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Page 981, results 24501 - 24525

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Not all publications have extents, not all extents are completely accurate
Three-dimensional geophysical mapping of rock alteration and water content at Mount Adams, Washington: Implications for lahar hazards
C. A. Finn, M. Deszcz-Pan, E. D. Anderson, D. A. John
2007, Journal of Geophysical Research B: Solid Earth (112)
[1] Hydrothermally altered rocks, particularly if water saturated, can weaken stratovolcanoes, thereby increasing the potential for catastrophic sector collapses that can lead to far-traveled, destructive debris flows. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes...
Bypass system modification at Bonneville Dam on the Columbia River improved the survival of juvenile salmon
J.W. Ferguson, B.P. Sandford, R.E. Reagan, L.G. Gilbreath, E.B. Meyer, R.D. Ledgerwood, N.S. Adams
2007, Transactions of the American Fisheries Society (136) 1487-1510
From 1987 to 1992, we evaluated a fish bypass system at Bonneville Dam Powerhouse 2 on the Columbia River. The survival of subyearling Chinook salmon Oncorhynchus tshawytscha released into the system ranged from 0.774 to 0.911 and was significantly lower than the survival of test fish released into turbines and...
Use of a watershed model to characterize the fate and transport of fluometuron, a soil-applied cotton herbicide, in surface water
R.H. Coupe
2007, International Journal of Environmental Analytical Chemistry (87) 883-896
The Soil and Water Assessment Tool (SWAT) was used to characterize the fate and transport of fluometuron (a herbicide used on cotton) in the Bogue Phalia Basin in northwestern Mississippi, USA. SWAT is a basin-scale watershed model, able to simulate hydrological, chemical, and sediment transport processes. After adjustments to a...
Crossing disciplines and scales to understand the critical zone
S.L. Brantley, M. B. Goldhaber, Ragnarsdottir K. Vala
2007, Elements (3) 307-314
The Critical Zone (CZ) is the system of coupled chemical, biological, physical, and geological processes operating together to support life at the Earth's surface. While our understanding of this zone has increased over the last hundred years, further advance requires scientists to cross disciplines and scales to integrate understanding of...
An innovative carbonate coprecipitation process for the removal of zinc and manganese from mining impacted waters
P.L. Sibrell, M.A. Chambers, A.L. Deaguero, T.R. Wildeman, D.J. Reisman
2007, Environmental Engineering Science (24) 881-895
Although mine drainage is usually thought of as acidic, there are many cases where the water is of neutral pH, but still contains metal species that can be harmful to human or aquatic animal health, such as manganese (Mn) and zinc (Zn). Typical treatment of mine drainage waters involves pH...
Dust emission from wet and dry playas in the Mojave Desert, USA
Richard L. Reynolds, James C. Yount, Marith C. Reheis, Harland L. Goldstein, Pat F. Chavez Jr., Robert E. Fulton, John W. Whitney, Christopher C. Fuller, Richard M. Forester
2007, Earth Surface Processes and Landforms (32) 1811-1827
The interactions between playa hydrology and playa-surface sediments are important factors that control the type and amount of dust emitted from playas as a result of wind erosion. The production of evaporite minerals during evaporative loss of near-surface ground water results in both the creation and maintenance of several centimeters...
Methane-derived authigenic carbonates from the northern Gulf of Mexico - MD02 Cruise
Y. Chen, R. Matsumoto, C. K. Paull, W. Ussler III, T. Lorenson, P. Hart, W. Winters
2007, Journal of Geochemical Exploration (95) 1-15
Authigenic carbonates were sampled in piston cores collected from both the Tunica Mound and the Mississippi Canyon area on the continental slope of the northern Gulf of Mexico during a Marion Dufresne cruise in July 2002. The carbonates are present as hardgrounds, porous crusts, concretions or nodules and shell fragments with or...
Role of aquifer heterogeneity in fresh groundwater discharge and seawater recycling: An example from the Carmel coast, Israel
Y. Weinstein, W. C. Burnett, P.W. Swarzenski, Y. Shalem, Y. Yechieli, B. Herut
2007, Journal of Geophysical Research C: Oceans (112)
A case study is shown in which the pattern of submarine groundwater discharge and of seawater recycling is controlled by local hydrogeological variability. The coastal aquifer in Dor Bay is composed of two units: a partly confined calcaranitic sandstone (Kurkar) and an overlying loose sand. Groundwater in the Kurkar has...
MODIS imagery as a tool for synoptic water quality assessments in the southern California coastal ocean
N.P. Nezlin, P.M. DiGiacomo, B.H. Jones, K.M. Reifel, J.A. Warrick, S.C. Johnson, M.J. Mengel
2007, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The dynamics of rainstorm plumes in the coastal waters of southern California was studied during the Bight'03 Regional Water Quality Program surveys. Measurements of surface salinity and bacterial counts collected from research vessels were compared to MODIS-Aqua satellite imagery. The spectra of normalized water-leaving radiation (nLw) were different in plumes...
Spatial distribution of juvenile and adult female Tanner crabs (Chionoecetes bairdi) in a glacial fjord ecosystem: Implications for recruitment processes
J.K. Nielsen, S. James Taggart, Thomas C. Shirley, Jennifer Mondragon
2007, ICES Journal of Marine Science (64) 1772-1784
A systematic pot survey in Glacier Bay, Alaska, was conducted to characterize the spatial distribution of juvenile and adult female Tanner crabs, and their association with depth and temperature. The information was used to infer important recruitment processes for Tanner crabs in glaciated ecosystems. High-catch areas for juvenile and adult...
Restoration of waterbird habitats in Chesapeake Bay: Great expectations or Sisyphus revisited?
R.M. Erwin, R.A. Beck
2007, Waterbirds (30) 163-176
In the past half century, many waterbird populations in Chesapeake Bay have declined or shifted ranges, indicating major ecological changes have occurred. While many studies have focused on the problems associated with environmental degradation such as the losses of coastal wetlands and submerged vegetation, a number of restoration efforts have...
Genetic variability in spotted seatrout (Cynoscion nebulosus), determined with microsatellite DNA markers
R. Ward, K. Bowers, R. Hensley, B. Mobley, E. Belouski
2007, Fishery Bulletin (105) 197-206
Variation in the allele frequencies of five microsatellite loci was surveyed in 1256 individual spotted seatrout (Cynoscion nebulosus) obtained from 12 bays and estuaries from Laguna Madre, Texas, to Charlotte Harbor, Florida, to St. John's River on the Florida Atlantic Coast. Texas and Louisiana collection sites were resampled each year...
Hydrogeologic controls on nitrate transport in a small agricultural catchment, Iowa
K. E. Schilling, M.D. Tomer, Y.-K. Zhang, T. Weisbrod, P. Jacobson, C.A. Cambardella
2007, Journal of Geophysical Research G: Biogeosciences (112)
Effects of subsurface deposits on nitrate loss in stream riparian zones are recognized, but little attention has been focused on similar processes occurring in upland agricultural settings. In this paper, we evaluated hydrogeologic controls on nitrate transport processes occurring in a small 7.6 ha Iowa catchment. Subsurface deposits in the...
Evidence of widespread natural reproduction by lake trout Salvelinus namaycush in the Michigan waters of Lake Huron
S.C. Riley, J.X. He, J.E. Johnson, T. P. O’Brien, J.S. Schaeffer
2007, Journal of Great Lakes Research (33) 917-921
Localized natural reproduction of lake trout Salvelinus namaycush in Lake Huron has occurred since the 1980s near Thunder Bay, Michigan. During 2004–2006, USGS spring and fall bottom trawl surveys captured 63 wild juvenile lake trout at depths ranging from 37–73 m at four of five ports in the Michigan waters of the...
Geochemistry of natural components in the near-field environment, Yucca Mountain, Nevada
Z. E. Peterman, T.A. Oliver
2007, Conference Paper, Materials Research Society Symposium Proceedings
The natural near-field environment in and around the emplacement drifts of the proposed nuclear waste repository at Yucca Mountain, Nevada, includes the host rock, dust, seepage, and pore water. The chemical compositions of these components have been determined for assessing possible chemical and mineralogical reactions that may occur after nuclear...
Toward a transport-based analysis of nutrient spiraling and uptake in streams
Robert L. Runkel
2007, Limnology and Oceanography: Methods (5) 50-62
Nutrient addition experiments are designed to study the cycling of nutrients in stream ecosystems where hydrologic and nonhydrologic processes determine nutrient fate. Because of the importance of hydrologic processes in stream ecosystems, a conceptual model known as nutrient spiraling is frequently employed. A central part of the nutrient spiraling approach...
The geology of asbestos in the United States and its practical applications
B. S. Van Gosen
2007, Environmental & Engineering Geoscience (13) 55-68
Recently, naturally occurring asbestos (NOA) has drawn the attention of numerous health and regulatory agencies and citizen groups. NOA can be released airborne by (1) the disturbance of asbestos-bearing bedrocks through human activities or natural weathering, and (2) the mining and milling of some mineral deposits in which asbestos occurs...
Mercury and trace elements in crayfish from northern California
R. L. Hothem, D.R. Bergen, M.L. Bauer, J.J. Crayon, A.M. Meckstroth
2007, Bulletin of Environmental Contamination and Toxicology (79) 628-632
We collected two species of crayfish, Pacifastacus leniusculus and Procambarus clarkii, from Cache and Putah Creeks, California, and analyzed them for mercury and trace elements. Trace elements were higher in carcasses in 40 cases, higher in tails in 5 cases, and not different in 35 cases; no concentration exceeded levels...
Magnesium and calcium sulfate stabilities and the water budget of Mars
I.-M. Chou, R.R. Seal II
2007, Journal of Geophysical Research E: Planets (112)
Magnesium sulfate probably plays a dominant role in the water cycle of Mars away from the polar ice caps through hydration and dehydration reactions. This prominence is due to its abundance, its occurrence in numerous hydration states, and its ability to hydrate and dehydrate rapidly. New experimental studies on the...
Fate and groundwater impacts of produced water releases at OSPER "B" site, Osage County, Oklahoma
Yousif K. Kharaka, E. Kakouros, James J. Thordsen, Gil Ambats, Marvin M. Abbott
2007, Applied Geochemistry (22) 2164-2176
For the last 5 a, the authors have been investigating the transport, fate, natural attenuation and ecosystem impacts of inorganic and organic compounds in releases of produced water and associated hydrocarbons at the Osage-Skiatook Petroleum Environmental Research (OSPER) “A” and “B” sites,...
Diurnal variability in riverine dissolved organic matter composition determined by in situ optical measurement in the San Joaquin River (California, USA)
R.G.M. Spencer, B.A. Pellerin, B.A. Bergamaschi, B.D. Downing, T.E.C. Kraus, D.R. Smart, R.A. Dahlgren, P.J. Hernes
2007, Hydrological Processes (21) 3181-3189
Dissolved organic matter (DOM) concentration and composition in riverine and stream systems are known to vary with hydrological and productivity cycles over the annual and interannual time scales. Rivers are commonly perceived as homogeneous with respect to DOM concentration and composition, particularly under steady flow conditions over short time periods....
Large fluctuations of dissolved oxygen in the Indian and Pacific oceans during Dansgaard-Oeschger oscillations caused by variations of North Atlantic Deep Water subduction
A. Schmittner, E.D. Galbraith, S. W. Hostetler, Thomas F. Pedersen, R. Zhang
2007, Paleoceanography (22)
Paleoclimate records from glacial Indian and Pacific oceans sediments document millennial-scale fluctuations of subsurface dissolved oxygen levels and denitrification coherent with North Atlantic temperature oscillations. Yet the mechanism of this teleconnection between the remote ocean basins remains elusive. Here we present model simulations of the oxygen and nitrogen cycles that...
Distribution and abundance of burrowing mayflies (Hexagenia spp.) in Lake Erie, 1997-2005
K.A. Krieger, M.T. Bur, J.J.H. Ciborowski, D.R. Barton, D. W. Schloesser
2007, Journal of Great Lakes Research (33) 20-33
Burrowing mayflies (Hexagenia limbata and H. rigida) recolonized sediments of the western basin of Lake Erie in the 1990s following decades of pollution abatement. We predicted that Hexageniawould also disperse eastward or expand from existing localized populations and colonize large regions of the other basins. We sampled zoobenthos in parts of the western...
Evaluation of sulfate reduction at experimentally induced mixing interfaces using small-scale push-pull tests in an aquifer-wetland system
T.A. Kneeshaw, Jennifer T. McGuire, Erik W. Smith, Isabelle M. Cozzarelli
2007, Applied Geochemistry (22) 2618-2629
This paper presents small-scale push–pull tests designed to evaluate the kinetic controls on SO42-">SO42- reduction in situ at mixing interfaces between a wetland and aquifer impacted by landfill leachate at the Norman Landfill research site, Norman, OK. Quantifying the...