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

183944 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 838, results 20926 - 20950

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Bioactive contaminants of emerging concern in National Park waters of the northern Colorado Plateau, USA
Rebecca H Weissinger, Brett R. Blackwell, Kristen Keteles, William A. Battaglin, Paul M. Bradley
2018, Science of the Total Environment (636) 910-918
Pharmaceuticals and personal care products (PPCPs), wastewater indicators (WWIs), and pesticides (herein, Contaminants of Emerging Concern [CECs]) have been documented in surface waters throughout the world and have associated risks to aquatic life. While much research has focused on temperate and urbanized watersheds, less is known about CEC presence in...
Late Quaternary loess and soils on uplands in the Canyonlands and Mesa Verde areas, Utah and Colorado
Marith C. Reheis, Harland L. Goldstein, Richard L. Reynolds, Steven L. Forman, Shannon A. Mahan, Paul E. Carrara
2018, Quaternary Research (89) 718-738
Thin loess deposits on the uplands of the southeastern Colorado Plateau have previously not been well studied. We sampled deposits and soils from trenches on Hatch Point (HP) mesa near Canyonlands National Park, Utah, and from two outcrops in Mesa Verde National Park, Colorado. At HP, the oldest buried unit...
Plant and microbial biomarkers suggest mechanisms of soil organic carbon accumulation in a Mojave Desert ecosystem under elevated CO2
Akihiro Koyama, Benjamin Harlow, Cheryl R. Kuske, Jayne Belnap, R. Dave Evans
2018, Soil Biology and Biochemistry (120) 48-57
We investigated how properties of soil organic matter (SOM) were altered after 10 years exposure to elevated atmospheric CO2 concentration ([CO2]) in a Mojave Desert ecosystem, using plant and microbial biomarkers. We focused on roles of Larrea tridentata, the dominant evergreen shrub which form islands of fertility, and biological soil crusts which have extensive cover in...
Spatial distribution of estuarine diamond-backed terrapins (Malaclemys terrapin) and risk analysis from commercial blue crab (Callinectes sapidus) trapping at the Savannah Coastal Refuges Complex, USA
Jeffrey E. Lovich, Meagan Thomas, Kirsten E. Ironside, Charles B. Yackulic, Shellie R. Puffer
2018, Ocean and Coastal Management (157) 160-167
The diamond-backed terrapin (Malaclemys terrapin) is a small estuarine turtle distributed along the Atlantic and Gulf Coasts of the USA. Terrapin populations are declining throughout their range and one of the main causes is mortality by drowning as bycatch in commercially-fished blue crab (Callinetes sapidus) traps (aka pots). We conducted...
Thermal tolerance limits of the Chinese mystery snail (Bellamya chinensis): Implications for management
Jessica L. Burnett, Kevin L. Pope, Alec Wong, Craig R. Allen, Danielle M. Haak, Bruce J. Stephen, Daniel R. Uden
2018, American Malacological Bulletin (36) 140-144
The Chinese mystery snail, Bellamya chinensis (Gray, 1834) is a gastropod native to East Asia and is considered an invasive species in North America where its impacts on native species and ecosystems are not well understood. Scientific literature describing its biology and life history are sparse. Thermal tolerance limits, or the maximum...
Cambarus loughmani, a new species of crayfish (Decapoda: Cambaridae) endemic to the pre-glacial Teays River Valley in West Virginia, USA
David A. Foltz II, Nichole Sadecky, Greg Myers, Fetzner, Stuart A. Welsh, Whitney Stockner, Mael Glon, Roger F. Thoma
2018, Journal of Natural History (52) 2875-2897
A new species of crayfish, Cambarus loughmani sp. nov., is described from the preglacial Teays River Valley of Cabell, Kanawha, Lincoln, Mason, and Putnam counties, West Virginia. The species was previously considered to be part of the Cambarus dubius complex. Loughman et al. restricted C. dubius to an orange colour morph found in central and northern...
Strong variation in weathering of layered rock maintains hillslope‐scale strength under high precipitation
Jennifer Von Voigtlander, Marin K. Clark, Dimitrios Zekkos, William W. Greenwood, Suzanne P. Anderson, Robert S. Anderson, Jonathan W. Godt
2018, Earth Surface Processes and Landforms (43) 1183-1194
The evolution of volcanic landscapes and their landslide potential are both dependent upon the weathering of layered volcanic rock sequences. We characterize critical zone structure using shallow seismic Vp and Vs profiles and vertical exposures of rock across a basaltic climosequence on Kohala peninsula, Hawai’i, and exploit the dramatic gradient in mean annual precipitation...
Integrating forest inventory data and MODIS data to map species-level biomass in Chinese boreal forests
Qinglong Zhang, Hong S. He, Yu Liang, Todd Hawbaker, Paul D. Henne, Jinxun Liu, Shengli Huang, Zhiwei Wu, Chao Huang
2018, Canadian Journal of Forest Research (48) 461-479
Timely and accurate knowledge of species-level biomass is essential for forest managers to sustain forest resources and respond to various forest disturbance regimes. In this study, maps of species-level biomass in Chinese boreal forests were generated by integrating Moderate Resolution Imaging Spectroradiometer (MODIS) images with forest inventory data using k nearest neighbor...
Demographic rates of two southeastern populations of Painted Bunting, 2007–2015
Liani M. Yirka, Jaime A. Collazo, Brian J. O’Shea, J.A. Gerwin, James A. Rotenberg, David T. Cobb
2018, The Condor (120) 319-329
Painted Buntings (Passerina ciris) have been declining in the southeastern United States since the 1970s. A recent demographic assessment highlighted the importance of estimating demographic parameters, which have received little attention to date. The dearth of information is troublesome because attempts to reverse declining trends require a better understanding of...
Process convolution approaches for modeling interacting trajectories
Henry R. Scharf, Mevin Hooten, Devin S. Johnson, John W. Durban
2018, Environmetrics (29)
Gaussian processes are a fundamental statistical tool used in a wide range of applications. In the spatiotemporal setting, several families of covariance functions exist to accommodate a wide variety of dependence structures arising in different applications. These parametric families can be restrictive and are insufficient in some situations. In contrast,...
Numerical model of geochronological tracers for deposition and reworking applied to the Mississippi subaqueous delta
Justin J. Birchler, Courtney K. Harris, Tara A. Kniskern, Christopher R. Sherwood
2018, Journal of Coastal Research (Special Issue 85) 456-460
Measurements of naturally occurring, short-lived radioisotopes from sediment cores on the Mississippi subaqueous delta have been used to infer event bed characteristics such as depositional thicknesses and accumulation rates. Specifically, the presence of Beryllium-7 (7Be) indicates recent riverine-derived terrestrial sediment deposition; while Thorium-234 (234Th) provides evidence of recent suspension in...
Groundwater-level data from an earthen dam site in southern Westchester County, New York
Michael L. Noll, Anthony Chu
2018, Data Series 1075
In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in Westchester County, New York. Groundwater levels were collected at 49 wells...
Operational nowcasting of electron flux levels in the outer zone of Earth's radiation belt
Tim Coleman, James P. McCollough, Shawn L. Young, E. Joshua Rigler
2018, Space Weather (16) 501-518
We describe a lightweight, accurate nowcasting model for electron flux levels measured by the Van Allen probes. Largely motivated by Rigler et al. (2004, https://doi.org/10.1029/2003SW000036), we turn to a time‐varying linear filter of previous flux levels and Kp. We train and test this model on data gathered from the 2.10 MeV channel...
Multi-year high-frequency hydrothermal monitoring of selected high-threat Cascade Range volcanoes
I.M. Crankshaw, Stacey A. Archfield, A. C. Newman, Deborah Bergfeld, Laura E. Clor, Peter J. Kelly, William C. Evans, Kurt R. Spicer, Steven E. Ingebritsen
2018, Journal of Volcanology and Geothermal Research (356) 24-35
From 2009 to 2015 the U.S. Geological Survey (USGS) systematically monitored hydrothermal behavior at selected Cascade Range volcanoes in order to define baseline hydrothermal and geochemical conditions. Gas and water data were collected regularly at 25 sites on 10 of the highest-risk volcanoes in the Cascade Range. These sites include...
Estimating fluvial discharges coincident with 21st century coastal storms modeled with CoSMoS
Li H. Erikson, Andrea C. O'Neill, Patrick L. Barnard
2018, Journal of Coastal Research (Special Issue No. 85) 791-795
On the open coast, flooding is largely driven by tides, storm surge, waves, and in areas near coastal inlets, the magnitude and co-occurrence of high fluvial discharges. Statistical methods are typically used to estimate the individual probability of coastal storm and fluvial discharge occurrences for use in sophisticated flood hazard...
Atmospheric and surface climate associated with 1986–2013 wildfires in North America
Steven W. Hostetler, Patrick J. Bartlein, Jay R. Alder
2018, Journal of Geophysical Research: Biogeosciences (123) 1588-1609
We analyze climate simulations conducted with the RegCM3 regional climate model on 50‐ and 15‐km model grids to diagnose the dependence of wildfire incidence and area burned variations on monthly climate long‐term means and anomalies over North America for the period 1986–2013. We created a new wildfire database by merging...
Interaction between hydraulic fracture and a preexisting fracture under triaxial stress conditions
Saied Mighani, David A. Lockner, Brian D. Kilgore, Farrokh Sheibani, Brian Evans
2018, Conference Paper, SPE Hydraulic Fracturing Technology Conference and Exhibition
Enhanced reservoir connectivity generally requires maximizing the intersection between hydraulic fracture (HF) and preexisting underground natural fractures (NF), while having the hydraulic fracture cross the natural fractures (and not arrest). We have studied the interaction between a hydraulic fracture and a polished saw-cut fault. The experiments include a hydraulic fracture...
Identifying and eliminating sources of recreational water quality degradation along an urban coast
Meredith B. Nevers, Muruleedhara Byappanahalli, Dawn Shively, Paul M. Buszka, P. Ryan Jackson, Mantha S. Phanikumar
2018, Journal of Environmental Quality (47) 1042-1050
Restoration of highly degraded urban coastal waters often requires large-scale, complex projects, but in the interim, smaller-scale efforts can provide immediate improvements to water quality conditions for visitor use. We examined short-term efforts to improve recreational water quality near the Grand Calumet River (GC) in the Laurentian Great Lakes. Identified...
The influence of sea level rise on the regional interdependence of coastal infrastructure
Ruo-Quian Wang, Mark T. Stacey, Liv M. Herdman, Patrick L. Barnard, Li H. Erikson
2018, Earth's Future (6) 677-688
Sea level rise (SLR) is placing both immediate and long‐term pressures on coastal communities to take protective actions. Projects in the United States, and in many locations throughout the world, generally involve local jurisdictions raising the elevation of shoreline protection elements, with limited or no analysis of the feedback between...
Effects of water-level management and hatchery supplementation on kokanee recruitment in Lake Pend Oreille, Idaho
Steven L. Whitlock, Michael Quist, Andrew M. Dux
2018, Article
Resource managers have been attempting to recover the kokanee (Oncorhynchus nerka) population in Lake Pend Oreille, Idaho for more than three decades using an annual stocking program and an experimental water-level management strategy. This study evaluated the effect of both management actions on kokanee recruitment. A bootstrap-based generalized Ricker model...
Warming is driving decreases in snow fractions while runoff efficiency remains mostly unchanged in snow-covered areas of the western United States
Gregory J. McCabe, David M. Wolock, Melissa Valentin
2018, Journal of Hydrometeorology (19) 803-814
Winter snowfall and accumulation is an important component of the surface water supply in the western United States. In these areas, increasing winter temperatures T associated with global warming can influence the amount of winter precipitation P that falls as snow S. In this study we examine long-term trends in the fraction of winter P that falls...
Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU
Kenneth Tiffan, John M. Plumb, Russell W. Perry, John Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn N. Rhodes, William P. Connor, Frank L. Mullins
2018, Report
The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2017 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat...
Wetlands receiving water treated with coagulants improve water quality by removing dissolved organic carbon and disinfection byproduct precursors
Angela M. Hansen, Tamara E. C. Kraus, Sandra M. Bachand, William R. Horwath, Philip Bachand
2018, Science of the Total Environment (622-623) 603-613
Constructed wetlands are used worldwide to improve water quality while also providing critical wetland habitat. However, wetlands have the potential to negatively impact drinking water quality by exporting dissolved organic carbon (DOC) that upon disinfection can form disinfection byproducts (DBPs) like trihalomethanes (THMs) and haloacetic acids (HAAs). We used a replicated field-scale study located on organic rich...
Genetic structure in Elk persists after translocation
Lisa I Muller, Jennifer L. Murrow, Jason L. Lupardus, Joseph D. Clark, Joseph G. Yarkovich, William H. Stiver, E. Kim Delozier, Brittany L. Slabach, John L. Cox, Bradley F. Miller
2018, Journal of Wildlife Management (82) 1124-1134
Elk (Cervus canadensis) translocation success is thought to be facilitated by high post‐release herd cohesion and limited movements; both should ensure genetic mixing following release. Such mixing is important to reduce potential effects of inbreeding or genetic drift, which can be especially important in small founding...
Population dynamics of the northern tamarisk beetle (Diorhabda carinulata) in the Colorado River Basin
Levi R. Jamison, Charles van Riper III
2018, Open-File Report 2018-1070
Throughout the Southwestern United States, riparian systems contain narrow belts of vegetation along streams and rivers. Although only a small percentage of the total land cover, this ecosystem is important for maintaining high species diversity and population densities of birds. Anthropogenic changes to Western riverine systems have enhanced their susceptibility...