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Not all publications have extents, not all extents are completely accurate
The fate and transport of nitrate in shallow groundwater in northwestern Mississippi, USA
Heather L. Welch, Christopher T. Green, Richard H. Coupe
2011, Hydrogeology Journal (19) 1239-1252
Agricultural contamination of groundwater in northwestern Mississippi, USA, has not been studied extensively, and subsurface fluxes of agricultural chemicals have been presumed minimal. To determine the factors controlling transport of nitrate-N into the Mississippi River Valley alluvial aquifer, a study was conducted from 2006 to 2008 to estimate fluxes of...
The evaluation of a rake method to quantify submersed vegetation in the Upper Mississippi River
Yao Yin, Rebecca M. Kreiling
2011, Hydrobiologia (675) 187-195
A long-handled, double-headed garden rake was used to collect submersed aquatic vegetation (SAV) and compared to in-boat visual inspection to record species presence at 67 individual sites. Six rake subsamples were taken at each site and a rake density rating was given to each species collected in the subsamples. Presence...
A multi-year comparison of IPCI scores for prairie pothole wetlands: implications of temporal and spatial variation
Ned H. Euliss Jr., David M. Mushet
2011, Wetlands (31) 713-723
In the prairie pothole region of North America, development of Indices of Biotic Integrity (IBIs) to detect anthropogenic impacts on wetlands has been hampered by naturally dynamic inter-annual climate fluctuations. Of multiple efforts to develop IBIs for prairie pothole wetlands, only one, the Index of Plant Community Integrity (IPCI), has...
US Topo - A new national map series
Laurence R. Moore
2011, Directions Magazine (2011)
In the second half of the 20th century, the foundation of the U.S. Geological Survey's national map series was the handcrafted 7.5-minute topographic map. Times change, budgets get squeezed and currency expectations become ever more challenging. The USGS's Larry Moore, who oversees data production operations at two National Geospatial Technical...
Predicting breeding habitat for amphibians: a spatiotemporal analysis across Yellowstone National Park
Paul E. Bartelt, Alisa L. Gallant, Robert W. Klaver, Christopher K. Wright, Debra A. Patla, Charles R. Peterson
2011, Ecological Applications (21) 2530-2547
The ability to predict amphibian breeding across landscapes is important for informing land management decisions and helping biologists better understand and remediate factors contributing to declines in amphibian populations. We built geospatial models of likely breeding habitats for each of four amphibian species that breed in Yellowstone National Park (YNP)....
Estimating riparian understory vegetation cover with beta regression and copula models
Bianca Eskelson, Lisa Madsen, Joan C. Hagar, Hailemariam Temesgen
2011, Forest Science (57) 212-221
Understory vegetation communities are critical components of forest ecosystems. As a result, the importance of modeling understory vegetation characteristics in forested landscapes has become more apparent. Abundance measures such as shrub cover are bounded between 0 and 1, exhibit heteroscedastic error variance, and are often subject to spatial dependence. These...
Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics
Kevin L. Monteith, Vernon C. Bleich, Thomas R. Stephenson, Beck M. Pierce, Mary M. Conner, Robert W. Klaver, R. Terry Bowyer
2011, Ecosphere (2)
Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in...
U.S. Geological Survey development of a Landsat-based Fire Disturbance ECV
Susan Stitt, John D. Guthrie, Todd Hawbaker, Mary S. Dolhancey
2011, Conference Paper, 34th International Symposium on Remote Sensing of Environment: The GEOSS Era: Towards Operational Environmental Monitoring: April 10-15, 2011, Sydney, Australia: Proceedings
The United States Geological Survey (USGS) is the steward of the Landsat archive which includes satellite imagery dating back to 1972. The United Nations Framework Convention on Climate Change and the Intergovernmental Panel on Climate Change have specified requirements to systematically observe atmosphere, ocean, and land characteristics, or Essential Climate...
SICS: the Southern Inland and Coastal System interdisciplinary project of the USGS South Florida Ecosystem Program
Water Resources Division, U.S. Geological Survey
2011, Report
State and Federal agencies are working jointly on structural modifications and improved water-delivery strategies to reestablish more natural surface-water flows through the Everglades wetlands and into Florida Bay. Changes in the magnitude, duration, timing, and distribution of inflows from the headwaters of the Taylor Slough and canal C-111 drainage basins...
Characterization of the intragranular water regime within subsurface sediments: pore volume, surface area, and mass transfer limitations
Michael B. Hay, Deborah L. Stoliker, James A. Davis, John M. Zachara
2011, Water Resources Research (47)
Although "intragranular" pore space within grain aggregates, grain fractures, and mineral surface coatings may contain a relatively small fraction of the total porosity within a porous medium, it often contains a significant fraction of the reactive surface area, and can thus strongly affect the transport of sorbing solutes. In this...
Geomagnetic referencing in the arctic environment
Benny Podjono, Nathan Beck, Andrew Buchanan, Jason Brink, Joseph Longo, Carol A. Finn, E. William Worthington
2011, Conference Paper
Geomagnetic referencing is becoming an increasingly attractive alternative to north-seeking gyroscopic surveys to achieve the precise wellbore positioning essential for success in today's complex drilling programs. However, the greater magnitude of variations in the geomagnetic environment at higher latitudes makes the application of geomagnetic referencing in those areas more challenging....
Rapid growth in the early marine period improves the marine survival of Chinook salmon (Oncorhynchus tshawytscha) in Puget Sound, Washington
Elisabeth J. Duffy, David A. Beauchamp
2011, Canadian Journal of Fisheries and Aquatic Sciences (68) 232-240
We examined the effect of early marine entry timing and body size on the marine (smolt-to-adult) survival of Puget Sound Chinook salmon (Oncorhynchus tshawytscha). We used data from coded wire tag release groups of hatchery Chinook salmon to test whether hatchery release date, release size, and size in offshore waters...
Land use and habitat conditions across the southwestern Wyoming sagebrush steppe: development impacts, management effectiveness and the distribution of invasive plants
Daniel J. Manier, Cameron L. Aldridge, Patrick Anderson, Geneva Chong, Collin G. Homer, Michael S. O’Donnell, Spencer Schell
2011, Natural Resources and Environmental Issues (117)
For the past several years, USGS has taken a multi-faceted approach to investigating the condition and trends in sagebrush steppe ecosystems. This recent effort builds upon decades of work in semi-arid ecosystems providing a specific, applied focus on the cumulative impacts of expanding human activities across these landscapes. Here, we...
The use of historical imagery in the remediation of an urban hazardous waste site
E. Terrence Slonecker
2011, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing (4) 281-291
The information derived from the interpretation of historical aerial photographs is perhaps the most basic multitemporal application of remote-sensing data. Aerial photographs dating back to the early 20th century can be extremely valuable sources of historical landscape activity. In this application, imagery from 1918 to 1927 provided a wealth of...
Use of cranial characters in taxonomy of the Minnesota wolf (Canis sp.)
L. David Mech, Ronald M. Nowak, Sanford Weisberg
2011, Canadian Journal of Zoology (89) 1188-1194
Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from...
Population demographics of catostomids in large river ecosystems: effects of discharge and temperature on recruitment dynamics and growth
M.C. Quist, J.R. Spiegel
2011, River Research and Applications (28) 1567-1586
Catostomids are among the most widespread and ecologically important groups of fishes in North America, particularly in large river systems. Despite their importance, little information is available on their population demographics and even less is known about factors influencing their population dynamics. The objectives of this study were to describe...
Hyperspectral analysis of rocky surfaces on the Earth and other planetary systems: Chapter 27
R. Greg Vaughan, Timothy N. Titus, Jeffery R Johnson, Justin Hagerty, Lisa R. Gaddis, Laurence A. Soderblom, Paul E. Geissler
Prasad S. Thenkabail, John G. Lyon, Alfredo Huete, editor(s)
2011, Book chapter, Hyperspectral remote sensing of vegetation
This book is focused on studies of vegetation on Earth using hyperspectral remote sensing methods. However, it is appropriate to extend the application of these methods out to other rocky bodies in our Solar System for a variety of reasons. First, minerals, soils, and rocks form the substrate on which...
Aquatic ecology of the Elwha River estuary prior to dam removal: Chapter 7 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal
Jeffrey J. Duda, Matthew M. Beirne, Kimberly Larsen, Dwight Barry, Karl Stenberg, Michael L. McHenry
Jeffrey J. Duda, Jonathan A. Warrick, Christopher S. Magirl, editor(s)
2011, Scientific Investigations Report 2011-5120-7
The removal of two long-standing dams on the Elwha River in Washington State will initiate a suite of biological and physical changes to the estuary at the river mouth. Estuaries represent a transition between freshwater and saltwater, have unique assemblages of plants and animals, and are a critical habitat for...
A trans-dimensional Bayesian Markov chain Monte Carlo algorithm for model assessment using frequency-domain electromagnetic data
Burke J. Minsley
2011, Geophysical Journal International (187) 252-272
A meaningful interpretation of geophysical measurements requires an assessment of the space of models that are consistent with the data, rather than just a single, ‘best’ model which does not convey information about parameter uncertainty. For this purpose, a trans-dimensional Bayesian Markov chain Monte Carlo (MCMC) algorithm is developed for...
Influence of dreissenid mussels on catchability of benthic fishes in bottom trawls
Patrick M. Kocovsky, Martin A. Stapanian
2011, Transactions of the American Fisheries Society (140) 1565-1573
Inferring trends in true abundance of fish populations from catch per unit effort data requires either the knowledge of capture probability or the assumption that it is constant, both of which are unlikely contingencies. We developed and validated an index of catchability (a proxy measure for capture probability) from a...
The influence of current speed and vegetation density on flow structure in two macrotidal eelgrass canopies
Jessica R. Lacy, Sandy Wyllie-Echeverria
2011, Limnology and Oceanography: Fluids and Environments (1) 38-55
The influence of eelgrass (Zostera marina) on near-bed currents, turbulence, and drag was investigated at three sites in two eelgrass canopies of differing density and at one unvegetated site in the San Juan archipelago of Puget Sound, Washington, USA. Eelgrass blade length exceeded 1 m. Velocity profiles up to 1.5...
Baseline hydrologic studies in the lower Elwha River prior to dam removal
Christopher S. Magirl, Christopher A. Curran, Rich W. Sheibley, Jonathan A. Warrick, Jonathan A. Czuba, Christiana R. Czuba, Andrew S. Gendaszek, Patrick B. Shafroth, Jeffrey J. Duda, James R. Foreman
2011, Scientific Investigations Report 2011-5120-4
After the removal of two large, long‑standing dams on the Elwha River, Washington, the additional load of sediment and wood is expected to affect the hydrology of the lower river, its estuary, and the alluvial aquifer underlying the surrounding flood plain. To better understand the surface-water and groundwater characteristics of...
Seismic hazard maps for Haiti
Arthur Frankel, Stephen Harmsen, Charles Mueller, Eric Calais, Jennifer Haase
2011, Earthquake Spectra (27) S23-S41
We have produced probabilistic seismic hazard maps of Haiti for peak ground acceleration and response spectral accelerations that include the hazard from the major crustal faults, subduction zones, and background earthquakes. The hazard from the Enriquillo-Plantain Garden, Septentrional, and Matheux-Neiba fault zones was estimated using fault slip rates determined from...