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Page 1537, results 38401 - 38425

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Listening to Glaciers: Passive hydroacoustics near marine-terminating glaciers
E.C. Pettit, J.A. Nystuen, Shad O’Neel
2012, Oceanography (25) 104-105
The catastrophic breakup of the Larsen B Ice Shelf in the Weddell Sea in 2002 paints a vivid portrait of the effects of glacier-climate interactions. This event, along with other unexpected episodes of rapid mass loss from marine-terminating glaciers (i.e., tidewater glaciers, outlet glaciers, ice streams, ice shelves) sparked intensified...
Food availability and offspring sex in a monogamous seabird: insights from an experimental approach
Thomas Merkling, Sarah Leclaire, Etienne Danchin, Emeline Lhuillier, Richard H. Wagner, Joel White, Scott A. Hatch, Pierrick Blanchard
2012, Behavioral Ecology (23) 751-758
Sex allocation theory predicts that parents should favor offspring of the sex that provides the greatest fitness return. Despite growing evidence suggesting that vertebrates are able to overcome the constraint of chromosomal sex determination, the general pattern remains equivocal, indicating a need for experimental investigations. We used an experimental feeding...
Northern Rockies Ecoregion: Chapter 7 in Status and trends of land change in the Western United States--1973 to 2000
Janis L. Taylor
2012, Professional Paper 1794-A-7
The Northern Rockies Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 162,746 km2 (63,200 mi2), primarily in Idaho but also including areas in western Montana and northeastern Washington (fig. 1). Canada forms the northern border of the ecoregion. To the west it is bordered by the Columbia Plateau...
Montana Valley and Foothill Prairies Ecoregion: Chapter 6 in Status and trends of land change in the Western United States--1973 to 2000
Janis L. Taylor
2012, Professional Paper 1794-A-6
The Montana Valley and Foothill Prairies Ecoregion comprises numerous intermountain valleys and low-elevation foothill prairies spread across the western half of Montana, on both sides of the Continental Divide (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion, which covers approximately 64,658 km2 (24,965 mi2), includes the Flathead Valley and...
Vegetation shifts observed in arctic tundra 17 years after fire
Kirsten Barrett, Adrian V. Rocha, Martine Janet van de Weg, Gaius Shaver
2012, Remote Sensing Letters (3) 729-736
With anticipated climate change, tundra fires are expected to occur more frequently in the future, but data on the long-term effects of fire on tundra vegetation composition are scarce. This study addresses changes in vegetation structure that have persisted for 17 years after a tundra fire on the North Slope...
Canadian Rockies Ecoregion: Chapter 4 in Status and trends of land change in the Western United States--1973 to 2000
Janis L. Taylor
2012, Professional Paper 1794-A-4
The Canadian Rockies Ecoregion covers approximately 18,494 km2 (7,141 mi2) in northwestern Montana (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The east side of the ecoregion is bordered by the Montana Valley and Foothill Prairies Ecoregion, which also forms a large part of the western border of the ecoregion. In...
Southern Rockies Ecoregion: Chapter 8 in Status and trends of land change in the Western United States--1973 to 2000
Mark A. Drummond
2012, Professional Paper 1794-A-8
The Southern Rockies Ecoregion is a high-elevation mountainous ecoregion that covers approximately 138,854 km2 (53,612 mi2), including much of central Colorado and parts of southern Wyoming and northern New Mexico (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). It abuts six other ecoregions: the Wyoming Basin and Colorado Plateaus...
Middle Rockies Ecoregion: Chapter 5 in Status and trends of land change in the Western United States--1973 to 2000
Janis L. Taylor
2012, Professional Paper 1794-A-5
The Middle Rockies Ecoregion—characterized by steep, high-elevation mountain ranges and intermountain valleys—is a disjunct ecoregion composed of three distinct geographic areas: the Greater Yellowstone area in northwest Wyoming, southwest Montana, and eastern Idaho; the Bighorn Mountains in north-central Wyoming and south-central Montana; and the Black Hills in western South Dakota...
Interactions between methylmercury and selenomethionine injected into mallard eggs
J.D. Klimstra, J.L. Yee, G. H. Heinz, D. J. Hoffman, K.R. Stebbins
2012, Environmental Toxicology and Chemistry (31) 579-584
Methylmercury chloride and seleno-L-methionine were injected separately or in combinations into mallard eggs (Anas platyrhynchos), and embryo mortality and teratogenic effects (deformities) were modeled using a logistic regression model. Methylmercury was injected at doses that resulted in concentrations of 0, 0.2, 0.4, 0.8, and 1.6 µg/g Hg in the...
Assessing future risks to agricultural productivity, water resources and food security: How can remote sensing help?
Prasad S. Thenkabail, Jerry W. Knox, Mutlu Ozdogan, Murali Krishna Gumma, Russell G. Congalton, Zhuoting Wu, Cristina Milesi, Alex Finkral, Mike Marshall, Isabella Mariotto, Songcai You, Chandra Giri, Pamela Nagler
2012, Photogrammetric Engineering and Remote Sensing (78) 773-782
Although global food production has been rising, the world sti ll faces a major food security challenge. Over one billion people are currently undernourished (Wheeler and Kay, 2010). By the 2050s, the human population is projected to grow to 9.1 billion. Over three-quarters of these people will be living in...
Application of Wind Fetch and Wave Models for Habitat Rehabilitation and Enhancement Projects
Jason J. Rohweder, James T. Rogala, Barry L. Johnson, Dennis Anderson, Steve Clark, Ferris Chamberlin
2012, Conference Paper, Annual Meeting of the American Fisheries Society
Models based upon coastal engineering equations have been developed to quantify wind fetch length and several physical wave characteristics including significant height, length, peak period, maximum orbital velocity, and shear stress. These models were used to quantify differences in proposed island construction designs for three Habitat Rehabilitation and Enhancement Projects...
A Bayesian spawning habitat suitability model for American shad in southeastern United States rivers
Joseph E. Hightower, Julianne E. Harris, Joshua K. Raabe, Prescott Brownell, C. Ashton Drew
2012, Journal of Fish and Wildlife Management (3) 184-198
Habitat suitability index models for American shad Alosa sapidissima were developed by Stier and Crance in 1985. These models, which were based on a combination of published information and expert opinion, are often used to make decisions about hydropower dam operations and fish passage. The purpose of this study was to develop...
Using surface velocities to calculate ice thickness and bed topography: A case study at Columbia Glacier, Alaska, USA
R.W. McNabb, R. Hock, Shad O’Neel, Lowell A. Rasmussen, Y. Ahn, M. Braun, H. Conway, S. Herreid, I. Joughin, W.T. Pfeffer, B.E. Smith, M. Truffer
2012, Journal of Glaciology (58) 1151-1164
Information about glacier volume and ice thickness distribution is essential for many glaciological applications, but direct measurements of ice thickness can be difficult and costly. We present a new method that calculates ice thickness via an estimate of ice flux. We solve the familiar continuity equation between adjacent flowlines, which...
Spatial and temporal patterns of surface water quality and ichthyotoxicity in urban and rural river basins in Texas
Matthew M. VanLandeghem, Matthew D. Meyer, Stephen B. Cox, Bibek Sharma, Reynaldo Patino
2012, Water Research (20) 6638-6651
The Double Mountain Fork Brazos River (Texas, USA) consists of North (NF) and South Forks (SF). The NF receives urban runoff and twice-reclaimed wastewater effluent, whereas the SF flows through primarily rural areas. The objective of this study was to determine and compare associations between standard water quality variables and...
Arizona/New Mexico Plateau Ecoregion: Chapter 26 in Status and trends of land change in the Western United States--1973 to 2000
Jana Ruhlman, Leila Gass, Barry Middleton
2012, Professional Paper 1794-A-26
Situated between ecoregions of distinctly different topographies and climates, the Arizona/New Mexico Plateau Ecoregion represents a large area of approximately 192,869 km2 (74,467 mi2) that stretches across northern Arizona, central and northwestern New Mexico, and parts of southwestern Colorado; in addition, a small part extends into southeastern Nevada (fig. 1)...
Extreme weather and experience influence reproduction in an endangered bird
Brian E. Reichert, Christopher E. Cattau, Robert J. Fletcher Jr., William L. Kendall, Wiley M. Kitchens
2012, Ecology (93) 2580-2589
Extreme weather events, such as droughts and heat waves, are expected to become more severe and more frequent in the coming years, and understanding their impacts on demographic rates is of increasing interest to both evolutionary ecologists and conservation practitioners. An individual's breeding probability can be a sensitive indicator...
North Cascades Ecoregion: Chapter 14 in Status and trends of land change in the Western United States--1973 to 2000
Tamara S. Wilson
2012, Professional Paper 1794-A-14
The North Cascades Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 30,421 km2 (11,746 mi2) of predominantly steep, mountainous terrain, home to peaks rising more than 3,000 m, which are carved by valleys that drop below 150 m elevation (fig. 1). The unique topography in this geographically isolated...
Sonoran Basin and Range Ecoregion: Chapter 30 in Status and trends of land change in the Western United States--1973 to 2000
James P. Calzia, Tamara S. Wilson
2012, Professional Paper 1794-A-30
The Sonoran Basin and Range Ecoregion covers approximately 116,364 km2 (44,928 mi2) of desert landscape in southeastern California and southwestern Arizona (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). This ecoregion is bounded on the west by the Southern and Central California Chaparral and Oak Woodlands and the Southern...
Cascades Ecoregion: Chapter 11 in Status and trends of land change in the Western United States--1973 to 2000
Daniel G. Sorenson
2012, Professional Paper 1794-A-11
The Cascades Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 46,787 km2 (18,064 mi2) in Washington, Oregon, and California (fig. 1). The main body of the ecoregion extends from Snoqualmie Pass, Washington, in the north, to Hayden Mountain, near State Highway 66 in southern Oregon. Also included in...
Mojave Basin and Range Ecoregion: Chapter 29 in Status and trends of land change in the Western United States--1973 to 2000
Benjamin M. Sleeter, Christian G. Raumann
2012, Professional Paper 1794-A-29
This chapter has been modified from original material published in Sleeter and Raumann (2006), entitled “Land-cover trends in the Mojave Basin and Range Ecoregion” (U.S. Geological Survey Scientific Investigations Report 2006–5098). The Mojave Basin and Range Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 130,922 km2 (50,549 mi2)...
Arizona/New Mexico Mountains Ecoregion: Chapter 10 in Status and trends of land change in the Western United States--1973 to 2000
Jana Ruhlman, Leila Gass, Barry Middleton
2012, Professional Paper 1794-A-10
As the name suggests, the Arizona/New Mexico Mountains Ecoregion includes much of the mountainous regions of these two states, plus a very small part in the Guadalupe Mountains of northwestern Texas. Several isolated areas of higher terrain in Arizona and New Mexico are also included in the ecoregion, which occupies...
Wasatch and Uinta Mountains Ecoregion: Chapter 9 in Status and trends of land change in the Western United States--1973 to 2000
Mark S. Brooks
2012, Professional Paper 1794-A-9
The Wasatch and Uinta Mountains Ecoregion covers approximately 44,176 km2 (17, 057 mi2) (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). With the exception of a small part of the ecoregion extending into southern Wyoming and southern Idaho, the vast majority of the ecoregion is located along the eastern...
Northern Basin and Range Ecoregion: Chapter 23 in Status and trends of land change in the Western United States--1973 to 2000
Christopher E. Soulard
2012, Professional Paper 1794-A-23
The Northern Basin and Range Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) is located in eastern Oregon (58.7 percent), northern Nevada (20.6 percent), southwestern Idaho (14.8 percent), and northeastern California (5.9 percent), encompassing the northern extent of the hydrographic Great Basin (Grayson, 1993). The ecoregion, which covers approximately 110,039...
Columbia Plateau Ecoregion: Chapter 22 in Status and trends of land change in the Western United States--1973 to 2000
Benjamin M. Sleeter
2012, Professional Paper 1794-A-22
Located in eastern Washington and northern Oregon, the Columbia Plateau Ecoregion is characterized by sagebrush steppe and grasslands with extensive areas of dryland farming and irrigated agriculture. The ecoregion, which is approximately 90,059 km2 (34,772 mi2), is surrounded on all sides by mountainous ecoregions: to the west, the North Cascades...