Myrmecophagy by Yellowstone grizzly bears
David J. Mattson
2001, Canadian Journal of Zoology (79) 779-793
I used data collected during a study of radio-marked grizzly bears (Ursus arctos horribilis) in the Yellowstone region from 1977 to 1992 to investigate myrmecophagy by this population. Although generally not an important source of energy for the bears (averaging <5% of fecal volume at peak consumption), ants may have...
Survey of fishes and environmental conditions in Abbotts Lagoon, Point Reyes National Seashore, California
M. K. Saiki, B.A. Martin
2001, California Fish and Game (87) 123-138
This study was conducted to gain a better understanding of fishery resources in Abbotts Lagoon, Point Reyes National Seashore. During February/March, May, August, and November 1999, fish were sampled with floating variable-mesh gill nets and small minnow traps from as many as 14 sites in the lagoon. Water temperature, dissolved...
Resolution analysis of finite fault source inversion using one- and three-dimensional Green's functions 2. Combining seismic and geodetic data
D.J. Wald, R.W. Graves
2001, Journal of Geophysical Research B: Solid Earth (106) 8767-8788
Using numerical tests for a prescribed heterogeneous earthquake slip distribution, we examine the importance of accurate Green's functions (GF) for finite fault source inversions which rely on coseismic GPS displacements and leveling line uplift alone and in combination with near-source strong ground motions. The static displacements, while sensitive to the...
The Precambrian terranes of Yemen and their correlation with those of Saudi Arabia and Somalia: Implications for the accretion of Gondwana
B.F. Windley, M.J. Whitehouse, D. B. Stoeser, S. Al-Khirbash, M. A. O. Ba-Bttat, A. Al-Ghotbah
2001, Gondwana Research (4) 206-207
Most of the basement of Yemen consists of early Precambrian continental high-grade terranes and Neoproterozoic low-grade island arcs that were accreted together to form an arc-continent collage during the Pan-African orogeny (Windley et al., 1996; Whitehouse et al., 1998; Whitehouse et al., in press)....
A rule-based model for mapping potential exotic plant distribution
Don G. Despain, T. Weaver, R.J. Aspinall
2001, Western North American Naturalist (61) 428-433
Wildland managers need a method to predict which portions of the lands under their stewardship are susceptible to invasion by exotic plants. We combined a database listing exotic plant species known to occur in major environmental types (habitat types) throughout the northern Rocky Mountains with a digital vegetation map of...
Trace metal suites in Antarctic pre-industrial ice are consistent with emissions from quiescent degassing of volcanoes worldwide
A. Matsumoto, T. K. Hinkley
2001, Earth and Planetary Science Letters (186) 33-43
Trace metals are more abundant in atmospheric load and deposition material than can be due to rock and soil dusts and ocean salt. In pre-industrial ice from coastal west Antarctica, dust and salt account for only a few percent of the lead, cadmium, and indium that is present in most...
Separating the effects of intra- and interspecific age-structured interactions in an experimental fish assemblage
R.C. Taylor, J.C. Trexler, W.F. Loftus
2001, Oecologia (127) 143-152
We documented patterns of age-structured biotic interactions in four mesocosm experiments with an assemblage of three species of co-occurring fishes from the Florida Everglades, the eastern mosquitofish (Gambusia holbrooki), sailfin molly (Poecilia latipinna), and bluefin killifish (Lucania goodei). These species were chosen based on their high abundance and overlapping diets....
Melt-inclusion-hosted excess 40Ar in quartz crystals of the Bishop and Bandelier magma systems
J. A. Winick, W. C. McIntosh, N. W. Dunbar
2001, Geology (29) 275-278
40Ar/39Ar experiments on melt-inclusion–bearing quartz (MIBQ) from the Bishop and Bandelier Tuff Plinian deposits indicate high concentrations of excess 40Ar in melt inclusions. Two rhyolite glass melt inclusion populations are present in quartz; exposed melt inclusions and trapped melt inclusions. Air-abrasion mill grinding and hydrofluoric acid treatments progressively remove exposed melt...
Identifying unprotected and potentially at risk plant communities in the western USA
R.G. Wright, J. M. Scott, S. Mann, M. Murray
2001, Biological Conservation (98) 97-106
We analyzed the conservation status of 73 vegetation cover types distributed across a 1.76 million km2 region in 10 states of the western USA. We found that 25 vegetation cover types had at least 10% of their area in nature reserves. These were generally plant communities located at higher elevations...
Flow of variably fluidized granular masses across three-dimensional terrain 2. Numerical predictions and experimental tests
R.P. Denlinger, R.M. Iverson
2001, Journal of Geophysical Research B: Solid Earth (106) 553-566
Numerical solutions of the equations describing flow of variably fluidized Coulomb mixtures predict key features of dry granular avalanches and water-saturated debris flows measured in physical experiments. These features include time-dependent speeds, depths, and widths of flows as well as the geometry of resulting deposits. Threedimensional (3-D) boundary surfaces strongly...
Acidic deposition in the northeastern United States: Sources and inputs, ecosystem effects, and management strategies: The effects of acidic deposition in the northeastern United States include the acidification of soil and water, which stresses terrestrial and aquatic biota
C. T. Driscoll, Gregory B. Lawrence, Arthur J. Bulger, Thomas Butler, C. S. Cronan, C. Eagar, Kathleen Fallon Lambert, Gene E Likens, John L Stoddard, Kathleen C. Weathers
2001, BioScience (51) 180-198
Acidic deposition is the transfer of strong acids and acid-forming substances from the atmosphere to the surface of the Earth. The composition of acidic deposition includes ions, gases, and particles derived from the following: gaseous emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), ammonia (NH3), and particulate emissions of acidifying and...
Improving the quality of mass produced maps
Jeffrey D. Simley
2001, Cartography and Geographic Information Science (28) 97-110
Quality is critical in cartography because key decisions are often made based on the information the map communicates. The mass production of digital cartographic information to support geographic information science has now added a new dimension to the problem of cartographic quality, as problems once limited to small volumes can...
Timescales for nitrate contamination of spring waters, northern Florida, USA
B. G. Katz, J.K. Böhlke, H.D. Hornsby
2001, Chemical Geology (179) 167-186
Residence times of groundwater, discharging from springs in the middle Suwannee River Basin, were estimated using chlorofluorocarbons (CFCs), tritium (3H), and tritium/helium-3 (3H/3He) age-dating methods to assess the chronology of nitrate contamination of spring waters in northern Florida. During base-flow conditions for the Suwannee River in 1997–1999, 17 water samples...
Fault zone amplified waves as a possible seismic hazard along the Calaveras fault in central California
P. Spudich, K.B. Olsen
2001, Geophysical Research Letters (28) 2533-2536
The Calaveras fault lies within a low velocity zone (LVZ) 1-2 km wide near Gilroy, California. Accelerographs G06, located in the LVZ 1.2 km from the Calaveras fault, and G07, 4 km from G06, recorded both the M 6.2 1984 Morgan Hill and the M 6.9 1989 Loma Prieta earthquakes....
Experimental controls on D/H and 13C/12C ratios of kerogen, bitumen and oil during hydrous pyrolysis
A. Schimmelmann, J.-P. Boudou, M. D. Lewan, R. P. Wintsch
2001, Organic Geochemistry (32) 1009-1018
Large isotopic transfers between water-derived hydrogen and organic hydrogen occurred during hydrous pyrolysis experiments of immature source rocks, in spite of only small changes in organic 13C/12C. Experiments at 330 ??C over 72 h using chips or powder containing kerogen types I and III identify the rock/water ratio as a...
Foraging time and dietary intake by breeding ross's and lesser snow geese
M.L. Gloutney, R.T. Alisauskas, A. D. Afton, S. M. Slattery
2001, Oecologia (127) 78-86
We compared foraging times of female Ross's (Chen rossii) and Lesser Snow Geese (Chen caerulescens caerulescens) breeding at Karrak Lake, NT, Canada and examined variation due to time of day and reproductive stage. We subsequently collected female geese that had foraged for known duration and we estimated mass of foods...
Oblique sinistral transpression in the Arabian shield: The timing and kinematics of a Neoproterozoic suture zone
P.R. Johnson, F. Kattan
2001, Precambrian Research (107) 117-138
The Hulayfah-Ad Dafinah-Ruwah fault zone is a belt of highly strained rocks that extends in a broad curve across the northeastern Arabian shield. It is a subvertical shear zone, 5-30 km wide and over 600 km long, and is interpreted as a zone of oblique sinistral transpression that forms the...
Spatial extent of a hydrothermal system at Kilauea Volcano, Hawaii, determined from array analyses of shallow long-period seismicity 2. Results
J. Almendros, B. Chouet, P. Dawson
2001, Journal of Geophysical Research B: Solid Earth (106) 13581-13597
Array data from a seismic experiment carried out at Kilauea Volcano, Hawaii, in February 1997, are analyzed by the frequency-slowness method. The slowness vectors are determined at each of three small-aperture seismic antennas for the first arrivals of 1129 long-period (LP) events and 147 samples of volcanic tremor. The source...
Occurrence and Diversity of Tetracycline Resistance Genes in Lagoons and Groundwater Underlying Two Swine Production Facilities
J. C. Chee-Sanford, R.I. Aminov, I.J. Krapac, N. Garrigues-Jeanjean, R.I. Mackie
2001, Applied and Environmental Microbiology (67) 1494-1502
In this study, we used PCR typing methods to assess the presence of tetracycline resistance determinants conferring ribosomal protection in waste lagoons and in groundwater underlying two swine farms. All eight classes of genes encoding this mechanism of resistance [tet(O), tet(Q), tet(W), tet(M), tetB(P), tet(S), tet(T), and otrA] were found...
Sediment quality in Burlington Harbor, Lake Champlain, U.S.A.
E.M. Lacey, J.W. King, J.G. Quinn, E.L. Mecray, P.G. Appleby, A.S. Hunt
2001, Water, Air, & Soil Pollution (126) 97-120
Surface samples and cores were collected in 1993 from the Burlington Harbor region of Lake Champlain. Sediment samples were analyzed for trace metals (cadmium, copper, lead, nickel, silver and zinc), simultaneously extracted metal/acid volatile sulfide (SEM-AVS), grain size, nutrients (carbon and nitrogen) and organic contaminants (polycyclic aromatic hydrocarbons (PAHs) and...
New views of granular mass flows
R.M. Iverson, J.W. Vallance
2001, Geology (29) 115-118
Concentrated grain-fluid mixtures in rock avalanches, debris flows, and pyroclastic flows do not behave as simple materials with fixed rheologies. Instead, rheology evolves as mixture agitation, grain concentration, and fluid-pressure change during flow initiation, transit, and deposition. Throughout a flow, however, normal forces on planes parallel to the free upper...
A minimalist probabilistic description of root zone soil water
P. C. D. Milly
2001, Water Resources Research (37) 457-463
The probabilistic response of depth‐integrated soil water to given climatic forcing can be described readily using an existing supply‐demand‐storage model. An apparently complex interaction of numerous soil, climate, and plant controls can be reduced to a relatively simple expression for the equilibrium probability density function of soil water as a...
Effects of acidic recharge on groundwater at the St. Kevin Gulch site, Leadville, Colorado
S.S. Paschke, W.J. Harrison, K. Walton-Day
2001, Geochemistry: Exploration, Environment, Analysis (1) 3-14
The acid rock drainage-affected stream of St. Kevin Gulch recharges the Quaternary sand and gravel aquifer of Tennessee Park, near Leadville, Colorado, lowering pH and contributing iron, cadmium, copper, zinc and sulphate to the ground-water system. Dissolved metal mobility is controlled by the seasonal spring runoff as well as oxidation/reduction...
Selection of habitats by Emperor Geese during brood rearing
Joel A. Schmutz
2001, Waterbirds (24) 394-401
Although forage quality strongly affects gosling growth and consequently juvenile survival, the relative use of different plant communities by brood rearing geese has been poorly studied. On the Yukon-Kuskokwim Delta, Alaska, population growth and juvenile recruitment of Emperor Geese (Chen canagica) are comparatively low, and it is unknown whether their...
Aerogeophysical measurements of collapse-prone hydrothermally altered zones at Mount Rainier volcano
C. A. Finn, T. W. Sisson, M. Deszcz-Pan
2001, Nature (409) 600-603
Hydrothermally altered rocks can weaken volcanoes, increasing the potential for catastrophic sector collapses that can lead to destructive debris flows1. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes1-4 and the distribution and severity of subsurface alteration is largely unknown on...
