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Page 1518, results 37926 - 37950

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Geologic model for the assessment of undiscovered hydrocarbons in Lower to Upper Cretaceous carbonate rocks of the Fredericksburg and Washita groups, U.S. Gulf Coast Region
Sharon M. Swanson, Catherine B. Enomoto, Kristin O. Dennen, Brett J. Valentine, Celeste D. Lohr
2013, Gulf Coast Association of Geological Societies Transactions (63) 423-437
As part of the assessment of undiscovered oil and gas resources in Jurassic and Cretaceous strata of the U.S. Gulf Coast in 2010, the U.S. Geological Survey assessed carbonate rocks of the Fredericksburg and Washita groups and their equivalent units underlying onshore lands and State waters. One conventional assessment unit...
Historical methane hydrate project review
Timothy Collett, Jang-Jun Bahk, Matt Frye, Dave Goldberg, Jarle Husebo, Carolyn Koh, Mitch Malone, Craig Shipp, Marta Torres
2013, Report
In 1995, U.S. Geological Survey made the first systematic assessment of the volume of natural gas stored in the hydrate accumulations of the United States. That study, along with numerous other studies, has shown that the amount of gas stored as methane hydrates in the world greatly exceeds the volume...
Food availability in exotic grasslands: a potential mechanism for depauperate breeding assemblages
Andrew D. George, Timothy J. O’Connell, Karen R. Hickman, David M. Leslie Jr.
2013, Wilson Journal of Ornithology (125) 526-533
We investigated the influence of Old World bluestem (Bothriochloa ischaemum; OWB) monocultures on grassland bird abundance through analysis of vegetation structure and food availability. We compared breeding bird density, vegetation structure and composition, and arthropod biomass between six native grass and six OWB fields in the southern Great Plains. The...
Combining glyphosate with burning or mowing improves control of Yellow Bluestem (Bothriochloa ischaemum)
S. Robertson, Karen R. Hickman, Keith R. Harmoney, David M. Leslie Jr.
2013, Rangeland Ecology and Management (66) 376-381
The invasive yellow bluestem (Bothriochloa ischaemum [L.] Keng) threatens native biodiversity, and its control is of interest to land managers involved in restoration of invaded grasslands. We used single, double, and triple applications of glyphosate (2.125 kg ai.ha-1.application-1) over the course of one growing season in combinations at different timings...
Maintaining and restoring sustainable ecosystems in southern Nevada
Jeanne C. Chambers, Burton K. Pendleton, Donald W. Sada, Steven M. Ostoja, Matthew L. Brooks
2013, General Technical Report RMRS-GTR-303-7
Managers in southern Nevada are challenge with determining appropriate goals and objectives and developing viable approaches for maintaining and restoring sustainable ecosystems in a time of rapid socio-ecological and environmental change. Sustainable or "healthy" ecosystems supply clean air, water and habitat for a diverse array of plants and animals. As...
Public release of the ISC-GEM Global Instrumental Earthquake Catalogue (1900-2009)
Dmitry A. Storchak, Domenico Di Giacomo, Istvan Bondara, E. Robert Engdahl, James Harris, William H.K. Lee, Antonio Villaseñor, Peter Bormann
2013, Seismological Research Letters (84) 810-815
The International Seismological Centre–Global Earthquake Model (ISC–GEM) Global Instrumental Earthquake Catalogue (1900–2009) is the result of a special effort to substantially extend and improve currently existing global catalogs to serve the requirements of specific user groups who assess and model seismic hazard and risk. The data from the ISC–GEM Catalogue...
Modeling groundwater flow and quality
Leonard F. Konikow, Pierre D. Glynn
Olle Selinus, editor(s)
2013, Book chapter, Essentials of medical geology
In most areas, rocks in the subsurface are saturated with water at relatively shallow depths. The top of the saturated zone—the water table—typically occurs anywhere from just below land surface to hundreds of feet below the land surface. Groundwater generally fills all pore spaces below the water table and is...
Adaptive harvest management for the Svalbard population of pink-footed geese: cooperator report
Fred A. Johnson, Gitte H. Jensen, Jesper Madsen
2013, Report
This document describes progress to date on the development of a harvest‐management strategy for maintaining pink‐footed goose abundance near their target level by providing for sustainable harvests in Norway and Denmark. Many goose populations in western Europe have increased dramatically in recent decades. The Svalbard population of pink‐footed geese (Anser brachyrhynchus) is a good...
Export of dissolved organic carbon from the Penobscot River basin in north-central Maine
Thomas G. Huntington, George R. Aiken
2013, Journal of Hydrology (476) 244-256
Dissolved organic carbon (DOC) flux from the Penobscot River and its major tributaries in Maine was determined using continuous discharge measurements, discrete water sampling, and the LOADEST regression software. The average daily flux during 2004–2007 was 71 kg C ha−1 yr−1 (392 Mt C d−1), an amount larger than measured...
How not to find a wolf den
L. David Mech
2013, International Wolf (23) 4-7
A five-day odyssey, spanning 58 hours without decent sleep or meals, taught these researchers one thing-how not to find a wolf den....
Potential effects of climate change on inland glacial lakes and implications for lake-dependent biota in Wisconsin: final report April 2013
Michael W. Meyer, John F. Walker, Kevin P. Kenow, Paul W. Rasmussen, Paul J. Garrison, Paul C. Hanson, Randall J. Hunt
2013, Report
The economic vitality and quality of life of many northern Wisconsin communities is closely associated with the ecological condition of the abundant water resources in the region. Climate change models predict warmer temperatures, changes to precipitation patterns, and increased evapotranspiration in the Great Lakes region. Recently (1950-2006), many regions of...
Spatial extent and dynamics of dam impacts on tropical island freshwater fish assemblages
Patrick B. Cooney, Thomas J. Kwak
2013, BioScience (63) 176-190
Habitat connectivity is vital to the persistence of migratory fishes. Native tropical island stream fish assemblages composed of diadromous species require intact corridors between ocean and riverine habitats. High dams block fish migration, but low-head artificial barriers are more widespread and are rarely assessed for impacts. Among all 46 drainages...
2D IR spectra of cyanide in water investigated by molecular dynamics simulations
Myung Won Lee, Joshua K. Carr, Michael Gollner, Peter Hamm, Markus Meuwly
2013, Journal of Chemical Physics (139) 1-12
Using classical molecular dynamics simulations, the 2D infrared (IR) spectroscopy of CN− solvated in D2O is investigated. Depending on the force field parametrizations, most of which are based on multipolar interactions for the CN− molecule, the frequency-frequency correlation function and observables computed from it differ. Most notably, models based on...
Species of conservation concern and environmental stressors: Local regional and global effects
Steven M. Ostoja, Matthew L. Brooks, Jeanne C. Chambers, Burton Pendleton
2013, General Technical Report RMRS-GTR-303-6
Species conservation has traditionally been based on individual species within the context of their requisite habitat, which is generally defined as the communities and ecosystems deemed necessary for their presence. Conservation decisions are hampered by the fact that environmental stressors that poetically threaten the persistence of species can operate at...
Microsatellites indicate minimal barriers to mule deer Odocoileus hemionus dispersal across Montana, USA
John H. Powell, Steven T. Kalinowski, Megan D. Higgs, Michael R. Ebinger, Ninh V. Vu, Paul C. Cross
2013, Wildlife Biology (19) 102-110
To better understand the future spread of chronic wasting disease, we conducted a genetic assessment of mule deer Odocoileus hemionus population structure across the state of Montana, USA. Individual based analyses were used to test for population structure in the absence of a priori designations of population membership across the sampling area. Samples from...
Effects of hydrologic connectivity on aquatic macroinvertebrate assemblages in different marsh types
Sung-Ryong Kang, Sammy L. King
2013, Aquatic Biology (18) 149-160
Hydrologic connectivity can be an important driver of aquatic macroinvertebrate assemblages. Its effects on aquatic macroinvertebrate assemblages in coastal marshes, however, are relatively poorly studied. We evaluated the effects of lateral hydrologic connectivity (permanently connected ponds: PCPs; temporary connected ponds: TCPs), and other environmental variables on aquatic macroinvertebrate assemblages and...
Juvenile i`iwi detected in lower elevations of Hawaii Volcanoes National Park
Jacqueline M. Gaudioso, Angela T. Beck
2013, Report, NPS web page
The Hawaiian islands are home to a diverse array of plants and animals found nowhere else on Earth. Among the most famous of these are the spectacular Hawaiian honeycreepers, a group that evolved from a single flock of ancestral finches into at least 54 unique species. Unfortunately, the same isolation...
Clustering of GPS velocities in the Mojave Block, southeastern California
James C. Savage, Robert W. Simpson
2013, Journal of Geophysical Research B: Solid Earth (118) 1747-1759
We find subdivisions within the Mojave Block using cluster analysis to identify groupings in the velocities observed at GPS stations there. The clusters are represented on a fault map by symbols located at the positions of the GPS stations, each symbol representing the cluster to which the velocity of that...
Impacts of golden alga Prymnesium parvum on fish populations in reservoirs of the upper Colorado River and Brazos River basins, Texas
Matthew M. VanLandeghem, Mukhtar Farooqi, B. Farquhar, Reynaldo Patino
2013, Transactions of the American Fisheries Society (142) 581-595
Several reservoirs in the upper Colorado River and Brazos River basins in Texas have experienced toxic blooms of golden alga Prymnesium parvum and associated fish kills since 2001. There is a paucity of information, however, regarding the population-level effects of such kills in large reservoirs, species-specific resistance to or recovery...
Reactive transport modeling at uranium in situ recovery sites: uncertainties in uranium sorption on iron hydroxides
Raymond H. Johnson, Hlanganani Tutu
Adrian Brown, Linda Figueroa, Christian Wolkersdorfer, editor(s)
2013, Conference Paper, Annual International Mine Water Association Conference: Reliable Mine Water Technology
Geochemical changes that can occur down gradient from uranium in situ recovery (ISR) sites are important for various stakeholders to understand when evaluating potential effects on surrounding groundwater quality. If down gradient solid-phase material consists of sandstone with iron hydroxide coatings (no pyrite or organic carbon), sorption of uranium on...
Focused ion beam and field-emission microscopy of metallic filaments in memory devices based on thin films of an ambipolar organic compound consisting of oxadiazole, carbazole, and fluorene units
Christopher Pearson, Leon Bowen, Myung Won Lee, Alison L. Fisher, Katherine E. Linton, Martin R. Bryce, Michael C. Petty
2013, Applied Physics Letters (102)
We report on the mechanism of operation of organic thin film resistive memory architectures based on an ambipolar compound consisting of oxadiazole, carbazole, and fluorene units. Cross-sections of the devices have been imaged by electron microscopy both before and after applying a voltage. The micrographs reveal the growth of filaments,...
Three new species of Coccidia (Apicomplexa: Eimeriidae) from Skinks, Lipinia spp. (Sauria: Scincidae), from Oceania
Chris T. McAllister, Donald W. Duszynski, Christopher C. Austin, Robert N. Fisher
2013, Journal of Parasitology (99) 1086-1088
Between September 1991 and March 1993, 25 moth skinks (Lipinia noctua) were collected from various localities on the Cook Islands, Fiji, Papua New Guinea (PNG), and Vanuatu and examined for coccidians. In addition, a single Roux's lipinia skink (Lipinia rouxi) was collected from PNG and examined for coccidia. Sixteen (64%)...