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Page 1989, results 49701 - 49725

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Not all publications have extents, not all extents are completely accurate
Metals and trace elements in giant garter snakes (Thamnophis gigas) from the Sacramento Valley, California, USA
Glenn D. Wylie, Roger L. Hothem, D.R. Bergen, Lisa L. Martin, Robert J. Taylor, Brianne E. Brussee
2009, Archives of Environmental Contamination and Toxicology (56) 577-587
The giant garter snake (GGS; Thamnophis gigas) is a federally listed threatened species endemic to wetlands of the Central Valley of California. Habitat destruction has been the main factor in the decline of GGS populations, but the effects of contaminants on this species are unknown. To contribute to the...
Forest rodents provide directed dispersal of Jeffrey pine seeds
J.S. Briggs, S.B.V. Wall, S.H. Jenkins
2009, Ecology (90) 675-687
Some species of animals provide directed dispersal of plant seeds by transporting them nonrandomly to microsites where their chances of producing healthy seedlings are enhanced. We investigated whether this mutualistic interaction occurs between granivorous rodents and Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada by comparing the effectiveness...
Ultraviolet absorbance as a proxy for total dissolved mercury in streams
J.A. Dittman, J. B. Shanley, C. T. Driscoll, G. R. Aiken, A.T. Chalmers, J.E. Towse
2009, Environmental Pollution (157) 1953-1956
Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THgd), DOC concentration and DOC composition, and UV254 absorbance across the three sites over different seasons and flow conditions. Pooling data from...
Predicting fractional bed load transport rates: Application of the Wilcock‐Crowe equations to a regulated gravel bed river
David Gaeuman, E.D. Andrews, Andreas Krause, Wes Smith
2009, Water Resources Research (45)
Bed load samples from four locations in the Trinity River of northern California are analyzed to evaluate the performance of the Wilcock‐Crowe bed load transport equations for predicting fractional bed load transport rates. Bed surface particles become smaller and the fraction of sand on the bed increases with distance downstream...
Rapid middle Miocene collapse of the Mesozoic orogenic plateau in north-central Nevada
Joseph P. Colgan, Christopher D. Henry
2009, International Geology Review (51) 920-961
The modern Sierra Nevada and Great Basin were likely the site of a high-elevation orogenic plateau well into Cenozoic time, supported by crust thickened during Mesozoic shortening. Although crustal thickening at this scale can lead to extension, the relationship between Mesozoic shortening and subsequent formation of the Basin and Range...
Respiratory arsenate reductase as a bidirectional enzyme
C. Richey, P. Chovanec, S.E. Hoeft, R.S. Oremland, P. Basu, J.F. Stolz
2009, Biochemical and Biophysical Research Communications (382) 298-302
The haloalkaliphilic bacterium Alkalilimnicola ehrlichii is capable of anaerobic chemolithoautotrophic growth by coupling the oxidation of arsenite (As(III)) to the reduction of nitrate and carbon dioxide. Analysis of its complete genome indicates that it lacks a conventional arsenite oxidase (Aox), but instead possesses two operons that each encode a putative...
Attempts to identify Clostridium botulinum toxin in milk from three experimentally intoxicated Holstein cows
R.B. Moeller Jr., B. Puschner, R.L. Walker, Tonie E. Rocke, S.R. Smith, J.S. Cullor, A.A. Ardans
2009, Journal of Dairy Science (92) 2529-2533
Three adult lactating Holstein cows were injected in the subcutaneous abdominal vein with 175 ng/kg of body weight of Clostridium botulinum type C toxin (451 cow median toxic doses) to determine if this botulinum toxin crosses the blood–milk barrier. Whole blood (in sodium heparin) and clotted blood serum samples were taken at 0 min,...
Patterns and determinants of mammal species occurrence in India
K.K. Karanth, J.D. Nichols, J.E. Hines, K. U. Karanth, N.L. Christensen
2009, Journal of Applied Ecology (46) 1189-1200
Many Indian mammals face range contraction and extinction, but assessments of their population status are hindered by the lack of reliable distribution data and range maps. 2. We estimated the current geographical ranges of 20 species of large mammals by applying occupancy models to data from country-wide expert. We modelled...
Distribution limits of Batrachochytrium dendrobatidis: a case study in the Rocky Mountains, USA
Blake R. Hossack, Erin L. Muths, Chauncey W. Anderson, Julie D. Kirshtein, P. Stephen Corn
2009, Journal of Wildlife Diseases (45) 1198-1202
Knowledge of the environmental constraints on a pathogen is critical to predicting its dynamics and effects on populations. Batrachochytrium dendrobatidis (Bd), an aquatic fungus that has been linked with widespread amphibian declines, is ubiquitous in the Rocky Mountains. As part of assessing the distribution limits of Bd in our study...
Comparison with CLPX II airborne data using DMRT model
X. Xu, D. Liang, K.M. Andreadis, L. Tsang, E.G. Josberger
2009, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
In this paper, we considered a physical-based model which use numerical solution of Maxwell Equations in three-dimensional simulations and apply into Dense Media Radiative Theory (DMRT). The model is validated in two specific dataset from the second Cold Land Processes Experiment (CLPX II) at Alaska and Colorado. The data were...
Environmental correlates of breeding in the Crested Caracara (Caracara cheriway)
J. L. Morrison, Kyle E. Pias, J.B. Cohen, D.H. Catlin
2009, The Auk (126) 755-764
We evaluated the influence of weather on reproduction of the Crested Caracara (Caracara cheriway) in an agricultural landscape in south-central Florida. We used a mixed logistic-regression modeling approach within an information-theoretic framework to examine the influence of total rainfall, rainfall frequency, and temperature on the number of breeding pairs, timing...
Pliocene three-dimensional global ocean temperature reconstruction
H.J. Dowsett, M.M. Robinson, K.M. Foley
2009, Climate of the Past (5) 769-783
The thermal structure of the mid-Piacenzian ocean is obtained by combining the Pliocene Research, Interpretation and Synoptic Mapping Project (PRISM3) multiproxy sea-surface temperature (SST) reconstruction with bottom water temperature estimates from 27 locations produced using Mg/Ca paleothermometry based upon the ostracod genus Krithe. Deep water temperature estimates are skewed toward...
The moon as a radiometric reference source for on-orbit sensor stability calibration
T.C. Stone
2009, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
The wealth of data generated by the world's Earth-observing satellites, now spanning decades, allows the construction of long-term climate records. A key consideration for detecting climate trends is precise quantification of temporal changes in sensor calibration on-orbit. For radiometer instruments in the solar reflectance wavelength range (near-UV to shortwave-IR), the...
Impacts of acidification on macroinvertebrate communities in streams of the western Adirondack Mountains, New York, USA
Barry P. Baldigo, G.B. Lawrence, R.W. Bode, H. A. Simonin, K. M. Roy, A. J. Smith
2009, Ecological Indicators (9) 226-239
Limited stream chemistry and macroinvertebrate data indicate that acidic deposition has adversely affected benthic macroinvertebrate assemblages in numerous headwater streams of the western Adirondack Mountains of New York. No studies, however, have quantified the effects that acidic deposition and acidification may have had on resident fish and macroinvertebrate communities in...
Migration patterns and wintering range of common loons breeding in the Northeastern United States
K.P. Kenow, D. Adams, N. Schoch, D.C. Evers, W. Hanson, D. Yates, L. Savoy, T.J. Fox, A. Major, R. Kratt, J. Ozard
2009, Waterbirds (32) 234-247
A study, using satellite telemetry, was conducted to determine the precise migration patterns and wintering locations of Common Loons (Gavia immer) breeding in the northeastern United States. Transmitters were implanted in 17 loons (16 adults and one juvenile) that were captured on breeding lakes in New York, New Hampshire, and...
Tamarisk (Tamarix spp.) water fluxes before, during and after episodic defoliation by the saltcedar leaf beetle
K. R. Hultine, P.L. Nagler, P.E. Dennison, S.E. Bush, J.R. Ehleringer
2009, Book, Acta Horticulturae: VII International Workshop on Sap Flow
Tamarisk (Tamarix) species are among the most successful and economically costly plant invaders in the western United States, in part due to its potential to remove large amounts of water from shallow aquifers. Accordingly, local, state and federal agencies have released a new biological control - the saltcedar leaf beetle...
Hand-mouth transfer and potential for exposure to E. coli and F+ coliphage in beach sand, Chicago, Illinois
R.L. Whitman, K. Przybyla-Kelly, D.A. Shively, M.B. Nevers, M.N. Byappanahalli
2009, Journal of Water and Health (7) 623-629
Beach sand contains fecal indicator bacteria, often in densities greatly exceeding the adjacent swimming waters. We examined the transferability of Escherichia coli and F+ coliphage (MS2) from beach sand to hands in order to estimate the potential subsequent health risk. Sand with high initial E. coli concentrations was collected from...
Pre-impact tectonothermal evolution of the crystalline basement-derived rocks in the ICDP-USGS Eyreville B core, Chesapeake Bay impact structure
R.L. Gibson, G.N. Townsend, J. Wright Horton Jr., W.U. Reimold
2009, Special Paper of the Geological Society of America 235-254
Pre-impact crystalline rocks of the lowermost 215 m of the Eyreville B drill core from the Chesapeake Bay impact structure consist of a sequence of pelitic mica schists with subsidiary metagraywackes or felsic metavolcanic rocks, amphibolite, and calc-silicate rock that is intruded by muscovite (??biotite, garnet) granite and granite pegmatite....
Carbon cycling under 300 years of land use change: importance of the secondary vegetation sink
Elena Shevliakova, Stephen W. Pacala, Sergey Malyshev, George C. Hurtt, P. C. D. Milly, John P. Caspersen, Lori T. Sentman, Justin P. Fisk, Christian Wirth, Cyril Crevoisier
2009, Global Biogeochemical Cycles (23)
We have developed a dynamic land model (LM3V) able to simulate ecosystem dynamics and exchanges of water, energy, and CO2 between land and atmosphere. LM3V is specifically designed to address the consequences of land use and land management changes including cropland and pasture dynamics, shifting cultivation, logging, fire, and resulting...
Water velocity and the nature of critical flow in large rapids on the Colorado River, Utah
Christopher S. Magirl, Jeffrey W. Gartner, Graeme M. Smart, Robert H. Webb
2009, Water Resources Research (45)
Rapids are an integral part of bedrock‐controlled rivers, influencing aquatic ecology, geomorphology, and recreational value. Flow measurements in rapids and high‐gradient rivers are uncommon because of technical difficulties associated with positioning and operating sufficiently robust instruments. In the current study, detailed velocity, water surface, and bathymetric data were collected within...
Revised Dst and the epicycles of magnetic disturbance: 1958-2007
J.J. Love, J.L. Gannon
2009, Annales Geophysicae (27) 3101-3131
A revised version of the storm-time disturbance index Dst is calculated using hourly-mean magnetic-observatory data from four standard observatories and collected over the years 1958-2007. The calculation algorithm is a revision of that established by Sugiura et al., and which is now used by the Kyoto World Data Center for...
Hydrologic characterization of desert soils with varying degrees of pedogenesis: 2. Inverse modeling for eff ective properties
B.B. Mirus, K. S. Perkins, J. R. Nimmo, K. Singha
2009, Vadose Zone Journal (8) 496-509
To understand their relation to pedogenic development, soil hydraulic properties in the Mojave Desert were investi- gated for three deposit types: (i) recently deposited sediments in an active wash, (ii) a soil of early Holocene age, and (iii) a highly developed soil of late Pleistocene age. Eff ective parameter values...
Phosphorus and nitrogen legacy in a restoration wetland, upper Klamath lake, Oregon
J.H. Duff, K.D. Carpenter, D.T. Snyder, Karl K. Lee, R.J. Avanzino, F.J. Triska
2009, Wetlands (29) 735-746
The effects of sediment, ground-water, and surface-water processes on the timing, quantity, and mechanisms of N and P fluxes were investigated in the Wood River Wetland 57 years after agricultural practices ceased and seasonal and permanent wetland hydrologies were restored. Nutrient concentrations in standing water largely reflected ground water in...