are the distance of a well from the river and the subsurface residence time of the groundwater to reach this well.

  20. Zinc and Its Isotopes in the Loire River Basin, France

    Science.gov (United States)

    Millot, R.; Desaulty, A. M.; Bourrain, X.

    2014-12-01

    The contribution of human activities such as industries, agriculture and domestic inputs, becomes more and more significant in the chemical composition of the dissolved load of rivers. Human factors act as a supplementary key process. Therefore the mass-balance for the budget of catchments and river basins include anthropogenic disturbances. The Loire River in central France is approximately 1010 km long and drains an area of 117,800 km2. In the upper basin, the bedrock is old plutonic rock overlain by much younger volcanic rocks. The intermediate basin includes three major tributaries flowing into the Loire River from the left bank: the Cher, the Indre and the Vienne rivers; the main stream flows westward and its valley stretches toward the Atlantic Ocean. Here, the Loire River drains the sedimentary series of the Paris Basin, mainly carbonate deposits. The lower Loire basin drains pre-Mesozoic basement of the Armorican Massif and its overlying Mesozoic to Cenozoic sedimentary deposits. The Loire River is one of the main European riverine inputs to the Atlantic ocean. Here we are reporting concentration and isotope data for Zn in river waters and suspended sediments from the Loire River Basin. In addition, we also report concentration and isotope data for the different industrial sources within the Loire Basin, as well as data for biota samples such as mussels and oysters from the Bay of Biscay and North Brittany. These organisms are known to be natural accumulators of metal pollutants. Zinc isotopic compositions are rather homogeneous in river waters with δ66Zn values ranging from 0.21 to 0.39‰. This range of variation is very different from anthropogenic signature (industrial and/or agriculture release) that displays δ66Zn values between 0.02 to 0.14‰. This result is in agreement with a geogenic origin and the low Zn concentrations in the Loire River Basin (from 0.8 to 6 µg/L).

  1. Human activities impact on mountain river channels (case study of Kamchatka peninsula rivers)

    Science.gov (United States)

    Ermakova, Aleksandra S.

    2010-05-01

    Human-induced driving factors along with natural environmental changes greatly impact on fluvial regime of rivers. On mountain and semi-mountain territories these processes are developed in the most complicated manner due to man-made activities diversity throughout river basins. Besides these processes are significantly enhanced because of the disastrous natural processes (like volcanic and mud-flow activity) frequent occurrences in mountainous regions. On of the most striking example on the matter is Kamchatka peninsula which is located at the North-West part of Russian Federation. This paper contributes to the study of human activities impact on fluvial systems in this volcanic mountain region. Human effects on rivers directly alter channel morphology and deformations, dynamics of water and sediment movement, aquatic communities or indirectly affect streams by altering the movement of water and sediment into the channel. In case study of Kamchatka peninsula human activities affect fluvial systems through engineering works including construction of bridges, dams and channel diversions and placer mining. These processes are characterized by spatial heterogeneity because of irregular population distribution. Due to specific natural conditions of the peninsula the most populated areas are the valleys of big rivers (rivers Kamchatka, Avacha, Bistraya (Bolshaya), etc) within piedmont and plain regions. These rivers are characterized by very unstable channels. Both with man-made activities this determines wide range of fluvial system changes. Firstly bridges construction leads to island and logjam formation directly near their piers and intensification of channels patterns shifts. Furthermore rivers of the peninsula are distinguished for high water flow velocities and water rate. Incorrect bridge constructions both with significant channel deformations lead to the destructions of the bridges themselves due to intensive bank erosion. Secondly, intensive water flow

  2. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  3. Controls on morphological variability and role of stream power distribution pattern, Yamuna River, western India

    Science.gov (United States)

    Bawa, Nupur; Jain, Vikrant; Shekhar, Shashank; Kumar, Niraj; Jyani, Vikas

    2014-12-01

    Understanding the controls on the morphological variability of river systems constitutes one of the fundamental questions in geomorphic investigation. Channel morphology is an important indicator of river processes and is of significance for mapping the hydrology-ecologic connectivity in a river system and for predicting the future trajectory of river health in response to external forcings. This paper documents the spatial morphological variability and its natural and anthropogenic controls for the Yamuna River, a major tributary of the Ganga River, India. The Yamuna River runs through a major urban centre i.e. Delhi National Capital Region. The Yamuna River was divided into eight geomorphically distinct reaches on the basis of the assemblages of geomorphic units and the association of landscape, valley and floodplain settings. The morphological variability was analysed through stream power distribution and sediment load data at various stations. Stream power distribution of the Yamuna River basin is characterised by a non-linear pattern that was used to distinguish (a) high energy ‘natural' upstream reaches, (b) ‘anthropogenically altered', low energy middle stream reaches, and (c) ‘rejuvenated' downstream reaches again with higher stream power. The relationship between stream power and channel morphology in these reaches was integrated with sediment load data to define the maximum flow efficiency (MFE) as the threshold for geomorphic transition. This analysis supports the continuity of river processes and the significance of a holistic, basin-scale approach rather than isolated local scale analysis in river studies.

  4. Water contamination and environmental ecosystem in the Harlem River

    Science.gov (United States)

    Wang, J.

    2013-12-01

    Nutrients, bacteria, polychlorinated biphenyls (PCBs) and other contaminates have degraded water quality of the Harlem River. The Harlem River is a natural straight connected to the Hudson River and the East River, and it has been used for navigation and boating. Water samples have been collected and analyzed from 2011 to 2013. Phosphorus, ammonia, turbidity, fecal coliform, E.Coli., and enterococcus all exceed regulated levels for New York City waters. There is only one wastewater treatment plant (Wards Island WWTP) that serves this river. Combined sewer overflows (CSOs) discharge raw sewage into the river during storms in spring and summer. Commercial fishing is banned, .however, individuals still fish. While some fishermen catch and release, it is likely some fish are consumed, creating concern for the environmental health of the community along the river. Storm water runoff, CSOs, and wastewater effluents are major pollutant sources of PCB 11 (3,3' dichlorobiphenyl), nutrient and bacteria. Nutrients, bacteria levels and their spatial/temporal variations were analyzed, and PCB analysis is underway. This data is a critical first step towards improving the water quality and environmental ecosystem in the Harlem River.

  5. Wild and Scenic Rivers

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This map layer portrays the linear federally-owned land features (i.e., national parkways, wild and scenic rivers, etc.) of the United States, Puerto Rico, and the...

  6. The Carmans River Story

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In this study, undertaken as an independent project at Bellport High School, the authors have attempted to provide a historical description of the Carmans River area...

  7. Management recommendations: Bear River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Bear River Migratory Bird Refuge, by a land use specialist. Recommendations, time frame and additional...

  8. River research programme

    CSIR Research Space (South Africa)

    Ferrar, AA

    1988-01-01

    Full Text Available The need for a comprehensive, multidisciplinary research programme for river ecosystems is described. The scope of the programme needs to include basic descriptions of a systems and biota, the testing and development of functional theory...

  9. Russian River Analysis

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is an analysis and summary of progress toward achieving the interim management objectives for the Russian River during the 1979 season. Additionally,...

  10. Features of anthropogenic changes in river hydrological parameters (for example Samara river.

    Directory of Open Access Journals (Sweden)

    Dovganenko D.A.

    2008-05-01

    Full Text Available Conducted attempt to analyze the nature of the mechanism of action of anthropogenic factors (in this case, mine water discharge to replace the water regime g. Samara. With typical river hydrographs built for the periods from 1952 to 1962 and from 1963 to 1975, revealed the instability of the spring floods, increased average long-term water consumption and increase the share of underground runoff. Approximately set the starting point changes the water regime of the river and found an association between increasing water inflow of mine water and increase average water discharge of Samara.

  11. The rivers of civilization

    Science.gov (United States)

    Macklin, Mark G.; Lewin, John

    2015-04-01

    The hydromorphic regimes that underpinned Old World river-based civilizations are reviewed in light of recent research. Notable Holocene climatic changes varied from region to region, whilst the dynamics of floodplain environments were equally diverse, with river channel changes significantly affecting human settlement. There were longer-term trends in Holocene hydroclimate and multi-centennial length 'flood-rich' and 'flood-poor' episodes. These impacted on five identified flooding and settlement scenarios: (i) alluvial fans and aprons; (ii) laterally mobile rivers; (iii) rivers with well-developed levees and flood basins; (iv) river systems characterised by avulsions and floodouts; and (v) large river-fed wetlands. This gave a range of changes that were either more or less regular or incremental from year-to-year (and thus potentially manageable) or catastrophic. The latter might be sudden during a flood event or a few seasons (acute), or over longer periods extending over many decades or even centuries (chronic). The geomorphic and environmental impacts of these events on riparian societies were very often irreversible. Contrasts are made between allogenic and autogenic mechanism for imposing environmental stress on riverine communities and a distinction is made between channel avulsion and contraction responses. Floods, droughts and river channel changes can precondition as well as trigger environmental crises and societal collapse. The Nile system currently offers the best set of independently dated Holocene fluvial and archaeological records, and the contrasted effects of changing hydromorphological regimes on floodwater farming are examined. The persistence of civilizations depended essentially on the societies that maintained them, but they were also understandably resilient in some environments (Pharaonic Egypt in the Egyptian Nile), appear to have had more limited windows of opportunity in others (the Kerma Kingdom in the Nubian Nile), or required

  12. Aquatic Habitat Studies on the Lower Mississippi River, River Mile 480 to 530. Report 5. Fish Studies--Pilot Report.

    Science.gov (United States)

    1981-05-01

    extends from river mile 499.1 to 499.7. b. A reach of natural bank extending from river mile 499.7 to 500.4. This section of bank was recently modified ...shiner, and river carp- sucker (Table 8). Cypress minnow, pugnose minnow, spotfin shiner, steel - color shiner, creek chub, and black buffalo were unique...Species Captured with Various Collecting Devices on 5-7 June 1978 from Lake Lee Gear* Species EG12 EG8 T122 T82 HN2 HN4 Paddlefish 7.4 12.5 3.4 Spotted

  13. Bull Trout Population Assessment in the White Salmon and Klickitat Rivers, Columbia River Gorge, Washington, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Thiesfeld, Steven L.; McPeak, Ronald H.; McNamara, Brian S. (Washington Department of Fish and Wildlife); Honanie, Isadore (Confederated Tribes and Bands, Yakama Nation)

    2002-01-01

    We utilized night snorkeling and single pass electroshocking to determine the presence or absence of bull trout Salvelinus confluentus in 26 stream reaches (3,415 m) in the White Salmon basin and in 71 stream reaches (9,005 m) in the Klickitat River basin during summer and fall 2001. We did not find any bull trout in the White Salmon River basin. In the Klickitat River basin, bull trout were found only in the West Fork Klickitat River drainage. We found bull trout in two streams not previously reported: Two Lakes Stream and an unnamed tributary to Fish Lake Stream (WRIA code number 30-0550). We attempted to capture downstream migrant bull trout in the West Fork Klickitat River by fishing a 1.5-m rotary screw trap at RM 4.3 from July 23 through October 17. Although we caught other salmonids, no bull trout were captured. The greatest limiting factor for bull trout in the West Fork Klickitat River is likely the small amount of available habitat resulting in a low total abundance, and the isolation of the population. Many of the streams are fragmented by natural falls, which are partial or complete barriers to upstream fish movement. To date, we have not been able to confirm that the occasional bull trout observed in the mainstem Klickitat River are migrating upstream into the West Fork Klickitat River.

  14. Matematica Natural.

    Science.gov (United States)

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…

  15. Framing nature

    NARCIS (Netherlands)

    Jansen, Peter

    2017-01-01

    This PhD thesis is about communication concerning nature in the Netherlands. The purpose of this exploratory study is to take both a theoretical and an empirical look at whether (implicit) religious elements play a role in this communication about nature in the Netherlands.   In this PhD thesis

  16. Natur formet

    DEFF Research Database (Denmark)

    Søberg, Martin

    2011-01-01

    Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011.......Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011....

  17. Hydrologic alteration affects aquatic plant assemblages in an arid-land river

    Science.gov (United States)

    Vinson, Mark; Hestmark, Bennett; Barkworth, Mary E.

    2014-01-01

    We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurrences of two macroalgae, Cladophora and Chara, and no submerged vascular plants were recorded in the Green and Yampa rivers. In 2009–2010, aquatic plants were abundant and widespread in the Green River from the dam downstream to the confluence with the Yampa River. The assemblage consisted of six vascular species, Elodea canadensis, Myriophyllum sibiricum, Nasturtium officinale,Potamogeton crispus, Potamogeton pectinatus, and Ranunculus aquatilis, the macroalgae Chara and Cladophora, and the bryophyte, Amblystegium riparium. In the Green River downstream from the Yampa River, and in the Yampa River, only sparse patches of Chara and Cladophora growing in the splash zone on boulders were collected. We attribute the observed changes in the Green River to an increase in water transparency and a reduction in suspended and bed-load sediment and high flow disturbances. The lack of hydrophyte colonization downstream from the confluence with the Yampa River has implications for understanding tributary amelioration of dam effects and for designing more natural flow-regime schedules downstream from large dams.

  18. Wind River Watershed Restoration: 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, Patrick J.

    2001-09-01

    This document represents work conducted as part of the Wind River Watershed Restoration Project during its first year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey--Columbia River Research Lab (USGS-CRRL), and WA Department of Fish & Wildlife (WDFW). Following categories given in the FY1999 Statement of Work, the broad categories, the related objectives, and the entities associated with each objective (lead entity in boldface) were as follows: Coordination--Objective 1: Coordinate the Wind River watershed Action Committee (AC) and Technical Advisory Committee (TAC) to develop a prioritized list of watershed enhancement projects. Monitoring--Objective 2: Monitor natural production of juvenile, smolt, and adult steelhead in the Wind River subbasin. Objective 3: Evaluate physical habitat conditions in the Wind River subbasin. Assessment--Objective 4: Assess watershed health using an ecosystem-based diagnostic model that will provide the technical basis to prioritize out-year restoration projects. Restoration--Objective 5: Reduce road related sediment sources by reducing road densities to less than 2 miles per square mile. Objective 6: Rehabilitate riparian corridors, flood plains, and channel morphology to reduce maximum water temperatures to less than 61 F, to increase bank stability to greater than 90%, to reduce bankfull width to depth ratios to less than 30, and to provide natural levels of pools and cover for fish. Objective 7: Maintain and evaluate passage for adult and juvenile steelhead at artificial barriers. Education

  19. River diversions, avulsions and captures in the Tortuguero coastal plain

    Science.gov (United States)

    Galve, Jorge Pedro; Alvarado, Guillermo; Pérez Peña, José Vicente; Azañón, José Miguel; Mora, Mauricio; Booth-Rea, Guillermo

    2016-04-01

    The Tortuguero area is a coastal plain that forms part of the North Limón sedimentary basin, the back-arc region of the Caribbean side of Costa Rica. This coastal plain is characterised by an abnormal drainage pattern with river captures, diversions and shifts in channel directions. We are analyzing this anomalous drainage network adopting a classical geomorphological approach combined with geomorphometric techniques. The SRTM DEM at 1 arc-second of resolution (~30 m) from NASA, topographic maps 1:50,000, satellital images and the digital cartography of the drainage network have been used for inventorying the channel pattern anomalies. River segments were categorized according to sinuosity, orientation, slope changes and incision using GIS tools. Initially, anomalies in the analyzed river courses suggested that buried thrust fronts could disrupt their natural pattern. However, we have not identified any evidence to link the activity of buried structures with the disruption of natural drainage. Blind thrusts detected through seismic subsurface exploration in the SE sector of the Tortuguero plain do not seem to produce changes in the sinuosity, orientation, slope and incision of rivers as those observed in the deeply studied tectonically active area of the Po Plain (Italy). The identified river pattern anomalies have been explained due to other alternative causes: (1) the migration of the mouths of Reventazón, Pacuare and Matina rivers is produced by sand sedimentation in the coast because of a successive ridge beach formation. This migration to the SE has the same direction than the main ocean currents those deposited the sand. (2) The anomalous course of Parismina river is most probably conditioned by the fracturation of the dissected volcanic apron of Turrialba volcano. (3) Channel migration and capture of Barbilla river by Matina river can be triggered by the tectonic tilting of the coastal plain towards the SE. The subsidence of the SE sector of the plain was

  20. Sustainable land and water management of River Oases along the Tarim River

    Directory of Open Access Journals (Sweden)

    M. Disse

    2016-05-01

    Full Text Available The Tarim Basin in Xinjiang province in northwest China is characterized by a hyper arid climate. Climate change and a strong increase in agricultural land use are major challenges for sustainable water management. The largest competition for water resources exists between irrigated fields and natural riparian vegetation, which is dependent on seasonal flooding of the Tarim River. In addition to numerous water management measures implemented by the Chinese government, the Sino-German project SuMaRiO (Sustainable Management of River Oases along the Tarim River provided a decision support system based on ecosystem services for the Chinese stakeholders. This tool will help to implement sustainable land and water management measures in the next 5-year plan.

  1. Modeling and analysis of horizontal structure of a mixed tree stands (on example of sample plots in the «Bastak» nature reserve in the Middle Amur river area

    Directory of Open Access Journals (Sweden)

    A. N. Kolobov

    2015-06-01

    Full Text Available The results of the research model and real data spatial distribution of trees in single-species, ages and mixed stands are studied. Modeling of the horizontal structure of the stand was based on a computer simulation model. Investigation of the horizontal structure of the stand allows drawing of conclusions about the processes of intraspecific and interspecific competition. It is shown that the model used to generate spatial data model reflects the basic mechanisms of stacked-mosaic structure of the stand, which is observed in natural communities. It allows future use of this model to study the characteristics of the formation of the spatial structure of mixed forest communities, developing under the influence of internal (competition and external (logging, windfalls, herbivores, etc. factors. Statistical analysis of the tree spatial distribution for shade-tolerant and light-loving species relative to each other showed that, on average, around an arbitrarily chosen shade-tolerant tree species, there is an area within which the opportunity to meet the tree light-loving species is less than it would be under their random placement. Around an arbitrarily chosen «large» tree of shade-tolerant species there is an area within which the opportunity to meet the «small» or «medium» light-loving tree species is less than would have been at their random placement. It is shown that the mutual arrangement of «large» light-loving trees and «small», «medium» shade-tolerant trees is no different from a random allocation. As a result of competitive processes of spatial arrangement for light-loving tree species is determined by the placement of shade-tolerant trees. Location of light-loving trees does not affect the location of shade-tolerant trees. The relative placement of different types of shade-tolerant trees, especially spruce, fir and pine, are independent of each other.

  2. Large Rivers in the Anthropocene: Insights and tools for understanding climatic, land use, and reservoir influences

    Science.gov (United States)

    Habersack, Helmut; Haspel, Daniel; Kondolf, Mathias

    2014-05-01

    Since the industrial revolution, human impacts on landscapes and river systems globally have intensified significantly. Humans nowadays artificially increase and decrease fluxes of water, sediment and nutrients on a scale far exceeding natural fluxes. Rivers integrate such changes occurring throughout their drainage basins, and thus can be considered as indicators of landscape processes and river basin "health" more broadly. This special issue brings together a set of papers that explore interactions of climate change and river processes, influences of land use changes, effects of reservoirs, as well as new approaches to sorting out the relative importance of these diverse influences on rivers and uncertainties in modeling future behavior. These papers contribute to a growing body of work demonstrating the fundamental differences between large rivers in the Anthropocene and rivers in prior time periods.

  3. Assessing geomorphic sensitivity in relation to river capacity for adjustment

    Science.gov (United States)

    Reid, H. E.; Brierley, G. J.

    2015-12-01

    River sensitivity describes the nature and rate of channel adjustments. An approach to analysis of geomorphic river sensitivity outlined in this paper relates potential sensitivity based on the expected capacity of adjustment for a river type to the recent history of channel adjustment. This approach was trialled to assess low, moderate and high geomorphic sensitivity for four different types of river (10 reaches in total) along the Lower Tongariro River, North Island, New Zealand. Building upon the River Styles framework, river types were differentiated based upon valley setting (width and confinement), channel planform, geomorphic unit assemblages and bed material size. From this, the behavioural regime and potential for adjustment (type and extent) were determined. Historical maps and aerial photographs were geo-rectified and the channel planform digitised to assess channel adjustments for each reach from 1928 to 2007. Floodplain width controlled by terraces, exerted a strong influence upon reach scale sensitivity for the partly-confined, wandering, cobble-bed river. Although forced boundaries occur infrequently, the width of the active channel zone is constrained. An unconfined braided river reach directly downstream of the terrace-confined section was the most geomorphically sensitive reach. The channel in this reach adjusted recurrently to sediment inputs that were flushed through more confined, better connected upstream reaches. A meandering, sand-bed river in downstream reaches has exhibited negligible rates of channel migration. However, channel narrowing in this reach and the associated delta indicate that the system is approaching a threshold condition, beyond which channel avulsion is likely to occur. As this would trigger more rapid migration, this reach is considered to be more geomorphically sensitive than analysis of its low migration rate alone would indicate. This demonstrates how sensitivity is fashioned both by the behavioural regime of a reach

  4. Dujiangyan: Could the ancient hydraulic engineering be a sustainable solution for Mississippi River diversions?

    Science.gov (United States)

    Xu, Y. J.

    2016-02-01

    Dujiangyan, also known as the Dujiangyan Project, is a hydraulic engineering complex built more than 2260 years ago on the Mingjiang River near Chengdu in China's Sichuan Province. The complex splits the river into two channels, a so-called "inner river" (Leijiang) and an "outer river" (Waijiang) that carry variable water volumes and sediment loads under different river flow conditions. The inner river and its numerous distributary canals are primarily man-made for irrigation over the past 2000 years, while the outer river is the natural channel and flows southward before entering into the Yangtze River. Under normal flow, 60% of the Mingjiang River goes into the inner river for irrigating nearly 1 million hectares of agricultural land on the Chengdu plain. During floods, however, less than 40% of the Mingjiang River flows into the inner river. Under both flow conditions, about 80% of the riverine sediments is carried by the outer river and continues downstream. This hydrology is achieved through a weir work complex that comprises three major components: a V-shaped bypass dike in the center of the Mingjiang River (the Yuzui Bypass Dike, see photo below), a sediment diversion canal in the inner river below the bypass dike (the Feishayan Floodgate), and a flow control in the inner river below the sediment diversion canal (the Baopingkou Diversion Passage). Together with ancillary embankments, these structures have not only ensured a regular supply of silt-reduced water to the fertile Chengdu plain, but have provided great benefits in flood control, sediment transport, and water resources regulation over the past two thousand years. The design of this ancient hydraulic complex ingeniously conforms to the natural environment while incorporating many sophisticated techniques, reflecting the concept that humankind is an integral part of nature. As we are urgently seeking solutions today to save the sinking Mississippi River Delta, examination of the ancient engineering

  5. Geomorphological approach to surficial material evaluation in the Serang River Basin Kulonprogo, Yogyakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Sutikno .

    2013-07-01

    Among landform units in the studied area which contains a large amount of the materials are: natural levees, river terraces, river bed and hill foot slopes. Generally, the river bed materials decrease in grain size downstreams and increase in sphericity and roundness coefficient. In some cross sections a reversal was found to the general tendency. This situation might be due to human activities for getting material for construction. Due to human activities some environmental impacts occur.

  6. Socio-economic Impacts on Flooding: A 4000-Year History of the Yellow River, China

    OpenAIRE

    Chen, Yunzhen; Syvitski, James P.M.; Gao, Shu; Overeem, Irina; Kettner, Albert J.

    2012-01-01

    We analyze 4000-year flood history of the lower Yellow River and the history of agricultural development in the middle river by investigating historical writings and quantitative time series data of environmental changes in the river basin. Flood dynamics are characterized by positive feedback loops, critical thresholds of natural processes, and abrupt transitions caused by socio-economic factors. Technological and organizational innovations were dominant driving forces of the flood history. ...

  7. Natural Propositions

    DEFF Research Database (Denmark)

    Stjernfelt, Frederik

    Preface -- Introduction -- The generality of signs -- Dicisigns -- Some consequences of the dicisign doctrine -- Dicisigns and cognition -- Natural propositions--the evolution of semiotic self-control -- Dicisigns beyond language -- Operational and optimal iconicity in Peirce's diagrammatology...

  8. Natural Communities

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset shows the locations of known tracts of high quality natural communities in Kansas, generalized to the PLSS section. It is not a compehensive dataset of...

  9. Writing Nature

    Directory of Open Access Journals (Sweden)

    Kristin Asdal

    2014-06-01

    Full Text Available This special issue of the Nordic Journal of Science and Technology Studies is interested in how nature, in different versions and forms, is invited into our studies, analyses, and stories. How is it that we “write nature”? How is it that we provide space for, and actually describe the actors, agents, or surroundings, in our stories and analyses? The articles in the issue each deal with different understandings of both the practices of writing and the introduction of various natures into these. In this introduction to the issue the editors engage with actor-network theory as a material semiotic resource for writing nature. We propose to foreground actor-network theory as a writing tool, at the expense of actor-network theory as a distinct vocabulary. In doing this and pointing out the semiotic origins to material-semiotics we also want to problematize a clear-cut material approach to writing nature.

  10. Hydrologic Variability of the Cosumnes River Floodplain

    Directory of Open Access Journals (Sweden)

    Eric Booth

    2006-09-01

    Full Text Available Natural floodplain ecosystems are adapted to highly variable hydrologic regimes, which include periodic droughts, infrequent large floods, and relatively frequent periods of inundation. To more effectively manage water resources and maintain ecosystem services provided by floodplains – and associated aquatic, riparian, and wetland habitats – requires an understanding of seasonal and inter-annual hydrologic variability of floodplains. The Cosumnes River, the largest river on the west-slope Sierra Nevada mountains without a major dam, provides a pertinent test case to develop a systematic classification of hydrologic variability. By examining the dynamics of its relatively natural flow regime, and a 98-year streamflow record (1908 – 2005, we identified 12 potential flood types. We identified four duration thresholds, defined as short (S, medium (M, long (L, and very long (V. We then intersected the flood duration division by three magnitude classes, defined as small-medium (1, large (2, and very large (3. Of the 12 possible flood types created by this classification matrix, the Cosumnes River streamflow record populated 10 such classes. To assess the robustness of our classification, we employed discriminant analysis to test class fidelity based on independent measures of flood capability, such as start date. Lastly, we used hierarchical divisive clustering to classify water years by flood type composition resulting in 8 water year types. The results of this work highlight the significant seasonal and inter-annual variability in natural flood regimes in Central Valley rivers. The construction of water impoundment and flood control structures has significantly altered all aspects of the flood pulse. Restoring floodplain ecosystem services will require re-establishing key elements of these historic flood regimes in order to achieve regional restoration goals and objectives.

  11. Second Nature

    OpenAIRE

    Skjonsberg, Matthew; Geuze, Adriaan

    2015-01-01

    The idea of virgin nature is more metaphor than reality – a metaphor best represented by the fabled garden paradise from which Homo sapiens’ ancient forebears were exiled. Despite the fact that virtually every development site borders on an existing city or infrastructure, and that billboards or industry are visible in every panorama, contemporary planning and modern architecture have stubbornly continued to cherish the illusion of a nature that is authentic. In an increasingly urbanized worl...

  12. Natural aphrodisiacs.

    Science.gov (United States)

    Shamloul, Rany

    2010-01-01

    The search for a remedy or a prescription that can enhance sexual function and/or treat male erectile dysfunction has been an obsession throughout known history. Whether it was an Eastern civilization or a Western one, religious or atheist, man's aspiration for a better or best "manhood" has been a history-time goal. This review will discuss the current research done on the most popular natural aphrodisiacs and examine the weight of evidence to support or discourage the use of any of these substances to enhance sexual desire and/or function. Review of the current evidence on the use of natural substances as aphrodisiacs. Efficacy of natural aphrodisiacs in enhancing sexual function in men and women. There is little evidence from literature to recommend the usage of natural aphrodisiacs for the enhancement of sexual desire and/or performance. Data on yohimbine's efficacy does not support the wide use of the drug, which has only mild effects in the treatment of psychogenic ED. Although there's a positive trend towards recommending ginseng as an effective aphrodisiac, however, more in depth studies involving large number of subjects and its mechanism of action are needed before definite conclusions could be reached. Data on the use of natural aphrodisiacs in women is limited. The current body of objective evidence does not support the use of any natural aphrodisiac as an effective treatment for male or female sexual dysfunctions. Potent men and men with ED will continue the search for natural aphrodisiacs despite the current disappointing data on their effectiveness. Care should be taken regarding the fraud addition of sildenafil analogues to natural aphrodisiacs.

  13. Wind River: A Wild and Scenic River Analysis: Preliminary draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Wind River meets the criteria for inclusion in the National Wild and Scenic Rivers System. Subject to valid existing rights, the minerals in Federal lands which...

  14. Heavy metal concentration of river sediment in the light of the environmental quality standard value of Japan from the river in and around the Tokyo Japan: A case study at the Tama, Tsurumi, Edo and Ara rivers

    Science.gov (United States)

    Watanabe, K.; Matsumoto, I.

    2008-12-01

    The river sediment is basically composed of clastic materials derived from the surface of the Earth. Purpose of our study is clarify the quantitative estimation of ratio of influence given to river sediment of nature and human activity by using of heavy metals. We show the geochemical and geological characteristics of stream sediments from the Tama, Tsurumi, Edo and Ara Rivers that flow in Tokyo bay, Japan. We show research results of the degree of contamination in above four rivers that are the relativery polluted river in Japan. Sediment samples collected from various points along the upper and lower streams were subjected to content analysis and elution analysis (using liquate (flow) out test) on the heavy metals like Cd, CN, Pb, Cr(6+), As and Hg from the river sediment for the purpose of environment assessment. Content of Cd, CN, Pb, Cr(6+), As, and Hg except Pb was above the environmental quality limit in few locations of the Tsurumi river. However, in the down-river part (mouth region) Pb-concentration was 10 times higher than at the source regions as the result of human impact; for Hg the same tendency was detected at the all rivers. This study is the first research that investigated river sediment in the light of the envirnomental quality standard in Tokyo area, Japan.

  15. The Colorado River

    Science.gov (United States)

    2002-01-01

    This Moderate-resolution Imaging Spectroradiometer (MODIS) true-color image shows the passage of the Colorado River through several southwestern states. The river begins, in this image, in Utah at the far upper right, where Lake Powell is visible as dark pixels surrounded by the salmon-colored rocks of the Colorado Plateau. The Colorado flows southwest through Glen Canyon, to the Glen Canyon Dam, on the Utah-Arizona border. From there it flows south into Arizona, and then turns sharply west where the Grand Canyon of the Colorado cuts through the mountains. The Colorado flows west to the Arizona-Nevada (upper left) border, where it is dammed again, this time by the Hoover Dam. The dark-colored pixels surrounding the bend in the river are Lake Mead. The river flows south along the border of first Nevada and Arizona and then California and Arizona. The Colorado River, which begins in Rocky Mountain National Park in Colorado, empties into the Gulf of California, seen at the bottom center of this image.

  16. Shoals and valley plugs in the Hatchie River watershed

    Science.gov (United States)

    Diehl, Timothy H.

    2000-01-01

    Agricultural land use and gully erosion have historically contributed more sediment to the streams of the Hatchie River watershed than those streams can carry. In 1970, the main sedimentation problem in the watershed occurred in the tributary flood plains. This problem motivated channelization projects (U.S. Department of Agriculture, 1970). By the mid-1980's, concern had shifted to sedimentation in the Hatchie River itself where channelized tributaries were understood to contribute much of the sediment. The Soil Conservation Service [Natural Resources Conservation Service (NRCS) since 1996] estimated that 640,000 tons of bedload (sand) accumulates in the Hatchie River each year and identified roughly the eastern two-thirds of the watershed, where loess is thin or absent, as the main source of sand (U.S. Department of Agriculture, 1986a). The U.S. Geological Survey (USGS), in cooperation with the West Tennessee River Basin Authority (WTRBA), conducted a study of sediment accumulation in the Hatchie River and its tributaries. This report identifies the types of tributaries and evaluates sediment, shoal formation, and valley-plug problems. The results presented here may contribute to a better understanding of similar problems in West Tennessee and the rest of the southeastern coastal plain. This information also will help the WTRBA manage sedimentation and erosion problems in the Hatchie River watershed.The source of the Mississippi section of the Hatchie River is in the sand hills southwest of Corinth, Mississippi (fig. 1). This section of the Hatchie River flows northward in an artificial drainage canal, gathering water from tributary streams that also are channelized. The drainage canal ends 2 miles south of the Tennessee State line. The Tennessee section of the Hatchie River winds north and west in a meandering natural channel to the Mississippi River. Although most of the Hatchie River tributaries are also drainage canals, the river's main stem has kept most of

  17. Flow dynamics at a river confluence on Mississippi River: field measurement and large eddy simulation

    Science.gov (United States)

    Le, Trung; Khosronejad, Ali; Bartelt, Nicole; Woldeamlak, Solomon; Peterson, Bonnie; Dewall, Petronella; Sotiropoulos, Fotis; Saint Anthony Falls Laboratory, University of Minnesota Team; Minnesota Department of Transportation Team

    2015-11-01

    We study the dynamics of a river confluence on Mississippi River branch in the city of Minneapolis, Minnesota, United States. Field measurements by Acoustic Doppler Current Profiler using on-board GPS tracking were carried out for five campaigns in the summer of 2014 and 2015 to collect both river bed elevation data and flow fields. Large Eddy Simulation is carried out to simulate the flow field with the total of 100 million grid points for the domain length of 3.2 km. The simulation results agree well with field measurements at measured cross-sections. The results show the existence of wake mode on the mixing interface of two branches near the upstream junction corner. The mutual interaction between the shear layers emanating from the river banks leading to the formation of large scale energetic structures that leads to ``switching'' side of the flow coherent structures. Our result here is a feasibility study for the use of eddy-resolving simulations in predicting complex flow dynamics in medium-size natural rivers. This work is funded by Minnesota Dept. Transportation and Minnesota Institute of Supercomputing.

  18. Assessing flow regime alterations in a temporary river – the River Celone case study

    Directory of Open Access Journals (Sweden)

    De Girolamo Anna Maria

    2015-09-01

    Full Text Available In this paper, we present an approach to evaluate the hydrological alterations of a temporary river. In these rivers, it is expected that anthropogenic pressures largely modify low-flow components of the flow regime with consequences for aquatic habitat and diversity in invertebrate species. First, by using a simple hydrological index (IARI river segments of the Celone stream (southern Italy whose hydrological regime is significantly influenced by anthropogenic activities have been identified. Hydrological alteration has been further classified through the analysis of two metrics: the degree (Mf and the predictability of dry flow conditions (Sd6. Measured streamflow data were used to calculate the metrics in present conditions (impacted. Given the lack of data from pristine conditions, simulated streamflow time series were used to calculate the metrics in reference conditions. The Soil and Water Assessment Tool (SWAT model was used to estimate daily natural streamflow. Hydrological alterations associated with water abstractions, point discharges and the presence of a reservoir were assessed by comparing the metrics (Mf, Sd6 before and after the impacts. The results show that the hydrological regime of the river segment located in the upper part of the basin is slightly altered, while the regime of the river segment downstream of the reservoir is heavily altered. This approach is intended for use with ecological metrics in defining the water quality status and in planning streamflow management activities.

  19. 50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook...

  20. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take care...

  1. Human impacts on river ice regime in the Carpathian Basin

    Science.gov (United States)

    Takács, Katalin; Nagy, Balázs; Kern, Zoltán

    2014-05-01

    River ice is a very important component of the cryosphere, and is especially sensitive to climatic variability. Historical records of appearance or disappearance and timing of ice phenomena are useful indicators for past climatic variations (Williams, 1970). Long-term observations of river ice freeze-up and break-up dates are available for many rivers in the temperate or cold region to detect and analyze the effects of climate change on river ice regime. The ice regime of natural rivers is influenced by climatic, hydrological and morphological factors. Regular ice phenomena observation mostly dates back to the 19th century. During this long-term observation period, the human interventions affecting the hydrological and morphological factors have become more and more intensive (Beltaos and Prowse, 2009). The anthropogenic effects, such as river regulation, hydropower use or water pollution causes different changes in river ice regime (Ashton, 1986). To decrease the occurrence of floods and control the water discharge, nowadays most of the rivers are regulated. River regulation changes the morphological parameters of the river bed: the aim is to create solid and equable bed size and stream gradient to prevent river ice congestion. For the satisfaction of increasing water demands hydropower is also used. River damming results a condition like a lake upstream to the barrage; the flow velocity and the turbulence are low, so this might be favourable for river ice appearance and freeze-up (Starosolsky, 1990). Water pollution affects ice regime in two ways; certain water contaminants change the physical characteristics of the water, e.g. lessens the freezing point of the water. Moreover the thermal stress effect of industrial cooling water and communal wastewater is also important; in winter these water sources are usually warmer, than the water body of the river. These interventions result different changes in the characteristic features of river ice regime. Selected

  2. Covalent binding of aniline to humic substances. 1. Kinetic studies

    Science.gov (United States)

    Weber, E.J.; Spidle, D.L.; Thorn, K.A.

    1996-01-01

    The reaction kinetics for the covalent binding of aniline with reconstituted IHSS humic and fulvic acids, unfractionated DOM isolated from Suwannee River water, and whole samples of Suwannee River water have been investigated. The reaction kinetics in each of these systems can be adequately described by a simple second-order rate expression. The effect of varying the initial concentration of aniline on reaction kinetics suggested that approximately 10% of the covalent binding sites associated with Suwannee River fulvic acid are highly reactive sites that are quickly saturated. Based on the kinetic parameters determined for the binding of aniline with the Suwannee River fulvic and humic acid isolates, it was estimated that 50% of the aniline concentration decrease in a Suwannee River water sample could be attributed to reaction with the fulvic and humic acid components of the whole water sample. Studies with Suwannee River fulvic acid demonstrated that the rate of binding decreased with decreasing pH, which parallels the decrease in the effective concentration of the neutral form, or reactive nucleophilic species of aniline. The covalent binding of aniline with Suwannee River fulvic acid was inhibited by prior treatment of the fulvic acid with hydrogen sulfide, sodium borohydride, or hydroxylamine. These observations are consistent with a reaction pathway involving nucleophilic addition of aniline to carbonyl moieties present in the fulvic acid.

  3. The Management of Dissonance in Nature Restoration

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2016-01-01

    Nature restoration is far from a neural undertaking. Just like any other type of heritage production, it can be the source of dissonance—‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particularly sensitive to site-specificity. As exemplified...... for multiple interpretations to coexist. Indications can be found in the Re-naturalization of River Aire (2002-2015)—a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  4. The Management of Dissonance in Nature Restoration

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    Nature restoration is far from a neural undertaking. Just like any other type of heritage production, it can be the source of dissonance—‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particularly sensitive to site-specificity. As exemplified...... for multiple interpretations to coexist. Indications can be found in the Re-naturalization of River Aire (2002-2015)—a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  5. 33 CFR 117.734 - Navesink River (Swimming River).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming R