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Page 1226, results 30626 - 30650

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Publication Extents

Not all publications have extents, not all extents are completely accurate
The upper bound of Pier Scour defined by selected laboratory and field data
Stephen Benedict, Andral W. Caldwell
2015, Conference Paper
The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted several field investigations of pier scour in South Carolina (Benedict and Caldwell, 2006; Benedict and Caldwell, 2009) and used that data to develop envelope curves defining the upper bound of pier scour. To expand upon this...
Inaccuracies in sediment budgets arising from estimations of tributary sediment inputs: an example from a monitoring network on the southern Colorado plateau
Ronald E. Griffiths, David J. Topping
2015, Conference Paper
Sediment budgets are an important tool for understanding how riverine ecosystems respond to perturbations. Changes in the quantity and grain-size distribution of sediment within river systems affect the channel morphology and related habitat resources. It is therefore important for resource managers to know if a channel reach is in a...
Characterizing and simulating sediment loads and transport in the lower part of the San Antonio River Basin
J. Ryan Banta, Darwin J. Ockerman, Cassi Crow, Stephen P. Opsahl
2015, Conference Paper
This extended abstract is based on the U.S. Geological Survey Scientific Investigations Reports by Crow et al. (2013) and Banta and Ockerman (2014). Suspended sediment in rivers and streams can play an important role in ecological health of rivers and estuaries and consequently is an important issue for water-resource managers....
From mobile ADCP to high-resolution SSC: a cross-section calibration tool
Justin A. Boldt
2015, Conference Paper
Sediment is a major cause of stream impairment, and improved sediment monitoring is a crucial need. Point samples of suspended-sediment concentration (SSC) are often not enough to provide an understanding to answer critical questions in a changing environment. As technology has improved, there now exists the opportunity to obtain discrete...
Gully annealing by fluvially-sourced Aeolian sand: remote sensing investigations of connectivity along the Fluvial-Aeolian-hillslope continuum on the Colorado River
Joel B. Sankey, Amy E. East, Brian D. Collins, Joshua J. Caster
2015, Conference Paper, Proceedings of the Joint Federal Interagency Conference 2015
Processes contributing to development of ephemeral gully channels are of great importance to landscapes worldwide, and particularly in dryland regions where soil loss and land degradation from gully erosion pose long-term, land-management problems. Whereas gully formation has been relatively well studied, much less is known of the processes that anneal...
Sublethal red tide toxin exposure in free-ranging manatees (Trichechus manatus) affects the immune system through reduced lymphocyte proliferation responses, inflammation, and oxidative stress
C.J. Walsh, M. Butawan, J. Yordy, R. Ball, M. de Witt, Robert K. Bonde
2015, Aquatic Toxicology (161) 73-84
The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected by exposure to blooms of the toxic dinoflagellate, Karenia brevis. K. brevis blooms are common in manatee habitats of Florida's southwestern coast and produce a group of cyclic polyether toxins collectively referred to as red tide toxins, or...
Rhenium: a rare metal critical in modern transportation
David A. John
2015, Fact Sheet 2014-3101
Rhenium is a silvery-white, metallic element with an extremely high melting point (3,180 degrees Celsius) and a heat-stable crystalline structure, making it exceptionally resistant to heat and wear. Since the late 1980s, rhenium has been critical for superalloys used in turbine blades and in catalysts used to produce lead-free gasoline. One...
Fine-scale pathways used by adult sea lampreys during riverine spawning migrations
Christopher Holbrook, Roger A. Bergstedt, Noah S. Adams, Tyson Hatton, Robert L. McLaughlin
2015, Transactions of the American Fisheries Society (144) 549-562
Better knowledge of upstream migratory patterns of spawning Sea Lampreys Petromyzon marinus, an invasive species in the Great Lakes, is needed to improve trapping for population control and assessment. Although trapping of adult Sea Lampreys provides the basis for estimates of lake-wide abundance that are used to evaluate the Sea...
Tellurium: providing a bright future for solar energy
Richard J. Goldfarb
2015, Fact Sheet 2014-3077
Tellurium is one of the least common elements on Earth. Most rocks contain an average of about 3 parts per billion tellurium, making it rarer than the rare earth elements and eight times less abundant than gold. Grains of native tellurium appear in rocks as a brittle, silvery-white material, but...
Translocation of Humpback Chub into tributary streams of the Colorado River: Implications for conservation of large-river fishes
Jonathan J. Spurgeon, Craig P. Paukert, Brian D. Healy, Melissa Trammell, Dave Speas, Emily Omana Smith
2015, Transactions of the American Fisheries Society (144) 502-514
The Humpback Chub Gila cypha, a large-bodied, endangered cyprinid endemic to the Colorado River basin, is in decline throughout most of its range due largely to anthropogenic factors. Translocation of Humpback Chub into tributaries of the Colorado River is one conservation activity that may contribute to the expansion of the species’...
Climate trends and projections for Guam
Stephen B. Gingerich, Victoria Keener, Melissa L. Finucane
2015, Report
The island of Guam experiences a tropical marine climate, which is warm and humid moderated by seasonal tradewinds and a wet and dry season. The dry season lasts from January to June, while the rainy months are from July to December. Annual rainfall totals 84-116 inches (2133-2946 mm), of which...
Alternative standardization approaches to improving streamflow reconstructions with ring-width indices of riparian trees
David M. Meko, Jonathan M. Friedman, Ramzi Touchan, Jesse R. Edmondson, Eleanor R. Griffin, Julian A. Scott
2015, The Holocene (25) 1093-1101
Old, multi-aged populations of riparian trees provide an opportunity to improve reconstructions of streamflow. Here, ring widths of 394 plains cottonwood (Populus deltoids, ssp. monilifera) trees in the North Unit of Theodore Roosevelt National Park, North Dakota, are used to reconstruct streamflow along the Little Missouri River (LMR), North Dakota,...
Water quality of groundwater and stream base flow in the Marcellus Shale Gas Field of the Monongahela River Basin, West Virginia, 2011-12
Douglas B. Chambers, Mark D. Kozar, Terence Messinger, Michon L. Mulder, Adam J. Pelak, Jeremy S. White
2015, Scientific Investigations Report 2014-5233
The Marcellus Shale gas field underlies portions of New York, Pennsylvania, Ohio, Virginia, Maryland, Tennessee, and West Virginia. Development of hydraulic fracturing and horizontal drilling technology led to extensive development of gas from the Marcellus Shale beginning about 2007. The need to identify and monitor changes in water-quality conditions related...
Landsat surface reflectance data
Water Resources Division, U.S. Geological Survey
2015, Fact Sheet 2015-3034
Landsat satellite data have been produced, archived, and distributed by the U.S. Geological Survey since 1972. Users rely on these data for historical study of land surface change and require consistent radiometric data processed to the highest science standards. In support of the guidelines established through the Global Climate Observing...
Land-use impacts on water resources and protected areas: applications of state-and-transition simulation modeling of future scenarios
Tamara Wilson, Benjamin M. Sleeter, Jason T. Sherba, Dick Cameron
2015, Conference Paper, AIMS Environmental Science
Human land use will increasingly contribute to habitat loss and water shortages in California, given future population projections and associated land-use demand. Understanding how land-use change may impact future water use and where existing protected areas may be threatened by land-use conversion will be important if effective, sustainable management approaches...
Community ecology in a changing environment: Perspectives from the Quaternary
Stephen T. Jackson, Jessica L. Blois
2015, PNAS (112) 4915-4921
Community ecology and paleoecology are both concerned with the composition and structure of biotic assemblages but are largely disconnected. Community ecology focuses on existing species assemblages and recently has begun to integrate history (phylogeny and continental or intercontinental dispersal) to constrain community processes. This division has left a “missing middle”:...
Dynamic triggering
David P. Hill, Stephanie Prejean
Gerald Schubert, editor(s)
2015, Book chapter, Volume 4 of <i>Treatise on Geophysics</i> (Second Edition)
Dynamic stresses propagating as seismic waves from large earthquakes trigger a spectrum of responses at global distances. In addition to locally triggered earthquakes in a variety of tectonic environments, dynamic stresses trigger tectonic (nonvolcanic) tremor in the brittle–plastic transition zone along major plate-boundary faults, activity changes in hydrothermal and volcanic...
Organic sedimentation in modern lacustrine systems: A case study from Lake Malawi, East Africa
Geoffrey S. Ellis, Barry J. Katz, Christopher A. Scholz, Peter K. Swart
2015, Special Paper of the Geological Society of America (515) 19-47
This study examines the relationship between depositional environment and sedimentary organic geochemistry in Lake Malawi, East Africa, and evaluates the relative significance of the various processes that control sedimentary organic matter (OM) in lacustrine systems. Total organic carbon (TOC) concentrations in recent sediments from Lake Malawi range from 0.01 to...
Effects and empirical critical loads of Nitrogen for ecoregions of the United States
Linda H. Pardo, Molly J. Robin-Abbott, Mark E. Fenn, Christine L. Goodale, Linda H. Geiser, Charles T. Driscoll, Edith B. Allen, Jill Baron, Roland Bobbink, William D. Bowman, C M Clark, B. Emmett, Frank S Gilliam, Tara L. Greaver, Sharon J Hall, Erik A. Lilleskov, Lingli Liu, Jason A. Lynch, Knute J Nadelhoffer, Steven Perakis, John L Stoddard, Kathleen C. Weathers, Robin L. Dennis
2015, Book chapter, Critical loads and dynamic risk assessments
Human activity in the last century has increased nitrogen (N) deposition to a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. We synthesized current research relating atmospheric N deposition to effects on terrestrial and freshwater ecosystems...
Physical abrasion of mafic minerals and basalt grains: application to Martian aeolian deposits
Carin Cornwall, Joshua L. Bandfield, Timothy N. Titus, B. C. Schreiber, D. R. Montgomery
2015, Icarus (256) 13-21
Sediment maturity, or the mineralogical and physical characterization of sediment deposits, has been used to locate sediment source, transport medium and distance, weathering processes, and paleoenvironments on Earth. Mature terrestrial sands are dominated by quartz, which is abundant in source lithologies on Earth and is physically and chemically stable under...
Turbines and terrestrial vertebrates: variation in tortoise survivorship between a wind energy facility and an adjacent undisturbed wildland area in the desert southwest (USA)
Mickey Agha, Jeffrey E. Lovich, Joshua R. Ennen, Benjamin J. Augustine, Terence R. Arundel, Mason O. Murphy, Kathie Meyer-Wilkins, Curtis Bjurlin, David F. Delaney, Jessica Briggs, Meaghan Austin, Sheila V. Madrak, Steven J. Price
2015, Environmental Management (56) 332-341
With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's...
Minerals, lands, and geology for the common defence and general welfare, Volume 4, 1939-1961: A history of geology in relation to the development of public-land, federal science, and mapping policies and the development of mineral resources in the United States from the 60th to the 82d year of the U.S. Geological Survey
Mary C. Rabbitt, Clifford M. Nelson
2015, Book
The fourth volume of the comprehensive history of the U.S. Geological Survey (USGS) is titled “Minerals, Lands, and Geology for the Common Defence and General Welfare—Volume 4, 1939‒1961.” The title is based on a passage in the preamble of the U.S. Constitution. The late Mary C. Rabbitt (1915‒2002), a geophysicist who...
Application of the FluEgg model to predict transport of Asian carp eggs in the Saint Joseph River (Great Lakes tributary)
Tatiana Garcia, Elizabeth A. Murphy, P. Ryan Jackson, Marcelo H. Garcia
2015, Journal of Great Lakes Research (41) 374-386
The Fluvial Egg Drift Simulator (FluEgg) is a three-dimensional Lagrangian model that simulates the movement and development of Asian carp eggs until hatching based on the physical characteristics of the flow field and the physical and biological characteristics of the eggs. This tool provides information concerning egg development and spawning...
Environmental DNA (eDNA) sampling improves occurrence and detection estimates of invasive Burmese pythons
Margaret E. Hunter, Sara J. Oyler-McCance, Robert M. Dorazio, Jennifer A. Fike, Brian J. Smith, Charles T. Hunter, Robert N. Reed, Kristen M. Hart
2015, PLoS ONE (10)
Environmental DNA (eDNA) methods are used to detect DNA that is shed into the aquatic environment by cryptic or low density species. Applied in eDNA studies, occupancy models can be used to estimate occurrence and detection probabilities and thereby account for imperfect detection. However, occupancy terminology has been applied inconsistently...