Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

165626 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 1276, results 31876 - 31900

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
The effects of changing land cover on streamflow simulation in Puerto Rico
Ashley E. Van Beusekom, Lauren E. Hay, Roland J. Viger, William A. Gould, Jaime Collazo, Azad Henareh Khalyani
2014, Journal of the American Water Resources Association (50) 1575-1593
This study quantitatively explores whether land cover changes have a substantive impact on simulated streamflow within the tropical island setting of Puerto Rico. The Precipitation Runoff Modeling System (PRMS) was used to compare streamflow simulations based on five static parameterizations of land cover with those based on dynamically varying parameters...
Paleogeomorphology of the early Colorado River inferred from relationships in Mohave and Cottonwood Valleys, Arizona, California and Nevada
Philip Pearthree, Kyle House
2014, Geosphere (10) 1139-1160
Geologic investigations of late Miocene–early Pliocene deposits in Mohave and Cottonwood valleys provide important insights into the early evolution of the lower Colorado River system. In the latest Miocene these valleys were separate depocenters; the floor of Cottonwood Valley was ∼200 m higher than the floor of Mohave Valley. When...
Pollutant sensitivity of the endangered Tar River Spinymussel as assessed by single chemical and effluent toxicity tests
Thomas P. Augspurger, Ning Wang, James L. Kunz, Christopher G. Ingersoll
2014, Report
The federally endangered Tar River spinymussel (Elliptio steinstansana) is endemic to the Tar River and Neuse River systems in North Carolina. The extent to which water quality limits Tar River spinymussels’ recovery is important to establish, and one aspect of that is understanding the species’ pollutant sensitivity. The primary objectives...
Freshwater mussels of Florida
James D. Williams, Robert S. Butler, Gary L. Warren, Nathan A. Johnson
2014, Book
An exhaustive guide to all aspects of the freshwater mussel fauna in Florida,Freshwater Mussels of Florida covers the ecology, biology, distribution, and conservation of the many species of bivalve mollusks in the Sunshine State. In the past three decades, researchers, the public, businesses that depend on wildlife, and policy makers have...
Genetic structure of Florida green turtle rookeries as indicated by mitochondrial DNA control region sequences
Brian M. Shamblin, Dean A. Bagley, Llewellyn M. Ehrhart, Nicole A. Desjardin, R. Erik Martin, Kristen M. Hart, Eugenia Naro-Maciel, Kirt Rusenko, John C. Stiner, Debra Sobel, Chris Johnson, Thomas Wilmers, Laura J. Wright, Campbell J. Nairn
2014, Conservation Genetics (16) 673-685
Green turtle (Chelonia mydas) nesting has increased dramatically in Florida over the past two decades, ranking the Florida nesting aggregation among the largest in the Greater Caribbean region. Individual beaches that comprise several hundred kilometers of Florida’s east coast and Keys support tens to thousands of nests annually. These beaches...
Inhalable desert dust, urban emissions, and potentially biotoxic metals in urban Saharan-Sahelian air
Virginia H. Garrison, Michael S. Majewski, Lassana Konde, Ruth E. Wolf, Richard D. Otto, Yutaka Tsuneoka
2014, Science of the Total Environment 383-394
Saharan dust incursions and particulates emitted from human activities degrade air quality throughout West Africa, especially in the rapidly expanding urban centers in the region. Particulate matter (PM) that can be inhaled is strongly associated with increased incidence of and mortality from cardiovascular and respiratory diseases and cancer. Air samples...
Waterfowl habitat use and selection during the remigial moult period in the northern hemisphere
Anthony D. Fox, Paul L. Flint, William L. Hohman, Jean-Pierre L. Savard
2014, Wildfowl 131-168
This paper reviews factors affecting site selection amongst waterfowl (Anatidae) during the flightless remigial moult, emphasising the roles of predation and food supply (especially protein and energy). The current literature suggests survival during flightless moult is at least as high as at other times of the annual cycle, but documented cases of predation of...
Physical properties of the WAIS Divide ice core
Joan J. Fitzpatrick, Donald E. Voigt, John M. Fegyveresi, Nathan T. Stevens, Matthew K. Spencer, Jihong Cole-Dai, Richard B. Alley, Gabriella E. Jardine, Eric Cravens, Lawrence A. Wilen, T. J. Fudge, Joseph R. McConnell
2014, Journal of Glaciology (60) 1181-1198
The WAIS (West Antarctic Ice Sheet) Divide deep ice core was recently completed to a total depth of 3405 m, ending ∼50 m above the bed. Investigation of the visual stratigraphy and grain characteristics indicates that the ice column at the drilling location is undisturbed by any large-scale overturning or...
Carryover effects and climatic conditions influence the postfledging survival of greater sage-grouse
Erik J. Blomberg, James S. Sedinger, Daniel Gibson, Peter S. Coates, Michael L. Casazza
2014, Ecology and Evolution (4) 4488-4499
Prebreeding survival is an important life history component that affects both parental fitness and population persistence. In birds, prebreeding can be separated into pre- and postfledging periods; carryover effects from the prefledging period may influence postfledging survival. We investigated effects of body condition at fledging, and climatic variation, on postfledging...
Estimating the volcanic emission rate and atmospheric lifetime of SO2 from space: a case study for Kīlauea volcano, Hawai'i
Steffen Beirle, Christoph Hormann, Malouse Penning de Vries, Stefan Dorner, Christoph Kern, Thomas Wagner
2014, Atmospheric Chemistry and Physics (14) 8309-8322
We present an analysis of SO2 column densities derived from GOME-2 satellite measurements for the Kīlauea volcano (Hawai`i) for 2007–2012. During a period of enhanced degassing activity in March–November 2008, monthly mean SO2 emission rates and effective SO2 lifetimes are determined simultaneously from the observed downwind plume evolution and meteorological wind fields, without...
Approximations of stand water use versus evapotranspiration from three mangrove forests in southwest Florida, USA
Ken W. Krauss, Jordan G. Barr, Victor C. Engel, Jose D. Fuentes, Hongqing Wang
2014, Agricultural and Forest Meteorology (213) 291-303
Leaves from mangrove forests are often considered efficient in the use of water during photosynthesis, but less is known about whole-tree and stand-level water use strategies. Are mangrove forests as conservative in water use as experimental studies on seedlings imply? Here, we apply a simple model to estimate stand water...
Drivers of waterfowl population dynamics: from teal to swans
David N. Koons, Gunnar Gunnarsson, Joel A. Schmutz, Jay J. Rotella
2014, Wildfowl 169-191
Waterfowl are among the best studied and most extensively monitored species in the world. Given their global importance for sport and subsistence hunting, viewing and ecosystem functioning, great effort has been devoted since the middle part of the 20th century to understanding both the environmental and demographic mechanisms that influence waterfowl population and community dynamics. Here we use comparative approaches to summarise and contrast our...
Characterizing riverbed sediment using high-frequency acoustics 1: spectral properties of scattering
Daniel D. Buscombe, Paul E. Grams, Matthew A. Kaplinski
2014, Journal of Geophysical Research F: Earth Surface (119) 2674-2691
Bed-sediment classification using high-frequency hydro-acoustic instruments is challenging when sediments are spatially heterogeneous, which is often the case in rivers. The use of acoustic backscatter to classify sediments is an attractive alternative to analysis of topography because it is potentially sensitive to grain-scale roughness. Here, a new method is presented...
Iron oxide minerals in dust of the Red Dawn event in eastern Australia, September 2009
Richard L. Reynolds, Stephen R. Cattle, Bruce M. Moskowitz, Harland L. Goldstein, Kimberly Yauk, Cody B. Flagg, Thelma S. Berquo, Raymond F. Kokaly, Suzette A. Morman, George N. Breit
2014, Aeolian Research (15) 1-13
Iron oxide minerals typically compose only a few weight percent of bulk atmospheric dust but are important for potential roles in forcing climate, affecting cloud properties, influencing rates of snow and ice melt, and fertilizing marine phytoplankton. Dust samples collected from locations across eastern Australia (Lake Cowal, Orange, Hornsby, and...
Eruptions at Lone Star geyser, Yellowstone National Park, USA: 2. Constraints on subsurface dynamics
Jean Vandemeulebrouck, Robert A. Sohn, Maxwell L. Rudolph, Shaul Hurwitz, Michael Manga, Malcolm J.S. Johnston, S. Adam Soule, Darcy McPhee, Jonathan M. G. Glen, Leif Karlstrom, Fred Murphy
2014, Journal of Geophysical Research B: Solid Earth (119) 8688-8707
We use seismic, tilt, lidar, thermal, and gravity data from 32 consecutive eruption cycles of Lone Star geyser in Yellowstone National Park to identify key subsurface processes throughout the geyser's eruption cycle. Previously, we described measurements and analyses associated with the geyser's erupting jet dynamics. Here we show that seismicity...
Relationships between land cover and dissolved organic matter change along the river to lake transition
James H. Larson, Paul C. Frost, Marguerite A. Xenopoulos, Clayton J. Williams, Ana M. Morales-Williams, Jonathan M. Vallazza, J. C. Nelson, William B. Richardson
2014, Ecosystems (17) 1413-1425
Dissolved organic matter (DOM) influences the physical, chemical, and biological properties of aquatic ecosystems. We hypothesized that controls over spatial variation in DOM quantity and composition (measured with DOM optical properties) differ based on the source of DOM to aquatic ecosystems. DOM quantity and composition should be better predicted by...
Identifying monitoring gaps for amphibian populations in a North American biodiversity hotspot, the southeastern USA
Susan C. Walls
2014, Biodiversity and Conservation (23) 3341-3357
I review the primary literature to ascertain the status of amphibian monitoring efforts in the southeastern USA, a “hotspot” for biodiversity in North America. This effort revealed taxonomic, geographic and ecological disparities in studies of amphibian populations in this region. Of the species of anurans and caudates known to occur...
Anuran site occupancy and species richness as tools for evaluating restoration of a hydrologically-modified landscape
Susan C. Walls, J. Hardin Waddle, William J. Barichivich, Ian A. Bartoszek, Mary E. Brown, J. M. Hefner, Melinda J. Schuman
2014, Wetlands Ecology and Management (22) 625-639
A fundamental goal of wetland restoration is to reinstate pre-disturbance hydrological conditions to degraded landscapes, facilitating recolonization by native species and the production of resilient, functional ecosystems. To evaluate restoration success, baseline conditions need to be determined and a reference target needs to be established that will serve as an...
Characterizing riverbed sediment using high-frequency acoustics 2: scattering signatures of Colorado River bed sediment in Marble and Grand Canyons
Daniel D. Buscombe, Paul E. Grams, Matthew A. Kaplinski
2014, Journal of Geophysical Research F: Earth Surface (119) 2692-2710
In this, the second of a pair of papers on the statistical signatures of riverbed sediment in high-frequency acoustic backscatter, spatially explicit maps of the stochastic geometries (length- and amplitude-scales) of backscatter are related to patches of riverbed surfaces composed of known sediment types, as determined by geo-referenced underwater video...
Late Holocene slip rate and ages of prehistoric earthquakes along the Maacama Fault near Willits, Mendocino County, northern California
Carol S. Prentice, Martin C. Larsen, Harvey M. Kelsey, Judith Zachariasen
2014, Bulletin of the Seismological Society of America (104) 2966-2984
The Maacama fault is the northward continuation of the Hayward–Rodgers Creek fault system and creeps at a rate of 5.7±0.1 mm/yr (averaged over the last 20 years) in Willits, California. Our paleoseismic studies at Haehl Creek suggest that the Maacama fault has produced infrequent large earthquakes in addition to creep. Fault...
What do we gain from simplicity versus complexity in species distribution models?
Cory Merow, Matthew J. Smith, Thomas C. Edwards Jr., Antoine Guisan, Sean M. McMahon, Signe Normand, Wilfried Thuiller, Rafael O. Wuest, Niklaus E. Zimmermann, Jane Elith
2014, Ecography (37) 1267-1281
Species distribution models (SDMs) are widely used to explain and predict species ranges and environmental niches. They are most commonly constructed by inferring species' occurrence–environment relationships using statistical and machine-learning methods. The variety of methods that can be used to construct SDMs (e.g. generalized linear/additive models, tree-based models, maximum entropy,...
Temporal and spatial changes in golden eagle reproduction in relation to increased off highway vehicle activity
Karen Steenhof, Jessi L. Brown, Michael N. Kochert
2014, Wildlife Society Bulletin (38) 682-688
We used >40 years of data on golden eagles (Aquila chrysaetos) nesting in southwestern Idaho, USA, to assess whether the proportion of territories and pairs producing young has changed over time, and whether territories in areas where off highway vehicle (OHV) use has increased significantly were less likely to be...
Effects of a dual-pump crude-oil recovery system, Bemidji, Minnesota, USA
Geoffrey N. Delin, William N. Herkelrath
2014, Groundwater Monitoring & Remediation (34) 57-67
A crude-oil spill occurred in 1979 when a pipeline burst near Bemidji, MN. In 1998, the pipeline company installed a dual-pump recovery system designed to remove crude oil remaining in the subsurface at the site. The remediation from 1999 to 2003 resulted in removal of about 115,000 L of crude...
Predicting occupancy for pygmy rabbits in Wyoming: an independent evaluation of two species distribution models
Steve Germaine, Drew Ignizio, Doug Keinath, Holly Copeland
2014, Journal of Fish and Wildlife Management (5) 298-314
Species distribution models are an important component of natural-resource conservation planning efforts. Independent, external evaluation of their accuracy is important before they are used in management contexts. We evaluated the classification accuracy of two species distribution models designed to predict the distribution of pygmy rabbit Brachylagus idahoensis habitat in southwestern Wyoming, USA....
Potential reduction in terrestrial salamander ranges associated with Marcellus shale development
Adrianne B. Brand, Amber N. M. Wiewel, Evan H. Campbell Grant
2014, Biological Conservation (180) 233-240
Natural gas production from the Marcellus shale is rapidly increasing in the northeastern United States. Most of the endemic terrestrial salamander species in the region are classified as ‘globally secure’ by the IUCN, primarily because much of their ranges include state- and federally protected lands, which have been presumed to...