Etologia aplicada al manejo de especies amenazadas: el caso del turon de patas negras (Mustela nigripes)
Astrid Vargas, D. Biggins, B. Miller
1999, Etologia 33-39
Los turones de patas negras (Mustela nigripes) son considerados como uno de los mamíferos más amenazados del mundo. La última población silvestre fue descubierta en 1981 en Meeteetse, Wyoming, y en 1985 se extinguió debido a una epidemia de moquillo canino en combinacion con una epidemia de peste bubónica. Antes de...
Calcium ion binding to a soil fulvic acid using a donnan potential model
J.A. Marinsky, A. Mathuthu, J.H. Ephraim, M.M. Reddy
1999, Radiochimica Acta (84) 205-211
Calcium ion binding to a soil fulvic acid (Armadale Bh Horizon) was evaluated over a range of calcium ion concentrations, from pH 3.8 to 7.3, using potentiometric titrations and calcium ion electrode measurements. Fulvic acid concentration was constant (100 milligrams per liter) and calcium ion concentration varied up to 8...
Observations of turbulence in a partially stratified estuary
M.T. Stagey, Stephen G. Monismith, J.R. Burau
1999, Journal of Physical Oceanography (29) 1950-1970
The authors present a field study of estuarine turbulence in which profiles of Reynolds stresses were directly measured using an ADCP throughout a 25-h tidal day. The dataset that is discussed quantifies turbulent mixing for a water column in northern San Francisco Bay that experiences a sequence of states that...
Chlorine-bearing amphiboles from the Fraser mine, Sudbury, Ontario, Canada: Description and crystal chemistry
K.A. McCormick, A.M. McDonald
1999, Canadian Mineralogist (37) 1385-1403
Three chemically distinct populations of Cl-bearing amphibole have been recognized in association with contact Ni-Cu ore deposits in Footwall Breccia at the Fraser mine, Sudbury, Ontario. The first population, defined as halogen-poor (<0.5 wt.% Cl) actinolite and magnesiohornblende, occurs predominantly as pale green grains and cores. These are generally overgrown...
Simulation of methyl tert-butyl ether (MTBE) transport to ground water from immobile sources of gasoline in the vadose zone
M.A. Lahvis, L.C. Rehmann
1999, Conference Paper, API - National Ground Water Association Petroleum Hydrocarbons and Organic Chemicals in Ground Water: Prevention, Detection and Remediation Joint Conference Proceedings
The mathematical model, R-UNSAT, developed to simulate the transport of benzene and MTBE in representative sand and clay hydrogeologic systems was evaluated. The effects on groundwater were simulated for small, chronic-, and single-volume releases of gasoline trapped in unsaturated soil. Hydrocarbon biodegradation was simulated by using a dual Monod-type kinetics...
Mortality of riparian box elder from sediment mobilization and extended inundation
Jonathan M. Friedman, Gregor T. Auble
1999, Regulated Rivers: Research & Management (15) 463-476
To explore how high flows limit the streamward extent of riparian vegetation we quantified the effects of sediment mobilization and extended inundation on box elder (Acer negundo) saplings along the cobble-bed Gunnison River in Black Canyon of the Gunnison National Monument, Colorado, USA. We counted and aged box elders in...
Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA
C. A. Crandall, B. G. Katz, J.J. Hirten
1999, Hydrogeology Journal (7) 454-467
Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88 m above mean sea level in...
Chronologic model and transgressive-regressive signatures in the late neocene siliciclastic foundation (long key formation) of the Florida keys
L.A. Guertin, D.F. McNeill
1999, Journal of Sedimentary Research (69) 653-666
Recent drilling of continuous cores in southernmost Florida has documented a thick unit of upper Neogene siliciclastics subjacent to surficial shallow-water Quaternary carbonates exposed on islands of the Florida Keys. The siliciclastics comprise the Long Key Formation and were identified in two cores...
Integration of high-resolution seismic and aeromagnetic data for earthquake hazards evaluations: An example from the Willamette Valley, Oregon
L.M. Liberty, A.M. Trehu, R.J. Blakely, M.E. Dougherty
1999, Bulletin of the Seismological Society of America (89) 1473-1483
Aeromagnetic and high-resolution seismic reflection data were integrated to place constraints on the history of seismic activity and to determine the continuity of the possibly active, yet largely concealed Mount Angel fault in the Willamette Valley, Oregon. Recent seismic activity possibly related to...
Volatile organic compounds in untreated ambient groundwater of the United States, 1985-1995
P. J. Squillace, M.J. Moran, W.W. Lapham, C. V. Price, R.M. Clawges, J.S. Zogorski
1999, Environmental Science & Technology (33) 4176-4187
As part of the National Water-Quality Assessment Program of the U.S. Geological Survey, an assessment of 60 volatile organic compounds (VOCs) in untreated, ambient groundwater of the conterminous United States was conducted based on samples collected from 2948 wells between 1985 and 1995. The samples represent urban and rural areas...
Deformation across the Alaska-Aleutian Subduction Zone near Kodiak
J.C. Savage, J. L. Svarc, W.H. Prescott
1999, Geophysical Research Letters (26) 2117-2120
The Kodiak-Katmai geodetic array, nine monuments distributed along a profile trending north-northwestward across Kodiak Island and the Alaska Peninsula, was surveyed in 1993, 1995 and 1997 to determine the deformation at the Alaska-Aleutian subduction zone. Velocities on Kodiak island measured relative to the stable North American...
Calculation of broadband time histories of ground motion: Comparison of methods and validation using strong-ground motion from the 1994 Northridge earthquake
S. Hartzell, S. Harmsen, A. Frankel, S. Larsen
1999, Bulletin of the Seismological Society of America (89) 1484-1504
This article compares techniques for calculating broadband time histories of ground motion in the near field of a finite fault by comparing synthetics with the strong-motion data set for the 1994 Northridge earthquake. Based on this comparison, a preferred methodology is presented. Ground-motion-simulation...
Kinematic analysis of melange fabrics: Examples and applications from the McHugh Complex, Kenai Peninsula, Alaska
T.M. Kusky, D. C. Bradley
1999, Journal of Structural Geology (21) 1773-1796
Permian to Cretaceous melange of the McHugh Complex on the Kenai Peninsula, south-central Alaska includes blocks and belts of graywacke, argillite, limestone, chert, basalt, gabbro, and ultramafic rocks, intruded by a variety of igneous rocks. An oceanic plate stratigraphy is repeated hundreds of times across the map area, but most...
Use of generalized linear models and digital data in a forest inventory of northern Utah
Gretchen G. Moisen, Thomas C. Edwards Jr.
1999, Journal of Agricultural, Biological, and Environmental Statistics (4) 372-390
Forest inventories, like those conducted by the Forest Service's Forest Inventory and Analysis Program (FIA) in the Rocky Mountain Region, are under increased pressure to produce better information at reduced costs. Here we describe our efforts in Utah to merge satellite-based information with forest inventory data for the purposes of...
Protocol and practice in the adaptive management of waterfowl harvests
F. Johnson, K. Williams
1999, Conservation Ecology (3)
Waterfowl harvest management in North America, for all its success, historically has had several shortcomings, including a lack of well-defined objectives, a failure to account for uncertain management outcomes, and inefficient use of harvest regulations to understand the effects of management. To address these and other concerns, the U.S. Fish...
Aeromagnetic legacy of early Paleozoic subduction along the Pacific margin of Gondwana
Carol A. Finn, D. Moore, D. Damaske, T. Mackey
1999, Geology (27) 1087-1090
Comparison of the aeromagnetic signatures and geology of southeastern Australia and northern Victoria Land, Antarctica, with similar data from ancient subduction zones in California and Japan, provides a framework for reinterpretation of the plate tectonic setting of the Pacific margin of early Paleozoic Gondwana. In our model, the plutons in...
Estimates of runoff using water-balance and atmospheric general circulation models
D.M. Wolock, G.J. McCabe
1999, Conference Paper, Journal of the American Water Resources Association
The effects of potential climate change on mean annual runoff in the conterminous United States (U.S.) are examined using a simple water-balance model and output from two atmospheric general circulation models (GCMs). The two GCMs are from the Canadian Centre for Climate Prediction and Analysis (CCC) and the Hadley Centre...
Fluid inclusion and vitrinite-reflectance geothermometry compared to heat-flow models of maximum paleotemperature next to dikes, western onshore Gippsland Basin, Australia
C.E. Barker, Y. Bone, M. D. Lewan
1999, International Journal of Coal Geology (37) 73-111
Nine basalt dikes, ranging from 6 cm to 40 m thick, intruding the Upper Jurassic–Lower Cretaceous Strzelecki Group, western onshore Gippsland Basin, were used to study maximum temperatures (Tmax) reached next...
Management of groundwater supply and water quality in the Los Angeles Basin, California
E.G. Reichard, S.M. Crawford, M.T. Land, K.S. Paybins
1999, Conference Paper, IAHS-AISH Publication
Water use and water needs in the coastal Los Angeles Basin in California have been very closely tied to the development of the region during the last 150 years. The first water wells were drilled in the mid-1800s. Currently about 40% of the water supply (9.4 m3 s-1) in the...
General-circulation-model simulations of future snowpack in the western United States
G.J. McCabe, D.M. Wolock
1999, Conference Paper, Journal of the American Water Resources Association
April 1 snowpack accumulations measured at 311 snow courses in the western United States (U.S.) are grouped using a correlation-based cluster analysis. A conceptual snow accumulation and melt model and monthly temperature and precipitation for each cluster are used to estimate cluster-average April 1 snowpack. The conceptual snow model is...
Slip-rate increase at Parkfield in 1993 detected by high-precision EDM and borehole tensor strainmeters
J. Langbein, R. L. Gwyther, R.H.G. Hart, M. T. Gladwin
1999, Geophysical Research Letters (26) 2529-2532
On two of the instrument networks at Parkfield, California, the two-color Electronic Distance Meter (EDM) network and Borehole Tensor Strainmeter (BTSM) network, we have detected a rate change starting in 1993 that has persisted at least 5 years. These and other instruments capable of measuring crustal deformation were installed at...
Climate and lake-level history of the northern altiplano, Bolivia, as recorded in holocene sediments of the Rio Desaguadero
P.C. Baucom, C.A. Rigsby
1999, Journal of Sedimentary Research (69) 597-611
Strata exposed in terraces and modern cutbanks along the Rio Desaguadero contain a variety of lithofacies that were deposited in four distinct facies associations. These facies associations document a history of aggradation and downcutting that is linked to Holocene climate change on the...
Petrology and geochemistry of late-stage intrusions of the A-type, mid-Proterozoic Pikes Peak batholith (Central Colorado, USA): Implications for petrogenetic models
D. R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J. Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
1999, Precambrian Research (98) 271-305
The ~1.08 Ga anorogenic, A-type Pikes Peak batholith (Front Range, central Colorado) is dominated by coarse-grained, biotite ?? amphibole syenogranites and minor monzogranites, collectively referred to as Pikes Peak granite (PPG). The batholith is also host to numerous small, late-stage plutons that have been subdivided into two groups (e.g. Wobus,...
The strain in the array is mainly in the plane (waves below ~1 Hz)
J. Gomberg, G. Pavlis, P. Bodin
1999, Bulletin of the Seismological Society of America (89) 1428-1438
We compare geodetic and single-station methods of measuring dynamic deformations and characterize their causes in the frequency bands 0.5-1.0 Hz and 4.0-8.0 Hz. The geodetic approach utilizes data from small-aperture seismic arrays, applying techniques from geodesy. It requires relatively few assumptions and a priori information....
Immunostimulants in fish diets
A.L. Gannam, R. M. Schrock
1999, Journal of Applied Aquaculture (9) 53-89
Various immunostimulants and their methods of application in fish culture are examined in this review. Important variables such as life stage and innate disease resistance of the fish; immunostimulant used, its structure and mode of action; and the fish's environment are discussed. Conflicting results have been published about the efficacy...
