Challenges to reestablishment of free-ranging populations of black-footed ferrets
E. Biggins, Jerry L. Godbey
2003, Comptes Rendus - Biologies (326) 104-111
The black-footed ferret (Mustela nigripes) of North America is critically endangered due in part to its extreme specialization on formerly stable and abundant prairie dogs (Cynomys). Its close relative, the Siberian polecat (M. eversmannii) seems to have been subjected to a varying environment that was not conducive to specialization. One source of environmental variation in Asian steppes was...
Modeling Np and Pu transport with a surface complexation model and spatially variant sorption capacities: Implications for reactive transport modeling and performance assessments of nuclear waste disposal sites
P. D. Glynn
2003, Computers & Geosciences (29) 331-349
One-dimensional (1D) geochemical transport modeling is used to demonstrate the effects of speciation and sorption reactions on the ground-water transport of Np and Pu, two redox-sensitive elements. Earlier 1D simulations (Reardon, 1981) considered the kinetically limited dissolution of calcite and its effect on ion-exchange reactions (involving 90Sr, Ca, Na, Mg and...
Arsenic in groundwater in eastern New England: Occurrence, controls, and human health implications
J. D. Ayotte, D.L. Montgomery, S. M. Flanagan, K. W. Robinson
2003, Environmental Science & Technology (37) 2075-2083
In eastern New England, high concentrations (greater than 10 ??g/L) of arsenic occur in groundwater. Privately supplied drinking water from bedrock aquifers often has arsenic concentrations at levels of concern to human health, whereas drinking water from unconsolidated aquifers is least affected by arsenic contamination. Water from wells in metasedimentary...
The effects of ultraviolet-B radiation on the toxicity of fire-fighting chemicals
R.D. Calfee, E. E. Little
2003, Environmental Toxicology and Chemistry (22) 1525-1531
The interactive effects of ultraviolet (UV) and fire-retardant chemicals were evaluated by exposing rainbow trout (Oncorhyncus mykiss) juveniles and tadpoles of southern leopard frogs (Rana sphenocephala) to six fire-retardant formulations with and without sodium ferrocyanide (yellow prussiate of soda [YPS]) and to YPS alone under three simulated UV light treatments....
Effects of flooding on abundance of native and nonnative fishes downstream from a small impoundment
A.A. Schultz, O.E. Maughan, Scott A. Bonar, W.J. Matter
2003, North American Journal of Fisheries Management (23) 503-511
Flooding can benefit native fishes in southwestern streams by disproportionately displacing nonnative fishes. We examined how the presence of an upstream impoundment affected this relationship in lower Sonoita Creek, Arizona. Nonnative species not found in the reservoir decreased in abundance in lower Sonoita Creek after flooding. The catch and relative...
Empirical ground-motion relations for subduction-zone earthquakes and their application to Cascadia and other regions
G. M. Atkinson, D.M. Boore
2003, Bulletin of the Seismological Society of America (93) 1703-1729
Ground-motion relations for earthquakes that occur in subduction zones are an important input to seismic-hazard analyses in many parts of the world. In the Cascadia region (Washington, Oregon, northern California, and British Columbia), for example, there is a significant hazard from megathrust earthquakes along the subduction interface and from large...
Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data
J.E. Ebel, D.J. Wald
2003, Earthquake Spectra (19) 511-529
We describe a new probabilistic method that uses observations of modified Mercalli intensity (MMI) from past earthquakes to make quantitative estimates of ground shaking parameters (i.e., peak ground acceleration, peak ground velocity, 5% damped spectral acceleration values, etc.). The method uses a Bayesian approach to make quantitative estimates of the...
Sequestration of phosphorus by acid mine drainage floc
P.R. Adler, P.L. Sibrell
2003, Journal of Environmental Quality (32) 1122-1129
Solubilization and transport of phosphorus (P) to the water environment is a critical environmental issue. Flocs resulting from neutralizing acid mine drainage (AMD) were tested as a possible low-cost amendment to reduce the loss of soluble P from agricultural fields and animal wastewater. Flocs were prepared by neutralizing natural and...
Role of debris flows in long-term landscape denudation in the central Appalachians of Virginia
L.S. Eaton, B. A. Morgan, R.C. Kochel, A.D. Howard
2003, Geology (31) 339-342
Four major storms that triggered debris flows in the Virginia-West Virginia Appalachians provide new insights into the role of high-magnitude, low-frequency floods in long-term denudation and landscape evolution in mountainous terrain. Storm denudation in the Blue Ridge Mountain drainage basins in approximately an order of magnitude greater compared to basins...
Seismic velocity anisotropy and heterogeneity beneath the Mantle Electromagnetic and Tomography Experiment (MELT) region of the East Pacific Rise from analysis of P and S body waves
W.C. Hammond, D.R. Toomey
2003, Journal of Geophysical Research B: Solid Earth (108)
We use teleseismic P and S delay times and shear wave splitting measurements to constrain isotropic and anisotropic heterogeneity in the mantle beneath the southern East Pacific Rise (SEPR). The data comprise 462 P and S delay times and 18 shear wave splitting observations recorded during the Mantle Electromagnetic and...
Effects of electrofishing gear type on spatial and temporal variability in fish community sampling
M. R. Meador, J.P. McIntyre
2003, Transactions of the American Fisheries Society (132) 709-716
Fish community data collected from 24 major river basins between 1993 and 1998 as part of the U.S. Geological Survey's National Water-Quality Assessment Program were analyzed to assess multiple-reach (three consecutive reaches) and multiple-year (three consecutive years) variability in samples collected at a site. Variability was assessed using the coefficient...
Magnitude and variability of Holocene sediment accumulation in Santa Monica Bay, California
C.K. Sommerfield, H.J. Lee
2003, Marine Environmental Research (56) 151-176
The spatial variability of Holocene (past 10,000 years) sediment accumulation in Santa Monica Bay (California) was examined to identify controls sediment trapping in a bathymetrically complex coastal embayment and to provide geologic context for the post-industrial sedimentary record and associated pollution gradients. Sediment chronologies based on downcore AMS 14C dates...
The strength and rheology of methane clathrate hydrate
W.B. Durham, S. H. Kirby, L.A. Stern, W. Zhang
2003, Journal of Geophysical Research B: Solid Earth (108)
Methane clathrate hydrate (structure I) is found to be very strong, based on laboratory triaxial deformation experiments we have carried out on samples of synthetic, high-purity, polycrystalline material. Samples were deformed in compressional creep tests (i.e., constant applied stress, ??), at conditions of confining pressure P = 50 and 100...
Impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon
D.D. Dauble, T.P. Hanrahan, D.R. Geist, M.J. Parsley
2003, North American Journal of Fisheries Management (23) 641-659
Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake...
An empirical approach to inversion of an unconventional helicopter electromagnetic dataset
L. Pellerin, V.F. Labson
2003, Journal of Applied Geophysics (53) 49-61
A helicopter electromagnetic (HEM) survey acquired at the U.S. Idaho National Engineering and Environmental Laboratory (INEEL) used a modification of a traditional mining airborne method flown at low levels for detailed characterization of shallow waste sites. The low sensor height, used to increase resolution, invalidates standard assumptions used in processing...
Pore space analysis of NAPL distribution in sand-clay media
D. Matmon, N.J. Hayden
2003, Advances in Water Resources (26) 773-785
This paper introduces a conceptual model of clays and non-aqueous phase liquids (NAPLs) at the pore scale that has been developed from a mathematical unit cell model, and direct micromodel observation and measurement of clay-containing porous media. The mathematical model uses a unit cell concept with uniform spherical grains for...
Timing of recent accelerations of Pine Island Glacier, Antarctica
I. Joughin, Eric Rignot, Christine E. Rosanova, Baerbel K. Lucchitta, J. Bohlander
2003, Geophysical Research Letters (30)
We have used Interferometric Synthetic Aperture Radar (InSAR) data and sequential Landsat imagery to identify and temporally constrain two acceleration events on Pine Island Glacier (PIG). These two events are separated by a period of at least seven years (1987 - 1994). The change in discharge between two flux gates...
Comparison of migration rate and survival between radio-tagged and PIT-tagged migrant yearling chinook salmon in the Snake and Columbia rivers
E.E. Hockersmith, W.D. Muir, S.G. Smith, B.P. Sandford, R.W. Perry, N.S. Adams, D.W. Rondorf
2003, North American Journal of Fisheries Management (23) 404-413
A study was conducted to compare the travel times, detection probabilities, and survival of migrant hatchery-reared yearling chinook salmon Oncorhynchus tshawytscha tagged with either gastrically or surgically implanted sham radio tags (with an imbedded passive integrated transponder [PIT] tag) with those of their cohorts tagged only with PIT tags in...
Comparison of P- and S-wave velocity profiles obtained from surface seismic refraction/reflection and downhole data
R. A. Williams, W. J. Stephenson, J. K. Odum
2003, Tectonophysics (368) 71-88
High-resolution seismic-reflection/refraction data were acquired on the ground surface at six locations to compare with near-surface seismic-velocity downhole measurements. Measurement sites were in Seattle, WA, the San Francisco Bay Area, CA, and the San Fernando Valley, CA. We quantitatively compared the data in terms of the average shear-wave velocity to...
Genetic variation in black bears in Arkansas and Louisiana using microsatellite DNA markers
Ildiki Csiki, Cynthia Lam, Audie Key, Erica Coulter, Joseph D. Clark, Richard M. Pace III, Kimberly G. Smith, Douglas D. Rhoads
2003, Journal of Mammalogy (84) 691-701
In the 1950s and 1960s, translocation projects reintroduced black bears (Ursus americanus) from Minnesota and Manitoba to Arkansas and Louisiana. Today, several geographically disconnected populations exist in Arkansas and Louisiana, but their origins are unclear. Some populations may represent a separate subspecies, U. a. luteolus, which is federally protected. We characterized...
Modeling flow and transport in unsaturated fractured rock: An evaluation of the continuum approach
H.-H. Liu, C.B. Haukwa, C.F. Ahlers, G.S. Bodvarsson, A. L. Flint, W.B. Guertal
2003, Journal of Contaminant Hydrology (62-63) 173-188
Because the continuum approach is relatively simple and straightforward to implement, it has been commonly used in modeling flow and transport in unsaturated fractured rock. However, the usefulness of this approach can be questioned in terms of its adequacy for representing fingering flow and transport in unsaturated fractured rock. The...
Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska
Robert T. Ourso, S.A. Frenzel
2003, Hydrobiologia (501) 117-131
We examined biotic and physiochemical responses in urbanized Anchorage, Alaska, to the percent of impervious area within stream basins, as determined by high-resolution IKONOS satellite imagery and aerial photography. Eighteen of the 86 variables examined, including riparian and instream habitat, macroinvertebrate communities, and water/sediment chemistry, were significantly correlated with percent...
Geographic information systems and spatial analysis of adult Ixodes scapularis (Acari: Ixodidae) in the Middle Atlantic region of the U.S.A
J.E. Bunnell, S. D. Price, A. Das, T.M. Shields, G.E. Glass
2003, Journal of Medical Entomology (40) 570-576
In the Middle Atlantic region of the U.S.A., the vector of Lyme disease, human granulocytic ehrlichiosis, babesiosis, and other human and veterinary pathogens is the black-legged tick, Ixodes scapularis Say. In 1997 and 1998, 663 adult I. scapularis ticks were collected from 320 transects spanning 66,400 km2 in five states...
Hilbert-Huang transform analysis of dynamic and earthquake motion recordings
R.R. Zhang, S. Ma, E. Safak, S. Hartzell
2003, Journal of Engineering Mechanics (129) 861-875
This study examines the rationale of Hilbert-Huang transform (HHT) for analyzing dynamic and earthquake motion recordings in studies of seismology and engineering. In particular, this paper first provides the fundamentals of the HHT method, which consist of the empirical mode decomposition (EMD) and the Hilbert spectral analysis. It then uses...
Estimating cougar predation rates from GPS location clusters
C.R. Anderson Jr., F.G. Lindzey
2003, Journal of Wildlife Management (67) 307-316
We examined cougar (Puma concolor) predation from Global Positioning System (GPS) location clusters (???2 locations within 200 m on the same or consecutive nights) of 11 cougars during September-May, 1999-2001. Location success of GPS averaged 2.4-5.0 of 6 location attempts/night/cougar. We surveyed potential predation sites during summer-fall 2000 and summer...
