Fatal toxoplasmosis in free-ranging endangered 'Alala from Hawaii
Thierry M. Work, J. Gregory Massey, Bruce A. Rideout, Chris H. Gardiner, David B. Ledig, O. C. H. Kwok, J. P. Dubey
2000, Journal of Wildlife Diseases (36) 205-212
The ‘Alala (Corvus hawaiiensis) is the most endangered corvid in the world, and intensive efforts are being made to reintroduce it to its former native range in Hawaii. We diagnosed Toxoplasma gondii infection in five free-ranging ‘Alala. One ‘Alala, recaptured from the wild because it was underweight and depressed, was...
Historical forest patterns of Oregon's central Coast Range
W. J. Ripple, K.T. Hershey, R.G. Anthony
2000, Biological Conservation (93) 127-133
To describe the composition and pattern of unmanaged forestland in Oregon's central Coast Range, we analyzed forest conditions from a random sample of 18 prelogging (1949 and earlier) landscapes. We also compared the amount and variability of old forest (conifer-dominated stands > 53 cm dbh) in the prelogging landscapes with...
Fumaroles in ice caves on the summit of Mount Rainier: preliminary stable isotope, gas, and geochemical studies
D. R. Zimbelman, R. O. Rye, G. P. Landis
2000, Book, Journal of Volcanology and Geothermal Research
The edifice of Mount Rainier, an active stratovolcano, has episodically collapsed leading to major debris flows. The largest debris flows are related to argillically altered rock which leave areas of the edifice prone to failure. The argillic alteration results from the neutralization of acidic magmatic gases that condense in a...
Palaeohydrology, vegetation, and climate since the late Illinois Episode (~130 ka) in south-central Illinois
B. Brandon Curry, R. G. Baker
2000, Conference Paper, Palaeogeography, Palaeoclimatology, Palaeoecology
Our interpretation of pollen and ostracode successions from four basins in south-central Illinois provides a new synthesis of palaeovegetation, palaeohydrology, and palaeoclimate for the period from the late Illinois Episode (about 130,000 years ago) to near the end of the Wisconsin Episode (about 25,000 years ago). Correlations of pollen biozones...
Guidelines for model calibration and application to flow simulation in the Death Valley regional groundwater system
M. C. Hill, F. A. D’Agnese, C.C. Faunt
2000, Conference Paper, IAHS-AISH Publication
Fourteen guidelines are described which are intended to produce calibrated groundwater models likely to represent the associated real systems more accurately than typically used methods. The 14 guidelines are discussed in the context of the calibration of a regional groundwater flow model of the Death Valley region in the southwestern...
Colorado River sediment transport: 2. Systematic bed‐elevation and grain‐size effects of sand supply limitation
David J. Topping, David M. Rubin, Jonathan M. Nelson, Paul J. Kinzel III, Ingrid C. Corson
2000, Water Resources Research (36) 543-570
The Colorado River in Marble and Grand Canyons displays evidence of annual supply limitation with respect to sand both prior to [Topping et al, this issue] and after the closure of Glen Canyon Dam in 1963. Systematic changes in bed elevation and systematic coupled changes in suspended‐sand concentration and grain...
Effects of neck bands on survival of greater snow geese
S. Menu, J.B. Hestbeck, G. Gauthier, A. Reed
2000, Journal of Wildlife Management (64) 544-552
Neck bands are a widely used marker in goose research. However, few studies have investigated a possible negative effect of this marker on survival. We tested the effect of neck bands on the survival of adult female greater snow geese (Chen caerulescens atlantica) by marking birds with either a neck...
Parent brine of the castile evaporites (Upper Permian), Texas and New Mexico
Douglas W. Kirkland, Rodger E. Denison, Walter E. Dean
2000, Journal of Sedimentary Research (70) 749-761
The Upper Permian (lower Ochoan) Castile Formation is a major evaporite sequence (∼10,000 km3) of calcite, anhydrite, and halite in west Texas and southeastern New Mexico. Traditionally the Castile brine has been considered to have been derived from seawater. This tradition has recently been challenged by two versions of the...
Spatial modeling of the geographic distribution of wildlife populations: A case study in the lower Mississippi River region
W. Ji, C. Jeske
2000, Ecological Modelling (132) 95-104
A geographic information system (GIS)-based spatial modeling approach was developed to study environmental and land use impacts on the geographic distribution of wintering northern pintails (Arias acuta) in the Lower Mississippi River region. Pintails were fitted with backpack radio transmitter packages at Catahoula Lake, LA, in October 1992-1994 and located...
Reservoir characterization of marine and permafrost associated gas hydrate accumulations with downhole well logs
T. S. Collett, Myung W. Lee
2000, Conference Paper, Annals of the New York Academy of Sciences
Gas volumes that may be attributed to a gas hydrate accumulation depend on a number of reservoir parameters, one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well-logging devices. This study demonstrates that electrical resistivity and acoustic transit-time downhole log data can be used to quantify...
Formation of natural gas hydrates in marine sediments. Gas hydrate growth and stability conditioned by host sediment properties
M. B. Clennell, P. Henry, M. Hovland, J.S. Booth, W.J. Winters, M. Thomas
2000, Conference Paper, Annals of the New York Academy of Sciences
The stability conditions of submarine gas hydrates (methane clathrates) are largely dictated by pressure, temperature, gas composition, and pore water salinity. However, the physical properties and surface chemistry of the host sediments also affect the thermodynamic state, growth kinetics, spatial distributions, and growth forms of clathrates. Our model presumes that...
Identification of a basaltic component on the Martian surface from Thermal Emission Spectrometer data
P. R. Christensen, J. L. Bandfield, M. D. Smith, V.E. Hamilton, Roger N. Clark
2000, Journal of Geophysical Research: Planets (105) 9609-9621
The Mars Global Surveyor Thermal Emission Spectrometer (TES) instrument collected 4.8×106 spectra of Mars during the initial aerobraking and science‐phasing periods of the mission (September 14, 1997, through April 29, 1998). Two previously developed atmosphere‐removal models were applied to data from Cimmeria Terra (25°S, 213°W). The surface spectra derived for these...
Pyroclast/snow interactions and thermally driven slurry formation. Part 1: Theory for monodisperse grain beds
J. S. Walder
2000, Bulletin of Volcanology (62) 105-118
Lahars are often produced as pyroclastic flows move over snow. This phenomenon involves a complicated interplay of mechanical and thermal processes that need to be separated to get at the fundamental physics. The thermal physics of pyroclast/snow interactions form the focus of this paper. A theoretical model is developed of...
Geochemical and mineralogical evidence from eolian sediments for northwesterly mid-Holocene paleowinds, central Kansas, USA
A.F. Arbogast, D.R. Muhs
2000, Quaternary International (67) 107-118
A prominent (4500 km2) dune field in the Great Plains is the Great Bend Sand Prairie of south-central Kansas. Dunes here overlie late Quaternary alluvium and were reactivated extensively in the late Holocene. Geomorphic and soil evidence suggests that the most likely eolian sand source is the Arkansas River valley...
Responses of stable bay-margin and barrier-island systems to Holocene sea-level highstands, western Gulf of Mexico
Robert A. Morton, Jeffrey G. Paine, Michael D. Blum
2000, Journal of Sedimentary Research (70) 478-490
The microtidal, wave-dominated coast of the western Gulf of Mexico displays a variety of Holocene geomorphic features indicating higher-than-present water levels that were previously attributed to storm processes while geoidal sea level was at its present position. Field and aerial-photograph examinations of bay margins, barrier islands, and beach-ridge plains following...
Dynamics of prey moving through a predator field: a model of migrating juvenile salmon
J.H. Petersen, D.L. DeAngelis
2000, Mathematical Biosciences (165) 97-114
The migration of a patch of prey through a field of relatively stationary predators is a situation that occurs frequently in nature. Making quantitative predictions concerning such phenomena may be difficult, however, because factors such as the number of the prey in the patch, the spatial length and velocity of...
Historical eruptions of Merapi Volcano, Central Java, Indonesia, 1768-1998
B. Voight, E.K. Constantine, S. Siswowidjoyo, R. Torley
2000, Journal of Volcanology and Geothermal Research (100) 69-138
Information on Merapi eruptive activity is scattered and much is remotely located. A concise and well-documented summary of this activity has been long needed to assist researchers and hazard-mitigation efforts, and the aim of this paper is to synthesize information from the mid-1700s to the present. A descriptive chronology is...
Detection of crystalline hematite mineralization on Mars by the Thermal Emission Spectrometer: evidence for near-surface water
P. R. Christensen, J. L. Bandfield, R. N. Clark, K.S. Edgett, V.E. Hamilton, T. Hoefen, H. H. Kieffer, R.O. Kuzmin, M. D. Lane, M. C. Malin, R.V. Morris, J.C. Pearl, R. Pearson, T. L. Roush, S. W. Ruff, M. D. Smith
2000, Journal of Geophysical Research E: Planets (105) 9623-9642
The Thermal Emission Spectrometer (TES) instrument on the Mars Global Surveyor (MGS) mission has discovered a remarkable accumulation of crystalline hematite (α-Fe2O3) that covers an area with very sharp boundaries approximately 350 by 350–750 km in size centered near 2°S latitude between 0° and 5°W longitude (Sinus Meridiani). Crystalline hematite...
Quantifying precambrian crustal extraction: The root is the answer
D. Abbott, D. Sparks, C. Herzberg, Walter D. Mooney, A. Nikishin, Y.-S. Zhang
2000, Tectonophysics (322) 163-190
We use two different methods to estimate the total amount of continental crust that was extracted by the end of the Archean and the Proterozoic. The first method uses the sum of the seismic thickness of the crust, the eroded thickness of the...
Late-kinematic timing of orogenic gold deposits and significance for computer-based exploration techniques with emphasis on the Yilgarn Block, Western Australia
D.I. Groves, R.J. Goldfarb, C. M. Knox-Robinson, J. Ojala, S. Gardoll, G.Y. Yun, P. Holyland
2000, Ore Geology Reviews (17) 1-38
Orogenic gold deposits are a widespread coherent group of epigenetic ore deposits that are sited in accretionary or collisional orogens. They formed over a large crustal-depth range from deep-seated low-salinity H2O–CO2±CH4±N2 ore fluids and with Au transported as thio-complexes. Regional structures provide the main control on deposit distribution. In many terranes,...
Sediment loads and accumulation in a small riparian wetland system in northern Missouri
David C. Heimann, Michael J. Roell
2000, Wetlands (20) 219-231
Sediment transport and deposition along a stream in an agricultural basin (65 km2) in northern Missouri, USA were quantified as part of a long-term study to evaluate effects of silvicultural practices on the hydrology, sediment, vegetation, and wildlife characteristics of remaining forested riparian systems. Median cumulative sediment deposition, measured using...
Relation of pathways and transit times of recharge water to nitrate concentrations using stable isotopes
M.K. Landon, G. N. Delin, S.C. Komor, C.P. Regan
2000, Ground Water (38) 381-395
Oxygen and hydrogen stable isotope values of precipitation, irrigation water, soil water, and ground water were used with soil-moisture contents and water levels to estimate transit times and pathways of recharge water in the unsaturated zone of a sand and gravel aquifer. Nitrate-nitrogen (nitrate) concentrations in ground water were also...
Winter survival of adult female harlequin ducks in relation to history of contamination by the Exxon Valdez oil spill
Daniel Esler, Joel A. Schmutz, R. L. Jarvis, D.M. Mulcahy
2000, Journal of Wildlife Management (64) 839-847
Harlequin duck (Histrionicus histrionicus) life-history characteristics make their populations particularly vulnerable to perturbations during nonbreeding periods. The 1989 Exxon Valdez oil spill was a major perturbation to nonbreeding habitats of harlequin ducks in Prince William Sound, Alaska, which resulted in population injury. To assess the status of population recovery from...
Hydrothermal diamond anvil cell for XAFS studies of first-row transition elements in aqueous solutions up to supercritical conditions
William A. Bassett, Alan J. Anderson, Robert A. Mayanovic, I.-M. Chou
2000, Conference Paper, Chemical Geology
A hydrothermal diamond anvil cell (HDAC) has been modified by drilling holes with a laser to within 150 ??m of the anvil face to minimize the loss of X-rays due to absorption and scatter by diamond. This modification enables acquisition of K-edge X-ray absorption fine structure (XAFS) spectra from first-row...
Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns
Daniel H. Monson, Daniel F. Doak, Brenda E. Ballachey, Aaron H. Johnson, James L. Bodkin
2000, Proceedings of the National Academy of Sciences of the United States of America (97) 6562-6567
We use age distributions of sea otters (Enhydra lutris) found dead on beaches of western Prince William Sound, Alaska, between 1976 and 1998 in conjunction with time-varying demographic models to test for lingering effects from the 1989 Exxon Valdez oil spill. Our results show that sea otters in this area had decreased...
