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Page 1877, results 46901 - 46925

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Not all publications have extents, not all extents are completely accurate
Regional estimates of ecological services derived from U.S. Department of Agriculture conservation programs in the Mississippi Alluvial Valley
Stephen P. Faulkner, Michael J. Baldwin, Wylie C. Barrow, Hardin Waddle, Bobby D. Keeland, Susan C. Walls, Dale James, Tom Moorman
2010, Report, NRCS
The Mississippi Alluvial Valley (MAV) is the Nation?s largest floodplain and this once predominantly forested ecosystem provided significant habitat for a diverse flora and fauna, sequestered carbon in trees and soil, and stored floodwater, sediments, and nutrients within the floodplain. This landscape has been substantially altered by the conversion of...
Reserve growth in oil pools of Alberta: Model and forecast
M. Verma, T. Cook
2010, Bulletin of Canadian Petroleum Geology (58) 283-293
Reserve growth is recognized as a major component of additions to reserves in most oil provinces around the world, particularly in mature provinces. It takes place as a result of the discovery of new pools/reservoirs and extensions of known pools within existing fields, improved knowledge of reservoirs over time leading...
Effects of lipid extraction on stable isotope ratios in avian egg yolk: Is arithmetic correction a reliable alternative?
S. Oppel, R.N. Federer, D. M. O’Brien, A.N. Powell, Tuula E. Hollmén
2010, The Auk (127) 72-78
Many studies of nutrient allocation to egg production in birds use stable isotope ratios of egg yolk to identify the origin of nutrients. Dry egg yolk contains >50% lipids, which are known to be depleted in 13C. Currently, researchers remove lipids from egg yolk using a chemical lipid-extraction procedure before...
On the nature of the dirty ice at the bottom of the GISP2 ice core
Michael L. Bender, Edward Burgess, Richard B. Alley, Bruce Barnett, Gary D. Clow
2010, Earth and Planetary Science Letters (299) 466-473
We present data on the triple Ar isotope composition in trapped gas from clean, stratigraphically disturbed ice between 2800 and 3040m depth in the GISP2 ice core, and from basal dirty ice from 3040 to 3053m depth. We also present data for the abundance and isotopic composition of O2 and...
A general science-based framework for dynamical spatio-temporal models
C. K. Wikle, M.B. Hooten
2010, Test (19) 417-451
Spatio-temporal statistical models are increasingly being used across a wide variety of scientific disciplines to describe and predict spatially-explicit processes that evolve over time. Correspondingly, in recent years there has been a significant amount of research on new statistical methodology for such models. Although descriptive models that approach the problem...
Repeated use of an abandoned vehicle by nesting Turkey vultures (Cathartes aura)
L.D. Igl, S.L. Peterson
2010, Journal of Raptor Research (44) 73-75
Turkey Vultures (Cathartes aura) lay their eggs on an existing substrate in the dark recesses of a variety of natural sites (Kirk and Mossman 1998). Although an important requirement of Turkey Vulture nest-site selection is isolation from human disturbances (<a class="ref"...
Complex adaptive systems and game theory: An unlikely union
M. Hadzikadic, T. Carmichael, C. Curtin
2010, Complexity (16) 34-42
A Complex Adaptive System is a collection of autonomous, heterogeneous agents, whose behavior is defined with a limited number of rules. A Game Theory is a mathematical construct that assumes a small number of rational players who have a limited number of actions or strategies available to them. The CAS...
Shallow magma accumulation at Kīlauea Volcano, Hawai‘i, revealed by microgravity surveys
Daniel J. Johnson, Albert A. Eggers, Marco Bagnardi, Maurizio Battaglia, Michael P. Poland, Asta Miklius
2010, Geology (38) 1139-1142
Using microgravity data collected at Kīlauea Volcano, Hawai‘i (United States), between November 1975 and January 2008, we document significant mass increase beneath the east margin of Halema‘uma‘u Crater, within Kīlauea's summit caldera. Surprisingly, there was no sustained uplift accompanying the mass accumulation. We propose that the positive gravity residual in...
Hurricane storm surge and amphibian communities in coastal wetlands of northwestern Florida
Margaret S. Gunzburger, William B. Hughes, William J. Barichivich, Jennifer S. Staiger
2010, Wetlands Ecology and Management (18) 651-663
Isolated wetlands in the Southeastern United States are dynamic habitats subject to fluctuating environmental conditions. Wetlands located near marine environments are subject to alterations in water chemistry due to storm surge during hurricanes. The objective of our study was to evaluate the effect of storm surge overwash on wetland amphibian...
Inverted channel deposits on the floor of Miyamoto crater, Mars
Horton E. Newsom, Nina L. Lanza, Ann M. Ollila, Sandra M. Wiseman, Ted L. Roush, Giuseppe A. Marzo, Livio L. Tornabene, Chris H. Okubo, Mikki M. Osterloo, Victoria E. Hamilton, Larry S. Crumpler
2010, Icarus (205) 64-72
Morphological features on the western floor of Miyamoto crater in southwestern Meridiani Planum, Mars, are suggestive of past fluvial activity. Imagery from the High Resolution Imaging Science Experiment (HiRISE) gives a detailed view of raised curvilinear features that appear to represent inverted paleochannel deposits. The inverted terrain appears to be...
Arsenic Geochemistry and Hydrostratigraphy in Midwestern U.S. Glacial Deposits
Terry L. Root, M.B. Gotkowitz, J.M. Bahr, J.W. Attig
2010, Ground Water (48) 903-912
Arsenic concentrations exceeding the U.S. EPA's 10 ??g/L standard are common in glacial aquifers in the midwestern United States. Previous studies have indicated that arsenic occurs naturally in these aquifers in association with metal-(hydr)oxides and is released to groundwater under reducing conditions generated by microbial oxidation of organic matter. Despite...
Long-term reductions in anthropogenic nutrients link to improvements in Chesapeake Bay habitat
H. Ruhl, N. B. Rybicki
2010, Proceedings of the National Academy of Sciences of the United States of America (107) 16566-16570
Great effort continues to focus on ecosystem restoration and reduction of nutrient inputs thought to be responsible, in part, for declines in estuary habitats worldwide. The ability of environmental policy to address restoration is limited, in part, by uncertainty in the relationships between costly restoration and benefits. Here, we present...
Carbon dioxide on the satellites of Saturn: Results from the Cassini VIMS investigation and revisions to the VIMS wavelength scale
D. P. Cruikshank, A.W. Meyer, R. H. Brown, R. N. Clark, R. Jaumann, K. Stephan, C. A. Hibbitts, S.A. Sandford, R.M.E. Mastrapa, G. Filacchione, C.M.D. Ore, P. D. Nicholson, B. J. Buratti, T. B. McCord, R.M. Nelson, J.B. Dalton, K. H. Baines, D. L. Matson
2010, Icarus (206) 561-572
Several of the icy satellites of Saturn show the spectroscopic signature of the asymmetric stretching mode of C-O in carbon dioxide (CO2) at or near the nominal solid-phase laboratory wavelength of 4.2675 ??m (2343.3 cm-1), discovered with the Visible-Infrared Mapping Spectrometer (VIMS) on the Cassini spacecraft. We report here on...
Climate change threatens polar bear populations: A stochastic demographic analysis
C.M. Hunter, H. Caswell, M.C. Runge, E.V. Regehr, Steven C. Amstrup, I. Stirling
2010, Ecology (91) 2883-2897
The polar bear (Ursus maritimus) depends on sea ice for feeding, breeding, and movement. Significant reductions in Arctic sea ice are forecast to continue because of climate warming. We evaluated the impacts of climate change on polar bears in the southern Beaufort Sea by means of a demographic analysis, combining...
Reptile and amphibian responses to large-scale wildfires in southern California
C.J. Rochester, C.S. Brehme, D.R. Clark, D.C. Stokes, S.A. Hathaway, Robert N. Fisher
2010, Journal of Herpetology (44) 333-351
In 2003, southern California experienced several large fires that burned thousands of hectares of wildlife habitats and conserved lands. To investigate the effects of these fires on the reptile and amphibian communities, we compared the results from prefire herpetofauna and vegetation sampling to two years of postfire sampling across 38...
Rapid climatic signal propagation from source to sink in a southern California sediment-routing system
J.A. Covault, B.W. Romans, A. Fildani, M. McGann, S.A. Graham
2010, Journal of Geology (118) 247-259
Terrestrial source areas are linked to deep-sea basins by sediment-routing systems, which only recently have been studied with a holistic approach focused on terrestrial and submarine components and their interactions. Here we compare an extensive piston-core and radiocarbon-age data set from offshore southern California to contemporaneous Holocene climate proxies in...
Modelling detection probabilities to evaluate management and control tools for an invasive species
M.T. Christy, A. A. Yackel Adams, G.H. Rodda, J. A. Savidge, C.L. Tyrrell
2010, Journal of Applied Ecology (47) 106-113
For most ecologists, detection probability (p) is a nuisance variable that must be modelled to estimate the state variable of interest (i.e. survival, abundance, or occupancy). However, in the realm of invasive species control, the rate of detection and removal is the rate-limiting step for management of this pervasive environmental...
The Paleogene California River: Evidence of Mojave-Uinta paleodrainage from U-Pb ages of detrital zircons
S.J. Davis, W.R. Dickinson, G. E. Gehrels, J.E. Spencer, T.F. Lawton, A.R. Carroll
2010, Geology (38) 931-934
U-Pb age spectra of detrital zircons in samples from the Paleogene Colton Formation in the Uinta Basin of northeastern Utah and the Late Cretaceous McCoy Mountains Formation of southwestern Arizona (United States) are statistically indistinguishable. This finding refutes previous inferences that arkosic detritus of the Colton was derived from cratonic...
Assessment of undiscovered conventional oil and gas resources, onshore Claiborne Group, United Statespart of the northern Gulf of Mexico Basin
P.C. Hackley, T.E. Ewing
2010, American Association of Petroleum Geologists Bulletin (94) 1607-1636
The middle Eocene Claiborne Group was assessed for undiscovered conventional hydrocarbon resources using established U.S. Geological Survey assessment methodology. This work was conducted as part of a 2007 assessment of Paleogene-Neogene strata of the northern Gulf of Mexico Basin, including the United States onshore and state waters (Dubiel et al.,...
Assessment of basin-scale hydrologic impacts of CO2 sequestration, Illinois basin
M. Person, A. Banerjee, J. Rupp, C. Medina, P. Lichtner, C. Gable, R. Pawar, M. Celia, J. McIntosh, V. Bense
2010, International Journal of Greenhouse Gas Control (4) 840-854
Idealized, basin-scale sharp-interface models of CO2 injection were constructed for the Illinois basin. Porosity and permeability were decreased with depth within the Mount Simon Formation. Eau Claire confining unit porosity and permeability were kept fixed. We used 726 injection wells located near 42 power plants to deliver 80 million metric...
Rate of formation and dissolution of mercury sulfide nanoparticles: The dual role of natural organic matter
Aaron J. Slowey
2010, Geochimica et Cosmochimica Acta (74) 4693-4708
Mercury is a global contaminant of concern due to its transformation by microorganisms to form methylmercury, a toxic species that accumulates in biological tissues. The effect of dissolved organic matter (DOM) isolated from natural waters on reactions between mercury(II) (Hg) and sulfide (S(-II)) to form HgS(s) nanoparticles across a range...
Environmental controls on drainage behavior of an ephemeral stream
K.W. Blasch, T.P.A. Ferre, J.A. Vrugt
2010, Stochastic Environmental Research and Risk Assessment (24) 1077-1087
Streambed drainage was measured at the cessation of 26 ephemeral streamflow events in Rillito Creek, Tucson, Arizona from August 2000 to June 2002 using buried time domain reflectometry (TDR) probes. An unusual drainage response was identified, which was characterized by sharp drainage from saturation to near field capacity at each...
Tidal freshwater wetland herbivory in Anacostia Park
Cairn Krafft, Jeff S. Hatfield, Richard S. Hammerschlag
2010, Natural Resource Technical Report NPS/NCR/NCRO/NRTR2010/002
Herbivory has played a major role in dictating vegetation abundance and species composition at Kingman Marsh in Anacostia Park, Washington, D.C., since restoration of this tidal freshwater wetland was initiated in 2000. In June 2009 an herbivory study was established to document the impacts of resident Canada goose (Branta canadensis...
Growth, condition factor, and bioenergetics modeling link warmer stream temperatures below a small dam to reduced performance of juvenile steelhead
S.T. Sauter, P.J. Connolly
2010, Northwest Science (84) 369-377
We investigated the growth and feeding performance of juvenile steelhead Oncorhynchus mykiss using field measures and bioenergetics modeling. Juvenile steelhead populations were sampled from mid-June through August 2004 at study sites upstream and downstream of Hemlock Dam. The growth and diet of juvenile steelhead were determined for a warm (summer)...
Constructing an interdisciplinary flow regime recommendation
J.M. Bartholow
2010, Journal of the American Water Resources Association (46) 892-906
It is generally agreed that river rehabilitation most often relies on restoring a more natural flow regime, but credibly defining the desired regime can be problematic. I combined four distinct methods to develop and refine month-by-month and event-based flow recommendations to protect and partially restore the ecological integrity of the...