Field and laboratory arsenic speciation methods and their application to natural-water analysis
A.J. Bednar, J.R. Garbarino, M.R. Burkhardt, J. F. Ranville, T.R. Wildeman
2004, Water Research (38) 355-364
The toxic and carcinogenic properties of inorganic and organic arsenic species make their determination in natural water vitally important. Determination of individual inorganic and organic arsenic species is critical because the toxicology, mobility, and adsorptivity vary substantially. Several methods for the speciation of arsenic in groundwater, surface-water, and acid mine...
Foraging distance and home range of Cassin's Auklets nesting at two colonies in the California Channel Islands
Josh Adams, John Y. Takekawa, Harry R. Carter
2004, Condor (106) 618-637
We radio-marked 99 Cassin's Auklets (Ptychoramphus aleuticus) nesting at two colonies, Prince Island and Scorpion Rock, separated by 90 km in the California Channel Islands to quantify foraging distance, individual home-range area, and colony-based foraging areas during three consecutive breeding seasons. Auklets generally foraged < 30 km from each colony...
Lack of spatial genetic structure among nesting and wintering King Eiders
John M. Pearce, Sandra L. Talbot, Barbara J. Pierson, Margaret R. Petersen, Kim T. Scribner, D. Lynne. Dickson, Anders Mosbech
2004, Condor (106) 229-240
The King Eider (Somateria spectabilis) has been delineated into two broadly distributed breeding populations in North America (the western and eastern Arctic) on the basis of banding data and their use of widely separated Pacific and Atlantic wintering areas. Little is known about the level of gene flow between these...
The influence of diet, consumption and lipid use on recruitment of white bass
W.J. Eckmayer, F.J. Margraf
2004, Lakes and Reservoirs: Research and Management (9) 133-141
The abundance of white bass (Morone chrysops) in Lake Erie has declined in recent years, sparking interest in mechanisms influencing its recruitment. We evaluate two mechanisms affecting recruitment: diet and the potential for competition, and storage of lipid energy reserves and the relationship to overwinter survival. The fish in our...
Spawning ecology of finespotted Snake River cutthroat trout in spring streams of the Salt River valley, Wyoming
M. P. Joyce, W.A. Hubert
2004, Western North American Naturalist (64) 78-85
We studied spawning ecology of cutthroat trout (Oncorhynchus clarki) in streams that originate as springs along the Salt River, a Snake River tributary in western Wyoming. We assessed (1) relative numbers of upstream-migrant and resident adults present during the spawning period in spring streams, (2) influence of habitat modification on...
Emissions pathways, climate change, and impacts on California
K. Hayhoe, D. Cayan, C.B. Field, P.C. Frumhoff, E.P. Maurer, N.L. Miller, S.C. Moser, S.H. Schneider, K.N. Cahill, E.E. Cleland, L. Dale, R. Drapek, R.M. Hanemann, L.S. Kalkstein, J. Lenihan, C.K. Lunch, R.P. Neilson, S.C. Sheridan, J.H. Verville
2004, Proceedings of the National Academy of Sciences of the United States of America (101) 12422-12427
The magnitude of future climate change depends substantially on the greenhouse gas emission pathways we choose. Here we explore the implications of the highest and lowest Intergovernmental Panel on Climate Change emissions pathways for climate change and associated impacts in California. Based on climate projections from two state-of-the-art climate models...
Fast ground-water mixing and basal recharge in an unconfined, alluvial aquifer, Konza LTER Site, Northeastern Kansas
G.L. Macpherson, M. Sophocleous
2004, Journal of Hydrology (286) 271-299
Ground-water chemistry and water levels at three levels in a well nest were monitored biweekly for two and a half years in a shallow unconfined floodplain aquifer in order to study the dynamics of such shallow aquifers. The aquifer, in northeastern Kansas, consists of high porosity, low hydraulic conductivity fine-grained...
The Rock Elm meteorite impact structure, Wisconsin: Geology and shock-metamorphic effects in quartz
B.M. French, W.S. Cordua, J. B. Plescia
2004, Geological Society of America Bulletin (116) 200-218
The Rock Elm structure in southwest Wisconsin is an anomalous circular area of highly deformed rocks, ∼6.5 km in diameter, located in a region of virtually horizontal undeformed sedimentary rocks. Shock-produced planar microstructures (PMs) have been identified in quartz grains in several lithologies associated with the structure: sandstones, quartzite pebbles,...
Diets and foraging behavior of northern Spotted Owls in Oregon
E.D. Forsman, R.G. Anthony, E. Charles Meslow, C.J. Zabel
2004, Journal of Raptor Research (38) 214-230
We describe local, regional, and annual variation in diets of northern Spotted Owls (Strix occidentalis caurina) in Oregon based on 24 497 prey collected at 1118 owl territories in 1970-2003. The sample included 91.5% mammals, 4.3% birds, 4.1% insects, and 0.1% other prey. The diet included ???131 species, including 49...
Linear model describing three components of flow in karst aquifers using 18O data
Andrew J. Long, L.D. Putnam
2004, Journal of Hydrology (296) 254-270
The stable isotope of oxygen, 18O, is used as a naturally occurring ground-water tracer. Time-series data for ??18O are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid...
A definitive calibration record for the Landsat-5 thematic mapper anchored to the Landsat-7 radiometric scale
P.M. Teillet, D. L. Helder, T.A. Ruggles, R. Landry, F.J. Ahern, N.J. Higgs, J. Barsi, G. Chander, B. L. Markham, J. L. Barker, K. J. Thome, J. R. Schott, Frank Don Palluconi
2004, Canadian Journal of Remote Sensing (30) 631-643
A coordinated effort on the part of several agencies has led to the specification of a definitive radiometric calibration record for the Landsat-5 thematic mapper (TM) for its lifetime since launch in 1984. The time-dependent calibration record for Landsat-5 TM has been placed on the same radiometric scale as the...
Effects of predation risk on habitat selection by water column fish, benthic fish and crayfish in stream pools
D.D. Magoulick
2004, Hydrobiologia (527) 209-221
Predation risk can affect habitat selection by water column stream fish and crayfish, but little is known regarding effects of predation risk on habitat selection by benthic fish or assemblages of fish and crayfish. I used comparative studies and manipulative field experiments to determine whether, (1) habitat selection by stream...
Age and growth of flathead catfish, Pylodictus olivaris rafinesque, in the Altamaha River system, Georgia
T.B. Grabowski, J. Jeffery Isely, R.R. Weller
2004, Journal of Freshwater Ecology (19) 411-417
Flathead catfish were introduced to the Altamaha River system, Georgia in the 1970's. We determined the length-weight relationship, Von Bertalanffy growth parameters, and back calculated lengths by examining the sagittal otoliths of 331 individuals captured from this population. We found that there were no sex related differences in length weight...
Rabies in a captive colony of big brown bats (Eptesicus fuscus)
V. Shankar, R. A. Bowen, A. D. Davis, C. E. Rupprecht, T. J. O'Shea
2004, Journal of Wildlife Diseases (40) 403-413
Our research has focused on the ecology of commensal populations of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado (USA), in relation to rabies virus (RV) transmission. We captured 35 big brown bats (Eptesicus fuscus) in late summer 2001 and held them captive for 4.8 mo. The bats were...
Magnitudes and locations of the 1811-1812 New Madrid, Missouri, and the 1886 Charleston, South Carolina, earthquakes
W. H. Bakun, M. G. Hopper
2004, Bulletin of the Seismological Society of America (94) 64-75
We estimate locations and moment magnitudes M and their uncertainties for the three largest events in the 1811–1812 sequence near New Madrid, Missouri, and for the 1 September 1886 event near Charleston, South Carolina. The intensity magnitude MI, our preferred estimate of M, is 7.6 for the 16 December 1811 event that occurred in...
Geospatial data resampling and resolution effects on watershed modeling: A case study using the agricultural non-point source pollution model
E.L. Usery, M.P. Finn, Daniel J. Scheidt, S. Ruhl, T. Beard, M. Bearden
2004, Journal of Geographical Systems (6) 289-306
Researchers have been coupling geographic information systems (GIS) data handling and processing capability to watershed and waterquality models for many years. This capability is suited for the development of databases appropriate for water modeling. However, it is rare for GIS to provide direct inputs to the models. To demonstrate the...
Monitoring suspended sediment and associated trace element and nutrient fluxes in large river basins in the USA
A. J. Horowitz
2004, Conference Paper, IAHS-AISH Publication
In 1996, the US Geological Survey converted its occurrence and distribution-based National Stream Quality Accounting Network (NASQAN) to a national, flux-based water-quality monitoring programme. The main objective of the revised programme is to characterize large USA river basins by measuring the fluxes of selected constituents at critical nodes in various...
Methods for estimating adsorbed uranium(VI) and distribution coefficients of contaminated sediments
M. Kohler, G.P. Curtis, D.E. Meece, J.A. Davis
2004, Environmental Science & Technology (38) 240-247
Assessing the quantity of U(VI) that participates in sorption/desorption processes in a contaminated aquifer is an important task when investigating U migration behavior. U-contaminated aquifer sediments were obtained from 16 different locations at a former U mill tailings site at Naturita, CO (U.S.A.) and were extracted with an artificial groundwater,...
Geographic variation in patterns of nestedness among local stream fish assemblages in Virginia
R.R. Cook, P. L. Angermeier, D.S. Finn, N.L. Poff, K.L. Krueger
2004, Oecologia (140) 639-649
Nestedness of faunal assemblages is a multiscale phenomenon, potentially influenced by a variety of factors. Prior small-scale studies have found freshwater fish species assemblages to be nested along stream courses as a result of either selective colonization or extinction. However, within-stream gradients in temperature and other factors are correlated with...
Contrasting glacial/interglacial regimes in the western Arctic Ocean as exemplified by a sedimentary record from the Mendeleev Ridge
L. Polyak, W.B. Curry, D. A. Darby, J. Bischof, T. M. Cronin
2004, Palaeogeography, Palaeoclimatology, Palaeoecology (203) 73-93
Distinct cyclicity in lithology and microfaunal distribution in sediment cores from the Mendeleev Ridge in the western Arctic Ocean (water depths ca. 1. 5 km) reflects contrasting glacial/interglacial sedimentary patterns. We conclude that during major glaciations extremely thick pack ice or ice shelves covered the western Arctic Ocean and its...
Improved 206Pb/238U microprobe geochronology by the monitoring of a trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards
L.P. Black, S.L. Kamo, C. M. Allen, D.W. Davis, J. N. Aleinikoff, J.W. Valley, R. Mundil, I.H. Campbell, R.J. Korsch, I.S. Williams, C. Foudoulis
2004, Chemical Geology (205) 115-140
Precise isotope dilution-thermal ionisation mass spectrometry (ID-TIMS) documentation is given for two new Palaeozoic zircon standards (TEMORA 2 and R33). These data, in combination with results for previously documented standards (AS3, SL13, QGNG and TEMORA 1), provide the basis for a detailed investigation of inconsistencies in 206Pb/238U ages measured by...
Toward mapping surface deformation in three dimensions using InSAR
Tim J. Wright, Barry E. Parsons, Zhong Lu
2004, Geophysical Research Letters (31)
One of the limitations of deformation measurements made with interferometric synthetic aperture radar (InSAR) is that an interferogram only measures one component of the surface deformation — in the satellite's line of sight. We investigate strategies for mapping surface deformation in three dimensions by using multiple interferograms, with different imaging...
Structural complexity and land-surface energy exchange along a gradient from arctic tundra to boreal forest
C. Thompson, J. Beringer, F. S. Chapin III, A. D. McGuire
2004, Journal of Vegetation Science (15) 397-406
Question: Current climate changes in the Alaskan Arctic, which are characterized by increases in temperature and length of growing season, could alter vegetation structure, especially through increases in shrub cover or the movement of treeline. These changes in vegetation structure have consequences for the climate system. What is the relationship...
Subsurface fate of spilled petroleum hydrocarbons in continuous permafrost
K. McCarthy, L. Walker, L. Vigoren
2004, Cold Regions Science and Technology (38) 43-54
Accidental releases of approximately 2000 m3 of fuel have resulted in subsurface contamination adjacent to Imikpuk Lake, a drinking-water source near Barrow, AK. This paper presents a conceptual model of the distribution and transport of subsurface free-phase hydrocarbons at this site. The mean annual temperature in Barrow is -13 ??C,...
Exposure to perchlorate induces the formation of macrophage aggregates in the trunk kidney of zebrafish and mosquitofish
T. Capps, S. Mukhi, J.J. Rinchard, C.W. Theodorakis, V. S. Blazer, R. Patino
2004, Journal of Aquatic Animal Health (16) 145-151
Environmental contamination of ground and surface waters by perchlorate, derived from ammonium perchlorate (AP) and other perchlorate salts, is of increasing concern. Exposure to perchlorate can impair the thyroid endocrine system, which is thought to modulate renal and immune function in vertebrates. This study with zebrafish Danio rerio and eastern...
