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Page 1556, results 38876 - 38900

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Wintering waterfowl respond to Wetlands Reserve Program lands in the Central Valley of California
Jeffrey J. Buler, Wylie C. Barrow Jr., Lori A. Randall
2012, Report
Daytime use by wintering waterfowl at Wetlands Reserve Program (WRP) sites within the northern Central Valley of California (CVC) increased dramatically after wetland restoration and was sustained for up to 8 years post-restoration. The magnitude of the increase in waterfowl density at WRP sites after wetland restoration was greater with...
Sensitivity of spring phenology to warming across temporal and spatial climate gradients in two independent databases
Benjamin I. Cook, Elizabeth M. Wolkovich, T. Jonathan Davies, Toby R. Ault, Julio L. Betancourt, Jenica M. Allen, Kjell Bolmgren, Elsa E. Cleland, Theresa Crimmins, Nathan J. B. Kraft, Lesley T. Lancaster, Susan J. Mazer, Gregory J. McCabe, Brian J. McGill, Camille Parmesan, Stephanie Pau, James Regetz, Nicolas Salamin, Mark D. Schwartz, Steven E. Travers
2012, Ecosystems (15) 1283-1294
Disparate ecological datasets are often organized into databases post hoc and then analyzed and interpreted in ways that may diverge from the purposes of the original data collections. Few studies, however, have attempted to quantify how biases inherent in these data (for example, species richness, replication, climate) affect their suitability...
Extended Kalman Filter framework for forecasting shoreline evolution
Joseph Long, Nathaniel G. Plant
2012, Geophysical Research Letters (39)
A shoreline change model incorporating both long- and short-term evolution is integrated into a data assimilation framework that uses sparse observations to generate an updated forecast of shoreline position and to estimate unobserved geophysical variables and model parameters. Application of the assimilation algorithm provides quantitative statistical estimates of combined model-data...
Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA
Carol A. Finn, Maria Deszcz-Pan, Paul A. Bedrosian
2012, Journal of Glaciology (58) 1133-1143
Ice-thickness measurements critical for flood and mudflow hazard studies are very sparse on Cascade Range (North America) volcanoes. Helicopter electromagnetic (HEM) data collected to detect hydrothermal alteration are used to determine ice thickness over portions of Mount Baker and Mount Adams volcanoes. A laterally continuous inversion method provides good estimates...
Impacts of climate change on ecosystem services
Peter Kareiva, Mary Ruckleshaus, Katie K. Arkema, Gary Geller, Evan Girvetz, Dave Goodrich, Erik Nelson, Virginia Matzek, Malin Pinsky, Walt Reid, Martin Saunders, Darius J. Semmens, Heather Tallis
2012, Book chapter, Impacts of climate change on biodiversity, ecosystems, and ecosystem services: technical input to the 2013 National Climate Assessment
Key Findings By 2050, climate change will triple the fraction of counties in the U.S. that are at high or extremely high risk of outstripping their water supplies (from 10 percent to 32 percent). The most at risk areas in the U.S. are the West, Southwest and Great Plains regions....
Corals are the building blocks of reefs
Steven L. Miller, Eugene A. Shinn, Barbara H. Lidz
William L. Kruczynski, Pamela J. Fletcher, editor(s)
2012, Book chapter, Tropical connections: South Florida's marine environment
No abstract available....
Forestry
Jason M. Stoker
2012, Book chapter, Manual of airborne topographic lidar
No abstract available....
Bedrock basins in the Sierra Nevada, Alta California
James G. Moore, Mary A. Gorden, Thomas W. Sisson
2012, California Archaeology (4) 99-122
A 360-km-long belt of more than 1,400 meter-sized granitic bedrock basins occurs at 1,200 to 2,500 m elevation on the west flank of the Sierra Nevada. The circular, smooth basins are 0.7 to 1.7 min diameter and are commonly 50 to 1,000 liters in volume. They are man-made as shown by their restricted...
A program for handling map projections of small-scale geospatial raster data
Michael P. Finn, Daniel R. Steinwand, Jason R. Trent, Robert A. Buehler, David M. Mattli, Kristina H. Yamamoto
2012, Cartographic Perspectives (71) 53-67
Scientists routinely accomplish small-scale geospatial modeling using raster datasets of global extent. Such use often requires the projection of global raster datasets onto a map or the reprojection from a given map projection associated with a dataset. The distortion characteristics of these projection transformations can have significant effects on modeling...
Status and trends of pelagic prey fishes in Lake Huron, 2012
David M. Warner, Timothy P. O’Brien, Steve A. Farha, Jeff Schaeffer, Stephen Lenart
2012, Report
The USGS Great Lakes Science Center (GLSC) conducted acoustic/midwater trawl surveys of Lake Huron during 1997 and annually during 2004-2012. The 2012 survey was conducted during September and October, and included transects in Lake Huron’s Main Basin, Georgian Bay, and North Channel. Pelagic fish density (638 fish/ha) was lower in...
Application of the control volume mixed finite element method to a triangular discretization
Richard L. Naff
2012, International Journal for Numerical Methods in Engineering (89) 846-868
A two‐dimensional control volume mixed finite element method is applied to the elliptic equation. Discretization of the computational domain is based in triangular elements. Shape functions and test functions are formulated on the basis of an equilateral reference triangle with unit edges. A pressure support based on...
Significant motions between GPS sites in the New Madrid region: implications for seismic hazard
Arthur Frankel, Robert Smalley, J. Paul
2012, Bulletin of the Seismological Society of America (102) 479-489
Position time series from Global Positioning System (GPS) stations in the New Madrid region were differenced to determine the relative motions between stations. Uncertainties in rates were estimated using a three‐component noise model consisting of white, flicker, and random walk noise, following the methodology of Langbein, 2004. Significant motions of...
Aftershocks halted by static stress shadows
Shinji Toda, Ross S. Stein, Gregory C. Beroza, David Marsan
2012, Nature Geoscience (5) 410-413
Earthquakes impart static and dynamic stress changes to the surrounding crust. Sudden fault slip causes small but permanent—static—stress changes, and passing seismic waves cause large, but brief and oscillatory—dynamic—stress changes. Because both static and dynamic stresses can trigger earthquakes within several rupture dimensions of a mainshock, it has proven difficult...
Analysis of host genetic diversity and viral entry as sources of between-host variation in viral load
Andrew R. Wargo, Alison M. Kell, Robert J. Scott, Gary H. Thorgaard, Gael Kurath
2012, Virus Research (165) 71-80
Little is known about the factors that drive the high levels of between-host variation in pathogen burden that are frequently observed in viral infections. Here, two factors thought to impact viral load variability, host genetic diversity and stochastic processes linked with viral entry into the host, were examined. This work...
Repeat surveys of spawning cisco (Coregonus artedi) in western Lake Superior: Timing, distribution and composition of spawning stocks
Daniel L. Yule, Donald R. Schreiner, Peter A. Addison, Michael J. Seider, Lori M. Evrard, Steven A. Geving, Henry R. Quinlan
2012, Advances in Limnology (63) 65-87
Acoustic (AC) and midwater trawl (MT) surveys of spawning cisco (Coregonus artedi) in Lake Superior have been combined with commercial yield to estimate exploitation. To time surveys properly, it is important to understand when adults typically arrive at spawning grounds and how numbers change as the spawning season progresses. We...
Population genetic structure of a widespread coniferous tree, Taxodium distichum [L.] Rich. (Cupressaceae), in the Mississippi River Alluvial Valley and Florida
Ayako Tanaka, Masato Ohtani, Yoshihisa Suyama, Nobuyuki Inomata, Yoshihiko Tsumura, Beth A. Middleton, Hidenori Tachida, Junko Kusumi
2012, Tree Genetics and Genomes (8) 1135-1147
Studies of genetic variation can elucidate the structure of present and past populations as well as the genetic basis of the phenotypic variability of species. Taxodium distichum is a coniferous tree dominant in lowland river flood plains and swamps of the southeastern USA which exhibits morphological variability and adaption to...
New Zealand’s deadliest quake sounds alarm for cities on fault lines
Erol Kalkan
2012, Natural Hazards Observer (36) 1-4
The catastrophic Christ Church Earthquake is a strong reminder to engineers and scientists of the hazards pose by fault lines, both mapped and unknown, near major cities. In February 2011, the relatively moderate earthquake that struck the cities of Christchurch and Lyttleton in the Canterbury region of New Zealand's South...
Distributional changes of American martens and fishers in eastern North America, 1699-2001: Chapter 4
William B. Krohn
2012, Book chapter, Biology and Conservation of Martens, Sables, and Fishers: A New Synthesis
Contractions in the geographic distributions of the American marten ( Martes americana) and fi sher ( M. pennanti) in eastern North America south of the St. Lawrence River between Colonial times (ca. 1650–1800) and the fi sher’s recent range expansion (ca. 1930–present) are well documented, but causal factors in these...
Sexual selection and mating chronology of Lesser Prairie-Chickens
Adam C. Behney, Blake A. Grisham, Clint W. Boal, Heather A. Whitlaw, David A. Haukos
2012, Wilson Journal of Ornithology (124) 96-105
Little is known about mate selection and lek dynamics of Lesser Prairie-Chickens (Tympanuchus pallidicinctus). We collected data on male territory size and location on leks, behavior, and morphological characteristics and assessed the importance of these variables on male Lesser Prairie-Chicken mating success during spring 2008 and 2009 in the Texas...
Mineralogy and environmental geochemistry of historical iron slag, Hopewell Furnace National Historic Site, Pennsylvania, USA
Nadine M. Piatak, Robert R. Seal
2012, Applied Geochemistry (27) 623-643
The Hopewell Furnace National Historic Site in southeastern Pennsylvania, which features an Fe smelter that was operational in the 18th and 19th centuries, is dominated by three slag piles. Pile 1 slag, from the Hopewell Furnace, and pile 2 slag, likely from the nearby Cornwall Furnace, were both produced...
Provisioning of nestling Dickcissels in native warm-season grass field buffers
K. L. Mitchell, Samuel K. Riffell, L. Wes Burger Jr., Francisco Vilella
2012, Wilson Journal of Ornithology (124) 298-309
We used video cameras in 2008–2009 to record provisioning activities at Dickcissel (Spiza americana) nests in and around Conservation Reserve Program field buffers in north-central Mississippi, USA. We simultaneously observed foraging flight distances of parents. Provisioning rate (P = 0.412), biomass (P = 0.161), and foraging distance (P = 0.159)...
Long-term impacts of invasive species on a native top predator in a large lake system
Scott A. Rush, Gordon Paterson, Tim B. Johnson, Ken G. Drouillard, Gordon D. Haffner, Craig E. Hebert, Michael T. Arts, Daryl J. McGoldrick, Sean M. Backus, Brian F. Lantry, Jana R. Lantry, Ted Schaner, Aaron T. Fisk
2012, Freshwater Biology (57) 2342-2355
1. Declining abundances of forage fish and the introduction and establishment of non-indigenous species have the potential to substantially alter resource and habitat exploitation by top predators in large lakes. 2. We measured stable isotopes of carbon (δ13C) and nitrogen (δ15N) in field-collected and archived samples of Lake Ontario lake trout (Salvelinus...
Using computational modeling of river flow with remotely sensed data to infer channel bathymetry
Jonathan M. Nelson, Richard R. McDonald, Paul J. Kinzel, Y. Shimizu
2012, Conference Paper, IAHR Riverflow 2012 Conference Proceedings
As part of an ongoing investigation into the use of computational river flow and morphodynamic models for the purpose of correcting and extending remotely sensed river datasets, a simple method for inferring channel bathymetry is developed and discussed. The method is based on an inversion of the equations expressing conservation...